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A Physical Interpretation of Mass-Energy Equivalence Based on the Orthogonal Collision
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作者 Weihong Qian 《Journal of Modern Physics》 2023年第7期1067-1086,共20页
Einstein described the mass-energy equivalence as the most important result of special relativity. But more than a century after Einstein first derived the relationship between mass-energy equivalence (or mass-energy ... Einstein described the mass-energy equivalence as the most important result of special relativity. But more than a century after Einstein first derived the relationship between mass-energy equivalence (or mass-energy equation), questions left for people are how to understand that mass and energy are somehow equivalent, and how to give the dynamical process for the conversion from mass to energy (or vice versa). This paper first interprets the formula of mass-energy equivalence published by Einstein in 1905, and then gives the equivalence relationship of mass-energy transition based on the dynamics of particle orthogonal collision. As a result, the orthogonal collision of two high-energy mass particles can generate a huge mass-energy density, equivalent to the total energy of N new particles, which is a one-way dynamic process that generates new mass-energy density and new matter. This conversion of mass into energy has nothing to do with special relativity. 展开更多
关键词 mass-Energy Equivalence Orthogonal Collision physical Interpretation Dynamical Process Special Relativity
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Strength and deformation characteristics of irregular columnar jointed rock mass: A combined experimental and theoretical study 被引量:2
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作者 Xiangcheng Que Zhende Zhu +2 位作者 Yanxin He Zihao Niu Haonan Huang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第2期429-441,共13页
The irregularity of jointed network poses a challenge to the determination of field mechanical param-eters of columnar jointed rock mass(CJRM),and a reasonable prediction of deformation and strength characteristics of... The irregularity of jointed network poses a challenge to the determination of field mechanical param-eters of columnar jointed rock mass(CJRM),and a reasonable prediction of deformation and strength characteristics of CJRM is important for engineering construction.The Voronoi diagram and three-dimensional printing technology were used to make an irregular columnar jointed mold,and the irregular CJRM(ICJRM)specimens with different dip directions and dip angles were prepared.Uniaxial compression tests were performed,and the anisotropic strength and deformation characteristics of ICJRM were described.The failure modes and mechanisms were revealed in accordance with the final appearances of the ICJRM specimens.Based on the model test results,the empirical correlations for determining the field deformation and strength parameters of CJRM were derived using the dip angle and modified joint factor.The proposed empirical equations were used in the Baihetan Project,and the calculated mechanical parameters were compared with the field test results and those obtained from the tunneling quality index method.Results showed that the deformation parameters determined by the two proposed methods are all consistent with the field test results,and these two methods can also estimate the strength parameters effectively. 展开更多
关键词 Irregular columnar jointed rock mass (ICJRM) physical model test Anisotropic characteristic Empirical relations Dip angle Modified joint factor
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Physical activity, physical fitness, and body mass index in the Chinese child and adolescent populations: An update from the 2016 Physical Activity and Fitness in China The Youth Study 被引量:33
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作者 Peijie Chen 《Journal of Sport and Health Science》 SCIE 2017年第4期381-383,共3页
In this special issue of the Journal of Sport and Health Science,analyses of the most recent national prevalence estimates from the 2016 Physical Activity and Fitness in China—The Youth Study(PAFCTYS)are presented.Th... In this special issue of the Journal of Sport and Health Science,analyses of the most recent national prevalence estimates from the 2016 Physical Activity and Fitness in China—The Youth Study(PAFCTYS)are presented.These include the prevalence of moderate-to-vigorous physical activity(MVPA)。 展开更多
关键词 ACTIVITY An update from the 2016 physical Activity and Fitness in China physical activity The Youth Study and body mass index in the Chinese child and adolescent populations physical fitness
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Eco-friendly physical blowing agent mass loss of bio-based polyurethane rigid foam materials
