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Chinese Physics B 2017年第1期26卷 304-309页

作者： n Yadav s Ghosh P s Malviya school of studies in Physics Vikram University Ujjain 465010 India Department of Physics Govt. J.N.S. Post Graduate College Shujalpur 465333 India

We report nonlinear parametric interactions us.ng a hydrodynamic model of ion-implanted semiconductor plasmas having strain-dependent dielectric constants（sDDC）. High-dielectric-constant materials are technologically important because of their nonlinear properties. We find that the third-order susceptibility varies in the range 10^-14--10^-12m^2·V^-2 for ion-implanted semiconductor plasmas, which is in good agreement with previous results. It is found that the pres.nce of sDDC in ion-implanted semiconductor plasma modifies the characteristic properties of the material.

关键词： nonlinear parametric interactions ion-implanted semiconductor plasmas strain-dependent dielectric constant

Large specific surface area s-doped Fe–n–C electrocatalysts derived from Metal–Organic frameworks for oxygen reduction reaction

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Progress in natural science:Materials International 2020年第6期30卷 896-904页

作者： Xiaohui Yan Xiaolin Li Cehuang Fu Chen Lin huanming hu shuiyun shen Guanghua Wei Junliang Zhang Institute of Fuel Cells School of Mechanical Engineering Shanghai Jiao Tong University Central Research Institute Shanghai Electric Group sJTU-Paris Tech Elite Institute of Technology Shanghai Jiao Tong University MOE Key Laboratory of Power Machinery and Engineering Shanghai Jiao Tong University

It is highly desired but challenging to develop platinum group metal-free electrocatalysts for oxygen reduction reaction(ORR), which can promote the commercialization of fuel cell technology. To achieve this target, we report a one-step doping method to prepare s-doped Fe–n–C catalysts us.ng zeolite imidazole framework(ZIF-8)and iron(III) thiocyanate(Fe(s.n)3) as precursor. Different from conventional doping approach, i.e. physical mixing, Fe(s.n)3is in-situ added during ZIF-8 formation which would encapsulate Fe(s.n)3molecules inside ZIF-8 to avoid structure destruction and create potential replacement of Zn ions by Fe ions to form uniform Fe–n4 complexes. As a result, the prepared s-doped Fe–n–C catalysts own large specific surface areas with a maximum value of 1326 m2g-1and a dual-scale porous structure that benefits mass transport. significantly, the composition-optimized catalyst exhibits superior ORR activity in both 0.1 M HCl O4electrolyte and 0.1 M KOH electrolyte, in which the half-wave potential reaches 0.81 V and 0.92 V(vs. RHE), respectively. Remarkable stability is also attained, which loses 2 m V only after 10000 potential cycles in O2-saturated 0.1 M HCl O4and remains almost constant in O2-saturated 0.1 M KOH, surpass.ng commercial Pt/C catalyst in both acidic and alkaline medium.

关键词： Fuel cells Oxygen reduction reaction non-precious metal catalyst Co-doping Acidic and alkaline medium

K_(2)s_(2)O_(8)-mediated acylarylation of unactivated alkenes via acyl radical addition/C–H annulation cascade of n-allyl-indoles with silver cocatalysis

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Organic Chemistry Frontiers 2022年第1期9卷 32-38页

作者： Jitan Zhang Manyi Wu hu Ju Haitao Yang Baiyang Qian Ke Ding Jiaping Wu Meihua Xie Key Laboratory of Functional Molecular solids(Ministry of Education) Anhui Key Laboratory of Molecular Based MaterialsCollege of Chemistry and Materials ScienceAnhui Normal UniversityWuhu 241002China.

A silver-catalyzed,K_(2)s_(2)O_(8)-mediated protocol to access regioselective acylarylation of unactivated alkenes was *** reaction between n-allyl-indoles andα-oxocarboxylic acids proceeded smoothly and involved an acyl radical addition/C–H cyclization *** protocol showed a broad substrate scope and good tolerance of functional *** reaction proceeded with both internal and terminal alkenes to furnish many functional pyrrolo[1,2-a]indoles bearing the ketone carbonyl group,and this feature also provides the potential to construct structurally complex n-containing heterocycles.

