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101.
The C-S stretching vibrations of 28 aliphatic sulfides including one thiol are summarized, and all of the C-S stretching bands are classified into several groups. An extraordinarily low frequency associated with the ethyl group is discussed briefly. 相似文献
102.
103.
The crystallographic and magnetic properties of the compounds InM2+CrS4(M = Mn, Fe, Co, Ni) were studied. Three of these compounds except MnInCrS4 were antiferromagnetic. The Néel termperature and paramagnetic Curie temperature were determined to be 20 and 82K for InFeCrS4, 36 and 115K for InCoCrS4 and 22 and 26K for InNiCrS4, respectively. 相似文献
104.
105.
Aiura Y Yoshida Y Hase I Ikeda SI Higashiguchi M Cui XY Shimada K Namatame H Taniguchi M Bando H 《Physical review letters》2004,93(11):117005
We present detailed energy dispersions near the Fermi level along the high symmetry line GammaX on the monolayer and bilayer strontium ruthenates Sr2RuO4 and Sr3Ru2O7, determined by high-resolution angle-resolved photoemission spectroscopy. A kink in the dispersion is clearly shown for the both ruthenates. The energy position of the kink and the slope in the low-energy part near the Fermi level are almost identical between them, whereas the dispersion in the high-energy part varies, like the behavior of the kink for the cuprate superconductors. 相似文献
106.
107.
A new coordination mode of hydrotris(2-mercaptoimidazolyl)borate ligands was found in the reaction of [Na(Tm(tBu))] with Me(2)BiCl to form a trinuclear organobismuth complex [(Me(2)Bi)(3)(Tm(tBu))(2)](+)[Me(2)BiCl(2)](-)(Tm(tBu)= hydrotris(2-mercapto-1-tert-butylimidazolyl)borate). 相似文献
108.
109.
Development of a novel analytical method for determination of chondroitin sulfate using an in-capillary enzyme reaction 总被引:3,自引:0,他引:3
A novel analytical method for determination of total amount of chondroitin sulfate (CS) based on its conversion to desulfated chondro-disaccharide via an enzyme-catalyzed reaction, was developed. Using the in-capillary enzyme reaction, the method was also applied to the successful construction of an on-line analytical system. Within this system, electrophoretic migration was used to mix zones containing the enzyme mixture (chondroitinase ABC, chondro-4-sulfatase, chondro-6-sulfatase and 2-o-sulfatase) and the substrate (CS). The reaction was then allowed to proceed in the presence of a weak electric field and, finally, the product (desulfated chondro-disaccharide) of enzyme reaction migrated to the detector under the influence of an applied electric field. A polyvinyl alcohol-coated capillary was used to reduce protein adsorption. Desulfated chondro-disaccharide was successfully migrated toward the anode in 10 mM Tris-acetate buffer (pH 7.0) under reversed polarity and detected at 232 nm. The established method was validated and demonstrated to be applicable in the determination of total amount of CS in a commercial ophthalmic solution. No interference from the formulation excipients was observed. Good linearity was obtained, with correlation coefficients above 0.999. Recoveries and precisions ranged from 100.0 to 100.5%, and from 0.2 to 0.6% of the relative standard deviation, respectively. Good agreement was obtained between the established method and traditional photometric method based on carbazole reaction. In this study, application of the method to disaccharide compositional analysis was also performed. 相似文献
110.
Haraguchi K Shiina N Yoshimura Y Shimada H Hashimoto K Tanaka H 《Organic letters》2004,6(16):2645-2648
2'-Beta-methyl- and 2'-beta-hydroxymethyl-2'-deoxy-4'-thionucleosides have been synthesized through PhSeCl-mediated electrophilic glycosidation using 4-thiofuranoid glycals having carbon substituents at the C2-position as a glycosyl donor. Preparation of these glycals were carried out by means of the C2 lithiation of 1-chloro-4-thiofuranoid glycal with LTMP followed by the Birch reduction of the chlorine atom. [reaction: see text] 相似文献