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High Voltage 2023年第6期8卷 1215-1224页

作者： Shuqi Li Qiang wang Dongxin He liangkai wang Qingquan Li Wen Si Shandong Provincial Key Laboratory of UHV Transmission Technology and Equipment School of Electrical EngineeringShandong UniversityJinanChina Zibo City Product Quality Inspection Institute ZiboChina School of Information and Electrical Engineering Shandong Jianzhu UniversityJinanChina

The oil‐pressboard insulation on the valve side of the converter transformer withstands pulsating square wave *** voltage contains lots of DC components and high‐order harmonics,which is likely to cause insulation *** partial discharge and space charge experiments of oil‐impregnated pressboard under DC superimposed har-monic voltage are conducted to study the effects of harmonic frequency and DC com-ponents on the discharge and charge accumulation and to explore the correlation mechanism of charge dynamic behaviour and ***,it is found that high‐order harmonic voltage promotes the partial discharge generation,but DC component sup-presses the ***,the charge inside the pressboard is mainly injected in the same polarity and accumulates over *** space charge density near the electrode increases with the increase of harmonic frequency,and the large amount of charge in-jection leads to electric field ***,the electric field direction changes faster,and the frequent charge injection and extraction behaviours make the charge recombination intensify,which promotes the *** the above analysis,the influence law of harmonic voltage on the failure of oil‐pressboard insulation is obtained,providing a theoretical basis for the structural optimisation and condition assessment of the converter transformer insulation.

关键词： harmonic insulation charge

Migration and transformation of Sb are affected by Mn(Ⅲ/Ⅳ)associated with lepidocrocite originating from Fe(Ⅱ)oxidation

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Journal of Environmental Sciences 2022年第5期34卷 308-318页

作者： Yalu Shao Qian Sun liangkai wang Weiyong Zhan Hongwei Zhang Hua Zhong State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China School of Agriculture and Food The University of MelbourneVictoria 3010Australia College of Agricultural Sciences and Engineering Hohai UniversityNanjing 210098China

Antimony(Sb)is a recognized priority pollutant with toxicity that is influenced by its mi-gration and transformation *** of Fe(Ⅱ)to Fe(Ⅲ)oxides,which is a com-mon phenomenon in the environment,is often accompanied by the formation of Mn(Ⅲ/Ⅳ)and might affect the fate of *** this study,incorporated Mn(Ⅲ)and sorbed/precipitated Mn(Ⅲ/Ⅳ)associated with lepidocrocite were prepared by adding Mn(Ⅱ)during and after Fe(Ⅱ)oxidation,respectively,and the effects of these Mn species on Sb fate were *** results indicated that the association of these Mn species with lepidocrocite obviously enhanced Sb(Ⅲ)oxidation to Sb(V),while concomitantly inhibiting Sb sorption due to the lower sorption capacity of lepidocrocite for Sb(V)than Sb(Ⅲ).Additionally,Mn oxide equivalents increased in the presence of Sb,indicating that Sb oxidation by Mn(Ⅲ/Ⅳ)associated with lepidocrocite was a continuous recycling process in which Mn(Ⅱ)released from Mn(Ⅲ/Ⅳ)reduction by Sb(Ⅲ)could be oxidized to Mn(Ⅲ/Ⅳ)*** recycling pro-cess was favorable for effective Sb(Ⅲ)***,Sb(Ⅴ)generated from Sb(Ⅲ)ox-idation by Mn(Ⅲ/Ⅳ)enhanced Mn(Ⅱ)sorption at the beginning of the process,and thus favored Mn(Ⅲ/Ⅳ)formation,which could further promote Sb(Ⅲ)oxidation to Sb(V).Over-all,this study elucidated the effects of Mn(Ⅲ/Ⅳ)associated with lepidocrocite arisen from Fe(Ⅱ)oxidation on Sb migration and transformation and revealed the underlying reaction mechanisms,contributing to a better understanding of the geochemical dynamics of Sb.

