WorldWideScience

Sample records for crystal extraction experiments

  1. What did we learn from the extraction experiments with bent crystals at the CERN SPS?

    CERN Document Server

    Elsener, K; Gyr, Marcel; Herr, Werner; Klem, J T; Mikkelsen, U; Weisse, E

    1998-01-01

    The feasibility and properties of particle extraction from an accelerator by means of a bent crystal were studied extensively at the CERN SPS. The main results of the experiments are presented. This includes the evidence for multipass extraction of heavy ions. These results are compared with theoretical expectations and computer simulations.

  2. Proton and Pb ion beam extraction experiments with bent crystals at the CERN-SPS

    CERN Document Server

    Elsener, K; Klem, J T; CERN. Geneva. SPS and LEP Division

    1997-01-01

    Extraction of particle beams from the CERN-SPS using bent silicon crystals is described. A summary of the early results is given. Emphasis is on the recent experiments, in particular on the energy dependence of proton extraction at 14, 120 and 270 GeV. 'U-shaped' crystals of different thickness and with a different miscut angle have been compared at 120 GeV. Non-linear excitation of the beam was used in one experiment, with the aim to achieve larger impact parameters - the results show a particular behaviour in the tails of the beam. Finally, the first experimental result on extraction of a 22 TeV fully stripped Pb ion beam with a bent crystal is also described.

  3. Crystal extraction at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Carrigan, Richard A., Jr.; /Fermilab

    2005-06-01

    Luminosity-driven channeling extraction was observed for the first time in a 900 GeV study at the Fermilab Tevatron carried out in the 1995-1996 period. This experiment, Fermilab E853, demonstrated that useful TeV level beams can be extracted from a superconducting accelerator during high luminosity collider operations without unduly affecting the background at the collider detectors. Multipass extraction was found to increase the efficiency of the process significantly. The beam extraction efficiency was in the range of 25%. The history of the experiment is reviewed. Special attention is paid to results related to collimation.

  4. Proton extraction from the CERN SPS using bent silicon crystals

    Science.gov (United States)

    Elsener, K.; Fidecaro, G.; Gyr, M.; Herr, W.; Klem, J.; Mikkelsen, U.; Møller, S. P.; Uggerhøj, E.; Vuagnin, G.; Weisse, E.

    1996-10-01

    The extraction of high energy particles from a circular accelerator by means of channeling in bent crystals is an attractive alternative to classical extraction schemes, in particular for high energy proton colliders where a classical scheme becomes expensive and incompatible with normal operation. This paper reviews the ongoing extraction experiments at the CERN-SPS with bent silicon crystals. It describes the principles of beam extraction by means of a bent crystal and the different extraction schemes used: first- and multi-pass extraction and the methods to create diffusion. The limitations in tuning the accelerator to the desired impact parameters and crucial items concerning crystal preparation, bending and pre-alignment are discussed. The experimental procedures including an overview of the detection of circulating and extracted beam are given. Finally, the paper summarizes the results of these experiments together with ideas for future developments.

  5. Pattern information extraction from crystal structures

    OpenAIRE

    Okuyan, Erhan

    2005-01-01

    Cataloged from PDF version of article. Determining crystal structure parameters of a material is a quite important issue in crystallography. Knowing the crystal structure parameters helps to understand physical behavior of material. For complex structures, particularly for materials which also contain local symmetry as well as global symmetry, obtaining crystal parameters can be quite hard. This work provides a tool that will extract crystal parameters such as primitive vect...

  6. Crystal activation experiment MA-151

    Science.gov (United States)

    Trombka, J. I.; Eller, E. L.; Schmadebeck, R. L.; Dyer, C. S.; Reedy, R. C.; Barr, D. W.; Gilmore, J. S.; Prestwood, R. J.; Bayhurst, B. P.; Perry, D. G.

    1976-01-01

    The crystal activation experiment consisted of two sample packages that were flown in the command module and returned to earth for analysis of the radioactivity induced in them during the flight. The objective of the experiment was to define the background caused by detector activation that interferes when gamma radiation is measured in the 0.02- to 10-megaelectronvolt range from earth orbit. Preliminary results show that the activation of the NaI(Tl) crystal was a factor of 3 below that from a similar measurement on Apollo 17. The identification of certain species and the level of activation observed show an important contribution from the interactions of thermal and energetic neutrons produced as secondaries in the spacecraft. That the activation was reduced by only a factor of 3 compared with the Apollo 17 experiment, despite the geomagnetically shielded orbit, possibly indicates more efficient secondary neutron production by the more energetic cosmic rays.

  7. Pattern information extraction from crystal structures

    Science.gov (United States)

    Okuyan, Erhan; Güdükbay, Uğur; Gülseren, Oğuz

    2007-04-01

    Determining the crystal structure parameters of a material is an important issue in crystallography and material science. Knowing the crystal structure parameters helps in understanding the physical behavior of material. It can be difficult to obtain crystal parameters for complex structures, particularly those materials that show local symmetry as well as global symmetry. This work provides a tool that extracts crystal parameters such as primitive vectors, basis vectors and space groups from the atomic coordinates of crystal structures. A visualization tool for examining crystals is also provided. Accordingly, this work could help crystallographers, chemists and material scientists to analyze crystal structures efficiently. Program summaryTitle of program: BilKristal Catalogue identifier: ADYU_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADYU_v1_0 Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland Licensing provisions: None Programming language used: C, C++, Microsoft .NET Framework 1.1 and OpenGL Libraries Computer: Personal Computers with Windows operating system Operating system: Windows XP Professional RAM: 20-60 MB No. of lines in distributed program, including test data, etc.:899 779 No. of bytes in distributed program, including test date, etc.:9 271 521 Distribution format:tar.gz External routines/libraries: Microsoft .NET Framework 1.1. For visualization tool, graphics card driver should also support OpenGL Nature of problem: Determining crystal structure parameters of a material is a quite important issue in crystallography. Knowing the crystal structure parameters helps to understand physical behavior of material. For complex structures, particularly, for materials which also contain local symmetry as well as global symmetry, obtaining crystal parameters can be quite hard. Solution method: The tool extracts crystal parameters such as primitive vectors, basis vectors and identify the space group from

  8. Carboxylic acids in crystallization of macromolecules: learning from successful crystallization experiments.

    Science.gov (United States)

    Offermann, Lesa R; He, John Z; Mank, Nicholas J; Booth, William T; Chruszcz, Maksymilian

    2014-03-01

    The production of macromolecular crystals suitable for structural analysis is one of the most important and limiting steps in the structure determination process. Often, preliminary crystallization trials are performed using hundreds of empirically selected conditions. Carboxylic acids and/or their salts are one of the most popular components of these empirically derived crystallization conditions. Our findings indicate that almost 40 % of entries deposited to the Protein Data Bank (PDB) reporting crystallization conditions contain at least one carboxylic acid. In order to analyze the role of carboxylic acids in macromolecular crystallization, a large-scale analysis of the successful crystallization experiments reported to the PDB was performed. The PDB is currently the largest source of crystallization data, however it is not easily searchable. These complications are due to a combination of a free text format, which is used to capture information on the crystallization experiments, and the inconsistent naming of chemicals used in crystallization experiments. Despite these difficulties, our approach allows for the extraction of over 47,000 crystallization conditions from the PDB. Initially, the selected conditions were investigated to determine which carboxylic acids or their salts are most often present in crystallization solutions. From this group, selected sets of crystallization conditions were analyzed in detail, assessing parameters such as concentration, pH, and precipitant used. Our findings will lead to the design of new crystallization screens focused around carboxylic acids.

  9. Maximizing Photoluminescence Extraction in Silicon Photonic Crystal Slabs.

    Science.gov (United States)

    Mahdavi, Ali; Sarau, George; Xavier, Jolly; Paraïso, Taofiq K; Christiansen, Silke; Vollmer, Frank

    2016-04-26

    Photonic crystal modes can be tailored for increasing light matter interactions and light extraction efficiencies. These PhC properties have been explored for improving the device performance of LEDs, solar cells and precision biosensors. Tuning the extended band structure of 2D PhC provides a means for increasing light extraction throughout a planar device. This requires careful design and fabrication of PhC with a desirable mode structure overlapping with the spectral region of emission. We show a method for predicting and maximizing light extraction from 2D photonic crystal slabs, exemplified by maximizing silicon photoluminescence (PL). Systematically varying the lattice constant and filling factor, we predict the increases in PL intensity from band structure calculations and confirm predictions in micro-PL experiments. With the near optimal design parameters of PhC, we demonstrate more than 500-fold increase in PL intensity, measured near band edge of silicon at room temperature, an enhancement by an order of magnitude more than what has been reported.

  10. Plasma crystals: experiments and simulation

    Science.gov (United States)

    Piel, A.

    2017-01-01

    Dusty plasmas are a well accessible system to study crystallization of charged-particle systems at room temperature. The large mass compared to atomic particles dramatically slows down the particle velocities. The high transparency of the system allows to trace simultaneously the motion of all particles with quasi-atomic resolution. After a brief overview, the progress in this field is exemplified by studies of spherical three-dimensional plasma crystals, the so-called Yukawa balls. The static structure and eigenmodes are explained in simple terms. It is shown that shielding modifies the expansion of a Yukawa ball from a self-similar explosion to a continuous ablation process that starts at the surface. The experimental progress with three-dimensional diagnostics and laser heating and sophisticated methods for visualising the order inside the shell structure are described. Together with quantifying the diffusion coefficient these investigations reveal the details of the solid-liquid phase transition. Besides thermodynamic aspects, the liquid phase of dusty plasmas also gives access to hydrodynamic phenomena at the individual particle scale.

  11. Vapor Crystal Growth (VCG) experiment Cell

    Science.gov (United States)

    1992-01-01

    The image shows a test cell of Crystal Growth experiment inside the Vapor Crystal Growth System (VCGS) furnace aboard the STS-42, International Microgravity Laboratory-1 (IML-1), mission. The goal of IML-1, a pressurized marned Spacelab module, was to explore in depth the complex effects of weightlessness of living organisms and materials processing. More than 200 scientists from 16 countires participated in the investigations.

  12. Lunar Magma Ocean Crystallization: Constraints from Fractional Crystallization Experiments

    Science.gov (United States)

    Rapp, J. F.; Draper, D. S.

    2015-01-01

    The currently accepted paradigm of lunar formation is that of accretion from the ejecta of a giant impact, followed by crystallization of a global scale magma ocean. This model accounts for the formation of the anorthosite highlands crust, which is globally distributed and old, and the formation of the younger mare basalts which are derived from a source region that has experienced plagioclase extraction. Several attempts at modelling the crystallization of such a lunar magma ocean (LMO) have been made, but our ever-increasing knowledge of the lunar samples and surface have raised as many questions as these models have answered. Geodynamic models of lunar accretion suggest that shortly following accretion the bulk of the lunar mass was hot, likely at least above the solidus]. Models of LMO crystallization that assume a deep magma ocean are therefore geodynamically favorable, but they have been difficult to reconcile with a thick plagioclase-rich crust. A refractory element enriched bulk composition, a shallow magma ocean, or a combination of the two have been suggested as a way to produce enough plagioclase to account for the assumed thickness of the crust. Recently however, geophysical data from the GRAIL mission have indicated that the lunar anorthositic crust is not as thick as was initially estimated, which allows for both a deeper magma ocean and a bulk composition more similar to the terrestrial upper mantle. We report on experimental simulations of the fractional crystallization of a deep (approximately 100km) LMO with a terrestrial upper mantle-like (LPUM) bulk composition. Our experimental results will help to define the composition of the lunar crust and mantle cumulates, and allow us to consider important questions such as source regions of the mare basalts and Mg-suite, the role of mantle overturn after magma ocean crystallization and the nature of KREEP

  13. MyCrystals - a simple visual data management program for laboratory-scale crystallization experiments

    DEFF Research Database (Denmark)

    Løvgreen, Monika Nøhr; Løvgreen, Mikkel; Christensen, Hans Erik Mølager

    2009-01-01

    MyCrystals is designed as a user-friendly program to display crystal images and list crystallization conditions. The crystallization conditions entry fields can be customized to suit the experiments. MyCrystals is also able to sort the images by the entered crystallization conditions, which...

  14. Liquid crystal interfaces: Experiments, simulations and biosensors

    Science.gov (United States)

    Popov, Piotr

    Interfacial phenomena are ubiquitous and extremely important in various aspects of biological and industrial processes. For example, many liquid crystal applications start by alignment with a surface. The underlying mechanisms of the molecular organization of liquid crystals at an interface are still under intensive study and continue to be important to the display industry in order to develop better and/or new display technology. My dissertation research has been devoted to studying how complex liquid crystals can be guided to organize at an interface, and to using my findings to develop practical applications. Specifically, I have been working on developing biosensors using liquid-crystal/surfactant/lipid/protein interactions as well as the alignment of low-symmetry liquid crystals for potential new display and optomechanical applications. The biotechnology industry needs better ways of sensing biomaterials and identifying various nanoscale events at biological interfaces and in aqueous solutions. Sensors in which the recognition material is a liquid crystal naturally connects the existing knowledge and experience of the display and biotechnology industries together with surface and soft matter sciences. This dissertation thus mainly focuses on the delicate phenomena that happen at liquid interfaces. In the introduction, I start by defining the interface and discuss its structure and the relevant interfacial forces. I then introduce the general characteristics of biosensors and, in particular, describe the design of biosensors that employ liquid crystal/aqueous solution interfaces. I further describe the basic properties of liquid crystal materials that are relevant for liquid crystal-based biosensing applications. In CHAPTER 2, I describe the simulation methods and experimental techniques used in this dissertation. In CHAPTER 3 and CHAPTER 4, I present my computer simulation work. CHAPTER 3 presents insight of how liquid crystal molecules are aligned by

  15. Decades of Data: Extracting Trends from Microgravity Crystallization History

    Science.gov (United States)

    Judge, R. A.; Snell, E. H.; Kephart, R.; vanderWoerd, M.

    2004-01-01

    The reduced acceleration environment of an orbiting spacecraft has been proposed as an ideal environment for biological crystal growth as the first sounding rocket flight in 1981 many crystallization experiments have flown with some showing improvement and others not. To further explore macromolecule crystal improvement in microgravity we have accumulated data from published reports and reports submitted by 63 missions including the Space Shuttle program, unmanned satellites, the Russian Space Station MIR and sounding rocket experiments. While it is not at this point in time a comprehensive record of all flight crystallization experimental results, there is however sufficient information for emerging trends to be identified. In this study the effects of the acceleration environment, the techniques of crystallization, sample molecular weight and the response of individual macromolecules to microgravity crystallization will be investigated.

  16. Extraction and Crystal Structure of Karounidiol

    Institute of Scientific and Technical Information of China (English)

    巢志茂; 王诚

    2003-01-01

    The title compound of karounidiol (C30H48O2), a main active triterpene component of snakegourd seed, was isolated from unsaponifiable matter of the seed oil of Trichosanthes kirilowii Maxim., and characterized by X-ray diffraction analysis. It crystallizes in orthorhombic system, space group P212121 with C30H48O2·CH3OH·H2O (C31H54O4), a = 7.515(1), b = 14.407(1), c = 27.799(2) (A。), V = 3009.8(5)(A。)3, Z = 4, Dx = 1.087 g/cm3, Mr = 490.77, F(000) = 1088 and μ = 0.086 mm-1. The final R = 0.0840 and wR = 0.2289 for 2752 observed reflections (|F|2 ≥ 2σ|F|2). The molecular crystal structure of karounidiol shows relative stereochemistry of (3α,13α,14β, 20α)-3,29-dihydroxy-13-methyl-26-norolean-7,9(11)-diene. The molecule is composed of five six- membered rings with ring junctures of A/B trans, C/D trans and D/E cis.

  17. Experience with intravascular lead extraction

    Institute of Scientific and Technical Information of China (English)

    MA Jian; TANG Kai; WANG Fang-zheng; ZHANG Shu; HUANG Cong-xin

    2005-01-01

    @@ With the increase of clinical use of cardiac pacemaker, a certain kinds of severe leads-related complications (especially infection) have presented in a few patients who underwent pacemaker implantation. The best way to manage this problem is to remove the transvenous leads.1,2 The technique for percutaneous removal of transvenous leads have undergone considerable development in western countries over the past 2 decades. However, there was scarce data on the application of this technique in China. This article reports the results of transvenous extraction of 171 permanent pacemaker leads with the standard lead extraction devices and intravascular countertraction technique during the period from January 1996 to May 2005 in the Center of Arrhythmia Diagnosis and Treatment, Fu Wai Hospital, Beijing, China.

  18. Pain experience after simple tooth extraction.

    Science.gov (United States)

    Al-Khateeb, Taiseer Hussain; Alnahar, Amir

    2008-05-01

    To assess pain experience after simple uncomplicated tooth extraction and to see if there is a need to prescribe analgesic drugs after such a procedure. A random sample of patients presenting for tooth extraction at the Maxillofacial Unit, Jordan University of Science and Technology was included. A baseline assessment of previously experienced general and dental pains using numeric scales was done. Subsequently, tooth extractions were done and telephone interviews were made during evenings for a week. Pain intensity was assessed on a numeric scale, and use of analgesic drugs and pain quality were recorded. At the evening of extraction 81.8% of patients had pain. Female gender predominance in pain reporting was statistically significant on postextraction days 3 and 5. Chronically inflamed teeth caused the highest mean pain intensity scores and nonsmokers showed significantly higher mean pain intensity scores compared with smokers. Mild pain was experienced by most patients (38.6%) on the evening of extraction. It was found that 55.3% of participants (largely females) used analgesic drugs on the evening of extraction, and 6.8% of participants still used analgesic drugs on day 7 postextraction. There was a significant correlation between mean pain intensity score and previous dental injection pain. Patients, notably females, experienced pain of varying intensity after simple uncomplicated tooth extraction maximally at the evening of extraction; and greater than 50% of the patients used analgesic drugs. We recommend offering regular analgesic drugs during the first week after tooth extraction.

  19. Extracting trends from two decades of microgravity macromolecular crystallization history

    Science.gov (United States)

    Judge, Russell A.; Snell, Edward H.; van der Woerd, Mark J.

    2005-01-01

    Since the 1980s hundreds of macromolecular crystal growth experiments have been performed in the reduced acceleration environment of an orbiting spacecraft. Significant enhancements in structural knowledge have resulted from X-ray diffraction of the crystals grown. Similarly, many samples have shown no improvement or degradation in comparison to those grown on the ground. A complex series of interrelated factors affect these experiments and by building a comprehensive archive of the results it was aimed to identify factors that result in success and those that result in failure. Specifically, it was found that dedicated microgravity missions increase the chance of success when compared with those where crystallization took place as a parasitic aspect of the mission. It was also found that the chance of success could not be predicted based on any discernible property of the macromolecule available to us.

  20. Recent results from the Crystal Barrel experiment

    Energy Technology Data Exchange (ETDEWEB)

    The Crystal Barrel Collaboration

    1991-10-09

    The Crystal Barrel experiment has been constructed and installed at the Low Energy Antiproton Ring (LEAR) at CERN. It has been fully operational since late 1989. In this talk, recent results of meson spectroscopy in p{bar p}-annihilations are presented. The main emphasis is on all-neutral annihilations, the study of the strange quark content of the proton, and the investigation of the decay mode of il particles. A 2{sup ++} resonance decaying into {pi}{degrees}{pi}{degrees}at a mass of 1515 {plus_minus} 10 MeV with a width of 120 {plus_minus} 10 MeV has been seen in a 3{pi}{degrees} final state.

  1. Recent results from the Crystal Barrel experiment

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-09

    The Crystal Barrel experiment has been constructed and installed at the Low Energy Antiproton Ring (LEAR) at CERN. It has been fully operational since late 1989. In this talk, recent results of meson spectroscopy in p[bar p]-annihilations are presented. The main emphasis is on all-neutral annihilations, the study of the strange quark content of the proton, and the investigation of the decay mode of il particles. A 2[sup ++] resonance decaying into [pi][degrees][pi][degrees]at a mass of 1515 [plus minus] 10 MeV with a width of 120 [plus minus] 10 MeV has been seen in a 3[pi][degrees] final state.

  2. Channeling of high-energy particles in bent crystals - Experiments at the CERN SPS

    Science.gov (United States)

    Baurichter, A.; Biino, C.; Clément, M.; Doble, N.; Elsener, K.; Fidecaro, G.; Freund, A.; Gatignon, L.; Grafström, P.; Gyr, M.; Hage-Ali, M.; Herr, W.; Keppler, P.; Kirsebom, K.; Klem, J.; Major, J.; Medenwaldt, R.; Mikkelsen, U.; Møller, S. P.; Siffert, P.; Uggerhøj, E.; Vilakazi, Z. Z.; Weisse, E.

    2000-04-01

    During the latest decade, experiments have been performed at the CERN SPS to investigate the use of high-energy channeled nuclei in bent crystals for extraction, beam splitting and beam bending. An understanding of channeling in a bent crystal with extraction and deflection efficiencies for different energies, crystal types and ions has been developed. Furthermore, the long-standing question of radiation damage has been addressed with encouraging outcome. This makes extrapolations possible for the construction of, e.g., an extraction device for the LHC at CERN, RHIC at Brookhaven or new splitting elements in high-energy beams.We present the main results obtained and discuss existing and future applications of bent crystals in high-energy physics.

  3. The second space experiment of protein crystallization with domestic facilities

    Institute of Scientific and Technical Information of China (English)

    王耀萍; 潘冀燊; 牛秀田; 周元聪; 华子千; 徐谦; 吴伸; 韩青; 李宏民; 刘延顺; 滕脉坤; 何海辉; 林胜祥; 毕汝昌

    1996-01-01

    The second experiment of protein crystallization was performed on domestic re-entry satelliteFSW-2 in 1994-07. The results are superior to the ones of the first mission in 1992: 9 of 10 different proteins were crystallized in space, and 70% of the total 48 samples yielded single crystals. Besides hen egg-white lysozyme which grew high-quality crystals on the first mission, an acidic phospholipase A2(aPLA2) from snake venom and hemoglobin from Anser Indicus produced good-quality crystals suitable for X-ray diffraction analyses. The positive effect of microgravity on protein crystal growth is verified again at this time.

  4. Optical experiments on 3D photonic crystals

    NARCIS (Netherlands)

    Koenderink, F.; Vos, W.

    2003-01-01

    Photonic crystals are optical materials that have an intricate structure with length scales of the order of the wavelength of light. The flow of photons is controlled in a manner analogous to how electrons propagate through semiconductor crystals, i.e., by Bragg diffraction and the formation of band

  5. An Experiment with Manifold Purposes: The Chemical Reactivity of Crystal Defects upon Crystal Dissolution.

    Science.gov (United States)

    Lazzarini, Annaluisa Fantola; Lazzarini, Ennio

    1983-01-01

    Background information and procedures are provided for an experiment designed to introduce (1) crystal defects and their reactivity upon crystal dissolution; (2) hydrates electron and its reactivity; (3) application of radiochemical method of analysis; and (4) the technique of competitive kinetics. Suggested readings and additional experiments are…

  6. Cavity QED experiments with ion Coulomb crystals

    DEFF Research Database (Denmark)

    Herskind, Peter Fønss; Dantan, Aurélien; Marler, Joan

    2009-01-01

    Cavity QED experimental results demonstrating collective strong coupling between ensembles of atomic ions cooled into Coulomb crystals and optical cavity fields have been achieved. Collective Zeeman coherence times of milliseconds have furthermore been obtained....

  7. Cavity QED experiments with ion Coulomb crystals

    DEFF Research Database (Denmark)

    Herskind, Peter Fønss; Dantan, Aurélien; Marler, Joan

    2009-01-01

    Cavity QED experimental results demonstrating collective strong coupling between ensembles of atomic ions cooled into Coulomb crystals and optical cavity fields have been achieved. Collective Zeeman coherence times of milliseconds have furthermore been obtained.......Cavity QED experimental results demonstrating collective strong coupling between ensembles of atomic ions cooled into Coulomb crystals and optical cavity fields have been achieved. Collective Zeeman coherence times of milliseconds have furthermore been obtained....

  8. submitter Light Extraction From Scintillating Crystals Enhanced by Photonic Crystal Structures Patterned by Focused Ion Beam

    CERN Document Server

    Modrzynski, Pawel; Knapitsch, Arno; Kunicki, Piotr; Lecoq, Paul; Moczala, Magdalena; Papakonstantinou, Ioannis; Auffray, Etiennette

    2016-01-01

    “Photonic Crystals (PhC)” have been used in a variety of fields as a structure for improving the light extraction efficiency from materials with high index of refraction. In previous work we already showed the light extraction improvement of several PhC covered LYSO crystals in computer simulations and practical measurements. In this work, new samples are made using different materials and techniques which allows further efficiency improvements. For rapid prototyping of PhC patterns on scintillators we tested a new method using “Focused Ion Beam (FIB)” patterning. The FIB machine is a device similar to a “Scanning Electron Microscope (SEM)”, but it uses ions (mainly gallium) instead of electrons for the imaging of the samples' surface. The additional feature of FIB devices is the option of surface patterning in nano-scale which was exploited for our samples. Three samples using FIB patterning have been produced. One of them is a direct patterning of the extraction face of a 0.8×0.8×10 $mm^3$ LYS...

  9. A Physical Chemistry Experiment in Polymer Crystallization Kinetics

    Science.gov (United States)

    Singfield, Kathy L.; Chisholm, Roderick A.; King, Thomas L.

    2012-01-01

    A laboratory experiment currently used in an undergraduate physical chemistry lab to investigate the rates of crystallization of a polymer is described. Specifically, the radial growth rates of typical disc-shaped crystals, called spherulites, growing between microscope glass slides are measured and the data are treated according to polymer…

  10. A Physical Chemistry Experiment in Polymer Crystallization Kinetics

    Science.gov (United States)

    Singfield, Kathy L.; Chisholm, Roderick A.; King, Thomas L.

    2012-01-01

    A laboratory experiment currently used in an undergraduate physical chemistry lab to investigate the rates of crystallization of a polymer is described. Specifically, the radial growth rates of typical disc-shaped crystals, called spherulites, growing between microscope glass slides are measured and the data are treated according to polymer…

  11. High efficiency multi-pass proton beam extraction with a bent crystal at the SPS

    Science.gov (United States)

    Altuna, X.; Bussa, M. P.; Carboni, G.; Dehning, B.; Elsener, K.; Ferrari, A.; Fidecaro, G.; Freund, A.; Guinand, R.; Gyr, M.; Herr, W.; Klem, J.; Laffin, M.; Lanceri, L.; Mikkelsen, U.; Møller, S. P.; Scandale, W.; Tosello, F.; Uggerhøj, E.; Vuagnin, G.; Weisse, E.; Weisz, S.

    1995-02-01

    Recent measurements of 120 GeV proton extraction by means of a bent silicon crystal at the CERN-SPS accelerator are summarized. The existence of multi-pass extraction has been proven by blocking first-pass extraction: using a crystal covered with an amorphous layer, extracted beam with high efficiency was observed, which provides a direct proof for the importance of the multi-pass mechanism. This opens new possibilities in the design and optimization of a bent crystal extraction scheme.

  12. Phoenito experiments: combining the strengths of commercial crystallization automation.

    Science.gov (United States)

    Newman, Janet; Pham, Tam M; Peat, Thomas S

    2008-11-01

    The use of crystallization robots for initial screening in macromolecular crystallization is well established. This paper describes how four general optimization techniques, growth-rate modulation, fine screening, seeding and additive screening, have been adapted for automation in a medium-throughput crystallization service facility. The use of automation for more challenging optimization experiments is discussed, as is a novel way of using both the Mosquito and the Phoenix nano-dispensing robots during the setup of a single crystallization plate. This dual-dispenser technique plays to the strengths of both machines.

  13. High-quality single crystals for neutron experiments

    Indian Academy of Sciences (India)

    Geetha Balakrishnan

    2008-10-01

    To make headway on any problem in physics, high-quality single crystals are required. In this talk, special emphasis will be placed on the crystal growth of various oxides (superconductors and magnetic materials), borides and carbides using the image furnaces at Warwick. The floating zone method of crystal growth used in these furnaces produces crystals of superior quality, circumventing many of the problems associated with, for example, flux growth from the melt. This method enables the growth of large volumes of crystal, a prerequisite especially for experiments using neutron beams. Some examples of experimental results from crystals grown at Warwick, selected from numerous in-house studies and our collaborative research projects with other UK and international groups will be discussed.

  14. Determination of the Surface Plasmons Polaritons extraction efficiency from a self-assembled plasmonic crystal

    CERN Document Server

    Frederich, Hugo; Laverdant, Julien; de Marcillac, Willy Daney; Schwob, Catherine; Coolen, Laurent; Maître, Agnès

    2013-01-01

    We experimentally measure and analytically describe the fluorescence enhancement obtained by depositing CdSe/CdS nanocrystals onto a gold plasmonic crystal, a two-dimensional grating of macroscopic size obtained by gold deposition on a self-assembled opal. We show evidences of nanocrystals near-field coupling to the gold Surface Plasmons Polaritons (SPP) followed by grating-induced SPP re-emission to far-field. We develop a theoretical framework and an original method in order to evaluate, from photoluminescence experiments, the SPP extraction efficiency of a grating.

  15. Deflection and Extraction of Pb Ions up to 33 TeV/c by a Bent Silicon Crystal

    Energy Technology Data Exchange (ETDEWEB)

    Arduini, G.; Biino, C.; Clement, M.; Cornelis, K.; Doble, N.; Elsener, K.; Ferioli, G.; Fidecaro, G.; Gatignon, L.; Grafstroem, P.; Gyr, M.; Herr, W.; Klem, J.; Mikkelsen, U.; Weisse, E. [SL Division, CERN, CH-1211 Geneva 23 (Switzerland); Mo/ller, S.P.; Uggerho/j, E. [ISA, Aarhus University (Denmark); Taratin, A. [JINR, Dubna (Russia); Freund, A. [ESRF, Grenoble (France); Keppler, P.; Major, J. [MPI fuer Metallforschung, Stuttgart (Germany)

    1997-11-01

    The first results from an experiment to deflect a beam of fully stripped, ultrarelativistic Pb{sup 82+} ions of 400 GeV/c per unit of charge, equivalent to 33 TeV/c , by means of a bent crystal are reported. Deflection efficiencies are as high as 14{percent}, in agreement with theoretical estimates. In a second experiment a bent crystal was used to extract 270 GeV/c -per-charge Pb{sup 82+} (22 TeV/c) ions from a coasting beam in the CERN-SPS, and a high extraction efficiency of up to 10{percent} was found. These represent the first measurements to demonstrate applications of bent crystals in high energy heavy ion beams. {copyright} {ital 1997} {ital The American Physical Society}

  16. Deflection and Extraction of Pb Ions up to 33 TeV/c by a Bent Silicon Crystal

    Science.gov (United States)

    Arduini, G.; Biino, C.; Clément, M.; Cornelis, K.; Doble, N.; Elsener, K.; Ferioli, G.; Fidecaro, G.; Gatignon, L.; Grafström, P.; Gyr, M.; Herr, W.; Klem, J.; Mikkelsen, U.; Weisse, E.; Møller, S. P.; Uggerhøj, E.; Taratin, A.; Freund, A.; Keppler, P.; Major, J.

    1997-11-01

    The first results from an experiment to deflect a beam of fully stripped, ultrarelativistic Pb82+ ions of 400 GeV/c per unit of charge, equivalent to 33 TeV/c, by means of a bent crystal are reported. Deflection efficiencies are as high as 14%, in agreement with theoretical estimates. In a second experiment a bent crystal was used to extract 270 GeV/c-per-charge Pb82+ \\(22 TeV/c\\) ions from a coasting beam in the CERN-SPS, and a high extraction efficiency of up to 10% was found. These represent the first measurements to demonstrate applications of bent crystals in high energy heavy ion beams.

  17. Skylab experiments on semiconductors and alkali halides. [single crystal growth

    Science.gov (United States)

    Lundquist, C. A.

    1974-01-01

    The space processing experiments performed during the Skylab missions included one on single crystal growth of germanium selenide and telluride, one on pure and doped germanium crystals, two on pure and doped indium antimonide, one on gallium-indium-antimony systems, and one on a sodium chloride-sodium fluoride eutectic. In each experiment, three ampoules of sample were processed in the multipurpose electric furnace within the Skylab Materials Processing Facility. All were successful in varying degrees and gave important information about crystal growth removed from the effects of earth surface gravity.

  18. Observation and comparative analysis of proton beam extraction or collimation by different planar channels of a bent crystal

    Directory of Open Access Journals (Sweden)

    A. G. Afonin

    2012-08-01

    Full Text Available In the experiment the efficiency of the 50 GeV proton beam extraction from accelerator by means of a bent crystal as a function of crystal orientation was measured. This allowed one to make a comparative analysis of efficiencies of high-energy protons deflection by different crystal atomic planes with different values of the electrostatic field. The results of simulation of high-energy protons deflection by means of crystal atomic planes and crystal atomic strings are also presented in the article. In the case of planar channeling the simulation shows a good agreement with experimental data. In the case of proton motion in the regime of stochastic scattering by bent atomic strings the simulation shows that angles of particle deflection are much greater than the critical channeling angle.

  19. On the energy dependence of proton beam extraction with a bent crystal

    CERN Document Server

    Arduini, Gianluigi; Fidecaro, Giuseppe; Gyr, Marcel; Herr, Werner; Klem, J T; Mikkelsen, U; Weisse, E

    1998-01-01

    Proton beam extraction from the CERN SPS by means of a bent silicon crystal is reported at three different energies, 14 GeV, 120 GeV and 270 GeV. The experimental results are compared to computer simulations which contain a sound model of the SPS accelerator as well as the channeling phenomena in bent crystals. The overall energy dependence of crystal assisted proton beam extraction is understood and provides the basis to discuss such a scheme for future accelerators.

  20. Possibility of high efficient beam extraction from the CERN SPS with a bent crystal. Simulation results

    Science.gov (United States)

    Scandale, W.; Kovalenko, A. D.; Taratin, A. M.

    2017-03-01

    The extraction of the SPS beam of 270 GeV/c protons assisted by a bent crystal was studied by simulation. Two methods for delivering the SPS beam onto a crystal were considered: transverse diffusion and orbit bump of the beam. It was shown that the main condition for high efficient beam extraction with a bent crystal, which is a small divergence of the incident beam, can be fulfilled. Extraction efficiency up to 99% can be reached for both methods of the beam delivering. The irradiation of the electrostatic septum wires during the beam extraction can be considerably reduced.

  1. Locating and Visualizing Crystals for X-Ray Diffraction Experiments.

    Science.gov (United States)

    Becker, Michael; Kissick, David J; Ogata, Craig M

    2017-01-01

    Macromolecular crystallography has advanced from using macroscopic crystals, which might be >1 mm on a side, to crystals that are essentially invisible to the naked eye, or even under a standard laboratory microscope. As crystallography requires recognizing crystals when they are produced, and then placing them in an X-ray, electron, or neutron beam, this provides challenges, particularly in the case of advanced X-ray sources, where beams have very small cross sections and crystals may be vanishingly small. Methods for visualizing crystals are reviewed here, and examples of different types of cases are presented, including: standard crystals, crystals grown in mesophase, in situ crystallography, and crystals grown for X-ray Free Electron Laser or Micro Electron Diffraction experiments. As most techniques have limitations, it is desirable to have a range of complementary techniques available to identify and locate crystals. Ideally, a given technique should not cause sample damage, but sometimes it is necessary to use techniques where damage can only be minimized. For extreme circumstances, the act of probing location may be coincident with collecting X-ray diffraction data. Future challenges and directions are also discussed.

  2. Interdisciplinary Chemistry Experiment: An Environmentally Friendly Extraction of Lycopene

    Science.gov (United States)

    Zhu, Jie; Zhang, Mingjie; Liu, Qingwei

    2008-01-01

    A novel experiment for the extraction of lycopene from tomato paste without the use of an organic solvent is described. The experiment employs polymer, green, and analytical chemistry. This environmentally friendly extraction is more efficient and requires less time than the traditional approach using an organic solvent. The extraction is…

  3. Photonic crystals to enhance light extraction from 2D materials

    CERN Document Server

    Noori, Yasir J; Roberts, Jonathan; Woodhead, Christopher; Bernardo-Gavito, Ramon; Tovee, Peter; Young, Robert J

    2016-01-01

    We propose a scheme for coupling 2D materials to an engineered cavity based on a defective rod type photonic crystal lattice. We show results from numerical modelling of the suggested cavity design, and propose using the height profile of a 2D material transferred on top of the cavity to maximise coupling between exciton recombination and the cavity mode. The photonic structure plays a key role in enhancing the launch efficiency, by improving the directionality of the emitted light to better couple it into an external optical system. When using the photonic structure, we measured an increase in the extraction ratio by a factor of 3.4. We investigated the variations in the flux spectrum when the radius of the rods is modified, and when the 2D material droops to a range of different heights within the cavity. We found an optimum enhancement when the rods have a radius equal to 0.165 times the lattice constant, this enhancement reduces when the radius is reduced or increased. Finally, we discuss the possible use...

  4. Neutron Transmission through Sapphire Crystals: Experiments and Simulations

    OpenAIRE

    Rantsiou, Emmanouela; Filges, Uwe; Panzner, Tobias; Klinkby, Esben Bryndt

    2013-01-01

    Sapphire crystals are excellent filters of fast neutrons, while at the same time exhibit moderate to very little absorption at smaller energies. We have performed an extensive series of measurements in order to quantify the above effect. Alongside our experiments, we have performed a series of simulations, in order to reproduce the transmission of cold neutrons through sapphire crystals. Thosesimulations were part of the effort of validating and improving the newly developed interface between...

  5. Light Extraction Enhancement of GaN LED with a Two-Dimensional Photonic Crystal Slab

    Institute of Scientific and Technical Information of China (English)

    LIU Hong-Wei; KAN Qiang; WANG Chun-Xia; HU Hai-Yang; XU Xing-Sheng; CHEN Hong-Da

    2011-01-01

    Light extraction effects of a photonic crystal slab with a micrometer scale lattice constant are studied. A GaN light emitting diode (LED) with a photonic crystal slab is fabricated. The light extraction effects and the enhancement mechanism are investigated. From theoretical analysis, it is found that the characteristics of LED light emission are modulated by the photonic crystal slab. Experimental results show that the LED light emission intensity is enhanced by 38% due to guide mode extracting by the photonic crystal.%@@ Light extraction effects ora photonic crystal slab with a micrometer scale lattice constant are studied.A GaN light emitting diode(LED) with a photonic crystal slab is fabricated.The light extraction effects and the enhancement mechanism are investigated.From theoretical analysis,it is found that the characteristics of LED light emission are modulated by the photonic crystal slab.Experimental results show that the LED light emission intensity is enhanced by 38% due to guide mode extracting by the photonic crystal.

  6. Extraction of 22 TeV/c Lead Ions from the CERN SPS using a Bent Silicon Crystal

    Science.gov (United States)

    Herr, W.; Elsener, K.; Fidecaro, G.; Gyr, M.; Klem, J.; Weisse, E.

    1997-05-01

    The extraction of protons from the halo of a circulating beam has been repeatedly demonstrated at the SPS. In a recent experiment a coasting lead ion beam was available at a momentum of 270 GeV/c/Z corresponding to a total momentum of 22 TeV/c per ion and the possibility to extract ultrarelativistic lead ions with a bent crystal could be demonstrated for the first time. We present the experimental challenges, the measurements performed during this experiment and the first results.

  7. Deflection and extraction of Pb ions up to 33 TeV/c by a bent silicon crystal

    CERN Document Server

    Arduini, Gianluigi; Clément, M; Cornelis, Karel; Doble, Niels T; Elsener, K; Ferioli, G; Fidecaro, Giuseppe; Freund, A; Gatignon, L; Grafström, P; Gyr, Marcel; Herr, Werner; Keppler, P; Klem, J T; Major, J V; Mikkelsen, U; Møller, S P; Taratin, A M; Uggerhøj, Erik; Weisse, E

    1997-01-01

    The first results from an experiment to deflect a beam of fully stripped, ulta-relativistic Pb ions of 400 GeV/c per unit of charge, equivalent to 33 TeV/c, by means of a bent crystal are reported. Deflection efficiencies are as high as 14%, in agreement with theoretical predictions. In a second experiment a bent crsytal was used to extract 270 GeV/c per charge Pb82+ (22 TeV/c) ions from a coasting beam in the CERN-SPS, and a high extraction efficiency of up to 10% was found. These represent the first measurements to demonstrate applications of bent crystals in high energy heavy ion beams.

  8. New results in meson spectroscopy from the crystal barrel experiment

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, C.A. [Carnegie Mellon Univ., Pittsburgh, PA (United States)

    1994-04-01

    Recent observations by the Crystal Barrel experiment of two scalar resonances, f{sub o}(1365) and a{sub o}(1450) have allowed the authors to clarify the members of the scalar nonet. In addition, a third scalar, f{sub o}(1500), appears to be supernumerary, and is a candidate for the scalar glueball expected near 1500 MeV.

  9. Improving Student Results in the Crystal Violet Chemical Kinetics Experiment

    Science.gov (United States)

    Kazmierczak, Nathanael; Vander Griend, Douglas A.

    2017-01-01

    Despite widespread use in general chemistry laboratories, the crystal violet chemical kinetics experiment frequently suffers from erroneous student results. Student calculations for the reaction order in hydroxide often contain large asymmetric errors, pointing to the presence of systematic error. Through a combination of "in silico"…

  10. Two crystal x-ray spectrometers for OMEGA experiments

    Science.gov (United States)

    Reverdin, C.; Casner, A.; Girard, F.; Lecherbourg, L.; Loupias, B.; Tassin, V.; Philippe, F.

    2016-11-01

    Two x-ray spectrometers have been built for x-ray spectroscopy of laser-produced plasmas on OMEGA at the Laboratory for Laser Energetics (LLE) by Commissariat a ̀ l'Energie Atomique et aux énergies alternatives (CEA). The accessible photon energy range is from 1.5 to 20 keV. The first spectrometer, called X-ray CEA Crystal Spectrometer with a Charge-Injection Device (XCCS-CID), records three spectra with three crystals coupled to a time integrated CID camera. The second one, called X-ray CEA Crystal Spectrometer (XCCS) with a framing camera, is time resolved and records four spectra with two crystals on the four frames of a framing camera. Cylindrical crystals are used in Johan geometry. Each spectrometer is positioned with a ten-inch manipulator inside the OMEGA target chamber. In each experiment, after choosing a spectral window, a specific configuration is designed and concave crystals are precisely positioned on a board with angled wedges and spacers. Slits on snouts enable 1D spatial resolution to distinguish spectra emitted from different parts of the target.

  11. On the energy dependence of proton beam extraction with a bent crystal

    Science.gov (United States)

    Arduini, G.; Elsener, K.; Fidecaro, G.; Gyr, M.; Herr, W.; Klem, J.; Mikkelsen, U.; Weisse, E.

    1998-03-01

    Proton beam extraction from the CERN SPS by means of a bent silicon crystal is reported at three different energies, 14 GeV, 120 GeV and 270 GeV. The experimental results are compared to computer simulations which contain a sound model of the SPS accelerator as well as the channeling phenomena in bent crystals. The overall energy dependence of crystal assisted proton beam extraction is understood and provides the basis to discuss such a scheme for future accelerators. © 1998

  12. Isolation and extraction of lucidin primeveroside from Rubia tinctorum L. and crystal structure elucidation.

    Science.gov (United States)

    Henderson, Robert L; Rayner, Christopher M; Blackburn, Richard S

    2013-11-01

    Madder (Rubia tinctorum L.) has been used as a dye for over 2000 years with alizarin and purpurin the major natural dyes analysed from extractions undertaken. The use of ethanol as the solvent in the extraction process produced an extract that yielded four anthraquinone compounds lucidin primeveroside, ruberythric acid, alizarin and lucidin-ω-ethyl ether. Gravitational separation of the extract was used to record the first crystal structure of lucidin primeveroside, which is also the first ever known crystal structure of a glycoside containing anthraquinone moiety. The crystal structure along with (1)H and (13)C NMR helped elucidate and confirm the structure of this overlooked natural dye which has been shown to be a major compound in R. tinctorum L.

  13. Proton extraction from the SPS with a bent crystal

    Science.gov (United States)

    Ferroni, F.; Akbari, H.; Altuna, X.; Bardin, S.; Bellazzini, R.; Biryukov, V.; Brez, A.; Bussa, M. P.; Busso, L.; Calcaterra, A.; Carboni, G.; Costantini, F.; De Sangro, R.; Elsener, K.; Ferioli, G.; Ferrari, A.; Ferri, G. P.; Ferroni, F.; Fidecaro, G.; Freund, A.; Guinand, R.; Gyr, M.; Herr, W.; Hilaire, A.; Jensen, B. N.; Klem, J.; Lanceri, L.; Maier, K.; Massai, M. M.; Mertens, V.; Moller, S. P.; Morganti, S.; Palamara, O.; Peraire, S.; Petrera, S.; Placidi, M.; Santacesaria, R.; Scandale, W.; Schmidt, R.; Taratin, A. M.; Tosello, F.; Uggerhoj, E.; Vetterman, B.; Vita, P. E.; Vuagnin, G.; Weisse, E.; Weisz, S.; RD22 Collaboration

    1994-11-01

    The RD22 Collaboration has performed several measurements on the extraction of protons from the CERN-SPS by planar channeling in bent silicon monocrystals. Extraction efficiencies of about 10% have been routinely achieved for a bending angle of 8.5 mrad with the SPS running at 120 GeV.

  14. First results on proton extraction from the CERN-SPS with a bent crystal

    Science.gov (United States)

    Akbari, H.; Altuna, X.; Bardin, S.; Bellazzini, R.; Biryukov, V.; Brez, A.; Bussa, M. P.; Busso, L.; Calcaterra, A.; Carboni, G.; Costantini, F.; de Sangro, R.; Elsener, K.; Ferioli, F.; Ferrari, A.; Ferri, G. P.; Ferroni, F.; Fidecaro, G.; Freund, A.; Guinand, R.; Gyr, M.; Herr, W.; Hilaire, A.; Jensen, B. N.; Klem, J.; Lanceri, L.; Maier, K.; Massai, M. M.; Mertens, V.; Møller, S. P.; Morganti, S.; Palamara, O.; Peraire, S.; Petrera, S.; Placidi, M.; Santacesaria, R.; Scandale, W.; Schmidt, R.; Taratin, A. M.; Tosello, F.; Uggerhøj, E.; Vettermann, B.; Vita, P. F.; Vuagnin, G.; Weisse, E.; Weisz, S.

    1993-09-01

    The feasibility of extracting protons from the halo of a high energy beam by means of a bent silicon crystal has been investigated. Protons diffusing from a GeV beam circulating in the SPS at CERN have been extracted at an angle of 8.5 mrad. Efficiencies of abour 10 percent, orders of magnitude higher than the values achieved previously, have been measured. The present results are promising in view of beam extraction from future multi-TeV proton accelerators.

  15. Optimization of light collection from crystal scintillators for cryogenic experiments

    Energy Technology Data Exchange (ETDEWEB)

    Danevich, F.A., E-mail: danevich@kinr.kiev.ua [Institute for Nuclear Research, MSP 03680, Kyiv (Ukraine); Kobychev, R.V. [Institute for Nuclear Research, MSP 03680, Kyiv (Ukraine); National Technical University of Ukraine “Kyiv Polytechnic Institute”, 03056 Kyiv (Ukraine); Kobychev, V.V. [Institute for Nuclear Research, MSP 03680, Kyiv (Ukraine); Kyungpook National University, Daegu 702-701 (Korea, Republic of); Kraus, H. [Department of Physics, University of Oxford, Keble Road, Oxford OX1 3RH (United Kingdom); Mikhailik, V.B. [Department of Physics, University of Oxford, Keble Road, Oxford OX1 3RH (United Kingdom); Diamond Light Source, Harwell Science Campus, Didcot, OX11 0DE (United Kingdom); Mokina, V.M. [Institute for Nuclear Research, MSP 03680, Kyiv (Ukraine)

    2014-04-21

    High light collection efficiency is an important requirement in any application of scintillation detectors. The purpose of this study is to investigate the possibility for improving this parameter in cryogenic scintillation bolometers, which can be considered as promising detectors in experiments investigating neutrinoless double beta decay and dark matter. Energy resolutions and relative pulse amplitudes of scintillation detectors using ZnWO{sub 4} scintillation crystals of different shapes (cylinder ∅ 20×20 mm and hexagonal prism with diagonal 20 mm and height 20 mm), reflector materials and shapes, optical contact and surface properties (polished and diffused) were measured at room temperature. Propagation of optical photons in these experimental conditions was simulated using Geant4 and ZEMAX codes. The results of the simulations are found to be in good agreement with each other and with direct measurements of the crystals. This could be applied to optimize the geometry of scintillation detectors used in the cryogenic experiments.

  16. Inhibition of Struvite Crystal Growth in the Presence of Herbal Extract Orthosiphon Aristatus BL.MIQ

    Directory of Open Access Journals (Sweden)

    Muryanto Stefanus

    2016-01-01

    Full Text Available The formation of urinary stones is a serious problem worldwide. Struvite (MgNH4PO4.6H2O is known as one of the main components of the stones. Traditionally, herbal extracts treatment is recommended. This paper discussestheeffects of Orthosiphon aristatus Bl.Miq leaves extract (OA on struvite crystals grown by diffusion gel method. After three weeks the crystals were separated from thegel, air dried and stored for characterisation. The crystals exhibit different morphologiesdepending upon the location of growth. It was found that OA caused the crystals to have noticeable surface defects, discolorisation and fragmentation. Also, OA (upto 5.0% decreased the growth rate. XRD analysis confirms struvite crystallinity. Pure crystals and those grown with OA showed identical XRD pattern, indicating that the crystalline nature may be unaffected. For crystals with OA, FTIR spectrum shifted to higher wave numbers, implying that the various organic compounds in OA might be absorbed on the crystal surface. TG-DTA studies showed similar thermal behaviour for both pure crystals and those with OA. However, the later revealed lowerendothermic temperature, indicating lower thermal stability. Fragmentationand lower thermal stability of struviteindicatedthat OA was a potent inhibitor of struvite and could be effective for urinary stone treatment.

  17. Determination of Other Related Carotenoids Substances in Astaxanthin Crystals Extracted from Adonis amurensis.

    Science.gov (United States)

    Zhang, Li-hua; Peng, Yong-jian; Xu, Xin-de; Wang, Sheng-nan; Yu, Lei-ming; Hong, Yi-min; Ma, Jin-ping

    2015-01-01

    Astaxanthin is a kind of important carotenoids with powerful antioxidation capacity and other health functions. Extracting from Adonis amurensis is a promising way to obtain natural astaxanthin. However, how to ensure the high purity and to investigate related substances in astaxanthin crystals are necessary issues. In this study, to identify possible impurities, astaxanthin crystal was first extracted from Adonis amurensis, then purified by saponification and separation. The concentration of total carotenoids in purified astaxanthin crystals was as high as 97% by weight when analyzed by UV-visible absorption spectra. After identified with TLC, HPLC and MS, besides free astaxanthin as main ingredient in the crystals, there existed four other unknown related substances, which were further investigated by HPLC/ESI/MS with the positive ion mode combining with other auxiliary reference data obtained in stress tests, at last it was confirmed that four related carotenoids substances were three structural isomers of semi-astacene and adonirubin.

  18. Extraction of the proton charge radius from experiments

    CERN Document Server

    Kelkar, N G; Nowakowski, M

    2016-01-01

    Static properties of hadrons such as their radii and other moments of the electric and magnetic distributions can only be extracted using theoretical methods and not directly measured from experiments. As a result, discrepancies between the extracted values from different precision measurements can exist. The proton charge radius, $r_p$, which is either extracted from electron proton elastic scattering data or from hydrogen atom spectroscopy seems to be no exception. The value $r_p = 0.84087(39)$ fm extracted from muonic hydrogen spectroscopy is about 4% smaller than that obtained from electron proton scattering or standard hydrogen spectroscopy. The resolution of this so called proton radius puzzle has been attempted in many different ways over the past six years. The present article reviews these attempts with a focus on the methods of extracting the radius.

  19. Extracting the temperature distribution on a phase-change memory cell during crystallization

    Science.gov (United States)

    Bakan, Gokhan; Gerislioglu, Burak; Dirisaglik, Faruk; Jurado, Zoila; Sullivan, Lindsay; Dana, Aykutlu; Lam, Chung; Gokirmak, Ali; Silva, Helena

    2016-10-01

    Phase-change memory (PCM) devices are enabled by amorphization- and crystallization-induced changes in the devices' electrical resistances. Amorphization is achieved by melting and quenching the active volume using short duration electrical pulses (˜ns). The crystallization (set) pulse duration, however, is much longer and depends on the cell temperature reached during the pulse. Hence, the temperature-dependent crystallization process of the phase-change materials at the device level has to be well characterized to achieve fast PCM operations. A main challenge is determining the cell temperature during crystallization. Here, we report extraction of the temperature distribution on a lateral PCM cell during a set pulse using measured voltage-current characteristics and thermal modelling. The effect of the thermal properties of materials on the extracted cell temperature is also studied, and a better cell design is proposed for more accurate temperature extraction. The demonstrated study provides promising results for characterization of the temperature-dependent crystallization process within a cell.

  20. High light-extraction-efficiency OLED based on photonic crystal slab structures with taper unit cells

    Institute of Scientific and Technical Information of China (English)

    YAN Rong-jin; WANG Qing-kang

    2006-01-01

    To improve the light-extraction-efficiency of OLED,we introduced PCS (Photonic Crystal Slab) structures into the interface of ITO layer and glass substrate.PCS structures with Taper unit cells are proved to be effective in reducing the energy of guided wave trapped in high refractive index material,and an increase of light-extraction-efficiency to 95.26% is gained.This enhancement is much greater than the traditional PCS with cylinder unit cells (60%-70%).Physical mechanisms of light-extraction-efficiency enhancement in these structures are further discussed.

  1. INHIBITION OF CALCIUM OXALATE CRYSTALLIZATION IN-VITRO BY VARIOUS EXTRACTS OF HYPTIS SUAVEOLENS (L. POIT.

    Directory of Open Access Journals (Sweden)

    Agarwal Kumkum

    2012-03-01

    Full Text Available Hyptis suaveolens (L Poit. commonly known as Vilayati tulsi, belongs to the Mint family Lamiaceae. The inhibition of in-vitro calcium-oxalate crystal (a major component of most urinary stones formation by various extracts of Hyptis was investigated by titrimetric method. The inhibitor potency of alcohol extracts of Hyptis suaveolens (L. Poit was found to be comparable to that of cystone (a proprietary drug for dissolving kidney stones. Thus alcohol extract could be further analyzed in vivo and further characterization of its active compound could lead to the discovery of a new candidate drug for the patients with urolithiasis.

  2. Growth Inhibition of Struvite Crystals in the Presence of Herbal Extract Boerhaavia diffusa Linn

    Directory of Open Access Journals (Sweden)

    C. K. Chauhan

    2009-01-01

    Full Text Available Problem statement: The formation of a urinary stone, known as nephrolithiasis, urolithiasis, renal calculi or kidney stone is a serious, debilitating problem in all societies throughout the world. Struvite or Ammonium Magnesium Phosphate Hexahydrate (AMPH is one of the components of urinary stone (calculi. Struvite stones are commonly found in women. Struvites form in humans as a result of urinary tract infection with ureolithic urea splitting micro organisms. These stones can grow rapidly forming "staghorn-calculi", which is more painful urological disorder. Therefore, it is of prime importance to study the growth and inhibition of Struvite crystals. Approach: This in vitro study had been carried out in the presence of herbal extract of Boerhaavia diffusa Linn. by using single diffusion gel growth technique. Sodium metasilicate solution of specific gravity 1.05 and an aqueous solution of ammonium dihydrogen phosphate of 0.5 M concentration were mixed so that the pH value 7.0 could be set. After the gelation, equal amount of supernatant solution of 1.0 M magnesium acetate prepared with 0.5 and 1% concentrations of the herbal extract of B. diffusa Linn. were gently poured on the set gels in the respective test tubes in the aseptic medium. Results: The growth of crystals without and with herbal extracts was monitored at regular time intervals. As the concentration of B. diffusa Linn. increased, the inhibition of crystals also increased in the gel media as well as the dissolution of crystals at the gel-liquid interface increases. The de-fragmentation of some grown crystals was also noticed. Conclusion: The herbal extract of B. diffusa Linn. inhibited the growth of struvite crystals in vitro. This study incorporated multidisciplinary interests and may be used for formulating the strategy for prevention or dissolution of urinary stones.

  3. Melt extraction from crystal mushes: Numerical model of texture evolution and calibration of crystallinity-ordering relationships

    Science.gov (United States)

    Špillar, Václav; Dolejš, David

    2015-12-01

    Mechanical crystal-melt interactions in magmatic systems by separation or accumulation of crystals or by extraction of interstitial melt are expected to modify the spatial distribution of crystals observed as phenocrysts in igneous rocks. Textural analysis of porphyritic products can thus provide a quantitative means of interpreting the magnitude of crystal accumulation or melt loss and reconstructing the initial crystal percentage, at which the process occurred. We present a new three-dimensional numerical model that evaluates the effects of crystal accumulation (or interstitial melt removal) on the spatial distribution of crystals. Both processes lead to increasing apparent crystallinity but also to increasing spatial ordering expressed by the clustering index (R). The trend of progressive crystal packing deviates from a random texture trend, produced by static crystal nucleation and growth, and it is universal for any texture with straight log-linear crystal size distribution. For sparse crystal suspensions (5 vol. % crystals, R = 1.03), up to 97% melt can be extracted, corresponding to a new crystallinity of 65 vol.% and R = 1.32, when the rheological threshold of crystal interlocking is reached. For initially crystal-rich suspensions, the compaction path is shorter, this is because the initial crystal population is more aggregated and it reaches the limit of interlocking sooner. Crystal suspensions with ~ 35 vol.% crystals cannot be compacted without mechanical failure. These results illustrate that the onset of the rheological threshold of magma immobility strongly depends on the spatial configuration of crystals in the mush: the primary rigid percolation threshold (~ 35 vol.% crystals) corresponds to touching or interlocking crystal framework produced by in situ closed-system crystallization, whereas the secondary rigid percolation threshold (~ 35 to ~ 75 vol.% crystals) can be reached by compaction, which is particularly spatially efficient when acting on

  4. Test~of~Beam~Extraction~by~Crystal~Channeling~at~the~SPS: A First Step towards a LHC Extracted Beam

    CERN Multimedia

    2002-01-01

    % RD22 \\\\ \\\\ The availability of a beam extracted out of the LHC accelerator would open up very interesting possibilities for B-physics, in particular for the study of CP-violation. Channeling in bent crystals appears to be the most promising method to produce an extracted beam of intensity $\\sim$~10$^{8}$ p/sec. This would provide as many as 10$^{10}$ $ B \\bar{B} $ pairs per year of run, two orders of magnitude more than could be produced by an e$^+$e$^-$ B-factory with L~=~10$^{34}$ cm$^{-2}$s$^{-1}$ We propose a R\\&D program to study beam extraction at the CERN SPS, using a silicon bent crystal to be installed in the SPS beam pipe and placed next to the beam in such a way as to intercept the beam halo. Transverse excitation of the beam in presence of non-linearities will be used to create halo conditions similar to what are expected for LHC.

  5. Optimal cuts to extract the third-order elastic constants of langasite single crystals.

    Science.gov (United States)

    Zhang, Haifeng

    2011-06-01

    Optimal cuts to determine the third-order elastic constants of langasite single crystals by the resonator method are proposed. By designing a small number of langasite resonators with optimal cut angles and measuring their force-frequency effects, the third-order elastic constants of langasite single crystals may be extracted separately. The numerical method to search for these optimal cut angles is presented. All 14 third-order elastic constants may be determined through a series of experimental measurements. This method will simplify traditional methods used to determine the third-order elastic constants and could potentially produce more accurate results.

  6. Growth inhibition of struvite crystals by the aqueous root extract of Rotula aquatica.

    Science.gov (United States)

    Chauhan, C K; Joshi, M J; Vaidya, A D B

    2011-06-01

    Formation of urinary stone is a serious and debilitating problem throughout the world. In the present study, the inhibitory effect of aqueous extract of root of Rotula aquatica was investigated against struvite crystals (one of the components of urinary stone) grown in vitro using single diffusion gel growth technique. For setting the gel, sodium metasilicate solution (specific gravity 1.05) and 0.5 M aqueous solution of ammonium dihydrogen phosphate were mixed, so that the pH of the mixture could be set at 7.0. Equal amounts of supernatant solution of magnesium acetate (1.0 M) prepared with 0.0%, 0.5% and 1% concentrations of the extract were gently poured on the set gels. It was observed that the number, dimension, total mass, total volume, growth rate and depth of growth of struvite crystals decreased with the increasing extract concentrations in the supernatant solutions. The enhancement of dissolution rate and fragmentation of struvite crystals suggested potential application of the extract for inhibition of struvite type urinary stone.

  7. Shock compression experiments on Lithium Deuteride single crystals.

    Energy Technology Data Exchange (ETDEWEB)

    Knudson, Marcus D.; Desjarlais, Michael Paul; Lemke, Raymond W.

    2014-10-01

    S hock compression exper iments in the few hundred GPa (multi - Mabr) regime were performed on Lithium Deuteride (LiD) single crystals . This study utilized the high velocity flyer plate capability of the Sandia Z Machine to perform impact experiments at flyer plate velocities in the range of 17 - 32 km/s. Measurements included pressure, density, and temperature between %7E200 - 600 GPa along the Principal Hugoniot - the locus of end states achievable through compression by large amplitude shock waves - as well as pressure and density of re - shock states up to %7E900 GPa . The experimental measurements are compared with recent density functional theory calculations as well as a new tabular equation of state developed at Los Alamos National Labs.

  8. Ampoule failure sensor development for semiconductor crystal growth experiments

    Science.gov (United States)

    Watring, Dale A.; Johnson, Martin

    1994-01-01

    Currently there are no devices to detect an ampoule failure in semiconductor crystal growth experiments. If an ampoule fails, it will go undetected until the containing cartridge is breached due to chemical degradation. The experiment will then be terminated resulting in a failed experiment and a loss of data. The objective of this research was to develop a reliable failure sensor that would detect a specific liquid or vapor material before the metallic cartridge is degraded and the processing furnace contaminated. The sensor is a chemical fuse made from a metal with which the semiconductor material reacts more rapidly than it does with the containing cartridge. Upon ampoule failure, the sensor is exposed to the vapor or liquid semiconductor and the chemical reaction causes a resistance change in the sensor material. The sensor shows a step change in resistance on the order of megohms when exposed to mercury zinc telluride (HgZnTe), mercury cadmium telluride (HgCdTe), or gallium arsenide (GaAs). This ampoule failure sensor is being tested for possible use on the second United States Microgravity Mission (USML-2) and is the subject of a NASA patent application.

  9. Carboxylic and dicarboxylic acids extracted from crushed magnesium oxide single crystals

    Science.gov (United States)

    Freund, F.; Gupta, A. D.; Kumar, D.

    1999-01-01

    Carboxylic and dicarboxylic acids (glycolic, oxalic, malonic and succinic) have been extracted with tetrahydrofuran (THF) and H2O from large synthetic MgO crystals, crushed to a medium fine powder. The extracts were characterized by infrared spectroscopy and 1H-NMR. The THF extracts were derivatized with tert-butyldimethylsilyl (t-BDMS) for GC-MS analysis. A single crystal separated from the extract was used for an x-ray structure analysis, giving the monoclinic unit cell, space group P21/c with ao = 5.543 A, bo = 8.845 A, co = 5.086 A, and beta = 91.9 degrees, consistent with beta-succinic acid, HOOC(CH2)COOH. The amount of extracted acids is estimated to be of the order of 0.1 to 0.5 mg g-1 MgO. The MgO crystals from which these organic acids were extracted grew from the 2860 degrees C hot melt, saturated with CO/CO2 and H2O, thereby incorporating small amounts of the gaseous components to form a solid solution (ss) with MgO. Upon cooling, the ss becomes supersaturated, causing solute carbon and other solute species to segregate not only to the surface but also internally, to dislocations and subgrain boundaries. The organic acids extracted from the MgO crystals after crushing appear to derive from these segregated solutes that formed C-C, C-H and C-O bonds along dislocations and other defects in the MgO structure, leading to entities that can generically be described as (HxCyOz)n-. The processes underlying the formation of these precursors are fundamental in nature and expected to be operational in any minerals, preferentially those with dense structures, that crystallized in H2O-CO2-laden environments. This opens the possibility that common magmatic and metamorphic rocks when weathering at the surface of a tectonically active planet like Earth may be an important source of abiogenically formed complex organic compounds.

  10. Extraction of the beta-factor for single quantum dots coupled to a photonic crystal waveguide

    DEFF Research Database (Denmark)

    Nielsen, Henri Thyrrestrup; Sapienza, Luca; Lodahl, Peter

    2010-01-01

    wavelength of single quantum dots is temperature tuned across the band edge of a photonic crystal waveguide and the spontaneous emission rate is recorded. Decay rates up to 5.7 ns−1, corresponding to a Purcell factor of 5.2, are measured and β-factors up to 85% are extracted. These results prove......We present measurements of the β-factor, describing the coupling efficiency of light emitted by single InAs/GaAs semiconductor quantum dots into a photonic crystal waveguide mode. The β-factor is evaluated by means of time resolved frequency-dependent photoluminescence spectroscopy. The emission...... the potential of photonic crystal waveguides in the realization of on-chip single-photon sources....

  11. Biaxial nematic liquid crystals theory, simulation and experiment

    CERN Document Server

    Luckhurst, Geoffrey R

    2015-01-01

    Liquid Crystals are a state of matter that have properties between those of conventional liquid and those of a solid crystal. Thermotropic liquid crystals react to changes in temperature or, in some cases, pressure. The reaction of lyotropic liquid crystals, which are used in the manufacture of soaps and detergents, depends on the type of solvent they are mixed with. Since the accidental discovery of the chiral nematic (ordered) phase in 1888 many liquid crystal phases have been found, sometimes by chance and sometimes by design. The existence of one such phase was predicted by Freiser in 197

  12. Bent crystal channeling applications for beam splitting, extraction and collimation in the U-70 accelerator of IHEP

    Energy Technology Data Exchange (ETDEWEB)

    Chesnokov, Yu.A., E-mail: chesnokov@ihep.ru; Afonin, A.G.; Baranov, V.T.; Britvich, G.I.; Chirkov, P.N.; Maisheev, V.A.; Terekhov, V.I.; Yazynin, I.A.

    2013-08-15

    The report presents an overview of the results of IHEP activity obtained during 1987-2012 in the field of studying and using bent crystals to steer high-energy particle beams. The hardware installed to study crystal beam splitting, collimation and extraction is described. It has been shown that the developed crystal deflectors are capable for sustaining long-term operation to deliver high-energy extracted beams for fixed-target physics. The first results on extraction of 24.1 GeV/nucleon carbon ions are also presented.

  13. Extraction and estimation of the quantity of calcium oxalate crystals in the foliage of conifer and hardwood trees.

    Science.gov (United States)

    Minocha, Rakesh; Chamberlain, Bradley; Long, Stephanie; Turlapati, Swathi A; Quigley, Gloria

    2015-05-01

    The main goal of this study was to develop a method for the extraction and indirect estimation of the quantity of calcium oxalate (CaOx) in the foliage of trees. Foliar tissue was collected from a single tree of each species (five conifers and five hardwoods) for comparison of extractions in different solvents using 10 replicates per species from the same pool of tissue. For each species, calcium (Ca) and oxalate were extracted sequentially in double deionized water and 2N acetic acid, and finally, five replicate samples were extracted in 5% (0.83N) perchloric acid (PCA) and the other five in 2N hydrochloric acid (HCl); three cycles of freezing and thawing were used for each solvent. Total ions were extracted by microwave digestion. Calcium was quantified with an inductively coupled plasma emission spectrophotometer method and oxalate was eluted and quantified using a high performance liquid chromatography method. This experiment was repeated again with two conifer and two hardwood species using four trees per species, and two analytical replicates for each tree. We report here that, regardless of age of individual trees within a species, time of collection or species type, the third extraction in PCA or HCl resulted in near equimolar quantities of Ca and oxalate (r(2) ≥ 0.99). This method provides an easy estimate of the quantity of CaOx crystals using a small sample of foliar tissue. An additional benefit of PCA is that it precipitates the nucleic acids and proteins, allowing the quantification of several free/soluble metabolites such as amino acids, polyamines, organic acids and inorganic elements all from a single sample extract.

  14. Crystal Clear - New crystals for LHC experiments help to improve PET scanners Exhibition LEPFest 2000

    CERN Multimedia

    2000-01-01

    Better resolution through smaller crystals Better images through higher light yieldHigh efficiency, stability and gain by using avalanche photodiodes and low noise electronics Reduced cost of crystals (1/10) through mass production

  15. Inhibition of crystallization of calcium oxalate by the extraction of Tamarix gallica L.

    Science.gov (United States)

    Bensatal, Ahmed; Ouahrani, M R

    2008-12-01

    The main objective is to study the inhibitor effect of acid fraction of the extract of Tamarix gallica L on the crystallization of calcium oxalate. The extract of Tamarix gallica L is very rich by acid compounds that are used as an inhibitor of nephrolithiasis (calcium oxalate). Our study of the calcium oxalate crystallization is based on the model of turbidimetry by means of a spectrophotometer. The calcium oxalate formation is induced by the addition of oxalate solutions of sodium and of calcium chloride. The addition of inhibitor with various concentrations enabled us to give information on the percentage of inhibition. The comparison between the turbidimetric slopes with and without inhibitor gives the effectiveness of inhibitor for the acid fraction. By comparing the photographs of with and without inhibitor, we concluded that the extract of Tamarix gallica L acts at the stage of growth. The acid fraction of the extract of Tamarix gallica L gives an activity remarkable in the formation of urinary lithiasis (calcium oxalate); this effectiveness is due to the presence of functions of acid.

