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Graphene 2016年第3期5卷 143-154页

作者： m. S. Eluyemi m. A. Eleruja A. V. Adedeji B. Olofinjana O. Fasakin O. O. Akinwunmi O. O. Ilori A. T. Famojuro S. A. Ayinde E. O. B. Ajayi Department of Physics and Engineering Physics Obafemi Awolowo University Ile-Ife Nigeria Department of Chemistry and Physics Elizabeth City State University Elizabeth City NC USA Department of Electronics and Electrical Engineering Obafemi Awolowo University Ile-Ife Nigeria Department of Chemistry Obafemi Awolowo University Ile-Ife Nigeria

Graphene Oxide (GO) was chemically synthesized from Natural Flake Graphite (NFG). The GO was chemically reduced to Reduced Graphene Oxide (RGO) using hydrazine monohydrate. Thin films of GO and RGO were also deposited on sodalime glass substrate using spray pyrolysis technique (SPT). The samples were characterized using Fourier Transform Infrared (FTIR) spectroscopy, Scanning Electron microscopy (SEm) with Energy Dispersive X-Ray (EDS) facility attached to it, UV-Visible Spectrometry and Four-Point probe. The FTIR spectra showed the addition of oxygen functionality groups in GO while such groups was drastically reduced in RGO. SEm micrograph of GO thin film showed a porous sponge-like structure while the micrograph of RGO thin film showed evenly distributed and well connected graphene structure. The EDX spectrum of RGO showed that there was decrease in oxygen content and increase in carbon content of RGO when compared to GO. The optical analysis of the GO and RGO thin films gave a direct energy bandgap of 2.7 ev and 2.2 ev respectively. The value of sheet resistance of GO and RGO films was determined to be 22.9 × 106Ω/sq and 4.95 × 106Ω/sq respectively.

关键词： Graphite Graphene Graphene Oxide Thin Films Sheet Resistance

Physical Properties Study of Zn_(0.5)mn_(0.5−x)Li_(2x)Fe_(2)O_(4) Nanoparticle Series that Prepared by Co-Precipitation method

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Journal of materials Science and Chemical Engineering 2019年第11期7卷 15-21页

作者： N.A.Elthair Yousef A.Alsabah Eltayeb m.mustafa Abdelrahman A.Elbadawi Abdal Sakhi Suliman Ali A.S.marouf Department of Physics Faculty of Science and TechnologyAl Neelain UniversityKhartoumSudan Department of Physics Faculty of ScienceJazan UniversityJazanKingdom of Saudi Arabia Department of Physics Faculty of Education and Applied ScienceHajjah UniversityHajjahYemen Faculty of Basic Studies Future UniversityKhartoumSudan Institute of Laser Sudan University of Science and TechnologyKhartoumSudan

Co-precipitation is an important issue in chemical analysis, where it is often undesirable, but in some cases, it can be exploited. The Zn0.5mn0.5−xLi2xFe2O4 nanomaterials (x = 0.0, 0.1, 0.2, 0.3 and 0.4) was afforded by utilizing co-precipitation method. The structural and optical characteristics were analyzed for the samples employing X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR) and Ultraviolet-visible spectrophotometer (UV-Vis). XRD revealed that the structure of certain nanoparticles is a cubic spinel with space group (Fd-3m) and crystallite size in the scale 124 - 150 nm. Lattice parameter was determined to increments with Li+1 and that may occur due to the larger ionic radius of the Li1+ ion. FTIR spectroscopy confirmed the form of spinel ferrite and explicated the properties of absorption bands approximately 593, 1111, 1385, 1640, 2922 and 3430. The energy band gap was estimated for all samples with diverse ratios and was observed in the range of 2.58 - 2.52 ev.

关键词： Zn_(0.5)mn_(0.5-x)Li_(2x)Fe_(2)O_(4) Nano Ferrites XRD UV.vis FTIR Co-Precipitation Spinel Structure Ferrite Nanoparticles Optical Properties

Influenced of Cu2+Doped on Structural, morphological and Optical Properties of Zn-mg-Fe2O4Ferrite Prepared by Sol-Gel method

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Advances in Nanoparticles 2020年第2期9卷 49-58页

作者： Badawi m. Ali Yousef A. Alsabah mohamed A. Siddig Abdelrahman A. Elbadawi Abdalrawf I. Ahmed Abdulmajid A. mirghni Department of Physics Faculty of Science and Technology Al Neelain University Khartoum Sudan Research Chair in Laser Diagnosis of Cancers College of Science King Saud University Riyadh Kingdom of Saudi Arabia Department of Physics Faculty of Education and Applied Science Hajjah University Hajjah Yemen Department of Physics Faculty of Science Albaha University Albaha Kingdom of Saudi Arabia Faculty of Basic Studies Future University Khartoum Sudan Department of Physics Faculty of Education Al Fashir University Al Fashir Sudan

