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Chemical Research in Chinese Universities 2001年第1期17卷 102-107页

作者： WANG Chun ming zhu li College of Chemistry and Chemical Engineering Lanzhou UniversityLanzhou 730000P.R.China

The cyclic voltammetry(CV) and the square wave technique were used for the investigations of thallium(Ⅰ) underpotential deposition(UPD) on the silver electrode. A solution of 10 \{mmol/L\} HClO 4+10 mmol/L NaCl was selected as the supporting electrolyte. The calibration plots for Tl(Ⅰ) concentration in the range of 2×10 -9 -1×10 -7 mol/L were obtained. The detection limit was 5×10 -10 mol/L. For the solutions of 4 0×10 -9 mol/L thallium added before the urine sample pretreatment procedure, the average recovery was 105 6% with a relative standard deviation(RSD) of 15 5%.

关键词： Thallium(Ⅰ) Underpotential deposition Silver rotating disk electrode Cyclic voltammetry Square wave anodic stripping voltammetry

Monitoring Mean and Variance Change-Points in Long-Memory Time Series

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Journal of Systems Science & Complexity 2022年第3期35卷 1009-1029页

作者： CHEN Zhanshou li Fuxiao zhu li XING Yuhong School of Mathematics and Statistics Qinghai Normal UniversityXining 810008China Academy of Plateau Science and Sustainability Xining 810008China Department of Applied Mathematics Xi'an University of TechnologyXi'an 710048China College of Finance Xingjiang University of Finance and EconomicsUrumqi 830012China

This paper proposes two ratio-type statistics to sequentially detect mean and variance change-points in the long-memory time *** limiting distributions of monitoring statistics under the no change-point null hypothesis,alternative hypothesis as well as change-point misspecified hypothesis are *** particular,a sieve bootstrap approximation method is proposed to determine the critical *** indicate that the new monitoring procedures have better finite sample performance than the available off-line tests when the change-point nears to the beginning time of monitoring,and can discriminate between mean and variance ***,the authors illustrate their procedures via two real data sets:A set of annual volume of discharge data of the Nile river,and a set of monthly temperature data of northern *** authors find a new variance change-point in the latter data.

关键词： Change-point monitoring long-memory time series ratio-type statistic sieve bootstrap

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Positive and negative shear lag behaviors of composite twin-girder decks with varying cross-section

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Science China(Technological Sciences) 2017年第1期60卷 116-132页

作者： zhu li NIE JianGuo JI WenYu Key Laboratory of Civil Engineering Safety and Durability of China Education Ministry Department of Civil Engineering Tsinghua University Beijing 100084 China

In steel-concrete composite twin-girder decks, wide concrete slab would undergo significant shear lag warping effect, including positive and negative. Some researchers have investigated the positive shear lag of composite decks by means of one-dimensional line model, while the studies on the negative shear lag have not yet been reported until now. In this study, a new one-dimensional analytical model of composite twin-girder decks is first proposed based on the model proposed by Dezi et al. Besides slab shear lag effect and partial connection at slab-girder interface which have been included in the model of Dezi et al., the particularity of the proposed model relies on its ability to account for variation characteristic of cross-section. Verification of the analytical model is later conducted through comparison of results from the analytical analysis and elaborate FE analysis for a simply supported composite deck with increasing depth and a two-span continuous one with decreasing depth. Finally, three kinds of structural forms of composite twin-girder decks, including cantilever, simply supported and continuous decks, are selected to carry out the analysis of positive and negative shear lag behaviors by means of the analytical model. The influences of cross-sectional variation characteristic and load type on positive and negative shear lag behaviors are mainly investigated. Additionally, a new definition on effective width for considering simultaneously positive and negative shear lag behaviors is proposed. The results from the proposed analytical model and EC4 specification are compared to provide suggestions for designers and checkers. In this study, the proposed analytical model can provide a powerful numerical tool for researchers to conduct the further investigation, and the analysis on shear lag and effective width can assist in design analysis of composite twin-girder decks.