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作者 Haozhen Wang Lin Lin Yingshu Liu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第4期782-789,共8页
Through systematical experiment design, the physical blowing agent(PBA) mass loss of bio-based polyurethane rigid foam(PURF)in the foaming process was measured and calculated in this study, and different eco-friendly ... Through systematical experiment design, the physical blowing agent(PBA) mass loss of bio-based polyurethane rigid foam(PURF)in the foaming process was measured and calculated in this study, and different eco-friendly PBA mass losses were measured quantitatively for the first time. The core of the proposed method is to add water to replace the difference, and this method has a high fault tolerance rate for different foaming forms of foams. The method was proved to be stable and reliable through the standard deviations σ1and σ2for R1(ratio of the PBA mass loss to the material total mass except the PBA) and R2(ratio of the PBA mass loss to the PBA mass in the material total mass) in parallel experiments. It can be used to measure and calculate the actual PBA mass loss in the foaming process of both bio-based and petroleumbased PURF. The results show that the PBA mass loss in PURF with different PBA systems is controlled by its initial mass content of PBA in PU materials ω. The main way for PBA to dissipate into the air is evaporation/escape along the upper surface of foam. This study further reveals the mechanism of PBA mass loss: the evaporation/escape of PBA along the upper surface of foam is a typical diffusion behavior. Its spread power comes from the difference between the chemical potential of PBA in the interface layer and that in the outside air. For a certain PURF system, R1has approximately linear relationship with the initial mass content of PBA in PU materials ω, which can be expressed by the functional relationship R1= kω, where k is a variable related to PBA’s own attributes. 展开更多
关键词 POLYURETHANE bio-based polyol eco-friendly physical blowing agent mass loss
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Mass-Oscillators as Information Memories of Action
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作者 Hans Joachim Dudek 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2023年第1期33-50,共18页
In the theory of physical information, the physical phenomena of electromagnetism, quantum mechanics and gravity can be described by means of the action as information enclosed in four dimensional structures with osci... In the theory of physical information, the physical phenomena of electromagnetism, quantum mechanics and gravity can be described by means of the action as information enclosed in four dimensional structures with oscillator properties, under the conditions of the Hamilton principle. The present report shows that it is also possible to simulate the behaviour of the mass under these conditions. As a result, among other things, the statements are obtained that the mass is stored virtual action;the rest frame of elementary objects and the inertia of matter are caused by the action stored in the mass oscillators. 展开更多
关键词 physical Information mass Oscillators Action Higgs Mechanism
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Unity Formulas for the Coupling Constants and the Dimensionless Physical Constants
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作者 Stergios Pellis 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2023年第1期245-294,共50页
In this paper in an elegant way will be presented the unity formulas for the coupling constants and the dimensionless physical constants. We reached the conclusion of the simple unification of the fundamental interact... In this paper in an elegant way will be presented the unity formulas for the coupling constants and the dimensionless physical constants. We reached the conclusion of the simple unification of the fundamental interactions. We will find the formulas for the Gravitational constant. It will be presented that the gravitational fine-structure constant is a simple analogy between atomic physics and cosmology. We will find the expression that connects the gravitational fine-structure constant with the four coupling constants. Perhaps the gravitational fine-structure constant is the coupling constant for the fifth force. Also will be presented the simple unification of atomic physics and cosmology. We will find the formulas for the cosmological constant and we will propose a possible solution for the cosmological parameters. Perhaps the shape of the universe is Poincare dodecahedral space. This article will be followed by the energy wave theory and the fractal space-time theory. 展开更多
关键词 Fine-Structure Constant Proton To Electron mass Ratio Dimensionless physical Constants Coupling Constant Gravitational Constant Avogadro’s Number Fundamental Interactions Gravitational Fine-Structure Constant Cosmological Constant
