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11.
Literature data on distribution ratios (Dw) of Np(V) and Pa(V) for the AG1-X8 resin are scarce whereas those related on resin capacity factors (k′) values for TEVA, TRU and U/TEVA resins are absent. Therefore, batch extraction experiments for Pa(V) and Np(V) from HCl and HNO3 media were realized, at tracer scale, with AG1-X8 and EIChroM resins (TEVA, TRU and U/TEVA). Based on the new Dw and k′ values obtained in this study, a new protocol for Pa/Np separation has been developed leading to a better separation factor of 105 and a chemical yield of 97 ± 3% and 99 ± 1% for Pa and Np, respectively. A separation of 231Pa from uranium matrix was successfully tested. 相似文献
12.
《Analytical letters》2012,45(12):995-1001
Abstract Correlations between extraction distribution ratios, bond types, and common solvent physical properties were determined for 19 extraction systems. Different types of bonding are involved in the water adduct formation on different types of chelates. 相似文献
13.
Bound rubber formation was investigated in detail by applying various extraction temperatures (at room temperature, 90°C, and 180°C) and novel treatment methods (ammonia bubbling and sonication). Bound rubbers could be divided into three major components of core shell, primary layer including tightly primary layer and occluded rubber, and secondary layer including connecting filament. Bound rubber content of the core shell was measured by four successive procedures of extraction at room temperature, ammonia bubbling, extraction at 180°C and sonication. Bound rubber content of the tightly primary layer was measured by three successive procedures of extraction at 90°C, ammonia bubbling and sonication. Bound rubber content of the primary layer was measured by two successive procedures of extraction at 90°C and sonication. 相似文献
14.
《Analytical letters》2012,45(3):491-505
Abstract Iron (III) was rapidly extracted as its ternary complex with tributyl phosphate and N-phenly1-2-furylacrylohydroxamic acid (PFHA) from weakly acidic (pH 1.0-1.5) solutions into isobutyl methyl ketone and was determined atomic absorption spectrometrically. The method tolerated the presences of a large number of anions and cations commonly associated with iron, and was successfully tested with certified samples of coal fly ash, alloys, and plant tissues. It was also applied to the analysis of animal tissues, natural waters, and wastewaters; validating it by standard addition technique. PFHA was selected from nine new hydroxamic acids. 相似文献
15.
Roberto Lava Emilia Aimo Luciana Menegus Giulio Pojana Antonio Marcomini 《Analytica chimica acta》2013
Two simple analytical methods for the simultaneous determination and quantification of benzotrifluoride and eight chlorinated, amino and nitro benzotrifluoride derivatives in groundwater are proposed. Benzotrifluoride, 4-chlorobenzotrifluoride, 2,4-dichlorobenzotrifluoride and 3,4-dichlorobenzotrifluoride, were extracted by Purge-and-Trap on the basis of their volatile properties, while 3-aminobenzotrifluoride, 4-nitrobenzotrifluoride, 3-amino-4-chlorobenzotrifluoride, 3-nitro-4-chlorobenzotrifluoride and 4-chloro-3,5-dinitrobenzotrifluoride extractions were done with an automated SPE system. The analytical separations and detections were performed with two different GC systems, both equipped with single quadrupole mass spectrometer as detector. The LOD ranges for the two methods were 0.002–0.005 μg L−1 and 0.01–0.07 μg L−1, respectively. Both extraction methods were developed using spiked Milli-Q water and were then demonstrated with groundwater samples collected during autumn 2008. The areas of groundwater collection were polluted due to an episode of improper industrial soil disposal and consequent leakage of aliphatic and aromatic, fluorinated chemicals into the groundwater. This work eventually revealed the presence of several benzotrifluoride compounds most of them, like dichloro- and amino-derivatives, never been reported as environmental contaminants. 相似文献
16.
Luca Nicolotti Chiara CorderoCecilia Cagliero Erica LibertoBarbara Sgorbini Patrizia RubioloCarlo Bicchi 《Analytica chimica acta》2013
The study proposes an investigation strategy that simultaneously provides detailed profiling and quantitative fingerprinting of food volatiles, through a “comprehensive” analytical platform that includes sample preparation by Headspace Solid Phase Microextraction (HS-SPME), separation by two-dimensional comprehensive gas chromatography coupled with mass spectrometry detection (GC × GC–MS) and data processing using advanced fingerprinting approaches. 相似文献
17.
CMPO-离子液体萃取分离铀(VI)体系的电化学性质 总被引:1,自引:0,他引:1
研究了辛基(苯基)-N,N-二异丁基胺甲酰基甲基氧化膦(CMPO)-离子液体(IL)从硝酸铀酰水溶液中萃取铀(VI)的电化学行为, 离子液体(IL)为1-丁基-3-甲基咪唑双三氟甲基磺酰亚胺盐(C4mimNTf2). 用等摩尔系列法测得萃取过程中CMPO与U(VI)形成摩尔比为3:1的配合物. 用循环伏安法研究了萃取液中U(VI)-CMPO配合物的电化学性质, 结果表明, 在C4mimNTf2中U(VI)-CMPO 配合物经过准可逆还原生成U(V)-CMPO 配合物, U(VI)/U(V)电对的表观氧化还原电势(EΘ, vs Fc/Fc+)为(?0.885±0.008) V. 对萃取液进行控制电位电解, 发现在铂片上有沉淀析出. X射线光电子能谱(XPS) 测试结果表明, 沉积物中只含有U(VI)、U(IV)和氧, 而CMPO和C4mimNTf2没有被夹带析出. 相似文献
18.
Maciej Jan Rybicki Anna Klimek-Turek Tadeusz Henryk Dzido 《Molecules (Basel, Switzerland)》2020,25(24)
Coccidiostats are drugs used against coccidiosis, a common disease among breeding animals. Their widespread application leads to the appearance of their residues in food, which is potentially harmful for human health and life. The European Union has established limits of concentrations of these drugs in premixtures and food. Nowadays, there are many methods for monitoring coccidiostats’ presence in market products, but their frequent weakness is sample preparation. Solvent Front Position Extraction is a planar chromatography-based sample preparation method that allows for effective assay of samples with coccidiostats when coupled with LC-MS/MS. The purpose of this research was to find common conditions for the effective isolation of eight coccidiostats from biological sample components with both lower and higher retention than the substances of interest. The acquired results were used for effective isolation of monensin and salinomycin from the premixture samples and allowed for their quantitative determination. The application of a semi-automatic device for the development of chromatograms positively impacted the results, confirming the effectiveness of the method for determining coccidiostats in biological samples. 相似文献
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