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Distribution of mercury and methylmercury in river water and sediment of typical manganese mining area

Journal of Environmental Sciences 2022年第9期34卷 11-22页

作者： Yongjiang Zhang Tao Sun Ming Ma Xun wang Qing Xie Cheng Zhang yongmin wang Dingyong wang College of Resources and Environment Southwest UniversityChongqing 400715China Department of Environment and Quality Test Chongqing Chemical Industry Vocational CollegeChongqing 401220China School of Agricultural Sciences Zhengzhou UniversityZhengzhou 450001China

Manganese(Mn) ores contain substantial concentrations of mercury(Hg), and mining and smelting of Mn ores can bring Hg into the surrounding aquatic environment through atmospheric deposition, leaching of electrolytic Mn residue and Mn gangue dump. However, limited is known that how these processes influence the environmental behaviors of Hg in waterbody. Therefore, the seasonal distribution and existing form of Hg in water and sediment in one Mn ore area in Xiushan County, Chongqing were investigated. Our results showed that the mean Hg and methylmercury(Me Hg) concentrations in water( n = 35) were 5.8 ± 4.6 ng/L and 0.22 ± 0.14 ng/L, respectively. The mean Hg concentrations in retained riverbed and fluvial bank sediment( n = 35) were 0.74 ± 0.26 mg/kg and 0.63 ± 0.27 mg/kg, respectively(the mean Me Hg concentrations were 0.64 ± 0.40 μg/kg and 0.51 ± 0.30 μg/kg, respectively). It indicated that the mining and smelting of Mn ores were the main sources of anthropogenic Hg, and Mn may inhibit Hg methylation in rivers in Mn ore areas. Mercury in the bound to iron/Mn(Fe/Mn) oxides of low crystallinity fraction(Hg-OX) accounted for 4.01% and 5.25% of the total Hg concentrations in the retained riverbed and fluvial bank sediment, respectively. The amount of Hg bound to Fe/Mn oxides in sediment increased significantly due to the manganese mining activities in the investigated area. Therefore, it could be hypothesized that high Hg concentrations in river sediment in Mn mining areas are closely related to high Mn concentration in sediment.

关键词： Mn mining area Hg MeHg Distribution characteristics Fractionation of Hg

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Role of the rhizosphere of a flooding-tolerant herb in promoting mercury methylation in water-level fluctuation zones

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Journal of Environmental Sciences 2022年第9期34卷 139-151页

作者： Juan wang Yuping Xiang Xiaosong Tian Cheng Zhang Guiqing Gong Jinping Xue Tao Jiang Dingyong wang yongmin wang Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin College of Resources and EnvironmentSouthwest UniversityChongqing 400715China Laboratory of Environmental Nanotechnology&Health Effect Chinese Academy of SciencesResearch Center for Eco-Environmental SciencesBeijing 100085China College of Resources and Safety Chongqing Vocational Institute of EngineeringChongqing 402260China Institut des Sciences Analytiques et des Physico-Chimie pour l’Environnement et les Materiaux(IPREM) UMR 5254CNRSUniversitede Pau et des Pays de l’AdourPau 64000France

The water-level fluctuation zone(WLFZ) has been considered as a hotspot for mercury(Hg) methylation. Flooding-tolerant herbs are gradually acclimated to this water-land ecotone, tending to form substantial root systems for improving erosion resistance. Accompanying rhizosphere microzone plays crucial but unclear roles in methylmercury(Me Hg) formation in the WLFZ. Thus, we conducted this study in the WLFZ of the Three Gorges Reservoir, to explore effects of the rhizosphere of a dominant flooding-tolerant herb(bermudagrass) on Me Hg production. The elevated Hg and Me Hg in rhizosphere soils suggest that the rhizosphere environment provides favorable conditions for Hg accumulation and methylation. The increased bioavailable Hg and microbial activity in the rhizosphere probably serve as important factors driving Me Hg formation in the presence of bermudagrass. Simultaneously, the rhizosphere environments changed the richness, diversity, and distribution of hgc A-containing microorganisms. Here, a typical ironreducing bacterium( Geobacteraceae) has been screened, however, the majority of hgc A genes detected in rhizosphere, near-, and non-rhizosphere soils of the WLFZ were unclassified. Collectively, these results provide new insights into the elevated Me Hg production as related to microbial processes in the rhizosphere of perennial herbs in the WLFZ, with general implications for Hg cycling in other ecosystems with water-level fluctuations.