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Mathematical Wave Functions and 3D Finite Element Modelling of the Electron and Positron
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1134-1162,共29页
The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric an... The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric and Magnetic fields. Also, every moving particle has a De Broglie wavelength determined by its mass and velocity. This paper shows that all of these properties of a particle can be derived from a single wave function equation for that particle. Wave functions for the Electron and the Positron are presented and principles are provided that can be used to calculate the wave functions of all the fundamental particles in Physics. Fundamental particles such as electrons and positrons are considered to be point particles in the Standard Model of Physics and are not considered to have a structure. This paper demonstrates that they do indeed have structure and that this structure extends into the space around the particle’s center (in fact, they have infinite extent), but with rapidly diminishing energy density with the distance from that center. The particles are formed from Electromagnetic standing waves, which are stable solutions to the Schrödinger and Classical wave equations. This stable structure therefore accounts for both the wave and particle nature of these particles. In fact, all of their properties such as mass, spin and electric charge, can be accounted for from this structure. These particle properties appear to originate from a single point at the center of the wave function structure, in the same sort of way that the Shell theorem of gravity causes the gravity of a body to appear to all originate from a central point. This paper represents the first two fully characterized fundamental particles, with a complete description of their structure and properties, built up from the underlying Electromagnetic waves that comprise these and all fundamental particles. 展开更多
关键词 ELECTRon POSITRon Wave Function Solution Electromagnetic Spin mass Charge Proof Fundamental Particle Properties Quantum Mechanics Classical Physics Computer 3D Model Schrödinger Equation RMS KLEIN GORDon Electric Magnetic Lorentz Invariant Hertzian Vector Point Potential Field Density Phase Flow Attraction REPULSIon Shell Theorem Ehrenfest VIRIAL Normalization Harmonic Oscillator
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The Intrinsic Electron with Its Properties Such as Inner Structure and Self-Mass Is in Conflict with Quantum Field Theory
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作者 Victor Vaguine 《Journal of High Energy Physics, Gravitation and Cosmology》 2023年第3期583-595,共13页
The quantum field theory (QFT) is one of branches of the Standard Model. According to QFT, quantum fields are the primary entities and particles are the excitations of these fields, coming in discrete lumps with no in... The quantum field theory (QFT) is one of branches of the Standard Model. According to QFT, quantum fields are the primary entities and particles are the excitations of these fields, coming in discrete lumps with no inner structures and with properties assigned by declaration. Such view is in conflict with the observed vacuum energy density, 140 orders of magnitudes less than required by the QFT. In addition, such view is challenged by Aphysical Quantum Mechanics (AQM), a deeper quantum theory. According to AQM, the fundamental understanding of quantum reality is expanded by the addition of two fundamental categories, aphysical and elementary consciousness of elementary particles. Based on AQM and as an example, the total ontology of the intrinsic (fundamental) electron is presented with its inner structure of perfect geometry consisting of the physical charged c-ring and aphysical cylinder, and with its properties such as self-mass, spin, magneto-electrostatic field configuration and magnetic moment. The position parameter in the inner structure demonstrates that there are no two identical intrinsic electrons in the Universe thus placing a question mark over the QFT principle of indistinguishability. 展开更多
关键词 Quantum Reality physical-Aphysical Intrinsic Electron Charged C-Ring Aphysical Cylinder Elementary Consciousness Position Parameter Constant U ontology Self-mass Indistinguishable Inner Structure
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Progress in Chinese research on water masses and circulation in the Arctic and subarctic ocean 被引量:2
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作者 CAO Yong ZHAO Jinping SHAO Qiuli 《Advances in Polar Science》 2017年第2期91-99,共9页
