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Artinianness and Attached Primes of Formal Local Cohomology Modules

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Algebra Colloquium 2014年第2期21卷 307-316页

作者： Mohammad Hasan Bijan-Zadeh Shahram rezaei Department of Mathematics Faculty of Science Payame Noor University Iran

Let a be an ideal of a local ring （R, m） and A4 a finitely generated R-modu｜e. In this paper we study the Artinianness properties of formal local cohomology modules and we obtain the lower and upper bounds for Artinianness of formal local cohomology modules. Additionally, we determine the set AttR a dim M（M） and we show that the set of all non-isomorphic formal local cohomology modules a dim M（M） is finite.

关键词： Artinianness properties attached primes formal local cohomology local co-homology

CO_2 reforming of methane over nickel catalysts supported on nanocrystalline MgAl_2O_4 with high surface area

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Journal of Natural gas Chemistry 2012年第2期21卷 200-206页

作者： Narges Hadian Mehran rezaei Zeinab Mosayebi Fereshteh Meshkani Institute of Nanoscience and Nanotechnology University of Kashan Catalyst and Advanced Materials Research Laboratory Chemical Engineering Department Faculty of Engineering University of Kashan

In this paper dry reforming of methane （DRM） was carried out over nanocrystalline MgAl2O4-supported Ni catalysts with various Ni loadings. Nanocrystalline MgAl2O4 spinel with high specific surface area was synthesized by a co-precipitation method with the addition of pluronic P123 triblock copolymer as surfactant, and employed as catalyst support. The prepared samples were characterized by X-ray diffraction （XRD）, N2 adsorption, H2 chemisorption, temperature-programmed reduction （TPR）, temperature-programmed oxidation （TPO）, temperature- programmed desorption （TPD） and transmission and scanning electron microscopies （TEM, SEM） techniques. The obtained results showed that the catalyst support has a nanocrystalline structure （crystal size： about 5 nm） with a high specific surface area （175 m2 g-1） and a mesoporous structure. Increasing in nickel content decreased the specific surface area and nickel dispersion. The prepared catalysts showed high catalytic activity and stability during the reaction. SEM analysis revealed that whisker type carbon deposited over the spent catalysts and increasing in nickel loading increased the amount of deposited carbon. The nickel catalyst with 7 wt% of nickel showed the highest catalytic activity.

关键词： dry reforming nickel catalysts magnesium aluminate

Energy supply for water electrolysis systems using wind and solar energy to produce hydrogen: a case study of Iran

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Frontiers in Energy 2019年第3期13卷 539-550页

作者： Mostafa rezaei Ali MOSTAFAEIPOUR Mojtaba QOLIPOUR Mozhgan MOMENI Industrial Engineering Department Yazd UniversityYazd ***Iran

Due to acute problems caused by fossil fuels that threaten the environment, conducting research on other types of energy carriers that are clean and renewable is of great importance. Since in the past few years hydrogen has been introduced as the future fuel, the aim of this study is to evaluate wind and solar energy potentials in prone areas of Iran by the Weibull distribution function (WDF) and the Angstrom-Prescott (AP) equation for hydrogen production. To this end, the meteorological data of solar radiation and wind speed recorded at 10 m height in the time interval of 3 h in a five-year period have been used. The findings indicate that Manjil and Zahedan with yearly wind and solar energy densities of 6004 (kWh/m2) and 2247 0cWh/m2), respectively, have the greatest amount of energy among the other cities. After examining three different types of commercial wind turbines and photovoltaic (PV) systems, it becomes clear that by utilizing one set of gamesa g47 turbine, 91 kg/d of hydrogen, which provides energy for 91 car/week, can be produced in Manjil and will save about 1347 L of gasoline in the week. Besides, by installing one thousand sets of X21-345 PV systems in Zahedan, 20 kg/d of hydrogen, enough for 20 cars per week, can be generated and 296 L of gasoline can be saved. Finally, the RETScreen software is used to calculate the annual CO2 emission reduction after replacing gasoline with the produced hydrogen.

关键词： wind energy solar energy water electrolysis hydrogen production Weibull distribution function (WDF) Angstrom丒Prescott (AP) equation

Dietary supplementation with branchedchain amino acids enhances milk production by lactating sows and the growth of suckling piglets

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Journal of Animal Science and Biotechnology 2022年第6期13卷 1857-1870页

作者： Reza rezaei Ana San gabriel guoyao Wu Department of Animal Science Texas A&M UniversityCollege StationTX 77843USA Ajinomoto Co. Inc1-15-1 KyobashiChuokuTokyo 104-8315Japan

