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991.
A facile one‐step process for the fabrication of hybrid ZnO–dye hollow spheres with novel optical properties has been discovered. Addition of Evans blue (EB) dye to cetyltrimethylammonium bromide (CTAB) results in the formation of CTAB‐EB micelles through an ionic self‐assembly process, and the resulting material acts as a soft template for the crystallization of ZnO upon addition of a zinc salt and ammonia under mild refluxing conditions. The formation mechanism of such hollow spheres has been investigated. These new hybrid ZnO–dye hollow spheres display distinct optical properties that differ from properties observed for the pure ZnO and dye components. This approach is a new and effective method for fabricating novel semiconductor–dye hybrids with unique electronic and optical properties and is expected to provide access to additional inorganic–organic materials with novel structures and unusual functionalities. 相似文献
992.
S. Xiong B. Xi C. Wang D. Xu X. Feng Z. Zhu Y. Qian 《Advanced functional materials》2007,17(15):2728-2738
Semiconductor ZnS with novel and complex 3D architectures such as nanorods (or nanowires) networks, urchinlike nanosturctures, nearly monodisperse nanospheres self‐assembled from nanorods and 1D nanostructures (rods and wires) had been synthesized in a binary solution by controlling the reaction conditions, such as the volume ratio of the mixed solvents and the reaction temperature. The morphology of ZnS changed from 3D architectural structures to 1D rodlike (or wirelike) shape when the temperature was increased from 160 to 200–240 °C. The possible growth mechanisms for the formation of nanospheres self‐assembled from nanorods are tentatively discussed according to the experimental results. The photocatalytic activity of various ZnS nanostructures has been tested by degradation of acid fuchsine under infrared light compared to that of commercial ZnS powders under infrared‐light irradiation and commercial TiO2 powders under UV‐light irradiation, indicating that the as‐obtained ZnS nanostructures exhibit excellent photocatalytic activity for degradation of acid fuchsine. 相似文献
993.
994.
Michiaki Yamasaki Naoyuki Hayashi Shogo Izumi Yoshihito Kawamura 《Corrosion Science》2007,49(1):255-262
Rapidly solidified flaky powder metallurgy (RS FP/M) processing was applied for preparation of corrosion-resistant bulk Mg alloys with Zn and rare earth elements. The corrosion behavior of the melt spun Mg-Zn-La and Mg-Zn-Yb alloy ribbons in 1% NaCl solution was investigated in order to determine optimum composition of corrosion-resistant Mg alloys. The effect of heat-treatment on the corrosion behavior of RS Mg-Zn-La and Mg-Zn-Yb alloys also was studied. In the Mg-Zn-La alloys, as-quenched alloys showed good corrosion resistance in the NaCl solution, but heat-treatment led to degradation due to microstructure change, that is, reduction in dispersion of the Mg17La2-type intermetallic compound. In the Mg-Zn-Yb alloys, both as-quenched and heat-treated Mg97.5Zn0.5Yb2 alloys exhibited low corrosion rates because fine distribution of Mg2Yb-type intermetallic compound in α-Mg matrix was not largely changed by heat treatment. 相似文献
995.
介绍了钢管热镀锌用160t电阻加热炉的特点,主要设计参数和如何选择锌锅材质、壁厚等。简要说明了炉温的控制方法及炉体存在的不足之处。多年生产实践证明,由于锌锅锅体尺寸和材质及壁厚选择比较合理,锌液的温度均匀,从而延长了锌锅的使用寿命。 相似文献
996.
Kunitsugu Aramaki 《Corrosion Science》2002,44(6):1361-1374
It has been reported that cerium(III) chloride CeCl3 and sodium octylthiopropionate C8H17S(CH2)2COONa (NaOTP) are effective inhibitors for zinc corrosion in 0.5 M NaCl. In this study, synergistic inhibition of zinc corrosion in an aerated 0.5 M NaCl solution by a mixture of these inhibitors was investigated by polarization measurements after immersion of a zinc electrode in the solution for many hours. The inhibition efficiency of 1×10−4 M CeCl3 plus 1×10−5 M NaOTP mixture was high, 95.1% after both 3 and 120 h. X-ray photoelectron spectroscopy and electron-probe microanalysis for the inhibited electrode revealed that the zinc surface was covered with a protective film composed of an hydrated or hydroxylated Ce-rich oxide, a small amount of Zn(OH)2 and a trace of Zn(OTP)2 chelate. The inhibition effect of 1×10−5 M NaOTP in the NaCl solution for the zinc electrode previously treated in 1×10−3 M CeCl3 for 30 min was also examined, indicating a higher inhibition efficiency, 96.3% after immersion of the electrode in the solution for 120 h. 相似文献
997.
