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Creep-Resistant Covalent Adaptable Networks with Excellent Selfhealing and Reprocessing Performance via Phase-Locked Dynamic Covalent Benzopyrazole-Urea Bonds

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Chinese Journal of Polymer Science 2024年第10期42卷 1545-1556页

作者： Miao Xie Xiao-Rong Wang Zhan-Hua Wang he-sheng Xia State Key Laboratory of Polymer Materials Engineering Polymer Research InstituteSichuan University School of Petrochemical Engineering Liaoning Petrochemical University

Covalent adaptive networks (CANs) are capable of undergoing segment rearrangement after being heated, which endows the materials with excellent self-healing and reprocessing performance, providing an efficient solution to the environment pollution caused by the plastic wastes. The main challenge remains in developing CANs with both excellent reprocessing performance and creep-resistance property. In this study, a series of CANs containing dynamic covalent benzopyrazole-urea bonds were developed based on the addition reaction between benzopyrazole and isocyanate groups. DFT calculation confirmed that relatively low dissociation energy is obtained through undergoing a five-member ring transition state, confirming excellent dynamic property of the benzopyrazole-urea bonds. As verified by the FTIR results, this nice dynamic property can be well maintained after incorporating the benzopyrazole-urea bonds into polymer networks. Excellent self-healing and reprocessing performance is observed by the 3-ABP/PDMS elastomers owing to the dynamic benzopyrazole-urea bonds. Phase separation induced by the aggregation of the hard segments locked the benzopyrazole-urea bonds, which also makes the elastomers display excellent creep-resistance performance. This hard phase locking strategy provides an efficient approach to design CANs materials with both excellent reprocessing and creep-resistance performance.

关键词： Covalent adaptive networks Dynamic covalent bond Self-healing polymer

Alpine grassland degradation intensifies the burrowing behavior of small mammals:evidence for a negative feedback loop

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Integrative Zoology 2024年第2期19卷 240-252页

作者： Zaiwei WANG Jiawen YAN Amy MARTIN Dianne HBRUNTON Jiapeng QU Jin-sheng he Weihong JI Zhibiao NAN State Key Laboratory of herbage Improvement and Grassland Agro-Ecosystems College of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhouChina Manaaki Whenua-Landcare Research LincolnNew Zealand School of Natural Sciences Massey University(Albany Campus)AucklandNew Zealand Key Laboratory of Adaptation and Evolution of Plateau Biota Northwest Institute of Plateau BiologyChinese Academy of SciencesXiningChina Qinghai Haibei National Field Research Station of Alpine Grassland Ecosystem Northwest Institute of Plateau BiologyChinese Academy of SciencesXiningChina Institute of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking UniversityBeijingChina

Globally,grassland degradation is an acute ecological *** alpine grassland on the Tibetan Plateau,increased densities of various small mammals in degraded grassland are assumed to intensify the degradation process and these mammals are subject to lethal ***,whether the negative impact of small mammals is solely a result of population size or also a result of activity and behavior has not been *** this study,we use plateau pika as a model to compare population size,core area of colony,and the number of burrow entrances and latrines between lightly and severely degraded *** test whether the alleged contribution of pika to grassland degradation is a result of increased population size or increased burrowing activities of individuals in response to lower food *** found that grassland degradation resulted in lower plant species richness,plant height,and ***,the overall population size of pika was not significantly affected by location in lightly and severely degraded ***,pika core areas in severely grassland degradation were significantly larger and had significantly higher densities of burrows and *** study provides convincing evidence that habitat-induced changes in the behavior of small,burrowing mammals,such as pika,can exacerbate grassland *** finding has significant implications for managing small mammals and restoring degraded grassland ecosystems.

