Sample records for rg zn cd

  1. Photoluminescence study of the substitution of Cd by Zn during the growth by atomic layer epitaxy of alternate CdSe and ZnSe monolayers

    SciTech Connect (OSTI)

    Hernández-Calderón, I. [Physics Department,Cinvestav, Ave. IPN2508, 07360, México City, DF. (Mexico); Salcedo-Reyes, J. C. [Thin Films Group, Physics Department, Pontificia Universidad Javeriana, Cr. 7 No. 43-82, Ed. 53, Lab. 404, Bogotá, D.C. (Colombia)

    2014-05-15T23:59:59.000Z

    We present a study of the substitution of Cd atoms by Zn atoms during the growth of alternate ZnSe and CdSe compound monolayers (ML) by atomic layer epitaxy (ALE) as a function of substrate temperature. Samples contained two quantum wells (QWs), each one made of alternate CdSe and ZnSe monolayers with total thickness of 12 ML but different growth parameters. The QWs were studied by low temperature photoluminescence (PL) spectroscopy. We show that the Cd content of underlying CdSe layers is affected by the exposure of the quantum well film to the Zn flux during the growth of ZnSe monolayers. The amount of Cd of the quantum well film decreases with higher exposures to the Zn flux. A brief discussion about the difficulties to grow the Zn{sub 0.5}Cd{sub 0.5}Se ordered alloy (CuAu-I type) by ALE is presented.

  2. Development of a new electrodeposition process for plating of Zn-Ni-X (X=Cd, P) alloys. 1. Corrosion characteristics of Zn-Ni-Cd ternary alloys

    SciTech Connect (OSTI)

    Durairajan, A.; Haran, B.S.; White, R.E.; Popov, B.N.

    2000-05-01T23:59:59.000Z

    A new Zn-Ni-Cd plating process was developed which offers a unique way of controlling and optimizing the Ni and Cd contents in the final deposit. Zinc-nickel-cadmium alloy was deposited from a 0.5 M NiSO{sub 4} + 0.2 M ZnSO{sub 4} bath in the presence of 0.015 M CdSO{sub 4} and 1 g/L nonyl phenyl polyethylene oxide. Using this process a Zn-Ni-Cd ternary alloy, with a higher nickel content as compared to that obtained from conventional Zn-Ni baths, was synthesized. The Zn-Ni-Cd alloy coatings deposited from an electrolyte containing 0.015 M (0.3%) CdSO{sub 4} has a Zn to Ni ratio of 2.5:1. The increase in nickel content accounts for the observed decrease in the corrosion potential to a value lower than that of Cd but higher than the corrosion potential of iron. The coatings have superior corrosion resistance and barrier properties than the typical Zn-Ni and cadmium coatings. Polarization studies and electrochemical impedance spectroscopy analysis on Zn-Ni-Cd coatings show a barrier resistance that is ten times higher than that of a conventional Zn-Ni coating.

  3. Temperature-dependent photoluminescence of CdZnO thin films grown by molecular-beam epitaxy

    E-Print Network [OSTI]

    Yang, Zheng

    performed on three typical CdZnO samples having pure wurtzite, pure rocksalt, and wurtzite­rocksalt mixture and analyzed based on the variable-temperature PL studies of typical wurtzite (wz) CdZnO, rocksalt (rs) Cd

  4. Coplanar grid CdZnTe detectors for space science applications Benjamin W. Sturm*a

    E-Print Network [OSTI]

    He, Zhong

    Coplanar grid CdZnTe detectors for space science applications Benjamin W. Sturm*a , Zhong Hea of the latest coplanar grid CdZnTe detectors, which use the third- generation coplanar grid design into the material properties as well as the charge induction uniformity of the detector. Keywords: coplanar grid, Cd

  5. Core-shell ITO/ZnO/CdS/CdTe nanowire solar cells

    SciTech Connect (OSTI)

    Williams, B. L.; Phillips, L.; Major, J. D.; Durose, K. [Stephenson Institute for Renewable Energy, University of Liverpool, Chadwick Building, Peach St., Liverpool L69 7ZF (United Kingdom); Taylor, A. A.; Mendis, B. G.; Bowen, L. [G. J. Russell Microscopy Facility, University of Durham, South Road, Durham DH1 3LE (United Kingdom)

    2014-02-03T23:59:59.000Z

    Radial p-n junction nanowire (NW) solar cells with high densities of CdTe NWs coated with indium tin oxide (ITO)/ZnO/CdS triple shells were grown with excellent heterointerfaces. The optical reflectance of the devices was lower than for equivalent planar films by a factor of 100. The best efficiency for the NW solar cells was ??=?2.49%, with current transport being dominated by recombination, and the conversion efficiencies being limited by a back contact barrier (?{sub B}?=?0.52?eV) and low shunt resistances (R{sub SH}?

  6. Rapid degradation of CdSe/ZnS colloidal quantum dots exposed to gamma irradiation

    E-Print Network [OSTI]

    New Mexico, University of

    Rapid degradation of CdSe/ZnS colloidal quantum dots exposed to gamma irradiation Nathan J. Withers are reported. Optical degradation is evaluated by tracking the dependence of photoluminescence intensity on irradiation dose. CdSe/ZnS quantum dots show poor radiation hardness, and severely degrade after less than 20

  7. A Novel Electrodeposition Process for Plating Zn-Ni-Cd Alloys Hansung Kim,a,

    E-Print Network [OSTI]

    Popov, Branko N.

    A Novel Electrodeposition Process for Plating Zn-Ni-Cd Alloys Hansung Kim,a, * Branko N. Popov Sciences Center, Albuquerque, New Mexico 87185-0834, USA Zn-Ni-Cd alloy was electrodeposited from in the literature.7-9 Typical nickel composition in the alloy is approximately 10%, and any further increase

  8. Recycling ZnTe, CdTe, and Other Compound Semiconductors by Ambipolar Electrolysis

    E-Print Network [OSTI]

    Osswald, Sebastian

    The electrochemical behavior of ZnTe and CdTe compound semiconductors dissolved in molten ZnCl[subscript 2] and equimolar CdCl[subscript 2]–KCl, respectively, was examined. In these melts dissolved Te is present as the ...

  9. Development of Prototype Pixellated PIN CdZnTe Detectors

    E-Print Network [OSTI]

    T. Narita; P. Bloser; J. Grindlay; R. Sudharsanan; C. Reiche; C. Stenstrom

    1998-06-12T23:59:59.000Z

    We report initial results from the design and evaluation of two pixellated PIN Cadmium Zinc Telluride detectors and an ASIC-based readout system. The prototype imaging PIN detectors consist of 4X4 1.5 mm square indium anode contacts with 0.2 mm spacing and a solid cathode plane on 10X10 mm CdZnTe substrates of thickness 2 mm and 5 mm. The detector readout system, based on low noise preamplifier ASICs, allows for parallel readout of all channels upon cathode trigger. This prototype is under development for use in future astrophysical hard X-ray imagers with 10-600 keV energy response. Measurements of the detector uniformity, spatial resolution, and spectral resolution will be discussed and compared with a similar pixellated MSM detector. Finally, a prototype design for a large imaging array is outlined.

  10. Strain effects and band parameters in MgO, ZnO, and CdO Qimin Yan,1

    E-Print Network [OSTI]

    deformation potentials for MgO, ZnO, and CdO in the wurtzite phase. To overcome the limitations of density equilibrium crystal structure. While ZnO crystal- izes in the wurtzite phase, MgO and CdO adopt the rocksalt phase. In spite of this complication wurtzite Zn1-xMgxO and Zn1-xCdxO alloys with low Mg or Cd

  11. FINAL REPORT OF RESEARCH ON CuxS/ (Cd,Zn)S PHOTOVOLTAIC SOLAR ENERGY CONVERTERS 3/77 - 9/79

    E-Print Network [OSTI]

    Chin, B.L.

    2013-01-01T23:59:59.000Z

    and (Cd,Zn)S/CuxS photovoltaic cells. The approach was tothe CuxS/(Cd,Zn)S photovoltaic cell in order to betterstudying CdS/CuxS photovoltaic cells, films prepared by the

  12. Multichannel CdZnTe Gamma Ray Spectrometer

    SciTech Connect (OSTI)

    F. P. Doty; C. L. Lingren; B. A. Apotovsky; J. Brunsch; J. F. Butler; T. Collins; R. L. Conwell; S. Friesenhahn; J. Gormley; B. Pi; S. Zhao (Digirad Corp., San Diego, CA); F. L. Augustine, Augustine Engineering, Encinitas, CA; B. A. Bennet; E. Cross; R. B. James (Sandia Nat'l. Labs.)

    1998-07-22T23:59:59.000Z

    A 3 cm{sup 3} multichannel gamma spectrometer for DOE applications is under development by Digirad Corporation. The device is based on a position sensitive detector packaged in a compact multi-chip module (MCM) with integrated readout circuitry. The modular, multichannel design will enable identification and quantitative analysis of radionuclides in extended sources, or sources containing low levels of activity. The MCM approach has the advantages that the modules are designed for imaging applications, and the sensitivity can be arbitrarily increased by increasing the number of pixels, i.e. adding modules to the instrument. For a high sensitivity probe, the outputs for each pixel can be corrected for gain and offset variations, and summed digitally. Single pixel results obtained with discrete low noise readout indicate energy resolution of 3 keV can be approached with currently available CdZnTe. The energy resolution demonstrated to date with MCMs for 511 keV gamma rays is 10 keV.

  13. Prototype Imaging Cd-Zn-Te Array Detector

    E-Print Network [OSTI]

    P. F. Bloser; T. Narita; J. E. Grindlay; K. Shah

    1998-01-15T23:59:59.000Z

    We describe initial results of our program to develop and test Cd-Zn-Te (CZT) detectors with a pixellated array readout. Our primary interest is in the development of relatively thick CZT detectors for use in astrophysical coded aperture telescopes with response extending over the energy range $\\sim 10-600$ keV. The coded aperture imaging configuration requires only relatively large area pixels (1-3 mm), whereas the desired high energy response requires detector thicknesses of at least 3-5 mm. We have developed a prototype detector employing a 10 x 10 x 5 mm CZT substrate and 4 x 4 pixel (1.5 mm each) readout with gold metal contacts for the pixels and continuous gold contact for the bias on the opposite detector face. This MSM contact configuration was fabricated by RMD and tested at Harvard for uniformity, efficiency and spatial as well as spectral resolution. We have developed an ASIC readout (IDE-VA-1) and analysis system and report results, including $\\sim 4$% (FWHM) energy resolution at 60 keV. A prototype design for a full imaging detector array is discussed.

  14. Synthesis and optical study of green light emitting polymer coated CdSe/ZnSe core/shell nanocrystals

    SciTech Connect (OSTI)

    Tripathi, S.K., E-mail: surya@pu.ac.in [Department of Physics, Center of Advanced Study in Physics, Panjab University, Chandigarh 160 014 (India); Sharma, Mamta [Department of Physics, Center of Advanced Study in Physics, Panjab University, Chandigarh 160 014 (India)

    2013-05-15T23:59:59.000Z

    Highlights: ? Synthesis of Polymer coated core CdSe and CdSe/ZnSe core/shell NCs. ? From TEM image, the spherical nature of CdSe and CdSe/ZnSe is obtained. ? Exhibiting green band photoemission peak at 541 nm and 549 nm for CdSe core and CdSe/ZnSe core/shell NCs. ? The shell thickness has been calculated by using superposition of quantum confinement energy model. - Abstract: CdSe/ZnSe Core/Shell NCs dispersed in PVA are synthesized by chemical method at room temperature. This is characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), UV/Vis spectra and photoluminescence spectroscopy (PL). TEM image shows the spherical nature of CdSe/ZnSe core/shell NCs. The red shift of absorption and emission peak of CdSe/ZnSe core/shell NCs as compared to CdSe core confirmed the formation of core/shell. The superposition of quantum confinement energy model is used for calculation of thickness of ZnSe shell.

  15. FINAL REPORT OF RESEARCH ON CuxS/ (Cd,Zn)S PHOTOVOLTAIC SOLAR ENERGY CONVERTERS 3/77 - 9/79

    E-Print Network [OSTI]

    Chin, B.L.

    2013-01-01T23:59:59.000Z

    S/(Cd,Zn)S PHOTOVOLTAIC SOLAR ENERGY CONVERTERS 3/77 - 9/79Research on Photovoltaic Solar Energy Converters CuxSI(Cd~

  16. Electronics System for the GammaTracker Handheld CdZnTe Detector

    SciTech Connect (OSTI)

    Myjak, Mitchell J.; Morris, Scott J.; Slaugh, Ryan W.; McCann, Jason M.; Kirihara, Leslie J.; Rohrer, John S.; Burghard, Brion J.; Seifert, Carolyn E.

    2007-12-31T23:59:59.000Z

    We are currently developing a handheld radioisotope identifier containing eighteen position-sensitive CdZnTe crystals. In addition to isotope identification, the device performs basic Compton imaging to determine the location of suspected sources. This paper gives an overview of the electronics system we have designed for this instrument. We use specialized application-specific integrated circuits to preprocess the outputs of each CdZnTe crystal. A low-power microprocessor running Windows CE drives the user interface and implements the isotope identification and directionality computations. Finally, we use a field-programmable gate array to perform the computationally intensive imaging tasks in real time.

  17. Absorption spectra of CdSe-ZnS core-shell quantum dots at high photon energies : experiment and modeling

    E-Print Network [OSTI]

    Ghosh, Sandip

    Absorption spectra of CdSe-ZnS core-shell quantum dots at high photon energies : experiment spectra of CdSe-ZnS core-shell quantum dot (QD) ensembles, with average core diameters ranging from 2.6 nm. In agreement with previous reports, the absorption coefficient at energies 1 eV above the effective bandgap

  18. Dissolved trace metals (Ni, Zn, Co, Cd, Pb, Al, and Mn) around the Crozet Islands, Southern Ocean

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    of trace elements such as Zn, Co, and Cd may be influenced by complexing ligands [e.g., Zn: Bruland, 1989; Ellwood and van den Berg, 2000; Co: Ellwood and van den Berg, 2001; Saito et al., 2004; Cd: Bruland, 1992

  19. Tunable mechanical and thermal properties of ZnS/CdS core/shell nanowires

    E-Print Network [OSTI]

    Mandal, Taraknath; Maiti, Prabal K

    2015-01-01T23:59:59.000Z

    Using all atom molecular dynamics (MD) simulations, we have studied the mechanical properties of ZnS/CdS core/shell nanowires. Our results show that the coating of a few atomic layer CdS shell on the ZnS nanowire leads to a significant change in the stiffness of the core/shell nanowires compared to the stiffness of pure ZnS nanowires. The binding energy between the core and shell region decreases due to the lattice mismatch at the core-shell interface. This reduction in binding energy plays an important role in determining the stiffness of a core/shell nanowire. We have also investigated the effects of the shell on the thermal conductivity and melting behavior of the nanowires.

  20. Upconversion Luminescence of Colloidal CdS and ZnCdS Semiconductor...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    luminescence is due to two-photon excitation. Citation: Ouyang J, JA Ripmeester, X Wu, D Kingston, K Yu, AG Joly, and W Chen.2007."Upconversion Luminescence of Colloidal CdS...

  1. Spectral photoresponse of ZnSe/GaAs(001) heterostructures with CdSe ultra-thin quantum well insertions

    SciTech Connect (OSTI)

    Valverde-Chávez, D. A.; Sutara, F.; Hernández-Calderón, I. [Physics Department, Cinvestav-IPN, Av. IPN 2508, 07360 México, DF (Mexico)

    2014-05-15T23:59:59.000Z

    We present a study of the spectral photoresponse (SPR) of ZnSe/GaAs(001) heterostructures for different ZnSe film thickness with and without CdSe ultra-thin quantum well (UTQW) insertions. We observe a significant increase of the SPR of heterostructures containing 3 monolayer thick CdSe UTQW insertions; these results encourage their use in photodetectors and solar cells.

  2. ZnO/Sn:In2O3 and ZnO/CdTe band offsets for extremely thin absorber...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ZnOSn:In2O3 and ZnOCdTe band offsets for extremely thin absorber photovoltaics . ZnOSn:In2O3 and ZnOCdTe band offsets for extremely thin absorber photovoltaics . Abstract: Band...

  3. Metastability in Pressure-Induced Structural Transformations of CdSe/ZnS Core/Shell Nanocrystals

    E-Print Network [OSTI]

    Rabani, Eran

    . In nanocrystals with thick shells, we furthermore observe a wurtzite to NiAs transformation, which does not occur on particles' size and shape.2-6 The wurtzite to rocksalt transformation in CdSe nanocrystals, for example wurtzite CdSe nanocrystals of 3 nm diameter (500 atoms), that have been epitaxially passivated with Zn

  4. HIGH TEMPERATURE LATTICE PARAMETERS OF ZnSiP2, ZnGeP2 AND CdGeP2 A. MILLER (*), R. G. HUMPHREYS and B. CHAPMAN

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    HIGH TEMPERATURE LATTICE PARAMETERS OF ZnSiP2, ZnGeP2 AND CdGeP2 A. MILLER (*), R. G. HUMPHREYS parameters from room temperature to 1.100 "C have been studied for the chalcopyrite semiconductors, ZnSiP2, ZnGeP2 and CdGeP2 using a high temperature X-ray camera. All three compounds show an increase

  5. Strain effects and band parameters in MgO, ZnO, and CdO Qimin Yan, Patrick Rinke, Momme Winkelnkemper, Abdallah Qteish, Dieter Bimberg et al.

    E-Print Network [OSTI]

    parameters) and strain deformation potentials for MgO, ZnO, and CdO in the wurtzite phase. To overcome family have the same equilib- rium crystal structure. While ZnO crystalizes in the wurtzite phase, MgO and CdO adopt the rocksalt phase. In spite of this complication wurtzite Zn1Ã?xMgxO and Zn1Ã?xCdxO alloys

  6. Reduction of surface leakage current by surface passivation of CdZn Te and other materials using hyperthermal oxygen atoms

    DOE Patents [OSTI]

    Hoffbauer, Mark A. (Los Alamos, NM); Prettyman, Thomas H. (Los Alamos, NM)

    2001-01-01T23:59:59.000Z

    Reduction of surface leakage current by surface passivation of Cd.sub.1-x Zn.sub.x Te and other materials using hyperthermal oxygen atoms. Surface effects are important in the performance of CdZnTe room-temperature radiation detectors used as spectrometers since the dark current is often dominated by surface leakage. A process using high-kinetic-energy, neutral oxygen atoms (.about.3 eV) to treat the surface of CdZnTe detectors at or near ambient temperatures is described. Improvements in detector performance include significantly reduced leakage current which results in lower detector noise and greater energy resolution for radiation measurements of gamma- and X-rays, thereby increasing the accuracy and sensitivity of measurements of radionuclides having complex gamma-ray spectra, including special nuclear materials.

  7. HAND-HELD GAMMA-RAY SPECTROMETER BASED ON HIGH-EFFICIENCY FRISCH-RING CdZnTe DETECTORS.

    SciTech Connect (OSTI)

    CUI,Y.

    2007-05-01T23:59:59.000Z

    Frisch-ring CdZnTe detectors have demonstrated good energy resolution, el% FWHM at 662 keV, and good efficiency for detecting gamma rays. This technique facilitates the application of CdZnTe materials for high efficiency gamma-ray detection. A hand-held gamma-ray spectrometer based on Frisch-ring detectors is being designed at Brookhaven National Laboratory. It employs an 8x8 CdZnTe detector array to achieve a high volume of 19.2 cm3, so that detection efficiency is significantly improved. By using the front-end ASICs developed at BNL, this spectrometer has a small profile and high energy resolution. The spectrometer includes signal processing circuit, digitization and storage circuit, high-voltage module, and USB interface. In this paper, we introduce the details of the system structure and report our test results with it.

  8. Structure and red shift of optical band gap in CdO–ZnO nanocomposite synthesized by the sol gel method

    SciTech Connect (OSTI)

    Mosquera, Edgar, E-mail: edemova@ing.uchile.cl [Laboratorio de Materiales a Nanoescala, Departamento de Ciencia de los Materiales, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Av. Tupper 2069, Santiago (Chile); Pozo, Ignacio del, E-mail: ignacio.dpf@gmail.com [Facultad de Ciencias Naturales, Matemáticas y del Medio Ambiente, Universidad Tecnológica Metropolitana, Av. José Pedro Alessandri 1242, Santiago (Chile); Morel, Mauricio, E-mail: mmorel@ing.uchile.cl [Laboratorio de Materiales a Nanoescala, Departamento de Ciencia de los Materiales, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Av. Tupper 2069, Santiago (Chile)

    2013-10-15T23:59:59.000Z

    The structure and the optical band gap of CdO–ZnO nanocomposites were studied. Characterization using X-ray diffraction (XRD), transmission electron microscopy (TEM) and diffuse reflectance spectroscopy (DRS) analysis confirms that CdO phase is present in the nanocomposites. TEM analysis confirms the formation of spheroidal nanoparticles and nanorods. The particle size was calculated from Debey–Sherrer?s formula and corroborated by TEM images. FTIR spectroscopy shows residual organic materials (aromatic/Olefinic carbon) from nanocomposites surface. CdO content was modified in the nanocomposites in function of polyvinylalcohol (PVA) added. The optical band gap is found to be red shift from 3.21 eV to 3.11 eV with the increase of CdO content. Photoluminescence (PL) measurements reveal the existence of defects in the synthesized CdO–ZnO nanocomposites. - Graphical abstract: Optical properties of ZnO, CdO and ZnO/CdO nanoparticles. Display Omitted - Highlights: • TEM analysis confirms the presence of spherical nanoparticles and nanorods. • The CdO phase is present in the nanocomposites. • The band gap of the CdO–ZnO nanocomposites is slightly red shift with CdO content. • PL emission of CdO–ZnO nanocomposite are associated to structural defects.

  9. First-principles study of electronic and optical properties in wurtzite Zn_{1-x}Cd_xO

    E-Print Network [OSTI]

    Zhang, X D; Li, W X; Liu, C L; 10.1063/1.2901033

    2012-01-01T23:59:59.000Z

    A first-principles study has been performed to evaluate the electronic and optical properties of wurtzite Zn1-xCdxO up to x=0.25. We have employed the Perdew-Burke-Ernzerhof (PBE) form of generalized gradient approximation within the framework of density functional theory (DFT). Calculations have been carried out in different configurations. With the increasing Cd concentrations, the band gap of Zn1-xCdxO is decreased due to the increase of s states in conduction band. The results of imaginary part of dielectric function indicate that the optical transition between O 2p states in the highest valence band and Zn 4s states in the lowest conduction band has shifted to low energy range as the Cd concentrations increase. Besides, the optical band gap decreases from 3.2 to 2.84 eV with increasing Cd concentrations from 0 to 0.25. Meanwhile, the bowing parameter b, which has been obtained by fitting the results of optical band gap, is about 1.21 eV. The optical constants of pure ZnO and Zn0.75Cd0.25O, such as optica...

  10. Polarization fields in (Zn,Cd)OZnO quantum well structures S. Kalusniak, S. Sadofev, J. Puls, H. J. Wnsche, and F. Henneberger*

    E-Print Network [OSTI]

    Wünsche, Hans-Jürgen "Ede"

    forced by the different crystalline structure of the binaries, wurtzite for ZnO and rocksalt for CdO. Epitaxial growth far from thermal equilibrium has made it possible to alloy ZnO with CdO in strict wurtzite direction of the QW structures is along the polar c axis of the wurtzite lattice. As a consequence, built

  11. Biologically programmed synthesis of core-shell CdSe/ZnS nanocrystalsw Shailendra Singh,ab

    E-Print Network [OSTI]

    Chen, Wilfred

    not only directs the nucleation of inorganic materials, but also controls the crystal structure and sizeBiologically programmed synthesis of core-shell CdSe/ZnS nanocrystalsw Shailendra Singh report of core-shell semiconductor nanocrystal synthesis using a peptide template. Type II

  12. Fermi level stabilization and band edge energies in Cd{sub x}Zn{sub 1?x}O alloys

    SciTech Connect (OSTI)

    Detert, Douglas M.; Tom, Kyle B.; Dubon, Oscar D. [Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Department of Materials Science and Engineering, University of California, Berkeley, California 94720 (United States); Battaglia, Corsin; Javey, Ali [Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, California 94720 (United States); Denlinger, Jonathan D. [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Lim, Sunnie H. N. [Environmental Energy Technologies Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Anders, André [Accelerator and Fusion Research Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Yu, Kin M.; Walukiewicz, Wladek [Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

    2014-06-21T23:59:59.000Z

    We have measured the band edge energies of Cd{sub x}Zn{sub 1?x}O thin films as a function of composition by three independent techniques: we determine the Fermi level stabilization energy by pinning the Fermi level with ion irradiation, measure the binding energy of valence band states and core levels by X-ray photoelectron spectroscopy, and probe shifts in the conduction band and valence band density of states using soft X-ray absorption and emission spectroscopy, respectively. The three techniques find consensus in explaining the origin of compositional trends in the optical-bandgap narrowing upon Cd incorporation in wurtzite ZnO and widening upon Zn incorporation in rocksalt CdO. The conduction band minimum is found to be stationary for both wurtzite and rocksalt alloys, and a significant upward rise of the valence band maximum accounts for the majority of these observed bandgap changes. Given these band alignments, alloy disorder scattering is found to play a negligible role in decreasing the electron mobility for all alloys. These band alignment details, combined with the unique optical and electrical properties of the two phase regimes, make CdZnO alloys attractive candidates for photoelectrochemical water splitting applications.

  13. Development of ZnNiCd coatings by pulse electrodeposition process Prabhu Ganesan, Swaminatha P. Kumaraguru, Branko N. Popov

    E-Print Network [OSTI]

    Popov, Branko N.

    Development of Zn­Ni­Cd coatings by pulse electrodeposition process Prabhu Ganesan, Swaminatha P form 22 August 2006 Available online 6 October 2006 Abstract A pulse electrodeposition process. An increase in average current density resulted in a decrease in both nickel and cadmium content in the alloy

  14. Polarimetric performance of a Laue lens gamma-ray CdZnTe focal plane prototype

    SciTech Connect (OSTI)

    Curado da Silva, R. M. [Departmento de Fisica, Universidade de Coimbra, P-3000 Coimbra (Portugal); Center for Space Radiations, Univesite Catholique de Louvain (Belgium); Caroli, E.; Stephen, J. B.; Schiavone, F.; Donati, A.; Ventura, G. [Istituto di Astrofisica Spaziale e Fisica Cosmica-Bologna, Via Gobetti 101, I-40129 Bologna (Italy); Pisa, A.; Auricchio, N.; Frontera, F. [Dipartimento di Fisica, Universita di Ferrara, Ferrara (Italy); Del Sordo, S. [Istituto di Astrofisica Spaziale e Fisica Cosmica-Palermo, Via Ugo La Malfa 153, 90146 Palermo (Italy); Honkimaeki, V. [European Synchrotron Radiation Facility, Grenoble (France); Trindade, A. M. F. [Departmento de Fisica, Universidade de Coimbra, P-3000 Coimbra (Portugal)

    2008-10-15T23:59:59.000Z

    A gamma-ray telescope mission concept [gamma ray imager (GRI)] based on Laue focusing techniques has been proposed in reply to the European Space Agency call for mission ideas within the framework of the next decade planning (Cosmic Vision 2015-2025). In order to optimize the design of a focal plane for this satellite mission, a CdZnTe detector prototype has been tested at the European Synchrotron Radiation Facility under an {approx}100% polarized gamma-ray beam. The spectroscopic, imaging, and timing performances were studied and in particular its potential as a polarimeter was evaluated. Polarization has been recognized as being a very important observational parameter in high energy astrophysics (>100 keV) and therefore this capability has been specifically included as part of the GRI mission proposal. The prototype detector tested was a 5 mm thick CdZnTe array with an 11x11 active pixel matrix (pixel area of 2.5x2.5 mm{sup 2}). The detector was irradiated by a monochromatic linearly polarized beam with a spot diameter of about 0.5 mm over the energy range between 150 and 750 keV. Polarimetric Q factors of 0.35 and double event relative detection efficiency of 20% were obtained. Further measurements were performed with a copper Laue monochromator crystal placed between the beam and the detector prototype. In this configuration we have demonstrated that a polarized beam does not change its polarization level and direction after undergoing a small angle (<1 deg.) Laue diffraction inside a crystal.

  15. Use of separate ZnTe interface layers to form ohmic contacts to p-CdTe films

    DOE Patents [OSTI]

    Gessert, T.A.

    1999-06-01T23:59:59.000Z

    A method of is disclosed improving electrical contact to a thin film of a p-type tellurium-containing II-VI semiconductor comprising: depositing a first undoped layer of ZnTe on a thin film of p-type tellurium containing II-VI semiconductor with material properties selected to limit the formation of potential barriers at the interface between the p-CdTe and the undoped layer, to a thickness sufficient to control diffusion of the metallic-doped ZnTe into the p-type tellurium-containing II-VI semiconductor, but thin enough to minimize affects of series resistance; depositing a second heavy doped p-type ZnTe layer to the first layer using an appropriate dopant; and depositing an appropriate metal onto the outer-most surface of the doped ZnTe layer for connecting an external electrical conductor to an ohmic contact. 11 figs.

  16. Enhanced photovoltaic performance of nanocrystalline CdTe/ZnO solar cells using sol-gel ZnO and positive bias treatment

    SciTech Connect (OSTI)

    MacDonald, B. I. [CSIRO Materials Science and Engineering, Bayview Avenue, Clayton, Victoria 3168 (Australia); School of Chemistry and Bio21 Institute, The University of Melbourne, Parkville, Victoria 3010 (Australia); Della Gaspera, E.; Watkins, S. E.; Jasieniak, J. J., E-mail: Jacek.Jasieniak@csiro.au [CSIRO Materials Science and Engineering, Bayview Avenue, Clayton, Victoria 3168 (Australia); Mulvaney, P. [School of Chemistry and Bio21 Institute, The University of Melbourne, Parkville, Victoria 3010 (Australia)

    2014-05-14T23:59:59.000Z

    The effect of doping and porosity of the n-type ZnO layer on the performance of solution-processed, sintered p-CdTe/n-ZnO nanocrystal photovoltaic (PV) devices is investigated. Amorphous sol-gel ZnO is found to be the best candidate with overall energy conversion efficiencies above 8% obtained if the ZnO is also indium doped. We demonstrate that when such PV devices are left under forward bias (in dark or light), the device efficiency values are raised to at least 9.8%, due to a substantially increased open-circuit voltage and fill-factor. This drastic enhancement is attributed to improved band alignment at the ITO/CdTe interface. The forward-bias treatment is slowly reversed over a period of days to weeks on standing under open circuit conditions, but is readily restored with further voltage treatment. The moderate processing conditions and high efficiency of such devices demonstrate that nanocrystal-based systems are a promising technology for photovoltaics.

  17. Thermal conductivity of Zn{sub 4{minus}x}Cd{sub x}Sb{sub 3} solid solutions

    SciTech Connect (OSTI)

    Caillat, T.; Borshchevsky, A.; Fleurial, J.P.

    1997-07-01T23:59:59.000Z

    {beta}-Zn{sub 4}Sb{sub 3} was recently identified at the Jet Propulsion Laboratory as a new high performance p-type thermoelectric material with a maximum dimensionless thermoelectric figure of merit ZT of 1.4 at a temperature of 673K. A usual approach, used for many state-of-the-art thermoelectric materials, to further improve ZT values is to alloy {beta}-Zn{sub 4}Sb{sub 3} with isostructural compounds because of the expected decrease in lattice thermal conductivity. The authors have grown Zn{sub 4{minus}x}Cd{sub x}Sb{sub 3} crystals with 0.2 {le} x < 1.2 and measured their thermal conductivity from 10 to 500K. The thermal conductivity values of Zn{sub 4{minus}x}Cd{sub x}Sb{sub 3} alloys are significantly lower than those measured for {beta}-Zn{sub 4}Sb{sub 3} and are comparable to its calculated minimum thermal conductivity. A strong atomic disorder is believed to be primarily at the origin of the very low thermal conductivity of these materials which are also fairly good electrical conductors and are therefore excellent candidates for thermoelectric applications.

  18. Energy Transfer Dynamics and Dopant Luminescence in Mn-Doped CdS/ZnS Core/Shell Nanocrystals

    E-Print Network [OSTI]

    Chen, Hsiang-Yun

    2012-11-13T23:59:59.000Z

    intensity calibration. A 370 nm light emitting diode was used as the excitation light source. . 32 Figure 9 Absorption spectra of Mn-doped CdS/ZnS nanocrystals with (sample 1, solid) and without (sample 2, dashed) Ostwald ripening with the same CdS core... with core size and shell thickness of 3.6 and ~1.8 nm, respectively. The luminescence spectra were taken using a CCD spectrometer (USB2000, Ocean Optics) without intensity calibration using a 370 nm light emitting diode as the excitation light source...

  19. Energy Transfer Dynamics and Dopant Luminescence in Mn-Doped CdS/ZnS Core/Shell Nanocrystals 

    E-Print Network [OSTI]

    Chen, Hsiang-Yun

    2012-11-13T23:59:59.000Z

    intensity calibration. A 370 nm light emitting diode was used as the excitation light source. . 32 Figure 9 Absorption spectra of Mn-doped CdS/ZnS nanocrystals with (sample 1, solid) and without (sample 2, dashed) Ostwald ripening with the same CdS core... with core size and shell thickness of 3.6 and ~1.8 nm, respectively. The luminescence spectra were taken using a CCD spectrometer (USB2000, Ocean Optics) without intensity calibration using a 370 nm light emitting diode as the excitation light source...

  20. FLEXIBLE CdTe SOLAR CELLS BY A LOW TEMPERATURE PROCESS ON ITO/ZnO COATED A. Salavei, I. Rimmaudo, F. Piccinelli1

    E-Print Network [OSTI]

    Romeo, Alessandro

    FLEXIBLE CdTe SOLAR CELLS BY A LOW TEMPERATURE PROCESS ON ITO/ZnO COATED POLYMERS A. Salavei, I will be discussed. Keywords: Flexible Substrate, CdTe, ITO, Laser Processing, Thin Film Solar Cell 1 INTRODUCTION Thin film solar cells deposited on a flexible substrate are easier to integrate in buildings; they also

  1. 4,4?-Bipyridine-aided synthesis and characterization of Zn(II) and Cd(II) 2-sulfoterephthalate complexes

    SciTech Connect (OSTI)

    Xiao, Shan-Shan [College of Chemistry, Beijing Normal University, Beijing 100875 (China); Li, Xin-Xin [Analytical and Testing Centre, Beijing Normal University, Beijing 100875 (China); Zheng, Xiang-Jun, E-mail: xjzheng@bnu.edu.cn [College of Chemistry, Beijing Normal University, Beijing 100875 (China); Jia, Tian-Jing; Jin, Lin-Pei [College of Chemistry, Beijing Normal University, Beijing 100875 (China)

    2013-09-15T23:59:59.000Z

    Six d{sup 10} complexes, [Zn{sub 1.5}(stp)(bpy){sub 0.5}(H{sub 2}O){sub 2}]·0.5H{sub 2}O (1), Cd{sub 1.5}(stp)(bpy){sub 0.5}(H{sub 2}O){sub 2} (2), [Cd{sub 1.5}(stp)(bpy)(H{sub 2}O)]·H{sub 2}O (3), [Zn{sub 0.5}(bpy){sub 0.5}(H{sub 2}O){sub 2}][Zn(stp)(bpy)(H{sub 2}O)]·0.5H{sub 2}O (4), Cd{sub 3}(stp){sub 2}(bpy){sub 3}(H{sub 2}O){sub 3} (5), Hbpy·[Zn{sub 0.5}(bpy)(H{sub 2}O){sub 2}][Zn{sub 0.5}(stp)(H{sub 2}O)]·H{sub 2}O (6) based on 2-sulfoterephthalate (stp{sup 3?}) and 4,4?-bipyridine (bpy) have been synthesized under hydro/solvo-thermal conditions and structurally characterized. Complex 1 exhibits a three-fold interpenetrated 3D porous architecture. Complexes 2 and 3 possess helices with different chirality arranging alternately. 4 and 6 are addition compounds, which compose of complex cation and complex anion. Complex 5 features a 3D layer-pillar framework in which a (4, 4) grid layer is constructed by stp{sup 3?} ligands and Cd(II) ions, and the layers are further connected by bpy pillars. The solid-state luminescent properties of the coordination polymers have also been investigated. - Graphical abstract: Display Omitted - Highlights: • Complexes 1–3 possess helices with different chirality arranging alternately. • The structural diversity can be attributed to various coordination modes of ligands. • The formation of helical structure is related to the adjacent carboxyl and sulfonate groups. • Bpy exhibits three roles: bridge, hydrogen bonding acceptor, and template.

  2. Pulse-shape discrimination of surface events in CdZnTe detectors for the COBRA experiment

    E-Print Network [OSTI]

    Matthew Fritts; Jan Tebrügge; Jürgen Durst; Joachim Ebert; Claus Gößling; Thomas Göpfert; Daniel Gehre; Caren Hagner; Nadine Heidrich; Michael Homann; Tobias Köttig; Till Neddermann; Christian Oldorf; Thomas Quante; Silke Rajek; Oscar Reinecke; Oliver Schulz; Jan Timm; Björn Wonsak; Kai Zuber

    2014-01-23T23:59:59.000Z

    Events near the cathode and anode surfaces of a coplanar grid CdZnTe detector are identifiable by means of the interaction depth information encoded in the signal amplitudes. However, the amplitudes cannot be used to identify events near the lateral surfaces. In this paper a method is described to identify lateral surface events by means of their pulse shapes. Such identification allows for discrimination of surface alpha particle interactions from more penetrating forms of radiation, which is particularly important for rare event searches. The effectiveness of the presented technique in suppressing backgrounds due to alpha contamination in the search for neutrinoless double beta decay with the COBRA experiment is demonstrated.

  3. Electrically driven single photon emission from a CdSe/ZnSSe single quantum dot at 200?K

    SciTech Connect (OSTI)

    Quitsch, Wolf; Kümmell, Tilmar; Bacher, Gerd [Werkstoffe der Elektrotechnik and CENIDE, Universität Duisburg-Essen, Bismarckstraße 81, 47057 Duisburg (Germany); Gust, Arne; Kruse, Carsten; Hommel, Detlef [Institut für Festkörperphysik, Universität Bremen, Otto-Hahn-Allee 1, 28334 Bremen (Germany)

    2014-09-01T23:59:59.000Z

    High temperature operation of an electrically driven single photon emitter based on a single epitaxial quantum dot is reported. CdSe/ZnSSe/MgS quantum dots are embedded into a p-i-n diode architecture providing almost background free excitonic and biexcitonic electroluminescence from individual quantum dots through apertures in the top contacts. Clear antibunching with g{sup 2}(??=?0)?=?0.28?±?0.20 can be tracked up to T?=?200?K, representing the highest temperature for electrically triggered single photon emission from a single quantum dot device.

  4. A study of the timing properties of Cd{sub 0.9}Zn{sub 0.1}Te

    SciTech Connect (OSTI)

    Parnham, K.B.; Eissler, E.E.; Jovanovic, S.; Lynn, K.G.

    1995-12-31T23:59:59.000Z

    CdZnTe has become a material of great interest in the field of X- and {gamma}-ray imaging, and shows great promise as a highly efficient, room-temperature operation detector. However, data on the timing resolution obtainable with this material is scarce. It is known that CdZnTe, in common with all compound semi-conductors, gives pulses of varying rise-time depending on the interaction location, hence causing a broadening of the time spectrum. We therefore assembled and characterized an appropriate electronic measuring set-up and took data with 2 different sets of detectors, varying the experimental parameters such as bias voltage, threshold and temperature during the course of the experiment. The results obtained with planar detectors of 9 mm{sup 2} {times} 2 mm thick were superior to the results obtained with detectors of 25 mm{sup 2} {times} 10 mm thick, even when the difference in effective bias field strength is considered. Timing resolutions of 5.3 ns and 20.9 ns (FWHM) respectively were obtained. Reducing the temperature to 0{degree}C reduced the resolution to 4.5 ns, thereby indicating that the performance is limited by signal-to-noise ratio considerations.

  5. Voltage-induced electroluminescence characteristics of hybrid light-emitting diodes with CdSe/Cd/ZnS core-shell nanoparticles embedded in a conducting polymer on plastic substrates

    SciTech Connect (OSTI)

    Kwak, Kiyeol; Cho, Kyoungah, E-mail: chochem@korea.ac.kr, E-mail: sangsig@korea.ac.kr; Kim, Sangsig, E-mail: chochem@korea.ac.kr, E-mail: sangsig@korea.ac.kr [Department of Electrical Engineering, Korea University, Seoul 136-713 (Korea, Republic of)] [Department of Electrical Engineering, Korea University, Seoul 136-713 (Korea, Republic of)

    2014-03-10T23:59:59.000Z

    We investigate the electroluminescence (EL) characteristics of a hybrid light-emitting diode (HyLED) with an emissive layer comprised of CdSe/Cd/ZnS core-shell nanoparticles (NPs) embedded in poly(9,9-di-n-octylfluorenyl-2,7-diyl) (PFO) on a plastic substrate. The EL characteristics change dramatically with increasing of the biased voltage. At low voltages, recombination of electrons and holes occurs only in the PFO film because of poor charge transfer in the PFO-CdSe/Cd/ZnS NPs composite film, while the color of the light-emitting from the HyLED changes from blue to red as the biased voltage increases from 7.5 to 17.5?V. We examine and discuss the mechanism of this color tunability.

  6. Optically pumped quantum-dot Cd(Zn)Se/ZnSe laser and microchip converter for yellow-green spectral region

    SciTech Connect (OSTI)

    Lutsenko, E V; Voinilovich, A G; Rzheutskii, N V; Pavlovskii, V N; Yablonskii, G P; Sorokin, S V; Gronin, S V; Sedova, I V; Kop'ev, Petr S; Ivanov, Sergei V; Alanzi, M; Hamidalddin, A; Alyamani, A

    2013-05-31T23:59:59.000Z

    The room temperature laser generation in the yellow-green ({lambda} = 558.5-566.7 nm) spectral range has been demonstrated under optical pumping by a pulsed nitrogen laser of Cd(Zn)Se/ZnSe quantum dot heterostructures. The maximum achieved laser wavelength was as high as {lambda} = 566.7 nm at a laser cavity length of 945 {mu}m. High values of both the output pulsed power (up to 50 W) and the external differential quantum efficiency ({approx}60%) were obtained at a cavity length of 435 {mu}m. Both a high quality of the laser heterostructure and a low lasing threshold ({approx}2 kW cm{sup -2}) make it possible to use a pulsed InGaN laser diode as a pump source. A laser microchip converter based on this heterostructure has demonstrated a maximum output pulse power of {approx}90 mW at {lambda} = 560 nm. The microchip converter was placed in a standard TO-18 (5.6 mm in diameter) laser diode package. (semiconductor lasers. physics and technology)

  7. Abstract --An experimental small animal PET using two 3-D position sensitive CdZnTe detectors was developed and tested.

    E-Print Network [OSTI]

    He, Zhong

    Abstract -- An experimental small animal PET using two 3-D position sensitive CdZnTe detectors scattering angle reconstruction are reported and discussed. I. INTRODUCTION onventional PET systems use, for molecular imaging and drug development using high resolution PET is gaining more and more interests. One

  8. Use of high-granularity position sensing to correct response non-uniformities of CdZnTe detectors

    SciTech Connect (OSTI)

    Bolotnikov, A. E., E-mail: bolotnik@bnl.gov; Camarda, G. S.; Cui, Y.; De Geronimo, G.; Fried, J.; Hossain, A.; Mahler, G.; Maritato, M.; Marshall, M.; Roy, U.; Vernon, E.; Yang, G.; James, R. B. [Department of Non-proliferation and National Security, Brookhaven National Laboratory, Upton, New York 11793-5000 (United States); Lee, K. [Korea University, 161 Jeongneung-ro, Seongbuk-gu, Seoul, 136-855 (Korea, Republic of); Petryk, M. [State University of New York at Binghamton, Binghamton, New York 13902 (United States)

    2014-06-30T23:59:59.000Z

    CdZnTe (CZT) is a promising medium for room-temperature gamma-ray detectors. However, the low production yield of acceptable quality crystals hampers the use of CZT detectors for gamma-ray spectroscopy. Significant efforts have been directed towards improving quality of CZT crystals to make them generally available for radiation detectors. Another way to address this problem is to implement detector designs that would allow for more accurate and predictable correction of the charge loss associated with crystal defects. In this work, we demonstrate that high-granularity position-sensitive detectors can significantly improve the performance of CZT detectors fabricated from CZT crystals with wider acceptance boundaries, leading to an increase of their availability and expected decrease in cost.

  9. An effect of the networks of the subgrain boundaries on spectral responses of thick CdZnTe detectors

    SciTech Connect (OSTI)

    Bolotnikov, A.; Butcher, J.; Camarda, G.; Cui, Y.; Egarievwe, S.; Fochuk, P.; Gul,R.; Hamade, M.; Hossain, A.; Kim, K.; Kopach,O.; Petryk, M.; Raghothamachar, B.; Yang, G.; and James, R.B.

    2011-08-12T23:59:59.000Z

    CdZnTe (CZT) crystals used for nuclear-radiation detectors often contain high concentrations of subgrain boundaries and networks of poligonized dislocations that can significantly degrade the performance of semiconductor devices. These defects exist in all commercial CZT materials, regardless of their growth techniques and their vendor. We describe our new results from examining such detectors using IR transmission microscopy and white X-ray beam diffraction topography. We emphasize the roles on the devices performances of networks of subgrain boundaries with low dislocation densities, such as poligonized dislocations and mosaic structures. Specifically, we evaluated their effects on the gamma-ray responses of thick, >10 mm, CZT detectors. Our findings set the lower limit on the energy resolution of CZT detectors containing dense networks of subgrain boundaries, and walls of dislocations.

  10. Real-structure effects: Band gaps of Mg_xZn_{1-x}O, Cd_xZn_{1-x}O, and n-type ZnO from ab-initio calculations

    SciTech Connect (OSTI)

    Schleife, A; Bechstedt, F

    2012-02-15T23:59:59.000Z

    Many-body perturbation theory is applied to compute the quasiparticle electronic structures and the optical-absorption spectra (including excitonic effects) for several transparent conducting oxides. We discuss HSE+G{sub 0}W{sub 0} results for band structures, fundamental band gaps, and effective electron masses of MgO, ZnO, CdO, SnO{sub 2}, SnO, In{sub 2}O{sub 3}, and SiO{sub 2}. The Bethe-Salpeter equation is solved to account for excitonic effects in the calculation of the frequency-dependent absorption coefficients. We show that the HSE+G{sub 0}W{sub 0} approach and the solution of the Bethe-Salpeter equation are very well-suited to describe the electronic structure and the optical properties of various transparent conducting oxides in good agreement with experiment.

  11. A series of M-M' heterometallic coordination polymers: syntheses, structures and surface photoelectric properties (M=Ni/Co, M'=Cd/Zn)

    SciTech Connect (OSTI)

    Li, Lei [School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian 116029 (China); Niu, Shu-Yun, E-mail: syniu@sohu.co [School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian 116029 (China); Jin, Jing; Meng, Qin; Chi, Yu-Xian; Xing, Yong-Heng [School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian 116029 (China); Zhang, Guang-Ning [Institute of Chemistry for Functionalized Materials, Liaoning Normal University, Dalian 116029 (China)

    2011-05-15T23:59:59.000Z

    Four new heterometallic polymers, [NiCd(mal){sub 2}(H{sub 2}O){sub 2}]n.2nH{sub 2}O 1, [NiZn{sub 2}(Hcit){sub 2}(H{sub 2}O){sub 2}]n 2, [CoCd{sub 2}(Hcit){sub 2}(H{sub 2}O){sub 2}]n 3, [CoZn{sub 2}(Hcit){sub 2}(H{sub 2}O){sub 2}]n 4 (H{sub 2}mal=malonic acid, H{sub 4}cit=citric acid) were synthesized and characterized. The photoelectric properties of the polymers were discussed by the surface photovoltage spectroscopy (SPS). The structural analyses indicate 1 is a Ni-Cd heterometallic polymer with 3D structure bridged by the mal{sup 2-} group. 2-4 are all heterometallic polymers with 2D structures bridged by the Hcit{sup 3-} group. The results of SPS for the four polymers reveal that there are wide photovoltage response bands in the range of 300-800 nm, which indicates that they all possess photoelectric conversion properties. By the introduction of the other metals, the SPS of heterometallic polymers are broadened obviously than the SPS of monometallic complexes. Moreover, the relationships between SPS and UV-Vis absorption spectra have been discussed. -- Graphical Abstract: Four heterometallic polymers, Ni-Cd, Ni-Zn, Co-Cd, Co-Zn, were synthesized and characterized. The photoelectric properties of heterometallic polymers were discussed by SPS. The introduction of heterometallic ions will broaden the SPS of corresponded monometallic complexes. Display Omitted highlights: > Four new heterometallic coordination polymers were reported. > The surface photoelectric properties of heterometallic polymers were studied by SPS. > They all possess photoelectric conversion properties. > The SPS of heterometallic polymers are broadened than that of monometallic complexes.

  12. Development of ZnTe:Cu Contacts for CdTe Solar Cells: Cooperative Research and Development Final Report, CRADA Number CRD-08-320

    SciTech Connect (OSTI)

    Dhere, R.

    2012-04-01T23:59:59.000Z

    The main focus of the work at NREL was on the development of Cu-doped ZnTe contacts to CdTe solar cells in the substrate configuration. The work performed under the CRADA utilized the substrate device structure used at NREL previously. All fabrication was performed at NREL. We worked on the development of Cu-doped ZnTe as well as variety of other contacts such as Sb-doped ZnTe, CuxTe, and MoSe2. We were able to optimize the contacts to improve device parameters. The improvement was obtained primarily through increasing the open-circuit voltage, to values as high as 760 mV, leading to device efficiencies of 7%.

  13. CD

    Annual Energy Outlook 2013 [U.S. Energy Information Administration (EIA)]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33 111 1,613 122 40Coal Stocks at CommercialDecade Year-0Proved ReservesBuildingsm 3 (D CD ^ Q) r*

  14. COMPARISON OF TRAP STATES BETWEEN CIGSS/CdS/ZnO AND Cd PE CIGSS/ZnO CELLS P.K. Johnson, A.O. Pudov, J.R. Sites

    E-Print Network [OSTI]

    Sites, James R.

    (CIGS) thin films were treated in Cd solutions (Cd PE treatment) yielded solar cells with efficiencies surface can produce a cell comparable to the best CdS/CIGS cells. We extend this work to include CIGSS Defects - 3 1. INTRODUCTION Polycrystalline CIGS thin film photovoltaic cells are known for their high

  15. Strain effects and band parameters in MgO, ZnO and CdO Qimin Yan,1

    E-Print Network [OSTI]

    ) would give a bandgap of 3.4 eV for wurtzite ZnO and that all previous reports of a significantly lower(cLDA) bandgap in wurtzite ZnO. The band convergence is indeed slow and the bandgap only converges when0W0@OEPx(cLDA) bandgap of wurtzite ZnO at the experimental lattice parameters on the number

  16. Near-Infrared Photoluminescence Enhancement in Ge/CdS and Ge/ZnS Core/Shell Nanocrystals: Utilizing IV/II-VI Semiconductor Epitaxy

    SciTech Connect (OSTI)

    Guo, Yijun [Ames Laboratory; Rowland, Clare E [Argonne National Laboratory; Schaller, Richard D [Argonne National Laboratory; Vela, Javier [Ames Laboratory

    2014-08-26T23:59:59.000Z

    Ge nanocrystals have a large Bohr radius and a small, size-tunable band gap that may engender direct character via strain or doping. Colloidal Ge nanocrystals are particularly interesting in the development of near-infrared materials for applications in bioimaging, telecommunications and energy conversion. Epitaxial growth of a passivating shell is a common strategy employed in the synthesis of highly luminescent II–VI, III–V and IV–VI semiconductor quantum dots. Here, we use relatively unexplored IV/II–VI epitaxy as a way to enhance the photoluminescence and improve the optical stability of colloidal Ge nanocrystals. Selected on the basis of their relatively small lattice mismatch compared with crystalline Ge, we explore the growth of epitaxial CdS and ZnS shells using the successive ion layer adsorption and reaction method. Powder X-ray diffraction and electron microscopy techniques, including energy dispersive X-ray spectroscopy and selected area electron diffraction, clearly show the controllable growth of as many as 20 epitaxial monolayers of CdS atop Ge cores. In contrast, Ge etching and/or replacement by ZnS result in relatively small Ge/ZnS nanocrystals. The presence of an epitaxial II–VI shell greatly enhances the near-infrared photoluminescence and improves the photoluminescence stability of Ge. Ge/II–VI nanocrystals are reproducibly 1–3 orders of magnitude brighter than the brightest Ge cores. Ge/4.9CdS core/shells show the highest photoluminescence quantum yield and longest radiative recombination lifetime. Thiol ligand exchange easily results in near-infrared active, water-soluble Ge/II–VI nanocrystals. We expect this synthetic IV/II–VI epitaxial approach will lead to further studies into the optoelectronic behavior and practical applications of Si and Ge-based nanomaterials.

  17. Band alignments of different buffer layers (CdS, Zn(O,S), and In{sub 2}S{sub 3}) on Cu{sub 2}ZnSnS{sub 4}

    SciTech Connect (OSTI)

    Yan, Chang; Liu, Fangyang; Song, Ning; Hao, Xiaojing, E-mail: xj.hao@unsw.edu.au [Australian Centre for Advanced Photovoltaics, School of Photovoltaic and Renewable Energy Engineering, University of New South Wales, Sydney, New South Wales 2052 (Australia); Ng, Boon K.; Stride, John A. [School of Chemistry, University of New South Wales, Sydney, New South Wales 2052 (Australia); Tadich, Anton [Australian Synchrotron, Melbourne, Victoria 3168 (Australia)

    2014-04-28T23:59:59.000Z

    The heterojunctions of different n-type buffers, i.e., CdS, Zn(O,S), and In{sub 2}S{sub 3} on p-type Cu{sub 2}ZnSnS{sub 4} (CZTS) were investigated using X-ray Photoelectron Spectroscopy (XPS) and Near Edge X-ray Absorption Fine Structure (NEXAFS) Measurements. The band alignment of the heterojunctions formed between CZTS and the buffer materials was carefully measured. The XPS data were used to determine the Valence Band Offsets (VBO) of different buffer/CZTS heterojunctions. The Conduction Band Offset (CBO) was calculated indirectly by XPS data and directly measured by NEXAFS characterization. The CBO of the CdS/CZTS heterojunction was found to be cliff-like with CBO{sub XPS}?=??0.24?±?0.10?eV and CBO{sub NEXAFS}?=??0.18?±?0.10?eV, whereas those of Zn(O,S) and In{sub 2}S{sub 3} were found to be spike-like with CBO{sub XPS}?=?0.92?±?0.10?eV and CBO{sub NEXAFS}?=?0.87?±?0.10?eV for Zn(O,S)/CZTS and CBO{sub XPS}?=?0.41?±?0.10?eV for In{sub 2}S{sub 3}/CZTS, respectively. The CZTS photovoltaic device using the spike-like In{sub 2}S{sub 3} buffer was found to yield a higher open circuit voltage (Voc) than that using the cliff-like CdS buffer. However, the CBO of In{sub 2}S{sub 3}/CZTS is slightly higher than the optimum level and thus acts to block the flow of light-generated electrons, significantly reducing the short circuit current (Jsc) and Fill Factor (FF) and thereby limiting the efficiency. Instead, the use of a hybrid buffer for optimization of band alignment is proposed.

  18. New ternary phosphides and arsenides. Syntheses, crystal structures, physical properties of Eu{sub 2}ZnP{sub 2}, Eu{sub 2}Zn{sub 2}P{sub 3} and Eu{sub 2}Cd{sub 2}As{sub 3}

    SciTech Connect (OSTI)

    Wang, Jian [State Key Laboratory of Crystal Materials, Institute of Crystal Materials, Shandong University, Jinan, Shandong 250100 (China); Xia, Sheng-Qing, E-mail: shqxia@sdu.edu.cn [State Key Laboratory of Crystal Materials, Institute of Crystal Materials, Shandong University, Jinan, Shandong 250100 (China); Tao, Xu-Tang [State Key Laboratory of Crystal Materials, Institute of Crystal Materials, Shandong University, Jinan, Shandong 250100 (China); Schäfer, Marion C. [Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716 (United States); Bobev, Svilen, E-mail: bobev@udel.edu [Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716 (United States)

    2013-09-15T23:59:59.000Z

    Three new europium pnictides Eu{sub 2}ZnP{sub 2}, Eu{sub 2}Zn{sub 2}P{sub 3} and Eu{sub 2}Cd{sub 2}As{sub 3} have been synthesized and their structures were determined by single-crystal X-ray diffraction. Eu{sub 2}ZnP{sub 2} is isotypic with Yb{sub 2}CdSb{sub 2} (Cmc2{sub 1} (No. 36); cell parameters a=4.1777(7) Å, b=15.925(3) Å, c=7.3008(12) Å), while the latter two compounds crystallize with the Ba{sub 2}Cd{sub 2}Sb{sub 3} structure type (C2/m (No. 12); cell parameters a=15.653(5)/16.402(1) Å, b=4.127(1)/4.445(4) Å, c=11.552(4)/12.311(1) Å and ?=126.647(4)/126.515(7)° for Eu{sub 2}Zn{sub 2}P{sub 3} and Eu{sub 2}Cd{sub 2}As{sub 3}, respectively). Magnetic susceptibility measurements in the interval 5–300 K confirm paramagnetic behavior and effective magnetic moments characteristic of Eu{sup 2+} ([Xe] 4f{sup 7}) ground states. Temperature-dependent electrical conductivity measurements also prove that Eu{sub 2}Cd{sub 2}As{sub 3} is a semiconducting compound with a narrow band gap of 0.059 eV below 100 K. According to TG/DSC analyses, Eu{sub 2}Cd{sub 2}As{sub 3} starts to decompose at about 950 K. - Graphical abstract: A polyhedral view of the crystal structure of new pnictides Eu{sub 2}T{sub 2}Pn{sub 3} (T=Zn or Cd; Pn=P or As). Display Omitted - Highlights: • Three new ternary pnictide Zintl compounds, Eu{sub 2}ZnP{sub 2}, Eu{sub 2}Zn{sub 2}P{sub 3} and Eu{sub 2}Cd{sub 2}As{sub 3}, have been synthesized and characterized. • The europium cations are divalent and ferromagnetically coupled in both Eu{sub 2}Zn{sub 2}P{sub 3} and Eu{sub 2}Cd{sub 2}As{sub 3}. • Eu{sub 2}Cd{sub 2}As{sub 3} has a very small band gap of 0.06 eV and starts to decompose over 950 K.

