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Effect of electrical discharge in water on concentration of nitrate solution

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Chinese Physics B 2017年第2期26卷 305-312页

作者： f Sohbatzadeh H Bagheri r Safari Department of Atomic and Molecular Physics Faculty of Basic Sciences University of Mazandaran Babolsar lra

In this work, the effect of electrical discharge on nitrate concentration is considered in aqueous solution. The atmospheric pressure plasma was produced by a high-voltage power supply at 27 k Hz using pin-to-pin configuration. Air, argon,and argon/methane mixture were used to study the working gas effect. UV-VIS spectroscopy and ion chromatography were used to analyze the effect of the electrical discharge on nitrate concentration in deionized water. Optical emission spectroscopy（OES） was applied to diagnose active species inside and on the surface of the deionized water solution. The results of the present work showed that the atmospheric pressure electric discharge with air increases nitrate concentration while it remains constant using argon and argon/methane electrical discharges. It was also revealed that in the presence of air, the electrical discharge reduces p H, acidifying the solution and increasing solution conductivity due to production of extra nitrate ions. On the other hand, argon electrical discharge increases p H and conductivity due to production of OHion in water.

关键词： electric discharge nitrate solution optical spectroscopy

On three-dimensional stress analysis of periodic notched plates under tension

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Science China(Physics,Mechanics & Astronomy) 2014年第9期57卷 1751-1757页

作者： AfSHAr r BErTO f University of Padova Department of Management and Engineering

By using the finite element method,three-dimensional models of a number of periodic blunt and sharp notches subjected to tension loading are *** aim of this research is to investigate the thickness effect on the location of maximum stress and notch stress intensity factor(NSIf)of corresponding blunt and sharp periodic notches *** this aim,different number of periodic notches as well as different notch opening angles are *** for two-dimensional plates weakened by periodic notches some results are available in the literature,this paper first faces the problem of three-dimensional cases.A total of about 100 geometrical configurations are *** is found that,the effect of plate thickness of periodic notched components can be characterized by the relative value with respect to the depth of the notch(H/t).for the blunt periodic notches with relatively higher values of H/t ratio,the value of the maximum tensile stress is located near the free *** the contrary for lower values of H/t,it is placed at the middle *** same behaviour is observed for sharp periodic notches in terms of notch stress intensity factors.

关键词： periodic notches three-dimensional problems notch stress intensity factor stress concentration factor

Modelling ballistic impact on military helmets:The relevance of projectile plasticity

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Defence Technology（防务技术） 2021年第5期17卷 1699-1711页

作者： A.Caçoilo r.Mourao f.Teixeira-Dias A.Azevedo f.Coghe r.A.f.Valente School of Engineering The University of EdinburghEdinburghEH93FGUK Dept.Weapon Systems and Ballistics Royal Military AcademyBrusselsBelgium Centre for Mechanical Technology and Automation Department of Mechanical EngineeringUniversity of AveiroPortugal

The need to develop armour systems to protect against attacks from various sources is increasingly a matter of personal,social and national *** develop innovative armour systems it is necessary to monitor developments being made on the type,technology and performance of the threats(weapons,projectiles,explosives,etc.) Specifically,the use of high protection level helmets on the battlefield is *** development of evaluation methods that can predict injuries and trauma is therefore of major ***,the risk of injuries or trauma that can arise from induced accelerations is an additional *** develop new materials and layouts for helmets it is necessary to study the effects caused by ballistic impacts in the human head on various *** use of numerical simulation is a fundamental tool in this *** work here presented focuses on the use of numerical simulation(finite elements analysis) to predict the consequences of bullet impacts on military helmets on human *** main objectives are to assess the level and probability of head trauma using the Head Injury Criterion,caused by the impact of a 9 mm NATO projectile on a PASGT helmet and to quantify the relevance of projectile plasticity on the whole modelling *** accelerations derived from the impact phenomenon and the deformations caused on the helmet are evaluated using fully three-dimensional models of the helmet,head,neck and *** studies are done at impact angles ranging from 0 to 75°.results are presented and discussed in terms of HIC and probability of acceleration induced trauma *** comparison analyses are done using a rigid and a deformable projectile and it is observed that plastic deformation of the projectile is a significant energy dissipation mechanism in the whole impact process.