关键词： steel-concrete composite twin-girder deck analytical model variation of cross-section positive and negative shear lagbehavior effective width

Dynamic analysis of wind turbine tower structures in complex ocean environment

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Applied Mathematics and Mechanics(English Edition) 2020年第7期41卷 999-1010页

作者： Guanzhong liU Xingming GUO li zhu Shanghai Institute of Applied Mathematics and Mechanics Shanghai Key Laboratory of Mechanics in Energy EngineeringSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China School of Mathematics and Computational Sciences Xiangtan UniversityXiangtan 411105Hunan ProvinceChina

Studying and analyzing the dynamic behavior of offshore wind turbines are of great importance to ensure the safety and improve the efficiency of such expensive *** this work,a tapered beam model is proposed to investigate the dynamic response of an offshore wind turbine tower on the monopile foundation assembled with rotating blades in the complex ocean *** environment factors like wind,wave,current,and soil resistance are taken into *** proposed model is ana-lytically solved with the Galerkin *** on the numerical results,the effects of various structure parameters including the taper angle,the height and thickness of the tower,the depth,and the diameter and the cement filler of the monopile on the funda-mental natural frequency of the wind turbine tower system are investigated in *** is found that the fundamental natural frequency decreases with the increase in the taper angle and the height and thickness of the tower,and increases with the increase in the diameter of the ***,filling cement into the monopile can effectively im-prove the fundamental natural frequency of the wind turbine tower system,but there is a critical value of the amount of cement maximizing the property of the *** research may be helpful in the design and safety evaluation of offshore wind turbines.

关键词： wind turbine tower structure dynamic analysis tapered beam fundamen-tal natural frequency complex ocean environment

基于工作分解结构的围手术期用药路径体系建设与实施效果

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药物不良反应杂志 2025年第1期27卷 30-35页

作者：邢晓敏韩冰刘东华岳玥朱莉冷萍李静青岛大学附属医院药学部青岛266000

为促进围手术期合理用药,青岛大学附属医院采用工作分解结构(WBS)项目管理方法,构建了围手术期用药路径体系。该体系的建立需要完成路径需求调研、药物使用规范制定、药物治疗临床路径制定、临床沟通与培训、效果评价与监管、信息化用... 详细信息

为促进围手术期合理用药,青岛大学附属医院采用工作分解结构(WBS)项目管理方法,构建了围手术期用药路径体系。该体系的建立需要完成路径需求调研、药物使用规范制定、药物治疗临床路径制定、临床沟通与培训、效果评价与监管、信息化用药监管和患者用药监测等7项任务,分别由不同专业的药师负责。历时4年,医院完成了抗菌、镇痛、静脉血栓栓塞预防、营养支持、气道管理药物和质子泵抑制剂等6条共性药物治疗临床路径体系的创建,对提升外科科室抗菌药物合理使用、优化患者术后疼痛管理和强化患者血栓形成风险评估等产生了显著成效。为心脏外科构建的个性化路径和对麻醉科实施的多维度药学干预也取得显著成效。因此,通过WBS构建围手术期用药路径体系,有助于细化工作任务分工,体现药师价值,提升围手术期药学服务质量。

关键词：围手术期医护临床路径药学服务工作分解结构体系建设外科药学医院管理

Dual-radiation-chamber coordinated overall energy efficiency scheduling solution for ethylene cracking process regarding multi-parameter setting and multi-flow allocation

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Chinese Journal of Chemical Engineering 2021年第6期34卷 180-197页

作者： Di Meng Cheng Shao li zhu Institute of Advanced Control Technology Dalian University of TechnologyDalian 116024China

