Science.gov

Sample records for mass eigenstate purity

  1. Measurement of the lifetime difference between Bs mass eigenstates.

    PubMed

    Acosta, D; Adelman, J; Affolder, T; Akimoto, T; Albrow, M G; Ambrose, D; Amerio, S; Amidei, D; Anastassov, A; Anikeev, K; Annovi, A; Antos, J; Aoki, M; Apollinari, G; Arisawa, T; Arguin, J-F; Artikov, A; Ashmanskas, W; Attal, A; Azfar, F; Azzi-Bacchetta, P; Bacchetta, N; Bachacou, H; Badgett, W; Barbaro-Galtieri, A; Barker, G J; Barnes, V E; Barnett, B A; Baroiant, S; Barone, M; Bauer, G; Bedeschi, F; Behari, S; Belforte, S; Bellettini, G; Bellinger, J; Ben-Haim, E; Benjamin, D; Beretvas, A; Bhatti, A; Binkley, M; Bisello, D; Bishai, M; Blair, R E; Blocker, C; Bloom, K; Blumenfeld, B; Bocci, A; Bodek, A; Bolla, G; Bolshov, A; Booth, P S L; Bortoletto, D; Boudreau, J; Bourov, S; Brau, B; Bromberg, C; Brubaker, E; Budagov, J; Budd, H S; Burkett, K; Busetto, G; Bussey, P; Byrum, K L; Cabrera, S; Campanelli, M; Campbell, M; Canepa, A; Casarsa, M; Carlsmith, D; Carron, S; Carosi, R; Cavalli-Sforza, M; Castro, A; Catastini, P; Cauz, D; Cerri, A; Cerrito, L; Chapman, J; Chen, C; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, I; Cho, K; Chokheli, D; Chou, J P; Chu, M L; Chuang, S; Chung, J Y; Chung, W-H; Chung, Y S; Ciobanu, C I; Ciocci, M A; Clark, A G; Clark, D; Coca, M; Connolly, A; Convery, M; Conway, J; Cooper, B; Cordelli, M; Cortiana, G; Cranshaw, J; Cuevas, J; Culbertson, R; Currat, C; Cyr, D; Dagenhart, D; Da Ronco, S; D'Auria, S; de Barbaro, P; De Cecco, S; De Lentdecker, G; Dell'Agnello, S; Dell'Orso, M; Demers, S; Demortier, L; Deninno, M; De Pedis, D; Derwent, P F; Dionisi, C; Dittmann, J R; Dörr, C; Doksus, P; Dominguez, A; Donati, S; Donega, M; Donini, J; D'Onofrio, M; Dorigo, T; Drollinger, V; Ebina, K; Eddy, N; Ehlers, J; Ely, R; Erbacher, R; Erdmann, M; Errede, D; Errede, S; Eusebi, R; Fang, H-C; Farrington, S; Fedorko, I; Fedorko, W T; Feild, R G; Feindt, M; Fernandez, J P; Ferretti, C; Field, R D; Flanagan, G; Flaugher, B; Flores-Castillo, L R; Foland, A; Forrester, S; Foster, G W; Franklin, M; Freeman, J C; Fujii, Y; Furic, I; Gajjar, A; Gallas, A; Galyardt, J; Gallinaro, M; Garcia-Sciveres, M; Garfinkel, A F; Gay, C; Gerberich, H; Gerdes, D W; Gerchtein, E; Giagu, S; Giannetti, P; Gibson, A; Gibson, K; Ginsburg, C; Giolo, K; Giordani, M; Giunta, M; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldschmidt, N; Goldstein, D; Goldstein, J; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González, O; Gorelov, I; Goshaw, A T; Gotra, Y; Goulianos, K; Gresele, A; Griffiths, M; Grosso-Pilcher, C; Grundler, U; Guenther, M; da Costa, J Guimaraes; Haber, C; Hahn, K; Hahn, S R; Halkiadakis, E; Hamilton, A; Han, B-Y; Handler, R; Happacher, F; Hara, K; Hare, M; Harr, R F; Harris, R M; Hartmann, F; Hatakeyama, K; Hauser, J; Hays, C; Hayward, H; Heider, E; Heinemann, B; Heinrich, J; Hennecke, M; Herndon, M; Hill, C; Hirschbuehl, D; Hocker, A; Hoffman, K D; Holloway, A; Hou, S; Houlden, M A; Huffman, B T; Huang, Y; Hughes, R E; Huston, J; Ikado, K; Incandela, J; Introzzi, G; Iori, M; Ishizawa, Y; Issever, C; Ivanov, A; Iwata, Y; Iyutin, B; James, E; Jang, D; Jarrell, J; Jeans, D; Jensen, H; Jeon, E J; Jones, M; Joo, K K; Jun, S Y; Junk, T; Kamon, T; Kang, J; Unel, M Karagoz; Karchin, P E; Kartal, S; Kato, Y; Kemp, Y; Kephart, R; Kerzel, U; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, J E; Kim, M J; Kim, M S; Kim, S B; Kim, S H; Kim, T H; Kim, Y K; King, B T; Kirby, M; Kirsch, L; Klimenko, S; Knuteson, B; Ko, B R; Kobayashi, H; Koehn, P; Kong, D J; Kondo, K; Konigsberg, J; Kordas, K; Korn, A; Korytov, A; Kotelnikov, K; Kotwal, A V; Kovalev, A; Kraus, J; Kravchenko, I; Kreymer, A; Kroll, J; Kruse, M; Krutelyov, V; Kuhlmann, S E; Kwang, S; Laasanen, A T; Lai, S; Lami, S; Lammel, S; Lancaster, J; Lancaster, M; Lander, R; Lannon, K; Lath, A; Latino, G; Lauhakangas, R; Lazzizzera, I; Le, Y; Lecci, C; LeCompte, T; Lee, J; Lee, J; Lee, S W; Lefèvre, R; Leonardo, N; Leone, S; Levy, S; Lewis, J D; Li, K; Lin, C; Lin, C S; Lindgren, M; Liss, T M; Lister, A; Litvintsev, D O; Liu, T; Liu, Y; Lockyer, N S; Loginov, A; Loreti, M; Loverre, P; Lu, R-S; Lucchesi, D; Lujan, P; Lukens, P; Lungu, G; Lyons, L; Lys, J; Lysak, R; MacQueen, D; Madrak, R; Maeshima, K; Maksimovic, P; Malferrari, L; Manca, G; Marginean, R; Marino, C; Martin, A; Martin, M; Martin, V; Martínez, M; Maruyama, T; Matsunaga, H; Mattson, M; Mazzanti, P; McFarland, K S; McGivern, D; McIntyre, P M; McNamara, P; NcNulty, R; Mehta, A; Menzemer, S; Menzione, A; Merkel, P; Mesropian, C; Messina, A; Miao, T; Miladinovic, N; Miller, L; Miller, R; Miller, J S; Miquel, R; Miscetti, S; Mitselmakher, G; Miyamoto, A; Miyazaki, Y; Moggi, N; Mohr, B; Moore, R; Morello, M; Fernandez, P A Movilla; Mukherjee, A; Mulhearn, M; Muller, T; Mumford, R; Munar, A; Murat, P; Nachtman, J; Nahn, S; Nakamura, I; Nakano, I; Napier, A; Napora, R; Naumov, D; Necula, V; Niell, F; Nielsen, J; Nelson, C; Nelson, T; Neu, C; Neubauer, M S; Newman-Holmes, C; Nigmanov, T; Nodulman, L; Norniella, O; Oesterberg, K; Ogawa, T; Oh, S H; Oh, Y D; Ohsugi, T; Okusawa, T; Oldeman, R; Orava, R; Orejudos, W; Pagliarone, C; Palencia, E; Paoletti, R; Papadimitriou, V; Pashapour, S; Patrick, J; Pauletta, G; Paulini, M; Pauly, T; Paus, C; Pellett, D; Penzo, A; Phillips, T J; Piacentino, G; Piedra, J; Pitts, K T; Plager, C; Pompos, A; Pondrom, L; Pope, G; Portell, X; Poukhov, O; Prakoshyn, F; Pratt, T; Pronko, A; Proudfoot, J; Ptohos, F; Punzi, G; Rademacker, J; Rahaman, M A; Rakitine, A; Rappoccio, S; Ratnikov, F; Ray, H; Reisert, B; Rekovic, V; Renton, P; Rescigno, M; Rimondi, F; Rinnert, K; Ristori, L; Robertson, W J; Robson, A; Rodrigo, T; Rolli, S; Rosenson, L; Roser, R; Rossin, R; Rott, C; Russ, J; Rusu, V; Ruiz, A; Ryan, D; Saarikko, H; Sabik, S; Safonov, A; St Denis, R; Sakumoto, W K; Salamanna, G; Saltzberg, D; Sanchez, C; Sansoni, A; Santi, L; Sarkar, S; Sato, K; Savard, P; Savoy-Navarro, A; Schlabach, P; Schmidt, E E; Schmidt, M P; Schmitt, M; Scodellaro, L; Scribano, A; Scuri, F; Sedov, A; Seidel, S; Seiya, Y; Semeria, F; Sexton-Kennedy, L; Sfiligoi, I; Shapiro, M D; Shears, T; Shepard, P F; Sherman, D; Shimojima, M; Shochet, M; Shon, Y; Shreyber, I; Sidoti, A; Siegrist, J; Siket, M; Sill, A; Sinervo, P; Sisakyan, A; Skiba, A; Slaughter, A J; Sliwa, K; Smirnov, D; Smith, J R; Snider, F D; Snihur, R; Soha, A; Somalwar, S V; Spalding, J; Spezziga, M; Spiegel, L; Spinella, F; Spiropulu, M; Squillacioti, P; Stadie, H; Stelzer, B; Stelzer-Chilton, O; Strologas, J; Stuart, D; Sukhanov, A; Sumorok, K; Sun, H; Suzuki, T; Taffard, A; Tafirout, R; Takach, S F; Takano, H; Takashima, R; Takeuchi, Y; Takikawa, K; Tanaka, M; Tanaka, R; Tanimoto, N; Tapprogge, S; Tecchio, M; Teng, P K; Terashi, K; Tesarek, R J; Tether, S; Thom, J; Thompson, A S; Thomson, E; Tipton, P; Tiwari, V; Tkaczyk, S; Toback, D; Tollefson, K; Tomura, T; Tonelli, D; Tönnesmann, M; Torre, S; Torretta, D; Tourneur, S; Trischuk, W; Tseng, J; Tsuchiya, R; Tsuno, S; Tsybychev, D; Turini, N; Turner, M; Ukegawa, F; Unverhau, T; Uozumi, S; Usynin, D; Vacavant, L; Vaiciulis, A; Varganov, A; Vataga, E; Vejcik, S; Velev, G; Veszpremi, V; Veramendi, G; Vickey, T; Vidal, R; Vila, I; Vilar, R; Vollrath, I; Volobouev, I; von der Mey, M; Wagner, P; Wagner, R G; Wagner, R L; Wagner, W; Wallny, R; Walter, T; Yamashita, T; Yamamoto, K; Wan, Z; Wang, M J; Wang, S M; Warburton, A; Ward, B; Waschke, S; Waters, D; Watts, T; Weber, M; Wester, W C; Whitehouse, B; Wicklund, A B; Wicklund, E; Williams, H H; Wilson, P; Winer, B L; Wittich, P; Wolbers, S; Wolfe, C; Wolter, M; Worcester, M; Worm, S; Wright, T; Wu, X; Würthwein, F; Wyatt, A; Yagil, A; Yang, C; Yang, U K; Yao, W; Yeh, G P; Yi, K; Yoh, J; Yoon, P; Yorita, K; Yoshida, T; Yu, I; Yu, S; Yu, Z; Yun, J C; Zanello, L; Zanetti, A; Zaw, I; Zetti, F; Zhou, J; Zsenei, A; Zucchelli, S

    2005-03-18

    We present measurements of the lifetimes and polarization amplitudes for B(0)(s)-->J/psiphi and B(0)(d)-->J/psiK(*0) decays. Lifetimes of the heavy and light mass eigenstates in the B(0)(s) system are separately measured for the first time by determining the relative contributions of amplitudes with definite CP as a function of the decay time. Using 203+/-15 B(0)(s) decays we obtain tau(L) = (1.05(+0.16)(-0.13) +/- 0.02) ps and tau(H) = (2.07(+0.58)(-0.46) +/- 0.03) ps. Expressed in terms of the difference DeltaGamma(s) and average Gamma(s), of the decay rates of the two eigenstates, the results are DeltaGamma(s)/Gamma(s) = (65(+25)(-33) +/- 1)% and DeltaGamma(s) = (0.47(+0.19)(-0.24) +/- 0.01) ps(-1).

  2. Mass eigenstates in bimetric theory with matter coupling

    SciTech Connect

    Schmidt-May, Angnis

    2015-01-01

    In this paper we study the ghost-free bimetric action extended by a recently proposed coupling to matter through a composite metric. The equations of motion for this theory are derived using a method which avoids varying the square-root matrix that appears in the matter coupling. We make an ansatz for which the metrics are proportional to each other and find that it can solve the equations provided that one parameter in the action is fixed. In this case, the proportional metrics as well as the effective metric that couples to matter solve Einstein's equations of general relativity including a matter source. Around these backgrounds we derive the quadratic action for perturbations and diagonalize it into generalized mass eigenstates. It turns out that matter only interacts with the massless spin-2 mode whose equation of motion has exactly the form of the linearized Einstein equations, while the field with Fierz-Pauli mass term is completely decoupled. Hence, bimetric theory, with one parameter fixed such that proportional solutions exist, is degenerate with general relativity up to linear order around these backgrounds.

  3. B physics: measurement of the lifetime difference between b_s mass eigenstates

    SciTech Connect

    Acosta, D.; The CDF Collaboration

    2005-04-28

    We present measurements of the lifetimes and polarization amplitudes for B{sub s}{sup 0} {yields} J/{psi}{phi} and B{sub d}{sup 0} {yields} J/{psi} K*{sup 0} decays. Lifetimes of the heavy (H) and light (L) mass eigenstates in the B{sub s}{sup 0} system are separately measured for the first time by determining the relative contributions of amplitudes with definite CP as a function of the decay time.

  4. Analysis of the mixing matrix in a model with coincident quark electroweak and mass eigenstates

    NASA Astrophysics Data System (ADS)

    Vidal, J.

    1988-08-01

    A new approach to relating quark masses and mixing angles was proposed by del Águila, Kane, and Quirós, in which the mass matrix for the weak eigenstates was assumed to be diagonal in the absence of mixing with heavier quarks. The purpose of this paper is to examine in detail the constraints of CP violation and B0-B¯ 0 mixing on the quark-mixing-angle matrix of the model and the range of mt for which the description could hold. For the case where CP violation and B0-B¯ 0 mixing arise from the quark mixing matrix the result is that, for at least some values of the parameters, mt can be as small as 85 GeV but not less. In addition, ||Vub||/||Vcb|| is required to be larger than 0.11, an important constraint on the model. Mixing and CP violation arising from flavor-changing currents present in the model are also examined.

  5. Xenon purity analysis for EXO-200 via mass spectrometry

    NASA Astrophysics Data System (ADS)

    Dobi, A.; Hall, C.; Slutsky, S.; Yen, Y.-R.; Aharmin, B.; Auger, M.; Barbeau, P. S.; Benitez-Medina, C.; Breidenbach, M.; Cleveland, B.; Conley, R.; Cook, J.; Cook, S.; Counts, I.; Craddock, W.; Daniels, T.; Davis, C. G.; Davis, J.; deVoe, R.; Dixit, M.; Dolinski, M. J.; Donato, K.; Fairbank, W.; Farine, J.; Fierlinger, P.; Franco, D.; Giroux, G.; Gornea, R.; Graham, K.; Gratta, G.; Green, C.; Hagemann, C.; Hall, K.; Hallman, D.; Hargrove, C.; Herrin, S.; Hughes, M.; Hodgson, J.; Juget, F.; Karelin, A.; Kaufman, L. J.; Kuchenkov, A.; Kumar, K.; Leonard, D. S.; Lutter, G.; Mackay, D.; MacLellan, R.; Marino, M.; Mong, B.; Montero Díez, M.; Morgan, P.; Müller, A. R.; Neilson, R.; Odian, A.; O'Sullivan, K.; Piepke, A.; Pocar, A.; Prescott, C. Y.; Pushkin, K.; Rivas, A.; Rollin, E.; Rowson, P. C.; Sabourov, A.; Sinclair, D.; Skarpaas, K.; Stekhanov, V.; Strickland, V.; Swift, M.; Twelker, K.; Vuilleumier, J.-L.; Vuilleumier, J.-M.; Weber, M.; Wichoski, U.; Wodin, J.; Wright, J. D.; Yang, L.

    2012-05-01

    We describe purity measurements of the natural and enriched xenon stockpiles used by the EXO-200 double beta decay experiment based on a mass spectrometry technique. The sensitivity of the spectrometer is enhanced by several orders of magnitude by the presence of a liquid nitrogen cold trap, and many impurity species of interest can be detected at the level of one part-per-billion or better. We have used the technique to screen the EXO-200 xenon before, during, and after its use in our detector, and these measurements have proven useful. This is the first application of the cold trap mass spectrometry technique to an operating physics experiment.

  6. Multiaxis laser eigenstates

    SciTech Connect

    Brunel, M.; Le Floch, A.; Bretenaker, F.

    1996-05-01

    We derive a theoretical model based on a generalized Jones matrix formalism to calculate the eigenstates of lasers with {ital N} propagation axes. Spatial separation of the beams is realized inside the cavity by a collection of double-refraction crystals. This method allows one to adapt the mode volume to the geometry of the active medium. {ital N}-forked eigenstates are isolated, and the possibility of scaling up the TEM{sub 00} output power of a monomode laser is shown. All these features are tested experimentally in two-, four-, and eight-axis lasers and show good agreement with the theoretical predictions. {copyright} {ital 1996 Optical Society of America.}

  7. Purity determination and uncertainty evaluation of folic acid by mass balance method.

    PubMed

    Gong, Hui; Huang, Ting; Yang, Yi; Wang, Haifeng

    2012-11-15

    Folic acid is one of the most important nutrient substances for human beings, especially for the pregnant women and infants. Therefore the purity determination of folic acid is particularly important. The mass balance method was employed to determine the purity of folic acid, by using the measures of high performance liquid chromatography (HPLC), Karl Fischer titration and other conventional approach. The moisture quantification of folic acid was a major problem since it is a thermally unstable substance and it is apt to contain crystal water. Therefore, a novel improved Karl Fischer method was established for accurate determination of the water content in folic acid, whose repeatability (RSD=2.9%) was significantly better than that of the original direct injection method (RSD=12%). The purity of folic acid certified reference material (CRM) determined by mass balance method was 90.9% with an expanded uncertainty of 0.35%, and the content of water (the major impurity) was 8.5%, with an expanded uncertainty of 0.32%. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. Chiral purity assay for Flindokalner using tandem mass spectrometry: method development, validation, and benchmarking.

    PubMed

    Young, Brandy L; Cooks, R G; Madden, Michelle C; Bair, Michael; Jia, Jingpin; Aubry, Anne-Françoise; Miller, Scott A

    2007-04-11

    The present work demonstrates the application and validation of a mass spectrometry method for quantitative chiral purity determination. The particular compound analyzed is Flindokalner, a Bristol-Myers Squibb drug candidate for post-stroke neuroprotection. Chiral quantification of Flindokalner was achieved using tandem mass spectrometry (MS/MS) and the kinetic method, a gas phase method used for thermochemical and chiral determinations. The MS/MS method was validated and benchmarked against two separate chromatographic techniques, chiral high performance liquid chromatography with ultra-violet detection (LC/UV) and achiral high performance liquid chromatography with circular dichroism detection (LC/CD). The chiral purity determination of Flindokalner using MS/MS proved to be rapid (3 min run time for each sample) and to have accuracy and precision comparable to the chiral LC/UV and achiral LC/CD methods. This method represents an alternative to commonly used chromatographic techniques as a means of chiral purity determination and is particularly useful in rapid screening experiments.

  9. Necessity of Eigenstate Thermalization

    NASA Astrophysics Data System (ADS)

    De Palma, Giacomo; Serafini, Alessio; Giovannetti, Vittorio; Cramer, Marcus

    2015-11-01

    Under the eigenstate thermalization hypothesis (ETH), quantum-quenched systems equilibrate towards canonical, thermal ensembles. While at first glance the ETH might seem a very strong hypothesis, we show that it is indeed not only sufficient but also necessary for thermalization. More specifically, we consider systems coupled to baths with well-defined macroscopic temperature and show that whenever all product states thermalize then the ETH must hold. Our result definitively settles the question of determining whether a quantum system has a thermal behavior, reducing it to checking whether its Hamiltonian satisfies the ETH.

  10. Alternatives to eigenstate thermalization.

    PubMed

    Rigol, Marcos; Srednicki, Mark

    2012-03-16

    An isolated quantum many-body system in an initial pure state will come to thermal equilibrium if it satisfies the eigenstate thermalization hypothesis (ETH). We consider alternatives to ETH that have been proposed. We first show that von Neumann's quantum ergodic theorem relies on an assumption that is essentially equivalent to ETH. We also investigate whether, following a sudden quench, special classes of pure states can lead to thermal behavior in systems that do not obey ETH, namely, integrable systems. We find examples of this, but only for initial states that obeyed ETH before the quench.

  11. Digitally synthesized high purity, high-voltage radio frequency drive electronics for mass spectrometry

    SciTech Connect

    Schaefer, R. T.; Mojarradi, M.; MacAskill, J. A.; Chutjian, A.; Darrach, M. R.; Madzunkov, S. M.; Shortt, B. J.

    2008-09-15

    Reported herein is development of a quadrupole mass spectrometer controller (MSC) with integrated radio frequency (rf) power supply and mass spectrometer drive electronics. Advances have been made in terms of the physical size and power consumption of the MSC, while simultaneously making improvements in frequency stability, total harmonic distortion, and spectral purity. The rf power supply portion of the MSC is based on a series-resonant LC tank, where the capacitive load is the mass spectrometer itself, and the inductor is a solenoid or toroid, with various core materials. The MSC drive electronics is based on a field programmable gate array (FPGA), with serial peripheral interface for analog-to-digital and digital-to-analog converter support, and RS232/RS422 communications interfaces. The MSC offers spectral quality comparable to, or exceeding, that of conventional rf power supplies used in commercially available mass spectrometers; and as well an inherent flexibility, via the FPGA implementation, for a variety of tasks that includes proportional-integral derivative closed-loop feedback and control of rf, rf amplitude, and mass spectrometer sensitivity. Also provided are dc offsets and resonant dipole excitation for mass selective accumulation in applications involving quadrupole ion traps; rf phase locking and phase shifting for external loading of a quadrupole ion trap; and multichannel scaling of acquired mass spectra. The functionality of the MSC is task specific, and is easily modified by simply loading FPGA registers or reprogramming FPGA firmware.

  12. Monitoring xenon purity in the LUX detector with a mass spectrometry system

    NASA Astrophysics Data System (ADS)

    Balajthy, Jon; LUX Experiment Collaboration

    2015-04-01

    The LUX dark matter search experiment is a 350 kg two-phase liquid/gas xenon time projection chamber located at the 4850 ft level of the Sanford Underground Research Facility in Lead, SD. To monitor for radioactive impurities such as krypton and impurities which limit charge yield such as oxygen, LUX uses a xenon sampling system consisting of a mass spectrometer and a liquid nitrogen cold trap. The cold trap separates the gaseous impurities from a small sample of xenon and allows them to pass to the mass spectrometer for analysis. We report here on results from the LUX xenon sampling program. We also report on methods to enhance the sensitivity of the cold trap technique in preparation for the next-generation LUX-ZEPLIN experiment which will have even more stringent purity requirements.

  13. Improvements in bis(cyclopentadienyl)magnesium purity as determined with gas chromatography-mass spectroscopy

    SciTech Connect

    BARTRAM,MICHAEL E.

    2000-03-08

    Bis(cyclopentadienyl)magnesium (MgCp2) is used commonly as a source for doping nitride materials with magnesium. Increased oxygen incorporation known to accompany the use of MgCp2 makes the purity of this precursor an important consideration in nitride CVD. Gas chromatography-mass spectroscopy (GCMS) methods have now been developed for the identification of volatile impurities in MgCp2. Diethylether, an oxygen containing organic compound (CH{sub 3}CH{sub 2}OCH{sub 2}CH{sub 3}), and additional organic impurities were found in the MgCp2 supplied by three manufacturers. Subsequent refinements in the synthetic processes by these companies have resulted in the availability of MgCp2 free of ether and other organic impurities as determined by GCMS.

  14. Determination of nitrogen monoxide in high purity nitrogen gas with an atmospheric pressure ionization mass spectrometer

    NASA Technical Reports Server (NTRS)

    Kato, K.

    1985-01-01

    An atmospheric pressure ionization mass spectrometric (API-MS) method was studied for the determination of residual NO in high purity N2 gas. The API-MS is very sensitive to NO, but the presence of O2 interferes with the NO measurement. Nitrogen gas in cylinders as sample gas was mixed with NO standard gas and/or O2 standard gas, and then introduced into the API-MS. The calibration curves of NO and O2 has linearity in the region of 0 - 2 ppm, but the slopes changed with every cylinder. The effect of O2 on NO+ peak was additive and proportional to O2 concentration in the range of 0 - 0.5 ppm. The increase in NO+ intensity due to O2 was (0.07 - 0.13)%/O2, 1 ppm. Determination of NO and O2 was carried out by the standard addition method to eliminate the influence of variation of slopes. The interference due to O2 was estimated from the product of the O2 concentration and the ratio of slope A to Slope B. Slope A is the change in the NO+ intensity with the O2 concentration. Slope B is the intensity with O2 concentration.

  15. Establishment of the purity values of carbohydrate certified reference materials using quantitative nuclear magnetic resonance and mass balance approach.

    PubMed

    Quan, Can

    2014-06-15

    This work described the assignment of purity values to six carbohydrate certified reference materials, including glucose, fructose, galactose, lactose, xylose and sucrose, according to the ISO Guides 34 and 35. The CRMs' purity values were assigned based on the weighted average of quantitative nuclear magnetic resonance method and mass balance approach with high resolution liquid chromatography - evaporative light scattering detection. All the six CRMs with following value amount fractions: glucose (GBW10062) at a certified purity P ± U (k=2) of (0.99 ± 0.005)%; fructose (GBW10063) at (0.99 ± 0.005)%; galactose (GBW10064) at (0.99 ± 0.007)%; lactose (GBW10065) at (0.99 ± 0.008)%; xylose (GBW10066) at (0.99 ± 0.007)% and sucrose (GBW10067) at (0.99 ± 0.008)%, respectively were certified. The homogeneity of the CRMs was determined by an in-house validated liquid chromatographic method. Potential degradation during storage was also investigated and a shelf-life based on this value was established. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Determination of rare earth impurities in high purity samarium oxide using inductively coupled plasma mass spectrometry after extraction chromatographic separation

    NASA Astrophysics Data System (ADS)

    Zhang, Xinquan; Liu, Jinglei; Yi, Yong; Liu, Yonglin; Li, Xiang; Su, Yaqin; Lin, Ping

    2007-01-01

    A method for the determination of trace of 14 rare earth elements (REEs) as impurities in high purity samarium oxide (Sm2O3) using inductively coupled plasma mass spectrometry (ICP-MS) was described. Analytes, such as La, Ce, Pr, Nd, Eu, Gd, Tb, Lu and Y were measured without Sm matrix separation because of no interference problems occurring that could affect the analysis of these elements. On the other hand, analytes, such as Dy, Ho, Er, Tm and Yb were carried out after Sm matrix being eliminated completely by means of 2-ethylhexyl hydrogen-ethylhexy phosphonate (EHEHP) extraction chromatographic separation. The inherent problem associated with matrix-induced suppression was effectively compensated with spiking In as internal standard element and the mass spectra isobaric interferences of atomic and molecular ions arose from Sm matrix had been overcome after the removal of Sm matrix. The limits of quantitations (LOQ) for 14 REEs impurities were from 0.01 to 0.07 [mu]g g-1 together with the recoveries of spiking sample of 14 REEs were found to be in the range of 85-110% and the proposed method precision was less than 5%. A synthetic standard Sm2O3 sample with well-known 14 REEs concentrations was prepared and analysed in order to prove the accuracy and precision of the proposed method together with another high purity Sm2O3 was also measured using ICP-MS. The methodology had been found to be suitable for the determination of trace of 14 REEs in 99.999-99.9999% high purity Sm2O3.

  17. Determination of trace elements in high purity alumina powder by helium enhanced direct current glow discharge mass spectrometry

    NASA Astrophysics Data System (ADS)

    Jung, Sehoon; Kim, Sunhye; Hinrichs, Joachim

    2016-08-01

    Trace impurities in high purity alumina powder were determined by fast flow direct current glow discharge mass spectrometry (GD-MS). The non-conductive samples were prepared with high purity graphite powder and used as a sample binder and as a secondary cathode. To improve the sensitivity of the GD-MS analysis, helium was introduced as an additional glow discharge gas to argon plasma. The quantification results of the GD-MS measurement were calculated by external calibration with matrix matched certified reference materials. The GD-MS results for the determination of Na, Mg, Si, Ca, Ti, V, Cr, Fe, Cu, Zn and Ga in the alumina samples agreed well with the certified values of a reference material and the results of chemical analysis using wet sample digestion with inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS). The GD-MS analysis is a rapid analysis technique to determine trace elements in non-conductive alumina to below mg·kg- 1 levels.

  18. [Determination of trace impurities in high purity titanium dioxide by high resolution inductively coupled plasma mass spectrometry].

    PubMed

    He, Xiao-Mei; Xie, Hua-Lin; Nie, Xi-Du; Tang, You-Gen

    2007-06-01

    An analytical method using high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) for the rapid simultaneous determination of twenty six elements (Be, Na, Mg, Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Mo, Cd, Sn, Sb, Ba, Ce, Nd, Sm, Pt, Pb and Bi) in high purity titanium dioxide was described. Samples were decomposed by (NH4)2SO4 and H2SO4. Most of the spectral interferences could be avoided by measuring in the high-resolution mode. The matrix effects due to the presence of excess sulfuric acid and Ti were evaluated. The optimum conditions for the determination were tested and discussed. The standard addition method was employed for quantitative analysis. The detection limits are 0.004-0.63 microg x g(-1), the recovery ratio is 87.6%-106.4%, and the RSD is less than 3.5%. The method is accurate, quick and convenient. It has been applied to the determination of trace impurities in high purity titanium dioxide with satisfactory results.

  19. Eigenstate Gibbs ensemble in integrable quantum systems

    NASA Astrophysics Data System (ADS)

    Nandy, Sourav; Sen, Arnab; Das, Arnab; Dhar, Abhishek

    2016-12-01

    The eigenstate thermalization hypothesis conjectures that for a thermodynamically large system in one of its energy eigenstates, the reduced density matrix describing any finite subsystem is determined solely by a set of relevant conserved quantities. In a chaotic quantum system, only the energy is expected to play that role and hence eigenstates appear locally thermal. Integrable systems, on the other hand, possess an extensive number of such conserved quantities and therefore the reduced density matrix requires specification of all the corresponding parameters (generalized Gibbs ensemble). However, here we show by unbiased statistical sampling of the individual eigenstates with a given finite energy density that the local description of an overwhelming majority of these states of even such an integrable system is actually Gibbs-like, i.e., requires only the energy density of the eigenstate. Rare eigenstates that cannot be represented by the Gibbs ensemble can also be sampled efficiently by our method and their local properties are then shown to be described by appropriately truncated generalized Gibbs ensembles. We further show that the presence of these rare eigenstates differentiates the model from the chaotic case and leads to the system being described by a generalized Gibbs ensemble at long time under a unitary dynamics following a sudden quench, even when the initial state is a typical (Gibbs-like) eigenstate of the prequench Hamiltonian.

  20. Determination of trace impurities in high purity gold by inductively coupled plasma mass spectrometry with prior matrix removal by electrodeposition

    NASA Astrophysics Data System (ADS)

    Sun, Y. C.; Hsieh, C. H.; Lin, T. S.; Wen, J. C.

    2000-09-01

    A novel method for the determination of 11 trace impurities (Be, Mg, Cr, Mn, Ni, Cu, Zn, Ag, Pd, Sn and Pb) in high purity gold with a combination of electrochemical deposition separation and inductively coupled plasma mass spectrometric measurement was investigated. In the present study, an efficient separation procedure was developed to remove the gold matrix by the electrodepositon method on the basis of the difference in reduction potential of gold and the other trace impurities. The effects of deposition potential, deposition time and composition of the electrolyte on the separation efficiency were studied. According to our experimental results, most impurities, except for silver, can remain in the electrolyte and the interference from gold can be completely removed through the application of electrodeposition at suitable potential. To achieve simultaneous separation of silver from the gold matrix, a unique complexation reaction between silver ions and ammonia ions was successfully employed to alter the reduction potential of silver ion. By way of a suitable adjustment of the deposition potential and the composition of electrolytes, the spike recoveries of 11 interesting impurities were found to be in the range of 85-105%. The limit of detection (based on the 3-σ criterion) of these elements was 10 -1-10 -2 μg g -1. The applicability of the proposed method has also been validated by the analysis of high purity gold reference materials (FAU9 and FAU11, Royal Canadian Mint). Comparing with the certified values, the recoveries of interesting elements were found to be in the range of 82-118% through the use of proposed method.

  1. Determination of rare earth elements in high purity rare earth oxides by liquid chromatography, thermionic mass spectrometry and combined liquid chromatography/thermionic mass spectrometry

    NASA Astrophysics Data System (ADS)

    Stijfhoorn, D. E.; Stray, H.; Hjelmseth, H.

    1993-03-01

    A high-performance liquid Chromatographie (HPLC) method for the determination of rare earth elements in rocks has been modified and used for the determination of rare earth elements (REE) in high purity rare earth oxides. The detection limit was 1-1.5 ng or 2-3 mg/kg when a solution corresponding to 0.5 mg of the rare earth oxide was injected. The REE determination was also carried out by adding a mixture of selected REE isotopes to the sample and analysing the collected HPLC-fractions by mass spectrometry (MS) using a thermionic source. Since the matrix element was not collected, interference from this element during the mass spectrometric analysis was avoided. Detection limits as low as 0.5 mg/kg could then be obtained. Detection limits as low as 0.05 mg/kg were possible by MS without HPLC-pre-separation, but this approach could only be used for those elements that were not affected by the matrix. Commercial samples of high purity Nd 2O 3, Gd 2O 3 and Dy 2O 3 were analysed in this study, and a comparison of results obtained by HPLC, combined HPLC/MS and direct MS are presented.

  2. The dynamics of spatially-resolved laser eigenstates

    SciTech Connect

    Bretenaker, F.; LeFloch, A. )

    1990-09-01

    The existence of partially spatially-resolved laser eigenstates is proven, using the polarization walkoff provided by an uniaxial birefringent crystal. The coupling between the ordinary and extraordinary eigenstates is shown to depend drastically on the relative positions of the different elements in the cavity, leading to different eigenstates dynamics. Rotation and inhibition vectorial bistability and vectorial simultaneity are successively isolated, the removal of the transversal degeneracy of the two eigenstates allowing a simple eigenstate selection.

  3. Eigenstate tracking in open quantum systems

    NASA Astrophysics Data System (ADS)

    Jing, Jun; Sarandy, Marcelo S.; Lidar, Daniel A.; Luo, Da-Wei; Wu, Lian-Ao

    2016-10-01

    Keeping a quantum system in a given instantaneous eigenstate is a control problem with numerous applications, e.g., in quantum information processing. The problem is even more challenging in the setting of open quantum systems, where environment-mediated transitions introduce additional decoherence channels. Adiabatic passage is a well-established solution but requires a sufficiently slow evolution time that is dictated by the adiabatic theorem. Here we develop a systematic projection theory formulation for the transitionless evolution of general open quantum systems described by time-local master equations. We derive a time-convolutionless dynamical equation for the target instantaneous eigenstate of a given time-dependent Hamiltonian. A transitionless dynamics then arises in terms of a competition between the average Hamiltonian gap and the decoherence rate, which implies optimal adiabaticity timescales. We show how eigenstate tracking can be accomplished via control pulses, without explicitly incorporating counter-diabatic driving, thus offering an alternative route to accelerate adiabaticity. We examine rectangular pulses, chaotic signals, and white noise, and find that, remarkably, the effectiveness of eigenstate tracking hardly depends on the details of the control functions. In all cases the control protocol keeps the system in the desired instantaneous eigenstate throughout the entire evolution, along an accelerated adiabatic path.

  4. Systematic Construction of Counterexamples to the Eigenstate Thermalization Hypothesis

    NASA Astrophysics Data System (ADS)

    Shiraishi, Naoto; Mori, Takashi

    2017-07-01

    We propose a general method to embed target states into the middle of the energy spectrum of a many-body Hamiltonian as its energy eigenstates. Employing this method, we construct a translationally invariant local Hamiltonian with no local conserved quantities, which does not satisfy the eigenstate thermalization hypothesis. The absence of eigenstate thermalization for target states is analytically proved and numerically demonstrated. In addition, numerical calculations of two concrete models also show that all the energy eigenstates except for the target states have the property of eigenstate thermalization, from which we argue that our models thermalize after a quench even though they do not satisfy the eigenstate thermalization hypothesis.

  5. Angular Momentum Eigenstates for Equivalent Electrons.

    ERIC Educational Resources Information Center

    Tuttle, E. R.; Calvert, J. B.

    1981-01-01

    Simple and efficient methods for adding angular momenta and for finding angular momentum eigenstates for systems of equivalent electrons are developed. Several different common representations are used in specific examples. The material is suitable for a graduate course in quantum mechanics. (SK)

  6. Angular Momentum Eigenstates for Equivalent Electrons.

    ERIC Educational Resources Information Center

    Tuttle, E. R.; Calvert, J. B.

    1981-01-01

    Simple and efficient methods for adding angular momenta and for finding angular momentum eigenstates for systems of equivalent electrons are developed. Several different common representations are used in specific examples. The material is suitable for a graduate course in quantum mechanics. (SK)

  7. Frustrated total internal reflection of laser eigenstates

    SciTech Connect

    Balcou, P.; Dutriaux, L.; Bretenaker, F.; Le Floch, A.

    1996-07-01

    The role of frustrated total internal reflection in the dynamics of laser eigenstates is investigated theoretically and experimentally. We first derive the Jones matrix of a frustrating element for a realistic Gaussian beam in a single-pass geometry. We point out the existence of three different angular regimes, namely, a pure frustration regime, an intermediate regime, and a quasi-Fabry{endash}Perot regime. We then explore in each case the nature and the competition between the laser polarization eigenstates. A novel spiraling behavior of the laser parameters is demonstrated when the frustrating gap is varied, along with puzzling polarization-flipping effects, that may modify strongly the conditions that optimize the laser-output power. Experimental results agree with a theoretical model. {copyright} {ital 1996 Optical Society of America.}

  8. PILOT STUDY: An international comparison of mass fraction purity assignment of theophylline: CCQM Pilot Study CCQM-P20.e (Theophylline)

    NASA Astrophysics Data System (ADS)

    Westwood, S.; Josephs, R.; Daireaux, A.; Wielgosz, R.; Davies, S.; Kang, M.; Ting, H.; Phillip, R.; Malz, F.; Shimizu, Y.; Frias, E.; Pérez, M.; Apps, P.; Fernandes-Whaley, M.; DeVos, B.; Wiangnon, K.; Ruangrittinon, N.; Wood, S.; Duewer, D.; Schantz, M.; Bedner, M.; Hancock, D.; Esker, J.

    2009-01-01

    Under the auspices of the Organic Analysis Working Group (OAWG) of the Comité Consultatif pour la Quantité de Matière (CCQM) a laboratory comparison, CCQM-P20.e, was coordinated by the Bureau International de Poids et Mesures (BIPM) in 2006/2007. Nine national measurement institutes, two expert laboratories and the BIPM participated in the comparison. Participants were required to assign the mass fraction of theophylline present as the main component in two separate study samples (CCQM-P20.e.1 and CCQM-P20.e.2). CCQM-P20.e.1 consisted of a high-purity theophylline material obtained from a commercial supplier. CCQM-P20.e.2 consisted of theophylline to which known amounts of the related structure compounds theobromine and caffeine were added in a homogenous, gravimetrically controlled fashion. For the CCQM-P20.e.2 sample it was possible to estimate gravimetric reference values both for the main component and for the two spiked impurities. In addition to assigning the mass fraction content of theophylline for both materials, participants were requested but not obliged to provide mass fraction estimates for the minor components they identified in each sample. The results reported by the study participants for the mass fraction content of theophylline in both materials showed good levels of agreement both with each other and with the gravimetric reference value assigned to the CCQM-P20.e.2 material. There was also satisfactory agreement overall, albeit at higher levels of uncertainty, in the quantification data reported for the minor components present in both samples. In the few cases where a significant deviation was observed from the consensus values reported by the comparison participants or gravimetric reference values where these where available, they appeared to arise from the use of non-optimal chromatographic separation conditions. The results demonstrate the feasibility for laboratories to assign mass fraction content with associated absolute expanded

  9. Whence the eigenstate-eigenvalue link?

    NASA Astrophysics Data System (ADS)

    Gilton, Marian J. R.

    2016-08-01

    David Wallace has recently argued that the eigenstate-eigenvalue (E-E) link has no place in serious discussions of quantum mechanics on the grounds that, as he claims, the E-E link is an invention of philosophers rather than the community of practicing physicists. This raises an historical question regarding the origin of the link. This paper aims to answer this question by tracing the historical development of the link through six key textbooks of quantum mechanics. In light of the historical evidence from these textbooks, it is argued that Wallace provides insufficient grounds for dismissing the E-E link from discussions of quantum mechanics.

  10. Energy eigenstates of magnetostatic waves and oscillations.

    PubMed

    Kamenetskii, E O

    2001-06-01

    Effect of excitation of magnetostatic oscillations in a ferrite resonator by the microwave magnetic field was a subject of many publications of more than the last 40 years. The most interesting multiresonance spectrum of absorption peaks one can observe experimentally is a case of disk-form small ferrite resonators. It is shown in this paper that such small ferrite resonators can be considered as "artificial molecular structures" with properties characterized by energy eigenstates of magnetostatic oscillations. A special interest in these properties may be found in the field of microwave artificial composite materials.

  11. Energy eigenstates of magnetostatic waves and oscillations

    SciTech Connect

    Kamenetskii, E. O.

    2001-06-01

    Effect of excitation of magnetostatic oscillations in a ferrite resonator by the microwave magnetic field was a subject of many publications of more than the last 40 years. The most interesting multiresonance spectrum of absorption peaks one can observe experimentally is a case of disk-form small ferrite resonators. It is shown in this paper that such small ferrite resonators can be considered as {open_quotes}artificial molecular structures{close_quotes} with properties characterized by energy eigenstates of magnetostatic oscillations. A special interest in these properties may be found in the field of microwave artificial composite materials.

  12. Thermality of eigenstates in conformal field theories

    NASA Astrophysics Data System (ADS)

    Basu, Pallab; Das, Diptarka; Datta, Shouvik; Pal, Sridip

    2017-08-01

    The eigenstate thermalization hypothesis (ETH) provides a way to understand how an isolated quantum mechanical system can be approximated by a thermal density matrix. We find a class of operators in (1+1)-dimensional conformal field theories, consisting of quasiprimaries of the identity module, which satisfy the hypothesis only at the leading order in large central charge. In the context of subsystem ETH, this plays a role in the deviation of the reduced density matrices, corresponding to a finite energy density eigenstate from its hypothesized thermal approximation. The universal deviation in terms of the square of the trace-square distance goes as the eighth power of the subsystem fraction and is suppressed by powers of inverse central charge (c ). Furthermore, the nonuniversal deviations from subsystem ETH are found to be proportional to the heavy-light-heavy structure constants which are typically exponentially suppressed in √{h /c }, where h is the conformal scaling dimension of the finite energy density state. We also examine the effects of the leading finite-size corrections.

  13. Differential measurement of the coupling constant between laser eigenstates

    SciTech Connect

    Brunel, M.; Vallet, M.; Le Floch, A.; Bretenaker, F.

    1997-04-01

    The possibility to measure the coupling constant C between eigenstates in a laser is demonstrated. Spatial separation of orthogonally polarized modes is shown to provide a simple differential tool to measure their coupling. The difference in the behaviors of linear and helicoidal eigenstates enlightens the influence of the nature of the eigenstates on their interaction in the active medium. The obtained experimental values are C=0.16 for linear and C=0.4 for helicoidal eigenstates in a longitudinally monomode Nd:YAG laser. The method is applicable to most kinds of laser. {copyright} {ital 1997 American Institute of Physics.}

  14. Final report on key comparison CCQM-K55.a (estradiol): An international comparison of mass fraction purity assignment of estradiol

    NASA Astrophysics Data System (ADS)

    Westwood, Steven; Josephs, Ralf; Daireaux, Adeline; Wielgosz, Robert; Davies, Stephen; Wang, Hongjie; Rodrigues, Jainana; Wollinger, Wagner; Windust, Anthony; Kang, Ma; Fuhai, Su; Philipp, Rosemarie; Kuhlich, Paul; Wong, Siu-kay; Shimizu, Yoshitaka; Pérez, Melina; Avila, Marco; Fernandes-Whaley, Maria; Prevoo, D.; de Vos, J.; Visser, R.; Archer, M.; LeGoff, Thierry; Wood, Steve; Bearden, Dan; Bedner, Mary; Boroujerdi, Arezue; Duewer, David; Hancock, Diane; Lang, Brian; Porter, Barbara; Schantz, Michele; Sieber, John; White, Edward; Wise, Stephen A.

    2012-01-01

    Under the auspices of the Organic Analysis Working Group (OAWG) of the Comité Consultatif pour la Quantité de Matière (CCQM) a key comparison, CCQM K55.a, was coordinated by the Bureau International des Poids et Mesures (BIPM) in 2009/2010. Eleven national measurement institutes and the BIPM participated. Participants were required to assign the mass fraction of estradiol present as the main component in the comparison sample (CCQM-K55.a) which consisted of a bulk estradiol hemihydrate material obtained from a commercial supplier that had been extensively but not exhaustively dried prior to sub-division into the units supplied for the comparison. Estradiol was selected to be representative of the performance of a laboratory's measurement capability for the purity assignment of organic compounds of medium structural complexity [molar mass range 300-500 Da] and low polarity (pKOW < -2) for which related structure impurities can be quantified by capillary gas phase chromatography (GC) or by high performance liquid chromatography (LC). The majority of participants used a mass balance approach to determine the estradiol content. The key comparison reference value (KCRV) for estradiol in CCQM-K55.a was assigned by combination of KCRVs assigned by consensus from participant results for each orthogonal impurity class. This allowed participants to demonstrate the efficacy (or otherwise) of their implementation of the mass balance approach and to demonstrate that their assigned value for the main component agreed with the KCRV through use of internally consistent contributing methods. The KCRV for the estradiol content of the material was 984.3 mg/g with a combined standard uncertainty of 0.42 mg/g. The individual participant results showed that a relative expanded uncertainty for the purity assignment of 0.2% is a reasonable estimate of the best achievable result by an individual laboratory for a material of this complexity available in this amount at this level of

  15. Eigenstate thermalization hypothesis in quantum dimer models

    NASA Astrophysics Data System (ADS)

    Lan, Zhihao; Powell, Stephen

    2017-09-01

    We use exact diagonalization to study the eigenstate thermalization hypothesis (ETH) in the quantum dimer model on the square and triangular lattices. Due to the nonergodicity of the local plaquette-flip dynamics, the Hilbert space, which consists of highly constrained close-packed dimer configurations, splits into sectors characterized by topological invariants. We show that this has important consequences for ETH: We find that ETH is clearly satisfied only when each topological sector is treated separately, and only for moderate ratios of the potential and kinetic terms in the Hamiltonian. By contrast, when the spectrum is treated as a whole, ETH breaks down on the square lattice and, apparently, also on the triangular lattice. These results demonstrate that quantum dimer models have interesting thermalization dynamics.

  16. Clustering of Nonergodic Eigenstates in Quantum Spin Glasses.

    PubMed

    Baldwin, C L; Laumann, C R; Pal, A; Scardicchio, A

    2017-03-24

    The two primary categories for eigenstate phases of matter at a finite temperature are many-body localization (MBL) and the eigenstate thermalization hypothesis (ETH). We show that, in the paradigmatic quantum p-spin models of the spin-glass theory, eigenstates violate the ETH yet are not MBL either. A mobility edge, which we locate using the forward-scattering approximation and replica techniques, separates the nonergodic phase at a small transverse field from an ergodic phase at a large transverse field. The nonergodic phase is also bounded from above in temperature, by a transition in configuration-space statistics reminiscent of the clustering transition in the spin-glass theory. We show that the nonergodic eigenstates are organized in clusters which exhibit distinct magnetization patterns, as characterized by an eigenstate variant of the Edwards-Anderson order parameter.

  17. Clustering of Nonergodic Eigenstates in Quantum Spin Glasses

    NASA Astrophysics Data System (ADS)

    Baldwin, C. L.; Laumann, C. R.; Pal, A.; Scardicchio, A.

    2017-03-01

    The two primary categories for eigenstate phases of matter at a finite temperature are many-body localization (MBL) and the eigenstate thermalization hypothesis (ETH). We show that, in the paradigmatic quantum p -spin models of the spin-glass theory, eigenstates violate the ETH yet are not MBL either. A mobility edge, which we locate using the forward-scattering approximation and replica techniques, separates the nonergodic phase at a small transverse field from an ergodic phase at a large transverse field. The nonergodic phase is also bounded from above in temperature, by a transition in configuration-space statistics reminiscent of the clustering transition in the spin-glass theory. We show that the nonergodic eigenstates are organized in clusters which exhibit distinct magnetization patterns, as characterized by an eigenstate variant of the Edwards-Anderson order parameter.

  18. Simultaneous determination of various cardiac glycosides by liquid chromatography-hybrid mass spectrometry for the purity assessment of the therapeutic monitored drug digoxin.

    PubMed

    Josephs, Ralf Dieter; Daireaux, Adeline; Westwood, Steven; Wielgosz, Robert Ian

    2010-07-02

    A high performance liquid chromatography-hybrid tandem mass spectrometry (LC-MS(n)) method utilising electrospray ionisation has been developed and implemented for the simultaneous determination of several cardiac glycosides (CGs) as well as their corresponding aglycones formed by and extracted from herbaceous plants of the genus Digitalis. The method has been validated in-house and its performance characteristics (linearity, repeatability, limits of detection, etc.) were assessed for use in the quantification of CGs and their corresponding aglycones. LODs from 38 to 936pgg(-1) in solution, corresponding to mass fraction impurity levels from 0.0009 (or 0.00008%) to 0.019mgg(-1) (or 0.0019%) detectable in the pure materials have been realized. Moreover, the method was used to characterize and to determine the inherent CG impurities in batches of the therapeutic monitored drug digoxin which served as candidate reference material for an organic purity assessment inter-laboratory study (CCQM-P20.f) organised by the BIPM Chemistry Section and carried out within the framework of the Organic Analysis Working Group (OAWG) of the Consultative Committee for Amount of Substance - Metrology in Chemistry (CCQM). Digoxin was selected from materials required for the establishment of reference measurement systems for clinical chemistry and laboratory medicine.

  19. Thermalization without eigenstate thermalization hypothesis after a quantum quench

    NASA Astrophysics Data System (ADS)

    Mori, Takashi; Shiraishi, Naoto

    2017-08-01

    Nonequilibrium dynamics of a nonintegrable system without the eigenstate thermalization hypothesis is studied. It is shown that, in the thermodynamic limit, this model thermalizes after an arbitrary quantum quench at finite temperature, although it does not satisfy the eigenstate thermalization hypothesis. In contrast, when the system size is finite and the temperature is low enough, the system may not thermalize. In this case, the steady state is well described by the generalized Gibbs ensemble constructed by using highly nonlocal conserved quantities. We also show that this model exhibits prethermalization, in which the prethermalized state is characterized by nonthermal energy eigenstates.

  20. Final report on key comparison CCQM-K55.b (aldrin): An international comparison of mass fraction purity assignment of aldrin

    NASA Astrophysics Data System (ADS)

    Westwood, Steven; Josephs, Ralf; Choteau, Tiphaine; Daireaux, Adeline; Mesquida, Charline; Wielgosz, Robert; Rosso, Adriana; Ruiz de Arechavaleta, Mariana; Davies, Stephen; Wang, Hongjie; Pires do Rego, Eliane Cristina; Marques Rodrigues, Janaína; de Freitas Guimarães, Evelyn; Vinicius Barreto Sousa, Marcus; Monteiro, Tânia Maria; Alves das Neves Valente, Laura; Marques Violante, Fernando Gustavo; Rubim Ribeiro Almeida, Renato; Baptista Quaresma, Maria Cristina; Nogueira, Raquel; Windust, Anthony; Dai, Xinhua; Li, Xiaomin; Zhang, Wei; Li, Ming; Shao, Mingwu; Wei, Chao; Wong, Siu-kay; Cabillic, Julie; Gantois, Fanny; Philipp, Rosemarie; Pfeifer, Dietmar; Hein, Sebastian; Klyk-Seitz, Urszula-Anna; Ishikawa, Keiichiro; Castro, Esther; Gonzalez, Norma; Krylov, Anatoly; Tang Lin, Teo; Tong Kooi, Lee; Fernandes-Whaley, M.; Prévoo, D.; Archer, M.; Visser, R.; Nlhapo, N.; de Vos, B.; Ahn, Seonghee; Pookrod, Preeyaporn; Wiangnon, Kanjana; Sudsiri, Nittaya; Muaksang, Kittiya; Cherdchu, Chainarong; Ceyhan Gören, Ahmet; Bilsel, Mine; LeGoff, Thierry; Bearden, Dan; Bedner, Mary; Duewer, David; Hancock, Diane; Lang, Brian; Lippa, Katrice; Schantz, Michele; Sieber, John

    2012-01-01

    Under the auspices of the Organic Analysis Working Group (OAWG) of the Comité Consultatif pour la Quantité de Matière (CCQM) a key comparison, CCQM K55.b, was coordinated by the Bureau International des Poids et Mesures (BIPM) in 2010/2011. Nineteen national measurement institutes and the BIPM participated. Participants were required to assign the mass fraction of aldrin present as the main component in the comparison sample for CCQM-K55.b which consisted of technical grade aldrin obtained from the National Measurement Institute Australia that had been subject to serial recrystallization and drying prior to sub-division into the units supplied for the comparison. Aldrin was selected to be representative of the performance of a laboratory's measurement capability for the purity assignment of organic compounds of medium structural complexity [molar mass range 300 Da to 500 Da] and low polarity (pKOW < -2) for which related structure impurities can be quantified by capillary gas phase chromatography (GC). The key comparison reference value (KCRV) for the aldrin content of the material was 950.8 mg/g with a combined standard uncertainty of 0.85 mg/g. The KCRV was assigned by combination of KCRVs assigned by consensus from participant results for each orthogonal impurity class. The relative expanded uncertainties reported by laboratories having results consistent with the KCRV ranged from 0.3% to 0.6% using a mass balance approach and 0.5% to 1% using a qNMR method. The major analytical challenge posed by the material proved to be the detection and quantification of a significant amount of oligomeric organic material within the sample and most participants relying on a mass balance approach displayed a positive bias relative to the KCRV (overestimation of aldrin content) in excess of 10 mg/g due to not having adequate procedures in place to detect and quantify the non-volatile content—specifically the non-volatile organics content—of the comparison sample. There

  1. Normal phase-liquid chromatography-tandem mass spectrometry with atmospheric pressure photoionization for the purity assessment of 17β-estradiol.

    PubMed

    Josephs, Ralf Dieter; Daireaux, Adeline; Choteau, Tiphaine; Westwood, Steven; Wielgosz, Robert Ian

    2015-04-01

    A normal phase-liquid chromatography-hybrid tandem mass spectrometry (NP-LC-MS/MS) method utilizing atmospheric pressure photoionization (APPI) without dopant has been developed and implemented for the simultaneous determination of several estrogenic steroid hormones. The combination of both NP-LC and APPI-MS/MS tolerates the use of solvents that have the advantages of being self-doping for APPI and, at the same time, inhibit the in situ formation of estrogen dimers as frequently observed for conventional reversed phase (RP)-LC methods. The NP-LC-APPI-MS/MS method has been validated in-house, and its performance characteristics (linearity, repeatability, limits of detection, etc.) were assessed for use in the quantification of estrogens. Moreover, the method was used to characterize and determine the inherent related structure impurities in batches of β-estradiol, required for the establishment of reference measurement systems for clinical chemistry and laboratory medicine, which served as candidate reference material for an organic purity assessment interlaboratory study (CCQM-K55.a) organized by the International Bureau of Weights and Measures (BIPM) Chemistry Department and carried out within the framework of the Organic Analysis Working Group (OAWG) of the Consultative Committee for Amount of Substance-Metrology in Chemistry (CCQM).

  2. Development and validation of a supercritical fluid chromatography method for the direct determination of enantiomeric purity of provitamin B5 in cosmetic formulations with mass spectrometric detection.

    PubMed

    Khater, Syame; West, Caroline

    2015-01-01

    A rapid and efficient chiral supercritical fluid chromatography (SFC) method has been developed for the quantitative determination of panthenol enantiomers in cosmetic formulations (cream, lotion, wipe, and exfoliant). Indeed, the pharmacological effect only depends on the D form (Dexpanthenol) thus accurate measurement of its enantiomeric purity in formulated cosmetic products is of interest. The samples were prepared with liquid-liquid extraction followed by solid-phase extraction on Adsorbex amino cartridges. After testing several enantioselective columns in an attempt at reversing the elution order to have the minor enantiomer eluted first, the best separation of enantiomers and internal standard (N-acetyl-L-alanine) was achieved on a 3 μm-amylose-type immobilized polysaccharide chiral stationary phase (Chiralpak IA) in less than 6 min with a simple mobile phase comprising carbon dioxide and 11% methanol pumped at 2.3 mL/min, 25°C and 150 bar backpressure. Supercritical fluid chromatography coupled to both an optical diode-array detector and a user-friendly single-quadrupole mass spectrometer (Waters QDa) equipped with electrospray ionization source has been used. The on-line coupling ensures the technique to be more informative and improves detection sensitivity, as underivatized panthenol has a poor UV absorption. The limit of quantification (LOQ) achieved with single-ion recording was 0.5 μg/mL. The method was validated in terms of linearity, precision and accuracy and satisfactory results were obtained.

  3. Interplay of gravitation and linear superposition of different mass eigenstates

    SciTech Connect

    Ahluwalia, D.V. |; Burgard, C.

    1998-04-01

    The interplay of gravitation and the quantum-mechanical principle of linear superposition induces a new set of neutrino oscillation phases. These ensure that the flavor-oscillation clocks, inherent in the phenomenon of neutrino oscillations, redshift precisely as required by Einstein{close_quote}s theory of gravitation. The physical observability of these phases in the context of the solar neutrino anomaly, type-II supernova, and certain atomic systems is briefly discussed. {copyright} {ital 1998} {ital The American Physical Society}

  4. APPARATUS FOR HIGH PURITY METAL RECOVERY

    DOEpatents

    Magel, T.T.

    1959-02-10

    An apparatus is described for preparing high purity metal such as uranium, plutonium and the like from an impure mass of the same metal. The apparatus is arranged so that the impure metal is heated and swept by a stream of hydrogen gas bearing a halogen such as iodine. The volatiie metal halide formed is carried on to a hot filament where the metal halide is decomposed and the molten high purity metal is collected in a rceeiver below

  5. Entanglement Entropy of Eigenstates of Quadratic Fermionic Hamiltonians

    NASA Astrophysics Data System (ADS)

    Vidmar, Lev; Hackl, Lucas; Bianchi, Eugenio; Rigol, Marcos

    2017-07-01

    In a seminal paper [D. N. Page, Phys. Rev. Lett. 71, 1291 (1993), 10.1103/PhysRevLett.71.1291], Page proved that the average entanglement entropy of subsystems of random pure states is Save≃ln DA-(1 /2 )DA2/D for 1 ≪DA≤√{D }, where DA and D are the Hilbert space dimensions of the subsystem and the system, respectively. Hence, typical pure states are (nearly) maximally entangled. We develop tools to compute the average entanglement entropy ⟨S ⟩ of all eigenstates of quadratic fermionic Hamiltonians. In particular, we derive exact bounds for the most general translationally invariant models ln DA-(ln DA)2/ln D ≤⟨S ⟩≤ln DA-[1 /(2 ln 2 )](ln DA)2/ln D . Consequently, we prove that (i) if the subsystem size is a finite fraction of the system size, then ⟨S ⟩eigenstates of the Hamiltonian departs from the result for typical pure states, and (ii) in the limit in which the subsystem size is a vanishing fraction of the system size, the average entanglement entropy is maximal; i.e., typical eigenstates of such Hamiltonians exhibit eigenstate thermalization.

  6. Assignment of purity to primary metal calibrants using pin-cell VG 9000 glow discharge mass spectrometry: a primary method with direct traceability to the SI international system of units?

    NASA Astrophysics Data System (ADS)

    Sturgeon, R. E.; Methven, B.; Willie, S. N.; Grinberg, P.

    2014-10-01

    A measurement model based on the use of a pin-cell glow discharge source coupled to a VG 9000 sector field mass spectrometer (GD-MS) for the assignment of purity of high-purity metals, i.e., mass fraction of metal matrix, w(M), is presented. A mass balance approach to the calculation requires the determination and summation of impurity mass fractions of all extraneous elements present, including non-metals and gases. It is posited that a primary method of measurement can be devised to yield direct traceability of results to the SI. The major source of uncertainty in the traceability chain stems from the need to adjust the initially estimated quantity values of each impurity element by a relative sensitivity factor ‘influence quantity’ (RSF_{M}^{e} ) , derived from ab initio calculations, and validated through comparison with those derived through use of Certified Reference Materials. It is argued that the method is sufficiently well understood that a measurement equation can be formulated for which all parameters are measured in terms of SI units; that all contributions to uncertainty of measurement can be quantitatively evaluated, underpinning the metrological traceability; and that the performance of GD-MS in CCQM key and pilot comparisons of trace elements in complex metal matrices is in conformance with claimed capabilities. The applicability of the approach to metals in the 3N to 7N range of purity shows that fit-for-purpose relative expanded uncertainties of 0.5% to 0.000 05% can be conservatively achieved for w(M). Presentation of various instrument calibration scenarios vis-à-vis impact on SI traceability of results is also undertaken with a view to eliciting further discussion of this concept within the metrological community.

  7. High purity tungsten targets

    NASA Technical Reports Server (NTRS)

    1975-01-01

    High purity tungsten, which is used for targets in X-ray tubes was considered for space processing. The demand for X-ray tubes was calculated using the growth rates for dental and medical X-ray machines. It is concluded that the cost benefits are uncertain.

  8. High purity tungsten targets

    NASA Technical Reports Server (NTRS)

    1975-01-01

    High purity tungsten, which is used for targets in X-ray tubes was considered for space processing. The demand for X-ray tubes was calculated using the growth rates for dental and medical X-ray machines. It is concluded that the cost benefits are uncertain.

  9. Quantum localization of chaotic eigenstates and the level spacing distribution

    NASA Astrophysics Data System (ADS)

    Batistić, Benjamin; Robnik, Marko

    2013-11-01

    The phenomenon of quantum localization in classically chaotic eigenstates is one of the main issues in quantum chaos (or wave chaos), and thus plays an important role in general quantum mechanics or even in general wave mechanics. In this work we propose two different localization measures characterizing the degree of quantum localization, and study their relation to another fundamental aspect of quantum chaos, namely the (energy) spectral statistics. Our approach and method is quite general, and we apply it to billiard systems. One of the signatures of the localization of chaotic eigenstates is a fractional power-law repulsion between the nearest energy levels in the sense that the probability density to find successive levels on a distance S goes like ∝Sβ for small S, where 0≤β≤1, and β=1 corresponds to completely extended states. We show that there is a clear functional relation between the exponent β and the two different localization measures. One is based on the information entropy and the other one on the correlation properties of the Husimi functions. We show that the two definitions are surprisingly linearly equivalent. The approach is applied in the case of a mixed-type billiard system [M. Robnik, J. Phys. A: Math. Gen.JPHAC50305-447010.1088/0305-4470/16/17/014 16, 3971 (1983)], in which the separation of regular and chaotic eigenstates is performed.

  10. Emergent Eigenstate Solution to Quantum Dynamics Far from Equilibrium

    NASA Astrophysics Data System (ADS)

    Vidmar, Lev; Iyer, Deepak; Rigol, Marcos

    2017-04-01

    The quantum dynamics of interacting many-body systems has become a unique venue for the realization of novel states of matter. Here, we unveil a new class of nonequilibrium states that are eigenstates of an emergent local Hamiltonian. The latter is explicitly time dependent and, even though it does not commute with the physical Hamiltonian, it behaves as a conserved quantity of the time-evolving system. We discuss two examples of integrable systems in which the emergent eigenstate solution can be applied for an extensive (in system size) time: transport in one-dimensional lattices with initial particle (or spin) imbalance and sudden expansion of quantum gases in optical lattices. We focus on noninteracting spinless fermions, hard-core bosons, and the Heisenberg model. We show that current-carrying states can be ground states of emergent local Hamiltonians, and that they can exhibit a quasimomentum distribution function that is peaked at nonzero (and tunable) quasimomentum. We also show that time-evolving states can be highly excited eigenstates of emergent local Hamiltonians, with an entanglement entropy that does not exhibit volume-law scaling.

  11. Purity assessment of crystalline zearalenone.

    PubMed

    Krska, Rudolf; Welzig, Elvira; Josephs, Ralf D; Kandler, Wolfgang; Pettersson, Hans; MacDonald, Susan; Charlton, Adrian; Brereton, Paul; Hametner, Christian; Berner, Diana; Zöllner, Peter

    2003-01-01

    Commercially available solid zearalenone (ZON) to be used as a certified liquid calibrant (BCR-699) in a project funded by the European Commission within the Standard Measurement and Testing program was characterized and its purity determined. The degree of purity of the ZON was examined by UV spectrophotometer, liquid chromatography (LC) with diode array and fluorescence detection, 1H and 13C-NMR spectrometry, LC-mass spectrometry (LC/MS/MS), ion chromatography (IC), and differential scanning calorimetry (DSC). The diagrams obtained from DSC analysis and the UV spectrum showed no detectable impurities. Likewise, no impurities were observed by LC analysis with both diode array and fluorescence detection. IC determination revealed negligible contamination of ZON with chloride of 0.020 +/- 0.005% and nitrate of 0.016 +/- 0.006%. Zearalanone (ZAN) was identified as one of 2 minor (0.2%) impurities by LC/MS/MS. The 1H-NMR measurements revealed an additional peak, which has not been previously reported in the literature. It could be identified as part of the ZON spectrum as the signal arising from the phenolic proton attached to C4'. The manufacturer states an additional contamination with 0.2% methylene chloride, which could be confirmed to an extent of 0.1% by 1H-NMR. Minor impurities, whose structures remain unknown, were discovered at 3.5 and < 1 ppm. Total percentage of impurities based on NMR measurement was estimated not to exceed 1%. A purity of 99.5% with a tolerance of +/- 0.5% was finally attributed to the ZON studied in this project.

  12. Extended Hellmann-Feynman theorem for degenerate eigenstates

    NASA Astrophysics Data System (ADS)

    Zhang, G. P.; George, Thomas F.

    2004-04-01

    In a previous paper, we reported a failure of the traditional Hellmann-Feynman theorem (HFT) for degenerate eigenstates. This has generated enormous interest among different groups. In four independent papers by Fernandez, by Balawender, Hola, and March, by Vatsya, and by Alon and Cederbaum, an elegant method to solve the problem was devised. The main idea is that one has to construct and diagonalize the force matrix for the degenerate case, and only the eigenforces are well defined. We believe this is an important extension to HFT. Using our previous example for an energy level of fivefold degeneracy, we find that those eigenforces correctly reflect the symmetry of the molecule.

  13. Random Free Fermions: An Analytical Example of Eigenstate Thermalization

    NASA Astrophysics Data System (ADS)

    Magán, Javier M.

    2016-01-01

    Having analytical instances of the eigenstate thermalization hypothesis (ETH) is of obvious interest, both for fundamental and applied reasons. This is generally a hard task, due to the belief that nonlinear interactions are basic ingredients of the thermalization mechanism. In this article we prove that random Gaussian-free fermions satisfy ETH in the multiparticle sector, by analytically computing the correlations and entanglement entropies of the theory. With the explicit construction at hand, we finally comment on the differences between fully random Hamiltonians and random Gaussian systems, providing a physically motivated notion of randomness of the microscopic quantum state.

  14. CP violation in neutral B decays to non-CP-eigenstates

    SciTech Connect

    Kayser, B.

    1992-12-31

    If CP violation comes from complex phases in the quark mixing matrix, then neutral B decays to CP eigenstates will exhibit large, cleanly-predicted CP-violating effects. The authors show that the same is true of neutral B decays to several types of ``near-CP-eigenstates.`` By experimentally studying the latter decays as well as those to the CP eigenstates, one will be able to obtain more definitive information on CP violation from a given number of B mesons.

