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排序方式: 共有890条查询结果,搜索用时 15 毫秒
1.
Aidaoui Lakhdar Lasbet Yahia Selimefendigil Fatih 《Journal of Thermal Analysis and Calorimetry》2022,147(10):5865-5882
Journal of Thermal Analysis and Calorimetry - This work aims to characterize the heat exchange system efficiency and entropy generation of nanofluid forced convection flow with chaotic... 相似文献
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Gulsah Saydan Kanberoglu Erkan Yilmaz Mustafa Soylak 《Journal of the Iranian Chemical Society》2018,15(10):2307-2314
In this study, we used deep eutectic solvents for digestion and ultrasound-assisted emulsification liquid phase microextraction (UA-ELPME) of copper in liver samples. Different types of DESs were prepared for digestion and microextraction steps. DESs consisting of lactic acid and choline chloride for the digestion step and DESs consisting of tetrabuthylamonium chloride and decanoic acid for ultrasound-assisted emulsification liquid phase microextraction were used in this method. The liver samples were digested by using DES-based digestion method. After digestion step, Cu(II) ions in aqueous phase were complexed with sodium dimethyl dithiocarbamate (NaDMDTC) and the obtained hydrophobic complex was extracted to tetrabuthylamonium chloride-decanoic acid DES phase. A microsample injection system coupled with flame atomic absorption spectrometer (MS-FAAS) was used in the detection of copper. LOD, LOQ, PF and % RSD were determined as 4.00, 13.2 µg L??1, 10 and 3.2%, respectively. The proposed microextraction procedure was successfully applied to copper contents of the liver samples. 相似文献
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It is shown that for , there exists an optimal packing with triples on points that contains no Pasch configurations. Furthermore, for all (mod 6), there exists a pairwise balanced design of order , whose blocks are all triples apart from a single quintuple, and that has no Pasch configurations amongst its triples. 相似文献
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Deringoz Fatih Guliyev Vagif S. Nakai Eiichi Sawano Yoshihiro Shi Minglei 《Positivity》2019,23(3):727-757
Positivity - In the present paper, we will characterize the boundedness of the generalized fractional integral operators $$I_{\rho }$$ and the generalized fractional maximal operators $$M_{\rho }$$... 相似文献
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Topcuoglu Bulent Ozmen Suleyman Fatih Boztosun Ismail Gulludag Cevdet Bertan 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(2):783-797
Journal of Radioanalytical and Nuclear Chemistry - In this study, natural (226Ra, 232Th, 40K) and artificial (137Cs) radionuclide activity concentration levels of 63 greenhouse soils collected from... 相似文献
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Journal of Thermal Analysis and Calorimetry - Aminosilane-modified MCM-41 and SBA-15 mesoporous silicas were synthesized using sodium silicate extracted from gold mine tailings slurry in this... 相似文献
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In this study, it was aimed to investigate the chemical composition and antioxidant activities of two Euphorbia species. The major component of the fatty acid compositions obtained from the petroleum ether extracts was identified as palmitic acid for Euphorbia gaillardotii and Euphorbia macroclada. The main constituents of the essential oils were identified as arachidic acid for E. gaillardotii and tetratetracontane for E. macroclada. Among the 27 studied compounds, hesperidin, rutin, hyperoside and quinic, malic, gallic and tannic acids were found to be the most abundant compounds in the two Euphorbia species. The methanol extracts of E. gaillardotii and E. macroclada showed strong antioxidant activity in all tested methods. Particularly, IC50 values of E. macroclada methanol extract that was the richest in terms of total phenolic-flavonoid contents were found to be lower than α-tocopherol and butylated hydroxytoluene in β-carotene bleaching, 2,2-diphenyl-1-picrylhydrazyl free and ABTS cation radical scavenging methods. 相似文献