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GeMe2H2 reacts under mild conditions with [{Co2(CO)7}2Ge] to replace one bridging CO and give [Co4(CO)13Ge(GeMe2)]. GeH4 similarly yields a trace of [Co6(CO)20Ge2], which may be made in high yield from [Co2(CO)8] and Ge2H6 or Me2Si(GeH3)2. Spectroscopic evidence suggests structures of linked GeCo2 triangles. 相似文献
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Abstract— The effect of hydroxylamine on the phototactic activity of Chlamydomonas reinhardtii was investigated. The following results were obtained: (1) wild type cells, irradiated for 10 min with green light immediately after addition of 1 mM hydroxylamine, showed a 20 min transient loss of phototactic activity, (2) irradiation of cells, preincubated in the dark with 4 mM. hydroxylamine for 30 min, diminished the phototactic sensitivity permanently by more than 100-fold without loss of cell motility. (3) The phototactic sensitivity completely recovered within 3(1 min of the removal of hydroxylamin from carotenoid-containing cells or from carotenoid-negative cells upon addition of 11- cis or all- trans retinal. Our explanation is bleaching of rhodopsin by more than 99% and reconstitution by de novo synthesized or by added retinal. 相似文献
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J. A. Blanc C. A. Stone C. A. D'Urso T. L. M. Langlands J. R. Crooks D. E. Foster 《Journal of Radioanalytical and Nuclear Chemistry》1997,219(2):251-255
We are developing electronic laboratories to help introduce students to nuclear science. An electronic laboratory is a collection of computer simulations of nuclear science experiments. Each program allows students to set experimental parameters, collect data, and analyze results. Experiments can easily be repeated because the computer can compress time. Electronic laboratories are useful for schools with existing nuclear science programs because they can prepare students for actual laboratory work. They are also useful for schools without specialized facilities, since they give students an empirical understanding of nuclear science but do not require specialized equipment. We present three electronic experiments. 相似文献
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Six bands in the 0-v″ progression and three bands in the 1-v″ progression of the A2Πi → X2Πr visible system of SO+ have been recorded photoelectrically and rotationally assigned. Molecular constants for v′ = 0 and 1 in the A state and for v″ = 4–9 in the X state have been obtained using direct fitting and merging techniques. 相似文献
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