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Research on the Characteristics of Hydrothermal Alteration Minerals in the Qiucun Gold Deposit,SE China:Based on Hyperspectral Remote Sensing Technology
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作者 Hongliang Zhang Liancun Xiu +4 位作者 Yan Zhou Kai Yang Bin Yang Yan Lu Liang Yin 《Journal of Environmental & Earth Sciences》 2026年第2期361-378,共18页
This review summarizes studies of hydrothermal alteration minerals at the Qiucun gold deposit in southeastern China and focuses on characterization and mapping of the deposit using hyperspectral remote sensing.The dep... This review summarizes studies of hydrothermal alteration minerals at the Qiucun gold deposit in southeastern China and focuses on characterization and mapping of the deposit using hyperspectral remote sensing.The deposit exhibits multistage fluid-rock interaction,as evidenced by systematic alteration assemblages,including silicification,sericitization by white micas,the development of argillaceous clays,variable chloritization,and locally significant carbonate alteration.We describe the genetic importance of such mineral groups and emphasize their diagnostic Visible and Near-Infrared to Short-Wave Infrared(VNIR-SWIR)spectral signatures,especially Al-OH,Mg-OH/Fe-OH,and CO3 absorption bands,which make it possible to distinguish between minerals,not to mention the fact that,in some instances,compositional trends may be predicted.This review’s methodological advances are discussed beginning with data collection at satellite,airborne,and ground levels,proceeding to processing procedures,such as atmospheric and topographic correction,and culminating in spectral analysis,including continuum removal,spectral matching,and unmixing/classification techniques.An integrated study of hyperspectral findings reveals that alteration minerals develop spatially coherent zones that are strongly controlled by fault/fracture structures and host-rock reactivity,producing proximal silicification/sericitization cores and larger silicified/larcenies of argillaceous rocks owing to diverse apex coverings of carbonate.This should be combined with petrography and geochemistry to address overprinting,mixed pixels,and surface weathering,and to couple mineral maps with ore-forming processes.The review finds that hyperspectral remote sensing offers a solid modeling platform for the deposit-scale alteration at Qiucun and other hydrothermal gold systems,and outlines the directions for future research to integrate quantitatively and more threedimensional alteration characterization. 展开更多
关键词 HYPERSPECTRAL remote sensing HYDROTHERMAL ALTERATION Qiucun gold deposit ALTERATION mineral mapping VNIR-SWIR spectroscopy
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Remote Sensing Big Data for Sustainable Development:Emerging Analytics,Applications,and Global Pathways
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作者 Huiling Li 《Journal of Environmental & Earth Sciences》 2026年第1期117-145,共29页
The development of remote sensing has seen the creation of a global measurement infrastructure of sustainable development due to growing multipolar archives,rising revisit frequency,and the availability of cloud-acces... The development of remote sensing has seen the creation of a global measurement infrastructure of sustainable development due to growing multipolar archives,rising revisit frequency,and the availability of cloud-accessible platforms of Earth observation.This review summarizes how remote sensing big data is being organized into decision-grade sustainability