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Research on strategies for the high-quality development of science popularization work by Chinese scientific and technological societies
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作者 Minchao Wang Renkai Zhang 《Cultures of Science》 2025年第1期38-51,共14页
With long-term government support and col ective societal engagement,China's scientific and technological(S&T)societies have achieved significant progress in science popularization(SP),substantially contributi... With long-term government support and col ective societal engagement,China's scientific and technological(S&T)societies have achieved significant progress in science popularization(SP),substantially contributing to the enhancement of national science communication capabilities and the improvement of citizens'scientific literacy.Within the overarching framework of advancing the high-quality development of China's SP endeavours in the new era,the high-quality development of SP by S&T societies plays a pivotal role.This study systematical y examines the chal enges and dilemmas confronting the high-quality development of SP within China's S&T societies.Theoretical y,it expands the research framework of col aborative mechanisms in science communication,while practical y proposing the construction of a‘six-in-one’high-quality SP service system encompassing brand development,platform construction,talent cultivation,specialized projects,incentive mechanisms and infrastructure development.Our research further reveals that empowering SP content innovation through digital and intel igent technologies,as wel as optimizing the compatibility of policy instrument portfolios,can strengthen the efficacy of SP services and provide systematic support for the modernization of S&T societies.This study not only offers policy references for improving the governance system of SP but also identifies future research directions,such as deepening comparative international studies and long-term efficacy evaluations,to advance the development of more explanatory theoretical frameworks.These efforts aim to bolster high-level S&T self-reliance and contribute to the construction of a world-leading scientific,educational and talent powerhouse. 展开更多
关键词 Scientific and technological societies science popularization high-quality development
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The conceptual development of the science-fiction industry and its main forms and features
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作者 Yilin Xu Wenjie Zhao Ling Chen 《Cultures of Science》 2024年第2期147-158,共12页
The term ‘science fiction(sci-fi) industry' has developed only in the past two decades in China. It has gone through special cultural, economic and political backgrounds in its conceptual development. After years... The term ‘science fiction(sci-fi) industry' has developed only in the past two decades in China. It has gone through special cultural, economic and political backgrounds in its conceptual development. After years of evolution and under the influence of some influential sci-fi intellectual properties, the sci-fi industry has developed typical forms such as reading material, film and television programs, games, derivative products and cultural tourism. These forms are also the major means for the generation of sci-fi content and the dissemination of sci-fi culture. The sci-fi industry has three key features: it integrates culture with science and technology as production factors;it has both production capacity and consumer appeal;and it is made up of interconnected vertical and horizontal production chains. 展开更多
关键词 Science fiction sci-fi industry sci-fi forms sci-fi features China
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B-site ion regulation strategy enables performance optimization and multifunctional integration of hybrid perovskite ferroelectrics
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作者 Hao-Fei Ni Jia-He Lin +7 位作者 Gele Teri Qiang-Qiang Jia Pei-Zhi Huang Hai-Feng Lu Chang-Feng Wang Zhi-Xu Zhang Da-Wei Fu Yi Zhang 《Chinese Chemical Letters》 2025年第3期555-559,共5页
The performance optimization of materials is an eternal theme and challenge in scientific research,which is reflected in ferroelectric filed to two hot topics of enhancing Curie temperature(TC)and functional versatili... The performance optimization of materials is an eternal theme and challenge in scientific research,which is reflected in ferroelectric filed to two hot topics of enhancing Curie temperature(TC)and functional versatility.The former one vitally determines ferroelectric operational temperature range while the latter would open up new application possibilities.Effective chemical modification or doping strategies on A-site and X-site components have been successfully developed in hybrid organic-inorganic perovskite(HOIP)ferroelectrics,however,the important role of adjusting B-site ions has long been overlooked.Here,we have implemented regulation on the ion radius of the B-site component to successfully obtain two new HOIP ferroelectrics(3-pyrrolinium)BBr_(3)(B=Mn and Ni).Compared to parent(3-pyrrolinium)CdBr_(3),the TC(△T=99 K)was significantly optimized by replacing the Cd^(2+)with smaller Mn^(2+)or Ni^(2+)ions.More strikingly,the introduction of Mn^(2+)and Ni^(2+)ions with octahedral coordination bring out intriguing red emission and magnetism respectively,making the multifunctional integration in a single material for multiple uses.This work provides a feasible strategy for performance optimizing of HOIP ferroelectrics,and would shed light for constructing multifunctional ferroelectrics. 展开更多