The Arctic Ocean and Arctic sea ice have undergone a series of rapid changes. Oceanographic surveying has become one of the key missions of the Chinese National Arctic Research Expeditions since 1999. Using the data o... The Arctic Ocean and Arctic sea ice have undergone a series of rapid changes. Oceanographic surveying has become one of the key missions of the Chinese National Arctic Research Expeditions since 1999. Using the data obtained in these surveys and from other sources, Chinese researchers have carried out a series of studies in the field of Arctic physical oceanography. The Near Sea-surface Temperature Maximum, freshwater content and heat flux in different regions of the Arctic have drawn wide attention from Chinese researchers. Arctic circulation is changing with the decline of sea ice, which is also influencing the structure and distribution of water masses. Studies have also focused on these issues. In this paper, the main results of research on water masses, currents, the structure of the upper ocean and other major hydrological phenomena over the past two decades are summarized. 展开更多
关键词 Arctic Ocean physical oceanography upper ocean water mass CURRENT
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Body Mass Index and Health Related Physical Fitness in Saudi Girls and Adolescents Aged 8 - 15 Years 被引量:3
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作者 Zahra A. Al-Asiri Afaf A. M. Shaheen 《Open Journal of Therapy and Rehabilitation》 2015年第4期116-125,共10页
Health related physical fitness (HRPF) is considered to be an indirect marker of a person’s health and wellbeing, reflecting the interplay and integration of many persons’ systems and body functions. Purpose: To inv... Health related physical fitness (HRPF) is considered to be an indirect marker of a person’s health and wellbeing, reflecting the interplay and integration of many persons’ systems and body functions. Purpose: To investigate the relationship between body mass index (BMI) and HRPF in a national cross-sectional sample of Saudi girls and adolescents. Methods: Weight, height and four components of HRPF (body fat composition, strength and endurance, flexibility and cardio-respiratory fitness) were measured in three age groups [(8 - 10), (11 - 12) and (13 - 15) years]. Pearson correlation coefficient and regressions analysis using a non-linear quadratic model were used to evaluate the relationship between BMI and HRPF in three age groups. Results: The results revealed variable relationships among tests. Lower scores in body fat composition and cardio-respiratory fitness were associated with higher body mass indexes in each age group. Also lower scores in muscle strength and endurance were recorded in girls aged from 11 to 15 years. Relationships between BMI and flexibility differed among age groups. Conclusion: BMI significantly and differentially influenced individual HRPF, but effects varied with age. Higher body mass indexes were generally associated with lower HRPF. The level of HRPF determined by this study may serve as an indicator of potential health risks that overweight and obese children girls and adolescents faced. 展开更多
关键词 BODY mass Index SAUDI Children GIRLS and Adolescents HEALTH-RELATED physical FITNESS
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Physical modeling of failure process of the excavation in horizontal strata based on IR thermography 被引量:24
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作者 HE Man-chao GONG Wei-li +1 位作者 LI De-jian ZHAI Hui-ming 《Mining Science and Technology》 EI CAS 2009年第6期689-698,共10页
In order to capture the mechanism of roadway instability in deep mines, a new approach of Physically Finite Elemental Slab Assemblage (PFESA) is proposed in order to construct a large-scale physical model simulating t... In order to capture the mechanism of roadway instability in deep mines, a new approach of Physically Finite Elemental Slab Assemblage (PFESA) is proposed in order to construct a large-scale physical model simulating the geologically horizontal strata. We carried out physical modeling on the deformation and failure processes of roadways subjected to a plane loading scheme. Our laboratory tests were based on work which incorporated infrared (IR) detection, IR radiation temperature (IRT) statistics, image feature extraction and 2D Fourier transformation, from resulting thermographies. The IRT characterizes the mechanical responses from the roadway after loading with two stages, i.e., IRT evolving at higher levels corresponded to shallow mining (≤500 m) during which the roadway deformed gradually (referred to as the "steady deformation stage"); IRT evolving in a quasi-cyclical manner with multiple peaks corresponded to deep mining (800–2600 m), in which the failure mode for the roadway are dominated by breakage and collapse (called the "unsteady deformation stage"). The IR images and 2D Fourier spectra illustrate detailed information in terms of initiation, nucleation and coalescence of the damage to rock masses and the eventual failure of roadways subject to external loading. 展开更多
关键词 红外热成像 模拟地层 物理模拟 二维傅里叶变换 项目反应理论 图像特征提取 巷道变形 发掘
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Hidden Mass Boson 被引量:1