  15. 1,1-dimethylhydrazine as a high purity nitrogen source for MOVPE-water reduction and quantification using nuclear magnetic resonance, gas chromatography-atomic emission detection spectroscopy and cryogenic-mass spectroscopy analytical techniques

    SciTech Connect

    Odedra, R.; Smith, L.M.; Rushworth, S.A.

    2000-01-01

    Hydrazine derivatives are attractive low temperature nitrogen sources for use in MOVPE due to their low thermal stability. However their purification and subsequent analysis has not previously been investigated in depth for this application. A detailed study on 1,1-dimethylhydrazine {l{underscore}brace}(CH{sub 3}){sub 2}N-NH{sub 2}{r{underscore}brace} purified by eight different methods and the subsequent quantitative measurements of water present in the samples obtained is reported here. A correlation between {sup 1}H nuclear magnetic resonance spectroscopy (NMR), gas chromatography-atomic emission detection (GC-AED) and cryogenic mass spectroscopy (Cryogenic-MS) has been performed. All three analysis techniques can be used to measure water in the samples and with the best purification the water content can be lowered well below 100 ppm. The high purity of this material has been demonstrated by growth results and the state-of-the-art performance of laser diodes.

  16. Communication: Observation of local-bender eigenstates in acetylene.

    PubMed

    Steeves, Adam H; Park, G Barratt; Bechtel, Hans A; Baraban, Joshua H; Field, Robert W

    2015-08-21

    We report the observation of eigenstates that embody large-amplitude, local-bending vibrational motion in acetylene by stimulated emission pumping spectroscopy via vibrational levels of the S1 state involving excitation in the non-totally symmetric bending modes. The N(b) = 14 level, lying at 8971.69 cm(-1) (J = 0), is assigned on the basis of degeneracy due to dynamical symmetry breaking in the local-mode limit. The level pattern for the N(b) = 16 level, lying at 10 218.9 cm(-1), is consistent with expectations for increased separation of ℓ = 0 and 2 vibrational angular momentum components. Increasingly poor agreement between our observations and the predicted positions of these levels highlights the failure of currently available normal mode effective Hamiltonian models to extrapolate to regions of the potential energy surface involving large-amplitude displacement along the acetylene ⇌ vinylidene isomerization coordinate.

  17. Firewalls from double purity

    NASA Astrophysics Data System (ADS)

    Bousso, Raphael

    2013-10-01

    The firewall paradox is often presented as arising from double entanglement, but I argue that more generally the paradox is double purity. Near-horizon modes are purified by the interior, in the infalling vacuum. Hence, they cannot also be pure alone, or in combination with any third system, as demanded by unitarity. This conflict arises independently of the Page time, for entangled and for pure states. It implies that identifications of Hilbert spaces cannot resolve the paradox. Traditional complementarity requires the unitary identification of infalling matter with a scrambled subsystem of the Hawking radiation. Extending this map to the infalling vacuum overdetermines the out-state. More general complementarity maps (“A=RB,” “ER=EPR”) necessarily fail when the near-horizon zone is pure. I argue that pure-zone states span the microcanonical ensemble, and that this suffices to make the horizon a special place. I advocate that the ability to detect the horizon locally, rather than the degree or probability of violence, is what makes firewalls problematic. Conversely, if the production of matter at the horizon can be dynamically understood and shown to be consistent, then firewalls do not constitute a violation of the equivalence principle.

  18. An international comparison of mass fraction purity assignment of digoxin: The Comité Consultatif pour la Quantité de Matière (CCQM) Pilot Study CCQM-P20.f (Digoxin)

    NASA Astrophysics Data System (ADS)

    Westwood, S.; Josephs, R.; Choteau, T.; Mesquida, C.; Daireaux, A.; Wielgosz, R.; Davies, S.; Windust, A.; Kang, M.; Ting, H.; Kato, K.; Frias, E.; Pérez, M.; Apps, P.; Fernandes-Whaley, M.; Wiangnon, K.; Ruangrittinon, N.; Wood, S.; LeGoff, T.; Duewer, D.; Schantz, M.; Siekmann, L.; Esker, J.

    2011-01-01

    results. Unlike the CCQM-P20.e samples, in which the major impurities were solely related structure organic compounds, the CCQM-P20.f study material contained significant levels of residual organic solvents (ethanol, dichloromethane and to a lesser extent toluene). The majority of participants failed to detect and allow for the presence of this class of impurity, introducing a bias towards overestimation of digoxin content in most of the individual results. However, the uncertainty budgets produced by several participants were sufficiently conservative such that their reported results were nevertheless consistent with the reference value for digoxin content assigned using a consensus mass balance approach. The results of the comparison reinforce the conclusion from previous rounds of the CCQM-P20 study that care in developing and validating the suitability of the chromatographic separation method used to resolve the main component from the related structure impurities present is essential to obtaining reliable, comparable results when using the mass balance approach to estimate purity. This specific comparison has demonstrated that, in addition to developing an appropriate chromatographic separation, it is also important to use complementary techniques capable of detecting all potential orthogonal classes of impurities if it is desired to demonstrate a general capability to assign purity with a small (<0.2% relative) standard uncertainty. Main text. To reach the main text of this paper, click on Final Report. The final report has been peer-reviewed and approved for publication by the CCQM OAWG.

  19. Subsystem eigenstate thermalization hypothesis for entanglement entropy in CFT

    NASA Astrophysics Data System (ADS)

    He, Song; Lin, Feng-Li; Zhang, Jia-ju

    2017-08-01

    We investigate a weak version of subsystem eigenstate thermalization hypothesis (ETH) for a two-dimensional large central charge conformal field theory by comparing the local equivalence of high energy state and thermal state of canonical ensemble. We evaluate the single-interval Rényi entropy and entanglement entropy for a heavy primary state in short interval expansion. We verify the results of Rényi entropy by two different replica methods. We find nontrivial results at the eighth order of short interval expansion, which include an infinite number of higher order terms in the large central charge expansion. We then evaluate the relative entropy of the reduced density matrices to measure the difference between the heavy primary state and thermal state of canonical ensemble, and find that the aforementioned nontrivial eighth order results make the relative entropy unsuppressed in the large central charge limit. By using Pinsker's and Fannes-Audenaert inequalities, we can exploit the results of relative entropy to yield the lower and upper bounds on trace distance of the excited-state and thermal-state reduced density matrices. Our results are consistent with subsystem weak ETH, which requires the above trace distance is of power-law suppression by the large central charge. However, we are unable to pin down the exponent of power-law suppression. As a byproduct we also calculate the relative entropy to measure the difference between the reduced density matrices of two different heavy primary states.

  20. Elimination of chromatographic and mass spectrometric problems in GC-MS analysis of Lavender essential oil by multivariate curve resolution techniques: Improving the peak purity assessment by variable size moving window-evolving factor analysis.

    PubMed

    Jalali-Heravi, Mehdi; Moazeni-Pourasil, Roudabeh Sadat; Sereshti, Hassan

    2015-03-01

    In analysis of complex natural matrices by gas chromatography-mass spectrometry (GC-MS), many disturbing factors such as baseline drift, spectral background, homoscedastic and heteroscedastic noise, peak shape deformation (non-Gaussian peaks), low S/N ratio and co-elution (overlapped and/or embedded peaks) lead the researchers to handle them to serve time, money and experimental efforts. This study aimed to improve the GC-MS analysis of complex natural matrices utilizing multivariate curve resolution (MCR) methods. In addition, to assess the peak purity of the two-dimensional data, a method called variable size moving window-evolving factor analysis (VSMW-EFA) is introduced and examined. The proposed methodology was applied to the GC-MS analysis of Iranian Lavender essential oil, which resulted in extending the number of identified constituents from 56 to 143 components. It was found that the most abundant constituents of the Iranian Lavender essential oil are α-pinene (16.51%), camphor (10.20%), 1,8-cineole (9.50%), bornyl acetate (8.11%) and camphene (6.50%). This indicates that the Iranian type Lavender contains a relatively high percentage of α-pinene. Comparison of different types of Lavender essential oils showed the composition similarity between Iranian and Italian (Sardinia Island) Lavenders. Published by Elsevier B.V.

  1. Eigenstate thermalization in the two-dimensional transverse field Ising model.

    PubMed

    Mondaini, Rubem; Fratus, Keith R; Srednicki, Mark; Rigol, Marcos

    2016-03-01

    We study the onset of eigenstate thermalization in the two-dimensional transverse field Ising model (2D-TFIM) in the square lattice. We consider two nonequivalent Hamiltonians: the ferromagnetic 2D-TFIM and the antiferromagnetic 2D-TFIM in the presence of a uniform longitudinal field. We use full exact diagonalization to examine the behavior of quantum chaos indicators and of the diagonal matrix elements of operators of interest in the eigenstates of the Hamiltonian. An analysis of finite size effects reveals that quantum chaos and eigenstate thermalization occur in those systems whenever the fields are nonvanishing and not too large.

  2. Analysis of trace halocarbon contaminants in ultra high purity helium

    NASA Technical Reports Server (NTRS)

    Fewell, Larry L.

    1994-01-01

    This study describes the analysis of ultra high purity helium. Purification studies were conducted and containment removal was effected by the utilization of solid adsorbent purge-trap systems at cryogenic temperatures. Volatile organic compounds in ultra high purity helium were adsorbed on a solid adsorbent-cryogenic trap, and thermally desorbed trace halocarbon and other contaminants were analyzed by combined gas chromatography-mass spectrometry.

  3. Coherent Preparation of Molecular Hydrogen in (v, J,M) Eigenstates for Reaction Dynamics Studies

    DTIC Science & Technology

    2016-08-05

    for preparing single vibrational energy eigenstate of a molecule. Using SARP we have, for the first time, demonstrated population inversion between a...information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. Stanford University 3160 Porter...eigenstate of a molecule. Using SARP we have, for the first time, demonstrated population inversion between a ground vibrational (v=0, J) and an

  4. Targeting eigenstates using a decoherence-based nonlinear Schrödinger equation

    NASA Astrophysics Data System (ADS)

    Furtmaier, O.; Mendoza, M.

    2017-08-01

    Inspired by the idea of mimicking the measurement on a quantum system through a decoherence process to target specific eigenstates based on Born's law, i.e., the hierarchy of probabilities instead of the hierarchy of eigenvalues, we transform a Lindblad equation for the reduced density operator into a nonlinear Schrödinger equation to obtain a computationally feasible simulation of the decoherent dynamics in the open quantum system. This gives the opportunity to target the eigenstates which have the largest L2 overlap with an initial superposition state and hence more flexibility in the selection criteria. One can use this feature, for instance, to approximate eigenstates with certain localization or symmetry properties. As an application of the theory we discuss eigenstate towing, which relies on the perturbation theory to follow the progression of an arbitrary subset of eigenstates along a sum of perturbation operators with the intention to explore, for example, the effect of interactions on these eigenstates. The easily parallelizable numerical method shows an exponential convergence and its computational costs scale linearly for sparse matrix representations of the involved Hermitian operators.

  5. Enhanced Detection of Low-Abundance Host Cell Protein Impurities in High-Purity Monoclonal Antibodies Down to 1 ppm Using Ion Mobility Mass Spectrometry Coupled with Multidimensional Liquid Chromatography.

    PubMed

    Doneanu, Catalin E; Anderson, Malcolm; Williams, Brad J; Lauber, Matthew A; Chakraborty, Asish; Chen, Weibin

    2015-10-20

    The enormous dynamic range of proteinaceous species present in protein biotherapeutics poses a significant challenge for current mass spectrometry (MS)-based methods to detect low-abundance HCP impurities. Previously, an HCP assay based on two-dimensional chromatographic separation (high pH/low pH) coupled to high-resolution quadrupole time-of-flight (QTOF) mass spectrometry and developed in the author's laboratory has been shown to achieve a detection limit of about 50 ppm (parts per milion) for the identification and quantification of HCPs present in monoclonal antibodies following Protein A purification.1 To improve the HCP detection limit we have explored the utility of several new analytical techniques for HCP analysis and thereby developed an improved liquid chromatography-mass spectrometry (LC-MS) methodology for enhanced detection of HCPs. The new method includes (1) the use of a new charge-surface-modified (CSH) C18 stationary phase to mitigate the challenges of column saturation, peak tailing, and distortion that are commonly observed in the HCP analysis; (2) the incorporation of traveling-wave ion mobility (TWIM) separation of coeluting peptide precursors, and (3) the improvement of fragmentation efficiency of low-abundance HCP peptides by correlating the collision energy used for precursor fragmentation with their mobility drift time. As a result of these improvements, the detection limit of the new methodology was greatly improved, and HCPs present at a concentration as low as 1 ppm (1 ng HCP/mg mAb) were successfully identified and quantified. The newly developed method was applied to analyze two high-purity mAbs (NIST mAb and Infliximab) expressed in a murine cell line. For both samples, low-abundance HCPs (down to 1 ppm) were confidently identified, and the identities of the HCPs were further confirmed by targeted MS/MS experiments. In addition, the performance of the assay was evaluated by an interlaboratory study in which three independent

  6. Finding Matrix Product State Representations of Highly Excited Eigenstates of Many-Body Localized Hamiltonians

    NASA Astrophysics Data System (ADS)

    Yu, Xiongjie; Pekker, David; Clark, Bryan K.

    2017-01-01

    A key property of many-body localized Hamiltonians is the area law entanglement of even highly excited eigenstates. Matrix product states (MPS) can be used to efficiently represent low entanglement (area law) wave functions in one dimension. An important application of MPS is the widely used density matrix renormalization group (DMRG) algorithm for finding ground states of one-dimensional Hamiltonians. Here, we develop two algorithms, the shift-and-invert MPS (SIMPS) and excited state DMRG which find highly excited eigenstates of many-body localized Hamiltonians. Excited state DMRG uses a modified sweeping procedure to identify eigenstates, whereas SIMPS applies the inverse of the shifted Hamiltonian to a MPS multiple times to project out the targeted eigenstate. To demonstrate the power of these methods, we verify the breakdown of the eigenstate thermalization hypothesis in the many-body localized phase of the random field Heisenberg model, show the saturation of entanglement in the many-body localized phase, and generate local excitations.

  7. The Liquid Argon Purity Demonstrator

    SciTech Connect

    Adamowski, M.; Carls, B.; Dvorak, E.; Hahn, A.; Jaskierny, W.; Johnson, C.; Jostlein, H.; Kendziora, C.; Lockwitz, S.; Pahlka, B.; Plunkett, R.; Pordes, S.; Rebel, B.; Schmitt, R.; Stancari, M.; Tope, T.; Voirin, E.; Yang, T.

    2014-07-01

    The Liquid Argon Purity Demonstrator was an R&D test stand designed to determine if electron drift lifetimes adequate for large neutrino detectors could be achieved without first evacuating the cryostat. We describe here the cryogenic system, its operations, and the apparatus used to determine the contaminant levels in the argon and to measure the electron drift lifetime. The liquid purity obtained by this system was facilitated by a gaseous argon purge. Additionally, gaseous impurities from the ullage were prevented from entering the liquid at the gas-liquid interface by condensing the gas and filtering the resulting liquid before returning to the cryostat. The measured electron drift lifetime in this test was greater than 6 ms, sustained over several periods of many weeks. Measurements of the temperature profile in the argon, to assess convective flow and boiling, were also made and are compared to simulation.

  8. Iodine Absorption Cells Purity Testing.

    PubMed

    Hrabina, Jan; Zucco, Massimo; Philippe, Charles; Pham, Tuan Minh; Holá, Miroslava; Acef, Ouali; Lazar, Josef; Číp, Ondřej

    2017-01-06

    This article deals with the evaluation of the chemical purity of iodine-filled absorption cells and the optical frequency references used for the frequency locking of laser standards. We summarize the recent trends and progress in absorption cell technology and we focus on methods for iodine cell purity testing. We compare two independent experimental systems based on the laser-induced fluorescence method, showing an improvement of measurement uncertainty by introducing a compensation system reducing unwanted influences. We show the advantages of this technique, which is relatively simple and does not require extensive hardware equipment. As an alternative to the traditionally used methods we propose an approach of hyperfine transitions' spectral linewidth measurement. The key characteristic of this method is demonstrated on a set of testing iodine cells. The relationship between laser-induced fluorescence and transition linewidth methods will be presented as well as a summary of the advantages and disadvantages of the proposed technique (in comparison with traditional measurement approaches).

  9. Production of high purity radiothallium

    DOEpatents

    Lebowitz, Elliot; Greene, Margaret W.

    1976-11-23

    The method of producing high purity thallium-201 for use as a myocardial scanning agent comprising the steps of irradiating a thallium target with protons to give the reaction .sup.203 Tl(p,3n) .sup.201.sub.Pb, separating in ion exchange columns the lead from the thallium isotopes, permitting the lead to decay, and then purifying the thallium solution and converting the thallium present to thallous form in which it can be used.

  10. Obtaining Highly Excited Eigenstates of Many-Body Localized Hamiltonians by the Density Matrix Renormalization Group Approach

    NASA Astrophysics Data System (ADS)

    Khemani, Vedika; Pollmann, Frank; Sondhi, S. L.

    2016-06-01

    The eigenstates of many-body localized (MBL) Hamiltonians exhibit low entanglement. We adapt the highly successful density-matrix renormalization group method, which is usually used to find modestly entangled ground states of local Hamiltonians, to find individual highly excited eigenstates of MBL Hamiltonians. The adaptation builds on the distinctive spatial structure of such eigenstates. We benchmark our method against the well-studied random field Heisenberg model in one dimension. At moderate to large disorder, the method successfully obtains excited eigenstates with high accuracy, thereby enabling a study of MBL systems at much larger system sizes than those accessible to exact-diagonalization methods.

  11. Obtaining Highly Excited Eigenstates of Many-Body Localized Hamiltonians by the Density Matrix Renormalization Group Approach.

    PubMed

    Khemani, Vedika; Pollmann, Frank; Sondhi, S L

    2016-06-17

    The eigenstates of many-body localized (MBL) Hamiltonians exhibit low entanglement. We adapt the highly successful density-matrix renormalization group method, which is usually used to find modestly entangled ground states of local Hamiltonians, to find individual highly excited eigenstates of MBL Hamiltonians. The adaptation builds on the distinctive spatial structure of such eigenstates. We benchmark our method against the well-studied random field Heisenberg model in one dimension. At moderate to large disorder, the method successfully obtains excited eigenstates with high accuracy, thereby enabling a study of MBL systems at much larger system sizes than those accessible to exact-diagonalization methods.

  12. Purity homophily in social networks.

    PubMed

    Dehghani, Morteza; Johnson, Kate; Hoover, Joe; Sagi, Eyal; Garten, Justin; Parmar, Niki Jitendra; Vaisey, Stephen; Iliev, Rumen; Graham, Jesse

    2016-03-01

    Does sharing moral values encourage people to connect and form communities? The importance of moral homophily (love of same) has been recognized by social scientists, but the types of moral similarities that drive this phenomenon are still unknown. Using both large-scale, observational social-media analyses and behavioral lab experiments, the authors investigated which types of moral similarities influence tie formations. Analysis of a corpus of over 700,000 tweets revealed that the distance between 2 people in a social-network can be predicted based on differences in the moral purity content-but not other moral content-of their messages. The authors replicated this finding by experimentally manipulating perceived moral difference (Study 2) and similarity (Study 3) in the lab and demonstrating that purity differences play a significant role in social distancing. These results indicate that social network processes reflect moral selection, and both online and offline differences in moral purity concerns are particularly predictive of social distance. This research is an attempt to study morality indirectly using an observational big-data study complemented with 2 confirmatory behavioral experiments carried out using traditional social-psychology methodology.

  13. Probing CP violation with time integrated decay rates into non-CP eigenstates

    NASA Astrophysics Data System (ADS)

    Silva, João P.

    1998-07-01

    Many of the experiments proposed to look for interference CP violation in neutral B mesons concentrate on tagged decay into CP eigenstates. Aleksan, Dunietz, Kayser and Le Diberder have shown that one can also look for interference CP violation using tagged decays into non-CP eigenstates. In all these methods, one must trace the time dependence of the decays. In this article we discuss a new method to search for interference CP violation by using only time integrated rates into non-CP eigenstates. The method hinges on the comparison between the decays of Υ(4S) into ff, f¯f¯, and ff¯, and also uses the rates for l+f and l-f. This method does not depend on how the Υ(4S) is produced; provided enough statistics, one can use both symmetric and asymmetric colliders.

  14. Classical ergodicity and quantum eigenstate thermalization: Analysis in fully connected Ising ferromagnets

    NASA Astrophysics Data System (ADS)

    Mori, Takashi

    2017-07-01

    We investigate the relation between the classical ergodicity and the quantum eigenstate thermalization in the fully connected Ising ferromagnets. In the case of spin-1/2, an expectation value of an observable in a single-energy eigenstate coincides with the long-time average in the underlying classical dynamics, which is a consequence of the Wentzel-Kramers-Brillouin approximation. In the case of spin-1, the underlying classical dynamics is not necessarily ergodic. In that case, it turns out that, in the thermodynamic limit, the statistics of the expectation values of an observable in the energy eigenstates coincides with the statistics of the long-time averages in the underlying classical dynamics starting from random initial states sampled uniformly from the classical phase space. This feature seems to be a general property in semiclassical systems, and the result presented here is crucial in discussing equilibration, thermalization, and dynamical transitions of such systems.

  15. A quantum algorithm for obtaining the energy spectrum of a physical system without guessing its eigenstates.

    PubMed

    Wang, Hefeng

    2014-08-14

    We present a quantum algorithm that provides a general approach for obtaining the energy spectrum of a physical system without making a guess on its eigenstates. In this algorithm, a probe qubit is coupled to a quantum register R which consists of one ancilla qubit and an n-qubit register that represents the system. R is prepared in a general reference state, and a general excitation operator that acts on R is constructed. The probe exhibits a dynamical response only when it is resonant with a transition from the reference state to an excited state of R which contains the eigenstates of the system. By varying the probe's frequency, the energy spectrum and the eigenstates of the system can be obtained.

  16. Trace map and eigenstates of a Thue-Morse chain in a general model

    NASA Astrophysics Data System (ADS)

    Cheng, Sheng-Feng; Jin, Guo-Jun

    2002-04-01

    By the standard method proposed by Kolar and Nori [Phys. Rev. B 42, 1062 (1990)], a rigorous eight-dimensional (8D) trace map for a general model of Thue-Morse (TM) sequences is obtained. Using this trace map, the characteristics of electronic eigenstates in TM lattices are explored in a very broad way. Simultaneously, a constraint condition for energy parameters, under which the complex 8D trace map can be simplified into the ordinary form, is found. It is also proved analytically that all eigenstates of TM lattices are extended when this constraint conditon is fulfilled. Furthermore, the properties of eigenstates beyond this constraint are investigated and some wave functions with critical features are discovered by the multifractal analysis. Our results support the previous viewpoint that a TM lattice is an intermediate stage between periodic and Fibonacci structures.

  17. Critical eigenstates and their properties in one- and two-dimensional quasicrystals

    NASA Astrophysics Data System (ADS)

    Macé, Nicolas; Jagannathan, Anuradha; Kalugin, Pavel; Mosseri, Rémy; Piéchon, Frédéric

    2017-07-01

    We present exact solutions for some eigenstates of hopping models on one- and two-dimensional quasiperiodic tilings and show that they are "critical" states, by explicitly computing their multifractal spectra. These eigenstates are shown to be generically present in 1D quasiperiodic chains, of which the Fibonacci chain is a special case. We then describe properties of the ground states for a class of tight-binding Hamiltonians on the 2D Penrose and Ammann-Beenker tilings. Exact and numerical solutions are seen to be in good agreement.

  18. Preparation of high purity copper fluoride by fluorinating copper hydroxyfluoride

    NASA Technical Reports Server (NTRS)

    King, R. B.; Lundquist, J. R.

    1969-01-01

    Copper fluoride containing no more than 50 ppm of any contaminating element was prepared by the fluorination of copper hydroxyfluoride. The impurity content was obtained by spark source mass spectrometry. High purity copper fluoride is needed as a cathode material for high energy density batteries.

  19. Finite size scaling for the many-body-localization transition: finite-size-pseudo-critical points of individual eigenstates

    NASA Astrophysics Data System (ADS)

    Monthus, Cécile

    2016-12-01

    To understand the finite-size-scaling properties of phases transitions in classical and quantum models in the presence of quenched disorder, it has proven to be fruitful to introduce the notion of a finite-size-pseudo-critical point in each disordered sample and to analyze its sample-to-sample fluctuations as a function of the size. For the many-body-localization transition, where very strong eigenstate-to-eigenstate fluctuations have been numerically reported even within a given disordered sample at a given energy density (Yu, Luitz and Clark 2016 arXiv:1606.01260 and Khemani, Lim, Sheng and Huse 2016 arXiv:1607.05756), it seems thus useful to introduce the notion of a finite-size-pseudo-critical point for each individual eigenstate and to study its eigenstate-to-eigenstate fluctuations governed by the correlation length exponent ν. The scaling properties of critical eigenstates are also expected to appear much more clearly if one considers each eigenstate at its finite-size-pseudo-critical point, where it is ‘truly critical’, while standard averages over eigenstates and samples in the critical region actually see a mixture of states that are effectively either localized or delocalized.

  20. Typical state of an isolated quantum system with fixed energy and unrestricted participation of eigenstates.

    PubMed

    Fine, Boris V

    2009-11-01

    This work describes the statistics for the occupation numbers of quantum levels in a large isolated quantum system, where all possible superpositions of eigenstates are allowed provided all these superpositions have the same fixed energy. Such a condition is not equivalent to the conventional microcanonical condition because the latter limits the participating eigenstates to a very narrow energy window. The statistics is obtained analytically for both the entire system and its small subsystem. In a significant departure from the Boltzmann-Gibbs statistics, the average occupation numbers of quantum states exhibit in the present case weak algebraic dependence on energy. In the macroscopic limit, this dependence is routinely accompanied by the condensation into the lowest-energy quantum state. This work contains initial numerical tests of the above statistics for finite systems and also reports the following numerical finding: when the basis states of large but finite random matrix Hamiltonians are expanded in terms of eigenstates, the participation of eigenstates in such an expansion obeys the newly obtained statistics. The above statistics might be observable in small quantum systems, but for the macroscopic systems, it rather re-enforces doubts about self-sufficiency of nonrelativistic quantum mechanics for justifying the Boltzmann-Gibbs equilibrium.

  1. General eigenstates of Maxwell's equations in a two-constituent composite medium

    NASA Astrophysics Data System (ADS)

    Bergman, David J.; Farhi, Asaf

    2016-11-01

    Eigenstates of Maxwell's equations in the quasistatic regime were used recently to calculate the response of a Veselago Lens1 to the field produced by a time dependent point electric charge.2, 3 More recently, this approach was extended to calculate the non-quasistatic response of such a lens. This necessitated a calculation of the eigenstates of the full Maxwell equations in a flat slab structure where the electric permittivity ɛ1 of the slab differs from the electric permittivity ɛ2 of its surroundings while the magnetic permeability is equal to 1 everywhere.4 These eigenstates were used to calculate the response of a Veselago Lens to an oscillating point electric dipole source of electromagnetic (EM) waves. A result of these calculations was that, although images with subwavelength resolution are achievable, as first predicted by John Pendry,5 those images appear not at the points predicted by geometric optics. They appear, instead, at points which lie upon the slab surfaces. This is strongly connected to the fact that when ɛ1/ɛ2 = -1 a strong singularity occurs in Maxwell's equations: This value of ɛ1/ɛ2 is a mathemetical accumulation point for the EM eigenvalues.6 Unfortunately, many physicists are unaware of this crucial mathematical property of Maxwell's equations. In this article we describe how the non-quasistatic eigenstates of Maxwell's equations in a composite microstructure can be calculated for general two-constituent microstructures, where both ɛ and μ have different values in the two constituents.

  2. Hydrogen adsorbed in a metal organic framework-5: coupled translation-rotation eigenstates from quantum five-dimensional calculations.

    PubMed

    Matanović, Ivana; Belof, Jonathan L; Space, Brian; Sillar, Kaido; Sauer, Joachim; Eckert, Juergen; Bačić, Zlatko

    2012-07-07

    We report rigorous quantum five-dimensional (5D) calculations of the coupled translation-rotation (T-R) eigenstates of a H(2) molecule adsorbed in metal organic framework-5 (MOF-5), a prototypical nanoporous material, which was treated as rigid. The anisotropic interactions between H(2) and MOF-5 were represented by the analytical 5D intermolecular potential energy surface (PES) used previously in the simulations of the thermodynamics of hydrogen sorption in this system [Belof et al., J. Phys. Chem. C 113, 9316 (2009)]. The global and local minima on this 5D PES correspond to all of the known binding sites of H(2) in MOF-5, three of which, α-, β-, and γ-sites are located on the inorganic cluster node of the framework, while two of them, the δ- and ε-sites, are on the phenylene link. In addition, 2D rotational PESs were calculated ab initio for each of these binding sites, keeping the center of mass of H(2) fixed at the respective equilibrium geometries; purely rotational energy levels of H(2) on these 2D PESs were computed by means of quantum 2D calculations. On the 5D PES, the three adjacent γ-sites lie just 1.1 meV above the minimum-energy α-site, and are separated from it by a very low barrier. These features allow extensive wave function delocalization of even the lowest translationally excited T-R eigenstates over the α- and γ-sites, presenting significant challenges for both the quantum bound-state calculations and the analysis of the results. Detailed comparison is made with the available experimental data.

  3. Hydrogen adsorbed in a metal organic framework-5: Coupled translation-rotation eigenstates from quantum five-dimensional calculations

    NASA Astrophysics Data System (ADS)

    Matanović, Ivana; Belof, Jonathan L.; Space, Brian; Sillar, Kaido; Sauer, Joachim; Eckert, Juergen; Bačić, Zlatko

    2012-07-01

    We report rigorous quantum five-dimensional (5D) calculations of the coupled translation-rotation (T-R) eigenstates of a H2 molecule adsorbed in metal organic framework-5 (MOF-5), a prototypical nanoporous material, which was treated as rigid. The anisotropic interactions between H2 and MOF-5 were represented by the analytical 5D intermolecular potential energy surface (PES) used previously in the simulations of the thermodynamics of hydrogen sorption in this system [Belof et al., J. Phys. Chem. C 113, 9316 (2009), 10.1021/jp901988e]. The global and local minima on this 5D PES correspond to all of the known binding sites of H2 in MOF-5, three of which, α-, β-, and γ-sites are located on the inorganic cluster node of the framework, while two of them, the δ- and ɛ-sites, are on the phenylene link. In addition, 2D rotational PESs were calculated ab initio for each of these binding sites, keeping the center of mass of H2 fixed at the respective equilibrium geometries; purely rotational energy levels of H2 on these 2D PESs were computed by means of quantum 2D calculations. On the 5D PES, the three adjacent γ-sites lie just 1.1 meV above the minimum-energy α-site, and are separated from it by a very low barrier. These features allow extensive wave function delocalization of even the lowest translationally excited T-R eigenstates over the α- and γ-sites, presenting significant challenges for both the quantum bound-state calculations and the analysis of the results. Detailed comparison is made with the available experimental data.

  4. Preparation of high purity phosphorus

    DOEpatents

    Rupp, Arthur F.; Woo, David V.

    1981-01-01

    High purity phosphorus and phosphorus compounds are prepared by first reacting H.sub.3 PO.sub.4 with a lead compound such as PbO to form Pb.sub.3 (PO.sub.4).sub.2. The Pb.sub.3 (PO.sub.4).sub.2 is reduced with H.sub.2 at a temperature sufficient to form gaseous phosphorus which can be recovered as a high purity phosphorus product. Phosphorus compounds can be easily prepared by reacting the phosphorus product with gaseous reactants. For example, the phosphorus product is reacted with gaseous Cl.sub.2 to form PCl.sub.5. PCl.sub.5 is reduced to PCl.sub.3 by contacting it in the gaseous phase with solid elemental phosphorus. POCl.sub.3 can be prepared by contacting PCl.sub.5 in the gaseous phase with solid P.sub.2 O.sub.5. The general process is particularly suitable for the preparation of radiophosphorus compounds.

  5. Iodine Absorption Cells Purity Testing

    PubMed Central

    Hrabina, Jan; Zucco, Massimo; Philippe, Charles; Pham, Tuan Minh; Holá, Miroslava; Acef, Ouali; Lazar, Josef; Číp, Ondřej

    2017-01-01

    This article deals with the evaluation of the chemical purity of iodine-filled absorption cells and the optical frequency references used for the frequency locking of laser standards. We summarize the recent trends and progress in absorption cell technology and we focus on methods for iodine cell purity testing. We compare two independent experimental systems based on the laser-induced fluorescence method, showing an improvement of measurement uncertainty by introducing a compensation system reducing unwanted influences. We show the advantages of this technique, which is relatively simple and does not require extensive hardware equipment. As an alternative to the traditionally used methods we propose an approach of hyperfine transitions’ spectral linewidth measurement. The key characteristic of this method is demonstrated on a set of testing iodine cells. The relationship between laser-induced fluorescence and transition linewidth methods will be presented as well as a summary of the advantages and disadvantages of the proposed technique (in comparison with traditional measurement approaches). PMID:28067834

  6. Accurate quantum calculations of translation-rotation eigenstates in electric-dipole-coupled H2O@C60 assemblies

    NASA Astrophysics Data System (ADS)

    Felker, Peter M.; Bačić, Zlatko

    2017-09-01

    We present methodology for variational calculation of the 6 n -dimensional translation-rotation (TR) eigenstates of assemblies of n H2O@C60 moieties coupled by dipole-dipole interactions. We show that the TR Hamiltonian matrix for any n can be constructed from dipole-dipole matrix elements computed for n = 2 . We present results for linear H2O@C60 assemblies. Two classes of eigenstates are revealed. One class comprises excitations of the 111 rotational level of H2O. The lowest-energy 111 -derived eigenstate for each assembly exhibits significant dipole ordering and shifts down in energy with the assembly size.

  7. Non-Local currents and the structure of eigenstates in planar discrete systems with local symmetries

    NASA Astrophysics Data System (ADS)

    Röntgen, M.; Morfonios, C. V.; Diakonos, F. K.; Schmelcher, P.

    2017-05-01

    Local symmetries are spatial symmetries present in a subdomain of a complex system. By using and extending a framework of so-called non-local currents that has been established recently, we show that one can gain knowledge about the structure of eigenstates in locally symmetric setups through a Kirchhoff-type law for the non-local currents. The framework is applicable to all discrete planar Schrödinger setups, including those with non-uniform connectivity. Conditions for spatially constant non-local currents are derived and we explore two types of locally symmetric subsystems in detail, closed-loops and one-dimensional open ended chains. We find these systems to support locally similar or even locally symmetric eigenstates.

  8. Controlling the duty cycle of the eigenstates in laser with multiple optical feedback.

    PubMed

    Zeng, Zhaoli; Zhang, Shulian; Tan, Yidong; Liu, Weixin

    2013-08-26

    The polarization dynamics of a quasi-isotropic single-mode laser subjected to multiple optical feedback is presented. The variable duty cycle of two eigenstates is observed in high-frequency optical fringes. The high-frequency optical fringes are induced by the multiple reflections in the asymmetry feedback cavity. The duty cycle of two eigenstates can be controlled easily by adjusting the position of polarization flipping due to the residual stress of laser mirror. Particularly, when the frequency difference results from residual stress is reduced to 1.5MHz, the position of polarization flipping moves to the edge of each fringe which can be used to measure small displacement with direction sensitivity and high resolution.

  9. Quantum nondemolition measurement of parity and generation of parity eigenstates in optical fields

    SciTech Connect

    Gerry, Christopher C.; Benmoussa, A.; Campos, R. A.

    2005-11-15

    The parity of photonic number states is known to be an important observable for quantized electromagnetic fields with applications to quantum information processing and to Heisenberg-limited measurement of phase shifts in quantum interferometry performed with maximally entangled states and with twin number states. In this paper we describe an approach to the quantum nondemolition measurement of parity for quantized optical fields. The method proposed involves the use of a cross-Kerr interaction where we assume a large Kerr nonlinearity is available through the techniques of electromagnetically induced transparency. Our proposed method does not require the measurement of photon number but rather measures parity directly. The method not only allows for the quantum nondemolition measurement of parity but also allows for the von Neumann projection of parity eigenstates from an arbitrary field state. The generation and detection of higher-order parity eigenstates is also discussed. Losses from dissipation and the effects of detector efficiency are considered.

  10. Measurement of CP-Violating Asymmetries in B0 Decays to CP Eigenstates

    NASA Astrophysics Data System (ADS)

    Aubert, B.; Boutigny, D.; de Bonis, I.; Gaillard, J.-M.; Jeremie, A.; Karyotakis, Y.; Lees, J. P.; Robbe, P.; Tisserand, V.; Palano, A.; Chen, G. P.; Chen, J. C.; Qi, N. D.; Rong, G.; Wang, P.; Zhu, Y. S.; Eigen, G.; Reinertsen, P. L.; Stugu, B.; Abbott, B.; Abrams, G. S.; Borgland, A. W.; Breon, A. B.; Brown, D. N.; Button-Shafer, J.; Cahn, R. N.; Clark, A. R.; Dardin, S.; Day, C.; Dow, S. F.; Elioff, T.; Fan, Q.; Gaponenko, I.; Gill, M. S.; Goozen, F. R.; Gowdy, S. J.; Gritsan, A.; Groysman, Y.; Jacobsen, R. G.; Jared, R. C.; Kadel, R. W.; Kadyk, J.; Karcher, A.; Kerth, L. T.; Kipnis, I.; Kluth, S.; Kolomensky, Yu. G.; Kral, J. F.; Lafever, R.; Leclerc, C.; Levi, M. E.; Lewis, S. A.; Lionberger, C.; Liu, T.; Long, M.; Lynch, G.; Marino, M.; Marks, K.; Meyer, A. B.; Mokhtarani, A.; Momayezi, M.; Nyman, M.; Oddone, P. J.; Ohnemus, J.; Oshatz, D.; Patton, S.; Perazzo, A.; Peters, C.; Pope, W.; Pripstein, M.; Quarrie, D. R.; Rasson, J. E.; Roe, N. A.; Romosan, A.; Ronan, M. T.; Shelkov, V. G.; Stone, R.; Telnov, A. V.; von der Lippe, H.; Weber, T.; Wenzel, W. A.; Zisman, M. S.; Bright-Thomas, P. G.; Harrison, T. J.; Hawkes, C. M.; Kirk, A.; Knowles, D. J.; O'Neale, S. W.; Watson, A. T.; Watson, N. K.; Deppermann, T.; Koch, H.; Krug, J.; Kunze, M.; Lewandowski, B.; Peters, K.; Schmuecker, H.; Steinke, M.; Andress, J. C.; Barlow, N. R.; Bhimji, W.; Chevalier, N.; Clark, P. J.; Cottingham, W. N.; de Groot, N.; Dyce, N.; Foster, B.; Mass, A.; McFall, J. D.; Wallom, D.; Wilson, F. F.; Abe, K.; Hearty, C.; Mattison, T. S.; McKenna, J. A.; Thiessen, D.; Camanzi, B.; Jolly, S.; McKemey, A. K.; Tinslay, J.; Blinov, V. E.; Bukin, A. D.; Bukin, D. A.; Buzykaev, A. R.; Dubrovin, M. S.; Golubev, V. B.; Ivanchenko, V. N.; Kolachev, G. M.; Korol, A. A.; Kravchenko, E. A.; Onuchin, A. P.; Salnikov, A. A.; Serednyakov, S. I.; Skovpen, Yu. I.; Telnov, V. I.; Yushkov, A. N.; Lankford, A. J.; Mandelkern, M.; McMahon, S.; Stoker, D. P.; Ahsan, A.; Buchanan, C.; Chun, S.; Macfarlane, D. B.; Prell, S.; Rahatlou, Sh.; Raven, G.; Sharma, V.; Burke, S.; Campagnari, C.; Dahmes, B.; Hale, D.; Hart, P. A.; Kuznetsova, N.; Kyre, S.; Levy, S. L.; Long, O.; Lu, A.; Richman, J. D.; Verkerke, W.; Witherell, M.; Yellin, S.; Beringer, J.; Dorfan, D. E.; Eisner, A. M.; Frey, A.; Grillo, A. A.; Grothe, M.; Heusch, C. A.; Johnson, R. P.; Kroeger, W.; Lockman, W. S.; Pulliam, T.; Sadrozinski, H.; Schalk, T.; Schmitz, R. E.; Schumm, B. A.; Seiden, A.; Spencer, E. N.; Turri, M.; Walkowiak, W.; Williams, D. C.; Chen, E.; Dubois-Felsmann, G. P.; Dvoretskii, A.; Hanson, J. E.; Hitlin, D. G.; Metzler, S.; Oyang, J.; Porter, F. C.; Ryd, A.; Samuel, A.; Weaver, M.; Yang, S.; Zhu, R. Y.; Devmal, S.; Geld, T. L.; Jayatilleke, S.; Jayatilleke, S. M.; Mancinelli, G.; Meadows, B. T.; Sokoloff, M. D.; Bloom, P.; Fahey, S.; Ford, W. T.; Gaede, F.; van Hoek, W. C.; Johnson, D. R.; Michael, A. K.; Nauenberg, U.; Olivas, A.; Park, H.; Rankin, P.; Roy, J.; Sen, S.; Smith, J. G.; Wagner, D. L.; Blouw, J.; Harton, J. L.; Krishnamurthy, M.; Soffer, A.; Toki, W. H.; Warner, D. W.; Wilson, R. J.; Zhang, J.; Brandt, T.; Brose, J.; Colberg, T.; Dahlinger, G.; Dickopp, M.; Dubitzky, R. S.; Eckstein, P.; Futterschneider, H.; Krause, R.; Maly, E.; Müller-Pfefferkorn, R.; Otto, S.; Schubert, K. R.; Schwierz, R.; Spaan, B.; Wilden, L.; Behr, L.; Bernard, D.; Bonneaud, G. R.; Brochard, F.; Cohen-Tanugi, J.; Ferrag, S.; Fouque, G.; Gastaldi, F.; Matricon, P.; Mora de Freitas, P.; Renard, C.; Roussot, E.; T'jampens, S.; Thiebaux, C.; Vasileiadis, G.; Verderi, M.; Anjomshoaa, A.; Bernet, R.; di Lodovico, F.; Khan, A.; Muheim, F.; Playfer, S.; Swain, J. E.; Falbo, M.; Bozzi, C.; Dittongo, S.; Folegani, M.; Piemontese, L.; Treadwell, E.; Anulli, F.; Baldini-Ferroli, R.; Calcaterra, A.; de Sangro, R.; Falciai, D.; Finocchiaro, G.; Patteri, P.; Peruzzi, I. M.; Piccolo, M.; Xie, Y.; Zallo, A.; Bagnasco, S.; Buzzo, A.; Contri, R.; Crosetti, G.; Lo Vetere, M.; Macri, M.; Monge, M. R.; Pallavicini, M.; Passaggio, S.; Pastore, F. C.; Patrignani, C.; Pia, M. G.; Robutti, E.; Santroni, A.; Morii, M.; Bartoldus, R.; Dignan, T.; Hamilton, R.; Mallik, U.; Cochran, J.; Crawley, H. B.; Fischer, P. A.; Lamsa, J.; McKay, R.; Meyer, W. T.; Rosenberg, E. I.; Albert, J. N.; Beigbeder, C.; Benkebil, M.; Breton, D.; Cizeron, R.; Du, S.; Grosdidier, G.; Hast, C.; Höcker, A.; Lepeltier, V.; Lutz, A. M.; Plaszczynski, S.; Schune, M. H.; Trincaz-Duvoid, S.; Truong, K.; Valassi, A.; Wormser, G.; Bionta, R. M.; Brigljević, V.; Brooks, A.; Fackler, O.; Fujino, D.; Lange, D. J.; Mugge, M.; O'Connor, T. G.; Pedrotti, B.; Shi, X.; van Bibber, K.; Wenaus, T. J.; Wright, D. M.; Wuest, C. R.; Yamamoto, B.; Carroll, M.; Fry, J. R.; Gabathuler, E.; Gamet, R.; George, M.; Kay, M.; Payne, D. J.; Sloane, R. J.; Touramanis, C.; Aspinwall, M. L.; Bowerman, D. A.; Dauncey, P. D.; Egede, U.; Eschrich, I.; Gunawardane, N. J.; Martin, R.; Nash, J. A.; Price, D. R.; Sanders, P.; Smith, D.; Azzopardi, D. E.; Back, J. J.; Dixon, P.; Harrison, P. F.; Newman-Coburn, D.; Potter, R. J.; Shorthouse, H. W.; Strother, P.; Vidal, P. B.; Williams, M. I.; Cowan, G.; George, S.; Green, M. G.; Kurup, A.; Marker, C. E.; McGrath, P.; McMahon, T. R.; Salvatore, F.; Scott, I.; Vaitsas, G.; Brown, D.; Davis, C. L.; Ford, K.; Li, Y.; Pavlovich, J.; Allison, J.; Barlow, R. J.; Boyd, J. T.; Fullwood, J.; Jackson, F.; Lafferty, G. D.; Savvas, N.; Simopoulos, E. T.; Thompson, R. J.; Weatherall, J. H.; Bard, R.; Farbin, A.; Jawahery, A.; Lillard, V.; Olsen, J.; Roberts, D. A.; Schieck, J. R.; Blaylock, G.; Dallapiccola, C.; Flood, K. T.; Hertzbach, S. S.; Kofler, R.; Lin, C. S.; Staengle, H.; Willocq, S.; Wittlin, J.; Brau, B.; Cowan, R.; Sciolla, G.; Taylor, F.; Yamamoto, R. K.; Britton, D. I.; Milek, M.; Patel, P. M.; Trischuk, J.; Lanni, F.; Palombo, F.; Bauer, J. M.; Booke, M.; Cremaldi, L.; Eschenberg, V.; Kroeger, R.; Reep, M.; Reidy, J.; Sanders, D. A.; Summers, D. J.; Beaulieu, M.; Martin, J. P.; Nief, J. Y.; Seitz, R.; Taras, P.; Zacek, V.; Nicholson, H.; Sutton, C. S.; Cavallo, N.; Cartaro, C.; de Nardo, G.; Fabozzi, F.; Gatto, C.; Lista, L.; Paolucci, P.; Piccolo, D.; Sciacca, C.; Losecco, J. M.; Alsmiller, J. R.; Gabriel, T. A.; Handler, T.; Heck, J.; Brau, J. E.; Frey, R.; Iwasaki, M.; Sinev, N. B.; Strom, D.; Borsato, E.; Colecchia, F.; dal Corso, F.; Galeazzi, F.; Margoni, M.; Marzolla, M.; Michelon, G.; Morandin, M.; Posocco, M.; Rotondo, M.; Simonetto, F.; Stroili, R.; Torassa, E.; Voci, C.; Bailly, P.; Benayoun, M.; Briand, H.; Chauveau, J.; David, P.; de La Vaissière, C.; del Buono, L.; Genat, J. F.; Hamon, O.; Le Diberder, F.; Lebbolo, H.; Leruste, Ph.; Lory, J.; Martin, L.; Roos, L.; Stark, J.; Versillé, S.; Zhang, B.; Manfredi, P. F.; Ratti, L.; Re, V.; Speziali, V.; Frank, E. D.; Gladney, L.; Guo, Q. H.; Panetta, J. H.; Angelini, C.; Batignani, G.; Bettarini, S.; Bondioli, M.; Bosi, F.; Carpinelli, M.; Forti, F.; Giorgi, M. A.; Lusiani, A.; Martinez-Vidal, F.; Morganti, M.; Neri, N.; Paoloni, E.; Rama, M.; Rizzo, G.; Sandrelli, F.; Simi, G.; Triggiani, G.; Walsh, J.; Haire, M.; Judd, D.; Paick, K.; Turnbull, L.; Wagoner, D. E.; Albert, J.; Bula, C.; Fernholz, R.; Lu, C.; McDonald, K. T.; Miftakov, V.; Sands, B.; Schaffner, S. F.; Smith, A. J.; Tumanov, A.; Varnes, E. W.; Bronzini, F.; Buccheri, A.; Bulfon, C.; Cavoto, G.; del Re, D.; Faccini, R.; Ferrarotto, F.; Ferroni, F.; Fratini, K.; Lamanna, E.; Leonardi, E.; Mazzoni, M. A.; Morganti, S.; Piredda, G.; Safai Tehrani, F.; Serra, M.; Voena, C.; Waldi, R.; Jacques, P. F.; Kalelkar, M.; Plano, R. J.; Adye, T.; Claxton, B.; Franek, B.; Galagedera, S.; Geddes, N. I.; Gopal, G. P.; Lidbury, J.; Xella, S. M.; Aleksan, R.; Besson, P.; Bourgeois, P.; de Domenico, G.; Emery, S.; Gaidot, A.; Ganzhur, S. F.; Gosset, L.; Hamel de Monchenault, G.; Kozanecki, W.; Langer, M.; London, G. W.; Mayer, B.; Serfass, B.; Vasseur, G.; Yeche, C.; Zito, M.; Copty, N.; Purohit, M. V.; Singh, H.; Yumiceva, F. X.; Adam, I.; Anthony, P. L.; Aston, D.; Baird, K.; Bartelt, J.; Becla, J.; Bell, R.; Bloom, E.; Boeheim, C. T.; Boyarski, A. M.; Boyce, R. F.; Bulos, F.; Burgess, W.; Byers, B.; Calderini, G.; Claus, R.; Convery, M. R.; Coombes, R.; Cottrell, L.; Coupal, D. P.; Coward, D. H.; Craddock, W. W.; Destaebler, H.; Dorfan, J.; Doser, M.; Dunwoodie, W.; Ecklund, S.; Fieguth, T. H.; Field, R. C.; Freytag, D. R.; Glanzman, T.; Godfrey, G. L.; Grosso, P.; Haller, G.; Hanushevsky, A.; Harris, J.; Hasan, A.; Hewett, J. L.; Himel, T.; Huffer, M. E.; Innes, W. R.; Jessop, C. P.; Kawahara, H.; Keller, L.; Kelsey, M. H.; Kim, P.; Klaisner, L. A.; Kocian, M. L.; Krebs, H. J.; Kunz, P. F.; Langenegger, U.; Langeveld, W.; Leith, D. W.; Louie, S. K.; Luitz, S.; Luth, V.; Lynch, H. L.; MacDonald, J.; Manzin, G.; Marsiske, H.; McCulloch, M.; McShurley, D.; Menke, S.; Messner, R.; Metcalfe, S.; Moffeit, K. C.; Mount, R.; Muller, D. R.; Nelson, D.; Nordby, M.; O'Grady, C. P.; O'Neill, F. G.; Oxoby, G.; Pavel, T.; Perl, J.; Petrak, S.; Putallaz, G.; Quinn, H.; Raines, P. E.; Ratcliff, B. N.; Reif, R.; Robertson, S. H.; Rochester, L. S.; Roodman, A.; Russell, J. J.; Sapozhnikov, L.; Saxton, O. H.; Schietinger, T.; Schindler, R. H.; Schwiening, J.; Seeman, J. T.; Serbo, V. V.; Skarpass, K.; Snyder, A.; Soha, A.; Spanier, S. M.; Stahl, A.; Stelzer, J.; Su, D.; Sullivan, M. K.; Talby, M.; Tanaka, H. A.; Va'Vra, J.; Wagner, S. R.; Weinstein, A. J.; White, J. L.; Wienands, U.; Wisniewski, W. J.; Young, C. C.; Zioulas, G.; Burchat, P. R.; Cheng, C. H.; Kirkby, D.; Meyer, T. I.; Roat, C.; de Silva, A.; Henderson, R.; Berridge, S.; Bugg, W.; Cohn, H.; Hart, E.; Weidemann, A. W.; Benninger, T.; Izen, J. M.; Kitayama, I.; Lou, X. C.; Turcotte, M.; Bianchi, F.; Bona, M.; di Girolamo, B.; Gamba, D.; Smol, A.; Zanin, D.; Bosisio, L.; della Ricca, G.; Lanceri, L.; Pompili, A.; Poropat, P.; Vuagnin, G.; Panvini, R. S.; Brown, C. M.; Kowalewski, R.; Roney, J. M.; Band, H. R.; Charles, E.; Dasu, S.; Elmer, P.; Hu, H.; Johnson, J. R.; Nielsen, J.; Orejudos, W.; Pan, Y.; Prepost, R.; Scott, I. J.; von Wimmersperg-Toeller, J. H.; Wu, S. L.; Yu, Z.; Zobernig, H.; Kordich, T. M.; Moore, T. B.; Neal, H.

    2001-03-01

    We present measurements of time-dependent CP-violating asymmetries in neutral B decays to several CP eigenstates. The measurement uses a data sample of 23×106 ϒ\\(4S\\)-->BB¯ decays collected by the BABAR detector at the PEP-II asymmetric B Factory at SLAC. In this sample, we find events in which one neutral B meson is fully reconstructed in a CP eigenstate containing charmonium and the flavor of the other neutral B meson is determined from its decay products. The amplitude of the CP-violating asymmetry, which in the standard model is proportional to sin2β, is derived from the decay time distributions in such events. The result is sin2β = 0.34+/-0.20 \\(stat\\)+/-0.05 \\(syst\\).

  11. Measurement of CP-violating asymmetries in B0 decays to CP eigenstates.

    PubMed

    Aubert, B; Boutigny, D; De Bonis, I; Gaillard, J M; Jeremie, A; Karyotakis, Y; Lees, J P; Robbe, P; Tisserand, V; Palano, A; Chen, G P; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Reinertsen, P L; Stugu, B; Abbott, B; Abrams, G S; Borgland, A W; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Clark, A R; Dardin, S; Day, C; Dow, S F; Elioff, T; Fan, Q; Gaponenko, I; Gill, M S; Goozen, F R; Gowdy, S J; Gritsan, A; Groysman, Y; Jacobsen, R G; Jared, R C; Kadel, R W; Kadyk, J; Karcher, A; Kerth, L T; Kipnis, I; Kluth, S; Kolomensky, Y G; Kral, J F; Lafever, R; LeClerc, C; Levi, M E; Lewis, S A; Lionberger, C; Liu, T; Long, M; Lynch, G; Marino, M; Marks, K; Meyer, A B; Mokhtarani, A; Momayezi, M; Nyman, M; Oddone, P J; Ohnemus, J; Oshatz, D; Patton, S; Perazzo, A; Peters, C; Pope, W; Pripstein, M; Quarrie, D R; Rasson, J E; Roe, N A; Romosan, A; Ronan, M T; Shelkov, V G; Stone, R; Telnov, A V; von der Lippe, H; Weber, T; Wenzel, W A; Zisman, M S; Bright-Thomas, P G; Harrison, T J; Hawkes, C M; Kirk, A; Knowles, D J; O'Neale, S W; Watson, A T; Watson, N K; Deppermann, T; Koch, H; Krug, J; Kunze, M; Lewandowski, B; Peters, K; Schmuecker, H; Steinke, M; Andress, J C; Barlow, N R; Bhimji, W; Chevalier, N; Clark, P J; Cottingham, W N; De Groot, N; Dyce, N; Foster, B; Mass, A; McFall, J D; Wallom, D; Wilson, F F; Abe, K; Hearty, C; Mattison, T S; McKenna, J A; Thiessen, D; Camanzi, B; Jolly, S; McKemey, A K; Tinslay, J; Blinov, V E; Bukin, A D; Bukin, D A; Buzykaev, A R; Dubrovin, M S; Golubev, V B; Ivanchenko, V N; Kolachev, G M; Korol, A A; Kravchenko, E A; Onuchin, A P; Salnikov, A A; Serednyakov, S I; Skovpen, Y I; Telnov, V I; Yushkov, A N; Lankford, A J; Mandelkern, M; McMahon, S; Stoker, D P; Ahsan, A; Buchanan, C; Chun, S; MacFarlane, D B; Prell, S; Rahatlou, S; Raven, G; Sharma, V; Burke, S; Campagnari, C; Dahmes, B; Hale, D; Hart, P A; Kuznetsova, N; Kyre, S; Levy, S L; Long, O; Lu, A; Richman, J D; Verkerke, W; Witherell, M; Yellin, S; Beringer, J; Dorfan, D E; Eisner, A M; Frey, A; Grillo, A A; Grothe, M; Heusch, C A; Johnson, R P; Kroeger, W; Lockman, W S; Pulliam, T; Sadrozinski, H; Schalk, T; Schmitz, R E; Schumm, B A; Seiden, A; Spencer, E N; Turri, M; Walkowiak, W; Williams, D C; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Hanson, J E; Hitlin, D G; Metzler, S; Oyang, J; Porter, F C; Ryd, A; Samuel, A; Weaver, M; Yang, S; Zhu, R Y; Devmal, S; Geld, T L; Jayatilleke, S; Jayatilleke, S M; Mancinelli, G; Meadows, B T; Sokoloff, M D; Bloom, P; Fahey, S; Ford, W T; Gaede, F; van Hoek, W C; Johnson, D R; Michael, A K; Nauenberg, U; Olivas, A; Park, H; Rankin, P; Roy, J; Sen, S; Smith, J G; Wagner, D L; Blouw, J; Harton, J L; Krishnamurthy, M; Soffer, A; Toki, W H; Warner, D W; Wilson, R J; Zhang, J; Brandt, T; Brose, J; Colberg, T; Dahlinger, G; Dickopp, M; Dubitzky, R S; Eckstein, P; Futterschneider, H; Krause, R; Maly, E; Müller-Pfefferkorn, R; Otto, S; Schubert, K R; Schwierz, R; Spaan, B; Wilden, L; Behr, L; Bernard, D; Bonneaud, G R; Brochard, F; Cohen-Tanugi, J; Ferrag, S; Fouque, G; Gastaldi, F; Matricon, P; Mora de Freitas, P; Renard, C; Roussot, E; T'Jampens, S; Thiebaux, C; Vasileiadis, G; Verderi, M; Anjomshoaa, A; Bernet, R; Di Lodovico, F; Khan, A; Muheim, F; Playfer, S; Swain, J E; Falbo, M; Bozzi, C; Dittongo, S; Folegani, M; Piemontese, L; Treadwell, E; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Falciai, D; Finocchiaro, G; Patteri, P; Peruzzi, I M; Piccolo, M; Xie, Y; Zallo, A; Bagnasco, S; Buzzo, A; Contri, R; Crosetti, G; Lo Vetere, M; Macri, M; Monge, M R; Pallavicini, M; Passaggio, S; Pastore, F C; Patrignani, C; Pia, M G; Robutti, E; Santroni, A; Morii, M; Bartoldus, R; Dignan, T; Hamilton, R; Mallik, U; Cochran, J; Crawley, H B; Fischer, P A; Lamsa, J; McKay, R; Meyer, W T; Rosenberg, E I; Albert, J N; Beigbeder, C; Benkebil, M; Breton, D; Cizeron, R; Du, S; Grosdidier, G; Hast, C; Höcker, A; LePeltier, V; Lutz, A M; Plaszczynski, S; Schune, M H; Trincaz-Duvoid, S; Truong, K; Valassi, A; Wormser, G; Bionta, R M; Brigljević, V; Brooks, A; Fackler, O; Fujino, D; Lange, D J; Mugge, M; O'Connor, T G; Pedrotti, B; Shi, X; van Bibber, K; Wenaus, T J; Wright, D M; Wuest, C R; Yamamoto, B; Carroll, M; Fry, J R; Gabathuler, E; Gamet, R; George, M; Kay, M; Payne, D J; Sloane, R J; Touramanis, C; Aspinwall, M L; Bowerman, D A; Dauncey, P D; Egede, U; Eschrich, I; Gunawardane, N J; Martin, R; Nash, J A; Price, D R; Sanders, P; Smith, D; Azzopardi, D E; Back, J J; Dixon, P; Harrison, P F; Newman-Coburn, D; Potter, R J; Shorthouse, H W; Strother, P; Vidal, P B; Williams, M I; Cowan, G; George, S; Green, M G; Kurup, A; Marker, C E; McGrath, P; McMahon, T R; Salvatore, F; Scott, I; Vaitsas, G; Brown, D; Davis, C L; Ford, K; Li, Y; Pavlovich, J; Allison, J; Barlow, R J; Boyd, J T; Fullwood, J; Jackson, F; Lafferty, G D; Savvas, N; Simopoulos, E T; Thompson, R J; Weatherall, J H; Bard, R; Farbin, A; Jawahery, A; Lillard, V; Olsen, J; Roberts, D A; Schieck, J R; Blaylock, G; Dallapiccola, C; Flood, K T; Hertzbach, S S; Kofler, R; Lin, C S; Staengle, H; Willocq, S; Wittlin, J; Brau, B; Cowan, R; Sciolla, G; Taylor, F; Yamamoto, R K; Britton, D I; Milek, M; Patel, P M; Trischuk, J; Lanni, F; Palombo, F; Bauer, J M; Booke, M; Cremaldi, L; Eschenberg, V; Kroeger, R; Reep, M; Reidy, J; Sanders, D A; Summers, D J; Beaulieu, M; Martin, J P; Nief, J Y; Seitz, R; Taras, P; Zacek, V; Nicholson, H; Sutton, C S; Cavallo, N; Cartaro, C; De Nardo, G; Fabozzi, F; Gatto, C; Lista, L; Paolucci, P; Piccolo, D; Sciacca, C; LoSecco, J M; Alsmiller, J R; Gabriel, T A; Handler, T; Heck, J; Brau, J E; Frey, R; Iwasaki, M; Sinev, N B; Strom, D; Borsato, E; Colecchia, F; Dal Corso, F; Galeazzi, F; Margoni, M; Marzolla, M; Michelon, G; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Torassa, E; Voci, C; Bailly, P; Benayoun, M; Briand, H; Chauveau, J; David, P; De La Vaissière, C; Del Buono, L; Genat, J F; Hamon, O; Le Diberder, F; Lebbolo, H; Leruste, P; Lory, J; Martin, L; Roos, L; Stark, J; Versillé, S; Zhang, B; Manfredi, P F; Ratti, L; Re, V; Speziali, V; Frank, E D; Gladney, L; Guo, Q H; Panetta, J H; Angelini, C; Batignani, G; Bettarini, S; Bondioli, M; Bosi, F; Carpinelli, M; Forti, F; Giorgi, M A; Lusiani, A; Martinez-Vidal, F; Morganti, M; Neri, N; Paoloni, E; Rama, M; Rizzo, G; Sandrelli, F; Simi, G; Triggiani, G; Walsh, J; Hairre, M; Judd, D; Paick, K; Turnbull, L; Wagoner, D E; Albert, J; Bula, C; Fernholz, R; Lu, C; McDonald, K T; Miftakov, V; Sands, B; Schaffner, S F; Smith, A J; Tumanov, A; Varnes, E W; Bronzini, F; Buccheri, A; Bulfon, C; Cavoto, G; del Re, D; Faccini, R; Ferrarotto, F; Ferroni, F; Fratini, K; Lamanna, E; Leonardi, E; Mazzoni, M A; Morganti, S; Piredda, G; Safai Tehrani, F; Serra, M; Voena, C; Waldi, R; Jacques, P F; Kalelkar, M; Plano, R J; Adye, T; Claxton, B; Franek, B; Galagedera, S; Geddes, N I; Gopal, G P; Lidbury, J; Xella, S M; Aleksan, R; Besson, P; Bourgeois, P; De Domenico, G; Emery, S; Gaidot, A; Ganzhur, S F; Gosset, L; Hamel de Monchenault, G; Kozanecki, W; Langer, M; London, G W; Mayer, B; Serfass, B; Vasseur, G; Yeche, C; Zito, M; Copty, N; Purohit, M V; Singh, H; Yumiceva, F X; Adam, I; Anthony, P L; Aston, D; Baird, K; Bartelt, J; Becla, J; Bell, R; Bloom, E; Boeheim, C T; Boyarski, A M; Boyce, R F; Bulos, F; Burgess, W; Byers, B; Calderini, G; Claus, R; Convery, M R; Coombes, R; Cottrell, L; Coupal, D P; Coward, D H; Craddock, W W; DeStaebler, H; Dorfan, J; Doser, M; Dunwoodie, W; Ecklund, S; Fieguth, T H; Field, R C; Freytag, D R; Glanzman, T; Godfrey, G L; Grosso, P; Haller, G; Hanushevsky, A; Harris, J; Hasan, A; Hewett, J L; Himel, T; Huffer, M E; Innes, W R; Jessop, C P; Kawahara, H; Keller, L; Kelsey, M H; Kim, P; Klaisner, L A; Kocian, M L; Krebs, H J; Kunz, P F; Langenegger, U; Langeveld, W; Leith, D W; Louie, S K; Luitz, S; Luth, V; Lynch, H L; MacDonald, J; Manzin, G; Mariske, H; McCulloch, M; McShurley, D; Menke, S; Messner, R; Metcalfe, S; Moffeit, K C; Mount, R; Muller, D R; Nelson, D; Nordby, M; O'Grady, C P; O'Neill, F G; Oxoby, G; Pavel, T; Perl, J; Petrak, S; Putallaz, G; Quinn, H; Raines, P E; Ratcliff, B N; Reif, R; Robertson, S H; Rochester, L S; Roodman, A; Russell, J J; Sapozhnikov, L; Saxton, O H; Schietinger, T; Schindler, R H; Schwiening, J; Seeman, J T; Serbo, V V; Skarpass, K; Snyder, A; Soha, A; Spanier, S M; Stahl, A; Stelzer, J; Su, D; Sullivan, M K; Talby, M; Tanaka, H A; Va'vra, J; Wagner, S R; Weinstein, A J; White, J L; Wienands, U; Wisniewski, W J; Young, C C; Zioulas, G; Burchat, P R; Cheng, C H; Kirkby, D; Meyer, T I; Roat, C; De Silva, A; Henderson, R; Berridge, S; Bugg, W; Cohn, H; Hart, E; Weidemann, A W; Benninger, T; Izen, J M; Kitayama, I; Lou, X C; Turcotte, M; Bianchi, F; Bona, M; Di Girolamo, B; Gamba, D; Smol, A; Zanin, D; Bosisio, L; Della Ricca, G; Lanceri, L; Pompili, A; Poropat, P; Vuagnin, G; Panvini, R S; Brown, C M; Kowalewski, R; Roney, J M; Band, H R; Charles, E; Dasu, S; Elmer, P; Hu, H; Johnson, J R; Nielsen, J; Orejudos, W; Pan, Y; Prepost, R; Scott, I J; von Wimmersperg-Toeller, J H; Wu, S L; Yu, Z; Zobernig, H; Kordich, T M; Moore, T B; Neal, H

    2001-03-19

    We present measurements of time-dependent CP-violating asymmetries in neutral B decays to several CP eigenstates. The measurement uses a data sample of 23x10(6) Upsilon(4S)-->BbarB decays collected by the BABAR detector at the PEP-II asymmetric B Factory at SLAC. In this sample, we find events in which one neutral B meson is fully reconstructed in a CP eigenstate containing charmonium and the flavor of the other neutral B meson is determined from its decay products. The amplitude of the CP-violating asymmetry, which in the standard model is proportional to sin2beta, is derived from the decay time distributions in such events. The result is sin2beta = 0.34+/-0.20 (stat)+/-0.05 (syst).

  12. Emergent eigenstate solution and emergent Gibbs ensemble for expansion dynamics in optical lattices

    NASA Astrophysics Data System (ADS)

    Vidmar, Lev; Xu, Wei; Rigol, Marcos

    2017-07-01

    Within the emergent eigenstate solution to quantum dynamics [Phys. Rev. X 7, 021012 (2017), 10.1103/PhysRevX.7.021012], one can construct a local operator (an emergent Hamiltonian) of which the time-evolving state is an eigenstate. Here we show that such a solution exists for the expansion dynamics of Tonks-Girardeau gases in optical lattices after turning off power-law (e.g., harmonic or quartic) confining potentials, which are geometric quenches that do not involve the boost operator. For systems that are initially in the ground state and undergo dynamical fermionization during the expansion, we show that they remain in the ground state of the emergent local Hamiltonian at all times. On the other hand, for systems at nonzero initial temperatures, the expansion dynamics can be described constructing a Gibbs ensemble for the emergent local Hamiltonian (an emergent Gibbs ensemble).

  13. Refinement trajectory and determination of eigenstates by a wavelet based adaptive method

    SciTech Connect

    Pipek, Janos; Nagy, Szilvia

    2006-11-07

    The detail structure of the wave function is analyzed at various refinement levels using the methods of wavelet analysis. The eigenvalue problem of a model system is solved in granular Hilbert spaces, and the trajectory of the eigenstates is traced in terms of the resolution. An adaptive method is developed for identifying the fine structure localization regions, where further refinement of the wave function is necessary.

  14. Bound eigenstate dynamics under a sudden shift of the well's wall

    SciTech Connect

    Granot, Er'el; Marchewka, Avi

    2010-03-15

    We investigate the dynamics of the eigenstate of an infinite well under an abrupt shift of the well's wall. It is shown that when the shift is small compared to the initial well's dimensions, the short-time behavior changes from the well-known t{sup 3/2} behavior to t{sup 1/2}. It is also shown that the complete dynamical picture converges to a universal function, which has fractal structure with dimensionality D=1.25.