intelligence,the new approaches to analytics,and how Sustainable Development Goals(SDGs)-oriented application pathways inter-relate action pathways that bridge observations with action.The terminologies like new data ecosystem,data readiness and interoperability,changing economics of scalable computation,and detailing the functions of diversity of modalities(optical,Synthetic Aperture Radar—SAR,thermal,Light Detection and Ranging—LiDAR,hyperspectral)have been defined.These themes of analytics,which are transforming the practice of operational analytics,are then condensed:foundations and self-supervised learning of transferable representations,multi-modal fusion to gap fill and richer inference,spatiotemporal intelligence to trend of early warning,physics-aware hybrid methods to enhance robustness and meaning under non-stationary conditions.Across the climate risk,food systems,water resources,sustainable cities,ecosystems and biodiversity,energy transitions,and health exposure pathways,the roles of Earth Observation(EO)products as direct measures and proxies,and concepts of validating,semantic comparability,and communicating uncertainties play a key role in EO products becoming credible when faced with high-stakes deployment decisions.Lastly,we chart world ways of implementation via monitoring services,early warning systems,and systems of multiple regimes,and previously underline cross-cutting priorities,scalable structures in validation,performance,so that domains of shift,agreeable governance,and Dual-use risk safeguards,and sustainable lifecycle support of EO services.These priorities form a realistic set of priorities on the alignment of remote sensing innovation with quantifiable SDGs progress. 展开更多
关键词 Remote sensing Big Data Sustainable Development Goals Geospatial Artificial Intelligence(AI) Measurement Reporting and Verification(MRV) Uncertainty Quantification
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基于CS-BP-PID算法的烟叶密集烤房温度控制系统
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作者 沈少君 闫九福 +4 位作者 卢雨 林晓路 杜超凡 朱荣光 孟令峰 《农机化研究》 北大核心 2026年第4期95-102,共8页
烟叶烘烤作为决定烟叶品质的核心环节,其温湿度控制的精准性至关重要。针对当前密集烤房多阶段温度控制精度差、波动范围大、响应时间长等直接影响烟叶色泽、香气、化学成分、经济价值等问题,设计了一种基于布谷鸟算法(CS)优化的BP神经... 烟叶烘烤作为决定烟叶品质的核心环节,其温湿度控制的精准性至关重要。针对当前密集烤房多阶段温度控制精度差、波动范围大、响应时间长等直接影响烟叶色泽、香气、化学成分、经济价值等问题,设计了一种基于布谷鸟算法(CS)优化的BP神经网络PID控制器。通过模拟布谷鸟的寄生行为和莱维飞行特性,对BP神经网络的初始权重进行优化,加快了BP神经网络的自学习速度,以实现密集烤房温度的快速精准调控,降低了超调量,提高了响应速度。同时,基于树莓派4B搭建了密集烤房温湿度控制试验平台,并对控制器性能进行了验证。结果表明:CS-BP-PID控制器上升时间为79.35 s,峰值时间为180.00 s,调节时间为249.38 s,最大超调量为3.25%,相比常规PID控制器缩短了38.18%,调节时间缩短了47.05%,峰值时间和最大超调量减少了50%以上,满足系统温度控制需求。通过多阶段烟叶烘烤试验,上等烟比例提高了14.45%,经济效益得到了显著提升。该控制器综合性能优良,达到了精准控温控湿的效果。 展开更多
关键词 烟叶密集烤房 温度控制系统 cs-BP-PID算法
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计算机科学2.0(CS2.0)初探
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作者 李国杰 《计算》 2026年第1期5-5,共1页
经典的计算机科学(CS1.0)建立在一组长期未被系统反思的前提之上:1)计算是抽象符号操作;2)计算过程可被算法描述;3)物理实现是不影响计算本质的“载体”。然而,当代计算实践正在系统性地脱离这些基本假设,“算法+程序执行”已不再是对... 经典的计算机科学(CS1.0)建立在一组长期未被系统反思的前提之上:1)计算是抽象符号操作;2)计算过程可被算法描述;3)物理实现是不影响计算本质的“载体”。然而,当代计算实践正在系统性地脱离这些基本假设,“算法+程序执行”已不再是对计算的充分描述。AI大模型的内部表示是高维连续流形结构,没有稳定、可命名的语义对象,你无法说模型正在处理哪个符号、哪条信息,只能说它的状态正在向某个吸引子演化,这已经不是经典意义上的“信息处理”。如果计算机科学不能驾驭这种非离散、非符号、非算法的动力系统,在人工智能的浪潮中将逐渐被边缘化。 展开更多
关键词 经典计算机科学 cs2.0 cs1.0
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中国湖沼沉积物中^(137)Cs时空变化特征及其对人类世的指示意义
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作者 邢伟 焦阳 +3 位作者 李想 张艺钊 李霄 鲍锟山 《地理科学》 北大核心 2026年第3期581-594,共14页
