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排序方式: 共有661条查询结果,搜索用时 15 毫秒
1.
Caio Machado Fernandes Marcos Vinícius Palmeira de Mello Nazir Escarpini dos Santos Alessandra Mendonça Teles de Souza Mauricio Lanznaster Eduardo Ariel Ponzio 《工业材料与腐蚀》2020,71(2):280-291
4-Chloro-N-(pyridin-2-ylmethyl)aniline (CPYA) was synthesized by a simple and inexpensive method and tested as a corrosion inhibitor in acid medium for mild steel by using gravimetric studies and electrochemical measurements. An average maximum efficiency of 96.0% was achieved at 4.59 mmol/L. Corrosion kinetic and thermodynamic parameters were also analyzed. Surface analyses (atomic force microscopy and scanning electron microscopy) show that protection is enabled by adsorption on the metal, forming a film. Quantum chemical calculations were performed to access information regarding the molecular structure in the corrosive medium and to support interpretation of the results obtained by experimental methods. 相似文献
2.
将来瓦希尔骨架材料MIL-53(Al)引入到聚醚共聚酰胺(PEBA-2533)高分子相中制备了不同填充量的PEBA/MIL-53(Al)杂化膜并用于渗透汽化分离水中微量苯胺。X-射线衍射结果证实MIL-53(Al)被成功合成。扫描电镜和激光粒度分析结果表明所制备MIL-53(Al)颗粒粒径在纳米尺度范围内。采用扫描电镜、红外光谱、X-射线衍射、差示扫描量热和水接触角对杂化膜进行了表征,并考察了杂化膜的溶胀行为和分离性能。结果表明,所得杂化膜的热稳定性较好。当MIL-53(Al)质量分数小于20%时,MIL-53(Al)在高分子相中分散均匀,继续增大填充量出现团聚现象。杂化膜的结晶度随MIL-53(Al)填充量的增加而降低。MIL-53(Al)的引入增强了杂化膜的疏水性和溶胀度。在料液温度为60℃、膜下游压力400Pa、料液苯胺质量分数为3.6%时,MIL-53(Al)质量分数为20%的杂化膜(M-20)综合分离性能最优,渗透通量达到2.15kg/(m2·h),分离因子为264。12天的稳定性测试结果表明所得杂化膜分离性能无显著变化,能够满足渗透汽化应用要求。 相似文献
3.
研究了Fe(Ⅱ)/亚硫酸盐体系活化溶解氧氧化降解苯胺的工艺并探索了氧化过程中的主要活性物种。结果表明,溶解氧是苯胺氧化的氧化剂,pH=4.0以及亚硫酸盐与Fe(Ⅱ)物质的量之比为10:1的体系对苯胺的催化效果最佳,苯胺去除率可达70%。Fe(Ⅱ)在体系中发挥着重要作用,只存在亚硫酸盐的情况下,苯胺去除效果下降至30%以下,且反应时间由90 min延长至40 h。在Fe(Ⅱ)/亚硫酸盐体系中,pH=3.0条件下Fe(Ⅱ)全部被氧化成Fe(Ⅲ),而在其它pH值条件下,Fe(Ⅱ)与Fe(Ⅲ)主要以络合物形式存在。叔丁醇与甲醇的自由基掩蔽实验进一步证实了SO4·-是氧化过程中的主要氧化物种,而SO5·-是次要氧化物种。实验结果丰富了Fe(Ⅱ)/亚硫酸盐体系催化溶解氧降解有机污染物的研究,表明其在有机工业废水处理方面具有很好的应用前景。 相似文献
4.
《International Journal of Hydrogen Energy》2019,44(10):4698-4706
Polyaniline is a typical conducting polymer with high migration electron rate, good stability, eco-friendly properties, and high absorption coefficients for visible light. In the present study, polyaniline decorated Pt@TiO2 for visible light-driven H2 generation is reported for the first time. The above-mentioned nanocomposite is prepared through a simple oxidative-polymerization and characterized by infrared spectroscopy, transmission electron microscopy, X–ray diffraction, thermogravimetric analysis, and ultraviolet–visible diffuse reflectance spectra. Polyaniline modification improves the absorption of the nanocomposite in visible light region via a photosensitization effect similar to dye–sensitization but does not influence the crystal structure and size of Pt@TiO2. The polyaniline modified Pt@TiO2 exhibits a remarkable visible light activity (61.8 μmol h−1 g−1) and good stability for H2 generation (with an average apparent quantum yield of 10.1%) with thioglycolic acid as an electron donor. This work provides new insights into using conducting polymers, including polyaniline, as a sensitizer to modify Pt@TiO2 for visible-light hydrogen generation. 相似文献
5.
