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Hong Zhu * Patrick Phelan Tianhua Duan Gregory Raupp H. J. S. Fernando Beijing Institute of Microbiology Epidemiology Beijing P. R. China Department of Mechanical Aerospace Engineering Arizona State University Tempe Department of Chemical Materials Engineering Arizona State University Tempe *Author to whom correspondence should be addressed. Tel: -- E-mail: zhuhong@hotmail.com 《中国颗粒学报》2003,1(3):119-123
1.IntroductionBioaerosolsaremicroorganismsorparticles,gases,vapors,orfragmentsofbiologicalorigin(i.e.,aliveorreleasedfromalivingorganism)thatexistintheair.Bioaerosolsareeverywhereintheenvironment.Underfavorableconditions,bioaerosolsareabletogrowandpropagateonavarietyofbuildingmaterialsandindoorsurfaces,causingindoorairpollution.Therefore,owingtotheirubiquitouspresenceinnature,bioaerosolsasapollutionsourcearealmostinevitableinarangeofenclosedenvironmentsandincommunityair(Kodama&McGee,1986;Lig… 相似文献
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Ruoyu Hong * Jianmin Ding Guoliang Zheng College of Chemistry Chemical Engineering Soochow University Suzhou P. R. China Institute of Process Engineering Chinese Academy of Sciences Beijing P. R. China IBM HYDA/- C Highway North Rochester MN USA *Author to whom correspondence should be addressed. E-mail: rhong@suda.edu.cn 《中国颗粒学报》2004,2(5):207-214
1. Introduction1.1 Silica nanoparticles and synthesis methods Silica (SiO2) nanoparticles are widely used in industry asan active filler for polymer reinforcement, a rheologicaladditive in fluids, a free flow agent in powders, and anagent for chemical mechanical polishing during IC (inte-grated circuit) fabrication (Sniegowski & de Boer, 2000).Silica powder is also used for producing silicon carbide(Koc & Cattamanchi, 1998) or opaque silica aerosols (Leeet al., 1995). Many methods can … 相似文献
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用密度泛函理论(DFT)的B3LYP方法在相对论有效实势(RECP)(O/6-311++g(d,p), V/lanl2dz)水平上对气态VOx(x=1-5)分子的几何构型, 振动频率, 电子亲和势和能级分布进行了理论研究. 通过对基态结构的几何参数分析发现, 它们的基态结构趋于立体结构. 其基态结构为: VO (4Σ), VO2 (2A1), VO3 (2A), VO4 (2A2), VO5 (4B2) . 对基态结构的垂直电离能, 电子性质和能级分布研究分析表明: 该系列分子最稳定的是VO4, 最不稳定的是VO. 该系列分子基态的平均VO键键长随氧原子数的增加而增长. 相似文献
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Hydrogen peroxide biosensor based on electrodeposition of zinc oxide nanoflowers onto carbon nanotubes film electrode 总被引:2,自引:0,他引:2
Hui Ping Bai Xu Xiao Lu Guang Ming Yang Yun Hui Yang~* Department of Chemistry Chemical Engineering Yunnan Normal University Kunming China 《中国化学快报》2008,19(3):314-318
A new amperometric biosensor for hydrogen peroxide was developed based on adsorption of horseradish peroxidase at the glassy carbon electrode modified with zinc oxide nanoflowers produced by electrodeposition onto multi-walled carbon nanotubes (MWNTs) film. The morphology of the MWNTs/nano-ZnO electrode has been investigated by scanning electron microscopy (SEM), and the electrochemical performance of the electrode has also been studied by amperometric method. The resulting electrode offered an excellent detection for hydrogen peroxide at -0.11 V with a linear response range of 9.9×10^-7 to 2.9×10^-3 mol/L with a correlation coefficient of 0.991, and response time 〈5 s. The biosensor displays rapid response and expanded linear response range, and excellent stability. 相似文献
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Jian Fang Zhong De Liang He~* Zhou Zhou Yi Bin Xu State Key Laboratory of Chemo/Biosensing Chemometrics College of Chemistry Chemical Engineering Hunan University Changsha China 《中国化学快报》2008,19(3):319-323
The similar electrochemical oxidation behaviors of hydroxypivalaldehyde in ionic liquids (ILs) medium, C4MIMPF6, C4MIMBF4 and CsMIMPF6, are investigated using classic electrochemical methods, respectively. Only the product, hydroxypivalic acid is detected by high performance liquid chromatography (HPLC). It can be conferred that the electrochemical oxidation of hydroxypivalaldehyde consists of two successive one-electron irreversible reactions at glass carbon (GC) electrode and the possible reaction mechanism in the ILs is proposed firstly. The diffusion coefficients of hydroxypivalaldehyde are obtained according to the electrochemical characteristics of hydroxypivalaldehyde in C4MIMPF6, C4MIMBF4 and CsMIMPF6. 相似文献
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1INTRODUCTIONInrecentyears,ourresearchgrouphasstudiedsystematicalycycloadditionreac tionsoftheC=Ndoublebondsinthebenzoheteroa... 相似文献
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The splitting of low-lying or low excited states for hydride molecules (cations) of the third period under spin-orbit coupling 下载免费PDF全文
This paper reports that the splitting of potential energy curves for the low-lying or low excited states for hydride molecules (cations) (MgH, AlH^+, SiH, PH^+, SH,ClH^+) of the third period under Spin-Orbit Coupling has been calculated by using the Spin-Orbit Multi-Configuration Quasi-Degenerate Perturbation Theory (SO-MCQDPT) method. Then, spectroscopic constants of the split states have been derived from the Murrell-Sorbie function. The calculated dissociation energies for the spectrum branch terms have been given, respectively. The spectroscopic constants and dissociation energies for the spectrum branch terms are given for the first time in this paper. 相似文献
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用文献[1,2,8]介绍的方法推导了N2分子的基态(X^1Σg^+)的激发态(A^3Σu^+和B^3Пg)的合理离解极限。计算并比较了在6-311G^*基集合,UHF、CID、UCISD和QCISD水平下N2分子上述三个电子态的平衡结构和谐振频率;并用QCISD/6-311G^*计算了各态的系列单点势能值,由正规方程组拟合Murrell-Sorbie函数得到了相应各态的完整势能函数,结果与实验数计 相似文献