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The Construction and Improvement of the Theoretical System of Ideological and Political Education in Colleges and Universities in the New Era
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作者 Rufei Zhao 《Journal of Contemporary Educational Research》 2025年第9期349-357,共9页
In the context of the new era,the construction and improvement of a theoretical system for ideological and political education in universities is a core proposition for fulfilling the fundamental task of cultivating m... In the context of the new era,the construction and improvement of a theoretical system for ideological and political education in universities is a core proposition for fulfilling the fundamental task of cultivating morality and educating people.Guided by Xi Jinping Thought on Socialism with Chinese Characteristics for a New Era and informed by the realities of social transformation,technological revolution,and educational reform in the new era,this article systematically analyzes the current status and prominent issues of the theoretical system for ideological and political education in universities.It analyzes the causes from the perspectives of concepts,mechanisms,and resources,and ultimately proposes a“three-dimensional collaborative”framework for system construction and specific strategies for improvement.This research aims to provide theoretical support and practical paths for theoretical innovation in ideological and political education in universities in the new era,helping to cultivate new generations of people who will shoulder the great responsibility of national rejuvenation. 展开更多
关键词 New era Ideological and political education in colleges and universities theoretical system Collaborative construction
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Theoretical System of Sandstone-Type Uranium Deposits in Northern China 被引量:11
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作者 Ruoshi Jin Huajian Liu Xiaoguang Li 《Journal of Earth Science》 SCIE CAS CSCD 2022年第2期257-277,共21页
Many theoretical results on sandstone-type uranium mineralization in northern China obtained by the uranium research team of the Tianjin Center of Geological Survey in recent years are presented.From the source sink s... Many theoretical results on sandstone-type uranium mineralization in northern China obtained by the uranium research team of the Tianjin Center of Geological Survey in recent years are presented.From the source sink system of uranium-producing basins,sedimentary environment of uranium-bearing rock series,ore-forming fluid information,evolution of tectonic events,basin formation and development,we redefine and classify uranium orebodies,redox zoning,and ore-controlling structural styles.We then systematically propose a theoretical system of sandstone-type uranium deposits in northern China.We conclude that sandstone-type uranium deposits in northern China are mainly found in sedimentary environments such as rivers,deltas,and alluvial fans in the Mesozoic and Cenozoic lowstand systems tract and in gray sandstone layers in the vertical redox zoning.The orebodies are controlled by the tectonic slope belt,which is in the shape of a strip on the plane,and spreads in a layer or plate on the section.Vertical(ups and downs)tectonic movement triggers large-scale phreatic flow in the basin,which is the real driving force for controlling the ore-forming fluid.The theoretical system of sandstone-type uranium deposits in northern China should be based on global tectonic movement and environmental changes and take into account factors such as basins as a unit to study mineralization background,ore concentration areas as objects to study mineralization,and the correlation between regional tectonic movement and metallogenic process as a breakthrough point to study tectonic events and metallogenic events.It should also be based on different basin types to establish metallogenic models.The innovative research results and ideas are summarized with the aim of promoting the continuous improvement of sandstone-type uranium mineralization theory in northern China. 展开更多
关键词 theoretical system metallogenic background MINERALIZATION metallogenic model vertical(ups and downs)tectonic movement sandstone-type uranium deposits ore deposit geology
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Forum on “Theoretical System of Human Rights” 被引量:1
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作者 ZHAO HAIQI 《The Journal of Human Rights》 2011年第2期26-27,共2页
The Human Rights magazine organized a workshop on December 23-24,2010 to discuss the "Theoretical System and Development Model of Human Rights" in socialism with Chinese characteristics.
