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一款高效率、三模式、低EMI的同步整流型Buck DC-DC转换器
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作者 丁世翔 郝松茂 石春琦 《华东师范大学学报(自然科学版)》 北大核心 2026年第2期82-94,共13页
基于国产55 nm CMOS(Complementary Metal-Oxide-Semiconductor)工艺,设计了一款适合低电磁干扰(Electromagnetic Interference, EMI)应用,峰值效率为92.95%的三模式Buck DC-DC转换器芯片.在不同负载条件下,该DC-DC芯片可以在脉冲宽度调... 基于国产55 nm CMOS(Complementary Metal-Oxide-Semiconductor)工艺,设计了一款适合低电磁干扰(Electromagnetic Interference, EMI)应用,峰值效率为92.95%的三模式Buck DC-DC转换器芯片.在不同负载条件下,该DC-DC芯片可以在脉冲宽度调制(Pulse Width Modulation, PWM)、脉冲频率调制(Pulse Frequency Modulation, PFM)以及跳脉冲调制(Pulse Skip Modulation, PSM)间无缝切换,优化了效率与纹波表现.芯片基于扩频调制技术(Spread-Spectrum Frequency Modulation, SSFM),通过实现35%频率抖动的扩频调制,使得Buck转换器的输出电压频谱峰值降低22 dB,显著抑制了DC-DC转换器产生的电磁干扰. 展开更多
关键词 Buck转换器 emi 扩频调制 多工作模式 高效率
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适应新标准的EMI接收机校准方法的研究
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作者 朱明星 孟令刚 《计量与测试技术》 2026年第1期94-98,共5页
CISPR 16-1-1新标准对EMI接收机的性能参数作出了明确规定,而现行国家计量技术规范无法满足该要求。本文通过对新标准的研究,提出总选择性与不同检波器下的脉冲响应特性两项关键参数的校准方法,并通过实验进行验证,使EMI接收机的计量方... CISPR 16-1-1新标准对EMI接收机的性能参数作出了明确规定,而现行国家计量技术规范无法满足该要求。本文通过对新标准的研究,提出总选择性与不同检波器下的脉冲响应特性两项关键参数的校准方法,并通过实验进行验证,使EMI接收机的计量方案更加完整有效,并适应新标准的要求。 展开更多
关键词 emi接收机 总选择性 脉冲响应 校准方法
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元器件互耦影响下的EMI滤波器衰减特性分析
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作者 徐舟江 舒亮 +3 位作者 江闽 邓祎健 王传奇 包晓忠 《机电工程技术》 2026年第2期11-18,共8页
作为电磁干扰抑制的核心部分,EMI滤波器的高频衰减能力本质上受制于元器件之间的电磁耦合效应。针对这一效应,通过建立多维度耦合模型,系统解析了滤波器性能衰减的机理,旨在为滤波器系统的优化设计提供兼具理论深度与工程实用价值的解... 作为电磁干扰抑制的核心部分,EMI滤波器的高频衰减能力本质上受制于元器件之间的电磁耦合效应。针对这一效应,通过建立多维度耦合模型,系统解析了滤波器性能衰减的机理,旨在为滤波器系统的优化设计提供兼具理论深度与工程实用价值的解决方案。利用Q3D电磁仿真软件构建了滤波电容器寄生电感的等效模型,进而分析了电容器间的磁场耦合效应对差模衰减的影响。建立了共模扼流圈等磁性元件的三维等效模型,并考虑接地层电感的高频耦合机制,系统研究了寄生参数和电磁耦合效应对滤波器衰减特性的作用规律。针对拓扑结构复杂的三相EMI滤波器,识别其关键耦合路径,并建立了共模等效电路模型。经实验与仿真验证,在10 kHz~30 MHz的范围内误差小于6 dB,证明了模型的有效性。 展开更多
关键词 emi滤波器 3D建模 耦合效应 衰减特性
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“英语+审计”EMI课程教学现状与优化路径
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作者 王晨曦 《英语广场》 2026年第2期78-81,共4页
为响应国家教育国际化战略,南京审计大学英语专业依托学校审计学科优势,开设“英语+审计”EMI课程。本研究以该课程为个案,通过问卷调查、半结构化访谈等方法,系统探究课程实施中的现实困境。研究发现,当前课程存在学科教师与语言教师... 为响应国家教育国际化战略,南京审计大学英语专业依托学校审计学科优势,开设“英语+审计”EMI课程。本研究以该课程为个案,通过问卷调查、半结构化访谈等方法,系统探究课程实施中的现实困境。研究发现,当前课程存在学科教师与语言教师合作机制不畅、学生专业基础知识掌握不扎实等问题。基于此,本文提出构建EMI师资储备库、设计融合式课程体系等优化路径,为高校外语专业EMI课程建设提供参考。 展开更多
关键词 英语专业 审计学 emi课程
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Petrography and geochemistry of the Dupi Tila formation:Implications for depositional environment and tectonics
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作者 Ummae Habiba Sultana Md Shofiqul Islam +5 位作者 Yesmin Nahar Jolly K.M.Mamun Shirin Akter Muhammad Omar Faruk Maliha Anzuman Md Masud Karim 《Acta Geochimica》 2025年第4期740-758,共19页
A comprehensive examination of detrital sandstone modes from the Sylhet Trough reveals a diverse range of sub-lithic to sub-feldspathic quartz arenites.Soil samples were gathered from Dupi Gaon(Jaintiapur)in Banglades... A comprehensive examination of detrital sandstone modes from the Sylhet Trough reveals a diverse range of sub-lithic to sub-feldspathic quartz arenites.Soil samples were gathered from Dupi Gaon(Jaintiapur)in Bangladesh,followed by a thorough analysis using field examination,X-ray diffraction(XRD),X-ray fluorescence(XRF),petrography,and heavy mineral concentration analyses.Field observations revealed the soil sample varying from white to yellowish to variegated,with thicknesses ranging from 15 cm to about 4 m,and exhibiting moderate softness.XRF analysis revealed significant SiO_(2),Al_(2)O_(3),and Fe_(2)O_(3)levels in the samples,with zirconium(Zr)and copper(Cu)showing consistently high concentrations.XRD analysis identified quartz as predominant,along with muscovite,biotite,and accessory minerals like rutile and magnetite.Petrographic analysis highlighted quartz as dominant,with fractures suggesting tectonic influences,while heavy mineral separation techniques identified zircon,garnet,goethite,rutile,and magnetite.These findings provide insights into sediment provenance,depositional processes,and environ-mental conditions during the formation of the Dupi Tila Formation.The comprehensive geochemical data of the entire rock indicates that most of the sediments originated from felsic igneous sources,and also suggests a moderate to high level of weathering in the source region.Overall,the analyses suggested an in situ origin of the Dupi Tila Formation,with parent materials being predominantly detrital rather than authigenic,supported by the presence of detrital quartz and an assessment of the depositional environment,providing insights into the geological conditions of the era and potential modes of sediment transportation. 展开更多
