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Chinese Journal of Chemistry 2013年第5期31卷 607-611页

作者： Ying Han Jiabin Guo Jing Cao Chuanfeng Chen Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and Function Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

Triptycene-derived cylindrical macrotricyclic host with two dibenzo-30-crown-lO cavities could form stable 1 ： 1 complexes with not only polyether linked bisparaquat derivative but also a self-folding A-D-A guest in solu- tion and/or solid state. Moreover, it was found that switchable processes between the host and both the bisparaquat derivative and the self-folding guest could be further controlled by potassium ions.

关键词： complexation macrotricyclic host paraquat triptycene switchable

complexation between uranyl(Ⅵ)and CMPO in a hydroxyl-functionalized ionic liquid:An extraction,spectrophotography,and calorimetry study

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Chinese Chemical Letters 2022年第7期33卷 3451-3455页

作者： Baihua Chen Jun Liu Hongyuan Wei Yuchuan Yang Xingliang Li Shuming Peng Yanqiu Yang Institute of Nuclear Physics and Chemistry CAEPMianyang 621900China

The extraction complexes of uranyl(Ⅵ)in HNO_(3)to a hydroxyl-functionalized ionic liquid(IL)phase,HOEtmimNTf2bearing CMPO,were *** possibly successive extraction complexes,UO_(2)L^(2+)(L=CMPO),UO2L_(2)^(2+) and UO_(2)L_(3)^(2+),were detected based on variable U/L ***(Ⅵ)prefers to be extracted as complex UO_(2)L_(3)^(2+),combining with the ions from HOEtmimNTf_(2) to construct a solid material through *** thermodynamics of complexes,UO_(2)L_(j)^(2+)(j=1-3),were studied by spectrophotometry and *** the formation reactions are principally driven by entropy,although a small part of the driving force of complexes UO_(2)L_(2)^(2+)and UO_(2)L_(3)^(2+) comes from *** on the thermodynamic properties for complex UO_(2)L_(3)^(2+),we provide a possible coordination mode in HOEtmim NTf_(2):the first CMPO molecule coordinates with UO_(2)^(2+) in a bidentate fashion while the others do in a monodentate *** results offer a thermodynamic insight into the formation behaviors of the uranyl(Ⅵ)/CMPO complexes involving the special IL HOEtmimNTf_(2),which is of significance to advance the novel IL extraction strategy.

关键词： Uranyl(Ⅵ) CMPO Ionic liquid Solvent extraction complexation Thermodynamics

Efficient purification of Al_(30) by organic complexation method

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Journal of Environmental Sciences 2019年第6期31卷 240-247页

作者： Libing Liu Qinxue Yang Pin Wang Feng Xiao Ruyuan Jiao Guangyu An Dongsheng Wang University of Chinese Academy of Sciences State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Faculty Materials Science and Chemistry China University of Geosciences

A method was developed for preparing high purity Al30O8(OH)56(H2O)_(24)^(18)+(Al30) through elimination of impurities by *** chloride II(PAC_(30))with Al_(c )content of 75%was adopted as the source of Al_(30).The PAC_(30)was prepared under conditions of total aluminum concentration 0.1 mol/L and OH^-/Al ratio 2.2 to obtain the highest content of Al_(30).A precipitation/metathesis method,organic solvent precipitation method and organic complexation method were examined to separate and purify Al_(30).It was found that only by the organic complexation method could high purity Al_(30)products be obtained in large yield *** the experiments,benzoic acid was used as the coordinating reagent to decompose the main impurity AlO_4Al_(12)(OH)_(24)(H_2O)_(12)^(7+)(Al_(13)),and the Al_(30)product could be obtained by precipitation and metathesis *** was noteworthy that the decomposition of impurities by benzoic acid could be completed in 2 *** Al_(30)product was characterized by Ferron assay,^(27)Al-NMR,SEM,XRD and *** results showed that the purity of the Al_(30)product could exceed 92%.

关键词： Polyaluminum chloride(PAC) Al13 Al30 Organic complexation Precipitation/metathesis

Dish-like higher-ordered palladium nanostructures through metal ion-ligand complexation

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Nano Research 2018年第6期11卷 3442-3452页

作者： Xi Yin Miao Shi Kam Sang Kwok Haidong Zhao Danielle L. Gray Jeffery A. Bertke Hong Yang Department of Chemical and Biomolecular Engineering University of Illinois at Urbana-Champaign MC-712 206 Roger Adams I Laboratory 600 S. Matthews Avenue Urbana Illinois 61801 USA George L. Clark X-ray Facility University of Illinois at Urbana-Champaign 505 S. Matthews Avenue Urbana Illinois 61801 USA

Unlike nucleation and growth in simple precipitation processes, described by the classical theory, metal nanoparticles formed in organic solvents with capping ligands often involve chemical reactions that occur homogeneously in solution or heterogeneously on the metal surface. These chemical reactions lead to the formation of intermediates that occurs in the process of deposition onto nuclei during the reduction. The understanding of these chemical reactions would enable a better design of functional metal nanocrystals, even those with unconventional hierarchical morphologies. In this study, we report the formation of dish-shaped nanostructures of palladium （Pd） obtained from palladium acetylacetonate （Pd（acac）2） in the presence of oleylamine and oleic acid. The process was correlated with the kinetic-controlled evolution of two-dimensional （2D） Pd nanosheets. The formation of Pd-ligand complexes was revealed using single-crystal X-ray diffraction, ultraviolet-visible spectroscopy, and mass spectrometry. These intermediates affected the formation kinetics of the 2D nanostructures and higher-ordered morphology of the nanodishes.

