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Dissolution kinetics of a low-grade oxide-sulfide copper ore with high silica content:Laboratory studies and statistical modeling
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作者 Hiva Farhadi Faramarz Doulati Ardejani +5 位作者 Sied Ziaedin Shafaei Tonkaboni Soroush Maghsoudy Roya Kafi Helia Tafakori Christoph Butscher Reza Taherdangkoo 《Acta Geochimica》 2026年第1期111-131,共21页
In this study,copper extraction from low-grade oxide-sulfide ores was investigated using a leaching method combined with response surface methodology(RSM)to optimize operational conditions and assess leaching kinetics... In this study,copper extraction from low-grade oxide-sulfide ores was investigated using a leaching method combined with response surface methodology(RSM)to optimize operational conditions and assess leaching kinetics.Given copper's extensive industrial applications,sustainable recovery from low-grade ores is critical.Five key parameters-acid concentration,leaching time,particle size,temperature,and solids percentage-were identified as major influences on copper recovery.The results revealed that leaching time and solids percentage,along with interactions between temperature-time and temperature-solids percentage,had the most significant effects.Optimal conditions for 80% copper recovery while minimizing iron recovery below 3% included an acid concentration of 1.21 mol L^(-1),a leaching time of 108 min,a particle size of 438μm,a temperature of 45℃,and a solids percentage of 18.2%.Leaching kinetics were analyzed using shrinking core models,with the Dickinson model best describing the process,showing an activation energy of 32.63 kJ mol^(-1),indicative of mixed diffusion and chemical reaction control.The final kinetic model effectively predicted the influence of key parameters.These findings highlight the importance of optimizing process variables and selecting suitable kinetic models to enhance extraction efficiency,reduce costs,and improve sustainability in copper recovery. 展开更多
关键词 Oxide-sulfi de ore Response surface methodology Kinetic analysis Miduk copper mine Shrinking core model Copper leaching
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In-situ collaborative design of crosslinking and fluorination toward poly(1,3-dioxolane)for high-performance semi-solid lithium metal batteries
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作者 Dezhi Yang Yaqiong Zhu +2 位作者 Yanan Yang Yiyang Sun Tao Zhang 《Journal of Energy Chemistry》 2026年第1期880-890,I0020,共12页
In-situ poly(1,3-dioxolane)(PDOL)-based electrolyte has received extensive attention in the research of lithium metal batteries due to its high stability to lithium anode and simple processing.However,it is still face... In-situ poly(1,3-dioxolane)(PDOL)-based electrolyte has received extensive attention in the research of lithium metal batteries due to its high stability to lithium anode and simple processing.However,it is still faced with defects such as low intrinsic ionic conductivity,a narrow electrochemical window,and poor thermal stability.A crosslinking and fluorination molecular design strategy toward PDOL is proposed to tackle the issues above.The amorphous crosslinked structure effectively improves ionic conductivity by inhibiting long-chain crystallization.Especially,the antioxidant–CF_(3)groups,stable crosslinked structure,and reduced terminal hydroxyl groups significantly enhance the electrochemical oxidation stability with a superb high-voltage window of 4.7 V.In addition,the designed electrolyte also exhibits obviously improved thermal stability with no deformation at 120°C for 5 min.Furthermore,the semi-solid NCM811||Li batteries exhibit a favourable capacity retention of 88.8%after 150 cycles at 0.5 C.Even assembled with NCM622 cathode working at 4.5 V,the semi-solid batteries can still show a satisfactory capacity retention of 85.3%after 100 cycles at 0.5 C.Also,a 0.1 Ah NCM811||Li pouch cell with active materials loading of 9 mg/cm2 demonstrates satisfactory cycling stability and working ability,which shows promising practical application prospects. 展开更多
