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Preparation and Characterization of Gd^(3+)-doped Monodisperse TiO_2 Hollow microsphere

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Journal of the Chinese Ceramic Society 2015年第4期2卷 204-212页

作者： JI Feng SHANG Pengbo ZHENG Yuying College of Chemical Engineering and Technology Tianjin University College of Materials Science and Engineering Fuzhou University

Gd^(3+)-doped monodisperse TiO_2 hollow microspheres with various molar ratios of Gd^(3+)/TBOT were synthesized via a novel process, which involved the preparation of SiO_2 templates, deposition of Gd^(3+)-doped TiO_2 by sol-gel, SiO_2 coating, heat treatment to induce crystallization of TiO_2, and finally etching away the inner SiO_2 templates and outer SiO_2 layers. The synthesized samples were characterized by transmission electron microscopy(TEM), scanning electron microscopy(SEM), X-ray diffraction(XRD), diffuse reflection spectroscopy(DRS), specific surface area measurement(BET) and X-ray photoelectron spectroscopy(XPS), respectively. The photocatalytic activity of Gd^(3+)-doped samples was evaluated via photocatalytic degradation of Methyl orange under UV irradiation. The results show that the SiO_2 layers prevent aggregation of TiO_2 hollow microspheresand improve the thermal stability of the synthesized samples. Also, the photocatalytic activity of monodisperse TiO_2 hollow microspheres can be enhanced at the optimal molar ration of Gd^(3+)/TBOT of 0.7%.

关键词： Gd3+-doped hollow microsphere titania monodisperse photocatalysis

Preparation and Characterization of Polymeric microspheres Having Isotactic Poly(methacrylic acid) on Their Surfaces

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Chemical Research in Chinese Universities 2002年第1期18卷 61-64页

作者： CHEN Ming-qing LIU Xiao-ya YANG Cheng AKASHI Mitsuru School of Chemical and Material Engineering Southern Yangtze UniversityWuxi 214036P.R.China Department of Applied Chemistry and Chemical Engineering Faculty of EngineeringKagoshima UniversityKagoshima 890-0065Japan

A poly（ tert -butyl methacrylate）（PBMA） macromonomer was synthesized by anionic polymerization with bis（2,6-di- t -butyl phenoxy） methyl aluminum [MeAl（ODBP）2] as the initiator and trimethylsilylmethacrylate（TMSMA） as the end capping agent in dry THF. Then, a poly（methacrylic acid）（PMAA） macromonomer was obtained by means of hydrolysis reaction from the PBMA macromonomer in the presence of hydrochloric acid. The structures of the PBMA macromonomer were characterized by using 1H NMR. It was found that the resulted PBMA macromonomer has highly isotactic properties and the PMAA macromonomer has an end vinyl group on per polymer chain. The monodisperse polymeric microspheres, which consisted of polystyrene cores and PMAA branches on their surfaces, were prepared by the dispersion copolymerization of styrene with the PMAA macromonomer in an ethanol/water mixed solvent. It was found that the concentration of the PMAA macromonomer would affect the microsphere formation, the morphology and its size in the copolymerization system.

关键词： Macromonomer Isotactic structure Dispersion copolymerization microsphere

Characterization of Fe_3O_4/P(St-MPEO) Amphiphilic Magnetic Polymer microspheres

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Chemical Research in Chinese Universities 2002年第4期18卷 458-461页

作者： CHAN ALBERT S. C. YIP C. W. Open Laboratory of Chirotechnology and Department of Applied Biology and Chemical Technology Open Laboratory of Chirotechnology and Department of Applied Biology and Chemical Technology Hong Kong Polytechnic University Hong Kong P. R. ChinaHong Kong Polytechnic University Hong Kong P. R. China

Amphiphilic magnetic microspheres consisting of styrene and poly(ethylene oxide) macromonomer(MPEO) were prepared by dispersion copolymerization in the presence of Fe_3O_4 magnetic fluid in an ethanol/water medium. The sizes of the magnetic microspheres and their distribution were characterized by means of scanning electron microscopy(SEM). The surface morphology and the average surface roughness of the microspheres were investigated by virtue of atomic force microscopy(AFM). It was found that the microspheres exhibit microscopic phase-separate and the mean square surface roughness of the microspheres increases with increasing MPEO used in the copolymerization. The amphiphilic magnetic microspheres containing 0 4-3 5 mg/g hydroxyl groups could be prepared from MPEO with different concentrations and styrene.

