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[Solid-phase extraction coupled with high performance liquid chromatography-triple quadrupole mass spectrometry for simultaneous determination of seven coumarins in water samples from drinking water treatment plants]

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Se pu = Chinese journal of chromatography 2025年第1期43卷 78-86页

作者： Wen-Mei Jiao Jing-Ming Yang Ce Xu Fu-Kang Gao Lu-Yao Shen Yu-Bo Yuan Zhi-Fen Guo guang Huang School of Life Sciences and Chemical Engineering Jiangsu Second Normal University Nanjing 211200 China. School of Stomatology Nanjing Medical University Nanjing 210029 China. School of Public Health Nanjing Medical University Nanjing 211166 China. Key Laboratory of Modern Toxicology Ministry of Education School of Public Health Nanjing Medical University Nanjing 211166 China.

Chlorinated coumarins, which are as cytotoxic as highly toxic halobenzoquinones toward CHO-K1 cells, have recently been identified as disinfection byproducts in drinking water disinfection processes. Therefore, detecting coumarins in water samples collected at various stages from drinking water treatment plants helps assess the formation of chlorinated coumarins in drinking water. Hence, a simple, rapid, accurate, and sensitive method for quantifying coumarins in water samples is required. In this study, a method was developed based on solid-phase extraction coupled with high performance liquid chromatography-triple-quadrupole mass spectrometry for analyzing seven coumarins in water samples from drinking water treatment plants, including 6,7-dihydroxycoumarin, 7-hydroxycoumarin, 6-hydroxy-4-methylcoumarin, 8-chloro-7-hydroxycoumarin, coumarin, 7-chloro-6-hydroxy-4-methylcoumarin, and 3,8-dichloro-7-hydroxycoumarin. Sample pretreatment involved solid-phase extraction using HLB columns, followed by elution with water and methanol, each containing 0.25% formic acid. The extracted solution was separated via gradient elution using a Phenomenex Luna C18 column (100 mm×2.0 mm, 3 mm) with 0.1% formic acid aqueous solution and methanol as the mobile phases, with analytes detected by triple-quadrupole mass spectrometry equipped with electrospray ionization source in multiple reaction monitoring mode. The matrix effect, precision, and accuracy of the developed method were investigated using raw and treated water as matrices. Matrix effects of 0.84-1.12 were recorded for the detection of 6,7-dihydroxycoumarin, 7-hydroxycoumarin, 6-hydroxy-4-methylcoumarin, and coumarin in raw water, while values of 0.67-0.70 were recorded for 8-chloro-7-hydroxycoumarin, 7-chloro-6-hydroxy-4-methylcoumarin, and 3,8-dichloro-7-hydroxycoumarin in finished water. The three chlorinated coumarins exhibited matrix effects above 0.80 after the finished water matrix had been diluted four times. These re

关键词： coumarins disinfection byproducts drinking water high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) solid-phase extraction (SPE)

紫外线消毒系统中超声波抑垢的机制及参数优化

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土木与环境工程学报（中英文） 2025年第1期47卷 221-228页

作者：陈光赵志伟李莉重庆大学环境与生态学院重庆400045

紫外消毒技术因具有无须投加化学药剂、消毒广谱性、产生副产物少等优势越来越受重视,但石英套管结垢引起的消毒效果难以保障,成为限制紫外消毒技术发展的瓶颈。在污水厂紫外线消毒渠中搭建中试试验装置,利用超声波抑制石英套管结垢,结... 详细信息

紫外消毒技术因具有无须投加化学药剂、消毒广谱性、产生副产物少等优势越来越受重视,但石英套管结垢引起的消毒效果难以保障,成为限制紫外消毒技术发展的瓶颈。在污水厂紫外线消毒渠中搭建中试试验装置,利用超声波抑制石英套管结垢,结果表明,超声波能通过延长结垢诱导期来抑制垢的生成;以相对紫外线强度为考察对象,通过单因素试验确定超声波功率、清洗周期、超声时间合适的范围分别在500~1000 W、0.5~1.0 d、20~40 min;对于使用时间为0、0.5、1、3、5 a的石英套管,超声波均有很好的抑垢效果。为了进一步优化参数,采用Box-Behnken设计法和响应面分析方法对主要因素加以优化,得到了响应面回归模型和最优解。结果表明,超声波技术抑垢清垢的优化工艺参数为超声波功率P=965 W,清洗周期T=0.5 d,超声时间t=34 min,预测相对紫外线强度最大值为1.01。通过统计学检验,模型具有良好的拟合性,在优化工艺条件下得到的相对紫外线强度预测值与试验值接近,误差为1.00%。

