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Total Energy Expenditure of 16 Chinese Young Men Measured by the Doubly Labeled Water Method 被引量:4
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作者 ZHUO Qin SUN Rui +5 位作者 GOU Ling Yan PIAO Jian Hua LIU Jian Min TIAN Yuan ZHANG Yu Hui YANG Xiao Guang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第6期413-420,共8页
Objective Doubly labeled water (DLW) method is the gold standard for measuring total energy expenditure (TEE). We used this method to measure TEE in Chinese young men. Methods Sixteen healthy young men age 23±... Objective Doubly labeled water (DLW) method is the gold standard for measuring total energy expenditure (TEE). We used this method to measure TEE in Chinese young men. Methods Sixteen healthy young men age 23±1 recruited. TEE was measured by the DLW method, by indirect calorimetry. We also conducted 24-h estimate energy requirements of the subjects. years with body mass index 22.0±1.4 kg/m2 were and basal energy expenditure (BEE) was determined activity, energy balance and factorial approach to Results TEE of subjects by DLW method was 9.45±0.57 M J/day (2258±180 kcal/day). The 24-h activity was 10.80±0.33 M J/day (2582±136 kcal/day). The energy requirement, derived from energy balance observations, was 9.93±1.32 M J/day (2373±315 kcal/day). The BEE of 6.65±0.28 M J/day (1589±67 kcal/day), calculated by the adjusted Schofield equation, was significantly higher (P〈O.O01) than that measured by indirect calorimetry, 5.99-±0.66 M J/day (1433-±158 kcal/day). The TEE derived from the factorial approach was 10.31-±0.43 M J/day (2463±104 kcal/day). Conclusion The TEE of Chinese young men measured by the DLW method was about 10% lower than the current recommended nutrient intake (RNI), suggesting that the RNI for Chinese men maybe overestimated. Further studies are warranted to determine the value of the estimated energy requirement. 展开更多
关键词 Doubly labeled water total energy expenditure Recommended nutrient intakes Estimatedenergy requirement Chinese young men
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RENEWAL OF BASIC LAWS AND PRINCIPLES FOR POLAR CONTINUUM THEORIES (Ⅷ)—PRINCIPLE OF TOTAL WORK AND ENERGY 被引量:2
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作者 戴天民 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第3期313-318,共6页
Theoretical incompleteness of the existing conservation laws of energy for polar continuum mechanics is further clarified. For completeness, the principles of total work and energy and of total work and energy of incr... Theoretical incompleteness of the existing conservation laws of energy for polar continuum mechanics is further clarified. For completeness, the principles of total work and energy and of total work and energy of incremental rate type are postulated. Via total variations of the former and the latter of them, the principles of virtual displacement and microrotation & stress and couple stress as well as virtual velocity and angular velocity & stress rate and couple stress rate are immediately obtained, respectively. From these principles all balance equations and boundary conditions for micropolar mechanics are naturally and simultaneously deduced. The essential differences between the nontraditional results obtained in this paper and the existing conservation laws of energy are expounded. 展开更多
关键词 micropolar continua total work and energy total virtual work and energy incremental rate type conservation law of energy
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Influencing Factors of Total Factor Energy Efficiency in Bohai Rim Region Based on DEA-Tobit Model 被引量:1
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作者 Weifeng Gong Xiaohong Qi +2 位作者 ChuanhuiWang Wenwen Li Yang Xu 《Energy Engineering》 EI 2022年第4期1663-1679,共17页
Bohai Rim region is an important economic development area and a large carbon emission area in China.It is of great significance to explore the total factor energy efficiency and its influencing factors for the low ca... Bohai Rim region is an important economic development area and a large carbon emission area in China.It is of great significance to explore the total factor energy efficiency and its influencing factors for the low carbon transformation and high-quality development of the Bohai Rim region.Based on the total factor energy efficiency framework,the DDF-DEA model was used to calculate the total factor energy efficiency,and the internal and external differences of the total factor energy efficiency were further analyzed.The internal and external influencing factors were determined by ML index method and classical endogenous growth theory,and then the Tobit panel model was used to empirically analyze