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781.
Michio Yamanaka Yuichi Takajo Shinji Ono Hitoshi Matsuki Shoji Kaneshina 《Colloid and polymer science》2007,285(7):761-769
Densities of aqueous solutions of lithium 1-naphthylsulfonate (1-LiNSO)–lithium decylsulfonate (LiDeSO) and 2-LiNSO–LiDeSO
mixtures were measured as a function of total molality and composition of the mixtures. The partial derivative of the solution
with respect to the total molality was calculated for the monomer and micellar regions. It was found that the values of the
partial derivative are larger for the 2-LiNSO–LiDeSO system than for the 1-LiNSO–LiDeSO system. This fact is attributable
to the larger value of the partial molar volume of monomer of 2-LiNSO than that of 1-LiNSO. For the two systems, the micellar
molar volume of the mixtures varied linearly with the composition from the partial molar volumes of 1- and 2-LiNSO in their
single systems to the micellar molar volume in the single LiDeSO system. Miscibility of the solutes in the mixed micelles
was examined by drawing the critical micelle concentration (CMC) vs composition diagrams. The diagrams for the 1- and 2-isomers
coincided with each other and showed that molecules of 1- and 2-LiNSO are excluded from the micelles. The contribution of
the micelle-unforming component to the volume of micelle formation is positive and large because of the exclusion from the
micelles. On the other hand, the contribution of the micelle-forming component to the volume of micelle formation is unchanged.
The dependence of the monomer molalities of LiNSO and LiDeSO on the total molality, evaluated by means of the CMC vs composition
diagrams, substantiated the validity of the approximations used in the derivation of the equations in this study. 相似文献
782.
Mukaiyama H Nishimura T Shiohara H Kobayashi S Komatsu Y Kikuchi S Tsuji E Kamada N Ohnota H Kusama H 《Chemical & pharmaceutical bulletin》2007,55(6):881-889
We synthesized a series of novel 2-anilinopyrazolo[1,5-a]pyrimidine derivatives and evaluated their ability to inhibit c-Src kinase; 7-(2-amino-2-methylpropylamino)-5-cyclopropyl-2-(3,5-dimethoxyphenylamino)pyrazolo[1,5-a]pyrimidine-3-carboxamide 7o and 7-(2-amino-2-methylpropylamino)-2-(3,5-dimethoxyphenylamino)-5-methylpyrazolo[1,5-a]pyrimidine-3-carboxamide 7f showed potent inhibitory activity. Compound 7f inhibited c-Src selectively and exhibited satisfactory central nervous system (CNS) penetration. Furthermore, 7f.HCl reduced the infarct volume in vivo in a rat middle cerebral artery (MCA) occlusion model when administrated intraperitoneally. 相似文献
783.
Maeda Y Yamauchi H Fujisawa M Sugihara S Ikeda I Aoshima S 《Langmuir : the ACS journal of surfaces and colloids》2007,23(12):6561-6566
Hydration changes of poly(2-methoxyethyl vinyl ether) (PMOVE) synthesized via living cationic polymerization have been investigated during a temperature-responsive phase separation in water by using infrared spectroscopy. An aqueous PMOVE solution has lower critical solution temperatures (LCSTs) of 66 degrees C in H2O and 65 degrees C in D2O at approximately 15 wt %. During phase separation, the C-H stretching (nu(C-H)) bands of PMOVE shift downward (red shift). In particular, the IR band assigned to the antisymmetric stretching vibration of the terminal methyl groups exhibits a remarkably large red shift by 16 cm-1. The band also exhibits a red shift with increasing polymer concentration at T < Tp. Density functional theory (DFT) calculations of the models of hydrated PMOVE indicate that the shift is due mainly to the breaking of hydrogen bonds (H-bonds) between the oxygen of the methoxy groups and water and partially to the breaking of the CH...O H-bond to them. 相似文献
784.