  19. PROPERTIES OF Cd and Zn PARTIAL ELECTROLYTE TREATED CIGS SOLAR CELLS K. Ramanathan, F.S. Hasoon, S. Smith, A. Mascarenhas, H. Al-Thani, J. Alleman, H.S. Ullal and J. Keane

    E-Print Network [OSTI]

    Sites, James R.

    PROPERTIES OF Cd and Zn PARTIAL ELECTROLYTE TREATED CIGS SOLAR CELLS K. Ramanathan, F.S. Hasoon, SS/CIGS interface has been treated as a "non- interacting," or abrupt junction. There are a few reports [3 changes such as those mentioned above have not been adequately treated in further analysis of the junction

  20. Drift time variations in CdZnTe detectors measured with alpha-particles: Their correlation with the detector’s responses

    SciTech Connect (OSTI)

    Bolotnikov A. E.; Butcher, J.; Hamade, M.; Petryk, M.; Bolotnikov, A.; Camarda, G.; Cui, Y.; Hossain, A.; Kim, K.; Yang, G.; and James, R.

    2012-05-14T23:59:59.000Z

    Homogeneity of properties related to material crystallinity is a critical parameter for achieving high-performance CdZnTe (CZT) radiation detectors. Unfortunately, this requirement is not always satisfied in today's commercial CZT material due to high concentrations of extended defects, in particular subgrain boundaries, which are believed to be part of the causes hampering the energy resolution and efficiency of CZT detectors. In the past, the effects of subgrain boundaries have been studied in Si, Ge and other semiconductors. It was demonstrated that subgrain boundaries tend to accumulate secondary phases and impurities causing inhomogeneous distributions of trapping centers. It was also demonstrated that subgrain boundaries result in local perturbations of the electric field, which affect the carrier transport and other properties of semiconductor devices. The subgrain boundaries in CZT material likely behave in a similar way, which makes them responsible for variations in the electron drift time and carrier trapping in CZT detectors. In this work, we employed the transient current technique to measure variations in the electron drift time and related the variations to the device performances and subgrain boundaries, whose presence in the crystals were confirmed with white beam X-ray diffraction topography and infrared transmission microscopy.

  1. SQCD, Superconducting Gaps and Cyclic RG Flows

    E-Print Network [OSTI]

    Alexander Gorsky

    2012-02-20T23:59:59.000Z

    We consider the relation between the \\Omega -deformed N=2 SQCD with the single deformation parameter and integrable models of the BCS-like superconductivity. It is argued that the vortex string worldsheet theory is related to the Russian Doll(RD) model of the truncated BCS superconductivity. We argue that the \\Omega -deformed gauge theory manifests the interesting cyclic RG behavior with the period of the RG cycle proportional to \\epsilon^{-1}. The deformed gauge theory can develop several non-perturbative scales. We conjecture on the monopole bound state interpretation of the Efimov tower.

  2. Bright three-band white light generated from CdSe/ZnSe quantum dot-assisted Sr{sub 3}SiO{sub 5}:Ce{sup 3+},Li{sup +}-based white light-emitting diode with high color rendering index

    SciTech Connect (OSTI)

    Jang, Ho Seong; Kwon, Byoung-Hwa; Jeon, Duk Young [Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, 373-1, Guseong-dong, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Yang, Heesun [Department of Materials Science and Engineering, Hongik University, 72-1, Sangsu-dong, Mapo-gu, Seoul 121-791 (Korea, Republic of)

    2009-10-19T23:59:59.000Z

    In this study, bright three-band white light was generated from the CdSe/ZnSe quantum dot (QD)-assisted Sr{sub 3}SiO{sub 5}:Ce{sup 3+},Li{sup +}-based white light-emitting diode (WLED). The CdSe/ZnSe core/shell structure was confirmed by energy dispersive x-ray spectroscopy and x-ray photoelectron spectroscopy. The CdSe/ZnSe QDs showed high quantum efficiency (79%) and contributed to the high luminous efficiency ({eta}{sub L}) of the fabricated WLED. The WLED showed bright natural white with excellent color rendering property ({eta}{sub L}=26.8 lm/W, color temperature=6140 K, and color rendering index=85) and high stability against the increase in forward bias currents from 20 to 70 mA.

  3. Enrichment of the Superheavy Element Rg in Natural Au

    E-Print Network [OSTI]

    A. Marinov; A. Pape; D. Kolb; L. Halicz; I. Segal; N. Tepliakov; Y. Kashiv; R. Brandt

    2010-11-30T23:59:59.000Z

    Based on the observation of the long-lived isotopes 261Rg and 265Rg (Z = 111, t(1/2) >= 10^(8) y) in natural Au, an experiment was performed to enrich Rg in 99.999% Au. 16 mg of Au were heated in vacuum for two weeks at a temperature of 1127 deg. C (63 deg. C above the melting point of Au). The content of 197Au and 261Rg in the residue was studied with high resolution inductively coupled plasma-sector field mass spectrometry (ICP-SFMS). The residue of Au was 3x10^(-6) of its original quantity. The recovery of Rg was a few percent. The abundance of Rg compared to Au in the enriched solution was about 2x10^(-6), which is a three to four orders of magnitude enrichment. It is concluded that the evaporation rate of Rg from an Au matrix in vacuum at 63 deg. C above the Au melting point is lower than that of Au. This experiment reinforces our first observation of Rg in a terrestrial material. As before it is concluded that a long-lived isomeric state exists in 261Rg and that it probably belongs to a new class of isomeric states, namely high spin super- or hyperdeformed isomeric states.

  4. Experimental investigation of exciton-LO-phonon couplings in CdSe/ZnS core/shell nanorods Holger Lange,1,* Mikhail Artemyev,2

    E-Print Network [OSTI]

    Nabben, Reinhard

    in the field of optoelectronics. CdSe nanorods have interest- ing properties, which lead to possible trioctylphosphine selenide in trioctylphos- phine oxide in the presence of hexadecylphosphonic acid as a surface- lected nanorod samples in a second step in a hexadecilamine/ trioctylphosphine oxide reaction mixture

  5. ENVIRONMENTAL HEALTH SCIENCES Plan Requirements Campus: UMICH RG = Requirement Group

    E-Print Network [OSTI]

    Shyy, Wei

    ENVIRONMENTAL HEALTH SCIENCES Plan Requirements Campus: UMICH RG = Requirement Group Career: GPH RQ = Requirement Program: 01848 LN = Line Plan: 3200MPH RG 5298 ENVIRONMENTAL HEALTH SCIENCES REQUIREMENTS, 643, 653, 675, 677 or 695 LN 0030 - Environmental Health Sciences: EHS 501, 506, 507 or 508 LN 0040

  6. RG&E (Gas)- Commercial and Industrial Efficiency Program

    Broader source: Energy.gov [DOE]

    NYSEG and RG&E offer rebates to non-residential customers installing energy efficiency equipment that pay a natural gas Systems Benefits Charge (SBC). Both prescriptive rebates and custom...

  7. RG&E (Electric)- Commercial and Industrial Efficiency Program

    Broader source: Energy.gov [DOE]

    NYSEG and RG&E offer rebates to non-residential customers installing energy efficient equipment that have an electricity Systems Benefits Charge (SBC) included in their energy bills. Both...

  8. RG&E (Electric)- Small Business Lighting Retrofit Program

    Broader source: Energy.gov [DOE]

    RG&E offers a lighting incentive program designed to serve small business customers with a demand of 100 kilowatts (kW) or less. These small business customers may schedule a free energy...

  9. RG&E (Gas)- Residential Efficiency Program (New York)

    Broader source: Energy.gov [DOE]

    RG&E is offering residential natural gas customers rebates for installing energy efficient equipment. Customers can complete one rebate application for multiple pieces of equipment as long as...

  10. REACTOR WWR-M R.G. Pikulik

    E-Print Network [OSTI]

    Titov, Anatoly

    25 REACTOR WWR-M R.G. Pikulik The reactor WWR-M of the Petersburg Nuclear Physics Institute (PNPI, 1959, is the first im- plemented modernization version of the project of 2 MW serial reactor WWR-S developed in the USSR. The purpose of modernization was to develop a then modern reactor based

  11. Electroluminescence of ZnO-based semiconductor heterostructures

    SciTech Connect (OSTI)

    Novodvorskii, O A; Lotin, A A; Panchenko, Vladislav Ya; Parshina, L S; Khaidukov, E V; Zuev, D A; Khramova, O D [Institute on Laser and Information Technologies, Russian Academy of Sciences, Shatura, Moscow Region (Russian Federation)

    2011-01-31T23:59:59.000Z

    Using pulsed laser deposition, we have grown n-ZnO/p-GaN, n-ZnO/i-ZnO/p-GaN and n-ZnO/n-Mg{sub 0.2}Zn{sub 0.8}O/i-Cd{sub 0.2}Zn{sub 0.8}O/p-GaN light-emitting diode (LED) heterostructures with peak emission wavelengths of 495, 382 and 465 nm and threshold current densities (used in electroluminescence measurements) of 1.35, 2, and 0.48 A cm{sup -2}, respectively. Because of the spatial carrier confinement, the n-ZnO/n-Mg{sub 0.2}Zn{sub 0.8}O/i-Cd{sub 0.2}Zn{sub 0.8}O/p-GaN double heterostructure LED offers a higher electroluminescence intensity and lower electroluminescence threshold in comparison with the n-ZnO/p-GaN and n-ZnO/i-ZnO/p-GaN LEDs. (lasers)

  12. al pb zn: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    payload. The planar shield was designed to veto background countsproduced by local gamma-ray production in passive material and neutron interactions in the detector. The CdZnTe...

  13. RG1:aased on receipt but intended for use

    E-Print Network [OSTI]

    RG1:aased on receipt but intended for use March 14, 1928 Science Service Feature P W H Y and portable, is much b e t t e r known t o t h e average citizen., In t h i s instrument a thin-walled metal t s reserved by Science Service, Inc.) SCIENCE SERVICE, 21st mci B sts., .Washington, D. ~ C.. #12;

  14. Holography as a highly efficient RG flow : Part 1

    E-Print Network [OSTI]

    Behr, Nicolas; Mukhopadhyay, Ayan

    2015-01-01T23:59:59.000Z

    We investigate how the holographic correspondence can be reconstructed as a special RG flow in a strongly interacting large $N$ field theory. We firstly define a "highly efficient RG flow" as one in which the cut-off in momentum space can be adjusted as a functional of the elementary fields, and of the external sources and of the background metric in order to be compatible with the following requirement: the Ward identities for single-trace operators involving conservation of energy, momentum and global charges must preserve the same form at every scale. In order to absorb the contributions of the multi-trace operators to these effective Ward identities, the external sources and the background metric need to be redefined at each scale, and thus they become dynamical as in the dual gravity equations. We give a schematic construction of such highly efficient RG flows using appropriate collective variables, leaving a more explicit construction in certain limits to the second part of this work. We find that all h...

  15. SCHOOL OF DENTAL HYGIENE Program Requirements Campus: UMICH RG = Requirement Group

    E-Print Network [OSTI]

    Shyy, Wei

    SCHOOL OF DENTAL HYGIENE Program Requirements Campus: UMICH RG = Requirement Group Career: UDH RQ = Requirement Program: 00005 LN = Line RG 4337 SCHOOL OF DENTAL HYGIENE REQUIREMENTS Effective FA04/1510 (09 Optional Pass/Fail (make no exceptions here) RQ 4003 Courses Transferred to the School of Dental Hygiene

  16. ZnO/ZnS(O,OH)/Cu(In,Ga)Se2/Mo SOLAR CELL WITH 18.6% EFFICIENCY M.A. Contreras, 2

    E-Print Network [OSTI]

    Sites, James R.

    of the deposition rate control. Figure 1. Total-area current-voltage data for MgF2/ZnO/ZnS(O,OH)/CIGS/Mo solar cellZnO/ZnS(O,OH)/Cu(In,Ga)Se2/Mo SOLAR CELL WITH 18.6% EFFICIENCY 1 M.A. Contreras, 2 T. Nakada, 2 M of 18.6% for Cu(In,Ga)Se2 solar cells that incorporate a ZnS(O,OH) buffer layer as an alternative to Cd

  17. Intermediate scalings in holographic RG flows and conductivities

    E-Print Network [OSTI]

    Jyotirmoy Bhattacharya; Sera Cremonini; Blaise Goutéraux

    2015-02-04T23:59:59.000Z

    We construct numerically finite density domain-wall solutions which interpolate between two $AdS_4$ fixed points and exhibit an intermediate regime of hyperscaling violation, with or without Lifshitz scaling. Such RG flows can be realized in gravitational models containing a dilatonic scalar and a massive vector field with appropriate choices of the scalar potential and couplings. The infrared $AdS_4$ fixed point describes a new ground state for strongly coupled quantum systems realizing such scalings, thus avoiding the well-known extensive zero temperature entropy associated with $AdS_2 \\times \\mathbb{R}^2$. We also examine the zero temperature behavior of the optical conductivity in these backgrounds and identify two scaling regimes before the UV CFT scaling is reached. The scaling of the conductivity is controlled by the emergent IR conformal symmetry at very low frequencies, and by the intermediate scaling regime at higher frequencies.

  18. High Efficiency Single Crystal CdTe Solar Cells: November 19, 2009 - January 31, 2011

    SciTech Connect (OSTI)

    Carmody, M.; Gilmore, A.

    2011-05-01T23:59:59.000Z

    The goal of the program was to develop single crystal CdTe-based top cells grown on Si solar cells as a platform for the subsequent manufacture of high efficiency tandem cells for CPV applications. The keys to both the single junction and the tandem junction cell architectures are the ability to grow high quality single-crystal CdTe and CdZnTe layers on p-type Si substrates, to dope the CdTe and CdZnTe controllably, both n and p-type, and to make low resistance ohmic front and back contacts. EPIR demonstrated the consistent MBE growth of CdTe/Si and CdZnTe/Si having high crystalline quality despite very large lattice mismatches; epitaxial CdTe/Si and CdZnTe/Si consistently showed state-of-the-art electron mobilities and good hole mobilities; bulk minority carrier recombination lifetimes of unintentionally p-doped CdTe and CdZnTe grown by MBE on Si were demonstrated to be consistently of order 100 ns or longer; desired n- and p-doping levels were achieved; solar cell series specific resistances <10 ?-cm2 were achieved; A single-junction solar cell having a state-of-the-art value of Voc and a unverified 16.4% efficiency was fabricated from CdZnTe having a 1.80 eV bandgap, ideal for the top junction in a tandem cell with a Si bottom junction.

  19. Atom-probe tomographic study of interfaces of Cu{sub 2}ZnSnS{sub 4} photovoltaic cells

    SciTech Connect (OSTI)

    Tajima, S., E-mail: e0954@mosk.tytlabs.co.jp; Asahi, R.; Itoh, T.; Hasegawa, M.; Ohishi, K. [Toyota Central R and D Labs., Inc., 41-1 Yokomichi, Nagakute, Aichi 480-1192 (Japan); Isheim, D.; Seidman, D. N. [Northwestern University, Evanston, Illinois 60208-3108 (United States)

    2014-09-01T23:59:59.000Z

    The heterophase interfaces between the CdS buffer layer and the Cu{sub 2}ZnSnS{sub 4} (CZTS) absorption layers are one of the main factors affecting photovoltaic performance of CZTS cells. We have studied the compositional distributions at heterophase interfaces in CZTS cells using three-dimensional atom-probe tomography. The results demonstrate: (a) diffusion of Cd into the CZTS layer; (b) segregation of Zn at the CdS/CZTS interface; and (c) a change of oxygen and hydrogen concentrations in the CdS layer depending on the heat treatment. Annealing at 573?K after deposition of CdS improves the photovoltaic properties of CZTS cells probably because of the formation of a heterophase epitaxial junction at the CdS/CZTS interface. Conversely, segregation of Zn at the CdS/CZTS interface after annealing at a higher temperature deteriorates the photovoltaic properties.

  20. Selective Zn2+ sensing using a modified bipyridine complex

    SciTech Connect (OSTI)

    Akula, Mahesh; El-Khoury, Patrick Z.; Nag, Amit; Bhattacharya, Anupam

    2014-06-01T23:59:59.000Z

    A novel fluorescent Zn2+ sensor, 4-(pyridin-2-yl)-3H-pyrrolo[2, 3-c]quinoline (PPQ), has been designed, synthesized and characterized by various spectroscopic and analytical techniques. PPQ exhibits superior detection of Zn2+ in the presence of various cations tested, including Cd2+ and Hg2+, via wavelength shifted fluorescence intensity enhancement. The emission wavelength at 500 nm, ensures probable noninterference from cellular components while performing biological applications.

  1. Comparing SNePS with Topbraid/Pellet SNeRG Technical Note 42

    E-Print Network [OSTI]

    Shapiro, Stuart C.

    Comparing SNePS with Topbraid/Pellet SNeRG Technical Note 42 Michael Kandefer and Stuart C. Shapiro Editing Tool (Top Quadrant Inc. 2007) using the Pellet OWL DL Reasoner (Clark & Parsia, LLC 2007

  2. $Re(A_0)$, $Re(A_2)$ and RG evolution for $N_f=3$

    E-Print Network [OSTI]

    Choi, K; Choi, Keunsu; Lee, Weonjong

    2005-01-01T23:59:59.000Z

    We present results of $Re (A_0)$ and $Re (A_2)$ calculated using HYP staggered fermions on the lattice of $16^3 \\times 64$ at $\\beta=6.0$. These results are obtained using leading order chiral perturbation in quenched QCD. Buras's original RG evolution matrix develops a removable singularity for $N_f=3$. This subtlety is resolved by finding a finite solution to RG equation and the results are presented.

  3. Synthesis of CdSe quantum dots for quantum dot sensitized solar cell

    SciTech Connect (OSTI)

    Singh, Neetu, E-mail: singh.neetu1985@gmail.com; Kapoor, Avinashi [Department of Electronic Science, University of Delhi South Campus, New Delhi-110 021 (India); Kumar, Vinod [Department of Physics, University of the Free State, Bloemfontein, ZA9300 (South Africa); Mehra, R. M. [School of Engineering and Technology, Sharda University, Greater Noida-201 306, U.P. (India)

    2014-04-24T23:59:59.000Z

    CdSe Quantum Dots (QDs) of size 0.85 nm were synthesized using chemical route. ZnO based Quantum Dot Sensitized Solar Cell (QDSSC) was fabricated using CdSe QDs as sensitizer. The Pre-synthesized QDs were found to be successfully adsorbed on front ZnO electrode and had potential to replace organic dyes in Dye Sensitized Solar Cells (DSSCs). The efficiency of QDSSC was obtained to be 2.06 % at AM 1.5.

  4. Polarized Raman scattering of single ZnO nanorod

    SciTech Connect (OSTI)

    Yu, J. L., E-mail: jlyu@semi.ac.cn; Lai, Y. F., E-mail: laiyunfeng@gmail.com; Wang, Y. Z.; Cheng, S. Y. [Institute of Micro/Nano Devices and Solar Cells, School of Physics and Information Engineering, Fuzhou University, Fuzhou (China); Chen, Y. H. [Key Laboratory of Semiconductor Materials Science, Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing 100083 (China)

    2014-01-21T23:59:59.000Z

    Polarized Raman scattering measurement on single wurtzite c-plane (001) ZnO nanorod grown by hydrothermal method has been performed at room temperature. The polarization dependence of the intensity of the Raman scattering for the phonon modes A{sub 1}(TO), E{sub 1}(TO), and E{sub 2}{sup high} in the ZnO nanorod are obtained. The deviations of polarization-dependent Raman spectroscopy from the prediction of Raman selection rules are observed, which can be attributed to the structure defects in the ZnO nanorod as confirmed by the comparison of the transmission electron microscopy, photoluminescence spectra as well as the polarization dependent Raman signal of the annealed and unannealed ZnO nanorod. The Raman tensor elements of A{sub 1}(TO) and E{sub 1}(TO) phonon modes normalized to that of the E{sub 2}{sup high} phonon mode are |a/d|=0.32±0.01,?|b/d|=0.49±0.02, and |c/d|=0.23±0.01 for the unannealed ZnO nanorod, and |a/d|=0.33±0.01,?|b/d|=0.45±0.01, and |c/d|=0.20±0.01 for the annealed ZnO nanorod, which shows strong anisotropy compared to that of bulk ZnO epilayer.

  5. Forestry and Social Research Services e-ma : pau .tabbush@v rg n.net

    E-Print Network [OSTI]

    ng account of cu tura va ues n forest p ann ng Pau Tabbush #12;Cultural `Services'/Benefits/Values · Millennium Ecosystem Assessment (`cultural services') · Indicators for monitoring and appraisal · Economistic@v rg n.net #12;Methods · Literature review · Semi-structured interviews · Case studies ­ Thames Chase

  6. Children's Unit for Treatment and Evaluation Dr. R.G. Romanczyk, Director

    E-Print Network [OSTI]

    Suzuki, Masatsugu

    Children's Unit for Treatment and Evaluation Dr. R.G. Romanczyk, Director P.O. Box 6000 Binghamton are subject to clearance through the State Central Register of Child Abuse / Maltreatment and fingerprint instruction and care to children enrolled in the Children's Unit. 1. implement individualized educational

  7. Dynamics of O,,3 Pj...Rg collisions on ab initio and scattering potentials

    E-Print Network [OSTI]

    Krems, Roman

    ) Department of Chemistry, Physical Chemistry, Go¨teborg University, SE-412 96, Go¨teborg, Sweden A. A. The sensitivity of the dynamical results to the nature of Rg atoms and interaction potentials is analyzed transfer kinetics and spectral properties of gas mixtures, discharges, plasmas, atmospheric

  8. Applied Reactor Physics TA RG E T AU D I E N C E

    E-Print Network [OSTI]

    Meunier, Michel

    Applied Reactor Physics TA RG E T AU D I E N C E Applied Reactor Physics is designed for an audi- ence at the graduate level, without preliminary knowledge of reactor physics. A number of excel- lent courses. Most production codes in reactor physics are accompanied with rather complete theory guides

  9. RG improved Higgs boson production to N$^3$LO in QCD

    E-Print Network [OSTI]

    Ahmed, Taushif; Kumar, M C; Rana, Narayan; Ravindran, V

    2015-01-01T23:59:59.000Z

    The recent result on the third order correction to the Higgs boson production through gluon fusion by Anastasiou et al. [1] not only provides a precise prediction with reduced scale uncertainties for studying the Higgs boson properties but also establishes the reliability of the perturbative QCD. In this letter, we propose a novel approach to further reduce the uncertainty arising from the renormalization scale by systematically resumming the renormalization group (RG) accessible logarithms to all orders in the strong coupling constant. Our numerical study based on this approach, demonstrates a significant improvement over the fixed order predictions.

  10. Stability analysis of the Witten black hole (cigar soliton) under world-sheet RG flow

    E-Print Network [OSTI]

    Carolyn Lambert; Vardarajan Suneeta

    2012-09-01T23:59:59.000Z

    We analyze the stability of the Euclidean Witten black hole (the cigar soliton in mathematics literature) under first-order RG (Ricci) flow of the world-sheet sigma model. This analysis is from the target space point of view. We find that the Witten black hole has no unstable normalizable perturbative modes in a linearized mode analysis in which we consider circularly symmetric perturbations. Finally, we discuss a result from mathematics that implies the existence of a non-normalizable mode of the Witten black hole under which the geometry flows to the sausage solution studied by Fateev, Onofri and Zamolodchikov.

  11. COL Application Content Guide for HTGRs: Revision to RG 1.206, Part 1 - Status Report

    SciTech Connect (OSTI)

    Wayne Moe

    2012-08-01T23:59:59.000Z

    A combined license (COL) application is required by the Nuclear Regulatory Commission (NRC) for all proposed nuclear plants. The information requirements for a COL application are set forth in 10 CFR 52.79, “Contents of Applications; Technical Information in Final Safety Analysis Report.” An applicant for a modular high temperature gas-cooled reactor (HTGR) must develop and submit for NRC review and approval a COL application which conforms to these requirements. The technical information necessary to allow NRC staff to evaluate a COL application and resolve all safety issues related to a proposed nuclear plant is detailed and comprehensive. To this, Regulatory Guide (RG) 1.206, “Combined License Applications for Nuclear Power Plants” (LWR Edition), was developed to assist light water reactor (LWR) applicants in incorporating and effectively formatting required information for COL application review (Ref. 1). However, the guidance prescribed in RG 1.206 presumes a LWR design proposal consistent with the systems and functions associated with large LWR power plants currently operating under NRC license.

  12. Changes in Zn speciation during soil formation from Zn-rich Olivier Jacquat a

    E-Print Network [OSTI]

    -containing calcite (at site Dornach), Zn-containing goethite (Gurnigel) and Zn-containing goethite and sphalerite contained substantial amounts of Zn-containing goethite ($50%) stemming from the parent rock, smaller in recalcitrant extraction steps, confirming that Zn-HIV, Zn-containing kaolinite and Zn-containing goethite

  13. Optical properties of ZnO/ZnS and ZnO/ZnTe heterostructures for photovoltaic applications

    E-Print Network [OSTI]

    Schrier, Joshua; Demchenko, Denis O.; Wang, Lin-Wang; Alivisatos, A. Paul

    2008-01-01T23:59:59.000Z

    ZnTe heterostructures for photovoltaic applications Joshuatoo large for optimal photovoltaic e?ciency. By using band-nanowires can be used as photovoltaic devices with organic

  14. Statistics of Single-Molecule Detection Jo1rg Enderlein,* David L. Robbins, W. Patrick Ambrose, Peter M. Goodwin, and

    E-Print Network [OSTI]

    Enderlein, Jörg

    Statistics of Single-Molecule Detection Jo1rg Enderlein,* David L. Robbins, W. Patrick Ambrose for the calculation of the photon detection statistics in single-molecule detection experiments is presented detection statistics in single- molecule detection experiments in a fluid flow. Using a path integral

  15. Proximity effects in superconducting triplet spin-valve F2/F1/S R.G. Deminov a,n

    E-Print Network [OSTI]

    Fominov, Yakov

    Proximity effects in superconducting triplet spin-valve F2/F1/S R.G. Deminov a,n , L.R. Tagirov a effect Superconducting Ferromagnetic Triplet spin-valve Magnetization Transition temperature Interface of the spin-valve effect mode selection (standard switching effect, the triplet spin-valve effect or reentrant

  16. The adsorption of oxygen at GaN surfaces Tosja K. Zywietz, a) Jo rg Neugebauer, and Matthias Scheffler

    E-Print Network [OSTI]

    The adsorption of oxygen at GaN surfaces Tosja K. Zywietz, a) Jo Ë? rg Neugebauer, and Matthias based on GaN is the controlled doping and the incorporation of impurities like, e.g., oxygen. We have explored the adsorption of oxygen at the wurtzite ~0001! and (0001 â?¢ ) GaN surfaces employing density

  17. Leukocyte surface antigen CD47

    E-Print Network [OSTI]

    Soto Pantoja, David R; Kaur, Sukhbir; Miller, Thomas W; Isenberg, Jeffrey S; Roberts, David D

    2013-01-01T23:59:59.000Z

    endothelial cells cultured from the lungs of CD47-null micechallenge of bacteria to the lungs (Su et al. 2008). Theof TSP1 and CD47 in the lungs and elevated expression of

  18. Phase relations and crystal structures in the system Ce-Ni-Zn at 800 Degree-Sign C

    SciTech Connect (OSTI)

    Malik, Z.; Grytsiv, A. [Institute of Physical Chemistry, University of Vienna, Waehringerstrasse 42, A-1090 Vienna (Austria)] [Institute of Physical Chemistry, University of Vienna, Waehringerstrasse 42, A-1090 Vienna (Austria); Rogl, P., E-mail: peter.franz.rogl@univie.ac.at [Institute of Physical Chemistry, University of Vienna, Waehringerstrasse 42, A-1090 Vienna (Austria); Giester, G. [Institute of Mineralogy and Crystallography, University of Vienna, Althanstrasse 14, A-1090 Vienna (Austria)] [Institute of Mineralogy and Crystallography, University of Vienna, Althanstrasse 14, A-1090 Vienna (Austria)

    2012-10-15T23:59:59.000Z

    Phase relations have been established for the system Ce-Ni-Zn in the isothermal section at 800 Degree-Sign C using electron microprobe analysis and X-ray powder diffraction. Phase equilibria at 800 Degree-Sign C are characterized by a large region for the liquid phase covering most of the Ce-rich part of the diagram, whereas a Zn-rich liquid is confined to a small region near the Zn-corner of the Gibbs triangle. Whereas solubility of Ce in the binary Ni-Zn phases is negligible, mutual solubilities of Ni and Zn at a constant Ce content are large at 800 Degree-Sign C for most Ce-Zn and Ce-Ni compounds. The solid solution Ce(Ni{sub 1-x}Zn{sub x}){sub 5} with the CaCu{sub 5}-type is continuous throughout the entire section and for the full temperature region from 400 to 800 Degree-Sign C. Substitution of Zn by Ni is found to stabilize the structure of CeZn{sub 11} to higher temperatures. At 800 Degree-Sign C Ce(Ni{sub x}Zn{sub 1-x}){sub 11} (0.03{<=}x{<=}0.22) appears as a ternary solution phase. Similarly, a rather extended solution forms for Ce{sub 2}(Ni{sub x}Zn{sub 1-x}){sub 17} (0{<=}x{<=}0.53). Detailed data on atom site occupation and atom parameters were derived from X-ray structure analyses for single crystals of Ce{sub 2+y}(Ni{sub x}Zn{sub 1-x}){sub 17}, y=0.02, x=0.49 (a=0.87541(3), c=1.25410(4) nm; Th{sub 2}Zn{sub 17} type with space group R3{sup Macron }m,R{sub F{sup 2}}=0.018) and Ce(Ni{sub 0.18}Zn{sub 0.82}){sub 11} (a=1.04302(2), c=0.67624(3)nm, BaCd{sub 11} type with space group I4{sub 1}/amd, R{sub F{sup 2}}=0.049). - Graphical abstract: Ce-Ni-Zn isothermal section at 800 Degree-Sign C. Highlights: Black-Right-Pointing-Pointer Phase relations were determined for the system Ce-Ni-Zn in the section at 800 Degree-Sign C. Black-Right-Pointing-Pointer A continuous solid solution Ce(Ni{sub 1-x}Zn{sub x}){sub 5}, 0{<=}x{<=}1, forms between 400 and 800 Degree-Sign C. Black-Right-Pointing-Pointer Zn/Ni substitution stabilizes the ternary phase Ce(Zn{sub 1-x}Ni{sub x}){sub 11}, 0.03{<=}x{<=}0.22, 800 Degree-Sign C. Black-Right-Pointing-Pointer An extended solution forms for Ce{sub 2}(Ni{sub x}Zn{sub 1-x}){sub 17} (0{<=}x{<=}0.53). Black-Right-Pointing-Pointer Crystal data are given: Ce{sub 2+y}(Ni{sub x}Zn{sub 1-x}){sub 17} (Th{sub 2}Zn{sub 17}), Ce(Ni{sub 0.18}Zn{sub 0.82}){sub 11} (BaCd{sub 11}).

  19. SYNTHESIS AND SURFACE CHEMISTRY OF ZN3P2 Gregory M. Kimball, Nathan S. Lewis, Harry A. Atwater

    E-Print Network [OSTI]

    Kimball, Gregory

    alternative to traditional materials (e.g. CIGS, CdTe, a-Si) for thin film photovoltaics. Open circuit voltage in Zn3P2 cells has been limited by Fermi-level pinning due to surfaces states and heterojunction promise for solar energy conversion but has not been investigated as thoroughly as other thin film

  20. DISTORTIONS TO CURRENT-VOLTAGE CURVES OF CIGS CELLS WITH SPUTTERED Zn(O,S) BUFFER LAYERS

    E-Print Network [OSTI]

    Sites, James R.

    alternative to CdS for (CIGS) thin-film solar cells' buffer layer. It has a higher band gap and thus allows to current- voltage (J-V) curves of sputtered-Zn(O,S)/CIGS solar cells. A straightforward photodiode model partner in the CIGS team, and Russell for showing me the solar cells characterization, and John, Jen

  1. Local coordination of Zn in hydroxy-interlayered minerals and implications for Zn retention in soils

    E-Print Network [OSTI]

    -interlayered minerals (HIM) for Zn retention in contaminated soils. Published and newly collected extended XLocal coordination of Zn in hydroxy-interlayered minerals and implications for Zn retention. In a second part, we determined the spe- ciation of Zn in eight contaminated soils (251­1039 mg/kg Zn

  2. Regulatory function of cytomegalovirus-specific CD4{sup +}CD27{sup -}CD28{sup -} T cells

    SciTech Connect (OSTI)

    Tovar-Salazar, Adriana; Patterson-Bartlett, Julie; Jesser, Renee [University of Colorado Denver School of Medicine, Aurora, CO (United States); Weinberg, Adriana, E-mail: Adriana.Weinberg@ucdenver.ed [University of Colorado Denver School of Medicine, Aurora, CO (United States)

    2010-03-15T23:59:59.000Z

    CMV infection is characterized by high of frequencies of CD27{sup -}CD28{sup -} T cells. Here we demonstrate that CMV-specific CD4{sup +}CD27{sup -}CD28{sup -} cells are regulatory T cells (T{sub R}). CD4{sup +}CD27{sup -}CD28{sup -} cells sorted from CMV-stimulated PBMC of CMV-seropositive donors inhibited de novo CMV-specific proliferation of autologous PBMC in a dose-dependent fashion. Compared with the entire CMV-stimulated CD4{sup +} T-cell population, higher proportions of CD4{sup +}CD27{sup -}CD28{sup -} T{sub R} expressed FoxP3, TGFbeta, granzyme B, perforin, GITR and PD-1, lower proportions expressed CD127 and PD1-L and similar proportions expressed CD25, CTLA4, Fas-L and GITR-L. CMV-CD4{sup +}CD27{sup -}CD28{sup -} T{sub R} expanded in response to IL-2, but not to CMV antigenic restimulation. The anti-proliferative effect of CMV-CD4{sup +}CD27{sup -}CD28{sup -} T{sub R} significantly decreased after granzyme B or TGFbeta inhibition. The CMV-CD4{sup +}CD27{sup -}CD28{sup -} T{sub R} of HIV-infected and uninfected donors had similar phenotypes and anti-proliferative potency, but HIV-infected individuals had higher proportions of CMV-CD4{sup +}CD27{sup -}CD28{sup -} T{sub R}. The CMV-CD4{sup +}CD27{sup -}CD28{sup -} T{sub R} may contribute to the downregulation of CMV-specific and nonspecific immune responses of CMV-infected individuals.

  3. Performance and Loss Analyses of High-Efficiency CBD-ZnS/Cu(In1-xGax)Se2 Thin-Film Solar Cells

    E-Print Network [OSTI]

    Sites, James R.

    1 Performance and Loss Analyses of High-Efficiency CBD-ZnS/Cu(In1-xGax)Se2 Thin-Film Solar Cells, Setagaya-ku, Tokyo 157-8572, Japan (Received ) KEYWORDS: ZnS buffer, Cu(In,Ga)Se2, thin-film solar cells alternative to CdS in polycrystalline thin-film Cu(In1-xGax)Se2 (CIGS) solar cells. Cells with efficiency

  4. Fluorescence relaxation dynamics of CdSe and CdSe/CdS core/shell quantum dots

    SciTech Connect (OSTI)

    Kaur, Gurvir; Kaur, Harmandeep [Centre of Advanced Study in Physics, Department of Physics, Panjab University, Chandigarh-160014 (India); Tripathi, S. K., E-mail: surya@pu.ac.in [Centre of Advanced Study in Physics, Panjab University, Chandigarh- 160014 (India)

    2014-04-24T23:59:59.000Z

    Time-resolved fluorescence spectra for colloidal CdSe and CdSe/CdS core/shell quantum dots have been investigated to know their electron relaxation dynamics at the maximum steady state fluorescence intensity. CdSe core and CdSe/CdS type I core-shell materials with different shell (CdS) thicknesses have been synthesized using mercaptoacetic acid as a capping agent. Steady state absorption and emission studies confirmed successful synthesis of CdSe and CdSe/CdS core-shell quantum dots. The fluorescence shows a tri-exponential decay with lifetimes 57.39, 7.82 and 0.96 ns for CdSe quantum dots. The lifetime of each recombination decreased with growth of CdS shell over the CdSe core, with maximum contribution to fluorescence by the fastest transition.

  5. Influence of CdTe thickness on structural and electrical properties of CdTe/CdS solar cells

    E-Print Network [OSTI]

    Romeo, Alessandro

    Influence of CdTe thickness on structural and electrical properties of CdTe/CdS solar cells A a b s t r a c ta r t i c l e i n f o Available online xxxx Keywords: Solar cells CdCl2 CdTe Thin absorbers Due to its high scalability and low production cost, CdTe solar cells have shown a very strong

  6. Differential toxicity of heterocyclic aromatic amines and their mixture in metabolically competent HepaRG cells

    SciTech Connect (OSTI)

    Dumont, Julie, E-mail: Julie.Dumont@pasteur-lille.f [Inserm U991, Faculte des Sciences Pharmaceutiques et Biologiques, F-35043 Rennes cedex (France); Universite de Rennes 1, Faculte des Sciences Pharmaceutiques et Biologiques, F-35043 Rennes cedex (France); Josse, Rozenn, E-mail: Rozenn.Josse@univ-rennes1.f [Inserm U991, Faculte des Sciences Pharmaceutiques et Biologiques, F-35043 Rennes cedex (France); Universite de Rennes 1, Faculte des Sciences Pharmaceutiques et Biologiques, F-35043 Rennes cedex (France); Lambert, Carine, E-mail: Carine.Lambert45@gmail.co [Inserm U991, Faculte des Sciences Pharmaceutiques et Biologiques, F-35043 Rennes cedex (France); Universite de Rennes 1, Faculte des Sciences Pharmaceutiques et Biologiques, F-35043 Rennes cedex (France); Antherieu, Sebastien, E-mail: Sebastien.Antherieu@univ-rennes1.f [Inserm U991, Faculte des Sciences Pharmaceutiques et Biologiques, F-35043 Rennes cedex (France); Universite de Rennes 1, Faculte des Sciences Pharmaceutiques et Biologiques, F-35043 Rennes cedex (France); Le Hegarat, Ludovic, E-mail: l.lehegarat@afssa.f [Agence Francaise de Securite Sanitaire des Aliments, F-35300 Fougeres (France); Aninat, Caroline, E-mail: Caroline.Aninat@univ-rennes1.f [Inserm U991, Faculte des Sciences Pharmaceutiques et Biologiques, F-35043 Rennes cedex (France); Universite de Rennes 1, Faculte des Sciences Pharmaceutiques et Biologiques, F-35043 Rennes cedex (France); Robin, Marie-Anne, E-mail: Marie-Anne.Robin@inserm.f [Inserm U991, Faculte des Sciences Pharmaceutiques et Biologiques, F-35043 Rennes cedex (France); Universite de Rennes 1, Faculte des Sciences Pharmaceutiques et Biologiques, F-35043 Rennes cedex (France); Guguen-Guillouzo, Christiane, E-mail: Christiane.Guillouzo@univ-rennes1.f [Inserm U991, Faculte des Sciences Pharmaceutiques et Biologiques, F-35043 Rennes cedex (France); Universite de Rennes 1, Faculte des Sciences Pharmaceutiques et Biologiques, F-35043 Rennes cedex (France)

    2010-06-01T23:59:59.000Z

    Human exposure to heterocyclic aromatic amines (HAA) usually occurs through mixtures rather than individual compounds. However, the toxic effects and related mechanisms of co-exposure to HAA in humans remain unknown. We compared the effects of two of the most common HAA, 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) and 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), individually or in combination, in the metabolically competent human hepatoma HepaRG cells. Various endpoints were measured including cytotoxicity, apoptosis, oxidative stress and DNA damage by the comet assay. Moreover, the effects of PhIP and/or MeIQx on mRNA expression and activities of enzymes involved in their activation and detoxification pathways were evaluated. After a 24 h treatment, PhIP and MeIQx, individually and in combination, exerted differential effects on apoptosis, oxidative stress, DNA damage and cytochrome P450 (CYP) activities. Only PhIP induced DNA damage. It was also a stronger inducer of CYP1A1 and CYP1B1 expression and activity than MeIQx. In contrast, only MeIQx exposure resulted in a significant induction of CYP1A2 activity. The combination of PhIP with MeIQx induced an oxidative stress and showed synergistic effects on apoptosis. However, PhIP-induced genotoxicity was abolished by a co-exposure with MeIQx. Such an inhibitory effect could be explained by a significant decrease in CYP1A2 activity which is responsible for PhIP genotoxicity. Our findings highlight the need to investigate interactions between HAA when assessing risks for human health and provide new insights in the mechanisms of interaction between PhIP and MeIQx.

  7. Toward ZnO Light Emitting Diode

    E-Print Network [OSTI]

    Liu, Jianlin

    2008-01-01T23:59:59.000Z

    applications such as light emitting diodes (LEDs) and laser009 "Toward ZnO Light Emitting Diode" Jianlin Liu July 2008Title: “Toward ZnO Light Emitting Diode” Sponsor: UC Energy

  8. Isoscalar multipole strength in Cd-110 and Cd-116

    E-Print Network [OSTI]

    Lui, YW; Youngblood, David H.; Tokimoto, Y.; Clark, HL; John, B.

    2004-01-01T23:59:59.000Z

    Isoscalar multipole strength in 110Cd and 116Cd Y.-W. Lui, D. H. Youngblood, Y. Tokimoto, H. L. Clark, and B. John* Cyclotron Institute, Texas A&M University, College Station, Texas 77843, USA (Received 6 October 2003; published 24 March 2004... of each multi- pole are shown. The statistical errors are smaller than the data points. LUI, YOUNGBLOOD, TOKIMOTO, CLARK, AND JOHN PHYSICAL REVIEW C 69, 034611 (2004) 034611-2 FIG. 3. Strength distributions obtained for 110Cd are shown...

  9. Structural and magnetic properties of NiZn and Zn ferrite thin films obtained by laser ablation deposition

    E-Print Network [OSTI]

    McHenry, Michael E.

    Structural and magnetic properties of NiZn and Zn ferrite thin films obtained by laser ablation ferrite structures. Our investigations were performed on NiZn and Zn ferrite films deposited on silicon of the blocking temperature in both NiZn and Zn ferrite systems. © 2005 American Institute of Physics. DOI: 10

  10. Structural, optical and magnetic properties of ZnOFe/ZnO multilayers

    SciTech Connect (OSTI)

    Nakayama, H.; Kinoshita, R.; Sakamoto, I. [Hosei University, Koganei, Tokyo 184-8584 (Japan); Yasumoto, M.; Koike, M. [National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki 305-8568 (Japan); Honda, S. [Shimane University, Matsue, Shimane 690-8504 (Japan)

    2013-12-04T23:59:59.000Z

    ZnOFe/ZnO multilayers (MLs) with the constant composition and the different thickness in ZnOFe layers have been prepared by helicon plasma sputtering. The XRD patterns of ZnOFe/ZnO MLs before annealing showed only ZnO diffraction peaks while one after annealing indicated the phases of ZnO and ZnFe{sub 2}O{sub 4}. The magnetization curves of ZnOFe/ZnO MLs before and after annealing showed ferromagnetic behavior. The origin of ferromagnetism in ZnOFe/ZnO MLs before annealing is considered to be due to the formation of defects/vacancies resulting from the substitution of Fe{sup 3+} ions for Zn{sub 2+} ions in ZnOFe layers irrespective of the mixed Fe valence states seen in XANES spectra. The ferromagnetic behavior after annealing is due to the formation of ZnFe{sub 2}O{sub 4}, which was confirmed by XRD, XPS, RBS measurements.

  11. ZnO PN Junctions for Highly-Efficient, Low-Cost Light Emitting Diodes

    SciTech Connect (OSTI)

    David P. Norton; Stephen Pearton; Fan Ren

    2007-09-30T23:59:59.000Z

    By 2015, the US Department of Energy has set as a goal the development of advanced solid state lighting technologies that are more energy efficient, longer lasting, and more cost-effective than current technology. One approach that is most attractive is to utilize light-emitting diode technologies. Although III-V compound semiconductors have been the primary focus in pursuing this objective, ZnO-based materials present some distinct advantages that could yield success in meeting this objective. As with the nitrides, ZnO is a direct bandgap semiconductor whose gap energy (3.2 eV) can be tuned from 3.0 to 4 eV with substitution of Mg for higher bandgap, Cd for lower bandgap. ZnO has an exciton binding energy of 60 meV, which is larger than that for the nitrides, indicating that it should be a superior light emitting semiconductor. Furthermore, ZnO thin films can be deposited at temperatures on the order of 400-600 C, which is significantly lower than that for the nitrides and should lead to lower manufacturing costs. It has also been demonstrated that functional ZnO electronic devices can be fabricated on inexpensive substrates, such as glass. Therefore, for the large-area photonic application of solid state lighting, ZnO holds unique potential. A significant impediment to exploiting ZnO in light-emitting applications has been the absence of effective p-type carrier doping. However, the recent realization of acceptor-doped ZnO material overcomes this impediment, opening the door to ZnO light emitting diode development In this project, the synthesis and properties of ZnO-based pn junctions for light emitting diodes was investigated. The focus was on three issues most pertinent to realizing a ZnO-based solid state lighting technology, namely (1) achieving high p-type carrier concentrations in epitaxial and polycrystalline films, (2) realizing band edge emission from pn homojunctions, and (3) investigating pn heterojunction constructs that should yield efficient light emission. The project engaged established expertise at the University of Florida in ZnO film growth (D. Norton), device fabrication (F. Ren) and wide bandgap photonics (S. Pearton). It addressed p-type doping and junction formation in (Zn,Mg)O alloy thin films. The project employed pulsed laser deposition for film growth. The p-type dopant of interest was primarily phosphorus, given the recent results in our laboratory and elsewhere that this anions can yield p-type ZnO-based materials. The role of Zn interstitials, oxygen vacancies, and/or hydrogen complexes in forming compensating shallow donor levels imposes the need to simultaneously consider the role of in situ and post-growth processing conditions. Temperature-dependent Hall, Seebeck, C-V, and resistivity measurements was used to determine conduction mechanisms, carrier type, and doping. Temperature-dependent photoluminescence was used to determine the location of the acceptor level, injection efficiency, and optical properties of the structures. X-ray diffraction will used to characterize film crystallinity. Using these materials, the fabrication and characterization of (Zn,Mg)O pn homojunction and heterojunction devices was pursued. Electrical characterization of the junction capacitance and I-V behavior was used to extract junction profile and minority carrier lifetime. Electroluminescence from biased junctions was the primary property of interest.

  12. NREL study may provide future guidance in improving CdS/CdTe photovoltaic device performance.

    E-Print Network [OSTI]

    NREL study may provide future guidance in improving CdS/CdTe photovoltaic device performance. The majority of minority carrier lifetime (MCL) studies performed on CdS/CdTe photovoltaic (PV) devices have Carrier Lifetime Measurements in Superstrate and Substrate CdTe PV Devices." Proc. 37th IEEE Photovoltaic

  13. Patterned three-color ZnCdSeZnCdMgSe quantum-well structures for integrated full-color and white light emitters

    E-Print Network [OSTI]

    . This result demonstrates the feasibility of fabricating integrated full-color light emitting diode and laser American Institute of Physics. S0003-6951 00 04149-8 Light emitting diodes LEDs and laser diodes LDs having

  14. Atomic layer deposition of Al-incorporated Zn(O,S) thin films with tunable electrical Helen Hejin Park, Ashwin Jayaraman, Rachel Heasley, Chuanxi Yang, Lauren Hartle, Ravin Mankad, Richard

    E-Print Network [OSTI]

    to the conventional toxic CdS buffer material for CIGS and CZTS solar cells, Zn(O,S) is composed of earth (CBO) at the buffer/absorber interface to optimize the solar cell device performance,13 as illustrated absorber materials, such as Cu(In,Ga)(S,Se)2 (CIGS),1,2 Cu2ZnSn(Se,S)4 (CZTS),3­5 and SnS.6­9 Compared

  15. Intermixing at the absorber-buffer layer interface in thin-film solar cells: The electronic effects of point defects in Cu(In,Ga)(Se,S){sub 2} and Cu{sub 2}ZnSn(Se,S){sub 4} devices

    SciTech Connect (OSTI)

    Varley, J. B.; Lordi, V. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    2014-08-14T23:59:59.000Z

    We investigate point defects in the buffer layers CdS and ZnS that may arise from intermixing with Cu(In,Ga)(S,Se){sub 2} (CIGS) or Cu{sub 2}ZnSn(S,Se){sub 4} (CZTS) absorber layers in thin-film photovoltaics. Using hybrid functional calculations, we characterize the electrical and optical behavior of Cu, In, Ga, Se, Sn, Zn, Na, and K impurities in the buffer. We find that In and Ga substituted on the cation site act as shallow donors in CdS and tend to enhance the prevailing n-type conductivity at the interface facilitated by Cd incorporation in CIGS, whereas they are deep donors in ZnS and will be less effective dopants. Substitutional In and Ga can favorably form complexes with cation vacancies (A-centers) which may contribute to the “red kink” effect observed in some CIGS-based devices. For CZTS absorbers, we find that Zn and Sn defects substituting on the buffer cation site are electrically inactive in n-type buffers and will not supplement the donor doping at the interface as in CIGS/CdS or ZnS devices. Sn may also preferentially incorporate on the S site as a deep acceptor in n-type ZnS, which suggests possible concerns with absorber-related interfacial compensation in CZTS devices with ZnS-derived buffers. Cu, Na, and K impurities are found to all have the same qualitative behavior, most favorably acting as compensating acceptors when substituting on the cation site. Our results suggest one beneficial role of K and Na incorporation in CIGS or CZTS devices is the partial passivation of vacancy-related centers in CdS and ZnS buffers, rendering them less effective interfacial hole traps and recombination centers.

  16. Development of Substrate Structure CdTe Photovoltaic Devices with Performance Exceeding 10%: Preprint

    SciTech Connect (OSTI)

    Dhere, R. G.; Duenow, J. N.; DeHart, C. M.; Li, J. V.; Kuciauskas, D.; Gessert, T. A.

    2012-08-01T23:59:59.000Z

    Most work on CdTe-based solar cells has focused on devices with a superstrate structure. This focus is due to the early success of the superstrate structure in producing high-efficiency cells, problems of suitable ohmic contacts for lightly doped CdTe, and the simplicity of the structure for manufacturing. The development of the CdCl2 heat treatment boosted CdTe technology and perpetuated the use of the superstrate structure. However, despite the beneficial attributes of the superstrate structure, devices with a substrate structure are attractive both commercially and scientifically. The substrate structure eliminates the need for transparent superstrates and thus allows the use of flexible metal and possibly plastic substrates. From a scientific perspective, it allows better control in forming the junction and direct access to the junction for detailed analysis. Research on such devices has been limited. The efficiency of these devices has been limited to around 8% due to low open-circuit voltage (Voc) and fill factor. In this paper, we present our recent device development efforts at NREL on substrate-structure CdTe devices. We have found that processing parameters required to fabricate high-efficiency substrate CdTe PV devices differ from those necessary for traditional superstrate CdTe devices. We have worked on a variety of contact materials including Cu-doped ZnTe and CuxTe. We will present a comparative analysis of the performance of these contacts. In addition, we have studied the influence of fabrication parameters on junction properties. We will present an overview of our development work, which has led to CdTe devices with Voc values of more than 860 mV and NREL-confirmed efficiencies approaching 11%.

  17. Generation of tunable mid-IR radiation by second harmonic in a CdGeAs{sub 2} crystal

    SciTech Connect (OSTI)

    Das, S [Laser Laboratory, Department of Physics, Burdwan University, Burdwan (India)

    2012-03-31T23:59:59.000Z

    Tunable mid-IR radiation is obtained during second harmonic generation of tunable CO{sub 2}-laser radiation using a CdGeAs{sub 2} crystal. Its angular tuning characteristics at the CO{sub 2}- laser wavelength, angular acceptance angle and spectral acceptance are measured. For second harmonic generation at 10.6 {mu}m, the conversion efficiency in the CdGeAs{sub 2} crystal is 90 times higher than that in the ZnGeP{sub 2} crystal.

  18. A CD19/Fc fusion protein for detection of anti-CD19 chimeric antigen receptors.

    E-Print Network [OSTI]

    De Oliveira, Satiro N; Wang, Jiexin; Ryan, Christine; Morrison, Sherie L; Kohn, Donald B; Hollis, Roger P

    2013-01-01T23:59:59.000Z

    Oliveira et al. : A CD19/Fc fusion protein for detection ofof the CD19-IgG 1 Fc fusion was performed under denatur- ingOpen Access A CD19/Fc fusion protein for detection of anti-

  19. A CD19/Fc fusion protein for detection of anti-CD19 chimeric antigen receptors

    E-Print Network [OSTI]

    De Oliveira, Satiro N; Wang, Jiexin; Ryan, Christine; Morrison, Sherie L; Kohn, Donald B; Hollis, Roger P

    2013-01-01T23:59:59.000Z

    Oliveira et al. : A CD19/Fc fusion protein for detection ofof the CD19-IgG 1 Fc fusion was performed under denatur- ingOpen Access A CD19/Fc fusion protein for detection of anti-

  20. Ultraviolet emission from a multi-layer graphene/MgZnO/ZnO light-emitting diode

    SciTech Connect (OSTI)

    Kang, Jang-Won; Choi, Yong-Seok; Goo Kang, Chang; Hun Lee, Byoung [School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of); Kim, Byeong-Hyeok [Department of Nanobio Materials and Electronics, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of); Tu, C. W. [Department of Electrical and Computer Engineering, University of California, San Diego, La Jolla, California 92093-0407 (United States); Park, Seong-Ju, E-mail: sjpark@gist.ac.kr [School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of); Department of Nanobio Materials and Electronics, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of)

    2014-02-03T23:59:59.000Z

    We report on ultraviolet emission from a multi-layer graphene (MLG)/MgZnO/ZnO light-emitting diodes (LED). The p-type MLG and MgZnO in the MLG/MgZnO/ZnO LED are used as transparent hole injection and electron blocking layers, respectively. The current-voltage characteristics of the MLG/MgZnO/ZnO LED show that current transport is dominated by tunneling processes in the MgZnO barrier layer under forward bias conditions. The holes injected from p-type MLG recombine efficiently with the electrons accumulated in ZnO, and the MLG/MgZnO/ZnO LED shows strong ultraviolet emission from the band edge of ZnO and weak red-orange emission from the deep levels of ZnO.

  1. A CD19/Fc fusion protein for detection of anti-CD19 chimeric antigen receptors.

    E-Print Network [OSTI]

    De Oliveira, Satiro N; Wang, Jiexin; Ryan, Christine; Morrison, Sherie L; Kohn, Donald B; Hollis, Roger P

    2013-01-01T23:59:59.000Z

    blocking experiments were performed using anti-human CD19series of experiments. The exons 2 and 4 of the human CD19

  2. WVU FY 2009Expanding West Virginia's Economy WE s t Vi rg i n i a U n i V E r s i t y

    E-Print Network [OSTI]

    Mohaghegh, Shahab

    WVU FY 2009Expanding West Virginia's Economy WE s t Vi rg i n i a U n i V E r s i t y: amy The opinions herein reflect those of the authors and do not reflect those of the West Virginia University Board Direct expenditures from West Virginia University led to a total economic impact of approximately $4

  3. Evaluation of the Teledyne SIDECAR ASIC at cryogenic temperature using a visible hybrid H2RG focal plane array in 32 channel readout

    E-Print Network [OSTI]

    Liske, Jochen

    Evaluation of the Teledyne SIDECAR ASIC at cryogenic temperature using a visible hybrid H2RG focal, Hilo, HI 96720, USA ABSTRACT Teledyne Imaging Sensors (TIS) has developed a new CMOS device known of FPA drive electronics to operate visible and infrared imaging detectors with a fully digital interface

  4. ZnS/Zn(O,OH)S-based buffer layer deposition for solar cells

    DOE Patents [OSTI]

    Bhattacharya, Raghu N. (Littleton, CO)

    2009-11-03T23:59:59.000Z

    The invention provides CBD ZnS/Zn(O,OH)S and spray deposited ZnS/Zn(O,OH)S buffer layers prepared from a solution of zinc salt, thiourea and ammonium hydroxide dissolved in a non-aqueous/aqueous solvent mixture or in 100% non-aqueous solvent. Non-aqueous solvents useful in the invention include methanol, isopropanol and triethyl-amine. One-step deposition procedures are described for CIS, CIGS and other solar cell devices.

  5. Interaction of CO with Surface PdZn Alloys. | EMSL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    with Surface PdZn Alloys. Interaction of CO with Surface PdZn Alloys. Abstract: The adsorption and bonding configuration of CO on clean and Zn-covered Pd(111) surfaces was studied...

  6. Aggregation, Coarsening, and Phase Transformation in ZnSNanoparticles...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Coarsening, and Phase Transformation in ZnS NanoparticlesStudied by Molecular Dynamics Simulations. Aggregation, Coarsening, and Phase Transformation in ZnS...