  16. Enhancement of light extraction efficiency in OLED with two-dimensional photonic crystal slabs

    Institute of Scientific and Technical Information of China (English)

    Rongjin Yan; Qingkang Wang

    2006-01-01

    Light extraction efficiency of organic light emitting diode (OLED) based on various photonic crystal slab (PCS) structures was studied. By using the finite-difference time-domain (FDTD) method, we investigated the effect of several parameters, including filling factor and lattice constant, on the enhancement of light extraction efficiency of three basic PCSs, and got the most effective one. Two novel designs of "interlaced"and "double-interlaced" PCS structures based on the most effective basic PCS structure were introduced,and the "interlaced" one was proved to be even more efficient than its prototype. Large enhancement of light extraction efficiency resulted from the coupling to leaky modes in the expended light cone of a band structure, the diffraction in the space between columns, as well as the strong scattering at indium-tinoxide/glass interfaces.

  17. In vitro effect of hydro alcoholic extract of Adiantum capillus-veneris Linn. on calcium oxalate crystallization

    Directory of Open Access Journals (Sweden)

    Ajij Ahmed

    2013-01-01

    Full Text Available Background: Adiantum capillus-veneris Linn. is widely used in the management of urolithiasis in Unani system of medicine. Aim: To evaluate the effect of the hydro alcoholic extract of A. capillus-veneris Linn. on calcium oxalate crystallisation by in vitro study. Materials and Methods: The study includes crystallization, nucleation and aggregation assay. Crystallization was induced by addition of 50 μl of 0.1 M sodium oxalate in whole urine in the absence and the presence of extract at different concentrations (0.50 mg, 0.75 mg and 1 mg. The nucleation and aggregation rates were followed at 620 nm after mixing calcium chloride and sodium oxalate solution and in a buffered solution containing calcium oxalate monohydrate crystals, respectively. The rate was evaluated by comparing the slope of turbidity in the presence of extract with that of control using the spectrophotometer. Crystals in the urine were also analysed by light microscopy. Results and Conclusion: Extract of the test drug inhibited the crystallization in solution; less and smaller particles were observed in the presence of extract. These results were further confirmed in the nucleation assay, though the rate of nucleation was not inhibited but number of crystals was found to be decreased. The test drug also inhibited crystal aggregation. It can be concluded therefore, that the test drug possesses significant antilithiasic activity.

  18. Embeded photonic crystal at the interface of p-GaN and Ag reflector to improve light extraction of GaN-based flip-chip light-emitting diode

    Energy Technology Data Exchange (ETDEWEB)

    Zhen, Aigong; Ma, Ping, E-mail: maping@semi.ac.cn; Zhang, Yonghui; Guo, Enqing; Tian, Yingdong; Liu, Boting; Guo, Shikuan; Shan, Liang; Wang, Junxi; Li, Jinmin [Semiconductor Lighting R and D Center, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083 (China)

    2014-12-22

    In this experiment, a flip-chip light-emitting diode with photonic crystal was fabricated at the interface of p-GaN and Ag reflector via nanospheres lithography technique. In this structure, photonic crystal could couple with the guide-light efficiently by reason of the little distance between photonic crystal and active region. The light output power of light emitting diode with embedded photonic crystal was 1.42 times larger than that of planar flip-chip light-emitting diode. Moreover, the embedded photonic crystal structure makes the far-field divergence angle decreased by 18° without spectra shift. The three-dimensional finite difference time domain simulation results show that photonic crystal could improve the light extraction, and enhance the light absorption caused by Ag reflector simultaneously, because of the roughed surface. The depth of photonic crystal is the key parameter affecting the light extraction and absorption. Light extraction efficiency increases with the depth photonic crystal structure rapidly, and reaches the maximum at the depth 80 nm, beyond which light extraction decrease drastically.

  19. Synthesis of Analcime Crystals and Simultaneous Potassium Extraction from Natrolite Syenite

    Directory of Open Access Journals (Sweden)

    Jian Chen

    2017-01-01

    Full Text Available Analcime single crystals were successfully synthesized from natrolite syenite powder (K2O 10.89% and 92.6% of potassium was extracted simultaneously by means of soda roasting followed by alkali-hydrothermal method. Effects of NaOH concentration, reaction temperature, and holding period on the analcime formation and potassium extraction were investigated systemically. The results indicated that NaOH concentration plays an important role in determining the chemical composition of zeolites and size distribution; by turning the NaOH concentrations, three different pure zeolites (i.e., the phillipsite-Na, the analcime, and the sodalite were prepared. Besides, a higher temperature could accelerate the dissolution of K+ ions and enhance the crystallinity degree of zeolite. The reactions involved in the analcime synthesis can be summarized as follows: sodium aluminum silicate dissolution → precipitation and dissolution of metastable zeolite-P → analcime nucleation → analcime growth. The extraction ratio of K+ is associated with the types of synthesized zeolites, among which analcime is the most effective to promote potassium leaching out from zeolite lattice position. The optimal condition for analcime crystallization and K+ leaching is found to be as follows: 175°C for 4 h in 0.5 mol/L NaOH solution.

  20. The peculairities of material crystallization experiments in the CF-18 centrifuge under high gravity

    Science.gov (United States)

    Burdin, B. V.; Regel, L. L.; Turchaninov, A. M.; Shumaev, O. V.

    1992-04-01

    This paper presents data on the crystallization of various materials using the CF-18 centrifuge at the Gagarin Cosmonaut Center. The geometry and equipment are described. Consideration is given to some peculiarities of preparing and conducting crystal growth experiments in this centrifuge. Vibration in a coordinate system fixed to the crystal growth equipment and the reasons for its initiation are shown. From the results of experiments conducted during the last 10 years, it was concluded that there are many possibilities of using various classes of model materials to study crystal growth processes under high gravity conditions.

  1. Removal of crystal violet dye from aqueous solution using triton X-114 surfactant via cloud point extraction

    Directory of Open Access Journals (Sweden)

    Arunagiri Appusamy

    2014-09-01

    Full Text Available In this work, the cloud point extraction (CPE was carried out for the removal of crystal violet dye from aqueous solution using triton X-114 surfactant. Density, refractive index and viscosity of pure components and two different phases of the mixture were measured, and the corresponding excess molar volume was calculated. Most of the dye molecules get solubilized in the coacervate phase, leaving a dye free dilute phase. This experiment was conducted for different sets of surfactant and solute concentration in order to find out the cloud point temperature and their influencing factors such as extraction efficiency, phase volume ratio, distribution coefficient and pre-concentration factor. Furthermore, the thermodynamic parameters like change in Gibbs-free energy (ΔG0, the change in enthalpy (ΔH0 and the change in entropy (ΔS0 were analyzed and found that cloud point extraction with surfactant was a more feasible process in the removal of dyes from aqueous solution.

  2. Straw man 900-1000 GeV crystal extraction test beam for Fermilab collider operation

    Energy Technology Data Exchange (ETDEWEB)

    Carrigan, R.A. Jr.

    1996-10-01

    A design for a 900-1000 GeV, 100 khz parasitic test beam for use during collider operations has been developed. The beam makes use of two bent crystals, one for extraction and the other one for redirecting the beam in to the present Switchyard beam system. The beam requires only a few modifications in the A0 area and largely uses existing devices. It should be straight-forward to modify one or two beam lines in the fixed target experimental areas to work above 800 GeV. Possibilities for improvements to the design,to operate at higher fluxes are discussed.

  3. Light extraction enhancement of SOI-based erbium/oxygen Co-implanted photonic crystal microcavities

    Institute of Scientific and Technical Information of China (English)

    Zhang Jiashun; Wang Yue; Wu Yuanda; Zhang Xiaoguang; Jiang Ting; An Junming; Li Jianguang; Wang Hongjie; Hu Xiongwei

    2011-01-01

    H5 photonic crystal (PC) microcavities co-implanted with erbium (Er) and oxygen (O) ions were fabricated on silicon-on-insulator (SOI) wafers.Photoluminescence (PL) measurements were taken at room temperature and a light extraction enhancement of up to 12 was obtained at 1.54μm,as compared to an identically implanted unpatterned SOI wafer.In addition,we also explored the adjustment of cavity modes by changing the structural parameters of the PC,and the measured results showed that the cavity-resonant peaks shifted towards shorter wavelengths as the radius of the air holes increased,which is consistent with the theoretical simulation.

  4. Enhancing extraction efficiency of mid-infrared fluorescence in chalcogenide glass via photonic crystal

    Science.gov (United States)

    Zhang, Jun; Zhang, Peiqing; Ma, Beijiao; Dai, Shixun; Zhang, Wei; Nie, Qiuhua

    2016-04-01

    The use of rare earth-doped chalcogenide glass is an attractive method to develop mid-infrared sources. In this work, Er3+-doped chalcogenide glass is prepared, and photonic crystal (PC) pattern is designed to improve the extraction efficiency of light emission from the sample surface. The finite difference time domain simulation shows that the light extraction efficiency from the sample surface can be 1.62 times stronger than that from the sample without PC structure by introducing a simple two-dimensional (2D) PC structure into glass samples. This improvement was the result of the efficient light diffraction on the surface because of the integrated 2D PC. Results in this work offer a potential in developing midinfrared light sources.

  5. Extraction of distance restraints from pure shift NOE experiments

    Science.gov (United States)

    Kaltschnee, Lukas; Knoll, Kevin; Schmidts, Volker; Adams, Ralph W.; Nilsson, Mathias; Morris, Gareth A.; Thiele, Christina M.

    2016-10-01

    NMR techniques incorporating pure shift methods to improve signal resolution have recently attracted much attention, owing to their potential use in studies of increasingly complex molecular systems. Extraction of frequencies from these simplified spectra enables easier structure determination, but only a few of the methods presented provide structural parameters derived from signal integral measurements. In particular, for quantification of the nuclear Overhauser effect (NOE) it is highly desirable to utilize pure shift techniques where signal overlap normally prevents accurate signal integration, to enable measurement of a larger number of interatomic distances. However, robust methods for the measurement of interatomic distances using the recently developed pure shift techniques have not been reported to date. In this work we discuss some of the factors determining the accuracy of measurements of signal integrals in interferogram-based Zangger-Sterk (ZS) pure shift NMR experiments. The ZS broadband homodecoupling technique is used in different experiments designed for quantitative NOE determination from pure shift spectra. It is shown that the techniques studied can be used for quantitative extraction of NOE-derived distance restraints, as exemplified for the test case of strychnine.

  6. Young's double-slit experiment in photonic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Lei, E-mail: mywaters@iastate.edu [Ames Laboratory - U.S. DOE and Department of Physics and Astronomy, Iowa State University, Ames, IA 50011 (United States); Koschny, Thomas [Ames Laboratory - U.S. DOE and Department of Physics and Astronomy, Iowa State University, Ames, IA 50011 (United States); Soukoulis, C.M. [Ames Laboratory - U.S. DOE and Department of Physics and Astronomy, Iowa State University, Ames, IA 50011 (United States); Institute of Electronic Structure and Lasers (IESL), FORTH, 71110 Heraklion, Crete (Greece)

    2012-10-15

    We present an experimental and numerical study of the transmission of a photonic crystal perforated by two subwavelength slits, separated by two wavelengths. The experimental near-field image of the double-slit design of the photonic crystal shows an interference pattern, which is analogous to Young's experiment. This interference arises as a consequence of the excitation of surface states of the photonic crystals and agrees very well with the simulations.

  7. Young's double-slit experiment in photonic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Lei; Koschny, Thomas; Soukoulis, Costas M.

    2012-10-01

    We present an experimental and numerical study of the transmission of a photonic crystal perforated by two sub-wavelength slits, separated by two wavelengths.The experimental near-field image of the double-slit design of the photonic crystal shows an interference pattern, which is analogous to Young’s experiment. This interference arises as a consequence of the excitation of surface states of the photonic crystals and agrees very well with the simulations.

  8. Melt extraction in mush zones: The case of crystal-rich enclaves at the Sabatini Volcanic District (central Italy)

    Science.gov (United States)

    Masotta, M.; Mollo, S.; Gaeta, M.; Freda, C.

    2016-04-01

    A peculiar feature of the Sabatini Volcanic District (SVD, central Italy) is the occurrence of crystal-poor pumices and crystal-rich enclaves within the same eruptive host-deposit. The stratigraphic sequence of pumices and enclaves indicates the tapping of a stratified magma chamber, where a crystal-poor phonolitic magma lay on top of a more primitive crystal-rich magma. The crystal-rich enclaves are genetically related to the pumices and record the evolution of a solidification front, in which a more differentiated melt was produced, extracted and eventually erupted. We collected and analyzed crystal-rich enclaves from one of the largest phonolitic eruptions at the SVD and used their petrological and geochemical features to reconstruct magma differentiation and crystal-melt separation in the solidification front. On this basis, three groups of enclaves have been identified: porphyritic enclaves, holocrystalline enclaves and sanidinites. The mineralogical variability faithfully reproduces the spatial and temporal evolution expected of a solidification front, from early-to-intermediate crystallization conditions (porphyritic and holocrystalline type) to the late stage of solidification (sanidinites), in which the percolation of a more differentiated melt through the crystal mush triggered the instability of the solidification front. Results from numerical models indicate that gravitational instability is the most efficient mechanism to explain melt extraction in mush zones of medium-sized (~ 10 km3), short-lived (~ 104 years) magma chambers.

  9. Propagation optical quarks after an uniaxial crystal: the experiment

    Science.gov (United States)

    Egorov, Yu. A.; Konovalenko, V. L.; Zinovev, A. O.; Anischenko, P. M.; Glumova, M. V.

    2013-12-01

    There is a lots of different papers reporting about the propagation of the different types of an optical beams in a uniaxial crystals are known by that time. This beams are: Lager-Gaussian and Bessel- Gaussian beams. It is common for all this types of beams, that if propagation axis and crystal axis coincides, and accident beam had a circular polarization, are can get type spiral type degenerated umbilici, which corresponds to the charge 2 optical vortex in the orthogonal polarized beam component, generated by crystal [1] (Fig 1). This generation accurse due to total angular momentum conservation law symmetry axis of the crystal. One to the changing of the spin momentum which is associated with the beam polarization, this leads to the orbital momentum changes that associated with topological charge of formed orthogonal circular component. Double charged optical vortex could be easily perturbed by tilting beam axis with respect to the crystal axis. If the tilt angles are small (<0.1°) central umbilici splits on two lemons and the surrounding ring umbilici splits on two pairs of monster-star. The further increasing of the tilt angle leads to the topological charge of circular components becomes, equal, and additional orbital moment correspond to the beam mass center displacement.

  10. Ignition and growth modeling of detonation reaction zone experiments on single crystals of PETN and HMX

    Science.gov (United States)

    White, Bradley W.; Tarver, Craig M.

    2017-01-01

    It has long been known that detonating single crystals of solid explosives have much larger failure diameters than those of heterogeneous charges of the same explosive pressed or cast to 98 - 99% theoretical maximum density (TMD). In 1957, Holland et al. demonstrated that PETN single crystals have failure diameters of about 8 mm, whereas heterogeneous PETN charges have failure diameters of less than 0.5 mm. Recently, Fedorov et al. quantitatively determined nanosecond time resolved detonation reaction zone profiles of single crystals of PETN and HMX by measuring the interface particle velocity histories of the detonating crystals and LiF windows using a PDV system. The measured reaction zone time durations for PETN and HMX single crystal detonations were approximately 100 and 260 nanoseconds, respectively. These experiments provided the necessary data to develop Ignition and Growth (I&G) reactive flow model parameters for the single crystal detonation reaction zones. Using these parameters, the calculated unconfined failure diameter of a PETN single crystal was 7.5 +/- 0.5 mm, close to the 8 mm experimental value. The calculated failure diameter of an unconfined HMX single crystal was 15 +/- 1 mm. The unconfined failure diameter of an HMX single crystal has not yet been determined precisely, but Fedorov et al. detonated 14 mm diameter crystals confined by detonating a HMX-based plastic bonded explosive (PBX) without initially overdriving the HMX crystals.

  11. Determination of crystal violet in water by direct solid phase spectrophotometry after rotating disk sorptive extraction.

    Science.gov (United States)

    Manzo, Valentina; Navarro, Orielle; Honda, Luis; Sánchez, Karen; Inés Toral, M; Richter, Pablo

    2013-03-15

    The microextraction of crystal violet (CV) from water samples into polydimethylsiloxane (PDMS) using the rotating disk sorptive extraction (RDSE) technique was performed. The extracting device was a small Teflon disk that had an embedded miniature magnetic stirring bar and a PDMS (560 μL) film attached to one side of the disk using double-sided tape. The extraction involves a preconcentration of CV into the PDMS, where the analyte is then directly quantified using solid phase spectrophotometry at 600 nm. Different chemical and extraction device-related variables were studied to achieve the best sensitivity for the determination. The optimum extraction was performed at pH 14 because under this condition, CV is transformed to the neutral and colorless species carbinol, which can be quantitatively transferred to the PDMS phase. Although the colorless species is the chemical form extracted in the PDMS, an intense violet coloration appeared in the phase because the -OH bond in the carbinol molecule is weakened through the formation of hydrogen bonds with the oxygen atoms of the PDMS, allowing the resonance between the three benzene rings to compensate for the charge deficit on the central carbon atom of the molecule. The accuracy and precision of the method were evaluated in river water samples spiked with 10 and 30 μg L(-1) of CV, yielding a relative standard deviation of 6.2% and 8.4% and a recovery of 98.4% and 99.4%, respectively. The method detection limit was 1.8 μg L(-1) and the limit of quantification was 5.4 μg L(-1), which can be decreased if the sample volume is increased.

  12. Growth inhibition of struvite crystals in the presence of herbal extract Commiphora wightii.

    Science.gov (United States)

    Chauhan, C K; Joshi, M J; Vaidya, A D B

    2009-12-01

    Struvite is one of the components of urinary stone. Large number of people is suffering from urinary stones (calculi) problem all over the globe. These stones can grow rapidly forming "staghorn-calculi", which is more painful urological disorder. Therefore, it is of prime importance to study the growth and inhibition of Struvite crystals. This in vitro study has been carried out in the presence of herbal extract of Commiphora wightii by using single diffusion gel growth technique. Sodium metasilicate solution of specific gravity 1.05 and an aqueous solution of ammonium dihydrogen phosphate of 0.5 M concentration were mixed so that the pH value 7.0 could be set. After the gelation, equal amount of supernatant solutions comprising of pure 1.0 M magnesium acetate as well as the mixtures of magnesium acetate and the herbal extract solutions of 0.5 and 1% concentrations of C. wightii were gently poured on the set gels. From the study of growth and inhibition behavior of Struvite crystals, it was found that C. wightii inhibits the growth of the Struvite. This study incorporates multidisciplinary interests and may be used for formulating the strategy for prevention or dissolution of urinary stones.

  13. Sodium chloride precipitation reaction coefficient from crystallization experiment in a microfluidic device

    Science.gov (United States)

    Naillon, A.; Joseph, P.; Prat, M.

    2017-04-01

    The crystal growth of sodium chloride from an aqueous solution is studied from evaporation experiments in microfluidic channels in conjunction with analytical and numerical computations. The crystal growth kinetics is recorded using a high speed camera in order to determine the intrinsic precipitation reaction coefficient. The study reveals that the crystal growth rates determined in previous studies are all affected by the ions transport phenomena in the solution and thus not representative of the precipitation reaction. It is suggested that accurate estimate of sodium chloride precipitation reaction coefficient presented here offers new opportunities for a better understanding of important issues involved in the damages of porous materials induced by the salt crystallization.

  14. Ionization annealing of semiconductor crystals. Part two: the experiment

    Directory of Open Access Journals (Sweden)

    Garkavenko A. S.

    2014-12-01

    Full Text Available There is a conception that irradiation of semiconductor crystals with high energy electrons (300 keV results in a significant and irreversible deterioration of their electrical, optical and structural properties. Semiconductors are typically irradiated by low voltage electron accelerators with a continuous flow, the current density in such accelerators is 10–5—10–6 A/cm2, the energy — 0,3—1 MeV. All changes in the properties after such irradiation are resistant at room temperature, and marked properties recovery to baseline values is observed only after prolonged heating of the crystals to a high temperature. In contrast, the authors in their studies observe an improvement of the structural properties of semiconductor crystals (annealing of defects under irradiation with powerful (high current pulsed electron beams of high energy (E0 = 0,3–1 MeV, t = 0,1—10 ns, Ω = 1—10 Hz, j = 20—300 A/cm2. In their previous paper, the authors presented theoretical basis of this effect. This article describes an experimental study on the influence of high-current pulsed electron beams on the optical homogeneity of semiconductor GaAs and CdS crystals, confirming the theory put forward earlier.

  15. Experience with CsI(Na) crystals for calorimetry

    Energy Technology Data Exchange (ETDEWEB)

    Aulchenko, V.M. [Rossijskaya Akademiya Nauk, Novosibirsk (Russian Federation). Inst. Yadernoj Fiziki; Baibusinov, B.O. [Rossijskaya Akademiya Nauk, Novosibirsk (Russian Federation). Inst. Yadernoj Fiziki; Baldin, E.M. [Rossijskaya Akademiya Nauk, Novosibirsk (Russian Federation). Inst. Yadernoj Fiziki; Bondar, A.E. [Rossijskaya Akademiya Nauk, Novosibirsk (Russian Federation). Inst. Yadernoj Fiziki; Gaidarev, P.B. [Cornell Univ., Ithaca, NY (United States); Kuzmin, A.S. [Rossijskaya Akademiya Nauk, Novosibirsk (Russian Federation). Inst. Yadernoj Fiziki; Leontiev, L.A. [Rossijskaya Akademiya Nauk, Novosibirsk (Russian Federation). Inst. Yadernoj Fiziki; Oreshkin, S.B. [Rossijskaya Akademiya Nauk, Novosibirsk (Russian Federation). Inst. Yadernoj Fiziki; Ovechkin, R.P. [Rossijskaya Akademiya Nauk, Novosibirsk (Russian Federation). Inst. Yadernoj Fiziki; Shwartz, B.A. [Rossijskaya Akademiya Nauk, Novosibirsk (Russian Federation). Inst. Yadernoj Fiziki

    1996-09-21

    The performance of cesium iodide doped with sodium is studied. The design and parameters of a CsI(Na) endcap calorimeter for the KEDR detector are presented. Also reported are the results of the study of a calorimeter element consisting of a CsI(Na) crystal coupled to a vacuum phototriode. (orig.).

  16. The Quartz-Crystal Microbalance in an Undergraduate Laboratory Experiment: I. Fundamentals and Instrumentation

    Science.gov (United States)

    Tsionsky, Vladimir

    2007-01-01

    The fundamentals, as well as the instrumentation of the quartz-crystal microbalance (QCM) technique that is used in an undergraduate laboratory experiment are being described. The QCM response can be easily used to change the properties of any system.

  17. Experiments testing the abatement of radiation damage in D-xylose isomerase crystals with cryogenic helium.

    Science.gov (United States)

    Hanson, B Leif; Harp, Joel M; Kirschbaum, Kristin; Schall, Constance A; DeWitt, Ken; Howard, Andrew; Pinkerton, A Alan; Bunick, Gerard J

    2002-11-01

    Helium is a more efficient cryogen than nitrogen, and for macromolecular data collection at high-flux beamlines will deliver lower temperatures. An open-flow helium cryostat developed at the University of Toledo (the Pinkerton Device) has been used for macromolecular data collection. This device differs from standard commercial He cryostats by having a much narrower aperture providing a high velocity stream of He around the crystal that maximizes convective and conductive heat exchange between the crystal and the cryogen. This paper details a series of experiments conducted at the IMCA-CAT 17ID beamline using one crystal for each experimental condition to examine whether helium at 16 K provided better radiation-damage abatement compared with nitrogen at 100 K. These studies used matched high-quality crystals (0.94 A diffraction resolution) of D-xylose isomerase derived from the commercial material Gensweet SGI. Comparisons show that helium indeed abates the indicators of radiation damage, in this case resulting in longer crystal diffractive lifetimes. The overall trend suggests that crystals maintain order and that high-resolution data are less affected by increased radiation load when crystals are cooled with He rather than N(2). This is probably the result of a lower effective temperature at the crystal with concomitant reduction in free-radical diffusion. Other features, such as an apparent phase transition in macromolecular crystals at lower temperatures, require investigation to broaden the utility of He use.

  18. Light extraction of GaN LEDs with 2-D photonic crystal structure

    Institute of Scientific and Technical Information of China (English)

    Hongwei Liu; Qiang Kan; Chunxia Wang; Feng Yu; Xingsheng Xu; Hongda Chen

    2009-01-01

    Ultraviolet photo-lithography is employed to introduce two-dimensional (2D) photonic crystal (PC) structure on the top surface of GaN-based light emitting diode (LED).PC patterns are transferred to 460-nmthick transparent indium tin oxide (ITO) electrode by inductively coupled plasma (ICP) etching.Light intensity of PC-LED can be enhanced by 38% comparing with the one without PC structure.Rigorous coupled wave analysis method is performed to calculate the light transmission spectrum of PC slab.Simulation results indicate that total internal reflect angle which modulated by PC structure has been increased by 7°,which means that the light extraction efficiency is enhanced outstandingly.

  19. The Determination of Vanillin Extract: An Analytical Undergraduate Experiment

    Science.gov (United States)

    Beckers, Jozef L.

    2005-01-01

    The student results are presented for the determination of vanillin in a vanilla extract as part of a problem-solving approach. The determination of the vanillin concentration in the Dutch product "Baukje vanilla extract" is described.

  20. The Ice Selective Inlet: a novel technique for exclusive extraction of pristine ice crystals in mixed-phase clouds

    Directory of Open Access Journals (Sweden)

    P. Kupiszewski

    2014-12-01

    Full Text Available Climate predictions are affected by high uncertainties partially due to an insufficient knowledge of aerosol-cloud interactions. One of the poorly understood processes is formation of mixed-phase clouds (MPCs via heterogeneous ice nucleation. Field measurements of the atmospheric ice phase in MPCs are challenging due to the presence of supercooled liquid droplets. The Ice Selective Inlet (ISI, presented in this paper, is a novel inlet designed to selectively sample pristine ice crystals in mixed-phase clouds and extract the ice residual particles contained within the crystals for physical and chemical characterisation. Using a modular setup composed of a cyclone impactor, droplet evaporation unit and pumped counterflow virtual impactor (PCVI, the ISI segregates particles based on their inertia and phase, exclusively extracting small ice particles between 5 and 20 μm in diameter. The setup also includes optical particle spectrometers for analysis of the number size distribution and shape of the sampled hydrometeors. The novelty of the ISI is a droplet evaporation unit, which separates liquid droplets and ice crystals in the airborne state, thus avoiding physical impaction of the hydrometeors and limiting potential artifacts. The design and validation of the droplet evaporation unit is based on modelling studies of droplet evaporation rates and computational fluid dynamics simulations of gas and particle flows through the unit. Prior to deployment in the field, an inter-comparison of the WELAS optical particle size spectrometers and a characterisation of the transmission efficiency of the PCVI was conducted in the laboratory. The ISI was subsequently deployed during the Cloud and Aerosol Characterisation Experiment (CLACE 2013 – an extensive international field campaign encompassing comprehensive measurements of cloud microphysics, as well as bulk aerosol, ice residual and ice nuclei properties. The campaign provided an important opportunity

  1. The Ice Selective Inlet: a novel technique for exclusive extraction of pristine ice crystals in mixed-phase clouds

    Science.gov (United States)

    Kupiszewski, P.; Weingartner, E.; Vochezer, P.; Schnaiter, M.; Bigi, A.; Gysel, M.; Rosati, B.; Toprak, E.; Mertes, S.; Baltensperger, U.

    2015-08-01

    Climate predictions are affected by high uncertainties partially due to an insufficient knowledge of aerosol-cloud interactions. One of the poorly understood processes is formation of mixed-phase clouds (MPCs) via heterogeneous ice nucleation. Field measurements of the atmospheric ice phase in MPCs are challenging due to the presence of much more numerous liquid droplets. The Ice Selective Inlet (ISI), presented in this paper, is a novel inlet designed to selectively sample pristine ice crystals in mixed-phase clouds and extract the ice residual particles contained within the crystals for physical and chemical characterization. Using a modular setup composed of a cyclone impactor, droplet evaporation unit and pumped counterflow virtual impactor (PCVI), the ISI segregates particles based on their inertia and phase, exclusively extracting small ice particles between 5 and 20 μm in diameter. The setup also includes optical particle spectrometers for analysis of the number size distribution and shape of the sampled hydrometeors. The novelty of the ISI is a droplet evaporation unit, which separates liquid droplets and ice crystals in the airborne state, thus avoiding physical impaction of the hydrometeors and limiting potential artefacts. The design and validation of the droplet evaporation unit is based on modelling studies of droplet evaporation rates and computational fluid dynamics simulations of gas and particle flows through the unit. Prior to deployment in the field, an inter-comparison of the optical particle size spectrometers and a characterization of the transmission efficiency of the PCVI was conducted in the laboratory. The ISI was subsequently deployed during the Cloud and Aerosol Characterization Experiment (CLACE) 2013 and 2014 - two extensive international field campaigns encompassing comprehensive measurements of cloud microphysics, as well as bulk aerosol, ice residual and ice nuclei properties. The campaigns provided an important opportunity for a

  2. The Ice Selective Inlet: a novel technique for exclusive extraction of pristine ice crystals in mixed-phase clouds

    Directory of Open Access Journals (Sweden)

    P. Kupiszewski

    2015-08-01

    Full Text Available Climate predictions are affected by high uncertainties partially due to an insufficient knowledge of aerosol–cloud interactions. One of the poorly understood processes is formation of mixed-phase clouds (MPCs via heterogeneous ice nucleation. Field measurements of the atmospheric ice phase in MPCs are challenging due to the presence of much more numerous liquid droplets. The Ice Selective Inlet (ISI, presented in this paper, is a novel inlet designed to selectively sample pristine ice crystals in mixed-phase clouds and extract the ice residual particles contained within the crystals for physical and chemical characterization. Using a modular setup composed of a cyclone impactor, droplet evaporation unit and pumped counterflow virtual impactor (PCVI, the ISI segregates particles based on their inertia and phase, exclusively extracting small ice particles between 5 and 20 μm in diameter. The setup also includes optical particle spectrometers for analysis of the number size distribution and shape of the sampled hydrometeors. The novelty of the ISI is a droplet evaporation unit, which separates liquid droplets and ice crystals in the airborne state, thus avoiding physical impaction of the hydrometeors and limiting potential artefacts. The design and validation of the droplet evaporation unit is based on modelling studies of droplet evaporation rates and computational fluid dynamics simulations of gas and particle flows through the unit. Prior to deployment in the field, an inter-comparison of the optical particle size spectrometers and a characterization of the transmission efficiency of the PCVI was conducted in the laboratory. The ISI was subsequently deployed during the Cloud and Aerosol Characterization Experiment (CLACE 2013 and 2014 – two extensive international field campaigns encompassing comprehensive measurements of cloud microphysics, as well as bulk aerosol, ice residual and ice nuclei properties. The campaigns provided an important

  3. On Slip Transmission Criteria in Experiments and Crystal Plasticity Models

    CERN Document Server

    Bayerschen, E; Reddy, B D; Böhlke, T

    2015-01-01

    A comprehensive overview is given on the slip transmission criteria for grain boundaries in the experimental literature, with a focus on slip system and grain boundary orientation. The use of these geometric criteria in continuum crystal plasticity models is briefly discussed. Perspectives on additional experimentally motivated criteria used in computational simulations are given. The theoretical framework of Gurtin (2008, J. Mech. Phys. Solids 56, p. 640) is reviewed for the single slip case with the aim of showing explicitly the connections to the experimentally developed criteria for slip transmission that are not discussed in the work itself.

  4. Spectral-distortion-free light extraction from organic light-emitting diodes using nanoscale photonic crystal

    Science.gov (United States)

    Shim, Yong Sub; Nyun Kim, Kyu; Hwang, Ju Hyun; Hwee Park, Cheol; Jung, Sun-Gyu; Park, Young Wook; Ju, Byeong-Kwon

    2017-01-01

    Despite their generally good performance, photonic crystal (PC)-based organic light-emitting diodes (OLEDs) encounter a serious spectral distortion problem. In this study, we obtained spectral-distortion-free PC-based OLEDs by lowering the pitch (period of the PC) to less than a half the emission wavelength, using a simple and scalable nanoscale process of laser interference lithography. The demonstrated OLEDs with 200 nm pitch-size nanoscale periodic hole arrays exhibited negligible changes in the Internal Commission on Illumination 1931 color coordinate of Δ (0.0104, 0.0078) and a peak wavelength of Δ0 nm (relative to the reference), while maintaining the function of the internal light extraction layer, manifested as a 23% enhancement of the external quantum efficiency (EQE). The enhancement of the EQE reached 85% after incorporating a micro-lens array. The improved light extraction, spectral-distortion-free characteristic, and excellent color stability over a broad range of viewing angles were successfully derived by performing finite difference time domain simulations.

  5. New results from the CERN-SPS beam deflection experiments with bent crystals

    Science.gov (United States)

    Baurichter, A.; Kirsebom, K.; Medenwaldt, R.; Møller, S. P.; Worm, T.; Uggerhøj, E.; Mikkelsen, U.; Graftström, P.; Gatignon, L.; Elsener, K.; Doble, N.; Biino, C.; Freund, A.; Vilakazi, Z.; Hage-Ali, M.; Siffert, P.; Clément, M.

    1996-10-01

    Results from five distinct bending experiments performed recently in the H8 beam at CERN are presented. Firstly, deflection of a positive pion beam at 200 GeV/c is compared to the "standard" 450-GeV/c proton beam for a bending angle of 3.1 mrad along the (111) plane in a 50 mm silicon crystal. Second, deflection of negative pions at 200 GeV/c is investigated for the same crystal, for incidence along the (111) plane as well as the axis. Small deflection effects are seen, but no negative particles are bent through the full bending angle of the crystal. Third, the first results from beam deflection at high energy using a germanium crystal are shown. Slightly higher deflection efficiencies than for silicon are seen for large bending angles, but significantly smaller than expected for such a crystal with higher atomic number. Fourth, deflection efficiencies using a strongly irradiated silicon crystal have been measured for the first time, and a small reduction in efficiency is seen in the irradiated region. Finally, deflection of positive particles using axial alignment of a bent silicon crystal has been investigated at 450 GeV/c. Qualitatively similar behaviour as in previous experiments at 12 GeV/c is seen; the beam splits into several beams corresponding to the different planes, and even weak planes are observed.

  6. Extracting Strength from Ramp-Release Experiments on Z

    Science.gov (United States)

    Brown, Justin

    2013-06-01

    Releasing from a compressed state has long been recognized as a sensitive measure of a material's constitutive response. The initial elastic unloading provides insights which can be related to changes in shear stress or, in the context of classic plasticity, to the material's yield surface. Ramp compression and subsequent release experiments on Sandia's Z machine typically consist of a driving aluminum electrode pushing a sample material which is backed by a window. A particle velocity measurement of the sample/window interface provides a ramp-release profile. Under most circumstances, however, the impedance mismatch at this interface results in the measurement of a highly perturbed velocity, particularly at the late times of interest. Wave attenuation, the finite pressure range over which the material elastically unloads, and rate effects additionally complicate the interpretation of the experiment. In an effort to accurately analyze experiments of this type, each of these complications is addressed. The wave interactions are accounted for through the so-called transfer function methodology and involves a coupling of the experimental measurements with numerical simulations. Simulated window velocity measurements are combined with the corresponding in situ simulations to define a mapping describing the wave interactions due to the presence of the window. Applying this mapping to the experimentally measured velocity results in an in situ sample response which may then be used in a classic Lagrangian analysis from which the strength can be extracted via the self-consistent method. Corrections for attenuation, pressure averaging, and limitations of the analysis due to rate-effects are verified through the use of synthetic data. To date, results on the strength of aluminum to 1.2 MBar, beryllium to 1 MBar, and tantalum to over 2 MBar have been obtained through this methodology and will be presented. Sandia National Laboratories is a multi-program laboratory operated by

  7. Enhanced light extraction efficiency of plastic scintillator by photonic crystal prepared with a self-assembly method

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jinliang [State Key Laboratory of Intense Pulsed Radiation Simulation and Effect, Radiation Detection Research Center, Northwest Institute of Nuclear Technology, Xi’an, 710024 (China); Zhu, Zhichao [Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology, School of Physics Science and Engineering, Tongji University, Shanghai 200092 (China); Chen, Liang; Ouyang, Xiaoping [State Key Laboratory of Intense Pulsed Radiation Simulation and Effect, Radiation Detection Research Center, Northwest Institute of Nuclear Technology, Xi’an, 710024 (China); Liu, Bo, E-mail: lbo@tongji.edu.cn [Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology, School of Physics Science and Engineering, Tongji University, Shanghai 200092 (China); Cheng, Chuanwei [Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology, School of Physics Science and Engineering, Tongji University, Shanghai 200092 (China); Hu, Jing; He, Shiyi [State Key Laboratory of Intense Pulsed Radiation Simulation and Effect, Radiation Detection Research Center, Northwest Institute of Nuclear Technology, Xi’an, 710024 (China); Wang, Zewei [State Key Laboratory of Intense Pulsed Radiation Simulation and Effect, Radiation Detection Research Center, Northwest Institute of Nuclear Technology, Xi’an, 710024 (China); College of Materials Science and Engineering, Xiangtan University, Xiangtan 411105 (China); Gu, Mu; Chen, Hong [Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology, School of Physics Science and Engineering, Tongji University, Shanghai 200092 (China)

    2015-09-21

    Plastic scintillators are extensively used in various radiation measurement systems. However the total internal reflection decreases the scintillation light output, leading to a low detection efficiency especially in these weak signal detection situations. In the present investigation, we have designed a light extraction scheme based on the photonic crystal formed with a monolayer periodic array of polystyrene nanospheres by a self-assembly method. The photonic crystal coated on the surface of plastic scintillator can significantly enhance the light extraction by 120% compared with the plain reference sample under X-ray excitation, which is achieved by the principle of the coupling of evanescent field near the scintillator-air interface with the photonic crystal.

  8. Characterization of PbWO4 crystals for high-energy physics experiments

    Science.gov (United States)

    Kim, M. J.; Park, H.; Kim, H. J.

    2016-09-01

    High-energy physics (HEP) experiments have employed many new types of scintillators. Specifically, bismuth germanate, thallium-doped cesium iodide, and lead tungstate (PbWO4, PWO) have been used for the L3 experiment; CLEO II, Belle and BES-III; and CMS, respectively. PWO has particularly beneficial properties, such as high density, fast decay time, short radiation length and radiation hardness. In this study, we tested the PWO crystals at low temperatures to determine their applicability in future calorimeters. Various crystals from the Proton Antiproton Annihilations at Darmstadt (PANDA) experiment in Giessen, the Bogoroditsk Techno-Chemical Plant (BTCP) in Russia and by Shanghai Institute of Ceramics, Chinese Academy of Sciences (SICCAS) in China were investigated. We studied the scintillation properties of PWO crystals, such as their X-ray luminescence, relative light yields, absolute light yields, energy resolutions, decay times and longitudinal uniformities of their light yields. In addition, we measured the temperature dependences of the light yields and decay times by using a 137Cs γ-ray source. The emission spectra of the PWO crystals consisted of a broad band from 350 nm to 700 nm, and the peak emission wavelength in each spectrum was 420 nm. The emission spectra of the PWO crystals from SICCAS were slightly shifted to longer wavelengths compared with those of the crystals from the other institutions.

  9. Multidisciplinary approach to transvenous lead extraction: a single center's experience.

    Science.gov (United States)

    Maus, Timothy M; Shurter, Jesse; Nguyen, Liem; Birgersdotter-Green, Ulrika; Pretorius, Victor

    2015-04-01

    To evaluate the success and complication rates of a single center's multidisciplinary approach to transvenous lead extraction. One university hospital. One hundred ninety-five patients scheduled for transvenous lead extraction. A multidisciplinary approach to transvenous lead extraction involving cardiac surgery, electrophysiology, perfusion, and cardiac anesthesiology. A case series of 351 lead extractions performed in 195 patients over a 42-month period. Indications, success rates, and complication rates were tracked and retrospectively evaluated and reported. Indications for lead extraction included 53.3% because of lead malfunction, 36.9% because of infection, with the remaining 9.7% from other categories such as venous stenosis. The lead extraction rate was 99.7%, with complete removal in 97.7%. The overall major complication rate was 3.08%. After an initial 1-year period of performing lead extractions, the overall major complication rate reduced to 1.23%. Transvenous lead extraction generally is a safe procedure, but not without complications. A multidisciplinary approach involving cardiac surgery, electrophysiology, and cardiac anesthesiology allows for successful management and the ability to rapidly manage major complications. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. New states as observed by the Crystal Barrel experiment

    Energy Technology Data Exchange (ETDEWEB)

    Augustin, I.; Amsler, C.; Baker, C.A.; Barnett, B.M.; Batty, C.J.; Beuchert, K.; Birien, P.; Bistirlich, J.; Bluem, P.; Bossingham, R.; Bossy, H.; Braune, K.; Brose, J.; Bugg, D.V.; Burchell, M.; Case, T.; Chung, S.U.; Cooper, A.; Crowe, K.M.; Dietz, H.P.; Dombrowski, S. v.; Doser, M.; Duennweber, W.; Engelhardt, D.; Englert, M.; Faessler, M.A.; Felix, C.; Folger, G.; Hackmann, R.; Haddock, R.P.; Heinsius, F.H.; Hessey, N.P.; Hidas, P.; Illinger, P.; Jamnik, D.; Javorfi, Z.; Kalinowsky, H.; Kaemmle, B.; Kiel, T.; Kisiel, J.; Klempt, E.; Kobel, M.; Koch, H.; Kolo, C.; Koenigsmann, K.; Kunze, M.; Landua, R.; Luedemann, J.; Matthaey, H.; Merkel, M.; Merlo, J.P.; Meyer, C.A.; Meyer-Berkhout, U.; Montanet, L.; Noble, A.; Peters, K.; Pinter, G.; Ravndal, S.; Sanjari, A.H.; Schaefer, E.; Schmid, B.; Schmidt, P.; Spanier, S.; Strassburger, C.; Strohbusch, U.; Suffert, M.; Urner, D.; Voelcker, C.; Walter, F.; Walther, D.; Wiedner, U.; Winter, N.; Zoll, J.; Zupancic, C. (Karlsruhe Univ. (Germany; Crystal Barrel Collaboration

    1993-06-07

    The Crystal Barrel Detector has been in operation since October 1989. Results on the analysis of the annihilation of protonium at rest into three pseudoscalars is presented. The [pi][sup 0][pi][sup 0][pi][sup 0] final state confirms the existence of f[sub 2](1520)[yields][pi][sup 0][pi][sup 0]. In the [eta][eta] system of the [pi][sup 0][eta][eta] final state an isoscalar J[sup PC]=0[sup ++] resonance with a mass of 1560 MeV/c[sup 2] and a width of 245 MeV/c[sup 2] is observed. The identification with f[sub 0](1590) is doubtful since the [eta][eta]' decay is not observed with the corresponding strength. Our analysis yields an upper limit for the relative branching ratio BR(f[sub 0](1560)[yields][eta][eta]')/(f[sub 0](1560)[yields][eta][eta])<0.24. (orig.)

  11. Smectic and columnar liquid crystals concepts and physical properties illustrated by experiments

    CERN Document Server

    Oswald, Patrick

    2005-01-01

    Liquid crystals allow us to perform experiments that provide insight into fundamental problems of modern physics, such as phase transitions, frustration, elasticity, hydrodynamics, defects, growth phenomena, and optics. Smectic and Columnar Liquid Crystals: Concepts and Physical Properties Illustrated by Experiments is a result of personal research and of the graduate lectures given by the authors at the École Normale Supérieure de Lyon and the University of Paris VII, respectively. The book examines lamellar (smectic) and columnar liquid crystals, which, in addition to orientational order, possess 1D, 2D or 3D positional order. This volume illustrates original physical concepts using methodically numerous experiments, theoretical developments, and diagrams. Topics include rheology and plasticity, ferroelectricity, analogies with superconductors, hexatic order and 2D-melting, equilibrium shapes, facetting, and the Mullins-Sekerka instability, as well as phase transitions in free films and membrane vibration...

  12. Liquid-Liquid Extraction of Insecticides from Juice: An Analytical Chemistry Laboratory Experiment

    Science.gov (United States)

    Radford, Samantha A.; Hunter, Ronald E., Jr.; Barr, Dana Boyd; Ryan, P. Barry

    2013-01-01

    A laboratory experiment was developed to target analytical chemistry students and to teach them about insecticides in food, sample extraction, and cleanup. Micro concentrations (sub-microgram/mL levels) of 12 insecticides spiked into apple juice samples are extracted using liquid-liquid extraction and cleaned up using either a primary-secondary…

  13. Liquid-Liquid Extraction of Insecticides from Juice: An Analytical Chemistry Laboratory Experiment

    Science.gov (United States)

    Radford, Samantha A.; Hunter, Ronald E., Jr.; Barr, Dana Boyd; Ryan, P. Barry

    2013-01-01

    A laboratory experiment was developed to target analytical chemistry students and to teach them about insecticides in food, sample extraction, and cleanup. Micro concentrations (sub-microgram/mL levels) of 12 insecticides spiked into apple juice samples are extracted using liquid-liquid extraction and cleaned up using either a primary-secondary…

  14. Lessons from high-throughput protein crystallization screening: 10 years of practical experience

    Science.gov (United States)

    JR, Luft; EH, Snell; GT, DeTitta

    2011-01-01

    Introduction X-ray crystallography provides the majority of our structural biological knowledge at a molecular level and in terms of pharmaceutical design is a valuable tool to accelerate discovery. It is the premier technique in the field, but its usefulness is significantly limited by the need to grow well-diffracting crystals. It is for this reason that high-throughput crystallization has become a key technology that has matured over the past 10 years through the field of structural genomics. Areas covered The authors describe their experiences in high-throughput crystallization screening in the context of structural genomics and the general biomedical community. They focus on the lessons learnt from the operation of a high-throughput crystallization screening laboratory, which to date has screened over 12,500 biological macromolecules. They also describe the approaches taken to maximize the success while minimizing the effort. Through this, the authors hope that the reader will gain an insight into the efficient design of a laboratory and protocols to accomplish high-throughput crystallization on a single-, multiuser-laboratory or industrial scale. Expert Opinion High-throughput crystallization screening is readily available but, despite the power of the crystallographic technique, getting crystals is still not a solved problem. High-throughput approaches can help when used skillfully; however, they still require human input in the detailed analysis and interpretation of results to be more successful. PMID:22646073

  15. Perspectives for nEDM Search by Crystal Diffraction. Test Experiment and Results

    Energy Technology Data Exchange (ETDEWEB)

    Fedorov, V.V. [Petersburg Nuclear Physics Institute, Gatchina, St. Petersburg (Russian Federation); Jentschel, M. [Institute Laue-Langevin, Grenoble (France); Kuznetsov, I.A.; Lapin, E.G. [Petersburg Nuclear Physics Institute, Gatchina, St. Petersburg (Russian Federation); Lelievre-Berna, E.; Nesvizhevsky, V.; Petoukhov, A. [Institute Laue-Langevin, Grenoble (France); Semenikhin, S.Yu. [Petersburg Nuclear Physics Institute, Gatchina, St. Petersburg (Russian Federation); Soldner, T. [Institute Laue-Langevin, Grenoble (France); Voronin, V.V. [Petersburg Nuclear Physics Institute, Gatchina, St. Petersburg (Russian Federation)], E-mail: vvv@pnpi.spb.ru; Braginetz, Yu.P. [Petersburg Nuclear Physics Institute, Gatchina, St. Petersburg (Russian Federation)

    2009-08-15

    An experiment searching for the neutron electric dipole moment by measuring spin-rotations in a non-centrosymmetric crystal was carried out to investigate the statistical sensitivity and systematic effects of the method. The preliminary result of this experiment is d{sub n}=(2.5{+-}6.5).10{sup -24} e.cm. The performance was essentially limited by the low luminosity of the prototype setup. With a dedicated setup and a large quartz crystal, the expected accuracy is {approx}2.10{sup -26} e.cm for 100 days of data collection.

  16. Inverse-problem approach to designing photonic crystals for cavity QED experiments.

    Science.gov (United States)

    Geremia, J M; Williams, Jon; Mabuchi, Hideo

    2002-12-01

    Photonic band gap (PBG) materials are attractive for cavity QED experiments because they provide extremely small mode volumes and are monolithic, integratable structures. As such, PBG cavities are a promising alternative to Fabry-Perot resonators. However, the cavity requirements imposed by QED experiments, such as the need for high Q (low cavity damping) and small mode volumes, present significant design challenges for photonic band gap materials. Here, we pose the PBG design problem as a mathematical inversion and provide an analytical solution for a two-dimensional (2D) crystal. We then address a planar (2D crystal with finite thickness) structure using numerical techniques.

  17. Molecularly Imprinted Polymers for Selective Extraction of Crystal Violet from Natural Seawater coupled with High- Performance Liquid Chromatographic Determination

    Institute of Scientific and Technical Information of China (English)

    LIAN Ziru; WANG Jiangtao

    2014-01-01

    Molecularly imprinted polymers (MIPs) were prepared by the bulk polymerization using crystal violet as the template molecule, and the methacrylic acid and ethylene glycol dimetheacrylate as functional monomer and cross-linker, respectively. Sys-tematic investigations of synthetic conditions were conducted. The surface morphology and recognition mechanism of the obtained polymers were studied using scanning electron microscope and spectrophotometric analysis. MIPs showed high affinity to template molecule and were successfully applied as special solid-phase extraction sorbent for selective extraction of crystal violet from natural seawater. An off-line molecularly imprinted solid-phase extraction (MISPE) method followed by high-performance liquid chroma-tography with diodearray detection for the analysis of crystal violet was also established. MISPE columns have good recoveries for crystal violet standard solutions and good linearity was obtained over the concentration range of 0-200μg L-1 (R2>0.99). Finally, two natural seawater samples were investigated. The recoveries of spiked seawater on the MISPE columns were from 44.47% to 62.34%, the relative standard deviation (n=3) being in the range of 2.89%-5.96%.

  18. Herbal extracts of Tribulus terrestris and Bergenia ligulata inhibit growth of calcium oxalate monohydrate crystals in vitro

    Science.gov (United States)

    Joshi, V. S.; Parekh, B. B.; Joshi, M. J.; Vaidya, A. B.

    2005-02-01

    A large number of people in this world are suffering from urinary stone problem. Calcium oxalate monohydrate (COM) and calcium oxalate dihydrate (COD) containing stones (calculi) are commonly found. In the present study, COM crystals were grown by a double diffusion gel growth technique using U-tubes. The gel was prepared from hydrated sodium metasilicate solution. The gel framework acts like a three-dimensional crucible in which the crystal nuclei are delicately held in the position of their formation, and nutrients are supplied for the growth. This technique can be utilized as a simplified screening static model to study the growth, inhibition and dissolution of urinary stones in vitro. The action of putative litholytic medicinal plants, Tribulus terrestris Linn. ( T.t) and Bergenia ligulata Linn. ( B.l.), has been studied in the growth of COM crystals. Tribulus terrestris and Bergenia ligulata are commonly used as herbal medicines for urinary calculi in India. To verify the inhibitive effect, aqueous extracts of Tribulus terrestris and Bergenia ligulata were added along with the supernatant solutions. The growth was measured and compared, with and without the aqueous extracts. Inhibition of COM crystal growth was observed in the herbal extracts. Maximum inhibition was observed in Bergenia ligulata followed by Tribulus terrestris. The results are discussed.

  19. The Quartz-Crystal Microbalance in an Undergraduate Laboratory Experiment: Measuring Mass

    Science.gov (United States)

    Tsionsky, Vladimir

    2007-01-01

    The study explains the quartz-crystal microbalance (QCM) technique, which is often used as an undergraduate laboratory experiment for measuring the mass of a system. QCM can be used as a mass sensor only when the measured mass is rigidly attached to the surface.

  20. The Quartz-Crystal Microbalance in an Undergraduate Laboratory Experiment II: Measuring Viscosity

    Science.gov (United States)

    Tsionsky, Vladimir

    2007-01-01

    Various water-alcohol and alcohol-alcohol based experiments are used to demonstrate how the quartz-crystal microbalance (QCM) technique is used for measuring the viscosity of a system. The technique is very advantageous, as it is inexpensive and provides digital output.

  1. Advantages of ice crystal growth experiments in a low gravity environment

    Science.gov (United States)

    Anderson, B. J.; Keller, V. W.; Hallett, J.

    1979-01-01

    The effects of convective fluid motions and mechanical supports on ice crystal growth in experiments conducted on earth can be inferred from studies conducted in their absence in a low-gravity environment. Current experimental results indicate the effects may be significant.

  2. Urinary stone formation: Efficacy of seed extract of Ensete superbum (Roxb.) Cheesman on growth inhibition of calcium hydrogen phosphate dihydrate crystals

    Science.gov (United States)

    Diana, K. J.; George, K. V.

    2013-01-01

    The effect of aqueous seed extract of Ensete superbum (Roxb.) Cheesman on in vitro crystallization and growth patterns of calcium hydrogen phosphate dihydrate (CaHPO4·2H2O, CHPD) crystals was studied using single diffusion gel growth technique. Reduction in growth of CHPD crystals was noticed with increasing concentrations of seed extract. The morphology of CHPD or brushite crystals was studied by microscopy. The structural changes of the treated crystals were assessed by SEM, FT-IR, XRD and TGA/DTA analysis. It is expected that this multidisciplinary approach for in vitro crystallization and characterization of CHPD crystals will provide a better explanation to develop novel strategies for prevention of urinary stones.

  3. Investigation of regime of intensive extraction of proton beam by curved crystal during simultaneous operation with internal targets on IHEP-U-70 accelerator

    CERN Document Server

    Afonin, A G; Galjaev, A N; Gres, V N; Grishina, S Y; Zapolskii, V N; Zelenov, B A; Kotov, V I; Maisheev, V A; Medvedev, V A; Minchenko, A V; Terekhov, V I; Troyanov, E F; Fedotov, Y S; Chesnokov, Yu A

    2002-01-01

    On describes a technique to extract proton beam from the IHEP U-70 synchrotron using a silicon curved crystal at simultaneous operation of several internal targets. The optimal range of crystal angles of curvature constitutes 0.5-2.5 mrad, beam length - 2-5 mm. The intensity range of the extracted beam may vary depending on the requirements imposed by physical experimental facilities ranging from 10 sup 7 up to 6.0 x 10 sup 1 sup 1 protons per U-70 operation cycle. The elaborated technique to extract accelerated beam by short crystals extends essentially possibilities to conduct physical researches using an accelerator

  4. Two-Stage Separation of V(IV) and Al(III) by Crystallization and Solvent Extraction from Aluminum-Rich Sulfuric Acid Leaching Solution of Stone Coal

    Science.gov (United States)

    Shi, Qihua; Zhang, Yimin; Liu, Tao; Huang, Jing; Liu, Hong

    2016-12-01

    To improve separation of V(IV) and Al(III) from aluminum-rich sulfuric acid leaching solution of stone coal, the two-stage separation by crystallization and solvent extraction methods have been developed. A co-extraction coefficient (k) was put forward to evaluate comprehensively co-extraction extent in different solutions. In the crystallization stage, 68.2% of aluminum can be removed from the solution. In the solvent extraction stage, vanadium was selectively extracted using di-2-ethylhexyl phosphoric acid/tri-n-butyl phosphate from the crystalline mother solution, followed by H2SO4 stripped efficiently. A V2O5 product with purity of 98.39% and only 0.10% Al was obtained after oxidation, precipitation, and calcination. Compared with vanadium extraction from solution without crystallization, the counter-current extraction stage of vanadium can be decreased from 6 to 3 and co-extraction coefficient (k) decreased from 2.51 to 0.58 with two-stage separation. It is suggested that the aluminum removal by crystallization can evidently weaken the influence of aluminum co-extraction on vanadium extraction and improve the selectivity of solvent extraction for vanadium.

  5. Extraction mechanism of ultrasound assisted extraction and its effect on higher yielding and purity of artemisinin crystals from Artemisia annua L. leaves.

    Science.gov (United States)

    Chemat, Smain; Aissa, Abdallah; Boumechhour, Abdenour; Arous, Omar; Ait-Amar, Hamid

    2017-01-01

    This study proposes an ultrasound-horn system for the extraction of a natural active compound "artemisinin" from Artemisia annua L. leaves as an alternative to hot maceration technique. Ultrasound leaching improves artemisinin recovery at all temperatures where only ten minutes is required to recover 70% (4.42mgg(-1)) compared to 60min of conventional hot leaching for the same yield. For instance, ultrasound treatment at 30°C produced a higher yield than the one obtained by conventional maceration at 40°C. Kinetic study suggests that the extraction pattern can be assimilated, during the first ten minutes, to a first order steady state, from which activation energy calculations revealed that each gram of artemisinin required 7.38kJ in ultrasound versus 10.3kJ in the conventional system. Modeling results indicate the presence of two extraction stages, a faster stage with a diffusion coefficient of 19×10(-5)cm(2)min(-1) for ultrasound technique at 40°C, seven times higher than the conventional one; and a second deceleration stage similar for both techniques with diffusion coefficient ranging from 1.7 to 3.1×10(-5)cm(2)min(-1). It is noted that the efficient ultrasound extraction potential implies extraction of higher amount of co-metabolites so low artemisinin crystal purity is engendered but a combination with a purification step using activated charcoal and celite adsorbents produced crystals with comparable purity for conventional and ultrasound samples.

  6. Supercritical extraction of carqueja essential oil: experiments and modeling

    Directory of Open Access Journals (Sweden)

    R. M. F. Vargas

    2006-09-01

    Full Text Available Baccharis trimera is a native Brazilian plant which has medicinal properties. In this work a method of supercritical extraction was studied to obtain the popularly essential oil from Baccharis trimera, known as carqueja. The aim was to obtain experimental data and to compare two mathematical models used in the simulation of carqueja (Baccharis trimera oil extraction by supercritical CO2. The two mathematical models are based on mass transfer. One of the models, proposed by Reverchon, is solved numerically and requires two adjustable parameters from the experimental data. The other model chosen is the one proposed by Sovová. This model is solved analytically and requires four adjustable parameters. Numerical results are presented and discussed for the adjusted parameters. The experimental results are obtained in a temperature range of 313.15 K to 343.15 K at 90 bar. The extraction yield of carqueja essential oil using supercritical carbon dioxide ranged between 1.72 % (w/w at 323.15 K and 2.34 % (w/w at 343.15 K, 90 bar with a CO2 flow rate of 3.34.10-8 m³/s for a 0.0015 kg sample of Baccharis trimera.

  7. Purification, crystallization and preliminary X-ray diffraction experiment of nattokinase from Bacillus subtilis natto.

    Science.gov (United States)

    Yanagisawa, Yasuhide; Chatake, Toshiyuki; Chiba-Kamoshida, Kaori; Naito, Sawa; Ohsugi, Tadanori; Sumi, Hiroyuki; Yasuda, Ichiro; Morimoto, Yukio

    2010-12-01

    Nattokinase is a single polypeptide chain composed of 275 amino acids (molecular weight 27,724) which displays strong fibrinolytic activity. Moreover, it can activate other fibrinolytic enzymes such as pro-urokinase and tissue plasminogen activator. In the present study, native nattokinase from Bacillus subtilis natto was purified using gel-filtration chromatography and crystallized to give needle-like crystals which could be used for X-ray diffraction experiments. The crystals belonged to space group C2, with unit-cell parameters a=74.3, b=49.9, c=56.3 Å, β=95.2°. Diffraction images were processed to a resolution of 1.74 Å with an Rmerge of 5.2% (15.3% in the highest resolution shell) and a completeness of 69.8% (30.0% in the highest resolution shell). This study reports the first X-ray diffraction analysis of nattokinase.

  8. Resonant multi-turn extraction: Principle and experiments

    CERN Document Server

    Gilardoni, S S; Martini, M; Métral, E; Scaramuzzi, P; Steerenberg, R; Müller, A S

    2006-01-01

    Recently, a novel approach to perform multi-turn extraction was proposed based on beam splitting in the transverse phase space by means of trapping inside stable islands. In addition to numerical simulations, aimed at assessing the feasibility of the proposed technique, an experimental campaign was launched since the year 2002 at the CERN Proton Synchrotron. During the year 2004 run, a high-intensity single-bunch beam was successfully split and the generated beamlets separated without any measurable losses. The underlying principle will be presented and discussed in details in this paper, as well as the latest experimental results and future applications.

  9. Resonant Multi-Turn Extraction Principle and Experiments

    CERN Document Server

    Gilardoni, S S; Martini, M; Métral, E; Scaramuzzi, P; Steerenberg, R; Muller, AS

    2006-01-01

    Recently a novel approach to perform multi-turn extraction was proposed based on beam splitting in the transverse phase space by means of trapping inside stable islands. In addition to numerical simulations, aimed at assessing the feasibility of the proposed technique, an experimental campaign was launched since the year 2002 at the CERN Proton Synchrotron. During the year 2004 run, a high-intensity single-bunch beam was successfully split and the generated beamlets separated without any measurable losses. The underlying principle will be presented and discussed in details in this paper, as well as the latest experimental results and future applications.

  10. Optimization of Extraction Technology of Ellagic Acid from Pomegranate Peels with Orthogonal Experiment

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    [Objective] This study aimed to investigate the optimal condition for extrac- tion of ellagic acid from pomegranate peels. [Method] With ellagic acid yield as an indicator, ultrasound extraction method was adopted to extract the ellagic acid from pomegranate peels, and the concentration of ellagic acid was measured by using ul- traviolet spectrophotometry; L9(34) orthogonal experiment was designed with four fac- tors at three levels, to investigate the effect of extraction temperature, extraction du- ration, solid-liquid ratio and ultrasound power on extraction rate of ellagic acid. [Re- sult] The optimal extraction condition for ellagic acid is extraction temperature of 30 ~C, solid-liquid ratio of 1:200, extraction duration of 20 min, and ultrasound power of 50 W. The relationship between primary and secondary factors affecting experimental indicators was solid-liquid ratio 〉 extraction duration 〉 ultrasound power 〉 extraction temperature. [Conclusion] Solid-liquid ratio has the maximum effect on extraction rate of ellagic acid. The ellagic acid extraction technology identified in this study is rea- sonable and feasible.

  11. An optimized affordable DNA-extraction method from Salmonella enterica Enteritidis for PCR experiments

    Directory of Open Access Journals (Sweden)

    Karimnasab, N.,

    2013-12-01

    Full Text Available In diagnostic and research bacteriology settings with budget and staff restrictions, fast and cost-effective genome extraction methods are desirable. If not inactivated properly, cellular and/or environmental DNA nucleases will degrade genomic material during the extraction stage, and therefore might give rise to incorrect results in PCR experiments. When crude cell extracts, proteinase K–treated templates and purified DNAs prepared by phenol-chloroform-isoamylalcohol method as well as a commercial extraction kit were subjected to the Salmonella enterica Enteritidis specific STM2 PCR, with exception of crude cell extract, PCR products from all other three methods saved their integrity for 28 days post-generation. This work aimed to find out whether improvement to boiling method can guaranty stability of PCR products. As results showed, treatment of crude cell extracts from S. Enteritidis with proteinase K offers an inexpensive, fast and effective DNA extraction method suitable for high-throughput laboratories.

  12. Performance study of single undoped CsI crystals for the Mu2e experiment

    CERN Document Server

    Donghia, Raffaella

    2016-01-01

    The Mu2e experiment at Fermilab aims to measure the charged lepton flavor violating neutrinoless muon to electron conversion. The goal of the experiment is to reach a single event sensitivity of 2.5 x 10^{-17}, to set an upper limit on the muon conversion rate at 6.7 x 10^{-17} in a three years run. For this purpose, the Mu2e detector is designed to identify electrons from muon conversion and reduce the background to a negligible level. It consists of a low mass straw tracker and a pure CsI crystal calorimeter. In this paper, the performance of undoped CsI single crystal is reported. Crystals from many vendors have been characterized by determining their Light Yield (LY) and Longitudinal Response Uniformity (LRU), when read with a UV extended PMT, and their time resolution when coupled to a Silicon Photomultiplier. The crystals show a LY of ~ 100 photoelectrons per MeV when wrapped with Tyvek and coupled to the PMT without optical grease. The LRU is well represented by a linear slope that is on average 0.6%/c...

  13. Applying design of experiments (DOE to flavonoid extraction from Passiflora alata and P. edulis

    Directory of Open Access Journals (Sweden)

    Peky Noriega

    2012-10-01

    Full Text Available The Passifloraceae family is extensively used in native Brazilian folk medicine to treat a wide variety of diseases. The problem of flavonoid extraction from Passiflora was treated by application of design of experiments (DOE, as an experiment with mixture including one categorical process variable. The components of the binary mixture were: ethanol (component A and water (component B; the categorical process variable: extraction method (factor C was varied at two levels: (+1 maceration and (-1 percolation. ANOVA suggested a cubic model for P. edulis extraction and a quadratic model for P. alata.These results indicate that the proportion of components A and B in the mixture is the main factor involved in significantly increasing flavonoid extraction. In regard to the extraction methods, no important differences were observed, which indicates that these two traditional extraction methods could be effectively used to extract flavonoids from both medicinal plants. The evaluation of antioxidant activity of the extract by ORAC method showed that P. edulis displays twice as much antioxidant activity as P. alata. Considering that maceration is a simple, rapid and environmentally friendly extraction method, in this study, the optimized conditions for flavonoid extraction from these Passiflora species is maceration with 75% ethanol for P. edulis and 50% ethanol for P. alata.

  14. Preparation and characterization of single crystal samples for high-pressure experiments

    Energy Technology Data Exchange (ETDEWEB)

    Farber, D; Antonangeli, D; Aracne, C; Benterou, J

    2005-10-26

    To date, most research utilizing the diamond anvil cell (DAC) has been conducted with polycrystalline samples, thus the results are limited to addressing average bulk properties. However, experiments on single crystals can yield data on a range of orientation dependent properties such as thermal and electrical conductivity, magnetic susceptibility, elasticity and plasticity. Here we report new procedures to produce extremely high-quality metallic single crystal samples of size compatible with DAC experiments in the Mbar range. So far, we have produced samples of zinc, Al{sub 2}O{sub 3}, cobalt, molybdenum and cerium, and have evaluated the quality of the finished samples with white-light interferometry, synchrotron x-ray diffraction and inelastic x-ray scattering.

  15. Effects of Extract from Mangifera indica Leaf on Monosodium Urate Crystal-Induced Gouty Arthritis in Rats

    Directory of Open Access Journals (Sweden)

    Yan Jiang

    2012-01-01

    Full Text Available The leaves of Mangifera indica L. (Anacardiaceae is used as a medicinal material in traditional herb medicine for a long time in India, China, and other Eastern Asian countries. Our present study investigated the therapeutic effects of the ethanol extract from Mangifera indica (EMI in rat with monosodium urate (MSU crystals-induced gouty arthritis. Effects of EMI (50, 100, and 200 mg/kg, p.o. administrated for 9 days on the ankle swelling, synovial tumor necrosis factor-alpha (TNF-α, and interleukin-1beta (IL-1β levels were assessed in MSU crystal rat. Data from our study showed that rat with gouty arthritis induced by MSU crystal demonstrated an elevation in ankle swelling, synovial TNF-α, IL-1β mRNA, and protein levels. Oral administration of 100 and 200 mg/kg EMI for 9 days reversed the abnormalities in ankle swelling, synovial TNF-α, IL-1β mRNA, and protein levels. The results indicated that the beneficial antigouty arthritis effect of EMI may be mediated, at least in part, by inhibiting TNF-α and IL-1β expression in the synovial tissues. Our study suggests that Mangifera indica and its extract may have a considerable potential for development as an anti-gouty arthritis agent for clinical application.

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

    CERN Document Server

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

    2013-01-01

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

  17. Crystallization In High Level Waste (HLW) Glass Melters: Operational Experience From The Savannah River Site

    Energy Technology Data Exchange (ETDEWEB)

    Fox, K. M.

    2014-02-27

    processing strategy for the Hanford Tank Waste Treatment and Immobilization Plant (WTP). The basis of this alternative approach is an empirical model predicting the crystal accumulation in the WTP glass discharge riser and melter bottom as a function of glass composition, time, and temperature. When coupled with an associated operating limit (e.g., the maximum tolerable thickness of an accumulated layer of crystals), this model could then be integrated into the process control algorithms to formulate crystal tolerant high level waste (HLW) glasses targeting higher waste loadings while still meeting process related limits and melter lifetime expectancies. This report provides a review of the scaled melter testing that was completed in support of the Defense Waste Processing Facility (DWPF) melter. Testing with scaled melters provided the data to define the DWPF operating limits to avoid bulk (volume) crystallization in the un-agitated DWPF melter and provided the data to distinguish between spinels generated by K-3 refractory corrosion versus spinels that precipitated from the HLW glass melt pool. This report includes a review of the crystallization observed with the scaled melters and the full scale DWPF melters (DWPF Melter 1 and DWPF Melter 2). Examples of actual DWPF melter attainment with Melter 2 are given. The intent is to provide an overview of lessons learned, including some example data, that can be used to advance the development and implementation of an empirical model and operating limit for crystal accumulation for WTP. Operation of the first and second (current) DWPF melters has demonstrated that the strategy of using a liquidus temperature predictive model combined with a 100 °C offset from the normal melter operating temperature of 1150 °C (i.e., the predicted liquidus temperature (TL) of the glass must be 1050 °C or less) has been successful in preventing any detrimental accumulation of spinel in the DWPF melt pool, and spinel has not been

  18. Enhanced Extraction of Silicon-Vacancy Centers Light Emission Using Bottom-Up Engineered Polycrystalline Diamond Photonic Crystal Slabs.