关键词 FERROELECTRIC Hybrid perovskites Crystal engineering Curie temperature Phase transition
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Discovering causal models for structural,construction and defense-related engineering phenomena
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作者 M.Z.Naser 《Defence Technology(防务技术)》 2025年第1期60-79,共20页
Causality,the science of cause and effect,has made it possible to create a new family of models.Such models are often referred to as causal models.Unlike those of mathematical,numerical,empirical,or machine learning(M... Causality,the science of cause and effect,has made it possible to create a new family of models.Such models are often referred to as causal models.Unlike those of mathematical,numerical,empirical,or machine learning(ML)nature,causal models hope to tie the cause(s)to the effect(s)pertaining to a phenomenon(i.e.,data generating process)through causal principles.This paper presents one of the first works at creating causal models in the area of structural and construction engineering.To this end,this paper starts with a brief review of the principles of causality and then adopts four causal discovery algorithms,namely,PC(Peter-Clark),FCI(fast causal inference),GES(greedy equivalence search),and GRa SP(greedy relaxation of the sparsest permutation),have been used to examine four phenomena,including predicting the load-bearing capacity of axially loaded members,fire resistance of structural members,shear strength of beams,and resistance of walls against impulsive(blast)loading.Findings from this study reveal the possibility and merit of discovering complete and partial causal models.Finally,this study also proposes two simple metrics that can help assess the performance of causal discovery algorithms. 展开更多
关键词 CAUSALITY Causal discovery Directed acyclic graphs Machine learning Metrics
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Advancements in remote sensing techniques for earthquake engineering:A review
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作者 Chinmayi H.K K.Colton Flynn Amanda J.Ashworth 《Earthquake Research Advances》 2025年第3期110-122,共13页
Remote sensing technologies play a vital role in our understanding of earthquakes and their impact on the Earth's surface.These technologies,including satellite imagery,aerial surveys,and advanced sensors,contribu... Remote sensing technologies play a vital role in our understanding of earthquakes and their impact on the Earth's surface.These technologies,including satellite imagery,aerial surveys,and advanced sensors,contribute significantly to our understanding of the complex nature of earthquakes.This review highlights the advancements in the integration of remote sensing technologies into earthquake studies.The combined use of satellite imagery and aerial photography in conjunction with geographic information systems(GIS)has been instrumental in showcasing the significance of fusing various types of satеllitеdata sourcеs for comprеhеnsivееarthquakеdamagеassеssmеnts.However,remote sensing encounters challenges due to limited pre-event imagery and restricted postearthquake site access.Furthеrmorе,thеapplication of dееp-lеarning mеthods in assеssingеarthquakе-damagеd buildings dеmonstratеs potеntial for furthеr progrеss in this fiеld.Overall,the utilization of remote sensing technologies has greatly enhanced our comprehension of earthquakes and their effects on the Earth's surface.The fusion of remote sensing technology with advanced data analysis methods holds tremendous potential for driving progress in earthquake studies and damage assessment. 展开更多
关键词 Remote sensing Earthquake engineering Satellite imagery Machine learning dееp-lеarning mеthods
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An Overview of Dynamic Descriptions for Nanoscale Materials in Particulate Photocatalytic Systems from Spatiotemporal Perspectives
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作者 Jiawei Yan Zhidong Wei +4 位作者 Kai Takagi Masaya Motodate Zhi Jiang Chiaki Terashima Wenfeng Shangguan 《Nano-Micro Letters》 2025年第8期416-448,共33页