  7. Studies on intrinsic defects related to Zn vacancy in ZnO nanoparticles

    SciTech Connect (OSTI)

    Singh, V.P. [School of Materials Science and Technology, Indian Institute of Technology (BHU), Varanasi, 221005 (India)] [School of Materials Science and Technology, Indian Institute of Technology (BHU), Varanasi, 221005 (India); Das, D. [UGC-DAE Consortium for Scientific Research, Kolkata Centre (India)] [UGC-DAE Consortium for Scientific Research, Kolkata Centre (India); Rath, Chandana, E-mail: chandanarath@yahoo.com [School of Materials Science and Technology, Indian Institute of Technology (BHU), Varanasi, 221005 (India)] [School of Materials Science and Technology, Indian Institute of Technology (BHU), Varanasi, 221005 (India)

    2013-02-15T23:59:59.000Z

    Graphical abstract: Display Omitted Highlights: ? Williamson–Hall analysis of ZnO indicates strain in the lattice and size is of 20 nm. ? PL shows a broad emission peak in visible range due to native defects. ? Raman active modes corresponding to P6{sub 3}mc and a few additional modes are observed. ? FTIR detects few local vibrational modes of hydrogen attached to zinc vacancies. ? V{sub Zn}-H and Zn + O divacancies are confirmed by PAS. -- Abstract: ZnO being a well known optoelectronic semiconductor, investigations related to the defects are very promising. In this report, we have attempted to detect the defects in ZnO nanoparticles synthesized by the conventional coprecipitation route using various spectroscopic techniques. The broad emission peak observed in photoluminescence spectrum and the non zero slope in Williamson–Hall analysis indicate the defects induced strain in the ZnO lattice. A few additional modes observed in Raman spectrum could be due to the breakdown of the translation symmetry of the lattice caused by defects and/or impurities. The presence of impurities can be ruled out as XRD pattern shows pure wurtzite structure. The presence of the vibrational band related to the Zn vacancies (V{sub Zn}), unintentional hydrogen dopants and their complex defects confirm the defects in ZnO lattice. Positron life time components ?{sub 1} and ?{sub 2} additionally support V{sub Zn} attached to hydrogen and to a cluster of Zn and O di-vacancies respectively.

  8. Industrial Upscaling of CdTe/CdS Thin Film Solar Cells , A. Bosioa

    E-Print Network [OSTI]

    Romeo, Alessandro

    , these devices are already produced in modules of 60x120 cm2 by two companies, namely Antec Solar in GermanyIndustrial Upscaling of CdTe/CdS Thin Film Solar Cells N. Romeoa , A. Bosioa , A. Romeob , S, ABSTRACT: CdTe/CdS thin film solar cells, since they are made with easily scalable techniques

  9. Charge transport in mixed CdSe and CdTe colloidal nanocrystal films

    E-Print Network [OSTI]

    Bawendi, Moungi G.

    We report the influence of trap states on charge transport through films of mixed CdTe and CdSe nanocrystals (NCs) between lateral electrodes, through layered films of CdTe and CdSe NCs in a layered geometry, and through ...

  10. transporters and Zn2+ homeostasis in neurons

    E-Print Network [OSTI]

    Laskowski, Dustin Thomas Program in Neuroscience, Department of Biological Sciences, Ohio University, Athens, this review presents a working model of neuronal Zn2 + homeostasis and discusses the experimental evidence). Similar symptoms are seen in humans suffering from various causes of Zn2 + deficiency (Prasad, 1997

  11. High Efficiency CdTe/CdS Thin Film Solar Cells Prepared by Treating CdTe Films with a Freon Gas in Substitution of CdCl2

    E-Print Network [OSTI]

    Romeo, Alessandro

    High Efficiency CdTe/CdS Thin Film Solar Cells Prepared by Treating CdTe Films with a Freon Gas process. A further simplification has been done by substituting the CdCl2 step by treating CdTe films to treat CdTe. In this case CdCl2 vapor is obtained by a source facing the CdTe film or conveyed from

  12. Photodeposition of Pt on Colloidal CdS and CdSe/CdS Semiconductor Nanostructures

    SciTech Connect (OSTI)

    Dukovic, Gordana; Merkle, Maxwell G.; Nelson, James H.; Hughes, Steven M.; Alivisatos, A. Paul

    2008-08-06T23:59:59.000Z

    Semiconductor photocatalysis has been identified as a promising avenue for the conversion of solar energy into environmentally friendly fuels, most notably by the production of hydrogen from water.[1-5] Nanometer-scale materials in particular have attracted considerable scientific attention as the building blocks for light-harvesting applications.[6,7] Their desirable attributes include tunability of the optical properties with size, amenability to relatively inexpensive low-temperature processing, and a high degree of synthetic sophistication leading to increasingly complex and multi-functional architectures. For photocatalysis in particular, the high surface-to-volume ratios in nanoscale materials should lead to an increased availability of carriers for redox reactions on the nanoparticle surface. Recombination of photoexcited carriers directly competes with photocatalytic activity.[3] Charge separation is often achieved with multi-component heterostructures. An early example is the case of TiO2 powders functionalized with Pt and RuO2 particles, where photoexcited electrons are transferred to Pt (the reduction site) and holes to RuO2 (the oxidation site).[8] More recently, many colloidally synthesized nanometer-scale metal-semiconductor heterostructures have been reported.[7,9,10] A majority of these structures are made by thermal methods.[7,10] We have chosen to study photochemical formation of metal-semiconductor heterostructures. The detailed understanding of the mechanisms involved in photodeposition of metals on nanometer-scale semiconductors is necessary to enable a high degree of synthetic control. At the same time, because the results of metal deposition can be directly observed by electron microscopy, it can be used to understand how factors such as nanocrystal composition, shape, carrier dynamics, and surface chemistry influence the photochemical properties of semiconductor nanocrystals. In this communication, we report on the photodeposition of Pt on colloidal CdS and CdSe/CdS core/shell nanocrystals. Among the II-VI semiconductors, CdS is of particular interest because it has the correct band alignment for water photolysis[2] and has been demonstrated to be photocatalytically active.[11-16] We have found that the photoexcitation of CdS and CdSe/CdS in the presence of an organometallic Pt precursor leads to deposition of Pt nanoparticles on the semiconductor surface. Stark differences are observed in the Pt nanoparticle location on the two substrates, and the photodeposition can be completely inhibited by the modification of the semiconductor surface. Our results suggest that tuning of the semiconductor band structure, spatial organization and surface chemistry should be crucial in the design of photocatalytic nanostructures.

  13. Reactive ZnO/Ti/ZnO interfaces studied by hard x-ray photoelectron spectroscopy

    SciTech Connect (OSTI)

    Knut, Ronny, E-mail: Ronny.Knut@physics.gu.se; Lindblad, Rebecka; Rensmo, Håkan; Karis, Olof [Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala (Sweden); Grachev, Sergey; Faou, Jean-Yvon; Søndergård, Elin [Unité Mixte CNRS/Sain-Gobain Recherche, 39 Quai Lucien Lefranc, 93303 Aubervilliers (France); Gorgoi, Mihaela [Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Str. 15, D-12489 Berlin (Germany)

    2014-01-28T23:59:59.000Z

    The chemistry and intermixing at buried interfaces in sputter deposited ZnO/Ti/ZnO thin layers were studied by hard x-ray photoelectron spectroscopy. The long mean free path of the photoelectrons allowed for detailed studies of the oxidation state, band bending effects, and intrinsic doping of the buried interfaces. Oxidation of the Ti layer was observed when ZnO was deposited on top. When Ti is deposited onto ZnO, Zn Auger peaks acquire a metallic character indicating a strong reduction of ZnO at the interface. Annealing of the stack at 200?°C results in further reduction of ZnO and oxidation of Ti. Above 300?°C, oxygen transport from the bulk of the ZnO layer takes place, leading to re-oxidation of ZnO at the interface and further oxidation of Ti layer. Heating above 500?°C leads to an intermixing of the layers and the formation of a Zn{sub x}TiO{sub y} compound.

  14. Hybrid Electrochromic Fluorescent Poly(DNTD)/CdSe@ZnS Composite Films

    E-Print Network [OSTI]

    Guo, John Zhanhu

    (ICL), Dan F. Smith Department of Chemical Engineering, Lamar University, Beaumont, Texas 77710, United States Department of Chemistry and Biochemistry, Lamar University, Beaumont, Texas 77710, United States

  15. Temperature Dependence of Single CdSe/ZnS Quantum Dots Luminescence Lifetime

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    , such as quantum dots (QDs), has grown dramatically. These semiconductor QDs bridge the gap between single

  16. Distribution of Cr, Pb, Cd, Zn, Fe and Mn in Lake Victoria sediments, East Africa

    SciTech Connect (OSTI)

    Onyari, J.M.; Wandiga, S.O. (Univ. of Nairobi (Kenya))

    1989-06-01T23:59:59.000Z

    The presence of many metals at trace or ultra-trace levels in the human environment has received increased global attention. Sediments as a sink for pollutants are widely recognized pollution sources and diagenesis and biochemical transformations within the sediment may mobilize pollutants posing a threat to a wider biological community. The natural (background) concentrations of heavy metals in lake sediments can be estimated either by analysis of surface sediments in non-polluted regions or by analysis of core samples antedating modern pollution. The distribution pattern of heavy metals in tropical freshwater systems has been little studied. The authors found increased concentrations of lead and other trace metals in Lake Victoria. Thus this study was initiated in order to further investigate the distribution patterns of lead and other metals in Lake Victoria.

  17. RETENTION OF Cd, Cu, Pb AND Zn BY WOOD ASH, LIME AND FUME DUST

    E-Print Network [OSTI]

    Ma, Lena

    to immobilize metals from wastewater and soils (Viraraghavan and Rao, 1991). Various methods to remediate heavy metal contaminated soils and wastes exist, including thermal, biological, and physical/chemical treatments. However, most current treatment technologies are either too costly or only partially effective

  18. Investigation of polycrystalline thin-film CuInSe{sub 2} solar cells based on ZnSe windows. Annual subcontract report, 15 Febraury 1992--14 February 1993

    SciTech Connect (OSTI)

    Olsen, L C [Washington State Univ. at Tri-Cities, Richland, WA (United States)

    1994-05-01T23:59:59.000Z

    Investigations of ZnSe/CIS solar cells are being carried out in an effort to improve the efficiencies CIS cells and to determine if ZnSe is a viable alternative to CdS as a window material. MOCVD growth of ZnSe is accomplished in a SPIRE 500XT reactor housed in the Electronic Materials Laboratory at WSU Tri-Cities by reacting a zinc adduct with H{sub 2}Se. Conductive n-type ZnSe is grown by using iodine as a dopant. Ethyliodide was mixed with helium and installed on one of the gas lines to the system. ZnSe films have been grown on CIS substrates at 200{degrees}C to 250{degrees}C. ZnO is also being deposited by MOCVD by reacting tetrahydrofuran (THF) with a zinc adduct. ZnSe/CIS heterojunctions have been studied by growing n-ZnSe films onto 2 cm x 2 cm CIS substrates diced from materials supplied by Siemens and then depositing an array of aluminum circular areas 2.8.mm in diameter on top of the ZnSe to serve as contacts. Al films are deposited with a thickness of 80 to l00 {angstrom}so that light can pass through the film, thus allowing the illuminated characteristics of the ZnSe/CIS junction to be tested. Accounting for the 20 to 25 % transmittance through the Al film into the ZnSe/CIS structure, current devices have estimated, active-area AM1.5 efficiencies of 14 %. Open circuit voltages > 500 mV are often attained.

  19. GaN/ZnO and AlGaN/ZnO heterostructure LEDs: growth, fabrication, optical and electrical characterization

    E-Print Network [OSTI]

    Wetzel, Christian M.

    GaN/ZnO and AlGaN/ZnO heterostructure LEDs: growth, fabrication, optical and electrical 12180-3590, U.S.A. ABSTRACT The wide bandgap polar semiconductors GaN and ZnO and their related alloys fields, and surface terminations. With a small lattice mismatch of ~1.8 % between GaN and Zn

  20. Appearance of infused zinc ( sup 70 Zn) and oral zinc ( sup 68 Zn) in breast milk

    SciTech Connect (OSTI)

    Moser-Veillon, P.B.; Patterson, K.Y.; Mangels, A.R.; Wallace, G.F.; Veillon, C. (Univ. of Maryland, College Park (United States) Dept. of Agriculture, Beltsville, MD (United States) Perkin-Elmer Corp., Rockville, MD (United States))

    1991-03-15T23:59:59.000Z

    The purpose of this study was to monitor the appearance of a simultaneous intravenous (IV) dose and oral dose of stable isotopes, {sup 70}Zn and {sup 68}Zn, respectively, in breast milk. Three lactating subjects, 2-3 months postpartum were fed a controlled diet which contained an average of 7.8 mg Zn/day. Subjects collected milk samples at the beginning of each feeding for a 24 hour period on the fifth day of the controlled diet. On day 7 of the controlled diet, a 160 ug IV dose of {sup 70}Zn as zinc chloride in saline was infused into each subject. The subjects also received 2 mg of {sup 68 }Zn as zinc chloride in 50 ml of orange juice. Following the stable isotope doses, subjects collected milk samples at the beginning of each feeding for 48 hours, weighing their infants before and after each feeding. The amount of natural Zn, {sup 70}Zn and {sup 68}Zn tracers in the milk was measured by isotope dilution mass spectrometry. The cumulative {sup 70}Zn excretion into breast milk over 48 hours was approximately 1% of the infused dose and the cumulative {sup 68}Zn excretion was smaller still. Thus, only a small fraction of a physiological IV or oral dose of zinc comes out in the milk. The small fraction of {sup 70}Zn and {sup 68}Zn appearing in the milk suggests that circulating zinc and dietary zinc are not rapidly or directly incorporated into breast milk in appreciable amounts.

  1. RG flows from $(1,0)$ 6D SCFTs to $N=1$ SCFTs in four and three dimensions

    E-Print Network [OSTI]

    Karndumri, Parinya

    2015-01-01T23:59:59.000Z

    We study $AdS_5\\times \\Sigma_2$ and $AdS_4\\times \\Sigma_3$ solutions of $N=2$, $SO(4)$ gauged supergravity in seven dimensions with $\\Sigma_{2,3}$ being $S^{2,3}$ or $H^{2,3}$. The $SO(4)$ gauged supergravity is obtained from coupling three vector multiplets to the pure $N=2$, $SU(2)$ gauged supergravity. With a topological mass term for the 3-form field, the $SO(4)\\sim SU(2)\\times SU(2)$ gauged supergravity admits two supersymmetric $AdS_7$ critical points, with $SO(4)$ and $SO(3)$ symmetries, provided that the two gauge couplings for the two $SU(2)$'s are different. These solutions correspond to $N=(1,0)$ superconformal field theories (SCFTs) in six dimensions. In the case of $\\Sigma_2$, we find a class of $AdS_5\\times S^2$ and $AdS_5\\times H^2$ solutions preserving eight supercharges and $SO(2)\\times SO(2)$ or $SO(2)$ symmetries. These should correspond to some $N=1$ four-dimensional SCFTs. We also give RG flow solutions from the $N=(1,0)$ SCFT in six dimensions to these four-dimensional fixed points inclu...

  2. An electrostatic nanogenerator based on ZnO/ZnS core/shell electrets with stabilized quasi-permanent charge

    SciTech Connect (OSTI)

    Wang, Chao; Cai, Liang; Feng, Yajuan; Chen, Lin; Yan, Wensheng, E-mail: ywsh2000@ustc.edu.cn, E-mail: zhsun@ustc.edu.cn; Liu, Qinghua; Yao, Tao; Hu, Fengchun; Pan, Zhiyun; Sun, Zhihu, E-mail: ywsh2000@ustc.edu.cn, E-mail: zhsun@ustc.edu.cn; Wei, Shiqiang [National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230029 (China)

    2014-06-16T23:59:59.000Z

    ZnO-based nanogenerators with excellent performance and convenient functionalization are particularly desirable for self-powered technology, which is however difficult to achieve simultaneously in traditional piezoelectric ZnO nanogenerators. Here, we report a design of electrostatic ZnO nanogenerator by virtue of a type-II ZnO/ZnS core/shell nanostructure electrets, which can turn acoustic waves into electric power with an energy conversion efficiency of 2.2%. The ZnO/ZnS core/shell electrets are charged by ultraviolet irradiation with a long-term stability of the electrostatic charges under ambient condition. The electronic and atomic structure evolution in the charged ZnO/ZnS core/shell electrets are also discussed by detailed experimental and theoretical investigations. This design opens up an alternative path for fabricating robust ZnO-based nanogenerator for future nanotechnology application.

  3. CD

    U.S. Energy Information Administration (EIA) Indexed Site

    to which the building belonged. For instance, a library is an as sembly building, but a library on a university campus may have been reported instead as an education building...

  4. CD

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisiting the TWPSuccess Stories Siteandscience, and8 FY0LinkA Look at theCCICD .... --

  5. Recycling of CdTe photovoltaic waste

    DOE Patents [OSTI]

    Goozner, Robert E. (Charlotte, NC); Long, Mark O. (Charlotte, NC); Drinkard, Jr., William F. (Charlotte, NC)

    1999-01-01T23:59:59.000Z

    A method for extracting and reclaiming metals from scrap CdTe photovoltaic cells and manufacturing waste by leaching the waste with a leaching solution comprising nitric acid and water, skimming any plastic material from the top of the leaching solution, separating the glass substrate from the liquid leachate and electrolyzing the leachate to separate Cd from Te, wherein the Te is deposits onto a cathode while the Cd remains in solution.

  6. Crystal structure and magnetic properties and Zn substitution effects on the spin-chain compound Sr{sub 3}Co{sub 2}O{sub 6}

    SciTech Connect (OSTI)

    Wang, Xia [Superconducting Properties Unit, National Institute for Materials Science, 1-1 Namiki, Tsukuba Ibaraki 305-0044 (Japan); Department of Chemistry, Graduate School of Science, Hokkaido University, Sapporo, Hokkaido 060-0810 (Japan); Guo, Yanfeng, E-mail: Yangfeng.Guo@physics.ox.ac.uk [Superconducting Properties Unit, National Institute for Materials Science, 1-1 Namiki, Tsukuba Ibaraki 305-0044 (Japan); Sun, Ying [International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science, 1-1 Namiki, Tsukuba Ibaraki 305-0044 (Japan); Tsujimoto, Yoshihiro [Materials Processing Unit, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba Ibaraki 305-0047 (Japan); Matsushita, Yoshitaka [Materials Analysis Station, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba Ibaraki 305-0047 (Japan); Yamaura, Kazunari, E-mail: yamaura.kazunari@nims.go.jp [Superconducting Properties Unit, National Institute for Materials Science, 1-1 Namiki, Tsukuba Ibaraki 305-0044 (Japan); Department of Chemistry, Graduate School of Science, Hokkaido University, Sapporo, Hokkaido 060-0810 (Japan)

    2013-08-15T23:59:59.000Z

    The effects of substituting Co on the spin-chain compound Sr{sub 3}Co{sub 2}O{sub 6} with Zn were investigated by synchrotron X-ray diffraction, magnetic susceptibility, isothermal magnetization, and specific heat measurements. To the best of our knowledge, this is the first report to describe the successful substitution of Co in Sr{sub 3}Co{sub 2}O{sub 6} with Zn. The substitution was carried out by a method involving high pressures and temperatures to obtain Sr{sub 3}CoZnO{sub 6}, which crystalized into a K{sub 4}CdCl{sub 6}-derived rhombohedral structure with a space group of R-3c, similar to the host compound. With the Zn substitution, the Ising-type magnetic anisotropy of the host compound remarkably reduced; the newly formed Sr{sub 3}CoZnO{sub 6} became magnetically isotropic with Heisenberg-type characteristics. This could probably be ascribed to the establishment of a different interaction pathway, –Co{sup 4+}(S=1/2)–O–Zn{sup 2+}(S=0)–O–Co{sup 4+}(S=1/2)–. Details of the magnetic properties of Zn substituted Sr{sub 3}Co{sub 2}O{sub 6} were reported. - Graphical abstract: Crystal structure of the spin-chain compound Sr{sub 3}CoZnO{sub 6} synthesized at 6 GPa. Zn atoms preferably occupy the trigonal prism sites rather than the octahedral sites. As a result, the compound is much magnetically isotropic. Highlights: • Effects of substituting Co with Zn on spin-chain magnetism of Sr{sub 3}Co{sub 2}O{sub 6} were studied. • High-pressure synthesis resulted in a solid solution of Sr{sub 3}CoZnO{sub 6}. • Sr{sub 3}CoZnO{sub 6} showed more isotropic magnetism than the host Sr{sub 3}Co{sub 2}O{sub 6}.

  7. CuIn1-xGaxS2 thin film solar cells with ZnxCd1-xS as heterojunction partner Bhaskar Kumar

    E-Print Network [OSTI]

    Sites, James R.

    80523 ABSTRACT Copper indium gallium sulfide, CuIn1-xGaxS2 (CIGS2) solar cells prepared with chemicalCuIn1-xGaxS2 thin film solar cells with ZnxCd1-xS as heterojunction partner Bhaskar Kumar 1 , Parag/heterojunction partner/ ZnO/Cr/Ag contact fingers solar cells of area ~0.44 cm 2 were fabricated at FSEC

  8. 1. INTRODUCTION CdTe/CdS solar cells are among the most promising

    E-Print Network [OSTI]

    Romeo, Alessandro

    efficiency photovoltaic mod- ules. Solar cells with efficiencies of 10 to 16% have been obtained with Cd) is different for different TCOs. This paper describes the effect of CdCl2 treatment on the recrystallization of CdTe, grown on different sub- strates and its influence on the photovoltaic properties of the solar

  9. Novel Stabilization Mechanism on Polar Surfaces: ZnO(0001)-Zn Olga Dulub,1

    E-Print Network [OSTI]

    Diebold, Ulrike

    ¨r Materialphysik and Centre for Computational Materials Science, Universita¨t Wien, A-1090 Wien, Austria (Received identification of the stabilization mechanisms of polar ZnO surfaces and the resulting surface properties would will cancel the polarity. If the Zn-terminated surface is less positive and the O-terminated surface layer

  10. Advanced Combustion Modeling with STAR-CD using Transient Flemelet...

    Broader source: Energy.gov (indexed) [DOE]

    cd-adapco.com Advanced Combustion Modeling with STAR-CD using Transient Flamelet Models: TIF and TFPV Harry Lehtiniemi, Yongzhe Zhang, and Rajesh Rawat CD-adapco Fabian Mauss...

  11. High Efficiency Thin Film CdTe and a-Si Based Solar Cells: Annual Technical Report, 4 March 1999 - 3 March 2000

    SciTech Connect (OSTI)

    Compaan, A. D.; Deng, X.; Bohn, R. G. (The University of Toledo)

    2001-08-29T23:59:59.000Z

    This report describes the research on high-efficiency CdTe-based thin-film solar cells and on high-efficiency a-Si-based thin-film solar cells. Implemented a diode-array spectrograph system and used optical emission spectroscopy to help optimize the reactive sputtering of N-doped ZnTe for CdTe back-contact structures. Identified the photoluminescence signatures of various defect states in CdTe related to Cd vacancies, CuCd acceptors, Cu-VCd complexes, and donor-acceptor pairs, and related these states to instabilities in the hole concentration at room temperature. Showed that Cu is an important non-radiative center in CdS, reducing the PL efficiency. Studied band tailing in CdS weakly alloyed with CdTe and CdTe weakly alloyed with CdS. Fabricated superstrate ITO/CdS/CdTe cells on Mo substrates with efficiencies above 7.5%. Collaborated in studies of EXAFS of Cu in CdTe which indicate a Cu-Te bond length of 2.62 {angstrom} or 6.7% shorter than the CdTe, bond in agreement with calculations of Wei et al. Provided assistance to two groups on laser scribing. Comparatively studied the performance of a-SiGe solar cells and properties of a-SiGe single-layer films deposited using a wide range of H dilution, observed transition from a-SiGe to {mu}c-SiGe at high H dilution and the impact on cell performances. Comparatively studied the performance of a-SiGe solar cells and properties of a-SiGe single-layer films with different Ge contents, suitable for use as component cells of triple-junction devices. Fabricated a-Si-based solar cells on ultra-thin stainless-steel substrate (7.5 micron) and obtained equivalent performance and yield as on the regular SS substrates (127 microns). Comparatively studied the performance of a-Si-based solar cells on SS substrates and on SnO2-coated glass substrates. Studied the performance of p-layers deposited under various deposition conditions for n-i-p type solar cells. Performed an analysis for the component cell current-matching within a triple-junction solar cell.

  12. Unique Challenges Accompany Thick-Shell CdSe/nCdS (n > 10) Nanocrystal Synthesis

    SciTech Connect (OSTI)

    Guo, Y; Marchuk, K; Abraham, R; Sampat, S; Abraham, R.; Fang, N; Malko, AV; Vela, J

    2011-12-23T23:59:59.000Z

    Thick-shell CdSe/nCdS (n {ge} 10) nanocrystals were recently reported that show remarkably suppressed fluorescence intermittency or 'blinking' at the single-particle level as well as slow rates of Auger decay. Unfortunately, whereas CdSe/nCdS nanocrystal synthesis is well-developed up to n {le} 6 CdS monolayers (MLs), reproducible syntheses for n {ge} 10 MLs are less understood. Known procedures sometimes result in homogeneous CdS nucleation instead of heterogeneous, epitaxial CdS nucleation on CdSe, leading to broad and multimodal particle size distributions. Critically, obtained core/shell sizes are often below those desired. This article describes synthetic conditions specific to thick-shell growth (n {ge} 10 and n {ge} 20 MLs) on both small (sub2 nm) and large (>4.5 nm) CdSe cores. We find added secondary amine and low concentration of CdSe cores and molecular precursors give desired core/shell sizes. Amine-induced, partial etching of CdSe cores results in apparent shell-thicknesses slightly beyond those desired, especially for very-thick shells (n {ge} 20 MLs). Thermal ripening and fast precursor injection lead to undesired homogeneous CdS nucleation and incomplete shell growth. Core/shells derived from small CdSe (1.9 nm) have longer PL lifetimes and more pronounced blinking at single-particle level compared with those derived from large CdSe (4.7 nm). We expect our new synthetic approach will lead to a larger throughput of these materials, increasing their availability for fundamental studies and applications.

  13. Preferential induction of the AhR gene battery in HepaRG cells after a single or repeated exposure to heterocyclic aromatic amines

    SciTech Connect (OSTI)

    Dumont, Julie, E-mail: Julie.Dumont@pasteur-lille.fr; Josse, Rozenn, E-mail: Rozenn.Josse@univ-rennes1.fr; Lambert, Carine, E-mail: Carine.Lambert45@gmail.com; Antherieu, Sebastien, E-mail: Sebastien.Antherieu@univ-rennes1.fr; Laurent, Veronique, E-mail: Veronique.Laurent@univ-rennes1.fr; Loyer, Pascal, E-mail: Pascal.Loyer@univ-rennes1.fr; Robin, Marie-Anne, E-mail: Marie-Anne.Robin@inserm.fr; Guillouzo, Andre, E-mail: Andre.Guillouzo@univ-rennes1.f

    2010-11-15T23:59:59.000Z

    2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) and 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) are two of the most common heterocyclic aromatic amines (HAA) produced during cooking of meat, fish and poultry. Both HAA produce different tumor profiles in rodents and are suspected to be carcinogenic in humans. In order to better understand the molecular basis of HAA toxicity, we have analyzed gene expression profiles in the metabolically competent human HepaRG cells using pangenomic oligonucleotide microarrays, after either a single (24-h) or a repeated (28-day) exposure to 10 {mu}M PhIP or MeIQx. The most responsive genes to both HAA were downstream targets of the arylhydrocarbon receptor (AhR): CYP1A1 and CYP1A2 after both time points and CYP1B1 and ALDH3A1 after 28 days. Accordingly, CYP1A1/1A2 induction in HAA-treated HepaRG cells was prevented by chemical inhibition or small interference RNA-mediated down-regulation of the AhR. Consistently, HAA induced activity of the CYP1A1 promoter, which contains a consensus AhR-related xenobiotic-responsive element (XRE). In addition, several other genes exhibited both time-dependent and compound-specific expression changes with, however, a smaller magnitude than previously reported for the prototypical AhR target genes. These changes concerned genes mainly related to cell growth and proliferation, apoptosis, and cancer. In conclusion, these results identify the AhR gene battery as the preferential target of PhIP and MeIQx in HepaRG cells and further support the hypothesis that intake of HAA in diet might increase human cancer risk.

  14. Cyclotron production of {sup 61}Cu using natural Zn and enriched {sup 64}Zn targets

    SciTech Connect (OSTI)

    Asad, A. H.; Smith, S. V.; Chan, S.; Jeffery, C. M.; Morandeau, L.; Price, R. I. [RAPID PET Labs, Medical Technology and Physics, Sir Charles Gairdner Hospital, Perth, Australia, Imaging and Applied Physics, Curtin University, Perth, Australia, and Center of Excellence in Anti-matter Matter Studies, Australian National University, Can (Australia); Brookhaven National Laboratory, Upton, NY (United States) and Center of Excellence in Anti-matter Matter Studies, Australian National University, Canberra (Australia); RAPID PET Labs, Medical Technology and Physics, Sir Charles Gairdner Hospital, Perth (Australia); RAPID PET Labs, Medical Technology and Physics, Sir Charles Gairdner Hospital, Perth (Australia); Center of Excellence in Anti-matter Matter Studies, Australian National University, Canberra, Australia, and Chemistry, University of Western Australia, Pe (Australia); RAPID PET Labs, Medical Technology and Physics, Sir Charles Gairdner Hospital, Perth (Australia); RAPID PET Labs, Medical Technology and Physics, Sir Charles Gairdner Hospital, Perth, Australia and Physics, University of Western Australia, Perth (Australia)

    2012-12-19T23:59:59.000Z

    Copper-61 ({sup 61}Cu) shares with {sup 64}Cu certain advantages for PET diagnostic imaging, but has a shorter half-life (3.4hr vs. 12.7hr) and a greater probability of positron production per disintegration (61% vs. 17.9%). One important application is for in vivo imaging of hypoxic tissue. In this study {sup 61}Cu was produced using the {sup 64}Zn(p,{alpha}){sup 61}Cu reaction on natural Zn or enriched {sup 64}Zn targets. The enriched {sup 64}Zn (99.82%) was electroplated onto high purity gold or silver foils or onto thin Al discs. A typical target bombardment used 30{mu}A; at 11.7, 14.5 or 17.6MeV over 30-60min. The {sup 61}Cu (radiochemical purity of >95%) was separated using a combination of cation and anion exchange columns. The {sup 64}Zn target material was recovered after each run, for re-use. In a direct comparison with enriched {sup 64}Zn-target results, {sup 61}Cu production using the cheaper {sup nat}Zn target proved to be an effective alternative.

  15. Charge-carrier transport and recombination in heteroepitaxial CdTe

    SciTech Connect (OSTI)

    Kuciauskas, Darius, E-mail: Darius.Kuciauskas@nrel.gov; Farrell, Stuart; Dippo, Pat; Moseley, John; Moutinho, Helio; Li, Jian V.; Allende Motz, A. M.; Kanevce, Ana; Zaunbrecher, Katherine; Gessert, Timothy A.; Levi, Dean H.; Metzger, Wyatt K. [National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, Colorado 80401-3305 (United States); Colegrove, Eric; Sivananthan, S. [Microphysics Laboratory, Physics Department, University of Illinois at Chicago, Chicago, Illinois 60612 (United States)

    2014-09-28T23:59:59.000Z

    We analyze charge-carrier dynamics using time-resolved spectroscopy and varying epitaxial CdTe thickness in undoped heteroepitaxial CdTe/ZnTe/Si. By employing one-photon and nonlinear two-photon excitation, we assess surface, interface, and bulk recombination. Two-photon excitation with a focused laser beam enables characterization of recombination velocity at the buried epilayer/substrate interface, 17.5??m from the sample surface. Measurements with a focused two-photon excitation beam also indicate a fast diffusion component, from which we estimate an electron mobility of 650?cm{sup 2} (Vs){sup ?1} and diffusion coefficient D of 17?cm{sup 2}?s{sup ?1}. We find limiting recombination at the epitaxial film surface (surface recombination velocity S{sub surface}?=?(2.8?±?0.3)?×?10{sup 5?}cm?s{sup ?1}) and at the heteroepitaxial interface (interface recombination velocity S{sub interface}?=?(4.8?±?0.5)?×?10{sup 5?}cm?s{sup ?1}). The results demonstrate that reducing surface and interface recombination velocity is critical for photovoltaic solar cells and electronic devices that employ epitaxial CdTe.

  16. DOI : 10. 1051/jp4 :20030389 Zn speciation in

    E-Print Network [OSTI]

    smelter in Northem France ( [Zn] = 6600 and as a 40 cm thick layer on a agricultural soil in 1997. zen

  17. Formation of Zn-rich phyllosilicate, Zn-layered double hydroxide and hydrozincite in contaminated calcareous soils

    E-Print Network [OSTI]

    Jacquat, Olivier

    2009-01-01T23:59:59.000Z

    Zn/Al hydrotalcite in smelter-impacted soils from northernQuantitative Zn speciation in smelter-contaminated soils byand bioavailability of zinc in a smelter contaminated soil.

  18. Recycling of CdTe photovoltaic waste

    DOE Patents [OSTI]

    Goozner, R.E.; Long, M.O.; Drinkard, W.F. Jr.

    1999-04-27T23:59:59.000Z

    A method for extracting and reclaiming metals from scrap CdTe photovoltaic cells and manufacturing waste by leaching the metals in dilute nitric acid, leaching the waste with a leaching solution comprising nitric acid and water, skimming any plastic material from the top of the leaching solution, separating the glass substrate from the liquid leachate, adding a calcium containing base to the leachate to precipitate Cd and Te, separating the precipitated Cd and Te from the leachate, and recovering the calcium-containing base. 3 figs.

  19. Recycling of CdTe photovoltaic waste

    DOE Patents [OSTI]

    Goozner, Robert E. (Charlotte, NC); Long, Mark O. (Charlotte, NC); Drinkard, Jr., William F. (Charlotte, NC)

    1999-04-27T23:59:59.000Z

    A method for extracting and reclaiming metals from scrap CdTe photovoltaic cells and manufacturing waste by leaching the metals in dilute nitric acid, leaching the waste with a leaching solution comprising nitric acid and water, skimming any plastic material from the top of the leaching solution, separating the glass substrate from the liquid leachate, adding a calcium containing base to the leachate to precipitate Cd and Te, separating the precipitated Cd and Te from the leachate, and recovering the calcium-containing base.

  20. Study of stability of ZnO nanoparticles and growth mechanisms of colloidal ZnO nanorods 

    E-Print Network [OSTI]

    Lee, Kwang Jik

    2006-10-30T23:59:59.000Z

    After hydrolyzing zinc acetate in methanol solution, spherical ZnO nanoparticles in the size range from about 2.5 to 5 nm were synthesized by maintaining a ZnO concentration of 0.02M. Compared to ZnO nanoparticles prepared ...

  1. Green emission in carbon doped ZnO films

    SciTech Connect (OSTI)

    Tseng, L. T.; Yi, J. B., E-mail: jiabao.yi@unsw.edu.au; Zhang, X. Y.; Xing, G. Z.; Luo, X.; Li, S. [School of Materials Science and Engineering, University of New South Wales, Kensington, NSW, 2052 (Australia); Fan, H. M. [School of Chemical Engineering, Northwest University, Xi'an 710069 (China); Herng, T. S.; Ding, J. [Department of Materials Science and Engineering, National University of Singapore, 119260 (Singapore); Ionescu, M. [Australian Nuclear Science and Technology Organization, (ANSTO), New Illawarra Road, Lucas Heights, NSW 2234 (Australia)

    2014-06-15T23:59:59.000Z

    The emission behavior of C-doped ZnO films, which were prepared by implantation of carbon into ZnO films, is investigated. Orange/red emission is observed for the films with the thickness of 60–100 nm. However, the film with thickness of 200 nm shows strong green emission. Further investigations by annealing bulk ZnO single crystals under different environments, i.e. Ar, Zn or C vapor, indicated that the complex defects based on Zn interstitials are responsible for the strong green emission. The existence of complex defects was confirmed by electron spin resonance (ESR) and low temperature photoluminescence (PL) measurement.

  2. Twinning effect on photoluminescence spectra of ZnSe nanowires

    SciTech Connect (OSTI)

    Xu, Jing; Wang, Chunrui, E-mail: crwang@dhu.edu.cn; Wu, Binhe; Xu, Xiaofeng [Department of Applied Physics and State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University, 2999 Renmin Rd. North, Songjiang District, Shanghai 201620 (China); Chen, Xiaoshuang [Department of Applied Physics and State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University, 2999 Renmin Rd. North, Songjiang District, Shanghai 201620 (China); National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Science, Shanghai 200083 (China); Oh, Hongseok; Baek, Hyeonjun; Yi, Gyu-Chul [Department of Physics and Astronomy, Seoul National University, 599 Gwanak-ro, Gwanak-gu, Seoul 151-747 (Korea, Republic of)

    2014-11-07T23:59:59.000Z

    Bandgap engineering in a single material along the axial length of nanowires may be realized by arranging periodic twinning, whose twin plane is vertical to the axial length of nanowires. In this paper, we report the effect of twin on photoluminescence of ZnSe nanowires, which refers to the bandgap of it. The exciton-related emission peaks of transverse twinning ZnSe nanowires manifest a 10-meV-blue-shift in comparison with those of longitudinal twinning ZnSe nanowires. The blue-shift is attributed to quantum confinement effect, which is influenced severely by the proportion of wurtzite ZnSe layers in ZnSe nanowires.

  3. Single crystalline multi-petal Cd nanoleaves prepared by thermal reduction of CdO

    SciTech Connect (OSTI)

    Khan, Waheed S. [Research Centre of Materials Science, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081 (China) [Research Centre of Materials Science, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081 (China); National Institute for Biotechnology and Genetic Engineering (NIBGE), P.O. Box No. 577, Jhang Road, Faisalabad (Pakistan); Cao, Chuanbao, E-mail: cbcao@bit.edu.cn [Research Centre of Materials Science, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081 (China)] [Research Centre of Materials Science, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081 (China); Aslam, Imran; Ali, Zulfiqar; Butt, Faheem K.; Mahmood, Tariq; Nabi, Ghulam [Research Centre of Materials Science, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081 (China)] [Research Centre of Materials Science, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081 (China); Ihsan, Ayesha [National Institute for Biotechnology and Genetic Engineering (NIBGE), P.O. Box No. 577, Jhang Road, Faisalabad (Pakistan)] [National Institute for Biotechnology and Genetic Engineering (NIBGE), P.O. Box No. 577, Jhang Road, Faisalabad (Pakistan); Usman, Zahid [Research Centre of Materials Science, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081 (China)] [Research Centre of Materials Science, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081 (China); Rehman, Asma [National Institute for Biotechnology and Genetic Engineering (NIBGE), P.O. Box No. 577, Jhang Road, Faisalabad (Pakistan)] [National Institute for Biotechnology and Genetic Engineering (NIBGE), P.O. Box No. 577, Jhang Road, Faisalabad (Pakistan)

    2013-02-15T23:59:59.000Z

    Highlights: ? Cd nanoleaves are obtained on abraded Cu substrate by thermal reduction of CdO. ? Vapour solid (VS) growth mechanism governs the formation of Cd nanoleaves (CdNLs). ? PL spectrum for CdNLs exhibits a strong ultraviolet (UV) emission band at 353 nm. ? UV band is attributed to interband radiative recombination under Xe illumination. -- Abstract: Multi-petal cadmium metal nanoleaves with 30–40 nm thickness were fabricated on abraded copper substrate by simple thermal reduction of cadmium oxide (CdO) powder at 1050 °C inside horizontal tube furnace (HTF) under nitrogen gas flow. The structural, compositional and morphological characterizations of the as-prepared cadmium nanoleaves (CdNLs) were performed by X-ray diffraction, energy dispersive X-ray spectroscopy, scanning electron microscopy, high resolution transmission electron microscopy and selected area electron diffraction. Non-catalytic vapour–solid (VS) process based growth mechanism governing the formation of CdNLs has been proposed and discussed briefly. Photoluminescence (PL) spectrum for CdNLs measured at room temperature exhibited a single prominent emission band at 353 nm which may either be ascribed to surface oxidation effects or interband radiative recombination under Xe light illumination.

  4. Thermoelectric properties of ZnSb films grown by MOCVD

    SciTech Connect (OSTI)

    Venkatasubramanian, R.; Watko, E.; Colpitts, T.

    1997-07-01T23:59:59.000Z

    The thermoelectric properties of ZnSb films grown by metallorganic chemical vapor deposition (MOCVD) are reported. The growth conditions necessary to obtain stoichiometric ZnSb films and the effects of various growth parameters on the electrical conductivity and Seebeck coefficients of the films are described. The as-grown ZnSb films are p-type. It was observed that the thicker ZnSb films offer improved carrier mobilities and lower free-carrier concentration levels. The Seebeck coefficient of ZnSb films was found to rise rapidly at approximately 160 C. The thicker films, due to the lower doping levels, indicate higher Seebeck coefficients between 25 to 200 C. A short annealing of the ZnSb film at temperatures of {approximately}200 C results in reduced free-carrier level. Thermal conductivity measurements of ZnSb films using the 3-{omega} method are also presented.

  5. Defect induced ferromagnetism in undoped ZnO nanoparticles

    SciTech Connect (OSTI)

    Rainey, K.; Chess, J.; Eixenberger, J.; Tenne, D. A.; Hanna, C. B.; Punnoose, A., E-mail: apunnoos@boisestate.edu [Department of Physics, Boise State University, Boise, Idaho 83725 (United States)

    2014-05-07T23:59:59.000Z

    Undoped ZnO nanoparticles (NPs) with size ?12?nm were produced using forced hydrolysis methods using diethylene glycol (DEG) [called ZnO-I] or denatured ethanol [called ZnO-II] as the reaction solvent; both using Zn acetate dehydrate as precursor. Both samples showed weak ferromagnetic behavior at 300?K with saturation magnetization M{sub s}?=?0.077 ± 0.002 memu/g and 0.088 ± 0.013 memu/g for ZnO-I and ZnO-II samples, respectively. Fourier transform infrared (FTIR) spectra showed that ZnO-I nanocrystals had DEG fragments linked to their surface. Photoluminescence (PL) data showed a broad emission near 500?nm for ZnO-II which is absent in the ZnO-I samples, presumably due to the blocking of surface traps by the capping molecules. Intentional oxygen vacancies created in the ZnO-I NPs by annealing at 450?°C in flowing Ar gas gradually increased M{sub s} up to 90?min and x-ray photoelectron spectra (XPS) suggested that oxygen vacancies may have a key role in the observed changes in M{sub s}. Finally, PL spectra of ZnO showed the appearance of a blue/violet emission, attributed to Zn interstitials, whose intensity changes with annealing time, similar to the trend seen for M{sub s}. The observed variation in the magnetization of ZnO NP with increasing Ar annealing time seems to depend on the changes in the number of Zn interstitials and oxygen vacancies.

  6. Semitransparent ultrathin CdTe solar cells Semitransparent ultrathin CdTe solar cells and durabilityand durability

    E-Print Network [OSTI]

    Rollins, Andrew M.

    Semitransparent ultrathin CdTe solar cells Semitransparent ultrathin CdTe solar cells lines · Thinfilm CIGS--not available in transparent form · Dye sensitized solar thin films· Dye.E. McCandless, W.A. Buchanan. "High throughput processing of CdTe/CdS solar cells with thin absorber

  7. CdTe/CdS solar cells on flexible substrates Xavier Mathew a,*, J. Pantoja Enriquez a

    E-Print Network [OSTI]

    Romeo, Alessandro

    CdTe/CdS solar cells on flexible substrates Xavier Mathew a,*, J. Pantoja Enriquez a , Alessandro Romeo b,c Ayodhya N. Tiwari b,d a Centro de Investigacion en Energia-UNAM, 62580, Temixco, Morelos of CdTe/CdS solar cells on flexible substrates is reviewed in this article. Photovoltaic structures

  8. One-volt p-InP/n-CdSe regenerative photoelectrochemical cell

    SciTech Connect (OSTI)

    Ang, P.G.P.; Sammells, A.F.

    1983-08-01T23:59:59.000Z

    Features and performance of a two-photoelectrode regenerative photoelectrochemical (PEC) cell that yielded a combined photovoltage of more than one volt are reported. The photoanode was n-CdSe, the photocathode was p-InP, and the electrolyte was aqueous sulfide/polysulfide. Details of the fabrication process are provided, including formation of an ohmic contact by sputter deposited gold and then electroplating the photocathode with Zn, followed by a final sputtered gold layer. Tests under 100 mW/sq cm illumination of the unoptimized regenerative cell produced an open circuit voltage of 1.15 V, a short circuit current of 24 mA/sq cm, a fill factor of 0.40, and an overall efficiency of 5.5 percent.

  9. Development and characterization of PCDTBT:CdSe QDs hybrid solar cell

    SciTech Connect (OSTI)

    Dixit, Shiv Kumar, E-mail: shivkumardixit.7@gmail.com; Bhatnagar, Chhavi, E-mail: shivkumardixit.7@gmail.com; Kumari, Anita, E-mail: shivkumardixit.7@gmail.com; Madhwal, Devinder, E-mail: shivkumardixit.7@gmail.com; Bhatnagar, P. K., E-mail: shivkumardixit.7@gmail.com; Mathur, P. C., E-mail: shivkumardixit.7@gmail.com [Department of Electronic Science, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021 (India)

    2014-10-15T23:59:59.000Z

    Solar cell consisting of low band gap polymer poly[N-900-hepta-decanyl-2,7-carbazole-alt-5,5-(40,70-di-2-thienyl-20,10, 30-benzothiadiazole)] (PCDTBT) as donor and cadmium selenide/zinc sulphide (CdSe/ZnS) core shell quantum dots (QDs) as an acceptor has been developed. The absorption measurements show that the absorption coefficient increases in bulk heterojunction (BHJ) structure covering broad absorption spectrum (200nm–700nm). Also, the photoluminescence (PL) of the PCDTBT:QDs film is found to decrease by an order of magnitude showing a significant transfer of electrons to the QDs. With this approach and under broadband white light with an irradiance of 8.19 mW/cm{sup 2}, we have been able to achieve a power conversion efficiency (PCE) of 3.1 % with fill factor 0.42 for our typical solar cell.

  10. Search for 2{\\beta} decay of 116Cd with the help of enriched 116CdWO4 crystal scintillators

    E-Print Network [OSTI]

    Poda, D V; Belli, P; Bernabei, R; Cappella, F; Caracciolo, V; Castellano, S; Chernyak, D M; Cerulli, R; Danevich, F A; d'Angelo, S; Incicchitti, A; Kobychev, V V; Konovalov, S I; Laubenstein, M; Podviyanuk, R B; Polischuk, O G; Shlegel, V N; Tretyak, V I; Umatov, V I; Vasiliev, Ya V

    2014-01-01T23:59:59.000Z

    Cadmium tungstate crystal scintillators enriched in $^{116}$Cd to 82% ($^{116}$CdWO$_4$, total mass of $\\approx$1.2 kg) are used to search for 2$\\beta$ decay of $^{116}$Cd deep underground at the Gran Sasso National Laboratory of the INFN (Italy). The radioactive contamination of the $^{116}$CdWO$_4$ crystals has been studied carefully to reconstruct the background of the detector. The measured half-life of $^{116}$Cd relatively to 2$\

  11. Mechanisms of Cellular Avidity Regulation in CD2CD58-Mediated T Cell Adhesion

    E-Print Network [OSTI]

    Cairo, Christopher W.

    Mechanisms of Cellular Avidity Regulation in CDCD58-Mediated T Cell Adhesion De-Min Zhu, Massachusetts 02115, § Skirball Institute of Biomolecular Medicine and the Department of Pathology, NYU School Roxbury, Massachusetts 02132, and **Hematology Division, Brigham and Women's Hospital, Boston

  12. Current Transients in CdS/CdTe Solar Cells Alan Fahrenbruch

    E-Print Network [OSTI]

    Sites, James R.

    a red (630 nm) LED with an output equivalent to 1 sun for light data. Red (630 nm) and blue (470 nmCurrent Transients in CdS/CdTe Solar Cells Alan Fahrenbruch Colorado State University Department is completely reversible, with a decay to the DS state. The current/time data were taken using an HP 7090A A

  13. Data used in comparisons among SAAPs, wt-DARs, and rg-DARs SAAPs from UniProt are listed in saap_maf.list. For each SAAP, the file provides the UniProt

    E-Print Network [OSTI]

    Zhang, Jianzhi

    Data used in comparisons among SAAPs, wt-DARs, and rg-DARs SAAPs from UniProt are listed in saap 1. All DARs are listed in dar.list. For wt-DARs, the file wt-DAR.ali includes alignments of human protein sequences, structures, and orthologs from species where the wt-DARs appear as wild- types

  14. Spin noise spectroscopy of ZnO

    SciTech Connect (OSTI)

    Horn, H.; Berski, F.; Hübner, J.; Oestreich, M. [Institute for Solid State Physics, Leibniz Universität Hannover, Appelstr. 2, 30167 Hannover (Germany); Balocchi, A.; Marie, X. [INSA-CNRS-UPS, LPCNO, Université de Toulouse, 135 Av. de Rangueil, 31077 Toulouse (France); Mansur-Al-Suleiman, M.; Bakin, A.; Waag, A. [Institute of Semiconductor Technology, Technische Universität Braunschweig, Hans-Sommer-Straße 66, 38106 Braunschweig (Germany)

    2013-12-04T23:59:59.000Z

    We investigate the thermal equilibrium dynamics of electron spins bound to donors in nanoporous ZnO by optical spin noise spectroscopy. The spin noise spectra reveal two noise contributions: A weak spin noise signal from undisturbed localized donor electrons with a dephasing time of 24 ns due to hyperfine interaction and a strong spin noise signal with a spin dephasing time of 5 ns which we attribute to localized donor electrons which interact with lattice defects.

  15. Kinetics of Cd Release from Some Contaminated Calcareous Soils

    SciTech Connect (OSTI)

    Sajadi Tabar, S.; Jalali, M., E-mail: jalali@basu.ac.ir [Bu-Ali Sina University, Department of Soil Science, College of Agriculture (Iran, Islamic Republic of)

    2013-03-15T23:59:59.000Z

    Contamination of soils with heavy metals may pose long-term risk to groundwater quality leading to health implications. Bioavailability of heavy metals, like cadmium (Cd) is strongly affected by sorption and desorption processes. The release of heavy metals from contaminated soils is a major contamination risks to natural waters. The release of Cd from contaminated soils is strongly influenced by its mobility and bioavailability. In this study, the kinetics of Cd desorption from ten samples of contaminated calcareous soils, with widely varying physicochemical properties, were studied using 0.01 M EDTA extraction. The median percentage of Cd released was about 27.7% of the total extractable Cd in the soils. The release of Cd was characterized by an initial fast release rate (of labile fractions) followed by a slower release rate (of less labile fractions) and a model of two first-order reactions adequately describes the observed release of Cd from the studied soil samples. There was positive correlation between the amount of Cd released at first phase of release and Cd in exchangeable fraction, indicating that this fraction of Cd is the main fraction controlling the Cd in the kinetic experiments. There was strongly negative correlation between the amount of Cd released at first and second phases of release and residual fraction, suggesting that this fraction did not contribute in Cd release in the kinetic experiments. The results can be used to provide information for evaluation of Cd potential toxicity and ecological risk from contaminated calcareous soils.

  16. Compared Raman study of the phase transitions in K2ZnCl4 and Rb2ZnCl4, Rb2ZnBr4, K2SeO4

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    787 Compared Raman study of the phase transitions in K2ZnCl4 and Rb2ZnCl4, Rb2ZnBr4, K2SeO4 M to the incommensurate phase is discussed for the four compounds K2SeO4, K2ZnCl4, Rb2ZnCl4 and Rb2ZnBr4 on the basis measurements on K2ZnC'4 known to exhibit successive phase transitions similar to those of K2SeO4

  17. Controllable Template Synthesis of Superconducting Zn Nanowires with

    E-Print Network [OSTI]

    June 9, 2005 ABSTRACT A systematic study was conducted on the fabrication, structural characterization by electrodepositing Zn into commercially available polycarbonate (PC) or anodic aluminum oxide (AAO) membranes

  18. Built-in electric field in ZnO based semipolar quantum wells grown on (1012) ZnO substrates

    SciTech Connect (OSTI)

    Chauveau, J.-M.; Xia, Y.; Roland, B.; Vinter, B. [Centre de Recherche sur l'Hétéro-Epitaxie et ses Applications, Centre National de la Recherche Scientifique (CRHEA-CNRS), Rue B. Gregory, F-06560 Valbonne Sophia Antipolis (France) [Centre de Recherche sur l'Hétéro-Epitaxie et ses Applications, Centre National de la Recherche Scientifique (CRHEA-CNRS), Rue B. Gregory, F-06560 Valbonne Sophia Antipolis (France); University of Nice Sophia Antipolis, Parc Valrose, F-06102 Nice Cedex 2 (France); Ben Taazaet-Belgacem, I.; Teisseire, M.; Nemoz, M.; Brault, J.; Damilano, B.; Leroux, M. [Centre de Recherche sur l'Hétéro-Epitaxie et ses Applications, Centre National de la Recherche Scientifique (CRHEA-CNRS), Rue B. Gregory, F-06560 Valbonne Sophia Antipolis (France)] [Centre de Recherche sur l'Hétéro-Epitaxie et ses Applications, Centre National de la Recherche Scientifique (CRHEA-CNRS), Rue B. Gregory, F-06560 Valbonne Sophia Antipolis (France)

    2013-12-23T23:59:59.000Z

    We report on the properties of semipolar (Zn,Mg)O/ZnO quantum wells homoepitaxially grown by molecular beam epitaxy on (1012) R-plane ZnO substrates. We demonstrate that atomically flat interfaces can be achieved with fully relaxed quantum wells because the mismatch between (Zn,Mg)O and ZnO is minimal for this growth orientation. The photoluminescence properties evidence a quantum confined Stark effect with an internal electric field estimated to 430 kV/cm for a 17% Mg content in the barriers. The quantum well emission is strongly polarized along the 1210 direction and a comparison with the semipolar bulk ZnO luminescence polarization points to the effect of the confinement.

  19. Formation of Zn-rich phyllosilicate, Zn-layered double hydroxide and hydrozincite in contaminated calcareous soils

    E-Print Network [OSTI]

    Jacquat, Olivier

    2009-01-01T23:59:59.000Z

    soil thin section and corresponding -XRF maps (black: lowestsection and corresponding - XRF maps for Zn, Ca, Fe and Mn (soil thin section and corresponding -XRF maps (black: lowest

  20. Advanced Combustion Modeling with STAR-CD using Transient Flemelet...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Modeling with STAR-CD using Transient Flemelet Models: TIF and TPV Advanced Combustion Modeling with STAR-CD using Transient Flemelet Models: TIF and TPV Presentation given at the...

  1. ag cd cu: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Kretchmar, R. Matthew 122 p-Doping limit and donor compensation in CdTe polycrystalline thin film solar cells Physics Websites Summary: May 2010 Keywords: CdTe p-Doping Hole...

  2. The reversal of the laser-beam-induced-current contrast with varying illumination density in a Cu{sub 2}ZnSnSe{sub 4} thin-film solar cell

    SciTech Connect (OSTI)

    Chen, Qiong; Zhang, Yong, E-mail: yong.zhang@uncc.edu [Department of Electrical and Computer Engineering, and Energy Production and Infrastructure Center (EPIC), The University of North Carolina at Charlotte, Charlotte, North Carolina 28223 (United States)] [Department of Electrical and Computer Engineering, and Energy Production and Infrastructure Center (EPIC), The University of North Carolina at Charlotte, Charlotte, North Carolina 28223 (United States)

    2013-12-09T23:59:59.000Z

    We apply an array of correlated spatially-resolved techniques, including ?-Raman/photoluminescence/reflectance/laser-beam-induced-current in conjunction with scanning electron microscopy and atomic force microscopy, to study the impact of the microscopic-scale thickness inhomogeneity of CdS layer in a Cu{sub 2}ZnSnSe{sub 4} thin-film solar cell. Thicker CdS regions are found to cause more light reflecting loss thus yield lower external quantum efficiencies and energy conversion efficiencies than the general area. However, these regions show much less efficiency degradation at high illumination intensity, leading to an inversion of laser-beam-induced-current contrast in the area mapping. While improving the CdS layer uniformity can boost the device performance, the finding further points out the possibility of operating thin-film photovoltaic devices based on the similar materials (such as CuInGaSe{sub 2}, CdTe, Cu{sub 2}ZnSn(S,Se){sub 4}) under a substantially higher illumination density for concentrated photovoltaic and photo-detection.

  3. Indentation creep study on ultrafine-grained Zn processed by powder metallurgy

    E-Print Network [OSTI]

    Gubicza, Jenõ

    t Ultrafine-grained Zn (UFG-Zn) with the grain size of about 200 nm was processed by Spark Plasma Sintering

  4. Organic Molecule Functionalized Zn3P2 Nanowire Inorganic-Organic...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Molecule Functionalized Zn3P2 Nanowire Inorganic-Organic Hybrid Thermoelectrics Organic Molecule Functionalized Zn3P2 Nanowire Inorganic-Organic Hybrid Thermoelectrics Demonstrates...

  5. Evidence of significant down-conversion in a Si-based solar cell using CuInS{sub 2}/ZnS core shell quantum dots

    SciTech Connect (OSTI)

    Gardelis, Spiros, E-mail: S.Gardelis@imel.demokritos.gr; Nassiopoulou, Androula G. [NCSR Demokritos INN, Terma Patriarchou Grigoriou, Aghia Paraskevi, 15310 Athens (Greece)

    2014-05-05T23:59:59.000Z

    We report on the increase of up to 37.5% in conversion efficiency of a Si-based solar cell after deposition of light-emitting Cd-free, CuInS{sub 2}/ZnS core shell quantum dots on the active area of the cell due to the combined effect of down-conversion and the anti- reflecting property of the dots. We clearly distinguished the effect of down-conversion from anti-reflection and estimated an enhancement of up to 10.5% in the conversion efficiency due to down-conversion.

