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Spatial Distribution Characteristics of Heavy Metals Cu and Zn in Coastal Wetland Sediments

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Asian Agricultural Research 2018年第1期10卷 24-28页

作者： Huanqiang ZHENG zaiwang zhang Chenxi zhang College of Resources and Environmental Engineering Binzhou University

The content of Cu,Zn in the sediments from coastal wetlands of the Yellow River Delta was determined.The results showed that:(i)The content of Cu,Zn range was 16.70-50.40 mg/kg,18.15-48.80 mg/kg,respectively.The mean content of Cu,Zn was 31.12mg/kg,36.74 mg/kg,respectively.Compared with the soil environmental background values of Shandong Province,the content of Cu was excessive,while the content of Zn was below the background.(ii)The concentrations of Cu,Zn in sediment in the coast of the Yellow River Delta were higher than in the other two areas.(iii)Vertical distribution characteristics of the concentrations of Cu,Zn were increasing with depth.The maximum content of Cu,Zn was 80-100 cm,in general,the content of Cu,Zn in the bottom sediments was higher than that in the surface sediments.The growth and decline trends of Zn in Tamarix and Suaeda areas were much the same and all higher than in the Phragmites communis area.(iv)The distribution characteristics of Cu concentration in different vegetation cover in sediment is Suaeda>Phragmites communis>Tamarix,which reflected different effects on retention of Cu in the sediments because of the different vegetation types.The highest content of Zn in the 0-20 cm sediments in Tamarix area was 44.07 mg/kg.

关键词： The Yellow River Delta Coastal wetland Sediments Heavy metal Spatial distribution

Spatial Distribution of Heavy Metals in Sediments of Tamarix chinensis Wetland on the South Bank of Bohai Bay

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Asian Agricultural Research 2019年第11期11卷 43-47页

作者： Huanqiang ZHENG zaiwang zhang Junlu MA College of Biological and Environmental Engineering Binzhou UniversityBinzhou 256600China

In order to understand the spatial distribution of heavy metals in coastal wetlands,Tamarix chinensis wetlands on the south bank of Bohai Bay were selected as the research object.The content of Cr,Mn,Ni,Zn and Cu in soil was determined by sampling method in April 2018.The spatial distribution characteristics of heavy metals and causes were studied.The results showed that except for Cr,Ni and Zn,the content of other heavy metals in this area did not exceed the background value of soil environment in Shandong Province.The study area was slightly polluted by these three heavy metals.In the vertical direction,the content of Cr,Mn,Cu and Ni followed the law of surface layer>middle layer>bottom layer,while the content of Zn was higher in the bottom layer,which needed to be further studied.In the horizontal direction,the content of the five heavy metals was not significantly different according to the distance from the coastline.There was no significant difference in the content of heavy metals between rhizosphere soil and non-rhizosphere soil.There was a significant correlation between the content of heavy metal elements,except Mn,the content of heavy metals was significantly correlated with the content of soil organic matter.The content of some heavy metals was significantly correlated with the content of available phosphorus and ammonium nitrogen.

关键词： Bohai Bay Tamarix chinensis wetland Sediment Heavy metal Spatial distribution

Contents of Heavy Metals in Typical Aquatic Products from a Market in Binzhou

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Asian Agricultural Research 2019年第11期11卷 36-39页

作者： Xuekang zhang zaiwang zhang Zhuang REN Linlin ZHAO Hui YU Shenqiang ZHAI College of Biological and Environmental Engineering Binzhou UniversityBinzhou 256600China Binzhou Bohai Middle School Binzhou 256600China

To evaluate the levels of heavy metal pollution and risks in consumption of aquatic products from a market in Binzhou,the contents of Cu,Zn,Cd,Cr and Pb in the edible part of eight aquatic species such as Ctenopharyngodon idellus were determined by inductively coupled plasma mass spectrometry.The results show that the levels of the five elements differed among different species of aquatic products.The ability of bivalves to accumulate heavy metals was significantly higher than that of fish.Compared with relevant food hygiene standards,there was a certain excess of Cr in Ruditapes philippinarum and Penaeus vannamei.The results of human exposure risk assessment show that the THQ values of the heavy metals in the eight aquatic species were all less than 1,indicating that the consumption of these aquatic products had no potential non-carcinogenic risks.

