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Effects of 4f Electron Characteristics and Alternation Valence of Rare Earths on Photosynthesis: Regulating Distribution of Energy and Activities of Spinach Chloroplast 被引量:7
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作者 刘晓晴 苏明玉 +3 位作者 刘超 张易 司文会 洪法水 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第4期495-501,共7页
Chloroplasts were isolated from spinach treated with taCl3, CeCl3, and NdCl3. Because of owning 4f electron characteristics and alternation valence, Ce treatment presented the highest enhancement in light absorption, ... Chloroplasts were isolated from spinach treated with taCl3, CeCl3, and NdCl3. Because of owning 4f electron characteristics and alternation valence, Ce treatment presented the highest enhancement in light absorption, energy transfer from LHC Ⅱ to PS Ⅱ, excitation energy distribution from PS Ⅰ to PS Ⅱ, and fluorescence quantum yield around 680 nm. Compared with Ce treatment, Nd treatment resulted in relatively lower enhancement in these physiological indices, as Nd did not have alternation valence. La treatment presented the lowest enhancement, as La did not have either 4f electron or alternation valence. The increase in activities of whole chain electron transport, PS ⅡDCPIP photoreduction, and oxygen evolution of chloroplasts was of the following order: Ce〉Nd 〉La〉 control. However, the photoreduction activities of spinach PS I almost did not change with La, Ce, or Nd treatments. The results suggested that 4f electron characteristics and alternation valence of rare earths had a close relationship with photosynthesis improvement. 展开更多
关键词 4f electron characteristic and alternation valence SPINACH CHLOROPLAST energy transfer and distribution photochemical activity rare earths
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A code-independent technique for computational verification of fluid mechanics and heat transfer problems
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作者 M.Garbey C.Picard 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2008年第4期387-397,共11页
The goal of this paper is to present a versatile framework for solution verification of PDE's. We first generalize the Richardson Extrapolation technique to an optimized extrapolation solution procedure that construc... The goal of this paper is to present a versatile framework for solution verification of PDE's. We first generalize the Richardson Extrapolation technique to an optimized extrapolation solution procedure that constructs the best consistent solution from a set of two or three coarse grid solution in the discrete norm of choice. This technique generalizes the Least Square Extrapolation method introduced by one of the author and W. Shyy. We second establish the conditioning number of the problem in a reduced space that approximates the main feature of the numerical solution thanks to a sensitivity analysis. Overall our method produces an a posteriori error estimation in this reduced space of approximation. The key feature of our method is that our construction does not require an internal knowledge of the software neither the source code that produces the solution to be verified. It can be applied in principle as a postprocessing procedure to off the shelf commercial code. We demonstrate the robustness of our method with two steady problems that are separately an incompressible back step flow test case and a heat transfer problem for a battery. Our error estimate might be ultimately verified with a near by manufactured solution. While our pro- cedure is systematic and requires numerous computation of residuals, one can take advantage of distributed computing to get quickly the error estimate. 展开更多
关键词 Solution verification PDE's Navier Stokes ·Heat transfer. Aposteriori estimate·Distributed Computing
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Effects of thermal transport properties on temperature distribution within silicon wafer
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作者 王爱华 牛义红 +1 位作者 陈铁军 P.F.HSU 《Journal of Central South University》 SCIE EI CAS 2014年第4期1402-1410,共9页
