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Effects of copper and manganese cations on cerium-based conversion coating on galvanized steel:Corrosion resistance and microstructure characterizations

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Journal of Rare Earths 2022年第6期40卷 1002-1006,I0006页

作者： Farzaneh Khast Mesbah Saybani Ali Asghar Sarabi Dariani Corrosion engineering and material Protection Group Bandar Abbas CampusAmirkabir University of TechnologyTehranIran department of Maritime engineering Amirkabir University of TechnologyTehranIran department of Color and polymer engineering Amirkabir University of TechnologyTehranIran

The cerium conversion coating(CeCC) containing copper and manganese cations was applied to the galvanized steel.The microstructure and the composition of specimen were analyzed by field emission scanning electron microscopy(FE-SEM) and energy dispersive spectroscopy(EDS).Electrochemical impedance spectroscopy(EIS) and polarization tests were conducted in 3.5 wt% NaCl solution to investigate the coating corrosion resistance.The results show that there are improvements in corrosion resistance and microstructure of CeCC containing copper and manganese cations but copper ions increase corrosion resistance of CeCC from 5800 to 27000 Ω·cm^(2).

关键词： Conversion coating Galvanized steel EIS Copper Manganese Rare earths

Reversal of circularly polarized luminescence direction and an“onoff”switch driven by exchange between UV light irradiation and the applied direct current electric field

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Science China Chemistry 2022年第10期65卷 1945-1952页

作者： Kun Yao Zheng Liu Hang Li Dan Xu Wen-Hua Zheng Yi-Wu Quan Yi-Xiang Cheng Jiangsu Key Laboratory of Advanced Organic materials School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Key Laboratory of High Performance polymer material and Technology of Ministry of Education Department of Polymer Science and EngineeringSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

We report the rational design of a dual stimulus-activated quaternary chiral emission nematic liquid crystals(Q-N*-LCs)containing light-driven chiral dopant R-S-R-1,a static chiral dopant S-2 and an achiral Nile Red(NR)in a nematic liquid crystal(SLC1717).The dopant R-S-R-1 acts as a dynamic chiral donor and an energy donor,and the achiral NR serves as a circularly polarized luminescence(CPL)emitter and energy acceptor.Interestingly,this kind of Q-N*-LCs appears reversal CPL emission direction(L-CPL)using 365 nm UV light irradiation compared with the initial state(R-CPL).Most importantly,the“On-Off”CPL switch behavior of Q-N*-LCs can be repeatedly driven by revoking or rearranging the applied direct current(DC)electric field.An OR chiral information logic gate demonstrates that this dual driven Q-N*-LCs can be potentially used for chiral information storage and coding.

关键词： chiral supramolecular liquid crystals circularly polarized luminescence light and electricity dual stimuli-activated Förster resonance energy transfer

Rheological Properties of Konjac Glucomannan/SiO_2/Organic-Borate Gels

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Journal of Wuhan University of Technology(materials Science) 2009年第4期24卷 575-580页

作者：吴力立张超灿 department of polymer materials and engineering School of Material Sciences and EngineeringWuhan University of Technology

A series of thermoreversible konjac glucomannan gels crosslinked by organic borate were prepared. Required amount of hydrophilic SiO2 was added into the konjac glucomannan solutions before the crosslinking reaction, The gel network was formed through the crosslinking reaction between borate ions dissociated from organic borate and the cis-diol hydroxyl groups on the mannose units of polysaccharide chains. The rheological properties of the complex gels were studied by dynamic viscoelastic measurement. The gelation kinetics of the complex gels was studied and the critical getation points of the gels were exactly determined by the Winter-Chambon criterion. The effects of temperature and composite ratio on the shear storage modulus （G＇）, the loss modulus （G＂） and the sol-gel transition points were investigated.

