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61.
Matrix element of the Gallilean invariant nonrelativistic reduction of the pseudoscalar-pseudovector interaction has been
calculated for free pion absorption by a single nucleon inside the nucleus of16O. The Hartree-Fock wavefunctions obtained with the unitary-model-operator approach starting with the hard-core nucleon-nucleon
interaction have been used for the π-capturing nucleon in the initial state. The initial pion distortion in the presence of
nuclear field of the absorbing nucleus prior to its absorption together with the Coulomb interaction with the finite nuclear
size has been taken into account. The distortion of the emitted proton in the field of the residual nucleus has also been
considered. The differential cross-sections have been obtained and calculated results are compared with the previous experimental
and theoretical work. 相似文献
62.
The pressure dependence of thelo-to phonons in InAs has been investigated by Raman scattering using the diamond anvil cell. Indium arsenide transforms, presumably
to the rock-salt structure at 70±1 kbar. The mode Grüneisen parameters for thelo-to phonons are γ
lo
=0.99±0.03, γ
to
=1.2±0.03 respectively. The effective charge,e*
T
, for InAs decreases slightly with pressure and this trend is in accordance with the behaviour of other III–V zinc blende
structured semiconductors: The structural phase transition is discussed in the light of theoretical calculations for phase
stability of III–V compounds, as well as recent high pressure x-ray diffraction studies. 相似文献
63.
H. M. J. Goldschmidt N. C. V. Péquériaux J. De Jongh-Leuvenink 《Accreditation and quality assurance》2002,7(11):468-472
The European Foundation for Quality Management (EFQM) integral quality management model covers nine issues: five so-called
enabler criteria and four so-called result-oriented criteria. The first enabler criterion concerns leadership and covers all
kind of strategic management aspects. However, directly or indirectly, the leadership of the board of directors or its individual
members is characterized and scored. An even more explicate technique, originated in a totally different way, is the 360°
feedback evaluation method. In this paper both methods are compared and practiced on various individuals. A checklist was
developed to facilitate scoring in the EFQM leadership submodel. Both methods, although from a different origin, could be
linked easily, covered very similar aspects and gave results that were in excellent agreement with each other. The scoring
showed almost identical results, supporting in large the use of the integral EFQM model.
Received: 25 May 2002 Accepted: 17 July 2002
Presented at the European Conference on Quality in the Spotlight in Medical Laboratories, 7–9 October 2001, Antwerp, Belgium
Correspondence to H. M. J. Goldschmidt 相似文献
64.
Kabir-ud-DinEmail author S.?M.?Shakeel?Iqubal Zaheer?Khan 《Colloid and polymer science》2005,283(5):504-511
Kinetics of oxidation of DL-malic acid by water soluble colloidal MnO2 (prepared from potassium permanganate and sodium thiosulfate solutions) have been studied spectrophotometrically in the absence and presence of nonionic Triton X-100 surfactant. The reaction is autocatalytic and manganese(II) (reduction product of the colloidal MnO2) may be the autocatalyst. The order of the reaction is first in colloidal [MnO2] as well as in [malic acid] both in the absence and presence of the surfactant. The reaction has acid-dependent and acid-independent paths and, in the former case, the order is fractional in [H+]. The effect of externally added manganese(II) is complex. The results show that the rate constant increases as the manganese(II) concentration is increased. It is not possible to predict the exact dependence of the rate constants on manganese(II) concentration, which has a series of reactions with other reactants. In the presence of TX-100, the observed effect on k is catalytic up to a certain [TX-100]; thereafter, an inhibitory effect follows. The catalytic effect is explained in terms of the mathematical model proposed by Tuncay et al. (in Colloids Surf A Physicochem Eng Aspects 149:279 3). Activation parameters associated with the observed rate constants (kobs/k) have also been evaluated and discussed. 相似文献
65.
The catalytic reduction of acetophenone, methyl α-acetamidocinnamate, and dimethyl itaconate with alcohol-modified sodium borohydride was studied in the presence of complexes CoCl2·L2 (L2 are chiral C
2-symmetric diamines: (4S,5S)-2,2-dimethyl-4,5-bis(aminomethyl)-1,3-dioxolane, (4S, 5S)-2,2-dimethyl-4,5-bis(methylaminomethyl)-1,3-dioxolane, (4S, 5S)-2,2-dimethyl-4,5-bis(dimethylaminomethyl)-1,3-dioxolane, and (4S, 5S)-2,2-dimethyl-4,5-bis(diphenylaminomethyl)-1,3-dioxolane). The maximum enantiomeric excess of (S)-1-phenylethanol was 24%, that of dimethyl α-methylsuccinate was 38%.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 342–347, February, 2005. 相似文献
66.