  15. Broadband evolution of phononic-crystal-waveguide eigenstates in real- and k-spaces.

    PubMed

    Otsuka, P H; Nanri, K; Matsuda, O; Tomoda, M; Profunser, D M; Veres, I A; Danworaphong, S; Khelif, A; Benchabane, S; Laude, V; Wright, O B

    2013-11-27

    Control of sound in phononic band-gap structures promises novel control and guiding mechanisms. Designs in photonic systems were quickly matched in phononics, and rows of defects in phononic crystals were shown to guide sound waves effectively. The vast majority of work in such phononic guiding has been in the frequency domain, because of the importance of the phononic dispersion relation in governing acoustic confinement in waveguides. However, frequency-domain studies miss vital information concerning the phase of the acoustic field and eigenstate coupling. Using a wide range of wavevectors k, we implement an ultrafast technique to probe the wave field evolution in straight and L-shaped phononic crystal surface-phonon waveguides in real- and k-space in two spatial dimensions, thus revealing the eigenstate-energy redistribution processes and the coupling between different frequency-degenerate eigenstates. Such use of k-t space is a first in acoustics, and should have other interesting applications such as acoustic-metamaterial characterization.

  16. Pancharatnam-Berry optical element sorter of full angular momentum eigenstate.

    PubMed

    Walsh, Gary F

    2016-03-21

    We propose and numerically demonstrate a Pancharatnam-Berry optical element (PBOE) device that simultaneously sorts spin (SAM) and orbital (OAM) angular momentum. This device exploits the circular polarization selective properties of PBOEs to modulate independently the orthogonal SAM eigenstates within a geometric optical transformation that sorts OAM, enabling single measurement characterization of the full angular momentum eigenstate. This expands the available state space for OAM communication and enables characterization of the eigenmode composition of structured polarization beams. We define the two-dimensional orientation patterns of the transversely varying half-waveplate PBOEs that implement the angular momentum sorter. We show that the device discriminates the OAM and SAM eigenstates of optical beams including laser cavity modes such as Laguerre-Gaussian OAM eigenmodes, Hermite-Gaussian modes, and hybrid modes with complex structured polarization. We also demonstrate that it can determine the m parameter of higher order LGml Laguerre-Gaussian modes. The ability of this device to decode information from spatially structured optical phase has potential for applications in communication, encryption, modal characterization, and scientific measurements.

  17. Towards a heralded eigenstate-preserving measurement of multi-qubit parity in circuit QED

    NASA Astrophysics Data System (ADS)

    Huembeli, Patrick; Nigg, Simon E.

    2017-07-01

    Eigenstate-preserving multi-qubit parity measurements lie at the heart of stabilizer quantum error correction, which is a promising approach to mitigate the problem of decoherence in quantum computers. In this work we explore a high-fidelity, eigenstate-preserving parity readout for superconducting qubits dispersively coupled to a microwave resonator, where the parity bit is encoded in the amplitude of a coherent state of the resonator. Detecting photons emitted by the resonator via a current biased Josephson junction yields information about the parity bit. We analyze theoretically the measurement back action in the limit of a strongly coupled fast detector and show that in general such a parity measurement, while approximately quantum nondemolition is not eigenstate preserving. To remediate this shortcoming we propose a simple dynamical decoupling technique during photon detection, which greatly reduces decoherence within a given parity subspace. Furthermore, by applying a sequence of fast displacement operations interleaved with the dynamical decoupling pulses, the natural bias of this binary detector can be efficiently suppressed. Finally, we introduce the concept of a heralded parity measurement, where a detector click guarantees successful multi-qubit parity detection even for finite detection efficiency.

  18. Global characteristics of all eigenstates of local many-body Hamiltonians: participation ratio and entanglement entropy

    NASA Astrophysics Data System (ADS)

    Beugeling, W.; Andreanov, A.; Haque, Masudul

    2015-02-01

    In the spectrum of many-body quantum systems appearing in condensed matter physics, the low-energy eigenstates were the traditional focus of research. The interest in the statistical properties of the full eigenspectrum has grown more recently, in particular in the context of non-equilibrium questions. Wave functions of interacting lattice quantum systems can be characterized either by local observables or by global properties such as the participation ratio (PR) in a many-body basis or the entanglement between various partitions. We present a study of the PR and of the entanglement entropy (EE) between two roughly equal spatial partitions of the system, in all the eigenfunctions of local Hamiltonians. Motivated by the similarity of the PR and EE—both are generically larger in the bulk and smaller near the edges of the spectrum—we quantitatively analyze the correlation between them. We elucidate the effect of (proximity to) integrability, showing how low-entanglement and low-PR states appear also in the middle of the spectrum as one approaches integrable points. We also determine the precise scaling behaviour of the eigenstate-to-eigenstate fluctuations of the PR and EE with respect to system size and characterize the statistical distribution of these quantities near the middle of the spectrum.

  19. Characterizing eigenstate thermalization via measures in the Fock space of operators

    NASA Astrophysics Data System (ADS)

    Hosur, Pavan; Qi, Xiao-Liang

    2016-04-01

    The eigenstate thermalization hypothesis (ETH) attempts to bridge the gap between quantum mechanical and statistical mechanical descriptions of isolated quantum systems. Here, we define unbiased measures for how well the ETH works in various regimes, by mapping general interacting quantum systems on regular lattices onto a single particle living on a high-dimensional graph. By numerically analyzing deviations from ETH behavior in the nonintegrable Ising model, we propose a quantity that we call the n -weight to democratically characterize the average deviations for all operators residing on a given number of sites, irrespective of their spatial structure. It appears to have a simple scaling form, which we conjecture to hold true for all nonintegrable systems. A closely related quantity, which we term the n -distinguishability, tells us how well two states can be distinguished if only n -site operators are measured. Along the way, we discover that complicated operators on average are worse than simple ones at distinguishing between neighboring eigenstates, contrary to the naive intuition created by the usual statements of the ETH that few-body (many-body) operators acquire the same (different) expectation values in nearby eigenstates at finite energy density. Finally, we sketch heuristic arguments that the ETH originates from the limited ability of simple operators to distinguish between quantum states of a system, especially when the states are subject to constraints such as roughly fixed energy with respect to a local Hamiltonian.

  20. 21 CFR 610.13 - Purity.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 7 2013-04-01 2013-04-01 false Purity. 610.13 Section 610.13 Food and Drugs FOOD... BIOLOGICAL PRODUCTS STANDARDS General Provisions § 610.13 Purity. Products shall be free of extraneous... interpretation; standards to be met. The test for pyrogenic substances shall be performed according to the...

  1. 21 CFR 610.13 - Purity.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 7 2012-04-01 2012-04-01 false Purity. 610.13 Section 610.13 Food and Drugs FOOD... BIOLOGICAL PRODUCTS STANDARDS General Provisions § 610.13 Purity. Products shall be free of extraneous... interpretation; standards to be met. The test for pyrogenic substances shall be performed according to the...

  2. Purity analyses of high-purity organic compounds with nitroxyl radicals based on the Curie–Weiss law

    SciTech Connect

    Matsumoto, Nobuhiro Shimosaka, Takuya

    2015-05-07

    This work reports an attempt to quantify the purities of powders of high-purity organic compounds with stable nitroxyl radicals (namely, 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO), 1-oxyl-2,2,6,6-tetramethyl-4-hydroxypiperidine (TEMPOL), and 4-hydroxy-2,2,6,6-tetramethylpiperidine 1-oxyl benzoate (4-hydroxy-TEMPO benzoate)) in terms of mass fractions by using our “effective magnetic moment method,” which is based on both the Curie–Weiss law and a fundamental equation of electron paramagnetic resonance (ESR). The temperature dependence of the magnetic moment resulting from the radicals was measured with a superconducting quantum interference device magnetometer. The g value for each compound was measured with an X-band ESR spectrometer. The results of the purities were (0.998 ± 0.064) kg kg{sup −1} for TEMPO, (1.019 ± 0.040) kg kg{sup −1} for TEMPOL, and (1.001 ± 0.048) kg kg{sup −1} for 4-hydroxy-TEMPO benzoate. These results demonstrate that this analytical method as a future candidate of potential primary direct method can measure the purities with expanded uncertainties of approximately 5%.

  3. Proportion estimation using prior cluster purities

    NASA Technical Reports Server (NTRS)

    Terrell, G. R. (Principal Investigator)

    1980-01-01

    The prior distribution of CLASSY component purities is studied, and this information incorporated into maximum likelihood crop proportion estimators. The method is tested on Transition Year spring small grain segments.

  4. [Physiological analysis of a mathematical model for predicting somatic eigenstates under combined stresses].

    PubMed

    Yu, X J; Jia, S G; Chen, J S

    1999-06-01

    Objective. To put a mathematical model for predicting human somatic eigenstates (HS) into practical engineering design of countermeasures against combined stresses (hypoxia, heat, noise and vibration) in an aircraft cabin, and confirm the model from the human physiological viewpoint. Method. Published works on these 4 stresses were employed to verify the main and interactive effects which had been previously proved mathematically. Result. The main effects of 4 stresses and the significant interactive effects of 2 from 4 stresses agreed with the published experiments in single or in the same combination of these stresses. Conclusion. The model is reasonable in human physiological consideration and has been adopted in engineering design.

  5. Pushing the limits of the eigenstate thermalization hypothesis towards mesoscopic quantum systems.

    PubMed

    Steinigeweg, R; Khodja, A; Niemeyer, H; Gogolin, C; Gemmer, J

    2014-04-04

    In the ongoing discussion on thermalization in closed quantum many-body systems, the eigenstate thermalization hypothesis has recently been proposed as a universal concept and has attracted considerable attention. So far this concept is, as the name states, hypothetical. The majority of attempts to overcome this hypothetical character are based on exact diagonalization, which implies for, e.g., spin systems a limitation of roughly 15 spins. In this Letter we present an approach that pushes this limit up to system sizes of roughly 35 spins, thereby going significantly beyond what is possible with exact diagonalization. A concrete application to a Heisenberg spin ladder which yields conclusive results is demonstrated.

  6. High-energy localized eigenstates of an electronic resonator in a magnetic field

    NASA Astrophysics Data System (ADS)

    Zalipaev, V. V.; Kusmartsev, F. V.; Popov, M. M.

    2008-02-01

    We present a semiclassical analysis of the high-energy eigenstates of an electron inside a closed resonator. An asymptotic method of the construction of the energy spectrum and eigenfunctions, localized in the small neighborhood of a periodic orbit, is developed in the presence of a homogeneous magnetic field and arbitrary scalar potential. The isolated periodic orbit is confined between two interfaces which could be planar, concave or even convex. Such a system represents a quantum electronic resonator, an analog of the well-known high-frequency optical or acoustic resonator with eigenmodes called 'bouncing ball vibrations'. The first step in the asymptotic analysis involves constructing a solitary localized asymptotic solution to the Schrödinger equation (electronic Gaussian beam—wavepackage). Then, the stability of a closed continuous family of periodic trajectories confined between two reflecting surfaces of the resonator boundary was studied. The asymptotics of the eigenfunctions were constructed as a superposition of two electronic Gaussian beams propagating in opposite directions between two reflecting points of the periodic orbits. The asymptotics of the energy spectrum are obtained by the generalized Bohr-Sommerfeld quantization condition derived as a requirement for the eigenfunction asymptotics to be periodic. For one class of periodic orbits, localized eigenstates were computed numerically by the finite element method using FEMLAB and proved to be in a very good agreement with those computed semiclassically.

  7. Vibronic eigenstates and the geometric phase effect in the (2)E″ state of NO3.

    PubMed

    Eisfeld, Wolfgang; Viel, Alexandra

    2017-01-21

    The (2)E″ state of NO3, a prototype for the Jahn-Teller effect, has been an enigma and a challenge for a long time for both experiment and theory. We present a detailed theoretical study of the vibronic quantum dynamics in this electronic state, uncovering the effects of tunnelling, geometric phase, and symmetry. To this end, 45 vibronic levels of NO3 in the (2)E″ state are determined accurately and analyzed thoroughly. The computation is based on a high quality diabatic potential representation of the two-sheeted surface of the (2)E″ state developed by us [W. Eisfeld et al., J. Chem. Phys. 140, 224109 (2014)] and on the multi-configuration time dependent Hartree approach. The vibrational eigenstates of the NO3(-) anion are determined and analyzed as well to gain a deeper understanding of the symmetry properties of such D3h symmetric systems. To this end, 61 eigenstates of the NO3(-) anion ground state are computed using the single sheeted potential surface of the (1)A1 state published in the same reference quoted above. The assignments of both the vibrational and vibronic levels are discussed. A simple model is proposed to rationalize the computed NO3 spectrum strongly influenced by the Jahn-Teller couplings, the associated geometric phase effect, and the tunnelling. Comparison with the available spectroscopic data is also presented.

  8. Vibronic eigenstates and the geometric phase effect in the 2E″ state of NO3

    NASA Astrophysics Data System (ADS)

    Eisfeld, Wolfgang; Viel, Alexandra

    2017-01-01

    The 2E″ state of NO3, a prototype for the Jahn-Teller effect, has been an enigma and a challenge for a long time for both experiment and theory. We present a detailed theoretical study of the vibronic quantum dynamics in this electronic state, uncovering the effects of tunnelling, geometric phase, and symmetry. To this end, 45 vibronic levels of NO3 in the 2E″ state are determined accurately and analyzed thoroughly. The computation is based on a high quality diabatic potential representation of the two-sheeted surface of the 2E″ state developed by us [W. Eisfeld et al., J. Chem. Phys. 140, 224109 (2014)] and on the multi-configuration time dependent Hartree approach. The vibrational eigenstates of the NO3- anion are determined and analyzed as well to gain a deeper understanding of the symmetry properties of such D3h symmetric systems. To this end, 61 eigenstates of the NO3- anion ground state are computed using the single sheeted potential surface of the 1A1 state published in the same reference quoted above. The assignments of both the vibrational and vibronic levels are discussed. A simple model is proposed to rationalize the computed NO3 spectrum strongly influenced by the Jahn-Teller couplings, the associated geometric phase effect, and the tunnelling. Comparison with the available spectroscopic data is also presented.

  9. Spectroscopic Determination of Trace Contaminants in High Purity Oxygen

    NASA Technical Reports Server (NTRS)

    Hornung, Steven D.

    2011-01-01

    Oxygen used for extravehicular activities (EVA) must be free of contaminants because a difference in a few tenths of a percent of argon or nitrogen content can mean significant reduction in available EVA time. These inert gases build up in the extravehicular mobility unit because they are not metabolized or scrubbed from the atmosphere. Measurement of oxygen purity above 99.5% is problematic, and currently only complex instruments such as gas chromatographs or mass spectrometers are used for these determinations. Because liquid oxygen boil-off from the space shuttle will no longer be available to supply oxygen for EVA use, other concepts are being developed to produce and validate high purity oxygen from cabin air aboard the International Space Station. A prototype optical emission technique capable of detecting argon and nitrogen below 0.1% in oxygen was developed at White Sands Test Facility. This instrument uses a glow discharge in reduced pressure gas to produce atomic emission from the species present. Because the atomic emission lines from oxygen, nitrogen, and argon are discrete and in many cases well-separated, trace amounts of argon and nitrogen can be detected in the ultraviolet and visible spectrum. This is a straightforward, direct measurement of the target contaminants and may lend itself to a device capable of on-orbit verification of oxygen purity. System design and optimized measurement parameters are presented.

  10. High purity silane and silicon production

    NASA Technical Reports Server (NTRS)

    Breneman, William C. (Inventor)

    1987-01-01

    Silicon tetrachloride, hydrogen and metallurgical silicon are reacted at about 400.degree.-600.degree. C. and at pressures in excess of 100 psi, and specifically from about 300 up to about 600 psi to form di- and trichlorosilane that is subjected to disproportionation in the presence of an anion exchange resin to form high purity silane. By-product and unreacted materials are recycled, with metallurgical silicon and hydrogen being essentially the only consumed feed materials. The silane product may be further purified, as by means of activated carbon or cryogenic distillation, and decomposed in a fluid bed or free space reactor to form high purity polycrystalline silicon and by-product hydrogen which can be recycled for further use. The process results in simplified waste disposal operations and enhances the overall conversion of metallurgical grade silicon to silane and high purity silicon for solar cell and semiconductor silicon applications.

  11. High purity silica reflective heat shield development

    NASA Technical Reports Server (NTRS)

    Blome, J.

    1974-01-01

    Progress is reported on the development of a high purity reflective heat shield material. Silicon dioxide was selected as the material because it is highly reflective in the correct wavelength band, has good ablation characteristics, is thermal shock resistant, and is readily fabricated to full size at reasonable cost. Conclusions indicate that: reflectance is affected by purity and morphology; the pure material is readily available; required purity and morphology can be maintained with reasonable care; high reflectances are determined (0.99 from 0.4 to 1.2 microns); major processing steps are defined; and the material appears to be cost effective. It is indicated that the materials are developed to the point of readiness for full scale fabrication and characterization.

  12. Signatures of classical structures in the leading eigenstates of quantum dissipative systems

    NASA Astrophysics Data System (ADS)

    Carlo, Gabriel G.; Ermann, Leonardo; Rivas, Alejandro M. F.; Spina, María E.

    2017-09-01

    By analyzing a paradigmatic example of the theory of dissipative systems—the classical and quantum dissipative standard map—we are able to explain the main features of the decay to the quantum equilibrium state. The classical isoperiodic stable structures typically present in the parameter space of these kinds of systems play a fundamental role. In fact, we have found that the period of stable structures that are near in this space determines the phase of the leading eigenstates of the corresponding quantum superoperator. Moreover, the eigenvectors show a strong localization on the corresponding periodic orbits (limit cycles). We show that this sort of scarring phenomenon (an established property of Hamiltonian and projectively open systems) is present in the dissipative case and it is of extreme simplicity.

  13. Spin eigen-states of Dirac equation for quasi-two-dimensional electrons

    SciTech Connect

    Eremko, Alexander; Brizhik, Larissa; Loktev, Vadim

    2015-10-15

    Dirac equation for electrons in a potential created by quantum well is solved and the three sets of the eigen-functions are obtained. In each set the wavefunction is at the same time the eigen-function of one of the three spin operators, which do not commute with each other, but do commute with the Dirac Hamiltonian. This means that the eigen-functions of Dirac equation describe three independent spin eigen-states. The energy spectrum of electrons confined by the rectangular quantum well is calculated for each of these spin states at the values of energies relevant for solid state physics. It is shown that the standard Rashba spin splitting takes place in one of such states only. In another one, 2D electron subbands remain spin degenerate, and for the third one the spin splitting is anisotropic for different directions of 2D wave vector.

  14. Origami rules for the construction of localized eigenstates of the Hubbard model in decorated lattices

    NASA Astrophysics Data System (ADS)

    Dias, R. G.; Gouveia, J. D.

    2015-11-01

    We present a method of construction of exact localized many-body eigenstates of the Hubbard model in decorated lattices, both for U = 0 and U → ∞. These states are localized in what concerns both hole and particle movement. The starting point of the method is the construction of a plaquette or a set of plaquettes with a higher symmetry than that of the whole lattice. Using a simple set of rules, the tight-binding localized state in such a plaquette can be divided, folded and unfolded to new plaquette geometries. This set of rules is also valid for the construction of a localized state for one hole in the U → ∞ limit of the same plaquette, assuming a spin configuration which is a uniform linear combination of all possible permutations of the set of spins in the plaquette.

  15. Origami rules for the construction of localized eigenstates of the Hubbard model in decorated lattices

    PubMed Central

    Dias, R. G.; Gouveia, J. D.

    2015-01-01

    We present a method of construction of exact localized many-body eigenstates of the Hubbard model in decorated lattices, both for U = 0 and U → ∞. These states are localized in what concerns both hole and particle movement. The starting point of the method is the construction of a plaquette or a set of plaquettes with a higher symmetry than that of the whole lattice. Using a simple set of rules, the tight-binding localized state in such a plaquette can be divided, folded and unfolded to new plaquette geometries. This set of rules is also valid for the construction of a localized state for one hole in the U → ∞ limit of the same plaquette, assuming a spin configuration which is a uniform linear combination of all possible permutations of the set of spins in the plaquette. PMID:26581296

  16. Beam dynamics in disordered P T -symmetric optical lattices based on eigenstate analyses

    NASA Astrophysics Data System (ADS)

    Yao, Xiankun; Liu, Xueming

    2017-03-01

    Wave functions will experience a localization process when evolving in disordered lattices. Here, we have demonstrated the effects of disordered P T -symmetric potentials on wave-function characteristics in optics based on eigenstate analyses. In weak-disorder cases, by using the tight-binding approximation method, a conclusion is obtained that the increasing of the imaginary part of potential can enhance the diffraction, while the increasing disorder will block the diffraction and lead to localization. In the general case, band theory is used for band-structure analysis of three bands. We find that the disorder has a smaller effect on the higher-order band, which is proved by the beam evolutions. Our work may be instructive for realizing beam path control by manipulating the strengths of disorder and gain and/or loss of lattice.

  17. Quasi adiabatic dynamics of energy eigenstates for a solvable quantum system at finite temperature

    NASA Astrophysics Data System (ADS)

    Monnai, Takaaki

    2017-09-01

    It is a fundamental problem to characterize nonequilibrium processes. For a moving one-dimensional potential, we explore the nonequilibrium dynamics of the initial energy eigenstates for a confined quantum system interacting with a large reservoir. For concreteness, we investigate a dragged harmonic oscillator linearly interacting with an assembly of harmonic oscillators, and explore the deviation from adiabatic processes by rigorously calculating the so-called persistent amplitude. In particular, we show that the phase of the persistent amplitude is considered to be common both for the ground and excited states. Also, we can define the quasi adiabatic processes in a well-defined double limit of small perturbation and a sufficiently long time in terms of the phase and absolute value of the persistent amplitude.

  18. Mathematics of small stochastic reaction networks: A boundary layer theory for eigenstate analysis

    PubMed Central

    Mjolsness, Eric; Prasad, Upendra

    2013-01-01

    We study and analyze the stochastic dynamics of a reversible bimolecular reaction A + B ↔ C called the “trivalent reaction.” This reaction is of a fundamental nature and is part of many biochemical reaction networks. The stochastic dynamics is given by the stochastic master equation, which is difficult to solve except when the equilibrium state solution is desired. We present a novel way of finding the eigenstates of this system of difference-differential equations, using perturbation analysis of ordinary differential equations arising from approximation of the difference equations. The time evolution of the state probabilities can then be expressed in terms of the eigenvalues and the eigenvectors. PMID:23514469

  19. HPLC direct purity assay using ultra-purified materials as primary standards.

    PubMed

    Le Goff, Thierry; Champarnaud, Elodie; Fardus, Fahmina

    2010-12-01

    Reference materials certified for purity are essential to ensure harmonization of analytical measurements. LGC is currently certifying these materials using an indirect multi-method approach quantifying impurities: Related substances using high-performance liquid chromatography, gas chromatography (GC), differential scanning calorimetry; Residual solvents using headspace GC coupled to mass spectrometry; Inorganic content using ashing, acid digest ion couple plasma mass spectrometry or thermogravimetric analysis; Water using oven coulometric Karl Fischer/direct addition coulometric Karl Fischer. Related substances are not straightforward to quantify without an appropriate standard due to possible difference in response factor for the impurity relative to the main compound. In this article, existing LGC RMs certified for purity were purified further using semi-preparative HPLC. These ultra-purified organic substances were virtually free of related substances making their purity assessment faster and more straightforward, i.e., no need to identify impurities and subsequently quantify them. After characterization, these ultra-purified standards were used as calibrants to determine directly the mass fraction of the analyte in the original CRM using exact matching single-point HPLC calibration. This new approach opens the possibility of certifying the purity of low purity substances with a relative small uncertainty without the need of identifying the impurities present in the sample.

  20. Microscopic Evaluation of Contaminants in Ultra-High Purity Copper

    SciTech Connect

    Hoppe, Eric W.; Mintzer, Esther E.; Aalseth, Craig E.; Edwards, Danny J.; Farmer, Orville T.; Fast, James E.; Gerlach, David C.; Liezers, Martin; Miley, Harry S.

    2009-10-08

    Copper is one of the very few elements having no relatively long-lived radioisotopes and which can be electrodeposited to ultra-high levels of purity. Next generation experiments probing neutrino properties and searching for direct evidence of Dark Matter require ultra-clean materials, such as copper, containing the smallest quantities obtainable of naturally occurring radioactive contaminants. Copper is also of interest in the material science field for applications requiring low-activity materials, such as in electronics and semi-conductors, an example of which is reduced alpha activity, low-fault integrated circuits. Determining the purity of the copper is of great interest, but even more important is establishing the location of any contamination and its dispersion within the bulk material. Co-deposition of contaminants during copper electrodeposition and its relationship to nucleation and growth processes were investigated using a variety of analytical methods including scanning electron microscopy (SEM), laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), and secondary ionization mass spectrometry (SIMS).

  1. Modified matrix volatilization setup for characterization of high purity germanium.

    PubMed

    Meruva, Adisesha Reddy; Raparthi, Shekhar; Kumar, Sunil Jai

    2016-01-01

    Modified matrix volatilization (MV) method has been described to characterize high purity germanium material of 7 N (99.99999%) purity. Transport of both, the chlorine gas generated in-situ in this method and the argon gas (carrier) is fine controlled by means of a mass flow controller. This enabled both uniform reaction of chlorine gas with the germanium matrix and smooth removal of germanium matrix as its chloride. This resulted in improvement in the reproducibility of the analytical results. The use of quartz reaction vessel has lead to the reduction in the process blank levels. The combined effect of these modifications in the MV setup has resulted in very consistent and low process blanks and hence improved detection limits of this method. Applicability of the method has been expanded to rare earth elements and other elements after examining their recoveries. The quantification is done by using inductively coupled plasma quadrupole mass spectrometer (ICP-QMS) and continuum source graphite furnace atomic absorption spectrometry (CS-GFAAS). In the absence of certified reference materials for high pure germanium, the accuracy of the method is established by spike recovery tests. The precision of the method has been found to vary from 1 to 30% for concentrations between 1 and 30 ng g(-1). The limits of detection (LOD) for the target analytes are found to be between 18 and 0.033 ng g(-1). Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Importance of Purity Evaluation and the Potential of Quantitative 1H NMR as a Purity Assay

    PubMed Central

    2015-01-01

    In any biomedical and chemical context, a truthful description of chemical constitution requires coverage of both structure and purity. This qualification affects all drug molecules, regardless of development stage (early discovery to approved drug) and source (natural product or synthetic). Purity assessment is particularly critical in discovery programs and whenever chemistry is linked with biological and/or therapeutic outcome. Compared with chromatography and elemental analysis, quantitative NMR (qNMR) uses nearly universal detection and provides a versatile and orthogonal means of purity evaluation. Absolute qNMR with flexible calibration captures analytes that frequently escape detection (water, sorbents). Widely accepted structural NMR workflows require minimal or no adjustments to become practical 1H qNMR (qHNMR) procedures with simultaneous qualitative and (absolute) quantitative capability. This study reviews underlying concepts, provides a framework for standard qHNMR purity assays, and shows how adequate accuracy and precision are achieved for the intended use of the material. PMID:25295852

  3. High purity silica reflecting heat shield development

    NASA Technical Reports Server (NTRS)

    Congdon, W.

    1974-01-01

    A reflecting heat shield composed of fused silica in which the scattering results from the refractive index mismatch between silica particles and the voids introduced during the fabrication process is developed. Major considerations and conclusions of the development are: the best material to use is Type A, which is capable of ultra-high-purity and which does not show the 0.243 micrometer absorption band; the reflection efficiency of fused silica is decreased at higher temperatures due to the bathochromic shift of the ultraviolet cut-off; for a given silica material, over the wavelength region and particle sizes tested, the monodisperse particle size configurations produce higher reflectances than continuous particle size configurations; and the smaller monodisperse particle size configurations give higher reflectance than the larger ones. A reflecting silica configuration that is an efficient reflector of shock layer radiation at high ablation temperatures is achieved by tailoring the matrix for optimum scattering and using an ultra-high-purity material.

  4. High purity silica reflective heat shield development

    NASA Technical Reports Server (NTRS)

    Nachtscheim, P. R.; Blome, J. C.

    1976-01-01

    A hyperpure vitreous silica material is being developed for use as a reflective and ablative heat shield for planetary entry. Various purity grades and forms of raw materials were evaluated along with various processing methods. Slip casting of high purity grain was selected as the best processing method, resulting in a highly reflective material in the wavelength bands of interest (the visible and ultraviolet regions). The selected material was characterized with respect to optical, mechanical and physical properties using a limited number of specimens. The process has been scaled up to produce a one-half scale heat shield (18 in. dia.) (45.72 cm) for a Jupiter entry vehicle. This work is now being extended to improve the structural safety factor of the heat shield by making hyperpure silica material tougher through the addition of silica fibers.

  5. Isospin purity in the A=42 isobars

    SciTech Connect

    Orce, J.N.; McKay, C.J.; Choudry, S.N.; Lesher, S.L.; Mynk, M.; Bandyopadhyay, D.; Yates, S.W.; McEllistrem, M.T.; Petkov, P.

    2004-09-13

    The lifetime of the first 2{sub T=1}{sup +} state in 42Sc has been measured as 74(16) fs. This result gives a value for the isoscalar matrix element of M0=6.63(76). From the mirror nuclei, 42Ca and 42Ti, the isoscalar matrix element is given as 7.15(48) W.u., confirming isospin purity in the A=42 isobars.

  6. 7 CFR 201.60 - Purity percentages.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... (2) mixtures in which the particle-weight ratio is 1:1 to 1.49:1, inclusive. Tolerances for... Component of a Purity Analysis for (1) Unmixed Seed or (2) Mixed Seed in Which the Particle Weight Ratio Is... particle-weight ratio is 1.5:1 to 20:1 and beyond: The symbols used in the formula are as follows: T...

  7. Purity of targets prepared on Cu substrates

    NASA Astrophysics Data System (ADS)

    Méens, A.; Rossini, I.; Sens, J. C.

    1993-09-01

    The purity of several elemental self-supporting targets usually prepared by evaporation onto soluble Cu substrates has been studied. The targets were analysed by Rutherford backscattering and instrumental neutron activation analysis. Because of the high percentage of Cu observed in some Si targets, further measurements, including transmission electron microscopy, have been performed on Si targets deposited by e-gun bombardment onto Cu and ion-beam sputtering onto betaine.

  8. Chemometric quality control of chromatographic purity.

    PubMed

    Laursen, Kristoffer; Frederiksen, Søren Søndergaard; Leuenhagen, Casper; Bro, Rasmus

    2010-10-15

    It is common practice in chromatographic purity analysis of pharmaceutical manufacturing processes to assess the quality of peak integration combined by visual investigation of the chromatogram. This traditional method of visual chromatographic comparison is simple, but is very subjective, laborious and seldom very quantitative. For high-purity drugs it would be particularly difficult to detect the occurrence of an unknown impurity co-eluting with the target compound, which is present in excess compared to any impurity. We hypothesize that this can be achieved through Multivariate Statistical Process Control (MSPC) based on principal component analysis (PCA) modeling. In order to obtain the lowest detection limit, different chromatographic data preprocessing methods such as time alignment, baseline correction and scaling are applied. Historical high performance liquid chromatography (HPLC) chromatograms from a biopharmaceutical in-process analysis are used to build a normal operation condition (NOC) PCA model. Chromatograms added simulated 0.1% impurities with varied resolutions are exposed to the NOC model and monitored with MSPC charts. This study demonstrates that MSPC based on PCA applied on chromatographic purity analysis is a powerful tool for monitoring subtle changes in the chromatographic pattern, providing clear diagnostics of subtly deviating chromatograms. The procedure described in this study can be implemented and operated as the HPLC analysis runs according to the process analytical technology (PAT) concept aiming for real-time release. Copyright © 2010 Elsevier B.V. All rights reserved.

  9. Method of high purity silane preparation

    DOEpatents

    Tsuo, Y. Simon; Belov, Eugene P.; Gerlivanov, Vadim G.; Zadde, Vitali V.; Kleschevnikova, Solomonida I.; Korneev, Nikolai N.; Lebedev, Eugene N.; Pinov, Akhsarbek B.; Ryabenko, Eugene A.; Strebkov, Dmitry S.; Chernyshev, Eugene A.

    2000-01-01

    A process for the preparation of high purity silane, suitable for forming thin layer silicon structures in various semiconductor devices and high purity poly- and single crystal silicon for a variety of applications, is provided. Synthesis of high-purity silane starts with a temperature assisted reaction of metallurgical silicon with alcohol in the presence of a catalyst. Alcoxysilanes formed in the silicon-alcohol reaction are separated from other products and purified. Simultaneous reduction and oxidation of alcoxysilanes produces gaseous silane and liquid secondary products, including, active part of a catalyst, tetra-alcoxysilanes, and impurity compounds having silicon-hydrogen bonds. Silane is purified by an impurity adsorption technique. Unreacted alcohol is extracted and returned to the reaction with silicon. Concentrated mixture of alcoxysilanes undergoes simultaneous oxidation and reduction in the presence of a catalyst at the temperature -20.degree. C. to +40.degree. C. during 1 to 50 hours. Tetra-alcoxysilane extracted from liquid products of simultaneous oxidation and reduction reaction is directed to a complete hydrolysis. Complete hydrolysis of tetra-alcoxysilane results in formation of industrial silica sol and alcohol. Alcohol is dehydrated by tetra-alcoxysilane and returned to the reaction with silicon.

  10. High-purity germanium crystal growing

    SciTech Connect

    Hansen, W.L.; Haller, E.E.

    1982-10-01

    The germanium crystals used for the fabrication of nuclear radiation detectors are required to have a purity and crystalline perfection which is unsurpassed by any other solid material. These crystals should not have a net electrically active impurity concentration greater than 10/sup 10/cm/sup -3/ and be essentially free of charge trapping defects. Such perfect crystals of germanium can be grown only because of the highly favorable chemical and physical properties of this element. However, ten years of laboratory scale and commercial experience has still not made the production of such crystals routine. The origin and control of many impurities and electrically active defect complexes is now fairly well understood but regular production is often interrupted for long periods due to the difficulty of achieving the required high purity or to charge trapping in detectors made from crystals seemingly grown under the required conditions. The compromises involved in the selection of zone refining and crystal grower parts and ambients is discussed and the difficulty in controlling the purity of key elements in the process is emphasized. The consequences of growing in a hydrogen ambient are discussed in detail and it is shown how complexes of neutral defects produce electrically active centers.

  11. 3. SOUTHWEST VIEW OF LOW PURITY BULK OXYGEN BUILDING, WITH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. SOUTHWEST VIEW OF LOW PURITY BULK OXYGEN BUILDING, WITH THE LINDE LOW PURITY OXYGEN FRACTIONATING TOWERS ON LEFT. - U.S. Steel Duquesne Works, Fuel & Utilities Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  12. Extreme argon purity in a large, non-evacuated cryostat

    SciTech Connect

    Tope, Terry; Adamowski, Mark; Carls, B.; Hahn, A.; Jaskierny, W.; Jostlein, H.; Kendziora, C.; Lockwitz, S.; Pahlka, B.; Plunkett, R.; Pordes, S.; Rebel, B.; Schmitt, R.; Skup, E.; Stancari, M.; Yang, T.

    2014-01-29

    Liquid Argon Time Projection Chambers (LArTPCs) show promise as scalable devices for the large detectors needed for long-baseline neutrino oscillation physics. Over the last several years at Fermilab a staged approach to developing the technology for large detectors has been developed. The TPC detectors require ultra-pure liquid argon with respect to electronegative contaminants such as oxygen and water. The tolerable electronegative contamination level may be as pure as 60 parts per trillion of oxygen. Three liquid argon cryostats operated at Fermilab have achieved the extreme purity required by TPCs. These three cryostats used evacuation to remove atmospheric contaminants as the first purification step prior to filling with liquid argon. Future physics experiments may require very large detectors with tens of kilotonnes of liquid argon mass. The capability to evacuate such large cryostats adds significant cost to the cryostat itself in addition to the cost of a large scale vacuum pumping system. This paper describes a 30 ton liquid argon cryostat at Fermilab which uses purging to remove atmospheric contaminants instead of evacuation as the first purification step. This cryostat has achieved electronegative contamination levels better than 60 parts per trillion of oxygen equivalent. The results of this liquid argon purity demonstration will strongly influence the design of future TPC cryostats.

  13. Time-independent eigenstate-free calculation of vibronic spectra beyond the harmonic approximation.

    PubMed

    Petrenko, Taras; Rauhut, Guntram

    2015-12-21

    The calculation of vibronic spectra and resonance Raman intensities can be performed on the basis of the Raman wavefunction (RWF) formalism. In general, the well-known sum-over-states (SOS) and time-dependent methods can be applied for calculating the RWF. We present an alternative route in which the RWF is determined pointwise in a spectral range on the basis of the inhomogeneous Schrödinger equation using an iterative subspace method, in which explicit state-by-state calculations of vibrational eigenstates are bypassed. We study this approach within the framework of vibrational configuration interaction theory in conjunction with high-level electronic structure calculations for the multidimensional Born-Oppenheimer potential energy surface. The method benefits from an implicit account of interference effects between vibrational states, so that its computational cost correlates with the required resolution in the spectra. The accuracy and efficiency of the method with respect to comparable SOS calculations are tested for the simulation of the photoelectron spectra of ClO2, HS2 (-), ZnOH(-), and Zn(H2O)(+).

  14. Singular eigenstates in the even(odd) length Heisenberg spin chain

    NASA Astrophysics Data System (ADS)

    Ranjan Giri, Pulak; Deguchi, Tetsuo

    2015-05-01

    We study the implications of the regularization for the singular solutions on the even(odd) length spin-1/2 XXX chains in some specific down-spin sectors. In particular, the analytic expressions of the Bethe eigenstates for three down-spin sector have been obtained along with their numerical forms in some fixed length chains. For an even-length chain if the singular solutions \\{{{λ }α }\\} are invariant under the sign changes of their rapidities \\{{{λ }α }\\}=\\{-{{λ }α }\\}, then the Bethe ansatz equations are reduced to a system of (M-2)/2((M-3)/2) equations in an even (odd) down-spin sector. For an odd N length chain in the three down-spin sector, it has been analytically shown that there exist singular solutions in any finite length of the spin chain of the form N=3(2k+1) with k=1,2,3,\\cdots . It is also shown that there exist no singular solutions in the four down-spin sector for some odd-length spin-1/2 XXX chains.

  15. The Analysis of Eigenstates of a Few Generalized Quantum Baker’s Maps Using Hadamard and Related Transforms

    NASA Astrophysics Data System (ADS)

    Meenakshisundaram, N.

    Application of the Hadamard and related transforms on a few generalized quantum baker’s maps have been studied. Effectiveness of the Hadamard transform and a new transform which combines the Fourier and the Hadamard transforms, for simplifying the eigenstates or resonances of the quantization of a few generalized baker’s map namely tetradic baker and lazy baker’s map when the Hilbert space dimension is power of 2 has been done by comparing the participation ratios in the transformed basis with respect to the position basis. Several special family of states based on their maximal compression in either Hadamard transform or the new transform are identified and they are related to the ubiquitous Thue-Morse and allied sequences. Evidence is provided that these special family of states as well as average over all eigenstates exhibits multifractal nature.

  16. Communication: Quantum six-dimensional calculations of the coupled translation-rotation eigenstates of H2O@C60.

    PubMed

    Felker, Peter M; Bačić, Zlatko

    2016-05-28

    We report rigorous quantum calculations of the translation-rotation (TR) eigenstates of para- and ortho-H2O@C60. They provide a comprehensive description of the dynamical behavior of H2O inside the fullerene having icosahedral (Ih) symmetry. The TR eigenstates are assigned in terms of the irreducible representations of the proper symmetry group of H2O@C60, as well as the appropriate translational and rotational quantum numbers. The coupling between the orbital and the rotational angular momenta of the caged H2O gives rise to the total angular momentum λ, which additionally labels each TR level. The calculated TR levels allow tentative assignments of a number of transitions in the recent experimental INS spectra of H2O@C60 that have not been assigned previously.

  17. A xenon gas purity monitor for EXO

    NASA Astrophysics Data System (ADS)

    Dobi, A.; Hall, C.; Herrin, S.; Odian, A.; Prescott, C. Y.; Rowson, P. C.; Ackerman, N.; Aharmin, B.; Auger, M.; Barbeau, P. S.; Barry, K.; Benitez-Medina, C.; Breidenbach, M.; Cook, S.; Counts, I.; Daniels, T.; DeVoe, R.; Dolinski, M. J.; Donato, K.; Fairbank, W.; Farine, J.; Giroux, G.; Gornea, R.; Graham, K.; Gratta, G.; Green, M.; Hagemann, C.; Hall, K.; Hallman, D.; Hargrove, C.; Karelin, A.; Kaufman, L. J.; Kuchenkov, A.; Kumar, K.; Lacey, J.; Leonard, D. S.; LePort, F.; Mackay, D.; MacLellan, R.; Mong, B.; Montero Díez, M.; Müller, A. R.; Neilson, R.; Niner, E.; O'Sullivan, K.; Piepke, A.; Pocar, A.; Pushkin, K.; Rollin, E.; Sinclair, D.; Slutsky, S.; Stekhanov, V.; Twelker, K.; Voskanian, N.; Vuilleumier, J.-L.; Wichoski, U.; Wodin, J.; Yang, L.; Yen, Y.-R.

    2011-12-01

    We discuss the design, operation, and calibration of two versions of a xenon gas purity monitor (GPM) developed for the EXO double beta decay program. The devices are sensitive to concentrations of oxygen well below 1 ppb at an ambient gas pressure of one atmosphere or more. The theory of operation of the GPM is discussed along with the interactions of oxygen and other impurities with the GPM's tungsten filament. Lab tests and experiences in commissioning the EXO-200 double beta decay experiment are described. These devices can also be used on other noble gases.

  18. High-purity thermoacoustic isotope enrichment.

    PubMed

    Swift, G W; Geller, D A; Backhaus, S N

    2014-08-01

    In a tube many wavelengths long, thermoacoustic separation of a gas mixture can produce very high purities. A flexible wall allows a spatially continuous supply of acoustic power into such a long tube. Coiling the tube and immersing it in a fluid lets a single-wavelength, circulating, traveling pressure wave in the fluid drive all the wavelengths in the tube wall and gas. Preliminary measurements confirm many aspects of the concept with neon ((20)Ne and (22)Ne) and highlight some challenges of practical implementation.

  19. Surface purity control during XMASS detector refurbishment

    SciTech Connect

    Kobayashi, Kazuyoshi

    2015-08-17

    The XMASS project aims at detecting dark matter, pp and {sup 7}Be solar neutrinos, and neutrino less double beta decay using large volume of pure liquid xenon. The first physics target of the XMASS project is to detect dark matter with 835 kg liquid xenon. After the commissioning runs, XMASS detector was refurbished to minimize the background contribution mainly from PMT sealing material and we restarted data taking in November 2013. We report how we control surface purity, especially how we prevent radon daughter accumulation on the detector copper surface, during XMASS detector refurbishment. The result and future plan of XMASS are also reported.

  20. Method for preparing high purity vanadium

    DOEpatents

    Schmidt, F.; Carlson, O.N.

    1984-05-16

    A method for preparing high purity vanadium having a low silicon content has been developed. Vanadium pentoxide is reduced with a stoichiometric, or slightly deficient amount of aluminum to produce a vanadium-aluminum alloy containing an excess of oxygen. Silicon is removed by electron-beam melting the alloy under oxidizing conditions to promote the formation of SiO which is volatile at elevated temperatures. Excess oxygen is removed by heating the alloy in the presence of calcium metal to form calcium oxide.

  1. Method for preparing high purity vanadium

    DOEpatents

    Schmidt, Frederick; Carlson, O. Norman

    1986-09-09

    A method for preparing high purity vanadium having a low silicon content has been developed. Vanadium pentoxide is reduced with a stoichiometric, or slightly deficient amount of aluminum to produce a vanadium-aluminum alloy containing an excess of oxygen. Silicon is removed by electron-beam melting the alloy under oxidizing conditions to promote the formation of SiO which is volatile at elevated temperatures. Excess oxygen is removed by heating the alloy in the presence of calcium metal to form calcium oxide.

  2. Metrological approaches to organic chemical purity: primary reference materials for vitamin D metabolites.

    PubMed

    Nelson, Michael A; Bedner, Mary; Lang, Brian E; Toman, Blaza; Lippa, Katrice A

    2015-11-01

    Given the critical role of pure, organic compound primary reference standards used to characterize and certify chemical Certified Reference Materials (CRMs), it is essential that associated mass purity assessments be fit-for-purpose, represented by an appropriate uncertainty interval, and metrologically sound. The mass fraction purities (% g/g) of 25-hydroxyvitamin D (25(OH)D) reference standards used to produce and certify values for clinical vitamin D metabolite CRMs were investigated by multiple orthogonal quantitative measurement techniques. Quantitative (1)H-nuclear magnetic resonance spectroscopy (qNMR) was performed to establish traceability of these materials to the International System of Units (SI) and to directly assess the principal analyte species. The 25(OH)D standards contained volatile and water impurities, as well as structurally-related impurities that are difficult to observe by chromatographic methods or to distinguish from the principal 25(OH)D species by one-dimensional NMR. These impurities have the potential to introduce significant biases to purity investigations in which a limited number of measurands are quantified. Combining complementary information from multiple analytical methods, using both direct and indirect measurement techniques, enabled mitigation of these biases. Purities of 25(OH)D reference standards and associated uncertainties were determined using frequentist and Bayesian statistical models to combine data acquired via qNMR, liquid chromatography with UV absorbance and atmospheric pressure-chemical ionization mass spectrometric detection (LC-UV, LC-ACPI-MS), thermogravimetric analysis (TGA), and Karl Fischer (KF) titration.

  3. Cognitions about bodily purity attenuate stress perception

    PubMed Central

    Kaspar, Kai; Cames, Sarah

    2016-01-01

    Based on the assumption that physical purity is associated with a clean slate impression, we examined how cognitions about bodily cleanliness modulate stress perception. Participants visualized themselves in a clean or dirty state before reporting the frequency of stress-related situations experienced in the past. In Study 1 (n = 519) and Study 2 (n = 647) cleanliness versus dirtiness cognitions reliably reduced stress perception. Further results and a mediation analysis revealed that this novel effect was not simply driven by participants’ cognitive engagement in stress recall. Moreover, we found that participants’ temporal engagement in the recall of past stressful events negatively correlated with the amount of perceived stress, indicating an ease-of-retrieval phenomenon. However, a direct manipulation of the number of recalled stressful events in Study 3 (n = 792) showed the opposite effect: few versus many recalled events increased the perceived frequency of past stress-related situations. Overall, these novel results indicate an interesting avenue for future research on cognitively oriented stress reduction interventions, add to the literature on purity-related clean slate effects, and may help to better understand washing rituals in patients with obsessive-compulsive disorders. PMID:27934971

  4. Cell culture purity issues and DFAT cells

    SciTech Connect

    Wei, Shengjuan; Bergen, Werner G.; Zan, Linsen; Dodson, Michael V.

    2013-04-12

    Highlights: •DFAT cells are progeny cells derived from dedifferentiated mature adipocytes. •Common problems in this research is potential cell contamination of initial cultures. •The initial cell culture purity is crucial in DFAT cell research field. -- Abstract: Dedifferentiation of mature adipocytes, in vitro, has been pursued/documented for over forty years. The subsequent progeny cells are named dedifferentiated adipocyte-derived progeny cells (DFAT cells). DFAT cells are proliferative and likely to possess mutilineage potential. As a consequence, DFAT cells and their progeny/daughter cells may be useful as a potential tool for various aspects of tissue engineering and as potential vectors for the alleviation of several disease states. Publications in this area have been increasing annually, but the purity of the initial culture of mature adipocytes has seldom been documented. Consequently, it is not always clear whether DFAT cells are derived from dedifferentiated mature (lipid filled) adipocytes or from contaminating cells that reside in an impure culture.

  5. Mass

    SciTech Connect

    Quigg, Chris

    2007-12-05

    In the classical physics we inherited from Isaac Newton, mass does not arise, it simply is. The mass of a classical object is the sum of the masses of its parts. Albert Einstein showed that the mass of a body is a measure of its energy content, inviting us to consider the origins of mass. The protons we accelerate at Fermilab are prime examples of Einsteinian matter: nearly all of their mass arises from stored energy. Missing mass led to the discovery of the noble gases, and a new form of missing mass leads us to the notion of dark matter. Starting with a brief guided tour of the meanings of mass, the colloquium will explore the multiple origins of mass. We will see how far we have come toward understanding mass, and survey the issues that guide our research today.

  6. Mass

    SciTech Connect

    Chris Quigg

    2007-12-05

    In the classical physics we inherited from Isaac Newton, mass does not arise, it simply is. The mass of a classical object is the sum of the masses of its parts. Albert Einstein showed that the mass of a body is a measure of its energy content, inviting us to consider the origins of mass. The protons we accelerate at Fermilab are prime examples of Einsteinian matter: nearly all of their mass arises from stored energy. Missing mass led to the discovery of the noble gases, and a new form of missing mass leads us to the notion of dark matter. Starting with a brief guided tour of the meanings of mass, the colloquium will explore the multiple origins of mass. We will see how far we have come toward understanding mass, and survey the issues that guide our research today.

  7. State selectivity and eigenstate control in molecules using multiple CW lasers

    NASA Astrophysics Data System (ADS)

    Kirova, Teodora V.

    A novel method for designing target states with desirable properties by using a strong laser field has been developed. In a molecular system with two closely spaced levels application of a strong laser is shown to lead to a controllable mixture of states. A "control equation" governing the relation between the Rabi frequency and the detuning of the coupling field has been derived on the basis of the dressed-states approach. A more intuitive way of achieving mixing in the perturbed eigenstates has been investigated by using the Autler-Townes (AT) effect in the case of weak initial mixing. A condition for resonant enhancing of the mixing has been obtained. The theoretical analysis is based on the dressed states approach as well as the density matrix formalism. While the dressed states approach explains the creation of the target states under the action of the strong coupling field, the density matrix formalism accounts also for such physical phenomena as spontaneous decay of the molecular levels and describes the molecular absorption and level populations. Thus, it can be used to demonstrate the creation of the target states via the absorption behavior of the system in the presence of the strong field. The target state creation and the Autler-Townes splitting have been applied to realistic systems (molecular lithium) for the case of singlet-triplet initial mixing. The control equations as well as the condition for the AT effect have been modified to reflect the magnetic quantum number (MJ) degeneracy in all the molecular levels. The design of target states and states mixed via AT splitting with a pre-selected magnetic quantum number has been demonstrated by calculating the absorption spectra of the weak field. The possibility for direct measurement of spin-orbit interaction has been shown even in the presence of level degeneracy. The prospect of target states creation and molecular magnetic sublevel selectivity has been discussed in case of inhomogeneously broadened

  8. Process for producing high purity aromatic compounds

    SciTech Connect

    Mayes, W.W.

    1980-05-20

    High-purity C7 and/or C8 aromatic hydrocarbons are produced by reforming a C7 or C8 full boiling carbon number naphtha feed fraction or combinations thereof under reforming conditions of sufficient severity to convert essentially all of the nonaromatic portion of the naphtha feed boiling in the C7 to C8 aromatic boiling range to C7 and/or C8 aromatics, and then separating the reformate by fractional distillation into highpurity fractions of C7 and/or C8 aromatic hydrocarbons. Preferably, the C7 and/or C8 full boiling carbon number naphtha feed fraction is reformed in a plurality of reformer reaction stages with increasingly more severe conditions in order to maximize the yield of the C7 and C8 aromatics.

  9. Workshop on Preserving High Purity Uranium-233

    SciTech Connect

    Krichinsky, Alan M; Giaquinto, Joseph; Canaan, R Douglas {Doug}

    2016-01-01

    A workshop was held on at the MARC X conference to provide a forum for the scientific community to communicate needs for high-purity 233U and its by-products in order to preserve critical items otherwise slated for downblending and disposal. Currently, only a small portion of the U.S. holdings of separated 233U is being preserved. However, many additional kilograms of 233U (>97% pure) still are destined to be downblended which will permanently destroy their potential value for many other applications. It is not likely that this material will ever be replaced due to a lack of operating production capability. Summaries of information conveyed at the workshop and feedback obtained from the scientific community are presented herein.

  10. Cell culture purity issues and DFAT cells.

    PubMed

    Wei, Shengjuan; Bergen, Werner G; Hausman, Gary J; Zan, Linsen; Dodson, Michael V

    2013-04-12

    Dedifferentiation of mature adipocytes, in vitro, has been pursued/documented for over forty years. The subsequent progeny cells are named dedifferentiated adipocyte-derived progeny cells (DFAT cells). DFAT cells are proliferative and likely to possess mutilineage potential. As a consequence, DFAT cells and their progeny/daughter cells may be useful as a potential tool for various aspects of tissue engineering and as potential vectors for the alleviation of several disease states. Publications in this area have been increasing annually, but the purity of the initial culture of mature adipocytes has seldom been documented. Consequently, it is not always clear whether DFAT cells are derived from dedifferentiated mature (lipid filled) adipocytes or from contaminating cells that reside in an impure culture.

  11. Production of high purity titanium by electrorefining

    SciTech Connect

    Kanda, Minoru; Sato, Kazusuke; Kimura, Etsuji

    1996-10-01

    The behavior of impurities in electrorefining of Ti by NaCl-KCl-TiClx molten salts and the production process of its molten salts have been studied. As a result, purification of salts, materials for the apparatus and the quality of anode Ti were important for the production of high purity Ti. By using purified molten salts and the apparatus constructed of Ni, impurities of the Ti deposit, such as Fe, Ni, could be lowered to about 0.01 ppm. The contents of Al and Cr of this Ti were about 0.1 ppm. Volatile impurities were removed from the Ti obtained in this process by electron beam melting and Ti ingots with grades in excess of 6N (except for gas elements) were obtained.

  12. Processing to obtain high-purity gallium

    NASA Astrophysics Data System (ADS)

    Bautista, Renato G.

    2003-03-01

    Gallium has become increasingly popular as a substrate material for electronic devices. Aside from ore, gallium can be obtained from such industrial sources as the Bayer process caustic liquor that is a byproduct of bauxite processing, flue dust removed from the fume-collection system in plants that produce aluminum by the electrolytic process, zinc refinery residues, gallium scrap materials, and coal fly ash. The purification process for gallium can start with solvent-extraction processes where the concentrations of impurities, especially metals, are reduced to the ppm range. This article describes how ultra-purification techniques can be employed to reduce the undesirable impurities to the low ppb range. The various procedures described give an idea as to the extent of work needed to obtain and prepare high-purity gallium for electronic application.

  13. Determination of chemical purity and isotopic composition of natural and carbon-13-labeled arsenobetaine bromide standards by quantitative(1)H-NMR.

    PubMed

    Le, Phuong-Mai; Ding, Jianfu; Leek, Donald M; Mester, Zoltan; Robertson, Gilles; Windust, Anthony; Meija, Juris

    2016-10-01

    In this study, we report the characterization of three arsenobetaine-certified reference materials by quantitative NMR. We have synthesized an arsenobetaine bromide high-purity standard of natural isotopic composition (ABET-1) and two carbon-13-labeled isotopic standards (BBET-1 and CBET-1). Assignments of the chemical purity and isotopic composition are not trivial in the case of arsenobetaine, and in this study we utilized quantitative(1)H-NMR techniques for the determination of the mass fractions (chemical purity). The isotopic purity of all three standards was also assessed by NMR from the carbon-13 satellite signals. The standards are non-hygroscopic, high-purity (ca. 0.99 g/g), and the carbon-13 enrichment for both isotopic standards is x((13)C)≈0.99. These standards are designed for use as primary calibrators for mass spectrometric determination of arsenobetaine in environmental samples.

  14. Industrialization progress of high-purity hafnium for optical components

    NASA Astrophysics Data System (ADS)

    Wang, Lijun; Zhang, Shunli; Zhang, Jiandong; Chen, Yang; Peng, Jiaqing

    2016-03-01

    Hafnium oxide, hafnium crystal bar and high-purity hafnium were prepared using extraction separation, reduction, electrolytic refining, iodide refining and electron beam melting process by General Research Institute for Nonferrous Metals. A hundreds-kilogram production line has been built. The purity of the high-purity hafnium was Zr/(Zr+Hf) <0.3wt% and Zr+Hf>99.99wt%, which enables a high laser induced damage threshold.

  15. Uncertainty estimates of purity measurements based on current information: toward a "live validation" of purity methods.

    PubMed

    Apostol, Izydor; Kelner, Drew; Jiang, Xinzhao Grace; Huang, Gang; Wypych, Jette; Zhang, Xin; Gastwirt, Jessica; Chen, Kenneth; Fodor, Szilan; Hapuarachchi, Suminda; Meriage, Dave; Ye, Frank; Poppe, Leszek; Szpankowski, Wojciech

    2012-12-01

    To predict precision and other performance characteristics of chromatographic purity methods, which represent the most widely used form of analysis in the biopharmaceutical industry. We have conducted a comprehensive survey of purity methods, and show that all performance characteristics fall within narrow measurement ranges. This observation was used to develop a model called Uncertainty Based on Current Information (UBCI), which expresses these performance characteristics as a function of the signal and noise levels, hardware specifications, and software settings. We applied the UCBI model to assess the uncertainty of purity measurements, and compared the results to those from conventional qualification. We demonstrated that the UBCI model is suitable to dynamically assess method performance characteristics, based on information extracted from individual chromatograms. The model provides an opportunity for streamlining qualification and validation studies by implementing a "live validation" of test results utilizing UBCI as a concurrent assessment of measurement uncertainty. Therefore, UBCI can potentially mitigate the challenges associated with laborious conventional method validation and facilitates the introduction of more advanced analytical technologies during the method lifecycle.

  16. Dynamic shear deformation in high purity Fe

    SciTech Connect

    Cerreta, Ellen K; Bingert, John F; Trujillo, Carl P; Lopez, Mike F; Gray, George T

    2009-01-01

    The forced shear test specimen, first developed by Meyer et al. [Meyer L. et al., Critical Adiabatic Shear Strength of Low Alloyed Steel Under Compressive Loading, Metallurgical Applications of Shock Wave and High Strain Rate Phenomena (Marcel Decker, 1986), 657; Hartmann K. et al., Metallurgical Effects on Impact Loaded Materials, Shock Waves and High Strain rate Phenomena in Metals (Plenum, 1981), 325-337.], has been utilized in a number of studies. While the geometry of this specimen does not allow for the microstructure to exactly define the location of shear band formation and the overall mechanical response of a specimen is highly sensitive to the geometry utilized, the forced shear specimen is useful for characterizing the influence of parameters such as strain rate, temperature, strain, and load on the microstructural evolution within a shear band. Additionally, many studies have utilized this geometry to advance the understanding of shear band development. In this study, by varying the geometry, specifically the ratio of the inner hole to the outer hat diameter, the dynamic shear localization response of high purity Fe was examined. Post mortem characterization was performed to quantify the width of the localizations and examine the microstructural and textural evolution of shear deformation in a bcc metal. Increased instability in mechanical response is strongly linked with development of enhanced intergranular misorientations, high angle boundaries, and classical shear textures characterized through orientation distribution functions.

  17. Actinium radioisotope products of enhanced purity

    SciTech Connect

    Meikrantz, David Herbert; Todd, Terry Allen; Tranter, Troy Joseph; Horwitz, E. Philip

    2010-06-15

    A product includes actinium-225 (.sup.225Ac) and less than about 1 microgram (.mu.g) of iron (Fe) per millicurie (mCi) of actinium-225. The product may have a radioisotopic purity of greater than about 99.99 atomic percent (at %) actinium-225 and daughter isotopes of actinium-225, and may be formed by a method that includes providing a radioisotope mixture solution comprising at least one of uranium-233 (.sup.233U) and thorium-229 (.sup.229Th), extracting the at least one of uranium-233 and thorium-229 into an organic phase, substantially continuously contacting the organic phase with an aqueous phase, substantially continuously extracting actinium-225 into the aqueous phase, and purifying the actinium-225 from the aqueous phase. In some embodiments, the product may include less than about 1 nanogram (ng) of iron per millicurie (mCi) of actinium-225, and may include less than about 1 microgram (.mu.g) each of magnesium (Mg), Chromium (Cr), and manganese (Mn) per millicurie (mCi) of actinium-225.

  18. Biaxial deformation in high purity aluminum

    DOE PAGES

    Livescu, V.; Bingert, J. F.; Liu, C.; ...

    2015-09-25

    The convergence of multiple characterization tools has been applied to investigate the relationship of microstructure on damage evolution in high purity aluminum. The extremely coarse grain size of the disc-shaped sample provided a quasi-two dimensional structure from which the location of surface-measured features could be inferred. In particular, the role of pre-existing defects on damage growth was accessible due to the presence of casting porosity in the aluminum. Micro tomography, electron backscatter diffraction, and digital image correlation were applied to interrogate the sample in three dimensions. Recently micro-bulge testing apparatus was used to deform the pre-characterized disc of aluminum inmore » biaxial tension, and related analysis techniques were applied to map local strain fields. Subsequent post-mortem characterization of the failed sample was performed to correlate structure to damaged regions. We determined that strain localization and associated damage was most strongly correlated with grain boundary intersections and plastic anisotropy gradients between grains. Pre-existing voids played less of an apparent role than was perhaps initially expected. Finally, these combined techniques provide insight to the mechanism of damage initiation, propagation, and failure, along with a test bed for predictive damage models incorporating anisotropic microstructural effects.« less

  19. Biaxial deformation in high purity aluminum

    SciTech Connect

    Livescu, V.; Bingert, J. F.; Liu, C.; Lovato, M. L.; Patterson, B. M.

    2015-09-25

    The convergence of multiple characterization tools has been applied to investigate the relationship of microstructure on damage evolution in high purity aluminum. The extremely coarse grain size of the disc-shaped sample provided a quasi-two dimensional structure from which the location of surface-measured features could be inferred. In particular, the role of pre-existing defects on damage growth was accessible due to the presence of casting porosity in the aluminum. Micro tomography, electron backscatter diffraction, and digital image correlation were applied to interrogate the sample in three dimensions. Recently micro-bulge testing apparatus was used to deform the pre-characterized disc of aluminum in biaxial tension, and related analysis techniques were applied to map local strain fields. Subsequent post-mortem characterization of the failed sample was performed to correlate structure to damaged regions. We determined that strain localization and associated damage was most strongly correlated with grain boundary intersections and plastic anisotropy gradients between grains. Pre-existing voids played less of an apparent role than was perhaps initially expected. Finally, these combined techniques provide insight to the mechanism of damage initiation, propagation, and failure, along with a test bed for predictive damage models incorporating anisotropic microstructural effects.

  20. 10 CFR 36.63 - Pool water purity.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Pool water purity. 36.63 Section 36.63 Energy NUCLEAR... § 36.63 Pool water purity. (a) Pool water purification system must be run sufficiently to maintain the conductivity of the pool water below 20 microsiemens per centimeter under normal circumstances. If pool...

  1. 10 CFR 36.63 - Pool water purity.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Pool water purity. 36.63 Section 36.63 Energy NUCLEAR... § 36.63 Pool water purity. (a) Pool water purification system must be run sufficiently to maintain the conductivity of the pool water below 20 microsiemens per centimeter under normal circumstances. If pool water...

  2. 10 CFR 36.63 - Pool water purity.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Pool water purity. 36.63 Section 36.63 Energy NUCLEAR... § 36.63 Pool water purity. (a) Pool water purification system must be run sufficiently to maintain the conductivity of the pool water below 20 microsiemens per centimeter under normal circumstances. If pool water...

  3. Determination of continuous variable entanglement by purity measurements.

    PubMed

    Adesso, Gerardo; Serafini, Alessio; Illuminati, Fabrizio

    2004-02-27

    We classify the entanglement of two-mode Gaussian states according to their degree of total and partial mixedness. We derive exact bounds that determine maximally and minimally entangled states for fixed global and marginal purities. This characterization allows for an experimentally reliable estimate of continuous variable entanglement based on measurements of purity.

  4. 10 CFR 36.63 - Pool water purity.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... § 36.63 Pool water purity. (a) Pool water purification system must be run sufficiently to maintain the conductivity of the pool water below 20 microsiemens per centimeter under normal circumstances. If pool water... 10 Energy 1 2012-01-01 2012-01-01 false Pool water purity. 36.63 Section 36.63 Energy...

  5. 6. LOOKING WEST IN LOW PURITY BULK OXYGEN BUILDING AT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. LOOKING WEST IN LOW PURITY BULK OXYGEN BUILDING AT STEAM TURBINE END OF TWO ALLIS-CHALMERS AXIAL AIR COMPRESSORS FOR 1000 TON PER DAY HIGH PURITY OXYGEN MAKING PLANT. - U.S. Steel Duquesne Works, Fuel & Utilities Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  6. 5. LOOKING WEST IN LOW PURITY BULK OXYGEN BUILDING AT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. LOOKING WEST IN LOW PURITY BULK OXYGEN BUILDING AT STEAM TURBINE END OF TWO ALLIS-CHALMER AXIAL AIR COMPRESSORS FOR 1000 TON PER DAY HIGH PURITY OXYGEN MAKING PLANT. - U.S. Steel Duquesne Works, Fuel & Utilities Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  7. High Spectral Purity, Narrow Linewidth Laser Transmitter for Dial Measurements

    NASA Technical Reports Server (NTRS)

    Singh, U. N.; Flamant, P. H.

    1986-01-01

    A laser transmission with very high degree of spectral purity was described. Amplified Spontaneous Emission (ASE) dependence on the oscillator energy and the detuning away from the gain curve center are demonstrated. The effects of both finite laser linewidth and spectral purity on humidity measurements are experimentally demonstrated.

  8. 10 CFR 36.63 - Pool water purity.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 1 2013-01-01 2013-01-01 false Pool water purity. 36.63 Section 36.63 Energy NUCLEAR... § 36.63 Pool water purity. (a) Pool water purification system must be run sufficiently to maintain the conductivity of the pool water below 20 microsiemens per centimeter under normal circumstances. If pool...

  9. Preparation and Evaluation of High-Purity La2O3

    NASA Astrophysics Data System (ADS)

    Lee, Gwang Seop; Uchikoshi, Masahito; Mimura, Kouji; Isshiki, Minoru

    2010-06-01

    A separation procedure based on extraction chromatography using the di(2-ethylhexyl) phosphoric acid (D2EHPA) impregnated resin, anion exchange with DIAION SA 10 resin, and oxalate precipitation has been developed for the preparation of high-purity La2O3 in hydrochloric acid media at a high La concentration. The metallic impurities Ce, Pr, Nd, Sm, K, Mg, Ca, Zn, Cu, Co, Mn, Pb, Al, In, and Fe, but not Bi, were removed efficiently from La by extraction chromatography using a D2EHPA impregnated resin. The Bi was separated from the La by anion exchange (DIAION SA 10) separation. Thus, a high-purity LaCl3 solution was obtained by anion exchange separation and extraction chromatography. La2O3 was prepared from the purified LaCl3 solution by oxalate precipitation. Glow discharge mass spectrometry was applied for purity evaluation of the prepared La2O3. The purity of the prepared La2O3 was more than 99.9998 pct total rare earth oxide.

  10. High-purity silicon for solar cell applications

    NASA Technical Reports Server (NTRS)

    Dosaj, V. D.; Hunt, L. P.; Schei, A.

    1978-01-01

    The article discusses the production of solar cells from high-purity silicon. The process consists of reducing the level of impurities in the raw materials, preventing material contamination before and after entering the furnace, and performing orders-of-magnitude reduction of metal impurity concentrations. The high-purity raw materials are considered with reference to carbon reductants, silica, and graphite electrodes. Attention is also given to smelting experiments used to demonstrate, in an experimental-scale furnace, the production of high-purity SoG-Si. It is found that high-purity silicon may be produced from high-purity quartz and chemically purified charcoal in a 50-kVA arc furnace. The major contamination source is shown to be impurities from the carbon reducing materials.

  11. Relations between entanglement and purity in non-Markovian dynamics

    NASA Astrophysics Data System (ADS)

    González-Gutiérrez, Carlos A.; Román-Ancheyta, Ricardo; Espitia, Diego; Lo Franco, Rosario

    2016-09-01

    Knowledge of the relationships among different features of quantumness, like entanglement and state purity, is important from both fundamental and practical viewpoints. Yet, this issue remains little explored in dynamical contexts for open quantum systems. We address this problem by studying the dynamics of entanglement and purity for two-qubit systems using paradigmatic models of radiation-matter interaction, with a qubit being isolated from the environment (spectator configuration). We show the effects of the corresponding local quantum channels on an initial two-qubit pure entangled state in the concurrence-purity diagram and find the conditions which enable dynamical closed formulas of concurrence, used to quantify entanglement, as a function of purity. We finally discuss the usefulness of these relations in assessing entanglement and purity thresholds which allow noisy quantum teleportation. Our results provide new insights about how different properties of composite open quantum systems behave and relate each other during quantum evolutions.