    Science.gov (United States)

    Ondič, Lukáš; Varga, Marian; Hruška, Karel; Fait, Jan; Kapusta, Peter

    2017-03-28

    Silicon vacancy (SiV) centers are optically active defects in diamond. The SiV centers, in contrast to nitrogen vacancy (NV) centers, possess narrow and efficient luminescence spectrum (centered at ≈738 nm) even at room temperature, which can be utilized for quantum photonics and sensing applications. However, most of light generated in diamond is trapped in the material due to the phenomenon of total internal reflection. In order to overcome this issue, we have prepared two-dimensional photonic crystal slabs from polycrystalline diamond thin layers with high density of SiV centers employing bottom-up growth on quartz templates. We have shown that the spectral overlap between the narrow light emission of the SiV centers and the leaky modes extracting the emission into almost vertical direction (where it can be easily detected) can be obtained by controlling the deposition time. More than 14-fold extraction enhancement of the SiV centers photoluminescence was achieved compared to an uncorrugated sample. Computer simulation confirmed that the extraction enhancement originates from the efficient light-matter interaction between light emitted from the SiV centers and the photonic crystal slab.

  19. Extraction of coherent structures in a rotating turbulent flow experiment

    CERN Document Server

    Ruppert-Felsot, J E; Sharon, E; Swinney, H L; Ruppert-Felsot, Jori E.; Praud, Olivier; Sharon, Eran; Swinney, Harry L.

    2004-01-01

    The discrete wavelet packet transform (DWPT) and discrete wavelet transform (DWT) are used to extract and study the dynamics of coherent structures in a turbulent rotating fluid. Three-dimensional (3D) turbulence is generated by strong pumping through tubes at the bottom of a rotating tank (48.4 cm high, 39.4 cm diameter). This flow evolves toward two-dimensional (2D) turbulence with increasing height in the tank. Particle Image Velocimetry (PIV) measurements on the quasi-2D flow reveal many long-lived coherent vortices with a wide range of sizes. The vorticity fields exhibit vortex birth, merger, scattering, and destruction. We separate the flow into a low-entropy ``coherent'' and a high-entropy ``incoherent'' component by thresholding the coefficients of the DWPT and DWT of the vorticity fields. Similar thresholdings using the Fourier transform and JPEG compression together with the Okubo-Weiss criterion are also tested for comparison. We find that the DWPT and DWT yield similar results and are much more ef...

  20. Effect of extract of Phyllanthus niruri on crystal deposition in experimental urolithiasis.

    Science.gov (United States)

    Barros, Marcio E; Lima, Roberta; Mercuri, Lucildes P; Matos, Jivaldo R; Schor, Nestor; Boim, Mirian A

    2006-12-01

    Phyllanthus niruri (Pn) is a plant that has been shown to interfere in the growth and aggregation of calcium oxalate (CaOx) crystals. In the present study we evaluated the effect of Pn on the preformed calculus induced by introduction of a CaOx seed into the bladder of male Wistar rats. Pn treatment (5 mg/ rat/day) was initiated immediately or 30 days after CaOx seeding and thus in the presence of a preformed calculus. Animals were sacrificed 50 or 70 days after surgery. The resulting calculi were weighed and analyzed by X-ray diffraction, stereomicroscopy and scanning electronic microscopy. Precocious Pn treatment reduced the number (75%, P struvite crystals over the CaOx seed and Pn did not change the crystalline composition of the calculi. This suggests that Pn interfered with the arrangement of the precipitating crystals, probably by modifying the crystal-crystal and/or crystal-matrix interactions. Results suggest that Pn may have a therapeutic potential, since it was able to modify the shape and texture of calculi to a smoother and probably more fragile form, which could contribute to elimination and/or dissolution of calculi.

  1. Deformation twinning in small-sized face-centred cubic single crystals: Experiments and modelling

    Science.gov (United States)

    Liang, Z. Y.; Huang, M. X.

    2015-12-01

    Small-sized crystals generally show deformation behaviour distinct from their bulk counterparts. In addition to dislocation slip, deformation twinning in small-sized face-centred cubic (FCC) single crystals has been reported to follow a different mechanism which involves coherent emission of partial dislocations on successive { 111 } planes from free surface. The present work employed a twinning-induced plasticity (TWIP) steel with a low stacking fault energy to systematically investigate the twin evolution in small-sized FCC single crystals. Micrometre-sized single crystal pillars of TWIP steel were fabricated by focus ion beam and then strained to different levels by compression experiments. Detailed transmission electron microscopy characterization was carried out to obtain a quantitative evaluation of the deformation twins, which contribute to most of the plastic strain. Emissions of partial dislocations from free surface (surface sources) and pre-existing perfect dislocations inside the pillar (inner sources) are found as the essential processes for the formation of deformation twins. Accordingly, a physically-based model, which integrates source introduction methods and source activation criterions for partial dislocation emission, is developed to quantitatively predict the twin evolution. The model is able to reproduce the experimental twin evolution, in terms of the total twin formation, the twin morphology and the occurrence of twinning burst.

  2. Emission cross sections and energy extraction for the mid-infrared transitions of Er, Tm, and Ho in oxide and fluoride crystals

    Science.gov (United States)

    Chase, L. L.; Payne, S. A.; Smith, L. K.; Kway, W. L.; Krupke, W. F.

    Emission cross sections have been measured for the transitions between the two lowest spin orbit multiplets of Er, Tm, and Ho in several fluoride and oxide crystals. Properties affecting energy extraction efficiency are summarized and pulsed extraction performance is calculated for several of these quasi-three-level laser media.

  3. Effect of crystal shape on neutron rocking curves of perfect single crystals designed for ultra-small-angle scattering experiments

    Science.gov (United States)

    Freund, A. K.; Rehm, C.

    2014-07-01

    The present study has been conducted in the framework of the channel-cut crystal design for the Kookaburra ultra-small-angle neutron scattering (USANS) instrument to be installed at the OPAL reactor of ANSTO. This facility is based on the classical Bonse-Hart method that uses two multiple-reflection crystal systems. The dynamical theory of diffraction by perfect crystals distinguishes two cases: the Darwin case applying to infinitely thick crystals and the Ewald solution for very small absorption taking into account the reflection from the rear face of a plane-parallel crystal reflecting in Bragg geometry. The former is preferable because it yields narrower rocking curves. To prevent the neutrons to "see" the rear face, grooves were machined into the backside of perfect Si test crystals for single reflection and filled with neutron absorbing material. These samples were examined at the S18 instrument of the Institut Laue-Langevin. Unexpectedly the crystals with empty slots showed an increase of the rocking curve width. When filling the slots with an absorber the widths decreased, but without reaching that of the Darwin curve. Understanding the results and achieving a successful crystal design call for the development of a theory that permits to describe neutron diffraction from crystals with a structured back face.

  4. Guided mode extraction in monolayer colloidal crystals based on the phase variation of reflection and transmission coefficients

    Science.gov (United States)

    Nekuee, Seyed Amir Hossein; Akbari, Mahmood; Khavasi, Amin

    2016-04-01

    An accurate and fast method for guided modes extraction in monolayer colloidal crystals and their inverse replicas is presented. These three-dimensional structures are composed of a monolayer of spherical particles that can easily and simply be prepared by self-assembly method in close packed hexagonal lattices. In this work, we describe how the guided modes, even or odd modes and light cone boundary can be easily determined using phase variations of reflection and transmission coefficients. These coefficients are quickly calculated by Fourier modal method. The band structures are obtained for a monolayer of polystyrene particles and two-dimensional TiO2 inverse opal by this proposed method.

  5. Crystallization from Gels

    Science.gov (United States)

    Narayana Kalkura, S.; Natarajan, Subramanian

    Among the various crystallization techniques, crystallization in gels has found wide applications in the fields of biomineralization and macromolecular crystallization in addition to crystallizing materials having nonlinear optical, ferroelectric, ferromagnetic, and other properties. Furthermore, by using this method it is possible to grow single crystals with very high perfection that are difficult to grow by other techniques. The gel method of crystallization provides an ideal technique to study crystal deposition diseases, which could lead to better understanding of their etiology. This chapter focuses on crystallization in gels of compounds that are responsible for crystal deposition diseases. The introduction is followed by a description of the various gels used, the mechanism of gelling, and the fascinating phenomenon of Liesegang ring formation, along with various gel growth techniques. The importance and scope of study on crystal deposition diseases and the need for crystal growth experiments using gel media are stressed. The various crystal deposition diseases, viz. (1) urolithiasis, (2) gout or arthritis, (3) cholelithiasis and atherosclerosis, and (4) pancreatitis and details regarding the constituents of the crystal deposits responsible for the pathological mineralization are discussed. Brief accounts of the theories of the formation of urinary stones and gallstones and the role of trace elements in urinary stone formation are also given. The crystallization in gels of (1) the urinary stone constituents, viz. calcium oxalate, calcium phosphates, uric acid, cystine, etc., (2) the constituents of the gallstones, viz. cholesterol, calcium carbonate, etc., (3) the major constituent of the pancreatic calculi, viz., calcium carbonate, and (4) cholic acid, a steroidal hormone are presented. The effect of various organic and inorganic ions, trace elements, and extracts from cereals, herbs, and fruits on the crystallization of major urinary stone and gallstone

  6. CMS Pixel Telescope Addition to T-980 Bent Crystal Collimation Experiment at the Tevatron

    CERN Document Server

    Rivera, Ryan; Johnson, Todd; Kwan, Simon; Lundberg, Carl; Still, Dean; Prosser, Alan; Uplegger, Lorenzo; Zagel, Jim; Zvodaya, Viktoriya

    2012-01-01

    An enhancement to the T-980 bent crystal collimation experiment at the Tevatron has been completed. The enhancement was the installation of a pixel telescope inside the vacuum-sealed beam pipe of the Tevatron. The telescope is comprised of six CMS PSI46 pixel plaquettes, arranged as three stations of horizontal and vertical planes, with the CAPTAN system for data acquisition and control. The purpose of the pixel telescope is to measure beam profiles produced by bent crystals under various conditions. The telescope electronics inside the beam pipe initially were not adequately shielded from the image current of the passing beams. A new shielding approach was devised and installed, which resolved the problem. The noise issues encountered and the mitigating techniques are presented herein, as well as some preliminary results from the telescope.

  7. CMS Pixel Telescope Addition to T-980 Bent Crystal Collimation Experiment at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Rivera, Ryan; Annala, Jerry; Johnson, Todd; Kwan, Simon; Lundberg, Carl; Still, Dean; Prosser, Alan; Uplegger, Lorenzo; Zagel, Jim; Zvodaya, Viktoriya; /Fermilab

    2011-09-14

    An enhancement to the T-980 bent crystal collimation experiment at the Tevatron has been completed. The enhancement was the installation of a pixel telescope inside the vacuum-sealed beam pipe of the Tevatron. The telescope is comprised of six CMS PSI46 pixel plaquettes, arranged as three stations of horizontal and vertical planes, with the CAPTAN system for data acquisition and control. The purpose of the pixel telescope is to measure beam profiles produced by bent crystals under various conditions. The telescope electronics inside the beam pipe initially were not adequately shielded from the image current of the passing beams. A new shielding approach was devised and installed, which resolved the problem. The noise issues encountered and the mitigating techniques are presented herein, as well as some preliminary results from the telescope.

  8. Formation of Cosmic String network from black holes: Implications from liquid crystal experiments

    CERN Document Server

    Srivastava, A M

    2006-01-01

    We present observation of large, expanding string loops forming around a heated wire tip embedded in a nematic liquid crystal sample. Loops expand due to convective stretching. This observation leads to a new insight into phenomena which could occur in the early universe. We show that local heating of plasma in the early universe by evaporating primordial black holes can lead to formation of large, expanding cosmic string loops, just as observed in the liquid crystal experiment. Intercommutation of string loops from neighboring black holes can lead to percolation, thereby forming an infinite string network. This is remarkable as such an infinite string network is thought to arise only when the entire universe undergoes phase transition.

  9. Purification of precursors of Yb3+-doped YLF crystals by solvent extraction and electrochemical processing

    Science.gov (United States)

    Boncher, William L.; Judge, Elizabeth; Sansinena, Jose-Maria; Dirmyer, Matthew R.; Hehlen, Markus P.

    2015-03-01

    Optical refrigeration by laser irradiation of YLiF4:Yb3+ (YLF:Yb) crystals has been shown to be strongly deteriorated by impurities, which absorb energy at the laser wavelength, and relax non-radiatively, negating cooling produced from anti-Stokes fluorescence. We aim to increase the efficiency of optical refrigeration through materials purification. We start with the purest sources commercially available and process them in a cleanroom environment. Our method proceeds through electrochemical purification, separating out the transition metal impurities by their redox potentials, and can be scaled up to produce the amounts of material needed for crystal growth.

  10. Application of PbWO4 crystal scintillators in experiment to search for double beta decay of 116Cd

    CERN Document Server

    Danevich, F A; Kobychev, V V; Kropivyansky, B N; Nagorny, S S; Nikolaiko, A S; Poda, D V; Tretyak, V I; Yurchenko, S S; Grinyov, B V; Nagornaya, L L; Pirogov, E N; Ryzhikov, V D; Brudanin, V B; Fedorov, M; Korzhik, M; Lobko, A; Miussevitch, O; Solsky, I M

    2004-01-01

    PbWO4 crystal scintillators are discussed as an active shield and light-guides in 116Cd double beta decay experiment with CdWO4 scintillators. Scintillation properties and radioactive contamination of PbWO4 scintillators were investigated. Energy resolution of CdWO4 detector, coupled to PbWO4 crystal as a light-guide, was tested. Efficiency of PbWO4-based active shield to suppress background from the internal contamination of PbWO4 crystals was calculated. Using of lead tungstate crystal scintillators as high efficiency 4-pi active shield could allow to build sensitive double beta experiment with 116CdWO4 crystal scintillators.

  11. Macromolecular Crystallization in Microgravity

    Science.gov (United States)

    Snell, Edward H.; Helliwell, John R.

    2004-01-01

    The key concepts that attracted crystal growers, macromolecular or solid state, to microgravity research is that density difference fluid flows and sedimentation of the growing crystals are greatly reduced. Thus, defects and flaws in the crystals can be reduced, even eliminated, and crystal volume can be increased. Macromolecular crystallography differs from the field of crystalline semiconductors. For the latter, crystals are harnessed for their electrical behaviors. A crystal of a biological macromolecule is used instead for diffraction experiments (X-ray or neutron) to determine the three-dimensional structure of the macromolecule. The better the internal order of the crystal of a biological macromolecule then the more molecular structure detail that can be extracted. This structural information that enables an understanding of how the molecule functions. This knowledge is changing the biological and chemical sciences with major potential in understanding disease pathologies. Macromolecular structural crystallography in general is a remarkable field where physics, biology, chemistry, and mathematics meet to enable insight to the basic fundamentals of life. In this review, we examine the use of microgravity as an environment to grow macromolecular crystals. We describe the crystallization procedures used on the ground, how the resulting crystals are studied and the knowledge obtained from those crystals. We address the features desired in an ordered crystal and the techniques used to evaluate those features in detail. We then introduce the microgravity environment, the techniques to access that environment, and the theory and evidence behind the use of microgravity for crystallization experiments. We describe how ground-based laboratory techniques have been adapted to microgravity flights and look at some of the methods used to analyze the resulting data. Several case studies illustrate the physical crystal quality improvements and the macromolecular structural

  12. Extraction of the beta-factor for single quantum dots coupled to a photonic crystal waveguide

    DEFF Research Database (Denmark)

    Nielsen, Henri Thyrrestrup; Sapienza, Luca; Lodahl, Peter

    2010-01-01

    We present measurements of the β-factor, describing the coupling efficiency of light emitted by single InAs/GaAs semiconductor quantum dots into a photonic crystal waveguide mode. The β-factor is evaluated by means of time resolved frequency-dependent photoluminescence spectroscopy. The emission...

  13. PKE-Nefedov: plasma crystal experiments on the International Space Station

    Energy Technology Data Exchange (ETDEWEB)

    Nefedov, Anatoli P [Institute for High Energy Densities, Russian Academy of Sciences, 127412 Moscow (Russian Federation); Morfill, Gregor E [Centre for Interdisciplinary Plasma Science, Max-Planck-Institut fuer Extraterrestrische Physik, D-85740 Garching (Germany); Fortov, Vladimir E [Institute for High Energy Densities, Russian Academy of Sciences, 127412 Moscow (Russian Federation); Thomas, Hubertus M [Centre for Interdisciplinary Plasma Science, Max-Planck-Institut fuer Extraterrestrische Physik, D-85740 Garching (Germany); Rothermel, Hermann [Centre for Interdisciplinary Plasma Science, Max-Planck-Institut fuer Extraterrestrische Physik, D-85740 Garching (Germany); Hagl, Tanja [Centre for Interdisciplinary Plasma Science, Max-Planck-Institut fuer Extraterrestrische Physik, D-85740 Garching (Germany); Ivlev, Alexei V [Centre for Interdisciplinary Plasma Science, Max-Planck-Institut fuer Extraterrestrische Physik, D-85740 Garching (Germany); Zuzic, Milenko [Centre for Interdisciplinary Plasma Science, Max-Planck-Institut fuer Extraterrestrische Physik, D-85740 Garching (Germany); Klumov, Boris A [Centre for Interdisciplinary Plasma Science, Max-Planck-Institut fuer Extraterrestrische Physik, D-85740 Garching (Germany); Lipaev, Andrey M [Institute for High Energy Densities, Russian Academy of Sciences, 127412 Moscow (Russian Federation); Molotkov, Vladimir I [Institute for High Energy Densities, Russian Academy of Sciences, 127412 Moscow (Russian Federation); Petrov, Oleg F [Institute for High Energy Densities, Russian Academy of Sciences, 127412 Moscow (Russian Federation); Gidzenko, Yuri P [Y Gagarin Cosmonauts Training Centre, 141160 Star City, Moscow Region (Russian Federation); Krikalev, Sergey K [SP Korolev RSC Energia, Korolev 141070, Moscow Region (Russian Federation); Shepherd, William [Expedition 1 Crew, International Space Station (ISS) (Country Unknown)] [and others

    2003-04-01

    The plasma crystal experiment PKE-Nefedov, the first basic science experiment on the International Space Station (ISS), was installed in February 2001 by the first permanent crew. It is designed for long-term investigations of complex plasmas under microgravity conditions. 'Complex plasmas' contain ions, electrons, neutrals and small solid particles - normally in the micrometre range. These microparticles obtain thousands of elementary charges and interact with each other via a 'screened' Coulomb potential. Complex plasmas are of special interest, because they can form liquid and crystalline states (Thomas et al 1994 Phys. Rev. Lett. 73 652-5, Chu and I 1994 Phys. Rev. Lett. 72 4009-12) and are observable at the kinetic level. In experiments on Earth the microparticles are usually suspended against gravity in strong electric fields. This creates asymmetries, stresses and pseudo-equilibrium states with sufficient free energy to readily become unstable. Under microgravity conditions the microparticles move into the bulk of the plasma (Morfill et al 1999 Phys. Rev. Lett. 83 1598), experiencing much weaker volume forces than on Earth. This allows investigations of the thermodynamics of strongly coupled plasma states under substantially stress-free conditions. In this first paper we report our results on plasma crystals, in particular the first experimental observations of bcc lattice structures.

  14. Parasitic extraction of 900-GeV/c protons from the Tevatron using a bent silicon crystal and measurement of the $b \\bar{b}$ production cross-section at $\\sqrt{s}$ = 38.8-GeV

    Energy Technology Data Exchange (ETDEWEB)

    Ramachandran, Sathyadev [Univ. of California, Los Angeles, CA (United States)

    1997-01-01

    This dissertation discusses results from an experiment demonstrating the feasibility of a novel extraction scheme using channeling in a bent crystal at future high-energy colliders for doing heavy avor physics in a xed target environment concurrently with collider experiments. In the second half of this dissertation we present the results from a measurement of the inclusive cross-section for b$\\bar{b}$ production at the center-of-mass energy of 38.8 GeV using the semileptonic decays of the beauty mesons.

  15. Single-photon experiments with liquid crystals for quantum science and quantum engineering applications

    Science.gov (United States)

    Lukishova, Svetlana G.; Liapis, Andreas C.; Bissell, Luke J.; Gehring, George M.; Winkler, Justin M.; Boyd, Robert W.

    2015-03-01

    We present here our results on using liquid crystals in experiments with nonclassical light sources: (1) single-photon sources exhibiting antibunching (separation of all photons in time), which are key components for secure quantum communication systems, and (2) entangled photon source with photons exhibiting quantum interference in a Hong-Ou- Mandel interferometer. In the first part, cholesteric liquid crystal hosts were used to create definite circular polarization of antibunched photons emitted by nanocrystal quantum dots. If the photon has unknown polarization, filtering it through a polarizer to produce the desired polarization for quantum key distribution with bits based on polarization states of photons will reduce by half the efficiency of a quantum cryptography system. In the first part, we also provide our results on observation of a circular polarized microcavity resonance in nanocrystal quantum dot fluorescence in a 1-D chiral photonic bandgap cholesteric liquid crystal microcavity. In the second part of this paper with indistinguishable, time-entangled photons, we demonstrate our experimental results on simulating quantum-mechanical barrier tunnelling phenomena. A Hong-Ou-Mandel dip (quantum interference effect) is shifted when a phase change was introduced on the way of one of entangled photons in pair (one arm of the interferometer) by inserting in this arm an electrically controlled planar-aligned nematic liquid crystal layer between two prisms in the conditions close to a frustrated total internal reflection. By applying different AC-voltages to the planar-aligned nematic layer and changing its refractive index, we can obtain various conditions for incident photon propagation - from total reflection to total transmission. Measuring changes of tunnelling times of photon through this structure with femtosecond resolution permitted us to answer some unresolved questions in quantum-mechanical barrier tunnelling phenomena.

  16. Crystallization In High Level Waste (HLW) Glass Melters: Operational Experience From The Savannah River Site

    Energy Technology Data Exchange (ETDEWEB)

    Fox, K. M.

    2014-02-27

    Include noble metals in glass melt experiments because of their potential to act as nucleation sites for spinel crystallization.

  17. Study on Extracting Low Concentration Cadmium from Zinc Hydrometallurgy System by Liquid Membrane Crystallizing Technique

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The extraction of low concentration cadmium from a system containing high concentration zinc was studied and got CdS product directly. A new liquid membrane system taking DIPSA, TIBPS as carriers, (NH4)2S as precipitating agent was reported. Precipitating Cd2+ in the internal aq. phase that is used to treat sulfuric acid leaching solution of zinc oxide in zinc hydrometallurgy has gotten satisfied results of extracting cadmium from high concentration zinc. After one-stage of batch process under the optimum liquid membrane conditions, 98.6% transferring rate and 98.1% extracting rate of cadmium was obtained with only less than 1.0% transferring rate of zinc, and the feed solution can be purified very well.

  18. Protein crystallization under microgravity conditions. Analysis of the results of Russian experiments performed on the International Space Station in 2005-2015

    Science.gov (United States)

    Boyko, K. M.; Timofeev, V. I.; Samygina, V. R.; Kuranova, I. P.; Popov, V. O.; Koval'chuk, M. V.

    2016-09-01

    Conditions of mass transport to growing crystals have a considerable effect on the crystal size and quality. The reduction of convective transport can help improve the quality of crystals for X-ray crystallography. One approach to minimizing convective transport is crystallization in a microgravity environment, in particular, in space. The data obtained by our research team in protein crystallization experiments on the International Space Station are surveyed and analyzed.

  19. Formation of the Yandangshan volcanic-plutonic complex (SE China) by melt extraction and crystal accumulation

    Science.gov (United States)

    Yan, Li-Li; He, Zhen-Yu; Jahn, Bor-ming; Zhao, Zhi-Dan

    2016-12-01

    The association of volcanic and shallow plutonic rocks in caldera may provide important clues to the geochemical evolution of silicic magma systems. The Yandangshan caldera is a typical example of late Mesozoic volcanic-plutonic complex in SE China. It is composed of a series of rhyolitic extrusives and subvolcanic intrusions of porphyritic quartz syenites. In this work, we conducted petrological and geochemical studies, as well as zircon dating, on the coexisting volcanic and plutonic rocks from the Yandangshan caldera. The results of SHRIMP and LA-ICP-MS zircon U-Pb dating revealed that the crystallization of the rhyolitic extrusives and subvolcanic intrusions was contemporaneous within analytical errors and in a short period (104-98 Ma). Geochemically, the volcanic rocks are characterized by high Rb/Sr and Rb/Ba ratios and depletion in Ba, Sr, P, Eu and Ti, while the shallow plutons show high K, Ba, Al, Fe and low Rb/Sr and Rb/Ba ratios with insignificant negative Eu anomalies. The volcanic and plutonic rocks have a similar range of zircon Hf isotopic compositions (εHf(t) = - 10.0 to + 1.5) and TDM2 model ages of 2.10-1.23 Ga. They also have comparable whole-rock Sr and Nd isotopic compositions ((87Sr/86Sr)i = 0.7084-0.7090; εNd(t) = - 7.8 to - 6.5) and zircon oxygen isotopic compositions (δ18O mainly = 4.5 to 6.0‰). We argue that the volcanic-plutonic complex of the Yandangshan caldera was formed by reworking of Paleoproterozoic lower crusts in the eastern Cathaysia block, and that the complex could be linked by fractional crystallization and crystal accumulation in a shallow magma chamber. The volcanic rocks represent the highly fractionated end-member, whereas the subvolcanic intrusions of porphyritic quartz syenites could be the residual crystal mushes. This case study could have a general implication for the genetic relationship between volcanic and shallow plutonic rocks in calderas.

  20. Improving Light Extraction of Organic Light-Emitting Devices by Attaching Nanostructures with Self-Assembled Photonic Crystal Patterns

    Directory of Open Access Journals (Sweden)

    Kai-Yu Peng

    2014-01-01

    Full Text Available A single-monolayered hexagonal self-assembled photonic crystal (PC pattern fabricated onto polyethylene terephthalate (PET films by using simple nanosphere lithography (NSL method has been demonstrated in this research work. The patterned nanostructures acted as a scattering medium to extract the trapped photons from substrate mode of optical-electronic device for improving the overall external quantum efficiency of the organic light-emitting diodes (OLEDs. With an optimum latex concentration, the distribution of self-assembled polystyrene (PS nanosphere patterns on PET films can be easily controlled by adjusting the rotation speed of spin-coater. After attaching the PS nanosphere array brightness enhancement film (BEF sheet as a photonic crystal pattern onto the device, the luminous intensity of OLEDs in the normal viewing direction is 161% higher than the one without any BEF attachment. The electroluminescent (EL spectrum of OLEDs with PS patterned BEF attachment also showed minor color offset and superior color stabilization characteristics, and thus it possessed the potential applications in all kinds of display technology and solid-state optical-electronic devices.

  1. Crystallization of silver through reduction process using Elaeis guineensis biosolid extract.

    Science.gov (United States)

    Velmurugan, Palanivel; Shim, Jaehong; Kamala-Kannan, Seralathan; Lee, Kui-Jae; Oh, Byung-Taek; Balachandar, Vellingiri; Oh, Byung-Taek

    2011-01-01

    This study presents a special, economically valuable, unprecedented eco-friendly green process for the synthesis of silver nanoparticles. The silver nanoparticles were obtained from a waste material with oil palm biosolid extract as the reducing agent. The use of the oil palm biosolid extract for the nanoparticle synthesis offers the benefit of amenability for large-scale production. An aqueous solution of silver (Ag(+) ) ions was treated with the oil palm biosolid extract for the formation of Ag nanoparticles. The nanometallic dispersion was characterized by surface plasmon absorbance measuring 428 nm. Transmission electron microscopy showed the formation of silver nanoparticles in the range of 5-50 nm. Scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) and X-ray diffraction analysis of the freeze-dried powder confirmed the formation of metallic silver nanoparticles. Moreover, Fourier Transform Infrared Spectroscopy provided evidence of phenolics or proteins as the biomolecules that were likely responsible for the reduction and capping agent, which helps to increase the stability of the synthesized silver nanoparticles. In addition, we have optimized the production with various parameters. Copyright © 2010 American Institute of Chemical Engineers (AIChE).

  2. Comparison of the inhibitory capacity of two groups of pure natural extract on the crystallization of two types of material compound urinary stones in vitro study

    Science.gov (United States)

    Beghalia, Mohamed; Ghalem, Said; Allali, Hocine

    2015-10-01

    Urolithiasis is defined as the result of an abnormal precipitation within the urinary tract. This precipitation is most often from the normal constituents of the urine. This is a fairly common condition in the population. She is happy and recurrent etiology is often unknown if hypothetical. In Algeria, as in many countries, a large number of patients use herbal medicines in the treatment of their diseases including urolithiasis. Thus the aim of this study is the most widely used to evaluate the effectiveness of aqueous extracts of medicinal plants, in the treatment of calcium urolithiasis oxalo-and magnesium-amoniaco in vitro. The study also examines the effect of these extracts on the states of crystallization (nucleation, crystal growth, crystal aggregation), followed by photography on polarized light microscope.In this regard, we are devoted to studying the crystallization steps from oxalo-calcium and phospho-calcic prepared as artificial urine and supersaturated aqueous solutions, maintained at 37 °C to remain close to biological conditions. Extracts of the first group of herbs: Ammodaucus leucotrichus, Ajuga iva, Globularia alypum, Atriplex halimus are studied on the crystallization calcium oxalate, we cite the Ammodaucus leucotrichus which acts on the stages of nucleation, growth and the aggregation with a total inhibition. The second group of extracts plants tested on calcium phosphate crystallization : Acacia raddiana, Citrullus colocynthis, Rhus tripartita, Pistacia lentiscu, Warionia saharae, are able to significantly reduce phosphate crystallization in vitro. It is easily proved by FTIR and optical microscope. In conclusion the results of our work allows us to confirm the use of these plants as an aqueous decoction, in the field of urolithiasis. These activities may help to strengthen the body in depressed situations.

  3. Macromolecular crystallization in microgravity

    Energy Technology Data Exchange (ETDEWEB)

    Snell, Edward H [Biophysics Group, NASA Marshall Space Flight Center, Code XD42, Huntsville, AL 35812 (United States); Helliwell, John R [Department of Chemistry, The University of Manchester, Manchester, M13 9PL (United Kingdom)

    2005-04-01

    Density difference fluid flows and sedimentation of growing crystals are greatly reduced when crystallization takes place in a reduced gravity environment. In the case of macromolecular crystallography a crystal of a biological macromolecule is used for diffraction experiments (x-ray or neutron) so as to determine the three-dimensional structure of the macromolecule. The better the internal order of the crystal then the greater the molecular structure detail that can be extracted. It is this structural information that enables an understanding of how the molecule functions. This knowledge is changing the biological and chemical sciences, with major potential in understanding disease pathologies. In this review, we examine the use of microgravity as an environment to grow macromolecular crystals. We describe the crystallization procedures used on the ground, how the resulting crystals are studied and the knowledge obtained from those crystals. We address the features desired in an ordered crystal and the techniques used to evaluate those features in detail. We then introduce the microgravity environment, the techniques to access that environment and the theory and evidence behind the use of microgravity for crystallization experiments. We describe how ground-based laboratory techniques have been adapted to microgravity flights and look at some of the methods used to analyse the resulting data. Several case studies illustrate the physical crystal quality improvements and the macromolecular structural advances. Finally, limitations and alternatives to microgravity and future directions for this research are covered. Macromolecular structural crystallography in general is a remarkable field where physics, biology, chemistry and mathematics meet to enable insight to the fundamentals of life. As the reader will see, there is a great deal of physics involved when the microgravity environment is applied to crystallization, some of it known, and undoubtedly much yet to

  4. Realization of hydrodynamic experiments on quasi-2D liquid crystal films in microgravity

    Science.gov (United States)

    Clark, Noel A.; Eremin, Alexey; Glaser, Matthew A.; Hall, Nancy; Harth, Kirsten; Klopp, Christoph; Maclennan, Joseph E.; Park, Cheol S.; Stannarius, Ralf; Tin, Padetha; Thurmes, William N.; Trittel, Torsten

    2017-08-01

    Freely suspended films of smectic liquid crystals are unique examples of quasi two-dimensional fluids. Mechanically stable and with quantized thickness of the order of only a few molecular layers, smectic films are ideal systems for studying fundamental fluid physics, such as collective molecular ordering, defect and fluctuation phenomena, hydrodynamics, and nonequilibrium behavior in two dimensions (2D), including serving as models of complex biological membranes. Smectic films can be drawn across openings in planar supports resulting in thin, meniscus-bounded membranes, and can also be prepared as bubbles, either supported on an inflation tube or floating freely. The quantized layering renders smectic films uniquely useful in 2D fluid physics. The OASIS team has pursued a variety of ground-based and microgravity applications of thin liquid crystal films to fluid structure and hydrodynamic problems in 2D and quasi-2D systems. Parabolic flights and sounding rocket experiments were carried out in order to explore the shape evolution of free floating smectic bubbles, and to probe Marangoni effects in flat films. The dynamics of emulsions of smectic islands (thicker regions on thin background films) and of microdroplet inclusions in spherical films, as well as thermocapillary effects, were studied over extended periods within the OASIS (Observation and Analysis of Smectic Islands in Space) project on the International Space Station. We summarize the technical details of the OASIS hardware and give preliminary examples of key observations.

  5. Rapid crystallization during recycling of basaltic andesite tephra: timescales determined by reheating experiments.

    Science.gov (United States)

    Deardorff, Nicholas; Cashman, Katharine

    2017-04-12

    Microcrystalline inclusions within microlite-poor matrix are surprisingly common in low intensity eruptions around the world, yet their origin is poorly understood. Inclusions are commonly interpreted as evidence of crystallization along conduit margins. Alternatively, these clasts may be recycled from low level eruptions where they recrystallize by heating within the vent. We conducted a series of experiments heating basaltic andesite lapilli from temperatures below the glass transition (~690 °C) to above inferred eruption temperatures (>1150 °C) for durations of 2 to >60 minutes. At 690 °C  800 °C, crystallization occurs in active submarine volcano NW Rota-1, Mariana arc and subaerial volcano Stromboli suggest that characteristic signatures of clast recycling are different in the two environments. Specifically, chlorine assimilation provides key evidence of recycling in submarine samples, while bands of oxides bordering microcrystalline inclusions are unique to subaerial environments. Correct identification of recycling at basaltic vents will improve (lower) estimates of mass eruption rate and help to refine interpretations of eruption dynamics.

  6. Applying shot boundary detection for automated crystal growth analysis during in situ transmission electron microscope experiments

    Energy Technology Data Exchange (ETDEWEB)

    Moeglein, W. A.; Griswold, R.; Mehdi, B. L.; Browning, N. D.; Teuton, J.

    2017-01-03

    In-situ (scanning) transmission electron microscopy (S/TEM) is being developed for numerous applications in the study of nucleation and growth under electrochemical driving forces. For this type of experiment, one of the key parameters is to identify when nucleation initiates. Typically the process of identifying the moment that crystals begin to form is a manual process requiring the user to perform an observation and respond accordingly (adjust focus, magnification, translate the stage etc.). However, as the speed of the cameras being used to perform these observations increases, the ability of a user to “catch” the important initial stage of nucleation decreases (there is more information that is available in the first few milliseconds of the process). Here we show that video shot boundary detection (SBD) can automatically detect frames where a change in the image occurs. We show that this method can be applied to quickly and accurately identify points of change during crystal growth. This technique allows for automated segmentation of a digital stream for further analysis and the assignment of arbitrary time stamps for the initiation of processes that are independent of the user’s ability to observe and react.

  7. Single ice crystal measurements during nucleation experiments with the depolarization detector IODE

    Directory of Open Access Journals (Sweden)

    M. Nicolet

    2008-12-01

    Full Text Available In order to determine the efficiency of aerosol particles of several types to nucleate ice, an Ice Optical DEpolarization detector (IODE was developed to distinguish between water droplets and ice crystals in ice nucleation chambers. A laser beam polarized linearly (power: 50 mW, wavelength: 407 nm is directed through the chamber. The scattered light intensity from particles is measured at a scattering angle of Θ=175° in both polarization components (parallel and perpendicular. The ratio between the perpendicular intensity over the total one gives the depolarization ratio δ. Single particle detection is possible, using a peak detection algorithm. For high particle concentrations, a real-time signal averaging method can also be run simultaneously. The IODE detector was used in connection with the Zurich ice nucleation chamber during the ICIS 2007 workshop where ice nucleation experiments were performed with several aerosol types. In presence of ice crystals, peaks were detected in both channels, generating depolarization signals. Mean values of δ ranged from 0.24 to 0.37.

  8. Single ice crystal measurements during nucleation experiments with the depolarization detector IODE

    Directory of Open Access Journals (Sweden)

    M. Nicolet

    2010-01-01

    Full Text Available In order to determine the efficiency of different aerosol particles to nucleate ice, an Ice Optical DEpolarization detector (IODE was developed to distinguish between water droplets and ice crystals in ice nucleation chambers. A laser beam polarized linearly (power: 50 mW, wavelength: 407 nm is directed through the chamber. The scattered light intensity from particles is measured at a scattering angle of Θ=175° in both polarization components (parallel and perpendicular. The ratio between the perpendicular intensity over the total one yields the depolarization ratio δ. Single particle detection is possible, using a peak detection algorithm. For high particle concentrations, a real-time signal averaging method can also be run simultaneously.

    The IODE detector was used in connection with the Zurich ice nucleation chamber during the ICIS 2007 workshop where ice nucleation experiments were performed with several aerosol types. In presence of ice crystals, a depolarization ratio could be measured on a particle-by-particle basis. Mean values of δ ranged from 0.24 to 0.37 and agree well with theoretical calculations.

  9. Single ice crystal measurements during nucleation experiments with the depolarization detector IODE

    Science.gov (United States)

    Nicolet, M.; Stetzer, O.; Lüönd, F.; Möhler, O.; Lohmann, U.

    2010-01-01

    In order to determine the efficiency of different aerosol particles to nucleate ice, an Ice Optical DEpolarization detector (IODE) was developed to distinguish between water droplets and ice crystals in ice nucleation chambers. A laser beam polarized linearly (power: 50 mW, wavelength: 407 nm) is directed through the chamber. The scattered light intensity from particles is measured at a scattering angle of Θ=175° in both polarization components (parallel and perpendicular). The ratio between the perpendicular intensity over the total one yields the depolarization ratio δ. Single particle detection is possible, using a peak detection algorithm. For high particle concentrations, a real-time signal averaging method can also be run simultaneously. The IODE detector was used in connection with the Zurich ice nucleation chamber during the ICIS 2007 workshop where ice nucleation experiments were performed with several aerosol types. In presence of ice crystals, a depolarization ratio could be measured on a particle-by-particle basis. Mean values of δ ranged from 0.24 to 0.37 and agree well with theoretical calculations.

  10. Baryon Spectroscopy - Recent results from the Crystal Barrel Experiment at ELSA -*

    Directory of Open Access Journals (Sweden)

    Schmidt C.

    2010-04-01

    Full Text Available To understand the spectrum and the properties of baryon resonances, the CBELSA/TAPS experiment investigates the photoproduction off the nucleon using linearly, circularly polarized or unpolarized photons impinging on a polarized or unpolarized target. Preliminary results on first double polarization observables have been obtained for the reactions $vec{gamma}{p}$ → pπ0 and $vec{gamma}{p}$ → pη using both circular and linear polarized photons on a longitudinally polarized target. This data will finally provide important information for the partial wave analyzes used to extract the resonances from the data.

  11. Magnification of photonic crystal fluorescence enhancement via TM resonance excitation and TE resonance extraction on a dielectric nanorod surface

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Hsin-Yu; Cunningham, Brian T [Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, 1406 W Green Street, Urbana, IL 61801 (United States); Zhang Wei [Department of Material Science and Engineering, University of Illinois at Urbana-Champaign, 1304 W Green Street, Urbana, IL 61801 (United States); Mathias, Patrick C, E-mail: bcunning@illinois.edu [Department of Bioengineering, University of Illinois at Urbana-Champaign, 1304 W Springfield Avenue, Urbana, IL 61801 (United States)

    2010-03-26

    Using a one-dimensional grating surface photonic crystal (PC), we experimentally demonstrate that the detection of fluorescent molecules on a PC surface can be substantially magnified through the combined effects of resonance-enhanced excitation of the fluorescent dye, resonance-enhanced extraction of the fluorescence emission and a dielectric nanorod surface coating increasing the surface area available for fluorophore-PC interaction. Enhanced excitation is obtained by engineering a high-Q TM resonant mode to efficiently couple with an incident TM-polarized {lambda} = 633 nm laser for exciting Cyanine-5 (Cy5). Enhanced extraction results from a low-Q TE resonance designed to spectrally overlap the Cy5 emission spectrum for channeling TE-polarized emission towards the detection instrument. The entire PC surface is coated with a porous film of TiO{sub 2} nanorods that allows more fluorophores to penetrate into the region of enhanced near-electric fields. Experimental results reveal a 588-fold enhancement in fluorescence intensity relative to an unpatterned glass surface.

  12. Flight Experiments of Physical Vapor Transport of ZnSe: Growth of Crystals in Various Convective Conditions

    Science.gov (United States)

    Su, Ching-Hua

    2015-01-01

    A low gravity material experiment will be performed in the Material Science Research Rack (MSRR) on International Space Station (ISS). The flight experiment will conduct crystal growths of ZnSe and related ternary compounds, such as ZnSeS and ZnSeTe, by physical vapor transport (PVT). The main objective of the project is to determine the relative contributions of gravity-driven fluid flows to the compositional distribution, incorporation of impurities and defects, and deviation from stoichiometry observed in the grown crystals as results of buoyancy-driven convection and growth interface fluctuations caused by irregular fluid-flows on Earth. The investigation consists of extensive ground-based experimental and theoretical research efforts and concurrent flight experimentation. The objectives of the ground-based studies are (1) obtain the experimental data and conduct the analyses required to define the optimum growth parameters for the flight experiments, (2) perfect various characterization techniques to establish the standard procedure for material characterization, (3) quantitatively establish the characteristics of the crystals grown on Earth as a basis for subsequent comparative evaluations of the crystals grown in a low-gravity environment and (4) develop theoretical and analytical methods required for such evaluations. ZnSe and related ternary compounds have been grown by vapor transport technique with real time in-situ non-invasive monitoring techniques. The grown crystals have been characterized extensively by various techniques to correlate the grown crystal properties with the growth conditions. This talk will focus on the ground-based studies on the PVT crystal growth of ZnSe and related ternary compounds, especially the effects of different growth orientations related to gravity direction on the grown crystals.

  13. Demonstration of simultaneous experiments using thin crystal multiplexing at the Linac Coherent Light Source.

    Science.gov (United States)

    Feng, Y; Alonso-Mori, R; Barends, T R M; Blank, V D; Botha, S; Chollet, M; Damiani, D S; Doak, R B; Glownia, J M; Koglin, J M; Lemke, H T; Messerschmidt, M; Nass, K; Nelson, S; Schlichting, I; Shoeman, R L; Shvyd'ko, Yu V; Sikorski, M; Song, S; Stoupin, S; Terentyev, S; Williams, G J; Zhu, D; Robert, A; Boutet, S

    2015-05-01

    Multiplexing of the Linac Coherent Light Source beam was demonstrated for hard X-rays by spectral division using a near-perfect diamond thin-crystal monochromator operating in the Bragg geometry. The wavefront and coherence properties of both the reflected and transmitted beams were well preserved, thus allowing simultaneous measurements at two separate instruments. In this report, the structure determination of a prototypical protein was performed using serial femtosecond crystallography simultaneously with a femtosecond time-resolved XANES studies of photoexcited spin transition dynamics in an iron spin-crossover system. The results of both experiments using the multiplexed beams are similar to those obtained separately, using a dedicated beam, with no significant differences in quality.

  14. A methodology to determine boundary conditions from forced convection experiments using liquid crystal thermography

    Science.gov (United States)

    Jakkareddy, Pradeep S.; Balaji, C.

    2017-02-01

    This paper reports the results of an experimental study to estimate the heat flux and convective heat transfer coefficient using liquid crystal thermography and Bayesian inference in a heat generating sphere, enclosed in a cubical Teflon block. The geometry considered for the experiments comprises a heater inserted in a hollow hemispherical aluminium ball, resulting in a volumetric heat generation source that is placed at the center of the Teflon block. Calibrated thermochromic liquid crystal sheets are used to capture the temperature distribution at the front face of the Teflon block. The forward model is the three dimensional conduction equation which is solved within the Teflon block to obtain steady state temperatures, using COMSOL. Match up experiments are carried out for various velocities by minimizing the residual between TLC and simulated temperatures for every assumed loss coefficient, to obtain a correlation of average Nusselt number against Reynolds number. This is used for prescribing the boundary condition for the solution to the forward model. A surrogate model obtained by artificial neural network built upon the data from COMSOL simulations is used to drive a Markov Chain Monte Carlo based Metropolis Hastings algorithm to generate the samples. Bayesian inference is adopted to solve the inverse problem for determination of heat flux and heat transfer coefficient from the measured temperature field. Point estimates of the posterior like the mean, maximum a posteriori and standard deviation of the retrieved heat flux and convective heat transfer coefficient are reported. Additionally the effect of number of samples on the performance of the estimation process has been investigated.

  15. A methodology to determine boundary conditions from forced convection experiments using liquid crystal thermography

    Science.gov (United States)

    Jakkareddy, Pradeep S.; Balaji, C.

    2016-05-01

    This paper reports the results of an experimental study to estimate the heat flux and convective heat transfer coefficient using liquid crystal thermography and Bayesian inference in a heat generating sphere, enclosed in a cubical Teflon block. The geometry considered for the experiments comprises a heater inserted in a hollow hemispherical aluminium ball, resulting in a volumetric heat generation source that is placed at the center of the Teflon block. Calibrated thermochromic liquid crystal sheets are used to capture the temperature distribution at the front face of the Teflon block. The forward model is the three dimensional conduction equation which is solved within the Teflon block to obtain steady state temperatures, using COMSOL. Match up experiments are carried out for various velocities by minimizing the residual between TLC and simulated temperatures for every assumed loss coefficient, to obtain a correlation of average Nusselt number against Reynolds number. This is used for prescribing the boundary condition for the solution to the forward model. A surrogate model obtained by artificial neural network built upon the data from COMSOL simulations is used to drive a Markov Chain Monte Carlo based Metropolis Hastings algorithm to generate the samples. Bayesian inference is adopted to solve the inverse problem for determination of heat flux and heat transfer coefficient from the measured temperature field. Point estimates of the posterior like the mean, maximum a posteriori and standard deviation of the retrieved heat flux and convective heat transfer coefficient are reported. Additionally the effect of number of samples on the performance of the estimation process has been investigated.

  16. Use of crystal methamphetamine among male adolescents in Cape Town, South Africa: Caregivers' experiences.

    Science.gov (United States)

    Asante, Kwaku Oppong; Lentoor, Antonio G

    2017-03-27

    Against the background that crystal methamphetamine (colloquially known as "tik") is extensively used by the emerging working class Coloured youth in Cape Town, South Africa, this exploratory qualitative study was conducted to explore the experience of mothers whose children use methamphetamine. The researchers conducted one-to-one semi-structured in-depth interviews with sixteen (16) purposively selected caregivers (mothers) whose sons use methamphetamine. Interviews were recorded and simultaneously translated and transcribed. Thematic analysis was used to identify themes related to the experiences of caregivers of youth with methamphetamine problems. Findings showed that youth misbehaviour provided a context that led to feelings of shame and embarrassment. Participants also experienced personal challenges which included emotional problems, fear and self-blame. Participants also expressed family disruptions and financial drain as adverse experiences as a results of their sons' misbehaviour. The study results highlight the psychosocial challenges for caregivers of children who use methamphetamine. These findings underscore the need for effort to be directed at the development of formal support interventions for mothers of youth who are troubled with addiction.

  17. Experiments and PIC simulations on liquid crystal plasma mirrors for pulse contrast enhancement

    Science.gov (United States)

    Cochran, G. E.; Poole, P. L.; Krygier, A.; Foster, P. S.; Scott, G. G.; Wilson, L. A.; Bailey, J.; Bourgeois, N.; Hernandez-Gomez, C.; Heery, R.; Purcell, J.; Neely, D.; Rajeev, P. P.; Freeman, R. R.; Schumacher, D. W.

    2016-10-01

    High pulse contrast is crucial for performing many experiments on high intensity lasers in order to minimize modification of the target surface by pre-pulse. This is often achieved through the use of solid dielectric plasma mirrors which can limit laser shot rates. Liquid crystal films, originally developed as variable thickness ion acceleration targets, have been demonstrated as effective plasma mirrors for pulse cleaning, reaching peak reflectivities over 70%. These films were used as plasma mirrors in an ion acceleration experiment on the Scarlet laser and the resultant increase in peak proton energy and change in acceleration direction will be discussed. Also presented here are novel 2D3V, LSP particle-in-cell simulations of dielectric plasma mirror operation. By including multiphoton ionization and dimensionality corrections, an excellent match to experiment is obtained over 4 decades in intensity. Analysis of pulse shortening and plasma critical surface behavior in these simulations will be discussed. Formation of thin films at 1.5 Hz will also be presented. Performed with support from the DARPA PULSE program through AMRDEC, from NNSA, and from OSC.

  18. Influence of the Siberian larch extract on the processes of peroxide oxidation of lipids in experiment

    Directory of Open Access Journals (Sweden)

    Pateyuk Andrey

    2016-03-01

    Full Text Available In modern conditions wood processing is one of the primary branches of production in Transbaikal region. In connection with big squares of logging the question of processing and utilizing waste products directly on the spot is particularly acute. We researched the activity of water extract from sawdust of Siberian larch "Ekstrapinus" on the power exchange and processes of peroxide oxidation of lipids against immobilized stress in experiment. The data provided in the article prove that the use of Ekstrapinus extract reduces the pathological violations arising under stress. So, Ekstrapinus extract restores energy potential of cages when modeling stress, restores energy potential of cells, normalizes balance in the system "peroxide oxidation of lipids – antioxidant protection" and supports the balance of tiol in an animal organism in the state of stress. Considering absence of toxicity in the recommended doses, it is possible to recommend their application under stress.

  19. Dynamic crystallization experiments bearing on the origin of textures in impact-generated liquids. [for lunar rock formation

    Science.gov (United States)

    Lofgren, G. E.

    1977-01-01

    Dynamic crystallization experiments on a synthetic glass of 14310 composition show that the density and distribution of crystals present at the initiation of cooling can drastically affect the texture of the crystallized product. Experiments were performed in one-atmosphere gas-mixing furnaces at an oxygen fugacity slightly below iron-wustite, and precooling crystallization, cooling history, and melt history were systematically varied. When cooled from a complete liquid, the experimental charges were porphyritic with 1-2 mm phenocrysts set in a very fine-grained matrix (less than 0.1 mm). This result suggests that 14310 did not cool from a complete melt. When cooled from a crystal-liquid mixture, the experimental charges had widely varying textures depending on the density and distribution of crystals that act as nucleation sites. It is suggested that the close spatial association of widely divergent textures in the matrices of some breccias and rocks might arise in this manner; local variations in cooling rates are not required.

  20. EXTRACT

    DEFF Research Database (Denmark)

    Pafilis, Evangelos; Buttigieg, Pier Luigi; Ferrell, Barbra

    2016-01-01

    The microbial and molecular ecology research communities have made substantial progress on developing standards for annotating samples with environment metadata. However, sample manual annotation is a highly labor intensive process and requires familiarity with the terminologies used. We have the...... and text-mining-assisted curation revealed that EXTRACT speeds up annotation by 15-25% and helps curators to detect terms that would otherwise have been missed.Database URL: https://extract.hcmr.gr/....

  1. Optimal cuts to extract the third-order piezoelectric constants and electrostictive constants of langasite single crystals through the electroelastic effect.

    Science.gov (United States)

    Zhang, Haifeng

    2013-07-01

    Optimal cuts to determine the third-order piezoelectric constants and electrostrictive constants of langasite single crystals by the resonator method are proposed. By selecting several langasite resonators with optimal cut angles and measuring their electroelastic effects, third-order piezoelectric constants and electrostrictive constants of langasite single crystals may be extracted. The numerical method to search these optimal cut angles is presented. The methodology has been validated by finite element analysis. This method will simplify traditional methods used to determine the third-order piezoelectric and electrostrictive constants for langasite single crystals and could potentially produce more accurate results. The method could also be used to determine the third-order piezoelectric and electrostrictive constants for other crystals with trigonal 32 symmetry.

  2. First experiences with semi-autonomous robotic harvesting of protein crystals.

    Science.gov (United States)

    Viola, Robert; Walsh, Jace; Melka, Alex; Womack, Wesley; Murphy, Sean; Riboldi-Tunnicliffe, Alan; Rupp, Bernhard

    2011-07-01

    The demonstration unit of the Universal Micromanipulation Robot (UMR) capable of semi-autonomous protein crystal harvesting has been tested and evaluated by independent users. We report the status and capabilities of the present unit scheduled for deployment in a high-throughput protein crystallization center. We discuss operational aspects as well as novel features such as micro-crystal handling and drip-cryoprotection, and we extrapolate towards the design of a fully autonomous, integrated system capable of reliable crystal harvesting. The positive to enthusiastic feedback from the participants in an evaluation workshop indicates that genuine demand exists and the effort and resources to develop autonomous protein crystal harvesting robotics are justified.

  3. X-ray Imaging of MagLIF Experiments Using a Spherically-Bent Crystal Optic

    Science.gov (United States)

    Harding, E. C.; Gomez, M. R.; Jennings, C. A.; Knapp, P. F.; Slutz, S. A.; Sefkow, A. B.; Awe, T. J.; Hansen, S. B.; Peterson, K. J.; Hahn, K. D.; McBride, R. D.; Rochau, G. A.; Sinars, D. B.; Golovkin, I.

    2015-11-01

    The recent Magnetized Liner Inertial Fusion (MagLIF) experiments performed on Sandia's Z-machine produced significant thermonuclear DD fusion yields that were accompanied by observable x-ray emission [M.R. Gomez et. al., PRL (2014)]. The MagLIF experiments relied on a spherically-bent crystal optic to image portions of the x-ray continuum that were generated by the hot stagnation plasma. The images of stagnation show a long (6 to 8 mm) and narrow (~100 micron) column of x-ray emission with structure in both directions. This structure may be caused by variations in the electron temperature (Te) and density (ne) , as well as opacity variations in the surrounding Be pusher. Here we investigate the possible contributions from each of these effects. We will also discuss the development of a diagnostic technique in which Te and ne of the DD fuel are inferred from spectra emitted by Fe impurities that become ionized to a He-like charge state. Sandia National Labs is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. DoE NNSA under contract DE-AC04-94AL85000.

  4. The effect of tailor-made additives on crystal growth of methyl paraben: Experiments and modelling

    Science.gov (United States)

    Cai, Zhihui; Liu, Yong; Song, Yang; Guan, Guoqiang; Jiang, Yanbin

    2017-03-01

    In this study, methyl paraben (MP) was selected as the model component, and acetaminophen (APAP), p-methyl acetanilide (PMAA) and acetanilide (ACET), which share the similar molecular structure as MP, were selected as the three tailor-made additives to study the effect of tailor-made additives on the crystal growth of MP. HPLC results indicated that the MP crystals induced by the three additives contained MP only. Photographs of the single crystals prepared indicated that the morphology of the MP crystals was greatly changed by the additives, but PXRD and single crystal diffraction results illustrated that the MP crystals were the same polymorph only with different crystal habits, and no new crystal form was found compared with other references. To investigate the effect of the additives on the crystal growth, the interaction between additives and facets was discussed in detail using the DFT methods and MD simulations. The results showed that APAP, PMAA and ACET would be selectively adsorbed on the growth surfaces of the crystal facets, which induced the change in MP crystal habits.

  5. Monitoring and scoring counter-diffusion protein crystallization experiments in capillaries by in situ dynamic light scattering.

    Directory of Open Access Journals (Sweden)

    Dominik Oberthuer

    Full Text Available In this paper, we demonstrate the feasibility of using in situ Dynamic Light Scattering (DLS to monitor counter-diffusion crystallization experiments in capillaries. Firstly, we have validated the quality of the DLS signal in thin capillaries, which is comparable to that obtained in standard quartz cuvettes. Then, we have carried out DLS measurements of a counter-diffusion crystallization experiment of glucose isomerase in capillaries of different diameters (0.1, 0.2 and 0.3 mm in order to follow the temporal evolution of protein supersaturation. Finally, we have compared DLS data with optical recordings of the progression of the crystallization front and with a simulation model of counter-diffusion in 1D.

  6. Monitoring and scoring counter-diffusion protein crystallization experiments in capillaries by in situ dynamic light scattering.

    Science.gov (United States)

    Oberthuer, Dominik; Melero-García, Emilio; Dierks, Karsten; Meyer, Arne; Betzel, Christian; Garcia-Caballero, Alfonso; Gavira, Jose A

    2012-01-01

    In this paper, we demonstrate the feasibility of using in situ Dynamic Light Scattering (DLS) to monitor counter-diffusion crystallization experiments in capillaries. Firstly, we have validated the quality of the DLS signal in thin capillaries, which is comparable to that obtained in standard quartz cuvettes. Then, we have carried out DLS measurements of a counter-diffusion crystallization experiment of glucose isomerase in capillaries of different diameters (0.1, 0.2 and 0.3 mm) in order to follow the temporal evolution of protein supersaturation. Finally, we have compared DLS data with optical recordings of the progression of the crystallization front and with a simulation model of counter-diffusion in 1D.

  7. The Role of Geometrically Necessary Dislocations in Cantilever Beam Bending Experiments of Single Crystals

    Directory of Open Access Journals (Sweden)

    Edgar Husser

    2017-03-01

    Full Text Available The mechanical behavior of single crystalline, micro-sized copper is investigated in the context of cantilever beam bending experiments. Particular focus is on the role of geometrically necessary dislocations (GNDs during bending-dominated load conditions and their impact on the characteristic bending size effect. Three different sample sizes are considered in this work with main variation in thickness. A gradient extended crystal plasticity model is presented and applied in a three-dimensional finite-element (FE framework considering slip system-based edge and screw components of the dislocation density vector. The underlying mathematical model contains non-standard evolution equations for GNDs, crystal-specific interaction relations, and higher-order boundary conditions. Moreover, two element formulations are examined and compared with respect to size-independent as well as size-dependent bending behavior. The first formulation is based on a linear interpolation of the displacement and the GND density field together with a full integration scheme whereas the second is based on a mixed interpolation scheme. While the GND density fields are treated equivalently, the displacement field is interpolated quadratically in combination with a reduced integration scheme. Computational results indicate that GND storage in small cantilever beams strongly influences the evolution of statistically stored dislocations (SSDs and, hence, the distribution of the total dislocation density. As a particular example, the mechanical bending behavior in the case of a physically motivated limitation of GND storage is studied. The resulting impact on the mechanical bending response as well as on the predicted size effect is analyzed. Obtained results are discussed and related to experimental findings from the literature.

  8. Phyto-crystallization of palladium through reduction process using Cinnamom zeylanicum bark extract

    Energy Technology Data Exchange (ETDEWEB)

    Sathishkumar, M.; Sneha, K.; Kwak, In Seob; Mao, Juan [Environmental Biotechnology National Research Laboratory, School of Chemical Engineering, Research Institute of Industrial Technology, Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Tripathy, S.J. [Nanoparticulate Materials Laboratory, Division of Advanced Materials Engineering, Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Yun, Y.-S., E-mail: ysyun@chonbuk.ac.kr [Environmental Biotechnology National Research Laboratory, School of Chemical Engineering, Research Institute of Industrial Technology, Chonbuk National University, Jeonju 561-756 (Korea, Republic of)

    2009-11-15

    In this paper we studied the potential of nanocrystalline palladium particle production using Cinnamom zeylanicum bark extract (CBE) as the biomaterial for the first time. We studied the effects of biomaterial dosage, pH and temperature on nanoparticle formation; none of these factors had a major effect on the size and shape of the nanoparticles formed. Transmission electron microscopy (TEM) observations confirmed the synthesis of nano-sized palladium particles. More or less uniformly sized palladium nanoparticles were synthesized with an average size ranging from 15 to 20 nm. It was found that the zeta potential of these formed palladium nanoparticles was negative, and that it increased with an increase in pH. Energy dispersive X-ray (EDX) analysis results confirmed the significant presence of palladium. Of the palladium ions, 60% were reduced to a zero valent form by CBE. Terpenoids are believed to play an important role in palladium nanoparticle biosynthesis through the reduction of palladium ions. Currently, however, the exact mechanism for the synthesis of palladium nanoparticles is unclear. Our protocol for the phyto-synthesis of palladium nanoparticles under moderate pH and room temperature offers a new means to develop environmentally benign nanoparticles.

  9. Rheology of crystal-bearing natural magmas: Torsional deformation experiments at 800 °C and 100 MPa

    Science.gov (United States)

    Okumura, Satoshi; Kushnir, Alexandra R. L.; Martel, Caroline; Champallier, Rémi; Thibault, Quentin; Takeuchi, Shingo

    2016-12-01

    Rheological behavior of crystal-bearing magma is a controlling factor of magma flow dynamics and hence the style of volcanic eruptions. In this study, we performed torsional deformation experiments to determine the viscosity of crystal-bearing rhyolitic and dacitic magmas. The experiments were conducted at a temperature of 800 °C and under confining and pore fluid pressures of 100 and 80 MPa, respectively, by using an internally heated gas-medium deformation apparatus. To simulate the rheology of natural magma, we deformed volcanic rocks with 16 and 45 vol% crystallinities and gas bubbles. These rocks have different crystal and bubble shape and size, which appear to influence magma rheology. By using the mechanical data obtained, we calculated flow indices and viscosities for these magmas. For magma with 16 vol% crystallinity, the flow index showed good agreement with previous data obtained from experiments on synthetic magma analogues and model predictions. In contrast, the flow index was smaller than those obtained from previous experiments and model predictions at 45 vol% crystallinity, which may be explained by considering that natural magma contains crystals with different shapes and sizes. We also found that the apparent viscosity of the magma increased when sample-scale fractures were observed in run products. This means that the heterogeneity of natural magma causes locally stiff regions within the sample owing to crystal interaction. Our data indicate that the viscosity of crystal-rich magma is strongly dependent on the strain rate. This implies that magma ascending in a volcanic conduit shows a plug-type flow because the viscosity decreases near the conduit rim where the strain rate is high. Additionally, if shear localises near the rim, a currently unrecognised mechanism may contribute to outgassing from the central portion of the conduit because outgassing is difficult to facilitate without shear deformation.

  10. Development of CaMoO4 crystal scintillators for double beta decay experiment with 100-Mo

    CERN Document Server

    Annenkov, A N; Danevich, F A; Georgadze, A S; Kim, S K; Kim, H J; Kim, Y D; Kobychev, V V; Kornoukhov, V N; Korzhik, M; Lee, J I; Missevitch, O; Mokina, V M; Nagorny, S S; Nikolaiko, A S; Poda, D V; Podviyanuk, R B; Sedlak, D J; Shkulkova, O G; So, J H; Solsky, I M; Tretyak, V I; Yurchenko, S S

    2007-01-01

    Energy resolution, alpha/beta ratio, pulse-shape discrimination for gamma rays and alpha particles, temperature dependence of scintillation properties, and radioactive contamination were studied with CaMoO4 crystal scintillators. A high sensitivity experiment to search for neutrinoless double beta decay of 100-Mo by using CaMoO4 scintillators is discussed.

  11. Extractive industries and sustainable development: an evaluation of World Bank Group experience

    Energy Technology Data Exchange (ETDEWEB)

    Andres Liebenthal; Roland Michelitsch; Ethel Tarazona

    2005-07-01

    How effectively has the World Bank Group assisted its clients in enhancing the contribution of the extractive industries to sustainable development? (Extractive industries include oil, gas, and mining of minerals including coals and metals.) This evaluation finds that with its global mandate and experience, comprehensive country development focus, and overarching mission to fight poverty, the World Bank Group is well positioned to help countries overcome the policy, institutional, and technical challenges that prevent them from transforming resource endowments into sustainable benefits. Furthermore, the World Bank Group's achievements are many. On the whole, its extractive industries projects have produced positive economic and financial results, though compliance with its environmental and social safeguards remains a challenge. Its research has broadened and deepened understanding of the causes for the disappointing performance of resource-rich countries. Its guidelines for the mitigation of adverse environmental and social impacts have been widely used and appreciated. More recently, it has begun to address the challenge of country governance with a variety of instruments. The World Bank Group can, however, do much to improve its performance in enhancing the extractive industry sector's contribution to sustainable development and poverty reduction. The report identifies three main areas for improvement - formulating an integrated strategy, strengthening implementation and engagement of stakeholders. 5 annexes.

  12. Ground based experiments on the growth and characterization of L-Arginine Phosphate (LAP) crystals

    Science.gov (United States)

    Rao, S. M.; Cao, C.; Batra, A. K.; Lal, R. B.; Mookherji, T. K.

    1991-01-01

    L-Arginine Phosphate (LAP) is a new nonlinear optical material with higher efficiency for harmonic generation compared to KDP. Crystals of LAP were grown in the laboratory from supersaturated solutions by temperature lowering technique. Investigations revealed the presence of large dislocation densities inside the crystals which are observed to produce refractive index changes causing damage at high laser powers. This is a result of the convection during crystal growth from supersaturated solutions. It is proposed to grow these crystals in a diffusion controlled growth condition under microgravity environment and compare the crystals grown in space with those grown on ground. Physical properties of the solutions needed for modelling of crystal growth are also presented.

  13. Aerosol hygroscopicity and cloud droplet activation of extracts of filters from biomass burning experiments

    Science.gov (United States)

    Carrico, Christian M.; Petters, Markus D.; Kreidenweis, Sonia M.; Collett, Jeffrey L.; Engling, Guenter; Malm, William C.

    2008-04-01

    In this laboratory closure study, we compare sub- and supersaturated water uptake properties for aerosol particles possessing a range of hygroscopicity. Measurements for water sub-saturated conditions used a hygroscopic tandem differential mobility analyzer (HTDMA). Simultaneously, measurements of particle critical supersaturation were conducted on the same sample stream with a continuous flow cloud condensation nuclei (CCN) counter. For these experiments, we used filter-collected samples of biomass smoke generated in the combustion of two common wildland fire fuels, western sagebrush and Alaskan duff core. Extractions of separate sections of the filter were performed using two solvents, ultrapure water and methanol. The extracts were subsequently atomized, producing aerosols having a range of hygroscopic responses. HTDMA and CCN measurements were fit to a single-parameter model of water uptake, in which the fit parameter is denoted κ, the hygroscopicity parameter. Here, for the four extracts we observed mean values of the hygroscopicity parameter of 0.06 CCN-derived values of κ for each experiment agreed within approximately 20%. Applicability of the κ-parameterization to other multicomponent aerosols relevant to the atmosphere remains to be tested.

  14. Laser-induced breakdown and damage generation by nonlinear frequency conversion in ferroelectric crystals: Experiment and theory

    Energy Technology Data Exchange (ETDEWEB)

    Louchev, Oleg A.; Saito, Norihito; Wada, Satoshi [Center for Advanced Photonics, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Hatano, Hideki; Kitamura, Kenji [National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)

    2013-11-28

    Using our experimental data for ns pulsed second harmonic generation (SHG) by periodically poled stoichiometric LiTaO{sub 3} (PPSLT) crystals, we consider in detail the mechanism underlying laser-induced damage in ferroelectric crystals. This mechanism involves generation and heating of free electrons, providing an effective kinetic pathway for electric breakdown and crystal damage in ns pulsed operation via combined two-photon absorption (TPA) and induced pyroelectric field. In particular, a temperature increase in the lattice of ≈1 K induced initially by ns SHG and TPA at the rear of operating PPSLT crystal is found to induce a gradient of spontaneous polarization generating a pyroelectric field of ≈10 kV/cm, accelerating free electrons generated by TPA to an energy of ≈10 eV, followed by impact ionization and crystal damage. Under the damage threshold for ns operation, the impact ionization does not lead to the avalanche-like increase of free electron density, in contrast to the case of shorter ps and fs pulses. However, the total number of collisions by free electrons, ≈10{sup 18} cm{sup −3} (generated during the pulse and accelerated to the energy of ≈10 eV), can produce widespread structural defects, which by entrapping electrons dramatically increase linear absorption for both harmonics in subsequent pulses, creating a positive feedback for crystal lattice heating, pyroelectric field and crystal damage. Under pulse repetition, defect generation starting from the rear of the crystal can propagate towards its center and front side producing damage tracks along the laser beam and stopping SHG. Theoretical analysis leads to numerical estimates and analytical approximation for the threshold laser fluence for onset of this damage mechanism, which agree well with our (i) experiments for the input 1064 nm radiation in 6.8 kHz pulsed SHG by PPSLT crystal, (ii) pulsed low frequency 532 nm radiation transmission experiments, and also (iii) with the data

  15. Recent progress in oxide scintillation crystals development by low-thermal gradient Czochralski technique for particle physics experiments

    Science.gov (United States)

    Shlegel, V. N.; Borovlev, Yu. A.; Grigoriev, D. N.; Grigorieva, V. D.; Danevich, F. A.; Ivannikova, N. V.; Postupaeva, A. G.; Vasiliev, Ya. V.