The Zn0.5Cuxmg0.5-xFe2O4 (where x = 0.0, 0.1, 0.2, 0.3 and 0.4) was prepared by sol-gel route and characterized in detail in terms of their structural, morphological, elemental and optical properties as a function of Cu concentration. X-ray diffractometer (XRD) results confirmed the formation of cubic spinel-type structure with average crystallized size in the range of 30.56 to 40.58 nm. Lattice parameter was found to decrease with Cu concentration due to the smaller ionic radius of Cu2+ ion. The HR-SEm images show morphology of the samples as prismatic shaped particles in agglomeration. The elemental dispersive X-ray Spectroscopy (EDX) confirmed the elemental composition of the as-prepared spinel ferrite material with respect to the initial concentration of the synthetic composition used for the material. The Fourier transform infrared (FTIR) spectroscopy confirmed the formation of spinel ferrite and showed the characteristics absorption bands around 463, 618, 876, 1116, 1442, 1622 and 2911 cm-1. The energy band gap was calculated for the samples were found to be in the range of 4.87 to 5.30 ev.

关键词： FTIR Nano Ferrite SEm UV-Vis XRD Zn-mg-Fe2O4 Ferrite

Determination of Neutron Fluxes and Spectrum Shaping Factors in Irradiation Sites of Ghana’S miniature Neutron Source Reactor (mnsr) by Activation method After Compensation of Loss of Excess Reactivty

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World Journal of Nuclear Science and Technology 2011年第2期1卷 50-56页

作者： R.B.m. Sogbadji B.J.B. Nyarko E.H.K. Akaho R. G. Abrefah Ghana Atomic Energy Commission National Nuclear Research Institute P.O. Box LG80 Legon Ghana

Accurate neutron flux values in irradiation channels of research reactors are very essential to their usage. The total neutron flux of the Ghana Research Reactor-1(GHARR-1) was measured after a beryllium reflector was added to its shim to compensate for excess reactivity loss. The thermal, epithermal and fast neutron fluxes were determined by the method of foil activation. The experimental samples with and without a cadmium cover of 1-mm thickness were irradiated in the isotropic neutron field of the irradiation sites of Ghana Research Reactor-1 facility. The induced activities in the sample were measured by gamma ray spectrometry with a high purity germanium detector. The necessary correction for gamma attenuation, thermal neutrons and resonance neutron self-shielding effects were taken into account during the experimental analysis. By defining cadmium cutoff energy of 0.55ev, Al-0.1% Au wires of negligible thickness were irradiated at 3kW to determine the neutron fluxes of two irradiation channels, outer channel 7 and inner channel 2 whose Neutron Shaping Factor (α) were found to be (0.037 ± 0.001) and (–0.961 ± 0.034). The neutron flux ratios at the inner irradiation site 2 were found to be, (25.308 ± 3.201) for thermal to epithermal neutrons flux, (0.179 ± 0.021) for epithermal to fast neutrons flux and (4.528 ± 0.524) for thermal to fast neutrons flux, in the outer irradiation site 7, the neutron flux ratios were found to be, (40.865 ± 3.622) for thermal to epithermal neutrons flux, (0.286 ± 0.025) for epithermal to fast neutrons flux and (11.680 ± 1.030) for thermal to fast neutrons flux.

关键词： Fluence Rate Foil Activation Neutron Self-Shielding Flux Ratio

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CdIn2Se4单晶的光致发光

哈尔滨工业大学学报 1982年第3期 1-12页

作者：高元恺 E.Grilli m.Guzzi 哈尔滨工业大学物理教研室米兰大学物理系

本文叙述了在2°K—185°K 的温度范围内,对化学输运法生长的单晶所测量的CdIn;Se;光致发光谱和发光激发谱的结果。在高于83°K 的温度下,发光谱是由一个高斯分布形状的带组成（我们称它为带Ⅰ）,在85°K 下,这个带的中心位于1.2ev 处;... 详细信息

本文叙述了在2°K—185°K 的温度范围内,对化学输运法生长的单晶所测量的CdIn;Se;光致发光谱和发光激发谱的结果。在高于83°K 的温度下,发光谱是由一个高斯分布形状的带组成（我们称它为带Ⅰ）,在85°K 下,这个带的中心位于1.2ev 处;它的半宽度是0.4ev。在低于85°K的温度下,在较高能量（1.40ev）处,出现另一个发光带（我们称它为带Ⅱ）。当激发强度增加时,发光带的最大值朝较高能量方向移动。激发谱不显示任何低于带隙能量的结构。分析我们的试验结果并同已发表的关于CdIn;Se;发光与光电导的工作比较,我们提出了在此种晶体带隙中的能级图和光激发载流子复合过程的模型。我们把带Ⅰ归因于在分布陷阱中的电子与受主能级上的空穴辐射复合,这个能级位于价带上0.14ev 处;带Ⅱ是由于电子从施主能级到价带的跃迁,施主能级位于导带底0.19ev 处。温度猝灭和发光与激发强度间的亚线性关系表明在带隙内应存在一个非辐射的复合中心。

