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131.
Hartwig Möller Nikolaus Seiler Gottfried Werner 《Analytical and bioanalytical chemistry》1968,243(1):126-129
Some experiences are given with a measuring device for the determination of the specific radioactivity of 14C-labelled brain amino-acids. The apparatus consists of an automatic amino-acid analyzer combined with a flow cell filled with anthracene. The reproducibility of the method is ±5% to ±1% m.e. in the range of 1×10?3 μCi to 5×10?2 μCi. A quantitative determination of 3×10?4 μCi/ml eluant is still possible. 相似文献
132.
Gottfried Köthe 《Mathematische Annalen》1968,178(1):1-3
Ohne ZusammenfassungHeinrich Behnke zum 70. Geburtstag 相似文献
133.
Ohne ZusammenfassungHerrnHelmut Grunsky zum 60. Geburtstag am 11. Juli 1964 gewidmet 相似文献
134.
135.
Gottfried Spelsberg-Korspeter 《Journal of sound and vibration》2010,329(23):4829-4840
Self-excited vibrations are a severe problem in many technical applications. In many cases they are caused by friction as for example in disk and drum brakes, clutches, saws and paper calenders. The goal to suppress self-excited vibrations can be reached by active and passive techniques, the latter ones being preferable due to the lower costs. Among design engineers it is known that breaking the symmetries of structures is sometimes helpful to avoid self-excited vibrations. This has been verified from an analytical point of view in a recent paper. The goal of the present paper is to use this analytical insight for a systematic structural optimization of rotors in frictional contact. The first system investigated is a simple discrete model of a rotor in frictional contact. As a continuous example a rotating beam in frictional contact is considered and optimized with respect to its bending stiffness. Finally a brake disk is optimized giving some attention to the feasibility of the modifications for the production process. 相似文献
136.
Abstract Fluorescence correlation spectroscopy (FCS) is an important biophysical technique. FCS is currently being used in many areas of biology to solve several scientific problems. Its properties such as detection at the single molecular level, higher sensitivity, and use of lower sample volume make FCS a promising molecular diagnostic tool. The promising applications of FCS extend from DNA kinetics/dynamics studies to the comprehensive understanding of receptor–ligand interactions. In this article, we review various promising biological applications of FCS. 相似文献
137.
Reaction of the vicinal diols of steroids1, 5, 7, 10, 13, and16 with TPP/DEAD yields both regio-and stereospecifically the oxosteroids2, 6, 8, 11, 14, and15 by displacement of an axial hydrogen and extrusion ofTPPO besides the cholest-4-en-6-ols9 and12 and the cyclic carbonate3. 16, 17-androstandiol16 gives only the cyclic carbonate17. The different structures of the carbohydrates withcis-diol arrangement19 and21 lead exclusively to cyclic carbonates20 and22 in moderate yields. Treatment of1 with TPP/DEAD/HN3 affords 3-azido-2-hydroxycholestane4 in addition to the above mentioned2. 相似文献
138.
139.
Franz Heresch Guenter Allmaier Gottfried Heinisch 《Journal of heterocyclic chemistry》1981,18(2):255-258
The electron impact mass spectrometric fragmentation of trans-3- and trans-4-styrylpyridazine is reported in detail, including a comparison with other aza-stilbenes. With regard to a distinction between the two isomeric styrylpyridazines, the intensity ratio of the M+ and [M-1]+ ions, the general degree of fragmentation and the elimination pathways of nitrogen proved to be most characteristic. 相似文献
140.
Jörn Müller Helmuth Menig Gottfried Huttner Albin Frank 《Journal of organometallic chemistry》1980,185(2):251-263
The complexes [Ir(COD)(η5-C7H9)] and [Ir(COD)(η5-C8H11)] are obtained by the isoprophyl Grignard synthesis of [Ir(COD)Cl]2 (COD = η4-1,5-cyclooctadiene) in the presence of cycloheptatriene, and cyclooctatriene, respectively. The later reaction yields [IrH(COD)(δ4-1,3,6-C8H10)] as a by-product which, in contrast to other [IrH(η4-cyclodiene)2] complexes, does not show H-addition-elimination equilibria. Reduction of [Ir(1,3-C7H10)2Cl] with C2H5OH/Na2CO3 yields [Ir(η4-1,3-C7H10)](η5-C7H9)] which was characterized by X-ray analysis. [Ir(COD)Cl]2 reacts with Na2C8H8, and after hydrolysis unstable [Ir(COD)(η5-C8H9)] is formed which by protonation with HPF6 is converted into the [Ir(COD)(η6-1,3,5-C8H10)]+ cation. All these compounds are fluxional in solution. 相似文献