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排序方式: 共有312条查询结果,搜索用时 0 毫秒
1.
Li Quanxin Li Zheng He Cheng Sun Huilin Tan Shengheng Zhang Hua 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(5):2105-2115
Journal of Radioanalytical and Nuclear Chemistry - The simplified 8-oxide system (SiO2-B2O3-Na2O-Al2O3-CaO-TiO2-MoO3-La2O3) has been prepared under two types of cooling methods, and analyzed with... 相似文献
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Zhuliang Zhong Donghui Ma Gaoyuan Zhao Huilin Li Dengyu Xu Dr. Xingang Xie Prof. Dr. Xuegong She 《化学:亚洲杂志》2015,10(12):2599-2603
The first asymmetric total synthesis of kravanhin B has been accomplished with a linear reaction sequence of 13 steps starting from (R)‐(?)‐carvone. The synthesis features an intramolecular aldol cyclization to construct the desired cis‐fused decalin skeleton and an acid‐catalyzed dehydration and olefin isomerization to install the γ‐butenolide ring. 相似文献
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Zhiyu Wang Dr. Xiaoming Wang Zhongwei Chen Dr. Yang Liu Huilin Xie Jie Xue Prof. Lingling Mao Prof. Yanfa Yan Prof. Haipeng Lu 《Angewandte Chemie (International ed. in English)》2023,62(17):e202215206
Introducing chirality into the metal-halide hybrids has enabled many emerging properties including chiroptical activity, spin-dependent transport, and ferroelectricity. However, most of the chiral metal-halide hybrids to date are non-emissive, and the underlying mechanism remains elusive. Here, we show a new strategy to turn on the circularly polarized luminescence (CPL) in chiral metal-halide hybrids. We demonstrate that alloying Sb3+ into chiral indium-chloride hybrids dramatically increases the photoluminescence quantum yield in two new series of chiral indium-antimony chlorides. These materials exhibit strong CPL signals with tunable energy and a high dissymmetry factor up to 1.5×10−2. Mechanistic studies reveal that the emission originates from the self-trapped excitons centered in 5s2 Sb3+. Moreover, near-ultraviolet pumped white light is demonstrated with a polarization up to 6.0 %. Our work demonstrates new strategies towards highly luminescent chiral metal-halide hybrids. 相似文献
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硼石膏近些年在水泥、沥青混合材料等领域应用广泛,其主要成分为CaSO4·2H2O和B2O3以及其他杂质,因此准确、快速测定石膏样品中的硼元素对石膏的应用、资源综合利用等方面具有重要意义。而国家标准GB/T 5484-2012《石膏分析方法》中并没有硼元素的化学分析方法,且相关文献报道也很少。目前测定硼元素主要采用电感耦合等离子体质谱法(ICP-MS),样品前处理多采用酸溶法,而碱熔法应用不多,主要原因是碱熔后溶液中产生大量盐分影响等离子体焰的稳定性,而732型阳离子交换树脂能吸附大量的钠离子,同时吸附了钙、镍、铁及稀土等阳离子,减少盐分干扰。基于此原理,本文采用氢氧化钠碱熔-732型阳离子交换树脂交换分离,在线加入铑内标的方式,建立了ICP-MS法测定石膏中硼的方法,同时由于石膏国家标准物质不包含硼元素的含量,采用高纯硫酸钙分别与岩石标准物质、水系沉积物国家标准物质和土壤国家标准物质混合配置成人工标准物质,并讨论了熔矿体系、阳离子加入量与吸附时间、清洗液、同位素的选择等实验条件。本方法的检出限为0.76μg/g,精密度(RSD,n=7)为0.9%~1.7%,相对误差为1.56%~3.96%,加标回收率在97.5%~102%,该方法快速、准确,记忆效应小,适合石膏中硼元素的测定。 相似文献
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Gold‐Catalyzed 1,2‐Acyloxy Migration/Intramolecular [3+2] 1,3‐Dipolar Cycloaddtion Cascade Reaction: An Efficient Strategy for Syntheses of Medium‐Sized‐Ring Ethers and Amines 下载免费PDF全文
Changgui Zhao Dr. Xingang Xie Shuangshuang Duan Huilin Li Dr. Ran Fang Prof. Dr. Xuegong She 《Angewandte Chemie (International ed. in English)》2014,53(40):10789-10793
A highly efficient strategy for the formation of medium‐sized‐ring ethers and amines based on a gold‐catalyzed cascade reaction, involving enynyl ester isomerization and intramolecular [3+2] cyclization, has been developed. Various multisubstituted medium‐sized‐ring unsaturated ethers and amines were obtained through this transformation. This method represents one of the relatively few transition metal catalyzed intramolecular cycloaddition reactions for medium‐sized ring synthesis. 相似文献
10.
Huilin Hou Xiangkang Zeng Xiwang Zhang 《Angewandte Chemie (International ed. in English)》2020,59(40):17356-17376
Hydrogen peroxide (H2O2) has received increasing attention because it is not only a mild and environmentally friendly oxidant for organic synthesis and environmental remediation but also a promising new liquid fuel. The production of H2O2 by photocatalysis is a sustainable process, since it uses water and oxygen as the source materials and solar light as the energy. Encouraging processes have been developed in the last decade for the photocatalytic production of H2O2. In this Review we summarize research progress in the development of processes for the photocatalytic production of H2O2. After a brief introduction emphasizing the superiorities of the photocatalytic generation of H2O2, the basic principles of establishing an efficient photocatalytic system for generating H2O2 are discussed, highlighting the advanced photocatalysts used. This Review is concluded by a brief summary and outlook for future advances in this emerging research field. 相似文献