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Mobility and dynamic erosion process of granular flow:insights from numerical investigation using material point method

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Journal of Mountain Science 2024年第8期21卷 2713-2738页

作者： Yu Fangwei su Lijun LI Xinpo ZHAO Yu Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610299China university of Chinese Academy of Sciences Beijing 100049China China-Pakistan Joint Research Center on Earth Sciences Islamabad 45320Pakistan Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of SciencesBeijing 100101China College of Civil Engineering and Architecture Zhejiang UniversityHangzhou 310058China MOE Key Laboratory of Soft Soil and Geoenvironmental Engineering Zhejiang UniversityHangzhou 310058China

In order to understand the dynamics of granular flow on an erodible base soil,in this paper,a series of material point method-based granular column collapse tests were conducted to investigate numerically the mobility and dynamic erosion process of granular flow subjected to the complex settings,i.e.,the aspect ratio,granular mass,friction and dilatancy resistance,gravity and presence of water.A set of power scaling laws were proposed to describe the final deposit characteristics of granular flow by the relations of the normalized run-out distance and the normalized final height of granular flow against the aspect ratio,being greatly affected by the complex geological settings,e.g.,granular mass,the friction and dilatancy resistance of granular soil,and presence of water in granular *** index of the coefficient of friction of granular soil was defined as a ratio of the target coefficient of friction over the initial coefficient of friction to quantify the scaling extent of friction change(i.e.,friction strengthening or weakening).There is a characteristic aspect ratio of granular column corresponding to the maximum mobility of granular flow with the minimum index of the apparent coefficient of *** index of the repose coefficient of friction of granular flow decreased gradually with the increase in aspect ratio because higher potential energy of granular column at a larger aspect ratio causes a larger kinetic energy of granular soil to weaken the friction of granular soil as a kind of velocity-related friction *** increase in granular mass reduces gradually the indexes of the apparent and repose coefficients of friction of granular soil to enhance the mobility of granular *** mobility of granular flow increases gradually with the decrease in friction angle or increase in dilatancy angle of granular ***,the increase of gravity accelerates granular flow but showing the same final deposit profile without any dependence on ***

关键词： Column collapse Granular flow Granular soil Material point method Mobility Numerical tests

Multiple-quantum-coherence dynamics of spin-1 Bose–Einstein condensate during quantum phase transitions

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Communications in Theoretical Physics 2024年第1期76卷 105-110页

作者： Fulin Deng Peng Xu su Yi Wenxian Zhang Key Laboratory of Artificial Micro-and Nano-structures of Ministry of Education School of Physics and TechnologyWuhan UniversityWuhanHubei 430072China School of Physics Zhengzhou UniversityZhengzhou 450001China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China CAS Center for Excellence in Topological Quantum Computation&School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Wuhan Institute of Quantum Technology WuhanHubei 430206China

Multiple quantum coherences are often employed to describe quantum many-body dynamics in nuclear spin systems and recently,to characterize quantum phase transitions in trapped *** we investigate the multiple-quantum-coherence dynamics of a spin-1 Bose–Einstein *** adjusting the quadratic Zeeman shift,the condensate exhibits three quantum *** numerical results show that the spectrum of multiple quantum coherence does indeed catch the quantum critical *** importantly,with only a few low-order multiple quantum coherences,the spin-1 condensate exhibits rich signals of the many-body dynamics,beyond conventional *** experimental implementation of such multiple quantum coherence protocol is also discussed.

关键词： Bose-Einstein condensate spin-mixing dynamics quantum phase transitions multiple-quantum-coherences quantum entanglement

Redundant Data Detection and Deletion to Meet Privacy Protection Requirements in Blockchain-Based Edge Computing Environment

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China Communications 2024年第3期21卷 149-159页

作者： Zhang Lejun Peng Minghui su Shen Wang Weizheng Jin Zilong su Yansen Chen Huiling Guo Ran Sergey Gataullin Cyberspace Institute Advanced Technology Guangzhou UniversityGuangzhou 510006China College of Information Engineering Yangzhou UniversityYangzhou 225127China School Math&Computer Science Quanzhou Normal UniversityQuanzhou 362000China Computer Science Department City University of Hong KongHong Kong 999077China School of Computer and Software Nanjing University of Information Science and TechnologyNanjing 21004China Key Laboratory of Intelligent Computing and Signal Processing of Ministry of Education School of Computer Science and TechnologyAnhui UniversityHefei 230601China Department of Computer Science and Artificial Intelligence Wenzhou UniversityWenzhou 325035China Guangzhou university Library Guangzhou UniversityGuangzhou 510006China Central Economic and Mathematics Institute Russian Academy of Sciences MIREA-Russian Technological university Moscow RegionRussia

