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Chinese Journal of Polymer Science 2021年第6期39卷 702-708,I0006页

作者： Peng Zhou xuan-geng dai Jie Kong Jun Ling Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi'an 710072China

The synthesis of block copolymers of poly(tetrahydrofuran)-b-poly(α-amino acid)(PTHF-b-PAA)is challenging since it is difficult to combine the two blocks produced via different/conflicting ring-opening polymerization(ROP)*** this contribution,the cationic ROP of THF is catalyzed by rare-earth triflate[RE(OTf)3]and terminated by 2-(t-butyloxycarbonyl-amino)ethanol(BAE).After the deprotection of t-butyloxycarbonyl(Boc)group,the chain end of PTHF is quantitatively changed to amino group which thereafter initiates the nucleophilic ROP ofα-amino acid N-thiocarboxyanhydrides(NTAs).Both polymerizations are well controlled,generating PTHF and PAA segments with designable molecular weights(MWs).PTHF-b-polylysine(PTHF-b-PLys)and PTHF-b-polysarcosine(PTHF-b-PSar)are obtained with MWs between 8.6 and 28.7 kg/*** above amphiphilic diblock copolymers form micelles in ***40-b-PSar32 acts as a surfactant to stabilize oil-in-water *** segments of PTHF-b-PAA are biocompatible and promising in the biomedical application.

关键词： anhydride polymerization carbonyl

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

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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)

A Simplified Method for the Stress Analysis of Underground Transfer Structures Crossing Multiple Subway Tunnels

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2893-2915页

作者： Shen Yan Dajiang geng Ning dai Mingjian Long Zhicheng Bai College of Civil Engineering Tongji UniversityShanghai200092China China Construction 4th Engineering Bureau 6th Corp. Ltd.Shanghai201199China Department of Civil and Architecture Engineering Hubei Polytechnic UniversityHuangshi435003China

According to the design specifications,the construction of extended piles involves traversing the tunnel’s upper region and extending to the underlying rock *** address this challenge,a subterranean transfer structure spanning multiple subway tunnels was *** on the function of piles in the transfer structure as springs with axial and bending stiffness,and taking into account the force balance and deformation coordination conditions of beams and plates within the transfer structure,we established a simplified mechanical model that incorporates soil stratification by combining it with the Winkler elastic foundation beam *** resolved established simplifiedmechanicalmodel employed finite difference technology and the Newton-Simpsonmethod,elucidating the mechanical mechanism of the transfer *** research findings suggest that the load carried by the upper structural columns can be transferred to the pile foundation beneath the beams through the transfer structure,subsequently reaching the deep soil layer and ensuring minimal impact on adjacent *** established simplified analysis method can be used for stress analysis of the transfer structure,concurrently considering soil stratification,pile foundation behavior,and plate *** pile length,pile section size,and beam section size within the transfer structure should account for the characteristics of the upper load,ensuring an even distribution of the beam bending moment.

关键词： Crossing tunnels transfer structure force mechanism simplify analysis layered soil mass

Evolution of mechanical properties,localized corrosion resistance and microstructure of a high purity Al-Zn-Mg-Cu alloy during non-isothermal aging

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Journal of Central South University 2024年第6期31卷 1790-1807页

作者： dai xuan-xuan LI Yu-zhang LIU Sheng-dan YE Ling-ying BAO Chong-jun School of Materials Science and Engineering Central South UniversityChangsha 410083China Key Laboratory of Lightweight and High-strength Structural Materials Changsha 410083China Key Laboratory of Non-ferrous Metals Science and Engineering(Ministry of Education) Changsha 410083China Kunming Metallurgical Research Institute Co. Ltd.Kunming 650031China