  12. Production of ultrahigh purity copper using waste copper nitrate solution.

    PubMed

    Choi, J Y; Kim, D S

    2003-04-25

    The production of ultrahigh purity copper (99.9999%) by electrolysis in the presence of a cementation barrier has been attempted employing a waste nitric copper etching solution as the electrolyte. The amount of copper deposited on the cathode increased almost linearly with electrolysis time and the purity of copper was observed to increase as the electrolyte concentration was increased. At some point, however, as the electrolyte concentration increased, the purity of copper decreased slightly. As the total surface area of cementation barrier increased, the purity of product increased. The electrolyte temperature should be maintained below 35 degrees C in the range of investigated electrolysis conditions to obtain the ultrahigh purity copper. Considering that several industrial waste solutions contain valuable metallic components the result of present study may support a claim that electrowinning is a very desirable process for their treatment and recovery.

  13. High-purity silicon for solar cell applications

    NASA Technical Reports Server (NTRS)

    Dosaj, V. D.; Hunt, L. P.; Schei, A.

    1978-01-01

    The article discusses the production of solar cells from high-purity silicon. The process consists of reducing the level of impurities in the raw materials, preventing material contamination before and after entering the furnace, and performing orders-of-magnitude reduction of metal impurity concentrations. The high-purity raw materials are considered with reference to carbon reductants, silica, and graphite electrodes. Attention is also given to smelting experiments used to demonstrate, in an experimental-scale furnace, the production of high-purity SoG-Si. It is found that high-purity silicon may be produced from high-purity quartz and chemically purified charcoal in a 50-kVA arc furnace. The major contamination source is shown to be impurities from the carbon reducing materials.

  14. Electromagnetic eigenstates and the field of an oscillating point electric dipole in a flat-slab composite structure

    NASA Astrophysics Data System (ADS)

    Farhi, Asaf; Bergman, David J.

    2016-06-01

    An exact calculation of the local electric field E (r ) is described for the case of a time-dependent point electric dipole p e-i ω t in the top layer of an ɛ2, ɛ1, ɛ2 three parallel slabs composite structure, where the ɛ1 layer has a finite thickness 2 d but the ɛ2 layers are infinitely thick. For this purpose we first calculate all the eigenstates of the full Maxwell equations for the case where μ =1 everywhere in the system. The eigenvalues appear as special, nonphysical values of ɛ1 when ɛ2 is given. These eigenstates are then used to develop an exact expansion for the physical values of E (r ) in the system characterized by physical values of ɛ1(ω ) and ɛ2(ω ) . Results are compared with those of a previous calculation of the local field of a time-dependent point charge in the quasistatic regime. Numerical results are shown for the local electric field in practically important configurations where attaining an optical image with subwavelength resolution has practical significance.

  15. High Purity Zirconium Tetrafluoride For Fluoride Glass Applications

    NASA Astrophysics Data System (ADS)

    Withers, Howard P.; Monk, V. A.; Cooper, G. A.

    1989-06-01

    A totally anhydrous process has been developed for the preparation of high purity zirconium tetrafluoride for use in low loss fluoride glass applications. The ZrF4 purityis 99.99997% with respect to all transition elements (excluding HO based on analysis by spark source mass spectrometry (SSMS) and graphite furnace/atomic absorption spectroscopy (GF/AA). The only transition elements detected by these techniques were Fe, Ni and Cr, while Co and Cu were consistently below the detection limits. The anhydrous nature of the process, which is strictly maintained by the choice of reactants, affords product with very low oxide and hydroxide content. Total oxygen concentrations of less than 10 ppm have been measured by the inert gas fusion technique. A ZBLAN glass composition prepared using this ZrF4 showed extremely low UV absorption having an absorption constant of 1 cm-1 at 198 nm. ZrF4 from this process was also used in a ZBLAN glass fiber whose minimum optical loss was measured at 6.3 dB/km over 150 meters of fiber. The process is straightforward to scale up and has also been demonstrated to be useful for the preparation of HfF4, BaF2, A1F3 and LaF3.

  16. State-independent purity and fidelity of quantum operations

    NASA Astrophysics Data System (ADS)

    Kong, Fan-Zhen; Zong, Xiao-Lan; Yang, Ming; Cao, Zhuo-Liang

    2016-04-01

    The purity and fidelity of quantum operations are of great importance in characterizing the quality of quantum operations. The currently available definitions of the purity and fidelity of quantum operations are based on the average over all possible input pure quantum states, i.e. they are state-dependent (SD). In this paper, without resorting to quantum states, we define the state-independent (SI) purity and fidelity of a general quantum operation (evolution) in virtue of a new density matrix formalism for quantum operations, which is extended from the quantum state level to quantum operation level. The SI purity and fidelity gain more intrinsic physical properties of quantum operations than state-dependent ones, such as the purity of a one-qubit amplitude damping channel (with damping rate 1) is 1/2, which is in line with the fact that the channel is still a nonunitary operation described by two Kraus operators rather than a unitary one. But the state-dependent Haar average purity is 1 in this case. So the SI purity and fidelity proposed here can help the experimentalists to exactly quantify the implementation quality of an operation. As a byproduct, a new measure of the operator entanglement is proposed for a quantum evolution (unitary or nonunitary) in terms of the linear entropy of its density matrix on the orthonormal operator bases (OOBs) in Hilbert-Schmidt space.

  17. Production of High Purity Niobium Ingots at CBMM

    SciTech Connect

    Moura, Lourenco de; Faria Sousa, Clovis Antonio de; Burgos Cruz, Edmundo

    2011-03-31

    CBMM is a fully integrated company, from the mine to the end line of the production chain, supplying different niobium products to the world market: ferroniobium, nickelniobium, niobium pentoxide and high purity metallic niobium. This high purity metallic niobium has long been known to exhibit superconductivity below 9.25 Kelvin. This characteristic has the potential to bring technological benefits for many different areas such as medicine, computing and environment. This paper presents the raw material requirements as well as CBMM experience on producing high purity niobium ingots. The results prove that CBMM material can be the best solution for special applications such as low cost superconductive radiofrequency cavities.

  18. Production of High Purity Niobium Ingots at CBMM

    NASA Astrophysics Data System (ADS)

    de Moura, Lourenço; de Faria Sousa, Clovis Antonio; Cruz, Edmundo Burgos

    2011-03-01

    CBMM is a fully integrated company, from the mine to the end line of the production chain, supplying different niobium products to the world market: ferroniobium, nickelniobium, niobium pentoxide and high purity metallic niobium. This high purity metallic niobium has long been known to exhibit superconductivity below 9.25 Kelvin. This characteristic has the potential to bring technological benefits for many different areas such as medicine, computing and environment. This paper presents the raw material requirements as well as CBMM experience on producing high purity niobium ingots. The results prove that CBMM material can be the best solution for special applications such as low cost superconductive radiofrequency cavities.

  19. Heat capacity of high-purity isotope-enriched germanium-76 in the temperature range of 2-15 K

    NASA Astrophysics Data System (ADS)

    Gusev, A. V.; Gibin, A. M.; Andryushchenko, I. A.; Gavva, V. A.; Kozyrev, E. A.

    2015-09-01

    The heat capacity of high-purity isotopically-enriched germanium Ge-76 has been measured in the range of 2.5-15 K. In this range, the heat capacity of Ge-76 is 6-15% higher than the heat capacity of germanium of the natural isotopic composition, which is determined by a change in the average mass.

  20. Optimizing Bacillus subtilis spore isolation and quantifying spore harvest purity.

    PubMed

    Harrold, Zoë R; Hertel, Mikaela R; Gorman-Lewis, Drew

    2011-12-01

    Investigating the biochemistry, resilience and environmental interactions of bacterial endospores often requires a pure endospore biomass free of vegetative cells. Numerous endospore isolation methods, however, neglect to quantify the purity of the final endospore biomass. To ensure low vegetative cell contamination we developed a quality control technique that enables rapid quantification of endospore harvest purity. This method quantifies spore purity using bright-field and fluorescence microscopy imaging in conjunction with automated cell counting software. We applied this method to Bacillus subtilis endospore harvests isolated using a two-phase separation method that utilizes mild chemicals. The average spore purity of twenty-two harvests was 88±11% (error is 1σ) with a median value of 93%. A spearman coefficient of 0.97 correlating automated and manual bacterial counts confirms the accuracy of software generated data.

  1. 1. LOOKING SOUTH AT LOW PURITY BULK OXYGEN BUILDING (FORMERLY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. LOOKING SOUTH AT LOW PURITY BULK OXYGEN BUILDING (FORMERLY BLOW ENGINE HOUSE No. 1), WITH LIQUID OXYGEN STORAGE TANKS IN THE FOREGROUND. - U.S. Steel Duquesne Works, Fuel & Utilities Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  2. Method to obtain C-phycocyanin of high purity.

    PubMed

    Patil, Ganapathi; Chethana, S; Sridevi, A S; Raghavarao, K S M S

    2006-09-15

    A new approach is made for the purification of C-phycocyanin (C-PC), which is simple and more efficient than existing methods. The proposed method involves two steps: aqueous two phase extraction and ion-exchange chromatography. Crude extract of C-phycocyanin, of purity 1.18, obtained from Spirulina platensis is subjected to aqueous two phase extraction. C-phycocyanin obtained from this process showed a purity of 5.22, which is higher than the reported value till date. In order to explore the possibility of further purification, C-phycocyanin is subjected to ion-exchange chromatography and found that the purity increased from 5.22 to 6.69. The fluorescence, intactness of structure and purity of C-phycocyanin are confirmed using spectrofluorometry, circular dichroism spectra and sodium dodecyl sulfate-polyacrylamide gel, respectively.

  3. Systematic pan-cancer analysis of tumour purity.

    PubMed

    Aran, Dvir; Sirota, Marina; Butte, Atul J

    2015-12-04

    The tumour microenvironment is the non-cancerous cells present in and around a tumour, including mainly immune cells, but also fibroblasts and cells that comprise supporting blood vessels. These non-cancerous components of the tumour may play an important role in cancer biology. They also have a strong influence on the genomic analysis of tumour samples, and may alter the biological interpretation of results. Here we present a systematic analysis using different measurement modalities of tumour purity in >10,000 samples across 21 cancer types from the Cancer Genome Atlas. Patients are stratified according to clinical features in an attempt to detect clinical differences driven by purity levels. We demonstrate the confounding effect of tumour purity on correlating and clustering tumours with transcriptomics data. Finally, using a differential expression method that accounts for tumour purity, we find an immunotherapy gene signature in several cancer types that is not detected by traditional differential expression analyses.

  4. Determination of Purity by Differential Scanning Calorimetry (DSC).

    ERIC Educational Resources Information Center

    Brown, M. E.

    1979-01-01

    An exercise is presented which demonstrates the determination of sample purity by differential scanning calorimetry. Data and references are provided to enable the exercise to be carried out as a dry-lab experiment. (BB)

  5. 2. WESTWARD VIEW OF LOW PURITY BULK OXYGEN BUILDING, AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. WESTWARD VIEW OF LOW PURITY BULK OXYGEN BUILDING, AND FERROMANGANESE GAS CLEANING PLANT ON LEFT. - U.S. Steel Duquesne Works, Fuel & Utilities Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  6. Computational approach to quantum encoder design for purity optimization

    SciTech Connect

    Yamamoto, Naoki; Fazel, Maryam

    2007-07-15

    In this paper, we address the problem of designing a quantum encoder that maximizes the minimum output purity of a given decohering channel, where the minimum is taken over all possible pure inputs. This problem is cast as a max-min optimization problem with a rank constraint on an appropriately defined matrix variable. The problem is computationally very hard because it is nonconvex with respect to both the objective function (output purity) and the rank constraint. Despite this difficulty, we provide a tractable computational algorithm that produces the exact optimal solution for codespace of dimension 2. Moreover, this algorithm is easily extended to cover the general class of codespaces, in which case the solution is suboptimal in the sense that the suboptimized output purity serves as a lower bound of the exact optimal purity. The algorithm consists of a sequence of semidefinite programmings and can be performed easily. Two typical quantum error channels are investigated to illustrate the effectiveness of our method.

  7. Determination of Purity by Differential Scanning Calorimetry (DSC).

    ERIC Educational Resources Information Center

    Brown, M. E.

    1979-01-01

    An exercise is presented which demonstrates the determination of sample purity by differential scanning calorimetry. Data and references are provided to enable the exercise to be carried out as a dry-lab experiment. (BB)

  8. An algebraic function operator expectation value based eigenstate determinations for quantum systems with one degree of freedom

    SciTech Connect

    Kalay, Berfin; Demiralp, Metin

    2015-12-31

    This proceedings paper aims to show the efficiency of an expectation value identity for a given algebraic function operator which is assumed to be depending pn only position operator. We show that this expectation value formula becomes enabled to determine the eigenstates of the quantum system Hamiltonian as long as it is autonomous and an appropriate basis set in position operator is used. This approach produces a denumerable infinite recursion which may be considered as revisited but at the same time generalized form of the recursions over the natural number powers of the position operator. The content of this short paper is devoted not only to the formulation of the new method but also to show that this novel approach is capable of catching the eigenvalues and eigenfunctions for Hydrogen-like systems, beyond that, it can give a hand to us to reveal the wavefunction structure. So it has also somehow a confirmative nature.

  9. The eigenstate thermalization hypothesis in constrained Hilbert spaces: A case study in non-Abelian anyon chains

    NASA Astrophysics Data System (ADS)

    Chandran, A.; Schulz, Marc D.; Burnell, F. J.

    2016-12-01

    Many phases of matter, including superconductors, fractional quantum Hall fluids, and spin liquids, are described by gauge theories with constrained Hilbert spaces. However, thermalization and the applicability of quantum statistical mechanics has primarily been studied in unconstrained Hilbert spaces. In this paper, we investigate whether constrained Hilbert spaces permit local thermalization. Specifically, we explore whether the eigenstate thermalization hypothesis (ETH) holds in a pinned Fibonacci anyon chain, which serves as a representative case study. We first establish that the constrained Hilbert space admits a notion of locality by showing that the influence of a measurement decays exponentially in space. This suggests that the constraints are no impediment to thermalization. We then provide numerical evidence that ETH holds for the diagonal and off-diagonal matrix elements of various local observables in a generic disorder-free nonintegrable model. We also find that certain nonlocal observables obey ETH.

  10. Magnetoelectric subbands and eigenstates in the presence of Rashba and Dresselhaus spin-orbit interactions in a quantum wire

    NASA Astrophysics Data System (ADS)

    Bandyopadhyay, S.; Pramanik, S.; Cahay, M.

    2004-01-01

    We derive the eigenenergies and spin-dependent eigenstates of electrons in a quantum wire subjected to an external magnetic field. These are calculated in the presence of spin-orbit interactions arising from the Rashba (structural inversion asymmetry) and Dresselhaus (bulk inversion asymmetry) effects. We consider three cases: the external magnetic field is oriented (i) along the axis of the wire, (ii) perpendicular to the axis but parallel to the electric field associated with structural inversion asymmetry (Rashba effect), and (iii) perpendicular to the axis as well as this electric field. In all cases, the dispersions of the eigenenergies are non-parabolic and the subbands do not have a fixed spin quantization axis (meaning that the spin polarization of the electron is wavevector dependent). Except in the second case, the dispersion diagrams are also, in general, asymmetric about the energy axis.

  11. Unification of perturbation theory, random matrix theory, and semiclassical considerations in the study of parametrically dependent eigenstates

    PubMed

    Cohen; Heller

    2000-03-27

    We consider a classically chaotic system that is described by a Hamiltonian H(Q,P;x), where x is a constant parameter. Specifically, we discuss a gas particle inside a cavity, where x controls a deformation of the boundary or the position of a "piston." The quantum eigenstates of the system are |n(x)>. We describe how the parametric kernel P(nmid R:m) = ||(2) evolves as a function of deltax = x-x(0). We explore both the perturbative and the nonperturbative regimes, and discuss the capabilities and the limitations of semiclassical as well as random waves and random-matrix-theory considerations.

  12. Delta Doping High Purity CCDs and CMOS for LSST

    NASA Technical Reports Server (NTRS)

    Blacksberg, Jordana; Nikzad, Shouleh; Hoenk, Michael; Elliott, S. Tom; Bebek, Chris; Holland, Steve; Kolbe, Bill

    2006-01-01

    A viewgraph presentation describing delta doping high purity CCD's and CMOS for LSST is shown. The topics include: 1) Overview of JPL s versatile back-surface process for CCDs and CMOS; 2) Application to SNAP and ORION missions; 3) Delta doping as a back-surface electrode for fully depleted LBNL CCDs; 4) Delta doping high purity CCDs for SNAP and ORION; 5) JPL CMP thinning process development; and 6) Antireflection coating process development.

  13. Delta Doping High Purity CCDs and CMOS for LSST

    NASA Technical Reports Server (NTRS)

    Blacksberg, Jordana; Nikzad, Shouleh; Hoenk, Michael; Elliott, S. Tom; Bebek, Chris; Holland, Steve; Kolbe, Bill

    2006-01-01

    A viewgraph presentation describing delta doping high purity CCD's and CMOS for LSST is shown. The topics include: 1) Overview of JPL s versatile back-surface process for CCDs and CMOS; 2) Application to SNAP and ORION missions; 3) Delta doping as a back-surface electrode for fully depleted LBNL CCDs; 4) Delta doping high purity CCDs for SNAP and ORION; 5) JPL CMP thinning process development; and 6) Antireflection coating process development.

  14. A TNFR2-Agonist Facilitates High Purity Expansion of Human Low Purity Treg Cells.

    PubMed

    He, Xuehui; Landman, Sija; Bauland, Stijn C G; van den Dolder, Juliette; Koenen, Hans J P M; Joosten, Irma

    2016-01-01

    Regulatory T cells (Treg) are important for immune homeostasis and are considered of great interest for immunotherapy. The paucity of Treg numbers requires the need for ex vivo expansion. Although therapeutic Treg flow-sorting is feasible, most centers aiming at Treg-based therapy focus on magnetic bead isolation of CD4+CD25+ Treg using a good manufacturing practice compliant closed system that achieves lower levels of cell purity. Polyclonal Treg expansion protocols commonly use anti-CD3 plus anti-CD28 monoclonal antibody (mAb) stimulation in the presence of rhIL-2, with or without rapamycin. However, the resultant Treg population is often heterogeneous and pro-inflammatory cytokines like IFNγ and IL-17A can be produced. Hence, it is crucial to search for expansion protocols that not only maximize ex vivo Treg proliferative rates, but also maintain Treg stability and preserve their suppressive function. Here, we show that ex vivo expansion of low purity magnetic bead isolated Treg in the presence of a TNFR2 agonist mAb (TNFR2-agonist) together with rapamycin, results in a homogenous stable suppressive Treg population that expresses FOXP3 and Helios, shows low expression of CD127 and hypo-methylation of the FOXP3 gene. These cells reveal a low IL-17A and IFNγ producing potential and hardly express the chemokine receptors CCR6, CCR7 and CXCR3. Restimulation of cells in a pro-inflammatory environment did not break the stability of this Treg population. In a preclinical humanized mouse model, the TNFR2-agonist plus rapamycin expanded Treg suppressed inflammation in vivo. Importantly, this Treg expansion protocol enables the use of less pure, but more easily obtainable cell fractions, as similar outcomes were observed using either FACS-sorted or MACS-isolated Treg. Therefore, this protocol is of great interest for the ex vivo expansion of Treg for clinical immunotherapy.

  15. Importance of purity evaluation and the potential of quantitative ¹H NMR as a purity assay.

    PubMed

    Pauli, Guido F; Chen, Shao-Nong; Simmler, Charlotte; Lankin, David C; Gödecke, Tanja; Jaki, Birgit U; Friesen, J Brent; McAlpine, James B; Napolitano, José G

    2014-11-26

    In any biomedical and chemical context, a truthful description of chemical constitution requires coverage of both structure and purity. This qualification affects all drug molecules, regardless of development stage (early discovery to approved drug) and source (natural product or synthetic). Purity assessment is particularly critical in discovery programs and whenever chemistry is linked with biological and/or therapeutic outcome. Compared with chromatography and elemental analysis, quantitative NMR (qNMR) uses nearly universal detection and provides a versatile and orthogonal means of purity evaluation. Absolute qNMR with flexible calibration captures analytes that frequently escape detection (water, sorbents). Widely accepted structural NMR workflows require minimal or no adjustments to become practical ¹H qNMR (qHNMR) procedures with simultaneous qualitative and (absolute) quantitative capability. This study reviews underlying concepts, provides a framework for standard qHNMR purity assays, and shows how adequate accuracy and precision are achieved for the intended use of the material.

  16. Electric-dipole-coupled H2O@C60 dimer: Translation-rotation eigenstates from twelve-dimensional quantum calculations

    NASA Astrophysics Data System (ADS)

    Felker, Peter M.; Bačić, Zlatko

    2017-02-01

    We report on variational solutions to the twelve-dimensional (12D) Schrödinger equation appertaining to the translation-rotation (TR) eigenstates of H2O@C60 dimer, associated with the quantized "rattling" motions of the two encapsulated H2O molecules. Both H2O and C60 moieties are treated as rigid and the cage-cage geometry is taken to be fixed. We consider the TR eigenstates of H2O@C60 monomers in the dimer to be coupled by the electric dipole-dipole interaction between water moieties and develop expressions for computing the matrix elements of that interaction in a dimer basis composed of products of monomer 6D TR eigenstates reported by us recently [P. M. Felker and Z. Bačić, J. Chem. Phys. 144, 201101 (2016)]. We use these expressions to compute TR Hamiltonian matrices of H2O@C60 dimer for two values of the water dipole moment and for various dimer geometries. 12D TR eigenstates of the dimer are then obtained by filter diagonalization. The results reveal two classes of eigenstates, distinguished by the leading order (first or second) at which dipole-dipole coupling contributes to them. The two types of eigenstates differ in the general magnitude of their dipole-induced energy shifts and in the dependence of those shifts on the value of the water dipole moment and on the distance between the H2O@C60 monomers. The dimer results are also found to be markedly insensitive to any change in the orientations of the C60 cages. Finally, the results lend some support for the interpretation that electric dipole-dipole coupling is at least partially responsible for the apparent reduced-symmetry environment experienced by H2O in the powder samples of H2O@C60 [K. S. K. Goh et al., Phys. Chem. Chem. Phys. 16, 21330 (2014)], but only if the water dipole is taken to have a magnitude close to that of free water. The methodology developed in the paper is transferable directly to the calculation of TR eigenstates of larger H2O@C60 assemblies, that will be required for more

  17. Composition, purity and perceived quality of street cocaine in France.

    PubMed

    Evrard, Isabelle; Legleye, Stéphane; Cadet-Taïrou, Agnès

    2010-09-01

    There is little knowledge about the composition and cocaine content of street cocaine, nor about what users know about it. 373 cocaine users were face to face interviewed between May and December 2006 about the last sample of cocaine they had consumed and residual amounts of the substances actually used were analysed using gas phase chromatography coupled to mass spectrometry (GC-MS). Users rated the perceived quality of their product ("good", "average", "poor"), its "estimated percentage of cocaine" and any cutting agents it contained. Price, quantity, place of purchase (street, dealer's premise, appointment), mode of administration (sniffing, injection, smoking) and the supposed nature of the sample (natural, synthetic, no distinction ever made) were also reported. Perceived quality was modelled using multivariate multinomial regression. The median cocaine content was 22%. Altogether, 343 samples contained cocaine, among which 75% contained at least one adulterant. The most frequently occurring were phenacetin (54% of the samples), caffeine (17%), paracetamol (14%), diltiazem and lidocaïne (11%). Users showed relatively poor discrimination concerning cocaine purity, and only 12% reported at least one of the detected adulterants. The major determinants of their perception of cocaine quality were: place of purchase, natural origin, price per gram, actual cocaine content and mode of administration. The composition of street cocaine is largely unknown to users. Users' perceptions of cocaine quality are based partly on false beliefs and certain administration modes. This may contribute to favouring very risky practices. The effects of adulterants on users' health should be investigated. Copyright 2010 Elsevier B.V. All rights reserved.

  18. Purity assessment of ginsenoside Rg1 using quantitative (1)H nuclear magnetic resonance.

    PubMed

    Huang, Bao-Ming; Xiao, Sheng-Yuan; Chen, Ting-Bo; Xie, Ying; Luo, Pei; Liu, Liang; Zhou, Hua

    2017-05-30

    Ginseng herbs comprise a group of the most popular herbs, including Panax ginseng, P. notoginseng and P. quinquefolius (Family Araliaceae), which are used as traditional Chinese medicine (TCM) and are some of the best-selling natural products in the world. The accurate quantification of ginsenoside Rg1 is one of the major aspects of its quality control. However, the purity of the commercial Rg1 chemical reference substance (CRS) is often measured with high-performance chromatography coupled with an ultraviolet detector (HPLC-UV), which is a selective detector with unequal responses to different compounds; thus, this detector introduces probable error to purity assessments. In the present study, quantitative nuclear magnetic resonance (qNMR), due to its absolute quantification ability, was applied to accurately assess the purity of Rg1 CRS. Phenylmethyl phthalate was used as the internal standard (IS) to calibrate the purity of Rg1 CRS. The proton signal of Rg1 CRS in methanol-d4 at 4.37ppm was selected to avoid interfering signals, enabling accurate quantitative analysis. The relaxation delay, number of scans, and NMR windowing were optimized for data acquisition. For post-processing, the Lorentz/Gauss deconvolution method was employed to increase the signal accuracy by separating the impurities and noise in the integrated region of the quantitative proton. The method validation showed that the developed method has acceptable sensitivity, linearity, precision, and accuracy. The purity of the commercial Rg1 CRS examined with the method developed in this research was 90.34±0.21%, which was obviously lower than that reported by the manufacturer (>98.0%, HPLC-UV). The cross-method validation shows that the commonly used HPLC-UV, HPLC-ELSD (evaporative light scattering detector) and even LC-MS (mass spectrometry) methods provide significantly higher purity values of Rg1 CRS compared with the qNMR method, and the accuracy of these LC-based methods largely depend on the

  19. Group-based discrimination in judgments of moral purity-related behaviors: experimental and archival evidence.

    PubMed

    Masicampo, E J; Barth, Maria; Ambady, Nalini

    2014-12-01

    Knowledge of individuals' group membership can alter moral judgments of their behavior. We found that such moral judgments were amplified when judgers learned that a person belonged to a group shown to elicit disgust in others. When a person was labeled as obese, a hippie, or "trailer trash," people judged that person's behavior differently than when such descriptors were omitted: Virtuous behaviors were more highly praised, and moral violations were more severely criticized. Such group-based discrimination in moral judgment was specific to the domain of moral purity. Members of disgust-eliciting groups but not members of other minorities were the target of harsh judgments for purity violations (e.g., lewd behavior) but not for other violations (e.g., refusing to help others). The same pattern held true for virtuous behaviors, so that members of disgust-eliciting groups were more highly praised than others but only in the purity domain. Furthermore, group-based discrimination was mediated by feelings of disgust toward the target group but not by other emotions. Last, analysis of New York Police Department officers' encounters with suspected criminals revealed a similar pattern to that found in laboratory experiments. Police officers were increasingly likely to make an arrest or issue a summons as body mass index increased (i.e., as obesity rose) among people suspected of purity crimes (e.g., prostitution) but not of other crimes (e.g., burglary). Thus, moral judgments in the lab and in the real world exhibit patterns of discrimination that are both group and behavior specific. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  20. Extinction coefficients and purity of single-walled carbon nanotubes.

    PubMed

    Zhao, B; Itkis, M E; Niyogi, S; Hu, H; Perea, D E; Haddon, R C

    2004-11-01

    Single-walled carbon nanotubes (SWNTs) hold great promise for advanced applications in aerospace, electronics and medicine, yet these industries require materials with rigorous quality control. There are currently no accepted standards for quality assurance or quality control among the commercial suppliers of SWNTs. We briefly discuss the applicability of various techniques to measure SWNT purity and review, in detail, the advantages of near infrared (NIR) spectroscopy for the quantitative assessment of the bulk carbonaceous purity of SWNTs. We review the use of solution phase NIR spectroscopy for the analysis and characterization of a variety of carbon materials, emphasizing SWNTs produced by the electric arc (EA), laser oven (LO) and HiPco (HC) methods. We consider the applicability of Beer's law to carbon materials dispersed in dimethylformamide (DMF) and the effective extinction coefficients that are obtained from such dispersions. Analysis of the areal absorptivities of the second interband transition of semiconducting EA-produced SWNTs for a number of samples of differing purities has lead to an absolute molar extinction coefficient for the carbonaceous impurities in EA-produced SWNT samples. We conclude that NIR spectroscopy is the clear method of choice for the assessment of the bulk carbonaceous purity of EA-produced SWNTs, and we suggest that an absolute determination of the purity of SWNTs is within reach. Continued work in this area is expected to lead to a universal method for the assessment of the absolute bulk purity of SWNTs from all sources--such a development will be of great importance for nanotube science and for future customers for this product.

  1. Compensation Mechanism in High Purity Semi-Insulating 4H-SiC

    DTIC Science & Technology

    2007-01-01

    online 15 March 2007 A study of deep levels in high purity semi-insulating 4H-SiC has been made using temperature dependent Hall effect TDH , thermal and...optical admittance spectroscopies, and secondary ion mass spectrometry SIMS. Thermal activation energies from TDH varied from a low of 0.55 eV to a...high of 1.65 eV. All samples studied showed n-type conduction with the Fermi level in the upper half of the band gap. Fits of the TDH data to

  2. Manufacture of high purity metal fluorides

    SciTech Connect

    Vance, J.M.

    1984-01-01

    The Oak Ridge Gaseous Diffusion Plant has been developing technologies of many kinds since the early forties. The primary purpose of this R and D was to reduce the amount of electrical power and capital expense associated with the enrichment of uranium in the 235 isotope. One area that has received a lot of attention is the chemistry of fluorine and metal fluorides. The producing facility at ORGDP is a chemical pilot plant which has been used through the years to demonstrate new processes. Presently existing in this facility are: absorption columns which have been used to remove trace quantities of krypton and oxides of nitrogen and sulfur from gas streams; a flame reactor that is being used to reduce isotopically altered sulfur hexafluoride for conversion to SO/sub 2/ which will be used in acid rain studies; an environmental hold system in which methods were developed to remove or neutralize environmental insulting compounds; a fluid bed reactor, and of course the tungsten hexafluoride process. A rhenium hexafluoride facility is also located in the pilot plant. It is basically the same as the tungsten line with three small muffles being used in place of the large WF6 reactor. The product from each process is heated and transferred to approved 5-inch shipping cylinders and transported to the analytical chemistry laboratory for sampling and analysis. These cylinders must be used for shipment and may require modification of the customer facility to accommodate them. Liquid samples are obtained from the product cylinders and a visual examination of the samples for color and melting temperature provides a good indication of the conversion. X-ray fluorescence is utilized to determine the amount of tungsten and the percent conversion to the hexafluoride is calculated from the weighed sample. Infrared in addition to mass spectrometer analyses are performed to verify the findings. The material is then analyzed by spectrographic methods for contaminants.

  3. Luminescence and photoconductivity of high-purity cadmium selenide

    SciTech Connect

    Martynov, V.N.

    1995-10-01

    Slightly off-stoichlometric high-purity cadmium and zinc chalcogenides are used as high-efficiency sensors in various optoelectronic devices. The procedure for preparing high-purity chalcogenides was described elsewhere. Such materials (wurtzite-type structure, sp. gr. C{sup 4}{sub 6v}) exhibit exciton luminescence and the photoconductivity associated with the A-, B-, and C-excitonic series over a wide temperature range. In this work, we studied the luminescence and photoconductivity (PC) of cadmium selenide prepared as described.

  4. Multifractality of eigenstates in the delocalized non-ergodic phase of some random matrix models: Wigner-Weisskopf approach

    NASA Astrophysics Data System (ADS)

    Monthus, Cécile

    2017-07-01

    The delocalized non-ergodic phase existing in some random N × N matrix models is analyzed via the Wigner-Weisskopf approximation for the dynamics from an initial site j 0. The main output of this approach is the inverse Γj_0(N) of the characteristic time to leave the state j 0 that provides some broadening Γj_0(N) for the weights of the eigenvectors. In this framework, the localized phase corresponds to the region where the broadening Γj_0(N) is smaller in scaling than the level spacing Δj_0(N) \\propto \\frac{1}{N} , while the delocalized non-ergodic phase corresponds to the region where the broadening Γj_0(N) decays with N but is bigger in scaling than the level spacing Δj_0(N) . Then the number \\fracΓj_0(N)}{Δj_0(N)} of resonances grows only sub-extensively in N. This approach allows to recover the multifractal spectrum of the Generalized-Rosenzweig-Potter (GRP) Matrix model (Kravtsov et al 2015 New. J. Phys. 17 122 002). We then consider the Lévy generalization of the GRP Matrix model, where the off-diagonal matrix elements are drawn with an heavy-tailed distribution of Lévy index 1<μ<2 : the dynamics is then governed by a stretched exponential of exponent β=\\frac{2 (μ-1)}{μ and the multifractal properties of eigenstates are explicitly computed.

  5. Strengthening Purity: Moral Purity as a Mediator of Direct and Extended Cross-Group Friendships on Sexual Prejudice.

    PubMed

    Vezzali, Loris; Brambilla, Marco; Giovannini, Dino; Paolo Colucci, Francesco

    2017-01-01

    The present research investigated whether enhanced perceptions of moral purity drive the effects of intergroup cross-group friendships on the intentions to interact with homosexuals. High-school students (N = 639) reported their direct and extended cross-group friendships with homosexuals as well as their beliefs regarding the moral character of the sexual minority. Participants further reported their desire to interact with homosexuals in the future. Results showed that both face-to-face encounters and extended contact with homosexuals increased their perceived moral purity, which in turn fostered more positive behavioral intentions. Results further revealed the specific role of moral purity in this sense, as differential perceptions along other moral domains (autonomy and community) had no mediation effects on behavioral tendencies toward homosexuals. The importance of these findings for improving intergroup relations is discussed, together with the importance of integrating research on intergroup contact and morality.

  6. Evaluation of purity with its uncertainty value in high purity lead stick by conventional and electro-gravimetric methods.

    PubMed

    Singh, Nahar; Singh, Niranjan; Tripathy, S Swarupa; Soni, Daya; Singh, Khem; Gupta, Prabhat K

    2013-06-26

    A conventional gravimetry and electro-gravimetry study has been carried out for the precise and accurate purity determination of lead (Pb) in high purity lead stick and for preparation of reference standard. Reference materials are standards containing a known amount of an analyte and provide a reference value to determine unknown concentrations or to calibrate analytical instruments. A stock solution of approximate 2 kg has been prepared after dissolving approximate 2 g of Pb stick in 5% ultra pure nitric acid. From the stock solution five replicates of approximate 50 g have been taken for determination of purity by each method. The Pb has been determined as PbSO4 by conventional gravimetry, as PbO2 by electro gravimetry. The percentage purity of the metallic Pb was calculated accordingly from PbSO4 and PbO2. On the basis of experimental observations it has been concluded that by conventional gravimetry and electro-gravimetry the purity of Pb was found to be 99.98 ± 0.24 and 99.97 ± 0.27 g/100 g and on the basis of Pb purity the concentration of reference standard solutions were found to be 1000.88 ± 2.44 and 1000.81 ± 2.68 mg kg-1 respectively with 95% confidence level (k = 2). The uncertainty evaluation has also been carried out in Pb determination following EURACHEM/GUM guidelines. The final analytical results quantifying uncertainty fulfills this requirement and gives a measure of the confidence level of the concerned laboratory. Gravimetry is the most reliable technique in comparison to titremetry and instrumental method and the results of gravimetry are directly traceable to SI unit. Gravimetric analysis, if methods are followed carefully, provides for exceedingly precise analysis. In classical gravimetry the major uncertainties are due to repeatability but in electro-gravimetry several other factors also affect the final results.

  7. Evaluation of purity with its uncertainty value in high purity lead stick by conventional and electro-gravimetric methods

    PubMed Central

    2013-01-01

    Background A conventional gravimetry and electro-gravimetry study has been carried out for the precise and accurate purity determination of lead (Pb) in high purity lead stick and for preparation of reference standard. Reference materials are standards containing a known amount of an analyte and provide a reference value to determine unknown concentrations or to calibrate analytical instruments. A stock solution of approximate 2 kg has been prepared after dissolving approximate 2 g of Pb stick in 5% ultra pure nitric acid. From the stock solution five replicates of approximate 50 g have been taken for determination of purity by each method. The Pb has been determined as PbSO4 by conventional gravimetry, as PbO2 by electro gravimetry. The percentage purity of the metallic Pb was calculated accordingly from PbSO4 and PbO2. Results On the basis of experimental observations it has been concluded that by conventional gravimetry and electro-gravimetry the purity of Pb was found to be 99.98 ± 0.24 and 99.97 ± 0.27 g/100 g and on the basis of Pb purity the concentration of reference standard solutions were found to be 1000.88 ± 2.44 and 1000.81 ± 2.68 mg kg-1 respectively with 95% confidence level (k = 2). The uncertainty evaluation has also been carried out in Pb determination following EURACHEM/GUM guidelines. The final analytical results quantifying uncertainty fulfills this requirement and gives a measure of the confidence level of the concerned laboratory. Conclusions Gravimetry is the most reliable technique in comparison to titremetry and instrumental method and the results of gravimetry are directly traceable to SI unit. Gravimetric analysis, if methods are followed carefully, provides for exceedingly precise analysis. In classical gravimetry the major uncertainties are due to repeatability but in electro-gravimetry several other factors also affect the final results. PMID:23800080

  8. Low cost routes to high purity silicon and derivatives thereof

    DOEpatents

    Laine, Richard M; Krug, David James; Marchal, Julien Claudius; Mccolm, Andrew Stewart

    2013-07-02

    The present invention is directed to a method for providing an agricultural waste product having amorphous silica, carbon, and impurities; extracting from the agricultural waste product an amount of the impurities; changing the ratio of carbon to silica; and reducing the silica to a high purity silicon (e.g., to photovoltaic silicon).

  9. Electrochemical study of aluminum corrosion in boiling high purity water

    NASA Technical Reports Server (NTRS)

    Draley, J. E.; Legault, R. A.

    1969-01-01

    Electrochemical study of aluminum corrosion in boiling high-purity water includes an equation relating current and electrochemical potential derived on the basis of a physical model of the corrosion process. The work involved an examination of the cathodic polarization behavior of 1100 aluminum during aqueous oxidation.

  10. Electrolytic production of high purity aluminum using ceramic inert anodes

    DOEpatents

    Ray, Siba P.; Liu, Xinghua; Weirauch, Douglas A.; DiMilia, Robert A.; Dynys, Joseph M.; Phelps, Frankie E.; LaCamera, Alfred F.

    2002-01-01

    A method of producing commercial purity aluminum in an electrolytic reduction cell comprising ceramic inert anodes is disclosed. The method produces aluminum having acceptable levels of Fe, Cu and Ni impurities. The ceramic inert anodes used in the process may comprise oxides containing Fe and Ni, as well as other oxides, metals and/or dopants.

  11. Electrolytic production of high purity aluminum using inert anodes

    DOEpatents

    Ray, Siba P.; Liu, Xinghua; Weirauch, Jr., Douglas A.

    2001-01-01

    A method of producing commercial purity aluminum in an electrolytic reduction cell comprising inert anodes is disclosed. The method produces aluminum having acceptable levels of Fe, Cu and Ni impurities. The inert anodes used in the process preferably comprise a cermet material comprising ceramic oxide phase portions and metal phase portions.

  12. Purity Evaluation of Bulk Single Wall Carbon Nanotube Materials

    NASA Astrophysics Data System (ADS)

    Dettlaff-Weglikowska, U.; Wang, J.; Liang, J.; Hornbostel, B.; Cech, J.; Roth, S.

    2005-09-01

    We report on our experience using a preliminary protocol for quality control of bulk single wall carbon nanotube (SWNT) materials produced by the electric arc-discharge and laser ablation method. The first step in the characterization of the bulk material is mechanical homogenization. Quantitative evaluation of purity has been performed using a previously reported procedure based on solution phase near-infrared spectroscopy. Our results confirm that this method is reliable in determining the nanotube content in the arc-discharge sample containing carbonaceous impurities (amorphous carbon and graphitic particles). However, the application of this method to laser ablation samples gives a relative purity value over 100 %. The possible reason for that might be different extinction coefficient meaning different oscillator strength of the laser ablation tubes. At the present time, a 100 % pure reference sample of laser ablation SWNT is not available, so we chose to adopt the sample showing the highest purity as a new reference sample for a quantitative purity evaluation of laser ablation materials. The graphitic part of the carbonaceous impurities has been estimated using X-ray diffraction of 1:1 mixture of nanotube material and C60 as an internal reference. To evaluate the metallic impurities in the as prepared and homogenized carbon nanotube soot inductive coupled plasma (ICP) has been used.

  13. Student Teachers' Concepts of Purity and of States of Matter.

    ERIC Educational Resources Information Center

    Ryan, Charly

    1990-01-01

    Described in this study are student teachers' frameworks of purity and the related concepts of the states of matter. The concept of natural versus pure substances, classifying states of matter, and implications for teaching drawn from the results are discussed. (Author/KR)

  14. Purity assessment of commercial zein products after purification

    USDA-ARS?s Scientific Manuscript database

    Successful utilization of commercial zein products for certain food, pharmaceutical, cosmetic and medical applications requires a decolorized/deodorized zein of high purity. A zein protein product with those qualifications can be achieved by column filtration of commercial yellow zein solutions thro...

  15. 7 CFR 201.7 - Purity (including variety).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Records for Agricultural and Vegetable Seeds § 201.7 Purity (including variety). The complete record for any lot of seed shall include (a) records of analyses, tests, and examinations including...

  16. 7 CFR 201.7 - Purity (including variety).

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Records for Agricultural and Vegetable Seeds § 201.7 Purity (including variety). The complete record for any lot of seed shall include (a) records of analyses, tests, and examinations including...

  17. 7 CFR 201.7 - Purity (including variety).

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Records for Agricultural and Vegetable Seeds § 201.7 Purity (including variety). The complete record for any lot of seed shall include (a) records of analyses, tests, and examinations including...

  18. 7 CFR 201.7 - Purity (including variety).

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Records for Agricultural and Vegetable Seeds § 201.7 Purity (including variety). The complete record for any lot of seed shall include (a) records of analyses, tests, and examinations including...

  19. 7 CFR 201.7 - Purity (including variety).

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Records for Agricultural and Vegetable Seeds § 201.7 Purity (including variety). The complete record for any lot of seed shall include (a) records of analyses, tests, and examinations including...

  20. High-Purity Nickel Prepared by Electron Beam Melting: Purification Mechanism

    NASA Astrophysics Data System (ADS)

    Zhang, Tao; Shang, Zaiyan; Chen, Ming; He, Jinjiang; Lv, Baoguo; Wang, Xingquan; Xiong, Xiaodong

    2013-12-01

    A bulk cylindrical high-purity nickel ingot, with purity of more than 99.999 pct (5N) in mass, was obtained from the raw nickel with 99.95 pct (3N5) initial purity by virtue of double electron beam melting (EBM). A chemical analysis was performed by using glow discharge mass spectrometry (GDMS) analysis for all elements in the periodic table except carbon, nitrogen, and oxygen, which were tested by the high-performance combustion and fusion method. The major impurities B, Na, Al, Si, P, S, Ca, Ti, Cr, Fe, Cu, Co, Zn, As, Ag, Sb, and Pb showed an excellent removal effect with removal efficiency of more than 85 pct following the double EBMs. Li, Mg, Cl, K, V, Mn, Ga, Ge, Cd, Se, In, Sn, Tl, Au, and Pt were below the detection limit. No significant change in concentration was found for the refractory elements W, Mo, Ta, Nb, and Ir. Be, F, Sc, Se, Br, Rb, Sr, Zr, Y, Ru, Rh, Pd, Te, I, Cs, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Re, Os, Hg, Bi, Th, and U were not detectable following the purification as compared to the raw nickel. Gaseous impurities, C, N, O, especially for N, was removed sufficiently. Theoretical calculations for removal efficiency of impurity Fe based on the calculated vapor pressure, activity coefficient, and melt temperature were in good agreement with measured results, and the purification mechanism was ascribed to the evaporation of major impurities and subsequently evacuation by repetitive EBM.

  1. Helicity eigenstates of a relativistic spin-0 and spin-1/2 constituent bound by minimal electrodynamics: Zero orbital angular momentum, zero four-momentum solutions

    NASA Astrophysics Data System (ADS)

    Mainland, G. Bruce

    1988-01-01

    Zero four-momentum, helicity eigenstates of the Bethe-Salpeter equation are found for a composite system consisting of a charged, spin-0 constituent and a charged, spin- 1/2 constituent bound by minimal electrodynamics. The form of the Bethe-Salpeter equation used to describe the bound state includes the contributions from both single photon exchange (ladder approximation) and the ``seagull'' diagram. Attention is restricted to zero orbital angular momentum states since these appear to be the most interesting physically.

  2. Helicity eigenstates of a relativistic spin-0 and spin-1/2 constituent bound by minimal electrodynamics: Zero orbital angular momentum, zero four-momentum solutions

    SciTech Connect

    Mainland, G.B.

    1988-01-01

    Zero four-momentum, helicity eigenstates of the Bethe--Salpeter equation are found for a composite system consisting of a charged, spin-0 constituent and a charged, spin- 1/2 constituent bound by minimal electrodynamics. The form of the Bethe--Salpeter equation used to describe the bound state includes the contributions from both single photon exchange (ladder approximation) and the ''seagull'' diagram. Attention is restricted to zero orbital angular momentum states since these appear to be the most interesting physically.

  3. Radiationless relaxation in “large” molecules: Experimental evidence for preparation of true molecular eigenstates and Born-Oppenheimer states by a coherent light source

    PubMed Central

    Zewail, A. H.; Orlowski, T. E.; Jones, K. E.

    1977-01-01

    Photon absorption and emission by molecules that undergo radiationless transitions are examined using the single modes of lasers having well-defined coherence properties. Contrary to the usual beliefs, where it is assumed that the molecule is prepared in a Born-Oppenheimer singlet state and then “crosses-over” to other states (vibrationally “hot” singlets and/or triplets), it is shown experimentally that the true eigenstates of the molecule can be prepared, even in “large” molecules, if the laser correlation time is relatively long and the molecular relaxation is made slow. On the other hand, lasers with short (psec) correlation time have yielded effectively the singlet Born-Oppenheimer state, which has a much shorter lifetime than the true eigenstates. Effects of magnetic fields and temperature are also reported. The former changes the amount of mixing amongst the Born-Oppenheimer states. The latter, on the other hand, swings the molecule from being “small” (i.e., sparse vibronic structure with long lifetimes) to being “large” (i.e., dense statistical distribution of levels) since the relaxation between levels is very effective at high temperatures. Finally, the results of this work show that the words fluorescence and phosphorescence in their strict meaning are misleading if the true eigenstates, which may contain both singlet and triplet character, are prepared. Images PMID:16578747

  4. Chemical purity using quantitative 1H-nuclear magnetic resonance: a hierarchical Bayesian approach for traceable calibrations

    NASA Astrophysics Data System (ADS)

    Toman, Blaza; Nelson, Michael A.; Lippa, Katrice A.

    2016-10-01

    Chemical purity assessment using quantitative 1H-nuclear magnetic resonance spectroscopy is a method based on ratio references of mass and signal intensity of the analyte species to that of chemical standards of known purity. As such, it is an example of a calculation using a known measurement equation with multiple inputs. Though multiple samples are often analyzed during purity evaluations in order to assess measurement repeatability, the uncertainty evaluation must also account for contributions from inputs to the measurement equation. Furthermore, there may be other uncertainty components inherent in the experimental design, such as independent implementation of multiple calibration standards. As such, the uncertainty evaluation is not purely bottom up (based on the measurement equation) or top down (based on the experimental design), but inherently contains elements of both. This hybrid form of uncertainty analysis is readily implemented with Bayesian statistical analysis. In this article we describe this type of analysis in detail and illustrate it using data from an evaluation of chemical purity and its uncertainty for a folic acid material.

  5. Chemical purity using quantitative (1)H-nuclear magnetic resonance: a hierarchical Bayesian approach for traceable calibrations.

    PubMed

    Toman, Blaza; Nelson, Michael A; Lippa, Katrice A

    2016-01-01

    Chemical purity assessment using quantitative (1)H-nuclear magnetic resonance spectroscopy is a method based on ratio references of mass and signal intensity of the analyte species to that of chemical standards of known purity. As such, it is an example of a calculation using a known measurement equation with multiple inputs. Though multiple samples are often analyzed during purity evaluations in order to assess measurement repeatability, the uncertainty evaluation must also account for contributions from inputs to the measurement equation. Furthermore, there may be other uncertainty components inherent in the experimental design, such as independent implementation of multiple calibration standards. As such, the uncertainty evaluation is not purely bottom up (based on the measurement equation) or top down (based on the experimental design), but inherently contains elements of both. This hybrid form of uncertainty analysis is readily implemented with Bayesian statistical analysis. In this article we describe this type of analysis in detail and illustrate it using data from an evaluation of chemical purity and its uncertainty for a folic acid material.

  6. Accurate calculation and assignment of highly excited vibrational levels of floppy triatomic molecules in a basis of adiabatic vibrational eigenstates

    NASA Astrophysics Data System (ADS)

    Bačić, Z.

    1991-09-01

    We show that the triatomic adiabatic vibrational eigenstates (AVES) provide a convenient basis for accurate discrete variable representation (DVR) calculation and automatic assignment of highly excited, large amplitude motion vibrational states of floppy triatomic molecules. The DVR-AVES states are eigenvectors of the diagonal (in the stretch states) blocks of the adiabatically rearranged triatomic DVR-ray eigenvector (DVR-REV) Hamiltonian [J. C. Light and Z. Bačić, J. Chem. Phys. 87, 4008 (1987)]. The transformation of the full triatomic vibrational Hamiltonian from the DVR-REV basis to the new DVR-AVES basis is simple, and does not involve calculation of any new matrix elements. No dynamical approximation is made in the energy level calculation by the DVR-AVES approach; its accuracy and efficiency are identical to those of the DVR-REV method. The DVR-AVES states, as the adiabatic approximation to the vibrational states of a triatomic molecule, are labeled by three vibrational quantum numbers. Consequently, accurate large amplitude motion vibrational levels obtained by diagonalizing the full vibrational Hamiltonian transformed to the DVR-AVES basis, can be assigned automatically by the code, with the three quantum numbers of the dominant DVR-AVES state associated with the largest (by modulus) eigenvector element in the DVR-AVES basis. The DVR-AVES approach is used to calculate accurate highly excited localized and delocalized vibrational levels of HCN/HNC and LiCN/LiNC. A significant fraction of localized states of both systems, below and above the isomerization barrier, is assigned automatically, without inspection of wave function plots or separate approximate calculations.

  7. Ambiguities and subtleties in fermion mass terms in practical quantum field theory

    NASA Astrophysics Data System (ADS)

    Cheng, Yifan; Kong, Otto C. W.

    2014-09-01

    This is a review on structure of the fermion mass terms in quantum field theory, under the perspective of its practical applications in the real physics of Nature-specifically, we discuss fermion mass structure in the Standard Model of high energy physics, which successfully describes fundamental physics up to the TeV scale. The review is meant to be pedagogical, with detailed mathematics presented beyond the level one can find any easily in the textbooks. The discussions, however, bring up important subtleties and ambiguities about the subject that may be less than well appreciated. In fact, the naive perspective of the nature and masses of fermions as one would easily drawn from the presentations of fermion fields and their equations of motion from a typical textbook on quantum field theory leads to some confusing or even wrong statements which we clarify here. In particular, we illustrate clearly that a Dirac fermion mass eigenstate is mathematically equivalent to two degenerated Majorana fermion mass eigenstates at least as long as the mass terms are concerned. There are further ambiguities and subtleties in the exact description of the eigenstate(s). Especially, for the case of neutrinos, the use of the Dirac or Majorana terminology may be mostly a matter of choice. The common usage of such terminology is rather based on the broken SU(2) charges of the related Weyl spinors hence conventional and may not be unambiguously extended to cover more complicate models.

  8. Qualification and initial characterization of a high-purity 233U spike for use in uranium analyses

    DOE PAGES

    Mathew, K. J.; Canaan, R. D.; Hexel, C.; ...

    2015-08-20

    Several high-purity 233U items potentially useful as isotope dilution mass spectrometry standards for safeguards, non-proliferation, and nuclear forensics measurements are identified and rescued from downblending. By preserving the supply of 233U materials of different pedigree for use as source materials for certified reference materials (CRMs), it is ensured that the safeguards community has high quality uranium isotopic standards required for calibration of the analytical instruments. One of the items identified as a source material for a high-purity CRM is characterized for the uranium isotope-amount ratios using thermal ionization mass spectrometry (TIMS). Additional verification measurements on this material using quadrupole inductivelymore » coupled plasma mass spectrometry (ICPMS) are also performed. As a result, the comparison of the ICPMS uranium isotope-amount ratios with the TIMS data, with much smaller uncertainties, validated the ICPMS measurement practices. ICPMS is proposed for the initial screening of the purity of items in the rescue campaign.« less

  9. Qualification and initial characterization of a high-purity 233U spike for use in uranium analyses

    SciTech Connect

    Mathew, K. J.; Canaan, R. D.; Hexel, C.; Giaquinto, J.; Krichinsky, A. M.

    2015-08-20

    Several high-purity 233U items potentially useful as isotope dilution mass spectrometry standards for safeguards, non-proliferation, and nuclear forensics measurements are identified and rescued from downblending. By preserving the supply of 233U materials of different pedigree for use as source materials for certified reference materials (CRMs), it is ensured that the safeguards community has high quality uranium isotopic standards required for calibration of the analytical instruments. One of the items identified as a source material for a high-purity CRM is characterized for the uranium isotope-amount ratios using thermal ionization mass spectrometry (TIMS). Additional verification measurements on this material using quadrupole inductively coupled plasma mass spectrometry (ICPMS) are also performed. As a result, the comparison of the ICPMS uranium isotope-amount ratios with the TIMS data, with much smaller uncertainties, validated the ICPMS measurement practices. ICPMS is proposed for the initial screening of the purity of items in the rescue campaign.

  10. Electrophoresis for the analysis of heparin purity and quality

    PubMed Central

    Volpi, Nicola; Maccari, Francesca; Suwan, Jiraporn; Linhardt, Robert J.

    2012-01-01

    The adulteration of raw heparin with oversulfated chondroitin sulfate (OSCS) in 2007–2008 produced a global crisis resulting in extensive revisions to the pharmacopeia monographs and prompting the FDA to recommend the development of additional methods for the analysis of heparin purity. As a consequence, a wide variety of innovative analytical approaches have been developed for the quality assurance and purity of unfractionated and low-molecular-weight heparins. This review discusses recent developments in electrophoresis techniques available for the sensitive separation, detection, and partial structural characterization of heparin contaminants. In particular, this review summarizes recent publications on heparin quality and related impurity analysis using electrophoretic separations such as capillary electrophoresis (CE) of intact polysaccharides and hexosamines derived from their acidic hydrolysis, and polyacrylamide gel electrophoresis (PAGE) for the separation of heparin samples without and in the presence of its relatively specific depolymerization process with nitrous acid treatment. PMID:22736353

  11. Electrophoresis for the analysis of heparin purity and quality.

    PubMed

    Volpi, Nicola; Maccari, Francesca; Suwan, Jiraporn; Linhardt, Robert J

    2012-06-01

    The adulteration of raw heparin with oversulfated chondroitin sulfate (OSCS) in 2007-2008 produced a global crisis resulting in extensive revisions to the pharmacopeia monographs and prompting the FDA to recommend the development of additional methods for the analysis of heparin purity. As a consequence, a wide variety of innovative analytical approaches have been developed for the quality assurance and purity of unfractionated and low-molecular-weight heparins. This review discusses recent developments in electrophoresis techniques available for the sensitive separation, detection, and partial structural characterization of heparin contaminants. In particular, this review summarizes recent publications on heparin quality and related impurity analysis using electrophoretic separations such as capillary electrophoresis (CE) of intact polysaccharides and hexosamines derived from their acidic hydrolysis, and polyacrylamide gel electrophoresis (PAGE) for the separation of heparin samples without and in the presence of its relatively specific depolymerization process with nitrous acid treatment.

  12. Synthesis of high phase purity ceramic oxide superconductors, xerogel method

    NASA Astrophysics Data System (ADS)

    Macho, J.; Schaeffer, R. W.; Myer, G. H.; Salomon, R. E.; Crow, J. E.

    Attention is given to xerogel precursors, which were prepared from a solution of yttrium, barium, and copper salts gelled by means of an organic gelling agent. The xerogel precursors were analyzed by X-ray diffraction, and the results show an amorphous structure which supports the existence of an atomic mixture of the metals. The optimal heat treatment of the xerogel precursor to yield the final product was determined by thermal gravimetric analysis. The results from X-ray diffractions of the YCBO superconductor show a phase purity higher than 99 percent. Conductivity and magnetic susceptibility tests on the product show Tc of 70 K before oxygen anneal and 92 K after annealing. The conductivity measurements further suggest the high phase purity of the material by the linear behavior of the resistivity vs temperature, which extrapolates to zero at 0 K. The particle size of the superconductor powders obtained from this method is less than one micron as studied by SEM.

  13. Tainting the soul: purity concerns predict moral judgments of suicide.

    PubMed

    Rottman, Joshua; Kelemen, Deborah; Young, Liane

    2014-02-01

    Moral violations are typically defined as actions that harm others. However, suicide is considered immoral even though the perpetrator is also the victim. To determine whether concerns about purity rather than harm predict moral condemnation of suicide, we presented American adults with obituaries describing suicide or homicide victims. While harm was the only variable predicting moral judgments of homicide, perceived harm (toward others, the self, or God) did not significantly account for variance in moral judgments of suicide. Instead, regardless of political and religious views and contrary to explicit beliefs about their own moral judgments, participants were more likely to morally condemn suicide if they (i) believed suicide tainted the victims' souls, (ii) reported greater concerns about purity in an independent questionnaire, (iii) experienced more disgust in response to the obituaries, or (iv) reported greater trait disgust. Thus, suicide is deemed immoral to the extent that it is considered impure. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. Characterization of low-purity clays for geopolymer binder formulation

    NASA Astrophysics Data System (ADS)

    Mostafa, Nasser Y.; Mohsen, Q.; El-maghraby, A.

    2014-06-01

    The production of geopolymer binders from low-purity clays was investigated. Three low-purity clays were calcined at 750°C for 4 h. The calcined clays were chemically activated by the alkaline solutions of NaOH and Na2SiO3. The compressive strength was measured as a function of curing time at room temperature and 85°C. The results were compared with those of a pure kaolin sample. An amorphous aluminosilicate polymer was formed in all binders at both processing temperatures. The results show that, the mechanical properties depend on the type and amount of active aluminum silicates in the starting clay material, the impurities, and the processing temperature.

  15. Internal friction measurement in high purity tungsten single crystal

    NASA Technical Reports Server (NTRS)

    Rieu, G. E.

    1974-01-01

    Internal friction peaks observed after small deformation in high purity tungsten single crystals between liquid helium temperature and 800 K in the frequency range 30-50 KHz, are studied as a function of orientation. An orientation effect is observed in the internal friction spectra due to the creation of internal stresses. The elementary processes related to these peaks are discussed in terms of kink generation and geometric kink motion on screw and edge dislocations in an internal stress field.

  16. High-Purity Silicon Seeds for Silane Pyrolysis

    NASA Technical Reports Server (NTRS)

    Hsu, G. C.; Rohatgi, N. K.; Morrison, A.

    1985-01-01

    Seed particles for fluidized-bed production of silicon made by new contamination-free, economical method. In new method, large particles of semiconductor-grade silicon fired at each other by high-speed streams of gas and thereby break up into particles of suitable size for fluidized bed. No foreign materials introduced, and leaching unnecessary. Method used to feed fluidized-bed reactor for continuous production of high-purity silicon.

  17. METHOD OF TESTING THERMAL NEUTRON FISSIONABLE MATERIAL FOR PURITY

    DOEpatents

    Fermi, E.; Anderson, H.L.

    1961-01-24

    A process is given for determining the neutronic purity of fissionable material by the so-called shotgun test. The effect of a standard neutron absorber of known characteristics and amounts on a neutronic field also of known characteristics is measured and compared with the effect which the impurities derived from a known quantity of fissionable material has on the same neutronic field. The two readings are then made the basis of calculation from which the amount of impurities can be computed.

  18. Dimensional stability of high-purity Invar 36

    NASA Astrophysics Data System (ADS)

    Sokolowski, Witold M.; Jacobs, Stephen F.; Lane, Marc S.; O'Donnell, Timothy P.; Hsieh, Cheng

    1993-12-01

    High performance requirements for the Imaging Science Subsystem/Narrow Angle Camera (NAC) instrument on the NASA/Jet Propulsion Laboratory (JPL) Cassini spacecraft impose very stringent demands for dimensional stability of metering rods in the camera's athermalizing system. Invar 36 was chosen as a baseline material because it possibly could meet these requirements through high purity control and appropriate thermomechanical processes. A powder metallurgy process appears to be the manufacturing method to ensure high purity and cleanliness of this material. Therefore, a powder metallurgy manufacturer was contacted and high purity (HP) Invar 36 was produced per JPL engineering requirements. Several heat treatments were established and heat treated HP Invar 36 samples were evaluated. Coefficient of thermal expansion (CTE), thermal hysteresis and temporal stability test results are reported here. The test results indicate that JPL has succeeded in obtaining possibly the most dimensionally stable (lowest CTE plus lowest temporal change) Invar 36 material ever produced. CTE < 1 ppm/ degree(s)C are reported here along with temporal stability < 1 ppm/year. These dimensional stability properties will meet the requirements for metering rods on the NAC.

  19. Ambiguities and subtleties in fermion mass terms in practical quantum field theory

    SciTech Connect

    Cheng, Yifan Kong, Otto C.W.

    2014-09-15

    This is a review on structure of the fermion mass terms in quantum field theory, under the perspective of its practical applications in the real physics of Nature—specifically, we discuss fermion mass structure in the Standard Model of high energy physics, which successfully describes fundamental physics up to the TeV scale. The review is meant to be pedagogical, with detailed mathematics presented beyond the level one can find any easily in the textbooks. The discussions, however, bring up important subtleties and ambiguities about the subject that may be less than well appreciated. In fact, the naive perspective of the nature and masses of fermions as one would easily drawn from the presentations of fermion fields and their equations of motion from a typical textbook on quantum field theory leads to some confusing or even wrong statements which we clarify here. In particular, we illustrate clearly that a Dirac fermion mass eigenstate is mathematically equivalent to two degenerated Majorana fermion mass eigenstates at least as long as the mass terms are concerned. There are further ambiguities and subtleties in the exact description of the eigenstate(s). Especially, for the case of neutrinos, the use of the Dirac or Majorana terminology may be mostly a matter of choice. The common usage of such terminology is rather based on the broken SU(2) charges of the related Weyl spinors hence conventional and may not be unambiguously extended to cover more complicate models. - Highlights: • Structure of fermion mass terms in practical quantum field theory is reviewed. • Important subtleties and ambiguities on the subject are clarified. • A mass eigenstate Dirac fermion and two degenerated Majorana ones are equivalent. • The conventional meaning of such terminology for neutrinos is critically discussed.

  20. Application of quantitative NMR for purity determination of standard ACE inhibitors.

    PubMed

    Shen, Shi; Yang, Xing; Shi, Yaqin

    2015-10-10

    This study investigated the accuracy of the quantitative NMR method for purity determination of ACE inhibitors reference standards and the discovery of two pairs of new diastereoisomers. Six types of ACE inhibitors, imidapril hydrochloride, benazepril hydrochloride, lisinopril, enalapril maleate, quinapril hydrochloride, and captopril were quantificated and validated for the qNMR method by discussing factors that affect parameters of the qNMR experiment, internal standards, integration, pH-effect, and uncertainty. The results were compared with data obtained by the mass balance method. The study found that maleic acid influenced the quantification of captopril in deuteroxide because of a chemical reaction. The mixtures of the reaction products were isolated by HPLC and structurally elucidated by NMR as two pairs of new diastereoisomers, 1-[(2S,4R)-thio-2-methylpropionyl-5-d-ethanedicarboxylicacid]-L-proline and 1-[(2S,4S)-thio-2-methylpropionyl-5-d-ethanedicarboxylicacid]-L-proline. The results showed that the accuracy and precision of quantitative (1)H NMR spectroscopy satisfied the requirements for quantitative analysis of chemical reference standards and provided a simple, rapid, and reliable method for purity determination of ACE inhibitors systematically. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Recyclable Strategy for the Production of High-Purity Galacto-oligosaccharides by Kluyveromyces lactis.

    PubMed

    Sun, Huaisheng; You, Shengping; Wang, Mengfan; Qi, Wei; Su, Rongxin; He, Zhimin

    2016-07-20

    A recyclable strategy for the production of high-purity (>95%) galacto-oligosaccharides (GOS) was developed using Kluyveromyces lactis in both the synthesis and purification steps. For the synthesis of GOS, ethanol-permeabilized cells (p-cells) of K. lactis were used because the enhanced permeability facilitated the mass transfer of the substrate and the release of oligosaccharide products. For the purification of GOS, non-permeabilized K. lactis cells (np-cells) were preferred as a result of their intrinsic cell membrane barrier toward GOS, which led to the selective consumption of carbohydrate. In this way, undesired glucose, galactose, and lactose in the raw GOS solution can be completely removed. This strategy is recyclable not only because of the high stability and reusability of p-cells and np-cells but also because the ethanol, which is simultaneously generated during the purification, can be reused for the preparation of p-cells. The strategy proposed in this study is a promising candidate for the efficient production of high-purity GOS.

  2. Novel Molten Oxide Membrane for Ultrahigh Purity Oxygen Separation from Air.

    PubMed

    Belousov, Valery V; Kulbakin, Igor V; Fedorov, Sergey V; Klimashin, Anton A

    2016-08-31

    We present a novel solid/liquid Co3O4-36 wt % Bi2O3 composite that can be used as molten oxide membrane, MOM ( Belousov, V. V. Electrical and Mass Transport Processes in Molten Oxide Membranes. Ionics 22 , 2016 , 451 - 469 ), for ultrahigh purity oxygen separation from air. This membrane material consists of Co3O4 solid grains and intergranular liquid channels (mainly molten Bi2O3). The solid grains conduct electrons, and the intergranular liquid channels predominantly conduct oxygen ions. The liquid channels also provide the membrane material gas tightness and ductility. This last property allows us to deal successfully with the problem of thermal incompatibility. Oxygen and nitrogen permeation fluxes, oxygen ion transport number, and conductivity of the composite were measured by the gas flow, volumetric measurements of the faradaic efficiency, and four-probe dc techniques, accordingly. The membrane material showed the highest oxygen selectivity jO2/jN2 > 10(5) and sufficient oxygen permeability 2.5 × 10(-8) mol cm(-1) s(-1) at 850 °C. In the range of membrane thicknesses 1.5-3.3 mm, the oxygen permeation rate was controlled by chemical diffusion. The ease of the MOM fabrication, combined with superior oxygen selectivity and competitive oxygen permeability, shows the promise of the membrane material for ultrahigh purity oxygen separation from air.

  3. Characterization of high purity lycopene from tomato wastes using a new pressurized extraction approach.

    PubMed

    Naviglio, Daniele; Caruso, Tonino; Iannece, Patrizia; Aragòn, Alejandro; Santini, Antonello

    2008-08-13

    In this paper, a method for the extraction of high purity lycopene from tomato wastes is presented. The method is based on a pressurized extraction that uses the Extractor Naviglio, and it is performed in the 0.7-0.9 MPa range. Tomato skin, the byproduct deriving from manufacturing of tomato, in a water dispersion, are used as starting material. Lycopene is transferred, for the effect of the high pressure used, in the form of molecular aggregates into the water as a dispersion, while apolar compounds remain in the matrix. The aggregates are easily purified in a single subsequent step by using methanol, thus, obtaining lycopene at 98% chromatographic purity or higher. A new stationary phase, phenyl-hexyl silicone, and a simple water/acetonitrile gradient were used for HPLC analysis of lycopene. The extract was characterized by UV-Vis spectrophotometry, (1)H NMR, (13)C NMR, and electrospray ionization mass spectrometry. An average recovery of 2.8 mg lycopene/kg tomato waste can be obtained after 4 hours of extraction and using tap water as the extracting liquid. The recovery percentage was of about 10%. The exhausted tomato byproduct can be easily dried and used in agriculture or as feeding for animals.

