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CES Transactions on Electrical Machines and Systems 2024年第1期8卷 86-102页

作者： g.Kovács the ganz Electric Works BudapestHungary

The harmonics that appear in the squirrel cage asynchronous machine have been discussed in great detail in the literature for a long time. However, the systematization of the phenomenon is still pending, so we made an attempt to fill this gap in the previous parts of our study by elaborating formulas for calculation of parasitic torques. It was a general demand among those who work in this field towards the author to verify his formulas with measurements. In the literature, it seems,only one detailed, purposeful series of measurements has been published so far, the purpose of which was to investigate the effect of the number of rotor slots on the torque-speed characteristic curve of the machine. The main goal of this study is to verify the correctness of the formulas by comparing them with the referred series of measurements. relying on this, the expected synchronous parasitic torques were developed for the frequently used rotor slot numbers-as a design guide for the ***, together with our complete table for radial magnetic pull published in our previous work, the designer has all the principles, data and formulas available for the right number of rotor slots for his given machine and for the drive system. This brings this series of papers to an end.

关键词： Asynchronous parasitic torques Induction motor Squirrel cage rotor Space harmonics Synchronous parasitic torques

The magnetosheath at high spectral resolution

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Earth and Planetary Physics 2024年第1期8卷 234-246页

作者： K.D.Küntz D.Koutroumpa W.r.Dunn A.Foster F.S.Porter D.g.Sibeck B.walsh The Henry A.rowland Department of Physics and Astronomy Johns Hopkins University3701 San Martin DriveBaltimoreMD21218USA NASA goddard Space Flight Center 8800 Greenbelt RoadGreenbeltMD 20771USA LATMOS-OVSQ CNRSUVSQ Paris-SaclaySorbonne Université11 Boulevard d’Alembert78280GuyancourtFrance Department of Physics and Astronomy University College LondonLondonUK The Centre for Planetary Science at UCL/Birkbeck Gower StreetLondon WC1E 6BTUK Center for Astrophysics Harvard University&Smithsonian Institution60 Garden StreetCambridgeMA 02138USA Center for Space Physics Boston University110 Cummington MallBostonMAUSA

While we eagerly anticipate SMILE’s(Solar wind Magnetosphere Ionosphere Link Explorer)unprecedented X-ray observations of the Earth’s magnetosheath and the initiation of a new era of magnetospheric research,it seems appropriate to look ahead to the abilities of the next generation of astrophysics *** these,the Line Emission Mapper(LEM),a large aperture micro-calorimeter based mission,is currently planned to be able to observe the magnetosheath at high spectral resolution(~2 eV).With a field of view of~30′,LEM will allow higher spatial resolution and higher cadence measurement of the motion of a very small portion of the magnetopause over relatively short periods of time(multiple hours),complementing SMILE’s global ***’s strength is its spectral *** will be able to measure the abundance of a broad range of elements and ionization states,many of which are inaccessible to current in situ instruments,and will be able to separate the emission from the magnetosheath from the emission from the cosmic X-ray background using the difference in their relative velocities.

关键词： magnetosheath charge exchange solar wind abundances

Neuroimaging in atypical normal tension glaucoma:debating routine implementation in the absence of classic neurological findings

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International Journal of Ophthalmology(English edition) 2024年第3期17卷 509-517页

作者： Umay güvenç gülizar Demirok güner Üney Selma Uzman Ophthalmology Department Ankara Training and Research HospitalAnkara 06230Turkey

●AIM:To assess the necessity of neuroimaging in patients with neurological or atypical findings of normal tension glaucoma(NTg)who do not exhibit typical glaucoma manifestations.●METHODS:A retrospective analysis was conducted on 90 atypical NTg patients who underwent cranial magnetic resonance imaging(MrI)due to atypical *** demographic characteristics,clinical parameters,and radiological findings were recorded.●rESULTS:Among the patients,66.7%had abnormal radiology results,with the most common findings being gliosis(34.4%),sequelae of cerebrovascular events and vascular malformations(14.4%),and benign intracranial mass lesions(11%).Non-glaucomatous visual field defects were more frequently observed in patients with abnormal neuroimaging ***,there were no significant differences in intraocular pressure,optic disc parameters,retinal nerve fiber layer thickness,and visual field indices between patients with normal and abnormal radiological *** mean age of the patients was ***,there was a significant age difference,with the abnormal radiology group having a higher median age(P=0.021).●CONCLUSION:The study highlights the importance of cranial imaging in older NTg patients to detect underlying pathologies and prevent *** suggests that neuroimaging may be warranted in NTg patients with atypical visual field defects incompatible with ***,routine neuroimaging in all NTg patients without classic neurological signs may not be necessary.