the action mechanism of all influencing factors of total factor energy efficiency in the Bohai Rim region.The results show that the pure technical efficiency,scale efficiency and technological progress among the internal influencing factors contribute to the improvement of energy efficiency in the Bohai Rim region.Industrial structure,industrial internal structure and ownership structure inhibit the improvement of energy efficiency.Energy consumption structure and energy endowment also have a negative impact on energy efficiency.Therefore,measures such as promoting technological progress,adjusting economic structure and optimizing energy structure will effectively improve total factor energy efficiency in the Bohai Rim region. 展开更多
关键词 total factor energy efficiency influencing factors Bohai Rim region DEA-Tobit model ML index method
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SUPER NONLINEAR TOTAL ENERGY OF A PARTICLE AND THE THEORY OF DE BROGLIE WAVE
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作者 杨文熊 杨长俊 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1999年第5期65-69,共5页
By using Laurent series, the veloci ty (~c) is expanded and then the total energy expression of a particle moving w ith high velocity is obtained. The total energy contains two parts: the rest e ne rgy and the kineti... By using Laurent series, the veloci ty (~c) is expanded and then the total energy expression of a particle moving w ith high velocity is obtained. The total energy contains two parts: the rest e ne rgy and the kinetic energy. Also in this paper the theory of the de Broglie wave from the relation of the energy_momentum is obtained in which the phase velocit y is still less than the velocity of light c . 展开更多
关键词 super nonlinear total energy kinetic e nergy rest energy MOMENTUM de Broglie wave
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Calculations Energy of the (<i>nl</i><sup>2</sup>) <sup>1</sup><i>L<sup>π</sup></i>Doubly Excited States of Two-Electron Systems via the Screening Constant by Unit Nuclear Charge Formalism
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作者 Momar Talla Gning Ibrahima Sakho Malick Sow 《Journal of Modern Physics》 2020年第11期1891-1910,共20页
In this work, the total energies of doubly excited states (<em>ns</em><sup>2</sup>) <sup>1</sup>S<sup>e</sup>, (<em>np</em><sup>2</sup>) <sup&... In this work, the total energies of doubly excited states (<em>ns</em><sup>2</sup>) <sup>1</sup>S<sup>e</sup>, (<em>np</em><sup>2</sup>) <sup>1</sup>D<sup>e</sup>, (<em>nd</em><sup>2</sup>) <sup>1</sup>G<sup>e</sup>, (<em>nf</em><sup>2</sup>) <sup>1</sup>I<sup>e</sup>, (<em>ng</em><sup>2</sup>) <sup>1</sup>K<sup>e</sup>, and (<em>nh</em><sup>2</sup>) <sup>1</sup>M<sup>e</sup> of the helium isoelectronic sequence with Z ≤ 10 are calculated in the framework of the variational method of the Screening Constant by Unit Nuclear Charge (SCUNC). These calculations are performed using a new wavefunction correlated to Hylleraas-type. The possibility of using the SCUNC method in the investigation of high-lying Doubly Excited States(DES) in two-electron systems is demonstrated in the present work in the case of the (<em>nl</em><sup>2</sup>) <sup>1</sup><em>L</em><sup><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><em>&pi;</em></span></span></span></sup> doubly excited states, where accurate total energies are tabulated up to <em>n</em> = 20. All the results obtained in this paper are in agreement with the values of the available literature and may be useful for future experimental and theoretical studies on the doubly excited (<em>nl</em><sup>2</sup>) <sup>1</sup><em>L</em><sup><span style="white-space:nowrap;"><span style="white-space:nowrap;"><em>π</em></span></span></sup> states of two-electron systems. 展开更多
关键词 Doubly Excited States Helium-Like systems Screening Constant by Unit Nuclear Charge (SCUNC) Wave Functions Correlated total energy
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Total Energy and Electronic States of CdSe Nanoparticles
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作者 V.Zavodinsky O.Gorkusha A.Kuz’menko 《Semiconductor Science and Information Devices》 2022年第1期1-7,共7页
The authors fulfilled calculations of the total energy and electronic states of Cd_(n)Se_(n) nanoparticle:“wurzite”,“sphalerite”and“rock-salt”types of the structure.It was shown that at n≤72 the“rock-salt”typ... The authors fulfilled calculations of the total energy and electronic states of Cd_(n)Se_(n) nanoparticle:“wurzite”,“sphalerite”and“rock-salt”types of the structure.It was shown that at n≤72 the“rock-salt”type is the most favorable energetically.However the extrapolation of the behavior of the energy per Cd-Se atomic pair shows that for n>130(corresponding to a size of about 2 nm),particles with a“wurtzite”structure can be more advantageous.Particles of the“wurtzite”and“rock-salt”types have an electronic structure with an energy gap.For particles with the“wurtzite”structure,the gap width decreases with increasing particle size:from 3.3 eV to 2.2 eV as the particle increases from 0.5 nm to 1.5 nm.For particles of the“rock-salt”type,the gap width grows slightly,remaining about 3 eV.“Sphalerite”-type particles have a metal-like electronic structure. 展开更多