关键词 PETROGRAPHY GEOCHemiSTRY Depositional environment Detrital sandstone Dupi Tila formation
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Modulating the coordination environment of cobalt porphyrins for enhanced electrochemical nitrite reduction to ammonia
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作者 Jingwei Han Hai Sun +5 位作者 Fengkun Tian Wenwen Zhang Zonghang Zhang Ping She Jun-Sheng Qin Heng Rao 《Carbon Energy》 2025年第1期25-35,共11页
Electrocatalytic reduction of nitrate pollutants to produce ammonia offers an effective approach to realizing the artificial nitrogen cycle and replacing the energyintensive Haber-Bosch process.Nitrite is an important... Electrocatalytic reduction of nitrate pollutants to produce ammonia offers an effective approach to realizing the artificial nitrogen cycle and replacing the energyintensive Haber-Bosch process.Nitrite is an important intermediate product in the reduction of nitrate to ammonia.Therefore,the mechanism of converting nitrite into ammonia warrants further investigation.Molecular cobalt catalysts are regarded as promising for nitrite reduction reactions(NO_(2)^(−)RR).However,designing and controlling the coordination environment of molecular catalysts is crucial for studying the mechanism of NO_(2)^(−)RR and catalyst design.Herein,we develop a molecular platform of cobalt porphyrin with three coordination microenvironments(Co-N_(3)X_(1),X=N,O,S).Electrochemical experiments demonstrate that cobalt porphyrin with O coordination(CoOTPP)exhibits the lowest onset potential and the highest activity for NO_(2)^(−)RR in ammonia production.Under neutral,nonbuffered conditions over a wide potential range(−1.0 to−1.5 V versus AgCl/Ag),the Faradaic efficiency of nearly 90%for ammonia was achieved and reached 94.5%at−1.4 V versus AgCl/Ag,with an ammonia yield of 6,498μgh^(−1)and a turnover number of 22,869 at−1.5V versus AgCl/Ag.In situ characterization and density functional theory calculations reveal that modulating the coordination environment alters the electron transfer mode of the cobalt active center and the charge redistribution caused by the break of the ligand field.Therefore,this results in enhanced electrochemical activity for NO_(2)^(−)RR in ammonia production.This study provides valuable guidance for designing adjustments to the coordination environment of molecular catalysts to enhance catalytic activity. 展开更多
关键词 coordination environment electrocatalytic nitrite reduction heterogeneous catalysis molecular catalyst
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Restrict Toxic Emissions from Internal Combustion Engines to Protect the Environment by Using Diesel Fuel Mixed with Vegetable Oil
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作者 Trung Dinh Pham Nghia Duc Mai Tuan Duc Ho 《Journal of Environmental & Earth Sciences》 2025年第2期62-75,共14页
For internal combustion engines,engines installed for transport ships,cargo ships,and fishing vessels are mainly diesel engines.The number of engines is increasing due to the development of the maritime and seafood ex... For internal combustion engines,engines installed for transport ships,cargo ships,and fishing vessels are mainly diesel engines.The number of engines is increasing due to the development of the maritime and seafood exploitation sectors.Therefore,the high demand for petroleum fuels increases environmental pollution due to engine emissions.Reducing environmental pollution from the combustion of petroleum fuels has become a concern worldwide,especially for internal combustion engines.The exhaust gases from the engine contain harmful substances such as soot and nitrogen oxides(NO_(x)).Fuels with higher carbon content generate more soot when burned.In contrast,biofuels have low carbon and sulfur content and supply ample oxygen,which helps to reduce soot formation.For these reasons,biofuels are encouraged as alternative fuels to petroleum.Vegetable oil is one of the primary raw materials for biofuel production.This study presents a mixture of diesel and vegetable oil utilized as fuel for fishing vessels’diesel engines.The results of experimental research on a fishing vessel’s 4CHE Yanmar diesel engine when using diesel fuel mixed with coconut oil(B15,15%coconut oil,and 85%diesel)show that increasing B15 fuel injection pressure by about 10–15%compared with diesel fuel injection pressure reduces the engine’s soot emissions and increases power compared to unadjusted.This solution contributes to reducing environmental pollution from engine emissions. 展开更多
关键词 Vegetable Oil Fuel Injection Pressure SOOT NO_(x) environment
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GeoChip-Based Microbial Functions in Biogeochemical Cycles and Their Responses to Environmental Factors in Tengchong Hot Springs
