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Effect of sodium modification on.m.crostructure and mechanical properties of thick-walled AlSi6Cu2.5 rheocast component

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Transactions of nonferrous metals Society of China 2010年第9期20卷 1643-1648页

作者： m.WESSn n.E.AnDE RSSOn O.GRAnATH School of Engineering Materials and Manufacturing-CastingJnkping University

The microstructure and tensile properties were investigated in a thick-walled section （approximately 45 mm×43 mm） of a rheocast component produced by the RheometalTm process. Due to the long solidification period of such components, it is expected that the A1-Si eutectic formed will be coarse. Therefore, sodium （na） was used as a modifying agent to reduce the coarseness of the eutectic. Tensile test bars were machined from three different sets of materials： 1） non.m.dified melt, 2） modified melt cast directly after na addition, and 3） modified melt cast 30 min after na addition. The alloy used was a secondary AlSi6Cu2.5 alloy （STEnAL Rheol）, specially developed for rheocasting. The material was studied in the as-cast condition as well as after a T6 heat treatment. The results show that the Al-Si eutectic is significantly refined by the na addition, even after a fading time of 30 min. However, it is observed that the na modification generally has a detrimental effect on the mechanical properties, despite the structure refin.m.nt. This is especially true in the T6 heat treated condition, where the yield strength is reduced by more than 30%. Some possible mechanisms for the degradation of mechanical performance are discussed.

关键词： rheocasting thick-walled component eutectic modification mechanical properties sodium Al alloys

Is Li-ESWT effective in diabetic patients with severe erectile dysfunction?

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Asian Journal of Andrology 2022年第5期24卷 521-524页

作者： müslüm Ergün Osman Akyüz Department of Urology School of MedicineAtlas UniversityIstanbul 34200Turkey

noninvasive low-intensity extracorporeal shockwave treatment(Li-ESWT)has been widely used to treat erection *** is no clear information regarding either the selection of patients for the treatment or the treatment *** this study,we aimed to investigate the efficacy of extracorporeal shockwave therapy in diabetic patients with severe erectile dysfunction(International Index of Erectile Function-5[IIEF-5]scores of 5 to 7).Sixty-three diabetes mellitus patients with erectile dysfunction having IIEF-5 scores of 5 to 7 and not showing a recovery of potency despite phosphodiesterase type 5 inhibitor therapy for the past 6 months were included in the *** patients were evaluated based on their IIEF-5 scores and Erection Hardness Scale *** IIEF-5 score(mean±standard deviation[s.d.])increased from 5.29±1.67 to 5.56±1.85,with a difference of 0.27±0.18(P>0.05).The Erection Hardness Scale scores(mean±s.d.),on the other hand,increased from 1.46±0.50 to 1.48±0.50,with a difference of 0.02±0(P>0.05).In conclusion,the response to phosphodiesterase type 5 inhibitors did not change after extracorporeal shockwave treatment in diabetes mellitus patients with severe erectile dysfunction(IIEF-5 scores of 5 to 7).

关键词： diabetes mellitus International Index of Erectile Function-5 score low-intensity extracorporeal shockwave treatment severe erectile dysfunction

Investigating the effect of entrance channel mass asymmetry on fusion reactions using the Skyrme energy density formalism

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nuclear Science and Techniques 2020年第9期31卷 45-52页

作者： m.m.Hosamani A.Vinayak n.m.Badiger Department of Studies in Physics Karnatak UniversityDharwad 580003India

In the present investigations,the fusion crosssections for the formation of 200Pb compound nucleus(Cn)using 16O+184 W,30Si+170Er,and 40Ar+160Gd nuclear reactions at energies above the Coulomb barrier were calculated to understand the effect of entrance channel mass asymmetry(α)on the fusion reactions;the Skyrme energy density formalism(SEDF)was used for this *** SEDF uses the Hartree-Fock-Bogolyubov(HFB)computational program with Skyrme forces such as Skm*,SLy4,and SLy5 to obtain the nucleus-nucleus potential parameters for the above *** the SEDF model with Skm*,SLy4,and SLy5 interaction forces,the theoretical fusion cross-sections were determined above the barrier energy and compared with the available experimental fusion *** results show a close agreement between the theoretical and experimental values for all selected systems at energies well above the ***,near the barrier energies,the theoretical values were observed to be higher than the experimental values.