关键词 theoretical system of Human Rights Forum on
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For a Socialist Theoretical System for Human Rights with Chinese Characteristics 被引量:1
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作者 GU CHUNDE 《The Journal of Human Rights》 2011年第2期6-7,共2页
I.The Necessity and Feasibility for Developing a Socialist Theoretical System for Human Rights with Chinese Characteristics Development of such a system is needed to ensure success of the social transformation and tra... I.The Necessity and Feasibility for Developing a Socialist Theoretical System for Human Rights with Chinese Characteristics Development of such a system is needed to ensure success of the social transformation and transition ongoing up in China 展开更多
关键词 For a Socialist theoretical system for Human Rights with Chinese Characteristics
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Earth Ecosystem Theory: I Theoretical System
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作者 Yang Dongfang Wang Fengyou +2 位作者 Zhu Sixi He Huazhong Wu Yunjie 《Meteorological and Environmental Research》 CAS 2014年第9期11-12,17,共3页
Earth is the place of human existence and life. Without the earth,there is no human,no nature either. To study human existence,the earth of human living is firstly studied. By the study of many natural phenomena on th... Earth is the place of human existence and life. Without the earth,there is no human,no nature either. To study human existence,the earth of human living is firstly studied. By the study of many natural phenomena on the earth,we firstly put forward the theory of earth ecosystem,expound its definition,structure,aim,function,content and significance,and illustrate the characteristics of earth ecosystem. So we found the theory of earth ecosystem,and unveil the variable processes and the operation mechanisms of earth ecosystem. We put forward the earth ecosystem and its theoretic system,which are different from the previous " earth system science" and " Gaia hypothesis". We consider that among each part of the environment,between environment and organism,there are organic,close and coalescent relationships,so that the earth ecosystem is able to have a sustainable development. Even if there is no life,the earth ecosystem also can control and regulate the earth changes,and possesses the stable state. Therefore,the foundation of the earth ecosystem theory is conducive to the studies of the global problems: the change processes and trends of resources,ecologies,environments,disasters,and so on. 展开更多
关键词 Earth ecosystem theoretical system Definition Content Characteristics China
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Observations on the Theoretical System of People-to-People Diplomacy with Chinese Characteristics in the New Era
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作者 Zhang Shengjun Ai Hong 《International Understanding》 2013年第1期17-21,共5页
With salient hallmarks of the time,people-topeople diplomacy with Chinese characteristics was proposed against the backdrop of China’s integration with the world as well as the strategic transformation of China’s pe... With salient hallmarks of the time,people-topeople diplomacy with Chinese characteristics was proposed against the backdrop of China’s integration with the world as well as the strategic transformation of China’s people-to-people diplomacy.The establishment of a theoretical system for it conforms to the new situation and new requirements of the times,and is line 展开更多
关键词 Observations on the theoretical system of People-to-People Diplomacy with Chinese Characteristics in the New Era
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The theoretical basis and development of new quality productive forces in China's ice and snow economy
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作者 LI Yu GONG Rongrong +2 位作者 DONG Suocheng XIA Bing SHI Donghui 《Journal of Geographical Sciences》 2025年第10期2161-2185,共25页
This study proposes a framework for the concept of“new quality productive forces”in the ice and snow economy(ISE)as a strategic response to global climate change and the demands of technological and industrial trans... This study proposes a framework for the concept of“new quality productive forces”in the ice and snow economy(ISE)as a strategic response to global climate change and the demands of technological and industrial transformation for high-quality development.These new quality productive forces in the ISE have developed alongside the zonal distribution of natural resources,strictly adhere to ecological principles,and integrate value transformation mechanisms specific to ice and snow resources.Their development is projected to generate multiple benefits across ecological,economic,and social dimensions.The new quality productive forces in the ISE are characterized by technology-driven resource development,synergistic integration across the entire ice and snow industry value chain,and a focus on high-quality,green growth.Grounded in geography and economics,the new quality productive forces in the ISE link scientific innovation,the reallocation of productive factors,and industrial upgrading within the context of resource constraints.Furthermore,they expand the growth potential of the ISE by fostering new production relations through digital,intelligent,and green integration,while advancing low-carbon,sustainable development under the guiding principle that“ice and snow landscapes are also mountains of gold and silver.”For China's ISE,these new quality productive forces emphasize rigorous resource protection,balanced human-environment relationships,a resilient integrated supply chain framework,and an efficient“dual circulation”economic model.Practical strategies include integrating production factors,optimizing spatial resource allocation,fostering industrial synergy,and adapting production relations,all aimed at advancing the sustainable and high-quality development of China's ISE. 展开更多