Background:Under current dietary regimens,milk production by lactating sows is insufficient to sustain the maximal growth of their *** precursors of glutamate and glutamine as well as substrates and activators of protein synthesis,branched-chain amino acids(BCAAs)have great potential for enhancing milk production by ***:Thirty multiparous sows were assigned randomly into one of three groups:control(a corn-and soybean meal-based diet),the basal diet+1.535%BCAAs;and the basal diet+3.07%*** ratio(g/g)among the supplemental L-isoleucine,L-leucine and L-valine was 1.00:2.56:*** were made isonitrogenous by the addition of appropriate amounts of *** sows had free access to drinking water and their respective *** number of live-born piglets was standardized to 9 per sow at d 0 of lactation(the day of parturition).On d 3,15 and 29 of lactation,body weights and milk consumption of piglets were measured,and blood samples were obtained from sows and piglets 2 h and 1 h after feeding and nursing,***:Feed intake did not differ among the three groups of *** of asparagine,glutamate,glutamine,citrulline,arginine,proline,BCAAs,and many other amino acids were greater(Pglets than those in the control *** with the control,dietary supplementation with 1.535%and 3.07%BCAAs increased(Pglutamate plus glutamine,aspartate plus asparagine,and many other amino acids in milk;milk production by 14%and 21%,respectively;daily weight gains of piglets by 19%and 28%,respectively,while reducing preweaning mortality rates by 50%and 70%,***:Dietary supplementation with up to 3.07%BCAAs enhanced milk production by lactating sows,and the growth and survival of their piglets.

关键词： Branched-chain amino acids Lactation Milk synthesis Milk yield Neonatal growth Sow

Cross-focusing of two chirped gaussian laser beams and THz wave generation in plasmas of multi-ion species under a weakly relativistic and ponderomotive regime

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Plasma Science and Technology 2022年第10期24卷 1-11页

作者： M R JAFARI MILANI S rezaei M J JAFARI Photonics and Quantum Technologies Research School Nuclear Science and Technology Research InstituteTehran 14665-678Iran Plasma and Fusion Research School Nuclear Science and Technology Research InstituteTehran 14399-51113Iran

The generation of terahertz(THz)waves via the beating of two high-intensity chirped gaussian lasers in a multi-ion-species plasma is numerically studied by taking into account the weak relativistic and ponderomotive regime of *** coupled differential equations for beamwidth parameters are extracted by introducing the dielectric function of such plasma and using WKB and paraxial ray *** amplitude of THz radiation at beat frequency resulting from the nonlinear current density induced by the beat ponderomotive force of the cross-focusing of beams was *** impacts of the chirp frequency parameter,initial laser intensity and initial ionic species density(specifically,the presence of singly and doubly charged ions)in the plasma on THz generation were *** numerical results reveal that THz radiation generation strongly depends on the chirp frequency parameter.A specific range of chirp frequencies exists for self-focusing as well as THz generation with a'turning point',where the THz emission reaches its maximum *** results show that the strength of self-focusing and consequently the generated THz radiation are reduced by increasing the density of doubly charged ionic species in the plasma due to the suppression of the nonlinear effects.

关键词： laser–plasma interaction THz generation chirped gaussian laser beams

Syngas production by combined carbon dioxide reforming and partial oxidation of methane over Ni/α-Al_2O_3 catalysts

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Journal of Natural gas Chemistry 2010年第6期19卷 638-641页

作者： Armin Moniri S.Mehdi Alavi Mojgan rezaei Reaction Engineering Research Lab. School of Chemical EngineeringIran University of Science and Technology(IUST)

Ni/α-Al2O3 catalysts were found to be active in the temperature range 600 ～ 900℃ for both CO2 reforming and partial oxidation of *** effects of Ni loading,reaction temperature and feed gas ratio for the combination of CO2 reforming and partial oxidation of CH4 over Ni/α-Al2O3 were *** of xwt%Ni/α-Al2O3（x=2.5,5,8 and 12） were prepared by wet impregnating the calcined support with a solution of nickel *** patterns and activity tests have verified that the 5wt%Ni/α-Al2O3 was the most active catalyst,as compared with the other prepared catalyst *** increase of the Ni loading to more than 5wt% led to a reduction in the Ni *** addition,by combining the endothermic carbon dioxide reforming reaction with the exothermic partial oxidation reaction,the loss of catalyst activity with time on stream was reduced with the amount of oxygen added to the feed.

关键词： O2 carbon dioxide (CO2) methane Ni/α-Al2O3 catalysts combined reaction

Sustainability assessment of potato fields using the DEXi decision support system in Hamadan Province, Iran

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Journal of Integrative Agriculture 2018年第11期17卷 2583-2595页

作者： Mohammed Ebrahim rezaei Morteza Barmaki Hadi Veisi Department of Agronomy and Plant Breeding University of Mohaghegh Ardabili Environmental Sciences Research Institute Shahid Beheshti University

