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991.
992.
Junpeng Xiong Weili Shao Ling Wang Chen Cui Yurui Jin Hongqin Yu Pengju Han Yanfei Gao Fan Liu Qingqing Ni Jianxin He 《大分子材料与工程》2021,306(11):2100371
Recently, because of the outbreak of COVID-19, the demand for various types of filter elements in protective materials has increased globally. Furthermore, new requirements for the filtration performance of PM2.5 liquid (oil) particles have been put forward. In this work, Superhydrophobic and superoleophobic composite nanofibers with excellent filtration capacity for oil and salt particles are developed through the modification of polyacrylonitrile (PAN) by fluoro-polyurethane (FPU) doping. The results show that the PAN/FPU composite nanofibers doped with 9 wt% FPU has a uniform fiber morphology with a diameter of 240 ± 30 nm. Compared to the pure PAN nanofibers, the water-based contact angle of PAN/FPU increases from 90 ± 5° to 151 ± 5°, and the oil-based contact angle increases from 58 ± 2° to 152 ± 3°. Importantly, at a high flow rate of 95 L min−1, the filtration efficiency of the PAN/FPU nanofiber membrane for 0.3 µm oil particles increases from 92 ± 1% to 99.2 ± 0.1%. After cyclic loading, the filtration efficiency of 0.3 µm oil particles remains above 98%. Meanwhile, the filtration efficiency for 0.3 µm salt particles remains at 98.23 ± 0.1%. The PAN/FPU nanofiber membrane developed in this work is effective in applications and has good market prospects as a protective filtration material. 相似文献
993.
Dr. Xicheng Liu Mingxiao Shao Congcong Liang Jinghang Guo Guangxuan Wang Xiang-Ai Yuan Zhihong Jing Laijin Tian Prof. Dr. Zhe Liu 《Chembiochem : a European journal of chemical biology》2021,22(3):557-564
A series of half-sandwich structural iridium(III) phenanthroline (Phen) complexes with halide ions (Cl−, Br−, I−) and pyridine leaving groups ([(η5-CpX)Ir(Phen)Z](PF6)n, Cpx: electron-rich cyclopentadienyl group, Z: leaving group) have been prepared. Target complexes, especially the Cpxbiph (biphenyl-substituted cyclopentadienyl)-based one, showed favourable anticancer activity against human lung cancer (A549) cells; the best one ( Ir8 ) was almost five times that of cisplatin under the same conditions. Compared with complexes involving halide ion leaving groups, the pyridine-based one did not display hydrolysis but effectively caused lysosomal damage, leading to accumulation in the cytosol, inducing an increase in the level of intracellular reactive oxygen species and apoptosis; this indicated an anticancer mechanism of oxidation. Additionally, these complexes could bind to serum albumin through a static quenching mechanism. The data highlight the potential value of half-sandwich iridium(III) phenanthroline complexes as anticancer drugs. 相似文献
994.
讨论带有多个反凸约束的线性规划。这类问题由于其内在困难性（可行域一般为非凸不连通集）而难以求解．提出了一个切平面算法，并对Ｈｉｌｌｅｓｔａｄ的例子执行了算法。 相似文献
995.
996.
997.
本文介绍了一个微机上运行的注塑模ＣＡＤ系统，此系统主要解决了四个难点，浇注系统设计，冷却系统分析，型腔，型芯的曲面造型设计，装配图和零件工作图的设计绘制，经厂家实际运用证明，该系统使用方便，结果正确，能提高设计效率，降低生产成本。 相似文献
998.
介绍了萃取精馏技术在HFC-32、HFC-134a、HFC-152a、HFC-125、HFC-245fa等ODS替代品纯化中的应用进展。 相似文献
999.
根据啤酒废水的特点,考察了采用膜生物反应器(MBR)技术深度处理啤酒废水过程中的水质指标与设备运行参数,并对污泥浓度进行测定,从而对污泥负荷以及膜污染状况进行研究,工程运行结果表明:在进水CODCr642～1626mg/L、NH4+-N15～35mg/L、TP0.6～14mg/L、TN19.5～41.1mg/L情况下,MBR产水CODCr50mg/L、NH4+-N5mg/L、TP0.3mg/L、TN2.3mg/L。水质达到国家景观用水标准(GB/T18921—2002);好氧池DO控制在2～4mg/L,可有效提高氨氮的去除率;适当调整排泥量,使膜池污泥质量浓度维持在6～8g/L可缓解膜污染速度。 相似文献
1000.
A functional gelable triblock copolymer, poly(2-vinylpyridine)-block-poly(3-(triethoxysilyl)propyl methacrylate)-block-polystyrene (P2VP-b-PTEPM-b-PS), was prepared by the combination of reversible addition-fragmentation chain transfer (RAFT) mediated radical polymerization and copper catalyzed click chemistry. Bulk microphase separation of P2VP310-b-PTEPM58-b-PS322 under different conditions was studied in order to prepare organic/inorganic nanoobjects by a procedure of crosslinking PTEPM phases and dispersing in a solvent. The conditions included using different annealing solvents and adding stearic acids to form supramolecular complexes with P2VP blocks respectively. Then the packed cylinders with P2VP cores and PTEPM shells dispersed in the PS matrix, lamella with alternating PS, PTEPM and P2VP layers, and the inverse cylindrical morphology with PS cores and PTEPM shells dispersed in the matrix of P2VP/stearic acid complex were obtained respectively just from the same triblock copolymer sample. After crosslinking PTEPM microdomains by sol-gel process and dispersing in solvents, a series of organic/inorganic polymeric nanoobjects, including two types of nanofibers with inverse internal structure and one novel kind of nanoplates, were produced. Further modification of the fibers with P2VP cores has been studied. 相似文献