National Library of Energy BETA

Sample records for tiny crystals glow

  1. New family of tiny crystals glow bright in LED lights | ornl...

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

    Minuscule crystals that glow different colors may be the missing ingredient for white LED lighting that illuminates homes and offices as effectively as natural sunlight....

  2. New Family of Tiny Crystals Glow Bright in LED Lights | Advanced...

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

    crystals that glow different colors may be the missing ingredient for white light-emitting diode (LED) lighting that illuminates homes and offices as effectively as natural...

  3. Learning Tiny Theories Tim Menzies

    E-Print Network [OSTI]

    Menzies, Tim

    Learning Tiny Theories Tim Menzies , Rajesh Gunnalan , Kalaivani Appukutty , Amarnath Srinivasan Engineering, University of British Columbia, Canada {gunnalan|avani|amarnath}@csee

  4. Powerful glow discharge excilamp

    DOE Patents [OSTI]

    Tarasenko, Victor F. (Tomsk, RU); Panchenko, Aleksey N. (Tomsk, RU); Skakun, Victor S. (Tomsk, RU); Sosnin, Edward A. (Tomsk, RU); Wang, Francis T. (Danville, CA); Myers, Booth R. (Livermore, CA); Adamson, Martyn G. (Danville, CA)

    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.

  5. RPPL, University of Washington Glow Discharge Cleaning

    E-Print Network [OSTI]

    Washington at Seattle, University of

    of Glow RPPL, University of Washington Bulk metal of vacuum chamber wall Oxide impurity layer water and hydrocarbon impurity layer Schematic of Typical Vacuum Chamber Wall and Impurity Layers + Ion from glow particles - can lead to runaway erosion and contamination · Glow used on TEXTOR, JET, DIII-D, TFTR, ASDEX

  6. 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.

  7. 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...

  8. 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...

  9. 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.

  10. Teeny tiny windmills could recharge phones Share it now!

    E-Print Network [OSTI]

    Chiao, Jung-Chih

    Teeny tiny windmills could recharge phones Green Tech Share it now! 0 One of the tiny windmills. Portfolio Markets Trending Stories Trending Stocks Sector Chat Page 1 of 6Teeny tiny windmills could recharge phones | VantageWire 2/1/2014http://www.vantagewire.com/2014/01/teeny-tiny-windmills

  11. 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.

  12. Probiotic Bacteria Induce a ‘Glow of Health’

    E-Print Network [OSTI]

    Levkovich, Tatiana

    Radiant skin and hair are universally recognized as indications of good health. However, this ‘glow of health’ display remains poorly understood. We found that feeding of probiotic bacteria to aged mice induced integumentary ...

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

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

    Photo of the Week: 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...

  14. How Long Can Tiny HI Clouds Survive?

    E-Print Network [OSTI]

    Masahiro Nagashima; Shu-ichiro Inutsuka; Hiroshi Koyama

    2006-03-10

    We estimate the evaporation timescale for spherical HI clouds consisting of the cold neutral medium surrounded by the warm neutral medium. We focus on clouds smaller than 1pc, which corresponds to tiny HI clouds recently discovered by Braun & Kanekar and Stanimirovi{\\'c} & Heiles. By performing one-dimensional spherically symmetric numerical simulations of the two-phase interstellar medium (ISM), we derive the timescales as a function of the cloud size and of pressure of the ambient warm medium. We find that the evaporation timescale of the clouds of 0.01 pc is about 1Myr with standard ISM pressure, $p/k_{B}\\sim 10^{3.5}$ K cm$^{-3}$, and for clouds larger than about 0.1 pc it depends strongly on the pressure. In high pressure cases, there exists a critical radius for clouds growing as a function of pressure, but the minimum critical size is $\\sim$ 0.03 pc for a standard environment. If tiny HI clouds exist ubiquitously, our analysis suggests two implications: tiny HI clouds are formed continuously with the timescale of 1Myr, or the ambient pressure around the clouds is much higher than the standard ISM pressure. We also find that the results agree well with those obtained by assuming quasi-steady state evolution. The cloud-size dependence of the timescale is well explained by an analytic approximate formula derived by Nagashima, Koyama & Inutsuka. We also compare it with the evaporation rate given by McKee & Cowie.

  15. Light in tiny holes & T. W. Ebbesen1

    E-Print Network [OSTI]

    Turro, Nicholas J.

    REVIEWS Light in tiny holes C. Genet1 & T. W. Ebbesen1 The presence of tiny holes in an opaque metal film, with sizes smaller than the wavelength of incident light, leads to a wide variety of unexpected optical properties such as strongly enhanced transmission of light through the holes

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

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

    combustion p-20ramond.pdf More Documents & Publications Glow Plug Integrated Piezo-Ceramic Combustion Sensor for Diesel Engines Diesel Combustion Control with Closed-Loop...

  17. NSTX Filament Preionization And Glow Discharge Cleaning Systems

    E-Print Network [OSTI]

    NSTX Filament Preionization And Glow Discharge Cleaning Systems H. W. Kugel, W. Blanchard, G. D filament preionization system that allowed D 2 and He Glow Discharge breakdowns at the actual operating pressure, voltage and current. The biased filament system was also operated continuously during ohmic

  18. NSTX Filament Preionization And Glow Discharge Cleaning Systems

    E-Print Network [OSTI]

    NSTX Filament Preionization And Glow Discharge Cleaning Systems H. W. Kugel, W. Blanchard, G. D filament preionization system that allowed D2 and He Glow Discharge breakdowns at the actual operating pressure, voltage and current. The biased filament system was also operated continuously during ohmic

  19. 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.

  20. Glow discharge based device for solving mazes

    SciTech Connect (OSTI)

    Dubinov, Alexander E., E-mail: dubinov-ae@yandex.ru; Mironenko, Maxim S.; Selemir, Victor D. [Russian Federal Nuclear Center ? All-Russian Scientific and Research Institute of Experimental Physics (RFNC-VNIIEF), Sarov, Nizhni Novgorod region 607188 (Russian Federation); Sarov Institute of Physics and Technology (SarFTI) of National Research Nuclear University “MEPhI,” Sarov, Nizhni Novgorod region 607188 (Russian Federation); Maksimov, Artem N.; Pylayev, Nikolay A. [Russian Federal Nuclear Center ? All-Russian Scientific and Research Institute of Experimental Physics (RFNC-VNIIEF), Sarov, Nizhni Novgorod region 607188 (Russian Federation)

    2014-09-15

    A glow discharge based device for solving mazes has been designed and tested. The device consists of a gas discharge chamber and maze-transformer of radial-azimuth type. It allows changing of the maze pattern in a short period of time (within several minutes). The device has been tested with low pressure air. Once switched on, a glow discharge has been shown to find the shortest way through the maze from the very first attempt, even if there is a section with potential barrier for electrons on the way. It has been found that ionization waves (striations) can be excited in the maze along the length of the plasma channel. The dependancy of discharge voltage on the length of the optimal path through the maze has been measured. A reduction in discharge voltage with one or two potential barriers present has been found and explained. The dependency of the magnitude of discharge ignition voltage on the length of the optimal path through the maze has been measured. The reduction of the ignition voltage with the presence of one or two potential barriers has been observed and explained.

  1. An Innovative Pressure Sensor Glow Plug Offers Improved Diesel Engine Closed-loop Control

    Broader source: Energy.gov [DOE]

    Describes glow plug with integrated pressure sensor for closed-loop control of diesel engine combustion

  2. TiNi shape memory alloy thin films for microactuator application

    E-Print Network [OSTI]

    Fu, Yongqing

    TiNi films were prepared by co-sputtering TiNi target and a separate Ti target. Crystalline structure and phase transformation behaviors of TiNi films were investigated. Results showed that TiNi films had fine grain size ...

  3. Entrainment by Spatiotemporal Chaos in Glow Discharge-Semiconductor Systems

    E-Print Network [OSTI]

    Marat Akhmet; Ismail Rafatov; Mehmet Onur Fen

    2014-06-15

    Entrainment of limit cycles by chaos [1] is discovered numerically through specially designed unidirectional coupling of two glow discharge-semiconductor systems. By utilizing the auxiliary system approach [2], 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 [3].

  4. 2/24/2014 Using TinyWindmills To Power Portable Electronics http://searchforthegood.com/using-tiny-windmills-to-power-portable-electronics/ 1/4

    E-Print Network [OSTI]

    Chiao, Jung-Chih

    Power Published on Jan 20th, 2014 by Nathan 0 Cellphones powered by little micro-windmills covering2/24/2014 Using TinyWindmills To Power Portable Electronics http://searchforthegood.com/using-tiny-windmills-to-power-portable-electronics/ 1/4 Using Tiny Windmills To Power Portable Electronics JANUARY 20, 2014 BY LEAVE A COMMENT Clean

  5. Interface Contracts for TinyOS Will Archer

    E-Print Network [OSTI]

    Regehr, John

    Interface Contracts for TinyOS Will Archer School of Computing University of Utah warcher and enforce component interface contracts. Due to the ex- tensive reuse of the most common interfaces, implementing con- tracts for a small number of frequently reused interfaces permitted us to extensively check

  6. TinyDDS: An Interoperable and Configurable Publish/Subscribe

    E-Print Network [OSTI]

    Suzuki, Jun

    (DDS) specification. Moreover, TinyDDS provides a pluggable framework that allows WSN applications/subscribe WSN applications. INTRODUCTION Wireless sensor networks (WSNs) have been used to detect events and and construct complex natural/physical systems (Estrin et al., 1999). A WSN application requires per

  7. UT Arlington > Features Building tiny robots to deliver medicine

    E-Print Network [OSTI]

    Chiao, Jung-Chih

    UT Arlington > Features Building tiny robots to deliver medicine Coming from a family of doctors systems. "I've always been interested in medicine and medical-related fields," she says. So much so in India, Rao had only two options: dental school or engineering. Considering her interest in medicine, she

  8. Glow discharge plasma deposited hexauoropropylene lms: surface chemistry and interfacial materials properties

    E-Print Network [OSTI]

    Glow discharge plasma deposited hexa¯uoropropylene ®lms: surface chemistry and interfacial; accepted 10 November 1998 Abstract Fluoropolymer ®lms prepared by radio frequency glow discharge (RF, HFP) ®lms is shown to confer surface functional group presentation that promotes high protein

  9. 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, 4528–4535 (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. Šija?i? U. Ebert, and I. Rafatov, Phys. Rev. E 70, 056220 (2004).].

  10. 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.

  11. Stabilization of a cold cathode electron beam glow discharge for surface treatment

    E-Print Network [OSTI]

    Rocca, Jorge J.

    Stabilization of a cold cathode electron beam glow discharge for surface treatment N. Mingolo and C that the reproducibility of electron beam pulses generated by a high power, cold cathode glow discharge is greatly improved cathode high voltage glow discharges can generate powerful electron beams for materials processing.1

  12. 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.

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

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE: Alternative Fuels DataEnergy Webinar:IAboutReubenPressElectrical Safety-Electrofuels: Tiny

  14. First Impressions in a Glowing Host-Microbe Partnership

    E-Print Network [OSTI]

    McFall-Ngai, Margaret

    #12;First Impressions in a Glowing Host-Microbe Partnership Jennifer J. Wernegreen1,* 1Nicholas://dx.doi.org/10.1016/j.chom.2013.07.015 Despite the clear significance of beneficial animal-microbe associations & Microbe, Kremer et al. (2013) reveal that first contact within the squid-vibrio symbiosis triggers

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

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With U.S.Week DayDr.Theories81 to 1990 Timeline of Events:10PhotoTiny

  16. 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.

  17. HoustonChronicle.com -Tiny honor a big deal for algae scientist HoustonChronicle.

    E-Print Network [OSTI]

    Jeong, Hae Jin

    HoustonChronicle.com - Tiny honor a big deal for algae scientist HoustonChronicle. com Section-mail this story June 18, 2005, 5:48PM Tiny honor a big deal for algae scientist By DAVID A. FAHRENTHOLD Washington Post Sometimes, algae can be the highest form of flattery. ADVERTISEMENTSo it was for Diane K. Stoecker

  18. Tiny camera could aid in robotics, night vision Monday, January 17, 2011

    E-Print Network [OSTI]

    Rogers, John A.

    Tiny camera could aid in robotics, night vision Monday, January 17, 2011 Researchers from night-vision surveillance, robotic vision, endoscopic imaging, and consumer electronics. "We were on this article! 0 COMMENTS Page 1 of 1Tiny camera could aid in robotics, night vision | R&D Mag 1/19/2011http

  19. 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

  20. 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

  1. 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.

  2. Nonlinear Dust Acoustic Waves, Shocks and Stationary Structures in a DC Glow Discharge Dusty Plasma

    E-Print Network [OSTI]

    Merlino, Robert L.

    Nonlinear Dust Acoustic Waves, Shocks and Stationary Structures in a DC Glow Discharge Dusty Plasma drifting dusty plasmas and temporal dust acoustic wave growth Phys. Plasmas 18, 113706 (2011) Modulational;Nonlinear Dust Acoustic Waves, Shocks and Stationary Structures in a DC Glow Discharge Dusty Plasma Robert L

  3. The influence of vacuum annealing, glow discharge and electropolishing on the topography of stainless steel sheet metal

    E-Print Network [OSTI]

    Unterlerchner, W

    1977-01-01

    The influence of vacuum annealing, glow discharge and electropolishing on the topography of stainless steel sheet metal

  4. 2/1/2014 TinyMicro-Robotic Windmill Recharges Phone Batteries -Paperblog http://en.paperblog.com/tiny-micro-robotic-windmill-recharges-phone-batteries-769045/ 1/5

    E-Print Network [OSTI]

    Chiao, Jung-Chih

    2/1/2014 TinyMicro-Robotic Windmill Recharges Phone Batteries - Paperblog http://en.paperblog.com/tiny-micro-robotic-windmill-recharges-phone-batteries-769045/ 1/5 HOME > SOCIETY Tiny Micro-Robotic Windmill Recharges Phone Batteries Posted on the 14 January 2014 by Dailyfusion One of Rao's micro-windmills is placed here on a penny. (Credit: University

  5. 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.

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

    Office of Science (SC) Website

    P: (202) 586-5430 06.24.13 "Printing" Tiny Batteries Researchers use sophisticated 3D printing techniques to create batteries the size of a grain of sand. Print Text Size: A A A...

  7. 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.

  8. Building together : tiny house villages for the homeless : a comparative case study

    E-Print Network [OSTI]

    Mingoya, Catherine Ariel

    2015-01-01

    Tiny homes, no larger than a parallel parking spot, are an emerging trend in housing for those uninterested, unwilling or unable to participate in traditional housing markets. Five groups across the United States have ...

  9. 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.

  10. 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.

  11. 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.

  12. 2/1/2014 Financial Press -Breaking Business & Economic News http://financialpress.com/2014/01/21/teeny-tiny-windmills-could-recharge-phones/ 1/6

    E-Print Network [OSTI]

    Chiao, Jung-Chih

    /01/21/teeny-tiny-windmills-could-recharge-phones/ 1/6 Teeny tiny windmills could recharge phones Home » Green Tech » Teeny tiny windmills could recharge phones One of the tiny windmills. (Credit: University of Texas, Arlington) A microscopic windmill could one day provide a portable method of charging devices

  13. 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, Tripura–799 046 (India); Sharma, P. K.; Thakur, A.; Kulkarni, S. V.; Bora, D. [Institute for Plasma Research, Bhat, Gandhinagar, Gujarat–382 428 (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.

  14. Period doubling cascade in glow discharges: Local versus global differential conductivity Danijela D. Sijaci,1

    E-Print Network [OSTI]

    Ebert, Ute

    and energy saving lamps, beamers, flat TV screens, car and street lamps, as well as in various industrial]. In addition to structures familiar from other physical systems, glow discharges continue to exhibit new

  15. 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.

  16. 2/21/2014 Could TinyWindmills ReallyCharge Your Phone? | Ask.com http://theknow.ask.com/could-tiny-windmills-really-charge-your-phone 1/3

    E-Print Network [OSTI]

    Chiao, Jung-Chih

    2/21/2014 Could TinyWindmills ReallyCharge Your Phone? | Ask.com http://theknow.ask.com/could-tiny-windmills-really-charge-your-phone 1/3 More from Jennifer Still By Jennifer Still February 1 7 , 201 4 COULD TINY WINDMILLS REALLY #windmills We've all been there before: you're out and about for the day, and by the time your lunch break

  17. 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.

  18. Tell Barack Obama the Truth The Whole Truth Embers of election night elation will glow longer than any prior election. Glowing even

    E-Print Network [OSTI]

    Hansen, James E.

    global warming to date is smaller than day-to-day weather fluctuations, it has brought global temperatureTell Barack Obama the Truth ­ The Whole Truth Embers of election night elation will glow longer areas. Further warming is "in the pipeline" due to gases already in the air (because of climate system

  19. 2/1/2014 TinyMicro-Robotic Windmill Recharges Phone Batteries | The DailyFusion http://dailyfusion.net/2014/01/tiny-micro-windmill-recharges-phone-batteries-25864/ 1/4

    E-Print Network [OSTI]

    Chiao, Jung-Chih

    2/1/2014 TinyMicro-Robotic Windmill Recharges Phone Batteries | The DailyFusion http://dailyfusion.net/2014/01/tiny-micro-windmill-recharges-phone-batteries-25864/ 1/4 Knowledge is Power prev next A UT Arlington research associate and electrical engineering professor have designed a micro-windmill

  20. The corrosion behavior and hemocompatibility of TiNi alloys coated with DLC by plasma based ion implantation

    E-Print Network [OSTI]

    Zheng, Yufeng

    The corrosion behavior and hemocompatibility of TiNi alloys coated with DLC by plasma based ion successfully deposited on Ti­50.8 at.% Ni alloys using plasma based ion implantation (PBII) technique on the surface modification of TiNi alloys, including ion implan- tation, multi arc ion-plating as well as Ti

  1. Surface characteristics and corrosion resistance properties of TiNi shape memory alloy coated with Ta

    E-Print Network [OSTI]

    Zheng, Yufeng

    for electroplated, crimped, or swaged metal bands that can be abrasive, loosen, crack, or fall off. For coatingSurface characteristics and corrosion resistance properties of TiNi shape memory alloy coated coated with tantalum by the arc ion plating method with the aim to improve their radiopacity. Surface

  2. Wave goodbye to flat batteries: tiny windmills could power smartphones on the go

    E-Print Network [OSTI]

    Chiao, Jung-Chih

    Wave goodbye to flat batteries: tiny windmills could power smartphones on the go by Matthew Jarvis associate and electrical engineering professor, designed and built the `micro-windmills' as part of a brainstorm commissioned by a Taiwanese firm. "The company was quite surprised with the micro-windmill idea

  3. The Big Picture Multisets Sets One Last Word A Tiny Introduction to Group Arithmetic

    E-Print Network [OSTI]

    Ponomarenko, Vadim

    The Big Picture Multisets Sets One Last Word A Tiny Introduction to Group Arithmetic past University July 3, 2008 http://www-rohan.sdsu.edu/vadim/arithmetic.pdf #12;The Big Picture Multisets Sets One of S. "Sequence"=Multiset #12;The Big Picture Multisets Sets One Last Word the basic problem Let G

  4. Quasi-localized wavefunctions on magnetized tori and tiny neutrino Yukawa couplings

    E-Print Network [OSTI]

    Keigo Sumita

    2015-09-11

    This paper shows that, a quasi-localization of wavefunctions in toroidal compactifications with magnetic fluxes can lead to a strong suppression for relevant Yukawa couplings, and it is applicable to obtain tiny neutrino masses. Although it is known that magnetic fluxes lead to a Gaussian profile of zero-modes on a torus and that can yield a suppressed coupling in higher-dimensional supersymmetric Yang-Mills (SYM) theories, the largest (diagonal) entry of Yukawa matrices is always of $\\mathcal O(1)$. In this paper, we propose a way to induce an absolutely tiny global factor of Yukawa matrices. In two SYM theories defined in different dimensional spacetime, their bifundamental representations must be localized as a point in some directions. Overlaps of such point-like localized wavefunctions and Gaussian zero-modes give a global factor of Yukawa matrices, and it can be a strong suppression factor or a usual $\\mathcal O(1)$ factor, corresponding to their distance. Our numerical analysis shows that it is possible to obtain a suppression strong enough to realize the tiny neutrino masses without a hard fine-tuning. Furthermore, we propose a concrete model of the tiny neutrino Yukawa couplings in a magnetized SYM system.

  5. 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.

  6. 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.

  7. 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.

  8. Simulation of the shielding of dust particles in low pressure glow Seung J. Choi and Mark J. Kushner

    E-Print Network [OSTI]

    Kushner, Mark

    Simulation of the shielding of dust particles in low pressure glow discharges Seung J. Choi) The dynamics of the shielding of particulates ("dust") in low pressure glow discharges have been investigated sections represented by the geometrical obscuration of the charged dust particles and their shield- ing

  9. 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.

  10. 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.

  11. Long range temporal correlation in the chaotic oscillations of a dc glow discharge plasma

    SciTech Connect (OSTI)

    Lahiri, S. [Dinabandhu Mahavidyalaya, Bongaon, North 24 Parganas, Kolkata 743235 (India); Roychowdhury, D. [Techno India, EM4/1 Sector V, Salt Lake, Kolkata 700091 (India); Sekar Iyengar, A. N. [Plasma Physics Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India)

    2012-08-15

    Long range temporal correlations in the fluctuations of the plasma floating potentials (measured using a Langmuir probe) are investigated in a dc glow discharge plasma. Keeping the neutral pressure constant, the discharge voltage was varied and at the formation of the plasma, quasi periodic oscillations were excited and on further increase of the discharge voltage they became chaotic (irregular) beyond a threshold voltage. We compared the Lyapunov exponent with the Hurst exponent obtained from R/S statistics which showed an opposite behaviour at the transition point. These results are perhaps new since we have not come across such comparative analysis for chaotic oscillations in a glow discharge plasma before.