  4. Final report of the key comparison CCQM-K72: Purity of zinc with respect to six defined metallic analytes

    NASA Astrophysics Data System (ADS)

    Vogl, Jochen; Kipphardt, Heinrich; del Rocío Arvizu Torres, María; Manzano, Judith Velina Lara; Marques Rodrigues, Janaína; Caciano de Sena, Rodrigo; Yim, Yong-Hyeon; Heo, Sung Woo; Zhou, Tao; Turk, Gregory C.; Winchester, Michael; Yu, Lee L.; Miura, Tsutomu; Methven, B.; Sturgeon, Ralph; Jährling, Reinhard; Rienitz, Olaf; Tunç, Murat; Zühtü Can, Süleyman

    2014-01-01

    High purity elements can serve as a realization of the SI unit amount of substance for the specific element. Solutions prepared from high purity metals by applying gravimetric preparation and the concept of molar mass are used as 'calibration' solutions in many fields of analytical chemistry and provide the metrological basis in elemental analysis. Since ideal purity does not exist for real materials, the actual purity of the high purity material must be known with a specified uncertainty. As required uncertainties around 10-4 relative on the purity statement are not accessible in almost all cases by a direct measurement of the element in itself, the indirect approach is followed, where all elements excepting the matrix element itself are measured and their sum is subtracted from the value for ideal purity, which is 1 kg/kg. It was the aim of this comparison to demonstrate the capability of national metrology institutes and designated institutes to determine the purity of pure elements. In order to limit the effort within this comparison, only six metallic impurities (Ag, Al, Cd, Cr, Ni, Tl) in the low mg/kg range are considered in a zinc matrix. It has to be underlined here that the task was to measure the purity of zinc based on the determination of six analytes. The task is not trace analysis of specific analytes in zinc. This subtle distinction defines different measurands. The sample, pure Zn, was cut in pieces of cubic geometry for wet chemical analysis or of pin geometry for GDMS analysis and was sent to the participants. The comparison was run under the auspices of the Inorganic analysis Working Group (IAWG) of the CCQM and was piloted by the BAM Federal Institute for Materials Research and Testing, Berlin, Germany. The majority of the participants applied ICP-MS techniques and only two participants used additionally atomic absorption spectrometry. GDMS was used only by one participant. The observed spreads for the measurement results reported by the

  5. Molecular eigenstate spectroscopy: Application to the intramolecular dynamics of some polyatomic molecules in the 3000 to 7000 cm{sup {minus}1} region

    SciTech Connect

    Perry, D.S.

    1993-12-01

    Intramolecular vibrational redistribution (IVR) appears to be a universal property of polyatomic molecules in energy regions where the vibrational density of states is greater than about 5 to 30 states per cm{sup {minus}1}. Interest in IVR stems from its central importance to the spectroscopy, photochemistry, and reaction kinetics of these molecules. A bright state, {var_phi}{sub s}, which may be a C-H stretching vibration, carries the oscillator strength from the ground state. This bright state may mix with bath rotational-vibrational levels to form a clump of molecular eigenstates, each of which carries a portion of the oscillator strength from the ground state. In this work the authors explicitly resolve transitions to each of these molecular eigenstates. Detailed information about the nature of IVR is contained in the frequencies and intensities of the observed discrete transitions. The primary goal of this research is to probe the coupling mechanisms by which IVR takes place. The most fundamental distinction to be made is between anharmonic coupling which is independent of molecular rotation and rotationally-mediated coupling. The authors are also interested in the rate at which IVR takes place. Measurements are strictly in the frequency domain but information is obtained about the decay of the zero order state, {var_phi}{sub s}, which could be prepared in a hypothetical experiment as a coherent excitation of the clump of molecular eigenstates. As the coherent superposition dephases, the energy would flow from the initially prepared mode into nearby overtones and combinations of lower frequency vibrational modes. The decay of the initially prepared mode is related to a pure sequence infrared absorption spectrum by a Fourier transform.

  6. Background Knowledge Integration in Clustering Using Purity Indexes

    NASA Astrophysics Data System (ADS)

    Forestier, Germain; Wemmert, Cédric; Gançarski, Pierre

    In recent years, the use of background knowledge to improve the data mining process has been intensively studied. Indeed, background knowledge along with knowledge directly or indirectly provided by the user are often available. However, it is often difficult to formalize this kind of knowledge, as it is often dependent of the domain. In this article, we studied the integration of knowledge as labeled objects in clustering algorithms. Several criteria allowing the evaluation of the purity of a clustering are presented and their behaviours are compared using artificial datasets. Advantages and drawbacks of each criterion are analyzed in order to help the user to make a choice among them.

  7. Neutron energy determination with a high-purity germanium detector

    NASA Technical Reports Server (NTRS)

    Beck, Gene A.

    1992-01-01

    Two areas that are related to planetary gamma-ray spectrometry are investigated. The first task was the investigation of gamma rays produced by high-energy charged particles and their secondaries in planetary surfaces by means of thick target bombardments. The second task was the investigation of the effects of high-energy neutrons on gamma-ray spectral features obtained with high-purity Ge-detectors. For both tasks, as a function of the funding level, the experimental work was predominantly tied to that of other researchers, whenever there was an opportunity to participate in bombardment experiments at large or small accelerators for charged particles.

  8. Method and apparatus for producing high purity silicon

    DOEpatents

    Olson, Jerry M.

    1984-01-01

    A method for producing high purity silicon includes forming a copper silie alloy and positioning the alloy within an enclosure. A filament member is also placed within the enclosure opposite the alloy. The enclosure is then filled with a chemical vapor transport gas adapted for transporting silicon. Finally, both the filament member and the alloy are heated to temperatures sufficient to cause the gas to react with silicon at the alloy surface and deposit the reacted silicon on the filament member. In addition, an apparatus for carrying out this method is also disclosed.

  9. A novel method to synthesize high purity, nanostructured copper

    SciTech Connect

    Hodge, A M; Wang, Y M; Barbee, T W

    2005-08-30

    Nanostructured high purity (99.999%) copper foils, 10 cm in diameter and 22-25 microns thick were produced using nanoscale multilayer technology. The foils were produced using five different layer thicknesses ranging from 1.25 to 43.6 nm (18,000 to 520 layers). This process delivers the ability to produce multiple large-scale samples during a single deposition run with very small residual stresses. Tensile and indentation tests demonstrate that the material produced is a high strength copper ({sigma}{sub y} {approx} 540-690 MPa).

  10. A purity monitor for the KEDR liquid krypton calorimeter

    SciTech Connect

    Evtushenko, P. N.; Kotov, K. Yu.; Maslennikov, A. L.; Peleganchuk, S. V.; Snopkov, R. G.; Rogozin, A. I.; Tikhonov, Yu. A.

    2016-06-01

    We present a purity monitor for the KEDR liquid krypton calorimeter. A new method is suggested based on the usage of a short pulse of a gas discharge as a source of ultraviolet radiation for the photoproduction of electrons in a drift cell of the monitor. This paper describes the design of the monitor, the results of experiments with gaseous and liquid krypton, as well as the experience of using the developed device in the process of krypton purification for the KEDR liquid krypton calorimeter.

  11. The GALATEA test-facility for high purity germanium detectors

    NASA Astrophysics Data System (ADS)

    Abt, I.; Caldwell, A.; Dönmez, B.; Garbini, L.; Irlbeck, S.; Majorovits, B.; Palermo, M.; Schulz, O.; Seitz, H.; Stelzer, F.

    2015-05-01

    GALATEA is a test facility designed to investigate bulk and surface effects in high purity germanium detectors. A vacuum tank houses a cold volume with the detector inside. A system of three precision motorized stages allows an almost complete scan of the detector. The main feature of GALATEA is that there is no material between source and detector. This allows the usage of alpha and beta sources to study surface effects. A 19-fold segmented true-coaxial germanium detector was used for commissioning. A first analysis of data obtained with an alpha source is presented here.

  12. Bulk and surface effects in segmented high purity germanium detectors

    NASA Astrophysics Data System (ADS)

    Abt, I.; Caldwell, A.; Dönmez, B.; Irlbeck, S.; Majorovits, B.; Volynets, O.

    2013-08-01

    Segmented high-purity germanium detectors have been developed for a variety of experiments. The segmentation is used to augment the excellent energy resolution of such a device with spatial information to disentangle event topologies. Several performance aspects of true-coaxial segmented detectors are presented, especially the effects due to the crystallographic axes and the problem of events close to the surfaces of the detector. A test stand and Monte Carlo tools developed to study such effects are introduced. The simulation tools can also be used to design novel detectors, such as segmented point-contact detectors. A particular design is presented and discussed.

  13. The importance of Soret transport in the production of high purity silicon for solar cells

    NASA Technical Reports Server (NTRS)

    Srivastava, R.

    1985-01-01

    Temperature-gradient-driven diffusion, or Soret transport, of silicon vapor and liquid droplets is analyzed under conditions typical of current production reactors for obtaining high purity silicon for solar cells. Contrary to the common belief that Soret transport is negligible, it is concluded that some 15-20 percent of the silicon vapor mass flux to the reactor walls is caused by the high temperature gradients that prevail inside such reactors. Moreover, since collection of silicon is also achieved via deposition of silicon droplets onto the walls, the Soret transport mechanism becomes even more crucial due to size differences between diffusing species. It is shown that for droplets in the 0.01 to 1 micron diameter range, collection by Soret transport dominates both Brownian and turbulent mechanisms.

  14. The importance of Soret transport in the production of high purity silicon for solar cells

    NASA Technical Reports Server (NTRS)

    Srivastava, R.

    1985-01-01

    Temperature-gradient-driven diffusion, or Soret transport, of silicon vapor and liquid droplets is analyzed under conditions typical of current production reactors for obtaining high purity silicon for solar cells. Contrary to the common belief that Soret transport is negligible, it is concluded that some 15-20 percent of the silicon vapor mass flux to the reactor walls is caused by the high temperature gradients that prevail inside such reactors. Moreover, since collection of silicon is also achieved via deposition of silicon droplets onto the walls, the Soret transport mechanism becomes even more crucial due to size differences between diffusing species. It is shown that for droplets in the 0.01 to 1 micron diameter range, collection by Soret transport dominates both Brownian and turbulent mechanisms.

  15. Vibrational dynamics of the bifluoride ion. III. F-F (ν1) eigenstates and vibrational intensity calculations

    NASA Astrophysics Data System (ADS)

    Epa, V. C.; Thorson, W. R.

    1990-09-01

    This paper concludes a theoretical study of vibrational dynamics in the bifluoride ion FHF-, which exhibits strongly anharmonic and coupled motions. Two previous papers have described an extended model potential surface for the system, developed a scheme for analysis based on a zero-order adiabatic separation of the proton bending and stretching motions (ν2,ν3) from the slower F-F symmetric-stretch motion (ν1), and presented results of accurate calculations of the adiabatic protonic eigenstates. Here the ν1 motion has been treated, in adiabatic approximation and also including nonadiabatic couplings in close-coupled calculations with up to three protonic states (channels). States of the system involving more than one quantum of protonic excitation (e.g., 2ν2, 2ν3 σg states; 3ν2, ν2+2ν3 πu states; ν3+2ν2, 3ν3 σu states) exhibit strong mixing at avoided crossings of protonic levels, and these effects are discussed in detail. Dipole matrix elements and relative intensities for vibrational transitions have been computed with an electronic dipole moment function based on ab initio calculations for an extended range of geometries. Frequencies, relative IR intensities and other properties of interest are compared with high resolution spectroscopic data for the gas-phase free ion and with the IR absorption spectra of KHF2(s) and NaHF2(s). Errors in the ab initio potential surface yield fundamental frequencies ν2 and ν3 100-250 cm-1 higher than those observed in either the free ion or the crystalline solids, but these differences are consistent and an unambiguous assignment of essentially all transitions in the IR spectrum of KHF2 is made. Calculated relative intensities for stretching mode (ν3, σu symmetry) transitions agree well with those observed in both KHF2 [e.g., bands (ν3+nν1), (ν3+2ν2), (3ν3), etc.] and the free ion (ν3,ν3+ν1). Calculated intensities for bending mode (ν2, πu symmetry) transitions agree well with experiment for the ν2

  16. High purity polyimide analysis by solid sampling graphite furnace atomic absorption spectrometry

    NASA Astrophysics Data System (ADS)

    Santos, Rafael F.; Carvalho, Gabriel S.; Duarte, Fabio A.; Bolzan, Rodrigo C.; Flores, Erico M. M.

    2017-03-01

    In this work, Cr, Cu, Mn, Na and Ni were determined in high purity polyimides (99.5%) by solid sampling graphite furnace atomic absorption spectrometry (SS-GFAAS) using Zeeman effect background correction system with variable magnetic field, making possible the simultaneous measurement at high or low sensitivity. The following analytical parameters were evaluated: pyrolysis and atomization temperatures, feasibility of calibration with aqueous solution, linear calibration range, sample mass range and the use of chemical modifier. Calibration with aqueous standard solutions was feasible for all analytes. No under or overestimated results were observed and up to 10 mg sample could be introduced on the platform for the determination of Cr, Cu, Mn, Na and Ni. The relative standard deviation ranged from 3 to 20%. The limits of detection (LODs) achieved using the high sensitivity mode were as low as 7.0, 2.5, 1.7, 17 and 0.12 ng g- 1 for Cr, Cu, Mn, Na and Ni, respectively. No addition of chemical modifier was necessary, except for Mn determination where Pd was required. The accuracy was evaluated by analyte spike and by comparison of the results with those obtained by inductively coupled plasma optical emission spectrometry and inductively coupled plasma mass spectrometry after microwave-assisted digestion in a single reaction chamber system and also by neutron activation analysis. No difference among the results obtained by SS-GFAAS and those obtained by alternative analytical methods using independent techniques. SS-GFAAS method showed some advantages, such as the determination of metallic contaminants in high purity polyimides with practically no sample preparation, very low LODs, calibration with aqueous standards and determination in a wide range of concentration.

  17. Influence of salt purity on Na+ and palmitic acid interactions.

    PubMed

    Huang, Zishuai; Hua, Wei; Verreault, Dominique; Allen, Heather C

    2013-12-19

    The influence of salt purity on the interactions between Na(+) ions and the carboxylate (COO(-)) head group of palmitic acid (PA) monolayers is studied in the COO(-) and OH stretching regions using broad-band vibrational sum frequency generation (VSFG) spectroscopy. Ultrapure (UP) and ACS grade NaCl salts are used for aqueous solution preparation after proper pretreatment. The time evolution of VSFG spectra of PA monolayers on solutions made from these two grades of salts is different, which reveals that the salt purity has a significant impact on the interactions between Na(+) ions and the COO(-) group of PA. The trace metal impurities in ACS grade salt, which are more abundant than those in UP grade salt, are responsible for this difference due to their stronger affinity for the carboxylate group relative to Na(+) and further affects the interfacial water structure. These results suggest that the alkali salt grade even after pretreatment is critical in the studies of alkali cation-carboxylate interactions and comparison of relative binding affinities of different cations.

  18. Dialysis water and fluid purity: more than endotoxin.

    PubMed

    Glorieux, Griet; Neirynck, Nathalie; Veys, Nic; Vanholder, Raymond

    2012-11-01

    The evolution of extracorporeal treatment of end-stage renal failure has enforced focus on the purity of dialysis fluid. A major challenge of high-flux haemodialysis (HD) and haemodiafiltration relates to the necessity for ultrapure dialysis fluid and for sterile non-pyrogenic substitution fluid. The present review focuses especially on the possible microbial contamination including, next to intact micro-organisms, a variety of microbial derivatives. It is pointed out that there are conditions (e.g. contamination by non-culturable micro-organisms or bacterial derivatives other than lipopolysaccharides) where the detection of biologically relevant contaminants can be missed when applying the recommended standard detection methods such as bacterial culture and limulus amoebocyte lysate test. Possible approaches for action upon positive sampling results, exceeding the levels recommended in the latest ISO 11663:2009, are described in detail and illustrated with flow charts. The issue of purity of dialysis fluids is highly relevant, since the chronic exposure of HD patients to low levels of cytokine-inducing microbial components can significantly contribute to the micro-inflammatory status of these patients.

  19. Laser heating method for estimation of carbon nanotube purity

    NASA Astrophysics Data System (ADS)

    Terekhov, S. V.; Obraztsova, E. D.; Lobach, A. S.; Konov, V. I.

    A new method of a carbon nanotube purity estimation has been developed on the basis of Raman spectroscopy. The spectra of carbon soot containing different amounts of nanotubes were registered under heating from a probing laser beam with a step-by-step increased power density. The material temperature in the laser spot was estimated from a position of the tangential Raman mode demonstrating a linear thermal shift (-0.012 cm-1/K) from the position 1592 cm-1 (at room temperature). The rate of the material temperature rise versus the laser power density (determining the slope of a corresponding graph) appeared to correlate strongly with the nanotube content in the soot. The influence of the experimental conditions on the slope value has been excluded via a simultaneous measurement of a reference sample with a high nanotube content (95 vol.%). After the calibration (done by a comparison of the Raman and the transmission electron microscopy data for the nanotube percentage in the same samples) the Raman-based method is able to provide a quantitative purity estimation for any nanotube-containing material.

  20. A 99 percent purity molecular sieve oxygen generator

    NASA Technical Reports Server (NTRS)

    Miller, G. W.

    1991-01-01

    Molecular sieve oxygen generating systems (MSOGS) have become the accepted method for the production of breathable oxygen on military aircraft. These systems separate oxygen for aircraft engine bleed air by application of pressure swing adsorption (PSA) technology. Oxygen is concentrated by preferential adsorption in nitrogen in a zeolite molecular sieve. However, the inability of current zeolite molecular sieves to discriminate between oxygen and argon results in an oxygen purity limitations of 93-95 percent (both oxygen and argon concentrate). The goal was to develop a new PSA process capable of exceeding the present oxygen purity limitations. A novel molecular sieve oxygen concentrator was developed which is capable of generating oxygen concentrations of up to 99.7 percent directly from air. The process is comprised of four absorbent beds, two containing a zeolite molecular sieve and two containing a carbon molecular sieve. This new process may find use in aircraft and medical breathing systems, and industrial air separation systems. The commercial potential of the process is currently being evaluated.

  1. High-purity silica reflecting heat shield development

    NASA Technical Reports Server (NTRS)

    Congdon, W. M.

    1974-01-01

    A high-purity, fused-silica reflecting heat shield for the thermal protection of outer-planet probes was developed. Factors that strongly influence the performance of a silica heat shield were studied. Silica-bonded silica configurations, each prepared by a different technique, were investigated and rated according to its relative merits. Slip-casting was selected as the preferred fabrication method because it produced good reflectivity and good strength, and is relatively easy to scale up for a full-size outer-planet probe. The slips were cast using a variety of different particle sizes: continuous particle-size slips; monodisperse particle-size slips; and blends of monodisperse particle-size slips were studied. In general, smaller particles gave the highest reflectance. The monodisperse slips as well as the blend slips gave a higher reflectance than the continuous particle-size slips. An upgraded and fused natural quartz was used to study the effects of microstructure on reflectance and as the baseline to ascertain the increase in reflectance obtained from using a higher-purity synthetic material.

  2. Preparation of high purity egg phosvitin using anion exchange chromatography.

    PubMed

    Ren, Jiandong; Wu, Jianping

    2014-09-01

    Egg yolk phosvitin serves as a warehouse to provide metal ions for embryo development. It is significant for mineral metabolism study and also of great potential to be developed into functional foods with mineral absorption promoting ability. In this study, phosvitin was first extracted from yolk granules using 10% NaCl, dialysed and then adjusted to various pHs to remove impurities. The purity of phosvitin extracts was increased from 54.5% to 63.7% at decreasing pH from 8.0 to 5.5, and started to decrease afterwards. Both the yield and recovery were significantly decreased at decreasing pHs, especially at pHs close to its pI (pH 4.0), indicating the occurrence of co-precipitation of phosvitin with HDL. The extract prepared at pH 8.0 showed the highest recovery of 82.7%; its purity was increased from 54.5% to 97.1% by anion exchange chromatography, with a recovery of 42.0%. This simple method could be scaled up for industrial production.

  3. The compressibility of high purity YbB2.

    PubMed

    Kalkan, B; Suzer, S; Ozdas, E

    2012-08-29

    The compressibility and phase stability of Y bB(2) are investigated under high pressure using high-resolution synchrotron x-ray diffraction in a diamond anvil cell. The bulk modules of high purity Y bB(2) is obtained as ∼182 GPa using the Birch-Murnaghan equation of state. The patterns measured up to 20 GPa and the pressure dependence of normalized lattice parameters, a/a(0) and c/c(0), reveal that the compressibility of Y bB(2) is low and fairly isotropic, and this material can be classified as a hard material. X-ray photoemission studies demonstrate that Yb in Y bB(2) has a mostly trivalent valence state at room temperature. Moreover, sample preparation details provide a new insight into the high purity synthesis of Y bB(2) at ambient pressure and moderate temperatures. The presented structural and compressibility results are in agreement with the available theoretical and experimental data on binary rare-earth borides and can serve as a reliable reference for future studies.

  4. Recent developments in high purity niobium metal production at CBMM

    SciTech Connect

    Abdo, Gustavo Giovanni Ribeiro Sousa, Clovis Antonio de Faria Guimarães, Rogério Contato Ribas, Rogério Marques Vieira, Alaércio Salvador Martins Menezes, Andréia Duarte Fridman, Daniel Pallos Cruz, Edmundo Burgos

    2015-12-04

    CBMM is a global supplier of high quality niobium products including pure niobium, the focus of this paper. CBMM’s position has been consolidated over three decades of producing high purity niobium metal ingots. The company supplies, among other products, commercial and reactor grade niobium ingots. One of the main uses of CBMM’s ingots is for the manufacture of particle accelerators (superconducting radio frequency – SRF – cavities), where the purity and homogeneity of niobium metal is essentially important for good performance. CBMM constantly strives to improve process controls and product quality, and is currently implementing innovations in production, research and development to further improve ingot quality. The main aim is to reduce the content of interstitial elements, such as nitrogen (N), oxygen (O), carbon (C), and hydrogen (H), starting with the raw materials through the final step of ingot production. CBMM held the first trial to produce the world’s largest-diameter niobium ingot (as cast 535 mm). The results of this initial trial presented very low levels of interstitial impurities (N, O, C, H), allowing the achievement of residual resistivity ratio (RRR) values very close to 300 in a six-melt process in an electron beam furnace. These values were reached with 850 ppm of tantalum. SRF cavities will be produced with this material in order to study the effect of low impurities and high RRR on the Q factor and accelerating gradient.

  5. Recent developments in high purity niobium metal production at CBMM

    NASA Astrophysics Data System (ADS)

    Abdo, Gustavo Giovanni Ribeiro; Sousa, Clovis Antonio de Faria; Guimarães, Rogério Contato; Ribas, Rogério Marques; Vieira, Alaércio Salvador Martins; Menezes, Andréia Duarte; Fridman, Daniel Pallos; Cruz, Edmundo Burgos

    2015-12-01

    CBMM is a global supplier of high quality niobium products including pure niobium, the focus of this paper. CBMM's position has been consolidated over three decades of producing high purity niobium metal ingots. The company supplies, among other products, commercial and reactor grade niobium ingots. One of the main uses of CBMM's ingots is for the manufacture of particle accelerators (superconducting radio frequency - SRF - cavities), where the purity and homogeneity of niobium metal is essentially important for good performance. CBMM constantly strives to improve process controls and product quality, and is currently implementing innovations in production, research and development to further improve ingot quality. The main aim is to reduce the content of interstitial elements, such as nitrogen (N), oxygen (O), carbon (C), and hydrogen (H), starting with the raw materials through the final step of ingot production. CBMM held the first trial to produce the world's largest-diameter niobium ingot (as cast 535 mm). The results of this initial trial presented very low levels of interstitial impurities (N, O, C, H), allowing the achievement of residual resistivity ratio (RRR) values very close to 300 in a six-melt process in an electron beam furnace. These values were reached with 850 ppm of tantalum. SRF cavities will be produced with this material in order to study the effect of low impurities and high RRR on the Q factor and accelerating gradient.

  6. Discussion on the purity and the crystallization of CZTS compound

    NASA Astrophysics Data System (ADS)

    Tablaoui, M.; Derbal, M.; Lebbou, K.

    2016-10-01

    Cu2ZnSnS4 is a new material with low extraction cost. It belongs to Cu-Zn-Sn-S quaternary system and has recently attracted great attention as promising photovoltaic material. Due to its interesting properties such as a band-gap around 1.5 eV and a large absorption coefficient in the order of 104 cm-1. This compound is considered as ideal for effective phonon absorption and photo-generation. Since the sulfur is an important element in the stoichiometric composition, the effect of its content on the purity, the stability and the crystallization of this material has been taken in account. High purity Cu2ZnSnS4 single phase compound, with an excess sulfur starting concentration lying in the range 3-20 wt%, could be obtained. In these conditions, Cu2ZnSnS4 alloy has been synthesized and vertically well textured along the melt flow. Depending on the additional sulfur amount at the starting charge, it was possible to control both the solidification conditions and the morphology of Cu2ZnSnS4 phase. As a result, the solidification process allowed us to control the as grown crystal under stationary stable regime.

  7. A cultural look at moral purity: wiping the face clean

    PubMed Central

    Lee, Spike W. S.; Tang, Honghong; Wan, Jing; Mai, Xiaoqin; Liu, Chao

    2015-01-01

    Morality is associated with bodily purity in the custom of many societies. Does that imply moral purity is a universal psychological phenomenon? Empirically, it has never been examined, as all prior experimental data came from Western samples. Theoretically, we suggest the answer is not so straightforward—it depends on the kind of universality under consideration. Combining perspectives from cultural psychology and embodiment, we predict a culture-specific form of moral purification. Specifically, given East Asians' emphasis on the face as a representation of public self-image, we hypothesize that facial purification should have particularly potent moral effects in a face culture. Data show that face-cleaning (but not hands-cleaning) reduces guilt and regret most effectively against a salient East Asian cultural background. It frees East Asians from guilt-driven prosocial behavior. In the wake of their immorality, they find a face-cleaning product especially appealing and spontaneously choose to wipe their face clean. These patterns highlight both culturally variable and universal aspects of moral purification. They further suggest an organizing principle that informs the vigorous debate between embodied and amodal perspectives. PMID:26029134

  8. Development of high purity large forgings for nuclear power plants

    NASA Astrophysics Data System (ADS)

    Tanaka, Yasuhiko; Sato, Ikuo

    2011-10-01

    The recent increase in the size of energy plants has been supported by the development of manufacturing technology for high purity large forgings for the key components of the plant. To assure the reliability and performance of the large forgings, refining technology to make high purity steels, casting technology for gigantic ingots, forging technology to homogenize the material and consolidate porosity are essential, together with the required heat treatment and machining technologies. To meet these needs, the double degassing method to reduce impurities, multi-pouring methods to cast the gigantic ingots, vacuum carbon deoxidization, the warm forging process and related technologies have been developed and further improved. Furthermore, melting facilities including vacuum induction melting and electro slag re-melting furnaces have been installed. By using these technologies and equipment, large forgings have been manufactured and shipped to customers. These technologies have also been applied to the manufacture of austenitic steel vessel components of the fast breeder reactors and components for fusion experiments.

  9. Explaining solar neutrinos with heavy Higgs masses in partial split supersymmetry

    SciTech Connect

    Diaz, Marco Aurelio; Garay, Francisca; Koch, Benjamin

    2009-12-01

    Partial Split Supersymmetry with violation of R-parity as a model for neutrino masses is explored. It is shown that at the one-loop level the model can give predictions that are in agreement with all present experimental values for the neutrino sector. An analytical result is that the small solar neutrino mass difference can be naturally explained in the decoupling limit for the heavy Higgs mass eigenstates.

  10. Direct neutrino mass measurements

    NASA Astrophysics Data System (ADS)

    Thümmler, T.

    2011-07-01

    The determination of the neutrino rest mass plays an important role at the intersections of cosmology, particle physics and astroparticle physics. This topic is currently being addressed by two complementary approaches in laboratory experiments. Neutrinoless double beta decay experiments probe whether neutrinos are Majorana particles and determine an effective neutrino mass value. Single beta decay experiments such as KATRIN and MARE investigate the spectral shape of β-decay electrons close to their kinematic endpoint in order to determine the neutrino rest mass with a model-independent method. Owing to neutrino flavour mixing, the neutrino mass parameter appears as an average of all neutrino mass eigenstates contributing to the electron neutrino. The KArlsruhe TRItium Neutrino experiment (KATRIN) is currently the experiment in the most advanced status of commissioning. Applying an ultra-luminous molecular windowless gaseous tritium source and an integrating high-resolution spectrometer of MAC-E filter type, it allows β-spectroscopy close to the T 2 end-point with unprecedented precision and will reach a sensitivity of 200 meV/ c 2 (90% C.L.) on the neutrino rest mass.

  11. Analysis of dye degradation products and assessment of the dye purity in dye-sensitized solar cells.

    PubMed

    Rendon, Sabine M K; Mavrynsky, Denys; Meierjohann, Axel; Tiihonen, Armi; Miettunen, Kati; Asghar, Imran; Halme, Janne; Kronberg, Leif; Leino, Reko

    2015-12-15

    For commercialization of dye-sensitized solar cells (DSSCs), improvement of their long-term stability and efficiency is important. A key component in solar cells is the dye, its high purity and high stability. Here, methods for dye extraction and purification, and for determination of dye purity and dye degradation in DSSCs, were developed. A method was developed for extraction of the dye Z907 from intact solar cells using a water/ethanol mixture containing tetrabutylammonium hydroxide. The N719 dye synthesized in our laboratory was purified by gel filtration on Sephadex LH20. These dyes, along with the dyes N3 and RuL2 (NC)2, were analyzed using nuclear magnetic resonance (NMR) spectroscopy and liquid chromatography coupled to an electrospray ionization quadrupole-time-of-flight mass analyzer (LC/MS) operating in negative ionization mode. Purification of the synthesized N719 removed several impurities, including its undesired isomer with the thiocyanate ligand attached to ruthenium through sulfur instead of nitrogen. The dyes N719 and Z907 were successfully extracted from solar cells and together with N3 and RuL2 (NC)2 analyzed by LC/MS, although N719 isomerized almost immediately in basic aqueous solution. The [M-H](-1) ions were observed and the measured mass was within a ±6 ppm range from the exact mass. LC/MS in combination with NMR spectroscopy was shown to provide useful information on dye structure, purity, and on the efficiency of the purification methods. These methods allow for further studies of solar cell dyes, which may provide the detailed information needed for the improvement and eventual commercialization of the solar cell technology. Copyright © 2015 John Wiley & Sons, Ltd.

  12. Characteristics of GRIFFIN high-purity germanium clover detectors

    NASA Astrophysics Data System (ADS)

    Rizwan, U.; Garnsworthy, A. B.; Andreoiu, C.; Ball, G. C.; Chester, A.; Domingo, T.; Dunlop, R.; Hackman, G.; Rand, E. T.; Smith, J. K.; Starosta, K.; Svensson, C. E.; Voss, P.; Williams, J.

    2016-06-01

    The Gamma-Ray Infrastructure For Fundamental Investigations of Nuclei, GRIFFIN, is a new experimental facility for radioactive decay studies at the TRIUMF-ISAC laboratory. The performance of the 16 high-purity germanium (HPGe) clover detectors that will make up the GRIFFIN spectrometer is reported. The energy resolution, efficiency, timing resolution, crosstalk and preamplifier properties of each crystal were measured using a combination of analog and digital data acquisition techniques. The absolute efficiency and add-back factors are determined for the energy range of 80-3450 keV. The detectors show excellent performance with an average over all 64 crystals of a FWHM energy resolution of 1.89(6) keV and relative efficiency with respect to a 3 in . × 3 in . NaI detector of 41(1)% at 1.3 MeV.

  13. High spectral purity Kerr frequency comb radio frequency photonic oscillator

    PubMed Central

    Liang, W.; Eliyahu, D.; Ilchenko, V. S.; Savchenkov, A. A.; Matsko, A. B.; Seidel, D.; Maleki, L.

    2015-01-01

    Femtosecond laser-based generation of radio frequency signals has produced astonishing improvements in achievable spectral purity, one of the basic features characterizing the performance of an radio frequency oscillator. Kerr frequency combs hold promise for transforming these lab-scale oscillators to chip-scale level. In this work we demonstrate a miniature 10 GHz radio frequency photonic oscillator characterized with phase noise better than −60 dBc Hz−1 at 10 Hz, −90 dBc Hz−1 at 100 Hz and −170 dBc Hz−1 at 10 MHz. The frequency stability of this device, as represented by Allan deviation measurements, is at the level of 10−10 at 1–100 s integration time—orders of magnitude better than existing radio frequency photonic devices of similar size, weight and power consumption. PMID:26260955

  14. High-efficiency spectral purity filter for EUV lithography

    DOEpatents

    Chapman, Henry N.

    2006-05-23

    An asymmetric-cut multilayer diffracts EUV light. A multilayer cut at an angle has the same properties as a blazed grating, and has been demonstrated to have near-perfect performance. Instead of having to nano-fabricate a grating structure with imperfections no greater than several tens of nanometers, a thick multilayer is grown on a substrate and then cut at an inclined angle using coarse and inexpensive methods. Effective grating periods can be produced this way that are 10 to 100 times smaller than those produced today, and the diffraction efficiency of these asymmetric multilayers is higher than conventional gratings. Besides their ease of manufacture, the use of an asymmetric multilayer as a spectral purity filter does not require that the design of an EUV optical system be modified in any way, unlike the proposed use of blazed gratings for such systems.

  15. Precipitation of hydrides in high purity niobium after different treatments

    SciTech Connect

    Barkov, F.; Romanenko, A.; Trenikhina, Y.; Grassellino, A.

    2013-01-01

    Precipitation of lossy non-superconducting niobium hydrides represents a known problem for high purity niobium in superconducting applications. Using cryogenic optical and laser confocal scanning microscopy we have directly observed surface precipitation and evolution of niobium hydrides in samples after different treatments used for superconducting RF cavities for particle acceleration. Precipitation is shown to occur throughout the sample volume, and the growth of hydrides is well described by the fast diffusion-controlled process in which almost all hydrogen is precipitated at $T=140$~K within $\\sim30$~min. 120$^{\\circ}$C baking and mechanical deformation are found to affect hydride precipitation through their influence on the number of nucleation and trapping centers.

  16. Study on the Properties of High Purity Germanium Crystals

    NASA Astrophysics Data System (ADS)

    Yang, G.; Mei, H.; Guan, Y. T.; Wang, G. J.; Mei, D. M.; Irmscher, K.

    2015-05-01

    In the crystal growth lab of South Dakota University, we are growing high purity germanium (HPGe) crystals and using the grown crystals to make radiation detectors. As the detector grade HPGe crystals, they have to meet two critical requirements: an impurity level of ∼109 to 10 atoms /cm3 and a dislocation density in the range of ∼102 to 104 / cm3. In the present work, we have used the following four characterization techniques to investigate the properties of the grown crystals. First of all, an x-ray diffraction method was used to determine crystal orientation. Secondly, the van der Pauw Hall effect measurement was used to measure the electrical properties. Thirdly, a photo-thermal ionization spectroscopy (PTIS) was used to identify what the impurity atoms are in the crystal. Lastly, an optical microscope observation was used to measure dislocation density in the crystal. All of these characterization techniques have provided great helps to our crystal activities.

  17. Development of high purity niobium used in SRF accelerating cavity

    NASA Astrophysics Data System (ADS)

    Chen, Lin; Xie, Wei-Ping; Li, Ming-Yang; He, Ji-Lin; Fan, Hui-Ru; Zhang, Bao-Cheng; He, Fei-Si; Zhao, Kui; Chen, Jia-Er; Liu, Ke-Xin

    2008-12-01

    Niobium is widely used in SRF (Superconducting Radio Frequency) cavities due to its excellent superconductivity and workability. With the continuous development of technology, higher demands of material are raised. One of the key issues is that RRR (Residual Resistance Ratio) of the Nb material should be more than 300, which requires that the Nb ingot have even higher RRR. This article introduces the development and the experimental results of high purity niobium in OTIC in Ningxia (Ningxia Orient Tantalum Industry Co. Ltd.), and the test results of the single cell TESLA (Tera Electron volt energy Superconducting Linear Accelerator) shaped cavity manufactured by Peking University using Nb material from OTIC. Supported by National Basic Research Program of China (2002CB713600)

  18. Springback in Deep Drawn High Purity Niobium for Superconductor Cavities

    SciTech Connect

    Ganapati Rao Myneni; Peter Kneisel

    2005-09-01

    Superconducting radio frequency (SRF) cavities made from deep drawn high-purity niobium have become a popular approach for the design of particle accelerators. A number of current accelerators use this technology and it is a leading candidate for future designs. The development of this technology has required significant advances in many scientific fields including metallurgy, high vacuum physics, surface science, and forming. Recently proposed modifications to the current process for fabrication of these cavities has resulted in increased concern about the distribution of deformation, residual stress patterns, and springback. This presentation will report on the findings of a recently initiated program to study plastic flow and springback in the fabrication of these cavities and the influence of metallurgical variables including grain size and impurity content.

  19. A coulometric iodimetric procedure for measuring the purity of lewisite.

    SciTech Connect

    Sandi, G.; Brubaker, K. L.; Schneider, J. F.; O'Neill, H. J.

    2001-06-21

    A new analytical method for the determination of the purity of CASARM Lewisite samples (Chemical Agent Standard Analytical Reference Materials) has been developed and tested. The method essentially replaces the volumetric iodimetric procedures currently in use with the in-situ electrochemical generation of iodine. Tests on both arsenious acid and Lewisite/CVAA solutions show that the method is capable of achieving high accuracy and precision. Sample preparation and analysis times are considerably less than the current titrimetric method. The coulometric iodimetric method has been shown capable of determining not only total organic trivalent arsenic, but also total trivalent arsenic merely by adjusting the pH. Organic arsenic is determined at pH 4, and total trivalent arsenic at pH 8.

  20. Sugar Cube Purity: Capacitive Sensing and Image Processing Approach

    NASA Astrophysics Data System (ADS)

    Madhumitha, S.; Rajath, R.; Venkatanathan, N.; Raajan, N. R.; Sridharan, M.

    2016-12-01

    Several methods have been implemented to find out if impurity is present in sugar cubes or powders so far. Several high end imaging techniques with X-ray scanners have been used to check the quality of the sugar. In this present study, without disturbing the physical nature of sugar, we have simply used the dielectric property analysis to check the purity of the sugar. This method can detect even infinitesimal amounts of impurity present in sugar with good accuracy. The positional accuracy is derived using artificial neural networks, which is been trained with various capacitance values when the impurity is present and gives the details on the change in capacitance value as the impurity position changes.

  1. Structure of polarimetric purity of three-dimensional polarization states

    NASA Astrophysics Data System (ADS)

    Gil, José J.; Friberg, Ari T.; Setälä, Tero; San José, Ignacio

    2017-05-01

    It has recently been demonstrated that a general three-dimensional (3D) polarization state cannot be considered an incoherent superposition of (1) a pure state, (2) a two-dimensional unpolarized state, and (3) a 3D unpolarized state [J. J. Gil, Phys. Rev. A 90, 043858 (2014), 10.1103/PhysRevA.90.043858]. This fact is intimately linked to the existence of 3D polarization states with fluctuating directions of propagation, but whose associated polarization matrices R satisfy rank R =2 . In this work, such peculiar states are analyzed and characterized, leading to a meaningful general classification and interpretation of 3D polarization states. Within this theoretical framework, the interrelations among the more significant polarization descriptors presented in the literature, as well as their respective physical interpretations, are studied and illustrated with examples, providing a better understanding of the structure of polarimetric purity of any kind of polarization state.

  2. Different techniques for characterizing single-walled carbon nanotube purity

    NASA Astrophysics Data System (ADS)

    Yuca, Neslihan; Camtakan, Zeyneb; Karatepe, Nilgün

    2013-09-01

    Transition-metal catalysts, fullerenes, graphitic carbon, amorphous carbon, and graphite flakes are the main impurities in carbon nanotubes. In this study, we demonstrate an easy and optimum method of cleaning SWCNTs and evaluating their purity. The purification method, which employed oxidative heat treatment followed by 6M HNO3, H2SO4, HNO3:H2SO4 and HCl acid reflux for 6h at 120°C and microwave digestion with 1.5M HNO3 for 0.5h at 210°C which was straightforward, inexpensive, and fairly effective. The purified materials were characterized by thermogravimetric analysis and nuclear techniques such as INAA, XRF and XRD.

  3. Minkowski structure for purity and entanglement of Gaussian bipartite states

    NASA Astrophysics Data System (ADS)

    de Oliveira, Marcos C.; Nicacio, Fernando; Mizrahi, Salomon S.

    2013-11-01

    The relation between the symplectic and Lorentz groups is explored to investigate entanglement features in a two-mode bipartite Gaussian state. We verify that the correlation matrix of arbitrary Gaussian states can be associated with a hyperbolic space with a Minkowski metric, which is divided in two regions: separabilitylike and entanglementlike, in equivalence to timelike and spacelike in special relativity. This correspondence naturally allows the definition of two insightful invariant squared distance measures: one related to the purity and another related to amount of entanglement. The second distance allows us to define a measure for entanglement in terms of the invariant interval between the given state and its closest separable state, given in a natural manner without the requirement of a minimization procedure.

  4. High spectral purity Kerr frequency comb radio frequency photonic oscillator.

    PubMed

    Liang, W; Eliyahu, D; Ilchenko, V S; Savchenkov, A A; Matsko, A B; Seidel, D; Maleki, L

    2015-08-11

    Femtosecond laser-based generation of radio frequency signals has produced astonishing improvements in achievable spectral purity, one of the basic features characterizing the performance of an radio frequency oscillator. Kerr frequency combs hold promise for transforming these lab-scale oscillators to chip-scale level. In this work we demonstrate a miniature 10 GHz radio frequency photonic oscillator characterized with phase noise better than -60 dBc Hz(-1) at 10 Hz, -90 dBc Hz(-1) at 100 Hz and -170 dBc Hz(-1) at 10 MHz. The frequency stability of this device, as represented by Allan deviation measurements, is at the level of 10(-10) at 1-100 s integration time-orders of magnitude better than existing radio frequency photonic devices of similar size, weight and power consumption.

  5. Survey of the preparation, purity, and availability of silanes

    SciTech Connect

    Lorenz, J.H.

    1983-12-01

    Silane and disilane are currently available as prepared for the semiconductor market. Published or public information on preparative methods for monosilane and higher silanes are discussed. Purification techniques are reviewed. Data from current silane suppliers are tabulated. A short review of the silanes in Japan is given. Analytical procedures are not now perfected to determine group 3 or 5 elements in silane. All commercial silanes contain certain impurities. There is no simple one step purification technique for silane which a user could easily operate. Typical and actual analyses of commercial silane are given. Disilane is still in the development stage with only small quantities available at very high prices. The silane process developed in part under the DOE/JPL Flat Plate Solar Array project by Union Carbide is summarized. Higher purity silanes are now appearing on the market. These should be useful in the photovoltaic area.

  6. Secondary emission conductivity of high purity silica fabric

    NASA Technical Reports Server (NTRS)

    Belanger, V. J.; Eagles, A. E.

    1977-01-01

    High purity silica fabrics were proposed for use as a material to control the effects of electrostatic charging of satellites at synchronous altitudes. These materials exhibited very quiet behavior when placed in simulated charging environments as opposed to other dielectrics used for passive thermal control which exhibit varying degrees of electrical arcing. Secondary emission conductivity is proposed as a mechanism for this superior behavior. Design of experiments to measure this phenomena and data taken on silica fabrics are discussed as they relate to electrostatic discharge (ESD) control on geosynchronous orbit spacecraft. Studies include the apparent change in resistivity of the material as a function of the electron beam energy, flux intensity, and the effect of varying electric fields impressed across the material under test.

  7. Purity of Gaussian states: Measurement schemes and time evolution in noisy channels

    SciTech Connect

    Paris, Matteo G.A.; Illuminati, Fabrizio; Serafini, Alessio; De Siena, Silvio

    2003-07-01

    We present a systematic study of the purity for Gaussian states of single-mode continuous variable systems. We prove the connection of purity to observable quantities for these states, and show that the joint measurement of two conjugate quadratures is necessary and sufficient to determine the purity at any time. The statistical reliability and the range of applicability of the proposed measurement scheme are tested by means of Monte Carlo simulated experiments. We then consider the dynamics of purity in noisy channels. We derive an evolution equation for the purity of general Gaussian states both in thermal and in squeezed thermal baths. We show that purity is maximized at any given time for an initial coherent state evolving in a thermal bath, or for an initial squeezed state evolving in a squeezed thermal bath whose asymptotic squeezing is orthogonal to that of the input state.

  8. Impact of US and Canadian precursor regulation on methamphetamine purity in the United States.

    PubMed

    Cunningham, James K; Liu, Lon-Mu; Callaghan, Russell

    2009-03-01

    Reducing drug purity is a major, but largely unstudied, goal of drug suppression. This study examines whether US methamphetamine purity was impacted by the suppression policy of US and Canadian precursor chemical regulation. Autoregressive integrated moving average (ARIMA)-intervention time-series analysis. Continental United States and Hawaii (1985-May 2005). Interventions US federal regulations targeting precursors, ephedrine and pseudoephedrine, in forms used by large-scale producers were implemented in November 1989, August 1995 and October 1997. US regulations targeting precursors in forms used by small-scale producers (e.g. over-the-counter medications) were implemented in October 1996 and October 2001. Canada implemented federal precursor regulations in January 2003 and July 2003 and an essential chemical (e.g. acetone) regulation in January 2004. Monthly median methamphetamine purity series. US regulations targeting large-scale producers were associated with purity declines of 16-67 points; those targeting small-scale producers had little or no impact. Canada's precursor regulations were associated with purity increases of 13-15 points, while its essential chemical regulation was associated with a 13-point decrease. Hawaii's purity was consistently high, and appeared to vary little with the 1990s/2000s regulations. US precursor regulations targeting large-scale producers were associated with substantial decreases in continental US methamphetamine purity, while regulations targeting over-the-counter medications had little or no impact. Canada's essential chemical regulation was also associated with a decrease in continental US purity. However, Canada's precursor regulations were associated with purity increases: these regulations may have impacted primarily producers of lower-quality methamphetamine, leaving higher-purity methamphetamine on the market by default. Hawaii's well-known preference for 'ice' (high-purity methamphetamine) may have helped to

  9. Entanglement and purity of two-mode Gaussian states in noisy channels

    SciTech Connect

    Serafini, Alessio; Illuminati, Fabrizio; De Siena, Silvio; Paris, Matteo G.A.

    2004-02-01

    We study the evolution of purity, entanglement, and total correlations of general two-mode continuous variable Gaussian states in arbitrary uncorrelated Gaussian environments. The time evolution of purity, von Neumann entropy, logarithmic negativity, and mutual information is analyzed for a wide range of initial conditions. In general, we find that a local squeezing of the bath leads to a faster degradation of purity and entanglement, while it can help to preserve the mutual information between the modes.

  10. Measurement of RF Mode Purity in EC Transmission Test Line for ITER

    SciTech Connect

    Oda, Yasuhisa; Kajiwara, Ken; Takahashi, Koji; Kasugai, Atsushi; Sakamoto, Keishi

    2009-11-26

    The transmission mode purity was measured at the ITER relevant transmission line for 170 GHz ECH and CD system. The measured purity of HE{sub 11} in transmission power was 73% and the other was higher order modes. The dominant higher order mode was LP{sub 11} mode (HE{sub 21}+TE{sub 01}). To improve the mode purity, the RF beam coupling in MOU was aligned because LP{sub 11} mode is generated the offset and the tilt angle of RF beam at the waveguide inlet. After the alignment, HE{sub 11} mode purity was increased to 87%.

  11. Calculating vibrational spectra without determining excited eigenstates: Solving the complex linear equations of damped response theory for vibrational configuration interaction and vibrational coupled cluster states.

    PubMed

    Godtliebsen, Ian H; Christiansen, Ove

    2015-10-07

    It is demonstrated how vibrational IR and Raman spectra can be calculated from damped response functions using anharmonic vibrational wave function calculations, without determining the potentially very many eigenstates of the system. We present an implementation for vibrational configuration interaction and vibrational coupled cluster, and describe how the complex equations can be solved using iterative techniques employing only real trial vectors and real matrix-vector transformations. Using this algorithm, arbitrary frequency intervals can be scanned independent of the number of excited states. Sample calculations are presented for the IR-spectrum of water, Raman spectra of pyridine and a pyridine-silver complex, as well as for the infra-red spectrum of oxazole, and vibrational corrections to the polarizability of formaldehyde.

  12. Analysis of the eigenstates of a semiconductor hydrogenic washer-shaped structurally deformed nanoring: External crossed fields and stark-like effects

    NASA Astrophysics Data System (ADS)

    Castrillón, J. D.; Fulla, M. R.; Marín, J. H.; Fonnegra-García, D.; Suaza, Y. A.; Salazar-Santa, J. D.

    2017-09-01

    The eigenstates of a hydrogenic complex confined in a washer-shaped quantum ring with lateral position-controllable protuberances with a Gaussian aspect under the presence of crossed magnetic and electric probes were calculated. The size and position of the protuberances affect significantly the degree of the electron localization observable in Aharonov-Bohm and Stark-like patterns. The influence of the size of the protuberances, off-centered impurities, and in-plane electric fields on the localization of states was studied in detail. Finally, based on the electron mobility, a mechanism to detect narrow intervals of electric fields thorough the measurement of nanoscopic loop-currents as a function of the non-uniform washer-shaped quantum ring morphology was studied.

  13. Cooperative spontaneous emission of N atoms: Many-body eigenstates, the effect of virtual Lamb shift processes, and analogy with radiation of N classical oscillators

    SciTech Connect

    Svidzinsky, Anatoly A.; Chang, J.-T.; Scully, Marlan O.

    2010-05-15

    We consider collective emission of a single photon from a cloud of N two-level atoms (one excited, N-1 ground state). For a dense cloud the problem is reduced to finding eigenfunctions and eigenvalues of an integral equation. We discuss an exact analytical solution of this many-atom problem for a spherically symmetric atomic cloud. Some eigenstates decay much faster then the single atom decay rate, while the others undergo very slow decay. We show that virtual processes yield a small effect on the evolution of rapidly decaying states. However, they change the long time dynamics from exponential decay into a power-law behavior which can be observed experimentally. For trapped states virtual processes are much more important yielding additional decay channels which results in a slow decay of the otherwise trapped states. We also show that quantum mechanical treatment of spontaneous emission of weakly excited atomic ensemble is analogous to emission of N classical harmonic oscillators.

  14. Calculating vibrational spectra without determining excited eigenstates: Solving the complex linear equations of damped response theory for vibrational configuration interaction and vibrational coupled cluster states

    NASA Astrophysics Data System (ADS)

    Godtliebsen, Ian H.; Christiansen, Ove

    2015-10-01

    It is demonstrated how vibrational IR and Raman spectra can be calculated from damped response functions using anharmonic vibrational wave function calculations, without determining the potentially very many eigenstates of the system. We present an implementation for vibrational configuration interaction and vibrational coupled cluster, and describe how the complex equations can be solved using iterative techniques employing only real trial vectors and real matrix-vector transformations. Using this algorithm, arbitrary frequency intervals can be scanned independent of the number of excited states. Sample calculations are presented for the IR-spectrum of water, Raman spectra of pyridine and a pyridine-silver complex, as well as for the infra-red spectrum of oxazole, and vibrational corrections to the polarizability of formaldehyde.

  15. Quark masses and mixing in a supersymmetric left-right model with singlet quark

    NASA Astrophysics Data System (ADS)

    Babu, K. S.; Roszkowski, L.

    1989-04-01

    Recently, del Aguila, Kane and Quirós (dAKQ) have proposed an ansatz for the structure of the quark mass matrices. They assume that the quark mass eigenstates coincide with the weak-interaction eigenstates in the absence of mixing of the down-type quarks with a new vector-like singlet quark. In this paper we present a supersymmetric model which provides a natural realization of this ansatz. The model, based on a left-right gauge group, does not require any horizontal symmetry and leads to quark mass matrices more restrictive than the dAKQ ansatz. The resulting phenomenology is also discussed. We obtain upper limits on the masses of the top quark and the singlet quark D: mtop < 46GeV whereas mD < 104GeV is favored, and therefore they both should be discovered at the Tevatron.

  16. Radiochemical purity of Mo and Tc solution obtained after irradiation and dissolution of Mo-100-enriched and ultra-high-purity natural Mo disks

    SciTech Connect

    Tkac, Peter; Gromov, Roman; Chemerisov, Sergey D.; Rotsch, David A.; Vandegrift, George F.

    2016-09-01

    Four irradiations of ultra-high-purity natural Mo targets and one irradiation using 97.4% Mo-100-enriched material were performed. The purpose of these irradiations was to determine whether the presence of Sn stabilizer in the H2O2 used for the dissolution of sintered Mo disks can affect the radiochemical purity of the final K2MoO4 in 5M KOH solution. Results from radiochemical purity tests performed using thin-layer paper chromatography show that even 2– 3× excess of Sn-stabilized H2O2 typically used for dissolution of sintered Mo disks did not affect the radiochemical purity of the final product.

  17. Improving axion detection sensitivity in high purity germanium detector based experiments

    NASA Astrophysics Data System (ADS)

    Xu, Wenqin; Elliott, Steven

    2015-04-01

    Thanks to their excellent energy resolution and low energy threshold, high purity germanium (HPGe) crystals are widely used in low background experiments searching for neutrinoless double beta decay, e.g. the MAJORANA DEMONSTRATOR and the GERDA experiments, and low mass dark matter, e.g. the CDMS and the EDELWEISS experiments. A particularly interesting candidate for low mass dark matter is the axion, which arises from the Peccei-Quinn solution to the strong CP problem and has been searched for in many experiments. Due to axion-photon coupling, the postulated solar axions could coherently convert to photons via the Primakeoff effect in periodic crystal lattices, such as those found in HPGe crystals. The conversion rate depends on the angle between axions and crystal lattices, so the knowledge of HPGe crystal axis is important. In this talk, we will present our efforts to improve the HPGe experimental sensitivity to axions by considering the axis orientations in multiple HPGe crystals simultaneously. We acknowledge the support of the U.S. Department of Energy through the LANL/LDRD Program.

  18. Determination of halogens and sulfur in high-purity polyimide by IC after digestion by MIC.

    PubMed

    Krzyzaniak, Sindy R; Santos, Rafael F; Dalla Nora, Flavia M; Cruz, Sandra M; Flores, Erico M M; Mello, Paola A

    2016-09-01

    In this work, a method for sample preparation of high-purity polyimide was proposed for halogens and sulfur determination by ion chromatography (IC) with conductivity detection and, alternatively, by inductively coupled plasma mass spectrometry (ICP-MS). A relatively high polyimide mass (600mg) was completely digested by microwave-induced combustion (MIC) using 20bar of O2 and 50mmolL(-1) NH4OH as absorbing solution. These conditions allowed final solutions with low carbon content (<10mgL(-1)) and suitable pH for analysis by both IC and ICP-MS. The accuracy was evaluated using a certified reference material of polymer for Cl, Br and S and spike recovery experiments for all analytes. No statistical difference (t-test, 95% of confidence level) was observed between the results obtained for Cl, Br and S by IC after MIC and the certified values. In addition, spike recoveries obtained for F, Cl, Br, I and S ranged from 94% to 101%. The proposed method was suitable for polyimide decomposition for further determination of halogens and sulfur by IC and by ICP-MS (Br and I only). Taking into account the lack of methods and the difficulty of bringing this material into solution, MIC can be considered as a suitable alternative for the decomposition of polyimide for routine quality control of halogens and sulfur using IC or ICP-MS. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Corrosion in Supercritical carbon Dioxide: Materials, Environmental Purity, Surface Treatments, and Flow Issues

    SciTech Connect

    Sridharan, Kumar; Anderson, Mark

    2013-12-10

    separately to high purity CO{sub 2}. Task 3: Evaluation of surface treatments on the corrosion performance of alloys in supercritical CO{sub 2}: Surface treatments can be very beneficial in improving corrosion resistance. Shot peening and yttrium and aluminum surface treatments will be investigated. Shot peening refines the surface grain sizes and promotes protective Cr-oxide layer formation. Both yttrium and aluminum form highly stable oxide layers (Y{sub 2}O{sub 3} and Al{sub 2}O{sub 3}), which can get incorporated in the growing Fe-oxide layer to form an impervious complex oxide to enhance corrosion resistance. Task 4: Study of flow-assisted corrosion of select alloys in supercritical CO{sub 2} under a selected set of test conditions: To study the effects of flow-assisted corrosion, tests will be conducted in a supercritical CO{sub 2} flow loop. An existing facility used for supercritical water flow studies at the proposing university will be modified for use in this task. The system is capable of flow velocities up to 10 m/s and can operate at temperatures and pressures of up to 650°C and 20 MPa, respectively. All above tasks will be performed in conjunction with detailed materials characterization and analysis using scanning electron microscopy/energy dispersive spectroscopy (SEM-EDS), x-ray diffraction (XRD), Auger electron spectroscopy (AES) techniques, and weight change measurements. Inlet and outlet gas compositions will be monitored using gas chromatography-mass spectrometry (GCMS).

  20. Automation of the Characterization of High Purity Germanium Detectors

    NASA Astrophysics Data System (ADS)

    Dugger, Charles ``Chip''

    2014-09-01

    Neutrinoless double beta decay is a rare hypothesized process that may yield valuable insight into the fundamental properties of the neutrino. Currently there are several experiments trying to observe this process, including the Majorana DEMONSTRAOR experiment, which uses high purity germanium (HPGe) detectors to generate and search for these events. Because the event happens internally, it is essential to have the lowest background possible. This is done through passive detector shielding, as well as event discrimination techniques that distinguish between multi-site events characteristic of gamma-radiation, and single-site events characteristic of neutrinoless double beta decay. Before fielding such an experiment, the radiation response of the detectors must be characterized. A robotic arm is being tested for future calibration of HPGe detectors. The arm will hold a source at locations relative to the crystal while data is acquired. Several radioactive sources of varying energy levels will be used to determine the characteristics of the crystal. In this poster, I will present our work with the robot, as well as the characterization of data we took with an underground HPGe detector at the WIPP facility in Carlsbad, NM (2013). Neutrinoless double beta decay is a rare hypothesized process that may yield valuable insight into the fundamental properties of the neutrino. Currently there are several experiments trying to observe this process, including the Majorana DEMONSTRAOR experiment, which uses high purity germanium (HPGe) detectors to generate and search for these events. Because the event happens internally, it is essential to have the lowest background possible. This is done through passive detector shielding, as well as event discrimination techniques that distinguish between multi-site events characteristic of gamma-radiation, and single-site events characteristic of neutrinoless double beta decay. Before fielding such an experiment, the radiation response of

  1. Physical Properties and Purity of an SZE Cluster Sample Using the Atacama Cosmology Telescope

    NASA Astrophysics Data System (ADS)

    Menanteau, Felipe; ACT Collaboration

    2011-01-01

    We present optical and X-ray properties for the first confirmed galaxy cluster sample selected by the Sunyaev-Zel'dovich Effect from 148 GHz maps over 455 square degrees of sky made with the Atacama Cosmology Telescope. These maps, coupled with multi-band imaging on 4-meter-class optical telescopes, have yielded a sample of 23 galaxy clusters with redshifts between 0.118 and 1.066. Of these 23 clusters, 10 are newly discovered. The selection of this sample is approximately mass limited and essentially independent of redshift. We provide optical positions, images, redshifts and X-ray fluxes and luminosities for the full sample, and X-ray temperatures of an important subset. The mass limit of the full sample is around 8.0e14 Mo, with a number distribution that peaks around a redshift of 0.4. For the 10 highest significance SZE-selected cluster candidates, all of which are optically confirmed, the mass threshold is 1e15 Mo and the redshift range is 0.167 to 1.066. Archival observations from Chandra, XMM, and Rosat provide X-ray luminosities and temperatures that are broadly consistent with this mass threshold. Our optical follow-up procedure also allowed us to assess the purity of the ACT cluster sample. Eighty (one hundred) percent of the 148 GHz candidates with signal-to-noise ratios greater than 5.1 (5.7) are confirmed as massive clusters. The reported sample represents one of the largest SZE-selected sample of massive clusters over all redshifts within a cosmologically-significant survey volume, which will enable cosmological studies as well as future studies on the evolution, morphology, and stellar populations in the most massive clusters in the Universe. Financial support was provided by the NSF under the PIRE program (OISE-0530095).

  2. Impact of calcium on struvite crystal size, shape and purity

    NASA Astrophysics Data System (ADS)

    Le Corre, Kristell S.; Valsami-Jones, Eugenia; Hobbs, Phil; Parsons, Simon A.

    2005-10-01

    Struvite precipitation occurs spontaneously in wastewater treatment plants under conditions that are influenced by many factors including concentration of Mg 2+, NH 4+, and PO 43- ions, pH, temperature, and mixing energy. These parameters are often difficult to control and as a result struvite generates problems of scale deposits in areas such as pipes and recirculation pumps. At the same time, struvite is considered as a potentially marketable product as an alternative fertiliser. For those two reasons, it has become important to study the principles of struvite precipitation, and to assess the parameters controlling struvite crystallisation. In the present work, the influence of Ca 2+ ions on the precipitation of struvite was investigated in aqueous solutions containing Mg 2+, NH 4+, and PO 43- ions in a molar ratio 1:2:2 at room temperature and constant pH. Different laboratory experiments have been used to assess the effects of Ca 2+ ions on size, shape, and purity of the crystals formed. Tools used include particle size analysis, X-ray diffraction (XRD), and scanning electron microscopy with energy dispersive X-ray analysis (SEM-EDS). The experimental results showed that the presence of calcium in the media can affect significantly struvite crystal growth and the characteristics of the crystal produced.

  3. The regeneration games: purity and security in the Olympic city.

    PubMed

    Fussey, Pete; Coaffee, Jon; Armstrong, Gary; Hobbs, Dick

    2012-06-01

    This paper examines the wider social impacts of hosting the London 2012 Olympic Games and its 'legacy' ambitions in East London, emphasizing securitization as an inbuilt feature of the urban regeneration project. Drawing on extensive original empirical research, the paper analyses the modalities of Olympic safety and security practices within the Olympic Park itself and their wider impact, while also connecting this research to theorization and debates in urban sociology and criminology. In this complex setting, a raft of formal and informal, often subtle, regulatory mechanisms have emerged, especially as visions of social ordering focused on 'cleansing' and 'purifying' have 'leaked out' from the hyper-securitized 'sterilized' environment of the Olympic Park and become embedded within the Olympic neighbourhood. In such complex circumstances, applying Douglas' (1966) work on purity and danger to the spatial realm provides a key conceptual framework to understand the form and impact of such processes. The imposition of order can be seen to not only perform 'cleansing' functions, but also articulate multiple symbolic, expressive and instrumental roles. © London School of Economics and Political Science 2012.

  4. D2 and CD4 Purity Effects on CD Ablators

    SciTech Connect

    Cook, R C; Nikroo, A

    2004-01-09

    The question of how the isotopic purity of the feed gases D{sub 2} and CD{sub 4} used to make CD ablators at GA effects the extinction coefficient in the region of wavenumber 2900 cm{sup -1} ({lambda} = 3.45 {micro}m) is addressed below. The answer is at best incomplete; this is only an interim evaluation. What is clear is that using ultra-pure D{sub 2} is required to lower the ''CH'' impurity peak at 2900 cm{sup -1}. Perhaps using ultra-pure CD{sub 4} also helps, though the evidence for this is mixed. A closer look at the results raises other questions, however, and these are discussed below. Though solving these questions is unlikely to reduce the extinction coefficient in the region of 2900 cm{sup -1} below about 10 cm{sup -1}, this work will lead to a better understanding of the deposition of CH/CD GDP, and that is certainly worthwhile.

  5. Permeation of oxygen through high purity, large grain silver

    NASA Technical Reports Server (NTRS)

    Outlaw, R. A.; Peregoy, W. K.; Hoflund, Gar B.

    1987-01-01

    The permeation of high purity, large grain Ag membranes by oxygen has been studied over the temperature range 400 to 800 C. The permeability was found to be quite linear and repeatable, but the magnitude was 3.2 times smaller than that determined by past research. Since previous investigators studied substantially less pure Ag and conducted experiments within much poorer vacuum environments (which indicates that their grain boundary density was much greater), the data presented here suggest oxygen transport through the membrane is primarily by grain boundary diffusion. The diffusivity measurements were found to exhibit two distinct linear regions, one above and one below a critical temperature of 630 C. The high-temperature data have an activation energy (11.1 kcal/mole) similar to that reported by others, but the low-temperature data have a higher activation energy (15.3 kcal/mole), which can be explained by impurity trapping in the grain boundaries. Vacuum desorption of the oxygen-saturated Ag was found to occur at a threshold of 630 C, which is consistent with the onset of increased mobility within the grain boundaries.

  6. PERFORMANCES OF HIGH PURITY NIOBIUM CAVITIES WITH DIFFERENT GRAIN SIZES

    SciTech Connect

    Gianluigi Ciovati; Peter Kneisel; Ganapati Myneni; Swapan Chattopadhyay

    2006-08-21

    Grain boundaries have for some time been suspected of influencing the performance of RF cavities made from high purity niobium by limiting the temperature dependent BCS surface resistance to a residual resistance because of impurity segregation and by causing field limitations due to flux penetration. We have carried out a comparative study of the RF behavior of 2.2 GHz TM{sub 010} cavities of identical shape, fabricated from single crystal niobium, niobium of grain sizes of the order of several cm{sup 2} and standard poly-crystalline material. All the cavities were treated with buffered chemical polishing (BCP), post-purified at 1250 ?C and ?in-situ? baked at 120 C. This contribution reports about the results of the measurements of the temperature dependence of the surface resistance Rs(T) and the Q0 vs. Eacc behavior at 2 K. From the analysis of the Rs(T) data at low RF fields material parameters such as gap value, mean free path and residual resistance could be extracted. The dependence of the Q-value on RF field was analyzed with respect to the medium field Q-slope, Q-drop at high fields and the quench fields. The best performance resulted in a breakdown field of {approx}165 mT, corresponding to an accelerating gradient of E{sub acc} {approx} 38 MV/m.

  7. PERFORMANCES OF HIGH PURITY NIOBIUM CAVITIES WITH DIFFERENT GRAIN SIZES

    SciTech Connect

    Gianluigi Ciovati; Peter Kneisel; Ganapati Myneni; Ganapati Rao Myneni; Ganapati Rao Myneni; Swapan Chattopadhyay

    2006-08-04

    Grain boundaries have for some time been suspected of influencing the performance of RF cavities made from high purity niobium by limiting the temperature dependent BCS surface resistance to a residual resistance because of impurity segregation and by causing field limitations due to flux penetration. We have carried out a comparative study of the RF behavior of 2.2 GHz TM010 cavities of identical shape, fabricated from single crystal niobium, niobium of grain sizes of the order of several cm2 and standard poly-crystalline material. All the cavities were treated with buffered chemical polishing (BCP), post-purified at 1250 C and ''in-situ'' baked at 120 C. This contribution reports about the results of the measurements of the temperature dependence of the surface resistance Rs(T) and the Q0 vs. Eacc behavior at 2 K. From the analysis of the Rs(T) data at low RF fields material parameters such as gap value, mean free path and residual resistance could be extracted. The dependence of the Q-value on RF field was analyzed with respect to the medium field Q-slope, ''Q-drop'' at high fields and the ''quench'' fields. The best performance resulted in a breakdown field of {approx} 165 mT, corresponding to an accelerating gradient of Eacc {approx} 38 MV/m.

  8. Phase purity of sol-gel-derived hydroxyapatite ceramic.

    PubMed

    Hsieh, M F; Perng, L H; Chin, T S; Perng, H G

    2001-10-01

    Calcium oxide was reported in the sol-gel-derived hydroxyapatite (HA) as an unavoidable major impurity. In this study phase purity of HA synthesized by sol-gel route was explored using precursors of calcium nitrate tetrahydrate and triethyl phosphate. Two different drying methods, the fast drying of as-prepared precursors and the slow drying of aged precursors were adopted as major processing variables. The dried gels were subsequently calcined up to 600 degrees C. In the calcined powder from fast-dried gel, X-ray diffraction (XRD) patterns revealed an intense CaO peak. For the slow-dried gel, thermogravimetric analysis revealed a 2-step weight-loss behavior during heating. XRD analysis of the calcined powder, corresponding to the second weight-loss step, showed major peaks of hydroxyapatite and a very weak CaO peak. P-31 NMR analysis indicated formation of calcium phosphate complex during aging. Complete incorporation of Ca(NO3)2 into the complex due to proper aging therefore diminishes CaO formation. It was also found that the minor CaO derived in the slow drying method can be easily and completely washed out just by distilled water.

