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Residual levels and health risk assessment of trace metals in Chinese resident diet

Journal of Environmental Sciences 2024年第2期136卷 451-459页

作者： Yubing Dai Shuai Sun Rong Cao haijun zhang Jiping Chen Ningbo Geng CAS Key Laboratory of Separation Science for Analytical Chemistry Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Shenyang Pharmaceutical University Shenyang 110016China University of Chinese Academy of Sciences Beijing 100049China

Large-scale metal contamination across the food web is an intractable problem due to increasing pollutant emissions,atmospheric transport,and dry and wet deposition of *** present study focus on several trace metals that are rarely studied but have special toxicity,including tin(Sn),antimony(Sb),gold(Au),hafnium(Hf),palladium(Pd),platinum(Pt),ruthenium(Ru),tellurium(Te)and iridium(Ir).We investigated trace metals residues and distribution characteristics,and further evaluated the potential health risks from major daily food intakes in 33 cities in ***,Sb,Ir,Hf,and Au were frequently detected in food samples with the concentrations ranged from ND(not detected)to 24.78μg/kg ww(wet weight).Eggs exhibited the highest residual level of all detected metals(13.70±14.70μg/kg ww in sum),while the lowest concentrations were observed in vegetables(0.53±0.17μg/kg ww in sum).Sn accounting for more than 50%of the total trace metals concentration in both terrestrial and aquatic animal origin *** terrestrial plant origin foods,Sn and Ir were the most abundant *** and Au were the most abundant elements in egg *** addition,Sb and Ir showed a clear trophic dilution effect in terrestrial environments,while in aquatic ecosystems,Sn,Hf,and Au exhibited obvious trophic amplification *** calculated average estimated daily intake(EDI)via food consumption in five regions of China was 0.09μg/(kg·day),implying the health risk of aforementioned elements was acceptable.

关键词： Trace metals Accumulation characteristics Dietary exposure Estimated daily intake(EDI)

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Wireless semantic communication based on semantic matching multiple access and intent bias multiplexing

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The Journal of China Universities of Posts and Telecommunications 2024年第1期31卷 26-36页

作者： Ren Chao He Zongrui Sun Chen Li Haojin zhang haijun University of Science and Technology Beijing Beijing 100083China Research and Development Center Sony(China)LimitedBeijing 100027China

This paper proposes a multi-access and multi-user semantic communication scheme based on semantic matching and intent deviation to address the increasing demand for wireless users and *** scheme enables flexible management of long frames,allowing each unit of bandwidth to support a higher number of *** leveraging semantic classification,different users can independently access the network through the transmission of long concatenated sequences without modifying the existing wireless communication *** overcome the potential disadvantage of incomplete semantic database matching leading to semantic intent misunderstanding,the scheme proposes using intent deviation as an *** allows different receivers to interpret the same semantic information differently,enabling multiplexing where one piece of information can serve multiple users with distinct *** results show that at a bit error rate(BER)of 0.1,it is possible to reduce the transmission by approximately 20 semantic basic units.

关键词： semantic communication multiple access multiplexing multimodal communication

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Decreased eggshell strength caused by impairment of uterine calcium transport coincide with higher bone minerals and quality in aged laying hens

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Journal of Animal Science and Biotechnology 2024年第3期15卷 1258-1277页

作者： Yu Fu Jianmin Zhou Martine Schroyen haijun zhang Shugeng Wu Guanghai Qi Jing Wang Key Laboratory of Feed Biotechnology Ministry of Agriculture and Rural AffairsInstitute of Feed ResearchChinese Academy of Agricultural SciencesBeijing 100081China Precision Livestock and Nutrition Laboratory Gembloux Agro‑Bio TechTERRA Teaching and Research CentreUniversity of LiegeGembloux B‑5030Belgium