关键词： Amphiphilic magnetic polymer microsphere Copolymerization

Triple and Double Photons Absorption Process and Down-Conversion Laser Emitting Investigation of Er-Ion Doped microsphere

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Journal of Modern Physics 2013年第12期4卷 1622-1626页

作者： Yantang Huang Peijing Zhang Yu Huang Changlei Guo 1Physics and Information Engineering College Fuzhou University Fuzhou China 2Department of Electronic Engineering Institute of Optoelectronic Technology Xiamen University Xiamen China Physics and Information Engineering College Fuzhou University Fuzhou China

We report a readily and cheap method to build taper optical fiber-Er3+ doped microsphere platform to investigate upconversion fluorescence emission and down-conversion laser oscillation with low threshold pump power. We demonstrate to dope Er3+ into silica microsphere surface by dipping a single-taper optical fiber into a certain concentration of erbium nitrate solution (Er(NO3)) , then dry it and use the electrical-arc of the optical fiber splicer to melt the tip of taper fiber to form the Er3+-doped silica microsphere due to surface tension induced. We also present a HF acid etching setup to fabricate low loss biconical optical taper fibers. We demonstrate the Er3+ doped silica microsphere triple photons and dual photons absorption process of up-conversion fluorescence emission and down-conversion laser oscillation spectra by using the optical tapered fiber to couple 976 nm/1534 nm pump light source.

关键词： Triple Photons Absorption Process Er3+ Doped microsphere Taper Optical Fiber Micro-Laser

MEMBRANE EMULSIFICATION SYSTEMS

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化工学报 2000年第S1期51卷 69-73页

作者： Liu Xiudong, Liu Qun, He Yang, Xiong Ying, Fu Yingli, Ma Xiaojun and Yuan Quan (Lab. of biomedical material engineering, Dalian Institute of Chemical Physics, CAS 116023)

Microcapsules (or microspheres) with small size and narrow size distribution have potential applications as carriers of proteins and polypeptides. However the conventional preparation methods severely limit their real applications. Membrane emulsification technology may become a new preparation method of microcapsules with monodisperse droplets, mild conditions, good stability, low energy consumption and easy to realize mass production. In this paper, studies on membrane emulsification systems and the possible existing problems are summarized, and primary attempts on preparing alginate/chitosan microcapsules are conducted.

关键词： membrane emulsification microcapsule microsphere

Cellulose Nanocrystals-Coated Polylactide(PLA) microspheres Obtained via a Pickering Emulsion Approach

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Journal of Donghua University(English Edition) 2017年第3期34卷 371-376页

作者：吴骏隋晓锋钟毅张琳萍毛志平徐红 Key Lab of Science and Technology of Eco-textile Ministry of Education College of Chemistry Chemical Engineering andBiotechnology Donghua University Shanghai 201620 China

In order to prepare cellulose nanocrystals( CNCs)-coated polylactide( PLA) microspheres for the use of drug delivery and tissue engineering,a Pickering emulsion route was applied. The stable Pickering emulsions were prepared using CNCs as efficient stabilizers without any additional surfactant. The microspheres were successfully fabricated after volatilization of the solvent. What's more,the size of microspheres could be controlled by fabrication parameters.

关键词： cellulose nanocrystals(CNCs) Pickering emulsion polylactide(PLA) microsphere

Dual growth factor-immobilized microspheres for tissue reinnervation

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Asian Journal of Pharmaceutical Sciences 2016年第1期11卷 154-155页

作者： Tae Ho Kim Se Heang Oh Dan Bi An Jin Ho Lee Hannam University Daejeon 305-811Republic of Korea Dankook University Cheonan 330-714Republic of Korea

It has been reported that various progenitor cells or stem cells and continuously released bioactive molecules can enhance the regeneration of muscles and thus help to treat chronic degenerative diseases,such as urinary/fecal incontinence and erectile dysfunction.However,the regeneration ofmuscles alone cannot be a fundamental cure of chronic degenerative diseases,because regenerated muscles with insufficient nerve connections subsequently lead tomuscle atrophy[1].