本研究收集整理了中国79个湖泊和沼泽沉积钻孔中^(137)Cs数据,探讨了其时空分布特征及其对人类世时限的指示意义。研究发现:(1)中国湖沼钻孔中^(137)Cs沉积记录普遍可以检测到1963年蓄积峰,该蓄积峰作为主计年时标层位清晰、易识别,具... 本研究收集整理了中国79个湖泊和沼泽沉积钻孔中^(137)Cs数据,探讨了其时空分布特征及其对人类世时限的指示意义。研究发现:(1)中国湖沼钻孔中^(137)Cs沉积记录普遍可以检测到1963年蓄积峰,该蓄积峰作为主计年时标层位清晰、易识别,具有明确的时标特征;沉积钻孔中1986年^(137)Cs蓄积峰可作为次级计年时标,但需要结合其它测年指标确认其可靠性;(2)中国湖沼钻孔中^(137)Cs记录存在显著的时空差异,受地形地貌、降水、径流侵蚀及人类活动等因素的影响,^(137)Cs比活度整体上由北向南递减,且在1960—1980年^(137)Cs比活度值达到最高水平;(3)中国1963年^(137)Cs主蓄积峰时标明确,是可靠的年代层标志,可作为潜在地层证据指示人类活动对区域环境的影响。 展开更多
关键词 ^(137)cs 时标 湖沼沉积 人类世 中国
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退火温度对三辊斜轧45CS/TA2复合管微观组织和力学性能的影响
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作者 任晏辰 牛辉 +3 位作者 付伦 季策 王涛 黄庆学 《塑性工程学报》 北大核心 2026年第1期245-255,共11页
针对三辊斜轧后的45CS/TA2复合管存在残余应力大、伸长率低的问题,研究了退火温度对其微观组织和力学性能的影响,目的是在保持良好抗拉强度和剪切强度的同时提升伸长率。结果表明,经550℃退火的45CS/TA2复合管综合性能最好:抗拉强度达到... 针对三辊斜轧后的45CS/TA2复合管存在残余应力大、伸长率低的问题,研究了退火温度对其微观组织和力学性能的影响,目的是在保持良好抗拉强度和剪切强度的同时提升伸长率。结果表明,经550℃退火的45CS/TA2复合管综合性能最好:抗拉强度达到595 MPa,剪切强度为275 MPa,伸长率为41%。微观分析表明,550℃退火后,界面形成了厚度适宜的TiC层,抵消了动态回复带来的不利影响,提升了界面结合强度。同时,钛侧轧制变形晶粒因退火转变为亚结构而使基体伸长率提升,基于强结合的异质金属在拉伸过程中持续协同变形效应,促使整体伸长率提升。而经650℃退火的复合管,由于TiC层过厚,导致界面结合强度下降,虽然钛侧发生了再结晶,但由于界面结合强度大幅下降,分层失效显著,导致伸长率提升并不明显。 展开更多
关键词 45cs/TA2复合管 三辊斜轧 界面微观结构 力学性能
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Fabrication and Mechano-sensing Characteristics of Bending Polypyrrole Actuator
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作者 CHEN Jinyou HU Wei 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2025年第1期240-245,共6页
To prepare a conductive polymer actuator with decent performance,a self-built experimental platform for the preparation of polypyrrole film is employed.One of the essential goals is to examine the mechanical character... To prepare a conductive polymer actuator with decent performance,a self-built experimental platform for the preparation of polypyrrole film is employed.One of the essential goals is to examine the mechanical characteristics of the actuator in the presence of various combinations of process parameters,combined with the orthogonal test method of"four factors and three levels".The bending and sensing characteristics of actuators of various sizes are methodically examined using a self-made bending polypyrrole actuator.The functional relationship between the bending displacement and the output voltage signal is established by studying the characteristics of the actuator sensor subjected to various degrees of bending.The experimental results reveal that the bending displacement of the actuator tip almost exhibits a linear variation as a function of length and width.When the voltage reaches 0.8 V,the bending speed of the actuator tends to be stable.Finally,the mechanical properties of the self-assembled polypyrrole actuator are verified by the design and fabrication of the microgripper. 展开更多
关键词 conductive polymer POLYPYRROLE mechanical characteristics actuators sensing characteristics
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社会资本何以赋能铸牢中华民族共同体意识?——基于CSS2021问卷数据的QCA定性比较分析
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作者 林艺 张梓涵 《中共云南省委党校学报》 2026年第1期150-164,172,共16页
构建和培育社会资本是铸牢中华民族共同体意识不可或缺的一环。基于CSS2021的4 280份问卷调查数据,采用fs QCA的研究方法对影响铸牢中华民族共同体意识的社会资本要素及其组态路径进行实证探索。研究发现:铸牢中华民族共同体意识受多种... 构建和培育社会资本是铸牢中华民族共同体意识不可或缺的一环。基于CSS2021的4 280份问卷调查数据,采用fs QCA的研究方法对影响铸牢中华民族共同体意识的社会资本要素及其组态路径进行实证探索。研究发现:铸牢中华民族共同体意识受多种社会资本要素的共同影响,单一要素不能成为其必要条件,但公共事务参与要素的缺失必然导致低水平的铸牢中华民族共同体意识。存在三条组态路径能推动铸牢中华民族共同体意识,分别是“社会心理构建型”路径、“信任—规范协同驱动型”路径、“公共精神培育型”路径,不同路径的影响机制有所不同。三条组态共同指向政府信任要素为铸牢中华民族共同体意识的核心要素。对此,应推动各族群众积极参与社会公共事务、推进民族事务治理法治化,既要维护法律规范权威也要重视合理的道德规范效用,须不断强化公民身份认同,培育公共精神。 展开更多
关键词 社会资本理论 铸牢中华民族共同体意识 因素与路径 fsQCA
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干法后处理熔盐中Sr/Cs去除方法的研究进展
