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991.
Ammar Mahjoubi Ridha Fethi Mechlouch Belgacem Mahdhaoui Ammar Ben Brahim 《国际自然能源杂志》2013,34(5):210-224
This purpose of this paper is to develop and validate a model to accurately predict the cell temperature of a photovoltaic (PV) module that adapts to various mounting configurations, mounting locations, and climates while only requiring readily available data from the module manufacturer. Results from this model are also compared with results from published cell temperature models. The models were used to predict real-time performance from a PV water pumping systems in the desert of Medenine, south of Tunisia using 60-min intervals of measured performance data during one complete year. Statistical analysis of the predicted results and measured data highlights possible sources of errors and the limitations and/or adequacy of existing models, to describe the temperature and efficiency of PV-cells and consequently, the accuracy of performance of PV water pumping systems’ prediction models. 相似文献
992.
立足资源、面向市场、强化差异性竞争成为中国西部城镇重要发展途径.风景区边缘城镇由于毗邻稀缺的风景名胜资源的区位优势,迫切希望依托风景区带动地方全面发展,事实上却存在开发与保护冲突、景镇建设脱节的现象,其核心矛盾在于景区与城镇定位不明、资源配置不利、产业发展脱节.基于可持续发展理念提出景镇统筹发展思路,其核心包括生态环境保护优先、产业经济统筹发展、空间景观整体塑造、社会生活和谐共荣.最后以重庆统景规划为例,构建以空间、风貌、旅游、地产四大板块为基础的景镇统筹发展整体框架,实现生态安全保障、经济高度发展、三大效益高度统一的发展目标. 相似文献
993.
由于大底盘多塔连体高层建筑特有的结构形式,在外力作用下结构受力性能极其复杂。目前,学术界和工程界在理论分析和试验研究上分析较多的是对大底盘双塔连体结构的研究。而对于三塔及多于三塔的建筑结构的受力性能研究较少。论文采用有限元分析软件ETABS利用振型分解反应谱法,分析了不同连接体参数变化下的大底盘三塔连体高层建筑结构在多遇地震作用下的结构抗震性能规律。通过上述分析结果,总结结构抗震性能规律,为工程设计提供合理的建议。 相似文献
994.
Synthesis and Biopharmaceutical Evaluation of Imatinib Analogues Featuring Unusual Structural Motifs
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Prof. Kyriacos C. Nicolaou Dr. Dionisios Vourloumis Dr. Sotirios Totokotsopoulos Dr. Athanasios Papakyriakou Dr. Holger Karsunky Hanan Fernando Dr. Julia Gavrilyuk Dr. Damien Webb Dr. Antonia F. Stepan 《ChemMedChem》2016,11(1):31-37
A convenient synthesis of imatinib, a potent inhibitor of ABL1 kinase and widely prescribed drug for the treatment of a variety of leukemias, was devised and applied to the construction of a series of novel imatinib analogues featuring a number of non‐aromatic structural motifs in place of the parent molecule's phenyl moiety. These analogues were subsequently evaluated for their biopharmaceutical properties (e.g., ABL1 kinase inhibitory activity, cytotoxicity). The bicyclo[1.1.1]pentane‐ and cubane‐containing analogues were found to possess higher themodynamic solubility, whereas cubane‐ and cyclohexyl‐containing analogues exhibited the highest inhibitory activity against ABL1 kinase and the most potent cytotoxicity values against cancer cell lines K562 and SUP‐B15. Molecular modeling was employed to rationalize the weak activity of the compounds against ABL1 kinase, and it is likely that the observed cytotoxicity of these agents arises through off‐target effects. 相似文献
995.
Development of Simplified Heterocyclic Acetogenin Analogues as Potent and Selective Trypanosoma brucei Inhibitors
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Dr. Gordon J. Florence Andrew L. Fraser Dr. Eoin R. Gould Elizabeth F. King Stefanie K. Menzies Dr. Joanne C. Morris Marie I. Thomson Dr. Lindsay B. Tulloch Marija K. Zacharova Prof. Dr. Terry K. Smith 《ChemMedChem》2016,11(14):1503-1506
Neglected tropical diseases caused by parasitic infections are an ongoing and increasing concern. They are a burden to human and animal health, having the most devastating effect on the world′s poorest countries. Building upon our previously reported triazole analogues, in this study we describe the synthesis and biological testing of other novel heterocyclic acetogenin‐inspired derivatives, namely 3,5‐isoxazoles, furoxans, and furazans. Several of these compounds maintain low‐micromolar levels of inhibition against Trypanosoma brucei, whilst having no observable inhibitory effect on mammalian cells, leading to the possibility of novel lead compounds for selective treatment. 相似文献
996.
