National Library of Energy BETA

Sample records for tiny crystals glow

  1. Glow discharge detector

    DOE Patents [OSTI]

    Koo, Jackson C. (San Ramon, CA); Yu, Conrad M. (Antioch, CA)

    2002-01-01

    A highly sensitive electronic ion cell for the measurement of trace elements in He carrier gas which involves glow discharge. A constant wave (CW) glow discharge detector which is controlled through a biased resistor, can detect the change of electron density caused by impurities in the He carrier gas by many orders of magnitude larger than that caused by direct ionization or electron capture. The glow discharge detector utilizes a floating pseudo-electrode to form a probe in or near the plasma. By using this probe, the large variation of electron density due to trace amounts of impurities can be directly measured.

  2. From the tiny atom to

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

    From the tiny atom to the supernovae Atom-split it for nuclear energy Fermi-leader of the team that produced the first self-sustain- ing controlled nuclear chain reaction; contributed to ending WWII Calutron-invented by E. O. Lawrence; for maximum pro- ductivity, critical sensitive adjustments were provided by the 'Calutron Girls' Seaborg-Chairman of the Atomic Energy Commission 1961-1971; discovered many elements Buckyball-Buckminsterfullerene; 60 carbon atoms in the shape of a soccer ball;

  3. Stable glow discharge detector

    DOE Patents [OSTI]

    Koo, Jackson C.; Yu, Conrad M.

    2004-05-18

    A highly sensitive electronic ion cell for the measurement of trace elements in He carrier gas which involves glow discharge. A constant wave (CW) stable glow discharge detector which is controlled through a biased resistor, can detect the change of electron density caused by impurities in the He carrier gas by many orders of magnitude larger than that caused by direct ionization or electron capture. The stable glow discharge detector utilizes a floating pseudo-electrode to form a probe in or near the plasma and a solid rod electrode. By using this probe, the large variation of electron density due to trace amounts of impurities can be directly measured. The solid rod electrode provides greater stability and thus easier alignment.

  4. Measuring Tiny Waves with High Power Particle Beams | Princeton...

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

    Measuring Tiny Waves with High Power Particle Beams American Fusion News Category: U.S. Universities Link: Measuring Tiny Waves with High Power Particle Beams...

  5. Tiny Glass Bubbles With Big Potential

    Broader source: Energy.gov [DOE]

    If these glass microspheres' walls could talk…They would explain how their tiny pores allow the potential for handling, storing and transporting a variety of materials, including drugs that have...

  6. Powerful glow discharge excilamp

    DOE Patents [OSTI]

    Tarasenko, Victor F.; Panchenko, Aleksey N.; Skakun, Victor S.; Sosnin, Edward A.; Wang, Francis T.; Myers, Booth R.; Adamson, Martyn G.

    2002-01-01

    A powerful glow discharge lamp comprising two coaxial tubes, the outer tube being optically transparent, with a cathode and anode placed at opposite ends of the tubes, the space between the tubes being filled with working gas. The electrodes are made as cylindrical tumblers placed in line to one other in such a way that one end of the cathode is inserted into the inner tube, one end of the anode coaxially covers the end of the outer tube, the inner tube penetrating and extending through the anode. The increased electrodes' surface area increases glow discharge electron current and, correspondingly, average radiation power of discharge plasma. The inner tube contains at least one cooling liquid tube placed along the axis of the inner tube along the entire lamp length to provide cathode cooling. The anode has a circumferential heat extracting radiator which removes heat from the anode. The invention is related to lighting engineering and can be applied for realization of photostimulated processes under the action of powerful radiation in required spectral range.

  7. Nexus Energy Center Unveils Energy-Efficient Tiny Home | Department...

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

    Unveils Energy-Efficient Tiny Home Nexus Energy Center Unveils Energy-Efficient Tiny Home Photo of a man working on a house near a window. Better Buildings Residential Network ...

  8. Tiny magnets could work in sensors, information encoding

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

    Tiny magnets could work in sensors, information encoding Tiny magnets could work in sensors, information encoding Scientists have realized a nanoscale, artificial magnet by arranging an array of magnetic nano-islands along a geometry that is not found in natural magnets. November 1, 2015 Tiny magnets could work in sensors, information encoding Researchers have created a nanoscale, artificial magnet by arranging an array of magnetic nano-islands along a geometry that is not found in natural

  9. Constricted glow discharge plasma source

    DOE Patents [OSTI]

    Anders, Andre (Albany, CA); Anders, Simone (Albany, CA); Dickinson, Michael (San Leandro, CA); Rubin, Michael (Berkeley, CA); Newman, Nathan (Winnetka, IL)

    2000-01-01

    A constricted glow discharge chamber and method are disclosed. The polarity and geometry of the constricted glow discharge plasma source is set so that the contamination and energy of the ions discharged from the source are minimized. The several sources can be mounted in parallel and in series to provide a sustained ultra low source of ions in a plasma with contamination below practical detection limits. The source is suitable for applying films of nitrides such as gallium nitride and oxides such as tungsten oxide and for enriching other substances in material surfaces such as oxygen and water vapor, which are difficult process as plasma in any known devices and methods. The source can also be used to assist the deposition of films such as metal films by providing low-energy ions such as argon ions.

  10. Tiny Particles with Big Magnetic Power | Argonne National Laboratory

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

    Argonne scientists have developed a new material known as magnetic nanofibers to create more efficient magnets. PDF icon Nano Sheet_tiny particles

  11. Tamil Nadu Small and Tiny Industries Association TANSTIA | Open...

    Open Energy Info (EERE)

    Association TANSTIA Jump to: navigation, search Name: Tamil Nadu Small and Tiny Industries Association (TANSTIA) Place: India Sector: Services Product: Services & Support...

  12. Glow Plug Integrated Piezo-Ceramic Combustion Sensor for Diesel...

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

    Glow Plug Integrated Piezo-Ceramic Combustion Sensor for Diesel Engines Glow Plug Integrated Piezo-Ceramic Combustion Sensor for Diesel Engines 2005 Diesel Engine Emissions ...

  13. Atmospheric sampling glow discharge ionization source

    DOE Patents [OSTI]

    McLuckey, S.A.; Glish, G.L.

    1989-07-18

    An atmospheric sampling glow discharge ionization source that can be used in combination with an analytical instrument which operates at high vacuum, such as a mass spectrometer. The atmospheric sampling glow discharge ionization source comprises a chamber with at least one pair of electrodes disposed therein, an inlet for a gaseous sample to be analyzed and an outlet communicating with an analyzer which operates at subatmospheric pressure. The ionization chamber is maintained at a pressure below atmospheric pressure, and a voltage difference is applied across the electrodes to induce a glow discharge between the electrodes, so that molecules passing through the inlet are ionized by the glow discharge and directed into the analyzer. The ionization source accepts the sample under atmospheric pressure conditions and processes it directly into the high vacuum instrument, bridging the pressure gap and drawing off unwanted atmospheric gases. The invention also includes a method for analyzing a gaseous sample using the glow discharge ionization source described above. 3 figs.

  14. Atmospheric sampling glow discharge ionization source

    DOE Patents [OSTI]

    McLuckey, Scott A. (Oak Ridge, TN); Glish, Gary L. (Oak Ridge, TN)

    1989-01-01

    An atmospheric sampling glow discharge ionization source that can be used in combination with an analytical instrument which operates at high vacuum, such as a mass spectrometer. The atmospheric sampling glow discharge ionization source comprises a chamber with at least one pair of electrodes disposed therein, an inlet for a gaseous sample to be analyzed and an outlet communicating with an analyzer which operates at subatmospheric pressure. The ionization chamber is maintained at a pressure below atmospheric pressure, and a voltage difference is applied across the electrodes to induce a glow discharge between the electrodes, so that molecules passing through the inlet are ionized by the glow discharge and directed into the analyzer. The ionization source accepts the sample under atmospheric pressure conditions and processes it directly into the high vacuum instrument, bridging the pressure gap and drawing off unwanted atmospheric gases. The invention also includes a method for analyzing a gaseous sample using the glow discharge ionization source described above.

  15. Electrofuels: Tiny Organisms Making a Big Impact | Department of Energy

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

    Electrofuels: Tiny Organisms Making a Big Impact Electrofuels: Tiny Organisms Making a Big Impact February 16, 2012 - 12:30pm Addthis Electrofuels: Tiny Organisms Making a Big Impact Alexa McClanahan Communications Support Contractor to ARPA-E They say a picture is worth a thousand words - but what happens when what you want to look at is impossible to see? That's where the Advanced Research Projects Agency-Energy's Electrofuels program comes in. The 13 projects that make up the program seek to

  16. Tiny Particles with Big Magnetic Power | Argonne National Laboratory

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

    "Magnetic nanofibers" are special not only for their inherent properties as individual magnets, but also for their ability to be manipulated and deposited precisely to form novel materials. PDF icon tiny_magnetic_particles

  17. Nexus Energy Center Unveils Energy-Efficient Tiny Home

    Broader source: Energy.gov [DOE]

    Better Buildings Residential Network member Nexus Energy Center recently unveiled its first tiny, energy-efficient home. As previously reported, the nonprofit organization aimed to raise $5,000...

  18. Photo of the Week: Tiny Batteries | Department of Energy

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

    Tiny Batteries Photo of the Week: Tiny Batteries April 25, 2014 - 12:56pm Addthis For years, scientists have tracked the movements of salmon through rivers in the Pacific Northwest and around the world. Now a smaller, more powerful battery will allow them to track even younger, smaller fish over longer distances. Slightly larger than grains of rice, the new batteries power a transmitter small enough to inject into these fish -- rather than surgically implant them. The result is less stressful

  19. Glow discharge plasma deposition of thin films

    DOE Patents [OSTI]

    Weakliem, Herbert A. (Pennington, NJ); Vossen, Jr., John L. (Bridgewater, NJ)

    1984-05-29

    A glow discharge plasma reactor for deposition of thin films from a reactive RF glow discharge is provided with a screen positioned between the walls of the chamber and the cathode to confine the glow discharge region to within the region defined by the screen and the cathode. A substrate for receiving deposition material from a reactive gas is positioned outside the screened region. The screen is electrically connected to the system ground to thereby serve as the anode of the system. The energy of the reactive gas species is reduced as they diffuse through the screen to the substrate. Reactive gas is conducted directly into the glow discharge region through a centrally positioned distribution head to reduce contamination effects otherwise caused by secondary reaction products and impurities deposited on the reactor walls.

  20. An Innovative Pressure Sensor Glow Plug Offers Improved Diesel Engine

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

    Closed-loop Control | Department of Energy An Innovative Pressure Sensor Glow Plug Offers Improved Diesel Engine Closed-loop Control An Innovative Pressure Sensor Glow Plug Offers Improved Diesel Engine Closed-loop Control Describes glow plug with integrated pressure sensor for closed-loop control of diesel engine combustion PDF icon p-20_ramond.pdf More Documents & Publications Glow Plug Integrated Piezo-Ceramic Combustion Sensor for Diesel Engines Diesel Combustion Control with

  1. Curved track segment finding using Tiny Triplet Finder (TTF)

    SciTech Connect (OSTI)

    Wu, Jin-Yuan; Wang, M.; Gottschalk, E.; Shi, Z.; /Fermilab

    2006-11-01

    We describe the applications of a track segment recognition scheme called the Tiny Triplet Finder (TTF) that involves the grouping of three hits satisfying a constraint forming of a track segment. The TTF was originally developed solving straight track segment finding problem, however, it is also suitable in many curved track segment finding problems. The examples discussed in this document are among popular detector layouts in high-energy/nuclear physics experiments. Although it is not practical to find a universal recipe for arbitrary detector layouts, the method of the TTF application is illustrated via the discussion of the examples. Generally speaking, whenever the data item to be found in a pattern recognition problem contains two free parameters, and if the constraint connecting the measurements and the two free parameters has an approximate shift invariant property, the Tiny Triplet Finder can be used.

  2. Tiny travelers from deep space could assist in healing Fukushima's

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

    nuclear scar Fukushima Daiichi nuclear reactors Tiny travelers from deep space could assist in healing Fukushima's nuclear scar Researchers have devised a method to use cosmic rays to gather detailed information from inside the damaged cores of the Fukushima Daiichi nuclear reactors. October 17, 2012 Los Alamos National Laboratory Muon Radiography team members stand in front of the damaged Fukushima Daiichi reactor complex during a visit to determine evaluate whether Los Alamos' Scattering

  3. An Innovative Pressure Sensor Glow Plug Offers Improved Diesel...

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

    More Documents & Publications Glow Plug Integrated Piezo-Ceramic Combustion Sensor for Diesel Engines Diesel Combustion Control with Closed-Loop Control of the Injection Strategy ...

  4. Photo of the Week: Butterflies, Crystal Nanostructures and Solar Cell

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

    Research | Department of Energy What do butterflies and solar cell research have in common? Both have been developing tiny crystals that selectively reflect colors. Over millions of years of evolution, butterfly wings have developed the tiny crystal nanostructures that give butterflies their vivid colors. At Argonne National Laboratory, scientists are working to manufacture these crystals, which could one day be used to create "greener" and more efficient paints, fiber optics and

  5. Phenomena of oscillations in atmospheric pressure direct current glow discharges

    SciTech Connect (OSTI)

    Liu, Fu-cheng; Yan, Wen; Wang, De-zhen

    2013-12-15

    Self-sustained oscillations in a dc glow discharge with a semiconductor layer at atmospheric pressure were investigated by means of a one-dimensional fluid model. It is found that the dc glow discharge initially becomes unstable in the subnormal glow region and gives rise to oscillations of plasma parameters. A variety of oscillations with one or more frequencies have been observed under different conditions. The discharge oscillates between the glow discharge mode and the Townsend discharge mode in the oscillations with large amplitude while operates in the subnormal glow discharge mode all the while in the oscillations with small amplitude. Fourier Transform spectra of oscillations reveal the transition mechanism between different oscillations. The effects of semiconductor conductivity on the oscillation frequency of the dominant mode, gas voltage, as well as the discharge current have also been analyzed.

  6. Handling and characterization of glow-discharge polymer samples...

    Office of Scientific and Technical Information (OSTI)

    for the light gas gun Citation Details In-Document Search Title: Handling and characterization of glow-discharge polymer samples for the light gas gun Authors: Akin, M C ; ...

  7. A little drop will do it: Tiny grains of lithium can dramatically...

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

    A little drop will do it: Tiny grains of lithium can dramatically improve the performance of fusion plasmas By Raphael Rosen May 22, 2015 Tweet Widget Google Plus One Share on...

  8. Tiny Terminators: New Micro-Robots Assemble, Repair Themselves and Are Surprisingly Strong

    Broader source: Energy.gov [DOE]

    Tiny robots that can assemble and repair themselves? Watch a video of Argonne National Laboratory's micro-robots that easily perform tasks that can challenge other robots, including moving objects that are larger than themselves.

  9. Geek-Up[6.24.11]: Dust-sized 'Dragonfly' Device and Tiny Microvalves

    Broader source: Energy.gov [DOE]

    A dust-size "dragonfly-inspired" device -- which won a Sandia Lab design contest -- may ultimately enable the creation of tiny microvalves for experiments in biological research laboratories and medical facilities.

  10. Nexus Energy Center Raises Funds for Energy-Saving Tiny Home

    Broader source: Energy.gov [DOE]

    Nexus Energy Center, a Huntsville, Alabama-based Better Buildings Residential Network member, is trying to raise $5,000 through a crowd-funding effort to build the city’s first tiny, energy...

  11. Printing Tiny Batteries | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    "Printing" Tiny Batteries? Energy Frontier Research Centers (EFRCs) EFRCs Home Centers Research Science Highlights News & Events EFRC News EFRC Events DOE Announcements Publications History Contact BES Home 06.26.13 Stories of Discovery & Innovation: "Printing" Tiny Batteries? Print Text Size: A A A Subscribe FeedbackShare Page Researchers use sophisticated 3D printing techniques to create batteries the size of a grain of sand. This work, featured in the Office of

  12. "Printing" Tiny Batteries | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    "Printing" Tiny Batteries News News Home Featured Articles 2016 2015 2014 2013 2012 2011 2010 2009 2008 2007 2006 2005 Science Headlines Science Highlights Presentations & Testimony News Archives Communications and Public Affairs Contact Information Office of Science U.S. Department of Energy 1000 Independence Ave., SW Washington, DC 20585 P: (202) 586-5430 06.24.13 "Printing" Tiny Batteries Researchers use sophisticated 3D printing techniques to create batteries the size

  13. Extension of spatiotemporal chaos in glow discharge-semiconductor systems

    SciTech Connect (OSTI)

    Akhmet, Marat Fen, Mehmet Onur; Rafatov, Ismail

    2014-12-15

    Generation of chaos in response systems is discovered numerically through specially designed unidirectional coupling of two glow discharge-semiconductor systems. By utilizing the auxiliary system approach, [H. D. I. Abarbanel, N. F. Rulkov, and M. M. Sushchik, Phys. Rev. E 53, 45284535 (1996)] it is verified that the phenomenon is not a chaos synchronization. Simulations demonstrate various aspects of the chaos appearance in both drive and response systems. Chaotic control is through the external circuit equation and governs the electrical potential on the boundary. The expandability of the theory to collectives of glow discharge systems is discussed, and this increases the potential of applications of the results. Moreover, the research completes the previous discussion of the chaos appearance in a glow discharge-semiconductor system [D. D. ija?i? U. Ebert, and I. Rafatov, Phys. Rev. E 70, 056220 (2004).].

  14. Stratified-charge glow plug ignition engine experiments. Topical report

    SciTech Connect (OSTI)

    Thring, R.H.; Leet, J.A.

    1991-05-01

    An investigation was conducted to study the feasibility of operating a natural gas two-stroke engine using glow plug ignition with very lean mixtures. The term Stratified-Charge Glow Plus Ignition (SCGI) was coined to describe the engine. A JLO DL 365 single-cylinder, two-stroke, diesel engine was converted first to a natural gas fueled spark-ignited engine for the baseline tests, and then to the SCGI engine. The engine was successfully run, but was found to be sensitive to various conditions such as the glow plug temperature. The engine ran very lean, to an equivalence ratio of 0.33, offering the potential of good fuel economy and low NOx emissions. Numerous photographs, diagrams, and charts are included.

  15. ARC will make tiny "movies" of thermonuclear and stockpile experiments

    National Nuclear Security Administration (NNSA)

    | National Nuclear Security Administration will make tiny "movies" of thermonuclear and stockpile experiments | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing Our Infrastructure Countering Nuclear Terrorism About Our Programs Our History Who We Are Our Leadership Our Locations Budget Our Operations Library Bios Congressional

  16. NNSA & DOE Employees Use Tiny Smartphone Microscopes to Teach STEM |

    National Nuclear Security Administration (NNSA)

    National Nuclear Security Administration DOE Employees Use Tiny Smartphone Microscopes to Teach STEM | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing Our Infrastructure Countering Nuclear Terrorism About Our Programs Our History Who We Are Our Leadership Our Locations Budget Our Operations Library Bios Congressional Testimony Fact Sheets

  17. Sensitive glow discharge ion source for aerosol and gas analysis

    DOE Patents [OSTI]

    Reilly, Peter T. A. (Knoxville, TN)

    2007-08-14

    A high sensitivity glow discharge ion source system for analyzing particles includes an aerodynamic lens having a plurality of constrictions for receiving an aerosol including at least one analyte particle in a carrier gas and focusing the analyte particles into a collimated particle beam. A separator separates the carrier gas from the analyte particle beam, wherein the analyte particle beam or vapors derived from the analyte particle beam are selectively transmitted out of from the separator. A glow discharge ionization source includes a discharge chamber having an entrance orifice for receiving the analyte particle beam or analyte vapors, and a target electrode and discharge electrode therein. An electric field applied between the target electrode and discharge electrode generates an analyte ion stream from the analyte vapors, which is directed out of the discharge chamber through an exit orifice, such as to a mass spectrometer. High analyte sensitivity is obtained by pumping the discharge chamber exclusively through the exit orifice and the entrance orifice.

  18. The Use of DC Glow Discharges as Undergraduate Educational Tools

    Office of Scientific and Technical Information (OSTI)

    25 PPPL- 4825 The Use of DC Glow Discharges as Undergraduate Educational Tools October, 2012 Stephanie A. Wissel, Andrew Zwicker, Jerry Ross and Sophia Gershman Princeton Plasma Physics Laboratory Report Disclaimers Full Legal Disclaimer This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, nor any of their contractors, subcontractors or their employees, makes

  19. The Use of DC Glow Discharges as Undergraduate Educational Tools

    SciTech Connect (OSTI)

    Stephanie A. Wissel and Andrew Zwicker, Jerry Ross, and Sophia Gershman

    2012-10-09

    Plasmas have a beguiling way of getting students excited and interested in physics. We argue that plasmas can and should be incorporated into the undergraduate curriculum as both demonstrations and advanced investigations of electromagnetism and quantum effects. Our device, based on a direct current (DC) glow discharge tube, allows for a number of experiments into topics such as electrical breakdown, spectroscopy, magnetism, and electron temperature.

  20. Glow Plug Integrated Piezo-Ceramic Combustion Sensor for Diesel Engines |

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

    Department of Energy Glow Plug Integrated Piezo-Ceramic Combustion Sensor for Diesel Engines Glow Plug Integrated Piezo-Ceramic Combustion Sensor for Diesel Engines 2005 Diesel Engine Emissions Reduction (DEER) Conference Presentations and Posters PDF icon 2005_deer_troy.pdf More Documents & Publications An Innovative Pressure Sensor Glow Plug Offers Improved Diesel Engine Closed-loop Control Vehicle Technologies Office: 2013 Propulsion Materials R&D Annual Progress Report Complete

  1. Electronic and structural influence of Ni by Pd substitution on the hydrogenation properties of TiNi

    SciTech Connect (OSTI)

    Emami, Hoda; Souques, Raphaeel; Crivello, Jean-Claude; Cuevas, Fermin

    2013-02-15

    In Ti (Ni,Pd) compounds, the hydrogen capacity and the stability of their hydrides decreases when Ni is partially substituted by larger in size Pd atoms. To understand this peculiar behaviour, the crystal structure of TiNi{sub 1-x}Pd{sub x}D{sub y} (x=0.1, 0.3 and 0.5) deuterides and the stability of TiNi{sub 1-x}Pd{sub x} (0{<=}x{<=}0.5) intermetallics and their hydrides have been investigated by both neutron diffraction experiments and Density Functional Theory (DFT) calculations. Neutron diffraction shows that at x=0.1 and 0.3, deuterium absorption induces tetragonal distortion in intermetallics sublattice whereas at x=0.5 the cubic symmetry is preserved. The structural properties and the heat of formation of TiNi{sub 1-x}Pd{sub x} (0{<=}x{<=}0.5) intermetallics and their hydrides have been determined by DFT. These results show that Pd substitution increases the stability of the intermetallics and decreases the stability of the hydrides, which confirms the rule of reverse stability. - Graphical abstract: Crystal structure of Ti(Ni,Pd)Hy hydrides in the I4/mmm space group. Highlights: Black-Right-Pointing-Pointer Neutron Diffraction and DFT calculations have been done on TiNi{sub 1-x}Pd{sub x}H{sub y} compounds. Black-Right-Pointing-Pointer Electronic effect of Pd substitution governs the hydrogenation properties in TiNi. Black-Right-Pointing-Pointer The rule of reverse stability in intermetallics/hydrides is observed with Pd substitution. Black-Right-Pointing-Pointer The hydrogen atoms in the I4/mmm structure prefer to occupy the 16n site.

  2. Novel Enzyme from Tiny Gribble Could Prove a Boon for Biofuels Research -

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

    News Releases | NREL Novel Enzyme from Tiny Gribble Could Prove a Boon for Biofuels Research Wood borer makes its own enzyme, which could thrive in industrial setting June 11, 2013 Researchers from the United Kingdom, the Energy Department's National Renewable Energy Laboratory (NREL), and the University of Kentucky have recently published a paper describing a novel cellulose-degrading enzyme from a marine wood borer Limnoria quadripunctata, commonly known as the gribble. Gribbles are

  3. Discovered: Tiny Drops of "Perfect" Fluid that Existed in the Early

    Office of Science (SC) Website

    Universe | U.S. DOE Office of Science (SC) Discovered: Tiny Drops of "Perfect" Fluid that Existed in the Early Universe Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Funding Opportunities Nuclear Science Advisory Committee (NSAC) Community Resources Contact Information Nuclear Physics U.S. Department of Energy SC-26/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3613 F: (301) 903-3833 E: Email Us More

  4. Intense X-rays expose tiny flaws in 3-D printed titanium that can lead to

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

    breakage over time | Argonne National Laboratory Intense X-rays expose tiny flaws in 3-D printed titanium that can lead to breakage over time By Katie Elyce Jones * March 4, 2016 Tweet EmailPrint Titanium is strong but light - a desirable property among metals. In the twentieth century, titanium was used in military aircraft and equipment and commercial jets. Today, we find this tough and flexible metal all around us - in sports gear, tools, surgical and dental implants, prosthetics,

  5. LANL Transfers Glowing Bio Technology to Sandia Biotech

    ScienceCinema (OSTI)

    Rorick, Kevin

    2012-08-02

    Partnering with Los Alamos National Laboratory, an Albuquerque-based company is seeking to transform the way protein and peptide analysis is conducted around the world. Sandia Biotech is using a biological technology licensed from Los Alamos called split green fluorescent protein (sGFP), as a detecting and tracking tool for the protein and peptide industry, valuable in the fields of Alzheimer's research, drug development and other biotechnology fields using protein folding to understand protein expression and mechanisms of action. http://www.lanl.gov/news/stories/glowing-future-for-los-alamos-and-sandia-b iotech-partnership.html

  6. LANL Transfers Glowing Bio Technology to Sandia Biotech

    SciTech Connect (OSTI)

    Rorick, Kevin

    2012-01-01

    Partnering with Los Alamos National Laboratory, an Albuquerque-based company is seeking to transform the way protein and peptide analysis is conducted around the world. Sandia Biotech is using a biological technology licensed from Los Alamos called split green fluorescent protein (sGFP), as a detecting and tracking tool for the protein and peptide industry, valuable in the fields of Alzheimer's research, drug development and other biotechnology fields using protein folding to understand protein expression and mechanisms of action. http://www.lanl.gov/news/stories/glowing-future-for-los-alamos-and-sandia-b iotech-partnership.html

  7. Reproducing continuous radio blackout using glow discharge plasma

    SciTech Connect (OSTI)

    Xie, Kai; Li, Xiaoping; Liu, Donglin; Shao, Mingxu [School of Aerospace Science and Technology, Xidian University, Xi'an 710071 (China)] [School of Aerospace Science and Technology, Xidian University, Xi'an 710071 (China); Zhang, Hanlu [School of Communication and Information Engineering, Xi'an University of Posts and Telecommunications, Xi'an 710121 (China)] [School of Communication and Information Engineering, Xi'an University of Posts and Telecommunications, Xi'an 710121 (China)

    2013-10-15

    A novel plasma generator is described that offers large-scale, continuous, non-magnetized plasma with a 30-cm-diameter hollow structure, which provides a path for an electromagnetic wave. The plasma is excited by a low-pressure glow discharge, with varying electron densities ranging from 10{sup 9} to 2.5 10{sup 11} cm{sup ?3}. An electromagnetic wave propagation experiment reproduced a continuous radio blackout in UHF-, L-, and S-bands. The results are consistent with theoretical expectations. The proposed method is suitable in simulating a plasma sheath, and in researching communications, navigation, electromagnetic mitigations, and antenna compensation in plasma sheaths.

  8. Ocean Viruses: Tiny entities with Global Impacts ( JGI Seventh Annual User Meeting 2012: Genomics of Energy and Environment)

    ScienceCinema (OSTI)

    Sullivan, Matthew B [University of Arizona

    2013-01-15

    Matt Sullivan from the University of Arizona on "Ocean Viruses: Tiny Entities with Global Impacts" at the 7th Annual Genomics of Energy & Environment Meeting on March 22, 2012 in Walnut Creek, Calif.

  9. Ocean Viruses: Tiny entities with Global Impacts ( JGI Seventh Annual User Meeting 2012: Genomics of Energy and Environment)

    SciTech Connect (OSTI)

    Sullivan, Matthew B [University of Arizona] [University of Arizona

    2012-03-22

    Matt Sullivan from the University of Arizona on "Ocean Viruses: Tiny Entities with Global Impacts" at the 7th Annual Genomics of Energy & Environment Meeting on March 22, 2012 in Walnut Creek, Calif.

  10. COMPOSITION AND STRUCTURAL STUDIES OF STRONG GLOW DISCHARGE POLYMER COATINGS

    SciTech Connect (OSTI)

    CZECHOWICZ, DG; CASTILLO, ER; NIKROO, A

    2002-04-01

    OAK A271 COMPOSITION AND STRUCTURAL STUDIES OF STRONG GLOW DISCHARGE POLYMER COATINGS. An investigation of the chemical composition and structure of strong glow discharge (GDP) polymer shells made for cryogenic experiments at OMEGA is described. The investigation was carried out using combustion and Fourier Transform Infrared Spectroscopy (FTIR) analysis. The strongest coatings were observed to have the lowest hydrogen content or hydrogen/carbon H/C ratio, whereas the weakest coatings had the highest hydrogen content or H/C ratio. Chemical composition results from combustion were used to complement FTIR analysis to determine the relative hydrogen content of as-fabricated coatings. Good agreement was observed between composition results obtained from combustion and FTIR analysis. FTIR analysis of coating structures showed the strongest coatings to have less terminal methyl groups and a more double bond or olefinic structure. Strong GDP coatings that were aged in air react more with oxygen and moisture than standard GDP coatings. In addition to a more olefinic structure, there may also be more free-radial sites present in strong GDP coatings, which leads to greater oxygen uptake.

  11. A little drop will do it: Tiny grains of lithium can dramatically improve

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

    the performance of fusion plasmas | Princeton Plasma Physics Lab A little drop will do it: Tiny grains of lithium can dramatically improve the performance of fusion plasmas By Raphael Rosen May 22, 2015 Tweet Widget Google Plus One Share on Facebook Left: DIII-D tokamak. Right: Cross-section of plasma in which lithium has turned the emitted light green. (Credits: Left, General Atomics / Right, Steve Allen, Lawrence Livermore National Laboratory) Left: DIII-D tokamak. Right: Cross-section of

  12. A little drop will do it: Tiny grains of lithium can dramatically improve

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

    the performance of fusion plasmas | Princeton Plasma Physics Lab A little drop will do it: Tiny grains of lithium can dramatically improve the performance of fusion plasmas By Raphael Rosen May 22, 2015 Tweet Widget Google Plus One Share on Facebook Left: DIII-D tokamak. Right, Cross-section of plasma in which lithium has turned the emitted light green. (Credits: Left, General Atomics / Right: Steve Allen, Lawrence Livermore National Laboratory) Left: DIII-D tokamak. Right, Cross-section of

  13. Flush-mounted probe diagnostics for argon glow discharge plasma

    SciTech Connect (OSTI)

    Xu, Liang Cao, Jinxiang; Liu, Yu; Wang, Jian; Du, Yinchang; Zheng, Zhe; Zhang, Xiao; Wang, Pi; Zhang, Jin; Li, Xiao; Qin, Yongqiang; Zhao, Liang

    2014-09-15

    A comparison is made between plasma parameters measured by a flush-mounted probe (FP) and a cylindrical probe (CP) in argon glow discharge plasma. Parameters compared include the space potential, the plasma density, and the effective electron temperature. It is found that the ion density determined by the FP agrees well with the electron density determined by the CP in the quasi-neutral plasma to better than 10%. Moreover, the space potential and effective electron temperature calculated from electron energy distribution function measured by the FP is consistent with that measured by the CP over the operated discharge current and pressure ranges. These results present the FP can be used as a reliable diagnostic tool in the stable laboratory plasma and also be anticipated to be applied in other complicated plasmas, such as tokamaks, the region of boundary-layer, and so on.

  14. Plasma stability control using dielectric barriers in radio-frequency atmospheric pressure glow discharges

    SciTech Connect (OSTI)

    Shi, J. J.; Liu, D. W.; Kong, M. G.

    2006-08-21

    It is widely accepted that electrode insulation is unnecessary for generating radio-frequency (rf) atmospheric pressure glow discharges (APGDs). It is also known that rf APGDs with large discharge current are susceptible to the glow-to-arc transition. In this letter, a computational study is presented to demonstrate that dielectric barriers provide an effective control over unlimited current growth and allow rf APGDs to be operated at very high current densities with little danger of the glow-to-arc transition. Characteristics of electrode sheaths are used to show that the stability control is achieved by forcing the plasma-containing electrode unit to acquire positive differential conductivity.

  15. Note: Rapid reduction of graphene oxide paper by glow discharge plasma

    SciTech Connect (OSTI)

    Bo, Zheng; Qian, Jiajing; Duan, Liangping; Qiu, Kunzan Yan, Jianhua; Cen, Kefa; Han, Zhao Jun; Ostrikov, Kostya

    2015-05-15

    This note reports on a novel method for the rapid reduction of graphene oxide (GO) paper using a glow discharge plasma reactor. Glow discharge is produced and sustained between two parallel-plate graphite electrodes at a pressure of 240 mTorr. By exposing GO paper at the junction of negative-glow and Faraday-dark area for 4 min, the oxygen-containing groups can be effectively removed (C/O ratio increases from 2.6 to 7.9), while the material integrality and flexibility are kept well. Electrochemical measurements demonstrate that the as-obtained reduced GO paper can be potentially used for supercapacitor application.

  16. Trace elements in coal by glow discharge mass spectrometry

    SciTech Connect (OSTI)

    Jacobs, M.L.; Wilson, C.R.; Pestovich, J. Jr.

    1995-08-01

    A need and a demand exist for determining trace elements in coal and coal related by-products, especially those elements which may potentially be a health hazard. The provisions of the 1990 clean air act require that the EPA evaluate the emissions of electric utilities for trace elements and other potentially hazardous organic compounds. The coal fired electric utility industry supplies roughly 60% of the total generating capacity of 2,882,525 million kilowatt hours (nearly 3 trillion kilowatt hours) generated in the U.S. This is accomplished by 414 power plants scattered across the country that burned 813,508,000 short tons of coal in 1993. The relative volatility of some inorganic constituents in coal makes them more prone to be emitted to the atmosphere following combustion. The production of analytical data for trace elements is known to be a difficult task in coal and by-products of coal combustion (fly ash, bottom ash, gas streams, etc.), in terms of both sample collection and analytical determinations. There are several common analytical methods available to the analyst to determine trace elements in coal and coal by-products. In general analytical germs, the material to be analyzed can be totally solubilized (or extracted), or the elements analytes can be determined in the material as a solid. A relatively new elemental technique, Glow Discharge Mass Spectrometry (GDMS) can be used with solids as well. This new analytical technique had never before been applied directly to coal. The radio frequency-glow discharge quadropole mass spectrometer was used to analyze coal directly for the first time ever by rf-GDMS. The rf-GDMS technique is described.

  17. Dynamics of multiple double layers in high pressure glow discharge in a simple torus

    SciTech Connect (OSTI)

    Kumar Paul, Manash, E-mail: manashkr@gmail.com [Department of Physics, National Institute of Technology Agartala, Tripura799 046 (India); Sharma, P. K.; Thakur, A.; Kulkarni, S. V.; Bora, D. [Institute for Plasma Research, Bhat, Gandhinagar, Gujarat382 428 (India)

    2014-06-15

    Parametric characterization of multiple double layers is done during high pressure glow discharge in a toroidal vessel of small aspect ratio. Although glow discharge (without magnetic field) is known to be independent of device geometry, but the toroidal boundary conditions are conducive to plasma growth and eventually the plasma occupy the toroidal volume partially. At higher anode potential, the visibly glowing spots on the body of spatially extended anode transform into multiple intensely luminous spherical plasma blob structures attached to the tip of the positive electrode. Dynamics of multiple double layers are observed in argon glow discharge plasma in presence of toroidal magnetic field. The radial profiles of plasma parameters measured at various toroidal locations show signatures of double layer formation in our system. Parametric dependence of double layer dynamics in presence of toroidal magnetic field is presented here.

  18. Binary and ternary gas mixtures for use in glow discharge closing switches

    DOE Patents [OSTI]

    Hunter, Scott R. (Oak Ridge, TN); Christophorou, Loucas G. (Oak Ridge, TN)

    1990-01-01

    Highly efficient binary and ternary gas mixtures for use in diffuse glow discharge closing switches are disclosed. The binary mixtures are combinations of helium or neon and selected perfluorides. The ternary mixtures are combinations of helium, neon, or argon, a selected perfluoride, and a small amount of gas that exhibits enhanced ionization characteristics. These mixtures are shown to be the optimum choices for use in diffuse glow discharge closing switches by virtue of the combined physio-electric properties of the mixture components.

  19. Ambient-atmosphere glow discharge for determination of elemental concentration in solutions in a high-throughput or transient fashion

    DOE Patents [OSTI]

    Webb, Michael R. (Somerville, MA); Hieftje, Gary M. (Bloomington, IN); Andrade, Francisco (Leeds, GB)

    2011-04-19

    An ambient atmosphere glow discharge spectrometer is disclosed having a capillary, two electrodes and a means for recording the atomic emissions.

  20. Binary and ternary gas mixtures with temperature enhanced diffuse glow discharge characteristics for use in closing switches

    DOE Patents [OSTI]

    Christophorou, Loucas G. (Oak Ridge, TN); Hunter, Scott R. (Oak Ridge, TN)

    1990-01-01

    An improvement to the gas mixture used in diffuse glow discharge closing switches is disclosed which includes binary and ternary gas mixtures which are formulated to exhibit decreasing electron attachment with increasing temperature. This increases the efficiency of the conductance of the glow discharge and further inhibits the formation of an arc.

  1. Binary and ternary gas mixtures with temperature enhanced diffuse glow discharge characteristics for use in closing switches

    DOE Patents [OSTI]

    Christophorou, L.G.; Hunter, S.R.

    1990-06-26

    An improvement to the gas mixture used in diffuse glow discharge closing switches is disclosed which includes binary and ternary gas mixtures which are formulated to exhibit decreasing electron attachment with increasing temperature. This increases the efficiency of the conductance of the glow discharge and further inhibits the formation of an arc. 11 figs.

  2. Binary and ternary gas mixtures with temperature enhanced diffuse glow discharge characteristics for use in closing switches

    DOE Patents [OSTI]

    Christophorou, L.G.; Hunter, S.R.

    1988-06-28

    An improvement to the gas mixture used in diffuse glow discharge closing switches is disclosed which includes binary and ternary gas mixtures which are formulated to exhibit decreasing electron attachment with increasing temperature. This increases the efficiency of the conductance of the glow discharge and further inhibits the formation of an arc. 11 figs.

  3. Binary and ternary gas mixtures for use in glow discharge closing switches

    DOE Patents [OSTI]

    Hunter, S.R.; Christophorou, L.G.

    1988-04-27

    Highly efficient binary and ternary gas mixtures for use in diffuse glow discharge closing switches are disclosed. The binary mixtures are combinations of helium or neon and selected perfluorides. The ternary mixtures are combinations of helium, neon, or argon, a selected perfluoride, and a small amount of gas that exhibits enhanced ionization characteristics. These mixtures are shown to be the optimum choices for use in diffuse glow discharge closing switches by virtue if the combines physio-electric properties of the mixture components. 9 figs.

  4. Detrapping of tungsten nanoparticles in a direct-current argon glow discharge

    SciTech Connect (OSTI)

    Coudel, L. Kumar, K. Kishor; Arnas, C.

    2014-12-15

    Nanoparticles are grown from the sputtering of a tungsten cathode in a direct current argon glow discharge. Laser light scattering of a vertical laser sheet going through the plasma reveals that the dust particle cloud is compressed and pushed towards the anode during the discharge. Scanning electron microscopy images of substrates exposed to the plasma for given durations show that dust particles are continuously falling down on the anode during the discharge. These observations are explained by the fact that the electrostatic force at the negative glow-anode sheath boundary cannot balance the ion drag, gravity, and thermophoresis forces for particles of more than a few tens of nanometres in diameter.

  5. Effect of Cu addition on the martensitic transformation of powder metallurgy processed TiNi alloys

    SciTech Connect (OSTI)

    Kim, Yeon-wook; Choi, Eunsoo

    2014-10-15

    Highlights: M{sub s} of Ti{sub 50}Ni{sub 50} powders is 22 C, while M{sub s} of SPS-sintered porous bulk increases up to 50 C. M{sub s} of Ti{sub 50}Ni{sub 40}Cu{sub 20} porous bulk is only 2 C higher than that of the powders. Recovered stain of porous TiNi and TiNiCu alloy is more than 1.5%. - Abstract: Ti{sub 50}Ni{sub 50} and Ti{sub 50}Ni{sub 30}Cu{sub 20} powders were prepared by gas atomization and their transformation behaviors were examined by means of differential scanning calorimetry and X-ray diffraction. One-step B2B19 transformation occurred in Ti{sub 50}Ni{sub 50} powders, while Ti{sub 50}Ni{sub 30}Cu{sub 20} powders showed B2B19 transformation behavior. Porous bulks with 24% porosity were fabricated by spark plasma sintering. The martensitic transformation start temperature (50 C) of Ti{sub 50}Ni{sub 50} porous bulk is much higher than that (22 C) of the as-solidified powders. However, the martensitic transformation start temperature (35 C) of Ti{sub 50}Ni{sub 30}Cu{sub 20} porous bulk is almost the same as that (33 C) of the powders. When the specimens were compressed to the strain of 8% and then unloaded, the residual strains of Ti{sub 50}Ni{sub 50} and Ti{sub 50}Ni{sub 30}Cu{sub 20} alloy bulks were 3.95 and 3.7%, respectively. However, these residual strains were recovered up to 1.7% after heating by the shape memory phenomenon.

  6. Simulation Study of an Extended Density DC Glow Toroidal Plasma Source

    SciTech Connect (OSTI)

    Granda-Gutierrez, E. E.; Piedad-Beneitez, A. de la; Lopez-Callejas, R.; Godoy-Cabrera, O. G.; Benitez-Read, J. S.; Pacheco-Sotelo, J. O.; Pena-Eguiluz, R.; Mercado-Cabrera, A.; Valencia A, R.; Barocio, S. R.

    2006-12-04

    Conventional wisdom assigns the DC glow discharge regime to plasma currents below {approx}500 mA values, beyond which the discharge falls into the anomalous glow and the turbulent arc regimes. However, we have found evidence that, during toroidal discharges, this barrier can be ostensibly extended up to 800 mA. Thus, a computer simulation has been applied to the evolution of the main electrical characteristics of such a glow discharge plasma in a toroidal vessel in order to design and construct a respective voltage/current controlled source. This should be able to generate a DC plasma in the glow regime with which currents in the range 10-3-100 A can be experimented and 109-1010 cm-3 plasma densities can be achieved to PIII optimization purposes. The plasma is modelled as a voltage-controlled current source able to be turned on whenever the breakdown voltage is reached across the gap between the anode and the vessel wall. The simulation outcome fits well our experimental measurements showing that the plasma current obeys power laws that are dependent on the power current and other control variables such as the gas pressure.

  7. High explosives vapor detection by atmospheric sampling glow discharge ionization/tandem mass spectrometry

    SciTech Connect (OSTI)

    McLuckey, S.A.; Goeringer, D.E.; Asano, K.G.

    1996-02-01

    The combination of atmospheric sampling glow discharge ionization with tandem mass spectrometry for the detection of traces of high explosives is described. Particular emphasis is placed on use of the quadrupole ion trap as the type of tandem mass spectrometer. Atmospheric sampling glow discharge provides a simple, rugged, and efficient means for anion formation while the quadrupole ion trap provides for efficient tandem mass spectrometry. Mass selective ion accumulation and non-specific ion activation methods can be used to overcome deleterious effects arising from ion/ion interactions. Such interactions constitute the major potential technical barrier to the use of the ion trap for real-time monitoring of targeted compounds in uncontrolled and highly variable matrices. Tailored waveforms can be used to effect both mass selective ion accumulation and ion activation. Concatenated tailored waveforms allow for both functions in a single experiment thereby providing the capability for monitoring several targeted species simultaneously. The combination of atmospheric sampling glow discharge ionization with a state-of-the-art analytical quadrupole ion trap is a highly sensitive and specific detector for traces of high explosives. The combination is also small and inexpensive relative to virtually any other form of tandem mass spectrometry. The science and technology underlying the glow discharge/ion trap combination is sufficiently mature to form the basis for an engineering effort to make the detector portable. 85 refs.

  8. Isotope effects on desorption kinetics of hydrogen isotopes implanted into stainless steel by glow discharge

    SciTech Connect (OSTI)

    Matsuyama, M.; Kondo, M.; Noda, N.; Tanaka, M.; Nishimura, K.

    2015-03-15

    In a fusion device the control of fuel particles implies to know the desorption rate of hydrogen isotopes by the plasma-facing materials. In this paper desorption kinetics of hydrogen isotopes implanted into type 316L stainless steel by glow discharge have been studied by experiment and numerical calculation. The temperature of a maximum desorption rate depends on glow discharge time and heating rate. Desorption spectra observed under various experimental conditions have been successfully reproduced by numerical simulations that are based on a diffusion-limited process. It is suggested, therefore, that desorption rate of a hydrogen isotope implanted into the stainless steel is limited by a diffusion process of hydrogen isotope atoms in bulk. Furthermore, small isotope effects were observed for the diffusion process of hydrogen isotope atoms. (authors)

  9. Development of all-ceramic glow plugs for heavy-duty engines: Phase 2

    SciTech Connect (OSTI)

    Johar, S.; Das Gupta, S.

    1997-12-31

    Details the development work performed in phase 2 of a project to develop all-ceramic glow plugs for heavy-duty diesel engines. All-ceramic glow plugs, compared to traditional metallic plugs, offer a number of advantages including high corrosion resistance, operation at higher temperatures allowing for quicker start and improved engine performance, low power use, high dimensional stability, and longer service life. Work in phase 2 focused on increasing the operational voltage ratings of the proof-of-concept plugs developed in phase 1 in order to meet all commercial expectations in terms of performance, reliability, durability, and economic manufacture. The work involved optimization of the material composition to meet design specifications, development of a manufacturing process, fabrication of plugs, and bench and engine tests. Results compare the all-ceramic plugs to conventional plugs.

