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建立了山茶油中黄曲霉毒素B1含量的高效液相色谱-串联质谱分析方法。通过对前处理方法的优化,选择了甲醇和水作为山茶油中黄曲霉毒素B1的提取溶剂,经免疫亲和柱富集浓缩后,采用高效液相色谱-串联质谱进行分析,经C18色谱柱分离,在电喷雾离子化正离子模式(ESI+)及多反应监测模式(MRM)下进行测定,基质匹配标准溶液外标法定量。在优化条件下,该方法线性范围为0.4~6.4μg/L,相关系数r2>0.998,最低检出限为0.026μg/kg,在添加水平为0.008,0.016和0.032μg时,方法回收率在85.9%~93.8%之间;相对标准偏差为1.8%~5.0%。方法可满足山茶油中黄曲霉毒素B1的检测要求。 相似文献
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A new coordination polymer [Cd2(5-IPA)(HL)2(H2O)2]·4H2O(1) was prepared under hydrothermal conditions based on 5-hydroxy-isophthalic acid(5-H2IPA) with multi-N-donor ligand 1-(1H-imidazol-4-yl)-3-(4H-tetrazol-5-yl)benzene(H2L). The complex was characterized by IR spectroscopy, TGA, X-ray powder and single-crystal diffraction. It crystallizes in the monoclinic system, space group C2/c with a = 23.6291(18), b = 9.9847(8), c = 17.7244(14) ?, β = 124.6180(10)?, V = 3441.4(5) ?3, Z = 4, C28H30N12O11Cd2, Mr = 935.44, Dc = 1.805 g/cm3, μ = 1.313 mm-1, S = 1.055, F(000) = 1864, the final R = 0.049 and w R = 0.1315 for 2985 observed reflections(I 2σ(I)). The central metal Cd(II) atoms with octahedral coordination geometry are six-coordinated by three oxygen and three nitrogen atoms. The HL- ligands from the deprotonated H2 L connect Cd(II) atoms to form two-dimensional(2D) double-layer fes networks which are further pillared by 5-IPA2- ligands into a rare binodal(3, 4)-connected three-dimensional(3D) architecture with a(4·6·8)(4·62·83) fsc-3,4-C2/c topology. Solid state luminescent property and sorption property of 1 have been investigated. 相似文献
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Hydride generation atomic fluorescence spectrometry (HG-AFS) is used for the determination of hydride-forming elements due to its high sensitivity, simplicity, and low cost. A new HG-AFS method for the simultaneous determination of arsenic and lead in vegetable oil is reported. Vortex-assisted extraction with dilute nitric acid was used to isolate arsenic and lead from vegetable oil. The conditions influencing the fluorescence signal, including the carrier fluid, oxidizing agent, and reducing agent, were optimized. The interferences of coexisting ions were also evaluated. Under the optimized conditions, the limits of detection were 0.6 and 0.4?µg?kg?1 for arsenic and lead. The recoveries were from 84.4 to 105% for both metals in vegetable oil. The optimized method was used for the determination of arsenic and lead in commercial vegetable oil. The analytical results by this approach were in good agreement with values obtained by inductively coupled plasma mass spectrometry with microwave digestion. 相似文献
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Zhimei Tian Na Zhang Chongfu Song Chang Wang 《International journal of quantum chemistry》2024,124(1):e27262
The interaction behavior of HCl and (ZnS)n (n = 1–12) clusters and HCl effect on Hg0 adsorbed by (ZnS)n have been studied theoretically. The combined genetic algorithm and density functional theory (GA-DFT) method has been used to obtain the structures of (ZnS)nHCl and (ZnS)nHgHCl (n = 1–12) clusters. The structural properties of (ZnS)nHCl and (ZnS)nHgHCl have been analyzed. The adsorption energies and interaction energies have been calculated. Bond length and bond order analysis has revealed that S H and Zn Cl bonds form after HCl adsorbed on (ZnS)n clusters, while Hg0 can only weakly bind with (ZnS)nHCl clusters. According to thermodynamic adsorption analysis, the formation of (ZnS)nHCl clusters from (ZnS)n and HCl are spontaneous because of their negative Gibbs free energy changes. The formation of (ZnS)nHgHCl from (ZnS)nHCl and Hg are nonspontaneous for n = 1–4 and 9, and the Gibbs free energy changes have small negative values for other sizes. Electron localization function and noncovalent interaction (NCI) analysis of (ZnS)10HgHCl manifest that Hg and its nearest Zn form zinc amalgam. Projected density of state study has been performed to obtain the interaction nature of HCl and (ZnS)n clusters and Hg0 adsorption on (ZnS)nHCl clusters. Based on our study, HCl is chemical adsorbed by (ZnS)n clusters except (ZnS)4 cluster. After (ZnS)n adsorbs HCl, Hg0 can physically adsorb on (ZnS)nHCl clusters. The strength of Hg0 on (ZnS)nHCl is comparable to that of Hg0 on (ZnS)n, indicating that HCl can hardly affect the adsorption of Hg0 on ZnS clusters. 相似文献
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离心破乳-气相色谱法测定黑米中残留抑霉唑的研究 总被引:1,自引:0,他引:1
报道了离心破乳-气相色谱法测定黑米中残留抑霉唑的方法. 考察了不同离心速率、不同离心时间的破乳效率. 试样以V(正己烷):V(乙酸乙酯)=1:1提取, 经毛细管气相色谱柱HP-5 (30 m×0.25 mm×0.25 μm)分离, μ-ECD检测器测定. 方法检出限为1.0×10-3 mg/kg (S/N=3). 在添标水平0.05、 0.25和0.50 mg/kg时的平均回收率为92.3%~104.3%, 相对标准偏差为6.9%~9.3%. 线性范围为0.02~1.0 mg/L (r2=0.9994). 方法适合黑米中残留抑霉唑的测定. 相似文献