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Photon Linear Polarization Coefficient of the Radiative Capture Process ^(2)h(p,γ)^(3)he at Thermal Energies

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Chinese Physics Letters 2012年第12期29卷 52-56页

作者： h.Sadeghi Department of Physics Faculty of ScienceArak UniversityArak 8349-8-38156Iran

The photon polarization parameter of the proton-deuteron radiative capture process at thermal proton energies is calculated up to leading order(LO),using pionless effective field theory(EFT).In order to make a comparative study of this model,we compare our results for the photon polarization parameter with the realistic Argonne(AV14)and Argonne v18(AV18)modern nucleon-nucleon potentials and Urbana IX or Tucson-Melbourne three-nucleon *** theoretical description of the ^(2)h(p,γ)^(3)he reaction at thermal energies is complicated by the presence of the Coulomb *** the s-wave capture contribution to the thermal energy of this reaction is ***-body currents give small but significant contributions to some of the observables in the proton-deuteron radiative capture cross section at thermal neutron *** result is in good agreement with the available experimental data and potential models'calculation at this order.

关键词： interaction. radiative Polarization

S-Factor of the ^(3)h(α,γ)^(7)Li Reaction at Astrophysical Energies

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Chinese Physics Letters 2013年第10期30卷 59-62页

作者： h.Sadeghi Department of Physics Faculty of ScienceArak UniversityArak 8349-8-38156Iran

The astrophysical S-factor forα-^(3)h radiative capture is calculated at astrophysical *** construct conserved two-and three-body electromagnetic currents,using minimal substitution in the explicit momentum dependence of the two-and three-nucleon *** realistic Argonne v_(18) two-nucleon and Urbana IX or Tucson–Melbourne three-nucleon interactions are considered for *** extrapolation of results for the astrophysical S-factor at zero energy,the energy in the order of 1 keV and less is found to be S(0)=0.107(0.112)keV·b,with(without)three-body interactions in satisfactory agreement with other theoretical results and experimental data.

关键词： calculation substitution momentum

Molecular Application of a State Specific Multi-Reference Brillouin-Wigner Perturbation Theory

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Chinese Physics Letters 2016年第2期33卷 22-25页

作者： h.Aksu Department of Physics Bilecik University

The single reference second order Brillouin-Wigner perturbation theory recently developed, which eliminates its size-extensivity error, has been generalized to state-specific, multi-reference （SS-MR）, BWPT2 providing a size-extensive correction to the electron correlation problem for systems that demand the use of a multi-reference function. Illustrative numerical tests of the size-extensivity corrections are made for widely used molecules in their ground states, which are pronounced multi-reference characteristics. We have implemented two-reference and three-reference cases for Ch2, Bh and bond breaking process in the ground states of hF molecules. The results are compared with the rigorously size-extensive methods such as the M^ller-Plesset perturbation theory, i.e., MP2, full configuration interaction （Full-CI） and allied methods using the same basis sets.

关键词： of in Molecular Application of a State Specific Multi-Reference Brillouin-Wigner Perturbation Theory FCI CCSD CISD RhF MRCI CASSCF for been MP is

Q-Switched Ytterbium-Doped Fiber Laser Using Black Phosphorus as Saturable Absorber

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Chinese Physics Letters 2016年第5期33卷 54-57页

作者： A.h.h.Al-Masoodi M.h.M.Ahmed A.A.Latiff h.Arof S.W.harun Department of Electrical Engineering Faculty of EngineeringUniversity of Malaya Photonics Research Center University of Malaya

We demonstrate a Q-switched ytterbium-doped fiber laser （YDFL） using a newly developed multi-layer black phosphorous （BP） saturable absorber （SA）. The BP SA is prepared by mechanically exfoliating a BP crystal and sticking the acquired BP flakes onto a scotch tape. A small piece of the tape is then placed between two ferrules and incorporated in a YDFL cavity to achieve a stable Q-switched operation in a 1.0 μm region. The laser has a pump threshold of 55.1 mW, a pulse repetition rate that is tunable from 8.2 to 32.9 khz, and the narrowest pulse width of 10.8 μs. The highest pulse energy of 328 nJ is achieved at the pump power of 97.6 mW. Our results show that multi-layer BP is a promising SA for Q-switching laser operation.