关键词： normal tension glaucoma neuroimaging atypical visual field defects

Combustion characteristics of low-quality lignite for different bed material sphericities in a circulating fluidized bed boiler:A numerical study

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Particuology 2024年第7期90卷 364-382页

作者： Barış gürel gülşah Karaca Dolgun Osman İpek Ali Keçebaş Department of Mechanical Engineering Engineering FacultySüleyman Demirel UniversityÇünürIspartaTurkey Department of Energy Systems Engineering Technology FacultyMuğla SıtkıKoçman UniversityKötekliMenteşeMuğlaTurkey

This study delves into the combustion behavior of various lignite types within a circulating fluidized bed boiler(CFBB),with a primary focus on the impact of different bed material sphericity ratios(0.5,0.7,and 0.9).Utilizing bed material with a sphericity ratio of 0.9 sourced from theÇan power plant and verified through experimentation,the research reveals several key ***,furnace temperatures tended to rise with higher sphericity ratios,albeit with variations between lignite types,particularly highlighting the complexity of this relationship in the case of gLI-Tunçbilek *** levels in the combustion chamber remained consistent across different sphericity ratios,indicating minimal influence on pressure *** combustion efficiency,especially at the bottom of the boiler,was observed at lower sphericity levels(0.5 and 0.7)forÇan lignite,as reflected in CO_(2) mole *** NO_(x) emissions generally decreased with lower sphericity,the sensitivity to sphericity varied by lignite type,with Ilgın lignite showcasing low NO_(x) but high SO_(2) emissions,underscoring the intricate interplay between lignite properties,sphericity,and ***,this study advances our understanding of CFBB combustion dynamics,offering insights valuable for optimizing performance and emissions control,particularly in lignite-based power.

关键词： Circulating fluidized bed boiler Computational particle fluid dynamics method Particle sphericity ratios NO_(x)and SO_(2)emissions Energy production efficiency

Physico-Chemical Characterization of Wood Ash for Agronomic Purposes

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Journal of Agricultural Chemistry and Environment 2024年第2期13卷 235-250页

作者： Ayi Kévin Ajavon Bassaï Magnoudéwa Bodjona Diyakadola Dihéénane Bafai Laboratory waste Management Treatment and Recovery (GTVD) Faculty of Sciences University of Lome Lome Togo

The oil refinery of the food products company SOPAL, located in the port area of TOgO, produces an average of 200 kg of eucalyptus wood ash per day. This ash is stored in large quantities within the premises of the refinery, without any disposal solution. The aim of this study is to identify the physico-chemical properties of SOPAL’s wood ash for agronomic valorization. Physico-chemical analyses reveal the presence of major and secondary elements such as potassium (15.71 g/kg DM), phosphorus (27.90 g/kg DM), calcium (9.76 g/kg DM), magnesium (0.03 g/kg DM), sodium (1.24 g/kg DM), iron (1.49 g/kg DM) and manganese (7.82 g/kg DM). The pH is alkaline (12.97) with fairly high conductivity (24.10 mS/Cm). Heavy metals identified are cobalt (0.19 mg/kg DM), cadmium (0.10 mg/kg DM), lead (1.14 mg/kg DM), copper (19.77 mg/kg DM) and nickel (12.82 mg/kg DM). The results show that the ash contains considerable amount of major and secondary elements for agronomic uses.

关键词： Industry Wood Ash Heavy Metals Valorization

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

Electrochemical realization of 3D Interconnected MoS_(3)/PPy Nanowire Frameworks as Sulfur-Equivalent Cathode Materials for Li-S Batteries

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Energy & Environmental Materials 2024年第2期7卷 9-17页

作者： Hongtao Yu Andreas Siebert Shilin Mei raul garcia-Diez roberto Félix Ting Quan Yaolin Xu Johannes Frisch regan g.Wilks Marcus Bär Chun Pei Yan Lu Department for Electrochemical Energy Storage Helmholtz-Zentrum Berlin für Materialien und Energie GmbH(HZB)Hahn-Meitner Platz 114109 BerlinGermany guangdong Province Key Laboratory of Durability for Marine Civil Engineering School of Civil EngineeringShenzhen UniversityShenzhenGuangdong 518060China Department of Interface Design HZBAlbert-Einstein-Str.1512489 BerlinGermany Energy Materials In-Situ Laboratory Berlin(EMIL) Albert-Einstein-Str.1512489 BerlinGermany Helmholtz-Institute Erlangen-Nürnberg for renewable Energy(HI ErN) Albert-Einstein-Str.1512489 BerlinGermany Department of Chemistry and Pharmacy Friedrich-Alexander-Universität Erlangen-NürnbergEgerlandstr.391058Erlangen Germany Institute of Chemistry University of Potsdam14467Potsdam Germany

