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991.
本文报道了由新型杂环苯并碲唑衍生的4个染料中间体以及三种类型共6个部花青。染料合成的条件依酸性酮亚甲基核而异。研究了染料吸收光谱的溶剂效应, 发现极性较弱的罗丹宁部花青随着溶剂极性增大呈现吸收峰的显著红移, 而极性较强的双甲酮及巴比妥酸部花青的吸收则显示一定程度的蓝移。利用共振理论解释了上述现象。同时发现具有相似溶剂效应的两种部花青的转移能量(E~T)图呈现很好的线性关系, 有可能用作溶剂极性的指示剂。  相似文献   
992.
Adsorption and diffusion of tri-sulfonated azo dyes, C.I. Acid Red 18 and C.I. Acid Red 27 onto waterswollen cellulose membrane has been studied at 25°C. Affinities of these dyes onto cellulose were evaluated by the coefficients of Freundlich equation. Diffusion behavior of these days was analyzed on the basis of a parallel transport theory by surface and pore diffusion. The results could be described by the parallel diffusion model provided that adsorption was stimulated by addition of NaCl. The surface diffusivities for the parallel diffusion model were correlated by the affinity of the dyes, on the other hand, the pore diffusivities for the model were affected by aggregation of the dye depending on its structure and NaCl concentration.  相似文献   
993.
苯乙烯基-β-萘噻唑染料电子光谱的含时密度泛函研究   总被引:6,自引:0,他引:6  
对苯乙烯基-β-萘噻唑染料系列用量子化学密度泛函方法(DFT)在B3LYP/6-31g水平上进行了几何构型全优化, 探讨了苯环对位上不同的取代基CH3, OCH3, N(CH3)2, 3,4-OCH2O, NO2等对分子电荷转移、前线轨道能量和电子光谱等性质的影响规律, 在此基础上采用含时密度泛函方法(TD-DFT)计算了分子第一激发态的电子跃迁能, 得到最大吸收波长λmax. 计算结果表明, 上述5种取代基的引入, 均导致最大吸收波长红移. 与实验λmax结果相比, 理论计算最大相对偏差为0.0501, 最小相对偏差为0.0085.  相似文献   
994.
本文对波导染料自发辐射放大器进行了理论和实验研究。利用矩形波导模型求出波导模式、放大自发辐射阈值、放大自发辐射的近场及远场光强分布。实验获得放大自发辐射的远场光斑图样与理论计算比较基本一致,并对放大自发辐射输出特性进行研究。  相似文献   
995.
用紫外扫描吸收光谱、电化学循环极化、腐蚀电位监测和恒电位电解等方法研究了催化铁氧腐蚀电池处理活性艳红X-3B的电化学机理.结果表明,活性艳红X-3B在铁氧腐蚀电极上发生电化学还原而分解成小分子,达到脱色的目的,但模拟废水COD下降不大,电极反应过程属扩散步骤控制.  相似文献   
996.
以乙酸丁酯和正庚烷作为致孔剂,乙酸乙烯酯与异氰酸三烯丙基酯进行悬浮共聚、经碱性水解得到大孔交联聚乙烯醇树脂。交联聚乙烯醇与环氧氯丙烷在碱性条件下反应,得到含有环氧基的树脂。含有环氧基的树脂与6-氨基己基-N'-辛巴蓝F3G-A反应,制得固载辛巴蓝F3G-A (一种三嗪染料) 的交联聚乙烯醇树脂。将固载辛巴蓝F3G-A的交联聚乙烯醇树脂作为亲和色谱填料,对五种蛋白质 (细胞色素c、溶菌酶、牛血清白蛋白、胰岛素和乳酸脱氢酶) 进行了色谱分离。  相似文献   
997.
We have studied the pore size dependences of association processes for dye molecules incorporated into the matrix of a porous silicate glass. We have determined the structures of the associates of dye molecules as a function of the type of dye, the dye concentration, and the matrix pore sizes. We have established a nonuniform distribution of the complex dye molecules in the porous glass matrix, which is responsible for the higher efficiency of the association processes for the adsorbed molecules compared with alcoholic solutions of these dyes. __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 6, pp. 824–827, November–December, 2006.  相似文献   
998.
An amphiphilic block copolymer of acrylamide and butadiene was synthesized by the polymerization of acrylamide in the presence of the crosslinker N,N′‐methylene bisacrylamide initiated by a hydroxyl‐terminated polybutadiene/V(V) macroredox initiator. The product had good film‐forming ability. It was characterized by IR and NMR spectroscopy, viscosity, swelling, and microhardness measurements, scanning electron micrography, and differential scanning calorimetry. A good film was obtained from the block copolymer with a greater proportion of butadiene; it had greater permeability for nonpolar solvents, and it was poorly permeable to water and other polar solvents. The film swelled in polar and nonpolar solvents and had almost the same capacity for the loading and release of hydrophilic and hydrophobic dyes. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3290–3303, 2006  相似文献   
999.
Using probability-type velocity equations as a base, the kinetics of the formation of molecular complexes of an excited molecule with alcohol associates is investigated. Particular emphasis is placed on the temperature dependence of the kinetics of complexation. Theoretical deductions are compared with the results of an experiment. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 2, pp. 155–163, March–April, 1997.  相似文献   
1000.
With laser scanning confocal fluorescence microscopy, we demonstrate a novel type of morphology evolution in moderately thick films (70–100 μm) of ternary blends of polypropylene (PP), polyethylene (PE), and ethylene–propylene rubber (EPR), in which EPR is labeled with a benzothioxanthene dye (HY‐EPR). The blends are prepared by solution blending, and the phase morphology evolves during the annealing of the blend films in a stainless steel mold. Our results indicate that wetting of the mold surface is a driving force in morphology evolution for the two blend compositions investigated. For 81/14/5 PP/PE/HY‐EPR, phase evolution within the mold results in a laminar structure and hydrodynamic channels, features which have previously been found in thin films of polymer blends as a result of surface‐directed spinodal decomposition. In a blend with a lower weight fraction of the dispersed phase (92/7/1 PP/PE/HY‐EPR), we find that the PE/HY‐EPR domains are larger and more polydisperse closer to the surface because of wetting of the mold wall. We also show that the phase morphology in these films can be controlled by the nature of one or both of the surfaces being varied. When one of the mold surfaces is replaced with a thin film of PP homopolymer, we observe draining of PE/HY‐EPR from the PP to the mold surface, which results in a bilayer structure. A trilayer morphology is likewise obtained by the replacement of both mold surfaces with PP. We also carry out three‐dimensional image reconstruction on a single PE/HY‐EPR particle within the 81/14/5 PP/PE/HY‐EPR blend to obtain detailed information on the interphase structure. We find that HY‐EPR of this composition (30/70 ethylene/propylene) fully coats the PE dispersed phase and partially penetrates the PE droplets. This result falls between the interphase structures found for previously investigated EPR compositions (40/60 and 80/20 ethylene/propylene). © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 637–654, 2003  相似文献   
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