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Mirror Stage Theory Analysis of Bravery in Zootopia(2016)and Nezha(2019)
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作者 ZOU Jia-cheng 《Journal of Literature and Art Studies》 2024年第1期40-47,共8页
American Hollywood animated films have conquered the world.In recent years,many successful works have appeared in domestic animated films,bringing new vitality to the Chinese animated film industry.Based on Lacan’s M... American Hollywood animated films have conquered the world.In recent years,many successful works have appeared in domestic animated films,bringing new vitality to the Chinese animated film industry.Based on Lacan’s Mirror Stage Theory,this study attempts to start from the bravery of Judy and Nezha,the protagonists of Zootopia(2016)and Nezha(2019).It analyzes and compares their embodiment,formation,influence and reflection with real society to solve the problems of the two brave characters’formation causes,characteristic differences and social influences,including racial discrimination,individualism in American society and family problems in Chinese society.This study sheds light on the transmission of intercultural values in animated films. 展开更多
关键词 Mirror Stage theory Zootopia Nezha:birth of the Demon Child Judy Nezha Bravery
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Quantum and Classical Approach Applied to the Motion of a Celestial Body in the Solar System
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作者 Stanisław Olszewski 《Journal of Modern Physics》 2016年第14期1901-1908,共8页
According to the classical mechanics the energy of a celestial body circulating in the solar system is a constant term. This energy is defined by the masses product of the larger and smaller body entering into a mutua... According to the classical mechanics the energy of a celestial body circulating in the solar system is a constant term. This energy is defined by the masses product of the larger and smaller body entering into a mutual attraction as well as the size of the major semiaxis characteristic for the corresponding Kepler orbit. A special situation concerns the planet interaction with the Sun because of a systematic decrease of the Sun mass due to the luminosity effect. The aim of the paper is to point out that even in the case of perfectly constant interacting masses the energy of the moving body should decrease when a quantum treatment of the body motion is considered. The rate of the energy decrease is extremely small, nevertheless it gives a shortening of the distance between the interacting bodies leading to a final effect of a touch of the larger body and a smaller one. 展开更多
关键词 solar system Classical Mechanics and Quantum theory Emission Rate of Energy by a Moving Planet the Earth Planet Taken as an Example
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Simulation of Vertical Solar Power Plants with Different Turbine Blades
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作者 Yuxing Yang Peng Zhang Meng Lv 《Fluid Dynamics & Materials Processing》 EI 2023年第6期1397-1409,共13页
The performances of turbine blades have a significant impact on the energy conversion efficiency of vertical solar power plants.In the present study,such a relationship is assessed by considering two kinds of airfoil ... The performances of turbine blades have a significant impact on the energy conversion efficiency of vertical solar power plants.In the present study,such a relationship is assessed by considering two kinds of airfoil blades,designed by using the Wilson theory.In particular,numerical simulations are conducted using the SST K−ω model and assuming a wind speed of 3–6 m/s and seven or eight blades.The two airfoils are the NACA63121(with a larger chord length)and the AMES63212;It is shown that the torsion angle of the former is smaller,and its wind drag ratio is larger;furthermore,the resistance is increased by about 66.3%on average.Within the scope of the study,the results show that the NACA63212 airfoil is better than the AMES63212 airfoil in terms of power,with an average improvement of about 2.8%.The simulation results have a certain guiding significance for selecting turbine blade airfoils and improving turbine efficiency. 展开更多
关键词 Vertical solar power plant wilson theory airfoil modification numerical simulation chord length torsion angle
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Acute myocardial infarction (AMI) in context with the paradigm―month of birth and longevity 被引量:1
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作者 Elyiahu Stoupel Abdonas Tamoshiunas +3 位作者 Richardas Radishauskas Gailute Bernotiene Evgeny Abramson Peter Israelevich 《Health》 2011年第12期732-736,共5页