  12. Parametric investigation of nonlinear fluctuations in a dc glow discharge plasma

    SciTech Connect (OSTI)

    Nurujjaman, Md.; Narayanan, Ramesh; Sekar Iyengar, A. N. [Plasma Physics Division, Saha Institute of Nuclear Physics, 1/AF, Bidhannagar, Kolkata, 700064 (India)

    2007-12-15

    Glow discharge plasmas exhibit various types of self-excited oscillations for different initial conditions like discharge voltages and filling pressures. The behavior of such oscillations associated with the anode glow has been investigated using nonlinear techniques like correlation dimension, largest Lyapunov exponent, etc. It is seen that these oscillations go to an ordered state from a chaotic state with an increase in input energy, i.e., with discharge voltages implying occurrence of inverse bifurcations. These results are different from the other observations wherein the fluctuations have been observed to go from ordered to chaotic state.

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

    SciTech Connect (OSTI)

    Couëdel, 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.

  14. Technology Review: Tiny Pumps Drive Liquid Circuits http://www.technologyreview.com/articles/rnb_031204.asp 1 of 2 3/27/2004 9:07 PM

    E-Print Network [OSTI]

    Rogers, John A.

    Computing Energy Nanotech Security Software Telecom / Internet Transportation Expanded List TOPICTechnology Review: Tiny Pumps Drive Liquid Circuits http > BIOTECHNOLOGY AND HEALTH CARE > DEVICES Tiny Pumps Drive Liquid Circuits Technology Research News March 12, 2004

  15. Perturbation of the cathode fall in direct-current glow discharges by particulate contamination

    E-Print Network [OSTI]

    Kushner, Mark

    Perturbation of the cathode fall in direct-current glow discharges by particulate contamination July 1991; accepted for publication 19 September 1991) Particulate (or "dust") contamination of plasma by dust contamination. We find that at constant current densities, the plasma responds to the reduction

  16. 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.

  17. Earth's Glow on the Young Moon: A Conjecture on the Lunar Farside Asymmetry

    E-Print Network [OSTI]

    Rhoads, James

    Earth's Glow on the Young Moon: A Conjecture on the Lunar Farside Asymmetry Arpita Roy & Jason of the Moon with the Earth" by Stigmatella aurantiaca Licensed under CC BY-SA 3.0 via Wikimedia Commons File:Tidal_locking_of_the_Moon_with_the_Earth Hypothesis: Moon formed from impact of Mars sized protoplanet, "Theia", with proto-earth Moon formed from

  18. DC Discharge Studies Using PIC-MCC: Unmagnetized Glow Discharge Theory Jeff Hammel & John Verboncoeur

    E-Print Network [OSTI]

    Wurtele, Jonathan

    DC Discharge Studies Using PIC-MCC: Unmagnetized Glow Discharge Theory Jeff Hammel & John Wiley and Sons, Inc., New York, 1994. · Leonard B. Loeb. Fundamental Processes of Electrical Discharge. Verboncoeur, A. B. Langdon, and N. T. Gladd. An object-oriented electromagnetic pic code. Computer Physics

  19. Planetary Nebula Planetary Nebula Planetary Nebula The bright glowing outer layers of gas

    E-Print Network [OSTI]

    Bechtold, Jill

    produced by fusion and in the heat of the explosion are scattered into space. Mass: 3 - 60 SM Star from a red giant star. The explosion occurs when the hydrogen fuel in the core is depleted. Mass: 0.5 - 1.0 SM StarPower Points: 5 The bright glowing outer layers of gas ejected from a red giant star

  20. 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.

  1. 2/1/2014 This Super-TinyWindmill Could SomedayCharge Your Phone | Gizmodo Australia http://www.gizmodo.com.au/2014/01/this-super-tiny-windmill-could-someday-charge-your-phone/ 1/2

    E-Print Network [OSTI]

    Chiao, Jung-Chih

    ://www.gizmodo.com.au/2014/01/this-super-tiny-windmill-could-someday-charge-your-phone/ 1/2 Business & Technology Business's Man With These 65 Life Hacks From Goldman Sachs Stop Overthinking Your Life Ask

  2. 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.

  3. 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.

  4. 2/1/2014 Teenytinywindmills could recharge phones | VantageWire http://www.vantagewire.com/2014/01/teeny-tiny-windmills-could-recharge-phones/ 1/2

    E-Print Network [OSTI]

    Chiao, Jung-Chih

    /01/teeny-tiny-windmills-could-recharge-phones/ 1/2 Teeny tiny windmills could recharge phones Green Tech Share it now! 0 One of the tiny windmills. (Credit: University of Texas, Arlington) A microscopic windmill could one day provide a portable method of charging devices. The tiny machines, just 1

  5. Time series analysis of ionization waves in dc neon glow discharge

    SciTech Connect (OSTI)

    Hassouba, M. A.; Al-Naggar, H. I.; Al-Naggar, N. M.; Wilke, C. [Department of Physics, Faculty of Science, Benha University (Egypt); Institute of Physics, E. M. A. University, Domstrasse 10a, 17489 Greifswald (Germany)

    2006-07-15

    The dynamics of dc neon glow discharge is examined by calculating a Lyapunov exponent spectrum (LES) and correlation dimension (D{sub corr}) from experimental time series. The embedding theory is used to reconstruct an attractor with the delay coordinate method. The analysis refers to periodic, chaotic, and quasi-periodic attractors. The results obtained are confirmed by a comparison with other methods of time series analysis such as the Fourier power spectrum and autocorrelation function. The main object of the present work is the positive column of a dc neon glow discharge. The positive column is an excellent model for the study of a non-linearity plasma system because it is nonisothermal plasma far from equilibrium.

  6. Investigation of complexity dynamics of inverse and normal homoclinic bifurcation in a glow discharge plasma

    SciTech Connect (OSTI)

    Saha, Debajyoti, E-mail: debajyoti.saha@saha.ac.in; Kumar Shaw, Pankaj; Janaki, M. S.; Sekar Iyengar, A. N.; Ghosh, Sabuj; Mitra, Vramori, E-mail: vramorimitra@yahoo.com; Michael Wharton, Alpha [Plasma Physics Division, Saha Institute of Nuclear Physics, 1/AF, Bidhannagar, Kolkata 700064 (India)] [Plasma Physics Division, Saha Institute of Nuclear Physics, 1/AF, Bidhannagar, Kolkata 700064 (India)

    2014-03-15

    Order-chaos-order was observed in the relaxation oscillations of a glow discharge plasma with variation in the discharge voltage. The first transition exhibits an inverse homoclinic bifurcation followed by a homoclinic bifurcation in the second transition. For the two regimes of observations, a detailed analysis of correlation dimension, Lyapunov exponent, and Renyi entropy was carried out to explore the complex dynamics of the system.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. An explanation for the tiny value of the cosmological constant and the low vacuum energy density

    E-Print Network [OSTI]

    Nassif, Cláudio

    2015-01-01

    The paper aims to provide an explanation for the tiny value of the cosmological constant and the low vacuum energy density to represent the dark energy. To accomplish this, we will search for a fundamental principle of symmetry in space-time by means of the elimination of the classical idea of rest, by including an invariant minimum limit of speed in the subatomic world. Such a minimum speed, unattainable by particles, represents a preferred reference frame associated with a background field that breaks down the Lorentz symmetry. The metric of the flat space-time shall include the presence of a uniform vacuum energy density, which leads to a negative pressure at cosmological length scales. Thus, the equation of state for the cosmological constant [$p$(pressure)$=- \\epsilon$ (energy density)] naturally emerges from such a space-time with an energy barrier of a minimum speed. The tiny values of the cosmological constant and the vacuum energy density will be successfully obtained, being in agreement with the obs...

  12. Quasi-localized wavefunctions on magnetized tori and tiny neutrino Yukawa couplings

    E-Print Network [OSTI]

    Sumita, Keigo

    2015-01-01

    This paper shows that, a quasi-localization of wavefunctions in toroidal compactifications with magnetic fluxes can lead to a strong suppression for relevant Yukawa couplings, and it is applicable to obtain tiny neutrino masses. Although it is known that magnetic fluxes lead to a Gaussian profile of zero-modes on a torus and that can yield a suppressed coupling in higher-dimensional supersymmetric Yang-Mills (SYM) theories, the largest (diagonal) entry of Yukawa matrices is always of $\\mathcal O(1)$. In this paper, we propose a way to induce an absolutely tiny global factor of Yukawa matrices. In two SYM theories defined in different dimensional spacetime, their bifundamental representations must be localized as a point in some directions. Overlaps of such point-like localized wavefunctions and Gaussian zero-modes give a global factor of Yukawa matrices, and it can be a strong suppression factor or a usual $\\mathcal O(1)$ factor, corresponding to their distance. Our numerical analysis shows that it is possibl...

  13. An explanation for the tiny value of the cosmological constant and the low vacuum energy density

    E-Print Network [OSTI]

    Cláudio Nassif

    2015-09-28

    The paper aims to provide an explanation for the tiny value of the cosmological constant and the low vacuum energy density to represent the dark energy. To accomplish this, we will search for a fundamental principle of symmetry in space-time by means of the elimination of the classical idea of rest, by including an invariant minimum limit of speed in the subatomic world. Such a minimum speed, unattainable by particles, represents a preferred reference frame associated with a background field that breaks down the Lorentz symmetry. The metric of the flat space-time shall include the presence of a uniform vacuum energy density, which leads to a negative pressure at cosmological length scales. Thus, the equation of state for the cosmological constant [$p$(pressure)$=- \\epsilon$ (energy density)] naturally emerges from such a space-time with an energy barrier of a minimum speed. The tiny values of the cosmological constant and the vacuum energy density will be successfully obtained, being in agreement with the observational results of Perlmutter, Schmidt and Riess.

  14. Evaporation of tiny water aggregation on solid surfaces of different wetting properties

    E-Print Network [OSTI]

    Shen Wang; Yusong Tu; Rongzheng Wan; Haiping Fang

    2012-03-08

    The evaporation of a tiny amount of water on the solid surface with different wettability has been studied by molecular dynamics simulations. We found that, as the surface changed from hydrophobicity to hydrophility, the evaporation speed did not show a monotonically decrease from intuition, but increased first, and then decreased after reached a maximum value. The competition between the number of the water molecules on the water-gas surface from where the water molecules can evaporate and the potential barrier to prevent those water molecules from evaporating results in the unexpected behavior of the evaporation. A theoretical model based on those two factors can fit the simulation data very well. This finding is helpful in understanding the evaporation on the biological surfaces, designing artificial surface of ultra fast water evaporating or preserving water in soil.

  15. 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.

  16. 2/23/2014 Tinywindmills for charging your phone | Forum for the Future https://www.forumforthefuture.org/blog/tiny-windmills-charging-your-phone 1/2

    E-Print Network [OSTI]

    Chiao, Jung-Chih

    2/23/2014 Tinywindmills for charging your phone | Forum for the Future https://www.forumforthefuture.org/blog/tiny-windmills-charging-your-phone 1/2 Home > Blogs > Show All > Tiny windmills for charging your phone Events Masters Course Members area Jobs Media Centre UK USA India Enter keywords Filter Show All Forum Blog Jonathon Porritt Weak

  17. 1/14/14 Teenytinywindmills can recharge phones -Mobile Phone Accessories www.cnet.com.au/teeny-tiny-windmills-can-recharge-phones-339346406.htm 1/5

    E-Print Network [OSTI]

    Chiao, Jung-Chih

    1/14/14 Teenytinywindmills can recharge phones - Mobile Phone Accessories www.cnet.com.au/teeny-tiny-windmills-can-recharge-phones-339346406.htm 1/5 Teeny tiny windmills can recharge phones By Michelle Starr (http. Researchers at the University of Texas, Arlington, have designed a microscopic windmill that, en masse, could

  18. Bacteria with tiny projections can make efficient fuel cells September 7th, 2009 -3:52 pm ICT by ANI -

    E-Print Network [OSTI]

    Lovley, Derek

    Bacteria with tiny projections can make efficient fuel cells September 7th, 2009 - 3:52 pm ICT in fuel cells than bacteria with a smooth surface. The team was led by Professor Derek Lovley from they called KN400 that grew prolifically on the graphite anodes of fuel cells. The bacteria formed a thick

  19. 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.

  20. 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.

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

    DOE Patents [OSTI]

    Duckworth, Douglas C. (Knoxville, TN); Marcus, R. Kenneth (Clemson, SC); Donohue, David L. (Vienna, AT); Lewis, Trousdale A. (Oak Ridge, TN)

    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.

  2. 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.

  3. 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.

  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. 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.

  6. Performance and Economics of Catalytic Glow Plugs and Shields in Direct Injection Natural Gas Engines for the Next Generation Natural Gas Vehicle Program: Final Report

    SciTech Connect (OSTI)

    Mello, J. P.; Bezaire, D.; Sriramulu, S.; Weber, R.

    2003-08-01

    Subcontractor report details work done by TIAX and Westport to test and perform cost analysis for catalytic glow plugs and shields for direct-injection natural gas engines for the Next Generation Natural Gas Vehicle Program.

  7. Non-linear macro evolution of a dc driven micro atmospheric glow discharge

    E-Print Network [OSTI]

    Xu, Shaofeng

    2015-01-01

    We studied the macro evolution of the micro atmospheric glow discharge generated between a micro argon jet into ambient air and static water. The micro discharge behaves similarly to a complex ecosystem. Non-linear behaviors are found for the micro discharge when the water acts as a cathode, different from the discharge when water behaves as an anode. Groups of snapshots of the micro discharge formed at different discharge currents are captured by an intensified charge-coupled device with controlled exposure time, and each group consisted of 256 images taken in succession. Edge detection methods are used to identify the water surface and then the total brightness is defined by adding up the signal counts over the area of the micro discharge. Motions of the water surface at different discharge currents show that the water surface lowers increasingly rapidly when the water acts as a cathode. In contrast, the water surface lowers at a constant speed when the water behaves as an anode. The light curves are simila...

  8. 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.

  9. Junction silicon solar cells made with molecular beam glow discharge bombardment

    SciTech Connect (OSTI)

    Caine, E.J.

    1982-01-01

    The fabrication of silicon PN junction solar cells with molecular implanted emitter regions is described. A simple, economical high current (0.5 mA/cm/sup 2/), low voltage (4-6 kV) glow discharge apparatus without any ion mass separation is used for implantation. The discharge beam is characterized with a current-voltage conduction curve, radial profile of target sheet resistance and operating temperature of implant target. Molecular implantation compounds discussed include: boron trifluoride, trimethyl borate, boron trichloride, trimethyl phosphite, arsenic trifluoride, phosphorus trichloride, phosphorus oxychloride and arsenic trichloride. Annealing is accomplished with a Q-switched ruby laser and with a standard diffusion furnace. Solar cell performance parameters (conversion efficiency, quantum efficiency and junction ideality) are compared with cells conventionally implanted at 30 keV with /sup 11/B and /sup 31/P and cells made with a standard open tube phosphorus oxychloride diffusion. Cell substrate thickness was found to limit short circuit current. Total area simulated AM1 power conversion efficiencies of molecular cells without antireflection coatings or backsurface fields are at best 8.2% as compared to 9.0% for conventional implanted or diffused devices. To achieve optimum performance, laser light had to be incorporated in the molecular implant annealing procedure.

  10. Light Sets Tiny Objects Aquiver --Cho 2005 (712): 2 --sciencenow http://sciencenow.sciencemag.org/cgi/content/full/2005/712/2 1 of 2 7/14/2005 11:55 AM

    E-Print Network [OSTI]

    ://sciencenow.sciencemag.org/cgi/content/full/2005/712/2 1 of 2 7/14/2005 11:55 AM Hum along. Light pressure sets a tiny glass disk vibrating Tiny Objects Aquiver Much as a kid might make a soda bottle shake by blowing across its top and filling it with sound waves, physicists have set a tiny disk of glass vibrating by "whistling" light through it

  11. Etching of UO{sub 2} in NF{sub 3} RF Plasma Glow Discharge

    SciTech Connect (OSTI)

    John M. Veilleux

    1999-08-01

    A series of room temperature, low pressure (10.8 to 40 Pa), low power (25 to 210 W) RF plasma glow discharge experiments with UO{sub 2} were conducted to demonstrate that plasma treatment is a viable method for decontaminating UO{sub 2} from stainless steel substrates. Experiments were conducted using NF{sub 3} gas to decontaminate depleted uranium dioxide from stainless-steel substrates. Depleted UO{sub 2} samples each containing 129.4 Bq were prepared from 100 microliter solutions of uranyl nitrate hexahydrate solution. The amorphous UO{sub 2} in the samples had a relatively low density of 4.8 gm/cm{sub 3}. Counting of the depleted UO{sub 2} on the substrate following plasma immersion was performed using liquid scintillation counting with alpha/beta discrimination due to the presence of confounding beta emitting daughter products, {sup 234}Th and {sup 234}Pa. The alpha emission peak from each sample was integrated using a gaussian and first order polynomial fit to improve quantification. The uncertainties in the experimental measurement of the etched material were estimated at about {+-} 2%. Results demonstrated that UO{sub 2} can be completely removed from stainless-steel substrates after several minutes processing at under 200 W. At 180 W and 32.7 Pa gas pressure, over 99% of all UO{sub 2} in the samples was removed in just 17 minutes. The initial etch rate in the experiments ranged from 0.2 to 7.4 {micro}m/min. Etching increased with the plasma absorbed power and feed gas pressure in the range of 10.8 to 40 Pa. A different pressure effect on UO{sub 2} etching was also noted below 50 W in which etching increased up to a maximum pressure, {approximately}23 Pa, then decreased with further increases in pressure.

  12. 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.

  13. ig research into the tiny world of nanotechnology received a giant boost with the establishment of the Russell Berrie Nanotechnology Institute (RBNI) at the

    E-Print Network [OSTI]

    Rimon, Elon

    B ig research into the tiny world of nanotechnology received a giant boost with the establishment of the Russell Berrie Nanotechnology Institute (RBNI) at the Technion. "The Technion's ranking as a world leader in nanotechnology strongly influenced our decision," said Angelica Berrie, president of the Russell Berrie

  14. Dust acoustic waves in a direct current glow discharge C. Thompson, A. Barkan, N. D'Angelo, and R. L. Merlinoa)

    E-Print Network [OSTI]

    Merlino, Robert L.

    Dust acoustic waves in a direct current glow discharge C. Thompson, A. Barkan, N. D'Angelo, and R Received 25 February 1997; accepted 21 April 1997 An experimental investigation of dust acoustic DA waves electrostatically. The dust acoustic waves were produced by applying a modulation signal 5­40 Hz to the anode

  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. Sweating the small stuff: simulating dwarf galaxies, ultra-faint dwarf galaxies, and their own tiny satellites

    E-Print Network [OSTI]

    Wheeler, Coral; Bullock, James S; Boylan-Kolchin, Michael; Elbert, Oliver; Garrison-Kimmel, Shea; Hopkins, Philip F; Keres, Dusan

    2015-01-01

    We present FIRE/Gizmo hydrodynamic zoom-in simulations of isolated dark matter halos, two each at the mass of classical dwarf galaxies ($M_{\\rm vir} \\simeq 10^{10} M_{\\odot}$) and ultra-faint galaxies ($M_{\\rm vir} \\simeq 10^9 M_{\\odot}$), and with two feedback implementations. The resultant central galaxies lie on an extrapolated abundance matching relation from $M_{\\star} \\simeq 10^6$ to $10^4 M_{\\odot}$ without a break. Every host is filled with subhalos, many of which form stars. Our dwarfs with $M_{\\star} \\simeq 10^6 M_{\\odot}$ each have 1-2 well-resolved satellites with $M_{\\star} = 3-200 \\times 10^3 M_{\\odot}$. Even our isolated ultra-faint galaxies have star-forming subhalos. If this is representative, dwarf galaxies throughout the universe should commonly host tiny satellite galaxies of their own. We combine our results with the ELVIS simulations to show that targeting $\\sim 50~ \\rm kpc$ regions around nearby isolated dwarfs could increase the chances of discovering ultra-faint galaxies by $\\sim 35\\%...

  17. 3/4/2014 These windmills are so tiny, you could fit 10 of them on a grain of rice | Grist http://grist.org/list/these-windmills-are-so-tiny-you-could-fit-10-of-them-on-a-grain-of-rice/ 1/2

    E-Print Network [OSTI]

    Chiao, Jung-Chih

    -Arlington The gospel about windmills is that bigger is better. And there are advantages to building bigger windmills-Arlington went the other way, and made micro windmills so small they're "a tenth the size of a grain of rice," Raw Story says. When a windmill is that tiny, wind comes easy -- you could just wave your hand over

  18. 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)

  19. 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.

  20. Tiny Technology... Huge Potential

    E-Print Network [OSTI]

    Akin, Tayfun

    , Germany OSAMU TABATA, Kyoto University, Kyoto, Japan Save 10% with Your Continuation Order www either on a continuation order basis or individually. An attractive series price is available, Switzerland Gary K. Fedder, Department of Electrical and Computer Engineering and the Robotics Institute

  1. 1/30/2014 These TinyWindmills Work, and Ten Could Fit in a Grain of Rice | Wired Design | Wired.com http://www.wired.com/design/2014/01/mini-windmills-power-iphone/ 1/7

    E-Print Network [OSTI]

    Chiao, Jung-Chih

    1/30/2014 These TinyWindmills Work, and Ten Could Fit in a Grain of Rice | Wired Design | Wired.com http://www.wired.com/design/2014/01/mini-windmills-power-iphone/ 1/7 The itty-bitty blades are examples's Next Design Concept Share on Facebook 282 shares Tweet 86 184 These Tiny Windmills Work, and Ten Could

  2. 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.

  3. CaF/sub 2/:Mn thermoluminescence: a single glow peak not described by 1st or 2nd order kinetics

    SciTech Connect (OSTI)

    Hornyak, W.F.; Levy, P.W.; Kierstead, J.A.

    1984-12-01

    The thermoluminescence (TL) of CaF/sub 2/:Mn has been studied using photon counting and digital recording. For doses of 10 rad or less the TL glow curves appear to consist of a single glow peak. However, there are indications - which are pronounced at larger doses - that one additional low intensity peak (area less than or equal to one percent) is superimposed on each side of the central peak. The intense peak is not described by 1st or 2nd order kinetics but is well described by the more general kinetics from which these kinetics are derived. These observations, and the results of additional kinetic analysis, demonstrate that retrapping is not negligible and may include all three peaks. In such systems, which are likely to include other dosimeter materials and minerals, peak height will not increase linearly with dose; an important factor for dosimetry and dating applications.

