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21.
Konieczny MT Konieczny W Okabe S Tsujimoto H Suda Y Wierzba K 《Chemical & pharmaceutical bulletin》2006,54(3):350-353
Biological activity of thioaurones was not tested so far and the group constitute completely unexplored source of new molecules of pharmacological interest. We report synthesis and evaluation of cytotoxic activity of thioaurone derivatives bearing p-hydroquinone system in ring A. Their activity was found to depend strongly on substitution pattern, so eventually both the activity and pharmacokinetic parameters of the molecules could be tailored by further structural modifications. 相似文献
22.
23.
Wang X Guo Y Shi Y Belik AA Tsujimoto Y Yi W Sun Y Shirako Y Arai M Akaogi M Matsushita Y Yamaura K 《Inorganic chemistry》2012,51(12):6868-6875
The postspinel mineral MgAl(2)O(4) exists only under the severe pressure conditions in the subducted oceanic lithosphere in the Earth's deep interior. Here we report that its analogous oxide CdRh(2)O(4) exhibits a structural transition to a quenchable postspinel phase under a high pressure of 6 GPa at 1400 °C, which is within the general pressure range of a conventional single-stage multianvil system. In addition, the complex magnetic contributions to the lattice and metal nonstoichiometry that often complicate investigations of other analogues of MgAl(2)O(4) are absent in CdRh(2)O(4). X-ray crystallography revealed that this postspinel phase has an orthorhombic CaFe(2)O(4) structure, thus making it a practical analogue for investigations into the geophysical role of postspinel MgAl(2)O(4). Replacement of Mg(2+) with Cd(2+) appears to be effective in lowering the pressure required for transition, as was suggested for CdGeO(3). In addition, Rh(3+) could also contribute to this reduction, as many analogous Rh oxides of aluminous and silicic minerals have been quenched from lower-pressure conditions. 相似文献
24.
ω-(Phenylthio)-ω-chloroalkyl acetates were allowed to react with MeLi (3.2 equiv) to give 2-(phenylthio) cycloalkanols which were produced by the regioselective intramolecular insertion by (phenylthio) carbenes. 相似文献
25.
S. Ishio M. Fujikura T. Ishii M. Takahashi 《Journal of magnetism and magnetic materials》1986,60(2-3):236-242
The magnetic and mechanical properties of amorphous Fe100−xYx alloys (20 ≤ x ≤ 60) fabricated by rapid quenching have been measured. The dependence of the density, Young's modulus and magnetic moment per Fe atom on x shows a break point between x = 30 and 40, accompanied by a drastic change in the X-ray diffraction pattern. The spontaneous volume magnetostriction as well as the forced volume magnetostriction are a maximum at x = 20 and decrease rapidly with increasing x. The variation of the magnetic and mechanical properties with x is explained by a change of the local atomic arrangement in the amorphous state, reflecting the structure of corresponding crystalline compounds. 相似文献
26.
A. Mizohata T. Mamuro T. Tsujimoto 《Journal of Radioanalytical and Nuclear Chemistry》1978,42(1):143-152
Instrumental neutron activation analysis was applied to multielement trace analysis of high purity aluminium samples. In order
to reduce the production of24Na from the matrix, samples were activated by thermal neutron flux of high cadmium ratio. Detection limits of various impurity
elements were evaluated. So called “five nine” class standard aluminium samples were analyzed and concentrations of various
impurity elements were determined. The analytical results obtained on zone refined aluminium samples showed that zone refining
is effective against many elements, such as Na, Cr, Fe, Co, Cu, Ga, As, Br, Ba, La, Ce, Sm, Yb, Lu, Hf, W, Th and U, but not
very effective against the element Sc. 相似文献
27.