关键词： burrowing behavior grassland degradation plateau pika population size small mammals

Brain-inspired artificial intelligence research: A review

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Science China(Technological Sciences) 2024年第8期67卷 2282-2296页

作者： WANG GuoYin BAO HuaNan LIU Qun ZHOU TianGang WU Si HUANG TieJun YU ZhaoFei LU CeWu GONG YiHong ZHANG ZhaoXiang he sheng Chongqing Key Laboratory of Computational Intelligence Chongqing University of Posts and TelecommunicationsChongqing 400065China Key Laboratory of Cyberspace Big Data Intelligent Security Chongqing University of Posts and TelecommunicationsChongqing 400065China College of Computer and Information Science Chongqing Normal UniversityChongqing 401331China State Key Laboratory of Brain and Cognitive Science Institute of BiophysicsChinese Academy of SciencesBeijing 100101China School of Psychological and Cognitive Sciences Peking UniversityBeijing 100871China State Key Laboratory of Multimedia Information Processing School of Computer SciencePeking UniversityBeijing 100871China Department of Computer Science School of ElectronicsInformation and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Faculty of Electronic and Information Engineering Xi’an Jiaotong UniversityXi’an 710049China The Center for Research on Intelligent Perception and Computing Institute of AutomationChinese Academy of SciencesBeijing 100190China Institute of Biophysics Chinese Academy of SciencesBeijing 100101China

Artificial intelligence(AI) systems surpass certain human intelligence abilities in a statistical sense as a whole, but are not yet the true realization of these human intelligence abilities and behaviors. There are differences, and even contradictions, between the cognition and behavior of AI systems and humans. With the goal of achieving general AI, this study contains a review of the role of cognitive science in inspiring the development of the three mainstream academic branches of AI based on the three-layer framework proposed by David Marr, and the limitations of the current development of AI are explored and analyzed. The differences and inconsistencies between the cognition mechanisms of the human brain and the computation mechanisms of AI systems are analyzed. They are found to be the cause of the differences and contradictions between the cognition and behavior of AI systems and humans. Additionally, eight important research directions and their scientific issues that need to focus on braininspired AI research are proposed: highly imitated bionic information processing, a large-scale deep learning model that balances structure and function, multi-granularity joint problem solving bidirectionally driven by data and knowledge, AI models that simulate specific brain structures, a collaborative processing mechanism with the physical separation of perceptual processing and interpretive analysis, embodied intelligence that integrates the brain cognitive mechanism and AI computation mechanisms,intelligence simulation from individual intelligence to group intelligence(social intelligence), and AI-assisted brain cognitive intelligence.

关键词： artificial intelligence cognitive science brain science intelligence science large language model

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Sedimentary architecture of submarine channel-lobe systems under different seafloor topography:Insights from the Rovuma Basin offshore East Africa

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Petroleum Science 2024年第1期21卷 125-142页

作者： Mei Chen sheng-he Wu Rui-Feng Wang Jia-Jia Zhang Peng-Fei Xie Min Wang Xiao-Feng Wang Ji-Tao Yu Qi-Cong Xiong State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China College of Geosciences China University of Petroleum(Beijing)Beijing102249China Faculty of Geosciences University of BremenBremen28359Germany MARUM-Center for Marine and Environmental Sciences University of BremenBremen28359Germany Research institute of Petroleum Exploration and Development PetroChinaBeijing10083China School of Geosciences Yangtze UniversityWuhan 100083HubeiChina CNODC Mozambique Ltd. Beijing 100034China

Seafloor topography plays an important role in the evolution of submarine ***,it is still not so clear how the shape of slope affects the three-dimensional(3-D)architecture of submarine *** this study,we analyze the effect of topography factors on different hierarchical lobe architectures that formed during Pliocene to Quaternary in the Rovuma Basin offshore East *** characterize the shape,size and growth pattern of different hierarchical lobe architectures using 3-D seismic *** find that the relief of the topographic slope determines the location of preferential deposition of lobe complexes and single *** the topography is irregular and presents topographic lows,lobe complexes first infill these *** lobes are deposited preferentially at positions with higher longitudinal(***-slope)slope *** the longitudinal slope becomes higher,the aspect ratio of the single lobes ***(***-slope)topography does not seem to have a strong influence on the shape of single lobe,but it seems to affect the overlap of single *** the lateral slope gradient is relatively high,the single lobes tend to have a larger overlap ***,as the average of lateral slope and longitudinal slope gets greater,the width/thickness ratio of the single lobe is smaller,*** tend to accumulate *** results demonstrate that the shape of slopes more comprehensively influences the 3-D architecture of lobes in natural deep-sea systems than previously other lobe deposits and analogue experiments,which helps us better understand the development and evolution of the distal parts of turbidite systems.