关键词 Poly(1 3-dioxolane) CROSSLINKING FLUORINATION Lithium metal batteries
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Influences of Milling Degree on Zinc Bioavailability in Rice Grains Varied in Zinc and Phytic Acid Levels
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作者 HUO Shaojie LIN Jiaqi +3 位作者 SUN Yuxuan WU Dianxing SHU Xiaoli WANG Yin 《Rice science》 2026年第1期25-29,I0041-I0045,共10页
Zinc(Zn)deficiency is a global health issue,exacerbated by low Zn concentration and poor bioavailability in rice,primarily due to phytic acid(PA)interference.In this study,four doubled haploid(DH)progenies(DH1,DH11,DH... Zinc(Zn)deficiency is a global health issue,exacerbated by low Zn concentration and poor bioavailability in rice,primarily due to phytic acid(PA)interference.In this study,four doubled haploid(DH)progenies(DH1,DH11,DH18,and DH29)with distinct Zn and PA profiles were used to evaluate the effects of varying degrees of milling(DOM)on Zn bioavailability.Results showed DOM followed a double-exponential decay pattern(R^(2)>0.99)with milling time,varying among the four DH lines under identical milling conditions.As DOM increased,Zn,PA,and phosphorus(P)concentrations decreased progressively. 展开更多
关键词 zinc deficiency milling degree zinc bioavailability degrees milling dom double exponential decay pattern rice grains phytic acid
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基于MATLAB的变截面梁的振动特性分析
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作者 赵锐 陈霖 淡丹辉 《计算机仿真》 2025年第8期288-293,437,共7页
为分析变截面梁在弹性边界条件下的振动特性,提出了一种基于Timoshenko梁理论和修正Timoshenko梁理论的振动分析模型。通过改变梁两端弹簧的刚度来模拟不同边界条件,以谱几何法表示梁的控制函数,根据哈密顿原理并利用瑞利-里兹法计算变... 为分析变截面梁在弹性边界条件下的振动特性,提出了一种基于Timoshenko梁理论和修正Timoshenko梁理论的振动分析模型。通过改变梁两端弹簧的刚度来模拟不同边界条件,以谱几何法表示梁的控制函数,根据哈密顿原理并利用瑞利-里兹法计算变截面梁的振动特性。结果表明,对于低阶频率,两者得到的结果非常接近,对于高阶频率,修正Timoshenko梁理论的精度更高;几何参数对振动频率的影响较大,对1阶振型的影响较小;上述方法充分应用了三角函数的正交性,在保证计算精度的同时节约了计算资源;基于MATLAB开发了脱机计算程序,其简洁的可视化操作页面为实际工程应用提供了便利和理论依据。 展开更多
关键词 变截面 自振特性 谱几何法 修正铁摩辛柯梁
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基于改进DeepLabV3+网络的光伏组件热斑故障识别及状态量化评估方法研究 被引量:4
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作者 陈雷 刘波 +1 位作者 孙凯 赵健 《太阳能学报》 北大核心 2025年第3期445-453,共9页
针对光伏组件热斑的精确定位和量化评估,提出一种基于改进DeepLabV3+网络与热斑像素比重模型相融合的光伏组件状态量化评估方法,旨在实现不同热斑状态的量化评估。首先,基于获取的红外热斑图像集,提出在DeepLabV3+主干网络中引入迁移学... 针对光伏组件热斑的精确定位和量化评估,提出一种基于改进DeepLabV3+网络与热斑像素比重模型相融合的光伏组件状态量化评估方法,旨在实现不同热斑状态的量化评估。首先,基于获取的红外热斑图像集,提出在DeepLabV3+主干网络中引入迁移学习网络(EfficientNetB7)来提高热斑形状特征提取能力,进而实现热斑的像素级语义分割;其次,利用Canny算法对分割的热斑图像进行像素级轮廓界定,并利用格林积分计算其像素比重;最后,通过构建状态评估模型实现对光伏组件热斑状态的量化评估。现场试验表明,与常见的语义分割方法(DeepLabV3、FCN、U-net、Linknet、SegNet)相比,该文所提方法在像素准确率和平均交并比方面分别达到98.33%和91.43%,具有较好的热斑分割效果。此外,所提状态评估方法可实现对光伏组件热斑大小的准确量化评估。 展开更多
关键词 光伏组件 热斑 图像分割 状态评估 深度学习 红外图像
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基于Deeplabv3+和LK光流的动态视觉SLAM算法 被引量:1
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作者 周若轩 张瑞乾 +2 位作者 陈勇 袁旭浩 秦慧军 《电子测量技术》 北大核心 2025年第9期149-155,共7页
传统ORB-SLAM3系统在静态环境中表现优秀,但存在动态特征时会引入不必要的噪声,造成特征匹配出现错误,而现有动态SLAM算法难以完整判断潜在动态特征,出现漏检或误检导致定位精度下降。针对这些问题,将语义分割网络Deeplabv3+与LK光流法... 传统ORB-SLAM3系统在静态环境中表现优秀,但存在动态特征时会引入不必要的噪声,造成特征匹配出现错误,而现有动态SLAM算法难以完整判断潜在动态特征,出现漏检或误检导致定位精度下降。针对这些问题,将语义分割网络Deeplabv3+与LK光流法融合进ORB-SLAM3的跟踪线程,首先将Deeplabv3+的主干网络替换为Mobilenetv3,提高语义分割的精度,然后使用语义分割获取潜在动态目标掩码,初步滤除动态特征点,对剩余特征点进行LK光流计算,将光流平均误差作为阈值防止剩余静态特征点过少导致位姿估计失败。相比于原ORB-SLAM3,本文改进的算法在TUM高动态序列的定位精度平均提升了47.92%,与现有优秀动态SLAM算法相比,本文算法在TUM数据集的Walking_static序列取得了最高的定位精度。 展开更多
关键词 同时定位与地图构建 动态环境 语义分割 光流法
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Controllable synthesis of hydrogen-bonded organic framework encapsulated enzyme for continuous production of chiral hydroxybutyric acid in a two-stage cascade microreactor 被引量:1
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作者 Danyang Zhao Qiangqiang Xue +1 位作者 Yujun Wang Guangsheng Luo 《Chinese Journal of Chemical Engineering》 2025年第1期175-184,共10页