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作者 Muhammad Inayat Ullah Khan Liuqin Huang +3 位作者 Geng Wu Jian Yang Xiangyu Guan Hongchen Jiang 《Journal of Earth Science》 2025年第2期382-394,共13页
Microorganisms actively participate in biogeochemical cycling processes and play a crucial role in maintaining the dynamic balance of hot spring ecosystems.However,the distribution of microbial functional genes and th... Microorganisms actively participate in biogeochemical cycling processes and play a crucial role in maintaining the dynamic balance of hot spring ecosystems.However,the distribution of microbial functional genes and their influencing factors in hot springs remain largely unclear.Therefore,this study investigated the microbial functional genes and their potential for controlling biogeochemical cycles(C,N,S,and P) in the hot Springs of Tengchong,China,using the Geochip method,a functional gene microarray technology.The examined hot springs have very different microbial functional genes.A total of 22 736 gene probe signals were identified,belonging to 567 functional genes and associated with 15 ecological functions,mainly involving stress response,carbon cycle,nitrogen cycle,sulfur cycle,phosphorus cycle and energy processes.The amyA,narG,dsrA and ppx genes were most abundant in carbon,nitrogen,sulfur and phosphorus cycles,respectively,and were significantly correlated with pH,temperature and SO_(4)^(2-).The diversity and abundance of detected gene probes were negatively correlated with temperature.The α-diversity(i.e.,Shannon index) was high at low temperature and low pH.Molecular functional interactions revealed by the gene connectivity levels were negatively correlated with temperature,pH and SO_(4)^(2-).These results suggested that the abundance,diversity and interactions of microbial functional genes were significantly influenced by geochemical parameters.-In addition,some genera possessed functional genes related to carbon,nitrogen,sulfur,and phosphorus cycles and can synergistically control the biogeochemical cycles of carbon,nitrogen,sulfur and phosphorus.These findings provide new insights into the functional potentials of microorganisms to participate in biogeochemical cycles and their responses to environmental factors in hot springs. 展开更多
关键词 GeoChip functional genes biogeochemical cycles environmental factors microbial community GEOBIOLOGY environment geology
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基于共模电感的移动通信电源EMI滤波器设计与验证
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作者 芦婷 《移动信息》 2026年第3期37-39,共3页
针对移动通信电源系统中广泛存在的共模电磁干扰问题,文中设计了一种基于共模电感的T型EMI滤波器结构,采用双绕组磁耦合共模电感结合X/Y电容构成的对称拓扑,具备良好的共模干扰抑制能力。测试结果表明,该滤波器在1~10 MHz频段内最大插... 针对移动通信电源系统中广泛存在的共模电磁干扰问题,文中设计了一种基于共模电感的T型EMI滤波器结构,采用双绕组磁耦合共模电感结合X/Y电容构成的对称拓扑,具备良好的共模干扰抑制能力。测试结果表明,该滤波器在1~10 MHz频段内最大插入损耗超过40 dB,显著降低了电源输入端的共模干扰电平,同时在6 A负载电流下具备良好的热稳定性和长期可靠性,可有效满足通信电源设备对电磁兼容性的要求。 展开更多
关键词 emi滤波器 共模电感 电磁干扰 移动通信电源
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Parental cognitive ability effects on children’s logical reasoning ability:The mediating role of academic expectation and the family environment
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作者 Qing Wang Haiyan Xu Xuhuan Wang 《Journal of Psychology in Africa》 2025年第4期497-503,共7页
This study investigated the relationship between parental cognitive ability and child logical reasoning ability,and the role of academic expectation and family environment in that relationship.Based on the 2020 China ... This study investigated the relationship between parental cognitive ability and child logical reasoning ability,and the role of academic expectation and family environment in that relationship.Based on the 2020 China Family Panel Studies(CFPS)data,1491 children(girls ratio=53.78%;average grade=6.023 years,school grade standard deviation=1.825 years).Results following multiple regression model(OLS)show that the higher the parental cognitive ability,the higher the children’s logical reasoning ability.Secondly,parental academic expectation serves as a mediator between their cognitive ability and children’s logical reasoning ability for higher logical reasoning by children.Third,a possible family environment acts as a mediator in the relationship between parents’cognitive ability and children’s logical reasoning ability to be higher.We conclude from thesefindings that parents with high cognitive abilities can enhance their children’s logical reasoning skills not only by setting higher academic expectations,but also by cultivating a supportive family environment.Thesefindings imply a need for intervention to improve family quality of life to enhance children’s thinking abilities to optimize their academic learning. 展开更多
