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Transition energy and dipole oscillator strength for 1s^22p-1s^2nd of Cr^(21+) ion 被引量:7
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作者 王治文 刘影 +2 位作者 胡木宏 李新汝 王亚男 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第8期2909-2913,共5页
The transition energies, wavelengths and dipole oscillator strengths of 1s^22p-1s^2nd (3 ≤ n ≤ 9) for Cr^21+ ion are calculated. The fine structure splittings of 1s^2nd (n ≤ 9) states for this ion are also cal... The transition energies, wavelengths and dipole oscillator strengths of 1s^22p-1s^2nd (3 ≤ n ≤ 9) for Cr^21+ ion are calculated. The fine structure splittings of 1s^2nd (n ≤ 9) states for this ion are also calculated. In calculating energy, we have estimated the higher-order relativistic contribution under a hydrogenic approximation. The quantum defect of Rydberg series 1s^2nd is determined according to the quantum defect theory. The results obtained in this paper excellently agree with the experimental data available in the literature. Combining the quantum defect theory with the discrete oscillator strengths, the discrete oscillator strengths for the transitions from initial state 1s^22p to highly excited 1s^2nd states (n ≥ 10) and the oscillator strength density corresponding to the bound-free transitions are obtained. 展开更多
关键词 Cr^21+ ion transition energy fine structure splitting quantum defect
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THE LINEAR CORRELATIONS BETWEEN ELECTRONIC TRANSITION ENERGY AND HAMMETT CONSTANTS FOR THE SUBSTITUTED PORPHYRIN-LIKE MACROCYCLE
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作者 Shi Ming DONG Duo Yuan WANG Institute of Photographic Chemistry,Academia Sinica,Beijing 100101 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第3期243-246,共4页
The properties of absorption spectra are presented and the linear correlations of Hammett constants with the 0-0 transition energy(E_(o,o))of S_←S_o, and the ratios of oscillator strength(f/f)are used to probe the in... The properties of absorption spectra are presented and the linear correlations of Hammett constants with the 0-0 transition energy(E_(o,o))of S_←S_o, and the ratios of oscillator strength(f/f)are used to probe the interactions betwee π-electron of aromatic maerocycles or metal ion of complexes with the sub- stituents on β-position of benzene ring for porphyrin-like maerocyclic compounds. 展开更多
关键词 TXP Cd CI THE LINEAR CORRELATIONS BETWEEN ELECTRONIC transition energy AND HAMMETT CONSTANTS FOR THE SUBSTITUTED PORPHYRIN-LIKE MACROCYCLE
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Gleaning insights from German energy transition and large-scale underground energy storage for China’s carbon neutrality 被引量:5
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作者 Yachen Xie Xuning Wu +6 位作者 Zhengmeng Hou Zaoyuan Li Jiashun Luo Christian Truitt Lüddeke Liangchao Huang Lin Wu Jianxing Liao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第5期529-553,共25页
The global energy transition is a widespread phenomenon that requires international exchange of experiences and mutual learning.Germany’s success in its first phase of energy transition can be attributed to its adopt... The global energy transition is a widespread phenomenon that requires international exchange of experiences and mutual learning.Germany’s success in its first phase of energy transition can be attributed to its adoption of smart energy technology and implementation of electricity futures and spot marketization,which enabled the achievement of multiple energy spatial–temporal complementarities and overall grid balance through energy conversion and reconversion technologies.While China can draw from Germany’s experience to inform its own energy transition efforts,its 11-fold higher annual electricity consumption requires a distinct approach.We recommend a clean energy system based on smart sector coupling(ENSYSCO)as a suitable pathway for achieving sustainable energy in China,given that renewable energy is expected to guarantee 85%of China’s energy production by 2060,requiring significant future electricity storage capacity.Nonetheless,renewable energy storage remains a significant challenge.We propose four large-scale underground energy storage methods based on ENSYSCO to address this challenge,while considering China’s national conditions.These proposals have culminated in pilot projects for large-scale underground energy storage in China,which we believe is a necessary choice for achieving carbon neutrality in China and enabling efficient and safe grid integration of renewable energy within the framework of ENSYSCO. 展开更多
关键词 Carbon neutrality energy transition Large-scale underground energy storage Sector coupling
