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Alternating current characterization of nano-Pt(Ⅱ)octaethylporphyrin(PtOEP) thin film as a new organic semiconductor

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Chinese Physics B 2016年第6期25卷 426-432页

作者： m Dongol m m El-Nahass A El-Denglawey A A Abuelwafa t Soga Nano and thin Film Laboratory Physics DepartmentFaculty of ScienceSouth Valley University Physics Department Faculty of EducationAin Shams University Physics Department Faculty of Applied Medical ScienceTaif University Department of Frontier materials Nagoya Institute of Technology

Alternating current（AC） conductivity and dielectric properties of thermally evaporated Au/Pt OEP/Au thin films are investigated each as a function of temperature（303 K–473 K） and frequency（50 Hz–5 mHz）.the frequency dependence of AC conductivity follows the Jonscher universal dynamic *** AC-activation energies are determined at different *** is found that the correlated barrier hopping（CBH） model is the dominant conduction *** variation of the frequency exponent s with temperature is analyzed in terms of the CBH *** barrier height Wm,hopping distance Rω,and the density of localized states N（EF） are valued at different *** constant ε1（ω,t） and dielectric loss ε2（ω,t） are discussed in terms of the dielectric polarization *** dielectric modulus shows the non-Debye relaxation in the *** extracted relaxation time by using the imaginary part of modulus（m’’）is found to follow the Arrhenius law.

关键词： PtOEP thin films AC conductivity dielectric constants organic semiconductors solar cell nano materials

Compton profiles of NiO and tiO_2 obtained from first principles GWA spectral function

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Chinese Physics B 2016年第6期25卷 407-415页

作者： S m Khidzir m F m Halid W A t Wan Abdullah Department of Physics Universiti of Malaya

In this work,we first use momentum density studies to understand strongly correlated electron behavior,which is typically seen in transition metal *** observe that correlated electron behavior as seen in bulk NiO is due to the Fermi break located in the middle of overlapping spectral functions obtained from a GW（G is Green’s function and W is the screened Coulomb interaction） approximation（GWA） calculation while in the case of tiO2 we can see that the origin of the constant momentum distribution in lower momenta is due to a pile up of spectra before the Fermi *** observations are then used to compare our calculated Compton profiles with previous experimental studies of Fukamachi and *** calculations for NiO are observed to follow the same trend as the experimental profile but it is seen to have a wide difference in the case of tiO2 before the Fermi *** ground state momentum densities differ significantly from the quasiparticle momentum density,thus stressing the importance of the quasiparticle wave function as the input for the study of charge density and the electron localization *** we perform a calculation of the quasiparticle renormalization function,giving a quantitative description of the discontinuity of the GWA momentum density.

关键词： elastic and Compton scattering density functional theory local density approximation gradient and other corrections elements oxides nitrides borides carbides chalcogenides

theoretical study of differential cross sections for the ionization of helium by fast proton impact

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Chinese Physics B 2024年第11期33卷 255-264页

作者： m mondal B mandal t mistry D Jana m Purkait Department of Physics Ramakrishna Mission Residential CollegeNarendrapurKolkata-700103India

We present the angular distribution of the ejected electron for single ionization of He by fast proton impact.A fourbody formalism of the three-Coulomb wave is applied to calculate the triple differential cross sections at several impact energies in the scattering,perpendicular and azimuthal ***,the three-body formalism of three-Coulomb,two-Coulomb and first Born approximation models has also been used to study the many-body effect on electron emission and the validity of the *** the three-Coulomb wave model,the final state wave function incorporates distortion due to the three-body mutual Coulombic *** this formalism,we use an uncorrelated and correlated Born initial state,which consists of a plane wave for the incoming projectile times a two-electron bound state wavefunction of the helium atom representing the 1s2(1S)***,in the case of the three-body formalism,the initial state wavefunction consists of a long-range Coulomb distortion for the incoming projectile and one active electron of the He atom described by the Roothaan–Hartree–Fock *** structure with a single or two peaks with unequal intensity is observed in the angular distributions of the triple differential cross sections for the different kinematic *** addition,the influence of static electron correlations is investigated using different bound state wavefunctions for the ground state of the He *** the four-body formalism,the present computations are very fast by reducing a nine-dimensional integral to a two-dimensional real *** the simplicity and speed of the proposed quadrature,the comparison shows that the obtained results are in reasonable agreement with the experiment and are compatible with those of other theories.