Ethylene cracking process is the core production process in ethylene industry,and is paid more attention to reduce high energy *** of the interdependent relationships between multi-flow allocation and multi-parameter setting in cracking process,it is difficult to find the overall energy efficiency scheduling for the purpose of saving *** traditional scheduling solutions with optimal economic benefit are not applicable for energy efficiency scheduling issue due to the neglecting of recycle and lost energy,as well as critical operation parameters as coil outlet pressure(COP)and dilution *** addition,the scheduling solutions mostly regard each cracking furnace as an elementary unit,regardless of the coordinated operation of internal dual radiation chambers(DRC).Therefore,to improve energy utilization and production operation,a novel energy efficiency scheduling solution for ethylene cracking process is proposed in this ***,steam heat recycle and exhaust heat loss are considered in cracking process based on 6 types of extreme learning machine(ELM)based cracking models incorporating DRC operation and three operation parameters as coil outlet temperature(COT),COP,and dilution ratio according to semi-mechanism *** to provide long-term decision-making basis for energy efficiency scheduling,overall energy efficiency indexes,including overall output per unit net energy input(OONE),output-input ratio per unit net energy input(ORNE),exhaust gas heat loss ratio(EGHL),are designed based on input-output analysis in terms of material and energy ***,a multiobjective evolutionary algorithm based on decomposition(MOEA/D)is employed to solve the formulated multi-objective mixed-integer nonlinear programming(MOMINLP)*** validities of the proposed scheduling solution are illustrated through a case *** scheduling results demonstrate that an optimal balance between multi-flow allocation,multi-parameter setting,and D

关键词： Ethylene cracking process Energy efficiency scheduling Overall energy efficiency indexes Dual radiation chamber Multiple operation parameters Multiple energy flows

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EG定型冷链蓄冷材料的制备及性能研究

应用化工 2025年第1期54卷 147-151,156页

作者：方嵛罗孝学李珠王强强王晓杰李琳北部湾大学广西海洋工程装备与技术重点实验室广西钦州535011 五指山市生态环境监测站海南五指山572200

针对液态蓄冷剂在船舶冷链运输中不易存放,使用时常发生泄漏现象造成污染的问题。制备了芒硝-硼砂-氯化钠+氯化钾-聚丙烯酰胺/膨胀石墨(EG)定型复合蓄冷材料,并探究EG与蓄冷剂耦合的最佳配比及其热物性能。采用高温烧结法将制备的蓄冷... 详细信息

针对液态蓄冷剂在船舶冷链运输中不易存放,使用时常发生泄漏现象造成污染的问题。制备了芒硝-硼砂-氯化钠+氯化钾-聚丙烯酰胺/膨胀石墨(EG)定型复合蓄冷材料,并探究EG与蓄冷剂耦合的最佳配比及其热物性能。采用高温烧结法将制备的蓄冷剂与不同目数EG进行耦合制备系列复合定型相变材料,并对其结构与性能进行了表征。结果表明,当添加50目12%的EG时,定型蓄冷剂性能最佳且能有效提高热导系数,此时相变温度5.9℃,相变潜热108.6 J/g,随着EG目数的增加会导致相变温度与相变潜热的降低和过冷度的增加;进行承载能力实验发现,EG吸附后试纸的泄漏情况较未吸附要好,证明EG可作为骨架支撑相变材料的定型防止泄漏。研究为后续EG定型相变材料在船舶冷链运输中的应用提供有价值的借鉴参考。

关键词：膨胀石墨定型蓄冷材料吸附性冷链运输

Lateral stiffness of steel plate shear walls

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Science China(Technological Sciences) 2014年第1期57卷 151-162页

作者： NIE JianGuo zhu li Department of Civil Engineering Tsinghua University

The steel plate shear wall system has been used in a number of buildings as an innovative lateral force resistant *** often exist in the steel plate shear walls due to the various functional requirements of *** openings may negatively impact the lateral stiffness of steel plate shear ***,an experimental research was instituted to investigate the seismic behavior of steel plate shear walls,with and without *** experimental results showed that steel plate shear walls have the satisfying seismic behavior,and,as expected,the strength and stiffness characteristics of the walls were reduced due to *** a single-story wall panel FE model and an analytical deep beam model are developed in order to find the critical factors dominating the thickness reduction coefficient of wall panels with the ***,extensive parametric analysis is conducted to derive a simplified formula for the determination of the thickness reduction coefficient of wall panels with the opening for substituting solid wall panels with reduced thickness for actual wall panels with the ***,the design method for calculating the lateral stiffness is verified by some experimental programs and recommended for the routine practice of steel plate shear walls.