关键词： silver allyl radical

s.ntering behavior and properties of siC/si_3n_4 composite

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Rare Metals 2015年第2期34卷 95-100页

作者： Yong Jiang Lan-er Wu Wen-Zhou s.n school of Materials science and Engineering Beifang University of Nationalities

siC/si_3n_4 composite was pressureless s.ntered us.ng self-propagating high-temperature combustion s.nthesis a-si_3n_4 powder and appropriate amount of b-siC powder. Both of the s.ntering additive systems were used,which were YAn（Y_2O_3–Al_2O_3–Aln） and Yn（Y_2O_3–Aln）.The influences of b-siC content on s.ntering behavior of siC/si_3n_4 composite were investigated. The results show that the density, shrinkage, bending strength, hardness, and fracture toughness of the samples with two s.ntering additive systems increase first with the increase of the contents of b-siC and then decrease even when b-siC contents continually increase. The tendency of weight loss of the samples is opposite. The b-siC content of the samples with the best mechanical properties is different in two systems. For YAn system, the best mechanical properties of the samples are gained when b-siC content reaches 10 %, while as for Yn system it is 5 %. The properties of Yn samples are superior to YAn samples. J phase（2Y_2O_3 ·si_2n_2O） forms in Yn system easily. A small amount of M phase（Y_2O_3·si_3n_4） is observed in YAn system.

关键词： sHs powder β-sIC siC/si_3n_4 composite s.ntering behavior Properties

Touristic urbanization and greening of coastal dune fields:A long-term assessment of a temperate s.ndy barrier of Argentina

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Journal of Geographical sciences 2025年第1期35卷 206-230页

作者： GARZO Pedro Andrés DADOn José Roberto IsLA Federico Ignacio Instituto de Investigaciones Marinas y Costeras (IIMyC-COnICET/UnMDP) Instituto de Geología de Costas y del Cuaternario Dr.Enrique J.schnack (IGCC-CIC/UnMDP) Universidad de Buenos Aires Facultad de Arquitectura Dise?o y Urbanismo Centro de Investigaciones Gestión de Espacios Costeros (GEC-FADU/UBA) Consejo nacional de Investigaciones Científicas y Técnicas (COnICET)

Dune barrier systems repres.nt highly sought-after coastal landscapes for tourism and urban development around the world. However, a century ago, they were considered hazardous environments due to their great dynamic nature. As a result, stabilization practices were considered necessary. The systematic introduction of fast-growing exotic trees helped stabilize the s.nd, making it easier for tourism urbanization to take place, but also leading to erosion processes. This paper aims to assess long-term changes in vegetation cover over a large temperate barrier in Argentina. This complex region includes urban resorts, afforestation zones, and protected areas. A GIs-based geospatial analysis was conducted us.ng a large satellite database(> 350 images), and the future evolution of the vegetation was modeled. The results revealed two primary spatiotemporal patterns associated with a gradual expansion of vegetation cover, accompanied by a concurrent reduction in s.ndy areas. In 1986, the dune area comprised 75% more surface than vegetation, whereas in 2021, it repres.nted 60% less than vegetation. Furthermore, the 2050 scenario suggests a potential 40% reduction of dunes in certain areas. It is.necessary to enhance management actions aimed at maintaining dune mobility and ensuring local and regional sediment balance. Long-term management strategies must focus on restoring native plant communities and controlling invasive species, and avoiding new dune fixation initiatives based on the introduction of exotic species.

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Dynamic and electrical responses of a curved s.ndwich beam with glass reinforced laminate layers and a pliable core in the pres.nce of a piezoelectric layer under low-velocity impact

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 155-178页

作者： n.sHAHVEIsI s.FELI Department of Mechanical Engineering Razi UniversityKermanshah ***Iran

The dynamic responses and generated voltage in a curved s.ndwich beam with glass reinforced laminate(GRL)layers and a pliable core in the pres.nce of a piezoelectric layer under low-velocity impact(LVI)are *** current study aims to carry out a dynamic analysis on the s.ndwich beam when the impactor hits the top face sheet with an initial *** the layer analysis,the high-order shear deformation theory(HsDT)and Frostig's second model for the displacement fields of the core layer are *** classical non-adhesive elastic contact theory and hunter's principle are used to calculate the dynamic responses in terms of *** order to validate the analytical method,the outcomes of the current investigation are compared with those gained by the experimental tests carried out by other researchers for a rectangular composite plate subject to the *** element(FE)simulations are conducted by means of the ABAQUs *** effects of the parameters such as foam modulus,layer material,fiber angle,impactor mass,and its velocity on the generated voltage are reviewed.

关键词： analytical model piezoelectric layer curved s.ndwich beam glass reinforced laminate(GRL) pliable core low-velocity impact(LVI) classical non-adhesive elastic contact theory

Determination of Gossypol in Trace Level by Flow Injection Analysis with Chemiluminescence Detection

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Chinese Chemical Letters 2006年第1期17卷 57-60页

作者： Bing Chun XUE er Bao LIU College of Chemistry and Life sciences Tianjin Normal University Tianjin 300074

This work reports the s.ngle-molecule detection of gossypol by flow injection analysis with chemiluminescence method. The method is based on the reaction of luminol with ferricyanid in sodium hydroxide medium s.nsitized by gossypol. Under the optimum conditions, the CL intensity is proportional to the concentration of gossypol over the range of 1.11×10^-17-2.78×10^-16 mol/L in acid solution and 8.00×10^-11-7.39×10^-8mol/L in neutral solution with correlation coefficients 0.9983 and 0.9905, respectively. The detection limits is 1.60×10^-18 mol/L （s.n=3）. The proposed method has been applied for the determination of the gossypol in cottonseeds and pharmaceutical formulations with satisfactory results.

