检索结果-南通市图书馆

Microstructure,mechanical properties and corrosion behavior of Al-Si-Cu-Zn-X(X=Bi,Sb,Sr) die cast alloy

在线全文

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2016年第1期26卷 28-38页

作者： Saeed FArAhANY Ali OUrDJ1NI hamid reza bakhsheshi-rad Department of Materials and Mechanical Engineering Buein Zahra Technical UniversityQazvin 345 1745346Iran Department of Mechanical Engineering Faculty of EngineeringUniversity of OttawaOttawa161 Louis PasteurKIN 6N5Canada Department of Materials Manufacturing and Industrial EngineeringFaculty of Mechanical EngineeringUniversiti Teknologi Malaysia(UTM)Johor Bahru 81310Malaysia

The microstructure evolution, mechanical and corrosion properties of Al-11Si-2Cu-0.8Zn die cast alloy treated with Bi, Sb and Sr additions were investigated. The results of mechanical testing showed that all additions increased impact toughness, ultimate tensile strength, and elongation of the alloy as a result of change in eutectic Si morphology. The analysis of fracture surfaces revealed that with addition of Sr and to lesser extent Bi and Sb, the alloy exhibited a predominantly ductile fracture rather than quasi-cleavage brittle fracture. Moreover, with the additions of Sr, Bi and Sb, the quality index increased to 164.7 MPa, 156.3 MPa and 152.6 MPa respectively from 102 MPa for the base alloy. Polarization corrosion tests conducted in sodium chloride solution showed that the corrosion potential shifted to more negative values with additions of Sb, Bi and Sr, respectively. Corrosion immersion tests also revealed that the element additions have a detrimental effect on the corrosion rate of alloys, due to the increase of boundaries between the Al and eutectic Si phases.

关键词： aluminium die cast alloy melt treatment mechanical properties fracture corrosion

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

在线全文

学校读者我要写书评

暂无评论

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

在线全文

学校读者我要写书评

暂无评论

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

Lower limb balance,ankle dorsiflexion,orofacial tissue pressure,and occlusal force of rugby players

在线全文

学校读者我要写书评

暂无评论

Sports Medicine and health Science 2024年第2期6卷 173-178页

作者： rafael r.Machado Marcelo Palinkas Paulo B.de Vasconcelos Sara Gollino Veridiana W.Arnoni Marcos Vinicios r.Prandi Isabela h.regalo Selma Siessere Simone C.h.regalo School of Dentistry of ribeirao Preto University of Sao PauloBrazil National Institute for Translational Medicine(INCT-TM) Ribeirao PretoBrazil

This cross-sectional study examined the lower limb balance,ankle dorsiflexion,orofacial tissue pressure,and occlusal strength of rugby ***-six participants were divided into groups:rugby players(n=13)and healthy sedentary adults(n=13).Participants underwent an analysis of lower limb balance using a composite score(Y-Balance Test).Ankle dorsiflexion was measured using the Lunge *** Iowa Oral Performance Instrument was employed to measure orofacial tissue *** force was measured with a dynamometer,and T-Scan assessed occlusal contact *** were analyzed using the t-test(ph age and weight as covariates,where it is possible to verify that these factors did not influence the results *** differences were observed in the balance of the right(p=0.07)and left(p=0.02)lower limbs,where rugby players had lower composite *** were significant differences in the right(p=0.005)and left(p=0.004)lunges,with rugby players showing lower values,as well as lower tongue pressure(p=0.01)and higher lip pressure(p=0.03),with significant differences to sedentary *** was no significant difference in molar bite force and distribution occlusal contacts between *** seems to reduce lower limb displacement,cause ankle hypomobility,lead to changes in orofacial tissues,particularly the tongue and *** study is significant for identifying significant differences between rugby players and sedentary individuals,providing new insights into the impact of rugby on health and performance,which can benefit sports training and injury prevention.

关键词： rugby Y-balance test Lunge test Orofacial tissues Occlusal force

Kinematic analysis of flexible bipedal robotic systems

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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

在线全文

学校读者我要写书评

暂无评论

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

在线全文

学校读者我要写书评

暂无评论

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

The quasi-Gramian solution of a non-commutative extension of the higher-order nonlinear Schr?dinger equation

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2024年第3期76卷 51-61页

作者： h W A riaz J Lin Department of Physics Zhejiang Normal UniversityJinhua 321004China

The nonlinear Schr?dinger(NLS)equation,which incorporates higher-order dispersive terms,is widely employed in the theoretical analysis of various physical *** this study,we explore the non-commutative extension of the higher-order NLS *** treat real or complex-valued functions,such as g_(1)=g_(1)(x,t)and g_(2)=g_(2)(x,t)as non-commutative,and employ the Lax pair associated with the evolution equation,as in the commutation *** derive the quasi-Gramian solution of the system by employing a binary Darboux *** soliton solutions are presented explicitly within the framework of *** visually understand the dynamics and solutions in the given example,we also provide simulations illustrating the associated ***,the solution can be used to study the stability of plane waves and to understand the generation of periodic patterns within the context of modulational instability.

关键词： integrable systems Darboux transformation solitons

Observability Analysis of Integrated Electricity and heating Systems with Thermal Quasi-dynamics in Pipelines

在线全文

学校读者我要写书评

暂无评论

CSEE Journal of Power and Energy Systems 2024年第3期10卷 1145-1158页

作者： Zhigang Li Wenjian Zheng Junbo Zhao J.h.Zheng Q.h.Wu School of Electric Power Engineering South China University of TechnologyGuangzhou 510641China Fuzhou Changle District Power Supply Company of State Grid Fujian Electric Power Co. Ltd.Fuzhou 350000China Department of Electrical and Computer Engineering University of ConnecticutStorrsCT 06269USA CSEE IEEE

Observability analysis(OA)is vital to obtaining the available input measurements of state estimation(SE)in an integrated electricity and heating system(IEhS).Considering the thermal quasi-dynamics in pipelines,the measurement equations in heating systems are dependent on the estimated results,leading to an interdependency between OA and *** OA methods require measurement equations be known exactly before SE is performed,and they are not applicable to *** bridge this gap,a scenario-based OA scheme for IEhSs is devised that yields reliable analysis results for a predefined set of time-delay scenarios to cope with this *** its core procedure,the observable state identification and observability restoration are formulated in terms of integer linear *** tests are conducted to demonstrate the validity and superiority of the proposed formulation.

关键词： Integrated electricity and heating system measurement observability analysis state estimation thermal quasi-dynamics