Background Deteriorations in eggshell and bone quality are major challenges in aged laying *** study compared the differences of eggshell quality,bone parameters and their correlations as well as uterine physiologi-cal characteristics and the bone remodeling processes of hens laying eggs of different eggshell breaking strength to explore the mechanism of eggshell and bone quality reduction and their interaction.A total of 24074-week-old Hy-line Brown laying hens were selected and allocated to a high(HBS,44.83±1.31 N)or low(LBS,24.43±0.57 N)eggshell breaking strength *** A decreased thickness,weight and weight ratio of eggshells were observed in the LBS,accompanied with ultrastructural deterioration and total Ca *** quality was negatively correlated with eggshell quality,marked with enhanced structures and increased components in the *** the LBS,the mammillary knobs and effective layer grew *** the initiation stage of eggshell calcification,a total of 130 differentially expressed genes(DEGs,122 upregulated and 8 downregulated)were identified in the uterus of hens in the LBS relative to those in the *** DEGs were relevant to apoptosis due to the cellular Ca *** values of p62 protein level,caspase-8 activity,Bax protein expression and lower values of Bcl protein expression and Bcl/Bax ratio were seen in the *** assay and hematoxylin-eosin staining showed a significant increase in TUNEL-positive cells and tissue damages in the uterus of the *** few DEGs were identified at the growth stage,similar uterine tissue damages were also observed in the *** expressions of runt-related transcription factor 2 and osteocal-cin were upregulated in humeri of the *** diameter and more structural damages of endocortical bones and decreased ash were observed in femurs of the *** The lower eggshell breaking strength may be attributed to a declined Ca transport due to uterine tissue damages,which

关键词： Bone parameter Calcium transport Eggshell quality Laying hen Tissue damage

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Experimental observation of multiple topological nodal structure in LaSb_(2)

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 138-145页

作者： Yuxi Qiao Fuyi Wang Huaiqiang Wang Zicheng Tao Zhicheng Jiang Zhengtai Liu Soohyun Cho Fayuan zhang Qingkai Meng Wei Xia Yichen Yang Zhe Huang Jishan Liu Zhonghao Liu Zengwei Zhu Shan Qiao Yanfeng Guo haijun zhang Dawei Shen State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China National Synchrotron Radiation Laboratory and School of Nuclear Science and TechnologyUniversity of Science and Technology of ChinaHefei 230026China National Laboratory of Solid State Microstructures School of PhysicsNanjing UniversityNanjing 210093China School of Physics and Technology Nanjing Normal UniversityNanjing 210023China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201210China Shenzhen Institute for Quantum Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Wuhan National High Magnetic Field Center and School of Physics Huazhong University of Science and TechnologyWuhan 430074China ShanghaiTech Laboratory for Topological Physics ShanghaiTech UniversityShanghai 201210China Institute of High-Pressure Physics School of Physical Science and Technology Ningbo UniversityNingbo 315211China Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Unconventional fermions in the immensely studied topological semimetals are the source for rich exotic topological ***,using symmetry analysis and first-principles calculations,we propose the coexistence of multiple topological nodal structure in LaSb_(2),including topological nodal surfaces,nodal lines and in particular eightfold degenerate nodal points,which have been scarcely observed in a single ***,utilizing angle-resolved photoemission spectroscopy,we confirm the existence of nodal surfaces and eightfold degenerate nodal points in LaSb_(2).The intriguing multiple topological nodal structure might play a crucial role in giving rise to the large linear *** work renews the insights into the exotic topological phenomena in LaSb_(2).

关键词： eightfold degenerate points multiple topological nodal structure angle-resolved photoemission spectroscopy linear unsaturated magnetoresistance

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Characterization of ultraviolet communication in a mixed aerosol environment

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Optoelectronics Letters 2024年

作者： ZHAO Taifei SUN Yuxin WANG Wuxin zhang haijun PAN Feixiang WU Hao Artificial Intelligence Key Laboratory of Sichuan Province Sichuan University of Science & Engineering Faculty of Automation and Information Engineering Xi'an University of Technology

Wireless ultraviolet has strong scattering characteristics and can communicate through non-direct vision. When UV signals are transmitted in the atmosphere， they are affected by the absorption and scattering effects of atmospheric particles and atmospheric turbulence， resulting in attenuation of UV signal energy and reduced reliability of the communication system. This paper focuses on the channel model of UV non-direct-view single scattering communication， and simulates and analyzes the communication characteristics of UV light in atmospheric turbulence and mixed aerosol environment under horizontal， vertical and oblique range communication scenarios. The results show that at equal relative humidity， the wireless UV non-directive scattering communication performance for vertical communication scenarios is more affected by the mixed aerosol environment and the communication performance is worse.