  10. Investigation of reports of fusion reactions occurring at the cathode in glow discharges

    SciTech Connect (OSTI)

    Ellison, C.H.; Mahaffey, J.A.

    1996-01-01

    Recent reports of deuteron-deuteron (d-d) neutrons resulting from nuclear reactions in or at the palladium cathode of a deuterium glow discharge were investigated. The equipment, techniques, and experimental procedures are discussed in detail, as well as various possible mechanisms to produce such reactions. The results of this investigation do not confirm the presence of d-d reactions. 15 refs., 9 figs.

  11. Producing a Radioactive Source in a Deuterated Palladium Electrode Under Direct-Current Glow Discharge

    SciTech Connect (OSTI)

    Yamada, Hiroshi; Uchiyama, Kazuyoshi; Kawata, Nobuhiko; Kurisawa, Yoshiyuki; Nakamura, Mitsuru

    2001-03-15

    Anomalous gamma emission was rarely observed during direct-current glow discharge in {approx}3 Torrs of deuterium gas using a deuterated palladium foil cathode. Autoradiography after the discharge experiment showed that isotopes with low- and high-energy radiation components were produced before or during the discharge. The palladium foil after the anomalous gamma-ray emission was analyzed by secondary ion mass spectroscopy, which revealed a considerable increase in the content of iron and copper on the surface.

  12. A comparison of hydrogen vs. helium glow discharge effects on fusion device first-wall conditioning

    SciTech Connect (OSTI)

    Dylla, H.F.

    1989-09-01

    Hydrogen- and deuterium-fueled glow discharges are used for the initial conditioning of magnetic fusion device vacuum vessels following evacuation from atmospheric pressure. Hydrogenic glow discharge conditioning (GDC) significantly reduces the near-surface concentration of simple adsorbates, such as H/sub 2/O, CO, and CH/sub 4/, and lowers ion-induced desorption coefficients by typically three orders of magnitude. The time evolution of the residual gas production observed during hydrogen-glow discharge conditioning of the carbon first-wall structure of the TFTR device is similar to the time evolution observed during hydrogen GDC of the initial first-wall configuration in TFTR, which was primarily stainless steel. Recently, helium GDC has been investigated for several wall-conditioning tasks on a number of tokamaks including TFTR. Helium GDC shows negligible impurity removal with stainless steel walls. For impurity conditioning with carbon walls, helium GDC shows significant desorption of H/sub 2/O, CO, and CO/sub 2/; however, the total desorption yield is limited to the monolayer range. In addition, helium GDC can be used to displace hydrogen isotopes from the near-surface region of carbon first-walls in order to lower hydrogenic retention and recycling. 38 refs., 6 figs.

  13. Mechanism behind self-sustained oscillations in direct current glow discharges and dusty plasmas

    SciTech Connect (OSTI)

    Cho, Sung Nae

    2013-04-15

    An alternative explanation to the mechanism behind self-sustained oscillations of ions in direct current (DC) glow discharges is provided. Such description is distinguished from the one provided by the fluid models, where oscillations are attributed to the positive feedback mechanism associated with photoionization of particles and photoemission of electrons from the cathode. Here, oscillations arise as consequence of interaction between an ion and the surface charges induced by it at the bounding electrodes. Such mechanism provides an elegant explanation to why self-sustained oscillations occur only in the negative resistance region of the voltage-current characteristic curve in the DC glow discharges. Furthermore, this alternative description provides an elegant explanation to the formation of plasma fireballs in the laboratory plasma. It has been found that oscillation frequencies increase with ion's surface charge density, but at the rate which is significantly slower than it does with the electric field. The presented mechanism also describes self-sustained oscillations of ions in dusty plasmas, which demonstrates that self-sustained oscillations in dusty plasmas and DC glow discharges involve common physical processes.

  14. Irregular-regular-irregular mixed mode oscillations in a glow discharge plasma

    SciTech Connect (OSTI)

    Ghosh, Sabuj Shaw, Pankaj Kumar Saha, Debajyoti Janaki, M. S. Iyengar, A. N. Sekar

    2015-05-15

    Floating potential fluctuations of a glow discharge plasma are found to exhibit different kinds of mixed mode oscillations. Power spectrum analysis reveals that with change in the nature of the mixed mode oscillation (MMO), there occurs a transfer of power between the different harmonics and subharmonics. The variation in the chaoticity of different types of mmo was observed with the study of Lyapunov exponents. Estimates of correlation dimension and the Hurst exponent suggest that these MMOs are of low dimensional nature with an anti persistent character. Numerical modeling also reflects the experimentally found transitions between the different MMOs.

  15. Surface oxygen micropatterns on glow discharge polymer targets by photo irradiation

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

    Reynolds, Hannah; Baxamusa, Salmaan; Haan, Steven W.; Fitzsimmons, Paul; Carlson, Lane; Farrell, Mike; Nikroo, Abbas; Watson, Brian J.

    2016-02-24

    Recent simulations predict surface oxygen may be a significant source of disruptive perturbations in the implosion process of glow-discharge polymers (GDP) ablators at the National Ignition Facility. GDP material held in ambient atmospheric conditions showed an increase in mass when stored in light transparent containers, which suggests that photo exposure is a driving force for oxygen absorption. To investigate if surface oxygen is a contributing factor of disruptive perturbations during implosion, we developed a method to imprint a periodic micropattern of oxygen on the surface of GDP and used it to fabricate a flat sample for empirical testing.

  16. Nonlocal control of electron temperature in short direct current glow discharge plasma

    SciTech Connect (OSTI)

    Demidov, V. I.; Kudryavtsev, A. A.; Stepanova, O. M.; Kurlyandskaya, I. P.

    2014-09-15

    To demonstrate controlling the electron temperature in nonlocal plasma, experiments have been performed on a short (without positive column) dc glow discharge with a cold cathode by applying different voltages to the conducting discharge wall. The experiments have been performed for low-pressure noble gas discharges. The applied voltage can modify trapping the energetic electrons emitted from the cathode sheath and arising from the atomic and molecular processes in the plasma within the device volume. This phenomenon results in the energetic electrons heating the slow plasma electrons, which consequently modifies the electron temperature. Furthermore, a numerical model of the discharge has demonstrated the electron temperature modification for the above case.

  17. On the physical processes ruling an atmospheric pressure air glow discharge operating in an intermediate current regime

    SciTech Connect (OSTI)

    Prevosto, L. Mancinelli, B.; Chamorro, J. C.; Cejas, E.; Kelly, H.

    2015-02-15

    Low-frequency (100?Hz), intermediate-current (50 to 200?mA) glow discharges were experimentally investigated in atmospheric pressure air between blunt copper electrodes. Voltagecurrent characteristics and images of the discharge for different inter-electrode distances are reported. A cathode-fall voltage close to 360?V and a current density at the cathode surface of about 11?A/cm{sup 2}, both independent of the discharge current, were found. The visible emissive structure of the discharge resembles to that of a typical low-pressure glow, thus suggesting a glow-like electric field distribution in the discharge. A kinetic model for the discharge ionization processes is also presented with the aim of identifying the main physical processes ruling the discharge behavior. The numerical results indicate the presence of a non-equilibrium plasma with rather high gas temperature (above 4000?K) leading to the production of components such as NO, O, and N which are usually absent in low-current glows. Hence, the ionization by electron-impact is replaced by associative ionization, which is independent of the reduced electric field. This leads to a negative current-voltage characteristic curve, in spite of the glow-like features of the discharge. On the other hand, several estimations show that the discharge seems to be stabilized by heat conduction; being thermally stable due to its reduced size. All the quoted results indicate that although this discharge regime might be considered to be close to an arc, it is still a glow discharge as demonstrated by its overall properties, supported also by the presence of thermal non-equilibrium.

  18. Influences of impedance matching network on pulse-modulated radio frequency atmospheric pressure glow discharges

    SciTech Connect (OSTI)

    Huo, W. G. [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116023 (China); School of Physics and Electronic Technology, Liaoning Normal University, Dalian 116029 (China); Xu, K.; Sun, B.; Ding, Z. F. [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116023 (China)

    2012-08-15

    Pulse-modulated RF atmospheric pressure glow discharges (APDGs) were investigated in recent years to reduce the thermal accumulation and extend the operation region of the stable alpha glow mode. Different pulse-modulated voltage and current waveforms were acquired in previous experiments, but no attention was paid to the interpretation. We investigated this issue and associated phenomenon via positive and negative feedback effects derived from varying the series capacitor in the inversely L-shaped matching network used in our pulse-modulated RF APGD source. The evolutions of pulse-modulated RF waveforms were found to be associated with the feedback region and the pulsed plasma absorbed RF power. In the positive feedback region, pulse-modulated RF APGDs are relatively stable. In the negative feedback region, wide spikes as well as undershoots occur in RF voltage and current waveforms and the plasma absorbed RF power. In case of a high RF power discharge with a low modulation frequency, the pulse-modulated RF APGD is extinguished and re-ignited due to the enhanced undershoot during the initial pulse phase. The pulse-modulated RF APGD can transit from positive to negative feedback region in a range of series capacitance. Experimental results are discussed by the aid of equivalent circuit, negative and positive feedback effects.

  19. Radio-frequency powered glow discharge device and method with high voltage interface

    DOE Patents [OSTI]

    Duckworth, Douglas C.; Marcus, R. Kenneth; Donohue, David L.; Lewis, Trousdale A.

    1994-01-01

    A high voltage accelerating potential, which is supplied by a high voltage direct current power supply, is applied to the electrically conducting interior wall of an RF powered glow discharge cell. The RF power supply desirably is electrically grounded, and the conductor carrying the RF power to the sample held by the probe is desirably shielded completely excepting only the conductor's terminal point of contact with the sample. The high voltage DC accelerating potential is not supplied to the sample. A high voltage capacitance is electrically connected in series between the sample on the one hand and the RF power supply and an impedance matching network on the other hand. The high voltage capacitance isolates the high DC voltage from the RF electronics, while the RF potential is passed across the high voltage capacitance to the plasma. An inductor protects at least the RF power supply, and desirably the impedance matching network as well, from a short that might occur across the high voltage capacitance. The discharge cell and the probe which holds the sample are configured and disposed to prevent the probe's components, which are maintained at ground potential, from bridging between the relatively low vacuum region in communication with the glow discharge maintained within the cell on the one hand, and the relatively high vacuum region surrounding the probe and cell on the other hand. The probe and cell also are configured and disposed to prevent the probe's components from electrically shorting the cell's components.

  20. PRODUCTION OF HIGHER STRENGTH THIN WALLED GLOW DISCHARGE POLYMER SHELLS FOR CRYOGENIC EXPERIMENTS AT OMEGA

    SciTech Connect (OSTI)

    NIKROO,A; CZECHOWICZ,DG; CASTILLO,ER; PONTELANDOLFO,JM

    2002-04-01

    OAK A271 PRODUCTION OF HIGHER STRENGTH THIN WALLED GLOW DISCHARGE POLYMER SHELLS FOR CRYOGENIC EXPERIMENTS AT OMEGA. Thin walled polymer shells are needed for OMEGA cryogenic laser experiments. These capsules need to be about 900 {micro}m in diameter and as thin as possible (approx 1-2 {micro}m), while having enough strength to be filled with DT as fast as possible to about 1000 atm. The authors have found that by optimizing the coating parameters in the glow discharge polymer (GDP) deposition system, traditionally used for making ICF targets, they can routinely make robust, {approx} 1.5 {micro}m thick, 900 {micro}m diameter GDP shells with buckle strengths of over 0.3 atm. This is twice the strength of shells made prior to the optimization and is comparable to values quoted for polyimide shells. In addition, these shells were found to be approximately three times more permeable and over 20% denser than previously made GDP shells. The combination of higher strength and permeability is ideal for direct drive cryogenic targets at OMEGA. Shells as thin as 0.5 {micro}m have been made. In this paper, the authors discuss the shell fabrication process, effects of modifying various GDP deposition parameters on shell properties and chemical composition.

  1. Radio-frequency powered glow discharge device and method with high voltage interface

    DOE Patents [OSTI]

    Duckworth, D.C.; Marcus, R.K.; Donohue, D.L.; Lewis, T.A.

    1994-06-28

    A high voltage accelerating potential, which is supplied by a high voltage direct current power supply, is applied to the electrically conducting interior wall of an RF powered glow discharge cell. The RF power supply desirably is electrically grounded, and the conductor carrying the RF power to the sample held by the probe is desirably shielded completely excepting only the conductor's terminal point of contact with the sample. The high voltage DC accelerating potential is not supplied to the sample. A high voltage capacitance is electrically connected in series between the sample on the one hand and the RF power supply and an impedance matching network on the other hand. The high voltage capacitance isolates the high DC voltage from the RF electronics, while the RF potential is passed across the high voltage capacitance to the plasma. An inductor protects at least the RF power supply, and desirably the impedance matching network as well, from a short that might occur across the high voltage capacitance. The discharge cell and the probe which holds the sample are configured and disposed to prevent the probe's components, which are maintained at ground potential, from bridging between the relatively low vacuum region in communication with the glow discharge maintained within the cell on the one hand, and the relatively high vacuum region surrounding the probe and cell on the other hand. The probe and cell also are configured and disposed to prevent the probe's components from electrically shorting the cell's components. 11 figures.

  2. Investigation of helium ion production in constricted direct current plasma ion source with layered-glows

    SciTech Connect (OSTI)

    Lee, Yuna; Chung, Kyoung-Jae; Park, Yeong-Shin; Hwang, Y. S.; Center for Advance Research in Fusion Reactor Engineering, Seoul National University, Seoul 151-744

    2014-02-15

    Generation of helium ions is experimentally investigated with a constricted direct current (DC) plasma ion source operated at layered-glow mode, in which electrons could be accelerated through multiple potential structures so as to generate helium ions including He{sup 2+} by successive ionization collisions in front of an extraction aperture. The helium discharge is sustained with the formation of a couple of stable layers and the plasma ball with high density is created near the extraction aperture at the operational pressure down to 0.6 Torr with concave cathodes. The ion beam current extracted with an extraction voltage of 5 kV is observed to be proportional to the discharge current and inversely proportional to the operating pressure, showing high current density of 130 mA/cm{sup 2} and power density of 0.52 mA/cm{sup 2}/W. He{sup 2+} ions, which were predicted to be able to exist due to multiple-layer potential structure, are not observed. Simple calculation on production of He{sup 2+} ions inside the plasma ball reveals that reduced operating pressure and increased cathode area will help to generate He{sup 2+} ions with the layered-glow DC discharge.

  3. Charging of dust grains in a nonequilibrium plasma of a stratified glow discharge

    SciTech Connect (OSTI)

    Sukhinin, G. I.; Fedoseev, A. V.

    2007-12-15

    A theoretical model is presented that describes the charging of dust grains in the positive plasma column of a stratified glow dc discharge in argon. A one-dimensional self-consistent model is used to obtain axial profiles of the electric field, as well as the electron energy distribution function along the axis of the discharge tube. Radial profiles of the electric field are determined in the ambipolar diffusion approximation. It is assumed that, in the radial direction, the electron distribution function depends only on the total electron energy. Two-dimensional distributions of the discharge plasma parameters are calculated and used to determine the potential and charge of a test dust grain at a certain point within the discharge and the electrostatic forces acting on it. It is shown that the grain charge distribution depends strongly on the nonequilibrium electron distribution function and on the nonuniform distribution of the electric field in a stratified glow discharge. A discussion is presented on the suspension of dust grains, the separation of grains by size in the discharge striations, and a possible mechanism for the onset of vortex dust motion at the edge of a dust cloud.

  4. Account of nonlocal ionization by fast electrons in the fluid models of a direct current glow discharge

    SciTech Connect (OSTI)

    Rafatov, I.; Bogdanov, E. A.; Kudryavtsev, A. A.

    2012-09-15

    We developed and tested a simple hybrid model for a glow discharge, which incorporates nonlocal ionization by fast electrons into the 'simple' and 'extended' fluid frameworks. Calculations have been performed for an argon gas. Comparison with the experimental data as well as with the hybrid (particle) and fluid modelling results demonstated good applicability of the proposed model.

  5. Observation of dust torus with poloidal rotation in direct current glow discharge plasma

    SciTech Connect (OSTI)

    Kaur, Manjit Bose, Sayak; Chattopadhyay, P. K. Sharma, Devendra; Ghosh, J.; Saxena, Y. C.

    2015-03-15

    Observation of dust cloud rotation in parallel-plate DC glow discharge plasma is reported here. The experiments are carried out at high pressures (∼130 Pa) with a metallic ring placed on the lower electrode (cathode). The dust cloud rotates poloidally in the vertical plane near the cathode surface. This structure is continuous toroidally. Absence of magnetic field rules out the possibility of E × B induced ion flow as the cause of dust rotation. The dust rotational structures exist even with water cooled cathode. Therefore, temperature gradient driven mechanisms, such as thermophoretic force, thermal creep flow, and free convection cannot be causing the observed dust rotation. Langmuir probe measurement reveals the existence of a sharp density gradient near the location of the rotating dust cloud. The gradient in the density, giving rise to a gradient in the ion drag force, has been identified as the principal cause behind the rotation of dust particles.

  6. Non-local Effects in a Stratified Glow Discharge With Dusty Particles

    SciTech Connect (OSTI)

    Sukhinin, G. I.; Fedoseev, A. V.; Ramazanov, T. S.; Amangaliyeva, R. Zh.; Dosbolayev, M. K.; Jumabekov, A. N.

    2008-09-07

    The work is aimed to describe non-local effects in the positive column of a low pressure stratified DC glow discharge in argon with dusty particles in a vertical cylindrical discharge tube. The numerical calculations of plasma parameters in the axis of the discharge tube were performed with the help of hybrid model based on the solution of non-local Boltzmann equation for EEDF. Distributions of optical emission from striations were measured experimentally. It is shown that in a stratified positive column the EEDF is not Maxwellian and even non-monotonous. Also, the effect of displacing of optical emission distribution relative to the electric field is shown both by numerical simulation and experimental measurements.

  7. Decomposition of toluene in a steady-state atmospheric-pressure glow discharge

    SciTech Connect (OSTI)

    Trushkin, A. N.; Grushin, M. E.; Kochetov, I. V.; Trushkin, N. I.; Akishev, Yu. S.

    2013-02-15

    Results are presented from experimental studies of decomposition of toluene (C{sub 6}H{sub 5}CH{sub 3}) in a polluted air flow by means of a steady-state atmospheric pressure glow discharge at different water vapor contents in the working gas. The experimental results on the degree of C{sub 6}H{sub 5}CH{sub 3} removal are compared with the results of computer simulations conducted in the framework of the developed kinetic model of plasma chemical decomposition of toluene in the N{sub 2}: O{sub 2}: H{sub 2}O gas mixture. A substantial influence of the gas flow humidity on toluene decomposition in the atmospheric pressure glow discharge is demonstrated. The main mechanisms of the influence of humidity on C{sub 6}H{sub 5}CH{sub 3} decomposition are determined. The existence of two stages in the process of toluene removal, which differ in their duration and the intensity of plasma chemical decomposition of C{sub 6}H{sub 5}CH{sub 3} is established. Based on the results of computer simulations, the composition of the products of plasma chemical reactions at the output of the reactor is analyzed as a function of the specific energy deposition and gas flow humidity. The existence of a catalytic cycle in which hydroxyl radical OH acts a catalyst and which substantially accelerates the recombination of oxygen atoms and suppression of ozone generation when the plasma-forming gas contains water vapor is established.

  8. Experimental Analysis and Numerical Simulation of Tensile Behaviour of TiNi Shape Memory Alloy Fibres Reinforced Epoxy Matrix Composite at High Temperatures

    SciTech Connect (OSTI)

    Sahli, M. L.; Necib, B.

    2011-05-04

    The shape memory alloys (SMA) possess both sensing and actuating functions due to their shape memory effect, pseudo-elasticity, high damping capability and other remarkable properties. Combining the SMA with other materials can create intelligent or smart composites. The epoxy resin composites filled with TiNi alloys fibres were fabricated and their mechanical properties have been investigated. In this study, stress/strain relationships for a composite with embedded shape memory materials (SMA) fibres are presented. The paper illustrates influence of the SMA fibres upon changes in mechanical behaviour of a composite plate with the SMA components, firstly and secondly, the actuating ability and reliability of shape memory alloy hybrid composites.

  9. Studies on gas breakdown in pulsed radio frequency atmospheric pressure glow discharges

    SciTech Connect (OSTI)

    Huo, W. G. [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116023 (China) [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116023 (China); School of Physics and Electronic Technology, Liaoning Normal University, Dalian 116029 (China); Jian, S. J.; Yao, J.; Ding, Z. F., E-mail: zfding@dlut.edu.cn [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116023 (China)

    2014-05-15

    In pulsed RF atmospheric pressure glow discharges, the gas breakdown judged by the rapid drop in the amplitude of the pulsed RF voltage is no longer universally true. The steep increment of the plasma-absorbed RF power is proposed to determine the gas breakdown. The averaged plasma-absorbed RF power over a pulse period is used to evaluate effects of the preceding pulsed RF discharge on the breakdown voltage of the following one, finding that the breakdown voltage decreases with the increment in the averaged plasma-absorbed RF power under constant pulse duty ratio. Effects of the pulse off-time on the breakdown voltage and the breakdown delay time are also studied. The obtained dependence of the breakdown voltage on the pulse off-time is indicative of the transitional plasma diffusion processes in the afterglow. The breakdown voltage varies rapidly as the plasma diffuses fast in the region of moderate pulse off-time. The contribution of nitrogen atom recombination at the alumina surface is demonstrated in the prolonged memory effect on the breakdown delay time vs. the pulse off-time and experimentally validated by introducing a trace amount of nitrogen into argon at short and long pulse off-times.

  10. ULTRAVIOLET INDUCED MOTION OF A FLUORESCENT DUST CLOUD IN AN ARGON DIRECT CURRENT GLOW DISCHARGE PLASMA

    SciTech Connect (OSTI)

    Hvasta, M.G.; and Zwicker, A.

    2008-01-01

    Dusty plasmas consist of electrons, ions, neutrals and nm-?m sized particles commonly referred to as dust. In man-made plasmas this dust may represent impurities in a tokamak or plasma etching processing. In astrophysical plasmas this dust forms structures such as planetary rings and comet tails. To study dusty plasma dynamics an experiment was designed in which a 3:1 silica (<5 ?m diameter) and fl uorescent dust mixture was added to an argon DC glow discharge plasma and exposed to UV radiation. This fl uorescent lighting technique offers an advantage over laser scattering (which only allows two-dimensional slices of the cloud to be observed) and is simpler than scanning mirror techniques or particle image velocimetry. Under typical parameters (P=150 mTorr, V anode= 100 V, Vcathode= -400 V, Itotal < 2mA) when the cloud is exposed to the UV light (100W, ? = 365 nm) the mixture fl uoresces, moves ~2mm towards the light source and begins rotating in a clockwise manner (as seen from the cathode). By calibrating a UV lamp and adjusting the relative intensity of the UV with a variable transformer it was found that both translational and rotational velocities are a function of UV intensity. Additionally, it was determined that bulk cloud rotation is not seen when the dust tray is not grounded while bulk translation is. This ongoing experiment represents a novel way to control contamination in man-made plasmas and a path to a better understanding of UV-bathed plasma systems in space..

  11. A low-power magnetic-field-assisted plasma jet generated by dielectric-barrier discharge enhanced direct-current glow discharge at atmospheric pressure

    SciTech Connect (OSTI)

    Jiang, Weiman; Tang, Jie Wang, Yishan; Zhao, Wei; Duan, Yixiang; Research Center of Analytical Instrumentation, Sichuan University, Chengdu 610064

    2014-01-06

    A magnetic field is introduced to the dielectric-barrier discharge enhanced direct-current glow discharge for efficient plasma generation, with the discharge power of 2.7?W and total energy consumption reduced to 34% of the original. By spatially examining the emission spectra and plasma temperature, it is found that their peaks shift from edges to the center and the negative and anode glows merge into the positive column and disappear, accompanied by improvement of uniformity and chemical activity of the enlarged plasma. This lies in the enhancement of ionization in the curved and lengthened electron path and the dispersion of discharge domains.

  12. Effect of hydrogen ratio on plasma parameters of N{sub 2}-H{sub 2} gas mixture glow discharge

    SciTech Connect (OSTI)

    El-Brulsy, R. A.; Abd Al-Halim, M. A.; Abu-Hashem, A.; Rashed, U. M.; Hassouba, M. A.

    2012-05-15

    A dc plane glow discharge in a nitrogen-hydrogen (N{sub 2}-H{sub 2}) gas mixture has been operated at discharge currents of 10 and 20 mA. The electron energy distribution function (EEDF) at different hydrogen concentrations is measured. A Maxwellian EEDF is found in the positive column region, while in both cathode fall and negative glow regions, a non-Maxwellian one is observed. Langmuir electric probes are used at different axial positions, gas pressures, and hydrogen concentrations to measure the electron temperature and plasma density. The electron temperature is found to increase with increasing H{sub 2} concentration and decrease with increasing both the axial distance from the cathode and the mixture pressure. At first, with increasing distance from the cathode, the ion density decreases, while the electron density increases; then, as the anode is further approached, they remain nearly constant. At different H{sub 2} concentrations, the electron and ion densities decrease with increasing the mixture pressure. Both the electron and ion densities slightly decrease with increasing H{sub 2} concentration.

  13. Crystallization process

    DOE Patents [OSTI]

    Adler, Robert J. (Shaker Heights, OH); Brown, William R. (Brecksville, OH); Auyang, Lun (Highland Heights, OH); Liu, Yin-Chang (Richmond Heights, OH); Cook, W. Jeffrey (Cleveland Heights, OH)

    1986-01-01

    An improved crystallization process is disclosed for separating a crystallizable material and an excluded material which is at least partially excluded from the solid phase of the crystallizable material obtained upon freezing a liquid phase of the materials. The solid phase is more dense than the liquid phase, and it is separated therefrom by relative movement with the formation of a packed bed of solid phase. The packed bed is continuously formed adjacent its lower end and passed from the liquid phase into a countercurrent flow of backwash liquid. The packed bed extends through the level of the backwash liquid to provide a drained bed of solid phase adjacent its upper end which is melted by a condensing vapor.

  14. Epitaxial strengthening of crystals

    DOE Patents [OSTI]

    Morris, Robert C. (Ledgewood, NJ); Marion, II, John E. (Livermore, CA); Gaultieri, Devlin M. (Ledgewood, NJ)

    1988-01-01

    An epitaxial layer is used to place the surface of a crystal in compression o as to greatly increase the durability of the crystal such as a laser medium crystal.

  15. Final Report DE-FG02-00ER54583: "Physics of Atmospheric Pressure Glow Discharges" and "Nanoparticle Nucleation and Dynamics in Low-Pressure Plasmas"

    SciTech Connect (OSTI)

    Uwe Kortshagen; Joachim Heberlein; Steven L. Girshick

    2009-06-01

    This project was funded over two periods of three years each, with an additional year of no-cost extension. Research in the first funding period focused on the physics of uniform atmospheric pressure glow discharges, the second funding period was devoted to the study of the dynamics of nanometer-sized particles in plasmas.

  16. Monochromator Crystal Glitch Library

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    SSRL's Monochromator Crystal Glitch Library allows users to view glitch spectra online, list specific crystal orientations, and download PDF files of the glitch spectra. (Specialized Interface)

  17. Mixed crystal organic scintillators

    DOE Patents [OSTI]

    Zaitseva, Natalia P; Carman, M Leslie; Glenn, Andrew M; Hamel, Sebastien; Hatarik, Robert; Payne, Stephen A; Stoeffl, Wolfgang

    2014-09-16

    A mixed organic crystal according to one embodiment includes a single mixed crystal having two compounds with different bandgap energies, the organic crystal having a physical property of exhibiting a signal response signature for neutrons from a radioactive source, wherein the signal response signature does not include a significantly-delayed luminescence characteristic of neutrons interacting with the organic crystal relative to a luminescence characteristic of gamma rays interacting with the organic crystal. According to one embodiment, an organic crystal includes bibenzyl and stilbene or a stilbene derivative, the organic crystal having a physical property of exhibiting a signal response signature for neutrons from a radioactive source.

  18. CRYSTAL COLLIMATION AT RHIC.

    SciTech Connect (OSTI)

    FLILLER,R.P.,III.DREES,A.GASSNER,D.HAMMONS,L.MCINTYRE,G.PEGGS,S.TRBOJEVIC,D.BIRYUKOV,V.CHESNOKOV,Y.TEREKHOV,V.

    2003-06-19

    Crystal Channeling occurs when an ion enters a crystal with a small angle with respect to the crystal planes. The electrostatic interaction between the incoming ion and the lattice causes the ion to follow the crystal planes. By mechanically bending a crystal, it is possible to use a crystal to deflect ions. One novel use of a bent crystal is to use it to channel beam halo particles into a collimator downstream. By deflecting the halo particles into a collimator with a crystal it may be possible to improve collimation efficiency as compared to a single collimator. A bent crystal is installed in the yellow ring of the Relativistic Heavy Ion Collider (RHIC). In this paper we discuss our experience with the crystal collimator, and compare our results to previous data, simulation, and theoretical prediction.

  19. Pressure cryocooling protein crystals

    DOE Patents [OSTI]

    Kim, Chae Un; Gruner, Sol M.

    2011-10-04

    Preparation of cryocooled protein crystal is provided by use of helium pressurizing and cryocooling to obtain cryocooled protein crystal allowing collection of high resolution data and by heavier noble gas (krypton or xenon) binding followed by helium pressurizing and cryocooling to obtain cryocooled protein crystal for collection of high resolution data and SAD phasing simultaneously. The helium pressurizing is carried out on crystal coated to prevent dehydration or on crystal grown in aqueous solution in a capillary.

  20. CRYSTAL COLLIMATION AT RHIC.

    SciTech Connect (OSTI)

    FLILLER,III, R.P.; DREES,A.; GASSNER,D.; HAMMONS,L.; MCINTYRE,G.; PEGGS,S.; TRBOJEVIC,D.; BIRYUKOV,V.; CHESNKOV,Y.; TEREKHOV,V.

    2002-06-02

    For the year 2001 run, a bent crystal was installed in the yellow ring of the Relativistic Heavy Ion Collider (RHIC). The crystal forms the first stage of a two stage collimation system. By aligning the crystal to the beam, halo particles are channeled through the crystal and deflected into a copper scraper. The purpose is to reduce beam halo with greater efficiency than with a scraper alone. In this paper we present the first results from the use of the crystal collimator. We compare the crystal performance under various conditions, such as different particle species, and beta functions.

  1. Multiple solutions in the theory of direct current glow discharges: Effect of plasma chemistry and nonlocality, different plasma-producing gases, and 3D modelling

    SciTech Connect (OSTI)

    Almeida, P. G. C.; Benilov, M. S.

    2013-10-15

    The work is aimed at advancing the multiple steady-state solutions that have been found recently in the theory of direct current (DC) glow discharges. It is shown that an account of detailed plasma chemistry and non-locality of electron transport and kinetic coefficients results in an increase of the number of multiple solutions but does not change their pattern. Multiple solutions are shown to exist for discharges in argon and helium provided that discharge pressure is high enough. This result indicates that self-organization in DC glow microdischarges can be observed not only in xenon, which has been the case until recently, but also in other plasma-producing gases; a conclusion that has been confirmed by recent experiments. Existence of secondary bifurcations can explain why patterns of spots grouped in concentric rings, observed in the experiment, possess in many cases higher number of spots in outer rings than in inner ones.

  2. Modification of Thermal Emission via Metallic Photonic Crystals

    SciTech Connect (OSTI)

    Norris, David J.; Stein, Andreas; George, Steven M.

    2012-07-30

    Photonic crystals are materials that are periodically structured on an optical length scale. It was previously demonstrated that the glow, or thermal emission, of tungsten photonic crystals that have a specific structure - known as the 'woodpile structure' - could be modified to reduce the amount of infrared radiation from the material. This ability has implications for improving the efficiency of thermal emission sources and for thermophotovoltaic devices. The study of this effect had been limited because the fabrication of metallic woodpile structures had previously required a complex fabrication process. In this project we pursued several approaches to simplify the fabrication of metallic photonic crystals that are useful for modification of thermal emission. First, we used the self-assembly of micrometer-scale spheres into colloidal crystals known as synthetic opals. These opals can then be infiltrated with a metal and the spheres removed to obtain a structure, known as an inverse opal, in which a three-dimensional array of bubbles is embedded in a film. Second, we used direct laser writing, in which the focus of an infrared laser is moved through a thin film of photoresist to form lines by multiphoton polymerization. Proper layering of such lines can lead to a scaffold with the woodpile structure, which can be coated with a refractory metal. Third, we explored a completely new approach to modified thermal emission - thin metal foils that contain a simple periodic surface pattern, as shown in Fig. 1. When such a foil is heated, surface plasmons are excited that propagate along the metal interface. If these waves strike the pattern, they can be converted into thermal emission with specific properties.

  3. Crystal Systems | Open Energy Information

    Open Energy Info (EERE)

    is located in Salem, Massachusetts. Crystal Systems produces sapphire crystals for optics and electronics, and silicon for photovoltaics. References Crystal Systems...

  4. Apparatus for mounting crystal

    DOE Patents [OSTI]

    Longeway, Paul A. (East Windsor, NJ)

    1985-01-01

    A thickness monitor useful in deposition or etching reactor systems comprising a crystal-controlled oscillator in which the crystal is deposited or etched to change the frequency of the oscillator. The crystal rests within a thermally conductive metallic housing and arranged to be temperature controlled. Electrode contacts are made to the surface primarily by gravity force such that the crystal is substantially free of stress otherwise induced by high temperature.

  5. Digging Crystal Deep

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

    Digging Crystal Deep 1663 Los Alamos science and technology magazine Latest Issue:October 2015 past issues All Issues » submit Digging Crystal Deep Los Alamos reengineers the insensitive high explosive responsible for keeping the B61 nuclear weapon safe against accidental detonation at the nanoscale-crystal level. October 25, 2015 Digging Crystal Deep The B61 aircraft-launched nuclear weapon New computer simulations make detailed predictions about how the explosive will behave and when it must

  6. Growing Giant Crystals

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

    Growing Giant Crystals A new process similar to making rock candy was developed at NIF to rapidly grow very large crystals that are about 2 cubic feet in size and weigh up to 800 pounds-about the weight of a large grizzly bear! The crystals are made of potassium dihydrogen phosphate (or KDP), a naturally occurring chemical. In crystal form, KDP has good optical properties. Crystal plates have special optical properties, like prisms, that transmit, bend, and break light up into the spectrum of

  7. Photonic crystal light source

    DOE Patents [OSTI]

    Fleming, James G. (Albuquerque, NM); Lin, Shawn-Yu (Albuquerque, NM); Bur, James A. (Corrales, NM)

    2004-07-27

    A light source is provided by a photonic crystal having an enhanced photonic density-of-states over a band of frequencies and wherein at least one of the dielectric materials of the photonic crystal has a complex dielectric constant, thereby producing enhanced light emission at the band of frequencies when the photonic crystal is heated. The dielectric material can be a metal, such as tungsten. The spectral properties of the light source can be easily tuned by modification of the photonic crystal structure and materials. The photonic crystal light source can be heated electrically or other heating means. The light source can further include additional photonic crystals that exhibit enhanced light emission at a different band of frequencies to provide for color mixing. The photonic crystal light source may have applications in optical telecommunications, information displays, energy conversion, sensors, and other optical applications.

  8. Automated macromolecular crystallization screening

    DOE Patents [OSTI]

    Segelke, Brent W.; Rupp, Bernhard; Krupka, Heike I.

    2005-03-01

    An automated macromolecular crystallization screening system wherein a multiplicity of reagent mixes are produced. A multiplicity of analysis plates is produced utilizing the reagent mixes combined with a sample. The analysis plates are incubated to promote growth of crystals. Images of the crystals are made. The images are analyzed with regard to suitability of the crystals for analysis by x-ray crystallography. A design of reagent mixes is produced based upon the expected suitability of the crystals for analysis by x-ray crystallography. A second multiplicity of mixes of the reagent components is produced utilizing the design and a second multiplicity of reagent mixes is used for a second round of automated macromolecular crystallization screening. In one embodiment the multiplicity of reagent mixes are produced by a random selection of reagent components.

  9. Tunable plasmonic crystal

    DOE Patents [OSTI]

    Dyer, Gregory Conrad; Shaner, Eric A.; Reno, John L.; Aizin, Gregory

    2015-08-11

    A tunable plasmonic crystal comprises several periods in a two-dimensional electron or hole gas plasmonic medium that is both extremely subwavelength (.about..lamda./100) and tunable through the application of voltages to metal electrodes. Tuning of the plasmonic crystal band edges can be realized in materials such as semiconductors and graphene to actively control the plasmonic crystal dispersion in the terahertz and infrared spectral regions. The tunable plasmonic crystal provides a useful degree of freedom for applications in slow light devices, voltage-tunable waveguides, filters, ultra-sensitive direct and heterodyne THz detectors, and THz oscillators.

  10. Liquid Crystal Optofluidics

    SciTech Connect (OSTI)

    Vasdekis, Andreas E.; Cuennet, J. G.; Psaltis, D.

    2012-10-11

    By employing anisotropic fluids and namely liquid crystals, fluid flow becomes an additional degree of freedom in designing optofluidic devices. In this paper, we demonstrate optofluidic liquid crystal devices based on the direct flow of nematic liquid crystals in microfluidic channels. Contrary to previous reports, in the present embodiment we employ the effective phase delay acquired by light travelling through flowing liquid crystal, without analysing the polarisation state of the transmitted light. With this method, we demonstrate the variation in the diffraction pattern of an array of microfluidic channels acting as a grating. We also discuss our recent activities in integrating mechanical oscillators for on-chip peristaltic pumping.

  11. Phononic crystal devices

    DOE Patents [OSTI]

    El-Kady, Ihab F. (Albuquerque, NM); Olsson, Roy H. (Albuquerque, NM)

    2012-01-10

    Phononic crystals that have the ability to modify and control the thermal black body phonon distribution and the phonon component of heat transport in a solid. In particular, the thermal conductivity and heat capacity can be modified by altering the phonon density of states in a phononic crystal. The present invention is directed to phononic crystal devices and materials such as radio frequency (RF) tags powered from ambient heat, dielectrics with extremely low thermal conductivity, thermoelectric materials with a higher ratio of electrical-to-thermal conductivity, materials with phononically engineered heat capacity, phononic crystal waveguides that enable accelerated cooling, and a variety of low temperature application devices.

  12. Glow-to-arc transition events in H{sub 2}-Ar direct current pulsed plasma: Automated measurement of current and voltage

    SciTech Connect (OSTI)

    Mendes, Luciano A.; Rodrigues, Jhonatam C.; Mafra, Marcio

    2012-01-15

    The glow-to-arc transition phenomena (arcing) observed in plasma reactors used in materials processing was studied through the arcs characteristic current and voltage waveforms. In order to capture these arcs signals, a LABVIEW based automated instrumentation system (ARCVIEW) was developed, including the integration of an oscilloscope equipped with proper current and voltage probes. The system also allows capturing the process parameters at the arc occurrence moments, which were used to map the arcs events conditions. Experiments in H{sub 2}-Ar DC pulsed plasma returned signals data from 215 arcs events, which were analyzed through software routines. According to the results, an anti-arcing system should react in the time order of few microseconds to prevent most of the damage caused by the undesired arcing phenomena.

  13. SU-E-T-354: Peak Temperature Ratio of TLD Glow Curves to Investigate the Spatial Dependence of LET in a Clinical Proton Beam

    SciTech Connect (OSTI)

    Reft, C [UniversityChicago, Chicago, IL (United States); Pankuch, M; Ramirez, H [ProCure Treatment Centers, Warrenville, IL (United States)

    2014-06-01

    Purpose: Use the ratio of the two high temperature peaks (HTR) in TLD 700 glow curves to investigate spatial dependence of the linear energy transfer (LET) in proton beams. Studies show that the relative biological effectiveness (RBE) depends upon the physical dose as well as its spatial distribution. Although proton therapy uses a spatially invariant RBE of 1.1, studies suggest that the RBE increases in the distal edge of a spread out Bragg peak (SOBP) due to the increased LET. Methods: Glow curve studies in TLD 700 show that the 280 C temperature peak is more sensitive to LET radiation than the 210 C temperature peak. Therefore, the areas under the individual temperature peaks for TLDs irradiated in a proton beam normalized to the peak ratio for 6 MV photons are used to determine the HTR to obtain information on its LET. TLD 700 chips with dimensions 0.310.310.038 cc are irradiated with 90 MeV protons at varying depths in a specially designed blue wax phantom to investigate LET spatial dependence. Results: Five TLDs were placed at five different depths of the percent depth dose curve (PDD) of range 16.2 cm: center of the SOPB and approximately at the 99% distal edge, 90%, 75% and 25% of the PDD, respectively. HTR was 1.3 at the center of the SOBP and varied from 2.2 to 3.9 which can be related to an LET variation from 0.5 to 18 KeV/? via calibration with radiation beams of varying LET. Conclusion: HTR data show a spatially invariant LET slightly greater than the 6 MV radiations in the SOBP, but a rapidly increasing LET at the end of the proton range. These results indicate a spatial variation in RBE with potential treatment consequences when selecting treatment margins to minimize the uncertainties in proton RBE.

  14. Frequency doubling crystals

    DOE Patents [OSTI]

    Wang, Francis (Danville, CA); Velsko, Stephan P. (Livermore, CA)

    1989-01-01

    A systematic approach to the production of frequency conversion crystals is described in which a chiral molecule has attached to it a "harmonic generating unit" which contributes to the noncentrosymmetry of the molecule. Certain preferred embodiments of such harmonic generating units include carboxylate, guanadyly and imidazolyl units. Certain preferred crystals include L-arginine fluoride, deuterated L-arginine fluoride, L-arginine chloride monohydrate, L-arginine acetate, dithallium tartrate, ammonium N-acetyl valine, N-acetyl tyrosine and N-acetyl hydroxyproline. Chemical modifications of the chiral molecule, such as deuteration, halogenation and controlled counterion substitution are available to adapt the dispersive properties of a crystal in a particular wavelength region.

  15. FRACTIONAL CRYSTALLIZATION FEED ENVELOPE

    SciTech Connect (OSTI)

    HERTING DL

    2008-03-19

    Laboratory work was completed on a set of evaporation tests designed to establish a feed envelope for the fractional crystallization process. The feed envelope defines chemical concentration limits within which the process can be operated successfully. All 38 runs in the half-factorial design matrix were completed successfully, based on the qualitative definition of success. There is no feed composition likely to be derived from saltcake dissolution that would cause the fractional crystallization process to not meet acceptable performance requirements. However, some compositions clearly would provide more successful operation than other compositions.

  16. Direct flow crystal growth system

    DOE Patents [OSTI]

    Montgomery, Kenneth E. (Tracy, CA); Milanovich, Fred P. (Lafayette, CA)

    1992-01-01

    A crystal is grown in a constantly filtered solution which is flowed directly into the growing face of a crystal. In a continuous flow system, solution at its saturation temperature is removed from a crystal growth tank, heated above its saturation temperature, filtered, cooled back to its saturation temperature, and returned to the tank.

  17. Silicon crystal growing by oscillating crucible technique

    DOE Patents [OSTI]

    Schwuttke, G.H.; Kim, K.M.; Smetana, P.

    1983-08-03

    A process for growing silicon crystals from a molten melt comprising oscillating the container during crystal growth is disclosed.

  18. Plenum type crystal growth process

    DOE Patents [OSTI]

    Montgomery, Kenneth E. (Tracy, CA)

    1992-01-01

    Crystals are grown in a tank which is divided by a baffle into a crystal growth region above the baffle and a plenum region below the baffle. A turbine blade or stirring wheel is positioned in a turbine tube which extends through the baffle to generate a flow of solution from the crystal growing region to the plenum region. The solution is pressurized as it flows into the plenum region. The pressurized solution flows back to the crystal growing region through return flow tubes extending through the baffle. Growing crystals are positioned near the ends of the return flow tubes to receive a direct flow of solution.

  19. BY SILICON CRYSTALS

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

    c October 29, 1942 a 1 1 _MIGH aECTgFXCATIOH - BY SILICON CRYSTALS . . c .. I n. The excellent pesformmce of Brftieh "red dot" c r y s t a l s f e explained R R due t o the kgife edge contact i n a t A polfehod ~ X ' f l i C B o H i g h frequency m c t l f f c n t f o n 8ependre c r i t i c a l l y on the ape%e;y of the rectifytnc boundary layer o f the crystal, C, For hl#$ comvere~on e f f i c i e n c y , the product c d t h i ~ capacity m a o f ' t h e @forward" (bulk) re-.

  20. Crystal face temperature determination means

    DOE Patents [OSTI]

    Nason, D.O.; Burger, A.

    1994-11-22

    An optically transparent furnace having a detection apparatus with a pedestal enclosed in an evacuated ampule for growing a crystal thereon is disclosed. Temperature differential is provided by a source heater, a base heater and a cold finger such that material migrates from a polycrystalline source material to grow the crystal. A quartz halogen lamp projects a collimated beam onto the crystal and a reflected beam is analyzed by a double monochromator and photomultiplier detection spectrometer and the detected peak position in the reflected energy spectrum of the reflected beam is interpreted to determine surface temperature of the crystal. 3 figs.

