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81.
Noriko Mizoguchi 《Journal of Functional Analysis》2005,220(1):214-227
The present paper is concerned with a Cauchy problem for a semilinear heat equation
(P) 相似文献
82.
Macías-Ruvalcaba NA Okumura N Evans DH 《The journal of physical chemistry. B》2006,110(43):22043-22047
The electrochemical reduction of 3,5-di-tert-butyl-1,2-benzoquinone, 1, has been studied in acetonitrile with added 2,2,2-trifluoroethanol, 2. At low concentrations of 2 the reaction proceeds by the following pathway: reduction of the quinone (Q) to its anion radical (Q*-) followed by complexation of the anion radical with 2 (HA) and the further reduction of the hydrogen-bonded complex (Q*- (HA)) to form HQ- and A-. The latter reaction is a concerted proton and electron- transfer reaction (CPET). At higher concentrations of 2, the pathway changes. The first steps remain the same, but now Q*- (HA) is reduced to HQ- via a disproportionation reaction with Q*- along with proton transfer from HA to Q*- to form HQ* which is reduced to HQ-. The only mechanism that could be found which would account for all of the data involves proton transfer to Q*- occurring within a higher complex, Q*-(HA)3. 相似文献
83.
84.
Noriko Mizoguchi 《Journal of Differential Equations》2006,227(2):652-669
We consider a Cauchy problem for a semilinear heat equation
(P) 相似文献
85.
86.
Evandro A. de Morais Luis V.A. Scalvi Alberto A. Cavalheiro Américo Tabata José Brás B. Oliveira 《Journal of Non》2008,354(42-44):4840-4845
Some very relevant optical, electrical, and structural properties of SnO2 doped with rare-earth ions Er3+ and Eu3+ are presented. Films are produced by the sol–gel-dip coating process, and may be described as a combination of nanoscopic dimension crystallites (about 3–10 nm) with their respective intergrain potential barriers. The Er3+ and Eu3+ ions are expected to act as acceptors in SnO2, which is a natural n-type conductor, inducing a high degree of charge compensation. Electron trapping and emission spectra data are presented and are rather distinct, depending on the location of the rare-earth impurity. This behavior allows the identification of two distinct centers: located either in the SnO2 lattice or segregated at the particles surface. Based on a model for thermally activated cross-section defects, the difference between the capture energy of the photo-excited electron and the intergrain potential barrier is evaluated, leading to distinct values for high and low symmetry sites. A higher distortion in the lattice of undoped SnO2 and SnO2:Eu (1 at.%) was evaluated from Rietveld refinements of X-ray diffraction data. This was confirmed by Raman spectra, which are associated with the particles size and disorder. By comparing the samples with the same doping concentration, it was found that this disorder is higher in Eu-doped SnO2 than in Er-doped SnO2, which is in agreement with a higher energy for the lattice relaxation in the trapping process by Eu3+ centers. 相似文献
87.
Kanna Adachi Tomoshi Yamada Hayate Ishizuka Mana Oki Shunsuke Tsunogae Noriko Shimada Osamu Chiba Tatsuya Orihara Prof. Dr. Masafumi Hidaka Prof. Dr. Takatsugu Hirokawa Dr. Minami Odagi Prof. Dr. Keiichi Konoki Prof. Dr. Mari Yotsu-Yamashita Prof. Dr. Kazuo Nagasawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(9):2025-2033
A novel series of C12-keto-type saxitoxin (STX) derivatives bearing an unusual nonhydrated form of the ketone at C12 has been synthesized, and their NaV-inhibitory activity has been evaluated in a cell-based assay as well as whole-cell patch-clamp recording. Among these compounds, 11-benzylidene STX ( 3 a ) showed potent inhibitory activity against neuroblastoma Neuro 2A in both cell-based and electrophysiological analyses, with EC50 and IC50 values of 8.5 and 30.7 nm , respectively. Interestingly, the compound showed potent inhibitory activity against tetrodotoxin-resistant subtype of NaV1.5, with an IC50 value of 94.1 nm . Derivatives 3 a – d and 3 f showed low recovery rates from NaV1.2 subtype (ca 45–79 %) compared to natural dcSTX ( 2 ), strongly suggesting an irreversible mode of interaction. We propose an interaction model for the C12-keto derivatives with NaV in which the enone moiety in the STX derivatives 3 works as Michael acceptor for the carboxylate of Asp1717. 相似文献
88.