  6. Benefits of homoepitaxy on the properties of nonpolar (Zn,Mg)O/ZnO quantum wells on a-plane ZnO substrates

    SciTech Connect (OSTI)

    Chauveau, J.-M.; Vinter, B. [Centre de Recherche sur l'Hetero-Epitaxie et ses Applications (CRHEA), Centre National de la Recherche Scientifique (CNRS), Rue B. Gregory, F-06560 Valbonne Sophia Antipolis (France); University of Nice Sophia Antipolis, Parc Valrose, F-06102 Nice Cedex 2 (France); Teisseire, M.; Kim-Chauveau, H.; Deparis, C.; Morhain, C. [Centre de Recherche sur l'Hetero-Epitaxie et ses Applications (CRHEA), Centre National de la Recherche Scientifique (CNRS), Rue B. Gregory, F-06560 Valbonne Sophia Antipolis (France)

    2010-08-23T23:59:59.000Z

    We report on the properties of nonpolar (Zn,Mg)O/ZnO quantum wells (QW) homoepitaxially grown by molecular beam epitaxy on a-plane ZnO substrates. We demonstrate a drastic improvement of the structural properties. We compare the photoluminescence properties of nonpolar homoepitaxial QWs and nonpolar heteroepitaxial QWs grown on sapphire and show that the reduction in structural defects and the improvement of surface morphology are correlated with a strong enhancement of the photoluminescence properties: reduction in full width at half maximum, strong increase in the luminescence intensities and their thermal stability. The comparison convincingly demonstrates the interest of homoepitaxial nonpolar QWs for bright UV emission applications.

  7. Femtosecond dynamics of Cu,,CD3OD... Jack Barbera

    E-Print Network [OSTI]

    Lineberger, W. Carl

    Femtosecond dynamics of Cu,,CD3OD... Jack Barbera JILA, University of Colorado, Boulder, Colorado online 27 February 2007 We report the femtosecond nuclear dynamics of Cu CD3OD van der Waals clusters, investigated using photodetachment-photoionization spectroscopy. Photodetachment of an electron from Cu- CD3OD

  8. Neutral nitrogen acceptors in ZnO: The {sup 67}Zn hyperfine interactions

    SciTech Connect (OSTI)

    Golden, E. M.; Giles, N. C., E-mail: Nancy.Giles@afit.edu [Department of Engineering Physics, Air Force Institute of Technology, Wright-Patterson Air Force Base, Ohio 45433 (United States); Evans, S. M.; Halliburton, L. E. [Department of Physics, West Virginia University, Morgantown, West Virginia 26506 (United States)

    2014-03-14T23:59:59.000Z

    Electron paramagnetic resonance (EPR) is used to characterize the {sup 67}Zn hyperfine interactions associated with neutral nitrogen acceptors in zinc oxide. Data are obtained from an n-type bulk crystal grown by the seeded chemical vapor transport method. Singly ionized nitrogen acceptors (N{sup ?}) initially present in the crystal are converted to their paramagnetic neutral charge state (N{sup 0}) during exposure at low temperature to 442 or 633?nm laser light. The EPR signals from these N{sup 0} acceptors are best observed near 5?K. Nitrogen substitutes for oxygen ions and has four nearest-neighbor cations. The zinc ion along the [0001] direction is referred to as an axial neighbor and the three equivalent zinc ions in the basal plane are referred to as nonaxial neighbors. For axial neighbors, the {sup 67}Zn hyperfine parameters are A{sub ?}?=?37.0?MHz and A{sub ?}?=?8.4?MHz with the unique direction being [0001]. For nonaxial neighbors, the {sup 67}Zn parameters are A{sub 1}?=?14.5?MHz, A{sub 2}?=?18.3?MHz, and A{sub 3}?=?20.5?MHz with A{sub 3} along a [101{sup ¯}0] direction (i.e., in the basal plane toward the nitrogen) and A{sub 2} along the [0001] direction. These {sup 67}Zn results and the related {sup 14}N hyperfine parameters provide information about the distribution of unpaired spin density at substitutional neutral nitrogen acceptors in ZnO.

  9. 1. INTRODUCTION CdTe/CdS is one of the most promising solar cell for low

    E-Print Network [OSTI]

    Romeo, Alessandro

    1. INTRODUCTION CdTe/CdS is one of the most promising solar cell for low cost and high efficiency conversion of solar energy into electricity. Solar cells with efficiencies of 10 to 16% have been obtained of super- strate solar cells. CdS layers are grown in a high vacuum evaporation chamber at a substrate

  10. SrZn{sub 2}Sn{sub 2} and Ca{sub 2}Zn{sub 3}Sn{sub 6} - two new Ae-Zn-Sn polar intermetallic compounds (Ae: alkaline earth metal)

    SciTech Connect (OSTI)

    Stegmaier, Saskia [Department Chemie, Technische Universitaet Muenchen, Lichtenbergstrasse 4, 85747 Garching (Germany); Faessler, Thomas F., E-mail: Thomas.Faessler@lrz.tum.de [Department Chemie, Technische Universitaet Muenchen, Lichtenbergstrasse 4, 85747 Garching (Germany)

    2012-08-15T23:59:59.000Z

    SrZn{sub 2}Sn{sub 2} and Ca{sub 2}Zn{sub 3}Sn{sub 6}, two closely related new polar intermetallic compounds, were obtained by high temperature reactions of the elements. Their crystal structures were determined with single crystal XRD methods, and their electronic structures were analyzed by means of DFT calculations. The Zn-Sn structure part of SrZn{sub 2}Sn{sub 2} comprises (anti-)PbO-like {l_brace}ZnSn{sub 4/4}{r_brace} and {l_brace}SnZn{sub 4/4}{r_brace} layers. Ca{sub 2}Zn{sub 3}Sn{sub 6} shows similar {l_brace}ZnSn{sub 4/4}{r_brace} layers and {l_brace}Sn{sub 4}Zn{r_brace} slabs constructed of a covalently bonded Sn scaffold capped by Zn atoms. For both phases, the two types of layers are alternatingly stacked and interconnected via Zn-Sn bonds. SrZn{sub 2}Sn{sub 2} adopts the SrPd{sub 2}Bi{sub 2} structure type, and Ca{sub 2}Zn{sub 3}Sn{sub 6} is isotypic to the R{sub 2}Zn{sub 3}Ge{sub 6} compounds (R=La, Ce, Pr, Nd). Band structure calculations indicate that both SrZn{sub 2}Sn{sub 2} and Ca{sub 2}Zn{sub 3}Sn{sub 6} are metallic. Analyses of the chemical bonding with the electron localization function (ELF) show lone pair like basins at Sn atoms and Zn-Sn bonding interactions between the layers for both title phases, and covalent Sn-Sn bonding within the {l_brace}Sn{sub 4}Zn{r_brace} layers of Ca{sub 2}Zn{sub 3}Sn{sub 6}. - Graphical abstract: Crystal structures of the new Ae-Zn-Sn polar intermetallic phases SrZn{sub 2}Sn{sub 2} and Ca{sub 2}Zn{sub 3}Sn{sub 6}. Highlights: Black-Right-Pointing-Pointer New polar intermetallic phases SrZn{sub 2}Sn{sub 2} and Ca{sub 2}Zn{sub 3}Sn{sub 6}. Black-Right-Pointing-Pointer Obtained by high temperature reactions of the elements. Black-Right-Pointing-Pointer Single crystal XRD structure determination and DFT electronic structure calculations. Black-Right-Pointing-Pointer Closely related crystal and electronic structures. Black-Right-Pointing-Pointer Metallic conductivity coexisting with lone pairs and covalent bonding features.

  11. The effect of ZnO surface conditions on the electronic structure of the ZnO/CuPc interface

    SciTech Connect (OSTI)

    Park, Sang Han; Kim, Hyo Jin; Cho, Mann-Ho [Institute of Physics and Applied Physics, Yonsei University, Seoul 120-749 (Korea, Republic of); Yi, Yeonjin [Division of Industrial Metrology, KRISS, Daejeon 305-340 (Korea, Republic of); Cho, Sang Wan [Department of Physics, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215 (United States); Yang, Jaehyun; Kim, Hyoungsub [School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)

    2011-02-21T23:59:59.000Z

    The interfacial electronic structures of zinc oxide (ZnO)/copper-phthalocyanine (CuPc) were investigated by in situ x-ray and ultraviolet photoelectron spectroscopy (UPS) to determine the effects of air contamination on the ZnO substrate. UPS spectra showed that the 0.2 eV of the interface dipole is generated at the interface of the air exposed ZnO/CuPc while the interface of the annealed ZnO/CuPc generated -0.2 eV. In both cases, no band bending was observed. On the other hand, band bending at 0.3 eV and an interface dipole of 0.2 eV were observed at the interface of the sputter cleaned ZnO/CuPc. The energy offset between the conduction band maximum of ZnO and the highest occupied molecular orbital of CuPc was determined to be 0.6-0.7 eV for the contaminated ZnO interface while the offset was 1.0 eV for the cleaned ZnO interface. Contaminating moisture has little effect on the offset while the charge transfer was blocked and the offset was decreased in the presence of hydrocarbons.

  12. ZnO/Cu(InGa)Se.sub.2 solar cells prepared by vapor phase Zn doping

    SciTech Connect (OSTI)

    Ramanathan, Kannan; Hasoon, Falah S.; Asher, Sarah E.; Dolan, James; Keane, James C.

    2007-02-20T23:59:59.000Z

    A process for making a thin film ZnO/Cu(InGa)Se.sub.2 solar cell without depositing a buffer layer and by Zn doping from a vapor phase, comprising: depositing Cu(InGa)Se.sub.2 layer on a metal back contact deposited on a glass substrate; heating the Cu(InGa)Se.sub.2 layer on the metal back contact on the glass substrate to a temperature range between about 100.degree. C. to about 250.degree. C.; subjecting the heated layer of Cu(InGa)Se.sub.2 to an evaporant species from a Zn compound; and sputter depositing ZnO on the Zn compound evaporant species treated layer of Cu(InGa)Se.sub.2.

  13. ZnO/Cu(InGa)Se2 solar cells prepared by vapor phase Zn doping

    DOE Patents [OSTI]

    Ramanathan, Kannan; Hasoon, Falah S.; Asher, Sarah E.; Dolan, James; Keane, James C.

    2007-02-20T23:59:59.000Z

    A process for making a thin film ZnO/Cu(InGa)Se2 solar cell without depositing a buffer layer and by Zn doping from a vapor phase, comprising: depositing Cu(InGa)Se2 layer on a metal back contact deposited on a glass substrate; heating the Cu(InGa)Se2 layer on the metal back contact on the glass substrate to a temperature range between about 100.degree. C. to about 250.degree. C.; subjecting the heated layer of Cu(InGa)Se2 to an evaporant species from a Zn compound; and sputter depositing ZnO on the Zn compound evaporant species treated layer of Cu(InGa)Se2.

  14. Growth and morphology of cadmium chalcogenides: the synthesis of nanorods, tetrapods, and spheres from CdO and Cd(O2CCH3)2

    E-Print Network [OSTI]

    dependent properties that inorganic nanocrystals exhibit make them of great fundamental and technical, and Te) via the pyrolysis of CdO and Cd(O2CCH3)2 precursors, at the specific Cd to E mole ratio of 0, CdSe and CdTe exhibit rod-like and tetrapod-like morphologies of temporally controllable aspect

  15. Double beta decays of {sup 106}Cd

    SciTech Connect (OSTI)

    Suhonen, Jouni [Department of Physics, P.O. Box 35 (YFL), FI-40014 University of Jyvaeskylae (Finland)

    2011-12-16T23:59:59.000Z

    The two-neutrino (2{nu}2{beta}) and neutrinoless (0{nu}2{beta}) double beta decays of {sup 106}Cd are studied for the transitions to the ground state 0{sub gs}{sup +} and 0{sup +} and 2{sup +} excited states in {sup 106}Pd by using realistic many-body wave functions calculated in the framework of the quasiparticle random-phase approximation. Effective, G-matrix-derived nuclear forces are used in realistic single-particle model spaces. All the possible channels, {beta}{sup +}{beta}{sup +}, {beta}{sup +}EC, and ECEC, are discussed for both the 2{nu}2{beta} and 0{nu}2{beta} decays. The associated half-lives are computed and particular attention is devoted to the study of the detectability of the resonant neutrinoless double electron capture (R0{nu}ECEC) process in {sup 106}Cd. The calculations of the present article constitute the thus far most complete and up-to-date investigation of the double-beta-decay properties of {sup 106}Cd.

  16. Air-gap gating of MgZnO/ZnO heterostructures

    SciTech Connect (OSTI)

    Tambo, T.; Falson, J., E-mail: falson@kwsk.t.u-tokyo.ac.jp; Kozuka, Y. [Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), University of Tokyo, Tokyo 113-8656 (Japan); Maryenko, D. [RIKEN Center for Emergent Matter Science (CEMS), Wako 351-0198 (Japan); Tsukazaki, A. [Institute for Materials Research (IMR), Tohoku University, Sendai 980-8577 (Japan); PRESTO, Japan Science and Technology Agency (JST), Tokyo 102-0075 (Japan); Kawasaki, M. [Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), University of Tokyo, Tokyo 113-8656 (Japan); RIKEN Center for Emergent Matter Science (CEMS), Wako 351-0198 (Japan)

    2014-08-28T23:59:59.000Z

    The adaptation of “air-gap” dielectric based field-effect transistor technology to controlling the MgZnO/ZnO heterointerface confined two-dimensional electron system (2DES) is reported. We find it possible to tune the charge density of the 2DES via a gate electrode spatially separated from the heterostructure surface by a distance of 5??m. Under static gating, the observation of the quantum Hall effect suggests that the charge carrier density remains homogeneous, with the 2DES in the 3?mm square sample the sole conductor. The availability of this technology enables the exploration of the charge carrier density degree of freedom in the pristine sample limit.

  17. REGULAR ARTICLE Stability of polar ZnO surfaces studied by pair potential

    E-Print Network [OSTI]

    Li, Weixue

    density method Keju Sun · Hai-Yan Su · Wei-Xue Li Received: 1 September 2013 / Accepted: 16 November 2013. The overestimation of the stability of the ZnO(0001)­Zn terminal originates from more distribution of the transferred temperature sublimation processes indicated a higher sublimation rate of the ZnO(0001)­Zn surface compared

  18. Methotrexate intercalated ZnAl-layered double hydroxide

    SciTech Connect (OSTI)

    Chakraborty, Manjusha; Dasgupta, Sudip; Soundrapandian, Chidambaram [Central Glass and Ceramic Research Institute, CSIR, 196 Raja S.C. Mullick Road, Kolkata 700032 (India); Chakraborty, Jui, E-mail: jui@cgcri.res.in [Central Glass and Ceramic Research Institute, CSIR, 196 Raja S.C. Mullick Road, Kolkata 700032 (India); Ghosh, Swapankumar, E-mail: swapankumar.ghosh2@mail.dcu.ie [National Institute for Interdisciplinary Science and Technology (NIIST), CSIR, Trivandrum 695019 (India); Mitra, Manoj K. [Department of Metallurgical and Materials Engineering, Jadavpur University, Kolkata 700032 (India); Basu, Debabrata [Central Glass and Ceramic Research Institute, CSIR, 196 Raja S.C. Mullick Road, Kolkata 700032 (India)

    2011-09-15T23:59:59.000Z

    The anticancerous drug methotrexate (MTX) has been intercalated into an ZnAl-layered double hydroxide (LDH) using an anion exchange technique to produce LDH-MTX hybrids having particle sizes in the range of 100-300 nm. X-ray diffraction studies revealed increases in the basal spacings of ZnAl-LDH-MTX hybrid on MTX intercalation. This was corroborated by the transmission electron micrographs, which showed an increase in average interlayer spacing from 8.9 A in pristine LDH to 21.3 A in LDH-MTX hybrid. Thermogravimetric analyses showed an increase in the decomposition temperature for the MTX molecule in the LDH-MTX hybrid indicating enhanced thermal stability of the drug molecule in the LDH nanovehicle. The cumulative release profile of MTX from ZnAl-LDH-MTX hybrids in phosphate buffer saline (PBS) at pH 7.4 was successfully sustained for 48 h following Rigter-Peppas model release kinetics via diffusion. - Graphical abstract: ZnAl-layered double hydroxide intercalated with methotrexate ({approx}34% loading) promises the possibility of use of ZnAl-LDH material as drug carrier and in controlled delivery. Highlights: > ZnAl-layered double hydroxide methotrexate nanohybrid has been synthesized. > XRD and TEM studies on nanohybrid revealed successful intercalation of methotrexate. > TG and CHN analyses showed {approx}34 wt% of methotrexate loading into the nanohybrid. > Possibility of use of ZnAl-LDH material as drug carrier and in delivery.

  19. Radioactive contamination of ZnWO4 crystal scintillators

    E-Print Network [OSTI]

    P. Belli; R. Bernabei; F. Cappella; R. Cerulli; F. A. Danevich; A. M. Dubovik; S. d'Angelo; E. N. Galashov; B. V. Grinyov; A. Incicchitti; V. V. Kobychev; M. Laubenstein; L. L. Nagornaya; F. Nozzoli; D. V. Poda; R. B. Podviyanuk; O. G. Polischuk; D. Prosperi; V. N. Shlegel; V. I. Tretyak; I. A. Tupitsyna; Ya. V. Vasiliev; Yu. Ya. Vostretsov

    2010-09-05T23:59:59.000Z

    The radioactive contamination of ZnWO4 crystal scintillators has been measured deep underground at the Gran Sasso National Laboratory (LNGS) of the INFN in Italy with a total exposure 3197 kg x h. Monte Carlo simulation, time-amplitude and pulse-shape analyses of the data have been applied to estimate the radioactive contamination of the ZnWO4 samples. One of the ZnWO4 crystals has also been tested by ultra-low background gamma spectrometry. The radioactive contaminations of the ZnWO4 samples do not exceed 0.002 -- 0.8 mBq/kg (depending on the radionuclide), the total alpha activity is in the range: 0.2 - 2 mBq/kg. Particular radioactivity, beta active 65Zn and alpha active 180W, has been detected. The effect of the re-crystallization on the radiopurity of the ZnWO4 crystal has been studied. The radioactive contamination of samples of the ceramic details of the set-ups used in the crystals growth has been checked by low background gamma spectrometry. A project scheme on further improvement of the radiopurity level of the ZnWO4 crystal scintillators is briefly addressed.

  20. String-Net Models with $Z_N$ Fusion Algebra

    E-Print Network [OSTI]

    Ling-Yan Hung; Yidun Wan

    2012-12-19T23:59:59.000Z

    We study the Levin-Wen string-net model with a $Z_N$ type fusion algebra. Solutions of the local constraints of this model correspond to $Z_N$ gauge theory and double Chern-simons theories with quantum groups. For the first time, we explicitly construct a spin-$(N-1)/2$ model with $Z_N$ gauge symmetry on a triangular lattice as an exact dual model of the string-net model with a $Z_N$ type fusion algebra on a honeycomb lattice. This exact duality exists only when the spins are coupled to a $Z_N$ gauge field living on the links of the triangular lattice. The ungauged $Z_N$ lattice spin models are a class of quantum systems that bear symmetry-protected topological phases that may be classified by the third cohomology group $H^3(Z_N,U(1))$ of $Z_N$. Our results apply also to any case where the fusion algebra is identified with a finite group algebra or a quantusm group algebra.

  1. Effect of implanted species on thermal evolution of ion-induced defects in ZnO

    SciTech Connect (OSTI)

    Azarov, A. Yu.; Rauwel, P.; Kuznetsov, A. Yu.; Svensson, B. G. [Department of Physics, Centre for Materials Science and Nanotechnology, University of Oslo, PO Box 1048 Blindern, N-0316 Oslo (Norway); Hallén, A. [Royal Institute of Technology, KTH-ICT, Electrum 229, SE-164 40, Kista, Stockholm (Sweden); Du, X. L. [Institute of Physics, The Chinese Academy of Sciences, Beijing 100190 (China)

    2014-02-21T23:59:59.000Z

    Implanted atoms can affect the evolution of ion-induced defects in radiation hard materials exhibiting a high dynamic annealing and these processes are poorly understood. Here, we study the thermal evolution of structural defects in wurtzite ZnO samples implanted at room temperature with a wide range of ion species (from {sup 11}B to {sup 209}Bi) to ion doses up to 2?×?10{sup 16}?cm{sup ?2}. The structural disorder was characterized by a combination of Rutherford backscattering spectrometry, nuclear reaction analysis, and transmission electron microscopy, while secondary ion mass spectrometry was used to monitor the behavior of both the implanted elements and residual impurities, such as Li. The results show that the damage formation and its thermal evolution strongly depend on the ion species. In particular, for F implanted samples, a strong out-diffusion of the implanted ions results in an efficient crystal recovery already at 600?°C, while co-implantation with B (via BF{sub 2}) ions suppresses both the F out-diffusion and the lattice recovery at such low temperatures. The damage produced by heavy ions (such as Cd, Au, and Bi) exhibits a two-stage annealing behavior where efficient removal of point defects and small defect clusters occurs at temperatures ?500?°C, while the second stage is characterized by a gradual and partial annealing of extended defects. These defects can persist even after treatment at 900?°C. In contrast, the defects produced by light and medium mass ions (O, B, and Zn) exhibit a more gradual annealing with increasing temperature without distinct stages. In addition, effects of the implanted species may lead to a nontrivial defect evolution during the annealing, with N, Ag, and Er as prime examples. In general, the obtained results are interpreted in terms of formation of different dopant-defect complexes and their thermal stability.

  2. Characterization of cancer stem cell properties of CD24 and CD26-positive human malignant mesothelioma cells

    SciTech Connect (OSTI)

    Yamazaki, Hiroto; Naito, Motohiko; Ghani, Farhana Ishrat [Division of Clinical Immunology, Institute of Medical Science, University of Tokyo, Tokyo (Japan)] [Division of Clinical Immunology, Institute of Medical Science, University of Tokyo, Tokyo (Japan); Dang, Nam H. [Division of Hematology/Oncology, University of Florida Shands Cancer Center, Gainesville, FL 32610 (United States)] [Division of Hematology/Oncology, University of Florida Shands Cancer Center, Gainesville, FL 32610 (United States); Iwata, Satoshi [Division of Clinical Immunology, Institute of Medical Science, University of Tokyo, Tokyo (Japan)] [Division of Clinical Immunology, Institute of Medical Science, University of Tokyo, Tokyo (Japan); Morimoto, Chikao, E-mail: morimoto@ims.u-tokyo.ac.jp [Division of Clinical Immunology, Institute of Medical Science, University of Tokyo, Tokyo (Japan)] [Division of Clinical Immunology, Institute of Medical Science, University of Tokyo, Tokyo (Japan)

    2012-03-16T23:59:59.000Z

    Highlights: Black-Right-Pointing-Pointer We focused on CD24 and CD26 for further analysis of CSC properties in MM. Black-Right-Pointing-Pointer Their expressions were correlated with chemoresistance, cell growth, and invasion. Black-Right-Pointing-Pointer Their expressions were also correlated with several cancer related genes. Black-Right-Pointing-Pointer The expression of each marker was correlated with different CSC property in Meso1. Black-Right-Pointing-Pointer Phosphorylation of ERK by EGF was regulated by expression of CD26, but not CD24. -- Abstract: Malignant mesothelioma (MM) is an asbestos-related malignancy characterized by rapid growth and poor prognosis. In our previous study, we have demonstrated that several cancer stem cell (CSC) markers correlated with CSC properties in MM cells. Among these markers, we focused on two: CD24, the common CSC marker, and CD26, the additional CSC marker. We further analyzed the CSC properties of CD24 and CD26-positve MM cells. We established RNAi-knockdown cells and found that these markers were significantly correlated with chemoresistance, proliferation, and invasion potentials in vitro. Interestingly, while Meso-1 cells expressed both CD24 and CD26, the presence of each of these two markers was correlated with different CSC property. In addition, downstream signaling of these markers was explored by microarray analysis, which revealed that their expressions were correlated with several cancer-related genes. Furthermore, phosphorylation of ERK by EGF stimulation was significantly affected by the expression of CD26, but not CD24. These results suggest that CD24 and CD26 differentially regulate the CSC potentials of MM and could be promising targets for CSC-oriented therapy.

  3. Mixed Zn and O substitution of Co and Mn in ZnO

    E-Print Network [OSTI]

    Pereira, Lino Miguel da Costa; Decoster, Stefan; Correia, João Guilherme; Amorim, Lígia Marina; da Silva, Manuel Ribeiro; Araújo, João Pedro; Vantomme, André

    2011-01-01T23:59:59.000Z

    The physical properties of an impurity atom in a semiconductor are primarily determined by the lattice site it occupies. In general, this occupancy can be correctly predicted based on chemical intuition, but not always. We report on one such exception in the dilute magnetic semiconductors Co- and Mn-doped ZnO, experimentally determining the lattice location of Co and Mn using ??-emission channeling from the decay of radioactive 61Co and 56Mn implanted at the ISOLDE facility at CERN. Surprisingly, in addition to the majority substituting for Zn, we find up to 18% (27%) of the Co (Mn) atoms in O sites, which is virtually unaffected by thermal annealing up to 900 °C. We discuss how this anion site configuration, which had never been considered before for any transition metal in any metal oxide material, may in fact have a low formation energy. This suggests a change in paradigm regarding transition-metal incorporation in ZnO and possibly other oxides and wide-gap semiconductors.

  4. Pulse Electrodeposition of Cu-ZnO and Mn-Cu-ZnO Nanowires

    SciTech Connect (OSTI)

    Gupta, Mayank; Pinisetty, D.; Flake, John C.; Spivey, James J.

    2010-01-01T23:59:59.000Z

    Cu–ZnO and Mn–Cu–ZnO nanowires are attractive catalysts for alcohol synthesis from CO hydrogenation reactions. Nanowire alloys are pulse electrodeposited into track etched polycarbonate membranes using aqueous electrolytes including Mn(NO{sub 3} ){sub 2} , Cu(NO{sub 3} ){sub 2} , Zn(NO{sub 3} ){sub 2} , and NH{sub 4} NO{sub 3} . Pulse waveforms with a cathodic current density of 50.7mAcm{sup ?2} for 50 ms (on-time), with varying off-times (400, 500, and 600 ms), are used to fabricate nanowire arrays (400 nm diameter, 25?m long, and pore density of 1.5×10{sup 8} pores cm{sup ?2} ). Pulse waveforms allow significantly higher copper concentrations and better control of zinc and manganese concentrations within nanowires. X-ray diffraction results show preferential growth in the (111) direction and crystallite size increases with an increase in off-time. Waveforms with longer off-times (500 and 600 ms) resulted in nanowires with relatively higher copper concentrations due to improved copper transport in nanopores. The nanowire surface has no manganese; however, the core shows manganese, which increases with the decrease in off-time. The effect of deposition conditions and electrolyte composition on nanowire properties are explained and discussed.

  5. Modification of solid state CdZnTe (CZT) radiation detectors with high sensitivity or high resolution operation

    DOE Patents [OSTI]

    Washington, II, Aaron L; Duff, Martine C; Teague, Lucile C; Burger, Arnold; Groza, Michael

    2014-11-11T23:59:59.000Z

    An apparatus and process is provided to illustrate the manipulation of the internal electric field of CZT using multiple wavelength light illumination on the crystal surface at RT. The control of the internal electric field is shown through the polarization in the IR transmission image under illumination as a result of the Pockels effect.

  6. Linking heavy metal bioavailability (Cd, Cu, Zn and Pb) in Scots pine needles to soil properties in reclaimed mine areas

    E-Print Network [OSTI]

    Battles, John

    spoil, and hard coal spoil heaps are the consequences of fossil fuels and mineral extraction and are examples of large scale land transformation. Although land area directly affected by mining of minerals, 2012). From an ecological point of view, reclamation is a process of restoring the ecosystem (Hüttl

  7. SIXTH QUARTERLY REPORT OF RESEARCH ON CuxS - (Cd,Zn)S PHOTOVOLTAIC SOLAR ENERGY CONVERTERS

    E-Print Network [OSTI]

    Chin, B.L.

    2011-01-01T23:59:59.000Z

    for use in experimental photovoltaic cells. Hall mobilityvacuum method for photovoltaic cell fabrication" However,

  8. ZnO Nanocoral Structures for Photoelectrochemical Cells

    SciTech Connect (OSTI)

    Ahn, K. S.; Yan, Y.; Shet, S.; Jones, K.; Deutsch, T.; Turner, J.; Al-Jassim, M.

    2008-01-01T23:59:59.000Z

    We report on synthesis of a uniform and large area of a new form of ZnO nanocorals. These nanostructures can provide suitable electrical pathways for efficient carrier collection as well as large surface areas for the photoelectrochemical (PEC) cells. PEC devices made from these ZnO nanocoral structures demonstrate significantly enhanced photoresponse as compared to ZnO compact and nanorod films. Our results suggest that the nanocoral structures could be an excellent choice for nanomaterial-based applications such as dye-sensitized solar cells, electrochromic windows, and batteries.

  9. Minority anion substitution by Ni in ZnO

    E-Print Network [OSTI]

    Pereira, Lino Miguel da Costa; Correia, João Guilherme; Amorim, Lígia Marina; Silva, Daniel José; David-Bosne, Eric; Decoster, Stefan; da Silva, Manuel Ribeiro; Temst, Kristiaan; Vantomme, André

    2013-01-01T23:59:59.000Z

    We report on the lattice location of implanted Ni in ZnO using the $\\beta$? emission channeling technique. In addition to the majority substituting for the cation (Zn), a significant fraction of the Ni atoms occupy anion (O) sites. Since Ni is chemically more similar to Zn than it is to O, the observed O substitution is rather puzzling. We discuss these findings with respect to the general understanding of lattice location of dopants in compound semiconductors. In particular, we discuss potential implications on the magnetic behavior of transition metal doped dilute magnetic semiconductors.

  10. The effects of fabrication temperature on current-voltage characteristics and energy efficiencies of quantum dot sensitized ZnOH-GO hybrid solar cells

    SciTech Connect (OSTI)

    Islam, S. M. Z. [IUSL, Department of Physics, The City College of New York, 160 Convent Ave., New York, New York 10031 (United States); Department of Physics and Engineering Physics, Fordham University, 441 E. Fordham Road, Bronx, New York 10458 (United States); Department of Electrical Engineering, The City College of New York, 160 Convent Ave., New York, New York 10031 (United States); Gayen, Taposh [IUSL, Department of Physics, The City College of New York, 160 Convent Ave., New York, New York 10031 (United States); Department of Physics and Engineering Physics, Fordham University, 441 E. Fordham Road, Bronx, New York 10458 (United States); Tint, Naing; Alfano, Robert, E-mail: ralfano@sci.ccny.cuny.edu [IUSL, Department of Physics, The City College of New York, 160 Convent Ave., New York, New York 10031 (United States); Department of Electrical Engineering, The City College of New York, 160 Convent Ave., New York, New York 10031 (United States); Shi, Lingyan [IUSL, Department of Physics, The City College of New York, 160 Convent Ave., New York, New York 10031 (United States); Department of Biomedical Engineering, The City College of New York, 160 Convent Ave., New York, New York 10031 (United States); Seredych, Mykola; Bandosz, Teresa J. [Department of Chemistry, The City College of New York, 160 Convent Ave., New York, New York 10031 (United States)

    2014-11-07T23:59:59.000Z

    The effects of fabrication temperature are investigated on the performance of CdSe quantum dot (QD)-sensitized hybrid solar cells of the composite material of zinc (hydr)oxide (ZnOH-GO)with 2?wt.?% graphite oxide. The current-voltage (I-V) and photo-current measurements show that higher fabrication temperatures yield greater photovoltaic power conversion efficiencies that essentially indicate more efficient solar cells. Two Photon Fluorescence images show the effects of temperature on the internal morphologies of the solar devices based on such materials. The CdSe-QD sensitized ZnOH-GO hybrid solar cells fabricated at 450?°C showing conversion of ?10.60% under a tungsten lamp (12.1 mW/cm{sup 2}) are reported here, while using potassium iodide as an electrolyte. The output photocurrent, I (?A) with input power, P (mW/cm{sup 2}) is found to be superlinear, showing a relation of I?=?P{sup n}, where n?=?1.4.

  11. Development of CdS/CdTe Tin Film Devices for St. Gobain Coated Glass: Cooperative Research and Development Final Report, CRADA Number CRD-08-317

    SciTech Connect (OSTI)

    Gessert, T.

    2012-04-01T23:59:59.000Z

    Research performed at NREL to produce CdS/CdTe devices on St. Gobain coated-glass material to establish a baseline CdS/CdTe device process and determine baseline device performance parameters on St. Gobain material. Performance of these baseline devices compared to similar devices produced by applying the established baseline CdS/CdTe process on alternative St. Gobain coated-glass materials.

  12. Hot exciton transport in ZnSe quantum wells

    E-Print Network [OSTI]

    Zhao, Hui; Moehl, Sebastian; Wachter, Sven; Kalt, Heinz

    2002-02-01T23:59:59.000Z

    The in-plane transport of excitons in ZnSe quantum wells is investigated directly by microphotoluminescence in combination with a solid immersion lens. Due to the strong Froehlich coupling, the initial kinetic energy of the excitons is well...

  13. The Nature of Zn Precipitates Formed in the Presence of

    E-Print Network [OSTI]

    Sparks, Donald L.

    to the structure of various hydroxide- and carbonate-bearing phases indicates the formation of a Zn-Al layered metal sequestration mechanism in certain soil types is important to assessment of contaminant

  14. Microscopic picture of Co clustering in ZnO

    E-Print Network [OSTI]

    Iusan, Diana

    Density functional theory was applied to study the chemical and magnetic interactions between Co atoms doped in ZnO. It was found that the Co impurities tend to form nanoclusters and the interactions between these atoms ...

  15. CD-2: Orogenic Belt | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:EzfeedflagBiomassSustainable andBucoda,BurkeNebraska: EnergyByronTechnologiesCD-2: Orogenic

  16. cd ordering | netl.doe.gov

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron4 Self-Scrubbing:,, , ., ..., ,+ . :, ,.2 MesabaCarbon CaptureCD-DVD

  17. DIRECT EVIDENCE OF MG-ZN-P ALLOY FORMATION IN MG/ZN3P2 SOLAR CELLS Gregory M. Kimball

    E-Print Network [OSTI]

    Kimball, Gregory

    Te, CIGS, a-Si) for thin film photovoltaics. The record solar energy conversion efficiency for Zn3P2 cellsDIRECT EVIDENCE OF MG-ZN-P ALLOY FORMATION IN MG/ZN3P2 SOLAR CELLS Gregory M. Kimball 1 , Nathan S indicate that high efficiency should be realizable by optimization of Mg treatment in Mg/Zn3P2 solar cells

  18. Electron Transfer Between Colloidal ZnO Nanocrystals

    SciTech Connect (OSTI)

    Hayoun, Rebecca; Whitaker, Kelly M.; Gamelin, Daniel R.; Mayer, James M.

    2011-03-30T23:59:59.000Z

    Colloidal ZnO nanocrystals capped with dodecylamine and dissolved in toluene can be charged photochemically to give stable solutions in which electrons are present in the conduction bands of the nanocrystals. These conduction-band electrons are readily monitored by EPR spectroscopy, with g* values that correlate with the nanocrystal sizes. Mixing a solution of charged small nanocrystals (e{sub CB}{sup -}:ZnO-S) with a solution of uncharged large nanocrystals (ZnO-L) caused changes in the EPR spectrum indicative of quantitative electron transfer from small to large nanocrystals. EPR spectra of the reverse reaction, e{sub CB}{sup -}:ZnO-L + ZnO-S, showed that electrons do not transfer from large to small nanocrystals. Stopped-flow kinetics studies monitoring the change in the UV bandedge absorption showed that reactions of 50 {micro}M nanocrystals were complete within the 5 ms mixing time of the instrument. Similar results were obtained for the reaction of charged nanocrystals with methyl viologen (MV{sup 2+}). These and related results indicate that the electron-transfer reactions of these colloidal nanocrystals are quantitative and very rapid, despite the presence of {approx}1.5 nm long dodecylamine capping ligands. These soluble ZnO nanocrystals are thus well-defined redox reagents suitable for studies of electron transfer involving semiconductor nanostructures.

  19. Radioactive contamination of ZnWO4 crystal scintillators

    E-Print Network [OSTI]

    Belli, P; Cappella, F; Cerulli, R; Danevich, F A; Dubovik, A M; d'Angelo, S; Galashov, E N; Grinyov, B V; Incicchitti, A; Kobychev, V V; Laubenstein, M; Nagornaya, L L; Nozzoli, F; Poda, D V; Podviyanuk, R B; Polischuk, O G; Prosperi, D; Shlegel, V N; Tretyak, V I; Tupitsyna, I A; Vasiliev, Ya V; Vostretsov, Yu Ya

    2010-01-01T23:59:59.000Z

    The radioactive contamination of ZnWO4 crystal scintillators has been measured deep underground at the Gran Sasso National Laboratory (LNGS) of the INFN in Italy with a total exposure 3197 kg x h. Monte Carlo simulation, time-amplitude and pulse-shape analyses of the data have been applied to estimate the radioactive contamination of the ZnWO4 samples. One of the ZnWO4 crystals has also been tested by ultra-low background gamma spectrometry. The radioactive contaminations of the ZnWO4 samples do not exceed 0.002 â?? 0.8 mBq/kg (depending on the radionuclide), the total alpha activity is in the range: 0.2 - 2 mBq/kg. Particular radioactivity, beta active 65Zn and alpha active 180W, has been detected. The effect of the re-crystallization on the radiopurity of the ZnWO4 crystal has been studied. The radioactive contamination of samples of the ceramic details of the set-ups used in the crystals growth has been checked by low background gamma spectrometry. A project scheme on further improvement of the radiopur...

  20. Non-oxidative reactions of propane on Zn/Na-ZSM5 Joseph A. Biscardi and Enrique Iglesia*

    E-Print Network [OSTI]

    Iglesia, Enrique

    Non-oxidative reactions of propane on Zn/Na-ZSM5 Joseph A. Biscardi and Enrique Iglesia* Department rates during propane conversion at 773 K on Zn/Na-ZSM5 are about ten times higher than on Zn/H-ZSM5 catalysts with similar Zn content. The total rate of propane conversion is also higher on Zn/Na-ZSM5

  1. Formation of Zn-rich phyllosilicate, Zn-layered double hydroxide and hydrozincite in contaminated calcareous soils

    E-Print Network [OSTI]

    Jacquat, Olivier

    2009-01-01T23:59:59.000Z

    and chemical extractions. Am. Mineral. 88, 509-526.extraction for speciation of trace- metals in model soil containing natural mineralson these minerals). Prior to extraction, the Zn-phases were

  2. Hard X-ray polarimetry with Caliste, a high performance CdTe based imaging spectrometer

    E-Print Network [OSTI]

    S. Antier; P. Ferrando; O. Limousin; E. Caroli; R. M. Curado da Silva; C. Blondel; R. Chipaux; V. Honkimaki; B. Horeau; P. Laurent; J. M. Maia; A. Meuris; S. Del Sordo; J. B. Stephen

    2015-05-05T23:59:59.000Z

    Since the initial exploration of soft gamma-ray sky in the 60's, high-energy celestial sources have been mainly characterized through imaging, spectroscopy and timing analysis. Despite tremendous progress in the field, the radiation mechanisms at work in sources such as neutrons stars and black holes are still unclear. The polarization state of the radiation is an observational parameter which brings key additional information about the physical process. This is why most of the projects for the next generation of space missions covering the tens of keV to the MeV region require a polarization measurement capability. A key element enabling this capability is a detector system allowing the identification and characterization of Compton interactions as they are the main process at play. The hard X-ray imaging spectrometer module, developed in CEA with the generic name of Caliste module, is such a detector. In this paper, we present experimental results for two types of Caliste-256 modules, one based on a CdTe crystal, the other one on a CdZnTe crystal, which have been exposed to linearly polarized beams at the European Synchrotron Radiation Facility. These results, obtained at 200-300 keV, demonstrate their capability to give an accurate determination of the polarization parameters (polarization angle and fraction) of the incoming beam. Applying a selection to our data set, equivalent to select 90 degrees Compton scattered interactions in the detector plane, we find a modulation factor Q of 0.78. The polarization angle and fraction are derived with accuracies of approximately 1 degree and 5%. The modulation factor remains larger than 0.4 when essentially no selection is made at all on the data. These results prove that the Caliste-256 modules have performances allowing them to be excellent candidates as detectors with polarimetric capabilities, in particular for future space missions.

  3. Recrystallization in CdTe/CdS A. Romeo, D.L. Batzner, H. Zogg, A.N. Tiwari*

    E-Print Network [OSTI]

    Romeo, Alessandro

    ¯uence on the microstructure of CdTe and photovoltaic properties. Solar cells with ef®ciency of 11.2 and 2.5% are obtainedTe/CdS photovoltaic devices have been obtained with different growth methods [1±3]. Recrys- tallization treatments. Therefore PVD grown CdS layers are used for better reliability despite of the opti- cal losses due to large

  4. Syntheses, crystal structures and characterizations of BaZn(SeO{sub 3}){sub 2} and BaZn(TeO{sub 3})Cl{sub 2}

    SciTech Connect (OSTI)

    Jiang Hailong [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, and the Graduate School of the Chinese Academy of Sciences, Fuzhou 350002 (China); Feng Meiling [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, and the Graduate School of the Chinese Academy of Sciences, Fuzhou 350002 (China); Mao Jianggao [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, and the Graduate School of the Chinese Academy of Sciences, Fuzhou 350002 (China)]. E-mail: mjg@ms.fjirsm.ac.cn

    2006-06-15T23:59:59.000Z

    Two new barium zinc selenite and tellurite, namely, BaZn(SeO{sub 3}){sub 2} and BaZn(TeO{sub 3})Cl{sub 2}, have been synthesized by the solid state reaction. The structure of BaZn(SeO{sub 3}){sub 2} features double chains of [Zn(SeO{sub 3}){sub 2}]{sup 2-} anions composed of four- and eight-member rings which are alternatively along a-axis. The double chains of [Zn{sub 2}(TeO{sub 3}){sub 2}Cl{sub 3}]{sup 3-} anions in BaZn(TeO{sub 3})Cl{sub 2} are formed by Zn{sub 3}Te{sub 3} rings in which each tellurite group connects with three ZnO{sub 3}Cl tetrahedra. BaZn(SeO{sub 3}){sub 2} and BaZn(TeO{sub 3})Cl{sub 2} are wide bandgap semiconductors based on optical diffuse reflectance spectrum measurements. -- Graphical abstract: Two new barium zinc selenite and tellurite, namely, BaZn(SeO{sub 3}){sub 2} and BaZn(TeO{sub 3})Cl{sub 2}, have been synthesized by solid state reaction. The structure of BaZn(SeO{sub 3}){sub 2} features 1D double chains of [Zn(SeO{sub 3}){sub 2}]{sup 2-} anions composed of four- and eight-member rings which are alternatively along a-axis. The 1D double chains of [Zn{sub 2}(TeO{sub 3}){sub 2}Cl{sub 3}]{sup 3-} anions in BaZn(TeO{sub 3})Cl{sub 2} are formed by Zn{sub 3}Te{sub 3} rings in which each tellurite group connects with one ZnO{sub 3}Cl and two ZnO{sub 2}Cl{sub 2} tetrahedra. BaZn(SeO{sub 3}){sub 2} and BaZn(TeO{sub 3})Cl{sub 2} are wide bandgap semiconductors based on optical diffuse reflectance spectrum measurements.

  5. Synthesis of reduced graphene oxide/ZnO nanorods composites on graphene coated PET flexible substrates

    SciTech Connect (OSTI)

    Huang, Lei, E-mail: leihuang@shnu.edu.cn; Guo, Guilue; Liu, Yang; Chang, Quanhong; Shi, Wangzhou

    2013-10-15T23:59:59.000Z

    Graphical abstract: - Highlights: • ZnO nanorods synthesized on CVD-graphene and rGO surfaces, respectively. • ZnO/CVD-graphene and ZnO/rGO form a distinctive porous 3D structure. • rGO/ZnO nanostructures possibility in energy storage devices. - Abstract: In this work, reduced graphene oxide (rGO)/ZnO nanorods composites were synthesized on graphene coated PET flexible substrates. Both chemical vapor deposition (CVD) graphene and reduced graphene oxide (rGO) films were prepared following by hydrothermal growth of vertical aligned ZnO nanorods. Reduced graphene sheets were then spun coated on the ZnO materials to form a three dimensional (3D) porous nanostructure. The morphologies of the ZnO/CVD graphene and ZnO/rGO were investigated by SEM, which shows that the ZnO nanorods grown on rGO are larger in diameters and have lower density compared with those grown on CVD graphene substrate. As a result of fact, the rough surface of nano-scale ZnO on rGO film allows rGO droplets to seep into the large voids of ZnO nanorods, then to form the rGO/ZnO hierarchical structure. By comparison of the different results, we conclude that rGO/ZnO 3D nanostructure is more desirable for the application of energy storage devices.

  6. Anisotropic strain effects on the photoluminescence emission from heteroepitaxial and homoepitaxial nonpolar (Zn,Mg)O/ZnO quantum wells

    SciTech Connect (OSTI)

    Chauveau, J.-M.; Vinter, B. [Centre de Recherche sur l'Hetero-Epitaxie et ses Applications, Centre National de la Recherche Scientifique (CRHEA-CNRS), Rue B. Gregory, F-06560 Valbonne Sophia Antipolis (France); University of Nice Sophia Antipolis, Parc Valrose, F-06102 Nice Cedex 2 (France); Teisseire, M.; Morhain, C.; Deparis, C. [Centre de Recherche sur l'Hetero-Epitaxie et ses Applications, Centre National de la Recherche Scientifique (CRHEA-CNRS), Rue B. Gregory, F-06560 Valbonne Sophia Antipolis (France); Kim-Chauveau, H.

    2011-05-15T23:59:59.000Z

    We report on the properties of nonpolar a-plane (Zn,Mg)O/ZnO quantum wells (QW) grown by molecular beam epitaxy on r plane sapphire and a plane ZnO substrates. For the QWs grown on sapphire, the anisotropy of the lattice parameters of the (Zn,Mg)O barrier gives rise to an unusual in-plane strain state in the ZnO QWs, which induces a strong blue-shift of the excitonic transitions, in addition to the confinement effects. We observe this blue-shift in photoluminescence excitation experiments. The photoluminescence excitation energies of the QWs are satisfactorily simulated when taking into account the variation of the exciton binding energy with the QW width and the residual anisotropic strain. Then we compare the photoluminescence properties of homoepitaxial QWs grown on ZnO bulk substrate and heteroepitaxial QWs grown on sapphire. We show that the reduction of structural defects and the improvement of surface morphology are correlated with a strong enhancement of the photoluminescence properties: reduction of full width at half maximum, strong increase of the luminescence intensities. The comparison convincingly demonstrates the interest of homoepitaxial nonpolar QWs for bright UV emission applications.

  7. FEMALE SINGERS on CD IN THE MUSIC LIBRARY

    E-Print Network [OSTI]

    Lennard, William N.

    FEMALE SINGERS on CD IN THE MUSIC LIBRARY Choose the CATALOGUE, and perform a KEYWORD search, using *GRAHAM, Sandra *GREEN, Patricia # HAMARI, Julia HELLING, Hilke HODGSON, Alfreda HORNE, Marilyn *KRAUSE Librarian Music Library - Western Libraries Western University 2012/04/07 #12;MALE SINGERS ON CD

  8. Optical-Fiber-Based, Time-Resolved Photoluminescence Spectrometer for Thin-Film Absorber Characterization and Analysis of TRPL Data for CdS/CdTe Interface: Preprint

    SciTech Connect (OSTI)

    Kuciauskas, D.; Duenow, J. N.; Kanevce, A.; Li, J. V.; Young, M. R.; Dippo, P.; Levi, D. H.

    2012-06-01T23:59:59.000Z

    We describe the design of a time resolved photoluminescence (TRPL) spectrometer for rapid semiconductor absorber characterization. Simplicity and flexibility is achieved by using single optical fiber to deliver laser pulses and to collect photoluminescence. We apply TRPL for characterization of CdS/CdTe absorbers after deposition, CdCl2 treatment, Cu doping, and back contact formation. Data suggest this method could be applied in various stages of PV device processing. Finally, we show how to analyze TRPL data for CdS/CdTe absorbers by considering laser light absorption depth and intermixing at CdS/CdTe interface.

  9. Primary cutaneous CD30+ large-cell lymphoma presenting as a scrotal plaque

    E-Print Network [OSTI]

    Modi, Sapna; Yang, Deborah J; Sule, Norman; Rosen, Ted

    2009-01-01T23:59:59.000Z

    studies have shown that CD30 negative LCLs have a worseprognosis than CD30+ LCLs [ 4 , 8 ] and should be treatedfrom some primary cutaneous CD30+ LCLs, making the clinical

  10. Strain-dependent photoluminescence behavior in three geometries of CdSe/CdS nanocrystals

    SciTech Connect (OSTI)

    Choi, Charina L; Koski, Kristie J; Sivasankar, Sanjeevi; Alivisatos, A Paul

    2009-05-26T23:59:59.000Z

    In recent years, a new generation of quantum confined colloidal semiconductor structures has emerged, with more complex shapes than simple quantum dots1, 2. These include nanorods3 and tetrapods4. Beyond shape, it is also now possible to spatially vary the electron and hole potentials within these nanoparticles by varying the composition. Examples of these new structures include seeded dots, rods, and tetrapods, which contain a CdSe core embedded within a CdS shell5, 6. These structures may have many uses beyond those envisioned for simple quantum dots, which are frequently employed in luminescent applications7. This paper is concerned with changes in the optoelectronic properties of tetrapods when the arms are bent. We demonstrate that seeded tetrapods can serve as an optical strain gauge, capable of measuring forces on the order of nanonewtons. We anticipate that a nanocrystal strain gauge with optical readout will be useful for applications ranging from sensitive optomechanical devices to biological force investigations.

  11. The BRAF{sup T1799A} mutation confers sensitivity of thyroid cancer cells to the BRAF{sup V600E} inhibitor PLX4032 (RG7204)

    SciTech Connect (OSTI)

    Xing, Joanna [Division of Head and Neck Cancer Research, Department of Otolaryngology and Head and Neck Surgery, The Johns Hopkins University School of Medicine, Baltimore, MD 21231 (United States)] [Division of Head and Neck Cancer Research, Department of Otolaryngology and Head and Neck Surgery, The Johns Hopkins University School of Medicine, Baltimore, MD 21231 (United States); Liu, Ruixin; Xing, Mingzhao [Laboratory for Cellular and Molecular Thyroid Research, Division of Endocrinology and Metabolism, The Johns Hopkins University School of Medicine, Baltimore, MD 21287 (United States)] [Laboratory for Cellular and Molecular Thyroid Research, Division of Endocrinology and Metabolism, The Johns Hopkins University School of Medicine, Baltimore, MD 21287 (United States); Trink, Barry, E-mail: btrink@jhmi.edu [Division of Head and Neck Cancer Research, Department of Otolaryngology and Head and Neck Surgery, The Johns Hopkins University School of Medicine, Baltimore, MD 21231 (United States)] [Division of Head and Neck Cancer Research, Department of Otolaryngology and Head and Neck Surgery, The Johns Hopkins University School of Medicine, Baltimore, MD 21231 (United States)

    2011-01-28T23:59:59.000Z

    Research highlights: {yields} Exciting therapeutic potential has been recently reported for the BRAF{sup V600E} inhibitor PLX4032 in melanoma. {yields} We tested the effects of PLX4032 on the growth of thyroid cancer cells which often harbor the BRAF{sup V600E} mutation. {yields} We observed a potent BRAF{sup V600E}-dependent inhibition of thyroid cancer cells by PLX4032. {yields} We thus demonstrated an important therapeutic potential of PLX4032 for thyroid cancer. -- Abstract: Aberrant signaling of the Ras-Raf-MEK-ERK (MAP kinase) pathway driven by the mutant kinase BRAF{sup V600E}, as a result of the BRAF{sup T1799A} mutation, plays a fundamental role in thyroid tumorigenesis. This study investigated the therapeutic potential of a BRAF{sup V600E}-selective inhibitor, PLX4032 (RG7204), for thyroid cancer by examining its effects on the MAP kinase signaling and proliferation of 10 thyroid cancer cell lines with wild-type BRAF or BRAF{sup T1799A} mutation. We found that PLX4032 could effectively inhibit the MAP kinase signaling, as reflected by the suppression of ERK phosphorylation, in cells harboring the BRAF{sup T1799A} mutation. PLX4032 also showed a potent and BRAF mutation-selective inhibition of cell proliferation in a concentration-dependent manner. PLX4032 displayed low IC{sub 50} values (0.115-1.156 {mu}M) in BRAF{sup V600E} mutant cells, in contrast with wild-type BRAF cells that showed resistance to the inhibitor with high IC{sub 50} values (56.674-1349.788 {mu}M). Interestingly, cells with Ras mutations were also sensitive to PLX4032, albeit moderately. Thus, this study has confirmed that the BRAF{sup T1799A} mutation confers cancer cells sensitivity to PLX4032 and demonstrated its specific potential as an effective and BRAF{sup T1799A} mutation-selective therapeutic agent for thyroid cancer.

  12. One-step electrochemical synthesis of a graphene–ZnO hybrid for improved photocatalytic activity

    SciTech Connect (OSTI)

    Wei, Ang; Xiong, Li; Sun, Li; Liu, Yanjun; Li, Weiwei; Lai, Wenyong; Liu, Xiangmei; Wang, Lianhui [Key Laboratory for Organic Electronics and Information Displays (KLOEID), Nanjing University of Posts and Telecommunications (NUPT), Nanjing 210046 (China); Huang, Wei, E-mail: iamwhuang@njut.edu.cn [Institute of Advanced Materials, Nanjing University of Technology, Nanjing 210009 (China); Dong, Xiaochen, E-mail: iamxcdong@njut.edu.cn [Key Laboratory for Organic Electronics and Information Displays (KLOEID), Nanjing University of Posts and Telecommunications (NUPT), Nanjing 210046 (China); Institute of Advanced Materials, Nanjing University of Technology, Nanjing 210009 (China)

    2013-08-01T23:59:59.000Z

    Graphical abstract: - Highlights: • Graphene–ZnO hybrid was synthesized by one-step electrochemical deposition. • Graphene–ZnO hybrid presents a special structure and wide UV–vis absorption spectra. • Graphene–ZnO hybrid exhibits an exceptionally higher photocatalytic activity for the degradation of dye methylene blue. - Abstract: A graphene–ZnO (G-ZnO) hybrid was synthesized by one-step electrochemical deposition. During the formation of ZnO nanostructure by cathodic electrochemical deposition, the graphene oxide was electrochemically reduced to graphene simultaneously. Scanning electron microscope images, X-ray photoelectron spectroscopy, X-ray diffraction, Raman spectra, and UV–vis absorption spectra indicate the resulting G-ZnO hybrid presents a special structure and wide UV–vis absorption spectra. More importantly, it exhibits an exceptionally higher photocatalytic activity for the degradation of dye methylene blue than that of pure ZnO nanostructure under both ultraviolet and sunlight irradiation.

  13. Fluorescent Dye Encapsulated ZnO Particles with Cell-specific...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    the visible fluorescence emission of the dye or UV fluorescence emission of ZnO, and anti-cancerantibacterial treatments using the selective toxicity of the nanoscale ZnO outer...

  14. ZnS Thin Films Deposited by a Spin Successive Ionic Layer Adsorption...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ZnS Thin Films Deposited by a Spin Successive Ionic Layer Adsorption and Reaction Process. ZnS Thin Films Deposited by a Spin Successive Ionic Layer Adsorption and Reaction...

  15. Pressure Behaviour of the UV and Green Emission Bands in ZnO...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Pressure Behaviour of the UV and Green Emission Bands in ZnO Micro-rods. Pressure Behaviour of the UV and Green Emission Bands in ZnO Micro-rods. Abstract: The pressure behavior of...

  16. Defects in paramagnetic Co-doped ZnO films studied by transmission...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Abstract: We have studied planar defects in epitaxial Co:ZnO dilute magnetic semiconductor thin films deposited on c-plane sapphire (Al2O3) and the Co:ZnOAl2O3...

  17. Mid-Gap Electronic States in Zn1 xMnxO. | EMSL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    measurements were performed on epitaxial Zn1 xMnxO films to investigate the origin of the new mid-gap band that appears upon introduction of Mn2+ into the ZnO lattice. Absorption...

  18. Luminescence Temperature and Pressure Studies of Zn2SiO4 Phosphors...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Temperature and Pressure Studies of Zn2SiO4 Phosphors Doped with Mn2+ and Eu3+ Ions. Luminescence Temperature and Pressure Studies of Zn2SiO4 Phosphors Doped with Mn2+ and Eu3+...

  19. On the room-temperature ferromagnetism of Zn1-xCrxO thin films...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    On the room-temperature ferromagnetism of Zn1-xCrxO thin films deposited by reactive co-sputtering. On the room-temperature ferromagnetism of Zn1-xCrxO thin films deposited by...

  20. An improved understanding of fluorescent Zn(II) sensors and their uses in biological settings

    E-Print Network [OSTI]

    Wong, Brian Alexander

    2009-01-01T23:59:59.000Z

    Chapter 1. An Introduction to Fluorescent Zn(II) Sensors and Their Applications in Biological Systems This chapter opens with an overview of the numerous roles of zinc in biology, with an emphasis on labile Zn(II), that ...

  1. Syngas Conversion to Gasoline-Range Hydrocarbons over Pd/ZnO...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Syngas Conversion to Gasoline-Range Hydrocarbons over PdZnOAl2O3 and ZSM-5 Composite Catalyst System. Syngas Conversion to Gasoline-Range Hydrocarbons over PdZnOAl2O3 and ZSM-5...

  2. Electronic properties of H and D doped ZnO epitaxial films. ...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of H and D doped ZnO epitaxial films. Abstract: ZnO epitaxial films grown by pulsed laser deposition in an ambient of H2 or D2 exhibit qualitatively different electronic...

  3. PdZnAl Catalysts for the Reactions of Water-Gas-Shift, Methanol...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    PdZnAl Catalysts for the Reactions of Water-Gas-Shift, Methanol Steam Reforming, and Reverse-Water-Gas-Shift. PdZnAl Catalysts for the Reactions of Water-Gas-Shift, Methanol Steam...

  4. CO/FTIR Spectroscopic Characterization of Pd/ZnO/Al2O3 Catalysts...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    COFTIR Spectroscopic Characterization of PdZnOAl2O3 Catalysts for Methanol Steam Reforming. COFTIR Spectroscopic Characterization of PdZnOAl2O3 Catalysts for Methanol Steam...