Particulate photocatalytic systems using nanoscale photocatalysts have been developed as an attractive promising route for solar energy utilization to achieve resource sustainability and environmental harmony.Dynamic ... Particulate photocatalytic systems using nanoscale photocatalysts have been developed as an attractive promising route for solar energy utilization to achieve resource sustainability and environmental harmony.Dynamic obstacles are considered as the dominant inhibition for attaining satisfactory energy-conversion efficiency.The complexity in light absorption and carrier transfer behaviors has remained to be further clearly illuminated.It is challenging to trace the fast evolution of charge carriers involved in transfer migration and interfacial reactions within a micro–nano-single-particle photocatalyst,which requires spatiotemporal high resolution.In this review,comprehensive dynamic descriptions including irradiation field,carrier separation and transfer,and interfacial reaction processes have been elucidated and discussed.The corresponding mechanisms for revealing dynamic behaviors have been explained.In addition,numerical simulation and modeling methods have been illustrated for the description of the irradiation field.Experimental measurements and spatiotemporal characterizations have been clarified for the reflection of carrier behavior and probing detection of interfacial reactions.The representative applications have been introduced according to the reported advanced research works,and the relationships between mechanistic conclusions from variable spatiotemporal measurements and photocatalytic performance results in the specific photocatalytic reactions have been concluded.This review provides a collective perspective for the full understanding and thorough evaluation of the primary dynamic processes,which would be inspired for the improvement in designing solar-driven energy-conversion systems based on nanoscale particulate photocatalysts. 展开更多
关键词 Dynamic description Particulate photocatalytic system Nanoscale photocatalyst Spatiotemporal characterization
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Inter-layer interference for multi-layered tight gas reservoir in the absence and presence of movable water 被引量:3
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作者 Tao Zhang Bin-Rui Wang +5 位作者 Yu-Long Zhao Lie-Hui Zhang Xiang-Yang Qiao Lei Zhang Jing-Jing Guo Hung Vo Thanh 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1751-1764,共14页
Due to the dissimilarity among different producing layers,the influences of inter-layer interference on the production performance of a multi-layer gas reservoir are possible.However,systematic studies of inter-layer ... Due to the dissimilarity among different producing layers,the influences of inter-layer interference on the production performance of a multi-layer gas reservoir are possible.However,systematic studies of inter-layer interference for tight gas reservoirs are really limited,especially for those reservoirs in the presence of water.In this work,five types of possible inter-layer interferences,including both absence and presence of water,are identified for commingled production of tight gas reservoirs.Subsequently,a series of reservoir-scale and pore-scale numerical simulations are conducted to quantify the degree of influence of each type of interference.Consistent field evidence from the Yan'an tight gas reservoir(Ordos Basin,China)is found to support the simulation results.Additionally,suggestions are proposed to mitigate the potential inter-layer interferences.The results indicate that,in the absence of water,commingled production is favorable in two situations:when there is a difference in physical properties and when there is a difference in the pressure system of each layer.For reservoirs with a multi-pressure system,the backflow phenomenon,which significantly influences the production performance,only occurs under extreme conditions(such as very low production rates or well shut-in periods).When water is introduced into the multi-layer system,inter-layer interference becomes nearly inevitable.Perforating both the gas-rich layer and water-rich layer for commingled production is not desirable,as it can trigger water invasion from the water-rich layer into the gas-rich layer.The gas-rich layer might also be interfered with by water from the neighboring unperforated water-rich layer,where the water might break the barrier(eg weak joint surface,cement in fractures)between the two layers and migrate into the gas-rich layer.Additionally,the gas-rich layer could possibly be interfered with by water that accumulates at the bottom of the wellbore due to gravitational differentiation during shut-in operations. 展开更多
关键词 Tight gas Comingled production INTERFERENCE Two-phase flow Water blocking
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Research on the structures and features of netizens' demand for popular science: A search data perspective 被引量:1
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作者 Liming Wang Qi Zhong 《Cultures of Science》 2019年第2期129-150,共22页
Netizens' demand for popular science could be seen as one important social representation of the public demand for science popularization in the information age. Based on the information searching behaviour of net... Netizens' demand for popular science could be seen as one important social representation of the public demand for science popularization in the information age. Based on the information searching behaviour of netizens, this paper uses two indicators(demand strength and breadth)to analyse and describe netizens' demand for popular science. It examines the features, the intrinsic structure, the developing trends and group-to-group differences of netizens' demand for popular science. The results reflect younger, more mobile and fragmented tendencies in science communication in the information society, revealing the features of netizens' concerns and knowledge of popular science. 展开更多
