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Communications in Theoretical Physics 2021年第2期73卷 11-22页

作者： Nermeen A Elkot Mahmoud A Zaky Eid h Doha Ibrahem g Ameen Department of Mathematics Faculty of ScienceCairo UniversityGiza 12613Egypt Department of Applied Mathematics National Research CentreDokkiCairo 12622Egypt Department of Mathematics Faculty of ScienceAl-Azhar UniversityCairoEgypt

While the approximate solutions of one-dimensional nonlinear Volterra-Fredholm integral equations with smooth kermels are now well understood,no systematic studies of the numerical solutions of their multi-dimensional counterparts *** this paper,we provide an efficient numerical approach for the multi-dimensional nonlinear Volterra-Fredholm integral equations based on the multi-variate Legendre-collocation *** collocation methods for multi-dimensional nonlinear integral equations are known to cause major difficulties from a convergence analysis point of ***,rigorous error estimates are provided in the weighted Sobolev space showing the exponential decay of the numerical *** existence and uniqueness of the numerical solution are *** experiments are provided to support the theoretical convergence *** results indicate that our spectral collocation method is more flexible with better accuracy than the existing ones.

关键词： spectral collocation method convergence analysis multi-dimensional integral equations

Efects of Molybdenum Concentration and Valence State on the Structural and Magnetic Properties of BaFe_(11.6)Mo_xZn_(0.4-x)O_(19) hexaferrites

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Acta Metallurgica Sinica(English Letters) 2013年第5期26卷 509-516页

作者： g.h.Dushaq S.h.Mahmood I.Bsoul h.K.Juwhari B.Lahlouh M.A.AlDamen Physics Department The University of Jordan Physics Department Al al-Bayt University Chemistry Department The University of Jordan

Barium hexaferrites BaFe11.6Mox Zn0.4-x O19（x=0.1,0.2,0.4）were prepared by precipitation of the precursors using wet chemical mixture method and then sintering the dried powders at 1100℃.The properties of the prepared samples were investigated using X-ray difraction（XRD）,scanning electron microscopy（SEM）,vibrating sample magnetometer,and Mssbauer *** patterns revealed that all prepared samples had BaFe12O19hexaferrite structure as a majority *** images demonstated that the samples consisted mainly of hexagonal platelet-like grains with diameters ranging from 100 to 500 nm.Mssbauer spectra revealed that Zn2＋ions occupy 4f1 sites leading to the splitting of the 12k *** Mo6＋ions occupy 2b sites while Mo4＋ prefer 4f1 and 12k *** the sample with x=0.4,Mo6＋and Mo4＋ ions were found to have preference for 2b and 12k sites,respectively,and to induce the development of Fe2＋ions in the hexaferrite,leading to noticeable changes in the magnetic properties of the *** observed magnetic properties were found to be consistent with the preferential site occupation of metal ions,and the hyperfine fields derived from Mssbauer spectra of these samples.

关键词： Coercivity Barium hexaferrites Mossbauer spectroscopy Magneticproperties hyperfine Interactions

Magnetic moments and g-factors in odd-A ho isotopes

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Chinese Physics C 2017年第7期41卷 52-60页

作者： E.Tabar h.Yakut A.A.Kuliev h.Quliyev g.hosgor Physics Department Sakarya University 54187 Sakarya Turkey Biomedical magnetic and semiconductor materials research center (BIMAYAM) Sakarya University 54187 Sakarya Turkey Azerbaijan National Academy of Aviation Baku Azerbaijan

The ground-state magnetic moment, g K factor and quenching spin gyromagnetic ratio have been calculated using the microscopic method based on the Quasiparticle Phonon Nuclear Model（QPNM） for ^155-169 ho nuclei for the first time. It is shown that the residual spin-spin interactions are responsible for the core polarization,and because of the core polarization the spin gyromagnetic factors are quenched. By considering the core polarization effects, a satisfactory agreement is obtained for the computed ground state g K factor, which gives an intrinsic contribution to the magnetic moments. In order to assess the collective contribution to the magnetic moments, the rotational gyromagnetic factors g R have been also calculated within the cranking approximation using the single particle wave function of the axially symmetric Woods-Saxon potential. For the ground-state magnetic moments of odd-proton ^155-165 ho nuclei, a good description of the experimental data is obtained with an accuracy of 0.01–0.1μN. From systematic trends, the quenching spin gyromagnetic factor, g K factor and magnetic moment have also been theoretically predicted for167,169 ho where there is no existing experimental data.

关键词： deformed odd-A ho isotopes magnetic moment magnetic g-factors core-polarization QRPA

Chemical effects on the sliding friction of Ag and Au(111)

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Friction 2018年第1期6卷 84-97页

作者： h.E.KO S.g.KWAN h.W.PARK A.CARON Korea Tech–Korea University of Technology and Education

We have investigated the sliding friction behavior of metallic couples with different enthalpy of mixing or reaction by friction force microscopy. Comparing the friction behavior of miscible and immiscible couples we find that in the first case friction is governed by adhesion while the shear strength is low(τ = 3–6 MPa). In the latter case of immiscible couples, adhesion is found to be low and the shear strength is large(τ≈ 70 MPa). Statistical analysis of atomic stick-slip images recorded on an Au(111) surface with tips of different affinities with gold allows for a deeper understanding of our results. The periodicity of atomic stick-slip images corresponds to the interatomic distance of gold for immiscible counter-bodies. In contrast, for a reactive couple the periodicity of atomic stick-slip significantly differs from the gold interatomic distance and may correspond to the structural length of an ordered intermediate phase at the tip-surface interface.