The evolution of mechanical properties,localized corrosion resistance of a high purity Al-Zn-Mg-Cu alloy during non-isothermal aging(NIA)was investigated by hardness test,electrical conductivity test,tensile test,intergranular corrosion test,exfoliation corrosion test,slow strain rate tensile test and electrochemical test,and the mechanism has been discussed based on microstructure examination by optical microscopy,electron back scattered diffraction,scanning electron microscopy and scanning transmission electron *** NIA treatment includes a heating stage from 40℃to 180℃with a rate of 20℃/h and a cooling stage from 180℃to 40℃with a rate of 10℃/*** results show that the hardness and strength increase rapidly during the heating stage of NIA since the increasing temperature favors the nucleation and the growth of strengthening precipitates and promotes the transformation of Guinier-Preston(GPI)zones toη'*** the cooling stage,the sizes ofη'phase increase with a little change in the number density,leading to a further slight increase of the hardness and *** NIA proceeds,the corroded morphology in the alloy changes from a layering feature to a wavy feature,the maximum corrosion depth decreases,and the reason has been analyzed based on the microstructural and microchemical feature of precipitates at grain boundaries and subgrain boundaries.

关键词： Al-Zn-Mg-Cu alloy non-isothermal aging mechanical properties localized corrosion resistance microstructure

CPT: a pre-trained unbalanced transformer for both Chinese language understanding and generation

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Science China(Information Sciences) 2024年第5期67卷 43-55页

作者： Yunfan SHAO Zhichao geng Yitao LIU Junqi dai Hang YAN Fei YANG Zhe LI Hujun BAO Xipeng QIU School of Computer Science Fudan University Shanghai Key Laboratory of Intelligent Information Processing Fudan University Zhejiang Lab

In this paper, we take the advantage of previous pre-trained models(PTMs) and propose a novel Chinese pre-trained unbalanced transformer(CPT). Different from previous Chinese PTMs, CPT is designed to utilize the shared knowledge between natural language understanding(NLU) and natural language generation(NLG) to boost the performance. CPT consists of three parts: a shared encoder, an understanding decoder, and a generation decoder. Two specific decoders with a shared encoder are pretrained with masked language modeling(MLM) and denoising auto-encoding(DAE) tasks, *** the partially shared architecture and multi-task pre-training, CPT can(1) learn specific knowledge of both NLU or NLG tasks with two decoders and(2) be fine-tuned flexibly that fully exploits the potential of the model. Moreover, the unbalanced transformer saves the computational and storage cost, which makes CPT competitive and greatly accelerates the inference of text generation. Experimental results on a wide range of Chinese NLU and NLG tasks show the effectiveness of CPT.

关键词： pre-trained model transformer language model generation unified model

On the thermodynamics of plasticity during quasi-isentropic compression of metallic glass

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Matter and Radiation at Extremes 2024年第2期9卷 74-89页

作者： Kaiguo Chen Bo Chen Yinan Cui Yuying Yu Jidong Yu Huayun geng Dongdong Kang Jianhua Wu Yao Shen Jiayu dai College of Science National University of Defense TechnologyChangsha 410073People’s Republic of China Hunan Key Laboratory of Extreme Matter and Applications National University of Defense TechnologyChangsha 410073People’s Republic of China Applied Mechanics Laboratory Department of Engineering MechanicsSchool of AerospaceTsinghua UniversityBeijing 100084People’s Republic of China Institute of Fluid Physics China Academy of Engineering PhysicsMianyangPeople’s Republic of China Department of Material Science and Technology Shanghai Jiao Tong UniversityShanghaiPeople’s Republic of China

Entropy production in quasi-isentropic compression (QIC) is critically important for understanding the properties of materials under extremeconditions. However, the origin and accurate quantification of entropy in this situation remain long-standing challenges. In this work, a framework is established for the quantification of entropy production and partition, and their relation to microstructural change in QIC. Cu50Zr50is taken as a model material, and its compression is simulated by molecular dynamics. On the basis of atomistic simulation-informed physicalproperties and free energy, the thermodynamic path is recovered, and the entropy production and its relation to microstructural change aresuccessfully quantified by the proposed framework. Contrary to intuition, entropy production during QIC of metallic glasses is relativelyinsensitive to the strain rate ˙γ when ˙γ ranges from 7.5 × 10^(8) to 2 × 10^(9)/s, which are values reachable in QIC experiments, with a magnitudeof the order of 10^(−2)kB/atom per GPa. However, when ˙γ is extremely high (>2 × 10^(9)/s), a notable increase in entropy production rate with˙γ is observed. The Taylor–Quinney factor is found to vary with strain but not with strain rate in the simulated regime. It is demonstrated thatentropy production is dominated by the configurational part, compared with the vibrational part. In the rate-insensitive regime, the increase inconfigurational entropy exhibits a linear relation to the Shannon-entropic quantification of microstructural change, and a stretched exponential relation to the Taylor–Quinney factor. The quantification of entropy is expected to provide thermodynamic insights into the fundamentalrelation between microstructure evolution and plastic dissipation.

