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Error field penetration in j.TEXT tokamak based on two-fluid drift-MHD model

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Chinese Physics B 2024年第4期33卷 545-551页

作者：王文徐涛张仪 the j.TEXT team State Key Laboratory of Advanced Electromagnetic Technology International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma PhysicsSchool of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China

An externally generated resonant magnetic perturbation can induce complex non-ideal MHD responses in their resonant *** have studied the plasma responses using Fitz.atrick's improved two-fluid model and program *** calculated the error field penetration threshold for *** addition,we find that the island width increases slightly as the error field amplitude increases when the error field amplitude is below the critical penetration ***,the island width suddenly j.mps to a large value because the shielding effect of the plasma against the error field disappears after the *** scanning the natural mode frequency,we find that the shielding effect of the plasma decreases as the natural mode frequency ***,we obtain the m/n=2/1 penetration threshold scaling on density and temperature.

关键词： plasma responses drift-MHD model error field penetration

Evaluating the Effects of Graviton Redshift upon Spiral Galaxy Rotation Curves, Surface Brightness Magnitudes and Gravitational Lensing

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j.urnal of High Energy Physics, Gravitation and Cosmology 2024年第3期10卷 967-985页

作者： Firmin j. Oliveira East Asian Observatory James Clerk Maxwell Submillimetre Telescope Hilo USA

The effects of the gravitational redshift of gravitons upon spiral galaxy rotation energy are compared to the standard mass to light analyses in obtaining rotation curves. The derivation of the total baryonic matter compares well with the standard theory and the rotation velocity is matched to a high precision. The stellar mass distributions obtained from the fit with graviton energy loss are used to derive the surface brightness magnitudes for the galaxies, which agree well with the observed measurements. In a new field of investigation, the graviton theory is applied to the observations of gravitational lenses. The results of these applications of the theory suggest that it can augment the standard methods and may eliminate the need for dark matter.

关键词： Gravitons Gravitational Redshift Surface Brightness Gravitational Lens Lens Mass

The Regional Economic Impacts of Coal Mining: A Case Study of Signal Peak Energy

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Natural Resources 2024年第8期15卷 211-223页

作者： Timothy j. Considine School of Energy Resources University of Wyoming Laramie USA

This paper quantifies the regional economic contributions of coal exports from the US using a case study of Signal Peak Energy in Montana. Two methods of estimating economic contributions are compared, contribution and impact analysis. The latter is adopted because the industry impact analysis is more accurate, especially since it is based upon accounting records from Signal Peak. Our estimates of regional economic and fiscal impacts do not vary significantly with the price of coal because we explicitly account for swings in royalty income. Our analysis finds that Signal Peak Energy supports 678 j.bs, over $55 million in tax revenues, more than $90 million in royalties, $111.7 million in value added, and $62.3 million in labor income. Curtailing or halting Signal Peak’s coal production for environmental reasons as some environmental groups have argued would eliminate these economic contributions.

关键词： Coal Regional Economic Exports Fiscal

Development of Multilayer Models of Globular Star Clusters and Study of Their Evolution

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j.urnal of Modern Physics 2024年第8期15卷 1246-1299页

作者： j.seph j. Smulsky Institute of Earths Cryosphere Tyum. SC of SB RAS Federal Research Center Tyumen Russia

Usually, models of globular star clusters are created by analyz.ng their luminosity and other observation parameters. The goal of this work is to create stable models of globular clusters based on the laws of mechanics. It is necessary to set the coordinates, velocities and masses of the stars so that as a result of their gravitational interaction the globular cluster is not destroyed. This is not an easy task, and it has been solved in this paper. Using an exact solution of the axisymmetric gravitational interaction of N-bodies, single-layer spherical structures were created. They are combined into multilayer models of globular clusters. An algorithm and a program for their creation is described. As a result of solving the problem of gravitational interaction of N bodies, evolution of 5-, 10-, and 15-layer structures was studied. During the inter-body interaction, there proceeds a transition from the initial specially organiz.d structure to a structure with bodies, uniformly distributed in space. The number of inter-body collisions decreases, and the globular cluster model passes into the stable form of its existence. The collisions of bodies and the acquisition of rotational motion and thermal energy by them are considered. As a result of the passage to scaled dimensions, the results were recalculated to the conditions of globular star clusters. The periods of rotation and the temperatures of merged stars are calculated. Attention is paid to a decreased central-body mass in the analyz.d models of globular star clusters.

