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991.
Synthesis,Structures, and Luminescent Properties of Lanthanide Complexes with Triphenylphospine Oxide 下载免费PDF全文
Yan Ma Shan Xu Xin Wang Min Liu Yue‐Xue Li Xiu‐Lan Xin Qiong‐Hua Jin 《无机化学与普通化学杂志》2017,643(12):780-788
Seven lanthanide complexes [Ln(OPPh3)3(NO3)3] ( 1 – 3 ) (OPPh3 = triphenylphosphine oxide, Ln = Nd, Sm, Gd), [Dy(OPPh3)4(NO3)2](NO3) ( 4 ), [Ln(OPPh3)3(NO3)3]2 ( 5 – 7 ) (Ln = Pr, Eu, Gd) were synthesized by the reactions of different lanthanide salts and OPPh3 ligand in the air. These complexes were characterized by single‐crystal X‐ray diffraction analysis, elemental analysis, IR and fluorescence spectra. Structure analysis shows that complexes 1 – 4 are mononuclear complexes formed by OPPh3 ligands and nitrates. The asymmetric units of complexes 5 – 7 consist of two crystallographic‐separate molecules. Complex 1 is self‐assembled to construct a 2D layer‐structure of (4,4) net topology by hydrogen bond interactions. The other complexes show a 1D chain‐like structure that was assembled by OPPh3 ligands and nitrate ions through C–H ··· O interactions. Solid emission spectra of compounds 4 and 6 are assigned to the characteristic fluorescence of Tb3+ (λem = 480, 574 nm) and Eu3+ (λem = 552, 593, 619, 668 nm). 相似文献
992.
Two isomorphic organically templated zinc/cobalt oxalates, (dmdabco)[Zn2(C2O4)3]·4H2O (1), and (dmdabco)[Co2(C2O4)3]·4H2O (2) (C2O42? = oxalate; dmdabco = N,N′-dimethyl-1,4-diazabicyclo[2,2,2]octane), have been prepared under solvothermal conditions and characterized by X-ray structural analyses. The dmdabco2+ templating agent was derived from simple in situ N-alkylation between methanol and 1,4-diazabicyclo[2,2,2]octane (dabco). Distinct from conventional Eschweiler-Clarke methylation containing excess formic acid and formaldehyde, such one-step methylation from methanol molecules is convenient. Both 1 and 2 exhibit a uninodal 3-connected 3-D interrupted open-framework, in which oxalate ligands have in-plane and out-of-plane connection modes. 相似文献
993.
He Yanfang Niu Xiangheng Shi Libo Zhao Hongli Li Xin Zhang Wenchi Pan Jianming Zhang Xifeng Yan Yongsheng Lan Minbo 《Mikrochimica acta》2017,184(7):2181-2189
Microchimica Acta - The authors describe a photometric method for the determination of free cholesterol based on the oxidation of cholesterol by the catalytic action of the enzyme... 相似文献
994.
Wang Jia Liu Yuan Deng Xiling Zhao Na Ying Xue Ye Bang-Ce Li Yingchun 《Mikrochimica acta》2017,184(10):3893-3900
Microchimica Acta - The authors describe an electrochemical sensor for ultrasensitive voltammetric of histamine (HA) by using a gold electrode that was modified with a film consisting of... 相似文献
995.
A pyrene-based dual chemosensor for colorimetric detection of Cu2+ and fluorescent detection of Fe3+
Yuxin Guo Lei Wang Jiezhen Zhuo Bo Xu Xue Li Jianyu Zhang Zhiqiang Zhang Haijun Chi Yan Dong Gonghao Lu 《Tetrahedron letters》2017,58(42):3951-3956
A pyrene based chemosensor was designed and synthesized. The pyrene fluorophore was connected with a pyridine unit through a Schiff base structure to give the sensor (L). L was tested with a variety of metal ions and exhibited high colorimetric selectivities for Cu2+ and Fe3+ over other ions. Upon binding with Cu2+ or Fe3+, L showed an obvious optical color change from colorless to pink for Cu2+ or orange for Fe3+ over a wide pH range from 3 to 12. Moreover, the fluorescence of L at 370 nm decreased sharply after bonding with Fe3+, while other metal ions including Cu2+ had no apparent interference. Thus, using such single chemosensor, Cu2+ and Fe3+ can be detected independently with high selectivity and sensitivity. The limits of detection toward Cu2+ and Fe3+ were 8.5 and 2.0 μM, respectively. DFT calculation results also proved the formation of stable coordination complexes and the phenomenon of fluorescence quenching by Fe3+. Furthermore, L was also successfully used as a bioimaging reagent for detection of Fe3+ in living cells. 相似文献
996.