关键词 NANOPARTICLES Cadmium selenide total energy Energetic gap Modeling with pseudopotentials
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Life Cycle Assessment Introduced by Using Nanorefrigerant of Organic Rankine Cycle System for Waste Heat Recovery
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作者 Yuchen Yang Lin Ma +2 位作者 Jie Yu Zewen Zhao Pengfei You 《Journal of Renewable Materials》 SCIE EI 2023年第3期1153-1179,共27页
The use of nanorefrigerants in Organic Rankine Cycle(ORC)units is believed to affect the cycle environment performance,but backed with very few relevant studies.For this purpose,a life cycle assessment(LCA)has been pe... The use of nanorefrigerants in Organic Rankine Cycle(ORC)units is believed to affect the cycle environment performance,but backed with very few relevant studies.For this purpose,a life cycle assessment(LCA)has been performed for the ORC system using nanorefrigerant,the material and energy input,characteristic indicators and comprehensive index of environmental impact,total energy consumption and energy payback time(BPBT)of the whole life cycle of ORC system using Al_(2)O_(3)/R141b nanorefrigerant were calculated.Total environmental comprehensive indexes reveal that ECER-135 index decrease by 1.5%after adding 0.2%Al_(2)O_(3)nanoparticles to R141b.Based on the contribution analysis and sensitivity analysis,it can be found out ORC system manufacturing is of the most critical stage,where,the ECER-135 index of ORC component production is the greatest,followed by the preparation process of R141b,transportation phase,and that of Al_(2)O_(3)nanoparticles preparation is small.The retirement phase which has good environmental benefits affects the result significantly by recycling important materials.Meanwhile,the main cause and relevant suggestion for improvement were traced respectively.Finally,the environmental impacts of various power generations were compared,and results show that the power route is of obvious advantage.Among the renewable energy,ORC system using Al_(2)O_(3)/R141b nanorefrigerant with minimal environmental impact is only 0.67%of coal-fired power generation.The environmental impact of current work is about 14.34%of other nations’PV results. 展开更多
关键词 Life cycle assessment Organic Rankine Cycle NANOREFRIGERANT total energy consumption energy payback time
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Thermodynamic analysis and combined cycle research on recoverable pressure energy in natural gas pipeline 被引量:2
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作者 郑斌 刘俊德 《Journal of Beijing Institute of Technology》 EI CAS 2011年第1期65-70,共6页
Current research and ways of capturing mechanical energy are discussed in this paper. By the aid of the comprehensive thermodynamic analysis and Aspen simulation tool, the amount of a vailable work that can be produc... Current research and ways of capturing mechanical energy are discussed in this paper. By the aid of the comprehensive thermodynamic analysis and Aspen simulation tool, the amount of a vailable work that can be produced from capturing the pressure energy has been calculated. Based on the comprehensive thermodynamic analysis, two systems have been proposed to capture pressure energy of natural gas to generate electricity. In this study, the expression of exergy is given which can be used in evaluating purposes. A problem with this multidisciplinary study is the complicated boundary condition. In conclusion, a technical prospect on recoverable natural gas pressure energy has been presented based on total energy system theory. 展开更多
关键词 natural gas pressure energy thermodynamic analysis exergy analysis power genera-tion combined cycle total energy system
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Study on Buildings CCHP System Based on SOFC 被引量:1
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作者 Bin Zhang Yongzhen Wang +1 位作者 Jiaqing Zheng Dan Liu 《Fluid Dynamics & Materials Processing》 EI 2020年第3期665-674,共10页