Dye-sensitized TiO2 solar cells using imidazolium-type ionic liquid crystal systems as effective electrolytes 总被引:1,自引:0,他引:1
Yamanaka N Kawano R Kubo W Masaki N Kitamura T Wada Y Watanabe M Yanagida S 《The journal of physical chemistry. B》2007,111(18):4763-4769
A novel ionic liquid crystal (ILC) system (C(12)MImI/I(2)) with a smectic A phase used as an electrolyte for a dye-sensitized solar cell (DSSC) showed the higher short-circuit current density (J(SC)) and the higher light-to-electricity conversion efficiency than the system using the non-liquid crystalline ionic liquid (C(11)MImI/I(2)), due to the higher conductivity of ILC. To investigate charge transport properties of the electrolytes in detail, the exchange reaction-based diffusion coefficients (D(ex)) were evaluated. The larger D(ex) value of ILC supported that the higher conductivity of ILC is attributed to the enhancement of the exchange reaction between iodide species. As a result of formation of the two-dimensional electron conductive pathways organized by the localized I(3)- and I- at S(A) layers, the concentration of polyiodide species exemplified by I(m)- (m = 5, 7, ...) was higher in C(12)MImI/I(2). However, as the increment of the concentration of polyiodide species is less than that of D(ex), the contribution of a two-dimensional structure of the conductive pathway through the increase of collision frequency between iodide species was proposed. Furthermore, a quasi-solid-state ionic liquid crystal DSSC was successfully fabricated by employing a low molecular gelator. Addition of the 5.0 g/L gelator to ILC improved light-to-electricity conversion efficiency through the increase of J(SC) due to the enhancement of the conductivity in C(12)MImI/I(2)-gel. 相似文献
785.
采用自动前处理LC/MS进行血浆中药物的快速分析 总被引:3,自引:0,他引:3
药物研究的发展对高通量的样品处理分析提出了越来越高的要求,减少样品制备时间和分析时间是解决问题的关键。我们新近发展了一种具有在线稀释旁路和新的样品预处理柱的Shim-Pack MAYI-ODS自动柱切换HPLC和LC/MS系统,该系统无需样品前处理,可直接进样进行血浆、血清中的药物分析。本文利用自动样品前处理LC/MS系统,用ODS整体柱实现了血浆中药物的快速分析。包括样品预处理,整个分析仅需1.2min完成。 相似文献
786.
Toshiaki Kabe Atsushi Ishihara Weihua Qian Azumi Funato Takenobu Kawano 《Reaction Kinetics and Catalysis Letters》1999,68(1):69-75
In hydrodesulfurization of radioactive35S-labeled dibenzothiophene catalyzed by CrO3/Al2O3, it was found that sulfur on sulfided CrO3/Al2O3 was more labile than those on MoO3/Al2O3 and WO3/Al2O3, while the amount of sulfur was less than that on MoO3/Al2O3.
Dedicated to Professor Pál Tétényi on the occasion of his 70th birthday 相似文献
787.
Qihua Yang Mahendra P. Kapoor Shinji Inagaki Nao Shirokura Junko N. Kondo Kazunari Domen 《Journal of molecular catalysis. A, Chemical》2005,230(1-2):85-89
The first catalytic applications of sulfonic acid-functionalized hydrophobic mesoporous benzene–silica with lamellar pore wall structure are reported. The mesoporous benzene–silica attached with propylsulfonic groups to the crystal-like periodic pore walls exhibited the catalytic activity in the esterification of acetic acid with ethanol. The catalytic results show the higher conversion compared to the commercial Nafion-H. 相似文献
788.
789.
Dr. Shin‐ichiro Kawano Takashi Hamazaki Atsushi Suzuki Kenshin Kurahashi Prof. Dr. Kentaro Tanaka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(44):15674-15683
A new series of shape‐persistent imine‐bridged macrocycles were synthesized based on dynamic covalent chemistry. The macrocycles had an alternating sequence of dibenzothiophene and N,N′‐bis(salicylidene)‐ethylenediamine (salen) tethering branched alkyl chains. The macrocycles and tetranuclear metallomacrocycles bearing long and branched alkyl chains exhibited thermotropic columnar liquid‐crystalline phases over a wide temperature range and the metallomacrocycles greatly depended on the characteristics of the coordinated metal ions. The metal‐free macrocycle showed a liquid‐crystalline phase with a lamellar structure and poor birefringence. In sharp contrast, the macrocyclic Ni complex showed a columnar oblique liquid‐crystalline phase, whereas the Pd and Cu complexes showed columnar liquid‐crystalline phases with a lamellar structure. The macroscopic organization and thermal properties of the corresponding liquid‐crystalline metallomacrocycles were significantly dependent on the subtle structural differences among the planar macrocycles, which were revealed by single‐crystal X‐ray crystallographic analysis of the macrocycles with shorter alkyl chains. 相似文献
790.
Inside Cover: Collective Synthesis and Biological Evaluation of Tryptophan‐Based Dimeric Diketopiperazine Alkaloids (Chem. Eur. J. 4/2016) 下载免费PDF全文