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science china(Technological sciences) 2009年第1期52卷 10-14页

作者： XIE Dan1, ZANG Yongyuan1, LUO Yafeng1, REN TianLing1, LIU LiTian1 & DANG ZhiMin2 1 Institute of Microelectronics, Tsinghua university, beijing 100084, china 2 college of material science and engineering, beijing university of chemical technology, beijing 100029, china Institute of Microelectronics Tsinghua University Beijing 100084 China college of material science and engineering Beijing University of Chemical Technology Beijing 100029 China

BiFeO3/PZT multilayer capacitor was prepared on Pt(100)/Ti/SiO2/Si(100) substrate. PZT buffer layer was derived by MOCVD method (label: PZT1) and sputtering method (label: PZT2) respectively. XRD analysis indicated that high (110) orientation of BFO in the BFO/PZT1 structure was achieved. SEM analysis indicated a better microstructure in the BFO/PZT1 structure compared with BFO/PZT2. The remnant polarization of the BFO/PZT1 was 82.5 μC/cm2 at an applied voltage of 8 V, compared with that of 25.2 μC/cm2 in the BFO/PZT2 structure. The BFO/PZT1 multilayer exhibited little polarization fatigue (<1.5%) upon 1×1010 switching cycles, at an applied voltage of 4 V. The leakage current density was about 2×10?7 A/cm2 at an applied voltage 4 V, in the BFO/PZT1 capacitor. All the results indicated that PZT can act as an inducing layer to the BFO and the MOCVD derived PZT has more inducing effect to the BFO thin film at room temperature.

关键词： BFO PZT MOCVD properties FeRAM

Constructing S-scheme charge separation in cobalt phthalocyanine/oxygen-doped g-C_(3)N_(4) heterojunction with enhanced photothermal-assisted photocatalytic H_(2) evolution

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Rare Metals 2024年第1期43卷 198-211页

作者： Wei-Long Shi Zheng Xu yu-Xing Shi Ling-Ling Li Jia-Lin Lu Xin-Hai sun Xin Du feng Guo Chang-yu Lu School of material science and engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212003JiangsuChina college of Chemistry Zhengzhou UniversityZhengzhou 450001China School of Water Resource and Environment Hebei Province Key Laboratory of Sustained Utilization and Development of Water RecourseHebei Center for Ecological and Environmental Geology ResearchHebei Geo UniversityShijiazhuang 050031China

Hydrogen acquisition from solar energy is an effective way to address energy crisis,which makes the development of efficient photocatalysts become the main direction of scientific ***,cobalt phthalocyanine/oxygen-doped g-C_(3)N_(4)(CoPc/OCN) S-scheme heterojunction photocatalyst was designed by coupling multi-step calcination with solvothermal method for enhanced photothermal-assisted photocatalytic H_(2) *** multistep calcined g-C_(3)N_(4) is easier for O-doping formation,and the ethanol solvothermal strategy is utilized to enhance the dispersion of CoPc on OCN nano sheet surface and forms sufficient S-scheme heterojunction through *** addition,the active sites and excellent photothermal properties of CoPc itself further improve the integrated photocatalytic activity of CoPc/OCN S-scheme *** optimal photocatalytic hydrogen evolution rate of CoPc/OCN S-scheme heterojunction photocatalyst reached 9.56 mmol·g^(-1)·h^(-1),which is 2.69 and 1.23 times higher than that of CN and OCN,*** work provides a valuable design idea and scheme for enhancing the multi-factor co-assisted photocatalytic H_(2) evolution performance.

关键词： Photothermal Photocatalytic H_(2)evolution Cobalt phthalocyanine Oxygen-doped g-C_(3)N_(4) Sscheme heterojunction

engineering Shewanella-re duce d graphene oxide aerogel biohybrid to efficiently synthesize Au nanoparticles

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Journal of materials science & technology 2024年第1期168卷 50-61页

作者： Baocai Zhang Shulin Shao Huan yu Qijing Liu Sicheng Shi Qingyuan Wu Zijie Wu Yiyu feng Yifei Wang Xi sun Deguang Wu feng Li Hao Song Frontier science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering(Ministry of Education) Tianjin UniversityTianjin 300072China Collaborative Innovation Center of chemical science and engineering(Tianjin) School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China beijing Advanced Innovation Center for Soft Matter science and engineering Beijing University of Chemical TechnologyBeijing 100029China School of materials science and engineering Tianjin UniversityTianjin 300350China college of Biological engineering Tianjin Agricultural UniversityTianjin 300384China Department of Brewing engineering Moutai InstituteLuban AveRenhuai 564507China

