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581.
Kinetic studies for hydroxylation of a series of alkanes (methane, ethane and propane) with intact cells and cell-free extracts
ofMethylosinus trichosporium OB3b were carried out.K
m values for alkane hydroxylation with cell-free extracts were lower than those with intact cells, suggesting that cytoplasm
plays an important role in the solubility of alkanes to increase their concentration. 相似文献
582.
K. Matsuzaki T. Uryu T. Kanai K. Hosonuma T. Matsubara H. Tachikawa M. Yamada und S. Okuzono 《Colloid and polymer science》1978,256(6):620
Ohne Zusammenfassung 相似文献
583.
584.
585.
We have previously developed a novel ultrasonic method, namely, the phased tracking method, for accurately tracking the movement of the heart wall based on both the phase and magnitude of the demodulated signals to determine the instantaneous position of an object. With this method, it is possible to accurately detect small-amplitude velocity signals of less than a few micrometers of the heart wall that are superimposed on the motion of the heart wall due to the heart beat. There are several remarkable pulsatile waves during one cardiac cycle in the resultant velocity signals, some of them being commonly obtained for both healthy subjects and patients. These pulsatile waves cannot be recognized in standard echocardiography M-mode images. In this paper, by focusing on one pulsatile wave that occurs around the end-systole, the physiological meaning of these is considered based on various in-vivo experiments. The pulsatile wave measured by this novel ultrasonic method will offer potential for a quantitative assessment of myocardial viability. 相似文献
586.
Kuo-Hui Wu Ryota Sakamoto Hiroaki Maeda Eunice Jia Han Phua Hiroshi Nishihara 《Molecules (Basel, Switzerland)》2021,26(14)
We developed an efficient and convenient electrochemical method to synthesize π-conjugated redox metal-complex linear polymer wires composed of azobenzene-bridged bis(terpyridine)metal (2-M, M = Fe, Ru) units covalently immobilized on glassy carbon (GC). Polymerization proceeds by electrochemical oxidation of bis(4′-(4-anilino)-2,2′:6′,2″-terpyridine)metal (1-M) in a water–acetonitrile–HClO4 solution, affording ultralong wires up to 7400 mers (corresponding to ca. 15 μm). Both 2-Fe and 2-Ru undergo reversible redox reactions, and their redox behaviors indicate remarkably fast redox conduction. Anisotropic hetero-metal-complex polymer wires with Fe and Ru centers are constructed via stepwise electropolymerization. The cyclic voltammograms of two hetero-metal-complex polymer wires, GC/[2-Fe]–[2-Ru] (3) and GC/[2-Ru]–[2-Fe] (4), show irreversible redox reactions with opposite electron transfer characteristics, indicating redox diodelike behavior. In short, the present electrochemical method is useful to synthesize polymer wire arrays and to integrate functional molecules on carbon. 相似文献
587.
We report on the first experimental evidence of the destructive and constructive interference of high harmonics generated in a mixed gas of He and Ne, which facilitates the coherent control of high harmonic generation. Theoretically, we develop an analytical model of high harmonic generation in mixed gases and succeed in reproducing the experimental results and deriving the optimization conditions for the process. The observed interference modulation is attributed to the difference between the phases of the intrinsically chirped harmonic pulses from He and Ne, which leads to a novel method for broadband measurement of the harmonic phases and for observing the underlying attosecond electron dynamics. 相似文献
588.
Nishiyama Y Kaneda M Asaoka S Saito R Mori T Wada T Inoue Y 《The journal of physical chemistry. A》2007,111(51):13432-13440
Enantiodifferentiating anti-Markovnikov photoaddition of alcohol (methanol, ethanol, 2-propanol, and tert-butanol) to aromatic alkene (1,1-diphenylpropene and 1,1-diphenyl-1-butene), sensitized by optically active alkyl and saccharide naphthalene(di)carboxylates, was investigated in supercritical carbon dioxide at varying pressures to elucidate the effects of clustering on photosensitization and enantiodifferentiation behavior, in particular on the product's enantiomeric excess (ee). For all the alkene/alcohol/chiral sensitizer combinations examined, a sudden change in the product's ee was consistently observed near the critical density, which is attributable to the critical pressure dependence of clustering around the intervening exciplex intermediate. 相似文献
589.
Chatake T Shibayama N Park SY Kurihara K Tamada T Tanaka I Niimura N Kuroki R Morimoto Y 《Journal of the American Chemical Society》2007,129(48):14840-14841
The protonation states of buried histidine residues in human deoxyhemoglobin were unambiguously identified by using a neutron crystallographic technique. Unexpectedly, the neutron structure reveals that both the alpha- and beta-distal histidines (Hisalpha58 and Hisbeta63) adopt a positively charged, fully (doubly) protonated form, suggesting their contribution to the Bohr effect. In addition, the neutron data provide an accurate picture of the alpha1beta1 hydrogen-bonding network and allow us to observe unambiguously the nature of the intradimeric interactions at an atomic level. 相似文献
590.
Iimori T Iwahashi T Kanai K Seki K Sung J Kim D Hamaguchi HO Ouchi Y 《The journal of physical chemistry. B》2007,111(18):4860-4866
The air/liquid interface of 1-alkyl-3-methylimidazolium tetrafluoroborates with the general formula [C(n)mim]BF(4) (n = 4-11) was studied using infrared-visible sum frequency generation (SFG) vibrational spectroscopy. The probability of the gauche defect per CH2-CH2 bond in the alkyl chain decreases as the number of carbon atoms in the alkyl chain increases. This observation suggests that the interaction between the alkyl chains is enhanced as the alkyl chain length becomes longer. The frequencies of the C-H stretching vibrational modes observed in the SFG spectra are higher than those of the corresponding peak positions observed in the infrared spectra of the bulk liquids. This shift is consistent with a structure in which the alkyl chain protrudes from the bulk liquid into the air. A local structure, which originates from the intermolecular interaction between the ionic liquid molecules, is proposed to explain these observations. 相似文献