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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   
63.
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.
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   
64.
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   
65.
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   
66.
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   
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Higgs particles can be radiated off heavy top quarks which will be produced copiously in high energye + e ? colliders. This process can be used to measure the Higgs-top quark coupling. We present the cross section for the production of Higgs bosons in the Standard Model. In addition we have studied the production of neutral and charged Higgs particles in association with heavy fermions in the Minimal Supersymmetric Standard Model.  相似文献   
70.
Solid-state transitions in crystalline tetracene have been investigated by Raman spectroscopy and by anisotropy of the effect of a magnetic field on its prompt fluorescence. Discontinuous changes in the temperature dependence of Raman lattice modes and new phonon lines occur near 182 and 144 K, signifying the occurrence of two phase transitions. The magnetic anisotropy effect shows a gradual change with temperature, suggesting the transition at 182 K is preceded by a continuous rotation of the intermolecular plane.  相似文献   
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