  1. Optics of globular photonic crystals

    SciTech Connect (OSTI)

    Gorelik, V S

    2007-05-31

    The results of experimental and theoretical studies of the optical properties of globular photonic crystals - new physical objects having a crystal structure with the lattice period exceeding considerably the atomic size, are presented. As globular photonic crystals, artificial opal matrices consisting of close-packed silica globules of diameter {approx}200 nm were used. The reflection spectra of these objects characterising the parameters of photonic bands existing in these crystals in the visible spectral region are presented. The idealised models of the energy band structure of photonic crystals investigated in the review give analytic dispersion dependences for the group velocity and the effective photon mass in a globular photonic crystal. The characteristics of secondary emission excited in globular photonic crystals by monochromatic and broadband radiation are presented. The results of investigations of single-photon-excited delayed scattering of light observed in globular photonic crystals exposed to cw UV radiation and radiation from a repetitively pulsed copper vapour laser are presented. The possibilities of using globular photonic crystals as active media for lasing in different spectral regions are considered. It is proposed to use globular photonic crystals as sensitive sensors in optoelectronic devices for molecular analysis of organic and inorganic materials by the modern methods of laser spectroscopy. The results of experimental studies of spontaneous and stimulated globular scattering of light are discussed. The conditions for observing resonance and two-photon-excited delayed scattering of light are found. The possibility of accumulation and localisation of the laser radiation energy inside a globular photonic crystal is reported. (review)

  2. Lamella settler crystallizer

    DOE Patents [OSTI]

    Maimoni, Arturo (Orinda, CA)

    1990-01-01

    A crystallizer which incorporates a lamella settler and which is particularly applicable for use in batteries and power cells for electric vehicles or stationary applications. The lamella settler can be utilized for coarse particle separation or for agglomeration, and is particularly applicable to aluminum-air batteries or power cells for solving the hydrargillite (aluminum-hydroxide) removal problems from such batteries. This invention provides the advantages of very low energy consumption, turbulence, shear, cost and maintenance. Thus, due to the low shear and low turbulence of this invention, it is particularly effective in the control of aluminum hydroxide particle size distribution in the various sections of an aluminum-air system, as well as in other electrochemical systems requiring separation for phases of different densities.

  3. Lamella settler crystallizer

    DOE Patents [OSTI]

    Maimoni, A.

    1990-12-18

    A crystallizer is described which incorporates a lamella settler and which is particularly applicable for use in batteries and power cells for electric vehicles or stationary applications. The lamella settler can be utilized for coarse particle separation or for agglomeration, and is particularly applicable to aluminum-air batteries or power cells for solving the hydrargillite (aluminum-hydroxide) removal problems from such batteries. This invention provides the advantages of very low energy consumption, turbulence, shear, cost and maintenance. Thus, due to the low shear and low turbulence of this invention, it is particularly effective in the control of aluminum hydroxide particle size distribution in the various sections of an aluminum-air system, as well as in other electrochemical systems requiring separation for phases of different densities. 3 figs.

  4. Frequency mixing crystal

    DOE Patents [OSTI]

    Ebbers, Christopher A.; Davis, Laura E.; Webb, Mark

    1992-01-01

    In a laser system for converting infrared laser light waves to visible light comprising a source of infrared laser light waves and means of harmoic generation associated therewith for production of light waves at integral multiples of the frequency of the original wave, the improvement of said means of harmonic generation comprising a crystal having the chemical formula X.sub.2 Y(NO.sub.3).sub.5 .multidot.2 nZ.sub.2 o wherein X is selected from the group consisting of Li, Na, K, Rb, Cs, and Tl; Y is selected from the group consisting of Sc, Y, La, Ce, Nd, Pr, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Al, Ga, and In; Z is selected from the group consisting of H and D; and n ranges from 0 to 4.

  5. Watching a Liquid-Crystal Helix Unwind

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

    science. Introducing molecular chirality into a liquid crystal may lead to a twisting force that can modify the equilibrium state usually observed in liquid crystals, resulting...

  6. Membrane Protein Crystallization in Lipidic Mesophases. Hosting...

    Office of Scientific and Technical Information (OSTI)

    Membrane Protein Crystallization in Lipidic Mesophases. Hosting Lipid Effects on the ... Citation Details In-Document Search Title: Membrane Protein Crystallization in Lipidic ...

  7. Multicolor photonic crystal laser array

    DOE Patents [OSTI]

    Wright, Jeremy B; Brener, Igal; Subramania, Ganapathi S; Wang, George T; Li, Qiming

    2015-04-28

    A multicolor photonic crystal laser array comprises pixels of monolithically grown gain sections each with a different emission center wavelength. As an example, two-dimensional surface-emitting photonic crystal lasers comprising broad gain-bandwidth III-nitride multiple quantum well axial heterostructures were fabricated using a novel top-down nanowire fabrication method. Single-mode lasing was obtained in the blue-violet spectral region with 60 nm of tuning (or 16% of the nominal center wavelength) that was determined purely by the photonic crystal geometry. This approach can be extended to cover the entire visible spectrum.

  8. Crystal growth and annealing method and apparatus

    DOE Patents [OSTI]

    Gianoulakis, Steven E.; Sparrow, Robert

    2001-01-01

    A method and apparatus for producing crystals that minimizes birefringence even at large crystal sizes, and is suitable for production of CaF.sub.2 crystals. The method of the present invention comprises annealing a crystal by maintaining a minimal temperature gradient in the crystal while slowly reducing the bulk temperature of the crystal. An apparatus according to the present invention includes a thermal control system added to a crystal growth and annealing apparatus, wherein the thermal control system allows a temperature gradient during crystal growth but minimizes the temperature gradient during crystal annealing. An embodiment of the present invention comprises a secondary heater incorporated into a conventional crystal growth and annealing apparatus. The secondary heater supplies heat to minimize the temperature gradients in the crystal during the annealing process. The secondary heater can mount near the bottom of the crucible to effectively maintain appropriate temperature gradients.

  9. Crystal face temperature determination means

    DOE Patents [OSTI]

    Nason, Donald O. (Goleta, CA); Burger, Arnold (Nashville, TN)

    1994-01-01

    An optically transparent furnace (10) having a detection apparatus (29) with a pedestal (12) enclosed in an evacuated ampule (16) for growing a crystal (14) thereon. Temperature differential is provided by a source heater (20), a base heater (24) and a cold finger (26) such that material migrates from a polycrystalline source material (18) to grow the crystal (14). A quartz halogen lamp (32) projects a collimated beam (30) onto the crystal (14) and a reflected beam (34) is analyzed by a double monochromator and photomultiplier detection spectrometer (40) and the detected peak position (48) in the reflected energy spectrum (44) of the reflected beam (34) is interpreted to determine surface temperature of the crystal (14).

  10. PREPARATION OF REFRACTORY OXIDE CRYSTALS

    DOE Patents [OSTI]

    Grimes, W.R.; Shaffer, J.H.; Watson, G.M.

    1962-11-13

    A method is given for preparing uranium dioxide, thorium oxide, and beryllium oxide in the form of enlarged individual crystals. The surface of a fused alkali metal halide melt containing dissolved uranium, thorium, or beryllium values is contacted with a water-vapor-bearing inert gas stream at a rate of 5 to 10 cubic centimeters per minute per square centimeter of melt surface area. Growth of individual crystals is obtained by prolonged contact. Beryllium oxide-coated uranium dioxide crystals are prepared by disposing uranium dioxide crystals 5 to 20 microns in diameter in a beryllium-containing melt and contacting the melt with a water-vapor-bearing inert gas stream in the same manner. (AEC)

  11. Highly Oriented Crystals in Polythiophenes

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

    Highly Oriented Crystals in Polythiophenes Conjugated polymers are being developed as the active semiconductor in devices such as light-emitting diodes, photovoltaic cells, and thin-film transistors (TFTs) for large-area and low-cost electronics. Vacuum deposited amorphous silicon is currently used in the TFTs that drive the active matrix liquid crystal displays (AM-LCDs) on laptops, computer monitors and televisions. TFTs are also used in disposable electronics such as radiofrequency

  12. Adaptive Liquid Crystal Windows

    SciTech Connect (OSTI)

    Taheri, Bahman; Bodnar, Volodymyr

    2011-12-31

    Energy consumption by private and commercial sectors in the U.S. has steadily grown over the last decade. The uncertainty in future availability of imported oil, on which the energy consumption relies strongly, resulted in a dramatic increase in the cost of energy. About 20% of this consumption are used to heat and cool houses and commercial buildings. To reduce dependence on the foreign oil and cut down emission of greenhouse gases, it is necessary to eliminate losses and reduce total energy consumption by buildings. To achieve this goal it is necessary to redefine the role of the conventional windows. At a minimum, windows should stop being a source for energy loss. Ideally, windows should become a source of energy, providing net gain to reduce energy used to heat and cool homes. It is possible to have a net energy gain from a window if its light transmission can be dynamically altered, ideally electronically without the need of operator assistance, providing optimal control of the solar gain that varies with season and climate in the U.S. In addition, the window must not require power from the building for operation. Resolution of this problem is a societal challenge and of national interest and will have a broad global impact. For this purpose, the year-round, allclimate window solution to provide an electronically variable solar heat gain coefficient (SHGC) with a wide dynamic range is needed. AlphaMicron, Inc. (AMI) developed and manufactured 1ft 1ft prototype panels for the worlds first auto-adjusting Adaptive Liquid Crystal Windows (ALCWs) that can operate from sunlight without the need for external power source and demonstrate an electronically adjustable SHGC. This novel windows are based on AlphaMicrons patented e-Tint technology, a guesthost liquid crystal system implemented on flexible, optically clear plastic films. This technology is suitable both for OEM and aftermarket (retro-fitting) lamination to new and existing windows. Low level of power consumption by ALCWs allows for on-board power electronics for automatic matching of transmission through windows to varying climate conditions without drawing the power from the power grid. ALCWs are capable of transmitting more sunlight in winters to assist in heating and less sunlight in summers to minimize overheating. As such, they can change the window from being a source of energy loss to a source of energy gain. In addition, the scalable AMIs roll-to-roll process, proved by making 1ft 1ftALCW prototype panels, allows for cost-effective production of large-scale window panels along with capability to change easily their color and shape. In addition to architectural glazing in houses and commercial buildings, ALCWs can be used in other applications where control of sunlight is needed, such as green houses, used by commercial produce growers and botanical gardens, cars, aircrafts, etc.

  13. Minimizing radiation damage in nonlinear optical crystals

    DOE Patents [OSTI]

    Cooke, D.W.; Bennett, B.L.; Cockroft, N.J.

    1998-09-08

    Methods are disclosed for minimizing laser induced damage to nonlinear crystals, such as KTP crystals, involving various means for electrically grounding the crystals in order to diffuse electrical discharges within the crystals caused by the incident laser beam. In certain embodiments, electrically conductive material is deposited onto or into surfaces of the nonlinear crystals and the electrically conductive surfaces are connected to an electrical ground. To minimize electrical discharges on crystal surfaces that are not covered by the grounded electrically conductive material, a vacuum may be created around the nonlinear crystal. 5 figs.

  14. Minimizing radiation damage in nonlinear optical crystals

    DOE Patents [OSTI]

    Cooke, D. Wayne (Santa Fe, NM); Bennett, Bryan L. (Los Alamos, NM); Cockroft, Nigel J. (Santa Fe, NM)

    1998-01-01

    Methods are disclosed for minimizing laser induced damage to nonlinear crystals, such as KTP crystals, involving various means for electrically grounding the crystals in order to diffuse electrical discharges within the crystals caused by the incident laser beam. In certain embodiments, electrically conductive material is deposited onto or into surfaces of the nonlinear crystals and the electrically conductive surfaces are connected to an electrical ground. To minimize electrical discharges on crystal surfaces that are not covered by the grounded electrically conductive material, a vacuum may be created around the nonlinear crystal.

  15. Watching a Liquid-Crystal Helix Unwind

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

    Watching a Liquid-Crystal Helix Unwind Print Liquid crystals have many versatile applications but are best known for the liquid-crystal displays that drive the billion-dollar smartphone and flat-screen industries. Chirality, the absence of inversion symmetry, plays an important role in chemistry, biology, and materials science. Introducing molecular chirality into a liquid crystal may lead to a twisting force that can modify the equilibrium state usually observed in liquid crystals, resulting in

  16. Watching a Liquid-Crystal Helix Unwind

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

    Watching a Liquid-Crystal Helix Unwind Print Liquid crystals have many versatile applications but are best known for the liquid-crystal displays that drive the billion-dollar smartphone and flat-screen industries. Chirality, the absence of inversion symmetry, plays an important role in chemistry, biology, and materials science. Introducing molecular chirality into a liquid crystal may lead to a twisting force that can modify the equilibrium state usually observed in liquid crystals, resulting in

  17. Watching a Liquid-Crystal Helix Unwind

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

    Watching a Liquid-Crystal Helix Unwind Watching a Liquid-Crystal Helix Unwind Print Wednesday, 09 December 2015 00:00 Liquid crystals have many versatile applications but are best known for the liquid-crystal displays that drive the billion-dollar smartphone and flat-screen industries. Chirality, the absence of inversion symmetry, plays an important role in chemistry, biology, and materials science. Introducing molecular chirality into a liquid crystal may lead to a twisting force that can

  18. Watching a Liquid-Crystal Helix Unwind

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

    Watching a Liquid-Crystal Helix Unwind Print Liquid crystals have many versatile applications but are best known for the liquid-crystal displays that drive the billion-dollar smartphone and flat-screen industries. Chirality, the absence of inversion symmetry, plays an important role in chemistry, biology, and materials science. Introducing molecular chirality into a liquid crystal may lead to a twisting force that can modify the equilibrium state usually observed in liquid crystals, resulting in

  19. Watching a Liquid-Crystal Helix Unwind

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

    Watching a Liquid-Crystal Helix Unwind Print Liquid crystals have many versatile applications but are best known for the liquid-crystal displays that drive the billion-dollar smartphone and flat-screen industries. Chirality, the absence of inversion symmetry, plays an important role in chemistry, biology, and materials science. Introducing molecular chirality into a liquid crystal may lead to a twisting force that can modify the equilibrium state usually observed in liquid crystals, resulting in

  20. Watching a Liquid-Crystal Helix Unwind

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

    Watching a Liquid-Crystal Helix Unwind Print Liquid crystals have many versatile applications but are best known for the liquid-crystal displays that drive the billion-dollar smartphone and flat-screen industries. Chirality, the absence of inversion symmetry, plays an important role in chemistry, biology, and materials science. Introducing molecular chirality into a liquid crystal may lead to a twisting force that can modify the equilibrium state usually observed in liquid crystals, resulting in

  1. Manufacturing method of photonic crystal

    DOE Patents [OSTI]

    Park, In Sung; Lee, Tae Ho; Ahn, Jin Ho; Biswas, Rana; Constant, Kristen P.; Ho, Kai-Ming; Lee, Jae-Hwang

    2013-01-29

    A manufacturing method of a photonic crystal is provided. In the method, a high-refractive-index material is conformally deposited on an exposed portion of a periodic template composed of a low-refractive-index material by an atomic layer deposition process so that a difference in refractive indices or dielectric constants between the template and adjacent air becomes greater, which makes it possible to form a three-dimensional photonic crystal having a superior photonic bandgap. Herein, the three-dimensional structure may be prepared by a layer-by-layer method.

  2. Calibrating Curved Crystals Used for Plasma Spectroscopy

    SciTech Connect (OSTI)

    Haugh, M. J., Jacoby, K. D., Ross, P. W., Rochau, G. Wu, M., Regan, S. P., Barrios, M. A.

    2012-10-29

    The throughput and resolving power of an X-ray spectrometer that uses a curved crystal as the diffraction element is determined primarily by the crystal X-ray reflectivity properties. This poster presents a measurement technique for these crystal parameters using a simple diode source to produce a narrow spectral band. The results from measurements on concave elliptical polyethylene terephthalate (PET) crystals and convex potassium acid phthalate (KAP) crystals show large variations in the key parameters compared to those from the flat crystal.

  3. Precision Crystal Calorimeters in High Energy Physics

    ScienceCinema (OSTI)

    Ren-Yuan Zhu

    2010-01-08

    Precision crystal calorimeters traditionally play an important role in high energy physics experiments. In the last two decades, it faces a challenge to maintain its precision in a hostile radiation environment. This paper reviews the performance of crystal calorimeters constructed for high energy physics experiments and the progress achieved in understanding crystal?s radiation damage as well as in developing high quality scintillating crystals for particle physics. Potential applications of new generation scintillating crystals of high density and high light yield, such as LSO and LYSO, in particle physics experiments is also discussed.

  4. Photonic crystal surface-emitting lasers

    DOE Patents [OSTI]

    Chua, Song Liang; Lu, Ling; Soljacic, Marin

    2015-06-23

    A photonic-crystal surface-emitting laser (PCSEL) includes a gain medium electromagnetically coupled to a photonic crystal whose energy band structure exhibits a Dirac cone of linear dispersion at the center of the photonic crystal's Brillouin zone. This Dirac cone's vertex is called a Dirac point; because it is at the Brillouin zone center, it is called an accidental Dirac point. Tuning the photonic crystal's band structure (e.g., by changing the photonic crystal's dimensions or refractive index) to exhibit an accidental Dirac point increases the photonic crystal's mode spacing by orders of magnitudes and reduces or eliminates the photonic crystal's distributed in-plane feedback. Thus, the photonic crystal can act as a resonator that supports single-mode output from the PCSEL over a larger area than is possible with conventional PCSELs, which have quadratic band edge dispersion. Because output power generally scales with output area, this increase in output area results in higher possible output powers.

  5. ARM - Field Campaign - CRYSTAL-FACE

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

    govCampaignsCRYSTAL-FACE Campaign Links CRYSTAL-FACE Website ARM Data Discovery Browse Data Comments? We would love to hear from you Send us a note below or call us at...

  6. Crystal of GTP Cyclohydrolase Type IB

    DOE Patents [OSTI]

    Swairjo, Manal A.; Iwata-Reuyl, Dirk; de Crecy-Lagard, Valerie

    2012-12-11

    This invention relates to a novel, bacterial GTP Cyclohydrolase Type IB enzyme, and the crystal structure thereof.

  7. Ames Lab 101: Growing Crystals in Space

    SciTech Connect (OSTI)

    Trivedi, Rohit

    2011-01-01

    Rohit Trivedi, distinguished professor of materials science and engineering, discusses his research with NASA to grow crystals in space.

  8. Ames Lab 101: Growing Crystals in Space

    ScienceCinema (OSTI)

    Trivedi, Rohit

    2012-08-29

    Rohit Trivedi, distinguished professor of materials science and engineering, discusses his research with NASA to grow crystals in space.

  9. Robotic CCD microscope for enhanced crystal recognition

    DOE Patents [OSTI]

    Segelke, Brent W. (San Ramon, CA); Toppani, Dominique (Livermore, CA)

    2007-11-06

    A robotic CCD microscope and procedures to automate crystal recognition. The robotic CCD microscope and procedures enables more accurate crystal recognition, leading to fewer false negative and fewer false positives, and enable detection of smaller crystals compared to other methods available today.

  10. Crystal McDonald | Department of Energy

    Office of Environmental Management (EM)

    Crystal McDonald About Us Crystal McDonald - Project Officer, Department of Energy. Crystal McDonald is a Project Officer at the Department of Energy. Most Recent A Former "Most Wanted" Building Gets a Reprieve March 16

  11. NEW RESULTS FROM CRYSTAL COLLIMATION AT RHIC.

    SciTech Connect (OSTI)

    FLILLER,R.P.,IIIDREES,A.GASSNER,D.HAMMONS,L.MCINTYRE,G.PEGGS,S.TRBOJEVIC,D.BIRYUKOV,V.CHESNOKOV,Y.TEREKHOV,V.

    2003-05-12

    In this paper, we discuss new results from the use of the crystal collimator from the 2003 run. The yellow ring of the Relativistic Heavy Ion Collider (RHIC) has a bent crystal collimator. By properly aligning the crystal to the beam halo, particles entering the crystal are deflected away from the beam and intercepted downstream in a copper scraper. The purpose of a bent crystal is to improve the collimation efficiency as compared to a scraper alone. We compare these results to previous data, simulation, and theoretical predictions.

  12. Crystal structure refinement with SHELXL

    SciTech Connect (OSTI)

    Sheldrick, George M., E-mail: gsheldr@shelx.uni-ac.gwdg.de [Department of Structural Chemistry, Georg-August Universitt Gttingen, Tammannstrae 4, Gttingen 37077 (Germany)

    2015-01-01

    New features added to the refinement program SHELXL since 2008 are described and explained. The improvements in the crystal structure refinement program SHELXL have been closely coupled with the development and increasing importance of the CIF (Crystallographic Information Framework) format for validating and archiving crystal structures. An important simplification is that now only one file in CIF format (for convenience, referred to simply as a CIF) containing embedded reflection data and SHELXL instructions is needed for a complete structure archive; the program SHREDCIF can be used to extract the .hkl and .ins files required for further refinement with SHELXL. Recent developments in SHELXL facilitate refinement against neutron diffraction data, the treatment of H atoms, the determination of absolute structure, the input of partial structure factors and the refinement of twinned and disordered structures. SHELXL is available free to academics for the Windows, Linux and Mac OS X operating systems, and is particularly suitable for multiple-core processors.

  13. Bent core liquid crystal elastomers

    SciTech Connect (OSTI)

    Verduzco, R.; DiMasi, E.; Luchette, P.; Ho Hong, S.; Harden, J.; Palffy-Muhoray, P.; Kilbey II, S.M.; Sprunt, S.; Gleeson, G.T. Jakli, A.

    2010-07-28

    Liquid crystal (LC) elastomers with bent-core side-groups incorporate the properties of bent-core liquid crystals in a flexible and self-supporting polymer network. Bent-core liquid crystal elastomers (BCEs) with uniform alignment were prepared by attaching a reactive bent-core LC to poly(hydrogenmethylsiloxane) and crosslinking with a divinyl crosslinker. Phase behavior studies indicate a nematic phase over a wide temperature range that approaches room temperature, and thermoelastic measurements show that these BCEs can reversibly change their length by more than a factor of two upon heating and cooling. Small-angle X-ray scattering studies reveal multiple, broad low-angle peaks consistent with short-range smectic C order of the bent-core side groups. A comparison of these patterns with predictions of a Landau model for short-range smectic C order shows that the length scale for smectic ordering in BCEs is similar to that seen in pure bent-core LCs. The combination of rubber elasticity and smectic ordering of the bent-core side groups suggests that BCEs may be promising materials for sensing, actuating, and other advanced applications.

  14. Asymmetrically cut crystals for synchrotron radiation monochromators

    SciTech Connect (OSTI)

    Sanchez del Rio, M. ); Cerrina, F. )

    1992-01-01

    Asymmetrically cut crystals are interesting for use in synchrotron radiation monochromators because of their good energy resolution characteristics and their focusing properties. Ray tracing codes, such as SHADOW, are very efficient in the design and development of new optical devices. In order to determine the convenience of using asymmetrically cut crystals for x-ray monochromators, SHADOW has been extended to include these kinds of crystals. The physical approach to ray tracing asymmetrically cut crystals is based on the coexistence of two periodic structures. One of these is the bulk periodic structure of the Bragg planes. Such a structure determines the existence of a rocking curve near the Bragg condition, and is implemented in SHADOW following the Darwin--Prins formalism of the dynamical theory of diffraction. The second periodic structure is a one-dimensional grating on the crystal surface, formed by the truncation of the lattice planes with the surface. This grating is responsible for the focusing properties of these crystals and plays an essential role in determining the trajectory of the rays. The combination of an asymmetric crystal and a nonplanar surface can be easily achieved by bending (Johann case) to provide improved properties. More complex cases such as the ground-bent crystals (i.e., Johansson geometry) can be considered as a particular case of asymmetrical crystals in which the angle between the Bragg planes and the surface change along the crystal surface. All these cases have been implemented in SHADOW.

  15. Phonon manipulation with phononic crystals.

    SciTech Connect (OSTI)

    Kim Bongsang; Hopkins, Patrick Edward; Leseman, Zayd C.; Goettler, Drew F.; Su, Mehmet F.; El-Kady, Ihab Fathy; Reinke, Charles M.; Olsson, Roy H., III

    2012-01-01

    In this work, we demonstrated engineered modification of propagation of thermal phonons, i.e. at THz frequencies, using phononic crystals. This work combined theoretical work at Sandia National Laboratories, the University of New Mexico, the University of Colorado Boulder, and Carnegie Mellon University; the MESA fabrication facilities at Sandia; and the microfabrication facilities at UNM to produce world-leading control of phonon propagation in silicon at frequencies up to 3 THz. These efforts culminated in a dramatic reduction in the thermal conductivity of silicon using phononic crystals by a factor of almost 30 as compared with the bulk value, and about 6 as compared with an unpatterned slab of the same thickness. This work represents a revolutionary advance in the engineering of thermoelectric materials for optimal, high-ZT performance. We have demonstrated the significant reduction of the thermal conductivity of silicon using phononic crystal structuring using MEMS-compatible fabrication techniques and in a planar platform that is amenable to integration with typical microelectronic systems. The measured reduction in thermal conductivity as compared to bulk silicon was about a factor of 20 in the cross-plane direction [26], and a factor of 6 in the in-plane direction. Since the electrical conductivity was only reduced by a corresponding factor of about 3 due to the removal of conductive material (i.e., porosity), and the Seebeck coefficient should remain constant as an intrinsic material property, this corresponds to an effective enhancement in ZT by a factor of 2. Given the number of papers in literature devoted to only a small, incremental change in ZT, the ability to boost the ZT of a material by a factor of 2 simply by reducing thermal conductivity is groundbreaking. The results in this work were obtained using silicon, a material that has benefitted from enormous interest in the microelectronics industry and that has a fairly large thermoelectric power factor. In addition, the techniques and scientific understanding developed in the research can be applied to a wide range of materials, with the caveat that the thermal conductivity of such a material be dominated by phonon, rather than electron, transport. In particular, this includes several thermoelectric materials with attractive properties at elevated temperatures (i.e., greater than room temperature), such as silicon germanium and silicon carbide. It is reasonable that phononic crystal patterning could be used for high-temperature thermoelectric devices using such materials, with applications in energy scavenging via waste-heat recovery and thermoelectric cooling for high-performance microelectronic circuits. The only part of the ZT picture missing in this work was the experimental measurement of the Seebeck coefficient of our phononic crystal devices. While a first-order approximation indicates that the Seebeck coefficient should not change significantly from that of bulk silicon, we were not able to actually verify this assumption within the timeframe of the project. Additionally, with regards to future high-temperature applications of this technology, we plan to measure the thermal conductivity reduction factor of our phononic crystals as elevated temperatures to confirm that it does not diminish, given that the nominal thermal conductivity of most semiconductors, including silicon, decreases with temperature above room temperature. We hope to have the opportunity to address these concerns and further advance the state-of-the-art of thermoelectric materials in future projects.

  16. Controlled growth of semiconductor crystals

    DOE Patents [OSTI]

    Bourret-Courchesne, E.D.

    1992-07-21

    A method is disclosed for growth of III-V, II-VI and related semiconductor single crystals that suppresses random nucleation and sticking of the semiconductor melt at the crucible walls. Small pieces of an oxide of boron B[sub x]O[sub y] are dispersed throughout the comminuted solid semiconductor charge in the crucible, with the oxide of boron preferably having water content of at least 600 ppm. The crucible temperature is first raised to a temperature greater than the melt temperature T[sub m1] of the oxide of boron (T[sub m1]=723 K for boron oxide B[sub 2]O[sub 3]), and the oxide of boron is allowed to melt and form a reasonably uniform liquid layer between the crucible walls and bottom surfaces and the still-solid semiconductor charge. The temperature is then raised to approximately the melt temperature T[sub m2] of the semiconductor charge material, and crystal growth proceeds by a liquid encapsulated, vertical gradient freeze process. About half of the crystals grown have a dislocation density of less than 1000/cm[sup 2]. If the oxide of boron has water content less than 600 ppm, the crucible material should include boron nitride, a layer of the inner surface of the crucible should be oxidized before the oxide of boron in the crucible charge is melted, and the sum of thicknesses of the solid boron oxide layer and liquid boron oxide layer should be at least 50 [mu]m. 7 figs.

  17. Controlled growth of semiconductor crystals

    DOE Patents [OSTI]

    Bourret-Courchesne, Edith D. (Richmond, CA)

    1992-01-01

    A method for growth of III-V, II-VI and related semiconductor single crystals that suppresses random nucleation and sticking of the semiconductor melt at the crucible walls. Small pieces of an oxide of boron B.sub.x O.sub.y are dispersed throughout the comminuted solid semiconductor charge in the crucible, with the oxide of boron preferably having water content of at least 600 ppm. The crucible temperature is first raised to a temperature greater than the melt temperature T.sub.m1 of the oxide of boron (T.sub.m1 =723.degree. K. for boron oxide B.sub.2 O.sub.3), and the oxide of boron is allowed to melt and form a reasonably uniform liquid layer between the crucible walls and bottom surfaces and the still-solid semiconductor charge. The temperature is then raised to approximately the melt temperature T.sub.m2 of the semiconductor charge material, and crystal growth proceeds by a liquid encapsulated, vertical gradient freeze process. About half of the crystals grown have a dislocation density of less than 1000/cm.sup.2. If the oxide of boron has water content less than 600 ppm, the crucible material should include boron nitride, a layer of the inner surface of the crucible should be oxidized before the oxide of boron in the crucible charge is melted, and the sum of thicknesses of the solid boron oxide layer and liquid boron oxide layer should be at least 50 .mu.m.

  18. BPS States, Crystals, and Matrices

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

    Sułkowski, Piotr

    2011-01-01

    We review free fermion, melting crystal, and matrix model representations of wall-crossing phenomena on local, toric Calabi-Yau manifolds. We consider both unrefined and refined BPS counting of closed BPS states involving D2- and D0-branes bound to a D6-brane, as well as open BPS states involving open D2-branes ending on an additional D4-brane. Appropriate limit of these constructions provides, among the others, matrix model representation of refined and unrefined topological string amplitudes.

  19. Florida Nuclear Profile - Crystal River

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

    Crystal River1" "Unit","Summer capacity (mw)","Net generation (thousand mwh)","Summer capacity factor (percent)","Type","Commercial operation date","License expiration date" 3,860,0,"--","PWR","application/vnd.ms-excel","application/vnd.ms-excel" ,860,0,"--" "Data for 2010" "1 Unit was offline in 2010 for repairs." "-- Not applicable.

  20. Crystallization and functionality of inorganic materials

    SciTech Connect (OSTI)

    Xue, Dongfeng, E-mail: dongfeng@ciac.jl.cn [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China) [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); School of Chemical Engineering, Dalian University of Technology, Dalian 116024 (China); Li, Keyan [School of Chemical Engineering, Dalian University of Technology, Dalian 116024 (China)] [School of Chemical Engineering, Dalian University of Technology, Dalian 116024 (China); Liu, Jun [Key Laboratory of Low Dimensional Materials and Application Technology, Ministry of Education, Faculty of Materials, Optoelectronics and Physics, Xiangtan University, 411105 (China)] [Key Laboratory of Low Dimensional Materials and Application Technology, Ministry of Education, Faculty of Materials, Optoelectronics and Physics, Xiangtan University, 411105 (China); Sun, Congting; Chen, Kunfeng [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China) [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); School of Chemical Engineering, Dalian University of Technology, Dalian 116024 (China)

    2012-10-15

    In this article, we briefly summarized our recent work on the studies of crystallization and functionality of inorganic materials. On the basis of the chemical bonding theory of single crystal growth, we can quantitatively simulate Cu{sub 2}O crystallization processes in solution system. We also kinetically controlled Cu{sub 2}O crystallization process in the reduction solution route. Lithium ion battery and supercapacitor performances of some oxides such as Co{sub 3}O{sub 4} and MnO{sub 2} were shown to elucidate the important effect of crystallization on functionality of inorganic materials. This work encourages us to create novel functionalities through the study of crystallization of inorganic materials, which warrants more chances in the field of functional materials.

  1. Edge rotational magnons in magnonic crystals

    SciTech Connect (OSTI)

    Lisenkov, Ivan Kalyabin, Dmitry; Moscow Institute of Physics and Technology, 9 Instituskij per., Dolgoprudny, 141700 Moscow Region ; Nikitov, Sergey; Moscow Institute of Physics and Technology, 9 Instituskij per., Dolgoprudny, 141700 Moscow Region; Saratov State University, 112 Bol'shaya Kazach'ya, Saratov 410012

    2013-11-11

    It is predicted that in 2D magnonic crystals the edge rotational magnons of forward volume magnetostatic spin waves can exist. Under certain conditions, locally bounded magnons may appear within the crystal consisting of the ferromagnetic matrix and periodically inserted magnetic/non-magnetic inclusions. It is also shown that interplay of different resonances in 2D magnonic crystal may provide conditions for spin wave modes existence with negative group velocity.

  2. Crystallizing Transmembrane Peptides in Lipidic Mesophases (Journal

    Office of Scientific and Technical Information (OSTI)

    Article) | SciTech Connect Crystallizing Transmembrane Peptides in Lipidic Mesophases Citation Details In-Document Search Title: Crystallizing Transmembrane Peptides in Lipidic Mesophases Structure determination of membrane proteins by crystallographic means has been facilitated by crystallization in lipidic mesophases. It has been suggested, however, that this so-called in meso method, as originally implemented, would not apply to small protein targets having {le}4 transmembrane crossings.

  3. Kondo behavior, ferromagnetic correlations, and crystal fields...

    Office of Scientific and Technical Information (OSTI)

    Subject: 36 MATERIALS SCIENCE; CERIUM ALLOYS; INDIUM ALLOYS; TIN ALLOYS; CRYSTAL FIELD; ENTROPY; FERMIONS; GROUND STATES; KONDO EFFECT; MAGNETIC SUSCEPTIBILITY; NEUTRON ...

  4. Silicon Crystals Inc | Open Energy Information

    Open Energy Info (EERE)

    Zip: 95742 Product: Supplier of semi-conductor grade silicon for applications that demand unusual shapes and sizes. References: Silicon Crystals Inc1 This article is a stub....

  5. Automated macromolecular crystal detection system and method

    DOE Patents [OSTI]

    Christian, Allen T. (Tracy, CA); Segelke, Brent (San Ramon, CA); Rupp, Bernard (Livermore, CA); Toppani, Dominique (Fontainebleau, FR)

    2007-06-05

    An automated macromolecular method and system for detecting crystals in two-dimensional images, such as light microscopy images obtained from an array of crystallization screens. Edges are detected from the images by identifying local maxima of a phase congruency-based function associated with each image. The detected edges are segmented into discrete line segments, which are subsequently geometrically evaluated with respect to each other to identify any crystal-like qualities such as, for example, parallel lines, facing each other, similarity in length, and relative proximity. And from the evaluation a determination is made as to whether crystals are present in each image.

  6. Watching a Liquid-Crystal Helix Unwind

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

    Chirality, the absence of inversion symmetry, plays an important role in chemistry, biology, and materials science. Introducing molecular chirality into a liquid crystal may...

  7. Crystal Structures of Lipoglycopeptide Antibiotic Deacetylases...

    Office of Scientific and Technical Information (OSTI)

    N-acetyl-glucosaminyl pseudoaglycone is deacetylated prior to long chain hydrocarbon attachment. Here we present several high-resolution crystal structures of the pseudoaglycone...

  8. Crystallization of Enantiomerically Pure Proteins from Quasi...

    Office of Scientific and Technical Information (OSTI)

    Crystallization of Enantiomerically Pure Proteins from Quasi-Racemic Mixtures: Structure Determination by X-Ray Diffraction of Isotope-Labeled Ester Insulin and Human Insulin ...

  9. Ribosome engineering to promote new crystal forms

    SciTech Connect (OSTI)

    Selmer, Maria; Gao, Yong-Gui; Weixlbaumer, Albert; Ramakrishnan, V.

    2012-05-01

    Truncation of ribosomal protein L9 in T. thermophilus allows the generation of new crystal forms and the crystallization of ribosomeGTPase complexes. Crystallographic studies of the ribosome have provided molecular details of protein synthesis. However, the crystallization of functional complexes of ribosomes with GTPase translation factors proved to be elusive for a decade after the first ribosome structures were determined. Analysis of the packing in different 70S ribosome crystal forms revealed that regardless of the species or space group, a contact between ribosomal protein L9 from the large subunit and 16S rRNA in the shoulder of a neighbouring small subunit in the crystal lattice competes with the binding of GTPase elongation factors to this region of 16S rRNA. To prevent the formation of this preferred crystal contact, a mutant strain of Thermus thermophilus, HB8-MRCMSAW1, in which the ribosomal protein L9 gene has been truncated was constructed by homologous recombination. Mutant 70S ribosomes were used to crystallize and solve the structure of the ribosome with EF-G, GDP and fusidic acid in a previously unobserved crystal form. Subsequent work has shown the usefulness of this strain for crystallization of the ribosome with other GTPase factors.

  10. Crystal Solar Inc | Open Energy Information

    Open Energy Info (EERE)

    Solar Inc Jump to: navigation, search Name: Crystal Solar Inc. Place: Santa Clara, California Zip: 94054 Sector: Solar Product: California-based developer of silicon solar cells....

  11. Nanoscopic Manipulation and Imaging of Liquid Crystals

    SciTech Connect (OSTI)

    Rosenblatt, Charles S.

    2014-02-04

    This is the final project report. The projects goals centered on nanoscopic imaging and control of liquid crystals and surfaces. We developed and refined techniques to control liquid crystal orientation at surfaces with resolution as small as 25 nm, we developed an optical imaging technique that we call Optical Nanotomography that allows us to obtain images inside liquid crystal films with resolution of 60 x 60 x 1 nm, and we opened new thrust areas related to chirality and to liquid crystal/colloid composites.

  12. JX Crystals Inc | Open Energy Information

    Open Energy Info (EERE)

    Solar Product: JX Crystals designs and manufactures thermophotovoltaic gallium-antimonide cells for solar applications. Coordinates: 47.530095, -122.033799 Show Map Loading...

  13. Crystal Structures of Phosphite Dehydrogenase Provide Insights...

    Office of Scientific and Technical Information (OSTI)

    SciTech Connect Search Results Journal Article: Crystal Structures of Phosphite Dehydrogenase Provide Insights into Nicotinamide Cofactor Regeneration Citation Details In-Document ...

  14. Watching a Liquid-Crystal Helix Unwind

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

    plays an important role in chemistry, biology, and materials science. Introducing molecular chirality into a liquid crystal may lead to a twisting force that can modify the...

  15. Method For Screening Microcrystallizations For Crystal Formation

    DOE Patents [OSTI]

    Santarsiero, Bernard D. (Chicago, IL), Stevens, Raymond C. (La Jolla, CA), Schultz, Peter G. (La Jolla, CA), Jaklevic, Joseph M. (Lafayette, CA), Yegian, Derek T. (Oakland, CA), Cornell, Earl W. (Antioch, CA), Nordmeyer, Robert A. (San Leandro, CA)

    2003-10-07

    A method is provided for performing array microcrystallizations to determine suitable crystallization conditions for a molecule, the method comprising: forming an array of microcrystallizations, each microcrystallization comprising a drop comprising a mother liquor solution whose composition varies within the array and a molecule to be crystallized, the drop having a volume of less than 1 microliter; storing the array of microcrystallizations under conditions suitable for molecule crystals to form in the drops in the array; and detecting molecule crystal formation in the drops by taking images of the drops.

  16. Crystal growth and annealing for minimized residual stress

    DOE Patents [OSTI]

    Gianoulakis, Steven E.

    2002-01-01

    A method and apparatus for producing crystals that minimizes birefringence even at large crystal sizes, and is suitable for production of CaF.sub.2 crystals. The method of the present invention comprises annealing a crystal by maintaining a minimal temperature gradient in the crystal while slowly reducing the bulk temperature of the crystal. An apparatus according to the present invention includes a thermal control system added to a crystal growth and annealing apparatus, wherein the thermal control system allows a temperature gradient during crystal growth but minimizes the temperature gradient during crystal annealing.

  17. Method of making coherent multilayer crystals

    DOE Patents [OSTI]

    Schuller, Ivan K. (Woodridge, IL); Falco, Charles M. (Woodridge, IL)

    1984-01-01

    A new material consisting of a coherent multilayer crystal of two or more elements where each layer is composed of a single element. Each layer may vary in thickness from about 2 .ANG. to 2500 .ANG.. The multilayer crystals are prepared by sputter deposition under conditions which slow the sputtered atoms to near substrate temperatures before they contact the substrate.

  18. Ultratough single crystal boron-doped diamond

    DOE Patents [OSTI]

    Hemley, Russell J [Carnegie Inst. for Science, Washington, DC (United States); Mao, Ho-Kwang [Carnegie Inst. for Science, Washington, DC (United States); Yan, Chih-Shiue [Carnegie Inst. for Science, Washington, DC (United States); Liang, Qi [Carnegie Inst. for Science, Washington, DC (United States)

    2015-05-05

    The invention relates to a single crystal boron doped CVD diamond that has a toughness of at least about 22 MPa m.sup.1/2. The invention further relates to a method of manufacturing single crystal boron doped CVD diamond. The growth rate of the diamond can be from about 20-100 .mu.m/h.

  19. Photonic crystal scintillators and methods of manufacture

    DOE Patents [OSTI]

    Torres, Ricardo D.; Sexton, Lindsay T.; Fuentes, Roderick E.; Cortes-Concepcion, Jose

    2015-08-11

    Photonic crystal scintillators and their methods of manufacture are provided. Exemplary methods of manufacture include using a highly-ordered porous anodic alumina membrane as a pattern transfer mask for either the etching of underlying material or for the deposition of additional material onto the surface of a scintillator. Exemplary detectors utilizing such photonic crystal scintillators are also provided.

  20. Coherent multilayer crystals and method of making

    DOE Patents [OSTI]

    Schuller, I.K.; Falco, C.M.

    1980-10-30

    A new material is described consisting of a coherent multilayer crystal of two or more elements where each layer is composed of a single element. Each layer may vary in thickness from about 2 A to 2500 A. The multilayer crystals are prepared by sputter deposition under conditions which slow the sputtered atoms to near substrate temperatures before they contact the substrate.

  1. Ames Lab 101: Single Crystal Growth

    ScienceCinema (OSTI)

    Schlagel, Deborah

    2014-06-04

    Ames Laboratory scientist Deborah Schlagel talks about the Lab's research in growing single crystals of various metals and alloys. The single crystal samples are vital to researchers' understanding of the characteristics of a materials and what gives these materials their particular properties.

  2. Growth Of Oriented Crystals At Polymerized Membranes

    DOE Patents [OSTI]

    Charych, Deborah H. (Albany, CA), Berman, Amir (Ben-Shiva, IL)

    2000-01-25

    The present invention relates to methods and compositions for the growth and alignment of crystals at biopolymeric films. The methods and compositions of the present invention provide means to generate a variety of dense crystalline ceramic films, with totally aligned crystals, at low temperatures and pressures, suitable for use with polymer and plastic substrates.

  3. Liquid crystal-templated conducting organic polymers

    DOE Patents [OSTI]

    Stupp, Samuel I.; Hulvat, James F.

    2004-01-20

    A method of preparing a conductive polymeric film, includes providing a liquid crystal phase comprising a plurality of hydrophobic cores, the phase on a substrate, introducing a hydrophobic component to the phase, the component a conductive polymer precursor, and applying an electric potential across the liquid crystal phase, the potential sufficient to polymerize the said precursor.

  4. THE TWO STAGE CRYSTAL COLLIMATOR FOR RHIC.

    SciTech Connect (OSTI)

    FLILLER, R.P. III; DREES, A.; GASSNER, D.; HAMMONS, L.; MCINTYRE, G.; TRBOJEVIC, D.; BIRYUKOV, V.; CHESNOKOV, Y.; TEREKHOV, V.

    2001-06-18

    The use of a two stage crystal collimation system in the RHIC yellow ring is examined. The system includes a copper beam scraper and a bent silicon crystal. While scrapers were installed in both of the RHIC rings before the year 2000 run, the crystal is installed for the 2001 run in one ring only, forming a two stage collimation system there. We present simulations of the expected channeling through the bent silicon crystal for both protons and gold ions with various beam parameters. This gives a picture of the particle losses around the ring, and the expected channeling efficiency. These results are then used to optimize the beam parameters in the area of the crystal to obtain maximum channeling efficiency, minimize out-scattering in the secondary collimator, and reduce beam halo.

  5. Liquid crystal device and method thereof

    DOE Patents [OSTI]

    Shiyanovskii, Sergij V; Gu, Mingxia; Lavrentovich, Oleg D

    2012-10-23

    The invention provides a liquid crystal device and method thereof. Subsequent to applying a first electrical voltage on a liquid crystal to induce a reorientation of the liquid crystal, a second electrical voltage with proper polarity is applied on the liquid crystal to assist the relaxation of the reorientation that was induced by the first electrical voltage. The "switch-off" phase of the liquid crystal can therefore be accelerated or temporally shortened, and the device can exhibit better performance such as fast response to on/off signals. The invention can be widely used LCD, LC shutter, LC lens, spatial light modulator, telecommunication device, tunable filter, beam steering device, and electrically driven LC device, among others.

  6. World's largest single crystal of gold verified at Los Alamos

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

    World's largest single crystal of gold verified at Los Alamos World's largest single crystal of gold verified at Los Alamos The SCD instrument is used to determine the periodic atomic arrangement or crystal structure of single crystals, both natural and synthetic. April 7, 2014 Neutron diffraction data collected on the single-crystal diffraction (SCD) instrument at the Lujan Center, from the Venezuelan gold sample, indicate that the sample is a single crystal. Neutron diffraction data collected

  7. Channeling through Bent Crystals (Technical Report) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    SciTech Connect Search Results Technical Report: Channeling through Bent Crystals Citation Details In-Document Search Title: Channeling through Bent Crystals Bent crystals have demonstrated potential for use in beam collimation. A process called channeling is when accelerated particle beams are trapped by the nuclear potentials in the atomic planes within a crystal lattice. If the crystal is bent then the particles can follow the bending angle of the crystal. There are several different effects

  8. Channeling through Bent Crystals (Technical Report) | SciTech Connect

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

    Channeling through Bent Crystals Citation Details In-Document Search Title: Channeling through Bent Crystals Bent crystals have demonstrated potential for use in beam collimation. A process called channeling is when accelerated particle beams are trapped by the nuclear potentials in the atomic planes within a crystal lattice. If the crystal is bent then the particles can follow the bending angle of the crystal. There are several different effects that are observed when particles travel through a

  9. Crystal Hot Springs Pool & Spa Low Temperature Geothermal Facility...

    Open Energy Info (EERE)

    Hot Springs Pool & Spa Low Temperature Geothermal Facility Jump to: navigation, search Name Crystal Hot Springs Pool & Spa Low Temperature Geothermal Facility Facility Crystal Hot...

