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801.
802.
A three-component hydrogen-bonded covalent organic polymer, namely JLUE-HCOP-66, was fabricated via a facile multiple-linking-site solvothermal approach to overcome the weakness of poor function complexity and limited structure diversity of the pure covalent skeletons. The as-prepared JLUE-HCOP-66 polymers were employed to decontaminate ciprofloxacin (CIP), a popular F-quinolones (FQNs) antibiotic, from water and exhibited satisfactory adsorption performance. Specifically, JLUE-HCOP-66 polymers have high adsorption capacity with the maximum contribution of 111.1 mg/g according to the Langmuir model, good antiinterference to NaCl salts, and excellent regeneration property. The pH-dependent experiment results signified the probably dominated mechanism of electrostatic interaction. In addition, adsorption studies and structural characterization in combination illustrated that the pore-filling effect, hydrogen bonding formation might also govern the whole process, accompanied by electrostatic interaction, dipole-dipole complexation, π-π EDA interaction, and hydrophobic-hydrophobic interaction besides. Moreover, electrostatic potentials, as well as the frontier molecular orbital distributions (HOMO and LUMO) of CIP and JLUE-HCOP-66 fragment, were calculated using density functional theory to theoretically support the research. Furthermore, the response surface methodology (RSM) according to the CCD matrix was used to not only study the interactive and cooperative effects of initial CIP concentration, initial pH, ionic strength along with JLUE-HCOP-66 dosage on CIP removal using JLUE-HCOP-66 but also optimize the operation conditions. Given the peculiar structure and functional feature, this work could hopefully bring HCOPs into the practical applications of such challenging and persistent ciprofloxacin potent removal with further large-scale efficiency. 相似文献
803.
顶空气相色谱法测定瑞替加滨原料药中残留溶剂 总被引:1,自引:0,他引:1
建立了测定瑞替加滨原料药中残留溶剂乙醇、正己烷、四氢呋喃、三乙胺的顶空气相色谱方法。采用氢火焰离子化检测器,以N,N-二甲基甲酰胺为样品溶剂,通过对色谱条件优化,建立了以DB-624为分析柱、110℃为平衡温度、15 min为平衡时间的残留溶剂测定方法。经方法学验证,上述4种溶剂的方法检出限依次为0.007 5%、0.000 48%、0.002 4%、0.01%;峰面积的相对标准偏差均小于2.1%;平均回收率为100%~102%;4种溶剂的线性系数均大于0.995。结果表明,该方法的检测灵敏度高、精密度好、准确度高、线性关系良好,能够满足对瑞替加滨质量的控制要求。将该方法应用于3批瑞替加滨原料药的残留溶剂检测,均只检出乙醇和正己烷,且乙醇和正己烷的最高残留量分别为0.149%和0.022%,均未超出限量规定。 相似文献
804.
磷在氧化锆-碳纳米管复合材料上的吸附研究 总被引:2,自引:2,他引:2
采用水热合成法成功制备了氧化锆-碳纳米管复合材料,并研究了对磷的吸附行为。表征结果表明,碳纳米管经氧化锆修饰后仍具备介孔结构;氧化锆粒子可均匀分散在碳纳米管表面。吸附实验结果表明,氧化锆粒子的粒径越小,氧化锆对磷的标化平衡吸附量越高,吸附速率越快。磷在氧化锆-碳纳米管复合材料上的吸附等温线符合Freundlich等温吸附模式,属于优先吸附,吸附动力学可用拟二级动力学模型描述。降低离子强度和溶液pH可促进磷的吸附,共存离子对磷吸附具有抑制作用,影响顺序依次为F->NO3-≈SO42-,其中F-影响最大,NO3-和SO42-次之。 相似文献
805.
806.
807.
采用柠檬酸法制备了LaMnO3、LaFeO3、La0.5Sr0.5MnO3、La0.5Sr0.5FeO3,通过负载纳米Pt合成了Pt负载钙钛石催化剂,XRD与IR数据表明合成的催化剂具有钙钛石相,TEM数据表明合成的纳米Pt粒径为~3 nm,均匀分散在钙钛石上。在CO氧化反应中,发现钙钛石的氧化-还原性能是影响其活性的重要因素,因而,Mn系钙钛石表现出较高的CO氧化活性。负载纳米Pt后,Fe系钙钛石则显示出更优异的CO氧化活性,CO完全转化的温度从350 ℃降至120 ℃。吸附实验表明钙钛石上氧空位对促进O2的吸附起着非常重要的作用,也是影响CO低温氧化的重要因素之一。 相似文献
808.
A new cyano-substituted diarylethene derivative (R-NH2) with reversible far-red mechanofluorochromic property was synthesized and confirmed by standard spectroscopic methods. To the best of our knowledge, the 684 nm red-shifted wavelength of the ground R-NH2 is the longest wavelength that has appeared in the literature. The mechanofluorochromic mechanism was investigated by small and wide-angle X-ray scattering and was ascribed to the destruction of crystalline structure. More in-depth study by infrared spectra and time-resolved emission-decay behaviors showed that the changes of C–H out-of-plane bending vibrations in aryl group of the compound and the obvious increase of fluorescence lifetime might be the fundamental reasons. The synthetic strategy reported here can be extended to prepare more and more long-wavelength emission mechanofluorochromic materials, which can broaden the scope of application of such materials and for thoroughly understanding the mechanofluorochromic mechanism. 相似文献
809.
810.
Dr. Yaqi Jiang Yanyan Jia Jiawei Zhang Lei Zhang Huang Huang Prof. Dr. Zhaoxiong Xie Prof. Dr. Lansun Zheng 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(9):3119-3124
Pt? Cu alloy octahedral nanocrystals (NCs) have been synthesized successfully by using N,N‐dimethylformamide as both the solvent and the reducing agent in the presence of cetyltrimethylammonium chloride. Cu underpotential deposition (UPD) is found to play a key role in the formation of the Pt? Cu alloy NCs. The composition in the Pt? Cu alloy can be tuned by adjusting the ratio of metal precursors in solution. However, the Cu content in the Pt? Cu alloy NCs cannot exceed 50 %. Due to the fact that Cu precursor cannot be reduced to metallic copper and the Cu content cannot exceed 50 %, we achieved the formation of the Pt? Cu alloy by using Cu UPD on the Pt surface. In addition, the catalytic activities of Pt? Cu alloy NCs with different composition were investigated in electrocatalytic oxidation of formic acid. The results reveal that the catalytic performance is strongly dependent on Pt? Cu alloy composition. The sample of Pt50Cu50 exhibits excellent activity in electrocatalytic oxidation of formic acid. 相似文献