    2017-08-01

    Modern particle physics experiments call for high performance scintillation detectors with unique properties: radiation-resistant in high energy and astrophysics, highly radiopure, containing certain elements or enriched isotopes in astroparticle physics. The low-thermal gradient Czochralski (LTG CZ) crystal growth technique provides excellent quality large volume radiopure crystal scintillators. Absence of thermoelastic stress in the crystal and overheating of the melt in the LTG CZ method is particularly significant in production of crystalline materials with strong thermal anisotropic properties and low mechanical strength, with a very high yield of crystalline boules and low losses of initial charge, crucially important in production of crystal scintillators from enriched isotopes for double beta decay experiments. Here we discuss progress in development of the well known scintillators (Bi4Ge3O12 (BGO), CdWO4, ZnWO4, CaMoO4, PbMoO4), as well as R&D of new materials (ZnMoO4, Li2MoO4, Na2Mo2O7) for the next generation experiments in particle physics.

  16. Structured extracapsular cataract extraction-intraocular lens microsurgical training: report of a trainee's experience.

    Science.gov (United States)

    Aghaji, A E; Natchiar, G

    2011-01-01

    The aim was to report the experience an ophthalmologist gained in a structured intraocular lens (IOL) microsurgery training program for the information and benefit of colleagues in ophthalmology training institutions. An ophthalmologist was trained in extracapsular cataract extraction (ECCE)-IOL implant in Aravind Eye Hospital (AEH), Madurai, for a period of 8 weeks. Details of patients operated on, procedures observed, and conferences attended were prospectively recorded in a log book. Training was available in conventional ECCE with posterior chamber IOL (ECCE-PCIOL), small incision sutureless cataract surgery, and phacoemulsification. During the period, this trainee observed a total of 1527 cataract extractions, administered 528 retrobulbar and 1047 facial blocks, and also operated on 75 patients. The trainee gained experience and confidence to perform high-quality, low-cost cataract surgery. Hands-on experience and competence in quality ECCE-IOL implant microsurgery can be acquired in a short period of time in a high-volume cataract center. Trainees can also be exposed to other techniques of cataract surgery. Ophthalmology training centers with diminishing surgical training opportunities can also benefit from this structured training in a high-volume cataract center like Aravind Eye Hospital.

  17. Wall modified photonic crystal fibre capillaries as porous layer open tubular columns for in-capillary micro-extraction and capillary chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Kazarian, Artaches A. [Australian Centre for Research on Separation Science, School of Physical Sciences, University of Tasmania, Private Bag 75, Hobart, Tasmania 7001 (Australia); W.M. Keck FT-ICR-MS Laboratory, Department of Chemistry, North Carolina State University, Raleigh, NC (United States); Sanz Rodriguez, Estrella; Deverell, Jeremy A. [Australian Centre for Research on Separation Science, School of Physical Sciences, University of Tasmania, Private Bag 75, Hobart, Tasmania 7001 (Australia); McCord, James; Muddiman, David C. [W.M. Keck FT-ICR-MS Laboratory, Department of Chemistry, North Carolina State University, Raleigh, NC (United States); Paull, Brett, E-mail: Brett.Paull@utas.edu.au [Australian Centre for Research on Separation Science, School of Physical Sciences, University of Tasmania, Private Bag 75, Hobart, Tasmania 7001 (Australia); ARC Centre of Excellence for Electromaterials Science, School of Physical Sciences, University of Tasmania, Private Bag 75, Hobart, Tasmania 7001 (Australia)

    2016-01-28

    Wall modified photonic crystal fibre capillary columns for in-capillary micro-extraction and liquid chromatographic separations is presented. Columns contained 126 internal parallel 4 μm channels, each containing a wall bonded porous monolithic type polystyrene-divinylbenzene layer in open tubular column format (PLOT). Modification longitudinal homogeneity was monitored using scanning contactless conductivity detection and scanning electron microscopy. The multichannel open tubular capillary column showed channel diameter and polymer layer consistency of 4.2 ± 0.1 μm and 0.26 ± 0.02 μm respectively, and modification of 100% of the parallel channels with the monolithic polymer. The modified multi-channel capillaries were applied to the in-capillary micro-extraction of water samples. 500 μL of water samples containing single μg L{sup −1} levels of polyaromatic hydrocarbons were extracted at a flow rate of 10 μL min{sup −1}, and eluted in 50 μL of acetonitrile for analysis using HPLC with fluorescence detection. HPLC LODs were 0.08, 0.02 and 0.05 μg L{sup −1} for acenaphthene, anthracene and pyrene, respectively, with extraction recoveries of between 77 and 103%. The modified capillaries were also investigated briefly for direct application to liquid chromatographic separations, with the retention and elution of a standard protein (cytochrome c) under isocratic conditions demonstrated, proving chromatographic potential of the new column format, with run-to-run retention time reproducibility of below 1%. - Highlights: • Novel PS-DVB modified photonic crystal fibres for in-capillary micro-extraction. • New method for micro-extraction of PAHs and HPLC-FL detection at sub-ppb levels. • Demonstration of PS-DVB modified photonic crystal fibres for capillary bioseparations.

  18. Primitive SNC parent magmas and crystallization: Low PH2O experiments

    Science.gov (United States)

    Ford, D. J.; Rutherford, M. J.

    1993-01-01

    SNC meteorites are generally believed to present one of the best opportunities to study the composition and petrogenesis of Mars magmas. The crystallization ages, noble gas content, oxygen isotopic composition, and shocked minerals of the meteorites are consistent with a Martian origin. The samples range from dunite to clinopyroxenite to microgabbro. Efforts by researchers to determine parental magmas for the more primitive SNC meteorites have been complicated by crystal accumulation and possible melt segregation and removal. This has resulted in a range of parent magma estimates, although all appear to be Fe-rich and Al-poor. One major objective is to refine the Chassigny parent magma estimate by forcing olivine + clinopyroxene saturation upon the proposed melt composition. EETA 79001 magma compositions are also being investigated to determine the parent magma and the origin of the coarse-grained olivine and orthopyroxene megacrysts. Low pressure experiments with small but finite P(sub H2O) are being utilized to facilitate equilibrium, and to simulate the H2O indicated for these magmas. The presence of small (0.5-1.0 wt percent) amounts of H2O in SNC magmas appears to be required by the occurrence of hydrous minerals and textures in melts trapped by growing phenocrysts. This evidence for hydrous melts occurs in all SNC's except EETA 79001 and ALHA 77005, where the inclusion textures were obscured by shock effects. The lack of hydrous minerals or low temperature melts in the intercumulus regions of these rocks suggests that final emplacement was sufficiently close to the surface to allow degassing as the magma equilibrated with the low P atmosphere. Any H2O left in intercumulus phases would also tend to be lost during impact heating. Thus, although the bulk H2O of SNC's is very low, it is believed that this is explained by the near Mars surface emplacement of SNC magmas and by shock effects. Magmatic processes involving H2O need to be examined in order to

  19. Parametric X-ray radiation in crystals theory, experiments and applications

    CERN Document Server

    Baryshevsky, Vladimir G; Ulyanenkov, Alexander P

    2005-01-01

    This systematic and comprehensive monograph is devoted to parametric X-ray radiation (PXR). This radiation is generated by the motion of electrons inside a crystal, whereby the emitted photons are diffracted by the crystal and the radiation intensity critically depends on the parameters of the crystal structure. Nowadays PXR is the subject of numerous theoretical and experimental studies throughout the world. The first part of the book is a theoretical treatment of PXR, which includes a new approach to describe the radiation process in crystals. The second part is a survey of PXR experimental results and the possible applications of PXR as a tool for crystal structure analysis and a source of tunable X-ray radiation.

  20. GB-SAR Experiment On Deformation Extraction And System Error Analysis

    Science.gov (United States)

    Qu, Shibo; Wang, Yanping; Tan, Weixian; Hong, Wen

    2010-10-01

    Ground Based Synthetic Aperture Radar (GB-SAR) provides a new method to monitoring deformation in relative small region. In this paper, we present the GB-SAR imaging geometry and analyze the interferometric phase for the purpose of deformation monitoring. Deformation monitoring error sources are also analyzed through sensitivity equations, including frequency instability and its influence on interferometric phase and deformation extraction, incident angle and monitoring distance. At last, a deformation monitoring experiment is carry out using ASTRO (Advanced Scannable Two-dimensional Rail Observation system), a GB-SAR system constructed by Institute of Electronics Chinese Academy of Sciences (IECAS). The deformation monitoring results show good consistent with metal objects' movement.

  1. The First Experience With Space Scanning Extracted Beam On The Spin@u-70 Setup Target Possibility And Measurement Tool

    CERN Document Server

    Afonin, A G; Gres, V N; Terekhov, V I

    2004-01-01

    This paper presents the first results of experiments aimed at a provision of possibilities of the extracted beam space scanning on polarized target of the SPIN@U-70 Setup. The design and features of the special instrumentation are given.

  2. Power spectrum extraction for redshifted 21-cm epoch of reionization experiments: the LOFAR case

    CERN Document Server

    Harker, Geraint; Bernardi, Gianni; Brentjens, Michiel A; de Bruyn, A G; Ciardi, Benedetta; Jelic, Vibor; Koopmans, Leon V E; Labropoulos, Panagiotis; Mellema, Garrelt; Offringa, Andre; Pandey, V N; Pawlik, Andreas H; Schaye, Joop; Thomas, Rajat M; Yatawatta, Sarod

    2010-01-01

    One of the aims of the Low Frequency Array (LOFAR) Epoch of Reionization (EoR) project is to measure the power spectrum of variations in the intensity of redshifted 21-cm radiation from the EoR. The sensitivity with which this power spectrum can be estimated depends on the level of thermal noise and sample variance, and also on the systematic errors arising from the extraction process, in particular from the subtraction of foreground contamination. We model the extraction process using realistic simulations of the cosmological signal, the foregrounds and noise, and so estimate the sensitivity of the LOFAR EoR experiment to the redshifted 21-cm power spectrum. Detection of emission from the EoR should be possible within 360 hours of observation with a single station beam. Integrating for longer, and synthesizing multiple station beams within the primary (tile) beam, then enables us to extract progressively more accurate estimates of the power at a greater range of scales and redshifts. We discuss different obs...

  3. Continuous-wave, two-crystal, singly-resonant optical parametric oscillator: theory and experiment.

    Science.gov (United States)

    Samanta, G K; Aadhi, A; Ebrahim-Zadeh, M

    2013-04-22

    We present theoretical and experimental study of a continuous-wave, two-crystal, singly-resonant optical parametric oscillator (T-SRO) comprising two identical 30-mm-long crystals of MgO:sPPLT in a four- mirror ring cavity and pumped with two separate pump beams in the green. The idler beam after each crystal is completely out-coupled, while the signal radiation is resonant inside the cavity. Solving the coupled amplitude equations under undepleted pump approximation, we calculate the maximum threshold reduction, parametric gain acceptance bandwidth and closest possible attainable wavelength separation in arbitrary dual-wavelength generation and compare with the experimental results. Although the T-SRO has two identical crystals, the acceptance bandwidth of the device is equal to that of a single-crystal SRO. Due to the division of pump power in two crystals, the T-SRO can handle higher total pump power while lowering crystal damage risk and thermal effects. We also experimentally verify the high power performance of such scheme, providing a total output power of 6.5 W for 16.2 W of green power at 532 nm. We verified coherent energy coupling between the intra-cavity resonant signal waves resulting Raman spectral lines. Based on the T-SRO scheme, we also report a new technique to measure the temperature acceptance bandwidth of the single-pass parametric amplifier across the OPO tuning range.

  4. Benchmark of the FLUKA model of crystal channeling against the UA9-H8 experiment

    Science.gov (United States)

    Schoofs, P.; Cerutti, F.; Ferrari, A.; Smirnov, G.

    2015-07-01

    Channeling in bent crystals is increasingly considered as an option for the collimation of high-energy particle beams. The installation of crystals in the LHC has taken place during this past year and aims at demonstrating the feasibility of crystal collimation and a possible cleaning efficiency improvement. The performance of CERN collimation insertions is evaluated with the Monte Carlo code FLUKA, which is capable to simulate energy deposition in collimators as well as beam loss monitor signals. A new model of crystal channeling was developed specifically so that similar simulations can be conducted in the case of crystal-assisted collimation. In this paper, most recent results of this model are brought forward in the framework of a joint activity inside the UA9 collaboration to benchmark the different simulation tools available. The performance of crystal STF 45, produced at INFN Ferrara, was measured at the H8 beamline at CERN in 2010 and serves as the basis to the comparison. Distributions of deflected particles are shown to be in very good agreement with experimental data. Calculated dechanneling lengths and crystal performance in the transition region between amorphous regime and volume reflection are also close to the measured ones.

  5. Diminution of oxalate induced renal tubular epithelial cell injury and inhibition of calcium oxalate crystallization in vitro by aqueous extract of Tribulus terrestris

    Directory of Open Access Journals (Sweden)

    A. Aggarwal

    2010-08-01

    Full Text Available PURPOSE: Recurrence and persistent side effects of present day treatment for urolithiasis restrict their use, so an alternate solution, using phytotherapy is being sought. The present study attempted to evaluate the antilithiatic properties of Tribulus terrestris commonly called as “gokhru” which is often used in ayurveda to treat various urinary diseases including urolithiasis. MATERIALS AND METHODS: The activity of Tribulus terrestris was investigated on nucleation and the growth of the calcium oxalate (CaOx crystals as well as on oxalate induced cell injury of NRK 52E renal epithelial cells. RESULTS: Tribulus terrestris extract exhibited a concentration dependent inhibition of nucleation and the growth of CaOx crystals. When NRK-52E cells were injured by exposure to oxalate for 72 h, Tribulus terrestris extract prevented the injury in a dose-dependent manner. On treatment with the different concentrations of the plant, the cell viability increased and lactate dehydrogenase release decreased in a concentration dependent manner. CONCLUSION: The current data suggests that Tribulus terrestris extract not only has a potential to inhibit nucleation and the growth of the CaOx crystals but also has a cytoprotective role. Our results indicate that it could be a potential candidate for phytotherapy against urolithiasis.

  6. Regulation of urinary crystal inhibiting proteins and inflammatory genes by lemon peel extract and formulated citrus bioflavonoids on ethylene glycol induced urolithic rats.

    Science.gov (United States)

    Sridharan, Badrinathan; Mehra, Yogita; Ganesh, Rajesh Nachiappa; Viswanathan, Pragasam

    2016-08-01

    The objective of this study is to check the regulation of crystal matrix proteins and inflammatory mediators by citrus bioflavonoids (CB) and Lemon peel (LP) extract in hyperoxaluric rats. The animals were divided into six groups with 6 animals each. Group 1: Control, Group 2: Urolithic (Ethylene glycol (EG)-0.75%); Group 3 & 5: Preventive study (EG + CB (20 mg/kg body weight) and LP (100 mg/kg body weight) extract administration from 0th-7th week) respectively; Group 4 & 6: Curative study (EG + CB and LP extract administration from 4th-7th week) respectively by oral administration. Urinary lithogenic factors (Calcium, oxalate, phosphate and citrate) were normalized in CB & LP supplemented rats, while serum parameters revealed the nephroprotective nature of the intervening agents compared to urolithic rats (p < 0.001). Immunoblotting studies showed significantly increased expression of THP, osteopontin and transferrin in kidneys of urolithic rats (p < 0.001), while preventive and curative study showed near normal expression of these proteins. Expression of NF-κB, TNF-α and IL-6 were raised significantly (p < 0.001), while a very minimal increase in MCP-1 expression was observed in urolithic rats compared to control. Hence, supplementation of CB and LP reduced the crystal promoting factors and provides protection from crystal induced renal damage.

  7. Lead extraction with high frequency laser sheaths: a single-centre experience.

    Science.gov (United States)

    Pecha, Simon; Linder, Matthias; Gosau, Nils; Castro, Liesa; Vogler, Julia; Willems, Stephan; Reichenspurner, Hermann; Hakmi, Samer

    2017-05-01

    Extraction of chronically implanted cardiac implantable electrophysiological devices leads can be difficult. Excimer laser-assisted extraction with 40 Hz sheaths has shown good results in challenging cases. In 2012, a new 80 Hz high-frequency laser sheath became available that delivers twice as many pulses per second. Here, we report our clinical experience with the new GlideLight 80 Hz laser sheath. Between January 2012 and August 2016, 292 leads were treated in 151 patients using 80 Hz GlideLight laser sheath. Lead extraction indications included systemic infection or lead endocarditis n =  35 (23.2%), local infection n =  73 (48.3%), lead dysfunction n =  32 (21.2%), system upgrade n =  5 (3.3%), tricuspid regurgitation n =  3 (2.0%) and other indications n =  3 (2.0). All patient-related and procedural data were collected into a database and analysed. Mean patient's age was 66.2 ± 14.4 years, 73.5% were male. Ninety-one (31.2%) atrial, 159 (54.4%) ventricular and 42 (14.4%) coronary sinus leads had to be extracted. The mean time from initial lead implantation was 98.0 ± 65.2 months. Mean laser treatment time was 67.5 ± 71.3 s, mean laser pulses delivered were 5130 ± 6592. Clinical success was achieved in 99.3% of the cases, while complete procedural success was observed in 96.7%. A failure of extraction was seen in 2 (1.3%) patients. An overall complication rate of 2.0%, including two major (1.3%) and one minor (0.7%) complications, was observed. No periprocedural mortality was seen. The new GlideLight high-frequency laser sheath allows for a high safety and efficacy in extraction of chronically implanted pacemaker- and implantable cardioverter-defibrillator leads.

  8. Polypyrrole-magnetite dispersive micro-solid-phase extraction combined with ultraviolet-visible spectrophotometry for the determination of rhodamine 6G and crystal violet in textile wastewater.

    Science.gov (United States)

    Kamaruddin, Amirah Farhan; Sanagi, Mohd Marsin; Wan Ibrahim, Wan Aini; Md Shukri, Dyia S; Abdul Keyon, Aemi S

    2017-08-29

    Polypyrrole-magnetite dispersive micro-solid-phase extraction method combined with ultraviolet-visible spectrophotometry was developed for the determination of selected cationic dyes in textile wastewater. Polypyrrole-magnetite was used as adsorbent due to its thermal stability, magnetic properties, and ability to adsorb Rhodamine 6G and crystal violet. Dispersive micro-solid-phase extraction parameters were optimized, including sample pH, adsorbent amount, extraction time, and desorption solvent. The optimum polypyrrole-magnetite dispersive micro-solid phase-extraction conditions were sample pH 8, 60 mg polypyrrole-magnetite adsorbent, 5 min of extraction time, and acetonitrile as the desorption solvent. Under the optimized conditions, the polypyrrole-magnetite dispersive micro-solid-phase extraction with ultraviolet-visible method showed good linearity in the range of 0.05-7 mg/L (R(2)  > 0.9980). The method also showed a good limit of detection for the dyes (0.05 mg/L) and good analyte recoveries (97.4-111.3%) with relative standard deviations extraction and determination of dyes at trace concentration levels. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Step density waves on growing vicinal crystal surfaces - Theory and experiment

    Science.gov (United States)

    Ranguelov, Bogdan; Müller, Pierre; Metois, Jean-Jacques; Stoyanov, Stoyan

    2017-01-01

    The Burton, Cabrera and Frank (BCF) theory plays a key conceptual role in understanding and modeling the crystal growth of vicinal surfaces. In BCF theory the adatom concentration on a vicinal surface obeys to a diffusion equation, generally solved within quasi-static approximation where the adatom concentration at a given distance x from a step has a steady state value n (x) . Recently, we show that going beyond this approximation (Ranguelov and Stoyanov, 2007) [6], for fast surface diffusion and slow attachment/detachment kinetics of adatoms at the steps, a train of fast-moving steps is unstable against the formation of steps density waves. More precisely, the step density waves are generated if the step velocity exceeds a critical value related to the strength of the step-step repulsion. This theoretical treatment corresponds to the case when the time to reach a steady state concentration of adatoms on a given terrace is comparable to the time for a non-negligible change of the step configuration leading to a terrace adatom concentration n (x , t) that depends not only on the terrace width, but also on its "past width". This formation of step density waves originates from the high velocity of step motion and has nothing to do with usual kinetic instabilities of step bunching induced by Ehrlich-Schwoebel effect, surface electromigration and/or the impact of impurities on the step rate. The so-predicted formation of step density waves is illustrated by numerical integration of the equations for step motion. In order to complete our previous theoretical treatment of the non-stationary BCF problem, we perform an in-situ reflection electron microscopy experiment at specific temperature interval and direction of the heating current, in which, for the first time, the step density waves instability is evidenced on Si(111) surface during highest possible Si adatoms deposition rates.

  10. Skylab experiments. Volume 3: Materials science. [Skylab experiments on metallurgy, crystal growth, semiconductors, and combustion physics in weightless environment for high school level education

    Science.gov (United States)

    1973-01-01

    The materials science and technology investigation conducted on the Skylab vehicle are discussed. The thirteen experiments that support these investigations have been planned to evaluate the effect of a weightless environment on melting and resolidification of a variety of metals and semiconductor crystals, and on combustion of solid flammable materials. A glossary of terms which define the space activities and a bibliography of related data are presented.

  11. Bronchoscopic foreign body extraction in a pulmonary medicine department: a retrospective review of egyptian experience.

    Science.gov (United States)

    Korraa, Emad; Madkour, Ashraf; Wagieh, Khaled; Nafae, Ahmed

    2010-01-01

    Foreign body (FB) removal in our hospital was almost exclusively performed by surgeons through a rigid bronchoscope until the pulmonologists started getting involved in FB extraction. This study aimed to retrospectively review the results of 2 years of experience with 120 patients who presented or were referred to the Pulmonary Medicine Department, Ain Shams University Hospital in Cairo, Egypt, with clinical suspicion of FB aspiration during the period between December 2006 and December 2008. FBs were removed by either rigid and/or flexible bronchoscopy using either general or topical anesthesia. There were 54 male and 66 female patients with an age range between 3 months and 70 years and 68.5% of the patients were under the age of 10 years. Ninety patients (75%) presented with a definite history of FB aspiration, with a time interval between aspiration and presentation ranging between less than 6 hours and 12 months. The FB was visible on the chest x-ray in 42 cases. Aspirations were primarily into the right lung (53.2%). Seeds and scarf pins were the most common FB found, and were retrieved in 36 cases. Pulmonologists were successful in extracting 110 out of 111 (99.1%) bronchoscopically visualized FBs, and open thoracotomy was required in only 1 case for FB removal. In another 6 cases, only mucous plug was found to be the endogenous FB, whereas no FB could be found in 3 cases. No mortality or serious complications took place during or after the bronchoscopy. In conclusion, pulmonologists can extract FBs easily and safely either by using rigid and/or flexible bronchoscopes if they have the appropriate experience.

  12. Investigation of water-soluble organic matter extracted from shales during leaching experiments

    Science.gov (United States)

    Zhu, Yaling; Vieth-Hillebrand, Andrea; Wilke, Franziska D. H.; Horsfield, Brian

    2017-04-01

    The huge volumes and unknown composition of flowback and produced waters cause major public concerns about the environmental and social compatibility of hydraulic fracturing and the exploitation of gas from unconventional reservoirs. Flowback and produced waters contain not only residues of fracking additives but also chemical species that are dissolved from the shales themselves during fluid-rock interaction. Knowledge of the composition, size and structure of dissolved organic carbon (DOC) as well as the main controls on the release of DOC are a prerequisite for a better understanding of these interactions and its effects on composition of flowback and produced water. Black shales from four different geological settings and covering a maturity range Ro = 0.3-2.6% were extracted with deionized water. The DOC yields were found to decrease rapidly with increasing diagenesis and remain low throughout catagenesis. Four DOC fractions have been qualitatively and quantitatively characterized using size-exclusion chromatography. The concentrations of individual low molecular weight organic acids (LMWOA) decrease with increasing maturity of the samples except for acetate extracted from the overmature Posidonia shale, which was influenced by hydrothermal brines. The oxygen content of the shale organic matter also shows a significant influence on the release of organic acids, which is indicated by the positive trend between oxygen index (OI) and the concentrations of formate and acetate. Based on our experiments, both the properties of the organic matter source and the thermal maturation progress of the shale organic matter significantly influence the amount and quality of extracted organic compounds during the leaching experiments.

  13. Growth experiment of narrow band-gap semiconductor PbSnTe single crystals in space (M-1)

    Science.gov (United States)

    Yamada, Tomoaki

    1993-01-01

    An experiment on crystal growth of Pb(1-x)Sn(x)Te in microgravity is planned. This material is an alloy of the compound semiconductors PbTe and SnTe. It is a promising material for infrared diode lasers and detectors in the wavelength region between 6 and 30 micron. Since the electrical properties of Pb(1-x)Sn(x)Te depend greatly on the Pb/Sn ratio and crystalline defects as well as impurity concentration, homogeneous, defect-free, high-quality crystals are anticipated. Although many growth methods, such as the pulling method, the Bridgman method, the vapor growth method, etc., have been applied to the growth of Pb(1-x)Sn(x)Te, large, homogeneous, low-defect-density crystals have not yet been grown on Earth. The unsuccessful results were caused by buoyancy-driven convection in the fluids induced by the specific gravity difference between heated and cooled fluids on Earth. A crystal is grown by cooling the melt from one end of the ampoule. In crystal growth from the melt, about 30 percent of the SnTe in the melt is rejected at the solid-liquid interface during solidification. On Earth, the rejected SnTe is completely mixed with the remaining melt by convection in the melt. Therefore, SnTe concentration in the melt, and accordingly in the crystal, increases as the crystal grows. In the microgravity environment, buoyancy-driven convection is suppressed because the specific gravity difference is negligible. In that case, the rejected SnTe remains at the solid-liquid interface and its concentration increases only at the interface. If the growth rate is higher than the PbTe-SnTe interdiffusion rate, the amount of SnTe which diffuses from the interface into the melt increases as SnTe piles up at the interface, and finally it balances the amount of rejected SnTe during solidification, resulting in steady-state SnTe transportation at the interface. By using this principle, compositionally homogeneous crystals can be grown. Furthermore, low-defect-density crystals will be

  14. On the facet-skeletal transition of snow crystals - Experiments in high and low gravity

    Science.gov (United States)

    Alena, T.; Hallett, J.; Saunders, C. P. R.

    1990-01-01

    A laboratory investigation of the influence of air velocity on the growth of columnar ice crystals from the vapor over the range -3 to -5 C shows that the linear growth velocity increases and that columns transform to sheath crystals or needles as air velocity increases from a few cm/s to 40 cm/s. Comparison with a similar transition of plates to dendrites shows that, macroscopically, in both cases the facets sprout rounded tips at a critical velocity which is lower for higher ambient supersaturation. Studies in low gravity show that chamber scale convection under normal gravity may have significant influence on growth even in the absence of an imposed air velocity. Falling snow crystals become more skeletal in shape as they grow and fall with increasing velocity. This development depends critically on temperature (+ or - 0.5 C) and demonstrates that the snow crystal shape is even more dependent on environmental growth conditions that previously thought.

  15. Electronic properties of single crystal CVD diamond and its suitability for particle detection in hadron physics experiments

    Energy Technology Data Exchange (ETDEWEB)

    Pomorski, Michal

    2008-08-07

    This work presents the study on the suitability of single-crystal CVD diamond for particle-detection systems in present and future hadron physics experiments. Different characterization methods of the electrical and the structural properties were applied to gain a deeper understanding of the crystal quality and the charge transport properties of this novel semiconductor material. First measurements regarding the radiation tolerance of diamond were performed with sensors heavily irradiated with protons and neutrons. Finally, detector prototypes were fabricated and successfully tested in various experiments as time detectors for minimum ionizing particles as well as for spectroscopy of heavy ions at the energy ranges available at the SIS and the UNILAC facilities of GSI. (orig.)

  16. Development of CaMoO{sub 4} crystal scintillators for a double beta decay experiment with {sup 100}Mo

    Energy Technology Data Exchange (ETDEWEB)

    Annenkov, A.N.; Buzanov, O.A. [Moscow Steel and Alloy Institute, 119049 Moscow (Russian Federation); Danevich, F.A. [Institute for Nuclear Research, MSP 03680 Kyiv (Ukraine)], E-mail: danevich@kinr.kiev.ua; Georgadze, A.Sh. [Institute for Nuclear Research, MSP 03680 Kyiv (Ukraine); Kim, S.K. [DMRC and School of Physics, Seoul National University, Seoul 151-742 (Korea, Republic of); Kim, H.J. [Physics Department, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Kim, Y.D. [Sejong University, Seoul (Korea, Republic of); Kobychev, V.V. [Institute for Nuclear Research, MSP 03680 Kyiv (Ukraine); Kornoukhov, V.N. [Institute for Theoretical and Experimental Physics, 117218 Moscow (Russian Federation); Korzhik, M. [Institute for Nuclear Problems, 220030 Minsk (Belarus); Lee, J.I. [Sejong University, Seoul (Korea, Republic of); Missevitch, O. [Institute for Nuclear Problems, 220030 Minsk (Belarus); Mokina, V.M.; Nagorny, S.S.; Nikolaiko, A.S.; Poda, D.V.; Podviyanuk, R.B.; Sedlak, D.J.; Shkulkova, O.G. [Institute for Nuclear Research, MSP 03680 Kyiv (Ukraine); So, J.H. [Physics Department, Kyungpook National University, Daegu 702-701 (Korea, Republic of)] (and others)

    2008-01-11

    We have studied the energy resolution, {alpha}/{beta} ratio, temperature dependence of the scintillation properties, and the radioactive contamination of CaMoO{sub 4} crystal scintillators. We have also examined the use of pulse-shape discrimination to distinguish {gamma} rays and {alpha} particles. A high sensitivity experiment to search for the 0{nu}2{beta} decay of {sup 100}Mo using CaMoO{sub 4} scintillators is discussed.

  17. Densification and crystalization kinetics of mullite diphasic gels from non_isothermal dilatometry experiments

    Directory of Open Access Journals (Sweden)

    Orgaz, Felipe

    2008-12-01

    Full Text Available Mullite (3 AI2O3_2 SiO2 was processed by mixing silica and alumina colloids at pH below 3 in a high shear blender. The gels were sieved to ‹ 125 microns and cold isostatically pressed to form rods. The various processes involved during the sintering process such as condensation-polymerization and the competition between mullite crystallization and densification were analysed from constant heating rate equations and rate controlled sintering dilatometer experiments. Changes in the slopes permitted the identification of such processes and the activation energy for mullitization was calculated. Fast firing (20-30 K/min in the critical mullitization temperature range of 1230-1505ºC and low heating rates (2-3 K/min in the viscous flow densification intervals of below 1230ºC and higher than 1505 gives rise to near full density and fine grain microstructures of sintered mullite. Fast firing and high (0.5 to 1 % /min densification rate controlled processes seem to be the most suitable approaches to high density gel processed mullite. Amorphous silica is the rate controlling mechanism for the viscous flow densification process before alumina is solved and nucleation and crystallization of mullite appears. Deviations from the linear Frenkel model for viscous flow are also observed.

    Mullita de composición (3Al2O3 -2 SiO2 ha sido preparada mezclando coloides de sílice y alúmina en un mezclador de alta velocidad a pH inferior a 3. Los geles formados eran secados, tamizados por debajo de 125 micras y prensados isostáticamrente para formar varillas de unos 6 mm de diámetro. Los diferentes procesos que ocurren durante el proceso de sinterización, tales como polimerización- condensación y la competición entre cristalización y densificación, han sido analizados utilizando las ecuaciones de ecuaciones de velocidad de calentamiento constantte y experimentos

  18. Comparison and evaluation of cloud point extraction and low-temperature directed crystallization as preconcentration tools for the determination of trace elements in environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Giokas, D.L.; Eksperiandova, L.P.; Blank, A.B.; Karayannis, M.I

    2004-03-03

    A comparative study between cloud point extraction (CPE) and low-temperature directed crystallization (LTDC) is presented. Trace elements (Cd, Pb, Cr, Cu, Zn, Ni and Fe) were preconcentrated by both methods from model and natural water samples and the results were evaluated with respect to extraction efficiency, accuracy, precision, sample throughput and interferences. Flame atomic absorption spectrometry (FAAS) and inductively coupled plasma atomic emission spectrometry (ICP-AES) were used for the final measurements. The results indicate that these extraction and preconcentration procedures ensure the required accuracy and precision for the reliable identification and quantification of trace elements in natural waters. Drawbacks of each method identified can further assist the analyst towards a better application of each method depending on the target species, the detector employed and the application intended (routine analysis, trace analysis, speciation analysis, etc.)

  19. Design of an LED chip structure with an integrated two-dimensional photonic crystal to enhance the light-extraction efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Won-Sik; Park, Si-Hyun [Yeungnam University, Gyeongsan (Korea, Republic of)

    2014-05-15

    We numerically simulated the light-extraction efficiency of light-emitting diodes (LEDs) with an integrated two-dimensional photonic crystal (PC) structure on the top surface in order to enhance light extraction. We considered InGaN-based LED chips with a typical emission wavelength of λ{sub o} = 460 nm and an emission wavelength inside the LED chip of λ = λ{sub 0}/n{sub GaN} , where n{sub GaN} is the refractive index of GaN. We used positive (relief) and negative (intaglio) patterns for the PC structures with square arrangements. The pattern period (Λ), width (d), and height (h) of the PC structure were varied systematically in the PC-LEDs; then the light-extraction efficiency of each PC-LED was simulated numerically using a three-dimensional finite-difference time-domain method to optimize the PC structure in terms of light extraction. The PC LED with a square pillar pattern with Λ ∼ 1.4λ, d ∼ 0.75Λ, and h ∼ 0.75Λ had the maximum light-extraction efficiency for positive patterns while the cylindrical hole pattern with Λ ∼ 1.2λ, d ∼ 0.5Λ, and h ∼ 0.5Λ had the maximum light-extraction efficiency for negative patterns.

  20. Prevention of renal crystal deposition by an extract of Ammi visnaga L. and its constituents khellin and visnagin in hyperoxaluric rats.

    Science.gov (United States)

    Vanachayangkul, P; Chow, N; Khan, S R; Butterweck, Veronika

    2011-06-01

    In Egypt, teas prepared from the fruits of Ammi visnaga L. (syn. "Khella") are traditionally used by patients with urolithiasis. The aim of this study was to evaluate whether oral administration of an aqueous extract prepared from the fruits of A. visnaga as well as two major constituents khellin and visnagin could prevent crystal deposition in stone-forming rats. Hyperoxaluria was induced in male Sprague-Dawley rats by giving 0.75% ethylene glycol and 1% ammonium chloride via the drinking water. The Khella extract (KE; 125, 250 or 500 mg/kg) was orally administered for 14 days. The histopathological examination of the kidneys revealed that KE significantly reduced the incidence of calcium oxalate (CaOx) crystal deposition. In addition, KE significantly increased urinary excretion of citrate along with a decrease of oxalate excretion. Comparable to the extract, khellin and visnagin significantly reduced the incidence of CaOx deposition in the kidneys. However, both compounds did not affect urinary citrate or oxalate excretion indicating a mechanism of action that differs from that of the extract. For KE, a reasonably good correlation was observed between the incidence of crystal deposition, the increase in citrate excretion and urine pH suggesting a mechanisms that may interfere with citrate reabsorption. In conclusion, our data suggest that KE and its compounds, khellin and visnagin, may be beneficial in the management of kidney stone disease caused by hyperoxaluria but that it is likely that different mechanism of action are involved in mediating these effects.

  1. Fitting It All In: Adapting a Green Chemistry Extraction Experiment for Inclusion in an Undergraduate Analytical Laboratory

    Science.gov (United States)

    Buckley, Heather L.; Beck, Annelise R.; Mulvihill, Martin J.; Douskey, Michelle C.

    2013-01-01

    Several principles of green chemistry are introduced through this experiment designed for use in the undergraduate analytical chemistry laboratory. An established experiment of liquid CO2 extraction of D-limonene has been adapted to include a quantitative analysis by gas chromatography. This facilitates drop-in incorporation of an exciting…

  2. Fitting It All In: Adapting a Green Chemistry Extraction Experiment for Inclusion in an Undergraduate Analytical Laboratory

    Science.gov (United States)

    Buckley, Heather L.; Beck, Annelise R.; Mulvihill, Martin J.; Douskey, Michelle C.

    2013-01-01

    Several principles of green chemistry are introduced through this experiment designed for use in the undergraduate analytical chemistry laboratory. An established experiment of liquid CO2 extraction of D-limonene has been adapted to include a quantitative analysis by gas chromatography. This facilitates drop-in incorporation of an exciting…

  3. Interactions of carbon nanotubes in a nematic liquid crystal. II. Experiment

    Science.gov (United States)

    Agha, Hakam; Galerne, Yves

    2016-04-01

    Multiwall carbon nanotube (CNT) colloids with different anchoring conditions are dispersed in pentyl-cyanobiphenyl (5CB), a thermotropic liquid crystal (LC) that exhibits a room-temperature nematic phase. The experiments make use of CNTs treated for strong planar, homeotropic, or Janus anchorings. Observations with a polarizing microscope show that the CNTs placed in a uniform nematic field stabilize parallel or perpendicular to n depending on their anchoring conditions. In the presence of a splay-bend disclination line, they are first attracted toward it and ultimately, they get trapped on it. Their orientation relative to the line is then found to be parallel or perpendicular to it, again depending on the anchoring conditions. When a sufficient number of particles are deposited on a disclination line, they form a micro- or nanonecklace in the shape of a thin thread or of a bottle brush, with the CNTs being oriented parallel or perpendicular to the disclination line according to the anchoring treatment. The system exhibits a rich versatility, even if until now the weak anchorings appear to be difficult to control. In a next step, the necklaces may be glued by means of pyrrole electropolymerization. In this manner, we realize a true materialization of the disclination lines, and we obtain nanowires capable of conducting the electricity in the place of the initial disclinations that just worked as templates. The advantage of the method is that it finally provides nanowires that are automatically connected to predesignated three-dimensional (3D) electrodes. Such a 3D nanowiring could have important applications, as it could allow one to develop electronic circuits in the third dimension. They could thus help with increasing the transistor density per surface unit, although downsizing of integrated circuits will soon be limited to atomic sizes or so. In other words, the predicted limitation to Moore's law could be avoided. For the moment, the nanowires that we obtain

  4. Crystallization in high level waste (HLW) glass melters: Savannah River Site operational experience

    Energy Technology Data Exchange (ETDEWEB)

    Fox, Kevin M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Peeler, David K. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Kruger, Albert A. [USDOE Office of River Protection, Richland, WA (United States)

    2015-06-12

    This paper provides a review of the scaled melter testing that was completed for design input to the Defense Waste Processing Facility (DWPF) melter. Testing with prototype melters provided the data to define the DWPF operating limits to avoid bulk (volume) crystallization in the un-agitated DWPF melter and provided the data to distinguish between spinels generated by refractory corrosion versus spinels that precipitated from the HLW glass melt pool. A review of the crystallization observed with the prototype melters and the full-scale DWPF melters (DWPF Melter 1 and DWPF Melter 2) is included. Examples of actual DWPF melter attainment with Melter 2 are given. The intent is to provide an overview of lessons learned, including some example data, that can be used to advance the development and implementation of an empirical model and operating limit for crystal accumulation for a waste treatment and immobilization plant.

  5. ZnWO_4 crystals as detectors for double beta decay and dark matter experiments

    CERN Document Server

    Danevich, F A; Nagorny, S S; Poda, D V; Tretyak, V I; Yurchenko, S S; Zdesenko, Y G; Zdesenko, Yu.G.

    2004-01-01

    Energy resolution, alpha/beta ratio, and the pulse shape discrimination ability of the ZnWO_4 crystal scintillators were studied. The radioactive contamination of a ZnWO_4 crystal was investigated in the Solotvina Underground Laboratory. Possibilities to apply ZnWO_4 crystals for the dark matter and double beta decay searches are discussed. New improved half-life limits on double beta decay in zinc isotopes were established, in particular, for EC\\beta^+ decay of 64-Zn as: T_1/2^2nu > 8.9 10^18 yr and T_1/2^0nu > 3.6 10^18 yr, both at 68% CL.

  6. ZnWO{sub 4} crystals as detectors for 2{beta} decay and dark matter experiments

    Energy Technology Data Exchange (ETDEWEB)

    Danevich, F.A. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine)]. E-mail: danevich@kinr.kiev.ua; Kobychev, V.V. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine); Nagorny, S.S. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine); Poda, D.V. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine); Tretyak, V.I. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine); Yurchenko, S.S. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine); Zdesenko, Yu.G. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine)

    2005-06-01

    Energy resolution, {alpha}/{beta} ratio, and the pulse shape discrimination ability of the ZnWO{sub 4} crystal scintillators were studied. The radioactive contamination of a ZnWO{sub 4} crystal was investigated in the Solotvina Underground Laboratory. Possibilities to apply ZnWO{sub 4} crystals for the dark matter and double beta decay searches are discussed. New improved half-life limits on double beta decay in zinc isotopes were established, in particular, for -bar {beta}{sup +} decay of {sup 64}Zn as: T{sub 1/2}{sup 2{nu}}>=8.9x10{sup 18} years and T{sub 1/2}{sup 0{nu}}>=3.6x10{sup 18} years, both at 68% CL.

  7. Crystallization in high level waste (HLW) glass melters: Savannah River Site operational experience

    Energy Technology Data Exchange (ETDEWEB)

    Fox, K.

    2015-06-12

    This paper provides a review of the scaled melter testing that was completed for design input to the Defense Waste Processing Facility (DWPF) melter. Testing with prototype melters provided the data to define the DWPF operating limits to avoid bulk (volume) crystallization in the un-agitated DWPF melter and provided the data to distinguish between spinels generated by refractory corrosion versus spinels that precipitated from the HLW glass melt pool. A review of the crystallization observed with the prototype melters and the full scale DWPF melters (DWPF Melter 1 and DWPF Melter 2) is included. Examples of actual DWPF melter attainment with Melter 2 are given. The intent is to provide an overview of lessons learned, including some example data, that can be used to advance the development and implementation of an empirical model and operating limit for crystal accumulation for a waste treatment and immobilization plant.

  8. Simultaneous spectrophotometric determination of trace amount of malachite green and crystal violet in water after cloud point extraction using partial least squares regression.

    Science.gov (United States)

    An, Lin; Deng, Jian; Zhou, Liang; Li, Hui; Chen, Fei; Wang, Hui; Liu, Yating

    2010-03-15

    In this work, a new method has been proposed to simultaneously determine the trace amount of malachite green and crystal violet from aqueous solution by spectrophotometry after cloud point extraction (CPE) using partial least squares regression. The optimal extraction and operating conditions, such as pH, reagents concentration and effect of time and temperature, and so on, have been investigated using the non-ionic surfactant Triton X-114. The maximum absorption wavelength for malachite green and crystal violet is 624 and 579 nm, respectively; linearity is obeyed in the range of 9.9-800 and 16-1000 ng mL(-1) with detection limit of 2.9 and 4.8 ng mL(-1), and the root mean square error of prediction (RMSEP) are 0.0197 and 0.0343, respectively. The proposed method has been applied successfully to simultaneously determine the trace amount of malachite green and crystal violet in real matrix samples with the recoveries of 92.45-102.5%.

  9. Promotion of wound healing by Plantago major L. leaf extracts--ex-vivo experiments confirm experiences from traditional medicine.

    Science.gov (United States)

    Zubair, Muhammad; Nybom, Hilde; Lindholm, Christina; Brandner, Johanna M; Rumpunen, Kimmo

    2016-01-01

    The wound-healing properties of Plantago major L. (plantain) were evaluated using an ex-vivo porcine wound-healing model. Ethanol- and water-based extracts were prepared from greenhouse-grown and freeze-dried leaves of P. major. Both types of extracts stimulated wound healing in porcine skin, but the ethanol-based extracts had a somewhat stronger effect. A concentration of 1.0 mg/mL (on dry weight basis) produced the best results for both types of extracts.

  10. The application of time-dependent ice crystal trajectory and growth model for the evaluation of cloud seeding experiment using liquid carbon dioxide

    Science.gov (United States)

    Nishiyama, K.; Wakimizu, K.; Maki, T.; Suzuki, Y.; Morita, O.; Tomine, K.

    2012-12-01

    This study evaluated the results of cloud seeding experiment conducted on 17th January, 2008, in western Kyushu, Japan, using simplified time-dependent ice crystal growth and trajectory cloud model, which is characterized by 1) depositional diffusion growth process only of an ice crystal, and 2) the pursuit of the growing ice crystal based on wind field and ice crystal terminal velocity. For the estimation of the ice crystal growth and trajectory, the model specifies ice supersaturation ratio that expresses the degree of competition growth among ice crystals formed by LC seeding for existing water vapor, assuming no effect of natural ice crystals. The model is based on ice crystal growth along a- and c-axes depending on air temperature and ice supersatuation, according to Chen and Lamb (1994). The cloud seeding experiment was conducted by applying homogeneous nucleation (rapid cooling of air mass and subsequent formation of many ice crystals~1013/g LC) of Liquid Carbon (LC) dioxide seeding under typical winter-type snowfall-inducing weather situation characterized by the outbreak of cold air masses from the Siberia. The result of aircraft horizontally-penetrating seeding of LC into lower layer (-2 degree C) of supercooled convective cloud with 1km thickness above the freezing level led to the formation of an artificially-induced 'isolated' radar echo (the left figures of Fig. 1) in dominant 'no-natural radar echo region'. In other words, natural biases were eliminated by the formation of the isolated radar echo. This fact provides the shortcut for evaluating the result of cloud seeding experiment. In the next, the observed cloud seeding results were evaluated by estimating the trajectory of artificially-induced growing ice crystal. The results show that the trajectory of artificial ice crystals depends on the degree of completion growth mode. Free growth brings rapid growth of an ice crystal and, therefore, the ice crystal falls into lower layers for a short time

  11. Extraction and Quantitation of FD&C Red Dye #40 from Beverages Containing Cranberry Juice: A College-Level Analytical Chemistry Experiment

    Science.gov (United States)

    Rossi, Henry F., III; Rizzo, Jacqueline; Zimmerman, Devon C.; Usher, Karyn M.

    2012-01-01

    A chemical separation experiment can be an interesting addition to an introductory analytical chemistry laboratory course. We have developed an experiment to extract FD&C Red Dye #40 from beverages containing cranberry juice. After extraction, the dye is quantified using colorimetry. The experiment gives students hands-on experience in using solid…

  12. Extraction and Quantitation of FD&C Red Dye #40 from Beverages Containing Cranberry Juice: A College-Level Analytical Chemistry Experiment

    Science.gov (United States)

    Rossi, Henry F., III; Rizzo, Jacqueline; Zimmerman, Devon C.; Usher, Karyn M.

    2012-01-01

    A chemical separation experiment can be an interesting addition to an introductory analytical chemistry laboratory course. We have developed an experiment to extract FD&C Red Dye #40 from beverages containing cranberry juice. After extraction, the dye is quantified using colorimetry. The experiment gives students hands-on experience in using solid…

  13. Fourier series analysis of fractal lenses: theory and experiments with a liquid-crystal display.

    Science.gov (United States)

    Davis, Jeffrey A; Sigarlaki, Sean P; Craven, Julia M; Calvo, María Luisa

    2006-02-20

    We report on a Fourier series approach that predicts the focal points and intensities produced by fractal zone plate lenses. This approach allows us to separate the effects of the fractal order from those of the lens aperture. We implement these fractal lenses onto a liquid-crystal display and show experimental verification of our theory.

  14. Switching characteristics of an InP photonic crystal nanocavity: Experiment and theory

    DEFF Research Database (Denmark)

    Yu, Yi; Palushani, Evarist; Heuck, Mikkel

    2013-01-01

    The dynamical properties of an InP photonic crystal nanocavity are experimentally investigated using pump-probe techniques and compared to simulations based on coupled-mode theory. Excellent agreement between experimental results and simulations is obtained when employing a rate equation model co...

  15. Small core Chalcogenide photonic crystal fiber for midinfrared wavelength conversion: experiment and design

    OpenAIRE

    Xing, Sida; Grassani, Davide; Kharitonov, Svyatoslav; Billat, Adrien; Brès, Camille-Sophie

    2016-01-01

    Kerr index and dispersion parameter of a small core chalcogenide photonic crystal fiber are estimated via four-wave mixing near 2μm. From these values, new fiber design is proposed to efficiently generate idlers in mid-infrared.

  16. Crystallization and preliminary X-ray diffraction experiments of arylmalonate decarboxylase from Alcaligenes bronchisepticus

    Energy Technology Data Exchange (ETDEWEB)

    Nakasako, Masayoshi, E-mail: nakasako@phys.keio.ac.jp [Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Kanagawa 223-8522 (Japan); The RIKEN Harima Institute/SPring-8, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Obata, Rika; Okubo, Ryosuke; Nakayama, Shyuichi [Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Kanagawa 223-8522 (Japan); Miyamoto, Kenji; Ohta, Hiromichi [Department of Biosciences and Informatics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Kanagawa 223-8522 (Japan); Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Kanagawa 223-8522 (Japan)

    2008-07-01

    Crystals of arylmalonate decarboxylase from A. bronchisepticus were obtained which diffracted X-rays to a resolution of at least 3.0 Å. Arylmalonate decarboxylase catalyses the enantioselective decarboxylation of α-aryl-α-methylmalonates to produce optically pure α-arylpropionates. The enzyme was crystallized with ammonium sulfate under alkaline pH conditions with the aim of understanding the mechanism of the enantioselective reaction. X-ray diffraction data collected to a resolution of 3.0 Å at cryogenic temperature showed that the crystals belonged to the orthorhombic space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 83.13, b = 99.62, c = 139.64 Å. This suggested that the asymmetric unit would contain between four and six molecules. Small-angle X-ray scattering revealed that the enzyme exists as a monomer in solution. Thus, the assembly of molecules in the asymmetric unit was likely to have been induced during the crystallization process.

  17. Integration and use of Microgravity Research Facility: Lessons learned by the crystals by vapor transport experiment and Space Experiments Facility programs

    Science.gov (United States)

    Heizer, Barbara L.

    1992-01-01

    The Crystals by Vapor Transport Experiment (CVTE) and Space Experiments Facility (SEF) are materials processing facilities designed and built for use on the Space Shuttle mid deck. The CVTE was built as a commercial facility owned by the Boeing Company. The SEF was built under contract to the UAH Center for Commercial Development of Space (CCDS). Both facilities include up to three furnaces capable of reaching 850 C minimum, stand-alone electronics and software, and independent cooling control. In addition, the CVTE includes a dedicated stowage locker for cameras, a laptop computer, and other ancillary equipment. Both systems are designed to fly in a Middeck Accommodations Rack (MAR), though the SEF is currently being integrated into a Spacehab rack. The CVTE hardware includes two transparent furnaces capable of achieving temperatures in the 850 to 870 C range. The transparent feature allows scientists/astronauts to directly observe and affect crystal growth both on the ground and in space. Cameras mounted to the rack provide photodocumentation of the crystal growth. The basic design of the furnace allows for modification to accommodate techniques other than vapor crystal growth. Early in the CVTE program, the decision was made to assign a principal scientist to develop the experiment plan, affect the hardware/software design, run the ground and flight research effort, and interface with the scientific community. The principal scientist is responsible to the program manager and is a critical member of the engineering development team. As a result of this decision, the hardware/experiment requirements were established in such a way as to balance the engineering and science demands on the equipment. Program schedules for hardware development, experiment definition and material selection, flight operations development and crew training, both ground support and astronauts, were all planned and carried out with the understanding that the success of the program science

  18. The Influence of Crystal Size Distributions (CSD) on the Rheology of Magma: New Insights from Analogue Experiments

    Science.gov (United States)

    Klein, J.; Mueller, S.; Castro, J. M.

    2016-12-01

    Knowing the flow properties, or rheology, of magma is of great importance for volcanological research. It is vital for understanding eruptive and depositional features, modelling magma flow rates and distances, interpreting pre-eruptive volcanic unrest and earthquakes, and ultimately predicting volcanic hazards related to magma motion. Despite its key role in governing volcanic processes, magma rheology is extremely difficult to constrain in time and space within a natural volcanic system, because it is dependent upon so many variables. Therefore, both analogue and experimental studies of permissible yet simplified scenarios are needed to isolate different rheological influences. Despite significant progress in understanding the rheological properties of silicate melts and two-phase mixtures (e.g. melt + crystals), as well as the impact of the volume fraction (e.g. Pinkerton & Stevenson, 1992; Caricchi et al., 2007; Mueller et al., 2010) and shape (Mueller et al., 2011) of crystals on magma rheology, the effect of the crystal size distribution (CSD) is still poorly constrained. A highly disperse CSD (i.e., a great variety of different crystal sizes) leads to a much more efficient packing of crystals in a flowing magma which predominantly controls the rheological behavior of magma in a sheared particle Accounting for, or neglecting, the size distribution of crystals can therefore make a considerable difference in magma flow models. We present the results of systematic rheometric experiments using multimodal analogue particle suspensions of well-defined size fractions of micrometer-sized glass beads in silicone oil as magma-analogue material. Starting with simple bimodal distributions (i.e. particles of two distinct sizes), the complexity of the samples' particle size distribution has been successively increased and evaluated towards tetramodal distributions (four distinct size fractions). Statistical values of the given suspensions have been calculated and

  19. Real-Time Very High-Resolution Regional 4D Assimilation in Supporting CRYSTAL-FACE Experiment

    Science.gov (United States)

    Wang, Donghai; Minnis, Patrick

    2004-01-01

    To better understand tropical cirrus cloud physical properties and formation processes with a view toward the successful modeling of the Earth's climate, the CRYSTAL-FACE (Cirrus Regional Study of Tropical Anvils and Cirrus Layers - Florida Area Cirrus Experiment) field experiment took place over southern Florida from 1 July to 29 July 2002. During the entire field campaign, a very high-resolution numerical weather prediction (NWP) and assimilation system was performed in support of the mission with supercomputing resources provided by NASA Center for Computational Sciences (NCCS). By using NOAA NCEP Eta forecast for boundary conditions and as a first guess for initial conditions assimilated with all available observations, two nested 15/3 km grids are employed over the CRYSTAL-FACE experiment area. The 15-km grid covers the southeast US domain, and is run two times daily for a 36-hour forecast starting at 0000 UTC and 1200 UTC. The nested 3-km grid covering only southern Florida is used for 9-hour and 18-hour forecasts starting at 1500 and 0600 UTC, respectively. The forecasting system provided more accurate and higher spatial and temporal resolution forecasts of 4-D atmospheric fields over the experiment area than available from standard weather forecast models. These forecasts were essential for flight planning during both the afternoon prior to a flight day and the morning of a flight day. The forecasts were used to help decide takeoff times and the most optimal flight areas for accomplishing the mission objectives. See more detailed products on the web site http://asd-www.larc.nasa.gov/mode/crystal. The model/assimilation output gridded data are archived on the NASA Center for Computational Sciences (NCCS) UniTree system in the HDF format at 30-min intervals for real-time forecasts or 5-min intervals for the post-mission case studies. Particularly, the data set includes the 3-D cloud fields (cloud liquid water, rain water, cloud ice, snow and graupe/hail).

  20. The photon tagging facility for the Crystal-Barrel/TAPS experiment at ELSA; Die Photonenmarkierungsanlage fuer das Crystal-Barrel/TAPS-Experiment an ELSA

    Energy Technology Data Exchange (ETDEWEB)

    Fornet-Ponse, Kathrin

    2009-11-15

    With the CBELASA/TAPS experiment in the framework of the SFB/TR 16 measurements of single- and double-polarization observables in the photoporoduction were performed. The energy of the high-energetic, polarized photon beams required for this, is determined by means of a so-called tagging system. In the framework of this thesis such a tagging system was constructed. It allows the energy tagging of the photons in an energy range from 0.021.E{sub 0} to 0.871.E{sub 0} with a time resolution of {sigma}=0.240 ns and an energy resolution from 0.1%.E{sub 0} to 0.4%.E{sub 0}. The reached time resolution allows to use the tagging system as time reference for the remaining experimental components. For the calculation of cross sections the knowledge of the photon flux at the experimental target is necessary. Thereby the photon definition probability P{sub {gamma}} plays a central role, which indicates, with which probability for a signal from the tagging system the corresponding photon in the {gamma} beam at the production target is present. It could be found a prescription for the determination of P{sub {gamma}}, which yields at tagging rates from 1 MHz to 10 MHz consistent results. A relative systematic error for P{sub {gamma}} was determined. Furthermore the effects of collimation and divergence of the photon beam on the number of the really in the experiment available photons and by this on the maximally reachable P{sub {gamma}} were extensively studied and experimental observations explained. [German] Mit dem CBELSA/TAPS-Experiment werden im Rahmen des SFB/TR 16 Messungen von Einfach- und Doppelpolarisationsobservablen in der Photoproduktion durchgefuehrt. Die hochenergetischen, polarisierten Photonenstrahlen werden ueber den Bremsstrahlungsprozess erzeugt. Die Energie der Photonen bestimmt sich aus der Differenz zwischen der Elektronenergie vor (E{sub 0}) und nach (E{sub e{sup -}}) dem Bremsstrahlungsprozess. Dies erfordert den Nachweis der Sekundaerelektronen mit Hilfe

  1. Influence of substitution on the optical properties of functionalized pentacene monomers and crystals: Experiment and theory

    KAUST Repository

    Saeed, Yasir

    2013-10-01

    The influence of solubilizing substitutional groups on the electronic structure of prototypical functionalized pentacene molecules and crystals is studied by a combined experimental and theoretical approach. We experimentally establish characteristic effects of substituents on the electronic structure and relate those to theoretical optical spectra in order to explain the experimental results and provide a comprehensive picture of the substitution effects. Bands associated to C/Si atoms connecting the functional side group to the pentacene in the (6,13)-positions are the main contributors to the optical transitions. The amplitude of the redshift between the crystals and molecules provides insight in the packing structure. © 2013 Elsevier B.V. All rights reserved.

  2. T1-relaxation of 129Xe on metal single crystal surfaces—multilayer experiments on iridium and monolayer considerations

    Science.gov (United States)

    Stahl, Dirk; Mannstadt, Wolfgang; Gerhard, Peter; Koch, Matthias; Jänsch, Heinz J.

    2002-11-01

    The surface of a typical laboratory single crystal has about 10 15 surface atoms or adsorption sites, respectively, and is thus far out of reach for conventional NMR experiments using thermal polarization. It should however be in reach for NMR of adsorbed laser polarized (hyperpolarized) 129Xe, which is produced by spin transfer from optically pumped rubidium. With multilayer experiments of xenon adsorbed on an iridium surface we do not only demonstrate that monolayer sensitivity has been obtained, we also show that such surface experiments can be performed under ultra high vacuum conditions with the crystal being mounted in a typical surface analysis chamber on a manipulator with far-reaching sample heating and cooling abilities. With only four spectra summed up we present an NMR signal from at most 4×10 14 atoms of 129Xe, four layers of naturally abundant xenon, respectively. The fact that no monolayer signal has been measured so far is explained by a fast Korringa relaxation due to the Fermi contact interaction of the 129Xe nuclei with the electrons of the metal substrate. T1-relaxation times in the order of several ms have been calculated using all electron density functional theory for several metal substrates.

  3. Experiment study of wavelength conversion in a dispersion-flattened photonic crystal fiber

    Institute of Scientific and Technical Information of China (English)

    Qiuguo Wang; Bojun Yang; Lan Zhang; Hu Zhang; Li He

    2007-01-01

    @@ Wavelength conversion based on four-wave mixing (FWM) has been demonstrated using a 40-m dispersion flattened highly nonlinear photonic crystal fiber (HNL-PCF). A conversion efficiency of -26 dB for a pump power of 19.5 dBm and a conversion bandwidth of 28 nm have been obtained, which are limited by the continuous wave (CW) laser wavelength range and tunability of optical band pass filters (OBPFs).

  4. A comparison between experiment and theory on few-quantum-dot nanolasing in a photonic-crystal cavity

    DEFF Research Database (Denmark)

    Liu, Jin; Ates, Serkan; Lorke, Michael

    2013-01-01

    We present an experimental and theoretical study on the gain mechanism in a photonic-crystal-cavity nanolaser with embedded quantum dots. From time-resolved measurements at low excitation power we find that four excitons are coupled to the cavity. At high excitation power we observe a smooth low......-threshold transition from spontaneous emission to lasing. Before lasing emission sets in, however, the excitons are observed to saturate, and the gain required for lasing originates rather from multi-excitonic transitions, which give rise to a broad emission background. We compare the experiment to a model of quantum...

  5. A proof-of-principle experiment of EIT with gamma radiation in FePSe{sub 3} single crystal

    Energy Technology Data Exchange (ETDEWEB)

    Muramatsu, Hisakazu, E-mail: hmurama@shinshu-u.ac.jp [Shinshu University, Department of Chemistry, Faculty of Education (Japan); Nakajo, S.; Nakagami, K.; Nagata, K. [Shinshu University, Graduate School of Education (Japan); Mochizuki, S.; Suzuki, H. [Shinshu University, Department of Chemistry, Faculty of Education (Japan)

    2012-03-15

    From a series of Moessbauer measurements performed on a single crystal of FePSe{sub 3}, we have observed the effect of electromagnetically induced transparency (EIT) in a second nuclear system, after a first experiment using the mineral siderite FeCO{sub 3}. When the condition of nuclear level crossing was fulfilled, an obvious deficit in absorption was observed at the point of level crossing. This reduced absorption cannot be ascribed to saturation effects because of the specific geometry of the measurement. We conclude that the observed deficit in absorption is due to coherence and interference effects.

  6. Characteristics of Heavy Snowfall and Snow Crystal Habits in the ESSAY (Experiment on Snow Storms At Yeongdong) Campaign in Korea

    Science.gov (United States)

    Koh, D.

    2016-12-01

    The Yeongdong region in Korea has frequent heavy snowfall in winter, which usually results in societal and economic damages such as collapses of the greenhouse and the temporary building due to heavy snowfall weights and traffic accidents due to snow-slippery road condition. Therefore we have conducted an intensive measurement campaign of `Experiment on Snow Storms At Yeongdong (ESSAY)' using radiosonde soundings, several remote sensors and a digital camera with a magnifier for taking a photograph of snowfall crystals in the region. The analysis period is mainly limited to every winter from 2014 to 2016The typical synoptic situation for the heavy snowfall is Low pressure system passing by the far South of the Korean peninsula along with the Siberian High extending to northern Japan, leading to the northeasterly or easterly flows frequently accompanied by the long-lasting snowfall in the Yeongdong region. The snow crystal habits observed in the ESSAY campaign are mainly dendrite, consisting of about 70% of the entire habits, indicative of relatively warmer East Sea effect. Meanwhile, the rimed habits are frequently captured specifically when two-layered clouds are observed. The homogeneous habit such as dendrite is shown in case of shallow clouds with its thickness below 500 m, whereas various habits are captured such as graupel, dendrites, rimed dendrites, etc in the thicker cloud with its thickness greater than 1.5 km. The association of snow crystal habits with temperature and supersaturation in the cloud will be more discussed.

  7. Extraction and estimation of the quantity of calcium oxalate crystals in the foliage of conifer and hardwood trees

    Science.gov (United States)

    Rakesh Minocha; Bradley Chamberlain; Stephanie Long; Swathi A. Turlapati; Gloria. Quigley

    2015-01-01

    The main goal of this study was to develop a method for the extraction and indirect estimation of the quantity of calcium oxalate (CaOx) in the foliage of trees. Foliar tissue was collected from a single tree of each species (five conifers and five hardwoods) for comparison of extractions in different solvents using 10 replicates per species from the same pool of...

  8. Assessment of the antioxidant potential of selected plant extracts--in vitro and in vivo experiments on pork.

    Science.gov (United States)

    Lahucky, Rudolf; Nuernberg, Karin; Kovac, Lubomir; Bucko, Ondrej; Nuernberg, Gerd

    2010-08-01

    The antioxidant potential of selected plant extracts was assessed in vitro and in vivo experiments on pork. In the in vitro experiment, the anti-oxidative capacity of ethanol-water extract of Melissa officinalis (MW), ethanol-propylene-glycol extracts of M. officinalis (MP), Origanum vulgaris (O) and Salvia officinalis (S) at different dilutions was analysed. Furthermore a 2% essential oil concentrate was added to Origanum (OSi) and Salvia (SSi). In the two in vivo experiments in total 104 Slovak White Meaty pigs were fed with plant extracts (MW and O) at different doses with/without additional vitamin E. In the in vitro experiment Melissa (MW) showed a higher antioxidant potential compared to Origanum and Salvia assessed by TEAC assay. Addition of essential oil to Origanum improved substantially the anti-oxidative capacity. In the in vivo experiment the highest muscle anti-oxidative effect was obtained by feeding 60 ml Origanum. Small improvement in muscle antioxidant potential was observed by feeding Melissa or Origanum in combination with vitamin E. By feeding 10 ml Melissa, Origanum or Salvia the meat quality parameters such as pH(1) and pH(24), drip loss and shear force was not affected. After 5 days storage of meat the redness value was positively affected. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  9. Mass transfer in electromembrane extraction - The link between theory and experiments

    DEFF Research Database (Denmark)

    Huang, Chuixiu; Jensen, Henrik; Seip, Knut Fredrik

    2016-01-01

    and liquid–liquid extraction, and the fundamental principles for mass transfer have only partly been investigated. Thus, although there is great interest in electromembrane extraction, the fundamental principle for mass transfer has to be described in more detail for the scientific acceptance of the concept....... This review summarizes recent efforts to describe the fundamentals of mass transfer in electromembrane extraction, and aim to give an up-to-date understanding of the processes involved....... typically been combined with chromatography, mass spectrometry, and electrophoresis for analyte separation and detection. At the moment, close to 125 research papers have been published with focus on electromembrane extraction. Electromembrane extraction is a hybrid technique between electrophoresis...

  10. Radiation generation with pyroelectric crystals

    Science.gov (United States)

    Geuther, Jeffrey A.

    2007-12-01

    Pyroelectric crystals heated or cooled in vacuum have been used to produce low-energy x-ray devices since 1992. In the course of this thesis, experiments with lithium tantalate (LiTaO3) and lithium niobate (LiNbO 3) were performed to extend the usefulness of pyroelectric radiation sources. Paired-crystal x-ray generators were shown to double the x-ray energy and yield, and allow the k-shell fluorescence of any metal up to thorium (Z = 90). It was demonstrated that the electron emission from a single pyroelectric crystal could be transmitted through a beryllium window to allow the electron beam to be extracted from the vacuum chamber. The electron emission current and energy were measured, and a mathematical model was developed to predict emission current and energy. Magnetic deflection experiments were used to verify that the electric field produced by the pyroelectric effect in lithium tantalate was sufficient to ionize gas. Finally, a paired-crystal system was used to ionize a deuterium fill gas near a metallic tip mounted to a pyroelectric crystal, and accelerate these ions into a deuterated target mounted to the opposing crystal. This technique was used to produce a compact, low-power fusion neutron source driven by pyroelectric crystals.

  11. Mass transfer in electromembrane extraction--The link between theory and experiments.

    Science.gov (United States)

    Huang, Chuixiu; Jensen, Henrik; Seip, Knut Fredrik; Gjelstad, Astrid; Pedersen-Bjergaard, Stig

    2016-01-01

    Electromembrane extraction was introduced in 2006 as a totally new sample preparation concept for the extraction of charged analytes present in aqueous samples. Electromembrane extraction is based on electrokinetic migration of the analytes through a supported liquid membrane and into a μL-volume of acceptor solution under the influence of an external electrical field. To date, electromembrane extraction has mostly been used for the extraction of drug substances, amino acids, and peptides from biological fluids, and for organic micropollutants from environmental samples. Electromembrane extraction has typically been combined with chromatography, mass spectrometry, and electrophoresis for analyte separation and detection. At the moment, close to 125 research papers have been published with focus on electromembrane extraction. Electromembrane extraction is a hybrid technique between electrophoresis and liquid-liquid extraction, and the fundamental principles for mass transfer have only partly been investigated. Thus, although there is great interest in electromembrane extraction, the fundamental principle for mass transfer has to be described in more detail for the scientific acceptance of the concept. This review summarizes recent efforts to describe the fundamentals of mass transfer in electromembrane extraction, and aim to give an up-to-date understanding of the processes involved.

  12. Jamin-interferometer-setup for the determination of concentration and temperature dependent face-specific crystal growth rates from a single experiment

    Science.gov (United States)

    Eder, Cornelia; Choscz, Carsten; Müller, Vesna; Briesen, Heiko

    2015-09-01

    An interference technique that permits the investigation of the crystal growth from a temperature controlled solution is presented. Contrary to Mach-Zehnder- or Michelson-type interferometers, the Jamin-interferometer applied in this work is characterized by improved thermal and long-time stability. In consequence a single experiment may comprise several temperature steps leading to significant changes in the bulk concentration. A procedure for the automated analysis of the acquired sequence of interference patterns is presented. Within this evaluation procedure the position of the selected crystal face, the bulk concentration and the vertical concentration distribution above the crystal are determined simultaneously. Long-term single crystal growth experiments in the range from 20 to 60 °C with sucrose and lactose crystals are used to test the method. The exact bulk concentration is determined by the interferometer. The obtained results for the growth rate of sucrose are consistent with values given in the literature. The vertical concentration distribution above the two saccharide crystals differs clearly indicating that the diffusion strongly limits the sucrose growth but not the growth of the lactose crystal. The major benefit of the described setup is that the data of a single experiment are sufficient to deduce the parameters of the model equation for the growth rate as a function of temperature and supersaturation.

