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Impact of alloy-like phase on energy loss mitigation in multi-component organic photovoltaics
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作者 Xiangyue Kong Lingling Zhan +10 位作者 Zhongjie Li Yaxin Yang Yuhao Liu Huayu Qiu Xiaokang Sun Hanlin Hu Rui Sun Jie Min Shouchun Yin Weifei Fu Hongzheng Chen 《Aggregate》 EI CAS 2024年第4期339-348,共10页
The multi-component strategy has proven effective in advancing the performance of organic photovoltaics(OPVs),enhancing photocurrent andfill factor through spectral complementarity and morphology optimization.However,t... The multi-component strategy has proven effective in advancing the performance of organic photovoltaics(OPVs),enhancing photocurrent andfill factor through spectral complementarity and morphology optimization.However,the open-circuit voltage(VOC)mechanism in multi-component systems lacks systematic investiga-tion.In this study,we explore the influence of alloy-like phases on energy level distribution and energy loss mechanisms in multi-component OPVs.Appropriate modulation of donor alloy-like phases maintains the original intermolecular stack-ing,enhances component compatibility,reduces acceptor aggregation,and improves acceptor phase purity,mitigating non-radiative recombination losses.Additionally,suitable alloy-like phase modulation elevates charge transfer(CT)states,reducing the gap between CT and local exciton state,lowering reorganization energy,and alleviating radiative recombination loss below the bandgap.Through synergistic optimization(layer-by-layer method with solid additive),ternary devices based on Y6 acceptor achieve a notable 19.41%power conversion efficiency,offering new insights for the analysis of the energy loss of the multi-component OPVs. 展开更多
关键词 alloy-like phase charge transfer state energy loss high efficiencies multi-donors
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The medium-temperature dependence of jet transport coefficient in high-energy nucleus-nucleus collisions
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作者 Man Xie Qing-Fei Han +2 位作者 En-Ke Wang Ben-Wei Zhang Han-Zhong Zhang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第7期173-191,共19页
The medium-temperature T dependence of the jet transport coefficient̂q was studied via the nuclear modification factor RAA(p_(T))and elliptical flow parameter v_(2)(p_(T))for large transverse momentum p_(T) hadrons in... The medium-temperature T dependence of the jet transport coefficient̂q was studied via the nuclear modification factor RAA(p_(T))and elliptical flow parameter v_(2)(p_(T))for large transverse momentum p_(T) hadrons in high-energy nucleus-nucleus collisions.Within a next-to-leading-order perturbative QCD parton model for hard scatterings with modified fragmentation functions due to jet quenching controlled by q,we check the suppression and azimuthal anisotropy for large p_(T) hadrons,and extract q by global fits to RAA(pT)and v_(2)(pT)data in A+A collisions at RHIC and LHC,respectively.The numerical results from the best fits show that q∕T^(3) goes down with local medium-temperature T in the parton jet trajectory.Compared with the case of a constant q∕T^(3),the going-down T dependence of q∕T^(3) makes a hard parton jet to lose more energy near T_(c) and therefore strengthens the azimuthal anisotropy for large pT hadrons.As a result,v_(2)(p_(T))for large pT hadrons was enhanced by approximately 10%to better fit the data at RHIC/LHC.Considering the first-order phase transition from QGP to the hadron phase and the additional energy loss in the hadron phase,v_(2)(p_(T))is again enhanced by 5-10%at RHIC/LHC. 展开更多
关键词 Jet quenching Jet transport parameter Hadron suppression Elliptic flow coefficient energy loss asymmetry
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Two-Stage Optimal Scheduling of Community Integrated Energy System
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作者 Ming Li Rifucairen Fu +4 位作者 Tuerhong Yaxiaer Yunping Zheng Abiao Huang Ronghui Liu Shunfu Lin 《Energy Engineering》 EI 2024年第2期405-424,共20页
From the perspective of a community energy operator,a two-stage optimal scheduling model of a community integrated energy system is proposed by integrating information on controllable loads.The day-ahead scheduling an... From the perspective of a community energy operator,a two-stage optimal scheduling model of a community integrated energy system is proposed by integrating information on controllable loads.The day-ahead scheduling analyzes whether various controllable loads participate in the optimization and investigates the impact of their responses on the operating economy of the community integrated energy system(IES)before and after;the intra-day scheduling proposes a two-stage rolling optimization model based on the day-ahead scheduling scheme,taking into account the fluctuation of wind turbine output and load within a short period of time and according to the different response rates of heat and cooling power,and solves the adjusted output of each controllable device.The simulation results show that the optimal scheduling of controllable loads effectively reduces the comprehensive operating costs of community IES;the two-stage optimal scheduling model can meet the energy demand of customers while effectively and timely suppressing the random fluctuations on both sides of the source and load during the intra-day stage,realizing the economic and smooth operation of IES. 展开更多