关键词 Netizens’demand for popular science Baidu Index demand strength demand breadth
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Theory for Charge Density Wave and Orbital-Flux State in Antiferromagnetic Kagome Metal FeGe 被引量:1
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作者 马海洋 殷嘉鑫 +1 位作者 M.Zahid Hasan 刘健鹏 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第4期90-104,共15页
We theoretically study the charge order and orbital magnetic properties of a new type of antiferromagnetic kagome metal FeGe.Based on first-principles density functional theory calculations,we study the electronic str... We theoretically study the charge order and orbital magnetic properties of a new type of antiferromagnetic kagome metal FeGe.Based on first-principles density functional theory calculations,we study the electronic structures,Fermi-surface quantum fluctuations,as well as phonon properties of the antiferromagnetic kagome metal FeGe.It is found that charge density wave emerges in such a system due to a subtle cooperation between electron-electron interactions and electron–phonon couplings,which gives rise to an unusual scenario of interaction-triggered phonon instabilities,and eventually yields a charge density wave(CDW)state.We further show that,in the CDW phase,the ground-state current density distribution exhibits an intriguing star-of-David pattern,leading to flux density modulation.The orbital fluxes(or current loops)in this system emerge as a result of the subtle interplay between magnetism,lattice geometries,charge order,and spin-orbit coupling(SOC),which can be described by a simple,yet universal,tight-binding theory including a Kane-Mele-type SOC term and a magnetic exchange interaction.We further study the origin of the peculiar step-edge states in FeGe,which sheds light on the topological properties and correlation effects in this new type of kagome antiferromagnetic material. 展开更多
关键词 interaction PHONON ORBITAL
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For a new era of symbiosis:The 81st World Science Fiction Convention
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作者 Lifen Yao 《Cultures of Science》 2023年第4期363-367,共5页
1.Introduction Founded in 1939,the World Science Fiction Convention(Worldcon)is an annual event that has been held 81 times to date.It is a world-famous,long-standing,large-scale and influential sci-fi cultural event ... 1.Introduction Founded in 1939,the World Science Fiction Convention(Worldcon)is an annual event that has been held 81 times to date.It is a world-famous,long-standing,large-scale and influential sci-fi cultural event organized by the World Science Fiction Society. 展开更多
关键词 World Science Fiction Society Cultural Event SYMBIOSIS science fiction Worldcon World Science Fiction Convention INNOVATION
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Insights from China for a global perspective on a responsible science–society relationship
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作者 Anne M Dijkstra Lin Yin 《Cultures of Science》 2019年第1期65-76,共12页
Ensuring that science meets the needs of society and does so responsibly is a key aim of current European policymaking.Under the label of‘responsible research and innovation',European Union projects,such as the N... Ensuring that science meets the needs of society and does so responsibly is a key aim of current European policymaking.Under the label of‘responsible research and innovation',European Union projects,such as the NUCLEUS project,have been funded to both study and stimulate practices for the development of responsible science–society relationships.The NUCLEUS project aims to define a broader cultural,international and enriched perspective on what a responsible science–society relationship entails.In this paper,findings from a comparative case study in China are presented.Practices are analysed at the conceptual,governmental,institutional and individual levels.Our findings show that social responsibility is the key to the science–society relationship,and that science popularization is a means to enhance scientific literacy. 展开更多
关键词 Responsible research and innovation science popularization science-society relationship social responsibility
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A virtual thermometer for ultrahigh-temperature-pressure experiments in a large-volume press
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作者 Bingtao Feng Longjian Xie +8 位作者 Xuyuan Hou Shucheng Liu Luyao Chen Xinyu Zhao Chenyi Li Qiang Zhou Kuo Hu Zhaodong Liu Bingbing Liu 《Matter and Radiation at Extremes》 SCIE EI CSCD 2024年第4期98-110,共13页