  4. International Crystal Manufacturing

    E-Print Network [OSTI]

    Berns, Hans-Gerd

    International Crystal Manufacturing CRYSTAL OSCILLATOR AND FILTER PRODUCTS International Crystal Manufacturing, Inc. P.O. Box 26330 · Oklahoma City, OK 73126-0330 · Phone (405) 236-3741 Fax (405) 235@icmfg.com #12;2 International Crystal Manufacturing, Inc. P.O. Box 26330 · Oklahoma City, OK 73126-0330 · Phone

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. Cylindrical photonic crystals

    E-Print Network [OSTI]

    Ibanescu, Mihai, 1977-

    2005-01-01

    In this thesis, we explore the properties of cylindrical photonic crystal waveguides in which light is confined laterally by the band gap of a cylindrically-layered photonic crystal. We show in particular that axially-uniform ...

  10. 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.

  11. Photonic crystals Fabrication of Tunable Spherical Colloidal Crystals

    E-Print Network [OSTI]

    Photonic crystals Fabrication of Tunable Spherical Colloidal Crystals Immobilized in Soft Hydrogels** Toshimitsu Kanai, Daeyeon Lee, Ho Cheung Shum, and David A. Weitz* Spherical colloidal crystals are three as photonic crystals in the optical regime.[2] In contrast to conventional film-type colloidal crystals where

  12. 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.

  13. 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.

  14. 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.

  15. 3/3/2014 Big ideas for tinywindmills at UTA | Arlington | News from Fort Worth, Dallas, Arlingto... http://www.star-telegram.com/2014/03/02/5614443/tiny-windmills-could-save-bridges.html?rh=1 1/2

    E-Print Network [OSTI]

    Chiao, Jung-Chih

    mnagy@star-telegram.com ARLINGTON -- Millions of tiny windmills could one day power wireless sensors where they could be useful. Because companies already craft all types of charging devices for cellphones, such as powering wireless sensors located in places where making repairs might be problematic. An example would

  16. 2/21/2014 Powered byWind: World's Tiniest Windmills | Stories byWilliams http://storiesbywilliams.com/2014/02/20/the-future-is-here-tiny-windmills-to-power-cell-phones/ 1/3

    E-Print Network [OSTI]

    Chiao, Jung-Chih

    2/21/2014 Powered byWind: World's Tiniest Windmills | Stories byWilliams http://storiesbywilliams.com/2014/02/20/the-future-is-here-tiny-windmills-to-power-cell-phones/ 1/3 Stories by Williams classic sci Legacies: Preludes Search... Powered by Wind: World's Tiniest Windmills by storiesbywilliams on February 20

  17. 2/6/2014 "Grain of rice" windmills to power smartphones of tomorrow -htxt.africa http://www.htxt.co.za/2014/01/13/tiny-windmills-could-power-the-gadgets-of-tomorrow/ 1/4

    E-Print Network [OSTI]

    Chiao, Jung-Chih

    2/6/2014 "Grain of rice" windmills to power smartphones of tomorrow - htxt.africa http://www.htxt.co.za/2014/01/13/tiny-windmills-could-power-the-gadgets-of-tomorrow/ 1/4 Talk to us on Twitter Follow us" windmills to power smartphones of tomorrow When you think of wind energy the first thing that springs

  18. 3/4/2014 Big ideas for tinywindmills at UTA | Electric Power News | EnergyCentral http://www.energycentral.com/news/en/31705741/Big-ideas-for-tiny-windmills-at-UTA? 1/2

    E-Print Network [OSTI]

    Chiao, Jung-Chih

    power plant Next Nuclear, coal-fired plants will remain staples of energy industry, PPL says Email3/4/2014 Big ideas for tinywindmills at UTA | Electric Power News | EnergyCentral http Worth Star-Telegram Millions of tiny windmills could one day power wireless sensors that detect cracks

  19. Surface characterization and immersion tests of TiNi alloy coated with Ta Y. Cheng*, W. Cai, Y.F. Zheng, H.T. Li, L.C. Zhao

    E-Print Network [OSTI]

    Zheng, Yufeng

    Surface characterization and immersion tests of TiNi alloy coated with Ta Y. Cheng*, W. Cai, Y shape memory effect, superelasticity as well as excellent biocom- patibility [1­4]. With the miniature the stricture vessel by shape memory effect or supereclasticity. The improvement of the radiopacity of stents

  20. Function Photonic Crystals

    E-Print Network [OSTI]

    Xiang-Yao Wu; Bai-Jun Zhang; Jing-Hai Yang; Xiao-Jing Liu; Nuo Ba; Yi-Heng Wu; Qing-Cai Wang; Guang-Huai Wang

    2012-12-01

    In the paper, we present a new kind of function photonic crystals, which refractive index is a function of space position. Unlike conventional PCs, which structure grow from two materials, A and B, with different dielectric constants $\\epsilon_{A}$ and $\\epsilon_{B}$. By Fermat principle, we give the motion equations of light in one-dimensional, two-dimensional and three-dimensional function photonic crystals. For one-dimensional function photonic crystals, we study the dispersion relation, band gap structure and transmissivity, and compare them with conventional photonic crystals. By choosing various refractive index distribution function $n(z)$, we can obtain more width or more narrow band gap structure than conventional photonic crystals.

  1. 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.

  2. 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 0.31×0.31×0.038 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.

  3. 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.

  4. COMPILER FOR TINY REGISTER MACHINE 

    E-Print Network [OSTI]

    Wu, Sidian

    2014-09-20

    The remarkable development of embedded computing devices in the past few decades has greatly improved the computing ability of our embedded and mobile devices. Mobile phones, for example, have developed from simple telephony and messaging devices...

  5. From the tiny atom to

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformation Current HABFES OctoberEvanServicesAmesFourFrom Glimmer toSynchrotronFromFrom

  6. Commercial Application of Freeze Crystallization 

    E-Print Network [OSTI]

    Gorgol, R. G.

    1992-01-01

    crystallization for this particular application presented HPD's designers with a new set of technical challenges. The largest freeze crystallization unit in the world, prior to the Chetwynd installation, was a desalination unit in operation in Saudi Arabia...

  7. Controlling Chirality of Entropic Crystals

    E-Print Network [OSTI]

    Damasceno, Pablo F; Schultz, Benjamin A; Engel, Michael; Glotzer, Sharon C

    2015-01-01

    Colloidal crystal structures with complexity and diversity rivaling atomic and molecular crystals have been predicted and obtained for hard particles by entropy maximization. However, so far homochiral colloidal crystals, which are candidates for photonic metamaterials, are absent. Using Monte Carlo simulations we show that chiral polyhedra exhibiting weak directional entropic forces self-assemble either an achiral crystal or a chiral crystal with limited control over the crystal handedness. Building blocks with stronger faceting exhibit higher selectivity and assemble a chiral crystal with handedness uniquely determined by the particle chirality. Tuning the strength of directional entropic forces by means of particle rounding or the use of depletants allows for reconfiguration between achiral and homochiral crystals. We rationalize our findings by quantifying the chirality strength of each particle, both from particle geometry and potential of mean force and torque diagrams.

  8. Journal of Crystal Growth ] (

    E-Print Network [OSTI]

    ) at high pressure of CO2 (initial PCO2 ¼ 55 bar) and moderate to high temperature (30 and 90 1C) was used and the dissolved quantity of CO2 have a significant effect on the average particle size, specific surface areaJournal of Crystal Growth ] (

  9. 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.

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

    Office of Scientific and Technical Information (OSTI)

    CATIONS; CRYSTALLIZATION; CRYSTALLOGRAPHY; CRYSTALS; HOST; LIPIDS; MEMBRANE PROTEINS; MEMBRANES; NUCLEAR MAGNETIC RESONANCE; PEPTIDES; RANGE; SHAPE; SIZE Word Cloud More...

  11. Variable frequency photonic crystals

    E-Print Network [OSTI]

    Wu, Xiang-Yao; Liu, Xiao-Jing; Yang, Jing-Hai; Li, Hong; Chen, Wan-Jin

    2015-01-01

    In this paper, we have firstly proposed a new one-dimensional variable frequency photonic crystals (VFPCs), and calculated the transmissivity and the electronic field distribution of VFPCs with and without defect layer, and considered the effect of defect layer and variable frequency function on the transmissivity and the electronic field distribution. We have obtained some new characteristics for the VFPCs, which should be help to design a new type optical devices.

  12. 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.

  13. 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"...

  14. Growing Giant Crystals

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory ofDid you not findGeoscience/EnvironmentGlobalADDITIONALGrowing Giant Crystals

  15. 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)

  16. Continuous Plug Flow Crystallization of Pharmaceutical Compounds

    E-Print Network [OSTI]

    Alvarez, Alejandro J.

    Crystallization processes in the pharmaceutical industry are usually designed to obtain crystals with controlled size, shape, purity, and polymorphic form. Knowledge of the process conditions required to fabricate crystals ...

  17. Dissipation in a Crystallization Process

    E-Print Network [OSTI]

    Sven Dorosz; Thomas Voigtmann; Tanja Schilling

    2015-04-16

    We discuss the crystallization process from the supersaturated melt in terms of its non-equilibrium properties. In particular, we quantify the amount of heat that is produced irreversibly when a suspension of hard spheres crystallizes. This amount of heat can be interpreted as arising from the resistance of the system against undergoing phase transition. We identify an intrinsic compression rate that separates a quasi-static regime from a regime of rapid crystallization. In the former the disspated heat grows linearly in the compression rate. In the latter the system crystallizes more easily, because new relaxation channels are opened, at the cost of forming a higher fraction of non-equilibrium crystal structures. In analogy to a shear-thinning fluid, the system shows a decreased resistance when it is driven rapidly.

  18. Crystal Structures of Lipoglycopeptide Antibiotic Deacetylases...

    Office of Scientific and Technical Information (OSTI)

    Crystal Structures of Lipoglycopeptide Antibiotic Deacetylases: Implications for the Biosynthesis of A40926 and Teicoplanin Citation Details In-Document Search Title: Crystal...

  19. Frequency mixing crystal

    DOE Patents [OSTI]

    Ebbers, Christopher A. (Livermore, CA); Davis, Laura E. (Manteca, CA); Webb, Mark (Salida, CA)

    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.

  20. 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.

  1. 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.

  2. Diffraction Phenomena in Spontaneous and Stimulated Radiation by Relativistic Particles in Crystals (Review)

    E-Print Network [OSTI]

    Baryshevsky, V.G.

    2011-01-01

    crystal and originates a bent crystal channel. On the otherthe crystal and forms a bent crystal channel. In [128] the

  3. Banding in single crystals during plastic deformation

    E-Print Network [OSTI]

    Mahesh, Sivasambu

    Banding in single crystals during plastic deformation M. Arul Kumar a Sivasambu Mahesh a,b a. India. Abstract A rigid-plastic rate-independent crystal plasticity model capable of capturing band- ing such as dense dislocation walls. Key words: crystal plasticity, single crystal, macroscopic shear band, regular

  4. Active materials in photonic crystals

    E-Print Network [OSTI]

    Bermel, Peter (Peter A.)

    2007-01-01

    I analyze new phenomena arising from embedding active materials inside of photonic crystal structures. These structures strongly modify the photonic local density of states (LDOS), leading to quantitative and qualitative ...

  5. Heat transport through ion crystals

    E-Print Network [OSTI]

    Nahuel Freitas; Esteban Martinez; Juan Pablo Paz

    2014-12-09

    We study the thermodynamical properties of crystals of trapped ions which are laser cooled to two different temperatures in two separate regions. We show that these properties strongly depend on the structure of the ion crystal. Such structure can be changed by varying the trap parameters and undergoes a series of phase transitions from linear to zig-zag or helicoidal configurations. Thus, we show that these systems are ideal candidates to observe and control the transition from anomalous to normal heat transport. All structures behave as `heat superconductors', with a thermal conductivity increasing linearly with system size and a vanishing thermal gradient inside the system. However, zig-zag and helicoidal crystals turn out to be hyper sensitive to disorder having a linear temperature profile and a length independent conductivity. Interestingly, disordered 2D ion crystals are heat insulators. Sensitivity to disorder is much smaller in the 1D case.

  6. Crystal collimation for LHC

    E-Print Network [OSTI]

    Mirarchi, Daniele; Scandale, Walter; Hall, Geoffrey

    Future upgrades of the CERN Large Hadron Collider (LHC) may demand improved cleaning performance of its collimation system. Very efficient collimation is required during regular operations at high intensities, because even a small amount of energy deposited on superconducting magnets can cause an abrupt loss of superconducting conditions (quench). The present collimation system has accomplished its tasks during the LHC Run I very well, where no quench with circulating beam took place with up to 150 MJ of stored energy at 4 TeV. On the other hand, uncertainty remains on the performance at the design energy of 7 TeV and with 360 MJ of stored energy. In particular, a further increase up to about 700 MJ is expected for the high luminosity upgrade (HL-LHC), where improved cleaning performance may be needed together with a reduction of collimator impedance. The possibility to use a crystal-based collimation system represents an option for improving both cleaning performance and impedance compared to the present s...

  7. 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.

  8. 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.

  9. Crystal Potential Formula for the Calculation of Crystal Lattice Sums1 Don Steiger and Calvin Ahlbrandt

    E-Print Network [OSTI]

    Glaser, Rainer

    Crystal Potential Formula for the Calculation of Crystal Lattice Sums1 Don Steiger and Calvin; In Final Form: April 7, 1998 A new formula is derived for the determination of the potential energy of the central unit cell of a finite crystal; this formula is called the crystal potential formula. The crystal

  10. 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 world’s 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 AlphaMicron’s 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 AMI’s 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.

  11. Multiscale modeling and control of crystal shape and size distributions: accounting for crystal aggregation, evaluation of continuous crystallization systems and run-to-run control

    E-Print Network [OSTI]

    Kwon, Joseph Sangil

    2015-01-01

    continuous crystallization, an optimal condition for the production of crystals with a desired shape can be maintained until the process

  12. 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.

  13. 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.

  14. 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.

  15. Hydrodynamic interactions in colloidal crystals

    E-Print Network [OSTI]

    Weeber, Rudolf

    2011-01-01

    In dense colloids it is commonly assumed that hydrodynamic interactions do not play a role. However, a found theoretical quantification is often missing. We present computer simulations that are motivated by experiments where a large colloidal particle is dragged through a colloidal crystal. To qualify the influence of long-ranged hydrodynamics, we model the setup by conventional Langevin dynamics simulations and by an improved scheme with limited hydrodynamic interactions. This scheme significantly improves our results and allows to show that hydrodynamics strongly impacts on the development of defects, the crystal regeneration as well as on the jamming behavior.

  16. Photon tunnelling microscopy of polyethylene single crystals

    E-Print Network [OSTI]

    Srinivasarao, Mohan

    Photon tunnelling microscopy of polyethylene single crystals Mohan Srinivasarao* and Richard S:photon tunnellingmicroscopy;single crystals; polyethylene) INTRODUCTION The study of morphology of polymers is an area

  17. Defects in Self Assembled Colloidal Crystals

    E-Print Network [OSTI]

    Koh, Yaw Koon

    Colloidal self assembly is an efficient method for making 3-D ordered nanostructures suitable for materials such as photonic crystals and macroscopic solids for catalysis and sensor applications. Colloidal crystals grown ...

  18. 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.

  19. 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.

  20. 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.

  1. Compound structure one-dimensional photonic crystal

    E-Print Network [OSTI]

    Wu, Xiang-Yao; Liu, Xiao-Jing; Liang, Yu; Wang, Zhi-Guo; Fang, Yun-Tuan

    2015-01-01

    In this paper, we have proposed a new compound structure one-dimensional photonic crystal, which include series connection, parallel connection and positive and negative feedback compound structure photonic crystal. We have studied their transmission characteristics and obtained some new results, which should be help to design new type optical devices, such as optical amplifier, photonic crystal laser and so on.

  2. Nanoscale Calorimetry of Isolated Polyethylene Single Crystals

    E-Print Network [OSTI]

    Allen, Leslie H.

    Nanoscale Calorimetry of Isolated Polyethylene Single Crystals A. T. KWAN, M. YU. EFREMOV, E. A-film differential scanning calorimetry to investigate the melt- ing of isolated polyethylene single crystals of lamellar single crystals of polyethylene (PE). We obtain thickness, diffraction, and calorimetry data

  3. 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.

  4. Premelting at Defects Within Bulk Colloidal Crystals

    E-Print Network [OSTI]

    Collings, Peter

    Premelting at Defects Within Bulk Colloidal Crystals A. M. Alsayed,1 M. F. Islam,1 J. Zhang,1 P. J at grain boundaries and dislocations within bulk colloidal crystals using real- time video microscopy. The crystals are equilibrium close-packed, three- dimensional colloidal structures made from thermally

  5. Synthesis, crystal structure and luminescence properties of lanthanide...

    Office of Scientific and Technical Information (OSTI)

    English Subject: 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; 36 MATERIALS SCIENCE; COORDINATION NUMBER; CRYSTAL STRUCTURE; CRYSTALS; ENERGY TRANSFER; LIGANDS;...

  6. 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.

  7. Incoherent bremsstrahlung in flat and bent crystal

    E-Print Network [OSTI]

    N. F. Shul'ga; V. V. Syshchenko; A. I. Tarnovsky

    2010-06-03

    The bremsstrahlung cross section for relativistic electrons in a crystal is split into the sum of coherent and incoherent parts (the last is due to a thermal motion of atoms in the crystal). Although the spectrum of incoherent radiation in crystal is similar to one in amorphous medium, the incoherent radiation intensity could demonstrate substantial dependence on the crystal orientation due to the electrons' flux redistribution in the crystal. In the present paper we apply our method of the incoherent bremsstrahlung simulation developed earlier to interpretation of some recent experimental results obtained at the Mainz Microtron MAMI.

  8. Coherent bremsstrahlung in a bent crystal

    E-Print Network [OSTI]

    Bondarenco, M V

    2009-01-01

    At passage of an ultra-high-energy particle through a bent crystal coherent bremsstrahlung is emitted but with characteristic frequencies distributed continuously, in relation with the crystal bend profile. For practical crystals, such radiation can be calculated by the stationary phase approximation technique. The radiation spectrum averaged over the impact parameters is evaluated. Its characteristic feature is the presence of sharp breaks (or of the spectrum end-point) at photon energies proportional to frequencies of crystalline plane crossing at the edges of the crystal, but those features will smear out if the angular divergence of the beam is comparable to half the crystal bending angle.

  9. 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 Universität Göttingen, Tammannstraße 4, Göttingen 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.

  10. 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.

  11. 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.

  12. Meet the trillions of tiny allies that

    E-Print Network [OSTI]

    Dennett, Daniel

    & A n WALKABLE TOWNS n IS GLUTEN-FREE FOR ME? MAGA ZINE OF THE GER ALD J. AND DOROTHY R. FRIEDMAN SCHOOL the masses moving. By Julie Flaherty 17 Gluten Free-for-All Why avoiding wheat protein isn't necessarily

  13. Chemistry in Motion: Tiny Synthetic Motors

    E-Print Network [OSTI]

    Peter H. Colberg; Shang Yik Reigh; Bryan Robertson; Raymond Kapral

    2014-11-03

    In this Account, we describe how synthetic motors that operate by self-diffusiophoresis make use of a self-generated concentration gradient to drive motor motion. A description of propulsion by self-diffusiophoresis is presented for Janus particle motors comprising catalytic and noncatalytic faces. The properties of the dynamics of chemically powered motors are illustrated by presenting the results of particle-based simulations of sphere-dimer motors constructed from linked catalytic and noncatalytic spheres. The geometries of both Janus and sphere-dimer motors with asymmetric catalytic activity support the formation of concentration gradients around the motors. Because directed motion can occur only when the system is not in equilibrium, the nature of the environment and the role it plays in motor dynamics are described. Rotational Brownian motion also acts to limit directed motion, and it has especially strong effects for very small motors. We address the following question: how small can motors be and still exhibit effects due to propulsion, even if only to enhance diffusion? Synthetic motors have the potential to transform the manner in which chemical dynamical processes are carried out for a wide range of applications.

  14. A nucleon in a tiny box

    SciTech Connect (OSTI)

    Bedaque, Paulo F.; Griesshammer, Harald W.; Rupak, Gautam

    2004-07-01

    The authors use Chiral Perturbation Theory to compute the nucleon mass-shift due to finite volume and temperature effects. The results are valid up to next-to-leading order in the ''{epsilon}-regime'' (mL {approx} m{beta} << 1) as well as in the ''p-regime'' (mL {approx} m{beta} >> 1). Based on the two leading orders, they discuss the convergence of the expansion as a function of the lattice size and quark masses. This result can be used to extrapolate lattice results obtained from lattice sizes smaller than the pion cloud, avoiding the numerical simulation of physics under theoretical control. An extraction of the low-energy coefficient c{sub 3} of the chiral Lagrangean from lattice simulations at small volumes and a ''magic'' ratio {beta} = 1.22262 L might be possible.

  15. 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.

  16. Multiscale modeling and control of crystal shape and size distributions: accounting for crystal aggregation, evaluation of continuous crystallization systems and run-to-run control

    E-Print Network [OSTI]

    Kwon, Joseph Sangil

    2015-01-01

    and Size Distributions: Accounting for Crystal Aggregation,and Size Distributions: Accounting for Crystal Aggregation,steady-state growth rate accounting for the dependence of

  17. Crystal Nucleation of Colloidal Suspensions under Shear

    E-Print Network [OSTI]

    Ronald Blaak; Stefan Auer; Daan Frenkel; Hartmut Lowen

    2004-06-10

    We use Brownian Dynamics simulations in combination with the umbrella sampling technique to study the effect of shear flow on homogeneous crystal nucleation. We find that a homogeneous shear rate leads to a significant suppression of the crystal nucleation rate and to an increase of the size of the critical nucleus. A simple, phenomenological extension of classical nucleation theory accounts for these observations. The orientation of the crystal nucleus is tilted with respect to the shear direction.

