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输电导线截面不均匀温度场的有限元模拟

电力学报 2018年第6期33卷 529-537页

作者：张世龙中国电力工程顾问集团中南电力设计院有限公司武汉430071

为了分析输电导线不均匀温度场,提出了一种基于有限元计算动态下输电导线截面上不均匀温度场的数值方法,可以考虑瞬态条件下导线的热传导、太阳辐射、空气对流、强制对流等环境条件因素的影响。该方法突破了传统的摩尔根公式的局限性,... 详细信息

为了分析输电导线不均匀温度场,提出了一种基于有限元计算动态下输电导线截面上不均匀温度场的数值方法,可以考虑瞬态条件下导线的热传导、太阳辐射、空气对流、强制对流等环境条件因素的影响。该方法突破了传统的摩尔根公式的局限性,获得了动态变化外界环境条件下输电导线的暂态温度场响应,得到导线截面上不均匀温度场分布。在此基础上,详细地分析了不均匀温度分布和外部环境条件之间的内在联系。结果表明:传统的摩尔根公式所预测结果在大载流量、大表面吸热系数(旧线)、高环境温度以及高太阳辐照条件下存在较大误差,在这些条件下必须考虑导线截面的温度不均匀分布。此外,传统摩尔根公式预测温度低于有限元模拟所得导线截面上的最高温度,基于它的设计偏于危险,在以上条件下其应用应该谨慎或做相应的修正处理。

关键词：架空导线不均匀温度场暂态热分析有限元模拟

Upcycling of polyethylene terephthalate to1,4-cyclohexanedimethanol in water

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Science China Chemistry 2025年

作者： Shuhui Fang Zhiwen Gao Xinrui shi Min zhang Wei zhang Yue Liu State Key Laboratory of Petroleum Molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal University Engineering Center for Sustainable Carbon Science and Technology East China Normal University Institute of Eco-Chongming

The recycling of waste polyethylene terephthalate（PET）, an extensively used polymer as plastic and fiber materials, has become an urgent topic due to the rapid generation and accumulation of plastic waste into the environment. Current chemical recycling approaches to depolymerize and convert PET into 1,4-cyclohexanedimethanol（CHDM）, an important chemical in the production of advanced polyesters, predominantly use organic solvents, such as alcohols or dioxane. Herein, we developed an environmentally friendly and economically viable pathway for converting PET to CHDM using water as the solvent. In this process, PET is sequentially hydrolyzed in water, hydrogenated to 1,4-cyclohexane dicarboxylic acid（CHDA）, and then reduced to CHDM. The PET conversion rate is self-enhanced in aqueous medium via acid-catalyzed hydrolysis by the generated CHDA intermediate. A Pd-based catalyst（e.g., Pd/C） selectively hydrogenates the arene ring of the PET monomer, terephthalic acid intermediate, and a Ru-Sn/C bimetallic catalyst reduces its COOH to CH2OH group. At optimized reaction conditions, a complete conversion of PET and 80.1% yield of CHDM are obtained. Alternatively, this approach can also efficiently produce CHDA from PET, with a yield up to 86.4%.

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Identifying the dynamic behaviors in complete reconstruction of Co-based complex precatalysts during electrocatalytic oxygen evolution

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Journal of Energy Chemistry 2025年第1期100卷 226-233页

作者： Jingfang zhang Danyang Wu Linke Cai Youluan Lu Fanpeng Cheng Lijuan shi Qun Yi Yao Liu Yi Huang Key Laboratory of Green Chemical Engineering Process of Ministry of Education Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education Hubei Key Laboratory of Novel Reactor and Green Chemical Technology School of Chemical Engineering & Pharmacy Wuhan Institute of Technology Key Laboratory of Pesticide & Chemical Biology of Ministry of Education Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction of Ministry of Education College of Chemistry Central China Normal University College of Materials Science and Engineering Fuzhou University

Transition metal-based nanomaterials have emerged as promising electrocatalysts for oxygen evolution reaction（OER）. Considerable research efforts have shown that self-reconstruction occurs on these nanomaterials under operating conditions of OER process. However, most of them undergo incomplete reconstruction with limited thickness of reconstruction layer, leading to low component utilization and arduous exploration of real catalytic mechanism. Herein, we identify the dynamic behaviors in complete reconstruction of Co-based complexes during OER. The hollow phytic acid（PA） cross-linked CoFe-based complex nanoboxes with porous nanowalls are designed because of their good electrolyte penetration and mass transport ability, in favor of the fast and complete reconstruction. A series of experiment characterizations demonstrate that the reconstruction process includes the fast substitution of PA by OH-to form Co（Fe）(OH)xand subsequent potential-driven oxidation to Co（Fe）OOH. The obtained CoFeOOH delivers a low overpotential of 290 mV at a current density of 10 mA cm-2and a long-term *** experiment results together with theory calculations reveal that the Fe incorporation can result in the electron rearrangement of reconstructed CoFeOOH and optimization of their electronic structure,accounting for the enhanced OER activity. The work provides new insights into complete reconstruction of metal-based complexes during OER and offers guidelines for rational design of high-performance electrocatalysts.