关键词： palladium nanoplates two-dimensional materials. complexation nucleation growth

Mechanism of aluminum complexation in oxidative activity of leaching bacteria in a fluoride-containing bioleaching system

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Rare Metals 2019年第1期38卷 87-94页

作者： Xiang Li Jian-Kang Wen Xiao-Lan Mo Wu Biao Dian-Zuo Wang Hong-Ying Yang National Engineering Laboratory of Biohydrometallurgy General Research Institute for Nonferrous Metals School of Metallurgy Northeastern University

Accumulation of toxic ions in leachate is one factor limiting bioleaching applications. The effect of fluoride ions on the growth of bioleaching microorganisms has been extensively emphasized. In this study, HF is found to be the toxic form of fluoride that affects the bacterial activity under acidic conditions. The added aluminum could compete with H^+ to complex with F-, thus significantly decrease the concentration of HF and finally reduce the toxicity of fluoride to bacteria. When F^-/Al^(3+)concentration ratio is 0.5:1.0, Fe^(2+) oxidation rate could reach 0.167 g·L^(-1)·h^(-1), close to that of the biotic control group(0.195 g·L^(-1)·h^(-1)). The competitive complexation mechanism of fluoride by AlF_n^(3-n) results in stability constants of AlF_n^(3-n) complex(7.00) that are larger than those of HF(3.18). The F^-/Al^(3+) concentration ratio in the medium could affect the speciation of AlF_n^(3-n) *** the decrease in F^-/Al^(3+) concentration ratio, the coordination numbers of AlF_n^(3-n) decrease. Finally, the feasibility of fluoride detoxification by aluminum ion is verified. This work has meaningful implications for fluoride-containing bacterial bioleaching systems.

关键词： Competitive complexation Detoxification Fluoride Aluminum Bioleaching

Self-Assembled Film of Tb^(3+) and Poly(3- Thiophene Acetic Acid) via Layer-by-Layer complexation Technique and Its Photoluminescence

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Journal of Rare Earths 2002年第5期20卷 333-338页

作者：辛颢李富友黄岩谊黄春辉 Lab. of Rare Earth Mat. Chem. Peking Univ. Beijing 100871 China

The layer by layer complexation technique of polymer and metal ion was successfully utilized to fabricate the ultrathin multilayer film of poly(3 thiophene acetic acid (PTAA) and Tb 3+ ion by dipping the substrates alternatively in polymer and Tb 3+ ion aqueous solutions. UV-vis measurement revealed that the absorbance has linearity with the bilayer number from layer to layer and the X ray photoelectron spectrum (XPS) confirmed the existence of Tb 3+ ion. The pH of both the polymer and TbCl 3 solutions influence the thickness dramatically while the concentration of the solutions is not so sensitive. The luminescent spectrum of the complex film shows the characteristic emission of Tb 3+ ion as well as the ligand indicating the formation of the complex.

关键词： rare earths self assembly terbium complexation layer by layer photoluminescence

Revealing unconventional host-guest complexation at nanostructured interface by surface-enhanced Raman spectroscopy

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Light(Science & Applications) 2021年第5期10卷 898-905页

作者： Gan-Yu Chen Yi-Bin Sun Pei-Chen Shi Tao Liu Zhi-Hao Li Si-Heng Luo Xin-Chang Wang Xiao-Yu Cao Bin Ren Guo-Kun Liu Liu-Lin Yang Zhong-Qun Tian State Key Laboratory of Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy Materials(iChEM)College of Chemistry and Chemical EngineeringXiamen UniversityXiamen361005China State Key Laboratory of Marine Environmental Science Fujian Provincial Key Laboratory for Coastal Ecology and Environmental StudiesCenter for Marine Environmental Chemistry&ToxicologyCollege of the Environment and EcologyXiamen UniversityXiamen361102China School of Electronic Science and Engineering(National Model Microelectronics College) Xiamen UniversityXiamen361005China Key Laboratory of Chemical Biology of Fujian Province Xiamen UniversityXiamen361005China

