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Science China Chemistry 2024年第7期67卷 2300-2305页

作者： Zhiyan Chen Yan lv Wei Qin College of Physics Qingdao UniversityQingdao 266071China School of Physics State Key Laboratory of Crystal MaterialsShandong UniversityJinan 250100China Shandong Linuo Photovoltaic Hi-Tech Co. Ltd.Jinan 250100China

Multicomponent self-assembled chiral systems have attracted great attention due to their promising application in the area of spin-photonics and *** this work,through introducing an achiral third component into an achiral binary crystal,a chiral organic ternary crystal is fabricated,where both pronounced chiral-optical coupling and magnetic field dependence of chiral-optical activities are *** transformation of achiral structure into chiral structure generates a significant effect on the polarized state of light and the electron spin resonance ***,the coupling between circularly polarized photon and spin is observed in chiral ternary crystal with pronounced chiral orbit,where obvious magnetic field-transmissivity loop is ***,temperature could increase the magnitude of lattice parameters to lead to a larger helix radius to increase the chiral orbit ***,this work indicates that the further exploration of photon-chiral orbit-spin interactions in organic chiral ternary crystals is promising.

关键词： organic chiral ternary crystals chiral orbit chiral-optical activities magnetic field

Event-triggered sliding mode control of linear repetitive processes and its application in metal rolling process

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Science China(Information Sciences) 2024年第3期67卷 167-181页

作者： Xinyu lv Yugang NIU James LAM Key Laboratory of Smart Manufacturing in Energy Chemical Process (East China University of Science and Technology) Ministry of Education Department of Mechanical Engineering The University of Hong Kong

This paper investigates the design problem of a sliding mode controller for linear repetitive processes(LRPs) with a finite pass length on each pass. Under limited communication resources, an eventtriggered mechanism is implemented from the sensors to the controller, whose triggered sequence is consistent with the evolution direction of LRPs. To periodically orchestrate communication between the controller and actuator, a round-robin scheduling mechanism is established based on the pass length. A sliding function involving the state and pass profile is constructed, and the sliding mode controller is designed using triggered states and pass profile signals. Feasible controller gains are attained to ensure the stability of the resultant closed-loop system. Finally, the proposed strategy is implemented for a multi-roll metal rolling process.

关键词： event-triggered mechanism linear repetitive processes metal rolling process round-robin scheduling sliding mode control

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Numerical Study on Local Flow and Heat Transfer Characteristics of Supercritical CO_(2) in PCHE with Sinusoidal Channels

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Journal of Thermal Science 2024年第1期33卷 41-55页

作者： WENZhexi lv Yigao LI Qing WU Jinglin School of Energy Science and Engineering Central South UniversityChangsha 410083China

Local heat transfer and flow characteristics,which is crucial to the overall performance of supercritical CO_(2) recuperators,is rarely examined in details in reported *** this paper,the local heat transfer and flow characteristics of supercritical CO_(2) in sinusoidal channel printed circuit heat exchangers are numerically investigated under the working conditions of *** on the simplified physical model constituted by10 pitches,the variations of Re,heat flux,Nu,secondary flow and other relevant parameters along the flow direction are analyzed *** is further made between the high and low temperature recuperators(HTR and LTR).It's observed that the local heat transfer and flow characteristics vary greatly from the inlet to the outlet,especially in the *** of 127.5% and 61.7% can be observed on the cold side of the LTR for Re and heat transfer coefficient h, *** indicate that the temperature difference and heat transfer coefficient h should not be regarded as constant and the distribution of h should be carefully considered in the design of the *** complicated interactions among the varying thermophysical properties,buoyancy and the periodically changed centrifugal force are believed to be the key that shapes the flow ***,the changes of the wavy angle θ are found to have greater influence than the changes of mass flow rate in reshaping the flow field when θ>25°.Though gravity direction strongly affects the local heat transfer and flow characteristics,it's also found that the effects on the overall thermal-hydraulic performance are relatively *** the installation direction that yields a_y=g should better be avoided for the sinusoidal channel printed circuit heat exchanger.

关键词： printed circuit heat exchanger supercritical CO_(2) sinusoidal channel heat transfer recuperator

A Generalized MSST Algorithm for Counting Points of Elliptic Curves over F_(p)^(n)

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Journal of Systems Science & Complexity 2024年第4期37卷 1738-1754页

作者： LI Xiao lv Chang PAN Zhizhong Key Laboratory of Cyberspace Security Defense Institute of Information EngineeringChinese Academy of SciencesBeijing 100085China School of Cyber Security University of Chinese Academy of SciencesBeijing 100085China Huawei Technologies Co. Ltd.Shenzhen 518129China

Elliptic curve cryptography is an important part of nowaday's public key *** points of elliptic curves over finite fields is of great significance to the selection of safety *** present,there are many p-adic algorithms,such as SST algorithm,generalized AGM algorithm,Kedlaya algorithm,etc.,which can deal with the situation of finite fields of small *** this paper,the authors generalize the MSST algorithm of characteristic 2 to general fields of odd characteristic,and propose the generalized MSST *** generalized MSST algorithm is achieved by combining the advantages of the SST algorithm and the generalized AGM *** the time complexity of the multiplication of two n-bit numbers is denoted as O((n)^(μ)),then the time complexity of the generalized MSST algorithm is O(n^(2μ+1/1+μ)),which is the same as the improved SST *** practical experiments,the running time of the generalized MSST algorithm is less than that of the improved SST algorithm.

