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Particuology 2024年第1期84卷 249-260页

作者： hassan M.hmood Saba A.Gheni Safaa M.r.Ahmed Mudheher M.Ali hamid Yonis Saleh Mohammed h.Mohammed Awad E.Mohammed Marwan A.Mahomood hiba r.Mohammed Ahmed A.hassan Adam harvey North refineries Company Ministry of OilIraq Chemical Engineering Department Tikrit UniversityIraq Ministry of Oil Iraq AL-hawija Technical Institute Northern Technical UniversityMoselIraq School of Engineering Newcastle UniversityUK

To meet the rapidly increasing demand for energy and the dramatic depletion of conventional crude oil,it is imperative to utilize sour *** no coke being produced,oxidative desulfurization(ODS)of naphtha lowers its sulfur content and average molecular *** this article,we outline a method for heavy naphtha non-extractive ODS using a very stable *** technique involves the use of a solid catalyst with oxygen gas as the *** necessitated relatively high mixing intensities;hence a three-phase Oscillatory Baffled reactor(OBr)was *** catalyst was based on the zeolite ZSM-5,prepared from natural kaolin by a series of delamination and activation steps and impregnated with Fe.A TiO2 nanolayer was applied,using the sol-gel method,to prevent rapid *** reactor performance was evaluated to minimize the sulfur content in the naphtha *** to the protective coating,the sulfur conversion stabilized at 90%.The results of this work establish the use of natural clay-based catalysts in a continuous,three-phase ODS,particularly with regard to proving long-term *** also showed that modest ODS can be achieved using an environmentally friendly oxidant,at mild operating conditions,whilst maintaining stability.

关键词： Natural kaoline Desulfurization Three-phase Oscillatory baffled reactor

Convexification of hybrid AC-DC Optimal Power Flow with Line-Commutated Converters

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 617-628页

作者： hongyuan Liang Zhigang Li J.h.Zheng Q.h.Wu School of Electric Power Engineering South China University of TechnologyGuangzhou 510641China

Line-commutated converter (LCC)-based high-voltage DC (hVDC) systems have been integrated with bulk AC power grids for interregional transmission of renewable power. The nonlinear LCC model brings additional nonconvexity to optimal power flow (OPF) of hybrid AC-DC power grids. A convexification method for the LCC station model could address such nonconvexity but has rarely been discussed. We devise an equivalent reformulation for classical LCC station models that facilitates second-order cone convex relaxation for the OPF of LCC-based AC-DC power grids. We also propose sufficient conditions for exactness of convex relaxation with its proof. Equivalence of the proposed LCC station models and properties, exactness, and effectiveness of convex relaxation are verified using four numerical simulations. Simulation results demonstrate a globally optimal solution of the original OPF can be efficiently obtained from relaxed model.

关键词： AC-DC power system convex relaxation linecommutated converter optimal power flow second-order cone programming

Shell-model representations of the microscopic version of the Bohr–Mottelson collective model

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Communications in Theoretical Physics 2024年第8期76卷 81-92页

作者： h G Ganev Joint Institute for Nuclear research Dubna Russia Institute of Mechanics Bulgarian Academy of Sciences

The structure of the irreducible collective spaces of the group Sp（12, r）, which many-particle nuclear states are classified according to the chain Sp（12, r） ? U（6） ? SO（6） ? SUpn（3） ■SO（2） ? SO（3） of the proton–neutron symplectic model（PNSM）, is considered in detail. This chain of the PNSM was recently shown to correspond to a microscopic shell-model version of the Bohr–Mottelson collective model. The construction of the relevant shell-model representations of the Sp（12, r） group along this chain is considered for three nuclei with varying collective properties and from different mass regions. It is shown that the SUpn（3） basis states of the Sp（12, r） representations belonging to the SO（6） irreps with seniority υ ≥ υ0, with υ0denoting the maximal seniority SO（6） irrep contained in the Sp（12, r） bandhead, are always Pauli allowed, but organized in a different way into different SO（6） shells. This is in contrast to the case of filling the levels of the standard three-dimensional harmonic oscillator and using the plethysm operation. Although the SUpn（3） multiplets within υ re not all Pauli forbidden, it is safe to discard them. The results obtained in the present work are important for the practical application of the microscopic version of the Bohr–Mottelson collective model.