关键词 ice and snow economy new quality productive forces connotations and characteristics theoretical system development directions
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Systematic and Theoretical Unfolding of Research on Xi Jinping’s Discourses on Respecting and Protecting Human Rights
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作者 张新平 周艺晨 LI Rong(Translated) 《The Journal of Human Rights》 2024年第2期255-286,共32页
Xi Jinping’s discourses on respecting and protect-ing human rights stand as a shining example of the sinicization and modernization of Marxist human rights theory,embodying profound theoretical,political,practical,an... Xi Jinping’s discourses on respecting and protect-ing human rights stand as a shining example of the sinicization and modernization of Marxist human rights theory,embodying profound theoretical,political,practical,and cultural logic.Existing research has conducted comprehensive and systematic theoretical analysis and academic extractions on the following contents:the core essence in-herent in these important discourses,including the“theory of human rights concepts,”the“theory of human rights paths,”the“theory of human rights practices,”the“theory of human rights protection,”and the“theory of human rights governance,”along with their profound theoretical significance,practical significance,and global signifi-cance.In the future,researchers should emphasize efforts on studying the original texts and understanding the original principles.While focusing on the precision of concepts,the scientific nature of the prop-ositions,the maturity of theoretical systems,and the rigor of internal logic related to Xi Jinping’s discourses on respecting and protecting human rights,researchers should also pay attention to constructing a discourse system on human rights from the dimensions of discourse power,discourse cluster,and discourse field.Researchers should be adept at drawing innovative insights into human rights theory from China’s vibrant human rights practices and the vast masses of people.This approach will facilitate the systematic unfolding,academic trans-formation,and innovative development of Xi Jinping’s discourses on respecting and protecting human rights. 展开更多
关键词 respecting and protecting human rights systematic nature of content theoretical transformation of achievements
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Enhance Human Rights Studies and Construct China’s Autonomous Knowledge System of Human Rights 被引量:1
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作者 Baimachilin LIU Haile(Translated) 《The Journal of Human Rights》 2025年第1期3-9,共7页
Xi Jinping,general secretary of the Communist Party of China(CPC)Central Committee,stressed that we should adhere to the“two integrations”(namely,integrating the basic tenets of Marxism with China’s specific realit... Xi Jinping,general secretary of the Communist Party of China(CPC)Central Committee,stressed that we should adhere to the“two integrations”(namely,integrating the basic tenets of Marxism with China’s specific realities and fine traditional culture),root ourselves in Chinese soil,carry forward the Chinese cultural heritage,and strengthen the academic foundation.We should accelerate the building of an independent knowledge system for Chinese philosophy and social sciences,and formulate original concepts and develop systems of academic discipline,research and discourse,drawing on China’s rich experience of advancing human rights.In the face of changes of a magnitude not seen in a century,in the historic process of advancing the great rejuvenation of the Chinese nation on all fronts through Chinese modernization,we should and must strengthen our theoretical self-consciousness and confidence in the path of Chinese modernization.We need to enhance human rights research,develop the human rights theoretical system and paradigm that are based on Chinese realities and express Chinese voice,and an independent Chinese knowledge system for human rights. 展开更多
关键词 theoretical self consciousness formulate original concepts deve cultural heritage MARXISM autonomous knowledge system human rights Chinese realities basic tenets marxism
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Corrigendum to“Mechanistic Insights into Water-Mediated CO_(2)Electrochemical Reduction Reactions on Cu@C_(2)N Catalysts:A Theoretical Study”[Acta Physico-Chimica Sinica(2024)40,2303040]
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《物理化学学报》 北大核心 2025年第5期144-144,共1页
Hanyu Xu 1,Xuedan Song 1,*,Qing Zhang 1,Chang Yu 1,Jieshan Qiu 1,2,*1 Liaoning Key Lab for Energy Materials and Chemical Engineering,State Key Laboratory of Fine Chemicals,School of Chemical Engineering,Dalian Univers... Hanyu Xu 1,Xuedan Song 1,*,Qing Zhang 1,Chang Yu 1,Jieshan Qiu 1,2,*1 Liaoning Key Lab for Energy Materials and Chemical Engineering,State Key Laboratory of Fine Chemicals,School of Chemical Engineering,Dalian University of Technology,Dalian 116024,Liaoning Province,China. 展开更多