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Characteristics of PM_(2.5) and Its Reactive Oxygen Species in Heating Energy Transition and Estimation of Its Impact on the Environment and Health in China——A Case Study in the Fenwei Plain
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作者 Zexuan WANG Hongmei XU +10 位作者 Rong FENG Yunxuan GU Jian SUN Suixin LIU Ningning ZHANG Dan LI Tao WANG Linli QU Steven Sai Hang HO Zhenxing SHEN Junji CAO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第7期1175-1186,共12页
To reduce the adverse effects of traditional domestic solid fuel,the central government began implementing a clean heating policy in northern China in 2017.Clean coal is an alternative low-cost fuel for rural househol... To reduce the adverse effects of traditional domestic solid fuel,the central government began implementing a clean heating policy in northern China in 2017.Clean coal is an alternative low-cost fuel for rural households at the present stage.In this study,18 households that used lump coal,biomass,and clean coal as the main fuel were selected to evaluate the benefits of clean heating transformation in Tongchuan,an energy city in the Fenwei Plain,China.Both indoor and personal exposure(PE)samples of fine particulate matter(PM_(2.5))were synchronically collected.Compared with the lump coal and biomass groups,the indoor PM_(2.5)concentration in the clean coal group is 43.6%and 20.0%lower,respectively,while the values are 16.8%and 21.3%lower,respectively,in the personal exposure samples.PM_(2.5)-bound elements Cd,Ni,Zn,and Mn strongly correlated with reactive oxygen species(ROS)levels in all fuel groups,indicating that transition metals are the principal components to generate oxidative stress.Using a reliable estimation method,it is predicted that after the substitution of clean coal as a household fuel,the all-cause,cardiovascular,and respiratory disease that causes female deaths per year could be reduced by 16,6,and 3,respectively,in the lump coal group,and 22,8,and 3,respectively,in the biomass group.Even though the promotion of clean coal has led to impressive environmental and health benefits,the efficiencies are still limited.More environmental-friendly energy sources must be promoted in the rural regions of China. 展开更多
关键词 clean energy transition solid fuel combustion PM_(2.5) ROS Fenwei Plain
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China’s Energy Transition Pathway in a Carbon Neutral Vision 被引量:10
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作者 Shu Zhang Wenying Chen 《Engineering》 SCIE EI CAS 2022年第7期64-76,共13页
China’s energy system requires a thorough transformation to achieve carbon neutrality.Here,leveraging the highly acclaimed the Integrated MARKAL-EFOM System model of China(China TIMES)that takes energy,the environmen... China’s energy system requires a thorough transformation to achieve carbon neutrality.Here,leveraging the highly acclaimed the Integrated MARKAL-EFOM System model of China(China TIMES)that takes energy,the environment,and the economy into consideration,four carbon-neutral scenarios are proposed and compared for different emission peak times and carbon emissions in 2050.The results show that China’s carbon emissions will peak at 10.3–10.4 Gt between 2025 and 2030.In 2050,renewables will account for 60%of total energy consumption(calorific value calculation)and 90%of total electricity generation,and the electrification rate will be close to 60%.The energy transition will bring sustained air quality improvement,with an 85%reduction in local air pollutants in 2050 compared with 2020 levels,and an early emission peak will yield more near-term benefits.Early peak attainment requires the extensive deployment of renewables over the next decade and an accelerated phasing out of coal after 2025.However,it will bring benefits such as obtaining better air quality sooner,reducing cumulative CO_(2) emissions,and buying more time for other sectors to transition.The pressure for more ambitious emission reductions in 2050 can be transmitted to the near future,affecting renewable energy development,energy service demand,and welfare losses. 展开更多
关键词 Carbon neutrality energy transition Climate change mitigation China TIMES model Synergistic effects
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The role of capital deepening in China's energy transition
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作者 Dong Wang Yixiao Zhou +1 位作者 Jian Ding Wanjia Wang 《Chinese Journal of Population,Resources and Environment》 2019年第3期197-202,共6页