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作者 Ivanov Mikhail Jakovlevich Mamaev Vadim Konstantinovich 《Journal of Modern Physics》 2012年第8期686-693,共8页
The evidences of the hidden mass boson existence are presented following the fruitful ideas of M. Planck and A. Einstein and using empirical data of modern physics. Within this article main parameters of this mass par... The evidences of the hidden mass boson existence are presented following the fruitful ideas of M. Planck and A. Einstein and using empirical data of modern physics. Within this article main parameters of this mass particle are predicted and its possible structure is analyzed. Moreover, the close system of nonlinear conservative equations and the spread system of Maxwell linear equations are written in the frame of phenomenological description of the hidden mass continuous medium. The displacement current, the Umov-Pointing vector and the physical vacuum polarization have been described adequately in our paper. We discuss some applications of our methodology for simulations of nature and technical device processes. In particular, numerical solutions for cosmic jets and air breathing engines are shown. 展开更多
关键词 VACUUM Mathematical Physics Hidden mass BOSon Electromagnetic Equations Conservation LAWS VACUUM Polarization Displacement Currents COSMIC Jets Air BREATHING Engines
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Physical activity, obesity and gastroesophageal reflux disease in the general population 被引量:8
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作者 Therese Djrv Anna Wikman +3 位作者 Helena Nordenstedt Asif Johar Jesper Lagergren Pernilla Lagergren 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第28期3710-3714,共5页
AIM: To clarify the association between physical activity and gastroesophageal reflux disease (GERD) in nonobese and obese people. METHODS: A Swedish population-based cross-sectional survey was conducted. Participants... AIM: To clarify the association between physical activity and gastroesophageal reflux disease (GERD) in nonobese and obese people. METHODS: A Swedish population-based cross-sectional survey was conducted. Participants aged 40-79 years were randomly selected from the Swedish Registry of the Total Population. Data on physical activity, GERD, body mass index (BMI) and the covariates age, gender, comorbidity, education, sleeping problems, and tobacco smoking were obtained using validated questionnaires. GERD was self-reported and defined as heartburn or regurgitation at least once weekly, and having at least moderate problems from such symptoms. Frequency of physical activity was categorized into three groups: (1) "high" (several times/week); (2) "intermediate" (approximately once weekly); and (3) "low" (1-3 times/mo or less). Analyses were stratified for participants with "normal weight" (BMI < 25 kg/m 2 ), "overweight" (BMI 25 to ≤ 30 kg/m 2 ) and "obese" (BMI > 30 kg/m 2 ). Multivariate logistic regression was used to calculate odds ratios (ORs) with 95% confidence intervals (CIs), adjusted for potential confounding by covariates. RESULTS: Of 6969 eligible and randomly selected individuals, 4910 (70.5%) participated. High frequency of physical activity was reported by 2463 (50%) participants, GERD was identified in 472 (10%) participants, and obesity was found in 680 (14%). There were 226 (5%) individuals with missing information about BMI. Normal weight, overweight and obese participants were similar regarding distribution of gender and tobacco smoking status, while obese participants were on average slightly older, had fewer years of education, more comorbidity, slightly more sleeping problems, lower frequency of physical activity, and higher occurrence of GERD. Among the 2146 normal-weight participants, crude point estimates indicated a decreased risk of GERD among individuals with high frequency of physical activity (OR: 0.59, 95% CI: 0.39-0.89), compared to low frequency of physical activity. However, after adjustment for potential confounding factors, neither intermediate (OR: 1.30, 95% CI: 0.75-2.26) nor high (OR: 0.99, 95% CI: 0.62-1.60) frequency of physical activity was followed by decreased risk of GERD. Sleeping problems and high comorbidity were identified as potential confounders. Among the 1859 overweight participants, crude point estimates indicated no increased or decreased risk of GERD among individuals with intermediate or high frequency of physical activity, compared to low frequency. After adjustment for confounding, neither intermediate (OR: 0.75, 95% CI: 0.46-1.22) nor high frequency of physical activity were followed by increased or decreased risk of GERD compared to low frequency among nonobese participants. Sleeping problems and high comorbidity were identified as potential confounders for overweight participants. In obese individuals, crude ORs were similar to the adjusted ORs and no particular confounding factors were identified. Intermediate frequency of physical activity was associated with a decreased occurrence of GERD compared to low frequency of physical activity (adjusted OR: 0.41, 95% CI: 0.22-0.77). CONCLUSION: Intermediate frequency of physical activity might decrease the risk of GERD among obese individuals, while no influence of physical activity on GERD was found in non-obese people. 展开更多
