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Journal of Environmental Sciences 2024年第3期137卷 347-357页

作者： Tengda Shi Ruijing li Jie Fu Chao Hou Hui gao Guanjie Cheng Haibo Zhang Shuaichen jin liang Kong Guangshui Na College of Marine Technology and Environment Dalian Ocean UniversityDalian 116023China Laboratory for coastal marine eco-environment process and carbon sink of Hainan province/Yazhou Bay Innovation Institute Hainan Tropical Ocean UniversitySanya 572022China National Marine Environmental Monitoring Center Dalian 116023China College of Marine Ecology and Environment Shanghai Ocean UniversityShanghai 201306China NCS Testing Technology Co. Ltd.Beijing 10081China

Eleven organophosphate esters(OPEs)in the air and seawater were investigated from the northwestern Pacific Ocean to the Southern Ocean during the 2018 Chinese 34th Antarctic Scientific *** concentration of total OPEs ranged from 164.82 to 3501.79 pg/m~3in air and from 4.54 to 70.09 ng/L in *** halogenated OPEs,tri(chloropropyl)phosphate(TCPP)and tri(2-chloroethyl)phosphate(TCEP),were generally more abundant than the non-halogenated OPEs.A levelⅢfugacity model was developed to simulate the transfer and fate of seven OPEs in the air and seawater regions of the central Ross *** model results indicate that OPEs are transferred from the air to the seawater in the central Ross Sea in summer,during which the Ross Sea acts as a final OPE *** and wet deposition dominated the processes involving OPE transfer to *** OPE degradation process was also found to be more pervasive in the atmosphere than in the seawater *** findings highlights the importance of long-range transport of OPEs and their air–seawater interface behavior in the Antarctic.

关键词： Organophosphate esters(OPEs) Long-range transport Fugacity model Antarctic Fate

A ratiometric optical thermometer with dual-color emission based on Eu^(2+)-doped CsCu_(2)I_(3) microcrystals

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Journal of Rare Earths 2024年第8期42卷 1429-1436,I0001页

作者： Xiaorong li Ge gao Kaiyu Wang Zhaoqiong Chen Zejiang gao Qingyong Qin li Chen Bingsuo Zou State Key Laboratory of Featured Metal Materials and life-cycle Safety for Composite Structures School of Physical Science and TechnologyGuangxi UniversityNanning530004China School of Resources Environments and MaterialsGuangxi UniversityNanning530004China

With the increasing demand for non-co ntact fluorescence intensity ratio-based optical thermometry,novel phosphor materials with high-efficiency,dual-emitting centers,and differentiable temperature sensitivity are highly desired,In this wo rk,rare earth Eu^(2+) ions were incorporated Wnto CsCu_(2)I_(3) microcrystals by solidstate reaction,Under a single UV excitation,the as-synthesized samples exhibit two emissions:452 nm blue emission from the 5d→4f transition of Eu^(2+)and 582 nm yellow emission from self-trapped exciton e mission of CsCu_(2)I_(3).The photoluminescence quantum yield reaches to 50%,The dual-band emission of Eu^(2+)-doped CsCu_(2)I_(3) shows different temperature responses in the range of 260-360 *** on fluorescence intensity ratio technology,the maximum absolute sensitivity and re Iative sensitivity are 0.091 K^(-1)(at 360 K) and 2.60%/K(at 260 K),*** results suggest that Eu^(2+)-doped GsCu_(2)I_(3) could be a good candidate for highly sensitive optical thermometer.

关键词： CsCu_(2)I_(3) Eu^(2+)-doping Fluorescence intensity ratio Optical thermometer Rare earths

Variable Selection for Generalized linear Model with Highly Correlated Covariates

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Acta Mathematica Sinica,English Series 2024年第6期40卷 1458-1480页

作者： li li YUE Wei Tao WANG gao Rong li School of Statistics and Data Science Nanjing Audit UniversityNanjing 211815P.R.China School of Mathematics Statistics and MechanicsBeijing University of TechnologyBeijing 100124P.R.China School of Statistics Beijing Normal UniversityBeijing 100875P.R.China

The penalized variable selection methods are often used to select the relevant covariates and estimate the unknown regression coefficients simultaneously,but these existing methods may fail to be consistent for the setting with highly correlated *** this paper,the semi-standard partial covariance(SPAC)method with Lasso penalty is proposed to study the generalized linear model with highly correlated covariates,and the consistencies of the estimation and variable selection are shown in high-dimensional settings under some regularity *** simulation studies and an analysis of colon tumor dataset are carried out to show that the proposed method performs better in addressing highly correlated problem than the traditional penalized variable selection methods.