This paper provides a theoretical model to explain the causality between China's energy transition and capital deepening found by the empirical study.We prove that in the equilibrium,China's energy transition ... This paper provides a theoretical model to explain the causality between China's energy transition and capital deepening found by the empirical study.We prove that in the equilibrium,China's energy transition is endogenously determined by capital deepening due to the homogeneity of electricity and the monopolistic competition features of China's electricity market.Price effect,which is the effect of change in relative factor price,will affect energy transition only if the policy intervenes electricity price in terms of the primary sources from which it is generated.We propose that investment can promote energy transition by stimulating capital deepening which is biased to clean energy development.In this regard,our paper provides a new way of thinking for other developing countries to design an effective energy transition policy. 展开更多
关键词 energy transition capital deepening China electricity market
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Quanta of the Phase-Space Areas Given by Intervals of Energy and Time Associated with Electron Transitions
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作者 Stanislaw Olszewski 《Journal of Modern Physics》 2017年第8期1158-1174,共17页
The paper examines the energy of electron transitions in an emission process and the time intervals necessary for that process. For simple quantum systems, the both parameters—that of energy and time—depend on the d... The paper examines the energy of electron transitions in an emission process and the time intervals necessary for that process. For simple quantum systems, the both parameters—that of energy and time—depend on the difference &Delta;n of the quantum numbers n labelling the beginning and end state of emission. It is shown that the phase-space areas formed by products of energy and time involved in the emission can be represented as a quadratic function of &Delta;n multiplied by the Planck constant h. 展开更多
关键词 Electron transitions Their Energies and transition Times Quanta of the Phase-Space Areas of energy and Time
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On the Seasonal Transition and the Interannual Variability in Global Kinetic Energy at 500 hPa, Accompanied withAnomalies of Energy during the 1982 / 83 ENSO
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作者 仇永炎 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1993年第2期248-256,共9页
Utilizing the material of monthly means of the three primary kinetic energy modes over the whote globe at 500 hPa during the nine years of 1980-1988, both the rapid seasonal changes and the interannual variability in ... Utilizing the material of monthly means of the three primary kinetic energy modes over the whote globe at 500 hPa during the nine years of 1980-1988, both the rapid seasonal changes and the interannual variability in tie general circulation in terms of the energy modes have been investigated, with special attention paid to the unusual year 1983, Two main results are obtained. One, there are remarkable seasonal rapid changes over the Northern Hemisphere, occurring ganerally in April and October. The other, among the nine years of 1980-1988, 1983 is the only one with unusual energy modes and remarkably abnormal seasonal changes. 展开更多
关键词 Accompanied withAnomalies of energy during the 1982 On the Seasonal transition and the Interannual Variability in Global Kinetic energy at 500 hPa SSTA ENSO
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A Synthesis of Energy Transition Policies in Finland and China
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作者 GUO Wen PAN Jiaofeng +2 位作者 LIANG Liting Jari KUUSISTO MA Yanran 《Bulletin of the Chinese Academy of Sciences》 2022年第1期40-44,共5页
Since 2017,Finland and China have been developing a future-oriented partnership based on mutual economic and business interests.The starting point for this work is the recognition of significant differences in size,cu... Since 2017,Finland and China have been developing a future-oriented partnership based on mutual economic and business interests.The starting point for this work is the recognition of significant differences in size,culture,and political as well as economic systems between the two sides.The Sino-Finnish cooperation in energy transition can provide a good example of mutually beneficial partnership where countries complement each other in terms of knowhow and resources.This paper brings together the main findings from the policy study on energy transition in Finland and China.It aims to identify potential policy initiatives for expanding Sino-Finnish cooperation towards green growth. 展开更多
关键词 energy transition POLICY Sino-Finnish Cooperation
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Fiscal and Tax Policy Research on Promoting Energy Transition in China under the"Dual Carbon"Goal
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作者 Yaxue Wei 《管理科学与研究(中英文版)》 2022年第7期60-65,共6页
