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991.
Yukio Hirata Yukinori Kawaguchi Yasuhiro Funada Seiki Katoh 《Journal of separation science》1993,16(10):601-604
A simple inexpensive system comprising a piston pump, switching valves, and capillary tubing has been developed for preparing mixed mobile phases for capillary supercritical fluid chromatography. The system enables the on-line preparation of mixed mobile phases without contamination of the pump with modifier. Modifier concentrations, which can be changed stepwise, were determined both experimentally and theoretically, the latter on the basis of density–viscosity relationships. Examples of both isobaric and pressure programmed separations are demonstrated. 相似文献
992.
993.
Hydrosilylation of styrenes bearing β-substituents with trichlorosilane was catalyzed by a palladium complex (0.1 mol %) coordinated with (R)- 2-methoxy-2′-diphenylphosphino-1,1′-binaphthyl ((R)-MeO-MOP) to give high yields of optically active 1-aryl-1-silylalkanes (80–85% ee) as single regioisomers. The resulting silanes were readily converted into the corresponding optically active alcohols (80–99% yield). 相似文献
994.
Yasuhiro Awatsujl Nobuyuki Sakamoto Hidetoshi Utsuro Jun Tanida Yoshiki Ichioka 《Optical Review》1997,4(1):A199-A202
We present the architecture of novel optoelectronic parallel computing called optical array logic network computing (OAL-NC).
In the OAL-NC, electronic processing elements execute local operations, whereas an optical network processor is dedicated
to global operations as well as data transfer. As a prototype of the OAL-NC, a 16x16 pixel system is designed at a logical
level. Issues associated with the design task are discussed. 相似文献
995.
996.
Yasuhiro Inada Yoshihisa Nakayama Shigenobu Funahashi 《Journal of solution chemistry》2004,33(6-7):847-862
The equilibrium constants of the hydrogen-bonding interactions between the tetraaqua-beryllium(II) ion ([Be(H2O)4]2+) and water in the second solvation sphere were determined from the dependence of the 9Be NMR chemical shift (δBe) on the water concentration (C W) in propiononitrile (PN). The 9Be NMR line assigned to [Be(H2O)4]2+ is downfield shifted with the increasing C W, and the change in δBe as a function of C W is explained in terms of a two-step hydrogen-bonding interaction to form [Be(H2O)4](H2O) n 2+ (n = 1, 2). Molecular orbital calculations for [Be(H2O)4](H2O) n 2+ (n = 0?2) revealed that the electron density on the Be(II) ion increases with an increase in n due to an enhanced polarization of the bound water molecules accompanied by the hydrogen bonding in the second solvation sphere. The observed downfield shift of δBe is interpreted as a significant compensation of the diamagnetic upfield shift by the paramagnetic contribution due to the mixing of the vacant s and p orbitals of Be with the σ-type lone-pair orbitals of the coordinating water molecules. 相似文献
997.
Yasuhiro Kamitori Masaru Hojo Ry
ichi Masuda Masaki Fujishiro Isao Nakamura Katsumasa Yamamoto 《Journal of heterocyclic chemistry》1993,30(2):389-391
Several 1-(tert-butyl)-4-trifluoroacetylpyrazoles 3 were synthesized by the reaction of aldehyde tert-butylhy-drazones 2 with 4-ethoxy-1,1,1-trifluoro-3-buten-2-one ( 1 ). The tert-butyl group could be readily removed by treatment of 3 with 90% sulfuric acid. 相似文献
998.
Turbulence structure and heat and mass transfer mechanism across a wavy sheared gas-liquid interface are fluid-mechanically investigated in a wind-wave tunnel. Heat and mass transfer velocities are reported and the relationship between the scalar transfer velocities and the turbulence structure is discussed. In addition, three-dimensional direct numerical simulation is carried out to investigate the flow structure over a rigid-wavy wall similar to that over the wave. The results show that the organized motion in the air flow intermittently appears on the front side of the wave crest, and its structure is rather similar to the flow structure over the rigid-wavy wall. The organized motion in the air flow induces the organized motion in the water flow and the organized motion renews the air-water interface. The scalar transfer across a wavy sheared gas-liquid interface is controlled by the organized surface-renewal motion in the water flow 相似文献
999.
Toshihide Tsuda Akira Babazono Takanori Ogawa Hirohisa Hamada Yoshio Mino Hideyasu Aoyama Norio Kurumatani Tsuyoshi Nagira Nobuyuki Hotta Masazumi Harada Shigemi Inomata 《应用有机金属化学》1992,6(4):309-322
Human being have been using inorganic arsenic for a long time. Many reports on arsenic poisoning have been published: eg case reports, examination reports, post mortem reports, and epidemiological studies. Several aspects and features of arsenic poisoning are discussed in this report. Methods of inferring arsenic-related disease, disease classification according to acute or chronic criteria, exposure route, interaction, confounding factors, and the oxidation state of arsenic are all discussed. The effects of arsenic are classified into skin, respiratory system, gastrointestinal tract, liver, cardiovascular system, nervous system, and bone marrow effects. Carcinogenicity is an important chronic effect of arsenic poisoning, so special attention is paid to it in this review. In Japan, there have been many incidents of arsenic poisoning. In this review, we often use data from these cases, such as the Morinaga powdered-milk poisoning case, the Ube soy-sauce poisoning case, the Toroku mine incident, and the Nakajo well-water poisoning case. We emphasize here the necessity of planning follow-up studies and total health care for patients exposed to arsenic. 相似文献
1000.