  10. Crystallizing Membrane Proteins in Lipidic Mesophases. A Host...

    Office of Scientific and Technical Information (OSTI)

    Crystallizing Membrane Proteins in Lipidic Mesophases. A Host Lipid Screen Citation Details In-Document Search Title: Crystallizing Membrane Proteins in Lipidic Mesophases. A Host ...

  11. Low Temperature Crystal Structure and Magnetic Properties of...

    Office of Scientific and Technical Information (OSTI)

    Low Temperature Crystal Structure and Magnetic Properties of RAl2 Citation Details In-Document Search Title: Low Temperature Crystal Structure and Magnetic Properties of RAl2 Low ...

  12. Imaging the oblique propagation of electrons in germanium crystals...

    Office of Scientific and Technical Information (OSTI)

    electrons in germanium crystals at low temperature and low electric field This content ... electrons in germanium crystals at low temperature and low electric field Authors: ...

  13. Crystallization and Mechanical Properties of Poly(l-lactide)...

    Office of Scientific and Technical Information (OSTI)

    Crystallization and Mechanical Properties of Poly(l-lactide)-Based RubberySemicrystalline Multiblock Copolymers Citation Details In-Document Search Title: Crystallization and...

  14. World's largest single crystal of gold verified by Los Alamos...

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

    Los Alamos verifies largest single gold crystal World's largest single crystal of gold verified by Los Alamos instruments Using Lujan Center's HIPPO instrument, researchers probed...

  15. Crystal structure of a ;#8203;BRAF kinase domain monomer explains...

    Office of Scientific and Technical Information (OSTI)

    Crystal structure of a ;8203;BRAF kinase domain monomer explains basis for allosteric regulation Citation Details In-Document Search Title: Crystal structure of a ;8203;BRAF ...

  16. DOE Science Showcase - Bent Crystals | OSTI, US Dept of Energy...

    Office of Scientific and Technical Information (OSTI)

    Related Research Information in DOE Databases In the OSTI Collections: Bent Crystals, Dr. William Watson Search Results for "Bent Crystals", E-Print Network Channeling through Bent ...

  17. Crystal Crane Hot Springs Pool & Spa Low Temperature Geothermal...

    Open Energy Info (EERE)

    Crystal Crane Hot Springs Pool & Spa Low Temperature Geothermal Facility Jump to: navigation, search Name Crystal Crane Hot Springs Pool & Spa Low Temperature Geothermal Facility...

  18. Coherent bremsstrahlung in a bent crystal

    SciTech Connect (OSTI)

    Bondarenco, M. V.

    2010-05-15

    Coherent radiation spectrum from high energy e{sup {+-}}in a bent crystal with arbitrary curvature distribution along the longitudinal coordinate is evaluated, based on the stationary phase approximation. For a uniformly bent crystal a closed-form expression for the spectrum is derived. The spectrum features include a dip at its beginning and the sharp end, which may split into two breaks depending on the particle incidence angle. Estimates of nondipole radiation and multiple scattering effects are given. The value for the crystal bending angle at which the dipole coherent bremsstrahlung theory holds best appears to be {approx}10{sup -4} rad.

  19. Laser Crystallization of Phase Change Material

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

    Geoffrey Campbell is the Principal Investigator for Laser Crystallization of Phase Change Material LLNL BES Programs Highlight Laser Crystallization of Phase Change Material False color images of growth of crystalline GeTe (yellow) into amorphous GeTe (blue) in a series of 17.5 ns images during crystallization induced by a 12 ns laser pulse M.K. Santala, B.W. Reed, S. Raoux, T. Topuria, T. LaGrange, and G.H. Campbell, "Irreversible Reactions Studied with Nanosecond TEM Movies: Laser

  20. Crystal growth under external electric fields

    SciTech Connect (OSTI)

    Uda, Satoshi; Koizumi, Haruhiko; Nozawa, Jun; Fujiwara, Kozo

    2014-10-06

    This is a review article concerning the crystal growth under external electric fields that has been studied in our lab for the past 10 years. An external field is applied electrostatically either through an electrically insulating phase or a direct injection of an electric current to the solid-interface-liquid. The former changes the chemical potential of both solid and liquid and controls the phase relationship while the latter modifies the transport and partitioning of ionic solutes in the oxide melt during crystallization and changes the solute distribution in the crystal.

  1. Structural characterization of thin film photonic crystals

    SciTech Connect (OSTI)

    Subramania, G.; Biswas, R.; Constant, K.; Sigalas, M. M.; Ho, K. M.

    2001-06-15

    We quantitatively analyze the structure of thin film inverse-opal photonic crystals composed of ordered arrays of air pores in a background of titania. Ordering of the sphere template and introduction of the titania background were performed simultaneously in the thin film photonic crystals. Nondestructive optical measurements of backfilling with high refractive index liquids, angle-resolved reflectivity, and optical spectroscopy were combined with band-structure calculations. The analysis reveals a thin film photonic crystal structure with a very high filling fraction (92{endash}94%) of air and a substantial compression along the c axis ({similar_to}22{endash}25%).

  2. CRYSTAL CHEMISTRY OF HYDROUS MINERALS

    SciTech Connect (OSTI)

    Y. ZHAO; ET AL

    2001-02-01

    Hydrogen has long been appreciated for its role in geological processes of the Earth's crust. However, its role in Earth's deep interior has been neglected in most geophysical thinking. Yet it is now believed that most of our planet's hydrogen may be locked up in high pressure phases of hydrous silicate minerals within the Earth's mantle. This rocky interior (approximately 7/8 of Earth's volume) is conjectured to contain 1-2 orders of magnitude more water than the more obvious oceans (the ''hydrosphere'') and atmosphere. This project is aimed at using the capability of neutron scattering from hydrogen to study the crystal chemistry and stability of hydrogen-bearing minerals at high pressures and temperatures. At the most basic level this is a study of the atomic position and hydrogen bond itself. We have conducted experimental runs on hydrous minerals under high pressure and high temperature conditions. The crystallographic structure of hydrous minerals at extreme conditions and its structural stability, and hydrogen bond at high P-T conditions are the fundamental questions to be addressed. The behavior of the hydrous minerals in the deep interior of the Earth has been discussed.

  3. Watching a Liquid-Crystal Helix Unwind

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

    of why the development, by Zhu et al., of a technique allowing direct measurement and control of liquid-crystal properties is important. The NOBOW molecular structure and a...

  4. Thermophysical parameters of the LBO crystal

    SciTech Connect (OSTI)

    Grechin, Sergei G; Zuev, A V; Fokin, A S; Kokh, Aleksandr E; Moiseev, N V; Popov, Petr A; Sidorov, Aleksei A

    2010-08-27

    The thermophysical parameters (linear thermal expansion coefficients, thermal conductivities, and heat capacity) of the lithium triborate (LBO) crystal are measured and compared with previously published data. (nonlinear-optics phenomena)

  5. Method for solid state crystal growth

    DOE Patents [OSTI]

    Nolas, George S.; Beekman, Matthew K.

    2013-04-09

    A novel method for high quality crystal growth of intermetallic clathrates is presented. The synthesis of high quality pure phase crystals has been complicated by the simultaneous formation of both clathrate type-I and clathrate type-II structures. It was found that selective, phase pure, single-crystal growth of type-I and type-II clathrates can be achieved by maintaining sufficient partial pressure of a chemical constituent during slow, controlled deprivation of the chemical constituent from the primary reactant. The chemical constituent is slowly removed from the primary reactant by the reaction of the chemical constituent vapor with a secondary reactant, spatially separated from the primary reactant, in a closed volume under uniaxial pressure and heat to form the single phase pure crystals.

  6. Watching a Liquid-Crystal Helix Unwind

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

    In a chiral liquid crystal, stacked molecular layers form a twist-a useful property in LCD technology. NOBOW transforms from the B4 (helical) phase to the B2 (flat) phase at 142...

  7. Watching a Liquid-Crystal Helix Unwind

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

    but are best known for the liquid-crystal displays that drive the billion-dollar smartphone and flat-screen industries. Chirality, the absence of inversion symmetry, plays an...

  8. Phononic Crystals: Engineering the Flow of Heat

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

    ... Phononic Crystals: Engineering the Flow of Heat A Sandia-led research team has, for the first time, observed the coherent propagation of thermal phonons in silicon at room ...

  9. Neutron detection with single crystal organic scintillators

    SciTech Connect (OSTI)

    Zaitseva, N; Newby, J; Hamel, S; Carman, L; Faust, M; Lordi, V; Cherepy, N; Stoeffl, W; Payne, S

    2009-07-15

    Detection of high-energy neutrons in the presence of gamma radiation background utilizes pulse-shape discrimination (PSD) phenomena in organics studied previously only with limited number of materials, mostly liquid scintillators and single crystal stilbene. The current paper presents the results obtained with broader varieties of luminescent organic single crystals. The studies involve experimental tools of crystal growth and material characterization in combination with the advanced computer modeling, with the final goal of better understanding the relevance between the nature of the organic materials and their PSD properties. Special consideration is given to the factors that may diminish or even completely obscure the PSD properties in scintillating crystals. Among such factors are molecular and crystallographic structures that determine exchange coupling and exciton mobility in organic materials and the impurity effect discussed on the examples of trans-stilbene, bibenzyl, 9,10-diphenylanthracene and diphenylacetylene.

  10. Crystal J. Rodarte-Romero-Engineering

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

    Today, more than 13,000 people cross this bridge daily by bike, foot or car. And Crystal J. Rodarte- Romero's job is to ensure that the 63-year-old bridge remains safe. The Lab's...

  11. Changes in mobility of plastic crystal ethanol during its transformation into the monoclinic crystal state

    SciTech Connect (OSTI)

    Sanz, Alejandro Nogales, Aurora; Ezquerra, Tiberio A.; Puente-Orench, Ins; Instituto de Ciencia de Materiales de Aragn, ICMA-CSIC, Pedro Cerbuna 12, 50009 Zaragoza ; Jimnez-Ruiz, Mnica

    2014-02-07

    Transformation of deuterated ethanol from the plastic crystal phase into the monoclinic one is investigated by means of a singular setup combining simultaneously dielectric spectroscopy with neutron diffraction. We postulate that a dynamic transition from plastic crystal to supercooled liquid-like configuration through a deep reorganization of the hydrogen-bonding network must take place as a previous step of the crystallization process. Once these precursor regions are formed, subsequent crystalline nucleation and growth develop with time.

  12. Purification, crystallization and structural elucidation of

    Office of Scientific and Technical Information (OSTI)

    D-galactaro-1,4-lactone cycloisomerase from Agrobacterium tumefaciens involved in pectin degradation (Journal Article) | SciTech Connect Purification, crystallization and structural elucidation of D-galactaro-1,4-lactone cycloisomerase from Agrobacterium tumefaciens involved in pectin degradation Citation Details In-Document Search Title: Purification, crystallization and structural elucidation of D-galactaro-1,4-lactone cycloisomerase from Agrobacterium tumefaciens involved in pectin

  13. Macromolecular Diffractive Imaging using Disordered Crystals | Stanford

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

    Synchrotron Radiation Lightsource Macromolecular Diffractive Imaging using Disordered Crystals Wednesday, March 9, 2016 - 3:00pm SLAC, Redtail Hawk Conference Room 108A Speaker: Henry Chapman, Center for Free-Electron Laser Science, DESY Program Description X-ray crystallography suffers from the well-known phase problem. This means that it is not possible to reconstruct an image of a molecule from its crystal diffraction pattern of Bragg peaks without additional knowledge or assumptions

  14. Enhancement of crystal homogeneity of protein crystals under application of an external alternating current electric field

    SciTech Connect (OSTI)

    Koizumi, H.; Uda, S.; Fujiwara, K.; Nozawa, J.; Tachibana, M.; Kojima, K.

    2014-10-06

    X-ray diffraction rocking-curve measurements were performed on tetragonal hen egg white (HEW) lysozyme crystals grown with and without the application of an external alternating current (AC) electric field. The crystal quality was assessed by the full width at half maximum (FWHM) value for each rocking curve. For two-dimensional maps of the FWHMs measured on the 440 and the 12 12 0 reflection, the crystal homogeneity was improved under application of an external electric field at 1 MHz, compared with that without. In particular, the significant improvement of the crystal homogeneity was observed for the 12 12 0 reflection.

  15. Method for reducing energy losses in laser crystals

    DOE Patents [OSTI]

    Atherton, L.J.; DeYoreo, J.J.; Roberts, D.H.

    1992-03-24

    A process for reducing energy losses in crystals is disclosed which comprises: a. heating a crystal to a temperature sufficiently high as to cause dissolution of microscopic inclusions into the crystal, thereby converting said inclusions into point-defects, and b. maintaining said crystal at a given temperature for a period of time sufficient to cause said point-defects to diffuse out of said crystal. Also disclosed are crystals treated by the process, and lasers utilizing the crystals as a source of light. 12 figs.

  16. Method for reducing energy losses in laser crystals

    DOE Patents [OSTI]

    Atherton, L. Jeffrey (Pleasanton, CA); DeYoreo, James J. (Livermore, CA); Roberts, David H. (Pleasanton, CA)

    1992-01-01

    A process for reducing energy losses in crystals is disclosed which comprises: a. heating a crystal to a temperature sufficiently high as to cause dissolution of microscopic inclusions into the crystal, thereby converting said inclusions into point-defects, and b. maintaining said crystal at a given temperature for a period of time sufficient to cause said point-defects to diffuse out of said crystal. Also disclosed are crystals treated by the process, and lasers utilizing the crystals as a source of light.

  17. Deflection of light by using tungsten bronze crystals

    SciTech Connect (OSTI)

    Jelsma, L.F.; McWright, G.M.; Schumacher, F.A.; Neurgaonkar, R.R.

    1988-07-05

    This paper reports our preliminary results on an electrooptical light deflector for streak camera applications that uses tungsten bronze SBN:60% crystals. We found the performance of these ferroelectric crystals to be an order of magnitude better than the best LiNbO/sub 3/ crystals currently available. We discuss the theory and performance of this crystal as well as other bronze crystals for application to the streak camera. 8 refs., 5 figs., 2 tabs.

  18. Physical Modeling of Spinel Crystals Settling at Low Reynolds Numbers

    Office of Scientific and Technical Information (OSTI)

    (Journal Article) | SciTech Connect Journal Article: Physical Modeling of Spinel Crystals Settling at Low Reynolds Numbers Citation Details In-Document Search Title: Physical Modeling of Spinel Crystals Settling at Low Reynolds Numbers The crystallization of large octahedral crystals of spinel during the high-level waste (HLW) vitrification process poses a potential danger to electrically heated ceramic melters. Large spinel crystals rapidly settle under gravitational attraction and

  19. Membrane Protein Crystallization in Lipidic Mesophases. Hosting Lipid

    Office of Scientific and Technical Information (OSTI)

    Effects on the Crystallization and Structure of a Transmembrane Peptide (Journal Article) | SciTech Connect Membrane Protein Crystallization in Lipidic Mesophases. Hosting Lipid Effects on the Crystallization and Structure of a Transmembrane Peptide Citation Details In-Document Search Title: Membrane Protein Crystallization in Lipidic Mesophases. Hosting Lipid Effects on the Crystallization and Structure of a Transmembrane Peptide Gramicidin is an apolar pentadecapeptide antibiotic

  20. ARC will make tiny "movies" of thermonuclear and stockpile experiments...

    National Nuclear Security Administration (NNSA)

    simulations Consortium Led by University of California, Berkeley Awarded 25M NNSA Grant for Nuclear Science and Security Research Final row of solar panels installed at Livermore...

  1. Moving microswimmers with tiny swirling flows | Argonne National...

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

    Normally the bacteria swim randomly; but when scientists spun the particle by applying a rotating magnetic field, the swimmers shot away from the center, like a school of fish that ...

  2. Sandia Energy - Sandia Labs Harnesses the Sun's Energy with Tiny...

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

    Home Renewable Energy Energy Facilities News News & Events Concentrating Solar Power Solar Systems Analysis National Solar Thermal Test Facility Materials Science Systems...

  3. Tiny magnets could work in sensors, information encoding

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

    headline to go to original article at phys.org. "Each nano-island is similar to a refrigerator magnet, with a north and a south pole at its tips," said Los Alamos physicist...

  4. Imager Spots and Samples Tiny Tumors | Jefferson Lab

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

    at Jefferson Lab, West Virginia University and the University of Maryland School of Medicine. The PEMPET system is designed for detecting and guiding the biopsies of suspicious...

  5. Good hair day: New technique grows tiny 'hairy' materials at...

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

    Louise Lerner at (630) 252-5526 or media@anl.gov. Connect Find an Argonne expert by subject. Follow Argonne on Twitter, Facebook, Google+ and LinkedIn. For inquiries on...

  6. Magnetic dipole interactions in crystals

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

    Johnston, David

    2016-01-13

    The influence of magnetic dipole interactions (MDIs) on the magnetic properties of local-moment Heisenberg spin systems is investigated. A general formulation is presented for calculating the eigenvalues λ and eigenvectors μ ˆ of the MDI tensor of the magnetic dipoles in a line (one dimension, 1D), within a circle (2D) or a sphere (3D) of radius r surrounding a given moment μ → i for given magnetic propagation vectors k for collinear and coplanar noncollinear magnetic structures on both Bravais and non-Bravais spin lattices. Results are calculated for collinear ordering on 1D chains, 2D square and simple-hexagonal (triangular) Bravais lattices,more » 2D honeycomb and kagomé non-Bravais lattices, and 3D cubic Bravais lattices. The λ and μ ˆ values are compared with previously reported results. Calculations for collinear ordering on 3D simple tetragonal, body-centered tetragonal, and stacked triangular and honeycomb lattices are presented for c/a ratios from 0.5 to 3 in both graphical and tabular form to facilitate comparison of experimentally determined easy axes of ordering on these Bravais lattices with the predictions for MDIs. Comparisons with the easy axes measured for several illustrative collinear antiferromagnets (AFMs) are given. The calculations are extended to the cycloidal noncollinear 120 ° AFM ordering on the triangular lattice where λ is found to be the same as for collinear AFM ordering with the same k. The angular orientation of the ordered moments in the noncollinear coplanar AFM structure of GdB 4 with a distorted stacked 3D Shastry-Sutherland spin-lattice geometry is calculated and found to be in disagreement with experimental observations, indicating the presence of another source of anisotropy. Similar calculations for the undistorted 2D and stacked 3D Shastry-Sutherland lattices are reported. The thermodynamics of dipolar magnets are calculated using the Weiss molecular field theory for quantum spins, including the magnetic transition temperature T m and the ordered moment, magnetic heat capacity, and anisotropic magnetic susceptibility χ versus temperature T . The anisotropic Weiss temperature θ p in the Curie-Weiss law for T>T m is calculated. A quantitative study of the competition between FM and AFM ordering on cubic Bravais lattices versus the demagnetization factor in the absence of FM domain effects is presented. The contributions of Heisenberg exchange interactions and of the MDIs to T m and to θ p are found to be additive, which simplifies analysis of experimental data. Some properties in the magnetically-ordered state versus T are presented, including the ordered moment and magnetic heat capacity and, for AFMs, the dipolar anisotropy of the free energy and the perpendicular critical field. The anisotropic χ for dipolar AFMs is calculated both above and below the Néel temperature T N and the results are illustrated for a simple tetragonal lattice with c/a>1, c/a=1 (cubic), and c/a<1 , where a change in sign of the χ anisotropy is found at c/a=1 . Finally, following the early work of Keffer [Phys. Rev. 87, 608 (1952)], the dipolar anisotropy of χ above T N =69 K of the prototype collinear Heisenberg-exchange-coupled tetragonal compound MnF 2 is calculated and found to be in excellent agreement with experimental single-crystal literature data above 130 K, where the smoothly increasing deviation of the experimental data from the theory on cooling from 130 K to T N is deduced to arise from dynamic short-range collinear c -axis AFM ordering in this temperature range driven by the exchange interactions.« less

  7. Ultrasonically assisted deposition of colloidal crystals

    SciTech Connect (OSTI)

    Wollmann, Sabine; Patel, Raj B.; Wixforth, Achim; Krenner, Hubert J.

    2014-07-21

    Colloidal particles are a versatile physical system which have found uses across a range of applications such as the simulation of crystal kinetics, etch masks for fabrication, and the formation of photonic band-gap structures. Utilization of colloidal particles often requires a means to produce highly ordered, periodic structures. One approach is the use of surface acoustic waves (SAWs) to direct the self-assembly of colloidal particles. Previous demonstrations using standing SAWs were shown to be limited in terms of crystal size and dimensionality. Here, we report a technique to improve the spatial alignment of colloidal particles using traveling SAWs. Through control of the radio frequency power, which drives the SAW, we demonstrate enhanced quality and dimensionality of the crystal growth. We show that this technique can be applied to a range of particle sizes in the ?m-regime and may hold potential for particles in the sub-?m-regime.

  8. Density functional theory for carbon dioxide crystal

    SciTech Connect (OSTI)

    Chang, Yiwen; Mi, Jianguo Zhong, Chongli

    2014-05-28

    We present a density functional approach to describe the solid?liquid phase transition, interfacial and crystal structure, and properties of polyatomic CO{sub 2}. Unlike previous phase field crystal model or density functional theory, which are derived from the second order direct correlation function, the present density functional approach is based on the fundamental measure theory for hard-sphere repulsion in solid. More importantly, the contributions of enthalpic interactions due to the dispersive attractions and of entropic interactions arising from the molecular architecture are integrated in the density functional model. Using the theoretical model, the predicted liquid and solid densities of CO{sub 2} at equilibrium triple point are in good agreement with the experimental values. Based on the structure of crystal-liquid interfaces in different planes, the corresponding interfacial tensions are predicted. Their respective accuracies need to be tested.

  9. Platinum Nanoclusters Out-Perform Single Crystals

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

    Platinum Nanoclusters Out-Perform Single Crystals Platinum Nanoclusters Out-Perform Single Crystals Print Wednesday, 27 October 2010 00:00 When it comes to metal catalysts, platinum is the standard. However, at about $2,000 an ounce, the high cost of the raw material presents major challenges for the future wide-scale use of platinum in fuel cells. Berkeley Lab research suggests that one possible way to meet these challenges is to think small. Researchers from Berkeley Lab's Materials Sciences

  10. Algorithmic crystal chemistry: A cellular automata approach

    SciTech Connect (OSTI)

    Krivovichev, S. V.

    2012-01-15

    Atomic-molecular mechanisms of crystal growth can be modeled based on crystallochemical information using cellular automata (a particular case of finite deterministic automata). In particular, the formation of heteropolyhedral layered complexes in uranyl selenates can be modeled applying a one-dimensional three-colored cellular automaton. The use of the theory of calculations (in particular, the theory of automata) in crystallography allows one to interpret crystal growth as a computational process (the realization of an algorithm or program with a finite number of steps).

  11. Optical amplification enhancement in photonic crystals

    SciTech Connect (OSTI)

    Sapienza, R.; Leonetti, M.; Froufe-Perez, L. S.; Galisteo-Lopez, J. F.; Lopez, C.; Conti, C.

    2011-02-15

    Improving and controlling the efficiency of a gain medium is one of the most challenging problems of laser research. By measuring the gain length in an opal-based photonic crystal doped with laser dye, we demonstrate that optical amplification is more than twenty-fold enhanced along the {Gamma}-K symmetry directions of the face-centered-cubic photonic crystal. These results are theoretically explained by directional variations of the density of states, providing a quantitative connection between density of the states and light amplification.

  12. Apparatus for growing HgI.sub.2 crystals

    DOE Patents [OSTI]

    Schieber, Michael M. (Jerusalem, IL); Beinglass, Israel (Jerusalem, IL); Dishon, Giora (Jerusalem, IL)

    1978-01-01

    A method and horizontal furnace for vapor phase growth of HgI.sub.2 crystals which utilizes controlled axial and radial airflow to maintain the desired temperature gradients. The ampoule containing the source material is rotated while axial and radial air tubes are moved in opposite directions during crystal growth to maintain a desired distance and associated temperature gradient with respect to the growing crystal, whereby the crystal interface can advance in all directions, i.e., radial and axial according to the crystallographic structure of the crystal. Crystals grown by this method are particularly applicable for use as room-temperature nuclear radiation detectors.

  13. Synthetic thermoelectric materials comprising phononic crystals

    DOE Patents [OSTI]

    El-Kady, Ihab F; Olsson, Roy H; Hopkins, Patrick; Reinke, Charles; Kim, Bongsang

    2013-08-13

    Synthetic thermoelectric materials comprising phononic crystals can simultaneously have a large Seebeck coefficient, high electrical conductivity, and low thermal conductivity. Such synthetic thermoelectric materials can enable improved thermoelectric devices, such as thermoelectric generators and coolers, with improved performance. Such synthetic thermoelectric materials and devices can be fabricated using techniques that are compatible with standard microelectronics.

  14. A STUDY OF RHIC CRYSTAL COLLIMATION.

    SciTech Connect (OSTI)

    TRBOJEVIC,D.

    1998-06-26

    The Relativistic Heavy Ion Collider (RHIC) will experience increasing longitudinal and transverse heavy ion emittances, mostly due to intra-beam scattering (IBS). The experiments in RHIC are expected to not only have reduced luminosities due to IBS but also background caused by beam halo. Primary betatron collimators will be used to remove the large amplitude particles. The efficiency of the primary collimator in RHIC strongly depends on the alignment of the jaws which needs to be within about ten micro-radians for the optimum conditions. As proposed by V. Biryukov [1] bent crystals could be used to improve the efficiency of an existing collimation system by installing them upstream of the collimator jaws. Bent crystals have been successfully used in SPS, Protvino and Fermilab for extraction of the beam particles channeled through them. This study examines possible improvements of the primary collimator system for heavy ions at RHIC by use of bent crystals. Bent crystals will reduce the collimator jaws alignment requirement and will increase collimator efficiency thereby reducing detector background.

  15. A study of RHIC crystal collimation

    SciTech Connect (OSTI)

    Trbojevic, D.; Harrison, M.; Parker, B.; Thompson, P.; Stevens, A.; Biryukov, V.; Mokhov, N.; Drozhdin, A.

    1998-08-01

    The Relativistic Heavy Ion Collider (RHIC) will experience increasing longitudinal and transverse heavy ion emittances, mostly due to intra-beam scattering (IBS). The experiments in RHIC are expected to not only have reduced luminosities due to IBS but also background caused by beam halo. Primary betatron collimators will be used to remove the large amplitude particles. The efficiency of the primary collimator in RHIC strongly depends on the alignment of the jaws which needs to be within about ten micro-radians for the optimum conditions. As proposed by V. biryukov bent crystals could be used to improve the efficiency of an existing collimation system by installing them upstream of the collimator jaws. Bent crystals have been successfully used in SPS, Protvino and Fermilab for extraction of the beam particles channeled through them. This study examines possible improvements of the primary collimator system for heavy ions at RHIC by use of bent crystals. Bent crystals will reduce the collimator jaws alignment requirement and will increase collimator efficiency thereby reducing detector background.

  16. Analytical theory of multipass crystal extraction

    SciTech Connect (OSTI)

    Biryukov, V.; Murphy, C.T.

    1997-10-01

    An analytical theory for the efficiency of particle extraction from an accelerator by means of a bent crystal is proposed. The theory agrees with all the measurements performed in the broad energy range of 14 to 900 GeV, where the efficiency range also spans over two decades, from {approximately}0.3% to {approximately}30%.

  17. City of Lake Crystal, Minnesota (Utility Company) | Open Energy...

    Open Energy Info (EERE)

    Name: City of Lake Crystal Place: Minnesota Phone Number: (605)256-6536 Website: www.ci.lake-crystal.mn.usinde Outage Hotline: (800)520-4746 References: EIA Form EIA-861 Final...

  18. Synthesis and crystal structure studies of ethyl 5-methyl-1,...

    Office of Scientific and Technical Information (OSTI)

    investigated by single crystal X-ray diffraction method. It crystallizes in monoclinic class under the space group P2sub 1c with cell parameters a 8.4593(4) , b15.6284(6)...

  19. Crystal Structure of a Protein Kinase A Complex

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

    Crystal Structure of a Protein Kinase A Complex Crystal Structure of a Protein Kinase A Complex Print Wednesday, 26 October 2005 00:00 Protein kinase A (PKA) is an enzyme that...

  20. A Spatially Resolving X-ray Crystal Spectrometer for Measurement...

    Office of Scientific and Technical Information (OSTI)

    A Spatially Resolving X-ray Crystal Spectrometer for Measurement of Ion-temperature and ... Title: A Spatially Resolving X-ray Crystal Spectrometer for Measurement of Ion-temperature ...

  1. The Biological Implications of the PP2A Crystal Structure

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

    The Biological Implications of the PP2A Crystal Structure The Biological Implications of the PP2A Crystal Structure Print Wednesday, 30 January 2008 00:00 Phosphatases, enzymes...

  2. World's largest single crystal of gold verified at Los Alamos

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

    World's largest single crystal of gold verified at Los Alamos World's largest single crystal of gold verified at Los Alamos The SCD instrument is used to determine the periodic...

  3. Crystal J. Rodarte-Romero-Engineering safer structures

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

    Crystal J. Rodarte-Romero Crystal J. Rodarte-Romero-Engineering safer structures Los Alamos bridge engineer, Rodarte-Romero is a proud steward of the historic bridge and is honored...

  4. High order reflectivity of graphite (HOPG) crystals for x ray...

    Office of Scientific and Technical Information (OSTI)

    High order reflectivity of graphite (HOPG) crystals for x ray energies up to 22 keV Citation Details In-Document Search Title: High order reflectivity of graphite (HOPG) crystals...

  5. Photo of the Week: How to Grow Superconducting Crystals | Department...

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

    grow some of the largest single-crystal high-temperature superconductors in the world. ... grow some of the largest single-crystal high-temperature superconductors in the world. ...

  6. Ytterbium- and neodymium-doped vanadate laser hose crystals having the apatite crystal structure

    DOE Patents [OSTI]

    Payne, S.A.; Kway, W.L.; DeLoach, L.D.; Krupke, W.F.; Chai, B.H.T.

    1994-08-23

    Yb[sup 3+] and Nd[sup 3+] doped Sr[sub 5](VO[sub 4])[sub 3]F crystals serve as useful infrared laser media that exhibit low thresholds of oscillation and high slope efficiencies, and can be grown with high optical quality. These laser media possess unusually high absorption and emission cross sections, which provide the crystals with the ability to generate greater gain for a given amount of pump power. Many related crystals such as Sr[sub 5](VO[sub 4])[sub 3]F crystals doped with other rare earths, transition metals, or actinides, as well as the many structural analogs of Sr[sub 5](VO[sub 4])[sub 3]F, where the Sr[sup 2+] and F[sup [minus

  7. Ytterbium- and neodymium-doped vanadate laser hose crystals having the apatite crystal structure

    DOE Patents [OSTI]

    Payne, Stephen A.; Kway, Wayne L.; DeLoach, Laura D.; Krupke, William F.; Chai, Bruce H. T.

    1994-01-01

    Yb.sup.3+ and Nd.sup.3+ doped Sr.sub.5 (VO.sub.4).sub.3 F crystals serve as useful infrared laser media that exhibit low thresholds of oscillation and high slope efficiencies, and can be grown with high optical quality. These laser media possess unusually high absorption and emission cross sections, which provide the crystals with the ability to generate greater gain for a given amount of pump power. Many related crystals such as Sr.sub.5 (VO.sub.4).sub.3 F crystals doped with other rare earths, transition metals, or actinides, as well as the many structural analogs of Sr.sub.5 (VO.sub.4).sub.3 F, where the Sr.sup.2+ and F.sup.- ions are replaced by related chemical species, have similar properties.

  8. Dynamics and pattern selection at the crystal-melt interface

    SciTech Connect (OSTI)

    Cummins, H.Z.

    1990-01-01

    This report discusses: light scattering at the crystal-melt interface; morphological instability and pattern selection; and sidebranching.

  9. Crystal nucleation and near-epitaxial growth in nacre

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

    Crystal nucleation and near-epitaxial growth in nacre Crystal nucleation and near-epitaxial growth in nacre Print Thursday, 12 December 2013 13:56 Nacre--the iridescent inner lining of many mollusk shells-- has a unique strcuture that is remarkably resistant to fracture. The nacre featured on this cover is from Haliotis laevigata with average layer thickness 470-nm. The colors represent crystal orientationthe crystal lattice tilts across tablets.left stack all tablets are yellow, hence all

  10. Imaging with Spherically Bent Crystals or Reflectors (Technical Report) |

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

    SciTech Connect Technical Report: Imaging with Spherically Bent Crystals or Reflectors Citation Details In-Document Search Title: Imaging with Spherically Bent Crystals or Reflectors This paper consists of two parts: Part I describes the working principle of a recently developed x-ray imaging crystal spectrometer, where the astigmatism of spherically bent crystals is being used with advantage to record spatially resolved spectra of highly charged ions for Doppler measurements of the

  11. Crystallization Behavior of Virgin TR-55 Silicone Rubber Measured...

    Office of Scientific and Technical Information (OSTI)

    Language: English Subject: 36 MATERIALS SCIENCE; CRYSTALLIZATION; GEOMETRY; HEATING; MELTING; NITROGEN; RUBBERS; SILICONES; STORAGE; STRAINS; THERMAL ANALYSIS; THERMAL EXPANSION; ...

  12. Growth and characterization of diammonium copper disulphate hexahydrate single crystal

    SciTech Connect (OSTI)

    Siva Sankari, R.; Perumal, Rajesh Narayana

    2014-03-01

    Graphical abstract: Diammonium copper disulphate hexahydrate (DACS) is one of the most promising inorganic dielectric crystals with exceptional mechanical properties. Good quality crystals of DACS were grown by using solution method in a period of 30 days. The grown crystals were subjected to single crystal X-ray diffraction analysis in order to establish their crystalline nature. Thermo gravimetric, differential thermal analysis, FTIR, and UVvisNIR analysis were performed for the crystal. Several solid state physical parameters have been determined for the grown crystals. The dielectric constant and the dielectric loss and AC conductivity of the grown crystal were studied as a function of frequency and temperature has been calculated and plotted. - Highlights: Diammonium copper disulphate is grown for the first time and CCDC number obtained. Thermal analysis is done to see the stability range of the crystals. Band gap and UV cut off wavelength of the crystal are determined to be 2.4 eV and 472.86 nm, respectively. Dielectric constant, dielectric loss and AC conductivity are plotted as a function of applied field. - Abstract: Diammonium copper disulphate hexahydrate is one of the most promising inorganic crystals with exceptional dielectric properties. A good quality crystal was harvested in a 30-day period using solution growth method. The grown crystal was subjected to various characterization techniques like single crystal X-ray diffraction analysis, thermo gravimetric, differential thermal analysis, FTIR, and UVvisNIR analysis. Unit cell dimensions of the grown crystal have been identified from XRD studies. Functional groups of the title compounds have been identified from FTIR studies. Thermal stability of the samples was checked by TG/DTA studies. Band gap of the crystal was calculated. The dielectric constant and dielectric loss were studied as a function of frequency of the applied field. AC conductivity was plotted as a function of temperature.

  13. Crystal growth furnace with trap doors

    DOE Patents [OSTI]

    Sachs, Emanual M. (Watertown, MA); Mackintosh, Brian H. (Lexington, MA)

    1982-06-15

    An improved furnace is provided for growing crystalline bodies from a melt. The improved furnace is characterized by a door assembly which is remotely controlled and is arranged so as to selectively shut off or permit communication between an access port in the furnace enclosure and a hot zone within that enclosure. The invention is especially adapted to facilitate use of crystal growing cartridges of the type disclosed in U.S. Pat. No. 4,118,197.

  14. Pollution Changes Clouds' Ice Crystal Genesis

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

    Pollution Changes Clouds' Ice Crystal Genesis For original submission and image(s), see ARM Research Highlights http://www.arm.gov/science/highlights/ Research Highlight Suspended high in the atmosphere, plentiful dust particles are fertile turf for growing ice. But, what are the optimal conditions for this crop? Researchers at Pacific Northwest National Laboratory (PNNL) found that miniscule particles of airborne dust, thought to be a perfect landing site for water vapor, are altered by the

  15. Method for fabricating apatite crystals and ceramics

    DOE Patents [OSTI]

    Soules, Thomas F.; Schaffers, Kathleen I.; Tassano, Jr., John B.; Hollingsworth, Joel P.

    2013-09-10

    The present invention provides a method of crystallizing Yb:C-FAP [Yb.sup.3+:Ca.sub.5(PO.sub.4).sub.3F], by dissolving the Yb:C-FAP in an acidic solution, following by neutralizing the solution. The present invention also provides a method of forming crystalline Yb:C-FAP by dissolving the component ingredients in an acidic solution, followed by forming a supersaturated solution.

  16. High energy resolution, high angular acceptance crystal monochromator

    DOE Patents [OSTI]

    Alp, Ercan E. (Bolingbrook, IL); Mooney, Timothy M. (Westmont, IL); Toellner, Thomas (Green Bay, WI)

    1996-06-04

    A 4-bounce dispersive crystal monochromator reduces the bandpass of synchrotron radiation to a 10-50 meV range without sacrificing angular acceptance. The monochromator includes the combination of an asymmetrical channel-cut single crystal of lower order reflection and a symmetrical channel-cut single crystal of higher order reflection in a nested geometric configuration. In the disclosed embodiment, a highly asymmetrically cut (.alpha.=20) outer silicon crystal (4 2 2) with low order reflection is combined with a symmetrically cut inner silicon crystal (10 6 4) with high order reflection to condition a hard x-ray component (5-30 keV) of synchrotron radiation down to the .mu.eV-neV level. Each of the crystals is coupled to the combination of a positioning inchworm and angle encoder via a respective rotation stage for accurate relative positioning of the crystals and precise energy tuning of the monochromator.

  17. High energy resolution, high angular acceptance crystal monochromator

    DOE Patents [OSTI]

    Alp, E.E.; Mooney, T.M.; Toellner, T.

    1996-06-04

    A 4-bounce dispersive crystal monochromator reduces the bandpass of synchrotron radiation to a 10-50 meV range without sacrificing angular acceptance. The monochromator includes the combination of an asymmetrical channel-cut single crystal of lower order reflection and a symmetrical channel-cut single crystal of higher order reflection in a nested geometric configuration. In the disclosed embodiment, a highly asymmetrically cut ({alpha}=20) outer silicon crystal (4 2 2) with low order reflection is combined with a symmetrically cut inner silicon crystal (10 6 4) with high order reflection to condition a hard x-ray component (5--30 keV) of synchrotron radiation down to the {micro}eV-neV level. Each of the crystals is coupled to the combination of a positioning inchworm and angle encoder via a respective rotation stage for accurate relative positioning of the crystals and precise energy tuning of the monochromator. 7 figs.

  18. Optical trapping apparatus, methods and applications using photonic crystal resonators

    DOE Patents [OSTI]

    Erickson, David; Chen, Yih-Fan

    2015-06-16

    A plurality of photonic crystal resonator optical trapping apparatuses and a plurality optical trapping methods using the plurality of photonic crystal resonator optical trapping apparatuses include located and formed over a substrate a photonic waveguide that is coupled (i.e., either separately coupled or integrally coupled) with a photonic crystal resonator. In a particular embodiment, the photonic waveguide and the photonic crystal resonator comprise a monocrystalline silicon (or other) photonic material absent any chemical functionalization. In another particular embodiment, the photonic waveguide and the photonic crystal resonator comprise a silicon nitride material which when actuating the photonic crystal resonator optical trapping apparatus with a 1064 nanometer resonant photonic radiation wavelength (or other resonant photonic radiation wavelength in a range from about 700 to about 1200 nanometers) provides no appreciable heating of an aqueous sample fluid that is analyzed by the photonic crystal resonator optical trapping apparatus.

  19. Development of Uranium Crystallization System in 'NEXT' Reprocessing Process

    SciTech Connect (OSTI)

    Ohyama, Koichi; Nomura, Kazunori; Washiya, Tadahiro; Tayama, Toshimitu; Yano, Kimihiko; Shibata, Atsuhiro; Komaki, Jun; Chikazawa, Takahiro; Kikuchi, Toshiaki

    2007-07-01

    Japan Atomic Energy Agency (JAEA) has been developing the crystallization process technology in cooperation with Mitsubishi Materials Corporation, Saitama University and Waseda University. We have carried out experimental studies with uranium, MOX and spent fuel dissolved solution, and flowsheet analysis was researched. Crystal refinement study has been started to get more purified crystal. In association with these studies, an innovative continuous crystallizer and its system was developed to ensure high process performance. From the design study, an annular type continuous crystallizer was selected as the most promising design, and performance was confirmed by small-scale test and engineering scale demonstration at uranium crystallization conditions. In this paper, the research and development of crystallization process are described. (authors)

  20. Low Radioactivity Crystals for Neutrinoless Double Beta Decay Detectors

    SciTech Connect (OSTI)

    Dafinei, Ioan [Sezione INFN di Roma, P-le Aldo Moro 2, Roma I-00185 (Italy)

    2011-04-27

    The production of crystals needed for rare events physics represent a relatively new, exciting challenge in the field of materials science and engineering. Extremely low concentration of radioactive impurities and very high crystal perfection is required for the crystals to be used in experiments in which the main concerns are the reduction of the background and the use of high sensitivity detectors. A further complication is the fact that for an experiment with a significant discovery potential, relatively large quantities of crystals are needed. The present work makes a review of the general problems related to the production of crystals for rare events physics and gives details related to the production of the TeO{sub 2} crystals needed for the major experiment in this field using bolometric technique, namely the CUORE experiment. The potential use of crystals for future double beta decay experiments is also discussed.

  1. Influence of Substrate on Crystallization in Polythiophene/fullerene Blends

    SciTech Connect (OSTI)

    C He; D Germack; J Kline; D Delongchamp; D Fischer; C Snyder; M Toney; J Kushmerick; L Richter

    2011-12-31

    The nanoscale morphology of the active layer in organic, bulk heterojunction (BHJ) solar cells is crucial to device performance. Often a combination of casting conditions and post deposition thermal treatment is used to optimize the morphology. In general, the development of microscopic crystals is deleterious, as the exciton diffusion length is {approx}10 nm. We find that the microscopic crystallization behavior in polythiophene/fullerene blends is strongly influenced by the substrate on which the BHJ is cast. With a silicon oxide substrate, the crystal nucleation density is high and significant crystallization occurs at a temperature of 140 C. On more hydrophobic substrates, significantly higher temperatures are required for observable crystallization. This difference is attributed to the interfacial segregation of the PCBM, controlled by the substrate surface energy. The substrate dependence of crystallization has significant implications on the fullerene crystal growth mechanisms and practical implications for device studies.

  2. Photonic Crystals for Enhancing Thermophotovoltaic Energy Conversion

    SciTech Connect (OSTI)

    LIN, SHAWN-YU; FLEMING, JAMES G.; MORENO, JOSEPH A.

    2003-03-01

    Thermophotovoltaics (TPV) converts the radiant energy of a thermal source into electrical energy using photovoltaic cells. TPV has a number of attractive features, including: fuel versatility (nuclear, fossil, solar, etc.), quiet operation, low maintenance, low emissions, light weight, high power density, modularity, and possibility for cogeneration of heat and electricity. Some of these features are highly attractive for military applications (Navy and Army). TPV could also be used for distributed power and automotive applications wherever fuel cells, microturbines, or cogeneration are presently being considered if the efficiencies could be raised to around 30%. This proposal primarily examine approaches to improving the radiative efficiency. The ideal irradiance for the PV cell is monochromatic illumination at the bandgap. The photonic crystal approach allows for the tailoring of thermal emission spectral bandwidth at specific wavelengths of interest. The experimental realization of metallic photonic crystal structures, the optical transmission, reflection and absorption characterization of it have all been carried out in detail and will be presented next. Additionally, comprehensive models of TPV conversion has been developed and applied to the metallic photonic crystal system.

  3. New organic crystals for pulse shape discrimination

    SciTech Connect (OSTI)

    Hull, G; Zaitseva, N; Cherepy, N; Newby, J; Stoeffl, W; Payne, S

    2008-07-16

    Efficient, readily-available, low-cost, high-energy neutron detectors can play a central role in detecting illicit nuclear weapons since neutrons are a strong indication for the presence of fissile material such as Plutonium and Highly-Enriched Uranium. The main challenge in detecting fast neutrons consists in the discrimination of the signal from the gamma radiation background. At present, the only well-investigated organic crystal scintillator for fast neutron detection, in a n/{gamma} mixed field, is stilbene, which while offering good pulse shape discrimination, is not widely used because of its limited availability and high cost. In this work we report the results of our studies made with a number of new organic crystals, which exhibit pulse shape discrimination for detection of fast neutrons. In particular 1,1,4,4-tetraphenyl-1,3-butadiene features a light yield higher than anthracene and a Figure of Merit (FOM) for the pulse shape discrimination better than stilbene. New crystals are good candidates for the low-cost solution growth method, thus representing promising organic scintillators for widespread deployment for high-energy neutron detection.

  4. Photochemical switching behavior of azofunctionalized polymer liquid crystal/SiO{sub 2} composite photonic crystal

    SciTech Connect (OSTI)

    Moritsugu, M.; Kim, S. N.; Ogata, T.; Nonaka, T.; Kurihara, S.; Kubo, S.; Segawa, H.; Sato, O.