With the rapid development of information technology,IoT devices play a huge role in physiological health data *** exponential growth of medical data requires us to reasonably allocate storage space for cloud servers and edge *** storage capacity of edge nodes close to users is *** should store hotspot data in edge nodes as much as possible,so as to ensure response timeliness and access hit rate;However,the current scheme cannot guarantee that every sub-message in a complete data stored by the edge node meets the requirements of hot data;How to complete the detection and deletion of redundant data in edge nodes under the premise of protecting user privacy and data dynamic integrity has become a challenging *** paper proposes a redundant data detection method that meets the privacy protection *** scanning the cipher text,it is determined whether each sub-message of the data in the edge node meets the requirements of the hot *** has the same effect as zero-knowledge proof,and it will not reveal the privacy of *** addition,for redundant sub-data that does not meet the requirements of hot data,our paper proposes a redundant data deletion scheme that meets the dynamic integrity of the *** use Content Extraction Signature(CES)to generate the remaining hot data signature after the redundant data is *** feasibility of the scheme is proved through safety analysis and efficiency analysis.

关键词： blockchain data integrity edge computing privacy protection redundant data

Sources, enrichment mechanisms, and resource effects of rare metal elements-enriched geothermal springs in Xizang, China

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Science China Earth Sciences 2024年第11期67卷 3476-3499页

作者： Fei XuE Hongbing TAN Xiying ZHANG Jinbao su School of Earth Sciences and Engineering Hohai University Qinghai Provincial Key Laboratory of Geology and Environment of Salt Lakes Qinghai Institute of Salt Lakes Chinese Academy of Sciences School of Oceanology Hohai University

Rare metals such as lithium(Li), rubidium(Rb), and cesium(Cs) are strategically crucial mineral resources for the development of emerging industries in China. Ensuring a stable long-term supply of these resources is essential. The geothermal systems in Xizang, China are well-developed, with a wide distribution of various types. Most high-temperature geothermal systems in Xizang are exceptionally enriched in rare metal elements(RMEs) and have the potential to become a new source of rare metals to secure China's strategic mineral resource supply in the future. A close relationship also exists between the geothermal system and the special salt lake resources on the Tibetan Plateau. Geothermal springs thus play a key role in the migration and enrichment of RMEs from deep to shallow parts of the crust, in the transition between endogenous and exogenous mineralization, and source-to-sink processes. However, the mechanisms of element enrichment and evolution in these springs have not been systematically discussed, and many theoretical issues remain to be investigated. Based on summarizing and analyzing previous research, this study employs hydrochemical and isotopic geochemistry methods to investigate typical geothermal springs across Xizang and explore the anomalous enrichment mechanism of RMEs, and the resource effects of geothermal springs. Comprehensive analysis shows that the total dissolved solids(TDS) and hydrochemical types of geothermal springs are similar to those of major geothermal fields worldwide, but the Tibetan springs are abnormally rich in Li(averaging5.48 mg/L), Rb(averaging 0.75 mg/L), and Cs(averaging 3.58 mg/L), which are hundreds to thousands of times more concentrated than natural waters. The distribution of these enriched geothermal springs is controlled by the Yarlung Zangbo suture zone and the extended N-S trending rifts, especially in the intersection zone of the two, where the geothermal springs are the most enriched. Based on the spatial distr

关键词： Geothermal springs Rare metal elements Enrichment mechanisms Salt lakes Tibetan Plateau

Impact of climate change on food security in the Central Asian countries

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Science China Earth Sciences 2024年第1期67卷 268-280页

作者： Fang su Yu LIu Lvfan CHEN Rustam OROZBAEV Liangcheng TAN School of Economics and Management Northwest UniversityXi’an 710127China School of Economics and Management Shaanxi University of Science and TechnologyXi’an 710021China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China Institute of Geology National Academy of Sciences of Kyrgyz RepublicBishkek 720040Kyrgyzstan Institute of Global Environmental Change Xi’an Jiaotong UniversityXi’an 710049China