关键词： ionization cross sections collision atoms ions

PV based water pumping system for agricultural irrigation

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Frontiers in Energy 2016年第3期10卷 319-328页

作者： t A BINSHAD K VIJAYAKUmAR m KALEESWARI Department of Electrical Engineering Malaviya National Institute of Technology Jaipur 302017 India Department of Electrical Engineering Poomima University Jaipur302017 India

this paper investigates the operation and analysis of the photovoltaic water pumping system in detail. Power electronic controllers were designed and developed for the water pumping system using a boost converter along with an inverter followed by an induction motor pump set. the proposed system could be employed in agricultural irrigation under any operating condition of varying natures of solar irradiances and temperatures. the configuration and implementation of the system were described in detail. Further, the detailed method of analysis and simulation characteristics of such PV water pumping system was also presented. With the concern of shortage of fossil fuel, global warming and energy security, the proposed PV based water pumping significant demand of electricity agricultural sector. system can meet the and serve for the

关键词： photovoltaic water pumping system power electronic controller solar irradiances and temperature

Regional tectonics, geology, magma chamber processes and mineralisation of the Jinchuan nickel-copper-PGE deposit, Gansu Province, China： A review

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Geoscience Frontiers 2016年第3期7卷 431-451页

作者： t.m. (mike) Porter Porter GeoConsultancy Pry Ltd. Linden Park 5065 SA Australia

the Jinchuan Ni-Cu-PGE deposit（〉500 mt @1.2%Ni,0.7%Cu,～0.4 g/t PGE）,one of the largest magmatic sulphide deposits in the world,is located within the westernmost terrane of the North China *** is hosted within the 6.5 km long,Neoproterozoic（～0.83 Ga） Jinchuan ultramafic intrusion,emplaced as a sill-like body into a Palaeoproterozoic suite of gneisses,migmatites,marbles and amphibolites,below an active intracratonic *** parental magma was high-mg basalt,generated through melting of subcrustal lithospheric mantle by a mantle plume during the initiation of Rodinia supercontinent *** lower Palaeozoic collision of the exotic Qilian Block with the breakup-related southern margin of the craton accreted a subduction complex,and emplaced voluminous granitic intrusions and foreland basin sequences within the craton,to as far north as *** the Cainozoic,allochthonous lower Palaeozoic rocks were thrust up to 300 km to the northeast over cratonic basement,to within 25 km of the Jinchuan *** Jinchuan ultramafic intrusion was injected into three interconnected sub-chambers,each containing a separate *** essentially comprises an olivine-orthopyroxene-chromite cumulate,with interstitial orthopyroxene,clinopyroxene,plagioclase and phlogopite,and is predominantly composed of lherzolite（～80%）,with an outer rim of olivine pyroxenite and cores of mineralised *** occurs as disseminated and net-textured sulphides,predominantly within the dunite,with lesser,PGE rich lenses,late massive sulphide accumulations,small copper rich pods and limited mineralised diopside skarn in wall rock *** principal ore minerals are pyrrhotite（the dominant sulphide）,pentlandite,chalcopyrite,cubanite,mackinawite and pyrite,with a variety of platinum group minerals and minor *** deposit underwent significant post-magmatic tremolite-actinolite,chlorite,serpentine and magnetite *** volume of thejinchuan intrusion accounts for 〈3%

关键词： Rodinia break-up rifting Plume related Deep staging chamber Olivine-orthopyroxene-chromite cumulate Net textured and disseminated sulphides Post-magmatic alteration

Passive wireless smart-skin sensor using RFID-based folded patch antennas

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International Journal of Smart and Nano materials 2011年第1期2卷 22-38页

作者： Xiaohua Yi terence Wu Yang wang Roberto t.Leon manos m.tentzeris Gabriel Lantz School of Civil and Environmental Engineering Georgia Institute of TechnologyAtlantaGA30332USA School of Electrical and Computer Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

Folded patch antennas were investigated for the development of low-cost and wireless smart-skin sensors that monitor the strain in metallic *** the patch antenna is under strain/deformation,its resonance frequency varies *** variation can be easily interrogated and recorded by a wireless *** patch antenna adopts a specially chosen substrate material with low dielectric attenuation,as well as an inexpensive off-the-shelf radiofrequency identification(RFID)chip for signal *** the RFID chip harvests electromagnetic power from the interrogation signal emitted by the reader,the patch antenna itself does not require other(internal)power sources and,thus,serves as a battery-less(passive)and wireless strain *** this preliminary investigation,a prototype folded patch antenna has been designed and *** testing results show strong linearity between the interrogated resonance frequency and the strain experienced by the *** experiments,the strain sensing resolution is demonstrated to be under 50με,and the wireless interrogation distance is shown to be over a few feet for this preliminary prototype.

