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101.
Koichi KikuchiHiroyuki Nishikawa Isao IkemotoTakashi Toita Hiroki AkutsuShin'ichi Nakatsuji Jun-ichi Yamada 《Journal of solid state chemistry》2002,168(2):503-508
Three FeCl4 salts based on non-tetrathiafulvalene (TTF) donors, 2,5-bis(1,3-dithiolan-2-ylidene)-1,3,4,6-tetrathiapentalene (BDH-TTP) and 2,5-bis(1,3-dithian-2-ylidene)-1,3,4,6-tetrathiapentalene (BDA-TTP), have been prepared and characterized as κ-(BDH-TTP)2FeCl4, β-(BDA-TTP)2FeCl4, and (BDA-TTP)3FeCl4 · PhCl. The κ-(BDH-TTP)2FeCl4 salt, with a room-temperature conductivity (σrt) of 39 S cm−1, is metallic down to 1.5 K, and its magnetic susceptibility obeys the Curie-Weiss law with a Curie constant (C) of 4.25 emu K mol−1 and a Weiss constant (θ) of 0.041 K. β-(BDA-TTP)2FeCl4 exhibits metallic behavior (σrt=9.4 S cm−1) with a sharp metal-to-insulator (MI) transition (TMI=113 K) and antiferromagnetic ordering with the Néel temperature of near 8.5 K, whereas the solvated (BDA-TTP)3FeCl4 · PhCl salt is a semiconductor with a thermal activation energy of 0.11 eV (σrt=2.0× 10−2 S cm−1) and exhibits Curie-Weiss behavior (C=4.42 emu K mol−1, θ=−0.35 K). 相似文献
102.
103.
Kazuhisa Hiratani Isao Nozawa Tsutomu Nakagawa Sumio Yamada 《Journal of membrane science》1982,12(2):207-215
The effects of acid and cation concentration on the uphill transport rates of cations and selectivities through chloroform liquid membrane by noncyclic polyether ionophores, which are pentaethylene glycol derivatives containing both 8-quinolyt and o-carboxylphenyl terminal groups, have been demonstrated. Using sulfuric, oxalic, or polyphosphoric acid in aqueous solution, the initial transport rates and the amount of cation transported by the ionophores after two days were larger than those using hydrochloric or nitric acid. Using picric acid, the amount of cation transported decreased greatly. It was confirmed that it decreased where an acid could easily be counter-transported by the ionophore through liquid membranes. On the other hand, it was found that the rates, amounts of cation transported, and selectivities, change with the changing of the cation concentration in the aqueous solutions. When the cation concentration in both aqueous solutions is high enough compared with the pH gradient between the two aqueous solutions, the rate, amount, and selectivity of the ionophore for potassium ion increases compared with when the cation concentration is low. 相似文献
104.
Minoru Kumakura Masaru Yoshida Isao Kaetsu 《Applied biochemistry and biotechnology》1978,3(3):175-183
The immobilization ofStreptomyces phaeochromogenes cells was studied by the radiation-induced polymerization of various hydrophobic glass-forming monomers at low temperatures. The glucose isomerase activity of cells immobilized in hydrophobic polymers showed no decrease in activity with repeated use (batch enzyme reaction). Activity increased with increasing monomer concentration in contrast to results with the immobilized enzyme. The hydrophobic polymer composite was microspheric in form. The particle diameter of the composite increased with the increasing monomer concentration.K m values of the immobilized cells were close to that of intact cells. It was deduced that the cells were trapped on the surface part of the hydrophobic polymer ready to react with the substrate, and not within the matrix where diffusion would play an important role in reaction rates. 相似文献
105.
Various kinds of alcohols bearing phenylthio or phenylseleno moiety were converted into the corresponding carbonyl compounds in good to excellent yields by treating with dimesityl diselenide and -butyl hydroperoxide. 相似文献
106.
Under the effect of butyllithium, 1-trimethylsilylpropargyl alcohol undergoes rearrangement to afford the corresponding trimethylsiloxyallene or its lithiated one, which can be used for the preparation of α,β-unsaturated ketone derivatives. 相似文献
107.
A new synthetic approach to quinazolines bearing a carboxy group is described. Reaction of 5-carbonyl substituted 1,3,6-tri-methyluracils (I) with dimethyl acetylenedicarboxylate or electron-deficient olefines affords quinazoline derivatives (III-VI) pyrimidine(Z)-dienols (II) formed by base-catalyzed isomerization. 相似文献
108.
Dye-sensitized photooxygenation of enol ethers of methyl phenylpyruvates () produced diendoperoxides in aprotic solvents, whereas in methanol hydroxylated product was obtained. The reaction scheme is discussed in comparison uith that for the enzymic transformation. 相似文献
109.
Tamotsu Kamiya Kuniyuki Goto Isao Shinohara 《Journal of polymer science. Part A, Polymer chemistry》1979,17(2):561-569
The ionene polymers were prepared by the Menshutkin reaction of α,ω-dibromoalkane (n) with triethylenediamine (TDA) or 4,4′-bipyridil (BP). Resistivities (p) and activation energies of conduction (Ea) were measured for the polymeric 7,7,8,8-tetracyanoquinodimethan (TCNQ) salts with these ionenes. The correlation between the chemical structure of the ionenes and the conductivity was discussed. In the TDA,n-TCNQ complex salts and the BP,n-TCNQ simple salts the salts of the ionenes containing even numbers of CH2 groups showed higher conductivities than those of the ionenes containing odd numbers of CH2 groups. The conductivities determined by the narrower interval between the N+ cations of the main chains were measured in the simple salts. In the complex salts the conductivities determined by the larger interval were measured. The conformational change of the matrix ionenes affected the arrangement of the TCNQ molecules. The values of p were 79.7 and 12.5 Ω cm, and the values of Ea were 0.122 and 0.063 eV for TDA,4-TCNQ complex salt and BP,5-TCNQ complex salt, respectively. 相似文献
110.
Yoshiaki Nakamoto Isao Karube Seikichi Terawaki Shuichi Suzuki 《Applied biochemistry and biotechnology》1976,1(2):143-149
Collagen fibrils were modified with β-l-[3,3-dimethyl-6′-nitrospiro-(indoline-2,2′-2H-benzopyran)] propionic anhydride. The spiropyran collagen membrane showed reverse photochromism. Lactate dehydrogenase (LDH, E.C. 1.1.1.27) was entrapped in the spiropyran collagen membrane. The activity of the LDH-spiropyran collagen membrane decreased under visible-light irradiation, and then increased again after incubation in the dark. The optimum pH of the LDH-spiropyran collagen membrane was displaced toward lower pH values under visible-light irradiation. The activity change of the LDH-spiropyran collagen membrane under visible-light irradiation depended on the LDH content. 相似文献