Results 21 to 30 of about 12,003 (193)
Rare Metals, EarlyView.ABSTRACT Ni3S2 has emerged as a promising catalyst for the electrochemical oxidation of biomass‐derived 5‐hydroxymethylfurfural (HMF) to 2,5‐furandicarboxylic acid (FDCA), driven by its distinctive physicochemical properties. However, its practical catalytic efficiency is severely hindered by abundant electrochemically inactive surface sites and poor ...
Cheng‐Feng Yi +5 more
wiley +1 more source
Rare Metals, EarlyView.ABSTRACT Chlorination roasting has emerged as a promising pyrometallurgical strategy for the selective recovery of lithium from spent lithium‐ion batteries (LIBs). In this study, a natural roasting agent, seawater‐derived chlorides, was employed to selectively extract lithium from spent LiNi0.5Co0.2Mn0.3O2 (NCM523) cathode. MgCl2·6H2O, a main component
Bei‐Lei Zhang +7 more
wiley +1 more source
Rare Metals, EarlyView.ABSTRACT This study developed a FeSiAl@LMPGP composite material to address the demand for low‐frequency electromagnetic absorption. Through controllable heat treatment, FeSiAl particles and PbO nanoparticles self‐assembled into a high‐density Mott–Schottky heterointerface structure, which exhibited a significant built‐in electric field (BIEF) effect ...
Yuqi Wang +5 more
wiley +1 more source
CRISPR-Cas9 System-based Gene Editing in the Escherichia coli Genome and Bacterial Drug-resistant Reversal [PDF]
, 2017 抗生素的发现是人类对抗病原菌感染的重大里程碑，但是传统抗生素是通过阻断细菌中共有的信号通路或新陈代谢途径来起作用的，往往无法区分杀菌对象，长期使用会导致菌群失调及耐药性的产生，因此我们需要找出一种新型抗菌药物能特异针对病原菌或耐药菌。CRISPR-Cas9系统来源于细菌的获得性免疫，能够利用RNA与Cas相关蛋白识别特异DNA序列并对其进行切割。与传统基因编辑工具如锌指核酸内切酶(ZFNs)和类转录激活因子(TALENs)相比具有简单，高效的优点 ...
姚文晔
core
Rare Metals, EarlyView.ABSTRACT The development of high‐performance electromagnetic protection materials integrating broadband absorption and effective shielding capabilities is hindered by challenges in simultaneously optimizing multiple electromagnetic properties through conventional material designs.
Changlong Du +9 more
wiley +1 more source
Preparation of Lead-free Composite Powder Solder Paste and Study on Reliability of Lead-free Solder Joint [PDF]
, 2012 由于大量含铅焊料废弃物对人类健康以及环境的危害日趋严重，大部分国家已相应立法禁止使用含铅焊料，并积极推进电子封装无铅化进程，其中开发新型无铅焊料显得颇为重要。另外随着封装密度的不断提高，热老化和电迁移现象已经严重影响电子封装的可靠性。以新型无铅焊料的开发以及焊料焊点的可靠性研究为切入点，本论文首先对本实验室自行设计并制备的Sn-Bi-Cu系中低温用复合粉体材料进行表征，并制出与其相匹配的助焊剂，从而开发出具有广泛应用前景的电子封装用复合粉焊膏；然后对Sn-0.7Cu、Sn-3.0Ag-0 ...
王建
core
Rare Metals, EarlyView.ABSTRACT The polyanionic compound Na3V2(PO4)3 (NVP) has emerged as a competitive cathode material for sodium‐ion batteries (SIBs), owing to its high‐voltage redox activity (3.4 V vs. the Na+/Na reference couple) and NASICON‐type framework that enables superior ionic conductivity.
Xiaolei Wu +5 more
wiley +1 more source
Gaoya dianqi, 2019 文中针对介质阻挡放电呈现的极性效应,研究了基于放电李萨如图的方法,提出以极性效应参数k来定量表征极性效应的强弱。在高频和工频两种条件下对不同网格密度的丝网电极和平板电极进行了实验研究,结果表明单介质的丝网电极k值较大,双介质的平板电极k值较小;随着频率和电压的升高,k值减小,极性效应减弱。上述结果表明参数k值能够有效用于极性效应的研究。
李兴旺, 叶齐政
doaj
Design of a Fluoride-Selective Colorimetric Receptor and Its Fluoride Recognition Mechan [PDF]
, 2004 ［中文文摘］将酰胺识别基团耦合至基态具有分子内电荷转移特征的对硝基苯基偶氮苯胺分子中 ,设计合成了受体分子N 苯甲酰基 4 ( 4′ 硝基苯基偶氮基 )苯胺 ( 3 ) ,对氟离子表现出极高的识别选择性 .乙腈中该受体 3的最大吸收峰位于 3 80nm ,加入氟离子后 ,该吸收峰强度逐渐减弱 ,同时在 5 3 0nm处出现新的吸收峰 ,后者为受体分子与氟离子形成的 1∶1配合物的吸收峰 .溶剂极性效应实验表明 ,该吸收峰具有电荷转移特征 .引入氟离子后受体 3溶液的颜色由浅黄色转变为紫红色 ...
张煊, 江云宝, 郭琳
core
教育研究, 2019 PBL教学指的是将学习放在复杂、有意义的问题情境中,学生以小组合作形式进行讨论有效地解决其中的问题,这样学生就能够学习到更多科学知识,提升学生的解决问题能力、自主学习能力[1]。因此,在医学教学过程中,教师需要引进PBL教学模式,提升学生的学习积极性和实践能力。基于此,文章阐述了PBL教学的相关内容,并对PBL教学在临床医学教育中的应用进行了研究。
金桥 王
semanticscholar +1 more source