Time and environmental physical activity are involved in timing of many medical events. In a recent study published by the National Academy of Science, USA it was shown that month of birth is related to longevity. The... Time and environmental physical activity are involved in timing of many medical events. In a recent study published by the National Academy of Science, USA it was shown that month of birth is related to longevity. The aim of this study was to check the month of birth distribution in a great group of AMI patients of both gender, one of the great killers in the developed countries, to check the mentioned paradigm of month of birth and longevity. Methods & Patients: Patients admitted to Cardiology Departments of a tertiary University Hospital in Kaunas, Lithuania with AMI at years 1990-2010 (n-22047) were studied. Month of birth of these patients, total and both gender were checked. Monthly, quarterly and trimester comparison were done. Statistical differences established using t-Student test and distribution by percents of the yearly months of birth. Results: It was a significant difference in the month of birth of the studied AMI population. January and first quarter and trimester born patients were more often in the studied AMI patients group. The higher morbidity by Cardiovascular diseases can be a significant ingredient in the structure of population longevity. Possible mechanisms explaining our findings are discussed. Conclusion: In the AMI population people born in January, first quarter or trimester of the year are dominating in both gender groups. The results of this study can be an additional confirmation of the paradigm about links between month of birth and longevity. 展开更多
关键词 Acute Myocardial INFARCTION MONTH birth Men Women solar GEOMAGNETIC Cosmic Ray Activity Nutrition
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Mechanical and Experimental Study of Sprinkling Water Cooling System on Roof of Shanghai Expo Theme Pavilion
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作者 ZHAO Hui-zhong1,HUANG Chen1,LI Wei-xiang2,SHI Jin-yue2,TAO Si-yuan1,WANG Qian1,WANG Yu-qing1,ZHANG Min3(1.College of Urban Construction and Environment Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China 2.Architectural Design & Research Institute of Tongji University,Shanghai 200092,China 3.College of Food Science Technology,Shanghai Ocean University,Shanghai 201306,China) 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2009年第S1期156-159,共4页
Based on the similarity theory,a scale effect model of the spraying water cooling system of Shanghai expo Theme Pavilion's roof was set up.According to the typical weather conditions in Shanghai city,different mod... Based on the similarity theory,a scale effect model of the spraying water cooling system of Shanghai expo Theme Pavilion's roof was set up.According to the typical weather conditions in Shanghai city,different models were analyzed on solar radiation,and different heat transfer amount was obtained.And the following conclusions could be made:At the sunny day of summer in Shanghai,the temperature of inner roof with sprinkling system descended about 3 ℃,and the air conditioning load of the whole Theme Pavilion descend more than 320 kW. 展开更多
关键词 Shanghai EXPO large space ATRIUM solar radiation ROof sprinkling system similarity theory prototype
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Theoretical design and experimental synthesis of counter electrode for dye-sensitized solar cells: Amino-functionalized graphene
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作者 Yiyi Jia Yantao Shi +1 位作者 Jieshan Qiu Ce Hao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2016年第5期861-867,共7页
For some specific catalytic reaction, how to construct active sites on two dimensional materials is of great scientific significance. Dye-sensitized solar cells(DSCs) can be viewed as one representative photovoltaic... For some specific catalytic reaction, how to construct active sites on two dimensional materials is of great scientific significance. Dye-sensitized solar cells(DSCs) can be viewed as one representative photovoltaics because in which liquid electrolyte with triiodide/iodide(I;/I;) as redox couples are involved. In this study, amino-functionalized graphene(AFG) has been designed according to theoretically analyzing iodine reduction reaction(IRR) processes and rationally screening the volcanic plot. Then, such AFG has been successfully synthesized by a simple hydrothermal method and shows high electrocatalytic activity towards IRR when serving as counter electrode in DSCs. Finally, a high conversion efficiency of 7.39% by AFG-based DSCs was obtained, which is close to that using Pt as counter electrode. 展开更多
