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911.
The title compound naphthalen-2-yl-4-methyl-1,2,3-thiadiazole-5-carboxylate (C 14 H 10 N 2 O 2 S,M r=270.31) was synthesized by the reaction of 4-methyl-1,2,3-thiadiazole-5-carbonyl chloride with 2-naphthol,and its structure was characterized by IR,1 H NMR,high-resolution mass spectrometry and single-crystal X-ray diffraction.The crystal belongs to orthorhombic,space group Pbcn with a=23.475(5),b=9.6640(19),c=10.814(2),β=90.00°,Z=8,V=2453.2(9) 3,M r=270.30,D c=1.464 g/cm 3,μ=0.262 mm-1,F(000)=1120,R=0.0444 and wR=0.1099.X-ray analysis revealed that the thiadiazole and naphthalene rings were non-planar,while the thiadiazole ring and the ester group were essentially planar,and two intermolecular hydrogen bonds C(6) H(6)···O(1) and C(14) H(14)···O(1) were observed.The preliminary biological test showed that the title compound had antifungal and antivirus activities against tobacco mosaic virus. 相似文献
912.
Rancan M Newton GN Muryn CA Pritchard RG Timco GA Cronin L Winpenny RE 《Chemical communications (Cambridge, England)》2008,(13):1560-1562
Synthetic and structural studies of Cr horseshoes are reported which show that these compounds demonstrate a rich supramolecular chemistry through H-bonding interactions, and can act as ligands for metal clusters. 相似文献
913.
采用分子全息定量构效关系(HQSAR)方法, 构建苯并咪唑衍生物在酸性环境中的缓蚀性能与结构之间的定量构效关系模型, 研究不同碎片区分参数及碎片大小对模型质量的影响, 寻找最优HQSAR模型, 并对其稳定性及预测能力进行评价. 结果显示: 选取碎片区分参数为原子类型(A)、化学键类型(B)、连接性(C)、氢原子(H)、手性(Ch)、氢键给体和受体(D&;A), 碎片大小为1-3 建模时, 得到的HQSAR 模型(r2(非交叉验证系数)=0.996, q2(交叉验证系数)=0.960, SEcv(交叉验证标准误差)=3.709)具有良好的统计学稳定性及预测能力. 根据最优HQSAR模型图设计出的38种苯并咪唑类化合物理论上均具有较好的缓蚀性能. 本研究为油气田新型高效缓蚀剂研发提供可靠的理论依据. 相似文献
914.
Kayla J. Pyper David K. Kempe Jade Y. Jung Li-Hsing J. Loh Nigel Gwini Benjamin D. Lang Brittney S. Newton Jonathan M. Sims Vladimir N. Nesterov Gregory L. Powell 《Journal of Cluster Science》2013,24(3):619-634
Microwave heating allows for the high-yield, one-step synthesis of the known triosmium complexes Os3(μ-Br)2(CO)10 (1), Os3(μ-I)2(CO)10 (2), and Os3(μ-H)(μ-OR)(CO)10 with R = methyl (3), ethyl (4), isopropyl (5), n-butyl (6), and phenyl (7). In addition, the new clusters Os3(μ-H)(μ-OR)(CO)10 with R = n-propyl (8), sec-butyl (9), isobutyl (10), and tert-butyl (11) are synthesized in a microwave reactor. The preparation of these complexes is easily accomplished without the need to first prepare an activated derivative of Os3(CO)12, and without the need to exclude air from the reaction vessel. The syntheses of complexes 1 and 2 are carried out in less than 15 min by heating stoichiometric mixtures of Os3(CO)12 and the appropriate halogen in cyclohexane. Clusters 3–6 and 8–10 are prepared by the microwave irradiation of Os3(CO)12 in neat alcohols, while clusters 7 and 11 are prepared from mixtures of Os3(CO)12, alcohol and 1,2-dichlorobenzene. Structural characterization of clusters 2, 4, and 5 was carried out by X-ray crystallographic analysis. High resolution X-ray crystal structures of two other oxidative addition products, Os3(CO)12I2 (12) and Os3(μ-H)(μ-O2CC6H5)(CO)10 (13), are also presented. 相似文献
915.
Kelsey L. Horvath Dr. Christopher G. Newton Dr. Kimberley A. Roper Dr. Jas S. Ward Prof. Michael S. Sherburn 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(16):4072-4076
The first general synthesis of compounds of the tetravinylethylene (TVE) family is reported. Ramirez-type dibromo-olefination of readily accessible penta-1,4-dien-3-ones generates 3,3-dibromo[3]dendralenes, which undergo twofold Negishi, Suzuki–Miyaura or Mizoroki–Heck reactions with a wide variety of olefinic coupling partners. This route delivers a broad range of unsymmetrically substituted tetravinylethylenes with up to three different alkenyl substituents attached to the central C=C bond. The extensive scope of the approach is demonstrated by the preparation of the first higher order oligo-alkenic through-conjugated/cross-conjugated hybrid compounds. An unsymmetrically substituted TVE is shown to undergo a domino electrocyclization–cycloaddition with high site-selectivity and diastereoselectivity, thereby demonstrating the substantial synthetic potential of substituted TVEs for controlled, rapid structural complexity generation. 相似文献
916.