  5. Structural Studies of Al:ZnO Powders and Thin Films | Stanford...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Ingham, Associate Investigator, MacDiarmid Institute for Advanced Materials & Nanotechnology Al-doped ZnO (Al:ZnO) is a promising transparent conducting oxide. We have used...

  6. High mobility ZnO nanowires for terahertz detection applications

    SciTech Connect (OSTI)

    Liu, Huiqiang [State Key Laboratory of Optoelectronic Materials and Technology, Sun Yat-Sen University, Guangdong, Guangzhou 510275 (China); State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials, Southwest University of Science and Technology, Sichuan, Mianyang 621010 (China); Peng, Rufang, E-mail: pengrufang@swust.edu.cn, E-mail: chusheng@mail.sysu.edu.cn; Chu, Shijin [State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials, Southwest University of Science and Technology, Sichuan, Mianyang 621010 (China); Chu, Sheng, E-mail: pengrufang@swust.edu.cn, E-mail: chusheng@mail.sysu.edu.cn [State Key Laboratory of Optoelectronic Materials and Technology, Sun Yat-Sen University, Guangdong, Guangzhou 510275 (China)

    2014-07-28T23:59:59.000Z

    An oxide nanowire material was utilized for terahertz detection purpose. High quality ZnO nanowires were synthesized and field-effect transistors were fabricated. Electrical transport measurements demonstrated the nanowire with good transfer characteristics and fairly high electron mobility. It is shown that ZnO nanowires can be used as building blocks for the realization of terahertz detectors based on a one-dimensional plasmon detection configuration. Clear terahertz wave (?0.3?THz) induced photovoltages were obtained at room temperature with varying incidence intensities. Further analysis showed that the terahertz photoresponse is closely related to the high electron mobility of the ZnO nanowire sample, which suggests that oxide nanoelectronics may find useful terahertz applications.

  7. Process for fabricating ZnO-based varistors

    DOE Patents [OSTI]

    Lauf, Robert J. (Oak Ridge, TN)

    1985-01-01T23:59:59.000Z

    The invention is a process for producing ZnO-based varistors incorporating a metal oxide dopant. In one form, the invention comprises providing a varistor powder mix of colloidal particles of ZnO and metal-oxide dopants including Bi.sub.2 O.sub.3. The mix is hot-pressed to form a compact at temperatures below 850.degree. C. and under conditions effecting reduction of the ZnO to sub-stoichiometric oxide. This promotes densification while restricting liquid formation and grain growth. The compact then is heated under conditions restoring the zinc oxide to stoichiometric composition, thus improving the varistor properties of the compact. The process produces fine-grain varistors characterized by a high actual breakdown voltage and a high average breakdown voltage per individual grain boundary.

  8. Nitrogen is a deep acceptor in ZnO

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    McCluskey, M.D. [Washington State Univ., Pullman, WA (United States); Tarun, M.C. [Washington State Univ., Pullman, WA (United States); Iqbal, M. Zafar [COMSATS Institute of Information Technology, Islamabad (Pakistan)

    2011-04-14T23:59:59.000Z

    Zinc oxide is a promising material for blue and UV solid-state lighting devices, among other applications. Nitrogen has been regarded as a potential p-type dopant for ZnO. However, recent calculations [Lyons, Janotti, and Van de Walle, Appl. Phys. Lett. 95, 252105 (2009)] indicate that nitrogen is a deep acceptor. This paper presents experimental evidence that nitrogen is, in fact, a deep acceptor and therefore cannot produce p-type ZnO. A broad photoluminescence (PL) emission band near 1.7 eV, with an excitation onset of ~2.2 eV, was observed, in agreement with the deep-acceptor model of the nitrogen defect. The deep-acceptor behavior can be explained by the low energy of the ZnO valence band relative to the vacuum level.

  9. Structural recovery of ion implanted ZnO nanowires G. Perillat-Merceroz,1, 2, a)

    E-Print Network [OSTI]

    Boyer, Edmond

    applications, ZnO nanowires are studied for making light- emitting diodes (LEDs) because of the advantages

  10. Heat treatment effects on microstructure and magnetic properties of MnZn ferrite powders

    E-Print Network [OSTI]

    Volinsky, Alex A.

    Heat treatment effects on microstructure and magnetic properties of Mn­Zn ferrite powders Ping Hu Available online 6 September 2009 Keywords: Mn­Zn ferrite Heat treatment Microstructure Magnetic property a b s t r a c t Mn­Zn ferrite powders (Mn0.5Zn0.5Fe2O4) were prepared by the nitrate­citrate auto

  11. Magneto-optical Kerr rotation enhancement in CoZnO inhomogeneous magnetic semiconductor

    E-Print Network [OSTI]

    Liu, J. Ping

    impurity doping, the doped ZnO can be used as transparent electrodes in solar cells and flat panel display

  12. D= DOE/RG-0067

    Office of Environmental Management (EM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33 1112011AT&T,Office of Policy, OAPM | Department ofCommunications Infrastructure2D=

  13. Effect of ZnO seed layer on the morphology and optical properties of ZnO nanorods grown on GaN buffer layers

    SciTech Connect (OSTI)

    Nandi, R., E-mail: rajunandi@iitb.ac.in; Mohan, S., E-mail: rajunandi@iitb.ac.in; Major, S. S. [Department of Physics, Indian Institute of Technology Bombay, Mumbai - 400076 (India); Srinivasa, R. S. [Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology Bombay, Mumbai - 400076 (India)

    2014-04-24T23:59:59.000Z

    ZnO nanorods were grown by chemical bath deposition on sputtered, polycrystalline GaN buffer layers with and without ZnO seed layer. Scanning electron microscopy and X-ray diffraction show that the ZnO nanorods on GaN buffer layers are not vertically well aligned. Photoluminescence spectrum of ZnO nanorods grown on GaN buffer layer, however exhibits a much stronger near-band-edge emission and negligible defect emission, compared to the nanorods grown on ZnO buffer layer. These features are attributed to gallium incorporation at the ZnO-GaN interface. The introduction of a thin (25 nm) ZnO seed layer on GaN buffer layer significantly improves the morphology and vertical alignment of ZnO-NRs without sacrificing the high optical quality of ZnO nanorods on GaN buffer layer. The presence of a thick (200 nm) ZnO seed layer completely masks the effect of the underlying GaN buffer layer on the morphology and optical properties of nanorods.

  14. Structure of graphene oxide dispersed with ZnO nanoparticles

    SciTech Connect (OSTI)

    Yadav, Rishikesh, E-mail: rishikesh.yadav62@gmail.com; Pandey, Devendra K., E-mail: devendrakphy@gmail.com [School of Nanotechnology, Rajiv Gandhi Proudyogiki Vishwavidalaya, Bhopal, M.P. (India); Khare, P. S., E-mail: purnimaswarup@hotmail.com [Department of Physics, Rajiv Gandhi Proudyogiki Vishwavidalaya, Bhopal M.P. (India)

    2014-10-15T23:59:59.000Z

    Graphene has been proposed as a promising two-dimensional nanomaterial with outstanding electronic, optical, thermal and mechanical properties for many applications. In present work a process of dispersion of graphene oxide with ZnO nanoparticles in ethanol solution with different pH values, have been studied. Samples have been characterized by XRD, SEM, PL, UV-visible spectroscopy and particles size measurement. The results analysis indicates overall improved emission spectrum. It has been observed that the average diameter of RGO (Reduced Graphene Oxide) decreases in presence of ZnO nanoparticles from 3.8?m to 0.41?m.

  15. Zinc Fertilization Plus Liming to Reduce Cadmium Uptake by Romaine Lettuce on Cd-Mineralized Lockwood Soil

    E-Print Network [OSTI]

    Chaney, Rufus L; Green, Carrie E.; Ajwa, Husein A; Smith, Richard F

    2009-01-01T23:59:59.000Z

    by emissions from zinc smelters. Trace Subst. Environ.1999) who studied Zn-smelter or mine waste contaminated orgrowing Romaine lettuce on Zn-smelter contaminated soils in

  16. Effect of the (OH) Surface Capping on ZnO Quantum Dots

    E-Print Network [OSTI]

    Nabben, Reinhard

    in air at different temperatures from 150­500 C for 30 min. In comparison, highly purified bulk Zn is related to oxygen deficiency [1]; the other is a much narrower ultraviolet (UV) emission band at around, compared with good quality ZnO single crystals or ZnO powders, the UV bandgap luminescence in quantum dots

  17. Characterization of surface and nonlinear elasticity in wurtzite ZnO nanowires J. Yvonnet,1, a)

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Characterization of surface and nonlinear elasticity in wurtzite ZnO nanowires J. Yvonnet,1, a) A­25 . Several first-principles studies have been conducted on wurtzite ZnO surfaces26­32 . Marana et al.33 have effects and their relation to size-dependent effective properties of ZnO wurtzite nanowires, by means

  18. Zn exchangeability in soils1 Zinc speciation and isotopic exchangeability in soils polluted with3

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    -step selective sequential extraction (SSE) in incubated soils30 and by identifying Zn forms in soils using were extracted in the 4th step of37 the SSE, while the rest of the 3rd pool was extracted in the final. Other species included strongly sorbed Zn species41 and Zn species in crystalline minerals. The EXAFS

  19. Corrosion of, and cellular responses to MgZnCa bulk metallic glasses Xuenan Gu a

    E-Print Network [OSTI]

    Zheng, Yufeng

    Corrosion of, and cellular responses to Mg­Zn­Ca bulk metallic glasses Xuenan Gu a , Yufeng Zheng a: Magnesium alloy Bulk metallic glass Mechanical property Corrosion Cytotoxicity a b s t r a c t Mg­Zn­Ca bulk, mechanical testing, corrosion and cytotoxicity tests. It was found that the Mg66Zn30Ca4 sample presents

  20. Remote plasma enhanced atomic layer deposition of ZnO for thin film electronic applications

    E-Print Network [OSTI]

    Zheludev, Nikolay

    Remote plasma enhanced atomic layer deposition of ZnO for thin film electronic applications S: Available online 28 May 2012 Keywords: Remote plasma Atomic layer deposition (ALD) ZnO Thin film transistor of various reactant plasma parameters of remote plasma enhanced ALD (PEALD) on the ZnO thin film properties

  1. Process Development for High Voc CdTe Solar Cells

    SciTech Connect (OSTI)

    Ferekides, C. S.; Morel, D. L.

    2011-05-01T23:59:59.000Z

    This is a cumulative and final report for Phases I, II and III of this NREL funded project (subcontract # XXL-5-44205-10). The main research activities of this project focused on the open-circuit voltage of the CdTe thin film solar cells. Although, thin film CdTe continues to be one of the leading materials for large-scale cost-effective production of photovoltaics, the efficiency of the CdTe solar cells have been stagnant for the last few years. This report describes and summarizes the results for this 3-year research project.

  2. agonist cd40 antibody: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    (15-17) and that the interaction between CD2 and LFA-3 can mediate adhesion of J Clark; Debbie A Law; David J Paterson; Michael Puklavec; Alan; F. Williams 1988-01-01 405...

  3. antigens cd: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    in adulthood of autoreactive T cells specific to that antigen. The renal-specific ... Marshall, Naomi Jane 2009-01-01 42 Cardiovasc Res . Author manuscript A CD31-derived...

  4. High-efficiency large-area CdTe panels

    SciTech Connect (OSTI)

    Albright, S.P.; Chamberlin, R.R.; Jordan, J.F. (Photon Energy, Inc., El Paso, TX (USA))

    1990-11-01T23:59:59.000Z

    The objective of this three year effort has been to develop an improved materials technology and fabrication process for limited volume production of 1 ft{sup 2} and 4 ft{sup 2} CdS/CdTe photovoltaic modules. The module stability objective by the end of this three year subcontract was to develop techniques to provide ten year life exploration with no greater than 10% degradation. In order to achieve these efficiency and stability objectives, the research program has been separated into tasks including: (1) analysis and characterization of CdS/CdTe Devices; (2) performance optimization on small cells; (3) encapsulation and stability testing; and (4) module efficiency optimization. 27 refs., 18 figs., 3 tabs.

  5. CdTe Photovoltaics: Real and Perceived EHS Risks

    E-Print Network [OSTI]

    Ohta, Shigemi

    a comprehensive collection and recycling program would not reduce the environmental impacts of these panels result in Cd (gaseous) emissions of 0.5g/GWh, equivalent to that of a coal fired power plant

  6. al cd cu: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    for improving performance Materials Science Websites Summary: at the CdSCuInSe 2 thin-film solar-cell heterojunction Appl. Phys. Lett. 79, 4482 (2001); 10, crystalline...

  7. Strategies for recycling CdTe photovoltaic modules

    SciTech Connect (OSTI)

    Eberspacher, C.; Gay, C.F. [UNISUN, Newbury Park, CA. (United States); Moskowitz, P.D. [Brookhaven National Lab., Upton, NY (United States)

    1994-12-31T23:59:59.000Z

    Recycling end-of-life cadmium telluride (CdTe) photovoltaic (PV) modules may enhance the competitive advantage of CdTe PV in the marketplace, but the experiences of industries with comparable Environmental, Health and Safety (EH&S) challenges suggest that collection and recycling costs can impose significant economic burdens. Customer cooperation and pending changes to US Federal law may improve recycling economics.

  8. Defect Chemistry Study of Nitrogen Doped ZnO Thin Films

    SciTech Connect (OSTI)

    Miami University: Dr. Lei L. Kerr (PI, PD) Wright State University: Dr. David C. Look (PI) and Dr. Zhaoqiang Fang (Co-PI)

    2009-11-29T23:59:59.000Z

    Our team has investigated the defect chemistry of ZnO:N and developed a thermal evaporation (vapor-phase) method to synthesis p-type ZnO:N. Enhanced p-type conductivity of nitrogen doped ZnO via nano/micro structured rods and Zn-rich Co-doping process were studied. Also, an extended X-Ray absorption fine structure study of p-type nitrogen doped ZnO was conducted. Also reported are Hall-effect, photoluminescence, and DLTS studies.

  9. ZnO Nanotube Based Dye-Sensitized Solar Cells

    E-Print Network [OSTI]

    ZnO Nanotube Based Dye-Sensitized Solar Cells Alex B. F. Martinson,, Jeffrey W. Elam, Joseph T templated by anodic aluminum oxide for use in dye-sensitized solar cells (DSSCs). Atomic layer deposition of the best dye- sensitized solar cells (DSSCs) is the product of a dye with moderate extinction

  10. SIGNS IN THE cd-INDEX OF EULERIAN PARTIALLY ORDERED SETS

    E-Print Network [OSTI]

    Bayer, Margaret M.

    2000-12-28T23:59:59.000Z

    in the cd-index. The cd-index of a polytope has all positive entries. An important open problem is to give the broadest natural class of Eulerian posets having nonnegative cd-index. This paper completely determines which entries of the cd...

  11. Fabrication of stable, large-area, thin-film CdTe photovoltaic modules. Annual subcontract report, 10 May 1991--9 May 1992

    SciTech Connect (OSTI)

    Nolan, J.F.; Meyers, P.V. [Solar Cells, Inc., Toledo, OH (United States)

    1992-09-01T23:59:59.000Z

    Solar Cells, Inc (SCI) has a program to produce 60 cm X 120 cm solar modules based on CdTe films. The method of choice for semiconductor deposition is condensation from high temperature vapor`s. Early work focussed on Close Spaced Sublimation and Chemical Vapor Deposition using elemental sources, but later equipment designs no longer strictly conform to either category. Small area efficiency has been confirmed by NREL at 9.3% on a 0.22 cm{sup 2} device (825 mV Voc, 18.2 mA/cm{sup 2} Jsc, and 0.62 FF) deposited on a 100 cm{sup 2} substrate. On 8 cell, 64 cm{sup 2} submodules, the best result to date is 7.3% (5.9 V Voc, 130 mA Isc, and 0.61 FF). CdS, CdTe, and ZnTe films have been deposited onto 60 cm X 120 cm substrates - single cells produced from this material have exceeded 8% efficiency, 64 cm{sup 2} submodules have exceeded 5%. Module efficiency is limited by mechanical defects - mostly shunts - associated with processing after deposition of the semiconductor layer`s. Present best result is 1.4% total area efficiency. In anticipation of more advanced designs, CdTe films have also been deposited from apparatus employing elemental sources. This project is in an early stage and has produced only rudimentary results. A pro-active Safety, Health, Environmental and Disposal program has been developed. Results to date indicate that both employees and the environment have been protected against overexposure to hazards including toxic chemicals.

  12. The effects of high temperature processing on the structural and optical properties of oxygenated CdS window layers in CdTe solar cells

    SciTech Connect (OSTI)

    Paudel, Naba R.; Grice, Corey R.; Xiao, Chuanxiao; Yan, Yanfa [Department of Physics and Astronomy, and Wright Center for Photovoltaics Innovation and Commercialization, The University of Toledo, Toledo, Ohio 43606 (United States)

    2014-07-28T23:59:59.000Z

    High efficiency CdTe solar cells typically use oxygenated CdS (CdS:O) window layers. We synthesize CdS:O window layers at room temperature (RT) and 270?°C using reactive sputtering. The band gaps of CdS:O layers deposited at RT increase when O{sub 2}/(O{sub 2}?+?Ar) ratios in the deposition chamber increase. On the other hand, the band gaps of CdS:O layers deposited at 270?°C decrease as the O{sub 2}/(O{sub 2}?+?Ar) ratios increase. Interestingly, however, our high temperature closed-space sublimation (CSS) processed CdTe solar cells using CdS:O window layers deposited at RT and 270?°C exhibit very similar cell performance, including similar short-circuit current densities. To understand the underlying reasons, CdS:O thin films deposited at RT and 270?°C are annealed at temperatures that simulate the CSS process of CdTe deposition. X-ray diffraction, atomic force microscopy, and UV-visible light absorption spectroscopy characterization of the annealed films reveals that the CdS:O films deposited at RT undergo grain regrowth and/or crystallization and exhibit reduced band gaps after the annealing. Our results suggest that CdS:O thin films deposited at RT and 270?°C should exhibit similar optical properties after the deposition of CdTe layers, explaining the similar cell performance.

  13. First principle study of elastic and thermodynamic properties of ZrZn{sub 2} and HfZn{sub 2} under high pressure

    SciTech Connect (OSTI)

    Sun, Na; Zhang, Xinyu, E-mail: jiaqianqin@gmail.com; Ning, Jinliang; Zhang, Suhong; Liang, Shunxing; Ma, Mingzhen; Liu, Riping [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China); Qin, Jiaqian, E-mail: jiaqianqin@gmail.com [Metallurgy and Materials Science Research Institute, Chulalongkorn University, Bangkok 10330 (Thailand)

    2014-02-28T23:59:59.000Z

    A comprehensive investigation of the structural, elastic, and thermodynamic properties for Laves-phases ZrZn{sub 2} and HfZn{sub 2} are conducted using density functional total energy calculations combined with the quasi-harmonic Debye model. The optimized lattice parameters of ZrZn{sub 2} and HfZn{sub 2} compare well with available experimental values. We estimated the mechanical behaviors of both compounds under compression, including mechanical stability, Young's modulus, Poisson's ratio, ductility, and anisotropy. Additionally, the thermodynamic properties as a function of pressure and temperature are analyzed and found to be in good agreement with the corresponding experimental data.

  14. Nano Res. 2012, 5(6): 412420412 Reshaping the Tips of ZnO Nanowires by Pulsed Laser

    E-Print Network [OSTI]

    Wang, Zhong L.

    Nano Res. 2012, 5(6): 412­420412 Reshaping the Tips of ZnO Nanowires by Pulsed Laser Irradiation to the body of the ZnO nanowire, and that the center of the sphere is hollow. The growth mechanism of the hollow ZnO nanospheres is proposed to involve laser-induced ZnO evaporation immediately followed by re

  15. Ordered zinc-vacancy induced Zn0.75Ox nanophase structure Yong Ding, Rusen Yang, Zhong Lin Wang *

    E-Print Network [OSTI]

    Wang, Zhong L.

    induced by Zn-vacancy has been discovered to grow on wurtzite ZnO nanobelts. The superstructure grows epitaxial from the f0110g surface of the wurtzite ZnO nanobelts and can be fitted as an orthorhombic surfaces of the wurtzite structured ZnO nanobelts and can be fitted as an orthorhombic structure

  16. Resorption Rate Tunable Bioceramic: Si, Zn-Modified Tricalcium Phosphate

    SciTech Connect (OSTI)

    Xiang Wei

    2006-08-09T23:59:59.000Z

    This dissertation is organized in an alternate format. Several manuscripts which have already been published or are to be submitted for publication have been included as separate chapters. Chapter 1 is a general introduction which describes the dissertation organization and introduces the human bone and ceramic materials as bone substitute. Chapter 2 is the background and literature review on dissolution behavior of calcium phosphate, and discussion of motivation for this research. Chapter 3 is a manuscript entitled ''Si,Zn-modified tricalcium phosphate: a phase composition and crystal structure study'', which was published in ''Key Engineering Materials'' [1]. Chapter 4 gives more crystal structure details by neutron powder diffraction, which identifies the position for Si and Zn substitution and explains the stabilization mechanism of the structure. A manuscript entitled ''Crystal structure analysis of Si, Zn-modified Tricalcium phosphate by Neutron Powder Diffraction'' will be submitted to Biomaterials [2]. Chapter 5 is a manuscript, entitled ''Dissolution behavior and cytotoxicity test of Si, Zn-modified tricalcium phosphate'', which is to be submitted to Biomaterials [3]. This paper discusses the additives effect on the dissolution behavior of TCP, and cytotoxicity test result is also included. Chapter 6 is the study of hydrolysis process of {alpha}-tricalcium phosphate in the simulated body fluid, and the phase development during drying process is discussed. A manuscript entitled ''Hydrolysis of {alpha}-tricalcium phosphate in simulated body fluid and phase transformation during drying process'' is to be submitted to Biomaterials [4]. Ozan Ugurlu is included as co-authors in these two papers due to his TEM contributions. Appendix A is the general introduction of the materials synthesis, crystal structure and preliminary dissolution result. A manuscript entitled ''Resorption rate tunable bioceramic: Si and Zn-modified tricalcium phosphate'' was published in Ceramic Engineering and Science Proceedings (the 29th International Conference on Advanced Ceramics and Composites - Advances in Bioceramics and Biocomposites) [5].

  17. Structural and optical properties of MgO doped ZnO

    SciTech Connect (OSTI)

    Verma, Kavita; Shukla, S.; Varshney, Dinesh, E-mail: vdinesh33@rediffmail.com [School of Physics, Vigyan Bhavan, Devi Ahilya University, Khandwa Road Campus, Indore-452001 (India); Varshney, M. [Department of Physics, M. B. Khalsa College, Raj Mohallah, Indore-452002 (India); Asthana, A. [Department of Chemistry, Govt. B. V. T. PG Autonomous College, Durg- 491001 (India)

    2014-04-24T23:59:59.000Z

    Samples of ZnO, Zn{sub 0.5}Mg{sub 0.5}O and MgO were prepared by co-precipitation method. X-ray diffraction (XRD) pattern infers that the sample of ZnO is in single-phase wurtzite structure (hexagonal phase, space group P6{sub 3}mc), MgO crystallizes in cubic Fd3m space group and Zn{sub 0.5}Mg{sub 0.5}O represents mixed nature of ZnO and MgO lattices. Similar features were observed from Raman spectroscopy. The energy band gaps estimated from UV-Vis spectroscopy are found to be 4.21 and 3.42 eV for ZnO and Zn{sub 0.5}Mg{sub 0.5}O samples respectively.

  18. Coulomb interaction of acceptors in Cd{sub 1?x}Mn{sub x}Te/CdTe quantum dot

    SciTech Connect (OSTI)

    Kalpana, P.; Nithiananthi, P., E-mail: kjkumar-gri@rediffmail.com; Jayakumar, K., E-mail: kjkumar-gri@rediffmail.com [Department of Physics, Gandhigram Rural University, Gandhigram-624302, TamilNadu (India); Reuben, A. Merwyn Jasper D. [Department of Physics, School of Engineering, Saveetha University, Thandalam, Chennai- 600104, TamilNadu (India)

    2014-04-24T23:59:59.000Z

    The investigation on the effect of confining potential like isotropic harmonic oscillator type potential on the binding and the Coulomb interaction energy of the double acceptors in the presence of magnetic field in a Cd{sub 1?x}Mn{sub x}Te/CdTe Spherical Quantum Dot has been made for the Mn ion composition x=0.3 and compared with the results obtained from the square well type potential using variational procedure in the effective mass approximation.

  19. Theoretical study of syngas hydrogenation to methanol on the polar Zn-terminated ZnO(0001) surface

    SciTech Connect (OSTI)

    Zhao, Ya-Fan; Rousseau, Roger J.; Li, Jun; Mei, Donghai

    2012-08-02T23:59:59.000Z

    Methanol synthesis from syngas (CO/CO2/H2) hydrogenation on the perfect Zn–terminated polar ZnO(0001) surface have been investigated using periodic density functional theory calculations. Our results show that direct CO2 hydrogenation to methanol on the perfect ZnO(0001) surface is unlikely because in the presence of surface atomic H and O the highly stable formate (HCOO) and carbonate (CO3) readily produced from CO2 with low barriers 0.11 and 0.09 eV will eventually accumulate and block the active sites of the ZnO(0001) surface. In contrast, methanol synthesis from CO hydrogenation is thermodynamically and kinetically feasible on the perfect ZnO(0001) surface. CO can be consecutively hydrogenated into formyl (HCO), formaldehyde (H2CO), methoxy (H3CO) intermediates, leading to the final formation of methanol (H3COH). The reaction route via hydroxymethyl (H2COH) intermediate, a previously proposed species on the defected O–terminated ZnO( ) surface, is kinetically inhibited on the perfect ZnO(0001) surface. The rate-determining step in the consecutive CO hydrogenation route is the hydrogenation of H3CO to H3COH. We also note that this last hydrogenation step is pronouncedly facilitated in the presence of water by lowering the activation barrier from 1.02 to 0.55 eV. This work was supported by the U.S. Department of Energy Office of Basic Energy Sciences, Division of Chemical Sciences, Biosciences and Geosciences, and performed at EMSL, a national scientific user facility sponsored by the Department of Energy’s Office of Biological and Environmental Research located at Pacific Northwest National Laboratory (PNNL). Computational resources were provided at EMSL and the National Energy Research Scientific Computing Center at Lawrence Berkeley National Laboratory. J. Li and Y.-F. Zhao were also financially supported by the National Natural Science Foundation of China (Nos. 20933003 and 91026003) and the National Basic Research Program of China (No. 2011CB932400). Y.-F. Zhao acknowledges the fellowship from PNNL.

  20. Identification of phosphatidylserine as a ligand for the CD300a immunoreceptor

    SciTech Connect (OSTI)

    Nakahashi-Oda, Chigusa; Tahara-Hanaoka, Satoko; Honda, Shin-ichiro [Department of Immunology, Division of Biomedical Sciences, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575 (Japan) [Department of Immunology, Division of Biomedical Sciences, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575 (Japan); Japan Science and Technology Agency, CREST, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575 (Japan); Shibuya, Kazuko [Department of Immunology, Division of Biomedical Sciences, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575 (Japan)] [Department of Immunology, Division of Biomedical Sciences, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575 (Japan); Shibuya, Akira, E-mail: ashibuya@md.tsukuba.ac.jp [Department of Immunology, Division of Biomedical Sciences, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575 (Japan) [Department of Immunology, Division of Biomedical Sciences, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575 (Japan); Japan Science and Technology Agency, CREST, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575 (Japan)

    2012-01-06T23:59:59.000Z

    Highlights: Black-Right-Pointing-Pointer CD300a is a new phosphatidylserine receptor expressed on myeloid cells. Black-Right-Pointing-Pointer Phosphatidylserine delivers a signal for recruitment of SHP-1 by CD300a in mast cells. Black-Right-Pointing-Pointer The CD300a/phosphatidylserine interaction is blocked by MFG-E8 or anti-CD300a antibody. -- Abstract: CD300a is a member of CD300 family molecules consisting of seven genes on human chromosome 17 and nine genes in mouse chromosome 11. CD300a has a long cytoplasmic region containing the consensus immunoreceptor tyrosine-based inhibitory motif (ITIM) sequence. Upon crosslinking with antibodies against CD300a, CD300a mediates an inhibitory signal in myeloid cells. However, the ligand for CD300a has not been identified and the physiological role of CD300a remained unclear. Here, we demonstrate that the chimeric fusion protein of CD300a extracellular domain with the Fc portion of human IgG specifically bound phosphatidylserine (PS), which is exposed on the outer leaflet of the plasma membrane of apoptotic cells. PS binding to CD300a induced SHP-1 recruitment by CD300a in mast cells in response to LPS. These results indicated that CD300a is a new PS receptor.

  1. Mesoporous TiO2 beads for high efficiency CdS/ CdSe quantum dot co-sensitized solar cells

    E-Print Network [OSTI]

    Cao, Guozhong

    ) as a derivative of dye-sensitized solar cells (DSCs) have attracted considerable attention and been regardedMesoporous TiO2 beads for high efficiency CdS/ CdSe quantum dot co-sensitized solar cells Ru Zhou for a CdS/CdSe quantum dot (QD) co-sensitized solar cell, which was constructed with the mesoporous TiO2

  2. Properties of electrospun CdS and CdSe filled poly(methyl methacrylate) (PMMA) nanofibres

    SciTech Connect (OSTI)

    Mthethwa, T.P. [University of Johannesburg, Department of Chemical Technology, P.O. Box 17011, Doornfontein 2028 (South Africa)] [University of Johannesburg, Department of Chemical Technology, P.O. Box 17011, Doornfontein 2028 (South Africa); Moloto, M.J., E-mail: mmoloto@uj.ac.za [University of Johannesburg, Department of Chemical Technology, P.O. Box 17011, Doornfontein 2028 (South Africa); De Vries, A.; Matabola, K.P. [CSIR Materials Science and Manufacturing, 4 Gomery avenue, Summerstrand, Port Elizabeth 6000 (South Africa)] [CSIR Materials Science and Manufacturing, 4 Gomery avenue, Summerstrand, Port Elizabeth 6000 (South Africa)

    2011-04-15T23:59:59.000Z

    Graphical abstract: SEM images of CdS/PMMA showing coiling as loading of CdS nanoparticles is increased. Thermal stability is increased with increase in %loading of both CdS and CdSe nanoparticles. Research highlights: {yields} TOPO-capped CdS and HDA-capped CdSe nanoparticles were synthesized and fully characterized. {yields} The nanoparticles were mixed with the polymer, PMMA using electrospinning technique using 2, 5 and 10% weight loadings. {yields} The mixture was spun to produce fibres with optical and thermal properties showing significant change and also the increase in loading causing bending or spiraling. {yields} Both TEM images for nanoparticles and SEM for fibres shows the morphology and sizes of the particles. -- Abstract: Electrospinning technique was used to fabricate poly(methyl methacrylate) (PMMA) fibres incorporating CdS and CdSe quantum dots (nanoparticles). Different nanoparticle loadings (2, 5 and 10 wt% with respect to PMMA) were used and the effect of the quantum dots on the properties of the fibres was studied. The optical properties of the hybrid composite fibres were investigated by photoluminescence and UV-vis spectrophotometry. Scanning electron microscopy (SEM), X-ray diffraction and FTIR spectrophotometry were also used to investigate the morphology and structure of the fibres. The optical studies showed that the size-tunable optical properties can be achieved in the polymer fibres by addition of quantum dots. SEM images showed that the morphologies of the fibres were dependent on the added amounts of quantum dots. A spiral type of morphology was observed with an increase in the concentration of CdS and CdSe nanoparticles. Less beaded structures and bigger diameter fibres were obtained at higher quantum dot concentrations. X-ray diffractometry detected the amorphous peaks of the polymer and even after the quantum dots were added and the FTIR analysis shows that there was no considerable interaction between the quantum dots and the polymer fibres at low concentration of quantum dots however at higher concentrations some interactions were observed which shows that QDs were present on the surfaces of the fibres.

  3. Transparent Conducting ZnO Thin Films Doped with Al and Mo

    SciTech Connect (OSTI)

    Duenow, J.; Gessert, T.; Wood, D.; Young, D.; Coutts, T.

    2007-01-01T23:59:59.000Z

    Transparent conducting oxide (TCO) thin films are a vital part of photovoltaic cells, flat-panel displays, and electrochromic windows. ZnO-based TCOs, due to the relative abundance of Zn, may reduce production costs compared to those of the prevalent TCO In2O3:Sn (ITO). Undoped ZnO, ZnO:Al (0.5, 1, and 2 wt.% Al2O3), and ZnO:Mo (2 wt.%) films were deposited by RF magnetron sputtering. Controlled incorporation of H2 in the Ar sputtering ambient increased mobility of undoped ZnO by a factor of ~20 to 48 cm2V-1s-1. H2 also appears to catalyze ionization of dopants. This enabled lightly doped ZnO:Al to provide comparable conductivity to the standard 2 wt.%-doped ZnO:Al while demonstrating reduced infrared absorption. Mo was found to be an n-type dopant of ZnO, though material properties did not match those of ZnO:Al. Scattering mechanisms were investigated using temperature-dependent Hall measurements and the method of four coefficients. This abstract is subject to government rights.

  4. Growth of Single- and Bilayer ZnO on Au(111) and Interaction with Copper

    SciTech Connect (OSTI)

    Deng, Xingyi; Yao, Kun; Sun, Keju; Li, Wei-Xue; Lee, Junseok; Matranga, Christopher

    2013-05-30T23:59:59.000Z

    The stoichiometric single- and bi-layer ZnO(0001) have been prepared by reactive deposition of Zn on Au(111) and studied in detail with X-ray photoelectron spectroscopy, scanning tunneling microscopy, and density functional theory calculations. Both single- and bi-layer ZnO(0001) adopt a planar, graphite-like structure similar to freestanding ZnO(0001) due to the weak van der Waals interactions dominating their adhesion with the Au(111) substrate. At higher temperature, the single-layer ZnO(0001) converts gradually to bi-layer ZnO(0001) due to the twice stronger interaction between two ZnO layers than the interfacial adhesion of ZnO with Au substrate. It is found that Cu atoms on the surface of bi-layer ZnO(0001) are mobile with a diffusion barrier of 0.31 eV, and likely to agglomerate and form nanosized particles at low coverages; while Cu atoms tend to penetrate a single layer of ZnO(0001) with a barrier of 0.10 eV, resulting in a Cu free surface.

  5. ZnS and ZnSe immersion gratings for astronomical high-resolution spectroscopy - evaluation of internal attenuation of bulk materials in the short NIR region

    SciTech Connect (OSTI)

    Ikeda, Y; Kobayashi, N; Kondo, S; Yasui, C; Kuzmenko, P J; Tokoro, H; Terada, H

    2009-08-12T23:59:59.000Z

    We measure the internal attenuation of bulk crystals of CVD-ZnS, CVD-ZnSe, Si, and GaAs, in the short near-infrared (sNIR) region to evaluate the possibility of astronomical immersion gratings with those high refractive index materials. We confirm that multispectral grade CVD-ZnS and CVD-ZnSe are best suited for the immersion gratings, with the smallest internal attenuation of {alpha}{sub att} = 0.01-0.03 cm{sup -1} among the major candidates. The measured attenuation is roughly in proportion to {lambda}{sup -2}, suggesting it is dominated by bulk scattering due to the polycrystalline grains rather than by absorption. The total transmittance in the immersion grating is estimated to be at least > 80 %, even for the spectral resolution of R = 300,000. Two potential problems, the scattered light by the bulk material and the degradation of the spectral resolution due to the gradient illumination in the diffracted beam, are investigated and found to be negligible for usual astronomical applications. Since the remaining problem, the difficulty of cutting grooves on CVD-ZnS and CVD-ZnSe, has recently been overcome by the nanoprecision fly-cutting technique, ZnS and ZnSe immersion gratings for astronomy can be technically realized.

  6. Experimental evidence of V{sub O}?Zn{sub i} complex to be intrinsic donor in bulk ZnO

    SciTech Connect (OSTI)

    Asghar, M.; Mahmood, K. [Department of Physics, The Islamia University of Bahawalpur 63100 (Pakistan); Hasan, M.-A; Tsu, R.; Ferguson, I. T. [Department of Electrical and Computer Engineering, University of North Carolina Charlotte, NC 28223 (United States)

    2014-02-21T23:59:59.000Z

    Theoretical evidence of V{sub O}?Zn{sub i} to be a native donor in bulk ZnO has been under debate. To resolve the issue, we annealed several pieces of as grown zinc rich n-type ZnO thin film having N{sub D} ? 3.26 × 10{sup 17} cm{sup ?3} grown by molecular beam epitaxy on Si (001) substrate in oxygen environment at 500°C – 800°C, keeping a step of 100°C for one hour, each. Room temperature Hall measurements demonstrated that free donor concentration decreased exponentially and Arrhenius plot yielded activation energy to be 1.2±0.02 eV. This value is in an agreement with the theoretically reported activation energy of V{sub O}?Zn{sub i} donor complex in ZnO.

  7. Acceptors in ZnO nanocrystals S. T. Teklemichael,1

    E-Print Network [OSTI]

    McCluskey, Matthew

    as a buffer layer for growth of GaN-based devices,2 as a transparent conductive oxide Ref. 3 in solar cells,4- drate Zn CH3COO 2·2H2O and sodium hydrogen carbon- ate NaHCO3 are reacted at 200 °C for 3 h in an open cooling down to low tempera- ture. Electron paramagnetic resonance EPR measurements were carried out

  8. High contrast, CdTe portal scanner for radiation therapy

    SciTech Connect (OSTI)

    Entine, G.; Squillante, M.R.; Hahn, R.; Cirignano, L.J.; McGann, W. (Radiation Monitoring Devices, Inc., Watertown, MA (United States)); Biggs, P.J. (Massachusetts General Hospital, Boston, MA (United States))

    1992-10-01T23:59:59.000Z

    This paper reports on one of the most promising new technologies for improving the qualify of radiation therapy, the use of real-time systems to produce portal images. In the authors' approach, they are constructing a linear array of 256 CdTe photovoltaic detectors attached to a very compact linear scanner, all of which will be mounted in a cassette shaped package to be located under the patient table. The high stopping power of the CdTe allows a high contrast image to be made using only a single Linac pulse per line, resulting in a high contrast image in under 5 seconds.

  9. Impaired NFAT and NF?B activation are involved in suppression of CD40 ligand expression by ?{sup 9}-tetrahydrocannabinol in human CD4{sup +} T cells

    SciTech Connect (OSTI)

    Ngaotepprutaram, Thitirat [Department of Pharmacology and Toxicology, Michigan State University (United States); Center for Integrative Toxicology, Michigan State University (United States); Kaplan, Barbara L.F. [Department of Pharmacology and Toxicology, Michigan State University (United States); Center for Integrative Toxicology, Michigan State University (United States); Neuroscience Program, Michigan State University (United States); Kaminski, Norbert E., E-mail: kamins11@msu.edu [Department of Pharmacology and Toxicology, Michigan State University (United States); Center for Integrative Toxicology, Michigan State University (United States)

    2013-11-15T23:59:59.000Z

    We have previously reported that ?{sup 9}-tetrahydrocannabinol (?{sup 9}-THC), the main psychoactive cannabinoid in marijuana, suppresses CD40 ligand (CD40L) expression by activated mouse CD4{sup +} T cells. CD40L is involved in pathogenesis of many autoimmune and inflammatory diseases. In the present study, we investigated the molecular mechanism of ?{sup 9}-THC-mediated suppression of CD40L expression using peripheral blood human T cells. Pretreatment with ?{sup 9}-THC attenuated CD40L expression in human CD4{sup +} T cells activated by anti-CD3/CD28 at both the protein and mRNA level, as determined by flow cytometry and quantitative real-time PCR, respectively. Electrophoretic mobility shift assays revealed that ?{sup 9}-THC suppressed the DNA-binding activity of both NFAT and NF?B to their respective response elements within the CD40L promoter. An assessment of the effect of ?{sup 9}-THC on proximal T cell-receptor (TCR) signaling induced by anti-CD3/CD28 showed significant impairment in the rise of intracellular calcium, but no significant effect on the phosphorylation of ZAP70, PLC?1/2, Akt, and GSK3?. Collectively, these findings identify perturbation of the calcium-NFAT and NF?B signaling cascade as a key mechanistic event by which ?{sup 9}-THC suppresses human T cell function. - Highlights: • ?{sup 9}-THC attenuated CD40L expression in activated human CD4+ T cells. • ?{sup 9}-THC suppressed DNA-binding activity of NFAT and NF?B. • ?{sup 9}-THC impaired elevation of intracellular Ca2+. • ?{sup 9}-THC did not affect phosphorylation of ZAP70, PLC?1/2, Akt, and GSK3?.

  10. Magnetism in undoped ZnS studied from density functional theory

    SciTech Connect (OSTI)

    Xiao, Wen-Zhi, E-mail: xiaowenzhi@hnu.edu.cn, E-mail: llwang@hun.edu.cn; Rong, Qing-Yan; Xiao, Gang [Department of Physics and Mathematics, Hunan Institute of Engineering, Xiangtan 411104 (China); Wang, Ling-ling, E-mail: xiaowenzhi@hnu.edu.cn, E-mail: llwang@hun.edu.cn [School of Physics and Microelectronics and Key Lab for Micro-Nano Physics and Technology of Hunan Province, Hunan University, Changsha 410082 (China); Meng, Bo [College of Physics and Electronic Engineering, Caili University, Kaili 556011 (China)

    2014-06-07T23:59:59.000Z

    The magnetic property induced by the native defects in ZnS bulk, thin film, and quantum dots are investigated comprehensively based on density functional theory within the generalized gradient approximation + Hubbard U (GGA?+?U) approach. We find the origin of magnetism is closely related to the introduction of hole into ZnS systems. The relative localization of S-3p orbitals is another key to resulting in unpaired p-electron, due to Hund's rule. For almost all the ZnS systems under study, the magnetic moment arises from the S-dangling bonds generated by Zn vacancies. The charge-neutral Zn vacancy, Zn vacancy in 1? charge sate, and S vacancy in the 1+ charge sate produce a local magnetic moment of 2.0, 1.0, and 1.0??{sub B}, respectively. The Zn vacancy in the neutral and 1? charge sates are the important cause for the ferromagnetism in ZnS bulk, with a Curie temperature (T{sub C}) above room temperature. For ZnS thin film with clean (111) surfaces, the spins on each surface are ferromagnetically coupled but antiferromagnetically coupled between two surfaces, which is attributable to the internal electric field between the two polar (111) surfaces of the thin film. Only surface Zn vacancies can yield local magnetic moment for ZnS thin film and quantum dot, which is ascribed to the surface effect. Interactions between magnetic moments on S-3p states induced by hole-doping are responsible for the ferromagnetism observed experimentally in various ZnS samples.

  11. Supporting information for: Na-doped p-type ZnO , Faxian Xiu2

    E-Print Network [OSTI]

    Yang, Zheng

    S1 Supporting information for: Na-doped p-type ZnO microwires Wei Liu1* , Faxian Xiu2 , Ke Sun1 flow was switched to argon followed by cooling to room temperature. After the growth, high-density Zn distribution of the Na Doped ZnO microwire 1.3 EDX line scans spectra #12;S3 Figure S3 a) a typical TEM image

  12. Co-adapted coupling Random walk on Zn 2 Random walk on Gn

    E-Print Network [OSTI]

    Co-adapted coupling Random walk on Zn 2 Random walk on Gn d Optimal co-adapted coupling Stephen Connor sbc502@york.ac.uk #12;Co-adapted coupling Random walk on Zn 2 Random walk on Gn d Outline 1 Co-adapted coupling 2 Simple random walk on the hypercube, Zn 2 3 Simple random walk on Gn d #12;Co-adapted coupling

  13. Narrow Bandgap in beta-BaZn2As2 and Its Chemical Origins

    E-Print Network [OSTI]

    Xiao, Zewen; Ueda, Shigenori; Toda, Yoshitake; Ran, Fan-Yong; Guo, Jiangang; Lei, Hechang; Matsuishi, Satoru; Hosono, Hideo; Kamiya, Toshio

    2015-01-01T23:59:59.000Z

    Beta-BaZn2As2 is known to be a p-type semiconductor with the layered crystal structure similar to that of LaZnAsO, leading to the expectation that beta-BaZn2As2 and LaZnAsO have similar bandgaps; however, the bandgap of beta-BaZn2As2 (previously-reported value ~0.2 eV) is one order of magnitude smaller than that of LaZnAsO (1.5 eV). In this paper, the reliable bandgap value of beta-BaZn2As2 is determined to be 0.23 eV from the intrinsic region of the tem-perature dependence of electrical conductivity. The origins of this narrow bandgap are discussed based on the chemi-cal bonding nature probed by 6 keV hard X-ray photoemission spectroscopy, hybrid density functional calculations, and the ligand theory. One origin is the direct As-As hybridization between adjacent [ZnAs] layers, which leads to a secondary splitting of As 4p levels and raises the valence band maximum. The other is that the non-bonding Ba 5dx2-y2 orbitals form unexpectedly deep conduction band minimum (CBM) in beta-BaZn2As2 although the CBM of L...

  14. Optical and morphological properties of graphene sheets decorated with ZnO nanowires via polyol enhancement

    SciTech Connect (OSTI)

    Sharma, Vinay, E-mail: winn201@gmail.com; Rajaura, Rajveer Singh, E-mail: winn201@gmail.com [Centre for Converging Technologies, University of Rajasthan, Jaipur - 302004 (India); Sharma, Preetam K.; Srivastava, Subodh; Vijay, Y. K. [Department of Physics, Thin Film and Membrane Science Lab., University of Rajasthan, Jaipur - 302004 (India); Sharma, S. S. [Department of Physics, Govt. Women Engineering College, Ajmer- 305002 (India)

    2014-04-24T23:59:59.000Z

    Graphene-ZnO nanocomposites have proven to be very useful materials for photovoltaic and sensor applications. Here, we report a facile, one-step in situ polymerization method for synthesis of graphene sheets randomly decorated with zinc oxide nanowires using ethylene glycol as solvent. We have used hydrothermal treatment for growth of ZnO nanowires. UV-visible spectra peak shifting around 288nm and 307 nm shows the presence of ZnO on graphene structure. Photoluminiscence spectra (PL) in 400nm-500nm region exhibits the luminescence quenching effect. Scanning electron microscopy (SEM) image confirms the growth of ZnO nanowires on graphene sheets.

  15. Hidden Ferromagnetic Secondary Phases in Cobalt-doped ZnO Epitaxial...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ZnO Epitaxial Thin Films. Abstract: The quest to discover a dilute magnetic semiconductor which is ferromagnetic at room temperature has led to extensive research on...

  16. Structure of {sup 81}Ga populated from the {beta}{sup -} decay of {sup 81}Zn

    SciTech Connect (OSTI)

    Paziy, V.; Mach, H.; Fraile, L. M.; Olaizola, B.; Udias, J. M. [Grupo de Fisica Nuclear, Universidad Complutense, Madrid (Spain); Aprahamian, A.; Bucher, B. [Department of Physics, University of Notre Dame (United States); Bernards, C. [Institut fuer Kernphysik, Koeln, Germany. and Wright Nuclear Structure Laboratory, Yale University, New Haven, CT-06520 (United States); Briz, J. A. [Instituto de Estructura de la Materia, CSIC, Madrid (Spain); Chiara, C. J. [Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland, USA. and Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Dlouhy, Z. [Nuclear Physics Institute of the ASCR, Rez (Czech Republic); Gheorghe, I.; Ghita, D.; Lica, R.; Marginean, N.; Marginean, R.; Stanoiu, M.; Stroe, L. [National Institute for Physics and Nuclear Engineering, Magurele (Romania); Hoff, P. [Department of Chemistry, University of Oslo, Oslo (Norway); Koester, U. [Institut Laue Langevin, 6 Rue Jules Horowitz, F-38042 Grenoble Cedex 9 (France); and others

    2013-06-10T23:59:59.000Z

    We report on the results of the {beta}-decay of {sup 81}Zn. The experiment was performed at the CERN ISOLDE facility in the framework of a systematic ultra-fast timing investigation of neutron-rich nuclei populated in the decay of Zn. The present analysis included {beta}-gated {gamma}-ray singles and {gamma}-{gamma} coincidences from the decay of {sup 81}Zn to {sup 81}Ga and leads to a new and much more extensive level scheme of {sup 81}Ga. A new half-life of {sup 81}Zn is provided.

  17. Green synthesis of graphene nanosheets/ZnO composites and electrochemical properties

    SciTech Connect (OSTI)

    Wang Jun, E-mail: zhqw1888@sohu.com [College of Material Science and Chemical Engineering, Harbin Engineering University, Harbin 150001 (China); Key Laboratory of Superlight Materials and Surface Technology, Ministry of Education, Harbin 150001 (China); Gao Zan [College of Material Science and Chemical Engineering, Harbin Engineering University, Harbin 150001 (China); Key Laboratory of Superlight Materials and Surface Technology, Ministry of Education, Harbin 150001 (China); Li Zhanshuang; Wang Bin; Yan Yanxia; Liu Qi [College of Material Science and Chemical Engineering, Harbin Engineering University, Harbin 150001 (China); Mann, Tom [Key Laboratory of Superlight Materials and Surface Technology, Ministry of Education, Harbin 150001 (China); Zhang Milin [College of Material Science and Chemical Engineering, Harbin Engineering University, Harbin 150001 (China); Key Laboratory of Superlight Materials and Surface Technology, Ministry of Education, Harbin 150001 (China); Jiang Zhaohua [College of Chemical Engineering, Harbin Institute of Technology, Harbin 150001 (China)

    2011-06-15T23:59:59.000Z

    A green and facile approach was demonstrated to prepare graphene nanosheets/ZnO (GNS/ZnO) composites for supercapacitor materials. Glucose, as a reducing agent, and exfoliated graphite oxide (GO), as precursor, were used to synthesize GNS, then ZnO directly grew onto conducting graphene nanosheets as electrode materials. The small ZnO particles successfully anchored onto graphene sheets as spacers to keep the neighboring sheets separate. The electrochemical performances of these electrodes were analyzed by cyclic voltammetry, electrochemical impedance spectrometry and chronopotentiometry. Results showed that the GNS/ZnO composites displayed superior capacitive performance with large capacitance (62.2 F/g), excellent cyclic performance, and maximum power density (8.1 kW/kg) as compared with pure graphene electrodes. Our investigation highlight the importance of anchoring of small ZnO particles on graphene sheets for maximum utilization of electrochemically active ZnO and graphene for energy storage application in supercapacitors. - Graphical abstract: Glucose was used to synthesize GNS, then ZnO directly grew onto conducting graphene nanosheets as electrode materials for supercapacitor. Results showed that the composites have superior capacitive performance. Highlights: > Graphene nanosheets were synthesized via using glucose as a reducing agent. > The reductant and the oxidized product are environmentally friendly. > ZnO grew onto conducting graphene sheets keeping neighboring sheets separate. > The structure improves the contact between the electrode and the electrolyte. > Results showed that these composites have good electrochemical property.

  18. Phase diagram, crystal chemistry and thermoelectric properties of compounds in the Ca?Co?Zn?O system

    SciTech Connect (OSTI)

    Wong-Ng, W.; Luo, T.; Xie, W.; Tang, W.H.; Kaduk, J.A.; Huang, Q.; Yan, Y.; Chattopadhyay, S.; Tang, X.; Tritt, T. (IIT); (Clemson); (NIST); (Maryland); (Zhejiang); (Wuhan)

    2011-11-17T23:59:59.000Z

    In the Ca-Co-Zn-O system, we have determined the tie-line relationships and the thermoelectric properties, solid solution limits, and structures of two low-dimensional cobaltite series, Ca{sub 3}(Co, Zn){sub 4}O{sub 9-z} and Ca{sub 3}(Co,Zn){sub 2}O{sub 6-z} at 885 C in air. In Ca{sub 3}(Co,Zn){sub 4}O{sub 9-z}, which has a misfit layered structure, Zn was found to substitute in the Co site to a limit of Ca{sub 3}(Co{sub 3.8}Zn{sub 0.2})O{sub 9-z}. The compound Ca{sub 3}(Co,Zn){sub 2}O{sub 6-z} (n=1 member of the homologous series, Ca{sub n+2}(Co,Zn)n(Co,Zn)'O{sub 3n+3-z}) consists of one-dimensional parallel (Co,Zn){sub 2}O{sub 6}{sup 6-} chains that are built from successive alternating face-sharing (Co,Zn)O{sub 6} trigonal prisms and 'n' units of (Co,Zn)O{sub 6} octahedra along the hexagonal c-axis. Zn substitutes in the Co site of Ca{sub 3}Co{sub 2}O{sub 6} to a small amount of approximately Ca{sub 3}(Co{sub 1.95}Zn{sub 0.05})O{sub 6-z}. In the ZnO-CoO{sub z} system, Zn substitutes in the tetrahedral Co site of Co{sub 3}O{sub 4} to the maximum amount of (Co{sub 2.49}Zn{sub 0.51})O{sub 4-z} and Co substitutes in the Zn site of ZnO to (Zn{sub 0.94}Co{sub 0.06})O. The crystal structures of (Co{sub 2.7}Zn{sub 0.3})O{sub 4-z}, (Zn{sub 0.94}Co{sub 0.06})O, and Ca{sub 3}(Co{sub 1.95} Zn{sub 0.05})O{sub 6-z} are described. Despite the Ca{sub 3}(Co, Zn){sub 2}O{sub 6-z} series having reasonably high Seebeck coefficients and relatively low thermal conductivity, the electrical resistivity values of its members are too high to achieve high figure of merit, ZT.

  19. Strain-Dependent Photoluminescence Behavior of CdSe/CdS Nanocrystals with Spherical, Linear, and Branched Topologies

    SciTech Connect (OSTI)

    Choi, Charina L.; Koski, Kristie J.; Sivasankar, Sanjeevi; Alivisatos, A. Paul

    2009-08-13T23:59:59.000Z

    The photoluminescence of CdSe/CdS core/shell quantum dots, nanorods, and tetrapods is investigated as a function of applied hydrostatic and non-hydrostatic pressure. The optoelectronic properties of all three nanocrystal morphologies are affected by strain. Furthermore, it is demonstrated that the unique morphology of a tetrapod is highly sensitive to non-isotropic stress environments. Seeded tetrapods can thereby serve as an optical strain gauge, capable of measuring forces on the order of nanonewtons. We anticipate that a nanocrystal strain gauge with optical readout will be useful for applications ranging from sensitive optomechanical devices to investigations of biomechanical processes.

  20. Visualization of Peroxynitrite-Induced Changes of Labile Zn[superscript 2+] in the Endoplasmic Reticulum with Benzoresorufin-based Fluorescent Probes

    E-Print Network [OSTI]

    Lin, Wei

    Zn[superscript 2+] plays essential roles in biology, and the homeostasis of Zn[superscript 2+] is tightly regulated in all cells. Subcellular distribution and trafficking of labile Zn[superscript 2+], and its inter-relation ...

  1. Zinc Fertilization Plus Liming to Reduce Cadmium Uptake by Romaine Lettuce on Cd-Mineralized Lockwood Soil

    E-Print Network [OSTI]

    Chaney, Rufus L; Green, Carrie E.; Ajwa, Husein A; Smith, Richard F

    2009-01-01T23:59:59.000Z

    Cd accumulation by lettuce from biosolids amended soils withmine waste contaminated or biosolids-amended soils with Cd:of a highly Cd enriched biosolids also found that liming

  2. Factors important for the establishment and maintenance of HIV-1 latency in CD4 T cells

    E-Print Network [OSTI]

    Soto, Paula Campos

    2008-01-01T23:59:59.000Z

    the Establishment and Maintenance of HIV-1 Latency in CD4 TFunction, generation, and maintenance. Annu Rev Immunol. 19.the Establishment and Maintenance of HIV-1 Latency in CD4 T

  3. Geochemical associations and availability of cadmium (Cd) in a paddy field system, Northwestern Thailand 

    E-Print Network [OSTI]

    Kosolsaksakul, Peerapat

    2014-11-27T23:59:59.000Z

    The Mae Tao watershed, northwestern Thailand, has become contaminated with cadmium (Cd) from the zinc mining activities area in the nearby Thanon-Thongchai mountains. Consumption of Cd-contaminated rice has led to ...

  4. THE ROLE OF ADAPTOR PROTEIN GADS IN CD8+ T CELL-MEDIATED IMMUNITY

    E-Print Network [OSTI]

    Zhang, Elizabeth Yan

    2011-12-31T23:59:59.000Z

    CD8+ T cells are the branch of the adaptive immune system responsible for recognizing and killing tumor cells or cells infected with intracellular pathogens, such as Listeria monocytogenes (LM). However, when CD8+ T cells ...

  5. Thin Metal Oxide Films to Modify a Window Layer in CdTe-Based...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Thin Metal Oxide Films to Modify a Window Layer in CdTe-Based Solar Cells for Improved Performance. Thin Metal Oxide Films to Modify a Window Layer in CdTe-Based Solar Cells for...

