检索结果-南通市图书馆

FEA-based Geometrical Modification of Switched reluctance Motor for radial Force reduction

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Electrical Engineering 2024年第1期10卷 124-135页

作者： rani S Jayapragash r School of Electrical Engineering Vellore Institute of TechnologyChennai 600127India

Switched reluctance motors(SrMs)are becoming increasingly popular in the automotive sector owing to their robust ***,SrMs are preferred particularly for EV applications owing to their fault tolerance,magnet-free structure,and high power/torque *** main concerns of SrM compared to other machines include torque ripple and *** primary cause of vibration is the radial force created by the SrM.A geometry-based modification of the SrM to reduce the radial force without significantly changing the average torque produced is *** primary goal is to design a 4-phase,8/6 SrM with a lower radial *** possible geometrical alterations are proposed:one with square windows and the other with circular holes on the rotor *** windows are sized and positioned to avoid flux *** criteria are developed for the optimal window size and *** element analysis(FEA)modelling of the SrM is used to validate its *** FEA results are compared with the performance parameters obtained using the analytical *** the multiphysics design tool ANSYS to obtain the natural frequencies and associated deformations through modal *** to the conventional geometry,the radial force is significantly reduced by providing windows.

关键词： 8/6 SrM radial force modal analysis FEA analysis natural frequencies SrM with windows

Transcranial photobiomodulation for the brain: a wide range of clinical applications

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural regeneration research 2024年第3期19卷 483-484页

作者： Michael r.Hamblin laser research Centre Faculty of Health ScienceUniversity of Johannesburg-Doornfontein CampusDoornfonteinSouth Africa

Photobiomodulation therapy(PBMT)is a rapidly growing approach to the healing,stimulation,protection,and regeneration of many human organs and tissue *** started in the 1960s as low-level laser therapy for wound healing,but since then the introduction of light-emitting diodes(lEDs)has dramatically increased the number of applications and reports of positive *** generally uses red(620-700 nm)and/or near-infrared(780-1270 nm)wavelengths of light at an intensity that causes no tissue heating,and its activity is based on well-established biological and cellular mechanisms(de Freitas and Hamblin,2016).While laser therapists continue to use various types of laser in their office practice,lEDs are ideally suited for home use devices because they are completely safe and without any known significant adverse *** the various body parts on which PBMT has been shown to exert beneficial effects,the brain stands out as perhaps the most promising *** has been shown to reduce neuroinflammation,while increasing mitochondrial function,oxygen consumption,and blood flow within the brain(Hamblin,2016).Moreover,PBMT can stimulate the processes of synaptogenesis,neurogenesis,and neuroplasticity thus helping the brain to heal itself.

关键词： healing stimulation wound

Approach for C_(1)to C_(2)products commencing from carbon dioxide:A brief review

在线全文

学校读者我要写书评

暂无评论

Petroleum 2024年第3期10卷 373-398页

作者： G.r.Dey radiation and Photochemistry Division Bhabha Atomic Research CentreTrombayMumbai 400085India Homi Bhabha National Institute AnushaktinagarMumbai 400094India

The carbon dioxide(CO_(2))conversion to useable compounds remains a great contest to scientists,engineers,and environmentalists with regard to the reverse of the oxidative degradation of *** conversion is essential for the development of complementary fuels and raw materials for various industries,which in turn will help in avoiding the drastic increase in tropospheric temperature due to greenhouse effect leading to global *** solar energy is the earth's essential power source along with the other various forms of energy for example fossil fuels,hydropower,wind,and biomaterials,*** final goal is to establish the artificial photosynthesis,which can be replicated thru various chemical reduction techniques of CO_(2)by employing appropriate photo-,thermal-and electro-catalysts in order to produce different one carbon atom(C_(1))and higher carbon atoms containing ***,the utilization of clean and sustainable CO_(2)towards high-value products is of great interest today due to the recognized environmental worries and subsequent lessening of the fossil fuels utilization load to meet the energy demand of *** way,solar energy can directly and/or indirectly be altered and stored in chemical energy form for industrial as well as societal *** this article our endeavor is to summarize the advances in CO_(2)chemical reduction research area till date especially in free radical-based methods such as electrochemical,photochemical and plasma chemical for the development of carbon species up to two carbon(C_(2))atoms containing products perceived in the chemical reduction of CO_(2).The author hopes that this piece of work will be helpful to researchers and readers who are focused on the field of CO_(2).

