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941.
Far infrared reflection and Raman spectra of InSe were measured at 5, 77 and 300 K. Phonon frequencies obtained by reflection spectra were well explained by two-point phonon combination. The crystal structure of-type was confirmed at low temperature. Ion blocking analysis supported also no change of phase by temperature in this semiconductor. 相似文献
942.
The soluble fraction of a cell extract of Saccharomyces cerevisiae was found to contain hydrolytic activity toward arginyl-arginyl-beta-naphthylamide (Arg-Arg-beta NA). Most of the contaminating Arg-beta NA hydrolysis activity was removed by diethylaminoethyl (DEAE)-cellulose column chromatography and the enzyme was partially purified. It is very similar in various properties to mammalian dipeptidyl aminopeptidase III (DAP III), although it differs slightly in some respects. 相似文献
943.
The Chao modification of the Redlich-Kister equation for correlating liquid activity coefficients is further modified to facilitate the evaluation of the constants. The determination of liquid activity coefficients at infinite dilutions by means of an ebulliometer with the consideration of vapor hold-up in the condenser is proposed. Both of these proposals are equally applicable to isothermal data and to isobaric data.For the purpose of illustration, vapor-liquid equilibrium data for the binary system acetone-methanol together with the azeotropic point and the liquid activity coefficients at infinite dilutions were determined at 760 Torr. The validity of the correlated data was confirmed with the enthalpies of mixing data at saturation, available in the literature. 相似文献
944.
Y. Awaya M. Akiba T. Katou Hidekazu Kumagai Y. Tendow K. Izumo T. Takahashi A. Hashizume M. Okano T. Hamada 《Physics letters. A》1977,61(2):111-113
The K X-rays from the target elements due to N-ion bombardment are measured with a crystal spectrometer. Some aspects owing to high incident energy are discussed. The Kα satellite, Kα hypersatellite and Kβ satellite peak spacings are obtained. 相似文献
945.
New types of some carbonyl- and cyano-phosphonium ylide complexes of palladium(II) were readily prepared in good yield by treatment of the corresponding bis(phosphonium)hexachlorodipalladate, [R3P+-CH2-Z]2[Pd2Cl6]2? (R3P = Ph3P, Z = COMe, COOEt, CONH2 or CN; R3P = PhMe2P, Z = COPh), with sodium acetate. 相似文献
946.
947.
948.
Sato M Furuike T Sadamoto R Fujitani N Nakahara T Niikura K Monde K Kondo H Nishimura S 《Journal of the American Chemical Society》2004,126(43):14013-14022
Mono-, di-, and trisialyloligosaccharides were introduced to mutant insulins through enzymatic reactions. Sugar chains were sialylated by alpha2,6-sialyltransferase (alpha2,6-SiaT) via an accessible glutamine residue at the N-terminus of the B-chain attached by transglutaminase (TGase). Sia2,6-di-LacNAc-Ins(B-F1Q) and Sia2,6-tri-LacNAc-Ins(B-F1Q), displaying two and three sialyl-N-acetyllactosamines, respectively, were administered to hyperglycemic mice. Both branched glycoinsulins showed prolonged glucose-lowering effects compared to native or lactose-carrying insulins, showing that sialic acid is important in obtaining a prolonged effect. Sia2,6-tri-LacNAc-Ins(B-F1Q), in particular, induced a significant delay in the recovery of glucose levels. 相似文献
949.
Abe T Sato C Ushirogochi H Sato K Takasaki T Isoda T Mihira A Yamamura I Hayashi K Kumagai T Tamai S Shiro M Venkatesan AM Mansour TS 《The Journal of organic chemistry》2004,69(18):5850-5860
A novel and mild method was established to synthesize 6-methylidene penem compounds. This method entails a MgBr(2)/Et(3)N-promoted aldol-type condensation on 6-bromopenem 12 with an appropriately substituted aldehyde to yield the intermediate acetylated bromohydrin, which was smoothly converted to the final product with simultaneous deprotection of C3 carboxylic acid ester using activated zinc dust and phosphate buffer at pH 6.5. This process provides a useful variation of C-C bond formation method for penem derivatives and also serves as a practical synthetic method to prepare 6-exomethylenepenem derivatives without racemization at the C5 position. 相似文献
950.
The first synthesis of mispyric acid (1), an inhibitor of DNA polymerase beta with a novel triterpene skeleton, was achieved by starting from isoprene (2), geraniol (6) and 1,5-dimethoxy-1,4-cyclohexadiene (14). The absolute configuration of the naturally occurring 1 was determined as 2S,4S. 相似文献