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Lattice Boltzmann method formulation for simulation of thermal radiation effects on non-Newtonian Al_(2)O_(3) free convection in entropy determination

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Applied mathematics and mechanics(English Edition) 2024年第6期45卷 1085-1106页

作者： m.NEmATI m.SEFID A.KARImIPOUR A.J.CHAmKHA Faculty of mechanical Engineering Yazd UniversityYazd ***Iran Department of mechanical Engineering Najafabad BranchIslamic Azad UniversityNajafabad ***Iran Faculty of Engineering Kuwait College of Science and TechnologyDoha 35004Kuwait

The simultaneous investigation on the parameters affecting the flow of electrically conductive fluids such as volumetric radiation,heat absorption,heat generation,and magnetic field(mF)is very vital due to its existence in various sectors of industry and *** present research focuses on mathematical modeling to simulate the cooling of a hot component through power-law(PL)nanofluid convection *** temperature reduction of the hot component inside a two-dimensional(2D)inclined chamber with two different cold wall shapes is *** formulation of the problem is derived with the lattice Boltzmann method(LBm)by code writing via the FORTRAN *** variables such as the radiation parameter(0–1),the Hartmann number(0–75),the heat absorption/generation coefficient(−5–5),the fluid behavioral index(0.8–1.2),the Rayleigh number(103–105),the imposed mF angle(0°–90°),the chamber inclination angle(−90°–90°),and the cavity cold wall shape(smooth and curved)are *** findings indicate that the presence of radiation increases the mean Nusselt number value for the shear-thickening,Newtonian,and shear thinning fluids by about 6.2%,4%,and 2%,*** most cases,the presence of nanoparticles improves the heat transfer(HT)rate,especially in the cases where thermal conduction dominates *** is the lowest cooling performance index and mF effect for the cavity placed at an angle of 90°.The application in the design of electronic coolers and solar collectors is one of the practical cases of this numerical research.

关键词： thermal performance analysis heat absorption/generation power-law(PL)Al_(2)O_(3)nanofluid magnetohydrodynamics natural convection volumetric radiation inclined cavity

Impact of carbimazole combined with vitamin E on testicular injury induced by experimental hyperthyroidism in adult albino rats:oxidative/inflammatory/apoptotic pathways

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Asian Journal of Andrology 2024年第4期26卷 396-401页

作者： Ramadan S Hussein moustafa m Eyada Rashad m mostafa Samah m Elaidy Shereen H Elsayed Hany m Saad Department of Dermatology College of Medicine Prince Sattam Bin Abdulaziz UniversityAl-Kharj 16242Saudi Arabia Department of Dermatology Andrology and STDsAssiut Police HospitalAssiut 71525Egypt Department of Dermatology Venereology and AndrologyFaculty of MedicineSuez Canal UniversityIsmailia 41522Egypt Department of Andrology and Sexology Faculty of MedicineSuez Canal UniversityIsmailia 41511Egypt Department of Clinical Pharmacology Faculty of MedicineSuez Canal UniversityIsmailia 41511Egypt Department of Rehabilitation Sciences Faculty of Health and Rehabilitation SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh 12271Saudi Arabia.

Thyroid hormones play essential roles in spermatogenesis,but their effects on infertile males remain poorly *** study aimed to evaluate the impact of combining carbimazole(CBZ)with vitamin E(VE)on testicular injury induced by experimental hyperthyroidism in adult albino rats,focusing on oxidative,inflammatory,and apoptotic *** this experimental study,64 adult male albino Wistar rats were divided into eight groups:Group I(control-untreated),Group II(CBZ-control),Group III(VE-control),Group IV(CBZ+VE-control),Group V(levothyroxine-induced testicular injury),Group VI(levothyroxine+CBZ-treated),Group VII(levothyroxine+VE-treated),and Group VIII(levothyroxine+CBZ+VE-treated).The study was conducted in the Faculty of medicine,Suez Canal University(Ismailia,Egypt).After cervical decapitation,both testes and epididymis were examined histopathologically and *** differences were observed among groups concerning malondialdehyde(mDA),glutathione(GSH),superoxide dismutase(SOD),and catalase(CAT;all Pmerase chain reaction analysis showed significant differences in tumor necrosis factor-α(TNF-α),interleukin-10(IL-10),Bcl-2-associated X protein(BAX),B-cell lymphoma 2 protein(Bcl2),p53,Caspase-3,Caspase-8,Caspase-9,and nuclear factor-kappa B(NF-κB)mRNA levels(all Pminiferous tubules and ***,the Group VIII showed improved spermatogenesis and a decrease in testicular side *** addition of VE to the treatment of hyperthyroid rats with CBZ reduced testicular side effects and seminiferous tubular affection when potentially improving *** research is needed to elucidate the underlying mechanisms fully.

