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Chinese Journal of chemical engineering 2022年第5期35卷 15-21页

作者： Jianhua Feng Sen Xiong Li Ren Yong Wang college of material and chemical engineering Chuzhou UniversityChuzhou 239000China State Key Laboratory of materials-Oriented chemical engineering and College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China

Chromium(Cr)is a common heavy metal that has severe impacts on the ecosystem and human health.Capacitive deionization(CDI)is an environment-friendly and energy-efficient electrochemical purification technology to remove Cr from polluted water.The performance of CDI systems relies primarily on the properties of electrodes.Carbon-nanotubes(CNTs)membranes are promising candidates in creating advanced CDI electrodes and processes.However,the low electrosorption capacity and high hydrophobicity of CNTs greatly impede their applications in water systems.In this study,we employ atomic layer deposition(ALD)to deposit TiO_(2) nanoparticulates on CNTs membranes for preparing electrodes with hydrophilicity.The TiO_(2)-deposited CNTs membranes display preferable electrosorption performance and reusability in CDI processes after only 20 ALD cycles deposition.The total Cr and Cr(VI)removal efficiencies are significantly improved to 92.1%and 93.3%,respectively.This work demonstrates that ALD is a highly controllable and simple method to produce advanced CDI electrodes,and broadens the application of metal oxide/carbon composites in the electrochemical processes.

关键词： Carbon-nanotube membranes Atomic layer deposition Capacitive deionization Chromium removal

4-Tert-butyl-N′-((2-Hydroxynaphthalen-1-yl)methylene)Benzohydrazide:Synthesis,Crystal Structure and Recognition Properties

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Chinese Journal of Structural Chemistry 2018年第9期37卷 1426-1432页

作者：刘天宝彭艳芬桂美芳昌杰汪新 College of Chemical and Material Engineering Chizhou University

A new naphthol-based compound 1, C22 H22 N2 O2, has been designed and synthesized. The structure of the title compound 1 was confirmed by IR, 1 H NMR, 13 C NMR, H RMS, and X-ray single-crystal diffraction. The crystal belongs to the monoclinic system, space group P21/c, with a = 12.888（9）, b = 15.543（10）, c = 9.119（6）？, β = 94.05（3）°, V = 1822（2）？3, Z = 4, Dc = 1.263 g/cm3, Mr = 346.41, μ = 0.081 mm-1, F（000） = 736.0, the final R = 0.0452 and wR = 0.1142 for 3404 observed reflections with（I 〉 2σ（I））. The crystal structure of 1 is stabilized by O–H···N, N–H···O, C–H···O hydrogen bonds and π-π interactions. The spectroscopic studies of 1 toward various metal ions were also investigated in 25%（V/V） ethanol aqueous solution, and the result showed that it can selectively recognize Zn2＋ with fluorescence enhancement.

关键词： naphthol crystal structure Zn2＋ recognition property

High Damping and Mechanical Properties of Hydrogen-bonded Polyethylene materials with Variable Contents of Hydroxyls:Effect of Hydrogen Bonding Density

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Chinese Journal of Polymer Science 2017年第5期35卷 649-658页

作者： Lei Kan Xiao Ouyang Shan Gao Rui Li 马宁 Shi-hui Han 魏浩 Lian-he Liu college of material Science and chemical engineering Harbin Engineering University

Hydrogen bonding is considered to have significant effect on the interaction between polymeric chains and on the viscoelasticity of the polymeric materials. In this paper, we attempt to discuss the relationship between hydrogen bonding density and damping behavior and mechanical properties of polyethylene-based polymeric materials. For this reason, a series of pendant chain hydrogen bonding polymers （PCHBP） with different hydrogen bonding density （HBD） were prepared by quantitatively changing the content of pendent hydroxyl groups on the main chain of polyethylene. It was found that PCItBP with low HBD showed similar properties to polyethylene, indicating that the property of the materials was dependent mainly on the structure of the main chain. However, PCHBP with high HBD exhibited two tandpeaks and a platform of loss modulus as well as a high storage modulus （about 400 MPa） at the second tand peak temperature, demonstrating that a polymeric material with high strength and damping properties was obtained. More importantly, the maximum of loss modulus showed a linear increase with the HBD, indicating that a higher HBD greatly improved the damping properties of the polymeric materials.

关键词： Hydroxyls Polyethylene Hydrogen bonding Polymer damping

New Technology for Optimizing Melting Pool and Regulating Grain Formation in Laser Surface Remelting of Single Crystal Superalloys

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材料导报 2019年第4期33卷 569-570页

作者：金国 college of material Science and chemical engineering Harbin Engineering University

Nickel-base superalloys are materials of choice for manufacturing hot-section components in gas turbines due to their superior mechanical properties at high temperatures [1]. For maintaining and improving the properties, this kind of materials are often cast into single crystal form. Nevertheless, severe service conditions of high temperature and high pressure, often cause tip and platform damages.

