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141.
S. Maruyama M. Y. Lee R. E. Haufler Y. Chai R. E. Smalley 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1991,18(4):409-412
The kinetics of cluster formation in supersonic jets is examined by numerical integration of the master equation system. Some general characteristics of cluster kinetics could be formulated. Excellent agreement between experimental curves of p-cresol (H2O)0, 1, 2, 3 formation as function of H2O pressure and the corresponding calculated curves were obtained assuming successive cluster formation. From the kinetic curves, an unambiguous assignment of cluster size was possible which agreed with mass-resolved REMPI measurements. The fit of the rate coefficients shows the formation of p-cresol (H2O)1 to be faster than p-cresol (H2O)2 and p-cresol (H2O)3. 相似文献
142.
143.
Cholesterol-based hydrogen-bonded liquid crystals 总被引:1,自引:0,他引:1
Hydrogen bonding is a powerful tool for assembling molecules and building new liquid crystalline structures. In this study, non-symmetric dimesogens were prepared by intermolecular hydrogen bonding between rationally designed H-bond donor (3-cholesteryloxycarbonylpentanoic acid) and acceptor (4-(pyridine-4-ylmethyleneimino)phenyl 4-alkoxybenzoate) moieties. Their liquid crystalline properties were investigated by differential scanning calorimetry, polarized optical microscopy and X-ray diffraction. Cholesteric and smectic phases were observed. As for the covalently linked dimesogens, several types of smectic periodicities occur for these H-bonded cholesteryl compounds depending on the molecular parameters. 相似文献
144.
145.
Kommareddi Nagesh S. Tata Murthy Karayigitoglu Cigdem John Vijay T. McPherson Gary L. Herman Michael F. O'Connor Charles J. Lee Young-Sook Akkara Joseph A. Kaplan David L. 《Applied biochemistry and biotechnology》1995,51(1):241-252
Applied Biochemistry and Biotechnology - Horseradish peroxidase has been used as a biocatalyst to synthesize a polymeric material from alkyl-substituted phenols. The synthesis is carried out in a... 相似文献
146.
Gupta Rajinder K. Deobald Lee A. Crawford Don L. 《Applied biochemistry and biotechnology》1990,24(1):899-911
Applied Biochemistry and Biotechnology - Coal metabolizingPseudomonas cepacia DLC-07 was isolated from soil and shown to use soluble lignite coal as a carbon/energy source.Pseudomonas modified coal... 相似文献
147.
148.
Jiann-Kuan Luo Kazufumi Takahashi J. Dew Mckenney Raymond N. Castle Milton L. Lee 《Journal of heterocyclic chemistry》1989,26(6):1845-1848
The synthesis of 2-naphthyl 2′-dibenzothienyl ether, 1-(1′-naphthyl)-2-(4″-acridinyl)ethane and a series of naphthylethyldibenzothiophenes is reported. 相似文献
149.
150.
ω-Tetrahydropyran-2-ylsulfanylalkylmagnesium chlorides are prepared as Grignard reagents containing protected mercaptoalkyl chains, which are useful for the direct introduction of ω-mercaptoalkyl chains to electrophiles. In order to prove the usefulness of these reagents, they were reacted with buckminsterfullerene (C60) to give 1-(ω-mercaptoalkyl)-1,2-dihydrobuck minsterfullerenes after the deprotection of THP group with TFA. 相似文献