The"Dual Carbon"Goal is one of the critical strategic tasks in China's new stage of development,and fiscal and tax policies play an essential role in promoting the"dual carbon target"process.Cu... The"Dual Carbon"Goal is one of the critical strategic tasks in China's new stage of development,and fiscal and tax policies play an essential role in promoting the"dual carbon target"process.Currently,China's fiscal and taxation policies to encourage the realization of the"dual carbon"target are faced with problems such as the lack of budgetary and tax regulation means and the lack of investment in the energy conservation industry.Throughout the mature experience of Britain,the United States,Japan,and other countries,although different,they all chose to levy carbon tax and tax incentives as the path to promote energy transformation.To further encourage energy conversion,China can choose to establish a carbon tax mechanism and promote and improve low-carbon preferential policies and other diversified fiscal and tax policies. 展开更多
关键词 “Dual Carbon”Goal energy transition Foreign Practice The Fiscal and Taxation Policy
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Relativistic Reduction of the Electron-Nucleus Force in Bohr’s Hydrogen Atom and the Time of Electron Transition between the Neighbouring Quantum Energy Levels
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作者 Stanisław Olszewski 《Journal of Modern Physics》 2020年第6期944-951,共8页
The aim of the paper is to get an insight into the time interval of electron emission done between two neighbouring energy levels of the hydrogen atom. To this purpose, in the first step, the formulae of the special r... The aim of the paper is to get an insight into the time interval of electron emission done between two neighbouring energy levels of the hydrogen atom. To this purpose, in the first step, the formulae of the special relativity are applied to demonstrate the conditions which can annihilate the electrostatic force acting between the nucleus and electron in the atom. This result is obtained when a suitable electron speed entering the Lorentz transformation is combined with the strength of the magnetic field acting normally to the electron orbit in the atom. In the next step, the Maxwell equation characterizing the electromotive force is applied to calculate the time interval connected with the change of the magnetic field necessary to produce the force. It is shown that the time interval obtained from the Maxwell equation, multiplied by the energy change of two neighbouring energy levels considered in the atom, does satisfy the Joule-Lenz formula associated with the quantum electron energy emission rate between the levels. 展开更多
关键词 Hydrogen Atom The Bohr Model Lorentz Transformation Done with the Aid of the Electron Orbital Speed Maxwell Equation Applied to Calculate the Time Interval of Electron transitions between Two Quantum energy Levels Comparison with the Joule-Lenz Law for energy Emission
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Photoluminescence Properties and Energy Transfer from Ce^(3+) to Tb^(3+) in Zn_2SiO-_4 Host 被引量:1
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作者 熊晓波 袁曦明 +3 位作者 LIANG Yujun SONG Jiangqi WU Qi YIN Guoxiang 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2015年第2期235-240,共6页
Zn2Si O4︰Tb^3+, Zn2 Si O4︰Ce^3+, Zn2 Si O4︰Tb^3+, Ce^3+ phosphors were prepared by solidstate reaction at 1 150 ℃ for 2h under a weak reducing atmosphere. Moreover, the XRD patterns and photoluminescence spect... Zn2Si O4︰Tb^3+, Zn2 Si O4︰Ce^3+, Zn2 Si O4︰Tb^3+, Ce^3+ phosphors were prepared by solidstate reaction at 1 150 ℃ for 2h under a weak reducing atmosphere. Moreover, the XRD patterns and photoluminescence spectra were recorded and the effects of Tb3+ and Ce3+ concentration on the luminescent properties of as-synthesized phosphors were investigated. The emission spectra under ultraviolet light(333 nm) radiation showed a dominant peak at 542 nm attributed to the 5D4→7F5 transition of Tb^3+, which was enhanced significantly(about 45 times) by the co-doping of Ce^3+, indicating that there occurred an efficient energy transfer from Ce^3+ to Tb^3+. According to the Dexter's energy transfer formula of multipolar interaction, it was demonstrated that the energy transfer between Ce3+ and Tb3+ was due to the electric dipolar-dipolar interaction of the resonance transfer. 展开更多
关键词 phosphors emission Zn2SiO4:Tb^3+ Ce^3+ transition energy transfer
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Numerical Verification of Transition’s Energies of Excitons in Quantum Well of ZnO with the Finite Difference Method
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作者 Bassirou Lô Serigne Bira Gueye 《Journal of Modern Physics》 2016年第3期329-334,共6页