  9. Observing bulk diamond spin coherence in high-purity nanodiamonds

    NASA Astrophysics Data System (ADS)

    Knowles, Helena S.; Kara, Dhiren M.; Atatüre, Mete

    2014-01-01

    Nitrogen-vacancy (NV) centres in diamond are attractive for research straddling quantum information science, nanoscale magnetometry and thermometry. Whereas ultrapure bulk diamond NVs sustain the longest spin coherence times among optically accessible spins, nanodiamond NVs exhibit persistently poor spin coherence. Here we introduce high-purity nanodiamonds accommodating record-long NV coherence times, >60 μs, observed through universal dynamical decoupling. We show that the main contribution to decoherence comes from nearby nitrogen impurities rather than surface states. We protect the NV spin free precession, essential to d.c. magnetometry, by driving solely these impurities into the motional narrowing regime. This extends the NV free induction decay time from 440 ns, longer than that in type Ib bulk diamond, to 1.27 μs, which is comparable to that in type IIa (impurity-free) diamond. These properties allow the simultaneous exploitation of both high sensitivity and nanometre resolution in diamond-based emergent quantum technologies.

  10. Progressive band processing of fast iterative pixel purity index

    NASA Astrophysics Data System (ADS)

    Li, Yao; Chang, Chein-I.

    2016-05-01

    Fast Iterative Pixel Purity Index (FIPPI) was previously developed to address two major issues arising in PPI which are the use of skewers whose number must be determined by a priori and inconsistent final results which cannot be reproduced. Recently, a new concept has been developed for hyperspectral data communication according to Band SeQuential (BSQ) acquisition format in such a way that bands can be collected band by band. By virtue of BSQ users are able to develop Progressive Band Processing (PBP) for hyperspectral imaging algorithms so that data analysts can observe progressive profiles of inter-band changes among bands. Its advantages have been justified in several applications, anomaly detection, constrained energy minimization, automatic target generation process, orthogonal subspace projection, PPI, etc. This paper further extends PBP to FIPPI. The idea to implement PBP-FIPPI is to use two loops specified by skewers and bands to process FIPPI. Depending upon which one is implemented in the outer loop two different versions of PBP-FIPPI can be designed. When the outer loop is iterated band by band, it is called to be called Progressive Band Processing of FIPPI (PBP-FIPPI). When the outer loop is iterated by growing skewers, it is called Progressive Skewer Processing of FIPPI (PSP-FIPPI). Interestingly, both versions provide different insights into the design of FIPPI but produce close results.

  11. Animal Sex: Purity Education and the Naturalization of the Abstinence Agenda

    ERIC Educational Resources Information Center

    Sethna, Christabelle

    2010-01-01

    An early-twentieth-century movement for social purity in England, Canada and the United States aimed to eradicate prostitution, the double standard of sexual morals and their dreaded corollary, the venereal diseases. Social purists suggested that "purity education" for children was the best pedagogical prophylaxis against such…

  12. Animal Sex: Purity Education and the Naturalization of the Abstinence Agenda

    ERIC Educational Resources Information Center

    Sethna, Christabelle

    2010-01-01

    An early-twentieth-century movement for social purity in England, Canada and the United States aimed to eradicate prostitution, the double standard of sexual morals and their dreaded corollary, the venereal diseases. Social purists suggested that "purity education" for children was the best pedagogical prophylaxis against such…

  13. Recent Rhetorics of Purity in the Visual Arts. Infection, Dissemination, Genealogy.

    ERIC Educational Resources Information Center

    Cheetham, Mark A.

    1997-01-01

    Analyzes the medical discourses of infection, purity, and impurity and how these relate to the manipulation of images and ideas inherent in modern art. Argues that various concepts of purity (both in form and as a metaphorical subject) continue to exert powerful influences on artists in the 20th century. (MJP)

  14. Human Newborn Color Vision: Measurement with Chromatic Stimuli Varying in Excitation Purity.

    ERIC Educational Resources Information Center

    Adams, Russell J.; Courage, Mary L.

    1998-01-01

    Habituated 180 neonates to white lights of varying luminance and tested for recovery of habituation to green, yellow, or red lights varying in excitation purity. Found that newborns discriminated chromatic stimuli from white only when excitation purity exceeded levels much higher than those for adults. Results reinforce view that neonates' vision…

  15. The use of differential scanning calorimetry for the purity verification of pharmaceutical reference standards.

    PubMed

    Mathkar, S; Kumar, S; Bystol, A; Olawoore, K; Min, D; Markovich, R; Rustum, A

    2009-04-05

    Reference standards are routinely used in pharmaceutical industry to determine strength, content, and the quality of drug products, active pharmaceutical ingredients (API), preservatives, antioxidants and excipients. Traditionally, chromatographic techniques such as High Performance Liquid Chromatography (HPLC) and Gas Chromatography (GC) in conjunction with other analytical techniques have been used to determine the purity and strength of a specific lot of a compound for the purpose of qualifying the lot to use as a reference standard. The assigned purity of the reference standard for a wide variety of compounds can be verified using an absolute method such as Differential Scanning Calorimetry (DSC). In this paper, purity of 16 reference standards was determined by DSC and the results were then compared to the purity values that were obtained using HPLC and other analytical techniques. The results indicate that the purity obtained from DSC analysis is comparable to the chromatographic purity for organic compounds that are at least 98% pure. Use of DSC for purity determination is not appropriate if a compound lacks sharp melting point, decomposes in the defined temperature range or exhibits other thermal event(s) which interfere with the melting point of the compound. The use of DSC as an alternative and or complementary method to verify the purity of a compound as part of the pharmaceutical reference standard certification process is discussed.

  16. Preparation of high purity lanthanum compounds for use in fluoride optical fibers

    SciTech Connect

    Ewing, K.J.; Buckner, L.; Jaganathan, J.; Ginther, R.; Aggarwal, I.D. . Optical Sciences Div.)

    1989-02-01

    The preparation of ultra-pure lanthanum nitrate by co-precipitation is described. Preparation of high purity lanthanum carbonate from the pure nitrate is also described. Hydrofluorination of pure lanthanum carbonate produces high purity lanthanum fluoride used in the preparation of heavy metal fluoride glasses.

  17. Human Newborn Color Vision: Measurement with Chromatic Stimuli Varying in Excitation Purity.

    ERIC Educational Resources Information Center

    Adams, Russell J.; Courage, Mary L.

    1998-01-01

    Habituated 180 neonates to white lights of varying luminance and tested for recovery of habituation to green, yellow, or red lights varying in excitation purity. Found that newborns discriminated chromatic stimuli from white only when excitation purity exceeded levels much higher than those for adults. Results reinforce view that neonates' vision…

  18. Nucleon axial form factors using Nf=2 twisted mass fermions with a physical value of the pion mass

    NASA Astrophysics Data System (ADS)

    Alexandrou, C.; Constantinou, M.; Hadjiyiannakou, K.; Jansen, K.; Kallidonis, C.; Koutsou, G.; Vaquero Aviles-Casco, A.

    2017-09-01

    We present results on the nucleon axial and induced pseudoscalar form factors using an ensemble of two degenerate twisted mass clover-improved fermions with mass yielding a pion mass of mπ=130 MeV . We evaluate the isovector and the isoscalar, as well as the strange and the charm axial form factors. The disconnected contributions are evaluated using recently developed methods that include deflation of the lower eigenstates, allowing us to extract the isoscalar, strange, and charm axial form factors. We find that the disconnected quark loop contributions are nonzero and particularly large for the induced pseudoscalar form factor.

  19. Prognostic Relevance of Tumor Purity and TERT Promoter Mutations on MGMT Promoter Methylation in Glioblastoma.

    PubMed

    Schulze Heuling, Eva; Knab, Felix; Radke, Josefine; Eskilsson, Eskil; Martinez-Ledesma, Emmanuel; Koch, Arend; Czabanka, Marcus; Dieterich, Christoph; Verhaak, Roel G; Harms, Christoph; Euskirchen, Philipp

    2017-02-01

    Promoter methylation status of O-6-methylguanine-DNA methyltransferase (MGMT), a DNA repair enzyme, is a critical biomarker in glioblastoma multiforme (GBM) as treatment decisions and clinical trial inclusion rely on its accurate assessment. However, interpretation of results is complicated by poor inter-assay reproducibility as well as weak a correlation between methylation status and expression levels of MGMT. The present study systematically investigates the influence of tumor purity on tissue subjected to MGMT analysis. A quantitative, allele-specific real-time PCR (qAS-PCR) assay was developed to determine genotype and mutant allele frequency of telomerase promoter (pTERT) mutations as a direct measure of tumor purity. We studied tumor purity, pTERT mutation by Sanger sequencing, MGMT methylation by pyrosequencing, IDH1 mutation status, and clinical parameters in a cohort of high-grade gliomas (n=97). The qAS-PCR reliably predicted pTERT genotype and tumor purity compared with independent methods. Tumor purity positively and significantly correlated with the extent of methylation in MGMT methylated GBMs. Extent of MGMT methylation differed significantly with respect to pTERT mutation hotspot (C228T vs. C250T). Interestingly, frontal lobe tumors showed greater tumor purity than those in other locations. Above all, tumor purity was identified as an independent prognostic factor in GBM. In conclusion, we determined mutual associations of tumor purity with MGMT methylation and pTERT mutations and found that the extent of MGMT methylation reflects tumor purity. In turn, tumor purity is prognostic in IDH1 wildtype GBM.

  20. Synthesis of high purity sinterable silicon carbide powder

    SciTech Connect

    Boecker, W.D.; Mehosky, B.L.; Rogers, R.S.C.; Storm, R.S.; Venkateswaran, V. . Structural Ceramics Div.)

    1989-11-01

    High purity, submicron silicon carbide powders were produced via gas phase synthesis using a hydrogen/argon plasma. Two test facilities were constructed, a bench-scale unit and a larger pilot scale reactor. Three candidate silicon sources were evaluated:silicon tetrachloride (SiCl{sub 4}). dimethyldichlorosilane (CH{sub 3}){sub 2}(SiCl{sub 2}) and methyltrichlorosilane (CH{sub 3}SiCl{sub 3}). Product powders were evaluated on the basis of pressureless sinterability, surface area, agglomeration, particle size distribution, phase distribution and chemistry. Three commercial powders, Starck A10, Starck B10, and Carborundum submicron alpha silicon carbide, were also evaluated for comparison to the product powders. Powders were reproducibly synthesized at a rate of one pound per hour for standard run times of five hours. Product powders exhibited chemical and physical properties equal to or exceeding the commercial powders evaluated. In limited attempts to pressureless sinter the product powders, densities of 91% of theoretical were obtained with as-produced powder. Post-processing permitted densities in excess of 97% of theoretical. X-ray diffraction of the product indicates that the product powders are primarily beta poly-types, with traces of alpha present. Increased production rates to a target level of seven pounds per hour were not possible due to current transients produced by the pilot scale power supply. Extensive unsuccessful efforts to reduce or eliminate the transients are described. Low recovered product yields resulted from a failure of a product collection filter that was not discovered until the completion of the project.

  1. Chemical purity and toxicology of pigments used in tattoo inks.

    PubMed

    Petersen, Henrik; Lewe, Dirk

    2015-01-01

    The safety of tattoo inks has obviously increased in Europe since the existence of European Union Resolution ResAP(2008)1, which resulted in the improved quality control of pigment raw materials due to the definition of impurity limits that manufacturers can refer to. High-performance pigments are mostly used in tattoo inks, and these pigments are supposed to be chemically inert and offer high light fastness and low migration in solvents. However, these pigments were not developed or produced for applications involving long-term stay in the dermis or contact with bodily fluids. Therefore, these pigments often do not comply with the purity limits of the resolution; however, it is required that every distributed tattoo ink does not contain aromatic amines and not exceed the limits of heavy metals or polycyclic aromatic hydrocarbons. Current toxicity studies of pigments underline that no ecotoxicological threat to human health or to the environment should be expected. However, the pigment as well as its impurities and coating materials must be considered. In order to evaluate the safety of pigments according to their impurities, two different validated sample preparation methods are necessary: (1) simulation of their long-term stay in the bodily fluid of the dermis and (2) simulation of cleavage due to laser removal or ultraviolet exposure. The development of standardized, validated and well-adapted methods for this application has to be part of prospective efforts. Concerning legislation, it might be appropriate that the first regulative approaches be based on those of cosmetics. © 2015 S. Karger AG, Basel.

  2. Spectroscopic Determination of Trace Contaminants in High-Purity Oxygen

    NASA Technical Reports Server (NTRS)

    Hornung, Steven

    2013-01-01

    Oxygen used for extravehicular activities (EVAs) must be free of contaminants because a difference in a few tenths of a percent of argon or nitrogen content can mean significant reduction in available EVA time. These inert gases build up in the extravehicular mobility unit because they are not metabolized or scrubbed from the atmosphere. A prototype optical emission technique capable of detecting argon and nitrogen below 0.1% in oxygen has been developed. This instrument uses a glow discharge in reduced-pressure gas to produce atomic emission from the species present. Because the atomic emission lines from oxygen, nitrogen, and argon are discrete, and in many cases well-separated, trace amounts of argon and nitrogen can be detected in the ultraviolet and visible spectrum. This is a straightforward, direct measurement of the target contaminants, and may lend itself to a device capable of on-orbit verification of oxygen purity. A glow discharge is a plasma formed in a low-pressure (1 to 10 Torr) gas cell between two electrodes. Depending on the configuration, voltages ranging from 200 V and above are required to sustain the discharge. In the discharge region, the gas is ionized and a certain population is in the excited state. Light is produced by the transitions from the excited states formed in the plasma to the ground state. The spectrum consists of discrete, narrow emission lines for the atomic species, and broader peaks that may appear as a manifold for molecular species such as O2 and N2, the wavelengths and intensities of which are a characteristic of each atom. The oxygen emission is dominated by two peaks at 777 and 844 nm.

  3. High-purity semi-insulating 4H-SiC for microwave device applications

    NASA Astrophysics Data System (ADS)

    Jenny, J. R.; Malta, D. P.; Müller, St G.; Powell, A. R.; Tsvetkov, V. F.; Hobgood, H. Mcd; Glass, R. C.; Carter, C. H., Jr.

    2003-05-01

    High-purity, semi-insulating (HPSI) 4H-SiC crystals with diameters up to 75 mm have been grown by the seeded sublimation technique without the intentional introduction of elemental deep-level dopants, such as vanadium. Wafers cut from these crystals exhibit homogeneous activation energies near mid gap and thermally stable semi-insulating (SI) behavior (>109 ohm-cm) throughout device processing. Secondary ion mass spectroscopy, deep-level transient spectroscopy, optical admittance spectroscopy, and electron paramagnetic resonance data suggest that the SI behavior originates from several deep levels associated with intrinsic point defects. Micropipe densities in HPSI substrates have been demonstrated to be as low as 10 cm-2 in 2-in. substrates, and the room-temperature thermal conductivity of this material is near the theoretical maximum of 5 W/cm·K for 4H-SiC. Devices fabricated on these HPSI wafers do not exhibit any substrate related back-gating effects and have power densities as high as 5.2 W/mm with 63% power added efficiency.

  4. High-purity biodiesel production from microalgae and added-value lipid extraction: a new process.

    PubMed

    Veillette, M; Giroir-Fendler, A; Faucheux, N; Heitz, M

    2015-01-01

    A new process was tested in order to produce and purify biodiesel from microalgae lipids and to recover unsaponifiable (added-value) lipids. This process is a two-step biodiesel production including a saponification reaction step followed by an esterification reaction step. The process includes a recovery of the unsaponified lipids between both reaction steps. Among the conditions tested, the following conditions were found to be the best: temperature for both steps (90 °C), saponification time (30 min), esterification time (30 min), sulfuric acid/potassium hydroxide (1.21, w/w), and methanol-lipid ratio (13.3 mL/g). Under these conditions, the fatty acid methyl ester (FAME) yield and the biodiesel purity were, respectively, 32% (g FAME/g lipid) and 77% (g FAME/g biodiesel). This study also showed that the two-step biodiesel process allows a FAME mass composition rich in palmitate (27.9-29.4 wt%), palmitoleate (24.9-26.0 wt%), elaidate (14.8-15.2 wt%), and myristate (12.1-13.0 wt%).

  5. Increased Yield of High Purity Recombinant Human Interferon-γ Utilizing Reversed Phase Column Chromatography

    PubMed Central

    Reddy, Praveen K.; Reddy, Srinivasa G.; Narala, Venkata R.; Majee, Sangita S.; Konda, Sudhakar; Gunwar, Sripad; Reddy, Raju C.

    2007-01-01

    Increasing therapeutic applications for recombinant human interferon-γ (rhIFN-γ), an antiviral proinflammatory cytokine, has broadened interest in optimizing methods for its production and purification. We describe a reversed phase chromatography (RPC) procedure using Source-30™ matrix in the purification of rhIFN-γ from Escherichia coli that results in a higher yield than previously reported. The purified rhIFN-γ monomer from the RPC column is refolded in Tris buffer. Optimal refolding occurs at protein concentrations between 50–100 μg/ml. This method yields greater than 90% of the dimer form with a yield of 40 mg g−1 cell mass. Greater than 99% purity is achieved with further purification over a Superdex G-75 column to obtain specific activities of from 2 to 4 × 107 IU/mg protein as determined via cytopathic antiviral assay. The improved yield of rhIFN-γ in a simple chromatographic purification procedure promises to enhance the development and therapeutic application of this biologically potent molecule. PMID:17049266

  6. Compensation mechanism in high purity semi-insulating 4H-SiC

    NASA Astrophysics Data System (ADS)

    Mitchel, W. C.; Mitchell, William D.; Smith, H. E.; Landis, G.; Smith, S. R.; Glaser, E. R.

    2007-03-01

    A study of deep levels in high purity semi-insulating 4H-SiC has been made using temperature dependent Hall effect (TDH), thermal and optical admittance spectroscopies, and secondary ion mass spectrometry (SIMS). Thermal activation energies from TDH varied from a low of 0.55eV to a high of 1.65eV. All samples studied showed n-type conduction with the Fermi level in the upper half of the band gap. Fits of the TDH data to different charge balance equations and comparison of the fitting results with SIMS measurements indicated that the deep levels are acceptorlike even though they are in the upper half of the band gap. Carrier concentration measurements indicated that the deep levels are present in concentrations in the low 1015cm-3 range, while SIMS results demonstrate nitrogen and boron concentrations in the low to mid-1015-cm-3 range. The results suggest that compensation in this material is a complex process involving multiple deep levels.

  7. Assessment of snake antivenom purity by comparing physicochemical and immunochemical methods.

    PubMed

    Segura, Alvaro; Herrera, María; Villalta, Mauren; Vargas, Mariángela; Gutiérrez, José María; León, Guillermo

    2013-03-01

    Purity is a characteristic that, together with effectiveness and safety, must be tested to determine the quality of biopharmaceutical products. In therapeutic immunoglobulins, such as human intravenous immunoglobulin (IVIG), purity is evaluated on the basis of physicochemical properties, and is usually assessed by chromatography and electrophoresis. However, in the case of antivenoms these methods fail to discriminate between antibodies towards venom antigens, which constitute the active substance, and antibodies towards non-venom antigens, which are the major impurities in most of the current formulations. The assessment of this aspect of purity requires the use of the immunochemical methods. In this study, it was demonstrated that antivenoms showing physicochemical purity higher than 90% might present immunochemical purity lower than 40%. It is proposed that a comprehensive analysis of antivenom purity should combine physicochemical and immunochemical parameters. In addition, these results are crucial to decide the more appropriate strategies to improve antivenom purity. Taking into account that the current methods of antivenom purification remove most non-antibodies proteins, we propose that efforts must be primarily directed to the improvement of immunization protocols to enhance the antibody response towards venom components in hyperimmunized animals, and secondarily, in the realm of immunoglobulin purification technology. Copyright © 2012 The International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

  8. High purity isolation and quantification of semiconducting carbon nanotubes via column chromatography.

    PubMed

    Tulevski, George S; Franklin, Aaron D; Afzali, Ali

    2013-04-23

    The isolation of semiconducting carbon nanotubes (CNTs) to ultrahigh (ppb) purity is a prerequisite for their integration into high-performance electronic devices. Here, a method employing column chromatography is used to isolate semiconducting nanotubes to 99.9% purity. The study finds that by modifying the solution preparation step, both the metallic and semiconducting fraction are resolved and elute using a single surfactant system, allowing for multiple iterations. Iterative processing enables a far more rapid path to achieving the level of purities needed for high performance computing. After a single iteration, the metallic peak in the absorption spectra is completely attenuated. Although absorption spectroscopy is typically used to characterize CNT purity, it is found to be insufficient in quantifying solutions of high purity (>98 to 99%) due to low signal-to-noise in the metallic region of ultrahigh purity solutions. Therefore, a high throughput electrical testing method was developed to quantify the degree of separation by characterizing ∼4000 field-effect transistors fabricated from the separated nanotubes after multiple iterations of the process. The separation and characterization methods described here provide a path to produce the ultrahigh purity semiconducting CNT solutions needed for high performance electronics.

  9. High-purity isolation of anthocyanins mixtures from fruits and vegetables--a novel solid-phase extraction method using mixed mode cation-exchange chromatography.

    PubMed

    He, Jian; Giusti, M Monica

    2011-11-04

    Research on biological activity of anthocyanins requires the availability of high purity materials. However, current methods to isolate anthocyanins or anthocyanin mixtures are tedious and expensive or insufficient for complete isolation. We applied a novel cation-exchange/reversed-phase combination solid-phase extraction (SPE) technique, and optimized the use of water/organic buffer mobile phases to selectively separate anthocyanins. Crude extracts of various representative anthocyanin sources were purified with this technique and compared to 3 commonly used SPE techniques: C(18), HLB, and LH-20. Purified anthocyanin fractions were analyzed with high performance liquid chromatography (HPLC) coupled to photodiode array (PDA) and mass spectrometry (MS) detectors and by Fourier transform infrared (FT-IR) spectroscopy. The UV-visible chromatograms quantitatively demonstrated that our novel technique achieved significantly higher (P<0.05) anthocyanin purity than the C(18) cartridge, the next best method, for 11 of the 12 anthocyanin sources tested. Among them, eight were purified to greater than 99% purity (based on UV-visible chromatograms). The new method efficiently removed non-anthocyanin phenolics. MS and FT-IR results semi-quantitatively confirmed extensive reduction of impurities. Due to strong ionic interaction, our sorbent capacity was superior to others, resulting in the highest throughput and least use of organic solvents. This new methodology for isolation of anthocyanin mixtures drastically increased purity and efficiency while maintaining excellent recovery rate and low cost. The availability of high purity anthocyanin mixtures will facilitate anthocyanin studies and promote the application of anthocyanins in the food and nutraceutical industries. Copyright © 2011 Elsevier B.V. All rights reserved.

  10. Loop suppressed light fermion masses with U (1 )R gauge symmetry

    NASA Astrophysics Data System (ADS)

    Nomura, Takaaki; Okada, Hiroshi

    2017-07-01

    We propose a model with a two-Higgs doublet, where quark and charged-lepton masses in the first and second families are induced at one-loop level, and neutrino masses are induced at the two-loop level. In our model, we introduce an extra U (1 )R gauge symmetry that plays a crucial role in achieving desired terms in no conflict with anomaly cancellation. We show the mechanism to generate fermion masses, the resultant mass matrices, and Yukawa interactions in mass eigenstates, and we discuss several interesting phenomenologies such as the muon anomalous magnetic dipole moment and the dark matter candidate that arise from this model.

  11. A modified method for isolating mouse islets of an adequate quality, quantity, and purity.

    PubMed

    Xu, Jiejie; Peng, Baogang; Zhang, Caiyun; Xu, Jiwei; Ma, Yi; Lu, Xinjun

    2017-08-01

    Mouse islets are widely used in diabetes research. Thus an adequate quality, quantity, and purity of islets are needed for high-quality investigations. We performed a combination of filtration and density gradient separation and optimized many steps in the islet isolation procedure, including perfusion, digestion, and purification. Our results show that an increased quality, quantity, and purity of isolated islets can be achieved using these modifications. Moreover, this method can guarantee maximal recovery and purity of the isolated islets and is easy to perform with practice.

  12. Conditional purity and quantum correlation measures in two qubit mixed states

    NASA Astrophysics Data System (ADS)

    Rebón, L.; Rossignoli, R.; Varga, J. J. M.; Gigena, N.; Canosa, N.; Iemmi, C.; Ledesma, S.

    2016-11-01

    We analyze and show experimental results of the conditional purity, the quantum discord and other related measures of quantum correlation in mixed two-qubit states constructed from a pair of photons in identical polarization states. The considered states are relevant for the description of spin pair states in interacting spin chains in a transverse magnetic field. We derive clean analytical expressions for the conditional local purity and other correlation measures obtained as a result of a remote local projective measurement, which are fully verified by the experimental results. A simple exact expression for the quantum discord of these states in terms of the maximum conditional purity is also derived.

  13. The Hydrometallurgical Extraction and Recovery of High-Purity Silver

    NASA Astrophysics Data System (ADS)

    Hoffmann, James E.

    2012-06-01

    -bearing inputs, will be described in detail to demonstrate how typical chemical engineering unit process and unit operations have supplanted classic smelting and fire refining techniques. The Kennecott Copper Company, which has operated a hydrometallurgical circuit successfully for the recovery of high-purity silver from the slimes wet chlorination residue, has permitted me to provide some operation information and results using the technology. Both Phelps Dodge and Kennecott should be recognized for their forward-looking attitude in undertaking the conversion of conceptual chemistry into successful, full-scale plants. The process as employed at Phelps Dodge is discussed at length in reference (J.E. Hoffmann and B. Wesstrom: Hydrometallurgy, 1994, vol. 94, pp. 69-105).

  14. A light hydrocarbon fuel processor producing high-purity hydrogen

    NASA Astrophysics Data System (ADS)

    Löffler, Daniel G.; Taylor, Kyle; Mason, Dylan

    This paper discusses the design process and presents performance data for a dual fuel (natural gas and LPG) fuel processor for PEM fuel cells delivering between 2 and 8 kW electric power in stationary applications. The fuel processor resulted from a series of design compromises made to address different design constraints. First, the product quality was selected; then, the unit operations needed to achieve that product quality were chosen from the pool of available technologies. Next, the specific equipment needed for each unit operation was selected. Finally, the unit operations were thermally integrated to achieve high thermal efficiency. Early in the design process, it was decided that the fuel processor would deliver high-purity hydrogen. Hydrogen can be separated from other gases by pressure-driven processes based on either selective adsorption or permeation. The pressure requirement made steam reforming (SR) the preferred reforming technology because it does not require compression of combustion air; therefore, steam reforming is more efficient in a high-pressure fuel processor than alternative technologies like autothermal reforming (ATR) or partial oxidation (POX), where the combustion occurs at the pressure of the process stream. A low-temperature pre-reformer reactor is needed upstream of a steam reformer to suppress coke formation; yet, low temperatures facilitate the formation of metal sulfides that deactivate the catalyst. For this reason, a desulfurization unit is needed upstream of the pre-reformer. Hydrogen separation was implemented using a palladium alloy membrane. Packed beds were chosen for the pre-reformer and reformer reactors primarily because of their low cost, relatively simple operation and low maintenance. Commercial, off-the-shelf balance of plant (BOP) components (pumps, valves, and heat exchangers) were used to integrate the unit operations. The fuel processor delivers up to 100 slm hydrogen >99.9% pure with <1 ppm CO, <3 ppm CO 2. The

  15. MassToMI-A Mathematica package for an automatic Mass Insertion expansion

    NASA Astrophysics Data System (ADS)

    Rosiek, Janusz

    2016-04-01

    We present a Mathematica package designed to automatize the expansion of transition amplitudes calculated in the mass eigenstates basis (i.e. expressed in terms of physical masses and mixing matrices) into series of ;mass insertions;, defined as off-diagonal entries of mass matrices in Lagrangian before diagonalization and identification of the physical states. The algorithm implemented in this package is based on the general ;Flavor Expansion Theorem; proven in Dedes et al. (2015). The supplied routines are able to automatically analyze the structure of the amplitude, identify the parts which could be expanded and expand them to any required order. They are capable of dealing with amplitudes depending on both scalar or vector (Hermitian) and Dirac or Majorana fermion (complex) mass matrices. The package can be downloaded from the address www.fuw.edu.pl/masstomi.

  16. Large-scale isolation of high-purity anthocyanin monomers from mulberry fruits by combined chromatographic techniques.

    PubMed

    Chen, Yao; Du, Fang; Wang, Wei; Li, Qian; Zheng, Daheng; Zhang, Weijie; Zhao, Ting; Mao, Guanghua; Feng, Weiwei; Wu, Xiangyang; Yang, Liuqing

    2017-09-01

    Anthocyanins have attracted attention over the past several decades because of their beneficial health effects. In this research, a strategy combining column chromatography and high-speed countercurrent chromatography was developed for the separation of high-purity anthocyanin monomers from mulberry fruits. After purification using Amberlite XAD-7HP column with 80% ethanol (0.1% HCl), a fraction of anthocyanins mixtures with a purity of 68.6% was obtained. High-speed countercurrent chromatography with a biphasic solvent system of n-butanol/methyl tert-butyl ether/acetonitrile/water/trifluoroacetic acid (30:10:10:50:0.05, v/v) was used to separate the anthocyanin monomers. Three monomers of delphinidin-3-O-rutinoside, cyanidin-3-O-rutinoside, and cyanidin-3-O-glucoside were obtained, and identified by (1) H and (13) C NMR spectroscopy and high-performance liquid chromatography with electrospray ionization-mass spectrometry. The method developed in this work can be used to conduct large-scale separations of anthocyanin monomers from mulberry fruits and other plants. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Manifesting the evolution of eigenstates from quantum billiards to singular billiards in the strongly coupled limit with a truncated basis by using RLC networks

    NASA Astrophysics Data System (ADS)

    Tuan, P. H.; Liang, H. C.; Tung, J. C.; Chiang, P. Y.; Huang, K. F.; Chen, Y. F.

    2015-12-01

    The coupling interaction between the driving source and the RLC network is explored and characterized as the effective impedance. The mathematical form of the derived effective impedance is verified to be identical to the meromorphic function of the singular billiards with a truncated basis. By using the derived impedance function, the resonant modes of the RLC network can be divided into the open-circuit and short-circuit states to manifest the evolution of eigenvalues and eigenstates from closed quantum billiards to the singular billiards with a truncated basis in the strongly coupled limit. The substantial differences of the wave patterns between the uncoupled and strongly coupled eigenmodes in the two-dimensional wave systems can be clearly revealed with the RLC network. Finally, the short-circuit resonant states are exploited to confirm that the experimental Chladni nodal-line patterns in the vibrating plate are the resonant modes subject to the strong coupling between the oscillation system and the driving source.

  18. Algebraic function operator expectation value based quantum eigenstate determination: A case of twisted or bent Hamiltonian, or, a spatially univariate quantum system on a curved space

    SciTech Connect

    Baykara, N. A.

    2015-12-31

    Recent studies on quantum evolutionary problems in Demiralp’s group have arrived at a stage where the construction of an expectation value formula for a given algebraic function operator depending on only position operator becomes possible. It has also been shown that this formula turns into an algebraic recursion amongst some finite number of consecutive elements in a set of expectation values of an appropriately chosen basis set over the natural number powers of the position operator as long as the function under consideration and the system Hamiltonian are both autonomous. This recursion corresponds to a denumerable infinite number of algebraic equations whose solutions can or can not be obtained analytically. This idea is not completely original. There are many recursive relations amongst the expectation values of the natural number powers of position operator. However, those recursions may not be always efficient to get the system energy values and especially the eigenstate wavefunctions. The present approach is somehow improved and generalized form of those expansions. We focus on this issue for a specific system where the Hamiltonian is defined on the coordinate of a curved space instead of the Cartesian one.

  19. Magnetic-dipole-to-electric-quadrupole cross-susceptibilities for relativistic hydrogenlike atoms in some low-lying discrete energy eigenstates

    NASA Astrophysics Data System (ADS)

    Stefańska, Patrycja

    2017-01-01

    In this paper we present tabulated data for magnetic-dipole-to-electric-quadrupole cross-susceptibilities (χ M 1 →E 2) for Dirac one-electron atoms with a pointlike, spinless and motionless nucleus of charge Ze. Numerical values of this susceptibility for the hydrogen atom (Z = 1) and for hydrogenic ions with 2 ⩽ Z ⩽ 137 are computed from the general analytical formula, recently derived by us (Stefanska, 2016), valid for an arbitrary discrete energy eigenstate. In this work we provide 30 tables with the values of χ M 1 →E 2 for the ground state, and also for the first, the second and the third set of excited states (i.e.: 2s1/2, 2p1/2, 2p3/2, 3s1/2, 3p1/2, 3p3/2, 3d3/2, 3d5/2, 4s1/2, 4p1/2, 4p3/2, 4d3/2, 4d5/2, 4f5/2 and 4f7/2) of the relativistic hydrogenlike atoms. The value of the inverse of the fine-structure constant used in the calculations is α-1 = 137.035999139, and was taken from CODATA 2014.

  20. Impact of the Condensed-Phase Environment on the Translation-Rotation Eigenstates and Spectra of a Hydrogen Molecule in Clathrate Hydrates.

    PubMed

    Powers, Anna; Marsalek, Ondrej; Xu, Minzhong; Ulivi, Lorenzo; Colognesi, Daniele; Tuckerman, Mark E; Bačić, Zlatko

    2016-01-21

    We systematically investigate the manifestations of the condensed-phase environment of the structure II clathrate hydrate in the translation-rotation (TR) dynamics and the inelastic neutron scattering (INS) spectra of an H2 molecule confined in the small dodecahedral cage of the hydrate. The aim is to elucidate the extent to which these properties are affected by the clathrate water molecules beyond the confining cage and the proton disorder of the water framework. For this purpose, quantum calculations of the TR eigenstates and INS spectra are performed for H2 inside spherical clathrate domains of gradually increasing radius and the number of water molecules ranging from 20 for the isolated small cage to more than 1800. For each domain size, several hundred distinct hydrogen-bonding topologies are constructed in order to simulate the effects of the proton disorder. Our study reveals that the clathrate-induced splittings of the j = 1 rotational level and the translational fundamental of the guest H2 are influenced by the condensed-phase environment to a dramatically different degree, the former very strongly and the latter only weakly.

  1. Zero-mass limit of a Dirac spinor with general spin orientation

    NASA Astrophysics Data System (ADS)

    Şahin, İ.

    2016-11-01

    The helicity eigenstates that describe fermions with a special spin orientation (parallel or antiparallel to the direction of momentum) provide a considerable simplification in calculations. Hence, it is generally preferred to use the helicity basis during calculations in relativistic quantum mechanics or the quantum field theory. Possibly for the above reason, Dirac spinors describing a general spin orientation have been ignored in many textbooks. Although the helicity eigenstates give an almost complete understanding of the behavior of the free Dirac solutions, the zero-mass limit is one of its exceptions. The zero-mass behavior of the free spinor with general spin orientation and its relation with chirality eigenstates has been skipped in textbooks and hence it deserves a clear, detailed investigation. In this paper we obtain the free Dirac spinors describing a general spin orientation and examine their zero-mass limit. We also briefly discuss some of the implications of this small-mass behavior of the spinors on particle physics.

  2. Purity assessment of condensed tannin fractions by nuclear magnetic resonance (NMR) spectroscopy

    USDA-ARS?s Scientific Manuscript database

    Unambiguous investigation of condensed tannin (CT) structure-activity relationships in biological systems requires the use of highly enriched CT fractions of defined chemical purity. Purification of CTs from Sorghum bicolor, Trifolium repens, Theobroma cacao, Lespedeza cuneata, Lotus pedunculatus, a...

  3. Stress and phase purity analyses of diamond films deposited through laser-assisted combustion synthesis.

    PubMed

    Guillemet, T; Xie, Z Q; Zhou, Y S; Park, J B; Veillere, A; Xiong, W; Heintz, J M; Silvain, J F; Chandra, N; Lu, Y F

    2011-10-01

    Diamond films were deposited on silicon and tungsten carbide substrates in open air through laser-assisted combustion synthesis. Laser-induced resonant excitation of ethylene molecules was achieved in the combustion process to promote diamond growth rate. In addition to microstructure study by scanning electron microscopy, Raman spectroscopy was used to analyze the phase purity and residual stress of the diamond films. High-purity diamond films were obtained through laser-assisted combustion synthesis. The levels of residual stress were in agreement with corresponding thermal expansion coefficients of diamond, silicon, and tungsten carbide. Diamond-film purity increases while residual stress decreases with an increasing film thickness. Diamond films deposited on silicon substrates exhibit higher purity and lower residual stress than those deposited on tungsten carbide substrates. © 2011 American Chemical Society

  4. Effects of TiCl4 Purity on the Sinterability of Armstrong-Processed Ti Powder

    SciTech Connect

    Weil, K. Scott; Hovanski, Yuri; Lavender, Curt A.

    2009-04-03

    A series of high purity and low purity powders were synthesized from TiCl4 by the Armstrong process. While both powders displayed swelling when consolidated and sintered, the lower purity powder exhibited this phenomenon in significantly lower degree. The improvement is attributed to the increase in the onset of sintering temperature, which mitigates the entrapment of volatile impurities that would otherwise lead to pore formation and growth. The net effect is that the use of a lower purity TiCl4 may beneficial in two ways: (1) it is a potentially lower cost precursor to Ti powder production and (2) the trace impurities allow higher density components to be fabricated via a typical low-cost press and sinter approach.

  5. Superconducting radio-frequency cavities made from medium and low-purity niobium ingots

    NASA Astrophysics Data System (ADS)

    Ciovati, Gianluigi; Dhakal, Pashupati; Myneni, Ganapati R.

    2016-06-01

    Superconducting radio-frequency cavities made of ingot niobium with residual resistivity ratio (RRR) greater than 250 have proven to have similar or better performance than fine-grain Nb cavities of the same purity, after standard processing. The high purity requirement contributes to the high cost of the material. As superconducting accelerators operating in continuous-wave typically require cavities to operate at moderate accelerating gradients, using lower purity material could be advantageous not only to reduce cost but also to achieve higher Q 0-values. In this contribution we present the results from cryogenic RF tests of 1.3-1.5 GHz single-cell cavities made of ingot Nb of medium (RRR = 100-150) and low (RRR = 60) purity from different suppliers. Cavities made of medium-purity ingots routinely achieved peak surface magnetic field values greater than 70 mT with an average Q 0-value of 2 × 1010 at 2 K after standard processing treatments. The performances of cavities made of low-purity ingots were affected by significant pitting of the surface after chemical etching.

  6. Adherence of Staphylococcus aureus to Dyneema Purity® Patches and to Clinically Used Cardiovascular Prostheses

    PubMed Central

    Basir, Amir; Gründeman, Paul; Moll, Frans; van Herwaarden, Joost; Pasterkamp, Gerard

    2016-01-01

    Various materials that are used for vascular and heart valve prostheses carry drawbacks: some require anticoagulant drugs or have moderate durability; others are not suitable for endovascular treatment. These prostheses are associated with bacterial infections. A material potentially suitable for prostheses is Dyneema Purity®, made of ultra—high-molecular-weight polyethylene. Dyneema Purity® fibers are very thin, flexible, resistant to fatigue and abrasion, and have high strength. S. aureus adherence to Dyneema Purity® was tested and compared with currently used cardiovascular prostheses. We compared adhesion of S. aureus to Dyneema Purity® (1 membrane-based and 1 yarn-composed patch) with 5 clinically used yarn-composed polyester and membrane-based expanded polytetrafluoroethylene patches. Patches were contaminated with S. aureus bacteria and bacterial adherence was quantified. S. aureus adherence was also visualized in flow conditions. Overall, bacterial adherence was higher on yarn-composed prosthesis materials, with a rough surface, than on the membrane-based materials, with a smooth surface. Adherence to Dyneema Purity® materials was non-inferior to the currently used materials. Therefore, patches of Dyneema Purity® might be attractive for use in cardiovascular applications such as catheter-based heart valves and endovascular prostheses by their good mechanical properties combined with their noninferiority regarding bacterial adhesion. PMID:27583703

  7. Superconducting radio-frequency cavities made from medium and low-purity niobium ingots

    SciTech Connect

    Ciovati, Gianluigi; Dhakal, Pashupati; Myneni, Ganapati R.

    2016-04-07

    Superconducting radio-frequency cavities made of ingot niobium with residual resistivity ratio (RRR) greater than 250 have proven to have similar or better performance than fine-grain Nb cavities of the same purity, after standard processing. The high purity requirement contributes to the high cost of the material. As superconducting accelerators operating in continuous-wave typically require cavities to operate at moderate accelerating gradients, using lower purity material could be advantageous not only to reduce cost but also to achieve higher Q0-values. In this contribution we present the results from cryogenic RF tests of 1.3–1.5 GHz single-cell cavities made of ingot Nb of medium (RRR = 100–150) and low (RRR = 60) purity from different suppliers. Cavities made of medium-purity ingots routinely achieved peak surface magnetic field values greater than 70 mT with an average Q0-value of 2 × 1010 at 2 K after standard processing treatments. As a result, the performances of cavities made of low-purity ingots were affected by significant pitting of the surface after chemical etching.

  8. Superconducting radio-frequency cavities made from medium and low-purity niobium ingots

    DOE PAGES

    Ciovati, Gianluigi; Dhakal, Pashupati; Myneni, Ganapati R.

    2016-04-07

    Superconducting radio-frequency cavities made of ingot niobium with residual resistivity ratio (RRR) greater than 250 have proven to have similar or better performance than fine-grain Nb cavities of the same purity, after standard processing. The high purity requirement contributes to the high cost of the material. As superconducting accelerators operating in continuous-wave typically require cavities to operate at moderate accelerating gradients, using lower purity material could be advantageous not only to reduce cost but also to achieve higher Q0-values. In this contribution we present the results from cryogenic RF tests of 1.3–1.5 GHz single-cell cavities made of ingot Nb ofmore » medium (RRR = 100–150) and low (RRR = 60) purity from different suppliers. Cavities made of medium-purity ingots routinely achieved peak surface magnetic field values greater than 70 mT with an average Q0-value of 2 × 1010 at 2 K after standard processing treatments. As a result, the performances of cavities made of low-purity ingots were affected by significant pitting of the surface after chemical etching.« less

  9. Flocculation of high purity wheat straw soda lignin.

    PubMed

    Piazza, G J; Lora, J H; Garcia, R A

    2014-01-01

    In industrial process, acidification causes non-sulfonated lignin insolubility. The flocculants poly(diallyldimethylammonium chloride) (pDADMAC) and bovine blood (BB) also caused lignin insolubility while cationic polyacrylamide, chitosan, and soy protein PF 974 were ineffective. Turbidity determined optimal flocculant, but turbidity magnitude with BB was greater than expected. pDADMAC caused negative lignin Zeta potential to became positive, but BB-lignin Zeta potential was always negative. Insoluble lignin did not gravity sediment, and flocculant-lignin mixtures were centrifuged. Pellet and supernatant dry mass and corrected spectroscopic results were in good agreement for optimal pDADMAC and BB. Spectroscopy showed 87-92% loss of supernatant lignin. Nitrogen analysis showed BB concentrated in the pellet until the pellet became saturated with BB. Subtracting ash and BB mass from pellet and supernatant mass confirmed optimal BB. Low levels of alum caused increased lignin flocculation at lower levels of pDADMAC and BB, but alum did not affect optimal flocculant. Published by Elsevier Ltd.

  10. Performance of A Compact Multi-crystal High-purity Germanium Detector Array for Measuring Coincident Gamma-ray Emissions

    SciTech Connect

    Howard, Chris; Daigle, Stephen; Buckner, Matt; Erikson, Luke E.; Runkle, Robert C.; Stave, Sean C.; Champagne, Art; Cooper, Andrew; Downen, Lori; Glasgow, Brian D.; Kelly, Keegan; Sallaska, Anne

    2015-02-18

    The Multi-sensor Airborne Radiation Survey (MARS) detector is a 14-crystal array of high-purity germanium (HPGe) detectors housed in a single cryostat. The array was used to measure the astrophysical S-factor for the 14N(p,γ)15O* reaction for several transition energies at an effective center of mass energy of 163 keV. Owing to the segmented nature of the MARS detector, the effect of gamma-ray summing was greatly reduced in comparison to past experiments which utilized large, single-crystal detectors. The new S-factor values agree within the uncertainties with the past measurements. Details of the analysis and detector performance will be presented.

  11. Carbon ejection from a SiO2/SiC(0001) interface by annealing in high-purity Ar

    NASA Astrophysics Data System (ADS)

    Kobayashi, Takuma; Kimoto, Tsunenobu

    2017-08-01

    We found that carbon-associated byproducts formed at the dry-oxidized SiO2/SiC(0001) interface could be decomposed and emitted on the SiO2 side by high-purity Ar annealing. We measured the concentration of ejected carbon atoms in SiO2 by secondary ion mass spectrometry, and found that it strongly depended on the condition of oxide formation (dry-oxidation, nitridation treatment, and phosphorus treatment). This work provides indirect but unambiguous evidence for the formation of carbon byproducts at the SiO2/SiC interface, and indicates that phosphorus treatment removes these byproducts, leading to a significant reduction in interface defects.

  12. The D{sup 0}-{bar D}{sup 0} Mass Difference from a Dispersion Relation

    SciTech Connect

    Falk, A

    2004-02-19

    We study the Standard Model prediction for the mass difference between the two neutral meson mass eigenstates, {Delta}. We derive a dispersion relation based on heavy quark effective theory that relates {Delta} to an integral of the width difference of heavy mesons, {Delta}{Lambda}, over varying values of the heavy meson mass. Modeling the {sub D}-dependence of certain decay partial widths, we investigate the effects of SU(3) breaking from phase space on the mass difference. We find that {Delta} may be comparable in magnitude to {Delta}{Lambda} in the Standard Model.

  13. CCQM-K104 key comparison (avermectin B1a) on the characterization of organic substances for chemical purity

    NASA Astrophysics Data System (ADS)

    Dai, Xinhua; Zhang, Wei; Li, Hongmei; Huang, Ting; Li, Mengwan; Quan, Can; Zhang, Qinghe; Davies, Stephen R.; Warren, John; Lo, Man-fung; Kakoulides, Elias; Ceyhan Gören, Ahmet; Marbumrung, Sornkrit; Pfeifer, Dietmar; Ün, İlker; Gündüz, Simay; Yilmaz, Hasibe; Kankaew, Pornhatai; Sudsiri, Nittaya; Shearman, Kittiya; Pookrod, Preeyaporn; Polzer, Joachim; Radeck, Wolfgang

    2017-01-01

    Under the Comité Consultatif pour la Quantité de Matière (CCQM), a key comparison, CCQM-K104, was coordinated by the National Institute of Metrology (NIM). The comparison was designed to demonstrate a laboratory's performance in determining the mass fraction of the main component in a complex high purity organic material. Nine NMIs or DIs participated in the comparison. Eight participants reported their results. An additional impurity was resolved from the avermectin B1a peak and was tentatively identified as an unknown impurity by NMIA (National Measurement Institute (Australia)). It was subsequently identified by NIM as a diastereoisomer of avermectin B1a at the C-26 position. Final reference value (KCRV) = 924.63 mg/g, with uncertainty (k=1) = 3.89 mg/g, and expanded uncertainty = 8.97 mg/g. The degrees of equivalence with the avermectin B1a KCRV for each participant were reported. The measurement results and degrees of equivalence should be indicative of the performance of a laboratory's measurement capability for the purity assignment of organic compounds of high structural complexity (relative molecular mass range of 500 Da -1000 Da and low polarity (-log KOW <= -2). Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  14. Inelastic neutron scattering spectra of a hydrogen molecule in a nanocavity: Methodology for quantum calculations incorporating the coupled five-dimensional translation-rotation eigenstates

    NASA Astrophysics Data System (ADS)

    Xu, Minzhong; Bačić, Zlatko

    2011-11-01

    We present an in-depth description of the methodology for accurate quantum calculation of the inelastic neutron scattering (INS) spectra of an H2 molecule confined inside a nanosize cavity of an arbitrary shape. This methodology was introduced in a recent work [M. Xu, L. Ulivi, M. Celli, D. Colognesi, and Z. Bačić, Phys. Rev. BPRBMDO1098-012110.1103/PhysRevB.83.241403 83, 241403(R) (2011)], where the INS spectra of para- and ortho-H2 in the small cage of the structure II clathrate hydrate were simulated and compared with the measured spectra. The key distinctive feature of our approach, and its main strength and advantage, is the use of the coupled quantum 5D translation-rotation (TR) energy levels and wave functions of the entrapped H2 molecule, rigorously calculated on the 5D intermolecular potential energy surface (PES), as the initial and the final states of the INS transitions. In this work, we describe the implementation of the 5D TR wave functions within the quantum INS formalism, and obtain the working expressions for the matrix elements required to compute the INS spectra of the nanoconfined H2 molecule. The computational approach devised for efficient calculation of the 5D TR eigenstates in the compact contracted basis, indispensable for our quantum simulation of the INS spectra, is presented as well. Since the TR coupling is fully taken into account, the computed INS spectra exhibit a uniquely high degree of realism and faithfully reflect the quantum dynamics of H2 on the PES of the host environment.

  15. Stubborn contaminants: influence of detergents on the purity of the multidrug ABC transporter BmrA.

    PubMed

    Wiseman, Benjamin; Kilburg, Arnaud; Chaptal, Vincent; Reyes-Mejia, Gina Catalina; Sarwan, Jonathan; Falson, Pierre; Jault, Jean-Michel

    2014-01-01

    Despite the growing interest in membrane proteins, their crystallization remains a major challenge. In the course of a crystallographic study on the multidrug ATP-binding cassette transporter BmrA, mass spectral analyses on samples purified with six selected detergents revealed unexpected protein contamination visible for the most part on overloaded SDS-PAGE. A major contamination from the outer membrane protein OmpF was detected in purifications with Foscholine 12 (FC12) but not with Lauryldimethylamine-N-oxide (LDAO) or any of the maltose-based detergents. Consequently, in the FC12 purified BmrA, OmpF easily crystallized over BmrA in a new space group, and whose structure is reported here. We therefore devised an optimized protocol to eliminate OmpF during the FC12 purification of BmrA. On the other hand, an additional band visible at ∼110 kDa was detected in all samples purified with the maltose-based detergents. It contained AcrB that crystallized over BmrA despite its trace amounts. Highly pure BmrA preparations could be obtained using either a ΔacrAB E. coli strain and n-dodecyl-β-D-maltopyranoside, or a classical E. coli strain and lauryl maltose neopentyl glycol for the overexpression and purification, respectively. Overall our results urge to incorporate a proteomics-based purity analysis into quality control checks prior to commencing crystallization assays of membrane proteins that are notoriously arduous to crystallize. Moreover, the strategies developed here to selectively eliminate obstinate contaminants should be applicable to the purification of other membrane proteins overexpressed in E. coli.

  16. Stubborn Contaminants: Influence of Detergents on the Purity of the Multidrug ABC Transporter BmrA

    PubMed Central

    Chaptal, Vincent; Reyes-Mejia, Gina Catalina; Sarwan, Jonathan; Falson, Pierre; Jault, Jean-Michel

    2014-01-01

    Despite the growing interest in membrane proteins, their crystallization remains a major challenge. In the course of a crystallographic study on the multidrug ATP-binding cassette transporter BmrA, mass spectral analyses on samples purified with six selected detergents revealed unexpected protein contamination visible for the most part on overloaded SDS-PAGE. A major contamination from the outer membrane protein OmpF was detected in purifications with Foscholine 12 (FC12) but not with Lauryldimethylamine-N-oxide (LDAO) or any of the maltose-based detergents. Consequently, in the FC12 purified BmrA, OmpF easily crystallized over BmrA in a new space group, and whose structure is reported here. We therefore devised an optimized protocol to eliminate OmpF during the FC12 purification of BmrA. On the other hand, an additional band visible at ∼110 kDa was detected in all samples purified with the maltose-based detergents. It contained AcrB that crystallized over BmrA despite its trace amounts. Highly pure BmrA preparations could be obtained using either a ΔacrAB E. coli strain and n-dodecyl-β-D-maltopyranoside, or a classical E. coli strain and lauryl maltose neopentyl glycol for the overexpression and purification, respectively. Overall our results urge to incorporate a proteomics-based purity analysis into quality control checks prior to commencing crystallization assays of membrane proteins that are notoriously arduous to crystallize. Moreover, the strategies developed here to selectively eliminate obstinate contaminants should be applicable to the purification of other membrane proteins overexpressed in E. coli. PMID:25517996

  17. Evaluation of Prebiotic Effects of High-Purity Galactooligosaccharides in vitro and in vivo

    PubMed Central

    Hong, Ki Bae; Kim, Jae Hwan; Kwon, Hyuk Kon; Han, Sung Hee

    2016-01-01

    Summary Galactooligosaccharides (GOS) are an important class of dietary prebiotics that exert beneficial effects on intestinal microbiota and gut barrier function. In this study, high-purity GOS (HP-GOS) were investigated in vitro and in vivo and confirmed as prebiotic ingredients in rat diet. HP-GOS were successfully produced using a two-step process, enzymatic hydrolysis and fermentation by yeast. They were found to serve as a good substrate and carbon source for supporting the growth of probiotic bacteria more effectively than other commercial GOS. Following administration of 1% (by mass) of HP-GOS to rats, the growth of Bifidobacterium bifidum and B. longum in the gut increased most rapidly up to 12 h, and thereafter the increase was slow. Therefore, 1% HP-GOS was found to be acceptable for the growth of probiotic bacteria. Groups of animals that were orally administered HP-GOS and bifidobacteria during the study, and the group administered HP-GOS during the 2nd (days 13–15) and 4th (days 28–30) period of the study had significantly (p<0.05) higher numbers of bifidobacteria in faeces than groups receiving a single dose of bifidobacteria. HP-GOS affected the expression of genes encoding glucagon-like peptide-1 (GLP-1) and peptide YY (PYY). There was a significant upregulation of GLP-1 and PYY mRNA with HP-GOS and bifidobacteria intake. We propose that the prebiotic properties of HP-GOS are potentially valuable for the production of functional foods for human consumption. PMID:27904405

  18. Parallel SFC/MS-MUX screening to assess enantiomeric purity.

    PubMed

    Laskar, Derek B; Zeng, Lu; Xu, Rongda; Kassel, Daniel B

    2008-08-01

    Enantiomeric excess (ee) was evaluated for two internally synthesized compound libraries using a high-throughput automated, intelligent four-channel parallel supercritical fluid chromatography/mass spectrometry system equipped with a multiplexed ion source interface (SFC/MS-MUX). The two libraries contained compounds spanning a wide range of enantiomeric ratios with structurally diverse chemical scaffolds and stereogenic centers. The system analyzed each sample simultaneously against four chiral columns using up to six organic modifiers. Enhancements to our previously published parallel supercritical fluid chromatography/mass spectrometry system were implemented to address the challenges associated with automated trace enantiomer identification and quantitation. A reversal of enantiomer elution order was observed for several samples across multiple CSPs and modifiers. The relationship between elution order and % ee accuracy is presented for compounds exhibiting high, middle and low % ee values. Despite incidences in which the minor enantiomer eluted prior to the major enantiomer with less than baseline resolution, the overall % ee was in agreement with separations in which full baseline resolution was achieved. The methods presented here demonstrate the value and utility of high-throughput ee determinations to support drug discovery and development programs.

  19. Connecting Fermion Masses and Mixings to BSM Physics - Leptons

    NASA Astrophysics Data System (ADS)

    Stephenson, Gerard J., Jr.; Goldman, Terrence

    2015-10-01

    The universality of the Weak Interaction suggests that the structure of the Dirac mass matrix for neutrinos should be the same as that for the charged fermions. Thus, it must be true that there are at least three Majorana fermions, not necessarily mass eigenstates, which are sterile under the weak and electromagnetic interactions, and that three of these couple to the Higgs. We show that specific models of the sterile Majorana mass matrix exist for which the resulting effective active neutrino Majorana mass matrix is nearly diagonal in the current basis, with small but finite masses. Combined with the structure of the mass matrix for the charged leptons, this leads to a PMNS matrix for the lepton mixing that is nearly, but not exactly, tri-bi-maximal. Alt email:gjs@phys.unm.edu

  20. NMR-based approach to the analysis of radiopharmaceuticals: radiochemical purity, specific activity, and radioactive concentration values by proton and tritium NMR spectroscopy.

    PubMed

    Schenk, David J; Dormer, Peter G; Hesk, David; Pollack, Scott R; Lavey, Carolee Flader

    2015-06-15

    Compounds containing tritium are widely used across the drug discovery and development landscape. These materials are widely utilized because they can be efficiently synthesized and produced at high specific activity. Results from internally calibrated (3)H and (1)H nuclear magnetic resonance (NMR) spectroscopy suggests that at least in some cases, this calibrated approach could supplement or potentially replace radio-high-performance liquid chromatography for radiochemical purity, dilution and scintillation counting for the measurement of radioactivity per volume, and liquid chromatography/mass spectrometry analysis for the determination of specific activity. In summary, the NMR-derived values agreed with those from the standard approaches to within 1% to 9% for solution count and specific activity. Additionally, the NMR-derived values for radiochemical purity deviated by less than 5%. A benefit of this method is that these values may be calculated at the same time that (3)H NMR analysis provides the location and distribution of tritium atoms within the molecule. Presented and discussed here is the application of this method, advantages and disadvantages of the approach, and a rationale for utilizing internally calibrated (1)H and (3)H NMR spectroscopy for specific activity, radioactive concentration, and radiochemical purity whenever acquiring (3)H NMR for tritium location.

  1. Deterministic chaos in entangled eigenstates

    NASA Astrophysics Data System (ADS)

    Schlegel, K. G.; Förster, S.

    2008-05-01

    We investigate the problem of deterministic chaos in connection with entangled states using the Bohmian formulation of quantum mechanics. We show for a two particle system in a harmonic oscillator potential, that in a case of entanglement and three energy eigen-values the maximum Lyapunov-parameters of a representative ensemble of trajectories for large times develops to a narrow positive distribution, which indicates nearly complete chaotic dynamics. We also present in short results from two time-dependent systems, the anisotropic and the Rabi oscillator.

  2. The effect of initial purity on the stability of solutions in storage.

    PubMed

    Popa-Burke, Ioana; Novick, Steven; Lane, Charles A; Hogan, Robin; Torres-Saavedra, Pedro; Hardy, Brian; Ray, Brenda; Lindsay, Melissa; Paulus, Iris; Miller, Luke

    2014-02-01

    Many modern compound-screening technologies are highly miniaturized, resulting in longer-lasting solution stocks in compound management laboratories. As the ages of some stocks stretch into years, it becomes increasingly important to ensure that the DMSO solutions remain of high quality. It can be a burden to check the quality of a large library of compound solutions continuously, and so a study was devised to link the effects of initial compound purity and physicochemical properties of the compounds with the current purity of DMSO solutions. Approximately 5000 compounds with initial purity of at least 80% were examined. Storage conditions were held or observed to be relatively constant and so were eliminated as potential predictors. This allowed the evaluation of the effects of other factors on the stability of solutions, such as initial purity, number of freeze-thaw cycles, age of the solution, and multiple calculated physicochemical parameters. Of all the factors investigated, initial purity was the only one that had a clear effect on stability. None of the other parameters investigated (physicochemical properties, number of freeze-thaw cycles, age of solutions) had a statistically significant effect on stability.

  3. Nanopurification of silicon from 84% to 99.999% purity with a simple and scalable process

    PubMed Central

    Zong, Linqi; Zhu, Bin; Lu, Zhenda; Tan, Yingling; Jin, Yan; Liu, Nian; Hu, Yue; Gu, Shuai; Zhu, Jia; Cui, Yi

    2015-01-01

    Silicon, with its great abundance and mature infrastructure, is a foundational material for a range of applications, such as electronics, sensors, solar cells, batteries, and thermoelectrics. These applications rely on the purification of Si to different levels. Recently, it has been shown that nanosized silicon can offer additional advantages, such as enhanced mechanical properties, significant absorption enhancement, and reduced thermal conductivity. However, current processes to produce and purify Si are complex, expensive, and energy-intensive. Here, we show a nanopurification process, which involves only simple and scalable ball milling and acid etching, to increase Si purity drastically [up to 99.999% (wt %)] directly from low-grade and low-cost ferrosilicon [84% (wt %) Si; ∼$1/kg]. It is found that the impurity-rich regions are mechanically weak as breaking points during ball milling and thus, exposed on the surface, and they can be conveniently and effectively removed by chemical etching. We discovered that the purity goes up with the size of Si particles going down, resulting in high purity at the sub–100-nm scale. The produced Si nanoparticles with high purity and small size exhibit high performance as Li ion battery anodes, with high reversible capacity (1,755 mAh g−1) and long cycle life (73% capacity retention over 500 cycles). This nanopurification process provides a complimentary route to produce Si, with finely controlled size and purity, in a diverse set of applications. PMID:26483490

  4. Nanopurification of silicon from 84% to 99.999% purity with a simple and scalable process.

    PubMed

    Zong, Linqi; Zhu, Bin; Lu, Zhenda; Tan, Yingling; Jin, Yan; Liu, Nian; Hu, Yue; Gu, Shuai; Zhu, Jia; Cui, Yi

    2015-11-03

    Silicon, with its great abundance and mature infrastructure, is a foundational material for a range of applications, such as electronics, sensors, solar cells, batteries, and thermoelectrics. These applications rely on the purification of Si to different levels. Recently, it has been shown that nanosized silicon can offer additional advantages, such as enhanced mechanical properties, significant absorption enhancement, and reduced thermal conductivity. However, current processes to produce and purify Si are complex, expensive, and energy-intensive. Here, we show a nanopurification process, which involves only simple and scalable ball milling and acid etching, to increase Si purity drastically [up to 99.999% (wt %)] directly from low-grade and low-cost ferrosilicon [84% (wt %) Si; ∼$1/kg]. It is found that the impurity-rich regions are mechanically weak as breaking points during ball milling and thus, exposed on the surface, and they can be conveniently and effectively removed by chemical etching. We discovered that the purity goes up with the size of Si particles going down, resulting in high purity at the sub-100-nm scale. The produced Si nanoparticles with high purity and small size exhibit high performance as Li ion battery anodes, with high reversible capacity (1,755 mAh g(-1)) and long cycle life (73% capacity retention over 500 cycles). This nanopurification process provides a complimentary route to produce Si, with finely controlled size and purity, in a diverse set of applications.

  5. Optimisation of integrated biodiesel production. Part I. A study of the biodiesel purity and yield.

    PubMed

    Vicente, Gemma; Martínez, Mercedes; Aracil, José

    2007-07-01

    This study consists of the development and optimisation of the potassium hydroxide-catalysed synthesis of fatty acid methyl esters (biodiesel) from sunflower oil. A factorial design of experiments and a central composite design have been used. The variables chosen were temperature, initial catalyst concentration by weight of sunflower oil and the methanol:vegetable oil molar ratio, while the responses were biodiesel purity and yield. The initial catalyst concentration is the most important factor, having a positive influence on biodiesel purity, but a negative one on biodiesel yield. Temperature has a significant positive effect on biodiesel purity and a significant negative influence on biodiesel yield. The methanol:vegetable oil molar ratio is only significant for the biodiesel purity, having a positive influence. Second-order models were obtained to predict biodiesel purity and yield as a function of these variables. The best conditions are 25 degrees C, a 1.3%wt for the catalyst concentration and a 6:1 methanol:sunflower oil molar ratio.

  6. The Next Generation Safeguards Initiative s High-Purity Uranium-233 Preservation Effort

    SciTech Connect

    Krichinsky, Alan M; Bostick, Debra A; Giaquinto, Joseph; Bayne, Charles; Goldberg, Dr. Steven A.; Humphrey, Dr. Marc; Hutcheon, Dr. Ian D.; Sobolev, Taissa

    2012-01-01

    High-purity 233U serves as a crucial reference material for accurately quantifying and characterizing uranium. The most accurate analytical results which can be obtained only with high-purity 233U certified reference material (CRM) are required when used to confirm compliance with international safeguards obligations and international nonproliferation agreements. The U.S. supply of 233U CRM is almost depleted, and existing domestic stocks of this synthetic isotope are scheduled to be down-blended for disposition with depleted uranium beginning in 2015. Down blending batches of high-purity 233U will permanently eliminate the value of this material as a CRM. Furthermore, no replacement 233U stocks are expected to be produced in the future due to a lack of operating production capability and the high cost of replacing such capability. Therefore, preserving select batches of high-purity 233U is of great value and will assist in retaining current analytical capabilities for uranium-bearing samples. Any organization placing a priority on accurate results of uranium analyses, or on the confirmation of trace uranium in environmental samples, has a vested interest in preserving this material. This paper describes the need for high-purity 233U, the consequences organizations and agencies face if this material is not preserved, and the progress and future plans for preserving select batches of the purest 233U materials from disposition. This work is supported by the Next Generation Safeguards Initiative, Office of Nonproliferation and International Security, National Nuclear Security Administration.

  7. Development and validation of a reversed-phase high-performance liquid chromatography method for routine identification and purity assessment of high-purity steviol glycoside sweeteners.

    PubMed

    Bililign, Tsion; Moore, Jeffrey C; Tan, Shane; Leeks, Allan T

    2014-02-12

    The widespread application of stevia-based sweeteners in food products has resulted in the need for reliable analytical methods for measuring the purity and identity of high-purity steviol glycoside ingredients. The objective of this research was to develop and validate a new reversed-phase separation method capable of separating and quantifying nine steviol glycosides present in typical high-purity stevia extract ingredients. Results of the study established the linearity of the method at a correlation factor of 1.000 for the two major components and other minor components of this food ingredient. Method accuracy values were in the range of 99.1-100.9%. The percent relative standard deviation for six independent assay determinations was 1.0%. The method was determined to be robust for minor changes in column temperature, initial acetonitrile content, flow rate, and wavelength. The validated high-performance liquid chromatography method was found to be suitable to be included by USP as a Food Chemicals Codex compendial standard for steviol glycosides.

  8. [Simultaneously preparation of grams of high purity tyrosol, crenulatin and salidroside from Rhodiola crenulata].

    PubMed

    Luo, Xin; Wang, Xue-jing; Li, Shi-ping; Zhang, Qiao; Zhao, Yi-wu; Huang Wen-zhe; Wang, Zhen-zhong; Xiao, Wei

    2015-04-01

    Tyrosol, crenulatin and salidroside are the main active constituents of Rhodiola crenulata, with extensive pharmacological activities. In the study, grams of high purity tyrosol, crenulatin and salidroside were simultaneously separated from R. crenulata by the first time. Firstly, R. crenulata was extracted by 70% alcohol. Then, with the yields of three compounds as the index, the macroporous resin was optimized. At last, grams of high purity tyrosol, crenulatin and salidroside were isolated by D-101 macroporousresin, purified by column chromatography. Detected by HPLC, the purity of three compounds were higher than 98%. This method has the advantages of simple process and operation, less dosage of organic solvent, highly yield and reproducibility, suitable for the simultaneously preparation of tyrosol, crenulatin and salidroside.

  9. Physically Realizable Space for the Purity-Depolarization Plane for Polarized Light Scattering Media

    NASA Astrophysics Data System (ADS)

    Tariq, Aziz; Li, Pengcheng; Chen, Dongsheng; Lv, Donghong; Ma, Hui

    2017-07-01

    We propose a physically realizable space for the polarized light scattering measurement using the Stokes-Mueller formalism by a purity-index-depolarization-index (PI -PΔ ) plane. The parameter PI is defined from indices of polarimetric purity (IPP), which exhibits the overall magnitude of the polarimetric randomness of a medium, while the depolarization index (PΔ ) delineates a proper global degree of polarimetric purity and may also refer to the average measure of depolarization power of the scattering medium. Subregions and curves connecting the edge points in the plane are obtained by imposing certain constraints on the IPP; consequently any point on the subregion indicates the information related to a decomposition of the Mueller matrix into its components as a convex sum. From the same set of constraints, complete information about the depolarization index versus the entropy [S (M ) -PΔ ] diagram is recovered. This work provides a simple geometric representation and a deeper perceptivity of the light scattering media comprising depolarization.

  10. Purity of (28)Si-Enriched Silicon Material Used for the Determination of the Avogadro Constant.

    PubMed

    D'Agostino, Giancarlo; Di Luzio, Marco; Mana, Giovanni; Oddone, Massimo; Bennett, John W; Stopic, Attila

    2016-07-05

    At present, counting atoms in a one-kilogram sphere made of (28)Si-enriched silicon allows the determination of the Avogadro constant with the 2.0 × 10(-8) relative standard uncertainty required for the realization of the definition of the new kilogram. With the exception of carbon, oxygen, boron, nitrogen, and hydrogen, the claimed uncertainty is based on the postulation that the silicon material used to manufacture the sphere was above a particular level of purity. Two samples of the silicon were measured using instrumental neutron activation analysis to collect experimental data to test the purity assumption. The results obtained in two experiments carried out using different research reactor neutron sources are reported. The analysis confirmed that the silicon material was of sufficient purity by quantifying the ultratrace concentration of 12 elements and determining the detection limits of another 54 elements.

