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Measurement of surface crystallinity of PAA and PAANa coatings and its effect on hydrophilicity of coatings

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中国有色金属学会会刊：英文版 2003年第4期13卷 988-993页

作者：潘春跃刘清泉徐先华陈振华 school of Chemistry and chemical engineering school of Materials Science and engineering

The solutions of poly(acrylic acid)(PAA), poly(acrylic acid sodium)(PAANa) were coated on aluminium fins by roll coating method. The coatings with different crystallinity were obtained by varying baking time and temperature. Their surface crystallinity and surface tension were measured, and their spreading speed constant and equilibrium contact angle were tested also. The correlation of surface crystallinity, surface tension, spreading speed constant and surface hydrophilicity was discussed. It is demonstrated that surface tension and spreading speed constant increase, while equilibrium contact angle declines with increasing surface crystallinity of coatings, that is to say, the hydrophilicity of coatings is improved with surface crystallinity of coatings increasing.

关键词： PAA PAANa 结晶度测量亲水性涂层

Superelastic damping of TiNi alloy wire under heavy mechanical shock in structural engineering

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中国有色金属学会会刊：英文版 2004年第2期14卷 278-283页

作者：陈庆福田文彦左晓宝倪立峰 school of Materials and chemical engineering school of Civil Structural engineering

Based on superelastic damping application in structural engineering, the damping characteristics of commercial Ti-50.8Ni(mole fraction, %) alloy have been systematically studied by adjusting frequency of mechanical shock, temperature, stress, strain and number of cycling. The results show that at extremely low frequency mechanical shock at room temperature, the superelastic damping capacity increases with controlled strain, and such capacity of each cycle is greater than 50%. When the frequency of mechanical shock is 0.10.3 Hz, the superelastic damping capacity above room temperature is relatively large at high strain; when the temperature approaches to M_d, the damping begins at low stress. For specimen cycled under 0.5 Hz, above 6% strain mechanical shock at relatively high temperature, further large-strain cycling exhibits more than 35% damping capacity. The superelastic damping of trained specimen is relatively stable at 2050 ℃ and 0.10.5 Hz frequency mechanical shock.

关键词： TiNi合金结构工程振动超弹性阻尼机械工程高阻尼合金

Experimental study of power consumption, local characteristics distributions and homogenization energy in gas–liquid stirred tank reactors

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Chinese Journal of chemical engineering 2019年第2期27卷 278-285页

作者： Facheng Qiu Zuohua Liu Renlong Liu Xuejun Quan Changyuan Tao Yundong Wang school of Chemistry and chemical engineering Chongqing University school of Chemistry and chemical engineering Chongqing University of Technology Department of chemical engineering Tsinghua University

In this paper, the power consumption, the vertical local void fraction and the local gas–liquid interfacial area are investigated in the aerated stirred tank reactors(STRs) equipped with a rigid-flexible impeller. Meanwhile, the regressive correlation based on power consumption and interfacial area is proposed. Then a novel homogenization energy(HE = RSDPtm) expression based on power consumption and local interfacial area is redefined and used to indicate the mixing efficiency. The optimal operating mode is selected based on the change of the HE value. This paper can provide research ideas for structural optimization of stirred reactors.

关键词： Stirred tank Gas-liquid two-phase Power consumption Local characteristics Homogenization energy

Using a novel adsorbent macrocyclic compound cucurbit[8]uril for Pb^(2+) removal from aqueous solution

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Journal of Environmental Sciences 2016年第12期28卷 3-12页

作者： Xuzhuo Sun Bo Li Dongjin Wan Ning Wang school of chemical and chemical engineering Henan University of Technology