关键词：光致发光激发谱能级电子轻子复合过程 CdIn2Se4 发光带发光谱晶形单晶

Characterization and Photocatalytic Efficiency of Palladium Doped-TiO2Nanoparticles

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Advances in Nanoparticles 2013年第4期2卷 372-377页

作者： Ahmed A. Abd El-Rady mahmmoud S. Abd El-Sadek mohamed m. El-Sayed Breky Fawzy H. Assaf Chemistry Department Faculty of Science South Valley University Qena Egypt Nanomaterials Lab Physics Department Faculty of Science South Valley University Qena Egypt

The effect of modification of TiO2 with different palladium concentrations on its characteristics and photocatalytic efficiency was studied. Photo catalysts were prepared by the sol-gel method and were characterized by different techniques. A uniform distribution of palladium through the TiO2 matrix was observed. The X-ray diffraction patterns of the pure and palladium doped TiO2 were found to be quiet similar and the average particle size was not significantly changed. As a result of palladium doping, the UV-Vis analysis showed a red shift in the onset of wavelength of absorbance and the band gap was changed from 3.39 to 3.06 ev for the 0.3 wt% Pd/TiO2 sample. Photo catalytic removal study of formic acid showed that the 0.3 wt% palladium doped photocatalyst exhibits the highest efficiency among the different palladium doped photocatalysts using sun light as the radiation source.

关键词： TiO2 Nanoparticles Sol-Gel Process Thermal Analysis Photocatalyst and Formic Acid

磷铊铟(In TlP)—推荐的一种红外探测器材料

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红外 1995年第10期16卷 13-17页

作者： m.Van Schilfgaarde 高国龙美国SRI国际公司

本文认为In_(1-x)Tl_xP是一种有前途的红外探测器材料。用局部密度-函数理论研究了一些主要的光学特性和结构特性。估计x=0.67的In_(1-x)Tl_xP和x=0.15的In_(1-x)Tl_xAs均具有0.1ev的带隙。它们的结合能均比InSb的大,而且发现,对于所有... 详细信息

本文认为In_(1-x)Tl_xP是一种有前途的红外探测器材料。用局部密度-函数理论研究了一些主要的光学特性和结构特性。估计x=0.67的In_(1-x)Tl_xP和x=0.15的In_(1-x)Tl_xAs均具有0.1ev的带隙。它们的结合能均比InSb的大,而且发现,对于所有的x,它们均能形成稳定的闪锌矿合金。In_(1-x)Tl_xP在晶格方面几乎与InP相匹配,而且具有集成探测器列阵和读出电路的潜在可能性。

关键词：红外探测器闪锌矿结构特性化合物读出集成电路焦平面列阵晶格常数带隙单片集成电子迁移率

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关于GaAs中硼注入的补偿机理

微纳电子技术 1984年第2期 53-54页

作者： C.m.martin 李炳辉

本文指出两种不同的补偿机理是引起深硼注入后观测到的载流子移出的原因:1)注入损伤,它主要引进导带下约0.55ev处的一个深能级窄带并且可在500℃左右温度下退火消除;2)形成硼施主络合物,可用它解释S70℃退火后仍观测到的载流子移出效应。

关键词：深能级硼注入载流子移出电子能态补偿机理 GaAs

电子入射氮原子的近域值双电离中电子关联分析(英文)

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ImP & HIRFL Annual Report 2006年 105-106页

作者：曹士娉 A.Dorn m.Dürr max-Planck-Institute for Nuclear Physics Saupfercheckweg 1 HeidelbergGermany. max-Planck-lnstitute for Nuclear Physics Saupfercheckweg 1 HeidelbergGermany.

The experiment on near threshold double ionization of helium by 106 ev electron impact was per- formed with reaction microscope in mPI-K: e+He→3e+He2+(1) The momenta of those three particles after double ionization were obtained by measuring their flight time and two dimensional *** electron detector of the setup has a hole in its center,which re- sults in the special structure shown in Fig.1a).Fig 1a)shows the two dimensional momentum distribu-

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Electron momentum Spectroscopy of metal and metal Oxide Thin Films

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Electron Momentum Spectroscopy of Metal and Metal Oxide Thin...