关键词： antithyroid drugs testicular injury thyroid gland vitamin E

In Vitro Antioxidant and Radio Protective Activities of Lycopene from Tomato Extract against Radiation—Induced DNA Aberration

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Journal of Biosciences and medicines 2024年第2期12卷 202-213页

作者： Safaiatul Islam abu Hena mostofa Kamal md. Ziaur Rahman Protul Kumar Roy A.Y.K. md. masud Rana molecular Radiobiology and Biodosimetry Division Institute of Food and Radiation Biology Bangladesh Atomic Energy Commission Savar Bangladesh

Background: The accumulation of free radicals is linked to a number of diseases. Free radicals can be scavenged by antioxidants and reduce their harmful effects. It is therefore essential to look for naturally occurring antioxidants that come from plants, as synthetic antioxidants are toxic, carcinogenic and problematic for the environment. Lycopene is one of the carotenoids, a pigment that dissolves in fat and has antioxidant properties. materials and methods: The antioxidant and free radical scavenging activity were assessed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The impact of lycopene on bacteria (E. coli) susceptibility to γ-radiation was examined by radio sensitivity assay. The study also examined the induction of strand breaks in plasmid pUC19 DNA and how lycopene extract protected the DNA from γ-radiation in vitro. Results: At varying concentrations, lycopene demonstrated its ability to scavenge free radicals such as 2, 2-diphenyl-1-picrylhydrazyl (DPPH). IC50 for lycopene was determined at 112 μg/mL which was almost partial to IC50 of standard antioxidant L-ascorbic acid. The D10 value 180 Gy of E. coli was found to be >2-fold higher in the extract-containing lycopene sample than in the extract-free controls. The lycopene extracts inhibited the radiation-induced deterioration of the plasmid pUC19 DNA. At an IC50 concentration, lycopene provided the highest level of protection. Conclusion: Lycopene functions as an efficient free radical scavenger and possible natural antioxidant source. For cancer patients and others who frequently expose themselves to radiation, lycopene may be a useful plant-based pharmaceutical product for treating a variety of diseases caused by free radicals.

关键词： Radio Protective Antioxidants Free Radical DNA Damage pUC19 Plasmid Gamma Irradiation DPPH

CFD-DEm analysis of particle polydispersity on the performance of fluidised bed reactor during silane pyrolysis Author links open overlay panel

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Particuology 2024年第8期91卷 72-87页

作者： Akshayveer Vijay m.Shinde mS2Discovery Interdisciplinary Research Institute Wilfrid Laurier UniversityWaterlooOntarioN2L3C5Canada Department of Chemical Engineering Indian Institute of Technology(BHU)Varanasi221005India

A CFD-DEm model is developed for chemical vapour deposition of silane in a fluidized bed reactor to investigate the effect of polydispersity on local phase dynamics,mass and heat transport,as well as the rate of Si *** gas-phase fines formation and heterogeneous deposition on the seed particle,as well as the scavenging effect for Si particle growth,are *** method is first validated against the experimentally measured Si deposition rate,percentage of fine production and minimum fluidisation ***,the properties,primarily particle intermixing,fluidisation behaviour and bubble dynamics along with the deposition process,are analyzed for several polydisperse beds under various operating *** effect of polydispersity of the bed on a fraction of the bubble size,dense phase expansion and interchange coefficient between various phases is thoroughly investigated to establish a correlation with reactor *** results show that broad-Gaussian particle size distribution(PSD)exhibits excellent improvement in fluidisation behaviour,resulting in a high deposition rate,and minimum formation of Si fines.