  13. Application of Micro-cloud point extraction for spectrophotometric determination of Malachite green, Crystal violet and Rhodamine B in aqueous samples

    Science.gov (United States)

    Ghasemi, Elham; Kaykhaii, Massoud

    2016-07-01

    A novel, green, simple and fast method was developed for spectrophotometric determination of Malachite green, Crystal violet, and Rhodamine B in water samples based on Micro-cloud Point extraction (MCPE) at room temperature. This is the first report on the application of MCPE on dyes. In this method, to reach the cloud point at room temperature, the MCPE procedure was carried out in brine using Triton X-114 as a non-ionic surfactant. The factors influencing the extraction efficiency were investigated and optimized. Under the optimized condition, calibration curves were found to be linear in the concentration range of 0.06-0.60 mg/L, 0.10-0.80 mg/L, and 0.03-0.30 mg/L with the enrichment factors of 29.26, 85.47 and 28.36, respectively for Malachite green, Crystal violet, and Rhodamine B. Limit of detections were between 2.2 and 5.1 μg/L.

  14. Superlattice Structures, Electronic Properties, and Spin Dynamics of the Partially Cu-Extracted Phase for the Composite Crystal System CuxV4O11

    Science.gov (United States)

    Onoda, Masashige; Tamura, Asato

    2017-02-01

    The crystal structures, electronic properties, and spin dynamics of CuxV4O11 with 1.2 ≤ x system, are explored through measurements of x-ray four-circle diffraction, electrochemistry, electrical resistivity, thermoelectric power, magnetization, and electron paramagnetic resonance. This system has superlattice structures mainly ascribed to the partial ordering of Cu ions. Cu1.78V4O11 is triclinic with space group Pbar{1} and the double supercell of the V4O11 substructure of the composite crystal. The significantly Cu-extracted crystal Cu1.40V4O11 has a quadruple supercell with space group P1. The electron transport for V ions is nonmetallic owing to the polaronic nature and/or phonon softening and to the random potential of Cu ions. The Curie-Weiss-type paramagnetism basically originates from the Cu2+ chain coordinated octahedrally, and the EPR relaxation at low temperatures is understood through the exchange mechanism for the dipole-dipole and anisotropic exchange interactions. The near absence of paramagnetic behaviors of V4+ ions might be due to the spin-singlet ladder model or alternating-exchange chain model depending on the superlattice structure and valence distribution. The electrochemical performance of Li rechargeable batteries using this superlattice system is about 300 A h kg-1 at voltages above 2 V.

  15. Experiments with phase transitions at very high pressure. [compressed solidifed gases, semiconductors, superconductors, and molecular crystals

    Science.gov (United States)

    Spain, I. L.

    1983-01-01

    Diamond cells were constructed for use to 1 Mbar. A refrigerator for cooling diamond cells was adapted for studies between 15 and 300 K. A cryostat for superconductivity studies between 1.5 to 300 K was constructed. Optical equipment was constructed for fluorescence, transmission, and reflectance studies. X-ray equipment was adapted for use with diamond cells. Experimental techniques were developed for X-ray diffraction studies using synchrotron radiation. AC susceptibility techniques were developed for detecting superconducting transitions. The following materials were studied: compressed solidified gases (Xe, Ar), semiconductors (Ge, Si, GaAs), superconductors (Nb3Ge, Nb3Si, Nb3As, CuCl), molecular crystals (I).

  16. Search for double beta decay of $^{116}$Cd with enriched $^{116}$CdWO$_4$ crystal scintillators (Aurora experiment)

    CERN Document Server

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

    2016-01-01

    The Aurora experiment to investigate double beta decay of $^{116}$Cd with the help of 1.162 kg cadmium tungstate crystal scintillators enriched in $^{116}$Cd to 82\\% is in progress at the Gran Sasso Underground Laboratory. The half-life of $^{116}$Cd relatively to the two neutrino double beta decay is measured with the highest up-to-date accuracy $T_{1/2}=(2.62\\pm0.14)\\times10^{19}$ yr. The sensitivity of the experiment to the neutrinoless double beta decay of $^{116}$Cd to the ground state of $^{116}$Sn is estimated as $T_{1/2} \\geq 1.9\\times10^{23}$ yr at 90\\% CL, which corresponds to the effective Majorana neutrino mass limit $\\langle m_{\

  17. Characterization of scintillating CaWO{sub 4} crystals for the CRESST experiment using two-photon excitation

    Energy Technology Data Exchange (ETDEWEB)

    Hampf, Raphael; Dandl, Thomas; Muenster, Andrea; Oberauer, Lothar; Roth, Sabine; Schoenert, Stefan; Ulrich, Andreas [Physik-Department and Excellence Cluster Universe, Technische Universitaet Muenchen, D-85747 Garching (Germany)

    2016-07-01

    In the CRESST experiment for direct dark matter search, phonon and photon signals from cryogenic CaWO{sub 4} crystals are used to search for WIMP-induced nuclear recoil events. We present a novel table-top setup in which the scintillation of CaWO{sub 4} is induced by 0.7 ns laser pulses of 355 nm wavelength. The excitation occurs via two-photon absorption in the bulk material. The scintillation light is observed by time resolved optical spectroscopy. By varying the focusing of the laser-beam the excitation density can be made high enough to study quenching effects due to exciton-exciton annihilation. This allows to perform experiments to test models for the quenching factors of different ionizing projectiles in CaWO{sub 4} which are used to identify these projectiles on an event by event basis.

  18. Design studies for a tracking upgrade of the Crystal Barrel experiment at ELSA and installation of tracking test bench

    Energy Technology Data Exchange (ETDEWEB)

    Winnebeck, Alexander

    2009-12-17

    Ever since mankind was interested in the understanding of the universe and especially the matter in it. The fundamental building blocks of matter seem to be quarks and gluons, whose interactions are investigated in hadron physics. To study this strong interaction different experimental approaches can be used. One way is to do spectroscopy similar to atomic physics. The Crystal Barrel experiment at ELSA performs spectroscopy of nucleons to learn more about the strong interaction. A major improvement of this experimental setup will be the introducing of charged particle tracking as it is shown in this thesis. Different detector concepts are discussed concerning feasibility, material budget and especially momentum resolution. It turns out that a Time Projection Chamber (TPC) is the optimal solution. Then it is shown how a prototype TPC is tested using a newly installed tracking test bench with an electron beam, and obtained results are presented. The design of the final TPC and its integration into the Crystal Barrel experiment are discussed as well as methods to calibrate the detector. (orig.)

  19. Extraction and [superscript 1]H NMR Analysis of Fats from Convenience Foods: A Laboratory Experiment for Organic Chemistry

    Science.gov (United States)

    Hartel, Aaron M.; Moore, Amy C.

    2014-01-01

    The extraction and analysis of fats from convenience foods (crackers, cookies, chips, candies) has been developed as an experiment for a second-year undergraduate organic chemistry laboratory course. Students gravimetrically determine the fat content per serving and then perform a [superscript 1]H NMR analysis of the recovered fat to determine the…

  20. Extraction and [superscript 1]H NMR Analysis of Fats from Convenience Foods: A Laboratory Experiment for Organic Chemistry

    Science.gov (United States)

    Hartel, Aaron M.; Moore, Amy C.

    2014-01-01

    The extraction and analysis of fats from convenience foods (crackers, cookies, chips, candies) has been developed as an experiment for a second-year undergraduate organic chemistry laboratory course. Students gravimetrically determine the fat content per serving and then perform a [superscript 1]H NMR analysis of the recovered fat to determine the…

  1. "In Vitro" Synthesis and Activity of Reporter Proteins in an "Escherichia coli" S30 Extract System: An Undergraduate Experiment

    Science.gov (United States)

    Higgins, Pamela J.

    2005-01-01

    This undergraduate laboratory experiment integrates multiple techniques ("in vitro" synthesis, enzyme assays, Western blotting) to determine the production and detection sensitivity of two common reporter proteins (beta-galactosidase and luciferase) within an "Escherichia coli" S30 transcription/translation extract. Comparison of the data suggests…

  2. Oscillating Hydrofoils for Tidal Energy Extraction: Experiments, Simulations and Salt Water Field Tests

    Science.gov (United States)

    Mandre, S.; Franck, J.; Breuer, K.; Fawzi, A.; Cardona, J.; Miller, M. J.; Su, Y.; Medina, A.; Loera Loera, C.; Junquera, E.; Simeski, F.; Volkmann, K.; Lorick, R.; Cowles, S.; Luiz Rocha Ribeiro, B.; Winckler, S.; Derecktor, T.

    2015-12-01

    We report on the development of a new oscillating hydrofoil technology for tidal flow energy harvesting. A series of flume experiments and computational fluid dynamics (CFD) simulations have been performed over a wide range of frequencies, f, heave amplitudes, h, and pitch angles, θ. The flume model has chord, c, of 10 cm and aspect ratio of 4.5. Mechanical power extracted is estimated from the foil trajectory, force and moment data. A robust real-time algorithm has been developed to identify the kinematics that optimizes either the total power or the Betz efficiency. Optimal efficiency is found when the pitch and heave cycles are 90 degrees out of phase, oscillating at a reduced frequency, fc/U, of approximately 0.15, with a heave amplitude of approximately 1c, and a pitch amplitude of θ=75 degrees. The high pitch amplitude and sharp leading edge of the foil generates a transient leading edge vortex on the suction side of the foil, significantly enhancing the vertical force and power. The optimal frequency ensures that the vortex generation and ultimate shedding maximize these unsteady hydrodynamic effects. The flume results, including power and efficiency, as well as flow visualization and particle image velocimetry (PIV) exhibit excellent agreement with the CFD. Furthermore, extensive CFD and physical experiments have been performed to investigate the effects of operating in confined or shallow channels. It is found that the efficiency and power generation can significantly increase in confined areas due to the acceleration of the freestream flow around the device. Finally, the Leading Edge team has designed, built, and as of this date, is currently field-testing a 1kW prototype device consisting of two foils operating in parallel. The prototype is attached to the underside of a pontoon boat, and testing is currently underway in the Narragansett Bay near Providence RI. On completion of the field tests, in October 2015, data from the prototype will be analyzed

  3. Extra-large crystal emulsion detectors towards future large-scale experiments

    CERN Document Server

    Ariga, T; Kuwabara, K; Morishima, K; Moto, M; Nishio, A; Scampoli, P; Vladymyrov, M

    2015-01-01

    Photographic emulsion is a particle tracking device which features the best spatial resolution among particle detectors. Some applications of such a detector, for example the imaging of large object with cosmic-ray muons (muon radiography) or the detection of neutrinos, require large-scale detectors. Therefore, a huge amount of detector area has to be analyzed by means of automated optical microscopes. An improvement of the readout speed is then a crucial point to make these applications possible and one way to pursue it is the availability of new type of photographic emulsions featuring a bigger silver crystal size. This would allow a lower magnification for the microscopes, a consequent larger field of view and then a faster data analysis. In this framework, we developed new types of emulsion detectors with a crystal size of 600-1000 nm, namely 3-5 times larger than the conventional ones. This would allow a 25 times faster data readout. These new photographic emulsions have shown a sufficient sensitivity an...

  4. Multi-Periodic Photonic Crystal Out-Coupling Layers for Flexible OLEDs

    DEFF Research Database (Denmark)

    Kluge, Christian; Pradana, Arfat; Adam, Jost

    2014-01-01

    Waveguide mode extraction with multi-periodic photonic crystals is studied in experiment and finite-difference time-domain (FDTD) simulations. Flexible nanostructured organic light-emitting diodes (OLEDs) are fabricated by UV nanoimprint lithography.......Waveguide mode extraction with multi-periodic photonic crystals is studied in experiment and finite-difference time-domain (FDTD) simulations. Flexible nanostructured organic light-emitting diodes (OLEDs) are fabricated by UV nanoimprint lithography....

  5. Multi-Periodic Photonic Crystal Out-Coupling Layers for Flexible OLEDs

    DEFF Research Database (Denmark)

    Kluge, Christian; Pradana, Arfat; Adam, Jost;

    2014-01-01

    Waveguide mode extraction with multi-periodic photonic crystals is studied in experiment and finite-difference time-domain (FDTD) simulations. Flexible nanostructured organic light-emitting diodes (OLEDs) are fabricated by UV nanoimprint lithography.......Waveguide mode extraction with multi-periodic photonic crystals is studied in experiment and finite-difference time-domain (FDTD) simulations. Flexible nanostructured organic light-emitting diodes (OLEDs) are fabricated by UV nanoimprint lithography....

  6. 结晶法提取乳清中乳糖工艺的研究%Extraction techniques of lactose with the method of crystallization from whey

    Institute of Scientific and Technical Information of China (English)

    赵莉; 余群力; 陈婷

    2009-01-01

    The whey wasted from casein production with fresh milk was used as raw materials. Crude lactose was extracted by removing whey protein and concentration crystallization through the single factor determination, such as pH, soaking time and crystallization of concentration. The optimum technical parameters of lactose crystallization were determined as pH 6. 8,40 minutes of soaking time and 50Be of crystallization concentration by using L9( 34) orthogonal test. Sensory of product meets the standards of primary product of QB/T 3778-1999 in indicators,lactose content,moisture content,ash and chloride content.%本试验以生产鲜奶干酪素时排放的乳清为原料,经过中和去除乳清蛋白后浓缩、结晶得到粗制乳糖.结合单因素试验确定pH值、保温时间、结晶浓度为影响乳糖提取的主要因素,结合单因素及正交试验确定最佳工艺参数为:中和pH值6.8、保温时间40 min、浓缩糖度50 Bé.所得制品的感官、乳糖含量、水分、灰分氯化物等指标均符合QB/T 3778-1999一级品标准.

  7. Monitoring extracted beams of the nuclotron accelerator complex for "energy + transmutation" experiments

    Science.gov (United States)

    Baldin, A. A.; Berlev, A. I.; Vasil'ev, S. E.; Vishnevskiy, A. V.; Vladimirova, N. M.; Kudashkin, I. V.; Makan'kin, A. M.; Paraipan, M.; Tyutyunnikov, S. I.

    2016-03-01

    A monitoring system for measuring absolute intensity and the space—time structure of extracted beams of Nuclotron based on ionization and activation methods has been created and tested. The monitoring system provides a measurement of the absolute intensity of extracted beams with a precision of 10% and beam position with a precision of 0.5 mm.

  8. Quantitative Ultrasound-Assisted Extraction for Trace-Metal Determination: An Experiment for Analytical Chemistry

    Science.gov (United States)

    Lavilla, Isela; Costas, Marta; Pena-Pereira, Francisco; Gil, Sandra; Bendicho, Carlos

    2011-01-01

    Ultrasound-assisted extraction (UAE) is introduced to upper-level analytical chemistry students as a simple strategy focused on sample preparation for trace-metal determination in biological tissues. Nickel extraction in seafood samples and quantification by electrothermal atomic absorption spectrometry (ETAAS) are carried out by a team of four…

  9. Quantitative Ultrasound-Assisted Extraction for Trace-Metal Determination: An Experiment for Analytical Chemistry

    Science.gov (United States)

    Lavilla, Isela; Costas, Marta; Pena-Pereira, Francisco; Gil, Sandra; Bendicho, Carlos

    2011-01-01

    Ultrasound-assisted extraction (UAE) is introduced to upper-level analytical chemistry students as a simple strategy focused on sample preparation for trace-metal determination in biological tissues. Nickel extraction in seafood samples and quantification by electrothermal atomic absorption spectrometry (ETAAS) are carried out by a team of four…

  10. Experiments on decolourization with 122-resin for extraction of gibberellins from solid medium under different conditions

    Institute of Scientific and Technical Information of China (English)

    WUHong-sheng; FANJia-qing; SHIGuang-hui; ZHAONan-hai

    2004-01-01

    The extracting liquid of gibberellins (Gibberella fujikurol) from solid medium for was decolorized separately with 75%,95% alcohol, and distilled water in static adsorption and vibrating way for different durations. The results showed that the content of GA3 in efflux extracted with alcohol is 10% higher than that with distilled water. With the increase of the durations of extraction,the content of GA3 increases and the dissolution of pigments also increase. For extraction of GA3 cultured in solid medium, the best decolorizing result was obtained when it was extracted with 75%-95% alcohol in static way for 1-3 h, or in a vibrating way for 30-60 min, and then to decolor in a static way for 30-60 min in 122 resin column.

  11. First results of the experiment to search for double beta decay of 106Cd with 106CdWO4 crystal scintillator in coincidence with four crystals HPGe detector

    CERN Document Server

    Tretyak, V I; Bernabei, R; Brudanin, V B; Cappella, F; Caracciolo, V; Cerulli, R; Chernyak, D M; Danevich, F A; d'Angelo, S; Incicchitti, A; Laubenstein, M; Mokina, V M; Poda, D V; Polischuk, O G; Podviyanuk, R B; Tupitsyna, I A

    2013-01-01

    An experiment to search for double beta processes in 106Cd by using cadmium tungstate crystal scintillator enriched in 106Cd (106CdWO4) in coincidence with the four crystals HPGe detector GeMulti is in progress at the STELLA facility of the Gran Sasso underground laboratory of INFN (Italy). The 106CdWO4 scintillator is viewed by a low-background photomultiplier tube through a lead tungstate crystal light-guide produced from deeply purified archaeological lead to suppress gamma quanta from the photomultiplier tube. Here we report the first results of the experiment after 3233 hours of the data taking. A few new improved limits on double beta processes in 106Cd are obtained, in particular T1/2(2nuECb+) > 8.4e20 yr at 90% C.L.

  12. Computational crystallization.

    Science.gov (United States)

    Altan, Irem; Charbonneau, Patrick; Snell, Edward H

    2016-07-15

    Crystallization is a key step in macromolecular structure determination by crystallography. While a robust theoretical treatment of the process is available, due to the complexity of the system, the experimental process is still largely one of trial and error. In this article, efforts in the field are discussed together with a theoretical underpinning using a solubility phase diagram. Prior knowledge has been used to develop tools that computationally predict the crystallization outcome and define mutational approaches that enhance the likelihood of crystallization. For the most part these tools are based on binary outcomes (crystal or no crystal), and the full information contained in an assembly of crystallization screening experiments is lost. The potential of this additional information is illustrated by examples where new biological knowledge can be obtained and where a target can be sub-categorized to predict which class of reagents provides the crystallization driving force. Computational analysis of crystallization requires complete and correctly formatted data. While massive crystallization screening efforts are under way, the data available from many of these studies are sparse. The potential for this data and the steps needed to realize this potential are discussed.

  13. Temporal properties of liquid crystal displays: implications for vision science experiments.

    Directory of Open Access Journals (Sweden)

    Tobias Elze

    Full Text Available Liquid crystal displays (LCD are currently replacing the previously dominant cathode ray tubes (CRT in most vision science applications. While the properties of the CRT technology are widely known among vision scientists, the photometric and temporal properties of LCDs are unfamiliar to many practitioners. We provide the essential theory, present measurements to assess the temporal properties of different LCD panel types, and identify the main determinants of the photometric output. Our measurements demonstrate that the specifications of the manufacturers are insufficient for proper display selection and control for most purposes. Furthermore, we show how several novel display technologies developed to improve fast transitions or the appearance of moving objects may be accompanied by side-effects in some areas of vision research. Finally, we unveil a number of surprising technical deficiencies. The use of LCDs may cause problems in several areas in vision science. Aside from the well-known issue of motion blur, the main problems are the lack of reliable and precise onsets and offsets of displayed stimuli, several undesirable and uncontrolled components of the photometric output, and input lags which make LCDs problematic for real-time applications. As a result, LCDs require extensive individual measurements prior to applications in vision science.

  14. Crystallization and preliminary neutron diffraction experiment of human farnesyl pyrophosphate synthase complexed with risedronate.

    Science.gov (United States)

    Yokoyama, Takeshi; Ostermann, Andreas; Mizuguchi, Mineyuki; Niimura, Nobuo; Schrader, Tobias E; Tanaka, Ichiro

    2014-04-01

    Nitrogen-containing bisphosphonates (N-BPs), such as risedronate and zoledronate, are currently used as a clinical drug for bone-resorption diseases and are potent inhibitors of farnesyl pyrophosphate synthase (FPPS). X-ray crystallographic analyses of FPPS with N-BPs have revealed that N-BPs bind to FPPS with three magnesium ions and several water molecules. To understand the structural characteristics of N-BPs bound to FPPS, including H atoms and hydration by water, neutron diffraction studies were initiated using BIODIFF at the Heinz Maier-Leibnitz Zentrum (MLZ). FPPS-risedronate complex crystals of approximate dimensions 2.8 × 2.5 × 1.5 mm (∼3.5 mm(3)) were obtained by repeated macro-seeding. Monochromatic neutron diffraction data were collected to 2.4 Å resolution with 98.4% overall completeness. Here, the first successful neutron data collection from FPPS in complex with N-BPs is reported.

  15. Temporal properties of liquid crystal displays: implications for vision science experiments.

    Science.gov (United States)

    Elze, Tobias; Tanner, Thomas G

    2012-01-01

    Liquid crystal displays (LCD) are currently replacing the previously dominant cathode ray tubes (CRT) in most vision science applications. While the properties of the CRT technology are widely known among vision scientists, the photometric and temporal properties of LCDs are unfamiliar to many practitioners. We provide the essential theory, present measurements to assess the temporal properties of different LCD panel types, and identify the main determinants of the photometric output. Our measurements demonstrate that the specifications of the manufacturers are insufficient for proper display selection and control for most purposes. Furthermore, we show how several novel display technologies developed to improve fast transitions or the appearance of moving objects may be accompanied by side-effects in some areas of vision research. Finally, we unveil a number of surprising technical deficiencies. The use of LCDs may cause problems in several areas in vision science. Aside from the well-known issue of motion blur, the main problems are the lack of reliable and precise onsets and offsets of displayed stimuli, several undesirable and uncontrolled components of the photometric output, and input lags which make LCDs problematic for real-time applications. As a result, LCDs require extensive individual measurements prior to applications in vision science.

  16. Fractional reactive extraction for symmetrical separation of 4-nitro-D,L-phenylalanine in centrifugal contactor separators: experiments and modeling.

    Science.gov (United States)

    Tang, Kewen; Wen, Ping; Zhang, Panliang; Huang, Yan

    2015-01-01

    The enantioselective liquid-liquid extraction of 4-nitro-D,L-phenylalanine (D,L-Nphy) using PdCl2 {(s)-BINAP} as extractant in dichloroethane was studied experimentally in a countercurrent cascade of 10 centrifugal contactor separators (CCSs) at 5°C, involving flow ratio, extractant concentration, and Cl(-) concentration. The steady-state enantiomeric excess (ee) in both stream exits was 90.86% at a 93.29% yield. The predicted value was modeled using an equilibrium stage approach. The correlation between model and experiment was satisfactory. The model was applied to optimize the production of both enantiomers in >97% ee and >99% ee. 14 stages and 16 stages are required for 97% ee and 99% ee for both enantiomers, respectively.

  17. Production, Extraction, and Qualitative Testing of Penicillin: A Biochemistry Experiment for Health Science Chemistry Courses

    Science.gov (United States)

    Stevens, Richard E.; Billingsley, Kara C.

    1998-10-01

    This laboratory procedure guides students through the growth of a submerged Penicillium chrysogenum culture. Subsequent steps include extraction of the penicillin by adsorption onto activated charcoal, extraction with acetone, and qualitative testing of the drug on a bacterial culture. The laboratory procedure is designed for freshman-level health science chemistry courses. This procedure produces minimal waste, which can be disposed of by the appropriate use of an autoclave.

  18. Protein Crystallization

    Science.gov (United States)

    Chernov, Alexander A.

    2005-01-01

    Nucleation, growth and perfection of protein crystals will be overviewed along with crystal mechanical properties. The knowledge is based on experiments using optical and force crystals behave similar to inorganic crystals, though with a difference in orders of magnitude in growing parameters. For example, the low incorporation rate of large biomolecules requires up to 100 times larger supersaturation to grow protein, rather than inorganic crystals. Nucleation is often poorly reproducible, partly because of turbulence accompanying the mixing of precipitant with protein solution. Light scattering reveals fluctuations of molecular cluster size, its growth, surface energies and increased clustering as protein ages. Growth most often occurs layer-by-layer resulting in faceted crystals. New molecular layer on crystal face is terminated by a step where molecular incorporation occurs. Quantitative data on the incorporation rate will be discussed. Rounded crystals with molecularly disordered interfaces will be explained. Defects in crystals compromise the x-ray diffraction resolution crucially needed to find the 3D atomic structure of biomolecules. The defects are immobile so that birth defects stay forever. All lattice defects known for inorganics are revealed in protein crystals. Contribution of molecular conformations to lattice disorder is important, but not studied. This contribution may be enhanced by stress field from other defects. Homologous impurities (e.g., dimers, acetylated molecules) are trapped more willingly by a growing crystal than foreign protein impurities. The trapped impurities induce internal stress eliminated in crystals exceeding a critical size (part of mni for ferritin, lysozyme). Lesser impurities are trapped from stagnant, as compared to the flowing, solution. Freezing may induce much more defects unless quickly amorphysizing intracrystalline water.

  19. Wall modified photonic crystal fibre capillaries as porous layer open tubular columns for in-capillary micro-extraction and capillary chromatography.

    Science.gov (United States)

    Kazarian, Artaches A; Sanz Rodriguez, Estrella; Deverell, Jeremy A; McCord, James; Muddiman, David C; Paull, Brett

    2016-01-28

    Wall modified photonic crystal fibre capillary columns for in-capillary micro-extraction and liquid chromatographic separations is presented. Columns contained 126 internal parallel 4 μm channels, each containing a wall bonded porous monolithic type polystyrene-divinylbenzene layer in open tubular column format (PLOT). Modification longitudinal homogeneity was monitored using scanning contactless conductivity detection and scanning electron microscopy. The multichannel open tubular capillary column showed channel diameter and polymer layer consistency of 4.2 ± 0.1 μm and 0.26 ± 0.02 μm respectively, and modification of 100% of the parallel channels with the monolithic polymer. The modified multi-channel capillaries were applied to the in-capillary micro-extraction of water samples. 500 μL of water samples containing single μg L(-1) levels of polyaromatic hydrocarbons were extracted at a flow rate of 10 μL min(-1), and eluted in 50 μL of acetonitrile for analysis using HPLC with fluorescence detection. HPLC LODs were 0.08, 0.02 and 0.05 μg L(-1) for acenaphthene, anthracene and pyrene, respectively, with extraction recoveries of between 77 and 103%. The modified capillaries were also investigated briefly for direct application to liquid chromatographic separations, with the retention and elution of a standard protein (cytochrome c) under isocratic conditions demonstrated, proving chromatographic potential of the new column format, with run-to-run retention time reproducibility of below 1%.

  20. Light extraction improvement of InGaN light-emitting diodes with large-area highly ordered ITO nanobowls photonic crystal via self-assembled nanosphere lithography

    Directory of Open Access Journals (Sweden)

    Kui Wu

    2013-09-01

    Full Text Available The InGaN multiple quantum well light-emitting diodes (LEDs with different sizes of indium-tin-oxide (ITO nanobowl photonic crystal (PhC structure has been fabricated using self-assembled monolayer nanosphere lithography. The light output power (LOP of PhC LEDs (at 350 mA has been enhanced by 63.5% and the emission divergence exhibits a 28.8° reduction compared to conventional LEDs without PhC structure. Current-Voltage curves have shown that these PhC structures on ITO layer will not degrade the LED electrical properties. The finite-difference time-domain simulation (FDTD has also been performed for light extraction and emission characteristics, which is consistent with the experimental results.

  1. Capillary effects in guided crystallization of organic thin films

    Directory of Open Access Journals (Sweden)

    Alta Fang

    2015-03-01

    Full Text Available Recently, it has been demonstrated that solvent-vapor-induced crystallization of triethylsilylethynyl anthradithiophene (TES ADT thin films can be directed on millimeter length scales along arbitrary paths by controlling local crystal growth rates via pre-patterning the substrate. Here, we study the influence of capillary effects on crystallization along such channels. We first derive an analytical expression for the steady-state growth front velocity as a function of channel width and validate it with numerical simulations. Then, using data from TES ADT guided crystallization experiments, we extract a characteristic channel width, which provides the smallest feature size that can be obtained by this technique.

  2. Design, R&D and status of the crystal calorimeter for the Mu2e experiment

    CERN Document Server

    ,

    2016-01-01

    The Mu2e Experiment at Fermilab will search for coherent, neutrinoless conversion of muons into electrons in the field of a nucleus, with a sensitivity improvement of a factor of 10^4 over previous experiments. Such a charged lepton flavor-violating reaction probes new physics at a scale inaccessible with direct searches at either present or planned high energy colliders. The conversion electron is mono-energetic with an energy slightly below the muon rest mass. If no events are observed in three years of running, Mu2e will set a limit on the ratio between the conversion rate and the capture rate, R_{\\mu e}, of < 6 x 10^{-17} (@ 90% CL). In this paper, the physics motivation for Mu2e and the current status of the electromagnetic calorimeter project are briefly presented.

  3. Measurement of beam asymmetries in the reaction {gamma}p {yields} p{pi}{sup 0}{eta} with the Crystal Barrel/TAPS experiment at ELSA

    Energy Technology Data Exchange (ETDEWEB)

    Gutz, Eric Paul-Maria

    2011-07-01

    The photoproduction of mesons off the nucleon provides an excellent tool to gain further insight into the structure of baryons and their excitation spectrum. A large number of final states yielding various resonance contributions are accessible in photoproduction experiments. Especially in the regime of high-lying resonances, the photoproduction of multi-meson final states is of increasing importance, giving access to sequential decays of such resonances via e.g. {delta}(1232)P{sub 33} or N(1535)S{sub 11} in the intermediate state. For a complete understanding of the processes involved, however, it is insufficient to measure only unpolarized total and differential cross sections. The extraction of polarization observables from data obtained using polarized beams and targets is mandatory to constrain theoretical models and analyses and to uniquely determine the amplitudes participating in a given process. This work presents the analysis of data taken with the Crystal-Barrel/TAPS experiment at the accelerator facility ELSA in Bonn, using a linearly polarized photon beam impinging on a liquid hydrogen target. The detector system is optimized for the detection of multi-photon final states. The data has been selected for the reaction {gamma}p {yields} p{pi}{sup 0}{eta} {yields} p4{gamma} for an incoming photon energy range of 970 MeV to 1650 MeV. In this range, photon polarizations of up to 50% have been achieved. From this data, all polarization observables accessible with a linearly polarized photon beam and an unpolarized target have been extracted. This includes the beam asymmetry sum, determined as a function of various invariant masses and angles using a quasi two-body approach, along with the three-body asymmetries I{sup c} and I{sup s}. The latter two observables are unique to the acoplanar kinematics of multi-meson final states and have been measured for the first time within this work. The comparison of the results to solutions derived from various theoretical

  4. Hard x-ray transmission curved crystal spectrometers(10–100 keV) for laser fusion experiments at the ShenGuang-Ⅲ laser facility

    Institute of Scientific and Technical Information of China (English)

    Ming-hai Yu; Guang-yue Hu; Ning An; Feng Qian; Yu-chi Wu; Xiao-ding Zhang; Yu-qiu Gu; Qiu-ping Wang; Jian Zheng

    2016-01-01

    Two transmission curved crystal spectrometers are designed to measure the hard x-ray emission in the laser fusion experiment of Compton radiography of implosion target on ShenGuang-III laser facility in China. Cylindrically curvedα-quartz(10–11) crystals with curvature radii of 150 and 300 mm are used to cover spectral ranges of 10–56 and17–100 ke V, respectively. The distance between the crystal and the x-ray source can be changed over a broad distance from 200 to 1500 mm. The optical design, including the integral reflectivity of the curved crystal, the sensitivity, and the spectral resolution of the spectrometers, is discussed. We also provide mechanic design details and experimental results using a Mo anode x-ray source. High-quality spectra were obtained. We confirmed that the spectral resolution can be improved by increasing the working distance, which is the distance between the recording medium and the Rowland circle.

  5. Results from a compound semiconductor crystal growth experiment in a low gravity environment

    Science.gov (United States)

    Crouch, Roger K.; Fripp, Archibald L.; Debnam, William J.; Woodell, Glenn A.; Clark, Ivan O.

    1987-01-01

    A directional solidification experiment in the compound semiconductor lead tin telluride has been carried out in a low-gravity environment on board the Space Shuttle during a flight in October, 1985. Optical etching techniques and concentration profiles from wavelength dispersive electron microscopy indicate that there was a significant amount of convection during the solidifcation of the sample. A preliminary hypothesis of this result, that even at gravity levels on the order of 0.0001 g, the convective forces can be significant compared to mass transport due to diffusion, is being tested.

  6. Crystal accumulation in the Hanford Waste Treatment Plant high level waste melter: Summary of FY2016 experiements

    Energy Technology Data Exchange (ETDEWEB)

    Fox, K. [Savannah River Site (SRS), Aiken, SC (United States); Fowley, M. [Savannah River Site (SRS), Aiken, SC (United States); Miller, D. [Savannah River Site (SRS), Aiken, SC (United States)

    2016-12-01

    Five experiments were completed with the full-scale, room temperature Hanford Waste Treatment and Immobilization Plant (WTP) high-level waste (HLW) melter riser test system to observe particle flow and settling in support of a crystal tolerant approach to melter operation. A prototypic pour rate was maintained based on the volumetric flow rate. Accumulation of particles was observed at the bottom of the riser and along the bottom of the throat after each experiment. Measurements of the accumulated layer thicknesses showed that the settled particles at the bottom of the riser did not vary in thickness during pouring cycles or idle periods. Some of the settled particles at the bottom of the throat were re-suspended during subsequent pouring cycles, and settled back to approximately the same thickness after each idle period. The cause of the consistency of the accumulated layer thicknesses is not year clear, but was hypothesized to be related to particle flow back to the feed tank. Additional experiments reinforced the observation of particle flow along a considerable portion of the throat during idle periods. Limitations of the system are noted in this report and may be addressed via future modifications. Follow-on experiments will be designed to evaluate the impact of pouring rate on particle re-suspension, the influence of feed tank agitation on particle accumulation, and the effect of changes in air lance positioning on the accumulation and re-suspension of particles at the bottom of the riser. A method for sampling the accumulated particles will be developed to support particle size distribution analyses. Thicker accumulated layers will be intentionally formed via direct addition of particles to select areas of the system to better understand the ability to continue pouring and re-suspend particles. Results from the room temperature system will be correlated with observations and data from the Research Scale Melter (RSM) at Pacific Northwest National Laboratory

  7. Twin migration in Fe-based bcc crystals: theory and experiments

    Science.gov (United States)

    Ojha, A.; Sehitoglu, H.; Patriarca, L.; Maier, H. J.

    2014-06-01

    We establish an overall energy expression to determine the twin migration stress in bcc metals. Twin migration succeeds twin nucleation often after a load drop, and a model to establish twin migration stress is of paramount importance. We compute the planar fault energy barriers and determine the elastic energies of twinning dislocations including the role of residual dislocations (br) and twin intersection types such as ?1 1 0?, ?1 1 3? and ?2 1 0?. The energy expression derived provides the twin migration stress in relation to the twin nucleation stress with a ratio of 0.5-0.8 depending on the resultant residual burgers vector and the intersection types. Utilizing digital image correlation, it was possible to differentiate the twin nucleation and twin advancement events experimentally, and transmission electron microscopy observations provided further support to the modelling efforts. Overall, the methodology developed provides an enhanced understanding of twin progression in bcc metals, and most importantly the proposed model does not rely on empirical constants. We utilize Fe-50at.%Cr in our experiments, and subsequently predict the twin migration stress for pure Fe, and Fe-3at.%V from the literature showing excellent agreement with experiments.

  8. First spin-resolved electron distributions in crystals from combined polarized neutron and X-ray diffraction experiments

    Directory of Open Access Journals (Sweden)

    Maxime Deutsch

    2014-05-01

    Full Text Available Since the 1980s it has been possible to probe crystallized matter, thanks to X-ray or neutron scattering techniques, to obtain an accurate charge density or spin distribution at the atomic scale. Despite the description of the same physical quantity (electron density and tremendous development of sources, detectors, data treatment software etc., these different techniques evolved separately with one model per experiment. However, a breakthrough was recently made by the development of a common model in order to combine information coming from all these different experiments. Here we report the first experimental determination of spin-resolved electron density obtained by a combined treatment of X-ray, neutron and polarized neutron diffraction data. These experimental spin up and spin down densities compare very well with density functional theory (DFT calculations and also confirm a theoretical prediction made in 1985 which claims that majority spin electrons should have a more contracted distribution around the nucleus than minority spin electrons. Topological analysis of the resulting experimental spin-resolved electron density is also briefly discussed.

  9. Extraction of volatile oil from aromatic plants with supercritical carbon dioxide: experiments and modeling.

    Science.gov (United States)

    Coelho, Jose P; Cristino, Ana F; Matos, Patrícia G; Rauter, Amélia P; Nobre, Beatriz P; Mendes, Rui L; Barroso, João G; Mainar, Ana; Urieta, Jose S; Fareleira, João M N A; Sovová, Helena; Palavra, António F

    2012-09-05

    An overview of the studies carried out in our laboratories on supercritical fluid extraction (SFE) of volatile oils from seven aromatic plants: pennyroyal (Mentha pulegium L.), fennel seeds (Foeniculum vulgare Mill.), coriander (Coriandrum sativum L.), savory (Satureja fruticosa Béguinot), winter savory (Satureja montana L.), cotton lavender (Santolina chamaecyparisus) and thyme (Thymus vulgaris), is presented. A flow apparatus with a 1 L extractor and two 0.27 L separators was built to perform studies at temperatures ranging from 298 to 353 K and pressures up to 30.0 MPa. The best compromise between yield and composition compared with hydrodistillation (HD) was achieved selecting the optimum experimental conditions of extraction and fractionation. The major differences between HD and SFE oils is the presence of a small percentage of cuticular waxes and the relative amount of thymoquinone, an oxygenated monoterpene with important biological properties, which is present in the oils from thyme and winter savory. On the other hand, the modeling of our data on supercritical extraction of volatile oil from pennyroyal is discussed using Sovová's models. These models have been applied successfully to the other volatile oil extractions. Furthermore, other experimental studies involving supercritical CO(2) carried out in our laboratories are also mentioned.

  10. Atraumatic tooth extraction in patients taking bisphosphonates: a review of literature and experience with three cases.

    Science.gov (United States)

    Hoefert, Sebastian; Grimm, Martin; Sharghi, Feraydoon; Geist, Andreas; Krimmel, Michael; Reinert, Siegmar

    2014-09-01

    Regev et al. first re-introduced the method of atraumatic tooth extraction with orthodontic elastics in 2008. Since then, the method has been mentioned regularly in literature. Nevertheless, the need for additional more detailed information remains. We present a review of literature and a retrospective analysis of our three patients receiving bisphosphonate medication. Two of our patients suffered from bisphosphonate-related osteonecrosis of the jaw (BRONJ). All three patients underwent atraumatic tooth extraction, which we describe in detail. Regev et al. reported satisfactory results using the novel method. We removed six teeth in two patients with continued chemotherapy or bisphosphonate therapy in a time span of 26.2 ± 16.4 weeks successfully. None of the patients developed exposed bone in the follow-up (7.4 ± 0.2 months). In one case, the technique had to be discontinued due to increasing tooth soreness. Atraumatic tooth extraction seems to be a safe method to prevent bone exposure, even in cases with BRONJ. The time required of our patients for exfoliation exceeded the time mentioned in literature considerably. This proved to be a major limitation. Our cases showed that patients with good compliance, no sore teeth, or painful BRONJ lesions, benefited from atraumatic tooth extraction. One of the method's major advantages might be the possibility to continue chemotherapy and bisphosphonate therapy throughout the treatment.

  11. Extraction of Volatile Oil from Aromatic Plants with Supercritical Carbon Dioxide: Experiments and Modeling

    Directory of Open Access Journals (Sweden)

    Helena Sovová

    2012-09-01

    Full Text Available An overview of the studies carried out in our laboratories on supercritical fluid extraction (SFE of volatile oils from seven aromatic plants: pennyroyal (Mentha pulegium L., fennel seeds (Foeniculum vulgare Mill., coriander (Coriandrum sativum L., savory (Satureja fruticosa Béguinot, winter savory (Satureja montana L., cotton lavender (Santolina chamaecyparisus and thyme (Thymus vulgaris, is presented. A flow apparatus with a 1 L extractor and two 0.27 L separators was built to perform studies at temperatures ranging from 298 to 353 K and pressures up to 30.0 MPa. The best compromise between yield and composition compared with hydrodistillation (HD was achieved selecting the optimum experimental conditions of extraction and fractionation. The major differences between HD and SFE oils is the presence of a small percentage of cuticular waxes and the relative amount of thymoquinone, an oxygenated monoterpene with important biological properties, which is present in the oils from thyme and winter savory. On the other hand, the modeling of our data on supercritical extraction of volatile oil from pennyroyal is discussed using Sovová’s models. These models have been applied successfully to the other volatile oil extractions. Furthermore, other experimental studies involving supercritical CO2 carried out in our laboratories are also mentioned.

  12. Teaching Sustainable Development Concepts in the Laboratory: A Solid-Liquid Extraction Experiment

    Science.gov (United States)

    Parajo, Juan Carlos; Dominguez, Herminia; Santos, Valentin; Alonso, Jose Luis; Garrote, Gil

    2008-01-01

    One of the principles of sustainable development is to replace chemicals traditionally derived from oil with alternative, renewable materials. For example, phenol and phenol derivatives currently used in the manufacture of wood adhesives can be replaced (at least in part) by biopolymers extracted from biomass. In this work, pine bark (a renewable…

  13. Experiments on the extraction and photoconversion of chenopodium chlorophyll protein CP 668

    NARCIS (Netherlands)

    Terpstra, Willemke

    1966-01-01

    1. 1. The amount of extractable, photoconvertible, protein-chlorophyll complex CP 668 from Chenopodium album leaves was found to be very variable, depending on site and day of leaf collection. 2. 2. Photoconversion of CP 668 into a 740-nm absorbing form probably does not occur in intact leaves;

  14. [Extraction of 10-Deacetyl Baccatin by Supercritical CO2 from Taxus yunnanensis Branches and Leaves].

    Science.gov (United States)

    Tang, Yang-qin; Li, Hai-chi; Huang, Wen-jie; Xiong, Yan; Ge, Fa-huan

    2015-04-01

    To study the supercritical CO2 fluids extraction (SFE) method to extract the components from Taxus yunnanensis. Medicinal meterials were extracted by supercritical CO2, and then purified by industrial chromatography. Using the extraction yield of 10-DAB as the index,single factor test was carried out to investigate the effect of co-solvent, extraction time, extraction pressure, extraction temperature, pressure and temperature of separation kettle I. Then orthogonal experiment was used to optimize the best extraction condition. The suitable extraction condition was as follows: the ratio of co-solvent (80% ethanol) amount and the madicinal materials was 3: 1, Separation kettle I pressure was 14 MPa, separation kettle I temperature was 40 °C, extraction pressure was 25 MPa, extraction temperature was 60 T and extraction time was 90 min. The extract was separated by industrial chromatographic and then crystallized. The supercritical CO2 extraction and purification process of 10-DAB were simple and feasible.

  15. Impurity effects on the band structure of one-dimensional photonic crystals: Experiment and theory

    CERN Document Server

    Luna-Acosta, G A; Kuhl, U; Stoeckmann, H -J

    2007-01-01

    We study the effects of single impurities on the transmission in microwave realizations of the photonic Kronig-Penney model, consisting of arrays of Teflon pieces alternating with air spacings in a microwave guide. As only the first propagating mode is considered, the system is essentially one dimensional obeying the Helmholtz equation. We derive analytical closed form expressions from which the band structure, frequency of defect modes, and band profiles can be determined. These agree very well with experimental data for all types of single defects considered (e. g. interstitial, substitutional) and shows that our experimental set-up serves to explore some of the phenomena occurring in more sophisticated experiments. Conversely, based on the understanding provided by our formulas, information about the unknown impurity can be determined by simply observing certain features in the experimental data for the transmission. Further, our results are directly applicable to the closely related quantum 1D Kronig-Penn...

  16. Impurity effects on the band structure of one-dimensional photonic crystals: experiment and theory

    Energy Technology Data Exchange (ETDEWEB)

    Luna-Acosta, G A [Instituto de Fisica, BUAP Apartado Postal J-48, 72570 Puebla (Mexico); Schanze, H; Kuhl, U; Stoeckmann, H-J [Fachbereich Physik der Philipps-Universitaet Marburg, Renthof 5, D-35032 (Germany)], E-mail: gluna@sirio.ifuap.buap.mx

    2008-04-15

    We study the effects of single impurities on the transmission in microwave realizations of the photonic Kronig-Penney model, consisting of arrays of Teflon pieces alternating with air spacings in a microwave guide. As only the first propagating mode is considered, the system is essentially one-dimensional (1D) obeying the Helmholtz equation. We derive analytical closed form expressions from which the band structure, frequency of defect modes and band profiles can be determined. These agree very well with experimental data for all types of single defects considered (e.g. interstitial and substitutional) and show that our experimental set-up serves to explore some of the phenomena occurring in more sophisticated experiments. Conversely, based on the understanding provided by our formulae, information about the unknown impurity can be determined by simply observing certain features in the experimental data for the transmission. Further, our results are directly applicable to the closely related quantum 1D Kronig-Penney model.

  17. Application of Bent Crystals at IHEP 70-GeV Accelerator to Enhance the Efficiency of its Usage

    CERN Document Server

    Afonin, A G; Chesnokov, Yu A; Fedotov, Yu S; Galjaev, A N; Gres, V N; Ivanov, Yu B; Kotov, V I; Maisheev, V A; Medvedev, V A; Minchenko, A V; Scandale, Walter; Terekhov, V I; Troyanov, E F; Zapolskii, V N; Zelenov, B A

    2000-01-01

    Bent crystal was extracting 70-GeV protons with average intensity 4x10$^{11}$ (as measured in external beamline) per spill of ~1.6 s duration, in parallel to the simultaneous work of two internal targets in the accelerator ring. An additional crystal, placed in the external beamline, was deflecting a small part of the extracted beam with intensity ~10$^7$ protons toward another physics experiment. Crystal-extracted beam had a typical size of 4 mm by 4 mm fwhm at the end of the external beamline. Measurements for the extraction efficiency and other characteristics at the simultaneous work of four experimental set-ups are presented. With crystal working in the above-said regime during one month, no degradation of channeling was observed. The studies of extraction efficiency have been continued with new crystals.

  18. Extraction of cellulose nano-crystals from old corrugated container fiber using phosphoric acid and enzymatic hydrolysis followed by sonication.

    Science.gov (United States)

    Tang, Yanjun; Shen, Xiaochuang; Zhang, Junhua; Guo, Daliang; Kong, Fangong; Zhang, Nan

    2015-07-10

    Due to its amazing physicochemical properties and high environmental compatibility, cellulose nano-crystals (CNC) hold great promise for serving as a strategic platform for sustainable development. Now, there has been growing interest in the development of processes using waste or residual biomass as CNC source for addressing economic and environmental concerns. In the present work, a combined process involving phosphoric acid hydrolysis, enzymatic hydrolysis and sonication was proposed aiming to efficiently exact CNC from low-cost old corrugated container (OCC) pulp fiber. The effect of enzymatic hydrolysis on the yield and microstructure of resulting CNC was highlighted. Results showed that the enzymatic hydrolysis was effective in enhancing CNC yield after phosphoric acid hydrolysis. CNC was obtained with a yield of 23.98 wt% via the combined process with phosphoric acid concentration of 60 wt%, cellulase dosage of 2 mL (84 EGU) per 2g fiber and sonication intensity of 200 W. Moreover, the presence of enzymatic hydrolysis imparted the obtained CNC with improved dispersion, increased crystallinity and thermal stability.

  19. Biochar as a sorbent for chlorinated hydrocarbons - sorption and extraction experiments in single and bi-solute systems

    Science.gov (United States)

    Schreiter, Inga J.; Wefer-Roehl, Annette; Graber, Ellen R.; Schüth, Christoph

    2017-04-01

    Biochar (BC) is increasingly deemed a potential sorbent for contaminants in soil and water remediation, and brownfield restoration. In this study, sorption and extraction experiments were performed to assess the potential of three different BCs to sorb and retain the chlorinated hydrocarbons trichloroethylene (TCE) and tetrachloroethylene (PCE). BCs studied were produced from wood chips, grain husk, and cattle manure at 450 °C. A commercially available activated carbon (AC) served as a reference. The sorption behaviour was studied in batch experiments in single solute and bi-solute systems. Resulting isotherms were fitted to the Freundlich model. To assess the desorption behaviour, a five-step extraction scheme (water at 40°C, water at 80°C, methanol at 50°C, toluene at 50°C, and n-hexane at 50°) was developed, utilizing Accelerated Solvent Extraction. Isotherms revealed distinct differences in sorption behaviour depending on BC feedstock. Sorption capacity ranked as follows: wood chip BC > grain husk BC > cattle manure BC for both contaminants. This sequence could be attributable to an increasing specific surface area, an increasing amount of carbon, and a decreasing ash content of the sorbents. It is noteworthy that all three BCs were more effective in adsorbing TCE, which is surprising, given the higher logKow of PCE. The reverse was observed for the AC. Here, sorption is purely driven by the hydrophobicity of the compound rather than sorbent properties. In bi-solute experiments, PCE sorbed as good as or stronger than TCE, yet the total mass of sorbed compounds increased slightly. In contrast, AC showed a significant decrease of TCE sorption and no significant changes in the total mass sorbed. Extraction experiments revealed that for all BCs a large fraction of the contaminants could not be readily desorbed. In all cases, water remobilized < 5 % of the total contaminant mass and up to 70 % could not be extracted by any of the solvents. The findings suggest

  20. Refinement of the theory for extracting cell dielectric properties from dielectrophoresis and electrorotation experiments.

    Science.gov (United States)

    Lei, U; Sun, Pei-Hou; Pethig, Ronald

    2011-12-01

    A modified theory is proposed for extracting cell dielectric properties from the peak frequency measurement of electrorotation (ER) and the crossover frequency measurement of dielectrophoresis (DEP). Current theory in the literature is based on the low frequency (DC) approximations for the equivalent cell permittivity and conductivity, which are valid when the measurements are performed in a medium with conductivity less than 1 mS/m. The present theory extracts the cell properties through optimizing an expression for the medium conductivity in terms of the peak ER, or DEP crossover, frequency according to its definition using full expressions of equivalent cell permittivity and conductivity. Various levels of approximation of the theory are proposed and discussed through a scaling analysis. The present theory can extract both membrane and interior properties from the low and the high peak ER, or DEP crossover, frequencies for any medium conductivity provided the peak ER, or DEP crossover, frequency exists. It can be reduced to the linear theory for the low peak ER and DEP crossover frequencies in the literature when the medium conductivity is less than 10 mS/m. However, we can determine the membrane capacitance and conductance via the slope and intercept, respectively, of the straight line fitting of the ER peak and DEP frequency against medium conductivity data according to the linear theory only when the intercept dominates the experimental uncertainty, which occurs when the medium conductivity is less than 1 mS/m in practice.

  1. Design of experiments for amino acid extraction from tobacco leaves and their subsequent determination by capillary zone electrophoresis.

    Science.gov (United States)

    Hodek, Ondřej; Křížek, Tomáš; Coufal, Pavel; Ryšlavá, Helena

    2017-01-13

    In this study, we optimized a method for the determination of free amino acids in Nicotiana tabacum leaves. Capillary electrophoresis with contactless conductivity detector was used for the separation of 20 proteinogenic amino acids in acidic background electrolyte. Subsequently, the conditions of extraction with HCl were optimized for the highest extraction yield of the amino acids because sample treatment of plant materials brings some specific challenges. Central composite face-centered design with fractional factorial design was used in order to evaluate the significance of selected factors (HCl volume, HCl concentration, sonication, shaking) on the extraction process. In addition, the composite design helped us to find the optimal values for each factor using the response surface method. The limits of detection and limits of quantification for the 20 proteinogenic amino acids were found to be in the order of 10(-5) and 10(-4) mol l(-1), respectively. Addition of acetonitrile to the sample was tested as a method commonly used to decrease limits of detection. Ambiguous results of this experiment pointed out some features of plant extract samples, which often required specific approaches. Suitability of the method for metabolomic studies was tested by analysis of a real sample, in which all amino acids, except for L-methionine and L-cysteine, were successfully detected. The optimized extraction process together with the capillary electrophoresis method can be used for the determination of proteinogenic amino acids in plant materials. The resulting inexpensive, simple, and robust method is well suited for various metabolomic studies in plants. As such, the method represents a valuable tool for research and practical application in the fields of biology, biochemistry, and agriculture.

  2. Experiences of Health Professionals Caring for People Presenting to the Emergency Department After Taking Crystal Methamphetamine ("ICE").

    Science.gov (United States)

    Cleary, Michelle; Jackson, Debra; Woods, Cindy; Kornhaber, Rachel; Sayers, Jan; Usher, Kim

    2017-01-01

    Globally, addiction to "ICE" (crystal methamphetamine) is increasing and presents emergency health care services personnel with a number of challenges. This paper reports the first of two major themes arising from a qualitative study investigating health professionals' experiences' managing people presenting to the Emergency Department (ED) after taking "ICE." The theme "Caring for people who use 'ICE' when presenting to EDs" comprises five subthemes. These are: (a) expecting the unexpected: "they're just off their heads"; (b) complexity of care: "underlying trauma and emotional dysregulation"; (c) connecting and relationships: "engaging in a calm and helpful way"; (d) coordinating care and teamwork: "keeping them quiet and away from everybody" and (e) learning and reflection: "we need to rethink our treatment options." These findings highlight the complexity and resource-intensity associated with providing emergency care to persons affected by ICE, and the need for thoughtful strategies that can further develop the capacity and capability of health professionals to provide optimal care to people using ICE.

  3. A device for the application of uniaxial strain to single crystal samples for use in synchrotron radiation experiments

    Energy Technology Data Exchange (ETDEWEB)

    Gannon, L. [Clarendon Laboratory, University of Oxford Physics Department, Parks Road, Oxford OX1 3PU (United Kingdom); Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 ODE (United Kingdom); Bosak, A. [European Synchrotron Radiation Facility, BP 220, F-38043 Grenoble Cedex (France); Burkovsky, R. G. [European Synchrotron Radiation Facility, BP 220, F-38043 Grenoble Cedex (France); Peter the Great Saint-Petersburg Polytechnic University, 29 Politekhnicheskaya, 195251, St.-Petersburg (Russian Federation); Nisbet, G.; Hoesch, M., E-mail: Moritz.Hoesch@diamond.ac.uk [Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 ODE (United Kingdom); Petrović, A. P. [DPMC-MaNEP, Université de Genève, Quai Ernest-Ansermet 24, 1211 Genève 4 (Switzerland)

    2015-10-15

    We present the design, construction, and testing of a straining device compatible with many different synchrotron radiation techniques, in a wide range of experimental environments (including low temperature, high field and ultra-high vacuum). The device has been tested by X-ray diffraction on single crystal samples of quasi-one-dimensional Cs{sub 2}Mo{sub 6}Se{sub 6} and K{sub 2}Mo{sub 6}Se{sub 6}, in which microscopic strains up to a Δc/c = 0.12% ± 0.01% change in the c lattice parameters have been achieved. We have also used the device in an inelastic X-ray scattering experiment, to probe the strain-dependent speed of sound ν along the c axis. A reduction Δν/ν of up to −3.8% was obtained at a strain of Δc/c = 0.25% in K{sub 2}Mo{sub 6}Se{sub 6}.

  4. A novel technique for measuring stress-corrosion crack-growth rates in single-crystal experiments

    Energy Technology Data Exchange (ETDEWEB)

    Lichter, B.D. [Vanderbilt Univ., Nashville, TN (United States)]|[Delft Univ. of Technology (Netherlands); Flanagan, W.F. [Vanderbilt Univ., Nashville, TN (United States)

    1994-12-31

    Crack-growth occurs discontinuously in oriented copper-gold single-crystals during slow-strain rate experiments performed under anodic polarization in aqueous NaCl solutions. Crack advance between major crack arrests is accompanied by load-drops and current-transients which can be quantitatively related to the length of the advance as well as yielding the average instantaneous rate of advance. Two independent but self-consistent methods are used: (1) mechanical analysis of the load-drops, taking into account the elastic displacement of the load-train and of the specimen, due to both the load and the crack advance, and (2) analysis of the current-transients in which it is argued that the current is proportional to the rate of new surface production. Results show that the crack velocity is on the order of 50--400{mu}/s, depending on the environment and potential, too slow to be explained by a running brittle crack, and too fast to be explained by Faradaic dissolution.

  5. 40 YEARS OF EXPERIENCE WITH LIQUID-LIQUID EXTRACTION EQUIPMENT IN THE NUCLEAR INDUSTRY

    Energy Technology Data Exchange (ETDEWEB)

    Drain, F.; Vinoche, R.; Duhamet, J.

    2003-02-27

    Three types of liquid-liquid extraction equipment are used in industrial reprocessing plants. Each is described below, with a special focus on pulsed columns and centrifugal extractors, which have been the subject of an extensive R&D program by the French Atomic Energy Commission (CEA). Various models have been developed to simulate equipment behavior and flowsheets. The excellent results obtained during industrial operation of the UP3 and UP2-800 plants in La Hague have confirmed the validity of the choices made during the design phases and pave the way for future improvement of the reprocessing process, from a technical and a financial standpoint.

  6. Extracting Tree Height from Repeat-Pass PolInSAR Data : Experiments with JPL and ESA Airborne Systems

    Science.gov (United States)

    Lavalle, Marco; Ahmed, Razi; Neumann, Maxim; Hensley, Scott

    2013-01-01

    In this paper we present our latest developments and experiments with the random-motion-over-ground (RMoG) model used to extract canopy height and other important forest parameters from repeat-pass polarimetricinterferometric SAR (Pol-InSAR) data. More specifically, we summarize the key features of the RMoG model in contrast with the random-volume-over-ground (RVoG) model, describe in detail a possible inversion scheme for the RMoG model and illustrate the results of the RMoG inversion using airborne data collected by the Jet Propulsion Laboratory (JPL) and the European Space Agency (ESA).

  7. Extracting Tree Height from Repeat-Pass PolInSAR Data : Experiments with JPL and ESA Airborne Systems

    Science.gov (United States)

    Lavalle, Marco; Ahmed, Razi; Neumann, Maxim; Hensley, Scott

    2013-01-01

    In this paper we present our latest developments and experiments with the random-motion-over-ground (RMoG) model used to extract canopy height and other important forest parameters from repeat-pass polarimetricinterferometric SAR (Pol-InSAR) data. More specifically, we summarize the key features of the RMoG model in contrast with the random-volume-over-ground (RVoG) model, describe in detail a possible inversion scheme for the RMoG model and illustrate the results of the RMoG inversion using airborne data collected by the Jet Propulsion Laboratory (JPL) and the European Space Agency (ESA).

  8. Mesoporous silica nanoparticles synthesized from liquid crystal display manufacturing extracts as a potential candidate for a drug delivery carrier: evaluation of their safety and biocompatibility

    Directory of Open Access Journals (Sweden)

    Lin YC

    2013-10-01

    Full Text Available Yu-Chih Lin,1 Liang-Yi Lin,2 Ming-Yi Gao,3 Yi-Ping Fang31Department of Environmental Engineering and Health, Yuanpei University, 2Institute of Environmental Engineering, National Chiao Tung University, 3Department of Biotechnology, Yuanpei University, Hsinchu, TaiwanAbstract: Mesoporous silica nanoparticles (MSNs were synthesized as a promising drug delivery carrier due to the large surface area and porous characteristics. Our previous study successfully recycled wastes from the liquid crystal display (LCD industry as the silica precursor. In this study, we substantiated the possibility of applying this material as a drug carrier. MSNs synthesized from the extraction of wastes from the manufacture of LCD panels were characterized as having an average diameter of 100 nm, a surface area of 788 m2/g, a uniform pore size distribution of 3.8 nm, and a pore volume of up to 1.04 cm3/g. Methotrexate and camptothecin were entrapped in MSNs at about 33.88% and 75.12%, respectively. The cell viability assay demonstrated that MSNs at 1 µg/mL had no significant influence on human lung fibroblast (WI-38 cells or ovarian cancer (ES-2 cells. A lactate dehydrogenase assay also indicated no inflammation occurred. Moreover, a hemolytic erythrocyte test indicated that the dose range of <100 µg/mL showed that 5% of erythrocytes were affected. After exposure to biofluids, the ordered structure was slightly degraded. The results revealed that MSNs synthesized from extraction of wastes from the manufacture of LCD panels had a good entrapment capacity for hydrophobic drugs and controllable safety conditions; they may be applied as a drug delivery carrier.Keywords: mesoporous silica nanoparticles (MSNs, waste recycle, drug delivery carrier, safety, biocompatibility

  9. Pressure-field extraction from Lagrangian flow measurements: first experiences with 4D-PTV data

    Science.gov (United States)

    Neeteson, N. J.; Bhattacharya, S.; Rival, D. E.; Michaelis, D.; Schanz, D.; Schröder, A.

    2016-06-01

    As a follow-up to a previous proof-of-principle study, a novel Lagrangian pressure-extraction technique is analytically evaluated, and experimentally validated using dense 4D-PTV data. The technique is analytically evaluated using the semi-three-dimensional Taylor-Green vortex, and it is found that the Lagrangian technique out-performs the standard Eulerian technique when Dirichlet boundary conditions are enforced. However, the Lagrangian technique produces worse estimates of the pressure field when Neumann boundary conditions are enforced on boundaries with strong pressure gradients. The technique is experimentally validated using flow data obtained for the case of a free-falling, index-matched sphere at Re=2100. The experimental data were collected using a four-camera particle tracking velocimetry measurement system, and processed using 4D-PTV. The pressure field is then extracted using both the Eulerian and Lagrangian techniques, and the resulting pressure fields are compared. Qualitatively, the pressure fields agree; however, quantitative differences are found with respect to the magnitude of the pressure minima on the side of the sphere. Finally, the pressure-drag coefficient is estimated using each technique, and the two techniques are found to be in very close agreement. A comparison to a reference value from literature confirms that the drag coefficient estimates are reasonable, demonstrating the validity of the technique.

  10. Using a Sequence of Experiments with Turmeric Pigments from Food to Teach Extraction, Distillation, and Thin-Layer Chromatography to Introductory Organic Chemistry Students

    Science.gov (United States)

    da S. F. Fagundes, Thayssa; Dutra, Karen Danielle B.; Ribeiro, Carlos Magno R.; de A. Epifanio, Rosa^ngela; Valverde, Alessandra L.

    2016-01-01

    This experiment encourages students to use deductive reasoning skills to understand the correlation between different techniques used in a chemistry laboratory and to extract and analyze curcuminoids using natural products and processed food from a grocery store. Turmeric pigments were used to teach continuous or discontinuous extraction, vacuum…

  11. Using a Sequence of Experiments with Turmeric Pigments from Food to Teach Extraction, Distillation, and Thin-Layer Chromatography to Introductory Organic Chemistry Students

    Science.gov (United States)

    da S. F. Fagundes, Thayssa; Dutra, Karen Danielle B.; Ribeiro, Carlos Magno R.; de A. Epifanio, Rosa^ngela; Valverde, Alessandra L.

    2016-01-01

    This experiment encourages students to use deductive reasoning skills to understand the correlation between different techniques used in a chemistry laboratory and to extract and analyze curcuminoids using natural products and processed food from a grocery store. Turmeric pigments were used to teach continuous or discontinuous extraction, vacuum…

  12. Dynamic Crystallization Experiments Using Conventional and Solar Furnace Techniques--implications For The Formation of Refractory Forsterite In Chondrites

    Science.gov (United States)

    Pack, A.; Sauerborn, M.; Klerner, S.; Palme, H.; Neumann, A.; Seboldt, W.

    A distinct generation of forsteritic olivine (Mg2SiO4) grains (RF) with unusually high concentrations of refractory components including CaO (0.7 wt.%), Al2O3 (0.4 wt.%), V, Sc, and REEs occurs in unequilibrated chondrites, including ordinary, carbonaceous, and the highly oxidized Rumurutiites. Contents of siderophile elements like FeO (1 wt.%), Ni, or Mn are extremly low in RF. It is inferred that formation of RF pre-dates the formation of chondrules and matrix as well as formation of the different types of parent bodies (CCs, OCs, oxidized R-chondrites). Hence, RF can help us to better understand the processes in the early stage of the solar system in the time between formation of CAIs and Si,Mg-chondrules. However, formation of RF is not well understood. Crystallization of RF in chon- drules requires chondrule melts with ca. 20 wt.% CaO. Most chondrules have typically <4 wt.% CaO (max. ca. 10 wt.% CaO). We have conducted dynamic crystallization experiments using a conventional furnace (1.5...1000 K·min-1) and the DLR solar furnace (approx. 100000 K·min-1) in order to test if rapid cooling of a chondrule- like melt would produce high CaO in RF. We demostrate that Ca-partitioning between olivine and silicate melt is only weakly influenced by rapid cooling even at extremly high cooling rates in the range of 105 K·min-1 as obtained in the solar furnace ex- periments. At a bulk composition of the starting melt of 7.5 wt.% CaO, no deviation from equilibrium fractionation was observed (T/t = 1.5 . . . 105 K·min-1). At a ol/melt bulk content of 17.5 wt.% CaO, in increase in DCa of approximately 10...20% was observed. Chondrules with CaO contents in the range of 10 wt.% (upper limit of CaO in chondrules) thus cannot be regarded to be the host of RF. Hence, there must have been an early generation of extremly CaO-rich chondrules (20 wt.% CaO). Alternatively, RF may have formed by other processes, e. g. direct condensation from the solar nebula.

  13. Nursing experience of postoperative choledochoscopic stone extraction%术后胆道镜取石的护理

    Institute of Scientific and Technical Information of China (English)

    林秀云; 刘鄂长; 苏连珠; 蔡金艳

    2008-01-01

    目的 探讨术后胆道镜取石的护理经验.方法 回顾性分析237例(384例次)术后胆道镜取石的临床护理资料.结果 术后胆道镜取石结石完全取净率达90.3%,并发症均不严重.结论 针对术后胆道镜取石的一系列护理措施.有助于手术的成功开展.%Objective To explore the nursing experience of postoperative choledochoscopic stone extraction.Methods Retrospectively analysed 384 cases with postoperative choledochoscopic stone extraction. Results The rate of complete stone clearance is 90.3%in postoperative choledochoscopic stone extracdon.There is no serious complications taken place.Conclusion The nursing helps to complete the postoperative choledochoscopic stone extraction successfully.

  14. Tracking Simulation of Third-Integer Resonant Extraction for Fermilab's Mu2e Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Park, Chong Shik [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Amundson, James [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Michelotti, Leo [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

    2015-02-13

    The Mu2e experiment at Fermilab requires acceleration and transport of intense proton beams in order to deliver stable, uniform particle spills to the production target. To meet the experimental requirement, particles will be extracted slowly from the Delivery Ring to the external beamline. Using Synergia2, we have performed multi-particle tracking simulations of third-integer resonant extraction in the Delivery Ring, including space charge effects, physical beamline elements, and apertures. A piecewise linear ramp profile of tune quadrupoles was used to maintain a constant averaged spill rate throughout extraction. To study and minimize beam losses, we implemented and introduced a number of features, beamline element apertures, and septum plane alignments. Additionally, the RF Knockout (RFKO) technique, which excites particles transversely, is employed for spill regulation. Combined with a feedback system, it assists in fine-tuning spill uniformity. Simulation studies were carried out to optimize the RFKO feedback scheme, which will be helpful in designing the final spill regulation system.

  15. Tracking Simulation of Third-Integer Resonant Extraction for Fermilab's Mu2e Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Park, Chong Shik [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Amundson, James [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Michelotti, Leo [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

    2015-02-13

    The Mu2e experiment at Fermilab requires acceleration and transport of intense proton beams in order to deliver stable, uniform particle spills to the production target. To meet the experimental requirement, particles will be extracted slowly from the Delivery Ring to the external beamline. Using Synergia2, we have performed multi-particle tracking simulations of third-integer resonant extraction in the Delivery Ring, including space charge effects, physical beamline elements, and apertures. A piecewise linear ramp profile of tune quadrupoles was used to maintain a constant averaged spill rate throughout extraction. To study and minimize beam losses, we implemented and introduced a number of features, beamline element apertures, and septum plane alignments. Additionally, the RF Knockout (RFKO) technique, which excites particles transversely, is employed for spill regulation. Combined with a feedback system, it assists in fine-tuning spill uniformity. Simulation studies were carried out to optimize the RFKO feedback scheme, which will be helpful in designing the final spill regulation system.

  16. QCD Precision Measurements and Structure Function Extraction at a High Statistics, High Energy Neutrino Scattering Experiment: NuSOnG

    Energy Technology Data Exchange (ETDEWEB)

    Adams, T.; /Florida State U.; Batra, P.; /Columbia U.; Bugel, Leonard G.; /Columbia U.; Camilleri, Leslie Loris; /Columbia U.; Conrad, Janet Marie; /MIT; de Gouvea, A.; /Northwestern U.; Fisher, Peter H.; /MIT; Formaggio, Joseph Angelo; /MIT; Jenkins, J.; /Northwestern U.; Karagiorgi, Georgia S.; /MIT; Kobilarcik, T.R.; /Fermilab /Texas U.

    2009-06-01

    We extend the physics case for a new high-energy, ultra-high statistics neutrino scattering experiment, NuSOnG (Neutrino Scattering On Glass) to address a variety of issues including precision QCD measurements, extraction of structure functions, and the derived Parton Distribution Functions (PDFs). This experiment uses a Tevatron-based neutrino beam to obtain a sample of Deep Inelastic Scattering (DIS) events which is over two orders of magnitude larger than past samples. We outline an innovative method for fitting the structure functions using a parameterized energy shift which yields reduced systematic uncertainties. High statistics measurements, in combination with improved systematics, will enable NuSOnG to perform discerning tests of fundamental Standard Model parameters as we search for deviations which may hint of 'Beyond the Standard Model' physics.