关键词 parental cognitive ability children’s logical reasoning ability academic expectation family environment intermediary role
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"Three Lines One Permit"environmental policy and its implementation assessment:a case study of Sichuan Province,China
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作者 LIU Yanguo WANG Li +5 位作者 YANG Ye LI Jingji PEI Xiangjun WANG Ziqin HE Yu CHEN An 《Journal of Mountain Science》 2026年第1期311-326,共16页
Integrated environmental management is important for sustainable development.Under China’s“Three Lines One Permit”(TLOP)policy,three types of management zones—priority protection,critical control,and general contr... Integrated environmental management is important for sustainable development.Under China’s“Three Lines One Permit”(TLOP)policy,three types of management zones—priority protection,critical control,and general control zones—are established based on the ecological red line,the lower-limit line for environmental quality,and the resource use line.Human activities are regulated through a permit system.Integrated and multifactorial protection of soil,plant,hydrological,and atmospheric elements is promoted at the regional level.A follow-up assessment contributes to the improvement of policy implementation and effectiveness.This study demonstrates the achievements of the TLOP policy in Sichuan Province.Results show that(1)276 protection zones have been established under the ecological red line,covering key ecosystems and protected areas to ensure environmental security.Under the lower-limit line,1,626 functional(priority,key,and general control)zones have been designated to regulate air,water,and soil quality,enhancing environmental capacity and pollution control.(2)Through the integration and merging of the three lines,1,128 integrated management zones have been established,including 375,625,and 128 priority protection,critical control,and general control zones,respectively.Each zone has its own list of environmental permits to regulate human activities according to different environmental protection and natural resource development regimes.(3)The design of the follow-up assessment index system was informed by regional primary functions and industrial structure.The index system for provinces and cities is structured around three primary indicators—implementation updating,application,and guarantees—and 15 secondary indicators.The system for critical control zones is structured around environmental access,management,and effectiveness and 14 secondary indicators.A stringent environmental zoning system has been established through the TLOP policy,thereby safeguarding environmental security,promoting harmonious existence between humans and nature,and supporting the vision of Beautiful China. 展开更多
关键词 Three Lines One Permit environment zoning system Ecological red line environment assessment Southwest China
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Climate Change Awareness:An Imperative for Environmental and Earth Stewardship
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作者 Elizabeth Akpanke Odey Anthony Okon Ben +10 位作者 Alex Abang Ebu Edor John Edor Edem Essien Udoaka Eni Eja Alobo Miebaka Nabiebu Gabriel Etim-Ben Inyang Edet Louis Ajom Aboh James Ajang Ellah Timothy Ogbang Osmond Otora Agbor Iorparegh Aer 《Research in Ecology》 2026年第1期67-78,共12页
The accelerating impacts of climate change,rising temperatures,extreme weather events,and biodiversity loss underscore the urgent need for widespread public awareness.This research explores why climate change awarenes... The accelerating impacts of climate change,rising temperatures,extreme weather events,and biodiversity loss underscore the urgent need for widespread public awareness.This research explores why climate change awareness is not just beneficial but essential for effective environmental stewardship and the long-term health of our planet.The research proffers informed communities,encouraging sustainable practices,and driving policy advocacy,awareness serves as a model for collective action.This call to consciousness challenges individuals,institutions,and nations to recognize their role in shaping a resilient,sustainable future for the Earth.Methodology adopted in this research is a mixed-method design,involving both qualitative and quasi-experimental designs,which engages the use of focus group discussions and oral interviews to explore deeper insights into perceptions,biodiversity loss consciousness,and environmental depletion challenges.Also,applicable under the qualitative method is the secondary data collection mode,namely,reports from IPCC,government policy documents,and existing literature related to the context of the research.The empirical and scientific data analysis was