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6G无线多模态通信技术

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电子与信息学报 2024年第5期46卷 1658-1671页

作者：任超丁思颖张晓奇张海君北京科技大学北京100083

该文综述了多模态通信作为一种能够同时交互多种模态形式的信息转移方式在不同应用场景下的重要性及其未来在6G无线通信技术中的发展前景。首先,将多模态通信分为3类,并探讨了其在这些领域中的关键作用。随后,针对6G无线通信系统可能面... 详细信息

该文综述了多模态通信作为一种能够同时交互多种模态形式的信息转移方式在不同应用场景下的重要性及其未来在6G无线通信技术中的发展前景。首先,将多模态通信分为3类,并探讨了其在这些领域中的关键作用。随后,针对6G无线通信系统可能面临的通信、感知、计算和存储资源限制以及跨域资源管理问题进行了深入剖析,指出未来的6G无线多模态通信将实现通感算存的深度融合和通信能力的提升。在多模态通信实现过程中,必须考虑多个环节,包括多发送端处理、传输技术和接收端处理等,以解决多模态语料库构建、多模态信息压缩、传输、干扰处理、降噪、对齐、融合和扩充等方面的挑战,以及资源管理问题。最后,强调了6G网络的跨域多模态信息转移、互补和协同的重要性,这将更好地整合和应用海量异构信息,以满足未来高速、低延迟、智能互联的通信需求。

关键词：多模态通信多媒体信息无线通信技术

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一种基于数据增强的科技文献关键词提取模型

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情报杂志 2024年第1期43卷 135-141,120页

作者：程芮张海军新疆师范大学计算机科学技术学院乌鲁木齐830054

[研究目的]科技文献关键词提取研究具有重要价值,目前研究中关键词提取方法存在较大误差且只能提取文本中的关键词,难以根据深层语义信息提炼出更符合文本核心主旨的词语。本研究针对关键词提取对上下文隐含语义挖掘不足导致的局限性和... 详细信息

[研究目的]科技文献关键词提取研究具有重要价值,目前研究中关键词提取方法存在较大误差且只能提取文本中的关键词,难以根据深层语义信息提炼出更符合文本核心主旨的词语。本研究针对关键词提取对上下文隐含语义挖掘不足导致的局限性和重点信息关注不足问题开展研究。[研究方法]提出一种基于数据增强的关键词提取模型(GPT-2 BiLSTM Mul-Attention,GPBA),通过语言模型进行数据增强,并结合BiLSTM+Mul-Attention提取模型进行多特征语义信息融合理解。[研究结论]实验结果表明,基于数据增强的关键词提取模型GPBA总体表现优于其他基线模型,并且能更精确地凝练和提取文本中的关键词。

关键词：科技文献关键词提取模型数据增强语义信息评估指标

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高熵合金纳米电催化剂的合成

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稀有金属 2024年第1期48卷 90-104页

作者：薛天雨黄仲谷昊辉张海军武汉科技大学材料学部省部共建耐火材料与冶金国家重点实验室湖北武汉430081

相较于单金属和双金属催化剂,高熵合金(HEAs)催化剂因具有多种活性位点而表现出优异的协同效应和催化活性,当其粒径细化至纳米尺度时,纳米尺寸效应与多元活性位点赋予了高熵合金纳米颗粒(np-HEAs)催化剂较低的过电位,近年来在电化学领... 详细信息

