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91.
The aim of this work was to elucidate the mode of action of calcium in calcium-inhibited ethylene biosynthesis. In one experiment, mature green tomatoes were treated with 1·5% (w/v) CaCl2+60 μM N-6(aminohexyl)-1-naphthalenesulphonamide (W5). 1·5% (w/v) CaCl2+60 μM N-6(aminohexyl)-5-chloro-1-naphthalenesulphonamide (W7), 1·5% (w/v) CaCl2 alone or distilled water (control). The control and the W7 treatment had much higher ethylene production than either the CaCl2 treatment alone or the CaCl2+W5 treatment. In another experiment, similar tomatoes were treated with 1·5% (w/v) CaCl2+15 μM trifluoperazine (TFP). 1·5% (w/v) CaCl2 only, or distilled water (control). The treatment with 1·5% CaCl2+15 μM TFP gave higher ethylene production than 1·5% (w/v) CaCl2 without TFP, and nearly the same level as the control towards the end of the experimental period. For enzyme and intermediate metabolite assays, mature green tomatoes were treated with 1·5% (w/v) CaCl2 plus either W5 or W7. W5 treatment had a lower ethylene forming enzyme (EFE) activity, higher 1-aminocyclopropane-1-carboxylic acid (ACC) concentration, similar levels of ACC synthase activity and 1-(malonylamino)-cyclopropane-1-carboxylic acid concentration, compared to the control and W7 treatment. As W7 is a more potent calmodulin antagonist than W5, these results suggest a calcium-calmodulin inactivation of EFE activity. © 1998 SCI.  相似文献   
92.
为有效提高垃圾焚烧炉安全性、经济性和稳定运行管理水平,在深入了解垃圾炉燃烧工况变化和运行人员操作经验的基础上,开发了自动燃烧控制(Auto Combustion Control,ACC)策略,主要包括主蒸汽流量、一次风流量、二次风、氧量、料层厚度及炉排和推料器速度控制。投运结果显示:机组主蒸汽流量24 h内的波动最大值为58.061 t/h,最小值为54.183 t/h,控制变化的相对标准偏差为0.85%;发电量日均值为54.10万kW•h,相对标准偏差为1.80%;供电量日均值为45.69万kW•h,相对标准偏差为2.21%,焚烧炉整体运行平稳,发电量和供电量波动较小;一个月内热灼减率统计平均值约为2.3%,相对标准偏差约为5.7%;省煤器出口含氧量24 h内的波动最大值为5.71%,最小值为2.79%,含氧量控制变化的相对标准偏差为9.66%,满足垃圾焚烧炉的运行控制要求。  相似文献   
93.
李晓宁 《计算机应用》2005,25(7):1531-1534
提出了一种基于汇聚流回推的DDoS(Distributed Denial of Setvice)综合防御方案。此方案对本地路由器上的汇聚流及其上游汇聚流回推树上第n层路由器上的汇聚流进行分布限速,以达到抵御DDoS攻击的目的。给出了汇聚流限流算法和回推汇聚流所需的反向汇聚流往返树的构建算法。汇聚流限流算法旨在最大限度地限制DDoS流,同时保护正常的用户流。反向汇聚流往返树的构建算法通过动态地探测高流量的汇聚流路径,将自动生成回推汇聚流所需的反向汇聚流往返树。  相似文献   
94.
We proposed a novel efficient operation scheme for a thermal power plant’s air-cooling system based on peak shaving, in order to cope with high ambient temperature in summer. We introduced an absorptiongeneration equipment with water/lithium working pairs into the air cooled condenser(ACC) to reconstruct the traditional thermal power plant, and established a dynamic thermodynamic model adopting Ebsilon code. We studied the thermodynamic performance variation of the reconstructed thermal power pl...  相似文献   
95.
基于ACC的制动系统模型研究   总被引:4,自引:1,他引:4  
詹军 《中国机械工程》2005,16(5):450-452,463
介绍了汽车自适应巡航控制系统的原理和特点,以及该系统对制动系统模型的要求;建立了汽车纵向动力学模型,并在此基础上建立了包括真空助力器、液压系统、制动器的整个制动系统的数学模型.该模型能满足控制的需要,并且较简单又具有较高的精度.对该模型进行了计算机模拟仿真,获得了较好仿真效果.  相似文献   
96.