Potato is a staple food crop and the most important agricultural commodity, which critically affects food security and economic stability in Hamadan Province, Iran. Ex-ante sustainability appraisal of new cropping systems and their comparisons with conventional systems can increase the efficiencies of innovations and changes within the production process. This study aimed to explore the sustainability levels of potato cropping systems in Hamadan Province, Iran. To this end, DEXi methodology was developed for the sustainability assessment of the cropping systems. For assessing the three dimensions of environmental, economic, and social sustainability in the four systems of traditional potato system （TPS）, Quasi-industrial potato system （QIPS）, industrial potato system （IPS）, and government-promoted potato system （gPPS）, five groups of features were utilized：（1） irrigation method; （2） seed placement; （3） farm machinery use; （4） agrochemical use; and （5） rotation. The impact a^sessments of the cropping systems were based on two, three, and two groups of ecological, social, and economic indicators, respectively. Employment, supply chain, protection, operational difficulty, productivity, profitability, input use, and biodiversity resulted in 21 basic indicators and 13 aggregated indicators, by which the cropping systems were described. The results revealed that gPPS with distinctive economic and social profiles could have a better overall sustainability despite the fact that some indicators like biodiversity could be negatively affected. Finally, three strategies were recommended for the sustainability of gPPS as follows： biodiversity enhancement, input substitution, and integrated water management.

关键词： agricultural sustainability multi-criteria potato

Colostrum and milk performance,and blood immunity indices and minerals of Holstein cows receiving organic Mn,Zn and Cu sources

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Animal Nutrition 2020年第1期6卷 61-68页

作者： Habiballah Roshanzamir Javad rezaei Hassan Fazaeli Department of Animal Science Faculty of AgricultureTarbiat Modares UniversityP.O.Box 14U5-336TehranIran Animal Science Research Institute of Iran Agricultural ResearchEducation and Extension Organization(AREEO)Karaj.***Iran

Effects of supplementing the basal diets with Mn,Zn and Cu,as sulphate,glycine or methionine salts,on colostrum and milk performance,some blood immunity indices and blood minerals of pre-and postpartum Holstein cows were *** cows in different groups received:1)a diet without supplementary Mn,Zn and Cu(control),2)a diet containing Mn,Zn and Cu sulphates,3)a diet containing Mn,Zn and Cu glycine,or 4)a diet containing Mn,Zn and Cu methionine with 10 cows per group from d 60 before calving(dry period)to d 100 of *** matter intake(DMI),dry matter digestibility(DMD),colostrum and milk performance,milk somatic cell count(SCC),blood and milk total antioxidant capacity(TAC),immunoglobulin M(IgM)and immunoglobulin A(IgA),and blood Mn,Zn and Cu were *** supplementation with Mn,Zn and Cu as methionine,glycine or sulphate salts had positive effects on DMD,DMI,colostrum and milk performance,milk SCC,and blood Mn and *** of Mn,Zn and Cu in diets could increase(PgA and IgM in the cows and their new-born *** were no differences in DMI,DMD,colostrum and milk yields,milk SCC,blood Mn(except d 50 postpartum),Zn and Cu and TAC(except d 50 postpartum)among the organic and inorganic minerals-supplemented groups(P>0.05),however,the blood concentrations of IgA(except d 1 postpartum)and IgM in the cows supplemented with organic Mn,Zn and Cu were higher(Pg the sulphate sources of ***,dietary supplementation of Mn,Zn and Cu as methionine,glycine or sulphate salts can improve colostrum and milk performance,blood Zn and Mn and immunity indices in Holstein cows and their new-born ***,the organic sources of Mn,Zn and Cu have advantage over the sulphate forms in terms of the blood immunoglobulins.

关键词： Antioxidant status Cattle Immunity Organic trace minerals Performance

Thermodynamic analysis of combined reforming process using gibbs energy minimization method: In view of solid carbon formation

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Journal of Natural gas Chemistry 2012年第6期21卷 694-702页

作者： Behzad Nematollahi Mehran rezaei Ebrahim Nemati Lay Majid Khajenoori Catalyst and Advanced Materials Research Laboratory Chemical Engineering Department Faculty of Engineering University of Kashan Institute of Nanoscience and Nanotechnology University of Kashan Energy Research Institute University of Kashan

Thermodynamic analysis was applied to study combined partial oxidation and carbon dioxide reforming of methane in view of carbon formation. The equilibrium calculations employing the gibbs energy minimization were performed upon wide ranges of pressure （1-25 atm）, temperature （600-1300 K）, carbon dioxide to methane ratio （0-2） and oxygen to methane ratio （0-1）. The thermodynamic results were compared with the results obtained over a Ru supported catalyst. The results revealed that by increasing the reaction pressure methane conversion decreased. Also it was found that the atmospheric pressure is the preferable pressure for both dry reforming and partial oxidation of methane and increasing the temperature caused increases in both activity of carbon and conversion of methane. The results clearly showed that the addition of O2 to the feed mixture could lead to a reduction of carbon deposition.

关键词： combined reforming carbon deposition chemical equilibrium gibbs energy minimization method thermodynamic analysis