Constructing a framework carrier to stabilize protein conformation,induce high embedding efficiency,and acquire low mass-transfer resistance is an urgent issue in the development of immobilized enzymes.Hydrogen-bonded... Constructing a framework carrier to stabilize protein conformation,induce high embedding efficiency,and acquire low mass-transfer resistance is an urgent issue in the development of immobilized enzymes.Hydrogen-bonded organic frameworks(HOFs)have promising application potential for embedding enzymes.In fact,no metal involvement is required,and HOFs exhibit superior biocompatibility,and free access to substrates in mesoporous channels.Herein,a facile in situ growth approach was proposed for the self-assembly of alcohol dehydrogenase encapsulated in HOF.The micron-scale bio-catalytic composite was rapidly synthesized under mild conditions(aqueous phase and ambient temperature)with a controllable embedding rate.The high crystallinity and periodic arrangement channels of HOF were preserved at a high enzyme encapsulation efficiency of 59%.This bio-composite improved the tolerance of the enzyme to the acid-base environment and retained 81%of its initial activity after five cycles of batch hydrogenation involving NADH coenzyme.Based on this controllably synthesized bio-catalytic material and a common lipase,we further developed a two-stage cascade microchemical system and achieved the continuous production of chiral hydroxybutyric acid(R-3-HBA). 展开更多
关键词 Hydrogen-bonded organic framework Immobilized enzyme Synthesis Chiral hydroxycarboxylic acid BIOCATALYSIS Nanostructure
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基于ME-Deeplabv3+的车钩与风管分割技术研究
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作者 张世龙 王逸涵 +1 位作者 李柏林 郭彩玲 《计算机仿真》 2025年第8期197-203,共7页
针对现有模型对铁路货车车钩和风管分割精度较低、计算负担大的问题,提出一种车钩与风管分割模型ME-Deeplabv3+。首先,设计注意力机制模块和多尺度特征融合模块构建ME-MobileNetV2作为主干网络,提高特征信息提取能力;其次,设计e-DSConv... 针对现有模型对铁路货车车钩和风管分割精度较低、计算负担大的问题,提出一种车钩与风管分割模型ME-Deeplabv3+。首先,设计注意力机制模块和多尺度特征融合模块构建ME-MobileNetV2作为主干网络,提高特征信息提取能力;其次,设计e-DSConv模块替换空洞卷积,提高不同感受野下的特征信息利用率;最后,结合Dice Loss和Focal Loss替换CELoss,降低目标和背景像素比例不平衡的影响。实验结果表明:ME-Deeplabv3+具有较好的分割性能和较低的参数量,平均交并比86.08%,平均像素准确率91.68%,参数量4.055。相比Deeplabv3+,平均交并比和平均像素准确率提高5.66%和6.95%,参数量降低29.7%。 展开更多
关键词 精确分割 注意力机制 语义分割
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Digital Humanities,Computational Criticism and the Stanford Literary Lab:An Interviewwith Mark Algee-Hewittr
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作者 Hui Haifeng Mark Algee-Hewitt 《外国文学研究》 北大核心 2025年第4期1-10,共10页
The Literary Lab at Stanford University is one of the birthplaces of digital humanities and has maintained significant influence in this field over the years.Professor Hui Haifeng has been engaged in research on digit... The Literary Lab at Stanford University is one of the birthplaces of digital humanities and has maintained significant influence in this field over the years.Professor Hui Haifeng has been engaged in research on digital humanities and computational criticism in recent years.During his visiting scholarship at Stanford University,he participated in the activities of the Literary Lab.Taking this opportunity,he interviewed Professor Mark Algee-Hewitt,the director of the Literary Lab,discussing important topics such as the current state and reception of DH(digital humanities)in the English Department,the operations of the Literary Lab,and the landscape of computational criticism.Mark Algee-Hewitt's research focuses on the eighteenth and early nineteenth centuries in England and Germany and seeks to combine literary criticism with digital and quantitative analyses of literary texts.In particular,he is interested in the history of aesthetic theory and the development and transmission of aesthetic and philosophical concepts during the Enlightenment and Romantic periods.He is also interested in the relationship between aesthetic theory and the poetry of the long eighteenth century.Although his primary background is English literature,he also has a degree in computer science.He believes that the influence of digital humanities within the humanities disciplines is growing increasingly significant.This impact is evident in both the attraction and assistance it offers to students,as well as in the new interpretations it brings to traditional literary studies.He argues that the key to effectively integrating digital humanities into the English Department is to focus on literary research questions,exploring how digital tools can raise new questions or provide new insights into traditional research. 展开更多