  18. 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.

  19. Crystal growth and annealing for minimized residual stress

    DOE Patents [OSTI]

    Gianoulakis, Steven E. (Albuquerque, NM)

    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.

  20. 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.

  1. 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.

  2. Nanoscopic Manipulation and Imaging of Liquid Crystals

    SciTech Connect (OSTI)

    Rosenblatt, Charles S.

    2014-02-04

    This is the final project report. The project’s 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.

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

    Office of Scientific and Technical Information (OSTI)

    Structures of Phosphite Dehydrogenase Provide Insights into Nicotinamide Cofactor Regeneration Citation Details In-Document Search Title: Crystal Structures of Phosphite...

  4. Photonic crystals for high temperature applications

    E-Print Network [OSTI]

    Yeng, Yi Xiang

    2014-01-01

    This thesis focuses on the design, optimization, fabrication, and experimental realization of metallic photonic crystals (MPhCs) for high temperature applications, for instance thermophotovoltaic (TPV) energy conversion ...

  5. Scale Effects in Crystal Plasticity 

    E-Print Network [OSTI]

    Padubidri Janardhanachar, Guruprasad

    2010-07-14

    . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87 26 Schematic highlighting the steps followed in the calibration of the parameters which enter into the simulations: (a) The initial source and obstacle properties (?nuc, ??nuc, ?obs, ?obs) were calibrated to match the apparent yield and hardening.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108 37 Deformed configuration and contour plots are shown for crystal with size D = 6.4 ?m, aspect ratio (H/D) of 2:1, and initial source density of ?nuc = 20?1012 m?2 at a strain level of ? = 0.1: (a) Deformed configuration showing symmetric double...

  6. BPS States, Crystals, and Matrices

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

    Su?kowski, 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.

  7. A Complete Microfluidic Screening Platform for Rational Protein Crystallization

    E-Print Network [OSTI]

    Hansen, Carl L.

    A Complete Microfluidic Screening Platform for Rational Protein Crystallization Billy T. C. Lau integration, and low reagent consumption, microfluidic devices have emerged as viable technologies for protein crystallization. Current microfluidic crystallization technologies have focused on two separate strategies: one

  8. Using Two-Dimensional Colloidal Crystals to Understand Crystallography

    E-Print Network [OSTI]

    Loening, Niko

    Using Two-Dimensional Colloidal Crystals to Understand Crystallography Instructor Notes Geometric). #12;Using Two-Dimensional Colloidal Crystals to Understand Crystallography Instructions for Students the patterns that result from the diffraction of electromagnetic radiation by a crystal provides structural

  9. Structural Evolution of Colloidal Crystals with Increasing Ionic Strength

    E-Print Network [OSTI]

    Braun, Paul

    Structural Evolution of Colloidal Crystals with Increasing Ionic Strength Michael A. Bevan. In Final Form: June 5, 2004 We have directly observed the structural evolution of colloidal crystals colloidal crystals were shear melted and then evolved

  10. Mesoscopic Monodisperse Ferromagnetic Colloids Enable Magnetically Controlled Photonic Crystals

    E-Print Network [OSTI]

    Asher, Sanford A.

    Mesoscopic Monodisperse Ferromagnetic Colloids Enable Magnetically Controlled Photonic Crystals ferromagnetic composite particles readily self-assemble into magnetically responsive photonic crystals that efficiently Bragg diffract incident light. Magnetic fields can be used to control the photonic crystal

  11. Crystallization Kinetics of Thermosensitive Colloids Probed by Transmission Spectroscopy

    E-Print Network [OSTI]

    Wu, Jianzhong

    Crystallization Kinetics of Thermosensitive Colloids Probed by Transmission Spectroscopy Shijun hard spheres, soft spheres, and PNIPAM spheres. Introduction Crystallization of colloidal systems systems.1-15 In recent years, colloidal crystals have been used extensively for the fabrication

  12. Supramolecular chemistry and crystal engineering ASHWINI NANGIA

    E-Print Network [OSTI]

    Giri, Ranjit K.

    Supramolecular chemistry and crystal engineering ASHWINI NANGIA School of Chemistry, University. This article traces the evolution of supramolecular chemistry and crystal engineering starting from the early of Hyderabad, Hyderabad 500 046, India. e-mail: ashwini.nangia@gmail.com Advances in supramolecular chemistry

  13. 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.

  14. 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.

  15. 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.

  16. Coherent bremsstrahlung in a bent crystal

    E-Print Network [OSTI]

    M. V. Bondarenco

    2010-06-04

    Radiation spectrum from high energy $e^\\pm$ 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. Features such as sharp end of spectrum and volume reflection turnover at beginning of the spectrum are discussed. The coherence length in a bent crystal appears to depend only on the crystal geometry and not on the electron or photon energies, which is essential for interpretation of the results. Estimates of non-dipole 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 $\\sim 10^{-4}\\mathrm{rad}$.

  17. 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.

  18. Liquid crystal device and method thereof

    SciTech Connect (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.

  19. 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...

  20. 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...

  1. Microfluidic systems for continuous crystallization of small organic molecules

    E-Print Network [OSTI]

    Sultana, Mahmooda

    2010-01-01

    This thesis presents one of the first demonstrations of continuous crystallization in microfluidic devices, and illustrates their use for various applications related to crystallization of small organic molecules. ...

  2. Fractionalization of Interstitials in Curved Colloidal Crystals

    E-Print Network [OSTI]

    William T. M. Irvine; Mark J. Bowick; Paul M. Chaikin

    2013-10-11

    Understanding the out-of equilibrium behaviour of point defects in crystals, yields insights into the nature and fragility of the ordered state, as well as being of great practical importance. In some rare cases defects are spontaneously healed - a one-dimensional crystal formed by a line of identical charged particles, for example, can accommodate an interstitial (extra particle) by a re-adjusting all particle positions to even out the spacing. In sharp contrast, particles organized into a perfect hexagonal crystal in the plane cannot accommodate an interstitial by a simple re-adjustment of the particle spacing - the interstitial remains instead trapped between lattice sites and diffuses by hopping, leaving the crystal permanently defected. Here we report on the behavior of interstitials in colloidal crystals on curved surfaces. Using optical tweezers operated independently of three dimensional imaging, we insert a colloidal interstitial in a lattice of similar particles on flat and curved (positively and negatively) oil-glycerol interfaces and image the ensuing dynamics. We find that, unlike in flat space, the curved crystals self-heal through a collective rearrangement that re-distributes the increased density associated with the interstitial. The self-healing process can be interpreted in terms of an out of equilibrium interaction of topological defects with each other and with the underlying curvature. Our observations suggest the existence of "particle fractionalization" on curved surface crystals.

  3. Incoherent bremsstrahlung in flat and bent crystals

    E-Print Network [OSTI]

    N. F. Shul'ga; V. V. Syshchenko; A. I. Tarnovsky

    2011-11-01

    Incoherent bremsstrahlung by high-energy particles in crystal is due to the thermal spread of atoms in relation to their equilibrium positions in the lattice. The simulation procedure developed earlier for the incoherent radiation is applied to the case of the electrons and positrons motion in the sinusoidally bent crystal. The results of simulation are in agreement with the data of recent experiments carried out at the Mainz Microtron MAMI. The possibility of use of the sinusoidally bent crystals as undulators is discussed.

  4. 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.

  5. A procedure for diamond turning KDP crystals

    SciTech Connect (OSTI)

    Montesanti, R.C.; Thompson, S.L.

    1995-07-07

    A procedure and the equipment necessary for single-point diamond flycutting (loosely referred to as diamond turning) potassium di-hydrogen phosphate (KDP) crystals are described. It is based on current KDP diamond turning activities at the Lawrence Livermore National Laboratory (LLNL), drawing upon knowledge from the Nova crystal finishing development during the 1980`s and incorporating refinements from our efforts during 1995. In addition to describing a step-by-step process for diamond turning KDP, specific discussions are included on the necessary diamond tool geometry and edge sharpness, cutting fluid, and crystal preparation, handling, cleaning, and inspection. The authors presuppose that the reader is already familiar with diamond turning practices.

  6. Cold neutron scattering in imperfect deuterium crystals

    E-Print Network [OSTI]

    Andrzej Adamczak

    2010-12-10

    The differential cross sections for cold neutron scattering in mosaic deuterium crystals have been calculated for various target temperatures. The theoretical results are compared with the recent experimental data for the neutron wavelengths $\\lambda\\approx$~1--9~\\AA. It is shown that the structures of observed Bragg peaks can be explained by the mosaic spread of about $3^{\\circ}$ and contributions from a~limited number of crystal orientations. Such a~crystal structure should be also taken into account in ultracold neutron upscattering due to the coherent phonon annihilation in solid deuterium.

  7. Novel photonic crystal cavities and related structures.

    SciTech Connect (OSTI)

    Luk, Ting Shan

    2007-11-01

    The key accomplishment of this project is to achieve a much more in-depth understanding of the thermal emission physics of metallic photonic crystal through theoretical modeling and experimental measurements. An improved transfer matrix technique was developed to enable incorporation of complex dielectric function. Together with microscopic theory describing emitter radiative and non-radiative relaxation dynamics, a non-equilibrium thermal emission model is developed. Finally, experimental methodology was developed to measure absolute emissivity of photonic crystal at high temperatures with accuracy of +/-2%. Accurate emissivity measurements allow us to validate the procedure to treat the effect of the photonic crystal substrate.

  8. 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.

  9. NMR and NQR parameters of ethanol crystal

    E-Print Network [OSTI]

    Milinkovic, M

    2012-01-01

    Electric field gradients and chemical shielding tensors of the stable monoclinic crystal phase of ethanol are computed. The projector-augmented wave (PAW) and gauge-including projector-augmented wave (GIPAW) models in the periodic plane-wave density functional theory are used. The crystal data from X-ray measurements, as well as the structures where either all atomic, or only hydrogen atom positions are optimized in the density functional theory are analyzed. These structural models are also studied by including the semi-empirical Van der Waals correction to the density functional theory. Infrared spectra of these five crystal models are calculated.

  10. 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%).

  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, Inés; Instituto de Ciencia de Materiales de Aragón, ICMA-CSIC, Pedro Cerbuna 12, 50009 Zaragoza ; Jiménez-Ruiz, Mónica

    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. Microstructured Porous Silica Obtained via Colloidal Crystal Templates

    E-Print Network [OSTI]

    Velev, Orlin D.

    Microstructured Porous Silica Obtained via Colloidal Crystal Templates O. D. Velev,* T. A. Jede, R modified colloidal crystals as templates for silica polymerization is reported. 3D close-packed crystals, representing a negative replica of the original colloidal crystal. The size of the pores can be controlled

  13. Colloidal Crystal Templating DOI: 10.1002/anie.200705403

    E-Print Network [OSTI]

    Qi, Limin

    Angewandte Chemie Colloidal Crystal Templating DOI: 10.1002/anie.200705403 Bioinspired Fabrication or nanometer scale have not, to date, been built within a calcite single crystal. Colloidal crystals of 3D Ordered Macroporous Single Crystals of Calcite from a Transient Amorphous Phase** Cheng Li

  14. Freeze Crystallization Processes: Efficiency by Flexibility 

    E-Print Network [OSTI]

    Heist, J. A.; Barron, T. S.

    1983-01-01

    Energy consumption in fractionating solutions by distillation and evaporation can be reduced by 70% to 90% by using freeze crystallization processes. The thermodynamic bases for the substantially lower energy requirements include: 1) The phase...

  15. CRYSTALLINE REPRESENTATIONS AND F -CRYSTALS. Mark Kisin

    E-Print Network [OSTI]

    Kisin, Mark

    CRYSTALLINE REPRESENTATIONS AND F -CRYSTALS. Mark and finite flat group schemes, con* *jectured by Breuil, and to show that a crystalline representation. In this paper we generalize Breuil's theory to describe crystalline represen* *tations of higher weight or

  16. Photo-responsive liquid crystal block copolymers/

    E-Print Network [OSTI]

    Petr, Michael Thomas

    2012-01-01

    Photo-responsive liquid crystal polymers (LCP) which contain azobenzene moieties have gained interest for their ability to change properties by merely irradiating them with the correct wavelength of light in the appropriate ...

  17. 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.

  18. Soft Matter Perspective on Protein Crystal Assembly

    E-Print Network [OSTI]

    Diana Fusco; Patrick Charbonneau

    2015-07-10

    Crystallography may be the gold standard of protein structure determination, but obtaining the necessary high-quality crystals is also in some ways akin to prospecting for the precious metal. The tools and models developed in soft matter physics to understand colloidal assembly offer some insights into the problem of crystallizing proteins. This topical review describes the various analogies that have been made between proteins and colloids in that context. We highlight the explanatory power of patchy particle models, but also the challenges of providing guidance for crystallizing specific proteins. We conclude with a presentation of possible future research directions. This article is intended for soft matter scientists interested in protein crystallization as a self-assembly problem, and as an introduction to the pertinent physics literature for protein scientists more generally.

  19. 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.

  20. Crystallization and arrest mechanisms of model colloids

    E-Print Network [OSTI]

    Haxton, Thomas K; Whitelam, Stephen

    2015-01-01

    We performed dynamic simulations of spheres with short-range attractive interactions for many values of interaction strength and range. Fast crystallization occurs in a localized region of this parameter space, but the character of crystallization pathways is not uniform within this region. Pathways range from one-step, in which a crystal nucleates directly from a gas, to two-step, in which substantial liquid-like clusters form and only subsequently become crystalline. Crystallization can fail because of slow nucleation from either gas or liquid, or because of dynamic arrest caused by strong interactions. Arrested states are characterized by the formation of networks of face-sharing tetrahedra that can be detected by a local common neighbor analysis.

  1. 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.

  2. Crystal growth and detector performance of large size high-purity Ge crystals

    E-Print Network [OSTI]

    Wang, Guojian; Mei, Hao; Mei, Dongming; Irmscher, Klaus; Guan, Yutong; Yang, Gang

    2015-01-01

    High-purity germanium crystals approximately 12 cm in diameter were grown in a hydrogen atmosphere using the Czochralski method. The dislocation density of the crystals was determined to be in the range of 2000 - 4200 cm-2, which meets a requirement for use as a radiation detector. The axial and radial distributions of impurities in the crystals were measured and are discussed. A planar detector was also fabricated from one of the crystals and then evaluated for electrical and spectral performance. Measurements of gamma-ray spectra from Cs-137 and Am-241 sources demonstrate that the detector has excellent energy resolution.

  3. Crystal growth and detector performance of large size high-purity Ge crystals

    E-Print Network [OSTI]

    Guojian Wang; Mark Amman; Hao Mei; Dongming Mei; Klaus Irmscher; Yutong Guan; Gang Yang

    2015-05-07

    High-purity germanium crystals approximately 12 cm in diameter were grown in a hydrogen atmosphere using the Czochralski method. The dislocation density of the crystals was determined to be in the range of 2000 - 4200 cm-2, which meets a requirement for use as a radiation detector. The axial and radial distributions of impurities in the crystals were measured and are discussed. A planar detector was also fabricated from one of the crystals and then evaluated for electrical and spectral performance. Measurements of gamma-ray spectra from Cs-137 and Am-241 sources demonstrate that the detector has excellent energy resolution.

  4. Colloidal Particles at Chiral Liquid Crystal Interfaces

    E-Print Network [OSTI]

    Anne Claire Pawsey; Juho Lintuvuori

    2014-03-19

    Colloidal particles trapped at an interface between two fluids can form a wide range of different structures. Replacing one of the fluid with a liquid crystal increases the complexity of interactions and results in a greater range of possible structures. New behaviour emerges when colloidal particles interact with defects in the liquid crystal phases. Here we discuss the templating of colloids at a cholesteric isotropic interface.

  5. Electron Beam Production by Pyroelectric Crystals

    E-Print Network [OSTI]

    James D. Brownridge; Stephen M. Shafroth

    2002-09-20

    Pyroelectric crystals are used to produce self-focused electron beams with energies greater than 170 keV. No high voltage power supply or electron gun is needed. The system works by simply changing the temperature of a crystal of LiNbO3 or LiTaO3 by about 100oC in dilute gas. Electron beam energy spectra as well as positive-ion-beam energy spectra and profiles are shown. A change in the crystal temperature of 100oC will cause a spontaneous change in polarization. The change in polarization will be manifested by a change in charge on the surface of the crystal. It is this uncompensated charge that produces the electric field, which accelerates the electrons, or the positive ions and gives rise to the plasma, which in turn focuses them. The source of the accelerated electrons or positive ions is gas molecules ionized near the crystal surface. When the crystal surface is negative electrons are accelerated away from it and positive ions are attracted to the surface. These positive ions reduce the net negative charge on the surface thereby reducing the electric field, which causes the electron energy to decrease over time even though the focal properties remain unchanged. When the surface is positive the reverse obtains and the positive ion beam energy decreases over time as well. We will present video clips, photographic and electronic data that demonstrate many of the characteristics and applications of these electron beams.

  6. Dislocation-dynamics based crystal plasticity law for the low-and high-temperature deformation regimes of bcc crystal

    E-Print Network [OSTI]

    Devincre, Benoit

    Dislocation-dynamics based crystal plasticity law for the low- and high-temperature deformation; bcc; Crystal plasticity; Thermal activation 1. Introduction Crystal plasticity modeling at the level regimes of bcc crystal Ghiath Monnet a, , Ludovic Vincent b , Benoit Devincre c a EDF ­ R&D, MMC, avenue

  7. 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.

  8. YETI is a TinyOS plugin for Eclipse: Integration with the TinyOS toolchain

    E-Print Network [OSTI]

    ://www.sics.se/contiki/ WSN Development Phases · Simulations · Prototype experiments on the table (1-10 nodes) · Testbed environment. [1] A. Boulis. Castalia: Revealing Pitfalls in Designing Distributed Algorithms in WSN. In Sen of the MSP430 at the instruction level using MSPSim · Event-based simulation of WSN networks · Different

  9. Liquid crystals boojum-colloids

    E-Print Network [OSTI]

    M. Tasinkevych; N. M. Silvestre; M. M. Telo da Gama

    2012-04-02

    Colloidal particles dispersed in a liquid crystal lead to distortions of the director field. The distortions are responsible for long-range effective colloidal interactions whose asymptotic behaviour is well understood. The short distance behaviour of the interaction, however, is sensitive to the structure and dynamics of the topological defects nucleated near the colloidal particles in the strong anchoring regime. The full non-linear theory is required in order to determine the interaction at short separations. Spherical colloidal particles with sufficiently strong planar degenerate anchoring nucleate a pair of antipodal surface topological defects, known as boojums. We use the Landau-de Gennes formalism in order to resolve the mesoscopic structure of the boojum cores and to determine the pairwise colloidal interaction. We compare the results in three (3D) and two (2D) spatial dimensions. The corresponding free energy functionals are minimized numerically using finite elements with adaptive meshes. Boojums are always point-like in 2D, but acquire a rather complex structure in 3D which depends on the combination of the anchoring potential, the radius of the colloid, the temperature and the LC elastic anisotropy. We identify three types of defect cores in 3D which we call single, double and split core boojums, and investigate the associated structural transitions. In the presence of two colloidal particles there are substantial re-arrangements of the defects at short distances, both in 3D and 2D. These re-arrangements lead to qualitative changes in the force-distance profile when compared to the asymptotic quadrupole-quadrupole interaction. In line with the experimental results, the presence of the defects prevents coalescence of the colloidal particles in 2D, but not in 3D systems.

  10. P-10 / Z. Meng P-10 Post-Crystallization of Metal-Induced Laterally Crystallized

    E-Print Network [OSTI]

    , Tianjin 300071, P. R. China. Abstract Post-crystallization heat-treatment of metal-induced laterally/MILC poly-Si. In this paper, post-crystallization heat-treatment of MILC poly-Si thin film using YAG solid. Following the patterning of the a-Si layer into active islands, 100nm low-temperature oxide (LTO) was formed

  11. Toward photonic-crystal metamaterials: Creating magnetic emitters in photonic crystals

    E-Print Network [OSTI]

    resonances in a three-dimensional 3D photonic crystal. Photonic crystals are periodic dielectric structures be de- signed to operate even at optical frequencies, where naturally occurring materials have. Povinelli,a) Steven G. Johnson, and J. D. Joannopoulos Department of Physics and the Center for Materials

  12. CRYSTAL Simulation Code and New Coherent Effects in Bent Crystal at the LHC

    E-Print Network [OSTI]

    Sytov, Alexei I

    2014-01-01

    The LHC crystal-based collimation system is mainly addressed. A CRYSTAL simulation code for particle tracking in crystals is introduced. Its essence consists in both adequate and fast sampling of proton trajectories in crystals which is crucial for both correct description of experiments and quantitative prediction of new effects. The H8 single-pass experiment at the CERN SPS as well as 7 TeV proton deflection by a bent crystal at the LHC are simulated. We predict the existence of dechanneling peaks corresponding to the planar channeling oscillations as well as describe the possibility of their observation at high energies, specifically in the LHC crystal-assisted collimation experiment planned on 2015. An effect of excess over the amorphous level of ionization losses in the channeling mode was also found for the LHC energy. In addition, the LHC crystal-based collimation system is simulated as well as its possible improved layouts with application of a crystal with the cut and multiple volume reflection in on...

  13. Mapping mesoscale heterogeneity in the plastic deformation of a copper single crystal

    E-Print Network [OSTI]

    Magid, K. R.

    2009-01-01

    1 Introduction Crystal plasticity is a heterogeneousmodeling of crystal plasticity promise significant advancesthe mechanisms of plasticity in single crystal copper. The

  14. 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.

  15. Sieving hydrogen isotopes through two dimensional crystals

    E-Print Network [OSTI]

    M. Lozada-Hidalgo; S. Hu; O. Marshall; A. Mishchenko; A. N. Grigorenko; R. A. W. Dryfe; B. Radha; I. V. Grigorieva; A. K. Geim

    2015-11-20

    One-atom-thick crystals are impermeable to atoms and molecules, but hydrogen ions (thermal protons) penetrate through them. We show that monolayers of graphene and boron nitride can be used to separate hydrogen ion isotopes. Employing electrical measurements and mass spectrometry, we find that deuterons permeate through these crystals much slower than protons, resulting in a separation factor of 10 at room temperature. The isotope effect is attributed to a difference of about 60 meV between zero-point energies of incident protons and deuterons, which translates into the equivalent difference in the activation barriers posed by two dimensional crystals. In addition to providing insight into the proton transport mechanism, the demonstrated approach offers a competitive and scalable way for hydrogen isotope enrichment.