关键词： Ballistic impact Helmet impact Plasticity finite element analysis Injury Trauma HIC

Modeling of unidirectional blood flow in microvessels with effects of shear-induced dispersion and particle migration

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Applied Mathematics and Mechanics(English Edition) 2022年第10期43卷 1585-1600页

作者： G.rOUrE f.r.CUNHA Laboratory of Microhydrodynamics and rheology Department of Mechanical EngineeringUniversity of BrasíliaBrasília70910900Brazil Department of Chemical and Biological Engineering University of Colorado BoulderBoulder803090596USA

A cell-free layer,adjacent to microvessel walls,is present in the blood flow in the microcirculation *** layer is of vital importance for the transport of oxygen-saturated red cells to unsaturated *** this work,we first discuss the physics of formation of this cell-free layer in terms of a balance between the shear-induced dispersion and particle *** this end,we use high-viscosity drops as prototypes for cells,and discuss our results in terms of physical parameters such as the viscosity ratio and the capillary *** also provide a short-time analysis of the transient drift-dispersion equation,which helps us better explain the formation process of the cell-free ***,we present models for investigating the blood flow in two different scales of *** investigating the blood flow in venules and arterioles,we consider a continuous core-flow model,where the core-flow solution is considered to be a Casson fluid,surrounded by a small annular gap of Newtonian plasma,corresponding to the cell-free *** also propose a simple model for smaller vessels,such as capillaries,whose diameters are of a few *** this lower-bound limit,we consider a periodic configuration of aligned,rigid,and axi-symmetric cells,moving in a Newtonian *** this regime,we approximate the fluid flow using the lubrication *** intrinsic viscosity of the blood is theoretically predicted,for both the lower and upper-bound regimes,as a function of the non-dimensional vessel diameter,in good agreement with the previous experimental *** compare our theoretical predictions with the experimental data,and obtain qualitatively good agreement with the well-known fåhræus-Lindqvist effect.A possible application of this work could be in illness diagnosis by evaluating changes in the intrinsic viscosity due to blood abnormalities.

关键词： theory flow dispersion

Effects of Mach numbers on Magnus induced surface pressure

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Chinese Journal of Aeronautics 2020年第12期33卷 3058-3072页

作者： f.ASKArY M.r.SOLTANI Department of Aerospace Engineering Sharif UniversityTehran P.O.B ***Iran Department of Aeronautics and Astronautics University of WashingtonSeattle BOX 352400USA

Experimental and numerical methods were used to investigate the Magnus phenomena over a spinning *** pressure force acting on the surface of a spinning projectile was measured for various cases by employing a relatively novel experimental technique.A set of miniature pressure sensors along with a data acquisition board,battery and storage memory were placed inside a spinning model and the surface pressure were obtained through a remotely controlled *** pressures of the model for both rotational and static conditions were obtained at two different free stream Mach numbers of 0.4 and 0.8 and at different angles of *** results showed the ability of this new test method to measure the very small Magnus force via surface pressures over the *** results provide a deep insight into the flow structure and illustrate changes in the cross-flow separation locations as a result of *** results were obtained by the numerical simulations and were compared with the experimental data.

关键词： Magnus effect Spinning projectile Surface pressure Wind tunnel

Approaching nuclei through multiple perspectives and diverse models： Patterns, symmetries, interactions

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frontiers of physics 2018年第6期13卷 29-38页

作者： r. f. Casten Wright Nuclear Structure Laboratory Yale University New Haven CT 06520 USA Michigan State University- frIB East Lansing MI USA

Nuclei are complex objects yet display remarkable simplicities and regular patterns. The study of these and their origins has long been one of the twin pillars of nuclear structure research. We will discuss the behavior of atomic nuclei from this point of view. A key element will be the advantages of looking at the same data from different perspectives and of inter-relating these perspectives.