关键词： steel plate shear walls wall panels with the opening thickness reduction coefficient lateral stiffness design method analytical deep beam model

人工智能在中医非药物疗法治疗肌肉骨骼疾病中的应用前景

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中国骨伤 2025年第1期38卷 1-4页

作者：魏戌王旭冯天笑朱立国中国中医科学院望京医院北京100102 数智中医防治骨与关节退行性疾病北京市重点实验室北京100102 北京中医药大学北京100029

随着现代社会生活方式的改变,肌肉骨骼疾病(musculoskeletal disease,MD)已取代了创伤性疾病,成为骨科门诊最常见的病种[1-2],目前已成为我国疾病负担最为严重的大类疾病之一[3]。以中医手法、传统功法等为代表的中医非药物疗法是中医... 详细信息

随着现代社会生活方式的改变,肌肉骨骼疾病(musculoskeletal disease,MD)已取代了创伤性疾病,成为骨科门诊最常见的病种[1-2],目前已成为我国疾病负担最为严重的大类疾病之一[3]。以中医手法、传统功法等为代表的中医非药物疗法是中医防治该类疾病的常用手段[4],不仅疗效可观[5-6],同时相较于手术治疗还具有“简、便、廉、验”的特点,其中以旋提手法为代表的颈椎病手法治疗研究成果已被纳入国际指南[7],且其远期经济效益优于外科治疗[8]。

关键词：中医药肌肉骨骼疾病人工智能中医手法传统功法

黄河源区(玛曲)近20年生态环境质量动态评价

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西北林学院学报 2025年第1期40卷 209-217页

作者：朱丽刘冬皓谈嫣蓉张洋东陈文业甘肃省林业科学研究院甘肃兰州730020 甘肃敦煌西湖湿地生态系统国家定位观测研究站甘肃敦煌736200

黄河源区(玛曲)是黄河上游重要的水源涵养区和补给区,对于维持区域生物多样性、生态系统平衡和社会经济高质量发展具有重要的作用。为揭示近20 a玛曲高寒草地生态系统动态变化特征及其区域差异性,基于GEE获取的Landsat 5、7、8数据集,... 详细信息

黄河源区(玛曲)是黄河上游重要的水源涵养区和补给区,对于维持区域生物多样性、生态系统平衡和社会经济高质量发展具有重要的作用。为揭示近20 a玛曲高寒草地生态系统动态变化特征及其区域差异性,基于GEE获取的Landsat 5、7、8数据集,应用遥感生态指数评价模型及一元回归趋势线法分析玛曲植被动态变化特征。结果表明:1)归一化植被指数、湿度、热度及干度4个指标在第一主成分贡献率均达90%以上,表明构建遥感生态指数(RSEI)评价玛曲县近20 a生态环境质量是可行的。2)2000—2021年玛曲县植被覆盖度整体上以增加趋势为主,2021年高植被覆盖度面积占研究区面积的93.44%。植被覆盖度显著改善区域主要分布在玛曲县东南边缘的齐哈玛乡、采日玛乡、曼日玛乡和黄河干流之间的大片区域,面积为4458.9 km^(2),占整个县域国土面积的38.36%。3)2000—2021年玛曲县遥感生态指数整体上呈上升趋势,上升了0.047,均值为0.788,表明玛曲县生态质量处于良好水平。4)玛曲县近20 a间生态环境质量变化特征为前期退化、后期改善。

关键词：遥感生态指数植被覆盖度生态环境质量

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