Calix[4]arene amide derivatives were employed as new additives within the sol-gel encapsulation of lipase from Candida rugosa (CRL) to improve its catalytic properties. Evaluation of catalytic activity of the encapsulated lipases was acheived by enantioselective hydrolysis of both racemates, Naproxen methyl ester and 2-phenoxypropionic acid methyl ester, in aqueous buffer solution/isooctane reaction system. Results show that enantioselectivity was improved by using calix[4]arene amide derivatives-based encapsulated lipases. The reaction of naproxen methyl ester resulted in 47.6% conversion (x) in 24 h with 88.9% enantiomeric excess of substrate (ees), analogous to an enantioselectivity (E) value of 297 (E = 137 for the encapsulated free enzyme). The conversion of 2-phenoxypropionic acid methyl ester, obtained was 48.4% with E value of 327, enantiomeric excess of substrate (ees) of 92% for the reaction time of 1 h (E = 211 for the encapsulated free enzyme). 相似文献
997.
Bhupander Kumar V. K. Verma Jyoti Tyagi C. S. Sharma A. B. Akolkar 《Polycyclic Aromatic Compounds》2016,36(5):729-744
This study aims to investigate the level of priority polycyclic aromatic hydrocarbons (PAHs) and identification of their potential sources in residential soils. During the study, a total 36 soil samples collected from twelve residential locations at Sahibabad-Ghaziabad area of western Uttar Pradesh, India, a constituted part of the National Capital Region of India. Samples extracted using ultrasonication, cleaned with silica and analyzed by diode array detector–high-performance liquid chromatography using acetonitrile/water as mobile phase. The 25th and 75th percentile concentration of ∑PAHs was 264 μg kg?1 and 584 μg kg?1, respectively, with mean and median of 445 μg kg?1 and 421 μg kg?1. The detection frequency of PAHs in all samples was lower for low molecular weight PAHs (19%) than high molecular weight PAHs (81%). The concentration of seven probable carcinogenic PAHs accounted for 67% of the ∑PAHs. PAHs toxicity potential as benzo(a)pyrene toxicity equivalent ranged between 2.52–253 μg BaPTEQ kg?1. Composition profile of PAHs with different aromatic rings and selected diagnostic molecular ratios suggested the local pyrogenic sources of PAHs from vehicular emissions, diesel engines, biomass combustion, gasoline, and coal combustions. 相似文献
998.
Shahabuddin Memon Ashfaque Ali Bhatti Ümmühan Ocak Miraç Ocak 《Polycyclic Aromatic Compounds》2016,36(4):395-409
This study involves the copper selective chromogenic response of 5, 11, 17, 23-Tetrakis (N-pyrrolidinomethyl)-25, 26, 27, 28-tetrahydroxycalix[4]arene based mannich base (3). Complexation ability of (3) was explored by examining the effect of a series of various metal ions, such as Li+, Na+, K+, Ag+, Ba2+, Ca2+, Mn2+, Mg2+, Sr2+, Ni2+, Cd2+, Co2+, Cu2+, Hg2+, Pb2+, Zn2+, Fe2+, Fe3+, and Al3+, by using UV-visible spectroscopy. Ligand (3) exhibited pronounced selectivity toward Cu2+ even in the presence of various co-existing ions. The stoichiometric analysis, i.e., Job's plot revealed that (3) form 1:1 complex with Cu2+ ion in DMF-H2O system. The complexation phenomenon was confirmed by FT-IR spectroscopy that favors the selective nature of (3) with Cu2+. 相似文献
999.
1000.
苯并(口恶)唑类化合物是一类重要的杂环化合物,不仅在生物、医药等方面有着广泛应用,而且在光学材料、高性能复合材料等诸多领域也显现出独特的性能.以间苯二酚为原料,经过酯化反应和Fries重排、肟化反应、Beckmann重排和水解反应合成4,6-二氨基间苯二酚盐酸盐(DAR· HCl).然后以4,6-二氨基间苯二酚盐酸盐和二硫化碳为原料合成标题化合物,并且优化了过程的工艺条件,过程的总收率为37.3%.利用红外光谱、核磁共振谱、质谱和元素分析等分析手段对中间产物及目标化合物进行了表征. 相似文献