In this study, cucurbit[8]uril （CB[8]） was utilized as a kind of new adsorbent to remove Pb^2＋ ions from aqueous solution. With the solution pH increased from 2 to 6, the removal efficiency of adsorption increased from 55.6% to 74.5%correspondingly. The uptake of Pb^2＋ increased rapidly in the initial 30 min, and then the adsorption rate became slower. The Pseudo-second order model could be used to interpret the adsorption kinetics satisfactorily; and the rate determining step in Pb^2＋ adsorption onto CB[8] was the external mass transfer step. Equilibrium isotherm study reveals that the Langmuir model gave a better fitting result than Freundlich model. The maximum adsorption capacity calculated by the Langmuir model was 152.67 mg/g for 298 K, 149.70 mg/g for 313 K and 136.42 mg/g for 323 K, respectively. The adsorption is a spontaneous process of exothermic nature. The effect of the adsorbent dosage and the influences of solution pH and co-existing cations were also investigated. The CB[8] was synthesized and characterized by 1H NMR, IR, ESI-MS spectra, SEM-EDAX, Zeta-potential and BET-analysis. The adsorption mechanism was due to the coordination between CB[8] molecule and Pb^2＋ ions.

关键词： Cucurbituril Adsorption Kinetics Equilibrium Pb^2+

Unmodified and positively charged gold nanoparticles for sensitive colorimetric detection of folate receptor via terminal protection of small molecule-linked ss DNA

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Science China Chemistry 2016年第6期59卷 770-775页

作者： Min Wang Fangzhen Li Bingying Jiang Junqiang Xu Shuo Li Yun Xiang Ruo Yuan school of Chemistry and chemical engineering Chongqing University of Technology school of Chemistry and chemical engineering Southwest University

The detection of protein/small molecule interactions plays important roles in drug discovery and protein/metabolite interactions in biology. In this work, by coupling the terminal protection of small molecule-linked ss DNA strategy with the unmodified and positively charged gold nanoparticle((+)Au NP) nanoprobes, we have developed a sensitive and simple colorimetric sensor for the detection of folate receptor, a highly expressed protein in many kinds of malignant tumors. The target folate receptor binds the folate moieties of the folate-linked ss DNA through high affinity interactions and protects the protein-bound ss DNA from digestion by exonuclease I. The protected ss DNA thus adsorbs the((+)Au NP) through electrostatic interactions, leading to a red-to-blue color change of the sensing solution for sensitive colorimetric detection of folate receptor at the sub-nanomolar level. Besides, this colorimetric sensor shows high selectivity toward folate receptor against other control proteins. The developed sensor avoids the modification/conjugation of the Au NP nanoprobes and the involvement of any expensive instruments for signal transduction in protein detection. Featured with these obvious advantages, the colorimetric sensor strategy demonstrated herein can be easily expanded for sensitive and convenient detection of various protein/small molecule interactions.

关键词： colorimetry positively charged gold nanoparticles sensor terminal protection folate receptor

Analysis of meniscus beneath metastable droplets and wetting transition on micro/nano textured surfaces

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Chinese Physics B 2018年第8期27卷 439-449页

作者： Yaniie Li Xiangqin Li Tianqing Liu Weiguo Song school of chemical engineering Daliat7 University of TechnologyDalian 116024China school of pharmacy Weifang Medical UniversityWeifang 261053China

Tile expressions of interface flee energy （IFE） of composite droplets with meniscal liquid-air interlhce in metastable state on nlicro/nano textured snrfaces were formulated. Then tile parameters to describe the meniscus were determined based on the principle of minimtun 1FE. Furthermore, the IFE barriers and the necessary and sufficient conditions of drop wetting transition fl＇om Cassie to Wenzel were analyzed and the corresponding criteria were lk^rmulated. The results show that the liquid-air interface below a composite droplet is fiat when the post pitches are relatively small, but in a shape of curved meniscus when the piteches are comparatively large and the curvature depends on structural parameters. The angle between meniscus and pillar wall is just equal to the supplementary angle of intrinsic contact angle of post material. The calculations also illustrate that Cassie droplets will transform to Wenzel state when post pitch is large enough or when drop volume is sufficiently small. The opposite transition from Wenzel to Cassie state, however, is unable to take place spontaneously because the energy barrier is always positive. Finally, the calculation results of this model are well consistent with tile experimental obserwttions in literatures for the wetting transition of droplets from Cassie to Wenzel state.