关键词： Three Gorges Reservoir Water-level fluctuation zone Rhizosphere soil Methylmercury Mercury methylator

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The Proof and Application of a Summation Formula

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Advances in Pure Mathematics 2022年第9期12卷 541-559页

作者： yongmin wang Huimin Branch of Shandong Hengtai Engineering Group Co. Ltd. Binzhou China

In this paper, some conclusions related to the prime number theorem, such as the Mertens formula are improved by the improved Abelian summation formula, and some problems such as “Dirichlet” function and “W(n)” fu... 详细信息

关键词： Abel Summation Formula Mertens a Prime Number Theorem Dirichlet Function Conclusion Improvement

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Refining mercury emission estimations to the atmosphere from iron and steel production

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Journal of Environmental Sciences 2016年第5期28卷 1-3页

作者： yongmin wang Guangliang Liu Dingyong wang Yong Cai College of Resource and Environment Southwest University Institute of Environment and Health Jianghan University Department of Chemistry and Biochemistry Southeast Environmental Research Center Florida International University

Due to its long-range transport in the atmosphere,mercury is a pollutant of global concern with health risks to humans and ecosystems worldwide（Li et al.,2012;Lindqvist et al.,1991;Liu et al.,2012a;Tang et al.,2016;wang et al.,2015;Shao et al.,2016）.Atmospheric mercury,mainly from emission from various natural and anthropogenic sources and re-emission of previously released mercury built up in surface soils and oceans,

关键词： Mercury Emission Iron and steel production Anthropogenic sources

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Water level fluctuations influence microbial communities and mercury methylation in soils in the Three Gorges Reservoir,China

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Journal of Environmental Sciences 2018年第6期30卷 206-217页

作者： Yuping Xiang yongmin wang Cheng Zhang Hong Shen Dingyong wang College of Resources and Environment Southwest University Chongqing 400715 China Chongqing Engineering Research Center for Agricultural Non-point Source Pollution Control in the Three Gorges Reservoir Area Chongqing 400715 China Chongqing Key Laboratory of agricultural Resources and Environment Chongqing 400715 China

Reservoirs tend to have enhanced methylmercury（MeHg） concentrations compared to natural lakes and rivers, and water level fluctuations can promote MeHg production. Until now, little research has been conducted on the effects of microorganisms in soils for the formation of MeHg during different drying and flooding alternating conditions in the Three Gorges Reservoir（TGR）. This study aimed to understand how water level fluctuations affect soil microbial composition and mercury concentrations, and if such microbial variations are related to Hg methylation. The results showed that MeHg concentrations and the ratios of MeHg to THg（MeHg%） in soils were higher in the seasonally drying and flooding alternating areas（DFAs, 175–155 m） than those in the non-inundated（NIAs, 〉 175 m） and inundated areas（IAs, 〈 145 m）. However, MeHg% in all samples was less than 1%, indicating that the Hg methylation activity in the soils of the TGR was under a low level. 454 highthroughput sequencing of 16 S rRNA gene amplicons showed that soil bacterial abundance and diversity were relatively higher in DFA compared to those in NIA and IA, and microbial community composition varied in these three areas. At the family level, those groups in Deltaproteobacteria and Methanomicrobia that might have many Hg methylators were also showed a higher relative abundance in DFA, which might be the reason for the higher MeHg production in these areas. Overall, our results suggested that seasonally water level fluctuations can enhance the microbial abundance and diversity, as well as MeHg production in the TGR.

关键词： Water level fluctuation zone Three Gorges Reservoir Soil Microbial communities Methylmercury Methylators

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Mercury bioaccumulation in fish in an artificial lake used to carry out cage culture

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Journal of Environmental Sciences 2019年第4期31卷 352-359页

作者： yongmin wang Qing Xie Qinqin Xu Jinping Xue Cheng Zhang Dingyong wang College of Resources and Environment Southwest University Chongqing Key Laboratory of Agricultural Resources and Environment

As a global toxic pollutant,mercury(Hg)bioaccumulation within food chain could be influenced by human disturbance.Ten typical fish species were collected from Changshou Lake,an artificial lake used to carry out cage fish culture,to investigate the C/N isotopic compositions and Hg bioaccumulation in fish.The results showed that the total Hg(THg)and methylmercury(MeHg)levels in fish muscles((56.03±43.96)and(32.35±29.57)ng/g,wet weight),comparable with those in most studies in China,were significantly lower than the international marketing limit(0.5 mg/kg).Past human input for cage culture in this lake led to abnormal^(15)N enrichment in food chain,as the quantitative trophic levels based onδ^(15)N were different with that classified by feeding behaviors.This phenomenon subsequently demonstrated that it should be considered thoughtfully with respect to the application of the traditional method for understanding Hg bioaccumulation power by the slope of log_(10)[Hg]withδ^(15)N regression in specific water body(i.e.,Changshou Lake).In addition,no significant linear correlation between Hg and body weight or length of some fish species was observed,suggesting that the fish growth in the eutrophic environment was disproportionate with Hg bioaccumulation,and fish length or weight was not the main factor affecting Hg transfer with food web.The occurrence of human disturbance in aquatic system presents a challenge to a better understanding of the Hg bioaccumulation and biomagnification within the food chain.