关键词 总人口 体力 肥胖 反流 食管 LOGISTIC回归模型 平均年龄
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The World Physical Triad: Matter, Antimatter and “Dark Energy” in the Processes of Climatic Changes on the Earth 被引量:3
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作者 Robert A. Sizov 《Journal of Modern Physics》 2016年第6期558-572,共15页
The opening and many years of research of magnetic spinor particles (real magnetic charges) in atoms and substance have enabled the author to formulate the conception of the Physical Triad, according which the real Wo... The opening and many years of research of magnetic spinor particles (real magnetic charges) in atoms and substance have enabled the author to formulate the conception of the Physical Triad, according which the real World consists of three fundamental phases: Matter, Antimatter and Energo-phase (Energo-medium). Particles of Matter are called spinors and particles of Antimatter are called antispinors. Energo-medium is a gasiform phase of high density that fills by himself all the infinite space of the real World. It consists of spinless and massless particles-energions. Spinor fields can be both flows energions (fields of Matter), so and anti-flow energions (fields of Antimatter). Atomic-shaped structures consisting of electric and magnetic spinor particles represent a Physical Mass (atoms, nucleons, etc.). The main characteristic of all varieties of Mass is its ability radiate gravitational field, which is a vortex electromagnetic field. All spinor particles are massless so as individually generate a gravitational field they can’t. All primary forces in the real World are implemented by means of Energo-medium, i.e. contact pressure its particles—energions. The spinor fields, including the gravitational field, myself the real of the power significance, have not. They are only intermediaries, inducing in Energo-medium its active (power) education, which is called “Dark Energy”. “Dark Energy” can be both positive, so and negative. Namely, a positive “Dark Energy”, which is associated with the technical activity of man, is responsible for stable climatic changes on Earth. Greenhouse gases are not the main “culprit” of climatic changes on our planet. However, these gases are the simplest indicator of the overall level of irreversible physical processes that stimulate the growth of the positive “Dark Energy” and are responsible for the negative thermal scenario on Earth. 展开更多
关键词 Magnetic and Electric Spinorial Particles (Spinors and Antispinors) Antielectrons Magnetons Antimagnetons Bispinor physical mass Vortex Electromagnetic (Gravitational) Field MATTER ANTIMATTER Energo-Medium Energions “Dark Energy” Climatic Changes
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Body Composition, Dietary Intake and Physical Activity Level of Sedentary Adult Indian Women
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作者 Gurpreet Kaur Kiran Bains Harpreet Kaur 《Food and Nutrition Sciences》 2012年第11期1577-1585,共9页
Age related changes in body composition are associated with long term dietary intake profiles. Age related increase in body fat is primarily attributed to decline in physical activity and basal metabolic rate as well ... Age related changes in body composition are associated with long term dietary intake profiles. Age related increase in body fat is primarily attributed to decline in physical activity and basal metabolic rate as well as dietary intake. The study was designed to assess the body composition, dietary intake and physical activity level of sedentary adult women of different age groups. A cross-sectional study was conducted on 152 sedentary adult women comprised of students and faculty from Punjab Agricultural University, Ludhiana. The relationship of body composition with dietary factors and physical activity level of women in four age groups i.e. 21 - 30, 31 - 40, 41 - 50 and 51 - 60 years was determined. A gradual increase (p ≤ 0.05) in anthropometric and body composition parameters such as weight, waist circumference, hip circumference, body mass index, fat mass and visceral fat rating was observed with the advancement of age. The lean body mass was decreased significantly (p ≤ 0.05) as the age progressed, the values for four age groups being 74.9, 68.9, 62.8 and 60.9%, respectively. Contrary to this fat mass increased with age, the corresponding values for four age groups being 15.7, 21.4, 26.6 and 29.2 kg, respectively. The percent adequacy of protein by four age groups was 69.6, 78.2, 80.0 and 66.3, respectively