presented from the data collected and was coded and subjected to analysis using a paired samples t-test.The study is grounded on the theory of“Value-Belief-Norm”(VBN)developed by Stern et al.The VBN theory posits that individuals are more likely to engage in pro-environmental behaviour when their values(especially biosphere and altruistic),beliefs(about environmental consequences),and norms(personal responsibility to act)align.The findings of this study underscore the critical role of climate change awareness in fostering environmental and earth stewardship.The paper recommends that Governments of the country(State and federal)should take urgent steps in sensitising the general public on the causes and impact of climate change. 展开更多
关键词 Climate Change EARTH environment Value-Belief-Norm STEWARDSHIP
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Radon emissions as indicators of changes in tropical Andean ecosystems emerging after glacial retreat under climate forcing
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作者 Christian YARLEQUE Lucia MORENO +2 位作者 Jorge MARTÍNEZ Victor POMA Susan COAGUILA 《Journal of Mountain Science》 2026年第3期905-919,共15页
This study examines radon emissions as potential proxies for environmental change in tropical Andean ecosystems undergoing rapid glacier retreat due to climate forcing.The research was conducted in the proglacial zone... This study examines radon emissions as potential proxies for environmental change in tropical Andean ecosystems undergoing rapid glacier retreat due to climate forcing.The research was conducted in the proglacial zone of the Yana Ucsha glacier in the Peruvian Andes,where field campaigns between July and November 2023 yielded radon measurements at approximately 28-day intervals across ten monitoring sites(M1-M10).Radon flux was measured using LR115 detectors and complemented by analyses of soil texture and the topographic wetness index(TWI)to assess the influence of environmental variables.Results demonstrate that radon emissions are strongly modulated by soil moisture,which in turn is regulated by regional air temperature and glacier runoff.A significant inverse relationship was identified between radon exhalation and regional air temperature,indicating that warmer periods suppress radon release due to increased soil moisture from enhanced glacier melt.Conversely,the coldest monitoring interval(second period)exhibited markedly higher radon exhalation,reaching up to 0.45 and 0.32 Bq m^(-2)hm^(-1)at sites M1 and M4,respectively-approximately four to five times greater than the baseline range(0-0.10 Bq m^(-2)hm^(-1))observed during other periods.This pronounced temporal anomaly coincided with lower regional air temperatures,reduced glacier runoff,and drier soil conditions,highlighting strong climatic control on radon emissions.These findings suggest that ongoing glacier retreat and climate change may constrain or reduce radon emission rates in Andean proglacial environments,with important implications for environmental monitoring and ecosystem dynamics.Overall,this study provides novel insights into the interactions among cryospheric,atmospheric,and radon dynamics in the tropical Andes. 展开更多
关键词 RADON Proglacial environment ANDES Glaciers Climatic forcings Temperature
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Preliminary Study on the Theory of Environmentally Adaptive Changes in Flue-Cured Tobacco during Growth
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作者 Liuping DENG Ajuan ZHAO +13 位作者 Guoqiang HUANG Liangjiao Jiongling ZHAO Li LI Shaoxiang ZHANG Shimin ZHOU Jianyong LI Qiongfeng LIU Huan FAN Dewu ZENG Xinchao LI Liangrui PENG Sicheng CAI Dongcheng LI 《Asian Agricultural Research》 2026年第2期30-34,共5页
Starting from the foundational static traits underlying the growth and development of flue-cured tobacco, this research conducts a systematic examination of the phenomena and theoretical principles associated with env... Starting from the foundational static traits underlying the growth and development of flue-cured tobacco, this research conducts a systematic examination of the phenomena and theoretical principles associated with environment-driven adaptive changes during its cultivation. It was found that environmental variables-including temperature, light, and moisture-elicit directional shifts in static traits ( e.g. , chemical composition, morphological architecture, and leaf tissue structure) toward enhanced environmental adaptation, characterized by graduality, juvenility, similarity, and correlativity. Upon alterations in ambient conditions, flue-cured tobacco modulates its static traits through integrated physical, chemical, and biological-genetic mechanisms, aiming to optimize resource utilization, mitigate