关键词：超声波紫外线消毒石英套管结垢响应面法

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基于语料库的朝鲜语命名实体结构特征研究

外语学刊 2025年第1期 9-18页

作者：黄政豪金光洙延边大学工学院延吉133002 延边大学外国语学院延吉133002

本文统计Klue⁃ner和Kochet⁃ner两个命名实体语料库中的新闻、评论和文化遗产文本数据包含的不同类别朝鲜语命名实体。根据统计结果分析朝鲜语命名实体的音节长度特征分布和格词尾结合率。分析结果表明,音节长度和格词尾的使用在命名实... 详细信息

本文统计Klue⁃ner和Kochet⁃ner两个命名实体语料库中的新闻、评论和文化遗产文本数据包含的不同类别朝鲜语命名实体。根据统计结果分析朝鲜语命名实体的音节长度特征分布和格词尾结合率。分析结果表明,音节长度和格词尾的使用在命名实体分类中具有一定的规律可循。本文的研究成果可用于命名实体分类工作,同时也可以为朝鲜语命名实体语料库构建提供分布结构建议。

关键词：朝鲜语格词尾命名实体识别特征提取名词分类

Consensus Control for a Kind of Dynamical Agents in Network

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International Journal of Communications, Network and System Sciences 2016年第1期9卷 29-37页

作者： hongwang Yu School of Science Nanjing Audit and University Nanjing China

This paper discusses consensus control for a kind of dynamical agents in network. It is assumed that the agents distributed on a plane and their location coordinates are measured by remote sensor and transmitted to its neighbors. By designing the linear distributed control protocol, it is shown that the group of agents will achieves consensus. The simulations are given to show the effectiveness of our theoretical result.

关键词： Distributed Control Graph Laplacian Dynamical Agents

Stabilization via Fully Actuated System Approach:A Case Study

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Journal of Systems Science & Complexity 2022年第3期35卷 731-747页

作者： DUAN guang-Ren Center for Control Science and Technology Southern University of Science and TechnologyShenzhen 518055China Center for Control Theory and Guidance Technology Harbin Institute of TechnologyHarbin 150001China

In this note,a benchmark example system which is not stabilizable by a smooth state feedback controller is considered with the fully actuated system(FAS)*** is shown that a smooth controller exists which drives the trajectories starting from a large domain in the initial value space to the origin *** a result brings about a generalization of Lyapunov asymptotical stability,which is termed as global exponential *** region of attraction is allowed to be an unbounded open set of the initial values with closure containing the *** sub-stability result may be viewed to be superior to some local stability results in the Lyapunov sense because the region of attraction is much larger than any finite ball containing the origin and meanwhile the feasible trajectories are always driven to the origin *** on this sub-stabilization result,globally asymptotically stabilizing controllers for the system can be provided in two general ways,one is through combination with existing globally stabilizing controllers,and the other is by using a pre-controller to first move an initial point which is not within the region of attraction into the region of attraction.

关键词： Feedback stabilization fully actuated system approach nonlinear systems region of attraction singularity sets

Brockett's Second Example:A FAS Approach Treatment

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Journal of Systems Science & Complexity 2023年第5期36卷 1789-1808页

作者： DUAN guang-Ren Shenzhen Key Laboratory of Control Theory and Intelligent Systems Southern University of Science and TechnologyShenzhen 518055China Center for Control Theory and Guidance Technology Harbin Institute of TechnologyHarbin 150001China

In this paper,several equivalent forms of the well-known Brockett's second example system are firstly *** stabilization of the system is then treated in the fully actuated system approach.A simple continuous time-invariant sub-stabilizing controller is designed,and the corresponding region of attraction is *** a result,all trajectories of the system starting from the characterized region of attraction are driven exponentially to the *** the region of attraction is very large,the designed sub-stabilizing controller can be directly useful in many practical *** cases where the initial values are indeed needed to be chosen out of the region of attraction,extremely simple pre-controllers can be designed,which drive the system trajectories into the designed region of attraction.A simulation of the designed control system is carried out to show the effect of the proposed approach.

