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991.
We present a practical method for calculating the local gravitational self-force (often called "radiation-reaction force") for a pointlike particle orbiting a Schwarzschild black hole. This is an implementation of the method of mode-sum regularization, in which one first calculates the (finite) contribution to the force due to each individual multipole mode of the perturbation, and then applies a certain regularization procedure to the mode sum. Here we give the values of all the "regularization parameters" required for implementing this regularization procedure, for any geodesic orbit in Schwarzschild spacetime. 相似文献
992.
Racemic indanofan [(+/-)-1] was efficiently converted to enantiopure (S)-indanofan [(S)-1] by a combination of enzymatic resolution and chemical inversion techniques. An additional important technique is the use of an o-xylene complex of a hemiketal (S)-3c as a precursor, which can be quantitatively converted to (S)-indanofan and easily purified by recrystallization from o-xylene. 相似文献
993.
A flow type microbial biosensor for direct measurement of trichloroethylene (TCE) was developed. The unique features of this novel microbial sensor were the use of the TCE degrading bacterium Pseudomonas aeruginosa JI104, the electrical detection of the chloride ion released by microbial degradation, and flow cell made of glass. Glass cell was used in order to suppress adsorption of TCE and made a closed reaction cell. Vaporization of TCE during the measurement was prevented using closed flow cell. The performance of the sensor was evaluated from following aspects; such as pH of the carrier solution, amount of the immobilized microbe, flow rate and injection volume. The sensor signals were linearly proportional to the concentration of TCE in the range from 0.03 to 2 mgl(-1), which is suitable for the determination of suspected samples to be drinkable water or not. The sensor performance was checked on the real sample, and this system showed good response in ground water, indicating its applicability for the on line monitoring at TCE contaminated areas or hazardous sites. 相似文献
994.
Yamashita F Fujiwara S Hashida M 《Journal of chemical information and computer sciences》2002,42(2):408-413
Caco-2 cell monolayers grown on a filter support are the most widely used systems for predicting intestinal absorption. However, inter- and intralaboratory variability in Caco-2 permeability makes it difficult to analyze any QSPR relationship for a large number of compounds. We proposed the "latent membrane permeability" concept, assuming that all Caco-2 permeability data sets share a hidden, common relationship between their membrane permeability and physicochemical properties. An iterative calculation method was developed to handle this conceptual approach and applied to the analysis of Caco-2 permeability data sets from different sources. A thorough statistical analysis revealed that the "latent membrane permeability" concept be reasonable. 相似文献
995.
Iwaura R Ohnishi-Kameyama M Yoshida M Shimizu T 《Chemical communications (Cambridge, England)》2002,(22):2658-2659
Complementary base paired complex formation of a thymidine-appended bolaamphiphile with adenosine derivatives was able to be detected with high resolution and high sensitivity in aqueous solutions by electrospray ionization-Fourier-transform ion cyclotron resonance mass (ESI-FTICR MS) spectrometry. 相似文献
996.
997.
[reaction: see text] The inverse electron-demand 1,3-dipolar cycloaddition of nitrones with ynolates, followed by quenching with t-BuOH, produced substituted 5-isoxazolidinones with good trans-selectivity. These products were easily converted into beta-amino acids. 相似文献
998.
Yamada K Sasaki K Harada Y Isobe R Higuchi R 《Chemical & pharmaceutical bulletin》2002,50(11):1467-1470
Ten glucocerebrosides, HPC-3-A-HPC-3-J, have been isolated from their obtained parent glucocerebroside molecular species HPC-3, together with other glucocerebroside molecular species HPC-1 and HPC-2, from the less polar lipid fraction of a chloroform/methanol extract of the sea cucumber Holothuria pervicax. The structures of these glucocerebrosides have been determined on the basis of chemical and spectroscopic evidence. Reversed-phase HPLC, including a recycling system, was effective in isolating these glucocerebrosides, revealing a very close resemblance in structure, though the problem due to regio-isomers remains. 相似文献
999.
Takeuchi Y Azuma K Abe H Sasaki K Harayama T 《Chemical & pharmaceutical bulletin》2002,50(7):1011-1012
The stereo structure of piperidine lactone (3), an intermediate of the antimalarial agent febrifugine ((+)-1) prepared by a synthetic method, was re-revised to the cis-form from the trans-form. 相似文献
1000.