关键词： Antimony Manganese Lepidocrocite Sorption Oxidation

Bioremediation of nitrogen-and phosphorus-polluted aquaculture sediment by utilizing combined immobilized effective microorganisms and sediment aeration technology

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International Journal of Agricultural and Biological Engineering 2019年第6期12卷 192-201页

作者： liangkai wang Xiaohou Shao Ming Xu Shuang Chen College of Agricultural Engineering Hohai UniversityNanjing 210098China Key Laboratory of Efficient Irrigation-Drainage and Agricultural Soil-Water Environment in Southern China of Ministry of Education Hohai UniversityNanjing 210098China Jiangsu Provincial Academy of Environment Science Nanjing 210000China

The endogenous release of nitrogen and phosphorus from aquaculture sediment can continuously pollute the water quality in aquaculture *** this study,an integrated bioremediation approach that combined effective microorganisms(EM)with aeration techniques was designed to restore contaminated aquaculture ***,a set of laboratory-scale experiments was designed to evaluate the feasibility of the technology for the bioremediation of nitrogen and *** removal and transformation efficiency indexes of both the overlying water and sediment were *** the obtained results,the combination of sediment aeration and immobilized EM significantly improved the nitrogen and phosphorus removal rate from the overlying water and sediment when compared to other ***,a series of field-scale experiments was further implemented to assess the integrated technique in practical *** field experiments,the variation in the comprehensive trophic level index(TLI)and sediment biodegradation activities(G value)was used to assess the effect of sediment *** pond II which promotes sediment biodegradation,the values of TLI varied from 70.13 to 54.16,and the classification level changed from Hypereutrophic to a Light *** addition,the G value increased from 0.98 kg/(kg·h)to 2.12 kg/(kg·h).The organic matter(OM)and sediment thickness(ST)decreased by 17.4 g/kg and 2.3 cm,*** obtained results indicated that the combination of EM and sediment aeration might be feasible and effective for the remediation of nitrogen-and phosphorus-polluted aquaculture sediment.

关键词： effective microorganisms immobilization technology aeration aquaculture sediment bioremediation

Bacillus amyloliquefaciens (IAE635) and their metabolites could purify pollutants, Vibrio spp. and coliformbacteria in coastal aquaculture wastewater

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International Journal of Agricultural and Biological Engineering 2021年第2期14卷 205-210页

作者： Yalu Shao Hua Zhong liangkai wang Mohammed M.A.Elbashier State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China School of Agriculture and Food The University of MelbourneVictoria 3010Australia College of Agricultural Sciences and Engineering Hohai UniversityNanjing 210098China

High-density aquaculture often causes the emission of polluted water to the marine environment in the coastal areas of *** solve the aquaculture-related water quality problems,it is appropriate to adapt eco-friendly methods,such as using microbes and their metabolic products to purify polluted *** this study,the purifying effects ofBacillus amyloliquefaciens(IAE635)metabolites(poly-γ-glutamic acid;PP)and IAE635 combined with their metabolites(MP)on turbidity,COD,NO3--N,NH4+-N,Vibrio *** bacteria in coastal aquaculture wastewater were conducted in the lab and in situ *** results showed that the removal ofturbidity,COD,NH4+-Nand NO3--Nwith PP and MP was more significant(p<0.05).Compared to Control treatment(Co),the turbidity,COD,NH4+-Nand NO3--N concentrations at 24thhour were evidently reduced by 86.6%,87.5%,83.3%and 58.0%for PP,87.9%,93.5%,86.5%and 78.0%for MP,*** populations of water pathogens under PP and MP were also significantly(p<0.05)removed compared with those of Co;at 24thhour,the *** coliform bacteria were decreased by 68.7%and 66.3%forPP,75.0%and 67.1%for MP,*** water purifying effect of MP was slightly better than that of *** situ pond purification test demonstrated that MP significantly lowered the concentrations of turbidity,COD,NH4+-N,NO3--N and NO2--N,which was more effective than EM.A significantly higher(p<0.05)γ-PGA concentration and the total bacterial population for MP compared to PP indicatedthatMPpurifies the coastal aquaculture wastewaterby both flocculation and microbial *** application of MP will benefit the aquaculture industry by providing a novel method for the removal of chemical pollutants and pathogens.

关键词： coastal aquaculture Bacillus amyloliquefaciens and their metabolites(MP) bio-flocculants chemical pollutants Vibrio spp. coliform bacteria wastewater purification

Effects of organic amendments on soil properties and growth characteristics of Melon(Cucumis melo L.)under saline irrigation

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International Journal of Agricultural and Biological Engineering 2021年第5期14卷 123-129页

作者： Mohammed M.A.Elbashier Yalu Shao liangkai wang Deli Chen Hua Zhong College of Agricultural Sciences and Engineering Hohai UniversityNanjing 210098China State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China School of Agriculture and Food The University of MelbourneVictoria 3010Australia

