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传统的COD测量方法需要消耗大量的化学试剂,容易对环境产生二次污染,测试成本高,而且难以实现在线自动检测。是能公司研制的全光谱法COD在线水质监测仪可在无人干预的情况下完成自动清洗、测试和数据处理等操作,本文将从用户的角度对其各方面性能进行考察,实际测量了烟台市内的部分湖水和河水样品,并与实验室的测试结果进行对比。实验结果证明,该仪器无需任何化学试剂,线性范围宽(0~160 mg/L),检出限低(0.36 mg/L),测定速度快(30 s/样),精密度好,满足国内在线检测仪器的各项指标,可以实现在线实时监测。 相似文献
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In the HL-2A 2004 experiment campaign, pulsed molecular beam injection (MBI) and strong hydrogen gas puffing under the divertor configuration were used for gas fueling. The experimental results show that the MBI of hydrogen can reduce the heat flux to the divertor target plate. The electron temperature measured by the Langmuir probe array decreases significantly during the injection of the molecular beam whereas the electron density increases. This indicates that the plasma pressure near the target plates tends to be constant at a new equilibrium level. In the divertor plasmas with strong hydrogen gas puffing a high plasma density up to 4.4 × 10^19 m^-3 was achieved. In addition, a phenomenon similar to the partially detached divertor regime was observed, which is being studied in open divertor tokamaks such as DIII-D to reduce the peak heat flux on the target plates near the separatrix. After a strong gas puffing the electron temperature measured on the outer divertor target plate near the separatrix decreases till below 5 eV or even lower, but that of the farther outer divertor target plate does not change obviously; and the CIII and the Ha emissions at the plasma edge decrease as expected, but the Ha emission near the Xpoint increases. These results reflects some interesting characteristics, which needs to be studied by further modeling and experiments. 相似文献
86.
电力电缆因具有占地面积少、线路损耗小等优点而被广泛应用于电力传输领域,其绝缘性能对供电可靠性有着极其重要的影响。在电场、温度、应力等因素的作用下,电力电缆及终端接头不可避免地会出现绝缘缺陷,劣化修复技术主要是在缺陷出现后能够快速、准确地对绝缘缺陷进行修复的方法。对此,阐述了电力电缆及终端接头的劣化原因,介绍了温度、机械应力、施加电压、空间电荷注入、污秽积累等因素对电力电缆及终端接头劣化的影响机理及规律。总结了目前常见的电力电缆及终端接头的修复技术并说明了各自的应用范围和优缺点,并针对电缆劣化机理、劣化修复技术和终端接头修复技术等方面提出相关建议。 相似文献
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The arrangement of the neutral beam line in HL-2A tokamak is introduced. Attenuation of neutral beam injection is analyzed numerically under different plasma conditions: different plasma densities, beam energies, electron temperatures, and impurity concentrations. Both optimized plasma density and beam energy for plasma heating are obtained. 相似文献
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K. TOI S. OHDACHI F. WATANABE K. NARIHARA T. MORISAKI 高翔 M. GOTO K. IDA S. MASUZAKI K. MIYAZAWA S. MORITA S. SAKAKIBARA K. TANAKA T. TOKUZAWA K.W. WATANABE 严龙文 M. YOSHINUMA 《等离子体科学和技术》2006,8(1):5-9
On the Large Helical Device (LHD) where nested magnetic surfaces are surrounded by the ergodic field layer, edge transport barrier (ETB) was produced in neutral-beam-injection (NBI) heated plasmas through transition and non-transition processes. The former case is the ETB formation by L-Htransition, where characteristics of L-H transition observed in a tokamak plasma are clearly recognized. The confinement improvement is the modest (- 10%), compared with the ISS95 international stellarator scaling. The threshold power for the transition is comparable or slightly lower than the ITER scaling law established by tokamaks and compact tori. The ETB is formed inside the ergodic field layer of the vacuum field. The ETB formation destabilizes edge coherent modes such as m/n = 1/1, 2/3 and 1/2, of which rational surfaces are in the magnetic hill. The formed ETB is partially and transiently destroyed by these coherent edge MHD modes and edge localized modes (ELMs) typically observed in Ha signals. The latter ETB is observed in a plasma with large reversed NBI-driven current more than 100 kA at Bt = 1 T. In these plasmas, the edge magnetic shear is enhanced by the current and the rotational transform in the core region is expected to be appreciably reduced. Thus reduced rotational transform in the plasma central region will enhance outward heat and particle fluxes toward ergodic edge layer. The ETB with steep electron temperature gradient up to - 5 keV/m is formed by blocking enhanced outward heat flux. 相似文献