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作者 刘占一 李勉 +2 位作者 欧阳晓平 柴之芳 黄庆 《无机材料学报》 北大核心 2026年第2期150-158,共9页
干法后处理技术具有耐辐照、防扩散和简化废物处理等特点,是未来先进快堆乏燃料后处理的优选技术。其中,熔盐电解精炼是干法后处理的核心技术,主要利用铀、钚等锕系元素与其他裂变元素在熔盐体系中的氧化还原电位差来实现锕系元素的分... 干法后处理技术具有耐辐照、防扩散和简化废物处理等特点,是未来先进快堆乏燃料后处理的优选技术。其中,熔盐电解精炼是干法后处理的核心技术,主要利用铀、钚等锕系元素与其他裂变元素在熔盐体系中的氧化还原电位差来实现锕系元素的分离回收。然而,在电解精炼过程中,镧系元素和Sr/Cs等裂变元素在熔盐中不断积累,改变了熔盐的理化性质,严重影响电解精炼效率。另外,^(90)Sr和^(137)Cs等裂变产物属于水溶性长寿命核素,若处理不当,将对环境造成巨大危害。因此,有效净化熔盐中的Sr/Cs等裂变元素不仅是提高熔盐电解干法后处理效率的迫切需求,也是减少放射性废物排放的重要手段。本文总结了熔盐中的Sr/Cs去除方法的研究现状,对比分析了电解法、结晶法、减压蒸馏法、沉淀法和离子交换法等不同方法的分离原理和分离效果,并探讨了未来的发展方向及潜在的可用材料体系。 展开更多
关键词 干法后处理 电解精炼 SR cs 熔盐净化 综述
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V_(2)O_(5)/TiO_(2)和Cs/Co_(3)O_(4)催化剂联合催化脱除NO_(x)和N_(2)O
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作者 苗静文 樊星 +1 位作者 刘若雯 张雅坤 《环境工程》 2026年第2期103-111,共9页
针对高效脱除硝酸生产尾气中NO_(x)和N_(2)O的需求,提出了先催化NO_(x)还原后催化N_(2)O分解的技术路线。分别考察了V_(2)O_(5)/TiO_(2)和Co_(3)O_(4)基催化剂催化NO_(x)还原和N_(2)O分解的性能,在优选出2.0Cs/Co_(3)O_(4)催化剂的基础... 针对高效脱除硝酸生产尾气中NO_(x)和N_(2)O的需求,提出了先催化NO_(x)还原后催化N_(2)O分解的技术路线。分别考察了V_(2)O_(5)/TiO_(2)和Co_(3)O_(4)基催化剂催化NO_(x)还原和N_(2)O分解的性能,在优选出2.0Cs/Co_(3)O_(4)催化剂的基础上,重点考察了在V_(2)O_(5)/TiO_(2)催化剂之后串接2.0Cs/Co_(3)O_(4)催化剂的联合催化脱除NO_(x)和N_(2)O的性能,并采用N_(2)吸脱附、XRD、XPS和O_(2)-TPD等手段对催化剂理化特性进行表征。结果表明:V_(2)O_(5)/TiO_(2)催化还原NO_(x)时,进气中含2%H_(2)O有利于拓宽活性温度窗口和提高N_(2)选择性,以及抑制N_(2)O形成。在Co_(3)O_(4)表面负载2.0%Cs显著提高了催化剂催化N_(2)O分解性能,这可能与Cs的引入导致部分Co^(3+)还原为Co^(2+)以及催化剂表面形成了更多氧空位有关。高温(400℃)下通入2%H_(2)O对2.0Cs/Co_(3)O_(4)催化N_(2)O分解的抑制作用较弱,但同时通入2%H_(2)O和50×10^(-6) NO显著抑制了2.0Cs/Co_(3)O_(4)催化剂的活性。采用先V_(2)O_(5)/TiO_(2)后2.0Cs/Co_(3)O_(4)的两段式催化剂联合脱除NO_(x)和N_(2)O时,前端的V_(2)O_(5)/TiO_(2)催化剂主要催化NO_(x)的还原反应,N_(2)O对脱硝过程的影响有限;在V_(2)O_(5)/TiO_(2)催化剂高效脱除NO_(x)(和NH_(3))的温度范围内,后端的2.0Cs/Co_(3)O_(4)催化剂可较为稳定地催化N_(2)O分解;在温度400℃,进气中含2%H_(2)O时,NO_(x)和NH_(3)转化率均接近100%,N_(2)O转化率为61.3%。 展开更多
关键词 NO_(x)还原 N_(2)O分解 V_(2)O_(5)/TiO_(2) cs/Co_(3)O_(4) 联合催化
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CMT-CS工艺对4043铝合金增材制造成形质量的影响
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作者 刘康哲 杨永强 +2 位作者 宋长辉 李阳 张世钦 《航空制造技术》 北大核心 2026年第7期145-156,共12页
以ER4043铝合金焊丝为成形材料,研究了冷金属过渡–循环步进(CMT-CS)电弧增材工艺对铝合金薄壁件成形质量的影响。采用单因素试验方法研究了焊接电流、焊接速度、间隔时间和间隔周期数对薄壁件宏观尺寸、表面质量、气孔及微观组织的影... 以ER4043铝合金焊丝为成形材料,研究了冷金属过渡–循环步进(CMT-CS)电弧增材工艺对铝合金薄壁件成形质量的影响。采用单因素试验方法研究了焊接电流、焊接速度、间隔时间和间隔周期数对薄壁件宏观尺寸、表面质量、气孔及微观组织的影响。结果表明,相较于CMT一般工艺,CMT-CS工艺能够进一步精确控制沉积过程,并降低热输入。不同工艺参数下的热输入和材料量不同,产生了不同尺寸的熔池,进而对电弧增材薄壁件的宏观尺寸和表面质量产生影响。CMT-CS工艺具有比CMT一般工艺更为优秀的气孔抑制能力。横向试样抗拉强度达到(146.59±3.52)MPa,延伸率达到(22.29±3.13)%,较铸造件有明显提高。研究表明,通过合理优化CMT-CS工艺参数可以有效控制薄壁件的形貌和微观组织,为CMT-CS工艺的应用和4043铝合金的电弧增材制造提供了参考依据。 展开更多
关键词 电弧增材制造(WAAM) 冷金属过渡–循环步进(CMT-cs) 4043铝合金 组织性能 热输入
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福建海域海产品中^(90)Sr和^(137)Cs的放射性水平及剂量评估
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作者 柯思因 钟强强 +6 位作者 张福乐 李聪 宾丽 陈越 吴镇 黄德坤 于涛 《海洋环境科学》 北大核心 2026年第1期25-33,共9页
2023年8月日本福岛核污染水排海引发公众对海产品安全的担忧。本研究通过分析2024年福建海域海产品中人工放射性核素^(90)Sr和^(137)Cs的比活度,系统评估我国近海海产品放射性本底水平。全样分析的结果表明,海产品中^(90)Sr和^(137)Cs... 2023年8月日本福岛核污染水排海引发公众对海产品安全的担忧。本研究通过分析2024年福建海域海产品中人工放射性核素^(90)Sr和^(137)Cs的比活度,系统评估我国近海海产品放射性本底水平。全样分析的结果表明,海产品中^(90)Sr和^(137)Cs的比活度范围分别为<0.004~0.155 Bq/kg和0.006~0.132 Bq/kg(鲜重);将海产品分为可食部分和不可食部分并进一步分析发现,^(137)Cs更易富集于肌肉组织等可食部分,而^(90)Sr倾向富集在骨骼等不可食部分。总体而言,福建海域海产品中^(137)Cs比活度水平与我国山东等邻近海域相当,远低于福岛附近海域。本文评估了居民因食用海产品而摄入^(90)Sr和^(137)Cs所致的年待积有效剂量分别为0.0051μSv/a和0.0062μSv/a,约为全球自然本底辐射(2.4 mSv/a)的0.25‰。本研究为评估核污染水排放对福建海域的后续影响提供了基础数据支撑。 展开更多
关键词 福岛核污染水 ^(90)Sr ^(137)cs 海产品 剂量评估
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海水中^(134)Cs效率曲线修正法和绝对活度测量法研究
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作者 朱毅 张磊 金峰 《核技术》 北大核心 2026年第3期66-73,共8页