This paper shows that the experimental results of quantum well energy transitions can be found numerically. The cases of several ZnO-ZnMgO wells are considered and their excitonic transition energies were calculated u... This paper shows that the experimental results of quantum well energy transitions can be found numerically. The cases of several ZnO-ZnMgO wells are considered and their excitonic transition energies were calculated using the finite difference method. In that way, the one-dimensional Schrödinger equation has been solved by using the BLAS and LAPACK libraries. The numerical results are in good agreement with the experimental ones. 展开更多
关键词 Quantum Well ZnO-ZnMgO Finite Difference Method EXCITON transition energy
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Integration of a nonlinear energy sink and a piezoelectric energy harvester 被引量:6
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作者 Xiang LI Yewei ZHANG +1 位作者 Hu DING Liqun CHEN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第7期1019-1030,共12页
A mechanical-piezoelectric system is explored to reduce vibration and to harvest energy. The system consists of a piezoelectric device and a nonlinear energy sink (NES), which is a nonlinear oscillator without linea... A mechanical-piezoelectric system is explored to reduce vibration and to harvest energy. The system consists of a piezoelectric device and a nonlinear energy sink (NES), which is a nonlinear oscillator without linear stiffness. The NES-piezoelectric sys- tem is attached to a 2-degree-of-freedom primary system subjected to a shock load. This mechanical-piezoelectric system is investigated based on the concepts of the percentages of energy transition and energy transition measure. The strong target energy transfer occurs for some certain transient excitation amplitude and NES nonlinear stiffness. The plots of wavelet transforms are used to indicate that the nonlinear beats initiate energy transitions between the NES-piezoelectric system and the primary system in the tran- sient vibration, and a 1:1 transient resonance capture occurs between two subsystems. The investigation demonstrates that the integrated NES-piezoelectric mechanism can re- duce vibration and harvest some vibration energy. 展开更多
关键词 nonlinear energy sink (NES) nonlinear beat phenomenon piezoelectricenergy harvester energy transition NES-piezoelectric system
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Theoretical study on K,L,and M X-ray transition energies and rates of neptunium and its ions 被引量:1
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作者 Ismail Abdalla Saber 董晨钟 +2 位作者 王向丽 周卫东 武中文 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第2期193-198,共6页
The transition energies and electric dipole (El) transition rates of the K, L, and M lines in neutral Np have been theoretically determined from the MultiConfiguration Dirac-Fock (MCDF) method. In the calculations... The transition energies and electric dipole (El) transition rates of the K, L, and M lines in neutral Np have been theoretically determined from the MultiConfiguration Dirac-Fock (MCDF) method. In the calculations, the contributions from Breit interaction and quantum electrodynamics (QED) effects (vacuum polarization and self-energy), as well as nu- clear finite mass and volume effects, are taken into account. The calculated transition energies and rates are found to be in good agreement with other experimental and theoretical results. The accuracy of the results is estimated and discussed. Furthermore, we calculated the transition energies of the same lines radiating from the decaying transitions of the K-, L-, and M-shell hole states of Np ions with the charge states Np1+ to Np6+ for the first time. We found that for a specific line, the corresponding transition energies relating to all the Np ions are almost the same; it means the outermost electrons have a very small influence on the inner-shell transition processes. 展开更多
关键词 Np ions K L and M X-rays transition energies transition rates
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Relativistic calculations of 3s^2 ~1S_0-3s3p ~1P_1 and 3s^2 ~1S_0-3s3p ~3P_(1,2) transition probabilities in the Mg isoelectronic sequence 被引量:1
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作者 程诚 高翔 +2 位作者 青波 张小乐 李家明 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第3期150-156,共7页
Using the multi-configuration Dirac-Fock self-consistent field method and the relativistic configuration-interaction method, calculations of transition energies, oscillator strengths and rates are performed for the 3s... Using the multi-configuration Dirac-Fock self-consistent field method and the relativistic configuration-interaction method, calculations of transition energies, oscillator strengths and rates are performed for the 3s2 1S0-3s3p 1P1 spinallowed transition, 3s2 1S0-3s3p 3P1,2 intercombination and magnetic quadrupole transition in the Mg isoelectronic sequence (Mg I, A1 II, Si III, P IV and S V). Electron correlations are treated adequately, including intravalence electron correlations. The influence of the Breit interaction on oscillator strengths and transition energies are investigated. Quantum eleetrodynamics corrections are added as corrections. The calculation results are found to be in good agreement with the experimental data and other theoretical calculations. 展开更多