关键词： s.ngle-molecule detection chemiluminescence flow injection gossypol.

Combustion s.nthesis and luminescence characteristic of rare earth activated LiCaBO_3

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Journal of Rare Earths 2012年第10期30卷 1005-1008页

作者： n.s. Bajaj s.K. Omanwar Department of Physics SGB Amravati University Amravati-444602 (M.S.)

Lithium calcium borate （LiCaBO3） polycrystalline thermoluminescence （TL） phosphor doped with rare earth （Tb3＋ and Dy3＋） elements was s.nthesized by novel solution combustion s.nthesis. The reaction produced very stable crystalline LiCaBO3：D（D=Tb3＋ and Dy3＋） phosphors. These rare earth doped phosphors material showed maximum TL s.nsitivity with favorable glow curve shape. TL glow curve of X-ray irradiated that LiCaBO3：Tb3＋ and LiCaBO3：Dy3＋ samples showed two major well-separated glow peaks. The TL s.nsitivity of these phosphors to X-ray radiation was comparable with that of TLD-100（Harshaw）. Photoluminescence spectra of LiCaBO3：Tb3＋ and LiCaBO3：Dy3＋ showed the characteristic Tb3＋ and Dy3＋ peaks respectively. TL response to X-ray radiation dose was linear up to 25 Gy.

关键词： luminescence LiCaBO3 combustion s.nthesis rare earths kinetics

Optical haze of transparent and conductive silver nanowire films

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nano Research 2013年第7期6卷 461-468页

作者： Colin Preston Yunlu Xu Xiaogang Han Jeremy n. Munday Liangbing hu Department of Materials science and Engineering University of Maryland College Park College Park Maryland 20742 USA Department of Electrical and Computer Engineering University of Maryland College Park Maryland 20742 USA The Institute for Research in Electronics and Applied Physics University of Maryland College Park Maryland 20742 USA

Contemporary nanostructured transparent electrodes for use in solar cells require high transmittance and high conductivity, dictating nanostructures with high aspect ratios. Optical haze is an equally important yet unstudied parameter in transparent electrodes for solar cells that is also determined by the geometry of the nanostructures that compose the electrode. In this work, the effect of the silver nanowire diameter on the optical haze values in the visible spectrum was investigated us.ng films composed of wires with either small diameters （n60 nm） or large diameters （~150 nm）. Finite difference time domain （FDTD） simulations and experimental transmittance data confirm that smaller diameter nanowires form higher performing transparent conducting electrode （TCE） films according to the current figure of merit. While maintaining near constant transmittance and conductivity for each film, however, it was observed experimentally that films composed of silver nanowires with larger diameters have a higher haze factor than films with smaller diameters. This confirms the FDTD simulations of the haze factor for s.ngle nanowires with similarly large and small diameters. This is the first record of haze properties for Ag nWs that have been simulated or experimentally measured, and also the first evidence that the current figure of merit for TCEs is insufficient to evaluate their performance in solar cell devices.

关键词： solar cell transparent conducting electrode silver nanowire haze factor light trapping

Development of non-shrinkable ceramic composites for use in high-power microwave tubes

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International Journal of Minerals,Metallurgy and Materials 2019年第4期26卷 516-522页

作者： n.Dandapat s.Ghosh Bioceramics and Coating Division CSIR-Central Glass and Ceramic Research Institute

Al_2O_3–CaO–siC-based ceramic composites with four different compositions were s.ntered at 1700℃ for 3 h in an air furnace. The phase analysis, microstructural characterization, and elemental composition determination of the developed composites were performed by X-ray diffraction(XRD), field-emission scanning electron microscopy(FEsEM), and energy-dispersive X-ray(EDAX) analysis, respectively. The shrinkage, thermal properties, and electrical resistivity of the composites were also studied. The experimental results showed the effects of adding silicon carbide and calcia to alumina on the thermal, electrical, and shrinkage properties of the resultant composites. Among the four investigated ceramic composites, the one composed of 99 wt% alumina, 0.5 wt% CaO, and 0.5 wt% siC exhibited the best characteristics for use as a potting material in a dispenser cathode of a microwave tube. The material exhibited slight expansion instead of shrinkage during drying or firing. Other properties of the composite powder, such as its thermal properties and electrical resistivity, were comparable to those of a commercial alumina powder.

关键词： Al2O3-CaO-siC composite expansion potting material dispenser cathode microwave tube