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71.
Crystallography Reports - A di-nuclear uranyl complex with the formula of [(UO2)2(L)4(H2O)2]?4H2O (1) (HL = quinoline-6-carboxylic acid) was synthesized hydrothermally and characterized by... 相似文献
72.
Birui Shi Yan Zhang Baolin Huang Huiping Lin Qiong Zhou Yujue Wang Zheng Cai Menghua Liu 《Molecules (Basel, Switzerland)》2022,27(3)
With the widespread clinical use of drug combinations, the incidence of drug–drug interactions (DDI) has significantly increased, accompanied by a variety of adverse reactions. Drug transporters play an important role in the development of DDI by affecting the elimination process of drugs in vivo, especially in the pathological state. Tubulointerstitial fibrosis (TIF) is an inevitable pathway in the progression of chronic kidney disease (CKD) to end-stage renal disease. Here, the dynamic expression changes of eleven drug transporters in TIF kidney have been systematically investigated. Among them, the mRNA expressions of Oat1, Oat2, Oct1, Oct2, Oatp4C1 and Mate1 were down-regulated, while Oat3, Mrp2, Mrp4, Mdr1-α, Bcrp were up-regulated. Pearson correlation analysis was used to analyze the correlation between transporters and Creatinine (Cr), OCT2 and MATE1 showed a strong negative correlation with Cr. In contrast, Mdr1-α exhibited a strong positive correlation with Cr. In addition, the pharmacokinetics of cimetidine, ganciclovir, and digoxin, which were the classical substrates for OCT2, MATE1 and P-glycoprotein (P-gp), respectively, have been studied. These results reveal that changes in serum creatinine can indicate changes in drug transporters in the kidney, and thus affect the pharmacokinetics of its substrates, providing useful information for clinical use. 相似文献
73.
Transport in Porous Media - During waterflooding, spontaneous imbibition is a fundamental recovery mechanism in fractured reservoirs. A large number of numerical and experimental studies have been... 相似文献
74.
针对目前多档输电线动力特性研究中存在的不足,将任意一档导线视为子结构并基于现有的索振动理论获得了其动张力;利用相邻两档导线的动张力建立了悬垂绝缘子串绕其悬挂点摆动的动力学方程;综合每一档导线的振动方程以及悬垂绝缘子串的摆动方程建立了两档及三档输电线的动力学方程,求解得到由端部位移激励产生的动刚度;通过对动刚度进行分析得到了多档输电线的固有频率以及模态的理论表达形式;建立了小高差的两档及三档导线的有限元模型,理论分析结果与有限元结果一致,验证了理论公式的正确性。本文提出的动刚度理论对于研究多档输电线的动态响应具有重要的应用价值。 相似文献
75.
76.
Shangwang Liu Tongbo Cai Xiufang Tang Yangyang Zhang Changgeng Wang 《Entropy (Basel, Switzerland)》2022,24(1)
Aiming at recognizing small proportion, blurred and complex traffic sign in natural scenes, a traffic sign detection method based on RetinaNet-NeXt is proposed. First, to ensure the quality of dataset, the data were cleaned and enhanced to denoise. Secondly, a novel backbone network ResNeXt was employed to improve the detection accuracy and effection of RetinaNet. Finally, transfer learning and group normalization were adopted to accelerate our network training. Experimental results show that the precision, recall and mAP of our method, compared with the original RetinaNet, are improved by 9.08%, 9.09% and 7.32%, respectively. Our method can be effectively applied to traffic sign detection. 相似文献
77.