6.
建立了气相色谱法对苯胺及其五种衍生物进行分离与同时测定的方法。最佳色谱分离条件如下:HP-5MS空心毛细管柱(30 m×0.32 mm×0.25μm);程序升温方式:初始温度70℃,以20℃/min升至150℃,保持1 min;以氮气为载气,流速为5.0 m L/min;尾吹气(氮气)流速为30 m L/min;氢气流速为35 m L/min;空气流速为400 m L/min;不分流进样,进样量为1μL;进样口温度为260℃,检测器温度为320℃。在最佳实验条件下,六种组分在4 min内全部出峰,达到较好的分离,实现对组分的分离与同时检测。 相似文献
7.
以苯胺类衍生物为起始原料,先经Sandmeyer合成得到靛红类衍生物,再经水合肼还原得到系列吲哚-2-酮类衍生物:7-氯吲哚-2-酮、5-氯吲哚-2-酮、5-甲基吲哚-2-酮和5-溴吲哚-2-酮,产率分别为52.1%、49.8%、59.3%和65.2%。 相似文献
8.
M. Bayat 《Petroleum Science and Technology》2017,35(16):1635-1641
Auto-thermal heat exchanger configurations are recognized as a novel concept in process intensification. In the current study, the influence of operating conditions in a novel coupling reactor with radial-flow pattern is investigated for heavy paraffin dehydrogenation process. Catalytic hydrogenation of nitrobenzene to aniline takes place in the exothermic side and supplies the necessary heat for the endothermic dehydrogenation of heavy paraffin reaction. The performance of the reactor is numerically investigated for various key operating variables, such as inlet molar flow rates of exothermic and endothermic streams, number of subsections, and exothermic side angle. The reactor performance is analyzed based on temperature, olefin production rate, and nitrobenzene conversion. 相似文献
9.
N-甲基苯胺(NMA)广泛应用于化工生产中,以苯胺和甲醇为原料,采用气相法合成NMA,研究的重点在于提高CuO/ZnO/Al_2O_3催化剂的稳定性。通过分析CuO/ZnO/Al_2O_3催化剂的制备条件及助剂的作用,为合成优良催化性能的催化剂提供理论指导。 相似文献
10.
Self‐assembled centimetre‐sized rods obtained in the oxidation of o‐phenylenediamine and aniline 下载免费PDF全文
Venkata Sai Sriram Mosali Graham A Bowmaker Melvin Gerard Paul A Kilmartin Jadranka Travas‐Sejdic Zoran D Zujovic 《Polymer International》2015,64(9):1135-1141
Morphologically well‐defined rods of approximately 1 cm in length are effectively and economically obtained by mixing ortho‐phenylenediamine (30 mmol L?1) with ammonium persulfate (12.5 mmol L?1) in an acidic solution (0.37 mol L?1 HCl) at room temperature with and without the presence of 50 mmol L?1 aniline. These self‐assembled, morphologically uniform products can be potentially scaled up and used as morphological templates to fabricate well‐defined structures of other materials such as conducting polymers. The products were characterized using Raman, UV‐visible, high‐resolution NMR (1H and 13C) and mass spectroscopies, X‐ray diffraction, scanning electron microscopy and elemental analysis. Apart from certain differences in visual appearance and in X‐ray diffractograms, other analytical data suggest that there are no structural changes upon addition of aniline into the reaction mixture. NMR and mass spectra imply that all syntheses carried out either with or without aniline result in a mixture of two products, attributed to 2,3‐phenazinediamine and 3‐aminophenazin‐2‐ol. A formation mechanism based on hydrogen bonding and π–π stacking has been proposed. © 2015 Society of Chemical Industry 相似文献