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971.
Photonic crystals are nanomaterials with unique structural coloration, and they have been used in multiple analyses, gene function analyses, and nanoarray biosensors. Here, we used agarose hydrogel microcarriers with characteristic reflection peak codes to improve the biocompatibility of the material and the efficiency of detection, which may be helpful for further clinical applications. The paper has two parts: condition optimization and product application. Goat antihuman immune globulin G, human immune globulin G, and fluorescein isothiocyanate-labeled goat antihuman immune globulin G are commonly used materials in double-antibody sandwich techniques, which are used for optimization in the application of advanced composite materials. Goat antihuman immune globulin G was immobilized on the surfaces of photonic crystal hydrogel beads through chemical bonding. When the target immune globulin G was captured, the fluorescence-labeled antibody could combine with photonic crystal hydrogel beads. The reaction conditions were optimized using the gray-scale value of fluorescent intensities. Photonic crystal hydrogel beads with different reflection spectra were coated with purified platelet glycoprotein IIb/IIIa and glycoprotein Ib/IX. A total of 64 clinical samples including sera from patients with immune thrombocytopenia (n?=?32) and healthy human sera (n?=?32) were tested using photonic crystal hydrogel beads and monoclonal antibody immobilization of platelet antigen (MAIPA). Photonic crystal hydrogel bead array reaction conditions were established for multiple analysis, showing similar sensitivity and specificity with MAIPA in testing different platelet antibodies and shortening the analysis time. The features of these composite materials make them suitable for potential applications in clinical screening assays.  相似文献   
972.
Fulton and Kraskiewicz gave a presentation of Specht modules as a quotient of the space of column tabloids by dual Garnir relations. We simplify this presentation by showing that it can be generated by a single relation for each pair of columns of a tableau with ordered columns, thereby significantly reducing the number of generators given in the original construction. Our presentation applies to all Specht modules, and is of a similar nature to a recent result by Friedmann-Hanlon-Stanley-Wachs that applies to staircase partitions. We show that our presentation implies the Friedmann-Hanlon-Stanley-Wachs presentation.  相似文献   
973.
用耐高温阳离子树脂催化二壬基酚与苯酚烷基转移为壬基酚.研究表明,经过耐温处理的强酸性阳离子交换树脂有较好的催化性能,当以CH2O2型树脂作为催化剂。在140℃,苯酚与二壬基酚摩尔比8:l的务件下反应2.5h,二壬基酚的转化率可以达到90%以上,适当延长反应时间。二壬基酚的转化率可以进一步提高,催化剂重复使用8次催化活性没有明显降低.  相似文献   
974.
The present study reports application of biphenyl-3,5-dicarboxylic acid (H2L) as a versatile building block for synthesis of d10 metal coordination polymers (CPs). Five Cd(II) and Zn(II)-containing CPs based on N,N-donor ancillary ligands, [Cd23-L)22-4,4′-tmbpy)(MeOH)] (1), [Cd(μ2-L)(2,2′-bpy)(H2O)]·n(MeOH) (2), [Cd(μ2-L)(dipt)] (3), [Cd(μ3-L)(phen)]·nH2O (4), and [Zn(μ2-L)(μ2-4,4′-tmbpy)]·nH2O (5) {4,4′-tmbpy = 4,4′-trimethylenedipyridine, 2,2′-bpy = 2,2′-bipyridine, dipt = 2,9-dimethyl-1,10-phenanthroline, phen = 1,10-phenanthroline} have been prepared under solvothermal conditions. 15 have been characterized by single crystal X-ray diffraction, elemental analysis, infrared (IR) spectra, and powder X-ray diffraction (PXRD). Complex 1 exhibits a three-dimensional (3-D) framework with a rare fsc-3,4-I41/amd topology. Complexes 24 show one-dimensional (1-D) structures. Complex 5 features a two-dimensional (2-D) layer structure with a sql topology. The structural and topological diversity of 15 are mainly attributed to the effect of the N,N-donor ancillary ligand. Solid-state luminescent properties and thermal stabilities of the obtained products have been investigated.  相似文献   
975.