关键词： Mercury Methylmercury Human disturbed lake Bioaccumulation N enrichment

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CFD-DEM-IBM方法探究流化床倾斜挡板内构件受力特性

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化工学报 2024年第1期75卷 255-267页

作者：赵碧丹代伊杨王军武张永民中国科学院过程工程研究所多相复杂系统国家重点实验室北京100190 中国科学院大学化学工程学院北京100049 中国石油大学(北京)重质油国家重点实验室北京102249

在密相床层内安装内构件可显著改善工业流化床的流化质量、强化气固传质和提高化学反应效率。由于长时间受气体和颗粒的挤压和冲击,流化床内构件可能会发生变形或断裂。为实现流化床内构件设计的科学性,确保其长周期可靠性,需要明确其... 详细信息

在密相床层内安装内构件可显著改善工业流化床的流化质量、强化气固传质和提高化学反应效率。由于长时间受气体和颗粒的挤压和冲击,流化床内构件可能会发生变形或断裂。为实现流化床内构件设计的科学性,确保其长周期可靠性,需要明确其受力机理与不同操作条件下受力特性。利用粗粒化CFD-DEM-IBM方法,实现了利用笛卡儿网格模拟流化床中倾斜挡板内构件受力特性的定量模拟,该方法拓展原有挡板应力统计方法,获得了不同倾斜角度对挡板所受应力的定量影响规律。模拟所得挡板受力随时间的演化曲线与实验报道较为一致,在流化床启动阶段会出现较大的峰值,同时成功复现在启动阶段的峰值受力总体与挡板在水平面上的投影面积成正比。模拟结果显示,在启动阶段,挡板受力中颗粒挤压作用力占主导,但在流化阶段,除颗粒作用力达到极大值外的大部分时间中挡板受到的气相压差力要大于颗粒作用力。当挡板倾斜角度较小时,挡板受力较大但抑制床内返混效果较好,因此在工业流化床内构件设计中应兼顾强化传递及长周期可靠性的需求,当挡板倾斜角度较小时应选择强度大的挡板材料。

关键词：气泡流化床数值模拟挡板内构件固相应力

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淮北平原中小型湖泊鸟类多维度多样性

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湖泊科学 2024年第4期36卷 1183-1191页

作者：李永民董锴李东伟王魏根胡文峰阜阳师范大学生物与食品工程学院阜阳236037 阜阳师范大学历史文化与旅游学院阜阳236037

湿地介于陆地和水生生态系统之间,具有丰富的生态价值,湿地公园在维持生态平衡,提高鸟类多样性等方面具有重要作用。2022年3月2023年2月,采用样点法和样线法对淮北平原地区颍州西湖国家湿地公园进行鸟类调查,通过对鸟类群落的物种多样... 详细信息

湿地介于陆地和水生生态系统之间,具有丰富的生态价值,湿地公园在维持生态平衡,提高鸟类多样性等方面具有重要作用。2022年3月2023年2月,采用样点法和样线法对淮北平原地区颍州西湖国家湿地公园进行鸟类调查,通过对鸟类群落的物种多样性、分类学多样性、功能多样性和系统发育多样性4个维度多样性指数以及鸟类生态类群的分析探究湿地公园鸟类群落的时空分布格局。本轮调查共记录鸟类153种共26107只次,其中国家Ⅰ级重点保护野生动物1种,国家Ⅱ级重点保护野生动物16种;IUCN红色名录极危物种1种,易危物种2种。结果表明:春季功能丰富度、物种丰富度和香农-威纳指数在湖泊、防护林和绿化带3种生境之间差异显著,夏季湖泊生境中物种丰富度(24.67±0.94)和系统发育多样性(985.14±52.57)显著高于绿化带和防护林,秋季功能丰富度(8.24±0.90)和系统发育多样性(935.34±37.12)在湖泊中均最高,冬季湖泊香农-威纳指数(2.31±0.03)、功能丰富度(3.73±0.77)显著高于绿化带和防护林2种生境;绿化带生境中,多个多样性指数在春季最高,在冬季均达到最低水平,湖泊生境冬季的物种丰富度(25.00±0.82)、香农-威纳指数和辛普森指数(0.84±0.01)在冬季最高,夏季系统发育多样性最高;防护林生境中物种丰富度(22.67±2.87)在秋季显著高于其他3个季节。单次调查中发现并记录青头潜鸭(Aythya baeri)15只,超过东亚-澳大利西亚候鸟迁徙路线该物种种群数量的1%,达到国际重要湿地标准。结果显示秋季为该湿地公园鸟类多样性保护的重点季节,湖泊生境为该湿地公园的重点保护区域,颍州西湖国家湿地公园对迁徙及越冬水鸟具有重要生态价值,应进一步加强鸟类监测,提升其生态功能。