The current and potential impacts of global warming have generated widespread concerns about food security among all sectors of *** Asian countries located deep in the interior of Asia with fragile ecological environments and lower agricultural technology are particularly more prone to severe threats from climate *** on panel data acquired in five Central Asian countries from 1990 to 2019,a C-D-C model was developed to study how climate change affects food security in the region and to predict future *** study found that the level of food security has generally increased for these five Central Asian countries over the past 30 years,with Kazakhstan and Tajikistan having the highest and lowest food security levels,*** average annual temperature and precipitation exhibit an inverted u-shaped relationship with the region’s food security,with the most positive effect on the food security of *** high and low temperatures have significantly affected food security in the studied region,with Turkmenistan experiencing the most significant negative *** number of frost days had no significant effect on food *** analysis of future climate showed that the temperature and precipitation in Central Asia will continue to increase from 2030 to 2090,which will negatively impact the food security of these *** is recommended that the Central Asian countries enhance their understanding of climate risks,strengthen scientific climate research,and develop multiple adaptation strategies in ***,they are encouraged to consolidate international cooperation,reducing greenhouse gas emissions effectively and maintaining the ability to ensure food security.

关键词： Global warming Extreme climate Food security Future forecasts Five Central Asian countries

Nanomedicine-mediated immunogenic cell death and its combination with immune checkpoint blockade therapy

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Science China(Technological Sciences) 2024年第8期67卷 2350-2362页

作者： CHEN JunBin ZHANG YuXi su Miao ZHu YueQiang YANG XianZhu School of Biomedical Sciences and Engineering South China University of TechnologyGuangzhou International CampusGuangzhou 511442China National Engineering Research Center for Tissue Restoration and Reconstruction Guangdong Provincial Key Laboratory of Biomedical EngineeringKey Laboratory of Biomedical Materials and Engineering of the Ministry of EducationSouth China University of TechnologyGuangzhou 510006China

Cancer immunotherapies, which train the natural immune system to specifically kill tumor cells while sparing the healthy cells,have helped revolutionize cancer treatments and demonstrated promising clinical therapeutic benefits for decades. However, the therapeutic outcome of immunotherapies, even for the most successful immune checkpoint blockade(ICB) therapy, remains unsatisfactory in the clinical practice, mainly due to the low immunogenicity of solid tumors and its immunosuppressive tumor microenvironment(TME). Notably, several cancer treatment modalities, including chemotherapy, radiotherapy, and phototherapy, have been revealed to evoke tumor immunogenicity and reverse immunosuppressive TME via inducing immunogenic cell death(ICD) of tumor cells, which synergistically sensitized tumors to ICB therapy. Nanomedicines have been extensively applied to augment ICD-inducing treatment modalities and potentiate ICB therapeutic efficacy therapy due to the opportune convergence of immunotherapy and nanotechnology. Here, we discuss the recent advances in nanomedicine-mediated ICD and its combination with ICB therapy.

关键词： cancer immunotherapy nanomedicine immunogenic cell death immune checkpoint blockade

Flexible, thermal processable, self-healing, and fully bio-based starch plastics by constructing dynamic imine network

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Green Energy & Environment 2024年第10期9卷 1610-1618页

作者： Xiaoqian Zhang Haishan Zhang Guowen Zhou Zhiping su Xiaohui Wang State Key Laboratory of Pulp and Paper Engineering South China University of Technology

The serious environmental threat caused by petroleum-based plastics has spurred more researches in developing substitutes from renewable *** is desirable for fabricating bioplastic due to its abundance and renewable ***,limitations such as brittleness,hydrophilicity,and thermal properties restrict its widespread *** overcome these issues,covalent adaptable network was constructed to fabricate a fully bio-based starch plastic with multiple advantages via Schiff base *** strategy endowed starch plastic with excellent thermal processability,as evidenced by a low glass transition temperature （Tg=20.15℃）.Through introducing Priamine with long carbon chains,the starch plastic demonstrated superior flexibility （elongation at break=45.2%） and waterproof capability （water contact angle=109.2°）.Besides,it possessed a good thermal stability and self-adaptability,as well as solvent resistance and chemical *** work provides a promising method to fabricate fully bio-based plastics as alternative to petroleum-based plastics.