关键词： microscopic shell-model version of the Bohr-Mottelson model proton-neutron symplectic model shell-model representations Sp(12, r) dynamical algebra

On an isotropic porous solid cylinder:the analytical solution and sensitivity analysis of the pressure

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Applied Mathematics and Mechanics(English Edition) 2024年第9期45卷 1499-1522页

作者： h.ASGhArI L.MILLEr r.PENTA J.MErODIO Departamento de Matemática Aplicada a las TIC ETS de Ingeniería de Sistemas Informáticos Universidad Politecnica de Madrid School of Mathematics and Statistics University of Glasgow

Within this work, we perform a sensitivity analysis to determine the influence of the material input parameters on the pressure in an isotropic porous solid *** provide a step-by-step guide to obtain the analytical solution for a porous isotropic elastic cylinder in terms of the pressure, stresses, and elastic displacement. We obtain the solution by performing a Laplace transform on the governing equations, which are those of Biot's poroelasticity in cylindrical polar coordinates. We enforce radial boundary conditions and obtain the solution in the Laplace transformed domain before reverting back to the time domain. The sensitivity analysis is then carried out, considering only the derived pressure solution. This analysis finds that the time t, Biot's modulus M, and Poisson's ratio ν have the highest influence on the pressure whereas the initial value of pressure P0plays a very little role.

关键词： 35Q62 74A99 76S05 Biot’s modulus cylinder cylindrical polar coordinate Laplace transform O343 sensitivity analysis

Marinoan glaciation in the Indian subcontinent——Anatomy and global implications

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Journal of Palaeogeography 2024年第2期13卷 293-308页

作者： h.N.Bhattacharya Department of Earth Sciences Techno India UniversityWest BengalSector VSalt LakeKolkata700091India

Detailed sedimentological analysis of the Pokaran Boulder Bed,representing the most basal unit of the Neoproterozoic-Lower Cambrian Marwar Supergroup,clearly indicates its glacial *** glacial sediments are interpreted as an ice-contact submarine fan *** on the detrital and inherited zircon population of the Marwar Supergroup sediments and interlayered pyroclastic deposits,a Marinoan cryochron of the Cryogenian Period is envisaged for the Pokaran Boulder *** well-preserved Ediacaran elements in the post-glacial sedimentary succession also support a Cryogenian to Early Cambrian age of the Marwar *** glacial deposition at the base of the Marwar Supergroup strengthens the regional correlation between the studied sediments with the Lesser himalayan Blaini-Krol-Tal sediments and the haqf Supergroup of *** available zircon ages and paleomagnetic data of the Malani Igneous suite,along with the Marinoan glacial deposits,detrital zircon ages,and Ediacaran fossil elements of the Marwar Supergroup add significant information to the Neoproterozoic Earth history.

关键词： Neoproterozoic Marinoan glaciation Diamictites Pokaran Boulder Bed Marwar Supergroup

Skeletal muscle as a molecular and cellular biomarker of disease progression in amyotrophic lateral sclerosis:a narrative review

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Neural regeneration research 2024年第4期19卷 747-753页

作者： Peter h.King Department of Neurology and Center for Neurodegeneration and Experimental Therapeutics The University of Alabama at BirminghamBirminghamALUSA Birmingham Veterans Affairs Medical Center BirminghamALUSA

