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Nano Research 2016年第1期9卷 230-239页

作者： Xilai Jia yunfeng lu Fei Wei State Key Laboratory of Heavy Oil Processing China University of Petroleum Beijing 102249 China Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical Engineering TsinghuaUniversity Beijing 100084 China Department of Chemical and Biomolecular Engineering University of California Los Angeles CA 90095 USA

Nanomaterials with electrochemical activity are always suffering from aggregations, particularly during the high-temperature synthesis processes, which will lead to decreased energy-storage performance. Here, hierarchically structured lithium titanate/nitrogen-doped porous graphene fiber nanocomposites were synthesized by using confined growth of Li4Ti5O12 （LTO） nanoparticles in nitrogen-doped mesoporous graphene fibers （NPGF）. NPGFs with uniform pore structure are used as templates for hosting LTO precursors, followed by high-temperature treatment at 800 ~C under argon （Ar）. LTO nanoparticles with size of several nanometers are successfully synthesized in the mesopores of NPGFs, forming nanostructured LTO/NPGF composite fibers. As an anode material for lithium-ion batteries, such nanocomposite architecture offers effective electron and ion transport, and robust structure. Such nanocomposites in the electrodes delivered a high reversible capacity （164 mAh.g-1 at 0.3 C）, excellent rate capability （102 mAh-g-1 at 10 C）, and long cycling stability.

关键词： lithium titanate nitrogen-doped porousgraphene fibers lithium-ion batteries

Another strategy to assess sustainable development

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Ecological Economy 2006年第2期2卷 140-151页

作者： Chen yunfeng lu Genfa State Key Lab of Pollution Control and Resources Reuse School of Environment. Nanjing University Nanjing 210093 P.R. China

The goal of sustainoble development is to preserve sustainabitity trod simultaneously prevent catastrophe in a man-land .system. However, almost all the existing approaches to assessing sustainable development are to measure the sustainability. namely appraise from the obverse side of the sustainable development. So it seems necessary to attack the same task on the reverse, namely to measure the passibility of eatostrophe. In this paper, with a case study of Tianjin, China. we employ catastrophe theory and models to integrate Tianjin＇s sustainable development indicators, and then deduce the catastrophe risk index （ CRI） to present the level of catastrophic possibility in the city. Applying catastrophe theory, is a new strategy to assess sustainable development and shows great practical significance, especially for those developing regions or countries, who always give more priority to their economy and therefore have more obligation to make sure whether their social economic activities might bring forth any ecological environment catastrophe. Besides, being both qualitative and quantitative, the approach could be employed to explore not only static characteristics bat also dynamic mechanism of man-land system. Although our work is only a maiden attempt and still calls for further effort to improve it, the case study of Tianjin in this paper would assure as the great promising future to apply, catastrophe theory to sustoinable devetopment modeling,

关键词： Sastoinable development modeling Catastrophe theory Catastrophe sisk index (CRI) Man-land system

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Spontaneous and continuous anti-virus disinfection from nonstoichiometric perovskite-type lanthanum manganese oxide

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Progress in Natural Science:Materials International 2015年第3期25卷 191-196页

作者： Ding Weng Chao Lei Ting-Ting Wu Ren Sun Meiqing Shen yunfeng lu Department of Chemical and Biomolecular Engineering University of California Department of Orthopedic Surgery Brigham and Women's HospitalHarvard Medical School Key Laboratory for Green Chemical Technology of State Education Ministry School of Chemical Engineering and Technology and State Key Laboratory of EnginesTianjin University Department of Molecular and Medical Pharmacology University of California

Viral pathogens have threatened human being’s health for a long time, from periodically breakout flu epidemics to recent rising Ebola virus disease. Herein, we report a new application of nonstoichiometric Perovskite-type LaxMn O3(x ? 1, 0.95, and 0.9) compounds in spontaneous and continuous disinfection of viruses. Perovskite-type LaxMn O3(x ? 1, 0.95, and 0.9) is well-known for their catalytic properties involving oxidization reactions, which are usually utilized as electrodes in fuel cells. By utilizing superb oxidative ability of LaxMn O3(x ? 1, 0.95, and 0.9),amino acid residues in viral envelope proteins are oxidized, thus envelope proteins are denatured and infectivity of the virus is neutralized. It is of great importance that this process does not require external energy sources like light or heat. The A/PR/8/34H1N1 influenza A virus(PR8) was employed as the sample virus in our demonstration, and high-throughput disinfections were observed. The efficiency of disinfection was correlated to oxidative ability of LaxMn O3(x ? 1, 0.95, and 0.9) by EPR and H2-TPR results that La0.9Mn O3 had the highest oxidative ability and correspondingly gave out the best disinfecting results within three nonstoichiometric compounds. Moreover, denaturation of hemagglutinin and neuraminidase, the two key envelope proteins of influenza A viruses, was demonstrated by HA unit assay with chicken red blood cells and NA fluorescence assay, respectively. This unique disinfecting application of La0.9Mn O3 is considered as a great make up to current sterilizing methods especially to photocatalyst based disinfectants and can be widely applied to cut-off spread routes of viruses, either viral aerosol or contaminated fluid, and help in controlling the possibly upcoming epidemics like flus and hemorrhagic fever.