关键词： Oxygen evolution reaction

Boosting hydrocarbon conversion via Cu-doping induced oxygen vacancies on CeO2 in CO2 electroreduction

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Journal of Energy Chemistry 2025年第1期100卷 66-76页

作者： Lei Xue Tong shi Chenhui Han Heng zhang Fenrong Liu Haorun Li Yan Wang Xiaojun Gu Shanghong Zeng Inner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials School of Chemistry and Chemical Engineering Inner Mongolia University State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Institute of Catalysis Department of Chemistry Zhejiang University National Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization Baotou Research Institute of Rare Earths

Conversion of CO2back to hydrocarbons is the most direct way of closing the“carbon cycle”,and its significance is further enlarged if this process is driven by renewable energies such as ***,precisely controlling the product selectivity towards hydrocarbons against the competitive hydrogen evolution remains challenging,especially for Cu-based ***,we report a novel defect engineering strategy,by which Cu-doping-induced oxygen vacancies on CeO2nanorods were effectively created,with adjustable vacancy/Cu *** resulting optimum catalyst shows up to 79% catalytic current density to hydrocarbons （excluding CO）,with 49% faradaic efficiency to *** and density functional theory unveil that the ratio between oxygen vacancy and Cu affects significantly the formation of*CHO and activation of H2O,which leads to the following deep hydrogenation to *** findings may spur new insights for designing and developing more controllable chemical process relevant to CO2utilization.

关键词： Nanorods

牺牲阳极和外加电流联合保护法在长输管道中的应用研究

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表面技术 2019年第8期48卷 286-295页

作者：施云芬孙树森张世龙魏嘉馨王伦谭雨清东北电力大学化学工程学院吉林吉林132011 华电潍坊发电有限公司山东潍坊261000 吉林松花江热电有限公司吉林吉林132011

目的针对传统阴极保护在长输管道方面存在的不足,研发出新型牺牲阳极和外加电流联合阴极保护埋地管道的装置及方法。方法通过牺牲阳极和外加电流单独的优化实验,找到最佳的牺牲阳极材料及规格和外加电流的电压,制备优良的准固态电解质,... 详细信息

目的针对传统阴极保护在长输管道方面存在的不足,研发出新型牺牲阳极和外加电流联合阴极保护埋地管道的装置及方法。方法通过牺牲阳极和外加电流单独的优化实验,找到最佳的牺牲阳极材料及规格和外加电流的电压,制备优良的准固态电解质,给装置提供稳定的运行环境,搭建出联合保护装置,将其应用在埋地管道中,实现有效的保护。结果牺牲阳极实验部分,通过对管道保护效果的对比,选择出最佳条件为5cm×5cm的镁材料,其管道的腐蚀速率为2.936×10^–3mg/(***^3),阳极的消耗速率为0.135×10^–3mg/(***^3),所产生的电流最大可达0.113A,稳定时电流趋于0.07A。外加电流实验部分,通过对管道保护效果的对比,选择出最佳条件为1V的电源电压,其管道的腐蚀速率为2.150×10^–3mg/(***^3),并且其电能的消耗最少。准固态电解质实验部分,通过对溶剂、溶质、凝胶剂和金属电解质的优化,制备出电导率稳定在5.83mS/cm左右、挥发度小于0.2%、显碱性的准固态电解质。在最佳条件下搭建出联合保护装置,通过与单独的传统阴极保护法对比,镁阳极消耗量为1.875g,阳极消耗速率为0.123×10^–3mg/(***^3),消耗速率下降了10%,管道的腐蚀速率为0.82×10^–3mg/(***^3),下降了62%左右,并且可以有效地减少防护过程中的电能消耗。结论牺牲阳极和外加电流联合保护法在埋地管线中可以达到有效的保护,相比牺牲阳极和外加电流单独实验的保护指标,有明显的提升。

关键词：牺牲阳极外加电流准固态电解质联合保护埋地管道腐蚀速率

Oxygen vacancies enriched Ir/WOx catalysts for the directly chem-catalytic conversion of cellulose to ethanol

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Tungsten 2025年第1期7卷 88-99页

作者： Yu-Jing Weng Zhao-Ying Ding Ying-Chao Li Yuan-Feng Wu Yuan-Yang Xu Rui Chen Xiao-Lei Zhao Hai-Yong Wang Da-Lei zhang Yu-long zhang Henan Key Laboratory of Coal Green Conversion and International Joint Laboratory of Coal Clean Utilization College of Chemistry and Chemical Engineering Henan Polytechnic University Key Laboratory of Renewable Energy Guangzhou Institute of Energy Conversion Chinese Academy of Sciences Liaoning Institute of Energy Technology