    2006-10-09

    A photochemically tunable photonic crystal was prepared by infiltrating azopolymer liquid crystal in a SiO{sub 2} inverse opal structure. The SiO{sub 2} inverse opal film obtained reflected a light corresponding to the periodicity as well as the refractive indices of the inverse opal structure. Linearly polarized light irradiation shifted the reflection band to longer wavelength more than 15 nm. This is caused by the formation of anisotropic molecular orientation of the azopolymer. The switched state was stable in the dark, and the reversible switching of the reflection band can be achieved by the linearly and circularly polarized light irradiations.

  5. Crystallization and collapse in relativistically degenerate matter

    SciTech Connect (OSTI)

    Akbari-Moghanjoughi, M.

    2013-04-15

    In this paper, it is shown that a mass density limit exists beyond which the relativistically degenerate matter would crystallize. The mass density limit, found here, is quite analogous to the mass limit predicted by Chandrasekhar for a type of compact stars called white dwarfs (M{sub Ch} Asymptotically-Equal-To 1.43 Solar Mass). In this study, the old problem of white dwarf core collapse, which has been previously investigated by Chandrasekhar using hydrostatic stability criteria, is revisited in the framework of the quantum hydrodynamics model by inspection of the charge screening at atomic scales in the relativistic degeneracy plasma regime taking into account the relativistic Fermi-Dirac statistics and electron interaction features such as the quantum statistical pressure, Coulomb attraction, electron exchange-correlation, and quantum recoil effects. It is revealed that the existence of ion correlation and crystallization of matter in the relativistically degenerate plasma puts a critical mass density limit on white dwarf core region. It is shown that a white dwarf star with a core mass density beyond this critical limit can undergo the spontaneous core collapse (SCC). The SCC phenomenon, which is dominantly caused by the electron quantum recoil effect (interference and localization of the electron wave function), leads to a new exotic state of matter. In such exotic state, the relativistic electron degeneracy can lead the white dwarf crystallized core to undergo the nuclear fusion and an ultimate supernova by means of the volume reduction (due to the enhanced compressibility) and huge energy release (due to the increase in cohesive energy), under the stars huge inward gravitational pressure. Moreover, it is found that the SCC phenomenon is significantly affected by the core composition (it is more probable for heavier plasmas). The critical mass density found here is consistent with the values calculated for core density of typical white dwarf stars.

  6. Growth of large zeolite crystals in space

    SciTech Connect (OSTI)

    Sacco, A. Jr.; Dixon, A.; Thompson, R.; Scott, G.; Ditr, J.

    1988-01-01

    Synthesis studies performed using close analogs of triethanolamine (TEA) have shown that all three hydroxyl groups and the amine group in this molecule are necessary to provide nucleation suppression. Studies using C-13 nuclear magnetic resonance (NMR) revealed that the hydroxyl ions and the amine group are involved in the formation of an aluminum complex. It was also shown that silicate species do not interact this way with TEA in an alkaline solution. These results suggest that successful aluminum complexation leads to nucleation in zeolite-A crystallization.

  7. Super-collimation by axisymmetric photonic crystals

    SciTech Connect (OSTI)

    Purlys, V.; Gailevi?ius, D.; Peckus, M.; Gadonas, R.; Maigyte, L.; Staliunas, K.

    2014-06-02

    We propose and experimentally show the mechanism of beam super-collimation by axisymmetric photonic crystals, specifically by periodic (in propagation direction) structure of layers of concentric rings. The physical mechanism behind the effect is an inverse scattering cascade of diffracted wave components back into on- and near-axis angular field components, resulting in substantial enhancement of intensity of these components. We explore the super-collimation by numerical calculations and prove it experimentally. We demonstrate experimentally the axial field enhancement up to 7 times in terms of field intensity.

  8. Plasmonic crystal enhanced refractive index sensing

    SciTech Connect (OSTI)

    Stein, Benedikt; Devaux, Eloïse; Genet, Cyriaque Ebbesen, Thomas W.

    2014-06-23

    We demonstrate experimentally how the local anisotropy of the dispersion relation of surface plasmon modes propagating over periodic metal gratings can lead to an enhancement of the figure of merit of refractive index sensors. Exploiting the possibility to acquire defocused images of the Fourier space of a highly stable leakage radiation microscope, we report a twofold increase in sensing sensitivity close to the band gap of a one-dimensional plasmonic crystal where the anisotropy of the band structure is the most important. A practical sensing resolution of O(10{sup −6}) refractive index units is demonstrated.

  9. Platinum Nanoclusters Out-Perform Single Crystals

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

    Platinum Nanoclusters Out-Perform Single Crystals Print When it comes to metal catalysts, platinum is the standard. However, at about $2,000 an ounce, the high cost of the raw material presents major challenges for the future wide-scale use of platinum in fuel cells. Berkeley Lab research suggests that one possible way to meet these challenges is to think small. Researchers from Berkeley Lab's Materials Sciences Division have found that under high pressure-comparable to the pressures at which

  10. Platinum Nanoclusters Out-Perform Single Crystals

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

    Platinum Nanoclusters Out-Perform Single Crystals Print When it comes to metal catalysts, platinum is the standard. However, at about $2,000 an ounce, the high cost of the raw material presents major challenges for the future wide-scale use of platinum in fuel cells. Berkeley Lab research suggests that one possible way to meet these challenges is to think small. Researchers from Berkeley Lab's Materials Sciences Division have found that under high pressure-comparable to the pressures at which

  11. Platinum Nanoclusters Out-Perform Single Crystals

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

    Platinum Nanoclusters Out-Perform Single Crystals Print When it comes to metal catalysts, platinum is the standard. However, at about $2,000 an ounce, the high cost of the raw material presents major challenges for the future wide-scale use of platinum in fuel cells. Berkeley Lab research suggests that one possible way to meet these challenges is to think small. Researchers from Berkeley Lab's Materials Sciences Division have found that under high pressure-comparable to the pressures at which

  12. Platinum Nanoclusters Out-Perform Single Crystals

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

    Platinum Nanoclusters Out-Perform Single Crystals Print When it comes to metal catalysts, platinum is the standard. However, at about $2,000 an ounce, the high cost of the raw material presents major challenges for the future wide-scale use of platinum in fuel cells. Berkeley Lab research suggests that one possible way to meet these challenges is to think small. Researchers from Berkeley Lab's Materials Sciences Division have found that under high pressure-comparable to the pressures at which

  13. Platinum Nanoclusters Out-Perform Single Crystals

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

    Platinum Nanoclusters Out-Perform Single Crystals Print When it comes to metal catalysts, platinum is the standard. However, at about $2,000 an ounce, the high cost of the raw material presents major challenges for the future wide-scale use of platinum in fuel cells. Berkeley Lab research suggests that one possible way to meet these challenges is to think small. Researchers from Berkeley Lab's Materials Sciences Division have found that under high pressure-comparable to the pressures at which

  14. Platinum Nanoclusters Out-Perform Single Crystals

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

    Platinum Nanoclusters Out-Perform Single Crystals Print When it comes to metal catalysts, platinum is the standard. However, at about $2,000 an ounce, the high cost of the raw material presents major challenges for the future wide-scale use of platinum in fuel cells. Berkeley Lab research suggests that one possible way to meet these challenges is to think small. Researchers from Berkeley Lab's Materials Sciences Division have found that under high pressure-comparable to the pressures at which

  15. Platinum Nanoclusters Out-Perform Single Crystals

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

    Platinum Nanoclusters Out-Perform Single Crystals Print When it comes to metal catalysts, platinum is the standard. However, at about $2,000 an ounce, the high cost of the raw material presents major challenges for the future wide-scale use of platinum in fuel cells. Berkeley Lab research suggests that one possible way to meet these challenges is to think small. Researchers from Berkeley Lab's Materials Sciences Division have found that under high pressure-comparable to the pressures at which

  16. Crystallization of M-CSF.alpha.

    DOE Patents [OSTI]

    Pandit, Jayvardhan (Mystic, CT); Jancarik, Jarmila (Walnut Creek, CA); Kim, Sung-Hou (Moraga, CA); Koths, Kirston (El Cerrito, CA); Halenbeck, Robert (San Rafael, CA); Fear, Anna Lisa (Oakland, CA); Taylor, Eric (Oakland, CA); Yamamoto, Ralph (Martinez, CA); Bohm, Andrew (Berkeley, CA)

    1999-01-01

    The present invention is directed to methods for crystallizing macrophage colony stimulating factor (M-CSF) and to a crystalline M-CSF produced thereby. The present invention is also directed to methods for designing and producing M-CSF agonists and antagonists using information derived from the crystallographic structure of M-CSF. The invention is also directed to methods for screening M-CSF agonists and antagonists. In addition, the present invention is directed to an isolated, purified, soluble and functional M-CSF receptor.

  17. Platinum Nanoclusters Out-Perform Single Crystals

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

    Platinum Nanoclusters Out-Perform Single Crystals Print When it comes to metal catalysts, platinum is the standard. However, at about $2,000 an ounce, the high cost of the raw material presents major challenges for the future wide-scale use of platinum in fuel cells. Berkeley Lab research suggests that one possible way to meet these challenges is to think small. Researchers from Berkeley Lab's Materials Sciences Division have found that under high pressure-comparable to the pressures at which

  18. Platinum Nanoclusters Out-Perform Single Crystals

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

    Platinum Nanoclusters Out-Perform Single Crystals Print When it comes to metal catalysts, platinum is the standard. However, at about $2,000 an ounce, the high cost of the raw material presents major challenges for the future wide-scale use of platinum in fuel cells. Berkeley Lab research suggests that one possible way to meet these challenges is to think small. Researchers from Berkeley Lab's Materials Sciences Division have found that under high pressure-comparable to the pressures at which

  19. Platinum Nanoclusters Out-Perform Single Crystals

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

    Platinum Nanoclusters Out-Perform Single Crystals Print When it comes to metal catalysts, platinum is the standard. However, at about $2,000 an ounce, the high cost of the raw material presents major challenges for the future wide-scale use of platinum in fuel cells. Berkeley Lab research suggests that one possible way to meet these challenges is to think small. Researchers from Berkeley Lab's Materials Sciences Division have found that under high pressure-comparable to the pressures at which

  20. Platinum Nanoclusters Out-Perform Single Crystals

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

    Platinum Nanoclusters Out-Perform Single Crystals Print When it comes to metal catalysts, platinum is the standard. However, at about $2,000 an ounce, the high cost of the raw material presents major challenges for the future wide-scale use of platinum in fuel cells. Berkeley Lab research suggests that one possible way to meet these challenges is to think small. Researchers from Berkeley Lab's Materials Sciences Division have found that under high pressure-comparable to the pressures at which

  1. Models of crystallization in evaporating droplets

    SciTech Connect (OSTI)

    Ford, I.J.

    1996-12-31

    The spray drying of a droplet containing a substance in solution can produce solid particles with a variety of final shapes: hollow, punctured, squashed, as well as solid spheres. The geometry affects the properties of the product. Models are presented here which describe the processes of solvent evaporation and solute crystallization as drying takes place. The formation of a crust on the surface of the droplet is addressed. It is proposed that such a crust with a thickness of two crystallite diameters can develop into dry hollow shell. Some example calculations of the spray drying of droplets of sodium chloride solution are described.

  2. Oxidation and crystal field effects in uranium

    SciTech Connect (OSTI)

    Tobin, J. G.; Booth, C. H.; Shuh, D. K.; van der Laan, G.; Sokaras, D.; Weng, T. -C.; Yu, S. W.; Bagus, P. S.; Tyliszczak, T.; Nordlund, D.

    2015-07-06

    An extensive investigation of oxidation in uranium has been pursued. This includes the utilization of soft x-ray absorption spectroscopy, hard x-ray absorption near-edge structure, resonant (hard) x-ray emission spectroscopy, cluster calculations, and a branching ratio analysis founded on atomic theory. The samples utilized were uranium dioxide (UO2), uranium trioxide (UO3), and uranium tetrafluoride (UF4). As a result, a discussion of the role of non-spherical perturbations, i.e., crystal or ligand field effects, will be presented.

  3. Manipulation of Phonons with Phononic Crystals

    SciTech Connect (OSTI)

    Leseman, Zayd Chad

    2015-07-09

    There were three research goals associated with this project. First, was to experimentally demonstrate phonon spectrum control at THz frequencies using Phononic Crystals (PnCs), i.e. demonstrate coherent phonon scattering with PnCs. Second, was to experimentally demonstrate analog PnC circuitry components at GHz frequencies. The final research goal was to gain a fundamental understanding of phonon interaction using computational methods. As a result of this work, 7 journal papers have been published, 1 patent awarded, 14 conference presentations given, 4 conference publications, and 2 poster presentations given.

  4. Non-linear optical crystal vibration sensing device

    DOE Patents [OSTI]

    Kalibjian, R.

    1994-08-09

    A non-linear optical crystal vibration sensing device including a photorefractive crystal and a laser is disclosed. The laser produces a coherent light beam which is split by a beam splitter into a first laser beam and a second laser beam. After passing through the crystal the first laser beam is counter-propagated back upon itself by a retro-mirror, creating a third laser beam. The laser beams are modulated, due to the mixing effect within the crystal by vibration of the crystal. In the third laser beam, modulation is stable and such modulation is converted by a photodetector into a usable electrical output, intensity modulated in accordance with vibration applied to the crystal. 3 figs.

  5. Ytterbium-doped borate fluoride laser crystals and lasers

    DOE Patents [OSTI]

    Schaffers, Kathleen I.; DeLoach, Laura D.; Payne, Stephen A.; Keszler, Douglas A.

    1997-01-01

    A new class of solid state laser crystals and lasers are formed from Yb-doped borate fluoride host crystals. The general formula for the host crystals is MM'(BO.sub.3)F, where M, M' are monovalent, divalent aria trivalent metal cations. A particular embodiment of the invention is Yb-doped BaCaBO.sub.3 F (Yb:BCBF). BCBF and some of the related derivative crystals are capable of nonlinear frequency conversion, whereby the fundamental of the laser is converted to a longer or shorter wavelength. In this way, these new crystals can simultaneously serve as self-frequency doubling crystals and laser materials within the laser resonator.

  6. Sagittal focusing of synchrotron x radiation with curved crystals

    SciTech Connect (OSTI)

    Sparks, C.J. Jr.; Ice, G.E.; Wong, J.; Batterman, B.W.

    1981-01-01

    We describe the sagittal focusing of x rays with singly bent crystals that accept the meridian plane divergence from a similar but flat crystal to form a pair in a nondispersive two-crystal Bragg monochromator. Curved crystals can intercept from 5 to 20 times the sagittal divergence of curved mirrors at x-ray energies above 10 keV. Anticlastic (transverse) bending of the crystal is made negligible in the meridian plane with reinforcing ribs cut parallel to the plane of scattering. Results show that at energies of 10, 20, and 30 keV the bent crystal performs efficiently and images the source size at the Cornell High Energy Synchrotron Source.

  7. Non-linear optical crystal vibration sensing device

    DOE Patents [OSTI]

    Kalibjian, Ralph (Livermore, CA)

    1994-01-11

    A non-linear optical crystal vibration sensing device (10) including a photorefractive crystal (26) and a laser (12). The laser (12 ) produces a coherent light beam (14) which is split by a beam splitter (18) into a first laser beam (20) and a second laser beam (22). After passing through the crystal (26) the first laser beam (20) is counter-propagated back upon itself by a retro-mirror (32), creating a third laser beam (30). The laser beams (20, 22, 30) are modulated, due to the mixing effect within the crystal (26) by vibration of the crystal (30). In the third laser beam (30), modulation is stable and such modulation is converted by a photodetector (34) into a usable electrical output, intensity modulated in accordance with vibration applied to the crystal (26).

  8. Photonic crystal devices formed by a charged-particle beam

    DOE Patents [OSTI]

    Lin, Shawn-Yu (Albuquerque, NM); Koops, Hans W. P. (Ober-Ramstadt, DE)

    2000-01-01

    A photonic crystal device and method. The photonic crystal device comprises a substrate with at least one photonic crystal formed thereon by a charged-particle beam deposition method. Each photonic crystal comprises a plurality of spaced elements having a composition different from the substrate, and may further include one or more impurity elements substituted for spaced elements. Embodiments of the present invention may be provided as electromagnetic wave filters, polarizers, resonators, sources, mirrors, beam directors and antennas for use at wavelengths in the range from about 0.2 to 200 microns or longer. Additionally, photonic crystal devices may be provided with one or more electromagnetic waveguides adjacent to a photonic crystal for forming integrated electromagnetic circuits for use at optical, infrared, or millimeter-wave frequencies.

  9. Ytterbium-doped borate fluoride laser crystals and lasers

    DOE Patents [OSTI]

    Schaffers, K.I.; DeLoach, L.D.; Payne, S.A.; Keszler, D.A.

    1997-10-14

    A new class of solid state laser crystals and lasers are formed from Yb-doped borate fluoride host crystals. The general formula for the host crystals is MM{prime}(BO{sub 3})F, where M, M{prime} are monovalent, divalent aria trivalent metal cations. A particular embodiment of the invention is Yb-doped BaCaBO{sub 3}F (Yb:BCBF). BCBF and some of the related derivative crystals are capable of nonlinear frequency conversion, whereby the fundamental of the laser is converted to a longer or shorter wavelength. In this way, these new crystals can simultaneously serve as self-frequency doubling crystals and laser materials within the laser resonator. 6 figs.

  10. Perpendicular Magnetism Unparalleled Find in Single Crystal | The Ames

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

    Laboratory Perpendicular Magnetism Unparalleled Find in Single Crystal Two distinct types of magnetism aligned perpendicular in a single crystal have been detailed in new measurements on single-crystal and powered samples composed of barium, potassium, manganese, and arsenic. Antiferromagnetism occurs with a checkerboard-style patterning of the total atomic magnetic moments due to the spins of the localized electrons of the manganese atoms (known as 'local-moment magnetism'). Aligning

  11. Variable-metric diffraction crystals for x-ray optics

    SciTech Connect (OSTI)

    Smither, R.K.; Fernandez, P.B. )

    1992-02-01

    A variable-metric (VM) crystal is one in which the spacing between the crystalline planes changes with position in the crystal. This variation can be either parallel to the crystalline planes or perpendicular to the crystalline planes of interest and can be produced by either introducing a thermal gradient in the crystal or by growing a crystal made of two or more elements and changing the relative percentages of the two elements as the crystal is grown. A series of experiments were performed in the laboratory to demonstrate the principle of the variable-metric crystal and its potential use in synchrotron beam lines. One of the most useful applications of the VM crystal is to increase the number of photons per unit bandwidth in a diffracted beam without losing any of the overall intensity. In a normal synchrotron beam line that uses a two-crystal monochromator, the bandwidth of the diffracted photon beam is determined by the vertical opening angle of the beam which is typically 0.10--0.30 mrad or 20--60 arcsec. When the VM crystal approach is applied, the bandwidth of the beam can be made as narrow as the rocking curve of the diffracting crystal, which is typically 0.005--0.050 mrad or 1--10 arcsec. Thus a very large increase of photons per unit bandwidth (or per unit energy) can be achieved through the use of VM crystals. When the VM principle is used with bent crystals, new kinds of x-ray optical elements can be generated that can focus and defocus x-ray beams much like simple lenses where the focal length of the lens can be changed to match its application. Thus both large magnifications and large demagnifications can be achieved as well as parallel beams with narrow bandwidths.

  12. Method for surface treatment of a cadmium zinc telluride crystal

    DOE Patents [OSTI]

    James, Ralph; Burger, Arnold; Chen, Kuo-Tong; Chang, Henry

    1999-01-01

    A method for treatment of the surface of a CdZnTe (CZT) crystal that reduces surface roughness (increases surface planarity) and provides an oxide coating to reduce surface leakage currents and thereby, improve resolution. A two step process is disclosed, etching the surface of a CZT crystal with a solution of lactic acid and bromine in ethylene glycol, following the conventional bromine/methanol etch treatment, and after attachment of electrical contacts, oxidizing the CZT crystal surface.

  13. Method for surface treatment of a cadmium zinc telluride crystal

    DOE Patents [OSTI]

    James, R.; Burger, A.; Chen, K.T.; Chang, H.

    1999-08-03

    A method for treatment of the surface of a CdZnTe (CZT) crystal is disclosed that reduces surface roughness (increases surface planarity) and provides an oxide coating to reduce surface leakage currents and thereby, improve resolution. A two step process is disclosed, etching the surface of a CZT crystal with a solution of lactic acid and bromine in ethylene glycol, following the conventional bromine/methanol etch treatment, and after attachment of electrical contacts, oxidizing the CZT crystal surface. 3 figs.

  14. Application of channeling in bent crystals to charged particle beams

    Office of Scientific and Technical Information (OSTI)

    (Conference) | SciTech Connect Application of channeling in bent crystals to charged particle beams Citation Details In-Document Search Title: Application of channeling in bent crystals to charged particle beams The process of channeling of charged particle beams in bent crystals is described, including the effects of angular acceptance, spatial acceptance, normal dechanneling, bending dechanneling, and surface acceptance. Some bending applications that have been tried and future

  15. Lyotropic Liquid Crystal (LLC) Nanofiltration Membranes - Energy Innovation

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

    Portal Biomass and Biofuels Biomass and Biofuels Advanced Materials Advanced Materials Find More Like This Return to Search Lyotropic Liquid Crystal (LLC) Nanofiltration Membranes Applications in biofuels and bio-process mixture separations University of Colorado Contact CU About This Technology Publications: PDF Document Publication CU2412B (Advanced LLC Membranes) Marketing Summary.pdf (154 KB) Lyotropic Liquid Crystal (LLC) Nanofiltration Membranes Lyotropic Liquid Crystal (LLC)

  16. A double crystal monochromator using tangentially bend crystals in combination with toroidal mirror focusing

    SciTech Connect (OSTI)

    Feng, Jun, Thompson,A.C.; Padmore,H.A.

    2000-02-24

    In collaboration with the Chemistry Department at the University of California at Berkeley, the ALS is building a beamline for structural determination in materials chemistry. The system will be used for single crystal x-ray diffraction on crystals that are too small or disordered for examination on laboratory systems, and typically will be used for crystals in the 5 - 20 micron regime. As some of the materials being designed are of the size of small proteins, phasing using direct methods is problematic, and so use of multiple wavelength anomalous dispersion techniques will be employed in many cases. The production of new compounds has been revolutionized in recent years with the development of combinatorial synthesis techniques, and a major b2048 to further advances in this field is access to rapid measurement of structural parameters. The specification of the beamline follows from these points. It must have a small focal spot to match closely the size of the crystals, high resolution for MAD techniques, and a high flux in the small focus. The strategy for satisfying these constraints is to us a system which is compact and which uses the minimum number of components. This is done in this case by using a pseudo channel cut crystal monochromator with tangentially bent crystals, in combination with a 1:1 focusing toroidal mirror. The toroidal mirror at 1:1 magnification has only very small aberrations, and from a 220 (h) by 25 (v) [micro] m FWHM source, an image of 220 by 45 [micro]m FWHM should be produced for a 3 mrad horizontal aperture for a full vertical aperture. This has already been achieved on an existing beamline. The crystal monochromator uses tangentially bent crystals in a concave - convex configuration to achieve matching of Bragg angles to the divergent source, while maintaining zero focusing power. A useful feature of this arrangement is that while there is an optimum crystal curvature for each energy that gives the expected Darwin width limited resolution, fixing the curvature gives approximately ideal resolution over typically 2 keV for the ALS bending magnet source. A further simplification is that the whole optical system will be inside the shield wall, with only a small pipe emerging from the shield wall to feed a standard commercial diffraction system. This means that the mirror will be at only 6.5 m from the source. This means that the toroidal mirror can be as short as 300 mm while collecting most of the vertical radiation fan. In addition, as the required tangential slope error is related to the angular size of the source, putting the mirror close reduces the slope error requirements substantially. These aspects together should result in a simple, low cost and very high performance system for small crystal, small molecule cr2048llography.

  17. Diffraction crystal for sagittally focusing x-rays

    DOE Patents [OSTI]

    Ice, Gene E. (Oak Ridge, TN); Sparks, Jr., Cullie J. (Oak Ridge, TN)

    1984-01-01

    The invention is a new type of diffraction crystal designed for sagittally focusing photons of various energies. The invention is based on the discovery that such focusing is not obtainable with conventional crystals because of distortion resulting from anticlastic curvature. The new crystal comprises a monocrystalline base having a front face contoured for sagittally focusing photons and a back face provided with rigid, upstanding, stiffening ribs restricting anticlastic curvature. When mounted in a suitable bending device, the reflecting face of the crystal can be adjusted to focus photons having any one of a range of energies.

  18. Method for the preparation of photochromic insulating crystals

    DOE Patents [OSTI]

    Abraham, Marvin M.; Boldu, Jose L.; Chen, Yok; Orera, Victor M.

    1986-01-01

    A method for preparing reversible-photochromic magnesium oxide (MgO) crystals. Single crystals of MgO doped with both lithium (Li) and nickel (Ni) are grown by a conventional arc fusion method. The as-grown crystals are characterized by an amber coloration. The crystals lose the amber coloration and become photochromic when they are thermochemically reduced by heating at temperatures greater than 1000.degree. K. in a hydrogen atmosphere. Alternate irradiation with UV and visible light result in rejuvenation and bleaching of the amber coloration, respectively.

  19. Crystal structure of elongation factor 4 bound to a clockwise...

    Office of Scientific and Technical Information (OSTI)

    Search Title: Crystal structure of elongation factor 4 bound to a clockwise ratcheted ribosome Authors: Gagnon, Matthieu G. ; Lin, Jinzhong ; Bulkley, David ; Steitz, Thomas A. ...

  20. Identifying, studying and making good use of macromolecular crystals

    SciTech Connect (OSTI)

    Calero, Guillermo; Cohen, Aina E.; Luft, Joseph R.; Newman, Janet; Snell, Edward H.

    2014-07-25

    As technology advances, the crystal volume that can be used to collect useful X-ray diffraction data decreases. The technologies available to detect and study growing crystals beyond the optical resolution limit and methods to successfully place the crystal into the X-ray beam are discussed. Structural biology has contributed tremendous knowledge to the understanding of life on the molecular scale. The Protein Data Bank, a depository of this structural knowledge, currently contains over 100 000 protein structures, with the majority stemming from X-ray crystallography. As the name might suggest, crystallography requires crystals. As detectors become more sensitive and X-ray sources more intense, the notion of a crystal is gradually changing from one large enough to embellish expensive jewellery to objects that have external dimensions of the order of the wavelength of visible light. Identifying these crystals is a prerequisite to their study. This paper discusses developments in identifying these crystals during crystallization screening and distinguishing them from other potential outcomes. The practical aspects of ensuring that once a crystal is identified it can then be positioned in the X-ray beam for data collection are also addressed.

  1. Spectroscopic, thermal and structural studies on manganous malate crystals

    SciTech Connect (OSTI)

    Thomas, J. Lincy, A. Mahalakshmi, V.; Saban, K. V.

    2013-01-15

    Prismatic crystals of manganous malate have been prepared by controlled ionic diffusion in hydrosilica gel. The structure was elucidated using single crystal X-ray diffraction. The crystals are orthorhombic with space group Pbca. Vibrations of the functional groups were identified by the FTIR spectrum. Thermogravimetric and differential thermal analyses (TG-DTA) were carried out to explore the thermal decomposition pattern of the material. Structural information derived from FTIR and TG-DTA studies is in conformity with the single crystal XRD data.

  2. Temperature-insensitive phase-matched optical harmonic conversion crystal

    DOE Patents [OSTI]

    Barker, Charles E. (Sunnyvale, CA); Eimerl, David (Livermore, CA); Velsko, Stephan P. (Livermore, CA); Roberts, David (Sagamore Hills, OH)

    1993-01-01

    Temperature-insensitive, phase-matched harmomic frequency conversion of laser light at a preferred wavelength of 1.064 microns can be achieved by use of a crystal of deuterated l-arginine phosphate. The crystal is cut and oriented so that the laser light propagates inside the crystal along one of several required directions, which correspond to a temperature-insensitive, phase-matching locus. The method of measuring and calculating the temperature-insensitive, phase-matching angles can be extended to other fundamental wavelengths and other crystal compositions.

  3. The crystal structure of choline kinase reveals a eukaryotic...

    Office of Scientific and Technical Information (OSTI)

    reveals a eukaryotic protein kinase fold Citation Details In-Document Search Title: The crystal structure of choline kinase reveals a eukaryotic protein kinase fold Choline ...

  4. Crystallization and preliminary X-ray crystallographic studies...

    Office of Scientific and Technical Information (OSTI)

    protein from Drosophila melanogaster Citation Details In-Document Search Title: Crystallization and preliminary X-ray crystallographic studies of Drep-3, a DFF-related protein ...

  5. Temperature-insensitive phase-matched optical harmonic conversion crystal

    DOE Patents [OSTI]

    Barker, C.E.; Eimerl, D.; Velsko, S.P.; Roberts, D.

    1993-11-23

    Temperature-insensitive, phase-matched harmonic frequency conversion of laser light at a preferred wavelength of 1.064 microns can be achieved by use of a crystal of deuterated l-arginine phosphate. The crystal is cut and oriented so that the laser light propagates inside the crystal along one of several required directions, which correspond to a temperature-insensitive, phase-matching locus. The method of measuring and calculating the temperature-insensitive, phase-matching angles can be extended to other fundamental wavelengths and other crystal compositions. 12 figures.

  6. Single Particle Database of Natural Ice Crystals: Dimensions

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

    Particle Database of Natural Ice Crystals: Dimensions and Aspect Ratios For original submission and image(s), see ARM Research Highlights http:www.arm.govsciencehighlights...

  7. X-Ray Microscopy Reveals How Crystal Mechanics Drive Battery...

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

    Microscopy Reveals How Crystal Mechanics Drive Battery Performance Print Rechargeable lithium-ion batteries power most portable electronics and are becoming more widely used in...

  8. Electric field effects in liquid crystals with dielectric dispersion

    SciTech Connect (OSTI)

    Lavrentovich, Oleg D.

    2014-11-29

    The project is focused on the experimental and theoretical exploration of the coupling of an externally applied electric field and a nematic liquid crystal.

  9. Detection and recognition of analytes based on their crystallization patterns

    DOE Patents [OSTI]

    Morozov, Victor (Manassas, VA); Bailey, Charles L. (Cross Junction, VA); Vsevolodov, Nikolai N. (Kensington, MD); Elliott, Adam (Manassas, VA)

    2008-05-06

    The invention contemplates a method for recognition of proteins and other biological molecules by imaging morphology, size and distribution of crystalline and amorphous dry residues in droplets (further referred to as "crystallization pattern") containing predetermined amount of certain crystal-forming organic compounds (reporters) to which protein to be analyzed is added. It has been shown that changes in the crystallization patterns of a number of amino-acids can be used as a "signature" of a protein added. It was also found that both the character of changer in the crystallization patter and the fact of such changes can be used as recognition elements in analysis of protein molecules.

  10. Surface Treatment And Protection Method For Cadium Zinc Telluride Crystals

    DOE Patents [OSTI]

    Wright, Gomez W.; James, Ralph B.; Burger, Arnold; Chinn, Douglas A.

    2006-02-21

    A method for treatment of the surface of a CdZnTe (CZT) crystal that provides a native dielectric coating to reduce surface leakage currents and thereby, improve the resolution of instruments incorporating detectors using CZT crystals. A two step process is disclosed, etching the surface of a CZT crystal with a solution of the conventional bromine/methanol etch treatment, and after attachment of electrical contacts, passivating the CZT crystal surface with a solution of 10 w/o NH4F and 10 w/o H2O2 in water.

  11. Surface treatment and protection method for cadmium zinc telluride crystals

    DOE Patents [OSTI]

    Wright, Gomez W.; James, Ralph B.; Burger, Arnold; Chinn, Douglas A.

    2003-01-01

    A method for treatment of the surface of a CdZnTe (CZT) crystal that provides a native dielectric coating to reduce surface leakage currents and thereby, improve the resolution of instruments incorporating detectors using CZT crystals. A two step process is disclosed, etching the surface of a CZT crystal with a solution of the conventional bromine/methanol etch treatment, and after attachment of electrical contacts, passivating the CZT crystal surface with a solution of 10 w/o NH.sub.4 F and 10 w/o H.sub.2 O.sub.2 in water.

  12. Ultratough CVD single crystal diamond and three dimensional growth thereof

    DOE Patents [OSTI]

    Hemley, Russell J. (Washington, DC); Mao, Ho-kwang (Washington, DC); Yan, Chih-shiue (Washington, DC)

    2009-09-29

    The invention relates to a single-crystal diamond grown by microwave plasma chemical vapor deposition that has a toughness of at least about 30 MPa m.sup.1/2. The invention also relates to a method of producing a single-crystal diamond with a toughness of at least about 30 MPa m.sup.1/2. The invention further relates to a process for producing a single crystal CVD diamond in three dimensions on a single crystal diamond substrate.

  13. Single Crystal Preparation for High-Pressure Experiments in the...

    Office of Scientific and Technical Information (OSTI)

    Title: Single Crystal Preparation for High-Pressure Experiments in the Diamond Anvil Cell Most research conducted in diamond anvil cells (DAC) is performed on polycrystalline ...

  14. New Crystal Structures Lift Fog around Protein Folding

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

    New Crystal Structures Lift Fog around Protein Folding Print Nature's proteins set a high bar for nanotechnology. Macromolecules forged from peptide chains of amino acids, these...

  15. Search for: "bent crystals" | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    ... It is part of a continuing effort to measure the fundamental diffraction properties of bent crystals that are used to study various characteristics of high temperature plasmas. ...

  16. Solar cell structure incorporating a novel single crystal silicon material

    DOE Patents [OSTI]

    Pankove, Jacques I. (Princeton, NJ); Wu, Chung P. (Trenton, NJ)

    1983-01-01

    A novel hydrogen rich single crystal silicon material having a band gap energy greater than 1.1 eV can be fabricated by forming an amorphous region of graded crystallinity in a body of single crystalline silicon and thereafter contacting the region with atomic hydrogen followed by pulsed laser annealing at a sufficient power and for a sufficient duration to recrystallize the region into single crystal silicon without out-gassing the hydrogen. The new material can be used to fabricate semiconductor devices such as single crystal silicon solar cells with surface window regions having a greater band gap energy than that of single crystal silicon without hydrogen.

  17. Method for harvesting rare earth barium copper oxide single crystals

    DOE Patents [OSTI]

    Todt, Volker R. (Lemont, IL); Sengupta, Suvankar (Columbus, OH); Shi, Donglu (Cincinnati, OH)

    1996-01-01

    A method of preparing high temperature superconductor single crystals. The method of preparation involves preparing precursor materials of a particular composition, heating the precursor material to achieve a peritectic mixture of peritectic liquid and crystals of the high temperature superconductor, cooling the peritectic mixture to quench directly the mixture on a porous, wettable inert substrate to wick off the peritectic liquid, leaving single crystals of the high temperature superconductor on the porous substrate. Alternatively, the peritectic mixture can be cooled to a solid mass and reheated on a porous, inert substrate to melt the matrix of peritectic fluid while leaving the crystals melted, allowing the wicking away of the peritectic liquid.

  18. Diffraction crystals for sagittally focusing x-rays

    DOE Patents [OSTI]

    Ice, G.E.; Sparks, C.J. Jr.

    1982-06-07

    The invention is a new type of diffraction crystal designed for sagittally focusing photons of various energies. The invention is based on the discovery that such focusing is not obtainable with conventional crystals because of distortion resulting from anticlastic curvature. The new crystal comprises a monocrystalline base having a front face contoured for sagittally focusing photons and a back face provided with rigid, upstanding, stiffening ribs restricting anticlastic curvature. When mounted in a suitable bending device, the reflecting face of the crystal can be adjusted to focus photons having any one of a range of energies.

  19. Single Crystal Preparation for High-Pressure Experiments in the...

    Office of Scientific and Technical Information (OSTI)

    Experiments in the Diamond Anvil Cell Citation Details In-Document Search Title: Single Crystal Preparation for High-Pressure Experiments in the Diamond Anvil Cell You are ...

  20. Application of Spatially Resolved High Resolution Crystal Spectrometry...

    Office of Scientific and Technical Information (OSTI)

    Crystal Spectrometry to ICF Plasmas Kenneth W. Hill, et. al. 70 PLASMA PHYSICS AND FUSION TECHNOLOGY High Temperature High Temperature High resolution (3; 10 000) 1D...

  1. Method for the preparation of photochromic insulating crystals

    DOE Patents [OSTI]

    Abraham, M.M.; Boldu, J.L.; Chen, Y.; Orera, V.M.

    1984-09-28

    A method for preparing reversible-photochromic magnesium oxide (MgO) crystals is disclosed. Single crystals of MgO doped with both lithium (Li) and nickel (Ni) are grown by a conventional arc fusion method. The as-grown crystals are characterized by an amber coloration. The crystals lose the amber coloration and become photochromic when they are thermochemically reduced by heating at temperatures greater then 1000/sup 0/K in a hydrogen atmosphere. Alternate irradiation with uv and visible light result in rejuvenation and bleaching of the amber coloration, respectively.

  2. Systematic expansion of porous crystals to include large molecules | Center

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

    for Gas SeparationsRelevant to Clean Energy Technologies | Blandine Jerome Systematic expansion of porous crystals to include large molecules

  3. Crystal structure and solution characterization of the thioredoxin...

    Office of Scientific and Technical Information (OSTI)

    from Plasmodium falciparum, a constituent of an essential parasitic protein export complex Citation Details In-Document Search Title: Crystal structure and solution...

  4. Crystal Structure of MC159 Reveals Molecular Mechanism of DISC...

    Office of Scientific and Technical Information (OSTI)

    SciTech Connect Search Results Journal Article: Crystal Structure of MC159 Reveals Molecular Mechanism of DISC Assembly and FLIP Inhibition Citation Details In-Document Search ...

  5. Electrorheological crystallization of proteins and other molecules

    DOE Patents [OSTI]

    Craig, George D. (Lafayette, CA); Rupp, Bernhard (Dublin, CA)

    1996-01-01

    An electrorheological crystalline mass of a molecule is formed by dispersing the molecule in a dispersion fluid and subjecting the molecule dispersion to a uniform electrical field for a period of time during which time an electrorheological crystalline mass is formed. Molecules that may be used to form an electrorheological crystalline mass include any organic or inorganic molecule which has a permanent dipole and/or which is capable of becoming an induced dipole in the presence of an electric field. The molecules used to form the electrorheological crystalline mass are preferably macromolecules, such as biomolecules, such as proteins, nucleic acids, carbohydrates, lipoproteins and viruses. Molecules are crystallized by a method in which an electric field is maintained for a period of time after the electrorheological crystalline mass has formed during which time at least some of the molecules making up the electrorheological crystalline mass form a crystal lattice. The three dimensional structure of a molecule is determined by a method in which an electrorheological crystalline mass of the molecule is formed, an x-ray diffraction pattern of the electrorheological crystalline mass is obtained and the three dimensional structure of the molecule is calculated from the x-ray diffraction pattern.

  6. Electrorheological crystallization of proteins and other molecules

    DOE Patents [OSTI]

    Craig, G.D.; Rupp, B.

    1996-06-11

    An electrorheological crystalline mass of a molecule is formed by dispersing the molecule in a dispersion fluid and subjecting the molecule dispersion to a uniform electrical field for a period of time during which time an electrorheological crystalline mass is formed. Molecules that may be used to form an electrorheological crystalline mass include any organic or inorganic molecule which has a permanent dipole and/or which is capable of becoming an induced dipole in the presence of an electric field. The molecules used to form the electrorheological crystalline mass are preferably macromolecules, such as biomolecules, such as proteins, nucleic acids, carbohydrates, lipoproteins and viruses. Molecules are crystallized by a method in which an electric field is maintained for a period of time after the electrorheological crystalline mass has formed during which time at least some of the molecules making up the electrorheological crystalline mass form a crystal lattice. The three dimensional structure of a molecule is determined by a method in which an electrorheological crystalline mass of the molecule is formed, an X-ray diffraction pattern of the electrorheological crystalline mass is obtained and the three dimensional structure of the molecule is calculated from the X-ray diffraction pattern. 4 figs.

  7. Solution-grown crystals for neutron radiation detectors, and methods of solution growth

    DOE Patents [OSTI]

    Zaitseva, Natalia; Carman, M Leslie; Payne, Steve

    2014-10-28

    An organic crystal according to one embodiment includes an organic crystal comprising diphenylacetylene and stilbene or a stilbene derivative, the crystal having physical characteristics of formation from solution, the organic crystal exhibiting a signal response signature for neutrons from a radioactive source. A system according to one embodiment includes an organic crystal comprising diphenylacetylene and stilbene or a stilbene derivative, the crystal having physical characteristics of formation from solution, the organic crystal exhibiting a signal response signature for neutrons from a radioactive source; and a photodetector for detecting the signal response of the organic crystal. Methods of making such crystals are also provided.

  8. Surface Curvatures and Diffraction Profiles of Sagittaly Bent Laue Crystals

    SciTech Connect (OSTI)

    Shi, X.; Takacs, P.; Ghose, S.; Zhong, Z.; Rehak, M.L.; Kaznatcheev, K.; Dooryhee, E.

    2011-05-17

    The performance of a bent Laue crystal monochromator crucially depends on the sagittal and meridional bending curvatures of the crystal. To optimize the design of monochromator crystals, the surface curvatures and diffraction profiles of a set of sagittally bent Laue crystals with different aspect ratios have been studied experimentally by optical metrology and X-ray measurements. The results were confirmed with finite-element analysis using large-deformation theory. The nonlinear relationship between the curvatures necessitates an experimentally determined parameter in the theoretical modeling of the diffraction profiles. By taking into account the local stress and the aspect ratio of the sagittally bent Laue crystal, the modified analytical approach successfully predicts the rocking-curve width and the integrated reflecting power. The effect of extreme sagittal bending on the rocking curve is also discussed. To retain high reflectivity, the bending curvature should not exceed its critical value for the specified crystal geometry. Furthermore, the uniformity of the bending curvatures across the crystal surface has been examined, which suggests that the minimum crystal dimension should be approximately twice the size of the beam footprint.

  9. Use of Oriented Crystals at High-Energy Accelerators

    SciTech Connect (OSTI)

    Kotov, V.I.; Afonin, A.G.; Baranov, V.T.; Biryukov, V.M.; Ivanov, Yu.M.; Kardash, A.A.; Maisheev, V.A.; Terekhov, V.I.; Troyanov, E.F.; Fedotov, Yu.S.; Chepegin, V.N.; Chesnokov, Yu.A.

    2005-06-01

    The application of bent crystals for extracting accelerated beams from high-energy accelerators is reviewed. The results of realizing highly efficient extraction of protons from the IHEP accelerator are presented. Proposals on using oriented crystals for designing efficient positron sources at linear colliders and on developing new undulators are discussed.

  10. Synthesis, crystal structure and luminescence properties of lanthanide

    Office of Scientific and Technical Information (OSTI)

    coordination polymers with a new semirigid bridging thenylsalicylamide ligand (Journal Article) | SciTech Connect Synthesis, crystal structure and luminescence properties of lanthanide coordination polymers with a new semirigid bridging thenylsalicylamide ligand Citation Details In-Document Search Title: Synthesis, crystal structure and luminescence properties of lanthanide coordination polymers with a new semirigid bridging thenylsalicylamide ligand Two new lanthanide coordination polymers

  11. Method For Passivating Crystal Silicon Surfaces - Energy Innovation Portal

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

    Solar Photovoltaic Solar Photovoltaic Find More Like This Return to Search Method For Passivating Crystal Silicon Surfaces National Renewable Energy Laboratory Contact NREL About This Technology Publications: PDF Document Publication Silicon Surface and Heterojunction Interface Passivation Studies by Lifetime Measurements (395 KB) PDF Document Publication High-Throughput Approaches to Optimization of Crystal Silicon Surface Passivation and Heterojunction Solar Cells (837 KB) Technology Marketing

  12. Electrochemical system including lamella settler crystallizer

    DOE Patents [OSTI]

    Maimoni, Arturo (Orinda, CA)

    1988-01-01

    A crystallizer which incorporates a lamella settler and which is particularly applicable for use in batteries and power cells for electric vehicles or stationary applications. The lamella settler can be utilized for coarse particle separation or for agglomeration, and is particularly applicable to aluminum-air batteries or power cells for solving the hydrargillite (aluminum-hydroxide) removal problems from such batteries. This invention provides the advantages of very low energy consumption, turbulence, shear, cost and maintenance. Thus, due to the low shear and low turbulence of this invention, it is particularly effective in the control of aluminum hydroxide particle size distribution in the various sections of an aluminum-air system, as will as in other elecrochemical systems requiring separation for phases of different densities.

  13. Pulsed pyroelectric crystal-powered gamma source

    SciTech Connect (OSTI)

    Chen, A. X.; Antolak, A. J.; Leung, K.-N.; Raber, T. N.; Morse, D. H.

    2013-04-19

    A compact pulsed gamma generator is being developed to replace radiological sources used in commercial, industrial and medical applications. Mono-energetic gammas are produced in the 0.4 - 1.0 MeV energy range using nuclear reactions such as {sup 9}Be(d,n{gamma}){sup 10}B. The gamma generator employs an RF-driven inductively coupled plasma ion source to produce deuterium ion current densities up to 2 mA/mm{sup 2} and ampere-level current pulses can be attained by utilizing an array extraction grid. The extracted deuterium ions are accelerated to approximately 300 keV via a compact stacked pyroelectric crystal system and then bombard the beryllium target to generate gammas. The resulting microsecond pulse of gammas is equivalent to a radiological source with curie-level activity.

  14. Efg Crystal Growth Apparatus And Method

    DOE Patents [OSTI]

    Mackintosh, Brian H. (Concord, MA); Ouellette, Marc (Nashua, NH)

    2003-05-13

    An improved mechanical arrangement controls the introduction of silicon particles into an EFG (Edge-defined Film-fed Growth) crucible/die unit for melt replenishment during a crystal growth run. A feeder unit injects silicon particles upwardly through a center hub of the crucible/die unit and the mechanical arrangement intercepts the injected particles and directs them so that they drop into the melt in a selected region of the crucible and at velocity which reduces splashing, whereby to reduce the likelihood of interruption of the growth process due to formation of a solid mass of silicon on the center hub and adjoining components. The invention also comprises use of a Faraday ring to alter the ratio of the electrical currents flowing through primary and secondary induction heating coils that heat the crucible die unit and the mechanical arrangement.