关键词： Bioplastic Covalent adaptable networks Schiff base chemistry Thermal processability Self-healing

Theoretical design of polyazole based ligands for the separation of Am(Ⅲ)/Eu(Ⅲ)

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Chinese Chemical Letters 2024年第8期35卷 406-412页

作者： Lingling su Qunyan Wu Congzhi Wang Jianhui Lan Weiqun Shi School of Nuclear Science and Technology University of South ChinaHengyang 421001China Laboratory of Nuclear Energy Chemistry Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China

The extraction of radioactive minor actinides(An(Ⅲ))from lanthanides(Ln(Ⅲ))is an extremely impor-tant step in nuclear waste *** ligands with high-performance actinide-selectivity re-mains an essential *** works have reported that some polyazole based ligands exhibit good An(Ⅲ)/Ln(Ⅲ)separation ***,we first evaluated the effects of different polyazole side chains on the Am(Ⅲ)/Eu(Ⅲ)selectivity by exploring three pyridine-derived polyazole ligands L^(1),L^(2)and L^(3)with 1,2,4-triazole,1,2,3-triazole,and pyrazole side chains,respectively,using scalar relativistic theoretical *** coordination structures,bonding properties and thermodynamic behaviors of AmL(NO_(3))_(3)and EuL(NO_(3))_(3)complexes were investigated,which clarifies that the side chains do affect the electronic structure of ligand and its selectivity for Am(Ⅲ)/Eu(Ⅲ)***,L^(1)with 1,2,4-triazole side chains exhibited the highest selectivity for Am(Ⅲ)over Eu(Ⅲ)while the lowest complexation ability for metal ions among the three pyridine-derived polyazole ***,we designed a new ligand L^(4)con-taining 1,2,4-triazole side chains and a preorganized phenanthroline ***,such a new ligand was verified to show stronger complexation ability and higher selectivity for Am(Ⅲ)/Eu(Ⅲ)ions than L^(1).This work clarifies the complexation nature of polyazole based ligands with Am(Ⅲ)/Eu(Ⅲ)ions and provides design strategies for highly efficient polyazole based ligands for An(Ⅲ)/Ln(Ⅲ)separation.

关键词： Solvent extraction Am(Ⅲ)/Eu(Ⅲ)separation Polyazole based ligands Design strategy Density functional theory

Biodegradation of Crystalline Chitin:A Review of Recent Advancement,Challenges,and Future Study Directions

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Journal of Ocean university of China 2024年第5期23卷 1319-1328页

作者： SONG Jianlin su Haipeng suN Jianan MAO Xiangzhao Sanya Institute of Oceanography Ocean University of ChinaSanya 572000China State Key Laboratory of Marine Food Processing and Safety Control College of Food Science and EngineeringOcean University of ChinaQingdao 266404China Qingdao Key Laboratory of Food Biotechnology Qingdao 266404China Key Laboratory of Biological Processing of Aquatic Products China National Light IndustryQingdao 266404China Laboratory for Marine Drugs and Bioproducts of Laoshan Laboratory Qingdao 266237China

Chitin is the second most abundant renewable polysaccharide on *** degradation of chitin into soluble and bioactive N-acetyl chitooligosaccharides(NCOSs)and N-acetyl-D-glucosamine(GlcNAc)has emerged as a pivotal step in the efficient and sustainable utilization of chitin ***,because of its dense structure,high crystallinity,and poor solubility,chitin typically needs pretreatment via chemical,physical,and other methods before enzymatic conversion to enhance the accessibility between substrates and enzyme ***,there has been considerable interest in exploring the direct biological degradation of crystalline chitin as a cost-effective and environment-friendly *** review endeavors to present several biological methods for the direct degradation of *** primarily focused on the importance of chitinase containing chitin-binding domain(CBD).Additionally,various modification strategies for increasing the degradation efficiency of crystalline chitin were ***,the review systematically elucidated critical components of multi-enzyme catalytic systems,highlighting their potential for chitin ***,the application of microorganisms in the degradation of crystalline chitin was also *** insights in this review contribute to the explorations and investigations of enzymatic and microbial approaches for the direct degradation of crystalline chitin,thereby fostering advancements in biomass conversion.

关键词： crystalline chitin chitinase biological degradation engineering microorganisms