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Comparison of Antioxidant Status between Pilots and Non-flight Staff of the Army Force: Pilots May Need More Vitamin C

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Biomedical and Environmental Sciences 2014年第5期27卷 371-377页

作者： Elham Amiri Taleghani Gity Sotoudeh kazem amini Mahboubeh Heidari Araghi Babak Mohammadi Haleh Sadrzadeh Yeganeh Department of Community Nutrition School of Nutritional Sciences and Dietetics Tehran University of Medical Sciences Department of Aerospace Medicine School of Aerospace Medicine Army University of Medical Sciences Department of Nutrition School of Health Yazd University of Medical Sciences

Objective To compare the blood antioxidant levels and dietary antioxidant intakes between pilots and non-flight staff of the Army Force in The Islamic Republic of Iran. Methods Thirty-seven helicopter pilots and 40 non-flight staff were included in this study. Their general characteristics were recorded and their weight, height, and waist circumference were measured. Their daily intake of energy and nutrients including antioxidants was assessed using a semi-quantitative food frequency questionnaire. Serum levels of total antioxidant capacity （TAC）, malondialdehyde （MDA）, and glutathione reductase （GR）, glutathione peroxidase （GPx）, superoxide dismutase （SOD）, and catalase （CAT） in red blood cells were also measured. Results The median erythrocytes SOD, serum MDA level and the mean serum level of TAC and erythrocytes GPx were significantly higher in pilots than in non-flight staff. The median vitamin C intake was significantly lower in pilots than in non-flight staff. The serum MDA levels were similar in non-flight staff and pilots when their vitamin C intake was 〈168 mg and significantly lower in non-flight staff than in pilots when their vitamin C intake was 〉168 mg. Conclusion The serum MDA level is lower in non-flight staff than in pilots when their vitamin C intake level is high, indicating that pilots need more vitamin C than non-flight staff.

关键词： Antioxidant status Pilots Army force

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Numerical study of flow and thermal characteristics of pulsed impinging jet on a dimpled surface

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Theoretical & Applied Mechanics Letters 2024年第2期14卷 106-117页

作者： Amin Bagheri kazem Esmailpour Morteza Heydari Renewable Energy Research Center Damavand BranchIslamic Azad UniversityDamavandIran

This research comprehensively investigates the flow and thermal characteristics of a pulsating impinging jet over a dimpled *** analyzes the impact of key parameters(e.g.,inlet velocity pulsation functions,pulsation frequency,amplitude,dimple pitch,dimple depth,Reynolds number)on flow patterns and heat *** computational fluid dynamics and the Re-normalization group turbulence model are employed to accurately simulate complex turbulent flow *** and average heat transfer coefficients are calculated and compared to steady impingement cases,revealing the potential benefits of pulsation for heat transfer *** study also examines how pulsation-induced flow modulation and thermal mixing affect heat transfer *** indicate that combining fluctuating flow with a dimpled surface can improve heat transfer *** summary,increasing pulsation amplitude consistently enhances heat transfer,while the effect of frequency varies between impinging and wall jet zones.

关键词： Pulsating impinging jet Dimpled surface Heat transfer enhancement Pulsation frequency and amplitude Coherent structures

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Transient Stability Analysis of Grid-connected Converters in Wind Turbine Systems Based on Linear Lyapunov Function and Reverse-time Trajectory

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 782-790页

作者： Mohammad kazem Bakhshizadeh Sujay Ghosh Guangya Yang Łukasz Kocewiak Ørsted Wind Power A/S Nesa Allé12820Denmark Technical University of Denmark Anker Engelunds Vej 12800Denmark