关键词： Heavy metal Aquatic product Binzhou Ingestion risk

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钎焊工艺对双层焊管材料时效性能的影响

热加工工艺 2024年第9期53卷 55-58,63页

作者：刘顺明张志敏龙佳明庞二帅梁斌李悦刘再旺首钢京唐钢铁联合有限责任公司制造部河北唐山063210 首钢集团有限公司技术研究院北京100043

使用退火模拟器对双层焊管用钢带进行热处理,模拟其在不同制管速度、钎焊温度下的钎焊过程。使用拉伸试验机检测不同钎焊温度及不同制管速度下钢带的屈服点延伸率和时效指数,以研究钎焊温度和制管速度对双层焊管材料时效性能的影响。结... 详细信息

使用退火模拟器对双层焊管用钢带进行热处理,模拟其在不同制管速度、钎焊温度下的钎焊过程。使用拉伸试验机检测不同钎焊温度及不同制管速度下钢带的屈服点延伸率和时效指数,以研究钎焊温度和制管速度对双层焊管材料时效性能的影响。结果表明,钎焊温度越高,材料的屈服点延伸率越小,时效指数也越小,制管的抗时效性越好。随着制管速度的提高,钎焊后钢带的屈服点延伸率和时效指数均呈增大趋势,抗时效性变差。这是由于制管生产速度增大,冷却段时间变短,渗碳体析出量减小造成的。钎焊前钢带时效指数为10.6 MPa,模拟钎焊后钢带的时效指数为76.8~104.9 MPa,其抗时效性明显变差。

关键词：双层焊管时效指数钎焊工艺

Activating sulfur oxidation reaction via six-electron redox mesocrystal NiS2 for sulfur-based aqueous batteries

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National Science Review 2023年第6期10卷 64-74页

作者： Zhoudong Yang Boya Wang Yongjin Chen Wanhai Zhou Hongpeng Li Ruizheng Zhao Xinran Li Tengsheng zhang Fanxing Bu zaiwang Zhao Wei Li Dongliang Chao Dongyuan Zhao Laboratory of Advanced Materials Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials College of Chemistry and Materials Fudan University Center for High Pressure Science and Technology Advanced Research

Sulfur-based aqueous batteries(SABs) are deemed promising candidates for safe,low-cost,and high-capacity energy storage.However,despite their high theoretical capacity,achieving high reversible value remains a great challenge due to the thermodynamic and kinetics problems of elemental sulfur.Here,the reversible six-electron redox electrochemistry is constructed by activating the sulfur oxidation reaction(SOR) process of the elaborate mesocrystal NiS2(M-NiS2).Through the unique 6e-solid-to-solid conversion mechanism,SOR efficiency can reach an unprecedented degree of ca.96.0%.The SOR efficiency is further reve aled to be closely associated with the kinetics feasibility and thermodynamic stability of the M-NiS2intermedium in the formation of elemental sulfur.Benefiting from the boosted SOR,compared with the bulk electrode, the M-NiS2electrode exhibits a high reversible capacity(1258 mAh g-1),ultrafast reaction kinetics(932 mAh g-1at 12 A g-1),and long-term cyclability(2000 cycles at 20 A g-1).As a proof of concept,a new M-NiS2‖ Zn hybrid aqueous battery exhibits an output voltage of 1.60 V and an energy density of 722.4 Wh kgcath-1,which opens a new opportunity for the development of high-energy aqueous batteries.

关键词： sulfur-based aqueous battery mesocrystal material sulfur oxidation reaction high-energy aqueous battery six-electron redox

Redox Mediator Chemistry Regulated Aqueous Batteries:Insights into Mechanisms and Prospects

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CCS Chemistry 2022年第9期4卷 2874-2887页

作者： Tengsheng zhang Qianru Chen Xinran Li Jiahao Liu Wanhai Zhou Boya Wang zaiwang Zhao Wei Li Dongliang Chao Dongyuan Zhao Laboratory of Advanced Materials Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsSchool of Chemistry and MaterialsFudan UniversityShanghai 200433

Redox mediators(RMs),serving as intermediate electron carriers or reservoirs,play vital roles in developing new charge transfer energy storage systems with high voltage or capacity in aqueous batteries.However,the underlying mechanism and selection criteria of RMs remain unclear in aqueous batteries,which hinders the further exploitation of new RMs and aqueous battery chemistries.

关键词： redox mediators aqueous batteries mechanism selection criteria high-efficiency highenergy

Ecological influence of exotic plants of Sonneratia apetala on understory macrofauna

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Acta Oceanologica Sinica 2012年第5期31卷 115-125页

作者： TANG Yijie FANG Zhanqiang CHEN Kang zhang zaiwang ZHONG Yanting AN Dong YANG Xiongbang LIAO Baowen Department of Biology Guangdong University of Education Guangzhou 510303 China Key Laboratory of Ecology and Environmental Science in Guangdong Higher Education College of Life Sciences South China Normal University Guangzhou 510631 China Administrative Office of Zhuhai Qi'ao-Dangan Island Provincial Nature Reserve Zhuhai 519000 China The Research Institute of Tropical Forestry Chinese Academy of Forestry Guangzhou 510520 China

