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Frontiers of structural and civil Engineering 2024年第2期18卷 170-183页

作者： r.mOHANA s.m.Leela BHAraTHI Department of civil Engineering Mepco Schlenk Engineering CollegeSivakasi 626123India

The hazardous environmental effects of greenhouse gas emissions and climate change demand alternative sources for cementitious materials in the construction *** development of geopolym.r structures provides a way of producing 100%cement-free *** this research work,a novel and simple way of deriving nano particles from waste fly ash particles is *** effect of adding the synthesized nano fly ash particles as a filler medium in geopolym.r m.rtars was investigated by considering strength and durability *** optimization was done by using regression analysis on the geopolym.r m.rtar and the impact of adding nano fly ash particles was studied by varying different percentages of addition ranging from 0 to 7.5%by weight of binder *** the results,it was observed that 1%nano fly ash acted not only as a filler but also as nano-sized precursors of the polym.rization process,resulting in denser geopolym.r *** can explain the extraordinary gain in strength of 72.11 mPa as well as the denser core with negligible level of chloride ion penetration,making the material suitable for the development of structures susceptible to m.rine environment.

关键词： geopolym.r nano fly ash chloride ion penetration durability polym.rization fillers

Kinematic analysis of flexible bipedal robotic systems

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Applied mathematics and mechanics(English Edition) 2024年第5期45卷 795-818页

作者： r.FAZEL A.m.sHAFEI s.r.NEKOO Department of mechanical Engineering Shahid Bahonar University of KermanKerman ***Iran Departamento de Ingenieria de sistemas y Automatica Escuela Técnica Superior de IngenieriaUniversidad de SevillaSeville 41092Spain

In spite of its intrinsic complexities,the passive gait of bipedal robots on a sloping ramp is a subject of interest for num.rous *** distinguishes the present research from similar works is the consideration of flexibility in the constituent links of this type of robotic *** is not a far-fetched assumption because in the transient(impact)phase,due to the impulsive forces which are applied to the system,the likelihood of exciting the vibration modes increases ***,the human leg bones that are involved in walking are supported by viscoelastic muscles and ***,for achieving m.re exact results,it is essential to model the robot links with viscoelastic *** this end,the Gibbs-Appell formulation and Newton's kinematic impact law are used to derive the most general form of the system's dynamic equations in the swing and transient phases of *** most important issue in the passive walking motion of bipedal robots is the determination of the initial robot configuration with which the system could accomplish a periodic and stable gait solely under the effect of gravitational *** extremely unstable nature of the system studied in this paper and the vibrations caused by the impulsive forces induced by the impact of robot feet with the inclined surface are some of the very serious challenges encountered for achieving the above-mentioned *** overcome such challenges,an innovative method that uses a combination of the linearized equations of motion in the swing phase and the algebraic motion equations in the transition phase is presented in this paper to obtain an eigenvalue *** solving this problem,the suitable initial conditions that are necessary for the passive gait of this bipedal robot on a sloping surface are *** effects of the characteristic parameters of elastic links including the modulus of elasticity and the Kelvin-Voigt coefficient on the walking stability of this type of

关键词： bipedal robot flexible link swing phase transient phase eigenvalue problem Kelvin-Voigt coefficient

cr-induced fusion reactions to synthesize superheavy elements

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Nuclear science and Techniques 2024年第5期35卷 122-130页

作者： s.madhu H.c.manjunatha N.sowmya B.m.rajesh L.seenappa r.s.susheela Department of Physics R V College of EngineeringBangalore 560074India Visvesvaraya Technological University BelagaviKarnataka 590018India Department of Physics Government First Grade CollegeSrinivasapurKarnataka 563135India Department of Physics Government First Grade CollegeDevanahallyKarnataka 562110India Department of Physics Government First Grade CollegeMulbagalKarnataka 563131India Department of Physics Government First Grade collegeNanjangudOoty RoadMysore 571301India

We investigated ^(50,52-54)cr-induced fusion reactions for the synthesis of the superheavy element in the 104≤Z≤122 *** cross sections produced in this investigation using ^(54)cr projectiles were compared with those obtained in prior *** estimated cross sections from this analysis are consistent with the findings of prior *** the current study,the predicted cross section was found to be 42fb at 236 meV for ^(53)cr+^(243)Am,23.2 fb at 236 meV for ^(54)cr+^(247)cm,95.6 fb at 240 meV for ^(53)cr+248Bk,and 1.33 fb at 242 meV for ^(53)cr+***,these projected cross sections with excitation energy and beam energy will be useful in future cr-induced fusion reaction investigations.