Summary A high-performance liquid chromatographic method, with 9-anthryldiazomethane as derivatizing agent, has been developed for
the simultaneous determination ofN-carbamoyl aspartate andl-dihydroorotate in serum. Sample preparation for 1 mL serum was by simple liquid-liquid extraction and then derivatization.
The compounds were separated on a Luna C18(2) column by use of a gradient prepared from acetonitrile and 10 mM sodium acetate
buffer, pH 6.0, and fluorimetric detection was performed at excitation and emission wavelengths of 365 nm and 412 nm, respectively.
The response was found to be linearly dependent on concentration between 0.8 and 60 μg mL−1 forl-dihydrooratate and between 0.9 and 90 μg mL−1 forN-carbamoyl aspartate; the mean recovery rates were 50 and 51%, respectively. The limits of detection and quantification were
0.33 μg mL−1 and 0.6 μg mL−1, respectively, forl-dihydroorotate and 0.4 μg mL−1 and 0.7 μg mL−1 forN-carbamoyl aspartate. This method can be used to assess accumulation ofN-carbamoyl aspartate andl-dihydroorotate in body fluids in situations where cellular pyrimidine de novo synthesis is impaired. 相似文献
67.
A. V. Makarycheva-Mikhailova S. I. Selivanov N. A. Bokach V. Yu. Kukushkin P. F. Kelly A. J. L Pombeiro 《Russian Chemical Bulletin》2004,53(8):1681-1685
Reactions of the platinum(IV) nitrile complexes [PtCl4(RCN)2] (R = Me, CH2Ph, Ph) with 1,2- and 1,4-PhS(=NH)C6H4SPh in CH2Cl2 afforded addition products of sulfimides and coordinated nitriles, viz., the [PtCl4{NH=C(R)N=S(Ph)(C6H4SPh)}2] complexes. The latter were isolated in 75—90% yields and characterized by elemental analysis, positive-ion FAB mass spectrometry, IR spectroscopy, and 1H and 13C1H NMR spectroscopy. The temperature dependence of the 1H NMR spectra of the model [PtCl4{NH=C(R)N=SPh2}2] complexes (R = Me, Et) in CD2Cl2 studied in a temperature range from +40 to -70 °C demonstrated that E—Z isomerization of the ligands is a dynamic process in a range from +40 to -10 °C. The activation free energy of this process was calculated.Published in Russian in Izvestiya Akademii Nauk.
Seriya Khimicheskaya, No. 8, pp. 1618–1622, August, 2004. 相似文献
68.
O. A. Bogdanova E. I. Zhilyaeva R. N. Lyubovskaya N. S. Ovanesyan S. I. Pirumova O. S. Roskchupkina 《Russian Chemical Bulletin》1996,45(9):2210-2212
The synthesis, IR spectra, and the temperatures of the transition into a ferromagnetic state (T
c) of layered ferromagnetics [R3RX[MCr(C2O4)3 (M = Mn, Fe, Co, Cu, and Ni) with the [Ph3BuP]+, [Bu3RN]+ (R = Pr, Et, and Me) cations capable of subsequently changing the distances between metallooxalate layers have been considered. The temperatureT
c has been found to be independent of the size of the organic cation. It is believed that the determining factors in the transition to a ferromagnetic state are exchange interactions inside the metallooxalate layer.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2327–2330, September, 1996. 相似文献
69.
添加剂铜和银离子对MnO2催化燃烧CH4的影响 总被引:2,自引:1,他引:2
催化燃烧法,由于起燃温度低、去除率高、适用氧浓度范围大、无二次污染、燃烧缓和等,是国内外治理有机废气时,回收利用能量最有效的方法之一[1].但目前用于该过程的催化剂中均含有来源有限、价格昂贵的贵金属铂或钯[2].因此,寻找来源丰富、价格低廉、性能相当... 相似文献
70.
Qing-Shan Li Juan-Juan Xu Jian-Jiang Zhong 《Applied biochemistry and biotechnology》1997,62(2-3):243-250
Effects of water content and carbon and nitrogen sources on the production ofL-glutamate oxidase (GOD) by solid state fermentation (SSF) ofStreptomyces sp. N1 were investigated in a 250-mL shake flask. The results show that in the solid medium containing wheat bran 98% (w/w), KCl
0.2% (w/w), and MgCl2 0.2% (w/w), addition of 2.0-mL water per gram solid medium and 0.4% (w/w) (NH4)2SO4 was the best for GOD production. In this work, we also developed a simple technique forin situ measuring oxygen uptake rate (OUR) and carbon dioxide evolution rate (CER) in SSF in a shake flask based on the principle
of Warburg manometer. The method was successfully applied to determine OUR and CER values in SSF ofStreptomyces sp. N1. The results indicate that the largest OUR value was detected about one or two days ahead of the highest GOD activity reached
depending on the fermentation conditions, and the OUR may be used as anin situ indicator of GOD production in the SSF process. 相似文献