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101.
分析了东濮凹陷东南部的油气地球化学特征,以濮深10井为例,计算了砂泥岩剖面的孔隙度和流体压力,以及不同性质生油岩在演化阶段的油气生成量。用生油岩孔隙中油气饱和度控制油气排出量的方法,可得到油气初次运移量和运移时期。研究表明,有机质丰度高、类型好的生油岩,在进入生油门限时期不久就有油气排出;而有机质丰度低的生油岩几乎无液态油排出,只会在高、过成熟条件下排出天然气。 相似文献
102.
Tao Wang Yi-Fu Kong Yang Xu Jian Fan Hua-Jian Xu Donald Bierer Jun Wang Jing Shi Yi-Ming Li 《Tetrahedron letters》2017,58(42):3970-3973
Solid-phase incorporation of pre-prepared diaminodiacids has been established as an efficient strategy for the chemical synthesis of peptide disulfide bond mimics. Hydrocarbon-bridged diaminodiacids represent one important category of diaminodiacids but they remain difficult to synthesize. In the present work, we reported the use of newly-developed nickel catalyzed reductive cross-coupling reaction to efficiently synthesize diaminodiacids with hydrocarbon bridges. Through optimization of the reaction conditions, the yield of the hydrocarbon bridge formation reached about 50%, even when the reaction was scaled up to the gram level. Subsequently, using our recently developed Dmab/ivDde protecting group system, we obtained a new hydrocarbon-bridged diaminodiacid that are suitable for metal-free deprotection conditions. We demonstrated the utility of this Dmab/ivDde protected hydrocarbon-bridged diaminodiacid in the synthesis of a disulfide surrogate of oxytocin. 相似文献
103.
通过对毛管压力曲线的双曲线拟合,从压汞毛管压力资料中提取一个储层孔隙结构方面新的重要参数RA,其物理意义是汞在岩石中开始形成一个连续且内部连通良好的孔隙系统时的孔喉半径。并通过实例用RA顶点的大小评价储层的好坏及油气聚集部位,效果十分理想。 相似文献
104.
东部凹陷荣兴屯构造特征及油气远景 总被引:2,自引:2,他引:0
为了揭示荣兴屯构造带各局部构造的构造特征并优选出有利区带,通过构造平面图、剖面图以及平衡剖面图,对荣兴屯构造带的基本构造格局、次级构造单元、构造层划分、构造样式以及圈闭类型等进行了深入研究,阐明了其总体具有东西倾向分带、南北走向分段和垂向构造分层的变形特点,东西分为5个构造单元,上下分为4个构造层,中—南段较北段构造样式更为复杂,圈闭类型主要是断块、断鼻等构造型圈闭,各局部构造与不同构造层油气富集程度差别大。结合烃源发育与已探明油气藏分布特点,指出烃源岩、构造格局和断裂体系是控制油气成藏的主要因素,综合分析认为荣兴屯斜坡带是进一步勘探的有利区带,并对其油气成藏条件进行了扼要分析。 相似文献
105.
低碳烯烃(乙烯、丙烯等)是重要的基本有机原料, 一般通过蒸汽裂解或催化裂解生成得到.基于中国的资源结构特点, 发展非石油资源路线合成低碳烯烃具有重要的战略意义. 其中从煤、天然气等资源出发, 通过甲醇合成低碳烯烃就提供了这样一条可替代的路线. 因此分子筛催化甲醇制烯烃(MTO)反应在过去几十年获得了广泛的关注和研究. 为了获得高的产物选择性, 一般要求MTO分子筛催化材料具有较小的孔道结构以及合适的笼结构, H-SAPO-34和H-SAPO-18分子筛就具有这样的空间结构特点. 但是MTO催化反应产物分布多样复杂, 因此需要深入认识MTO催化反应机理, 从而优化设计分子筛结构和反应条件.目前已经形成的共识认为, MTO催化反应沿着烃池反应机理进行, 但是烃池活性中心的结构还存在很多争议. 我们曾系统研究了H-SAPO-18分子筛中多甲基苯的分布, 以及催化MTO反应的芳烃循环路线, 指出多甲基苯路线的总吉布斯自由能垒高于200 kJ/mol (673 K). 本文以四甲基乙烯(TME)作为代表性的烯烃烃池活性中心, 系统研究了H-SAPO-18分子筛催化MTO反应的烯烃循环路线. TME循环路线的总吉布斯自由能垒不大于150 kJ/mol, 远小于芳烃循环的总能垒. 因此, 烯烃本身有很大可能是H-SAPO-18催化MTO反应的烃池活性中心. 我们也指出了芳烃循环和烯烃循环路线的相似性, 这包括基元反应的相似性和中间体结构的相似性. 或者可以说, 芳烃循环和烯烃循环路线机理上没有区别, 关键是为了得到具有烷基(侧)链的裂解前驱体, 最后通过裂解生成低碳烯烃. 在烯烃循环路线中, 产物选择性与裂解前驱体(高碳烯烃、碳正离子等)的分布以及裂解动力学有关. 计算发现生成乙烯和丙烯的裂解基元反应能垒与裂解前驱体的碳数之间存在线性关系. 本文进一步强调了分子筛催化MTO反应中烯烃活性中心的重要性, 并且清楚指出了烯烃循环和芳烃循环的机理相似性. 相似文献
106.