  16. LHC Collimation with Bent Crystals - LUA9

    E-Print Network [OSTI]

    Scandale, W; Assmann, R; Losito, R; Cavoto, G; Ivanov, Yu-M; Hall, G; Markiewicz, T; Taratin, A-M; Chesnokov, Yu-A; CERN. Geneva. The LHC experiments Committee; LHCC

    2011-01-01

    An experiment to demonstrate the feasibility of multi-stage collimation assisted by bent crystals in the Large Hadron Collider is proposed. Bent silicon crystals acting as primary collimators are expected to direct the beam halo promptly onto secondary absorbers thus ideally reducing outscattering, beam losses and the radiation load in critical regions of the ring. Extensive tests conducted by the UA9 Collaboration in the SPS and in H8 with proton and lead ion beams have shown that crystal-assisted collimation can improve the efficiency of a one-stage collimation system. The proposed experiment, called LUA9, has received full support from the CERN management, and expression of interest from three Russian Institutions (PNPI, IHEP, JINR), INFN, LAL-Orsay, Imperial College and SLAC (through the US LARP programme). This document reviews the scope, goals, organization, costs, manpower needed and the schedule of LUA9.

  17. Microscale locomotion in a nematic liquid crystal

    E-Print Network [OSTI]

    Krieger, Madison S; Powers, Thomas R

    2015-01-01

    Microorganisms often encounter anisotropy, for example in mucus and biofilms. We study how anisotropy and elasticity of the ambient fluid affects the speed of a swimming microorganism with a prescribed stroke. Motivated by recent experiments on swimming bacteria in anisotropic environments, we extend a classical model for swimming microorganisms, the Taylor swimming sheet, actuated either by transverse or longitudinal traveling waves in a three-dimensional nematic liquid crystal without twist. We calculate the swimming speed and entrained volumetric flux as a function of the swimmer's stroke properties as well as the elastic and rheological properties of the liquid crystal. The behavior is quantitatively and qualitatively well-approximated by a hexatic liquid crystal except in the cases of small Ericksen number and in a nematic fluid with tumbling parameter near the transition to a flow-aligning nematic, where anisotropic effects dominate. We also propose a novel method of swimming or pumping in a nematic flu...

  18. Sieving hydrogen isotopes through two dimensional crystals

    E-Print Network [OSTI]

    Lozada-Hidalgo, M; Marshall, O; Mishchenko, A; Grigorenko, A N; Dryfe, R A W; Radha, B; Grigorieva, I V; Geim, A K

    2015-01-01

    One-atom-thick crystals are impermeable to atoms and molecules, but hydrogen ions (thermal protons) penetrate through them. We show that monolayers of graphene and boron nitride can be used to separate hydrogen ion isotopes. Employing electrical measurements and mass spectrometry, we find that deuterons permeate through these crystals much slower than protons, resulting in a separation factor of 10 at room temperature. The isotope effect is attributed to a difference of about 60 meV between zero-point energies of incident protons and deuterons, which translates into the equivalent difference in the activation barriers posed by two dimensional crystals. In addition to providing insight into the proton transport mechanism, the demonstrated approach offers a competitive and scalable way for hydrogen isotope enrichment.

  19. Quantum Calabi-Yau and Classical Crystals

    E-Print Network [OSTI]

    Andrei Okounkov; Nikolai Reshetikhin; Cumrun Vafa

    2003-11-11

    We propose a new duality involving topological strings in the limit of large string coupling constant. The dual is described in terms of a classical statistical mechanical model of crystal melting, where the temperature is inverse of the string coupling constant. The crystal is a discretization of the toric base of the Calabi-Yau with lattice length $g_s$. As a strong evidence for this duality we recover the topological vertex in terms of the statistical mechanical probability distribution for crystal melting. We also propose a more general duality involving the dimer problem on periodic lattices and topological A-model string on arbitrary local toric threefolds. The $(p,q)$ 5-brane web, dual to Calabi-Yau, gets identified with the transition regions of rigid dimer configurations.

  20. 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.

  1. Surface acoustic waves in rotating orthorhombic crystals

    E-Print Network [OSTI]

    Michel Destrade

    2013-04-24

    The propagation of surface (Rayleigh) waves over a rotating orthorhombic crystal is studied. The crystal possesses three crystallographic axes, normal to the symmetry planes: the half-space is cut along a plane normal to one of these axes, the wave travels in the direction of another, and the rotation occurs at a uniform rate about any of the three axes. The secular equation for the surface wave speed is found explicitly; in contrast to the non-rotating case, it is dispersive (frequency-dependent). Both Coriolis and centrifugal accelerations appear in the equations of motion: none can be neglected in favor of the other, even at small rotation rates.

  2. Interface control and snow crystal growth

    E-Print Network [OSTI]

    Jessica Li; Laura P. Schaposnik

    2015-05-08

    The growth of snow crystals is dependent on the temperature and saturation of the environment. In the case of dendrites, Reiter's local two-dimensional model provides a realistic approach to the study of dendrite growth. In this paper we obtain a new geometric rule that incorporates interface control, a basic mechanism of crystallization that is not taken into account in the original Reiter's model. By defining two new variables, growth latency and growth direction, our improved model gives a realistic model not only for dendrite but also for plate forms.

  3. 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).

  4. Seismic Crystals And Earthquake Shield Application

    E-Print Network [OSTI]

    B. Baykant Alagoz; Serkan Alagoz

    2009-05-15

    We theoretically demonstrate that earthquake shield made of seismic crystal can damp down surface waves, which are the most destructive type for constructions. In the paper, seismic crystal is introduced in aspect of band gaps (Stop band) and some design concepts for earthquake and tsunami shielding were discussed in theoretical manner. We observed in our FDTD based 2D elastic wave simulations that proposed earthquake shield could provide about 0.5 reductions in magnitude of surface wave on the Richter scale. This reduction rate in magnitude can considerably reduce destructions in the case of earthquake.

  5. 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.

  6. Engineering light using large area photonic crystal devices

    E-Print Network [OSTI]

    Tandon, Sheila (Sheila N.), 1978-

    2005-01-01

    Photonic crystals are fabricated structures composed of a periodic arrangement of materials with differing indices of refraction. This research has focused on the realization of two distinct photonic crystal structures in ...

  7. First-principles intermolecular binding energies in organic molecular crystals

    E-Print Network [OSTI]

    Perger, Warren F.

    tetranitrate (PETN) using the CRYSTAL98/03 and Gaussian98 programs (with Gaussian basis sets) and the DMol crystals, for example, PETN [2] (although, of course, the lattice modes cannot be calculated this way

  8. Modeling dislocation density evolution in continuum crystal plasticity

    E-Print Network [OSTI]

    Arsenlis, Athanasios, 1975-

    2001-01-01

    Dislocations are the singly most important material defects in crystal plasticity, and although dislocation mechanics has long been understood as the underlying physical basis for continuum crystal plasticity formulations, ...

  9. Morphological control of silicalite-1 crystals using microemulsion mediated growth 

    E-Print Network [OSTI]

    Lee, Seung Ju

    2005-11-01

    space afforded by the microemulsion, is essential. The results suggest that this may be a versatile and useful approach to controlling zeolite crystal morphology and growth of crystals obtained from conventional high-silica zeolite synthesis procedures....

  10. 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)...

  11. 37A Focus on Crystallography Crystals and mathematics

    E-Print Network [OSTI]

    Greuel, Gert-Martin

    , or as polished gems. Less known is that the largest part (about 98%) of the solid ground is crystalline. This means that crystals are a stable state of the condensed matter. The term "crystal" is derived from

  12. A World's Top-10 X-ray Crystal Structure

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

    A World's Top-10 X-ray Crystal Structure October 7, 2014 Bookmark and Share Philip Coppens An x-ray crystal structure solved by Philip Coppens has been chosen as one of the world's...

  13. The experimental setup of the Interaction in Crystals for Emission...

    Office of Scientific and Technical Information (OSTI)

    high intensity sources via the coherent interactions with crystals in the sub-GeV energy range has been proved by the ICE-RAD (Interaction in Crystals for Emission of...

  14. Anomalous phenomena and spectral tailoring in photonic crystals

    E-Print Network [OSTI]

    Ghebrebrhan, Michael

    2010-01-01

    Photonic crystals are recently discovered meta-materials whose optical properties arise from periodic refractive index variations. In this thesis I examine various aspects of photonic crystals including a self-assembled ...

  15. Super-collimation in a rod-based photonic crystal

    E-Print Network [OSTI]

    Shih, Ta-Ming, Ph. D. Massachusetts Institute of Technology

    2007-01-01

    Super-collimation is the propagation of a light beam without spreading that occurs when the light beam is guided by the dispersion properties of a photonic crystal, rather than by defects in the photonic crystal. ...

  16. First-principles intermolecular binding energies in organic molecular crystals

    E-Print Network [OSTI]

    Pandey, Ravi

    , with the GAUSSIANAUSSIAN 98 program) compare reasonably well with those in experiments using crystals, for example, PETN [2

  17. Radiative sensitivities of tropical anvils to small ice crystals

    E-Print Network [OSTI]

    Zender, Charles S.; Kiehl, J. T.

    2012-01-01

    that the saturation vapor pressure drops relative to planarkm, S,- ~ 65%. The vapor pressure gradient from the crystal

  18. 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.

  19. Time Crystals from Minimum Time Uncertainty

    E-Print Network [OSTI]

    Mir Faizal; Mohammed M. Khalil; Saurya Das

    2014-12-29

    Motivated by the Generalized Uncertainty Principle, covariance, and a minimum measurable time, we propose a deformation of the Heisenberg algebra, and show that this leads to corrections to all quantum mechanical systems. We also demonstrate that such a deformation implies a discrete spectrum for time. In other words, time behaves like a crystal.

  20. The transmission of symmetry in liquid crystals

    E-Print Network [OSTI]

    Jie Xu; Pingwen Zhang

    2015-09-22

    The existing experiments and simulations suggest that the molecular symmetry is always transmitted to homogeneous phases in liquid crystals. It has been proved for rod-like molecules. We conjecture that it holds for three other symmetries, and prove it for some molecules of these symmetries.

  1. Characterization of bent crystals for Laue lenses

    E-Print Network [OSTI]

    Liccardo, V; Frontera, F; Valsan, V

    2012-01-01

    In the context of the LAUE project devoted to build a long focal-length focusing optics for soft $\\gamma$-ray astronomy (80 - 600 keV), we present the results of reflectivity measurements of bent crystals in different configurations, obtained by bending perfect or mosaic flat crystals. We also compare these results with those obtained using flat crystals. The measurements were performed using the K$\\alpha$ line of the Tungsten anode of the X-ray tube used in the LARIX facility of the University of Ferrara. These results are finalized to select the best materials and to optimize the thickness of the crystal tiles that will be used for building a Laue lens petal which is a part of an entire Laue lens, with 20 m focal length and 100-300 keV passband. The final goal of the LAUE project is overcome, by at least 2 orders of magnitude, the sensitivity limits of the current generation of $\\gamma$-ray telescopes, and to improve the current $\\gamma$-ray imaging capability.

  2. 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.

  3. 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.

  4. 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%.

  5. A study of RHIC crystal collimation

    E-Print Network [OSTI]

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

    2001-11-07

    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 an unwanted beam halo. Primary betatron collimators will be used to remove the large amplitude particles. The efficiency of the primary collimator in RHIC depends very much on the alignment of the jaws which needs to be within few micro-radians for the best 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.

  6. Module: Material Structure Focus: Crystal Packing

    E-Print Network [OSTI]

    Rowley, Clarence W.

    ) and body centered cubic. Materials: Styrofoam Balls (20) Smaller Styrofoam Ball Round Toothpicks (16-258-5598 Teacher Notes: After a short review of crystal packing, have the students take 4 Styrofoam balls the students take 8 Styrofoam balls and attach them using toothpick so that they form 2 -4 ball diamond shape

  7. Communications Counterion Effects in Liquid Crystal

    E-Print Network [OSTI]

    Braun, Paul

    such as SnS2.12 Typically, such mesoporous solids have periodic nanometer scale pores, and the mechanism of nanostructured CdS templated directly with ion-doped liquid crystals.13,14 In both cases the mesoporous solid of oligoethylene oxide (10) oleyl ether doped with cadmium acetate or cadmium chloride was utilized. In the other

  8. The diverse world of liquid crystals

    E-Print Network [OSTI]

    Palffy-Muhoray, Peter

    The diverse world of liquid crystals Peter Palffy-Muhoray Orientationally ordered soft matter are still making new discoveries and gaining deeper understanding of orientational order and its-range ori- entational, but not positional, order. A more apt name would be orientationally ordered soft

  9. 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.

  10. 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

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

    DOE Patents [OSTI]

    Payne, Stephen A. (Castro Valley, CA); Kway, Wayne L. (Fremont, CA); DeLoach, Laura D. (Manteca, CA); Krupke, William F. (Pleasanton, CA); Chai, Bruce H. T. (Oviedo, FL)

    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.

  12. Statistical Analysis of Crystallization Database Links Protein Physico-Chemical Features with Crystallization Mechanisms

    E-Print Network [OSTI]

    Fusco, Diana

    X-ray crystallography is the predominant method for obtaining atomic-scale information about biological macromolecules. Despite the success of the technique, obtaining well diffracting crystals still critically limits going ...

  13. Swimming in A Crystal: Using Colloidal Crystals to Characterise Micro-swimmers

    E-Print Network [OSTI]

    Brown, Aidan T; Dawson, Angela; Vissers, Teun; Schwarz-Linek, Jana; Lintuvuori, Juho S; Poon, Wilson C K

    2014-01-01

    We study the behaviour of hydrogen-peroxide-fuelled self-propelled Janus colloids in a 2D colloidal crystal matrix. The Janus swimmers orbit individual colloids, and hop between colloids stochastically. Analysing the hydrodynamics-induced periodic variations in their orbital speed shows that these swimmers are pushers - pushing fluid away fore and aft along their swimming axis - though we find little evidence implicating hydrodynamics in the orbital trapping itself. The hopping rate decreases with increasing fuel concentration, decreasing the swimmers' long-time diffusivity in the crystal. We find that another pusher, motile E. coli bacteria, behaves very differently in the same colloidal crystal: their well-known circular orbits on plain glass are rectified into long, straight runs in the crystal matrix, increasing their long-time diffusivity.

  14. Dislocation dynamics: from microscopic models to macroscopic crystal plasticity

    E-Print Network [OSTI]

    El Hajj, Ahmad

    Dislocation dynamics: from microscopic models to macroscopic crystal plasticity A. El Hajj , H study ranges from atomic models to macroscopic crystal plasticity. At each scale, dislocations can crystal Z3 where each position with integer coordinates is occupied by one atom. We want to describe

  15. Discrete micromechanics of elastoplastic crystals in the finite deformation range

    E-Print Network [OSTI]

    Borja, Ronaldo I.

    Available online 19 March 2014 Abstract We present a rate-independent crystal plasticity theory follows a well-established `ultimate algorithm' for rate-independent crystal plasticity developed for infinites- imal deformation. Ó 2014 Elsevier B.V. All rights reserved. Keywords: Crystal plasticity; Finite

  16. Giant Plasticity of a Quantum Crystal Ariel Haziot,1

    E-Print Network [OSTI]

    Balibar, Sébastien

    Giant Plasticity of a Quantum Crystal Ariel Haziot,1 Xavier Rojas,1 Andrew D. Fefferman,1 John R crystals may irreversibly deform. This phenomenon is known as plasticity and it is due to the motion and in the zero temperature limit, helium 4 crystals present a giant plasticity that is anisotropic and reversible

  17. Liquid crystals and Q-tensors The free energy

    E-Print Network [OSTI]

    Segatti, Antonio

    Liquid crystals and Q-tensors The free energy A temperature-dependent model Mathematical results #12;Liquid crystals and Q-tensors The free energy A temperature-dependent model Mathematical results, Non-isothermal nematic liquid crystals flows with the Ball-Majumdar free energy, Ann. Mat. Pura Appl

  18. Optical coupling between monocrystalline colloidal crystals and a planar waveguide

    E-Print Network [OSTI]

    Avrutsky, Ivan

    Optical coupling between monocrystalline colloidal crystals and a planar waveguide Y. Zhao,a) I demonstrated an optical material structure consisting of monocrystalline colloidal crystals and a planar struc- ture consisting of a planar waveguide and polycrystalline colloidal crystals.8 In this letter, we

  19. Characterization of internal order of colloidal crystals by optical diffraction

    E-Print Network [OSTI]

    Sargent, Edward H. "Ted"

    Characterization of internal order of colloidal crystals by optical diffraction M A T H I E U A L L of the internal order of colloidal crystals and to identify optimum growth conditions. This work leads shear, photonic crystal 1. Introduction A great deal of attention has recently been devoted to colloidal

  20. Introduction Liquid crystals [1] and colloids [2] are interesting model

    E-Print Network [OSTI]

    Schofield, Andrew B.

    Introduction Liquid crystals [1] and colloids [2] are interesting model systems for fundamental, 8] and by computer simulations [9]. When combining liquid crystals with colloids, typically-molecular weight liquid crystals with colloids or droplets [10, 12­ 18]. Inverted nematic emulsions may form

  1. Noncentral Forces in Crystals of Charged Colloids D. Reinke,1

    E-Print Network [OSTI]

    Schofield, Andrew B.

    Noncentral Forces in Crystals of Charged Colloids D. Reinke,1 H. Stark,2 H.-H. von Gru¨nberg,3 properties of fcc crystals consisting of charge stabilized colloidal particles are determined from real space, the question arises whether the elastic proper- ties of colloidal crystals are comparable to metals and whether

  2. Ionic colloidal crystals of oppositely charged Mirjam E. Leunissen1

    E-Print Network [OSTI]

    Leunissen, Mirjam

    Ionic colloidal crystals of oppositely charged particles Mirjam E. Leunissen1 *, Christina G charged particles can be tuned such that large ionic colloidal crystals form readily, with our theory, the stoichio- metry of our colloidal crystals is not dictated by charge neutrality; this allows us to obtain

  3. D-D Nuclear Fusion Using Different Size Pyroelectric Crystals

    E-Print Network [OSTI]

    Danon, Yaron

    D-D Nuclear Fusion Using Different Size Pyroelectric Crystals A. M. Kovanen, D. J. Gillich, T. Z the conditions for D-D fusion in pyroelectric crystal accelerators. Three different pyroelectric crystal sizes are with the Department of Mechanical, Aerospace and Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, NY. A. M

  4. 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 UV–vis–NIR 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 UV–vis–NIR 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.

  5. Simulation of beam steering phenomena in bent crystals

    E-Print Network [OSTI]

    Valery M. Biryukov

    2001-11-06

    The simulation methods for the channeling phenomena in GeV/TeV energy range in ideal or distorted crystal lattices are discussed. Monte Carlo predictions for feed-out and feed-in rates, dislocation dechanneling, and deflection efficiencies of bent crystals are compared to the experimental data. The role of multiple interactions with crystal in circular accelerators ("multipass channeling") for the efficiency boost in the crystal-aided extraction experiments is analysed. Possible future applications of the crystal channeling technique are considered.

  6. Inorganic arrangement crystal beryllium, lithium, selenium and silicon

    E-Print Network [OSTI]

    Gobato, Ricardo; Fedrigo, Desire Francine Gobato

    2015-01-01

    The use of inorganic crystals technology has been widely date. Since quartz crystals for watches in the nineteenth century, and common way radio in the early twentieth century, to computer chips with new semiconductor materials. Chemical elements such as beryllium, lithium, selenium and silicon, are widely used in technology. The development of new crystals arising from that arrangement can bring technological advances in several areas of knowledge. The likely difficulty of finding such crystals in nature or synthesized, suggest an advanced study of the subject. A study using computer programs with ab initio method was applied. As a result of the likely molecular structure of the arrangement of a crystal was obtained.

  7. Strongly Driven Crystallization Processes in a Metallic Glass

    SciTech Connect (OSTI)

    LaGrange, T; Grummon, D S; Reed, B W; Browning, N D; King, W E; Campbell, G H

    2009-02-09

    The crystallization of amorphous NiTi thin films was studied in situ using pulsed laser heating in a dynamic transmission electron microscope. A single pulse can crystallize small areas of the film within 2 {micro}s. The crystallized volume fraction and morphology depend strongly on the laser energy, the laser spatial profile, and the heat transport in the film. As compared to slower furnace and continuous wave laser annealing, pulsed laser heating produces a dramatically different microstructure. Higher than expected crystallization rates were observed under pulsed irradiation that do not correlate with kinetic data obtained from the slow-heating crystallization experiments.

  8. Large effect of polydispersity on defect concentrations in colloidal crystals

    E-Print Network [OSTI]

    Sander Pronk; Daan Frenkel

    2004-02-03

    We compute the equilibrium concentration of stacking faults and point defects in polydisperse hard-sphere crystals. We find that, while the concentration of stacking faults remains similar to that of monodisperse hard sphere crystals, the concentration of vacancies decreases by about a factor two. Most strikingly, the concentration of interstitials in the maximally polydisperse crystal may be some six orders of magnitude larger than in a monodisperse crystal. We show that this dramatic increase in interstitial concentration is due to the increased probability of finding small particles and that the small-particle tail of the particle size distribution is crucial for the interstitial concentration in a colloidal crystal.

  9. 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.