关键词 Dye-sensitized solar cell Counter electrode Density functional theory Volcanic plot Amio-functionalized graphene
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A New Pathway for Incorporating the Impact of Solar Flares and Other Space Activity into Climate Modelling
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作者 Igor Suleimanov Sofya Prakhova Volker Rehbock 《Journal of Applied Mathematics and Physics》 2020年第10期2275-2285,共11页
A recent development in climate research is the recognition that space activity such as solar flares, gamma ray bursts, supernovas etc. can have a significant impact on the Earth. The existing methods of modelling spa... A recent development in climate research is the recognition that space activity such as solar flares, gamma ray bursts, supernovas etc. can have a significant impact on the Earth. The existing methods of modelling space activity do not model these phenomena explicitly. Instead, their effect on ionization rates is formulated and then built into existing climate models. In this paper, based on the authors’ earlier work, several analytical approaches for modelling a solar flare hitting the Earth are presented. These methods can also be used for modelling gamma-ray bursts or cosmic rays striking our planet. In addition, a method of calculating the total amount of radiation received during a solar flare is proposed. The future use of the proposed modelling approaches within comprehensive global climate models allows for explicit modelling of space activity and provides a new pathway for studying the possible effects of this activity on the Earth. 展开更多
关键词 Surface Integrals Vector Field theory solar Flares Climate Implications
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Recent theoretical progress in the development of perovskite photovoltaic materials 被引量:1
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作者 Xin Zhou Joanna Jankowska +1 位作者 Hao Dong Oleg V.Prezhdo 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2018年第3期637-649,共13页
Since the seminal work by Kojima et al. in 2009, solar cells based on hybrid organic-inorganic perovskites have attracted considerable attention and experienced an exponential growth, with photovoltaic efficiencies as... Since the seminal work by Kojima et al. in 2009, solar cells based on hybrid organic-inorganic perovskites have attracted considerable attention and experienced an exponential growth, with photovoltaic efficiencies as of today reaching above 22%. Despite such an impressive development, some key scientific issues of these materials, including the presence of toxic lead, the poor long-term device stability under heat and humidity conditions, and the anomalous hysteresis of the current-voltage curves shown by various solar cell devices, still remain unsolved and constitute an important focus of experimental and theoretical researchers throughout the world. Density functional theory calculations have been successfully applied to exploring structural and electronic properties of semiconductors, complementing the experimental results in search and discovery of novel functional materials. In this review, we summarize the current progress in perovskite photovoltaic materials from a theoretical perspective. We discuss design of lead-free perovskite materials, humidity-induced degradation mechanisms and possible origins for the observed solar cell hysteresis, and assess future research directions for advanced perovskite solar cells based on computational materials design and theoretical understanding of intrinsic properties. 展开更多
关键词 solar cells Perovskite materials Density functional theory
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Kubelka-Munk Revised Theory for High Solar Reflectance and High Long-wave Emissivity Coatings Designing 被引量:1
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作者 何燕 张雄 ZHANG Yongjuan 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2016年第1期100-107,共8页
