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71.
Tatsuo Iwasa Fumio Tokunaga Tôru Yoshizawa Thomas G. Ebrey 《Photochemistry and photobiology》1980,31(1):83-85
Abstract— Quantum efficiencies for photoconversion of bacteriorhodopsin (trans-bR) to a bathochromic product (batho-bRt ) and its photoreversion in purple membrane at 77 and 9 K were investigated with low temperature spectrophotometry. The kinetics of the photoconversion and its photoreversion cannot be expressed by a single exponential curve. The photoconversions at 77 and 9 K showed the same slope in the early stage. The kinetics of the photoreversions were identical at the two temperatures. These results indicate that the quantum efficiencies for the conversion of trans-bR to batho-bRt or for its photoreversion are identical at the two temperatures.
The fact that the photoreversion cannot be expressed by a single exponential curve suggests the existence of several conformational states of batho-bRt due to the trimer structure of the purple membrane. 相似文献
The fact that the photoreversion cannot be expressed by a single exponential curve suggests the existence of several conformational states of batho-bR
72.
73.
Kenji Yajima 《Communications in Mathematical Physics》1980,75(2):153-178
Scattering theory for time dependent HamiltonianH(t)=?(1/2) Δ+ΣV j (x?q j (t)) is discussed. The existence, asymptotic orthogonality and the asymptotic completeness of the multi-channel wave operators are obtained under the conditions that the potentials are short range: |V j (x)|≦C j (1+|x|)?2?ε, roughly spoken; and the trajectoriesq j (t) are straight lines at remote past and far future, and |q j (t)?q k (t)| → ∞ ast → ± ∞ (j≠k). 相似文献
74.
A simple noncollinear SHG autocorrelator for monitoring the time behavior of single subpicosecond laser pulses is described. A new CCD image-line sensor with high sensitivity in the UV range is used to measure the second-harmonic (SH) spatial distribution which gives information on the duration of the fundamental light pulses. An input energy of only 10 μJ is enough to obtain the SH spatial beam patterns in this highly sensitive autocorrelation system. 相似文献
75.
We study smoothing properties for time-dependent Schrödinger equations , , with potentials which satisfy V(x)=O(|x|m) at infinity, m?2. We show that the solution u(t,x) is 1/m times differentiable with respect to x at almost all , and explain that this is the result of the fact that the sojourn time of classical particles with energy λ in arbitrary compact set is less than CTλ−1/m during [0,T] when λ is very large. We also show Strichartz's inequality with derivative loss for such potentials and give its application to nonlinear Schrödinger equations. 相似文献
76.
The observation of slow-wave sustained (SW) discharge in a whistler- or helicon-wave range of frequency is made using high-frequency and very-high-frequency bands of rf. The SW discharge occurs at an extremely low rf power and plasma density, which are lower than a capacitive-coupling discharge region. 相似文献
77.
Nakazawa J Yajima J Usui T Ueki M Takatsuki A Imoto M Toyoshima YY Osada H 《Chemistry & biology》2003,10(2):131-137
To reveal the mechanism of mitosis, the development of M phase-specific inhibitors is an important strategy. We have been screening microbial products to find specific M phase inhibitors that do not directly target tubulins, and rediscovered terpendole E (TerE) as a novel Eg5 inhibitor. TerE did not affect microtubule integrity in interphase, but induced formation of a monoastral spindle in M phase. TerE inhibited both motor and microtubule-stimulated ATPase activities of human Eg5, but did not affect conventional kinesin from either Drosophila or bovine brain. Although terpendoles have been reported as inhibitors of acyl-CoA:cholesterol O-acyltransferase (ACAT), the Eg5 inhibitory activity of TerE was independent of ACAT inhibition. Taken together, we demonstrate that TerE is a novel Eg5 inhibitor isolated from a fungal strain. 相似文献
78.
Yajima T Wakabayashi N Uchida H Watanabe M 《Chemical communications (Cambridge, England)》2003,(7):828-829
Adsorbed water molecules which promote the methanol oxidation reaction (MOR) at Pt-Ru alloy electrode are clearly detected by in-situ FTIR spectroscopy with the attenuated total reflection configuration, which directly supports the "bi-functional mechanism" for the MOR. 相似文献
79.
Control of the efficiency of photoisomerization by oxygen was demonstrated for 1,3,5-tristyrylbenzene dendrimers 1-3; the large dendrons do not significantly affect the photochemistry itself due to volume-conserving isomerization mechanisms but may affect the mobility of the molecules. 相似文献
80.
Yoshiaki Tanaka Tatsuo Fujii Yoshihiro Kusano Yasunori Ikeda 《Solid State Communications》2007,141(3):122-126
Single-phases of Pb-substituted Bi-Ca-Co-O misfit-layer cobaltites with various Pb concentrations have been synthesized and the Pb-substitution effects on the structural, electrical and magnetic properties have been systematically investigated. Powder X-ray diffraction analysis showed that the single-phases of Bi1.8−x/2PbxCa2Co2Oz were obtained up to x=0.6-0.7 under the optimized synthesis conditions. The lattice parameters of Bi1.8−x/2PbxCa2Co2Oz continuously changed with increasing Pb concentration. The electron diffraction analysis suggested that the structure consisted of two different sublattices with a rock salt structure (RS) and a hexagonal CdI2 structure (H), respectively, without modulation. In combined with the chemical composition analysis, the chemical formulas of the x=0 and x=0.6 samples were determined approximately as [Bi1.74Co0.31Ca2.01O4]RS[CoO2]1.69 and [Bi1.47Pb0.38Co0.29Ca1.98O4]RS[CoO2]1.71, respectively. The electrical resistivity became more metallic with increasing the Pb concentration up to x=0.6. Moreover, the Pb-substitution simultaneously increased the antiferromagnetic Weiss temperatures and decreased the effective magnetic moments of the Co ions. 相似文献