Amyotrophic lateral sclerosis is a fatal multisystemic neurodegenerative disease with motor neurons being a primary *** progressive weakness is a hallmark feature of amyotrophic lateral sclerosis,there is considerable heterogeneity,including clinical presentation,progression,and the underlying triggers for disease *** on longitudinal studies with families harboring amyotrophic lateral sclerosis-associated gene mutations,it has become apparent that overt disease is preceded by a prodromal phase,possibly in years,where compensatory mechanisms delay symptom *** 85-90%of amyotrophic lateral sclerosis is sporadic,there is a strong need for identifying biomarkers that can detect this prodromal phase as motor neurons have limited capacity for *** Food and Drug Administration-approved therapies work by slowing the degenerative process and are most effective early in the *** muscle,including the neuromuscular junction,manifests abnormalities at the earliest stages of the disease,before motor neuron loss,making it a promising source for identifying biomarkers of the prodromal *** accessibility of muscle through biopsy provides a lens into the distal motor system at earlier stages and in real *** advent of“omics”technology has led to the identification of numerous dysregulated molecules in amyotrophic lateral sclerosis muscle,ranging from coding and non-coding rNAs to proteins and *** technology has opened the door for identifying biomarkers of disease activity and providing insight into disease mechanisms.A major challenge is correlating the myriad of dysregulated molecules with clinical or histological progression and understanding their relevance to presymptomatic phases of *** are two major goals of this *** first is to summarize some of the biomarkers identified in human amyotrophic lateral sclerosis muscle that have a clinicopathological correlation with disease activi

关键词： amyotrophic lateral sclerosis biomarkers clinicopathological correlation disease progression muscle biomarkers neurogenic atrophy neuromuscular junction non-coding rNAs presymptomatic stages skeletal muscle SOD1G93A mouse model

Dysprosium oxide,alumina,and graphene oxide reinforced polycaprolactone thin films:Thermal stability,morphology,and cell viability

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Journal of rare Earths 2024年第7期42卷 1337-1343,I0005页

作者： Mohamed Tharwat Elabbasy Mohamed r.Atteya Mai A.Samak Mousa Abdelrahman Tahani AlMahmoud M.A.El-Morsy A.A.Menazea M.F.h.Abd El-Kader Department of Public health College of Public Health and Health InformaticsUniversity of Ha'ilHa'il2440Saudi Arabia Food Control Department Faculty of Veterinary MedicineZagazig UniversityZagazig44519Egypt Department of Physical Therapy College of Applied Medical SciencesUniversity of Ha'ilHa'ilSaudi Arabia Department of histology and Cell Biology Faculty of MedicineZagazig UniversityZagazig44519Egypt College of Nursing University of Ha'ilHa'ilSaudi Arabia College of Science and humanities in Al-Kharj Physics DepartmentPlasma Technology and Material Science UnitPrince Sattam Bin Abdulaziz UniversityAl-kharj11942Saudi Arabia Physics Department Faculty of ScienceUniversity of DamiettaNew Damietta34517Egypt Spectroscopy Department Physics Research InstituteNational Research CentreDokki12622GizaEgypt Biophysics Department Faculty of ScienceCairo UniversityGizaEgypt

Developing a biomaterial for wound healing applications is still a ***,dysprosium oxide(Dy_(2)O_(3)),aluminum oxide(Al_(2)O_(3)),and graphene oxide(GO)were embedded in cast films based on polycaprolactone(PCL)to be examined for wound dressing *** techniques were used to characterize the fabricated films including X-ray diffraction(XrD),Fourier transform infrared spectroscopy(FTIr),raman,and scanning electron microscopy(SEM),besides their biological *** thermogravimetric analysis(TGA)exhibits high thermal stability as the scaffold weight decreases slightly to 98.6%after raising the temperature from room temperature to 280℃.The cell viability was investigated and it is shown that the viable cells grow up to approximately 93%at 75μg/***,the cell attachment shows excellent behavior as the cells attach on most of the surface of the modified PCL which shows high biocompatibility.