关键词 chemical engineeringdalian theoretical study water mediated Cu C N catalysts fine chemicalsschool CO electrochemical reduction chemical engineeringstate
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Solid-state Effects on Luminescence Properties of TADF Emitters Based on Pyrido[2,3-b]pyrazine-Dihydrophenazasilines Donor-acceptor Structures:Theoretical Study
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作者 LI Yuheng LIU Meiqi +2 位作者 HOU Baoming PAN Yuyu YANG Bing 《发光学报》 北大核心 2025年第2期354-365,共12页
Thermally activated delayed fluorescence(TADF)molecules have outstanding potential for applications in organic light-emitting diodes(OLEDs).Due to the lack of systematic studies on the correlation between molecular st... Thermally activated delayed fluorescence(TADF)molecules have outstanding potential for applications in organic light-emitting diodes(OLEDs).Due to the lack of systematic studies on the correlation between molecular structure and luminescence properties,TADF molecules are far from meeting the needs of practical applications in terms of variety and number.In this paper,three twisted TADF molecules are studied and their photophysical properties are theoretically predicted based on the thermal vibrational correlation function method combined with multiscale calculations.The results show that all the molecules exhibit fast reverse intersystem crossing(RISC)rates(kRISC),predicting their TADF luminescence properties.In addition,the binding of DHPAzSi as the donor unit with different acceptors can change the dihedral angle between the ground and excited states,and the planarity of the acceptors is positively correlated with the reorganization energy,a property that has a strong influence on the non-radiative process.Furthermore,a decrease in the energy of the molecular charge transfer state and an increase in the kRISC were observed in the films.This study not only provides a reliable explanation for the observed experimental results,but also offers valuable insights that can guide the design of future TADF molecules. 展开更多
关键词 solid-state effects thermally activated delayed fluorescence(TADF) theoretical study multi-scale simulation
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A Numerical and Theoretical Study on the Perforation of Aluminum Plates Struck by Flat-Nosed Projectiles
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作者 L.F.Yang H.M.Wen 《Acta Mechanica Solida Sinica》 2025年第4期570-587,共18页
It has been experimentally observed that,in the perforation of metal plates by a flat-nosed projectile,there exists a plateau phenomenon where the ballistic limit increases slightly with increasing plate thickness,whi... It has been experimentally observed that,in the perforation of metal plates by a flat-nosed projectile,there exists a plateau phenomenon where the ballistic limit increases slightly with increasing plate thickness,which is related to a change in the mode of failure.No theoretical model has so far explained this phenomenon satisfactorily.This paper presents a combined numerical and theoretical study on the perforation of 2024-T351 aluminum plates struck by flat-nosed projectiles.First,numerical simulations are performed to investigate the failure mechanisms/deformation modes of the aluminum plates.Then,a theoretical model is proposed based on the numerical results and the experimental observations within a unified framework.The model takes into account the main energy absorbing mechanisms and the corresponding energies absorbed are determined analytically.In particular,a dimensionless equation is suggested to describe the relationship between global deformations and impact velocity.It transpires that the model predictions are in good agreement with the test data and the numerical results for the perforation of 2024-T351 aluminum plates struck by rigid flat-nosed projectiles in terms of residual velocity,ballistic limit,relationship between global deformations and impact velocity,and transition of failure modes.It also transpires that the present model can predict the“plateau”phenomenon,which shows a slight increase in ballistic limit as plate thickness increases.Furthermore,the energy absorption mechanisms are discussed on the basis of the theoretical analysis. 展开更多
关键词 Aluminum plate Flat-nosed projectile PERFORATION Energy absorption Numerical simulation theoretical model
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Analysis of Obstructive Factors for Medical Staff to Implement Respiratory Rehabilitation Evidence Based on the Theoretical Domain Framework
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作者 Ying Gao Junying Nie +2 位作者 Xiaoling Bai Yajuan Shi Ying Li 《Journal of Clinical and Nursing Research》 2025年第10期62-71,共10页