近几年海洋放射性核素的监测面临诸多挑战,如监测数据的准确性和可靠性、监测方法的成本和效率等方面。本文重点对提高海水中^(134)Cs核素的分析效率和结果准确性等方面开展研究。采用了新的磷钼酸铵(Ammonium Molybdophosphate,AMP)吸... 近几年海洋放射性核素的监测面临诸多挑战,如监测数据的准确性和可靠性、监测方法的成本和效率等方面。本文重点对提高海水中^(134)Cs核素的分析效率和结果准确性等方面开展研究。采用了新的磷钼酸铵(Ammonium Molybdophosphate,AMP)吸附试剂的合成方法,新合成的试剂提高了海水中铯同位素的富集效率。通过三种方法分析了海水中^(134)Cs核素活度,第一种方法是传统效率曲线法,该方法需对^(134)Cs核素进行级联符合相加修正,本文采用TrueCoinc程序,该程序结合全能峰效率,总峰比曲线等参数,计算了^(134)Cs核素的7个能量峰的符合相加修正因子,计算结果与真值符合得较好;第二种方法是简化的符合峰绝对活度计算法,该方法无需实验室标准物质刻度探测器,仅依赖全能峰计数率,符合峰计数率和总净计数率等参数,对^(134)Cs核素选用了发射概率较高的604 keV和795 keV两个能峰,对^(134)Cs绝对活度计算公式进行了一定的近似和简化,但验证结果和参考活度的偏差均在6%以内;第三种方法是符合峰距离拟合法,是对符合峰绝对活度的一种优化方法,该方法仅需全能峰净计数率和符合峰净计数率,无需全谱总净计数率参数,使绝对活度计算方法适用于有干扰核素的样品,拓展了该方法的应用范围。 展开更多
关键词 效率曲线 符合峰 磷钼酸铵 高纯锗谱仪 ^(134)cs核素
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Innovative Application of Emerging Sensing Technologies in Mechatronics Systems
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作者 Jianming Feng 《Journal of Electronic Research and Application》 2025年第4期229-234,共6页
With the rapid development of science and technology,new sensing technology has been used increasingly in mechatronics system,for the system of intelligent,automation and efficiency,provide strong support.Emerging sen... With the rapid development of science and technology,new sensing technology has been used increasingly in mechatronics system,for the system of intelligent,automation and efficiency,provide strong support.Emerging sensor technology in electromechanical integration system of innovative applications not only promote the system of intelligent upgrade,also for its wide application in the field of multiple provides a strong support,and along with the advance of technology and application scenario development,emerging sensor technology in electromechanical integration system to play a more important role.In this regard,this paper first expounds the overview of emerging sensing technology,then analyzes the innovation and integration of emerging sensing technology and mechatronics system,and finally further explores the practical application of emerging sensing technology in mechatronics system,in order to provide some reference for relevant researchers. 展开更多
关键词 Emerging sensing technology Mechatronics system Innovative application
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光诱导CsPbCl_(3)纳米晶卤素交换UVC剂量计研究
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作者 孔令楠 陈立明 +3 位作者 阮敏毅 陈碧桑 李婉婷 李飞明 《发光学报》 北大核心 2026年第2期367-375,共9页
开发了一种基于光驱动CsPbCl_(3)钙钛矿纳米晶(PNCs)卤素交换的短波紫外线(UVC)剂量可视化传感薄膜。利用六溴环十二烷(HBCD)在254nmUVC辐照下释放Br-的特性,诱导CsPbCl_(3)PNCs发生卤素交换,形成CsPbCl_(x)Br_(3-x)结构,从而实现荧光... 开发了一种基于光驱动CsPbCl_(3)钙钛矿纳米晶(PNCs)卤素交换的短波紫外线(UVC)剂量可视化传感薄膜。利用六溴环十二烷(HBCD)在254nmUVC辐照下释放Br-的特性,诱导CsPbCl_(3)PNCs发生卤素交换,形成CsPbCl_(x)Br_(3-x)结构,从而实现荧光颜色从暗紫色向绿色的显著转变。所构建的CsPbCl_(3)/HBCD@PMMA复合剂量薄膜具有成本低、灵敏度高、响应直观等优势,在0~1.092J/cm^(2)的UVC剂量范围内实现了荧光比率型可视化监测,覆盖医院典型消毒剂量区间(0.159~1.068J/cm^(2)),可为UVC消毒设备的剂量监测提供一种简便、可靠的新方法。 展开更多
关键词 钙钛矿纳米晶 可视化传感 UVC剂量计 卤素交换
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Prominent cryogenic fluorescence temperature sensing and superior room-temperature photochromism in Bi/Eu codoped KNN transparent-ferroelectric ceramics
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作者 Ping Zhou Qifa Lin +5 位作者 Xiangfu Zeng Min Gao Chunlin Zhao Cong Lin Tengfei Lin Xiao Wu 《Journal of Rare Earths》 2025年第11期2479-2488,I0006,共11页