关键词：淮北平原中小型湖泊鸟类多维度多样性时空格局

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Selective electrophilic di- and monofluorinations for the synthesis of 4-difluoromethyl and 4-fluoromethyl quinazolin(thi)ones by a Selectfluor-triggered multi-component reaction

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Organic Chemistry Frontiers 2022年第6期9卷 1567-1573页

作者： Ruiqin Zhang Renchao Ma Qinjiao Fu Rener Chen Zhiming wang Lei wang yongmin Ma Institute of Advanced Studies and School of Pharmaceutical and Chemical Engineering Taizhou UniversityJiaojiangZhejiang318000P.R.China School of Pharmaceutical Science Zhejiang Chinese Medical UniversityHangzhou310053P R China

A simple and efficient domino protocol for the selective synthesis of 4-difluoromethyl and 4-fluoromethylquinazolin(thi)ones was established from readily available 2-aminoacetophenones and iso(thio)cyanatesmediated by Selectfluor. The reaction outcomes are restricted by the reaction environment. Without theuse of a base, gem-difluoro-oxylated quinazolin(thi)ones were afforded effectively as a sole product. Incontrast, only monofluoro-oxylated analogues were obtained under basic conditions.

关键词： conditions product synthesis

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下睑眼袋内入路眶隔脂肪团取出处理后回填矫正泪沟及睑颊沟畸形的效果

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中华医学美学美容杂志 2024年第1期30卷 61-64页

作者：王咏民杜太超王涛金威北京黄寺医疗美容门诊部北京100066 北京丰科星范医疗美容门诊部北京100071 辽宁省辽阳市中心医院美容科辽阳111010

目的:探讨下睑眼袋内入路眶隔脂肪取出处理后回填矫正泪沟及睑颊沟畸形的效果。方法:2019年11月至2022年9月,北京黄寺医疗美容门诊部美容外科行下睑眼袋内入路眶隔脂肪团块取出后颗粒化处理,回填矫正泪沟及睑颊沟凹陷畸形患者42例,男13... 详细信息

目的:探讨下睑眼袋内入路眶隔脂肪取出处理后回填矫正泪沟及睑颊沟畸形的效果。方法:2019年11月至2022年9月,北京黄寺医疗美容门诊部美容外科行下睑眼袋内入路眶隔脂肪团块取出后颗粒化处理,回填矫正泪沟及睑颊沟凹陷畸形患者42例,男13例、女29例;年龄16~47(23.8±6.9)岁。患者均存在不同程度的眶隔脂肪膨出,轻、中、重度泪沟和睑颊沟凹陷畸形,下睑皮肤不松弛。经下睑结膜切口入路,将自然疝出的眶隔脂肪团剪除,颗粒化处理后装入1 ml注射器中,依据术前划线标记的凹陷区,精准填充至泪沟和睑颊沟凹陷的区域。术后随访3个月,观察手术效果及不良反应。结果:42例患者切口均一期愈合,无血肿感染;2例患者出现皮下瘀斑,48 h后局部热敷,1周瘀斑消退。分别在术后1、2、3个月随访,其中35例患者术后效果满意,眼袋膨出及睑颊沟、泪沟凹陷症状消失。7例眼袋伴泪沟及睑颊沟患者,由于眶隔脂肪量不足,还有轻微凹陷,术前已告知可能需要2次脂肪填充,1个月后于腿部取脂肪颗粒填充泪沟、睑颊沟凹陷,效果满意。结论:下睑内路眼袋眶隔脂肪团取出后处理并回填矫正泪沟及睑颊沟畸形的临床操作简单,手术后满意度高,值得临床应用。

关键词：眼睑下睑眼袋眶隔脂肪泪沟畸形

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