Objective:To explore the obstructive factors in the behavior of medical staff during the implementation of respiratory rehabilitation process,and to provide a basis for the rehabilitation management intervention of CO... Objective:To explore the obstructive factors in the behavior of medical staff during the implementation of respiratory rehabilitation process,and to provide a basis for the rehabilitation management intervention of COPD.Methods:A descriptive nature research method was adopted.An interview outline was formulated based on the theoretical domain framework.From October to December 2024,15 medical staff from the respiratory department of a tertiary hospital in Shaanxi Province were selected for semi-structured interviews.The interview data were analyzed using the Colaizzi 7-step analysis method.Result:The analysis of this study found that the obstructive factors for medical staff to implement respiratory rehabilitation include five theoretical domains.The problems are respectively the lack of knowledge about respiratory rehabilitation and insufficient training intensity,the insufficient self-recognition of implementing respiratory rehabilitation,the low awareness rate of patients and the low cooperation degree,the insufficient provision of instruments and facilities,the lack of rehabilitation training venues and respiratory rehabilitation clinics,and the lack of scientific and standardized respiratory rehabilitation management processes.Conclusion:There are many obstructive factors affecting the implementation of respiratory rehabilitation by medical staff.Clinical managers should take corresponding measures,continuously improve the rehabilitation management strategies for COPD,and promote the clinical application of the best evidence for respiratory rehabilitation. 展开更多
关键词 Apply evidence COPD Obstructive factors Qualitative research Respiratory rehabilitation theoretical domain framework
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Theoretical and Experimental Investigations on Thickness Uniformity in Double-sided Lapping
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作者 Zhuolin Cai Zhe Yang +4 位作者 Bo Pan Jiale Lian Lianlin Wang Sergei Pronkevich Jiang Guo 《Chinese Journal of Mechanical Engineering》 2025年第3期151-163,共13页
The double-sided lapping process is extensively employed in the manufacturing of wafers,optical windows,and seal rings due to its high efficiency and ability to achieve precise flatness.However,limited research has ex... The double-sided lapping process is extensively employed in the manufacturing of wafers,optical windows,and seal rings due to its high efficiency and ability to achieve precise flatness.However,limited research has explored the thickness uniformity among different workpieces after double-sided lapping,and the underlying mechanism remains unclear.To address the demand for higher precision,this paper first analyzed the relative kinematic model between the workpiece and the lapping plate to clarify the causes of thickness variations among workpieces after double-sided lapping.Subsequently,a finite element method(FEM)model was developed to account for the pressure distribution on the workpiece surfaces at the initial stage of the process.The results indicate that the number of workpieces influences the final thickness variation.Then,various sets of thin copper plates with different thicknesses were lapped,and the findings revealed that five copper plates processed simultaneously exhibited more uniform thickness compared to the three plates.The experimental results align well with the theoretical analysis.Ultimately,a thickness variation of less than 6μm was achieved on five copper plates measuringΦ100×2.9 mm.This study presents a comprehensive analysis of the mechanisms influencing thickness uniformity in the double-sided lapping process and provides practical guidelines for optimizing the process to achieve stringent precision standards in industrial applications. 展开更多
关键词 Double-sided lapping Thickness uniformity theoretical analysis FEM Thin copper plate
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Historical Basis,Theoretical Implication,and Practical Significance:A Three-Dimensional Analysis of Marx’s Thoughts on Clean Government
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作者 Faying Ding Cong Liu +1 位作者 Qun Wang Gongxu Tan 《Journal of Contemporary Educational Research》 2025年第7期346-355,共10页
Marx scientifically summarized the experience and lessons of the Paris Commune,deeply exposed the root causes of bourgeois corruption,and emphasized the purity and advancement of the construction of proletarian politi... Marx scientifically summarized the experience and lessons of the Paris Commune,deeply exposed the root causes of bourgeois corruption,and emphasized the purity and advancement of the construction of proletarian political parties and political power.The dictatorship of the proletariat puts forward the ideas of cheap government that eradicate corruption,realizes that the people are the masters of the country,implements democratic supervision of elections,simplifies the construction of institutions,lowers governance costs,and achieves higher efficiency.A deep understanding of the theoretical characteristics of Marx’s thoughts on integrity,democracy,and honor,and a profound clarification of the practical significance of Marx’s ideology on clean governance,combined with practical practice,will help promote the construction of a new system of anti-corruption and incorruption in our country,and will benefit our contemporary services.The construction of a type-oriented government system is conducive to deepening the construction of China’s national legal system. 展开更多