  17. QCD Precision Measurements and Structure Function Extraction at a High Statistics, High Energy Neutrino Scattering Experiment: NuSOnG

    CERN Document Server

    Adams, T; Bugel, L; Camilleri, L; Conrad, J M; De Gouvêa, A; Fisher, P H; Formaggio, J A; Jenkins, J; Karagiorgi, G; Kobilarcik, T R; Kopp, S; Kyle, G; Loinaz, W A; Mason, D A; Milner, R; Moore, R; Morfín, J G; Nakamura, M; Naples, D; Nienaber, P; Olness, F I; Owens, J F; Pate, S F; Pronin, A; Seligman, W G; Shaevitz, M H; Schellman, H; Schienbein, I; Syphers, M J; Tait, T M P; Takeuchi, T; Tan, C Y; Van de Water, R G; Yamamoto, R K; Yu, J Y

    2009-01-01

    We extend the physics case for a new high-energy, ultra-high statistics neutrino scattering experiment, NuSOnG (Neutrino Scattering On Glass) to address a variety of issues including precision QCD measurements, extraction of structure functions, and the derived Parton Distribution Functions (PDFs). This experiment uses a Tevatron-based neutrino beam to obtain a sample of Deep Inelastic Scattering (DIS) events which is over two orders of magnitude larger than past samples. We outline an innovative method for fitting the structure functions using a parameterized energy shift which yields reduced systematic uncertainties. High statistics measurements, in combination with improved systematics, will enable NuSOnG to perform discerning tests of fundamental Standard Model parameters as we search for deviations which may hint of "Beyond the Standard Model" physics.

  18. Analysis of the light-extraction efficiency of SiC substrate-based flip-chip vertical light-emitting diodes with embedded photonic crystals

    Science.gov (United States)

    Liu, Meng; Li, Kang; Kong, Fan-min; Zhao, Jia; Zhao, Shu-long; Meng, Hao-tian

    2016-11-01

    To improve the light-extraction efficiency (LEE) of flip-chip vertical light-emitting diodes (LEDs) grown on silicon carbide (SiC) substrate, embedded photonic crystals (PhCs) were alternatively introduced into the n-GaN layer of LEDs, since etching of the SiC substrate was very difficult. The finite-difference time-domain (FDTD) method was employed to investigate the combination effects of the micro-cavity and the embedded PhCs. The influences of the PhCs configurations on the LEE of LEDs were also examined to get an optimal structure. With the optimized parameters, about 20% enhancement of LEE was achieved comparing to planar SiC substrate-based flip-chip vertical LEDs. The LEE of conventional surface PhCs LEDs and double layer PhCs LEDs were also investigated for comparison. The results indicated that LEDs with carefully designed embedded PhCs could provide more LEE than surface PhCs LEDs. The structures proposed here offered scopes for the design of high-efficiency, high-power LEDs.

  19. β-Keto-enol Tethered Pyridine and Thiophene: Synthesis, Crystal Structure Determination and Its Organic Immobilization on Silica for Efficient Solid-Liquid Extraction of Heavy Metals.

    Science.gov (United States)

    Radi, Smaail; Tighadouini, Said; Bacquet, Maryse; Degoutin, Stephanie; Dacquin, Jean-Philippe; Eddike, Driss; Tillard, Monique; Mabkhot, Yahia N

    2016-07-07

    Molecules bearing β-keto-enol functionality are potential candidates for coordination chemistry. Reported herein is the first synthesis and use of a novel designed ligand based on β-keto-enol group embedded with pyridine and thiophene moieties. The product was prepared in a one-step procedure by mixed Claisen condensation and was characterized by EA, m/z, FT-IR, (¹H, (13)C) NMR and single-crystal X-ray diffraction analysis. The new structure was grafted onto silica particles to afford a chelating matrix which was well-characterized by EA, FT-IR, solid-state (13)C-NMR, BET, BJH, SEM and TGA. The newly prepared organic-inorganic material was used as an adsorbent for efficient solid-phase extraction (SPE) of Cu(II), Zn(II), Cd(II) and Pb(II) from aqueous solutions and showed a capture capacity of 104.12 mg·g(-1), 98.90 mg·g(-1), 72.02 mg·g(-1), and 65.54 mg·g(-1), respectively. The adsorption capacity was investigated, in a batch method, using time of contact, pH, initial concentration, kinetics (Langmuir and Freundlich models), and thermodynamic parameters (ΔG°, ΔH° and ΔS°) of the system effects.

  20. Trace element distribution in geological crystals

    Energy Technology Data Exchange (ETDEWEB)

    Den Besten, J.L.; Jamieson, D.N.; Weiser, P.S. [Melbourne Univ., Parkville, VIC (Australia). School of Physics

    1996-12-31

    Channelling is a useful microprobe technique for determining the structure of crystals, but until now has not been performed on geological crystals. The composition has been investigated rather than the structure, which can further explain the origin of the crystal and provide useful information on the substitutionality of trace elements. This may then lead to applications of extraction of valuable metals and semiconductor electronics. Natural crystals of pyrite, FeS{sub 2}, which contains a substantial concentration of gold were channeled and examined to identify the channel axis orientation. Rutherford Backscattering (RBS) and Particle Induced X-Ray Emission (PIXE) spectra using MeV ions were obtained in the experiment to provide a comparison of lattice and non-lattice trace elements. 3 figs.

  1. Application of PbWO{sub 4} crystal scintillators in experiment to search for 2{beta} decay of {sup 116}Cd

    Energy Technology Data Exchange (ETDEWEB)

    Danevich, F.A. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine)]. E-mail: danevich@kinr.kiev.ua; Georgadze, A.Sh. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine); Kobychev, V.V. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine); Kropivyansky, B.N. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine); Nagorny, S.S. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine); Nikolaiko, A.S. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine); Poda, D.V. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine); Tretyak, V.I. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine); Vyshnevskyi, I.M. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine); Yurchenko, S.S. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine); Grinyov, B.V. [Institute for Scintillation Materials, 61001 Kharkov (Ukraine); Nagornaya, L.L. [Institute for Scintillation Materials, 61001 Kharkov (Ukraine); Pirogov, E.N. [Institute for Scintillation Materials, 61001 Kharkov (Ukraine); Ryzhikov, V.D. [Institute for Scintillation Materials, 61001 Kharkov (Ukraine); Brudanin, V.B. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Vylov, Ts. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Fedorov, A. [Institute for Nuclear Problems, 220050 Minsk (Belarus); Korzhik, M. [Institute for Nuclear Problems, 220050 Minsk (Belarus); Lobko, A. [Institute for Nuclear Problems, 220050 Minsk (Belarus); Missevitch, O. [Institute for Nuclear Problems, 220050 Minsk (Belarus)

    2006-01-01

    Lead tungstate (PbWO{sub 4}) crystal scintillators are discussed as an active shield and light guides in {sup 116}Cd double-beta decay experiment with Cadmium tungstate (CdWO{sub 4}) scintillators. Scintillation properties and radioactive contamination of PbWO{sub 4} scintillators were investigated. Energy resolution of CdWO{sub 4} detector, coupled to PbWO{sub 4} light guide, was tested. Efficiency of PbWO{sub 4}-based active shield to suppress background from the internal contamination of PbWO{sub 4} crystals, as well as possible contribution from radioactivity of copper shield and phototubes were calculated. Using of lead tungstate crystal scintillators as high-efficiency 4{pi} active shield could allow to build sensitive 2{beta} experiment (T{sub 1/2}{sup 0{nu}}{sup 2{beta}}{approx}10{sup 26}yr) to search for 0{nu}2{beta} decay of {sup 116}Cd with {sup 116}CdWO{sub 4} crystal scintillators.

  2. Viscosity measurements of crystallizing andesite from Tungurahua volcano (Ecuador)

    Science.gov (United States)

    Cimarelli, Corrado; deBiasi, Lea; Hanson, Jonathan B.; Lavallée, Yan; Arzilli, Fabio; Dingwell, Donald B.

    2015-01-01

    Abstract Viscosity has been determined during isothermal crystallization of an andesite from Tungurahua volcano (Ecuador). Viscosity was continuously recorded using the concentric cylinder method and employing a Pt‐sheathed alumina spindle at 1 bar and from 1400°C to subliquidus temperatures to track rheological changes during crystallization. The disposable spindle was not extracted from the sample but rather left in the sample during quenching thus preserving an undisturbed textural configuration of the crystals. The inspection of products quenched during the crystallization process reveals evidence for heterogeneous crystal nucleation at the spindle and near the crucible wall, as well as crystal alignment in the flow field. At the end of the crystallization, defined when viscosity is constant, plagioclase is homogeneously distributed throughout the crucible (with the single exception of experiment performed at the lowest temperature). In this experiments, the crystallization kinetics appear to be strongly affected by the stirring conditions of the viscosity determinations. A TTT (Time‐Temperature‐Transformation) diagram illustrating the crystallization “nose” for this andesite under stirring conditions and at ambient pressure has been constructed. We further note that at a given crystal content and distribution, the high aspect ratio of the acicular plagioclase yields a shear‐thinning rheology at crystal contents as low as 13 vol %, and that the relative viscosity is higher than predicted from existing viscosity models. These viscosity experiments hold the potential for delivering insights into the relative influences of the cooling path, undercooling, and deformation on crystallization kinetics and resultant crystal morphologies, as well as their impact on magmatic viscosity. PMID:27656114

  3. Viscosity measurements of crystallizing andesite from Tungurahua volcano (Ecuador).

    Science.gov (United States)

    Chevrel, Magdalena Oryaëlle; Cimarelli, Corrado; deBiasi, Lea; Hanson, Jonathan B; Lavallée, Yan; Arzilli, Fabio; Dingwell, Donald B

    2015-03-01

    Viscosity has been determined during isothermal crystallization of an andesite from Tungurahua volcano (Ecuador). Viscosity was continuously recorded using the concentric cylinder method and employing a Pt-sheathed alumina spindle at 1 bar and from 1400°C to subliquidus temperatures to track rheological changes during crystallization. The disposable spindle was not extracted from the sample but rather left in the sample during quenching thus preserving an undisturbed textural configuration of the crystals. The inspection of products quenched during the crystallization process reveals evidence for heterogeneous crystal nucleation at the spindle and near the crucible wall, as well as crystal alignment in the flow field. At the end of the crystallization, defined when viscosity is constant, plagioclase is homogeneously distributed throughout the crucible (with the single exception of experiment performed at the lowest temperature). In this experiments, the crystallization kinetics appear to be strongly affected by the stirring conditions of the viscosity determinations. A TTT (Time-Temperature-Transformation) diagram illustrating the crystallization "nose" for this andesite under stirring conditions and at ambient pressure has been constructed. We further note that at a given crystal content and distribution, the high aspect ratio of the acicular plagioclase yields a shear-thinning rheology at crystal contents as low as 13 vol %, and that the relative viscosity is higher than predicted from existing viscosity models. These viscosity experiments hold the potential for delivering insights into the relative influences of the cooling path, undercooling, and deformation on crystallization kinetics and resultant crystal morphologies, as well as their impact on magmatic viscosity.

  4. Extracting the Electron-Ion Temperature Relaxation Rate from Ion Stopping Experiments

    Science.gov (United States)

    Grabowski, Paul E.; Frenje, Johan A.; Benedict, Lorin X.

    2016-10-01

    Direct measurement of i-e equilibration rates at ICF-relevant conditions is a big challenge, as it is difficult to differentiate from other sinks and sources of energy, such as heat conduction and pdV work. Another method is to use information from ion stopping experiments. Such experiments at the OMEGA laser have made precision energy loss measurements of fusion products at these conditions. Combined with the multimonochromatic x-ray imager technique, which gives temporally and spatially resolved electron temperature and density, we have a robust stopping experiment. We propose to use such stopping measurements to assess the i-e temperature relaxation rate, since both processes involve energy exchange between electrons and ions. We require that the fusion products are 1) much faster than the thermal ions so that i-i collisions are negligible compared to i-e collisions and 2) slower than the thermal electrons so that the stopping obeys a linear friction law. Then the Coulomb logarithms associated with ion stopping and i-e temperature relaxation rate are identical and a measurement of the former provides the latter. Prepared by LLNL under Contract DE-AC52-07NA27344.

  5. Body Hair Transplant by Follicular Unit Extraction: My Experience With 122 Patients

    Science.gov (United States)

    Umar, Sanusi

    2016-01-01

    Background Body hair shafts from the beard, trunk, and extremities can be used to treat baldness when patients have inadequate amounts of scalp donor hair, but reports in the literature concerning use of body hair to treat baldness are confined to case reports. Objectives This study aimed to assess the outcome of body hair transplanted to bald areas of the scalp in selected patients. Methods From 2005 through 2011, 122 patients preselected for adequate body hair had donor hair transplanted from the beard, trunk, and the extremities to the scalp by follicular unit extraction (FUE) by the author at a single center. All patients were emailed surveys to assess surgical outcomes and overall satisfaction. Results Seventy-nine patients (64.8%) responded with a mean time of 2.9 years between date of last surgery and time of survey. Patients were generally very satisfied with results of their procedure, giving mean scores of at least a 7.8 on a Likert-like scale of 0 to 10 for their healing status, hair growth in recipient areas, and overall satisfaction with their surgeries. These scores were comparable to mean scores provided by patients whose transplants included scalp donor sources. Conclusions FUE using body hair can be an effective hair transplantation method for a select patient population of hirsute individuals who suffer from severe baldness or have inadequate scalp donor reserve. Level of Evidence: 4 Therapeutic PMID:27241361

  6. Noble Gas Diffusion Mechanism in Lunar Soil Simulant Grains: Results from 4He+ Implantation and Extraction Experiments

    Institute of Scientific and Technical Information of China (English)

    Xiaohui Fu; Yongliao Zou; Yongchun Zheng; Huaiyu He; Ziyuan Ouyang

    2011-01-01

    Experiments on ion implantation were performed in order to better characterize diffusion of noble gases in lunar soil.4He+ at 50 keV with 5×1016 ions/cm2 was implanted into lunar simulants and crystal ilmenite.Helium in the samples was released by stepwise heating experiments.Based on the data,we calculated the helium diffusion coefficient and activation energy.Lunar simulants display similar 4He release patterns in curve shape as lunar soil,but release temperatures are a little lower.This is probably a consequence of long-term diffusion after implantation in lunar soil grains.Variation of activation energy was identified in the Arrhenius plots of lunar simulants and Panzhihua (攀枝花) ilmenite.We conclude that noble gas release in lunar soil cannot be described as simple thermally activated volume diffusion.Variation of diffusion parameters could be attributed to physical transformation during high temperature.Radiation damage probably impedes helium diffusion.However,bubble radius growth during heating does not correlate with activation energy variation.Activation energy of Panzhihua ilmenite is 57.935 kJ/mol.The experimental results confirm that ilmenite is more retentive for noble gas than other lunar materials.

  7. Stig Sundell at the bent crystal X-ray spectrometer for the X-ray shift experiment.

    CERN Multimedia

    1976-01-01

    The bent crystal X-ray spectrometer is being used to measure small shifts in the frequencies of X-rays emitted from the lower electron energy levels, in order to learn about the size of the nuclei concerned

  8. Technology for Obtaining Large Size Complex Oxide Crystals for Experiments on Muon-Electron Conversion Registration in High Energy Physics

    Directory of Open Access Journals (Sweden)

    Gerasymov, Ya.

    2014-11-01

    Full Text Available Technological approaches for qualitative large size scintillation crystals growing based on rare-earth silicates are proposed. A method of iridium crucibles charging using eutectic phase instead of a oxyorthosilicate was developed.

  9. On the Lower Limit of Chondrule Cooling Rates: The Significance of Iron Loss in Dynamic Crystallization Experiments

    Science.gov (United States)

    Paque, Julie M.; Connolly, Harold C., Jr.; Lofgren, Gary E.

    1998-01-01

    It is unlikely that the presence of chondrules, and thus their formation, within the protoplanetary nebula would be predicted if it were not for their ubiquitous presence in most chondritic meteorites. The study of these enigmatic, igneous objects has a direct influence on how meteoritic and solar system researchers model the processes operating and the materials present within our protoplanetary nebula. Key to understanding chondrule formation is a determination of constraints on their thermal histories. The three important variables in this history are their peak melting temperatures, the duration of their melting at peak temperatures, and the rate at which these object cool. Although these three variables are interdependent, it is cooling rate that provides the most powerful constraint. Cooling rate has a direct affect on the development of both crystal morphology and the elemental distributions within these grains. To date, experiments have indicated that chondrule cooling rates are in the range of 10's to 100's of degrees per hour for porphyritic chondrules (the most abundant type). The cooling rate for radial and barred chondrules is thought to be more rapid. To generate these cooling rates (rapid relative to the cooling of the nebula as a whole, but slow compared to simple black body radiation) the environment of chondrule formation must have been localized, and the abundance of solid materials must have been greatly enhanced above a gas of solar composition. Thus accurate determinations of chondrule cooling rates is critical in understanding both their formation and the nebular environment in which they formed. In a quest to more accurately determine the lower limit on cooling rates and to determine in more detail the effects of Fe loss from a molten sample to Pt wire loops, Weinbruch et al. have explored this issue experimentally and reevaluated the findings of Radomsky and Hewins in light of their new results. The basic conclusions of their paper are an

  10. Organization of the production of 100 tons of lead tungstate crystals for the CMS experiment at CERN

    CERN Document Server

    Lecoq, Paul

    2004-01-01

    The CMS collaboration at CERN has undertaken at the end of 1994 an ambitious R&D program on Lead Tugstate scintillating crystals for its electromagnetic calorimeter. All the parameters of this crystal have been extensively studied in order to optimize its performances in the context of the Large Hadron Collider. Full size crystals (23 cm in length, up to 2.5 multiplied by 2.5 cm**2 in section) with the desired trapezoidal geometry can now be grown and mechanically processed with a yield in excess of 80%. A thorough investigation of the raw material preparation and of the growing conditions has led to a significant improvement in the optical transparency and in the light yield of the crystals. A detailed understanding of the light emission mechanism was 1995. A systematic analysis of the parameters influencing the structural quality of the crystals was at the origin of a considerable improvement of the radiation hardness of full size crystals. All these progress will be illustrated by results of measuremen...

  11. Fragipan Horizon Fragmentation in Slaking Experiments with Amendment Materials and Ryegrass Root Tissue Extracts

    Directory of Open Access Journals (Sweden)

    A. D. Karathanasis

    2014-01-01

    Full Text Available Slaking experiments were conducted of fragipan clods immersed in solutions of poultry manure, aerobically digested biosolid waste (ADB, fluidized bed combustion byproduct (FBC, D-H2O, CaCO3, NaF, Na-hexa-metaphosphate, and ryegrass root biomass. The fragipan clods were sampled from the Btx horizon of an Oxyaquic Fragiudalf in Kentucky. Wet sieving aggregate analysis showed significantly better fragmentation in the NaF, Na-hexa-metaphosphate, and ryegrass root solutions with a mean weight diameter range of 15.5–18.8 mm compared to the 44.2–47.9 mm of the poultry manure, ADB, and FBC treatments. Dissolved Si, Al, Fe, and Mn levels released in solution were ambiguous. The poor efficiency of the poultry manure, ADB, and FBC treatments was attributed to their high ionic strength, while the high efficiency of the NaF, Na-hexa-metaphosphate, and rye grass root solutions to their high sodium soluble ratio (SSR. A slaking mechanism is proposed suggesting that aqueous solutions with high SSR penetrate faster into the fragipan capillaries and generate the critical swelling pressure and shearing stress required to rupture the fragipan into several fragments. Additional fragmentation occurs in a followup stage during which potential Si, Al, Fe, and Mn binding agents may be released into solution. Field experiments testing these findings are in progress.

  12. Understanding internal backgrounds in NaI(Tl) crystals toward a 200 kg array for the KIMS-NaI experiment

    Energy Technology Data Exchange (ETDEWEB)

    Adhikari, P.; Adhikari, G.; Oh, S.Y. [Sejong University, Department of Physics, Seoul (Korea, Republic of); Choi, S.; Joo, H.W.; Kim, K.W.; Kim, S.K. [Seoul National University, Department of Physics and Astronomy, Seoul (Korea, Republic of); Ha, C.; Jeon, E.J.; Kang, W.G.; Kim, H.O.; Kim, N.Y.; Lee, H.S.; Lee, J.H.; Lee, M.H.; Leonard, D.S.; Li, J.; Olsen, S.L.; Park, H.K.; Park, K.S.; So, J.H.; Yoon, Y.S. [Institute for Basic Science, Center for Underground Physics, Daejeon (Korea, Republic of); Hahn, I.S. [Ewha Womans University, Department of Science Education, Seoul (Korea, Republic of); Kim, H.J. [Kyungpook National University, Department of Physics, Daegu (Korea, Republic of); Kim, Y.D. [Sejong University, Department of Physics, Seoul (Korea, Republic of); Institute for Basic Science, Center for Underground Physics, Daejeon (Korea, Republic of); Kim, Y.H. [Institute for Basic Science, Center for Underground Physics, Daejeon (Korea, Republic of); Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of); Park, H.S. [Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of)

    2016-04-15

    The Korea Invisible Mass Search (KIMS) collaboration has developed low-background NaI(Tl) crystals that are suitable for the direct detection of WIMP dark matter. Building on experience accumulated during the KIMS-CsI programs, the KIMS-NaI experiment will consist of a 200 kg NaI(Tl) crystal array surrounded by layers of shielding structures and will be operated at the Yangyang underground laboratory. The goal is to provide an unambiguous test of the DAMA/LIBRA annual modulation signature. Measurements of six prototype crystals show progress in the reduction of internal contamination from radioisotopes. Based on our understanding of these measurements, we expect to achieve a background level in the final detector configuration that is less than 1 count/day/keV/kg for recoil energies around 2 keV. The annual modulation sensitivity for the KIMS-NaI experiment shows that an unambiguous 7σ test of the DAMA/LIBRA signature would be possible with a 600 kg year exposure with this system. (orig.)

  13. Understanding internal backgrounds of NaI(Tl) crystals toward a 200~kg array for the KIMS-NaI experiment

    CERN Document Server

    Adhikari, P; Choi, S; Ha, C; Hahn, I S; Jeon, E J; Joo, H W; Kang, W G; Kim, H J; Kim, H O; Kim, K W; Kim, N Y; Kim, S K; Kim, Y D; Kim, Y H; Lee, H S; Lee, J H; Lee, M H; Leonard, D S; Li, J; Oh, S Y; Olsen, S L; Park, H K; Park, H S; Park, K S; So, J H; Yoon, Y S

    2015-01-01

    The Korea Invisible Mass Search (KIMS) collaboration has developed low-background NaI(Tl) crystals that are suitable for the direct detection of WIMP dark matter. With experience built on the KIMS-CsI programs, the KIMS-NaI experiment will consist of a 200~kg NaI(Tl) crystal array surrounded by layers of shielding structures and will be operated at the Yangyang underground laboratory. The goal is to provide an unambiguous test of the DAMA/LIBRA's annual modulation signature. Measurements of six prototype crystals show progress in the reduction of internal contaminations of radioisotopes. Based on our understanding of these measurements, we expect to achieve a background level in the final detector configuration that is less than 1~count/day/keV/kg for recoil energies around 2~keV. The annual modulation sensitivity for the KIMS-NaI experiment shows that an unambiguous 7$\\sigma$ test of the DAMA/LIBRA signature would be possible with a 600~kg$\\cdot$year exposure with this system.

  14. A study of pumps for the Hot Dry Rock Geothermal Energy extraction experiment (LTFT (Long Term Flow Test))

    Energy Technology Data Exchange (ETDEWEB)

    Tatro, C.A.

    1986-10-01

    A set of specifications for the hot dry rock (HDR) Phase II circulation pumping system is developed from a review of basic fluid pumping mechanics, a technical history of the HDR Phase I and Phase II pumping systems, a presentation of the results from experiment 2067 (the Initial Closed-Loop Flow Test or ICFT), and consideration of available on-site electrical power limitations at the experiment site. For the Phase II energy extraction experiment (the Long Term Flow Test or LTFT) it is necessary to provide a continuous, low maintenance, and highly efficient pumping capability for a period of twelve months at variable flowrates up to 420 gpm and at surface injection pressures up to 5000 psi. The pumping system must successfully withstand attacks by corrosive and embrittling gases, erosive chemicals and suspended solids, and fluid pressure and temperature fluctuations. In light of presently available pumping hardware and electric power supply limitations, it is recommended that positive displacement multiplex plunger pumps, driven by variable speed control electric motors, be used to provide the necessary continuous surface injection pressures and flowrates for LTFT. The decision of whether to purchase the required circulation pumping hardware or to obtain contractor provided pumping services has not been made.

  15. Extracting Cell Stiffness from Real-Time Deformability Cytometry: Theory and Experiment.

    Science.gov (United States)

    Mietke, Alexander; Otto, Oliver; Girardo, Salvatore; Rosendahl, Philipp; Taubenberger, Anna; Golfier, Stefan; Ulbricht, Elke; Aland, Sebastian; Guck, Jochen; Fischer-Friedrich, Elisabeth

    2015-11-17

    Cell stiffness is a sensitive indicator of physiological and pathological changes in cells, with many potential applications in biology and medicine. A new method, real-time deformability cytometry, probes cell stiffness at high throughput by exposing cells to a shear flow in a microfluidic channel, allowing for mechanical phenotyping based on single-cell deformability. However, observed deformations of cells in the channel not only are determined by cell stiffness, but also depend on cell size relative to channel size. Here, we disentangle mutual contributions of cell size and cell stiffness to cell deformation by a theoretical analysis in terms of hydrodynamics and linear elasticity theory. Performing real-time deformability cytometry experiments on both model spheres of known elasticity and biological cells, we demonstrate that our analytical model not only predicts deformed shapes inside the channel but also allows for quantification of cell mechanical parameters. Thereby, fast and quantitative mechanical sampling of large cell populations becomes feasible.

  16. Surrogate Seeds For Growth Of Crystals

    Science.gov (United States)

    Shlichta, Paul J.

    1989-01-01

    Larger crystals of higher quality grown. Alternative method for starting growth of crystal involves use of seed crystal of different material instead of same material as solution. Intended for growing single-crystal proteins for experiments but applicable in general to growth of crystals from solutions and to growth of semiconductor or other crystals from melts.

  17. Quartz dissolution. I - Negative crystal experiments and a rate law. II - Theory of rough and smooth surfaces

    Science.gov (United States)

    Gratz, Andrew J.; Bird, Peter

    1993-01-01

    The range of the measured quartz dissolution rates, as a function of temperature and pOH, extent of saturation, and ionic strength, is extended to cover a wider range of solution chemistries, using the negative crystal methodology of Gratz et al. (1990) to measure the dissolution rate. A simple rate law describing the quartz dissolution kinetics above the point of zero charge of quartz is derived for ionic strengths above 0.003 m. Measurements were performed on some defective crystals, and the mathematics of step motion was developed for quartz dissolution and was compared with rough-face behavior using two different models.

  18. Quantitative determination of zero-gravity effects on electronic materials processing germanium crystal growth with simultaneous interface demarcation. Experiment MA-060

    Science.gov (United States)

    Gatos, H. C.; Witt, A. F.

    1977-01-01

    Experiment MA-060 was designed to establish the crystal growth and segregation characteristics of a melt in a directional solidification configuration under near zero-g conditions. The interface demarcation technique was incorporated into the experiment since it constitutes a unique tool for recording the morphology of the growth rate throughout solidification, and for establishing an absolute time reference framework for all stages of the solidification process. An extensive study was performed of the germanium crystals grown during the Apollo-Soyuz Test Project mission. It was found that single crystal growth was achieved and that the interface demarcation functioned successfully. There was no indication that convection driven by thermal or surface tension gradients was present in the melt. The gallium segregation, in the absence of gravity, was found to be fundamentally different in its initial and its subsequent stages from that of the ground-based tests. None of the existing theoretical models for growth and segregation can account for the observed segregation behavior in the absence of gravity.

  19. Are All Obsidians Super-Heated? Insights from Observations of Crystallization Kinetics in Experiments on Glass Mountain Obsidians (Long Valley, CA)

    Science.gov (United States)

    Waters, L.; Andrews, B. J.

    2015-12-01

    The Glass Mountain obsidians (Long Valley, CA) are crystal-poor (obsidians, if the mineral assemblage is phenocrystic. Results of high-resolution SEM mapping and electron microprobe analysis of a Glass Mountain sample reveal that the obsidian is saturated in nine phases (sanidine + quartz + plagioclase + ilmenite + titanomagnetite + zircon + apatite + allanite + biotite). Sanidine (Or78-Or35) and quartz occur in the largest abundances, and plagioclase (obsidians, requires that the mechanism that produced these obsidians have an associated kinetic effect that strongly hinders nucleation. Decompression and cooling experiments, conducted in this study and from the literature, demonstrate that the simplest way to hinder nucleation is to initiate degassing or cooling from super-liquidus conditions. Therefore, the Glass Mountain obsidians were super-heated prior to crystallization, achieved either by fluid under-saturated decompression from a crystalline mush or H2O-saturated partial melting.

  20. Study of CdMoO4 crystal for a neutrinoless double beta decay experiment with 116Cd and 100Mo nuclides

    Science.gov (United States)

    Xue, Ming-Xuan; Zhang, Yun-Long; Peng, Hai-Ping; Xu, Zi-Zong; Wang, Xiao-Lian

    2017-04-01

    The scintillation properties of a CdMoO4 crystal have been investigated experimentally. The fluorescence yields and decay times measured from 22 K to 300 K demonstrate that CdMoO4 crystal is a good candidate for an absorber for a bolometer readout, for both heat and scintillation signals. The results from Monte Carlo studies, taking the backgrounds from 2ν2β of and internal trace nuclides 214Bi and 208Tl into account, show that the expected sensitivity of a CdMoO4 bolometer for neutrinoless double beta decay experiments with an exposure of 100 kg·years is one order of magnitude higher than those of the current sets of the of and Supported by National Natural Science Foundation of China (11275199)

  1. Characterization of x-ray imaging crystal spectrometer for high-resolution spatially-resolved x-ray Thomson scattering measurements in shock-compressed experiments

    Science.gov (United States)

    Lu, J.; Hill, K. W.; Bitter, M.; Pablant, N. A.; Delgado-Aparicio, L. F.; Efthimion, P. C.; Lee, H. J.; Zastrau, U.

    2017-01-01

    We have proposed, designed and built a dual-channel x-ray imaging crystal spectrometer (XICS) for spectrally- and spatially-resolved x-ray Thomson scattering (XRTS) measurements in the Matter in Extreme Conditions (MEC) end station at the Linac Coherent Light Source (LCLS). This spectrometer employs two spherically-bent germanium (Ge) 220 crystals, which are combined to form a large aperture dispersive element with a spectral bandwidth of 300 eV that enables both the elastic and inelastic x-ray scattering peaks to be simultaneously measured. The apparatus and its characterization are described. A resolving power of 1900 was demonstrated and a spatial resolution of 12 μm was achieved in calibration tests. For XRTS measurements, a narrow-bandwidth (ΔE/Ecarbon plasma produced in shock-compressed samples of different forms of carbon. Preliminary results of the scattering experiments from Pyrolytic Graphite samples that illustrate the utility of the instrument are presented.

  2. Manipulation of hadron beams with bent crystals in circular accelerators

    CERN Document Server

    Rossi, R; Redaelli, S; Scandale, W

    2016-01-01

    Over the past years the understanding and use of coherent interactions of charged particles with ordered crystal lattices has achieved excellent results. Improving collimation of hadron beams in circular accelerators, like the Large Hadron Collider (LHC) of the European Council for Nuclear Research (CERN), it is one of the possible applications. The aim of the UA9 experiment is to demonstrate the feasibility of a two-stage collimation system in the CERN-SPS : the first stage is a bent crystal oriented for an optimal channeling of the incoming halo particles; the second stage is a massive absorber. Two crystals were installed in the LHC last year and a test of crystal assisted collimation at the highest energy will be possible as early as 2015. Finally, the UA9 Collaboration is investigating extraction of particles from a circular accelerator, based on bent crystals.

  3. Experiences in managing problematic crystal methamphetamine use and associated depression in gay men and HIV positive men: in-depth interviews with general practitioners in Sydney, Australia.

    Science.gov (United States)

    Saltman, Deborah C; Newman, Christy E; Mao, Limin; Kippax, Susan C; Kidd, Michael R

    2008-08-15

    This paper describes the experiences of Australian general practitioners (GPs) in managing problematic crystal methamphetamine (crystal meth) use among two groups of male patients: gay men and HIV positive men. Semi-structured qualitative interviews with GPs with HIV medication prescribing rights were conducted in Sydney, Adelaide and a rural-coastal town in New South Wales between August and October 2006. Participants were recruited from practices with high caseloads of gay and HIV positive men. Sixteen GPs were recruited from seven practices to take part in interviews. Participants included 14 male GPs and two female GPs, and the number of years each had been working in HIV medicine ranged from two to 24. Eleven of the GPs who were based in Sydney raised the issue of problematic crystal meth use in these two patient populations. Five key themes were identified: an increasing problem; associations with depression; treatment challenges; health services and health care; workforce issues. Despite study limitations, key implications can be identified. Health practitioners may benefit from broadening their understandings of how to anticipate and respond to problematic levels of crystal meth use in their patients. Early intervention can mitigate the impact of crystal meth use on co-morbid mental illness and other health issues. Management of the complex relationships between drug use, depression, sexuality and HIV can be addressed following a 'stepped care' approach. General practice guidelines for the management of crystal meth use problems should address specific issues associated with gay men and HIV positive men. GPs and other health practitioners must appreciate drug use as a social practice in order to build trust with gay men to encourage full disclosure of drug use. Education programs should train health practitioners in these issues, and increased resourcing provided to support the often difficult task of caring for people who use crystal meth. Greater

  4. Progress on photonic crystals

    CERN Document Server

    Lecoq, P; Gundacker, S; Hillemanns, H; Jarron, P; Knapitsch, A; Leclercq, J L; Letartre, X; Meyer, T; Pauwels, K; Powolny, F; Seassal, C

    2010-01-01

    The renewal of interest for Time of Flight Positron Emission Tomography (TOF PET) has highlighted the need for increasing the light output of scintillating crystals and in particular for improving the light extraction from materials with a high index of refraction. One possible solution to overcome the problem of total internal reflection and light losses resulting from multiple bouncing within the crystal is to improve the light extraction efficiency at the crystal/photodetector interface by means of photonic crystals, i.e. media with a periodic modulation of the dielectric constant at the wavelength scale. After a short reminder of the underlying principles this contribution proposes to present the very encouraging results we have recently obtained on LYSO pixels and the perspectives on other crystals such as BGO, LuYAP and LuAG. These results confirm the impressive predictions from our previously published Monte Carlo simulations. A detailed description of the sample preparation procedure is given as well ...

  5. High-throughput crystallization screening.

    Science.gov (United States)

    Skarina, Tatiana; Xu, Xiaohui; Evdokimova, Elena; Savchenko, Alexei

    2014-01-01

    Protein structure determination by X-ray crystallography is dependent on obtaining a single protein crystal suitable for diffraction data collection. Due to this requirement, protein crystallization represents a key step in protein structure determination. The conditions for protein crystallization have to be determined empirically for each protein, making this step also a bottleneck in the structure determination process. Typical protein crystallization practice involves parallel setup and monitoring of a considerable number of individual protein crystallization experiments (also called crystallization trials). In these trials the aliquots of purified protein are mixed with a range of solutions composed of a precipitating agent, buffer, and sometimes an additive that have been previously successful in prompting protein crystallization. The individual chemical conditions in which a particular protein shows signs of crystallization are used as a starting point for further crystallization experiments. The goal is optimizing the formation of individual protein crystals of sufficient size and quality to make them suitable for diffraction data collection. Thus the composition of the primary crystallization screen is critical for successful crystallization.Systematic analysis of crystallization experiments carried out on several hundred proteins as part of large-scale structural genomics efforts allowed the optimization of the protein crystallization protocol and identification of a minimal set of 96 crystallization solutions (the "TRAP" screen) that, in our experience, led to crystallization of the maximum number of proteins.

  6. Demonstration of Crystal Structure.

    Science.gov (United States)

    Neville, Joseph P.

    1985-01-01

    Describes an experiment where equal parts of copper and aluminum are heated then cooled to show extremely large crystals. Suggestions are given for changing the orientation of crystals by varying cooling rates. Students are more receptive to concepts of microstructure after seeing this experiment. (DH)

  7. N. S. LESKOV’S NOTEBOOK WITH EXTRACTS FROM “PROLOGUE” (THE EXPERIENCE OF TEXTUAL COMMENTS

    Directory of Open Access Journals (Sweden)

    Inna N. Mineeva

    2016-03-01

    Full Text Available Thе article, for the fi rst time, provides a detailed textual commentary on N. S. Leskov’s notebook with extracts from “Prologue”. The extant literary materials include extracts and abstracts from the early printed Prologue, fi ction and historical literature of the 19th century, letters of European and Russian scholars and authors (Pushkin A., Tolstoy L., Pigault-Lebrun, Sher I., devoted to  doctrine matters and religious aspects, description and analysis of anthropologic categories. The autograph is the evidence of spiritual search and creative experiments of  the writer. In  the books the  writer found endorsement of both his own ideas, and those ones that require further inner understanding, questioning and emotional upheaval. Meanwhile, studying the history, structure and contents of  Prologue in  the 1880s, Leskov found an  exceptional existential and creative experience. The most part of  the notebook shows the writer’s learning process of various examples of repentance, atonement, a sudden rebirth of a sinner, active love, the benefi ts of obedience, the miracle of movement of a saint in space, the phenomenon of manifestation of  supernatural power and its intervention in  life of  a  man (God, the Holy Spirit, Angels, etc. While working with Prologue texts Leskov enunciated some principles of  their artistic processing  (quoting “crisis”, “turning”, unusual fragments in  the Church Slavonic language, emphasizing key situations by changing the name, specifying the narration, acronyms, graphic intonation. General trends in  understanding of  the  Prologue source (ideological, imaginative, plot-compositional, stylistic, identifi ed in the notebook, are subsequently transformed by the author in a series of “Byzantine Legends” where they receive additional semantic and functional load.

  8. Optical vortex conversion in the elliptic vortex-beam propagating orthogonally to the crystal optical axis: the experiment

    Science.gov (United States)

    Sokolenko, Bogdan; Kudryavtseva, Maria; Zinovyev, Alexey; Konovalenko, Victor; Rubass, Alex

    2012-01-01

    We have experimentally analyzed the topological reactions occurred in the elliptic vortex-beam transmitting orthogonally to the optical axis of the SiO2 crystal. We have revealed that the oscillations of the polarization state when propagating the beam are accompanied by reconstruction of the polarization singularities at the beam cross-section that, in turn, entails the reconstruction of the wavefront in each circularly polarized beam component. Both synchronic oscillations of the spin angular momentum and the sign of the vortex topological charge are expressing in a field structure as birth and annihilation of topological dipoles. Also periodical conversion of the vortex ellipticity along the crystal length z and huge splash of spin angular momentum were analysed. The run of the dislocation reactions in the beam component results in converting the sign of the topological charge in the centered optical vortex, the distance of the vortex conversion being about 0.05 of the wavelength.

  9. Ratio of the contributions real and virtual photons diffraction in thin perfect crystals. Comparison of calculation and experiment

    Science.gov (United States)

    Goponov, Yu. A.; Laktionova, S. A.; Sidnin, M. A.; Vnukov, I. E.

    2017-07-01

    To evaluate and improve the previously proposed method of calculating diffracted photon yields in thin perfect crystals, a comparison between calculated and experimental results in wide range of photons and electrons energy was carried out. It is shown that the proposed method describes all investigated experimental results for bremsstrahlung diffraction and transition radiation one with an error less than ten-fifteen percent. Consequently, the method may be used for calculation of the electron beam divergence influence on the diffracted transition radiation angular distribution.

  10. Influence of non steady gravity on natural convection during micro-gravity solidification of semiconductors. I - Time scale analysis. II - Implications for crystal growth experiments

    Science.gov (United States)

    Griffin, P. R.; Motakef, S.

    1989-01-01

    Consideration is given to the influence of temporal variations in the magnitude of gravity on natural convection during unidirectional solidification of semiconductors. It is shown that the response time to step changes in g at low Rayleigh numbers is controlled by the momentum diffusive time scale. At higher Rayleigh numbers, the response time to increases in g is reduced because of inertial effects. The degree of perturbation of flow fields by transients in the gravitational acceleration on the Space Shuttle and the Space Station is determined. The analysis is used to derive the requirements for crystal growth experiments conducted on low duration low-g vehicles. Also, the effectiveness of sounding rockets and KC-135 aircraft for microgravity experiments is examined.

  11. Influence of non steady gravity on natural convection during micro-gravity solidification of semiconductors. I - Time scale analysis. II - Implications for crystal growth experiments

    Science.gov (United States)

    Griffin, P. R.; Motakef, S.

    1989-01-01

    Consideration is given to the influence of temporal variations in the magnitude of gravity on natural convection during unidirectional solidification of semiconductors. It is shown that the response time to step changes in g at low Rayleigh numbers is controlled by the momentum diffusive time scale. At higher Rayleigh numbers, the response time to increases in g is reduced because of inertial effects. The degree of perturbation of flow fields by transients in the gravitational acceleration on the Space Shuttle and the Space Station is determined. The analysis is used to derive the requirements for crystal growth experiments conducted on low duration low-g vehicles. Also, the effectiveness of sounding rockets and KC-135 aircraft for microgravity experiments is examined.

  12. Quantum irreversible decoherence behaviour in open quantum systems with few degrees of freedom. Application to 1H NMR reversion experiments in nematic liquid crystals

    CERN Document Server

    Segnorile, H H

    2013-01-01

    An experimental study of NMR spin decoherence in nematic liquid crystals is presented. The outcome of the experiments are analyzed in the framework of a theory that considers the spins as an open quantum system coupled to a quantum molecular environment, presented by the authors recently. Decoherence dynamics can be put in evidence by means of refocusing experiments of the dipolar interactions. The experimental technique used in this work is based on the MREV8 pulse sequence. Non-idealities of the experimental setting, like external field inhomogeneity, pulse misadjustments and the presence of non-reverted spin interaction terms are analysed in detail and their effects on the observed signal decay are estimated. It is found that, though all these non-idealities could in principle affect the evolution of the spin dynamics, their influence can be mitigated and they do not present the characteristic behaviour of the irreversible spin decoherence. As unique characteristic of decoherence, the experimental results ...

  13. Partial least squares model and design of experiments toward the analysis of the metabolome of Jatropha gossypifolia leaves: Extraction and chromatographic fingerprint optimization.

    Science.gov (United States)

    Pilon, Alan Cesar; Carnevale Neto, Fausto; Freire, Rafael Teixeira; Cardoso, Patrícia; Carneiro, Renato Lajarim; Da Silva Bolzani, Vanderlan; Castro-Gamboa, Ian

    2016-03-01

    A major challenge in metabolomic studies is how to extract and analyze an entire metabolome. So far, no single method was able to clearly complete this task in an efficient and reproducible way. In this work we proposed a sequential strategy for the extraction and chromatographic separation of metabolites from leaves Jatropha gossypifolia using a design of experiments and partial least square model. The effect of 14 different solvents on extraction process was evaluated and an optimized separation condition on liquid chromatography was estimated considering mobile phase composition and analysis time. The initial conditions of extraction using methanol and separation in 30 min between 5 and 100% water/methanol (1:1 v/v) with 0.1% of acetic acid, 20 μL sample volume, 3.0 mL min(-1) flow rate and 25°C column temperature led to 107 chromatographic peaks. After the optimization strategy using i-propanol/chloroform (1:1 v/v) for extraction, linear gradient elution of 60 min between 5 and 100% water/(acetonitrile/methanol 68:32 v/v with 0.1% of acetic acid), 30 μL sample volume, 2.0 mL min(-1) flow rate, and 30°C column temperature, we detected 140 chromatographic peaks, 30.84% more peaks compared to initial method. This is a reliable strategy using a limited number of experiments for metabolomics protocols.

  14. CMS lead tungstate crystals

    CERN Multimedia

    Laurent Guiraud

    2000-01-01

    These crystals are made from lead tungstate, a crystal that is as clear as glass yet with nearly four times the density. They have been produced in Russia to be used as scintillators in the electromagnetic calorimeter on the CMS experiment, part of the LHC project at CERN. When an electron, positron or photon passes through the calorimeter it will cause a cascade of particles that will then be absorbed by these scintillating crystals, allowing the particle's energy to be measured.

  15. Design, manufacture and factory testing of the Ion Source and Extraction Power Supplies for the SPIDER experiment

    Energy Technology Data Exchange (ETDEWEB)

    Bigi, Marco, E-mail: marco.bigi@igi.cnr.it [Consorzio RFX (CNR, ENEA, INFN, Università di Padova, Acciaierie Venete SpA), Corso Stati Uniti 4, 35127 Padova (Italy); Rinaldi, Luigi [OCEM Energy Technology, Via della Solidarietà 2/1, 40056 Valsamoggia (località Crespellano), Bologna (Italy); Simon, Muriel [Fusion for Energy, Josep Pla 2, 08019 Barcelona (Spain); Sita, Luca; Taddia, Giuseppe; Carrozza, Saverino [OCEM Energy Technology, Via della Solidarietà 2/1, 40056 Valsamoggia (località Crespellano), Bologna (Italy); Decamps, Hans [ITER Organization, Route de Vinon sur Verdon, 13115 Saint Paul lez Durance (France); Luchetta, Adriano [Consorzio RFX (CNR, ENEA, INFN, Università di Padova, Acciaierie Venete SpA), Corso Stati Uniti 4, 35127 Padova (Italy); Meddour, Abdelraouf [HIMMELWERK Hoch- und Mittelfrequenzanlagen GmbH, Jopestr. 10, 72072 Tübingen (Germany); Moressa, Modesto [Consorzio RFX (CNR, ENEA, INFN, Università di Padova, Acciaierie Venete SpA), Corso Stati Uniti 4, 35127 Padova (Italy); Morri, Cristiano; Musile Tanzi, Antonio [OCEM Energy Technology, Via della Solidarietà 2/1, 40056 Valsamoggia (località Crespellano), Bologna (Italy); Recchia, Mauro [Consorzio RFX (CNR, ENEA, INFN, Università di Padova, Acciaierie Venete SpA), Corso Stati Uniti 4, 35127 Padova (Italy); Wagner, Uwe [HIMMELWERK Hoch- und Mittelfrequenzanlagen GmbH, Jopestr. 10, 72072 Tübingen (Germany); Zamengo, Andrea; Toigo, Vanni [Consorzio RFX (CNR, ENEA, INFN, Università di Padova, Acciaierie Venete SpA), Corso Stati Uniti 4, 35127 Padova (Italy)

    2015-10-15

    Highlights: • 5 MVA ion source power supplies effectively integrated in 150 m{sup 2} Faraday cage. • Load protection and performance requirements met of custom design high voltage power supplies. • 200 kW tetrode oscillator with 200 kHz frequency range successfully tested. - Abstract: The SPIDER experiment, currently under construction at the Neutral Beam Test Facility in Padua, Italy, is a full-size prototype of the ion source for the ITER Neutral Beam Injectors. The Ion Source and Extraction Power Supplies (ISEPS) for SPIDER are supplied by OCEM Energy Technology s.r.l. (OCEM) under a procurement contract with Fusion for Energy (F4E) covering also the units required for MITICA and ITER injectors. The detailed design of SPIDER ISEPS was finalized in 2011 and manufacture of most components completed by end 2013. The Factory Acceptance Tests took place early 2014. ISEPS, with an overall power rating of 5 MVA, form a heterogeneous set of items including solid state power converters and 1 MHz radiofrequency generators of 200 kW output power. The paper presents the main features of the detailed design developed by OCEM, focusing in particular on the high output voltage pulse step modulators, the high output current resonant converters, the radiofrequency generators by HIMMELWERK GmbH and the architecture and implementation of the complex control system. Details are given on non-standard factory tests verifying the insulation requirements specific to this application. Performance of ISEPS during the factory acceptance tests is described, with emphasis on demonstration of the load protection requirements, a crucial point for all neutral beam power supplies. Finally, key dates of SPIDER ISEPS installation and site testing schedule are provided.

  16. Crystals in crystals

    DEFF Research Database (Denmark)

    Christensen, Claus H.; Schmidt, I.; Carlsson, A.;

    2005-01-01

    A major factor governing the performance of catalytically active particles supported on a zeolite carrier is the degree of dispersion. It is shown that the introduction of noncrystallographic mesopores into zeolite single crystals (silicalite-1, ZSM-5) may increase the degree of particle dispersion...... of the zeolite particles, particularly after thermal treatment. When using mesoporous zeolites, the particles were evenly distributed throughout the mesopore system of the zeolitic support, even after calcination, leading to nanocrystals within mesoporous zeolite single crystals....

  17. Automation in biological crystallization

    Science.gov (United States)

    Shaw Stewart, Patrick; Mueller-Dieckmann, Jochen

    2014-01-01

    Crystallization remains the bottleneck in the crystallographic process leading from a gene to a three-dimensional model of the encoded protein or RNA. Automation of the individual steps of a crystallization experiment, from the preparation of crystallization cocktails for initial or optimization screens to the imaging of the experiments, has been the response to address this issue. Today, large high-throughput crystallization facilities, many of them open to the general user community, are capable of setting up thousands of crystallization trials per day. It is thus possible to test multiple constructs of each target for their ability to form crystals on a production-line basis. This has improved success rates and made crystallization much more convenient. High-throughput crystallization, however, cannot relieve users of the task of producing samples of high quality. Moreover, the time gained from eliminating manual preparations must now be invested in the careful evaluation of the increased number of experiments. The latter requires a sophisticated data and laboratory information-management system. A review of the current state of automation at the individual steps of crystallization with specific attention to the automation of optimization is given. PMID:24915074

  18. Automation in biological crystallization.

    Science.gov (United States)

    Stewart, Patrick Shaw; Mueller-Dieckmann, Jochen

    2014-06-01

    Crystallization remains the bottleneck in the crystallographic process leading from a gene to a three-dimensional model of the encoded protein or RNA. Automation of the individual steps of a crystallization experiment, from the preparation of crystallization cocktails for initial or optimization screens to the imaging of the experiments, has been the response to address this issue. Today, large high-throughput crystallization facilities, many of them open to the general user community, are capable of setting up thousands of crystallization trials per day. It is thus possible to test multiple constructs of each target for their ability to form crystals on a production-line basis. This has improved success rates and made crystallization much more convenient. High-throughput crystallization, however, cannot relieve users of the task of producing samples of high quality. Moreover, the time gained from eliminating manual preparations must now be invested in the careful evaluation of the increased number of experiments. The latter requires a sophisticated data and laboratory information-management system. A review of the current state of automation at the individual steps of crystallization with specific attention to the automation of optimization is given.

  19. Indentation Pileup Behavior of Ti-6Al-4V Alloy: Experiments and Nonlocal Crystal Plasticity Finite Element Simulations

    Science.gov (United States)

    Han, Fengbo; Tang, Bin; Yan, Xu; Peng, Yifei; Kou, Hongchao; Li, Jinshan; Deng, Ying; Feng, Yong

    2017-01-01

    This study reports on the indentation pileup behavior of Ti-6Al-4V alloy. Berkovich nanoindentation was performed on a specimen with equiaxed microstructure. The indented area was characterized by electron backscattered diffraction (EBSD) to obtain the indented grain orientations. Surface topographies of several indents were measured by atomic force microscopy (AFM). The pileup patterns on the indented surfaces show significant orientation dependence. Corresponding nonlocal crystal plasticity finite element (CPFE) simulations were carried out to predict the pileup patterns. Analysis of the cumulative shear strain distributions and evolutions for different slip systems around the indents found that the pileups are mainly caused by prismatic slip. The pileup patterns evolve with the loading and unloading process, and the change in pileup height due to the elastic recovery at unloading stage is significant. The density distributions of geometrically necessary dislocations (GNDs) around the indent were predicted. Simulation of nanoindentation on a tricrystal model was performed.

  20. Indentation Pileup Behavior of Ti-6Al-4V Alloy: Experiments and Nonlocal Crystal Plasticity Finite Element Simulations

    Science.gov (United States)

    Han, Fengbo; Tang, Bin; Yan, Xu; Peng, Yifei; Kou, Hongchao; Li, Jinshan; Deng, Ying; Feng, Yong

    2017-04-01

    This study reports on the indentation pileup behavior of Ti-6Al-4V alloy. Berkovich nanoindentation was performed on a specimen with equiaxed microstructure. The indented area was characterized by electron backscattered diffraction (EBSD) to obtain the indented grain orientations. Surface topographies of several indents were measured by atomic force microscopy (AFM). The pileup patterns on the indented surfaces show significant orientation dependence. Corresponding nonlocal crystal plasticity finite element (CPFE) simulations were carried out to predict the pileup patterns. Analysis of the cumulative shear strain distributions and evolutions for different slip systems around the indents found that the pileups are mainly caused by prismatic slip. The pileup patterns evolve with the loading and unloading process, and the change in pileup height due to the elastic recovery at unloading stage is significant. The density distributions of geometrically necessary dislocations (GNDs) around the indent were predicted. Simulation of nanoindentation on a tricrystal model was performed.

  1. The surface orientation dependence of the pre-exponential factors extracted from the segregation profiles of a Cu(111/110) bi-crystal

    CSIR Research Space (South Africa)

    Jafta, CJ

    2011-07-01

    Full Text Available Previous experimental investigations have only shown, without explanation, that the pre-exponential factor (D0), in the diffusion coefficient of Sb segregating in Cu, is dependent on the surface orientation of a crystal. In this study, the surface...

  2. OZSPEC-2: an improved broadband high-resolution elliptical crystal x-ray spectrometer for high-energy density physics experiments (invited).

    Science.gov (United States)

    Heeter, R F; Anderson, S G; Booth, R; Brown, G V; Emig, J; Fulkerson, S; McCarville, T; Norman, D; Schneider, M B; Young, B K F

    2008-10-01

    A novel time, space, and energy-resolved x-ray spectrometer has been developed which produces, in a single snapshot, a broadband and relatively calibrated spectrum of the x-ray emission from a high-energy density laboratory plasma. The opacity zipper spectrometer (OZSPEC-1) records a nearly continuous spectrum for x-ray energies from 240 to 5800 eV in a single shot. The second-generation OZSPEC-2, detailed in this work, records fully continuous spectra on a single shot from any two of these three bands: 270-650, 660-1580, and 1960-4720 eV. These instruments thus record thermal and line radiation from a wide range of plasmas. These instruments' single-shot bandwidth is unmatched in a time-gated spectrometer; conversely, other broadband instruments are either time-integrated (using crystals or gratings), lack spectral resolution (diode arrays), or cover a lower energy band (gratings). The OZSPECs are based on the zipper detector, a large-format (100x35 mm) gated microchannel plate detector, with spectra dispersed along the 100 mm dimension. OZSPEC-1 and -2 both use elliptically bent crystals of OHM, RAP, and/or PET. Individual spectra are gated in 100 ps. OZSPEC-2 provides one-dimensional spatial imaging with 30-50 microm resolution over a 1500 microm field of view at the source. The elliptical crystal design yields broad spectral coverage with resolution E/DeltaE>500, strong rejection of hard x-ray backgrounds, and negligible source broadening for extended sources. Near-term applications include plasma opacity measurements, detailed spectra of inertial fusion Hohlraums, and laboratory astrophysics experiments.

  3. Coherent Dynamics of Quantum Dots in Photonic-Crystal Cavities

    DEFF Research Database (Denmark)

    Madsen, Kristian Høeg

    deviations. Similar measurements on a quantum dot in a photonic-crystal cavity sow a Rabi splitting on resonance, while time-resolved measurements prove that the system is in the weak coupling regime. Whle tuning the quantum dot through resonance of the high-Q mode we observe a strong and surprisingly...... Successfully model the decay rates with a microscopic model that allows us to for the first time extract the effective phonon density of states, which we can model with bulk phonons. Studies on a quantum dot detuned from a low-Q mode of a photonic-crystal cavity show a high collection efficiency at the first......In this thesis we have performed quantum-electrodynamics experiments on quantum dots embedded in photonic-crystal cavities. We perform a quantitative comparison of the decay dynamics and emission spectra of quantum dots embedded in a micropillar cavity and a photonic-crystal cavity. The light...

  4. Vortex beam generation and other advanced optics experiments reproduced with a twisted-nematic liquid-crystal display with limited phase modulation

    Science.gov (United States)

    Cofré, Aaron; García-Martínez, Pascuala; Vargas, Asticio; Moreno, Ignacio

    2017-01-01

    In this work we propose the use of twisted-nematic liquid-crystal spatial light modulators (TN-LC-SLM) as a useful tool for training students in the manipulation of light beams with phase-only masks. In particular, we focus the work on the realization of phase-only gratings and phase-only spiral phases for the generation of vortex beams, beams carrying orbital angular momentum (OAM). Despite the extensive activity in this field, its experimental implementation for educational purposes is limited because it requires the use of very expensive high-resolution liquid-crystal on silicon (LCOS) SLMs. Here, we show that a low-cost experimental implementation can be done with older TNLC technology. However, these devices, intended for display applications, exhibit rather limited optical phase modulation properties in comparison with modern LCOS devices, such as a very low range of phase modulation and a general coupled intensity modulation. However, we show that a precise characterization of their retardance parameters permits their operation in useful modulation configurations. As examples, we include one continuous phase-only configuration useful for reproducing the optimal triplicator phase grating, and a binary π-phase modulation. We include experiments with the realization of different phase diffraction gratings, and their combination with spiral phase patterns and lens functions to generate a variety of vortex beams.

  5. Crystal science fundamentals

    OpenAIRE

    Ramachandran, V.; Halfpenny, PJ; Roberts, KJ

    2017-01-01

    The fundamentals of crystal science notably crystallography, crystal chemistry, crystal defects, crystal morphology and the surface chemistry of crystals are introduced with particular emphasis on organic crystals.

  6. Quasi-periodic Fibonacci and periodic one-dimensional hypersonic phononic crystals of porous silicon: Experiment and simulation

    Energy Technology Data Exchange (ETDEWEB)

    Aliev, Gazi N., E-mail: g.aliev@bath.ac.uk; Goller, Bernhard [Department of Physics, University of Bath, Bath BA2 7AY (United Kingdom)

    2014-09-07

    A one-dimensional Fibonacci phononic crystal and a distributed Bragg reflector were constructed from porous silicon. The structures had the same number of layers and similar acoustic impedance mismatch, and were electrochemically etched in highly boron doped silicon wafers. The thickness of the individual layers in the stacks was approximately 2 μm. Both types of hypersonic band gap structure were studied by direct measurement of the transmittance of longitudinal acoustic waves in the 0.1–2.6 GHz range. Acoustic band gaps deeper than 50 dB were detected in both structures. The experimental results were compared with model calculations employing the transfer matrix method. The acoustic properties of periodic and quasi-periodic structures in which half-wave retarding bi-layers do not consist of two quarter-wave retarding layers are discussed. The strong correlation between width and depth of gaps in the transmission spectra is demonstrated. The dominant mechanisms of acoustic losses in porous multilayer structures are discussed. The elastic constants remain proportional over our range of porosity, and hence, the Grüneisen parameter is constant. This simplifies the expression for the porosity dependence of the Akhiezer damping.

  7. Effect of pest controlling neem and mata-raton leaf extracts on greenhouse gas emissions from urea-amended soil cultivated with beans: a greenhouse experiment.

    Science.gov (United States)

    Méndez-Bautista, Joaquín; Fernández-Luqueño, Fabián; López-Valdez, Fernando; Mendoza-Cristino, Reyna; Montes-Molina, Joaquín A; Gutierrez-Miceli, Federico A; Dendooven, L

    2010-10-01

    In a previous laboratory experiment, extracts of neem (Azadirachta indica A. Juss.) and Gliricidia sepium Jacquin, locally known as mata-raton, used to control pests on crops, inhibited emissions of CO(2) from a urea-amended soil, but not nitrification and N(2)O emissions. We investigated if these extracts when applied to beans (Phaseolus vulgaris L.) affected their development, soil characteristics and emissions of carbon dioxide (CO(2)) and nitrous oxide (N(2)O) in a greenhouse environment. Untreated beans and beans planted with lambda-cyhalothrin, a commercial insecticide, served as controls. After 117days, shoots of plants cultivated in soil amended with urea or treated with lambda-cyhalothrin, or extracts of neem or G. sepium were significantly higher than when cultivated in the unamended soil, while the roots were significantly longer when plants were amended with urea or treated with leaf extracts of neem or G. sepium than when treated with lambda-cyhalothrin. The number of pods, fresh and dry pod weight and seed yield was significantly higher when bean plants were treated with leaf extracts of neem or G. sepium treatments than when left untreated and unfertilized. The number of seeds was similar for the different treatments. The number of nodules was lower in plants fertilized with urea, treated with leaf extracts of neem or G. sepium, or with lambda-cyhalothrin compared to the unfertilized plants. The concentrations of NH(4)(+), NO(2)(-) and NO(3)(-) decreased significantly over time with the lowest concentrations generally found at harvest. Treatment had no significant effect on the concentrations of NH(4)(+) and NO(2)(-), but the concentration of NO(3)(-) was significantly lower in the unfertilized soil compared to the other treatments. It was found that applying extracts of neem or G. sepium leaves to beans favored their development when compared to untreated plants, but had no significant effect on nitrification in soil.

  8. Phyto-crystallization of silver and gold by Erigeron annuus (L. Pers flower extract and catalytic potential of synthesized and commercial nano silver immobilized on sodium alginate hydrogel

    Directory of Open Access Journals (Sweden)

    Palanivel Velmurugan

    2016-05-01

    Full Text Available A green, eco-friendly approach for the synthesis of silver and gold nanoparticles (AgNPs and AuNPs using Erigeron annuus (L. pers flower extract as both the reducing and capping agent is reported for the first time. Optimal nanoparticle production was achieved by adjusting various parameters including pH, extract concentration, metal ion concentration, and time. Initial verification of AgNP and AuNP production was done by visual observation and measuring surface plasmon spectra at 434 and 537 nm, respectively. The synthesized AgNPs and AuNPs were characterized by high resolution-transmission electron microscopy (HR-TEM, X-ray diffraction (XRD, energy dispersive spectrophotometry (EDS, Fourier transform infrared spectroscopy (FTIR and zeta potential. The catalytic potential of E. annuus flower extract, silver ions, synthesized AgNPs, commercial grade AgNPs, and a mixture of flower extract and AgNPs immobilized on sodium alginate hydrogel beads (Na/Al HB was analyzed. The ability of these immobilized materials to degrade methylene blue was investigated. Commercial grade AgNPs immobilized with Na/Al HB 1.5 g/20 mL were observed to have good catalytic activity followed by a mixture of synthesized AgNPs immobilized with Na/Al HB and E. annuus flower extract immobilized with Na/Al HB at 1.5 g/20 mL.

  9. The effect of O-methylated flavonoids and other co-metabolites on the crystallization and purification of artemisinin.

    Science.gov (United States)

    Suberu, John O; Yamin, Peyman; Leonhard, Kai; Song, Lijiang; Chemat, Smain; Sullivan, Neil; Barker, Guy; Lapkin, Alexei A

    2014-02-10

    Methoxylated flavonoids casticin, artemetin and retusin were identified as putative causative factors for low crystallization yields of artemisinin from extracts. Comparative profiling of biomass grown in different countries found elevated levels (∼60% higher) of artemetin in the East African biomass, which also demonstrates poor crystallization yields. The single compound and the combined doping experiments at 0, 25 and 50 μg mL⁻¹ doping levels showed that artemetin (50 μg mL⁻¹) caused a reduction in the amount of artemisinin crystallized by ca. 60%. A combination of the three flavonoids at 50 μg mL⁻¹ almost completely inhibited crystallization, reducing the yield by 98%. Treatment of extracts by adsorbents efficiently resolves the problem of low crystallization yield.

  10. [Melanin Synthesis was Affected by Extracts of 22 Kinds Chinese Herbs of Acid Taste: an Experi- mental Study].

    Science.gov (United States)

    Zhang, Li-ping; Liang, Juan; Chen, Bin; Wang, Ying-hao

    2015-05-01

    To confirm the inhibitory effect of Chinese herbs of acid taste on melanin synthesis. Active ingredients of 22 kinds Chinese herbs of acid tastes were extracted by alkali extraction and acid precipitation, alcohol extraction, and water extraction, respectively, which was then dispensed into 25.00, 12.50, and 6.25 g/L suspension. Their effects on activities of tyrosinase were detected using mushroom-tyrosinase-DOPA speed oxidation. Their inhibition rates on activities of tyrosinase were respectively compared with inhibition rates of 1.0, 0.5, and 0.1 mmol/L arbutin. The 22 kinds Chinese herbs of acid taste included Cornus Officinalis, Crataegus pinnatifida, dark plum fruit, Schisandra Chinensis, Chaenomeles sinensis Koehne, Reynoutria japonica Houtt, Achyranthes Bidentata, Sanguisorba officinalis L., Semen Ziziphi Spinosae, Herba Ecliptae, blueberry, immature bitter orange, submature bitter orange, Prunus mume Var, Hovenia acerba Lindl., Fructus Mori, Pomegranate Rind, white paeony root, Rosa laevigata Michx., Portulaca oleracea L, Terminalia chebula Retz, Rhus chinensis Mill. Their alkaline extractions showed inhibition to activities of tyrosinase to different degrees except Herba Ecliptae. Of them, the highest inhibition rate (88.49% ± 9.98%) was got by dark plum fruit at 25 g/L, while the lowest inhibition rate (11.22% ± 3.36%) was got by immature bitter orange at 6.25 g/L. Their alcohol extractions showed inhibition to activities of tyrosinase to different degrees except Herba Ecliptae. Of them, the highest inhibition rate (75.92% ± 5.57%) was got by Hovenia acerba Lindl. at 25 g/L, while the lowest inhibition rate (9.60% ± 1.15%) was got by submature bitter orange at 6.25 g/L. Their water extractions all had inhibition on activities of tyrosinase. Of them, the highest inhibition rate (54.23% ± 3.56%) was got by Fructus Mori at 25 g/L, while the lowest inhibition rate (10.25% ± 1.83%) was got by Semen Ziziphi Spinosae at 6.25 g/L. Compared with 1 mmol

  11. A study of RHIC crystal collimation

    CERN Document Server

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

    1998-01-01

    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 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 w...

  12. 正交实验法优化西瓜番茄红素的提取工艺%The Orthogonal Experiment Method Extracting Lycopene in Watermelon

    Institute of Scientific and Technical Information of China (English)

    刘义庆

    2014-01-01

    In this paper, lycopene was extracted from watermelon with the component solvent of ethyl acetate and acetone,the volume ratio was 7∶1. Effect of extraction time, extraction temperature, solid-liquid ratio, pH on extraction of watermelon lycopene were studied. The last orthogonal experiments showed the optimum conditions:solid-liquid ratio was 1∶4, the temperature was 45℃, the time was 50 min, pH=6.%采用了体积比为7∶1的乙酸乙酯-丙酮混合溶剂,提取新鲜西瓜中的番茄红素,考察了提取溶剂、提取时间、提取温度、料液比、pH等因索对提取液吸光度的影响,最后用正交试验确定了最佳工艺条件,分析结果表明:料液比为1∶4,温度为45℃,时间为50 min,pH=6时提取效果最好。

  13. Measurement of z-axis deviation angle of electro-optic crystal by conoscopic interference

    Science.gov (United States)

    Li, Dong; Liu, Yong; Liu, Xu; Jiang, Hongzhen; Zheng, Fanglan

    2016-09-01

    Properties of plasma electrode pockels cell is directly affected by the Z-axis deviation angle of the electro-optic crystal. Therefore, high precision measurement of the Z-axis deviation angle is indispensable. By using conoscopic interference technique, a measurement system for Z-axis deviation angle of electro-optic crystal is introduced. The principle of conoscopic interference method is described in detail, and a series of techniques are implied in this measurement system to improve the accuracy. High-precision positioning method of the crystal based on Michelson interference is proposed to determine the normal consistency of crystal, which can ensure the high positioning repeatability of crystal in the measurement process. The positioning comparison experiment of the crystal shows that the standard deviation of our method is less than 1pixel, which is much better than the traditional method (nearly 4pixels). Moreover, melatope extraction algorithm of optical axis based on image matching technique is proposed to ensure the melatope can be extracted in high precision. Calibration method of the normal of transmission surface of crystal is also proposed. The experiment results show that the PV and rms of Z-axis deviation angle is less than 0.05mrad and 0.02mrad, respectively. The repeatability accuracy is less than 0.01mrad.

  14. A crystal barrel

    CERN Multimedia

    2007-01-01

    The production of crystals for the barrel of the CMS electromagnetic calorimeter has been completed. This is an important milestone for the experiment, which received the last of its 62,960 crystals on 9 March. The members of the team responsible for the crystal acceptance testing at CERN display the last crystal for the CMS electromagnetic calorimeter barrel. From left to right: Igor Tarasov, Etiennette Auffray and Hervé Cornet.One of the six machines specially developed to measure 67 different parameters on each crystal. Igor Tarasov is seen inserting the last batch of crystals into the machine. The last of the 62,960 CMS barrel crystals arrived at CERN on 9 March. Once removed from its polystyrene protection, this delicate crystal, like thousands of its predecessors, will be inserted into the last of the 36 supermodules of the barrel electromagnetic calorimeter in a few days' time. This marks the end of an important chapter in an almost 15-year-long journey by the CMS crystals team, some of whose member...