Biosynthesizing Au nanoparticles(AuNPs)from gold-bearing scraps provides a sustainable method to meet the urgent demand for ***,it remains challenging to efficiently biosynthesize AuNPs of which the diameter is less than 10 nm from a trace amount of Au^(3+)concentration at the level of tens ***,we constructed an exoelectrogenic cell(eCell)-conductive reduced-graphene-oxide aero-gel(rGA)biohybrid by assembling Shewanella sp.S1(SS1)as living biocatalyst and rGA as conductive ad-sorbent,in which Au^(3+)at trace concentrations would be enriched by the adsorption of rGA and reduced to AuNPs through the extracellular electron transfer(EET)of *** regulate the size of the synthe-sized AuNPs to 10 nm,the strain SS1 was engineered to enhance its EET,resulting in strain RS2(pYYD-P tac-ribADEHC&pHG13-P_(bad)-omcC in SS1).Strain RS2 was further assembled with rGA to construct the RS2-rGA biohybrid,which could synthesize AuNPs with the size of 7.62±2.82 nm from 60 ppm Au^(3+)*** eCell-rGA biohybrid integrated Au^(3+)adsorption and reduction,which enabled AuNPs biosyn-thesis from a trace amount of Au^(3+).Thus,the required Au^(3+)ions concentration was reduced by one or two orders of magnitude compared with conventional methods of AuNPs *** work devel-oped an AuNPs size regulation technology via engineering eCell’s EET with synthetic biology methods,providing a feasible approach to synthesize AuNPs with controllable size from trace level of gold ions.

关键词： Au nanoparticles Exoelectrogenic cell(e-Cell) Shewanella Synthesis biology Extracellular electron transfer Reduced graphene oxide aerogel

Gas-sensing properties of nanocomplex metal oxide

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Progress in Natural science:materials International 2005年第7期15卷 669-672页

作者： CHEN Liangyuan, HE Zhusheng, YAN Tao, BAI Shouli, CHEN Aifan and LIU Chung Chiun ( Electronics Design Center, Case Western Reserve university, Cleveland, OH 44106, USA Department of Chemistry and chemical engineering, Baoji university of Arts and science, Baoji 721007, china college of science, beijing university of chemical technology, beijing 100029, china) Electronics Design Center Case Western Reserve University Cleveland 01-I 44106 USA. Department of Chemistry and chemical engineering Baoji University of Arts and Science Baoji 721007 China. college of science Beijing University of Chemical Technology Beijing 100029 China

The development of CuO/CeO2 nanocomposites as the sensing material of semiconductor gas sensors is reported. CuO/CeO2 nanocomplex oxide is prepared by modified sol-gel method that uses copper nitrate, cerium nitrate and ethylene glycol as precursors. The optimized synthesis parameters and processing condition have been established. The particle size and distribution, phase morphology, specific surface, electronic states of atoms and gas sensing properties have been systematically characterized by Transmission Electron Microscope (TEM), Brunauer Emmett Teller (BET), X-ray diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS) and gas sensitivity measurement. The results show that the sensor sensitivity depends on particle size, Cu/Ce cation ratio and calcination temperature. The effects of calcinations temperature and CuO loading on the gas sensitivity are also examined. The optimum calcination temperature and the CuO content for the highest sensitivity are 600 ℃and 12% , respectively. The combination of excellent thermal stability and tunable sensing properties through careful control of the processing parameters and selection of material composition gives rise to novel nanocomposites attractive to the sensitive and selective detection of a variety of toxic and combustible gases.

关键词： copper oxide cerium oxide nanocomposite CO gas sensitivity.