关键词 Integrated energy system two-stage optimal scheduling controllable loads rolling optimization
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The Correlation between the Power Quality Indicators and Entropy Production Characteristics of Wind Power+Energy Storage Systems
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作者 Caifeng Wen Boxin Zhang +3 位作者 Yuanjun Dai Wenxin Wang Wanbing Xie Qian Du 《Energy Engineering》 EI 2024年第10期2961-2979,共19页
Power quality improvements help guide and solve the problems of inefficient energy production and unstable power output in wind power systems.The purpose of this paper is mainly to explore the influence of different e... Power quality improvements help guide and solve the problems of inefficient energy production and unstable power output in wind power systems.The purpose of this paper is mainly to explore the influence of different energy storage batteries on various power quality indicators by adding different energy storage devices to the simulated wind power system,and to explore the correlation between systementropy generation and various indicators,so as to provide a theoretical basis for directly improving power quality by reducing loss.A steady-state experiment was performed by replacing the wind wheel with an electric motor,and the output power qualities of the wind power systemwith andwithout energy storagewere compared and analyzed.Moreover,the improvement effect of different energy storage devices on various indicatorswas obtained.Then,based on the entropy theory,the loss of the internal components of the wind power system generator is simulated and explored by Ansys software.Through the analysis of power quality evaluation indicators,such as current harmonic distortion rate,frequency deviation rate,and voltage fluctuation,the correlation between entropy production and each evaluation indicator was explored to investigate effective methods to improve power quality by reducing entropy production.The results showed that the current harmonic distortion rate,voltage fluctuation,voltage deviation,and system entropy production are positively correlated in the tests and that the power factor is negatively correlated with system entropy production.In the frequency range,the frequency deviationwas not significantly correlated with the systementropy production. 展开更多
关键词 Wind power system entropy production system losses power quality indexes battery energy storage
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Frequency Loss and Recovery in Rolling Bearing Fault Detection 被引量:4
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作者 Aijun Hu Ling Xiang +1 位作者 Sha Xu Jianfeng Lin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第2期145-156,共12页
Rolling element bearings are key components of mechanical equipment. The bearing fault characteristics are a ected by the interaction in the vibration signals. The low harmonics of the bearing characteristic frequenci... Rolling element bearings are key components of mechanical equipment. The bearing fault characteristics are a ected by the interaction in the vibration signals. The low harmonics of the bearing characteristic frequencies cannot be usually observed in the Fourier spectrum. The frequency loss in the bearing vibration signal is presented through two independent experiments in this paper. The existence of frequency loss phenomenon in the low frequencies, side band frequencies and resonant frequencies and revealed. It is demonstrated that the lost frequencies are actually suppressed by the internal action in the bearing fault signal rather than the external interference. The amplitude and distribution of the spectrum are changed due to the interaction of the bearing fault signal. The interaction mechanism of bearing fault signal is revealed through theoretical and practical analysis. Based on mathematical morphology, a new method is provided to recover the lost frequencies. The multi-resonant response signal of the defective bearing are decomposed into low frequency and high frequency response, and the lost frequencies are recovered by the combination morphological filter(CMF). The e ectiveness of the proposed method is validated on simulated and experimental data. 展开更多
关键词 rolling element BEARING Signal processing FREQUENCY loss Fault detection MORPHOLOGICAL filter
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Energy loss of degrader in SC200 proton therapy facility 被引量:2
