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排序方式: 共有53条查询结果,搜索用时 62 毫秒
1.
 研究开发出一种遥操作工程机器人系统,可以应用于诸如火灾现场的修复作业等广阔的领域.该系统由伺服控制的工程机器人、2根从远处操纵工程机器人的操纵杆、视频系统和6自由度运动模拟器组成.操作者坐于座椅上,座椅固定于运动模拟器的上方. 该系统需要解决的一个关键问题是如何使操纵者高质量地获得工作现场的临场运动感觉. 提出了一种6自由度临场运动感觉反馈方法,其信号源来自工程机器人上安装的6个加速度传感器. 该方法的有效性已为实验所证明,即应用6自由度运动模拟器不但可以高质量地模拟工程机器人单个自由度的运动:滚动、俯仰、转动以及前后、左右、上下的平移,而且可以高质量地模拟工程机器人的各种复合运动.  相似文献   
2.
A high repetition rate, wide-aperture KrF laser with a magnetic switch has been developed. A dynamic response and a core loss of several magnetic materials were measured, resulting in a loss as low as 0.45 J/pulse for a voltage risetime of ~100 ns. A maximum output energy of 2.5 J in 20 ns (FWHM) was obtained with a total efficiency of 2.5% at 20 Hz. The cross section of the output beam was 65×50 mm2. Spectral, spatial, and temporal profiles of gain and absorption coefficients were also measured, resulting in a peak gain of 8.5%/cm. An output energy of 410 mJ was extracted in 280 fs with two beams by using this laser as an amplifier  相似文献   
3.
The authors have been studying Chemical Heat Pumps (CHP) from the viewpoints of energy saving and environmental impact. The CHP can store thermal energy in the form of chemical energy by an endothermic reaction, and release it at various temperature levels during heat demand periods by exo/endothermic reactions. The authors have proposed in an earlier study a novel chemical heat pump (CHP) system for environmentally-friendly effective utilization of thermal energy in drying as a chemical heat pump dryer (CHPD). In this exploratory study, we test the effectiveness of operating the proposed CHPDs experimentally. Basic experiments on the CHPDs such as hot dry air production for convective drying are performed on lab-scale CHPD apparatuses using gas-solid reactions in calcium oxide/calcium hydroxide reactant beds. The proposed CHPDs are found to produce hot air by CHP operation for drying. The temperature levels of the produced hot air and the reaction rates/conversions are as good as in the case of hot water supply system using basically same CHP operation. The cold heat for air dehumidification is also found to be generated/recovered by the same CHPD system. The generated heat amounts can be increased by changing the operating conditions although the heat recovery must be enhanced for practical application of CHPDs.  相似文献   
4.
The iron(III) chloride‐catalyzed Friedel–Crafts arylation of 4‐aryl‐4‐methoxy‐2,5‐cyclohexadienones, which were easily prepared by the phenyliodine(III) diacetate (PIDA)‐mediated oxidation of 4‐arylphenols in methanol, proceeded site‐selectively to form meta‐terphenyl (2,4‐diarylphenol) derivatives in good yields. The subsequent PIDA‐mediated oxidation and iron(III) chloride‐catalyzed Friedel–Crafts arylation of the resulting products gave the corresponding 2,4,6‐triarylphenol derivatives. The present method provides useful highly substituted polyarylated compounds.

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5.
To provide a spatially homogeneous and sufficiently high-voltage discharge, the laser described here used LC inversion and two-stage magnetic pulse compression in the excitation circuit and used UV radiation for pre-ionization. It also employed one commercial thyratron as a high-voltage switch. Evaluation of the dynamic magnetic characteristics of four magnetic materials in a magnetic pulse compression circuit showed that the Fe-based nanocrystalline soft magnetic alloy was the best core material for a compact switch with low core loss. At a 10 Hz repetition rate the maximum output energy obtained in a 80×60 nm discharge cross section and in 70 ns pulses (FWHM) was 6.2 J  相似文献   
6.
The chemoselective hydrogenation of unsaturated bonds and azide functionalities is achieved in the presence of nitro groups by a heterogeneous palladium catalyst supported on molecular sieves (MS3A). The present method shows a wide‐range of applicability with regard to substrates and the catalyst can be easily prepared and reused at least three times without any loss of activity.  相似文献   
7.
Zhang  Lan  Lu  Jian  Nogami  Hirofumi  Okada  Hironao  Itoh  Toshihiro  Arai  Shozo 《Microsystem Technologies》2018,24(1):457-463
Microsystem Technologies - During the growth of Japanese cows, the ruminal pH value is an important physiological parameter, which remarkably affects their nutritional status. To monitor the health...  相似文献   
8.
Currently, pyripyropene A, which is isolated from the culture broth of Aspergillus fumigatus FO‐1289, is the only compound known to strongly and selectively inhibit the isozyme sterol O‐acyltransferase 2 (SOAT2). To aid in the development of new cholesterol‐lowering or anti‐atherosclerotic agents, new A‐ring simplified pyripyropene A analogues have been designed and synthesized based on total synthesis, and the results of structure–activity relationship studies of pyripyropene A. Among the analogues, two A‐ring simplified pyripyropene A analogues exhibited equally efficient SOAT2 inhibitory activity to that of natural pyripyropene A. These new analogues are the most potent and selective SOAT2 inhibitors to be used as synthetic compounds and attractive seed compounds for the development of drug for dyslipidemia, including atherosclerotic disease and steatosis.  相似文献   
9.
10.
From the viewpoints of energy savings and environmental impacts, the authors have been studying on Chemical Heat Pump (CHP) systems such as a calcium sulfate/water reaction system for effective waste energy utilization. The CHP system using hydration of CaSO4/dehydration of CaSO4·1/2H2O reaction can use low-temperature level thermal energy effectively in many processes. The reaction material CaSO4 is prepared from original material: gypsum (CaSO4·2H2O). Although the natural gypsum is used in many fields; an enormous amount of resources has become waste. We are trying to solve the problems of the energy consumption, environmental pollution and waste material at the same time by the CHPs using CaSO4·1/2H2O hydration/dehydration reaction.More studies on the reaction characteristics of various CaSO4 materials are necessary for the CHP reaction system in different conditions. We examined the hydration/dehydration conversions, reaction rates etc. of several CHP materials. We prepared two types of original particles. The one (A) is a just crushed natural gypsum (710–1000 μm), and the other (B) is a granulated same size particles by fine particles (<10 μm).As a result, the changes of conversion and reaction rate showed some differences. It was probably caused by impurities in the gypsum to some extent. The impurities may have affected the stability of the data and the final conversions etc. The hydration conversions of CaSO4 from the natural gypsum which contains some of impurities such as Thailand one were lower than 85%, and the conversions of the natural gypsum which contains fewer impurities such as Australia or Morocco one were higher than 90%. The granulated particle (B) has some effect of adsorption because of the wider specific surface area. We need to design the reaction materials from the viewpoints of the purity and the heat/mass transfer characteristics in order to meet the chemical heat pump performance.  相似文献   
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