Ultrahigh-temperature-pressure experiments are crucial for understanding the physical and chemical properties of matter.The recent development of boron-doped diamond(BDD)heaters has made such melting experiments possi... Ultrahigh-temperature-pressure experiments are crucial for understanding the physical and chemical properties of matter.The recent development of boron-doped diamond(BDD)heaters has made such melting experiments possible in large-volume presses.However,estimates of temperatures above 2600 K and of the temperature distributions inside BDD heaters are not well constrained,owing to the lack of a suitable thermometer.Here,we establish a three-dimensional finite element model as a virtual thermometer to estimate the temperature and temperature field above 2600 K.The advantage of this virtual thermometer over those proposed in previous studies is that it considers both alternating and direct current heating modes,the actual sizes of cell assemblies after compression,the effects of the electrode,thermocouple and anvil,and the heat dissipation by the pressure-transmitting medium.The virtual thermometer reproduces the power-temperature relationships of ultrahigh-temperature-pressure experiments below 2600 K at press loads of 2.8-7.9 MN(~19 to 28 GPa)within experimental uncertainties.The temperatures above 2600 K predicted by our virtual thermometer are within the uncertainty of those extrapolated from power-temperature relationships below 2600 K.Furthermore,our model shows that the temperature distribution inside a BDD heater(19-26 K/mm along the radial direction and<83 K/mm along the longitudinal direction)is more homogeneous than those inside conventional heaters such as graphite or LaCrO_(3) heaters(100-200 K/mm).Our study thus provides a reliable virtual thermometer for ultrahigh-temperature experiments using BDD heaters in Earth and material sciences. 展开更多
关键词 VIRTUAL ultrahigh SIZES
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Science history and science communication:A preliminary exploration of science-history texts in Science Pictorial(1933–1949)
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作者 Meifang Zhang Mengge Wang Fangang Meng 《Cultures of Science》 2024年第4期247-256,共10页
As one of China's oldest and most comprehensive popular-science journals, Science Pictorial has long been dedicated to promoting science and enhancing public scientific literacy. This paper presents a textual anal... As one of China's oldest and most comprehensive popular-science journals, Science Pictorial has long been dedicated to promoting science and enhancing public scientific literacy. This paper presents a textual analysis of the science-history content in the journal from 1933 to 1949, exploring how mass media disseminated the knowledge of science history during the Republic of China era and the societal perceptions it reflected. The findings reveal that Science Pictorial's approach to science history reflects an empirical view of science and a progressive view of science history embraced by science communicators. This highlights the strong sense of national crisis felt by Chinese intellectuals at the time, the broad impact of scientific thinking and their deep respect for the scientific community. From a historiographical perspective, we propose that research on science communication should consider the communicators' views on science and science history, as well as the ideological motivations and social forces shaping these views. This approach enables us to tackle more fundamental questions, such as why we conduct science communication and what we should communicate. We also suggest that science communicators should not only disseminate scientific knowledge but also account for the historical and cultural contexts of science. Ideally, they should develop a strong foundation in the historiography of science to help build a comprehensive framework for science communication. 展开更多
关键词 Science Pictorial history of science science communication historiography of science
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Bistable switch molecule DPACdCl_(4) showing four physical channels and high phase transition temperature
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作者 Ying-Yu Zhang Jia-Qi Luo +4 位作者 Yan Han Wan-Ying Zhang Yi Zhang Hai-Feng Lu Da-Wei Fu 《Chinese Chemical Letters》 2025年第1期591-596,共6页
Multiple switchable physical channels within one material or device,encompassing optical,electrical,thermal,and mechanical pathways,can enable multifunctionality in mechanical-thermal-opto-electronic applications.Achi... Multiple switchable physical channels within one material or device,encompassing optical,electrical,thermal,and mechanical pathways,can enable multifunctionality in mechanical-thermal-opto-electronic applications.Achieving integrated encryption and enhanced performance in storage and sensing presents a formidable challenge in the synthesis and functionality of new materials.In an effort to overcome the complexities associated with these multiple physical functions,this study investigates the large-size crystal of DPACdCl_(4)(DPA=diisopropylammonium),revealing significant features in rare multi-channel switches.This compound demonstrates the ability to switch between"OFF/0"and"ON/1"states in the mechanical-thermal-opto-electronic channels.Consequently,DPACd Cl_(4)possesses four switchable physical channels,characterized by a higher phase transition temperature of 440.7 K and a competitive piezo-electric coefficient of 46 pC/N.Furthermore,solid-state NMR analysis indicates that thermally activated molecular vibrations significantly contribute to its multifunctional switching capabilities. 展开更多