关键词： of SA Q-Switched Ytterbium-Doped Fiber Laser Using Black Phosphorus as Saturable Absorber in is for BP that Figure khz mode

Novel synthesis of stabilized Bi_(1-x-y)Gd_(x)Dy_(y)O_(1.5) solid electrolytes with enhanced conductivity for intermediate temperature solid oxide fuel cells(SOFCs)

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Journal of Rare Earths 2024年第10期42卷 1903-1911页

作者： Ahmed h.Ibrahim Yehia M.Abbas h.A.Ayoub Marwa h.Ali Mustafa Aldoori Materials Science Laboratory Physics DepartmentFaculty of ScienceSuez Canal University41522IsmailiaEgypt Ministry of higher Education and Scientific Research Aliraqia University10011BaghdadIraq

herein,we report the synthesis of a Dy-Gd co-doped cubic phase-stabilized Bi_(2)O_(3) solid electrolyte system via solid-state processing under atmospheric *** with Dy^(3+) and Gd^(3+) has been observed to significantly enhance the densification process during sintering for stabilization purposes,thereby improving the electrical properties of δ-Bi_(2)O_(3)-type *** synthesized ceramics were characterized using X-ray diffraction(XRD),field emission scanning electron microscopy-energy dispersive X-ray spectroscopy(FESEM-EDX),thermal gravimetry/differential thermal analysis(TG/DTA),and the four-point probe technique(4PPT).XRD analysis reveals that the samples Bi_(1-x-y)Gd_(x)Dy_(y)O_(1.5)(y=0.05/x=0.05,0.10,0,15,and 0.20,and x=0.05/y=0.10,0.15,and 0.20) exhibit a stable face-centered cubic δ-phase and a mixed-phase crystallographic *** XRD analysis of the stabilized δ-phase suggests that the prepared oxides show a face-centered cubic(FCC) structure with a space group of *** micrographs reveal that the composition Bi_(0.90)Gd_(0.05)Dy_(0.05)O_(1.5) has no significant ***,an evident increase in the pore formation is observed as the amount of Gd_(2)O_(3) increases until it reaches 20%.This finding suggests that dense pellets are formed during the sintering process at 900-1000℃.The DTA analyses were performed to verify the phase stability,which agrees with the XRD *** electrochemical performance of the synthesized Dy-Gd co-doped Bi_(2)O_(3)solid electrolyte system was evaluated and analyzed in detail by using the electrochemical impedance spectroscopy(EIS) technique,Based on EIS and conductivity measurements,Bi_(0.75)Gd_(0.20)Dy_(0.05)O_(1.5) exhibits the lowest activation energy of 0.519 eV and the highest conductivity value of 0.398 S/cm at 627℃compared to the other samples;this composition can be used as a solid electrolyte for intermediatetemperature solid oxide fuel cells(SOFCs).

关键词： Solid oxide fuel cells(SOFCs) Rare earths Solid-state processing Rietveld Fast Fourier transform(FFT) Electrochemical impedance spectroscopy(EIS)

Analytical model for thermal lensing and spherical aberration in diode side-pumped Nd:YAG laser rod having Gaussian pump profile

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Chinese Physics B 2015年第12期24卷 334-341页

作者： M h Moghtader Dindarlu M Kavosh Tehrani h Saghafifar A Maleki Institute of Optics and Laser Malek-Ashtar University of Technology

In this paper, according to the temperature and strain distribution obtained by considering the Gaussian pump profile and dependence of physical properties on temperature, we derive an analytical model for refractive index variations of the diode side-pumped Nd：YAG laser rod. Then we evaluate this model by numerical solution and our maximum relative errors are 5% and 10% for variations caused by thermo–optical and thermo–mechanical effects; respectively. Finally, we present an analytical model for calculating the focal length of the thermal lens and spherical aberration. This model is evaluated by experimental results.

