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11.
以邻羟基苯甲醛、邻氨基巯酚、丙二腈为原料合成了有机光致发光材料6-氯甲基-3-(2-苯并噻唑基)-香豆素,将这种新型香豆素与甲基丙烯酸甲酯(MMA)、甲基丙烯酸二甲胺基乙酯(DM)的共聚物(CPA)进行季铵化反应,制得侧基上带有不同配比香豆素的新型发光高分子化合物(C-CPA)。通过差示扫描量热法(DSC)、凝胶色谱法(GPC)、FT-IR和UV-Vis证明了接枝反应是成功的。同时研究发现接枝香豆素的高分子化合物具有很好的荧光性能,这为合成具有优异发光性能的接枝型高分子功能材料提供了一条新的途径。 相似文献
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Andrey S. Erst Alexander A. Chernonosov Natalia V. Petrova Maxim S. Kulikovskiy Svetlana Yu. Maltseva Wei Wang Vera A. Kostikova 《International journal of molecular sciences》2022,23(1)
Aqueous-ethanol extracts (70%) from the leaves of Eranthis longistipitata Regel. (Ranunculaceae Juss.)—collected from natural populations of Kyrgyzstan—were studied by liquid chromatography with high-resolution mass spectrometry (LC-HRMS). There was no variation of the metabolic profiles among plants that were collected from different populations. More than 160 compounds were found in the leaves, of which 72 were identified to the class level and 58 to the individual-compound level. The class of flavonoids proved to be the most widely represented (19 compounds), including six aglycones [quercetin, kaempferol, aromadendrin, 6-methoxytaxifolin, phloretin, and (+)-catechin] and mono- and diglycosides (the other 13 compounds). In the analyzed samples of E. longistipitata, 14 fatty acid–related compounds were identified, but coumarins and furochromones that were found in E. longistipitata were the most interesting result; furochromones khelloside, khellin, visnagin, and cimifugin were found in E. longistipitata for the first time. Coumarins 5,7-dihydroxy-4-methylcoumarin, scoparone, fraxetin, and luvangetin and furochromones methoxsalen, 5-O-methylvisammioside, and visamminol-3′-O-glucoside were detected for the first time in the genus Eranthis Salisb. For all the above compounds, the structural formulas are given. Furthermore, detailed information (with structural formulas) is provided on the diversity of chromones and furochromones in other representatives of Eranthis. The presence of chromones in plants of the genus Eranthis confirms its closeness to the genus Actaea L. because chromones are synthesized by normal physiological processes only in these members of the Ranunculaceae family. 相似文献
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Jih-Jung Chen Chieh-Kai Yang Yueh-Hsiung Kuo Tsong-Long Hwang Wen-Lung Kuo Yun-Ping Lim Ping-Jyun Sung Tsung-Hsien Chang Ming-Jen Cheng 《International journal of molecular sciences》2015,16(5):9719-9731
Three new coumarin derivatives, 8-formylalloxanthoxyletin (1), avicennone (2), and (Z)-avicennone (3), have been isolated from the stem bark of Zanthoxylum avicennae (Z. avicennae), together with 15 known compounds (4–18). The structures of these new compounds were determined through spectroscopic and MS analyses. Compounds 1, 4, 9, 12, and 15 exhibited inhibition (half maximal inhibitory concentration (IC50) values ≤7.65 µg/mL) of superoxide anion generation by human neutrophils in response to formyl-l-methionyl-l-leucyl-l-phenylalanine/cytochalasin B (fMLP/CB). Compounds 1, 2, 4, 8 and 9 inhibited fMLP/CB-induced elastase release with IC50 values ≤8.17 µg/mL. This investigation reveals bioactive isolates (especially 1, 2, 4, 8, 9, 12 and 15) could be further developed as potential candidates for the treatment or prevention of various inflammatory diseases. 相似文献
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柳叶腊梅中总香豆素的提取工艺研究及纯化 总被引:1,自引:0,他引:1
研究畲药柳叶腊梅中总香豆素类化合物的超声辅助提取工艺和液液萃取纯化技术,建立一种简便、快速、廉价、无污染的工艺方法.利用超声的空化作用的液液萃取方法,在单因素实验的基础上,应用正交分析法进行三因素三水平实验研究,最后通过萃取技术得到纯度较高的香豆素类化合物.通过该工艺,利用正交分析的最优条件制备得到提取物中6,7-二甲氧基香豆素(化合物1)和6,7,8-三甲氧基香豆素(化合物2),提取量分别达到0.23 mg/g和0.76mg/g.纯化工艺采用乙醇超声辅助技术和萃取技术,可以快速、方便的提取出目的化合物.该工艺科学合理,适于大规模生产. 相似文献
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采用密度泛函理论(DFT)B3LYP/6-31G方法,对设计的6个不同位置取代氨基的香豆素衍生物的几何构型进行优化。在所得优化结构的基础上对这些分子的稳态二阶NLO系数β值进行计算分析,并采用含时密度泛函理论(TD-DFT)方法计算了其电子性质,研究了取代位置对香豆素类衍生物分子的二阶NLO性质的影响规律。结果表明:当氨基取代在4号位时香豆素分子中的羰基表现出供电性,对分子内电荷转移非常不利,不利于提高分子的β值;当氨基取代在在3、5、6、7、8位时分子中的羰基表现出吸电性,使分子形成D-π-A构型,并且氨基在3、7位的取代能够扩大体系的共轭范围,有效增加了香豆素分子的βtot值。 相似文献
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Synthesis and in vitro Anticancer Activity of Zinc(II) Phthalocyanines Conjugated with Coumarin Derivatives for Dual Photodynamic and Chemotherapy 下载免费PDF全文
Xiao‐Qin Zhou Lu‐Bo Meng Qi Huang Jun Li Ke Zheng Feng‐Ling Zhang Prof. Jian‐Yong Liu Prof. Jin‐Ping Xue 《ChemMedChem》2015,10(2):304-311
The combination of photodynamic therapy and chemotherapy is a promising strategy to overcome growing problems in contemporary medicine, such as low therapeutic efficacy and drug resistance. Four zinc(II) phthalocyanine–coumarin conjugates were synthesized and characterized. In these complexes, zinc(II) phthalocyanine was used as the photosensitizing unit, and a coumarin derivative was selected as the cytostatic moiety; the two components were linked via a tri(ethylene glycol) chain. These conjugates exhibit high photocytotoxicity against HepG2 human hepatocarcinoma cells, with low IC50 values in the range of 0.014–0.044 μM . The high photodynamic activities of these conjugates are in accordance with their low aggregation tendency and high cellular uptake. One of these conjugates exhibits high photocytotoxicity and significantly higher chemocytotoxicity. The results clearly show that the two antitumor components in these conjugates work in a cooperative fashion. As shown by confocal microscopy, the conjugates can localize in the mitochondria and lysosomes, and one of the conjugates can also localize in the cell nuclei. 相似文献
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