  15. IonLab. A remote-controlled experiment for academic and vocational education and training on extraction chromatography and ion exchange

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, Wolfgang; Fournier, Claudia; Vahlbruch, Jan-Willem; Walther, Clemens [Leibniz Univ., Hannover (Germany). Inst. for Radioecology and Radiation Protection (IRS)

    2016-07-01

    As a major contribution to modern web-based education and training in nuclear chemistry we have built and operated a remote-controlled experiment - IonLab - as part of the integrated EUFP7 project CINCHII. The setup is suitable for teaching basics on extraction chromatography and ion exchange using radionuclides. We describe separation of the beta emitting nuclides Sr-90 and Y-90 followed by radiometric detection, but the experiment is easily adapted to other separation schemes. This approach is aimed at institutions in academic or vocational education who need to convey the skills of handling radioactive (or otherwise dangerous, e.g. biotoxic) substances without appropriately licensed laboratory space for teaching. This camera-monitored remote controlled lab experiment has proved to be much closer to a real hands-on training and superior to a mere computer simulation.

  16. Method of bioindication for evaluation of the effects of plant extracts on cell monolayer in acute and chronic experiments.

    Science.gov (United States)

    Seregina, M V; Mikhailova, L P

    2002-04-01

    Acute and chronic toxicities of plant extracts for external use were studied on a model of cell monolayer. This method detects the toxic dose of the agent during the first stage of the study; the activity of this dose and severity of damaging effect can be further studied on experimental animals. An advantage of the method is high informative value of preliminary investigation in the development of new low-toxic agents.

  17. Effects of Various Dental Materials on Alkaline Phosphatase Extracted from Pulp: An Experiment for the Biochemistry Laboratory.

    Science.gov (United States)

    Thompson, Lorin R.

    1980-01-01

    A laboratory experiment that demonstrates the effects of various dental materials on a representative enzyme from the pulp is outlined. The experiment encourages students to consider the effects that various restorative materials and techniques might have on enzymes in the living pulp. (Author/MLW)

  18. Nanoindentation Induced Deformation and Pop-in Events in a Silicon Crystal: Molecular Dynamics Simulation and Experiment.

    Science.gov (United States)

    Jiapeng, Sun; Cheng, Li; Han, Jing; Ma, Aibin; Fang, Liang

    2017-08-31

    Silicon has such versatile characteristics that the mechanical behavior and deformation mechanism under contact load are still unclear and hence are interesting and challenging issues. Based on combined study using molecular dynamics simulations and experiments of nanoindentation on Si(100), the versatile deformation modes, including high pressure phase transformation (HPPT), dislocation, median crack and surface crack, were found, and occurrence of multiple pop-in events in the load-indentation strain curves was reported. HPPTs are regard as the dominant deformation mode and even becomes the single deformation mode at a small indentation strain (0.107 in simulations), suggesting the presence of a defect-free region. Moreover, the one-to-one relationship between the pop-in events and the deformation modes is established. Three distinct mechanisms are identified to be responsible for the occurrence of multiple pop-in events in sequence. In the first mechanism, HPPTs from Si-I to Si-II and Si-I to bct5 induce the first pop-in event. The formation and extrusion of α-Si outside the indentation cavity are responsible for the subsequent pop-in event. And the major cracks on the surface induces the pop-in event at extreme high load. The observed dislocation burst and median crack beneath the transformation region produce no detectable pop-in events.

  19. Low temperature EPR investigation of Co2+ ion doped into rutile TiO2 single crystal: Experiments and simulations

    Science.gov (United States)

    Zerentürk, A.; Açıkgöz, M.; Kazan, S.; Yıldız, F.; Aktaş, B.

    2017-02-01

    In this paper, we present the results of X-band EPR spectra of Co2+ ion doped rutile (TiO2) which is one of the most promising memristor material. We obtained the angular variation of spectra in three mutually perpendicular planes at liquid helium (7-13 K) temperatures. Since the impurity ions have ½ effective spin and 7/2 nuclear spin, a relatively simple spin Hamiltonian containing only electronic Zeeman and hyperfine terms was utilized. Two different methods were used in theoretical analysis. Firstly, a linear regression analysis of spectra based on perturbation theory was studied. However, this approach is not sufficient for analyzing Co+2 spectra and leads to complex eigenvectors for G and A tensors due to large anisotropy of eigenvalues. Therefore, all spectra were analyzed again with exact diagonalization of spin Hamiltonian and the high accuracy eigenvalues and eigenvectors of G and A tensors were obtained by taking into account the effect of small sample misalignment from the exact crystallographic planes due to experimental conditions. Our results show that eigen-axes of g and A tensors are parallel to crystallographic directions. Hence, our EPR experiments proves that Co2+ ions substitute for Ti4+ ions in lattice. The obtained principal values of g tensor are gx=2.110(6), gy=5.890(2), gz=3.725(7) and principal values of hyperfine tensor are Ax=42.4, Ay=152.7, Az=26 (in 10-4/cm).

  20. In Situ Observation of NaCI Crystal Growth by the Vapor Diffusion Method with a Mach-Zehnder Interferometer

    Institute of Scientific and Technical Information of China (English)

    ZHAO Jing; MIAO Hong; DUAN Li; KANG Qi; HE Ling-Hui

    2011-01-01

    Vapor diffusion experiments with different thicknesses of oil barriers are observed by a real-time optical diagnostic system consisting of a Mach Zehnder interferometer, a microscope and an image processor. Spatiotemporal analysis is first employed to extract the absolute concentration evolution and supersaturation during the entire crystallization process. The nucleation and crystal growth processes are then analyzed. It is found that the crystallization process can be easily classified into four stages in our experiments, according to the analysis of interferograms and the absolute concentration curve. This can help us understand the details of crystal growth. The rule of quality change of crystals with increasing thickness of oil barriers is also analyzed, and could be interpreted by the absolute concentration variation and crystallization phase diagram.%Vapor diffusion experiments with different thicknesses of oil barriers are observed by a real-time optical diagnostic system consisting of a Mach Zehnder interferometer,a microscope and an image processor.Spatiotemporal analysis is first employed to extract the absolute concentration evolution and supersaturation during the entire crystallization process.The nucleation and crystal growth processes are then analyzed.It is found that the crystallization process can be easily classified into four stages in our experiments,according to the analysis of interferograms and the absolute concentration curve.This can help us understand the details of crystal growth.The rule of quality change of crystals with increasing thickness of oil barriers is also analyzed,and could be interpreted by the absolute concentration variation and crystallization phase diagram.The growth of large crystals with a high degree of perfection is essential in the chemical industry and the protein field.Vapor diffusion[1] is the most widely used technique in protein crystallization,the principle of which is that the solution gradually reaches

  1. An insight into crystal, electronic, and local structures of lithium iron silicate (Li{sub 2}FeSiO{sub 4}) materials upon lithium extraction

    Energy Technology Data Exchange (ETDEWEB)

    Kamon-in, O. [School of Ceramic Engineering, Suranaree University of Technology, Nakhonratchasima 30000 (Thailand); Klysubun, W. [Synchrotron Light Research Institute, Nakhonratchasima 30000 (Thailand); Thailand Center of Excellence in Physics, Commission of Higher Education, Bangkok 10400 (Thailand); Limphirat, W. [Synchrotron Light Research Institute, Nakhonratchasima 30000 (Thailand); Srilomsak, S. [School of Ceramic Engineering, Suranaree University of Technology, Nakhonratchasima 30000 (Thailand); Meethong, N., E-mail: nonmee@kku.ac.th [Department of Physics, Faculty of Science, Khon Kaen University, Khon Kaen 40002 (Thailand)

    2013-05-01

    Recently, orthosilicate, Li{sub 2}MSiO{sub 4} (where M=transition metal) materials have been attracting considerable attention for potential use as a new generation cathode for Li-ion batteries due to their safety, low toxicity, and low cost characteristics. In addition, the presence of two Li{sup +} ions in the molecule offers a multiple electron-charge transfer (M{sup 2+}/M{sup 3+} and M{sup 3+}/M{sup 4+} redox couples), thus allowing a high achievable capacity of more than 320 mA h/g per M unit. Good electrochemical properties of Li{sub 2}FeSiO{sub 4} have been reported through several approaches such as downsizing of the particles, carbon-coating, etc. However, in addition to electrochemical performance, fundamental understanding regarding crystal, electronic and local structure changes during charge/discharge processes is also important and needs more rigorous investigation. In this work, lithium iron silicates (Li{sub 2}FeSiO{sub 4}/C) in space group of Pnma: a=10.6671(3) Å, b=6.2689(2) Å, and c=5.0042(2) Å have been prepared by solid-state reaction. The synthesized as well as chemical delithiated samples have been characterized by XRD, HRTEM, AAS and XAS techniques. We will show the results focusing on Fe K-edge XANES, EXAFS, HRTEM and XRD of the Li{sub 2−x}FeSiO{sub 4} samples and discuss how the crystal, electronic, and local structure changes upon Li{sup +} de-intercalation.

  2. Large-scale single-crystal growth of (CH3)2NH2CuCl3 for neutron scattering experiments

    Science.gov (United States)

    Park, Garam; Oh, In-Hwan; Park, J. M. Sungil; Park, Seong-Hun; Hong, Chang Seop; Lee, Kwang-Sei

    2016-05-01

    Neutron scattering studies on low-dimensional quantum spin systems require large-size single-crystals. Single-crystals of (CH3)2NH2CuCl3 showing low-dimensional magnetic behaviors were grown by a slow solvent evaporation method in a two-solvent system at different temperature settings. The best results were obtained for the bilayer solution of methanol and isopropanol with a molar ratio of 2:1 at 35 °C. The quality of the obtained single-crystals was tested by powder and single-crystal X-ray diffraction and single-crystal neutron diffraction. In addition, to confirm structural phase transitions (SPTs), thermal analysis and single-crystal X-ray diffraction at 300 K and 175 K, respectively, were conducted, confirming the presence of a SPT at Tup=288 K on heating and Tdown=285 K on cooling.

  3. Effect of pest controlling neem and mata-raton leaf extracts on greenhouse gas emissions from urea-amended soil cultivated with beans: A greenhouse experiment

    Energy Technology Data Exchange (ETDEWEB)

    Mendez-Bautista, Joaquin [Laboratory of Soil Ecology, Cinvestav, Mexico D.F. (Mexico); Fernandez-Luqueno, Fabian [Laboratory of Soil Ecology, Cinvestav, Mexico D.F. (Mexico); Department of Electromechanics, Renewable Energy Engineering, UTTulancingo, Hidalgo (Mexico); Lopez-Valdez, Fernando [Laboratory of Soil Ecology, Cinvestav, Mexico D.F. (Mexico); C.I.B.A.-I.P.N., Tepetitla de Lardizabal, Tlaxcala (Mexico); Mendoza-Cristino, Reyna [Laboratory of Soil Ecology, Cinvestav, Mexico D.F. (Mexico); Montes-Molina, Joaquin A.; Gutierrez-Miceli, Federico A. [Laboratorio de Biotecnologia Vegetal, Instituto Tecnologico de Tuxtla-Gutierrez, Tuxtla-Gutierrez (Mexico); Dendooven, L., E-mail: dendoove@cinvestav.mx [Laboratory of Soil Ecology, Cinvestav, Mexico D.F. (Mexico)

    2010-10-01

    In a previous laboratory experiment, extracts of neem (Azadirachta indica A. Juss.) and Gliricidia sepium Jacquin, locally known as mata-raton, used to control pests on crops, inhibited emissions of CO{sub 2} from a urea-amended soil, but not nitrification and N{sub 2}O emissions. We investigated if these extracts when applied to beans (Phaseolus vulgaris L.) affected their development, soil characteristics and emissions of carbon dioxide (CO{sub 2}) and nitrous oxide (N{sub 2}O) in a greenhouse environment. Untreated beans and beans planted with lambda-cyhalothrin, a commercial insecticide, served as controls. After 117 days, shoots of plants cultivated in soil amended with urea or treated with lambda-cyhalothrin, or extracts of neem or G. sepium were significantly higher than when cultivated in the unamended soil, while the roots were significantly longer when plants were amended with urea or treated with leaf extracts of neem or G. sepium than when treated with lambda-cyhalothrin. The number of pods, fresh and dry pod weight and seed yield was significantly higher when bean plants were treated with leaf extracts of neem or G. sepium treatments than when left untreated and unfertilized. The number of seeds was similar for the different treatments. The number of nodules was lower in plants fertilized with urea, treated with leaf extracts of neem or G. sepium, or with lambda-cyhalothrin compared to the unfertilized plants. The concentrations of NH{sub 4}{sup +}, NO{sub 2}{sup -} and NO{sub 3}{sup -} decreased significantly over time with the lowest concentrations generally found at harvest. Treatment had no significant effect on the concentrations of NH{sub 4}{sup +} and NO{sub 2}{sup -}, but the concentration of NO{sub 3}{sup -} was significantly lower in the unfertilized soil compared to the other treatments. It was found that applying extracts of neem or G. sepium leaves to beans favored their development when compared to untreated plants, but had no significant

  4. Studying the high x frontier with A Fixed-Target ExpeRiment at the LHC

    CERN Document Server

    Rakotozafindrabe, A; Arnaldi, R; Brodsky, S J; Chambert, V; Didelez, J P; Ferreiro, E G; Fleuret, F; Genolini, B; Hadjidakis, C; Lansberg, J P; Lorce, C; Rosier, P; Schienbein, I; Scomparin, E; Uggerhoj, U I

    2013-01-01

    The opportunities which are offered by a next generation and multi-purpose fixed-target experiment exploiting the proton and lead LHC beams extracted by a bent crystal are outlined. In particular, such an experiment can greatly complement facilities with lepton beams by unraveling the partonic structure of polarised and unpolarised nucleons and of nuclei, especially at large momentum fractions.

  5. Optimal recovery of high-purity rutin crystals from the whole plant of Fagopyrum esculentum Moench (buckwheat) by extraction, fractionation, and recrystallization.

    Science.gov (United States)

    Kim, Kyoung Heon; Lee, Ki Won; Kim, Dong Young; Park, Hyung Hwan; Kwon, Ik Boo; Lee, Hyong Joo

    2005-10-01

    Rutin, one of the flavonoids derived from plants, is increasingly in demand in the food, pharmaceutical, and cosmetic industries due to its various biological and physiological activities including antioxidation, anti-inflammation, and anti-hypertension. The whole plant of buckwheat (Fagopyrum esculentum Moench) is a major source of natural rutin. This study developed a low-cost process encompassing the efficient extraction, fractionation, and recrystallization to obtain high-purity rutin from buckwheat, and it could improve the economic utilization of this abundant low-value agricultural product. The sequential separation and purification procedures established in this study involved extraction with 50% (v/v) aqueous ethanol at 80 degrees C for 1 h followed by elution with water and aqueous ethanols at 20% and 30% (v/v) on a styrene-based resin column, and recrystallization at 4 degrees C for 12 h. These conditions resulted in the recovery of 92% of total rutin with over 95% purity. In the present study, high-purity rutin was obtained from whole buckwheat through low-cost processes, the separation and purification strategy established in this study could provide valuable information to the relevant industries.

  6. A tool to evaluate correspondence between extraction ion chromatographic peaks and peptide-spectrum matches in shotgun proteomics experiments.

    Science.gov (United States)

    Ruse, Cristian I; Peacock, Samantha; Ghiban, Cornel; Rivera, Keith; Pappin, Darryl J; Leopold, Peter

    2013-08-01

    Chromatographed peptide signals form the basis of further data processing that eventually results in functional information derived from data-dependent bottom-up proteomics assays. We seek to rank LC/MS parent ions by the quality of their extracted ion chromatograms. Ranked extracted ion chromatograms act as an intuitive physical/chemical preselection filter to improve the quality of MS/MS fragment scans submitted for database search. We identify more than 4900 proteins when considering detector shifts of less than 7 ppm. High quality parent ions for which the database search yields no hits become candidates for subsequent unrestricted analysis for PTMs. Following this rational approach, we prioritize identification of more than 5000 spectrum matches from modified peptides and confirmed the presence of acetylaldehyde-modified His/Lys. We present a logical workflow that scores data-dependent selected ion chromatograms and leverage information about semianalytical LC/LC dimension prior to MS. Our method can be successfully used to identify unexpected modifications in peptides with excellent chromatography characteristics, independent of fragmentation pattern and activation methods. We illustrate analysis of ion chromatograms detected in two different modes by RF linear ion trap and electrostatic field orbitrap.

  7. Correction of the equilibrium temperature caused by slight evaporation of water in protein crystal growth cells during long-term space experiments at International Space Station.

    Science.gov (United States)

    Fujiwara, Takahisa; Suzuki, Yoshihisa; Yoshizaki, Izumi; Tsukamoto, Katsuo; Murayama, Kenta; Fukuyama, Seijiro; Hosokawa, Kouhei; Oshi, Kentaro; Ito, Daisuke; Yamazaki, Tomoya; Tachibana, Masaru; Miura, Hitoshi

    2015-08-01

    The normal growth rates of the {110} faces of tetragonal hen egg-white lysozyme crystals, R, were measured as a function of the supersaturation σ parameter using a reflection type interferometer under μG at the International Space Station (NanoStep Project). Since water slightly evaporated from in situ observation cells during a long-term space station experiment for several months, equilibrium temperature T(e) changed, and the actual σ, however, significantly increased mainly due to the increase in salt concentration C(s). To correct σ, the actual C(s) and protein concentration C(p), which correctly represent the measured T(e) value in space, were first calculated. Second, a new solubility curve with the corrected C(s) was plotted. Finally, the revised σ was obtained from the new solubility curve. This correction method successfully revealed that the 2.8% water was evaporated from the solution, leading to 2.8% increase in the C(s) and C(p) of the solution.

  8. Comparison between experiment and theory in the temperature variation of film tension above the bulk isotropic transition in free-standing liquid-crystal films.

    Science.gov (United States)

    Veum, M; Duelge, L; Droske, J; Nguyen, H T; Huang, C C; Mirantsev, L V

    2009-09-01

    Using differential scanning calorimetry, the transition enthalpies and temperatures for the bulk smectic-isotropic phase transition have been measured for a series of liquid-crystal compounds. For five compounds, those values were used as parameters in a microscopic mean-field model to predict the temperature dependence of the difference in free-energy density between a sample of material in a free-standing smectic film and that in the bulk. The model predicts a weak temperature dependence below the bulk clearing point and a pronounced monotonic increase with temperature above the transition temperature. The compounds used in this study were chosen specifically because they were also the subject of a previous independent experimental study [M. Veum, Phys. Rev. E 74, 011703 (2006)] that demonstrated a sudden monotonic increase in the free-standing film tension with temperature, which is qualitatively consistent with the predictions of the above-mentioned mean-field model. This study presents a direct and quantitative comparison between the predictions of the mean-field model and the results from previous tension experiments.

  9. Quantitative studies and taste reconstitution experiments of the sour and lingering mouthful orosensation in a debittered extract of traditional Japanese dried and fermented skipjack tuna (hongarebushi).

    Science.gov (United States)

    Haseleu, Gesa; Lubian, Elisabetta; Mueller, Stefan; Shi, Feng; Koenig, Thorsten

    2013-04-03

    Hongarebushi, Japanese dried skipjack tuna and a high quality ingredient of Japanese dashi, was investigated for its taste active composition. The recent investigation focused on a debittered fish fraction, which revealed a strong umami and salt impact accompanied with a pleasant and pronounced sourness. Whereas the umami and salt tastes could be correlated to monosodium glutamate (MSG), ribonucleotides, and mineral salts, the pleasant sourness was not exclusively induced by organic acids. The essential compound imparting the sour orosensation, persistence, and mouthfulness of the debittered skipjack tuna extract was investigated, and omission experiments emphasized the impact of N-acetylglutamic acid (NAG) on the overall taste sensation of the debittered fish extract. This metabolite, which is known to be present as a minor constituent in animal- and plant-derived foods, was quantified in this study for the first time in seafood, soybean products, dried shiitake mushrooms, and dried fish in notable amounts. Furthermore, it was described for the first time as an essential taste contributor to the nonvolatile profile of a foodstuff, in this case of a debittered extract of hongarebushi.

  10. 酮麝香-二甲苯麝香双液相萃取结晶%TWO LIQUID PHASE EXTRACTIVE CRYSTALLIZATION OF MUSK KETONE AND MUSK XYLENE

    Institute of Scientific and Technical Information of China (English)

    曲红梅; 白鹏; 周立山; 杨志才

    2004-01-01

    To evaluate the effect of two liquid phase on the separation of musks mixture, the phase equilibria of musk ketone+musk xylene + dimethyl sulfoxide + heptane system were studied for the first time. The whole and every part of the phase equilibrium for the quaternary system were shown by three-dimensional phase diagrams, the liquid-liquid equilibria, solid-liquid equilibria and solid-liquid-liquid equilibria of the quaternary system were also shown. As a result, the compositions of musks in the equilibrium liquid phases were different from those in the feed, that is, musk ketone was enriched in dimethyl sulfoxide phase while musk xylene was enriched in heptane phase. So these equilibrium liquid phases were useful in separating musk ketone and musk xylene. On the basis of these results, a new process “two liquid phase extractive crystallization” was proposed to separate the eutectics of musk ketone and musk xylene.

  11. Optimization of Lead and Silver Extraction from Zinc Plant Residues in the Presence of Calcium Hypochlorite Using Statistical Design of Experiments

    Science.gov (United States)

    Behnajady, Bahram; Moghaddam, Javad

    2014-12-01

    In this work, a chloride/hypochlorite leaching process was performed for zinc plant residues. Sodium chloride and calcium hypochlorite were used as leaching and oxidizing agents, respectively. Fractional factorial method has been used to test main effects, and interactions among factors were investigated. The statistical software named Design-Expert 7 has been utilized to design experiments and subsequent analysis. Parameters and their levels were reaction time ( t = 16 and 120 minutes), reaction temperature [ T = 303 K and 343 K (30 °C and 70 °C)], solid-to-liquid ratio ( S/ L = 1/6 and 1/38), pH (pH = 0.5 and 2), and Ca(OCl)2 concentration ( C = 0.6 and 3 g/L). Analysis of variance was also employed to determine the relationship between experimental conditions and yield levels. Results showed that reaction temperature and pH were significant parameters for both lead and silver extractions but solid-to-liquid ratio had significant effect only on lead extraction. Increasing pH reduced leaching efficiency of lead and silver. However, increasing reaction temperature promoted the extraction of lead and silver. Ultimate optimum conditions from this study were t 1: 16 min, T 2: 343 K (70 °C), ( S/ L)2: 1/38, pH1: 0.5, and C 1: 0.6 g/L. Under these conditions, extractions of lead and silver were 93.60 and 49.21 pct, respectively.

  12. Experience in Treatment of Elderly Patients with Tooth Extraction%老年拔牙患者的治疗体会

    Institute of Scientific and Technical Information of China (English)

    熊书函; 刘道华; 赖璟研

    2014-01-01

    Objective To investigate the clinical experience in treatment of elderly patients with tooth extraction. Methods A retrospective analysis of our hospital since 2010 January to 2014 June, there were 5182 cases of outpatients and inpatients in elderly patients with extraction. Results In this group, 5182 cases in 3 cases of bleeding after tooth extraction more, after thoroughly cleaning alveolar fossa, suture wound edge after cure. 121 cases of postoperative pain symptoms are obvious, the anti-inflammatory and symptomatic treatment to cure. The remaining patients with tooth extraction wound healed, no infection and other serious complications. Conclusion Ful understanding of senile systemic disease, doctors have the ability of emergency treatment, the hospital emergency treatment facilities, improve the quality of life of the elderly.%目的探讨老年拔牙患者的临床治疗体会。方法回顾性分析选择我院自2010年1月~2014年6月,共收治门诊和住院5182例老年拔牙患者。结果本组5182例中有3例拔牙术后出血较多,经再次彻底清理牙槽窝,缝合创缘后治愈。术后疼痛症状明显者121例,经抗炎对症处理后治愈。其余患者拔牙创面一期愈合,均未发生感染和其他严重并发症。结论充分了解老年全身性疾病,医生具备应急处理的能力,院方应急处理设备齐全,提高老年人的生活质量。

  13. Axion Crystals

    CERN Document Server

    Ozaki, Sho

    2016-01-01

    The low-energy effective theories for gapped insulators are classified by three parameters: permittivity $\\epsilon$, permeability $\\mu$, and theta angle $\\theta$. Crystals with periodic $\\epsilon$ are known as photonic crystals. We here study the band structure of photons in a new type of crystals with periodic $\\theta$ (modulo $2\\pi$) in space, which we call the axion crystals. We find that the axion crystals have a number of new properties that the usual photonic crystals do not possess, such as the helicity-dependent photonic band gaps and the nonrelativistic gapless dispersion relation at small momentum. We briefly discuss possible realizations of axion crystals in condensed matter systems as well as high-energy physics.

  14. Enhanced sandwich immunoassay using antibody-functionalized magnetic iron-oxide nanoparticles for extraction and detection of soluble transferrin receptor on a photonic crystal biosensor.

    Science.gov (United States)

    Peterson, Ross D; Chen, Weili; Cunningham, Brian T; Andrade, Juan E

    2015-12-15

    Iron deficiency anemia (IDA) has detrimental effects on individuals and societies worldwide. A standard sandwich assay (SA) for the detection of soluble transferrin receptor (sTfR), a biomarker of IDA, on a photonic crystal (PC) biosensor was established, but it was susceptible to non-specific signals from complex matrixes. In this study, iron-oxide nanoparticles (fAb-IONs) were used as magnetic immuno-probes to bind sTfR and minimize non-specific signals, while enhancing detection on the PC biosensor. This inverse sandwich assay (IA) method completely bound sTfR with low variability (detection in sera (Liquichek™ control sera) on the PC biosensor using two certified ELISAs as reference methods. A linear dose-response curve was elicited at the fAb-IONs concentration in which the theoretical binding ratio (sTfR:fAb-IONs) was calculated to be 0.05) at 14 and 21 μg/mL, respectively. The inherent imprecision of the IA and reference ELISAs was σ(δ)=0.45 µg/mL and the mean biases for Liquichek™ 1, 2 and 3 were 0.18, 0.19 and -0.04 µg/mL, respectively. Whereas the inherent imprecision of the SA and reference ELISAs was σ(δ)=0.52 µg/mL and the biases for Liquichek™ 1, 2 and 3 were 0.66, 0.14 and -0.67 µg/mL, respectively. Thus, unlike the SA, the IA method measures sTfR with the same bias as the reference ELISAs. Combined magnetic separation and detection of nutrition biomarkers on PC biosensors represents a facile method for their accurate and reliable quantification in complex matrixes.

  15. Quantifying melting and mobilistaion of interstitial melts in crystal mushes

    Science.gov (United States)

    Veksler, Ilya; Dobson, Katherine; Hess, Kai-Uwe; Ertel-Ingrisch, Werner; Humphreys, Madeleine

    2015-04-01

    The deformation of crystals mushes and separation of melts and crystals in is critical to understanding the development of physical and chemical heterogeneity in magma chambers and has been invoked as an eruption trigger mechanism. Here we investigate the behaviour of the melt in the well characterised, classic crystal mush system of the Skaergaard intrusion by combining experimental petrology and the non-destructive 3D imaging methods. Starting materials for partial melting experiments were four samples from the upper Middle Zone of the Layered Series. Cylinders, 15 mm in diameter and 20 mm in length, were drilled out of the rock samples, placed in alumina crucibles and held for 5 days in electric furnaces at atmospheric pressure and 1050-1100 °C. Redox conditions set by the CO-CO2 gas mixture were kept close to those of the FMQ buffer. We then use spatially registered 3D x-ray computed tomography images, collected before and after the experiment, to determine the volume and distribution of the crystal framework and interstitial phases, and the volume, distribution and connectivity the interstitial phases that undergo melting and extraction while at elevated temperature. Image analysis has allowed us to quantify these physical changes with high spatial resolution. Our work is a first step towards quantitative understanding of the melt mobilisation and migration processes operating in notionally locked crystal rich magmatic systems.

  16. A Few Good Crystals Please

    Science.gov (United States)

    Judge, Russell A.; Snell, Edward H.

    1999-01-01

    Part of the challenge of macromolecular crystal growth for structure determination is obtaining an appropriate number of crystals with a crystal volume suitable for X-ray analysis. In this respect an understanding of the effect of solution conditions on macromolecule nucleation rates is advantageous. This study investigated the effects of solution conditions on the nucleation rate and final crystal size of two crystal systems; tetragonal lysozyme and glucose isomerase. Batch crystallization plates were prepared at given solution concentration and incubated at set temperatures over one week. The number of crystals per well with their size and axial ratios were recorded and correlated with solution conditions. Duplicate experiments indicate the reproducibility of the technique. Results for each system showing the effect of supersaturation, incubation temperature and solution pH on nucleation rates will be presented and discussed. In the case of lysozyme, having optimized solution conditions to produce an appropriate number of crystals of a suitable size, a batch of crystals were prepared under exactly the same conditions. Fifty of these crystals were analyzed by x-ray techniques. The results indicate that even under the same crystallization conditions, a marked variation in crystal properties exists.

  17. The rheology of crystal-rich magmas (Kuno Award Lecture)

    Science.gov (United States)

    Huber, Christian; Aldin Faroughi, Salah; Degruyter, Wim

    2016-04-01

    The rheology of magmas controls not only eruption dynamics but also the rate of transport of magmas through the crust and to a large extent the rate of magma differentiation and degassing. Magma bodies stalled in the upper crust are known to spend most of their lifespan above the solidus at a high crystal content (Cooper and Kent, 2014; Huber et al., 2009), where the probability of melt extraction (crystal fractionation) is the greatest (Dufek and Bachmann, 2010). In this study, we explore a new theoretical framework to study the viscosity of crystal bearing magmas. Since the seminal work of A. Einstein and W. Sutherland in the early 20th century, it has been shown theoretically and tested experimentally that a simple self-similar behavior exist between the relative viscosity of dilute (low crystal content) suspensions and the particle volume fraction. The self-similar nature of that relationship is quickly lost as we consider crystal fractions beyond a few volume percent. We propose that the relative viscosity of crystal-bearing magmas can be fully described by two state variables, the intrinsic viscosity and the crowding factor (a measure of the packing threshold in the suspension). These two state variables can be measured experimentally under different conditions, which allows us to develop closure relationships in terms of the applied shear stress and the crystal shape and size distributions. We build these closure equations from the extensive literature on the rheology of synthetic suspensions, where the nature of the particle shape and size distributions is better constrained and apply the newly developed model to published experiments on crystal-bearing magmas. We find that we recover a self-similar behavior (unique rheology curve) up to the packing threshold and show that the commonly reported break in slope between the relative viscosity and crystal volume fraction around the expected packing threshold is most likely caused by a sudden change in the state

  18. A drunken search in crystallization space.

    Science.gov (United States)

    Fazio, Vincent J; Peat, Thomas S; Newman, Janet

    2014-10-01

    The REMARK280 field of the Protein Data Bank is the richest open source of successful crystallization information. The REMARK280 field is optional and currently uncurated, so significant effort needs to be applied to extract reliable data. There are well over 15 000 crystallization conditions available commercially from 12 different vendors. After putting the PDB crystallization information and the commercial cocktail data into a consistent format, these data are used to extract information about the overlap between the two sets of crystallization conditions. An estimation is made as to which commercially available conditions are most appropriate for producing well diffracting crystals by looking at which commercial conditions are found unchanged (or almost unchanged) in the PDB. Further analyses include which commercial kits are the most appropriate for shotgun or more traditional approaches to crystallization screening. This analysis suggests that almost 40% of the crystallization conditions found currently in the PDB are identical or very similar to a commercial condition.

  19. The fluid phenomena in the crystallization of the protein crystal

    Institute of Scientific and Technical Information of China (English)

    Duan Li; Kang Qi

    2008-01-01

    This paper reports that an optical diagnostic system consisting of Maeh-Zehnder interferometer with a phase shift device and image processor has been used for study of the kinetics of protein crystal growing process. The crystallization process of protein crystal by vapour diffusion is investigated. The interference fringes are observed in real time. The present experiment demonstrates that the diffusion and the sedimentation influence the crystallization of protein crystal which grows in solution, and the concentration capillary convection associated with surface tension occurs at the vicinity of free surface of the protein mother liquor, and directly affects on the outcome of protein crystallization. So far the detailed analysis and the important role of the fluid phenomena in protein crystallization have been discussed a little in both space- and ground-based crystal growth experiments. It is also found that these fluid phenomena affect theoutcome of protein crystallization, regular growth, and crystal quality. This may explain the fact that many results of space-based investigation do not show overall improvement.

  20. Mixtures of Uncaria and Tabebuia extracts are potentially chemopreventive in CBA/Ca mice: a long-term experiment.

    Science.gov (United States)

    Budán, Ferenc; Szabó, István; Varjas, Tímea; Nowrasteh, Ghodratollah; Dávid, Tamás; Gergely, Péter; Varga, Zsuzsa; Molnár, Kornélia; Kádár, Balázs; Orsós, Zsuzsa; Kiss, István; Ember, István

    2011-04-01

    A long-term experimental animal model was developed by our research group for the evaluation of potential chemopreventive effects. The inhibitory effects of agents on carcinogen (7,12-dimethylbenz[a]anthracene (DMBA) induced molecular epidemiological biomarkers, in this case the expression of key onco/suppressor genes were investigated. The expression pattern of c-myc, Ha-ras, Bcl-2, K-ras protooncogene and p53 tumour suppressor gene were studied to elucidate early carcinogenic and potential chemopreventive effects. The consumption of so-called Claw of Dragon tea (CoD™ tea) containing the bark of Uncaria guianensis, Cat's Claw (Uncaria sp. U. tomentosa) and Palmer trumpet-tree (Tabebuia sp. T. avellanedae) was able to decrease the DMBA-induced onco/suppressor gene overexpression in a short-term animal experiment. In a following study CBA/Ca mice were treated with 20 mg/kg bw DMBA intraperitoneally (i.p.) and the expression patterns of onco/suppressor genes were examined at several time intervals. According to the examined gene expression patterns in this long-term experiment the chemopreventive effect of CoD™ tea consumption could be confirmed.

  1. RNA Crystallization

    Science.gov (United States)

    Golden, Barbara L.; Kundrot, Craig E.

    2003-01-01

    RNA molecules may be crystallized using variations of the methods developed for protein crystallography. As the technology has become available to syntheisize and purify RNA molecules in the quantities and with the quality that is required for crystallography, the field of RNA structure has exploded. The first consideration when crystallizing an RNA is the sequence, which may be varied in a rational way to enhance crystallizability or prevent formation of alternate structures. Once a sequence has been designed, the RNA may be synthesized chemically by solid-state synthesis, or it may be produced enzymatically using RNA polymerase and an appropriate DNA template. Purification of milligram quantities of RNA can be accomplished by HPLC or gel electrophoresis. As with proteins, crystallization of RNA is usually accomplished by vapor diffusion techniques. There are several considerations that are either unique to RNA crystallization or more important for RNA crystallization. Techniques for design, synthesis, purification, and crystallization of RNAs will be reviewed here.

  2. Crystal Electrostatic Energy

    CERN Document Server

    Ivanchin, Alexander

    2010-01-01

    It has been shown that to calculate the parameters of the electrostatic field of the ion crystal lattice it sufficient to take into account ions located at a distance of 1-2 lattice spacings. More distant ions make insignificant contribution. As a result, the electrostatic energy of the ion lattice in the alkaline halide crystal produced by both positive and negative ions is in good agreement with experiment when the melting temperature and the shear modulus are calculated. For fcc and bcc metals the ion lattice electrostatic energy is not sufficient to obtain the observed values of these parameters. It is possible to resolve the contradiction if one assumes that the electron density is strongly localized and has a crystal structure described by the lattice delta - function. As a result, positive charges alternate with negative ones as in the alkaline halide crystal. Such delta-like localization of the electron density is known as a model of nearly free electrons.

  3. Shaped Crystal Growth

    Science.gov (United States)

    Tatartchenko, Vitali A.

    Crystals of specified shape and size (shaped crystals) with controlled crystal growth (SCG) defect and impurity structure have to be grown for the successful development of modern engineering. Since the 1950s many hundreds of papers and patents concerned with shaped growth have been published. In this chapter, we do not try to enumerate the successful applications of shaped growth to different materials but rather to carry out a fundamental physical and mathematical analysis of shaping as well as the peculiarities of shaped crystal structures. Four main techniques, based on which the lateral surface can be shaped without contact with the container walls, are analyzed: the Czochralski technique (CZT), the Verneuil technique (VT), the floating zone technique (FZT), and technique of pulling from shaper (TPS). Modifications of these techniques are analyzed as well. In all these techniques the shape of the melt meniscus is controlled by surface tension forces, i.e., capillary forces, and here they are classified as capillary shaping techniques (CST). We look for conditions under which the crystal growth process in each CST is dynamically stable. Only in this case are all perturbations attenuated and a crystal of constant cross section shaping technique (CST) grown without any special regulation. The dynamic stability theory of the crystal growth process for all CST is developed on the basis of Lyapunov's dynamic stability theory. Lyapunov's equations for the crystal growth processes follow from fundamental laws. The results of the theory allow the choice of stable regimes for crystal growth by all CST as well as special designs of shapers in TPS. SCG experiments by CZT, VT, and FZT are discussed but the main consideration is given to TPS. Shapers not only allow crystal of very complicated cross section to be grown but provide a special distribution of impurities. A history of TPS is provided later in the chapter, because it can only be described after explanation of the

  4. Cross Sections for Neutron-induced Reactions on Actinide Targets Extracted from Surrogate Experiments: A Status Report

    Energy Technology Data Exchange (ETDEWEB)

    Escher, J E; Burke, J T; Dietrich, F S; Lesher, S R; Scielzo, N D; Thompson, I J; Younes, W

    2009-10-01

    The Surrogate nuclear reactions method, an indirect approach for determining cross sections for compound-nuclear reactions involving difficult-to-measure targets, is reviewed. Focusing on cross sections for neutron-induced reactions on actinides, we review the successes of past and present applications of the method and assess its uncertainties and limitations. The approximations used in the analyses of most experiments work reasonably well for (n,f) cross sections for neutron energies above 1-2 MeV, but lead to discrepancies for low-energy (n,f) reactions, as well as for (n,{gamma}) applications. Correcting for some of the effects neglected in the approximate analyses leads to improved (n,f) results. We outline steps that will further improve the accuracy and reliability of the Surrogate method and extend its applicability to reactions that cannot be approached with the present implementation of the method.

  5. Transesterification-crystallization Extraction of Cottonseed Oil Deodorizer Distillate Study on Phytosterol%转酯化-结晶提取棉籽油脱臭馏出物中植物甾醇的研究

    Institute of Scientific and Technical Information of China (English)

    孙静涛; 董娟; 肖婧; 史学伟

    2013-01-01

    本文系统地研究了棉籽油脱臭馏出物中甾醇提取方法,主要得出以下结论:采用转酯化-结晶法对棉籽油脱臭馏出物中甾醇进行萃取,最佳萃取条件为:料液比为1/5 (m/V),转酯化温度为60℃,催化剂使用量为35%,转酯化时间为4h,甾醇提取率为54.80%,甾醇纯度达到82.10%.%A process for extracting plant sterol from cotton oil deodorizer distillate and the crystal purification were studied. The optimal conditions for transesterification of sterol ester were obtained as followed: the rate of blend composition 1/5 (m/V), temperature 60 ℃, the dosage of catalyst 35% and time 4.0 hour. The recovery rate was 54.8% and purity of rough sterol was 82.10%.

  6. Extracting the Beat: An Experience-dependent Complex Integration of Multisensory Information Involving Multiple Levels of the Nervous System

    Directory of Open Access Journals (Sweden)

    Laurel J. Trainor

    2009-04-01

    Full Text Available In a series of studies we have shown that movement (or vestibular stimulation that is synchronized to every second or every third beat of a metrically ambiguous rhythm pattern biases people to perceive the meter as a march or as a waltz, respectively. Riggle (this volume claims that we postulate an "innate", "specialized brain unit" for beat perception that is "directly" influenced by vestibular input. In fact, to the contrary, we argue that experience likely plays a large role in the development of rhythmic auditory-movement interactions, and that rhythmic processing in the brain is widely distributed and includes subcortical and cortical areas involved in sound processing and movement. Further, we argue that vestibular and auditory information are integrated at various subcortical and cortical levels along with input from other sensory modalities, and it is not clear which levels are most important for rhythm processing or, indeed, what a "direct" influence of vestibular input would mean. Finally, we argue that vestibular input to sound location mechanisms may be involved, but likely cannot explain the influence of vestibular input on the perception of auditory rhythm. This remains an empirical question for future research.

  7. Crystal Data

    Science.gov (United States)

    SRD 3 NIST Crystal Data (PC database for purchase)   NIST Crystal Data contains chemical, physical, and crystallographic information useful to characterize more than 237,671 inorganic and organic crystalline materials. The data include the standard cell parameters, cell volume, space group number and symbol, calculated density, chemical formula, chemical name, and classification by chemical type.

  8. Splitting of a high-energy positively-charged particle beam with a bent crystal

    Science.gov (United States)

    Bandiera, L.; Kirillin, I. V.; Bagli, E.; Berra, A.; De Salvador, D.; Guidi, V.; Lietti, D.; Mazzolari, A.; Prest, M.; Shul'ga, N. F.; Sytov, A.; Vallazza, E.

    2017-07-01

    The possibility of high-energy positively-charged particle beam splitting by means of a short bent axially oriented silicon crystal was recently reported in an experiment carried out at CERN SPS H8 extracted line with a 400 GeV/c proton beam. Here, we investigate more deeply such a possibility focusing our attention on the efficiency of beam splitting and its modulation for different crystal-to-beam orientations. New experimental results confirm the possibility of modulating the 400 GeV/c proton beam intensity in different planar channels by adjusting the orientation of the crystal. Furthermore, an analysis of the beam splitting efficiency vs. the curvature of the crystal was carried out through simulation, highlighting that there exists a bending radius for which the efficiency is maximal.

  9. Computer-assisted Crystallization.

    Science.gov (United States)

    Semeister, Joseph J., Jr.; Dowden, Edward

    1989-01-01

    To avoid a tedious task for recording temperature, a computer was used for calculating the heat of crystallization for the compound sodium thiosulfate. Described are the computer-interfacing procedures. Provides pictures of laboratory equipment and typical graphs from experiments. (YP)

  10. Numerical adiabatic potentials of orthorhombic Jahn-Teller effects retrieved from ultrasound attenuation experiments. Application to the SrF2:Cr crystal

    Science.gov (United States)

    Zhevstovskikh, I. V.; Bersuker, I. B.; Gudkov, V. V.; Averkiev, N. S.; Sarychev, M. N.; Zherlitsyn, S.; Yasin, S.; Shakurov, G. S.; Ulanov, V. A.; Surikov, V. T.

    2016-06-01

    A methodology is worked out to retrieve the numerical values of all the main parameters of the six-dimensional adiabatic potential energy surface (APES) of a polyatomic system with a quadratic T-term Jahn-Teller effect (JTE) from the ultrasound experiments. The method is based on a verified assumption that ultrasound attenuation and speed encounter anomalies when the direction of propagation and polarization of its wave of strain coincides with the characteristic directions of symmetry breaking in the JTE. For the SrF2:Cr crystal, employed as a basic example, we observed anomaly peaks in the temperature dependence of attenuation of ultrasound at frequencies of 50-160 MHz in the temperature interval of 40-60 K for the wave propagating along the [110] direction, for both the longitudinal and the shear modes, the latter with two polarizations along the [001] and [1 1 ¯ 0 ] axes, respectively. We show that these anomalies are due to the ultrasound relaxation by the system of non-interacting Cr2+ JT centers with orthorhombic local distortions. The interpretation of the experimental findings is based on the T2 g⊗(eg+t2 g) JTE problem including the linear and the quadratic terms of vibronic interactions in the Hamiltonian and the same-symmetry modes reduced to one interaction mode. Combining the experimental results with a theoretical analysis, we show that on the complicated six-dimensional APES of this system with three tetragonal, four trigonal, and six orthorhombic extrema points, the latter are global minima, while the former are saddle points, and we estimate numerically all the main parameters of this surface, including the linear and quadratic vibronic coupling constants, the primary force constants, the coordinates of all the extrema points and their energies, the energy barrier between the orthorhombic minima, and the tunneling splitting of the ground vibrational states. To our knowledge, such a based-on-experimental-data numerical reconstruction of the APES

  11. Quantitative determination of zero-gravity effects on electronic materials processing germanium crystal growth with simultaneous interface demarcation experiment MA-060, section 5

    Science.gov (United States)

    Gatos, H. C.; Witt, A. F.; Lichtensteiger, M.; Herman, C. J.

    1982-01-01

    The crystal growth and segregation characteristics of a melt in a directional solidification configuration under near zero g conditions were investigated. The germanium (doped with gallium) system was selected because it was extensively studied on Earth and because it lends itself to a very detailed macroscopic and microscopic characterization. An extensive study was performed of the germanium crystals grown during the Apollo-Soyuz Test Project mission. It was found that single crystal growth was achieved and that the interface demarcation functioned successfully. On the basis of the results obtained to date, there is no indication that convection driven by thermal or surface tension gradients was present in the melt. The gallium segregation, in the absence of gravity, was found to be fundamentally different in its initial and its subsequent stages from that of the ground based tests. None of the existing theoretical models for growth and segregation can account for the observed segregation behavior in the absence of gravity.

  12. Polymorph transformation and formation mechanism of calcium carbonate during reactive extraction-crystallization process%反应-萃取-结晶过程制备碳酸钙的晶型转变与结晶机理

    Institute of Scientific and Technical Information of China (English)

    李云钊; 宋兴福; 孙玉柱; 孙泽; 于建国

    2015-01-01

    Distiller waste produced in ammonia-soda process restricts the development of soda industry. In this study, the polymorph transformation and crystallization mechanism of calcium carbonate in the reactive extraction-crystallization coupled process were investigated. The results show that carbon dioxide (CO2) is first absorbed by the organic phase and then transferred to the aqueous phase. Calcium bicarbonate is generated and then decomposed into amorphous calcium carbonate rapidly. Temperature has a significant effect on the polymorph of calcium carbonate. Needle-like aragonite forms preferentially at higher temperatures and spherical and flower-like vaterite forms preferentially at lower temperatures. Both of them will finally transform into rhombic calcite by dissolution and recrystallization. At 20℃, the formation of new vaterite and its transformation to calcite occur simultaneously in the coupled process. The content of vaterite in the particles increases with the increase of CO2 concentration.%氨碱法制碱过程中产生的大量蒸氨废液制约了纯碱工业的发展。本文对反应-萃取-结晶耦合工艺产物碳酸钙的晶型转变和结晶机理进行了研究。结果表明,在此耦合过程中,二氧化碳优先被有机相吸收,然后传递到水相进行反应,首先生成的是碳酸氢钙,之后迅速分解为无定形碳酸钙。温度对碳酸钙晶型影响显著,温度较高时,无定形碳酸钙优先转变为针状文石;温度较低时,无定形碳酸钙优先转变为球状球霰石。随后文石和球霰石均会通过溶解-重结晶作用逐渐转变为稳定的菱形方解石。常温下,反应过程中同时进行着新的球霰石的生成和球霰石转变为方解石两个过程,参与反应的二氧化碳浓度越高,晶体中球霰石的含量越高。

  13. Macromolecular crystallization and crystal perfection

    CERN Document Server

    Chayen, Naomi E; Snell, Edward H

    2010-01-01

    Structural biology is key to our understanding of the mechanisms of biological processes. This text describes current methods and future frontiers in crystal growth and use of X-ray and neutron crystallography, in the context of automation of crystallization and generation of synchrotron X-ray and neutron beams.

  14. Liquid crystal tunable photonic crystal dye laser

    DEFF Research Database (Denmark)

    Buss, Thomas; Christiansen, Mads Brøkner; Smith, Cameron

    2010-01-01

    We present a dye-doped liquid crystal laser using a photonic crystal cavity. An applied electric field to the liquid crystal provides wavelength tunability. The photonic crystal enhances resonant interaction with the gain medium....

  15. Crystal Dislocations

    Directory of Open Access Journals (Sweden)

    Ronald W. Armstrong

    2016-01-01

    Full Text Available Crystal dislocations were invisible until the mid-20th century although their presence had been inferred; the atomic and molecular scale dimensions had prevented earlier discovery. Now they are normally known to be just about everywhere, for example, in the softest molecularly-bonded crystals as well as within the hardest covalently-bonded diamonds. The advent of advanced techniques of atomic-scale probing has facilitated modern observations of dislocations in every crystal structure-type, particularly by X-ray diffraction topography and transmission electron microscopy. The present Special Issue provides a flavor of their ubiquitous presences, their characterizations and, especially, their influence on mechanical and electrical properties.

  16. Crystal growth in salt efflorescence

    Science.gov (United States)

    Zehnder, Konrad; Arnold, Andreas

    1989-09-01

    Salt efflorescences strongly affect wall paintings and other monuments. The external factors governing the crystal habits and aggregate forms are studied phenomenologically in laboratory experiments. As salt contaminated materials dry, slats crystallize forming distinct sequences of crystal habits and aggregate forms on and underneath the surfaces. Four phases may be distinguished: (1) Large individual crystals with equilibrium forms grow immersed in a thick solution film; (2) granular crusts of small isometric crystals grow covered by a thin solution film; (3) fibrous crusts of columnar crystals grow from a coherent but thin solution film so that the crystals are in contact with solution only at their base; (4) whiskers grow from isolated spots of very thin solution films into the air. The main factor governing these morphologies is the humidity of the substrate. A porous material cracks while granular crystals (approaching their equilibrium forms) grow within the large pores. As the fissures widen, the habits pass into columnar crystals and then into whiskers. Because this succession corresponds to the crystallization sequence on the substrate surface it can be traced back to the same growth conditions.

  17. Pressure-Reduction Technique for Crystal Growth

    Science.gov (United States)

    Shlichta, P. J.

    1981-01-01

    Large crystals grown by varying pressure rather than temperature. In constant temerature pressure-reduction process crystal growth promoted as solubility decreases by factor of more than 10. Technique used to study crystal growth kinetics by "pressure wave"" analog of conventional "thermal wave" experiments. Technique has advantages of faster response and freedom from convective interference.

  18. Experimenting with a Visible Copper-Aluminum Displacement Reaction in Agar Gel and Observing Copper Crystal Growth Patterns to Engage Student Interest and Inquiry

    Science.gov (United States)

    Xu, Xinhua; Wu, Meifen; Wang, Xiaogang; Yang, Yangyiwei; Shi, Xiang; Wang, Guoping

    2016-01-01

    The reaction process of copper-aluminum displacement in agar gel was observed at the microscopic level with a stereomicroscope; pine-like branches of copper crystals growing from aluminum surface into gel at a constant rate were observed. Students were asked to make hypotheses on the pattern formation and design new research approaches to prove…

  19. Image processing of 2D crystal images.

    Science.gov (United States)

    Arheit, Marcel; Castaño-Díez, Daniel; Thierry, Raphaël; Gipson, Bryant R; Zeng, Xiangyan; Stahlberg, Henning

    2013-01-01

    Electron crystallography of membrane proteins uses cryo-transmission electron microscopy to image frozen-hydrated 2D crystals. The processing of recorded images exploits the periodic arrangement of the structures in the images to extract the amplitudes and phases of diffraction spots in Fourier space. However, image imperfections require a crystal unbending procedure to be applied to the image before evaluation in Fourier space. We here describe the process of 2D crystal image unbending, using the 2dx software system.

  20. Last crystals for the CMS chandelier

    CERN Multimedia

    2008-01-01

    In March, the last crystals for CMS’s electromagnetic calorimeter arrived from Russia and China. Like dedicated jewellers crafting an immense chandelier, the CMS ECAL collaborators are working extremely hard to install all the crystals before the start-up of the LHC. One of the last CMS end-cap crystals, complete with identification bar code. Lead tungstate crystals mounted onto one section of the CMS ECAL end caps. Nearly 10 years after the first production crystal arrived at CERN in September 1998, the very last shipment has arrived. These final crystals will be used to complete the end-caps of the electromagnetic calorimeter (ECAL) at CMS. All in all, there are more than 75,000 crystals in the ECAL. The huge quantity of CMS lead tungstate crystals used in the ECAL corresponds to the highest volume ever produced for a single experiment. The excellent quality of the crystals, both in ter...

  1. Colloidal nanoparticles trapped by liquid-crystal defect lines: A lattice Monte Carlo simulation

    Science.gov (United States)

    Jose, Regina; Skačej, Gregor; Sastry, V. S. S.; Žumer, Slobodan

    2014-09-01

    Lattice-based Monte Carlo simulations are performed to study a confined liquid crystal system with a topological disclination line entangling a colloidal nanoparticle. In our microscopic study the disclination line is stretched by moving the colloid, as in laser tweezing experiments, which results in a restoring force attempting to minimize the disclination length. From constant-force simulations we extract the corresponding disclination line tension, estimated as ˜50 pN, and observe its decrease with increasing temperature.

  2. Photonic Crystal Microchip Laser

    Science.gov (United States)

    Gailevicius, Darius; Koliadenko, Volodymyr; Purlys, Vytautas; Peckus, Martynas; Taranenko, Victor; Staliunas, Kestutis

    2016-09-01

    The microchip lasers, being very compact and efficient sources of coherent light, suffer from one serious drawback: low spatial quality of the beam strongly reducing the brightness of emitted radiation. Attempts to improve the beam quality, such as pump-beam guiding, external feedback, either strongly reduce the emission power, or drastically increase the size and complexity of the lasers. Here it is proposed that specially designed photonic crystal in the cavity of a microchip laser, can significantly improve the beam quality. Experiments show that a microchip laser, due to spatial filtering functionality of intracavity photonic crystal, improves the beam quality factor M2 reducing it by a factor of 2, and increase the brightness of radiation by a factor of 3. This comprises a new kind of laser, the “photonic crystal microchip laser”, a very compact and efficient light source emitting high spatial quality high brightness radiation.

  3. Spin physics at A Fixed-Target ExpeRiment at the LHC (AFTER@LHC)

    CERN Document Server

    Rakotozafindrabe, A; Arnaldi, R; Brodsky, S J; Chambert, V; Didelez, J P; Ferreiro, E G; Fleuret, F; Genolini, B; Hadjidakis, C; Lansberg, J P; Lorce, C; Rosier, P; Schienbein, I; Scomparin, E; Uggerhoj, U I

    2013-01-01

    We outline the opportunities for spin physics which are offered by a next generation and multi-purpose fixed-target experiment exploiting the proton LHC beam extracted by a bent crystal. In particular, we focus on the study of single transverse spin asymetries with the polarisation of the target.

  4. A time-resolved x-ray scattering experiment for the study of phase transitions and crystallization processes in metallic alloys

    Energy Technology Data Exchange (ETDEWEB)

    Pelletier, J. F.; Sutton, M.; Altounian, Z.; Saini, S.; Luriom L. B.; Sandy, A. R.; Lumma, D.; Borthwick, M. A.; Falus, P.; Mochrie, S. G. J.; Stephenson, G. B.

    1999-10-29

    An experimental setup to perform high-resolution time-resolved X-ray scattering has been commissioned on the side station of beamline 8-ID at the Advanced Photon Source. A Peltier-cooled diode detector array covering an angle range of 20 degrees is mounted on a 4-circle goniometer and is used to temporally resolve X-ray scattering patterns with a resolution up to 10 ms. Metallic ribbon samples can be quickly heated and cooled from temperatures up to 500 C inside a furnace with controllable atmosphere and equipped with a beryllium window. A description of the setup is presented along with actual results showing time-resolved phase transitions and crystallization processes in AlYNi metallic alloys. These results demonstrate the power of this technique to investigate complex crystallization processes as well as the versatility of this time-resolved X-ray scattering spectrometer.

  5. Protein Crystal Growth in Microgravity

    Institute of Scientific and Technical Information of China (English)

    毕汝昌; 桂璐璐; 师珂; 王耀萍; 陈世芝; 韩青; 胡永林; 沈福苓; 牛秀田; 华子谦; 卢光莹; 张健; 李松林; 龚为民; 牛立文; 黄其辰

    1994-01-01

    Protein crystal growth is quite important for the determination of protein structureswhich are essential to the understanding of life at molecular level as well as to the development of molecu-lar biotechnology.The microgravity environment of space is an ideal place to study the complicated pro-tein crystallization and to grow good-quality protein crystals.A number of crystal-growth experiments of10 different proteins were carried out in August,1992 on the Chinese re-entry satellite FSW-2 in spaceusing a tube crystallization equipment made in China.A total of 25 samples from 6 proteins producedcrystals,and the effects of microgravity on protein crystal growth were observed,especially for an acidicphospholipase A2 and henegg-white lysozyme which gave better crystals in space than earth-grown crys-tals in ground control experiments.The results have shown that the microgravity in space favors the im-provement of the size,perfection,morphology and internal order of the grown protein crytals.

  6. Crystal Ball Functional Model

    Science.gov (United States)

    Plotnick, David

    2016-09-01

    The A2 collaboration of the MAinz MIkrotron is dedicated to studying meson production and nucleon structure and behavior via photon scattering. The photons are made via bremsstrahlung process and energy-tagged using the Glasgow Photon tagger. The photon beam then interacts in a variety of targets: cryogenic, polarized or solid state, and scattered particles deposit their energy within the NaI crystals. Scintillators are able to give results on particles energy and time. Events are reconstructed by combining information from the Tagging spectrometer, the Crystal Ball detector, the TAPS forward wall spectrometer, a Cherenkov detector, and multi-wire proportional chambers. To better understand the detector and experimental events, a live display was built to show energies deposited in crystals in real-time. In order to show a range of energies and particles, addressable LEDs that are individually programmable were used. To best replicate the Crystal Ball, 3D printing technology was employed to build a similar highly segmented icosahedron that can hold each LED, creating a 3D representation of what photons see during experiments. The LEDs were controlled via Arduino microcontroller. Finally, we implemented the Experimental Physics and Industrial Control System to grab live event data, and a simple program converts this data in to color and crystal number data that is able to communicate with the Arduino. Using these simple parts, we can better visualize and understand the tools used in nuclear physics. This material is based upon work supported by the National Science Foundation Grant No. IIA-1358175.

  7. Solid crystallization by rapid expansion of supercritical ternary mixtures

    Science.gov (United States)

    Domingo, C.; Wubbolts, F. E.; Rodríguez-Clemente, R.; van Rosmalen, G. M.

    1999-03-01

    The objective of the present work was to examine the effect of a solid entrainer in the RESS-process. A RESS-equipment with two extraction columns running in series was used to perform the experiments. Salicylic acid or phenanthrene was used as a solute and benzoic acid as a cosolute. The presence of the cosolute modifies solid crystal size distribution, since it alters solute solubility in the supercritical phase. Homogeneous solid mixtures are obtained after expansion. Alternatively, if the aim is to precipitate a pure compound, solid-solid separation could be aided by selective adsorption into an adsorbent.

  8. Liquid Crystals

    Science.gov (United States)

    1990-01-01

    Thermochromic liquid crystals, or TLCs, are a type of liquid crystals that react to changes in temperature by changing color. The Hallcrest/NASA collaboration involved development of a new way to visualize boundary layer transition in flight and in wind tunnel testing of aircraft wing and body surfaces. TLCs offered a new and potentially better method of visualizing the boundary layer transition in flight. Hallcrest provided a liquid crystal formulation technique that afforded great control over the sensitivity of the liquid crystals to varying conditions. Method is of great use to industry, government and universities for aerodynamic and hydrodynamic testing. Company's principal line is temperature indicating devices for industrial use, such as non-destructive testing and flaw detection in electric/electronic systems, medical application, such as diagnostic systems, for retail sale, such as room, refrigerator, baby bath and aquarium thermometers, and for advertising and promotion specials. Additionally, Hallcrest manufactures TLC mixtures for cosmetic applications, and liquid crystal battery tester for Duracell batteries.

  9. Purification of natural zeolite-clinoptilolite for medical application-Extraction of lead

    Directory of Open Access Journals (Sweden)

    MAGDALENA TOMASEVIC-CANOVIC

    2005-11-01

    Full Text Available A series of experiments of the leaching of lead and other cations from three samples of natural zeolite–clinoptilolite, (Sample 1–deposit Zlatokop, Vranjska Banja, Serbia and Montenegro; Sample 2–deposit Bala Mare, Romania; Sample 3–Igros near Brus, Serbia and Montenegro using EDTA was conducted. The results of the experiments showed that the extraction efficiencies from the examined samples were different. If a suficiently large amount of EDTA was applied, most of the lead was extracted only from Sample 1–deposit Zlatokop. Similar effects were obtained for the leaching of iron. The differences in the extraction efficiencies may be due to the difference of the of lead and iron species present in the zeolite crystals. The effects of EDTAconcentration and solid/liquid ratio on the extraction of lead, iron and aluminum were studied.

  10. Study of the optical monitoring system of the scintillating crystal involved in the electromagnetic calorimeter of CMS experiment; Etude du systeme de suivi optique des cristaux scintillants du calorimetre electromagnetique de l`experience CMS

    Energy Technology Data Exchange (ETDEWEB)

    Geleoc, M

    1998-09-04

    The prospect of the experimental discovery of the Higgs boson is one of the motivations to build the large hadron collider (LHC). Proton beams will collide and the emitted particles will be detected by ATLAS and CMS equipment. In each detector the electromagnetic calorimeter will allow the characterisation of the 2 photons coming from one of the disintegration channels of the Higgs boson. CMS collaboration has chosen an homogeneous calorimeter fitted with PbWO{sub 4} crystals. Each crystal with its photodetector and its electronic device forms one detection channel. The resolution of the detection channels should not deteriorate all along the operating time. The optical monitoring system of the crystals logs then controls the response of each detection channel in order to allow an accurate calibration of the calorimeter. The optical properties, the resistance to irradiation of PbWO{sub 4} crystals and the modelling of light collection are investigated in this work. The description of the different components of the optical monitoring system highlights the technical difficulties we had to challenge. An experimental testing bench has been set up to study the coupling between the scintillation signal and the signal that feeds the monitoring system, this coupling has been studied under irradiation in the conditions of CMS operating. (A.C.) 94 refs.

  11. Determination of the Antibiotic Oxytetracycline in Commercial Milk by Solid-Phase Extraction: A High-Performance Liquid Chromatography (HPLC) Experiment for Quantitative Instrumental Analysis

    Science.gov (United States)

    Mei-Ratliff, Yuan

    2012-01-01

    Trace levels of oxytetracylcine spiked into commercial milk samples are extracted, cleaned up, and preconcentrated using a C[subscript 18] solid-phase extraction column. The extract is then analyzed by a high-performance liquid chromatography (HPLC) instrument equipped with a UV detector and a C[subscript 18] column (150 mm x 4.6 mm x 3.5 [mu]m).…

  12. Determination of the Antibiotic Oxytetracycline in Commercial Milk by Solid-Phase Extraction: A High-Performance Liquid Chromatography (HPLC) Experiment for Quantitative Instrumental Analysis

    Science.gov (United States)

    Mei-Ratliff, Yuan

    2012-01-01

    Trace levels of oxytetracylcine spiked into commercial milk samples are extracted, cleaned up, and preconcentrated using a C[subscript 18] solid-phase extraction column. The extract is then analyzed by a high-performance liquid chromatography (HPLC) instrument equipped with a UV detector and a C[subscript 18] column (150 mm x 4.6 mm x 3.5 [mu]m).…

  13. Photonic crystals

    CERN Document Server

    Busch, Kurt; Wehrspohn, Ralf B; Föll, Helmut

    2006-01-01

    The majority of the contributions in this topically edited book stems from the priority program SPP 1113 ""Photonische Kristalle"" run by the Deutsche Forschungsgemeinschaft (DFG), resulting in a survey of the current state of photonic crystal research in Germany. The first part of the book describes methods for the theoretical analysis of their optical properties as well as the results. The main part is dedicated to the fabrication, characterization and modeling of two- and three-dimensional photonic crystals, while the final section presents a wide spectrum of applications: gas sensors, micr

  14. Shape Evolution of Detached Bridgman Crystals Grown in Microgravity

    Science.gov (United States)

    Volz, M. P.; Mazuruk, K.

    2015-01-01

    A theory describing the shape evolution of detached Bridgman crystals in microgravity has been developed. A starting crystal of initial radius r0 will evolve to one of the following states: Stable detached gap; Attachment to the crucible wall; Meniscus collapse. Only crystals where alpha plus omega is great than 180 degrees will achieve stable detached growth in microgravity. Results of the crystal shape evolution theory are consistent with predictions of the dynamic stability of crystallization (Tatarchenko, Shaped Crystal Growth, Kluwer, 1993). Tests of transient crystal evolution are planned for ICESAGE, a series of Ge and GeSi crystal growth experiments planned to be conducted on the International Space Station (ISS).

  15. An Apparatus for Growth of Small Crystals From Solutions.

    Science.gov (United States)

    Mitrovic, Mico M.

    1995-01-01

    Describes an apparatus for crystal growth that was designed to study growth kinetics of small crystals from solutions and to obtain crystals of various substances. Describes the use of the apparatus in laboratory practical experiments in the field of crystal growth physics within the course "Solid State Physics". (JRH)

  16. Characterization of gypsum crystals exposed to a high CO{sub 2} concentration fog using x-ray

    Energy Technology Data Exchange (ETDEWEB)

    Carreño-Márquez, I. J. A.; Castillo-Sandoval, I.; Esparza-Ponce, H. E.; Fuentes-Cobas, L.; Montero-Cabrera, M. E., E-mail: elena.montero@cimav.edu.mx [Centro de Investigación en Materiales Avanzados (CIMAV), Miguel de Cervantes 120, Chihuahua, Chih. 31136 (Mexico)

    2015-07-23

    In Chihuahua State, a little town called Naica has the largest gypsum single crystals in the world. The growth of these structures has been described as a long and stable process developed over thousands of years. Due to the change in the environmental conditions, these crystals could suffer alterations on their surface. In this project we study the cause of possible deterioration of the giant crystals and intend to suggest measures for their preservation. For this sake, our first experiment consists on several gypsum crystals that have been subjected in a climate chamber to a fog at high CO{sub 2} concentration and 51 °C for a period of time of six months, extracting two crystals every 15 days. Then the crystals have been characterized through Grazing Incidence X-Ray Diffraction using a diffractometer PanAlytical X’PertPro with two different detectors; Xe-filled proportional detector and a Pixel 3D detector. The results were compared to determine which technique is the most suitable to study the degradation of gypsum single crystals. In the two cases, we have identified only the gypsum phase, but with different crystal plane orientations.

  17. Improved description of the structural and optoelectronic properties of DNA/RNA nucleobase anhydrous crystals: Experiment and dispersion-corrected density functional theory calculations

    Science.gov (United States)

    da Silva, M. B.; Francisco, T. S.; Maia, F. F.; Caetano, E. W. S.; Fulco, U. L.; Albuquerque, E. L.; Freire, V. N.

    2017-08-01

    The development of low cost and environmentally friendly organic electronic/optoelectronic devices has attracted a lot of interest. The integration of DNA and RNA nucleobases to improve the performance of organic light-emitting diodes has been proposed recently [Gomez et al., Sci. Rep. 4, 7105 (2014), 10.1038/srep07105], notwithstanding limited experimental and theoretical information on the optoelectronic properties of DNA/RNA thin films. As a contribution to an improved understanding of DNA/RNA-based devices in the solid state, we have performed in this paper dispersion corrected density functional theory (DFT) and time-dependent DFT (TDDFT) calculations to obtain the optimized geometries, Kohn-Sham band structures and orbitals, charge distribution, optical absorption, Frenkel exciton binding energies, and complex dielectric functions of the five DNA/RNA nucleobase anhydrous crystals, namely cytosine, guanine, adenine, thymine, and uracil. Optical absorption measurements on DNA/RNA nucleobase powders were also performed for comparison with the simulations. An improvement on the local density approximation (LDA) description of the lattice parameter estimates was achieved considering the generalized gradient approach (GGA) with a semiempirical dispersion correction scheme in comparison with structural x-ray data found in the literature. Energy gap correction using the Δ-sol methodology provided a good agreement between theory and experimental estimates from our optical absorption data, greatly surpassing the quality of previous simulations. Effective masses for the carriers were also found, indicating that the guanine crystal as well as the cytosine one (although with some drawbacks) has potential applications in optoelectronics as a direct gap semiconductor, with the other nucleobases presenting either a semiconductor or an insulator character depending on the carrier type. The complex dielectric function exhibits a high degree of anisotropy for different states

  18. Further study of CdWO4 crystal scintillators as detectors for high sensitivity double beta experiments: scintillation properties and pulse-shape discrimination

    CERN Document Server

    Bardelli, L; Bizzeti, P G; Carraresi, L; Danevich, F A; Fazzini, T F; Grinyov, B V; Ivannikova, N V; Kobychev, V V; Kropivyansky, B N; Maurenzig, P R; Nagornaya, L L; Nagorny, S S; Nikolaiko, A S; Pavlyuk, A A; Poda, D V; Solsky, I M; Sopinskyy, M V; Stenin, Y G; Taccetti, F; Tretyak, V I; Vasiliev, Y V; Yurchenko, S S; Stenin, Yu. G.; Vasiliev, Ya. V.