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作者 Feng Jiang Yun-Tao Song +4 位作者 Jin-Xing Zheng Xian-Hu Zeng Peng-Yu Wang Jun-Sheng Zhang Wu-Quan Zhang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第1期11-18,共8页
The proton beam energy determines the range of particles and thus where the dose is deposited. According to the depth of tumors, an energy degrader is needed to modulate the proton beam energy in proton therapy facili... The proton beam energy determines the range of particles and thus where the dose is deposited. According to the depth of tumors, an energy degrader is needed to modulate the proton beam energy in proton therapy facilities based on cyclotrons, because the energy of beam extracted from the cyclotron is fixed. The energy loss was simulated for the graphite degrader used in the beamline at the superconducting cyclotron of 200 MeV in Hefei(SC200). After adjusting the mean excitation energy of the graphite used in the degrader to 76 eV, we observed an accurate match between the simulations and measurements.We also simulated the energy spread of the degraded beam and the transmission of the degrader using theoretical formulae. The results agree well with the Monte Carlo simulation. 展开更多
关键词 Degrader energy loss Mean EXCITATION energy energy SPREAD Transmission
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Constraining the colored cc energy loss from J/Ψ production in p-A collisions 被引量:2
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作者 Li-Hua Song Lin-Wan Yan Ying Liu 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第11期205-213,共9页
Considering the volatility of the propagation path for charmonium passing across the nuclear target in J/ψ formation from p-A collisions, the charmonium energy loss is investigated using Salgado-Wiedemann quenching w... Considering the volatility of the propagation path for charmonium passing across the nuclear target in J/ψ formation from p-A collisions, the charmonium energy loss is investigated using Salgado-Wiedemann quenching weights. A successful description regarding J/ψsuppression of R_(w(Fe)/Be)(x_F) from the E866 experiment for 0.2 <x_F<0.65 gives the transport coefficient q = 0.29 ± 0.07 GeV^2/fm for the colored cc energy loss.The calculated result indicates that radiative energy loss of a parton should be independent of its mass at high energy.The calculations are further compared to LHC and RHIC measurements. 展开更多
关键词 J/Ψproduction energy loss CHARM QUARK GLUON
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Calculation of the Energy Loss for Tip Leakage Flow in Turbines 被引量:2
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作者 Mohsen Hassanvand 王松涛 +1 位作者 冯国泰 王仲奇 《Chinese Journal of Aeronautics》 SCIE EI CSCD 2004年第3期142-148,共7页
A commercial N-S solver has been employed for simulation and investigation ofthe unsteady flow field inside the tip clearance of a turbine rotor. The main objective of thispaper is to introduce a new method of energy ... A commercial N-S solver has been employed for simulation and investigation ofthe unsteady flow field inside the tip clearance of a turbine rotor. The main objective of thispaper is to introduce a new method of energy loss calculation for the flow field in tip clearanceregion of a turbine rotor blade. This method can be easily used in all kinds of flow fields. Regionsof high viscous effects have been found to be located near the shroud rather than the blade tip. Itis shown that the time-averaged loss of energy in tip leakage flow is dissimilar for differentrotor blades. This result is a helpful hint that can be taken by blade designers to designnon-uniform rotor blades with different geometric and aerodynamic loads to minimize the energy loss. 展开更多
关键词 tip leakage flow tip clearance unsteady flow energy loss
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Relation between oxidation microstructure and the maximum energy product loss of a Sm_2Co_(17) magnet oxidized at 500℃ 被引量:1
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作者 刘丽丽 蒋成保 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第12期416-420,共5页
The oxidation microstructure and maximum energy product (BH)max loss of a 8m(Co0.76, Fe0.1, Cu0.1, Zr0.04)7 magnet oxidized at 500 ℃ were systematically investigated. Three different oxidation regions were formed... The oxidation microstructure and maximum energy product (BH)max loss of a 8m(Co0.76, Fe0.1, Cu0.1, Zr0.04)7 magnet oxidized at 500 ℃ were systematically investigated. Three different oxidation regions were formed in the oxidized magnet: a continuous externM oxide scale, an internal reaction layer, and a diffusion zone. Both room-temperature and high-temperature (BH)max losses exhibited the same parabolic increase with oxidation time. An oxygen diffusion model was proposed to simulate the dependence of (BH)max loss on oxidation time. It is found that the external oxide scale has little effect on the (BH)max loss, and both the internal reaction layer and diffusion zone result in the (BH)max loss. Moreover, the diffusion zone leads to more (BH)max loss than the internal reaction layer. The values of the oxidation rate constant k for internal reaction layer and oxygen diffusion coefficient D for diffusion zone were obtained, which are about 1.91×10^-10 cm^2/s and 6.54×10^-11 cm^2/s, respectively. 展开更多