关键词： Wound healing Polycaprolactone Dy_(2)O_(3) Al_(2)O_(3) Biocompatible rare earths

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

Experimental and numerical investigation on alternatives to sandy gravel

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Defence Technology（防务技术） 2024年第1期31卷 130-141页

作者： V.Denefeld h.Aurich Fraunhofer Institute for high-Speed Dynamics Ernst-Mach-Institut(EMI)Ernst-Zermelo-Str.479104FreiburgGermany Fraunhofer Institute for high-Speed Dynamics Ernst-Mach-Institut(EMI)Am Christianswuhr 279400KandernGermany

The NATO agreement STANAG 4569 defines the protection levels for the occupants of logistic and light armored *** Allied Engineering Publication,AEP-55,Volume 2 document outlines the test conditions for underbelly improvised explosive device(IEDs),which must be buried in water-saturated sandy *** use of sandy gravel has some drawbacks,for instance reproducibility,time consumption,and *** paper focuses on the investigation of four alternatives to sandy gravel,which could produce similar specific and cumulative impulses:a concrete pot filled with water,a concrete pot filled with quartz sand,a steel pot without filling and a concrete pot filled with glass spheres(diameter 200μm—300μm)and different water *** impulses are measured with a ring technology developed at the Fraunhofer EMI.A numerical soil model based on the work of Marrs,2014 and Fi serov a,2006 and considering the soil moisture was used to simulate the experiments with glass spheres at different water contents,showing much better agreement with the experiments than the classical Laine&Sandvik model,even for high saturation *** results can be used to create new test conditions at original scale that are more cost-effective,more reproducible and simpler to manage in comparison to the current tests carried out with STANAG sandy gravel.

关键词： Improvised explosive device(IED) Specific impulse Momentum transfer Sandy gravel Glass spheres Numerical model Soil moisture

Improving the utility of locally differentially private protocols for longitudinal and multidimensional frequency estimates

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Digital Communications and Networks 2024年第2期10卷 369-379页

作者： héber h.Arcolezi Jean-François Couchot Bechara Al Bouna Xiaokui Xiao Inria andÉcole Polytechnique(IPP) PalaiseauFrance Femto-ST Institute Univ.Bourg.Franche-ComtéUBFCCNRSBelfortFrance TICKET Lab. Antonine University Hadat-BaabdaBaabdaLebanon School of Computing National University of SingaporeSingaporeSingapore

This paper investigates the problem of collecting multidimensional data throughout time(i.e.,longitudinal studies)for the fundamental task of frequency estimation under Local Differential Privacy(LDP)*** to frequency estimation of a single attribute,the multidimensional aspect demands particular attention to the privacy ***,when collecting user statistics longitudinally,privacy progressively ***,the“multiple”settings in combination(i.e.,many attributes and several collections throughout time)impose several challenges,for which this paper proposes the first solution for frequency estimates under *** tackle these issues,we extend the analysis of three state-of-the-art LDP protocols(Generalized randomized response–Grr,Optimized Unary Encoding–OUE,and Symmetric Unary Encoding–SUE)for both longitudinal and multidimensional data *** the known literature uses OUE and SUE for two rounds of sanitization(***),i.e.,L-OUE and L-SUE,respectively,we analytically and experimentally show that starting with OUE and then with SUE provides higher data utility(i.e.,L-OSUE).Also,for attributes with small domain sizes,we propose Longitudinal Grr(L-Grr),which provides higher utility than the other protocols based on unary ***,we also propose a new solution named Adaptive LDP for LOngitudinal and Multidimensional FrEquency Estimates(ALLOMFrEE),which randomly samples a single attribute to be sent with the whole privacy budget and adaptively selects the optimal protocol,i.e.,either L-Grr or *** shown in the results,ALLOMFrEE consistently and considerably outperforms the state-of-the-art L-SUE and L-OUE protocols in the quality of the frequency estimates.

关键词： Local differential privacy Discrete distribution estimation Frequency estimation Multidimensional data Longitudinal studies