以五氧化二磷和柠檬酸为原料,采用自催化法快速制备了磷掺杂的碳量子点(P-CDs),通过透射电镜、红外光谱、X射线光电子能谱、紫外和荧光光谱对其进行表征。结果表明,P-CDs的粒径在5.0~10.2 nm范围内,表面含有羟基、羧基和含磷官能团。基于金丝桃苷(HP)对P-CDs的荧光猝灭作用,建立了一种检测HP的新方法。该方法具有高的选择性和灵敏度。在优化条件下,HP对P-CDs的荧光猝灭率(I_(F0)/I_F)与HP的浓度在0.22~55μmol/L范围内呈良好的线性关系,检出限为78 nmol/L。该方法被成功用于药品复方木鸡颗粒中HP的检测,回收率为93.3%~107%,相对标准偏差为1.5%~1.7%。 相似文献
917.
Takuya Shiga Ryo Saiki Lisa Akiyama Reiji Kumai Dominik Natke Franz Renz Jamie M. Cameron Graham N. Newton Hiroki Oshio 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(17):5714-5718
A mononuclear FeII complex, prepared with a Brønsted diacid ligand, H2L (H2L=2‐[5‐phenyl‐1H‐pyrazole‐3‐yl] 6‐benzimidazole pyridine), shows switchable physical properties and was isolated in five different electronic states. The spin crossover (SCO) complex, [FeII(H2L)2](BF4)2 ( 1A ), exhibits abrupt spin transition at T1/2=258 K, and treatment with base yields a deprotonated analogue [FeII(HL)2] ( 1B ), which shows gradual SCO above 350 K. A range of FeIII analogues were also characterized. [FeIII(HL)(H2L)](BF4)Cl ( 1C ) has an S=5/2 spin state, while the deprotonated complexes [FeIII(L)(HL)], ( 1D ), and (TEA)[FeIII(L)2], ( 1E ) exist in the low‐spin S=1/2 state. The electronic properties of the five complexes were fully characterized and we demonstrate in situ switching between multiple states in both solution and the solid‐state. The versatility of this simple mononuclear system illustrates how proton donor/acceptor ligands can vastly increase the range of accessible states in switchable molecular devices. 相似文献
918.
苯并咪唑类缓蚀剂的3D-QSAR研究及分子设计 总被引:1,自引:0,他引:1
采用比较分子场分析法(CoMFA)和比较分子相似性指数分析法(CoMSIA), 对苯并咪唑衍生物抗盐酸腐蚀的缓蚀性能进行了三维定量构效关系研究, 并使用留一法交叉验证手段对3D-QSAR模型的稳定性及预测能力进行了分析. 结果表明, 立体场、静电场和氢键供体场(电子给体)是影响苯并咪唑缓蚀剂缓蚀性能的主要因素; 所构建的CoMFA模型(q2=0.541, R2=0.996)和CoMSIA模型(q2=0.581, R2=0.987)均具有较好的统计学稳定性和预测能力. 基于3D-QSAR等势图设计出了几种具有较好缓蚀性能的苯并咪唑化合物, 为油气田新型缓蚀剂的研发提供了一种新思路. 相似文献
919.
920.
MnO_x/TiO_2催化剂由于具有优异的低温脱硝性能,已成为SCR催化剂的研究热点之一.我们通过浸渍法制备了一系列不同Mn负载量的nMnO_x/TiO_2(n=2.5%, 5%, 10%, 15%)(质量分数)催化剂,考察Mn负载量对催化剂脱硝性能的影响.利用N_2物理吸附, X-Ray Diffraction (XRD), Scanning Electron Microscope(SEM),Temperature Programmed Reduction with H_2(H_2-TPR),Temperature Programmed Desorption with NH_3(NH_3-TPD)和X-Ray Photoelectron Spectroscopy (XPS)对其结构进行表征.结果表明,催化剂的脱硝性能随着Mn负载量(2.5%~15%)(质量分数)的变化呈现"火山型"曲线,当Mn负载量为10%(质量分数)时,催化剂的脱硝性能最佳. H_2-TPR和XPS结果表明nMnO_x/TiO_2催化剂上表面氧比例和表面Mn~(4+)浓度均随着Mn负载量的增大,先增大后减小,具体顺序为10MnO_x/TiO_(2 ) 15MnO_x/TiO_(2 )5MnO_x/TiO_(2 ) 2.5MnO_x/TiO_2,与脱硝性能顺序完全一致.进一步关联表面氧的比例与T_(50)发现,催化剂的表面氧的比例与T_(50)呈线性关系,即表面氧比例越高, T_(50)越小,脱硝活性越高. NH_3-TPD结果表明,弱酸酸量的增加有助于低温脱硝活性的提高.这些结果揭示了Mn负载量影响脱硝性能的作用规律,为今后开发高效的锰基低温脱硝催化剂提供了技术支撑. 相似文献