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排序方式: 共有270条查询结果,搜索用时 234 毫秒
231.
Masahiko Tani Yuichi Hirota Christopher T. Que Shigehisa Tanaka Ryo Hattori Mariko Yamaguchi Seizi Nishizawa Masanori Hangyo 《International Journal of Infrared and Millimeter Waves》2006,27(4):531-546
The photoconductive (PC) antenna is a key device for the recent terahertz (THz) photonics based on laser-pumped generation
and detection of THz radiation. In this paper we report on two new types of PC antennas: the Schottky PC antenna and the multi-contacts
PC antenna. The former one is able to detect THz radiation intensity without the time-delay scan and useful for applications
where spectroscopic information is not important, such as the THz intensity imaging. The latter one is useful for the polarization
sensitive THz spectroscopy, such as the THz ellipsometry. The characteristic features of these new types of PC antennas are
studied by using a THz time-domain spectroscopy system. 相似文献
232.
Quantum chemistry beyond Born–Oppenheimer approximation on a quantum computer: A simulated phase estimation study 下载免费PDF全文
Libor Veis Jakub Višňák Hiroaki Nishizawa Hiromi Nakai Jiří Pittner 《International journal of quantum chemistry》2016,116(18):1328-1336
We present an efficient quantum algorithm for beyond‐Born–Oppenheimer molecular energy computations. Our approach combines the quantum full configuration interaction method with the nuclear orbital plus molecular orbital method. We give the details of the algorithm and demonstrate its performance by classical simulations. Two isotopomers of the hydrogen molecule (H2, HT) were chosen as representative examples and calculations of the lowest rotationless vibrational transition energies were simulated. © 2016 Wiley Periodicals, Inc. 相似文献
233.
234.
K. Kamiyama D. Shiomi S. Hase M. Nishizawa K. Sato M. Kozaki K. Okada T. Takui 《Applied magnetic resonance》2000,19(1):45-57
A crystal-engineering approach to organic ferrimagnets is reported. Coulombic energy between an anionic biradical withS = 1 and a cationic monoradical withS = 1/2 can be utilized as a driving force of cocrystallization of open-shell molecules with different spin quantum numbers,
leading to organic salt ferrimagnets. In this study, 3,5-substituted phenol and benzoic acid derivatives of nitronyl nitroxide
biradicals were synthesized as an ionizableS = 1 component of organic salt ferrimagnets. The molecular ground states of the biradicals in the neutral state were examined
by continuous wave electron spin resonance (ESR) spectroscopy and static paramagnetic susceptibility measurements in the solid
state. The molecular ground state of the phenol derivative was found to be triplet (S = 1) with the singlet-triplet energy gap of ΔE/kB ≈ 25 K, indicating that the biradical can be a building block of organic salt ferrimagnetics. The benzoic acid derivative
was found to have a singlet (S = 0) ground state (ΔE/kB
≧ −5 K), exemplifying thatmeta-(3,5)-linkage of unpaired electrons in π-aromatic rings does not necessarily give a triplet ground state for heteroatomic-substituted
π conjugation. The molecular ground states of the biradicals determined in the ESR experiments were confirmed by the susceptibility
in the solid state. 相似文献
235.
Nearly perfect crystals of III–V compounds are grown by a new LPE method which can produce homogeneous and high-quality crystals with controlled stoichiometry. Homogeneous epitaxial growth is performed at fixed temperature with a temperature difference in a melt, under controlled vapour pressure of the group V elements. In the experiment, the fluctuation of growing temperature is ascertained to produce a number of new defects and the effect of controlled vapour pressure is investigated. It has been ascertained that an optimum vapour pressure, which is the function of growing temperature, can suppress the generation of “rooty faults” to a minimum density. There is close agreement between the optimum vapour pressure in the heat treatment of crystals to reduce the generation density of lattice defects and the optimum vapour pressure to obtain defect-free crystals in the process of crystal growth. The epitaxial layers prepared under optimum vapour pressure have the highest mobility and the lowest additional carrier concentration. The lattice constant of the epitaxially grown crystal under controlled vapour pressure also shows a minimum value at optimum pressure. This also shows that the controlled vapour pressure is important in lattice fitting of epitaxial layers. The epitaxial layers grown by the temperature difference method (TDM) under optimum control of the vapour pressure (CVP) are almost as perfect crystallographically as measured by X-ray topography. The experiments are performed for GaP and GaAs. 相似文献
236.
Jun-ichi Nishizawa Yasuo Okuno Ken Suto Toshio Sato Shigenobu Yamokoshi 《Solid State Communications》1974,14(10):889-892
Annealing effect of GaP depends on the phosphorus pressure observed by Hall effect, X-ray diffraction and photoluminescence. The phosphorus pressure for the peaks of the lattice constant after annealing coincide with that for the high resistivity in the Hall measurement. 相似文献
237.
238.
Mugio Nishizawa Hidetoshi Yamada Setijati Sastrapradja Yuji Hayashi 《Tetrahedron letters》1985,26(12):1535-1536
The structure of an unsymmetrical dimeric sesquiterpene named bicalamenene has been established based on the spectral study and synthesis. 相似文献
239.
240.
Y Suzuki A Kobayashi T Nishizawa H Inagawa A Morikawa G Soma D Mizuno 《Chemical & pharmaceutical bulletin》1992,40(5):1266-1267
An oral administration of partially purified LPSw, a lipopolysaccharide (LPS) from wheat flour, at a concentration of 20 ng/ml in drinking water beginning 1d after infection significantly decreased mouse mortality and prevented animal weight loss in acute infection with Toxoplasma gondii. Whereas 71% (5/7) of mice in a control group that did not receive LPSw died of toxoplasmosis, only 14% (1/7) of mice treated with LPSw died (p less than 0.05). The administration of LPS purified from Bordetella pertussis also significantly decreased the mortality of infected mice. LPS from Escherichia coli and synthetic lipid A (LA-15-PP(506)), however, did not show a significant decrease in mortality. 相似文献