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991.
NaSc3[HPO3]2[HPO2(OH)]6 was prepared by use of a phosphorus acid flux route. The crystal structure was determined from single‐crystal X‐ray diffraction data: triclinic, space group P$\bar{1}$ (No. 2), a = 7.4507(11) Å, b = 9.6253(17) Å, c = 9.6141(16) Å, α = 115.798(4)°, β = 101.395(4)°, γ = 101.136(3)°, V = 577.29(16) Å3 and Z = 1. The crystal structure of NaSc3[HPO3]2[HPO2(OH)]6 contains two kinds of phosphate(III) groups: HPO32– and HPO2(OH)–. Phosphate(III)‐tetrahedra, NaO6 and ScO6 octahedra together form a (3,6)‐connected net. During heating hydrogen and water are released and Sc[PO3]3 is formed as the main crystalline decomposition product. 相似文献
992.
Organohalogen compounds, principally brominated aromatics, continue to be the largest selling flame retardants worldwide. However, there is increasing concern about the bioaccumulation and potential toxicity of these compounds. Consequently, there is great interest in the development of effective alternatives to these materials. Organophosphorus compounds seem to offer the most promise as replacements for halogen-containing flame retardants. One approach to flame-retarding vinyl polymers is to develop reactive monomers containing high levels of phosphorus which may be incorporated directly into the polymer structure. Five phosphorus monomers for use in making fire-retardant copolymers with styrene have been synthesized. A comparative study of the thermal stability of the copolymers has been conducted. Preliminary potential fire behavior data have been obtained using pyrolysis combustion flow calorimetry. 相似文献
993.
Syed R. HaiderBarry L. Sharp Helen J. Reid 《Trends in analytical chemistry : TRAC》2011,30(11):1793-1808
The on-line coupling of gel electrophoresis with inductively coupled plasma-mass spectrometry (GE-ICP-MS) is a powerful tool for simultaneous separation, detection and quantification of bio-molecules, and has been applied to the determination of phosphorus in DNA, phosphoproteins, and phosphopeptides, gold in nano-particles, iron in metalloproteins, and iodine in aerosols, and cisplatin-oligonucleotide interactions. However, since the first report in 2005, relatively few papers have been published, perhaps reflecting the lack of familiarity with the benefits of this promising methodology. So, here for the first time, we critically review the applications of GE-ICP-MS, and explore the advantages and the limitations of the technique for various applications. Such scrutiny may be useful in not only the development of the technique but also highlighting its potential in proteomics, genomics and metallomics. 相似文献
994.
Prakash M Geetha D Caroline ML Ramesh PS 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,82(1):461-466
The mineral crandallite CaAl3(PO4)2(OH)5·(H2O) has been identified in deposits found in the Jenolan Caves, New South Wales, Australia by using a combination of X-ray diffraction and Raman spectroscopic techniques. A comparison is made between the vibrational spectra of crandallite found in the Jenolan Caves and a standard crandallite. Raman and infrared bands are assigned to PO43− and HPO42− stretching and bending modes. The predominant features are the internal vibrations of the PO43− and HPO42− groups. A mechanism for the formation of crandallite is presented and the conditions for the formation are elucidated. 相似文献
995.
996.
997.
以无机硫为原料制备硫化铅量子点及其表征 总被引:1,自引:0,他引:1
根据高温下快速成核低温下慢速生长的量子点制备原理, 采用胶体化学的方法成功制备了不同粒径的硫化铅半导体量子点. 这种方法的特点是以无味和低毒的硫化钠作为制备硫化铅量子点硫的前驱物, 因此这是一种量子点的绿色化学合成方法. 油酸作为稳定剂控制硫化铅的粒径. 采用X射线衍射和高分辨透射电镜表征了量子点的晶体结构、形貌和粒径, 采用可见-近红外吸收光谱研究了硫化铅量子点的量子尺寸效应. 通过降低油酸的添加量可以促进量子点的生长, 得到较大粒径量子点. 并探讨了量子点的生长机理. 相似文献
998.
用2.5%、5.0%和7.5% (w)的1,3-丙二醇(1,3-PDO)稀水溶液为模型物质, 以超临界二氧化碳为连续相, 以琥珀酸二酯磺酸钠(AOT)为表面活性剂, 乙醇为助剂, 在压力为6.9-10.3 MPa的范围内, 温度为30-50 °C时, 分别对三种AOT浓度下的四元体系AOT/CO2/乙醇/水和五元体系AOT/CO2/乙醇/1,3-PDO/水的热力学行为进行了实验研究. 实验结果证明: 通过合理调控系统的操作条件, 可以形成热力学稳定的超临界二氧化碳微乳液, 并能实现选择性增溶1,3-丙二醇. 该结果可为指导工业生产提供依据. 相似文献
999.
Yizhuan YanChau-Chyun Chen 《Fluid Phase Equilibria》2011,306(2):149-161
A comprehensive thermodynamic model based on the electrolyte NRTL (eNRTL) activity coefficient equation is developed for the NaCl + H2O binary, the Na2SO4 + H2O binary and the NaCl + Na2SO4 + H2O ternary. The NRTL binary parameters for pairs H2O-(Na+, Cl−) and H2O-(Na+, SO42−), and the aqueous phase infinite dilution heat capacity parameters for ions Cl− and SO42− are regressed from fitting experimental data on mean ionic activity coefficient, heat capacity, liquid enthalpy and dissolution enthalpy for the NaCl + H2O binary and the Na2SO4 + H2O binary with electrolyte concentrations up to saturation and temperature up to 473.15 K. The Gibbs energy of formation, enthalpy of formation and heat capacity parameters for solids NaCl(s), NaCl·2H2O(s), Na2SO4(s) and Na2SO4·10H2O(s) are obtained by fitting experimental data on solubilities of NaCl and Na2SO4 in water. The NRTL binary parameters for the (Na+, Cl−)-(Na+, SO42−) pair are regressed from fitting experimental data on dissolution enthalpies and solubilities for the NaCl + Na2SO4 + H2O ternary. 相似文献
1000.