  6. CD4CDM Developments Romeo Pacudan PhD

    E-Print Network [OSTI]

    : Egypt, Morocco · SS Africa: Côte d'Ivoire, Mozambique, Uganda #12;1. CD4CDM project background Project. MICOA (Mozambique) 3. DMET (Uganda) 1. TIMS (Egypt) 2. SSE (Morocco) 1. ODL (Bolivia) 2. Cordelim Groups (TWG) Representatives of MoE, MAFF, MIME, MoP, CDC, MPWT Energy TWG Forestry TWG Others (if

  7. Microfluidics for biological analysis: Triumphs and hurdles of CD platforms

    E-Print Network [OSTI]

    Joshi, Yogesh Moreshwar

    Microfluidics for biological analysis: Triumphs and hurdles of CD platforms JONATHAN SIEGRIST1 , R on microfluidic technologies has become extensive, particularly in regards to the develop- ment of sample. Centrifugal microfluidic platforms based on the compact-disc format are discussed, along with the advantages

  8. CdWO4 crystal scintillators from enriched isotopes for double beta decay experiments

    E-Print Network [OSTI]

    D. V. Poda; A. S. Barabash; P. Belli; R. Bernabei; R. S. Boiko; V. B. Brudanin; F. Cappella; V. Caracciolo; S. Castellano; R. Cerulli; D. M. Chernyak; F. A. Danevich; S. d'Angelo; V. Ya. Degoda; M. L. Di Vacri; A. E. Dossovitskiy; E. N. Galashov; A. Incicchitti; V. V. Kobychev; S. I. Konovalov; G. P. Kovtun; M. Laubenstein; A. L. Mikhlin; V. M. Mokina; A. S. Nikolaiko; S. Nisi; R. B. Podviyanuk; O. G. Polischuk; A. P. Shcherban; V. N. Shlegel; D. A. Solopikhin; V. I. Tretyak; V. I. Umatov; Ya. V. Vasiliev; V. D. Virich

    2013-02-20T23:59:59.000Z

    Cadmium tungstate crystal scintillators enriched in 106Cd and 116Cd were developed. The produced scintillators exhibit good optical and scintillation properties, and a low level of radioactive contamination. Experiments to search for double beta decay of 106Cd and 116Cd are in progress at the Gran Sasso National Laboratories of the INFN (Italy). Prospects to further improve the radiopurity of the detectors by recrystallization are discussed.

  9. CdWO4 crystal scintillators from enriched isotopes for double beta decay experiments

    E-Print Network [OSTI]

    Poda, D V; Belli, P; Bernabei, R; Boiko, R S; Brudanin, V B; Cappella, F; Caracciolo, V; Castellano, S; Cerulli, R; Chernyak, D M; Danevich, F A; d'Angelo, S; Degoda, V Ya; Di Vacri, M L; Dossovitskiy, A E; Galashov, E N; Incicchitti, A; Kobychev, V V; Konovalov, S I; Kovtun, G P; Laubenstein, M; Mikhlin, A L; Mokina, V M; Nikolaiko, A S; Nisi, S; Podviyanuk, R B; Polischuk, O G; Shcherban, A P; Shlegel, V N; Solopikhin, D A; Tretyak, V I; Umatov, V I; Vasiliev, Ya V; Virich, V D

    2013-01-01T23:59:59.000Z

    Cadmium tungstate crystal scintillators enriched in 106Cd and 116Cd were developed. The produced scintillators exhibit good optical and scintillation properties, and a low level of radioactive contamination. Experiments to search for double beta decay of 106Cd and 116Cd are in progress at the Gran Sasso National Laboratories of the INFN (Italy). Prospects to further improve the radiopurity of the detectors by recrystallization are discussed.

  10. Structural Stability and Defect Energetics of ZnO from Diffusion Quantum Monte Carlo

    SciTech Connect (OSTI)

    Santana Palacio, Juan A [ORNL; Krogel, Jaron T [ORNL; Kim, Jeongnim [ORNL; Kent, Paul R [ORNL; Reboredo, Fernando A [ORNL

    2015-01-01T23:59:59.000Z

    We have applied the many-body ab-initio diffusion quantum Monte Carlo (DMC) method to study Zn and ZnO crystals under pressure, and the energetics of the oxygen vacancy, zinc interstitial and hydrogen impurities in ZnO. We show that DMC is an accurate and practical method that can be used to characterize multiple properties of materials that are challenging for density functional theory approximations. DMC agrees with experimental measurements to within 0.3 eV, including the band-gap of ZnO, the ionization potential of O and Zn, and the atomization energy of O2, ZnO dimer, and wurtzite ZnO. DMC predicts the oxygen vacancy as a deep donor with a formation energy of 5.0(2) eV under O-rich conditions and thermodynamic transition levels located between 1.8 and 2.5 eV from the valence band maximum. Our DMC results indicate that the concentration of zinc interstitial and hydrogen impurities in ZnO should be low under n-type, and Zn- and H-rich conditions because these defects have formation energies above 1.4 eV under these conditions. Comparison of DMC and hybrid functionals shows that these DFT approximations can be parameterized to yield a general correct qualitative description of ZnO. However, the formation energy of defects in ZnO evaluated with DMC and hybrid functionals can differ by more than 0.5 eV.

  11. Mechanisms of the Wurtzite to Rocksalt Transformation in CdSe Nanocrystals Michael Grunwald,1

    E-Print Network [OSTI]

    Rabani, Eran

    Mechanisms of the Wurtzite to Rocksalt Transformation in CdSe Nanocrystals Michael Gru¨nwald,1 Eran transition from the four-coordinate wurtzite to the six-coordinate rocksalt structure in CdSe nanocrystals wurtzite structure to the six-coordinate rocksalt structure in CdSe is strongly influenced by crystal size

  12. Solar Energy Materials & Solar Cells 91 (2007) 13881391 Bifacial configurations for CdTe solar cells

    E-Print Network [OSTI]

    Romeo, Alessandro

    2007-01-01T23:59:59.000Z

    Solar Energy Materials & Solar Cells 91 (2007) 1388­1391 Bifacial configurations for CdTe solar We present a different back contact for CdTe solar cell by the application of only a transparent that acts as a free-Cu stable back contact and at the same time allows to realize bifacial CdTe solar cells

  13. USING CORIOLIS FORCE TO FACILITATE MOLECULAR TRANSPORTATION AND FLUID MIXING IN CD MICROFLUIDICS

    E-Print Network [OSTI]

    Kassegne, Samuel Kinde

    e. USING CORIOLIS FORCE TO FACILITATE MOLECULAR TRANSPORTATION AND FLUID MIXING IN CD MICROFLUIDICS Coriolis Force to Facilitate Molecular Transportation and Fluid Mixing in CD Microfluidics Platform and Fluid mixing in compact disk (CD) microfluidic platform where centrifugal force is used as the driving

  14. DISSERTATION ELECTRON-REFLECTOR STRATEGY FOR CdTe THIN-FILM SOLAR CELLS

    E-Print Network [OSTI]

    Sites, James R.

    DISSERTATION ELECTRON-REFLECTOR STRATEGY FOR CdTe THIN-FILM SOLAR CELLS Submitted by Kuo-Jui Hsiao ELECTRON- REFLECTOR STRATEGY FOR CdTe THIN-FILM SOLAR CELLS BE ACCEPTED AS FULFILLING IN PART REQUIREMENTS-FILM SOLAR CELLS The CdTe thin-film solar cell has a large absorption coefficient and high theoretical

  15. Surface chemistry controls crystallinity of ZnSnanoparticles

    SciTech Connect (OSTI)

    Gilbert, Benjamin; Huang, Feng; Lin, Zhang; Goodell, Carmen; Zhang, Hengzhong; Banfield Jillian F.

    2005-12-20T23:59:59.000Z

    Combined small-angle and high energy wide-angle x-ray scattering measurements of nanoparticle size and structure permit interior strain and disorder to be directly observed in the real-space pair distribution function (PDF). PDF analysis showed that samples of ZnS nanoparticle with similar mean diameters (3.2-3.6 nm) but synthesized and treated differently possess a dramatic range of interior disorder. We used Fourier transform infra-red spectroscopy to detect the surface species and the nature of surface chemical interactions. Our results suggest that there is a direct correlation between the strength of surface-ligand interactions and interior crystallinity.

  16. Structural Phase Transition in AuZn Alloys

    SciTech Connect (OSTI)

    Winn,B.L.; Shapiro, S.M.; Lashley, J.C.; Opeil, C.; Ratcliff, W.

    2009-05-03T23:59:59.000Z

    AuxZn1-x alloys undergo a shape memory martensitic transformation whose temperature and nature (continuous or discontinuous) is strongly composition dependent. Neutron diffraction experiments were performed on single crystals of x=50 and 52 to explore the structural changes occurring at the transition temperature. A transverse modulation with wavevector q0=(1/3,1/3,0) develops below the transition temperature, with no observable change in lattice parameter. However, the Bragg peak width shows a broadening suggesting an unresolved rhombohedral distortion similar to what has been observed in NiTi-Fe alloys.

  17. Diamond-machined ZnSe immersion grating for NIR high-resolution spectroscopy

    SciTech Connect (OSTI)

    Ikeda, Y; Kobayashi, N; Kuzmenko, P J; Little, S L; Yasui, C; Kondo, S; Minami, A; Motohara, K

    2008-07-25T23:59:59.000Z

    ZnSe immersion gratings (n {approx} 2.45) provide the possibility of high-resolution spectroscopy for the near-infrared (NIR) region. Since ZnSe has a lower internal attenuation than other NIR materials, it is most suitable for immersion grating, particularly in short NIR region (0.8-1.4 {micro}m). We are developing an extremely high-resolution spectrograph with {lambda}/{Delta}{lambda} = 100,000, WINERED, customized for the short NIR region, using ZnSe (or ZnS) immersion grating. However, it had been very difficult to make fine grooves on ZnSe substrate with a small pitch of less than 50 {micro}m because ZnSe is a soft/brittle material. We have overcome this problem and successfully machined sharp grooves with fine pitch on ZnSe substrates by nano precision fly-cutting technique at LLNL. The optical testing of the sample grating with HeNe laser shows an excellent performance: the relative efficiency more than 87.4 % at 0.633 {micro}m for a classical grating configuration. The diffraction efficiency when used as an immersion grating is estimated to be more than 65 % at 1 {micro}m. Following this progress, we are about to start machining a grating on a large ZnSe prism with an entrance aperture of 23mm x 50mm and the blaze angle of 70{sup o}.

  18. Thickness influence on surface morphology and ozone sensing properties of nanostructured ZnO transparent

    E-Print Network [OSTI]

    , 71004 Heraklion, Crete, Greece Available online 19 January 2006 Abstract Transparent zinc oxide (Zn Keywords: Zinc oxide; PLD; AFM; Ozone 1. Introduction Zinc oxide (ZnO) is an n-type semiconductor devices [3], varistors, planar optical waveguides [4], transparent electrodes [5,6], ultraviolet

  19. DOI: 10.1002/adma.200702781 Aerogel Templated ZnO Dye-Sensitized Solar Cells**

    E-Print Network [OSTI]

    as substructure templates. The aerogel templates are coated with ZnO via atomic layer deposition (ALD) to yieldDOI: 10.1002/adma.200702781 Aerogel Templated ZnO Dye-Sensitized Solar Cells** By Thomas W. Hamann produced from coating tem- plates of high aspect ratio substructures, exhibiting initial efficiencies up

  20. Growth of anisotropic one-dimensional ZnS nanostructures{ Daniel Moore and Zhong L. Wang*

    E-Print Network [OSTI]

    Wang, Zhong L.

    with wurtzite ZnS. This feature article covers the ZnS one-dimensional nanostructures that have been synthesized crystal structure known as the wurtzite structure (Fig. 1). This transformation has been shown to occur at 1020 uC. The zinc blend and wurtzite structures are very similar. The stacking sequence of the close

  1. ClebschGordan coefficients for scattering tensors in ZnO and other

    E-Print Network [OSTI]

    Nabben, Reinhard

    Clebsch­Gordan coefficients for scattering tensors in ZnO and other wurtzite semiconductors Herbert, and A are investigated in wurtzite ZnO. The knowledge of the selection rules is required for the determination, in non-centro-symmetric crystals (zinc blende and wurtzite) the strain tensor and induced electric fields

  2. Relative stability of nanosized wurtzite and graphitic ZnO from density functional theory

    E-Print Network [OSTI]

    Melnik, Roderick

    Relative stability of nanosized wurtzite and graphitic ZnO from density functional theory Bin Wen to determine the relative stability of wurtzite and graphitic phases of ZnO nanostructures. Our results the threshold number, the relative stability of the wurtzite phase is observed. Finally, we discuss

  3. Reduction of the transverse effective charge of optical phonons in ZnO under pressure

    E-Print Network [OSTI]

    Nabben, Reinhard

    ; accepted 18 May 2010; published online 9 June 2010 From Raman scattering on a-plane wurtzite ZnO crystalsO is the wurtzite structure. Recently, the me- chanical properties of ZnO have been investigated up to 60 GPa.4 The initial wurtzite phase was observed to transform to the rocksalt structure around 9.1 GPa with a large

  4. Zinc-blende ZnO and its role in nucleating wurtzite tetrapods and twinned nanowires

    E-Print Network [OSTI]

    Wang, Zhong L.

    Zinc-blende ZnO and its role in nucleating wurtzite tetrapods and twinned nanowires Yong Ding of wurtzite WZ ZnO tetrapods. The formation of the wurtzite 011¯3 twined nanowires is proposed based on the ZB core. Simple bonding density calculation shows that the wurtzite nanowires with 011¯0 side surfaces

  5. Wurtzite ZnS nanosaws produced by polar surfaces Daniel Moore a

    E-Print Network [OSTI]

    Wang, Zhong L.

    Wurtzite ZnS nanosaws produced by polar surfaces Daniel Moore a , Carsten Ronning a,b , Christopher December 2003 Published online: 10 January 2004 Abstract Wurtzite structured ZnS nanoribbons have been for electronic and optoelectronic nanodevices [12,13]. Zinc blend and wurtzite structures are the two most

  6. Water adsorption on stepped ZnO surfaces from MD simulation David Raymand a

    E-Print Network [OSTI]

    Goddard III, William A.

    Water adsorption on stepped ZnO surfaces from MD simulation David Raymand a , Adri C.T. van Duin b Keywords: Zinc oxide Water Solid­gas interfaces Construction and use of effective interatomic interactions force-field for use in molecular dynamics simulations of the ZnO­ water system. The force

  7. Structure and magnetic properties of rf thermally plasma synthesized Mn and MnZn ferrite nanoparticles

    E-Print Network [OSTI]

    McHenry, Michael E.

    Structure and magnetic properties of rf thermally plasma synthesized Mn and Mn­Zn ferrite has previously been shown to be a viable route to producing nanocrystalline magnetite and Ni ferrite nanoparticles. In this work nanocrystalline powders of Mn and Mn­Zn ferrites have been synthesized using a 50 k

  8. An Analysis of Mn-Zn Ferrite Microstructure by Impedance Spectroscopy, STEM and EDS Characterisations.

    E-Print Network [OSTI]

    Boyer, Edmond

    An Analysis of Mn-Zn Ferrite Microstructure by Impedance Spectroscopy, STEM and EDS.loyau@satie.ens-cachan.fr Abstract AC resistivity measurement results on Mn-Zn sintered ferrite were analyzed in the 0.1-500 MHz of the main limitations in frequency increase is the energy dissipations by losses in ferrites that produce

  9. Microstructural Evolution Model of the Sintering Behavior and Magnetic Properties of NiZn Ferrite Nanoparticles

    E-Print Network [OSTI]

    McHenry, Michael E.

    Microstructural Evolution Model of the Sintering Behavior and Magnetic Properties of NiZn Ferrite jlwoods@andrew.cmu.edu, c SCalvin@slc.edu, d jhuth@Spang.co, e mm7g@andrew.cmu.edu Keywords: Ferrite, nanoparticle, sintering, microstructure. Abstract. The sintering of RF plasma synthesized NiZn ferrite

  10. THE LIND-LEHMER CONSTANT FOR Zn DILUM DESILVA AND CHRISTOPHER PINNER

    E-Print Network [OSTI]

    Pinner, Christopher

    THE LIND-LEHMER CONSTANT FOR Zn p DILUM DESILVA AND CHRISTOPHER PINNER Abstract. We determine the Lind Lehmer constant for groups of the form Zn p . 1. Introduction Let G be a compact abelian group of integral combinations of characters, Lind [6] defines a logarithmic Mahler measure of f over G m(f) = m

  11. Fabrication of Microfibre-nanowire Junction Arrays of ZnO/SnO2 Composite

    E-Print Network [OSTI]

    Iglic, Ales

    nanocomposite sensitized with a D35-cpdt dye was investigated. A dye-sensitized solar cell (DSSC) with a Zn discussed. Keywords ZnO/SnO2 Nanocomposite, Dye-sensitized Solar Cell, Nanostructured Surfaces 1O/SnO2 nanocomposite photoanode based on a cobalt electrolyte achieved a solar-to-electricity conversion

  12. DOI: 10.1002/adfm.200701073 Polydisperse Aggregates of ZnO Nanocrystallites: A Method

    E-Print Network [OSTI]

    Cao, Guozhong

    -Conversion-Efficiency Enhancement in Dye-Sensitized Solar Cells** By Qifeng Zhang, Tammy P. Chou, Bryan Russo, Samson A. Jenekhe, and Guozhong Cao* 1. Introduction ZnO-based dye-sensitized solar cells (DSSCs) have attrac- ted considerable a relatively efficient dye-sensitized ZnO solar cell with a conversion efficiency of $3

  13. Effect of Zinc (Zn (II)) on the Adsorption Mechanisms of Arsenate (As (V)) at the

    E-Print Network [OSTI]

    Sparks, Donald L.

    Effect of Zinc (Zn (II)) on the Adsorption Mechanisms of Arsenate (As (V)) at the Goethite of As and Zn adsorption on goethite was investigated over a pH range of 3 to 10. X-ray absorption fine adsorption on goethite. The macroscopic data show that As adsorption on goethite was envelope

  14. Improvement of electroluminescence performance by integration of ZnO nanowires and single-crystalline films on ZnO/GaN heterojunction

    SciTech Connect (OSTI)

    Shi, Zhifeng; Zhang, Yuantao, E-mail: zhangyt@jlu.edu.cn; Cui, Xijun; Wu, Bin; Zhuang, Shiwei; Yang, Fan; Zhang, Baolin; Du, Guotong [State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Qianjin Street 2699, Changchun 130012 (China); Yang, Xiaotian [School of Electrical and Electronic Information, Jilin Institute of Architecture and Civil Engineering, Changchun 130118 (China)

    2014-03-31T23:59:59.000Z

    Heterojunction light-emitting diodes based on n-ZnO nanowires/ZnO single-crystalline films/p-GaN structure have been demonstrated for an improved electroluminescence performance. A highly efficient ultraviolet emission was observed under forward bias. Compared with conventional n-ZnO/p-GaN structure, high internal quantum efficiency and light extraction efficiency were simultaneously considered in the proposed diode. In addition, the diode can work continuously for ?10?h with only a slight degradation in harsh environments, indicating its good reliability and application prospect in the future. This route opens possibilities for the development of advanced nanoscale devices in which the advantages of ZnO single-crystalline films and nanostructures can be integrated together.

  15. X-ray diffraction study of thermal stress relaxation in ZnO films deposited by magnetron sputtering

    E-Print Network [OSTI]

    silicon substrate: ZnO and ZnO encapsulated into Si3N4 layers. We showed that both as-deposited ZnO films with Si3N4 encapsulation. The observations show that Si3N4 films lying on both sides of the ZnO film play in many application domains such as ultraviolet detectors, light-emitting diodes, solar cells. As a II

  16. SrAgZn and EuAgZn with KHg{sub 2}-type structure—Structure, magnetic properties, and {sup 151}Eu Mössbauer spectroscopy

    SciTech Connect (OSTI)

    Gerke, Birgit; Rodewald, Ute Ch.; Niehaus, Oliver; Pöttgen, Rainer, E-mail: pottgen@uni-muenster.de

    2013-07-15T23:59:59.000Z

    Samples of SrAgZn and EuAgZn were synthesized by reaction of the elements in sealed tantalum crucibles. Both structures were refined on the basis of single crystal X-ray diffractometer data: KHg{sub 2}-type, Imma, a=476.7(1), b=780.9(2), c=810.1(2) pm, R{sub 1}/wR{sub 2}=0.0189/0.0119, 381 F² values for SrAg{sub 1.12}Zn{sub 0.88} and a=474.43(9), b=760.8(2), c=799.0(2) pm, R{sub 1}/wR{sub 2}=0.0226/0.0483, 370 F² values for EuAg{sub 1.17}Zn{sub 0.83} with 13 variables per refinement. Silver and zinc are randomly distributed on the Hg position and build up three-dimensional networks. EuAgZn shows ferromagnetic ordering at 29(1) K. In the temperature range from 75 to 300 K the sample shows Curie–Weiss behaviour with ?{sub eff}=7.87(1) ?{sub B}/Eu atom and ?{sub P}=37.1(1) K, indicating divalent europium. {sup 151}Eu Mössbauer spectroscopic measurements confirmed the divalent state with an isomer shift of ?9.31 mm/s at 78 K. Temperature dependent {sup 151}Eu data show first magnetic hyperfine field splitting at 25 K and a saturated magnetization of 17 T at 5.2 K. The temperature dependence can be described by an S=7/2 Brillouin function. - Graphical abstract: The near neighbor coordination of the strontium and europium atoms in SrAg{sub 1.12}Zn{sub 0.88}, EuAg{sub 1.17}Zn{sub 0.83}, and EuAuZn. - Highlights: • Synthesis of new intermetallic zinc compounds SrAgZn and EuAgZn. • Ferromagnetic ordering of EuAgZn at 29 K. • Magnetic hyperfine field splitting in the {sup 151}Eu Mössbauer spectrum.

  17. Manufacturing Process Optimization to Improve Stability, Yield and Efficiency of CdS/CdTe PV Devices: Final Report, December 2004 - January 2009

    SciTech Connect (OSTI)

    Sampath, W. S.; Enzenroth, A.; Barth, K.

    2009-03-01T23:59:59.000Z

    The research by Colorado State University advances the understanding of device stability, efficiency, and process yield for CdTe PV devices.

  18. Luminescence properties of ZnO layers grown on Si-on-insulator substrates

    SciTech Connect (OSTI)

    Kumar, Bhupendra; Gong, Hao; Vicknesh, S.; Chua, S. J.; Tripathy, S. [Department of Materials Science and Engineering, National University of Singapore, 119260 Singapore (Singapore); Institute of Materials Research and Engineering, 3 Research Link, 117602 Singapore (Singapore)

    2006-10-02T23:59:59.000Z

    The authors report on the photoluminescence properties of polycrystalline ZnO thin films grown on compliant silicon-on-insulator (SOI) substrates by radio frequency magnetron sputtering. The ZnO thin films on SOI were characterized by micro-Raman and photoluminescence (PL) spectroscopy. The observation of E{sub 2}{sup high} optical phonon mode near 438 cm{sup -1} in the Raman spectra of the ZnO samples represents the wurtzite crystal structure. Apart from the near-band-edge free exciton (FX) transition around 3.35 eV at 77 K, the PL spectra of such ZnO films also showed a strong defect-induced violet emission peak in the range of 3.05-3.09 eV. Realization of such ZnO layers on SOI would be useful for heterointegration with SOI-based microelectronics and microelectromechanical systems.

  19. Optical and phonon properties of ZnO:CuO mixed nanocomposite

    SciTech Connect (OSTI)

    Udayabhaskar, R.; Karthikeyan, B., E-mail: bkarthik@nitt.edu [Department of Physics, National Institute of Technology, Tiruchirappalli 620 015 (India)

    2014-04-21T23:59:59.000Z

    Optical and phonon properties of ZnO:CuO nanocrystals which are prepared through sol-gel method are reported here. From X-ray diffraction studies, observed that Cu doping replaces the Zn and also forms secondary phase. Optical absorption spectral studies shows that the exciton and plasmon related bands of ZnO and CuO phase, respectively. Fluorescence studies of the prepared samples shows that green emission from ZnO is completely depleted and the same is attributed to CuO Plasmon. Raman spectral studies reveal that secondary phase (impurity) induced profile changes in 1LO and E{sub 2High} modes. Asymmetry in peak shape is analyzed using Fano profile with the combination of Lorentzian profile. Moreover, the monotonic increase of Fano factor and full width at half maxima is hopefully attributed to the continuum arises by the plasmons of Cu-O phase in ZnO nanosystem.

  20. Heteroepitaxial ZnO films on diamond: Optoelectronic properties and the role of interface polarity

    SciTech Connect (OSTI)

    Schuster, Fabian, E-mail: Fabian.Schuster@wsi.tum.de; Hetzl, Martin; Garrido, Jose A.; Stutzmann, Martin [Walter Schottky Institut, Technische Universität München, Am Coulombwall 4, 85748 Garching (Germany); Magén, Cesar [Laboratorio de Microscopías Avanzadas (LMA) - Instituto de Nanociencia de Aragon (INA) and Departamento de Física de la Materia Condensada, Universidad de Zaragoza, 50018 Zaragoza (Spain); Fundación ARAID, 50018 Zaragoza (Spain); Arbiol, Jordi [Institut de Ciència de Materials de Barcelona, ICMAB-CSIC, Campus de la UAB, 08193 Bellaterra, CAT (Spain); Institució Catalana de Recerca i Estudis Avançats (ICREA), 08010 Barcelona, CAT (Spain)

    2014-06-07T23:59:59.000Z

    We demonstrate the growth of heteroepitaxial ZnO films on (110) diamond substrates by molecular beam epitaxy and report on a major advance in structural quality, as confirmed by XRD and high-resolution TEM measurements. The growth direction is found to be along the polar c-axis with Zn-polarity, deduced from annular bright-field scanning transmission electron microscopy imaging. This is important information, as simulations of the electronic band structure reveal the ZnO polarity to dominate the electronic structure of the interface: the formation of a two-dimensional electron gas on the ZnO side or a two-dimensional hole gas on the diamond side are predicted for Zn- and O-polarity, respectively. In addition, photoluminescence and absorption studies exhibit good optical properties and reveal stimulated emission for optical excitation above a threshold of 30?kW/cm{sup 2}.

  1. First-principles study of polarization in Zn1-xMgxO Andrei Malashevich* and David Vanderbilt

    E-Print Network [OSTI]

    Vanderbilt, David

    August 2006; published 4 January 2007 Wurtzite ZnO can be substituted with up to 30% MgO to form a metastable Zn1-xMgxO alloy while still retaining the wurtzite structure. Because this alloy has a larger band. INTRODUCTION Recently, much attention has been paid to wurtzite Zn1-xMgxO alloys as candidates for applications

  2. Phonon deformation potentials in wurtzite GaN and ZnO determined by uniaxial pressure dependent Raman measurements

    E-Print Network [OSTI]

    Nabben, Reinhard

    Phonon deformation potentials in wurtzite GaN and ZnO determined by uniaxial pressure dependent deformation potentials in wurtzite GaN and ZnO determined by uniaxial pressure dependent Raman measurements G online 9 February 2011 We report the phonon deformation potentials of wurtzite GaN and ZnO for all zone

  3. Effects of Cu, Zn, and S application to peach trees (Prunus persica (L.) Batsch.) on an east Texas soil

    E-Print Network [OSTI]

    Powell, Jason Cory

    1994-01-01T23:59:59.000Z

    treatment was replicated 4 times. Sulfur and Cu treatments were applied in January followed by three separate Zn foliar sprays in March, April, and May. Responses were linear between applied Zn and foliar Zn, applied S and foliar S, and applied S and leaf...

  4. Adsorption and Diffusion of Hydrogen in a New Metal-Organic Framework Material: [Zn(bdc)(ted)0.5

    E-Print Network [OSTI]

    Li, Jing

    Adsorption and Diffusion of Hydrogen in a New Metal-Organic Framework Material: [Zn(bdc)(ted)0.5 pressure of 50 bar in a recently developed metal-organic framework material, [Zn(bdc)(ted)0.5] (bdc equilibrium molecular dynamics to compute self- and transport diffusivities of hydrogen in [Zn(bdc)(ted)0.5

  5. Corrosion Protection of Steel Using Nonanomalous Ni-Zn-P Basker Veeraraghavan,* Bala Haran,** Swaminatha P. Kumaraguru,*

    E-Print Network [OSTI]

    Popov, Branko N.

    Corrosion Protection of Steel Using Nonanomalous Ni-Zn-P Coatings Basker Veeraraghavan,* Bala Haran on the corrosion resistance of the final deposit. Coatings with 16.2 wt % Zn were found to display a potential of 0 of the coating and the surface morphology. Corrosion studies in corroding media show that Ni-Zn-P coatings

  6. Stability of ZnMgO oxide in a weak alkaline solution E. Diler1,2

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    -dissolution of ZnO is negligible: indeed, both processes reduce significantly the efficiency of photocatalysisO sample. This alloy, thus, constitutes an alternative to the use of ZnO in photocatalysis applications cells, photodetectors, light emitting diodes, magnetic storage and photocatalysis. In some cases, Zn

  7. Phase transformation of ZnMoO{sub 4} by localized thermal spike

    SciTech Connect (OSTI)

    Agarwal, D. C.; Avasthi, D. K.; Kabiraj, D. [Inter-University Accelerator Center, Aruna Asaf Ali Marg, New Delhi 110067 (India); Varma, S. [Institute of Physics, Sachivalaya Marg, Bhubaneswar 751005 (India); Kremer, Felipe; Ridgway, M. C. [Australian National University, Canberra ACT 0200 (Australia)

    2014-04-28T23:59:59.000Z

    We show that ZnMoO{sub 4} remains in stable phase under thermal annealing up to 1000?°C, whereas it decomposes to ZnO and MoO{sub 3} under transient thermal spike induced by 100?MeV Ag irradiation. The transformation is evidenced by X-ray diffraction (XRD), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). Thin films of ZnMoO{sub 4} were synthesized by thermal evaporation and subsequent annealing in oxygen ambient at 600?°C for 4?h. XRD results show that as the irradiation fluence increases, the peak related to ZnMoO{sub 4} decreases gradually and eventually disappear, whereas peaks related to ZnO grow steadily up to fluence of 3?×?10{sup 12} ions/cm{sup 2} and thereafter remain stable till highest fluence. This indicates that polycrystalline ZnMoO{sub 4} film has transformed to polycrystalline ZnO thin film. The Raman lines related to ZnMoO{sub 4} are observed to have disappeared with increasing irradiation fluence. XPS results show modification in bonding and depletion of Mo from near surface region after the ion irradiation. Cross-sectional transmission electron microscopy result shows the formation of ion track of diameter 12–16?nm. These results demonstrate that ion beam methods provide the means to control phase splitting of ZnMoO{sub 4} to ZnO and MoO{sub 3} within nanometric dimension along the ion track. The observation of phase splitting and Mo loss are explained in the framework of ion beam induced thermal spike formalism.

  8. Development of ZnO:Ga as an Ultrafast Scintillator

    SciTech Connect (OSTI)

    Bourret-Courchesne, E.D.; Derenzo, S.E.; Weber, M.J.

    2008-12-10T23:59:59.000Z

    We report on several methods for synthesizing the ultra-fast scintillator ZnO(Ga), and measurements of the resulting products. This material has characteristics that make it an excellent alpha detector for tagging the time and direction of individual neutrons produced by t-d and d-d neutron generators (associated particle imaging). The intensity and decay time are strongly dependent on the method used for dopant incorporation. We compare samples made by diffusion of Ga metal to samples made by solid state reaction between ZnO and Ga2O3 followed by reduction in hydrogen. The latter is much more successful and has a pure, strong near-band-edge fluorescence and an ultra-fast decay time of the x-ray-excited luminescence. The luminescence increases dramatically as the temperature is reduced to 10K. We also present results of an alternate low-temperature synthesis that produces luminescent particles with a more uniform size distribution. We examine possible mechanisms for the bright near-band-edge scintillation and favor the explanation that it is due to the recombination of Ga3+ donor electrons with ionization holes trapped on H+ ion acceptors.

  9. Charge transport properties of CdMnTe radiation detectors

    SciTech Connect (OSTI)

    Kim K.; Rafiel, R.; Boardman, M.; Reinhard, I.; Sarbutt, A.; Watt, G.; Watt, C.; Uxa, S.; Prokopovich, D.A.; Belas, E.; Bolotnikov, A.E.; James, R.B.

    2012-04-11T23:59:59.000Z

    Growth, fabrication and characterization of indium-doped cadmium manganese telluride (CdMnTe)radiation detectors have been described. Alpha-particle spectroscopy measurements and time resolved current transient measurements have yielded an average charge collection efficiency approaching 100 %. Spatially resolved charge collection efficiency maps have been produced for a range of detector bias voltages. Inhomogeneities in the charge transport of the CdMnTe crystals have been associated with chains of tellurium inclusions within the detector bulk. Further, it has been shown that the role of tellurium inclusions in degrading chargecollection is reduced with increasing values of bias voltage. The electron transit time was determined from time of flight measurements. From the dependence of drift velocity on applied electric field the electron mobility was found to be n = (718 55) cm2/Vs at room temperature.

  10. High pressure behavior of otavite (CdCo3)

    SciTech Connect (OSTI)

    Minch, R.; Ehm, L.; Seoung, D.H.; Winkler, B.; Knorr, K.; Peters, L.; Borkowski, L.A.; Parise, J.B.; Lee, Y.; Dubrovinsky, L.; Depmeier, W.

    2010-08-24T23:59:59.000Z

    The high-pressure, room temperature behavior of otavite (CdCO{sub 3}) was investigated by angle-dispersive synchrotron radiation powder diffraction up to 40 GPa, Raman spectroscopy up to 23 GPa and quantum mechanical calculations based on density functional theory. The calcite-type structure of CdCO{sub 3} is stable up to at least {approx}19 GPa as shown by Raman spectroscopy. The compression mechanism was obtained from structure refinements against the diffraction data. The quantum mechanical calculations propose a calcite-aragonite phase transition to occur at about 30 GPa. The existence of a pressure-induced phase transition is supported by the Raman and diffraction experiments. Evidence for the transformation is given by broadening of X-ray reflections and external Raman bands starting from about 19 GPa in both experiments.

  11. High Spin Spectroscopy and Shape Evolution in 105Cd

    E-Print Network [OSTI]

    M. Kumar Raju; D. Negi; S. Muralithar; R. P. Singh; J. A. Sheikh; G. H. Bhat; R. Kumar; Indu Bala; T. Trivedi; A. Dhal; K. Rani; R. Gurjar; D. Singh; R. Palit; B. S. Naidu; S. Saha; J. Sethi; R. Donthi; S. Jadhav

    2015-01-30T23:59:59.000Z

    High spin states in 105Cd were studied using 16O beam on 92Mo reaction at an incident beam energy of 75 MeV. The level scheme of 105Cd has been observed up to an excitation energy of 10.8 MeV with the addition of 30 new gamma transitions to the previous work. Spin and parity for most of the reported levels are assigned from the DCO ratios and linear polarization measurements. The microscopic origin of the investigated band structures is discussed in the context of triaxial projected shell model. The energies of observed positive and negative parity bands agree with the predictions of the TPSM by considering triaxial deformation for the observed excited band structures. The shape evolution with increasing angular momentum is explained in the framework of Cranked Shell Model and the Total Routhian Surface calculations.

  12. Modulation of Rhamm (CD168) for selective adipose tissue development

    DOE Patents [OSTI]

    Turley, Eva A; Bissell, Mina J

    2014-05-06T23:59:59.000Z

    Herein is described the methods and compositions for modulation of Rhamm, also known as CD 186, and its effects on wound repair, muscle differentiation, bone density and adipogeneisis through its ability to regulate mesenchymal stem cell differentiation. Compositions and methods are provided for blocking Rhamm function for selectively increasing subcutaneous, but not, visceral fat. Compositions and methods for modulating Rhamm in wound repair are also described.

  13. Crystal orientation mechanism of ZnTe epilayers formed on different orientations of sapphire substrates by molecular beam epitaxy

    SciTech Connect (OSTI)

    Nakasu, T., E-mail: n-taizo.nakasu@asagi.waseda.jp; Yamashita, S.; Aiba, T.; Hattori, S.; Sun, W.; Taguri, K.; Kazami, F. [Department of Electrical Engineering and Bioscience, Waseda University, Tokyo 169-8555 (Japan); Kobayashi, M. [Department of Electrical Engineering and Bioscience, Waseda University, Tokyo 169-8555 (Japan); Kagami Memorial Research Institute for Materials and Technology, Waseda University, Tokyo 169-0051 (Japan)

    2014-10-28T23:59:59.000Z

    The electrooptic effect in ZnTe has recently attracted research attention, and various device structures using ZnTe have been explored. For application to practical terahertz wave detector devices based on ZnTe thin films, sapphire substrates are preferred because they enable the optical path alignment to be simplified. ZnTe/sapphire heterostructures were focused upon, and ZnTe epilayers were prepared on highly mismatched sapphire substrates by molecular beam epitaxy. Epitaxial relationships between the ZnTe thin films and the sapphire substrates with their various orientations were investigated using an X-ray diffraction pole figure method. (0001) c-plane, (1-102) r-plane, (1-100) m-plane, and (11-20) a-plane oriented sapphire substrates were used in this study. The epitaxial relationship between ZnTe and c-plane sapphire was found to be (111) ZnTe//(0001) sapphire with an in-plane orientation relationship of [?211] ZnTe//[1-100] sapphire. It was found that the (211)-plane ZnTe layer was grown on the m-plane of the sapphire substrates, and the (100)-plane ZnTe layer was grown on the r-plane sapphire. When the sapphire substrates were inclined from the c-plane towards the m-axis direction, the orientation of the ZnTe thin films was then tilted from the (111)-plane to the (211)-plane. The c-plane of the sapphire substrates governs the formation of the (111) ZnTe domain and the ZnTe epilayer orientation. These crystallographic features were also related to the atom arrangements of ZnTe and sapphire.

  14. Optimization of chemical bath deposited CdS thin films using nitrilotriacetic acid as a complexing agent

    E-Print Network [OSTI]

    Chow, Lee

    thin film solar cells based on CdTe or CIGS [1,2]. CdS has also been used in other applications. The highest efficiencies reported for both CdTe and CIGS solar cells were obtained when chemical bath is known to greatly enhance the performance of CdS windows used in the above mentioned solar cells

  15. Design and Investigation of Micro-Patterned Injection-Moulded Polymer Substrates for Use in CD-based Microfluidics

    E-Print Network [OSTI]

    Mustakerov, Ivan

    -based Microfluidics for Cell Manipulation ICOMM/4M 2010 No. 63 D. Trifonov1 , K. Kostadinov2 , M. Al-Wahab3 , V. Kotev MOULDING AND CD - BASED MICROFLUIDIC DEVICES Micro- and nanostructures can be replicated on polymer- devices like CD microfluidic platform for Bio-MEMS applications, Lab-on-a-CD, CD centrifugal mi

  16. Residual and nitrogen doping of homoepitaxial nonpolar m-plane ZnO films grown by molecular beam epitaxy

    SciTech Connect (OSTI)

    Taienoff, D.; Deparis, C.; Teisseire, M.; Morhain, C. [Centre de Recherche sur l'Hetero-Epitaxie et ses Applications, Centre National de la Recherche Scientifique (CRHEA-CNRS), Rue B. Gregory, F-06560 Valbonne Sophia Antipolis (France); Al-Khalfioui, M.; Vinter, B.; Chauveau, J.-M. [Centre de Recherche sur l'Hetero-Epitaxie et ses Applications, Centre National de la Recherche Scientifique (CRHEA-CNRS), Rue B. Gregory, F-06560 Valbonne Sophia Antipolis (France); Universite de Nice Sophia Antipolis, Parc Valrose F-06103 Nice (France)

    2011-03-28T23:59:59.000Z

    We report the homoepitaxial growth by molecular beam epitaxy of high quality nonpolar m-plane ZnO and ZnO:N films over a large temperature range. The nonintentionally doped ZnO layers exhibit a residual doping as low as {approx}10{sup 14} cm{sup -3}. Despite an effective incorporation of nitrogen, p-type doping was not achieved, ZnO:N films becoming insulating. The high purity of the layers and their low residual n-type doping evidence compensation mechanisms in ZnO:N films.

  17. High Efficiency CdTe/CdS Thin Film solar Cells by a Process Suitable for Large Scale Production. N. Romeo, A. Bosio, A. Romeo, M. Bianucci, L. Bonci, C. Lenti

    E-Print Network [OSTI]

    Romeo, Alessandro

    High Efficiency CdTe/CdS Thin Film solar Cells by a Process Suitable for Large Scale Production. N-mail:Nicola.Romeo@fis.unipr.it ABSTRACT: It has been demonstrated that CdTe/CdS thin film solar cells can exhibit an efficiency around 16 diffusor in CdTe and at a long run it can segregates at the grain boundaries damaging the solar cell

  18. Approved Module Information for AM30CD, 2014/5 Module Title/Name: Chaos and Dynamical Systems Module Code: AM30CD

    E-Print Network [OSTI]

    Neirotti, Juan Pablo

    Module Code: AM30CD School: Engineering and Applied Science Module Type: Standard Module New Module Module Aims: The aims of AM30CD are to provide the necessary mathematical tools to support the study hours Total Learning Hours: 100 hours Learning & Teaching Rationale: Lectures/Tutorials Module

  19. In situ corrosion analysis of Al-Zn-In-Mg-Ti-Ce sacrificial anode alloy

    SciTech Connect (OSTI)

    Ma Jingling, E-mail: majingling.student@sina.com; Wen Jiuba; Zhai Wenxia; Li Quanan

    2012-03-15T23:59:59.000Z

    The corrosion behaviour of Al-5Zn-0.02In-1Mg-0.05Ti-0.5Ce (wt.%) alloy has been investigated by immersion test, scanning electron microscopy, energy dispersive X-ray detector, electrochemical impedance spectroscopy and electrochemical noise. The results show that there exist different corrosion types of the alloy in 3.5% NaCl solution with the immersion time. At the initial stage of immersion, pitting due to the precipitates predominates the corrosion with a typical inductive loop at low frequencies in electrochemical impedance spectroscopy. The major precipitates of the alloy are MgZn{sub 2} and Al{sub 2}CeZn{sub 2} particles. The corrosion potentials of the bulk MgZn{sub 2} and Al{sub 2}CeZn{sub 2} alloys are negative with respect to that of {alpha}-Al, so the MgZn{sub 2} and Al{sub 2}CeZn{sub 2} precipitates can act as activation centre and cause the pitting. In the late corrosion, a relative uniform corrosion predominates the corrosion process controlled by the dissolution/precipitation of the In ions and characterized by a capacitive loop at medium-high frequencies in electrochemical impedance spectroscopy. The potential noise of the pitting shows larger amplitude fluctuation and lower frequency, but the potential noise of the uniform corrosion occurs with smaller amplitude fluctuation and higher frequency.

  20. Ethanol Steam Reforming on Co/CeO2: The Effect of ZnO Promoter

    SciTech Connect (OSTI)

    Davidson, Stephen; Sun, Junming; Wang, Yong

    2013-12-02T23:59:59.000Z

    A series of ZnO promoted Co/CeO2 catalysts were synthesized and characterized using XRD, TEM, H2-TPR, CO chemisorption, O2-TPO, IR-Py, and CO2-TPD. The effects of ZnO on the catalytic performances of Co/CeO2 were studied in ethanol steam reforming. It was found that the addition of ZnO facilitated the oxidation of Co0 via enhanced oxygen mobility of the CeO2 support which decreased the activity of Co/CeO2 in C–C bond cleavage of ethanol. 3 wt% ZnO promoted Co/CeO2 exhibited minimum CO and CH4 selectivity and maximum CO2 selectivity. This resulted from the combined effects of the following factors with increasing ZnO loading: (1) enhanced oxygen mobility of CeO2 facilitated the oxidation of CHx and CO to form CO2; (2) increased ZnO coverage on CeO2 surface reduced the interaction between CHx/CO and Co/CeO2; and (3) suppressed CO adsorption on Co0 reduced CO oxidation rate to form CO2. In addition, the addition of ZnO also modified the surface acidity and basicity of CeO2, which consequently affected the C2–C4 product distributions.

  1. Physical properties of GdFe 2 (Al x Zn 1 ? x ) 20

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ni, N.; Jia, S.; Samolyuk, G. D.; Kracher, A.; Sefat, A. S.; Bud’ko, S. L.; Canfield, P. C.

    2011-02-01T23:59:59.000Z

    The high ferromagnetic ordering temperature of the dilute, rare-earth-bearing, intermetallic compound GdFe?Zn?? has been understood as being the consequence of the Gd³? moment being embedded in a nearly ferromagnetic Fermi liquid. To test this understanding in detail, single crystals of the pseudoternary series GdFe?(AlxZn1-x)?? (x?0.122) and YFe?(AlxZn1-x)?? (x?0.121) were grown out of Zn-rich solution. Magnetization, heat capacity, and resistivity measurements show that, with Al doping, the ferromagnetic phase transition temperatures of the GdFe?(AlxZn1-x)?? compounds decrease from 86 K (x= 0) to 10 K (x= 0.122); for the nonmagnetic analog, the YFe?(AlxZn1-x)?? series, the Stoner enhancement factor Z decreases from 0.88 (x= 0) to 0.35 (x= 0.121) in a similar manner. Tight-binding linear-muffin-tin orbital atomic-sphere approximation band structure calculations are used to rationalize this trend. These results, together with the earlier studies of the R(Fe1-xCox)?Zn?? (R= Gd and Y) series, clearly highlight the importance of band filling and the applicability of even a simple, rigid-band model to these compounds.

  2. Paramagnetism and antiferromagnetic interactions in single-phase Fe-implanted ZnO

    E-Print Network [OSTI]

    Pereira, Lino Miguel da Costa; Correia, João Guilherme; Van Bael, M J; Temst, Kristiaan; Vantomme, André; Araújo, João Pedro

    2013-01-01T23:59:59.000Z

    As the intrinsic origin of the high temperature ferromagnetism often observed in wide-gap dilute magnetic semiconductors becomes increasingly debated, there is a growing need for comprehensive studies on the single-phase region of the phase diagram of these materials. Here we report on the magnetic and structural properties of Fe-doped ZnO prepared by ion implantation of ZnO single crystals. A detailed structural characterization shows that the Fe impurities substitute for Zn in ZnO in a wurtzite Zn$_{1?x}$Fe$_{x}$O phase which is coherent with the ZnO host. In addition, the density of beam-induced defects is progressively decreased by thermal annealing up to 900$^ {?}$C, from highly disordered after implantation to highly crystalline upon subsequent annealing. Based on a detailed analysis of the magnetometry data, we demonstrate that isolated Fe impurities occupying Zn substitutional sites behave as localized paramagnetic moments down to 2 K, irrespective of the Fe concentration and the density of beam-i...

  3. Identification of As-vacancy complexes in Zn-diffused GaAs

    SciTech Connect (OSTI)

    Elsayed, M. [Department of Physics, Martin Luther University Halle, 06099 Halle (Germany); Department of Physics, Faculty of Science, Minia University, 61519 Minia (Egypt); Krause-Rehberg, R. [Department of Physics, Martin Luther University Halle, 06099 Halle (Germany); Korff, B. [Bremen Center for Computational Materials Science, University Bremen, 28359 Bremen (Germany); Richter, S. [Fraunhofer Center for Silicon Photovoltaics CSP, 06120 Halle (Saale) (Germany); Leipner, H. S. [Center of Materials Science, Martin Luther University Halle, 06099 Halle (Germany)

    2013-03-07T23:59:59.000Z

    We have used positron annihilation spectroscopy to study the introduction of point defects in Zn-diffused semi-insulating GaAs. The diffusion was performed by annealing the samples for 2 h at 950 Degree-Sign C. The samples were etched in steps of 7 {mu}m. Both Doppler broadening using slow positron beam and lifetime spectroscopy studies were performed after each etching step. Both techniques showed the existence of vacancy-type defects in a layer of about 45 {mu}m. Secondary ion mass spectroscopy measurements illustrated the presence of Zn at high level in the sample almost up to the same depth. Vacancy-like defects as well as shallow positron traps were observed by lifetime measurements. We distinguish two kinds of defects: As vacancy belongs to defect complex, bound to most likely one Zn atom incorporated on Ga sublattice, and negative-ion-type positron traps. Zn acceptors explained the observation of shallow traps. The effect of Zn was evidenced by probing GaAs samples annealed under similar conditions but without Zn treatment. A defect-free bulk lifetime value is detected in this sample. Moreover, our positron annihilation spectroscopy measurements demonstrate that Zn diffusion in GaAs system is governed by kick-out mechanism.

  4. ZnO nanorod growth by plasma-enhanced vapor phase transport with different growth durations

    SciTech Connect (OSTI)

    Kim, Chang-Yong; Oh, Hee-bong [Department of Nano Science and Engineering, Inje University, Obang-dong, Gimhae, Gyeongnam 621-749 (Korea, Republic of); Ryu, Hyukhyun, E-mail: hhryu@inje.ac.kr [Department of Nano Science and Engineering, Center for Nano Manufacturing, Inje University, Obang-dong, Gimhae, Gyeongnam 621-749 (Korea, Republic of); Yun, Jondo [Department of Nano Science and Engineering, Kyungnam University, Changwon, Gyeongnam 631-701 (Korea, Republic of); Lee, Won-Jae [Department of Materials and Components Engineering, Dong-Eui University, 995 Eomgwangno, Busanjin-gu, Busan 614-714 (Korea, Republic of)

    2014-09-01T23:59:59.000Z

    In this study, the structural properties of ZnO nanostructures grown by plasma-enhanced vapor phase transport (PEVPT) were investigated. Plasma-treated oxygen gas was used as the oxygen source for the ZnO growth. The structural properties of ZnO nanostructures grown for different durations were measured by scanning electron microscopy, x-ray diffraction, and transmission electron microscopy. The authors comprehensively analyzed the growth of the ZnO nanostructures with different growth durations both with and without the use of plasma-treated oxygen gas. It was found that PEVPT has a significant influence on the growth of the ZnO nanorods. PEVPT with plasma-treated oxygen gas facilitated the generation of nucleation sites, and the resulting ZnO nanorod structures were more vertical than those prepared by conventional VPT without plasma-treated oxygen gas. As a result, the ZnO nanostructures grown using PEVPT showed improved structural properties compared to those prepared by the conventional VPT method.

  5. Low temperature atomic layer deposited ZnO photo thin film transistors

    SciTech Connect (OSTI)

    Oruc, Feyza B.; Aygun, Levent E.; Donmez, Inci; Biyikli, Necmi; Okyay, Ali K., E-mail: aokyay@ee.bilkent.edu.tr [Institute of Materials Science and Nanotechnology, Bilkent University, Bilkent, 06800 Ankara (Turkey); UNAM—National Nanotechnology Research Center, Bilkent University, Bilkent, 06800 Ankara (Turkey); Department of Electrical and Electronics Engineering, Bilkent University, Bilkent, 06800 Ankara (Turkey); Yu, Hyun Yong [The School of Electrical Engineering, Korea University, Seoul 136-701 (Korea, Republic of)

    2015-01-01T23:59:59.000Z

    ZnO thin film transistors (TFTs) are fabricated on Si substrates using atomic layer deposition technique. The growth temperature of ZnO channel layers are selected as 80, 100, 120, 130, and 250?°C. Material characteristics of ZnO films are examined using x-ray photoelectron spectroscopy and x-ray diffraction methods. Stoichiometry analyses showed that the amount of both oxygen vacancies and interstitial zinc decrease with decreasing growth temperature. Electrical characteristics improve with decreasing growth temperature. Best results are obtained with ZnO channels deposited at 80?°C; I{sub on}/I{sub off} ratio is extracted as 7.8 × 10{sup 9} and subthreshold slope is extracted as 0.116 V/dec. Flexible ZnO TFT devices are also fabricated using films grown at 80?°C. I{sub D}–V{sub GS} characterization results showed that devices fabricated on different substrates (Si and polyethylene terephthalate) show similar electrical characteristics. Sub-bandgap photo sensing properties of ZnO based TFTs are investigated; it is shown that visible light absorption of ZnO based TFTs can be actively controlled by external gate bias.

  6. Thin Metal Oxide Films to Modify a Window Layer in CdTe-Based Solar Cells for Improved Performance

    SciTech Connect (OSTI)

    Lemmon, John P.; Polikarpov, Evgueni; Bennett, Wendy D.; Kovarik, Libor

    2012-05-05T23:59:59.000Z

    We report on CdS/CdTe photovoltaic devices that contain a thin Ta2O5 film deposited onto the CdS window layer by sputtering. We show that for thicknesses below 5 nm, Ta2O5 films between CdS and CdTe positively affect the solar cell performance, improving JSC, VOC, and the cell power conversion efficiency despite the insulating nature of the interlayer material. Using the Ta2O5 interlayer, a VOC gain of over 100 mV was demonstrated compared to a CdTe/CdS baseline. Application of a 1nm Ta2O5 interlayer enabled the fabrication of CdTe solar cells with extremely thin (less than 30 nm) CdS window layers. The efficiency of these cells exceeded that of a base line cell with 95 nm of CdS.

  7. Temperature dependence of the elastic constants of solid and liquid Cd0.96Zn0.04Te obtained by laser ultrasound

    E-Print Network [OSTI]

    Wadley, Haydn

    infrared focal plane array IRFPA sensors.1­3 As the size of imaging detectors continues to increase, a need a complete evaluation of the temperature dependent single crystal elastic stiffness constants C11 , C12 , C44 for the solid and the adiabatic bulk modulus (KS) for the liquid. In addition, evaluation of the thermoelastic

  8. The Antimony-Based Type I Clathrate compounds Cs8Cd18Sb28 and Cs8Zn18Sb28**

    SciTech Connect (OSTI)

    Liu, Yi; Wu, Li-Ming; Li, Long-Hua; Du, Shao-Wu; Corbett, John D.; Chen, Ling

    2009-06-17T23:59:59.000Z

    The title compounds lie in a new region of phase space for such a structure, and have stoichiometries in accord with a classical Zintl phase formulation. The small semiconductor gaps indicated by DFT calculations are also supported by their diamagnetic susceptibilities.

  9. FINAL REPORT OF RESEARCH ON CuxS/ (Cd,Zn)S PHOTOVOLTAIC SOLAR ENERGY CONVERTERS 3/77 - 9/79

    E-Print Network [OSTI]

    Chin, B.L.

    2013-01-01T23:59:59.000Z

    and possibly (3) higher short-circuit current because of afilm (8249), the short-circuit current increased while thenoise ratio of the short-circuit current and thermopile (

  10. Direct measurement of product of the electron mobility and mean free drift time of CdZnTe semiconductors using position sensitive single

    E-Print Network [OSTI]

    He, Zhong

    Institute of Physics. Related Articles A new detector for mass spectrometry: Direct detection of low energy of material trends in nonproportionality of scintillators J. Appl. Phys. 109, 123716 (2011) A digital method Rev. Sci. Instrum. 81, 10E503 (2010) Development of a thermal neutron detector based on scintillating

  11. An inter-laboratory study to test the ability of amendments to reduce the availability of Cd, Pb, and Zn in situ

    E-Print Network [OSTI]

    Brown, Sally

    (RM), cyclonic ashes (CA), biosolids (BIO), and water treatment residuals (WTR). Both soil solution Abbreviations: BIO, biosolids; WTR, water treatment residuals; RM, red mud; KAD, kaolin amorphous derivatives

  12. Persisting impact of historical mining activity to metal (Pb, Zn, Cd, Tl, Hg) and metalloid (As, Sb) enrichment in sediments of the Gardon River,

    E-Print Network [OSTI]

    Demouchy, Sylvie

    ) enrichment in sediments of the Gardon River, Southern France Eléonore Resongles a, , Corinne Casiot a , Rémi in sediments was investigated in multi-source context. · Metal(loid) enrichment during the 19th century of ancient mining activity on metal(loid) enrichment in sediments of a former mining watershed (Gardon River

  13. Subbarrier fusion of {sup 9}Li with {sup 70}Zn

    SciTech Connect (OSTI)

    Loveland, W.; Vinodkumar, A. M.; Naik, R. S.; Sprunger, P. H.; Matteson, B.; Neeway, J. [Department of Chemistry, Oregon State University, Corvallis, Oregon 97331 (United States); Trinczek, M.; Dombsky, M.; Machule, P.; Ottewell, D. [TRIUMF, Vancouver, British Columbia, V6T 2A3 (Canada); Cross, D. [TRIUMF, Vancouver, British Columbia, V6T 2A3 (Canada); Department of Chemistry, Simon Fraser University, Burnaby, British Columbia, V5A 1S6 (Canada); Gagnon, K.; Mills, W. J. [TRIUMF, Vancouver, British Columbia, V6T 2A3 (Canada); Department of Physics, Simon Fraser University, Burnaby, British Columbia, V5A 1S6 (Canada)

    2006-12-15T23:59:59.000Z

    The cross section for the fusion of {sup 9}Li with {sup 70}Zn was measured for seven projectile energies spanning the subbarrier and near-barrier region (E{sub c.m.} ranging from 9.7 to 13.4 MeV) using the ISAC facility at TRIUMF. {gamma}-ray spectroscopy of the irradiated target foils along with {beta} counting of the chemically separated Ge and As evaporation residues were used to measure the fusion cross sections. Statistical model calculations were used to correct for the yields of any unobserved nuclei. The observed fusion excitation function shows significant subbarrier fusion enhancement with a large deduced value of the fusion radius, R{sub B}=12.1{+-}1.0 fm. Coupled-channels calculations do not account for the observed subbarrier enhancement. The implications of this finding for understanding the fusion of {sup 11}Li are discussed.

  14. ZnO/porous-Si and TiO{sub 2}/porous-Si nanocomposite nanopillars

    SciTech Connect (OSTI)

    Wang, Dong, E-mail: dong.wang@tu-ilmenau.de; Yan, Yong; Schaaf, Peter [Chair Materials for Electronics, Institute of Materials Engineering and Institute of Micro- and Nanotechnologies MacroNano, TU Ilmenau, Gustav-Kirchhoff-Str. 5, 98693 Ilmenau (Germany); Sharp, Thomas [Oxford Instruments Plasma Technology Ltd., Yatton, Bristol BS49 4AP (United Kingdom); Schönherr, Sven; Ronning, Carsten [Institute for Solid State Physics, Friedrich Schiller University Jena, Max-Wien-Platz 1, 07743 Jena (Germany); Ji, Ran [SUSS MicroTec Lithography GmbH, Schleissheimer Str. 90, 85748 Garching (Germany)

    2015-01-01T23:59:59.000Z

    Porous Si nanopillar arrays are used as templates for atomic layer deposition of ZnO and TiO{sub 2}, and thus, ZnO/porous-Si and TiO{sub 2}/porous-Si nanocomposite nanopillars are fabricated. The diffusion of the precursor molecules into the inside of the porous structure occurs via Knudsen diffusion and is strongly limited by the small pore size. The luminescence of the ZnO/porous-Si nanocomposite nanopillars is also investigated, and the optical emission can be changed and even quenched after a strong plasma treatment. Such nanocomposite nanopillars are interesting for photocatalysis and sensors.

