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Dr. Jessica Ceramella Dr. Annaluisa Mariconda Dr. Camillo Rosano Dr. Domenico Iacopetta Dr. Anna Caruso Prof. Pasquale Longo Prof. Maria Stefania Sinicropi Prof. Carmela Saturnino 《ChemMedChem》2020,15(23):2306-2316
Cancer is going to be the first cause of mortality worldwide in the 21th century. It is considered a multifactorial disease that results from the combined influence of many genetic aberrations, leading to abnormal cell proliferation. As microtubules are strongly implicated in cellular growth, they represent an important target for cancer treatment. The well-known microtubule-targeting agents (MTAs) including paclitaxel, colchicine and vinca alkaloids are commonly used in the treatment of various cancers. However, adverse effects and drug resistance are major limitations in their clinical use. To find new candidates able to induce microtubule alteration with reduced toxic effects or drug resistance, we studied a small new series of derivatives that present imidazolinic, guanidinic, thioureidic and hydrazinic groups ( 1 – 9 ). All the compounds were tested for their antitumor activity against a panel of six tumoral cell models. In particular, compound 8 (nonane-1,9-diyl-bis-S-amidinothiourea dihydrobromide) showed the lowest IC50 value against HeLa cells, together with a low cytotoxicity for normal cells. This compound was able to induce the apoptotic mitochondrial pathway and inhibited tubulin polymerization with a similar efficacy to vinblastine and nocodazole. Taken together, these promising biological properties make compound 8 useful for the development of novel therapeutic approaches in cancer treatment. 相似文献
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以15种不同十一烷基咪唑啉衍生物缓蚀剂为研究对象,采用随机森林与多元线性回归相结合考察了分子结构对其缓蚀效率(IE)的影响。首先,从能量、电荷、分子表面与信息量、立体构象与拓扑特征6个方面对15种咪唑啉类缓蚀剂进行了全面表征,共得到55个分子结构参数;然后运用随机森林(RF)与多元线性回归(MLR)分别对特征参数进行了优化,筛选出top10的8个重叠参数。从8个参数中随机挑选3个,使用留一法(LOO)进行多元线性回归模型构建,最终得到了最优的特征组合为分子总能量(Te)、信息含量(Ic)与分子折射率(Mr)。基于此得到的最优定量结构-缓蚀效率关系模型,其相关系数R~2为0.843,关系式表示为IE=-5.517-0.010 1×Te+15.601 7×Ic+0.222×Mr。考察样本后去掉一个奇异样本,其相对误差达到18.9%,剩余14个样本留一法建模,模型效果大大提高,其R~2为0.911。结果表明,Te、Ic、Mr与缓蚀效率具有较高的正相关性,分子结构越稳定、对称性好及折射率高,则其IE值就越高,为设计新型高效的缓蚀剂提供了理论指导。 相似文献
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咪唑啉季铵盐缓蚀剂的合成是将油酸作为原料,利用咪唑啉季铵盐的中间体转化为咪唑啉季铵盐的水溶性液体。一般来说,可以用亚磷酸二甲酯作为中间体,加入催化剂做出水溶性的季铵盐缓蚀液。经过试验与配比,发现合成咪唑啉季铵盐,最佳的工艺温度为90℃,咪唑啉中间体和磷酸二的配比为10:8,溶剂缓蚀效率达到98.3%。 相似文献
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针对油田注水开发过程中存在的腐蚀问题,合成了水溶性的咪唑啉类缓蚀剂LRX,利用静态挂片法和极化曲线法考察了其缓蚀性能。结果表明,在苯甲酸与二乙烯三胺的摩尔比为1∶1.4,咪唑啉中间体与氯乙酸的摩尔比1∶1.5,季铵化温度控制在60℃,反应时间4 h时,合成的咪唑啉类缓蚀剂LRX为阳极型缓蚀剂,对20#钢的缓蚀率达85%;合成的咪唑啉类缓蚀剂LRX与阻垢剂HEDP复配后,在缓蚀和阻CaCO3垢性能方面具有良好的协同效应。 相似文献
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Synthesis,Corrosion Inhibition Performance and Biodegradability of Novel Alkyl Hydroxyethyl Imidazoline Salts 下载免费PDF全文
Hongqin Liu Jun Hu Xiaoze Zhou Dan Liu Baocai Xu Yawen Zhou 《Journal of surfactants and detergents》2015,18(6):1025-1031
New alkyl hydroxyethyl imidazoline salts were synthesized via a high pressure process with imidazoline and dimethyl carbonate, and their chemical structure were confirmed using mass spectral fragmentation and FTIR spectroscopic analysis. In addition, several quaternary ammonium salts with new counterions (formic acid, acetic acid and lactic acid) were also synthesized by ion exchange reaction of methyl carbonate quaternary ammoniums with the corresponding acids. These new compounds reduced the surface tension of water to a minimum value of approximately 27 mN m?1 at a concentration of 8.72 × 10?5 mol L?1. They also show efficient corrosion inhibition performances and could significantly inhibit the corrosion of mild steel in acid solutions. It was also found that the biological degradation of these imidazoline surfactants was greater than 98 % after 7 days. 相似文献