关键词： passive wireless sensor folded patch antenna strain sensor smart skin RFID

the geology, structure and mineralisation of the Oyu tolgoi porphyry copper-gold-molybdenum deposits, mongolia： A review

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Geoscience Frontiers 2016年第3期7卷 375-407页

作者： t.m.(mike) Porter Porter CeoConsultancy Ply Ltd. Linden Park 5065 SA Australia

the Oyu tolgoi cluster of seven porphyry Cu-Au-mo deposits in southern mongolia,define a narrow,linear,12 km long,almost continuously mineralised trend,which contains in excess of 42 mt of Cu and1850 t of Au,and is among the largest high grade porphyry Cu-Au deposits in the *** deposits lie within the Gurvansayhan island-arc terrane,a fault bounded segment of the broader Silurian to Carboniferous Kazakh-mongol arc,located towards the southern margin of the Central Asian Orogenic Belt,a collage of magmatic arcs that were periodically active from the late Neoproterozoic to Permotriassic,extending from the Urals mountains to the Pacific *** at Oyu tolgoi is associated with multiple,overlapping,intrusions of late Devonian（～372 to 370 ma） quartzmonzodiorite intruding Devonian（or older） juvenile,probably intra-oceanic arc-related,basaltic lavas and lesser volcaniclastic rocks,unconformably overlain by late Devonian（～370 ma） basaltic to dacitic pyroclastic and volcano sedimentary *** quartz-monzodiorite intrusions range from earlymineral porphyritic dykes,to larger,linear,syn-,late- and post-mineral dykes and *** was deposited within syn-mineral quartz-monzodiorites,but is dominantly hosted by augite basalts and to a lesser degree by overlying dacitic pyroclastic *** ore deposition,an allochthonous plate of older Devonian（or pre-Devonian） rocks was overthrust and a post-ore biotite granodiorite intruded at～365 *** is characterised by varying,telescoped stages of intrusion and *** A-type quartz veined dykes were followed by Cu-Au mineralisation associated with potassic alteration,mainly K-feldspar in quartz-monzodiorite and biotite-magnetite in basaltic *** reflux of cooled,late-magmatic hydrothermal fluid resulted in intense quartz-sericite retrograde alteration in the upper parts of the main syn-mineral intrusions,and an equivalent chlorite-muscovite/illite-hematite assemblage in bas

关键词： tectonic setting Porphyry copper-gold-molybdenum deposit High sulphidation Geology Alteration Structure

Saturated coordinated control of multiple underactuated unmanned surface vehicles over a closed curve

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Science China(Information Sciences) 2017年第7期60卷 40-53页

作者： Lu LIU Dan wang Zhouhua PENG Hugh H.t.LIU School of marine Engineering Dalian Maritime University Department of Computer Science City University of Hong Kong Institute for Aerospace Studies University of Toronto

this paper presents a design method for saturated coordinated control of multiple underactuated unmanned surface vehicles(USVs) on a closed curve, holding a symmetric formation pattern. Each vehicle is subject to unknown sideslip, uncertain vehicle kinetics, and limited control torques. First, the course angle and surge velocity are considered as immediate signals to stabilize the along-track and cross-track path following errors. In the vehicle kinematics, a reduced-order extended state observer is utilized to compensate for the effect of the unknown sideslip. Next, a bounded neural network control law is constructed at the kinetic level with the aid of the a saturated function, a projection operator, and a dynamic surface design method. Finally, a parameter cyclic pursuit approach is presented to guarantee that the vehicles are evenly spaced over the closed curve for achieving a symmetric formation pattern. the input-to-state stability of the closed-loop system is analyzed via cascade theory. Comparative studies are given to show the effectiveness of the proposed method.

关键词： symmetric formation pattern parameter cyclic pursuit reduced-order extended state observer neural networks saturated control

microstructure and brazing mechanism of porous Si_3N_4/Invar joint brazed with Ag-Cu-ti/Cu/Ag-Cu multi-layered filler

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Journal of materials Science & technology 2018年第4期34卷 713-719页

作者： J.Zhang J.Y.Liu t.P.wang School of materials Science and Engineering Harbin Institute of Technology

Porous Si3N4 was brazed to Invar alloy in this study, and Ag-Cu-ti/Cu/Ag-Cu multi-layered filler was designed to inhibit the formation of Fe2ti and Ni3ti intermetallic compounds. the effects of the brazing temperature and the thickness of Cu interlayer on the microstructure and mechanical properties of brazed joints were investigated. the typical microstructure of the joint brazed with multi-layered filler was porous Si3N4/tiN ＋ ti5Si3/Ag-Cu eutectic[Cu[Ag-Cu eutectic/Cu-rich layer ＋ diffusion layer/Invar. When the brazing temperature increased, the reaction layer at the ceramic/filler interface grew thicker and the Cu interlayer turned thinner. As the thickness of Cu interlayer increased from 50 to 150 μm, the joint strength first increased and then decreased. In this research, the maximum shear strength （73 mPa） was obtained when being brazed at 1173 K with a 100 μm Cu interlayer applied in the filler, which was 55% higher than that brazed with single Ag-Cu-ti brazing alloy and had reached 86% of the ceramic. the release of residual stress and the barrier effect of Cu interlayer to inhibit the formation of Fe2ti and Ni3ti intermetallics played the major role in the improvement of joint strength.

关键词： Porous Si3N4 Invar alloy Brazing microstructure mechanical properties