关键词 digital humanities computational criticism literary research Literary Lab
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Epidemiological and Therapeutic Profile of Mastitis in Small Ruminants in the Labé Region (Guinea)
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作者 Lanan Wassy Soromou Gobou Lolahara +1 位作者 Hamani Marichatou André Delamou 《Journal of Biosciences and Medicines》 2025年第2期500-509,共10页
Mastitis is an inflammatory infection of the mammary glands that is frequently observed in animals. The aim of this study was to determine the prevalence of this infection, identify the pathogens responsible and highl... Mastitis is an inflammatory infection of the mammary glands that is frequently observed in animals. The aim of this study was to determine the prevalence of this infection, identify the pathogens responsible and highlight the risk factors in the region of Labé (Republic of Guinea). The survey involved 96 farmers in three prefectures (Koubia, Labé, Lélouma) and covered 3,199 animals, including 611 lactating females. The clinical survey revealed 49 suspected cases of mastitis, mainly in goats. The analysis showed a prevalence of clinical mastitis of 2.95% and a mortality rate of 18.35%. The identified risk factors were the hygiene of the premises, the age of the females, husbandry practices and the lack of regular veterinary care. 展开更多
关键词 Small Ruminants MASTITIS Prevalence Labé
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BIG-ABAC:Leveraging Big Data for Adaptive,Scalable,and Context-Aware Access Control
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作者 Sondes Baccouri Takoua Abdellatif 《Computer Modeling in Engineering & Sciences》 2025年第4期1071-1093,共23页
Managing sensitive data in dynamic and high-stakes environments,such as healthcare,requires access control frameworks that offer real-time adaptability,scalability,and regulatory compliance.BIG-ABAC introduces a trans... Managing sensitive data in dynamic and high-stakes environments,such as healthcare,requires access control frameworks that offer real-time adaptability,scalability,and regulatory compliance.BIG-ABAC introduces a transformative approach to Attribute-Based Access Control(ABAC)by integrating real-time policy evaluation and contextual adaptation.Unlike traditional ABAC systems that rely on static policies,BIG-ABAC dynamically updates policies in response to evolving rules and real-time contextual attributes,ensuring precise and efficient access control.Leveraging decision trees evaluated in real-time,BIG-ABAC overcomes the limitations of conventional access control models,enabling seamless adaptation to complex,high-demand scenarios.The framework adheres to the NIST ABAC standard while incorporating modern distributed streaming technologies to enhance scalability and traceability.Its flexible policy enforcement mechanisms facilitate the implementation of regulatory requirements such as HIPAA and GDPR,allowing organizations to align access control policies with compliance needs dynamically.Performance evaluations demonstrate that BIG-ABAC processes 95% of access requests within 50 ms and updates policies dynamically with a latency of 30 ms,significantly outperforming traditional ABAC models.These results establish BIG-ABAC as a benchmark for adaptive,scalable,and context-aware access control,making it an ideal solution for dynamic,high-risk domains such as healthcare,smart cities,and Industrial IoT(IIoT). 展开更多
关键词 ABAC big data CONTEXT-AWARE decision trees adaptive policy SCALABILITY
