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Thermo-Electrochemical Processes of the Earth’s Degassing Creating Geomagnetic Field and Changing Its Value and Direction (Thermodynamic Approach)

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International Journal of Geosciences 2014年第10期5卷 1219-1230页

作者： alexander vol OSHADI Drug Administration Ltd. Rehovot Israel

The currently accepted theory of self-exciting dynamo generating magnetic field of the Earth and its shortage of energy is critically reviewed. Based on thermodynamic approach, a new hypothesis of the Earth’s magnetic field, created by thermo-electrochemical processes of the Earth’s degassing, gravitational differentiation and their energy, is proposed. The ion-exchange, extraction and solidification are sources of the ionic currents on solid core and lower mantle boundaries. These currents are carried by thermo-chemical flows, which create the primary exciting magnetic field. This field is amplified mostly by thermoelectricity generated by heat flow thus improving the heat and matter transport from the Earth’s core and lower mantle to surface. Migration of the solidification zones and inner core precession are the main causes of changes of the main magnetic field intensity and reversals of its polarity.

关键词： Degassing Gravitational Differentiation Electrochemistry Thermoelectricity Geomagnetism

Hypothetical Physics and Chemistry of volcanic Eruptions: The Doorway to Their Prediction

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International Journal of Geosciences 2019年第4期10卷 377-404页

作者： Arie Lev Gilat Strachimir Cht Mavrodiev alexander vol Geological Survey of Israel (Ret.) Jerusalem Israel INRNE-BAS Sofia Bulgaria OSHADI Drug Administration Ltd. Rehovot Israel

This article presents a further development of the hypotheses concerning the possibility of predicting (“tectonic”) earthquakes [1]. Those hypotheses are based on the conversion of all types of released energy into heat and active chemical substances. One of the important sources of this phenomenon is the release of the latent energy trapped and stored during the Earth’s accretion. The latent energy of primordial hydrogen and helium escaping from the Earth’s core and lower mantle causes degassing processes [2] [3]. This latent energy converts into totally different types of chemical, electromagnetic and thermal energies of active compounds that are responsible for the major endogenic terrestrial processes. The dominating theories in seismology and volcanology are that an earthquake results from a sudden slip of a tectonic fault and that only magma and the gases contained in magma supply the volcanic energy resulting in the conclusions that earthquakes and eruptions are unpredictable. volcanic eruption is considered herein to be a special case of the earthquake-process in which earthquake hypocenters rise to the Earth’s surface. A possible solution is proposed ([1] and herein) based on the analyses of the physicochemical processes as participants in earthquake and eruption preparations (foreshocks - major shock - aftershocks - volcanic eruptions) and on the characteristic rates of reflection of these processes on the Earth’s surface. Influences of Sun-Moon-tides and volcanic (“harmonic”) tremors are analyzed from physical-chemical point of view. The case of the 1980 eruption of Mount St. Helens and the proposed monitoring of the recommended additional data provides a way of selecting a complex of reliable earthquake and volcanic eruption precursors.

关键词： Earthquakes volcanic Eruptions Energy Sources Physical Chemistry Precursors Electromagnetic Field Monitoring

Testing and modelling of transient adhesion phenomena in rolling-sliding contacts

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Friction 2024年第5期12卷 1016-1027页

作者： Daniel KVARDA alexander MEIERHOFER Klaus SIX Faculty of Mechanical Engineering Brno University of TechnologyBrno61669Czech Republic Virtual Vehicle Research GmbH Graz8010Austria

Transient adhesion effects in rolling–sliding contacts influence all aspects of train–track *** is of high importance specifically when these effects result in critically low adhesion,which poses a risk to traction and braking of railway *** study presents a model that can replicate the transient changes of the coefficient of adhesion with tested water and solid particle *** experimental data for the model are measured using a commercial ball-on-disc *** experimental results showed a liquid reservoir in front of the contact area that slowly reduces in *** observation was used in the modelling approach to divide the calculation into two stages where the reservoir is present and when it *** model was able to reproduce the occurrence of low adhesion region seen in experimental results with different particle concentrations.