关键词： konjac glucomannan Si02 organic borate rheological properties

Dewetting Behavior of Hydrogen Bonded polymer Complex Film under Hydrothermal Condition

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Chinese Journal of polymer Science 2018年第9期36卷 1036-1042页

作者： Chao Su Song-Mei Ma Geng-Xin Liu Shu-Guang Yang State Key Laboratory for Modification of Chemical Fibers and polymer materials Center for Advanced Low-dimension Materials College of Material Science and Engineering Donghua University department of polymer Science The University of Akron

Hydrogen-bonded polymer complex films with the thickness ranging from 50 nm to 2400 nm were prepared by layer-by-layer （LbL） assembly of poly（2-ethyl-2-oxazoline）（PEOX） and poly（acrylic acid）（PAA）. The dewetting behavior of PEOX/PAA films under hydrothermal condition was investigated. It was found that the dewetting occurred at solid-liquid interface, and the typical morphologies such as holes, irregular cellular structure, and droplets were observed. Atomic force microscopy （AFM） revealed the initial rupture of the film. Microscopic Raman and infrared （IR） imaging demonstrated that the PEOX and PAA chains remained association during the dewetting process.

关键词： Hydrogen-bonding polymer complex Dewetting

Optically Active Helical Polyisocyanides Bearing Chiral Phosphine Pendants: Facile Synthesis and Application in Enantioselective Rauhut-Currier Reaction

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Chinese Journal of polymer Science 2018年第2期36卷 163-170页

作者： Li Zhou Ling Shen Jian Huang Na Liu Yuan-Yuan Zhu Zong-Quan Wu department of polymer Science and engineering School of Chemistry and Chemical Engineering and Anhui Key Laboratory of Advanced Catalytic Materials and Reaction Engineering Hefei University of Technology School of material and Chemical engineering Bengbu University

Three novel enantiopure phenyl isocyanide monomers with BH3-protected phosphine functional group were designed and synthesized. polymerization of these monomers using a alkyne-Pd（II） complex as a catalyst led to the formation of respective helical polyisocyanides in high yields with controlled molecular weights（Mns） and narrow molecular weight distributions（Mw/Mns）. Removing the protecting BH3 groups afforded helical poly（phenyl isocyanide）s bearing phosphine pendants. Thanks to the chiral induction of monomer, the isolated helical polyisocyanides showed high optical activity, as revealed by circular dichroism（CD） and absorption spectroscopies and polarimetry. The helical structures of these polymers were quite stable in various organic solvents with different polarities and in a wide temperature range. Moreover, these helical polymers could be used as organocatalysts and showed good performance in enantioselective cross Rauhut-Currier reaction. The enantiomeric excess（ee） values of the isolated products of cross Rauhut-Currier reaction could be up to 90%. The polymer organocatalysts could be easily recovered from the reaction mixtures and reused at least five times in the reaction without significant loss of their enantioselectivities and catalytic activities.

关键词： Helical polymer Polyisocyanide Coordination polymerization polymer catalyst

Synthesis of Poly(ethylene glycol) Functionalized Star-shaped Tricationic Imidazolium Based Ionic Liquid

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Chinese Journal of polymer Science 2015年第2期33卷 245-255页

作者： Di Zhang 殷俊 Fei He Ni-lin Ge Zong-quan Wu 丁运生 Key Laboratory of Advanced Functional materials and Devices Anhui Province Department of Polymer Material and Engineering School of Chemistry and Chemical Engineering Hefei University of Technology

We report on the preparation of a well-defined star-shaped tricationic ionic liquid possessing three arms of poly（ethylene glycol） functionalized imidazolium rings. Remarkable solubility was found in most of the organic solvents we used. Thermogravimetric analysis（TGA） exhibited excellent thermal stability and two distinct decomposition temperatures were attributed to two kinds of chemical degradation. Differential scanning calorimetry（DSC） was further employed to investigate the thermal phase transitions, that three different signals（Tg, Tc, and Tm） were shown upon the second heating process. Moreover, CH2Cl2 solution of the ionic liquid expressed an excitation-wavelength dependent fluorescence response, leading to the facile modulation of photoluminescence behavior. This work represents an example of utilizing molecular design to construct novel ionic liquids and endow further potential to be used in the engineering materials.