97.
Phillyrin, an active constituent found in many medicinal plants and certain functional foods, has anti-obesity activity in vivo. The aim of our study was to provide new data on the molecular mechanism(s) underlying the role of phillyrin in the prevention of high glucose-induced lipid accumulation in human HepG2 hepatocytes. We found that phillyrin suppressed high glucose-induced lipid accumulation in HepG2 cells. Phillyrin strongly inhibited high glucose-induced fatty acid synthase (FAS) expression by modulating sterol regulatory element-binding protein-1c (SREBP-1c) activation. Moreover, use of the pharmacological AMP-activated protein kinase (AMPK) inhibitor compound C revealed that AMPK is essential for suppressing SREBP-1c expression in phillyrin-treated cells. Finally, we found that liver kinase B1 (LKB1) phosphorylation is required for the phillyrin-enhanced activation of AMPK in HepG2 hepatocytes. These results indicate that phillyrin prevents lipid accumulation in HepG2 cells by blocking the expression of SREBP-1c and FAS through LKB1/AMPK activation, suggesting that phillyrin is a novel AMPK activator with a role in the prevention and treatment of obesity.  相似文献   
98.
Energy‐efficient synthesis of materials locked in compositional and structural states far from equilibrium remains a challenging goal, yet biomineralizing organisms routinely assemble such materials with sophisticated designs and advanced functional properties, often using amorphous precursors. However, incorporation of organics limits the useful temperature range of these materials. Herein, the bioinspired synthesis of a highly supersaturated calcite (Ca0.5Ba0.5CO3) called balcite is reported, at mild conditions and using an amorphous calcium–barium carbonate (ACBC) (Ca1? x Ba x CO3·1.2H2O) precursor. Balcite not only contains 50 times more barium than the solubility limit in calcite but also displays the rotational disorder on carbonate sites that is typical for high‐temperature calcite. It is significantly harder (30%) and less stiff than calcite, and retains these properties after heating to elevated temperatures. Analysis of balcite local order suggests that it may require the formation of the ACBC precursor and could therefore be an example of nonclassical nucleation. These findings demonstrate that amorphous precursor pathways are powerfully enabling and provide unprecedented access to materials far from equilibrium, including high‐temperature modifications by room‐temperature synthesis.  相似文献   
99.
马韬 《电站辅机》2013,34(3):5-8
空冷岛单排管基管带材为铝钢复合材料,覆铝技术保证了翅片在成品管表面的附着力,满足碳钢管在使用期内的防腐蚀要求。采用钢铝冷轧复合技术生产单排管基材时,首先应处理带材的表面,再进行复合轧制和轧后热处理。轧制时,材料的变形量越大,就越容易被轧制复合。轧制后热处理的最佳温度,以两种金属的理论退火温度为依据,并需通过实验后确定。提高复合轧制速度后,带材间相对位置的偏移及厚度比的控制问题亟待解决。  相似文献   
100.
Recently, an ACC‐CAES generating system has been developed by applying ACC (Advanced Combined Cycle) technology to a conventional CAES (Compressed Air Energy Storage) system. The ACC‐CAES has a potential advantage of high efficiency and high capacity factor over other energy storage. However, its advantages from the viewpoints of power system operation are not fully revealed because of its peculiar operation characteristics compared with other energy storage. The characteristics include (1) it requires fossil fuel even in the case of operation using stored compressed air and (2) it has an ACC generating mode as one of its generating states to be used as a conventional ACC generating system while detaching the air storage system. Therefore, it is necessary to examine operation patterns of the ACC‐CAES and its contribution to economic operation of a power system. In order to achieve the objective, operation simulations of a power system with ACC‐CAES generating systems are needed because operation of energy storage systems such as the ACC‐CAES must be studied through an operation scheduling of a power system. This paper develops an optimal daily scheduling method of a power system with both ACC‐CAES generating systems and pumped hydro storage systems using two‐dimensional dynamic programming. Sensitivity analyses are undertaken with the developed method; the results show that ACC‐CAES generating systems tend to be operated as a peak or intermediate power source that bears some similarities to thermal plants or storage systems and, from an operation point of view, they have an economic advantage over pumped hydro storage systems. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 152(1): 15–23, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20087  相似文献   
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