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超痕量六价铬分析仪测定模拟唾液迁移玩具中的六价铬

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中国无机分析化学 2024年第5期14卷 553-559页

作者：汤骏懿莫单评广州海关技术中心广州510000

为快速定量唾液对玩具材料中六价铬的迁移量,采用模拟胃液迁移特定元素的迁移模型,在180 r/min的恒温水浴振荡器中,(37±2)℃恒温避光振荡1 h后,(37±2)℃静置1 h,模拟婴幼儿将玩具含入口中的过程。选择硝酸铵作为流动相,以Prin-Cen ONL... 详细信息

为快速定量唾液对玩具材料中六价铬的迁移量,采用模拟胃液迁移特定元素的迁移模型,在180 r/min的恒温水浴振荡器中,(37±2)℃恒温避光振荡1 h后,(37±2)℃静置1 h,模拟婴幼儿将玩具含入口中的过程。选择硝酸铵作为流动相,以Prin-Cen ONLY WATER Kit for Cr(Ⅵ)Test Fast column色谱柱作为分析柱,使用紫外可见光检测器进行测定,建立了使用超痕量六价铬分析仪测定模拟唾液迁移玩具材料中六价铬的方法。结果表明,六价铬浓度在0~2μg/L范围内线性关系良好,相关系数能达到1.000,方法检出限为0.006μg/L,方法定量限为0.019μg/L。选取三种实际样品,在低浓度和高浓度下的加标回收率能达到95.0%~105%,在0.5μg/L中等浓度水平下,加标样品的相对标准偏差在3.1%~4.4%。对三种阳性样品进行测定,均能检出较高含量的Cr(Ⅵ)。方法具有良好的准确度和精密度,能应对常见的样品类型,有着较强的适用性。

关键词：超痕量六价铬分析仪铬(Ⅵ) 模拟唾液玩具

一种基于经验模态分解和局部极大值点数的配电网高阻接地故障检测方法

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电气技术 2024年第6期25卷 14-23页

作者：唐钧益曾肖枫高伟福州大学电气工程与自动化学院福州350108 国网福建省电力有限公司泉州供电公司福建泉州362001

配电网高阻接地故障(HIF)因故障特征微弱而难以被常规装置检测到,容易引发过电压、火灾和人身触电等安全问题。本文提出一种将时频分解和阈值判断结合的HIF识别方法。首先,利用经验模态分解(EMD)对零序电流进行处理;然后,选取第二个固... 详细信息

配电网高阻接地故障(HIF)因故障特征微弱而难以被常规装置检测到,容易引发过电压、火灾和人身触电等安全问题。本文提出一种将时频分解和阈值判断结合的HIF识别方法。首先,利用经验模态分解(EMD)对零序电流进行处理;然后,选取第二个固有模态分量(IMF)作为特征分量并进行高斯滤波;最后,统计特征分量的局部极大值点的个数来判断是否发生HIF。利用PSCAD/EMTDC软件搭建10kV配电网模型进行算法验证。仿真结果表明,所提方法能够以较高的准确率将HIF和一些常见的干扰事件区分开,并且在发生噪声干扰、采样率变化、系统中性点接地方式改变及系统网络结构改变的情况下,均表现出较好的适应性。

关键词：配电网高阻接地故障(HIF) 经验模态分解(EMD) 局部极大值点数

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广东省海洋垃圾污染特征、来源及风险评价

海洋环境科学 2024年第5期43卷 696-706页

作者：邓炜华唐俊逸罗育池陈辉曾丹娜叶匡旻广东省环境科学研究院

本研究以2023年广东省11处海域（岸滩）垃圾的采样调查结果为基础，将海滩垃圾、海面垃圾和海底垃圾分别划分为城市、乡郊、渔业；沿岸、潟湖；基岩、砂泥和建设等类型，分析了海洋垃圾密度、分布和来源，利用海滩质量指数评估了海洋垃... 详细信息

本研究以2023年广东省11处海域（岸滩）垃圾的采样调查结果为基础，将海滩垃圾、海面垃圾和海底垃圾分别划分为城市、乡郊、渔业；沿岸、潟湖；基岩、砂泥和建设等类型，分析了海洋垃圾密度、分布和来源，利用海滩质量指数评估了海洋垃圾风险。结果显示，海滩垃圾、海面漂浮垃圾和海底垃圾数量密度分别为43178个/km2、5634个/km2和2747个/km2，丰、枯水期差异明显，海洋垃圾主要来源于人类海岸活动和航运/捕鱼活动，调查海滩的清洁度为“非常清洁”，安全程度为“安全”或“适度安全”，健康状况为“良好”。

关键词：海洋垃圾污染特征来源分析风险评估

基于递归径向基神经网络滑模的多功能柔性多状态开关控制方法

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电气技术 2024年第5期25卷 11-21页

作者：廖江华高伟唐钧益杨耿杰福州大学电气工程与自动化学院福州350108

近年来,新能源和电动汽车的渗透比例逐渐增高,给配电网的潮流优化和电能质量治理带来严峻挑战。针对分布式电源的随机性和间歇性问题,设计一种基于递归径向基神经网络(RRBFNN)滑模的多功能柔性多状态开关(FMS)控制方法,在实现功率交互... 详细信息

