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991.
This paper describes the development of fully-automated synthesis systems for preparing and isolating various kinds of pharmaceutical compounds. The systems are versatile, and are able to perform most of the chemical reactions currently used in organic chemistry, with the exception of hydrogenation which requires high pressure. An additional benefit is the very user-friendly software.  相似文献   
992.
This paper presents new block diagrams for induction and synchronous motors with stator core losses such as eddy‐current and hysteresis losses. The proposed block diagrams succeed in realizing simple and clear configurations with physically meaningful vector signals, which are helpful for understanding motor electromagnetic mechanism and useful for designing controllers for them. Vector signals, which are defined in the general reference frame, are utilized as transfer signals between blocks. The proposed vector‐signal block diagram in the frame can be directly and easily reduced to the one in such a specific frame as a stationary or synchronous frame simply by adding certain constraints to it. Shown are three configurations for induction motor, two for synchronous motors including permanent magnet cylindrical motor, permanent magnet salient‐pole motor, and reluctance motor. © 2001 Scripta Technica, Electr Eng Jpn, 138(2): 59–70, 2002  相似文献   
993.
Effects of co-existence of H2O, CO2, and SO2 in the reaction gas on the catalytic performance of cobalt containing silicate having ZSM-5 (MFI) structure (Co-silicate) were studied. Water vapor retarded only the hydrocarbon conversion to CO2 but no effect was observed on NO conversion. Addition of CO2 or SO2 did not affect the reaction. The stability of H-Co-silicate against H2O, CO2, and SO2 was ascribed to the state of metallic active species which were stabilized by incorporation into the high siliceous MFI structure.  相似文献   
994.
感光性丙烯腈共聚物超滤膜的制备   总被引:1,自引:0,他引:1  
以感光性单体和丙烯腈共聚合成了共聚物膜材料,并制备出具有光敏特性的超滤膜;扫描电子显微镜图像显示所制备的高聚物膜具有超滤结构;膜的透过实验表明,所制备的膜具有较高的纯水通量及对蛋白质截留率,并初步探讨了铸膜液浓度对膜性能的影响.  相似文献   
995.
This paper proposes a new current control method for energy‐efficient and/or wide‐speed‐range drive of salient‐pole permanent magnet synchronous motors. The proposed method is distinguished from conventional ones by the following features. (1) The original command is a signed current norm. (2) The exact d‐axis and q‐axis current commands that perform energy‐efficient and/or wide‐speed‐range drive are analytically and simply determined from the singed current norm command. (3) For speed control mode, the system turns out to be nonlinear, but its stability can be guaranteed based on Popov's stability theorem. (4) It can be applied for a mode similar to torque control. (5) Current limitation can be carried out accurately but very simply. Concrete analytical d‐axis and q‐axis current commands are presented, which satisfy exactly one of three optimum current control codes such as maximum torque, maximum power factor, and voltage limitation. A design method for PI speed controller that guarantees system stability is also presented. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 161(3): 66–77, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20305  相似文献   
996.
This paper proposes and analyzes a new simple real‐time phase‐estimation method for single‐phase signals, which is based on a vector mapping theory of n‐dimensional to 2‐dimensional vectors. According to the analyses, the proposed mapping method can estimate instantly and properly the true phase of the signals that are contaminated by significant amplitude of noise and harmonics. The mapping method contains the conventional DFT method as a special case. In other words, it can be treated as a generalization of the DFT. Several simple realizations of the mapping method are also newly proposed as a single‐input and two‐output digital mapping filter in both nonrecursive and recursive forms. The recursive realization being able to decrease drastically computing load utilizes the normal form that is robust to finite word length effects. As an application of the proposed mapping method, inverter‐using power control system connected with a single‐phase grid is shown. All analytical results are verified by numerical experiments and the usefulness of the newly proposed mapping method is confirmed. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 160(1): 27–38, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20263  相似文献   
997.
This study examined whether universality of the 5-factor model (FFM) of personality operationalized by the Revised NEO Personality Inventory is due to genetic influences that are invariant across diverse nations. Factor analyses were conducted on matrices of phenotypic, genetic, and environmental correlations estimated in a sample of 1,209 monozygotic and 701 dizygotic twin pairs from Canada, Germany, and Japan. Five genetic and environmental factors were extracted for each sample. High congruence coefficients were observed when phenotypic, genetic, and environmental factors were compared in each sample as well as when each factor was compared across samples. These results suggest that the FFM has a solid biological basis and may represent a common heritage of the human species. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
998.
Linear and nonlinear torsional behavior of unidirectional CFRP and GFRP   总被引:1,自引:0,他引:1  
The helicopter bearingless rotor flexbeam is usually made of glass-fiber reinforced plastic composite (GFRP). Carbon-fiber composites (CFRP) are candidate for future flexbeam materials due to their superior tensile fatigue strength. This research examines the feasibility of CFRP as a future flexbeam material. The torsion behaviors of unidirectional CFRP and GFRP with the same matrix resin were investigated. As a result, it was confirmed that the behavior of both CFRP and GFRP is comprised of linear/nonlinear domains. The initial torsional rigidity of CFRP was almost the same as that of GFRP. The torsional rigidities calculated from Lekhnitskii’s equations agreed with the experimental results, and they are mainly determined by the shear stiffness of the materials. The nonlinear torsional behavior was observed above 0.5% of the shear strain, and it is due to plastic deformation of the matrix resin. A 3D plasticity model proposed by Sun et al. was applied to the plasticity parameters obtained from off-axis tensile tests. The numerical curves agree with the experimental data below 1.5% of the shear strain. The experimental result suggests that GFRP can be replaced by CFRP as torsional elements of a helicopter flex beam without an increase in torsional rigidity.  相似文献   
999.
某铀尾矿库周边地区氡调查   总被引:4,自引:0,他引:4  
采用中国的KF606氡累积探测器的日本的MK-Ⅱ氡/tu累积探测器,对某尾矿库周边地区空气中氡浓度的范围,氡浓度的方位分布和距离人布等进行了调查,调查历时1年,每个测量点同时采用这两种仪器,文中还介绍了中日仪器之间氡测量平行样的长期比对结果。  相似文献   
1000.
Reports an error in "Substance and artifact in the higher-order factors of the Big Five" by Robert R. McCrae, Shinji Yamagata, Kerry L. Jang, Rainer Riemann, Juko Ando, Yutaka Ono, Alois Angleitner and Frank M. Spinath (Journal of Personality and Social Psychology, 2008[Aug], Vol 95[2], 442-455). In this article, an incorrect DOI was published. The correct DOI for this article is 10.1037/0022-3514.95.2.442. (The following abstract of the original article appeared in record 2008-09787-013.) J. M. Digman (1997) proposed that the Big Five personality traits showed a higher-order structure with 2 factors he labeled α and β. These factors have been alternatively interpreted as heritable components of personality or as artifacts of evaluative bias. Using structural equation modeling, the authors reanalyzed data from a cross-national twin study and from American cross-observer studies and analyzed new multimethod data from a German twin study. In all analyses, artifact models outperformed substance models by root-mean-square error of approximation criteria, but models combining both artifact and substance were slightly better. These findings suggest that the search for the biological basis of personality traits may be more profitably focused on the 5 factors themselves and their specific facets, especially in monomethod studies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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