关键词 Sm2Co17 magnet maximum energy product loss internal reaction layer diffusion zone
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Magnetostrictive and Kinematic Model Considering the Dynamic Hysteresis and Energy Loss for GMA 被引量:3
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作者 Huifang LIU Xingwei SUN +2 位作者 Yifei GAO Hanyu WANG Zijin GAO 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第2期241-255,共15页
Due to the influence of magnetic hysteresis and energy loss inherent in giant magnetostrictive materials (GMM), output displacement accuracy of giant magnetostrictive actuator (GMA) can not meet the precision and ... Due to the influence of magnetic hysteresis and energy loss inherent in giant magnetostrictive materials (GMM), output displacement accuracy of giant magnetostrictive actuator (GMA) can not meet the precision and ultra precision machining. Using a GMM rod as the core driving element, a GMA which may be used in the field of precision and ultra precision drive engineering is designed through modular design method. Based on the Armstrong theory and elastic Gibbs free energy theory, a nonlinear magnetostriction model which considers magnetic hysteresis and energy loss characteristics is established. Moreover, the mechanical system differential equation model for GMA is established by utilizing D'Alembert's principle. Experimental results show that the model can preferably predict magnetization property, magnetic potential orientation, energy loss for GMM. It is also able to describe magnetostrictive elongation and output displacement of GMA. Research results will provide a theoretical basis for solving the dynamic magnetic hysteresis, energy loss and working precision for GMA fundamentally. 展开更多
关键词 Giant magnetostrictive actuator · Kinematic model · Magnetostrictive model · Magnetic hysteresis · energy loss
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Energy loss of an energetic Ga ion in hot Au plasmas 被引量:1
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作者 Bin He Xujun Meng Jianguo Wang 《Matter and Radiation at Extremes》 SCIE EI CAS 2016年第5期257-263,共7页
Self-consistent calculations of energy loss for a Ga ion moving in hot Au plasmas are made under the assumption of wide ranges of the projectile energy and the plasma temperature with all important mechanisms consider... Self-consistent calculations of energy loss for a Ga ion moving in hot Au plasmas are made under the assumption of wide ranges of the projectile energy and the plasma temperature with all important mechanisms considered in detail.The relevant results are found to be quite different from those of an a particle or a proton.One important reason for this is the rapid increasing of the charge state of a Ga ion at plasma temperature.This reason also leads to the inelastic stopping which does not always decrease with the increase of plasma temperature,unlike the case of an a particle.The nuclear stopping becomes very important at high enough plasma temperature due to the heavy reduced mass of a Ga and an Au ion and the above-mentioned reason.The well-known binary collision model[Phys.Rev.126(1962)1]and its revised one[Phys.Rev.A 29(1984)2145]are not working or unsatisfactory in this case. 展开更多
关键词 energy loss Hot Au plasma Ga ion
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Optimization of Maturation of Radio-Cephalic Arteriovenous Fistula Using a Model Relating Energy Loss Rate and Vascular Geometric Parameters 被引量:1
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作者 Yang Yang Nellie Della Schiava +4 位作者 Pascale Kulisa Mahmoud El Hajem Benyebka Bou-Saïd Serge Simoëns Patrick Lermusiaux 《Journal of Biomedical Science and Engineering》 2021年第6期271-287,共17页
<span style="font-family:Verdana;">The main reason for the early failure of radio-cephalic arteriovenous fistula (RCAVF) is non-maturity, which means that the blood flow rate in the fistula cannot incr... <span style="font-family:Verdana;">The main reason for the early failure of radio-cephalic arteriovenous fistula (RCAVF) is non-maturity, which means that the blood flow rate in the fistula cannot increase to the expected value for dialysis. From a mechanical perspective, the vascular resistance at the artificially designed anastomosis causes an energy loss that affects blood flow rate growth and leads to early failure. This research studied how to maximize the RCAVF maturity and primary patency by controlling the energy loss rate. We theoretically analyzed and derived a model that evaluates the energy loss rate <em>E</em><sub><em>avf</em></sub> in RCAVF as a function of its blood