9‐Fluorenylmethoxycarbonyl was a good protecting group in the field of chemical industry. In the present paper, a new approach for the synthesis of oxadiazine insecticides indoxacarb used 9‐fluorenylmethoxycarbonyl as protected group, and triphosgene for chloroformylation. A convenient synthesis of 9‐fluorenylmethoxycarbonylhydrazine can be achieved by the nucleophilic substitution reaction of 9‐fluorenylmethyl chloroformate and hydrazine hydrate. 4a‐Methyl‐2‐(9‐fluorenylmethyl)‐7‐chloro‐indeno [1,2e][1,3,4]oxadia zine‐2,4a (3H,5H)‐dicarboxylate can be produced via ketone ‐hydrazine crosslink reaction and cyclization. A preparation of carbamic acid‐(chlorocarbonyl)‐[(4‐trifluoromethoxy) phenyl] me ester can be obtained by the chloroformylation of triphosgene. Finally, the deprotection of 9‐fluorenylmethoxy carbonyl and condensation with carbamic acid‐(chlorocarbonyl)‐[(4‐trifluoromethoxy) phenyl] me ester can afford indoxacarb in good yield. A new method for the synthesis of oxadiazine insecticides indoxacarb used 9‐fluorenylmethoxycarbonyl‐protected group to produce 9‐?fluorenylmethoxycarb?onylhydrazine, then through the ketone–hydrazine crosslink reaction, cyclization, deprotection, chloroformylation, and condensation in good yield.  相似文献   
976.
977.
Aluminum nanoparticles synthesized by titanium (IV) isopropoxide-initiated decomposition of alane have been passivated and capped using oligomerization of 1,2-epoxyhexane. Preliminary synthetic protocols with this capping agent, where the nanoparticle formation reaction and passivation processes were both conducted at ambient temperatures, had resulted in nanoparticles that were highly unstable and that either oxidized rapidly upon exposure to air or were pyrophoric. Use of 1,2-epoxydodecane, on the other hand, had produced stable nanoparticles that were successfully characterized and reported. A modification of the procedure whereby the epoxyhexane passivation process is carried out at 85 °C for 30 min, has afforded surprisingly stable aluminum nanoparticles. Powder X-ray analysis and transmission electron microscopy reveal nanoparticle diameters on the order of 30 nm with 19 nm crystalline aluminum cores. The passivation process yields an extraordinarily high active aluminum (Al0) content of 83%, with degradation of the core to 52% active aluminum after 9 days exposure in a dry air chamber. Differential scanning calorimetry coupled with thermogravimetric analysis reveals distinct cap combustion and metal ignition exotherms, though they are not as well-defined as those found with their epoxydodecane-capped congener. With the additional observation of a metal melting endotherm, it is suggested that while carrying out the passivation process at an elevated temperature affords a higher degree of kinetic stabilization of the aluminum core, the passivation shell is inhomogeneous, possibly as a result of the polydisperse nature of the oligomerized epoxyhexane.  相似文献   
978.
ABSTRACT

Guanidinylated carboxymethyl chitosan (GCMCS) was prepared via the guanidinylation of carboxymethyl chitosan (CMCS). A device employing the diffusive gradients for thin films (DGT) technique was made using a GCMCS aqueous solution as the binding agent and a cellulose acetate dialysis membrane (CADM) as the diffusion phase to measure labile Cu2+, Pb2+ and Cd2+ in water. The percentage uptake (U%) values of labile Cu2+, Pb2+ and Cd2+ in a synthetic water sample were almost consistent with the theoretical values at 101.6 ± 2.8%, 104.6 ± 6.1% and 95.9 ± 4.4%, respectively. The optimum pH ranges for the measurement of labile Cu2+, Pb2+ and Cd2+ were 3.0–7.0, 3.0–7.0 and 4.0–8.0, respectively. The ionic strength mainly affected the diffusion of metal ions in the CADM. The diffusion rates decreased with increasing concentrations of NaNO3 solutions. The application of GCMCS-DGT in natural water and industrial wastewater showed that dissolved organic carbon (DOC) only affects metal species, and the accurate determination of labile Cu2+, Pb2+ and Cd2+ can be achieved when the diffusion coefficients of these metal ions in the diffusion phase have been determined. GCMCS is suitable for DGT application as a chelating agent for metal ions.  相似文献   
979.
采用溶剂热反应合成了一种二维钴基配位聚合物[KCo(pa)(OH)]n(Co-pa,H2pa=邻苯二甲酸),并对其进行了红外光谱、热重分析、粉末X射线衍射、X射线光电子能谱、扫描电镜和氮气吸附-脱附等温线表征。当Co-pa作为超级电容器电极材料时,Co-pa电极展示了较高的放电比容量、较好的循环稳定性和倍率性能。在1和10 A·g-1电流密度下,其比电容分别为910和400F·g-1。在2 A·g-1下循环2 000次后,其电容保持率为81.2%。较好的赝电容性能与Co-pa的小尺寸纳米棒形貌、Co-pa包含的钴离子、邻苯二甲酸根阴离子及层状结构有关。  相似文献   
980.
遗传算法作为一种随机化优化搜索方法,已经在很多领域得到了成功应用,但其存在控制参数多且配置困难的问题.本文采用一类最新试验设计方法-计算机试验设计,对遗传算法的参数配置进行优化.结果表明,基于正交拉丁超立方设计的参数配置,其算法的计算精度和速度表现最佳.模拟结果进一步讨论了不同试验设计方案在遗传算法中的差别.  相似文献   
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