关键词： Generalized linear model highly correlated covariates Lasso penalty semi-standard partial covariance variable selection

Thermally modulated photoelectronic synaptic behavior in HfS2/VO2 heterostructure

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Rare Metals 2024年第8期43卷 3798-3809页

作者： Le Wang lin Wang Xiao-Yun Ye Xiong-Hu Xu li-Yan Shang Ya-Wei li jin-Zhong Zhang liang-Qing Zhu Zhi-gao Hu Technical Center for Multifunctional Magneto-Optical Spectroscopy (Shanghai) Engineering Research Center of Nanophotonics & Advanced Instrument (Ministry of Education) Department of PhysicsSchool of Physics and Electronic ScienceEast China Normal University Collaborative Innovation Center of Extreme Optics Shanxi University

Neuromorphic computing is known for its efficient computational speed,low latency,and reduced power consumption,which is considered a pivotal technology to overcome the von Neumann *** synapses are an indispensable component of neuromorphic computational artificial neural *** guarantee effective and precise processing of optical signals,it must have a high responsivity,detectivity,and the ability to adapt to various ***,a synaptic transistor based on the HfS2/VO2heterojunction with a responsivity of8.6×10～3 A·W-1and a detectivity of 1.26×1014Jones at405 nm laser was ***,the typical synaptic behavior was successfully simulated,including postsynaptic currents（PSCs）,the transition from shortterm plasticity（STP） to long-term plasticity（LTP）.When VO2converts from the semiconductor state to the metal state,the HfS2/VO2heterojunction transforms into a Schottky heterojunction from a Type Ⅱ heterojunction with ***'s important,the heterojunction still exhibits excellent responsivity and detectivity,as well as stability of synaptic *** addition,the classical Pavlovian conditioning experiment is simulated under different laser intensity to study the brain's associative learning *** results demonstrate that the HfS2/VO2heterojunction synapse exhibits significant responsivity and detectivity and is adaptable to high-temperature environments,showing great potential for neuromorphic computational applic ations.

关键词： HfS 2 VO 2 Phase transition Photoelectric synapse Heterojunction

Spatiotemporal pattern of climate change in the China-Myanmar Economic Corridor from 1901 to 2018

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Journal of Mountain Science 2024年第1期21卷 131-145页

作者： YANG Xiaoliu li Yungang gao Lu Institute of Geography Fujian Normal UniversityFuzhou 350117China School of Geographical Sciences Fujian Normal UniversityFuzhou 350117China Institute of International Rivers and Eco-Security Yunnan UniversityKunming 650500China Fujian Provincial Engineering Research Center for Monitoring and Accessing Terrestrial Disasters Fujian Normal UniversityFuzhou 350117China Key Laboratory for Humid Subtropical Eco-geographical Processes of the Ministry of Education Fujian Normal UniversityFuzhou 350117China

The China-Myanmar Economic Corridor(CMEC) is an important part of China's Belt and Road Initiative and an important area for global ecology and biodiversity. In this study, the annual and seasonal spatiotemporal patterns of temperature and precipitation in the CMEC over the past century were investigated using linear tendency estimation, the Mann-Kendall mutation test, the T-test, and wavelet analysis based on the monthly mean climatic data from 1901 to 2018 released by the Climatic Research Unit(CRU) of the University of East Anglia, UK. The results show that the CMEC demonstrated a trend of warming and drying over the past 100 years, and the rate of change in Myanmar was stronger than that in Yunnan Province of China. The warming rate was 0.039 ℃/10a. Precipitation decreased at a rate of -6.1 mm/10a. From the perspective of spatial distribution, temperature was high in the central and southern, low in the north of the CMEC, and the high-temperature centers were mainly distributed in the southern plain and river valley. Precipitation decreased from west to east and from south to north of the CMEC. From the perspective of the rate of change, warming was stronger in central and northern CMEC than in southern and northeastern CMEC. The rate of precipitation decline was stronger in the central and western regions than in the eastern region. This study provides a scientific reference for the CMEC to address climate change and ensure sustainable social and economic development and ecological security.