关键词： Skyrme force Energy density formalism Hartree-Fock-Bogolyubov Thomas-Fermi model Coupled-channel calculation

Ultraviolet and visible upconversion luminescence of Tm(0.1)Yb(5):FOV oxyfluoride nanophase vitroceramics

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Science China(Physics,mechanics & Astron.m.) 2008年第12期51卷 1868-1876页

作者： n. SAWAnOBOI m. OHTSUKA Sumita Optical Glass Inc. Japan

The ultraviolet upconversion luminescence of Tm3+ ions sensitized by Yb3+ ions in oxyfluoride nanophase vitroceramics when excited by a 975 nm diode laser was studied. An ultraviolet upconversion luminescence line positioned at 363.6 nm was found. It was attributed to the fluorescence transition of 1D2→3H6 of Tm3+ ion. Sev- eral visible upconversion luminescence lines at 450.7 nm, (477.0 nm, 462.5 nm), 648.5 nm, (680.5 nm, 699.5 nm) and (777.2 nm, 800.7 nm) were also found, which result respectively from the fluorescence transitions of 1D2→3F4, 1G4→3H6, 1G4→3F4, 3F3→3H6 and 3H4→3H6 of Tm3+ ion. The careful measurement and analysis of the variation of upconversion luminescence intensity F as a function of the 975 nm pumping laser power P prove that the upconversion luminescence of 1D2 state is partly a five-photon upconversion luminescence, and the upconversion lumines- cence of 1G4 state and 3H4 state are respectively the three-photon and two-photon upconversion luminescence. The theoretical analysis suggested that the upcon- version.m.chanism of the 363.6 nm 1D2→3H6 upconversion luminescence is partly the cross energy transfer of {3H4(Tm3+)→3F4(Tm3+), 1G4(Tm3+)→1D2(Tm3+)} and {1G4(Tm3+)→3F4(Tm3+), 3H4(Tm3+)→1D2(Tm3+)} between Tm3+ ions. In addition, the upconversion luminescence of 1G4 and 3H4 state results respectively from the se- quential energy transfer {2F5/2(Yb3+)→2F7/2(Yb3+), 3H4(Tm3+)→1G4(Tm3+)} and {2F5/2(Yb3+) →2F7/2(Yb3+), 3F4(Tm3+)→3F2(Tm3+)} from Yb3+ ions to Tm3+ ions.

关键词： upconversion luminescence ultraviolet oxyfluoride nanophase vitroceramics saturation Tm3+ ion Yb3+ ion energy transfer

Parametric analysis of steel plated shear structures

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Journal of Central South University 2014年第5期21卷 2083-2090页

作者： m.Ghassemieh n.Heidari School of Civil Engineering University of Tehran

Due to outstanding ductility and high strength,the steel plate shear wall(SPSW)is recognized as a good lateral system for building structures; particularly as it interacts with earthquake resistant *** study aims to reveal the dyn.m.c and cyclic behavior of steel plated shear *** element method of analysis was implemented in order to simulate the behavior of such a wall *** determine the dyn.m.c behavior of un-stiffened plate shear wall,two different analytical models were *** post buckling strength of steel plate subjected to lateral loading was also *** story shear-drift diagrams of steel shear wall system were *** strength and ductility of the system obtained from the analysis were compared with those of steel shear wall tests reported *** pertinent parameters of the steel shear wall system such as plate thickness,column and beam stiffness and the plate aspect ratio were recognized and their effects were *** effect of stiffeners on the behavior of the SPSW was also investigated.

关键词： steel shear wall pushover analysis energy dissipation ductility post buckling behavior Strut element

Action.m.chanisms of Arbuscular mycorrhizal Fungi in Phosphorus Uptake by Capsicum annuum L.