关键词 Organic-inorganic hybrid Phase transition Crystal PEROVSKITE PIEZOELECTRICITY
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Exploring superconductivity in dynamically stable carbon-boron clathrates trapping molecular hydrogen
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作者 Akinwumi Akinpelu Mangladeep Bhullar +1 位作者 Timothy A.Strobel Yansun Yao 《Chinese Physics B》 2025年第3期131-140,共10页
The recent discovery of type-Ⅶboron-carbon clathrates with calculated superconducting transition temperatures approaching~100 K has sparked interest in exploring new conventional superconductors that may be stabilize... The recent discovery of type-Ⅶboron-carbon clathrates with calculated superconducting transition temperatures approaching~100 K has sparked interest in exploring new conventional superconductors that may be stabilized at ambient pressure.The electronic structure of the clathrate is highly tunable based on the ability to substitute different metal atoms within the cages,which may also be large enough to host small molecules.Here we introduce molecular hydrogen(H_(2))within the clathrate cages and investigate its impact on electron-phonon coupling interactions and the superconducting transition temperature(T_(c)).Our approach involves combining molecular hydrogen with the new diamond-like covalent framework,resulting in a hydrogen-encapsulated clathrate,(H_(2))B_(3)C_(3).A notable characteristic of(H_(2))B_(3)C_(3)is the dynamic behavior of the H_(2)molecules,which exhibit nearly free rotations within the B-C cages,resulting in a dynamic structure that remains cubic on average.The static structure of(H_(2))B_(3)C_(3)(a snapshot in its dynamic trajectory)is calculated to be dynamically stable at ambient and low pressures.Topological analysis of the electron density reveals weak van der Waals interactions between molecular hydrogen and the B-C cages,marginally influencing the electronic structure of the material.The electron count and electronic structure calculations indicate that(H_(2))B_(3)C_(3)is a hole conductor,in which H_(2)molecules donate a portion of their valence electron density to the metallic cage framework.Electron-phonon coupling calculation using the Migdal-Eliashberg theory predicts that(H_(2))B_(3)C_(3)possesses a T_(c) of 46 K under ambient pressure.These results indicate potential for additional light-element substitutions within the type-Ⅶclathrate framework and suggest the possibility of molecular hydrogen as a new approach to optimizing the electronic structures of this new class of superconducting materials. 展开更多
关键词 SUPERCONDUCTIVITY electronic structure density functional theory molecular dynamics
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Modeling and Estimating Soybean Leaf Area Index and Biomass Using Machine Learning Based on Unmanned Aerial Vehicle-Captured Multispectral Images
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作者 Sadia Alam Shammi Yanbo Huang +5 位作者 Weiwei Xie Gary Feng Haile Tewolde Xin Zhang Johnie Jenkins Mark Shankle 《Phyton-International Journal of Experimental Botany》 2025年第9期2745-2766,共22页
Crop leaf area index(LAI)and biomass are two major biophysical parameters to measure crop growth and health condition.Measuring LAI and biomass in field experiments is a destructive method.Therefore,we focused on the ... Crop leaf area index(LAI)and biomass are two major biophysical parameters to measure crop growth and health condition.Measuring LAI and biomass in field experiments is a destructive method.Therefore,we focused on the application of unmanned aerial vehicles(UAVs)in agriculture,which is a cost and labor-efficientmethod.Hence,UAV-captured multispectral images were applied to monitor crop growth,identify plant bio-physical conditions,and so on.In this study,we monitored soybean crops using UAV and field experiments.This experiment was conducted at theMAFES(Mississippi Agricultural and Forestry Experiment Station)Pontotoc Ridge-Flatwoods Branch Experiment Station.It followed a randomized block design with five cover crops:Cereal Rye,Vetch,Wheat,MC:mixed Mustard and Cereal Rye,and native vegetation.Planting was made in the fall,and three fertilizer treatments were applied:Synthetic Fertilizer,Poultry Litter,and none,applied before planting the soybean,in a full factorial combination.We monitored soybean reproductive phases at R3(initial pod development),R5(initial seed development),R6(full seed development),and R7(initial maturity)and used UAV multispectral remote sensing for soybean LAI and biomass estimations.The major goal of this study was to assess LAI and biomass estimations from UAV multispectral images in the reproductive stages when the development of leaves and biomass was stabilized.Wemade about fourteen vegetation indices(VIs)fromUAVmultispectral images at these stages to estimate LAI and biomass.Wemodeled LAI and biomass based on these remotely sensed VIs and ground-truth measurements usingmachine learning methods,including linear regression,Random