vessel geometric parameters (GPs) for given flow rates. There was an aggregate of five controllable GPs in RCAVF: radial artery diameter (<em>D</em><sub><em>ra</em></sub>), cephalic vein diameter (<em>D</em><sub><em>cv</em></sub>), blood vessel distance between artery and vein (<em>h</em>), anastomotic diameter (<em>D</em><sub><em>a</em></sub>), and anastomotic angle (<em>θ</em>). Through this analysis, it was found that <em>E</em><sub><em>avf</em></sub> was inversely proportional to <em>D</em><sub><em>ra</em></sub>, <em>D</em><sub><em>cv</em></sub>, <em>D</em><sub><em>a</em></sub>, and <em>θ</em>, whereas proportional to <em>h</em>. Therefore, we recommended surgeons choose the vessels with large diameters, close distance, and increase the diameter and angle of the anastomosis to decrease the early failure of RCAVF. Simultaneously, we could explain the results of many clinical empiricisms with our formula. We found that increasing <em>D</em><sub><em>cv</em></sub> and <em>θ</em> was more significant in reducing <em>E</em><sub><em>avf</em></sub> than increasing <em>D</em><sub><em>ra</em></sub> and <em>D</em><sub><em>a</em></sub>. Based on our model, we could define two critical energy loss rates (<em>CEL</em><sub><em>a</em></sub>, <em>CEL</em><sub><em>b</em></sub>) to help surgeons evaluate the blood vessels and choose the ideal range of <em>θ</em>, and help them design the preoperative RCAVF plan for each patient to increase the maturity and the primary patency of RCAVF.</span> 展开更多
关键词 HEMODIALYSIS Radio-Cephalic Arteriovenous Fistula (RCAVF) Critical energy loss Rate (CEL) Vessel Geometric Parameters MATURITY
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Managing System Losses to Improve Energy Efficiency within the Electricity Company of Ghana (ECG) Limited 被引量:1
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作者 Vincent Kwame Osei-Appiah Jones Lewis Arthur 《Smart Grid and Renewable Energy》 2022年第6期121-136,共16页
The inability to achieve the target of universal access to electricity is influenced by several factors including funding limitations, the use of obsolete equipment, power theft, and system losses confronting the elec... The inability to achieve the target of universal access to electricity is influenced by several factors including funding limitations, the use of obsolete equipment, power theft, and system losses confronting the electricity distribution services of the Electricity Company of Ghana Limited (ECG). The study assessed the components of system losses within the ECG by determining and computing the percentage of system losses within ECG, examining the causes of both commercial and technical losses in ECG, and determining ways to improve energy efficiency by reducing system losses in the most cost-efficient manner. The study adopted deductive reasoning and a quantitative approach to guide data collection and analysis of the research output. A sample of 345 technical and non-technical staff of ECG in the Greater Accra Metropolis was selected from a population of 2500. Purposive, simple random, and cluster sampling techniques were used in identifying and accessing respondents for the study. Descriptive statistics were applied to measure central tendency and degrees of dispersion and the Relative Importance Index (RII) to predict criterion and predictor variables. The impact of low voltage network losses can adversely contribute to technical losses (20%) and reduce energy efficiency in power or electricity distribution companies. Non-technical losses are mainly caused by illegal connections, meter problems, and billing problems. Each of the non-technical losses contributes a maximum of 10% to system losses. Contributors to system losses at ECG are ranked first for power theft and least for lack of incentives. System losses at ECG include metering inaccuracies, bad workmanship, unmetered supply, and lengthy distribution lines, each recording a mean value of above 3.5. Measures to improve monitoring of the networks and systems at ECG and discourage power theft should include an extensive quantification, patrolling, and inspection of the entire network to assess the extent of the network and conditions relevant for the placement of systematically planned maintenance programmes. 展开更多
关键词 Network Management System losses ELECTRICITY Cost Efficiency energy Management
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ENERGY-LOSS FUNCTIONS DERIVED FROM REELS SPECTRA FOR ALUMINUM
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作者 Z.M.Zhang Z.J.Ding +5 位作者 H.M.Li K.Salma X.Sun R.Shimizu T.Koshikawa K.Goto 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2005年第3期217-222,共6页
