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61.
Measurements of the reflection spectra of polycrystalline CdxSr1−xO alloys (0 ? x ? 0.9) at 85 and 300 K in the spectral range of lattice vibrations (200–600 cm−1) are reported. By Kramers-Kronig analysis the optical constants and the LO-mode frequencies were evaluated. The samples showed essentially one-mode behaviour with marked fine structure of the low-temperature absorption for intermediate values of x. Up to now, applying the cluster model of Verleur and Barker has not yielded a tentative explanation. 相似文献
62.
63.
Y. H. Chen A. J. Kalinowski W. D. Pilkey 《Journal of Optimization Theory and Applications》1976,20(3):331-346
It is shown that an indirect synthesis method can be used in the efficient optimal design of multidegree-of-freedon, multidesignelement, nonlinear, transient systems. The technique begins with a limiting performance analysis which requires linear programming for a kinematically linear system, following which the system is selected using system identification methods such that the designed system responds as closely as possible to the limiting performance. The efficiency is a result of the method avoiding the repetitive systems analyses accompanying other numerical optimization methods.This investigation was supported by the NASA Langley Research Center, Grant No. NGR-47-005-145. 相似文献
64.
Summary Phenothiazine oxidizes at the dropping mercury electrode in waterethanolic solutions, containing 7 N sulphuric acid, giving a wave corresponding to the formation of free cation radicals.The normal potential of the system phenothiazine/radical, against the reference electrode formed from mercuric sulphate in the presence of 10 N H2SO4 and 30% ethanol, is –240±20 mV.In alkaline solutions of pH 12.5 phenothiazine also gives a polarographic wave. This wave corresponds to the insoluble anions of compounds formed with mercury. The conditions for the quantitative polarographic determination of phenothiazine are also given.
Dedicated to Prof. Dr. M. von Stackelberg on his 70th birthday. 相似文献
Zusammenfassung Es wurde bewiesen, daß in äthanolisch-wäßrigen Lösungen, die 7 n H2SO4 enthalten, Phenothiazin an der Quecksilber-Tropfelektrode oxydiert wird. Als Reaktionsprodukt entsteht ein freies Kation-Radikal. Das Normalpotential des Systems Phenothiazin/Radikal gegen die gesättigte Quecksilbersulfatelektrode, die 10 n H2SO4 und 30% C2H5OH enthält, beträgt –240 ± 20 mV.In alkalischen Lösungen bei pH 12,5 konnte man eine polarographische Welle registrieren, deren Eigenschaften schwerlöslichen Anionen einer Quecksilberverbindung entsprechen.Die Bedingungen für eine quantitative polarographische Phenothiazinbestimmung werden angegeben.
Dedicated to Prof. Dr. M. von Stackelberg on his 70th birthday. 相似文献
65.
T Hermann W Pfefferle C Baumann E Busker S Schaffer M Bott H Sahm N Dusch J Kalinowski A Pühler A K Bendt R Kr?mer A Burkovski 《Electrophoresis》2001,22(9):1712-1723
By the use of different Corynebacterium glutamicum strains more than 1.4 million tons of amino acids, mainly L-glutamate and L-lysine, are produced per year. A project was started recently to elucidate the complete DNA sequence of this bacterium. In this communication we describe an approach to analyze the C. glutamicum proteome, based on this genetic information, by a combination of two-dimensional (2-D) gel electrophoresis and protein identification via microsequencing or mass spectrometry. We used these techniques to resolve proteins of C. glutamicum with the aim to establish 2-D protein maps as a tool for basic microbiology and for strain improvement. In order to analyze the C. glutamicum proteome, methods were established to fractionate the C. glutamicum proteins according to functional entities, i.e., cytoplasm, membranes, and cell wall. Protein spots of the cytoplasmic and membrane fraction were identified by N-terminal sequencing, immunodetection, matrix assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS) and electrospray ionization-mass spectrometry (ESI-MS). Additionally, a protocol to analyze proteins secreted by C. glutamicum was established. Approximately 40 protein spots were observed on silver-stained 2-D gels, 12 of which were identified. 相似文献
66.