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Pedosphere 2011年第4期21卷 502-511页

作者： m.SHARIF n.CLAASSEn Department of Soil and Environmental Sciences NWFP Agricultural University Department of Crop Sciences (Plant nutrition) Georg-August-University Gttingen

A pot experiment was conducted to investigate the action.m.chanisms phorus （P） uptake of Capsicum annuum L. in a sterilized fossil Oxisol of arbuscular mycorrhizal （Am） fungi in phos- Three P levels of 0, 10 and 200 mg kg-1 soil （P0, P10 and P200, respectively） without and with Am fungal inoculation were applied as Ca（H2PO4）2-H20. Shoot dry matter yields and shoot P uptake increased significantly （P 〉 0.05） by the inoculation of Am fungi at P0 and P10. Root length and P concentration in soil solution increased with the inoculation of Am fungi but the root：shoot ratio decreased or remained constant. Around 50% roots of inoculated plants were infected by Am and the external hyphae amounted to 20 m g^-1 soil at P10 and P200. The hyphae surface area of the infected root cylinder amounted to 11 and 2 cm^2 cm^-2 root at P0 and P10, respectively. The increased P uptake of inoculated plants was mainly because of an up to 5 times higher P influx of the infected root. model calculations showed that the root alone could not have achieved the measured P influx in both infected and non-infected roots. But the P influx for hyphae calculated by the model was even.m.ch higher than the measured one. The P uptake capacity of hyphae introduced in the model was too high. model calculations further showed that the depletion zone around roots or hyphae was very narrow. In the case of the root only 7% of the soil volume would contribute P to the plant, while in the case of hyphae it would be 100%. The results together with the model calculations showed that the increased P uptake of Am inoculated plants could be explained partly by the increased P concentration in the soil solution and by the increased P absorbing surface area coming from the external hyphae.

关键词： hyphae mechanistic model phosphorus influx root infection root morphology

A multi coding technique to reduce transition activity in VLSI circuits

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Journal of Semiconductors 2014年第2期35卷 131-136页

作者： n.Vithyalakshmi m.Rajaram Udaya School of Engineering Anna University

Advances in VLSI technology have enabled the implementation of complex digital circuits in a single chip, reducing system size and power consumption. In deep submicron low power CmOS VLSI design, the main cause of energy dissipation is charging and discharging of internal node capacitances due to transition activity. Transition activity is one of the major factors that also affect the dyn.m.c power dissipation. This paper proposes power reduction analyzed through algorithm and logic circuit levels. In algorithm level the key aspect of reducing power dissipation is by min.m.zing transition activity and is achieved by introducing a data coding technique. So a novel multi coding technique is introduced to improve the efficiency of transition activity up to 52.3% on the bus lines, which will automatically reduce the dyn.m.c power dissipation. In addition, 1 bit full adders are introduced in the Hamming distance estimator block, which reduces the device count. This coding method is implemented using Verilog HDL. The overall performance is analyzed by using modelsim and Xilinx Tools. In total 38.2% power saving capability is achieved compared to other existing methods.

关键词： CmOS VLSI Hamming distance power dissipation transition activity interconnect

An Alternative Approach to the Extraction of Structure Functions in Deep Inelastic e—p Scattering at 5 to 20 GeV

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Communications in Theoretical Physics 2003年第5期39卷 573-578页

作者： n.Ghahramany m.nouri DepartmentofPhysics ShirazUniversityShiraz71548Iran

Two structure functions W1(x,Q2) and W2(x,Q2) are determined by using the cross sections measured in the deep inelastic electron-proton scattering experiments at Stanford Linac in the energy range of 5 to 20 GeV. In this paper an alternative mathematical approach have been used in such determination, resulting in a larger n.m.er of points in the graphs of the structure functions.

关键词：结构函数无弹性散射横截面交错逼近粒子模型

Spin Cut-off Parameter of nuclear Level Density and Effective moment of Inertia

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Communications in Theoretical Physics 2005年第4期43卷 709-718页

作者： A.n.Behkami m.Soltani PhysicsDepartment ShirazUniversityShiraz71454Iran

The spin cut-off parameter of the nuclear level density and effective moment of inertia for a large n.m.er of nuclei have been determined from analysis of the experimental data on S-wave neutron resonances and spins of lowlying levels. Contrary to claims made before, it is shown the spin cut-off parameter differs considerably from their corresponding rigid body values, and the energy dependence of the effective moment of inertia confirms the interacting fermion.m.del prediction.

关键词： spin cut-off factor effective moment of inertia