The relationship among the working temperature,pressure and current density of a Solid oxide fuel cell(SOFC)and its output power and efficiency are analyzed in the framework of a theoretical model able to provide,amon... The relationship among the working temperature,pressure and current density of a Solid oxide fuel cell(SOFC)and its output power and efficiency are analyzed in the framework of a theoretical model able to provide,among other things,the volt ampere characteristic curve.In particular,following the principle of temperature matching and cascade utilization,we consider a gas turbine(GT)and a LiBr absorption chiller to recycle the high-grade exhaust heat produced by the considered SOFC.This distributed total energy system is set up with the intent to meet typical needs of buildings for cooling,heating and power(CCHP).The total power generated by the considered SOFC and gas turbine is about 222 kW and the total power generation efficiency by low heat value of fuel(LHV)is 63.7%.In the CCHP system,the high temperature exhaust of GT is further used to drive LiBr absorption unit,which can produce about 34.8 kW cooling capacity or 84.5 kW of heat(the total energy utilization 78.03%). 展开更多
关键词 SOFC gas turbine absorption chiller CCHP total energy system
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Bound State Description of Particles from a Quantum Field Theory of Fermions and Bosons, Compatible with Relativity
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作者 Hans-Peter Morsch 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期562-573,共12页
Both, the dilemma to find a quantum field theory consistent with Einstein’s law of relativity and the problem to describe existing particles as bound states of matter has been solved by calculating bound state matrix... Both, the dilemma to find a quantum field theory consistent with Einstein’s law of relativity and the problem to describe existing particles as bound states of matter has been solved by calculating bound state matrix elements from a dual fermion-boson Lagrangian. In this formalism, the fermion binding energies are compensated by boson energies, indicating that particles can be generated out of the vacuum. This yields quantitative solutions for various mesons ω (0.78 GeV) - Υ (9.46 GeV) and all leptons e, μ and τ, with uncertainties in the extracted properties of less than 1‰. For transparency, a Web-page with the address htpps://h2909473.stratoserver.net has been constructed, where all calculations can be run on line and also the underlying fortran source code can be inspected. 展开更多
关键词 Quantum Field Theory of Fermion and Boson Fields Hadrons and Leptons Described as Bound States of Relativistic Fermions and Bosons Leading to a total energy Equal to Zero
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SELF-CONSISTENT TOTAL ENERGIES AND ELECTRONIC STRUCTURES OF HYDROGENIZED Ni,Al AND Ni_3Al
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作者 XIE Qian, CHEN NanxianUniversity of Science and Technology Beijing. Beijing, China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1994年第3期220-228,共9页
By use of the self-consistent method of linear muffin-tin orbitals with the atomic sphere approximation on the basis of density functional theory, the total energies and the electron-ic sTructures ofNi, Al, and their ... By use of the self-consistent method of linear muffin-tin orbitals with the atomic sphere approximation on the basis of density functional theory, the total energies and the electron-ic sTructures ofNi, Al, and their hydrides NiH. A1H and Ni3AlH are calculated. The theoretical excess energies and the lattice strains due to hydrogen absorption consequently obtained from the ah initio results indicate that Ni is a better hydrogen absorber than Al, an. the absorptivity of Ni3Al dramatically decreases owing to the repulsion between Al and H On the other hand, the changes of band structures due to hydrogenation are found to be remparkable except that tor Al. and they are shown to be the qualitative manifestation of existing conclusions from photoemission experiments. 展开更多
关键词 total energy electronic structure hydrogenized Ni. Ai. Ni3Al
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Assessing Cleaner Energy Alternatives for Bus Transit in Rio de Janeiro:A Life Cycle Inventory Analysis
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作者 Marcio de Almeida D’Agosto Cintia Machado de Oliveira +1 位作者 Fabiana do Couto Assumpcao Ana Carolina Peixoto Deveza 《Journal of Environmental Protection》 2015年第11期1197-1218,共22页