关键词： N-Body Problem Solution Globular Star Clusters Properties

Fresnel Equations Derived Using a Non-Local Hidden-Variable Particle Theory

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j.urnal of Modern Physics 2024年第6期15卷 950-984页

作者： Dirk j. Pons Department of Mechanical Engineering University of Canterbury Christchurch New Zealand

Problem: The Fresnel equations describe the proportions of reflected and transmitted light from a surface, and are conventionally derived from wave theory continuum mechanics. Particle-based derivations of the Fresnel equations appear not to exist. Approach: The obj.ctive of this work was to derive the basic optical laws from first principles from a particle basis. The particle model used was the Cordus theory, a type of non-local hidden-variable (NLHV) theory that predicts specific substructures to the photon and other particles. Findings: The theory explains the origin of the orthogonal electrostatic and magnetic fields, and re-derives the refraction and reflection laws including Snell’s law and critical angle, and the Fresnel equations for s and p-polarisation. These formulations are identical to those produced by electromagnetic wave theory. Contribution: The work provides a comprehensive derivation and physical explanation of the basic optical laws, which appears not to have previously been shown from a particle basis. Implications: The primary implications are for suggesting routes for the theoretical advancement of fundamental physics. The Cordus NLHV particle theory explains optical phenomena, yet it also explains other physical phenomena including some otherwise only accessible through quantum mechanics (such as the electron spin g-factor) and general relativity (including the Lorentz.and relativistic Doppler). It also provides solutions for phenomena of unknown causation, such as asymmetrical baryogenesis, unification of the interactions, and reasons for nuclide stability/instability. Consequently, the implication is that NLHV theories have the potential to represent a deeper physics that may underpin and unify quantum mechanics, general relativity, and wave theory.

关键词： Wave-Particle Duality Optical Law Fresnel Equation Non-Local Hidden-Variable

Experimental and Analytical Study of a Single Effect Distillation Using Electrical Evaporator Powered by Solar Energy

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j.urnal of Power and Energy Engineering 2024年第8期12卷 20-29页

作者： Saeed j. Almalowi Mechanical & Manufacturing Engineering Department Jubail Industrial College The Royal Commission for Jubail and Yanbu Jubail Saudi Arabia

The experimental and analytical investigation was conducted on a solar-powered single-effect distillation (SED). The evaporator was designed to be an electrical evaporator as opposed to the steam evaporator that existed previously. Using sun-tracking solar panels, the electrical evaporator in the designed distillation unit was powered by solar energy. Approximately 20 kWh was utiliz.d by the small-scale distillation apparatus. This type of design is mobile, so remote areas and countries with fragile economies can utiliz. it on a small or large scale. Utiliz.ng the principles of energy and mass conservation, the amount of distillate water and power required for a single unit was determined, at the low salinity (2200 PPM) with fixed boiling point temperature (Tb = 75˚C), the unit performance is approx. 98.4%. The experimental results and those derived from a mathematical model were compared, and both showed strong accord. Using engineering equation solver (EES) software, a computer program was developed for this research scenario.

关键词： Distillation Single Effect Solar Potable Salt

Mass-Based Environmental Factor and Energy Assessment of Microwave-Assisted Synthesiz.d Transition Metal Nanostructures

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American j.urnal of Analytical Chemistry 2024年第6期15卷 201-218页

作者： Victor j. Law School of Mechanical and Materials Engineering University College Dublin Dublin Ireland

This paper describes mass-based energy phase-space proj.ction of microwave-assisted synthesis of transition metals (z.nc oxide, palladium, silver, platinum, and gold) nanostructures. The proj.ction uses process energy budget (measured in kj. on the horiz.ntal axes and process density (measured in kj.−1) on the vertical axes. These two axes allow both mass usage efficiency (Environmental-Factor) and energy efficiency to be evaluated for a range of microwave applicator and metal synthesis. The metrics are allied to the: second, sixth and eleventh principle of the twelve principle of Green Chemistry. This analytical approach to microwave synthesis (widely considered as a useful Green Chemistry energy source) allows a quantified dynamic environmental quotient to be given to renewable plant-based biomass associated with the reduction of the metal precursors. Thus allowing a degree of quantification of claimed “eco-friendly” and “sustainable” synthesis with regard to waste production and energy usage.