关键词： microsphere Basic fibroblast growth factor(BFGF) Nerve growth factor(NGF) Neurogenic differentiation Nerve regeneration

空心和核/壳含碳TiO_2微球的锂电存储性能（英文）

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Chinese Journal of Chemical Engineering 2014年第10期22卷 1153-1161页

作者： Songgyun Ri 邓洪贵周丽辉胡军刘洪来胡英 State Key Laboratory of Chemical Engineering Department of Chemistry East China University of Science and Technology

TiO2 microspheres containing carbon have been synthesized viaa one-pot hydrothermal process using CTAB as the mesoporous template and nanoparticle stabilizer and Ti(SO4)2and sucrose as titanium and carbon precursors,respectively. Through well designed calcinations, Ti O2 microspheres with various amounts of carbon-residue,such as core/shell C@TiO2, hollow neat H–TiO2, and hollow C/TiO2 composites, are obtained. When these microspheres are used as anode materials for lithium ion batteries, the lithium storage performance is significantly influenced by the structure and carbon-residue. With a thin shell of TiO2 nanoparticles and carbon-residue, the capacity of hollow C/TiO2 composites maintains at 143.3 m A·h·g-1at 0.5 C(83.5 m A·g-1) after 100 cycles.Moreover, after high rate charge/discharge cycles from 0.2 C to 20 C and back to 0.2 C again, the reversible capacity recovers atas high as 195.1 m A·h·g-1with respect to its initial value of 205.0 m A·h·g-1. The results of cycle voltammograms and electrochemical impedance spectroscopy further reveal that Li+insertion/extraction processes are reversible, and the diffusion coefficient of Li+in the hollow C/TiO2 composites is much higher than those of others, because the hollow structure can act as the ion-buffering reservoir and facilitate Li+transfer from both sides of the shell, and the carbon-residue in the shell improves the conductivity as well.

关键词： Lithium ion battery Titanium dioxide microsphere Hollow Core/shell Electrochemical properties

Development of biodegradable radiopaque microsphere for arterial embolization-a pig study

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World Journal of Radiology 2015年第8期7卷 212-219页

作者： Yi-Sheng Liu Xi-Zhang Lin Hong-Ming Tsai Hung-Wen Tsai Guan-Cheng Chen Syuan-Fong Chen Jui-Wen Kang Chen-Miao Chou Chiung-Yu Chen Department of Radiology College of Medicine National Cheng Kung University Department of Internal Medicine College of Medicine National Cheng Kung University Department of Pathology College of Medicine National Cheng Kung University

AIM: To develop a new type of calibrated, biodegradable, and imaging detectable microsphere and evaluated its embolization safety and efficacy on pig's liver and spleen. METHODS: Six kinds of pharmaceutical excipient were combined and atomized to form our microsphere. Twenty-four male Lanyu pigs weighing 25-30 kg were used. The arteries of spleen and liver were embolized with Gelfoam, Embosphere, or our microsphere. The serum biochemical tests, computed tomography(CT), liver perfusion scan, and tissue microscopy examination were done to evaluate the safety and efficacy of embolization. RESULTS: Radiopaque microspheres with a size ranging from 300 to 400 μm were produced. Embolization of hepatic and splenic artery of pigs with our microsphere significantly reduced the blood flow of liver and resulted in splenic infarction. The follow-up CT imaging and the microscopic examination showed intraarterial degradation of Gelfoam and microsphere. The blood testsdemonstrated insignificant changes with regards to liver and renal functions. CONCLUSION: Our microspheres, with the unique characteristics, can be used for transcatheter arterial embolization with effects equivalent to or better than Gelfoam and Embosphere in pigs.

关键词： microsphere biodegradable transcatheter microscopic pharmaceutical perfusion splenic biochemical narrow manufactured