关键词： Disinfect Influenza A virus LaxMnO3 Nonstoichiometric Perovskite

Efficient Synthesis of PbTe Nanoparticle Networks

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Nano Research 2010年第10期3卷 685-693页

作者： Qiangfeng Xiao Ding Weng Zhenglong Yang Javier Garay Minjuan Zhang yunfeng lu Chemical and Biomolecular Engineering Department University of CaliforniaLos AngelesCA 90095USA Mechanical Engineering Department University of CaliforniaRiversideCA 92521USA Materials Research Department Toyota Motor Engineering and Manufacturing North AmericaInc.1555 Woodridge Ave.Ann ArborMI 48105USA

The synthesis of semiconductor nanocrystalline networks using weak capping ligands in aqueous media has been ***,includingβ-cyclodextrin,D-(+)-glucose,D-glucosamine,lactobionic acid,sucrose,and starch were chosen as weak ligands to facilitate the formation of PbTe nanoparticle *** nanoparticle size,ranging from 5 nm to 30 nm,can be tuned by manipulating the temperature and *** a similar strategy,more complicated nanostructures including carbohydrate spheres@PbTe core-shell structures and Te@carbohydrate@PbTe multilayered submicron cables have been *** is a general approach which can be easily extended to the fabrication of other semiconductor networks,including PbSe and Bi2Te3 using carbohydrates and ethylenediaminetetraacetic acid(EDTA),respectively,as ligands.

关键词： Lead telluride nanoparticle network core shell structures thermoelectric carbohydrate

Enhanced structural stability of adenovirus nanocapsule

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Progress in Natural Science:Materials International 2014年第2期24卷 171-174页

作者： Ding Weng Ziyue Karen Jiang Jing Jin Lily Wu yunfeng lu Chemical and Biomolecular Engineering University of California at Los Angeles Tissue Engineering Laboratories VA Boston Healthcare System Department of Orthopaedic Surgery Brigham and Women's Hospital Harvard Medical School Molecular and Medical Pharmacology University of California at Los Angeles Getein Biotechnology Co. Ltd.

Application of viral vector in gene therapy and vaccination is still limited by their structural stability, which significantly increased avoidable cost in storage and transportation. Herein a non-covalent conjugated low-pH degradable nanocapsule has been adopted to stabilize viral vectors. By utilizing a luciferase expressing adenovirus, AdCMVluc, we succeeded in a raise of over 11 folds in AdCMVluc’s structural stability after 12 days storage at 4 1℃.

关键词： Non-covalent nanocapsule Adenovirus Structural stability

Fabrication of porous scaffolds with protein nanogels

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Science China Chemistry 2011年第6期54卷 961-967页

作者： ZHU Qi YAN Ming HE Lin ZHU XinYuan lu yunfeng YAN DeYue State Key Laboratory of Metal Matrix Composites: School of Chemistry and Chemical Engineering Shanghai Jiao Tong University Shanghai 200240 China Department of Chemical & Biomolecular Engineering University of California Los Angeles 90055 USA Instrumental Analysis Center Shanghai Jiao Tong University Shanghai 200240 China

A novel type of porous scaffold was fabricated from single protein nanogels. The nanogels with single protein as core and crosslinked polymer network as shell were prepared through a two-step procedure including surface acryloylation and in situ radical polymerization. The formation of single protein nanogels was verified by matrix assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometer, transmission electron microscopy (TEM) and dynamic light scattering (DLS) analyses. Subsequently, the porous scaffolds were fabricated through a solvent evaporating process of aqueous nanogel solutions. The porous scaffolds were characterized by Fourier transform infrared (FTIR), scanning electronic microscopy (SEM), atomic force microscopy (AFM), and fluorescence microscopy. Interestingly, the obtained porous nanogel scaffolds presented multi-level porous morphologies with macro and nano scale pores, providing better spaces and microenvironments than normal macro porous scaffolds. Cell proliferation assay of nanogels showed low cytotoxicity. Considering that both the protein species and polymer constitutes can be pre-designed and adjusted, these multi-level porous nanogel scaffolds are promising candidates for tissue culture applications.