  10. Advanced Bent Crystal Collimation Studies at the Tevatron (T-980)

    E-Print Network [OSTI]

    Zvoda, V; Carrigan, R; Drozhdin, A; Johnson, T; Kwan, S; Mokhov, N; Prosser, A; Reilly, R; Uplegger, R Rivera L; Shiltsev, V; Still, D; Zagel, J; Guidi, V; Bagli, E; Mazzolari, A; Ivanov, Yu; Chesnokov, Yu; Yazynin, I

    2011-01-01

    The T-980 bent crystal collimation experiment at the Tevatron has recently acquired substantial enhancements. First, two new crystals - a 16-strip one manufactured and characterized by the INFN Ferrara group and a quasi-mosaic crystal manufactured and characterized by the PNPI group. Second, a two plane telescope with 3 high-resolution pixel detectors per plane along with corresponding mechanics, electronics, control and software has been manufactured, tested and installed in the E0 crystal region. The purpose of the pixel telescope is to measure and image channeled (CH), volume-reflected (VR) and multiple volume-reflected (MVR) beam profiles produced by bent crystals. Third, an ORIGIN-based system has been developed for thorough analysis of experimental and simulation data. Results of analysis are presented for different types of crystals used from 2005 to present for channeling and volume reflection including pioneering tests of two-plane crystal collimation at the collider, all in comparison with detailed ...

  11. 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.

  12. Multiscale modeling and control of crystal shape and size distributions: accounting for crystal aggregation, evaluation of continuous crystallization systems and run-to-run control

    E-Print Network [OSTI]

    Kwon, Joseph Sangil

    2015-01-01

    of continuous crystallization process . . . . . . . 99demonstrated that a continuous process with a fines trap canresidence time of a continuous process is typically one or

  13. Partial rotational lattice order–disorder in stefin B crystals

    SciTech Connect (OSTI)

    Renko, Miha [Josef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia); Centre of Excellence for Integrated Approaches in Chemistry and Biology of Proteins, Jamova 39, SI-1000 Ljubljana (Slovenia); Taler-Ver?i?, Ajda [Josef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia); Miheli?, Marko [Josef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia); Centre of Excellence for Integrated Approaches in Chemistry and Biology of Proteins, Jamova 39, SI-1000 Ljubljana (Slovenia); Žerovnik, Eva [Josef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia); Turk, Dušan, E-mail: dusan.turk@ijs.si [Josef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia); Centre of Excellence for Integrated Approaches in Chemistry and Biology of Proteins, Jamova 39, SI-1000 Ljubljana (Slovenia)

    2014-04-01

    Crystal lattice disorders are a phenomenon which may hamper the determination of macromolecular crystal structures. Using the case of the crystal structure of stefin B, identification of rotational order–disorder and structure determination are described. At present, the determination of crystal structures from data that have been acquired from twinned crystals is routine; however, with the increasing number of crystal structures additional crystal lattice disorders are being discovered. Here, a previously undescribed partial rotational order–disorder that has been observed in crystals of stefin B is described. The diffraction images revealed normal diffraction patterns that result from a regular crystal lattice. The data could be processed in space groups I4 and I422, yet one crystal exhibited a notable rejection rate in the higher symmetry space group. An explanation for this behaviour was found once the crystal structures had been solved and refined and the electron-density maps had been inspected. The lattice of stefin B crystals is composed of five tetramer layers: four well ordered layers which are followed by an additional layer of alternatively placed tetramers. The presence of alternative positions was revealed by the inspection of electron-density score maps. The well ordered layers correspond to the crystal symmetry of space group I422. In addition, the positions of the molecules in the additional layer are related by twofold rotational axes which correspond to space group I422; however, these molecules lie on the twofold axis and can only be related in a statistical manner. When the occupancies of alternate positions and overlapping are equal, the crystal lattice indeed fulfills the criteria of space group I422; when these occupancies are not equal, the lattice only fulfills the criteria of space group I4.

  14. Symmetric Satellite Swarms and Choreographic Crystals

    E-Print Network [OSTI]

    Latham Boyle; Jun Yong Khoo; Kendrick Smith

    2014-07-22

    In this paper, we introduce a natural dynamical analogue of crystalline order, which we call choreographic order. In an ordinary (static) crystal, a high degree of symmetry may be achieved through a careful arrangement of the fundamental repeated elements. In the dynamical analogue, a high degree of symmetry may be achieved by having the fundamental elements perform a carefully choreographed dance. For starters, we show how to construct and classify all symmetric satellite constellations. Then we explain how to generalize these ideas to construct and classify choreographic crystals more broadly. We introduce a quantity, called the "choreography" of a given configuration. We discuss the possibility that some (naturally occurring or artificial) many-body or condensed-matter systems may exhibit choreographic order, and suggest natural experimental signatures that could be used to identify and characterize such systems.

  15. Transmission Character of General Function Photonic Crystals

    E-Print Network [OSTI]

    Xiang-Yao Wu; Bo-Jun Zhang; Jing-Hai Yang; Si-Qi Zhang; Xiao-Jing Liu; Jing Wang; Nuo Ba; Zhong Hua; Xin-Guo Yin

    2012-12-01

    In the paper, we present a new general function photonic crystals (GFPCs), which refractive index of medium is a arbitrary function of space position. Unlike conventional photonic crystals (PCs), which structure grow from two mediums $A$ and $B$, with different constant refractive indexes $n_{a}$ and $n_{b}$. Based on Fermat principle, we give the motion equations of light in one-dimensional GFPCs, and calculate its transfer matrix, which is different from the conventional PCs. We choose the linearity refractive index function for two mediums $A$ and $B$, and find the transmissivity of one-dimensional GFPCs can be much larger or smaller than 1 for different slope linearity refractive index function, which is different from the transmissivity of conventional PCs (its transmissivity is in the range of 0 and 1). Otherwise, we study the effect of different incident angles, the number of periods and optical thickness on the transmissivity, and obtain some new results different from the conventional PCs.

  16. UCN transport simulation in solid deuterium crystals

    E-Print Network [OSTI]

    Yu. N. Pokotilovski

    2012-03-04

    The extraction efficiency of ultracold neutrons from cryogenic moderators depends critically on the neutron transparency of the moderator material. The Monte Carlo simulation of the probability of the UCN going out from non-ideal (disordered) solid deuterium crystals has been performed. It was based on the use of the correlation function describing the density fluctuations in a disordered material, the latter being inferred from the measured very low neutron energy total cross sections for this material.

  17. 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.

  18. Method for fabricating apatite crystals and ceramics

    SciTech Connect (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.

  19. Microscale locomotion in a nematic liquid crystal

    E-Print Network [OSTI]

    Madison S. Krieger; Saverio E. Spagnolie; Thomas R. Powers

    2015-09-18

    Microorganisms often encounter anisotropy, for example in mucus and biofilms. We study how anisotropy and elasticity of the ambient fluid affects the speed of a swimming microorganism with a prescribed stroke. Motivated by recent experiments on swimming bacteria in anisotropic environments, we extend a classical model for swimming microorganisms, the Taylor swimming sheet, actuated either by transverse or longitudinal traveling waves in a three-dimensional nematic liquid crystal without twist. We calculate the swimming speed and entrained volumetric flux as a function of the swimmer's stroke properties as well as the elastic and rheological properties of the liquid crystal. The behavior is quantitatively and qualitatively well-approximated by a hexatic liquid crystal except in the cases of small Ericksen number and in a nematic fluid with tumbling parameter near the transition to a flow-aligning nematic, where anisotropic effects dominate. We also propose a novel method of swimming or pumping in a nematic fluid by passing a traveling wave of director oscillation along a rigid wall.

  20. Microscale locomotion in a nematic liquid crystal

    E-Print Network [OSTI]

    Madison S. Krieger; Saverio E. Spagnolie; Thomas R. Powers

    2015-07-02

    Microorganisms often encounter anisotropy, for example in mucus and biofilms. We study how anisotropy and elasticity of the ambient fluid affects the speed of a swimming microorganism with a prescribed stroke. Motivated by recent experiments on swimming bacteria in anisotropic environments, we extend a classical model for swimming microorganisms, the Taylor swimming sheet, actuated either by transverse or longitudinal traveling waves in a three-dimensional nematic liquid crystal without twist. We calculate the swimming speed and entrained volumetric flux as a function of the swimmer's stroke properties as well as the elastic and rheological properties of the liquid crystal. The behavior is quantitatively and qualitatively well-approximated by a hexatic liquid crystal except in the cases of small Ericksen number and in a nematic fluid with tumbling parameter near the transition to a flow-aligning nematic, where anisotropic effects dominate. We also propose a novel method of swimming or pumping in a nematic fluid by passing a traveling wave of director oscillation along a rigid wall.

  1. 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.

  2. 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.

  3. Robustness Test of a Silicon Strip Crystal for Crystal-Assisted Collimation Studies in the LHC

    E-Print Network [OSTI]

    Lechner, A; Di Castro, M; Lendaro, J; Loprete, F; Losito, R; Maglioni, C; Masi, A; Montesano, S; Perillo-Marcone, A; Roguet, P S; Wollmann, D; Sancho, J B; Burkart, F; Scandale, W; Gavrikov, Y; Guidi, V; Mazzolari, A

    2013-01-01

    Over the past years, the UA9 experiment has successfully demonstrated the viability of enhancing the collimation efficiency of proton and ion beams in the SPS by means of bent crystals. An extension of UA9 to the LHC has been recently approved. The conditions imposed by the LHC operational environment, in particular the tremendous energy density of the beam, require a reliable understanding of the crystal integrity in view of potential accident scenarios such as an asynchronous beam dump. For this purpose, single pulse irradiation tests have been performed at the CERN-HiRadMat facility to examine the mechanical strength of a silicon strip crystal in case of direct beam impact. The tests were carried out using a 440 GeV proton beam of ?=0.5 mm transverse size. Individual pulse intensities reached up to 3×1013 protons, where a significant fraction is assumed to have impacted on the crystal. First visual inspections revealed no macroscopic damage to the crystal. Complementary post-irradiation tests are foresee...

  4. Invited Review Article: Development of crystal lenses for energetic photons

    SciTech Connect (OSTI)

    Smither, Robert K. [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

    2014-08-15

    This paper follows the development of crystal diffraction lenses designed to focus energetic photons. It begins with the search for a solution to the astrophysics problem of how to detect weak astrophysics sources of gamma rays and x-rays. This led to the basic designs for a lens and to the understanding of basic limitations of lens design. The discussion of the development of crystal diffraction lenses is divided into two parts: lenses using crystals with mosaic structure, and lenses that use crystals with curved crystal planes. This second group divides into two sub-groups: (1) Curved crystals that are used to increase the acceptance angle of the diffraction of a monochromatic beam and to increase the energy bandwidth of the diffraction. (2) Curved crystals used to focus gamma ray beams. The paper describes how these two types of crystals affect the design of the corresponding crystal lenses in different fields: astrophysics, medical imaging, detection of weak, distant, gamma-ray sources, etc. The designs of crystal lenses for these applications are given in enough detail to allow the reader to design a lens for his own application.

  5. 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.

  6. 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).

  7. Ytterbium-doped borate fluoride laser crystals and lasers

    DOE Patents [OSTI]

    Schaffers, Kathleen I. (Pleasanton, CA); DeLoach, Laura D. (Manteca, CA); Payne, Stephen A. (Castro Valley, CA); Keszler, Douglas A. (Corvallis, OK)

    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.

  8. 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.

  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. 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.

  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, 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.

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

    DOE Patents [OSTI]

    James, Ralph (5420 Lenore Ave., Livermore, CA 94550); Burger, Arnold (753 Adkisson La., Nashville, TN 37205); Chen, Kuo-Tong (7800 River Fork Dr., Nashville, TN 37221); Chang, Henry (6535 Premier Dr., Apt. A7, Nashville, TN 37209)

    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.

  14. 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.

  15. 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.

  16. Observation of scattering and absorption centers in lead fluoride crystals

    E-Print Network [OSTI]

    Patrick Achenbach

    2006-06-22

    For the first time, lead fluoride is used as a fast and compact material in electromagnetic calorimetry. Excellent optical and mechanical properties of the pure Cherenkov crystals are necessary for the A4 collaboration to perform a measurement of the nucleon's strange form factors. Visible scattering and absorption centers as well as surface damages have been investigated to characterize the quality of more than one thousand crystals. Besides, transmittance measurements have been performed on all crystals to reveal absorption bands produced by intrinsic or impurity related point-structure defects. As a consequence, 89 crystals had to be replaced by the Chinese manufacturer SICCAS.

  17. Multiscale Modeling, Simulation and Control of Protein Crystallization Processes

    E-Print Network [OSTI]

    Nayhouse, Michael Jeffrey

    2015-01-01

    Stochastic simulation of chemical kinetics. Annu. Rev. Phys.in protein crystal growth. Chemical Engineering Science, 87:time evolution of coupled chemical reactions. J. Comput.

  18. 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.

  19. 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.

  20. 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.

  1. 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...

  2. Strong solutions of the compressible nematic liquid crystal flow

    E-Print Network [OSTI]

    2011-04-29

    Apr 29, 2011 ... nematic liquid crystal flows in a domain ? ? R3. We first prove the local ... natural compatibility condition. The initial density .... gas dynamics).

  3. 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...

  4. Crystal Structures of the Synaptotagmin-SNARE Complex that is...

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

    Crystal Structures of the Synaptotagmin-SNARE Complex that is Essential for Synchronous Synaptic Neurotransmitter Release Saturday, October 31, 2015 Scientists at Stanford...

  5. 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.

  6. 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.

  7. Method for the preparation of photochromic insulating crystals

    DOE Patents [OSTI]

    Abraham, Marvin M. (Oak Ridge, TN); Boldu, Jose L. (Mexico City, MX); Chen, Yok (Oak Ridge, TN); Orera, Victor M. (Zaragosa, ES)

    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.

  8. A Variational Model for Bent-Core Liquid Crystals

    E-Print Network [OSTI]

    2007-05-17

    THE 3RD SYMPOSIUM ON ANALYSIS AND PDES. PURDUE UNIVERSITY, MAY 27–30, 2007. A VARIATIONAL MODEL FOR BENT-CORE LIQUID CRYSTALS.

  9. Total internal reflection photonic crystal prism Ethan Schonbrun1

    E-Print Network [OSTI]

    Fainman, Yeshaiahu

    Total internal reflection photonic crystal prism Ethan Schonbrun1 , Maxim Abashin2 , John Blair3 of Electrical and Computer Engineering, University of Colorado, Boulder, Colorado, 80309 ethan

  10. 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.

  11. 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.

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

    DOE Patents [OSTI]

    Wright, Gomez W. (Nashville, TN); James, Ralph B. (Livermore, CA); Burger, Arnold (Nashville, TN); Chinn, Douglas A. (Livermore, CA)

    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.

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

    DOE Patents [OSTI]

    Wright, Gomez W. (Nashville, TN); James, Ralph B. (Livermore, CA); Burger, Arnold (Nashville, TN); Chinn, Douglas A. (Livermore, CA)

    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.

  14. Damage due to salt crystallization in porous media

    E-Print Network [OSTI]

    Noushine Shahidzadeh Bonn; Francois Bertrand; Daniel Bonn

    2009-06-13

    We investigate salt crystallization in porous media that can lead to their disintegration. For sodium sulfate we show for the first time experimentally that when anhydrous crystals are wetted with water, there is very rapid growth of the hydrated form of sulfate in clusters that nucleate on anhydrous salt micro crystals. The molar volume of the hydrated crystals being four times bigger, the growth of these clusters can generate stresses in excess of the tensile strength of the stone and lead therefore to damage.

  15. 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.

  16. 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.

  17. A Submarine Welded Ignimbrite-Crystal-Rich Sandstone Facies Associatio...

    Open Energy Info (EERE)

    ignimbrite). Breccia units composed of welded ignimbrite clasts and crystal-rich matrix (e.g., Comstock and Anthony Road ignimbrite breccias) imply that some welded...

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

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

    of authenticity, and indeed, the Los Alamos instruments confirmed that it was not a world-record trapezohedral crystal. Further interpretation of the results will also provide...

  19. 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...

  20. Physical Modeling of Spinel Crystals Settling at Low Reynolds...

    Office of Scientific and Technical Information (OSTI)

    waste (HLW) vitrification process poses a potential danger to electrically heated ceramic melters. Large spinel crystals rapidly settle under gravitational attraction and...

  1. PHOTOCATALYTIC AND PHOTOELECTROCHEMICAL HYDROGEN PRODUCTION ON STRONTIUM TITANATE SINGLE CRYSTALS

    E-Print Network [OSTI]

    Wagner, F.T.

    2012-01-01

    AND PHOTOELECTROCHEMICAL HYDROGEN PRODUCTION ON STRONTIUMAND PHOTOELECTROCHEHICAL HYDROGEN PRODUCTION ON STRONTIUMand photocatalytic hydrogen production from SrTi0 3 crystals

  2. Application of spatially resolved high resolution crystal spectrometry...

    Office of Scientific and Technical Information (OSTI)

    Country of Publication: United States Language: English Subject: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; CRYSTALS;...

  3. Elastic interface acoustic waves in twinned crystals

    E-Print Network [OSTI]

    Michel Destrade

    2013-04-30

    A new type of Interface Acoustic Waves (IAW) is presented, for single-crystal orthotropic twins bonded symmetrically along a plane containing only one common crystallographic axis. The effective boundary conditions show that the waves are linearly polarized at the interface, either transversally or longitudinally. Then the secular equation is obtained in full analytical form using new relationships for the displacement-traction quadrivector at the interface. For Gallium Arsenide and for Silicon, it is found that the IAWs with transverse (resp. longitudinal) polarization at the interface are of the Stoneley (resp. leaky) type.

  4. Coarsening Dynamics of Biaxial Nematic Liquid Crystals

    E-Print Network [OSTI]

    N. V. Priezjev; Robert A. Pelcovits

    2002-02-14

    We study the coarsening dynamics of two and three dimensional biaxial nematic liquid crystals, using Langevin dynamics. Unlike previous work, we use a model with no a priori relationship among the three elastic constants associated with director deformations. We find a rich variety of coarsening behavior, including the simulataneous decay of nearly equal populations of the three classes of half-integer disclination lines. The behavior we observed can be understood on the basis of the relative values of the elastic constants and the resulting decay channels of the defects.

  5. 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.

  6. Weak crystallization theory of metallic alloys

    E-Print Network [OSTI]

    Ivar Martin; Sarang Gopalakrishnan; Eugene A. Demler

    2015-06-09

    We extend the Weak Crystallization theory to the case of metallic alloys. The additional ingredient -- itinerant electrons -- generates nontrivial dependence of free energy on the angles between ordering wave vectors of ionic density. That leads to stabilization of FCC, Rhombohedral, and icosahedral quasicrystalline (iQC) phases, which are absent in the generic theory with only local interactions. The condition for stability of iQC that we find, is consistent with the Hume-Rothery rules known empirically for majority of stable iQC; namely, the length of the primary Bragg peak wavevector is approximately equal to the diameter of the Fermi surface.

  7. 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.

  8. 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.

  9. Polarization and adiabatic pumping in inhomogeneous crystals

    SciTech Connect (OSTI)

    Xiao, Di [ORNL; Shi, Junren [Institute of Physics, Chinese Academy of Science; Clougherty, Dennis [University of Vermont; Niu, Qian [University of Texas, Austin

    2009-01-01

    We develop a general theory of electric polarization in crystals with inhomogeneous order. We show that the inhomogeneity-induced polarization can be classified into two parts: a perturbative contribution stemming from a correction to the basis functions and a topological contribution described in terms of the Chern-Simons form of the Berry gauge fields. The latter is determined up to an uncertainty quantum, which is the second Chern number in appropriate units. Our theory provides an exhaustive link between microscopic models and the macroscopic polarization.

  10. Dynamical States in Driven Colloidal Liquid Crystals

    E-Print Network [OSTI]

    Ellen Fischermeier; Matthieu Marechal; Klaus Mecke

    2014-09-24

    We study a model colloidal liquid crystal consisting of hard spherocylinders under the influence of an external aligning potential by Langevin dynamics simulation. The external field that rotates in a plane acts on the orientation of the individual particles and induces a variety of collective nonequilibrium states. We characterize these states by the time-resolved orientational distribution of the particles and explain their origin using the single particle behavior. By varying the external driving frequency and the packing fraction of the spherocylinders we construct the dynamical state diagram.

  11. Crystal Structure of Iron-dependent Halogenase

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room News PublicationsAuditsClusterInformationContractCorporateCrooker namedDistrictsCrystal

  12. Evaporation-Driven Fast Crystallization of 3D Micro- and Nano-particle Assemblies via Micro Mechanical Systems

    E-Print Network [OSTI]

    Choi, Sun

    2012-01-01

    of two-dimensional colloidal crystals, Chemical Physicssubstrates templated by colloidal crystal films, Journal ofof a Monolayer Colloidal Crystal by Meniscus Pinning,

  13. 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.

  14. Flexible LEDs bring light to fingertips Oct 19, 2010

    E-Print Network [OSTI]

    Rogers, John A.

    Flexible LEDs bring light to fingertips Oct 19, 2010 Glowing gloves Light-emitting diodes ­ or LEDs counterparts, known as holes, are driven into the well where they combine to emit light. LEDs are normally made that is populated with red LEDs. Stitches incorporating these tiny light emitters have been inserted

  15. Vortex Molecular Crystal and Vortex Plastic Crystal States in Honeycomb and Kagome Pinning Arrays

    E-Print Network [OSTI]

    C. Reichhardt; C. J. Olson Reichhardt

    2007-07-26

    Using numerical simulations, we investigate vortex configurations and pinning in superconductors with honeycomb and kagome pinning arrays. We find that a variety of novel vortex crystal states can be stabilized at integer and fractional matching field densities. The honeycomb and kagome pinning arrays produce considerably more pronounced commensuration peaks in the critical depinning force than triangular pinning arrays, and also cause additional peaks at noninteger matching fields where a portion of the vortices are located in the large interstitial regions of the pinning lattices. For the honeycomb pinning array, we find matching effects of equal strength at most fillings B/B_\\phi=n/2 for n>2, where n is an integer, in agreement with recent experiments. For kagome pinning arrays, pronounced matching effects generally occur at B/B_\\phi=n/3 for n>3, while for triangular pinning arrays pronounced matching effects are observed only at integer fillings B/B_\\phi=n. At the noninteger matching field peaks in the honeycomb and kagome pinning arrays, the interstitial vortices are arranged in dimer, trimer, and higher order n-mer states that have an overall orientational order. We call these n-mer states "vortex molecular crystals" and "vortex plastic crystals" since they are similar to the states recently observed in colloidal molecular crystal systems. We argue that the vortex molecular crystals have properties in common with certain spin systems such as Ising and n-state Potts models. We show that kagome and honeycomb pinning arrays can be useful for increasing the critical current above that of purely triangular pinning arrays.