关键词： Nickel-base manufacturing hot-section

Zirconium metal organic cages:From phosphate selective sensing to derivate forming

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Chinese chemical Letters 2022年第9期33卷 4415-4420页

作者： Ziyuan Gao Jia Jia Wentong Fan Tong Liao Xingfeng Zhang college of material and Chemistry&chemical engineering Chengdu University of TechnologyChengdu 610059China

Luminescent metal organic cages(MOCs)have attracted great interest as a unique class of sensing substrates.In this work,intrinsically fluorescent Zr-MOCs were successfully used as fluorescent probes for the sensitive and selective detection of phosphate anions in water and real samples.When the ligand and Zr ion clusters form a cage,the intrinsic fluorescence of the ligand was tuned from high to weak emission due to the ligand-to-metal charge transfer(LMCT)effect,and this weakened fluorescence can be restored by the addition of phosphate.The degree of fluorescence enhancement is positively correlated with the added phosphate concentration,and the efficacy of this strategy is demonstrated by a linear phosphate detection range of 5–500µmol/L and a detection limit of 1.06µmol/L.We discuss the interaction between phosphate and Zr in scattering spectrum and MS,respectively.In comparison to phosphate adsorption on Zr-metal organic frameworks(MOFs),where phosphate connects different numbers of cages,both blocking the LMCT effect and causing the cages to aggregate.We also found that the phosphate displaces the ligand from the cage when the phosphate concentration is further expanded,resulting in the formation of new derivatives.This derivative was shown to be useful as a Lewis acid catalyst and as a rare earth ion adsorbent.

关键词： Zirconium metal organic cage Phosphate sensing Derivant forming Fluorescence enhancement Mass spectrometry

Superelastic Radiative Cooling Metafabric for Comfortable Epidermal Electrophysiological Monitoring

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Nano-Micro Letters 2023年第10期15卷 449-462页

作者： Jiancheng Dong Yidong Peng Yiting Zhang Yujia Chai Jiayan Long Yuxi Zhang Yan Zhao Yunpeng Huang Tianxi Liu Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxi 214122People’s Republic of China college of Energy material and Chemistry College of Chemistry and Chemical EngineeringInner Mongolia UniversityHohhot 010021People’s Republic of China

Epidermal electronics with superb passive-cooling capabilities are of great value for both daytime outdoor dressing comfort and low-carbon economy. Herein, a multifunctional and skinattachable electronic is rationally developed on a porous all-elastomer metafabric for efficient passive daytime radiative cooling(PDRC) and human electrophysiological monitoring. The cooling characteristics are realized through the homogeneous impregnation of polytetrafluoroethylene microparticles in the styrene–ethylene–butylene–styrene fibers, and the rational regulation of microporosity in SEBS/PTFE metafabrics, thus synergistically backscatter ultraviolet–visible–near-infrared light(maximum reflectance over 98.0%) to minimize heat absorption while efficiently emit human-body midinfrared radiation to the sky. As a result, the developed PDRC metafabric achieves approximately 17℃ cooling effects in an outdoor daytime environment and completely retains its passive cooling performance even under 50% stretching. Further, high-fidelity electrophysiological monitoring capability is also implemented in the breathable and skin-conformal metafabric through liquid metal printing, enabling the accurate acquisition of human electrocardiograph, surface electromyogram, and electroencephalograph signals for comfortable and lengthy health regulation. Hence, the fabricated superelastic PDRC metafabric opens a new avenue for the development of body-comfortable electronics and low-carbon wearing technologies.

关键词： Passive radiative cooling Human electrophysiological monitoring Superelastic metafabrics Spectrally selective reflecting microfibers Liquid metals

Differentiation of qualified tea beverages from spoiled ones by the LC-MS-based analysis of their polycarboxylic acids

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Food Quality and Safety 2023年第1期7卷 138-144页

作者：康宇婷李城华李慧茹栗婧蒋可志 college of material Chemistry and Chemical EngineeringKey Laboratory of Organosilicon Chemistry and Material Technology of Ministry of EducationHangzhou Normal UniversityHangzhouChina

Polycarboxylic acids(PACs)are important metabolic products in almost all living bodies,yet current analytical methods for detection of PACs in tea beverages are still unsatisfactory due to the complex matrix and physicochemical properties of PACs.In this work,a rapid method was developed for the simultaneous determination of 7 PACs,including tartaric acid,α-ketoglutaric acid,malic acid,malonic acid,cis-aconitic acid,succinic acid,and fumaric acid,in beverages,based on selective removal of the matrix in combination with liquid chromatography–mass spectrometry(LC-MS)analysis.By stirring with activated carbon and the Na2CO3 solution,the matrix in beverages was selectively removed,and PACs were almost retained in the supernatant of diluted Na2CO3 solution.Under optimized parameters,the limit of quantitation for the PACs was in the range of 1–50 ng/mL,and the content of the PACs in 8 beverages was determined with the recovery range of 72.2%–122.5%.The contents of malic acid,malonic acid,and succinic acid in tea beverages were found to be greater than those in non-tea beverages.Moreover,the concentration of these PACs in beverages was found to be multiplied many times in their deterioration period,especially for fumaric acid andα-ketoglutaric acid.These results indicated that PACs can be selected as a criterion to differentiate qualified tea beverages from spoiled beverages.