关键词： coefficient of adhesion tribology transient effects wheel-rail contact

Graph-based structural joint pose estimation in non-line-of-sight conditions

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Earthquake Engineering and Engineering Vibration 2023年第2期22卷 371-386页

作者： alexander Thoms Zaid Al-Sabbag Sriram Narasimhan Department of Mechanical and Aerospace Engineering University of California-Los AngelesUSA Department of Civil and Environmental Engineering University of WaterlooCanada Department of Civil and Environmental Engineering University of California-Los AngelesUSA

In post-earthquake surveys,it is difficult(and often infeasible)to observe and quantify displacements beyond line-of-sight(LOS),given seismic force-resisting and gravity systems exist completely or partially within a building′s *** overcome this limitation,we develop a novel framework that generalizes graph-based state estimation towards structural joint localization via engineered *** landmarks provide an indirect means to estimate residual displacements where direct LOS is *** our framework,engineered landmarks define topologies of uniquely identifiable landmarks that are either visible or non-visible to a robot performing simultaneous localization and mapping(SLAM).Within the SLAM approach,factors encoding robot odometry and robot-to-visible landmark measurements are formulated for the cases of wireless sensing and fiducial object detection and *** landmarks are rigidly attached to non-visible landmark subsets for each engineered landmark,where the complete set of non-visible landmarks form globally rigid and localizable connectivity graphs via range-based *** subsets of non-visible landmarks are embedded within the base structure and uniquely define joint pose via geometric *** factors are unified within a common graph to solve for the maximum a posteriori estimate of robot,landmark,and joint states via nonlinear least squares *** demonstrate the applicability of our approach,we apply the Monte Carlo method over a parameterization of system noise to calculate residual joint pose error distributions,maximum average inter-story drift ratios,and related summary statistics for a 19-story nonlinear structural *** performing nonlinear time history analyses over sets of service-level and maximum considered earthquakes,our parametric study gives insight into our method′s application towards post-earthquake building evaluation in non-LOS conditions.

关键词： state estimation engineered landmarks post-earthquake residual displacement

Resource and waste quantification scenarios for wind turbine decommissioning in the United Kingdom

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Waste Disposal and Sustainable Energy 2021年第2期3卷 117-144页

作者： Kiran Tota‑Maharaj alexander McMahon Department of Civil Engineering Aston Infrastructure and Sustainable Engineering SchoolCollege of Engineering and Physical SciencesAston University BirminghamAston TriangleBirmingham B47ETUK AECOM Bristol BS16NAUK

Wind power produces more electricity than any other form of renewable energy in the United Kingdom(UK)and plays a key role in decarbonisation of the *** wind energy is seen as a sustainable alternative to fossil fuels,there are still several environmental impacts associated with all stages of the lifecycle of a wind *** study determined the material composition for wind turbines for various sizes and designs and the prevalence of such turbines over time,to accurately quantify waste generation following wind turbine decommissioning in the *** end of life stage is becoming increasingly important as a rapid rise in installation rates suggests an equally rapid rise in decommissioning rates can be expected as wind turbines reach the end of their 20-25-year operational *** data analytics were applied in this study for the UK in 5-year intervals,stemming from 2000 to *** practices for end of life waste management procedures have been analysed to create baseline *** scenarios have been used to explore potential waste management mitigation options for various materials and components such as reuse,remanufacture,recycling,and heat recovery from *** scenarios were then developed based on these waste management options,which have demonstrated the significant environmental benefits of such practices through quantification of waste reduction and greenhouse gas(GHG)emissions *** the 2015-2019 time period,over 35 kilotonnes of waste are expected to be generated *** waste is expected to increase over time to more than 1200 kilotonnes annually by *** is expected to account for the majority of waste associated with wind turbine decommissioning initially due to foundations for onshore turbines accounting for approximately 80%of their total *** 2035-2039,steel waste is expected to account for almost 50%of overall waste due to the emergence of offshore turbines,the foundations of which ar

关键词： Wind power Energy infrastructure Waste management Turbine decommissioning Life cycle Greenhouse gas emissions(GHG)

Fluency in English : an integrated course for advanced students /

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Cutting path-dependent machinability of SiCp/Al composite under multi-step ultra-precision diamond cutting

丛书名： 198 p. :

1000年

作者： alexander L. G.

来源：畅想之星图书光盘版（南... 评论

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Chinese Journal of Aeronautics 2021年第4期34卷 241-252页

作者： Shijin LU Junjie ZHANG Zengqiang LI Jianguo ZHANG Xiaohui WANG alexander HARTMAIER Jianfeng XU Yongda YAN Tao SUN Center for Precision Engineering Harbin Institute of TechnologyHarbin 150001China State Key Laboratory of Digital Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China School of Mechanical Engineering University of JinanJinan 250022China Interdisciplinary Centre for Advanced Materials Simulation Ruhr-University BochumBochum 44780Germany