关键词： metals surface friction nanotribology atomic force microscopy

ChARACTERIZATION OF ThERMO-MEChANICAL FATIgUE PROPERTIES FOR PARTICULATE REINFORCED COMPOSITES

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Acta Metallurgica Sinica(English Letters) 2004年第4期17卷 534-541页

作者： h.J.Shi h.X.Mei R.guo g.Mesmacque Key Lab. of Failure Mechanics Department of Engineering Mechanics Tsinghua University Beijing 100084 ChinaKey Lab. of Failure Mechanics Department of Engineering Mechanics Tsinghua University Beijing 100084 ChinaKunming University of Science and Technology Kunming 650093 ChinaLab. of Mechanics of Lille University of Lille 1 Villeneuve d'Ascq 59500 France

A Voronoi cell dement, formulated with creep, thermal and plastic strain was applied for investigation of thermo-mechanical fatigue behavior for particulate reinforced composites. Under the in-phase fatigue loading, the maximum of tensile deformation at the maximum given loading are larger than that at the same maximum under the out-phase fatigue. The stiffness decreases nonlinearly with the increasing of the phase angle, which results in increasing of the area of fatigue loop curve and the decrease in fatigue life. The spatially centralizing of inclusions results in decreasing of the plastic strain amplitude and the area of fatigue loop curve, which will also reduce the consumption of single-circle plastic strain energy and prolong the fatigue life.

关键词： thermo-mechanical fatigue particulate reinforced composites,voronoi element phase angle

Single-molecule DNA sequencing using two-dimensionalTi2C(Oh)2 MXene nanopores: A first-principles investigation

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Nano Research 2022年第11期15卷 9843-9849页

作者： Jariyanee Prasongkit Sirichok Jungthawan Rodrigo g.Amorim Ralph h.Scheicher Division of Physics Faculty of ScienceNakhon Phanom UniversityNakhon Phanom 48000Thailand School of Physics Institute of ScienceSuranaree University of Technology111 University AveNakhon Ratchasima 30000Thailand Center of Excellence in Advanced Functional Materials Suranaree University of TechnologyNakhon Ratchasima 30000Thailand Thailand Center of Excellence in Physics Ministry of Higher EducationScienceResearch and Innovation328 Si Ayutthaya RoadBangkok 10400Thailand Departamento de Física ICExUniversidade Federal Fluminense-UFFVolta Redonda/RJ 27213-145Brazil Division of Materials Theory Department of Physics and AstronomyUppsala UniversityUppsala SE-75120Sweden

Nanopore-based devices have provided exciting opportunities to develop affordable label-free DNA sequencing *** a decade ago,graphene has been proposed as a two-dimensional(2D)nanopore membrane in order to achieve single-base ***,it was experimentally revealed that clogging of the graphene nanopore can occur due to the hydrophobic nature of graphene,thus hindering the translocation of *** overcome this problem,the exploration of alternative 2D materials has gained considerable interest over the last *** we show that a Ti_(2)C-based MXene nanopore functionalized by hydroxyl groups(–Oh)exhibits transverse conductance properties that allow for the distinction between all four naturally occurring DNA *** have used a combination of density functional theory and non-equilibrium green’s function method to sample over multiple orientations of the nucleotides in the nanopore,as generated from molecular dynamics *** conductance variation resulting from sweeping an applied gate voltage demonstrates that the Ti_(2)C-based MXene nanopore possesses high potential to rapidly and reliably sequence *** findings open the door to further theoretical and experimental explorations of MXene nanopores as a promising 2D material for nanopore-based DNA sensing.

关键词： nanopore DNA sequencing MXenes first-principles quantum transport

Malaria prevalence in north-eastern Nigeria:A cross-sectional study houben Ch^(1*),Fleischmann h^2,gǜckel M^3

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Asian Pacific Journal of Tropical Medicine 2013年第11期6卷 865-868页

作者： houben Ch Fleischmann h gckel M Diagnostic Center MMM group & Specialist hospital Yola Hospital RoadP.M.B.2266YolaAdamawa.StateNigeria Medical Mission Institute Tropical MedicineHermann Schell Str 797074 WrzburgGermany helios Kliniken Schwerin Wismarsche Str 393-39719049 SchwerinGermany