The development of freestanding and binder-free electrode is an effective approach to perform the inherent capacity of active materials and promote the mechanism study by minimizing the interference from ***,we construct a freestanding cathode composed of MoS_(3)/PPy nanowires(NWs)deposited on porous nickel foam(NF)(MoS_(3)/PPy/NF)through electrochemical methods,which can work efficiently as sulfur-equivalent cathode material for Li-S *** structural stability of the MoS_(3)/PPy/NF cathode is greatly enhanced due to its significant tolerance to the volume expansion of MoS_(3)during the lithiation process,which we ascribe to the flexible 3D framework of PPy NWs,leading to superior cycling performance compared to the bulk-MoS_(3)/NF *** the interference of binder and carbon additives,the evolution of the chemical and electronic structure of Mo and S species during the discharge/charge was studied by X-ray absorption near-edge spectroscopy(XANES).The formation of lithium polysulfides was excluded as the driving cathode reaction mechanism,suggesting the great potential of MoS_(3)as a promising sulfur-equivalent cathode material to evade the shuttle effect for Li-S *** present study successfully demonstrates the importance of structural design of freestanding electrode enhancing the cycling performances and revealing the corresponding mechanisms.

关键词： 3D-Network electrochemical lithium-sulfur battery MoS_(3) PPy

Assessing the biennial conference on science and technology (BICOST IX) 2023 technical output on renewable energy, energy storage, and green hydrogen in line with UN SDg commitments

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CLEAN ENErgY 2024年第2期8卷 85-88页

作者： Silva, S. K. B. D. Piyumali, K. g. D. Perera, rasitha Thilini Suranjana Kaluarachchi, K. D. K. g. Munagamage, Thilini Ahammed, r. M. r. Piyankarage, C. S. P. Shahmy, Seyed Karunaratne, Veranja Natl Sci & Technol Commiss Sri Lanka Colombo Sri Lanka Sri Lanka Technol Campus Padukka 10500 Sri Lanka Univ Peradeniya Peradeniya Sri Lanka

The development, production and utilization of renewable energy, energy storage and green hydrogen and the associated technologies in Sri Lanka have great potential to contribute to the United Nations' Sustainable Development goals (SDgs). The island aims to achieve 70% electricity generation from renewable energy sources by 2030 (within the target of 40% utilization of renewable energy sources for the entire energy generation of the country by 2030). The power sector has to invest US$11 billion from 2023 to 2030 to contribute to reaching this target. This commentary aims to provide a critical perspective on the recommendations of the report from the National Science and Technology Commission's 9th biennial conference in 2023 on science and technology, the sub-thematic technical report on clean energy, energy storage and green hydrogen in line with the SDgs in the Sri Lankan context. The technical report provides insightful recommendations for Sri Lanka's energy sector under three main sections: renewable energy, energy storage and green hydrogen. Also, it explores the potential of various renewable energy sources, energy storage systems and green hydrogen as sustainable solutions to address the country's energy challenges while emphasizing the spillover effects of them, which could contribute to the enterprise's job creation and uplift the economy. This commentary provides a critical perspective on clean energy, energy storage and green hydrogen in line with the United Nations SDgs in the Sri Lankan context based on a recent report from the National Science and Technology Commission of Sri Lanka. graphical Abstract

关键词： renewable energy energy storage green hydrogen sustainable development goals Sri Lanka social economic environmental sustainable affordable

LKB1 depletion-mediated epithelial-mesenchymal transition induces fibroblast activation in lung fibrosis

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genes & Diseases 2024年第3期11卷 417-426页

作者： Zijian Xu Elizabeth r.Davies Liudi Yao Yilu Zhou Juanjuan Li Aiman Alzetani Ben g.Marshall David Hancock Tim wallis Julian Downward rob M.Ewing Donna E.Davies Mark g.Jones Yihua wang Biological Sciences Faculty of Environmental and Life SciencesUniversity of SouthamptonSouthampton SO171BJUK clinical and Experimental Sciences Faculty of MedicineUniversity of SouthamptonSouthampton SO166YDUK Institute for Life Sciences University of SouthamptonSouthampton SO171BJUK NIHr Southampton Biomedical research Centre University Hospital SouthamptonSouthampton SO166YDUK University Hospital Southampton Southampton SO166YDUK Oncogene Biology The Francis Crick InstituteLondon NW11ATUK

The factors that determine fibrosis progression or normal tissue repair are largely *** previously demonstrated that autophagy inhibition-mediated epithelial-mesenchymal transition(EMT)in human alveolar epithelial type Il(ATIl)cells augments local myofibroblast differentiation in pulmonary fibrosis by paracrine ***,we report that liver kinase B1(LKB1)inactivation in ATIl cells inhibits autophagy and induces EMT as a *** IPF lungs,this is caused by the down-regulation of CAB39L,a key subunit within the LKB1 complex.3D co-cultures of ATIl cells and MrC5 lung fibroblasts coupled with rNA sequencing(rNA-seq)confirmed that paracrine signaling between LKB1-depleted ATIl cells and fibroblasts augmented myofibroblast ***,these data suggest that reduced autophagy caused by LKB1 inhibition can induce EMT in ATIl cells and contribute to fibrosis via aberrant epithelial-fibroblast crosstalk.

关键词： CAB39L Crosstalk EMT LKB1 Pulmonary fibrosis