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101.
102.
Renewable energy is regarded as a clean energy source but has some problems, one of which is intermittency. To reduce this, the time-delay of hydrogen production by photosynthetic bacteria can be effective. In this study, we qualitatively evaluated the time-delay of hydrogen production by photosynthetic bacteria under various irradiation conditions, and we also quantitatively evaluated it by fitting the experimental data and the hydrogen production model with a genetic algorithm. As a result of model fitting, we found that the relationship between the lengths of the optimized time-delay of hydrogen production by photosynthetic bacteria and the amount of light irradiation is linear. And we also found that the time-delay of hydrogen production by photosynthetic bacteria had an upper limit under low light intensity. We have suggested the existence of an energy store mechanism in photosynthetic bacteria.  相似文献   
103.
A simple and accurate method for the estimation of ultrasonic transducer fields is developed. In the method, the angular spectrum is employed to evaluate the three-dimensional propagation from a measured plane to an arbitrary parallel plane. The implementation uses a discrete convolution that is described in detail. Relative to conventional spatial-frequency representations, the implementation of the angular spectrum method in this paper has the advantage of being free from artifacts, enabling sample spacing to be greater than one half wavelength, using memory efficiently, and interpolating the measured data. The loosened sampling requirement and natural interpolation of the method permit efficient reconstruction of the full three-dimensional acoustic field from a coarse sound pressure measurement on single plane.  相似文献   
104.
We examined the formation of complexes between terbium ion (Tb3+) and carbohydrates labeled with aminobenzene compounds. Of the examined compounds, carbohydrates labeled with 4-aminosalicylic acid showed intense fluorescence with Tb3+ in the presence of cetylpyridinium chloride at pH 6.0. Calibration curves for maltose derivative showed good linearity between 5 pmol and at least 600 pmol, with good reproducibility. We applied the proposed technique to binding studies between manno-oligosaccharides and Concanavalin A.  相似文献   
105.
Dithienylethenes with a novel photochromic performance   总被引:2,自引:0,他引:2  
Dithienylethenes with low decoloration quantum yields and thermal reversibility at high temperature above 100 degrees C were prepared. Introduction of bulky alkoxy substituents at 2- and 2'-positions of the thiophene rings strongly suppressed the cycloreversion quantum yields. The quantum yields were lower than 10(-3), and the photogenerated color remained stable enough under room light. On the other hand, the bulky alkoxy substituent decreased the thermal stability of the colored closed-ring isomers at high temperature. The color of the dithienylethene with cyclohexyloxy substituents faded out in less than 1 min at 160 degrees C.  相似文献   
106.
[reaction: see text]. Rhodium complex-catalyzed carbonylative alkene-alkyne coupling proceeds using aldehydes as a CO source. Cinnamaldehyde is the best CO donor, and various cyclopentenones were provided in high isolated yields by a solvent-free system.  相似文献   
107.
In e(+)e(-) collisions using the CLEO detector, we have studied the decay of the D0 to the final state K(0)(S)pi(+)pi(-) with the initial flavor of the D0 tagged by the decay D(*+)-->D0pi(+). We use the Dalitz technique to measure the resonant substructure in this final state and clearly observe ten different contributions by fitting for their amplitudes and relative phases. We observe a K(*)(892)(+)pi(-) component which arises from doubly Cabibbo suppressed decays or D0-D0; mixing.  相似文献   
108.
We report on a search for charmless hadronic B decays to the three-body final states K(0)(S)h(+)pi(-), K(+)h(-)pi(0), K(0)(S)h(+)pi(0) (h(+/-) denotes a charged pion or kaon), and their charge conjugates, using 13.5 fb(-1) of integrated luminosity produced near sqrt[s]=10.6 GeV, and collected with the CLEO detector. We observe the decay B-->K0pi(+)pi(-) with a branching fraction (50(+10)(-9)(stat.)+/-7(syst.))x10(-6) and the decay B-->K(*+)(892)pi(-) with a branching fraction (16(+6)(-5)(stat.)+/-2(syst.))x10(-6).  相似文献   
109.
[formula: see text] A novel approach for the preparation of symmetrical (chlorin-chlorin), and unsymmetrical (chlorin-porphyrin) dimers joined with carbon-carbon linkages as models to study the "intramolecular" charge transfer is discussed.  相似文献   
110.
The method of projection operators, which plays an important role in the field of nonequilibrium statistical mechanics, has been established with the use of the Liouville-von Neumann equation for a density matrix to eliminate irrelevant information from a whole system. We formulate a unified and general projection operator method for dynamical variables. The main features of our formalism parallel those for the Liouville-von Neumann equation. (1) Two types of basic equations, time-convolution and time-convolutionless decompositions, are systematically obtained without specifying a projection operator. (2) Expansion formulas for both decompositions are also obtained. (3) Problems incorporating a time-dependent Liouville operator can be flexibly treated. We apply the formulas to problems in random frequency modulation and low field resonance. In conclusion, our formalism yields a more direct and easier means of determining the average time evolution of an operator than the one for the Liouville-von Neumann equation.  相似文献   
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