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reciprocity relation between Alternative Gravity Formulas

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Journal of Applied Mathematics and Physics 2024年第4期12卷 1432-1440页

作者： Hans Hermann otto Department of Materials Science and Crystallography Clausthal University of Technology Clausthal-Zellerfeld Germany

We compare Newton’s force law of universal gravitation with a corrected simple approach based on Bhandari’s recently presented work, where the gravitation constant G is maintained. A reciprocity relation exists between both alternative gravity formulas with respect to the distances between mass centers. We conclude a one-to-one mapping of the two gravitational formulas. We don’t need Einstein’s construct of spacetime bending by matter.

关键词： Gravity Formulas reciprocity Distance relation Newton Einstein Bhandari Higgs Field Dirac’s Large Number

Analysis and Optimization of Operational and Pollutant Attributes of Diesel Engine with CNT-Infused Orange Peel Biodiesel-Diesel Blend Fuel

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Journal of Thermal Science 2024年第2期33卷 761-778页

作者： ranjeet rAI r.r.SAHOO Mechanical Engineering Department GLA UniversityMathura281406India Mechanical Engineering Department IIT(BHU)Varanasi221005India

The current study is performed to find sustainable solutions for the future of transportation and environmental *** conventional methods and experimental design table(L16 Orthogonal Array)techniques have been employed to examine and optimize a diesel-powered engine's operational and pollutant *** L16 Orthogonal Array is obtained through Taguchi's experimental design approach using Minitab 16 *** experimental design incorporated three control variables,namely engine speed,fuel type,and engine load,each with four *** operational parameters,namely brake thermal efficiency(BTE)and brake specific fuel consumption(BSFC),as well as the emission characteristics,including hydrocarbon(HC),carbon monoxide(CO),nitrogen oxide(NO),and smoke emissions,were acquired using the L16 orthogonal array(OA) and subsequently *** utilization of methodologies such as signal-to-noise(S/N) ratio and grey analysis was employed to determine the optimal operational state of the engine to achieve maximum performance while minimizing *** engine's ideal state of operation,in terms of BTE and BSFC,was determined to be at 75% engine load,1000 r/min engine speed,and using 10^(-4)(in vol) carbon nanotube incorporated 20% orange peel biodiesel(OPB20CNT100) blended fuel(A3-B1-C4).The study indicated that engine load significantly influenced BTE and BSFC,with 84.05% and 87.79% contribution factors,*** 25% engine load,1000 r/min,and OPB20CNT100 fuel(A1-B1-C4) CO,smoke,NO,and HC emissions were the *** load affects emissions the *** BSFC increased 3.10% and NO emissions 1.77%.BTE,CO,smoke,and HC emissions decreased by 1.9%,12.29%,47.05%,and 47.22%,respectively,at optimal operating conditions concerning diesel *** study shows that Taguchi-Grey's experimental design optimizes diesel engine operational and pollutant *** outcomes revealed that orange peel biodiesel infused with CNT can replace diesel fuel in a

关键词： Taguchi-Grey method OPB20CNT100 transesterification S/N ratio GrG HC CO and NO

Descriptive and Comparative Histology of the Urinary System of the Hematophagous Bats Desmodus rotundus and Diphylla ecaudata

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Open Journal of Veterinary Medicine 2024年第7期14卷 180-191页

作者： María Guadalupe ramírez-Muñoz Samantha Jardon-Xicotencatl José Ignacio Olave-leyva Armando Zepeda-Bastida Juan Ocampo-López Histology and Histopathology Laboratory Academic Area Veterinary Medicine and Zootechnics Academic Area Veterinary Biotechnology Institute of Agricultural Sciences Autonomous University of the Hidalgo State (UAEH) Tulancingo Mexico Multidisciplinary research Unit L4 (Veterinary Morphology and Cell Biology) UNAM-FESC Campus 4 Cuautitln Izcalli Mexico Academic Area Veterinary Medicine and Zootechnics Institute of Agricultural Sciences Autonomous University of the Hidalgo State (UAEH) Tulancingo Mexico Cellular and Molecular Biology Laboratory Academic Area Veterinary Medicine and Zootechnics Institute of Agricultural Sciences Autonomous University of the Hidalgo State (UAEH) Tulancingo Mexico