关键词： Submarine fan Seafloor topography Sedimentary architecture Slope system SW Indian ocean

Unraveling the hydrothermal history of the Xinshuijing Na-metasomatite uranium deposit in the Longshoushan metallogenic belt， Northwest China by coupled hydrothermal zircon U–Pb and albite Ar–Ar dating

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Journal of Earth Science 2024年

作者： JUN ZHONG MARK MIHALASKY MICheL CUNEY sheng he JUN-JIE LI National Key Laboratory of Uranium Resource Exploration-Mining and Nuclear Remote Sensing， Beijing Research Institute of Uranium Geology International Atomic Energy Agency (IAEA)， Nuclear Fuel Cycle and Materials Section， Division of Nuclear Fuel Cycle and Waste Technology， Vienna International Center Université de Lorraine， GéoRessources CNRS State Key Laboratory of Lithospheric Evolution (SKLLE)， Institute of Geology and Geophysics， Chinese Academy of Sciences

Na-metasomatite uranium deposits are an important type of large-tonnage low-grade uranium deposit. They are characterized by an intimate association between uranium minerals and albite， and by the common development of syn-ore hydrothermal zircons. Similar to other types of uranium deposits， constraining an accurate age of mineralization remains a challenge for the Na-metasomatite type ones. In this study， we present for the first time， an approach that combines age dating results from the syn-ore albites (40Ar-39Ar) and hydrothermal zircons （U-Pb） for a typical Na-metasomatite uranium deposit， the Xinshuijing deposit in the Longshoushan metallogenic belt of northwest China. The hydrothermal zircon U-Pb and albite40Ar-39Ar ages are consistent with each other （378-366 Ma; within error）， but also identical to the previously reported uraninite chemical U-Pb ages （approximately 370 Ma）. The coupled application of hydrothermal zircon U-Pb and albite40Ar-39Ar age dating is thus regarded as a robust approach for constraining the age of mineralization for Na-metasomatite uranium deposits. An age gap of approximately 70 m.y. between uranium mineralization （～ 370 Ma） and host granitoid emplacement （about 440 Ma） suggests no direct genetic linkage between the two. Further exploration in the surrounding metamorphic units is therefore suggested， rather than only focusing on the host granitoids， especially where intensive wallrock alteration and structural features are pervasive. The varied hydrothermal zircon δ18O isotope compositions are attributed to the significant fluid-wallrock interaction during the uranium mineralization， which is consistent with our previous fluid inclusion and geochemical studies. Our study highlights the importance of selecting appropriate isotopic dating methods， which is informed by detailed paragenetic and geochemical analysis of dateable minerals formed before or coeval to the main-stage uranium mineralization. Moreover， it is underlined that the e

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多晶材料散射模型及识别实验研究

物理学报 2024年第3期73卷 134-142页

作者：刘昱贺西平贺升平陕西师范大学物理学与信息技术学院陕西省超声重点实验室西安710119 泸州高新技术研究所泸州646000

超声波识别在国防、军事、航空航天、核设施等高科技领域具有重要的应用价值.利用超声波可以实现对个体金属材料的识别,但现有研究侧重于识别材料超声信号差异的算法,缺乏识别机理.本文以2A12铝合金为例,利用6个晶粒在尺寸、形状、排布... 详细信息

超声波识别在国防、军事、航空航天、核设施等高科技领域具有重要的应用价值.利用超声波可以实现对个体金属材料的识别,但现有研究侧重于识别材料超声信号差异的算法,缺乏识别机理.本文以2A12铝合金为例,利用6个晶粒在尺寸、形状、排布方向以及排列顺序不同时,建立了10个2A12铝合金微结构的初级模型,以此类比多晶金属材料的复杂微观结构.利用Comsol有限元软件仿真计算了金属材料不同微观结构中的超声波时域信号,并将回波信号中的的背向散射信号提取为超声指纹.定义了特征差异Q,量化了具有不同微结构的散射模型间的超声指纹的差异.结果表明,微观结构的细微变化也会导致超声信号出现差异,其中晶粒尺寸的变化对信号的影响更为显著.随后提出了超声识别算法,并对4块形状完全一致的2A12铝合金样品进行了识别实验.识别结果表明,利用超声指纹可以准确识别出目标样品,且各样品间的超声指纹有显著区别.最后对样品进行了扫描电子显微镜实验,所得电子显微镜图片显示了各样品真实微观结构的形貌与差异,证实了所建立的超声散射模型的有效性.