The Kubelka-Munk revised theory was adopted to derive the mix design theory of high solar reflectance and high emissivity coatings.When the concentration of each colorant is within 20%,and the width of the coating is ... The Kubelka-Munk revised theory was adopted to derive the mix design theory of high solar reflectance and high emissivity coatings.When the concentration of each colorant is within 20%,and the width of the coating is more than 200 μm,each colorant has enough covering power in visible and near-infrared spectral range.It can be assumed that the addition of colorants in coatings can only change the solar spectral absorption ratio rather than solar spectral scattering coefficient.The spectral scattering coefficient of coatings tends to a constant.The spectral absorption-scattering property of each colorant can be characterized through one parameter.The spectral absorption-scattering coefficient of coatings can be calculated with the multivariate linear relationship of each pigment.Moreover,the results can be expanded for high solar reflectivity and high long-wave emissivity coating preparation.The accuracy of Kubelka-Munk revised theory has been tested and verified through comparison between the calculated value and tested value of coating reflectance. 展开更多
关键词 Kubelka-Munk revised theory high solar reflectivity high long-wave emissivity coatings covering power
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Rational molecular engineering towards efficient heterojunction solar cells based on organic molecular acceptors
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作者 张凯彦 宋朋 +1 位作者 马凤才 李源作 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期575-587,共13页
The selection of photoactive layer materials for organic solar cells(OSCs) is essential for the photoelectric conversion process.It is well known that chlorophyll is an abundant pigment in nature and is extremely valu... The selection of photoactive layer materials for organic solar cells(OSCs) is essential for the photoelectric conversion process.It is well known that chlorophyll is an abundant pigment in nature and is extremely valuable for photosynthesis.However,there is little research on how to improve the efficiency of chlorophyll-based OSCs by matching chlorophyll derivatives with excellent non-fullerene acceptors to form heterojunctions.Therefore in this study we utilize a chlorophyll derivative,Ce_(6)Me_(3),as a donor material and investigate the performance of its heterojunction with acceptor materials.Through density functional theory,the photoelectric performances of acceptors,i ncluding the fullerene derivative PC_(71)BM and the terminal halogenated non-fullerene DTBCIC series,are compared in detail.It is found that DTBCIC-C1 has better planarity,light absorption,electron affinity,charge reorganization energy and charge mobility than others.Ce_(6)Me_(3) has good energy level matching and absorption spectral complementarity with the investigated acceptor molecules and also shows good electron donor properties.Furthermore,the designed Ce_(6)Me_(3)/DTBCIC interfaces have improved charge separation and reorganization rates(K_(CS)/K_(CR)) compared with the Ce_(6)Me_(3)/PC_(71)BM interface.This research provides a theoretical basis for the design of photoactive layer materials for chlorophyll-based OSCs. 展开更多
关键词 organic solar cells density functional theory chlorophyll derivative non-fullerene acceptors
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Theoretical Studies on Structural and Spectroscopic Properties of Photoelectrochemical Cell Ruthenium Sensitizers―the Derivatives of N3
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作者 CHEN Jie WANG Jian +2 位作者 BAI Fu-quan ZHENG Qing-chuan ZHANG Hong-xing 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第4期696-702,共7页
A series of dye molecules was designed theoretically.Particularly,azoles and their derivatives were chosen as the modifying groups linking to ancillary ligands of [Ru(dcbpyH2)2(NCS)2](N3,dcbpy=4,4'-dicarboxy2,2... A series of dye molecules was designed theoretically.Particularly,azoles and their derivatives were chosen as the modifying groups linking to ancillary ligands of [Ru(dcbpyH2)2(NCS)2](N3,dcbpy=4,4'-dicarboxy2,2'-bipyridine;NCS=thiocyanato).Density functional theory(DFT) based approaches were applied to exploring the electronic structures and properties of all these systems.The dye molecule with 1,2,4-triazole groups which exhibits a very high intensity of absorption in visible region,was obtained.Time-dependent DFT(TD-DFT) results indicate that the ancillary ligand dominates the molecular orbital(MO) energy levels and masters the absorption transition nature to a certain extent.The deprotonation of anchoring ligand not only affects the frontier MO energy levels but also controls the energy gaps of the highest occupied MO(HOMO) to the lowest unoccupied MO(LUMO) and LUMO to LUMO+1 orbital.If the gap between LUMO-LUMO+1 is small enough,the higher efficiency of dye-sensitized solar cell(DSSC) should be expected. 展开更多
关键词 Dye-sensitized solar cell Density functional theory(DFT) Frontier molecular orbital Absorption spectrum DEPROTONATION
