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991.
由于E_(Tb~(4 )/Tb~(3 ))~0= 3.1V,使得Tb(Ⅳ)很难以简单离子的形式存在于水(E_(1/2O_2 2H~ )= 1.22V)溶液中。要从水溶液中获得稳定的Tb(Ⅳ),必须降低其平衡电位,通常采用生成难溶盐、配合物或溶胶等方法。 Tb(Ⅳ)化合物最初多以焙烧法制备。Prost在2.5mol/L K_2CO_3-0.5mol/LKOH溶液中用电化学氧化法制得了Tb(Ⅳ)的聚合物,并求得在此条件下E_(Tb~(4 )/Tb~(3 ))= 相似文献
992.
WeiHuaHAN HaoRanLI 《中国化学快报》2005,16(1):15-16
(-)-cis-1, 3-Dibenzyl-hexahydrofuro[3, 4-d]imidazole-2, 4-dione was prepared by a new synthesis method from meso dicarboxylic acid and dehydroabietylamine by asymmetric reduction in good yield with up to 91.6% e.e. value. 相似文献
993.
Xiangrong Chen Xiaobin Ding Zhaohui Zheng Yuxing Peng 《Colloid and polymer science》2005,283(4):452-455
PNIPAAm-b-PPG-b-PNIPAAm triblock copolymers were prepared by redox polymerization. The self-assembly behavior and thermosensitive property of the copolymers in water were studied using 1H-NMR, TEM and a UV spectrophotometer. The results showed that the LCST of the copolymers was 32 °C, which was consistent with that of pure PNIPAAm. The copolymers could form a vesicular structure in an aqueous solution by self-assembly. The hollow structure of the PNIPAAm-b-PPG-b-PNIPAAm vesicles combined with the temperature-sensitive property may enable many potential applications of the vesicles. 相似文献
994.
Reaction of an alkyne‐bridged dicobalt complex, [Co2(CO)6(μ‐Me3SiC=Cpy)] 4 , with bis(diphenylphosphino)methylene (DPPM) or bis(diphenylphosphino)ethylene (DPPE) in THF at 55 °C yielded a DPPM or DPPE doubly bridged dicobalt compound, [{μ‐P,P‐PPh2CH2PPh2}Co2(CO)4(μ‐Me3SiC=Cpy)] 5 or [{μ‐P,P‐PPh2CH2CH2PPh2}Co2(CO)4(μ‐Me3SiC≡Cpy)] 6 . Compound 5 and 6 were characterized by spectroscopic means as well as X‐ray crystal structure determination. 相似文献
995.
催化光度法测定痕量甲醛 总被引:24,自引:2,他引:24
基于磷酸介质中甲醛催化溴酸钾氧化溴甲酚紫的褪色反应 ,建立了测定痕量甲醛的方法。方法的检出限为 1.0× 10 - 5g·L- 1,线性范围为 0 .0 2 0~ 0 .4 8μg·ml- 1,方法简便 ,用于空气中测定痕量甲醛 ,结果满意。 相似文献
997.
998.
The reaction of corresponding cadmium salts with the flexible ligand 1,4-bis(1,2,4-triazol-1-ylmethyl)benzene (bbtz) affords the 3D coordination network [Cd3(bbtz)6(H2O)6](BF4)(6.1.75H2O (1), containing ribbons of rings and planar 2D (4,4) networks polycatenated with each other, the undulating 2D (4,4) network [Cd(bbtz)2(H2O)2](ClO4)2.2H2O (2), and ribbons of rings [Cd(bbtz)2(H2O)2](BF4)2.3DMF (3) and [Cd(bbtz)2(H2O)2](ClO4)2.3DMF (4). 相似文献
999.
Peng Lu Xueli Hu Yujie Li Yazhou Peng Meng Zhang Xue Jiang Youzhou He Min Fu Fan Dong Zhi Zhang 《Journal of Saudi Chemical Society》2019,23(8):1109-1118
A novel CaCO3/graphitic carbon nitride (g-C3N4) photocatalyst was synthesized for the first time via a facile calcination method using CaCO3 and melamine as precursors. The as-prepared samples were characterized using various techniques, such as scanning and transmission electron microscopy, X-ray diffraction, Brunauer-Emmett-Teller analysis, as well as Fourier-transform infrared, X-ray photoelectron, photoluminescence, and UV–vis diffuse reflectance spectroscopy. The results of the experiments confirm the successful coupling of CaCO3 to g-C3N4. The photocatalytic activity of the synthesized CaCO3/g-C3N4 composites was evaluated by assessing their performance in the photocatalytic degradation of crystal violet (CV) in water under visible light irradiation. The analysis shows that CaCO3/g-C3N4 exhibits higher photocatalytic activity towards CV degradation (76.0%) than pristine g-C3N4 (21.6%) and CaCO3 (23.2%). Radical trapping and electron spin resonance experiments show that hydroxyl radicals (OH) and holes (h+) are the key reactive species in the photocatalytic process. The enhanced photocatalytic activity of the composite is mainly attributed to the efficient separation rate of electron-hole pairs achieved through the incorporation of CaCO3. 相似文献
1000.
The crystal structure of the title complex with the stoichiometric formula [Cu(PTA)(Phen)2](p-MBA)(H6O) (Phen=1,10-phenanthroline, PTA=terephthalic acid, p-MBA=p-toluic acid) has been determined by single-crystal X-ray diffraction. The crystal (C48H40CuN4O10, Mr=896.38) belongs to the monoclinic space group C2/c, with the following crystallographic parameters: a=1.778 6(3) nm, b=1.912 5(3) nm, c=1.389 9(2) nm, β=114.686(2)°, V=4.295 7(12) nm3, Dc=1.386 g·cm-3, Z=4, μ(Mo Kα)=0.574 mm-1, F(000)=1 860, final GooF=1.019, R=0.054 0, wR=0.148 3 for 2 644 observed reflections (I>2σ(I)). The crystal structure shows that the copper(Ⅱ) ion is coordinated with two oxygen atoms from one terephthalic acid molecule and four nitrogen atoms from two 1,10-phenanthroline molecules, forming a distorted octahedral coordination geometry. The cyclic voltametric behavior of the complex is also reported. CCDC: 298809. 相似文献