关键词： Elliptic curve generalized AGM algorithm generalized MSST algorithm SST algorithm

Characteristics Variation of Atmospheric CO_(2)and CH_(4)in Yongxing Island,South China Sea

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Journal of Ocean University of China 2024年第2期23卷 438-446页

作者： lv Honggang JIANG Yifei WANG Haiyan Key Laboratory of Marine Hazards Forecasting National Marine Environmental Forecasting CenterMinistry of Natural Resources(MNR)Beijing 100081China National Marine Environmental Forecasting Center Beijing 100081China

Using the observation data in Yongxing Island,South China Sea(SCS)from December 2013 to November 2018,the multiple time scales variation of atmospheric CO_(2)and CH_(4)were analyzed to understand their temporal variation characteristics and controlling *** regional-averaged background mole fractions of CO_(2)and CH_(4)both show a single-period sinusoidal variation with a lower value at noon and a higher value in the wee *** the seasonal scale,they exhibited a significant seasonal difference with higher values in winter and lower values in *** the annual scale,CO_(2)and CH_(4)both show an increasing trend,with an annual growth rate of approximately 3.2 ppm and 12 ppb,*** annual growth rate at this site was higher than the global *** change in atmospheric CO_(2)and CH_(4)in Yongxing Island was probably caused by the higher emission of the surrounding areas and the airflows driven by ***,the long-term and high-resolution greenhouse gases(GHGs)dataset will aid relevent researchers and decision-makers in performing more in-depth studies for GHG sources in order to derive effective strategies.

关键词： carbon dioxide methane observation backward trajectory atmospheric transport

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空气质量的模糊综合评价与曲线拟合预测模型

数学的实践与认识 2018年第6期48卷 102-108页

作者：董胜伟苏婷黄玲玲吕志伟安阳工学院数理学院河南安阳455000 华中科技大学数学与统计学院湖北武汉430074

公众的健康在很大程度上受空气质量制约，对空气质量进行预测与评价具有十分重要的意义．首先针对空气质量评价问题，将模糊综合评价方法和层析分析方法相结合，建立了空气质量的模糊综合评价模型．其次针对空气质量预测问题，根据最小... 详细信息

公众的健康在很大程度上受空气质量制约，对空气质量进行预测与评价具有十分重要的意义．首先针对空气质量评价问题，将模糊综合评价方法和层析分析方法相结合，建立了空气质量的模糊综合评价模型．其次针对空气质量预测问题，根据最小二乘理论，建立了不同污染物浓度值的滑动窗口预测模型．最后选择安阳市空气污染物浓度年度均值进行了模型验证．实验结果表明，评价与预测模型具有精确度较高，误差率小的优点，具有较高的实用性．

关键词：模糊综合评价层次分析法曲线拟合权重

Transcriptomic analysis reveals the effects of maternal exposure to bisphenol AF on hypothalamic development in male neonatal mice

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Journal of Environmental Sciences 2024年第7期141卷 304-313页

作者： Lin lv Yuanyuan Li Xuanyue Chen Zhanfen Qin State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

Fragmented data suggest that bisphenol AF(BPAF),a chemical widely used in a variety of products,might have potential impacts on the ***,we employed male neonatal mice following maternal exposure to explore the effects of low-dose BPAF on hypothalamic development by *** found that maternal exposure to approximately 50μg/(kg·day)BPAF from postanal day(PND)0 to PND 15 altered the hypothalamic transcriptome,primarily involving the pathways and genes associated with extracellular matrix(ECM)and intercellular adhesion,neuroendocrine regulation,and neurological *** RNA analysis confirmed the changes in the expression levels of concerned ***,we further revealed that low-dose BPAF posed a stimulatory impact on pro-opiomelanocortin(POMC)neurons in the arcuate nucleus of the hypothalamus and induced the browning of inguinal white adipose *** findings indicate that developmental exposure to low-dose BPAF could interfere with hypothalamic development and thereby lead to alterations in the ***,5000μg/(kg·day)BPAF caused slighter,non-significant or even inverse alterations than the low dose of 50μg/(kg·day),displaying a dose-independent *** observations suggest that the the dose-independent effects of BPAF might be associated with oxidative stress and inflammatory responses caused by the high ***,our study highlights a risk of low-dose BPAF to human neuroendocrine regulation and metabolism.

