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141.
Tsuneyuki Sato Osamu Ito Shigeki Mori Takayuki Otsu 《Journal of polymer science. Part A, Polymer chemistry》1984,22(7):1661-1676
Poly(dimethylaminoethyl methacrylate N-oxide) (poly(DMAEMNO)) was prepared by oxidation of poly(dimethylaminoethyl methacrylate) with hydrogen peroxide in methanol. From thermogravimetric and IR spectroscopic investigations Cope elimination of amine oxide group in poly(DMAENO) was found to occur at 120–150°C. The postpolymerization of partially pyrolyzed polymer carrying vinyl ester group as pendant was performed with azobisisobutyronitrile at 60°C in methanol to give cross-linked polymer that was found to form hydrogel. Poly(DMAEMNO) gave metal–polymer complexes with CuCl2, ZnCl2, and CoCl2. Cobalt–polymer complex had a constitution of 1:2 of metal ion to amine oxide group, while copper– and zinc–polymer complexes seemed to have structures of 1:1 and 1:2 of metal ion to amine oxide group. Furthermore, polymer complexes of poly(DMAEMNO) with poly(methacrylic acid) and poly(acrylic acid) were found to be formed by mixing aqueous solutions of both polymers and also by radical polymerization of the acid monomers in the presence of poly(DMAEMNO). From elemental analysis, thermogravimetric investigation, and measurement of turbidity it was concluded that the resulting polymer–polymer complexes contained more than one acid monomer unit per one N-oxide unit. 相似文献
142.
H. Mori H. Suzuki T. Okano H. MoriyamaY. Nishio K. KajitaM. Kodani K. TakimiyaT. Otsubo 《Journal of solid state chemistry》2002,168(2):626-631
The symmetric (s-) and unsymmetric (us-) BEDT-STF (=bis(ethylenedithio)diselenadithia-fulvalene) salts were prepared, and their crystal structures and electrical resistivities were investigated. Four us-BEDT-STF salts have the positional disorder of the Se atoms in the STF framework in crystals, whereas three s-BEDT-STF salts have no disorder. When κ-(us-BEDT-STF)2GaCl4 and κ-(cis-s-BEDT-STF)2GaCl4 are compared, the latter without the positional disorder of the Se atoms is more conductive than the former one with the disorder. 相似文献
143.
N Kubodera K Miyamoto M Akiyama M Matsumoto T Mori 《Chemical & pharmaceutical bulletin》1991,39(12):3221-3224
Three vitamin D3 analogues, 1 alpha,25-dihydroxy-23-oxavitamin D3 (3), 1 alpha,25-dihydroxy-23-thiavitamin D3 (4) and 1 alpha,25-dihydroxy-23-azavitamin D3 (5) were synthesized. In the differentiation-inducing activity of human myeloid leukemia cells into macrophages in vitro, the 23-aza analogue (5) showed the least activity, while no remarkable differences were observed between the 23-oxa analogue (3) and the 23-thia analogue (4), which were less active than 1 alpha,25-dihydroxyvitamin D3 (1). 相似文献
144.
Xu Q Tanaka K Mori M Helaleh MI Hu W Hasebe K Toada H 《Journal of chromatography. A》2003,997(1-2):183-190
A monolithic ODS-silica gel column modified by saturating it with lithium dodecylsulfate (Li-DS) was used to demonstrate the high-speed separation of H+ from other mono- and divalent cations, such as Na+, NH4+, K+, Mg2+ and Ca2+ using ion chromatography (IC). Using a 5 mM EDTA-2K solution containing 0.10 mM Li-DS (pH 4.80) as eluent, H+ was eluted with a sharp and symmetrical peak within 1.0 min before other cations at a flow-rate of 1.5 ml min(-1). The rapid elution of H+ and its conductimetric detection could be attributed to the presence of EDTA (HY2-), which can convert H+ ions as anions. i.e. H(+) + H2Y(2-) --> H3Y(-). The acidity of rainwater and deionized water samples was determined using this IC system with satisfactory results. 相似文献
145.