关键词： CFD-DEm method Chemical vapour deposition(CVD) Particle size distribution Silicon Gas-solid fluidized bed

Synthesis and Thermal Characterization of Solar Salt-Based Phase Change Composites with Graphene Nanoplatelets

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Journal of Thermal Science 2024年第2期33卷 491-500页

作者： Pethurajan VIGNESHWARAN Saboor SHAIK Sivan SURESH müslüm ARICI Asif AFZAL Department of Thermal and Energy Engineering School of Mechanical Engineering(SMEC)Vellore Institute of TechnologyVelloreTamil NaduIndia Nanotechnology Research Laboratory Department of Mechanical EngineeringNational Institute of TechnologyTiruchirappalliTamil NaduIndia mechanical Engineering Department Engineering FacultyKocaeli UniversityUmuttepe CampusKocaeli41001Turkey Department of mechanical Engineering P.A.College of Engineering(affiliated to Visvesvaraya Technological UniversityBelagavi)Mangaluru574153India

Thermal energy storage(TES) systems use solar energy despite its irregular availability and day-night temperature *** work reports the thermal characterizations of solar salt-based phase change composites in the presence of graphene nanoplatelets(GNP).Solar salt(60:40 of NaNO_(3):KNO_(3)) possessing phase transition temperature and melting enthalpy of 221.01℃ and 134.58 kJ/kg is proposed as a phase change material(PCm) for high-temperature solar-based energy storage *** conductivity must be improved to make them suitable for widespread applications and to close the gap between the system needs where they are *** is added at weight concentrations of 0.1%,0.3%,and 0.5% with solar salt using the ball milling method to boost its thermal *** studies indicated the formation of a uniform surface of GNP on solar *** spectrum peaks identified the physical interaction between salt and *** characterization of the composites,such as thermal conductivity,DSC and TGA was carried out for the samples earlier and later 300 thermal cycles.0.5% of GNP has improved the thermal conductivity of salt by 129.67% and after thermal cycling,the enhancement reduced to 125.21% indicating that thermal cycling has a minor impact on thermal *** change temperature decreased by around 2.32% in the presence of0.5% GNP and the latent heat reduced by 4.34% after thermal *** thermograms depicted the composites initiated the weight loss at around 550℃ after which it was *** thermal cycling,the weight loss initiated at ~40℃ lower compared to pure salt,which was found to be a minor *** characterization of solar salt and GNP-based solar salt composites revealed that the composites can be used for enhanced heat transfer in high-temperature solar-based heat transfer and energy storage applications.

关键词： thermal energy storage high temperature solar salt graphene nanoplatelets thermal characterization

Asperity-based modification on theory of contact mechanics and rubber friction for self-affine fractal surfaces

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Friction 2021年第6期9卷 1707-1725页

作者： Anahita EmAmI Seyedmeysam KHALEGHIAN saied TAHERI Texas State University 601 University DriveSan MarcosTexas 78666USA Virginia Polytechnic Institute and State University 460 Old Turner Street BlacksburgBlacksburgVirginia 24061USA

modeling the real contact area plays a key role in every tribological process,such as friction,adhesion,and *** between two solids does not necessarily occur everywhere within the apparent contact *** the multiscale nature of roughness,Persson proposed a theory of contact mechanics for a soft and smooth solid in contact with a rigid rough *** this theory,he assumed that the vertical displacement on the soft surface could be approximated by the height profile of the substrate *** this assumption gives an accurate pressure distribution at the interface for complete contact,when no gap exists between two surfaces,it results in an overestimation of elastic energy stored in the material for partial contact,which typically occurs in many practical *** issue was later addressed by Persson by including a correction factor obtained from the comparison of the theoretical results with molecular dynamics *** paper proposes a different approach to correct the overestimation of vertical displacement in Persson’s contact theory for rough surfaces with self-affine fractal *** results are compared with the correction factor proposed by *** main advantage of the proposed method is that it uses physical parameters such as the surface roughness characteristics,material properties,sliding velocity,and normal load to correct the *** method is also implemented in the theory of rubber *** results of the corrected friction model are compared with *** results confirm that the modified model predicts the friction coefficient as a function of sliding velocity more accurately than the original model.