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Exploring a novel approach to assessing surgical team collaboration:Evidence of brain activity synchronization
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作者 Shuyi(Kiana)Wang Ghazal Hashemi +1 位作者 Yao Zhang Bin Zheng 《Laparoscopic, Endoscopic and Robotic Surgery》 2025年第1期6-12,共7页
Objective:Interpersonal brain synchronization(IBS)has emerged as a significant concept in understanding collaborative team dynamics,with functional near-infrared spectroscopy(fNIRS)proving to be a vital tool in its as... Objective:Interpersonal brain synchronization(IBS)has emerged as a significant concept in understanding collaborative team dynamics,with functional near-infrared spectroscopy(fNIRS)proving to be a vital tool in its assessment.This review aims to collate and analyze the literature on the application of fNIRS in various team settings,emphasizing its potential utility in surgical environments.Methods:A thorough search and screening process across multiple databases resulted in 17 studies being reviewed,with a focus on the utilization of fNIRS to measure IBS in different collaborative tasks.This review examined the tasks employed,participant demographics,organizational structures of teams,methodologies for IBS measurement,and correlations between brain synchronization and behavioral measurements.Results:fNIRS emerged as a non-invasive,cost-effective,and portable tool,predominantly used to assess IBS in pair-based tasks with a variety of participant demographics.Wavelet transform coherence was the primary method used for measuring synchronization,particularly in the prefrontal brain region.A consistent correlation was found between increased brain synchronization and enhanced team performance,underscoring the potential of fNIRS in understanding and optimizing team dynamics.Conclusion:This review establishes fNIRS as a promising tool for investigating the neural mechanisms underlying team cooperation,providing invaluable insights for potential applications in surgical settings.While acknowledging the limitations in the current literature,the review highlights the need for further research with larger sample sizes and varied task complexities to solidify the understanding of IBS and its impact on team performance.The ultimate goal is to leverage fNIRS in assessing and improving surgical team dynamics,contributing to improved patient outcomes and safety. 展开更多
关键词 Functional near-infrared spectroscopy Interpersonal brain synchronization Team cognition Team performance Surgical team training
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Droplet-Enabled Controllable Manipulation of Tribo-Charges from Liquid-Solid Interface 被引量:1
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作者 Xunjia Li Jianjun Luo +1 位作者 Jianfeng Ping Zhong Lin Wang 《Engineering》 2025年第2期132-142,共11页
Efficient utilization of electrostatic charges is paramount for numerous applications,from printing to kinetic energy harvesting.However,existing technologies predominantly focus on the static qualities of these charg... Efficient utilization of electrostatic charges is paramount for numerous applications,from printing to kinetic energy harvesting.However,existing technologies predominantly focus on the static qualities of these charges,neglecting their dynamic capabilities as carriers for energy conversion.Herein,we report a paradigm-shifting strategy that orchestrates the swift transit of surface charges,generated through contact electrification,via a freely moving droplet.This technique ingeniously creates a bespoke charged surface which,in tandem with a droplet acting as a transfer medium to the ground,facilitates targeted charge displacement and amplifies electrical energy collection.The spontaneously generated electric field between the charged surface and needle tip,along with the enhanced water ionization under the electric field,proves pivotal in facilitating controlled charge transfer.By coupling the effects of charge self-transfer,contact electrification,and electrostatic induction,a dual-electrode droplet-driven(DD)triboelectric nanogenerator(TENG)is designed to harvest the water-related energy,exhibiting a two-orderof-magnitude improvement in electrical output compared to traditional single-electrode systems.Our strategy establishes a fundamental groundwork for efficient water drop energy acquisition,offering deep insights and substantial utility for future interdisciplinary research and applications in energy science. 展开更多