when compared to RDA while fat intake was much higher i.e. 245.5, 271.8, 288.4 and 250.8%, respectively. The energy intake was inadequate among all age groups, however, a significant (p ≤ 0.05) differ- ence was observed in daily energy consumption between the age groups. The mean physical activity level (PAL) of the subjects ranged between 1.49 - 1.60. The physical activity level values showed that majority of the subjects (87% - 94%) were having sedentary life style. Age is a crucial factor associated with body composition. A high fat mass and low lean body mass of the subjects was observed. Their diets were low in protein but high in fat. Majority of the subjects from different age groups had sedentary life style. A diet with higher protein and lesser fat combined with exercise can help in sustaining optimum body composition. 展开更多
关键词 LEAN Body mass FAT mass DIETARY Factors physical Activity Level
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Mass Modeling of Sweet Cherry (<i>Prunus avium</i>L.) Fruit with Some Physical Characteristics
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作者 Feizollah Shahbazi Satar Rahmati 《Food and Nutrition Sciences》 2013年第1期1-5,共5页
Horticultural crops with the similar weight and uniform shape are in high demand in terms of marketing value that used as food. The knowledge on existing relationship among the mass, length, width, thickness, volume a... Horticultural crops with the similar weight and uniform shape are in high demand in terms of marketing value that used as food. The knowledge on existing relationship among the mass, length, width, thickness, volume and projected areas of fruits is useful for proper design of grading machines. A part of this research was aimed to present some physical properties of cherry fruit. In addition, in this study the mass of cherry fruit was predicted with using different physical characteristics in four models including: Linear, Quadratic, S-curve, and Power. According to the results, all properties considered in the current study were found to be statistically significant at the 1% probability level. The best and the worst models for mass prediction of cherry fruit were based on geometric mean diameter and thickness of the cherry with determination coefficients (R2) of 0.938 and 0.484, respectively. At last, mass model of cherry fruit based on first projected area from economical standpoint is recommended. 展开更多
关键词 SWEET CHERRY physical Characteristics mass Prediction
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Comparison of the Two Algorithms of Skeletal Muscle Mass Index: An Observational Study in a Large Cohort of Chinese Adults
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作者 Ying Sui Zhen Huang +1 位作者 Shengyong Dong Yansong Zheng 《Health》 CAS 2022年第8期895-909,共15页
Objective: To compare the two skeletal muscle mass index (SMI) algorithms. One is SMM [SMM(%) = total skeletal muscle mass (kg)/body weight mass (kg) × 100%];and the other is SMH [SMH (kg/m<sup>2</sup>... Objective: To compare the two skeletal muscle mass index (SMI) algorithms. One is SMM [SMM(%) = total skeletal muscle mass (kg)/body weight mass (kg) × 100%];and the other is SMH [SMH (kg/m<sup>2</sup>) = total skeletal muscle mass (kg)/height (m)<sup>2</sup>]. Methods: Body composition, body mass index (BMI) and body fat percentage (BFP) were estimated using a bioelectrical impedance analyzer. SMI was calculated by the two algorithms described above, and measurement parameters were stratified by age, BMI and levels of physical activity. Results: Levels of BMI, BFP, SMM and SMH differed significantly between the sexes. BMI and BFP were positively associated with age, while SMM was negatively associated with age (β = &minus;0.2294, P < 0.001). Furthermore, SMM was determined to have a negative association with BMI (β = &minus;0.5340, P < 0.001), while a positive association between SMH and BMI (β = 0.7930, P β = &minus;0.9849, P β = &minus;0.0642, P < 0.001) were negatively associated with BFP. In both men and women, SMM maintained the analogous correlation with other indicators. In the general population, SMM showed a gradual downward trend from low body weight to grade III obesity (F = 9528.32, P < 0.001), but SMH (F = 34395.46, P F = 9706.20, P < 0.001) had a reciprocal association. BMI, BFP and SMM differences were observed based on levels of physical activity (P < 0.001). However, there was no significant difference in SMH based on exercise (P > 0.05). Conclusions: SMM may be a more ideal and accurate clinical algorithm for SMI because it is more tightly associated with other body composition indices, as compared with SMH. 展开更多
关键词 physical Examination Body Weight Muscle mass Skeletal Muscle mass Index
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Completing the Standard Model with Gravity by General Relativizing Quantum Physics (RQP) (Coupling Spin-2 Gravitons with Spin-0 Particles to Generate Higgs Mass)