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Time of Conception and Birth-Relation of “Big Killers” Patients and Longevity
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作者 Eliyahu Stoupel Abdonas Tamoshiunas +7 位作者 Richardas Radishauskas Gailute Bernotiene Abid Assali Hanna Vaknin Igal Teplitzki Ran Kornowski Evgeny Abramson Eyal Fenig 《Health》 2014年第21期3062-3066,共5页
In recent years some interrelationships between time of birth and longevity were published. Concomitant publications appeared demonstrating links between Space Weather and the timing of medical events;in part of both ... In recent years some interrelationships between time of birth and longevity were published. Concomitant publications appeared demonstrating links between Space Weather and the timing of medical events;in part of both these studies it was shown that Space Weather indices are stronger connected with the time of conception as with the birth time. The aim of these study was to consider birth and conception month of patients suffering from a number of “big killer” pathologies, affecting human longevity and comparing with published data on centenarians—100 - 112 years old persons in the USA. Patients and Methods: We included monthly births distribution of our four papers including patients with Acute Myocardial Infarction undergoing Percutaneous Coronary Intervention (PCI)—n-3765, and admitted in another tertiary medical facility for AMI—n-22,047, and, also patients suffering Rapid—n-1239 and Sudden Cardiac Death—n-327 and, also, patients with oncologic malignancies—n-44587. At all in this group 71,965 patients were included. Their birth and conception months were compared with analogical data of 1574 people of 100 - 112 years old using data of L.A. and N.S. Gavrilov for USA centenarians. Results: The birth months of the cardiovascular and oncology patients were maximal in January, March and April (above 10% at each of these months);their conception was maximal in April, June and July. The monthly distribution of conception and birth of the studied population is presented in Tables 1-3. The maximal birth months of the centenarians were November, September, and October;the maximal conception months were December, January, and February. Conclusion: People suffering Myocardial Infarction, Sudden Cardiac Death and Oncologic Malignancies are in higher numbers born in the first four months of the year and conception in April, June and July. The maximal birth months of the very old people were November, September and October and conception were December, January and February. 展开更多
关键词 CONCEPTION birth Month Acute Myocardial Infarction Rapid SUDDEN Cardiac Death CENTENARIANS solar GEOMAGNETIC Cosmic Ray Activity
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Consideration of the Daily Variation of Gravity on the Manifestation of Gravitational Shielding
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作者 Toir Makhsudovich Radzhabov 《Journal of Geoscience and Environment Protection》 2022年第7期31-47,共17页
The result of mathematical and physical analysis of the daily change in gravity is presented. The subject of consideration was the manifestation of semi-daily factors in diurnal variations of gravity. The assumption i... The result of mathematical and physical analysis of the daily change in gravity is presented. The subject of consideration was the manifestation of semi-daily factors in diurnal variations of gravity. The assumption is investigated, according to which the cause of the half-day factors is the gravitational shielding of the planet Earth. Gravitational shielding is considered as a function of the size and thickness of celestial bodies and growing with distance from their poles. It is concluded that the planet Earth has the property of partial gravitational shielding, and the Moon does not have enough thickness to exhibit a tangible gravitational shielding. The obtained mathematical results correspond to the existing experimental data. It is suggested that gravitational shielding is the cause of the precession of the perihelion of Mercury and the peculiarities of the manifestation of tidal processes. It is assumed that gravitational shielding is one of the main reasons for the presence of hidden substances in the Universe. It is concluded that the physical picture with mutual shielding of interaction elements corresponds to the classical ideas of Fatio and Lesage. This approach is proposed as an alternative point of view to the existing theory on the description of tidal processes. It is shown that the existing basic approach to the description of tidal forces is unsatisfactory: the factors underlying the existing approaches have values 10 times less than those observed and cannot be considered as the reason for the manifestation of half-day manifestations in the daily change in gravity. The work is a continuation of the implementation by the author of P. Dirac’s ideas about accounting for the size of microparticles in physical theory. 展开更多