关键词： interface free energy droplet wetting transition energy barrier

Kinetic study of oxidative coupling of methane over Mn and/or W promoted Na_2SO_4/SiO_2 catalysts

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Journal of Natural Gas Chemistry 2011年第4期20卷 428-434页

作者： M.Ghiasi A.Malekzadeh S.Hoseini Y.Mortazavi A.Khodadadi A.Talebizadeh school of Chemistry Damghan University school of chemical engineering Ferdowsi University of Mashhad school of chemical engineering University of Tehran

A comprehensive kinetic model for oxidative coupling of methane（OCM）over Mn and/or W promoted Na2SO4/SiO2 catalysts was developed based on a micro-catalytic reactor *** methane conversion and ethylene,ethane,carbon monoxide and carbon dioxide selectivities were obtained in a wide operating condition range of 750 - 825-C,CH4/O2=2.5 - 10 and contact time=267 - 472 kg s *** networks of six models with different rate equation types were compared *** kinetic rate parameters of each reaction network were estimated using linear regression or genetic algorithm optimization method（GA）.A reaction network suggested by Stansch et *** OCM was found to be the best one and was further used in this *** suggested model could predict the experimental results of OCM reaction within a deviation range of ± 20%.

关键词： oxidative coupling of methane(OCM) kinetic modelling genetic algorithm fixed-bed reactor

Comparative studies on flotation of illite,pyrophyllite and kaolinite with Gemini and conventional cationic surfactants

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中国有色金属学会会刊：英文版 2009年第2期19卷 446-453页

作者：夏柳荫钟宏刘广义黄志强常庆伟李鑫钢 school of chemical engineering and Technology Tianjin University school of Chemistry and chemical engineering Central South University

To search a novel class of effective silicate mineral collectors,the Gemini quaternary ammonium salt surfactant(butane-α,ω-bis(dimethyl dodeculammonium bromide),12-4-12) and its corresponding conventional monomeric surfactant(dedecyl trimethyl ammonium bromide,DTAB) were adopted to comparatively study the flotation behaviors of illite,pyrophyllite and kaolinite. Three silicate minerals with the Gemini surfactant as collector reveal floatability far better than with the corresponding traditional one. At pH 6,the best recoveries of illite,pyrophyllite and kaolinite with 3.5×10-4 mol/L 12-4-12 are 99.2%,91.7% and 99.6%,respectively. The fluorescence and contact angle measurement were also conducted for the further investigation of surfactants aggregation behavior and silicate mineral surface hydrophobic properties. FTIR spectra analysis and electrokinetic analysis show that the mechanism of adsorption of collector molecules on mineral surfaces is almost identical for the electronic attraction and hydrogen bonds effect. The superior collecting power of dimeric collector may be attributed primarily to its special structure and its essential properties.

关键词：阳离子表面活性剂浮选行为伊利石高岭石叶腊石双子座 Gemini表面活性剂季铵盐表面活性剂

Multi-component assembly of luminescent rare earth hybrid materials

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Journal of Rare Earths 2019年第2期37卷 113-123页

作者： Qiuping Li Bing Yan school of Materials and chemical engineering Ningbo University of Technology school of chemical Science and engineering Tongji University

This review focuses on the recent research progress in the multi-component assembly of luminescent rare earth hybrid materials, which is based on the luminescent rare earth compounds and two or more other building units, including the other photoactive species. It covers the multi-component luminescent rare earth hybrids which was assembled with different(a) organic-inorganic polymeric units,(b)nanoporous units,(c) nanoparticle composites or(d) other developing special units. Finally, future challenges and opportunities in this field are discussed. Herein it mainly focuses on the work of Yan's group in recent years.

关键词： Multi-component assembly Rare earth ions Hybrid materials Luminescence