Objective:To assess the prevalence of malaria parasitemia in north-east Nigeria and to evaluate the measures for the prevention of ***:A village in north-eastern Nigeria was selected for the cross sectional study at the height of the rainy season in October 2011.A total of 550 inhabitants of a hamlet were recruited for this *** obtaining the consent individuals received a structured interview and were tested for malaria parasites in their blood *** testing positive for malaria were given a course of artemesinin-based combination therapy（ACT）.Results:A total of 497 inhabitants representing approximately 90 percent of the population participated:a quarter of the study group carried malaria parasitesexclusively Plasmodium falciparum（***）-representing a *** parasite rate（PfPR） of 24.5%.Besides,53/138 in the age group of 2 to hildren tested positive for *** representing a PfPR2-10 value of 38.4%.Malaria control measures were used in just under a third（157/497） of this *** these measures 28/157（17.8%） still tested positive for ***:The malaria burden is overestimated for this region in north-east *** findings support an intermediate pattern of malaria *** 30%bed nets coverage for malaria control is well below the WhO estimates for 2011.

关键词： Malaria control Malaria endemicity Malaria prevalence Malaria transmission

Editor profile:guest editor of special issue “Bile Acids and Nuclear Receptors in Digestive System and Therapy”

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Acta Pharmaceutica Sinica B 2015年第2期5卷 91-92页

作者： guo g.L. Zhou h. Department of Pharmacology and Toxicology School of Pharmacy at the Rutgers University New Jersey United States Department of Microbiology and Immunology Virginia Commonwealth University Richmond VA United States

Associate *** Liejun guo is a tenured faculty in the Department of Pharmacology and Toxicology in the School of Pharmacy at the Rutgers University in New Jersey,*** graduated from the West China University of Medical ... 详细信息

关键词： Ph Bile Acids and Nuclear Receptors in Digestive System and Therapy Editor profile

Mineralogy,M-type tetrad effect and radioactivity of altered granites at the *** garadi shear zone,central Eastern Desert,Egypt

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Chinese Journal Of geochemistry 2011年第2期30卷 153-164页

作者： El Nahas h.A. El Feky M.g. Mira h. Nuclear Materials Authority P.O. Box 530 Cairo Egypt

The g. Abu garadi area is covered mainly by metasediments, alkali feldspar granites and stream sediments. The alkali feldspar granite is traversed by a major strike-slip fault trending in an N-S direction as well as two subordinate sets of faults trending NW to WNW for the first one and NE for the second one. These faults represent the shear zones affected by magmatic (syngenetic) as well as hydrothermal (epigenetic) activities causing alteration of the granitic rocks. The most common alteration features are albitization, greisenization and koalinitization. The mass balance calculations of the studied altered samples show enrichments in Zr, Y, Ni, U, Th and ga and depletions in Zn, Sr, Nb, Ba, Pb, Cu and V. Only the greisenized samples exhibit a significant enrichment in Nb, ∑REE budget and pronounced lanthanide tetrad effect (M-type), especially TE1,4, while weakly expressed tetrad effects are for the other albitized and koalinitized samples. Mineralogically, the common accessory minerals in the altered samples include samarskite-(Y), betafite, uranothorite, zircon, fluorite and cassiterite. The greisenized granites contain high eU and eTh than the other altered types, where they are characterized by an assemblage of the radioactive minerals; samarskite-(Y), betafite, uranothorite in addition to zircon. The inter-element relationships between U and Th and also their ratios illustrate that the radioelement distribution in these granites is mainly governed by magmatic processes, in addition to post-magmatic ones. The distribution of chemical elements and the fractionation of some isovalents within the shear zone are largely controlled by the newly formed mineral phases. With respect to uranium mobilization, uranium migrated from the host alkali feldspar granites of g. Abu garadi, while the shear zones acted as traps for the migrated uranium. Moreover, U migrated in the shear zone during greisenization and albitization, and migrated out during koalinitization.

关键词： M 类型四个效果改变的花岗石 g。Abu garadi 砍地区中央东方沙漠埃及

Analysis on the high‑quality development of nuclear energy under the goal of peaking carbon emissions and achieving carbon neutrality

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Carbon Neutrality 2022年第1期1卷 141-152页

作者： Ronghua Chen g.h.Su Kui Zhang School of Nuclear Science and Technology Xi’an Jiaotong UniversityXi’an 710049China

Striving to peak carbon emissions and achieve carbon neutrality(known as the"Dual-Carbon"goal)is an inevitable requirement for elevating the environmental resource constraints and realizing harmonious coexistence between the mankind and the *** the energy system,nuclear energy offers various advantages,such as high energy density,low carbon emission,strong environmental adaptability and large potential for energy co-generation and *** is one of the supporting energy sources for the transformation and upgradation of the energy system to a clean,efficient and low-carbon *** this paper,the opportunities and challenges for innovation-driven nuclear energy development in the fields of electricity generation,hydrogen production,heat supply and seawater desalination under the goal of"Dual-Carbon"are discussed and ***,the relevant research on improving the safety and economy of the pressurized water reactor(PWR)and sodium-cooled fast reactor(SFR)conducted by the Nuclear Thermal-hydraulic research Lab(NuTheL)of Xi’an Jiaotong University is briefly introduced.

关键词： "Dual-Carbon"goal Nuclear energy NuTheL PWR SFR