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211.
M. Hata 《Journal d'Analyse Mathématique》1994,64(1):347-347
The online version of the original article can be found at 相似文献
212.
Fang Cao Ryuji Hata Pengxiang Zhu Shoichiro Takeda Tadashi Yoshida Nobuhiro Hakuba Masahiro Sakanaka Kiyofumi Gyo 《BMC neuroscience》2010,11(1):115
Background
Because of the lack of reproducible brainstem ischemia models in rodents, the temporal profile of ischemic lesions in the brainstem after transient brainstem ischemia has not been evaluated intensively. Previously, we produced a reproducible brainstem ischemia model of Mongolian gerbils. Here, we showed the temporal profile of ischemic lesions after transient brainstem ischemia. 相似文献213.
214.
Inside Cover: Molecularly Designed Nanoparticles by Dispersion of Self‐Assembled Organosiloxane‐Based Mesophases (Angew. Chem. Int. Ed. 35/2014)
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215.
Synthesis of single- and double-walled carbon nanotube forests on conducting metal foils 总被引:2,自引:0,他引:2
Hiraoka T Yamada T Hata K Futaba DN Kurachi H Uemura S Yumura M Iijima S 《Journal of the American Chemical Society》2006,128(41):13338-13339
Here, we report a highly efficient growth of single-walled carbon nanotubes (SWNTs) and double-walled carbon nanotubes (DWNTs) on conducting metal foils. We found that foils made of Ni-based alloys with Cr or Fe serve as excellent substrates for SWNT (DWNT) synthesis. In significant contrast, a CNT grown on Ni, Fe foils contains a significant ratio of MWNTs. This result opens up an economical route for the mass production of SWNT (DWNT) forests and also enables the straightforward integration of CNTs into nanoelectronic devices, such as field emission displays. 相似文献
216.
The NM-gamma CNDO/S program previously developed by our group was modified by the introduction of a new one-center electron repulsion integral gamma(AA)(new) approximation, namely, the gamma(AA)(new)-CNDO/S method. The value of this gamma(AA)(new) was evaluated according to the product values of the coefficient C with the gamma(AA) value proposed in our previous paper. This method using a new gamma(AA) was also found to improve the two-center electron repulsion integral gamma(AB) value with respect to the chemical softness proposed by Nishimoto and co-workers, together with the difference between HOMO and LUMO orbital energies. The results calculated by the present improved gamma(AA)(new)-CNDO/S method demonstrated that not only the calculated absorption maxima wavelengths and ionization potentials, but also the order and the assignment of orbitals coincided very well with those based on the results of experiments investigating a variety of polyenes, cyanynes, and polycyclic aromatic hydrocarbons. 相似文献
217.
A hydrophilic polymer, poly(vinylpyrrolidone) (PVP), was employed for suppressing the electroosmotic flow (EOF). A capillary was filled with aqueous PVP solution for coating the capillary wall with PVP; the PVP solution was then replaced by a migration buffer solution containing no PVP. Three types of PVP with different molecular weights were examined. The EOF was suppressed more effectively as the molecular weight of PVP increased. The EOF in the coated capillary was approximately 10-fold smaller than that of a bare capillary and was constant in the pH range of 6-8. The suppressed EOF was stable even when no PVP was added to the migration buffer. However, the EOF increased significantly when sodium dodecyl sulfate was added into the migration buffer. The method was applied for determining the electrophoretic mobilities of inorganic anions that have negative electrophoretic mobilities larger than the electroosmotic mobility of the bare capillary. A novel method for determining the electrophoretic mobilities was proposed based on the linear relationship between electric current and electrophoretic mobility. The electrophoretic mobility was proportional to the electric current. Therefore, the intercept of the regression equation represents the electrophoretic mobility at room temperature. The electrophoretic mobilities were in good agreement with the absolute electrophoretic mobilities. 相似文献
218.
The potential energy change during the M --> N process in bacteriorhodopsin has been evaluated by ab initio quantum chemical and advanced quantum chemical calculations following molecular dynamics (MD) simulations. Many previous experimental studies have suggested that the proton transfer from Asp96 to the Schiff base occurs under the following two conditions: (1) the hydrogen bond between Thr46 and Asp96 breaks and Thr46 is detached from Asp96 and (2) a stable chain of four water molecules spans an area from Asp96 --> Schiff base. In this work, we successfully reproduced the proton-transfer process occurring under these two conditions by molecular dynamics and quantum chemical calculations. The quantum chemical computation revealed that the proton transfer from Asp96 to Shiff base occurs in two-step reactions via an intermediate in which an H(3)O(+) appears around Ala215. The activation energy for the proton transfer in the first reaction was calculated to be 9.7 kcal/mol, which enables fast and efficient proton pump action. Further QM/MM (quantum mechanical/molecular mechanical) and FMO (fragment molecular orbital) calculations revealed that the potential energy change during the proton transfer is tightly regulated by the composition and the geometry of the surrounding amino acid residues of bacteriorhodopsin. Here, we report in detail the Asp96 --> Schiff base proton translocation mechanism of bacteriorhodopsin. Additionally, we discuss the effectiveness of combining quantum chemical calculations with truncated cluster models followed by advanced quantum chemical calculations applied to a whole protein to elucidate its reaction mechanism. 相似文献
219.
220.
Hamamoto H Shiozaki Y Nambu H Hata K Tohma H Kita Y 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(20):4977-4982
The non-phenolic coupling reaction of benzyltetrahydroisoquinolines (laudanosine derivatives) by using a hypervalent iodine(III) reagent is described. In general, chemical oxidation of laudanosine gives glaucine. In contrast to general chemical oxidizing reagent systems, the novel use of reagent combination of phenyliodine bis(trifluoroacetate) (PIFA), and heteropoly acid (HPA) afforded morphinandienone alkaloids in excellent yields. In order to achieve the coupling reaction with simple reaction procedure, the use of HPA supported on silica gel instead of HPA was demonstrated and sufficient yield was exerted again. The present reagent system, PIFA/HPA, was also applied to the oxidation of other non-phenolic benzyltetrahydroisoquinolines and the high yield conversion to morphinandienones was accomplished. 相似文献