environmental constraints, and preserve internal homeostasis alongside metabolic balance. The investigation further reveals that the adaptive scope of flue-cured tobacco to field environments is malleable and can be extended and elevated via adaptive conditioning commencing at the juvenile stage. In addition, the adaptive alignment between static traits and environmental parameters exerts a substantial impact on the plant s growth dynamics, yield performance, and quality attributes. Beyond its relevance to flue-cured tobacco, the proposed theory offers a meaningful framework for elucidating the pervasive adaptive strategies employed by plants and broader biological systems in response to environmental contingencies. 展开更多
关键词 Flue-cured tobacco Static trait environment Adaptive change
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Evaluation of Global NWP Data on the Convection Environment over the Data-Sparse Northern South China Sea by Long-Term Observations
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作者 Ling HUANG Zhiyong MENG Murong ZHANG 《Advances in Atmospheric Sciences》 2026年第5期965-980,共16页
The coastal regions of southern China experience the country's most frequent convective weather.Accurately representing the low-level upstream atmospheric state over the data-sparse South China Sea(SCS)is crucial ... The coastal regions of southern China experience the country's most frequent convective weather.Accurately representing the low-level upstream atmospheric state over the data-sparse South China Sea(SCS)is crucial for reliable convection predictions in numerical models.Utilizing 10 years of radiosonde observations launched over the SCS,this study presents the upstream offshore convective environments and evaluates the global model data performance including NCEP FNL,ERA5,CRA-40,JRA-3Q,and MERRA-2.Results show that thermodynamic state variables such as temperature and humidity exhibit greater biases than kinetic variables,particularly at low levels.Deeper-layer parameters exhibit smaller uncertainties,especially wind-related variables,while moisture-related parameters have the largest uncertainties,compared to shallower-layer parameters.All model data tend to underestimate the conditional instability and equilibrium level,while overestimating the condensation level,storm relative helicity(SRH),with minimal bias in lapse rate,convective inhibition,vertical wind shear(VWS),and mean winds.These biases primarily arise from the model data's underestimation of temperature and moisture below 700 hPa and lower wind speeds below 950 hPa.Among the global models,CRA-40 performs best in dynamic parameters,with highest correlation and lowest mean absolute error in low-level winds,SRH,VWS,and mean winds.ERA5 excels in thermodynamic parameters.Additional convective-permitting numerical experiments indicate that minor initial condition errors over the upstream ocean significantly affect coastal rainfall production.The rainfall production on windward coasts is most sensitive to the low-level air temperature errors during nocturnal hours,while the rainfall over the PRD is most sensitive to the low-level wind errors. 展开更多
关键词 RADIOSONDE convective environments RAINFALL northern South China Sea
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The Impact of the Digital Economy on Regional Innovation Performance:A Business Environment Perspective
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作者 Wang Linmei Zhou Menglin 《Contemporary Social Sciences》 2026年第1期52-70,共19页
In the context of the revolution in new technologies,a key question is whether the rapid growth of the digital economy,driven by digital technologies,has improved regional innovation performance.Using inter-provincial... In the context of the revolution in new technologies,a key question is whether the rapid growth of the digital economy,driven by digital technologies,has improved regional innovation performance.Using inter-provincial panel data from China(2012–2022)and adopting a business environment perspective,this study applies a Panel Extended Regression Model(PERM),a Panel Simultaneous Equation Model(PSEM),and a Tobit-IV model to analyze how the development of the digital economy influences regional innovation.The results reveal a pronounced U-shaped relationship between the digital economy and the regional innovation performance at the provincial level in China,with the business environment serving as a significant mediator in this relationship.Moreover,regional innovation performance in China exhibits a“ratchet effect,”with the impact of the digital economy varying markedly across regions.While the eastern and western regions have entered an upward phase,whereby the digital economy boosts innovation,the central region displays a weaker effect.Further analysis indicates that the synergy between the business environment and the digital economy in driving innovation remains suboptimal.These findings were supported by robust checks.This study offers theoretical insights and empirical evidence that support the coordinated development of digital government and the digital factor market,as well as business environment reforms that are in alignment with the innovation demands of the digital era. 展开更多