关键词： protein nanogel porous scaffold tissue culture

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Nanocapsules of oxalate oxidase for hyperoxaluria treatment

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Nano Research 2018年第5期11卷 2682-2688页

作者： Ming Zhao Duo Xu Di Wu James W. Whittaker Robert Terkeltaub yunfeng lu Department of Chemical and Biomolecular Engineering University of California Los Angeles Los Angeles CA 90095 USA Division of Environmental and Biomolecular Systems Oregon Health and Sciences University Beaverton OR 97006-8921 USA Division of Rheumatology Allergy and Immunology San Diego VA Medical Center 3350 La Jolla Village Drive San Diego CA 92161 USA

Enzyme therapeutics have great potential for the treatment of systemic disorders such as urolithiasis and nephrocalcinosis, which are caused by the excessive accumulation of oxalate. However, exogenous enzymes have short half-lives in vivo and elicit high immunogenicity, which largely limit the therapeutic outcomes. Herein, we report a delivery strategy whereby therapeutic enzymes are encapsulated within a thin zwitterionic polymer shell to form enzyme nanocapsules. The strategy is exemplified by the encapsulation of oxalate oxidase （OxO） for the treatment of hyperoxaluria, because as-synthesized OxO nanocapsules have a prolonged blood circulation half-life and elicit reduced immunogenicity. Our design of enzyme nanocapsules that enable the systemic delivery of therapeutic enzymes can be extended to various biomedical applications.

关键词： enzyme therapeutics hyperoxaluria oxalate oxidase protein delivery long circulation nanomedicine

Nitrogen-rich carbon spheres made by a continuous spraying process for high-performance supercapacitors

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Nano Research 2016年第11期9卷 3209-3221页

作者： Fei Sun Haobin Wu Xin Liu Fang Liu Huihui zhou Jihui Gao yunfeng lu School of Energy Science and Engineering Harbin Institute of Technology Harbin 150001 China Department of Chemical and Biomolecular Engineering University of California Los Angeles CA 90095 USA

Supercapacitors have high power densities, high efficiencies, and long cycling lifetimes; however, to enable their wider use, their energy densities must be significantly improved. The design and synthesis of improved carbon materials with better capacitance, rate performance, and cycling stability has emerged as the main theme of supercapacitor research. Herein, we report a facile synthetic method to prepare nitrogen-rich carbon particles based on a continuous aerosol- spraying process. The method yields particles that have high surface areas, a uniform microporous structure, and are highly N-doped, resulting in a synergism that enables the construction of supercapacitors with high energy and power density for use in both aqueous and commercial organic electrolytes. Furthermore, we have used density functional theory calculations to show that the improved performance is due to the enhanced wettability and ion adsorption interactions at the carbon/electrolyte interface that result from nitrogen doping. These findings provide new insights into the role of heteroatom doping in the capacitance enhancement of carbon materials; in addition, our method offers an efficient route for large-scale production of doped carbon.

关键词： nitrogen doping carbon spheres scalable supercapacitors density functional theory(DFT)

Synthesis of Monodisperse CexZr1-xO2 Nanocrystals and the Size-Dependent Enhancement of Their Properties

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Nano Research 2011年第5期4卷 494-504页

作者： Yuewei Zhang Jing Wen Jun Wang Daocheng Pan Meiqing Shen yunfeng lu Key Laboratory for Green Chemical Technology of State Education Ministry School of Chemical Engineering ＆ Technology Tianjin University Tianjin 300072 China Department of Chemical ＆ Biomolecular Engineering University of California Los Angeles CA 90095 USA

Monodisperse CexZr1-xO2 nanocrystals have been synthesized using a simple two-phase approach; adjusting the ratio of precursors used, amount of capping agent used, reaction time and temperature affords precise control over their composition, structure and size. Size-dependent enhancement of oxygen-storage capacity and kinetics of oxygen storage and release were observed. Systematic studies were conducted in order to understand the size-dependent enhancement of these properties. This work provides important insights into the synthesis and fundamental understanding of multi-component nanocrystals with a large variety of applications.

关键词： Nanocrystals CexZr1-xO2 size-dependent

Measurement of GaAs start duration in different solution concentration using infrared images

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Chinese Science Bulletin 2008年第6期53卷 932-936页

作者： LIU Lin YE YuTang WU yunfeng FANG Liang lu JiaJia School of Opto-Electronic Information University of Electronic Science and Technology of China Chengdu 610054 China

This paper proposes a new infrared method to measure the start duration of GaAs substrate in chemi- cal etching. When etching starts, the temperature of liquid-film will change because of heat release in the chemical reaction. As a result, the start duration of GaAs can be tested by collecting real-time in- frared thermal images in the course of temperature variation. Both theoretical analysis and experi- mental results show that the line shape liquid film of a 2-mm width is a good monitoring subject. By making use of the grey distribution change of a certain cross section of the line shape liquid film, the start duration of reaction between GaAs and H2SO4-H2O2-H2O is obtained. The start durations of reac- tion between GaAs substrate and H2SO4:H2O2:H2O (=5:1:50 and 15:3:50) solution are about 0.2 s and 0.3―0.4 s, respectively. This result and relative method will impulse the research of wet chemical etching technology of GaAs and so on.

关键词：红外线辐射时间实时监测液体薄膜砷化镓化学腐蚀

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