Establishing strategies of organic amendments application to mitigate the adverse effects of saline irrigation are essential for the sustainable agriculture.A two-year pot experiment was conducted using combinations of organic amendments including effective microorganisms(EM),biochar(BC)and digestate(Di)to investigate their effects on soil and melon(Cucumis melo L.)compared with the recommended NPK fertilizer and Control(CK)under two levels of irrigation water salinity(SL0:0.25 dS/m,SL1:2.0 dS/m).Results showed combined applications of organic amendments could significantly(p<0.05)increase soil pH and organic matter(OM)compared to NPK and *** of organic amendments containing BC evidently increased the sodium adsorptive capacity(SAC)under saline water *** combined application of EM,BC and Di(EM+BC+Di)could significantly(p<0.05)improve soil available water retention under SL0 and SL1 compared with other *** also showed organic amendments application can significantly(p<0.05)enhance the photosynthetic rate(Pr)and reduce sodium ion(Na+)content in melon ***+BC+Di could significantly(p<0.05)increase water use efficiency(WUE)and fruit yield of melon under SL0 and SL1 in comparison to other *** proved that EM+BC+Di had a positive effect on soil improvement,melon growth,WUE and fruit ***,EM+BC+Di could be used as an alternative strategy for mineral NPK fertilization of melon at reasonable dosages and frequencies under saline irrigation.

关键词： organic amendments saline irrigation soil improvement melon water use efficiency

Nickel-Catalyzed Regio-and Stereoselective Defluorinative Arylation of gem-Difluorinated Cyclopropanes

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Chinese Journal of Chemistry 2024年第8期42卷 823-828页

作者： Shutao Qi Yunkai Hua liangkai Pan Junfeng Yang Junliang Zhang Department of Chemistry Fudan University2005 Songhu RoadShanghai200438 China Fudan Zhangjiang Institute Shanghai201203 China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiangHenan 453007China

Comprehensive Summary,Herein,we report nickel-catalyzed cross-coupling of gem-difluorinated cyclopropanes with boronic acids,providing the corresponding arylated 2-fluoroallylic *** approach used commercially available phosphine ligand Xantphos to obtain monofluorinated alkenes with high regioselectivity and *** studies proposed a Ni(II)-fluoroallyl pathway and excluded the radical pathway.

关键词： Nickel Monofluoroolefin Cyclopropane Regioselectivity Stereoselectivity C-C coupling Cross-coupling Synthetic methods

换流变压器油纸绝缘局部放电及电荷分布特性研究综述

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高电压技术 2020年第8期46卷 2815-2829页

作者：李清泉王良凯王培锦李斯盟山东大学特高压输变电技术与装备山东省重点实验室济南250061 西安交通大学电力设备电气绝缘国家重点实验室西安710049

油纸绝缘作为换流变压器(简称:换流变)阀侧绕组的主要绝缘形式,长期受到交直流复合电压、谐波以及极性反转等复杂工况的影响,其在电场、温度、水分等因素作用下易发生局部放电和空间电荷/界面电荷积聚,从而诱发绝缘介质劣化或击穿。为... 详细信息

油纸绝缘作为换流变压器(简称:换流变)阀侧绕组的主要绝缘形式,长期受到交直流复合电压、谐波以及极性反转等复杂工况的影响,其在电场、温度、水分等因素作用下易发生局部放电和空间电荷/界面电荷积聚,从而诱发绝缘介质劣化或击穿。为此从油纸绝缘局部放电及电荷分布特性两方面对国内外研究现状、研究热点和成果进行阐述,总结了不同电压类型、不同老化因素、不同绝缘位置等对油纸绝缘局部放电及电荷分布特性的影响规律,展望了油纸绝缘局部放电特性与机理的研究趋势,指出在极不均匀电场以及谐波、脉冲电压作用下的局部放电特性是未来研究的重点方向,并且需结合电荷分布试验/仿真/分子模拟从宏观和微观角度同时探究电荷分布与局部放电机理的内在联系。这些研究成果的总结可为基于局部放电特征的换流变在线监测技术以及换流变绝缘性能改进提供参考和借鉴。

关键词：换流变压器油纸绝缘局部放电电荷分布局放机理

MOR沸石的骨架原子抽离及其对四氢萘裂解的影响

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化学反应工程与工艺 2020年第1期36卷 26-34页

作者：丁键李经球王良楷孔德金中国石油化工股份有限公司上海石油化工研究院绿色化工与工业催化国家重点实验室上海201208

以铵型MOR沸石为母体,在酸性和碱性介质中进行了骨架硅、骨架铝原子的抽离,利用X射线衍射(XRD)、电耦合高频等离子发射光谱(ICP)、27Al/29Si核磁共振(27Al/29Si NMR)、傅里叶变换红外光谱(FT-IR)、扫描电镜(SEM)、透射电镜(TEM)和氮气... 详细信息