关键词： entropy metallic regime

A Skin-Inspired Self-Adaptive System for Temperature Control During Dynamic Wound Healing

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Nano-Micro Letters 2024年第8期16卷 211-224页

作者： Yaqi geng Guoyin Chen Ran Cao Hongmei dai Zexu Hu Senlong Yu Le Wang Liping Zhu Hengxue Xiang Meifang Zhu State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua University2999 North Renmin RoadShanghai 201620People’s Republic of China

The thermoregulating function of skin that is capable of maintaining body temperature within a thermostatic state is ***,patients suffering from skin damage are struggling with the surrounding scene and situational ***,we report an interactive self-regulation electronic system by mimicking the human thermos-reception *** skin-inspired self-adaptive system is composed of two highly sensitive thermistors(thermal-response composite materials),and a low-power temperature control unit(Laserinduced graphene array).The biomimetic skin can realize self-adjusting in the range of 35–42℃,which is around physiological *** thermoregulation system also contributed to skin barrier formation and wound *** wound models,the treatment group healed~10%more rapidly compared with the control group,and showed reduced inflammation,thus enhancing skin tissue *** skin-inspired self-adaptive system holds substantial promise for nextgeneration robotic and medical devices.

关键词： Thermo-reception Self-regulation Flexible electronic system Wound healing

Engineering high-performance dielectric chiral shells with enhanced chiral fields for sensitive chiral biosensor

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Rare Metals 2024年第3期43卷 1197-1206页

作者： Yi-Fan Wang Shan-Shan Huang Zhen-Dong dai Shi-Lin Xian xuan-Nan Wu Fu-Hua Gao Yi-Dong Hou College of Physics Sichuan UniversityChengdu610065China Graduate School of Sichuan University Sichuan UniversityChengdu610065China

Chiral metamaterials have been a topic of significant research interest in recent years due to their potential for various applications in nanophotonic devices and chiral ***,the intrinsic Ohmic loss in surface plasmonic resonance has limited their practical use,resulting in large light dissipation and weak chiroptical ***,we report on the development of high-performance dielectric chiral shells(DCS)through a two-step Si deposition process on a self-assembled microsphere *** form DCS sample completely oyercomes the cancelation effect originated from the disorder property of the micro-sphere monolayer in macroscale,and at a wavelength of approximately 710 nm,the measured optimal chiral signal(g-factor)and transmittance can reach up to 0.7 and 0.3,*** strong chiroptical effect comes from the asymmetric circular displacement currents(i.e.,magnetic modes)enabled by the specific shell *** chiral shell geometry,electromagnetic properties,sensor sensitivity of chiral molecules and figure of merit are systematically *** DCSs demonstrate highly sensitive detection of chiral biomolecules owing to their easily accessible geometry and enhanced uniform chiral field.

关键词： Dielectric chiral shells(DCS) Si deposition Magnetic resonance Highly sensitive sensor Chiral field

Molecular Mechanisms of Intracellular Delivery of Nanoparticles Monitored by an Enzyme‑Induced Proximity Labeling

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Nano-Micro Letters 2024年第6期16卷 14-37页

作者： Junji Ren Zibin Zhang Shuo geng Yuxi Cheng Huize Han Zhipu Fan Wenbing dai Hua Zhang Xueqing Wang Qiang Zhang Bing He Department of Pharmaceutics School of Pharmaceutical Sciences Peking University38 Xueyuan RdHaidian DistrictBeijing 100191People’s Republic of China