  16. 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.

  17. Levitated crystals and quasicrystals of metamaterials

    SciTech Connect (OSTI)

    Wang, Zhehui [Los Alamos National Laboratory; Morris, Christopher [Los Alamos National Laboratory; Goree, John A [Dept Phys and Astron., University of Iowa

    2012-07-25

    New scientific and technological opportunities exist by marrying dusty plasma research with metamaterials. Specifically, by balancing control and self-assembly, certain laboratory plasmas can become a generic levitation platform for novel structure formation and nanomaterial synthesis. We propose to experimentally investigate two dimensional (2D) and three dimensional (3D) levitated structures of metamaterials and their properties. Such structures can self assemble in laboratory plasmas, similar to levitated dust crystals which were discovered in the mid 1990's. Laboratory plasma platform for metamaterial formation eliminates substrates upon which most metamaterials have to be supported. Three types of experiments, with similar setups, are discussed here. Levitated crystal structures of metamaterials using anisotropic microparticles are the most basic of the three. The second experiment examines whether quasicrystals of metamaterials are possible. Quasicrystals, discovered in the 1980's, possess so-called forbidden symmetries according to the conventional crystallography. The proposed experiment could answer many fundamental questions about structural, thermal and dynamical properties of quasicrystals. And finally, how to use nanoparticle coated microparticles to synthesize very long carbon nanotubes is also described. All of the experiments can fit inside a standard International Space Station locker with dimensions of 8-inch x 17-inch X 18-inch. Microgravity environment is deemed essential in particular for large 3D structures and very long carbon nanotube synthesis.

  18. Formation of Spatially Patterned Colloidal Photonic Crystals through the Control of Capillary Forces and

    E-Print Network [OSTI]

    Parikh, Atul N.

    Formation of Spatially Patterned Colloidal Photonic Crystals through the Control of Capillary colloidal crystals using physical confinement in conjunction with surfaces displaying predetermined binary planar colloidal crystals. These methods rely on controlled gravitational settling or solvent evaporation

  19. Fourier's Law for a Harmonic Crystal with Selfconsistent Stochastic Reservoirs

    E-Print Network [OSTI]

    Roma "La Sapienza", Università di

    Fourier's Law for a Harmonic Crystal with Self­consistent Stochastic Reservoirs Federico Bonetto. The corresponding heat cur­ rent satisfies Fourier's law with a finite positive thermal conductivity which can also words: Fourier's law; harmonic crystal; non­equilibrium systems; ther­ modynamic limit; Green

  20. STRUCTURAL VIROLOGY X-ray crystal structures of native

    E-Print Network [OSTI]

    Napp, Nils

    STRUCTURAL VIROLOGY X-ray crystal structures of native HIV-1 capsid protein reveal conformational) hexamers that shield the viral genome and proteins have been elusive. We report crystal structures-binding site. Inherent structural plasticity, hydration layer rearrangement, and effector binding affect capsid

  1. MATERIALS PERSPECTIVE Intermittent plastic flow of single crystals

    E-Print Network [OSTI]

    Niewczas, Marek

    MATERIALS PERSPECTIVE Intermittent plastic flow of single crystals: central problems in plasticity: a review M. Niewczas* The relationships between microstructure and plastic flow properties of copper single crystals deformed at low temperatures are reviewed based on the analysis of experimental results

  2. Technology Reports Solution Concentration Prediction for Pharmaceutical Crystallization Processes

    E-Print Network [OSTI]

    Using Robust Chemometrics and ATR FTIR Spectroscopy Timokleia Togkalidou, Hsien-Hsin Tung,*, Yongkui Sun systems in the presence of impurities and over a wide range of temperature. To our best knowledge in pharmaceutical industry such as crystal size distribution (CSD) and crystal shape of the product pharmaceuticals

  3. Photonic Crystal Slot Waveguide Spectrometer for Detection of Methane

    E-Print Network [OSTI]

    Texas at Austin, University of

    Photonic Crystal Slot Waveguide Spectrometer for Detection of Methane 1 Funded by Environmental. of Electrical and Computer Engineering, University of Texas, Austin #12;Motivation No other chip based optical Similar to: Doping of Semiconductor 3 #12;4 Photonic Crystal Bio-Chemical Sensors Loncar et al, Appl. Phys

  4. Electromagnetic space-time crystals. II. Fractal computational approach

    E-Print Network [OSTI]

    G. N. Borzdov

    2014-10-20

    A fractal approach to numerical analysis of electromagnetic space-time crystals, created by three standing plane harmonic waves with mutually orthogonal phase planes and the same frequency, is presented. Finite models of electromagnetic crystals are introduced, which make possible to obtain various approximate solutions of the Dirac equation. A criterion for evaluating accuracy of these approximate solutions is suggested.

  5. Large area 3D helical photonic crystals A. K. Rauba)

    E-Print Network [OSTI]

    New Mexico, University of

    of helical structures (3D photonic crystals) using a simple, parallel, large-area lithography processLarge area 3D helical photonic crystals A. K. Rauba) and S. R. J. Brueckb) Center for High, enabling a high index contrast chiral meta- material. Optical transmission measurements of these helical

  6. On Polarization Of The Beam Extracted With The Bent Crystal

    E-Print Network [OSTI]

    M. N. Ukhanov

    2007-02-23

    Particles scattered off the nuclear target acquire a polarization if the nuclei have a non zero analyzing power. This effect is enhanced when particles traverse a bent crystal. Such enhancement under certain assumptions allows one to measure the analyzing power at the level of 10^-4 at the square of transfer momentum |t| bent crystal.

  7. 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.

  8. 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.

  9. How does a thermal binary crystal break under shear?

    E-Print Network [OSTI]

    Tobias Horn; Hartmut Löwen

    2014-11-21

    When exposed to strong shearing, the particles in a crystal will rearrange and ultimately, the crystal will break by forming large nonaffine defects. Even for the initial stage of this process, only little effort has been devoted to the understanding of the breaking process on the scale of the individual particle size for thermalized mixed crystals. Here, we explore the shear-induced breaking for an equimolar two-dimensional binary model crystal with a high interaction asymmetry between the two different species such that the initial crystal has an intersecting square sublattice of the two constituents. Using Brownian dynamics computer simulations, we show that the combination of shear and thermal fluctuations leads to a characteristic hierarchical breaking scenario where initially, the more strongly coupled particles are thermally distorted, paving the way for the weakly coupled particles to escape from their cage. This in turn leads to mobile defects which may finally merge, proliferating a cascade of defects, which triggers the final breakage of the crystal. This scenario is in marked contrast to the breakage of one-component crystals close to melting. Moreover, we explore the orientational dependence of the initial shear direction relative to the crystal orientation and compare this to the usual melting scenario without shear. Our results are verifiable in real-space experiments of superparamagnetic colloidal mixtures at a pending air-water interface in an external magnetic field where the shear can be induced by an external laser field.

  10. Thermal radiation in photonic crystals Marian Florescu,1,2,

    E-Print Network [OSTI]

    Dowling, Jonathan P.

    Thermal radiation in photonic crystals Marian Florescu,1,2, * Kurt Busch,3 and Jonathan P. Dowling2 2007; published 17 May 2007 We analyze the properties of thermal radiation in photonic crystals. In addition, we show that the central quantity that deter- mines these thermal radiation characteristics

  11. Fast-Response Infrared Ferroelectric Liquid Crystal Phase Modulators

    E-Print Network [OSTI]

    Wu, Shin-Tson

    Fast-Response Infrared Ferroelectric Liquid Crystal Phase Modulators Ju-Hyun Lee Yung-Hsun Wu Shin (about 2.3p at k ¼ 1.55 lm under E ¼ 2.5 V=lm) and fast response time ( at an infrared wavelength, say k ¼ 1.55 mm. On the contrary, ferroelectric liquid crystals (FLCs) show very fast

  12. Switchable Fresnel lens using polymer-stabilized liquid crystals

    E-Print Network [OSTI]

    Wu, Shin-Tson

    volts with fast response time. Such a device works well for a linearly polarized light. 2003 Optical-terminal adaptive Nematic liquid-crystal lens device," Opt. Lett. 19, 1013-1015 (1994). 6. A. F. Naumov, M. Yu. Loktev, I. R. Guralnik, and G. Vdovin, "Liquid-crystal adaptive lenses with modal control," Opt. Lett. 23

  13. On thermodynamics of crystal plasticity V.L. Berdichevsky

    E-Print Network [OSTI]

    Berdichevsky, Victor

    On thermodynamics of crystal plasticity V.L. Berdichevsky Mechanical Engineering, Wayne State; Plasticity theory; Dislocation theory 1. Introduction Thermodynamics is a theory of the slow variables of very complex systems. The goals of thermodynamics of crystal plasticity are to identify the slow

  14. Hydrogen plasma enhanced crystallization of hydrogenated amorphous silicon films

    E-Print Network [OSTI]

    Hydrogen plasma enhanced crystallization of hydrogenated amorphous silicon films K. Pangal,a) J. C August 1998; accepted for publication 21 October 1998 We report that a room temperature hydrogen plasma thermal crystallization of amorphous silicon time by a factor of five. Exposure to hydrogen plasma reduces

  15. Fast-response nematic liquid-crystal mixtures Sebastian Gauza

    E-Print Network [OSTI]

    Wu, Shin-Tson

    , response time, photostability. 1 Introduction The continuous demand for faster electro-optic response timesFast-response nematic liquid-crystal mixtures Sebastian Gauza Chien-Hui Wen Benjamin Wu Shin implies a fast response time of the described liquid crystals was observed. Using the new UCF mixture

  16. Crystal engineering of zeolites with graphene Paul Gebhardt,a

    E-Print Network [OSTI]

    Elliott, James

    - dimensional materials to engineer functional inorganic crystals. Introduction The morphology of zeolite that affect crystal synthesis.9­11 Zeolites are microporous materials widely used in industrial catalytic uncover a simple new method for controlling the synthesis of zeolitic materials and, through

  17. Real-time Dynamic Optimization of Batch Crystallization Processes

    E-Print Network [OSTI]

    Van den Hof, Paul

    process. The seeded fed-batch crystallizer is represented by a nonlinear moment model. An optimal controlReal-time Dynamic Optimization of Batch Crystallization Processes Ali Mesbah, , Alex N. Kalbasenka-time implementations of the proposed strategy reveal the effectiveness of closed-loop optimal control

  18. Low-loss guided modes in photonic crystal waveguides

    E-Print Network [OSTI]

    @fisicavolta.unipv.it Abstract: We study disorder-induced propagation losses of guided modes in photonic crystal slabs with line-defects. Meade, and J. N. Winn, Photonic Crystals: Molding the Flow of Light (Princeton University Press. Takahashi, and I. Yokohama, "Structural tuning of guiding modes of line-defect waveguides of Silicon

  19. Switchable Fresnel lens using polymer-stabilized liquid crystals

    E-Print Network [OSTI]

    Wu, Shin-Tson

    Switchable Fresnel lens using polymer-stabilized liquid crystals Yun-Hsing Fan, Hongwen Ren@mail.ucf.edu http:/lcd.creol.ucf.edu Abstract: A switchable Fresnel zone plate lens is demonstrated using a polymer controllable liquid crystal Fresnel lens," Proc. SPIE 1168, 352-357 (1989). 2. J. S. Patel and K. Rastani

  20. Reflection of focused beams from opal photonic crystals

    E-Print Network [OSTI]

    Jonsson, Fredrik

    Reflection of focused beams from opal photonic crystals Karri Varis, Marco Mattila Optoelectronics from opals that are synthesized using polystyrene and poly(methyl methacrylate) microspheres. © 2005 of self-organized opal photonic crystals," Phys. Rev. E 61, 5784­5793 (2000). 12. M. Bardosova and R. H

  1. Anisotropic elasticity in confocal studies of colloidal crystals

    E-Print Network [OSTI]

    Schindler, M

    2011-01-01

    We consider the theory of fluctuations of a colloidal solid observed in a confocal slice. For a cubic crystal we study the evolution of the projected elastic properties as a function of the anisotropy of the crystal using numerical methods based on the fast Fourier transform. In certain situations of high symmetry we find exact analytic results for the projected fluctuations.

  2. A Smooth Interface Method for Simulating Liquid Crystal Colloid Dispersions

    E-Print Network [OSTI]

    A Smooth Interface Method for Simulating Liquid Crystal Colloid Dispersions Ryoichi Yamamoto is presented for mesoscopic simulations of particle dispersions in liquid crystal solvents. It allows efficient mediated by the solvents. Demonstrations have been performed for the aggregation of colloid dispersions

  3. Three-dimensional wave propagation through single crystal solidliquid interfaces

    E-Print Network [OSTI]

    Wadley, Haydn

    Three-dimensional wave propagation through single crystal solid­liquid interfaces Yichi Lua solid­ liquid interfaces during single crystal growth. A previously developed two-dimensional ray across solid­liquid interfaces in cylindrical bodies where the receiver is located at an arbitrary

  4. 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.

  5. 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.

  6. 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.

  7. Simulations of electron channeling in bent silicon crystal

    E-Print Network [OSTI]

    Sushko, G B; Korol, A V; Greiner, Walter; Solov'yov, A V; Polozkov, R G; Ivanov, V K

    2013-01-01

    We report on the results of theoretical simulations of the electron channeling in a bent silicon crystal. The dynamics of ultra-relativistic electrons in the crystal is computed using the newly developed part [1] of the MBN Explorer package [2,3], which simulates classical trajectories of in a crystalline medium by integrating the relativistic equations of motion with account for the interaction between the projectile and crystal atoms. A Monte Carlo approach is employed to sample the incoming electrons and to account for thermal vibrations of the crystal atoms. The electron channeling along Si(110) crystallographic planes are studied for the projectile energies 195--855 MeV and different curvatures of the bent crystal.

  8. Polymer crystal-melt interfaces and nucleation in polyethylene

    E-Print Network [OSTI]

    Scott T. Milner

    2010-09-22

    Kinetic barriers cause polymers to crystallize incompletely, into nanoscale lamellae interleaved with amorphous regions. As a result, crystalline polymers are full of crystal-melt interfaces, which dominate their physical properties. The longstanding theoretical challenge to understand these interfaces has new relevance, because of accumulating evidence that polymer crystals often nucleate via a metastable, partially ordered "rotator" phase. To test this idea requires a theory of the bulk and interfacial free energies of the critical nucleus. We present a new approach to the crystal-melt interface, which represents the amorphous region as a grafted brush of loops in a self-consistent pressure field. We combine this theory with estimates of bulk free energy differences, to calculate nucleation barriers and rates via rotator versus crystal nuclei for polyethylene. We find rotator-phase nucleation is indeed favored throughout the temperature range where nucleation is observed. Our methods can be extended to other polymers.

  9. 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.

  10. 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.

  11. Nuclear Magnetic Resonance Quantum Computing Using Liquid Crystal Solvents

    E-Print Network [OSTI]

    Costantino S. Yannoni; Mark H. Sherwood; Lieven M. K. Vandersypen; Dolores C. Miller; Mark G. Kubinec; Isaac L. Chuang

    1999-12-12

    Liquid crystals offer several advantages as solvents for molecules used for nuclear magnetic resonance quantum computing (NMRQC). The dipolar coupling between nuclear spins manifest in the NMR spectra of molecules oriented by a liquid crystal permits a significant increase in clock frequency, while short spin-lattice relaxation times permit fast recycling of algorithms, and save time in calibration and signal-enhancement experiments. Furthermore, the use of liquid crystal solvents offers scalability in the form of an expanded library of spin-bearing molecules suitable for NMRQC. These ideas are demonstrated with the successful execution of a 2-qubit Grover search using a molecule ($^{13}$C$^{1}$HCl$_3$) oriented in a liquid crystal and a clock speed eight times greater than in an isotropic solvent. Perhaps more importantly, five times as many logic operations can be executed within the coherence time using the liquid crystal solvent.

  12. 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 1200°C. 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.

  13. Hydrodynamic Correlations slow down Crystallization of Soft Colloids

    E-Print Network [OSTI]

    Roehm, Dominic; Arnold, Axel

    2013-01-01

    Crystallization is often assumed to be a quasi-static process that is unaffected by details of particle transport other than the bulk diffusion coefficient. Therefore colloidal suspensions are frequently argued to be an ideal toy model for experimentally more difficult systems such as metal melts. In this letter, we want to challenge this assumption. To this aim, we have considered molecular dynamics simulations of the crystallization in a suspension of Yukawa-type colloids. In order to investigate the role of hydrodynamic interactions (HIs) mediated by the solvent, we modeled the solvent both implicitly and explicitly, using Langevin dynamics and the fluctuating Lattice Boltzmann method, respectively. Our simulations show a dramatic reduction of the crystal growth velocity due to HIs even at moderate hydrodynamic coupling. A detailed analysis shows that this slowdown is due to the wall-like properties of the crystal surface, which reduces the colloidal diffusion towards the crystal surface by hydrodynamic sc...

  14. Glassy Dislocation Dynamics in 2-D Colloidal Dimer Crystals

    E-Print Network [OSTI]

    Sharon J. Gerbode; Umang Agarwal; Desmond C. Ong; Chekesha M. Liddell; Fernando Escobedo; Itai Cohen

    2010-08-11

    Although glassy relaxation is typically associated with disorder, here we report on a new type of glassy dynamics relating to dislocations within 2-D crystals of colloidal dimers. Previous studies have demonstrated that dislocation motion in dimer crystals is restricted by certain particle orientations. Here, we drag an optically trapped particle through such dimer crystals, creating dislocations. We find a two-stage relaxation response where initially dislocations glide until encountering particles that cage their motion. Subsequent relaxation occurs logarithmically slowly through a second process where dislocations hop between caged configurations. Finally, in simulations of sheared dimer crystals, the dislocation mean squared displacement displays a caging plateau typical of glassy dynamics. Together, these results reveal a novel glassy system within a colloidal crystal.

  15. Thermal diffuse scattering from colloidal crystals Paul A. Rundquist, R. Kesavamoorthy,a) S. Jagannathan, and Sanford A. Asherb)

    E-Print Network [OSTI]

    Asher, Sanford A.

    Thermal diffuse scattering from colloidal crystals Paul A. Rundquist, R. Kesavamoorthy,a) S and thermal diffusescatteringfrom colloidal crystals consistingof aqueoussuspensionsof polystyrenesphereswith absorbingcolloidal crystals. In addition, we show that thermal diffusescatteringfrom colloidal crystals may

  16. PLASTIC DEFORMATION OF CRYSTALS: ANALYTICAL AND COMPUTER SIMULATION STUDIES OF DISLOCATION GLIDE

    E-Print Network [OSTI]

    Altintas, Sabri

    2011-01-01

    in Rate Processes in Plastic Deformation of Materials, J. C.PLASTIC DEFORMATION OF CRYSTALS: ANALYTICAL AND COMPUTERCAPTIONS FIGURES - iii - PLASTIC DEFORMATION OF CRYSTALS:

  17. 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.

  18. Field renormalization in Photonic Crystal waveguides

    E-Print Network [OSTI]

    Colman, P

    2015-01-01

    A novel strategy is introduced in order to include variations of the nonlinearity into the nonlinear schrodinger Equation. This technique, which relies on renormalization, is in particular well adapted to nanostructured optical systems where the nonlinearity exhibits large variations up to two orders of magnitude larger than in bulk material. We show that it takes into account in a simple and efficient way the specificity of the nonlinearity in nanostructures that is determined by geometrical parameters like the effective mode area and the group index. The renormalization of the nonlinear schrodinger Equation is the occasion for physics oriented considerations and unveils the potential of Photonic Crystal waveguides for the study of new nonlinear propagation phenomena.

  19. 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.

  20. Pulsed pyroelectric crystal-powered gamma source

    SciTech Connect (OSTI)

    Chen, A. X.; Antolak, A. J.; Leung, K.-N.; Raber, T. N.; Morse, D. H. [Sandia National Laboratories, Livermore, CA 94550 (United States)

    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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. Single crystal Processing and magnetic properties of gadolinium nickel

    SciTech Connect (OSTI)

    Shreve, Andrew John [Ames Laboratory

    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.

  7. 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.

  8. Demodulation of a positron beam in a bent crystal channel

    E-Print Network [OSTI]

    Kostyuk, A; Solov'yov, A V; Greiner, W

    2011-01-01

    The evolution of a modulated positron beam in a planar crystal channel is investigated within the diffusion approach. A detailed description of the formalism is given. A new parameter, the demodulation length, is introduced, representing the quantitative measure of the depth at which the channelling beam preserves its modulation in the crystal. It is demonstrated that there exist crystal channels with the demodulation length sufficiently large for using the crystalline undulator as a coherent source of hard X rays. This finding is a crucial milestone in developing a new type of lasers radiating in the hard X ray and gamma ray range.

  9. 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.

  10. 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.

  11. 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.

  12. Emission properties of radiative chiral nematic liquid crystals

    E-Print Network [OSTI]

    Mavrogordatos, Themistoklis

    2015-01-06

    the fluorescence characteristics from a † I.P. Il'chishin, E.A. Tikhonov, V.G. Tishchenko and M.T. Shpak, Generation of a tunable radiation by impurity cholesteric liquid crystals, JETP Lett., Vol. 32, 24-27 (1980). x xi dye-doped chiral nematic LC in the region... nematic crystal is determined by the specification of the director n alongside the usual quantities (mass density ?, pressure p and velocity v) for a liquid. In equi- librium, a nematic liquid crystal at rest under no external forces (including the forces...

  13. Elastic octopoles and colloidal structures in nematic liquid crystals

    E-Print Network [OSTI]

    S. B. Chernyshuk; O. M. Tovkach; B. I. Lev

    2013-05-14

    We propose a simple theoretical model which explains a formation of dipolar 2D and 3D colloidal structures in nematic liquid crystal. Colloidal particles are treated as effective hard spheres interacting via their elastic dipole, quadrupole and octopole moments. It is shown that octopole moment plays an important role in the formation of 2D and 3D nematic colloidal crystals. We generalize this assumption on the case of the external electric field and theoretically explain a giant electrostriction effect in 3D crystals observed recently [A. Nych et al., Nature Communications \\textbf{4}, 1489 (2013)].

