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61.
海上漏油的频繁发生以及采油废水、工业含油污水的大量排放造成水资源大片污染和生态系统平衡的严重破坏。目前,从水体中分离油品和有机污染物已受到越来越多的商业和学术的关注。石墨烯基气凝胶是由二维石墨烯片层组装成的三维宏观材料,因其孔隙率高、比表面积大、密度低、机械性能强等特点在油水分离领域具有广阔的应用前景,已成为当今的研究热点之一。本文结合最新研究进展系统地总结了石墨烯基气凝胶的结构设计、组装及干燥方法,归纳了近年来其在油水分离中的应用进展,并对石墨烯基气凝胶在油水分离领域的研究现状和未来研究方向做了简要评述,以期为该领域的深入探索提供新的视角。 相似文献
62.
离子交换法处理含Cr(Ⅵ)废水的研究 总被引:4,自引:2,他引:4
采用201×7强碱性阴离子交换树脂处理模拟含Cr(Ⅵ)废水,探讨了废水酸度、交换时间、浓度对Cr(Ⅵ)去除率的影响以及树脂再生所需的合适温度和再生剂浓度。结果表明,201×7强碱性阴离子交换树脂处理模拟含Cr(Ⅵ)废水,具有交换容量大、交换效果好、树脂再生条件较简单等优点。并对实际含铬废水进行了处理,废水中Cr(Ⅵ)的初始浓度为1 540 mg/L,处理量达52 BV(床体积)时,出水中Cr(Ⅵ)的浓度仍小于0.5 mg/L,达到国家排放标准。树脂交换容量约80 mg/g。用8%NaOH溶液,在50℃条件下进行再生效果较好,再生率大于95%,可实现树脂的重复使用。 相似文献
63.
Zhen-Xue Liu Jung-Nam Park S. H. R. Abdi Seung-Kyu Park Yong-Ki Park Chul Wee Lee 《Topics in Catalysis》2006,39(3-4):221-226
In this paper, the ethylene adsorption capacities of the nano-sized carbon hollow spheres (CNB) and active carbon (AC), the
Pd (PdCl2) impregnated CNB or AC (Pd/CNB, Pd/AC) and heat treatment under various conditions, were studied at different ethylene concentrations
from 64 to 1060 ppm. The results indicated that AC had a good ethylene adsorption capacity at high ethylene concentration.
Pd impregnation decreased the ethylene adsorption capacity of AC. Heat treatment and H2 activation could increase the ethylene adsorption capacity, but also lowered than AC itself. CNB had lower ethylene adsorption
capacity than AC, but heat treatment and H2 activation could increase its ethylene adsorption capacity markedly. With activating condition from heat treatment in N2 at 300 °C to activation in H2/N2 at 100 °C, to activation in H2 at 200 °C, and to activation in H2 at 300 °C, the ethylene adsorption capacity of Pd/CNB was increased regularly. At low ethylene concentration, viz., 64 ppm,
the ethylene adsorption quantities (q
a) by Pd/CNB activated in H2 at 200 or 300 °C were higher than any other adsorbents. So, activated in H2 atmosphere at higher than 100 °C, Pd/CNB is particularly advantaged for adsorbing low concentration of ethylene. Amongst
all the adsorbents used, Pd/CNB activated in H2 atmosphere at 300 °C for 2 h has the highest ethylene adsorption capacity at lower concentration than 125 ppm. In addition,
all the CNB, Pd/CNB, AC, and Pd/AC samples can be easily regenerated in airflow for more than 3 h. 相似文献
64.
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67.
废橡胶再生技术研究进展 总被引:12,自引:0,他引:12
综述了废橡胶再生利用的技术和方法,介绍了废橡胶的物理再生、化学再生的再行剂和微生物再生方法及进展,并对化学再生助剂、植物再生剂和生物再生助剂的再生效果进行了系统评述。 相似文献
68.
阐述了离子膜法烧碱系统中螯合树脂塔的工艺设计和生产中已出现和可能出现的问题,并介绍了解决问题的方法。 相似文献
69.
ABSTRACT This study explores an electrochemical adsorption method on the regeneration of aqueous drilling fluid waste. Response surface analysis was applied to investigating the electrochemical factors on the adsorption performance. The response surface polynomial model optimized the preferred electrochemical adsorption conditions with adsorption time of 20 min, spacing electrodes of 5 cm, adsorption concentration of 5% and NaCl concentration of 2 g/L. The model calculated electrochemical adsorption amount of drilling fluid showed only 1.3% deviation from the experimental results. Thus, the model could provide effective support for the device design and application of drilling fluid electrochemical adsorption process. 相似文献
70.
In this study, we explored a new ion exchange material synthesized by radical polymerization of styrene and 2‐acrylamido‐2‐methyl‐1‐propane sulfonic acid by using 2,2′‐azo‐isobutyronitrile (1 mol %) and divinylbenzene (0.5 mol %) as initiator and crosslinking reagents, respectively. The resin was obtained from a large excess (90%) of styrene in the feed. The yield was 72.3%. The resin was completely insoluble in water and characterized by elemental analysis, FTIR spectroscopy, scanning electron microscopy, and thermal analysis. The metal ion retention capability was investigated for Ag(I), Hg(II), Cd(II), Zn(II), Pb(II), and Cr(III). The effect of pH, time, and resin/metal ion mol ratio on the metal ion retention was studied. Selectivity of the resins from a mixture of metal ions and the maximum retention capacity at optimum pH were also determined. The recovery of the resin by using 1 and 4 M HClO4 and HNO3 demonstrated that it is possible to recover the resin above 80%. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1230–1235, 2003 相似文献