关键词： nuclear structure simple patterns and symmetries diverse perspectives and models emergence of collectivity residual interactions

Movement analysis in the diagnosis and management of Parkinson’s disease

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Neural regeneration research 2025年第2期20卷 485-486页

作者： Johannes Burtscher Nicolas Bourdillon Jules MJanssen Daalen Aurélien Patoz Julien fBally Martin Kopp Davide Malatesta Bastiaan rBloem Institute of Sport Sciences University of LausanneLausanneSwitzerland radboud University Medical Center Department of NeurologyDonders Institute for BrainCognition and BehaviorCenter of Expertise for Parkinson and Movement DisordersNijmegenThe Netherlands radboud University Medical Center Department of Medical BioSciencesNijmegenThe Netherlands research and Development Department Volodalen Swiss Sport LabAigleSwitzerland Service of Neurology Department of Clinical NeurosciencesLausanne University Hospital(CHUV)and University of Lausanne(UNIL)LausanneSwitzerland Department of Sport Science University of InnsbruckInnsbruckAustria

Challenges in the diagnosis and treatment of Parkinson’s disease:Parkinson’s disease(PD)is an increasingly prevalent neurodegenerative disease,at first sight primarily characterized by motor symptoms,although non-motor symptoms also constitute a major part of the overall ***,this disease cannot be diagnosed reliably until a large part of the vulnerable dopaminergic neurons has been irretrievably lost,and the disease progresses *** biological criteria for PD have been proposed recently and might eventually improve early diagnosis,but they require further validation,and their use will initially be restricted to a research environment(Darweesh et al.,2024).

关键词： diagnosis Clinical eventually

Dipole and Quadrupole Electroexcitations of the Isovector T = 1 Particle-Hole States in ^12C

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Chinese Physics Letters 2006年第10期23卷 2699-2702页

作者： f.A.Majeed r.A.radhi Instituto de fisica Universidade Federal do Rio de Janeiro C.P. 68528 21941-972 Rio de Janeiro RJ Brazil Department of Physics College of Science Baghdad University Baghdad IRAQ

Electroexcitations of the dominantly T=1 particle-hole states of ILC are studied in the framework of the harmonic oscillator shell model. All possible T=1 single-particle-hole states of all allowed angular momenta are considered in a basis including single-particle states up to the 1f-2p shell. The Hamiltonian is diagonalized in this space in the presence of the modified surface delta interaction. Correlation in the ground state wavefunctions by mixing more than one configuration is considered and shows a major contribution that leads to enhance the calculations of the form factors. A comparison with the experiment shows that this model is able to fit the location of states and a simple scaling of the results give a good fit to the experimental form factors.

关键词： Ground state

Assessment of rockburst hazard by quantifying the consequence with plastic strain work and released energy in numerical models

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International Journal of Mining Science and Technology 2019年第1期29卷 93-97页

作者： f.Wang r.Kaunda Mining Engineering Department Colorado School of Mines

Quantifying the rockburst consequence is of critical importance to reduce the hazards with preventative measures in underground mines and deep tunnels. Contours of energy components within a pillar model are plotted at different rockmass damage stages, and plastic strain work and released energy are proposed as indicators of rockmass damage consequence. One pillar model under different loading stiffness is simulated to assess indicators of pillar burst and the resulting damages. The results show the rockmass damage under soft loading stiffness has larger magnitude of plastic strain work and released energy than that which is under stiff loading stiffness, indicating the rockburst consequence can be quantified with plastic strain work and released energy in numerical models. With the quantified rockburst consequence,preventative measures can be taken to avoid severe hazards to mine safety.

关键词： Unstable rock failure rock burst Energy mechanism Numerical modeling released energy