Tungsten and its oxides are highly versatile catalysts with unique properties that hold great promise for a wide array of applications,including biological pathways and chemical *** chemo-catalysis of cellulose to ethanol presents a promising avenue for ethanol synthesis with the potential for enhanced efficiency compared to conventional methods,offering a sustainable and carbon-neutral alternative to existing petrochemical and biological ***,Ir/WOxcatalysts enriched with oxygen vacancies were meticulously prepared and demonstrated remarkable catalytic performance in converting cellulose to ethanol directly in the presence of tungstic *** catalyst achieved a high ethanol yield of 66.5%under optimal reaction conditions,approaching the theoretical yield limit of traditional ethanol *** results revealed the presence of oxygen defects,Bronsted/Lewis acidity,and Ir nanoclusters on the catalyst surface,working synergistically to facilitate the cascade catalysis of cellulose hydrolysis,sugar retro-aldol condensation reaction,and C2 intermediate hydrodeoxygenation to *** situ Fourier transform infrared spectrometer analysis confirmed the catalyst's ability to enhance the adsorption and activation of ethylene glycol for ethanol *** manipulating subtle structural features,this study offers a fresh perspective on tungsten group catalyst design and underscores the importance of synergistic effects among catalytic sites for the efficient production of ethanol from cellulose.

关键词： Cellulosic ethanol Chem-catalysis Hydrogenolysis Retro-aldol condensation Tungsten

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基于RBAC的SSO统一权限管理方法

计算机工程与设计 2009年第9期30卷 2139-2141,2144页

作者：张世龙沈玉利广东海洋大学信息学院广东湛江524088

针对RBAC(role_based access control)模型不能直接应用到SSO(single sign_on)系统中的问题,分析了RBAC模型的权限获取方式,指出不能直接应用的原因。引入XML文档存储用户在系统中的权限,改进用户权限获取方式及流程,定义权限验证方法... 详细信息

针对RBAC(role_based access control)模型不能直接应用到SSO(single sign_on)系统中的问题,分析了RBAC模型的权限获取方式,指出不能直接应用的原因。引入XML文档存储用户在系统中的权限,改进用户权限获取方式及流程,定义权限验证方法统一接口,降低RBAC模型同应用系统的耦合性,提出了改进的RBAC统一权限管理模型和实施方法,并在实际应用中得以实现和验证。

关键词：基于角色的访问控制扩展标识语言通用性低耦合单点登陆

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基于模糊数学分析下的香蕉果醋工艺改进研究

中国调味品 2021年第9期46卷 121-124页

作者：张世龙李少觐川北幼儿师范高等专科学校四川广元628017 新乡学院药学院河南新乡453003

香蕉果醋营养价值丰富,含有多种生物活性物质和微量元素,具有清热解毒、清肺润肠、降血压和利尿等多种药用功能,是一种食药兼备的果醋。该研究以香蕉果醋生产工艺条件为研究对象,对香蕉果醋的生产流程进行分析,建立香蕉果醋的综合感官... 详细信息

香蕉果醋营养价值丰富,含有多种生物活性物质和微量元素,具有清热解毒、清肺润肠、降血压和利尿等多种药用功能,是一种食药兼备的果醋。该研究以香蕉果醋生产工艺条件为研究对象,对香蕉果醋的生产流程进行分析,建立香蕉果醋的综合感官评价标准。通过使用模糊数学矩阵方法进行分析,分别建立果醋发酵过程中的初始酒精度、接种量、发酵温度、pH值和发酵周期对香蕉果醋品质的影响,并最终选取其中3个影响最为明显的因素进行正交试验。结果表明,香蕉果醋生产工艺过程中,最佳的醋酸发酵流程为初始酒精度8%、接种量4%和发酵温度32℃技术工艺条件组合时,获得的香蕉果醋工艺综合评价为86.5分,为香蕉果醋工艺的改进提供了参考依据。

关键词：香蕉果醋模糊数学加工工艺优化

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基于删除序偶的传递闭包求解算法

计算机工程与设计 2009年第8期30卷 1907-1909,1913页

作者：张世龙沈玉利广东海洋大学信息学院

针对在已有传递闭包的基础上删除序偶后的传递闭包求解问题,提出一种基于传递闭包的传递闭包动态求解算法,给出了其形式化描述形式,并给出了算法的详细证明过程。该算法在已有的传递闭包基础上,通过把新删除序偶及该序偶的所有依赖间接... 详细信息

针对在已有传递闭包的基础上删除序偶后的传递闭包求解问题,提出一种基于传递闭包的传递闭包动态求解算法,给出了其形式化描述形式,并给出了算法的详细证明过程。该算法在已有的传递闭包基础上,通过把新删除序偶及该序偶的所有依赖间接指向序偶从已有传递闭包中删除实现求解过程,从而使算法的时间复杂度降低为O(n2),并且不受稀疏矩阵或序偶链的链长等不确定因素影响,最后通过一个实例说明了该算法的执行过程。

关键词：二元关系传递闭包删除序偶时间复杂度动态算法