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在DMF/H2O/CH3OH的混合体系中,反应温度为170℃,Mn SO4·4H2O盐溶液在p H=5和7的条件下,加热72小时,最终得到了结构不同的硫酸锰骨架[Mn2(SO4)3]·(H3O)2(1)和[Mn3(SO4)2(OH)2(H2O)2](2)。化合物结构通过单晶X-射线和红外光谱所表征,相应的晶胞参数:化合物1,立方晶系,空间群:P213,a=10.2009(12),V=1061.49(37)3,Goo F=1.158,Flack parameter 0.02(2),R1=0.0186(I2sigma);化合物2,四方晶系,空间群:Pbcm,a=7.3214(15),b=9.984(2),c=13.291(3),V=971.5(4)3,Goo F=1.063,R1=0.0227(I2sigma);单晶X射线分析显示化合物1是一个三维单手性硫酸锰骨架,化合物2是一个非手性羟基硫酸锰骨架。实验结果说明,p H值对硫酸锰骨架的改变起重要作用。 相似文献
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High‐Level Incorporation of Silver in Gold Nanoclusters: Fluorescence Redshift upon Interaction with Hydrogen Peroxide and Fluorescence Enhancement with Herbicide 下载免费PDF全文
Dr. Guijian Guan Dr. Yongqing Cai Dr. Shuhua Liu Dr. Haidong Yu Dr. Shiqiang Bai Dr. Yuan Cheng Dr. Tao Tang Dr. M. S. Bharathi Prof. Yong‐Wei Zhang Prof. Ming‐Yong Han 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(5):1675-1681
High‐level incorporation of Ag in Au nanoclusters (NCs) is conveniently achieved by controlling the concentration of Ag+ in the synthesis of bovine serum albumin (BSA)‐protected Au NCs, and the resulting structure is determined to be bimetallic Ag28Au10‐BSA NCs through a series of characterizations including energy‐dispersive X‐ray spectroscopy, mass spectroscopy, and X‐ray photoelectron spectroscopy, together with density functional theory simulations. Interestingly, the Ag28Au10 NCs exhibit a significant fluorescence redshift rather than quenching upon interaction with hydrogen peroxide, providing a new approach to the detection of hydrogen peroxide through direct comparison of their fluorescence peaks. Furthermore, the Ag28Au10 NCs are also used for the sensitive and selective detection of herbicide through fluorescence enhancement. The detection limit for herbicide (0.1 nm ) is far below the health value established by the U.S. Environmental Protection Agency; such sensitive detection was not achieved by using AuAg NCs with low‐level incorporation of Ag or by using the individual metal NCs. 相似文献
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Temperature memory effect and its stability revealed via differential scanning calorimetry in ethylene‐vinyl acetate within glass transition range 下载免费PDF全文
Tao Xi Wang Wei Min Huang Hongmei Chen Rui Xiao Hai Bo Lu Shu Feng Kang 《Journal of Polymer Science.Polymer Physics》2016,54(17):1731-1737
In this article, we reveal the temperature memory effect (TME) in a commercial thermoplastic polymer, namely ethylene‐vinyl acetate (EVA), within its glass transition range via a series of differential scanning calorimeter (DSC) tests. In addition, we investigate the influence of heating holding time and also compare the observed TME in current study with that of shape memory alloys (SMAs). It is concluded that the TME via DSC (without any macroscopic shape change) is achievable within the glass transition range of a polymer. Conversely, although the observed TME shares the many similar features as those in SMAs, due to the nature of micro‐Brownian motion in the glass transition of polymers, the resulted TME is strongly affected by the heating holding time. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 1731–1737 相似文献
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Daniel J. Tao Dr. Mikko Muuronen Yuriy Slutskyy Alexander Le Prof. Filipp Furche Prof. Larry E. Overman 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(26):8786-8790
The stereochemical outcome of reactions of chiral nucleophilic trisubstituted acetonide radicals with electron‐deficient alkenes is dictated by a delicate balance between destabilizing non‐bonding interactions and stabilizing hydrogen‐bonding between substituents on the α and β carbons. 相似文献
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Sulfur and Nitrogen Codoped Carbon Tubes as Bifunctional Metal‐Free Electrocatalysts for Oxygen Reduction and Hydrogen Evolution in Acidic Media 下载免费PDF全文
Tao Sun Prof. Qiang Wu Yufei Jiang Zhiqi Zhang Lingyu Du Prof. Lijun Yang Prof. Xizhang Wang Prof. Zheng Hu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(30):10261-10261
Invited for the cover of this issue is the group of Qiang Wu and Zheng Hu at Nanjing University. The image depicts sulfur and nitrogen codoped carbon tubes as bifunctional metal‐free electrocatalysts for oxygen reduction and hydrogen evolution in acidic media. Read the full text of the article at 10.1002/chem.201601535 . 相似文献
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