关键词 Solid-liquid interface engineering Energy harvesting device Triboelectric nanogenertor Interface charge utilization Water energy
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地图学的社会实践范式构建
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作者 苏世亮 谢丹明 +3 位作者 杜清运 李霖 翁敏 亢孟军 《地球信息科学学报》 北大核心 2026年第1期42-54,共13页
【背景】近年来,面对地图实践的新现象和新问题,越来越多的学者呼吁重新审视和反思既有范式的不足,并以此回应技术变革所带来的学科挑战与社会需求。【目标与方法】秉承批判继承与创新超越相结合的研究路径,本文通过理论演绎的方法,首... 【背景】近年来,面对地图实践的新现象和新问题,越来越多的学者呼吁重新审视和反思既有范式的不足,并以此回应技术变革所带来的学科挑战与社会需求。【目标与方法】秉承批判继承与创新超越相结合的研究路径,本文通过理论演绎的方法,首先对地图学的既有理论范式进行梳理和凝练,进而剖析其面对地图实践结构转型时遭遇的困境,最后尝试提出地图学的新范式。【结果】经典地图学研究将“地图”等同于特定专业和行业规范下的制图活动,促成了地图学在知识来源、关注焦点和实践路径等方面所呈现出鲜明的专业生产特征,并以此形成了地图学的专业生产范式。然而,专业生产范式逐渐显露出两个突出的困境。一方面,专业生产范式难以捕捉地图嵌入社会生活中的复杂性与流动性,尤其是用于解释地图实践的新形式及其所关联的意义机制时,往往陷入适配失效与理论滞后的窘境。另一方面,专业生产范式局限在一种内部的知识再生产,缺乏实质性的理论增量与问题意识的深化,无法为当前的地图实践提供规范与引导。鉴于此,本研究立足于世界的网络化、关系化特征,尝试提出地图学的社会实践范式,将地图视为嵌入社会网络、关联社会行动者的社会实践,关注地图在连接个体与外部世界中的独特意义与社会价值。【结论】社会实践范式立足于超越性的视野理解和认识地图,引入多学科融合和多元方法路径研究地图,倡导本土经验与国际视野的协调统一,不仅深化了对地图实践的整体性理解,也为地图学回应当代数字社会、智能社会与网络社会中的现实问题提供了新的理论资源与分析框架。 展开更多
关键词 地图 地图学 地图学范式 理论范式 地图学理论 理论地图学
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A Laboratorial Testing Scheme for 5G System:Channel Model Principle and Field Experiment Validation
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作者 Zhang Yuxiang Zhang Jianhua +7 位作者 Kang Yanan Zhao Mengxuan Qi Pan Zhang Zhen Tang Pan Tian Lei Liu Guangyi Yao Yuan 《China Communications》 2025年第9期113-128,共16页
As the commercialization of the fifth gen-eration communication(5G)is sped up,its system testing scheme is vital for the successful deployment of 5G.Especially,5G relies on the scale-increased multiple-input-multiple ... As the commercialization of the fifth gen-eration communication(5G)is sped up,its system testing scheme is vital for the successful deployment of 5G.Especially,5G relies on the scale-increased multiple-input-multiple output(MIMO)technique to improve its capacity and coverage.Thus,testing new functions of the 5G MIMO system accurately and ef-ficiently,including beamforming(beam-tracking with movement)and multiple-user(MU)multiplexing,is a challenging task.This paper tries to construct a lab-oratorial hardware and conduct equipment-controlled field testing.Firstly,the testing scheme is presented,which is composed of the framework,the channel models and the validation methods.Then,the channel model principles are explained in detail due to its di-rect influence on the testing accuracy.Specifically,we utilize the spatial consistency and the multi-link cor-relation properties to emulate the high-speed dynamic time-varying(HDT)and the multiple-cell(MC)-MU-MIMO channels.Finally,the above testing scheme is verified in a Shanghai 5G field experiment with the practical commercial equipment and the channel em-ulator.The results show that the 5G new functions are tested accurately and efficiently by switching the channel emulation configurations. 展开更多
关键词 channel model field experiment high-speed dynamic time-varying(HDT) multiple-cell-multiple-user-multiple-input-multiple-output(MC-MU-MIMO) testing scheme the fifth generation communication(5G)
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Recent advances of sustainable and recyclable polymer materials from renewable resources
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作者 Ting Luo Yun Hu +2 位作者 Meng Zhang Puyou Jia Yonghong Zhou 《Resources Chemicals and Materials》 2025年第2期13-23,共11页