  11. Microstructure Evolution in High Purity Aluminum Single Crystal Processed by Equal Channel Angular Pressing (ECAP).

    PubMed

    Dong, Jinfang; Dong, Qing; Dai, Yongbing; Xing, Hui; Han, Yanfeng; Ma, Jianbo; Zhang, Jiao; Wang, Jun; Sun, Baode

    2017-01-22

    Aluminum single crystal with 99.999% purity was deformed at room temperature by equal channel angular pressing (ECAP) up to 16 passes. Grain size and misorientation of processed samples were quantitatively characterized by TEM and EBSD. The results show that the refinement efficiency of high purity aluminum single crystal was poor in the initial stage. Extrusion by fewer ECAP passes (n ≤ 8) resulted in only elongated grains containing a large number of subgrains and small misorientations between grains. Stable microstructures of nearly equiaxed grains with high misorientations were obtained by 15 passages, indicating that the initial extremely coarse grains and highly uniform grain orientation are not conducive to the accumulation of strain energy. The initial state of high purity aluminum has a significant effect on the refining efficiency of the ECAP process.

  12. [Determination of trace sodium ion in high purity water by graphite furnace atomic absorption spectrometry].

    PubMed

    Yuan, Xia; Shen, Shi-gang; Sun, Han-wen

    2007-01-01

    The present paper studied on the determination of trace Na+ in high purity water by graphite furnace atom absorption spectrometry. A method of directly on-line concentrating samples in graphite furnace, multiple charging, ashing, then determining once by directly charging into pools of graphite furnace, was set up. The goal of concentrating samples and avoiding contamination as well as raising sensitivity were finally achieved. To prevent the background of purity water and regent in experiment from covering the ion concentration of the sample, the authors prepared the high purity water and regent to meet the requirement of the experiment by electrodialysis in series with distillation and below-boiling-point quartz distillation at pure worktable. Satisfactory results of linearity and detection limit were obtained. The detection limit with this method was 0. 086 microg x L(-1) for Na+. The recovery was 101%-104%.

  13. Effect of relative nanohole position on colour purity of ultrathin plasmonic subtractive colour filters.

    PubMed

    Sun, L B; Hu, X L; Zeng, Beibei; Wang, L S; Yang, S M; Tai, R Z; Fecht, H J; Zhang, D X; Jiang, J Z

    2015-07-31

    Plasmonic subtractive color filters through patterning periodic nanostructures on ultrathin Ag films deposited on a glass substrate, exhibiting good durability, simple fabrication, and flexible color tunability, have attracted considerable attention due to their tremendous potential applications. While previous studies have mainly focused on their extraordinary physical mechanisms, color purity, which is another key parameter for high quality imaging applications, has been much less investigated. In this work, we demonstrate that the relative position of nanoholes patterned on ultrathin Ag films can largely affect the color purity of plasmonic subtractive color filters. The calculated results agree reasonably well with the experimental data, revealing that the purity of subtractive colors can be improved by changing the nanohole arrays from square lattice to triangular lattice without reducing transmission at visible frequencies. In addition, underlying mechanisms are clarified by systematically analyzing the dominant valley in transmission spectra.

  14. Microstructure Evolution in High Purity Aluminum Single Crystal Processed by Equal Channel Angular Pressing (ECAP)

    PubMed Central

    Dong, Jinfang; Dong, Qing; Dai, Yongbing; Xing, Hui; Han, Yanfeng; Ma, Jianbo; Zhang, Jiao; Wang, Jun; Sun, Baode

    2017-01-01

    Aluminum single crystal with 99.999% purity was deformed at room temperature by equal channel angular pressing (ECAP) up to 16 passes. Grain size and misorientation of processed samples were quantitatively characterized by TEM and EBSD. The results show that the refinement efficiency of high purity aluminum single crystal was poor in the initial stage. Extrusion by fewer ECAP passes (n ≤ 8) resulted in only elongated grains containing a large number of subgrains and small misorientations between grains. Stable microstructures of nearly equiaxed grains with high misorientations were obtained by 15 passages, indicating that the initial extremely coarse grains and highly uniform grain orientation are not conducive to the accumulation of strain energy. The initial state of high purity aluminum has a significant effect on the refining efficiency of the ECAP process. PMID:28772447

  15. Optical fiber design with orbital angular momentum light purity higher than 99.9.

    PubMed

    Zhang, Zhishen; Gan, Jiulin; Heng, Xiaobo; Wu, Yuqing; Li, Qingyu; Qian, Qi; Chen, Dongdan; Yang, Zhongmin

    2015-11-16

    The purity of the synthesized orbital-angular-momentum (OAM) light in the fiber is inversely proportional to channel crosstalk level in the OAM optical fiber communication system. Here the relationship between the fiber structure and the purity is firstly demonstrated in theory. The graded-index optical fiber is proposed and designed for the OAM light propagation with the purity higher than 99.9%. 16 fiber modes (10 OAM modes) have been supported by a specific designed graded-index optical fiber with dispersion less than 35 ps/(km∙nm). Such fiber design has suppressed the intrinsic crosstalk to be lower than -30 dB, and can be potentially used for the long distance OAM optical communication system.

  16. Impurity distribution in high purity germanium crystal and its impact on the detector performance

    NASA Astrophysics Data System (ADS)

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

    High-purity germanium crystals were grown in a hydrogen atmosphere using the Czochralski method. The axial and radial distributions of impurities in the crystals were measured by Hall effect and Photo-thermal ionization spectroscopy (PTIS). Amorphous semiconductor contacts were deposited on the germanium crystals to make detectors. Three planar detectors were fabricated from three crystals with different net carrier concentrations (1.7, 7.9 and 10x1010 cm-3). We evaluated the electrical and spectral performance of three detectors. Measurements of gamma-ray spectra from 137Cs, 241Am and 60Co sources demonstrate that the detectors have excellent energy resolution. The relationship between the impurities and detector's energy resolution was analyzed. Keywords: High-purity germanium crystal, High-purity germanium detector This work is supported by DOE grant DE-FG02-10ER46709 and the state of South Dakota..

  17. Efavirenz related compounds preparation by hydrolysis procedure: setting reference standards for chromatographic purity analysis.

    PubMed

    Ribeiro, José Antônio de Aquino; de Campos, Ligia Maria Moreira; Alves, Ricardo José; Lages, Gustavo Portela; Pianetti, Gerson Antônio

    2007-01-04

    A simple procedure for obtaining and purifying two degradation products of efavirenz (amino alcohol and quinoline derivatives) from drug substance hydrolysis is described. These impurities are known to exhibit very different UV absorbance properties from those of the parent compound, making determination using a quantitation factor (QF) inaccurate. The obtained hydrolysis products were characterized by physicochemical methods to assure identity, purity and strength. Quinoline derivative was of high purity degree (100%) and amino alcohol was 98.74% pure. Both were set as reference standards in chromatographic related compounds test for efavirenz drug substance and tablets analyses.

  18. Method for growing low defect, high purity crystalline layers utilizing lateral overgrowth of a patterned mask

    NASA Technical Reports Server (NTRS)

    Morrison, Andrew D. (Inventor); Daud, Taher (Inventor)

    1986-01-01

    A method for growing a high purity, low defect layer of semiconductor is described. This method involves depositing a patterned mask of a material impervious to impurities of the semiconductor on a surface of a blank. When a layer of semiconductor is grown on the mask, the semiconductor will first grow from the surface portions exposed by the openings in the mask and will bridge the connecting portions of the mask to form a continuous layer having improved purity, since only the portions overlying the openings are exposed to defects and impurities. The process can be iterated and the mask translated to further improve the quality of grown layers.

  19. Enhanced color purity of blue OLEDs based on well-design structure

    NASA Astrophysics Data System (ADS)

    Du, Qianqian; Wang, Wenjun; Li, Shuhong; Wang, Qingru; Xia, Shuzhen; Zhang, Bingyuan; Wang, Minghong; Fan, Quli

    2016-09-01

    We have fabricated blue organic light-emitting devices (OLEDs) with higher color purity and stability by optimizing the structure of the Glass/ITO/NPB(50 nm)/ BCzVBi (30 nm)/ TPBi (x nm)/Alq3(20 nm)/LiF/Al. The results show that the introducing of hole blocking layer(HBL) TPBi greatly can improve not only the color purity but the color stability, which owe to its higher the Highest Occupied Molecular Orbital (HOMO) energy levels of 6.2 eV. We expect our work will be useful to optimizing the blue OLEDs structure to enhancing the color property.

  20. Mechanical Strength and Biocompatibility of Ultrafine-Grained Commercial Purity Titanium

    PubMed Central

    Estrin, Yuri; Kim, Hyoun-Ee; Lapovok, Rimma; Ng, Hoi Pang; Jo, Ji-Hoon

    2013-01-01

    The effect of grain refinement of commercial purity titanium by equal channel angular pressing (ECAP) on its mechanical performance and bone tissue regeneration is reported. In vivo studies conducted on New Zealand white rabbits did not show an enhancement of biocompatibility of ECAP-modified titanium found earlier by in vitro testing. However, the observed combination of outstanding mechanical properties achieved by ECAP without a loss of biocompatibility suggests that this is a very promising processing route to bioimplant manufacturing. The study thus supports the expectation that commercial purity titanium modified by ECAP can be seen as an excellent candidate material for bone implants suitable for replacing conventional titanium alloy implants. PMID:23936857

  1. Linearly polarized orbital angular momentum mode purity measurement in optical fibers.

    PubMed

    Jiang, Youchao; Ren, Guobin; Li, Haisu; Tang, Min; Liu, Yu; Wu, Yue; Jian, Wei; Jian, Shuisheng

    2017-03-01

    We presented a simple method for measuring the mode purity of linearly polarized orbital angular momentum (OAM) modes in optical fibers. The method is based on the analysis of OAM beam projections filtered by a polarizer. The amplitude spectrum and phase spectrum of a data ring derived from the beam pattern are obtained by Fourier transform. Then the coefficients of the mixed electric field expression can be determined and the mode purity can be obtained. The proposed method is validated and it is experimentally demonstrated in a two-mode fiber.

  2. NIST-Traceable NMR Method to Determine Quantitative Weight Percentage Purity of Nitrogen Mustard HN-1 Feedstock Samples

    DTIC Science & Technology

    2014-06-01

    ECBC-TR-1251 NIST-TRACEABLE NMR METHOD TO DETERMINE QUANTITATIVE WEIGHT PERCENTAGE PURITY OF NITROGEN MUSTARD HN-1 FEEDSTOCK SAMPLES David J...Determine Quantitative Weight Percentage Purity of Nitrogen Mustard HN-1 Feedstock Samples 5a. CONTRACT NUMBER W911SR-10-D-0004 5b. GRANT NUMBER 5c...using NMR with proton detection is described to determine the weight percent purity of feedstock samples of nitrogen mustard , HN-1. 15. SUBJECT

  3. 3 Neutrino mass experiments fit a strange 3 + 3 model, but will KATRIN reveal the model's unique 3-part signature?

    NASA Astrophysics Data System (ADS)

    Ehrlich, R.

    2016-12-01

    Evidence is presented in support of an unconventional 3 + 3 model of the neutrino mass eigenstates with specific m2 > 0 and m2 < 0 masses. The two large m2 > 0 masses of the model were originally suggested based on a SN 1987A analysis, and they were further supported by several dark matter fits. The new evidence for one of the m2 > 0 mass values comes from an analysis of published data from the three most precise tritium β - decay experiments. The KATRIN experiment by virtue of a unique 3-part signature should either confirm or reject the model in its entirety.

  4. Low temperature recombination and trapping analysis in high purity gallium arsenide by microwave photodielectric techniques

    NASA Technical Reports Server (NTRS)

    Khambaty, M. B.; Hartwig, W. H.

    1972-01-01

    Some physical theories pertinent to the measurement properties of gallium arsenide are presented and experimental data are analyzed. A model for explaining recombination and trapping high purity gallium arsenide, valid below 77 K is assembled from points made at various places and an appraisal is given of photodielectric techniques for material property studies.

  5. Cleansing the Superdome: The Paradox of Purity and Post-Katrina Guilt

    ERIC Educational Resources Information Center

    Grano, Daniel A.; Zagacki, Kenneth S.

    2011-01-01

    The reopening of the New Orleans Superdome after Hurricane Katrina on Monday Night Football dramatized problematic rhetorical, visual, and spatial norms of purification rituals bound up in what Burke calls the paradox of purity. Hurricane Katrina was significant as a visually traumatic event in large part because it signified the ghetto as a…

  6. Production of High-purity Radium-223 from Legacy Actinium-Beryllium Neutron Sources

    SciTech Connect

    Z. Soderquist, Chuck; K. McNamara, Bruce; R. Fisher, Darrell

    2012-06-01

    Radium-223 is a short-lived alpha-particle-emitting radionuclides with potential applications in cancer treatment. Research to develop new radiopharmaceuticals employing 223Ra has been hindered by poor availability due to the small quantities of parent actinium-227 available world-wide. The purpose of this study was to develop innovative and cost-effective methods to obtain high-purity 223Ra from 227Ac. We obtained 227Ac from two surplus actinium-beryllium neutron generators. We retrieved the actinium/beryllium buttons from the sources and dissolved them in a sulfuric-nitric acid solution. A crude actinium solid was recovered from the solution by coprecipitation with thorium fluoride, leaving beryllium in solution. The crude actinium was purified to provide about 40 milligrams of actinium nitrate using anion exchange in methanol-water-nitric acid solution. The purified actinium was then used to generate high-purity 223Ra. We extracted 223Ra using anion exchange in a methanol-water-nitric acid solution. After the radium was separated, actinium and thorium were then eluted from the column and dried for interim storage. This single-pass separation produces high purity, carrier-free 223Ra product, and does not disturb the 227Ac/227Th equilibrium. A high purity, carrier-free 227Th was also obtained from the actinium using a similar anion exchange in nitric acid. These methods enable efficient production of 223Ra for research and new alpha-emitter radiopharmaceutical development.

  7. Production of high-purity radium-223 from legacy actinium-beryllium neutron sources.

    PubMed

    Soderquist, Chuck Z; McNamara, Bruce K; Fisher, Darrell R

    2012-07-01

    Radium-223 is a short-lived alpha-particle-emitting radionuclide with potential applications in cancer treatment. Research to develop new radiopharmaceuticals employing (223)Ra has been hindered by poor availability due to the small quantities of parent actinium-227 available world-wide. The purpose of this study was to develop innovative and cost-effective methods to obtain high-purity (223)Ra from (227)Ac. We obtained (227)Ac from two surplus actinium-beryllium neutron generators. We retrieved the actinium/beryllium buttons from the sources and dissolved them in a sulfuric-nitric acid solution. A crude actinium solid was recovered from the solution by coprecipitation with thorium fluoride, leaving beryllium in solution. The crude actinium was purified to provide about 40 milligrams of actinium nitrate using anion exchange in methanol-water-nitric acid solution. The purified actinium was then used to generate high-purity (223)Ra. We extracted (223)Ra using anion exchange in a methanol-water-nitric acid solution. After the radium was separated, actinium and thorium were then eluted from the column and dried for interim storage. This single-pass separation produces high purity, carrier-free (223)Ra product, and does not disturb the (227)Ac/(227)Th equilibrium. A high purity, carrier-free (227)Th was also obtained from the actinium using a similar anion exchange in nitric acid. These methods enable efficient production of (223)Ra for research and new alpha-emitter radiopharmaceutical development.

  8. Cross Purposes: Love and Purity at a Puerto Rican Protestant High School

    ERIC Educational Resources Information Center

    Seale-Collazo, James

    2013-01-01

    A "native" Christian ethnographer finds religious education at this church-sponsored school to pursue two distinct, and occasionally conflicting, curricula: "love" and "purity." The curriculum of love draws on what Turner called liminality and communitas in an effort to promote spiritual "encounters with…

  9. Judgments of moral responsibility and wrongness for intentional and accidental harm and purity violations.

    PubMed

    Parkinson, Mary; Byrne, Ruth M J

    2017-01-31

    Two experiments examine whether people reason differently about intentional and accidental violations in the moral domains of harm and purity, by examining moral responsibility and wrongness judgments for violations that affect others or the self. The first experiment shows that intentional violations are judged to be worse than accidental ones, regardless of whether they are harm or purity violations-for example, Sam poisons his colleague versus Sam eats his dog, when participants judge how morally responsible was Sam for what he did, or how morally wrong was what Sam did. The second experiment shows that violations of others are judged to be worse than violations of the self, regardless of whether they are harm or purity violations, when their content and context is matched-for example, on a tropical holiday Sam orders poisonous starfruit for dinner for his friend, or for himself, versus on a tropical holiday Sam orders dog meat for dinner for his friend, or for himself. Moral reasoning is influenced by whether the violation was intentional or accidental, and whether its target was the self or another person, rather than by the moral domain, such as harm or purity.

  10. 7 CFR 201.51a - Special procedures for purity analysis.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Special procedures for purity analysis. (a) The Uniform Blowing Procedure shall be used for the separation... Blowing Procedure. (2) To determine the blowing point for these procedures, individual calibration samples... side-oats grama. (i) The blowing point for Canada bluegrass shall be the same as the blowing...

  11. 7 CFR 201.51a - Special procedures for purity analysis.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Special procedures for purity analysis. (a) The Uniform Blowing Procedure shall be used for the separation... Blowing Procedure. (2) To determine the blowing point for these procedures, individual calibration samples... side-oats grama. (i) The blowing point for Canada bluegrass shall be the same as the blowing...

  12. 7 CFR 201.51a - Special procedures for purity analysis.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Special procedures for purity analysis. (a) The Uniform Blowing Procedure shall be used for the separation... Blowing Procedure. (2) To determine the blowing point for these procedures, individual calibration samples... side-oats grama. (i) The blowing point for Canada bluegrass shall be the same as the blowing...

  13. 7 CFR 201.51a - Special procedures for purity analysis.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Special procedures for purity analysis. (a) The Uniform Blowing Procedure shall be used for the separation... Blowing Procedure. (2) To determine the blowing point for these procedures, individual calibration samples... side-oats grama. (i) The blowing point for Canada bluegrass shall be the same as the blowing...

  14. 7 CFR 201.51a - Special procedures for purity analysis.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Special procedures for purity analysis. (a) The Uniform Blowing Procedure shall be used for the separation... Blowing Procedure. (2) To determine the blowing point for these procedures, individual calibration samples... side-oats grama. (i) The blowing point for Canada bluegrass shall be the same as the blowing...

  15. Cross Purposes: Love and Purity at a Puerto Rican Protestant High School

    ERIC Educational Resources Information Center

    Seale-Collazo, James

    2013-01-01

    A "native" Christian ethnographer finds religious education at this church-sponsored school to pursue two distinct, and occasionally conflicting, curricula: "love" and "purity." The curriculum of love draws on what Turner called liminality and communitas in an effort to promote spiritual "encounters with…

  16. Changes in EEG mean frequency and spectral purity during spontaneous alpha blocking.

    PubMed

    Goncharova, I I; Barlow, J S

    1990-09-01

    Spontaneously occurring brief periods of lower voltage irregular activity occurring amid a background of alpha activity (i.e., alpha blocking) in eyes-closed resting occipital EEG recordings from 32 healthy human subjects have been investigated to determine the extent of changes of mean frequency and of spectral purity (degree of regularity/irregularity of the EEG activity) during such periods. New methods for determining mean frequency and spectral purity (the latter as a new measure, the Spectral Purity Index, which has a maximum value of 1.0 for a pure sine wave) permit their conjoint evaluation over a 0.5 sec window that is advanced along the EEG in 0.1 sec steps, thus permitting almost continuous feature extraction. The findings indicate that, although spectral purity invariably decreased during the periods of lower voltage irregular activity, the mean frequency remained relatively unaltered, i.e., it remained unchanged or it increased or decreased slightly but at most by 2.5 Hz. These results suggest that, at least for the periods of lower voltage irregular activity occurring spontaneously amid an alpha background during eyes-closed occipital EEG recordings, it may be inaccurate (as some authors have already suggested) to use the term 'low-voltage fast (or beta) activity.'

  17. Cleansing the Superdome: The Paradox of Purity and Post-Katrina Guilt

    ERIC Educational Resources Information Center

    Grano, Daniel A.; Zagacki, Kenneth S.

    2011-01-01

    The reopening of the New Orleans Superdome after Hurricane Katrina on Monday Night Football dramatized problematic rhetorical, visual, and spatial norms of purification rituals bound up in what Burke calls the paradox of purity. Hurricane Katrina was significant as a visually traumatic event in large part because it signified the ghetto as a…

  18. Comparison of analytical techniques for purity evaluation of single-walled carbon nanotubes.

    PubMed

    Itkis, Mikhail E; Perea, Daniel E; Jung, Richard; Niyogi, Sandip; Haddon, Robert C

    2005-03-16

    We compare popular analytical techniques, including scanning and transmission electron microscopy (SEM and TEM), thermogravimetric analysis (TGA), and Raman and near-infrared (NIR) spectroscopy, for the evaluation of the purity of bulk quantities of single-walled carbon nanotubes (SWNTs). Despite their importance as imaging techniques, SEM and TEM are not capable of quantitatively evaluating the purity of typical inhomogeneous bulk SWNT samples because the image frame visualizes less than 1 pg of SWNT material; furthermore, there is no published algorithm to convert such images into numerical data. The TGA technique is capable of measuring the amount of metal catalyst in an SWNT sample, but does not provide an unambiguous separation between the content of SWNTs and carbonaceous impurities. We discuss the utilization of solution-phase near-infrared spectroscopy and solution-phase Raman spectroscopy to quantitatively compare arbitrary samples of bulk SWNT materials of different purities. The primary goal of this paper is to provide the chemical community with a realistic evaluation of current analytical tools for the purity evaluation of a bulk sample of SWNTs. The secondary goal is to draw attention to the growing crisis in the SWNT industry as a result of the lack of quality control and the misleading advertising by suppliers of this material.

  19. Carrier-free {sup 33}P-orthophosphoric acid of special purity

    SciTech Connect

    Kuznetsova, N.V.; Vinogradova, R.B.; Kalugin, V.V.

    1993-12-31

    Carrier-free phosphorus 33-ortho-phosphoric acid of special purity is applied in molecular biology for phosphorus 33 nucleoside-phosphate synthesis. The Research Institute of Atomic Reactors (RIAR) has the powerful reactor base and the effective technology to obtain the high-quality preparation and increase the production amount up to 50-100 Ci per year. The process is described.

  20. Efficient continuous synthesis of high purity deep eutectic solvents by twin screw extrusion.

    PubMed

    Crawford, D E; Wright, L A; James, S L; Abbott, A P

    2016-03-18

    Mechanochemical synthesis has been applied to the rapid synthesis of Deep Eutectic Solvents (DESs), including Reline 200 (choline chloride : urea, 1 : 2), in a continuous flow methodology by Twin Screw Extrusion (TSE). This gave products in higher purity and with Space Time Yields (STYs), four orders of magnitude greater than for batch methods.

  1. Comparison of the purity and vitality of natural killer cells with different isolation kits.

    PubMed

    Wang, Guangchuan; Yu, Guang; Wang, Dongmei; Guo, Shengnan; Shan, Fengping

    2017-05-01

    Natural killer (NK) cells are innate lymphocytes that aid in the protection of the host from infectious diseases and cancer. In vitro studies of NK cells have provided a foundation for developing clinical adoptive NK-cell transferred immunotherapy against human tumors. To elucidate the functions and mechanisms of NK cell populations, it is important to develop an optimal, highly reproducible and reliable isolation method. The present comparative study was performed with four different NK cell isolation kits of magnetic bead labeling made by Miltenyi and Stemcell companies, including positive selection kits [cluster of differentiation (CD)-49b, using the monoclonal antibody DX5) MicroBeads] and negative selection kits. In addition, the viability of NK cells isinterleukin-2 (IL-2)-dependent in vitro and thus the concentration of IL-2 is critical for maintaining longer cell viability of NK cells. NK cell purity and viability after culturing, for 24, 48 or 72 h, with or without IL-2 (0, 100, 300 or 500 U/ml) was investigated in the present study. Purity of NK cells varied depending on the purification kit used, despite the same method being applied. Furthermore, more granulocytes were present in purified NK cells using Miltenyi sorting kits, particularly when using the negative selection kit. The main disadvantage of DX5-positive selection using the Stemcell and Miltenyi kits was that a high percentage of CD3ε(+) cells were mixed into the isolated NK cells. Additionally, a significant difference of NK cell purity (P=0.003) was observed while purification was performed using different surface markers. As a consequence, the use of the positive selection kit was modified and subsequently a significantly higher purity (P=0.002) and yield (P=0.004) of NK cells was obtained. Moreover, the purity of NK cells and viability with or without a range of concentrations of IL-2 was compared. Results indicated that with a higher IL-2 concentration, the NK cell purity and viability

  2. Proximity to the US-Mexico border: a key to explaining geographic variation in US methamphetamine, cocaine and heroin purity.

    PubMed

    Cunningham, James K; Maxwell, Jane Carlisle; Campollo, Octavio; Cunningham, Kathryn I; Liu, Lon-Mu; Lin, Hui-Lin

    2010-10-01

    Although illicit drug purity is a widely discussed health risk, research explaining its geographic variation within a country is rare. This study examines whether proximity to the US-Mexico border, the United States' primary drug import portal, is associated with geographic variation in US methamphetamine, heroin and cocaine purity. Distances (proximity) between the US-Mexico border and locations of methamphetamine, cocaine and heroin seizures/acquisitions (n = 239,070) recorded in STRIDE (System to Retrieve Information from Drug Evidence) were calculated for the period of 1990-2004. The association of drug purity with these distances and other variables, including time and seizure/acquisition size, was examined using hierarchical multivariate linear modeling (HMLM). Coterminous United States. Methamphetamine, cocaine and heroin purity generally decreased with distance from the US-Mexico border. Heroin purity, however, after initially declining with distance, turned upwards-a U-shaped association. During 2000-04, methamphetamine purity also had a U-shaped association with distance. For each of the three drugs, temporal changes in the purity of small acquisitions (<10 g) were typically more dynamic in areas closer to the US-Mexico border. Geographic variance in methamphetamine, cocaine and heroin purity throughout the coterminous United States was associated with US-Mexico border proximity. The U-shaped associations between border-distance and purity for heroin and methamphetamine may be due to imports of those drugs via the eastern United States and southeast Canada, respectively. That said, areas closer to the US-Mexico border generally had relatively high illicit drug purity, as well as more dynamic change in the purity of small ('retail level') drug amounts. © 2010 The Authors, Addiction © 2010 Society for the Study of Addiction.

  3. Low Temperature Magnetic Calorimeters For Neutrino Mass Direct Measurement

    NASA Astrophysics Data System (ADS)

    Gastaldo, L.; Porst, J. P.; von Seggern, F.; Kirsch, A.; Ranitzsch, P.; Fleischmann, A.; Enss, C.; Seidel, G. M.

    2009-12-01

    In the last years the mixing of the three neutrino flavor eigenstates through a unitary matrix has been experimentally proved. Presently one of the greatest challenges in neutrino physics is to establish the absolute value of the masses of the three neutrino mass eigenstates. The kinematic determination of electron neutrino and antineutrino mass by means of the analysis of calorimetric spectra of isotopes which undergo a beta or electron-capture decay, with especially low energy available for the decay itself, represents an interesting method. In fact this method is less affected by theoretical models defining branching ratio among different decay modes. For the beta decay the isotope with the lowest Q-value present in nature is the 187Re (Q about 2.5 keV) while for the electron capture decay the best candidate known is the 163Ho (Q about 2.5 keV). Since those experiments need to be extremely precise, they might suffer from unexpected systematic errors. It is therefore important to investigate in detail the performance of the detectors and the calorimetric spectrum. We present our results obtained with low temperature magnetic calorimeters designed for measuring low energy beta and electron capture spectra. We also discuss problematic and the possibly present systematic uncertainties using this kind of detectors.

  4. Preparation and characterization of (10)B boric acid with high purity for nuclear industry.

    PubMed

    Zhang, Weijiang; Liu, Tianyu; Xu, Jiao

    2016-01-01

    Boric acid is often added into coolant as neutron capture agent for pressurized water reactor, whose amount is influenced by its abundance and purity. Therefore, the preparation of enriched (10)B boric acid with high purity is beneficial to nuclear industry. (10)B is also used in developing tumor-specific boronated drugs in boron neutron capture therapy. The boronated drug can be administered to patient intravenously, intratumorally, or deposited at tumor site in surgical excision. Thus, enriched (10)B boric acid is of practical significance in the field of medicine. Self-made boron trifluoride-methanol-complex solution was selected as one of the experimental reagents, and the preparation of (10)B acid was realized by one-step reaction for the complexes with water and calcium chloride. The determination of electrical conductivity in reaction process proves that the optimum reaction time was 16-20 h. Furthermore, the effect of reaction time, ratio of calcium chloride to complex as well as the amount of water on the purity and yield of boric acid was investigated. Finally, the optimum reaction time was 20 h, the optimal solid-liquid ratio (molar ratio) was 3:1, and the amount of water was 1 L of deionized water for each mol of the complex. H2O2 was added in the reaction process to remove Fe(2+). After recrystallization, IR spectra of (10)B boric acid was measured and compared with standard to verify the product of boric acid. The feasibility of the preparation method was determined by the detection of XRD of boric acid. To observe the morphology by polarizing microscope, crystal structure was obtained. The purity of the final product is 99.95 %, and the yield is 96.47 %. The ion concentration of boric acid accords with the national standard of high purity, which was determined by ICP.

  5. [Purity Detection Model Update of Maize Seeds Based on Active Learning].

    PubMed

    Tang, Jin-ya; Huang, Min; Zhu, Qi-bing

    2015-08-01

    Seed purity reflects the degree of seed varieties in typical consistent characteristics, so it is great important to improve the reliability and accuracy of seed purity detection to guarantee the quality of seeds. Hyperspectral imaging can reflect the internal and external characteristics of seeds at the same time, which has been widely used in nondestructive detection of agricultural products. The essence of nondestructive detection of agricultural products using hyperspectral imaging technique is to establish the mathematical model between the spectral information and the quality of agricultural products. Since the spectral information is easily affected by the sample growth environment, the stability and generalization of model would weaken when the test samples harvested from different origin and year. Active learning algorithm was investigated to add representative samples to expand the sample space for the original model, so as to implement the rapid update of the model's ability. Random selection (RS) and Kennard-Stone algorithm (KS) were performed to compare the model update effect with active learning algorithm. The experimental results indicated that in the division of different proportion of sample set (1:1, 3:1, 4:1), the updated purity detection model for maize seeds from 2010 year which was added 40 samples selected by active learning algorithm from 2011 year increased the prediction accuracy for 2011 new samples from 47%, 33.75%, 49% to 98.89%, 98.33%, 98.33%. For the updated purity detection model of 2011 year, its prediction accuracy for 2010 new samples increased by 50.83%, 54.58%, 53.75% to 94.57%, 94.02%, 94.57% after adding 56 new samples from 2010 year. Meanwhile the effect of model updated by active learning algorithm was better than that of RS and KS. Therefore, the update for purity detection model of maize seeds is feasible by active learning algorithm.

  6. Final report on key comparison CCQM-K55.c (L-(+)-Valine): Characterization of organic substances for chemical purity

    NASA Astrophysics Data System (ADS)

    Westwood, Steven; Josephs, Ralf; Choteau, Tiphaine; Daireaux, Adeline; Wielgosz, Robert; Davies, Stephen; Moad, Michael; Chan, Benjamin; Muñoz, Amalia; Conneely, Patrick; Ricci, Marina; Pires do Rego, Eliane Cristina; Garrido, Bruno C.; Violante, Fernando G. M.; Windust, Anthony; Dai, Xinhua; Huang, Ting; Zhang, Wei; Su, Fuhai; Quan, Can; Wang, Haifeng; Lo, Man-fung; Wong, Wai-fun; Gantois, Fanny; Lalerle, Béatrice; Dorgerloh, Ute; Koch, Matthias; Klyk-Seitz, Urszula-Anna; Pfeifer, Dietmar; Philipp, Rosemarie; Piechotta, Christian; Recknagel, Sebastian; Rothe, Robert; Yamazaki, Taichi; Zakaria, Osman Bin; Castro, E.; Balderas, M.; González, N.; Salazar, C.; Regalado, L.; Valle, E.; Rodríguez, L.; Ángel Laguna, L.; Ramírez, P.; Avila, M.; Ibarra, J.; Valle, L.; Pérez, M.; Arce, M.; Mitani, Y.; Konopelko, L.; Krylov, A.; Lopushanskaya, E.; Tang Lin, Teo; Liu, Qinde; Tong Kooi, Lee; Fernandes-Whaley, Maria; Prevoo-Franzsen, Désirée; Nhlapo, Nontete; Visser, Ria; Kim, Byungjoo; Lee, Hwashim; Kankaew, Pornhatai; Pookrod, Preeyaporn; Sudsiri, Nittaya; Shearman, Kittiya; Ceyhan Gören, Ahmet; Bilsel, Gökhan; Yilmaz, Hasibe; Bilsel, Mine; Çergel, Muhiddin; Gonca Çoskun, Fatma; Uysal, Emrah; Gündüz, Simay; Ün, Ilker; Warren, John; Bearden, Daniel W.; Bedner, Mary; Duewer, David L.; Lang, Brian E.; Lippa, Katrice A.; Schantz, Michele M.; Sieber, John R.

    2014-01-01

    Under the auspices of the Organic Analysis Working Group (OAWG) of the Comité Consultatif pour la Quantité de Matière (CCQM) a key comparison, CCQM K55.c, was coordinated by the Bureau International des Poids et Mesures (BIPM) in 2012. Twenty National Measurement Institutes or Designated Institutes and the BIPM participated. Participants were required to assign the mass fraction of valine present as the main component in the comparison sample for CCQM-K55.c. The comparison samples were prepared from analytical grade L-valine purchased from a commercial supplier and used as provided without further treatment or purification. Valine was selected to be representative of the performance of a laboratory's measurement capability for the purity assignment of organic compounds of low structural complexity [molecular weight range 100-300] and high polarity (pKOW > -2). The KCRV for the valine content of the material was 992.0 mg/g with a combined standard uncertainty of 0.3 mg/g. The key comparison reference value (KCRV) was assigned by combination of KCRVs assigned from participant results for each orthogonal impurity class. The relative expanded uncertainties reported by laboratories having results consistent with the KCRV ranged from 1 mg/g to 6 mg/g when using mass balance based approaches alone, 2 mg/g to 7 mg/g using quantitative 1H NMR (qNMR) based approaches and from 1 mg/g to 2.5 mg/g when a result obtained by a mass balance method was combined with a separate qNMR result. The material provided several analytical challenges. In addition to the need to identify and quantify various related amino acid impurities including leucine, isoleucine, alanine and α-amino butyrate, care was required to select appropriate conditions for performing Karl Fischer titration assay for water content to avoid bias due to in situ formation of water by self-condensation under the assay conditions. It also proved to be a challenging compound for purity assignment by qNMR techniques

  7. Separation of high-purity syringol and acetosyringone from rice straw-derived bio-oil by combining the basification-acidification process and column chromatography.

    PubMed

    Hao, Shilai; Chen, Kaifei; Cao, Leichang; Zhu, Xiangdong; Luo, Gang; Zhang, Shicheng; Chen, Jianmin

    2016-10-01

    Numerous technologies have been used to reclaim valuable chemicals from bio-oil. In this study, a combination of the basification-acidification process and column chromatography was employed for the separation of high-purity syringol and acetosyringone from rice straw-derived bio-oil. The optimal conditions for the basification-acidification process and the possible precipitation mechanism of the basification were explored. The results showed the following as the optimal conditions for the basification process: mass ratio of calcium hydroxide (Ca(OH)2 ) to bio-oil, 2.0; reaction temperature, 70°C; and reaction time, 30 min. The results also showed that 1.6 mol of hydrochloric acid (HCl) per gram of bio-oil was optimal for the acidification. The precipitation was found to proceed via a possible mechanism involving the reaction of the phenolic compounds in the bio-oil with Ca(OH)2 to produce a precipitate. After further separation by column chromatography, purities of 91.4 and 96.2% (from gas chromatography-mass spectrometry) were obtained for syringol and acetosyringone, respectively. Their recoveries for the whole process were 73.0 and 39.3%, respectively.

  8. General eigenstates of Maxwell's equations in a two-constituent composite medium and their application to a calculation of the local electric field in a flat-slab microstructure

    NASA Astrophysics Data System (ADS)

    Farhi, Asaf; Bergman, David J.

    2016-09-01

    An exact calculation of the local electric field E(r) is described for the case of an external current or plane wave source in a setup of an E1, μ1 slab in an E2, μ2 medium. For this purpose we first calculate all the general eigenstates of the full Maxwell equations. These eigenstates are then used to develop an exact expansion for the physical values of E(r) in the system characterized by physical values of E1, E2, μ1, and μ2. Results are compared with those of a previous calculation of the local field where μ = 1 everywhere. Numerical results are shown for the eigenvalues in practically important configurations where attaining an optical image with sub-wavelength resolution has practical significance. We show that the k >> k2 components are enhanced for the TM field when E1/E2 = -1 and for the TE field when μ1/μ2 = -1 where the enhancement of the evanescent waves starts from lower k values as we approach a setup with both E1/E2 = -1 and μ1/μ2 = -1. We also show that the eigenfunctions for the setup where μ = 1 everywhere correspond to configurations of 3D phased arrays.

  9. Mean-field dynamics of a Bose-Einstein condensate in a time-dependent triple-well trap: Nonlinear eigenstates, Landau-Zener models, and stimulated Raman adiabatic passage

    SciTech Connect

    Graefe, E. M.; Korsch, H. J.; Witthaut, D.

    2006-01-15

    We investigate the dynamics of a Bose-Einstein condensate in a triple-well trap in a three-level approximation. The interatomic interactions are taken into account in a mean-field approximation (Gross-Pitaevskii equation), leading to a nonlinear three-level model. Additional eigenstates emerge due to the nonlinearity, depending on the system parameters. Adiabaticity breaks down if such a nonlinear eigenstate disappears when the parameters are varied. The dynamical implications of this loss of adiabaticity are analyzed for two important special cases: A three-level Landau-Zener model and the stimulated Raman adiabatic passage (STIRAP) scheme. We discuss the emergence of looped levels for an equal-slope Landau-Zener model. The Zener tunneling probability does not tend to zero in the adiabatic limit and shows pronounced oscillations as a function of the velocity of the parameter variation. Furthermore we generalize the STIRAP scheme for adiabatic coherent population transfer between atomic states to the nonlinear case. It is shown that STIRAP breaks down if the nonlinearity exceeds the detuning.

  10. Production of high-purity isomalto-oligosaccharides syrup by the enzymatic conversion of transglucosidase and fermentation of yeast cells.

    PubMed

    Pan, Yen-Chung; Lee, Wen-Chien

    2005-03-30

    A method for the production of high-purity isomalto-oligosaccharides (IMO) involving the transglucosylation by transglucosidase and yeast fermentation was proposed. The starch of rice crumbs was enzymatically liquefied and saccharified, and then converted to low-purity IMO syrup by transglucosylation. The low-purity IMO produced either from rice crumbs or tapioca flour as the starch source could be effectively converted to high-purity IMO by yeast fermentation to remove the digestible sugars including glucose, maltose, and maltotriose. Both Saccharomyces carlsbergensis and Saccharomyces cerevisiae were able to ferment glucose in the IMO syrup. Cells of S. carlsbergensis harvested from the medium of malt juice were also able to ferment maltose and maltotriose. A combination of these two yeasts or S. carlsbergensis alone could be used to totally remove the digestible sugars in the IMO, coupled with the production of ethanol. The resultant high-purity IMO, including mainly isomaltose, panose, and isomaltotriose made up more than 98% w/w of the total sugars after a 3-day fermentation. When the low-purity IMO was produced from the starch of tapioca flour, 3-day fermentation under the same conditions resulted in IMO with purity lower than that from rice crumbs. For low-purity IMO from rice crumbs, fermentation with washed S. carlsbergensis cells harvested at log phase was the most effective. However, for the low-purity IMO from tapioca flour, incubation with S. cerevisiae for the first 24 h and then supplementing with an equal amount of S. carlsbergensis cells for further fermentation was the most effective approach for producing high-purity IMO.

  11. Effect of synthesis atmosphere, wetting, and compaction on the purity of AlB₂

    SciTech Connect

    Whittaker, Michael L.; Cutler, Raymond A.

    2013-05-01

    AlB₂ is attractive as an energetic fuel because of its large heat of combustion on a volumetric basis. The formation of AlB₂ from its elements is thermodynamically limited by decomposition into liquid aluminum and α-AlB₁₂ at temperatures approaching 950 °C, and kinetically limited in the reverse reaction, making synthesis of high-purity powders difficult. Minimizing unreacted Al and B makes AlB₂ more resistant to moisture degradation. AlB₂ yield for similarly prepared samples was observed to be significantly higher in He–6% H₂ or vacuum compared to a high-purity Ar atmosphere. Lower AlB₂ yield was generally associated with higher Al₂O₃ content in the reaction products, suggesting that poor Al wetting on oxide surfaces generated by the reaction of Al with B₂O₃ and other sources of oxygen prevented complete reaction. Compaction decreased the amount of oxygen available to the interior of the pellet, and the vacuum and He–6% H₂ environments reduced the amount of oxide impurities in the system, possibly by reducing or subliming them. By optimization of synthesis parameters the purity of AlB₂ was measured as 93 wt%, which was better than the previously reported bulk syntheses. Accounting for unreacted boron is important when using XRD to assess purity since the quantification of secondary phases, such as Al, Al₂O₃, and Al₃BC, allow the amount of boron, which is not easily detected in the scan, to be calculated. - Graphical abstract: Atmosphere and compaction pressure affect AlB₂ purity. Highlights: • Vacuum or He–6% H₂ yielded higher AlB₂ than Ar due to reduced Al₂O₃. • Compaction at 25 MPa prior to heating improved the AlB₂ yield. • XRD can be used to quantify AlB₂ if Al is used to assess the free B content. • Elimination of oxide impurities is the key to making higher purity AlB₂.

  12. Purity assessment problem in quantitative NMR--impurity resonance overlaps with monitor signal multiplets from stereoisomers.

    PubMed

    Malz, Frank; Jancke, Harald

    2006-06-01

    This paper describes the situation that can emerge when the signals to be evaluated in quantitative NMR measurements-so-called "monitor signals"--consist of several resonance lines from the stereoisomers of the analyte in addition to an impurity signal underneath. The monitor signal problem is demonstrated in the purity assessment of two samples of 2-(isopropylamino)-4-(ethylamino)-6-chloro-1,3,5-triazine (atrazine), a common herbizide which served as analyte in a CCQM intercomparison. It is shown that, in DMSO-d6 solution, a mixture of stereoisomers leads to several individual overlapping singlets, which are further split by spin-spin coupling. A measurement protocol was developed for finding and identifying an impurity that has a signal that is positioned precisely beneath the methyl signal chosen as the monitor signal in one of the samples. Quantitative NMR purity assessment is still possible in this special case, but with higher uncertainty.

  13. Cu2ZnSnS4 absorption layers with controlled phase purity.

    PubMed

    Su, Chia-Ying; Chiu, Chiu-Yen; Ting, Jyh-Ming

    2015-03-24

    We report the synthesis and characterization of Cu2ZnSnS4 (CZTS) with controlled phase purity. The precursor was first prepared using sequential electrodeposition of Cu, Zn, and Sn in different orders. The Cu/(Sn+Zn) ratio in each stacking order was also varied. The precursor was subjected to annealing at 200°C and sulfurization at 500°C in a 5%-H2S/Ar atmosphere for the formation of CZTS. The phase evolutions during the electrodeposition and annealing stages, and the final phase formation at the sulfurization stage were examined using both x-ray diffractometry and Raman spectroscopy, both of which are shown to be complimentary tools for phase identification. Detailed growth path is therefore reported. We also demonstrate by controlling the stacking order and the Cu/(Sn+Zn) ratio, CZTS with a phase purity as high as 93% is obtained.

  14. Detection of moisture content in high-purity ammonia by means of diode-laser spectroscopy

    NASA Astrophysics Data System (ADS)

    Berezin, A. G.; Nadezhdinskii, A. I.; Ponurovskii, Y. Y.; Stavrovskii, D. B.; Vyazov, I. E.; Kotkov, A. P.; Ivanov, V. A.; Grishnova, N. D.; Polezhaev, D. M.; Sidorov, V. A.; Kotkov, D. A.

    2008-02-01

    The aim of this work was the development of an as-simple-as-possible instrument for trace moisture concentration measurements in high-purity ammonia. A near-infrared diode-laser-based instrument has been applied to measure the humidity in a process of on-line detection of water in ammonia during industrial purification. The results of water concentration measurements were compared with alternative techniques (primarily dew-point detection) and good agreement was achieved. The long-term sensitivity of such a diode-laser-based instrument was estimated to be 5 ppm. The calculation of the water concentration from measurements of the integrated volume of water contained in the heavy fraction, extracted during the purification process, yields an even lower detection limit of less than 0.1 ppm, depending on the initial ammonia purity.

  15. Map showing high-purity silica sand of Middle Ordovician age in the Midwestern states

    USGS Publications Warehouse

    Ketner, Keith B.

    1979-01-01

    Certain quartz sands of Middle Ordovician age in the Midwestern States are well known for their purity and are exploited for a wide variety of industrial uses. The principal Middle Ordovician formations containing high-purity sands are the St. Peter Sandstone which crops out extensively from Minnesota to Arkansas; the Everton Formation principally of Arkansas; and the Oil Creek, McLish, and Tulip Creek Formations (all of the Simpson Group) of Oklahoma. The St. Peter and sandy beds in the other formations are commonly called "sandstones," but a more appropriate term is "sands" for in most fresh exposures they are completely uncemented or very weakly cemented. On exposure to air, uncemented sands usually become "case hardened" where evaporating ground water precipitates mineral matter at the surface; but this is a surficial effect. This report summarizes the available information on the extent of exposures, range of grain size, and chemical composition of the Middle Ordovician sands.

  16. Radionuclidic purity tests in (18)F radiopharmaceutIcals production process.

    PubMed

    Dziel, Tomasz; Tymiński, Zbigniew; Sobczyk, Katarzyna; Walęcka-Mazur, Agata; Kozanecki, Przemysław

    2016-03-01

    Radionuclidic purity tests of (18)F radiopharmaceuticals (Na(18)F and fluorodeoxyglucose [(18)F]FDG) and radionuclide composition analysis of irradiated water [(18)O]H2O were performed. The measurements were conducted using a High-Purity Germanium (HPGe) detector and a liquid scintillation counter. Radionuclide identification and activity measurements were performed for samples from different stages of the production process. Most of the impurities were detected on QMA (quaternary methylammonium) anion exchange columns and in liquid wastes. Using liquid scintillation counting, the activity of (3)H resulting from the (18)O[p, (3)H](16)O reaction was determined. It was shown that all of the impurities were efficiently determined and eliminated in the radiopharmaceuticals synthesis process and that the final products meet the requirements set by relevant regulations. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Supply-side response to declining heroin purity: fentanyl overdose episode in New Jersey.

    PubMed

    Hempstead, Katherine; Yildirim, Emel O

    2014-06-01

    The inelastic price demand observations characteristic of illegal drug markets have led to the conclusion that the burden of a negative supply shock would be completely reflected to consumers. This paper argues that the increasing availability of prescription opioids may threaten heroin sellers' profit margin and force them to find alternative methods to compensate buyers in the event of a supply shock. We investigate the 2006 fentanyl overdose episode in New Jersey and argue that the introduction of non-pharmaceutical fentanyl, its spatial distribution, and the timing of overdose deaths may have been related to trends in heroin purity. Using medical examiner data, as well as data from the Drug Enforcement Administration, Office of Diversion Control on retail sales of prescription opioids in a negative binomial specification, we show that month-to-month fluctuations in heroin purity have a significant effect on fentanyl-related overdoses, particularly in those areas where prescription opioids are highly available.

  18. Fabrication of novel cryomill for synthesis of high purity metallic nanoparticles

    NASA Astrophysics Data System (ADS)

    Kumar, Nirmal; Biswas, Krishanu

    2015-08-01

    The successful preparation of free standing metal nanoparticles with high purity in bulk quantity is the pre-requisite for any potential application. This is possible by using ball milling at cryogenic temperature. However, the most of ball mills available in the market do not allow preparing high purity metal nanoparticles by this route. In addition, it is not possible to carry out in situ measurements of process parameters as well as diagnostic of the process. In the present investigation, we present a detailed study on the fabrication of a cryomill, which is capable of avoiding contaminations in the product. It also provides in situ measurements and diagnostic of the low temperature milling process. Online monitoring of the milling temperature and observation of ball motion are the important aspects in the newly designed mill. The nanoparticles prepared using this fabricated mill have been found to be free standing and also free from contaminations.

  19. Characterization of a high-purity germanium detector for small-animal SPECT.

    PubMed

    Johnson, Lindsay C; Campbell, Desmond L; Hull, Ethan L; Peterson, Todd E

    2011-09-21

    We present an initial evaluation of a mechanically cooled, high-purity germanium double-sided strip detector as a potential gamma camera for small-animal SPECT. It is 90 mm in diameter and 10 mm thick with two sets of 16 orthogonal strips that have a 4.5 mm width with a 5 mm pitch. We found an energy resolution of 0.96% at 140 keV, an intrinsic efficiency of 43.3% at 122 keV and a FWHM spatial resolution of approximately 1.5 mm. We demonstrated depth-of-interaction estimation capability through comparison of pinhole acquisitions with a point source on and off axes. Finally, a flood-corrected flood image exhibited a strip-level uniformity of less than 1%. This high-purity germanium offers many desirable properties for small-animal SPECT.

  20. Using Capillary Electrophoresis to Determine the Purity of Acetylsalicylic Acid Synthesized in the Undergraduate Laboratory

    NASA Astrophysics Data System (ADS)

    Welder, Frank; Colyer, Christa L.

    2001-11-01

    Capillary electrophoresis (CE), although a powerful analytical tool, has found only limited application in undergraduate laboratory study. In an effort to expose freshman and sophomore chemistry students to this technique, thereby giving them practical instrumental experience early in their careers, we propose to use CE in the analysis of student-synthesized acetylsalicylic acid (ASA). The synthesis of ASA from salicylic acid (SA) is a routine undergraduate laboratory, although students rarely have the opportunity to test the purity of their product. The CE method described herein provides students with a method to test purity and yield of their product and to determine the effect of aging on their sample. CE can accomplish this in a short period of time, with minimal disruption to the regular laboratory curriculum. Optimized separation conditions, limits of detection, and linear range for ASA and SA are also given.

  1. Hybrid microfiber-lithium-niobate nanowaveguide structures as high-purity heralded single-photon sources

    NASA Astrophysics Data System (ADS)

    Main, Philip; Mosley, Peter J.; Ding, Wei; Zhang, Lijian; Gorbach, Andrey V.

    2016-12-01

    We propose a compact, fiber-integrated architecture for photon-pair generation by parametric downconversion with unprecedented flexibility in the properties of the photons produced. Our approach is based on a thin-film lithium niobate nanowaveguide, evanescently coupled to a tapered silica microfiber. We demonstrate how controllable mode hybridization between the fiber and waveguide yields control over the joint spectrum of the photon pairs. We also investigate how independent engineering of the linear and nonlinear properties of the structure can be achieved through the addition of a tapered, proton-exchanged layer to the waveguide. This allows further refinement of the joint spectrum through custom profiling of the effective nonlinearity, drastically improving the purity of the heralded photons. We give details of a source design capable of generating heralded single photons in the telecom wavelength range with purity of at least 0.95, and we provide a feasible fabrication methodology.

  2. Widely tunable single photon source with high purity at telecom wavelength.

    PubMed

    Jin, Rui-Bo; Shimizu, Ryosuke; Wakui, Kentaro; Benichi, Hugo; Sasaki, Masahide

    2013-05-06

    We theoretically and experimentally investigate the spectral tunability and purity of photon pairs generated from spontaneous parametric down conversion in periodically poled KTiOPO(4) crystal with group-velocity matching condition. The numerical simulation predicts that the spectral purity can be kept higher than 0.81 when the wavelength is tuned from 1460 nm to 1675 nm, which covers the S-, C-, L-, and U-band in telecommunication wavelengths. We also experimentally measured the joint spectral intensity at 1565 nm, 1584 nm and 1565 nm, yielding Schmidt numbers of 1.01, 1.02 and 1.04, respectively. Such a photon source is useful for quantum information and communication systems.

  3. Radiotracer study of the preparation of high-purity lanthanum fluoride

    SciTech Connect

    Ewing, K.J.; Jaganathan, J.; Peitersen, L.; Aggarwal, I.D. ); Sommers, J.A.; Fahey, J.V. )

    1992-06-01

    This paper reports that the behavior of the impurities iron, cobalt, yttrium, and cerium is determined via radiotracer techniques for the preparation of high-purity lanthanum fluoride. The behavior of nickel and copper during the coprecipitation of a lanthanum nitrate solution is determined by graphite furnace atomic absorption spectrometric (GFAAS) analysis. There is no commercially available radiotracer for neodymium, a key impurity associated with absorption losses in fluoride glasses. However, the chemical behavior of neodymium and that of yttrium are very similar and, therefore, it is reasonable to assume that the behavior of yttrium throughout the processing is indicative of the behavior of neodymium. The concentrations of impurities in lanthanum nitrate, carbonate, and fluoride are estimated using the radiotracer and GFAAS data for each processing step. Results indicate that while high-purity lanthanum carbonate can be prepared, any impurities present in the lanthanum carbonate will be carried quantitatively into lanthanum fluoride upon hydrofluorination.

  4. Method to deliver ultra high purity helium gas to a use point

    SciTech Connect

    Graczk, L.S.; Francis, A.W.

    1988-08-30

    This patent describes a method to deliver helium gas to a use point comprising: (A) providing gaseous helium from a high pressure cylinder or tube into a storage container containing liquid helium; (B) passing the gaseous helium in heat exchange relation with the liquid helium to: (i) vaporize liquid helium, (ii) increase or maintain the helium pressure, and (iii) condense and/or solidify impurities out of the gaseous helium; (C) withdrawing ultra high purity helium gas comprising resulting vaporized helium and cleaned gaseous helium from the storage container; and (D) providing ultra high purity helium gas to a use point without need for further pressurization, the helium gas containing less than 10 ppm impurities.

  5. Comparison of Deformation in High-Purity Single/Large Grain and Polycrystalline Niobium Superconducting Cavities

    SciTech Connect

    Ganapati Rao Myneni; Peter Kneisel

    2005-07-10

    The current approach for the fabrication of superconducting radio frequency (SRF) cavities is to roll and deep draw sheets of polycrystalline high-purity niobium. Recently, a new technique was developed at Jefferson Laboratory that enables the fabrication of single-crystal high-purity Nb SRF cavities. To better understand the differences between SRF cavities fabricated out of fine-grained polycrystalline sheet in the standard manner and single crystal cavities fabricated by the new technique, two half-cells were produced according to the two different procedures and compared using a variety of analytical techniques including optical microscopy, scanning laser confocal microscopy, profilometry, and X-ray diffraction. Crystallographic orientations, texture, and residual stresses were determined in the samples before and after forming and this poster presents the results of this ongoing study.

  6. Cu2ZnSnS4 absorption layers with controlled phase purity

    PubMed Central

    Su, Chia-Ying; -Yen Chiu, Chiu; Ting, Jyh-Ming

    2015-01-01

    We report the synthesis and characterization of Cu2ZnSnS4 (CZTS) with controlled phase purity. The precursor was first prepared using sequential electrodeposition of Cu, Zn, and Sn in different orders. The Cu/(Sn+Zn) ratio in each stacking order was also varied. The precursor was subjected to annealing at 200°C and sulfurization at 500°C in a 5%-H2S/Ar atmosphere for the formation of CZTS. The phase evolutions during the electrodeposition and annealing stages, and the final phase formation at the sulfurization stage were examined using both x-ray diffractometry and Raman spectroscopy, both of which are shown to be complimentary tools for phase identification. Detailed growth path is therefore reported. We also demonstrate by controlling the stacking order and the Cu/(Sn+Zn) ratio, CZTS with a phase purity as high as 93% is obtained. PMID:25801219

  7. Effect of alkaline and autohydrolysis processes on the purity of obtained hemicelluloses from corn stalks.

    PubMed

    Egüés, Itziar; Sanchez, Cristina; Mondragon, Iñaki; Labidi, Jalel

    2012-01-01

    A study of the potential of autohydrolysis and alkaline extraction processes from corn stalks was performed for high purity hemicellulose extraction. The influence of process parameters on the purity of obtained hemicelluloses was analyzed. An experimental design was developed for the autohydrolysis treatments to determine the optimal conditions to solubilize the hemicelluloses with lowest content in contaminants. On the other hand, alkaline extraction, including raw material pretreatment (dewaxing and delignification step) was carried out analyzing the effectiveness of this processes for maximum pure hemicellulose recovery. The maximum yield (54% of the raw material hemicelluloses) and the best physicochemical properties (highest hemicellulose content free of lignin) were obtained with these pretreatments in alkaline extraction. Moreover, the effect of lignin removal by sulfuric acid from the autohydrolysis liquors before hemicellulose precipitation was studied. This purification step has allowed to obtain lignin-free autohydrolysis hemicellulose but with the presence of sulfur as predominant contaminant. Copyright © 2011 Elsevier Ltd. All rights reserved.

  8. Radiolabelling, quality control and radiochemical purity assessment of the Octreotide analogue 68Ga DOTA NOC.

    PubMed

    Di Pierro, D; Rizzello, A; Cicoria, G; Lodi, F; Marengo, M; Pancaldi, D; Trespidi, S; Boschi, S

    2008-08-01

    Somatostatin receptors 1-5 are over expressed in neuroendocrine tumours (NETs). 68Ga-labelled [1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid]-1-Nal3-Octreotide (DOTA NOC), a recent synthesized somatostatin analogue, shows high affinity for those receptors. Herein, modifications of a commercial module for the labelling of DOTA NOC with 68Ga, as well as the assessment of time course of the radiochemical purity variation are described. The evaluation of radiochemical stability was done by two different chromatographic methods: reversed-phase radio HPLC and fast TLC analysis. Labelled compound has been found radiochemically stable within 3h from the end of labelling (EOL) and radiochemical purity was always higher than 99%. After 73 labelling sessions the system showed great reproducibility and high radiochemical yield.

  9. Characterization of a high-purity germanium detector for small-animal SPECT

    PubMed Central

    Johnson, Lindsay C; Campbell, Desmond L; Hull, Ethan L; Peterson, Todd E

    2011-01-01

    We present an initial evaluation of a mechanically-cooled, high-purity germanium double-sided strip detector as a potential gamma camera for small-animal SPECT. It is 90 mm in diameter and 10 mm thick with two sets of 16 orthogonal strips that have a 4.5 mm width with a 5 mm pitch. We found an energy resolution of 0.96% at 140 keV, an intrinsic efficiency of 43.3% at 122 keV and a FWHM spatial resolution of approximately 1.5 mm. We demonstrated depth-of-interaction estimation capability through comparison of pinhole acquisitions with a point source on and off axis. Finally, a flood-corrected-flood image exhibited a strip-level uniformity of less than 1%. This high-purity germanium offers many desirable properties for small-animal SPECT. PMID:21852723

  10. Out-of-time-ordered correlators and purity in rational conformal field theories

    NASA Astrophysics Data System (ADS)

    Caputa, Paweł; Numasawa, Tokiro; Veliz-Osorio, Alvaro

    2016-11-01

    In this paper we investigate measures of chaos and entanglement in rational conformal field theories in 1 + 1 dimensions. First, we derive a formula for the late time value of the out-of-time-ordered correlators for this class of theories. Our universal result can be expressed as a particular combination of the modular S-matrix elements known as anyon monodromy scalar. Next, in the explicit setup of an SUN Wess-Zumino-Witten model, we compare the late time behavior of the out-of-time-ordered correlators and the purity. Interestingly, in the large-c limit, the purity grows logarithmically as in holographic theories; in contrast, the out-of-time-ordered correlators remain, in general, nonvanishing.

  11. Aluminum anode for aluminum-air battery - Part I: Influence of aluminum purity

    NASA Astrophysics Data System (ADS)

    Cho, Young-Joo; Park, In-Jun; Lee, Hyeok-Jae; Kim, Jung-Gu

    2015-03-01

    2N5 commercial grade aluminum (99.5% purity) leads to the lower aluminum-air battery performances than 4N high pure grade aluminum (99.99% purity) due to impurities itself and formed impurity complex layer which contained Fe, Si, Cu and others. The impurity complex layer of 2N5 grade Al declines the battery voltage on standby status. It also depletes discharge current and battery efficiency at 1.0 V which is general operating voltage of aluminum-air battery. However, the impurity complex layer of 2N5 grade Al is dissolved with decreasing discharge voltage to 0.8 V. This phenomenon leads to improvement of discharge current density and battery efficiency by reducing self-corrosion reaction. This study demonstrates the possibility of use of 2N5 grade Al which is cheaper than 4N grade Al as the anode for aluminum-air battery.

  12. Diels-Alder reactions as an efficient route to high purity cyclic polymers.

    PubMed

    Glassner, Mathias; Blinco, James P; Barner-Kowollik, Christopher

    2011-05-18

    A simple and efficient route for the synthesis of cyclic polymer systems is presented. Linear furan protected α-maleimide-ω-cyclopentadienyl functionalized precursors (poly(methyl methacrylate) and poly(tert-butyl acrylate)) were synthesized via atom transfer radical polymerization (ATRP) and subsequent substitution of the bromine end-group with cyclopentadiene. Upon heating at high dilution, deprotection of the dieneophile occurs followed by an intramolecular Diels-Alder reaction yielding a high purity cyclic product.

  13. Note: Simple and portable setup for loading high purity liquids in diamond anvil cell.

    PubMed

    Olejnik, Ella; Deemyad, Shanti

    2016-03-01

    Here we explain a simple and inexpensive procedure to preserve the original purity of the liquid samples during the loading process in a diamond anvil cell. The idea is to keep the sample in frozen form during the loading process while preventing the condensation of the water or other introduction of contaminants. The system can be quickly and easily assembled in a basic laboratory setup. This process can be used for loading some of the common pressure media in a diamond anvil cell.

  14. [Rapid and nondestructive discrimination of hybrid maize seed purity using near infrared spectroscopy].

    PubMed

    Huang, Yan-yan; Zhu, Li-wei; Li, Jun-hui; Wang, Jian-hua; Sun, Bao-qi; Sun, Qun

    2011-03-01

    Near infrared spectroscopy technology was applied to study rapid and nondestructive discrimination method of hybrid maize seed purity. With NongDa108 hybrid seeds and mother 178 seeds, a discrimination model for the purity of maize single seed was built by near infrared reflectance spectroscopy with distinguished partial least squares (DPLS). A total of 200 seeds including 100 hybrid seeds and 100 mother seeds were divided into two groups: calibration set (150 samples) and validation set (50 samples), and each group had same number of hybrid and mother seeds. To eliminate human errors as much as possible we used two sample cups with transmission hole diameter of 3.0 and 4.5 mm, respectively, at the bottom for spectrum acquisition. The location of sample cups and seeds were fixed during spectrum acquisition process. The result showed that the average identification rate with 3 mm transmission hole diameter was 99.82%, significantly higher than that of 4.5 mm whose average identification rate was just 90.96%. There was no significant difference among the identification rates of one replicate and two replicates spectrum on endosperm face, two replicates spectrum on embryo face and four replicates. The rates of validation set reached about 99%, slightly more than that of one replicate on embryo face. The identification rates of one spectrum and two replicates spectrum on endosperm face in calibration and validation set were 100%, with the spectral region between 4000 and 8000 cm(-1). With 3.0 mm transmission hole diameter and 4000-8000 cm(-1) spectral region, the seed purity identification rates in calibration and validation sets built up by one spectrum on endosperm face were 100%. With the increase in principal components, the identification rates in calibration set and validation set gradually increased, and when principal components reached 9, the rate in both of sets were 100%. The results have important value for rapid and nondestructive testing of hybrid maize

  15. Determinants of heroin retail prices in metropolitan France: Discounts, purity and local markets.

    PubMed

    Lahaie, Emmanuel; Janssen, Eric; Cadet-Taïrou, Agnès

    2016-09-01

    Field studies have indicated a recent increase in heroin availability and use in France, and yet very little is known about the mechanisms underlying heroin retail prices. This paper offers a first attempt at identifying the determinants of heroin pricing, to measure quantity discounts and assess the influence of purity on street prices, while controlling for a geographical effect. Data on heroin samples were collected during 2011 in seven urban areas of metropolitan France. Ordinary least squares regression was used to model the associations between price, quantity, purity and other independent variables. Quantity remains the most influential variable on heroin pricing. We estimate that a 10% increase in the size of a transaction leads to a 2.3% decrease in the unit price. Assessed purity proved to be significant, although in modest proportion. Sociodemographic characteristics, such as gender, users' experience and relationships with dealers, proved to be insignificant. Heroin retail prices vary according to a geographical gradient related to the routes of entry and distribution. As a credence good, heroin retail prices in France are affected by more than simply the traditional supply and demand relationship. The results of this study also underline the limitations of a quantitative framework and should be complemented by further ethnographic research to obtain an in-depth understanding of local markets. Policies should be designed to better take local disparities into account.[Lahaie E, Janssen E, Cadet-Taïrou A. Determinants of heroin retail prices in metropolitan France:Discounts, purity and local markets. Drug Alcohol Rev 2016;35:597-604]. © 2015 Australasian Professional Society on Alcohol and other Drugs.

  16. In vitro characterization of high purity factor IX concentrates for the treatment of hemophilia B.

    PubMed

    Limentani, S A; Gowell, K P; Deitcher, S R

    1995-04-01

    This study employed sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis and immunoblotting to assess the purity of seven high purity factor IX concentrates: Aimafix (Aima), AlphaNine-SD (Alpha Therapeutic), Factor IX VHP (Biotransfusion), Immunine (Immuno), Mononine (Armour Pharmaceutical), Nanotiv (Kabi Pharmacia), and 9MC (Blood Products Laboratory). The mean specific activity of these products ranged from 68 U factor IX/mg (Aimafix) to 246 U factor IX/mg (Mononine). SDS-PAGE analysis showed that the highest purity product, Mononine, had a single contaminating band under non-reducing conditions. Two additional bands were detected when this product was analyzed under reducing conditions. All other products had multiple contaminating bands that were more apparent under reducing than non-reducing conditions. The immunoblot for factor IX showed a dominant factor IX band for all products. In addition, visible light chain of factor IX was detected for AlphaNine-SD, Factor IX VHP, Immunine, Mononine, Nanotiv, and 9MC, suggesting that the factor IX in these products had undergone partial activation to factor IXa. Another contaminating band was visible at 49,500 for all of the products except 9MC. In addition to this band, high molecular weight contaminants were apparent for some products, most notably AlphaNine-SD. The identity of these bands is unknown. Immunoblotting failed to demonstrate factor VII as a contaminant of any of the high purity products, although factor VIIa could be detected in some lots of Immunine, Nanotiv, and 9MC by a clot-based assay. Factor X contaminated Aimafix, AlphaNine-SD, Factor IX VHP, Immunine, Nanotiv, and 9MC, but activation products of factor X were not detected.(ABSTRACT TRUNCATED AT 250 WORDS)

  17. High Purity Americium-241 for Fuel Cycle R&D Program

    SciTech Connect

    Dr. Paul A. Lessing

    2011-07-01

    Previously the U.S. Department of Energy released Am-241 for various applications such as smoke detectors and Am-Be neutron sources for oil wells. At this date there is a shortage of usable, higher purity Am-241 in metal and oxide form available in the United States. Recently, the limited source of Am-241 has been from Russia with production being contracted to existing customers. The shortage has resulted in the price per gram rising dramatically over the last few years. DOE-NE currently has need for high purity Am-241 metal and oxide to fabricate fuel pellets for reactor testing in the Fuel Cycle R&D program. All the available high purity americium has been gathered from within the DOE system of laboratories. However, this is only a fraction of the projected needs of FCRD over the next 10 years. Therefore, FCR&D has proposed extraction and purification concepts to extract Am-241 from a mixed AmO2-PuO2 feedstock stored at the Savannah River Site. The most simple extraction system is based upon high temperature reduction using lanthanum metal with concurrent evaporation and condensation to produce high purity Am metal. Metallic americium has over a four order of magnitude higher vapor pressure than plutonium. Results from small-scale reduction experiments are presented. These results confirm thermodynamic predictions that at 1000 deg C metallic lanthanum reduces both PuO2 and AmO2. Faster kinetics are expected for temperatures up to about 1500 deg C.

  18. Aluminium. II - A review of deformation properties of high purity aluminium and dilute aluminium alloys.

    NASA Technical Reports Server (NTRS)

    Reed, R. P.

    1972-01-01

    The elastic and plastic deformation behavior of high-purity aluminum and of dilute aluminum alloys is reviewed. Reliable property data, including elastic moduli, elastic coefficients, tensile, creep, fatigue, hardness, and impact are presented. Single crystal tensile results are discussed. Rather comprehensive reference lists, containing publications of the past 20 years, are included for each of the above categories. Defect structures and mechanisms responsible for mechanical behavior are presented. Strengthening techniques (alloys, cold work, irradiation, quenching, composites) and recovery are briefly reviewed.

