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151.
Yoshinori Asakawa Tsunematsu Takemoto Masao Toyota Takaaki Aratani 《Tetrahedron letters》1977,18(16):1407-1410
The stereostructures of the two new exceptional diterpene dialdehydes from the liverwort, Trichocoleopsis sacculata: sacculatal (1), responsible for the characteristic pungent taste, and isosacculatal (2) have been determined by the spectral evidence and by comparison with polygodial (3), isopolygodial (4), and drimanediol (6) of known relative configurations. 相似文献
152.
The heat capacity of 1T-TaS2 has been measured over the temperature range including the successive phase transitions (140 K–370 K) by an adiabatic calorimeter. There are three transitions in the measured temperature range, two first-order transitions (at about 226 K (T1) and about 353.5 K (T3)) and one small anomaly at about 283 K (T2) with a broad peak. The transition enthalpies are as follows; ΔH1=52±5 cal·mol-1, ΔH2=7.5±2 cal· mol-1 and ΔH3=122±8cal·mol-1. 相似文献
153.
A new optogalvanic technique with an rf discharge was applied to a high-resolution study of the Rydberg states of N2. The Ledbetter band, c4(0)1Πu ← a″(0)1Σg+, and a new visible band, c′5(0)1Σu+ ← a″(0)1Σg+, were studied at a Doppler-limited resolution of 0.05 cm?1. A Doppler-free method was also applied to resolve overlapped lines. Precise wavenumbers were determined for the rotational transitions of the two Rydberg bands. The rotational and the centrifugal constants for the lowest Rydberg state, a″(0)1Σg+, were determined to be B0 = 1.913748(42) cm?1 and D0 = 6.088(99) × 10?6 cm?1, where the numbers in parentheses are the standard deviation and apply to the last digits. 相似文献
154.
155.
The electrochemical behavior of ten nitrogen heterocycles was investigated in DMF-water and aqueous buffer solution. On the basis of these data, the effect of proton on the reduction behavior in DMF-water media and the reduction pathway in aqueous buffer solution ware phenomenologically classified. The adsorption phenomena in aqueous buffer solution and the correlation of reduction behavior with structure and reactivity were discussed. The structure of electrolytic products was also estimated and identified by negative electron density distributions of radical anion, GC-MS and spectrophotometry. 相似文献
156.
Hydroalumination of 1-alkenes with lithium aluminum hydride by catalysis of titanium tetrachloride followed by treatment with lead(IV) acetate was found to be a convenient method for the preparation of primary alkyl acetates. 相似文献
157.
Masao Shiozaki Yukiko Watanabe Toshio Kaneko Daisuke Tanaka Shin-ichi Kurakata 《Tetrahedron》2005,61(21):5101-5122
Lipid A analogues containing glucose in substitution for glucosamine on the reducing end were synthesized, and the inhibitory activities on LPS-induced TNFα production (LPS-antagonistic activity) in vitro using human whole blood cells were measured. The IC50 values (nM) of these ten compounds, 8, 14, 21, 31, 40, 51, 57, 62, 67 and 72, were 11.2, 15.4, 2.7, 0.1, 0.4, 1.3, 3.2, 3.2, 1.4 and 14.4, respectively. And also inhibitory activities (ID50) on TNFα production toward galactosamine loaded C3H/HeN mice in vivo of compounds 21, 31, 57, 62 and 67 were measured. The values of these compounds were 0.29, 0.50, 0.61, not dose-dependent and 0.33 mg/kg, respectively. 相似文献
158.
Christian?KanzowEmail author Christian?Nagel Hirokazu?Kato Masao?Fukushima 《Computational Optimization and Applications》2005,31(3):251-273
We present a successive linearization method with a trust region-type globalization for the solution of nonlinear semidefinite programs. At each iteration, the method solves a quadratic semidefinite program, which can be converted to a linear semidefinite program with a second order cone constraint. A subproblem of this kind can be solved quite efficiently by using some recent software for semidefinite and second-order cone programs. The method is shown to be globally convergent under certain assumptions. Numerical results on some nonlinear semidefinite programs including optimization problems with bilinear matrix inequalities are reported to illustrate the behaviour of the proposed method.The research of the fourth author was supported in part by a Grant-in-Aid for Scientific Research from Japan Society for the Promotion of Science. The research of the second author was supported by the DFG (Deutsche Forschungsgemeinschaft). 相似文献
159.
Masao Atoji 《Journal of solid state chemistry》1980,31(1):113-125
Polarized-light microscopic observations have shown that the birefringent, twin-domain structure of metallic sodium tungsten bronze is exhibited by Na-deficient surface films and hence is not, as had been reported elsewhere, a bulk property. The film can be synthesized by anodic electrolysis in alkaline solution. It is chemically inert, translucent, and often laminates to a multiple layer. The domain structure of the film is hypersensitive to lateral stress and to thermal variation, exhibiting a marked change at the phase transition of the substrate through apparent epitaxial coherence. The domain-wall movement is often slow enough to be visible, and the thermally induced domain modulation is occasionally accompanied by audible high-pitched sound. The bulk structure of the substrate exhibits pseudoperiodic subboundaries that are probably caused by growth defects and the segregation of the sodium atoms. The near-surface of the substrate also shows the sodium segregation that tends to precipitate in periodic patterns. Optical and morphological properties of the substrate structures exhibited no detectable change due to thermal variation or external stress. 相似文献
160.
The interaction of oxygen with a clean (110) molybdenum surface has been studied by LEED and RHEED. At room temperature two simple chemisorbed structures are found, at higher exposures a multiple order pattern is seen. At temperatures above 750 K a complex LEED pattern is observed. Initially a corresponding RHEED pattern is seen which has a different structure. Epitaxial oxide nucleation may be followed by RHEED but the initial process is not seen by LEED. More extensive epitaxial films are needed before oxide reflexions appear in the LEED pattern. The formation of an epitaxial oxide film is accompanied by the growth of {100} molybdenum facets. These may be seen after the film has been carefully evaporated away. The nuclei of oxide which form are shown by both RHEED and transmission microscopy of replicas to be characteristically shaped. 相似文献