  15. Inverse spin Hall effect induced by spin pumping into semiconducting ZnO

    SciTech Connect (OSTI)

    Lee, Jung-Chuan [Institute of Physics, Academia Sinica, Taipei 11529, Taiwan (China); Huang, Leng-Wei [Graduate Institute of Applied Physics, National Chengchi University, Taipei 11605, Taiwan (China); Hung, Dung-Shing, E-mail: dshung@mail.mcu.edu.tw [Institute of Physics, Academia Sinica, Taipei 11529, Taiwan (China); Department of Information and Telecommunications Engineering, Ming Chuan University, Taipei 111, Taiwan (China); Chiang, Tung-Han [Department of Physics, National Cheng Kung University, Tainan 70101, Taiwan (China); Huang, J. C. A., E-mail: jcahuang@mail.ncku.edu.tw [Department of Physics, National Cheng Kung University, Tainan 70101, Taiwan (China); Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan 70101, Taiwan (China); Liang, Jun-Zhi [Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan 70101, Taiwan (China); Department of Physics, Fu Jen Catholic University, Taipei 242, Taiwan (China); Lee, Shang-Fan, E-mail: leesf@phys.sinica.edu.tw [Institute of Physics, Academia Sinica, Taipei 11529, Taiwan (China); Graduate Institute of Applied Physics, National Chengchi University, Taipei 11605, Taiwan (China)

    2014-02-03T23:59:59.000Z

    The inverse spin Hall effect (ISHE) of n-type semiconductor ZnO thin films with weak spin-orbit coupling has been observed by utilizing the spin pumping method. In the ferromagnetic resonance condition, the spin pumping driven by the dynamical exchange interaction of a permalloy film injects a pure spin current into the adjacent ZnO layer. This spin current gives rise to a DC voltage through the ISHE in the ZnO layer, and the DC voltage is proportional to the microwave excitation power. The effect is sizeable even when the spin backflow is considered.

  16. Phosphorescence quenching by mechanical stimulus in CaZnOS:Cu

    SciTech Connect (OSTI)

    Tu, Dong; Kamimura, Sunao [National Institute of Advanced Industrial Science and Technology (AIST), Saga 841-0052 (Japan); Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, Fukuoka 816-8580 (Japan); Xu, Chao-Nan, E-mail: cn-xu@aist.go.jp [National Institute of Advanced Industrial Science and Technology (AIST), Saga 841-0052 (Japan); Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, Fukuoka 816-8580 (Japan); International Institute for Carbon-Neutral Energy Research (WPI-I2CNER), Kyushu University, Fukuoka 819-0395 (Japan); Fujio, Yuki; Sakata, Yoshitaro [National Institute of Advanced Industrial Science and Technology (AIST), Saga 841-0052 (Japan); Ueno, Naohiro [National Institute of Advanced Industrial Science and Technology (AIST), Saga 841-0052 (Japan); Graduate School of Science and Engineering, Saga University, Saga 840-8502 (Japan)

    2014-07-07T23:59:59.000Z

    We have found that phosphorescence intensity of CaZnOS:Cu decreased visibly under an applied load. This mechanical quenching (MQ) of phosphorescence in CaZnOS:Cu corresponded to the mechanical stimuli. We have thus demonstrated that the MQ of CaZnOS:Cu could be used for visualizing stress distributions in practical applications. We propose that MQ arises from non-radiative recombination due to electron-transfer from trap levels to non-radiative centers as a result of the mechanical load.

  17. Measurements of sputtered neutrals and ions and investigation of their roles on the plasma properties during rf magnetron sputtering of Zn and ZnO targets

    SciTech Connect (OSTI)

    Maaloul, L.; Stafford, L. [Département de Physique, Université de Montréal, Montréal, Québec H3C 3J7 (Canada)] [Département de Physique, Université de Montréal, Montréal, Québec H3C 3J7 (Canada)

    2013-11-15T23:59:59.000Z

    Langmuir probe and optical absorption spectroscopy measurements were used to determine the line-integrated electron density, electron temperature, and number density of Ar atoms in metastable {sup 3}P{sub 2} and {sup 3}P{sub 0} levels in a 5 mTorr, rf magnetron sputtering plasmas used for the deposition of ZnO-based thin films. While the average electron energy and density of Ar atoms in {sup 3}P{sub 2} and {sup 3}P{sub 0} excited states were fairly independent of self-bias voltage, the Ar {sup 3}P{sub 2}-to-electron number density ratio decreased by approximately a factor of 5 when going from ?115 V to ?300 V. This decrease was correlated to an increase by about one order of magnitude of the number density of sputtered Zn atoms determined by absolute actinometry measurements on Zn I using either Ar or Xe as the actinometer gas. These results were also found to be in excellent agreement with the predictions of a global model accounting for Penning ionization of sputtered Zn particles. The importance of the latter reactions was further confirmed by plasma sampling mass spectrometry showing a double peak structure for Zn ions: a low-energy component ascribed to thermalized ions created in the gas phase (by direct electron impact and by Penning ionization) and a high-energy tail due to ions ejected from the target and reaching quasi-collisionlessly the substrate surface.

  18. CD-3: Crystalline Rock - Basement | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:EzfeedflagBiomassSustainable andBucoda,BurkeNebraska: EnergyByronTechnologiesCD-2:

  19. Thermal conductivity of self-assembled nano-structured ZnO bulk ceramics

    SciTech Connect (OSTI)

    Zhao, Yu [Bio-Inspired Materials and Devices Laboraory (BMDL); Yan, Yongke [Bio-Inspired Materials and Devices Laboraory (BMDL); Kumar, Ashok [Bio-Inspired Materials and Devices Laboraory (BMDL); Wang, Hsin [ORNL; Porter, Wallace D [ORNL

    2012-01-01T23:59:59.000Z

    In this study, we describe the changes in thermal conductivity behavior of ZnO-Al micro- and nano-two-phase self-assembled composites with varying grain sizes. The reduction in thermal conductivity values of micro-composites was limited to {approx}15% for ZnO-4% Al. However, nano-composites exhibited large reduction, by a factor of about three, due to uniform distribution of nano-precipitates (ZnAl2O4) and large grain boundary area. Interestingly, the micro-composites revealed continuous decrease in thermal conductivity with increase in Al substitution while the nano-composites exhibited the lowest magnitudes for 2% Al concentration. Raman spectra indicated that phonon confinement in ZnO-Al nano-composites causes drastic decrease in the value of thermal conductivity.

  20. Optimizing the Power Output of a ZnO Photocell by Piezopotential

    E-Print Network [OSTI]

    Wang, Zhong L.

    properties of ZnO make it an ideal choice for applications in nanogenerators10 13 for converting mechanical together with the thermionic emission theory has explained the four kinds of relationships observed

  1. Fabrication and Luminescence of ZnS:Mn2+ Nanoflowers. | EMSL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of ZnS:Mn2+ nanoparticles are prepared and characterized. The configurations of these fractal structures are very sensitive to both the pH values of the particle solutions from...

  2. The effect of PdZn particle size on reverse-water-gas-shift reaction...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    RWGS activity is consistent with that previously observed for the steam reforming of methanol, i.e., higher CO selectivity on smaller PdZn particles. Thus, RWGS has been...

  3. Synthesis and Luminescence of ZnMgS:Mn2+ Nanoparticles. | EMSL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    followed by a post-annealing process, thus showing the features of less complexity, low cost, and easy incorporation of dopants. In comparison with the emission of ZnS:Mn2+...

  4. Development of ZnO Based Light Emitting Diodes and Laser Diodes

    E-Print Network [OSTI]

    Kong, Jieying

    2012-01-01T23:59:59.000Z

    E. Fred Schubert, Light-Emitting Diodes, New York (2006) [8]ZnO homojunction light emitting diode 3. 1. Motivation ofAlGaAs red light-emitting diodes, in: G.B. Stringfellow, M.

  5. Synthesis of ZnO decorated graphene nanocomposite for enhanced photocatalytic properties

    SciTech Connect (OSTI)

    Gayathri, S.; Jayabal, P. [Department of Laser Studies, School of Physics, Madurai Kamaraj University, Madurai 625021, Tamilnadu (India); Kottaisamy, M. [Department of Chemistry, Thiagarajar College of Engineering, Madurai 625014, Tamilnadu (India); Ramakrishnan, V., E-mail: vr.optics1@gmail.com [Department of Laser Studies, School of Physics, Madurai Kamaraj University, Madurai 625021, Tamilnadu (India); Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram 695016, Kerala (India)

    2014-05-07T23:59:59.000Z

    Zinc oxide/Graphene (GZ) composites with different concentrations of ZnO were successfully synthesized through simple chemical precipitation method. The X-ray diffraction pattern and the micro-Raman spectroscopic technique revealed the formation of GZ composite, and the energy dispersive X-ray spectrometry analysis showed the purity of the prepared samples. The ZnO nanoparticles decorated graphene sheets were clearly visible in the field emission scanning electron micrograph. Raman mapping was employed to analyze the homogeneity of the prepared samples. The diffuse-reflectance spectra clearly indicated that the formation of GZ composites promoted the absorption in the visible region also. The photocatalytic activity of ZnO and GZ composites was studied by the photodegradation of Methylene blue dye. The results revealed that the GZ composites exhibited a higher photocatalytic activity than pristine ZnO. Hence, we proposed a simple wet chemical method to synthesize GZ composite and its application on photocatalysis was demonstrated.

  6. Electrodeposition of ZnO Nanorods in the Presence of Metal Ions...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    B Wutzke, and RF Koenenkamp.2009."Electrodeposition of ZnO Nanorods in the Presence of Metal Ions."Materials Letters 63(9-10):736-738. doi:10.1016j.matlet.2008.12.037 Authors:...

  7. Soil and Mold Influences on Fe and Zn Concentrations of Sorghum Grain in Mali, West Africa

    E-Print Network [OSTI]

    Verbree, Cheryl

    2012-10-19T23:59:59.000Z

    Iron (Fe) and zinc (Zn) deficiencies affect an estimated 3 billion people worldwide and are linked with cognitive and physical impairments, maternal and child mortality rates, and decreased adult work activity. To combat this "hidden" hunger, plant...

  8. The Effect of Zn Addition on the Oxidation State of Cobalt in...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    effect of Zn promotion on the activity and selectivity of CoZrO2 catalysts for ethanol steam reforming was investigated. The catalysts were synthesized by incipient wetness...

  9. Inhibition Mechanisms of Zn Precipitation on Aluminum Oxide by Glyphosate: A 31

    E-Print Network [OSTI]

    Sparks, Donald L.

    and crops, and becomes a potential threat to human beings via the food chain.5 In soils, excessive Zn can, and an -Ni hydroxide formed instead due to the complexation of Al by these two organic ligands. Likewise

  10. Spinel ferrite nanocrystals embedded inside ZnO: magnetic, electronic and magneto-transport properties

    E-Print Network [OSTI]

    Zhou, Shengqiang

    2010-01-01T23:59:59.000Z

    Spinel ferrite nanocrystals embedded inside ZnO: magnetic,paper we show that spinel ferrite nanocrystals (NiFe 2 O 4 ,annealing. The two kinds of ferrites show di?erent magnetic

  11. Polymeric precursor derived nanocrystalline ZnO thin films using EDTA as chelating agent

    E-Print Network [OSTI]

    Mohanty, Saraju P.

    properties, ZnO has plausible electro-optical applications, such as, solar cells [1, 2], light- emitting diodes [3, 4], UV lasers [5], thin film transistors [6,7], and UV photodetectors [8]. Besides

  12. Colloidal Nanocrystals of Wurtzite Zn1-xCoxO (0 ? x ? 1)...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Zn1-xCoxO (0 ? x ? 1): Models of Spinodal Decomposition in an Oxide Diluted Magnetic Semiconductor."Chemistry of Materials 20(22):7107-7116. doi:10.1021cm802280g Authors: MA...

  13. A New Cell-Permeable Fluorescent Probe for Zn2+ Grant K. Walkup,

    E-Print Network [OSTI]

    Tsien, Roger Y.

    of Chemistry Massachusetts Institute of Technology Cambridge, Massachusetts, 02139 ReceiVed March 10, 2000 Re gene expression,3 apoptosis,4 enzyme regulation,5 and neurotransmission6,7 suggests that Zn2+ may

  14. Zn Speciation in the Organic Horizon of a Contaminated Soil by

    E-Print Network [OSTI]

    . Such an organic topsoil, located downwind of an active zinc smelter and extremely rich in Zn (2%, dry weight the transfer of metals to the drinking water and to the food chain. The zinc smelter of Auby (Nord, France) has

  15. Terahertz Dielectric Properties and Low-Frequency Phonon Resonances of ZnO Nanostructures

    E-Print Network [OSTI]

    spectral region, and therefore it can be used as the transparent conductive electrodes in solar cells and flat panel displays.10 Additionally, surface acoustic wave filters made from ZnO films have been used

  16. Residue Ionization in LpxC Directly Observed by 67Zn NMR Spectroscopy...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Abstract: The pH dependence of the 67Zn NMR spectroscopy has been measured for both wild type (WT) and the H265A mutant of LpxC, each in the resting state – absence of...

  17. Electronic Structure of ZnO:GaN Compounds: Asymmetric Bandgap Engineering

    SciTech Connect (OSTI)

    Huda, M. N.; Yan, Y.; Wei, S. H.; Al-Jassim, M. M.

    2008-11-01T23:59:59.000Z

    ZnO and GaN have a type-II band offset. The incorporation of one compound into the other would lead to a reduced bandgap as compared to that of either ZnO or GaN. Our density-functional theory calculation reveals an asymmetric bandgap reduction in this nonisovalent system; i.e., incorporating GaN in a ZnO host results in a much more effective bandgap reduction than incorporating ZnO in a GaN host. We further find that the random-alloy system is more favorable than the superlattice system in terms of light absorption in the longer-wavelength regions. Our results suggest that the wave-function localization at the band edges plays an important role in how to choose the host material and dopant for effective bandgap engineering through semiconductor compound alloying.

  18. Ferromagnetism in Ti-Doped ZnO Nanoclusters above Room Temperature...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    increase of temperature. Citation: Antony J, S Pendyala, DE McCready, MH Engelhard, D Meyer, AM Sharma, and Y Qiang.2006."Ferromagnetism in Ti-Doped ZnO Nanoclusters above Room...

  19. ZnO nanowires on glass via chemical routes: A prospective photocatalyst for indoors applications

    E-Print Network [OSTI]

    O:Al Seed layer Photocatalysis Stearic acid A B S T R A C T Versatile ZnO nanowires with controlled applications. ã 2014 Elsevier Ltd. All rights reserved. Introduction Heterogeneous photocatalysis is attracting

  20. Multianalyte biosensor based on pH-sensitive ZnO electrolyte–insulator–semiconductor structures

    SciTech Connect (OSTI)

    Haur Kao, Chyuan; Chun Liu, Che; Ueng, Herng-Yih [Department of Electronic Engineering, Chang Gung University, Kwei-Shan, Tao-Yuan 333, Taiwan (China); Chen, Hsiang, E-mail: hchen@ncnu.edu.tw; Cheng Chu, Yu; Jie Chen, Yu [Department of Applied Materials and Optoelectronic Engineering, National Chi Nan University, Puli, Nantou 545, Taiwan (China); Ling Lee, Ming; Ming Chang, Kow [Department of Electronic Engineering, National Chiao Tung University, Hsin-Chu 300, Taiwan (China)

    2014-05-14T23:59:59.000Z

    Multianalyte electrolyte–insulator–semiconductor (EIS) sensors with a ZnO sensing membrane annealed on silicon substrate for use in pH sensing were fabricated. Material analyses were conducted using X-ray diffraction and atomic force microscopy to identify optimal treatment conditions. Sensing performance for various ions of Na{sup +}, K{sup +}, urea, and glucose was also tested. Results indicate that an EIS sensor with a ZnO membrane annealed at 600?°C exhibited good performance with high sensitivity and a low drift rate compared with all other reported ZnO-based pH sensors. Furthermore, based on well-established pH sensing properties, pH-ion-sensitive field-effect transistor sensors have also been developed for use in detecting urea and glucose ions. ZnO-based EIS sensors show promise for future industrial biosensing applications.

  1. Single-valley quantum Hall ferromagnet in a dilute MgxZn1-xO/ZnO strongly correlated two-dimensional electron system

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kozuka, Y.; Tsukazaki, A.; Maryenko, D.; Falson, J.; Bell, C.; Kim, M.; Hikita, Y.; Hwang, H. Y.; Kawasaki, M.

    2012-02-01T23:59:59.000Z

    We investigate the spin susceptibility (g*m*) of dilute two-dimensional (2D) electrons confined at the MgxZn1-xO/ZnO heterointerface. Magnetotransport measurements show a four-fold enhancement of g*m*, dominated by the increase in the Landé g-factor. The g-factor enhancement leads to a ferromagnetic instability of the electron gas as evidenced by sharp resistance spikes. At high magnetic field, the large g*m* leads to full spin polarization, where we found sudden increase in resistance around the filling factors of half-integer, accompanied by complete disappearance of fractional quantum Hall (QH) states. Along with its large effective mass and the high electron mobility, our result indicates that the ZnO 2D system is ideal for investigating the effect of electron correlations in the QH regime.

  2. Single-valley quantum Hall ferromagnet in a dilute MgxZn1-xO/ZnO strongly correlated two-dimensional electron system

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kozuka, Y.; Tsukazaki, A.; Maryenko, D.; Falson, J.; Bell, C.; Kim, M.; Hikita, Y.; Hwang, H. Y.; Kawasaki, M.

    2012-02-01T23:59:59.000Z

    We investigate the spin susceptibility (g*m*) of dilute two-dimensional (2D) electrons confined at the MgxZn1-xO/ZnO heterointerface. Magnetotransport measurements show a four-fold enhancement of g*m*, dominated by the increase in the Landé g-factor. The g-factor enhancement leads to a ferromagnetic instability of the electron gas as evidenced by sharp resistance spikes. At high magnetic field, the large g*m* leads to full spin polarization, where we found sudden increase in resistance around the filling factors of half-integer, accompanied by complete disappearance of fractional quantum Hall (QH) states. Along with its large effective mass and the high electron mobility, our result indicates thatmore »the ZnO 2D system is ideal for investigating the effect of electron correlations in the QH regime.« less

  3. Synthesis of highly efficient antibacterial agent Ag doped ZnO nanorods: Structural, Raman and optical properties

    SciTech Connect (OSTI)

    Jan, Tariq; Iqbal, Javed, E-mail: javed.saggu@iiu.edu.pk [Laboratory of Nanoscience and Technology, Department of Physics, International Islamic University Islamabad (Pakistan); Ismail, Muhammad [Institute of Biomedical and Genetic Engineering (IBGE), Islamabad (Pakistan); Mahmood, Arshad [Nano Devices Labs, National Institute of Lasers and Optronics, Islamabad (Pakistan)

    2014-04-21T23:59:59.000Z

    Here, synthesis, structural, morphological, Raman, optical properties and antibacterial activity of undoped and Ag doped ZnO nanorods by chemical co-precipitation technique have been reported. Structural analysis has revealed that Ag doping cannot deteriorate the structure of ZnO and wurtzite phase is maintained. Lattice constants are found to be decreased with the Ag doping. Fourier transform infrared and Raman spectroscopy also confirm the X-ray diffraction results. Scanning electron microscopy results have demonstrated the formation of ZnO nanorods with average diameter and length of 96?nm and 700?nm, respectively. Raman spectroscopy results suggest that the Ag doping enhances the number of defects in ZnO crystal. It has been found from optical study that Ag doping results in positional shift of band edge absorption peak. This is attributed to the successful incorporation of Ag dopant into ZnO host matrix. The antibacterial activity of prepared nanorods has been determined by two different methods and compared to that of undoped ZnO nanorods. Ag doped ZnO nanorods exhibit excellent antibacterial activity as compared to that of undoped ZnO nanorods. This excellent antibacterial activity may be attributed to the presence of oxygen vacancies and Zn{sup 2+} interstitial defects. Our preliminary findings suggest that Ag doped ZnO nanorods can be used externally to control the spreading of infections related with tested bacterial strains.

  4. THE THERMOELASTIC PHASE TRANSITION IN Au-Cd ALLOYS STUDIES BY ACOUSTIC EMISSION

    E-Print Network [OSTI]

    Baram, I.

    2013-01-01T23:59:59.000Z

    at. % Cd Cycle LTP +HTP Transformation LTP Transformation 3°high temperature phase (htp) to the low temperature phase (the dissipated elastic energy. The htp ~ ltp and the reverse

  5. Characterization and Analysis of CIGS and CdTE Solar Cells: December 2004 - July 2008

    SciTech Connect (OSTI)

    Sites, J. R.

    2009-01-01T23:59:59.000Z

    The work reported here embodies a device-physics approach based on careful measurement and interpretation of data from CIGS and CdTe solar cells.

  6. Metallurgical study of duplex stainless steel CD4Mcu Casting Material for Purex type nozzles

    SciTech Connect (OSTI)

    LESHIKAR, G.A.

    2003-05-08T23:59:59.000Z

    The studies presented in this document evaluate the metallurgy of Cast Grade Alloys CD4MCu and CD4MCuN (ASTM A890, Grades 1A and 1B). CD4MCu has been used as a Purex-Type nozzle casting material since the early 1960's, when it was a new and exotic material. The current metallurgical knowledge base shows addition of nitrogen to the alloy is very beneficial (CD4MCuN), and rapid cooling (water quenching) is essential to achieving the sought-after material properties.

  7. Semiconductor quantum dots enhanced graphene/CdTe heterostructure solar cells by photo-induced doping

    E-Print Network [OSTI]

    Li, Xiaoqiang; Wang, Peng; Xu, Zhijuan; Zhong, Huikai; Wu, Zhiqian; Lin, Shisheng

    2015-01-01T23:59:59.000Z

    Photo-induced doping is employed into graphene based solar cell through designing of a novel type of solar cell based on graphene/CdTe Schottky heterostructure. By coating a layer of ultrathin CdSe quantum dots onto graphene/CdTe heterostructure, the performance of the graphene/CdTe solar cell is improved by about 50%. Photo-induced doping is mainly accounted for this enhancement, as evidenced by resistance, photoluminescence and quantum efficiency measurements. This work demonstrates a general and feasible way of designing novel type of solar cells based on two dimensional materials/semiconductor heterostructures.

  8. White luminescence from CdS nanocrystals under the blue light excitation

    SciTech Connect (OSTI)

    Li, Bo; Zhang, Xiaosong, E-mail: zhangxiaosong@tjut.edu.cn; Li, Lan; Li, Mengzhen; Xu, Jianping; Hong, Yuan

    2014-06-01T23:59:59.000Z

    Trap-rich CdS nanocrystals were synthesized by employing CdSt{sub 2} and sulfur as precursors via thermal decomposition. Furthermore, X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), absorption and photoluminescence (PL) spectra were used to characterize structure, morphology and luminescence properties of CdS nanocrystals (NCs). CdS NCs have a broad emission across 500–700 nm under the excitation of blue light with 460 nm, consequently, white light can be produced by mixing broad emission from CdS NCs excited by blue light, with the remaining blue light. In addition, the broad emission generation is closely and inseparably related to surface defects. Moreover, LaMer model was used to explain the phenomenon that the intensity of the trap emission gradually decreases as the reaction time increases in contrast with that of the band-edge emission. - Graphical abstract: Trap-rich CdS nanocrystals were synthesized. Furthermore, white light is produced by mixing broad emission across 500–700 nm from CdS NCs excited by blue light, in combination with the remaining blue light. - Highlights: • Trap-rich CdS nanocrystals were synthesized. • CdS NCs have a broad emission across 500–700 nm under the excitation of blue light. • White light can be produced by mixing broad emission with the remaining blue light.

  9. Thin-film polycrystalline n-ZnO/p-CuO heterojunction

    SciTech Connect (OSTI)

    Lisitski, O. L.; Kumekov, M. E.; Kumekov, S. E. [Satpaev Kazakh National Technical University (Kazakhstan)], E-mail: skumekov@mail.ru; Terukov, E. I. [Russian Academy of Sciences, Ioffe Physicotechnical Institute (Russian Federation)

    2009-06-15T23:59:59.000Z

    Results of X-ray diffraction and spectral-optical studies of n-ZnO and p-CuO films deposited by gas-discharge sputtering with subsequent annealing are presented. It is shown that, despite the difference in the crystal systems, the polycrystallinity of n-ZnO and p-CuO films enables fabrication of a heterojunction from this pair of materials.

  10. Low-temperature aqueous-phase reforming of ethanol on bimetallic PdZn catalysts

    SciTech Connect (OSTI)

    Xiong, Haifeng; DelaRiva, Andrew; Wang, Yong; Dayte, Abhaya

    2015-01-01T23:59:59.000Z

    Bimetallic PdZn catalysts supported on carbon black (CB) and carbon nanotubes (CNTs) were found to be selective for CO-free H-2 production from ethanol at low temperature (250 degrees C). On Pd, the H-2 yield was low (similar to 0.3 mol H-2/mol ethanol reacted) and the CH4/CO2 ratio was high (similar to 1.7). Addition of Zn to Pd formed the intermetallic PdZn beta phase (atomic ratio of Zn to Pd is 1) with increased H-2 yield (similar to 1.9 mol H-2/mol ethanol reacted) and CH4/CO2 ratio of <1. The higher H-2 yield and low CH4 formation was related to the improved dehydrogenation activity of the L1(0) PdZn beta phase. The TOF increased with particle size and the CNTs provided the most active and selective catalysts, which may be ascribed to pore-confinement effects. Furthermore, no significant changes in either the supports or the PdZn beta particles was found after aqueous-phase reforming (APR) indicating that the metal nanoparticles and the carbon support are hydrothermally stable in the aqueous phase at elevated temperatures and pressures (>200 degrees C, 65 bar). No CO was detected for all the catalysts performed in aqueous-phase reaction, indicating that both monometallic Pd and bimetallic PdZn catalysts have high water-gas shift activity during APR. However, the yield of H-2 is considerably lower than the theoretical value of 6 H-2 per mole ethanol which is due to the presence of oxygenated products and methane on the PdZn catalysts.

  11. Self-assembled ultra small ZnO nanocrystals for dye-sensitized solar cell application

    SciTech Connect (OSTI)

    Patra, Astam K.; Dutta, Arghya; Bhaumik, Asim, E-mail: msab@iacs.res.in

    2014-07-01T23:59:59.000Z

    We demonstrate a facile chemical approach to produce self-assembled ultra-small mesoporous zinc oxide nanocrystals using sodium salicylate (SS) as a template under hydrothermal conditions. These ZnO nanomaterials have been successfully fabricated as a photoanode for the dye-sensitized solar cell (DSSC) in the presence of N719 dye and iodine–triiodide electrolyte. The structural features, crystallinity, purity, mesophase and morphology of the nanostructure ZnO are investigated by several characterization tools. N{sub 2} sorption analysis revealed high surface areas (203 m{sup 2} g{sup ?1}) and narrow pore size distributions (5.1–5.4 nm) for different samples. The mesoporous structure and strong photoluminescence facilitates the high dye loading at the mesoscopic void spaces and light harvesting in DSSC. By utilizing this ultra-small ZnO photoelectrode with film thickness of about 7 ?m in the DSSC with an open-circuit voltage (V{sub OC}) of 0.74 V, short-circuit current density (J{sub SC}) of 3.83 mA cm{sup ?2} and an overall power conversion efficiency of 1.12% has been achieved. - Graphical abstract: Ultra-small ZnO nanocrystals have been synthesized with sodium salicylate as a template and using it as a photoanode in a dye-sensitized solar cell 1.12% power conversion efficiency has been observed. - Highlights: • Synthesis of self-assembled ultra-small mesoporous ZnO nanocrystals by using sodium salicylate as a template. • Mesoporous ZnO materials have high BET surface areas and void space. • ZnO nanoparticles serve as a photoanode for the dye-sensitized solar cell (DSSC). • Using ZnO nanocrystals as photoelectrode power conversion efficiency of 1.12% has been achieved.

  12. Waferscale highthroughput ordered growth of vertically aligned ZnO nanowire arrays

    E-Print Network [OSTI]

    Wang, Zhong L.

    arrays on GaN substrate with different periods and sizes 2 m 3 m Figure S1. LIL-Patterned growth of ZnO NW arrays on GaN substrate with different periods and sizes of opened-holes. (a) and (b) Top-view and 45o side-view SEM images of vertically aligned ZnO NW arrays on GaN substrate with 200 nm opened

  13. Mechanical and transparent conductive properties of ZnO and Ga-doped ZnO films sputtered using electron-cyclotron-resonance plasma on polyethylene naphtalate substrates

    SciTech Connect (OSTI)

    Akazawa, Housei, E-mail: akazawa.housei@lab.ntt.co.jp [NTT Microsystem Integration Laboratories 3-1 Morinosato Wakamiya, Atsugi, Kanagawa 243-0198 (Japan)

    2014-03-15T23:59:59.000Z

    Transparent conductive ZnO and Ga-doped ZnO (GZO) films were deposited on polyethylene naphtalate (PEN) sheet substrates using electron cyclotron resonance plasma sputtering. Both ZnO and GZO films were highly adhesive to the PEN substrates without inserting an intermediate layer in the interface. When compared at the same thickness, the transparent conductive properties of GZO films on PEN substrates were only slightly inferior to those on glass substrates. However, the carrier concentration of ZnO films on PEN substrates was 1.5?times that of those on glass substrates, whereas their Hall mobility was only 60% at a thickness of 300?nm. The depth profile of elements measured by secondary ion mass spectroscopy revealed the diffusion of hydrocarbons out of the PEN substrate into the ZnO film. Hence, doped carbons may act as donors to enhance carrier concentration, and the intermixing of elements at the interface may deteriorate the crystallinity, resulting in the lower Hall mobility. When the ZnO films were thicker than 400?nm, cracks became prevalent because of the lattice mismatch strain between the film and the substrate, whereas GZO films were free of cracks. The authors investigated how rolling the films around a cylindrical pipe surface affected their conductive properties. Degraded conductivity occurred at a threshold pipe radius of 10?mm when tensile stress was applied to the film, but it occurred at a pipe radius of 5?mm when compressive stress was applied. These values are guidelines for bending actual devices fabricated on PEN substrates.

  14. Morphological and electrochemical characterization of electrodeposited Zn–Ag nanoparticle composite coatings

    SciTech Connect (OSTI)

    Punith Kumar, M.K.; Srivastava, Chandan, E-mail: csrivastava@materials.iisc.ernet.in

    2013-11-15T23:59:59.000Z

    Silver nanoparticles with an average size of 23 nm were chemically synthesized and used to fabricate Zn–Ag composite coatings. The Zn–Ag composite coatings were generated by electrodeposition method using a simple sulfate plating bath dispersed with 0.5, 1 and 1.5 g/l of Ag nanoparticles. Scanning electron microscopy, X-ray diffraction and texture co-efficient calculations revealed that Ag nanoparticles appreciably influenced the morphology, micro-structure and texture of the deposit. It was also noticed that agglomerates of Ag nanoparticles, in the case of high bath load conditions, produced defects and dislocations on the deposit surface. Ag nanoparticles altered the corrosion resistance property of Zn–Ag composite coatings as observed from Tafel polarization, electrochemical impedance analysis and an immersion test. Reduction in corrosion rate with increased charge transfer resistance was observed for Zn–Ag composite coatings when compared to a pure Zn coating. However, the particle concentration in the plating bath and their agglomeration state directly influenced the surface morphology and the subsequent corrosion behavior of the deposits. - Highlights: • Synthesis of Ag nanoparticles with an average size of 23 nm • Fabrication of Zn/nano Ag composite coating on mild steel • Composite coatings showed better corrosion resistance. • Optimization of particle concentration is necessary.

  15. Magnetic properties and loss separation in iron-silicone-MnZn ferrite soft magnetic composites

    SciTech Connect (OSTI)

    Wu, Shen; Sun, Aizhi; Xu, Wenhuan; Zou, Chao; Yang, Jun; Dong, Juan [School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing (China)

    2013-12-16T23:59:59.000Z

    This paper investigates the magnetic and structural properties of iron-based soft magnetic composites coated with silicone-MnZn ferrite hybrid. The organic silicone resin was added to improve the flexibility of the insulated iron powder and causes better adhesion between particles to increase the mechanical properties. Scanning electron microscopy and distribution maps show that the iron particle surface is covered with a thin layer of silicone-MnZn ferrite. Silicone-MnZn ferrite coated samples have higher permeability when compared with the non-magnetic silicone resin coated compacts. The real part of permeability increases by 34.18% when compared with the silicone resin coated samples at 20 kHz. In this work, a formula for calculating the total loss component by loss separation method is presented and finally the different parts of total losses are calculated. The results show that the eddy current loss coefficient is close to each other for the silicone-MnZn ferrite, silicone resin and MnZn ferrite coated samples (0.0078Zn ferrite coated sample (k{sub 2} =1.4058) in comparison with other samples.

  16. Photoelectrochemical and photosensing behaviors of hydrothermally grown ZnO nanorods

    SciTech Connect (OSTI)

    Majumder, T.; Hmar, J. J. L.; Roy, J. N.; Mondal, S. P., E-mail: suvraphy@gmail.com, E-mail: suvra.phy@nita.ac.in [Department of Physics, National Institute of Technology, Agartala 799046 (India); Debnath, K. [Department of Electronics and Communication Engineering, National Institute of Technology, Agartala 799046 (India); Gogurla, N.; Ray, S. K. [Department of Physics, Indian Institute of Technology, Kharagpur 721302 (India)

    2014-07-21T23:59:59.000Z

    ZnO nanorods have been grown on indium-tin-oxide coated glass substrates by a low cost chemical process. Current-voltage characteristics have been studied using ZnO nanorods as photoanode in an electrochemical cell. The flat band voltage shift and depletion width of ZnO nanorods/electrolyte interface have been estimated from Mott-Schottky (MS) characteristics. The electrochemical impedance measurements have been carried out to study the charge transport mechanism at the semiconductor-electrolyte interface under dark and white light (100 mW/cm{sup 2}) illumination. The doping concentration of nanorods has been extracted from MS plot. Photoresponse behavior of ZnO nanorods is found to be enhanced than seed layers with the incident of white light. Spectral dependent photovoltage of ZnO nanorods has been carried out using monochromatic light of wavelength 250–600?nm. The photopotential recovery time has been estimated for nanorods and seed layers. The stability of ZnO nanorods as a photoanode has been investigated.

  17. Sensing performances of ZnO nanostructures grown under different oxygen pressures to hydrogen

    SciTech Connect (OSTI)

    Chu, Jin; Peng, Xiaoyan [Department of Physics, University of Puerto Rico Rio Piedras, San Juan, 00936-8377 PR (United States)] [Department of Physics, University of Puerto Rico Rio Piedras, San Juan, 00936-8377 PR (United States); Wang, Zhenbo [School of Chemical Engineering and Technology, Harbin Institute of Technology, Harbin 150001 (China)] [School of Chemical Engineering and Technology, Harbin Institute of Technology, Harbin 150001 (China); Feng, Peter, E-mail: P.feng@upr.edu [Department of Physics, University of Puerto Rico Rio Piedras, San Juan, 00936-8377 PR (United States)] [Department of Physics, University of Puerto Rico Rio Piedras, San Juan, 00936-8377 PR (United States)

    2012-12-15T23:59:59.000Z

    Graphical abstract: Display Omitted Highlights: ? Surface morphology depends on the oxygen pressure. ? Structural degradation was observed for the ZnO samples when oxygen pressure was overhigh. ? The sensitivity of the ZnO-based sensors increase with grown oxygen pressure. -- Abstract: For extensive use in an industrialized process of individual ZnO nanostructures applied in gas sensors, a simple, inexpensive, and safe synthesis process is required. Here, nanostructured ZnO films were grown by a pulsed laser deposition technique under different oxygen pressures. Scanning electron microscopy images show nanopores, nanotips, and nanoparticles are obtained and energy dispersive X-ray spectroscopy data indicate oxygen concentration of the synthesized samples increases monotonously with oxygen pressure. The sensor based on ZnO with high oxygen concentration has high sensitivity, rapid response (9 s) and recovery (80 s) behavior to 500 ppm hydrogen below 150 °C. Experimental data indicate that high oxygen concentration effectively improves the sensing properties of nanostructured ZnO.

  18. Hierarchically Structured ZnO Nanorods-Nanosheets for Improved Quantum-Dot-Sensitized Solar Cells

    E-Print Network [OSTI]

    Cao, Guozhong

    . INTRODUCTION The establishment of low-cost and high-performance solar cells for sustainable energy sources). This hierarchical structure had two advantages in improving the power conversion efficiency (PCE) of the solar cells broadens the optical absorption of the solar cells. So far, CdS/CdSe-cosensitized QDSCs have reached power

  19. Advanced CdTe Photovoltaic Technology: September 2007 - March 2009

    SciTech Connect (OSTI)

    Barth, K.

    2011-05-01T23:59:59.000Z

    During the last eighteen months, Abound Solar (formerly AVA Solar) has enjoyed significant success under the SAI program. During this time, a fully automated manufacturing line has been developed, fabricated and commissioned in Longmont, Colorado. The facility is fully integrated, converting glass and semiconductor materials into complete modules beneath its roof. At capacity, a glass panel will enter the factory every 10 seconds and emerge as a completed module two hours later. This facility is currently undergoing trials in preparation for large volume production of 120 x 60 cm thin film CdTe modules. Preceding the development of the large volume manufacturing capability, Abound Solar demonstrated long duration processing with excellent materials utilization for the manufacture of high efficiency 42 cm square modules. Abound Solar prototype modules have been measured with over 9% aperture area efficiency by NREL. Abound Solar demonstrated the ability to produce modules at industry leading low costs to NREL representatives. Costing models show manufacturing costs below $1/Watt and capital equipment costs below $1.50 per watt of annual manufacturing capacity. Under this SAI program, Abound Solar supported a significant research and development program at Colorado State University. The CSU team continues to make progress on device and materials analysis. Modeling for increased device performance and the effects of processing conditions on properties of CdTe PV were investigated.

  20. Magneto acoustical emission in nanocrystalline Mn–Zn ferrites

    SciTech Connect (OSTI)

    Praveena, K., E-mail: praveenaou@gmail.com [Materials Research Centre, Indian Institute of Science, Bangalore 560012 (India); Department of Physics, Osmania University, Hyderabad 500007 (India); Murthty, S.R. [Department of Physics, Osmania University, Hyderabad 500007 (India)

    2013-11-15T23:59:59.000Z

    Graphical abstract: Mn{sub 0.4}Zn{sub 0.6}Fe{sub 2}O{sub 4} powders were prepared by microwave hydrothermal method. The powders were characterized by X-ray diffraction, transmission electron microscope. The powders were sintered at different temperatures 400, 500, 600, 700, 800 and 900 °C/30 min using microwave sintering method. The grain size was estimated by scanning electron microscope. The room temperature dielectric and magnetic properties were studied in the frequency range (100 kHz–1.8 GHz). The magnetization properties were measured upto 1.5 T. The acoustic emission has been measured along the hysteresis loops from 80 K to Curie temperature. It is found that the magneto-acoustic emission (MAE) activity along hysteresis loop is proportional to the hysteresis losses during the same loop. This law has been verified on series of polycrystalline ferrites and found that the law is valid whatever the composition, the grain size and temperature. It is also found that the domain wall creation/or annihilation processes are the origin of the MAE. - Highlights: • The AE been measured along the hysteresis loops from 80 K to Curie temperature. • The MAE activity along hysteresis loop is proportional to P{sub h} during the same loop. • It is found that the domain wall creation/or annihilation processes are the origin of the MAE. - Abstract: Mn{sub 0.4}Zn{sub 0.6}Fe{sub 2}O{sub 4} powders were prepared by microwave hydrothermal method. The powders were characterized by X-ray diffraction, transmission electron microscope. The powders were sintered at different temperatures 400, 500, 600, 700, 800 and 900 °C/30 min using microwave sintering method. The grain size was estimated by scanning electron microscope. The room temperature dielectric and magnetic properties were studied in the frequency range (100 kHz–1.8 GHz). The magnetization properties were measured upto 1.5 T. The acoustic emission has been measured along the hysteresis loops from 80 K to Curie temperature. It is found that the magneto-acoustic emission (MAE) activity along hysteresis loop is proportional to the hysteresis losses during the same loop. This law has been verified on series of polycrystalline ferrites and found that the law is valid whatever the composition, the grain size and temperature. It is also found that the domain wall creation/or annihilation processes are the origin of the MAE.

  1. ZnO-Al2O3 and ZnO-TiO2 Core-Shell Nanowire Dye-Sensitized Solar Cells Matt Law,, Lori E. Greene,, Aleksandra Radenovic, Tevye Kuykendall,,

    E-Print Network [OSTI]

    Yang, Peidong

    ZnO-Al2O3 and ZnO-TiO2 Core-Shell Nanowire Dye-Sensitized Solar Cells Matt Law,,§ Lori E. Greene the construction and performance of dye-sensitized solar cells (DSCs) based on arrays of ZnO nanowires coated loadings through an increase in nanowire array surface area. Introduction Dye-sensitized solar cells (DSCs

  2. Aging and annealing effects on properties of Ag-N dual-acceptor doped ZnO thin films

    SciTech Connect (OSTI)

    Swapna, R.; Amiruddin, R.; Santhosh Kumar, M. C. [Advanced Materials Laboratory, Department of Physics, National Institute of Technology, Tiruchirappalli -620 015 (India)

    2013-02-05T23:59:59.000Z

    Ag-N dual acceptor doping into ZnO has been proposed to realize p-ZnO thin film of different concentrations (1, 2 and 4 at.%) by spray pyrolysis at 623 K and then 4 at.% films annealed at 673 K and 723 K for 1 hr. X-ray diffraction studies reveal that all the films are preferentially oriented along (002) plane. Energy dispersive spectroscopy (EDS) confirms the presence of Ag and N in 2 at.% ZnO:(Ag, N) film. Hall measurement shows that 4 at.% ZnO:(Ag, N) film achieved minimum resistivity with high hole concentration. The p-type conductivity of the ZnO:(Ag, N) films is retained even after 180 days. Photoluminescence (PL) spectra of ZnO:(Ag, N) films show low density of native defects.

  3. Low background detector with enriched 116CdWO4 crystal scintillators to search for double beta decay of 116Cd

    E-Print Network [OSTI]

    Barabash, A S; Bernabei, R; Boiko, R S; Cappella, F; Caracciolo, V; Chernyak, D M; Cerulli, R; Danevich, F A; Di Vacri, M L; Dossovitskiy, A E; Galashov, E N; Incicchitti, A; Kobychev, V V; Konovalov, S I; Kovtun, G P; Kudovbenko, V M; Laubenstein, M; Mikhlin, A L; Nisi, S; Poda, D V; Podviyanuk, R B; Polischuk, O G; Shcherban, A P; Shlegel, V N; Solopikhin, D A; Stenin, Yu G; Tretyak, V I; Umatov, V I; Vasiliev, Ya V; Virich, V D

    2011-01-01T23:59:59.000Z

    A cadmium tungstate crystal boule enriched in $^{116}$Cd to 82% with mass of 1868 g was grown by the low-thermal-gradient Czochralski technique. The isotopic composition of cadmium and the trace contamination of the crystal were estimated by High Resolution Inductively Coupled Plasma Mass-Spectrometry. The crystal scintillators produced from the boule were subjected to characterization that included measurements of transmittance and energy resolution. A low background scintillation detector with two $^{116}$CdWO$_4$ crystal scintillators (586 g and 589 g) was developed. The detector was running over 1727 h deep underground at the Gran Sasso National Laboratories of the INFN (Italy), which allowed to estimate the radioactive contamination of the enriched crystal scintillators. The radiopurity of a third $^{116}$CdWO$_4$ sample (326 g) was tested with the help of ultra-low background high purity germanium $\\gamma$ detector. Monte Carlo simulations of double $\\beta$ processes in $^{116}$Cd were used to estimate ...

  4. Fabrication of ZnO photonic crystals by nanosphere lithography using inductively coupled-plasma reactive ion etching with CH{sub 4}/H{sub 2}/Ar plasma on the ZnO/GaN heterojunction light emitting diodes

    SciTech Connect (OSTI)

    Chen, Shr-Jia; Chang, Chun-Ming; Kao, Jiann-Shiun; Chen, Fu-Rong; Tsai, Chuen-Horng [Engineering and System Science, National Tsing Hua University, Hsinchu, 30013 Taiwan (China); Instrument Technology Research Center, National Applied Research Laboratories, Hsinchu, 300 Taiwan (China); Engineering and System Science, National Tsing Hua University, Hsinchu, 30013 Taiwan (China)

    2010-07-15T23:59:59.000Z

    This article reports fabrication of n-ZnO photonic crystal/p-GaN light emitting diode (LED) by nanosphere lithography to further booster the light efficiency. In this article, the fabrication of ZnO photonic crystals is carried out by nanosphere lithography using inductively coupled plasma reactive ion etching with CH{sub 4}/H{sub 2}/Ar plasma on the n-ZnO/p-GaN heterojunction LEDs. The CH{sub 4}/H{sub 2}/Ar mixed gas gives high etching rate of n-ZnO film, which yields a better surface morphology and results less plasma-induced damages of the n-ZnO film. Optimal ZnO lattice parameters of 200 nm and air fill factor from 0.35 to 0.65 were obtained from fitting the spectrum of n-ZnO/p-GaN LED using a MATLAB code. In this article, we will show our recent result that a ZnO photonic crystal cylinder has been fabricated using polystyrene nanosphere mask with lattice parameter of 200 nm and radius of hole around 70 nm. Surface morphology of ZnO photonic crystal was examined by scanning electron microscope.

  5. In vitro cytotoxicity tests of ZnO?Bi{sub 2}O{sub 3}?Mn{sub 2}O{sub 3}-based varistor fabricated from ZnO micro and nanoparticle powders on L929 mouse cells

    SciTech Connect (OSTI)

    Sendi, Rabab Khalid, E-mail: last-name3@hotmail.com, E-mail: shahromx@hotmail.com, E-mail: ameerah7@hotmail.com; Mahmud, Shahrom, E-mail: last-name3@hotmail.com, E-mail: shahromx@hotmail.com, E-mail: ameerah7@hotmail.com; Munshi, Ayman, E-mail: last-name3@hotmail.com, E-mail: shahromx@hotmail.com, E-mail: ameerah7@hotmail.com [Nano-optoelectronics Research and Technology Laboratory (N.O.R.), School of Physics, Universiti Sains Malaysia, 11800, Penang (Malaysia); Seeni, Azman, E-mail: azanseeni@gmail.com [Advanced Medical and Dental Institute (AMDI), Universiti Sains Malaysia, 13200, Bertam, Pulau Pinang (Malaysia)

    2014-10-24T23:59:59.000Z

    The present study investigated the cytotoxicity of ZnO?Bi{sub 2}O{sub 3}?Mn{sub 2}O{sub 3}-varistors. To this effect, ZnO?Bi{sub 2}O{sub 3}?Mn{sub 2}O{sub 3} varistors fabricated from ZnO micro-and nanoparticle powders are prepared via conventional ceramic processing method. The effects of ZnO particle size on the properties of ZnO varistors are also investigated. The strong solid-state reaction during sintering may be attributed to the high surface area of the 20 nm ZnO nanoparticles that promote strong surface reaction. The intensity of XRD peaks reflected the high degree of crystallinity of the ZnO nanoparticles. However, the width of the peaks in case of ZnO nanoparticles has increased due to the quantum size effect. The cytotoxicity evaluation of ZnO varistor was conducted on mouse connective tissue fibroblast cells (L929) using Trypan Blue Exclusion Assay analysis. The results show that the four types of varistor samples lead to cellular mitochondrial dysfunction, morphological modifications and apoptosis at the various concentration range and the toxic effects are obviously displayed in high concentration samples. 20nm-VDR is the most toxic materials followed by 40nm-VDR, P8-VDR, and W4-VDR in a descending order.

  6. Europium substitution into intermetallic phases grown in Ca/Zn flux

    SciTech Connect (OSTI)

    Stojanovic, Milorad [Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL 32306-4390 (United States); Latturner, Susan E., E-mail: latturne@chem.fsu.ed [Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL 32306-4390 (United States)

    2009-08-15T23:59:59.000Z

    Replacement of calcium with europium in the phases Ca{sub 21}Ni{sub 2}Zn{sub 36} and CaNi{sub 2}Zn{sub 3} was attempted to explore the possibility of substitution in metal flux reactions and potential magnetic interactions between closely spaced Eu{sup 2+} ions. Limited substitution occurs when Eu is added to the reaction of nickel in a Ca/Zn flux mixture, up to stoichiometries of Eu{sub 5.8(3)}Ca{sub 15.2(3)}Ni{sub 2}Zn{sub 36} and Eu{sub 0.42(8)}Ca{sub 0.58(8)}Ni{sub 2}Zn{sub 3}. Structural characterization and magnetic susceptibility studies on Eu{sub x}Ca{sub 21-x}Ni{sub 2}Zn{sub 36} phases indicate that the Eu and Ca ions do not form an even solid solution on their sites, but instead segregate in separate regions of the crystals. The europium-rich regions of the samples order ferromagnetically, with T{sub C} dependent on the size of the clusters. If the concentration of Eu in the flux is raised above 20 mol%, a new compound Eu{sub 1.63(1)}Ca{sub 1.37(1)}Ni{sub 2}Zn{sub 3} (Cmcm, a=4.1150(5) A, b=16.948(2) A, c=10.302(1) A, Z=4, R{sub 1}=0.0396) is produced. - Graphical abstract: Exploration of europium substitution into intermetallic compounds grown in Ca/Zn flux has yielded analogs of Eu{sub x}Ca{sub 21-x}Ni{sub 2}Zn{sub 36} with unusual magnetic properties due to segregation of europium in the crystals; high concentrations of Eu in the flux trigger the growth of Eu{sub 1.63(1)}Ca{sub 1.37(1)}Ni{sub 2}Zn{sub 3} with a new structure type.

  7. Optical and morphological properties of MBE grown wurtzite CdxZn1xO thin films

    E-Print Network [OSTI]

    Kik, Pieter

    Optical and morphological properties of MBE grown wurtzite CdxZn1ÀxO thin films J.W. Mares a , F January 2007 Abstract Wurtzite CdxZn1ÀxO epilayers with cadmium concentrations ranging from x = 0.02 to 0 wurtzite CdxZn1ÀxO compounds for visible light emission in future optoelectronic devices. Ó 2006 Elsevier B

  8. Hybrid structure of polyaniline/ZnO nanograss and its application in dye-sensitized solar cell with performance improvement

    SciTech Connect (OSTI)

    Zhu Shibu; Wei Wei; Chen Xiangnan [Key Laboratory of Advanced Technologies of Materials (Ministry of Education), School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, 610031 (China); Jiang Man, E-mail: jiangman1021@163.com [Key Laboratory of Advanced Technologies of Materials (Ministry of Education), School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, 610031 (China); Zhou Zuowan, E-mail: zwzhou@at-c.net [Key Laboratory of Advanced Technologies of Materials (Ministry of Education), School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, 610031 (China)

    2012-06-15T23:59:59.000Z

    Polyaniline (PANI) hybridized ZnO photoanode for dye-sensitized solar cell (DSSC) was primarily prepared via a two-step process which involved hydrothermal growth of ZnO nanograss on the fluorine-doped tin oxide (FTO) substrate and subsequently chemisorption of PANI on the surfaces of the ZnO nanorods. The PANI hybridized ZnO nanograss films were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectra (FT-IR), and the results indicated that there were chemical interactions between PANI and ZnO. Both pure ZnO nanograss and PANI hybridized ZnO nanograss were applied to DSSC. The results of photoelectrochemical measurement showed that the photocurrent density of PANI (100 mg/L) hybridized ZnO nanograss photoanode was significantly enhanced, and the overall light-conversion efficiency increased by 60%. The electrochemical impedance spectra (EIS) displayed that the electron densities in photoanodes of PANI hybridized ZnO nanograss were larger than that in pure ZnO nanograss. This is ascribed to more effective charge separation and faster interfacial charge transferring occurred in the hybrid photoanode. - Graphical abstract: Operational principle of the DSSC: the introduced hybridizing PANI layer performs effective charge separation and faster interfacial charge transferring. Highlights: Black-Right-Pointing-Pointer PANI/ZnO nanograss hybrid materials as photoanode in Dye-sensitized solar cell. Black-Right-Pointing-Pointer Photoelectric conversion efficiency after hybridization was enhanced by 60%. Black-Right-Pointing-Pointer PANI hybridizing ZnO nanograss induced a rapid charge separation.

  9. Photovoltaic cells fabricated by electrophoretic deposition of CdSe nanocrystals

    E-Print Network [OSTI]

    Smith, Nathanael J.

    Photovoltaic cells fabricated by electrophoretic deposition of CdSe nanocrystals Nathanael J. Smith Electrophoretic deposition was used to deposit CdSe nanocrystals on TiO2 for use in photovoltaic cells formed. A solar cell constructed using electrophoretic deposition exhibited a photovoltaic response from

  10. The role of Erk MAPK pathway in CD4 T cell proliferation and differentiation

    E-Print Network [OSTI]

    Chang, Chiung-Fang

    2011-01-01T23:59:59.000Z

    B. (2010). Key role of ERK pathway signaling in lupus.and Hedrick, S.M. The role of Erk MAPK pathway in CD4 T cellTHE DISSERTATION The role of Erk MAPK pathway in CD4 T cell

  11. STRUCTURE DE BANDES DES CRISTAUX DE TYPE WURTZITE TRANSITIONS OPTIQUES INTRINSQUES DANS LE CdS.

    E-Print Network [OSTI]

    Boyer, Edmond

    825. STRUCTURE DE BANDES DES CRISTAUX DE TYPE WURTZITE TRANSITIONS OPTIQUES INTRINSÈQUES DANS LE Cd Brillouin pour des cristaux de type wurtzite est déduite des considérations de la théorie des groupes. Le Cd d'excitons. Un second article traite le problème de l'exciton dans les cristaux de type wurtzite

  12. Oxygen Incorporation During Fabrication of Substrate CdTe Photovoltaic Devices: Preprint

    SciTech Connect (OSTI)

    Duenow, J. N.; Dhere, R. G.; Kuciauskas, D.; Li, J. V.; Pankow, J. W.; DeHart, C. M.; Gessert, T. A.

    2012-06-01T23:59:59.000Z

    Recently, CdTe photovoltaic (PV) devices fabricated in the nonstandard substrate configuration have attracted increasing interest because of their potential compatibility with flexible substrates such as metal foils and polymer films. This compatibility could lead to the suitability of CdTe for roll-to-roll processing and building-integrated PV. Currently, however, the efficiencies of substrate CdTe devices reported in the literature are significantly lower ({approx}6%-8%) than those of high-performance superstrate devices ({approx}17%) because of significantly lower open-circuit voltage (Voc) and fill factor (FF). In our recent device development efforts, we have found that processing parameters required to fabricate high-efficiency substrate CdTe PV devices differ from those necessary for traditional superstrate CdTe devices. Here, we investigate how oxygen incorporation in the CdTe deposition, CdCl2 heat treatment, CdS deposition, and post-deposition heat treatment affect device characteristics through their effects on the junction. By adjusting whether oxygen is incorporated during these processing steps, we have achieved Voc values greater than 860 mV and efficiencies greater than 10%.

  13. NUMERICAL MODELING OF CIGS AND CdTe SOLAR CELLS: SETTING THE BASELINE

    E-Print Network [OSTI]

    Sites, James R.

    NUMERICAL MODELING OF CIGS AND CdTe SOLAR CELLS: SETTING THE BASELINE M. Gloeckler, A important complications that are often found in experimental CIGS and CdTe solar cells. 1. INTRODUCTION Numerical modeling of polycrystalline thin-film solar cells is an important strategy to test the viability

  14. PROOF COPY 001312APL Synthesis and electronic transport studies of CdO nanoneedles

    E-Print Network [OSTI]

    Zhou, Chongwu

    in front panel displays and solar batteries.8 Among the TCO family, nanostructures based on Cd stream and the downstream of a quartz tube furnace, respectively. The substrates zone was heated up to 850 900 °C to activate the gold catalytic particles, followed by heating up the Cd source to 350 °C

  15. Accelerated Stress Testing and Diagnostic Analysis of Degradation in CdTe Solar Cells

    SciTech Connect (OSTI)

    Albin, D. S.

    2008-11-01T23:59:59.000Z

    The primary goal of this study was to ascertain the presence and types of mechanisms affecting CdS/CdTe device stability in the temperature range of 60 to 120 ..deg..C. It should be noted that the results presented were specific to cells made using the specific growth conditions described.

  16. Ion-beam treatment to prepare surfaces of p-CdTe films

    DOE Patents [OSTI]

    Gessert, Timothy A. (Conifer, CO)

    2001-01-01T23:59:59.000Z

    A method of making a low-resistance electrical contact between a p-CdTe layer and outer contact layers by ion beam processing comprising: a) placing a CdS/CdTe device into a chamber and evacuating the chamber; b) orienting the p-CdTe side of the CdS/CdTe layer so that it faces apparatus capable of generating Ar atoms and ions of preferred energy and directionality; c) introducing Ar and igniting the area of apparatus capable of generating Ar atoms and ions of preferred energy and directionality in a manner so that during ion exposure, the source-to-substrate distance is maintained such that it is less than the mean-free path or diffusion length of the Ar atoms and ions at the vacuum pressure; d) allowing exposure of the p-CdTe side of the device to said ion beam for a period less than about 5 minutes; and e) imparting movement to the substrate to control the real uniformity of the ion-beam exposure on the p-CdTe side of the device.