The effective energy loss functions for Al have been derived from differential i nverse inelastic mean free path based on the extended Landau approach. It has be en revealed that the effective energy loss function is ... The effective energy loss functions for Al have been derived from differential i nverse inelastic mean free path based on the extended Landau approach. It has be en revealed that the effective energy loss function is very close in value to th e theoretical surface energy loss function in the lower energy loss region but g radually approaches the theoretical bulk energy loss function in the higher ener gy loss region. Moreover, the intensity corresponding to surface excitation in e ffective energy loss functions decreases with the increase of primary electron e nergy. These facts show that the present effective energy loss function describe s not only surface excitation but also bulk excitation. At last, REELS spectra s imulated by Monte Carlo method based on use of the effective energy loss functio ns has reproduced the experimental REELS spectra with considerable success. 展开更多
关键词 effective energy loss function Monte Carlo simulation extended Landau approach reflection electron energy loss spectro scopy ALUMINUM
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Energy loss on of low energy ion N^+q grazing the A1(111) surface
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作者 胡碧海 陈春花 +1 位作者 宋玉收 顾建刚 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第5期1285-1289,共5页
The total energy loss of N^+q ions (for v 〈 Bohr velocity) grazing on the Al(111) has been simulated without any 'fit' parameter and compared with the experimental data. The energy loss due to the charge excha... The total energy loss of N^+q ions (for v 〈 Bohr velocity) grazing on the Al(111) has been simulated without any 'fit' parameter and compared with the experimental data. The energy loss due to the charge exchange, happening before the N^+q hits the Al(111) surface, is studied. The present simulation shows that the energy loss strongly depends on the charge state of the projectile and the lattice orientation of Al(111) surface. The calculated total energy loss agrees with experimental data very well. 展开更多
关键词 energy loss charge exchange GRAZING
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Neutrino energy loss by electron capture on strongly screened iron group nuclei
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作者 刘晶晶 罗志全 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第12期3624-3630,共7页
The influences on the neutrino energy loss rates in iron group nuclei at the same density are investigated in the presence of strong electron screening and in the absence of electron screening. The results show that a... The influences on the neutrino energy loss rates in iron group nuclei at the same density are investigated in the presence of strong electron screening and in the absence of electron screening. The results show that at a temperature of 15 × 10^9 K, the neutrino energy loss rates which come from the electron capture process for most iron group nuclei decrease no more than 2 orders of magnitude but for the others (such as ^53,55,56,57,58,59,6o Co, ^56,59Ni) they can decrease about 3 orders of magnitude due to strong electron screening (SES), whereas, at a temperature of 10^9K the neutrino energy loss rates of the most iron group nuclei can be diminished greatly due to the SES. For example, ^61Fe, ^60Fe, and ^62Ni the neutrino energy loss rates decrease about 4, 15 and 16 orders of magnitude and for ^57Cr, ^58Cr, and ^60Cr decrease about 18, 12, and 10 orders of magnitude respectively. According to our calculations the neutrino energy loss rates of nuclei ^58Mn, ^59Mn, ^60Mn, and ^62Mn may decrease about 13 orders of magnitude at a temperature of 10^9 K due to the SES. 展开更多
关键词 neutrino energy loss strong electron screening electron capture
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Internal Energy Losses and Contact Duration About a Circular Plate Colliding to a Half-Plane Target
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作者 吕中杰 《Journal of Beijing Institute of Technology》 EI CAS 2009年第3期253-257,共5页
Collisions between multibody systems are irreversible processes which cause loss of internal energy by a stress wave that propagates in the impacting bodies away from the region of impact. A coefficient of restitution... Collisions between multibody systems are irreversible processes which cause loss of internal energy by a stress wave that propagates in the impacting bodies away from the region of impact. A coefficient of restitution relating to approach velocity is introduced to denote the losses of translational kinetic energy. A parameter β involved in internal energy losses has been obtained to calculate the coefficient of restitution. As a result, the internal energy losses caused by elastic stress waves and the contact duration in metals can be calculated numerically for the collision between circular cylinder and half plane. The metals include aluminum alloys, steel-mild 1020, steel-stainless austenitic 304, tungsten alloys, copper alloys, nickel alloys and titanium alloys. By introducing a coefficient of velocity-frequency, an exponential aggression equation related the normalized oscillating frequency and normalized approach velocity has been obtained by the numerical method. 展开更多