关键词 transition energies oscillator strengths relativistic calculation Breit interactions
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Fault on-off versus strain rate and earthquakes energy 被引量:4
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作者 C.Doglioni S.Barba +1 位作者 E.Carminati F.Riguzzi 《Geoscience Frontiers》 SCIE CAS CSCD 2015年第2期265-276,共12页
We propose that the brittle-ductile transition (BDT) controls the seismic cycle. In particular, the movements detected by space geodesy record the steady state deformation in the ductile lower crust, whereas the sti... We propose that the brittle-ductile transition (BDT) controls the seismic cycle. In particular, the movements detected by space geodesy record the steady state deformation in the ductile lower crust, whereas the stick-slip behavior of the brittle upper crust is constrained by its larger friction. GPS data allow analyzing the strain rate along active plate boundaries. In all tectonic settings, we propose that earthquakes primarily occur along active fault segments characterized by relative minima of strain rate, segments which are locked or slowly creeping. We discuss regional examples where large earthquakes happened in areas of relative low strain rate. Regardless the tectonic style, the interseismic stress and strain pattern inverts during the coseismic stage. Where a dilated band formed during the interseismic stage, this will be shortened at the coseismic stage, and vice-versa what was previously shortened, it will be dilated. The interseismic energy accumulation and the coseismic expenditure rather depend on the tectonic setting (extensional, contractional, or strike-slip). The gravitational potential energy dominates along normal faults, whereas the elastic energy prevails for thrust earthquakes and performs work against the gravity force. The energy budget in strike-slip tectonic setting is also primarily due elastic energy. Therefore, precursors may be different as a function of the tectonic setting. In this model, with a given displacement, the magnitude of an earthquake results from the coseismic slip of the deformed volume above the BDT rather than only on the fault length, and it also depends on the fault kinematics. 展开更多
关键词 Earthquake generation mode Strain rate Brittle-ductile transition Earthquake energy
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Synergies of carbon neutrality, air pollution control, and health improvement - a case study of China Energy Interconnection scenario 被引量:1
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作者 Jianxiang Shen Wenjia Cai +5 位作者 Xiaotong Chen Xing Chen Zijian Zhao Zhiyuan Ma Fang Yang Shaohui Zhang 《Global Energy Interconnection》 EI CAS CSCD 2022年第5期531-542,共12页
Climate change and air pollution are primarily caused by the combustion and utilization of fossil fuels.Both climate change and air pollution cause health problems.Based on the development of China,it is extremely imp... Climate change and air pollution are primarily caused by the combustion and utilization of fossil fuels.Both climate change and air pollution cause health problems.Based on the development of China,it is extremely important to explore the synergies of the energy transition,CO_(2) reduction,air pollution control,and health improvement under the target of carbon peaking before 2030 and carbon neutrality before 2060.This study introduces the policy evolution and research progress related to energy,climate change,and the environment in China and proposes a complete energy-climate-air-health mechanism framework.Based on the MESSAGE-GLOBIOM integrated assessment model,emission inventory and chemical transport model,and exposure-response function,a comprehensive assessment method of energy-climate-air-health synergies was established and applied to quantify the impacts of Chinese Energy Interconnection Carbon Neutrality(CEICN)scenario.The results demonstrate that,by 2060,the SO_(2),NO_(x) and PM_(2.5) emissions are estimated to be reduced by 91%,85%,and 90%respectively compared to the business-as-usual(BAU)scenario.The direct health impacts brought by achieving the goal of carbon neutrality will drive the proactive implementation of more emission reduction measures and bring greater benefits to human health. 展开更多
关键词 energy-climate-air-health synergies Climate change energy transition Carbon neutrality China energy Interconnection.