Noriko Shimizu Tomoji Ozeki Hideyasu Shikama Tsuneji Sano Masahiro Sadakane 《Journal of Cluster Science》2014,25(3):755-770
We found that three isomers of mono-Ru substituted Keggin-type germanotungstate with a dmso ligand, [GeW11O39RuII(dmso)]6?, could be formed by a reaction of α-Keggin-type mono-lacunary germanotungstate, [α-GeW11O39]8?, with Ru(dmso)4Cl2. The main isomer is an α-isomer, and the others are β2-isomer and β3-isomer, which were confirmed by 1H NMR, cyclic voltammetry, IR, and single crystal X-ray structure analysis. 相似文献
89.
Biological assays at the single molecule level are crucial to fundamental studies of DNA-protein mechanisms. In order to cater
for high throughput applications, one area of immense research potential is single-molecule bioassays where miniaturized devices
are developed to perform rapid and effective biological reactions and analyses. With the success of various emerging technologies
for engineering miniaturized structures down to the nanoscale level, supported by specialized equipment for detection, many
investigations in the field of life science that were once thought impossible can now be actively explored. In this review,
the significance of downscaling to the single-molecule level is firstly presented in selected examples, with the focus placed
on restriction enzyme assays. To determine the effectiveness of single-molecule restriction enzyme reactions, simple and direct
analytical methods based on DNA stretching have often been reliably employed. DNA stretching can be realized based on a number
of working principles related to the physical forces exerted on the DNA samples. We then discuss two examples of a nanochannel
system and a microchamber system where single-molecule restriction enzyme digestion and DNA stretching have been integrated,
which possess prospective capabilities of developing into highly sensitive and high-throughput restriction enzyme assays.
Finally, we take a brief look at the general trends in technological development in this field by comparing the advantages
and disadvantages of performing assays at bulk, microscale and single-molecule levels.
Figure Minaturization of Restriction Enzyme Assays and DNA Stretching 相似文献
90.
Orto PJ Nichol GS Okumura N Evans DH Arratia-Pérez R Ramirez-Tagle R Wang R Zheng Z 《Dalton transactions (Cambridge, England : 2003)》2008,(32):4247-4253
The reactions of the previously reported cluster complexes [Re(6)(mu(3)-Se)(8)(PEt(3))(5)I]I, trans-[Re(6)(mu(3)-Se)(8)(PEt(3))(4)I(2)], and cis-[Re(6)(mu(3)-Se)(8)(PEt(3))(4)I(2)] with the [Re(6)(mu(3)-Se)(8)](2+) core with CO in the presence of AgSbF(6) afforded the corresponding cluster carbonyls [Re(6)(mu(3)-Se)(8)(PEt(3))(5)(CO)][SbF(6)](2) (), trans-[Re(6)(mu(3)-Se)(8)(PEt(3))(4)(CO)(2)][SbF(6)](2) (), and cis-[Re(6)(mu(3)-Se)(8)(PEt(3))(4)(CO)(2)][SbF(6)](2) (). Infrared spectroscopy indicated weakening of the bond in CO, suggesting the existence of backbonding between the cluster core and the CO ligand(s). Electrochemical studies focusing on the reversible, one-electron oxidation of the cluster core revealed a large increase in the oxidation potential upon going from the acetonitrile derivatives to their carbonyl analogs, consistent with the depleted electron density of the cluster core upon CO ligation. Disparities between the IR spectra and oxidation potential between and indicate that electronic differences exist between sites trans and cis to the location of a ligand of interest. The active role played by the Se atoms in influencing the cluster-to-CO bonding interactions is suggested through this result and density functional (DF) computational analysis. The computations indicate that molecular orbitals near the HOMO account for backbonding interactions with a high percentage of participation of Se orbitals. 相似文献