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131.
132.
Analogs of methyl jasmonate (=methyl (1R*,2R*)‐3‐oxo‐2‐[(Z)‐pent‐2‐enyl]cyclopentaneacetate; MJA) bearing a cyclopropane ring, double bond, or a F‐substituent were synthesized, and their odor characteristics were examined. Most of the analogs with the same stereochemical properties as methyl epijasmonate showed odor properties superior to MJA. Interestingly, the enol acetate of MJA had a diffusive orchid‐like note. 相似文献
133.
134.
Akano T. Miura Y. Fukatsu K. Miyasaka H. Ikuta Y. Matsumoto H. Hamasaki A. Shioji N. Mizoguchi T. Yagi K. Maeda I. 《Applied biochemistry and biotechnology》1996,57(1):677-688
Applied Biochemistry and Biotechnology - Hydrogen is a clean energy alternative to the fossil fuels, the main source of greenhouse gas emissions. We developed a stable system for the conversion of... 相似文献
135.
136.
Nishikiori Hiromasa Hizumi Taisuke Kawamoto Kazuki Teshima Katsuya 《Research on Chemical Intermediates》2018,44(12):7539-7555
Research on Chemical Intermediates - A titanium metal surface was heated with an alkali metal chloride in order to produce a phase transition from amorphous titania to crystalline titania on the... 相似文献
137.
Dr. Kazuya Arashiba Prof. Hiromasa Tanaka Prof. Kazunari Yoshizawa Prof. Yoshiaki Nishibayashi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(59):13383-13389
Cycling between molybdenum(I)-dinitrogen and molybdenum(IV)-nitride complexes was investigated under ambient reaction conditions. A kinetic study of the second-order reaction rate for the conversion of the molybdenum-dinitrogen complex into the molybdenum-nitride complex indicates that the formation of the dinitrogen-bridged dimolybdenum complex is involved in the rate-determining step. DFT calculations indicate that the molybdenum-dinitrogen complex transforms into the molybdenum-nitride complex via direct cleavage of the nitrogen-nitrogen triple bond of the bridging dinitrogen ligand of the dinitrogen-bridged dimolybdenum complex. The corresponding reaction of the molybdenum-nitride complex transforming into the molybdenum-dinitrogen complex proceeds via the ligand exchange of ammonia for dinitrogen at the dinitrogen-bridged dimolybdenum complexes. A new modified reaction pathway has been proposed based on the findings of our experimental and theoretical results. 相似文献
138.
Enacyloxin IIa methyl ester in non-protic solvent gave rearranged product in acidic conditions such as surface of TLC plate of silica gel or by treatment with a catalytic amount of p-toluenesulfonic acid. On the other hand, such a rearrangement did not occur in polar protic solvent. The structure of the rearranged product was elucidated as 4-acyl analog of the cyclohexane ring. 相似文献
139.
We report on the demonstration of surface-emitted terahertz- (THz-) wave difference-frequency generation from two-dimensional (2D) periodically poled lithium niobate (PPLN). The two orthogonal periodic structures individually compensate for both the phase mismatch of the launched lasers and the generated THz wave. Tunable 1.5-1.8 THz wave generation with a bandwidth of 10-GHz was obtained by use of two 2D PPLN crystals. We also confirmed that THz waves were simultaneously generated into two opposite directions, which suggests the possibility of higher THz-wave output power. 相似文献
140.
Hiromasa Ikuta 《Thermochimica Acta》2004,414(2):227-232
The phase transition of chromium substituted lithium manganese spinel oxide, LiCryMn2−yO4 was investigated by low-temperature powder X-ray diffractometry (XRD), differential scanning calorimetry (DSC), and electrical resistivity measurements. The sample prepared at 820 °C resulted in lowering the transition temperature Tt with Cr composition y, whereas Tt of the sample prepared at 750 °C remained constant for 0≤y≤0.17 in LiCryMn2−yO4. This would be caused by a difference in distribution of the substituted Cr3+ ion in octahedral site depending on the preparation temperature. The phase transition was suppressed with increasing the amount of Cr content. 相似文献