关键词 Gravitational Shielding Diurnal Variations of Gravity solar Eclipse Fatio-Lesage theory Gravity Anomalies Universal Gravitational Constant Semidiurnal Changes Precession of Mercury’s Perihelion Hidden Mass
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Study the Structural, Electronic, Optical Properties of CZTS Compound after Doping Ba at Zn Site and Si at Sn Site Using Density Functional Theory (DFT)
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作者 Fatema Najrin Rabeya Bakar Sarna +4 位作者 Sayedul Hasan Shariful Islam Budrun Neher Md. Mahbubur Rahman Bhuiyan Farid Ahmed 《Materials Sciences and Applications》 2024年第9期305-319,共15页
The structural, electronic, and optical properties of Cu2Zn1−xBaxSn1−ySiyS4 compounds have been calculated using GGA-PBE function within the framework of Density Functional Theory (DFT). In the present work, lattice p... The structural, electronic, and optical properties of Cu2Zn1−xBaxSn1−ySiyS4 compounds have been calculated using GGA-PBE function within the framework of Density Functional Theory (DFT). In the present work, lattice parameters remained the same, that is tetragonal crystal structure for 0% and 100% doping concentration. The electronic band gap of Cu2Zn1−xBaxSn1−ySiyS4 compounds has been gradually increased for continuous increment of doping concentration where the highest electronic band gap is 1.117 eV for Cu2BaSiS4 structure. Moreover, the band gap changes from direct to indirect band gap with the increase of doping concentration in the parent compound. The absorption coefficient has been found to be high (> 104 cm−1) in UV-region for all the doping concentration which makes the studied compound as a potential candidate of absorber layer in the UV detector. The theoretical study of the effect of double doping in the CZTS compound is very interesting for improving the quality of it and it would be a reference for the theoretical and experimental researchers. 展开更多
关键词 Photovoltaics Absorber Layer Density Functional theory (DFT) Band Gap solar Cell
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Theoretical investigation of photoelectric properties of the four-coordinate organoboron compounds based on diketopyrrolopyrrole derivativ
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作者 XING Lihua JIN Ruifa 《分子科学学报》 CAS 2024年第2期153-159,共7页
In order to obtain high efficiency of organic light-emitting diodes and organic solar cells,a series of DPP-based four-coordinate organoboron compounds have been designed for photoelectric functional materials.The eff... In order to obtain high efficiency of organic light-emitting diodes and organic solar cells,a series of DPP-based four-coordinate organoboron compounds have been designed for photoelectric functional materials.The effects of electron-donating and-withdrawing substituent on the electronic and optical properties have been investigated by using density functional theory(DFT)and time-dependent DFT(TD-DFT)approaches systematically.It turned out that electron-donating and-withdrawing groups can tune effectively the frontier molecular orbital(FMO)energy level,energy gap,and absorption and fluorescence spectra.The introduction of electron-withdrawing groups for the parent molecule HBDPP(2,5-bis(diphenylboryl)-3,6-bis(pyridin-2-yl)pyrrolo[3,4-c]pyrrole-1,4(2H,5H)-dione)favors the decrease for the FMO energy(E_(LUMO)and E_(HOMO)),HOMO-LUMO gaps(E_(g)),and the downhill energetic driving force(ΔEL-L),while the electron-donating groups can increase E_(LUMO),E_(HOMO),E_(g),andΔEL-L compared with that of HBDPP,respectively.The absorption and fluorescence spectra of the electron-withdrawing substituted derivatives exhibit bathochromic shifts,while the absorption and fluorescence spectra of the electrondonating substituted derivatives show hypsochromic shifts compared with the parent molecule HBDPP,respectively.Furthermore,the stronger the electron-withdrawing/donating ability of group is,the more significant the effect in the optoelectronic properties. 展开更多
关键词 DIKETOPYRROLOPYRROLE four-coordinate organoboron compound density functional theory optical property organic solar cell organic light-emitting diodes
