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91.
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
96.
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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On a recent attempt to define the interpretation basis in the many worlds interpretation of quantum mechanics 总被引:1,自引:0,他引:1
David Deutsch's 1985 algorithm to determine the preferred product structure and basis in the many worlds interpretation is examined. His heuristic argument for the conditions appearing in the algorithm is found wanting. The question of the existence and uniqueness of a final solution to his algorithm is discussed. The algorithm is shown to be inadequate to account for certain types of measurement which are, at least in principle, possible. 相似文献
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