With the increasing consumption of non renewable resources such as oil,the traditional polymer manufacturing industry that relies on fossil resources is facing unprecedented challenges.The design,synthesis,and recycli... With the increasing consumption of non renewable resources such as oil,the traditional polymer manufacturing industry that relies on fossil resources is facing unprecedented challenges.The design,synthesis,and recycling of renewable and environmentally friendly bio-based polymers as alternatives to petroleum based polymers have become hot topics in research and industrial fields.Biomass has been used as a raw material to design and synthesize closed-loop recyclable polymers,which is of great significance in addressing the waste of resources and negative impact on the environment in the traditional polymer preparation process.This review summarized recent advances in the design,synthesis,and properties of closed-loop recyclable bio-based polymers,focusing on the sustainability and recyclability of bio-based materials,followed by a brief discussion of the potential applications of closed-loop recyclable bio-based polymers in emerging applications such as 3D printing and friction electric nanogenerators.In addition,perspectives and recommendations for future research on closedloop recyclable bio-based polymers were presented. 展开更多
关键词 Bio-based polymer Closed-loop recycling Dynamic crosslinking Chemical recycling
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高粱紫色叶突变体sbsn1的表型及理化特性分析
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作者 李丹 朱振兴 +1 位作者 陆晓春 马殿荣 《分子植物育种》 北大核心 2026年第3期853-857,共5页
采用EMS诱变野生型高粱BTx623种子的方法获得紫色叶突变体。以野生型BTx623为对照,进行成熟期农艺性状调查和苗期生理生化指标测定。结果表明,sbsn1与BTx623相比,穗长、穗柄长、株高、粒数、千粒重和穗宽均极显著降低,茎粗和节数极显著... 采用EMS诱变野生型高粱BTx623种子的方法获得紫色叶突变体。以野生型BTx623为对照,进行成熟期农艺性状调查和苗期生理生化指标测定。结果表明,sbsn1与BTx623相比,穗长、穗柄长、株高、粒数、千粒重和穗宽均极显著降低,茎粗和节数极显著增加,突变体sbsn1的粒数降低到BTx623的1/2,抽穗期延后了20~30 d。缺氮条件下苗期叶片叶绿素测定结果显示,突变体sbsn1叶绿素降低幅度大于BTx623,初步推断出缺氮可能导致依赖光的光合作用能力减弱、使叶片中的叶绿素含量降低;突变体sbsn1叶片花青素含量、可溶性糖及总淀粉含量在缺氮条件下极显著高于BTx623。说明突变体sbsn1具有较强的抵抗缺氮逆境能力以维持自身正常生长。高粱作为C_(4)植物,光合效率高,耐瘠薄,养分和水分利用效率是C_(3)作物的2倍,但是对高粱养分吸收利用机制研究较少,本研究通过对高粱氮缺乏条件下根伸长不敏感突变体sbsn1,进行农艺性状以及苗期理化特性的测定,为下一步新基因定位以及基因功能的研究提供重要依据。 展开更多
关键词 高粱 紫色叶突变体 农艺性状 生理生化特性
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青少年特质感恩与主观幸福感:生命意义的纵向解释作用 被引量:1
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作者 李丹 陈佳宇 +2 位作者 刘思格 吴德华 尹华站 《心理发展与教育》 北大核心 2026年第1期28-38,共11页
本研究旨在考察青少年特质感恩、生命意义与主观幸福感的发展轨迹,并进一步探讨三者之间的动态关系以及生命意义的纵向解释作用。采用自陈报告式调查问卷对湖南省764名中学生进行为期一年共三次的追踪调查,建立多元潜变量增长模型进行... 本研究旨在考察青少年特质感恩、生命意义与主观幸福感的发展轨迹,并进一步探讨三者之间的动态关系以及生命意义的纵向解释作用。采用自陈报告式调查问卷对湖南省764名中学生进行为期一年共三次的追踪调查,建立多元潜变量增长模型进行分析。结果发现:(1)青少年特质感恩、存在意义及主观幸福感均呈线性显著性递增,追寻意义呈线性显著性递减;(2)特质感恩的初始水平显著正向预测主观幸福感的初始水平,特质感恩的发展速度正向预测主观幸福感的发展速度;(3)在初始水平上,青少年存在意义与追寻意义均在特质感恩与主观幸福感之间起完全中介作用;而在发展速度上,仅存在意义在特质感恩与主观幸福感之间起完全中介作用。这意味着特质感恩初始水平通过存在意义和追寻意义进一步影响主观幸福感的初始水平;特质感恩的发展速度通过存在意义进一步影响主观幸福感的发展速度。这对把握青少年心理发展的关键期,保障心理健康发展具有一定的现实指导意义。 展开更多
关键词 青少年 特质感恩 存在意义 追寻意义 主观幸福感 多元潜变量增长模型
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Retrieval of Surface Soil Moisture Using Landsat 8 TIRS Data:A Case Study of Faisalabad
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作者 Uzair Abbas Zahid Maqbool +2 位作者 Muhammad Adnan Shahid Muhammad Safdar Saif Ullah Khan 《Revue Internationale de Géomatique》 2025年第1期655-668,共14页
This study was conducted to devise an integrated methodology for retrieval of surface soilmoisture(SSM)using Landsat 8 TIRS data.For this purpose,Landsat 8 images of 15 May 2021(pre-monsoon)and 20 November 2021(post-m... This study was conducted to devise an integrated methodology for retrieval of surface soilmoisture(SSM)using Landsat 8 TIRS data.For this purpose,Landsat 8 images of 15 May 2021(pre-monsoon)and 20 November 2021(post-monsoon)were processed for retrieval of soil moisture index(SMI)based on land surface temperature(LST).Moreover,field-based SM in the laboratory was also determined and correlated with satellite-based SMI.A moderate correlation between field-based SM and satellite-based SMI with R2=0.60 was obtained.Based on this relationship,SSM maps of