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81.
Highly Reactive Nonheme Iron(III) Iodosylarene Complexes in Alkane Hydroxylation and Sulfoxidation Reactions 下载免费PDF全文
Dr. Seungwoo Hong Dr. Bin Wang Dr. Mi Sook Seo Dr. Yong‐Min Lee Myoung Jin Kim Prof. Dr. Hyung Rok Kim Prof. Dr. Takashi Ogura Dr. Ricardo Garcia‐Serres Dr. Martin Clémancey Prof. Dr. Jean‐Marc Latour Prof. Dr. Wonwoo Nam 《Angewandte Chemie (International ed. in English)》2014,53(25):6388-6392
High‐spin iron(III) iodosylarene complexes bearing an N‐methylated cyclam ligand are synthesized and characterized using various spectroscopic methods. The nonheme high‐spin iron(III) iodosylarene intermediates are highly reactive oxidants capable of activating strong C? H bonds of alkanes; the reactivity of the iron(III) iodosylarene intermediates is much greater than that of the corresponding iron(IV) oxo complex. The electrophilic character of the iron(III) iodosylarene complexes is demonstrated in sulfoxidation reactions. 相似文献
82.
Mengwei Yuan Sofiene Abdellaoui Hui Chen Matthew J. Kummer Christian A. Malapit Chun You Shelley D. Minteer 《Angewandte Chemie (International ed. in English)》2020,59(23):8969-8973
Aliphatic synthetic intermediates with high added value are generally produced from alkane sources (e.g., petroleum) by inert carbon–hydrogen (C?H) bond activation using classical chemical methods (i.e. high temperature, rare metals). As an alternative approach for these reactions, alkane monooxygenase from Pseudomonas putida (alkB) is able to catalyze the difficult terminal oxyfunctionalization of alkanes selectively and under mild conditions. Herein, we report an electrosynthetic system using an alkB biocathode which produces alcohols, epoxides, and sulfoxides through bioelectrochemical hydroxylation, epoxidation, sulfoxidation, and demethylation. The capacity of the alkB binding pocket to protect internal functional groups is also demonstrated. By coupling our alkB biocathode with a hydrogenase bioanode and using H2 as a clean fuel source, we have developed and characterized a series of enzymatic fuel cells capable of oxyfunctionalization while simultaneously producing electricity. 相似文献
83.
Lichen Liu Miguel Lopez‐Haro Debora M. Meira Patricia Concepcion Jose J. Calvino Avelino Corma 《Angewandte Chemie (International ed. in English)》2020,59(36):15695-15702
Preparation of supported metal catalysts with uniform particle size and coordination environment is a challenging and important topic in materials chemistry and catalysis. In this work, we report the regioselective generation of single‐site Ir atoms and their evolution into stabilized subnanometric Ir clusters in MWW zeolite, which are located at the 10MR window connecting the two neighboring 12MR supercages. The size of the subnanometric Ir clusters can be controlled by the post‐synthesis treatments and maintain below 1 nm even after being reduced at 650 °C, which cannot be readily achieved with samples prepared by conventional impregnation methods. The high structure sensitivity, size‐dependence, of catalytic performance in the alkane hydrogenolysis reaction of Ir clusters in the subnanometric regime is evidenced. 相似文献
84.
Ni/HZSM-5催化剂的结构及其催化山梨醇水相加氢合成烷烃性能 总被引:1,自引:0,他引:1
采用浸渍法制备了Ni/HZSM-5双功能催化剂,考察了焙烧温度对催化剂结构及其催化山梨醇水相加氢合成C5~C6烷烃性能的影响.结果表明,在金属中心和酸性载体的协同作用下,通过山梨醇中C-O键加氢和异构化高选择性合成了C5~C6烷烃.经500°C焙烧的Ni/HZSM-5催化剂上山梨醇水相加氢的活性最高,山梨醇转化率为62.0%,戊烷和己烷的总选择性为76.4%,其中异己烷选择性达45.4%.对催化剂进行N2物理吸附、X射线衍射、NH3程序升温脱附和H2程序升温还原等表征后发现,经500°C焙烧催化剂的有效比表面积和孔体积均明显增大,HZSM-5负载的硝酸镍分解成较小晶粒的NiO,表面酸量适中,且Ni物种与载体相互作用较强,较易被H2还原,Ni还原度达100%.这是其催化活性最高的原因. 相似文献
85.
Prof. Hao Wang Dr. Xinglong Dong Jiayu Ding Kaifang Wang Liang Yu Shang Zhang Prof. Yu Han Dr. Qihan Gong Prof. An Ma Prof. Jing Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(46):11795-11798
The separation of alkanes, particularly monobranched and dibranched isomers, is of paramount importance in the petrochemical industry for optimizing the feedstock of ethylene production as well as for upgrading the octane number of gasoline. Here, we report the full separation of linear/monobranched alkanes from their dibranched isomers by a robust and easily scalable metal-organic framework material, Co3(HCOO)6. The compound completely excludes dibranched alkanes but adsorbs their linear and monobranched isomers, as evidenced by single-component and multicomponent adsorption measurements. More importantly, the material exhibits excellent performance in separating naphtha and is capable of providing high quality feedstock for the production of ethylene and gasoline components with high octane number, making it a promising candidate for naphtha separation in petrochemical industry. 相似文献
86.
《Molecular physics》2012,110(11-12):1383-1389
Solid–liquid equilibria for three binary mixtures, n-Eicosane (1)?+?Lauric acid (2), n-Tetracosane (1)?+?Stearic acid (2), and n-Octacosane (1)?+?Palmitic acid (2), were measured using a differential scanning calorimeter. Simple eutectic behaviour was observed for these systems. The experimental results were correlated by means of the modified UNIFAC (Larsen and Gmehling versions), UNIQUAC and ideal models. The root-mean-square deviations of the solubility temperatures for all measured data vary from 0.26 to 3.15?K and depend on the particular model used. The best solubility correlation was obtained with the UNIQUAC model. 相似文献
87.
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89.
用图示法和非线性规划的方法对直链烷烃同系物最高成键分子轨道能级、最低成键分子轨道能级,电离电位,氧化半波电位,正常沸点,正常熔点、临界压力、临界温度、密度、折光率、表面张力和粘度和12种结构型性质和凝聚型性质的变化规律进行研究,结果发现,直链烷烃结构型性质和凝聚型性质一般能遵守同系对数递变规律,各种结构型性能和凝聚型性能均与对数递变函数呈优良的相关性,相关系数均大于0.99,用同系对数递变规律对直 相似文献
90.
The crystallization kinetics and morphologies of dilute binary blends of the monodisperse alkane n‐C122H246 in n‐C246H494 and vice versa have been investigated. With a molecular length ratio close to two, this pair of n‐alkanes does not produce permanent cilia when once‐folded C246H494 molecules cocrystallize with extended chains of C122H246. In this condition, the supplementary splaying of adjacent dominant lamellae and the consequently more spherulitic textures, which are present in previous blends for which a longer guest molecule gives permanent cilia, are absent, although other features of blend crystallization remain. Specifically, the isothermal radial growth rate is constant for cocrystallizing blends, although less than for their pure hosts, but becomes nonlinear with cellulation when C122H246 forms a segregated population within extended‐chain C246H494. Increased nucleation in the blends give smaller scale textures than for the host materials, but the presence of a second component reduces splaying and thereby disfavors spherulitic growth. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 2874–2887, 2001 相似文献