关键词： Fusion cross sections compound nucleus formation probability survival probability Evaporation residue cross sections

structural effects induced by dialysis-based purification of carbon nanomaterials

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Nano materials science 2024年第4期6卷 475-483页

作者： A.D.Veloso A.m.Ferraria A.m.Botelho do rego A.s.Viana A.J.s.Fernandes A.J.Fielding r.A.Videira m.c.Oliveira cQ-Vr and chemistry Department University of Trás-os-Montes e Alto Douro BsIrG iBB-Institute for Bioengineering and BiosciencesDepartment of Chemical Engineeringand Associate Laboratory i4HB-Institute for Health and BioeconomyInstituto Superior TécnicoUniversidade de Lisboa centro de Química Estrutural Institute of Molecular SciencesDepartamento de Química e BioquímicaFaculdade de CiênciasUniversidade de Lisboa I3N and Physics Department University of AveiroCampus de Santiago Faculty of science Pharmacy and Biomolecular SchoolLiverpool John Moores University rEQUImTE/LAQV Laborat orio de FarmacognosiaDepartamento de QuímicaFaculdade de Farm aciaUniversidade do Porto

Dialysis plays a crucial role in the purification of nanomaterials but its impact on the structural properties of carbon nanomaterials was never ***,a carbon-based nanomaterial generated electrochemically in potassium phosphate buffer,was characterized before and after dialysis against pure *** is shown that dialysis affects the size of the carbon domains,structural organization,surface functionalization,oxidation degree of carbon,and grade of ***,dialysis drives the nanomaterial organization from discrete roundish carbon domains,with sizes ranging from 70 to 160 nm,towards linear stacking structures of small nanoparticles （m）.In parallel,alcohol and ether （epoxide） surface groups evolve into m.re oxidized carbon groups （e.g.,ketone and ester groups）.Investigation of the as-prepared nanomaterial by electron paramagnetic resonance （EPr） revealed a resonance signal consistent with carbon-oxygen centred ***,this study brings to light the selective affinity of the carbon nanomaterial under study to capture Na+ions,a property greatly enhanced by the dialysis process,and its high ability to trap oxygen,particularly before *** findings open new perspectives for the application of carbon-based nanomaterials and raise awareness of the importance of structural changes that can occur during the purification of carbon-based nanomaterials.

关键词： Nanocarbon surface functionalization Nmr XPs Hydrophilic carbon Paramagnetic

Enhancement of coercivity,permeability,and dielectric properties of co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites for mem.ry and high frequency devices

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Journal of rare Earths 2024年第6期42卷 1128-1135,I0005页

作者： I.sardar m.D.Hossain m.s.sikder m.N.I.Khan m.r.rahman Physics Discipline Khulna UniversityKhulna9208Bangladesh Department of Physics Khulna University of Engineering&TechnologyKhulna9203Bangladesh Department ofcomputer science and Engineering Northern University of Business&Technology KhulnaKhulna9100Bangladesh material science Division Atomic Energy CentreDhaka1000Bangladesh

