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COMPUTER SIMULATION OF CONTINUOUS ELECTROMAGNETIC STIRRING FOR MAKING RHEOLOGIC SEMI-SOLID SLURRY OF ZL112Y ALUMINUM ALLOY

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Chinese Journal of Mechanical Engineering 2008年第6期21卷 108-114页

作者： LIU changming yang Ling ZUO Hongzhi College of Material Science and Engineering Chongqing University Chongqing 400044 China

To realize the technology of fabricating the rheologic semi-solid slurry of ZL112Y aluminum alloy via continues electromagnetic stirring process, ANSYS software was used to simulate electromagnetic force field and fluid velocity field in the alloy melt in a crucible tube in three coils. In the first section of the paper, eletromagnetic force field and fluid velocity field caused by single coil were simulated. The result of this simulation gives an average velocity of 3.2 cm/s and it is called critical velocity because a fluid velocity over it will cause a fine and spherical structure of solid primary a in a semi-solid melt. And, from this result, a reasonable temperature of semi-solid of the alloy and an electrical current intensity were established. The electrical current intensity of the result of this simulation corresponded to the current intensity used in a practice experiment, in which the primary α was obviously refined and sphericized. Based on this simulation of single coil electromagnetic stirring, in the second section of the paper, eletromagnetic force field and fluid velocity field caused by three coils were simulated. The result of the simulation shows that, 1） there is a semi-solid zone of 32 mm from bottom of the crucible tube to the upper; 2） the electrical current intensities of three coils of 400 A, 600 A, and 400 A, which were set to top range, middle range and bottom range of the tube, respectively, were the optimum parameters of electromagnetic current intensity under the condition of this investigation; and 3） under effect of these electromagnetic current intensity, the fluid velocities of the melt in the tube were 6.3 cm/s in top range, 3.75 cm/s in middle range, and 3.9 cm/s in bottom range of it, respectively.

关键词： Electromagnetic stirring Electromagnetic force field Fluid velocity field Rheologic semi-solid slurry Computer simulation

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Responses of butachlor degradation and microbial properties in a riparian soil to the cultivation of three different plants

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Journal of Environmental Sciences 2011年第9期23卷 1437-1444页

作者： changming yang Mengmeng Wang Haiyan Chen Jianhua Li State Key Laboratory of PoUution Control and Resource Reuse Tongji University Shanghai 200092 China Key Laboratory of yangtze River Water Environment of the Ministry of Education Tongji University Shanghai 200092 China

A pot experiment was conducted to investigate the biodegradation dynamics and related microbial ecophysiological responses to butachlor addition in a riparian soil planted with different plants such as Phragmites australis,Zizania aquatica,and Acorus *** results showed that there were significant differences in microbial degradation dynamics of butachlor in the rhizosphere soils among the three riparian *** displays a significantly higher degradation efficiency of butachlor in the rhizosphere soils,as compared with *** and ***-life time of butachlor degradation in the rhizospheric soils of ***,***,and *** were 7.5,9.8 and 5.4 days,*** butachlor concentration in *** rhizosphere soil was 35.2% and 21.7% lower than that in *** and *** rhizosphere soils,respectively,indicating that *** showed a greater improvement effect on biodegradation of butachlor in rhizosphere soils than the other two riparian *** general,microbial biomass and biochemical activities in rhizosphere soils were depressed by butachlor addition,despite the riparian plant ***,rhizospheric soil microbial ecophysiological responses to butachlor addition significantly （P 0.05） differed between riparian plant *** to *** and ***,*** showed significantly larger microbial number,higher enzyme activities and soil respiration rates in the rhizosphere *** results indicated that *** have a better alleviative effect on inhibition of microbial growth due to butachlor addition and can be used as a suitable riparian plant for detoxifying and remediating butachlor contamination from agricultural nonpoint pollution.