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作者 Walter James Christensen Jr. 《Journal of Modern Physics》 2015年第13期1969-1985,共17页
After a straightforward general relativistic calculation on a modified flat-spacetime metric (developed from the fluctuating vacuum energy interacting with a graviton field), a pair of n-valued covariant and contravar... After a straightforward general relativistic calculation on a modified flat-spacetime metric (developed from the fluctuating vacuum energy interacting with a graviton field), a pair of n-valued covariant and contravariant energy momentum tensors emerged analogous to quantized raising and lower operators. Detaching these operators from the general relativistic field equations, and then transporting them to act on extreme spacetimes, these operators were able to generate fundamental particle boson masses. In particular, the operators precisely generated Higgs mass. Then by applying a consistency approach to the gravitational field equations—similar to how Maxwell applied to the electromagnetic ones—it allowed for the coupling of spin-to-mass, further restricting the particle mass to be in precise agreement with CODATA experimental values. Since this is a massless field approach integrated discretely with a massive one, it overcomes various renormalizing difficulties;moreover it solves the mass hierarchal problem of the Standard Model of particle physics, and generates its spin and therefore shows quantum physics to be a subset of General Relativity, just as Einstein had first imagined. 展开更多
关键词 Standard Model Particle PHYSICS GENERAL Relativity Geometric PARTICLES Higgs mass Relativized Quantum PHYSICS RQP Graviton Gravitational Lagrangian Consistency Formulation for GRAVITY mass Hierarchal Problem
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A Phenomenological Model for the Electromagnetic Origin of Mass in Particles, and Its Quantitative Application to the Electron, the Muon, the Proton, and the Neutron
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作者 Osvaldo F. Schilling 《Journal of Modern Physics》 2013年第9期1189-1193,共5页
A simple phenomenological model is developed, which indicates the existence of a direct link between the concept of rest mass of a particle and magnetodynamic energies associated to the formation of the particle. The ... A simple phenomenological model is developed, which indicates the existence of a direct link between the concept of rest mass of a particle and magnetodynamic energies associated to the formation of the particle. The model is based upon the principles of quantization and conservation of flux, well known for their application in superconductivity. The charge of particles is considered as forming vortices of superconducting currents, which we postulate are created by electromagnetic fluctuations from vacuum (or related processes). A new quantization rule gathers the size, the magnetic moment, and the rest mass of the particle and associates these quantities to the integer number of flux quanta that should be stored in the vortices corresponding to each particle. The model is applied to the electron, the muon, the proton, and the neutron. Quantitative consistency with available experimental data for these subatomic particles is obtained. 展开更多
关键词 mass PARTICLE Physics PARTICLES Models PARTICLE RADIUS Flux Quantization
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A Classical Explanation for Relativistic Longitudinal and Transverse Mass Increase
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2021年第8期1904-1910,共7页
In this paper, I show that the Special Relativistic effect of mass increase that occurs within objects when they move at high speed can be explained using Classical Physics principles. In my analysis, the wave nature ... In this paper, I show that the Special Relativistic effect of mass increase that occurs within objects when they move at high speed can be explained using Classical Physics principles. In my analysis, the wave nature of condensed matter and energy/mass equivalence are taken into consideration. The wave nature of particles is modelled as the particle structure comprising three-dimensional standing waves. When this is done, the difference in the energy sum of the component waves that comprise a particle moving at a high speed, when compared to those of a stationary particle, completely accounts for the mass increase. Furthermore, the additional momentum of the wave components in the direction of motion (the Longitudinal direction) is the cause of the inertia, or effective mass, of the object being greater than that in the Transverse direction (orthogonal to the direction of motion). 展开更多
关键词 Special RELATIVITY CLASSICAL Physics RELATIVISTIC mass Longitudinal Transverse Inertia Component INCREASE Standing Wave Equivalence Condensed Matter
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