Desmodus rotundus and Diphylla ecaudata, both of which are mammals of the order Chiroptera, Desmodontidae family, their diet consisting exclusively of blood. D. rotundus is the main vector and transmitter of the rabies virus, which affects human beings as well as several livestock species so the study of this bat species is of high importance within the fields of animal agriculture and public health. The present study describes and compares the histologic characteristics of the urinary system of two hematophagous bat species. A total of 5 bats from each species were captured in the municipalities of Progreso de Obregón, Hidalgo (D. rotundus), and Huayacocotla, Veracruz (D. ecaudata). Organs belonging to the urinary system were extracted: kidneys, ureters, urinary bladder, and urethra;samples were fixed using 10% formalin and processed by the paraffin embedding technique, obtaining sections of 5 µm thickness, which in turn were stained using hematoxylin-eosin (H-E) and Gomori trichrome (GT) stains. From the obtained histologic preparations, a descriptive and comparative analysis of the structural organography of the urinary system of both species was made, and no noteworthy histological differences between samples were noted. The present research is intended to provide a framework for future studies of these species’ currently understudied microscopic anatomy.

关键词： Microscopic Anatomy Vampire Bats Kidneys Comparative Morphology

Multidimensional images and aberrations in STEM

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Chinese Physics B 2024年第9期33卷 68-74页

作者： Eric r.Hoglund Andrew r.Lupini Center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTN 37831United States

recent advances in scanning transmission electron microscopy(STEM)have led to increased development of multidimensional STEM imaging modalities and novel image reconstruction *** interest arises because the main electron lens in a modern transmission electron microscope usually has a diffraction-space information limit that is significantly better than the real-space resolution of the same *** state-of-affairs is sometimes shared by other scattering methods in modern physics and contributes to a broader excitement surrounding multidimensional techniques that scan a probe while recording diffraction-space images,such as ptychography and scanning nano-beam ***,the contrasting resolution in the two spaces raises the question as to what is limiting their effective ***,we examine this paradox by considering the effects of aberrations in both image and diffraction planes,and likewise separate the contributions of pre-and post-sample *** consideration provides insight into aberration-measurement techniques and might also indicate improvements for super-resolution techniques.

关键词： scanning transmission electron microscopy (STEM) aberrations

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 numerous *** 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 more 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

Holographic dark energy in non-conserved gravity theory

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Communications in Theoretical Physics 2024年第4期76卷 126-133页

作者： H r Fazlollahi Institute of Gravitation and Cosmology Peoples Friendship University of Russia(RUDN University)6 Miklukho-Maklaya StMoscow117198Russia

recently, reconsidering the rastall idea T_(μ;νν)^(v)=α_(,μ) through relativistic thermodynamics gives a new form for the scalar field α which led us to construct modern modified theory of gravity debugged ‘non-conserved gravity theory’ Fazlollahi 2023 Euro. Phys. J. C 83 923. This theory unlike other modified theories of gravity cannot directly explain the current acceleration expansion in the absence of the cosmological constant and or existence of other forms of dark energy. Hence, in this study we have reinvestigated holographic dark energy Ρ_(X)~H^(2) in the non-conserved theory of gravity. In this context, the density and pressure of dark energy depend on the non-conserved term and density of the dust matter field. As shown, due to non-conservation effects on large-scale structures, unlike the original holographic model, our model onsets an acceleration epoch for the current Universe satisfies observations. Moreover, the interaction and viscous scenarios are studied for this model.

关键词： non-conserved gravity covariant form of thermodynamics holographic dark energy

Investigating the impact of the universal function of the nuclear proximity potential in heavy-ion fusion cross sections

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Communications in Theoretical Physics 2024年第5期76卷 86-93页

作者： r Gharaei E Sarvari Department of Physics Sciences FacultyHakim Sabzevari UniversityPO Box 397SabzevarIran Department of Physics Faculty of ScienceFerdowsi University of MashhadPO Box 91775-1436MashhadIran Science Faculty Department of PhysicsTarbiat Modares UniversityTehranIran