关键词： riparian wetland butachlor rhizospheric degradation soil microflora enzymatic activities basal respiration

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Effect of manganese oxide-modified biochar addition on methane production and heavy metal speciation during the anaerobic digestion of sewage sludge

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Journal of Environmental Sciences 2019年第2期31卷 267-277页

作者： Jianhua Li Min Zhang Zhiyin Ye changming yang Key Laboratory of yangtze River Water Environment of the Ministry of Education Tongji University

Low organic matter content and high heavy metal levels severely inhibit the anaerobic digestion(AD) of sewage sludge. In this study, the effect of added manganese oxidemodified biochar composite(MBC) on methane production and heavy metal fractionation during sewage sludge AD was examined. The MBC could increase the buffering capacity,enhance the methane production and degradation of intermediate acids, buffer the pH of the culture, and stabilize the sewage sludge AD process. The application of MBC positively impacted methane production and the cumulative methane yield increased up to 121.97%,as compared with the control. The MBC addition can improve metal stabilization in the digestate. An optimum MBC dose of 2.36 g was recommended, which would produce up to 121.1 L/kg volatile solids of methane. After the AD process, even though most of the metals accumulated in the residual solids, they could be transformation from the bio-available fractions to a more stable fraction. The total organic-and sulfide-bound and residual fraction content at a 3 g dose of MBC that is 0.12 g/g dry matter were 51.06% and 35.11% higher than the control, respectively. The results indicated that the application of MBC could improve the performance of AD and promote stabilization of heavy metals in sewage sludge post the AD process.

关键词： Sewage sludge Anaerobic digestion Manganese oxide-modified biochar (MBC) Methane production Heavy metals Chemical species

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Linkage between water soluble organic matter and bacterial community in sediment from a shallow, eutrophic lake, Lake Chaohu, China

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Journal of Environmental Sciences 2020年第12期32卷 39-46页

作者： changming yang Jiliang Sun Yingying Chen Jing Wu Yulai Wang Key Laboratory of yangtze River Water Environment of the Ministry of Education Tongji UniversityShanghai 200092China Shanghai BaoSen Environmental Technology Co. Ltd.Shanghai 200439China School of Energy and Environment Anhui University of TechnologyMaanshan City 243002China

Lacustrine sediment played important roles in migration and transformation of its water soluble organic matter(WSOM), and the source and composition of WSOM would affect water trophic status and the fate of pollutants. However, we know little about the pathway of WSOM transformation and its driving bacterial communities in lacustrine sediment. In the present study, we investigated the spatial distribution patterns of sediment WSOM and its fluorescent fractions across Lake Chaohu using fluorescence spectroscopy, and explored WSOM compositional structure through our proposed calculated ratios. In addition, we also analyzed sediment bacterial community using Illumina sequencing technology, and probed the possible pathway of sediment WSOM transformation under the mediate of indigenous bacteria. Our results showed that the inflowing rivers affected the spatial distribution patterns of WSOM and its five fractions(including tyrosine-, tryptophan-, fulvic acid-, humic acid-like substances and soluble microbial productions), and sediment WSOM originated from fresh algae detritus or bacterial sources. In parallel, we also found that Proteobacteria(mainly γ-Proteobacteria and δ-Proteobacteria), Firmicutes(mainly Bacilli), Chloroflexi, Acidobacteria, Planctomycetes and Actinobacteria dominate sediment bacterial community. Furthermore, these dominant bacteria triggered sediment WSOM transformation, specifically, the humic acid-like substances could be converted into fulvic acid-like substances, and further degraded into aromatic protein-like and SMP substances. In addition, our proposed ratios(P-L:H-L, Ar-P:SMP and H-L ratio), as supplementary tool, were effective to reveal WSOM composition structure. These results figured out possible pathway of WSOM transformation, and revealed its microbial mechanism in lacustrine sediment.

关键词： Eutrophic lake DOM transformation Bacterial community EEMs-FRI Illumina sequencing

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Sustainable Wetland Management Using the Kunming-Montreal Global Biodiversity Framework as a Guide in the Sierra Leone Case

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Journal of Geoscience and Environment Protection 2024年第3期12卷 1-15页

作者： changming yang Aloysious Kingsley Suleiman Yi Lang College of Environmental Science and Engineering Tongji University Shanghai China UNEP-Tongji Institute of Environment for Sustainable Development (IESD) Shanghai China China Railway Bureau Group Co. Ltd. Hefei China

The Sustainable Wetland Management adopted for this study depicts that, the identification of drivers and impacts is needed first, in other to get a clearer roadmap, after which the Kunming-Montreal Global Biodiversity Framework would come into play to serve as a pathway for Sustainability. The study evaluates how Sierra Leone might implement the Framework’s proposed strategies in National Wetland Management. As a result, the research tried to thoroughly examine the factors that contribute to wetland degradation as well as the effects they have on the people who live nearby. The purposive sampling method was used to administer 385 structured questionnaires to inhabitants. The data was then processed in an Excel spreadsheet. Microsoft Publisher was used to draw the framework and a descriptive analysis was done. Results indicated that;the majority of the inhabitants of Aberdeen Creek are traders/self-employed, furthermore, the majority chose the place because it’s less expensive and nearer to the workplace, settlement expansion and pollution are the two most common degrading activities, while flooding and health-related issues are some of the consequences, and the Kunming-Montreal Global Biodiversity Framework is regarded to be a perfect tool for wetland management. It was concluded that to accomplish the objectives in the framework, it is necessary to have both political and social will. Satellite data and water quality research are further needed to validate the report.