关键词： China-Myanmar Economic Corridor CRU Air temperature Precipitation Spatiotemporal pattern

A weak but inert hindered urethane bond for high-performance dynamic polyurethane polymers

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Chinese Chemical Letters 2024年第5期35卷 238-243页

作者： Fangzhou Wang Wentong gao Chenghui li State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringCollaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210023China School of Materials Science and Engineering Nanjing Institute of TechnologyNanjing 211167China

Covalent adaptable networks(CANs),which share the properties of both thermosets and thermoplastics at the same time,are desirable for many *** bulky substituents is a feasible way to design dynamic covalent bonds for constructing CANs,as evidenced by the successful implementation in CANs based on hindered urea bonds(HUBs).However,the dynamicity induced by introducing bulky substituents always come with low bond energy,resulting in low mechanical strength and poor stability of the ***,we designed a novel hindered urethane bond,which is weak in thermodynamic(K_(eq)=1701.23 L/mol at 25℃)and inert in kinetic at low temperature,but stable in thermodynamic(K_(eq)=1.54×10^(4) L/mol at 100℃)and active in kinetic at high temperature(k_(-1)=0.105 h^(-1) at 80℃ and 0.315 h^(-1) at 120℃).As a result,the polyurethane based on it exhibits high mechanical properties(with Youngs’modulus of 1011±29MPa and flexible modulus reached 1833±50MPa)and excellent reversibility(can be reprocessed at 60℃ under 100 kPa in 30 min and completely healed at 40℃ in 10 min).Moreover,unlike to many CANs based on hindered urea bonds,our dynamic polyurethanes are highly stable in humid environment or even water solutions due to the slow hydrolysis *** highperformance dynamic polyurethane polymers are attractive for many applications.

关键词： Covalent adaptable networks Urethane bond Kinetics Thermodynamics

Influencing Factors of Healthy Aging Risk Assessed Using Biomarkers:A life Course Perspective

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China CDC weekly 2024年第11期6卷 219-224,I0014-I0017页

作者： Cedric Zhang Bo Lua Yajie gao jinming li Xingqi Cao Xinwei Lyu Yinuo Tu Shuyi jin Zuyun liu Center for Clinical Big Data and Analytics of the Second Affiliated Hospital and Department of Big Data in Health Science School of Public Healththe Key Laboratory of Intelligent Preventive Medicine of Zhejiang ProvinceZhejiang University School of MedicineHangzhou CityZhejiang ProvinceChina Institute of Epidemiology and Health Care University College LondonLondonUK College of Chemical and Biological Engineering Zhejiang UniversityHangzhou CityZhejiang ProvinceChina

Assessing individual risks of healthy aging using biomarkers and identifying associated factors have become important areas of *** this study,we conducted a literature review of relevant publications between 2018 and 2023 in both Chinese and English *** studies have predominantly used single biomarkers,such as C-reactive protein,or focused on specific life course stages and factors such as socioeconomic status,mental health,educational levels,and unhealthy *** summarizing the progress in this field,our study provides valuable insights and future directions for promoting healthy aging from a life course perspective.

关键词： such insight directions

Mn-modified nitrogen-doped Pt-based electrocatalyst for efficient oxygen reduction in aluminum-air batteries

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Nano Research 2024年第8期17卷 7126-7135页

作者： li gao Yang Song Xuebing Xu Chang li Chaoquan Hu State Key Laboratory of Mesoscience and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Zhongke Nanjing Institute of Green Manufacturing Industry Nanjing 211135China

In this study,a Mn-modified Pt-based catalyst loaded on nitrogen-doped Ketjen black(Mn-Pt/NKB)is prepared using a simple ethylene glycol reduction *** size of Pt nanoparticles(NPs)is effectively controlled by doping with Mn and *** the smallest average particle size of 1.7 nm,Mn-Pt/NKB demonstrates half-wave potentials of 0.890 and 0.688 V in the alkaline and neutral electrolytes,respectively,which are superior to those of commercial platinum on activated carbon(Pt/C).When applied as an air cathode in aluminum-air battery,it exhibits ultra-high power densities of 190(alkaline)and 26.2 mW·cm^(−2)(neutral).Moreover,the voltage remains stable after 5 h of *** practical application performance of the Mn-Pt/NKB catalyst in an aluminum-air battery is better than that of commercial Pt/***,the oxygen reduction reaction(ORR)mechanism on surfaces with different particle sizes is analyzed using density functional *** cracking is the major pathway on the surface of the small particles with lower energy consumption of 0.5 eV,while water molecule cleavage is the major pathway on the surface of the large particles with higher energy consumption of 0.97 *** lower energy consumption of the oxygen cracking pathway further confirms the ORR mechanism for higher activity on small-sized *** study provides a direction for the rational design of Pt-based catalysts for ORR and sheds light on the commercial development of aluminum-air batteries.

