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Reduced transition probabilities for 4He radiative capturereactions at astrophysical energies

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Research in Astronomy and Astrophysics 2014年第3期14卷 367-372页

作者： Hossein Sadeghi Reza ghasemi Department of Physics Faculty of ScienceArak University

The reduced transition probabilities from an electric quadrupole B（E2） andreduced transition probabilities from a magnetic dipole B（M1） between the groundstate and the first excited state have been calculated for the 3He（α,γ）7Be, 8Be（α,γ）12cand 12C（α,γ）160 radiative capture reactions with the M3Y potential. These reactionsare important in stellar evolution. The calculated B（M1） and B（E2） for 7Be nuclei arefound to be 1.082 x 10-3 e2 fm2 and 1.921 e2 fma from transitions 3/2- to 1/2-, re-spectively. The obtained values for reduced transition probabilities B（E2） for the 12Cand 160 nuclei from transitions 0＋ to 2＋ are 12.54 e2 fm4 and 14.18 e2 fm4, respec-tively. The results are in satisfactory agreement with available experimental data.

关键词： nuclear reactions abundances methods: numerical

Performance improvement of a crumb rubber modified bitumen using recycled glass powder

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第11期14卷 805-814页

作者： Mojtaba ghasemi Seyed Morteza MARANDI Department of Civil Engineering Shahid Bahonar UniversityKerman 761691 4111 Iran

In this study, the efficiency of bitumen and asphalt mixtures modified with crumb rubber(CR) and recycled glass powder(RGP) is evaluated. From an environmental point of view, the application of RGP in asphalt mixtures is considered beneficial since it prevents accumulation of waste glass in the natural environment. Rheological and mechanical properties of modified bitumen samples were investigated by laboratory methods such as bitumen conventional tests and dynamic shear rheometer(DSR), and also by asphalt mixture performance tests including Marshall stability, indirect tensile strength(ITS),compressive strength, and indirect tensile stiffness modulus. The results showed that the application of RGP in place of CR has no negative impact on the efficiency of bitumen and asphalt mixtures and even improves their engineering properties except for the toughness index(TI). Moreover, a modification with 5% CR and 5% RGP in asphalt mixtures results in the best overall performance.

关键词： Crumb rubber (CR) Recycled glass powder (PGP) Rheological properties Performance testing Stone matrixasohalt (SMA)

Enhancing water splitting via weakening H_(2) and O_(2) adsorption on NiCo-LDH@CdS due to interstitial nitrogen doping: A close look at the mechanism of electron transfer

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Journal of Energy Chemistry 2021年第6期30卷 118-130,I0004页

作者： Azam Pirkarami Sousan Rasouli Ebrahim ghasemi Department of Nanomaterials&Nanocoatings Institute for Color Science and Technology(ICST)TehranIran Inorganic Pigment and Glazes Department Institute for Color Science and TechnologyTehranIran Center of Excellence for Color Science and Technologies Institute for Color Science and TechnologyTehranIran

This paper is a report on the development of a convenient approach to fabricating a very efficient hybrid photoelectrocatalyst for water *** photoelectrocatalyst consists of nickel-cobalt layered double hydroxide as the core,cadmium sulfide as the shell,and nitrogen,hence NiCo-LDH@*** the electrocatalytic activity to be improved,the H_(2) and O_(2) binding energy needs to be *** interstitial nitrogen doping on NiCo-LDH@CdS can increase electrocatalytic activity to a great ***@CdS nanoparticles are obtained by subjecting to nitriding the NiCo-LDH@CdS electrode coated with polyvinylpyrrolidone *** electrode has a large specific surface area,allows fast transfer of electrons,and exhibits long-term *** experimental results presented in this paper reveal that interstitial nitrogen doping largely reduces H_(2) and O_(2) binding energy and lowers the activation barrier for the formation and splitting of water.

关键词： Water splitting Interstitial nitrogen doping Nitriding Two-redox/semiconductor liquid junction Hydrogen evolution reaction Oxygen evolution reaction

Faunal data and envenomation emergency first aid of cone snails (Conus spp.) in Qeshm Island, the Persian Gulf

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Asian Pacific Journal of Tropical Medicine 2017年第12期10卷 1167-1171页

作者： Mehdi Khoobdel Hadi Dehghani Ali Mehrabi Tavana Mohammad ghasemi Seyyed Mohammad Dakhteh Majid Askari Hesni mohsen Rezaie-Atagholipour Health Research Center Baqiyatallah University of Medical SciencesTehranIran Department of Marine Biology Faculty of ScienceUniversity of HormozganBandar AbbasIran Health Management Research Center Baqiyatallah University of Medical SciencesTehranIran Environmental Management Office Qeshm Free Area OrganizationQeshm IslandIran Department of Biology Faculty of ScienceShahid Bahonar University of KermanKermanIran