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Relationship between Sea Surface Single Carrier Waves and Decreasing Pressures of Atmosphere Lower Boundary
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作者 Daika Augustin Mbane Biouele César 《Open Journal of Marine Science》 2015年第1期45-54,共10页
Descriptions of unusually high waves appearing on the sea surface for a short time (freak, rogue or killer waves) have been considered as a part of marine folklore for a long time. A number of instrumental registratio... Descriptions of unusually high waves appearing on the sea surface for a short time (freak, rogue or killer waves) have been considered as a part of marine folklore for a long time. A number of instrumental registrations have appeared recently making the community to pay more attention to this problem and to reconsider known observations of freak waves. To allow a better understanding of the behavior of rogue waves associated with tornadoes in terms of their origin, the nonlinear theory of off-balance systems is developed in the specific case of strong agitations constantly seen on the surface of extensive and deep rivers, when they are crossed by an atmosphere’s low pressure system (tornadoes, cyclones, hurricanes, etc.). A mathematical model based on the Navier-Stokes and Euler Lagrange equations coupled with assumptions derived from instrumental registrations on the training locations (or birth places) of freak waves is developed to enhance the physics of processes responsible for the formation (or origin) of the waves associated with atmosphere’s low pressure systems. Freak waves births’ constraints are mainly the need for both consistent water (i.e., extensive-deep rivers) and potential velocity flow availabilities. Numerical simulations, based on the use of the NLSE (Nonlinear Schrodinger Equation) are performed to validate our mathematical model on the births of single carrier waves associated with atmosphere’s low pressure systems. 展开更多
关键词 NONLINEAR theory of off-Balance systemS birthS of Single Carrier WAVES Associated with Atmosphere’s Low Pressure systemS NLSE (Nonlinear SCHRODINGER Equation)
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Ab-initio calculations of bandgap tuning of In1-xGaxY(Y=N,P)alloys for optoelectronic applications
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作者 Muhammad Rashid Jamil M +3 位作者 Mahmood Q Shahid M Ramay Asif Mahmood A Ghaithan H M 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第11期467-474,共8页
The III–V alloys and doping to tune the bandgap for solar cells and other optoelectronic devices has remained a hot topic of research for the last few decades.In the present article,the bandgap tuning and its influen... The III–V alloys and doping to tune the bandgap for solar cells and other optoelectronic devices has remained a hot topic of research for the last few decades.In the present article,the bandgap tuning and its influence on optical properties of In1-xGaxN/P,where(x=0.0,0.25,0.50,0.75,and 1.0)alloys are comprehensively analyzed by density functional theory based on full-potential linearized augmented plane wave method(FP-LAPW)and modified Becke and Johnson potentials(TB-mBJ).The direct bandgaps turn from 0.7 eV to 3.44 eV,and 1.41 eV to 2.32 eV for In1-xGaxN/P alloys,which increases their potentials for optoelectronic devices.The optical properties are discussed such as dielectric constants,refraction,absorption,optical conductivity,and reflection.The light is polarized in the low energy region with minimum reflection.The absorption and optical conduction are maxima in the visible region,and they are shifted into the ultraviolet region by Ga doping.Moreover,static dielectric constant e1(0)is in line with the bandgap from Penn’s model. 展开更多
关键词 density functional theory direct bandgap III-V semiconductors tuning of optical band gap solar cell applications
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The Sun’s Rotation Appears Differential plus Other New Views
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作者 Salah Abunaieb 《Natural Science》 CAS 2023年第4期167-178,共12页