Interfacial host–guest complexation offers a versatile way to functionalize ***,the complicated interfacial environment and trace amounts of components present at the interface make the study of interfacial complexation very ***,taking the advantages of near-single-molecule level sensitivity and molecular fingerprint of surface-enhanced Raman spectroscopy(SERS),we reveal that a cooperative effect between cucurbit[7]uril(CB[7])and methyl viologen(MV^(2+)2^(I−))in aggregating Au NPs originates from the cooperative adsorption of halide counter anions I^(−),MV^(2+),and CB[7]on Au NPs ***,similar SERS peak shifts in the control experiments using CB[n]s but with smaller cavity sizes suggested the occurrence of the same guest complexations among CB[5],CB[6],and CB[7]with MV2+.Hence,an unconventional exclusive complexation model is proposed between CB[7]and MV^(2+)on the surface of Au NPs,distinct from the well-known 1:1 inclusion complexation model in aqueous *** summary,new insights into the fundamental understanding of host–guest interactions at nanostructured interfaces were obtained by SERS,which might be useful for applications related to host–guest chemistry in engineered nanomaterials.

关键词： materials. surface. complexation

Unravelling the effects of complexation of transition metal ions on the hydroxylation of catechol over the whole pH region

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Journal of Environmental Sciences 2022年第5期34卷 392-402页

作者： Zexiu An Jianfei Sun Qiong Mei BoWei Mingxue Li Ju Xie Maoxia He Qiao Wang Environment Research Institute Shandong UniversityQingdao 266237China School of Environmental and Materials Engineering Yantai UniversityYantai 264005China College of Safety and Environmental Engineering Shandong University of Science and TechnologyQingdao 266590China School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China

Catechol pollutants(CATPs)serving as chelating agents could coordinate with many metal ions to form various CATPs-metal *** information is available on the effects of complexation of metal ions on CATPs *** work presents a systematical study of·OH-mediated degradation of catechol and catechol-metal complexes over the whole pH range in advanced oxidation processes(AOPs).Results show that the pH-dependent complexation of metal ions(Zn^(2+),Cu^(2+),Ti^(4+)and Fe^(3+))promotes the deprotonation of catechol under neutral and even acidic *** radical adduct formation(RAF)reactions are both thermodynamically and kinetically favorable for all dissociation and complexa-tion species,and-OH/-O-group-containing C positions are more vulnerable to·OH *** kinetic results show that the complexation of the four metal ions offers a wide pH range of effectiveness for catechol *** pH 7,the apparent rate constant(k_(app))values for different systems follow the order of catechol+Ti^(4+)≈catechol+Zn^(2+)>catechol+Cu^(2+)>catechol+Fe^(3+)>*** mechanistic and kinetic results would greatly improve our understanding of the degradation of CATPs-metal and other organics-metal complexes in *** toxicity assessment indicates that the·OH-based AOPs have the ability for decreasing the toxicity and increasing the biodegradability during the processes of catechol degradation.

关键词： Catechol Metal ions complexation pH Degradation

Recent developments of surface complexation models applied to environmental aquatic chemistry

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Journal of Environmental Sciences 2001年第4期13卷 422-434页

作者： Liu, W.-X. Tang, H.-X. SKLEAC Res. Cntr. Eco-Environmental Sci. Chinese Academy of Sciences Beijing 100085 China

Based on numerous latest references, the current developments in surface complexation, surface precipitation and the corresponding models (SCMs and SPMs), were reviewed. The contents involved comparison on surface charge composition and layer-structure of solid-solution interface for the classical 1-pK and 2-pK models. In addition, the fundamental concept and relations of the new models, i. e., multi-site complexation (MUSIC) and charge- distribution (CD) MUSIC models were described as well. To avoid misuse or abuse, it must be emphasized that the applicability and limitation for each model should be considered carefully when selecting the concerned model(s). In addition, some new powerful techniques for surface characterization and analysis applied to model establishment and modification were also briefly introduced.

关键词： complexation Precipitation (chemical)

Concentration of linoleic acid from cottonseed oil by starch complexation

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Chinese Journal of Chemical Engineering 2019年第4期27卷 845-849页

作者： Dan Liang Yufeng Hu Weiting Ma Zhengtang Zhao Siqi Jiang Yichuan Wang Xianming Zhang State Key Laboratory of Heavy Oil Processing China University of Petroleum

The extraction of linoleic acid from fatty acids(FA) of the cottonseed oil using starch–FA complexes was developed for the first time. We showed that starch can form inclusion complexes of different strengths with FA and that the different strengths stem from the differences in chain length, degree of unsaturation, and position of double bonds of FA. The optimal separation conditions were determined as follows: The inclusion temperature is 69 °C, the inclusion time is 30 min, the starch/FA mass ratio is 10:1, and the ratio of the volume of methanol–water solution and the mass of FA is 18:1. Compared to urea inclusion complexation, starch complexation has milder reaction temperature and shorter reaction time. Under these conditions, linoleic acid can be concentrated from 38.9% to 70.04% by one-off extraction. Moreover, the experimental results demonstrate the almost perfect reusability of starch. These results show that starch complexation is a promising method that can be used to obtain highly concentrated linoleic acid from cottonseed oil.

关键词： Starch Linoleic acid Starch complexation Starch–FA complex Cottonseed oil