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吸附脱硫技术具有操作条件温和、节能、不改变燃油品质和成本低等特点而备受关注。针对噻吩类难脱除硫化物的深度脱除和转化问题,综述了近年来应用多孔吸附材料选择性吸附超深度脱除燃油中噻吩类硫化物的作用机理及最新研究进展。重点分析了分子筛、金属有机骨架、多孔炭材料、复合材料等不同吸附剂的研究现状,并探讨了各种吸附材料的吸附机理、改性方式和优缺点。本文指出分子筛因优异的热稳定性、高比表面积、均一的孔道结构、低成本和易于工业化等特点,是目前最具优势的吸附剂材料。未来研究应着重阐明吸附机理、提高合成便捷性、脱硫性能以及再生能力,更全面系统的研究将为开发具有理想选择性和再生能力的高效吸附剂奠定基础。 相似文献
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在B3LPY/6-311+G**水平上计算了噻吩与NH3、H2O和HF形成的复合物的结构、能量及氢键关键点处电荷密度拓扑性质。结果表明,噻吩与NH3形成两种弱C-H…N氢键;N被O取代后,除C-H…O氢键外,形成更稳定的O-H…π结构;F取代O时形成强度更大的F-H…S和F-H…π氢键,这表明典型的氢键在电负性较小的分子复合物中较为普遍;在电负性较大的分子复合物中,小分子更倾向于从噻吩平面上方接近噻吩,形成其他类型的氢键和X-H…π氢键。氢键关键点处的电荷密度拓扑性质结果表明,这些氢键强度较弱,为闭壳层相互作用。本文结论为噻吩类超分子功能材料体系的设计和合成提供一定的指导。 相似文献
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Recent progress in derivatized polythiophenes (PTs) and polymerized thiophene derivatives is reviewed, with emphasis on applications that involve devising and fabricating selective and sensitive chemo- and biosensors. The literature results summarized show that appreciable selectivity is attained if derivatized polythiophene films are used as recognition units. Illustrative examples include determination of polyatomic anions and metal cations, volatile organic compounds, and biocompounds including glucose and nucleic acids. Moreover, progress is presented in the use of derivatized thiophenes as functional monomers for preparation of molecularly imprinted polymers (MIPs) for chemosensing. Thanks to the range of synthetic procedures developed for preparation of derivatized PTs, these electronically conducting polymers have served as excellent recognition units for fabricating highly sensitive and selective chemosensors for target analytes. 相似文献
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A novel N-coumarin derivative, namely 9,10-[di-p-(7-diethylamino-coumarin-3-yl) thiopheneyl]anthracene ((CTh)2A), containing anthracene as the core and 3-thiophene N-coumarin as the substituent was synthesized, and its structure was confirmed by 1H NMR and IR spectroscopies. The optical, electrochemical and thermal properties were investigated. Thermogravimetric analysis and PL spectra reveal the high thermal and good photoluminescence characteristics. The coumarin derivative exhibits blue photoluminescence with high fluorescence quantum yield in solution (up to 40%). The results show that the derivative would serve as promising organic light-emitting diode luminescent material. 相似文献
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利用固定化细胞技术提高热带假丝酵母降解高浓度噻吩的效率,考察了固定化包埋的载体类型及固定化的方法,优化了固定化微球降解噻吩的实验条件。实验结果表明:用2%的海藻酸钠固定化热带假丝酵母,微球表面可形成一层致密的薄膜,将大量细胞包埋在微球里,菌体密度达到5×1010 CFU/g微球;噻吩降解实验中较佳条件为:微球接种量7 g/100 mL、培养基初始pH 8.5~9.0、培养温度30℃。在500 mg/L噻吩的培养液中,培养16 h时降解可达62.3%。 相似文献
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Benzoselenadiazole, quinoxaline and thieno[3,2-b]thiophene are the units preferred in conducting polymers due to their electrochemical properties. There are no reports in the literature on polymers containing both moieties. In this study, novel benzoselenadiazole, quinoxaline and thieno[3,2-b]thiophene based monomers; 4-(3a,6a-dihydrothieno[3,2-b]thiophen-2-yl)-7-(thieno[3,2-b]thiophenyl)benzo[c][1,2,5]selenadiazole (BSeTT) and 2,3-bis(3,4-bis(decyloxy)phenyl)-5,8-dibromo-2,3-dihydroquinoxaline (QTT) were synthesized via Stille Coupling and polymerized electrochemically. These polymers were characterized in terms of their spectroelectrochemical and electrochemical properties by cyclic voltammetry and UV–Vis–NIR spectroscopy. Spectroelectrochemistry analysis of PBSeTT revealed an electronic transition at 525 nm corresponding to π–π* transition with a band gap of 0.93 eV whereas PQTT revealed electronic transitions at 440 and 600 nm corresponding to π–π* transitions with a band gap of 1.30 eV. Electrochromic investigations showed that PBSeTT has gray color PQTT switching between green and gray. Switching time of the polymers was evaluated by a kinetic study upon measuring the percent transmittance (%T) at the maximum contrast point. 相似文献
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Phase equilibria and structural properties of thiophene/[Bmim][BF4]: A molecular insight from monte carlo simulations 下载免费PDF全文
Yongping Zeng Chunfeng Wang Junmei Hu WenLin Xu Yueyang Xu Shengui Ju 《American Institute of Chemical Engineers》2014,60(11):3916-3924
The phase equilibria of thiophene in 1‐butyl‐3‐methylimidazolium tetrafluoroborate ([Bmim][BF4]) is calculated by Monte Carlo simulation in Gibbs ensemble using a united atom force field. The liquid density of studied ionic liquid and the vapor pressure of thiophene in [Bmim][BF4] were compared with corresponding experimental data reported in the literature, and a good agreement was obtained. In order to describe the solubility of thiophene in this ionic liquid, we have calculated the radial distribution functions and spatial distribution functions of thiophene/IL mixtures to study the interaction of thiophene with cations and anions of [Bmim][BF4] in the liquid phase. The local composition concept in fluid was also examined to give further insight into the liquid structure. The results show that thiophene is well organized around the terminal carbon atom of the butyl or methyl chain attached to the imidazolium ring of cations and tends to adopt a symmetrically distribution on the anions. © 2014 American Institute of Chemical Engineers AIChE J, 60: 3916–3924, 2014 相似文献
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