Nickel (Ni)-lignin nanocomposites were synthesized from nickel nitrate and kraft lignin then catalytically graphitized to few-layer graphene-encapsulated nickel nanoparticles (Ni@G). Ni@G nanoparticles were used for catalytic decomposition of methane (CDM) to produce COx-free hydrogen and graphene nanoplatelets. Ni@G showed high catalytic activity for methane decomposition at temperatures of 800 to 900 °C and exhibited long-term stability of 600 min time-on-stream (TOS) without apparent deactivation. The catalytic stability may be attributed to the nickel dispersion in the Ni@G sample. During the CDM reaction process, graphene shells over Ni@G nanoparticles were cracked and peeled off the nickel cores at high temperature. Both the exposed nickel nanoparticles and the cracked graphene shells may participate the CDM reaction, making Ni@G samples highly active for CDM reaction. The vacancy defects and edges in the cracked graphene shells serve as the active sites for methane decomposition. The edges are continuously regenerated by methane molecules through CDM reaction. 相似文献
78.
Transport in Porous Media - In a recent numerical study, it was demonstrated that characterizing reservoir permeability in terms of rock’s quality, as observed in lab and field, is the most... 相似文献
79.
Leyu Xin Limin Guo Salamet Edirs Zepeng Zhang Chenyang Cai Yongxing Yang Yali Lian Haiyan Yang 《Molecules (Basel, Switzerland)》2022,27(7)
Safflower seed oil (SSO) is considered to be an excellent edible oil since it contains abundant essential unsaturated fatty acids and lipid concomitants. However, the traditional alkali-refined deacidification process of SSO results in a serious loss of bioactive components of the oil and also yields massive amounts of wastewater. In this study, SSO was first extracted by ultrasonic-assisted ethanol extraction (UAEE), and the extraction process was optimized using random centroid optimization. By exploring the effects of ethanol concentration, solid–liquid ratio, ultrasonic time, and the number of deacidification times, the optimum conditions for the deacidification of safflower seed oil were obtained as follows: ethanol concentration 100%, solid–liquid ratio 1:4, ultrasonic time 29 min, and number of deacidification cycles (×2). The deacidification rate was 97.13% ± 0.70%, better than alkali-refining (72.16% ± 0.13%). The values of acid, peroxide, anisidine and total oxidation of UAEE-deacidified SSO were significantly lower than those of alkali-deacidified SSO (p < 0.05). The contents of the main lipid concomitants such as tocopherols, polyphenols, and phytosterols in UAEE-decidified SSO were significantly higher than those of the latter (p < 0.05). For instance, the DPPH radical scavenging capacity of UAEE-processed SSO was significantly higher than that of alkali refining (p < 0.05). The Pearson bivariate correlation analysis before and after the deacidification process demonstrated that the three main lipid concomitants in SSO were negatively correlated with the index of peroxide, anisidine, and total oxidation values. The purpose of this study was to provide an alternative method for the deacidification of SSO that can effectively remove free fatty acids while maintaining the nutritional characteristics, physicochemical properties, and antioxidant capacity of SSO. 相似文献
80.
A biochemometrics strategy combining quantitative determination, bioactivity evaluation, and relationship analysis was proposed for identification of analgesic components of herbs. First, a robust liquid chromatography tandem mass spectrometry method was developed for simultaneous determination of nine major alkaloids in crude and vinegar‐processed Corydalis turtschaninovii. Nine alkaloids were separated on a BEH C18 column with a mobile phase consisting of acetonitrile and water spiked with 0.1% formic acid and then detected by multiple reactions monitoring in the positive ion mode. Nitidine chloride was employed as the internal standard. The method displayed good linearity and the precisions of intra‐day and inter‐day were all within 3.0%. The recovery rates of each alkaloid ranged from 97.1 to 102.9%. The method was successfully applied for quantitative analysis of nine alkaloids in ten batches of crude and vinegar‐processed Corydalis turtschaninovii. Second, the analgesic effects of crude and vinegar‐processed Corydalis turtschaninovii were evaluated in mice. Third, principle component analysis, canonical correlation analysis, and partial least squares regression were used to analysis the relationship between the contents of nine major alkaloids and the analgesic effect of different crude and vinegar‐processed samples. Tetrahydropalmatine, coptisine, and dehydrocorydaline have a close positive correlation with the analgesic effect. 相似文献