关键词 Marx Thoughts on clean government Historical basis theoretical implications SIGNIFICANCE
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Theoretical Study on Photoinduced Triplet Electron Transfer at the Interface of Pd-Octaethylporphyrin and Tungsten Disulfide
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作者 Yang Zhang Wen-Qi Zhao +3 位作者 Wen-Kai Chen Xiao-Ying Xie Wei-Hai Fang Ganglong Cui 《Chinese Journal of Chemical Physics》 2025年第1期113-124,I0050-I0054,I0057,共18页
Heterostructures of organic semi-conductors and transition metal dichalcogenides(TMDs)are viable candidates for superior optoelec-tronic devices.Photoinduced inter-facial charge transfer is crucial for the performance... Heterostructures of organic semi-conductors and transition metal dichalcogenides(TMDs)are viable candidates for superior optoelec-tronic devices.Photoinduced inter-facial charge transfer is crucial for the performance efficiency of such devices,yet the underlying mecha-nism,especially the roles of optical-ly dark triplets and spatially sepa-rated charge transfer states,is poorly understood.In the present work,we obtain the struc-tures of distinct excited states and investigate how they are involved in the charge transfer process at the Pd-octaethylporphyrin(PdOEP)and WS_(2) interface in terms of their energies and couplings.The results show that electron transfer from the triplet PdOEP formed via intersystem crossing prevails over direct electron transfer from the singlet(two orders of magnitude faster).Further analysis reveals that the relatively higher rate of triplet electron transfer compared to singlet electron transfer is mainly attributed to a smaller reorganization energy,which is dominated by the out-of-plane vibrations of the organic component.The work emphasizes the important roles of the optically dark triplets in the electron transfer of the PdOEP@WS_(2) heterostructure,and provides valuable theoretical insights for further improv-ing the optoelectronic performance of TMD-based devices. 展开更多
关键词 Interfacial charge transfer Photoinduced carrier dynamics theoretical study Pd-octaethylporphyrin Triplet electron transfer Tungsten disulfide
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One-dimensional theoretical analysis on charged-particle transports in a decaying plasma with an initial plasma-electrode gap
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作者 Xin-Li Sun Yao-Ting Wang +5 位作者 Lan-Yue Luo Zi-Ming Zhang Meng-Long Zhang He-Ping Li Dong-Jun Jiang Ming-Sheng Zhou 《Chinese Physics B》 2025年第11期447-459,共13页
An analytical model for describing the charged-particle transport in a wall-confined laser-induced decaying plasma is established under an external electrostatic field,focusing on the effects of the initial plasma-ele... An analytical model for describing the charged-particle transport in a wall-confined laser-induced decaying plasma is established under an external electrostatic field,focusing on the effects of the initial plasma-electrode gap(IPEG)that exists in applications such as laser isotope separation.This newly developed analytical model is validated by particle-in-cell simulations and the experimental scaling relation,and can also be reduced to its previously published counterpart that did not consider IPEGs.Based on this analytical model,the influences of different IPEG spacings on the characteristics of the whole ion extraction process are studied.The results show that the ion extraction ratios at the endpoints of the first and second stages both decrease with increasing IPEG spacing,while the corresponding time durations for the first two stages show a non-monotonous variation trend.The specific ion extraction time,defined as the ion extraction time per unit mass to comprehensively characterize the ion extraction efficiency,increases generally with the increase of IPEG spacing.This study not only provides further insight into the fundamental physical processes in a wall-bounded decaying plasma under an externally applied electrostatic field,but also offers useful theoretical guidance for optimal designs of geometrical and operating parameters in laser isotope separation processes. 展开更多
关键词 decaying plasma charged-particle transport effect of plasma-electrode gap theoretical analysis PIC simulation
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Theoretical perspective on fine-tuning ISC efficiency in D-A BODIPY photosensitizers through heteroatom incorporation and nitrogen ring strain modulation
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作者 Jianfang Cao Xue Ma +2 位作者 Xinyu Chen Tianci Zhang Wen Sun 《Chinese Chemical Letters》 2025年第10期241-245,共5页
