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Chinese Journal of Chemistry 2022年第5期40卷 597-602页

作者： Jianqiao Wang Huanhuan Zhang Yuguang Ma State Key Laboratory of Luminescent Materials and Devices Institute of Polymer Optoelectronic Materials and DevicesSouth China University of TechnologyNo.381 Wushan RoadTianhe DistinctGuangzhouGuangdong510640 China

Doping plays an essential role in the properties of conducting polymers.Film thickness not only has a direct influence on their photoelectric properties,but also affects the doping ability,which may lead to the decline of capacitance and electrochromic properties caused by incomplete doping.Therefore,it is essential to study the quantitative relationship between doping level and film thickness in application.Herein,empirical formula between doping level and thickness was obtained by studying the spectroelectrochemistry behaviors of two different electrochromic materials,poly(N,N'-bis(3,5-(2-thienyl)-phenyl)-1,6,7,12-tetrachloroperylene-3,4,9,10-perylenetetracarboxylic diimide)(poly(Th-Cl-PBI))and poly(3,4-ethylenedioxythiophene)(PEDOT).The doping level is verified to be correlated to the reciprocal of the 3^(rd)power of film thickness.Experimental results fit these formulas very well,giving correlation coefficient R^(2)higher than 0.99.The optical contrast prediction of these two electrochromic materials is also used to verify this relationship formula.For the first time,we quantitatively connect these two important parameters of conducting polymers,doping level and thickness.

关键词： Doping Electrochemistry Polymers Electrochromism Thickness dependence

Insight into microbiologically induced corrosion performance of magnesium in tryptic soy broth with S.aureus and E.coli

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Journal of Materials Science & Technology 2022年第20期115卷 221-231页

作者： Tao Liang Huanhuan Zhang Haobo Pan Ying Zhao Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen 518055China University of Chinese Academy of Sciences Beijing 100049China

In this research,microbiologically induced corrosion(MIC)performance of magnesium in tryptic soy broth with S.aureus or E.coli were systematically explored.The results showed that magnesium in biotic solution presented higher mass loss,thicker degradation product layer and more severe pitting corrosion compared to abiotic solution after 24 h of immersion.Electrochemical measurements including EIS spectra and polarization curve further suggested that the corrosion rate of Mg in biotic solution increased during the early stage owing to the decrease of p H,which was originated from the consumption of glucose and the resulting accumulation of acidic metabolites.However,corrosion rate subsequently decreased because of the reduction of acidic metabolites and production of alkaline compound as well as the corrosion protection provided by the corrosion product and biofilm.Moreover,the corrosion rate of magnesium in high concentration of S.aureus and E.coli solution was larger than that in low concentration of S.aureus and E.coli solution,respectively during the initial stage,but subsequently presented a reverse variation.In addition,more severe corrosion of magnesium was observed in S.aureus solution in comparison with E.coli solution.These results suggested that the MIC performance of magnesium was closely related to the concentration and species of bacteria.

关键词： Magnesium S.aureus E.coli Microbiologically induced corrosion

Synthesis and characterization of a novel collector for the desulfurization of fine high-sulfur bauxite via reverse flotation

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Particuology 2023年第8期79卷 64-77页

作者： Gan Cheng Jianqiang zhang huanhuan Su Zhanyun zhang Zhengzhou Non-ferrous Metals Research Institute Co.Ltd. Aluminum Corporation of ChinaZhengzhou450041China College of Chemistry and Chemical Engineering Henan Polytechnic UniversityJiaozuo454000China Collaborative Innovation Center of Coal Work Safety and Clean High Efficiency Utilization Henan Polytechnic UniversityJiaozuo454000China

Bauxite is one of the main raw materials in the alumina industry.Fine high-sulfur bauxite flotation desulfurization is a great challenge presently.This study aims to synthesize nanoparticle collectors(NPCs)by emulsion polymerization to improve the abovesaid flotation desulfurization process.The physicochemical properties of high-sulfur bauxite were analyzed,and the experimental conditions for the synthesis of NPCs were optimized.The interaction mechanism between NPCs and pyrite was studied via fundamental analyses including SEM(Scanning Electron Microscope),FT-IR(Fourier Transform Infrared spectoscopy),Zeta-potential,XPS(X-ray Photoelectron Spectroscopy),and wettability.Under the closed-circuit flotation flowsheet of"one roughing-two cleaning-three scavenging",aluminum concen-trate with a yield of 85.91%and sulfur content of 0.56%were obtained using a common collector.However,with the addition of the novel NPC,aluminum concentrate with a yield of 85.70%and sulfur content of 0.36%could be obtained by a simpler flowsheet of"one roughing-one cleaning-two scav-enging".The improvement in flotation performance is suggested to be contributed by the addition of spherical NPC,which induced a rougher and more hydrophobic pyrite surface.