  15. DNA-Guided Crystallization of Colloidal Nanoparticles

    SciTech Connect (OSTI)

    Nykypanchuk,D.; Maye, M.; van der Lelie, D.; Gang, O.

    2008-01-01

    Many nanometre-sized building blocks will readily assemble into macroscopic structures. If the process is accompanied by effective control over the interactions between the blocks and all entropic effects, then the resultant structures will be ordered with a precision hard to achieve with other fabrication methods. But it remains challenging to use self-assembly to design systems comprised of different types of building blocks--to realize novel magnetic, plasmonic and photonic metamaterials for example. A conceptually simple idea for overcoming this problem is the use of 'encodable' interactions between building blocks; this can in principle be straightforwardly implemented using biomolecules6, 7, 8, 9, 10. Strategies that use DNA programmability to control the placement of nanoparticles in one and two dimensions have indeed been demonstrated. However, our theoretical understanding of how to extend this approach to three dimensions is limited14, 15, and most experiments have yielded amorphous aggregates and only occasionally crystallites of close-packed micrometre-sized particles. Here, we report the formation of three-dimensional crystalline assemblies of gold nanoparticles mediated by interactions between complementary DNA molecules attached to the nanoparticles' surface. We find that the nanoparticle crystals form reversibly during heating and cooling cycles. Moreover, the body-centred-cubic lattice structure is temperature-tuneable and structurally open, with particles occupying only {approx}4% of the unit cell volume. We expect that our DNA-mediated crystallization approach, and the insight into DNA design requirements it has provided, will facilitate both the creation of new classes of ordered multicomponent metamaterials and the exploration of the phase behaviour of hybrid systems with addressable interactions.

  16. Ultraviolet laser beam monitor using radiation responsive crystals

    DOE Patents [OSTI]

    McCann, Michael P. (Oliver Springs, TN); Chen, Chung H. (Knoxville, TN)

    1988-01-01

    An apparatus and method for monitoring an ultraviolet laser beam includes disposing in the path of an ultraviolet laser beam a substantially transparent crystal that will produce a color pattern in response to ultraviolet radiation. The crystal is exposed to the ultraviolet laser beam and a color pattern is produced within the crystal corresponding to the laser beam intensity distribution therein. The crystal is then exposed to visible light, and the color pattern is observed by means of the visible light to determine the characteristics of the laser beam that passed through crystal. In this manner, a perpendicular cross sectional intensity profile and a longitudinal intensity profile of the ultraviolet laser beam may be determined. The observation of the color pattern may be made with forward or back scattered light and may be made with the naked eye or with optical systems such as microscopes and television cameras.

  17. First results on the SPS beam collimation with bent crystals

    SciTech Connect (OSTI)

    Scandale, W.; Robert-Demolaize, G.; Arduini, G.; Assmann, R.; Bracco, C.; Gilardoni, S.; Ippolito, V.; Laface, E.; Losito, R,; Masi, A,; Metral, E,; Previtali, V.; Redaelli, S.; Silari, M.; Tlustos, L.; Bagli, E.; Baricordi, S.; Dalpiaz, P.; Guidi, V.; Mazzolari, A.; Vincenzi, D.; Della Mea, G.; Lombardi, A.; De Salvador, D.; Vallazza, E.; Bolognini, D.; Hasan, S.; Lietti, D.; Mascagna, V.; Mattera, A.; Prest, M.; Cavoto, G.; Ludovici, L.; Mirarchi, D.; Santacesaria, R.; Valente, P.; Murtas, F.; Afonin, A.G.; Chesnokov, Yu.A.; Maisheev, V.A.; Yazynin, I.A.; Kovalenko, A.D.; Taratin, A.M.; Denisov, A.S.; Gavrikov, Yu.A.; Ivanov, Yu.M.; Lapina, L.P.; Malyarenko, L.G.; Skorobogatov, V.V.; Suvorov, V.M.; Vavilov, S.A.; Mokhov, N.; Still, D.; Markiewicz, T.; Oriunno, M.

    2010-08-23

    Experiments were performed at the CERN SPS with 120 GeV/c stored proton beams to assess the possibility of beam halo collimation assisted by bent crystals. A bent crystal was used to deflect horizontally by an angle of about 170 {micro}rad the beam halo protons in channeling states directing them into a 60 cm long tungsten absorber. The halo loss rate due to nuclear inelastic interactions of protons in the aligned crystal was up to five times smaller than for its amorphous orientation. Channeled fractions, (75 {+-} 4)% and (85 {+-} 5)% for the two tested silicon crystals, were measured by intercepting the deflected beam with another collimator located between the crystals and the absorber. The pixel detector (MEDIPIX) installed in a Roman pot inside the beam pipe was used to obtain visual images of the deflected beam.

  18. Macromolecular Crystallization with Microfluidic Free-Interface Diffusion

    SciTech Connect (OSTI)

    Segelke, B

    2005-02-24

    Fluidigm released the Topaz 1.96 and 4.96 crystallization chips in the fall of 2004. Topaz 1.96 and 4.96 are the latest evolution of Fluidigm's microfluidics crystallization technologies that enable ultra low volume rapid screening for macromolecular crystallization. Topaz 1.96 and 4.96 are similar to each other but represent a major redesign of the Topaz system and have of substantially improved ease of automation and ease of use, improved efficiency and even further reduced amount of material needed. With the release of the new Topaz system, Fluidigm continues to set the standard in low volume crystallization screening which is having an increasing impact in the field of structural genomics, and structural biology more generally. In to the future we are likely to see further optimization and increased utility of the Topaz crystallization system, but we are also likely to see further innovation and the emergence of competing technologies.

  19. Shallow melt apparatus for semicontinuous czochralski crystal growth

    DOE Patents [OSTI]

    Wang, Tihu; Ciszek, Theodore F.

    2006-01-10

    In a single crystal pulling apparatus for providing a Czochralski crystal growth process, the improvement of a shallow melt In a single crystal pulling apparatus for providing a Czochralski crystal growth process, the improvement of a shallow melt crucible (20) to eliminate the necessity supplying a large quantity of feed stock materials that had to be preloaded in a deep crucible to grow a large ingot, comprising a gas tight container a crucible with a deepened periphery (25) to prevent snapping of a shallow melt and reduce turbulent melt convection; source supply means for adding source material to the semiconductor melt; a double barrier (23) to minimize heat transfer between the deepened periphery (25) and the shallow melt in the growth compartment; offset holes (24) in the double barrier (23) to increase melt travel length between the deepened periphery (25) and the shallow growth compartment; and the interface heater/heat sink (22) to control the interface shape and crystal growth rate.

  20. EMPIRICAL MODEL FOR FORMULATION OF CRYSTAL-TOLERANT HLW GLASSES

    SciTech Connect (OSTI)

    KRUGER AA; MATYAS J; HUCKLEBERRY AR; VIENNA JD; RODRIGUEZ CA

    2012-03-07

    Historically, high-level waste (HLW) glasses have been formulated with a low liquideus temperature (T{sub L}), or temperature at which the equilibrium fraction of spinel crystals in the melt is below 1 vol % (T{sub 0.01}), nominally below 1050 C. These constraints cannot prevent the accumulation of large spinel crystals in considerably cooler regions ({approx} 850 C) of the glass discharge riser during melter idling and significantly limit the waste loading, which is reflected in a high volume of waste glass, and would result in high capital, production, and disposal costs. A developed empirical model predicts crystal accumulation in the riser of the melter as a function of concentration of spinel-forming components in glass, and thereby provides guidance in formulating crystal-tolerant glasses that would allow high waste loadings by keeping the spinel crystals small and therefore suspended in the glass.

  1. Growing intermetallic single crystals using in situ decanting

    SciTech Connect (OSTI)

    Petrovic, Cedomir; Canfield, Paul; Mellen, Jonathan

    2012-05-16

    High temperature metallic solution growth is one of the most successful and versatile methods for single crystal growth, and is particularly suited for exploratory synthesis. The method commonly utilizes a centrifuge at room temperature and is very successful for the synthesis of single crystal phases that can be decanted from the liquid below the melting point of the silica ampoule. In this paper, we demonstrate the extension of this method that enables single crystal growth and flux decanting inside the furnace at temperatures above 1200C. This not only extends the number of available metallic solvents that can be used in exploratory crystal growth but also can be particularly well suited for crystals that have a rather narrow exposed solidification surface in the equilibrium alloy phase diagram.

  2. Crystallization upon thermal annealing of a glass-forming liquid crystal in the nematic regime

    SciTech Connect (OSTI)

    Mastrangelo, J.C.; Blanton, T.N.; Chen, S.H.

    1995-04-24

    As an example of a novel class of glass-forming liquid crystals, compound (I) was synthesized and characterized to possess a nematic mesophase between {ital T}{sub {ital g}} and {ital T}{sub {ital c}} as the pristine crystal was heated beyond its {ital T}{sub {ital m}} followed by quenching to below room temperature. Differential scanning calorimetry (DSC) and x-ray diffraction techniques were employed to investigate its morphological stability. It was found that the nematic mesophase persists upon annealing for a period of up to 22 h without the appearance of new phases. However, after annealing in the nematic regime over a longer period of time, thermally activated phase transformations were observed, resulting in a new crystalline phase plus the pristine crystalline phase based on DSC thermal transition data and x-ray diffraction patterns.

  3. Spectroscopic manifestations of local crystal distortions in excited 4f states in crystals of huntite structure

    SciTech Connect (OSTI)

    Malakhovskii, A. V.; Gnatchenko, S. L.; Kachur, I. S.; Piryatinskaya, V. G.; Sukhachev, A. L.; Sokolov, A. E.; Strokova, A. Ya.; Kartashev, A. V.; Temerov, V. L.

    2013-01-15

    Optical absorption spectra of YbAl{sub 3}(BO{sub 3}){sub 4}, TmAl{sub 3}(BO{sub 3}){sub 4} and TbFe{sub 3}(BO{sub 3}){sub 4} trigonal crystals have been studied in temperature range 2-300 K. Temperature behavior of absorption lines parameters has shown, that during some f-f transitions the local environment of rare earth ions undergo distortions, which are absent in the ground state.

  4. Crystal-Tolerant Glass Approach For Mitigation Of Crystal Accumulation In Continuous Melters Processing Radioactive Waste

    SciTech Connect (OSTI)

    Kruger, Albert A.; Rodriguez, Carmen P.; Lang, Jesse B.; Huckleberry, Adam R.; Matyas, Josef; Owen, Antoinette T.

    2012-08-28

    High-level radioactive waste melters are projected to operate in an inefficient manner as they are subjected to artificial constraints, such as minimum liquidus temperature (T{sub L}) or maximum equilibrium fraction of crystallinity at a given temperature. These constraints substantially limit waste loading, but were imposed to prevent clogging of the melter with spinel crystals [(Fe, Ni, Mn, Zn)(Fe, Cr){sub 2}O{sub 4}]. In the melter, the glass discharge riser is the most likely location for crystal accumulation during idling because of low glass temperatures, stagnant melts, and small diameter. To address this problem, a series of lab-scale crucible tests were performed with specially formulated glasses to simulate accumulation of spinel in the riser. Thicknesses of accumulated layers were incorporated into empirical model of spinel settling. In addition, T{sub L} of glasses was measured and impact of particle agglomeration on accumulation rate was evaluated. Empirical model predicted well the accumulation of single crystals and/or smallscale agglomerates, but, excessive agglomeration observed in high-Ni-Fe glass resulted in an under-prediction of accumulated layers, which gradually worsen over time as an increased number of agglomerates formed. Accumulation rate of ~14.9 +- 1 nm/s determined for this glass will result in ~26 mm thick layer in 20 days of melter idling.

  5. Spatial Distribution of -Crystals in Metallocene-Made Isotactic Polypropylene Crystallized under Combined Thermal and Flow Fields

    SciTech Connect (OSTI)

    Wang, Y.; Pan, J; Mao, Y; Li, Z; Li, L; Hsiao, B

    2010-01-01

    The present Article reports the relationships between molecular orientation, formation, and spatial distribution of {gamma}-crystals in metallocene-made isotactic polypropylene (m-iPP) samples prepared by two industrial processes: conventional injection molding (CIM) and oscillatory shear injection molding (OSIM), in which combined thermal and flow fields typically exist. In particular, spatial distributions of crystallinity, fraction of {gamma}-crystal (f{gamma}) with respect to {alpha}-crystal, and lamella-branched shish-kebab structure in the shaped samples were characterized by synchrotron two-dimensional (2D) wide-angle X-ray diffraction (WAXD) and small-angle X-ray scattering (SAXS) techniques. The results showed that the crystallinity in any given region of OSIM samples was always higher than that of CIM samples. The value of f{gamma} increased monotonously from skin to core in CIM samples, whereas the corresponding f{gamma} increased nonmonotonically in OSIM samples. The spatial distribution of {gamma}-crystal in OSIM samples can be explained by the epitaxial arrangement between {gamma}- and {alpha}-crystal in a lamella-branched shish-kebab structure. In the proposed model, the parent lamellae of {alpha}-crystal provide secondary nucleation sites for daughter lamellae of {alpha}-crystal and {gamma}-crystal, and the different content of parent lamellae results in varying amounts of {gamma}-crystal. In OSIM samples, the smallest parent-daughter ratio ([R] = 1.38) in the core region led to the lowest fraction of {gamma}-crystal (0.57), but relatively higher {gamma}-crystal content (0.69) at 600 and 1200 {micro}m depth of the samples (corresponding to [R] of 4.5 and 5.8, respectively). This is consistent with the proposed model where more parent lamellae provide more nucleation sites for crystallization, thus resulting in higher content of {gamma}-crystal. The melting behavior of CIM and OSIM samples was studied by differential scanning calorimetery (DSC). The observed double-melting peaks could be explained by the melting of {gamma}- and {alpha}-crystal of the shaped samples. The f{gamma} distribution calculated from the relative areas of the peaks in the DSC scans was also consistent with the WAXD results.

  6. Review of crystal diffraction and its application to focusing energetic gamma rays

    SciTech Connect (OSTI)

    Smither, R.K.; Fernandez, P.B.; Graber, T.; von Ballmoos, P.; Naya, J.; Albernhe, F.; Vedrenne, G.; Faiz, M.

    1995-10-01

    The basic features of crystal diffraction and their application to the construction of a crystal diffraction lens for focusing energetic gamma rays are described using examples from the work preformed at the Argonne National Laboratory. Both on-axis and off-axis performance are discussed. The review includes of normal crystals, bent crystals, and crystals with variable crystal-plane spacings to develop both condenser-type lenses and point-to-point imaging lenses.

  7. Single crystal Processing and magnetic properties of gadolinium nickel

    SciTech Connect (OSTI)

    Shreve, Andrew John

    2012-11-02

    GdNi is a rare earth intermetallic material that exhibits very interesting magnetic properties. Spontaneous magnetostriction occurs in GdNi at T{sub C}, on the order of 8000ppm strain along the c-axis and only until very recently the mechanism causing this giant magnetostriction was not understood. In order to learn more about the electronic and magnetic structure of GdNi, single crystals are required for anisotropic magnetic property measurements. Single crystal processing is quite challenging for GdNi though since the rare-earth transition-metal composition yields a very reactive intermetallic compound. Many crystal growth methods are pursued in this study including crucible free methods, precipitation growths, and specially developed Bridgman crucibles. A plasma-sprayed Gd{sub 2}O{sub 3} W-backed Bridgman crucible was found to be the best means of GdNi single crystal processing. With a source of high-quality single crystals, many magnetization measurements were collected to reveal the magnetic structure of GdNi. Heat capacity and the magnetocaloric effect are also measured on a single crystal sample. The result is a thorough report on high quality single crystal processing and the magnetic properties of GdNi.

  8. Heterogeneity and dynamics in villin headpiece crystal structures

    SciTech Connect (OSTI)

    Meng, Jianmin; McKnight, Christopher James, E-mail: cjmck@bu.edu [Boston University School of Medicine (United States)

    2009-05-01

    New crystal structures of the well studied protein-folding model system villin headpiece in a new space group provide insights into the conformations available in the folded state. The villin headpiece domain (HP67) is the C-terminal F-actin-binding motif that confers F-actin-bundling activity to villin, a component of the actin bundles that support the brush-border microvilli. It has been investigated extensively by both experimental and theoretical measurements. Our laboratory, for example, has determined both its NMR and its crystal structures. This study presents the structures of HP67 and its pH-stabilized mutant (H41Y) in a different crystal form and space group. For both constructs, two molecules are found in each asymmetric unit in the new space group P6{sub 1}. While one of the two structures (Mol A) is structurally similar to our previously determined structure (Mol X), the other (Mol B) has significant deviations, especially in the N-terminal subdomain, where lattice contacts do not appear to contribute to the difference. In addition, the structurally most different crystal structure, Mol B, is actually closer to the averaged NMR structure. Harmonic motions, as suggested by the B-factor profiles, differ between these crystal structures; crystal structures from the same space group share a similar pattern. Thus, heterogeneity and dynamics are observed in different crystal structures of the same protein even for a protein as small as villin headpiece.

  9. Crystallization and preliminary crystallographic analysis of recombinant human galectin-1

    SciTech Connect (OSTI)

    Scott, Stacy A.; Scott, Ken; Blanchard, Helen

    2007-11-01

    Human galectin-1 has been cloned, expressed in E. coli, purified and crystallized in the presence of both lactose (ligand) and ?-mercaptoethanol under six different conditions. The X-ray diffraction data obtained have enabled the assignment of unit-cell parameters for two novel crystal forms of human galectin-1. Galectin-1 is considered to be a regulator protein as it is ubiquitously expressed throughout the adult body and is responsible for a broad range of cellular regulatory functions. Interest in galectin-1 from a drug-design perspective is founded on evidence of its overexpression by many cancers and its immunomodulatory properties. The development of galectin-1-specific inhibitors is a rational approach to the fight against cancer because although galectin-1 induces a plethora of effects, null mice appear normal. X-ray crystallographic structure determination will aid the structure-based design of galectin-1 inhibitors. Here, the crystallization and preliminary diffraction analysis of human galectin-1 crystals generated under six different conditions is reported. X-ray diffraction data enabled the assignment of unit-cell parameters for crystals grown under two conditions, one belongs to a tetragonal crystal system and the other was determined as monoclinic P2{sub 1}, representing two new crystal forms of human galectin-1.

  10. Optical-diffraction method for determining crystal orientation

    DOE Patents [OSTI]

    Sopori, B.L.

    1982-05-07

    Disclosed is an optical diffraction technique for characterizing the three-dimensional orientation of a crystal sample. An arbitrary surface of the crystal sample is texture etched so as to generate a pseudo-periodic diffraction grating on the surface. A laser light beam is then directed onto the etched surface, and the reflected light forms a farfield diffraction pattern in reflection. Parameters of the diffraction pattern, such as the geometry and angular dispersion of the diffracted beam are then related to grating shape of the etched surface which is in turn related to crystal orientation. This technique may be used for examining polycrystalline silicon for use in solar cells.

  11. A Crystal-Clear Solution | Y-12 National Security Complex

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

    A Crystal-Clear Solution A Crystal-Clear Solution Posted: July 22, 2013 - 3:27pm | Y-12 Report | Volume 10, Issue 1 | 2013 When he's not analyzing uranium, Ashley Stowe is finding new ways to detect it. His project to grow lithium semiconductor crystals suitable for radiation detection is the first step in solving a global shortage of helium-3, the most common element used in current detectors. In 2008, the U.S. government announced a critical shortage of helium-3, a material decidedly more

  12. First results from bent crystal extraction at the Fermilab Tevatron

    SciTech Connect (OSTI)

    The E853 Collaboration

    1996-07-01

    First results from Fermilab Experiment 953 are presented. E853 is an experiment to test the feasibility and efficiency of extracting a low intensity beam from the halo of the Tevatron using channeling in a bent silicon crystal. The motivation for the experiment is to apply crystal extraction to trans-TeV accelerators like the LHC. Extensive simulation work has been carried out. Two accelerator operating modes have been developed for crystal studies, ``kick`` mode and diffusion mode. Results from the first successful extraction in kick mode are presented.

  13. Lithium niobate single-crystal and photo-functional device

    DOE Patents [OSTI]

    Gopalan, Venkatraman (State College, PA); Mitchell, Terrence E. (Los Alamos, NM); Kitamura, Kenji (Tsukuba, JP); Furukawa, Yasunori (Tsukuba, JP)

    2001-01-01

    Provided are lithium niobate single-crystal that requires a low voltage of not larger than 10 kV/nm for its ferroelectric polarization inversion and of which the polarization can be periodically inverted with accuracy even at such a low voltage, and a photo-functional device comprising the crystal. The crystal has a molar fraction of Li.sub.2 O/(Nb.sub.2 O.sub.5 +Li.sub.2 O) of falling between 0.49 and 0.52. The photo-functional device can convert a laser ray being incident thereon.

  14. Synthesis, Crystal and Electronic Structure of the Quaternary Magnetic

    Office of Scientific and Technical Information (OSTI)

    EuTAl4Si2 (T = Rh and Ir) Compounds (Journal Article) | SciTech Connect Synthesis, Crystal and Electronic Structure of the Quaternary Magnetic EuTAl4Si2 (T = Rh and Ir) Compounds Citation Details In-Document Search Title: Synthesis, Crystal and Electronic Structure of the Quaternary Magnetic EuTAl4Si2 (T = Rh and Ir) Compounds Single crystals of the quaternary europium compounds EuRhAl4Si2 and EuIrAl4Si2 were synthesized by using the Al-Si binary eutectic as a flux. The structure of the two

  15. Methods of making composite optical devices employing polymer liquid crystal

    DOE Patents [OSTI]

    Jacobs, Stephen D. (Pittsford, NY); Marshall, Kenneth L. (Henrietta, NY); Cerqua, Kathleen A. (Fairport, NY)

    1991-01-01

    Composite optical devices using polymer liquid crystal materials both as optical and adhesive elements. The devices are made by assembling a heated polymer liquid crystal compound, while in a low viscosity form between optically transparent substrates. The molecules of the polymer are oriented, while in the liquid crystalline state and while above the glass transition temperature (T.sub.g) of the polymer, to provide the desired optical effects, such as polarization, and selective reflection. The liquid crystal polymer cements the substrates together to form an assembly providing the composite optical device.

  16. Methods of making composite optical devices employing polymer liquid crystal

    DOE Patents [OSTI]

    Jacobs, S.D.; Marshall, K.L.; Cerqua, K.A.

    1991-10-08

    Composite optical devices are disclosed using polymer liquid crystal materials both as optical and adhesive elements. The devices are made by assembling a heated polymer liquid crystal compound, while in a low viscosity form between optically transparent substrates. The molecules of the polymer are oriented, while in the liquid crystalline state and while above the glass transition temperature (T[sub g]) of the polymer, to provide the desired optical effects, such as polarization, and selective reflection. The liquid crystal polymer cements the substrates together to form an assembly providing the composite optical device. 7 figures.

  17. Solution-grown crystals for neutron radiation detectors, and methods of solution growth

    DOE Patents [OSTI]

    Zaitseva, Natalia P.; Hull, Giulia; Cherepy, Nerine J.; Payne, Stephen A.; Stoeffl, Wolfgang

    2012-06-26

    A method according to one embodiment includes growing an organic crystal from solution, the organic crystal exhibiting a signal response signature for neutrons from a radioactive source. A system according to one embodiment includes an organic crystal having physical characteristics of formation from solution, the organic crystal exhibiting a signal response signature for neutrons from a radioactive source; and a photodetector for detecting the signal response of the organic crystal. A method according to another embodiment includes growing an organic crystal from solution, the organic crystal being large enough to exhibit a detectable signal response signature for neutrons from a radioactive source. An organic crystal according to another embodiment includes an organic crystal having physical characteristics of formation from solution, the organic crystal exhibiting a signal response signature for neutrons from a radioactive source, wherein the organic crystal has a length of greater than about 1 mm in one dimension.

  18. The crystal structure of {pi}-ErBO{sub 3}: New single-crystal data for an old problem

    SciTech Connect (OSTI)

    Pitscheider, Almut [Institut fuer Allgemeine, Anorganische und Theoretische Chemie, Leopold-Franzens-Universitaet Innsbruck, Innrain 52a, A-6020 Innsbruck (Austria); Kaindl, Reinhard [Institut fuer Mineralogie und Petrographie, Leopold-Franzens-Universitaet Innsbruck, Innrain 52, A-6020 Innsbruck (Austria); Oeckler, Oliver [Department Chemie, Ludwig-Maximilians-Universitaet Muenchen, Butenandtstrasse 5-13, D-81377 Muenchen (Germany); Huppertz, Hubert, E-mail: Hubert.Huppertz@uibk.ac.a [Institut fuer Allgemeine, Anorganische und Theoretische Chemie, Leopold-Franzens-Universitaet Innsbruck, Innrain 52a, A-6020 Innsbruck (Austria)

    2011-01-15

    Single crystals of the orthoborate {pi}-ErBO{sub 3} were synthesized from Er{sub 2}O{sub 3} and B{sub 2}O{sub 3} under high-pressure/high-temperature conditions of 2 GPa and 800 {sup o}C in a Walker-type multianvil apparatus. The crystal structure was determined on the basis of single-crystal X-ray diffraction data, collected at room temperature. The title compound crystallizes in the monoclinic pseudowollastonite-type structure, space group C2/c, with the lattice parameters a=1128.4(2) pm, b=652.6(2) pm, c=954.0(2) pm, and {beta}=112.8(1){sup o} (R{sub 1}=0.0124 and wR{sub 2}=0.0404 for all data). -- graphical abstract: The first satisfying single-crystal structure determination of {pi}-ErBO{sub 3} sheds light on the extensively discussed structure of {pi}-orthoborates. The application of light pressure during the solid state synthesis yielded in high-quality crystals, due to pressure-induced crystallization. Research highlights: {yields} High-quality single crystals of {pi}-ErBO{sub 3} were prepared via high-pressure-induced crystallization. {yields} At least five different space groups for the rare-earth {pi}-orthoborates are reported. {yields} {pi}-ErBO{sub 3} is isotypic to the pseudowollastonite-type CaSiO{sub 3}. {yields} Remaining ambiguities regarding the structure of the rare-earth {pi}-orthoborates are resolved.

  19. Liquid crystal devices especially for use in liquid crystal point diffraction interferometer systems

    DOE Patents [OSTI]

    Marshall, Kenneth L. (Rochester, NY)

    2009-02-17

    Liquid crystal point diffraction interferometer (LCPDI) systems that can provide real-time, phase-shifting interferograms that are useful in the characterization of static optical properties (wavefront aberrations, lensing, or wedge) in optical elements or dynamic, time-resolved events (temperature fluctuations and gradients, motion) in physical systems use improved LCPDI cells that employ a "structured" substrate or substrates in which the structural features are produced by thin film deposition or photo resist processing to provide a diffractive element that is an integral part of the cell substrate(s). The LC material used in the device may be doped with a "contrast-compensated" mixture of positive and negative dichroic dyes.

  20. Single-Crystal Structure of a Covalent Organic Framework

    SciTech Connect (OSTI)

    Zhang, YB; Su, J; Furukawa, H; Yun, YF; Gandara, F; Duong, A; Zou, XD; Yaghi, OM

    2013-11-06

    The crystal structure of a new covalent organic framework, termed COF-320, is determined by single-crystal 3D electron diffraction using the rotation electron diffraction (RED) method for data collection. The COF crystals are prepared by an imine condensation of tetra-(4-anilyl)methane and 4,4'-biphenyldialdehyde in 1,4-dioxane at 120 degrees C to produce a highly porous 9-fold interwoven diamond net. COF-320 exhibits permanent porosity with a Langmuir surface area of 2400 m(2)/g and a methane total uptake of 15.0 wt % (176 cm(3)/cm(3)) at 25 degrees C and 80 bar. The successful determination of the structure of COF-320 directly from single-crystal samples is an important advance in the development of COF chemistry.

  1. Synthesis, Crystal and Electronic Structure of the Quaternary...

    Office of Scientific and Technical Information (OSTI)

    EuTAl4Si2 (T Rh and Ir) Compounds Citation Details In-Document Search Title: Synthesis, Crystal and Electronic Structure of the Quaternary Magnetic EuTAl4Si2 (T Rh and ...

  2. N-Terminal T4 Lysozyme Fusion Facilitates Crystallization of...

    Office of Scientific and Technical Information (OSTI)

    N-Terminal T4 Lysozyme Fusion Facilitates Crystallization of a G Protein Coupled Receptor Citation Details In-Document Search Title: N-Terminal T4 Lysozyme Fusion Facilitates...

  3. Oxidation and crystal field effects in uranium (Journal Article...

    Office of Scientific and Technical Information (OSTI)

    5, 2016 Title: Oxidation and crystal field effects in uranium Authors: Tobin, J. G. ; Yu, S.-W. ; Booth, C. H. ; Tyliszczak, T. ; Shuh, D. K. ; van der Laan, G. ; Sokaras, D. ;...

  4. Method for harvesting rare earth barium copper oxide single crystals

    DOE Patents [OSTI]

    Todt, V.R.; Sengupta, S.; Shi, D.

    1996-04-02

    A method of preparing high temperature superconductor single crystals is disclosed. The method of preparation involves preparing precursor materials of a particular composition, heating the precursor material to achieve a peritectic mixture of peritectic liquid and crystals of the high temperature superconductor, cooling the peritectic mixture to quench directly the mixture on a porous, wettable inert substrate to wick off the peritectic liquid, leaving single crystals of the high temperature superconductor on the porous substrate. Alternatively, the peritectic mixture can be cooled to a solid mass and reheated on a porous, inert substrate to melt the matrix of peritectic fluid while leaving the crystals melted, allowing the wicking away of the peritectic liquid. 2 figs.

  5. Determination of surface electric charge profile in pyroelectric crystals

    SciTech Connect (OSTI)

    Ghaderi, R.; Davani, F. Abbasi

    2014-12-08

    Pyroelectric crystals are used to produce high energy self-focused electron beams. Here, an experimental analysis in combination with simulation studies will be reported to investigate possible sources of this effect. In the experiments, the surface of crystal was divided into six separated parts and the rate of surface electric charge production was measured accordingly. A non-steady and spatially non-uniform distribution of the surface charge generation was observed, in which it tends to a uniform distribution in the course of experiment. The obtained surface electric charges from the experiments were used to simulate the electric field and potential around the crystal by COMSOL Multiphysics. It was observed that emitted electrons from the crystal surface were focused, and the non-uniformity in spatial charge is responsible for this phenomenon.

  6. Optimization of Cylindrical Bent Crystals with Small Radius

    SciTech Connect (OSTI)

    Li Zhongliang; Kang Le; Feng Liangjie; Zhao Feiyun; Xu Chaoyin

    2010-06-23

    To minimize the anticlastic curvature and lower the breaking risk of a sagittal bent crystal with a smaller bending radius, three types of crystal models including the stiffening ribs, the golden value and the assembly with metal were discussed in this paper. Overall structures of the models were predicted and the parameters were optimized by the finite element analysis method. Compared with the results of measurement by long-trace-profiler, theoretical calculations were in good agreed with practical tests. The single-crystal silicon strips glued on the titanium is preferred for the second crystal of the sagittal focusing monochromator at the NSRL-XAFS beamline. Because it not only minimizes the anticlastic distortion but also it achieves small radius less than one meter.

  7. Magneto-optical properties of biogenic photonic crystals in algae

    SciTech Connect (OSTI)

    Iwasaka, M.; Mizukawa, Y.

    2014-05-07

    In the present study, the effects of strong static magnetic fields on the structural colors of the cell covering crystals on a microalgae, coccolithophore, were investigated. The coccolithophore, Emiliania huxleyi, generates a precise assembly of calcite crystals called coccoliths by biomineralization. The coccoliths attached to the cells exhibited structural colors under side light illumination, and the colors underwent dynamic transitions when the magnetic fields were changed between 0?T and 5?T, probably due to diamagnetically induced changes of their inclination under the magnetic fields. The specific light-scattering property of individual coccoliths separated from the cells was also observed. Light scattering from a condensed suspension of coccoliths drastically decreased when magnetic fields of more than 4?T were applied parallel to the direction of observation. The magnetically aligned cell-covering crystals of the coccolithophores exhibited the properties of both a photonic crystal and a minimum micromirror.

  8. Crystal Structure of a Protein Kinase A Complex

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

    Crystal Structure of a Protein Kinase A Complex Print Protein kinase A (PKA) is an enzyme that regulates processes as diverse as growth, memory, and metabolism. In its unactivated...

  9. Invariant patterns in crystal lattices: Implications for protein folding algorithms

    SciTech Connect (OSTI)

    HART,WILLIAM E.; ISTRAIL,SORIN

    2000-06-01

    Crystal lattices are infinite periodic graphs that occur naturally in a variety of geometries and which are of fundamental importance in polymer science. Discrete models of protein folding use crystal lattices to define the space of protein conformations. Because various crystal lattices provide discretizations of the same physical phenomenon, it is reasonable to expect that there will exist invariants across lattices related to fundamental properties of the protein folding process. This paper considers whether performance-guaranteed approximability is such an invariant for HP lattice models. The authors define a master approximation algorithm that has provable performance guarantees provided that a specific sublattice exists within a given lattice. They describe a broad class of crystal lattices that are approximable, which further suggests that approximability is a general property of HP lattice models.

  10. Development of a Spatially Resolving X-Ray Crystal Spectrometer...

    Office of Scientific and Technical Information (OSTI)

    Fusion Links Development of a spatially resolving x-ray crystal spectrometer for measurement of ion-temperature "T i ... and rotation-velocity "v... profiles in ITER a... ...

  11. The Biological Implications of the PP2A Crystal Structure

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

    The Biological Implications of the PP2A Crystal Structure Print Phosphatases, enzymes that remove a phosphate group from amino-acid substrates, can be subdivided according to their...

  12. Crystal field parameters and energy levels scheme of trivalent...

    Office of Scientific and Technical Information (OSTI)

    have been modeled in the frame of Exchange Charge Model (ECM) of the crystal field theory, taken into account the geometry of systems, with actually site symmetry of the...

  13. The Biological Implications of the PP2A Crystal Structure

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

    susceptibility to pathogen infections. To shed light on the details of how PP2A works, Cho and Xu have determined the first crystal structure of the enzyme. Their structure...

  14. The Crystal Structure of Mouse Exo70 Reveals Unique Features...

    Office of Scientific and Technical Information (OSTI)

    Title: The Crystal Structure of Mouse Exo70 Reveals Unique Features of the Mammalian Exocyst Authors: Moore, Brian A. ; Robinson, Howard H. ; Xu, Zhaohui 1 ; Michigan-Med) 2 + ...

  15. T-542: SAP Crystal Reports Server Multiple Vulnerabilities

    Broader source: Energy.gov [DOE]

    Multiple vulnerabilities in SAP Crystal Reports Server 2008, which can be exploited by malicious users to disclose potentially sensitive information and by malicious people to conduct cross-site scripting attacks, manipulate certain data, and compromise a user's system.

  16. Search for: "bent crystals" | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    In channeling conditions, the beam loss rate induced by inelastic interactions of particles with the crystal nuclei is minimal. The loss reduction was about 6 for protons and about ...

  17. All-Optically Prepared and Controlled Nematic Liquid Crystal...

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

    is achieved through photo-induced anisotropy that develops in a monomolecular layer coating the inside surfaces of a liquid crystal cell.DescriptionOne of these surfaces is...

  18. Aqueous sulfate separation by crystallization of sulfate–water clusters

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

    Custelcean, Radu; Williams, Neil J.; Seipp, Charles A.

    2015-08-07

    An effective approach to separating sulfates from aqueous solutions is based on the crystallization of extended [SO4(H2O) 52-]n sulfate–water clusters with a bis(guanidinium) ligand. The ligand was generated in situ by hydrazone condensation in water, thus avoiding elaborate syntheses, tedious purifications, and organic solvents. Crystallization of sulfate–water clusters represents an alternative to the now established sulfate separation strategies that involve encapsulating the “naked” anion.

  19. Growth and characterization of lithium yttrium borate single crystals

    SciTech Connect (OSTI)

    Singh, A. K.; Singh, S. G.; Tyagi, M.; Desai, D. G.; Sen, Shashwati

    2014-04-24

    Single crystals of 0.1% Ce doped Li{sub 6}Y(BO{sub 3}){sub 3} have been grown using the Czochralski technique. The photoluminescence study of these crystals shows a broad emission at ? 420 nm corresponding to Ce{sub 3+} emission from 5d?4f energy levels. The decay profile of this emission shows a fast response of ? 28 ns which is highly desirable for detector applications.

  20. The Biological Implications of the PP2A Crystal Structure

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

    The Biological Implications of the PP2A Crystal Structure The Biological Implications of the PP2A Crystal Structure Print Wednesday, 30 January 2008 00:00 Phosphatases, enzymes that remove a phosphate group from amino-acid substrates, can be subdivided according to their substrate specificity. Myriad evidence has demonstrated that protein phosphatase 2A (PP2A), a family of serine/threonine-specific (Ser/Thr) phosphatases, regulates many, if not most, aspects of cellular activities and is a

  1. New Crystal Structures Lift Fog around Protein Folding

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

    New Crystal Structures Lift Fog around Protein Folding New Crystal Structures Lift Fog around Protein Folding Print Wednesday, 25 July 2012 00:00 Nature's proteins set a high bar for nanotechnology. Macromolecules forged from peptide chains of amino acids, these biomolecular nanomachines must first be folded into a dazzling variety of shapes and forms before they can perform the multitude of functions fundamental to life. However, the mechanisms behind the protein-folding process have remained a

  2. X-ray interferometry with spherically bent crystals (abstract)

    SciTech Connect (OSTI)

    Koch, Jeffrey A.

    2001-01-01

    Recent progress in manufacturing high-quality spherically bent crystals allows highly monochromatic x-ray beams to be produced, and allows efficient x-ray imaging with {mu}m-scale resolution. This article explores some of the constraints for x-ray interferometry utilizing spherically bent crystals and laser-produced plasma sources, and discusses several shearing interferometer concepts that might be experimentally investigated.

  3. Intrinsic carrier multiplication efficiency in bulk Si crystals evaluated

    Office of Scientific and Technical Information (OSTI)

    by optical-pump/terahertz-probe spectroscopy (Journal Article) | SciTech Connect Intrinsic carrier multiplication efficiency in bulk Si crystals evaluated by optical-pump/terahertz-probe spectroscopy Citation Details In-Document Search Title: Intrinsic carrier multiplication efficiency in bulk Si crystals evaluated by optical-pump/terahertz-probe spectroscopy We estimated the carrier multiplication efficiency in the most common solar-cell material, Si, by using optical-pump/terahertz-probe

  4. Mechanistic characterization and crystal structure of a small molecule

    Office of Scientific and Technical Information (OSTI)

    inactivator bound to plasminogen activator inhibitor-1 (Journal Article) | SciTech Connect Mechanistic characterization and crystal structure of a small molecule inactivator bound to plasminogen activator inhibitor-1 Citation Details In-Document Search Title: Mechanistic characterization and crystal structure of a small molecule inactivator bound to plasminogen activator inhibitor-1 Authors: Li, Shih-Hon ; Reinke, Ashley A. ; Sanders, Karen L. ; Emal, Cory D. ; Whisstock, James C. ; Stuckey,

  5. Patent: Method for characterization of a spherically bent crystal for

    Office of Scientific and Technical Information (OSTI)

    K.alpha. X-ray imaging of laser plasmas using a focusing monochromator geometry | DOEpatents Method for characterization of a spherically bent crystal for K.alpha. X-ray imaging of laser plasmas using a focusing monochromator geometry Citation Details Title: Method for characterization of a spherically bent crystal for K.alpha. X-ray imaging of laser plasmas using a focusing monochromator geometry

  6. Application of channeling in bent crystals to charged particle beams

    Office of Scientific and Technical Information (OSTI)

    (Conference) | SciTech Connect Application of channeling in bent crystals to charged particle beams Citation Details In-Document Search Title: Application of channeling in bent crystals to charged particle beams × You are accessing a document from the Department of Energy's (DOE) SciTech Connect. This site is a product of DOE's Office of Scientific and Technical Information (OSTI) and is provided as a public service. Visit OSTI to utilize additional information resources in energy science

  7. Crystallization Behavior of Virgin TR-55 Silicone Rubber Measured Using

    Office of Scientific and Technical Information (OSTI)

    Dynamic Mechanical Thermal Analysis with Liquid Nitrogen Cooling (Technical Report) | SciTech Connect Crystallization Behavior of Virgin TR-55 Silicone Rubber Measured Using Dynamic Mechanical Thermal Analysis with Liquid Nitrogen Cooling Citation Details In-Document Search Title: Crystallization Behavior of Virgin TR-55 Silicone Rubber Measured Using Dynamic Mechanical Thermal Analysis with Liquid Nitrogen Cooling Dynamic mechanical thermal analysis (DMTA) of virgin TR-55 silicone rubber

  8. Crystallization of Enantiomerically Pure Proteins from Quasi-Racemic

    Office of Scientific and Technical Information (OSTI)

    Mixtures: Structure Determination by X-Ray Diffraction of Isotope-Labeled Ester Insulin and Human Insulin (Journal Article) | SciTech Connect Crystallization of Enantiomerically Pure Proteins from Quasi-Racemic Mixtures: Structure Determination by X-Ray Diffraction of Isotope-Labeled Ester Insulin and Human Insulin Citation Details In-Document Search Title: Crystallization of Enantiomerically Pure Proteins from Quasi-Racemic Mixtures: Structure Determination by X-Ray Diffraction of

  9. Crystallizing Membrane Proteins in Lipidic Mesophases. A Host Lipid Screen

    Office of Scientific and Technical Information (OSTI)

    (Journal Article) | SciTech Connect Crystallizing Membrane Proteins in Lipidic Mesophases. A Host Lipid Screen Citation Details In-Document Search Title: Crystallizing Membrane Proteins in Lipidic Mesophases. A Host Lipid Screen The default lipid for the bulk of the crystallogenesis studies performed to date using the cubic mesophase method is monoolein. There is no good reason, however, why this 18-carbon, cis-monounsaturated monoacylglycerol should be the preferred lipid for all target

  10. Crystal Structures of Phosphite Dehydrogenase Provide Insights into

    Office of Scientific and Technical Information (OSTI)

    Nicotinamide Cofactor Regeneration (Journal Article) | SciTech Connect SciTech Connect Search Results Journal Article: Crystal Structures of Phosphite Dehydrogenase Provide Insights into Nicotinamide Cofactor Regeneration Citation Details In-Document Search Title: Crystal Structures of Phosphite Dehydrogenase Provide Insights into Nicotinamide Cofactor Regeneration The enzyme phosphite dehydrogenase (PTDH) catalyzes the NAD{sup +}-dependent conversion of phosphite to phosphate and represents

  11. Crystal structures of a polypeptide processing and secretion transporter

    Office of Scientific and Technical Information (OSTI)

    (Journal Article) | SciTech Connect SciTech Connect Search Results Journal Article: Crystal structures of a polypeptide processing and secretion transporter Citation Details In-Document Search Title: Crystal structures of a polypeptide processing and secretion transporter Authors: Lin, David Yin-wei ; Huang, Shuo ; Chen , Jue [1] ; HHMI) [2] + Show Author Affiliations (Rockefeller) ( Publication Date: 2015-08-28 OSTI Identifier: 1203742 Resource Type: Journal Article Resource Relation:

  12. Death Domain Assembly Mechanism Revealed by Crystal Structure of the

    Office of Scientific and Technical Information (OSTI)

    Oligomeric PIDDosome Core Complex (Journal Article) | SciTech Connect SciTech Connect Search Results Journal Article: Death Domain Assembly Mechanism Revealed by Crystal Structure of the Oligomeric PIDDosome Core Complex Citation Details In-Document Search Title: Death Domain Assembly Mechanism Revealed by Crystal Structure of the Oligomeric PIDDosome Core Complex Authors: Park, Hyun Ho ; Logette, Emmanuelle ; Rausnser, Stefan ; Cuenin, Solange ; Walz, Thomas ; Tschopp, Jurg ; Wu, Hao [1] ;

  13. Electronically- and crystal-structure-driven magnetic structures and

    Office of Scientific and Technical Information (OSTI)

    physical properties of RScSb (R = rare earth) compounds. A neutron diffraction, magnetization and heat capacity study (Journal Article) | SciTech Connect Electronically- and crystal-structure-driven magnetic structures and physical properties of RScSb (R = rare earth) compounds. A neutron diffraction, magnetization and heat capacity study Citation Details In-Document Search Title: Electronically- and crystal-structure-driven magnetic structures and physical properties of RScSb (R = rare

  14. Electronically- and crystal-structure-driven magnetic structures and

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

    physical properties of RScSb (R = rare earth) compounds. A neutron diffraction, magnetization and heat capacity study (Journal Article) | SciTech Connect Electronically- and crystal-structure-driven magnetic structures and physical properties of RScSb (R = rare earth) compounds. A neutron diffraction, magnetization and heat capacity study Citation Details In-Document Search Title: Electronically- and crystal-structure-driven magnetic structures and physical properties of RScSb (R = rare

  15. Crystal Structure of a Protein Kinase A Complex

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

    Crystal Structure of a Protein Kinase A Complex Crystal Structure of a Protein Kinase A Complex Print Wednesday, 26 October 2005 00:00 Protein kinase A (PKA) is an enzyme that regulates processes as diverse as growth, memory, and metabolism. In its unactivated state, PKA exists as a tetrameric complex of two catalytic subunits and a regulatory subunit dimer, but when the intracellular signaling molecule cyclic adenosine monophosphate (cAMP) binds to the regulatory subunit, it facilitates

  16. Magnetic charge crystals imaged in artificial spin ice

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

    Magnetic charge crystals imaged in artificial spin ice Magnetic charge crystals imaged in artificial spin ice Potential data storage and computational advances could follow August 27, 2013 Potential data storage and computational advances could follow A 3-D depiction of the honeycomb artificial spin ice topography after the annealing and cooling protocols. The light and dark colors represent the north and south magnetic poles of the islands. Image by Ian Gilbert, U. of I. Department of Physics

  17. Jefferson Lab Builds First Single Crystal Single Cell Accelerating Cavity |

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

    Jefferson Lab Single Cell Cavity This single cell cavity was made from a single crystal of niobium. Made in the same shape as the low-loss design proposed as an improvement to the baseline for the International Linear Collider (ILC), this cavity performs much better than the ILC design goal. Jefferson Lab Builds First Single Crystal Single Cell Accelerating Cavity May 18, 2005 Jefferson Lab's Institute for Superconducting Radiofrequency Science & Technology has, for the first time,

  18. Jefferson Lab Builds First Single Crystal Single Cell Accelerating Cavity |

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

    Jefferson Lab Single Cell Cavity This single cell cavity was made from a single crystal of niobium. Made in the same shape as the low-loss design proposed as an improvement to the baseline for the International Linear Collider (ILC), this cavity performs much better than the ILC design goal. Jefferson Lab Builds First Single Crystal Single Cell Accelerating Cavity Jefferson Lab's Institute for Superconducting Radiofrequency Science & Technology has, for the first time, successfully

  19. Electrochemical Solution Growth: Gallium Nitride Crystal Growth - Energy

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

    Innovation Portal Vehicles and Fuels Vehicles and Fuels Building Energy Efficiency Building Energy Efficiency Find More Like This Return to Search Electrochemical Solution Growth: Gallium Nitride Crystal Growth Sandia National Laboratories Contact SNL About This Technology Publications: PDF Document Publication Market Sheet (886 KB) Technology Marketing SummarySandia National Laboratories has developed a disruptive new crystal growth technology, called Electrochemical Solution Growth (ESG).