This study investigates the intersystem crossing(ISC)mechanism in donor-acceptor(D-A)type distyryl-BODIPY photosensitizers,including previously reported M1(benzene donor),M2,M3(phenothiazine donors),and newly predicte... This study investigates the intersystem crossing(ISC)mechanism in donor-acceptor(D-A)type distyryl-BODIPY photosensitizers,including previously reported M1(benzene donor),M2,M3(phenothiazine donors),and newly predicted M4(triphenylamine donor),M5-M7(nitrogen-containing aliphatic rings with thiophene donors).Using computational chemistry,we analyzed their geometric configurations,spectral properties,spin-orbit coupling,and electron-hole orbitals.We found that S_(2) is a charge transfer singlet state(^(1)CT),T2is a locally excited triplet state(^(3)LE),and the S_(2)→T_(2)transition is the main ISC pathway in M2-M7,following the ^(1)CT→^(3)LE mechanism.M5-M7 show near-vertical dihedral angles between donor and acceptor in the S_(2) state relative to M2-M4,facilitating charge transfer.The strain energies in the nitrogen-containing rings of M5-M7 affect oxidation potentials and ISC.M5,with the highest strain energy,shows the lowest oxidation potential,smaller△_(ES2-T2),highest SOC,and fastest kisc,making it the most efficient predicted singlet oxygen producer.This research clarifies the structure-performance relationships of near-infrared D-A type distyryl-BODIPY photosensitizers and provides a theoretical foundation for developing heavy-atom-free photosensitizers with tuned fluorescence quantum yield and singlet oxygen quantum yield. 展开更多
关键词 Donor-acceptor(D-A)type PHOTOSENSITIZERS Charge transfer and charge recombination Distyryl-BODIPY photosensitizers Photodynamic therapy theoretical calculation
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An experimental and theoretical study on the influence of stress gradients on the propagation of hydraulic fractures
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作者 Junchi Liu Yuping Sun +8 位作者 Pingping Liang Yintong Guo Yuting He Wenjie Xu Duanyang Zhuang Jinlong Li Liangtong Zhan Jianfu Shao Yunmin Chen 《International Journal of Mining Science and Technology》 2025年第9期1543-1553,共11页
Hydraulic fracture growth is significantly influenced by the minimum horizontal principal stress gradient and the fracturing fluid pressure gradient.However,these gradients are often neglected in scaled physical model... Hydraulic fracture growth is significantly influenced by the minimum horizontal principal stress gradient and the fracturing fluid pressure gradient.However,these gradients are often neglected in scaled physical modeling experiments due to difficulties in reproducing them.This study uses centrifugal hypergravity to simulate both gradients and investigate their effects on fracture propagation.Artificial mortar specimens(ϕ200 mm×400 mm)are fractured under 1g(normal gravity),50g,and 100g.Results show that compared to 1g,fractures under 50g and 100g exhibit increasingly uneven propagation,with higher g-values leading to greater asymmetry.To interpret this,a theoretical analysis based on fracture mechanics is conducted.When the fluid pressure gradient exceeds the stress gradient,a positive net gradient is generated,increasing net pressure at the lower fracture tip.This raises the stress intensity factor at the lower tip,promoting downward growth.As g increases,the disparity becomes more significant,resulting in greater fracture deviation.In conclusion,this study,for the first time,has verified and explained that the net gradient can change the propagation of hydraulic fractures,providing important guidance for wellbore placement under stress gradients. 展开更多
关键词 Stress gradients Hydraulic fracture propagation Centrifugal experiments theoretical analysis
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Tricycloquinazoline-based monolayer conjugated metal-organic frameworks as promising hydrogen storage media:A theoretical investigation
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作者 Zhaoshun Meng Qingyu Li +2 位作者 Huilin Sun Yunhui Wang Xing'ao Li 《Green Energy & Environment》 2025年第6期1326-1336,共11页
The pursuit of sustainable energy has driven a significant interest in hydrogen(H_(2))as a clean fuel alternative.A critical challenge is the efficient storage of H_(2),which this study addresses by examining the pote... The pursuit of sustainable energy has driven a significant interest in hydrogen(H_(2))as a clean fuel alternative.A critical challenge is the efficient storage of H_(2),which this study addresses by examining the potential of tricycloquinazoline-based monolayer metal-organic frameworks(MMOFs with the first“M”representing metal species).Using density functional theory,we optimized the structures of MMOFs and calculated H_(2)adsorption energies above the open metal sites,identifying ScMOF,TiMOF,NiMOF,and MgMOF for further validation of their thermodynamic stability via ab-initio molecular dynamics(AIMD)simulations.Force field parameters were fitted via the Morse potential,providing a solid foundation for subsequent grand canonical Monte Carlo simulations.These simulations revealed that the maximum of saturated excess gravimetric H_(2)uptake exceeds 14.16 wt%at 77 K,surpassing other reported MOFs,whether they possess open metal sites or not.At 298 K and 100 bar,both the planar and distorted structures derived from our AIMD simulations demonstrated comparable excess gravimetric H_(2)uptake within the range of 3.05 wt%to 3.94 wt%,once again outperforming other MOFs.Furthermore,lithium(Li)doping significantly enhanced the excess H_(2)uptake,with Li-TiMOF achieving an impressive 6.83 wt%at 298 K and 100 bar,exceeding the ultimate target set by the U.S.Department of Energy.The exceptional H_(2)adsorption capacities of these monolayer MOFs highlight their potential in H_(2)storage,contributing to the design of more efficient hydrogen storage materials and propelling the sustainable hydrogen economy forward. 展开更多
关键词 Hydrogen storage 2D monolayer MOFs Open metal sites Lithium doping theoretical investigation
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