Achieving increasingly finely targeted drug delivery to organs,tissues,cells,and even to intracellular biomacromolecules is one of the core goals of *** the delivery destination is refined to cellular and subcellular targets,it is essential to explore the delivery of nanomedicines at the molecular ***,due to the lack of technical methods,the molecular mechanism of the intracellular delivery of nanomedicines remains unclear to ***,we develop an enzyme-induced proximity labeling technology in nanoparticles(nano-EPL)for the real-time monitoring of proteins that interact with intracellular ***(lactic-co-glycolic acid)nanoparticles coupled with horseradish peroxidase(HRP)were fabricated as a model(HRP(+)-PNPs)to evaluate the molecular mechanism of nano delivery in *** adding the labeling probe biotin-phenol and the catalytic substrate H_(2)O_(2)at different time points in cellular delivery,nano-EPL technology was validated for the real-time in situ labeling of proteins interacting with ***-EPL achieves the dynamic molecular profiling of 740 proteins to map the intracellular delivery of HRP(+)-PNPs in macrophages over *** on dynamic clustering analysis of these proteins,we further discovered that different organelles,including endosomes,lysosomes,the endoplasmic reticulum,and the Golgi apparatus,are involved in delivery with distinct participation *** importantly,the engagement of these organelles differentially affects the drug delivery efficiency,reflecting the spatial–temporal heterogeneity of nano delivery in *** summary,these findings highlight a significant methodological advance toward understanding the molecular mechanisms involved in the intracellular delivery of nanomedicines.

关键词： Enzyme-induced proximity labeling Intracellular delivery Nano-protein interaction Dynamic molecule profiling Macrophages

Grain Yield,Biomass Accumulation,and Leaf Photosynthetic Characteristics of Rice under Combined Salinity-Drought Stress

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Rice science 2024年第1期31卷 118-128,I0023页

作者： WEI Huanhe geng Xiaoyu ZHANG Xiang ZHU Wang ZHANG Xubin CHEN Yinglong HUO Zhongyang ZHOU Guisheng MENG Tianyao dai Qigen Jiangsu Key Laboratory of Crop Cultivation and Physiology/Jiangsu Key Laboratory of Crop Genetics and Physiology/Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops/Key Laboratory of Saline-Alkali Soil Reclamation and Utilization in Coastal Areas the Ministry of Agriculture and Rural Affairs of China/Research Institute of Rice Industrial Engineering TechnologyYangzhou UniversityYangzhou 225009China Institute of Agricultural Science and Technology Development/Joint International Research Laboratory of Agriculture and Agri-Product Safety the Ministry of Education of ChinaYangzhou UniversityYangzhou 225009China

Simultaneous stresses of salinity and drought often coincide during rice-growing seasons in saline lands,primarily due to insufficient water resources and inadequate irrigation ***,combined salinity-drought stress poses a major threat to rice *** this study,two salinity levels(NS,non-salinity;HS,high salinity)along with three drought treatments(CC,control condition;DJ,drought stress imposed at jointing;DH,drought stress imposed at heading)were performed to investigate their combined influences on leaf photosynthetic characteristics,biomass accumulation,and rice yield ***,drought,and their combination led to a shortened growth period from heading to maturity,resulting in a reduced overall growth *** yield was reduced under both salinity and drought stress,with a more substantial reduction under the combined salinity-drought *** combined stress imposed at heading caused greater yield losses in rice compared with the stress imposed at ***,the combined salinity-drought stress induced greater decreases in shoot biomass accumulation from heading to maturity,as well as in shoot biomass and nonstructural carbohydrate(NSC)content in the stem at heading and ***,it increased the harvest index and NSC remobilization *** and drought reduced the leaf area index and SPAD value of flag leaves and weakened the leaf photosynthetic characteristics as indicated by lower photosynthetic rates,transpiration rates,and stomatal *** reductions were more pronounced under the combined ***,drought,and especially their combination,decreased the activities of ascorbate peroxidase,catalase,and superoxide dismutase,while increasing the contents of malondialdehyde,hydrogen peroxide,and superoxide *** results indicated a more significant yield loss in rice when subjected to combined salinity-drought *** individual and combined stresses of salinity and dro

关键词： antioxidant defense system combined salinity-drought stress drought stress photosynthetic characteristics rice salinity stress