关键词： Brockett integrator continuous time-invariant controllers fully actuated system approach region of attraction sub-stabilization

A Novel Method for Forecasting Freak Wave Occurrence in A Short Crested Coastal Sea

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China Ocean Engineering 2024年第1期38卷 104-116页

作者： WANG Ying-guang State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Ocean and Civil Engineering Shanghai Jiao Tong UniversityShanghai 200240China

In order to forecast the distribution of crest amplitudes and the occurrence of freak waves in a short crested coastal sea,a novel transformed linear simulation method is initially proposed in this paper.A Hermite transformation model expressed as a monotonic cubic polynomial serves as the foundation for the novel simulation *** wave crest amplitude exceedance probabilities of two sea states-one with a directional wave spectrum based on the measured wave elevation data at the Yura coast and the other with a typical directional JONSWAP wave spectrum-have been predicted using the novel simulation method that has been *** likelihood that a particular critical wave crest amplitude will be exceeded is directly correlated with the probability that freak waves will *** is shown that the novel simulation approach suggested can provide predictions that are more precise than those obtained from the Rayleigh crest amplitude distribution model,the Jahns and Wheeler crest amplitude distribution model,or the conventional linear simulation *** study also demonstrated that the nonlinear simulation method is less effective than the novel simulation method in terms of efficiency.

关键词： wave crest amplitude freak waves short crested sea transformed linear simulation

Brockett’s First Example: An FAS Approach Treatment

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Journal of Systems Science & Complexity 2022年第2期35卷 441-456页

In this note,the well-known Brockett’s first example system is treated with the fully actuated system(FAS)***,it is shown that the system can be exponentially substabilized by a smooth controller in the sense that,except those starting from initial values on the z0-axis of the initial value space,all trajectories of the designed system as well as the control signals decay to zero ***,global stabilization is realized through a way of enabling the trajectories starting from initial values on the z0-axis also to go to the *** idea is to firstly move an initial point on the z0-axis away from the axis using a pre-controller,and then to take over by the designed exponentially sub-stabilizing controller.

关键词： Exponential sub-stabilization feedback stabilization fully actuated system approach region of attraction singularity sets

Predicting Loads and Dynamic Responses of An Offshore Jacket Wind Turbine in A Nonlinear Sea

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China Ocean Engineering 2020年第5期34卷 641-650页

作者： WANG Ying-guang State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

In order to improve the simulation efficiency, a novel transformed linear Gaussian model has been first proposed in this paper for generating equivalent "nonlinear" irregular waves. It is demonstrated by calculation examples that for obtaining equivalent "nonlinear" waves with the same accuracy, the transformed linear Gaussian model is about 2.7 times faster than the traditional nonlinear simulation method and is about 2.14 times faster than the method proposed by Agarwal and Manuel(2011). The loads and dynamic responses calculation results regarding an offshore jacket wind turbine in this paper demonstrate that nonlinearly simulated irregular waves with bottom effects should be considered in order to design an un-conservative support structure for the offshore wind turbine. Furthermore, by studying the calculation results in this article we have found that the loads and dynamic responses of the offshore wind turbine when inputting transformed linearly simulated waves with bottom effects are almost identical to the corresponding values when inputting nonlinearly simulated waves with bottom effects. All these calculation results clearly demonstrate the superiority and effectiveness of using our novel transformed linear Gaussian model for predicting the wave loads and dynamic responses of an offshore wind turbine operating in a realistic nonlinear sea with bottom effects.

关键词： loads dynamic responses offshore wind turbine bottom effects nonlinear irregular sea