spinel cubic ferrites have huge applications in me m.ry and high frequency *** the im.rovement of these modern devices,the magnetic coercivity,permeability,and dielectric properties of a ferrite are the important *** article focuses on im.roving the magnetic coercivity,magnetic permeability,and dielectric properties of co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites,where x=0.00,0.06,and *** X-ray diffraction(XrD),Fourier transform infrared spectroscopy(FTIr),field emission scanning electron microscopy(FEsEm),energy dispersive X-ray(EDX),vibrating sample magnetometer(Vsm),and an impedance analyzer were used to characterize the structural,magnetic,and dielectric properties of the *** XrD patterns indicate the formation of spinel cubic structure of the samples with a secondary peak(EuFeO_(3))for Eu doped *** densities and porosities of the samples follow an inverse trend,where the doped samples’lattice parameters are increased with the increment of rare earth Eu *** FTIr analysis also proves the spinel cubic phase of the *** average grain size of the ferrites is obtained via FEsEm images,and it is increased from 121 to 198 *** analysis confirms that doping of the Eu content also changes other hysteresis loop properties of co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ***,the coercivity of the Eu doped samples is greater than that of the mother alloy(x=0.00).The EDX study shows that there is no impurity contamination in the *** permeability and dielectric measurements show an im.roved quality factor of the Eu-doped samples with low magnetic and dielectric *** dependent resistivity and impedance analysis also show the im.roved *** the observed properties of the samples,all the investigated ferrites might be strong candidates for potential applications in mem.ry devices,magnetic sensors,and high frequency applications.

关键词： Ferrites raree arths coercivity Permeability EDX resistivity

complexed amino acid minerals vs. bis-glycinate chelated minerals:Impact on the performance of old laying hens

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Animal Nutrition 2024年第1期16卷 395-408页

作者： m.rcos J.B.santos m.ria c.m.m.Ludke Leandro m.silva carlos B.V.rabello m.rcia r.Barros Fabiano s.costa clariana s.santos Jamille s.s.Wanderley Department of Animal science Rural Federal University of Pernambuco Department of Veterinary science Rural Federal University of Pernambuco

The present study was to evaluate the effect of trace minerals(Zn, mn, and cu) from complexed amino acid minerals(ZmcAA) and bis-glycinate chelated minerals(ZmcGly) in laying hen diets on performance,internal and external egg quality, yolk mineral deposition, intestinal m.rphometry, and bone characteristics. From 78 to 98 weeks of age, 400 White LsL-Lite strain laying hens were distributed in a randomized design with 4 treatments with 10 replicates per treatment. Treatments were distributed in a 2 ×2 factorial arrangement using either Zn, mn, and cu of ZmcAA or ZmcGly source at 2 levels: low(20, 20,and 3.5 mg/kg of Zn, mn, and cu, respectively) or high(40, 40, and 7 mg/kg of Zn, mn, and cu,respectively). The analysis of variance was performed, and in cases where differences were observed, the means were compared using Tukey?s test(P source and level of trace mineral supplementation had a significant impact on the performance of laying hens. Hens fed ZmcAA had higher egg production(P = 0.01), egg weight(P = 0.02), egg mass(P = 0.01), and lower feed conversion ratio(P =0.05) compared to those fed ZmcGly. The ZmcAA supplementation showed higher albumen height(P =0.01), albumen weight(P = 0.01), and eggshell thickness(P sition of Zn(P mn(Pcu(P s greater for hens received ZmcAA. Tibia weight(P = 0.04)and bone densitometry(P re higher with ZmcAA supplementation. In the small intestine, ZmcAA resulted in longer villi(P = 0.02) and shorter crypt depth(P = 0.01) in the *** and ileum measurements were influenced by the level and source of trace minerals(P s fed ZmcAA exhibited superior performance, egg quality, deposition of trace minerals in the egg yolk, and bone density compared to hens fed ZmcGly. In this study, older laying hens supplemented with ZmcAA at lower levels demonstrated adequate levels of supplementation.