相较于单金属和双金属催化剂,高熵合金(HEAs)催化剂因具有多种活性位点而表现出优异的协同效应和催化活性,当其粒径细化至纳米尺度时,纳米尺寸效应与多元活性位点赋予了高熵合金纳米颗粒(np-HEAs)催化剂较低的过电位,近年来在电化学领域逐渐成为研究热点。目前,np-HEAs催化剂的合成方法有脱合金法、热冲击法、低温液相共还原法、机械合金法、激光烧蚀法及溅射沉积法等。综述了近年来np-HEAs催化剂合成的研究现状,总结了提高其催化活性的策略及措施,并展望了np-HEAs催化剂的未来发展方向。

关键词：高熵合金(HEAs) 高熵合金纳米颗粒(np-HEAs) 催化剂纳米尺寸效应

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木质纤维素气凝胶制备及阻燃改性

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化学进展 2024年第4期36卷 586-600页

作者：王爽张鑫孙苗段红娟张海军李少平武汉科技大学省部共建耐火材料与冶金国家重点实验室武汉430081 湖北三峡实验室宜昌443007

木质纤维素气凝胶具有密度低、孔隙率高、导热系数低等优异性能,被广泛应用于保温隔热、吸附、催化、电磁屏蔽和生物医学等领域。同时木质纤维素也是一种生物基材料,具有绿色、无污染、可再生和可持续的特点。本文首先综述了木材基纤维... 详细信息

木质纤维素气凝胶具有密度低、孔隙率高、导热系数低等优异性能,被广泛应用于保温隔热、吸附、催化、电磁屏蔽和生物医学等领域。同时木质纤维素也是一种生物基材料,具有绿色、无污染、可再生和可持续的特点。本文首先综述了木材基纤维素和农作物废弃物基纤维素气凝胶的最新研究进展,然后综述了冷冻干燥、超临界干燥和常压干燥制备木质纤维素气凝胶的研究现状。其次,针对木质纤维素气凝胶普遍存在的易燃问题,详述了提高木质纤维素气凝胶阻燃性能的常用方法。最后,提出了木质纤维素气凝胶制备及性能方面存在的主要问题,并对该领域未来的发展方向进行了展望。

关键词：气凝胶木质纤维素干燥技术阻燃性能

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基于多目标遗传算法的消声器结构优化研究

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内蒙古农业大学学报（自然科学版） 2024年第1期45卷 27-33页

作者：张海军苏赫武佩湖州职业技术学院智能制造与电梯学院湖州313099 内蒙古农业大学机电工程学院呼和浩特010018 湖州市新能源电驱动技术重点实验室湖州313099

针对柴油机插入管排气消声器宽频段(0~1300 Hz)和低频段(0~800 Hz)消声效果不佳的情况,本文提出一种基于多目标的消声器结构优化方法。首先,联合采用有限元法与多元统计方法,建立基于结构参数的插入管排气消声器压力损失函数。其次,基... 详细信息

针对柴油机插入管排气消声器宽频段(0~1300 Hz)和低频段(0~800 Hz)消声效果不佳的情况,本文提出一种基于多目标的消声器结构优化方法。首先,联合采用有限元法与多元统计方法,建立基于结构参数的插入管排气消声器压力损失函数。其次,基于一维平面波理论建立插入管排气消声器宽频传递损失函数和低频传递损失函数。最后,以压力损失、宽频传递损失和低频传递损失为优化目标,采用多目标优化遗传算法(NSGA-II)进行消声器结构优化,得到了最优结构参数组合。试验结果表明:优化后的消声器既提高了传递损失,又降低了压力损失。优化后消声器的低频传递损失和宽频传递损失比优化前分别提高了4.44 dB和8.10 dB,提高率分别为42.05%和80.52%;压力损失比优化前降低了181.9 Pa,降低率为5.49%。本文建立的基于多目标遗传算法的消声器结构优化方法可为插入管排气消声器的优化设计提供理论依据。

关键词：内燃机消声器压力损失多目标优化

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