关键词： Microwave-Assisted Synthesis Transition Metals Nanostructures Allometry Scaling Power-Law Signature Green Chemistry

An Analysis of Specific Categories of Birth Defects and Developmental Disabilities for Children of Participants of the Air Force Health Study

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Open j.urnal of Epidemiology 2024年第2期14卷 312-330页

作者： George j. Knafl School of Nursing University of North Carolina at Chapel Hill Chapel Hill NC USA

Background: The Air Force Health Study collected reproductive outcomes for live-born children of male Air Force veterans of the Vietnam War. Methods: Dioxin values for participants were obtained from blood samples. Analyses were conducted of occurrence of 16 specific categories of birth defects and developmental disabilities. Children were categoriz.d as conceived before and after the start of participants’ Vietnam War service. Children conceived before the start of Vietnam War service were treated as being conceived when their fathers had unquantifiable dioxin values. Children conceived after the start of Vietnam War service for participants with missing dioxin values were excluded from primary analyses, but were used to assess the impact of their exclusion on conclusions. Correlation between values for specific categories for multiple children fathered by the same participant was accounted for. The dose-response relationship was treated as a step function increasing for dioxin values larger than adaptively identified individual thresholds changing with the specific category. Results: For 15 of 16 specific categories, the probability of occurrence increased substantially for a sufficiently high dioxin level above identified thresholds. Exclusion of children due to missing dioxin likely did not affect these results. Conclusions: Results supported the conclusion of substantial adverse effects on a wide variety of specific categories of birth defects and developmental disabilities due to sufficiently high exposures to dioxin, a toxic contaminant of Agent Orange used for herbicide spraying in the Vietnam War. Results may hold more generally, but might also have been affected by a variety of limitations.

关键词： Agent Orange Air Force Health Study Birth Defects Developmental Disabilities Dioxin Dose-Response Relationship Vietnam War

Where Is Phase Velocity in Minkowski Space?

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j.urnal of Modern Physics 2024年第10期15卷 1555-1566页

作者： Antony j. Bourdillon Ultra-High Resolution Lithography San Jose CA USA

In the special theory of relativity, massive particles can travel at neither the speed of light c nor faster. Meanwhile, since the photon was quantiz.d, many have thought of it as a point particle. How pointed? The idea could be a mathematical device or physical simplification. By contrast, the preceding notion of wave-group duality has two velocities: a group velocity vg and a phase velocity vp. In light vp = vg = c;but it follows from special relativity that, in massive particles, vp > c. The phase velocity is the product of the two best measured variables, and so their product constitutes internal motion that travels, verifiably, faster than light. How does vp then appear in Minkowski space? For light, the spatio-temporal Lorentz.invariant metric is s2=c2t2−x2−y2−z., the same in whatever frame it is viewed. The space is divided into 3 parts: firstly a cone, symmetric about the vertical axis ct > 0 that represents the world line of a stationary particle while the conical surface at s = 0 represents the locus for light rays that travel at the speed of light c. Since no real thing travels faster than the speed of light c, the surface is also a horiz.n for what can be seen by an observer starting from the origin at time t = 0. Secondly, an inverted cone represents, equivalently, time past. Thirdly, outside the cones, inaccessible space. The phase velocity vp, group velocity vg and speed of light are all equal in free space, vp = vg = c, constant. By contrast, for particles, where causality is due to particle interactions having rest mass mo > 0, we have to employ the Klein-Gordon equation with s2=c2t2−x2−y2−z.+mo2c2. Now special relativity requires a complication: *** = c2 where vg c and therefore vp > c. In the volume outside the cones, causality due to light interactions cannot extend beyond the cones. However, since vp > c and even vp >> c when wavelength λ is long, extreme phase velocities are then limited in their causal effects by the particle uncertainty σ,

关键词： Event Horiz.n Scattering Range Wave Packet Phase Velocity Group Velocity Dispersion Dynamics Quantum Physics