关键词： Bisphenol AF Hypothalamus Transcriptomic alteration Pro-opiomelanocortin(POMC)neurons White adipose tissue browning

“双全双成果”新能源汽车技术专业(群)创新团队教学质量评价体系研究与实践

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评价与管理 2024年第2期22卷 1-6页

作者：吕玲淄博职业学院山东淄博255300

高等职业院校要强化质量意识,教学质量评价在教学质量保证中占据举足轻重的地位。为准确评价教师教学质量,并不断提升教师教学质量意识及能力,第二批国家级职业教育教师教学创新团队课题组以“双高计划”建设单位淄博职业学院新能源汽... 详细信息

高等职业院校要强化质量意识,教学质量评价在教学质量保证中占据举足轻重的地位。为准确评价教师教学质量,并不断提升教师教学质量意识及能力,第二批国家级职业教育教师教学创新团队课题组以“双高计划”建设单位淄博职业学院新能源汽车技术专业(群)为试点,立足专业及行业特点,针对调研发现的现行教学质量评价中存在的评价机制缺乏系统性、评价指标体系设计缺乏依据、评价内容陈旧、评价指标描述抽象等问题,率先提出“双全双成果”新能源汽车技术专业(群)创新团队教学质量评价体系,为教育行政主管部门制定新能源汽车技术专业(群)发展宏观政策提供决策依据,也为全国新能源汽车技术创新团队建设起到指引和借鉴作用。

关键词：教学质量评价全流程全周期课堂学习成果综合培养成果

Drought decreases the positive impact of warming on an alpine grassland community

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Science China Earth Sciences 2024年第10期67卷 3226-3238页

作者： Wang A Wangwang lv Yang ZHOU Bowen LI Jianping SUN Jingya lv Lanying CHEN Dorji TSECHEO Shiping WANG Key Laboratory of Tibetan Plateau Earth Resources and EnvironmentInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China School of Ecology and Environment Tibet UniversityLhasa 850000China University of the Chinese Academy of Sciences Beijing 100049China

Temperature and precipitation are the main factors determining plant community succession and aboveground net primary productivity(ANPP)in natural ***,most climate manipulative experiments have mainly focused on their impacts in isolation,especially in alpine *** we explored the relative effects and interaction of warming and precipitation alteration on succession and ANPP using a 7-year experiment involving warming with precipitation alteration(increase(IP)or decrease(DP))in precipitation relative to ambient precipitation(AP)on the Tibetan *** results showed that warming and warm-wet conditions increased species richness,diversity index,height and cover of overall ***,decreasing precipitation reduced them,but increased *** and the rate of change in community ***,warming mitigated the impacts of decreased precipitation on plant community composition,and the interactive effects of warming and altered precipitation on cover,height and plant ANPP varied with year and plant ***,warming increased community ANPP through increases in forb ANPP or non-dominant species ANPP and biodiversity regardless of change in ***,decreased precipitation reduced community ANPP via decreases in the ANPP of sedges and forbs and *** alteration affected the relationship between biodiversity and community ANPP regardless of warming(IP

关键词： Alpine grassland Climate warming Precipitation alteration Community composition Biodiversity Above-ground net primary productivity

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Pollution characteristics and quantitative source apportionment of heavy metals within a zinc smelting site by GIS-based PMF and APCS-MLR models

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Journal of Environmental Sciences 2024年第10期144卷 100-112页

作者： Huagang lv Zhihuang Lu Guangxuan Fu Sifang lv Jun Jiang Yi Xie Xinghua Luo Jiaqing Zeng Shengguo Xue School of Metallurgy and Environment Central South UniversityChangsha 410083China Zhuzhou Qingshuitang Technology Co. Ltd.Zhuzhou 412000China New World Environment Protection Group of Hunan Changsha 410083China

The abandoned smelters present a substantial pollution threat to the nearby soil and *** this study,63 surface soil samples were collected from a zinc smelter to quantitatively describe the pollution characteristics,ecological risks,and source apportionment of heavy metal(loid)s(HMs).The results revealed that the average contents of Zn,Cd,Pb,As,and Hg were 0.4,12.2,3.3,5.3,and 12.7 times higher than the risk screening values of the construction sites,***,the smelter was accumulated heavily with Cd and Hg,and the contribution of Cd(0.38)and Hg(0.53)to ecological risk was 91.58%.ZZ3 and ZZ7 were the most polluted workshops,accounting for 25.7%and 35.0%of the pollution load and ecological risk,*** influence of soil parent materials on pollution was minor compared to various workshops within the *** with PMF,APCS-MLR and GIS analysis,four sources of HMs were identified:P1(25.5%)and A3(18.4%)were atmospheric deposition from the electric defogging workshop and surface runoff from the smelter;P2(32.7%)and A2(20.9%)were surface runoff of As-Pb foul acid;P3(14.5%)and A4(49.8%)were atmospheric deposition from the leach slag drying workshop;P4(27.3%)and A1(10.8%)were the smelting process of zinc *** paper described the distribution characteristics and specific sources of HMs in different process workshops,providing a new perspective for the precise remediation of the smelter by determining the priority control factors.

关键词： Smelter site Heavy metal(loid)s Source apportionment Positive matrix factorization Absolute principal component score-multiple linear regression