The growing demand for the miniaturization and multifunctionality of optoelectronic devices has promoted the development of transparent ferroelectrics.However,it is difficult for the superior multiple optical properti... The growing demand for the miniaturization and multifunctionality of optoelectronic devices has promoted the development of transparent ferroelectrics.However,it is difficult for the superior multiple optical properties of these materials to be compatible with the excellent ferroelectricity and piezoelectricity in transparent ceramics.Here,we successfully synthesized Bi/Eu codoped eco-friendly K0.5Na0.5NbO3transparent-ferroelectric ceramics with photo luminescence(PL)behavior,photochromic(PC)reactions and temperature-responsive PL.Based on the distinct optical properties of ceramics at different temperature ranges(room temperature and ultralow temperature),high utilization of multiple optical functions was realized.At room temperature,the PC behavior induced PL modulation contrast reaches 75.2%(at 592 nm),which can be applied in the optical information storage field.In the ultralow temperature range,the ceramics exhibit excellent sensitivity(with a maximum relative sensitivity of26.32%/K)via fluorescence intensity ratio technology and exhibit great application potential in noncontact optical temperature measurements.Additionally,the change in the PL intensity at different wavelengths(I_(614)/I_(592))can serve as a reliable indicator for detecting the occurrence of the phase transition from rhombohedral to orthorhombic at low temperature.This work provides a feasible paradigm for realizing the integration of ferroelectricity and multifarious optical properties in a single optoelectronic material. 展开更多
关键词 K0.5NA0.5NBO3 Rare earths Transparent-ferroelectric ceramics FIR technology Optical temperature sensing Photochromic behavior
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Spatio-Temporal Flood Inundation Dynamics and Land Use Transformation in the Jhelum River Basin Using Remote Sensing and Historical Hydrological Data
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作者 Ihsan Qadir Usama Naeem +2 位作者 Ahmed Nouman Aamir Raza Jun Wu 《Revue Internationale de Géomatique》 2025年第1期831-853,共23页
The Jhelum River Basin in Pakistan has experienced recurrent and severe flooding over the past several decades,leading to substantial economic losses,infrastructure damage,and socio-environmental disruptions.This stud... The Jhelum River Basin in Pakistan has experienced recurrent and severe flooding over the past several decades,leading to substantial economic losses,infrastructure damage,and socio-environmental disruptions.This study uses multi-temporal satellite remote sensing data with historical hydrological records to map the spatial and temporal dynamics of major flood events occurring between 1988 and 2019.By utilizing satellite imagery from Landsat 5,Landsat 8,and Sentinel-2,key flood events were analyzed through the application of water indices such as the Normalized DifferenceWater Index(NDWI)and theModified NDWI(MNDWI)to delineate flood extents.Historical discharge data from key hydrological control points,including Mangla Dam and Rasul Barrage,were incorporated to validate and interpret flood intensity and inundation patterns.Flood footprints were extracted and mapped using preand post-flood images in Google Earth Engine,while land use and land cover(LULC)analysis revealed a consistent increase in built-up areas and a corresponding decline in vegetative cover in flood-prone tehsils from 1988 to 2023.Findings indicated that the flood years 1992 and 1997were themost catastrophic,with over 180 km2 of land submerged.A substantial proportion of inundated zones consisted of agricultural land and low-lying urban settlements,underscoring the vulnerability of these areas.This study proved the effectiveness of integrating satellite imagery and historical hydrological data for spatio-temporal flood monitoring and provides essential insights for future flood risk assessment and the development of site-specific mitigation strategies in vulnerable areas of the Jhelum River Basin. 展开更多