关键词 circular plate loss of internal energy elastic wave contact duration
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Large energy-loss straggling of swift heavy ions in ultra-thin active silicon layers 被引量:2
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作者 张战刚 刘杰 +13 位作者 侯明东 孙友梅 赵发展 刘刚 韩郑生 耿超 刘建德 习凯 段敬来 姚会军 莫丹 罗捷 古松 刘天奇 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第9期505-511,共7页
Monte Carlo simulations reveal considerable straggling of energy loss by the same ions with the same energy in fully-depleted silicon-on-insulator (FDSOI) devices with ultra-thin sensitive silicon layers down to 2.5... Monte Carlo simulations reveal considerable straggling of energy loss by the same ions with the same energy in fully-depleted silicon-on-insulator (FDSOI) devices with ultra-thin sensitive silicon layers down to 2.5 rim. The absolute straggling of deposited energy decreases with decreasing thickness of the active silicon layer. While the relative straggling increases gradually with decreasing thickness of silicon films and exhibits a sharp rise as the thickness of the silicon film descends below a threshold value of 50 nm, with the dispersion of deposited energy ascending above ~10%. Ion species and energy dependence of the energy-loss straggling are also investigated. For a given beam, the dispersion of deposited energy results in large uncertainty on the actual linear energy transfer (LET) of incident ions, and thus single event effect (SEE) responses, which pose great challenges for traditional error rate prediction methods. 展开更多
关键词 single event effects energy-loss straggling ultra-thin silicon layer Monte Carlo simulation
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Body Composition and Energy Expenditure Changes during Weight Loss: An Exploratory Study
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作者 Adrienne S. Thomas Jocelyn E. Holden Jo Carol Chezem 《Food and Nutrition Sciences》 2012年第2期153-156,共4页
The objective of this exploratory study was to describe changes in body composition and resting energy expenditure (REE) in adult women during weight reduction. A total of 69 client records were collected retrospectiv... The objective of this exploratory study was to describe changes in body composition and resting energy expenditure (REE) in adult women during weight reduction. A total of 69 client records were collected retrospectively from a 25 week commercial weight loss program that restricted calories to 90% of measured REE. Data analyzed included total body mass (TBM), fat mass (FM) and fat-free mass (FFM) from air displacement plethysmography;measured REE from indirect calorimetry;and predicted REE from linear regression. From baseline to week 25, there were significant declines in TBM (95.0 ± 24.1 kg to 87.2 ± 22.9 kg;P < 0.001) and FM (47.5 ± 18.5 kg to 39.9 ± 17.6 kg;P < 0.001). During the same time period, FFM remained unchanged (47.5 ± 7.3 kg to 47.2 ± 7.0 kg;P ≥ 0.05). REE was signify- cantly lower at weeks 13 (6595.2 ± 1312.1 kJ) and 25 (6608.2 ± 1404.6 kJ) compared to baseline (7117.4 ± 1471.5 kJ) (P < 0.001);however, REE at weeks 13 and 25 were similar (P ≥ 0.05). At weeks 13 and 25, predicted REE (6992.7 ± 1065.7 and 6939.2 ± 1056.0 kJ, respectively) was significantly higher than measured REE (6595.2 ± 1312.1 and 6608.2 ± 1404.6 kJ, respectively) (P < 0.001). The results of this study suggest that significant reduction in TBM is possible without the loss of FFM and that metabolic adaptation may occur during the process. 展开更多
关键词 energy METABOLISM BODY Composition Caloric RESTRICTION WEIGHT loss
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Method for Determination of Optimal Installed Capacity of Renewable Sources of Energy by the Criterion of Minimum Losses of Active Power in Distribution System
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作者 P. D. Lezhniuk V. A. Komar D. S. Sobchuk 《Energy and Power Engineering》 2014年第3期37-46,共10页
New method for determination of optimal placement and value of installed capacity of renewable source of energy (RES) by the criterion of minimum losses of active power, that allows taking into consideration the depen... New method for determination of optimal placement and value of installed capacity of renewable source of energy (RES) by the criterion of minimum losses of active power, that allows taking into consideration the dependence of RES on natural conditions of region, schedule of energy supply, parameters and configuration of distribution network is suggested in the paper. Results of computations of test scheme confirm the efficiency of the proposed method and its simplicity as compared with the methods considered in literature sources. 展开更多
关键词 Distributed Generation RENEWABLE Sources of energy Minimum lossES of Active Power
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