Forest(RF),and support vector regression(SVR).Thereafter,the models were applied to estimate LAI and biomass.According to the model results,LAI was better estimated at the R6 stage and biomass at the R3 stage.Compared to the other models,the RF models showed better estimation,i.e.,an R^(2) of about 0.58–0.68 with an RMSE(rootmean square error)of 0.52–0.60(m^(2)/m^(2))for the LAI and about 0.44–0.64 for R^(2) and 21–26(g dry weight/5 plants)for RMSE of biomass estimation.We performed a leave-one-out cross-validation.Based on cross-validatedmodels with field experiments,we also found that the R6 stage was the best for estimating LAI,and the R3 stage for estimating crop biomass.The cross-validated RF model showed the estimation ability with an R^(2) about 0.25–0.44 and RMSE of 0.65–0.85(m^(2)/m^(2))for LAI estimation;and R^(2) about 0.1–0.31 and an RMSE of about 28–35(g dry weight/5 plants)for crop biomass estimation.This result will be helpful to promote the use of non-destructive remote sensing methods to determine the crop LAI and biomass status,which may bring more efficient crop production and management. 展开更多
关键词 SOYBEAN LAI BIOMASS reproductive growth stage UAV multispectral imaging machine learning
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Assessing fiber quality variability among modern upland cotton cultivars and incorporating it into the GOSSYM-based fiber quality simulation model
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作者 BEEGUM Sahila HASSAN Muhammad Adeel +2 位作者 REDDY Krishna N. REDDY Vangimalla REDDY Kambham Raja 《Journal of Cotton Research》 2025年第2期213-227,共15页
Background GOSSYM is a mechanistic,process-based cotton model that can simulate cotton crop growth and development,yield,and fiber quality.Its fiber quality module was developed based on controlled experiments explici... Background GOSSYM is a mechanistic,process-based cotton model that can simulate cotton crop growth and development,yield,and fiber quality.Its fiber quality module was developed based on controlled experiments explicitly conducted on the Texas Marker^(-1)(TM1)variety,potentially making its functional equations more aligned with this cultivar.To assess the model’s broader applicability,this study analyzed fiber quality data from 40 upland cotton cultivars,including TM1.The measured fiber quality from all cultivars was then compared with the modelsimulated fiber quality.Results Among the 40 upland cultivars,fiber strength varied from 28.4 cN·tex^(-1) to 34.6 cN·tex^(-1),fiber length ranged from 27.1 mm to 33.3 mm,micronaire value ranged from 2.7 to 4.6,and length uniformity index varied from 82.3%to 85.5%.The model simulated fiber quality closely matched the measured values for TM1,with the absolute percentage error(APE)being less than 0.92%for fiber strength,fiber length,and length uniformity index and 4.7%for micronaire.However,significant differences were observed for the other cultivars.The Pearson correlation coefficient(r)between the measured and simulated values was negative for all fiber quality traits,and Wilmotts’s index of agreement(WIA)was below 0.45,indicating a strong model bias toward TM1 without incorporating cultivar-specific parameters.After incorporating cultivar-specific parameters,the model’s performance improved significantly,with an average r-value of 0.84 and WIA of 0.88.Conclusions The adopted methodology and estimated cultivar-specific parameters improved the model’s simulation accuracy.This approach can be applied to newer cotton cultivars,enhancing the GOSSYM model’s utility and its applicability for agricultural management and policy decisions. 展开更多
关键词 COTTON GOSSYM Crop modeling Fiber quality Cultivar-specific parameter
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High-throughput phenotyping discovers new stable loci controlling senescence rate in bread wheat
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作者 Lei Li Jindong Liu +10 位作者 Muhammad Adeel Hassan Duoxia Wang Keyi Wang Shuaipeng Fei Jianqi Zeng Awais Rasheed Xianchun Xia Zhonghu He Yong He Yong Zhang Yonggui Xiao 《The Crop Journal》 2025年第4期1168-1177,共10页
Non-destructive time-series assessment of chlorophyll content in flag-leaf(FLC)accurately mimics the senescence rate and the identification of genetic loci associated with senescence provides valuable knowledge to imp... Non-destructive time-series assessment of chlorophyll content in flag-leaf(FLC)accurately mimics the senescence rate and the identification of genetic loci associated with senescence provides valuable knowledge to improve yield stability under stressed environments.In this study,we employed both unmanned aerial vehicles(UAVs)equipped with red–green–blue(RGB)camera and ground-based SPAD-502 instrument to conduct temporal phenotyping of senescence.A total of 262 recombinant inbred lines derived from the cross of Zhongmai 578/Jimai 22 were evaluated for senescence-related traits across three environments,spanning from heading to 35 d post-anthesis.The manual senescence rate(MSR)was quantified using the FLC and the active accumulated temperature,and UAV derived vegetation index were utilized to assess the stay-green rate(USG)facilitating the