  20. Use of a photonic crystal for optical amplifier gain control

    DOE Patents [OSTI]

    Lin, Shawn-Yu (Albuquerque, NM); Fleming, James G. (Albuquerque, NM); El-Kady, Ihab (Albuquerque, NM)

    2006-07-18

    An optical amplifier having a uniform gain profile uses a photonic crystal to tune the density-of-states of a gain medium so as to modify the light emission rate between atomic states. The density-of-states of the gain medium is tuned by selecting the size, shape, dielectric constant, and spacing of a plurality of microcavity defects in the photonic crystal. The optical amplifier is particularly useful for the regeneration of DWDM signals in long optical fibers.

  1. Adsorption and diffusion in zeolites: the pitfall of isotypic crystal

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

    structures | Center for Gas SeparationsRelevant to Clean Energy Technologies | Blandine Jerome Adsorption and diffusion in zeolites: the pitfall of isotypic crystal structures Previous Next List Nils E.R. Zimmermann, Maciej Haranczyk, Manju Sharma, Bei Liu, Berend Smit & Frerich J. Keil, Molecular Simulations, 37, 986-989 (2011) DOI: 10.1080/08927022.2011.562502 Abstract: The influence of isotypic crystal structures on adsorption and diffusion of methane in all-silica LTA, SAS and ITE

  2. Studies on Oxide Cathode Crystals | Department of Energy

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

    Oxide Cathode Crystals Studies on Oxide Cathode Crystals 2011 DOE Hydrogen and Fuel Cells Program, and Vehicle Technologies Program Annual Merit Review and Peer Evaluation PDF icon es069_chen_2011_o.pdf More Documents & Publications Performance and Safety of Olivines and Layered Oxides Vehicle Technologies Office Merit Review 2014: Design and Synthesis of Advanced High-Energy Cathode Materials Vehicle Technologies Office Merit Review 2015: Design and Synthesis of Advanced High-Energy Cathode

  3. EIS-0500: Crystal Springs Hatchery Program; Bingham, Custer, and Lemhi

    Office of Environmental Management (EM)

    Counties, Idaho | Department of Energy 0: Crystal Springs Hatchery Program; Bingham, Custer, and Lemhi Counties, Idaho EIS-0500: Crystal Springs Hatchery Program; Bingham, Custer, and Lemhi Counties, Idaho Summary DOE's Bonneville Power Administration is preparing an EIS that will assess potential environmental impacts of funding a proposal of the Shoshone-Bannock Tribes of the Fort Hall Reservation of Idaho to construct and operate a hatchery for spring/summer Chinook salmon in the Salmon

  4. SINGLE CRYSTAL NIOBIUM TUBES FOR PARTICLE COLLIDERS ACCELERATOR CAVITIES

    SciTech Connect (OSTI)

    MURPHY, JAMES E

    2013-02-28

    The objective of this research project is to produce single crystal niobium (Nb) tubes for use as particle accelerator cavities for the Fermi laboratorys International Linear Collider project. Single crystal Nb tubes may have superior performance compared to a polycrystalline tubes because the absence of grain boundaries may permit the use of higher accelerating voltages. In addition, Nb tubes that are subjected to the high temperature, high vacuum crystallization process are very pure and well annealed. Any impurity with a significantly higher vapor pressure than Nb should be decreased by the relatively long exposure at high temperature to the high vacuum environment. After application of the single crystal process, the surfaces of the Nb tubes are bright and shiny, and the tube resembles an electro polished Nb tube. For these reasons, there is interest in single crystal Nb tubes and in a process that will produce single crystal tubes. To convert a polycrystalline niobium tube into a single crystal, the tube is heated to within a few hundred ?C of the melting temperature of niobium, which is 2477 ?C. RF heating is used to rapidly heat the tube in a narrow zone and after reaching the operating temperature, the hot zone is slowly passed along the length of the tube. For crystallization tests with Nb tubes, the traverse rate was in the range of 1-10 cm per hour. All the crystallization tests in this study were performed in a water-cooled, stainless steel chamber under a vacuum of 5 x10-6 torr or better. In earliest tests of the single crystal growth process, the Nb tubes had an OD of 1.9 cm and a wall thickness of 0.15 mm. With these relatively small Nb tubes, the single crystal process was always successful in producing single crystal tubes. In these early tests, the operating temperature was normally maintained at 2200 ?C, and the traverse rate was 5 cm per hour. In the next test series, the Nb tube size was increased to 3.8 cm OD and the wall thickness was increased 0.18 mm and eventually to 0.21 mm. Again, with these larger tubes, single crystal tubes were usually produced by the crystallization process. The power supply was generally operated at full output during these tests, and the traverse rate was 5 cm per hour. In a few tests, the traverse rate was increased to 10 cm per hour, and at the faster traverse rate, single crystal growth was not achieved. In these tests with a faster traverse rate, it was thought that the tube was not heated to a high enough temperature to achieve single crystal growth. In the next series of tests, the tube OD was unchanged at 3.8 cm and the wall thickness was increased to 0.30 mm. The increased wall thickness made it difficult to reach an operating temperature above 2,000 ?C, and although the single crystal process caused a large increase in the crystal grains, no single crystal tubes were produced. It was assumed that the operating temperature in these tests was not high enough to achieve single crystal growth. In FY 2012, a larger power supply was purchased and installed. With the new power supply, temperatures above the melting point of Nb were easily obtained regardless of the tube thickness. A series of crystallization tests was initiated to determine if indeed the operating temperature of the previous tests was too low to achieve single crystal growth. For these tests, the Nb tube OD remained at 3.8 cm and the wall thickness was 0.30 mm. The first test had an operating temperature of 2,000 ?C. and the operating temperature was increased by 50 ?C increments for each successive test. The final test was very near the Nb melting temperature, and indeed, the Nb tube eventually melted in the center of the tube. These tests showed that higher temperatures did yield larger grain sizes if the traverse rate was held constant at 5 cm per hour, but no single crystal tubes were produced even at the highest operating temperature. In addition, slowing the traverse rate to as low as 1 cm per hour did not yield a single crystal tube regardless of operating temperature. At this time, it

  5. Flexoelectricity of a Calamitic Liquid Crystal Elastomer Swollen with a Bent-core Liquid Crystal

    SciTech Connect (OSTI)

    Chambers, M.; Verduzco, R; Gleeson, J; Sprunt, S; Jakli, A

    2009-01-01

    We have measured the electric current induced by mechanical distortion of a calamitic liquid crystal elastomer (LCE) swollen with a low molecular weight bent-core nematic (BCN) liquid crystal, and have determined, for the first time, the bend flexoelectric coefficient e{sub 3} of such a BCN-LCE composite. In one method, we utilize air-pressure to induce a mechanical bend deformation and flexoelectric polarization in a BCN-LCE film, and then measure the polarization current as a function of time. An alternative technique uses a rotary-motor driven scotch yoke to periodically flex the BCN-LCE; in this case, the magnitude and phase of the induced current are recorded via a lock-in amplifier. The flexoelectric coefficient, e{sub 3}, was found to be {approx}20 nC/cm{sup 2}, and is stable in magnitude from room temperature to {approx}65 C. It is about one third the value measured in samples of the pure BCN; this fraction corresponds closely to the molar concentration of BCN in the LCE. The flexoelectric current increases linearly with the magnitude of the bend deformation and decays with frequency. These observations indicate a promising way forward towards producing very low-cost, self-standing, rugged electromechanical energy conversion devices.

  6. Fuel Performance Experiments on the Atomistic Level, Studying Fuel Through Engineered Single Crystal UO2

    SciTech Connect (OSTI)

    Burgett, Eric; Deo, Chaitanya; Phillpot, Simon

    2015-05-08

    Fuel Performance Experiments on the Atomistic Level, Studying Fuel Through Engineered Single Crystal UO2

  7. Large single domain 123 material produced by seeding with single crystal rare earth barium copper oxide single crystals

    DOE Patents [OSTI]

    Todt, Volker (Lemont, IL); Miller, Dean J. (Darien, IL); Shi, Donglu (Oak Park, OH); Sengupta, Suvankar (Columbus, OH)

    1998-01-01

    A method of fabricating bulk YBa.sub.2 Cu.sub.3 O.sub.x where compressed powder oxides and/or carbonates of Y and Ba and Cu present in mole ratios to form YBa.sub.2 Cu.sub.3 O.sub.x are heated in the presence of a Nd.sub.1+x Ba.sub.2-x Cu.sub.3 O.sub.y seed crystal to a temperature sufficient to form a liquid phase in the YBa.sub.2 Cu.sub.3 O.sub.x while maintaining the seed crystal solid. The materials are slowly cooled to provide a YBa.sub.2 Cu.sub.3 O.sub.x material having a predetermined number of domains between 1 and 5. Crack-free single domain materials can be formed using either plate shaped seed crystals or cube shaped seed crystals with a pedestal of preferential orientation material.

  8. On the formulation of a crystal plasticity model.

    SciTech Connect (OSTI)

    Marin, Esteban B.

    2006-08-01

    This report presents the formulation of a crystal elasto-viscoplastic model and the corresponding integration scheme. The model is suitable to represent the isothermal, anisotropic, large deformation of polycrystalline metals. The formulation is an extension of a rigid viscoplastic model to account for elasticity effects, and incorporates a number of changes with respect to a previous formulation [Marin & Dawson, 1998]. This extension is formally derived using the well-known multiplicative decomposition of the deformation gradient into an elastic and plastic components, where the elastic part is additionally decomposed into the elastic stretch V{sup e} and the proper orthogonal R{sup e} tensors. The constitutive equations are written in the intermediate, stress-free configuration obtained by unloading the deformed crystal through the elastic stretch V{sup e-}. The model is framed in a thermodynamic setting, and developed initially for large elastic strains. The crystal equations are then specialized to the case of small elastic strains, an assumption typically valid for metals. The developed integration scheme is implicit and proceeds by separating the spherical and deviatoric crystal responses. An ''approximate'' algorithmic material moduli is also derived for applications in implicit numerical codes. The model equations and their integration procedure have been implemented in both a material point simulator and a commercial finite element code. Both implementations are validated by solving a number of examples involving aggregates of either face centered cubic (FCC) or hexagonal close-packed (HCP) crystals subjected to different loading paths.

  9. Analysis of Crystal Lattice Deformation by Ion Channeling

    SciTech Connect (OSTI)

    Jozwik, Przemyslaw A.; Sathish, N.; Nowicki, L.; Jagielski, Jacek; Turos, Andrzej W.; Kovarik, Libor; Arey, Bruce W.; Shutthanandan, V.; Jiang, Weilin; Dyczewski, J.; Barcz, A.

    2013-05-01

    A model of dislocations has been developed for the use in Monte Carlo simulations of ion channeling spectra obtained for defected crystals. High resolution transmission electron microscopy micrographs show that the dominant type of defects in the majority of ion irradiated crystals are dislocations. The RBS/channeling spectrum is then composed of two components: one is due to direct scattering on randomly displaced atoms and the second one is related to beam defocussing on dislocations, which produce predominantly crystal lattice distortions, i.e. bent channels. In order to provide a correct analysis of backscattering spectra for the crystals containing dislocations we have modified the existing Monte Carlo simulation code "McChasy". A new version of the code has been developed by implementing dislocations on the basis of the Peierls-Nabarro model. Parameters of the model have been determined from the high resolution transmission electron microscopy data. The newly developed method has been used to study the Ar-ion bombarded SrTiO3 samples. The best fit to the Rutherford backscattering/channeling spectra has been obtained by optimizing the linear combination of two kinds of defects: displaced atoms and bent channels. The great virtue of the Monte Carlo simulation is that unlike a traditional dechanneling analysis it allows quantitative analysis of crystals containing a mixture of different types of defects.

  10. Technique for thermodynamic crystallization temperature of brine fluids

    SciTech Connect (OSTI)

    Clark, D.E.; Hubbard, J.T.

    1983-03-01

    The application of high density solids free brine fluids has proven to be technically and economically successful in hydrocarbon completion and workover operations. The use of inorganic salts such as calcium chloride, calcium bromide, zinc bromide, and sodium bromide has contributed to the development of complex salt systems. As the density and complexity of these systems becomes more detailed, the requirement for proper fluid design becomes increasingly important. When a brine solution is cooled sufficiently, a temperature is reached where the solution will be saturated. A further decrease in temperature will result in the precipitation of salt from the solution. The temperature at which this transpires, provided no super-cooling occurs, is the crystallization point of the solution. A correctly formulated solids free brine should have the optimum crystallization point for the temperature conditions it will encounter. A recently developed semiautomatic procedure constructs a cooling curve plot of each brine tested. This cooling curve plot allows the determination of the super-cooling potential, the Thermodynamic Crystallization Temperature, and the Last Crystal To Dissolve Temperature. The device provides a permanent record of the cooling curve with repeatable accuracy, which assists in the development of error free brine formulation tables, brine density, and/or crystallization point adjustments, and brine analysis.

  11. Excitation enhancement and extraction enhancement with photonic crystals

    DOE Patents [OSTI]

    Shapira, Ofer; Soljacic, Marin; Zhen, Bo; Chua, Song-Liang; Lee, Jeongwon; Joannopoulos, John

    2015-03-03

    Disclosed herein is a system for stimulating emission from at least one an emitter, such as a quantum dot or organic molecule, on the surface of a photonic crystal comprising a patterned dielectric substrate. Embodiments of this system include a laser or other source that illuminates the emitter and the photonic crystal, which is characterized by an energy band structure exhibiting a Fano resonance, from a first angle so as to stimulate the emission from the emitter at a second angle. The coupling between the photonic crystal and the emitter may result in spectral and angular enhancement of the emission through excitation and extraction enhancement. These enhancement mechanisms also reduce the emitter's lasing threshold. For instance, these enhancement mechanisms enable lasing of a 100 nm thick layer of diluted organic molecules solution with reduced threshold intensity. This reduction in lasing threshold enables more efficient organic light emitting devices and more sensitive molecular sensing.

  12. Volume Reflection of a Proton Beam in a Bent Crystal

    SciTech Connect (OSTI)

    Ivanov, Yu. M.; Petrunin, A. A.; Skorobogatov, V. V.; Gavrikov, Yu. A.; Gelamkov, A. V.; Lapina, L. P.; Schetkovsky, A. I.; Vavilov, S. A.; Baranov, V. I.; Chesnokov, Yu. A.; Afonin, A. G.; Baranov, V. T.; Chepegin, V. N.; Guidi, V.; Vomiero, A.

    2006-10-06

    Volume reflection predicted in the mid-1980s by Taratin and Vorobiev has been observed for the first time in the interactions of a 70 GeV proton beam with a short bent crystal. Incident protons deviate from convex atomic planes in the bulk of the crystal as a result of coherent interaction with bent lattice around the tangency point of particle trajectory with a curved atomic plane. The deflection angle 2{theta}{sub R} was found to be (39.5{+-}2.0) {mu}rad, or (1.65{+-}0.08){theta}{sub c} in terms of the critical angle for channeling. The process has a large probability with respect to channeling and takes place in the angular range equal to the bend angle of atomic planes. It could possibly open new fields of application of crystals in high-energy particle beam optics.

  13. Shallow Melt Apparatus for Semicontinuous Czochralski Crystal Growth

    DOE Patents [OSTI]

    Wang, T.; Ciszek, T. F.

    2006-01-10

    In a single crystal pulling apparatus for providing a Czochralski crystal growth process, the improvement of a shallow melt crucible (20) to eliminate the necessity supplying a large quantity of feed stock materials that had to be preloaded in a deep crucible to grow a large ingot, comprising a gas tight container a crucible with a deepened periphery (25) to prevent snapping of a shallow melt and reduce turbulent melt convection; source supply means for adding source material to the semiconductor melt; a double barrier (23) to minimize heat transfer between the deepened periphery (25) and the shallow melt in the growth compartment; offset holes (24) in the double barrier (23) to increase melt travel length between the deepened periphery (25) and the shallow growth compartment; and the interface heater/heat sink (22) to control the interface shape and crystal growth rate.

  14. Defect topologies in chiral liquid crystals confined to mesoscopic channels

    SciTech Connect (OSTI)

    Schlotthauer, Sergej Skutnik, Robert A.; Stieger, Tillmann; Schoen, Martin

    2015-05-21

    We present Monte Carlo simulations in the grand canonical and canonical ensembles of a chiral liquid crystal confined to mesochannels of variable sizes and geometries. The mesochannels are taken to be quasi-infinite in one dimension but finite in the two other directions. Under thermodynamic conditions chosen and for a selected value of the chirality coupling constant, the bulk liquid crystal exhibits structural characteristics of a blue phase II. This is established through the tetrahedral symmetry of disclination lines and the characteristic simple-cubic arrangement of double-twist helices formed by the liquid-crystal molecules along all three axes of a Cartesian coordinate system. If the blue phase II is then exposed to confinement, the interplay between its helical structure, various anchoring conditions at the walls of the mesochannels, and the shape of the mesochannels gives rise to a broad variety of novel, qualitative disclination-line structures that are reported here for the first time.

  15. Toward crystal design in organic conductors and superconductors.

    SciTech Connect (OSTI)

    Geiser, U.

    1999-04-23

    We have seen that many different types of intermolecular interactions in organic conducting cation radical salts. Hydrogen bonding between the donor molecules and the anions is weak but not negligible. The ionic Madelung energy is insufficient to completely intersperse anions and cations, thus the layers favored by the van der Waals interactions remain intact. The search for new conducting and superconducting salts has been mainly by trial-and-error methods, even though simple substitutions have been employed in order to obtain isostructural analogs of successful (e.g., superconducting) salts. However, even seemingly minor substitutions sometimes destroy the packing type, and different crystal structures result. Simulations with the aim at predicting crystal structures have not succeeded, mainly because the different interaction types are of comparable energy, and the delocalized and partial charges render the calculations of the ionic terms extremely unreliable. Clearly, the development of suitable crystal modeling techniques with predictive capabilities is one of the great needs of the field.

  16. Acoustic transfer of protein crystals from agarose pedestals to micromeshes for high-throughput screening

    SciTech Connect (OSTI)

    Cuttitta, Christina M.; Ericson, Daniel L.; Scalia, Alexander; Roessler, Christian G.; Teplitsky, Ella; Joshi, Karan; Campos, Olven; Agarwal, Rakhi; Allaire, Marc; Orville, Allen M.; Sweet, Robert M.; Soares, Alexei S.

    2015-01-01

    An acoustic high-throughput screening method is described for harvesting protein crystals and combining the protein crystals with chemicals such as a fragment library. Acoustic droplet ejection (ADE) is an emerging technology with broad applications in serial crystallography such as growing, improving and manipulating protein crystals. One application of this technology is to gently transfer crystals onto MiTeGen micromeshes with minimal solvent. Once mounted on a micromesh, each crystal can be combined with different chemicals such as crystal-improving additives or a fragment library. Acoustic crystal mounting is fast (2.33 transfers s{sup ?1}) and all transfers occur in a sealed environment that is in vapor equilibrium with the mother liquor. Here, a system is presented to retain crystals near the ejection point and away from the inaccessible dead volume at the bottom of the well by placing the crystals on a concave agarose pedestal (CAP) with the same chemical composition as the crystal mother liquor. The bowl-shaped CAP is impenetrable to crystals. Consequently, gravity will gently move the crystals into the optimal location for acoustic ejection. It is demonstrated that an agarose pedestal of this type is compatible with most commercially available crystallization conditions and that protein crystals are readily transferred from the agarose pedestal onto micromeshes with no loss in diffraction quality. It is also shown that crystals can be grown directly on CAPs, which avoids the need to transfer the crystals from the hanging drop to a CAP. This technology has been used to combine thermolysin and lysozyme crystals with an assortment of anomalously scattering heavy atoms. The results point towards a fast nanolitre method for crystal mounting and high-throughput screening.

  17. Aqueous sulfate separation by crystallization of sulfatewater clusters

    SciTech Connect (OSTI)

    Custelcean, Radu; Williams, Neil J.; Seipp, Charles A.

    2015-08-07

    An effective approach to separating sulfates from aqueous solutions is based on the crystallization of extended [SO4(H2O) 52-]n sulfatewater clusters with a bis(guanidinium) ligand. The ligand was generated in situ by hydrazone condensation in water, thus avoiding elaborate syntheses, tedious purifications, and organic solvents. Crystallization of sulfatewater clusters represents an alternative to the now established sulfate separation strategies that involve encapsulating the naked anion.

  18. On calculating the equilibrium structure of molecular crystals.

    SciTech Connect (OSTI)

    Mattsson, Ann Elisabet; Wixom, Ryan R.; Mattsson, Thomas Kjell Rene

    2010-03-01

    The difficulty of calculating the ambient properties of molecular crystals, such as the explosive PETN, has long hampered much needed computational investigations of these materials. One reason for the shortcomings is that the exchange-correlation functionals available for Density Functional Theory (DFT) based calculations do not correctly describe the weak intermolecular van der Waals' forces present in molecular crystals. However, this weak interaction also poses other challenges for the computational schemes used. We will discuss these issues in the context of calculations of lattice constants and structure of PETN with a number of different functionals, and also discuss if these limitations can be circumvented for studies at non-ambient conditions.

  19. Process of making cryogenically cooled high thermal performance crystal optics

    DOE Patents [OSTI]

    Kuzay, T.M.

    1992-06-23

    A method is disclosed for constructing a cooled optic wherein one or more cavities are milled, drilled or formed using casting or ultrasound laser machining techniques in a single crystal base and filled with porous material having high thermal conductivity at cryogenic temperatures. A non-machined strain-free single crystal can be bonded to the base to produce superior optics. During operation of the cooled optic, N[sub 2] is pumped through the porous material at a sub-cooled cryogenic inlet temperature and with sufficient system pressure to prevent the fluid bulk temperature from reaching saturation. 7 figs.

  20. Device for isolation of seed crystals during processing of solution

    DOE Patents [OSTI]

    Montgomery, Kenneth E. (Tracy, CA); Zaitseva, Natalia P. (Livermore, CA); Deyoreo, James J. (Livermore, CA); Vital, Russell L. (Tracy, CA)

    1999-01-01

    A device for isolation of see crystals during processing of solutions. The device enables a seed crystal to be introduced into the solution without exposing the solution to contaminants or to sources of drying and cooling. The device constitutes a seed protector which allows the seed to be present in the growth solution during filtration and overheating operations while at the same time preventing the seed from being dissolved by the under saturated solution. When the solution processing has been completed and the solution cooled to near the saturation point, the seed protector is opened, exposing the seed to the solution and allowing growth to begin.

  1. Hole Localization in Molecular Crystals from Hybrid Density Functional Theory

    SciTech Connect (OSTI)

    Sai, Na; Barbara, Paul F.; Leung, Kevin

    2011-06-02

    We use first-principles computational methods to examine hole trapping in organic molecular crystals. We present a computational scheme based on the tuning of the fraction of exact exchange in hybrid density functional theory to eliminate the many-electron self-interaction error. With small organic molecules, we show that this scheme gives accurate descriptions of ionization and dimer dissociation. We demonstrate that the excess hole in perfect molecular crystals forms self-trapped molecular polarons. The predicted absolute ionization potentials of both localized and delocalized holes are consistent with experimental values.

  2. Apparatus And Method For Producing Single Crystal Metallic Objects

    DOE Patents [OSTI]

    Huang, Shyh-Chin (Latham, NY); Gigliotti, Jr., Michael Francis X. (Scotia, NY); Rutkowski, Stephen Francis (Duanesburg, NY); Petterson, Roger John (Fultonville, NY); Svec, Paul Steven (Scotia, NY)

    2006-03-14

    A mold is provided for enabling casting of single crystal metallic articles including a part-defining cavity, a sorter passage positioned vertically beneath and in fluid communication with the part-defining cavity, and a seed cavity positioned vertically beneath and in fluid communication with the sorter passage. The sorter passage includes a shape suitable for encouraging a single crystal structure in solidifying molten metal. Additionally, a portion of the mold between the sorter passage and the part-defining cavity includes a notch for facilitating breakage of a cast article proximate the notch during thermal stress build-up, so as to prevent mold breakage or the inclusion of part defects.

  3. Polarization Studies of Resonant Forbidden Reflections in Liquid Crystals

    SciTech Connect (OSTI)

    Fernandes, P.; Barois, P.; Nguyen, H. T.; Wang, S. T.; Liu, Z. Q.; McCoy, B. K.; Huang, C. C.; Pindak, R.; Caliebe, W.

    2007-11-30

    We report the results of resonant x-ray diffraction experiments performed on thick films of a biaxial liquid crystal made of achiral bent-core molecules. Polarization properties of forbidden reflections are observed as a function of the sample rotation angle {phi} about the scattering vector Q for the first time on a fluid material. The experimental data are successfully analyzed within a tensor structure factor model by taking the nonperfect alignment of the liquid crystal into account. The local structure of the B{sub 2} mesophase is hence determined to be SmC{sub S}P{sub A}.

  4. Computer simulation of beam steering by crystal channeling

    SciTech Connect (OSTI)

    Biryukov, V.

    1995-04-01

    The Monte Carlo computer program CATCH for the simulation of planar channeling in bent crystals is presented. The program tracks a charged particle through the deformed crystal lattice with the use of the continuous-potential approximation and by taking into account the processes of both single and multiple scattering on electrons and nuclei. The output consists of the exit angular distributions, the energy loss spectra, and the spectra of any close-encounter process of interest. The program predictions for the feed-out and feed-in rates, energy loss spectra, and beam bending efficiency are compared with the recent experimental data.

  5. A micro-structured ion-implanted magnonic crystal

    SciTech Connect (OSTI)

    Obry, Bjoern; Pirro, Philipp; Chumak, Andrii V.; Ciubotaru, Florin; Serga, Alexander A.; Hillebrands, Burkard; Braecher, Thomas; Graduate School Materials Science in Mainz, D-67663 Kaiserslautern ; Osten, Julia; Fassbender, Juergen

    2013-05-20

    We investigate spin-wave propagation in a microstructured magnonic-crystal waveguide fabricated by localized ion implantation. The irradiation caused a periodic variation in the saturation magnetization along the waveguide. As a consequence, the spin-wave transmission spectrum exhibits a set of frequency bands, where spin-wave propagation is suppressed. A weak modification of the saturation magnetization by 7% is sufficient to decrease the spin-wave transmission in the band gaps by a factor of 10. These results evidence the applicability of localized ion implantation for the fabrication of efficient micron- and nano-sized magnonic crystals for magnon spintronic applications.

  6. Nonequilibrium quasiparticle relaxation dynamics in single crystals of

    Office of Scientific and Technical Information (OSTI)

    hole- and electron-doped BaFe2As2 (Journal Article) | SciTech Connect Nonequilibrium quasiparticle relaxation dynamics in single crystals of hole- and electron-doped BaFe2As2 Citation Details In-Document Search Title: Nonequilibrium quasiparticle relaxation dynamics in single crystals of hole- and electron-doped BaFe2As2 Authors: Torchinsky, Darius H. ; McIver, James W. ; Hsieh, David ; Chen, G. F. ; Luo, J. L. ; Wang, N. L. ; Gedik, Nuh Publication Date: 2011-09-13 OSTI Identifier: 1100755

  7. High-pressure stability relations, crystal structures, and physical

    Office of Scientific and Technical Information (OSTI)

    properties of perovskite and post-perovskite of NaNiF{sub 3} (Journal Article) | SciTech Connect High-pressure stability relations, crystal structures, and physical properties of perovskite and post-perovskite of NaNiF{sub 3} Citation Details In-Document Search Title: High-pressure stability relations, crystal structures, and physical properties of perovskite and post-perovskite of NaNiF{sub 3} NaNiF{sub 3} perovskite was found to transform to post-perovskite at 16-18 GPa and 1273-1473 K.

  8. Dimensions and aspect ratios of natural ice crystals

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

    Um, J.; McFarquhar, G. M.; Hong, Y. P.; Lee, S. -S.; Jung, C. H.; Lawson, R. P.; Mo, Q.

    2015-04-15

    During the 2006 Tropical Warm Pool International Cloud Experiment (TWP-ICE) in the tropics, the 2008 Indirect and Semi-Direct Aerosol Campaign (ISDAC) in the Arctic, and the 2010 Small PARTicles In CirrUS (SPARTICUS) campaign at mid-latitudes, high-resolution images of ice crystals were recorded by a Cloud Particle Imager at temperatures (T) between -87 and 0 °C. The projected maximum dimension (D'), length (L'), and width (W') of pristine columns, plates, and component bullets of bullet rosettes were measured using newly developed software, the Ice Crystal Ruler. The number of bullets in each bullet rosette was also measured. Column crystals were furthermore » distinguished as either horizontally oriented columns or columns with other orientations to eliminate any orientation effect on the measured dimensions. The dimensions and aspect ratios (AR, the dimension of the major axis divided by the dimension of the minor axis) of crystals were determined as functions of temperature, geophysical location, and type of cirrus. Dimensions of crystals generally increased with temperature. Columns and bullets had larger dimensions (i.e., W') of the minor axis (i.e., a axis) for a given dimension (i.e., D' orL') of the major axis (i.e., c axis), and thus smaller AR, as T increased, whereas this trend did not occur for plate crystals. The average number of branches in bullet rosettes was 5.50 ± 1.35 during three campaigns and 6.32 ± 1.34 (5.46 ± 1.34; 4.95 ± 1.01) during TWP-ICE (SPARTICUS; ISDAC). The AR of bullets increased with the number of branches in bullet rosettes. Most dimensions of crystals and ARs of columnar crystals measured during SPARTICUS were larger than those measured during TWP-ICE and ISDAC at −67 < T < -35 °C and at −40 < T < −15 °C, respectively. The relative occurrence of varying pristine habits depended strongly on cirrus type (i.e., anvil or non-anvil clouds), with plates especially occurring more frequently in anvils. The L–W relationships of columns derived using current data exhibited a strong dependence on temperature; similar relationships determined in previous studies were within the range of the current data.« less

  9. Dimensions and aspect ratios of natural ice crystals

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

    Um, J.; McFarquhar, G. M.; Hong, Y. P.; Lee, S. -S.; Jung, C. H.; Lawson, R. P.; Mo, Q.

    2014-12-10

    During the 2006 Tropical Warm Pool International Cloud Experiment (TWP-ICE) in the Tropics, the 2008 Indirect and Semi-Direct Aerosol Campaign (ISDAC) in the Arctic, and the 2010 Small PARTicles In CirrUS (SPARTICUS) campaign in mid-latitudes, high-resolution images of ice crystals were recorded by a Cloud Particle Imager at temperatures (T) between -87 and 0 °C. The projected maximum dimension (D'), length (L'), and width (W') of pristine columns, plates, and component bullets of bullet rosettes were measured using newly developed software, the Ice Crystal Ruler. The number of bullets in each bullet rosette was also measured. Column crystals were furthermore » distinguished as either horizontally oriented columns or columns with other orientations to eliminate any orientation effect on the measured dimensions. Dimensions and aspect ratios (AR, dimension of major axis divided by dimension of minor axis) of crystals were determined as functions of temperature, geophysical location, and type of cirrus. Dimensions of crystals generally increased as temperature increased. Columns and bullets had larger dimensions (i.e., W') of the minor axis (i.e., a axis) for a given dimension (i.e., D' or L') of the major axis (i.e., c axis), and thus smaller AR, as T increased, whereas this trend did not occur for plate crystals. The average number of branches in bullet rosettes was 5.50±1.35 during three campaigns and 6.32±1.34 (5.46±1.34; 4.95±1.01) during TWP-ICE (SPARTICUS; ISDAC). The AR of bullets increased with the number of branches in bullet rosettes. Most dimensions of crystals and ARs of columnar crystals measured during SPARTICUS were larger than those measured during TWP-ICE and ISDAC at −67 < T < −35 °C and at −40 < T < −15 °C, respectively. The relative occurrence of varying pristine habits depended strongly on cirrus type (i.e., anvil or non-anvil clouds), with plates especially occurring more frequently in anvils. The L–W relationships of columns derived using current data exhibited a strong dependence on temperature; similar relationship determined in previous studies were within the range of the current data.« less

  10. Automated identification and indexing of dislocations in crystal interfaces

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

    Stukowski, Alexander; Bulatov, Vasily V.; Arsenlis, Athanasios

    2012-10-31

    Here, we present a computational method for identifying partial and interfacial dislocations in atomistic models of crystals with defects. Our automated algorithm is based on a discrete Burgers circuit integral over the elastic displacement field and is not limited to specific lattices or dislocation types. Dislocations in grain boundaries and other interfaces are identified by mapping atomic bonds from the dislocated interface to an ideal template configuration of the coherent interface to reveal incompatible displacements induced by dislocations and to determine their Burgers vectors. Additionally, the algorithm generates a continuous line representation of each dislocation segment in the crystal andmore » also identifies dislocation junctions.« less

  11. Apparatus to study crystal channeling and volume reflection phenomena at

    Office of Scientific and Technical Information (OSTI)

    the SPS H8 beamline (Journal Article) | SciTech Connect Apparatus to study crystal channeling and volume reflection phenomena at the SPS H8 beamline Citation Details In-Document Search Title: Apparatus to study crystal channeling and volume reflection phenomena at the SPS H8 beamline A high performance apparatus has been designed and built by the H8-RD22 collaboration for the study of channeling and volume reflection phenomena in the interaction of 400 GeV/c protons with bent silicon

  12. Gradient index liquid crystal devices and method of fabrication thereof

    DOE Patents [OSTI]

    Lee, Jae-Cheul (Rochester, NY); Jacobs, Stephen (Pittsford, NY)

    1991-01-01

    Laser beam apodizers using cholesteric liquid crystals provides soft edge profile by use of two separate cholesteric liquid crystal mixtures with different selective reflection bands which in an overlap region have a gradient index where reflectivity changes as a function of position. The apodizers can be configured as a one-dimensional beam apod INTRODUCTION The U.S. government has rights in the invention under Contract No. DE-FC03-85DP40200 between the University of Rochester and the Department of Energy.

  13. Gradient index liquid crystal devices and method of fabrication thereof

    DOE Patents [OSTI]

    Lee, J.C.; Jacobs, S.

    1991-10-29

    Laser beam apodizers using cholesteric liquid crystals provides soft edge profile by use of two separate cholesteric liquid crystal mixtures with different selective reflection bands which in an overlap region have a gradient index where reflectivity changes as a function of position. The apodizers can be configured as a one-dimensional beam apod INTRODUCTION The U.S. government has rights in the invention under Contract No. DE-FC03-85DP40200 between the University of Rochester and the Department of Energy.

  14. Device for isolation of seed crystals during processing of solution

    DOE Patents [OSTI]

    Montgomery, K.E.; Zaitseva, N.P.; Deyoreo, J.J.; Vital, R.L.

    1999-05-18

    A device is described for isolation of seed crystals during processing of solutions. The device enables a seed crystal to be introduced into the solution without exposing the solution to contaminants or to sources of drying and cooling. The device constitutes a seed protector which allows the seed to be present in the growth solution during filtration and overheating operations while at the same time preventing the seed from being dissolved by the under saturated solution. When the solution processing has been completed and the solution cooled to near the saturation point, the seed protector is opened, exposing the seed to the solution and allowing growth to begin. 3 figs.

  15. Superconducting properties in single crystals of the topological nodal

    Office of Scientific and Technical Information (OSTI)

    semimetal PbTaSe 2 (Journal Article) | SciTech Connect Superconducting properties in single crystals of the topological nodal semimetal PbTaSe 2 Citation Details In-Document Search This content will become publicly available on February 21, 2017 Title: Superconducting properties in single crystals of the topological nodal semimetal PbTaSe 2 Authors: Zhang, Cheng-Long ; Yuan, Zhujun ; Bian, Guang ; Xu, Su-Yang ; Zhang, Xiao ; Hasan, M. Zahid ; Jia, Shuang Publication Date: 2016-02-22 OSTI

  16. Process of making cryogenically cooled high thermal performance crystal optics

    DOE Patents [OSTI]

    Kuzay, Tuncer M. (Naperville, IL)

    1992-01-01

    A method for constructing a cooled optic wherein one or more cavities are milled, drilled or formed using casting or ultrasound laser machining techniques in a single crystal base and filled with porous material having high thermal conductivity at cryogenic temperatures. A non-machined strain-free single crystal can be bonded to the base to produce superior optics. During operation of the cooled optic, N.sub.2 is pumped through the porous material at a sub-cooled cryogenic inlet temperature and with sufficient system pressure to prevent the fluid bulk temperature from reaching saturation.

  17. Temperature cycling vapor deposition HgI.sub.2 crystal growth

    DOE Patents [OSTI]

    Schieber, Michael M.; Beinglass, Israel; Dishon, Giora

    1977-01-01

    A method and horizontal furnace for vapor phase growth of HgI.sub.2 crystals which utilizes controlled axial and radial airflow to maintain the desired temperature gradients. The ampoule containing the source material is rotated while axial and radial air tubes are moved in opposite directions during crystal growth to maintain a desired distance and associated temperature gradient with respect to the growing crystal, whereby the crystal interface can advance in all directions, i.e., radial and axial according to the crystallographic structure of the crystal. Crystals grown by this method are particularly applicable for use as room-temperature nuclear radiation detectors.

  18. A comparative study of inverted-opal titania photonic crystals made from polymer and silica colloidal crystal templates

    SciTech Connect (OSTI)

    Kuai, S.-L.; Truong, V.-V.; Hache, Alain; Hu, X.-F.

    2004-12-01

    Photonic crystals with an inverted-opal structure using polymer and silica colloidal crystal templates were prepared and compared. We show that the behaviors of the template during the removal process and heat treatment are determinant factors on the crystal formation. While both templates result in ordered macroporous structures, the optical quality in each case is quite different. The removal of the polymer template by sintering causes a large shrinkage of the inverted framework and produces a high density of cracks in the sample. With a silica template, sintering actually improves the quality of the inverted structure by enhancing the template's mechanical stability, helping increase the filling fraction, and consolidating the titania framework. The role of the other important factors such as preheating and multiple infiltrations is also investigated.

  19. High order reflectivity of graphite (HOPG) crystals for x ray...

    Office of Scientific and Technical Information (OSTI)

    at 12.6 keV to 0.5 mrad at 22.1 keV. The current study indicates that HOPG crystals are suitable for measuring scattering signals from high energy x ray sources (E ge 20 keV). ...

  20. The Los Alamos National Laboratory precision double crystal spectrometer

    SciTech Connect (OSTI)

    Morgan, D.V.; Stevens, C.J.; Liefield, R.J.

    1994-03-01

    This report discusses the following topics on the LANL precision double crystal X-ray spectrometer: Motivation for construction of the instrument; a brief history of the instrument; mechanical systems; motion control systems; computer control system; vacuum system; alignment program; scan programs; observations of the copper K{alpha} lines; and characteristics and specifications.

  1. Phonon-enhanced crystal growth and lattice healing

    DOE Patents [OSTI]

    Buonassisi, Anthony; Bertoni, Mariana; Newman, Bonna

    2013-05-28

    A system for modifying dislocation distributions in semiconductor materials is provided. The system includes one or more vibrational sources for producing at least one excitation of vibrational mode having phonon frequencies so as to enhance dislocation motion through a crystal lattice.

  2. Applications of the second virial coefficient: protein crystallization and solubility

    SciTech Connect (OSTI)

    Wilson, William W.; DeLucas, Lawrence J.

    2014-04-30

    This article highlights some of the ground-based studies emanating from NASAs Microgravity Protein Crystal Growth (PCG) program, and includes a more detailed discussion of the history and the progress made in one of the NASA-funded PCG investigations involving the use of measured second virial coefficients (B values) as a diagnostic indicator of solution conditions conducive to protein crystallization. This article begins by highlighting some of the ground-based studies emanating from NASAs Microgravity Protein Crystal Growth (PCG) program. This is followed by a more detailed discussion of the history of and the progress made in one of the NASA-funded PCG investigations involving the use of measured second virial coefficients (B values) as a diagnostic indicator of solution conditions conducive to protein crystallization. A second application of measured B values involves the determination of solution conditions that improve or maximize the solubility of aqueous and membrane proteins. These two important applications have led to several technological improvements that simplify the experimental expertise required, enable the measurement of membrane proteins and improve the diagnostic capability and measurement throughput.

  3. A novel inert crystal delivery medium for serial femtosecond crystallography

    SciTech Connect (OSTI)

    Conrad, Chelsie E.; Basu, Shibom; James, Daniel; Wang, Dingjie; Schaffer, Alexander; Roy-Chowdhury, Shatabdi; Zatsepin, Nadia A.; Aquila, Andrew; Coe, Jesse; Gati, Cornelius; Hunter, Mark S.; Koglin, Jason E.; Kupitz, Christopher; Nelson, Garrett; Subramanian, Ganesh; White, Thomas A.; Zhao, Yun; Zook, James; Boutet, Sbastien; Cherezov, Vadim; Spence, John C. H.; Fromme, Raimund; Weierstall, Uwe; Fromme, Petra

    2015-06-30

    Serial femtosecond crystallography (SFX) has opened a new era in crystallography by permitting nearly damage-free, room-temperature structure determination of challenging proteins such as membrane proteins. In SFX, femtosecond X-ray free-electron laser pulses produce diffraction snapshots from nanocrystals and microcrystals delivered in a liquid jet, which leads to high protein consumption. A slow-moving stream of agarose has been developed as a new crystal delivery medium for SFX. It has low background scattering, is compatible with both soluble and membrane proteins, and can deliver the protein crystals at a wide range of temperatures down to 4C. Using this crystal-laden agarose stream, the structure of a multi-subunit complex, phycocyanin, was solved to 2.5 resolution using 300 g of microcrystals embedded into the agarose medium post-crystallization. The agarose delivery method reduces protein consumption by at least 100-fold and has the potential to be used for a diverse population of proteins, including membrane protein complexes.

  4. A novel inert crystal delivery medium for serial femtosecond crystallography

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

    Conrad, Chelsie E.; Basu, Shibom; James, Daniel; Wang, Dingjie; Schaffer, Alexander; Roy-Chowdhury, Shatabdi; Zatsepin, Nadia A.; Aquila, Andrew; Coe, Jesse; Gati, Cornelius; et al

    2015-06-30

    Serial femtosecond crystallography (SFX) has opened a new era in crystallography by permitting nearly damage-free, room-temperature structure determination of challenging proteins such as membrane proteins. In SFX, femtosecond X-ray free-electron laser pulses produce diffraction snapshots from nanocrystals and microcrystals delivered in a liquid jet, which leads to high protein consumption. A slow-moving stream of agarose has been developed as a new crystal delivery medium for SFX. It has low background scattering, is compatible with both soluble and membrane proteins, and can deliver the protein crystals at a wide range of temperatures down to 4°C. Using this crystal-laden agarose stream, themore » structure of a multi-subunit complex, phycocyanin, was solved to 2.5 Å resolution using 300 µg of microcrystals embedded into the agarose medium post-crystallization. The agarose delivery method reduces protein consumption by at least 100-fold and has the potential to be used for a diverse population of proteins, including membrane protein complexes.« less

  5. Photonic crystal surface-emitting lasers enabled by an accidental Dirac point

    DOE Patents [OSTI]

    Chua, Song Liang; Lu, Ling; Soljacic, Marin

    2014-12-02

    A photonic-crystal surface-emitting laser (PCSEL) includes a gain medium electromagnetically coupled to a photonic crystal whose energy band structure exhibits a Dirac cone of linear dispersion at the center of the photonic crystal's Brillouin zone. This Dirac cone's vertex is called a Dirac point; because it is at the Brillouin zone center, it is called an accidental Dirac point. Tuning the photonic crystal's band structure (e.g., by changing the photonic crystal's dimensions or refractive index) to exhibit an accidental Dirac point increases the photonic crystal's mode spacing by orders of magnitudes and reduces or eliminates the photonic crystal's distributed in-plane feedback. Thus, the photonic crystal can act as a resonator that supports single-mode output from the PCSEL over a larger area than is possible with conventional PCSELs, which have quadratic band edge dispersion. Because output power generally scales with output area, this increase in output area results in higher possible output powers.

  6. Femtosecond X-ray Diffraction From Two-Dimensional Protein Crystals...

    Office of Scientific and Technical Information (OSTI)

    Femtosecond X-ray Diffraction From Two-Dimensional Protein Crystals Citation Details In-Document Search Title: Femtosecond X-ray Diffraction From Two-Dimensional Protein Crystals...