关键词： Bauxite Flotation desulfurization Nanoparticle collector Pyrite

Hygroscopic properties of sodium and potassium salts as related to saline mineral dusts and sea salt aerosols

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Journal of Environmental Sciences 2020年第9期32卷 65-72页

作者： Huanhuan Zhang Wenjun Gu Yong Jie Li Mingjin Tang State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China Department of Civil and Environmental Engineering Faculty of Science and TechnologyUniversity of MacaoAvenida da UniversidadeTaipaMacaoChina University of Chinese Academy of Sciences Beijing 100049China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China

Mineral dust,soil,and sea salt aerosols are among the most abundant primary inorganic aerosols in the atmosphere,and their hygroscopicity affects the hydrological cycle and global climate.We investigated the hygroscopic behaviors of six Na-and K-containing salts commonly found in those primary organic aerosols.Their hygroscopic growths as a function of relative humidity(RH) agree well with thermodynamic model prediction.Temperature dependence of deliquescence RH(DRH) values for five of those salts was also investigated,which are comparable to those in literature within 1%-2% RH,most showing negative dependence on temperature.Hygroscopic growth curves of real-world soil and sea salt samples were also measured.The hygroscopic growths of two more-hydroscopic saline soil samples and of sea salt can be predicted by the thermodynamic model based on the measured water-soluble ionic composition.The substantial amounts of water-soluble ions,including Na+and K+,in saline soil samples imply that even nascent saline soil samples are quite hygroscopic at high-RH(>80%) conditions.For three less-hygroscopic dust samples,however,measurements showed higher water uptake ability than that predicted by the thermodynamic model.The small amount of water taken up by less-hygroscopic dust samples suggests that dust particles might contain thin layers of water even to very low RH.The results of this study provide a comprehensive characterization of the hygroscopicity of Na-and K-containing salts as related to their roles in the hygroscopic behaviors of saline mineral dusts and sea salt aerosols.

关键词： prediction. salts dust

TEGDME Electrolyte Additive for High-performance Zinc Anodes

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Chemical Research in Chinese Universities 2023年第6期39卷 1037-1043页

作者： zhang Weiguo zhang Chong WANG Hongzhi WANG huanhuan Department of Applied Chemistry School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350P.R.China

Aqueous zinc ion batteries(AZIBs)are expected to have a wide range of applications for large-scale electrochemical energy storage systems,but their practical application is severely limited by the presence of zinc dendrites,hydrogen evolution reactions(HER),corrosion reactions,and other problems.Electrolyte optimization is considered to be one of the most effective methods for improving zinc anodes due to its simplicity,low production cost and remarkable effectiveness in suppressing zinc dendrite growth.In this paper,a tetra(ethylene glycol)dimethyl ether(TEGDME)electrolyte additive was used to improve the stability of the zinc anode by adding 0.1 g/L TEGDME to the conventional ZnSO_(4) electrolyte to prepare a mixed electrolyte.The effect of TEGDME on the side reactions of zinc anode was first assessed by linear sweep voltammetry(LSV)and potentiodynamic polarization.The effect of TEGDME on the structure and morphology of zinc surfaces was observed using an X-ray diffractometer(XRD)and a scanning electron microscope(SEM).And finally,the electrochemical performance of Zn|Zn symmetric cells,Zn||Ti asymmetric cells and Zn-MnO_(2) full cells with ZnSO_(4)+TEGDME electrolyte was tested by cyclic voltammetry(CV)and galvanostatic cycling.The results show that the addition of TEGDME improves the surface wettability of the Zn anode and reduces the growth of dendrites through solvation structure modulation to suppress HER and zinc corrosion.Thus,TEGDME keeps the Zn anode to maintain a flat surface during charging and discharging,improving the reversibility of plating/stripping.The cycle life of the Zn||Ti asymmetric cell was improved and the Coulombic efficiency was 100%after 100 cycles.The Zn||Zn symmetric cells can be cycled stably for 1800 h at a current density of 1 mA/cm^(2) and a fixed capacity of 1 mA·h/cm^(2),while the capacity retention of the Zn-MnO_(2) full cell can be effectively improved from 51.46%to 68.29%at 100 cycles.By using TEGDME electrolyte additives,the cycle life of aqueous zinc ion batteries can be

关键词： Aqueous zinc ion battery Zinc dendrite Hydrogen evolution reaction Solvation structure Cycle life

Bioinspired Topological Surfaces for Mitigating Water,Thermal and Energy Crises

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Accounts of Materials Research 2022年第2期3卷 199-212页

作者： Wei zhang Yuankai Jin Siyan Yang Huanhuan Zhang Zuankai Wang Department of Mechanical Engineering and Research Center for Nature-Inspired Engineering City University of Hong KongHong Kong 999077P.R.China

CONSPECTUS:The remarkable advances in technical and industrial fields have stimulated the world’s economic prosperity and population growth while also exacerbating the global water,thermal,and energy crises.To mitigate these crises,numerous large-scale devices have been constructed to harvest water,dissipate heat,and generate energy,yet they still encounter several bottlenecks,such as bulky size and climatic and/or geographic constraints.In contrast,miniature and portable water-based devices have demonstrated their tremendous potential in water harvesting and thermal/energy management due to the ubiquitous existence,large phase-change latent heat,and abundant kinetic energy of water.Owing to the strong dependence of their performance on the interfacial interactions between water and a surface,designing novel surface topology,in both physical and chemical aspects,is of practical importance to impart them with the ability to control the interfacial interaction/exchange among water,heat,and energy in an efficient,precise,and programmable manner.

