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101.
全固态电池因其较高的安全性和能量密度而成为下一代电动汽车和智能电网用储能器件的重点研究方向之一。开发具有高室温锂离子电导率、化学/电化学稳定性优异、对电极材料兼容性优异等特点的固态电解质材料是推动全固态电池发展的重要研究课题之一。硫化物电解质因其相对较高的室温电导率(~10−3 S∙cm−1)、较低的电解质/电极固-固界面阻抗等优点而在众多无机固体电解质材料中成为研究热点。本文基于作者多年研究成果和当前国内外发表的相关工作,从电解质的结构、离子传导、合成、综合性能改善及在全固态电池中的应用等方面系统总结了锂硫银锗矿固态电解质材料研究,并分析了该类电解质面临的问题和挑战,最后探讨了其未来可能的研究方向和发展趋势。 相似文献
102.
首先研究高阶线性差分方程的整体收敛性,并证明了高阶非线性差分方程各阶导数的整体收敛;进而得到了关于高阶非线性差分方程整体收敛的一个定理,最后利用这个定理部分解决了Ladas提出的一个猜测。 相似文献
103.
The fluidized-bed polymerization process has been in use for decades. From the manufacturer's perspective it is desirable to improve technology without major modification of the reactor system. Therefore, in order to meet the demand for new products or more efficient reactor operation, manufacturers prefer to improve the catalyst system in the most cost effective manner. Using polypropylene production as an example, some recent advances in fluidized-bed polymerization technology are presented. 相似文献
104.
Weixin Zheng Yangfeng Wu Fenfen Zheng Linfeng Hu Ya Hong 《Tetrahedron letters》2010,51(36):4702-11640
α-Methylenyl zirconacyclopentenes are synthesized regio- and stereoselectively via reductive intermolecular cross-coupling of alkynes and allenes promoted by zirconocene species ‘Cp2Zr’. An interesting reductive intramolecular coupling of the α-methylenyl zirconacyclopentene has been observed in the presence of DMAD/CuCl, resulting in the generation of cyclobutene with an exocyclic double bond. Polysubstituted 1,4-dienes can be given with high selectivity and good yields. 相似文献
105.
The cationic polymerization of 1,3-pentadiene (PD) initiated by AlCl_3 in n-hexane was carried out. Effects of arenes, alkyl halides and ethers on the gel formation resulting from crosslinking reaction were investigated. The erosslinking was reduced by various arenes through a chain transfer mechanism. Alkyl halides such as tert-butyl chloride and allyl chloride could complex with AlCl_3 to generate an initiating system giving rise to a gel-free polymerization, while benzyl chloride reduced the formation of gel by chain transfer. Ethers exerted two effects on the polymerization system: giving a complex initiating system with AlCl_3 to produce a relatively high molecular weight polymer, or reducing crosslinking by lowering activity of carbocations. 相似文献
106.
107.
Zhishuo Wang Linfeng Jiang Jinwen Ji Fulin Zhou Jingbo Lan Prof. Dr. Jingsong You 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(52):23738-23742
Described herein is a strategy to construct cationic azahelicenes through the three-component annulation reaction of isoquinoline, indole, and 1,2-dichloroethane (DCE), in which DCE serves as an in situ activating agent for C1−H activation of isoquinoline, a vinyl equivalent, and a solvent. This in situ activation annulation reaction features a facile one-step synthesis and complete regioselectivity. The complete regioselectivity of C1 over C3 for the isoquinoline ring paves a path to the helical structure in a highly ordered sequence. One of the synthesized ionic [5]azahelicenium fluorophores exhibits the potential to serve as a mitochondria-targeted biomarker with good photostability and low cytotoxicity. 相似文献
108.
Within three functionals (TD-B3LYP, TD-BHandHLYP, and TD-CAM-B3LYP) in combination with four basis sets (3-21g, 6-31g, 6-31g(d), and cc-pvdz), global switching (GS) trajectory surface hopping molecular dynamics has been performed for cis-to-trans azobenzene photoisomerization up to the S1(nπ*) excitation. Although all the combinations show artificial double-cone structure of conical intersection between ground and first excited states, simulated quantum yields and lifetimes are in good agreement with one another; 0.6 (±5%) and 40.5 fs (±10%) by TD-B3LYP, 0.5 (±10%) and 35.5 fs (±4%) by TD-BHandHLYP, and 0.44 (±9%) and 35.2 fs (±10%) by TD-CAM-B3LYP. By analyzing distributions of excited-state population decays, hopping spots, and typical trajectories with performance of 12 functional/basis set combinations, it has been concluded that functional dependence for given basis set is slightly more sensitive than basis set dependence for given functional. The present GS on-the-fly time-dependent density functional theory (TDDFT) trajectory surface hopping simulation can provide practical benchmark guidelines for conical intersection driven excited-state molecular dynamics simulation involving in large complex system within ordinary TDDFT framework. © 2019 Wiley Periodicals, Inc. 相似文献
109.
Hui Liu Yanhong Xu Shihui Wen Qian Chen Dr. Linfeng Zheng Prof. Mingwu Shen Prof. Jinglong Zhao Prof. Guixiang Zhang Prof. Xiangyang Shi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(20):6409-6416
We report a facile approach to fabricating low‐generation poly(amidoamine) (PAMAM) dendrimer‐stabilized gold nanoparticles (Au DSNPs) functionalized with folic acid (FA) for in vitro and in vivo targeted computed tomography (CT) imaging of cancer cells. In this study, amine‐terminated generation 2 PAMAM dendrimers were employed as stabilizers to form Au DSNPs without additional reducing agents. The formed Au DSNPs with an Au core size of 5.5 nm were covalently modified with the targeting ligand FA, followed by acetylation of the remaining dendrimer terminal amines to endow the particles with targeting specificity and improved biocompatibility. Our characterization data show that the formed FA‐modified Au DSNPs are stable at different pH values (5—8) and temperatures (4–50 °C), as well as in different aqueous media. MTT assay data along with cell morphology observations reveal that the FA‐modified Au DSNPs are noncytotoxic in the particle concentration range of 0–3000 nM . X‐ray attenuation coefficient measurements show that the CT value of FA‐modified Au DSNPs is much higher than that of Omnipaque (a clinically used CT contrast agent) at the same concentration of the radiodense elements (Au or iodine). Importantly, the FA‐modified Au DSNPs are able to specifically target a model cancer cell line (KB cells, a human epithelial carcinoma cell line) over‐expressing FA receptors and they enable targeted CT imaging of the cancer cells in vitro and the xenografted tumor model in vivo after intravenous administration of the particles. With the simple synthesis approach, easy modification, good cytocompatibility, and high X‐ray attenuation coefficient, the FA‐modified low‐generation Au DSNPs could be used as promising contrast agents for targeted CT imaging of different tumors over‐expressing FA receptors. 相似文献
110.
基于介孔二氧化硅纳米颗粒的可控释放体系 总被引:2,自引:0,他引:2
基于介孔二氧化硅的控制释放体系具有良好的生物相容性、细胞靶向性、精准响应性控制释放和到达目标位点前有效阻止药物释放等功能特性。近年来,基于介孔二氧化硅的可控释放体系已成为众多科研工作者研究的热点。本文讨论了基于介孔二氧化硅纳米颗粒可控释放体系的特点,同时以不同的响应特性为主线,系统分析和总结了各种响应性介孔二氧化硅控释体系的开关及其控制释放机制,包括氧化还原控释系统、光控释系统、pH控释系统及生物分子相关控释系统等一系列基于介孔二氧化硅的控释系统,并对该领域未来的发展方向作了展望。 相似文献