A combined conduction and radiation heat transfer model was used to simulate the heat transfer within wafer and investigate the effect of thermal transport properties on temperature non-uniformity within wafer surface... A combined conduction and radiation heat transfer model was used to simulate the heat transfer within wafer and investigate the effect of thermal transport properties on temperature non-uniformity within wafer surface. It is found that the increased conductivities in both doped and undoped regions help reduce the temperature difference across the wafer surface. However, the doped layer conductivity has little effect on the overall temperature distribution and difference. The temperature level and difference on the top surface drop suddenly when absorption coefficient changes from 104 to 103 m-1. When the absorption coefficient is less or equal to 103 m-1, the temperature level and difference do not change much. The emissivity has the dominant effect on the top surface temperature level and difference. Higher surface emissivity can easily increase the temperature level of the wafer surface. After using the improved property data, the overall temperature level reduces by about 200 K from the basis case. The results will help improve the current understanding of the energy transport in the rapid thermal processing and the wafer temperature monitor and control level. 展开更多
关键词 silicon wafer thermal transport properties temperature distribution radiation heat transfer
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Computational analysis of the flow of pseudoplastic power-law fluids in a microchannel plate 被引量:2
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作者 Saeed Mortazavi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第10期1360-1368,共9页
The flow of pseudoplastic power-law fluids with different flow indexes at a microchannel plate was studied using computational fluid dynamic simulation.The velocity distribution along the microchannel plate and especi... The flow of pseudoplastic power-law fluids with different flow indexes at a microchannel plate was studied using computational fluid dynamic simulation.The velocity distribution along the microchannel plate and especially in the microchannel slits,flow pattern along the outlet arc and the pressure drop through the whole of microchannel plate were investigated at different power-law flow indexes.The results showed that the velocity profile in the microchannel slits for low flow index fluids was similar to the plug flow and had uniform pattern.Also the power-law fluids with lower flow indexes had lower stagnation zones near the outlet of the microchannel plate.The pressure drop through the microchannel plate showed huge differences between the fluids.The most interesting result was that the pressure drops for power-law fluids were very smaller than that of Newtonian fluids.In addition,the heat transfer of the fluids through the microchannel with different channel numbers in a wide range of Reynolds number was investigated.For power-law fluid with flow index(n=0.4),the Nusselt number increases continuously as the number of channels increases.The results highlight the potential use of using pseudoplastic fluids in the microheat exchangers which can lower the pressure drop and increase the heat transfer efficiency. 展开更多
关键词 Power-law fluids Microchannel Pressure drop Flow distribution Heat transfer
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Chain Rule for Extracting Resilience Procurement Costs from Locational Marginal Prices
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作者 Yifei Wang Tong Zhu +2 位作者 Tiancong Chen Mohammad Shahidehpour Qingshan Xu 《CSEE Journal of Power and Energy Systems》 SCIE EI CSCD 2024年第3期1342-1355,共14页
Power system resilience procurement costs in N-k contingencies have gained more prominence as number of extreme events continues to increase.A chain rule is presented in this paper for extracting resilience procuremen... Power system resilience procurement costs in N-k contingencies have gained more prominence as number of extreme events continues to increase.A chain rule is presented in this paper for extracting resilience procurement costs from a fully decomposed locational marginal price(LMP)model.First,power transfer distribution factor(PTDF)matrices with AC power flow(i.e.,AC-PTDF)are determined.AC-PTDF and AC-LODF(line outage distribution factor)equations are derived for N-k contingencies and a fully decomposed LMP model is developed where generation and transmission security components are established for specific contingencies.Furthermore,resilience procurement costs can be measured at different buses for the proposed security components.Impact of N-k contingencies on resilience procurement costs at specific buses can be determined as proposed security components will gain more insight for resilience procurement in power systems.The modified IEEE 6-bus and 118-bus systems are adopted to verify effectiveness of the proposed resilience procurement method. 展开更多
关键词 Line outage distribution factors locational marginal price power system resilience power transfer distribution factor security components
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Structural dynamic responses of a stripped solar sail subjected to solar radiation pressure 被引量:6
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作者 Junhui ZHANG Na WU +1 位作者 An TONG Yinghua LIU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2020年第8期2204-2211,共8页