S.Y. Choi J. Kalinowski G. Moortgat–Pick P.M. Zerwas 《The European Physical Journal C - Particles and Fields》2001,22(3):563-579
Charginos and neutralinos in supersymmetric theories can be produced copiously at colliders and their properties can be measured with high accuracy. Consecutively to the chargino system, in which the SU(2)
gaugino parameter , the higgsino mass parameter and can be determined, the remaining fundamental supersymmetry parameter in the gaugino/higgsino sector of the minimal supersymmetric
extension of the Standard Model, the U(1) gaugino mass , can be analyzed in the neutralino system, including its modulus and its phase in CP–noninvariant theories. The CP properties
of the neutralino system are characterized by unitarity quadrangles. Analytical solutions for the neutralino mass eigenvalues
and the mixing matrix are presented for CP–noninvariant theories in general. They can be written in compact form for large
supersymmetric mass parameters. The closure of the neutralino and chargino systems can be studied by exploiting sum rules
for the pair-production processes in collisions. Thus the picture of the non–colored gaugino and higgsino complex in supersymmetric theories can comprehensively
be reconstructed in these experiments.
Received: 24 August 2001 / Published online: 21 November 2001 相似文献
67.
M. J. Pontes M. J. D. Dos Santos I. Abe H. J. Kalinowski M. T. M. R. Giraldi 《Fiber and Integrated Optics》2000,19(1):57-65
We report the results from the characterization and optimization of a stable erbium-doped fiber ring laser that uses two optical filters. The observed laser performance and the measured longitudinal mode patterns are presented. The influence of the combination of the two optical filters on the mode suppression is evaluated. We obtained the matched condition for operation of the optical filters that most improved the laser performance. An estimate of the relative intensity noise due to the introduction of the laser in a communication system is also presented. As a consequence of the mode suppression, a sharp laser linewidth narrowing is con firmed. 相似文献
68.
69.
Sivels Ciara B. McIntyre Justin I. Bowyer Theodore W. Kalinowski Martin B. Pozzi Sara A. 《Journal of Radioanalytical and Nuclear Chemistry》2017,314(2):829-841
Journal of Radioanalytical and Nuclear Chemistry - Developments in radioxenon monitoring since the implementation of the International Monitoring System are reviewed with emphasis on the most... 相似文献
70.
Ján Stariat Petra Kovaříková Radim Kučera Jiří Klimeš Danuta S. Kalinowski Des R. Richardson Raimo A. Ketola 《Analytical and bioanalytical chemistry》2013,405(5):1651-1661
Di-2-pyridylketone-4-cyclohexyl-4-methyl-3-thiosemicarbazone (DpC) is a promising analogue of the dipyridyl thiosemicarbazone class currently under development as a potential anti-cancer drug. In fact, this class of agents shows markedly greater anti-tumor activity and selectivity than the clinically investigated thiosemicarbazone, Triapine®. However, further development of DpC requires detailed data concerning its metabolism. Therefore, we focused on the identification of principal phase I and II metabolites of DpC in vitro. DpC was incubated with human liver microsomes/S9 fractions and the samples were analyzed using ultra-performance liquid chromatography (UPLCTM) with electrospray ionization quadrupole-time-of-flight (Q-TOF) mass spectrometry. An Acquity UPLC BEH C18 column was implemented with 2 mM ammonium acetate and acetonitrile in gradient mode as the mobile phase. The chemical structures of metabolites were proposed based on the accurate mass measurement of the protonated molecules as well as their main product ions. Ten phase I and two phase II metabolites were detected and structurally described. The metabolism of DpC occurred via oxidation of the thiocarbonyl group, hydroxylation and N-demethylation, as well as the combination of these reactions. Conjugates of DpC and the metabolite, M10, with glucuronic acid were also observed as phase II metabolites. Neither sulfate nor glutathione conjugates were detected. This study provides the first information about the chemical structure of the principal metabolites of DpC, which supports the development of this promising anti-cancer drug and provides vital data for further pharmacokinetic and in vivo metabolism studies. Figure
Proposed metabolic pathways of DpC 相似文献