Synthesis and magnetic properties of CdS/α-Fe_2O_3 hierarchical nanostructures

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science china(Physics,Mechanics & Astronomy) 2009年第7期52卷 997-1002页

作者： CHEN yuJin1,2,3, SHI XiaoLing1, CAO MaoSheng1 & ZHU ChunLing4 1 School of materials science and engineering, beijing Institute of technology, beijing 100081, china 2 Micro-Nano Technologies Research Center, Hunan university, Changsha 410082, china 3 college of science, Harbin engineering university, Harbin 150001, china 4 college of material science and chemical engineering, Harbin engineering university, Harbin 150001, china 1. School of materials science and engineering Beijing Institute of Technology Beijing 100081 China 2. Micro-Nano Technologies Research Center Hunan University Changsha 410082 China 3. college of science Harbin Engineering University Harbin 150001 China 4. college of material science and chemical engineering Harbin Engineering University Harbin 150001 China

CdS/α-Fe2O3 hierarchical nanostructures, where the CdS nanorods grow irregularly on the side surface of α-Fe2O3 nanorods, were synthesized via a three-step process. The diameters and lengths of CdS nanorods can be tuned by changing the ethylenediamine (EDA) and Cd ion concentrations. The magnetic investigations by superconducting quantum interference device indicate that the hierarchical nanostructures have an Morin transition at lower temperature (230 K) than that of the single bulk α-Fe2O3 materials (263 K). Importantly, the hierarchical nanostructures exhibit weakly ferromagnetic characteristics at 300 K. A sharp peak assigned to the surface trap induced emission are observed in room temperature PL spectra. Combining with the optoelectronic properties of CdS, the CdS/ α-Fe2O3 hierarchical nanostructures may be used as multi-functional materials for optoelectronic and magnetic devices.

关键词： α-Fe2O3 CdS hierarchical nanostructures magnetic properties

Analysis of variance for testing method of cement in determination of strength

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Progress in Natural science:materials International 2011年第4期21卷 341-346页

作者： Hong HUANG,Xiao-dong SHEN State Key Laboratory of materials-Oriented chemical engineering,college of material science and engineering, Nanjing university of technology,Nanjing 210009,china State Key Laboratory of materials-Oriented chemical engineering College of Material Science and Engineering Nanjing University of Technology Nanjing 210009 China

The statistical tools such as descriptive statistics,full factorial design and analysis of source of variation were used to identify the potential factors that impact the validity of testing method for determining the strength of *** results showed that personal error impacted both accuracy and precision of test *** time associated with temperature fluctuation resulted in strength variation but did not impact the precision of test in all curing *** compactions did not impact the precision of test but resulted in the strength variation on 3 d and 28 d *** methods for the initial moist air curing significantly impacted the precision of testing method and resulted in the strength variation of cement on 1 d.

关键词： testing method of cement analysis of variance strength accuracy precision

Statistical study of cement additives with and without chloride on performance modification of Portland cement

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Progress in Natural science:materials International 2011年第3期21卷 246-253页

The effectiveness of cement additives with and without chloride on the fluidity and the strength development of Portland cement was compared by using statistical full factorial *** experimental results show that the cement additive containing CaCl2and Ca(NO3)2can enhance early strength of cement ***,Ca(NO3)2is less effective than CaCl2even if it is combined with other organic chemicals such as alkanolamine and *** significant difference is found between CaCl2and Ca(NO3)2influencing the fluidity and 28 d strength of *** fluidity is determined by saccharide and its interaction with *** 28 d strength enhancement is determined by *** fluidity as well as the mechanical performance of treated cement can be significantly improved by combining Ca(NO3)2with TIPA and saccharide.

关键词： Portland cement cement additive accelerator type fluidity strength development full factorial design

One-pot synthesis of crystalline SnO_2 nanoparticles and their low-temperature ethanol sensing characteristics

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science china(Physics,Mechanics & Astronomy) 2009年第10期52卷 1601-1605页

作者： CHEN yuJin1,2,3,ZHU ChunLing4,WANG LiJiao3 & WANG TaiHong2 1 School of materials science and engineering,beijing Institute of technology,beijing 100081,china 2 Micro-Nano Technologies Research Center,Hunan university,Changsha 410082,china 3 college of science,Harbin engineering university,Harbin 150001,china 4 college of material science and chemical engineering,Harbin engineering university,Harbin 150001,china School of materials science and engineering Beijing Institute of Technology Beijing 100081 China Micro-Nano Technologies Research Center Hunan University Changsha 410082 China college of science Harbin Engineering University Harbin 150001 China college of material science and chemical engineering Harbin Engineering University Harbin 150001 China

Crystalline SnO2 nanoparticles(NPs) with a diameter less than 6 nm are synthesized using potassium stannate trihydrate as the precursor in a basic *** synthesized NPs can detect ethanol at a ppm level even at 100℃.Furthermore,the NPs have good selectivity to *** excellent ethanol sensing performances are attributed to the small size effect according to the space-charge model.