identification of senescent and stay-green lines.Results indicated that higher senescence rates significantly impacted grain yield,primarily by influencing thousand-kernel weight,and plant height.Quantitative trait loci(QTL)mapping for FLC,USG,and MSR using the 50K SNP array identified 38 stable loci associated with RGB-based vegetation indices and senescence-related traits:among which 19 loci related to senescence traits from UAV and FLC were consistently detected across at least two growth stages,with nine loci likely representing novel QTL.This study highlights the potential of UAV-based high-throughput phenotyping and phenology in identifying critical loci associated with senescence rates in wheat,validating the relationship between senescence rates and yield-related traits in wheat,offering valuable opportunities for gene discovery and significant applications in breeding programs. 展开更多
关键词 Aerial digital imaging Active accumulated temperature CHLOROPHYLL QTL Senescence rate Common wheat
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The Mg-carbonate-Fe interaction:Implication for the fate of subducted carbonates and formation of diamond in the lower mantle 被引量:4
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作者 Naira S.Martirosyan Konstantin D. Litasov +4 位作者 Sergey S. Lobanov Alexander F. Goncharov Anton Shatskiy Hiroaki Ohfuji Vitali Prakapenka 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第4期1449-1458,共10页
The fate of subducted carbonates in the lower mantle and at the core-mantle boundary was modelled via experiments in the MgCO3-Fe^0 system at 70-150 GPa and 800-2600 Kin a laser-heated diamond anvil cell.Using in situ... The fate of subducted carbonates in the lower mantle and at the core-mantle boundary was modelled via experiments in the MgCO3-Fe^0 system at 70-150 GPa and 800-2600 Kin a laser-heated diamond anvil cell.Using in situ synchrotro n X-ray diffraction and ex situ transmission electron microscopy we show that the reduction of Mg-carbonate can be exemplified by:6 MgCO3+19 Fe=8 FeO+10(Mg0.6Fe^0.4)O+Fe7 C3+3 C.The presented results suggest that the interaction of carbonates with Fe^0 or Fe^0-bearing rocks can produce Fe-carbide and diamond,which can accumulate in the D"region,depending on its carbon to Fe ratio.Due to the sluggish kinetics of the transformation,diamond can remain metastable at the core-mantle boundary(CMB)unless it is in a direct contact with Fe-metal.In addition,it can be remobilized by redox melting accompanying the generation of mantle plumes. 展开更多
关键词 Deep carbon cycle CARBONATE CARBIDE High pressure Redox reaction
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Outcome of the efficacy of Chinese herbal medicine for functional constipation:A systematic review and meta-analysis 被引量:6
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作者 Zipan Lyu Yibo Fan +3 位作者 Yang Bai Tao Liu Linda LD Zhong Hui-Feng Liang 《World Journal of Clinical Cases》 SCIE 2022年第15期4856-4877,共22页
BACKGROUND Functional constipation(FC)is a common and chronic gastrointestinal disease and its treatment remains challenging.AIM To evaluate the efficacy and safety of Chinese herbal medicine(CHM)on efficacy rate,glob... BACKGROUND Functional constipation(FC)is a common and chronic gastrointestinal disease and its treatment remains challenging.AIM To evaluate the efficacy and safety of Chinese herbal medicine(CHM)on efficacy rate,global symptoms,bowel movements and the Bristol Stool Scale score in patients with FC by summarizing current available randomized controlled trials(RCTs).METHODS RCTs with CHM to treat FC were identified by a systematic search of six databases from inception to October 20,2020.Two independent reviewers assessed the quality of the included articles and extracted data.Meta-analyses were performed to odds ratio(OR),mean differences(MD)and 95%confidence interval(CI)using random-effects models.Subgroup analyses and sensitivity analyses were used to explore and interpret the sources of heterogeneity.The funnel plot,Begg’s test and Egger’s test were used to detect publication bias.RESULTS Ninety-seven studies involving 8693 patients were included in this work.CHM was significantly associated with a higher efficacy rate(OR:3.62,95%CI:3.19-4.11,P<0.00001)less severe global symptoms(OR:4.03,95%CI:3.49-4.65,P<0.00001)compared with control treatment,with the low heterogeneity between studies(I2=0%,P=0.76).CHM was also associated with more frequent bowel movements(MD 0.83,95%CI:0.67-0.98,P<0.00001),a lower score on the Bristol Stool Scale(OR:1.63,95%CI:1.15-2.32,P<0.006),and a not significant recurrence rate(OR:0.47,95%CI:0.22-0.99,P=0.05).No serious adverse effects of CHM were reported.CONCLUSION In this meta-analysis,we found that CHM may have potential benefits in increasing the number of bowel movements,improving stool characteristics and alleviating global symptoms in FC patients.However,a firm conclusion could not be reached because of the poor quality of the included trials.Further trials with higher quality are required. 展开更多
关键词 Functional constipation Chinese herbal medicine EFFICACY Systematic review META-ANALYSIS
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