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
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
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
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
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>π</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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
基金supported by the projects of National Natural Science Foundation of China (No.30771811)the National Technology Research and Development Program in the Eleventh Five-Year Plan of China(No.2008BAI58B01)
文摘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.
文摘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.
基金supported by the National Natural Science Foundation of China under Grant 71804089the Humanities and Social Sciences Youth Foundation of Ministry of Education of China under Grants 18YJCZH034 and 19YJC790128+3 种基金the Jiangsu Postdoctoral Research Foundation underGrant 2018K195C,the Natural Science Foundation of Shandong Province in China under Grant ZR2020QG054the Graduate Education Quality Improvement Project of Shandong Province,China under Grants SDYKC19180 and SDYAL19180The project number of“The quality course in Financial Statistics”is SDYKC19180The project number of“Financial Literacy Oriented Case Library of Derivative Financial Instruments Teaching”is SDYAL19180.
文摘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.
文摘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 .
文摘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>π</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.
文摘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.
基金Fund Project in 2020,China(No.KKZ3202052058)and the support of Scientific Research Fund from Yunnan Education Department in China(No.2022J0064).
文摘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.
基金Supported by Tianjin Institute of Urban Construction(03046)
文摘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.
基金supported by the doctoral research initiation fund of Linyi University(Grant No.:204-40618051,Zhang,B.,http://www.lyu.edu.cn/).
文摘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%).
文摘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.
文摘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.
文摘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.
基金sponsored by Natural Science Foundation of Shanghai (NO.22ZR1431900)Science and Technology on Reactor System Design Technology Laboratory.
文摘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.
基金supported by Danone Fund for Dietary Nutrition Research and Education[DIC2021-03].
文摘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.
基金This project is supported by the National Key Planning Development Project for Basic tesearch(GrantNo.1999032801),the National Outstanding Youth Scientist Foundation of China(Grant No.49835109)and the Na-tional Natural Science Foundation of China(Grant
文摘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.
基金Supported by the Key Projects of Universities in Guangdong Province(NATURAL SCIENCE)(Grant No.2019KZDXM042)Research Team Project of Guangzhou Huashang College(Grant No.2021HSKT01).
文摘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.
基金Supported by the National Natural Science Foundation of China(11875225,11790325,11790320)the Special Fund from the China Nuclear Data Center+1 种基金the Fundamental Research Funds for the Central Universitiesthe Fok Ying-Tong Education Foundation。
文摘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.
基金Project supported by the National Natural Science Foundation of China (Grant No. 10874133)
文摘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.
基金Project supported by the National Natural Science Foundation of China (Grant No. 10874133)
文摘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.
基金the National Projects of Development Plan of the State Key Fundamental Research of China (973 Program,2009CB118400)
文摘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.