关键词： Bis-glycinates metal-amino acids radiodensity Trace minerals

Engineering of efficient visible light photocatalysts:Ti_(1-x+y)cu_(x)La_(y)O_(2)(x=0.03;y=0,0.005,0.01) compositions

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Journal of rare Earths 2024年第3期42卷 497-505,I0003页

作者： s.m.Yakout A.m.Youssef Inorganic chemistry Department National Research Centre(NRC)El Buhouth StDokkiCairo12622Egypt

In dye-photocatalysis, widening the wavelengths absorption range of catalysts as well as aborting the recombination of the photoexcited charge carriers(electrons-holes pairs) are of paramount *** the current study, we report the photocatalytic characteristics of four compositions composed of TiO_(2),Ti_(0.97)cu_(0.03)O_(2), Ti_(0.965)cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)cu_(0.03)La_(0.01)O_(2)powders for two harmful dyes(congo red and methylene blue). The X-ray diffraction technique verified the configuration of mixed anatase and rutile phases in pure TiO_(2)and Ti_(0.97)cu_(0.03)O_(2)powders while Ti_(0.965)cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)cu_(0.03)La_(0.01)O_(2)powders possess anatase phase only. The changes of the band gap structure and dimensions of the unit cell volume of TiO_(2)confirm the substitution of Ti^(4+)sites by cu^(2+)and La^(3+)ions. rem.rkable widening of wavelengths absorption with formation of long absorption tails were found in TiO_(2)(3.13 e V) through insertion of La^(3+)plus cu^(2+)ions. Ti_(0.965)cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)cu_(0.03)La_(0.01)O_(2)samples exhibit a visible light band gap of 2.3 and 2.7 e V, respectively. Based on sEm images, incorporation of cu^(2+)and La^(3+)ions influences the surface m.rphology of TiO_(2). The resulting Ti_(0.97)cu_(0.03)O_(2), Ti_(0.965)cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)cu_(0.03)La_(0.01)O_(2)powders present enhanced photocatalytic activity towards congo red dye degradation compared to pure one under natural solar spectrum. The best Ti_(0.96)cu_(0.03)La_(0.01)O_(2)catalyst exhibits superior photocatalytic activity of 96% for 10 ppm cr dye in 20 min as well as above average photocatalytic efficiency of 63% for 30 ppm cr dye in 120 min. As well, it showed acceptable photodegradation activity of 52% for 30 ppm mB solution in 140 min of sunlight irradiation. The heightened photodegradation efficiency of Ti_(0.96)cu_(0.03)La_(0.01)O_(2)catalyst can be clarified in terms of higher ch

关键词： semiconductor TiO_(2) rare earths congo red methylene blue solar spectrum Photodegradation

Nonlinear dynamic modeling of planar moving Timoshenko beam considering non-rigid non-elastic axial effects

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 479-496页

作者： m.ABBAsI GAVArI m.r.HOmAEINEZHAD Faculty of mechanical Engineering K.N.Toosi University of TechnologyTehran 19991-43344Iran

Due to the importance of vibration effects on the functional accuracy of mechanical systems,this research aims to develop a precise model of a nonlinearly vibrating single-link mobile flexible *** manipulator consists of an elastic arm,a rotary motor,and a rigid carrier,and undergoes general in-plane rigid body motion along with elastic transverse *** accurately model the elastic behavior,Timoshenko’s beam theory is used to describe the flexible arm,which accounts for rotary inertia and shear deformation *** applying Newton’s second law,the nonlinear governing equations of motion for the manipulator are derived as a coupled system of ordinary differential equations(ODEs)and partial differential equations(PDEs).Then,the assumed mode method(Amm)is used to solve this nonlinear system of governing equations with appropriate shape *** assumed modes can be obtained after solving the characteristic equation of a Timoshenko beam with clamped boundary conditions at one end and an attached mass/inertia at the *** addition,the effect of the transverse vibration of the inextensible arm on its axial behavior is *** the axial rigidity,the effect makes the rigid body dynamics invalid for the axial behavior of the ***,num.rical simulations are conducted to evaluate the performance of the developed model,and the results are compared with those obtained by the finite element *** comparison confirms the validity of the proposed dynamic model for the *** to the mentioned features,this model can be reliable for investigating the system’s vibrational behavior and implementing vibration control algorithms.