From 2003 to 2009 in Brazilian municipalities of over 60,000 inhabitants, buses accounted for more than 25% of urban trips. This trend is not expected to change in the medium term. Worldwide, buses rely on petroleum d... From 2003 to 2009 in Brazilian municipalities of over 60,000 inhabitants, buses accounted for more than 25% of urban trips. This trend is not expected to change in the medium term. Worldwide, buses rely on petroleum diesel as fuel. In Brazil, alternative fuels such as biodiesel, natural gas and ethanol are available and the choice among them should depend on the assessment of the entire life cycle of such fuels. This paper uses a Life Cycle Inventory, which is essential to the implementation of a Life Cycle Assessment, to assess six energy alternatives: petroleum diesel, biodiesel, petroleum diesel with 5% of biodiesel, compressed natural gas, additivated hydrous ethanol and dual-fuel system composed by petroleum diesel with 5% of biodiesel and compressed natural gas. In saving total energy consumption, pure petroleum diesel or mixed with 5% biodiesel and dual-fuel systems stand out, in that order. If renewable energy use and net carbon dioxide emissions reduction are the goals, ethanol and biodiesel should be given preference. The addition of 5% of biodiesel in petroleum diesel increases the share of renewable energy in the supply chain of petroleum diesel by 47.5% with an increase of 0.58% in total energy consumption and a reduction of 3.8% in net CO2 emissions during the life cycle. In the case of biodiesel, the addition of 5% of biodiesel in petroleum diesel increases the share of renewable energy in the supply chain by 51.15% with an increase of 0.03% in the total energy consumption and a decrease of 7% in net CO2 emissions in the life cycle. The use of 5% of biodiesel in petroleum diesel does not significantly affect the use of renewable energy (+0.69%) or total energy consumption (+0.04%) in ethanol supply chain, which already shows a great use of renewable energy input. However, a decrease of 9.29% in the net CO2 emissions in the supply chain occurs, which reaches 5.28% in the life cycle. 展开更多
关键词 Renewable energy total energy Public Transportation Biofuels Life Cycle
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Rapid diagnostic method for transplutonium isotope production in high flux reactors 被引量:3
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作者 Qing-Quan Pan Qing-Fei Zhao +3 位作者 Lian-Jie Wang Bang-Yang Xia Yun Cai Xiao-Jing Liu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第3期125-142,共18页
Transplutonium isotopes are scarce and need to be produced by irradiation in high flux reactors.However,their production is inefficient,and optimization studies are necessary.This study analyzes the physical nature of... Transplutonium isotopes are scarce and need to be produced by irradiation in high flux reactors.However,their production is inefficient,and optimization studies are necessary.This study analyzes the physical nature of transplutonium isotope produc-tion using ^(252)Cf,^(244)Cm,^(242)Cm,and ^(238)Pu as examples.Traditional methods based on the Monte Carlo burnup calculation have the limitations of many calculations and cannot analyze the individual energy intervals in detail;thus,they cannot sup-port the refined evaluation,screening,and optimization of the irradiation schemes.After understanding the physical nature and simplifying the complexity of the production process,we propose a rapid diagnostic method for evaluating radiation schemes based on the concepts“single energy interval value(SEIV)”and“energy spectrum total value(ESTV)”.The rapid diagnostic method not only avoids tedious burnup calculations,but also provides a direction for optimization.The optimal irradiation schemes for producing ^(252)Cf,^(244)Cm,^(242)Cm,and ^(238)Pu are determined based on a rapid diagnostic method.Optimal irradiation schemes can significantly improve production efficiency.Compared with the initial scheme,the optimal scheme improved the production efficiency of ^(238)Pu by 7.41 times;^(242)Cm,11.98 times;^(244)Cm,65.20 times;and ^(252)Cf,15.08 times.Thus,a refined analysis of transplutonium isotope production is conducted and provides a theoretical basis for improving production efficiency. 展开更多
关键词 Transplutonium isotope Rapid diagnostic method Production optimization Single energy interval value energy spectrum total value
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Measurement of the Thermic Effect of Food in a Chinese Mixed Diet in Young People
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作者 TIAN Ying CAO Hong Peng +5 位作者 HUAN Yu Ping GONG Jia Wei YUAN Kai Hua CHEN Wen Zhuo HU Jing SHI Yu Fei 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2023年第7期585-594,共10页