以铵型MOR沸石为母体,在酸性和碱性介质中进行了骨架硅、骨架铝原子的抽离,利用X射线衍射(XRD)、电耦合高频等离子发射光谱(ICP)、27Al/29Si核磁共振(27Al/29Si NMR)、傅里叶变换红外光谱(FT-IR)、扫描电镜(SEM)、透射电镜(TEM)和氮气吸脱附等方法表征了分子筛的物化性质,并考察了其催化四氢萘裂解反应的性能。结果表明,通过碱或酸处理可有效地将骨架硅和铝原子抽离,可控调变MOR沸石的骨架结构和硅铝比,达到修饰MOR沸石孔道和酸性的目的。在四氢萘催化裂解反应中,样品经碱处理脱硅后引入了介孔,单位酸密度升高,有效提高了稠环芳烃的扩散及活性位的可接触性,从而促进初始转化率的提高。样品经酸处理脱铝后,单位酸密度降低,有效抑制了双分子反应的发生及焦炭前躯体的形成,提高了活性稳定性。由于介孔结构的引入和酸密度的优化,四氢萘在碱-酸连续处理的样品上初始转化率较处理前提升近20%,目的产物选择性提高9%,同时显著改善了催化稳定性。

关键词： MOR沸石骨架原子抽离四氢萘催化裂解

1000kV特高压线路带电作业等电位过程路径优化设计

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高压电器 2020年第4期56卷 133-139页

作者：张宇娇陈嫣冉王良凯智李黄雄峰三峡大学电气与新能源学院湖北宜昌443002 合肥工业大学电气与自动化工程学院合肥230009

特高压线路电压等级高、结构尺寸大、局部场强畸变更严重等特点给带电作业提出更高的技术要求。为研究1000 kV特高压交流线路采用吊篮法等电位作业的最优路径,文中利用有限元法计算分析了作业人员等电位作业过程中的体表场强动态分布,... 详细信息

特高压线路电压等级高、结构尺寸大、局部场强畸变更严重等特点给带电作业提出更高的技术要求。为研究1000 kV特高压交流线路采用吊篮法等电位作业的最优路径,文中利用有限元法计算分析了作业人员等电位作业过程中的体表场强动态分布,并结合粒子群优化算法求解等电位作业的最优路径,最后对路径安全性进行了现场试验。研究结果表明:特高压交流直线塔带电作业人体表面最大场强约为2468 kV/m,现有防护措施能够保证带电作业人身安全;试验数据验证了路径优化方法的可行性和可靠性,为后续特高压线路其它塔型等电位作业路径选取提供设计参考。

关键词：特高压交流带电作业直线塔路径优化粒子群算法

新型粉煤灰陶粒固定化有效微生物群落对模拟水产养殖废水净化效果

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浙江农林大学学报 2020年第4期37卷 761-768页

作者：陈爽王良恺文涛毛欣宇许明邵孝侯河海大学农业工程学院江苏南京210098 河海大学南方地区高效灌排与农业水土环境教育部重点实验室江苏南京210098 北京禹冰水利勘测规划设计有限公司江苏分公司江苏南京210036 江苏省环境科学研究院江苏南京210036

【目的】以粉煤灰与池塘底泥为主要原材料,通过固定化有效微生物群落(effective microorganisms,EM)的方式制备具有高效去氮除磷的生物陶粒,用于处理污染的养殖水体。【方法】利用等温吸附试验确定最佳粉煤灰陶粒的配比,将粉煤灰陶粒与E... 详细信息

【目的】以粉煤灰与池塘底泥为主要原材料,通过固定化有效微生物群落(effective microorganisms,EM)的方式制备具有高效去氮除磷的生物陶粒,用于处理污染的养殖水体。【方法】利用等温吸附试验确定最佳粉煤灰陶粒的配比,将粉煤灰陶粒与EM固定,在氨氮、总氮、总磷质量浓度分别为50、55、20 mg·L^-1的模拟水产养殖废水中处理6 d。【结果】在预热温度300℃,烧制温度1 100℃条件下,当粉煤灰陶粒中质量比为m(粉煤灰)∶m(活性底泥)∶m(石灰石粉末)∶m(铁粉)=50∶40∶5∶5时,改性粉煤灰陶粒固定化EM对模拟水产养殖污水中氮磷的净化效果最好。6 d后,氨氮、总氮和总磷的最大去除率分别为98.67%、93.80%和45.35%。【结论】粉煤灰陶粒本身具有一定氮磷吸附净化能力,EM固定化陶粒可强化净水效果。图5表4参24。

关键词：环境保护学固定化微生物粉煤灰陶粒水产养殖废水水质净化