Reduction followed by cyclization of (Z)-methyl 3-(6-azido-3-chloro-1-methyl-4-oxo-1,4-dihydropyridazin-5-yl)-2-methylacrylate (I) to pyrido[2,3-c]pyridazines by treatment with triethyl phosphite or hydrazine hydrate as the reducing agents is described. Compound I was also reductively cyclized with sodium borohydride. Treatment of I with concentrated sulfuric acid gave 8-chloro-3,6-dimethyl-2,5-dioxo-5,6-dihydro-2H-pyrano[2,3-d] pyridazine (VII) which also could be synthesized by another independent route. A mechanism for the cyclization is proposed. 相似文献
146.
Hu W Haddad PR Tanaka K Sato S Mori M Xu Q Ikedo M Tanaka S 《Journal of chromatography. A》2004,1039(1-2):59-62
A new ion chromatographic (IC) system has been established by using micelles of 3-(N,N-dimethylmyristylammonio)propanesulfonate (Zwittergent 3-14) loaded onto a reversed-phase packed column as the separation column with an electronic rotary switching valve packed-bed suppressor for conductometric detection of inorganic anions. An aqueous H3BO3-Na2B4O7 solution has been demonstrated to be the most desirable eluent for this IC system. The relationship between retention time and the concentration of the borate eluent was determined for a series of model anionic analytes and this relationship was found to be opposite to that exhibited in a conventional anion-exchange IC system. The rapid elution and complete separation of monovalent inorganic anions were obtained by initially using a high-concentration borate solution as the eluent for a short-period, and then switching to a lower-concentration borate eluent to complete the separation. Detection limits for nitrite, bromide, nitrate, and chlorate were 0.85, 0.88, 0.95 and 4.8 microM, respectively, when a 7.0 mM Na2B4O7 eluent was used. Moreover, the ability to directly detect these monovalent anions in samples containing high concentrations of sulfate and/or chloride ions provided a major advantage of this approach. 相似文献
147.
Y Yoshikuni Y Ezure T Seto K Mori M Watanabe H Enomoto 《Chemical & pharmaceutical bulletin》1989,37(1):106-109
Various N-substituted derivatives of 4-O-alpha-D-glucopyranosylmoranoline have been synthesized, and their inhibitory activities against rabbit sucrase and maltase have been measured, as well as their effects on postprandial hyperglycemia in the sucrose-loaded rat, 4-O-alpha-D-Glucopyranosylmoranoline was also shown to have potent hypoglycemic activity in starch-loaded dogs. 相似文献
148.
An improved spectrophotometric determination of uranium(VI) is proposed using 4-(2-pyridylazo)resorcinol(PAR) in the presence of benzyldimethylstearyltrimethylammonium chloride(BSTAC) as a cationic surfactant. The calibration graph is linear in the range of 0.3-60 microg/10 ml uranium(VI), measuring the absorbance at 550 nm. The reproducibility for 19.0 microg/10 ml uranium(VI) is 0.57%. The third-derivative method using the third-derivative distance (d(3)A/dlambda(3)) among lambda(1) 530 nm, lambda(3) 594 nm and lambda(2) 565 nm was also investigated. 相似文献
149.
H Oka Y Ikai N Kawamura K Uno M Yamada K Harada M Uchiyama H Asukabe Y Mori M Suzuki 《Journal of chromatography. A》1987,389(2):417-426
A simple, rapid and precise analytical method for the residual tetracyclines in honey has been established using a tandem cartridge clean-up system (prepacked reversed-phase and ion-exchange cartridges) followed by high-performance liquid chromatography. The recoveries of oxytetracycline (OTC), tetracycline (TC), chlortetracycline (CTC) and doxycycline (DC) from honey spiked at a level of 1.0 ppm are 87.1, 85.3, 98.0 and 99.0%, respectively, with coefficients of variation of 1.1-3.9%. The detection limits in honey are 0.02 ppm for OTC and TC, and 0.05 ppm for CTC and DC, respectively. The time required for the analysis of four samples is only 1 h. 相似文献
150.
A new synthesis of (±), (+)- and (-)-lineatin (3,3,7-trimethyl-2, 9-dioxatricyclo [3.3.1.04,7] nonane, ) was achieved. The stereochemistry of (+)-lineatin was established as 1, 4, 5, 7 by an X-ray crystallographic analysis of an intermediate . 相似文献