关键词 Flood mapping land use/land cover change remote sensing NDWI MNDWI random forest classification GIS Jhelum River Basin
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Noninvasive Radar Sensing Augmented with Machine Learning for Reliable Detection of Motor Imbalance
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作者 Faten S.Alamri Adil Ali Saleem +2 位作者 Muhammad I.Khan Hafeez Ur Rehman Siddiqui Amjad Rehman 《Computer Modeling in Engineering & Sciences》 2026年第1期698-726,共29页
Motor imbalance is a critical failure mode in rotating machinery,potentially causing severe equipment damage if undetected.Traditional vibration-based diagnostic methods rely on direct sensor contact,leading to instal... Motor imbalance is a critical failure mode in rotating machinery,potentially causing severe equipment damage if undetected.Traditional vibration-based diagnostic methods rely on direct sensor contact,leading to installation challenges and measurement artifacts that can compromise accuracy.This study presents a novel radar-based framework for non-contact motor imbalance detection using 24 GHz continuous-wave radar.A dataset of 1802 experimental trials was sourced,covering four imbalance levels(0,10,20,30 g)across varying motor speeds(500–1500 rpm)and load torques(0–3 Nm).Dual-channel in-phase and quadrature radar signals were captured at 10,000 samples per second for 30-s intervals,preserving both amplitude and phase information for analysis.A multi-domain feature extraction methodology captured imbalance signatures in time,frequency,and complex signal domains.From 65 initial features,statistical analysis using Kruskal–Wallis tests identified significant descriptors,and recursive feature elimination with Random Forest reduced the feature set to 20 dimensions,achieving 69%dimensionality reduction without loss of performance.Six machine learning algorithms,Random Forest,Extra Trees Classifier,Extreme Gradient Boosting,Categorical Boosting,Support Vector Machine with radial basis function kernel,and k-Nearest Neighbors were evaluated with grid-search hyperparameter optimization and five-fold cross-validation.The Extra Trees Classifier achieved the best performance with 98.52%test accuracy,98%cross-validation accuracy,and minimal variance,maintaining per-class precision and recall above 97%.Its superior performance is attributed to its randomized split selection and full bootstrapping strategy,which reduce variance and overfitting while effectively capturing the nonlinear feature interactions and non-normal distributions present in the dataset.The model’s average inference time of 70 ms enables near real-time deployment.Comparative analysis demonstrates that the radar-based framework matches or exceeds traditional contact-based methods while eliminating their inherent limitations,providing a robust,scalable,and noninvasive solution for industrial motor condition monitoring,particularly in hazardous or space-constrained environments. 展开更多
关键词 Condition monitoring imbalance detection industrial applications machine learning motor fault diagnosis non-contact sensing radar sensing vibration monitoring
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Azobenzene-winged phenanthroline for supramolecular chirality sensing and multidimensional chiroptical manipulation via solvent,light,temperature,and redox