关键词： planar moving Timoshenko beam non-rigid non-elastic axial effect as-sumed mode method(Amm) nonlinear motion analysis

Large magnetocaloric effect and magnetic properties of EurhO3

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Journal of rare Earths 2024年第9期42卷 1724-1729页

作者： m.Lassri m.sajieddine A.Elouafi A.El Hachmi s.El Ouahbi r.moubah Laboratory of Energy and materials Engineering (LGEm) University of Sultan Moulay SlimaneFaculty of Science and Technology (FST) Institute of Applied Physics (IAP)-school of Industrial management (EmINEs) Mohammed Ⅵ Polytechnic University National school of Applied sciences (ENsA) University of Sultan Moulay Slimane Laboratory of mechanics Production and Industrial Engineering (LMPGI)Higher School of Technology of Casablanca (ESTC)University of Hassan Ⅱ Casablanca Laboratory of radiation on matter and Instrumentation (LrmI) Faculty of Science and Technology (FST) SettatHassan Ⅰ University Laboatory of Physics of Advanced materials and Thermic (LPmAT) Faculty of Science Ain Chock (FSAC)University of Hassan Ⅱ Casablanca

We report on the structural,magnetic,and magnetocaloric properties of *** oxidation states of Eu and rh ions were studied using X-ray photoelectron spectroscopy（XPs）.It is found that the Eu ions are mainly in the divalent oxidation state while the rh ions have+4 ***3powders are found to be antiferromagnetic with a second order magnetic transition at Neel temperature（TN=2.9 K）.Analysis of the magnetic susceptibility versus temperature data in terms of the curie=Weiss law:(χ=c/（T-θW）) for T>TN,yields θW=-3.1 K and effective magne tic moment ■,which is close to the theoretical value ■.The magnetic entropy change(-Δsm),was determined by em ploying the thermodynam ic maxwell's *** μ0H=5 T and near TN,■ and relative cooling power（rcP） exhibit large values of 33.7 J/（kg·K） and 238 J/kg,*** large magnitude of-Δsmand rcP show that the EurhO3compound could be a potential candidate to be used in cryogenic magnetic refrigeration.

关键词： cryogenic magnetic refrigeration magnetic properties magnetocaloric effect rare earths X-ray photoelectron spectroscopy

Factors influencing farm.rs’adoption of solar water-pumping systems in Gujarat

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clean Energy 2024年第3期8卷 157-165页

作者： m sathish Kum.r Y.A.Lad r.s.Pundir International Agribusiness management Institute Anand Agricultural UniversityAnand388110GujaratIndia Department of HrD&Pm International Agribusiness Management InstituteAnand Agricultural UniversityAnand388110GujaratIndia Department of Agribusiness Economics and Policies International Agribusiness Management InstituteAnand Agricultural UniversityAnand388110GujaratIndia

Agriculture has played an important role in the growth of the Indian *** and electricity are essential inputs for agriculture *** produces the third-largest amount of electricity in the world,behind china and the *** an incentive to increase production,most states provide free electricity to *** electricity has decreased groundwater levels and increased electricity *** objective of this study was to find out the factors that influenced farm.rs to adopt a solar water-pumping system in *** samples were randomly *** study examined the entire state of *** hundred and fifty farm.rs who adopted solar water-pumping systems were interviewed,including 50 banana farm.rs,50 cotton farm.rs and 50 groundnut *** data were collected through an *** adoption of solar water-pumping systems by farm.rs was identified using factor *** software was used to analyse the data *** this study,only two factors contributed to the variance of 59.469%.The adoption of solar water pumps by farm.rs was influenced by government policy and economic *** economic benefit variance of 33.20%was found,while a government policy variance was 26.27%.A solar water-pumping system has low initial costs,flexible credit policies motivate adoption,solar water-pumping systems can save electricity,and maintenance and repair costs are *** policy that includes solar water-pumping systems is motivated by awareness,subsidies for adoption and a fair price to sell energy *** are recommended to adopt a solar water-pumping system in conjunction with a drip irrigation system to receive additional *** successful scheme will be recommended to other states in India for implementation.

关键词： solar water-pumping system factor analysis banana cotton groundnut fam.rs