Objective: To investigate the fauna of a highly venomous marine species group, the cone snails(Family Conidae), in the shores of Qeshm Island, of evaluating the possibility of envenomation in the area and summarize recommendations for emergency first ***: Shores surrounding Qeshm Island were surveyed to collect cone snails during cold(February and March) and warm(May and June) seasons of 2017. Collected snails were identified to the species level. Abundance and species richness were estimated in shores of different structures, including muddy and sandy-rocky shores. Also, the most updated medical literature was reviewed to summarize related emergency first ***: Three cone snail species were recorded from southern sandy-rocky shores of the Island, in decreasing order of abundance, included crowned cone(Conus coronatus)(65%), feathered cone(Conus pennaceus)(28%), and frigid cone(Conus frigidus)(7%).Abundance of these species were significantly higher in cold season compared to the warm season(P < 0.05). No cone snails were recorded along the northern muddy shores of the ***: Envenomation can cause various symptoms ranging from minor local pain to systemic paralysis and death due to respiratory failure. We recommend an awareness programme for the seashore visiting public.

关键词： Envenomation symptoms Subtropical coastal waters Sandy shores Venom

Microstructures, hardening and tribological behaviors of tin matrix composites reinforced with SiC and Zn particles

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Rare Metals 2021年第9期40卷 2584-2592页

作者： Fatemeh ghasemi Mohammad Moazami-Goudarzi Hamidreza Najaﬁ Department of Materials Engineering Science and Research BranchIslamic Azad UniversityTehran ***Iran

In order to strengthen pure tin and improve its dry sliding resistance, Sn/SiC and Sn/Zn composites were fabricated via a powder metallurgy route. Microstructure,hardness and pin-on-disk wear resistance of pure tin and the fabricated composites were compared to those of Sn–7.5 Sb–3.5 Cu Babbitt alloy. The dominant wear mechanism at different applied loads was determined by analyzing worn surfaces and wear debris in each case. The results showed that the hardening effect of Zn was much higher than that of SiC. The hardening role of Zn in the tin matrix was ascribed to the direct load transfer mechanism. Microscopic studies of the worn surfaces revealed that the pure tin was susceptible to surface fatigue wear and plowing damage, depending on the normal load applied during the wear test. In the case of Sn/SiC composite and the Babbitt alloy, delamination wear mechanism resulting from subsurface crack propagation controlled the wear rate. While the highest hardness and the lowest coefficient of friction were obtained for the Babbitt alloy, the Sn/Zn composite exhibited the highest wear resistance at a constant applied load, indicating the importance of asperity contact type in the wear process.

关键词： Tin matrix composites Babbitt alloy Microstructure Hardening mechanisms Wear behavior

Determination of captopril in pharmaceutical preparation and biological fluids using two- and three-way chemometrics methods

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Chinese Chemical Letters 2007年第4期18卷 427-430页

作者： Nahid ghasemi Ali Niazi Department of Chemistry Faculty of SciencesAzad University of ArakArakIran

Spectrophotometric method has been developed for the direct quantitative determination of captopril in pharmaceutical preparation and biological fluids （human plasma and urine） samples. The method was accomplished based on parallel factor analysis （PARAFAC） and partial least squares （PLS）. The study was carried out in the pH range from 2.0 to 12.8 and with a concentration from 0.70 to 61.50μg mL^-1 of captopril. Multivariate calibration models such as PLS at various pH and PARAFAC were elaborated from ultraviolet spectra deconvolution and captopril determination. The best models for this system were obtained with PARAFAC and PLS at pH 2.0. The applications of the method for determination of real samples were evaluated by analysis of captopril in pharmaceutical preparations and biological fluids with satisfactory results. The accuracy of the method, evaluated through the RMSEE was 0.5801 for captopril with best calibration curve by PARAFAC and 0.6168 for captopril with PLS at pH 2.0 model.