Particle-tool interactions,which govern the synergetic deformation of SiC particle reinforced Al matrix composites under mechanical machining,strongly depend on the geometry of particle position residing on cutting *** the present work,we investigate the influence of cutting path on the machinability of a SiCp/Al composite in multi-step ultra-precision diamond cutting by combining finite element simulations with experimental observations and *** consistent with experimentally characterized microstructures,the simulated SiCp/Al composite is considered to be composed of randomly distributed polygonally-shaped SiC particles with a volume fraction of 25 vol%.A multi-step cutting strategy with depths of cut ranging from 2 to 10 lm is adopted to achieve an ultimate depth of cut of 10 *** material parameters and extrinsic cutting conditions utilized in finite element simulations of SiCp/Al cutting are consistent with those used in corresponding *** results reveal different particle-tool interactions and failure modes of SiC particles,as well as their correlations with machining force evolution,residual stress distribution and machined surface topography.A detailed comparison between numerical simulation results and experimental data of multi-step diamond cutting of SiCp/Al composite reveals a substantial impact of the number of cutting steps on particle-tool interactions and machined surface *** findings provide guidelines for achieving high surface finish of SiCp/Al composites by ultra-precision diamond cutting.

关键词： Cutting path Diamond cutting Finite element simulation Particle-tool interaction SiCp/Al composites

Norton-Hoff model for deformation of growing solid shell of thin slab casting in funnel-shape mold

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Journal of Iron and Steel Research International 2022年第1期29卷 88-102页

作者： alexander Vakhrushev Abdellah Kharicha Menghuai Wu Andreas Ludwig Gerald Nitzl Yong Tang Gernot Hackl Josef Watzinger Christian M.G.Rodrigues Christian-Doppler Laboratory for Metallurgical Applications of Magnetohydrodynamics Montanuniversitat Leoben8700 LeobenAustria Primetals Technologies 4031 LinzAustria Chair of Simulation and Modeling of Metallurgical Processes Department of MetallurgyMontanuniversit?t Leoben8700 LeobenAustria RHI Magnesita GmbH 1120 ViennaAustria RHI Magnesita GmbH 8700 LeobenAustria

A funnel-type mold is commonly used to provide necessary clearance for the submerged entry nozzle in the thin slab casting(TSC).The partially solidified shell is subjected to the mechanical deformations,which can lead to the defects formation and,as a results,to a ***,the results of the flow simulation,performed by the finite volume method(FVM),are fed to the external package for the finite element analysis of stress and strain.A coupled model was assembled using“creeping solid”approach by blending the Norton-Hoff viscoplastic stress for the solidifying shell with the Newtonian viscous stress of the liquid *** FVM was used to combine both liquid and solid stress models within a single *** iterative procedure based on the improved both side diffusion method was introduced to treat the nonlinear relation between the viscoplastic stress and the strain *** modeled shell thickness was verified by previously published breakout measurements and the simulation *** distribution,obtained during the TSC simulation,dominantly corresponds to the viscoplastic *** numerical approach is robust and has direct industrial application.

关键词： Solid shell Viscoplastic stress Solidification Norton-Hoff model Thin slab Continuous casting Improved both side diffusion method OpenFOAM

Electromagnetic shielding effectiveness of amorphous metallic spheroidal-and flake-based magnetodielectric composites

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Journal of Materials Science & Technology 2021年第24期83卷 256-263页

作者： Kun Qian Qifan Li alexander Sokolov Chengju Yu Piotr Kulik Ogheneyunume Fitchorova Yajie Chen Chins Chinnasamy Vincent G.Harris Center for Microwave Magnetic Materials and Integrated Circuits Department of Electrical and Computer EngineeringNortheastern UniversityBostonMA02115USA KRI at Northeastern University LLC141 South Bedford StreetBurlingtonMA01803USA Rogers Innovation Center Rogers Corporation141 South Bedford StreetBurlingtonMA01803USA Carpenter Technology Corporation ReadingPA19601USA

Flexible,lightweight,conductive materials,having both high rf losses and high permeability,are extremely desirable for applications as electromagnetic(EM)*** atomized spherical FeSi-based ferromagnetic metallic particles,having a mean diameter of 14.6μm with a standard deviation of 7.3μm,were measured to have a room temperature saturation magnetic flux density of 1.49 T with a coercivity of 160 A/*** milling of the amorphous particles led to aspect ratios from 1:1(spherical)to>100:1(flake-like).Flake-like particles,suspended in paraffin,were found to not only increase the surface area of fillers enhancing the polarization mechanism but also increase the complex permeability and complex permittivity,and thus provide broadband shielding effectiveness.A loading factor of 40 vol.%of the∼15μm diameter powders provided the largestΔW_(RL=-20 dB)of 9.49 GHz(i.e.,6.55vol.%filler at a thickness of 1.6 mm.

关键词： Amorphous particle Magnetic alloy powders Microwave absorption Electromagnetic interference shielding