Naoki Hayakawa Kazuya Sadamori Shota Tsujimoto Prof. Dr. Miho Hatanaka Prof. Dr. Tomonari Wakabayashi Prof. Dr. Tsukasa Matsuo 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(21):5859-5863
The reaction of the bulky diphosphenes (Rind)P=P(Rind) ( 1 ; Rind=1,1,3,3,5,5,7,7-octa-R-substituted s-hydrindacen-4-yl) with two molecules of N-heterocyclic carbene (NHC; 1,3,4,5-tetramethylimidazol-2-ylidene) resulted in the quantitative formation of the NHC-bound phosphinidenes NHC→P(Rind) ( 2 ), along with the cleavage of the P=P double bond. The reaction times are dependent on the steric size of the Rind groups (11 days for 2 a (R=Et) and 2 h for 2 b (R=Et, Me) at room temperature). The mechanism for the double bond-breaking is proposed to proceed via the formation of the NHC-coordinated, highly polarized diphospehenes 3 as an intermediate. Approach of a second NHC to 3 induces P−P bond cleavage and P−C bond formation, which proceeds through a transition state with a large negative Gibbs energy change to afford the two molecules of 2 , thus being the rate-determining step of the overall reaction with the activation barriers of 80.4 for 2 a and 29.1 kJ mol−1 for 2 b . 相似文献
28.
H. Hatakeyama Y. Tsujimoto M. Ja. Zarubin S. M. Krutov T. Hatakeyama 《Journal of Thermal Analysis and Calorimetry》2010,101(1):289-295
Thermal properties of industrial hydrolysis lignin (HL) obtained from bio-ethanol production plants were investigated by thermogravimetry
and differential scanning calorimetry. Thermal decomposition of HL was observed in two stages suggesting coexisting carbohydrates.
Glass transition temperature (T
g) was observed in a temperature range from 248 to 363 K. T
g values were lower than that of other industrial lignins, such as kraft lignin or lignosulfate. Enthalpy relaxation was observed
as sub-T
g, which is not as prominent as other industrial or laboratory scale isolated lignins. T
g of HL decreased in the presence of water and saturated at water content (W
c) of 0.18 (mass of water/mass of dry HL). The amount of bound water calculated from melting enthalpy of water and W
c was ca. 0.18. Thermal decomposition and molecular motion of as obtained industrial HL are affected by coexisting carbohydrates. 相似文献
29.
Akira Sugimoto Takeshi Kotani Junko Tsujimoto Shigeo Yoneda 《Journal of heterocyclic chemistry》1989,26(2):435-438
In order to examine the “capto-dative” substitution-effect on the electrical conductivity, five compounds which have capto-dative substituents were prepared. Electron withdrawing (capto) group was nitro- or cyano-substituted phenyl and electron donating (dative) one was 5-methyl-5,10-dihydrophenazinyl moiety. The character of intramolecular electron donor acceptor complex of the five compounds were demonstrated by their uv spectra. Electron donor acceptor complexes of them with tetracyanoquinodimethane were prepared and their electrical resistivities were measured. 相似文献
30.
Yokota K Fukushi K Ishio N Sasayama N Nakayama Y Takeda S Wakida S 《Electrophoresis》2003,24(12-13):2244-2251
We describe an application of capillary zone electrophoresis (CZE) with transient isotachophoresis (ITP) as the on-line concentration procedure for the determination of iodide in seawater. The effective mobility of iodide was decreased by the addition of 10 mM cetyltrimethylammonium chloride (CTAC) to an artificial seawater background electrolyte (BGE) so that transient ITP functioned and iodide was separated from other coexisting anions such as bromide, nitrite, and nitrate in seawater samples. After sample injection, 600 mM acetate was separately injected into the capillary as the terminating ion to generate transient ITP. The limit of detection (LOD) for iodide was 3.0 microg/L. The LOD was obtained at a signal-to-noise ratio (S/N) of 3. The values of the relative standard deviation (RSD) of peak area, peak height, and migration time for iodide were 2.9, 2.1, and 0.6%. The proposed method was applied to the determination of iodide in seawater collected around the Osaka Bay. The results obtained by use of the calibration graph were agreed with those obtained by the addition of the standard solutions for iodide. 相似文献