Ming-Qi Wang Zi-Yu Wang Yi-Fan Yang Gui-Ying Ren Xiao-Ning Liu Shuo Li Jian-Wei Wei Lan Zhang 《Tetrahedron letters》2017,58(33):3296-3300
The development of small-molecule G-quadruplex DNA probes has attracted significant attention in recent years. However, G-quadruplexes can display a wide variety of topologies, which process different structures and functions. Therefore, selective discrimination one G-quadruplex structure over another is promising. Herein, we reported the design, synthesis and biological evaluation of a long-chain fatty amine functionalized triphenylamine-quinolinium conjugate 1b. Significant enhancement of the fluorescence intensity (over 180 fold) was observed when 1b bound with HRAS G-quadruplex DNA, while much weaker enhancements were presented in the presence of other G-quadruplexes (45–90-fold) and single/double-stranded DNAs (less than 20-fold), indicating 1b had an excellent selectivity to HRAS. The details of the interactions were investigated by UV–Vis, FID and CD analysis. The results show 1b could interact and stabilize HRAS structure mainly by π-π stacking binding mode. The introduced amine chain of the structure core was found to be better in the terms of inducing selectivity toward G-quadruplex structure. In addition, the application of 1b as a fluorescent agent for living cell imaging was also demonstrated. 相似文献
997.
Immobilization of silver nanoparticles into POEGMA polymer brushes as SERS‐active substrates 下载免费PDF全文
Qian Zhang Jun‐Jiao Yin Feng Liu Xue‐Na Zou Li‐Qiang Chu 《Surface and interface analysis : SIA》2017,49(4):316-322
Surface‐enhanced Raman scattering (SERS) has attracted a great deal of interest during the past four decades and emerged as an ultrasensitive optical technique for chemical and biomedical analysis. It is widely accepted that the facile fabrication of SERS substrates with high activity and good reproducibility is of crucial importance for their applications. Herein, we report on a fast and robust method for the synthesis and immobilization of silver nanoparticles (AgNPs) into poly(oligo(ethylene glycol) methacrylate) (POEGMA) brushes under mild conditions without using any reducing agents. POEGMA brushes of different chain lengths were synthesized directly on silicon wafers by surface‐initiated atom transfer radical polymerization with various reaction time. X‐ray photoelectron spectroscopy and field emission scanning electron microscope measurements indicated that the AgNPs were firmly and homogeneously embedded into POEGMA brushes. The resulting POEGMA–AgNP hybrid films were employed as SERS substrates for the detection of 4‐aminothiophenol, giving rise to an enhancement factor of up to 1.9 × 106. The influence of the POEGMA's chain length on SERS performance was also investigated. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
998.
Danlu Xue Chunyi Liu Xiaomin Li Jie Tang Lihua Cao Yi Liu Zhengping Chen 《Journal of Radioanalytical and Nuclear Chemistry》2017,313(2):419-428
We studied on the structural requirement of C11b chirality of tetrabenazine (TBZ) analogs as vesicular monoamine transporter 2 (VMAT2) ligands. TBZ analogs (2, 6a, 6b) and 18F-radiolabeled [18F]6a and [18F]6b with eliminated C11b chirality were synthesized and characterized. Competition studies demonstrated that 2, 6a and 6b displayed much lower in vivo VMAT2 bindings than TBZ. MicroPET imaging studies of [18F]6a and [18F]6b showed negligible accumulation in VMAT2-enriched regions as compared with the known VMAT2 ligand 18F-FP-(+)-DTBZ. These results suggest that C11b chirality of TBZ analogs is essential for in vivo VMAT2 binding bioactivity. 相似文献
999.
Li Ruifen Cao Xiaojun Zhao Haogui Liu Chunxia Li Zheng Wang Jinhua Zhang Lan Li Qinguan 《Journal of Radioanalytical and Nuclear Chemistry》2017,314(3):1715-1725
Di-1-methyl heptyl methyl phosphonate (DMHMP) is a promising alternative extractant for Th-U fuel reprocessing, in which the irradiation stability of extractant should be systematically studied. In this paper, the radiolysis products of DMHMP were analyzed qualitatively and quantitatively with gas and ion chromatograph, the possible radiolysis mechanism of DMHMP was also concluded. Moreover, the effect of structure on the radiolysis products and irradiation stability of neutral organophosphorus compound extractant was also discussed.
相似文献1000.
多巴胺和L-精氨酸制备超轻氮掺杂石墨烯气凝胶吸油性能的研究 总被引:1,自引:0,他引:1
多巴胺和L-精氨酸制备超轻氮掺杂石墨烯气凝胶吸油性能的研究 《燃料化学学报》2017,45(10):1230-1235
采用水热法制备了超轻氮掺杂石墨烯气凝胶。分析表征结果表明,多巴胺不仅为还原剂而且提供氮源,石墨烯溶液前躯体的pH值对水热法制备超轻氮掺杂石墨烯气凝胶很大的影响,通过调节多巴胺和L-精氨酸在石墨烯溶液前躯体的浓度,可制备密度为2.54 mg/cm3超轻氮掺杂石墨烯气凝胶,由于氮掺杂、低密度和大的比表面积,超轻氮掺杂石墨烯气凝胶对各种油品都有良好的吸附性能。 相似文献