  14. Colloidal crystal growth at externally imposed nucleation clusters

    E-Print Network [OSTI]

    Sven van Teeffelen; Christos N. Likos; Hartmut Löwen

    2008-02-15

    We study the conditions under which and how an imposed cluster of fixed colloidal particles at prescribed positions triggers crystal nucleation from a metastable colloidal fluid. Dynamical density functional theory of freezing and Brownian dynamics simulations are applied to a two-dimensional colloidal system with dipolar interactions. The externally imposed nucleation clusters involve colloidal particles either on a rhombic lattice or along two linear arrays separated by a gap. Crystal growth occurs after the peaks of the nucleation cluster have first relaxed to a cutout of the stable bulk crystal.

  15. 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.

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

    Energy Savers [EERE]

    Alabama. Built with all the amenities you would expect in a traditional home, the 250-square-foot structure will be used to educate contractors, businesses, and students about...

  17. Tiny magnets could work in sensors, information encoding

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

    of actinide isotopes present in the environment. Illustration of a binary neutron star system in the process of merging. The remnant formed by this merger could be...

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

    Office of Science (SC) Website

    was thought that only the nuclei of large atoms such as gold would have enough matter and energy to produce a primordial soup of matter's most basic "quark" and "gluon" building...

  19. FRONTS -Foundations of Adaptive Networked Societies of Tiny Artefacts

    E-Print Network [OSTI]

    Kröller, Alexander

    act- ing in a dynamic environment. This includes designing dif- ferent mathematical models beyond, or water flows. Finally, some nodes may actively move around to in- vestigate events, help bridging- tures, including enabling security by developing appro- pria

  20. Tiny but Toxic: How Industrial Waste Infiltrates the Body

    E-Print Network [OSTI]

    Lew, Rachel

    2015-01-01

    since declines in city pollution levels have been shown toin highly polluted cities, pollution levels must be reportedpollution and mortality: extended follow-up of the Harvard Six Cities

  1. 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...

  2. Tamil Nadu Small and Tiny Industries Association TANSTIA | Open Energy

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page| Open Energy Information Serbia-Enhancing CapacityVectren)ModelTalbotts Ltd Jump to:Tallmadge,Information Small

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

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-Inspired Solar FuelTechnologyTel:February 25, 2015 |7 TimelineDeclercknuclear

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

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust, High-Throughput AnalysisSinkhole Officials Turn toRandallFormallyWave-EnergyGets

  5. Tiny magnets could work in sensors, information encoding

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With U.S.Week DayDr.Theories81 to 1990 Timeline of

  6. Measuring Tiny Waves with High Power Particle Beams | Princeton Plasma

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformationJesse BergkampCentermillion Measurement of Muon Neutrino and AntineutrinoHome

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

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE: Alternative Fuelsof EnergyAprilEnergyPartnership for EnergyPetroleumZeroEnergy

  8. 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.

  9. Measurements of Snow Crystal Growth Dynamics in a Free-fall Convection Chamber

    E-Print Network [OSTI]

    Libbrecht, Kenneth G.

    Measurements of Snow Crystal Growth Dynamics in a Free-fall Convection Chamber Kenneth G. Libbrecht example of this phenomenon is the formation of snow crystals, which are ice crystals that grow from water vapor in an inert background gas. Although this is a relatively simple physical system, snow crystals

  10. 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

  11. A Simple Application of Fuzzy Arithmetic to Automate the Alignment of a Crystal in Channeling Experiments

    E-Print Network [OSTI]

    Ruiz-Sanchez, F J; Crespo-Sosa, A

    1999-01-01

    A Simple Application of Fuzzy Arithmetic to Automate the Alignment of a Crystal in Channeling Experiments

  12. Phase Change Enthalpies and Entropies of Liquid Crystals William E. Acree, Jr.a...

    E-Print Network [OSTI]

    Chickos, James S.

    Phase Change Enthalpies and Entropies of Liquid Crystals William E. Acree, Jr.a... Department The thermochemical behavior of more than 3000 organic compounds known to form liquid crystals is reported along.1063/1.1901689 Key words: fusion enthalpy; fusion entropy; liquid crystals; liquid crystal compendium; phase

  13. Self-assembly of three-dimensional photonic-crystals with air-core line defects

    E-Print Network [OSTI]

    is a colloidal crystal film that is grown on a silicon or glass substrate patterned with photoresist lines, and the 3D photonic crystal with air-core line defects is obtained by infiltrating the colloidal crystal the self-assembly of colloidal micro- spheres.5­11 Though the currently available colloidal crystals do

  14. Supplementary information to "Phonons in two-dimensional soft colloidal crystals"

    E-Print Network [OSTI]

    Schindler, Michael

    Supplementary information to "Phonons in two-dimensional soft colloidal crystals" Ke Chen et al. S1. Characterization of colloidal crystals. Colloidal crystals are characterized by sample lattice structure. Figure S1 of low frequency modes obtained from pristine colloidal crystals exhibit features of plane waves

  15. Colloidal Crystals Grown on Patterned By Mathieu Allard, Edward H. Sargent,

    E-Print Network [OSTI]

    Sargent, Edward H. "Ted"

    Colloidal Crystals Grown on Patterned Surfaces** By Mathieu Allard, Edward H. Sargent, Patrick C. Lewis, and Eugenia Kumacheva* The realization of photonic crystals based on colloidal crys- tal growth of the crystal.[8±10] Recently, colloidal crystallization has been accomplished on substrates patterned

  16. Effect of disorder on the optical properties of colloidal crystals Rajesh Rengarajan and Daniel Mittleman*

    E-Print Network [OSTI]

    Natelson, Douglas

    Effect of disorder on the optical properties of colloidal crystals Rajesh Rengarajan and Daniel Colloidal crystals offer a promising route for the formation of three-dimensional photonic crystals in colloidal crystal optics. Here, we report a systematic and quantitative study of disorder in colloidal

  17. Electro-optic response and switchable Bragg diffraction for liquid crystals in colloid-templated materials

    E-Print Network [OSTI]

    Electro-optic response and switchable Bragg diffraction for liquid crystals in colloid on self- assembled colloids. We compare the electro-optic responses of liquid crystal imbibed into colloid-templated polymers, liquid crystal imbibed in the interstitial space of colloid crystals, and conventional polymer

  18. Trapped nonneutral plasmas, liquids, and crystals (the thermal equilibrium states)

    E-Print Network [OSTI]

    California at San Diego, University of

    to the cryogenic temperature range, where liquid and crystal-like states are realized. The authors discuss plasma 121 2. Correlation energy 123 3. Free energy, the freezing transition, and correlation pressure

  19. Carbon Nanotube-Reinforced Thermotropic Liquid Crystal Polymer Nanocomposites

    E-Print Network [OSTI]

    Kim, Jun Young

    This paper focuses on the fabrication via simple melt blending of thermotropic liquid crystal polyester (TLCP) nanocomposites reinforced with a very small quantity of modified carbon nanotube (CNT) and the unique effects ...

  20. Effective material properties in twinned ferroelectric crystals Jiri Erharta)

    E-Print Network [OSTI]

    Cao, Wenwu

    Effective material properties in twinned ferroelectric crystals Jiri´ Erharta) and Wenwu Caob symmetry and effective material properties resulting from different twinning configurations. Numerical. INTRODUCTION The macroscopic material properties of a multidomain ferroelectric system are the collective

  1. Crystallization process development and spherical agglomerates for pharmaceutical processing applications

    E-Print Network [OSTI]

    Quon, Justin (Justin Louie)

    2013-01-01

    The control of crystallization steps is essential in the production of many materials in the pharmaceutical, materials, and chemical industries. Additionally, due to increasing costs of research and development, reductions ...

  2. PHOTOCATALYTIC AND PHOTOELECTROCHEMICAL HYDROGEN PRODUCTION ON STRONTIUM TITANATE SINGLE CRYSTALS

    E-Print Network [OSTI]

    Wagner, F.T.

    2012-01-01

    20 torr. \\>Jhen only the water filter was used the crystal44°C. With only the water filter in place, the bulk Resultsfilters. 'UV+Visible'=water filter only. Figure 5. Rate of

  3. Healing of defects in a two-dimensional granular crystal

    E-Print Network [OSTI]

    Rice, Marie C

    2014-01-01

    Using a macroscopic analog for a two dimensional hexagonal crystal, we perform an experimental investigation of the self-healing properties of circular grain defects with an emphasis on defect orientation. A circular grain ...

  4. Photonic Crystal Slot Waveguide Spectrometer for Detection of Methane

    E-Print Network [OSTI]

    Texas at Austin, University of

    Photonic Crystal Slot Waveguide Spectrometer for Detection of Methane 1 Funded by Environmental-infrared absorption spectrum of methane at 1665.5nm. · Guided mode design in SOI wafer #12;9 Device Fabrication Steps

  5. 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.

  6. Dynamics of Defect Motion in Nematic Liquid Crystal Flow: Modeling ...

    E-Print Network [OSTI]

    2007-08-02

    Liquid crystal is often viewed as the fourth state of the matter besides the gas, liquid and solid .... Thus, it is natural to look at the deformation tensor F associated.

  7. High-pressure stability relations, crystal structures, and physical...

    Office of Scientific and Technical Information (OSTI)

    High-pressure stability relations, crystal structures, and physical properties of perovskite and post-perovskite of NaNiFsub 3 Citation Details In-Document Search Title:...

  8. Confocal microscopy study of colloidal sedimentation and crystallization 

    E-Print Network [OSTI]

    Beckham, Richard Edward

    2009-05-15

    Colloidal crystallization in sedimenting systems is an incompletely understood process, where the influence of interparticle forces on the three-dimensional (3-D) microstructure remains to be fully elucidated. This ...

  9. 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.

  10. Planar channeling and quasichanneling oscillations in a bent crystal

    E-Print Network [OSTI]

    Sytov, A I; Bandiera, L; Germogli, G; Guidi, V; Mazzolari, A; Tikhomirov, V V

    2015-01-01

    Particles passing through a crystal under planar channeling experience transverse oscillations in their motion. As channeled particles approach the atomic planes of a crystal, they are likely to be dechanneled. This effect was used in ion-beam analysis with MeV energy. We studied this effect in a bent crystal for positive and negative particles within a wide range of energies in sight of application of such crystals at accelerators. We found the conditions for the appearance or not of channeling oscillations. Indeed a new kind of oscillations, strictly related to the motion of over-barrier particles, i.e. quasichanneling particles, has been predicted. Such oscillations, named planar quasichanneling oscillations, possess a different nature than channeling oscillations. Through computer simulation, we studied this effect and provided a theoretical interpretation for them. We show that channeling oscillations can be observed only for positive particles while quasichanneling oscillations can exist for particles w...

  11. Experimental techniques for deflection and radiation studies with bent crystals

    E-Print Network [OSTI]

    Hasan, Said

    2011-01-01

    What happens when a high energy charged particle crosses an amorphous material? It loses energy by ionization and its trajectory is affected by the multiple Coulomb scattering, being these phenomena originated by uncorrelated collisions with the atoms. If the atoms of the target were distributed according to an ordered scheme, the uncorrelated collisions would turn into a coherent interaction with the whole atomic structure. This is the case of an aligned crystal that, depending on the orientation, is seen as a set of atomic planes or strings by the impinging particles. Planes and strings produce potential wells able to confine the charged particles in a transversal region of the crystal, in the so called channeling condition, so that, bending the crystal, particles are forced to follow the curvature, being deflected. This simple and powerful idea, dating 1979, is at the basis of many theoretical and experimental studies that have proven bent crystals effectiveness, described their possible applications and ...

  12. Improvements of the crystal routine for collimation studies

    E-Print Network [OSTI]

    Mirarchi, D; Scandale, W; Taratin, A M; Yazynin, I

    2014-01-01

    A routine has been implemented to simulate interactions of protons with bent crystals in the collimation version of SixTrack. This routine is optimized in view of producing high-statistics tracking simulations of collimation cleaning assisted by bent crystals. Fine tuning and comparisons with experimental data of coherent effects which a particle can experience in a bent crystal have been carried out. The data taken with 400 GeV beams at the CERN-SPS North Area in the framework of the UA9 experiment are used to benchmark the routine. Further checks on low probability interactions have been made, leading to significant improvements in the description of interactions with crystals. Comparisons with other simulations tools are used to increase our confidence in the scaling to higher energies.

  13. Molecular Dynamics Simulation of Homogeneous Crystal Nucleation in Polyethylene

    E-Print Network [OSTI]

    Yi, Peng

    Using a realistic united-atom force field, molecular dynamics simulations were performed to study homogeneous nucleation of the crystal phase at about 30% supercooling from the melts of n-pentacontahectane (C150) and a ...

  14. 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.

  15. 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.

  16. FORMATION OF COLLOIDAL CRYSTALS FROM NANOPARTICLE STABILIZED COLLOIDAL SUSPENSIONS

    E-Print Network [OSTI]

    Braun, Paul

    FORMATION OF COLLOIDAL CRYSTALS FROM NANOPARTICLE STABILIZED COLLOIDAL SUSPENSIONS BY WENDY WOONYEE.....................................................................8 2.2 Colloid Stability in Suspension .......................................................................................9 2.3 Nanoparticle-Stabilized Colloidal Suspensions...............................................13

  17. The effects of capillarity on photonic crystal selective emitters

    E-Print Network [OSTI]

    Peykov, Daniel

    2014-01-01

    Photonic crystals offer an unparalleled control over optical properties and are ideal candidates as high efficiency selective emitters. They are, however, known to degrade at elevated temperatures through a number of ...

  18. Synthesis and physical characterization of thermoelectric single crystals

    E-Print Network [OSTI]

    Porras Pérez Guerrero, Juan Pablo

    2012-01-01

    There is much current interest in thermoelectric devices for sustainable energy. This thesis describes a research project on the synthesis and physical characterization of thermoelectric single crystals. 1In?Se?-[delta] ...

  19. Comment on "Single Crystals of Single-Walled Carbon Nanotubes

    E-Print Network [OSTI]

    Natelson, Douglas

    Comment on "Single Crystals of Single-Walled Carbon Nanotubes Formed by Self-Assembly" Schlittler) by the thermolysis of nano- patterned structures of alternating layers of C60 and nickel. Electron diffraction, high

  20. 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...

  1. Broadband super-collimation in a hybrid photonic crystal structure

    E-Print Network [OSTI]

    Hamam, Rafif E.

    We propose a two dimensional (2D) photonic crystal (PhC) structure that supports super-collimation over a large frequency range (over 4 times that of a traditional square lattice of holes). We theoretically and numerically ...

  2. Electro-optical Modulation in Graphene Integrated Photonic Crystal Nanocavities

    E-Print Network [OSTI]

    Gan, Xuetao

    We demonstrate high-contrast electro-optic modulation in a graphene integrated photonic crystal nanocavity, providing a modulation depth of more than 10 dB at telecom wavelengths. This work shows the feasibility of ...

  3. Curvature-directed Crystallization of Polymer Dielectrics in Nanopores 

    E-Print Network [OSTI]

    Reid, Dariya

    2013-11-26

    The formation of isotactic poly(propylene) (iPP) and polycarbonate (PC) nanowires of tunable diameter was demonstrated by melt-wetting the polymer into nanoporous anodic alumina. The crystallization process was analyzed using differential scanning...

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

    Office of Scientific and Technical Information (OSTI)

    (22.1 keV) x-rays, produced by petawatt class laser pulses interacting with a Kr gas jet and a silver foil, to measure the integrated crystal reflectivity of flat Highly...

  5. Design of polymeric substrates for controlled molecular crystallization

    E-Print Network [OSTI]

    Diao, Ying, Ph.D. Massachusetts Institute of Technology

    2012-01-01

    It is essential to control crystallization in many areas of science and technology, such as the production of pharmaceuticals, pigments, concrete, semiconductors, as well as the formation of biominerals. In most practical ...

  6. Theoretical Aspects of Liquid Crystals and Liquid Crystalline Polymers

    E-Print Network [OSTI]

    Feng, James J.

    Theoretical Aspects of Liquid Crystals and Liquid Crystalline Polymers James J. Feng Department theories and mole- cular theories separately. In addition, a theory for liquid crystalline materials has, Vancouver, British Columbia, Canada INTRODUCTION Liquid crystallinity refers to an intermediate state

  7. Hybrid Graphene Nematic Liquid Crystal Light Scattering Device

    E-Print Network [OSTI]

    Qasim, M. M.; Khan, A. A.; Kostanyan, A.; Kidambi, P. R.; Cabrero-Vilatela, A.; Braeuninger-Weimer, P.; Gardiner, D. J.; Hofman, S.; Wilkinson, T. D.

    2015-08-05

    A hybrid graphene nematic liquid crystal (LC) light scattering device is presented. This device exploits the inherent poly-crystallinity of chemical vapour deposited (CVD) graphene films to induce directional anchoring and formation of LC multi...

  8. Ordering Control of Self-Assembled Colloidal Crystals

    E-Print Network [OSTI]

    Koh, Yaw Koon

    Colloidal crystals are 3D nanostructures formed by self assembly of nanoparticles in suspension. The interaction forces between the colloid particles are expected to affect the ordering and the defect density in the resultant ...

  9. Crystallization Kinetics of Colloidal Spheres under Stationary Shear Flow

    E-Print Network [OSTI]

    P. Holmqvist; M. P. Lettinga; J. Buitenhuis; J. K. G. Dhont

    2005-08-29

    A systematic experimental study of dispersions of charged colloidal spheres is presented on the effect of steady shear flow on nucleation and crystal-growth rates. In addition, the non-equilibrium phase diagram as far as the melting line is concerned is measured. Shear flow is found to strongly affect induction times, crystal growth rates and the location of the melting line. The main findings are that (i) the crystal growth rate for a given concentration exhibits a maximum as a function of the shear rate, (ii) contrary to the monotonous increase of the growth rate with increasing concentration in the absence of flow, a maximum of the crystal growth rate as a function of concentration is observed for sheared systems, and (iii) the induction time for a given concentration exhibits a maximum as a function of the shear rate. These findings will be partly explained on a qualitative level.

  10. Reversible Attraction-Mediated Colloidal Crystallization on Patterned Substrates 

    E-Print Network [OSTI]

    Fernandes, Gregory

    2009-05-15

    In this dissertation we used tunable particle-particle and particle-substrate attraction to achieve reversible two-dimensional crystallization of colloids on homogeneous and patterned substrates. Total internal reflection and video microscopy...

  11. Computation of the scattering properties of nonspherical ice crystals 

    E-Print Network [OSTI]

    Zhang, Zhibo

    2004-11-15

    This thesis is made up of three parts on the computation of scattering properties of nonspherical particles in the atmosphere. In the first part, a new crystal type-droxtal-is introduced to make a better representation of ...

  12. Smectic Liquid Crystals in Random Environments

    E-Print Network [OSTI]

    Leo Radzihovsky; John Toner

    1999-06-04

    We study smectic liquid crystals in random environments, e.g., aerogel. A low temperature analysis reveals that even arbitrarily weak quenched disorder (i.e., arbitrarily low aerogel density) destroys translational (smectic) order. A harmonic approximation to the elastic energy suggests that there is no ``smectic Bragg glass'' phase in this system: even at zero temperature, it is riddled with dislocation loops induced by the quenched disorder. This result implies the destruction of orientational (nematic) order as well, and that the thermodynamically sharp Nematic-Smectic-A transition is destroyed by disorder, in agreement with recent experimental results. We also show that the anharmonic elastic terms neglected in the above treatment are important (i.e., are ``relevant'' in the renormalization group sense); whether they alter the above conclusions about the smectic Bragg glass, orientational disorder, and the existence of sharp transitions, remains an open question. However, they do not alter our conclusion that translational (smectic) order is always destroyed. In contrast, we expect that weak annealed disorder should have no qualitative effects on the smectic order.

  13. 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.

  14. Process analysis of margarine and tablespread crystallization operations 

    E-Print Network [OSTI]

    Garfield, Gary Charles

    1990-01-01

    of crystal networking in the fat (deMan et a1?1989). The use of nuclear magnetic resonance will likely replace other methods for solids determination as NMR equipment becomes more widespread. 2. RheologyfI'exture Measureinent The structure and rheological...PROCESS ANALYSIS OF MARGARINE AND TABLESPREAD CRYSTALLIZATION OPERATIONS A Thesis by GARY CHARLES GARFIELD Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirement for the degree...

  15. 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.

  16. 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.

  17. 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.

  18. The wave impedance of an atomically thin crystal

    E-Print Network [OSTI]

    Merano, Michele

    2015-01-01

    I propose an expression for the electromagnetic wave impedance of a two-dimensional atomic crystal, and I deduce the Fresnel coefficients in terms of this quantity. It is widely known that a two-dimensional crystal can absorb light, if its conductivity is different from zero. It is less emphasized that they can also store a certain amount of electromagnetic energy. The concept of impedance is useful to quantify this point.

  19. Crystallization of polyethylene by modified weighted density approximation(MWDA)

    E-Print Network [OSTI]

    Razeghizadeh, Alireza; Lavafpour, Farhad

    2015-01-01

    In this article, we use the modified weighted density approximation to study the crystallization of polyethylene. We also use a direct correlation function of polyethylene based on RISM theory. The free energy of a polyethylene is calculated using density functional theory. The crystallization and solid and liquid density are calculated and finally compared with the prism simulation and experimental results. That shown the result obtained by MWDA is in better agreement, compared with the experimental result than the prism.

  20. Crystallization of polyethylene by modified weighted density approximation(MWDA)

    E-Print Network [OSTI]

    Alireza Razeghizadeh; Vahdat Rafee; Farhad Lavafpour

    2015-02-07

    In this article, we use the modified weighted density approximation to study the crystallization of polyethylene. We also use a direct correlation function of polyethylene based on RISM theory. The free energy of a polyethylene is calculated using density functional theory. The crystallization and solid and liquid density are calculated and finally compared with the prism simulation and experimental results. That shown the result obtained by MWDA is in better agreement, compared with the experimental result than the prism.