关键词： Captopril Spectrophotometric Parallel factor analysis Partial least squares Pharmaceutical analysis

Performance of a novel bent-up bars system not interacting with concrete

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Frontiers of Structural and Civil Engineering 2019年第6期13卷 1301-1315页

作者： Aydin SHISHEGARAN Mohammad Reza ghasemi Hesam VARAEE School of Civil Engineering Iran University of Science and TechnologyTehran 13114-16846Iran Structural Engineering Department of Civil EngineeringUniversity of Sistan and BaluchestanZahedan 98167-45845Iran Structural Engineering Ale Taha Institute of Higher EducationTehran 14888-36164Iran

Increasing the bending and shear capacities of reinforced concrete members is an interesting issue in structural *** recent years,many studies have been carried out to improve capacities of reinforced concrete members such as using post and pre-tensioning,Fiber Reinforced Polymer and other *** paper proposes a novel and significant technique to increase the flexural capacity of simply supported reinforced concrete *** proposed method uses a new reinforcement bar system having bent-up bars,covered with rubber *** technique will avoid interaction of bent-up bars with *** are located in the zone where compressive and tensile forces act against one anothe匚The compressive force in the upper point of the bent-up bars is exerted to the end point of these bars located under neutral ***,the tensile stress is decreased in reinforcements located under the neutral *** will cause the Reinforced Concrete(RC)beam to endure extra loading before reaching yield *** factors may well be considered as reasons to increase bending capacity in the new *** laboratory work together with finite element method analysis were carried out in this ***,bending capacity,ductility,strength,and cracking zone were assessed for the new proposed system and compared with the conventional *** the FEM simulation and the experimental test results revealed that the proposed system has significant impact in increasing the load bearing capacity and the stiffness of the RC *** the present study,an equation is formulated to calculate bending capacity of a new reinforcement bar system beam.

关键词： bending capacity rubber tube stress transfer bent-up bars ductility cracking

Numerical methods for solving singular integral equations obtained by fracture mechanical analysis of cracked wedge

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Applied Mathematics and Mechanics(English Edition) 2014年第3期35卷 311-324页

作者： M.GHADIRI H.ghasemi Faculty of Engineering and Technology Department of Mechanical EngineeringImam Khomeini International University

The numerical solutions to the singular integral equations obtained by the fracture mechanical analyses of a cracked wedge under three different conditions are considered. The three considered conditions are:(i) a radial crack on a wedge with a nonfinite radius under the traction-traction boundary condition,(ii) a radial crack on a wedge with a finite radius under the traction-traction boundary condition, and(iii) a radial crack on a finite radius wedge under the traction-displacement boundary condition. According to the boundary conditions, the extracted singular integral equations have different forms. Numerical methods are used to solve the obtained coupled singular integral equations, where the Gauss-Legendre and the Gauss-Chebyshev polynomials are used to approximate the responses of the singular integral equations. The results are presented in figures and compared with those obtained by the analytical response. The results show that the obtained Gauss-Chebyshev polynomial response is closer to the analytical response.

关键词： fracture mechanics numerical analytical singular integral equation Gauss-Legendre

Effect of natural and synthetic fibers reinforcement on California bearing ratio and tensile strength of clay

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第3期13卷 626-642页

作者： Mahdi ghasemi Nezhad Alireza Tabarsa Nima Latifi Department of Civil Engineering Faculty of EngineeringGolestan UniversityGorganIran Terracon Consultants Inc.5217 Linbar Dr#309NashvilleTN37211USA

Use of environmentally friendly approaches with the purpose of strengthening soil layers along with finding correlations between the mechanical characteristics of fiber-reinforced soils such as indirect tensile strength(ITS)and California bearing ratio(CBR)and as well as the evaluation of shear strength parameters obtained from the triaxial test would be very effective at geotechnical construction *** research was aimed at investigating the influence of natural fibers as sustainable ones including basalt(BS)and bagasse(BG)as well as synthetic polyester(PET)fibers on the strength behavior of clayey *** this end,the effects of various fiber contents(0.5%,1%and 2%)and lengths(2.5 mm,5 mm and 7.5 mm)were experimentally *** conducting ITS and CBR tests,it was found that increasing fiber content and length had a significant influence on CBR and ITS ***,2%of 7.5 mm-long fibers led to the largest values of CBR and *** CBR values of soil reinforced with PET,BS,and BG fibers were determined as 19.17%,15.43%and 13.16%,*** ITS values of specimens reinforced with PET,BS,and BG fibers were reported as 48.57 kPa,60.7 kPa and 47.48 kPa,*** results of the triaxial compression test revealed that with the addition of BS fibers,the internal friction angle increased by about 100%,and with the addition of PET fibers,the cohesion increased by about 70%.Moreover,scanning electron microscope(SEM)analysis was employed to confirm the *** relationship between CBR and ITS values,obtained via statistical analysis and used for the optimum design of road pavement layers,demonstrated that these parameters had high correlation *** outcomes of multiple linear regression and sensitivity analysis also confirmed that the fiber content had a greater effect on CBR and ITS values than fiber length.

关键词： Natural fibers Synthetic fibers Indirect tensile strength(ITS) California bearing ratio(CBR) Reinforced soil