Objective To determine the thermic effect of food(TEF)in a Chinese mixed diet in young people.Methods During the study,the participants were weighed and examined for body composition every morning.The total energy exp... Objective To determine the thermic effect of food(TEF)in a Chinese mixed diet in young people.Methods During the study,the participants were weighed and examined for body composition every morning.The total energy expenditure(TEE)of the participants was measured by the doubly labeled water method for 7 days,and during this period,basal energy expenditure was measured by indirect calorimetry and physical activity energy expenditure was measured by an accelerometer.The value obtained by subtracting basal energy expenditure and physical activity energy expenditure from TEE was used to calculate TEF.Results Twenty healthy young students(18–30 years;10 male)participated in the study.The energy intake of the participants was not significantly different from the Chinese Dietary Reference Intake of energy(P>0.05).The percentage of energy from protein,fat and carbohydrate were all in the normal range.The intakes of fruits,milk and dietary fiber of the participants were significantly lower than those in the Chinese Dietary Guidelines(P<0.05).There was no significant difference in the body weight of the participants during the experiment(P>0.05).When adjusted for body weight,there was no significant difference in either TEE or basal energy expenditure between the male and female participants(P>0.05).In addition,there was no significant difference in physical activity energy expenditure and TEF between the male and female participants(P>0.05).The percentage of TEF in TEE was 8.73%.Conclusion The percentage of TEF in TEE in a Chinese mixed diet in young people was significantly lower than 10%(P<0.001).A value of 10%is usually considered to be the TEF in mixed diets as a percentage of TEE. 展开更多
关键词 Thermic effect of food Chinese mixed diet total energy expenditure Basal energy expenditure Physical activity energy expenditure Doubly labeled water
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总能量守恒与辛几何算法(英文) 被引量:1
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作者 季仲贞 王 斌 +1 位作者 赵 颖 杨宏伟 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2002年第3期459-467,共9页
Based on the principle of total energy conservation, we give two important algorithms, the total energy conservation algorithm and the symplectic algorithm, which are established for the spherical shallow water equati... Based on the principle of total energy conservation, we give two important algorithms, the total energy conservation algorithm and the symplectic algorithm, which are established for the spherical shallow water equations. Also, the relation between the two algorithms is analyzed and numerical tests show the efficiency of the algorithms. 展开更多
关键词 Atmospheric and oceanic equations Conservative system Symplectic scheme total energy conservation Hamiltonian system
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Stokes方程组的解在四种半无穷柱体上空间衰减性 被引量:1
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作者 李远飞 陈雪姣 +1 位作者 张文彬 李丹丹 《Chinese Quarterly Journal of Mathematics》 2022年第1期61-73,共13页
This paper investigates the spatial behavior of the solutions of the Stokes equations in a semi-infinite cylinder.We consider four kinds of semi-infinite cylinders with boundary conditions of Dirichlet type.For each t... This paper investigates the spatial behavior of the solutions of the Stokes equations in a semi-infinite cylinder.We consider four kinds of semi-infinite cylinders with boundary conditions of Dirichlet type.For each type of cylinder we obtain the spatial decay estimates for the solutions.To make the attenuation meaningful,we derive the explicit bound for the total energy in terms of the initial boundary data. 展开更多
关键词 Spatial decay estimates Stokes equations total energy
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Three-dimensional potential energy surface for fission of^(236)U within covariant density functional theory 被引量:1
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作者 周明晖 李泽宇 +2 位作者 陈盛远 陈永静 李志攀 《Chinese Physics C》 SCIE CAS CSCD 2023年第6期143-149,共7页
We calculate the three-dimensional potential energy surface(PES)for the fission of the compound nucleus^(236)U using covariant density functional theory with constraints on the axial quadrupole and octupole deformatio... We calculate the three-dimensional potential energy surface(PES)for the fission of the compound nucleus^(236)U using covariant density functional theory with constraints on the axial quadrupole and octupole deformations(β_(2),β_(3))coexistence of the elongated and compact fission modes is predicted for comes shallow across a large range of quadrupole and octupole deformations for small scission line in the(β_(2),β_(3))plane extends to a shallow band,leading to fluctuations of several to ten MeV in the estimated total kinetic energies and of several to approximately ten nucleons in the fragment masses. 展开更多