关键词： Photocatalysis Electrocatalysis Plasmolysis Thermolysis Carbon dioxide Chemical reduction

First-principles calculation on the electronic structures, phonon dynamics, and electrical conductivities of Pb_(10)(PO_(4))_(6O) and Pb_(9)Cu(PO_(4))_(6O) compounds

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2024年第6期173卷 218-224页

作者： l.Y.Hao E.G.Fu State Key laboratory of Nuclear Physics and Technology Department of Technical PhysicsSchool of PhysicsPeking UniversityBeijing 100871China

Superconducting materials with high critical temperature have the potential to revolutionize many fields,including military,electronic communications,and power ***,scientists around the world have been tirelessly working with the ultimate goal of achieving high-temperature *** 2023,a preprint by lee et *** South Korea claimed the discovery of ultra-high-temperature superconductivity with a critical temperature of up to 423 K in Cu-doped lead-apatite(lK-99)(arXiv:2307.12008,arXiv:2307.12037),which caused a worldwide sensation and ***,the electronic structures,phonon dynamics,and electrical conductivities of lK-99 and its parent compound lead-apatite have been calculated using first-principles *** results show that the lead-apatite compound and the lK-99 compound are insulator and half-metal *** flat band characteristic is consistent with previous *** electrical conductivity of the lK-99 compound shows two extreme points,and the electrical conductivity along the C-axis increases significantly after 400 *** phonon dispersion spectra of the compounds were investigated,demonstrating their dynamic instability.

关键词： Superconductivity lK-99 lead-apatite First-principles calculation

Comparative analysis of microstructure,mechanical,and corrosion properties of biodegradable Mg-3Y alloy prepared by selective laser melting and spark plasma sintering

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Magnesium and Alloys 2024年第4期12卷 1496-1510页

作者： P.Minárik M.Zemková S.Šašek J.Dittrich M.Knapek F.lukáˇc D.Koutný J.Jaroš r.Král Faculty of Mathematics and Physics Charles UniversityKe Karlovu 5Praha 12116Czech Republic research Centre University ofŽilinaUniverzitná8215/1Žilina 01026Slovakia Institute of Plasma Physics of the Czech Academy of Sciences Za Slovankou 1782/318200 Praha 8Czech Republic Institute of Machine and Industrial Design Brno University of TechnologyTechnická2896/2Brno 61669Czech Republic

This work explored possibilities of biodegradable magnesium alloy Mg-3Y preparation by two modern powder metallurgy techniques–spark plasma sintering(SPS)and selective laser melting(SlM).The powder material was consolidated by both methods utilising optimised parameters,which led to very low porosity(∼0.3%)in the SlM material and unmeasurably low porosity in the SPS *** main aim of the study was the thorough microstructure characterisation and interrelation between the microstructure and the functional properties,such as mechanical strength,deformability,and corrosion *** materials showed comparable strength of∼110 MPa in tension and compression and relatively good deformability of∼9%and∼21%for the SlM and SPS materials,*** corrosion resistance of the SPS material in 0.1 M NaCl solution was superior to the SlM one and comparable to the conventional extruded *** digital image correlation during loading and the cross-section analysis of the corrosion layers revealed that the residual porosity and large strained grains have the dominant negative effect on the functional properties of the SlM *** the other hand,one of the primary outcomes of this study is that the SPS consolidation method is very effective in the preparation of the W3 biodegradable alloy,resulting in material with convenient mechanical and degradation properties that might find practical applications.

关键词： Magnesium Yttrium Powder metallurgy Microstructure Mechanical strength Corrosion resistance

Assessment of portable FTIr and raman spectroscopy for the detection of 2,3-dimethyl-2,3-dinitrobutane(DMDNB)in plastic explosives

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4期34卷 11-18页

作者： Jacky Cailes robert Dunsmore Kathryn l.linge ChemCentre PO Box 1250PerthAustralia

The Marplex Convention was established to prevent the manufacture of unmarked plastic explosives and stipulates that a volatile detection agent must be added at the time of ***,to-date,laboratory testing remains the internationally accepted practice for identifying and quantifying the taggants stipulated in the *** this project,portable FTIr and raman instruments were tested for their ability to detect 2,3-dimethyl-2,3-dinitrobutane(DMDNB),the chemical marker incorporated in plastic explosives that are manufactured within *** both FTIr and raman instruments detected solid DMDNB(98%purity),field analysis of plastic explosives at an Australian Defence establishment showed that both FTIr and raman spectra were matched the relevant explosive(rDX or PETN),rather than the DMDNB *** all three plastic explosives tested,the concentration of DMDNB was measured by SPME-GC-MS to be between 1.8 and 2%,greater than the minimum 1%concentration stipulated by the Marplex *** testing with a plastic explosive analogue confirmed that the minor absorption peaks that would characterize low concentrations of DMDNB were masked by absorption bands from other compounds within the ***,while both FTIr and raman spectroscopy are suitable for detection of plastic explosives,neither rely on the presence of DMDNB for *** is likely that similar results would be found for other taggants stipulated by the Marplex Convention,given they are also present in concentrations less than 1%.