  7. Road Map for Development of Crystal-Tolerant High Level Waste...

    Office of Scientific and Technical Information (OSTI)

    Road Map for Development of Crystal-Tolerant High Level Waste Glasses Citation Details In-Document Search Title: Road Map for Development of Crystal-Tolerant High Level Waste...

  8. Calibration of Spherically Bent Crystals used in X-Ray Spectroscopy...

    Office of Scientific and Technical Information (OSTI)

    Conference: Calibration of Spherically Bent Crystals used in X-Ray Spectroscopy. Citation Details In-Document Search Title: Calibration of Spherically Bent Crystals used in X-Ray...

  9. Ultrafast Dynamic Response of Single Crystal PETN and Beta-HMX...

    Office of Scientific and Technical Information (OSTI)

    Conference: Ultrafast Dynamic Response of Single Crystal PETN and Beta-HMX Citation Details In-Document Search Title: Ultrafast Dynamic Response of Single Crystal PETN and Beta-HMX...

  10. A Look Through the Crystal Ball at the Future of Automobile Battery...

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

    A Look Through the Crystal Ball at the Future of Automobile Battery Recycling Title A Look Through the Crystal Ball at the Future of Automobile Battery Recycling Publication Type...

  11. Light trapping in thin film solar cells using textured photonic crystal

    DOE Patents [OSTI]

    Yi, Yasha (Somerville, MA); Kimerling, Lionel C. (Concord, MA); Duan, Xiaoman (Amesbury, MA); Zeng, Lirong (Cambridge, MA)

    2009-01-27

    A solar cell includes a photoactive region that receives light. A photonic crystal is coupled to the photoactive region, wherein the photonic crystal comprises a distributed Bragg reflector (DBR) for trapping the light.

  12. Acoustic transfer of protein crystals from agarose pedestals to micromeshes for high-throughput screening

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

    Cuttitta, Christina M.; Ericson, Daniel L.; Scalia, Alexander; Roessler, Christian G.; Teplitsky, Ella; Joshi, Karan; Campos, Olven; Agarwal, Rakhi; Allaire, Marc; Orville, Allen M.; et al

    2014-06-01

    Acoustic droplet ejection (ADE) is an emerging technology with broad applications in serial crystallography such as growing, improving and manipulating protein crystals. One application of this technology is to gently transfer crystals onto MiTeGen micromeshes with minimal solvent. Once mounted on a micromesh, each crystal can be combined with different chemicals such as crystal-improving additives or a fragment library. Acoustic crystal mounting is fast (2.33 transfers s-1) and all transfers occur in a sealed environment that is in vapor equilibrium with the mother liquor. Here, a system is presented to retain crystals near the ejection point and away from themore » inaccessible dead volume at the bottom of the well by placing the crystals on a concave agarose pedestal (CAP) with the same chemical composition as the crystal mother liquor. The bowl-shaped CAP is impenetrable to crystals. Consequently, gravity will gently move the crystals into the optimal location for acoustic ejection. It is demonstrated that an agarose pedestal of this type is compatible with most commercially available crystallization conditions and that protein crystals are readily transferred from the agarose pedestal onto micromeshes with no loss in diffraction quality. It is also shown that crystals can be grown directly on CAPs, which avoids the need to transfer the crystals from the hanging drop to a CAP. This technology has been used to combine thermolysin and lysozyme crystals with an assortment of anomalously scattering heavy atoms. The results point towards a fast nanolitre method for crystal mounting and high-throughput screening.« less

  13. World's largest single crystal of gold verified by Los Alamos instruments

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

    Los Alamos verifies largest single gold crystal World's largest single crystal of gold verified by Los Alamos instruments Using Lujan Center's HIPPO instrument, researchers probed the specimen with neutrons to gather critical information December 22, 2014 World's largest single crystal of gold verified by Los Alamos instruments Neutron diffraction data collected on the single-crystal diffraction (SCD) instrument at the Lujan Center, from the Venezuelan gold sample, indicate that the sample is a

  14. Increase of bulk optical damage threshold fluences of KDP crystals by laser irradiation and heat treatment

    DOE Patents [OSTI]

    Swain, J.E.; Stokowski, S.E.; Milam, D.; Kennedy, G.C.; Rainer, F.

    1982-07-07

    The bulk optical damage threshold fluence of potassium dihydrogen phosphate (KDP) crystals is increased by irradiating the crystals with laser pulses of duration 1 to 20 nanoseconds of increasing fluence, below the optical damage threshold fluence for untreated crystals, or by baking the crystals for times of the order of 24 hours at temperatures of 110 to 165/sup 0/C, or by a combination of laser irradiation and baking.

  15. Method and apparatus for producing monochromatic radiography with a bent laue crystal

    DOE Patents [OSTI]

    Zhong, Zhong (Apt. I 1131 Chaping 700 E. Loop Rd., Stony Brook, NY 11790); Chapman, Leroy Dean (4 Vermont Cir., Bolingbrook, IL 60440); Thomlinson, William C. (32 E. Masem, East Patchogue, NY 11772)

    2000-03-14

    A method and apparatus for producing a monochromatic beam. A plurality of beams are generated from a polyenergetic source. The beams are then transmitted through a bent crystal, preferably a bent Laue crystal, having a non-cylindrical shape. A position of the bent crystal is rocked with respect to the polyenergetic source until a plurality of divergent monochromatic beams are emitted from the bent crystal.

  16. On the observation of multiple volume reflection from different planes inside one bent crystal

    SciTech Connect (OSTI)

    Guidi, Vincenzo; Mazzolari, Andrea; Tikhomirov, Victor

    2010-06-15

    An interpretation of the first experiment on the observation of 400 GeV proton multiple volume reflection from different skew planes of one bent crystal (MVROC) is given. The possibilities of experimental observation of MVROC at lower particle energies are demonstrated. New features of the effect of particle capture into the channeling regime by bent skew planes are revealed as well as optimal choice of main crystal axis, crystal thickness, and beam orientation with respect to the crystal is discussed.

  17. Self-standing quasi-mosaic crystals for focusing hard X-rays

    SciTech Connect (OSTI)

    Camattari, Riccardo; Guidi, Vincenzo; Bellucci, Valerio; Neri, Ilaria; Frontera, Filippo; Jentschel, Michael

    2013-05-15

    A quasi mosaic bent crystal for high-resolution diffraction of X and {gamma} rays has been realized. A net curvature was imprinted to the crystal thanks to a series of superficial grooves to keep the curvature without external devices. The crystal highlights very high diffraction efficiency due to quasi mosaic curvature. Quasi mosaic crystals of this kind are proposed for the realization of a high-resolution focusing Laue lens for hard X-rays.

  18. Method and apparatus for producing monochromatic radiography with a bent Laue crystal

    SciTech Connect (OSTI)

    2000-03-14

    A method and apparatus are disclosed for producing a monochromatic beam. A plurality of beams are generated from a polyenergetic source. The beams are then transmitted through a bent crystal, preferably a bent Laue crystal, having a non-cylindrical shape. A position of the bent crystal is rocked with respect to the polyenergetic source until a plurality of divergent monochromatic beams are emitted from the bent crystal.

  19. Acoustic transfer of protein crystals from agarose pedestals to micromeshes for high-throughput screening

    SciTech Connect (OSTI)

    Cuttitta, Christina M.; Ericson, Daniel L.; Scalia, Alexander; Roessler, Christian G.; Teplitsky, Ella; Joshi, Karan; Campos, Olven; Agarwal, Rakhi; Allaire, Marc; Orville, Allen M.; Sweet, Robert M.; Soares, Alexei S.

    2014-06-01

    Acoustic droplet ejection (ADE) is an emerging technology with broad applications in serial crystallography such as growing, improving and manipulating protein crystals. One application of this technology is to gently transfer crystals onto MiTeGen micromeshes with minimal solvent. Once mounted on a micromesh, each crystal can be combined with different chemicals such as crystal-improving additives or a fragment library. Acoustic crystal mounting is fast (2.33 transfers s-1) and all transfers occur in a sealed environment that is in vapor equilibrium with the mother liquor. Here, a system is presented to retain crystals near the ejection point and away from the inaccessible dead volume at the bottom of the well by placing the crystals on a concave agarose pedestal (CAP) with the same chemical composition as the crystal mother liquor. The bowl-shaped CAP is impenetrable to crystals. Consequently, gravity will gently move the crystals into the optimal location for acoustic ejection. It is demonstrated that an agarose pedestal of this type is compatible with most commercially available crystallization conditions and that protein crystals are readily transferred from the agarose pedestal onto micromeshes with no loss in diffraction quality. It is also shown that crystals can be grown directly on CAPs, which avoids the need to transfer the crystals from the hanging drop to a CAP. This technology has been used to combine thermolysin and lysozyme crystals with an assortment of anomalously scattering heavy atoms. The results point towards a fast nanolitre method for crystal mounting and high-throughput screening.

  20. A scanning force microscopy study on the drawing of solution crystallized

    Office of Scientific and Technical Information (OSTI)

    UHMW-PE (Conference) | SciTech Connect Conference: A scanning force microscopy study on the drawing of solution crystallized UHMW-PE Citation Details In-Document Search Title: A scanning force microscopy study on the drawing of solution crystallized UHMW-PE Drawing of solution crystallized UHMW-PE has been monitored by scanning force microscopy (SFM). The work is focused on the transformation of lamellae to fibrilla crystals within the necking region ({lambda} = 1-10). SFM allows

  1. Growth and characterization of 4-chloro-3-nitrobenzophenone single crystals using vertical Bridgman technique

    SciTech Connect (OSTI)

    Aravinth, K. Babu, G. Anandha Ramasamy, P.

    2014-04-24

    4-chloro-3-nitrobenzophenone (4C3N) has been grown by using vertical Bridgman technique. The grown crystal was confirmed by Powder X-ray diffraction analysis. The crystalline perfection of the grown crystal was examined by high-resolution X-ray diffraction study. The fluorescence spectra of grown 4C3N single crystals exhibit emission peak at 575 nm. The micro hardness measurements were used to analyze the mechanical property of the grown crystal.

  2. Inclusion property of Cs, Sr, and Ba impurities in LiCl crystal formed by layer-melt crystallization

    SciTech Connect (OSTI)

    Choi, Jung-Hoon; Cho, Yung-Zun; Lee, Tae-Kyo; Eun, Hee-Chul; Kim, Jun-Hong; Park, Hwan-Seo; Kim, In-Tae; Park, Geun-Il

    2013-07-01

    Pyroprocessing is one of the promising technologies enabling the recycling of spent nuclear fuels from a commercial light water reactor (LWR). In general, pyroprocessing uses dry molten salts as electrolytes. In particular, LiCl waste salt after pyroprocessing contains highly radioactive I/II group fission products mainly composed of Cs, Sr, and Ba impurities. Therefore, it is beneficial to reuse LiCl salt in the pyroprocessing as an electrolyte for economic and environmental issues. Herein, to understand the inclusion property of impurities within LiCl crystal, the physical properties such as lattice parameter change, bulk modulus, and substitution enthalpy of a LiCl crystal having 0-6 at% Cs{sup +} or Ba{sup 2+} impurities under existence of 1 at% Sr{sup 2+} impurity were calculated via the first-principles density functional theory. The substitution enthalpy of LiCl crystals having 1 at% Sr{sup 2+} showed slightly decreased value than those without Sr{sup 2+} impurity. Therefore, through the substitution enthalpy calculation, it is expected that impurities will be incorporated within LiCl crystal as co-existed form rather than as a single component form. (authors)

  3. Large single domain 123 material produced by seeding with single crystal rare earth barium copper oxide single crystals

    DOE Patents [OSTI]

    Todt, V.; Miller, D.J.; Shi, D.; Sengupta, S.

    1998-07-07

    A method of fabricating bulk YBa{sub 2}Cu{sub 3}O{sub x} where compressed powder oxides and/or carbonates of Y and Ba and Cu present in mole ratios to form YBa{sub 2}Cu{sub 3}O{sub x} are heated in the presence of a Nd{sub 1+x}Ba{sub 2{minus}x}Cu{sub 3}O{sub y} seed crystal to a temperature sufficient to form a liquid phase in the YBa{sub 2}Cu{sub 3}O{sub x} while maintaining the seed crystal solid. The materials are slowly cooled to provide a YBa{sub 2}Cu{sub 3}O{sub x} material having a predetermined number of domains between 1 and 5. Crack-free single domain materials can be formed using either plate shaped seed crystals or cube shaped seed crystals with a pedestal of preferential orientation material. 7 figs.

  4. Crystal structure, growth and characterization of LiPbB?O??: A new congruent melting nonlinear optical crystal

    SciTech Connect (OSTI)

    Xia, M.J.; Li, R.K.

    2013-05-01

    A new congruent-melting crystal LiPbB?O?? (LPBO) has been grown and its structure was determined by single crystal X-ray diffraction. LPBO crystallizes in a polar space group R3c with a large unit cell of a=b=21.649(11) , c=17.193(11) , and Z=24. The basic anionic unit, (B?O?)?? group, is connected by terminal O atoms to build an infinite [(B?O?)?]? helical chain along the c axis. Second harmonic generation (SHG) measurements of the title compound indicate that LPBO can be phase matchable and its SHG coefficient is almost equal to that of KDP, which is about 3.3 times that of its analog BaLiB?O??. This significant enhancement of the SHG effect can be tentatively attributed to the lone pair Pb? cations with severely distorted coordination. LPBO has a wide transparent region from 410 to 2500 nm with a UV absorption edge about 261 nm according to the reflectance spectra. - Graphical abstract: The crystal structure of LiPbB?O?? composed of the (B?O?)?? anionic group and the lone pair Pb and Li polyhedra along c axis. Highlights: A new congruent-melt NLO crystal LiPbB?O?? (LPBO) has been grown. The basic structural unit of LPBO is B?O? group same as that found in LiB?O?. LPBO is phase matchable with SHG signal 10 times that of its Ba-analog. LPBO is highly transparent within 4101700 nm with a UV cut-off of 261 nm.

  5. Recent T980 Crystal Collimation Studies at the Tevatron Exploiting a Pixel Detector System and a Multi-Strip Crystal Array

    SciTech Connect (OSTI)

    Still, D.; Annala, G.E.; Carrigan, R.A.; Drozhdin, A.I.; Johnson, T.R.; Mokhov, N.V.; Previtali, V.; Rivera, R.; Shiltsev, V.; Zagel, J.; Zvoda, V.V.; / /CERN /INFN, Pisa / /

    2012-05-15

    With the shutdown of the Tevatron, the T-980 crystal collimation experiment at Fermilab has been successfully completed. Results of dedicated beam studies in May 2011 are described in this paper. For these studies, two multi-strip crystals were installed in the vertical goniometer and an O-shaped crystal installed in a horizontal goniometer. A two-plane CMS pixel detector was also installed in order to enhance the experiment with the capability to image the profile of crystal channeled or multiple volume reflected beam. The experiment successfully imaged channeled beam from a crystal for 980-GeV protons for the first time. This new enhanced hardware yielded impressive results. The performance and characterization of the crystals studied have been very reproducible over time and consistent with simulations.

  6. Electromagnetic Wave Propagation in Two-Dimensional Photonic Crystals

    SciTech Connect (OSTI)

    Stavroula Foteinopoulou

    2003-12-12

    In this dissertation, they have undertaken the challenge to understand the unusual propagation properties of the photonic crystal (PC). The photonic crystal is a medium where the dielectric function is periodically modulated. These types of structures are characterized by bands and gaps. In other words, they are characterized by frequency regions where propagation is prohibited (gaps) and regions where propagation is allowed (bands). In this study they focus on two-dimensional photonic crystals, i.e., structures with periodic dielectric patterns on a plane and translational symmetry in the perpendicular direction. They start by studying a two-dimensional photonic crystal system for frequencies inside the band gap. The inclusion of a line defect introduces allowed states in the otherwise prohibited frequency spectrum. The dependence of the defect resonance state on different parameters such as size of the structure, profile of incoming source, etc., is investigated in detail. For this study, they used two popular computational methods in photonic crystal research, the Finite Difference Time Domain method (FDTD) and the Transfer Matrix Method (TMM). The results for the one-dimensional defect system are analyzed, and the two methods, FDTD and TMM, are compared. Then, they shift their attention only to periodic two-dimensional crystals, concentrate on their band properties, and study their unusual refractive behavior. Anomalous refractive phenomena in photonic crystals included cases where the beam refracts on the ''wrong'' side of the surface normal. The latter phenomenon, is known as negative refraction and was previously observed in materials where the wave vector, the electric field, and the magnetic field form a left-handed set of vectors. These materials are generally called left-handed materials (LHM) or negative index materials (NIM). They investigated the possibility that the photonic crystal behaves as a LHM, and how this behavior relates with the observed negatively refractive phenomena. They found that in the PC system, negative refraction is neither a prerequisite nor guarantees left-handed behavior. They examined carefully the condition to obtain left-handed behavior in the PC. They proposed a wedge type of experiment, in accordance with the experiment performed on the traditional LHM, to test these conditions. They found that for certain frequencies the PC shows left-handed behavior and acts in some respects like a homogeneous medium with a negative refractive index. they used the realistic PC system for this case to show how negative refraction occurs at the interface between a material with a positive and a material with a negative refractive index. Their findings indicate that the formation of the negatively refracted beam is not instantaneous and involves a transient time. With this time-dependent analysis, they were able to address previous controversial issues about negative refraction concerning causality and the speed of light limit. Finally, they attempt a systematic study of anomalous refractive phenomena that can occur at the air-PC interface. They observe cases where only a single refracted beam (in the positive or negative direction) is present, as well as cases with birefringence. they classify these different effects according to their origin and type of propagation (left-handed or not). For a complete study of the system, they also obtain expressions for the energy and group velocities, and show their equality. For cases with very low index contrast, band folding becomes an artificiality. They discuss the validity of their findings when they move to the limit of photonic crystals with a low index modulation.

  7. Automated High Throughput Protein Crystallization Screening at Nanoliter Scale and Protein Structural Study on Lactate Dehydrogenase

    SciTech Connect (OSTI)

    Fenglei Li

    2006-08-09

    The purposes of our research were: (1) To develop an economical, easy to use, automated, high throughput system for large scale protein crystallization screening. (2) To develop a new protein crystallization method with high screening efficiency, low protein consumption and complete compatibility with high throughput screening system. (3) To determine the structure of lactate dehydrogenase complexed with NADH by x-ray protein crystallography to study its inherent structural properties. Firstly, we demonstrated large scale protein crystallization screening can be performed in a high throughput manner with low cost, easy operation. The overall system integrates liquid dispensing, crystallization and detection and serves as a whole solution to protein crystallization screening. The system can dispense protein and multiple different precipitants in nanoliter scale and in parallel. A new detection scheme, native fluorescence, has been developed in this system to form a two-detector system with a visible light detector for detecting protein crystallization screening results. This detection scheme has capability of eliminating common false positives by distinguishing protein crystals from inorganic crystals in a high throughput and non-destructive manner. The entire system from liquid dispensing, crystallization to crystal detection is essentially parallel, high throughput and compatible with automation. The system was successfully demonstrated by lysozyme crystallization screening. Secondly, we developed a new crystallization method with high screening efficiency, low protein consumption and compatibility with automation and high throughput. In this crystallization method, a gas permeable membrane is employed to achieve the gentle evaporation required by protein crystallization. Protein consumption is significantly reduced to nanoliter scale for each condition and thus permits exploring more conditions in a phase diagram for given amount of protein. In addition, evaporation rate can be controlled or adjusted in this method during the crystallization process to favor either nucleation or growing processes for optimizing crystallization process. The protein crystals gotten by this method were experimentally proven to possess high x-ray diffraction qualities. Finally, we crystallized human lactate dehydrogenase 1 (H4) complexed with NADH and determined its structure by x-ray crystallography. The structure of LDH/NADH displays a significantly different structural feature, compared with LDH/NADH/inhibitor ternary complex structure, that subunits in LDH/NADH complex show open conformation or two conformations on the active site while the subunits in LDH/NADH/inhibitor are all in close conformation. Multiple LDH/NADH crystals were obtained and used for x-ray diffraction experiments. Difference in subunit conformation was observed among the structures independently solved from multiple individual LDH/NADH crystals. Structural differences observed among crystals suggest the existence of multiple conformers in solution.

  8. Acquisition of Single Crystal Growth and Characterization Equipment

    SciTech Connect (OSTI)

    Maple, M. Brian; Zocco, Diego A.

    2008-12-09

    Final Report for DOE Grant No. DE-FG02-04ER46178 'Acquisition of Single Crystal Growth and Characterization Equipment'. There is growing concern in the condensed matter community that the need for quality crystal growth and materials preparation laboratories is not being met in the United States. It has been suggested that there are too many researchers performing measurements on too few materials. As a result, many user facilities are not being used optimally. The number of proficient crystal growers is too small. In addition, insufficient attention is being paid to the enterprise of finding new and interesting materials, which is the driving force behind much of condensed matter research and, ultimately, technology. While a detailed assessment of this situation is clearly needed, enough evidence of a problem already exists to compel a general consensus that the situation must be addressed promptly. This final report describes the work carried out during the last four years in our group, in which a state-of-the-art single crystal growth and characterization facility was established for the study of novel oxides and intermetallic compounds of rare earth, actinide and transition metal elements. Research emphasis is on the physics of superconducting (SC), magnetic, heavy fermion (HF), non-Fermi liquid (NFL) and other types of strongly correlated electron phenomena in bulk single crystals. Properties of these materials are being studied as a function of concentration of chemical constituents, temperature, pressure, and magnetic field, which provide information about the electronic, lattice, and magnetic excitations at the root of various strongly correlated electron phenomena. Most importantly, the facility makes possible the investigation of material properties that can only be achieved in high quality bulk single crystals, including magnetic and transport phenomena, studies of the effects of disorder, properties in the clean limit, and spectroscopic and scattering studies through efforts with numerous collaborators. These endeavors will assist the effort to explain various outstanding theoretical problems, such as order parameter symmetries and electron-pairing mechanisms in unconventional superconductors, the relationship between superconductivity and magnetic order in certain correlated electron systems, the role of disorder in non-Fermi liquid behavior and unconventional superconductivity, and the nature of interactions between localized and itinerant electrons in these materials. Understanding the mechanisms behind strongly correlated electron behavior has important technological implications.

  9. Experiment and simulation on one-dimensional plasma photonic crystals

    SciTech Connect (OSTI)

    Zhang, Lin; Ouyang, Ji-Ting

    2014-10-15

    The transmission characteristics of microwaves passing through one-dimensional plasma photonic crystals (PPCs) have been investigated by experiment and simulation. The PPCs were formed by a series of discharge tubes filled with argon at 5?Torr that the plasma density in tubes can be varied by adjusting the discharge current. The transmittance of X-band microwaves through the crystal structure was measured under different discharge currents and geometrical parameters. The finite-different time-domain method was employed to analyze the detailed properties of the microwaves propagation. The results show that there exist bandgaps when the plasma is turned on. The properties of bandgaps depend on the plasma density and the geometrical parameters of the PPCs structure. The PPCs can perform as dynamical band-stop filter to control the transmission of microwaves within a wide frequency range.

  10. Structural phase transitions and topological defects in ion Coulomb crystals

    SciTech Connect (OSTI)

    Partner, Heather L.; Nigmatullin, Ramil; Burgermeister, Tobias; Keller, Jonas; Pyka, Karsten; Plenio, Martin B.; Retzker, Alex; Zurek, Wojciech Hubert; del Campo, Adolfo; Mehlstaubler, Tanja E.

    2014-11-19

    We use laser-cooled ion Coulomb crystals in the well-controlled environment of a harmonic radiofrequency ion trap to investigate phase transitions and defect formation. Topological defects in ion Coulomb crystals (kinks) have been recently proposed for studies of nonlinear physics with solitons and as carriers of quantum information. Defects form when a symmetry breaking phase transition is crossed non-adiabatically. For a second order phase transition, the Kibble-Zurek mechanism predicts that the formation of these defects follows a power law scaling in the rate of the transition. We demonstrate a scaling of defect density and describe kink dynamics and stability. We further discuss the implementation of mass defects and electric fields as first steps toward controlled kink preparation and manipulation.

  11. Large Flow Birefringence of Nematogenic Bent-Core Liquid Crystals

    SciTech Connect (OSTI)

    Bailey, C.; Fodor-Csorba, K; Verduzco, R; Gleeson, J; Sprunt, S; Jakli, A

    2009-01-01

    We have found that bent-core liquid crystalline materials show exceptionally large intrinsic flow birefringence in their isotropic liquid phase. This effect is more than 100 times larger than typical values measured for low molecular weight liquid crystals. The specific flow birefringence (i.e., normalized by the flow viscosity) is an order of magnitude larger than in both side-chain polymeric as well as low molecular weight liquid crystals. We propose that this large enhancement for bent-core compounds may be attributed to nanoscale smecticlike clusters that persist above the nematic-isotropic transition temperature, and shear align under shear flow; however, this mechanism has not yet been definitively confirmed.

  12. Crystal Collimation Studies at the Tevatron (T-980)

    SciTech Connect (OSTI)

    Mokhov, N.V.; Annala, G.E.; Apyan, A.; Carrigan, R.A.; Drozhdin, A.I.; Johnson, T.R.; Legan, A.M.; Reilly, R.E.; Shiltsev, V.; Still, D.A.; Tesarek, R.J.; /Fermilab /Brookhaven /CERN /Chicago U. /Serpukhov, IHEP /INFN, Ferrara /Insubria U., Como /St. Petersburg, INP

    2009-04-01

    Bent-crystal channeling is a technique with a potential to increase beam-halo collimation efficiency in high-energy colliders. First measurements at the Tevatron in 2005 have shown that using a thin silicon crystal to deflect the 1-TeV proton beam halo onto a secondary collimator improves the system performance by reducing the machine impedance, beam losses in the collider detectors and irradiation of the superconducting magnets, all in agreement with simulations. Recent results, obtained with an improved goniometer and enhanced beam diagnostics, are reported here for dedicated beam studies and first full collider stores along with simulation results and plans for substantial enhancement of the T-980 experimental setup.

  13. How a Bent Crystal Could Polarize the Antiprotons

    SciTech Connect (OSTI)

    Ukhanov, Mikhail

    2008-04-30

    Particles scattered off nuclear targets acquire a polarization if the nuclei have a nonzero analyzing power. This effect is enhanced when particles traverse a bent crystal. Such an enhancement under certain assumptions allows one to get a beam polarization of more than 50% after extraction of a primary beam with a bent crystal. Since the equilibrium condition between centrifugal and electrostatic forces during the channeling are identical for protons and antiprotons this gives us a hope that one can observe an antiproton beam channeling at a reasonable efficiency and get it polarized. It is also possible to observe a volume reflection of antiprotons. The detection of beam polarization resulting from channeling would open a window to a completely unexplored physics domain at very small transfer momentum which is hardly if not at all could be reached with other methods.

  14. High-Efficiency Nitride-Based Photonic Crystal Light Sources

    Broader source: Energy.gov [DOE]

    The University of California Santa Barbara (UCSB) is maximizing the efficiency of a white LED by enhancing the external quantum efficiency using photonic crystals to extract light that would normally be confined in a conventional structure. Ultimate efficiency can only be achieved by looking at the internal structure of light. To do this, UCSB is focusing on maximizing the light extraction efficiency and total light output from light engines driven by Gallium Nitride (GaN)-based LEDs. The challenge is to engineer large overlap (interaction) between modes and photonic crystals. The project is focused on achieving high extraction efficiency in LEDs, controlled directionality of emitted light, integrated design of vertical device structure, and nanoscale patterning of lateral structure.

  15. Los Alamos Discovers Super Efficient Solar Using Perovskite Crystals

    SciTech Connect (OSTI)

    Mohite, Aditya; Nie, Wanyi

    2015-01-29

    State-of-the-art photovoltaics using high-purity, large-area, wafer-scale single-crystalline semiconductors grown by sophisticated, high temperature crystal-growth processes offer promising routes for developing low-cost, solar-based clean global energy solutions for the future. Solar cells composed of the recently discovered material organic-inorganic perovskites offer the efficiency of silicon, yet suffer from a variety of deficiencies limiting the commercial viability of perovskite photovoltaic technology. In research to appear in Science, Los Alamos National Laboratory researchers reveal a new solution-based hot-casting technique that eliminates these limitations, one that allows for the growth of high-quality, large-area, millimeter-scale perovskite crystals and demonstrates that highly efficient and reproducible solar cells with reduced trap assisted recombination can be realized.

  16. Method to fabricate a tilted logpile photonic crystal

    DOE Patents [OSTI]

    Williams, John D. (Albuquerque, NM); Sweatt, William C. (Albuquerque, NM)

    2010-10-26

    A method to fabricate a tilted logpile photonic crystal requires only two lithographic exposures and does not require mask repositioning between exposures. The mask and photoresist-coated substrate are spaced a fixed and constant distance apart using a spacer and the stack is clamped together. The stack is then tilted at a crystallographic symmetry angle (e.g., 45 degrees) relative to the X-ray beam and rotated about the surface normal until the mask is aligned with the X-ray beam. The stack is then rotated in plane by a small stitching angle and exposed to the X-ray beam to pattern the first half of the structure. The stack is then rotated by 180.degree. about the normal and a second exposure patterns the remaining half of the structure. The method can use commercially available DXRL scanner technology and LIGA processes to fabricate large-area, high-quality tilted logpile photonic crystals.

  17. Readout system for multi-crystal gamma cameras

    DOE Patents [OSTI]

    Derenzo, Stephen E. (Pinole, CA)

    1987-01-01

    A radioisotope camera (10) having an array (12) of scintillation crystals (13) arranged in N rows and M columns and adapted to be struck by gamma-rays from a subject, a separate solid state photodetector (15 ) optically coupled to each crystal (13), and N+M amplifiers (24) connected to the photodetectors (15) to distinguish the particular row and column of an activated photodetector. One of the anode or cathode leads (33 or 34) of each photodetector (15) is coupled to the row amplifier (24) associated with the row containing that photodetector while the other of the two leads (34 or 33) is coupled to the column amplifier (24) associated with the column containing that photodetector.

  18. Electrically tuned photoluminescence in large pitch cholesteric liquid crystal

    SciTech Connect (OSTI)

    Middha, Manju Kumar, Rishi Raina, K. K.

    2014-04-24

    Cholesteric liquid crystals are known as 1-D photonic band gap materials due to their periodic helical supramolecular structure and larger birefringence. Depending upon the helical twisted pitch length, they give the characteristic contrast due to selective Bragg reflections when viewed through the polarizing optical microscope and hence affect the electro-optic properties. So the optimization of chiral dopant concentration in nematic liquid crystal leads to control the transmission of polarized light through the microscope. Hence transmission based polarizing optical microscope is used for the characterization of helical pitch length in the optical texture. The unwinding of helical pitch was observed with the application of electric field which affects the intensity of photoluminescence.

  19. Process and apparatus for making oriented crystal layers

    DOE Patents [OSTI]

    Springer, Robert W.

    2002-01-01

    Thin films of single crystal-like materials are made by using flow-through ion beam deposition during specific substrate rotation around an axis in a clocking action. The substrate is quickly rotated to a selected deposition position, paused in the deposition position for ionized material to be deposited, then quickly rotated to the next selected deposition position. The clocking motion can be achieved by use of a lobed cam on the spindle with which the substrate is rotated or by stopping and starting a stepper motor at long and short intervals. Other symmetries can be programmed into the process, allowing virtually any oriented inorganic crystal to be grown on the substrate surface.

  20. Crystallization of lysozyme with (R)-, (S)- and (RS)-2-methyl-2, 4-pentanediol

    SciTech Connect (OSTI)

    Stauber, Mark; Jakoncic, Jean; Berger, Jacob; Karp, Jerome M.; Axelbaum, Ariel; Sastow, Dahniel; Buldyrev, Sergey V.; Hrnjez, Bruce J.; Asherie, Neer

    2015-03-01

    Crystallization of lysozyme with (R)-2-methyl-2, 4-pentanediol produces more ordered crystals and a higher resolution protein structure than crystallization with (S)-2-methyl-2, 4-pentanediol. The results suggest that chiral interactions with chiral additives are important in protein crystal formation. Chiral control of crystallization has ample precedent in the small-molecule world, but relatively little is known about the role of chirality in protein crystallization. In this study, lysozyme was crystallized in the presence of the chiral additive 2-methyl-2, 4-pentanediol (MPD) separately using the R and S enantiomers as well as with a racemic RS mixture. Crystals grown with (R)-MPD had the most order and produced the highest resolution protein structures. This result is consistent with the observation that in the crystals grown with (R)-MPD and (RS)-MPD the crystal contacts are made by (R)-MPD, demonstrating that there is preferential interaction between lysozyme and this enantiomer. These findings suggest that chiral interactions are important in protein crystallization.

  1. Method and apparatus for nucleating the crystallization of undercooled materials

    DOE Patents [OSTI]

    Benson, David K. (Golden, CO); Barret, Peter F. (Peterbourgh, CA)

    1989-01-01

    A method of storing and controlling a release of latent heat of transition of a phase-change material is disclosed. The method comprises trapping a crystallite of the material between two solid objects and retaining it there under high pressure by applying a force to press the two solid objects tightly together. A crystallite of the material is exposed to a quantity of the material that is in a supercooled condition to nucleate the crystallization of the supercooled material.

  2. Optical Basicity and Nepheline Crystallization in High Alumina Glasses

    SciTech Connect (OSTI)

    Rodriguez, Carmen P.; McCloy, John S.; Schweiger, M. J.; Crum, Jarrod V.; Winschell, Abigail E.

    2011-02-25

    The purpose of this study was to find compositions that increase waste loading of high-alumina wastes beyond what is currently acceptable while avoiding crystallization of nepheline (NaAlSiO4) on slow cooling. Nepheline crystallization has been shown to have a large impact on the chemical durability of high-level waste glasses. It was hypothesized that there would be some composition regions where high-alumina would not result in nepheline crystal production, compositions not currently allowed by the nepheline discriminator. Optical basicity (OB) and the nepheline discriminator (ND) are two ways of describing a given complex glass composition. This report presents the theoretical and experimental basis for these models. They are being studied together in a quadrant system as metrics to explore nepheline crystallization and chemical durability as a function of waste glass composition. These metrics were calculated for glasses with existing data and also for theoretical glasses to explore nepheline formation in Quadrant IV (passes OB metric but fails ND metric), where glasses are presumed to have good chemical durability. Several of these compositions were chosen, and glasses were made to fill poorly represented regions in Quadrant IV. To evaluate nepheline formation and chemical durability of these glasses, quantitative X-ray diffraction (XRD) analysis and the Product Consistency Test were conducted. A large amount of quantitative XRD data is collected here, both from new glasses and from glasses of previous studies that had not previously performed quantitative XRD on the phase assemblage. Appendix A critically discusses a large dataset to be considered for future quantitative studies on nepheline formation in glass. Appendix B provides a theoretical justification for choice of the oxide coefficients used to compute the OB criterion for nepheline formation.

  3. The Biological Implications of the PP2A Crystal Structure

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

    The Biological Implications of the PP2A Crystal Structure Print Phosphatases, enzymes that remove a phosphate group from amino-acid substrates, can be subdivided according to their substrate specificity. Myriad evidence has demonstrated that protein phosphatase 2A (PP2A), a family of serine/threonine-specific (Ser/Thr) phosphatases, regulates many, if not most, aspects of cellular activities and is a critical tumor suppressor. A team at the University of Washington recently determined the first

  4. Influence of Crystal Expansion/Contraction on Zeolite Membrane Permeation

    SciTech Connect (OSTI)

    Sorenson, Stephanie G; Payzant, E Andrew; Noble, Richard D; Falconer, John L.

    2010-01-01

    X-ray diffraction was used to measure the unit cell parameters of B-ZSM-5, SAPO-34, and NaA zeolite powders as a function of adsorbate loading at 303 K, and in one case, at elevated temperatures. Most adsorbates expanded the zeolite crystals below saturation loading at 303 K: n-hexane and SF6 in B-ZSM-5, methanol and CO2 in SAPO-34, and methanol in NaA zeolite. As the loadings increased, the crystals expanded more. Changes in the unit cell volumes of B-ZSM-5 and SAPO-34 zeolite powders correlated with changes in permeation through zeolite membranes defects. When the zeolite crystals expanded or contracted upon adsorption, the defect sizes decreased or increased. In B-ZSM-5 membranes, the fluxes through defects decreased dramatically when n-hexane or SF6 adsorbed. In contrast, i-butane adsorption at 303 K contracted B-ZSM-5 crystals at low loadings and expanded them at higher loadings. Correspondingly, the flux through B-ZSM-5 membrane defects increased at low i-butane loadings and decreased at high loading because the defects increased in size at low loading and decreased at high loadings. At 398 K and 473 K, n-hexane expanded the B-ZSM-5 unit cell more as the temperature increased from 303 to 473 K. The silicalite-1 and B-ZSM-5 unit cell volumes expanded similarly upon n-hexane adsorption at 303 K; boron substitution had little effect on volume expansion.

  5. The Biological Implications of the PP2A Crystal Structure

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

    The Biological Implications of the PP2A Crystal Structure Print Phosphatases, enzymes that remove a phosphate group from amino-acid substrates, can be subdivided according to their substrate specificity. Myriad evidence has demonstrated that protein phosphatase 2A (PP2A), a family of serine/threonine-specific (Ser/Thr) phosphatases, regulates many, if not most, aspects of cellular activities and is a critical tumor suppressor. A team at the University of Washington recently determined the first

  6. The Biological Implications of the PP2A Crystal Structure

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

    The Biological Implications of the PP2A Crystal Structure Print Phosphatases, enzymes that remove a phosphate group from amino-acid substrates, can be subdivided according to their substrate specificity. Myriad evidence has demonstrated that protein phosphatase 2A (PP2A), a family of serine/threonine-specific (Ser/Thr) phosphatases, regulates many, if not most, aspects of cellular activities and is a critical tumor suppressor. A team at the University of Washington recently determined the first

  7. The Biological Implications of the PP2A Crystal Structure

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

    The Biological Implications of the PP2A Crystal Structure Print Phosphatases, enzymes that remove a phosphate group from amino-acid substrates, can be subdivided according to their substrate specificity. Myriad evidence has demonstrated that protein phosphatase 2A (PP2A), a family of serine/threonine-specific (Ser/Thr) phosphatases, regulates many, if not most, aspects of cellular activities and is a critical tumor suppressor. A team at the University of Washington recently determined the first

  8. New Crystal Structures Lift Fog around Protein Folding

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

    New Crystal Structures Lift Fog around Protein Folding Print Nature's proteins set a high bar for nanotechnology. Macromolecules forged from peptide chains of amino acids, these biomolecular nanomachines must first be folded into a dazzling variety of shapes and forms before they can perform the multitude of functions fundamental to life. However, the mechanisms behind the protein-folding process have remained a foggy mystery. Now the fog is lifting: a team of researchers from Berkeley Lab,

  9. New Crystal Structures Lift Fog around Protein Folding

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

    New Crystal Structures Lift Fog around Protein Folding Print Nature's proteins set a high bar for nanotechnology. Macromolecules forged from peptide chains of amino acids, these biomolecular nanomachines must first be folded into a dazzling variety of shapes and forms before they can perform the multitude of functions fundamental to life. However, the mechanisms behind the protein-folding process have remained a foggy mystery. Now the fog is lifting: a team of researchers from Berkeley Lab,

  10. New Crystal Structures Lift Fog around Protein Folding

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

    New Crystal Structures Lift Fog around Protein Folding Print Nature's proteins set a high bar for nanotechnology. Macromolecules forged from peptide chains of amino acids, these biomolecular nanomachines must first be folded into a dazzling variety of shapes and forms before they can perform the multitude of functions fundamental to life. However, the mechanisms behind the protein-folding process have remained a foggy mystery. Now the fog is lifting: a team of researchers from Berkeley Lab,

  11. Invariant patterns in crystal lattices: Implications for protein folding algorithms

    SciTech Connect (OSTI)

    Hart, W.E.; Istrail, S.

    1995-12-11

    Crystal lattices are infinite periodic graphs that occur naturally in a variety of geometries and which are of fundamental importance in polymer science. Discrete models of protein folding use crystal lattices to define the space of protein conformations. Because various crystal lattices provide discretizations of the same physical phenomenon, it is reasonable to expect that there will exist ``invariants`` across lattices that define fundamental properties of protein folding process; an invariant defines a property that transcends particular lattice formulations. This paper identifies two classes of invariants, defined in terms of sublattices that are related to the design of algorithms for the structure prediction problem. The first class of invariants is, used to define a master approximation algorithm for which provable performance guarantees exist. This algorithm can be applied to generalizations of the hydrophobic-hydrophilic model that have lattices other than the cubic lattice, including most of the crystal lattices commonly used in protein folding lattice models. The second class of invariants applies to a related lattice model. Using these invariants, we show that for this model the structure prediction problem is intractable across a variety of three-dimensional lattices. It`` turns out that these two classes of invariants are respectively sublattices of the two- and three-dimensional square lattice. As the square lattices are the standard lattices used in empirical protein folding` studies, our results provide a rigorous confirmation of the ability of these lattices to provide insight into biological phenomenon. Our results are the first in the literature that identify algorithmic paradigms for the protein structure prediction problem which transcend particular lattice formulations.

  12. FRACTIONAL CRYSTALLIZATION FLOWSHEET TESTS WITH ACTUAL TANK WASTE

    SciTech Connect (OSTI)

    HERTING, D.L.

    2007-04-13

    Laboratory-scale flowsheet tests of the fractional crystallization process were conducted with actual tank waste samples in a hot cell at the 2224 Laboratory. The process is designed to separate medium-curie liquid waste into a low-curie stream for feeding to supplemental treatment and a high-curie stream for double-shell tank storage. Separations criteria (for Cesium-137 sulfate and sodium) were exceeded in all three of the flowsheet tests that were performed.

  13. FRACTIONAL CRYSTALLIZATION LABORATORY TESTING WITH INTERIM PRETREATMENT SYSTEM FEEDS

    SciTech Connect (OSTI)

    HERTING DL

    2008-09-17

    The fractional crystallization process was developed as a pretreatment method for saltcake waste retrieved from Hanford single-shell tanks (SST). The process separates the retrieved SST waste into a high-level waste stream containing the bulk of the radionuclides and a low-activity waste stream containing the bulk of the nonradioactive sodium salts. The Interim Pretreatment System project shifted the focus on pretreatment planning from SST waste to double-shell tank waste.

  14. FRACTIONAL CRYSTALLIZATION FLOWSHEET TESTS WITH ACTUAL TANK WASTE

    SciTech Connect (OSTI)

    HERTING, D.L.

    2006-10-18

    Laboratory-scale flowsheet tests of the fractional crystallization process were conducted with actual tank waste samples in a hot cell at the 222-S Laboratory. The process is designed to separate medium-curie liquid waste into a low-curie stream for feeding to supplemental treatment and a high-curie stream for double-shell tank storage. Separations criteria (for Cs-137 sulfate, and sodium) were exceeded in all three of the flowsheet tests that were performed.

  15. New Crystal Structures Lift Fog around Protein Folding

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

    New Crystal Structures Lift Fog around Protein Folding Print Nature's proteins set a high bar for nanotechnology. Macromolecules forged from peptide chains of amino acids, these biomolecular nanomachines must first be folded into a dazzling variety of shapes and forms before they can perform the multitude of functions fundamental to life. However, the mechanisms behind the protein-folding process have remained a foggy mystery. Now the fog is lifting: a team of researchers from Berkeley Lab,

  16. Crystal Structure and Functional Analysis Identify Evolutionary Secret of

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

    SerRS in Vascular Development | Stanford Synchrotron Radiation Lightsource Crystal Structure and Functional Analysis Identify Evolutionary Secret of SerRS in Vascular Development Wednesday, July 31, 2013 Aminoacyl-tRNA synthetases (aaRS) have been essential enzymes for protein synthesis throughout evolution. As the tree of life was ascended, tRNA synthetases added new domains, which are generally dispensable for aminoacylation, in a progressive and accretive manner. The acquisitions were

  17. Crystal Structure of Cascade | Stanford Synchrotron Radiation Lightsource

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

    Crystal Structure of Cascade Friday, January 30, 2015 Immune pathways protect all organisms from infection by genetic invaders such as viruses. It was recently discovered that prokaryotes protect against invasion by bacteriophages via an RNA based adaptive immune system, called the CRISPR system (1, 2). By acting as a barrier to the exchange of genetic information, a major route for the acquisition of antibiotic-resistance and virulence factors, the CRISPR system modulates the evolution of

  18. Crystal Structure of a Protein Kinase A Complex

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

    Crystal Structure of a Protein Kinase A Complex Print Protein kinase A (PKA) is an enzyme that regulates processes as diverse as growth, memory, and metabolism. In its unactivated state, PKA exists as a tetrameric complex of two catalytic subunits and a regulatory subunit dimer, but when the intracellular signaling molecule cyclic adenosine monophosphate (cAMP) binds to the regulatory subunit, it facilitates dissociation and activation of the catalytic subunits. While separate structures of

  19. Crystal Structure of a Protein Kinase A Complex

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

    Crystal Structure of a Protein Kinase A Complex Print Protein kinase A (PKA) is an enzyme that regulates processes as diverse as growth, memory, and metabolism. In its unactivated state, PKA exists as a tetrameric complex of two catalytic subunits and a regulatory subunit dimer, but when the intracellular signaling molecule cyclic adenosine monophosphate (cAMP) binds to the regulatory subunit, it facilitates dissociation and activation of the catalytic subunits. While separate structures of

  20. Crystal Structure of a Protein Kinase A Complex

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

    Crystal Structure of a Protein Kinase A Complex Print Protein kinase A (PKA) is an enzyme that regulates processes as diverse as growth, memory, and metabolism. In its unactivated state, PKA exists as a tetrameric complex of two catalytic subunits and a regulatory subunit dimer, but when the intracellular signaling molecule cyclic adenosine monophosphate (cAMP) binds to the regulatory subunit, it facilitates dissociation and activation of the catalytic subunits. While separate structures of