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《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(31):9264-9268
Control over the solubility properties of container molecules is a central challenge in host–guest chemistry. Herein we present a simple anion‐exchange protocol that allows the dissolution in water of various hydrophobic metal–organic container molecules prepared by iron(II)‐templated subcomponent self‐assembly. Our process involved the exchange of less hydrophilic trifluoromethanesulfonate anions for hydrophilic sulfate; the resulting water‐soluble cages could be rendered water‐insoluble through reverse anion exchange. Notably, this strategy allowed cargoes within capsules, including polycyclic aromatic compounds and complex organic drugs, to be brought into water. Hydrophobic effects appeared to enhance binding, as many of these cargoes were not bound in non‐aqueous media. Studies of the scope of this method revealed that cages containing tetratopic and tritopic ligands were more stable in water, whereas cages with ditopic ligands disassembled. 相似文献
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Xinxiong Li Hongyan Xu Fanzhen Kong Ruihu Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2013,125(51):14014-14018
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Summary The adsorption behaviour of 26 metal ions on the strongly basic anion-exchange resin Bio Rad AG-1, X-8 has been examined in magnesium nitrate media. The salt concentration range from 0.50-3.0 M is covered in the presence of 0.1 M free nitric acid. The distribution coefficients of bismuth(III), thorium(IV) and uranium(VI) rise to the order of 1,000 in media of 0.1 M nitric acid with high salt strength, while most other elements are only weakly adsorbed as is also the case in pure nitric acid media. The system allows thorium(IV) and uranium(VI) to be concentrated simultaneously from 2.5 M nitrate media, so that it can be applied successfully to the determination of thorium and uranium in manganese nodules with consecutive Chromatographic elution from a single small resin column. The subsequent determination is carried out spectrophotometrically with Arsenazo III.
Anionenaustausch in Magnesiumnitratlösung. Anwendung zur Thorium- und Uranbestimmung in Manganknollen
Zusammenfassung Das Adsorptionsverhalten von 26 Metallionen wurde aus Magnesiumnitratlösung an dem stark basischen Anionenaustauscher Bio-Rad AG-1, X-8, untersucht. Die Salzkonzentration reichte von 0,5-3,0 M bei Gegenwart von 0,1 M freier Salpetersäure. Die Verteilungskoeffizienten von Bismut(III), Thorium(IV) und Uran(VI) reichen bei hoher Salzkonzentration bis zur Größenordnung von 1000, wogegen die meisten anderen Elemente nur schwach adsorbiert werden, was auch in reiner salpetersaurer Lösung der Fall ist. Dadurch können Th(IV) und U(VI) gleichzeitig aus 2,5 M Nitratlösung angereichert und mit gutem Erfolg in Manganknollen bestimmt werden, wobei nur eine einzige Elution von einer kleinen Harzsäule erforderlich ist. Die anschließende Bestimmung erfolgt spektralphotometrisch mit Arsenazo III.相似文献
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Daopeng Sheng Lin Zhu Xing Dai Chao Xu Peng Li Carolyn I. Pearce Chengliang Xiao Jing Chen Ruhong Zhou Tao Duan Omar K. Farha Zhifang Chai Shuao Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(15):5022-5026
99Tc contamination at legacy nuclear sites is a serious and unsolved environmental issue. The selective remediation of 99TcO4? in the presence of a large excess of NO3? and SO42? from natural waste systems represents a significant scientific and technical challenge, since anions with a higher charge density are often preferentially sorbed by traditional anion‐exchange materials. We present a solution to this challenge based on a stable cationic metal‐organic framework, SCU‐102 (Ni2(tipm)3(NO3)4), which exhibits fast sorption kinetics, a large capacity (291 mg g?1), a high distribution coefficient, and, most importantly, a record‐high TcO4? uptake selectivity. This material can almost quantitatively remove TcO4? in the presence of a large excess of NO3? and SO42?. Decontamination experiments confirm that SCU‐102 represents the optimal Tc scavenger with the highest reported clean‐up efficiency, while first‐principle simulations reveal that the origin of the selectivity is the recognition of TcO4? by the hydrophobic pockets of the structure. 相似文献
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Rokuro Kuroda Nobutaka Yoshikuni Katsunori Tateno 《Fresenius' Journal of Analytical Chemistry》1978,290(1):46-47
Ohne Zusammenfassung
Spectro photometric determination of thallium(I) and dimethylthallium compounds in small concentrations相似文献
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