The fusion barriers and cross sections of 15 colliding systems with 320≤Z_(1)Z_(2)≤1512 are investigated in detail to understand the influence of the universal function of proximity potential formalism in the heavy-ion fusion *** realize this goal,we select three versions of the phenomenological proximity potentials,including Prox.77,Zhang 2013,and Guo 2013,to calculate the nucleus-nucleus *** experimental fusion cross sections for the selected reactions are analyzed using the standard coupled-channel calculations,including couplings to the low-lying 2^(+)and 3^(-)states in the target and *** calculated results show that the universal functions of the Guo 2013 and Prox.77 models provide the lowest and highest fusion barriers,*** addition,it is found that the height of the fusion barriers is enhanced by increasing the mass number of the projectile from light to heavy *** highest sensitivity to the mass number of the projectile belongs to the results of Prox.77.A discussion is also presented on the influence of the universal function on the radial behavior of the interaction potential in the allowed region for overlapping *** results reveal that the best fit to the experimental data of the fusion cross sections for the reactions involving light and medium nuclei is obtained using the universal function of the Zhang 2013 *** the heavier systems,the results of the Guo 2013 model at sub-barrier energies provide a good description of the available data.

关键词： fusion reactions proximity-type potentials universal function coupled-channel calculations

Pile foundation in alternate layered liquefiable and non-liquefiable soil deposits subjected to earthquake loading

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 359-376页

作者： Praveen Huded M Suresh r Dash LEA Associates South East Asia Pvt.Ltd. New Delhi 110044India Indian Institute of Technology Bhubaneswar Khurda 752050India

Pile foundations are still the preferred foundation system for high-rise structures in earthquake-prone *** foundations have experienced failures in past earthquakes due to *** on pile foundations in liquefiable soils has primarily focused on the pile foundation behavior in two or three-layered soil ***,in natural occurrence,it may occur in alternative layers of liquefiable and non-liquefiable ***,the experimental and/or numerical studies on the layered effect on pile foundations have not been widely addressed in the *** of the design codes across the world do not explicitly mention the effect of sandwiched non-liquefiable soil layers on the pile *** the present study,the behavior of an end-bearing pile in layered liquefiable and non-liquefiable soil deposit is studied *** study found that the kinematic bending moment is higher and governs the design when the effect of the sandwiched non-liquefied layer is considered in the analysis as opposed to when its effect is ***,ignoring the effect of the sandwiched non-liquefied layer in a liquefiable soil deposit might be a nonconservative design approach.

关键词： pile foundation liquefaction alternately layered soil fixity effect layered effect

Effect of cylinder wall parameters on the final packing density of mono-disperse spheres subject to three-dimensional vibrations Author links open overlay panel

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Particuology 2024年第8期91卷 211-225页

作者： Jack r.Grogan Andrei L.Nicuşan Christopher r.K.Windows-Yule School of Chemical Engineering The University of BirminghamEdgbastonBirminghamB152TTUK

Achieving densely packed particles is desirable within the industries of ceramics,pharmaceuticals,defence and additive *** this work,we use the discrete element method(DEM)to determine the effect of wall parameters on the final packing density of mono-disperse spheres subject to 4 varying three-dimensional vibration and fill *** focus specifically on the impact of the container wall parameters on the particles'final packing *** on from the validation of the DEM simulation the particle-wall coefficient of restitution,the particle-wall coefficient of rolling friction and the particle-wall coefficient of sliding friction were varied individually and the effect on the final packing density *** relatively low particle-particle friction glass beads,the effect of these wall properties had no discernible effect on the final packing density *** on from these findings the particle-wall properties were varied at the extreme values of particle-particle coefficient of rolling friction and particle-particle coefficient of sliding *** a particle-particle coefficient of sliding friction=1,increases in particle-wall coefficient of restitution resulted in a minor increase in the final packing density of particles though this was not statistically *** a particle-particle coefficient of sliding friction=1,increases in particle-wall coefficient of rolling friction resulted in a minor decrease in the final packing density of the particles though again not to a degree where the trend can,with complete certainty,be distinguished from the random error across the ***,when the particle-particle coefficient of sliding friction=1,increases in particle-wall coefficient of sliding friction resulted in a significant decrease in the final packing density of *** decrease was attributed to the propagation of force chains throughout the *** significant decrease in final packing density with

关键词： Vibropacking Packing Densification Vibration Discrete element method Friction Wall friction restitution