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排序方式: 共有321条查询结果,搜索用时 31 毫秒
101.
Dominic C. Castell Varvara I. Nikolayenko Debobroto Sensharma Kyriaki Koupepidou Katherine A. Forrest Carlos J. Solanilla-Salinas Brian Space Leonard J. Barbour Michael J. Zaworotko 《Angewandte Chemie (International ed. in English)》2023,62(19):e202219039
An emerging strategy in the design of efficient gas storage technologies is the development of stimuli-responsive physisorbents which undergo transformations in response to a particular stimulus, such as pressure, heat or light. Herein, we report two isostructural light modulated adsorbents (LMAs) containing bis-3-thienylcyclopentene (BTCP), LMA-1 [Cd(BTCP)(DPT)2] (DPT=2,5-diphenylbenzene-1,4-dicarboxylate) and LMA-2 [Cd(BTCP)(FDPT)2] (FDPT=5-fluoro-2,diphenylbenzene-1,4-dicarboxylate). Both LMAs undergo pressure induced switching transformations from non-porous to porous via adsorption of N2, CO2 and C2H2. LMA-1 exhibited multi-step adsorption while LMA-2 showed a single-step adsorption isotherm. The light responsive nature of the BTPC ligand in both frameworks was exploited with irradiation of LMA-1 resulting in a 55 % maximum reduction of CO2 uptake at 298 K. This study reports the first example of a switching sorbent (closed to open) that can be further modulated by light. 相似文献
102.
Dr. Zhong Wang Hannah R. Felstead Robert I. Troup Prof. Bruno Linclau Dr. Philip T. F. Williamson 《Angewandte Chemie (International ed. in English)》2023,62(21):e202301077
Bioactive compounds generally need to cross membranes to arrive at their site of action. The octanol-water partition coefficient (lipophilicity, logPOW) has proven to be an excellent proxy for membrane permeability. In modern drug discovery, logPOW and bioactivity are optimized simultaneously, for which fluorination is one of the relevant strategies. The question arises as to which extent the often subtle logP modifications resulting from different aliphatic fluorine-motif introductions also lead to concomitant membrane permeability changes, given the difference in molecular environment between octanol and (anisotropic) membranes. It was found that for a given compound class, there is excellent correlation between logPOW values with the corresponding membrane molar partitioning coefficients (logKp); a study enabled by novel solid-state 19F NMR MAS methodology using lipid vesicles. Our results show that the factors that cause modulation of octanol-water partition coefficients similarly affect membrane permeability. 相似文献
103.
建立了一种磁性分散固相萃取气相色谱法快速测定地表水中硝基苯类化合物的分析方法,并优化了磁性萃取材料的用量、萃取的时间、解吸溶剂的选择、盐效应等试验影响因素.试验结果表明,硝基苯类化合物的检出限为0.000 4~0.007 mg/L,回收率为84.0%~97.6%,相对标准偏差为3.4%~5.3%.方法具有适用性广、溶剂用量少和操作简便等特点,能很好的测定地表水中的硝基苯类化合物. 相似文献
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105.
Identification and quantitation of major phenolic compounds from penthorum chinense pursh. by HPLC with tandem mass spectrometry and HPLC with diode array detection
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Weiwei Guo Xiaoqing Chen Ping Yu Meng Wang Xia Wu Dayong Zhang 《Journal of separation science》2015,38(16):2789-2796
Penthorum chinense Pursh. is a traditional Chinese herbal medicine used for the treatment of various ailments specially related to liver. Gansu Granule, the medicine made from the extract of P. chinense, has been widely used in the clinical setting. But the information about its active ingredients is lacking. In this paper, the extract of P. chinense was analyzed by high performance liquid chromatography with electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry. Among the 27 compounds that were identified based on their mass spectrometry data, ten were reported for the first time from P. chinense. Chromatographic fingerprints generated by high‐performance liquid chromatography by analyzing 21 batches of P. chinense, displayed six common peaks. Finally, four major compounds were identified namely; gallic acid, brevifolin carboxylic acid, 2,6‐dihydroxyacetophenone‐4‐O‐β‐d‐ glucoside, and pinocembrin‐7‐O‐β‐d‐ glucoside. The average content of each compound was 24.58, 109.6, 15.52, and 18.81 mg/g, respectively. In addition, this study also suggests that the qualitative liquid chromatography with mass spectrometry and the quantitative high‐performance liquid chromatography analytical methods using monolithic columns are simple, rapid, accurate, and reproducible and have the potential to be used for the comprehensive quality control of P. chinense. 相似文献
106.
The new names are listed for several types of common inorganic compounds such as allotropes, homopolyatomic cations, homopolyatomic anions, heteropolyatomic anions and oxyacids, based on "NOMENCLATURE OF INORGANIC CHEMISTRY – IUPAC Recommendations 2005". The characteristics of the new nomenclature have been analyzed and summarized, with emphasize on the introduction of the additive nomenclature. 相似文献
107.
采用小型释放舱-热脱附-气相色谱-质谱联用技术测定了电子电气产品中8种挥发性有机化合物(苯、甲苯、邻二甲苯、间二甲苯、对二甲苯、乙苯、乙酸丁酯和苯乙烯)的释放量.对一级脱附参数(一级脱附温度、一级脱附流量、一级脱附时间)、冷阱温度、捕集管脱附温度、脱附时间条件进行了优化,并进行了线性关系、回收率、精密度等试验.结果表明:本方法可用于测定电子电气产品中释放的8种常见的挥发性有机化合物的释放量,线性范围10-1000ng,当采样量为6L时,定量限为1.7μg/m3,回收率范围在89.5%-106%之间,相对标准偏差小于7%. 相似文献
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110.
在南方某癌症高发县5个乡镇10个村进行布点取样,采集深层地下水与浅层地下水共计20个水样。采用吹扫捕集与气相色谱-质谱联用方法测定水样中13种挥发性有机物(VOCs),检出二氯甲烷、三氯甲烷、苯和四氯化碳4种VOCs,其浓度分别为0.36—13.52、0.41—18.71、0.57—11.75μg/L和1.56—214.62μg/L。1个水样中苯和16个水样中四氯化碳超过GB 5749-2006规定的限值。采用优化的USEPA风险评价模型,对VOCs进行人体健康风险评价,其非致癌风险指数0.0073—0.7100,致癌风险水平1.98×10-6—1.99×10-4,全部水样的致癌风险水平超过10-6水质监控值,1个水样的致癌风险水平超过10-4的可接受水平。四氯化碳对非致癌风险指数和致癌风险水平贡献最大。 相似文献