On the pitting corrosion currents of zinc by chloride anions 总被引:1,自引:0,他引:1
E.E. Abd El Aal 《Corrosion Science》2004,46(1):37-49
The changes in the pitting corrosion current density with time on zinc electrode concerning the concentration of both the passivating borate and the aggressive chloride anions were followed using a simple electrolytic cell. The pitting corrosion currents started to flow after an induction period, τ. This period is found to be a function of the concentration of Cl− anion, according to the relation logτ=β−γlogCCl−. The pitting corrosion currents finally reached a steady-state value, which depended on the concentration of both B4O72− and Cl− anions. At a constant B4O72− anion concentration, the pitting corrosion current varied with the concentration of Cl− anion according to the relation logipit=a1+b1logCCl−. It also varies at constant Cl− anion concentration and various B4O72− anion concentration according to the relation logipit=a2−b2logCB4O72−. The susceptibility of the passivating zinc to pitting corrosion was found to be increasing as the temperature and pH of the solution increases. Results are discussed on the basis of adsorption of the aggressive anion on the passivating film, followed by penetration through the film and incorporation in it. This undermines the oxide film and causes pitting corrosion. 相似文献
998.
Tunç Tüken 《Surface & coatings technology》2006,201(6):2782-2790
Polypyrrole (PPy) films (∼ 1.7 μm thick) have been electrodeposited on mild steel (MS) substrates from 0.1 M pyrrole containing aqueous oxalic acid solution, by using cyclic voltammetry technique. Then, the polymer coatings were modified with deposition of zinc particles (∼ 1 mg/cm2), at a constant potential value of − 1.20 V in 0.2 M ZnSO4 solution. The corrosion performance of zinc modified PPy coating has been investigated in 3.5% NaCl solution, by using electrochemical impedance spectroscopy and anodic polarisation curves. Also, the corrosion behaviours of zinc modified PPy coated platinum and single PPy coated MS samples have been investigated, for comparison. It was shown that zinc modified coating exhibited very low permeability and provided important cathodic protection to MS for considerably long immersion period. The voluminous zinc corrosion products are formed during exposure time in aggressive solution, giving rise to a blocking effect on the porous structure and led to effective barrier behaviour of zinc modified PPy coating, even after 96 h of exposure time to corrosive solution. 相似文献
999.
戴兴征 《有色金属(冶炼部分)》2004,(4):34-36
介绍锌精矿沸腾焙烧余热锅炉烟气性质,分析锅炉清灰方案设计思路,详细介绍了冲击波清灰的原理、安装及调试方法。根据两年多的生产实践,说明冲击波清灰完全满足生产工艺要求,而且具有免维护、运行费用省、操作简单等优点。 相似文献
1000.
目的 建立皮尔逊相关系数(Pearsoncorrelationcoefficient,PCC)和长短期记忆(longshortterm memory,LSTM)神经网络的反应液葡萄糖含量预测模型用以实时预测葡萄糖酸锌生产过程中反应液葡萄糖含量。方法 通过葡萄糖酸锌制备实验,结合PCC理论确定对反应液葡萄糖含量有较大影响的因素,对这些因素进行数据采集并将其作为神经网络的输入变量,采集反应液葡萄糖含量数据并进行处理,将其作为神经网络的输出变量,进而建立反向传播神经网络(backpropagation neural network, BP)和LSTM神经网络的反应液葡萄糖含量预测模型。结果 通过100次模型迭代训练,对照BP反应液葡萄糖含量预测模型可以看出LSTM反应液葡萄糖含量预测模型在测试集的误差约为0.45%,误差较小,准确度较高。结论 基于LSTM反应液葡萄糖含量预测模型显著提高了预测精度,相比现有检测方法更加智能高效,能够有效辅助生产进行。 相似文献