关键词 digital economy regional innovation performance business environment
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Temperature-Dependent Infrared Engineering for Extreme Environments:All-Dielectric Thermal Photonic Metamaterials Stable at 1873 K in Air
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作者 Yang Liu He Lin +5 位作者 Yunxia Zhou Liming Yuan Yanqin Wang Xiaoliang Ma Cheng Huang Xiangang Luo 《Nano-Micro Letters》 2026年第6期879-897,共19页
The development of infrared engineering technologies for extreme environments remains a formidable challenge due to the inherent trade-offs among optical performance,thermal stability,and mechanical integrity in therm... The development of infrared engineering technologies for extreme environments remains a formidable challenge due to the inherent trade-offs among optical performance,thermal stability,and mechanical integrity in thermal photonic metamaterials(TPMs).This work introduces a novel multi-obj ective design framework and demonstrates the design,fabrication,and validation of a TPM operating under extreme temperatures up to 1873 K.We have established a holistic design framework integrating temperaturedependent neural network and Pareto multi-obj ective optimization to co-optimize spectral response,component light-weighting,and structural efficiency.The framework achieves 100 times faster computation than genetic algorithms.The performance of the designed TPM was evaluated under various atmospheric models and detection distances.The TPM achieved a peak radiance suppression efficiency of 82%and a maximum attenuation of-7.4 dB at 1200-1500 K.Experimentally,we fabricated an all-dielectric TPM using a refractory TiO_(2)/BeO multilayer stack with only 5 layers and 2um total thickness.The optimized structure shows high reflectivity(0.62 at 3-5 um;0.48 at 8-14μm)for radiative suppression and high emissivity(0.87 at 5-8μm)for radiative cooling.The TPM withstands 1873 K for 12 h in air with less than 3%spectral drift,retaining excellent mechanical properties.On high-temperature components,it achieves 40-50%radiative suppression and 40-60 K(~10.1 kW m^(-2))radiative cooling at 1100 K,endures over 20 times thermal shock cycles(>150 K s^(-1),700-1500 K),and maintains stable performance over 5 cycles,with 78%visible and 98%microwave transmittance.This work establishes a new paradigm in the design and application of photonic materials for extreme environments. 展开更多
关键词 Extreme environment Thermal photonic METAMATERIAL Machine learning Thermal management
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DL-YOLO:AMulti-Scale Feature Fusion Detection Algorithm for Low-Light Environments
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作者 Yuanmeng Chang Hongmei Liu 《Computers, Materials & Continua》 2026年第5期1901-1915,共15页
Driven by rapid advances in deep learning,object detection has been widely adopted across diverse application scenarios.However,in low-light conditions,critical visual cues of target objects are severely degraded,posi... Driven by rapid advances in deep learning,object detection has been widely adopted across diverse application scenarios.However,in low-light conditions,critical visual cues of target objects are severely degraded,posing a significant challenge for accurate low-light object detection.Existing methods struggle to preserve discriminative features while maintaining semantic consistency between low-light and normal-light images.For this purpose,this study proposes a DL-YOLO model specially tailored for low-light detection.To mitigate target feature attenuation introduced by repeated downsampling,we design aMulti-Scale FeatureConvolution(MSF-Conv)module that captures rich,multi-level details via multi-scale feature learning,thereby reducing model complexity and computational cost.For feature fusion,we integrated the C3k2-DWRmodule by embedding the Dilation-wise Residual(DWR)mechanism into the 2-core optimized Cross Stage Partial(C3)framework,achieving efficient feature integration.In addition,we replace conventional localization losses with WIoU(Weighted Intersection over Union),which dynamically adjusts gradient gain according to sample quality,thereby improving localization robustness and precision.Experiments on the ExDark dataset demonstrate that DL-YOLO delivers strong low-light detection performance.The relevant code is published at https://github.com/cym0997/DL-YOLO. 展开更多
