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91.
Uchiyama N Matsunaga K Kiuchi F Honda G Tsubouchi A Nakajima-Shimada J Aoki T 《Chemical & pharmaceutical bulletin》2002,50(11):1514-1516
Trypanocidal constituents of dried leaves of Laurus nobilis L. (Lauraceae) were examined. Activity-guided fractionation of the methanol extract resulted in the isolation of two guaianolides, dehydrocostus lactone (1) and zaluzanin D (2), and a new p-menthane hydroperoxide, (1R,4S)-1-hydroperoxy-p-menth-2-en-8-ol acetate (3). The minimum lethal concentrations of these compounds against epimastigotes of Trypanosoma cruzi were 6.3, 2.5, and 1.4 microM, respectively. 相似文献
92.
Secondary 2-thiophenecarboxamides efficiently undergo unique triarylation accompanied by formal decarbamoylation under palladium catalysis. 3-Substituted thiophenes, especially having an electron-withdrawing group, can also be triarylated. 相似文献
93.
We study the size dependence of the nonlinear response of weakly confined excitons for the size region beyond the long wavelength approximation regime. The observed degenerate-four-wave mixing signal of GaAs thin layers exhibits an anomalous size dependence, where the signal is resonantly enhanced at a particular thickness region. The theoretical analysis elucidates that this enhancement is due to the size-resonant enhancement of the internal field with a spatial structure relevant to the nondipole-type excitonic state. These results establish the formerly proposed new type of size dependence of nonlinear response due to the nonlocality induced double resonance. 相似文献
94.
Assuming that the effective magnetic moment operator is expressed in terms of one- and two-body operators which are not explicity specified, we study relations among magnetic moments and M1 rates in single-closed-shell nuclei. 相似文献
95.
96.
Okio Nomura 《International journal of quantum chemistry》1980,18(1):143-150
Global features of potential-energy curves are drawn using minimal basis SCF –CI method. Potential-energy surfaces are drawn at points of interest. The mechanism of the chemiluminescence is discussed along with the measurement of a rate constant exploiting the phenomena. 相似文献
97.
The α-decay properties of very short-lived N = 128 isotones, 216Ra, 217Ac and 218Th, were investigated by the pulsed-beam method. Alpha emitters of interest were produced in the bombardment of 208Pb or 209Bi with 65–96 MeV 12C or 14N ions and α-decays were measured between natural beam bursts of the cyclotron. The results obtained are Eα = 9.349±0.008 MeVand and and . The experimental reduced α-widths of N = 128 isotones from 212Po to 218Th are shown to agree well with the simple shell model calculation. 相似文献
98.
Takahiko Ishiguro Ei-ichiro Suzuki Akiko Y. Hirakawa Masamichi Tsuboi 《Journal of Molecular Spectroscopy》1980,83(2):360-372
Raman spectra of thiourea have been observed in H2O and D2O solutions with the exciting laser beams of 514.5, 488.0, 457.9, 363.8, 325.0, and 257.3 nm. The resonance Raman excitation profile of the 729-cm?1 line has been examined in the region of the 237-nm absorption band () by use of a solvent shift of the absorption band instead of by changing the wavelength of the exciting beam. The depolarization degree of this line was measured and its overtone Raman line was also observed. On the basis of the results of these experiments, it has been concluded that the 729-cm?1 Raman line, assignable to the CS stretching vibration, derives its intensity solely from the 237-nm band when it is excited at 257.3 or 325.0 nm. On exciting in the region 363.8–514.5 nm, however, contributions of the higher-frequency bands are predominant rather than the contribution from the 237-nm band. The Raman line at 1520 cm?1 of thiourea-d4 is assignable to the NCN antisymmetric stretching vibration. From its excitation profile, its intensity has been considered to come from a vibronic coupling between the excited electronic states of the 220-nm () and the 197-nm () bands. 相似文献
99.
100.
Inoue Y Nomura Y Nakaoka T Watanabe M Kiryu S Okubo T Ohtomo K 《Magnetic resonance imaging》2005,23(5):641-645
The aim of this study was to investigate the effect of temporal resolution on the estimation of left ventricular (LV) function by cardiac magnetic resonance (MR) imaging using a steady-state free precession (SSFP) sequence. Left ventricular function was assessed by cine MR imaging using a segmented SSFP sequence in 10 healthy volunteers. Views per segment (VPS) were set at 8 and 20, resulting in high and low true temporal resolution, respectively. Irrespective of VPS, images were reconstructed at 40 cardiac phases, providing high apparent temporal resolution. Data were analyzed using 40, 20 and 10 phases to simulate different apparent temporal resolutions. Increasing the cardiac phases used for analysis slightly decreased mean end-systolic volume (ESV) and slightly increased mean ejection fraction (EF). No substantial difference in estimates of end-diastolic volume (EDV) was found between VPSs of 8 and 20. Imaging with a VPS of 20 yielded a larger ESV and smaller EF than imaging with a VPS of 8 when 40 phases were used. In conclusion, low true temporal resolution causes overestimation of ESV and underestimation of EF. Improvement of apparent temporal resolution mildly reduces but does not eliminate the errors caused by low true temporal resolution. 相似文献