近年来,新能源和电动汽车的渗透比例逐渐增高,给配电网的潮流优化和电能质量治理带来严峻挑战。针对分布式电源的随机性和间歇性问题,设计一种基于递归径向基神经网络(RRBFNN)滑模的多功能柔性多状态开关(FMS)控制方法,在实现功率交互和多端单相接地故障柔性消弧的同时,增强FMS的抗扰能力。首先考虑扰动的影响,设计一种改进RRBFNN滑模控制方法,以克服传统滑模控制固有的抖振现象和对系统精确数学模型的依赖,并减小并网暂态冲击;柔性消弧控制采用微积分型滑模面,理论推导出0轴电压控制律,提高故障电流抑制率;进一步通过李雅普诺夫定理证明所设计方法的稳定性和收敛性。最后,在Matlab/Simulink中搭建三端口FMS及其控制系统的仿真模型,通过对比仿真验证了所提策略的可行性和有效性。

关键词：配电网柔性多状态开关(FMS) 单相接地故障柔性消弧径向基神经网络(RBFNN) 滑模控制

Mottled dolomite in the lower Cambrian Longwangmiao formation in the Northern Sichuan Basin, South China

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Petroleum 2024年第1期10卷 19-29页

作者： Xuefei Yang Hao tang junyi Zhang Yao Du Ruifeng tang Shuang Pan Xiang Zhou Yan Xu State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University Sichuan Provincial Key Laboratory of Gas Geology Southwest Petroleum University CCDC Chuandong Drilling Company Exploration Department Petrochina Southwest Oil& Gasfield Company

At the end of Early Cambrian time, the Sichuan basin（South China） was located in a wide carbonate platform, with hundreds of meters of carbonate deposited. The Longwangmiao Formation carbonate in Sichuan basin is partially to completely dolomitized, displaying a mottled texture in the northern area of the exposure. The mottled dolomitic limestone developed parallel to bedding, with shape irregular boundaries with limestone that has not been dolomitized. The mottled dolomite is composed of powder crystalline and finely crystalline dolomite, while the matrix limestone is composed of micritic calcite. the isotopic composition of mottled dolomite(δ13C = +0.29‰PDB, δ18O =-1.15‰PDB) is similar to that of micrite calcite(δ13C =-0.49‰PDB, δ18O =-1.45‰PDB). Both isotopic values and trace element data indicate that the dolomitized fluid is originated from sea water. Some beds contain gypsum pseudomorphs and mud cracks, indicating a shallow and evaporative environment with local high salinity during deposition. Dolomitization likely took place early, in part as a result of sea water salinity concentration. Trace fossils thalassinoides horizontalis, thalassinoides callianassa and planolites developed in the Longwangmiao Formation, and the sharp edges of mottled dolomite are similar to these trace fossils. The beds are intensely bioturbated. In the burrow network, the sediments and burrow fill were coarse and loose with little clay, and it is interpreted here as being easier to be dolomitized than the surrounding *** dolomitization is thus interpreted to have occurred in the burrow system, and the degree of dolomitization was related to the degree of bioturbation, which is controlled by the trace-making creatures.

关键词： Mottled dolomite Dolomitization Longwangmiao Formation Early Cambrian Northern Sichuan basin

The Curriculum and Education System of Hong Kong Tourism Higher Education -- Taking Hong Kong Polytech University as an example

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International Journal of Technology Management 2015年第9期 5-8页

作者： ZHONG lina tang junyi Beijing International Studies University Tourism Management School Beijing 100024 China

Hong Kong Polytech University is the representative of tourism higher education in Hong Kong, offering various courses in hotel management and tourism management at the Doctor, Masters and Bachelor levels, whose curriculum and education system have been quite perfect. The PolyU has cultivated a large number of high-quality professional people for the hotel and tourism industry. Excellent teachers, modem curriculum and the education concept of attaching great importance to the practice are the reasons why it can cultivate senior executives with international perspective, skills and social responsibility.

关键词： Hong Kong Polytech University tourism higher education practical ability

A chorismate mutase from Radopholus similis plays an essential role in pathogenicity

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Journal of Integrative Agriculture 2024年第3期23卷 923-937页

作者： Sihua Yang junyi Li Shuai Yang Shiqiao tang Huizhong Wang Chunling Xu Hui Xie Laboratory of Plant Nematology andResearch Centerof Nematodes of Plant Quarantine Department of Plant Patholo of Plant ProtectionSouth China Agricultural UniversityGuangzhou 510642China

