分类: 化学 >> 核化学 提交时间: 2023-06-13
摘要: Objective: We herein fabricated a branched structure containing AO groups on polypropylene/polyethylene spun-laced nonwoven (PP/PE SNW) fibers using grafting polymerization induced by radiation (RIGP) to improve AO utilization. Methods: The chemical structures, thermal properties, and surface morphologies of the raw and treated PP/PE SNW fibers were studied. The adsorption properties were investigated using batch adsorption experiments in simulated seawater with an initial uranium concentration of 500 gL-1 (pH 4, 25℃). Results: The maximum adsorption capacity of the adsorbent material was 137.3 mgg-1 within 24 h; moreover, the uranyl removal reached 96% within 240 min. Limitations: Only simulated seawater adsorption experiments have been conducted, and real seawater adsorption experiments are yet to be conducted. Conclusions: The adsorbent had an AO utilization rate of 1/3.5 and was stable over a pH range of 410, with good selectivity and reusability, demonstrating its potential for seawater uranium extraction.
分类: 生物学 >> 病毒学 提交时间: 2020-03-06
摘要: 冠状病毒SARS-CoV,MERS-CoV和新发现的2019-nCoV所引发的传染性疾病严重威胁着人类的生命健康安全。位于冠状病毒表面的spike(S)糖蛋白在病毒传播及感染过程中负责结合宿主细胞受体,融合细胞中的膜结构等关键步骤,是病毒重要的药物靶点。其中在冠状病毒中高度保守的S2亚基作为融膜机器,介导了病毒与宿主之间的膜融合过程。我们运用冷冻电镜单颗粒三维重构技术解析了SARS-CoV S糖蛋白的融膜后构象的结构,展示了S2亚基在融膜过程中的结构特点和构象变化。结合保守性比对和糖基化修饰指认,这项工作分析了位于S2亚基的潜在药物靶点,有益于相关疫苗和药物的开发和设计。