关键词： side-pumped laser rod Gaussian pump profile thermal effects thermal lens spherical aberration

MODIFICATION OF SODIUM SALT OF PARTIALLY CARBOXYMEThYLATED TAMARIND KERNEL POWDER ThROUGh GRAFTING WITh ACRYLONITRILE: SYNThESIS, ChARACTERIZATION AND SWELLING BEhAVIOR

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Chinese Journal of Polymer Science 2013年第12期31卷 1670-1684页

作者： J.h.Trivedi J.R.Jivani K.h.Patel h.C.Trivedi P.G.Dept.of Chemistry Sardar Patel UniversityVallabh Vidyanagar Amneal Phamaceuticals

A graft copolymer of polyacrylonitrile （PAN） with sodium salt of partially carboxymethylated tamarind kernel powder （Na-PCMTKP, DS ^-= 0.15） was synthesized by using ceric ammonium nitrate （CAN） as a redox initiator in an aqueous medium. The optimum reaction conditions for affording maximum percentage of grafting were established by successively varying reaction conditions such as concentrations of nitric acid, CAN, monomer （AN） as well as reaction time, temperature and amount of substrate. The influence of these reaction conditions on the grafting yields was discussed. The kinetic scheme of free radical graft copolymerization was proposed and the experimental results were found to agree very well with the proposed kinetic scheme. The graft copolymer （Na-PCMTKP-g-PAN, percentage of grafting G = 413.76% and percentage of grafting efficiency GE = 96.48%） sample synthesized under the established optimized reaction conditions was hydrolyzed by 0.7 mol-L l NaOh solution at 90-95 ℃ to yield the superabsorbent hydrogel, h-Na-PCMTKP-g-PAN. The swelling behavior of the hydrogel was studied by carrying out its absorbency measurements in low conductivity water, 0.15 mol·L^-1 salt （NaCl, CaCl2 and AlCl3） solutions and simulated urine （SU） solution at different timings. FTIR, TGA and SEM techniques were used to characterize the products.

关键词： Sodium salt of partially carboxymethylated tamarind kernel powder Acrylonitrile Graft copolymerization Superabsorbent hydrogels Swelling behavior.

Microstructure evolution of a recycled Al-Fe-Si-Cu alloy processed by tube channel pressing

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International Journal of Minerals,Metallurgy and Materials 2018年第10期25卷 1166-1172页

作者： M.h.Farshidi M.Rifai h.Miyamoto Department of Materials Science and Metallurgical Engineering Ferdowsi University of Mashhad Department of Mechanical Engineering Doshisha University

Although excellent recyclability is one of the advantages of Al alloys, a recycling process can reduce different properties of these alloys by adding coarse AlFeSi particles into the alloys' microstructures. One of the well-known methods for modifying the microstructure of metallic materials is the imposition of severe plastic deformation(SPD). Nevertheless, the microstructure evolutions of recycled Al alloys containing extraordinary fractions of AlFeSi particles during SPD processing have seldom been considered. The aim of the present work is to study the microstructure evolution of a recycled Al–Fe–Si–Cu alloy during SPD processing. For this purpose, tubular specimens of the mentioned alloy were subjected to different numbers of passes of a recently developed SPD process called tube channel pressing(TCP); their microstructures were then studied using different techniques. The results show that coarse AlFeSi particles are fragmented into finer particles after processing by TCP. however, decomposition and dissolution of AlFeSi particles through TCP processing are negligible. In addition, TCP processing results in an increase in hardness of the alloy, which is attributed to the refinement of grains, to an increase of the dislocation density, and to the fragmentation of AlFeSi particles.

关键词： AlFeSi intermetallic particle severe plastic deformation microstructure tube channel pressing

A New Treatment for Some Periodic Schr?dinger Operators Ⅱ: The Wave Function

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Communications in Theoretical Physics 2018年第6期69卷 645-654页

作者： Wei h School of Electronic Engineering Chengdu Technological UniversityChengdu 611730China

Following the approach of our previous paper we continue to study the asymptotic solution of periodic Schrodinger operators. Using the eigenvalues obtained earlier the corresponding asymptotic wave functions are derived. This gives further evidence in favor of the monodromy relations for the Floquet exponent proposed in the previous paper. In particular, the large energy asymptotic wave functions are related to the instanton partition function of N = 2 supersymmetric gauge theory with surface operator. A relevant number theoretic dessert is appended.

关键词： spectral theory periodic differential operators Seiberg-Witten duality instanton partition function