关键词： contact area rubber friction self-affine fractals tribology surface roughness

Effect of Fluidic Diode on Performance of Unidirectional Impulse Turbine

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Journal of Thermal Science 2024年第3期33卷 807-814页

作者： DODDAmANI Hithaish ABDUS Samad mANabu Takao SHINYA Okuhara m m ASHRAFUL Alam Department of Ocean Engineering Indian Institute of Technology MadrasChennai600036India Department of mechanical Engineering National Institute of TechnologyMatsue CollegeShimane6908518Japan Center of Support Practical Education National Institute of TechnologyMatsue CollegeShimane6908518Japan Department of Transportation Engineering Osaka Sangyo UniversityDaito5748530Japan

A pair of unidirectional turbines(UT)can operate in oscillatory airflow without additional ***,this arrangement suffers from poor flow rectification.A fluidic diode(FD)offers variable hydrodynamic resistance based on the flow direction,and this can be coupled with UT to improve flow *** this work,a numerical investigation on the effect of FD with UT is presented using the commercial fluid dynamics software ANSYS Fluent 16.1 with k-ωSST turbulence closure *** domains of UT and FD are numerically validated individually with experimental ***,both are coupled to obtain the combined effect,and these results are compared with the analytical *** was observed that coupling FD with UT improved the unit's performance at the lower flow coefficient(mance decreased as the flow coefficient *** to the diode's presence,fluid leaving the turbine experiences higher resistance at a higher flow coefficient,which decreases the overall performance of the combined unit.

关键词： wave energy oscillating water column unidirectional impulse turbine fluidic diode flow rectification

Cooperative Target Fencing of multiple Vehicles for a General Target with Connectivity Preservation and Collision Avoidance

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Journal of Systems Science & Complexity 2024年第1期37卷 136-151页

作者： PAN Zini CHEN Ben m Department of mechanical and Automation Engineering The Chinese University of Hong KongHong KongChina

In this paper,the authors study the cooperative target-fencing problem for n-dimensional systems and a target with a general *** using the velocity of the vehicles,a position feedback control law is proposed to fence the general target into the convex hull formed by the ***,the dynamics of each vehicle is described by a double-integrator *** potential functions are designed to guarantee connectivity preservation of the communication network and collision avoidance among the *** proposed approach can deal with a target whose trajectory is any twice continuously differentiable function of *** effectiveness of the result is verified by a numerical example.

关键词： multi-agent systems networked systems target fencing

Oviposition Site Preference and Its Effects on Subsequent Development of Variegated Grasshopper (Zonocerus variegatus L.) under Laboratory Conditions

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Advances in Entomology 2024年第3期12卷 143-154页

作者： Saffea Joseph Torto abu James Sundufu Alusaine Edward Samura Sahr Ngoba Fomba Dennis Peter musa Skeku Alfred Kanu Prince Emmanuel Norman Department of Crop Protection School of Agriculture and Food Sciences Njala Sierra Leone Department of Horticulture School of Natural Resources Management Njala University Njala Sierra Leone Department of Crop Science School of Agriculture and Food Sciences Njala University Njala Sierra Leone Germplasm Enhancement and Seeds Systems Sierra Leone Agricultural Research Institute Freetown Sierra Leone

Female grasshoppers can affect the fitness of their offspring through their selection of oviposition site. Knowledge of soil type on oviposition, and its effects on subsequent development can provide guidelines for habitat manipulations that reduce the harmful effects of these pests on farmers fields. The influence of soil types on the oviposition site preference of variegated grasshopper (Zonocerus variegatus L.) reared some cassava (manihot esculenta Crantz) varieties, was investigated in a cage trial carried out at the Bio factory laboratory, School of Agriculture and Food Sciences, Njala University, Sierra Leone during 2022/2023. The treatments comprised three soil types (Sandy, Loamy and Clay), each with three replications laid out in a randomized complete block design (RCBD) in wooden cages. Data were collected on the following development parameters including, Net reproductive growth ratio (R0), Generation time (Tc), Intrinsic rate of increase (rm), Finite rate of increase (), Doubling time (Dt), and overall survivorship. Findings revealed that, Z. variegatus L. preferred sandy soil in which, on average, most eggs were deposited (338, 6.62 4.40), followed by loamy soil, 286 (5.53 3.96), and then, clayey soil, 200 (3.91 3.85);though, the differences were not significant. This study established that Z. variegatus deposited more eggs in sandy soil > loamy soil > clayey soil, respectively;and subsequent survivorship of the immature unto mature adult insect, revealed a similar order. This indicates that the sandy soil is the most preferred substrate for oviposition and subsequent development into adult insects.

关键词： Development Oviposition Oviposition Site Preference Soil Types Variegated Grasshopper