关键词： SnO2 nanoparticles sensing characteristics

SYNTHESIS OF NOVEL THIOPHENEDIMETHYLENE BRIDGED HOMOBINUCLEAR METALLOCENES AND THEIR CATALYTIC PROPERTIES FOR ETHYLENE POLYMERIZATION

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Chinese Journal of Polymer science 2006年第1期24卷 21-27页

作者： Xi-jie Liu Jun-quan sun Hai-ying Zhang Xiao-hui Xiao and feng Lin Department of chemical engineering,college of material and chemical engineering,Zhejiang university,Hangzhou 310027,china Zhejiang Univ Coll Mat & Chem Engn Dept Chem Engn Hangzhou 310027 Peoples R China

By treating disodium（thiophenedimethylene）dicyclopentadienide C4H2S（CH2C5H4Na）2 with two equivalent of CpTiCl3 or CpZrC13 DME at 0℃ in THF, two new thiophenedimethylene bridged binuclear metallocenes [Cl2MC5H5][C5H4CH2C4H2SCH2C5H4][C5H5MCl2] （M = Ti 3, M = Zr 4） were synthesized in high yield and their structures were characterized by ^1H-NMR. These complexes were used as catalysts for ethylene polymerization in the presence of methylaluminoxane （MAO）. The effects of polymerization temperature, time, concentration of catalyst, molar ratio of MAO/Cat on polymerization were studied in detail. The catalytic activities of thiophenedimethylene bridged binuclear metallocene catalysts （3, 4） reached 2.44 × 10^5 g PE mol^-1 cat^-1· h^-1, 9.61 × 10^5 g PE mol^-1 · cat^-1· h^-1 respectively, which are higher than that of pheneyldimethylene bridged binuclear metallocene catalysts and much higher than that of corresponding mononuclear metallocenes （Cp2TiCl2 and Cp2ZrCl2）. The molecular weight distribution curves of polyethylenes produced by binuclear metallocene catalysts （3, 4） and by mononuclear metallocene catalyst have only single peak, but the former （MWD = 3.5-4.7） is obviously broader than the latter （MWD = 2.0-2.2）.

关键词： Binuclear metallocene Thiophenedimethylene bridged Ethylene polymerization.

New material of Coniopteris simplex from the Middle Jurassic of the Ordos Basin,Inner Mongolia,china and implications on its spatio-temporal distribution and paleogeography

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Journal of Palaeogeography 2024年第2期13卷 199-211页

作者： yun-feng Li Chang-Lu Zhang Fei Liang Xiao Tan Fan-Hao Gong Chun-Lin sun Tao Li yu-Ling Na Research Center of Paleontology and Stratigraphy Jilin UniversityChangchun 130026Jilin ProvinceChina college of Earth sciences Jilin UniversityChangchun 130061Jilin ProvinceChina college of Paleontology Shenyang Normal UniversityShenyang 110034Liaoning ProvinceChina Key Lab of Evolution of Past Life in NE Asia Ministry of Natural ResourcesShenyang Normal UniversityShenyang 110034Liaoning ProvinceChina Shenyang Center of Geological Survey China Geological SurveyShenyang 110034Liaoning ProvinceChina

Coniopteris simplex is a common component in many Jurassic ***,due to morphological variations in sterile fronds and incomplete preservation of reproductive organs,its classification has been controversial for a long ***,we present new material collected from the Middle Jurassic Yan’an Formation in the Ordos Basin,Inner *** new material reveals important morphological characters,including hemi-dimorphic fronds,two forms of sterile pinnae,short-stalked sori and sporangia on fertile fronds,annulus of sporangium composed of about 30 cells,in situ rounded triangular spores with protruded suture,and the lips of trilete laesura encircled by one or two rows of small *** on these observations,we emended the diagnosis of this common *** spatio-temporal distribution of Coniopteris simplex shows that the iconic species was restricted to the paleolatitudes ranging from 19.5°N to 48.9°N in the Northern Hemisphere during the Early—Late Jurassic,mainly distributed in the tropical to paratropical zones,and the paleolongitude ranging from 9.6°E to 129.3°E,which may be limited by the opening of the Viking Corridor and the splitting of the Central Atlantic Ocean.

关键词： Coniopteris simplex Yan'an Formation Middle Jurassic Inner Mongolia Paleogeography