关键词： oxygen reduction reaction precious metal catalysts aluminum-air battery density functional theory(DFT)calculations reaction pathway

Flow Field Simulation and Parameter Analysis of Hydraulic Unbalanced Bionic Self-recovery Actuator for Rotary Equipment

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Journal of Bionic Engineering 2024年第1期21卷 325-343页

作者： Wei li Xin Pan Dehong Ge jinji gao Key Laboratory of Engine Health Monitoring-Control and Networking of Ministry of Education Beijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of High-End Mechanical Equipment Health Monitoring and Self-Recovery Beijing University of Chemical TechnologyBeijing 100029China

The rotor is the most important component of rotating machinery,and the vibration produced by its mass unbalance has a serious influence on the secure and steady operation of the machine,so an effective online suppression technology is urgently needed.A new hydraulic unbalanced bionic self-recovery system is introduced,imitating the way of manually repairing faulty *** accomplish the effect of actuator mass redistribution,the technology employs pressurized air to drive the quantitative transfer of liquid in the reservoir cavity at opposite *** can complete the online adjustment of the equipment's balancing state and suppress the unbalanced vibration of equipment in real time,which gives the equipment the ability to maintain an autonomous health state and improve equipment *** composition and working principle of the system are introduced in detail,and the key performance parameters,such as the minimum running speed and the balancing liquid transfer speed,are analyzed *** fluid-solid coupling model of the actuator was established,and the two-phase flow from inside the hydraulic unbalanced bionic self-recovery actuator was simulated under multiple working conditions and the performance parameters were quantitatively analyzed.A balancing simulation test bed was built,and its effectiveness was verified by performance parameter tests and unbalanced bionic self-recovery *** experimental results show that the mass distribution adjustment of the balancing disk can be achieved using different viscosity balancing liquid,and the response of liquid viscosity 10 cSt is faster than that of liquid viscosity 100 cSt in the process of balancing liquid transfer,and the time is reduced by more than 75%;the system can reduce the simulated rotor amplitude from 18.3μm to 10.6μm online in real time,which provides technical support for the subsequent development of a new generation of bionic intelligent equipment.

关键词： Engineering self-recovery-Bionics Simulation analysis Self-recovery regulation

Optimization study of spherical tuyere based on BP neural network and new evaluation index

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Building Simulation 2024年第2期17卷 223-234页

作者： Mengchao liu Ran gao Yi Wang Angui li School of Building Services Science and Engineering Xi’an University of Architecture and TechnologyXi’an710055China

The energy consumption of heating,ventilation,and air conditioning(HVAC)systems holds a significant position in building energy usage,accounting for about 65%of the total energy ***,with the advancement of building automation,the energy consumption of ventilation systems continues to *** study focuses on improving the performance of spherical tuyeres in HVAC *** primarily utilizes neural networks and multi-island genetic algorithms(MIGA)for multi-parameter *** employing methods such as structural parameterization,accurate and fast computational fluid dynamics(CFD)simulations,a minimized sample space,and a rational optimization strategy,the time cycle of the optimization process is ***,a new comprehensive evaluation index is proposed in this research to describe the performance of spherical tuyeres,which can be used to more accurately assess spherical tuyeres with different *** results show that by establishing a neural network prediction model and combining it with the multi-island genetic algorithm,a novel spherical tuyere design was successfully *** optimized novel spherical tuyeres achieved a 27.05%reduction in the spherical tuyeres effective index(STEI)compared to the traditional spherical ***,the resistance decreased by 15.68%,and the jet length increased by 7.57%.The experimental results demonstrate that our proposed optimization method exhibits high accuracy,good generalization capability,and excellent agreement at different Reynolds numbers.

关键词： spherical tuyeres STEI CFD ventilation