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排序方式: 共有2177条查询结果,搜索用时 31 毫秒
861.
862.
863.
IntroductionInhomogcncouscatal}-sis*arccurrentproblcmisthcseparationofthcorganicproductsfromtheactivecatal}'stThcapplicationoft`atersolubletransitionmctalcomplcxcsf0rcataI}ticrcactionshasrcccntl}'attractcdconsidcrablcattcntio.lI~3l.Thcx"atcr-solubleligandsarcslightl}'solublcinorganicmcdia-allot"ingthccatal}'sistobccarricdoutinat\"o-phascs}'stcm.Catal\'strccovcry'isthuscasil}'achievcdb}'dccantationandseparationofthctx"ophascs.Thctris(sodiumm-sulfophcn}-l)-phosphinc,P(m-C6fuS03Na)3(abbr.asTP… 相似文献
864.
制备了7种树脂试剂。采用空气瓶预分解徽量有机物,配合树脂试剂法鉴定氮、硫和卤素。检出限(μg)分别为:NO_3- 0.023,SO_4~(2-)1.2,F-0.03,Cl-2.1,Br-0.05及I~-0.9。并研究了氮的“假检出”问题。 相似文献
865.
The thermal and crystalline behaviour of nano-hydroxyapatite (n-HA) reinforced polyamide 66 (PA66) biocomposites was studied by thermogravimetry (TG) and differential scanning calorimetry (DSC). The thermal properties of PA66 and n-HA/PA66 composites were analysed by TG. The effect of hydroxyapatite on the melting and crystallization of PA66 was evaluated by DSC. DSC measurements exhibited an increase in the crystallization temperature, however, decrease in crystallinity with the addition of n-HA to the PA66 matrix, which was attributed to the hydrogen bonds between the n-HA surface and polyamide 66 molecules. With increase of n-HA content, the melting peak of the PA66 component shifted to higher temperature, suggesting constrained melting. The addition of n-HA to PA66 played the role of nucleating agent and enhanced the crystallization rate. Non-isothermal parameter a measured by Liu method varies from 1.13 to 1.18, from 1.02 to 1.07, and from 1.18 to 1.21 for PA66, 30 wt% n-HA/PA66 and 40 wt% n-HA/PA66, respectively, and the values of K(T) systematically increase with rise in relative degree of crystallinity. 相似文献
866.
Synthesis of graphite nanosheets/AgCl/polypyrrole composites via two-step inverse microemulsion method 总被引:1,自引:0,他引:1
An effective process for the synthesis of graphite nanosheets/AgCl/polypyrrole (NanoGs/AgCl/PPy) composites was developed. NanoGs were prepared by treating the expanded graphite with sonication in aqueous alcohol solution. Then nanocomposites were fabricated via in situ polymerization of pyrrole in the presence of NanoGs and AgCl particles through two-step sequentially inverse microemulsion method. The nanoscale dispersion of NanoGs and AgCl particles was evidenced by the SEM and TEM examinations. From the thermogravimetric analysis, the introduction of inorganic nano-AgCl and NanoGs exhibited a beneficial effect on the thermal stability of pure PPy. According to the four-point-probe test, the conductivity of the final NanoGs/AgCl/PPy composites was dramatically increased compared with pure PPy. 相似文献
867.
Study on the Phase Behavior of Supercritical CO2/Dynol—604/Water System and Solubilization of Methyl Orange in the Microemulsions 总被引:1,自引:0,他引:1
It was found that Dynol-604, a non-fluorous and no silicon-containing nonionic surfactant,was soluble in supercritical (SC) CO2. The phase behavior of SC CO2/Dynol-604/water system was studies. The results showed that one-phase water-in-CO2 microemulsions could be fromed. The solubilization of methyl orange in the microemulsions proved further the existence of water domain in the microemulsions. 相似文献
868.
JinLingCHAI ShouQingWANG GanZuoLI QingXU YanHongGAO 《中国化学快报》2004,15(6):699-702
A novel kinetic mechanism of esterification reaction of 1-hexanoic acid with 1-butanol,catalyzed by lipase, was studied in water-in-oil microemulsions. The microemulsions were formed by alkyl polyglucoside C10G1.54/1-butanol/cyclohexane/phosphate buffer solution. The restult shows that when the ratio of mol concentration of 1-butanol to 1-hexanoic acid is about 3.0,the initial rate V0 get the maximum values. This phenomenon was explained by the modified fishlike phase diagrams. 相似文献
869.
870.
Michael A. Malone Hong Zuo Susan M. Lunte Malcolm R. Smyth 《Journal of chromatography. A》1995,700(1-2):73-80
Capillary electrophoresis with electrochemical detection (CEEC) is evaluated for the determination of tryptophan and kynurenine in microdialysis samples obtained from rat brain. These compounds were separated from all other electroactive metabolites of tryptophan. Limits of detection for both compounds were in the low attomole range. The response was linear for kynurenine between 4.9 and 980 fmol injected with a correlation coefficient of 0.9992 (n = 12). The system was evaluated for monitoring tryptophan and kynurenine in the extracellular fluid of the rat brain following systemic administration of tryptophan. 相似文献