In the process of infecting plants, plant parasitic nematodes release a series of proteins that play an essential role in the successful infection and pathogenesis of plant cells and tissues through stylets or body walls. In this study,based on transcriptome data, a chorismate mutase gene of Radopholus similis(RsCM) was identified and cloned,which is a single copy gene specifically expressed in the oesophageal gland and highly expressed in juveniles and females. Transient expression of RsCM in tobacco leaves showed that it was localised in the cytoplasm and nucleus of tobacco leaf cells, which inhibited the pattern-triggered immunity(PTI) induced by flg22, including callose deposition and defence gene expression, and cell death induced by immune elicitors BAX, but could not inhibit cell death induced by immune elicitors Gpa2/RBP-1. The RNA interference(RNAi) transgenic tomato of RsCM obviously inhibited the infection, pathogenicity, and reproduction of R. similis. However, the resistance of the overexpression transgenic tomato of RsCM to R. similis infection was significantly reduced, and the expression levels of two salicylic acid(SA) pathway genes(PR1 and PR5) in roots infected by the nematode were significantly down-regulated,which indicated that RsCM might be involved in the inhibition of SA pathway. The results of this study demonstrate that RsCM suppresses the host immune system and might be a new target for the control of R. similis, which also provides new data for the function and mechanism of CM genes of migratory parasitic plant nematodes.

关键词： Radopholus similis chorismate mutase plant defense transgenic tomato

Conductive Porous MXene for Bionic,Wearable,and Precise Gesture Motion Sensors

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Research 2021年第1期2021卷 1391-1401页

作者： Shengshun Duan Yucheng Lin Zhehan Wang junyi tang Yinhui Li Di Zhu Jun Wu Li Tao Chang-Hwan Choi Litao Sun Jun Xia Lei Wei Baoping Wang Joint International Research Laboratory of Information Display and Visualization School of Electronic Science and EngineeringSoutheast UniversityNanjing 210096China School of Materials Science and Engineering Southeast UniversityNanjing 211189China Center for 2D Materials Southeast UniversityNanjing 211189China Center for Advanced Materials and Manufacture Joint Research Institute of Southeast University and Monash UniversitySuzhou 215123China Department of Mechanical Engineering Stevens Institute of TechnologyHobokenNew Jersey 07030USA SEU-FEI Nano-Pico Center Key Laboratory of MEMS of Ministry of Education Collaborative Innovation Center for Micro/Nano Fabrication Device and SystemSoutheast UniversityNanjing 210096China Center for Advanced Carbon Materials Southeast University and Jiangnan Graphene Research InstituteChangzhou 213100China

Reliable,wide range,and highly sensitive joint movement monitoring is essential for training activities,human behavior analysis,and human-machine ***,most current motion sensors work on the nano/microcracks induced by the tensile deformation on the convex surface of joints during joint movements,which cannot satisfy requirements of ultrawide detectable angle range,high angle sensitivity,conformability,and consistence under cyclic *** nature,scorpions sense small vibrations by allowing for compression strain conversion from external mechanical vibrations through crack-shaped slit ***,we demonstrated that ultraconformal sensors based on controlled slit structures,inspired by the geometry of a scorpion’s slit sensilla,exhibit high sensitivity(0.45%deg^(-1)),ultralow angle detection threshold(~15°),fast response/relaxation times(115/72 ms),wide range(15°~120°),and durability(over 1000 cycles).Also,a user-friendly,hybrid sign language system has been developed to realize Chinese and American sign language recognition and feedback through video and speech broadcasts,making these conformal motion sensors promising candidates for joint movement monitoring in wearable electronics and robotics technology.

关键词： durability conformal satisfy

A novel method for extracting and optimizing the complex permittivity of paper-based composites based on an artificial neural network model

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Science China Technological Sciences 2024年第10期67卷 3190-3204页

作者： XIA ChenBin SHEN junyi LIAO ShaoWei WANG Yi HUANG ZhengSheng XUE Quan tang Min LONG Jin HU Jian School of Light Industry and Engineering South China University of Technology School of Electronic and Information Engineering South China University of Technology

Measuring the complex permittivity of ultrathin, flexible materials with a high loss tangent poses a substantial challenge with precision using conventional methods, and verifying the accuracy of test results remains difficult. In this study, we introduce a methodology based on a back-propagation artificial neural network(ANN) to extract the complex permittivity of paper-based composites(PBCs). PBCs are ultrathin and flexible materials exhibiting considerable complex permittivity and dielectric loss tangent. Given the absence of mature measurement methods for PBCs and a lack of sufficient data for ANN training, a mapping relationship is initially established between the complex permittivity of honeycomb-structured microwave-absorbing materials(HMAMs, composed of PBCs) and that of PBCs using simulated data. Leveraging the ANN model, the complex permittivity of PBCs can be extracted from that of HMAMs obtained using standard measurement. Subsequently, two published methods are cited to illustrate the accuracy and advancement of the results obtained using the proposed approach. Additionally, specific error analysis is conducted, attributing discrepancies to the conductivity of PBCs, the homogenization of HMAMs, and differences between the simulation model and actual objects. Finally, the proposed method is applied to optimize the cell length parameters of HMAMs for enhanced absorption performance. The conclusion discusses further improvements and areas for extended research.

关键词： paper-based composite honeycomb complex permittivity artificial neural networks inverse modeling

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