As the proportion of converter-interfaced renewable energy resources in the power system is increasing,the strength of the power grid at the connection point of wind turbine generators(WTGs)is gradually *** research has shown that when connected with the weak grid,the stability of the traditional grid-following controlled converters will deteriorate,and they are prone to unstable phenomena such as *** to the limitations of linear analysis that cannot sufficiently capture the stability phenomena,transient stability must be *** far,standalone time-domain simulations or analytical Lyapunov stability criteria have been used to investigate transient ***,the time-domain simulations have proven to be computationally too heavy,while analytical methods are difficult to formulate for larger systems,require many modelling assumptions,and are often conservative in estimating the stability *** paper proposes and demonstrates an innovative approach to estimating the transient stability boundary via combining the linear Lyapunov function and the reverse-time trajectory *** proposed methodology eliminates the need of time-consuming simulations and the conservative nature of Lyapunov *** study brings out the clear distinction between the stability boundaries with different post-fault active current ramp rate *** the same time,it provides a new perspective on critical clearing time for wind turbine *** stability boundary is verified using time-domain simulation studies.

关键词： Lyapunov direct method non-autonomous system phase-locked loop(PLL) time trajectory reversal transient stability assessment wind turbine converter system

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Mineral Chemistry,Trace Elements,Isotopic Analysis and Zircon U-Pb Dating in the Hesar Pluton,Northern UDMA,Iran:Implications for Pre-Collisional Magma Mixing

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 657-678页

作者： kazem kazemI Soroush MODABBERI Parisa GHARIBNEJAD XIAO Yilin Fatemeh SARJOUGHIAN Ali KANANIAN School of Geology College of ScienceUniversity of TehranTehranIran Research Centre for Mineral Resources Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China National Key Laboratory of Ecological Security and Resource Utilization in Arid Areas Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Department of Geochemistry and Environmental Sciences School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China Department of Earth and Sciences Faculty of SciencesUniversity of KurdistanSanandajIran Department of Science Education Farhangian UniversityTehranIran

The Hesar pluton in the northern Urumieh-Dokhtar magmatic arc hosts numerous mafic-microgranular enclaves(MMEs).Whole rock geochemistry,mineral chemistry,zircon U-Pb and Sr-Nd isotopes were *** is suggested that the rocks are metaluminous(A/CNK=1.32-1.45),subduction-related I-type calc-alkaline gabbro to diorite with similar mineral assemblages and geochemical *** host rocks yielded an U-Pb crystallization age of 37.3±0.4 Ma for *** have relatively low SiO_(2) contents(52.9-56.6 wt%)and high Mg^(#)(49.8-58.7),probably reflecting a mantle-derived ***-and mantle-normalized trace element patterns are characterized by LREE and LILE enrichment,HREE and HFSE depletion with slight negative Eu anomalies(Eu/Eu^(*)=0.86-1.03).The host rocks yield(^(87)Sr/^(86)Sr)_(i) ratios of 0.70492-0.70510,positive ε_(Nd)(t)values of+1.55-+2.06 and T_(DM2)of 707-736 Ma,which is consistent with the associated mafic microgranular enclaves((^(87)Sr/^(86)Sr)_(i)=0.705014,ε_(Nd)(t)=+1.75,T_(DM2)=729 Ma).All data suggest magma-mixing for enclave and host rock formation,showing a complete equilibration between mixed-mafic and felsic magmas,followed by rapid *** T_(DM1)(Nd)and T_(DM2)(Nd)model ages and U-Pb dating indicate that the host pluton was produced by partial melting of the lower continental crust and subsequent mixing with injected lithospheric mantlederived magmas in a pre-collisional setting of Arabian-Eurasian *** composition indicates a crystallization temperature of~1000℃ and a depth of~9 km.

关键词： enclave magma mixing zircon U-Pb dating Urumieh-Dokhtar magmatic arc

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Seropositivity and Other Determinants Associated with Toxoplasmosis in Local Buffalo in Iraq

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Open Journal of Veterinary Medicine 2024年第1期14卷 1-9页

作者： Rafid Jawad kazem Imad kazem Ali Department of Animal Production College of Agriculture Sumer University Al-Rifai Iraq