关键词： interfacial precise topology

A secure visual framework for multi-index protection evaluation in networks

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Digital Communications and Networks 2023年第2期9卷 327-336页

作者： Xiang Wu huanhuan Wang Yongting zhang Ruirui Li Institute of Medical Information Security Xuzhou Medical UniversityXuzhou221000China Xuzhou Hengjia Electronic Technology Co.LTD Xuzhou221008China

Mining the core value of Industrial Internet of Things(IIoT)data safely and reducing the risk of malicious attacks are the inherent requirements of industrial data visualization.Visualization technology has become the main tool for data aggregation,mining and analysis of IIoT data through graphical representation.However,visualization technology still has two shortcomings in big data calculation and analysis scenarios.On the one hand,visual results will lead to the disclosure of sensitive privacy.On the other hand,most visualization tools can't provide an interactive framework for users to select the suitable solutions.To address these problems,we present an open accessible Visual framework based on Differential Privacy theory(VisDP),which provides Multi-index Quantitative comprehensive Evaluation technology(MQE)for data mining results.Considering the advantages of interactive mechanism,VisDP provides rich optional schemes,including the operating web,calling API and the downloading SDK.Finally,we verify the availability and privacy of MQE through mathematical proofs,analyze the hospital medical waste detection system that actually applies the framework,and the experimental results have showed the effectiveness and practicality of the proposed platform.

关键词： Visualization interactive platform Privacy preserving Differential privacy Data mining

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铝及铝合金板带材加工新技术

有色金属加工 2020年第3期49卷 6-8页

作者：张建辉张欢欢中色科技股份有限公司河南洛阳471039

文章介绍了近年来铝及铝合金板带材加工中出现的一些新技术,对其基本情况和相应的优缺点进行了分析和阐述,为相关人员提供参考。

关键词： 4辊超薄快速铸轧无酸无皂乳液纤维素 NEXCAST铸机边部加热装置

Palladium-Catalyzed Intramolecular Dehydrogenative Arylboration of Alkenes

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Chinese Journal of Chemistry 2022年第20期40卷 2437-2444页

作者： Chenchen Zou Hongli Wu Yuqi Ji Penglin zhang huanhuan Cui Genping Huang Chun zhang Institute of Molecular Plus Tianjin Key Laboratory of Molecular Optoelectronic ScienceDepartment of ChemistrySchool of ScienceTianjin UniversityTianjin300072 China State Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin300071 China

The palladium-catalyzed borylative cyclization via C—H activation has been developed.By this chemistry,the indole-fused dihydro-pyrrole motif,which is a kind of important unit in natural products and bio-active molecules,could be constructed and installed with a boric ester group.Furthermore,the utilities of products have been illustrated by the study of further transformations.Importantly,by using chiral ligand,the enantioselectivity of this borylative cyclization reaction could be controlled.Moreover,the borylative mechanism,which should proceed through a Pd(II)/Pd(IV)catalytic cycle,has been proposed based on the DFT calculations.

关键词： Palladium Dehydrogenative coupling reaction Indole-fused dihydro-pyrrole Boron

A Cathodic Electrochromic Material Based on Thick Perylene Bisimide Film with High Optical Contrast and High Stability

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CCS Chemistry 2022年第4期4卷 1347-1356页

作者： Jianqiao Wang Weitao Ma Hailong Wang Zengqi Xie Huanhuan Zhang Yuguang Ma State Key Laboratory of Luminescent Materials and Devices Institute of Polymer Optoelectronic Materials and DevicesSouth China University of TechnologyTianhe DistrictGuangzhou 510640

Cathodic electrochromic materials realized by n-type doping of conducting polymers are scarce.Even with limited cases reported in the literature,long-term stability is an urgent problem to be solved.Herein,we report a high performance and stable cathodic electrochromic material,poly(Th-Cl-PBI),based on a perylene bisimide function core.Due to its high electropolymerization efficiency and low steric hindrance of thiophene groups,perylene bisimide,which generally does not dissolve and form film easily,can grow to the sufficient thickness of 350 nm for wide-range spectral modulation and large-capacity energy storage.The optical contrast of optimized film with a thickness of 240 nm reaches as high as 69.1% at 520 nm,94.1% at 760 nm,and 95.7% at 680 nm.Theoretical simulation based on the Lambert–Beer law also verifies this optical contrast dependent on film thickness.Besides,during the transition between the neutral state and radical anion state,it maintains 90.2% of the electrochemical activity after 4000 cycles,and the transmittance spectrum remains stable after 2000 cycles.The cation size effect on cathodic electrochromic process and cyclic stability has been investigated.

关键词： cathodic electrochromism perylene bisimide n-type doping film thickness optical contrast stability