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作者 Xiaoqian Wang Yanling Shen +6 位作者 Long Chen Lizhi Fang Kuppusamy Kanagaraj Ming Rao Chunying Fan Wanhua Wu Cheng Yang 《Chinese Chemical Letters》 2026年第2期453-457,共5页
Azobenzene-winged phenanthrolines(L1 and L2)were designed,synthesized,and fully characterized.Ligand L1 forms an in-situ cobalt complex,which has been effectively employed as a circular dichroism(CD)-active chiral sen... Azobenzene-winged phenanthrolines(L1 and L2)were designed,synthesized,and fully characterized.Ligand L1 forms an in-situ cobalt complex,which has been effectively employed as a circular dichroism(CD)-active chiral sensor.The resulting ternary complex(L1-Co^(2+)-amino alcohol)exhibits pronounced exciton-coupled circular dichroism(ECCD)signals at the characteristic azobenzene absorption bands.These signals arise from efficient chirality transfer from the chiral amino alcohol to the azobenzene chromophores,enabling the determination of the absolute configuration of chiral amino alcohols.Accordingly,the L1-Co^(2+)coordination system demonstrates considerably potential in chirality sensing applications.Remarkably,the induced ECCD signals are highly responsive to multiple external stimuli,including photoirradiation,solvent polarity,temperature,and redox conditions.In particular,temperature and redox changes can induce a reversible inversion of the ECCD signal,thereby establishing this system as a multifunctional,stimuli-responsive chiroptical molecular switch. 展开更多
关键词 Phenanthroline derivative AZOBENZENE Amino alcohols Chirality sensing Stimuli-response
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Entropy-Driven Cellulosic Elastomer Self-Assembly for Mechanical Energy Harvesting and Self-Powered Sensing
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作者 Pinle Zhang Yingping He +5 位作者 Huancheng Huang Neng Xiong Xinyue Nong Xinke Yu Shuangfei Wang Xinliang Liu 《Nano-Micro Letters》 2026年第6期898-941,共44页
The rapid advancement of flexible electronics technology has placed higher demands on the structural design and performance regulation of elastic materials.Cellulosic elastomers,with their biodegradability,renewabilit... The rapid advancement of flexible electronics technology has placed higher demands on the structural design and performance regulation of elastic materials.Cellulosic elastomers,with their biodegradability,renewability,and tunability,emerge as ideal candidate materials.Entropy-driven self-as sembly promotes the spontaneous formation of ordered structures,serving as a crucial pathway for optimizing cellulose elastomer properties.However,the structure-property relationship between the self-assembled ordered structures of cellulose elastomers and their mechanical and electrical properties remains insufficiently explored.It hinders the expansion of their applications in electronic devices.This paper systematically reviews the structure-property regulation mechanisms of self-assembled cellulosic elastomers from an entropy-driven perspective.It elucidates the application principles and performance optimization strategies for mechanical energy harvesting and self-powered sensing,while also exploring the challenges and prospects for performance enhancement.This work provides a reference for the development of self-assembled cellulosic elastomers in the field of energy devices. 展开更多
关键词 Cellulosic elastomers Entropy-driven self-assembly Mechanoelectric conversion Self-powered sensing
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