关键词： Kunming-Montreal Wetland Management Urbanization Biodiversity Aberdeen Creek

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从日语“运动”相关概念考察日本“运动人类学”发展及对我国的启示

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西安体育学院学报 2016年第6期33卷 694-700页

作者：杨长明吉林大学体育学院长春130012

对于"体育"和"运动"两个名词的概念、内涵,以及使用界限,目前在我国体育(运动)学术界仍然存在各种各样的理解,至今没有一个被普遍认同的界定。"体育"一次由日本传入我国,且我国体育(运动)人类学研究受日本影响。运用人类学参与观察(fiel... 详细信息

对于"体育"和"运动"两个名词的概念、内涵,以及使用界限,目前在我国体育(运动)学术界仍然存在各种各样的理解,至今没有一个被普遍认同的界定。"体育"一次由日本传入我国,且我国体育(运动)人类学研究受日本影响。运用人类学参与观察(fieldwork)的研究方法,对日语中体育、運動、スポーツ的释义,以日本运动人类学组织机构及其发展为对象,对日本运动(体育)人类学领域进行研究。研究发现,日本运动人类学发展近30年,已经形成了科研、教育、交流"三足鼎立"的局面,而我国运动(体育)人类学发展至今已25年,对于学科思路、组织定位、发展体系等方面依然有待完善,而日本的经验值得借鉴和参考。

关键词：日本体育运动人类学启示

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Optimum Quality Level （OQL） ——The Main Proposition of Quality Economics

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Chinese Business Review 2005年第5期4卷 61-63页

作者： Jianhua Zhao changming yang Qingying Tong China University of Geosciences Quality Association of Jiangxi

This paper discusses the Optimum Quality Level （OQL） controlling under the situation of competition and monopoly. While analyzing traditional OQL, we propose a new concept-Opportunity Revenue （OR）-to analyze the principle how enterprise pursues excellent quality to develop quality competition for OR. We further discuss how to decide Optimum Quality in monopoly market.

关键词： Optimum Quality Level Opportunity Revenue (OR) monopoly market

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巢湖市环城河沉积物重金属形态及垂直分布特征

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同济大学学报（自然科学版） 2013年第9期41卷 1404-1410页

作者：杨长明张芬徐琛同济大学长江水环境教育部重点实验室上海200092

采用改良的连续提取法（BCR）对巢湖市环城河沉积物重金属总量及其赋存形态进行了测定和分析．结果表明，巢湖市环城河采样点表层（O～10cm）沉积物中重金属的质量分数分别为29．5 ～224．3mg·kg^-１（Pb），21．3～78．1nag·kg^-１... 详细信息

采用改良的连续提取法（BCR）对巢湖市环城河沉积物重金属总量及其赋存形态进行了测定和分析．结果表明，巢湖市环城河采样点表层（O～10cm）沉积物中重金属的质量分数分别为29．5 ～224．3mg·kg^-１（Pb），21．3～78．1nag·kg^-１（Ni），67．5～1126．3mg·kg^-１（Cr），50．7～217．4mg·kg^-１（Cu）；新城区西环城河沉积物重金属的质量分数明显高于老城区东环城河；其中以Cr的质量分数在不同采样点差异最为显著．不同采样点沉积物中重金属总量随深度变化特征差异明显，西环城河沉积物不同深度重金属的质量分数较低，且随深度变化较小；受污染较严重的东环城河沉积物不同深度重金属的质量分数普遍较高，且垂直变化波动较大；所调查的4个沉积物柱状样能较好表征周边环境现状和污染历程．4个采样点不同深度沉积物重金属的可交换及碳酸盐结合态的质量分数占总量的百分比均不超过5％，Pb主要以铁锰氧化物结合态存在；Ni主要以残渣态存在；Cr主要以有机物及硫化物结合态和残渣态存在；Cu则主要以铁锰氧化物结合态和残渣态存在；不同采样点柱状沉积物各重金属形态垂向分布也存在显著差异．次生相与原生相分布比值（Rsp）法分析结果显示，巢湖市东环城河2个采样点柱状沉积物Rsp值明显高于西环城河，其重金属潜在污染生态风险较高，其中Pb和Cr属于中度或重度污染水平．