  17. THROUGH-THE-GLASS SPECTROSCOPIC ELLIPSOMETRY OF CdTe SOLAR CELLS

    E-Print Network [OSTI]

    Rockett, Angus

    THROUGH-THE-GLASS SPECTROSCOPIC ELLIPSOMETRY OF CdTe SOLAR CELLS Jie Chen 1 , Jian Li 1 , Courtney of the optical structure of CdTe solar cells on transparent conducting oxide (TCO) coated glass superstrates. SE components from the coated glass before solar cell fabrication. A step-by-step fitting procedure identifies

  18. IMPROVEMENTS IN THE MANUFACTURE OF CdTe GAMMA RAY DETECTORS

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    been made in the quality of chlorine-doped CdTe crystals manufactured by the traveling heater method discussing the process modifications studied in the program, the steps (formation, purification, and doping. - The reaction step of Cd and Te begins when the two elements are melted in the quartz ampule at temperatures

  19. Strain relaxation by dislocation glide in ZnO/ZnMgO core-shell nanowires G. Perillat-Merceroz,1, 2, a)

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    deposited on ZnO nanowires. Strain along the a and c axes of the wurtzite structure is relaxed through have been calculated for cubic17 and wurtzite16 structures. For wurtzite mate- rials, the strain energy of wurtzite InAs/GaAs core-shell nanowires.18,19 How- ever, there are no indications of dislocations threading

  20. Band alignment of epitaxial ZnS/Zn3P2 heterojunctions Jeffrey P. Bosco, Steven B. Demers, Gregory M. Kimball, Nathan S. Lewis, and Harry A. Atwater

    E-Print Network [OSTI]

    Kimball, Gregory

    ) Determination of the deep donor-like interface state density distribution in metal/Al2O3/n-GaN structures from phosphide (a- Zn3P2) has a nearly optimal, direct band gap of 1.50 eV and a high visible-light absorption

  1. The Effect Of ZnO Addition On Co/C Catalyst For Vapor And Aqueous Phase Reforming Of Ethanol

    SciTech Connect (OSTI)

    Davidson, Stephen; Sun, Junming; Hong, Yongchun; Karim, Ayman M.; Datye, Abhaya K.; Wang, Yong

    2014-02-05T23:59:59.000Z

    The effect of ZnO addition on the oxidation behavior of Co along with catalytic performance in vapor and aqueous phase reforming of ethanol were investigated on Co supported on carbon black (XC-72R). Carbon was selected to minimize the support interactions. Effect of ZnO addition during both vapor and aqueous phase reforming were compared at 250 °C. ZnO addition inhibited the reduction of cobalt oxides by H2 and created surface sites for H2O activation. During vapor phase reforming at 450 °C the redox of cobalt, driven by steam oxidation and H2 reduction, trended to an equilibrium of Co0/Co2+. ZnO showed no significant effect on cobalt oxidation, inferred from the minor changes of C1 product yield. Surface sites created by ZnO addition enhanced water activation and oxidation of surface carbon species, increasing CO2 selectivity. At 250 °C cobalt reduction was minimal, in situ XANES demonstrated that ZnO addition significantly facilitated oxidation of Co0 under vapor phase reforming conditions, demonstrated by lower C1 product yield. Sites introduced by ZnO addition improved the COx selectivity at 250 °C. Both Co/C and Co-ZnO/C rapidly oxidized under aqueous phase reaction conditions at 250 °C, showing negligible activity in aqueous phase reforming. This work suggests that ZnO affects the activation of H2O for Co catalysts in ethanol reforming.

  2. A comparison of ZnO films deposited on indium tin oxide and soda lime glass under identical conditions

    SciTech Connect (OSTI)

    Deka, Angshuman; Nanda, Karuna Kar [Materials Research Centre, Indian Institute of Science, Bangalore - 560012 (India)

    2013-06-15T23:59:59.000Z

    ZnO films have been grown via a vapour phase transport (VPT) on soda lime glass (SLG) and indium-tin oxide (ITO) coated glass. ZnO film on ITO had traces of Zn and C which gives them a dark appearance while that appears yellowish-white on SLG. X-ray photoelectron spectroscopy studies confirm the traces of C in the form of C-O. The photoluminescence studies reveal a prominent green luminescence band for ZnO film on ITO.

  3. The preparation of zinc silicate/ZnO particles and their use as an efficient UV absorber

    SciTech Connect (OSTI)

    Podbrscek, Peter [National Institute of Chemistry, Hajdrihova 19, SI 1000 Ljubljana (Slovenia)] [National Institute of Chemistry, Hajdrihova 19, SI 1000 Ljubljana (Slovenia); Drazic, Goran [Department for Nanostructured Materials, Jozef Stefan Institute, Jamova 39, SI 1000 Ljubljana (Slovenia)] [Department for Nanostructured Materials, Jozef Stefan Institute, Jamova 39, SI 1000 Ljubljana (Slovenia); Anzlovar, Alojz [National Institute of Chemistry, Hajdrihova 19, SI 1000 Ljubljana (Slovenia) [National Institute of Chemistry, Hajdrihova 19, SI 1000 Ljubljana (Slovenia); Center of Excellence for Polymer Materials and Technologies, Tehnoloski Park 24, 1000 Ljubljana (Slovenia); Orel, Zorica Crnjak, E-mail: zorica.crnjak.orel@ki.si [National Institute of Chemistry, Hajdrihova 19, SI 1000 Ljubljana (Slovenia); Center of Excellence for Polymer Materials and Technologies, Tehnoloski Park 24, 1000 Ljubljana (Slovenia)

    2011-11-15T23:59:59.000Z

    Highlights: {yields} We used innovative gel-route in order to prepare zinc silicate/ZnO nano-particles. {yields} Continuous reactor was efficient for synthesizing ZnO and zinc silicate/ZnO precursors. {yields} Introduction of Si into reaction mixture influenced on particle size and their photoactivity. {yields} Prepared particles are appropriate for UV absorbers in polymers. -- Abstract: The formation of zinc silicate/ZnO particles synthesized by a two-step method and their incorporation into PMMA is presented. In the first step a segmented-flow tubular reactor was used for the continuous room-temperature preparation of a zinc silicate/Zn(OH){sub 2} gel that was thermally treated after rinsing and drying in the second step. The same preparation procedure was also employed for the synthesis of pure ZnO and pure zinc silicate particles. It was found that the presence of the zinc silicate phase significantly influenced the final particle size, decreased the degree of crystallization and reduced the particles' UV absorption capabilities. The reduced photocatalytic activity of the zinc silicate/ZnO particles indicated that the majority of ZnO crystallites were formed inside the zinc silicate matrix. The nanocomposite prepared from zinc silicate/ZnO particles (0.04 wt.%) and PMMA showed high UV shielding and at the same time sufficient transmittance in the visible-light region.

  4. The role of Id2 and Id3 in memory CD8? T cells differentiation and natural killer T cell homeostasis

    E-Print Network [OSTI]

    Yang, Cliff Yang

    2012-01-01T23:59:59.000Z

    of NK1.1 + TCR? + or CD1d tetramer + NKT cells for indicatedof ?GalCer-loaded CD1d tetramer + NKT cells for indicated?GalCer-loaded CD1d tetramer, then examined for expression

  5. Growth of CdTe thin films on graphene by close-spaced sublimation method

    SciTech Connect (OSTI)

    Jung, Younghun; Yang, Gwangseok; Kim, Jihyun, E-mail: hyunhyun7@korea.ac.kr [Department of Chemical and Biological Engineering, Korea University, Seoul 136-701 (Korea, Republic of)] [Department of Chemical and Biological Engineering, Korea University, Seoul 136-701 (Korea, Republic of); Chun, Seungju; Kim, Donghwan [Department of Materials Science and Engineering, Korea University, Seoul 136-701 (Korea, Republic of)] [Department of Materials Science and Engineering, Korea University, Seoul 136-701 (Korea, Republic of)

    2013-12-02T23:59:59.000Z

    CdTe thin films grown on bi-layer graphene were demonstrated by using the close-spaced sublimation method, where CdTe was selectively grown on the graphene. The density of the CdTe domains was increased with increasing the number of the defective sites in the graphene, which was controlled by the duration of UV exposure. The CdTe growth rate on the bi-layer graphene electrodes was 400?nm/min with a bandgap energy of 1.45–1.49?eV. Scanning electron microscopy, micro-Raman spectroscopy, micro-photoluminescence, and X-ray diffraction technique were used to confirm the high quality of the CdTe thin films grown on the graphene electrodes.

  6. Fluorescence quenching of CdSe quantum dots on graphene

    SciTech Connect (OSTI)

    Guo, Xi Tao; Hua Ni, Zhen, E-mail: zhni@seu.edu.cn; Yan Nan, Hai; Hui Wang, Wen [Department of Physics and Key Laboratory of MEMS of the Ministry of Education, Southeast University, Nanjing 211189 (China)] [Department of Physics and Key Laboratory of MEMS of the Ministry of Education, Southeast University, Nanjing 211189 (China); Yan Liao, Chun [Physics Department, National Photoelectric Technology and Functional Materials and Application of Science and Technology International Cooperation Base, Northwest University, Xi'an 710069 (China)] [Physics Department, National Photoelectric Technology and Functional Materials and Application of Science and Technology International Cooperation Base, Northwest University, Xi'an 710069 (China); Zhang, Yan; Wei Zhao, Wei [Jiangsu Key Laboratory for Design and Fabrication of Micro-Nano Biomedical Instruments, School of Mechanical Engineering, Southeast University, Nanjing 211189 (China)] [Jiangsu Key Laboratory for Design and Fabrication of Micro-Nano Biomedical Instruments, School of Mechanical Engineering, Southeast University, Nanjing 211189 (China)

    2013-11-11T23:59:59.000Z

    We studied systematically the fluorescence quenching of CdSe quantum dots (QDs) on graphene and its multilayers, as well as graphene oxide (GO) and reduced graphene oxide (rGO). Raman intensity of QDs was used as a quantitatively measurement of its concentration in order to achieve a reliable quenching factor (QF). It was found that the QF of graphene (?13.1) and its multilayers is much larger than rGO (?4.4), while GO (?1.5) has the lowest quenching efficiency, which suggests that the graphitic structure is an important factor for quenching the fluorescence of QDs. It was also revealed that the QF of graphene is not strongly dependent on its thicknesses.

  7. Copper doping of ZnO crystals by transmutation of {sup 64}Zn to {sup 65}Cu: An electron paramagnetic resonance and gamma spectroscopy study

    SciTech Connect (OSTI)

    Recker, M. C.; McClory, J. W., E-mail: John.McClory@afit.edu; Holston, M. S.; Golden, E. M.; Giles, N. C. [Department of Engineering Physics, Air Force Institute of Technology, Wright-Patterson Air Force Base, Ohio 45433 (United States); Halliburton, L. E. [Department of Physics and Astronomy, West Virginia University, Morgantown, West Virginia 26506 (United States)

    2014-06-28T23:59:59.000Z

    Transmutation of {sup 64}Zn to {sup 65}Cu has been observed in a ZnO crystal irradiated with neutrons. The crystal was characterized with electron paramagnetic resonance (EPR) before and after the irradiation and with gamma spectroscopy after the irradiation. Major features in the gamma spectrum of the neutron-irradiated crystal included the primary 1115.5?keV gamma ray from the {sup 65}Zn decay and the positron annihilation peak at 511?keV. Their presence confirmed the successful transmutation of {sup 64}Zn nuclei to {sup 65}Cu. Additional direct evidence for transmutation was obtained from the EPR of Cu{sup 2+} ions (where {sup 63}Cu and {sup 65}Cu hyperfine lines are easily resolved). A spectrum from isolated Cu{sup 2+} (3d{sup 9}) ions acquired after the neutron irradiation showed only hyperfine lines from {sup 65}Cu nuclei. The absence of {sup 63}Cu lines in this Cu{sup 2+} spectrum left no doubt that the observed {sup 65}Cu signals were due to transmuted {sup 65}Cu nuclei created as a result of the neutron irradiation. Small concentrations of copper, in the form of Cu{sup +}-H complexes, were inadvertently present in our as-grown ZnO crystal. These Cu{sup +}-H complexes are not affected by the neutron irradiation, but they dissociate when a crystal is heated to 900?°C. This behavior allowed EPR to distinguish between the copper initially in the crystal and the copper subsequently produced by the neutron irradiation. In addition to transmutation, a second major effect of the neutron irradiation was the formation of zinc and oxygen vacancies by displacement. These vacancies were observed with EPR.

  8. A genome-wide regulatory network identifies key transcription factors for memory CD8[superscript +] T-cell development

    E-Print Network [OSTI]

    Hu, Guangan

    Memory CD8[superscript +] T-cell development is defined by the expression of a specific set of memory signature genes. Despite recent progress, many components of the transcriptional control of memory CD8[superscript +] ...

  9. Post-Synthesis Crystallinity Tailoring of Water-Soluble Polymer Encapsulated CdTe Nanoparticles using Rapid Thermal Annealing

    E-Print Network [OSTI]

    Post-Synthesis Crystallinity Tailoring of Water-Soluble Polymer Encapsulated CdTe Nanoparticles CdTe NPs have been demonstrated suitable for use in applications involving efficient solar cells

  10. In Situ XRD Studies of ZnO/GaN Mixtures at High Pressure and High Temperature: Synthesis of Zn-Rich (Ga1-xZnx)(N1-xOx) Photocatalysts

    SciTech Connect (OSTI)

    Chen, H.; Wang, L; Bai, J; Hanson, J; Warren, J; Muckerman, J; Fujita, E; Rodriguez, J

    2010-01-01T23:59:59.000Z

    The high-pressure, high-temperature conditions for the synthesis of Zn-rich (Ga{sub 1-x}Zn{sub x})(N{sub 1-x}O{sub x}) solid solutions from mixtures of ZnO/GaN were explored using synchrotron-based in situ time-resolved X-ray diffraction (XRD). Following a new synthetic path, (Ga{sub 1-x}Zn{sub x})(N{sub 1-x}O{sub x}) solid solutions with a Zn content up to {approx}75% were prepared for the first time. The structures of the (Ga{sub 1-x}Zn{sub x})(N{sub 1-x}O{sub x}) solid solutions were characterized by XRD and X-ray absorption fine structure (XAFS) analyses and were in excellent agreement with the predictions of density functional calculations. These materials adopt a wurtzite crystal structure with metal-N or metal-O bond distances in the range of 1.95-1.98 {angstrom}. Although the (Ga{sub 1-x}Zn{sub x})(N{sub 1-x}O{sub x}) solid solutions seem to be stable over the full range of compositions, no ideal solid solution formation was observed. In all cases, the lattice parameters were larger than those of ideal solid solutions. The variation of the lattice parameter c showed an upward double bowing curve, as was predicted by theoretical calculations. Also, no ideal behavior was observed in the electronic properties of the (Ga{sub 1-x}Zn{sub x})(N{sub 1-x}O{sub x}) solid solutions. X-ray absorption spectra at the Zn and Ga K-edges of the (Ga{sub 1-x}Zn{sub x})(N{sub 1-x}O{sub x}) systems showed significant electronic perturbations with respect to ZnO and GaN. The synthesized (Ga{sub 1-x}Zn{sub x})(N{sub 1-x}O{sub x}) solid solution with a Zn content of 50% displayed the ability to absorb visible light well above 500 nm. This material has a great potential for splitting water under visible light irradiation. The availability of (Ga{sub 1-x}Zn{sub x})(N{sub 1-x}O{sub x}) solid solutions with a high Zn content opens the door to fully explore the application of these materials in photocatalysis.

  11. In Situ XRD Studies of ZnO/GaN Mixtures at High Pressure and High Temperature: Synthesis of Zn-Rich (Ga1-xZnx)(N1-xOx) Photocatalysts

    SciTech Connect (OSTI)

    Rodriguez, J.A.; Chen, H.; Wang, L.; Bai, J.; Hanson, J.C.; Warren, J.B.; Muckerman, J.T.; Fujita, E.

    2010-02-04T23:59:59.000Z

    The high-pressure, high-temperature conditions for the synthesis of Zn-rich (Ga{sub 1-x}Zn{sub x})(N{sub 1-x}O{sub x}) solid solutions from mixtures of ZnO/GaN were explored using synchrotron-based in situ time-resolved X-ray diffraction (XRD). Following a new synthetic path, (Ga{sub 1-x}Zn{sub x})(N{sub 1-x}O{sub x}) solid solutions with a Zn content up to 75% were prepared for the first time. The structures of the (Ga{sub 1-x}Zn{sub x})(N{sub 1-x}O{sub x}) solid solutions were characterized by XRD and X-ray absorption fine structure (XAFS) analyses and were in excellent agreement with the predictions of density functional calculations. These materials adopt a wurtzite crystal structure with metal-N or metal-O bond distances in the range of 1.95-1.98 {angstrom}. Although the (Ga{sub 1-x}Zn{sub x})(N{sub 1-x}O{sub x}) solid solutions seem to be stable over the full range of compositions, no ideal solid solution formation was observed. In all cases, the lattice parameters were larger than those of ideal solid solutions. The variation of the lattice parameter c showed an upward double bowing curve, as was predicted by theoretical calculations. Also, no ideal behavior was observed in the electronic properties of the (Ga{sub 1-x}Zn{sub x})(N{sub 1-x}O{sub x}) solid solutions. X-ray absorption spectra at the Zn and Ga K-edges of the (Ga{sub 1-x}Zn{sub x})(N{sub 1-x}O{sub x}) systems showed significant electronic perturbations with respect to ZnO and GaN. The synthesized (Ga{sub 1-x}Zn{sub x})(N{sub 1-x}O{sub x}) solid solution with a Zn content of 50% displayed the ability to absorb visible light well above 500 nm. This material has a great potential for splitting water under visible light irradiation. The availability of (Ga{sub 1-x}Zn{sub x})(N{sub 1-x}O{sub x}) solid solutions with a high Zn content opens the door to fully explore the application of these materials in photocatalysis.

  12. Keynes, R.J. and Stern, C.D. (1988) The development of neural segmentation in vertebrate embryos. In: The making of the nervous system. (J. Parnavelas, C.D. Stern and R.V. Stirling,

    E-Print Network [OSTI]

    Stern, Claudio

    1988-01-01T23:59:59.000Z

    . In: The making of the nervous system. (J. Parnavelas, C.D. Stern and R.V. Stirling, eds.). Oxford in vertebrate embryos. In: The making of the nervous system. (J. Parnavelas, C.D. Stern and R.V. Stirling, eds.V. Stirling, eds.). Oxford University Press pp. 84-100. #12;Keynes, R.J. and Stern, C.D. (1988

  13. A novel CD93 polymorphism in non-obese diabetic (NOD) and NZB/W F1 mice is linked to a CD4+ iNKT cell deficient state

    E-Print Network [OSTI]

    2010-01-01T23:59:59.000Z

    PE conjugated CD1d tetramer loaded with PBS-57 (Alpha-was prepared by the NIH Tetramer Facility. A total of 1–2 ×CD3 lo , PBS57-loaded CD1d Tetramer+) in the liver of B6 (n=

  14. Beta-delayed Neutron Spectroscopy of $^{130-132}$Cd Isotopes with the ISOLDE Decay Station and the VANDLE array

    E-Print Network [OSTI]

    Madurga Flores, Miguel; Kolos, K; Bardayan, D; Borge, M J G; Brewer, N T; Cocolios, T E; Cizewski, J A; Dillman, I; Fijalkowska, A; Fraile, L M; Gross, C J; Goetz, K C; Ilyushkin, S V; Mazzocchi, C; Manning, B; Miernik, K; Miller, D; Paulauskas, S V; Peters, W A; Ratkiewicz, A; Rykaczewski, K P; Taylor, S; Tengblad, O; Sotty, C; De Witte, H; Xiao, Y; CERN. Geneva. ISOLDE and neutron Time-of-Flight Experiments Committee; INTC

    2014-01-01T23:59:59.000Z

    Beta-delayed Neutron Spectroscopy of $^{130-132}$Cd Isotopes with the ISOLDE Decay Station and the VANDLE array

  15. CdTe Feedstock Development and Validation: Cooperative Research and Development Final Report, CRADA Number CRD-08-00280

    SciTech Connect (OSTI)

    Albin, D.

    2011-05-01T23:59:59.000Z

    The goal of this work was to evaluate different CdTe feedstock formulations (feedstock provided by Redlen) to determine if they would significantly improve CdTe performance with ancillary benefits associated with whether changes in feedstock would affect CdTe cell processing and possibly reliability of cells. Feedstock also included attempts to intentionally dope the CdTe with pre-selected elements.

  16. Interdiffusion and impurity diffusion in polycrystalline Mg solid solution with Al or Zn

    SciTech Connect (OSTI)

    Kammerer, Catherine [University of Central Florida, Orlando; Kulkarni, Nagraj S [ORNL; Warmack, Robert J Bruce [ORNL; Sohn, Yong Ho [University of Central Florida

    2014-01-01T23:59:59.000Z

    Interdiffusion and impurity diffusion in Mg binary solid solutions, Mg(Al) and Mg(Zn) were investigated at temperatures ranging from 623 to 723 K. Interdiffusion coef cients were determined via the Boltzmann Matano Method using solid-to-solid diffusion couples assembled with polycrystalline Mg and Mg(Al) or Mg(Zn) solid solutions. In addition, the Hall method was employed to extrapolate the impurity diffusion coef cients of Al and Zn in pure polycrystalline Mg. For all diffusion couples, electron micro-probe analysis was utilized for the measurement of concentration pro les. The interdiffusion coef cient in Mg(Zn) was higher than that of Mg(Al) by an order of magnitude. Additionally, the interdiffusion coef cient increased signi cantly as a function of Al content in Mg(Al) solid solution, but very little with Zn content in Mg(Zn) solid solution. The activation energy and pre-exponential factor for the average effective interdiffusion coef cient in Mg(Al) solid solution were determined to be 186.8 ( 0.9) kJ/mol and 7.69 x 10-1 ( 1.80 x 10-1) m2/s, respectively, while those determined for Mg(Zn) solid solution were 139.5 ( 4.0) kJ/mol and 1.48 x 10-3 ( 1.13 x 10-3) m2/s. In Mg, the Zn impurity diffusion coef cient was an order of magnitude higher than the Al impurity diffusion coef cient. The activation energy and pre-exponential factor for diffusion of Al impurity in Mg were determined to be 139.3 ( 14.8) kJ/mol and 6.25 x 10-5 ( 5.37 x 10-4) m2/s, respectively, while those for diffusion of Zn impurity in Mg were determined to be 118.6 ( 6.3) kJ/mol and 2.90 x 10-5 ( 4.41 x 10-5) m2/s.

  17. Electroluminescence from ZnO/Si heterojunctions fabricated by PLD with bias voltage application

    SciTech Connect (OSTI)

    Seno, Yuuki; Konno, Daisuke; Komiyama, Takao; Chonan, Yasunori; Yamaguchi, Hiroyuki; Aoyama, Takashi [Electronics and Information Systems, Akita Prefectural Univ. Yuri-honjo, Akita 015-0055 (Japan)

    2014-02-21T23:59:59.000Z

    Electroluminescence (EL) for ZnO films has been investigated by fabricating n-ZnO/p-Si heterojunctions and changing the VI/II (O/Zn) ratio of the films. In the photoluminescence (PL) spectra, both the near band edge (NBE) emission and the defect-related emission were observed, while in the EL spectra only defect-related emission was observed. The EL spectra were divided into three components: green (550 nm), yellow (618 nm) and red (700 nm) bands; and their intensities were compared. As the VI/II (O/Zn) ratio was increased, the red band emission intensity decreased and the green band emission intensity increased. This implies that the oxygen and the zinc vacancies are related to the red and the green band emissions, respectively. Electron transitions from the conduction band minimum (Ec) to the deep energy levels of these vacancies are suggested to cause the red and the green luminescences while the energy levels of the Zn interstitials are close to the Ec in the band gap and no NBE emission is observed.

  18. Emission dynamics of an expanding ultrafast-laser produced Zn plasma under different ambient pressures

    SciTech Connect (OSTI)

    Smijesh, N.; Philip, Reji [Raman Research Institute, C.V. Raman Avenue, Sadashivanagar, Bangalore 560080 (India)] [Raman Research Institute, C.V. Raman Avenue, Sadashivanagar, Bangalore 560080 (India)

    2013-09-07T23:59:59.000Z

    We report time and space resolved spectral measurements of neutral Zn emission from an ultrafast laser produced plasma, generated by the irradiation of a Zn target with laser pulses of 100 femtoseconds duration, carried out in a broad ambient pressure range of 0.05 to 100 Torr. The measurement is done for three different axial positions in the expanding plume. The spectra are rich in neutral Zn (Zn I) emissions at 334.5 nm, 468 nm, 472 nm, 481 nm, and 636 nm, respectively, depicting the characteristic triplet structure of Zn. Fast as well as slow peaks are observed in the time of flight data of 481 nm emission, which arise from recombination and atomic contributions, respectively, occurring at different time scales. Average speeds of the fast atomic species do not change appreciably with ambient pressure. The plasma parameters (electron temperature and number density) are evaluated from the measured optical emission spectra. The rates of ionization and recombination can be enhanced by a double-pulse excitation configuration in which optical energy is coupled to the ultrafast plasma through a delayed laser pulse.

  19. Dynamic recrystallization and texture evolution of Mg–Y–Zn alloy during hot extrusion process

    SciTech Connect (OSTI)

    Tong, L.B. [State Key Laboratory of Rare Earth Resources Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Li, X. [Institut für Metallkunde und Metallphysik, RWTH-Aachen University, D-52056 Aachen (Germany); Guangzhou Research Institute of Non-ferrous Metals, Guangzhou 510651 (China); Zhang, D.P.; Cheng, L.R.; Meng, J. [State Key Laboratory of Rare Earth Resources Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Zhang, H.J., E-mail: hongjie@ciac.ac.cn [State Key Laboratory of Rare Earth Resources Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China)

    2014-06-01T23:59:59.000Z

    The microstructure and texture evolution of Mg{sub 98.5}Y{sub 1}Zn{sub 0.5} and Mg{sub 92.5}Y{sub 5}Zn{sub 2.5} (atomic percent) alloys during hot extrusion were systematically investigated. The coarse LPSO phases with higher volume fraction (? 57%) suppressed the twinning generation in the initial stage of extrusion, and accelerated the dynamic recrystallization through the particle deformation zones. Therefore, the volume fraction of DRXed grains in as-extruded Mg{sub 92.5}Y{sub 5}Zn{sub 2.5} alloy was much higher than that of Mg{sub 98.5}Y{sub 1}Zn{sub 0.5} alloy. The intensive recrystallization process resulted in the conventional basal texture weakening, although the texture evolution was mainly dominated by flow behavior. The dynamic recrystallization behavior in Mg{sub 92.5}Y{sub 5}Zn{sub 2.5} alloy restricted the formation of deformation texture, and thus the more random texture was observed during the whole extrusion process. - Highlights: • The densely coarse LPSO phases suppressed the twinning deformation. • Coarse LPSO phases induced the particle stimulated nucleation effect. • Dynamic recrystallization resulted in the basal texture weakening effect.

  20. Cell-intrinsic Transforming Growth Factor-[beta] signaling mediates virus-specific CD8? T cell deletion and lymphocytic choriomeningitis virus persistence in vivo

    E-Print Network [OSTI]

    Tinoco, Roberto

    2010-01-01T23:59:59.000Z

    Persistent numbers of tetramer+ CD8(+) T cells, but loss ofepitopes were monitored by tetramer staining throughout theof peripheral blood tetramer-positive CD8 + T cells were

  1. Higgs Boson in RG running Inflationary Cosmology

    E-Print Network [OSTI]

    Yi-Fu Cai; Damien A. Easson

    2013-01-07T23:59:59.000Z

    An intriguing hypothesis is that gravity may be non-perturbatively renormalizable via the notion of asymptotic safety. We show that the Higgs sector of the SM minimally coupled to asymptotically safe gravity can generate the observed near scale-invariant spectrum of the Cosmic Microwave Background through the curvaton mechanism. The resulting primordial power spectrum places an upper bound on the Higgs mass, which for finely tuned values of the curvaton parameters, is compatible with the recently released Large Hadron Collider data.

  2. Biography Jörg Mönig

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041clothAdvanced Materials Advanced Materials Find Find More LikeAndreas Hampel Dr.

  3. J rg Calefice | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnual SiteofEvaluatingGroup | OpenHunanInformation sourceInvensysIsland GasItron Inc Jump to:JJ

  4. Characterization of CdS thin films grown by chemical bath deposition using four different cadmium sources

    E-Print Network [OSTI]

    Chow, Lee

    efficiency thin film solar cells based on CdTe and Cu(In,Ga)Se2 (CIGS) [3,4]. It has also been used in other used in solar cell applications [6,7]. Deposition of CdS using CBD is based on the slow release of Cd2

  5. Cu2ZnSnS x O4 x and Cu2ZnSnS x Se4 x : First principles simulations of optimal alloy configurations and their energies

    E-Print Network [OSTI]

    Holzwarth, Natalie

    .1063/1.4819206 The role of secondary phase precipitation on grain boundary electrical activity in Cu2ZnSnS4 (CZTS in thin film solar cells, multicomponent copper chalcogenide based com- pounds, namely, Cu2ZnSnS4(CZTS sulphide CZTS device has reported an efficiency of 8.4%,5 whereas the best pure selenide CZTSe device has

  6. Broad spectral response photodetector based on individual tin-doped CdS nanowire

    SciTech Connect (OSTI)

    Zhou, Weichang, E-mail: wchangzhou@gmail.com, E-mail: dstang@hunnu.edu.cn; Peng, Yuehua; Yin, Yanling; Zhou, Yong; Zhang, Yong; Tang, Dongsheng, E-mail: wchangzhou@gmail.com, E-mail: dstang@hunnu.edu.cn [Key Laboratory of Low-dimensional Quantum Structures and Quantum Control of Ministry of Education, College of Physics and Information Science, Hunan Normal University, Changsha 410081 (China)

    2014-12-15T23:59:59.000Z

    High purity and tin-doped 1D CdS micro/nano-structures were synthesized by a convenient thermal evaporation method. SEM, EDS, XRD and TEM were used to examine the morphology, composition, phase structure and crystallinity of as-prepared samples. Raman spectrum was used to confirm tin doped into CdS effectively. The effect of impurity on the photoresponse properties of photodetectors made from these as-prepared pure and tin-doped CdS micro/nano-structures under excitation of light with different wavelength was investigated. Various photoconductive parameters such as responsivity, external quantum efficiency, response time and stability were analyzed to evaluate the advantage of doped nanowires and the feasibility for photodetector application. Comparison with pure CdS nanobelt, the tin-doped CdS nanowires response to broader spectral range while keep the excellect photoconductive parameters. Both trapped state induced by tin impurity and optical whispering gallery mode microcavity effect in the doped CdS nanowires contribute to the broader spectral response. The micro-photoluminescence was used to confirm the whispering gallery mode effect and deep trapped state in the doped CdS nanowires.

  7. Studies on optoelectronic properties of DC reactive magnetron sputtered CdTe thin films

    SciTech Connect (OSTI)

    Kumar, B. Rajesh, E-mail: rajphyind@gmail.com [Department of Physics, Sri Venkateswara University, Tirupati - 517 502, A.P, India and Department of Physics, Sri Krishnadevaraya University, Anantapur - 515 003, A.P (India); Hymavathi, B.; Rao, T. Subba [Department of Physics, Sri Krishnadevaraya University, Anantapur - 515 003, A.P (India)

    2014-01-28T23:59:59.000Z

    Cadmium telluride continues to be a leading candidate for the development of cost effective photovoltaics for terrestrial applications. In the present work two individual metallic targets of Cd and Te were used for the deposition of CdTe thin films on mica substrates from room temperature to 300 °C by DC reactive magnetron sputtering method. XRD patterns of CdTe thin films deposited on mica substrates exhibit peaks at 2? = 27.7°, 46.1° and 54.6°, which corresponds to reflection on (1 1 1), (2 2 0) and (3 1 1) planes of CdTe cubic structure. The intensities of XRD patterns increases with the increase of substrate temperature upto 150 °C and then it decreases at higher substrate temperatures. The conductivity of CdTe thin films measured from four probe method increases with the increase of substrate temperature. The activation energies (?E) are found to be decrease with the increase of substrate temperature. The optical transmittance spectra of CdTe thin films deposited on mica have a clear interference pattern in the longer wavelength region. The films have good transparency (T > 85 %) exhibiting interference pattern in the spectral region between 1200 – 2500 nm. The optical band gap of CdTe thin films are found to be in the range of 1.48 – 1.57. The refractive index, n decreases with the increase of wavelength, ?. The value of n and k increases with the increase of substrate temperature.

  8. A Novel and Functional Single Layer Sheet of ZnSe

    SciTech Connect (OSTI)

    Zhou, Jia [ORNL; Sumpter, Bobby G [ORNL; Kent, Paul R [ORNL; Huang, Jingsong [ORNL

    2015-01-01T23:59:59.000Z

    In this Communication, we report a novel singlelayer sheet of ZnSe, with a three-atomic thickness, which demonstrates a strong quantum confinement effect by exhibiting a large blue shift of 2.0 eV in its absorption edge relative to the zinc blende (ZB) bulk phase. Theoretical optical absorbance shows that the largest absorption of this ultrathin single-layer sheet of ZnSe occurs at a wavelength similar to its four-atom-thick doublelayer counterpart but with higher photoabsorption efficiency, suggesting a superior behavior on incident photon-to-current conversion efficiency for solar water splitting, among other potential applications. The results presented herein for ZnSe may be generalized to other group II-VI analogues.

  9. Homojunction p-n photodiodes based on As-doped single ZnO nanowire

    SciTech Connect (OSTI)

    Cho, H. D.; Zakirov, A. S.; Yuldashev, Sh. U.; Kang, T. W. [Quantum-Functional Semiconductor Research Center, Dongguk Univ.-Seoul, Seoul 100-715 (Korea, Republic of); Ahn, C. W. [Nano-materials Lab. National Nanofab Center at KAIST, 335 Gwahangno, Daejeon 305-806 (Korea, Republic of); Yeo, Y. K. [Department of Engineering Physics, Air Force Institute of Technology,Wright-Patterson AFB, OH 45433 (United States)

    2013-12-04T23:59:59.000Z

    Photovoltaic device was successfully grown solely based on the single ZnO p-n homojunction nanowire. The ZnO nanowire p-n diode consists of an as-grown n-type segment and an in-situ arsenic doped p-type segment. This p-n homojunction acts as a good photovoltaic cell, producing a photocurrent almost 45 times larger than the dark current under reverse-biased condition. Our results demonstrate that present ZnO p-n homojunction nanowire can be used as a self-powered ultraviolet photodetector as well as a photovoltaic cell, which can also be used as an ultralow electrical power source for nano-scale electronic, optoelectronic, and medical devices.

  10. Reliable self-powered highly spectrum-selective ZnO ultraviolet photodetectors

    SciTech Connect (OSTI)

    Shen, H. [State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033 (China) [State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Shan, C. X., E-mail: shancx@ciomp.ac.cn, E-mail: binghuili@163.com; Li, B. H., E-mail: shancx@ciomp.ac.cn, E-mail: binghuili@163.com; Shen, D. Z. [State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033 (China)] [State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033 (China); Xuan, B. [Key Laboratory of Optical System Advanced Manufacturing Technology, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033 (China)] [Key Laboratory of Optical System Advanced Manufacturing Technology, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033 (China)

    2013-12-02T23:59:59.000Z

    Ultraviolet photodetectors (PDs) have been fabricated from p-ZnO:(Li,N)/n-ZnO structures in this Letter. The PDs can operate without any external power supply and show response only to a very narrow spectrum range. The self-power character of the devices is due to the built-in electric field in the p-n junctions that can separate the photogenerated electrons and holes while the high spectrum-selectivity has been attributed to the filter effect of the neutral region in the ZnO:(Li,N) layer. The performance of the self-powered highly spectrum-selective PDs degrades little after five months, indicating their good reliability.

  11. Far-infrared optical and dielectric response of ZnS measured by terahertz time-domain spectroscopy

    E-Print Network [OSTI]

    Far-infrared optical and dielectric response of ZnS measured by terahertz time-domain spectroscopy material in the infrared and far-infrared region.1 It plays a vital role in being used as infrared windows the frequency-dependent optical properties and complex di- electric response of ZnS over a broad far-infrared

  12. Effect of Pre-Aging on the Microstructure and Strength of Supersaturated AlZnMg Alloys Processed by ECAP

    E-Print Network [OSTI]

    Gubicza, Jenõ

    Effect of Pre-Aging on the Microstructure and Strength of Supersaturated AlZnMg Alloys Processed-059 Kraków, Poland 3 Departments of Aerospace & Mechanical Engineering and Materials Science, University langdon@usc.edu Keywords: Supersaturated AlZnMg alloys, natural aging, Guinier-Prestion zones, Equal

  13. Optical spectra of ZnO in the far ultraviolet: First-principles calculations and ellipsometric measurements

    E-Print Network [OSTI]

    Nabben, Reinhard

    February 2010; published 19 March 2010 We present ellipsometry data of the dielectric function of wurtzite anisotropy above 10 eV, a feature for which ZnO deviates from the other II-VI wurtzite compounds on the optical response of bulk wurtzite wz ZnO, reporting ellipsometric measurements in the far UV. Ellipsometry

  14. Controlled synthesis and manipulation of ZnO nanorings and nanobows William L. Hughes and Zhong L. Wanga

    E-Print Network [OSTI]

    Wang, Zhong L.

    Controlled synthesis and manipulation of ZnO nanorings and nanobows William L. Hughes and Zhong L An experimental procedure is presented for the controlled synthesis and manipulation of ZnO nanorings and nanobows at high purity and large yield. Atomic force microscopy manipulation of the nanostructures demonstrates

  15. Temperature dependence of magnetic behaviour in very fine grained, spark plasma sintered NiCuZn Ferrites

    E-Print Network [OSTI]

    Boyer, Edmond

    CuZn Ferrites Behzad Ahmadi,1, a) Karim Zehani,1 Martino LoBue,1 Vincent Loyau,1 and Frederic Mazaleyrat1 SATIE spark plasma sintering technique, a family of very fine grained, fully dense NiCuZn ferrites have been produced which show constant permeability up to several 10 MHz. These Ferrites can be used for filtering

  16. Growth of Single-and Bilayer ZnO on Au(111) and Interaction with Xingyi Deng,*,,,

    E-Print Network [OSTI]

    Li, Weixue

    Growth of Single- and Bilayer ZnO on Au(111) and Interaction with Copper Xingyi Deng,*,,§, Kun Yao of Sciences, Dalian 116023, China § URS, P.O. Box 618, South Park, Pennsylvania 15129, United States *S for the structure of the grown ultrathin ZnO, in particular how important the interaction between the substrate

  17. Effet de l'apport de phosphore, de carbonate de calcium et d'oligo-lments (Cu, Mn, Zn, B)

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Agronomie Effet de l'apport de phosphore, de carbonate de calcium et d'oligo-éléments (Cu, Mn, Zn apports de phosphore, de carbonate de calcium et d'oligo-éléments (Mn, Cu, Zn, B), en vue de mieux celles de B lorsqu'on élève le pH par apport de carbonate de calcium; - l'accumulation préférentielle de

  18. Substrate Atomic-Termination-Induced Anisotropic Growth of ZnO Nanowires/Nanorods by the VLS Process

    E-Print Network [OSTI]

    Wang, Zhong L.

    Substrate Atomic-Termination-Induced Anisotropic Growth of ZnO Nanowires/Nanorods by the VLSO substrate, we demonstrate the effect of substrate surface termination on nanowire growth. Symmetric) substrates have asymmetrically grown nanostructures. For the Zn-terminated (0001) substrate surface, uniform

  19. DOI: 10.1002/adma.200602927 Hierarchically Structured ZnO Film for Dye-Sensitized Solar Cells

    E-Print Network [OSTI]

    Cao, Guozhong

    DOI: 10.1002/adma.200602927 Hierarchically Structured ZnO Film for Dye-Sensitized Solar Cells* The interest in dye-sensitized solar cells has increased due to reduced energy sources and higher energy, zinc oxide (ZnO) has recently been explored as an alternative material in dye-sensitized solar cells

  20. Flexible dye-sensitized solar cells with ZnO nanoparticles grown by Sonochemistry over Graphene/PET substrates.

    E-Print Network [OSTI]

    Pala, Nezih

    Flexible dye-sensitized solar cells with ZnO nanoparticles grown by Sonochemistry over Graphene and Engineering University of North Texas, Denton, Texas Flexible Dye sensitized solar cells (FDSSCs) are light characteristics of ZnO nanostructures over Graphene/PET as photoanode for flexible dye sensitized solar cells. #12;

  1. Simplifying strong electronic correlations in uranium: Localized uranium heavy-fermion UM2Zn20 (M=Co,Rh) compounds

    E-Print Network [OSTI]

    Lawrence, Jon

    Simplifying strong electronic correlations in uranium: Localized uranium heavy-fermion UM2Zn20 (M Atómica, 8400 Bariloche, Argentina 6 Department of Chemistry and Biochemistry, University of Delaware-field effects corroborate an ionic-like uranium electronic configura- tion in UM2Zn20. DOI: 10.1103/PhysRevB.78

  2. Catalysis Letters Vol. 77, No. 4, 2001 197 Effects of Zn, Cu, and K promoters on the structure

    E-Print Network [OSTI]

    Iglesia, Enrique

    and on the reduction, carburization, and catalytic behavior of iron-based Fischer­Tropsch synthesis catalysts Senzi Li, and catalytic behavior of Fe­Zn and Fe oxides used as precursors to Fischer­Tropsch synthesis (FTS) catalysts­Zn oxide precursors. KEY WORDS: Fischer­Tropsch synthesis; promoters; iron; carbide; copper; potassium

  3. Growth Mechanism and Electronic Structure of Zn3P2 on the Ga-Rich GaAs(001) Surface

    E-Print Network [OSTI]

    Atwater, Harry

    as well as the potential for low-cost, thin-film fabrication make Zn3P2 a promising active material Zn3P2 films on III-V substrates unlocks a promising pathway toward high-efficiency, earth-abundant photovoltaic devices fabricated on reusable, single-crystal templates. The detailed chemical, structural

  4. Study of Even-Even/Odd-Even/Odd-Odd Nuclei in Zn-Ga-Ge Region in the Proton-Neutron IBM/IBFM/IBFFM

    SciTech Connect (OSTI)

    Yoshida, N. [Faculty of Informatics, Kansai University, Takatsuki 569-1095 (Japan); Brant, S. [Department of Physics, Faculty of Science, University of Zagreb, 10000 Zagreb (Croatia); Zuffi, L. [Dipartimento di Fisica dell'Universita di Milano and Istituto Nazionale di Fisica Nucleare, Sezione di Milano, Via Celoria 16, Milano 20133 (Italy)

    2009-08-26T23:59:59.000Z

    We study the even-even, odd-even and odd-odd nuclei in the region including Zn-Ga-Ge in the proton-neutron IBM and the models derived from it: IBM2, IBFM2, IBFFM2. We describe {sup 67}Ga, {sup 65}Zn, and {sup 68}Ga by coupling odd particles to a boson core {sup 66}Zn. We also calculate the beta{sup +}-decay rates among {sup 68}Ge, {sup 68}Ga and {sup 68}Zn.

  5. Low background detector with enriched 116CdWO4 crystal scintillators to search for double beta decay of 116Cd

    E-Print Network [OSTI]

    A. S. Barabash; P. Belli; R. Bernabei; R. S. Boiko; F. Cappella; V. Caracciolo; D. M. Chernyak; R. Cerulli; F. A. Danevich; M. L. Di Vacri; A. E. Dossovitskiy; E. N. Galashov; A. Incicchitti; V. V. Kobychev; S. I. Konovalov; G. P. Kovtun; V. M. Kudovbenko; M. Laubenstein; A. L. Mikhlin; S. Nisi; D. V. Poda; R. B. Podviyanuk; O. G. Polischuk; A. P. Shcherban; V. N. Shlegel; D. A. Solopikhin; Yu. G. Stenin; V. I. Tretyak; V. I. Umatov; Ya. V. Vasiliev; V. D. Virich

    2011-08-13T23:59:59.000Z

    A cadmium tungstate crystal boule enriched in $^{116}$Cd to 82% with mass of 1868 g was grown by the low-thermal-gradient Czochralski technique. The isotopic composition of cadmium and the trace contamination of the crystal were estimated by High Resolution Inductively Coupled Plasma Mass-Spectrometry. The crystal scintillators produced from the boule were subjected to characterization that included measurements of transmittance and energy resolution. A low background scintillation detector with two $^{116}$CdWO$_4$ crystal scintillators (586 g and 589 g) was developed. The detector was running over 1727 h deep underground at the Gran Sasso National Laboratories of the INFN (Italy), which allowed to estimate the radioactive contamination of the enriched crystal scintillators. The radiopurity of a third $^{116}$CdWO$_4$ sample (326 g) was tested with the help of ultra-low background high purity germanium $\\gamma$ detector. Monte Carlo simulations of double $\\beta$ processes in $^{116}$Cd were used to estimate the sensitivity of an experiment to search for double $\\beta$ decay of $^{116}$Cd.

  6. ZnO Nanorod Thermoplastic Polyurethane Nanocomposites: Morphology and Shape Memory Performance

    SciTech Connect (OSTI)

    Koerner, H.; Kelley, J; George, J; Drummy, L; Mirau, P; Bell, N; Hsu, J; Vaia, R

    2009-01-01T23:59:59.000Z

    The impact of dispersed alkylthiol-modified ZnO nanorods, as a function of rod aspect ratio and concentration, on the shape memory character of a thermoplastic polyurethane with low hard-segment density (LHS-TPU) is examined relative to the enhanced performance occurring for carbon nanofiber (CNF) dispersion. Solution blending resulted in uniform dispersion within the LHS-TPU of the ZnO nanorods at low volume (weight) fractions (<2.9% v/v (17.75% w/w)). Tensile modulus enhancements were modest though, comparable to values observed for spherical nanofillers. Shape memory characteristics, which in this LHS-TPU result when strain-induced crystallites retard the entropic recovery of the deformed chains, were unchanged for these low volume fraction ZnO nanocomposites. Higher ZnO loadings (12% v/v (50% w/w)) exhibited clustering of ZnO nanorods into a mesh-like structure. Here, tensile modulus and shape recovery characteristics were improved, although not as great as seen for comparable CNF addition. Wide angle X-ray diffraction and NMR revealed that the addition of ZnO nanorods did not impact the inherent strain induced crystallization of the LHS-TPU, which is in contrast to the impact of CNFs and emphasizes the impact of interactions at the polymer-nanoparticle interface. Overall, these findings reinforce the hypothesis that the shape memory properties of polymer nanocomposites are governed by the extent to which nanoparticle addition, via nanoparticle aspect ratio, hierarchical morphology, and interfacial interactions, impacts the molecular mechanism responsible for trapping elastic strain.

  7. Synthesis of CdS nanoparticles for photocatalytic application of methyleneblue degradation

    SciTech Connect (OSTI)

    Muthuraj, V., E-mail: muthuraj75@gmail.com [Research Department of Chemistry, VHNSN College, Virudhunagar-626001 (India); Umadevi, M. [Department of Chemistry, Nehru Memorial College, Puthanampatti, Trichy-621007, Tamilnadu (India); Sankarasubramanian, K.; Kajamuhideen, M. S. [School of Physics, Madurai Kamaraj University, Madurai-625 021, Tamilnadu (India)

    2014-04-24T23:59:59.000Z

    CdS nanoparticles were prepared by the reaction of cadmium acetate with thiourea in the presence and absence of methylene blue dye (MB). The nanoparticles were characterized by, XRD, FT-IR, UV-Vis. XRD study shows the presence of hexagonal phase for the nanoparticles whereas in case of the bulk samples only the hexagonal phase is observed. Fourier transform infrared spectroscopy (FT-IR) showed a strong interaction of methyl groups with CdS nanoparticles. The degradation of methylene blue was analysed using UV-Vis absorbance spectrum. Thus the results authenticate that methylene blue dye influences the structural and optical properties of the CdS nanoparticles.

  8. Thin-film CdTe and CuInSe{sub 2} photovoltaic technologies

    SciTech Connect (OSTI)

    Ullal, H.S.; Zweibel, K.; von Roedern, B.G.

    1993-08-01T23:59:59.000Z

    Total-area conversion efficiency of 15%--15.8% have been achieved for thin-film CdTe and CIS solar cells. Modules with power output of 5--53 W have been demonstrated by several groups world-wide. Critical processes and reaction pathways for achieving excellent PV devices have been eluciated. Research, development and technical issues have been identified, which could result in potential improvements in device and module performance. A 1-kW thin-film CdTe array has been installed and is being tested. Multimegawatt thin-film CdTe manufacturing plants are expected to be completed in 1-2 years.

  9. Chapter 1.19: Cadmium Telluride Photovoltaic Thin Film: CdTe

    SciTech Connect (OSTI)

    Gessert, T. A.

    2012-01-01T23:59:59.000Z

    The chapter reviews the history, development, and present processes used to fabricate thin-film, CdTe-based photovoltaic (PV) devices. It is intended for readers who are generally familiar with the operation and material aspects of PV devices but desire a deeper understanding of the process sequences used in CdTe PV technology. The discussion identifies why certain processes may have commercial production advantages and how the various process steps can interact with each other to affect device performance and reliability. The chapter concludes with a discussion of considerations of large-area CdTe PV deployment including issues related to material availability and energy-payback time.

  10. XPS and AES Studies of Cu/CdTe(111)-B

    SciTech Connect (OSTI)

    Teeter, G.; Gessert, T. A.; Asher, S. E.

    2005-01-01T23:59:59.000Z

    Copper is frequently used as a p-type dopant to improve the performance of back contacts in CdTe thin-film solar cells. In this study, surface-analysis techniques are used to probe fundamental interactions between Cu and the CdTe(111)-B surface. The results presented here were facilitated by the newly constructed surface-analysis cluster tool in the Measurements and Characterization Division at NREL; they reveal a host of fundamental phenomena that occur in the Cu/CdTe system.

  11. Double beta decay of ^{64,70}Zn and ^{180,186}W isotopes

    E-Print Network [OSTI]

    D. V. Poda

    2011-12-05T23:59:59.000Z

    The results of the experimental investigations of double beta processes in Zinc and Tungsten isotopes with the help of middle volume (117 g, 168 g and 699 g) low-background ZnWO_4 crystal scintillators are presented. The experiment was carried out in the low-background "DAMA/R&D" set-up at the Gran Sasso National Laboratories of the INFN (Italy) at a depth of \\approx3600 m w.e. The total measurement time exceeds ten thousand hours. New improved half-life limits on double electron capture and electron capture with positron emission in ^{64}Zn have been set: T^{2\

  12. ZnTe:O phosphor development for x-ray imaging applications

    SciTech Connect (OSTI)

    Kang, Z.T.; Summers, C.J.; Menkara, H.; Wagner, B.K.; Durst, R.; Diawara, Y.; Mednikova, G.; Thorson, T. [Phosphor Technology Center of Excellence, School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245 (United States); Georgia Tech Research Institute, Georgia Institute of Technology, Atlanta, Georgia 30332-0826 (United States); Bruker AXS 5465 East Cheryl Parkway, Madison Wisconson 53711 (United States)

    2006-03-13T23:59:59.000Z

    An efficient ZnTe:O x-ray powder phosphor was prepared by a dry synthesis process using gaseous doping and etching medias. The x-ray luminescent properties were evaluated and compared to standard commercial phosphors exhibited an x-ray luminescent efficiency equivalent to 76% of Gd{sub 2}O{sub 2}S:Tb and an equal resolution of 2.5 lines/mm. In addition, the fast decay time, low afterglow, and superior spectral match to conventional charge-coupled devices-indicate that ZnTe:O is a very promising phosphor candidate for x-ray imaging applications.

  13. Preparation and characterization of nanodiamond cores coated with a thin Ni-Zn-P alloy film

    SciTech Connect (OSTI)

    Wang Rui; Ye Weichun; Ma Chuanli [College of Chemistry and Chemical Engineering, Lanzhou University, 730000 Lanzhou (China); Wang Chunming [College of Chemistry and Chemical Engineering, Lanzhou University, 730000 Lanzhou (China)], E-mail: wangcm@lzu.edu.cn

    2008-02-15T23:59:59.000Z

    Nanodiamond cores coated with a thin Ni-Zn-P alloy film were prepared by an electroless deposition method under the conditions of tin chloride sensitization and palladium chloride activation. The prepared materials were analyzed by Fourier transform infrared (FTIR) spectrometry and X-ray diffraction (XRD). The nanostructure of the materials was then characterized by transmission electron microscopy (TEM). The alloy film composition was characterized by Energy Dispersive X-ray (EDX) analysis. The results indicated the approximate composition 49.84%Ni-37.29%Zn-12.88%P was obtained.

  14. Laser Treatment of Ag@ZnO Nanorods as Long Life Span SERS Surfaces

    E-Print Network [OSTI]

    Macias-Montero, Manuel; J. Peláez, Ramón; Rico, Victor J.; Saghi, Zineb; Midgley, Paul; Afonso, Carmen N.; González-Elipe, Agustín R.; Borras, Ana

    2015-01-09T23:59:59.000Z

    on semiconductor nanorods or nanowires of Si, Ge or ZnO, have led to significant enhancements in Raman scattering. 18,19 These evidences have prompted the study of composites or heterostructures formed by semiconductors and noble metals to promote higher SERS... of Surface-Enhanced Raman Scattering in ZnO Nanocrystals. J. Raman Spectrosc., 2009, 40, 1072-1077. 18 Li, X. H.; Chen, G. Y.; Yang, L. B.; Jin Z.; Liu, J. H. Multifunctional Au-Coated TiO2 Nanotube Arrays as Recyclable SERS Substrates for Multifold...

  15. Laser Treatment of Ag@ZnO Nanorods as Long-Life-Span SERS Surfaces

    E-Print Network [OSTI]

    Macias-Montero, Manuel; Peláez, Ramón J.; Rico, Victor J.; Saghi, Zineb; Midgley, Paul; Afonso, Carmen N.; González-Elipe, Agustín R.; Borras, Ana

    2015-01-09T23:59:59.000Z

    on semiconductor nanorods or nanowires of Si, Ge or ZnO, have led to significant enhancements in Raman scattering. 18,19 These evidences have prompted the study of composites or heterostructures formed by semiconductors and noble metals to promote higher SERS... of Surface-Enhanced Raman Scattering in ZnO Nanocrystals. J. Raman Spectrosc., 2009, 40, 1072-1077. 18 Li, X. H.; Chen, G. Y.; Yang, L. B.; Jin Z.; Liu, J. H. Multifunctional Au-Coated TiO2 Nanotube Arrays as Recyclable SERS Substrates for Multifold...

  16. Impurity Diffusion Coefficients of Al and Zn in Mg Determined from Solid-to-Solid Diffusion Couples

    SciTech Connect (OSTI)

    Kammerer, Catherine [University of Central Florida, Orlando; Kulkarni, Nagraj S [ORNL; Warmack, Robert J Bruce [ORNL; Perry, Kelly A [ORNL; Belova, Irina [University of Newcastle, NSW, Australia; Murch, Prof. Graeme [University of Newcastle, NSW, Australia; Sohn, Yong Ho [University of Central Florida

    2013-08-01T23:59:59.000Z

    Increasing use and development of lightweight Mgalloys have led to the desire for more fundamental research in and understanding of Mg-based systems. As property enhancing components, Al and Zn are two of the most important and common alloying elements for Mg-alloys. We have investigated the concentration dependent interdiffusion of Al and Zn in Mg using diffusion couples of pure polycrystalline Mg mated to Mg solid solutions containing either <9 at.% Al or <3 at.% Zn. Concentration profiles were determined by electron micro-probe microanalysis of the diffusion zone. The interdiffusion coefficients were determined by the classical Boltzmann-Matano method within the Mg solid solution. As the concentration of Al or Zn approaches the dilute ends, we employ an analytical approach based on the Hall method to estimate the impurity diffusion coefficients. Results of Al and Zn impurity diffusion in Mg are reported and compared to published impurity diffusion coefficients typically determined by thin film techniques.

  17. Engineering of optical polarization based on electronic band structures of A-plane ZnO layers under biaxial strains

    SciTech Connect (OSTI)

    Matsui, Hiroaki, E-mail: hiroaki@ee.t.u-tokyo.ac.jp; Tabata, Hitoshi [Department of Bioengineering, The University of Tokyo, 1-3-7 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Department of Electrical Engineering and Information Systems, The University of Tokyo, 1-3-7 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Hasuike, Noriyuki; Harima, Hiroshi [Department of Electronics and Information Science, Kyoto Institute of Technology, Sakyo-ku, Kyoto 606-8585 (Japan)

    2014-09-21T23:59:59.000Z

    In-plane anisotropic strains in A-plane layers on the electronic band structure of ZnO were investigated from the viewpoint of optical polarization anisotropy. Investigations utilizing k·p perturbation theory revealed that energy transitions and associated oscillation strengths were dependent on in-plane strains. The theoretical correlation between optical polarizations and in-plane strains was experimentally demonstrated using A-plane ZnO layers with different in-plane strains. Finally, optical polarization anisotropy and its implications for in-plane optical properties are discussed in relation to the energy shift between two orthogonal directions. Higher polarization rotations were obtained in an A-plane ZnO layer with in-plane biaxially compressive strains as compared to strain-free ZnO. This study provides detailed information concerning the role played by in-plane strains in optically polarized applications based on nonpolar ZnO in the ultra-violet region.

  18. Structure and stability of NH complexes in single-crystal ZnO S. J. Jokela and M. D. McCluskeya

    E-Print Network [OSTI]

    McCluskey, Matthew

    Received 20 March 2010; accepted 4 May 2010; published online 11 June 2010 Zinc oxide ZnO is semiconductor.1063/1.3443457 I. INTRODUCTION The renewed interest in zinc oxide ZnO has continued to grow over the last decade conductor.2 ZnO is already prevalent in industry, in devices such as solar cells3 and varistors.4 Research

  19. Role of copper in the regulation of CU, ZN-superoxide dismutase in human K562 erythroleukemia cells and human fibroblasts

    E-Print Network [OSTI]

    Yu, Dan

    1994-01-01T23:59:59.000Z

    Activation of the enzyme CU2Zn2-SUperoxide dismutase (CuZnSOD) by its copper cofactor was studied in K562 erythroleukemia cells and skin fibroblasts. K562 cells were incubated in medium supplemented with 0-50 IIM CUC12 or ZnCI2 for 24 h and extracts...

  20. Effects of Dye Loading Conditions on the Energy Conversion Efficiency of ZnO and TiO2 Dye-Sensitized Solar Cells

    E-Print Network [OSTI]

    Cao, Guozhong

    light conversion efficiency of zinc oxide (ZnO) film electrodes in dye-sensitized solar cellsO) has been explored as an alternative material in dye-sensitized solar cells. The use of Zn as an alternative material for improving the solar cell performance in dye-sensitized solar cells due to (1) Zn