This is a fresh perspective on the sun that considers its huge spherical size in relation to the finite speed of light. The sun is so extended that it takes light approximately 2.32 seconds to travel from the plane of... This is a fresh perspective on the sun that considers its huge spherical size in relation to the finite speed of light. The sun is so extended that it takes light approximately 2.32 seconds to travel from the plane of the solar limb to the plane tangential to the sun at the solar disc’s center. The aforementioned information is utilized in this study to support the new viewpoints. Firstly, it is shown that the solar disc is a simultaneous view of successively emitted coaxial spherical circles. Secondly, despite the fact that the sun is gaseous, it is thought to revolve completely as a rigid body at a fixed angular speed, yet an observer on Earth sees it rotate differentially. In a simple mathematical approach, it is found that the sun’s rotational speed apparently decreases with latitude. Thirdly, a qualitative examination of how we observe simultaneous whole-surface brightness changes of the sun and sunlike stars indicates that such changes would appear to spread out radially from the center of the solar disc. 展开更多
关键词 Sun Differential Rotation solar Radius solar Disc Speed of Light Special theory of Relativity Fading Stars
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Application of entransy theory in the heat transfer optimization of flat-plate solar collectors 被引量:5
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作者 LI QinYi CHEN Qun 《Chinese Science Bulletin》 SCIE CAS 2012年第2期299-306,共8页
The flat-plate solar collector is an important component in solar-thermal systems,and its heat transfer optimization is of great significance in terms of the efficiency of energy utilization.However,most existing flat... The flat-plate solar collector is an important component in solar-thermal systems,and its heat transfer optimization is of great significance in terms of the efficiency of energy utilization.However,most existing flat-plate collectors adopt metallic absorber plates with uniform thickness,which often works against energy conservation.In this paper,to achieve the optimal heat transfer performance,we optimized the thickness distribution of the absorber with the constraint of fixed total material volume employing entransy theory.We first established the correspondence between the collector efficiency and the loss of entransy,and then proposed the constrained extreme-value problem and deduced the optimization criterion,namely a uniform temperature gradient,employing a variational method.Finally,on the basis of the optimization criterion,we carried out numerical simulations,with the results showing remarkable optimization effects.When irradiation,the ambient temperature and the wind speed are 800 W/m2,300 K and 3 m/s,respectively,the collector efficiency is enhanced by 8.8% through optimization,which is equivalent to a copper saving of 30%.We also applied the thickness distribution optimized for wind speed of 3 m/s in heat transfer analysis with different wind speed conditions,and the collector efficiency was remarkably better than that for an absorber with uniform thickness. 展开更多
关键词 太阳能集热器 耗散理论 热优化 平板型 厚度分布 应用 能源利用效率 集热效率
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Performance analysis of a solar-aided power generation(SAPG) plant using specific consumption theory 被引量:2
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作者 HOU HongJuan WANG MengJiao +2 位作者 YANG YongPing CHEN Si HU Eric 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2016年第2期322-329,共8页
In contrast to a traditional coal-fired power generation plant where steam extracted from a turbine is used to preheat the feedwater in all preheating stages, a solar-aided power generation(SAPG) plant uses solar heat... In contrast to a traditional coal-fired power generation plant where steam extracted from a turbine is used to preheat the feedwater in all preheating stages, a solar-aided power generation(SAPG) plant uses solar heat to replace a part or all of the extracted steam in one or more preheating stages. The performance of an SAPG plant with different replacements is investigated in this study by using specific consumption theory(SCT). Fuel-specific and cost-specific consumption models for SAPG plants are built based on the SCT. A typical 330 MW coal-fired power plant is used as the study case. The performance of the SAPG plant in terms of specific consumption, with steam obtained from the first through the eighth(except for the fourth) stages of extraction replaced by solar heat, is compared with that of the reference coal-fired power plant. The fuel-specific consumption of the SAPG plant is determined to be lower than that of the reference coal-fired power plant. The fuel-specific consumption accrual distribution in SAPG plants is used to assess the effect of each individual replacement. Effective strategies to reduce the specific costs of the SAPG and coal-fired power plants are proposed based on the results of this study. 展开更多
关键词 燃煤发电厂 植物利用 消费模式 性能分析 太阳能 燃煤电厂 预热阶段 装置性能
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