关键词 Multi-scale feature extraction object detection low-light environments ExDark dataset
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VIF-YOLO:A Visible-Infrared Fusion YOLO Model for Real-Time Human Detection in Dense Smoke Environments
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作者 Wenhe Chen Yue Wang +4 位作者 Shuonan Shen LeerHua Caixia Zheng Qi Pu Xundiao Ma 《Computers, Materials & Continua》 2026年第4期1463-1484,共22页
In fire rescue scenarios,traditional manual operations are highly dangerous,as dense smoke,low visibility,extreme heat,and toxic gases not only hinder rescue efficiency but also endanger firefighters’safety.Although ... In fire rescue scenarios,traditional manual operations are highly dangerous,as dense smoke,low visibility,extreme heat,and toxic gases not only hinder rescue efficiency but also endanger firefighters’safety.Although intelligent rescue robots can enter hazardous environments in place of humans,smoke poses major challenges for human detection algorithms.These challenges include the attenuation of visible and infrared signals,complex thermal fields,and interference frombackground objects,all ofwhichmake it difficult to accurately identify trapped individuals.To address this problem,we propose VIF-YOLO,a visible–infrared fusion model for real-time human detection in dense smoke environments.The framework introduces a lightweight multimodal fusion(LMF)module based on learnable low-rank representation blocks to end-to-end integrate visible and infrared images,preserving fine details while enhancing salient features.In addition,an efficient multiscale attention(EMA)mechanism is incorporated into the YOLOv10n backbone to improve feature representation under low-light conditions.Extensive experiments on our newly constructedmultimodal smoke human detection(MSHD)dataset demonstrate thatVIF-YOLOachievesmAP50 of 99.5%,precision of 99.2%,and recall of 99.3%,outperforming YOLOv10n by a clear margin.Furthermore,when deployed on the NVIDIA Jetson Xavier NX,VIF-YOLO attains 40.6 FPS with an average inference latency of 24.6 ms,validating its real-time capability on edge-computing platforms.These results confirm that VIF-YOLO provides accurate,robust,and fast detection across complex backgrounds and diverse smoke conditions,ensuring reliable and rapid localization of individuals in need of rescue. 展开更多
关键词 Fire rescue dense smoke environments human detection multimodal fusion YOLO
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A conceptual analysis of reflective supervision for creating a positive intensive care practice environment
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作者 Mpho Grace Chipu 《International Journal of Nursing Sciences》 2026年第1期88-95,共8页
Objectives This study aimed to explore and clarify the concept of reflective supervision as a professional self-care strategy to create a positive Intensive Care Unit(ICU)practice environment.Methods Walker and Avant... Objectives This study aimed to explore and clarify the concept of reflective supervision as a professional self-care strategy to create a positive Intensive Care Unit(ICU)practice environment.Methods Walker and Avant’s eight-step concept analysis approach was utilized to identify and define the attributes,antecedents,and consequences of reflective supervision in the ICU.An extensive literature search was conducted across various databases,including Google Scholar,CINAHL,PubMed.Articles published from 2005 to 2025 were identified.We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)2020 statement to indicate the included articles and extract related data based on relevance.Results Forty articles were included in the analysis.The identified attributes included the supervisor-supervisee relationship,effective communication,teamwork,collaborations,reflection,competencies,feedback,continuous support,and autonomous choice.The identified antecedents included participation,supportive supervision,flexibility,open-door policy,training,and motivation.Consequences impacting the success of reflective supervision were identified as promotion of resiliency,autonomy,work-life balance,self-awareness,increased self-esteem,professional development,critical thinking,increased job satisfaction,and enhanced commitment.Conclusions Reflective supervision is a complex professional self-care strategy that enhances ICU practice,by promoting nurses’well-being,self-awareness,therapeutic skills,and professional development. 展开更多
关键词 Concept analysis Intensive Care Unit NURSING Positive environment Reflective supervision
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