关键词 multi-dimensional potential energy surface covariant density functional theory SCISSION total kinetic energy
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Accurate calculations of the helium atom in magnetic fields
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作者 赵继军 王晓峰 乔豪学 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第11期256-263,共8页
The 1^10^+ 1^1(-1)^+and 1^1(2)^+ states of the helium atom in the magnetic field regime between 0 and 100 a.u. are studied using a full configuration-interaction (CI) approach. The total energies, derivatives... The 1^10^+ 1^1(-1)^+and 1^1(2)^+ states of the helium atom in the magnetic field regime between 0 and 100 a.u. are studied using a full configuration-interaction (CI) approach. The total energies, derivatives of the total energy with respect to the magnetic field and ionisation energies are calculated with Hylleraas-like functions in spherical coordinates in low to intermediate fields and Hylleraas Caussian functions in cylindrical coordinates in intermediate to high fields, respectively. In intermediate fields, the total energies and ionisation energies are determined in terms of Hermite interpolation, based on the results obtained with the two above-mentioned basis functions. Calculations show that the current method can produce lower total energies and larger ionisation energies, and make the two ionisation energy curves obtained with the two above-mentioned basis functions join smoothly in intermediate fields. Comparisons are also made with previous works. 展开更多
关键词 strong magnetic field helium atom total energy ionisation energy
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High accuracy calculation of the hydrogen negative ion in strong magnetic fields
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作者 赵继军 王晓峰 乔豪学 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第5期222-226,共5页
Using a full configuration-interaction method with Hylleraas-Gaussian basis function, this paper investigates the 1^10^+, 1^1(-1)^+ and 1^1(-2)6+ states of the hydrogen negative ion in strong magnetic fields. T... Using a full configuration-interaction method with Hylleraas-Gaussian basis function, this paper investigates the 1^10^+, 1^1(-1)^+ and 1^1(-2)6+ states of the hydrogen negative ion in strong magnetic fields. The total energies, electron detachment energies and derivatives of the total energy with respect to the magnetic field are presented as functions of magnetic field over a wide range of field strengths. Compared with the available theoretical data, the accuracy for the energies is enhanced significantly. The field regimes 3 〈 γ 〈 4 and 0.02 〈 γ 〈 0.05, in which the 1^1(-1)6+ and 1^1(-2)^+ states start to become bound, respectively, are also determined based on the calculated electron detachment energies. 展开更多
关键词 strong magnetic field hydrogen negative ion total energy electron detachment energy
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Growth Dynamics and Optimal Harvesting Stage of Two Forage Maize Varieties
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作者 FU Feng-ling GUO Chang-jun TANG Qi-ling LIU Jian LI Wan-chen 《Agricultural Sciences in China》 CAS CSCD 2011年第2期220-227,共8页
SAUMZ 1 and SAUMZ 2 are two forage maize varieties reproduced by distant hybridization.In a randomized block experiment,their fresh forage yield and dry matter yield were investigated on the basis of growth period,lea... SAUMZ 1 and SAUMZ 2 are two forage maize varieties reproduced by distant hybridization.In a randomized block experiment,their fresh forage yield and dry matter yield were investigated on the basis of growth period,leaf stage,and effective accumulated temperature.The nutritional components were measured in a near infrared diffuse reflectance spectroscopy.Referring to the concept of forage grading index,a formula was constructed to calculate the total digestible energy.The investigated characters and indexes were adapted to suitable models of growth dynamics.The results showed that these two varieties have strong heterosis in fresh forage yield,dry matter yield,and total digestible energy.Their growth dynamics were adapted to Logistic models described by general equation y=k/(1+ae-bx).The forage grading indexes of these two varieties were decreased linearly along with the increasing of their leaf stage.The stopping point of fast growing period of total digestible energy estimated on the basis of leaf stage was suggested to be used as optimal harvesting stage of forage maize.The optimal harvesting stage was estimated to be tasseling stage for SAUMZ 1 and 19.50-leaf stage for SAUMZ 2. 展开更多
关键词 forage maize growth dynamics leaf stage optimal harvest stage total digestible energy
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