Tehsil Faisalabad Saddar for the pre-and post-monsoon seasons of 2021 were developed.Significant variations in the spatial distribution of SSM of Tehsil Faisalabad Saddar(total area of 1492.45 km^(2))for pre-and postmonsoon seasons were observed.In the pre-monsoon season,68.1% of the area of Faisalabad Saddar showed SSM contents ranging from 10.37%to 15.40%.Only 8.7%of the total area of Faisalabad Saddar exhibited SSM in the range of 15.41%-22.82%in the pre-monsoon season.It was astonishing to notice that no area in Faisalabad Saddar was detected with SSMabove 22.82% in the pre-monsoon season.However,in the post-monsoon season,only 0.11%of the total study area exhibited SSM in the range of 0.0%to 26.97%.The maximum area(52.29%of the total area)in post-monsoon season exhibited SSMranging from 36.18%to 40.02%,followed by 32.02%-36.17%(34.3% of the total area).The study concluded that satellite-based retrieval of surface soil moisture realistically monitored the variations in soil moisture due to the onset of the monsoon season.The novel methodology developed in this study could be helpful for policy making regarding groundwater recharge and its sustainable use in an area,as well as for estimating surface soilmoisture to provide irrigation scheduling and crop management guidelines. 展开更多
关键词 Soil moisture index(SMI) spatio-temporal changes GIS remote sensing Landsat 8 TIRS land surface temperature(LST)
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Different extractable pools of Cd and Pb in agricultural soil under amendments:Water-soluble concentration sensitively indicates metal availability 被引量:1
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作者 Zidi Wang Wenyao Tang +8 位作者 Xiaodong Ding Qiang Dong Yingying Guo Guangliang Liu Yanwei Liu Yong Liang Yongguang Yin Yong Cai Guibin Jiang 《Journal of Environmental Sciences》 2025年第4期297-308,共12页
Identification of the most appropriate chemically extractable pool for evaluating Cd and Pb availability remains elusive,hindering accurate assessment on environmental risks and effectiveness of remediation strategies... Identification of the most appropriate chemically extractable pool for evaluating Cd and Pb availability remains elusive,hindering accurate assessment on environmental risks and effectiveness of remediation strategies.This study evaluated the feasibility of European Community Bureau of Reference(BCR)sequential extraction,Ca(NO_(3))_(2)extraction,and water extraction on assessing Cd and Pb availability in agricultural soil amended with slaked lime,magnesium hydroxide,corn stover biochar,and calcium dihydrogen phosphate.Moreover,the enriched isotope tracing technique(^(112)Cd and^(206)Pb)was employed to evaluate the aging process of newly introduced Cd and Pbwithin 56 days’incubation.Results demonstrated that extractable pools by BCR and Ca(NO_(3))_(2)extraction were little impacted by amendments and showed little correlation with soil pH.This is notable because soil pH is closely linked to metal availability,indicating these extraction methods may not adequately reflect metal availability.Conversely,water-soluble concentrations of Cd and Pb were markedly influenced by amendments and exhibited strong correlations with pH(Pearson’s r:-0.908 to-0.825,P<0.001),suggesting water extraction as a more sensitive approach.Furthermore,newly introduced metals underwent a more evident aging process as demonstrated by acid-soluble and water-soluble pools.Additionally,water-soluble concentrations of essential metals were impacted by soil amendments,raising caution on their potential effects on plant growth.These findings suggest water extraction as a promising and attractive method to evaluate Cd and Pb availability,which will help provide assessment guidance for environmental risks caused by heavy metals and develop efficient remediation strategies. 展开更多
关键词 Heavy metals Water-soluble concentrations Enriched stable isotopes Soil amendments Sequential extraction Soil pH
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