The study aims to compare the differences of macrofauna communities of wetlands at 3-year-forest- age, 5-year-forest-age Sonneratia apetala artificial mangroves, 5-year-forest-age Kandelia candel ar- tificial mangroves with the same restoration background, and the naked tidal flat in the Qi’ao Island Mangrove Nature Reserve of Zhuhai, Guangdong Province. The results show that there were signif- icant structural differences in macrofauna communities among four kinds of habitats. The increase of biomass and species diversity of macrofauna at 3-year-forest-age S. apetala artificial mangroves was obviously faster than that at 5-year-forest-age K. candel artificial mangroves whose average tree height was close to that of 3-year-forest-age S. apetala artificial mangroves. The BIOENV analysis shows that it was related to the rapid growth of S. apetala, which rapidly changed the light level and shading conditions in the forests. The 5-year-forest-age S. apetala artificial mangroves had lower macrofauna species diversity but higher density and biomass than K. candel artificial mangroves with the same forest age. This was due to the rapid changes of physical and chemical properties of habitat soil by the ecological restoration of S. apetala artificial mangroves as well as the changed food sources possibly caused by the leaf-litter of such non-indigenous mangrove species S. apetala. However, further survey should be conducted on whether there are any negative ecological impacts of large-scale cultivation of S. apetala on macrofauna communities, so as to evaluate correctly S. apetala’s role in the restoration of coastal mangrove ecosystems.

关键词： macrofauna species diversity Sonneratia apetala artificially restored mangroves

Ecological indicators showing the succession of macrofauna communities in Sonneratia apetala artificial mangrove wetlands on Qi'ao Island at Zhuhai, South China

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Acta Oceanologica Sinica 2014年第8期33卷 62-72页

作者： TANG Yijie FANG Zhanqiang zhang zaiwang ZHONG Yanting CHEN Kang LIU Benhan FAN Junjie XIONG Tiantian LU Xiaosheng Department of Biology Guangdong University of Education Key Laboratory of Ecology and Environmental Science in Guangdong Higher Education College of Life SciencesSouth China Normal University

The Sonneratia apetala artificial mangroves in the intertidal zone of Da Wei Bay at Qi’ao Island of Zhu-hai, South China were chosen as the macrofauna succession plots while bare tidal flats of the same size were established as control plots in surrounding interference-free areas. Conventional change indicators of community structure, such as biomass and biodiversity, and indicators, such as exergy and specific exergy, which reflect the information change of overall communities, were used to analyze the succession of macro-fauna communities inS. apetala artificial mangroves. The similarities and differences in variation tendency of the different ecological indicators and their reflected ecological principles were compared. The results showed that from D-1 to D-1275 after plantingS. apetala, the biomass of the macrofauna communities first increased, which was then followed by an increase in the network relationship between the macrofauna communities （analysis of the Pielou evenness index and Shannon-Wiener diversity index）. The system in-formation （specific exergy） increased the slowest. Between D-1460 and D-2370 after plantingS. apetala, there was a decrease in biomass, network structure, and system information in the succession plots. After the decrease in the system information （the specific exergy）, there was a decline in the network relationships （Pielou evenness index and Shannon-Wiener diversity index）. Biomass was the last indicator to decrease. The similarities and differences among the different ecological indicators varied during the succession pro-cess, which reflected the relativity and differences among the indicators. This study suggested that, although the species diversity index can be an effective indicator of two types of changes （network structure and system information）, it was quite clear that species diversity measurement was not suitable for expressing the changes in biomass during the succession process. While exergy and specific exergy can provide useful information about the structural d

关键词： ecological indicators macrofauna community succession Sonneratia apetala artificial mangroves

移动边缘网络下服务缓存与资源分配联合优化策略

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通信学报 2023年第1期44卷 64-74页

作者：龙隆刘子辰陆在旺张玉成李蕾中国科学院计算技术研究所北京100190 中国科学院大学计算技术研究所北京100049

针对边缘服务器的计算与存储资源有限,过多的任务卸载将使其计算能力与负载能力不匹配,从而导致任务处理时延增加的问题,研究了基于多用户、边缘服务器以及云服务器组成的三层网络架构下的任务卸载与存储资源联合优化问题以降低系统整... 详细信息

针对边缘服务器的计算与存储资源有限,过多的任务卸载将使其计算能力与负载能力不匹配,从而导致任务处理时延增加的问题,研究了基于多用户、边缘服务器以及云服务器组成的三层网络架构下的任务卸载与存储资源联合优化问题以降低系统整体时延。由于该问题为混合整数非线性问题,因此提出了一种服务缓存与资源分配联合优化策略。首先,将原问题的连续与离散变量进行解耦为2个子问题,即服务缓存决策问题以及计算资源与通信资源联合优化问题。然后,通过重构线性化方法、松弛法以及凸优化方法对2个子问题进行交替优化迭代获得近似最优解。仿真结果表明,所提策略在低复杂度情况下能够获得近似最优解,并且与其他策略相比时延降低10%左右。

关键词：移动边缘计算多级网络服务缓存资源分配