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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

Numerical modeling of nonlinear sloshing of liquid in a container coupled with barge subjected to regular excitation

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journal of Hydrodynamics 2019年第5期31卷 999-1010页

作者： j.j.stephen s.A.sannasiraj V.sundar Department of Ocean Engineering Indian Institute of Technology MadrasChennai 600036India

The sloshing phenomenon of liquid in a partially filled tank mounted rigidly within a barge exposed to regular wave field has been considered for numerical *** paper details the numerical scheme developed in time domain to study the interaction of wave induced barge motion with sloshing oscillations in a partially filled *** sloshing time history results obtained from the numerical scheme adopted are validated with experimental measurements of Nasar et al.(2008)The harmonics present in the sloshing oscillation for the liquid fill levels(25%,50%and 75%)have been analyzed.

关键词： Floating barge sloshing finite element method impulse response function coupled analysis

Effect of dietary near ideal amino acid profile on heat production of lactating sows exposed to thermal neutral and heat stress conditions

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journal of Animal science and Biotechnology 2021年第2期12卷 739-754页

作者： s.Zhang j.s.johnson N.L.Trottier Department of Animal science Michigan State UniversityEast Lansing 48824USA UsDA-ARs Livestock Behavior Research Unit West Lafayette 47907USA

Background:Reduced protein diet manifested potential to mitigate heat production based on the concept of ideal amino acid *** hypothesis of this study was that lactating sows fed a low crude protein(LCP)diet with supplemental amino acid produce less heat compared to those fed a high crude protein(HCP)diet under both thermal neutral(TN)and heat stress(Hs)***:Thirty-two lactating sows were allotted to HCP(193 g CP/kg)and LCP(140 g CP/kg)diets under thermal neutral(TN,21±1.5°C)or cycling heat stress(Hs,32±1.5°C daytime and 24±1.5°C nighttime)*** contained 0.90%sID lysine and 10.8 Mj/kg net *** pressure indirect calorimeters were used to measure gas exchange in individual sows with litters,and individual piglets on days 4,8,14 and *** and litter weights were recorded on days 1,10 and ***:sow total heat production(THP)was calculated by subtracting litter THP from sow+litter THP based on *** BW and body protein(BP)loss was greater for LCP diet compared to HCP diet in peak lactation(Pspectively)and throughout the entire lactation period(Pspectively)under Hs ***-stressed sows fed HCP diet had higher(Pspiration rate at 07:00(Psows fed HCP *** sows fed LCP diet,those under Hs tended to have higher(P=0.098)rectal temperature at 13:00 and had higher(Pspiration rate at 07:00,13:00 and 19:00 compared to TN *** relationship between daily THP and days in lactation of sows fed LCP diet was quadratic(Pscending trend until day 14 and a descending trend from days 14 to *** fed LCP diet had lower daily THP at day 18(Pse fed the HCP diet under Hs ***:Reduction in THP in sows fed LCP diet was largely associated with THP on day 18 of lactation under Hs *** LCP die

关键词： Amino acid Heat stress Lactating sows Low protein diet Total heat production

soaking Induced Changes in Chemical Composition, Glycemic Index and starch Characteristics of Basmati Rice

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Rice science 2015年第5期22卷 227-236页

作者： s.j.KALE s.K.jHA G.K.jHA j.P.sINHA s.B.LAL Division of Food science and Post Harvest Technology Indian Agricultural Research Institute Division of Agricultural Economics Indian Agricultural Research Institute Division of Agricultural Engineering Indian Agricultural Research Institute Division of Computer Applications Indian Agricultural Research Institute

An attempt was made to determine the qualitative changes in basmati rice （Pusa Basmati 1121, PBl121） during soaking at 40 ℃ to 80 ℃. soaking temperature had significant effect （a = 0.01） on chemical composition, glycemic index and starch characteristics of rice. starch content, apparent amylose content, crude protein content and crude fat content in un-soaked rice were found to be 73.24%, 27.26%, 8.79% and 2.56%, respectively, but differences in these traits were observed after soaking. Amylose to amylopectin ratio （Am/Ap） decreased from 0.59 to 0.52 （soaked at 80 ℃）. Crude fibre and crude ash contents increased after soaking. The mineral composition （K, P, s, Ca, Mg, Mn, Fe, Cu and Zn） in soaked rice was found to be 16.46% higher than un-soaked rice at the same degree of polishing. Glycemic index of un-soaked rice was found to be 58.41, but decreased to 54.31 after soaking at 80 ℃. Pasting properties, scanning electron microscope images, and X-ray diffractograms suggested partial gelatinization of starch in the temperature range of 60 ℃ to 80 ℃. Based on qualitative changes in rice （apparent amylose content, Am/Ap ratio and crystallinity rate）, it was concluded that intermediate soakincl temperatures （60 ℃ to 70 ℃） would be useful for soaking of PB1121.

关键词： basmati rice soaking glycemic index starch characteristic temperature chemicalcomposition crystallinity

Optimum blending of iron ore from Choghart stockpiles by using goal programming

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journal of Central south University 2012年第4期19卷 1081-1085页

作者： j.Gholamnejad s.Kasmaee Department of Mining and Metallurgical Engineering Yazd UniversityYazd 89195-741Iran

Iron and steel industry is an important sector of Iran's *** iron ore mine is an important iron ore producer of Iran steel *** contained in the iron ore concentrates of Choghart mine has a detrimental effect on the steel making process,whereby this causes cracks to form in the refractory lining of blast *** the past,about 1.43 Mt of low-grade and 4.53 Mt of high-phosphorous materials had been transported to low grade and high phosphorous stockpiles,respectively,for future *** a result of the progressive depletion of high-grade ore and establishment of beneficiation plant in Choghart,exploitation of these two stockpiles in this mine became an important *** this work,a linear goal programming(GP) model was developed in order to determine the optimum iron ore blend in terms of quality from low grade and high phosphorous stockpiles of Choghart *** model was solved by the sOLVER V.9 *** show that feeding with acceptable quality(w(Fe)≥50% and w(P)≤1.2%,mass fraction) materials can be blended from stockpiles that satisfy the needs of the Choghart processing line.

