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171.
172.
A new supramolecular chirogenic system on the basis of tetrakis(nickel porphyrin) and various enantiopure solvents, which was specifically designed for investigation of the chirogenic phenomenon upon extremely weak interaction modes and marginal chiroptical responses, is reported. The temperature was found to be a key factor controlling the chirality transfer process in these assemblies. 相似文献
173.
Journal of Algebraic Combinatorics - We study the change of the minimal degree of a logarithmic derivation of a hyperplane arrangement under the addition or the deletion of a hyperplane and give a... 相似文献
174.
Squalene-hopene cyclase (SHC) converts squalene (C(30)) into pentacyclic triterpenes of hopene and hopanol. A linear sesquiterpene, (6E,10E)-2,6,10-trimethyldodeca-2,6,10-triene, underwent cyclization catalyzed by SHC, affording the following six bicyclic sesquiterpenes (drimane skeleton) in relatively high yield (68%): drim-7(8)-ene, drim-8(12)-ene, drim-8(9)-ene, driman-8α-ol, driman-8β-ol, and the novel sesquiterpene, named quasiclerodane, the skeleton of which is analogous to that of clerodane diterpene. To extend the scope of the enzymatic syntheses, acyclic sesquiterpenes to which a phenol moiety was appended were subjected to the enzymatic reaction catalyzed by SHC. The cyclic meroterpene core present in hongoquercins A and B was successfully prepared. The formation mechanisms of drimane-type sesquiterpenes and the cyclic meroterpene core of hongoquercins A and B are discussed. 相似文献
175.
Takahashi H Niidome Y Niidome T Kaneko K Kawasaki H Yamada S 《Langmuir : the ACS journal of surfaces and colloids》2006,22(1):2-5
Hexadecyltrimethylammonium bromide (CTAB), which is necessary for the preparation of gold nanorods (NRs), was extracted from a NR solution into a chloroform phase containing phosphatidylcholine (PC). After three extractions, the zeta potential of the NRs remained positive, but its magnitude decreased from +67 +/- 1 to +15 +/- 1 mV. Transmission electron microscopy and energy-dispersive X-ray analysis indicated that the NRs were passivated with PC. The PC layer on the NR surface contributed to the prevention of NR aggregation. The PC-passivated NRs showed low cytotoxicity in comparison with twice-centrifuged NRs. It was shown that a negligible amount of CTAB was dispersed in the NR solution after the extraction. The extraction using a chloroform phase containing PC was found to be a convenient way of replacing the CTAB with alternative capping agents such as PC. This is a key technique for preparing functional NRs that can have practical applications. 相似文献
176.
Biniwale RB Kariya N Yamashiro H Ichikawa M 《The journal of physical chemistry. B》2006,110(7):3189-3196
Dehydrogenation of cyclohexane over Pt/alumite and Pt/activated carbon catalysts has been carried out for hydrogen storage and supply to fuel cell applications. An unsteady state has been created using spray pulsed injection of cyclohexane over the catalyst surface to facilitate the endothermic reaction to occur efficiently. Higher temperature of the catalyst surface is more favorable for the reaction, thus the heat transfer phenomena and temperature profile under alternate wet and dry conditions created using spray pulsed injection becomes important. IR thermography has been used for monitoring of temperature profile of the catalyst surface simultaneously with product analysis. The heat flux from the plate-type heater to the catalyst has been estimated using a rapid temperature recording and thermocouple arrangement. The estimated heat flux under transient conditions was in the range of 10-15 kW/m(2), which equates the requirement for endothermic reactions to the injection frequency of 0.5 Hz, as used in this study. The analysis of temperature profiles, reaction products over two different supports namely activated carbon cloth and alumite, reveals that the more conductive support such as alumite is more suitable for dehydrogenation of cyclohexane. 相似文献
177.
Han A Sonoda T Kang JH Murata M NIiidome T Katayam Y 《Combinatorial chemistry & high throughput screening》2006,9(1):21-25
Proteases play a key role in cell functions, and it is very important to monitor their activities for drug screening and diagnosis of diseases. In the present study, a new class of fluorescence probe, into which a fluorophore and a quencher have been introduced, was developed and applied to the on-chip detection of caspase-3 activity. This probe is non fluorescent in the absence of caspase-3. However, when it is treated with active caspase-3, the fluorescence intensity increases dependent on the caspase-3 activity due to the cleavage of the quencher-containing moiety on a glass slide. This caspase-dependent increase in the fluorescence intensity was also detected when the glass slide immobilizing the probe peptide was treated with cell lysate stimulated by staurosporine (STP), which is an apoptosis-inducing agent. On the other hand, such an increase was not detected in the case of control cell lysate without STP-stimulation. The developed system is a rapid and sensitive method and is useful for the direct measurement of protease activity on a glass array. 相似文献
178.
Masahiro Sadakane Prof. Dr. Keiko Yamagata Katsunori Kodato Keisuke Endo Koshiro Toriumi Prof. Dr. Yoshiki Ozawa Prof. Dr. Tomoji Ozeki Prof. Dr. Takuro Nagai Dr. Yoshio Matsui Dr. Norihito Sakaguchi Prof. Dr. William D. Pyrz Douglas J. Buttrey Prof. Douglas A. Blom Dr. Thomas Vogt Dr. Wataru Ueda Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(21):3782-3786
Mix and match : The pentagonal [Mo6O21]n? polyoxomolybdate building block assembles with other sources of Mo, V, and Sb ions to form an orthorhombic Mo‐V‐Sb oxide. The first single‐crystal X‐ray analysis of an orthorhombic Mo–V‐based oxide, a promising catalyst for light alkane selective oxidation known as the “M1 phase”, revealed the structure of the compound.