A cross-sectional study was conducted to determine the Seropositivity of Toxoplasma gondii in water buffalo in three Iraqi governorates (Baghdad, Dhi Qar, and Maysan) and to estimate the risk aspects related to infestation throughout the period from January to December 2019. A total of 430 serum samples were inspected with a commercial ELISA (Enzyme linked immunosorbent assay) kit. Indirect multi-species kit. The overall Seropositivity of T. gondii in the examined local buffalo was 7.4%, and the highest rate (9.3%) was in Baghdad Governorate. A multivariate regression analysis revealed that adult buffalo (OR = 7.10;95% CI: 0.87-57.68;P = 0.067) and young herds (OR = 8.42;95% CI: 1.07-66.02;P = 0.043) were more subject to infestation from young buffalo and large herds. Furthermore, the hazard of toxoplasmosis was increased in winter especially among animals in contact with cats. It is therefore requisite to determine risk aspects to evaluate which mitigation, control, prevention and procedures should be carried out to diminish, control and prevent infestation with T. gondii and its propagation.

关键词： Toxoplasmosis Buffalo Local Seropositivity Iraq

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Some of the Chemical and Physical Characteristics of the Graff River in Kut City, Iraq

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Open Journal of Modern Hydrology 2024年第1期14卷 56-67页

作者： Salih Mahdi Ali Imad kazem Ali Ministry of Education Wasit Education Directorate Wasit Governorate Iraq Department of Animal Production College of Agriculture Sumer University Al-Rifai Iraq

Some of the chemical and physical water qualities of the Graff River in the city of Kut were studied, and for two sites of the river, One was at the Crimea site, the other in the Jihad district, and for the period from October/2018 to March/2019, Seven variables of river water have been analyzed: temperature PH, electrical conductivity, TDS, turbidity, alkaline, and chloride. The results showed that most of the chemical and physical water properties of the river were in normal proportions and did not rise, except for the turbidity, which was at a very high level, and that the pH values were close to the basal side. The results of the statistical analysis revealed positive significant relationships between the pH and (chloride and TDS). On the other hand, between electrical conductivity and both previous variables as well. And a negative significant connection between temperature and alkaline.

关键词： Graff River Kut City Iraq Chemical Characteristics Physical Characteristics

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Numerical study of n-heptane/benzene separation by thermal diffusion column

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Chinese Journal of Chemical Engineering 2019年第8期27卷 1745-1755页

作者： Neda Hashemipour Javad Karimi-Sabet kazem Motahari Saeed Mahruz Monfared Younes amini Mohammad Ali Moosavian Department of Chemical Engineering Faculty of EngineeringArak UniversityArakIran Material and Nuclear Fuel Research School(MNFRS) Nuclear Science and Technology Research InstituteTehranIran Department of Chemical and Petroleum Engineering Sharif University of TechnologyTehranIran Department of Chemical Engineering Isfahan University of TechnologyIsfahanIran School of Chemical Engineering Faculty of EngineeringUniversity of TehranTehranIran

In this article,numerical simulations are performed to investigate the performance of the thermal diffusion column for the separation of n-heptane/benzene *** present work tried to optimize column by analyzing significant parameters such as feed flow rate,temperature and *** order to obtain the hydrodynamic and temperature and mass distribution inside thermal diffusion column,computational fluid dynamic(CFD) method is applied to solve the Navier-Stocks *** simulations are conducted to study the main parameters in both stationary and time-dependent *** using the separation work unit as a function of cut,the optimal cut for maximum SWU occurs within a limited range of 0.47-0.5 for feed rate between 0.5 and 4 g min^-*** findings reveal that the optimum feed rate in the range of optimum cut is about 1 g min^-*** transient study,results show that the best cut for reaching to steady-state condition is θ=0.5.