关键词：超声散射微观结构多晶材料超声识别有限元方法

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Coexistence of adeno-associated virus 2 with adenovirus 18 or herpesvirus may be associated with severe lingual papillomatosis in an immunocompromised individual

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Virologica Sinica 2024年第4期39卷 705-707页

作者： Jie-Mei Yu Ze-Yin Liang Yuan-Hui Fu Xiang-Lei Peng Yan-Peng Zheng Yu-Jun Dong Jin-sheng he College of Life Sciences and Bioengineering Beijing Jiaotong UniversityBeijing100044China Department of hematology Peking University First HospitalBeijing100034China

Dear Editor,Patients undergoing allogeneic hematopoietic stem cell transplantation(HSCT)often experience a significant reduction in immune function due to factors such as severe lymphopenia,immunosuppressive treatment,and the development of graft-versus-host disease,rendering them more susceptible to severe infections(Sahin et al.,2016).Traditional diagnostic approaches are limited in sensitivity,speed,and assay targets,thus failing short of meeting the diagnostic demands(Qu et al.,2022).However,next-generation sequencing(NGS)has greatly improved the accuracy and efficiency of diagnosing various diseases(Schuler et al.,2022),and has been widely utilized for pathogen detection in samples from HSCT patients(Armstrong et al.,2019;Peng et al.,2021).In this study,we employed viral metagenomics analysis using high-throughput sequencing on fecal and tissue samples from a patient with HSCT experiencing severe lingual papillomatosis.

关键词： al. papilloma rendering

汉字元素+坐具设计——基于汉字的创意设计启迪

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家具与室内装饰 2024年第2期31卷 42-44页

作者：何盛浙江大学浙江杭州310058

作品简介2014年,习总书记在十八届中央政治局第十三次集体学习时指出,“弘扬中华优秀传统文化,要处理好继承和创造性发展的关系,重点做好创造性转化和创新性发展。”习近平总书记的短短两句话中,包含了几个重要的概念。一是“中华文化... 详细信息

作品简介2014年,习总书记在十八届中央政治局第十三次集体学习时指出,“弘扬中华优秀传统文化,要处理好继承和创造性发展的关系,重点做好创造性转化和创新性发展。”习近平总书记的短短两句话中,包含了几个重要的概念。一是“中华文化”。这是一个国际化的概念,历史上,中国对世界的影响是巨大的,比如汉字,在古代,汉字曾是东亚地区的交流文字,20世纪前仍是日本、朝鲜半岛、越南等地官方书面规范文字,至今在一些国家中还在大量使用自行创制的汉字,深受汉文化的影响。比如曾经流行于欧洲的“中国风”和至今各国大量存在的“中国城”等。都体现着“中华文化”的概念,这是在全世界范围内的一种文化存在。

关键词：作品简介创意设计汉字元素中华文化集体学习坐具设计弘扬中华优秀传统文化朝鲜半岛

以苏联解体教训为镜鉴的铸牢中华民族凝聚力研究

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新疆大学学报（哲学社会科学版） 2024年第1期52卷 20-26页

作者：何金生广西师范大学马克思主义学院广西桂林541004

民族凝聚力究竟何以可能,是学术研究亟待深化的问题。总结我国建党一百年铸牢中华民族凝聚力的实践经验,以苏联解体教训为镜鉴,民族凝聚力问题绝非单纯的政治问题,而是多因素相互交集相互作用的结果。物质文明建设是铸牢中华民族多元一... 详细信息

民族凝聚力究竟何以可能,是学术研究亟待深化的问题。总结我国建党一百年铸牢中华民族凝聚力的实践经验,以苏联解体教训为镜鉴,民族凝聚力问题绝非单纯的政治问题,而是多因素相互交集相互作用的结果。物质文明建设是铸牢中华民族多元一体意识的物质基础,精神文明建设是铸牢中华民族共同体价值共识的思想支柱,政治文明建设是铸牢中华民族共同体稳定和谐意识的政治保障,社会文明建设是铸牢中华民族共同体由小康到大同社会意识的社会环境因素,生态文明建设是铸牢中华民族共同体生态意识的自然根基。中国共产党的全面领导是铸牢中华民族共同体意识,增强中华民族凝聚力,引领各族人民共同实现中华民族伟大复兴的根本保障。

关键词：建党百年中华民族民族凝聚力五种因素苏联解体