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991.
A New Capillary Electrophoresis Apparatus with Piezoelectric Ceramics High Voltage Source and Amperometric Detector 总被引:13,自引:0,他引:13
Zuan Guang CHENI Jin Yuan MO Xiao Yun YANG Li Shi WANG Xue Ting MEIZ Min Sheng ZHANGI 《中国化学快报》1999,(3)
IntroductionHighperformancecapiliar}'electrophoresis(HPCE)isanewanalyticaltechnology'rapidly'developedinrecentyears.Withtheadvantagesofsmallsample.highsensitivity,highresolution.rapidanalysisandverycheaprunning,ithasbeenappliedinchemistry'.lifescienc... 相似文献
992.
ZHANG Feng zhang ** XU Liang shu HUANG He qing LONG Min nan QIU Xue hui CHEN Zhong 《高等学校化学研究》1999,(3)
IntroductionNitrogenasefromavarietyofN2-fixingorganismsiscomposedoftwo-componentprotein,MoFe-proteinandFe-protein.Fe-proteincontainsasingleFe4S4-cluster,whichhasthefunctionoftransferingelectronsfromdonortoMoFe-protein.MoFe-proteincontainsP-clusterpai… 相似文献
993.
Xue Luo 《Colloid Journal》2009,71(2):281-284
We proposed an economic, convenient, and mild synthesis of dendrimer-protected gold nanoparticles by exposing a third-generation
poly(propyleneimine) dendrimer-HAuCl4 aqueous solution to sunlight without the additional step of introducing other reducing agents and protective agents. Most
importantly, it is found that the size of the gold nanoparticles thus formed can be controlled by the molar ratio of the dendrimer
to gold.
The text was submitted by the author in English. 相似文献
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997.
Zhigang Xue Rinaldo Poli 《Journal of polymer science. Part A, Polymer chemistry》2013,51(16):3494-3504
The radical polymerization of vinyl acetate (VAc) is moderated by iron(II) acetylacetonate (Fe(acac)2) by the organometallic route (OMRP), as well as by degenerative transfer polymerization (DTP) when in the presence of excess radicals, through the formation of thermally labile organometallic FeIII dormant species. The poly(vinyl acetate) (PVAc)‐FeIII(acac)2 dormant species has been isolated in the form of an oligomer and characterized by 1H NMR, EPR, and IR methods, and then used as a single‐component initiator for the OMRP of VAc. The degree of polymerization of this isolated oligomeric species demonstrates the limited ability of Fe(acac)2, relative to the Co(acac)2 congener, to rapidly trap the growing PVAc radical chain. Control under OMRP conditions is improved by the presence of Lewis bases, especially PMe2Ph. On the other hand, iron(II) phthalocyanine inhibits the radical polymerization of VAc completely. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 3494–3504 相似文献
998.
Zhiyong Gong Qingwen Liu Pengchong Xue Kechang Li Zhiguang Song Zaiqun Liu Yinghua Jin 《应用有机金属化学》2012,26(3):121-129
Several novel chiral thiazoline primary and tertiary alcohols were easily synthesized from commercially available l ‐cysteine in three steps and with high yield. These ligands were subsequently applied to the asymmetric addition of diethylzinc (Et2Zn) to various aldehydes. Products with S configuration were obtained when thiazoline‐containing tertiary alcohol ligands were used as catalysts. The primary alcohol induced corresponding products with R configuration in 68% enantiomeric excess, which was a higher value relative to other N―O ligands possessing a primary alcohol unit in the literature. Furthermore, a plausible transition state model was proposed to explain the observed enantioselectivities. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
999.
Shu Yin Peilin Zhnag Bin Liu Xiangwen Liu Tsugio Sato Dongfeng Xue Soo Wohn Lee 《Research on Chemical Intermediates》2010,36(1):69-75
Nitrogen-doped titania (TiO2−xNy) nanoparticles with monoclinic phase were successfully prepared by a microwave-assisted hydrothermal process. The obtained
TiO2−xNy powders showed high specific surface area, fine particle size, and excellent photocatalytic ability for the oxidative destruction
of nitrogen monoxide under irradiation of monochromatic LED light with various wavelengths. 相似文献
1000.
Yuexing Zhang Dongdong Qi Xue Cai Jianzhuang Jiang 《International journal of quantum chemistry》2010,110(8):1559-1564
The nature of the near‐IR band in the electronic absorption spectra of bis(tetrapyrrole) rare earth(III) complexes Y(Pc)2 (1), La(Pc)2 (2), Y(Pc)(Por) (3), Y(Pc)[Pc(α‐OCH3)4] (4), Y(Pc)[Pc(α‐OCH3)8] (5), and Y(Pc)[Pc(β‐OCH3)8] (6) was studied on the basis of time‐dependent density functional theory (TD‐DFT) calculations. The electronic dipole moment along the z‐axis in the electronic transition of the near‐IR band in all the studied neutral bis(tetrapyrrole) yttrium(III) and lanthanum(III) double‐deckers is well explained on the basis of the composition analysis of the orbitals involved. The electronic transition in the near‐IR band causes the reversion of the orbital orientation of one tetrapyrrole ring in both homoleptic and heteroleptic bis(tetrapyrrole) rare earth complexes and induces electron transfer from the tetrapyrrole ring with lower orbital energy to the other ring in the heteroleptic bis(tetrapyrrole) rare earth(III) complexes. The near‐IR band can work as an ideal characteristic absorption band to reflect the π–π interaction between the two tetrapyrrole rings in bis(tetrapyrrole) rare earth(III) double‐decker complexes because of its peculiar electronic transition nature. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010 相似文献