  19. Note: Simple and portable setup for loading high purity liquids in diamond anvil cell

    NASA Astrophysics Data System (ADS)

    Olejnik, Ella; Deemyad, Shanti

    2016-03-01

    Here we explain a simple and inexpensive procedure to preserve the original purity of the liquid samples during the loading process in a diamond anvil cell. The idea is to keep the sample in frozen form during the loading process while preventing the condensation of the water or other introduction of contaminants. The system can be quickly and easily assembled in a basic laboratory setup. This process can be used for loading some of the common pressure media in a diamond anvil cell.

  20. Effective vortex mass from microscopic theory

    NASA Astrophysics Data System (ADS)

    Han, Jung Hoon; Kim, June Seo; Kim, Min Jae; Ao, Ping

    2005-03-01

    We calculate the effective mass of a single quantized vortex in the Bardeen-Cooper-Schrieffer superconductor at finite temperature. Based on effective action approach, we arrive at the effective mass of a vortex as integral of the spectral function J(ω) divided by ω3 over frequency. The spectral function is given in terms of the quantum-mechanical transition elements of the gradient of the Hamiltonian between two Bogoliubov-deGennes (BdG) eigenstates. Based on self-consistent numerical diagonalization of the BdG equation we find that the effective mass per unit length of vortex at zero temperature is of order m(kfξ0)2 ( kf=Fermi momentum, ξ0=coherence length), essentially equaling the electron mass displaced within the coherence length from the vortex core. Transitions between the core states are responsible for most of the mass. The mass reaches a maximum value at T≈0.5Tc and decreases continuously to zero at Tc .

  1. PINGU sensitivity to neutrino mass hierarchy

    SciTech Connect

    Groß, Andreas; Collaboration: IceCube-PINGU Collaboration

    2014-11-18

    Determination of the neutrino mass hierarchy (NMH) is among the most fundamental questions in particle physics. Recent measurements of 1) a large mixing angle between the first and the third neutrino mass eigenstates and 2) the first observation of atmospheric neutrino oscillations at tens of GeV with neutrino telescopes, open the intriguing new possibility to exploit matter effects in neutrino oscillation to determine the neutrino mass hierarchy. A further extension of IceCube/DeepCore called PINGU (Precision IceCube Next Generation Upgrade) has been recently envisioned with the ultimate goal to measure neutrino mass hierarchy. PINGU would consist of additional IceCube-like strings of detectors deployed in the deepest and cleanest ice in the center of IceCube. More densely deployed instrumentation would provide a threshold substantially below 10 GeV and enhance the sensitivity to the mass hierarchy signal in atmospheric neutrinos. Here we discuss an estimate of the PINGU sensitivity to the mass hierarchy determined using an approximation with an Asimov dataset and an oscillation parameter fit.

  2. Geometric representation of fundamental particles' inertial mass

    SciTech Connect

    Schachter, L.; Spencer, James

    2015-07-22

    A geometric representation of the (N = 279) masses of quarks, leptons, hadrons and gauge bosons was introduced by employing a Riemann Sphere facilitating the interpretation of the N masses in terms of a single particle, the Masson, which might be in one of the N eigen-states. Geometrically, its mass is the radius of the Riemann Sphere. Dynamically, its derived mass is near the mass of the nucleon regardless of whether it is determined from all N particles of only the hadrons, the mesons or the baryons separately. Ignoring all the other properties of these particles, it is shown that the eigen-values, the polar representation θν of the masses on the Sphere, satisfy the symmetry θν + θN+1-ν = π within less than 1% relative error. In addition, these pair correlations include the pairs θγ + θtop ≃ π and θgluon + θH ≃ π as well as pairing the weak gauge bosons with the three neutrinos.

  3. Determination of indium in high purity antimony by electrothermal atomic absorption spectrometry (ETAAS) using boric acid as a modifier.

    PubMed

    Dash, K; Thangavel, S; Chaurasia, S C; Arunachalam, J

    2006-10-15

    The use of boric acid as a modifier for the determination of trace amount of indium in high purity antimony by electrothermal atomic absorption is described. It was found that the negative influence of the hydrofluoric acid, used for the digestion could not be eliminated by using stabilized temperature platform furnace (STPF) alone. Due to the high dissociation energy (D(0)=506kJmol(-1)) of indium fluoride, it is difficult to dissociate in the gas phase and hence is lost. In presence of HF (used for the dissolution of antimony), the universal Pd-Mg modifier does not work satisfactorily. Additionally, rising corrosion and reduced tube lifetime were observed when the acid digested (HF-HNO(3)) antimony solution was injected in to the platform. Improvement in platform life and elimination of interferences were achieved by the addition of boric acid as a chemical modifier together with ruthenium coating of the platform. Corrosive changes of the transversely heated graphite atomizer (THGA) platform surface were examined by scanning electron microscopy. The standard addition method was applied. A characteristic mass of 36pg was obtained. The detection limit of the proposed method is around 0.04mugg(-1). The developed method was applied to the determination of indium in real samples. The data obtained by this method were in good agreement with those obtained by ICP-MS.

  4. Electrophoretic Behavior of Anionic Triazine and PAMAM Dendrimers: Methods for Improving Resolution and Assessing Purity Using Capillary Electrophoresis

    PubMed Central

    Lalwani, Sanjiv; Venditto, Vincent J.; Chouai, Abdellatif; Rivera, Gregory E.; Shaunak, Sunil; Simanek, Eric E.

    2009-01-01

    The synthesis and characterization of second- and third-generation triazine dendrimers bearing carboxylic acid groups on the periphery are reported. These materials were synthesized by exhaustive succinylation of amine-terminated dendrimers. 1H and 13C NMR spectra are consistent with the desired products, but these techniques are limited by degeneracy in signals. MALDI-TOF mass spectrometry confirms the presence of the desired material. These materials display pH-dependent solubility in water. Capillary electrophoresis proves to be valuable in multiple elements of this work, and general protocols emerge that appear to be useful for the characterization of lower-generation anionic dendrimers. Specifically, capillary electrophoresis provides a convenient method for monitoring the removal of excess succinic anhydride/succinic acid and offers additional clues to the chemical nature of the impurities in these samples. Optimization of the background electrolyte and instrumental parameters allows for the assessment of the purity of these triazine targets as well as comparison with two sets of commercially available anionic poly(amidoamine) (PAMAM) dendrimers. Corroborative information from the different orthogonal analytical techniques employed supports the hypothesis that triazine dendrimers exist as very narrowly disperse mixtures of macromolecules approaching, in some cases, single chemical entities. PMID:20725528

  5. Influence of microstructural purity on the bending fatigue behavior of VAR-melted superelastic Nitinol.

    PubMed

    Launey, Maximilien; Robertson, Scott W; Vien, Lot; Senthilnathan, Karthikeyan; Chintapalli, Prashanth; Pelton, Alan R

    2014-06-01

    The bending fatigue resistance of commercially-available Standard versus High Purity Nitinol was evaluated at 3% mean strain and a range of strain amplitudes with the simple wire Z-specimen geometry. The Standard grade Nitinol demonstrated a 10(7)-cycle fatigue strain limit of 0.50% alternating strain, comparable to results reported elsewhere in the literature. Conversely, the High Purity grade VAR Nitinol demonstrated a 5-fold improvement in fatigue resistance with an impressive 10(7)-cycle fatigue strain limit of 2.5% alternating strain. The High Purity Nitinol has an oxygen+nitrogen content of 60wppm, maximum wrought-material inclusion length of 17µm, and inclusion volume fraction of 0.28%, all substantially less than industry standards. With all processing variables held constant except for inclusion content, it is clear that this marked fatigue superiority is due exclusively to the reduction in both size and area fraction of inclusions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Ehrenfest dynamics is purity non-preserving: A necessary ingredient for decoherence

    NASA Astrophysics Data System (ADS)

    Alonso, J. L.; Clemente-Gallardo, J.; Cuchí, J. C.; Echenique, P.; Falceto, F.

    2012-08-01

    We discuss the evolution of purity in mixed quantum/classical approaches to electronic nonadiabatic dynamics in the context of the Ehrenfest model. As it is impossible to exactly determine initial conditions for a realistic system, we choose to work in the statistical Ehrenfest formalism that we introduced in Alonso et al. [J. Phys. A: Math. Theor. 44, 396004 (2011), 10.1088/1751-8113/44/39/395004]. From it, we develop a new framework to determine exactly the change in the purity of the quantum subsystem along with the evolution of a statistical Ehrenfest system. In a simple case, we verify how and to which extent Ehrenfest statistical dynamics makes a system with more than one classical trajectory, and an initial quantum pure state become a quantum mixed one. We prove this numerically showing how the evolution of purity depends on time, on the dimension of the quantum state space D, and on the number of classical trajectories N of the initial distribution. The results in this work open new perspectives for studying decoherence with Ehrenfest dynamics.

  7. Focused electron beam induced deposition of copper with high resolution and purity from aqueous solutions

    NASA Astrophysics Data System (ADS)

    Esfandiarpour, Samaneh; Boehme, Lindsay; Hastings, J. Todd

    2017-03-01

    Electron-beam induced deposition of high-purity copper nanostructures is desirable for nanoscale rapid prototyping, interconnection of chemically synthesized structures, and integrated circuit editing. However, metalorganic, gas-phase precursors for copper introduce high levels of carbon contamination. Here we demonstrate electron beam induced deposition of high-purity copper nanostructures from aqueous solutions of copper sulfate. The addition of sulfuric acid eliminates oxygen contamination from the deposit and produces a deposit with ∼95 at% copper. The addition of sodium dodecyl sulfate (SDS), Triton X-100, or polyethylene glycole (PEG) improves pattern resolution and controls deposit morphology but leads to slightly reduced purity. High resolution nested lines with a 100 nm pitch are obtained from CuSO4–H2SO4–SDS–H2O. Higher aspect ratios (∼1:1) with reduced line edge roughness and unintended deposition are obtained from CuSO4–H2SO4–PEG–H2O. Evidence for radiation-chemical deposition mechanisms was observed, including deposition efficiency as high as 1.4 primary electrons/Cu atom.

  8. The effect of foil purity on morphology of anodized nanoporous ZrO2

    NASA Astrophysics Data System (ADS)

    Wierzbicka, Ewa; Syrek, Karolina; Sulka, Grzegorz D.; Pisarek, Marcin; Janik-Czachor, Maria

    2016-12-01

    A two-step electrochemical formation of nanoporous zirconium oxide layers on different zirconium foils (purity 99.2% and 99.8%) was investigated. Anodizations were carried out at 20 V in an electrolyte composed of 1 M (NH4)2SO4 and 0.15 M NH4F. It was found that the thickness of grown oxide layer, and consequently, the rate of oxide formation depend slightly on the Zr substrate purity. The pore nucleation and anodization process occur easier in the presence of higher concentration of impurities. From top view SEM images, the structural parameters of oxide layers such as pore diameter, interpore distance, pore density, wall thickness and porosity of anodic oxide layers were estimated for both types of used substrates. On the other hand, cell size, intercell distance and cell density were evaluated from the bottom side of anodic oxide layers. A special emphasis was put on the qualitative analysis of hexagonal arrangement of nanopores and cells. The nanopore and cells arrangements in formed oxides were evaluated using various approaches based on Delaunay triangulations, angular distribution functions (ADFs) and pair distribution functions (PDFs). These results were supported by calculations of percentage of defective pores and cells for both types of used Zr substrates. The use of low purity Zr for anodizing does not affect drastically the morphology of formed nanoporous zirconia and offers a promising perspective to reduce production costs and increase availability of this material.

  9. Increased recovery and improved purity of PHA from recombinant Cupriavidus necator

    PubMed Central

    Anis, Siti Nor Syairah; Iqbal, Nurhezreen Md; Kumar, Sudesh; Al-Ashraf, Amirul

    2013-01-01

    A simple procedure for recovering biodegradable polymer from bacterial cells has been developed using economical and environmentally friendly solvent or chemicals. Recombinant bacterium, Cupriavidus necator harboring pBBR1MCS-C2 plasmid polyhydroxyalkanoate (PHA) synthase gene was used for the production of copolymer P(3HB-co-3HHx) from crude palm kernel oil (CPKO). NaOH was chosen in this study as it could give high purity and recovery yield. Increase of NaOH concentration had resulted in an increase of the PHA purity, but the recovery yield had decreased. The greater improvement of PHA purity and recovery were achieved by incubating the freeze-dried cells (10–30 g/L) in NaOH (0.1 M) for 1–3 h at 30°C and polishing using 20% (v/v) of ethanol. The treatment caused negligible degradation of the molecular weight of PHA recovered from the bacterial cells. The present review also highlights other extraction methods to provide greater insights into economical and sustainable recovery of PHA from bacterial cells. PMID:23018620

  10. Focused electron beam induced deposition of copper with high resolution and purity from aqueous solutions.

    PubMed

    Esfandiarpour, Samaneh; Boehme, Lindsay; Hastings, J Todd

    2017-03-24

    Electron-beam induced deposition of high-purity copper nanostructures is desirable for nanoscale rapid prototyping, interconnection of chemically synthesized structures, and integrated circuit editing. However, metalorganic, gas-phase precursors for copper introduce high levels of carbon contamination. Here we demonstrate electron beam induced deposition of high-purity copper nanostructures from aqueous solutions of copper sulfate. The addition of sulfuric acid eliminates oxygen contamination from the deposit and produces a deposit with ∼95 at% copper. The addition of sodium dodecyl sulfate (SDS), Triton X-100, or polyethylene glycole (PEG) improves pattern resolution and controls deposit morphology but leads to slightly reduced purity. High resolution nested lines with a 100 nm pitch are obtained from CuSO4-H2SO4-SDS-H2O. Higher aspect ratios (∼1:1) with reduced line edge roughness and unintended deposition are obtained from CuSO4-H2SO4-PEG-H2O. Evidence for radiation-chemical deposition mechanisms was observed, including deposition efficiency as high as 1.4 primary electrons/Cu atom.

  11. Increased recovery and improved purity of PHA from recombinant Cupriavidus necator.

    PubMed

    Anis, Siti Nor Syairah; Iqbal, Nurhezreen Md; Kumar, Sudesh; Al-Ashraf, Amirul

    2013-01-01

    A simple procedure for recovering biodegradable polymer from bacterial cells has been developed using economical and environmentally friendly solvent or chemicals. Recombinant bacterium, Cupriavidus necator harboring pBBR1MCS-C2 plasmid polyhydroxyalkanoate (PHA) synthase gene was used for the production of copolymer P(3HB-co-3HHx) from crude palm kernel oil (CPKO). NaOH was chosen in this study as it could give high purity and recovery yield. Increase of NaOH concentration had resulted in an increase of the PHA purity, but the recovery yield had decreased. The greater improvement of PHA purity and recovery were achieved by incubating the freeze-dried cells (10-30 g/L) in NaOH (0.1 M) for 1-3 h at 30°C and polishing using 20% (v/v) of ethanol. The treatment caused negligible degradation of the molecular weight of PHA recovered from the bacterial cells. The present review also highlights other extraction methods to provide greater insights into economical and sustainable recovery of PHA from bacterial cells.

  12. Anodic nanotubular/porous hematite photoanode for solar water splitting: substantial effect of iron substrate purity.

    PubMed

    Lee, Chong-Yong; Wang, Lei; Kado, Yuya; Killian, Manuela S; Schmuki, Patrik

    2014-03-01

    Anodization of iron substrates is one of the most simple and effective ways to fabricate nanotubular (and porous) structures that could be directly used as a photoanode for solar water splitting. Up to now, all studies in this field focused on achieving a better geometry of the hematite nanostructures for a higher efficiency. The present study, however, highlights that the purity of the iron substrate used for any anodic-hematite-formation approach is extremely important in view of the water-splitting performance. Herein, anodic self-organized oxide morphologies (nanotubular and nanoporous) are grown on different iron substrates under a range of anodization conditions, including elevated temperatures and anodization supported by ultrasonication. Substrate purity has not only a significant effect on oxide-layer growth rate and tube morphology, but also gives rise to a ninefold increase in the photoelectrochemical water-splitting performance (0.250 vs. 0.028 mA cm−2 at 1.40 V vs. reversible hydrogen electrode under AM 1.5 100 mW cm−2 illumination) for 99.99 % versus 99.5 % purity iron substrates of similar oxide geometry. Elemental analysis and model alloys show that particularly manganese impurities have a strong detrimental effect on the water-splitting performance.

  13. Combined ultrafiltration-electrodeionization technique for production of high purity water.

    PubMed

    Wardani, Anita Kusuma; Hakim, Ahmad Nurul; Khoiruddin; Wenten, I Gede

    2017-06-01

    Electrodeionization (EDI) is the most common method to produce high purity water used for boiler feed water, microelectronic, and pharmaceutical industries. Commonly, EDI is combined with reverse osmosis (RO) to meet the requirement of EDI feed water, with hardness less than 1 ppm. However, RO requires a relatively high operating pressure and ultrafiltration (UF) as pretreatment which results in high energy consumption and high complexity in piping and instrumentation. In this work, UF was used as the sole pretreatment of EDI to produce high purity water. Tap water with conductivity 248 μS/cm was fed to UF-EDI system. The UF-EDI system showed good performance with ion removal more than 99.4% and produced water with low conductivity from 0.2 to 1 μS/cm and total organic compounds less than 0.3 ppm. Generally, product conductivity decreased with the increase of current density of EDI and the decrease of feed velocity and UF pressure. The energy consumption for UF-EDI system in this work was 0.89-2.36 kWh/m(3). These results proved that UF-EDI system meets the standards of high purity water for pharmaceutical and boiler feed water with lower investment and energy consumption than RO-EDI system.

  14. A novel process for the production of high-purity galactooligosaccharides (GOS) using consortium of microbes.

    PubMed

    Saravanan, R; Shubethar, Shajahan; Narayanan, S; Jain, Manish; Lade, Shankar; Jadhav, Deepak; Maheswaran, P; Avalakki, Uday K; Dubey, Ashok Kumar

    2017-03-16

    Galactooligosaccharides (GOS) are nondigestible dietary fibers which have a beneficial effect on human health by promoting the growth of probiotic bacteria in the gut. In addition, other health benefits have been reported from oligosaccharides consumption such as stimulation of intestinal mobility, colon cancer prevention, mineral absorption as well as protection against certain pathogenic bacterial infections. The goal of this research was to develop an efficient biotransformation system using a consortium of microbes for the production of ≥85% pure GOS and reusing the cell biomass in repeated cycles of biotransformation. Production of GOS by lactose transgalactosylation using whole cells of Sporobolomyces singularis MTCC 5491 as a source of β-galactosidase and monosaccharides utilization by yeast isolate (NUTIDY007) were studied. For increasing the purity of GOS, growth and bioconversion parameters on the transgalactosylation by the whole cells were investigated. Further, continuous production of GOS was studied in a reactor with microfiltration membrane system. A maximum GOS purity of 42% was achieved using single culture of S. singularis. Under optimized conditions, single culture of S. singularis produced a maximum of 56% pure GOS. Addition of second culture to the reaction mixture for utilization of glucose significantly increased the GOS purity from 56% to ≥85%. The product consisted of tri- to penta-galactooligosaccharides. Trisaccharides were the main component of the reaction mixture. A maximum productivity of 10.9 g/L/hr was obtained under the optimum conditions.

  15. Ehrenfest dynamics is purity non-preserving: A necessary ingredient for decoherence

    SciTech Connect

    Alonso, J. L.; and others

    2012-08-07

    We discuss the evolution of purity in mixed quantum/classical approaches to electronic nonadiabatic dynamics in the context of the Ehrenfest model. As it is impossible to exactly determine initial conditions for a realistic system, we choose to work in the statistical Ehrenfest formalism that we introduced in Alonso et al. [J. Phys. A: Math. Theor. 44, 396004 (2011)]. From it, we develop a new framework to determine exactly the change in the purity of the quantum subsystem along with the evolution of a statistical Ehrenfest system. In a simple case, we verify how and to which extent Ehrenfest statistical dynamics makes a system with more than one classical trajectory, and an initial quantum pure state become a quantum mixed one. We prove this numerically showing how the evolution of purity depends on time, on the dimension of the quantum state space D, and on the number of classical trajectories N of the initial distribution. The results in this work open new perspectives for studying decoherence with Ehrenfest dynamics.

  16. Purity and decoherence in the theory of a damped harmonic oscillator.

    PubMed

    Isar, A; Sandulescu, A; Scheid, W

    1999-12-01

    For the generalized master equations derived by Karrlein and Grabert for the microscopic model of a damped harmonic oscillator, the conditions for purity of states are written, in particular for different initial conditions and different types of damping, including Ohmic, Drude, and weak coupling cases, and the Agarwal and Weidlich-Haake models. It is shown that the states which remain pure are the squeezed states with variances that are constant in time. For pure states, generalized nonlinear Schrödinger-type equations corresponding to these master equations are also obtained. Then the condition for purity of states of a damped harmonic oscillator is considered in the framework of Lindblad theory for open quantum systems. For a special choice of the environment coefficients, correlated coherent states with constant variances and covariance are shown to be the only states which remain pure all the time during the evolution of the considered system. In Karrlein-Grabert and Lindblad models, as well as in the particular models considered, expressions for the rate of entropy production are written, and it is shown that state which preserve their purity in time are also states which minimize entropy production and, therefore, are the most stable state under evolution in the presence of the environment, and play an important role in the description of decoherence phenomenon.

  17. Purity and decoherence in the theory of a damped harmonic oscillator

    NASA Astrophysics Data System (ADS)

    Isar, A.; Sandulescu, A.; Scheid, W.

    1999-12-01

    For the generalized master equations derived by Karrlein and Grabert for the microscopic model of a damped harmonic oscillator, the conditions for purity of states are written, in particular for different initial conditions and different types of damping, including Ohmic, Drude, and weak coupling cases, and the Agarwal and Weidlich-Haake models. It is shown that the states which remain pure are the squeezed states with variances that are constant in time. For pure states, generalized nonlinear Schrödinger-type equations corresponding to these master equations are also obtained. Then the condition for purity of states of a damped harmonic oscillator is considered in the framework of Lindblad theory for open quantum systems. For a special choice of the environment coefficients, correlated coherent states with constant variances and covariance are shown to be the only states which remain pure all the time during the evolution of the considered system. In Karrlein-Grabert and Lindblad models, as well as in the particular models considered, expressions for the rate of entropy production are written, and it is shown that state which preserve their purity in time are also states which minimize entropy production and, therefore, are the most stable state under evolution in the presence of the environment, and play an important role in the description of decoherence phenomenon.

  18. Synthesis and Characterization of High-Purity Bismuth Nanowires via Seed-Assisted Growth Approach

    NASA Astrophysics Data System (ADS)

    Mu, Xin; Zhao, Wen-Yu; He, Dan-Qi; Zhou, Hong-Yu; Zhu, Wan-Ting; Zhang, Qing-Jie

    2015-06-01

    Nanowires are considered as high-performance thermoelectric materials with large Seebeck coefficients due to quantum confinement and low thermal conductivity because of enhanced boundary scattering of phonons. In this work, a seed-assisted growth method has been developed to synthesize high-purity bismuth nanowires. The bismuth seeds were first synthesized by reducing BiCl3 in the ice water with NaBH4. The high-purity bismuth nanowires about 40-50 nm in diameter and several tens of micrometers in length were then grown on bismuth seeds by reducing NaBiO3 with ethylene glycol. X-ray diffraction, scanning electron microscopy, and transmission electron microscopy were employed to characterize the crystal structure, microstructure, and growth direction of the bismuth seeds and nanowires. The effects of temperature, reductant, and bismuth seeds template on the microstructures of the bismuth nanowires were also investigated. The synthesis conditions of bismuth seeds and nanowires were optimized. The selected area electron diffraction pattern confirms that the growth direction of bismuth nanowires is parallel to [] direction. It was discovered that high-purity bismuth nanowires with high aspect ratio can be synthesized by precisely controlling the temperature to adjust the nucleation rate of the bismuth nuclei, selecting the appropriate reductant to maintain a low nucleation rate, and using bismuth seeds as the template of the epitaxial growth of the bismuth nuclei.

  19. Production of extreme-purity aluminum and silicon by fractional crystallization processing

    NASA Astrophysics Data System (ADS)

    Dawless, R. K.; Troup, R. L.; Meier, D. L.; Rohatgi, A.

    1988-06-01

    Large scale fractional crystallization is used commercially at Alcoa to produce extreme purity aluminum (99.999+% Al). The primary market is sputtering targets used to make interconnects for integrated circuits. For some applications the impurities uranium and thorium are reduced to less than 1 ppbw to avoid "soft errors" associated with α particle emission. The crystallization process achieves segregation coefficients which are close to theoretical at normal yields, and this, coupled with the scale of the units, allows practical production of this material. The silicon purification process involves crystallization of Si from molten aluminum alloys containing about 30% silicon. The crystallites from this process are further treated to remove residual Al and an extreme purity ingot is obtained. This material is considered suitable for single crystal or ribbon type photovoltaic cells and for certain IC applications, including highly doped substrates used for epitaxial growth. In production of both extreme purity Al and Si, impurities are rejected to the remaining melt as the crystals form and some separation is achieved by draining this downgraded melt from the unit. Purification of this downgrade by crystallization has also been demonstrated for both systems and is important for achieving high recoveries.

  20. Capillary gel electrophoresis for the quantification and purity determination of recombinant proteins in inclusion bodies.

    PubMed

    Espinosa-de la Garza, Carlos E; Perdomo-Abúndez, Francisco C; Campos-García, Víctor R; Pérez, Néstor O; Flores-Ortiz, Luis F; Medina-Rivero, Emilio

    2013-09-01

    In this work, a high-resolution CGE method for quantification and purity determination of recombinant proteins was developed, involving a single-component inclusion bodies (IBs) solubilization solution. Different recombinant proteins expressed as IBs were used to show method capabilities, using recombinant interferon-β 1b as the model protein for method validation. Method linearity was verified in the range from 0.05 to 0.40 mg/mL and a determination coefficient (r(2) ) of 0.99 was obtained. The LOQs and LODs were 0.018 and 0.006 mg/mL, respectively. RSD for protein content repeatability test was 2.29%. In addition, RSD for protein purity repeatability test was 4.24%. Method accuracy was higher than 90%. Specificity was confirmed, as the method was able to separate recombinant interferon-β 1b monomer from other aggregates and impurities. Sample content and purity was demonstrated to be stable for up to 48 h. Overall, this method is suitable for the analysis of recombinant proteins in IBs according to the attributes established on the International Conference for Harmonization guidelines.

  1. Synthesis and Characterization of High-Purity Tellurium Nanowires via Self-seed-Assisted Growth Approach

    NASA Astrophysics Data System (ADS)

    Li, Ying; Zhao, Wen-yu; Mu, Xin; Liu, Xing; He, Dan-qi; Zhu, Wan-ting; Zhang, Qing-jie

    2016-03-01

    Nanowires have attracted intense attention in recent years due to their novel physical properties. In this work, we prepare high-purity tellurium nanowires through the self-seed-assisted growth method previously developed by us. The tellurium seeds were firstly synthesized by reducing Na2TeO3 in the ice water with NaBH4. The high-purity tellurium nanowires with a diameter of 40-50 nm and a length of several tens of micrometers were then grown on tellurium seeds by reducing Na2TeO3 with hydrazine hydrate. X-ray diffraction, scanning electron microscopy and transmission electron microscopy were employed to characterize the crystal structure, microstructure, and growth direction of tellurium seeds and nanowires. The effects of temperature, time, surfactant and tellurium seeds on microstructures of tellurium nanowires has also been investigated. The synthesis conditions of tellurium seeds and nanowires was optimized. The selected area electron diffraction pattern confirms that the growth direction of tellurium nanowires is parallel to [0001] direction. It was discovered that high-purity tellurium nanowires with high aspect ratio can be synthesized by precisely controlling the temperature to adjust the nucleation rate of the tellurium nuclei, selecting the appropriate surfactant to induce the coordination along the macromolecular chain, and using tellurium seeds as the templates of the epitaxial growth of tellurium nuclei.

  2. Determination of trace metallic impurities in high-purity quartz by ion chromatography.

    PubMed

    Dash, K; Chandrasekaran, K; Thangavel, S; Dhaville, S M; Arunachalam, J

    2004-01-02

    A method has been developed for the determination of relevant trace impurities (alkali, alkaline and transition metals) in high purity quartz by ion-chromatography. In situ reagent (HF) purification and simultaneous sample dissolution was achieved in a multichannel vapour phase digestion assembly. Twenty-one samples can be digested at a time in this vapour phase system. Significant decrease in the process blank levels for all the analytes was observed. Drastic reduction (250 times) of NH4+ blank was achieved in the described vapour phase digestion, which enables the determination of trace concentration of sodium in high purity quartz. After volatilisation of the matrix and unreacted HF, the clear water leached solutions were injected into an ion-chromatograph equipped with conductivity detector for the determination of alkali and alkaline earth metals. In the case of transition metals, the trace residues were leached with 10 mM HCl and after separation on a mixed bed analytical column (IonPac CS5) were detected by spectrophotometry after post column derivatisation using 4-(2-pyridylazo)resorcinol (PAR). The accuracy of the result was checked by their comparison with those obtained by independent methods like inductively coupled plasma (ICP) MS and ICP atomic emission spectrometry. The achievable detection limits are between 0.4 ng/g (Li) and 22 ng/g (Mn). The application of the method to the determination of the above trace metals in two high-purity-grade quartz samples is demonstrated.

  3. High-purity propionate production from glycerol in mixed culture fermentation.

    PubMed

    Chen, Yun; Wang, Ting; Shen, Nan; Zhang, Fang; Zeng, Raymond J

    2016-11-01

    High-purity propionate production from glycerol in mixed culture fermentation (MCF) induced by high ammonium concentration was investigated. Fed-batch experiments revealed that higher ammonium concentration (>2.9g/L) had simultaneous negative effects on acetate and propionate degradation. Propionate production and yield was up to 22.6g/L and 0.45g COD/g COD glycerol, respectively, with a purity of 96%. Sequential batch experiments demonstrated that the yields of propionate were 0.3±0.05, 0.32±0.01, and 0.34±0.03g COD/g COD at a glycerol concentration of 2.78, 4.38, and 5.56g/L, respectively, and the purity of propionate was 91-100%. Microbial community analysis showed that the phylum Firmicutes dominated the bacterial community at different glycerol concentrations. However, the Methanosaeta population decreased from 46% to 6% when glycerol concentration increased from 2.78 to 5.56g/L, resulting in lower acetate degradation rate. Thus, the present study might provide an alternative option for the production of propionate from glycerol via MCF.

  4. [Maize Hybrid Seed Purity Identification Based on Near Infrared Reflectance (NIR) and Transmittance (NIT) Spectra].

    PubMed

    Li, Tian-xin; Jia, Shi-qiang; Liu, Xu; Zhao, Sheng-yi; Ran, Hang; Yan, Yan-lu; An, Dong

    2015-12-01

    This article explore the feasibility of using Near Infrared Reflectance (NIR) and Transmittance (NIT) Spectroscopy (908.1-1677.2 nm wavelength range) to identify maize hybrid purity, and compare the performance of NIR and NIT spectroscopy. Principle Component Analysis (PCA) and Orthogonal Linear Discriminant Analysis (OLDA) were used to reduce the dimension of spectra which have been pretreated by first derivative and vector normalization. The hybrid purity identification model of Nonghua101 and Jingyu16 were built by SVM. Models based on NIR spectra obtained correct identification rate as 100% and 90% for Nonghua101 and Jingyu16 respectively. But NIR spectra were greatly influenced by the placement of seeds, and there existed significant difference between NIR spectra of embryo and non-embryo side. Models based on NIT spectroscopy yielded correct identification rate as 98% both for Nonghua101 and Jingyu16. NIT spectra of embryo and non-embryo side were highly similar. The results indicate that it is feasible to identify maize hybrid purity based on NIR and NIT spectroscopy, and NIT spectroscopy is more suitable to analyze single seed kernel than NIR spectroscopy.

  5. Factors influencing the purity of electronic grade phosphine delivered to MOCVD tools

    NASA Astrophysics Data System (ADS)

    Feng, Jun; Owens, Mitch; Raynor, Mark W.

    2010-04-01

    Increasing mobility of InP films with usage time of one PH 3 cylinder prompted an investigation into factors influencing the purity of delivered PH 3. The presence of hygroscopic H xPO y residues in a delivery system greatly increases the dry-down time compared to that of a clean system. Static delivery system tests show increasing H 2O concentration with time and twice the increase in PH 3 versus N 2 over 48 h indicating reaction of metal oxides in components with PH 3 to generate H 2O. Gas purity may also vary during cylinder usage. Depletion of a high-purity PH 3 cylinder shows consistently low gas phase H 2O levels before phase-break but increasing levels after phase-break, as the cylinder depressurizes. The results highlight the importance of using pure PH 3, employing rigorous cycle-purging procedures to prevent H xPO y contamination, switching out cylinders in good time and using purification technology to control H 2O.

  6. Asymptotic geometric phase and purity for phase qubit dispersively coupled to lossy LC circuit

    SciTech Connect

    Mohamed, A.-B.A.; Obada, A.-S.F.

    2011-09-15

    Analytical descriptions of the geometric phases (GPs) for the total system and subsystems are studied for a current biased Josephson phase qubit strongly coupled to a lossy LC circuit in the dispersive limit. It is found that, the GP and purity depend on the damping parameter which leads to the phenomenon of GP death. Coherence parameter delays the phenomenon of a regular sequence of deaths and births of the GP. The asymptotic behavior of the GP and the purity for the qubit-LC resonator state closely follow that for the qubit state, but however, for the LC circuit these asymptotic values are equal to zero. - Highlights: > The model of a current biased Josephson phase qubit, strongly coupled to loss LC circuit, is considered. > Analytical descriptions of the geometric phase (GP) of this model, in the dispersive limit, are studied. > The GP and purity depend on the dissipation which leads to the GP death phenomenon. > Coherence parameter delays the phenomenon of a regular sequence of deaths and births of the GP.

  7. Temporal Purity and Quantum Interference of Single Photons from Two Independent Cold Atomic Ensembles

    NASA Astrophysics Data System (ADS)

    Qian, Peng; Gu, Zhenjie; Cao, Rong; Wen, Rong; Ou, Z. Y.; Chen, J. F.; Zhang, Weiping

    2016-07-01

    The temporal purity of single photons is crucial to the indistinguishability of independent photon sources for the fundamental study of the quantum nature of light and the development of photonic technologies. Currently, the technique for single photons heralded from time-frequency entangled biphotons created in nonlinear crystals does not guarantee the temporal-quantum purity, except using spectral filtering. Nevertheless, an entirely different situation is anticipated for narrow-band biphotons with a coherence time far longer than the time resolution of a single-photon detector. Here we demonstrate temporally pure single photons with a coherence time of 100 ns, directly heralded from the time-frequency entangled biphotons generated by spontaneous four-wave mixing in cold atomic ensembles, without any supplemented filters or cavities. A near-perfect purity and indistinguishability are both verified through Hong-Ou-Mandel quantum interference using single photons from two independent cold atomic ensembles. The time-frequency entanglement provides a route to manipulate the pure temporal state of the single-photon source.

  8. Simple HPLC method for detection of trace ephedrine and pseudoephedrine in high-purity methamphetamine.

    PubMed

    Makino, Yukiko

    2012-03-01

    A simple and sensitive HPLC technique was developed for the qualitative determination of ephedrine and pseudoephedrine (ephedrines), used as precursors of clandestine d-methamphetamine hydrochloride of high purity. Good separation of ephedrines from bulk d-methamphetamine was achieved, without any extraction or derivatization procedure on a CAPCELLPACK C18 MGII (250 × 4.6 mm) column. The mobile phase consisted of 50 mM KH2 PO4-acetonitrile (94:6 v/v %) using an isocratic pump system within 20 min for detecting two analytes. One run took about 50 min as it was necessary to wash out overloaded methamphetamine for column conditioning. The analytes were detected by UV absorbance measurement at 210 nm. A sample (20 mg) was simply dissolved in 1 mL of water, and a 50 μL aliquot of the solution was injected into the HPLC. The detection limits for ephedrine and pseudoephedrine in bulk d-methamphetamine were as low as 3 ppm each. This analytical separation technique made it possible to detect ephedrine and/or pseudoephedrine in seven samples of high-purity d-methamphetamine hydrochloride seized in Japan. The presence of trace ephedrines in illicit methamphetamine may strongly indicate a synthetic route via ephedrine in methamphetamine profiling. This method is simple and sensitive, requiring only commonly available equipment, and should be useful for high-purity methamphetamine profiling.

  9. Efficient purification of high-purity compounds from the stem of Lonicera japonica Thunb using two-dimensional preparative chromatography.

    PubMed

    Jin, Hongli; Liu, Yanfang; Feng, Jiatao; Guo, Zhimou; Wang, Chaoran; Zhong, Zhengsheng; Peng, Xiaojun; Dang, Jun; Tao, Yanduo; Liang, Xinmiao

    2013-08-01

    Purification of high-purity compounds from traditional Chinese medicines (TCMs) plays an important role in investigating their bioactivity. Nevertheless, it is often quite difficult to isolate compounds with high purity because of the complexity of TCMs in chemical composition. In this work, a two-dimensional preparation method was successfully developed for the preparation of high-purity compounds from the stem of Lonicera japonica Thunb, based on two novel polar copolymerized RP stationary phases, XAqua C3 and XAqua C18. An XAqua C3 prep column was used to separate the sample in the first-dimensional preparation, and 14 g of sample was fractionated into eight fractions with a recovery of 82%. An XAqua C18 prep column was selected to prepare high-purity compounds in the second-dimensional preparation for its good orthogonality with the XAqua C3 stationary phase. As a result, major compounds in the sample were isolated with more than 99% purity. This method is a potent method to realize the efficient purification of compounds with high purity from the stem of L. japonica Thunb and it shows great potential in the separation of high-purity compounds from complex samples.

  10. [Possibilities of systemic radiotherapy with high-purity 89Sr chloride in the treatment of bone metastases].

    PubMed

    Fomin, D K; Tararukhina, O B; Nazarov, A A

    2012-01-01

    To study the efficiency of treatment via single administration of high-purity 89Sr chloride in the standard activity of 150 MBq for pain syndrome in patients with multiple bone metastases. The authors carried out clinical trials of high-purity 89Sr chloride used to treat 30 patients with multiple bone metastases from cancers at various sites. The results of treatment were analyzed in 30 patients with multiple bone metastases, who had received systemic radiation therapy with high-purity 89Sr chloride in the standard activity of 150 MBq. These were assessed using some indicators: the intensity of pain syndrome and the blood concentrations of hemoglobin, leukocytes, and platelets. There was evidence for the use of high-purity 89Sr chloride in the therapy of patients with cancer at various sites with multiple bone metastases. The major indicators (pain syndrome, the blood concentrations of hemoglobin, leukocytes, and platelets) were compared before and after the treatment. These were also compared with those obtained with the use of usual 89Sr chloride. The therapeutic action of high-purity 89Sr chloride is comparable with that of 89Sr chloride in the standard activity; moreover, the analgesic effect of high-purity 89Sr chloride is being significantly higher. It has less significant myelotoxic activity than usual 89Sr chloride. High-purity 89Sr chloride is an effective radiopharmaceutical agent and may be used for systemic radiotherapy in patients with multiple bone metastatic lesion.

  11. High-frequency drug purity and price series as tools for explaining drug trends and harms in Victoria, Australia.

    PubMed

    Scott, Nick; Caulkins, Jonathan P; Ritter, Alison; Quinn, Catherine; Dietze, Paul

    2015-01-01

    Methamphetamine-related harms in Victoria have increased recently in the context of stable or declining use prevalence. We determine how changes in price and purity of methamphetamine compared to other drugs such as heroin may, in part, explain these divergent patterns. Detailed methamphetamine and heroin purchase price data from 2152 participant interviews from the Melbourne Injecting Drug User cohort study were used to generate drug price series for the period January 2009-June 2013. Data on drug purity from 8818 seizures made within Victoria were used to generate drug purity series during the same period. Purity-adjusted price data for methamphetamine and heroin were obtained for the period 2009-13 by combining the two data sets. While the average purity of heroin seizures remained consistent and low, the average purity of powder and of crystal methamphetamine seizures increased from 12% [95% confidence interval (CI) = 10-14%] to 37% (95% CI = 20-54%) and 21% (95% CI = 18-23%) to 64% (95% CI = 60-68%), respectively. Crystal methamphetamine purity was bimodal, with observations generally less than 20% or greater than 70%. The average unadjusted price per gram for heroin decreased from $374 (95% CI = $367-381) to $294 (95% CI = $280-308), powder methamphetamine did not change significantly from $252 (95% CI = $233-271), and crystal methamphetamine increased substantially from $464 (95% CI = $416-511) in 2009 to $795 (95% CI = $737-853) in 2011. This increase was offset by an even greater increase in purity, meaning the average purity-adjusted price per gram declined. Furthermore, pure prices of both methamphetamine forms were similar, whereas their unadjusted prices were not. The pure price of heroin fluctuated with no ongoing trends. Decreases in methamphetamine purity-adjusted price along with the bimodality of crystal methamphetamine purity may account for some of the recent increase in methamphetamine-related harm. For a

  12. Switching between purification and contamination regimes governed by the ionic purity of nanoparticles dispersed in liquid crystals

    NASA Astrophysics Data System (ADS)

    Garbovskiy, Yuriy

    2016-03-01

    This paper reports non-trivial effects of the ionic purity of nanoparticles on the concentration of ions in liquid crystals. Nanoparticles dispersed in liquid crystals can affect the concentration of mobile ions in different ways. 100% pure nanoparticles can only decrease the concentration of ions by means of adsorption/desorption processes. Liquid crystals doped with contaminated nanoparticles exhibit three regimes, namely, the purification, contamination, and no change in the concentration of ions. Switching between these regimes is governed by three dominant factors: the purity of liquid crystals, the purity of nanoparticles, and the ratio of the adsorption rate to the desorption rate.

  13. Determination of traces of rubidium in high purity cesium chloride by electrothermal atomic absorption spectrometry (ETAAS) using boric acid as a modifier.

    PubMed

    Dash, K; Thangavel, S; Chaurasia, S C; Arunachalam, J

    2007-02-12

    The use of boric acid as a modifier for the determination of trace amount of rubidium in high purity cesium chloride matrix by electrothermal atomic absorption is described. It was found that the negative influence of the chloride matrix could not be eliminated using stabilized temperature platform (STPF) alone. Due to the high dissociation energy (D(0)=427 kJ mol(-1)) of rubidium chloride, it was difficult to dissociate in the gas phase and hence is lost. Elimination of interferences was achieved by the addition of boric acid as a chemical modifier. Diluted cesium chloride samples (5%, m/v) were analyzed applying the standard addition method. The characteristic mass of 24 pg was obtained. The detection limit of the proposed method is around 26 ng g(-1). The developed method was applied to the determination of traces of rubidium in high purity cesium chloride samples. The data obtained by this method were in good agreement with those obtained by other independent method like FAAS.

  14. Development of a system to evaluate compound identity, purity, and concentration in a single experiment and its application in quality assessment of combinatorial libraries and screening hits.

    PubMed

    Yurek, David A; Branch, Derek L; Kuo, Ming-Shang

    2002-01-01

    The development and use of a new assay system for the simultaneous determination of identity, purity, and concentration of sample components from combinatorial libraries produced by parallel synthesis are described. The system makes use of high-performance liquid chromatography with UV/vis photodiode array (PDA), evaporative light scattering (ELSD), chemiluminescent nitrogen (CLND), and time-of-flight mass spectrometer (TOFMS) detectors (HPLC-PDA-ELSD-CLND-TOFMS). Although these detectors have previously been utilized separately for the analysis of combinatorial chemistry libraries, the use of TOFMS along with CLND provides a synergistic combination enabling target and side-product structures to be identified and their concentrations and purities determined in a single experiment from a solution containing microgram levels of material. The CLND was found to give a linear response based on the number of moles of nitrogen present. Therefore, if the number of nitrogens per molecule is known, the concentration of each nitrogen-containing sample component may be determined utilizing an unrelated co-injected standard. A molecular formula for an impurity may often be calculated from the exact mass determined by the TOFMS and knowledge of the chemistry involved. Thus, if the sample components contain nitrogen, the concentration of every identified HPLC peak may be determined even in the absence of primary standards. This combination of detectors enabled the characterization of both target compounds and byproducts in combinatorial libraries, allowing the optimization of library synthetic procedures. This system was also used to survey the quality of libraries, enabling the selection of the best libraries for screening. This method also facilitated the characterization of samples from combinatorial libraries found as hits in high-throughput screening to establish the potency of the leads based on their actual concentration. In addition, concentrations and potencies of

  15. Assessment of the purity of isolated cell populations for lineage-specific chimerism monitoring post haematopoietic stem cell transplantation.

    PubMed

    Hanson, V; Adams, B; Lord, J; Barker, A; Poulton, K; Lee, H

    2013-10-01

    Following haematopoietic stem cell transplantation, monitoring the proportion of donor and recipient haematopoiesis in the patient (chimerism) is an influential tool in directing further treatment choices. Short tandem repeat (STR) analysis is a method of chimerism monitoring using DNA isolated from peripheral blood, bone marrow or specific isolated cell lineages such as CD3+ T cells. For lineage-specific STR analysis on cell populations isolated from peripheral blood, a qualitative estimation of the purity of each isolated population is essential for the correct interpretation of the test data. We describe a rapid, inexpensive method for the determination of purity using a simple flow cytometry method. The method described for assessing the purity of sorted CD3+ cells can be applied to any cell population isolated using the same technology. Data obtained were comparable to results from a commercial polymerase chain reaction (PCR)-based method for the assessment of purity (Non-T Genomic Detection Kit, Accumol, Calgary, AB, Canada) (P = 0.59). Of the 303 samples tested by flow cytometry, 290 (95.7%) exceeded 90% purity, and 215 (70.95%) were over 99% pure. There were some outlying samples, showing diversity between samples and the unpredictability of purity of isolated cell populations. This flow cytometry method can be easily assimilated into routine testing protocols, allowing purity assessment in multiple-sorted cell populations for lineage-specific chimerism monitoring using a single secondary antibody and giving results comparable to a PCR-based method. As purity of isolated cell lineages is affected by time after venepuncture and storage temperature, assessment of each sample is recommended to give a reliable indication of sample quality and confidence in the interpretation of the results. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. Process for producing high purity silicon nitride by the direct reaction between elemental silicon and nitrogen-hydrogen liquid reactants

    DOEpatents

    Pugar, Eloise A.; Morgan, Peter E. D.

    1990-01-01

    A process is disclosed for producing, at a low temperature, a high purity reaction product consisting essentially of silicon, nitrogen, and hydrogen which can then be heated to produce a high purity alpha silicon nitride. The process comprises: reacting together a particulate elemental high purity silicon with a high purity nitrogen-hydrogen reactant in its liquid state (such as ammonia or hydrazine) having the formula: N.sub.n H.sub.(n+m) wherein: n=1-4 and m=2 when the nitrogen-hydrogen reactant is straight chain, and 0 when the nitrogen-hydrogen reactant is cyclic. High purity silicon nitride can be formed from this intermediate product by heating the intermediate product at a temperature of from about 1200.degree.-1700.degree. C. for a period from about 15 minutes up to about 2 hours to form a high purity alpha silicon nitride product. The discovery of the existence of a soluble Si-N-H intermediate enables chemical pathways to be explored previously unavailable in conventional solid state approaches to silicon-nitrogen ceramics.

  17. Process for producing high purity silicon nitride by the direct reaction between elemental silicon and nitrogen-hydrogen liquid reactants

    DOEpatents

    Pugar, E.A.; Morgan, P.E.D.

    1987-09-15

    A process is disclosed for producing, at a low temperature, a high purity reaction product consisting essentially of silicon, nitrogen, and hydrogen which can then be heated to produce a high purity alpha silicon nitride. The process comprises: reacting together a particulate elemental high purity silicon with a high purity nitrogen-hydrogen reactant in its liquid state (such as ammonia or hydrazine) having the formula: N/sub n/H/sub (n+m)/ wherein: n = 1--4 and m = 2 when the nitrogen-hydrogen reactant is straight chain, and 0 when the nitrogen-hydrogen reactant is cyclic. High purity silicon nitride can be formed from this intermediate product by heating the intermediate product at a temperature of from about 1200--1700/degree/C for a period from about 15 minutes up to about 2 hours to form a high purity alpha silicon nitride product. The discovery of the existence of a soluble Si/endash/N/endash/H intermediate enables chemical pathways to be explored previously unavailable in conventional solid-state approaches to silicon-nitrogen ceramics

  18. Correlation between cocaine prices and purity with trends in emergency department visits in a major metropolitan area.

    PubMed

    Zhu, He; Wilson, Fernando A; Stimpson, Jim P; Pagán, José A

    2014-10-01

    Illicit drug use not only causes acute and chronic adverse health outcomes but also results in a significant burden to health care providers. The objective of this study is to examine the relationship between cocaine prices and purity with emergency department (ED) visits for the Chicago-Naperville-Joliet metropolitan area. Our primary outcome was number of cocaine-related ED visits per quarter provided by the Drug Abuse Warning Network. The predictor variables of cocaine purity and price were provided by the System to Retrieve Information from Drug Evidence database. Autoregressive integrated moving average (ARIMA) regressions were used to estimate the effects of cocaine price and purity on cocaine-related ED visits. Although cocaine prices did not change substantially over time, cocaine purity decreased by over 30 % between 2006 and 2010. ARIMA regression results suggest that cocaine-related ED visits were not significantly associated with powder or crack cocaine prices; however, a decrease in powder cocaine purity was associated with 2,081 fewer ED visits overall from 2007 to 2010. The cocaine trade continues to be a major public health and law enforcement threat to large metropolitan cities like Chicago. Regular monitoring of cocaine purity levels may provide early warning of impending changes in cocaine-related ED visits for law enforcement and health care providers.

  19. The relevance of moral norms in distinct relational contexts: Purity versus harm norms regulate self-directed actions

    PubMed Central

    Dungan, James A.; Chakroff, Alek; Young, Liane

    2017-01-01

    Recent efforts to partition the space of morality have focused on the descriptive content of distinct moral domains (e.g., harm versus purity), or alternatively, the relationship between the perpetrator and victim of moral violations. Across three studies, we demonstrate that harm and purity norms are relevant in distinct relational contexts. Moral judgments of purity violations, compared to harm violations, are relatively more sensitive to the negative impact perpetrators have on themselves versus other victims (Study 1). This pattern replicates across a wide array of harm and purity violations varying in severity (Studies 2 and 3). Moreover, while perceptions of harm predict moral judgment consistently across relational contexts, perceptions of purity predict moral judgment more for self-directed actions, where perpetrators violate themselves, compared to dyadic actions, where perpetrators violate other victims (Study 3). Together, these studies reveal how an action’s content and its relational context interact to influence moral judgment, providing novel insights into the adaptive functions of harm and purity norms. PMID:28278214

  20. The relevance of moral norms in distinct relational contexts: Purity versus harm norms regulate self-directed actions.

    PubMed

    Dungan, James A; Chakroff, Alek; Young, Liane

    2017-01-01

    Recent efforts to partition the space of morality have focused on the descriptive content of distinct moral domains (e.g., harm versus purity), or alternatively, the relationship between the perpetrator and victim of moral violations. Across three studies, we demonstrate that harm and purity norms are relevant in distinct relational contexts. Moral judgments of purity violations, compared to harm violations, are relatively more sensitive to the negative impact perpetrators have on themselves versus other victims (Study 1). This pattern replicates across a wide array of harm and purity violations varying in severity (Studies 2 and 3). Moreover, while perceptions of harm predict moral judgment consistently across relational contexts, perceptions of purity predict moral judgment more for self-directed actions, where perpetrators violate themselves, compared to dyadic actions, where perpetrators violate other victims (Study 3). Together, these studies reveal how an action's content and its relational context interact to influence moral judgment, providing novel insights into the adaptive functions of harm and purity norms.

  1. Recycling of high purity selenium from CIGS solar cell waste materials

    SciTech Connect

    Gustafsson, Anna M.K. Foreman, Mark R.StJ.; Ekberg, Christian

    2014-10-15

    Highlights: • A new method for recycling of selenium from CIGS solar cell materials is presented. • Separation of selenium as selenium dioxide after heating in oxygen atmosphere. • Complete selenium separation after oxidation of <63 μm particles at 800 °C for 1 h. • After reduction of selenium dioxide the selenium purity was higher than 99.999 wt%. - Abstract: Copper indium gallium diselenide (CIGS) is a promising material in thin film solar cell production. To make CIGS solar cells more competitive, both economically and environmentally, in comparison to other energy sources, methods for recycling are needed. In addition to the generally high price of the material, significant amounts of the metals are lost in the manufacturing process. The feasibility of recycling selenium from CIGS through oxidation at elevated temperatures was therefore examined. During oxidation gaseous selenium dioxide was formed and could be separated from the other elements, which remained in solid state. Upon cooling, the selenium dioxide sublimes and can be collected as crystals. After oxidation for 1 h at 800 °C all of the selenium was separated from the CIGS material. Two different reduction methods for reduction of the selenium dioxide to selenium were tested. In the first reduction method an organic molecule was used as the reducing agent in a Riley reaction. In the second reduction method sulphur dioxide gas was used. Both methods resulted in high purity selenium. This proves that the studied selenium separation method could be the first step in a recycling process aimed at the complete separation and recovery of high purity elements from CIGS.

  2. Development of low-loss cryo-accelerating structure with high-purity copper

    NASA Astrophysics Data System (ADS)

    Iino, Akihiro; Yamaguchi, Seiya; Shintomi, Takakazu; Higo, Toshiyasu; Funahashi, Yoshisato; Matsumoto, Shuji; Michizono, Shinichiro; Ueno, Kenji; Endo, Katsumi

    2017-09-01

    In this paper, the development of an accelerating structure with high-purity copper operated at approximately 20 K is described. The aim is to obtain a dramatic increase in the quality factor (Q factor), which is an important parameter as regards enhancement of the acceleration gradient in a normal-conducting accelerating structure that has been operated at room temperature in the past. First, the Q factors of pillbox cavities comprised of two types of copper with different purities (99.99% and 99.99998%) were measured, at room temperature (300 K) and at a relatively low temperature (20 K); the resultant ratios, Q0(20 K)/Q0(300 K), were then compared with calculated values. Hence, it was found that the experimental and calculated values agree to within several percent, and converge to a constant value (approximately 5.3) when the residual resistance ratio is above 500. Next, a C-band accelerating structure was fabricated using a copper material having a purity of 99.99998%, and high-power testing of the structure was conducted at 20 K. Hence, it was found that the accelerating gradient Eacc reaches 30.9 MV/m with a 1.0-μs pulse width and 50-Hz repetition rate. In the high-power test, it was revealed that the radiation dose rate for C-band structure (20 K) was about two orders of magnitude lower than that for S-band structure (303 K) under the same conditions. Further, the magnitude of the dark current generated in this structure was estimated to be several femtoamps, which was below the detection limit. This finding was based on the assumption that the dark current magnitude is proportional to the radiation dose; however, no dark current was observed.

  3. Understanding Friction and Wear Mechanisms of High-Purity Titanium against Steel in Liquid Nitrogen Temperature

    NASA Astrophysics Data System (ADS)

    Basu, Bikramjit; Sarkar, J.; Mishra, Ravi

    2009-02-01

    Although the friction and wear properties of several metallic alloys in unlubricated conditions are widely investigated, such understanding for high-purity metals in cryogenic environment is rather limited. This article reports the tribological properties of high-purity α-titanium ( α-Ti), prepared by cold rolling and recrystallization annealing, under liquid nitrogen (LN2) and room temperature (RT) environments against steel (bearing grade: SAE 52100) at varying loads (up to 15 N) and sliding speeds (0.6 to 4.19 m/s). It has been found that the steady-state coefficient of friction (COF) of titanium under LN2 environment (˜0.27 to 0.33) is lower than that at RT COF (˜0.33 to 0.58) irrespective of sliding speed. For cryogenic sliding conditions, the COF decreased steadily with sliding speed to a mean value of about 0.28 and no appreciable variation in COF is noticed for sliding speed of more than 1.5 m/s. The wear rate under both environment conditions was of the order of 10-3 mm3 N-1 m-1 irrespective of variation in operating parameters, but the RT wear rate was found to be higher compared to the LN2 case. Overall, the experimental results demonstrate improved tribological properties of high-purity titanium at LN2 temperature compared to the RT. Flow localization at tribological interfaces because of the large strain rate and subsequent damage accumulation at the titanium test piece are some of the attributes of the wear of Ti at LN2 temperature. In addition, the galling of titanium was also observed to occur under large contact stress and sliding speed conditions.

  4. Generation of high-purity low-temperature samples of 39K for applications in metrology

    NASA Astrophysics Data System (ADS)

    Antoni-Micollier, L.; Barrett, B.; Chichet, L.; Condon, G.; Battelier, B.; Landragin, A.; Bouyer, P.

    2017-08-01

    We present an all-optical technique to prepare a sample of 39K in a magnetically insensitive state with 95% purity while maintaining a temperature of 6 μ K . This versatile preparation scheme is particularly well suited to performing matter-wave interferometry with species exhibiting closely separated hyperfine levels, such as the isotopes of lithium and potassium, and opens new possibilities for metrology with these atoms. We demonstrate the feasibility of such measurements by realizing an atomic gravimeter and a Ramsey-type spectrometer, both of which exhibit a state-of-the-art sensitivity for cold potassium.

  5. Radio-UHPLC: a tool for rapidly determining the radiochemical purity of technetium-99m radiopharmaceuticals?

    PubMed

    Kryza, David; Janier, Marc

    2013-08-01

    Determining the radiochemical purity (RCP) of technetium-99m ((99m)Tc) radiopharmaceuticals using the method described in the package insert is a time-consuming process, requiring particular attention in order to achieve accurate RCP results. The purpose of this study was to evaluate whether radio-ultra high performance liquid chromatography (radio-UHPLC) may be an alternative method for RCP testing of (99m)Tc-tetrofosmin, (99m)Tc-MAG3 and (99m)Tc-sestamibi. Results obtained using radio-UHPLC were in excellent agreement with the standard method, with total analysis time being reduced to less than 3 min.

  6. Preparation of ammonia borane in high yield and purity, methanolysis, and regeneration.

    PubMed

    Ramachandran, P Veeraraghavan; Gagare, Pravin D

    2007-09-17

    Ammonia borane (AB) is emerging as a promising solid hydrogen carrier, particularly for power generation in portable devices that employ proton-exchange membrane fuel cells. A preparative-scale synthesis of AB from sodium borohydride and ammonium salts in high yields (> or =95%) and very high purity (> or =98%) has been described. The first systematic study of a transitional metal-catalyzed alcoholysis of AB, comparison of the methanolysis to the hydrolysis of AB, and regeneration of AB from ammonium tetramethoxyborate also has been described.

  7. Relations between quantum correlations, purity and teleportation fidelity for the two-qubit Heisenberg XYZ system

    NASA Astrophysics Data System (ADS)

    Qin, Meng; Li, Yan-Biao; Wu, Fang-Ping

    2014-07-01

    Quantifying and understanding quantum correlations may give a direct reply for many issues regarding the interesting behaviors of quantum system. To explore the quantum correlations in quantum teleportation, we have used a two-qubit Heisenberg XYZ system with spin-orbit interaction as a quantum channel to teleport an unknown state. By using different measures and standard teleportation protocols, we have derived the analytical expressions for quantum discord, entanglement of formation, purity, and maximal teleportation fidelity of the system. We compare their different characteristics and analyze the relationships between these quantities.

  8. High-purity cobalt thin films with perpendicular magnetic anisotropy prepared by chemical vapor deposition

    NASA Astrophysics Data System (ADS)

    Ootera, Yasuaki; Shimada, Takuya; Kado, Masaki; Quinsat, Michael; Morise, Hirofumi; Nakamura, Shiho; Kondo, Tsuyoshi

    2015-11-01

    A study of the chemical vapor deposition (CVD) of high-purity cobalt thin films is described. The Co layer prepared by a thermal CVD technique with a Pt/Ta underlayer and a Pt cap layer shows a saturation magnetization (Ms) of ∼1.8 T and perpendicular magnetic anisotropy (PMA) with an anisotropy energy (Ku) of ∼105 J/m3. The cobalt thickness dependence of Ku reveals that the interfacial anisotropy at the Pt/Co interface is most likely the origin of the obtained PMA.

  9. Process for the production of ultrahigh purity silane with recycle from separation columns

    DOEpatents

    Coleman, Larry M.

    1982-07-20

    Tri- and dichlorosilanes formed by hydrogenation in the course of the reaction of metallurgical silicon, hydrogen and recycle silicon tetrachloride are employed as feed into a separation column arrangement of sequential separation columns and redistribution reactors which processes the feed into ultrahigh purity silane and recycle silicon tetrachloride. A slip stream is removed from the bottom of two sequential columns and added to the recycle silicon tetrachloride process stream causing impurities in the slip streams to be subjected to reactions in the hydrogenation step whereby waste materials can be formed and readily separated.

  10. Formation and evolution of tweed structures on high-purity aluminum polycrystalline foils under cyclic tension

    SciTech Connect

    Kuznetsov, P. V.; Vlasov, I. V.; Sklyarova, E. A.; Smekalina, T. V.

    2015-10-27

    Peculiarities of formation and evolution of tweed structures on the surface of high-purity aluminum polycrystalline foils under cyclic tension were studied using an atom force microscope and a white light interferometer. Tweed structures of micron and submicron sizes were found on the foils at different number of cycles. In the range of 42,000 < N < 95,000 cycles destruction of tweed patterns is observed, which leads to their disappearance from the surface of the foils. Formation of tweed structures of various scales is discussed in terms of the Grinfeld instability.

  11. New red phosphor for near-ultraviolet light-emitting diodes with high color-purity

    SciTech Connect

    Wang, Zhengliang; He, Pei; Wang, Rui; Zhao, Jishou; Gong, Menglian

    2010-02-15

    New red phosphors, Na{sub 5}Eu(MoO{sub 4}){sub 4} doped with boron oxide were prepared by the solid-state reaction. Their structure and photo-luminescent properties were investigated. With the introduction of boron oxide, the red emission intensity of the phosphors under 395 nm excitation is strengthened, with high color-purity (x = 0.673, y = 0.327). The single red light-emitting diode was obtained by combining InGaN chip with the red phosphor, bright red light can be observed by naked eyes from the red light-emitting diodes under a forward bias of 20 mA.

  12. Impurity removal process for high-purity silica production by acid leaching

    NASA Astrophysics Data System (ADS)

    Khalifa, M.; Hajji, M.; Ezzaouia, H.

    2012-06-01

    In our days obtaining silica sand with very high purity is a primordial stage in photovoltaic industry. The effects of acids on the removal of impurity from silica sand have been studied using leaching acids: mixture composed of HF/HCl/H2O with a volume composition of (1:7:24).The obtained material was characterized using Ultraviolet-Visible absorbance (UV-Vis) and Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES). Results of the application of this technique show a significant reduction of the amounts of undesirable impurities present in natural silica (such as Co, Fe, Ca, Al, Mg …).

  13. [Progress on methods for purity assessment of separated chromosome X- or Y-bearing sperm].

    PubMed

    Guo, Jia-Ming; Zhu, Hua-Bin; Wang, Dong; Zhang, Lin-Bo; Hao, Hai-Sheng; DU, Wei-Hua

    2008-09-01

    In this review of methods for purity assessment of isolated chromosome X- and Y-bearing sperm, we compared the principles, operating procedures, as well as pros and cons for various methods. We conclude that nested PCR of single sperm will become a conventional and popular method with lower costs, and the method will play a very important role in optimizing the X, Y sorting method, if the sensitivity and accuracy of the method can be increased and the testing time decreased, and promote the new progress in other genetic testing techniques on single sperm.

  14. Effects of Purity Level on the Mechanical Properties of 7000-Series Aluminums

    DTIC Science & Technology

    1980-10-01

    2124 as a derivative of 2024 and 7175 as a derivative of 7075. Within the 7000-series a large number of such alloys have been produced by lowering...AFWAL-TR-80-4079 E n EFFECTS OF PURITY LEVEL ON THE MECHANICAL PROPERTIES OF o 7000-SERIES ALUMINUMS SG. J. Petrak : Materials Integrity Branch T...e,--e#le, d, if ,,o -ny Slid ’de’fy bii,,hi k n~IT.-t- Aluminum .’ I" Tensile ?C,00-Spries Fracture Toughness Punit’ F3tigque IIIIrUuri ty Fatigue

  15. High-precision efficiency calibration of a high-purity co-axial germanium detector

    NASA Astrophysics Data System (ADS)

    Blank, B.; Souin, J.; Ascher, P.; Audirac, L.; Canchel, G.; Gerbaux, M.; Grévy, S.; Giovinazzo, J.; Guérin, H.; Nieto, T. Kurtukian; Matea, I.; Bouzomita, H.; Delahaye, P.; Grinyer, G. F.; Thomas, J. C.

    2015-03-01

    A high-purity co-axial germanium detector has been calibrated in efficiency to a precision of about 0.15% over a wide energy range. High-precision scans of the detector crystal and γ-ray source measurements have been compared to Monte-Carlo simulations to adjust the dimensions of a detector model. For this purpose, standard calibration sources and short-lived online sources have been used. The resulting efficiency calibration reaches the precision needed e.g. for branching ratio measurements of super-allowed β decays for tests of the weak-interaction standard model.

  16. Process for the production of ultrahigh purity silane with recycle from separation columns

    NASA Technical Reports Server (NTRS)

    Coleman, Larry M. (Inventor)

    1982-01-01

    Tri- and dichlorosilanes formed by hydrogenation in the course of the reaction of metallurgical silicon, hydrogen and recycle silicon tetrachloride are employed as feed into a separation column arrangement of sequential separation columns and redistribution reactors which processes the feed into ultrahigh purity silane and recycle silicon tetrachloride. A slip stream is removed from the bottom of two sequential columns and added to the recycle silicon tetrachloride process stream causing impurities in the slip streams to be subjected to reactions in the hydrogenation step whereby waste materials can be formed and readily separated.

  17. Formation of High-Purity Indium Oxide Nanoparticles and Their Application to Sensitive Detection of Ammonia

    PubMed Central

    Bhardwaj, Sanjeev K.; Bhardwaj, Neha; Kukkar, Manil; Sharma, Amit L.; Kim, Ki-Hyun; Deep, Akash

    2015-01-01

    High-purity In2O3 nanoparticles were recovered from scrap indium tin oxide substrates in a stepwise process involving acidic leaching, liquid-liquid extraction with a phosphine oxide extractant, and combustion of the organic phase. The morphological and structural parameters of the recovered nanoparticles were investigated to support the formation of the desired products. These In2O3 nanoparticles were used for sensitive sensing of ammonia gas using a four-probe electrode device. The proposed sensor offered very quick response time (around 10 s) and highly sensitive detection of ammonia (at a detection limit of 1 ppm). PMID:26694415

  18. The preparation and detection of high purity silicon tetrachloride with optical fibres level

    NASA Astrophysics Data System (ADS)

    Wan, Ye; Zhao, Xiong; Guo, Shuhu; Yan, Dazhou; Yang, Dian; Wang, Lei

    2017-06-01

    This article showed a technology for producing high purity silicon tetrachloride with optical fiber level, which using the method of adsorption unite distillation, whose material belong to by-product of polysilicon system. This technology could remove chlorosilane, metal impurities and impurities containing hydrogen effectively. Test’s results showed that most indexes can meet or exceed the standards of Evonic, indicating that product produced by this technology can meet the demand of processing optical fiber preforms what is OVD level completely. This technology has the advantages of simple process, continuous operation, and large capacity and so on, and industrialization can be realized.

  19. Corrosion behavior of surface films on boron-implanted high purity iron and stainless steels

    NASA Technical Reports Server (NTRS)

    Kim, H. J.; Carter, W. B.; Hochman, R. F.; Meletis, E. I.

    1985-01-01

    Boron (dose, 2 x 10 to the 17th ions/sq cm) was implanted into high purity iron, AISI 316 austenitic stainless steel, and AISI 440C martensitic stainless steel, at 40 keV. The film structure of implanted samples was examined and characterized by contrast and diffraction analyses utilizing transmission electron microscopy. The effect of B(+) ion implantation on the corrosion behavior was studied using the potentiodynamic polarization technique. Tests were performed in deaerated 1 N H2SO4 and 0.1 M NaCl solutions. Scanning electron microscopy was used to examine the morphology of the corroded surfaces after testing.

  20. [Microbial air purity in hospitals. Operating theatres with air conditioning system].

    PubMed

    Krogulski, Adam; Szczotko, Maciej

    2010-01-01

    The aim of this study was to show the influence of air conditioning control for microbial contamination of air inside the operating theatres equipped with correctly working air-conditioning system. This work was based on the results of bacteria and fungi concentration in hospital air obtained since 2001. Assays of microbial air purity conducted on atmospheric air in parallel with indoor air demonstrated that air filters applied in air-conditioning systems worked correctly in every case. To show the problem of fluctuation of bacteria concentration more precisely, every sequences of single results from successive measure series were examined independently.