关键词： Explosive ICAO taggants 2,3-Dimethyl-2,3-dinitrobutane(DMDNB) Fourier transform infrared(FTIr) raman

Nonaqueous potassium-ion full-cells:Mapping the progress and identifying missing puzzle pieces

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2024年第6期93卷 384-399,I0010页

作者： Badre larhrib louiza larbi lénaïc Madec Universite de Pau et des Pays de l’Adour E2S UPPACNRSIPREMPauFrance Universitéde Haute-Alsace Institut de Science des Matériaux de Mulhouse(IS2M)CNRS UMR 7361F-68100 MulhouseFrance Universitéde Strasbourg F-67081 StrasbourgFrance réseau sur le Stockage Electrochimique de l’Energie CNRS FR3459AmiensFrance Institut des Matériaux Jean rouxel(IMN) CNRS UMR 6502Univ.Nantes44322 Cedex 3 NantesFrance

This review addresses the growing interest for potassium-ion full-cells(KIFCs)in view of the transition from potassium-ion half-cells(KIHCs)toward commercial K-ion batteries(KIBs).It focuses on the key parameters of KIFCs such as the electrode/electrolyte interfaces challenge,major barriers,and recent advancements in *** strategies for enhancing KIFC performance,including interfaces co ntrol,electrolyte optimization,electrodes capacity ratio,electrode material screening and electrode design,are *** review highlights the need to evaluate KIBs in full-cell configurations as half-cell results are strongly impacted by the K metal *** also emphasizes the importance of understanding solid electrolyte interphase(SEI)formation in KIFCs and explores promising nonaqueous as well as quasiand all-solid-state electrolytes *** review thus paves the way for practical,cost-effective,and scalable KIBs as energy storage systems by offering insights and guidance for future research.

关键词： K-ion full-cells Potassium-ion batteries Cross-talk Solid-state batteries Potassium reactivity Electrolyte design Electrode design

Guaranteed Cost Attitude Tracking Control for Uncertain Quadrotor Unmanned Aerial Vehicle Under Safety Constraints

在线全文

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1447-1457页

作者： Qian Ma Peng Jin Frank l.lewis School of Automation Nanjing University of Science and TechnologyNanjing 210094China UTA research Institute University of Texas at ArlingtonFort WorthTexas 76118 USA IEEE

In this paper,guaranteed cost attitude tracking con-trol for uncertain quadrotor unmanned aerial vehicle(QUAV)under safety constraints is ***,an augmented system is constructed by the tracking error system and reference *** transformation aims to convert the tracking control prob-lem into a stabilization control ***,control barrier function and disturbance attenuation function are designed to characterize the violations of safety constraints and tolerance of uncertain disturbances,and they are incorporated into the reward function as penalty *** on the modified reward function,the problem is simplified as the optimal regulation problem of the nominal augmented system,and a new Hamilton-Jacobi-Bellman equation is ***,critic-only rein-forcement learning algorithm with a concurrent learning tech-nique is employed to solve the Hamilton-Jacobi-Bellman equa-tion and obtain the optimal *** proposed algorithm can not only ensure the reward function within an upper bound in the presence of uncertain disturbances,but also enforce safety *** performance of the algorithm is evaluated by the numerical simulation.

关键词： Attitude tracking control quadrotor unmanned aerial vehicle(QUAV) reinforcement learning safety constraints uncertain disturbances.

Approximate contact solutions for non-axisymmetric homogeneous and power-law graded elastic bodies:A practical tool for design engineers and tribologists

在线全文

学校读者我要写书评

暂无评论

Friction 2024年第2期12卷 340-355页

作者： Valentin l.POPOV Qiang lI Emanuel WIllErT Institute of Mechanics Technische Universität BerlinBerlin 10623Germany

In two recent papers,approximate solutions for compact non-axisymmetric contact problems of homogeneous and power-law graded elastic bodies have been suggested,which provide explicit analytical relations for the force–approach relation,the size and the shape of the contact area,as well as for the pressure distribution *** solutions were derived for profiles,which only slightly deviate from the axisymmetric *** the present paper,they undergo an extensive testing and validation by comparison of solutions with a great variety of profile shapes with numerical solutions obtained by the fast Fourier transform(FFT)-assisted boundary element method(BEM).Examples are given with quite significant deviations from axial symmetry and show surprisingly good agreement with numerical solutions.

关键词： normal contact non-axisymmetric indenter extremal principle generalized method of dimensionality reduction(MDr) functional elastic grading