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Supplemental Smartamine M in higher-energy diets during the prepartal period improves hepatic biomarkers of health and oxidative status in Holstein cows 被引量:3
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作者 Mario Vailati-Riboni Johan S.Osorio +2 位作者 Erminio Trevisi Daniel Luchini Juan J.Loor 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2017年第3期624-635,共12页
Background: Feeding higher-energy prepartum is a common practice in the dairy industry. However, recent data underscore how it could reduce performance, deepen negative energy balance, and augment inflammation and ox... Background: Feeding higher-energy prepartum is a common practice in the dairy industry. However, recent data underscore how it could reduce performance, deepen negative energy balance, and augment inflammation and oxidative stress in fresh cows. We tested the effectiveness of rumen-protected methionine in preventing the negative effect of feeding a higher-energy prepartum. Multiparous Holstein cows were fed a control lower-energy diet(CON, 1.24 Mcal/kg DM; high-straw) during the whole dry period(-50 d), or were switched to a higher-energy(OVE, 1.54 Mcal/kg DM), or OVE plus Smartamine M(OVE + SM; Adisseo NA) during the last 21 d before calving.Afterwards cows received the same lactation diet(1.75 Mcal/kg DM). Smartamine M was top-dressed on the OVE diet(0.07% of DM) from -21 through 30 d in milk(DIM). Liver samples were obtained via percutaneous biopsy at -10, 7 and 21 DIM. Expression of genes associated with energy and lipid metabolism, hepatokines, methionine cycle, antioxidant capacity and inflammation was measured.Results: Postpartal dry matter intake, milk yield, and energy-corrected milk were higher in CON and OVE + SM compared with OVE. Furthermore, milk protein and fat percentages were greater in OVE + SM compared with CON and OVE. Expression of the gluconeogenic gene PCK1 and the lipid-metabolism transcription regulator PPARA was again greater with CON and OVE + SM compared with OVE. Expression of the lipoprotein synthesis enzyme MTTP was lower in OVE + SM than CON or OVE. Similarly, the hepatokine FGF21, which correlates with severity of negative energy balance, was increased postpartum only in OVE compared to the other two groups. These results indicate greater liver metabolism and functions to support a greater production in OVE + SM. At 7 DIM, the enzyme GSR involved in the synthesis of glutathione tended to be upregulated in OVE than CON-fed cows, suggesting a greater antioxidant demand in overfed cows. Feeding OVE + SM resulted in lower similar expression of GSR compared with CON. Expression of the methionine cycle enzymes SAHH and MTR, both of which help synthesize methionine endogenously, was greater prepartum in OVE + SM compared with both CON and OVE, and at 7 DIM for CON and OVE + SM compared with OVE, suggesting greater Met availability. It is noteworthy that DNMT3A, which utilizes S-adenosylmethionine generated in the methionine cycle, was greater in OVE and OVE + SM indicating higher-energy diets might enhance DNA methylation, thus, Met utilization.Conclusions: Data indicate that supplemental Smartamine M was able to compensate for the negative effect of prepartal energy-overfeeding by alleviating the demand for intracellular antioxidants, thus, contributing to the increase in production. Moreover Smartamine M improved hepatic lipid and glucose metabolism, leading to greater liver function and better overall health. 展开更多
关键词 energy Methionine Nutrigenomics transition period
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Transition parameters of Li-like ions(Z=7-11)in dense plasmas
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作者 李向富 贾利平 +1 位作者 王宏斌 蒋刚 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第5期328-337,共10页
The energy levels,transition energies,transition probabilities,weighted oscillator strengths,and line strengths of Li-like ions(Z=7-11)in dense plasmas are investigated in this work.The relativistic effects and electr... The energy levels,transition energies,transition probabilities,weighted oscillator strengths,and line strengths of Li-like ions(Z=7-11)in dense plasmas are investigated in this work.The relativistic effects and electron correlation effects are described by the MCDHF method.The ion sphere model is applied to include the dense plasma screening effect.The ground configuration 1s^(2)2s and the excited 1s^(2)2p,1s^(2)3l(l=0-2)are considered.The configuration sets are enlarged until n=7 where the calculated energy levels have converged.The critical free electron densities of 1s^(2)3d states are estimated.Except for 1s^(2)3s-1s^(2)3p transitions,the transition energies for△n=0 increase,and for△n≠0 decrease with increasing free electron densities.For 1s^(2)3s-1s^(2)3p transitions,the spectra show blue-shift at lower free electron densities and red-shift at higher free electron densities,and the energy level crossing phenomens are observed at higher free electron densities. 展开更多
关键词 Li-like ions energy levels transition energies transition probabilities
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