关键词： Ionic liquid Imidazole Tricationic Excitation-wavelength dependent Photoluminescence

Effect of nano powder(Al2O3-CaO)addition on the mechanical properties of the polymer blend matrix composite

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Defence Technology（防务技术） 2020年第2期16卷 425-431页

作者： Hayder Abbas Sallal Alaa AAbdul-Hamead Farhad Mohammad Othman material engineering department University of TechnologyBaghdadIraq

This work describes the preparation and study of the properties of composite nanoparticles prepared by the sol-gel method which consists of two materials(Al2 O3-CaO),and study the effect of these nanoparticles on the mechanical behavior of a polymer blend(EP 4%+96%UPE).The powder was evaluated by X-ray diffraction analysis,scanning electron microscopy analysis(SEM),particle size analysis,and energy dispersive X-ray analysis(EDX).The mechanical behavior of the co mposite material was assessed by tensile test,bending test and hardness test.The evaluation results of the composite nanoparticles showed good distribution of the chemical composition between aluminum oxide and calcium oxide,smoothness in particles’size at calcination in high and low temperatures,formation of different shapes of nanoparticles and different(kappa and gamma)phases of the Al2 O particles.The results of mechanical behavior tests showed marked improvement in the mechanical properties of the resulted composite material,especially at 1.5%,compared with polymer blend material without nano powder addition.The tensile properties improved about(24 and 14.9)%and bending resistance about(23.5 and16.8)%and hardness by(25 and 22)%when adding particles of size(63.8 and 68.6)respectively.Therefore,this reflects the efficiency of the proposed method to manufacture the nanoco mposite powder and the possibility of using this powder as a strengthening material for the composite materials and using these composite materials in bio applications,especially in the fabrication of artificial limbs.

关键词： Composite nanoparticles Sol-gel method polymer blend matrix Nanocomposites Mechanical properties

MONODISPERSE MICRON-SIZED POLYACRYLAMIDE PARTICLES SYNTHESIZED BY DISPERSION polymerIZATION

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Chinese Journal of polymer Science 2007年第3期25卷 277-283页

作者：侯信 department of polymer Science and engineering College of Material Science and EngineeringTianjin UniversityTianjin 300072China

Monodisperse micron-sized polyacrylamide （PAM） particles with a regular shape have been successfully prepared through dispersion polymerization of the monomer using a rotary reactor. FTIR and NMR spectroscopic results demonstrated the formation of PAM. POM and TEM observations revealed that PAM particles had a regular shape and good dispersity. A thick layer of surfactant （PVP） still existed on PAM particles after multiple centrifugation and ultrasonic re-dispersion in ethanol, which indicates a strong interaction between PVP and PAM. The effects of various polymerization factors on the average size of PAM particles have also been studied.

关键词： Dispersion polymerization Polyacrylamide Rotary reactor

C/Cu多孔微球固载Co3O4纳米片作为锂离子电池的高性能负极材料

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Science China materials 2023年第12期66卷 4575-4586页

作者：孙逊张珺张华然曹余良周金平 Hubei engineering Center of Natural polymer-based Medical materials Engineering Research Center of Organosilicon Compounds&Materials of Ministry of EducationDepartment of ChemistryWuhan UniversityWuhan 430072China College of material engineering Xuzhou Vocational College of Industrial TechnologyXuzhou 221000China

过渡金属氧化物(TMOs)用作电极材料时,会在循环过程中产生严重的体积变化,并且其自身的导电率也较低,因此它的电化学性能较差.设计和开发独特的TMOs纳米结构并将其与导电碳基底相结合是改善其电化学性能的有效策略.本工作中,我们设计了... 详细信息

过渡金属氧化物(TMOs)用作电极材料时,会在循环过程中产生严重的体积变化,并且其自身的导电率也较低,因此它的电化学性能较差.设计和开发独特的TMOs纳米结构并将其与导电碳基底相结合是改善其电化学性能的有效策略.本工作中,我们设计了一种C/Cu多孔微球,并通过原位合成在碳壁上垂直生长Co_(3)O_(4)纳米片.作为导电基底,C/Cu多孔微球提供了多尺度孔隙网络和大的电极/电解质接触界面,显著改善了电子和离子扩散动力学.原位合成的Co_(3)O_(4)纳米片牢牢地固定在碳壁上,从而提高了复合微球在长期循环中的结构稳定性.得益于独特的结构特征,用作锂离子电池负极材料的C/Cu@Co_(3)O_(4)复合多孔微球表现出优异的倍率性能、高充电比容量和出色的循环稳定性.

关键词： C/Cu microspheres multiscale pore structure chitinderived carbon mesoporous Co_(3)O_(4)nanosheets anode materials