关键词： processing plant short term production scheduling goal programming stockpile

The search for the Quantum spin Liquid in Kagome Antiferromagnets

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Chinese Physics Letters 2019年第5期36卷 5-6页

作者： j.-j.Wen Y.s.Lee stanford Institute for Materials and Energy sciences SLAC National Accelerator Laboratory Department of Applied Physics Stanford University

A quantum spin liquid (QsL) is an exotic quantum ground state that does not break conventional symmetries and where the spins in the system remain dynamic down to zero temperature. Unlike a trivial paramagnetic state,... 详细信息

关键词： The search for the Quantum spin Liquid in Kagome Antiferromagnets Zn

Implementing the Node Based smoothed Finite Element Method as User Element in Abaqus for Linear and Nonlinear Elasticity

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Computers, Materials & Continua 2019年第8期61卷 481-502页

作者： s.Kshrisagar A.Francis j.j.Yee s.Natarajan C.K.Lee Integrated Modelling and simulation Lab Department of Mechanical EngineeringIndian Institute of Technology MadrasChennai600036India The Department of Architectural Engineering Dong-A UniversityS04-0302Engineering 237Nakdongdaero 550beon-gilSaha-guBusan49315Korea National Research Center for Disaster-free&safe Ocean City Dong-A UniversityS04-0311-3Engineering 237Nakdong-daero 550beon-gilSaha-guBusan49315Korea

In this paper,the node based smoothed-strain Abaqus user element(UEL)in the framework of finite element method is *** basic idea behind of the node based smoothed finite element(NsFEM)is that finite element cells are divided into subcells and subcells construct the smoothing domain associated with each node of a finite element cell[Liu,Dai and Nguyen-Thoi(2007)].Therefore,the numerical integration is globally performed over smoothing *** is demonstrated that the proposed UEL retains all the advantages of the NsFEM,i.e.,upper bound solution,overly soft stiffness and free from locking in compressible and nearly-incompressible *** this work,the constant strain triangular(CsT)elements are used to construct node based smoothing domains,since any complex two dimensional domains can be discretized using CsT *** additional challenge is successfully addressed in this *** efficacy and robustness of the proposed work is obtained by several benchmark problems in both linear and nonlinear *** developed UEL and the associated files can be downloaded from https://***/nsundar/NsFEM.

关键词： smoothed finite element method(sFEM) node based sFEM(NsFEM) linear and nonlinear elasticity Abaqus UEL(user elements) compressible and nearlyincompressible materials

Improved mechanical properties of siC fiber reinforced silica-based ceramic cores fabricated by stereolithography

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journal of Materials science & Technology 2022年第21期116卷 161-168页

作者： W.Zheng j.M.Wu s.Chen K.B.Yu j.Zhang Y.s.shi state Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China Engineering Research Center of Ceramic Materials for Additive Manufacturing Ministry of EducationWuhan 430074China

silica-based ceramic cores have been widely used to fabricate aero-engine hollow blades due to their moderate high temperature mechanical properties and excellent *** this study,silica-based ceramics with siC fiber addition were prepared via stereolithography,and the influence of siC fiber content on mechanical properties of the obtained silica-based ceramics was *** the increase of siC fiber content,linear shrinkage gradually decreased,while room temperature flexural strength and high temperature flexural strength first increased and then *** siC fiber content increased to 4.0 wt%,linear shrinkage was reduced to 0.62%resulting from the oxidation of ***,room temperature flexural strength was improved from 11.79 MPa to 23.83 MPa and high temperature flexural strength was enhanced from 15.64 MPa to 34.62 MPa with 4.0 wt%siC fiber addition due to the reinforcement of fibers and the enhancedβ-cristobalite content,which meets the need of ceramic ***,it demonstrates the capability of fabricating high-performance and high-precision silica-based ceramic cores reinforced by siC fibers via stereolithography for rapid manufacturing of hollow blades.

关键词： silica-based ceramic cores stereolithography siC fiber Mechanical properties Hollow blades

Accuracy details in realistic CFD modeling of an industrial centrifugal pump in direct and reverse modes

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journal of Thermal science 2010年第6期19卷 491-499页

作者： j.C. Páscoa F. j. silva j.s. Pinheiro D.j. Martins Department of Electromechanical Engineering Center for Aerospace Sciences and Technology University of Beira Interior EFAFLU Bombas e Ventiladores s.A. R. S. Brás 269 Apartado 23 4494-909 Póvoa do Varzim Portugal

Numerical computation of the flowfield inside a pump is herein used as a numerical laboratory, subject to the limitations of modeling assumptions and to experimental verification. A numerical computation of the flow inside a real industrial centrifugal pump is performed that includes a very sophisticated geometry. Conversely to other computations, in this test case no simplification of the geometry was introduced. Numerical computations are obtained using spalart-Allmaras turbulence model. A detailed analysis of the turbulent flowstructure is performed for the design point and two off design conditions. Additional computations were performed in order to compare the numerical and experimental pump characteristics; these were obtained under normalized testing conditions. Further computations are presented for the pump working in reverse turbine mode (PAT). Detailed analyses of the flow allow a comparison of the internal flow losses when the pump is operating in direct and reverse mode. This is also useful to help in the selection of an adequate pump geometry that can work in both modes with best efficiency.

关键词： centrifugal pump impeller turbulence modeling spalart-Allmaras PAT