关键词：巢湖流域城市内河柱状沉积物重金属形态垂直分布次生相与原生相分布比值法

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羧甲基-β环糊精对锑-萘复合污染土壤的淋洗修复效果及机制

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环境科学学报 2022年第7期42卷 434-445页

作者：王汉宇杨长明同济大学环境科学与工程学院长江水环境教育部重点实验室上海200092

为了探究羧甲基-β-环糊精(CMCD)对重金属锑(Sb)-萘(Nap)复合污染土壤的淋洗效果及修复机理,采用批量振荡淋洗和实际土柱淋洗的方法,比较了不同条件下的淋洗效果.结果表明,10 g·L^(-1)的CMCD淋洗效果最好,在pH=4时更有利于其对锑和萘... 详细信息

为了探究羧甲基-β-环糊精(CMCD)对重金属锑(Sb)-萘(Nap)复合污染土壤的淋洗效果及修复机理,采用批量振荡淋洗和实际土柱淋洗的方法,比较了不同条件下的淋洗效果.结果表明,10 g·L^(-1)的CMCD淋洗效果最好,在pH=4时更有利于其对锑和萘的吸附,最大去除率分别达到94.82%和93.59%.土柱淋洗实验表明,淋洗速率为2 mL·min^(-1)时效果最好,且间隔淋洗效果略好于连续淋洗,污染物穿透曲线则表明CMCD对萘的吸附迁移作用更大.对淋洗前后的环糊精材料采用3种方式进行表征,FTIR检测结果表明CMCD主要通过表面的羧基、羟基与Sb络合从而将其吸附去除;核磁氢谱和热重分析结果表明CMCD的空腔与萘发生了包合作用.因此,本研究证明CMCD主要通过表面基团络合-Sb、内部空腔包合-萘的方式修复复合污染土壤,可作为性能良好的淋洗剂应用于重金属与多环芳烃复合污染土壤修复工艺中,为环糊精在场地复合污染修复的应用提供一定的理论和参数支持.

关键词：锑-萘复合污染土壤土壤淋洗修复羧甲基-β-环糊精(CMCD) 吸附机理工艺参数

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合肥市南淝河不同排口表层沉积物磷形态分布特征

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环境工程学报 2014年第9期8卷 3704-3710页

作者：沈烁杨长明杨殿海同济大学教育部长江水环境重点实验室上海200092

对合肥市南淝河不同排口处表层沉积物进行了采样,并采用修正后的标准测试程序SMT和钼锑抗紫外分光光度法测定了其中的总磷(TP)、无机磷(IP)、有机磷(OP)、铁/铝磷(Fe/Al-P)和钙磷(Ca-P),同时分析了各形态磷之间以及与沉积物有机质之间... 详细信息

对合肥市南淝河不同排口处表层沉积物进行了采样,并采用修正后的标准测试程序SMT和钼锑抗紫外分光光度法测定了其中的总磷(TP)、无机磷(IP)、有机磷(OP)、铁/铝磷(Fe/Al-P)和钙磷(Ca-P),同时分析了各形态磷之间以及与沉积物有机质之间的相关性。结果表明,由于各排口附近不同的水动力条件,污染状况以及沉积环境,各排口表层沉积物总磷(TP)的质量分数存在显著差异,其值在771.23~3 065.36 mg/kg之间,除二里河排口(S15)沉积物磷以钙磷(CaP)为主外,其他采样点表层沉积物磷均以铁/铝磷(Fe/Al-P)为主,各形态P的最低值均在位于南淝河上游的S4点,TP、IP、Fe/Al-P的最大值均出现在位于望塘污水厂排口下游60 m处的S6点,潜在释放磷比例最大值在南淝河上游受农业面源污染影响较大的S3点。沉积物各形态磷之间存在着不同程度的相关性,各形态磷与有机质存在着显著的正相关。以上结果表明,南淝河沉积物磷形态分布特征受排口类型影响显著,其中城市污水处理厂尾水可能是受纳水体沉积物重要的磷源。

关键词：南淝河不同排口表层沉积物不同磷形态

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