    2006-01-01

    Energy resolution, light yield, non-proportionality in the scintillation response, alpha/beta ratio, pulse shape for gamma rays and alpha particles were studied with CdWO4 crystal scintillators. Some indication for a difference in the emission spectra for gamma rays and alpha particles was observed. No dependence of CdWO4 pulse shape on emission spectrum wavelengths under laser, alpha particles and gamma ray excitation was observed. Dependence of scintillation pulse shape for gamma quanta and alpha particles and pulse-shape discrimination ability on temperature was measured in the range of 0-24 degrees.

  19. Further study of CdWO{sub 4} crystal scintillators as detectors for high sensitivity 2{beta} experiments: Scintillation properties and pulse-shape discrimination

    Energy Technology Data Exchange (ETDEWEB)

    Bardelli, L. [Dipartimento di Fisica, Universita di Firenze and INFN, 50019 Florence (Italy); Bini, M. [Dipartimento di Fisica, Universita di Firenze and INFN, 50019 Florence (Italy); Bizzeti, P.G. [Dipartimento di Fisica, Universita di Firenze and INFN, 50019 Florence (Italy); Carraresi, L. [Dipartimento di Fisica, Universita di Firenze and INFN, 50019 Florence (Italy); Danevich, F.A. [Institute for Nuclear Research, MSP 03680 Kiev (Ukraine)]. E-mail: danevich@kinr.kiev.ua; Fazzini, T.F. [Dipartimento di Fisica, Universita di Firenze and INFN, 50019 Florence (Italy); Grinyov, B.V. [Institute for Scintillation Materials, 61001 Kharkov (Ukraine); Ivannikova, N.V. [Nikolaev Institute of Inorganic Chemistry, 630090 Novosibirsk (Russian Federation); Kobychev, V.V. [Institute for Nuclear Research, MSP 03680 Kiev (Ukraine); Kropivyansky, B.N. [Institute for Nuclear Research, MSP 03680 Kiev (Ukraine); Maurenzig, P.R. [Dipartimento di Fisica, Universita di Firenze and INFN, 50019 Florence (Italy); Nagornaya, L.L. [Institute for Scintillation Materials, 61001 Kharkov (Ukraine); Nagorny, S.S. [Institute for Nuclear Research, MSP 03680 Kiev (Ukraine); Nikolaiko, A.S. [Institute for Nuclear Research, MSP 03680 Kiev (Ukraine); Pavlyuk, A.A. [Nikolaev Institute of Inorganic Chemistry, 630090 Novosibirsk (Russian Federation); Poda, D.V. [Institute for Nuclear Research, MSP 03680 Kiev (Ukraine); Solsky, I.M. [Institute for Materials, 79031 Lviv (Ukraine); Sopinskyy, M.V. [Lashkaryov Institute of Semiconductor Physics, 03028 Kiev (Ukraine); Stenin, Yu.G. [Nikolaev Institute of Inorganic Chemistry, 630090 Novosibirsk (Russian Federation); Taccetti, F. [Dipartimento di Fisica, Universita di Firenze and INFN, 50019 Florence (Italy); Tretyak, V.I.; Yurchenko, S.S. [Institute for Nuclear Research, MSP 03680 Kiev (Ukraine); Vasiliev, Ya.V. [Nikolaev Institute of Inorganic Chemistry, 630090 Novosibirsk (Russian Federation)

    2006-12-21

    Energy resolution, non-proportionality in the scintillation response, {alpha}/{beta} ratio, pulse shape for {gamma} rays and {alpha} particles were studied with CdWO{sub 4} crystal scintillators. Some indication for a difference in the emission spectra for {gamma} rays and {alpha} particles was observed. No dependence of CdWO{sub 4} pulse shape on emission spectrum wavelengths under laser, {alpha} particles and {gamma} ray excitation was observed. Dependence of scintillation pulse shape for {gamma} quanta and {alpha} particles and pulse-shape discrimination ability on temperature was measured in the range of 0-24{sup o}C.

  20. The 3-5 semiconductor solid solution single crystal growth. [low gravity float zone growth experiments using gallium indium antimonides and cadmium tellurides

    Science.gov (United States)

    Gertner, E. R.

    1980-01-01

    Techniques used for liquid and vapor phase epitaxy of gallium indium arsenide are described and the difficulties encountered are examined. Results show that the growth of bulk III-V solid solution single crystals in a low gravity environment will not have a major technological impact. The float zone technique in a low gravity environment is demonstrated using cadmium telluride. It is shown that this approach can result in the synthesis of a class of semiconductors that can not be grown in normal gravity because of growth problems rooted in the nature of their phase diagrams.

  1. PERMCAT experiments with tritium at high helium flow rates relevant for the tritium extraction systems using the CAPER facility at TLK

    Energy Technology Data Exchange (ETDEWEB)

    Bükki-Deme, András, E-mail: andras.buekki-deme@kit.edu; Demange, David; Le, Thanh-Long; Fanghänel, Eleonore; Simon, Karl-Heinz

    2016-11-01

    Highlights: • We examined PERMCAT reactor efficiency processing tritiated water at high Helium carrier flow rates. • We have found that – as expected from previous studies – that the swamping ratio (ratio between the impurity and purge side flow rates) has a key effect on the decontamination factors. • On the other hand, some rather unexpected effects tend to show that the limiting phenomena of such specific operation of PERMCAT reactors (at high impurity flow rates, thus short residence time) lies on the kinetics of the isotope exchange reactions. - Abstract: Experiments are still necessary to consolidate the processes retained for the Tritium Extraction Systems of the European ITER Test Blanket Modules (TBM). A PERMCAT reactor combines a catalyst promoting isotope exchange reactions and a Pd/Ag membrane allowing tritium recovery from complex gaseous mixtures containing tritium in different chemical forms. Originally developed for the Tokamak Exhaust Processing, the PERMCAT process is also candidate to detritiate the water arising from an adsorption column installed in the TBM ancillary systems. We discuss the results of an extensive experimental campaign using a PERMCAT reactor to process Q{sub 2}O containing impurity gas mixtures at high flow rates. Two different experimental configurations were studied, namely PERMCAT stand-alone, and PERMCAT in combination with a zeolite molecular sieve bed (MSB, previously loaded with Q{sub 2}O) under regeneration. On the one hand, many expected behaviors were observed, such as the key influence of the swamping ratio (ratio between the impurity and purge side flow rates) on the decontamination factors. On the other hand, some rather unexpected effects tend to show that the limiting phenomena of such specific operation of PERMCAT reactors (at high flow rates, thus short residence time) lies on the kinetics of the isotope exchange reactions.

  2. Ribbon Crystals

    DEFF Research Database (Denmark)

    Bohr, Jakob; Markvorsen, Steen

    2013-01-01

    A repetitive crystal-like pattern is spontaneously formed upon the twisting of straight ribbons. The pattern is akin to a tessellation with isosceles triangles, and it can easily be demonstrated with ribbons cut from an overhead transparency. We give a general description of developable ribbons...

  3. Therapeutic Crystals

    Science.gov (United States)

    Bond, Charles S.

    2014-01-01

    Some readers might not fully know what the difference is between crystallography, and the "new age" practice of dangling crystals around the body to capitalise on their healing energy. The latter is often considered to be superstition, while ironically, the former has actually resulted in real rationally-based healing of human diseases…

  4. 正交试验优选罗勒子中总黄酮的提取工艺%Optimization of Extract Technology of Total Favonoids in Seme Ocimum Basilicum by Orthogonal Experiment

    Institute of Scientific and Technical Information of China (English)

    谢晶; 孙莲

    2014-01-01

    目的:优选罗勒子中总黄酮的提取工艺。方法以芦丁为标准品,通过紫外分光光度法测定罗勒子中总黄酮含量,通过单因素试验和正交试验考察不同因素和水平对提取工艺的影响。结果甲醇浓度对罗勒子中总黄酮含量影响最大,其他三个因素对样品含量的影响大小依次是:料液比>提取次数>提取时间。结论最佳提取工艺条件为甲醇浓度80%,固液比1∶10,提取1h,提取1次。%Objective To optimize the extract technology of the total favonoids from the fruit of ocimum basilicum. Methods Determination of total favonoids in fruit of ocimum basilicum by UV, the content of favonoids was computed with rutin as standard substance, and the influence of different factors and levels on the extract technology were investigated by means of simple factor experiment and orthogonal experiment. Results Methanol concentration had great impact on the target. The order of the other 3 factors that affected the lfavonoid extractions was amount of ethanol>number of extractions>extraction time. Conclusion The optimum extraction technology was as follows: 80% Methanol concentration 10 times the weight of the dried material, relfux extracting total favonoids once, 1 h at each time.

  5. Photonic crystals principles and applications

    CERN Document Server

    Gong, Qihuang

    2013-01-01

    IntroductionPrimary Properties of Photonic CrystalsFabrication of Photonic CrystalsPhotonic Crystal All-Optical SwitchingTunable Photonic Crystal FilterPhotonic Crystal LaserPhotonic Crystal Logic DevicesPhotonic Crystal Sensors

  6. Extraction of Fast Changes in the Structure of a Disordered Ensemble of Photoexcited Biomolecules

    Directory of Open Access Journals (Sweden)

    H.-C. Poon

    2013-01-01

    Full Text Available Using pump-probe experiments of varying time intervals between pump and probe, the method of time-resolved crystallography has given many insights into the fast time variations of crystallized molecules as a result of photoexcitation. We show here that quantities extractable from multiple diffraction patterns of dissolved molecules in random orientations, as measured using powerful ultrashort pulses of X-rays, also contain information about structural changes of a molecule on photoexcitation.

  7. Antihistomonal effects of artemisinin and Artemisia annua extracts in vitro could not be confirmed by in vivo experiments in turkeys and chickens

    DEFF Research Database (Denmark)

    Thøfner, I.C.N.; Liebhart, D.; Hess, M.;

    2012-01-01

    Five different Artemisia annua-derived materials (i.e. dry leaves, pure artemisinin, and hexane, dichloromethane or methanol extracts of leaves) were screened for their in vitro activities against six clonal cultures of Histomonas meleagridis. Except for the methanol extract, all tested materials....... The dichloromethane extract of dry leaves (Ext-DCM) (minimal lethal concentration1.0 mg/ml) and artemisinin (half-maximal inhibitory concentration1.295 mg/ml) had the most promising antihistomonal properties and were therefore subsequently tested in a standardized experimental infection model in both turkeys...

  8. Cirrus Crystal Terminal Velocities.

    Science.gov (United States)

    Heymsfield, Andrew J.; Iaquinta, Jean

    2000-04-01

    Cirrus crystal terminal velocities are of primary importance in determining the rate of transport of condensate from upper- to middle-tropospheric levels and profoundly influence the earth's radiation balance through their effect on the rate of buildup or decay of cirrus clouds. In this study, laboratory and field-based cirrus crystal drag coefficient data, as well as analytical descriptions of cirrus crystal shapes, are used to derive more physically based expressions for the velocities of cirrus crystals than have been available in the past.Polycrystals-often bullet rosettes-are shown to be the dominant crystal types in synoptically generated cirrus, with columns present in varying but relatively large percentages, depending on the cloud. The two critical parameters needed to calculate terminal velocity are the drag coefficient and the ratio of mass to cross-sectional area normal to their fall direction. Using measurements and calculations, it is shown that drag coefficients from theory and laboratory studies are applicable to crystals of the types found in cirrus. The ratio of the mass to area, which is shown to be relatively independent of the number of bullets in the rosette, is derived from an analytic model that represents bullet rosettes containing one to eight bullets in 19 primary geometric configurations. The ratio is also derived for columns. Using this information, a general set of equations is developed to calculate the terminal velocities and masses in terms of the aspect ratio (width divided by length), ice density, and rosette maximum dimension. Simple expressions for terminal velocity and mass as a function of bullet rosette maximum dimension are developed by incorporating new information on bullet aspect ratios.The general terminal velocity and mass relations are then applied to a case from the First International Satellite Cloud Climatology Project (ISCCP) Research Experiment (FIRE) 2, when size spectra from a balloon-borne ice crystal

  9. The CMS crystal calorimeter

    CERN Document Server

    Lustermann, W

    2004-01-01

    The measurement of the energy of electrons and photons with very high accuracy is of primary importance far the study of many physics processes at the Large Hadron Collider (LHC), in particular for the search of the Higgs Boson. The CMS experiment will use a crystal calorimeter with pointing geometry, almost covering 4p, as it offers a very good energy resolution. It is divided into a barrel composed of 61200 lead tungstate crystals, two end-caps with 14648 crystals and a pre-shower detector in front of the end-cap. The challenges of the calorimeter design arise from the high radiation environment, the 4 Tesla magnetic eld, the high bunch crossing rate of 40 MHz and the large dynamic range, requiring the development of fast, radiation hard crystals, photo-detectors and readout electronics. An overview of the construction and design of the calorimeter will be presented, with emphasis on some of the details required to meet the demanding performance goals. 19 Refs.

  10. Final results of an experiment to search for 2beta processes in zinc and tungsten with the help of radiopure ZnWO4 crystal scintillators

    CERN Document Server

    Belli, P; Cappella, F; Cerulli, R; Danevich, F A; d'Angelo, S; Incicchitti, A; Kobychev, V V; Poda, D V; Tretyak, V I

    2011-01-01

    A search for the double beta decay of zinc and tungsten isotopes has been performed with the help of radiopure ZnWO4 crystal scintillators (0.1-0.7 kg) at the Gran Sasso National Laboratories of the INFN. The total exposure of the low background measurements is 0.529 kg yr. New improved half-life limits on the double beta decay modes of 64Zn, 70Zn, 180W, and 186W have been established at the level of 10^{18}-10^{21} yr. In particular, limits on double electron capture and electron capture with positron emission in 64Zn have been set: T_{1/2}(2\

  11. Experiment Research of Extracting Iron from Bayer Red Mud by Magnetic Separation Equipment%永磁法赤泥选铁的试验研究

    Institute of Scientific and Technical Information of China (English)

    邓琦; 张冬梅

    2012-01-01

    Red mud is the residue in alumina production process. With the rapid development of alumina industry, its emissions are growing rapidly. At present, both at home and abroad, red mud is wet stored in most alumina plant. More yard construction and maintenance fees are cost and its strong alkalis make the soil more alkaline. As the surface and underground water are polluted and the ecological environment is harmed directly or indirectly, the comprehensive utilization of iron from red mud has become a worldwide problem. In order to reduce the waste of red mud and thoroughly recycle the iron minerals in it, the extraction of iron from red mud by magnetic separation equipment was tested through experiments. According to the characteristics of the minerals in red mud, high-gradient magnetic separation equipment with a permanent magnet was chosen for extracting iron from red mud. The operation mode of the equipment, the working frequency of the magnetic roller, the opening scale of the magnetic equipment, the flushing area, and other influencing factors were studied. Continuous small-scale industrial test under optimal conditions was done. And the results of the test show that: the iron separation efficiency of high magnetic material Fe2O3 is 69.28%, and the recovery rates of red mud and Fe2O3 are 24.96% and 58.12%, respectively.%赤泥是氧化铝生产过程中铝土矿经强碱浸出后所产生的废渣.随着氧化铝工业的高速发展,其排放量增长很快.目前国内外氧化铝厂大都将赤泥筑坝湿法堆存,耗费较多的堆场建设和维护费用,而且其强碱性、高盐度造成土壤严重碱化,污染地表及地下水源,对生态环境造成直接或间接的危害,其综合利用已成为世界性的难题.为了减少赤泥的外排量,综合回收赤泥中的铁矿物,本研究对拜耳法赤泥进行了永磁法选铁的工艺试验研究.针对赤泥矿物成分的特点,选用了高梯度永磁体磁选设备进行赤泥选铁,研究

  12. Amorphous silicon crystallization by laser. Report of the experiments at Frascati (Project Foto); Cristallizzazione di silicio amorfo via laser. Rapporto degli esperimenti a frascati (Progetto Foto)

    Energy Technology Data Exchange (ETDEWEB)

    Bollanti, S.; Di Lazzaro, P.; Murra, D. [ENEA, Centro Ricerche Frascati, Frascati, RM (Italy). Div. Fisica Applicata; Imparato, A.; Privato, C. [ENEA, Centro Ricerche Portici, Naples (Italy). Div. Fonti Rinnovabili; Carluccio, R.; Fortunato, G.; Mariucci, L.; Pecora, A. [CNR Istituto di Elettronica dello Stato Solido, Rome (Italy)

    2000-07-01

    The final goal of the Project FOTO is the construction of a laboratory in a clean room for the production of active matrix which can be used to obtain Active Matrix Liquid Crystal Displays (AMLCD). The AMLCD are based on Thin Film Transistors (TFT), which can be obtained by poly-silicon (poly-Si) thin films, achieved, e.g., by irradiating films of amorphous silicon (a-Si) by ultraviolet laser radiation. In this report, are presented the results of the a-Si irradiation by using the laser-facility Hercules (excimer XeCl, l=0,308 mm) done at the ENEA Frascati Centre. The transformation of a-Si into poly-Si is commented upon the variation of the space-time characteristics of the laser pulses, of the irradiation conditions and of the characteristics of the irradiated a-Si films. [Italian] Il macro-obiettivo del Progetto FOTO e' la realizzazione di un laboratorio in camera pulita per lo sviluppo di processi atti a fabbricare matrici attive utilizzabili per ottenere schermi piatti a cristalli liquidi (AMLCD, Active Matrix Liquid Crystal Display). Uno dei primi passi del processo consiste nel creare transistori a film sottile (TFT, Thin Film Transistor). A tal fine, e' necessario ottenere strati sottili di Silicio policristallino irragiando films di silicio amorfo con luce laser ultravioletta. In questo rapporto, sono presentati i risultati degli irraggiamenti di film sottili di silicio amorfo tramite la laser-facility Hercules (eccimero XeCl, l=0,308 mm) effettuati presso il C.R. ENEA di Frascati. La trasformazione di silicio amorfo in silicio policristallino cosi' ottenuta e' commentata al variare delle caratteristiche spazio-temporali dell'impulso laser, delle condizioni di irraggiamento e delle caratteristiche del film di silicio amorfo irraggiato.

  13. 正交试验优选紫草凝胶提取工艺%Optimization of the Extraction Technology of Radix Arnebiae Gel by Orthogonal Experiment

    Institute of Scientific and Technical Information of China (English)

    刘万华; 刘洁

    2011-01-01

    OBJECTIVE: To optimize the extraction technology of Radix Arnebiae gel.METHODS: Orthogonal design was carried out to optimize the extraction technology of Radix Arnebiae gel using the concentration and amount of ethanol and extraction time as factors and using the content of shikonin as index.RESULTS: The optimal extracting technology was as follows: 16-folds 95% alcohol for 3 hours.The content of L-shikonin was 5.672 mg·g-1.CONCLUSION: The extraction of L-shikonin is stable and feasible for the extraction of Radix Arnebiae from Radix Arnebiae gel.%目的:优选紫草凝胶中紫草的提取工艺.方法:以乙醇浓度、乙醇用量、浸出时问为考察因素,以左旋紫草素含量为评价指标,采用正交试验优选紫草凝胶中紫草的提取工艺.结果:优选的工艺为用16倍药材量的95%乙醇提取3h,左旋紫草素含量为5.672 mg·g-1药材.结论:该工艺稳定、可行,可用于紫草凝胶中紫草的提取.

  14. Extracting oil using carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Torok, J.

    1984-01-01

    Special literature is the basis for a brief characterization of a method for extracting oil using CO2 and for generalizing the basic results of physical and chemical experiments, as well as displacement experiments conducted in laboratory conditions.

  15. Sample Preparation and Extraction in Small Sample Volumes Suitable for Pediatric Clinical Studies: Challenges, Advances, and Experiences of a Bioanalytical HPLC-MS/MS Method Validation Using Enalapril and Enalaprilat

    Directory of Open Access Journals (Sweden)

    Bjoern B. Burckhardt

    2015-01-01

    Full Text Available In USA and Europe, medicines agencies force the development of child-appropriate medications and intend to increase the availability of information on the pediatric use. This asks for bioanalytical methods which are able to deal with small sample volumes as the trial-related blood lost is very restricted in children. Broadly used HPLC-MS/MS, being able to cope with small volumes, is susceptible to matrix effects. The latter restrains the precise drug quantification through, for example, causing signal suppression. Sophisticated sample preparation and purification utilizing solid-phase extraction was applied to reduce and control matrix effects. A scale-up from vacuum manifold to positive pressure manifold was conducted to meet the demands of high-throughput within a clinical setting. Faced challenges, advances, and experiences in solid-phase extraction are exemplarily presented on the basis of the bioanalytical method development and validation of low-volume samples (50 μL serum. Enalapril, enalaprilat, and benazepril served as sample drugs. The applied sample preparation and extraction successfully reduced the absolute and relative matrix effect to comply with international guidelines. Recoveries ranged from 77 to 104% for enalapril and from 93 to 118% for enalaprilat. The bioanalytical method comprising sample extraction by solid-phase extraction was fully validated according to FDA and EMA bioanalytical guidelines and was used in a Phase I study in 24 volunteers.

  16. 参政邹尧臣生平及其家世考%Research on ZOU Yaochen's Life Experiences and Family Extraction

    Institute of Scientific and Technical Information of China (English)

    郭磊; 何邦华

    2012-01-01

    The Inscriptional Records on the Establishment of School Farm System by Assistant administrator ZOU Yaochen is an important historical materials for the study on the cultural and educational development in Yunnan border area in Ming Dynasty. The school farm system in Zhaozhou (named Fengyi in Dali today) existed more than 400 years in history until it was abolished in Land Reform after 1949 and exerted far-reaching influence on the cultural and educational development in Fengyi, Dali. However, little is known about ZOU Yaochen, the founder of the system. ZOU Yaochen, being a Jinshi, (examinee passing through palace examination), successively served as Ynshi (provincial censor), Fnshi (vice-minister) and Canzheng (assistant administrator) and resided in Dali after his retired age. As an important local official in Dali, ZOU Yaochen acquired remarkable effect in incorruption and serving the people, and he is a famous historical figure who had higher prestige and reputation in local society. The records of his life experiences are dispersedly found in official history, chronicles, inscriptions and genealogy, lacking of systematic organization, reliable collation, comprehensive textual research and detailed research. In this paper, the author will make a research on his life experiences and family extraction, based on available historical records and field researches.%《参政邹尧臣置学田碑记》是研究明代云南边疆文化教育发展的重要史料,赵州学田制度沿用400多年,直至解放后土改时才停止,为大理凤仪地区文化教育发展发挥了久远的作用,但是创立赵州学田制度的邹尧臣的生平事迹长期为人们所忽视。邹尧臣进士出身,官拜御史、副使、参政等要职,中晚年归根云南赵州(今大理凤仪),他不仅是当地的官宦大家,且为民清政多有贡献,是当地名望极高颇具影响的著名历史人物。其生平事迹散见于正史、方志、碑刻

  17. Impact of ultrasound on solid-liquid extraction of phenolic compounds from maritime pine sawdust waste. Kinetics, optimization and large scale experiments.

    Science.gov (United States)

    Meullemiestre, A; Petitcolas, E; Maache-Rezzoug, Z; Chemat, F; Rezzoug, S A

    2016-01-01

    Maritime pine sawdust, a by-product from industry of wood transformation, has been investigated as a potential source of polyphenols which were extracted by ultrasound-assisted maceration (UAM). UAM was optimized for enhancing extraction efficiency of polyphenols and reducing time-consuming. In a first time, a preliminary study was carried out to optimize the solid/liquid ratio (6g of dry material per mL) and the particle size (0.26 cm(2)) by conventional maceration (CVM). Under these conditions, the optimum conditions for polyphenols extraction by UAM, obtained by response surface methodology, were 0.67 W/cm(2) for the ultrasonic intensity (UI), 40°C for the processing temperature (T) and 43 min for the sonication time (t). UAM was compared with CVM, the results showed that the quantity of polyphenols was improved by 40% (342.4 and 233.5mg of catechin equivalent per 100g of dry basis, respectively for UAM and CVM). A multistage cross-current extraction procedure allowed evaluating the real impact of UAM on the solid-liquid extraction enhancement. The potential industrialization of this procedure was implemented through a transition from a lab sonicated reactor (3 L) to a large scale one with 30 L volume.

  18. Tooth extraction

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/007630.htm Tooth extraction To use the sharing features on this page, please enable JavaScript. A tooth extraction is a procedure to remove a tooth from ...

  19. Crystallization experiments with the dinuclear chelate ring complex di-μ-chlorido-bis[(η(2)-2-allyl-4-methoxy-5-{[(propan-2-yloxy)carbonyl]methoxy}phenyl-κC(1))platinum(II)].

    Science.gov (United States)

    Nguyen Thi Thanh, Chi; Pham Van, Thong; Le Thi Hong, Hai; Van Meervelt, Luc

    2016-10-01

    Crystallization experiments with the dinuclear chelate ring complex di-μ-chlorido-bis[(η(2)-2-allyl-4-methoxy-5-{[(propan-2-yloxy)carbonyl]methoxy}phenyl-κC(1))platinum(II)], [Pt2(C15H19O4)2Cl2], containing a derivative of the natural compound eugenol as ligand, have been performed. Using five different sets of crystallization conditions resulted in four different complexes which can be further used as starting compounds for the synthesis of Pt complexes with promising anticancer activities. In the case of vapour diffusion with the binary chloroform-diethyl ether or methylene chloride-diethyl ether systems, no change of the molecular structure was observed. Using evaporation from acetonitrile (at room temperature), dimethylformamide (DMF, at 313 K) or dimethyl sulfoxide (DMSO, at 313 K), however, resulted in the displacement of a chloride ligand by the solvent, giving, respectively, the mononuclear complexes (acetonitrile-κN)(η(2)-2-allyl-4-methoxy-5-{[(propan-2-yloxy)carbonyl]methoxy}phenyl-κC(1))chloridoplatinum(II) monohydrate, [Pt(C15H19O4)Cl(CH3CN)]·H2O, (η(2)-2-allyl-4-methoxy-5-{[(propan-2-yloxy)carbonyl]methoxy}phenyl-κC(1))chlorido(dimethylformamide-κO)platinum(II), [Pt(C15H19O4)Cl(C2H7NO)], and (η(2)-2-allyl-4-methoxy-5-{[(propan-2-yloxy)carbonyl]methoxy}phenyl-κC(1))chlorido(dimethyl sulfoxide-κS)platinum(II), determined as the analogue {η(2)-2-allyl-4-methoxy-5-[(ethoxycarbonyl)methoxy]phenyl-κC(1)}chlorido(dimethyl sulfoxide-κS)platinum(II), [Pt(C14H17O4)Cl(C2H6OS)]. The crystal structures confirm that acetonitrile interacts with the Pt(II) atom via its N atom, while for DMSO, the S atom is the coordinating atom. For the replacement, the longest of the two Pt-Cl bonds is cleaved, leading to a cis position of the solvent ligand with respect to the allyl group. The crystal packing of the complexes is characterized by dimer formation via C-H...O and C-H...π interactions, but no π-π interactions are observed despite the presence of

  20. Biased liquid crystal infiltrated photonic bandgap fiber

    DEFF Research Database (Denmark)

    Weirich, Johannes; Lægsgaard, Jesper; Scolari, Lara

    2009-01-01

    A simulation scheme for the transmission spectrum of a photonic crystal fiber infiltrated with a nematic liquid crystal and subject to an external bias is presented. The alignment of the biased liquid crystal is simulated using the finite element method to solve the relevant system of coupled...... partial differential equations. From the liquid crystal alignment the full tensorial dielectric permittivity in the capillaries is derived. The transmission spectrum for the photonic crystal fiber is obtained by solving the generalized eigenvalue problem deriving from Maxwell’s equations using a vector...... element based finite element method. We demonstrate results for a splay aligned liquid crystal infiltrated into the capillaries of a four-ring photonic crystal fiber and compare them to corresponding experiments....

  1. The MORPHEUS II protein crystallization screen.

    Science.gov (United States)

    Gorrec, Fabrice

    2015-07-01

    High-quality macromolecular crystals are a prerequisite for the process of protein structure determination by X-ray diffraction. Unfortunately, the relative yield of diffraction-quality crystals from crystallization experiments is often very low. In this context, innovative crystallization screen formulations are continuously being developed. In the past, MORPHEUS, a screen in which each condition integrates a mix of additives selected from the Protein Data Bank, a cryoprotectant and a buffer system, was developed. Here, MORPHEUS II, a follow-up to the original 96-condition initial screen, is described. Reagents were selected to yield crystals when none might be observed in traditional initial screens. Besides, the screen includes heavy atoms for experimental phasing and small polyols to ensure the cryoprotection of crystals. The suitability of the resulting novel conditions is shown by the crystallization of a broad variety of protein samples and their efficiency is compared with commercially available conditions.

  2. Crystallization of proteins from crude bovine rod outer segments.

    Science.gov (United States)

    Baker, Bo Y; Gulati, Sahil; Shi, Wuxian; Wang, Benlian; Stewart, Phoebe L; Palczewski, Krzysztof

    2015-01-01

    Obtaining protein crystals suitable for X-ray diffraction studies comprises the greatest challenge in the determination of protein crystal structures, especially for membrane proteins and protein complexes. Although high purity has been broadly accepted as one of the most significant requirements for protein crystallization, a recent study of the Escherichia coli proteome showed that many proteins have an inherent propensity to crystallize and do not require a highly homogeneous sample (Totir et al., 2012). As exemplified by RPE65 (Kiser, Golczak, Lodowski, Chance, & Palczewski, 2009), there also are cases of mammalian proteins crystallized from less purified samples. To test whether this phenomenon can be applied more broadly to the study of proteins from higher organisms, we investigated the protein crystallization profile of bovine rod outer segment (ROS) crude extracts. Interestingly, multiple protein crystals readily formed from such extracts, some of them diffracting to high resolution that allowed structural determination. A total of seven proteins were crystallized, one of which was a membrane protein. Successful crystallization of proteins from heterogeneous ROS extracts demonstrates that many mammalian proteins also have an intrinsic propensity to crystallize from complex biological mixtures. By providing an alternative approach to heterologous expression to achieve crystallization, this strategy could be useful for proteins and complexes that are difficult to purify or obtain by recombinant techniques.

  3. Characteristics of tomato plants treated with leaf extracts of neem (Azadirachta indica A. Juss. (L.)) and mata-raton (Gliricidia sepium (Jacquin)): a greenhouse experiment.

    Science.gov (United States)

    Montes-Molina, Joaquín Adolfo; Nuricumbo-Zarate, Ibis Harumy; Hernández-Díaz, Javier; Gutiérrez-Miceli, Federico Antonio; Dendooven, Luc; Ruíz-Valdiviezo, Víctor Manuel

    2014-09-01

    Extracts of neem (Azadirachta indica A.) and mata-raton (Gliricidia sepium) leaves were used as insect repellent during organic cultivation of tomato plants (Solanum lycopersicum) and were compared with untreated plants or plants treated with lambda-cyhalothrin (chemical treatment). The best developed tomato plants were found in the Gliricidia treatment, while difference between other treatments were small. The number of different species of macrofauna found on tomato plants were similar in different treatments, except for corn rootworm (Diabrotica spp.) found in the Gliricidia treatment, but not in other treatments. It was found that leaf extract of G. sepium stimulated tomato growth and altered the leaf and fruit characteristics. This was most likely due to its action as a growth regulator and/or an inductor of changes in the tomato growth regulation, but not due to its action as an insect repellent. Consequently, leaf extract of G. sepium could be used to stimulate tomato development.

  4. Radiating dipoles in photonic crystals

    Science.gov (United States)

    Busch; Vats; John; Sanders

    2000-09-01

    The radiation dynamics of a dipole antenna embedded in a photonic crystal are modeled by an initially excited harmonic oscillator coupled to a non-Markovian bath of harmonic oscillators representing the colored electromagnetic vacuum within the crystal. Realistic coupling constants based on the natural modes of the photonic crystal, i.e., Bloch waves and their associated dispersion relation, are derived. For simple model systems, well-known results such as decay times and emission spectra are reproduced. This approach enables direct incorporation of realistic band structure computations into studies of radiative emission from atoms and molecules within photonic crystals. We therefore provide a predictive and interpretative tool for experiments in both the microwave and optical regimes.

  5. Experiences with archived raw diffraction images data: capturing cisplatin after chemical conversion of carboplatin in high salt conditions for a protein crystal

    NARCIS (Netherlands)

    Tanley, S.W.M.; Diederichs, K.; Kroon-Batenburg, L.M.J.; Schreurs, A.M.M.; Helliwell, J.R.

    2013-01-01

    The archiving of raw diffraction images data is the focus of an IUCr Diffraction Data Deposition Working Group (see http://forums.iucr.org/). Experience in archiving and sharing of raw diffraction images data in collaboration between Manchester and Utrecht Universities, studying the binding of the i

  6. Calibration and monitoring for crystal calorimetry

    CERN Document Server

    Zhu, Ren Yuan

    2005-01-01

    Crystal calorimetry provides excellent energy resolution in high energy and nuclear physics. The light output of heavy crystal scintillators, however, suffers from not negligible damage in radiation environment. A precision calibration and monitoring thus is crucial for maintaining crystal precision in situ. The performance of calibration and monitoring approaches used by BaBar, CLEO and L3 experiments are presented. The design and construction of a laser- based light monitoring system for CMS PWO calorimeter is also discussed.

  7. Optimizing Crystal Volume for Neutron Diffraction Studies

    Science.gov (United States)

    Snell, E. H.

    2003-01-01

    For structural studies with neutron diffraction more intense neutron sources, improved sensitivity detector and larger volume crystals are all means by which the science is being advanced to enable studies on a wider range of samples. We have chosen a simplistic approach using a well understood crystallization method, with minimal amounts of sample and using design of experiment techniques to maximize the crystal volume all for minimum effort. Examples of the application are given.

  8. Optimization Experiment to Extract Citronellol from Pelargonium graveolens with Ethanol%利用乙醇提取香叶天竺葵中香茅醇研究

    Institute of Scientific and Technical Information of China (English)

    陈鹏; 谭乐和; 徐飞; 刘向阳; 郝朝运; 吴刚; 张翠玲

    2012-01-01

    本文利用香叶天竺葵的叶片,对香叶天竺葵中香茅醇的提取率进行研究.对提取香茅醇的最适乙醇浓度、温度、时间、料液比分别进行了测定.结果表明,乙醇提取法的最佳工艺条件为乙醇浓度75%、温度40℃、时间4h、料液比1:20的最佳组合,在该条件下香茅醇提取率可达0.88 mg/g.%The extraction rate of citronellol from leaves of Pelargonium graveolens were determined. The optimum ethanol concentration, temperature, time, and solid-liquid ratio for extracting the citronellol were examined. The results of statistical analysis showed that the ideal extraction condition was as follows; 75 % ethanol concentration, 40℃, 4 h, and 1:20 of the solid-liquid ratio. Under this condition, the extraction rate of citronellol from leaves of Pelargonium graveolens was 0.88 mg/g.

  9. Analyzing the antibacterial effects of food ingredients : model experiments with allicin and garlic extracts on biofilm formation and viability of Staphylococcus epidermidis

    NARCIS (Netherlands)

    Wu, Xueqing; Santos, Regiane R; Fink-Gremmels, Johanna

    2015-01-01

    To demonstrate different effects of garlic extracts and their main antibiotic substance allicin, as a template for investigations on the antibacterial activity of food ingredients. Staphylococcus epidermidis ATCC 12228 and the isogenic biofilm-forming strain ATCC 35984 were used to compare the activ

  10. New design of experiment combined with UV-Vis spectroscopy for extraction and estimation of polyphenols from Basil seeds, Red seeds, Sesame seeds and Ajwan seeds

    Science.gov (United States)

    Mabood, Fazal; Gilani, Syed Abdullah; Hussain, Javid; Alshidani, Sulaiman; Alghawi, Said; Albroumi, Mohammed; Alameri, Saif; Jabeen, Farah; Hussain, Zahid; Al-Harrasi, Ahmed; Al Abri, Zahra K. M.; Farooq, Saima; Naureen, Zakira; Hamaed, Ahmad; Rasul Jan, M.; Shah, Jasmin

    2017-05-01

    New experimental designs for the extraction of polyphenols from different seeds including Basil seed, Red seed, Sesame seeds and Ajwan seeds were investigated. Four variables the concentration and volume of methanol and NaOH solutions as well as the temperature and time of extraction were varied to see their effect on total phenol extraction. The temperature was varied in the range from 25 °C to 200 °C while the time in the range from 30 to 200 minutes. Response surface methodology was used to optimize the extraction parameters. The estimation of polyphenols was measured through phenols reduction UV-Vis spectroscopic method of phosphotungstic-phosphomolybdic acids (Folin-Ciocalteu's reagent). Calibration curve was made by using tannic acid as a polyphenols standard in the concentration range from 0.1 to 10 ppm. The regression line obtained shows the value of correlation coefficient i.e. R = 0.930 and Root mean square error of cross validation (RMSEC) value of 0.0654. The Basil seeds were found containing the highest amount of total phenols i.e. 785.76 mg/100 g. While the Sesame seeds having the least amount i.e. 33.08 mg/100 g. The Ajwan seeds and the Red seeds are containing the medium amounts i.e. 379 mg/100 g and 220.54 mg/100 g respectively.

  11. New design of experiment combined with UV-Vis spectroscopy for extraction and estimation of polyphenols from Basil seeds, Red seeds, Sesame seeds and Ajwan seeds.

    Science.gov (United States)

    Mabood, Fazal; Gilani, Syed Abdullah; Hussain, Javid; Alshidani, Sulaiman; Alghawi, Said; Albroumi, Mohammed; Alameri, Saif; Jabeen, Farah; Hussain, Zahid; Al-Harrasi, Ahmed; Al Abri, Zahra K M; Farooq, Saima; Naureen, Zakira; Hamaed, Ahmad; Rasul Jan, M; Shah, Jasmin

    2017-01-26

    New experimental designs for the extraction of polyphenols from different seeds including Basil seed, Red seed, Sesame seeds and Ajwan seeds were investigated. Four variables the concentration and volume of methanol and NaOH solutions as well as the temperature and time of extraction were varied to see their effect on total phenol extraction. The temperature was varied in the range from 25°C to 200°C while the time in the range from 30 to 200minutes. Response surface methodology was used to optimize the extraction parameters. The estimation of polyphenols was measured through phenols reduction UV-Vis spectroscopic method of phosphotungstic-phosphomolybdic acids (Folin-Ciocalteu's reagent). Calibration curve was made by using tannic acid as a polyphenols standard in the concentration range from 0.1 to 10ppm. The regression line obtained shows the value of correlation coefficient i.e. R=0.930 and Root mean square error of cross validation (RMSEC) value of 0.0654. The Basil seeds were found containing the highest amount of total phenols i.e. 785.76mg/100g. While the Sesame seeds having the least amount i.e. 33.08mg/100g. The Ajwan seeds and the Red seeds are containing the medium amounts i.e. 379mg/100g and 220.54mg/100g respectively.

  12. DIFFERENT APPROACHES TO CRYSTALLIZATION OF MEMBRANE PROTEINS

    Directory of Open Access Journals (Sweden)

    Prakash G. Doiphode

    2012-01-01

    Full Text Available Crystallography is more like an art than science. Crystallizing membrane proteins are a big challenge; membrane proteins are present in the cell membrane and serve as cell support. The most important feature of membrane protein is that it contains both hydrophobic and hydrophilic regions on its surface. They are generally much more difficult to study than soluble proteins. The problem becomes more difficult when trying to obtain crystals to determine the high resolution structures of membrane proteins. We want to utilize this opportunity to briefly examine various approaches for crystallization of membrane proteins. The important factors for determining the success of crystallization experiments for membrane proteins lies in the purification, preparation of membrane samples, the environment in which the crystals are grown and the technique used to grow the crystals. All the X-ray structures of membrane protein are grown from preparations of detergents by different methods developed to crystallize. In this review different techniques for the crystallization of membrane proteins are being described. The cubic phase method also known as in meso method is discussed along with other methods to understand about the crystallization of membrane proteins, its general applicability, salt, detergent and screening effects on crystallization. Low volumes as nano-liter of samples can be used for crystallization. The effects of different detergents on the crystallization of membrane protein, as well as the use of surfactants like polyoxyethylene. Approach based on the detergent complexation to prove the ability of cyclodextrins to remove detergent from ternary mixtures in order to get 2D crystals. Crystallization of membrane proteins using non-ionic surfactants as well as Lipidic sponge phase and with swollen lipidic mesophases is discussed to better understand the crystallization of membrane proteins.

  13. 银杏叶提取工艺正交试验研究%Orthogonal Experiment Study on Extraction Process of Ginkgo Leaves

    Institute of Scientific and Technical Information of China (English)

    姚建标; 王建方; 吴旭明; 金辉辉; 陈仲良

    2014-01-01

    Objective To determine the best extraction process of ginkgo leaves with the total transfer rate of total flavonol glycosides and terpene lactones as the index.Methods The effects of ethanol concentration, solid-liquid ratio and extraction time on extraction process were investigated by orthogonal design method, and the contents of total flavonol glycosides and terpene lactones were detected by HPLC to calculate transfer rate.Results The optimum extraction conditions were as follows:85% ethanol refluxing and extracting for three times;the first time extracting with five-fold amount of solvent (V/W) for 3 hours;the last two times with three-fold solvent (V/W) for 2 hours.Conclusion This extraction process has the advantages of simplicity of operator, reason, energy conservation, high efficiency, and is suitable for industrial production.%目的:以总黄酮醇苷、萜类内酯的综合转移率为指标,确定银杏叶最佳提取工艺。方法采用正交设计方法,系统考察乙醇浓度、料液比、提取时间3个因素对银杏叶提取工艺的影响,利用高效液相色谱法测定总黄酮醇苷、萜类内酯的含量,计算转移率。结果最佳提取工艺条件为:采用85%乙醇加热回流提取3次,第1次加5倍量(V/W)溶剂提取3 h,后2次分别加入3倍量(V/W)溶剂提取2 h。结论本工艺操作简单、合理、节能、高效,适用于工业化生产。

  14. Biological Macromolecule Crystallization Database

    Science.gov (United States)

    SRD 21 Biological Macromolecule Crystallization Database (Web, free access)   The Biological Macromolecule Crystallization Database and NASA Archive for Protein Crystal Growth Data (BMCD) contains the conditions reported for the crystallization of proteins and nucleic acids used in X-ray structure determinations and archives the results of microgravity macromolecule crystallization studies.

  15. Crystal-field effects in fluoride crystals for optical refrigeration

    Energy Technology Data Exchange (ETDEWEB)

    Hehlen, Markus P [Los Alamos National Laboratory

    2010-01-01

    The field of optical refrigeration of rare-earth-doped solids has recently seen an important breakthrough. The cooling of a YLiF{sub 4} (YLF) crystal doped with 5 mol% Yb3+ to 155 K by Seletskiy et al [NPhot] has surpassed the lowest temperatures ({approx}170 K for {approx}100 mW cooling capacity) that are practical with commercial multi-stage thermoelectric coolers (TEC) [Glaister]. This record performance has advanced laser cooling into an application relevant regime and has put first practical optical cryocoolers within reach. The result is also relevant from a material perspective since for the first time, an Yb3+-doped crystal has outperformed an Yb3+-doped glass. The record temperature of 208 K was held by the Yb3+-doped fluorozirconate glass ZBLAN. Advanced purification and glass fabrication methods currently under development are expected to also advance ZBLAN:Yb3+ to sub-TEC temperatures. However, recent achievements with YLF:Yb3+ illustrate that crystalline materials may have two potentially game-changing advantajes over glassy materials. First, the crystalline environment reduces the inhomogeneous broadening of the Yb3+ electronic transitions as compared to a glassy matrix. The respective sharpening of the crystal-field transitions increases the peak absorption cross section at the laser excitation wavelength and allows for more efficient pumping of the Yb3+ ions, particularly at low temperatures. Second, many detrimental impurities present in the starting materials tend to be excluded from the crystal during its slow growth process, in contrast to a glass where all impurities present in the starting materials are included in the glass when it is formed by temperature quenching a melt. The ultra high purity required for laser cooling materials [PRB] therefore may be easier to realize in crystals than in glasses. Laser cooling occurs by laser excitation of a rare-earth ion followed by anti-Stokes luminescence. Each such laser-cooling cycle extracts

  16. Demonstrations with a Liquid Crystal Shutter

    Science.gov (United States)

    Kraftmakher, Yaakov

    2012-01-01

    The experiments presented show the response of a liquid crystal shutter to applied electric voltages and the delay of the operations. Both properties are important for liquid crystal displays of computers and television sets. Two characteristics of the shutter are determined: (i) the optical transmittance versus applied voltage of various…

  17. Liquid Crystals in Education--The Basics

    Science.gov (United States)

    Cepic, Mojca

    2012-01-01

    The introduction of teaching about liquid crystals is discussed from several points of view: the rationale why to teach them, the basics about liquid crystals or what the teacher should teach about them, the fundamental pre-knowledge of students required, the set of experiments accompanying the teaching and the brief report on the already…

  18. Design of experiment approach for the optimization of polybrominated diphenyl ethers determination in fine airborne particulate matter by microwave-assisted extraction and gas chromatography coupled to tandem mass spectrometry.

    Science.gov (United States)

    Beser, Maria Isabel; Beltrán, Joaquim; Yusà, Vicent

    2014-01-03

    A sensitive and selective procedure for the determination of 12 polybrominated diphenyl ethers (BDE-28, BDE-49, BDE-47, BDE-66, BDE-100, BDE-119, BDE-99, BDE-155, BDE-154, BDE-153, BDE-139 and BDE-183) in airbone particulate matter (PM2.5) at trace level has been developed. The proposed method includes extraction PM2.5-bound PBDEs by microwave-assisted extraction (MAE) followed by gel permeation chromatography (GPC) clean-up and determination by GC-MS/MS using a programmed temperature vaporizer (PTV) in large volume injection (LVI) mode to introduce the sample to the chromatographic system. A design of experiment (DoE) approach was used for the optimization of large volume injection and microwave-assisted extraction parameters to improve these techniques efficiency. Other conditions of the method were studied: GC-MS/MS parameters, extraction solvent and matrix effect. The limit of quantification ranged from 0.063pgm(-3) to 0.210pgm(-3) when air volumes of 723m(3) were collected. Recoveries ranged from 80% to 106%. The method was successfully applied to eight real samples collected from a residential area of the monitoring network of the Region of Valencia Government (Spain) during April-August 2012. BDE-47 and BDE-99 were quantified in six and five samples respectively. The concentrations were ranged from 0.063 to 0.112pgm(-3) for BDE-47, and from 0.107 to 0.212pgm(-3) for BDE-99.

  19. Optimization of spraying dry process of licorice extract by orthogonal experiment%正交试验法优选甘草浸膏的喷雾干燥工艺

    Institute of Scientific and Technical Information of China (English)

    吕子明; 于向红; 刘晓燕; 关宏峰; 王超; 梁俊清

    2013-01-01

    Objective To investigate the spraying dry process of Licorice extract. Methods The effects of inlet temperature,outlet temperature and specific gravity of the extract on the spraying dry process of Licorice extract were inspected by L9(34) orthogonal experiment with powder amount,Iiquiritin and Glycyrrhizic acid contents as well as moisture content as the indexes. Results The optimal spraying dry process was: inlet temperature as 180℃,outlet temperature as 90℃ and specific gravity as 1.15. Conclusion The optimal spraying dry process is rational,stable and provided experiment base for industrial production.%目的 研究甘草浸膏的喷雾干燥工艺.方法 采用L9(34)正交设计法,以喷雾粉出粉量、甘草苷和甘草酸的含量以及水分为检测指标,考察进风口温度、出风口温度、浸膏比重对甘草浸膏喷雾干燥的影响.结果 优选喷雾干燥工艺为:进风口温度150℃、出风口温度90℃、浸膏比重1.15.结论 该工艺合理、稳定,为工业化生产提供了实验依据.

  20. Ribbon crystals.

    Directory of Open Access Journals (Sweden)

    Jakob Bohr

    Full Text Available A repetitive crystal-like pattern is spontaneously formed upon the twisting of straight ribbons. The pattern is akin to a tessellation with isosceles triangles, and it can easily be demonstrated with ribbons cut from an overhead transparency. We give a general description of developable ribbons using a ruled procedure where ribbons are uniquely described by two generating functions. This construction defines a differentiable frame, the ribbon frame, which does not have singular points, whereby we avoid the shortcomings of the Frenet-Serret frame. The observed spontaneous pattern is modeled using planar triangles and cylindrical arcs, and the ribbon structure is shown to arise from a maximization of the end-to-end length of the ribbon, i.e. from an optimal use of ribbon length. The phenomenon is discussed in the perspectives of incompatible intrinsic geometries and of the emergence of long-range order.

  1. Crystallization process

    Science.gov (United States)

    Adler, Robert J.; Brown, William R.; Auyang, Lun; Liu, Yin-Chang; Cook, W. Jeffrey

    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.

  2. Extraction of Ginsenoside with Orthogonal Experiment and Preparation of Supple Ginseng Shampoo%人参活性物质的提取及人参柔顺洗发水的研制

    Institute of Scientific and Technical Information of China (English)

    万玉华; 蒋日琼; 刘丹丹; 徐静; 张榕文; 吴志强

    2011-01-01

    为优化人参活性物质Rg1、Re、Rb1的提取工艺,研制人参柔顺洗发水,采用L9(33)正交试验表设计人参皂苷的提取工艺,选用药粉目数、溶剂倍量、提取时间为考察因素,以人参皂苷Rg1、Re、Rb1为测定指标筛选最佳工艺参数;结合头发梳理测试,研究人参提取液在洗发水中的最佳添加量.结果发现:人参提取液最佳制备工艺为24目粉末,7倍量水,提取1 h;人参提取液在洗发水中的最佳添加量为15%.可以得出:人参活性物质--皂苷类成分的提取工艺方便且结果可靠,洗发水研制路线全面、合理,可为产业化生产提供实验数据.%To optimize the technology for extraction of ginsenoside Rg1 , Re and Rbi , prepare the supple ginseng shampoo, the ginsenoside Rg, , Re and Rb, were used as the evaluation indexes, L9(33) orthogonal experiment was designed to study the effect of concentration of mesh powder , solvent quantity and extraction time on extraction rate of alkaloids; the best concentration of ginseng extract used in shampoo was also studied through hair combing test. The best extracting conditions were as follows s 24 mesh ginseng powder, adding 7-fold amount of water and extracting for an hour; The best concentration for ginseng extract used in shampoo was 15%. This technology for extracting ginsenoside is convenient and feasible, the preparation of shampoo is comprehensive and reasonable, it produces beneficial data for industrial production.

  3. On the observation of unusual high concentration of small chain-like aggregate ice crystals and large ice water contents near the top of a deep convective cloud during the CIRCLE-2 experiment

    Directory of Open Access Journals (Sweden)

    J.-F. Gayet

    2011-08-01

    Full Text Available During the CIRCLE-2 experiment carried out over Western Europe in May 2007, combined in situ and remote sensing observations allowed to describe microphysical and optical properties near-top of an overshooting convective cloud (11 080 m/−58 °C. The airborne measurements were performed with the DLR Falcon aircraft specially equipped with a unique set of instruments for the extensive in situ cloud measurements of microphysical and optical properties (Polar Nephelometer, FSSP-300, Cloud Particle Imager and PMS 2D-C and nadir looking remote sensing observations (DLR WALES Lidar. Quasi-simultaneous space observations from MSG/SEVIRI, CALIPSO/CALIOP-WFC-IIR and CloudSat/CPR combined with airborne RASTA radar reflectivity from the French Falcon aircraft flying above the DLR Falcon depict very well convective cells which overshoot by up to 600 m the tropopause level. Unusual high values of the concentration of small ice particles, extinction, ice water content (up to 70 cm−3, 30 km−1 and 0.5 g m−3, respectively are experienced. This very dense cloud causes a strong attenuation of the WALES and CALIOP lidar returns. The mean effective diameter is of 43 μm and the maximum particle size is about 300 μm. The SEVIRI retrieved parameters confirm the occurrence of small ice crystals at the top of the convective cell. Smooth and featureless phase functions with asymmetry factors of 0.776 indicate fairly uniform optical properties. Due to small ice crystals the power-law relationship between ice water content (IWC and radar reflectivity appears to be very different from those usually found in cirrus and anvil clouds. For a given equivalent reflectivity factor, IWCs are significantly larger for the overshooting cell than for the cirrus. Assuming the same prevalent microphysical properties over the depth of the overshooting cell, RASTA reflectivity profiles scaled into ice water content show that retrieved IWC up to 1 g

  4. On the observation of unusual high concentration of small chain-like aggregate ice crystals and large ice water contents near the top of a deep convective cloud during the CIRCLE-2 experiment

    Directory of Open Access Journals (Sweden)

    J.-F. Gayet

    2012-01-01

    Full Text Available During the CIRCLE-2 experiment carried out over Western Europe in May 2007, combined in situ and remote sensing observations allowed to describe microphysical and optical properties near-top of an overshooting convective cloud (11 080 m/−58 °C. The airborne measurements were performed with the DLR Falcon aircraft specially equipped with a unique set of instruments for the extensive in situ cloud measurements of microphysical and optical properties (Polar Nephelometer, FSSP-300, Cloud Particle Imager and PMS 2-D-C and nadir looking remote sensing observations (DLR WALES Lidar. Quasi-simultaneous space observations from MSG/SEVIRI, CALIPSO/CALIOP-WFC-IIR and CloudSat/CPR combined with airborne RASTA radar reflectivity from the French Falcon aircraft flying above the DLR Falcon depict very well convective cells which overshoot by up to 600 m the tropopause level. Unusual high values of the concentration of small ice particles, extinction, ice water content (up to 70 cm−3, 30 km−1 and 0.5 g m−3, respectively are experienced. The mean effective diameter and the maximum particle size are 43 μm and about 300 μm, respectively. This very dense cloud causes a strong attenuation of the WALES and CALIOP lidar returns. The SEVIRI retrieved parameters confirm the occurrence of small ice crystals at the top of the convective cell. Smooth and featureless phase functions with asymmetry factors of 0.776 indicate fairly uniform optical properties. Due to small ice crystals the power-law relationship between ice water content (IWC and radar reflectivity appears to be very different from those usually found in cirrus and anvil clouds. For a given equivalent reflectivity factor, IWCs are significantly larger for the overshooting cell than for the cirrus. Assuming the same prevalent microphysical properties over the depth of the overshooting cell, RASTA reflectivity profiles scaled into ice water content show that retrieved

  5. Contribution to the study of the readout of the electromagnetic calorimeter crystals in the CMS experiment at LHC; Contribution a l`etude de la lecture des cristaux du calorimetre electromagnetique de l`experience CMS au LHC

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Franck [Universite Claude Bernard Lyon-1, 69 - Lyon (France)

    1998-07-03

    The search for neutral Higgs boson through its decay into two photons provides a very promising signal for a mass between 90 and 150 GeV. It requires an electromagnetic calorimeter of very high resolution. The CMS (Compact Muon Solenoid) electromagnetic calorimeter must be made up of more than 80,000 lead tungstate crystals. In the central part (the barrel), the scintillation light readout is performed by means of avalanche photodiodes, a silicon photo-sensor with internal gain which is a relative novelty in high energy physics. Concerning the readout electronics, the energy available in the centre-of-mass (14 TeV) as well as the collision frequency (40 MHz) of LHC impose constraints with respect to the signal treatment up to the acquisition. The retained solution consists in pairing two avalanche photodiodes, the parameters of which (gain, temperature dependence, dark current, etc) must be controlled, and coupling them to a low noise preamplifier of high dynamical range (5 MeV - 2 TeV) followed by a four-slopes linear compressor and a analog-digital sampling converter of 12 bits, 40 MHz. The thesis presents the prototypes of different electromagnetic calorimeters tested in the high energy beam. An energy resolution of 0.6% at 100 GeV was obtained with a conventional readout circuitry, while the integrated associated circuits were radiation resistant 73 refs., 100 figs., 19 tabs.

  6. DANCE (Detector for Advanced Neutron Capture Experiments) is a 4π array of BaF2 crystals installed at LANSCE, Lujan Center. Neutron capture measurements on ^157Gd and ^89Y nuclei were conducted using this facility.

    Science.gov (United States)

    Chyzh, A.; Mitchell, G.; Vieira, D.; Bredeweg, T.; Ullmann, J.; Jandel, M.; Couture, A.; Keksis, A.; Rundberg, R.; Wilhelmy, J.; O'Donnell, J.; Baramsai, B.; Haight, R.; Wouters, J.; Krticka, M.; Parker, W.; Becker, J.; Agvaanlusan, U.

    2009-10-01

    DANCE (Detector for Advanced Neutron Capture Experiments) is a 4π array of BaF2 crystals installed at LANSCE, Lujan Center. Neutron capture measurements on ^157Gd and ^89Y nuclei were conducted using this facility. The absolute cross sections of the ^89Y(n,γ) reaction was measured for the first time ever in the neutron energy range of 10 eV -- 10 keV and improvements were made in the 10 -- 300 keV range. The error bars were significantly reduced and number of cross section points was increased since the past ^89Y(n,γ) experiments. The ^157Gd(n,γ) cross section was determined at En = 20 eV -- 300 keV by normalizing the experimental DANCE data to a well known resonance taken from the ENDF/B-VII library. Computer simulations of the ^157Gd(n,γ) cascades and DANCE pulse height function were made using DICEBOX and GEANT4 codes and simulated Esum and Eγ spectra are compared to the experimental DANCE data. Values of spin and photon strength function (PSF) of the ^157Gd(n,γ) resonances are provided in the range of En = 2 -- 300 eV using spin dependence upon a γ-ray multiplicity.

  7. Application of Membrane Crystallization for Minerals’ Recovery from Produced Water

    Directory of Open Access Journals (Sweden)

    Aamer Ali

    2015-11-01

    Full Text Available Produced water represents the largest wastewater stream from oil and gas production. Generally, its high salinity level restricts the treatment options. Membrane crystallization (MCr is an emerging membrane process with the capability to extract simultaneously fresh water and valuable components from various streams. In the current study, the potential of MCr for produced water treatment and salt recovery was demonstrated. The experiments were carried out in lab scale and semi-pilot scale. The effect of thermal and hydrodynamic conditions on process performance and crystal characteristics were explored. Energy dispersive X-ray (EDX and X-ray diffraction (XRD analyses confirmed that the recovered crystals are sodium chloride with very high purity (>99.9%, also indicated by the cubic structure observed by microscopy and SEM (scanning electron microscopy analysis. It was demonstrated experimentally that at recovery factor of 37%, 16.4 kg NaCl per cubic meter of produced water can be recovered. Anti-scaling surface morphological features of membranes were also identified. In general, the study provides a new perspective of isolation of valuable constituents from produced water that, otherwise, is considered as a nuisance.

  8. The Growth of Large Single Crystals.

    Science.gov (United States)

    Baer, Carl D.

    1990-01-01

    Presented is an experiment which demonstrates principles of experimental design, solubility, and crystal growth and structure. Materials, procedures and results are discussed. Suggestions for adapting this activity to the high school laboratory are provided. (CW)

  9. Ab-initio calculations of Judd–Ofelt intensity parameters for transitions between crystal-field levels

    Energy Technology Data Exchange (ETDEWEB)

    Wen, Jun, E-mail: wenjunkd@mail.ustc.edu.cn [School of Physics and Electric Engineering, Anqing Normal University, Anqing 246011 (China); Department of Physics, University of Science and Technology of China, Hefei 230026 (China); Reid, Michael F. [Department of Physics and Astronomy and MacDiarmid Institute for Advanced Materials and Nanotechnology, University of Canterbury, PB4800 Christchurch (New Zealand); Ning, Lixin [Department of Physics, Anhui Normal University, Wuhu 241000 (China); Zhang, Jie [School of Physics and Electric Engineering, Anqing Normal University, Anqing 246011 (China); Zhang, Yongfan [Department of Chemistry, Fuzhou University, Fuzhou, Fujian 350002 (China); Duan, Chang-Kui; Yin, Min [Department of Physics, University of Science and Technology of China, Hefei 230026 (China)

    2014-08-01

    Wavefunction-based ab-initio calculations of the electric-dipole moments of 4f{sup N}–4f{sup N} transitions of lanthanide ions are performed to extract the A{sub tp}{sup λ} intensity parameters. The extraction method is an extension of our earlier calculations of crystal-field (CF) parameters for lanthanide ions in crystals. The CASSCF/RASSI-SO (Complete-Active-Space Self-Consistent-Field/Restricted-Active-Space State-Interaction Spin-Orbit) calculations have been carried out on the chosen model system of CaF{sub 2}: Ce{sup 3+} with an interstitial fluoride ion (F{sub i}{sup −}) on z-axis (Ce{sup 3+} ion occupying the C{sub 4v} symmetry site). In consideration of the site symmetry and the coordination situation of Ce{sup 3+} ion at C{sub 4v} site in CaF{sub 2} as well as the superposition model (SM), the calculated intensity parameters for Ce{sup 3+} ion can be classified into three categories, and detailed discussions are then given. - Highlights: • Extraction of transition intensity parameters from ab-initio calculations. • CASSCF/RASSI-SO calculations are performed for Ce{sup 3+}-doped CaF{sub 2} crystal (C{sub 4v} case). • Extracted parameters are analyzed and compared with experiment and other calculation.

  10. Study of Unexplained Hard Photon Production by Electrons Channelled in a Crystal

    CERN Multimedia

    2002-01-01

    Our preceding experiment (NA33) designed to study the pair creation process in the interaction of high energy @g with a crystal in alignment conditions had revealed the existence of an unexpected peak in the radiation of 150~GeV~e|-~beam for E&s'@g./E^e^- @= 0.85 incident along the $$ axis of a 185~@mm. Ge~crystal and the photon multiplicity for the peak events has been measured to be M @= 5.7.\\\\ \\\\ In NA42, in a 76~@mm crystal of the same crystallographic quality, the peak nearly disappears, and the photon multiplicity at x = 0.85 is only M~@=~2.0. \\\\ \\\\ The thickness dependence of the effect shows that the extrapolated multiplicity in the peak in a very thin crystal tends to unity. The high energy radition peak emitted by axially channelled electrons in a thick crystal is then interpreted by the radiation cooling mechanism. \\\\ \\\\ The extrapolation to zero thickness of these results will allow us to extract from the data the single @g radiation spectrum. The comparison of this spectrum with the constant ...

  11. Stirred batch crystallization of a therapeutic antibody fragment.

    Science.gov (United States)

    Hebel, Dirk; Huber, Sabine; Stanislawski, Bernd; Hekmat, Dariusch

    2013-07-20

    Technical-scale crystallization of therapeutic proteins may not only allow for a significant cost-reduction in downstream processing, but also enable new applications, e.g., the use of crystal suspensions for subcutaneous drug delivery. In this work, the crystallization of the antigen-binding fragment FabC225 was studied. First, vapor diffusion crystallization conditions from the literature were transferred to 10μL-scale microbatch experiments. A phase diagram was developed in order to identify the crystallization window. The conditions obtained from the microbatch experiments were subsequently transferred to parallelized 5mL-scale stirred-tank crystallizers. This scalable and reproducible agitated crystallization system allowed for an optimization of the crystallization process based on quantitative measurements. The optimized crystallization process resulted in an excellent yield of 99% in less than 2h by increasing the concentration of the crystallization agent ammonium sulfate during the process. The successful scalability of the Fab fragment crystallization process to 100mL-scale crystallizers based on geometric similarity was demonstrated. A favorable crystal size distribution was obtained. Furthermore, a wash step was introduced in order to remove unfavorable low-molecular substances from the crystals.

  12. Electromembrane extraction

    DEFF Research Database (Denmark)

    Huang, Chuixiu; Chen, Zhiliang; Gjelstad, Astrid

    2017-01-01

    Electromembrane extraction (EME) was inspired by solid-phase microextraction and developed from hollow fiber liquid-phase microextraction in 2006 by applying an electric field over the supported liquid membrane (SLM). EME provides rapid extraction, efficient sample clean-up and selectivity based...

  13. Fractional decay of quantum dots in real photonic crystals

    DEFF Research Database (Denmark)

    Kristensen, Philip Trøst; Koenderink, A. Femius; Lodahl, Peter;

    2008-01-01

    We show that fractional decay may be observable in experiments using quantum dots and photonic crystals with parameters that are currently achievable. We focus on the case of inverse opal photonic crystals and locate the position in the crystal where the effect is most pronounced. Furthermore, we...

  14. Batch cooling crystallization and pressure filtration of sulphathiazole

    DEFF Research Database (Denmark)

    Häkkinen, Antti; Pöllänen, Kati; Karjalainen, Milja

    2005-01-01

    crystal suspensions obtained through an unseeded batch-cooling-crystallization process was studied. Sulphathiazole, which is an antibiotic agent with multiple polymorphic forms, was produced by performing laboratory-scale cooling crystallization experiments from five different mixtures of water and propan...

  15. Experiences with archived raw diffraction images data: capturing cisplatin after chemical conversion of carboplatin in high salt conditions for a protein crystal.

    Science.gov (United States)

    Tanley, Simon W M; Diederichs, Kay; Kroon-Batenburg, Loes M J; Schreurs, Antoine M M; Helliwell, John R

    2013-11-01

    The archiving of raw diffraction images data is the focus of an IUCr Diffraction Data Deposition Working Group (see http://forums.iucr.org/). Experience in archiving and sharing of raw diffraction images data in collaboration between Manchester and Utrecht Universities, studying the binding of the important anti-cancer agents, cisplatin and carboplatin to histidine in a protein, has recently been published. Subsequently, these studies have been expanded due to further analyses of each data set of raw diffraction images using the diffraction data processing program XDS. The raw diffraction images, measured at Manchester University, are available for download at Utrecht University and now also mirrored at the Tardis Raw Diffraction Data Archive in Australia. Thus a direct comparison of processed diffraction and derived protein model data from XDS with the published results has been made. The issue of conversion of carboplatin to cisplatin under a high chloride salt concentration has been taken up and a detailed crystallographic assessment is provided. Overall, these new structural chemistry research results are presented followed by a short summary of developing raw data archiving policy and practicalities as well as documenting the challenge of making appropriate and detailed recording of the metadata for crystallography.

  16. Vacuum extraction

    DEFF Research Database (Denmark)

    Maagaard, Mathilde; Oestergaard, Jeanett; Johansen, Marianne

    2012-01-01

    Objectives. To develop and validate an Objective Structured Assessment of Technical Skills (OSATS) scale for vacuum extraction. Design. Two part study design: Primarily, development of a procedure-specific checklist for vacuum extraction. Hereafter, validationof the developed OSATS scale for vacuum...... extraction in a prospective observational study. Setting. Rigshospitalet, University Hospital of Copenhagen. Population. For development an obstetric expert from each labor ward in Denmark (28 departments) were invited to participate. For validation nine first-year residents and ten chief physicians...... with daily work in the obstetric field were tested. Methods. The Delphi method was used for development of the scale. In a simulated vacuum extraction scenario first-year residents and obstetric chief physicians were rated using the developed OSATS scale for vacuum extraction to test construct validity...

  17. Vacuum extraction

    DEFF Research Database (Denmark)

    Maagaard, Mathilde; Oestergaard, Jeanett; Johansen, Marianne

    2012-01-01

    Objectives. To develop and validate an Objective Structured Assessment of Technical Skills (OSATS) scale for vacuum extraction. Design. Two part study design: Primarily, development of a procedure-specific checklist for vacuum extraction. Hereafter, validationof the developed OSATS scale for vacuum...... extraction in a prospective observational study. Setting. Rigshospitalet, University Hospital of Copenhagen. Population. For development an obstetric expert from each labor ward in Denmark (28 departments) were invited to participate. For validation nine first-year residents and ten chief physicians...... with daily work in the obstetric field were tested. Methods. The Delphi method was used for development of the scale. In a simulated vacuum extraction scenario first-year residents and obstetric chief physicians were rated using the developed OSATS scale for vacuum extraction to test construct validity...

  18. Processo químico industrial de extração de óleo vegetal: um experimento de química geral Chemical industrial process of vegetable oil extraction: an experiment for teaching general chemistry

    Directory of Open Access Journals (Sweden)

    José Francisco Vianna

    1999-09-01

    Full Text Available In this study we describe an experimental procedure based on a chemical industrial process of soya-bean oil extraction applied in general chemistry for undergraduate students. The experiment was planned according to the Science, Technology and Society (STS approach to teach basic chemical concepts and provide grounding in the management of environmental care. The use of real life chemistry problems seems to salient the relevance of chemistry to our students and enhances their motivation to learn both the practical and theoretical components of the discipline.

  19. Neutron Transmission through Sapphire Crystals

    DEFF Research Database (Denmark)

    Sapphire crystals are excellent filters of fast neutrons, while at the same time exhibit moderate to very little absorption at smaller energies. We have performed an extensive series of measurements in order to quantify the above effect. Alongside our experiments, we have performed a series...... of simulations, in order to reproduce the transmission of cold neutrons through sapphire crystals. Those simulations were part of the effort of validating and improving the newly developed interface between the Monte-Carlo neutron transport code MCNP and the Monte Carlo ray-tracing code McStas....

  20. STUDY ON LIQUID-LIQUID EXTRACTION OF RESVERATROL FROM GIANT KNOTWEED AND ITS PROTECTIVE EFFECT ON MYOCARDIUM INJURY

    Institute of Scientific and Technical Information of China (English)

    唐玉海; 刘芸; 黄伟; 刘宏浪

    2002-01-01

    Objective An efficient extraction and separation method of resveratrol from a Chinese herb giant knotweed was developed and the protective effect of resveratrol on myocardium injury was investigated.Methods An orthogonal experiment was utilized to optimize the extraction conditions and the pure white crystal obtained utilizing the proposed method was used for the investigation of myocardium ischemic injury.Results Resveratrol was found to have many beneficial activities including the protective effect on the heart and the scavenging of free radical.Conclusion The protective effect of resveratrol on myocardium injury is related to the quenching of lipid peroxidation.