The stripped solar sail whose membrane is divided into separate narrow membrane strips is believed to have the best structural efficiency.In this paper,the stripped solar sail structure is regarded as an assembly made... The stripped solar sail whose membrane is divided into separate narrow membrane strips is believed to have the best structural efficiency.In this paper,the stripped solar sail structure is regarded as an assembly made by connecting a number of boom-strip components in sequence.Considering the coupling effects between booms and membrane strips,an exact and semianalytical method to calculate structural dynamic responses of the stripped solar sail subjected to solar radiation pressure is established.The case study of a 100 m stripped solar sail shows that the stripped architecture helps to reduce the static deflections and amplitudes of the steady-state dynamic response.Larger prestress of the membrane strips will decrease stiffness of the sail and increase amplitudes of the steady-state dynamic response.Increasing thickness of the boom will benefit to stability of the sail and reduce the resonant amplitudes.This proposed semi-analytical method provides an efficient analysis tool for structure design and attitude control of the stripped solar sail. 展开更多
关键词 Distributed transfer function method Frequency response Solar radiation pressure Solar sail Structural dynamic response
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Knowledge Graph Embedding for Hyper-Relational Data 被引量:7
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作者 Chunhong Zhang Miao Zhou +2 位作者 Xiao Han Zheng Hu Yang Ji 《Tsinghua Science and Technology》 SCIE EI CAS CSCD 2017年第2期185-197,共13页
Knowledge graph representation has been a long standing goal of artificial intelligence. In this paper,we consider a method for knowledge graph embedding of hyper-relational data, which are commonly found in knowledge... Knowledge graph representation has been a long standing goal of artificial intelligence. In this paper,we consider a method for knowledge graph embedding of hyper-relational data, which are commonly found in knowledge graphs. Previous models such as Trans(E, H, R) and CTrans R are either insufficient for embedding hyper-relational data or focus on projecting an entity into multiple embeddings, which might not be effective for generalization nor accurately reflect real knowledge. To overcome these issues, we propose the novel model Trans HR, which transforms the hyper-relations in a pair of entities into an individual vector, serving as a translation between them. We experimentally evaluate our model on two typical tasks—link prediction and triple classification.The results demonstrate that Trans HR significantly outperforms Trans(E, H, R) and CTrans R, especially for hyperrelational data. 展开更多
关键词 distributed representation transfer matrix knowledge graph embedding
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Theoretical study of fusion reactions ^(32)S + ^(94,96)Zr and ^(40)Ca + ^(94,96)Zr and quadrupole deformation of ^(94)Zr
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作者 Bing Wang WeiJuan Zhao +1 位作者 EnGuang Zhao ShanGui Zhou 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2016年第4期58-65,共8页
The dynamic coupling effects on fusion cross sections for reactions^(32)S + ^(94,96)Zr and ^(40)Ca + ^(94,96)Zr are studied with the universal fusion function formalism and an empirical coupled channel(ECC) model. An ... The dynamic coupling effects on fusion cross sections for reactions^(32)S + ^(94,96)Zr and ^(40)Ca + ^(94,96)Zr are studied with the universal fusion function formalism and an empirical coupled channel(ECC) model. An examination of the reduced fusion functions shows that the total effect of couplings to inelastic excitations and neutron transfer channels on fusion in ^(32)S +^(94)Zr(^(40)Ca +^(94)Zr) is almost the same as that in ^(32)S +^(96)Zr(^(40)Ca +^(96)Zr). The enhancements of the fusion cross section at sub-barrier energies due to inelastic channel coupling and neutron transfer channel coupling are evaluated separately by using the ECC model. The results show that effect of couplings to inelastic excitations channels in the reactions with94 Zr as target should be similar as that in the reactions with ^(96) Zr as target. This implies that the quadrupole deformation parameters β_2of ^(94)Zr and^(96) Zr should be similar to each other.However, β_2 's predicted from the finite-range droplet model, which are used in the ECC model, are quite different. Experiments on^(48) Ca +^(94)Zr or^(36) S +^(94)Zr are suggested to solve the puzzling issue concerning β_2for^(94)Zr. 展开更多
关键词 empirical coupled channel model barrier distribution universal fusion function neutron transfer
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