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41.
平整废液是带钢冷精轧过程中产生的一种废液,是一种较难处理的高浓度有机废水,其生化性较差,传统的生物处理难以奏效,对于此类废水,国内外尚无成熟的处理工艺。采用芬顿(Fenton)氧化工艺对某公司生产的平整液进行了试验研究,研究了初始pH值、硫酸亚铁投加量、H2O2投加量以及混凝pH值等因素对COD去除效果的影响。通过试验研究,确定了反应温度、初始pH值、FeSO4和H2O2投加量等最佳处理工艺条件。在最佳处理条件下,COD去除率可达56%,同时BOD5/COD由0.17提高到0.48,废水的可生化性得到明显改善,可以满足后续生化处理的进水要求。 相似文献
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阐述了润滑油真空分离与聚结分离脱水的工作原理及试验方法,选取L-TSA46汽轮机油作为试验对象,在相同条件下进行了对比试验,结果表明:当含水量高于约2×10-4采用聚结分离比采用真空分离效率高、能耗低;当含水量低于约2×10-4采用真空分离比采用聚结分离效率高、能耗低;当含水量低于6×10-5则只能采用真空分离。 相似文献
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Wen-Tien Tsai 《Energy》2011,36(7):4333-4339
Utilizing used lubricants as energy sources has been currently demonstrated to be one of the best available waste management methods. In this regard, used lubricants for use as energy sources in Taiwan thus became popular in recent years. The objective of this study was to present a comprehensive analysis of used lubricant-to-energy in Taiwan, which includes status of lubricant consumption, and used lubricant generation and its recycling (i.e., collection & treatment) management system. It was found that a major market for utilizing used lubricants in Taiwan (over 90%) was reused as fuel oils or auxiliary fuels in the cogeneration system. Under the regulatory authorization of the Waste Management Act and the Petroleum Administration Act, the central competent authorities encouraged the energy-intensive industries in the waste-to-energy through the excess electricity purchase and subsidiary incentives. Based on the certified volume of collected used lubricant and its energy use proportion in 2009, the total energy potential and the environmental benefit of mitigating CO2 emissions in place of fuel oils were preliminarily calculated to be around 9.4 × 102 TJ and 7.3 × 107 kg, respectively. 相似文献
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AbstractWhite etching cracking (WEC) is a subsurface bearing failure mechanism influenced by a number of factors, including lubricant composition. Certain metal-containing lubricants have been reported to promote WEC-induced failure; however, the exact mechanisms linking lubricant effects on WEC propensity are still not fully understood. An interesting field that has not been elucidated is the influence of additive concentration and tribofilm growth on WEC initiation, propagation, and failure. The investigations conducted in this work involved two series of oil formulations: one with additives that give rise to WEC (WEC oils) in different combinations and concentrations and another with additives that do not cause WEC (non-WEC oils). A mini traction machine (MTM) in combination with a spacer layer imaging machine (SLIM) was employed to study the growth of tribofilms and their influence on friction response. Insights from the MTM-SLIM study allowed for better interpretation of FE8 bearing tests. When using oils that contribute to WEC formation, the tribofilm-induced WEC mechanism was confirmed, with cracks initiating as early as after 20 h of FE8 testing. Metal-containing additives were found to favor the formation of WECs by generating a high-friction tribofilm and increasing the water content in the lubricant. Furthermore, the source of subsurface H associated with WEC failure is investigated using heavy water (D2O)-saturated oil. A mechanism of water dissociation induced in tribofilm growth (incubation period) is proposed in this article. 相似文献
48.
四辊冷轧机第三倍频程颤振 总被引:5,自引:1,他引:4
四辊冷轧机有时会出现一种不稳定的高频自激振动,严重妨碍生产及安全。它既与轧制工艺相关,又与振动理论有联系,必须将二者结合起来进行研究,才能解决问题。 相似文献
49.
车用发动机磨合油研究 总被引:2,自引:0,他引:2
超精细金刚石(UDD)粉是利用爆炸法人工合成的具有使用价值的纳米材料,它具有一系列特殊的物理及化学特性,针对车用内燃机磨合特点,并利用UDD的特殊性能,研制一种高效专用内燃机磨合油。 相似文献
50.
S.D. Supekar A.F. Clarens D.A. Stephenson S.J. Skerlos 《Journal of Materials Processing Technology》2012,212(12):2652-2658
This paper investigates the cooling and lubrication properties of supercritical carbon dioxide (scCO2) sprays as potential substitutes for aqueous emulsions and straight oils used in the metalworking industry today. Sprays of rapidly expanding scCO2 act to cool and lubricate machining and forming processes by delivering a mixture of dry ice and lubricant deep into the cutting/forming zone. In this work, experiments with turning, milling, drilling, thread cutting, and thread forming were performed with scCO2 and other metalworking fluids (MWFs) to evaluate their relative performance with respect to tool wear and machining torque. Observations reveal that scCO2–MWFs are more effective in removing heat from the tool-workpiece interface than conventionally delivered (flood) aqueous MWFs as well as other gas-based MWF sprays. In addition, scCO2–MWFs delivered in lubricant-expanded phase, where scCO2 is used to increase volume of lubricant in the spray field, are shown to provide better lubricity than straight oils and oil-in-air minimum quantity lubrication (MQL) sprays. As a result, scCO2–MWFs can reduce tool wear and improve machining productivity in a wide range of manufacturing operations leading to appreciable improvements in the economics of manufacturing. Also given that CO2 is a recovered waste gas that is non-toxic, scCO2–MWFs can improve the environmental and worker health performance of manufacturing operations. 相似文献