关键词： Thermal diffusion column(TDC) Computational fluid dynamic Separative work unit n-Heptane/benzene separation

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A numerical study of self-gravitating protoplanetary disks

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Research in Astronomy and Astrophysics 2012年第3期12卷 331-344页

作者： kazem Faghei School of Physics Damghan University

The effect of self-gravity on protoplanetary disks is *** mechanisms of angular momentum transport and energy dissipation are assumed to be the viscosity due to turbulence in the accretion *** energy equation is considered in a situation where the released energy by viscosity dissipation is balanced with cooling *** viscosity is obtained by equality of dissipation and cooling functions,and is used to derive the angular momentum *** cooling rate of the flow is calculated by a prescription,du/dt = u/τ cool,where u and τ cool are the internal energy and cooling timescale,*** ratio of local cooling to dynamical timescales Ωτ cool is assumed to be a constant and also a function of the local *** solutions for protoplanetary disks show that in the case of Ωτ cool = constant,the disk does not exhibit any gravitational instability over small radii for a typical mass accretion rate,˙ M = 10 6 M yr 1,but when choosing Ωτ cool to be a function of temperature,gravitational instability can occur for this value of mass accretion rate or even less in small ***,by studying the viscosity parameter α,we find that the strength of turbulence in the inner part of self-gravitating protoplanetary disks is very *** results are qualitatively consistent with direct numerical simulations of protoplanetary ***,in the case of cooling with temperature dependence,the effect of physical parameters on the structure of the disk is *** solutions demonstrate that disk thickness and the Toomre parameter decrease by adding the ratio of disk mass to central object ***,the disk thickness and the Toomre parameter increase by adding mass accretion ***,for typical input parameters such as mass accretion rate 10 6 M yr 1,the ratio of the specific heat γ = 5/3 and the ratio of disk mass to central object mass q = 0.1,gravitational instability can occur over the whole radius of the disk excludin

关键词： accretion accretion disks—planetary systems:protoplanetary disks—planetary systems:formation

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A dynamical model for radiatively inefficient accretion flows with convection

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Research in Astronomy and Astrophysics 2013年第9期13卷 1075-1086页

作者： kazem Faghei School of Physics Damghan University

We explore the time evolution of radiatively-inefficient accretion flows. Since these types of accretion flows are convectively unstable, we also study the ef- fects of convection in the present model. The effects of convection are applied to equations describing angular momentum and energy. In analogy to the traditional c^- prescription, we introduce the convection parameter c^e to study the influences of con- vection on physical quantities. The model is studied in two cases： the transport of angular momentum due to convection inward and outward. We found the physical variables are sensitive to the parameter C^c and are also dependent on the direction of angular momentum that is transported by convection. As for angular momentum transfer inward, the accretion flow can be convectively dominated and radial infall velocity becomes zero. Moreover, we found the radial dependence of the density and radial velocity takes an intermediate place between steady state radiatively-inefficient accretion flow and steady state advection-dominated accretion flow. This property is in accord with direct numerical simulation of radiatively-inefficient accretion flows.

关键词： accretion accretion disks -- convection -- hydrodynamics

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An SPH simulation for cooling and self-gravitating protoplanetary disks

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Research in Astronomy and Astrophysics 2013年第2期13卷 170-178页

作者： kazem Faghei School of Physics Damghan University

We investigate the effects of the cooling function in the formation of clumps of protoplanetary disks using two-dimensional smoothed particle hydrody- namic simulations. We use a simple prescription for the cooling rate of the flow, du/dt = -u/τcool, where u and %ool are the internal energy and cooling timeseale, respectively. We assume the ratio of local＇cooling to dynamical timescale, Ωτcool =β, to be a constant and also a function of the local temperature. We found that for the constantβ and γ = 5/3, fragmentation occurs only forβ ≤ 7. However, in the case ofβ having temperature dependence and γ = 5/3, fragmentation can also occur for larger values ofβ. By increasing the temperature dependence of the cooling timescale, the mass accretion rate decreases, the population of clumps/fragments increases, and the clumps/fragments can also form in the smaller radii. Moreover, we found that the clumps can form even in a low mass accretion rate, ≤10-7M⊙yr-1, in the case of temperature-dependentβ. However, clumps form with a larger mass accretion rate, 〉 10-7M⊙ yr-1, in the case of constantβ.

关键词： accretion, accretion disks -- planetary systems protoplanetary disks -- planetary systems formation

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