Tapan K. Si Santu Chakraborty Alok K. Mukherjee Michael G.B. Drew Ramgopal Bhattacharyya 《Polyhedron》2008
Two oxovanadium(V) salicylhydroximate complexes, [VO(SHA)(H2O)] · 1.58H2O (1) and [V3O3(CSHA)3(H2O)3] · 3CH3COCH3 (2) have been synthesized by reaction of VO43− with N-salicyl hydroxamic acid (SHAH3) and N-(5-chlorosalicyl) hydroxamic acid (CSHAH3), respectively, in methanol medium. Compound 1 on reaction with pyridine 2,6-dicarboxylic acid (PyDCH2) yields mononuclear complex [VO(SHAH2)(PyDC)] (3). Treatment of compound 3 with hydrogen peroxide at low pH (2-3) and low temperature (0–5 °C) yields a stable oxoperoxovanadium(V) complex H[VO(O2)(PyDC)(H2O)] · 2.5H2O (4). All four complexes (1–4) have been characterized by spectroscopic (IR, UV–Vis, 51V NMR) and single crystal X-ray analyses. Intermolecular hydrogen bonds link complex 1 into hexanuclear clusters consisting of six {VNO5} octahedra surrounded by twelve {VNO5} octahedra to form an annular ring. While the molecular packing in 2 generates a two-dimensional framework hydrogen bonds involving the solvent acetone molecules, the mononuclear complexes 3 and 4 exhibit three-dimensional supramolecular architecture. The compounds 1 and 2 behave as good catalysts for oxygenation of benzylic, aromatic, carbocyclic and aliphatic hydrocarbons to their corresponding hydroxylated and oxygenated products using H2O2 as terminal oxidant; the process affords very good yield and turnover number. The catalysis work shows that cyclohexane is a very easily oxidizable substrate giving the highest turnover number (TON) while n-hexane and n-heptane show limited yield, longer time involvement and lesser TON than other hydrocarbons. 相似文献
107.
Adsorptive micellar flocculation (AMF) is a surfactant-based separation process based on the flocculation of micelles of
suitable anionic surfactants by Al3+. The micelles form large amorphous flocs which can be removed by filtration, which is attractive because soluble pollutants
are captured by the floc, thus providing a simple separation method. As the primary aim of AMF is the removal of anionic pollutants
from aqueous streams, it is important to investigate the influence of the various substances which may affect it. This article
discusses the influence of the presence of insoluble hydrocarbons on the flocculation of micelles of the anionic surfactant
dodecyl sulfate by Al3+. The ratio between surfactant remaining in solution and total surfactant and the ratio between Al3+ and surfactant in the flocculate are determined in systems composed of an aqueous solution containing a constant dodecyl
sulfate concentration of 0.05 M and a variable Al3+ concentration and an organic phase (decane) with phase volume ratios of decane/water ranging from 0 (no decane) to 0.15.
The flocculation is only slightly affected by the presence of decane for decane/solution ratios below 0.05, while the effect
(lower flocculated fraction) is more marked above this ratio.
Received: 25 October 1999/Accepted: 7 February 2000 相似文献
108.
109.
Modern scanning transmission electron microscopy (STEM) enables imaging and microanalysis at very high magnification. In the case of aberration-corrected STEM, atomic resolution is readily achieved. However, the electron fluxes used may be up to three orders of magnitude greater than those typically employed in conventional STEM. Since specimen contamination often increases with electron flux, specimen cleanliness is a critical factor in obtaining meaningful data when carrying out high magnification STEM. A range of different specimen cleaning methods have been applied to a variety of specimen types. The contamination rate has been measured quantitatively to assess the effectiveness of cleaning. The methods studied include: baking, cooling, plasma cleaning, beam showering and UV/ozone exposure. Of the methods tested, beam showering is rapid, experimentally convenient and very effective on a wide range of specimens. Oxidative plasma cleaning is also very effective and can be applied to specimens on carbon support films, albeit with some care. For electron beam-sensitive materials, cooling may be the method of choice. In most cases, preliminary removal of the bulk of the contamination by methods such as baking or plasma cleaning, followed by beam showering, where necessary, can result in a contamination-free specimen suitable for extended atomic scale imaging and analysis. 相似文献
110.
The effect of low-frequency high-power ultrasound on hydrocarbon-based ionomers, cation exchange sulfonated phenylated polyphenylene (sPPB-H+) and anion exchange hexamethyl-p-terphenyl poly(benzimidazolium) (HMT-PMBI), was studied. Ionomer solutions were subjected to ultrasonication at fixed ultrasonic frequencies (f = 26 and 42 kHz) and acoustic power (Pacous = 2.1 – 10.6 W) in a laboratory-grade ultrasonication bath, and a probe ultrasonicator; both commonly employed in catalyst ink preparation in research laboratory scale. Power ultrasound reduced the polymer solution viscosity of both hydrocarbon-based ionomers. The molecular weight of sPPB-H+ decreased with irradiation time. Changes in viscosity and molecular weight were exacerbated when ultrasonicated in an ice bath; but reduced when the solutions contained carbon black, as typically used in Pt/C-based catalyst inks. Spectroscopic analyses revealed no measurable changes in polymer structure upon ultrasonication, except for very high doses, where evidence for free-radical induced degradation was observed. Ionomers subjected to ultrasound were used to prepare catalyst layers and membrane electrode assemblies (MEA)s. Despite the changes in the ionomer described above, no significant differences in electrochemical performance were found between MEAs prepared with ionomers pre-subjected to ultrasound and those that were not, suggesting that fuel cell performance is tolerant to ionomers subjected to ultrasound. 相似文献