关键词： Tea beverage deterioration polycarboxylic acid simultaneous determination liquid chromatography-mass spectrometry

Synthetic Features and Mechanism for the Preparation of Vinyl Chloride-co-Butyl Acrylate-co-Vinyl Acetate Terpolymer via Precipitation Polymerization

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Chinese Journal of Polymer Science 2023年第11期41卷 1714-1724,I0006页

作者： Chang-Tong Song Xian-Hong Zhang Dong Chen Yu-Hong Ma Wan-Tai Yang State Key Laboratory of chemical Resource engineering Beijing University of Chemical TechnologyBeijing 100029China college of material Science and engineering Beijing University of Chemical TechnologyBeijing 100029China

Without any type of su rfactant or dispersing agent,precipitation polymerization has great superiorities in both polymer synthesis and applications.In the present work,the polymerization of vinyl chloride(VC),n-butyl acrylate(BA),and vinyl acetate(VAc)are conducted in the precipitation polymerization system and series of their random terpolymers poly(vinyl chloride-co-n-butyl acrylate-co-vinyl acetate)(PCBV)are synthesized successfully.The effects of various polymerization conditions,including solvent polarity,temperature,initiator concentration,and monomer feed ratios on the polymerization kinetics,number-average molecular weight(M_(n)),and terpolymer composition are investigated systematically.The solvent and the monomer feed ratio are crucial factors not only for the polymer morphology,but also for the reaction kinetic.In the non-polar solvent such as n-hexane,the PCBV displays particle morphology when the composition of BA ratio lower than 10 wt%.Otherwise,the PCBV forms a uniform polymer phase and precipitates out from the mixture.In the polar solvent,e.g.,dimethyl carbonate(DMC)and ethanol,the PCBV polymer maintains a slurry state either in low or in high monomer feed ratio.Impressively,VC based ternary copolymer that obtained in n-hexane has much lower M_(n)(40 wt%)compared with emulsion and suspension polymerization.Additionally,the terpolymer can be easily sepa rated by simple centrifugation.

关键词： Precipitation polymerization Copolymerization Vinyl chloride Low molecular weight

Molecular simulation of penetration separation for ethanol/water mixtures using two-dimensional nanoweb graphynes

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Chinese Journal of chemical engineering 2019年第2期27卷 286-292页

作者： Wei Zhang Zhijun Xu Xiaoning Yang State Key Laboratory of material-Orientated chemical engineering College of Chemistry and Chemical Engineering Nanjing Tech University

Graphyne is expected to be a new-class of highly-efficient sieving membranes due to its controllable uniform pore structure and ultrathin single-atom thickness. Herein, we computationally investigate the permeation performance of liquid ethanol–water mixtures across polyporous two-dimensional γ-graphyne sheets. It was found that, in the mixture, ethanol with larger molecular diameter permeates faster through the graphyne pores than water. The simulations demonstrate that pristine graphynes could act as highly-efficient ethanol-permselective membranes for separation of ethanol–water mixtures, with ethanol permeability remarkably higher than conventional membranes. This separation mechanism is distinctly different from the molecular-size dependent sieving process. The stronger hydrophobic interfacial affinity between graphyne and ethanol makes ethanol molecules preferentially adsorb on graphyne surface and selectively penetrate through graphyne pores. This penetration mechanism provides new understanding of molecular transport through atomically thick two-dimensional nanoporous membranes and this work is expected to be valuable in the potential development of highly-efficient membranes for liquid-phase mixture separation.

关键词： Graphynes Membrane separation Ethanol/water Molecular simulation

Molecular oxygen-mediated selective hydroxyalkylation and alkylation of quinoxalin-2(1H)-ones with alkylboronic acids

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Chinese chemical Letters 2022年第4期33卷 2036-2040页

作者： Hongdou Zhang Jun Xu Yani Ouyang Xiaoguang Yue Chenxin Zhou Zhigang Ni Wanmei Li college of material Chemistry and Chemical EngineeringKey Laboratory of Organosilicon Chemistry and Material Technology of Ministry of EducationHangzhou Normal UniversityHangzhou 311121China

Herein, an efficient molecular oxygen-mediated method for the selective hydroxyalkylation and alkylation of quinoxalin-2(1 H)-ones with alkylboronic acids under transition-metal free conditions has been developed. This strategy demonstrates a broad scope of quinoxalin-2(1 H)-ones and alkylboronic acids, giving3-hydroxyalkylquinoxalin-2(1 H)-ones and 3-alkylquinoxalin-2(1 H)-ones in moderate-to-good yield. Control experiments reveal that a radical pathway is involved.

关键词： Quinoxalin-2(1H)-ones Molecular oxygen Alkyl boric acid C-C,C-O bond formations