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Source emissions and climate change impacts on the multimedia transport and fate of persistent organic pollutants,Chaohu watershed,eastern China

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Journal of Environmental Sciences 2021年第11期33卷 15-25页

作者： Xianghui Cao Shouliang Huo Hanxiao Zhang Jiaqi Zheng Zhuoshi He Chunzi ma Shuai Song State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental ScienceBeijing 100012China Beijing Normal University Beijing 100874China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Emission intensity and climate change control the transport flux and fate of persistent organic pollutants(POPs)inmultiple environmental *** study applied amultimedia model(BETR model)to explore alternations in the spatio-temporal trends of concentrations and transport flux of benzopyrene(baP),phenanthrene(Phe),perfluorooctane sulfonates(PFOS)and polychlorinated biphenyls(PCBs)in the Chaohu watershed,located in the lower reaches of the Yangtze River,China in response to changes in source emissions and *** potential historic and future risks of these pollutants also were *** results suggest that current trends in concentrations and transport were similar to that of their emissions between 2005 and *** the next 100 years,temporal trends and spatial patterns were not predicted to change significantly,which is consistent with climate *** on sensitivity and correlation analyses,climate change had significant effects on multi-media concentrations and transport fluxes of baP,Phe,PFOS and PCBs,and rainfall intensity was the predominant controlling *** quotients(RQs)of baP and Phe-in soil increased from 0.42 to 0.95 and 0.06 to 0.35,respectively,from 2005 to 2090,indicating potential *** RQs of the other examined contaminants exhibited little potential risk in soil,water,or *** on spatial patterns,it was inferred that the ecosystem around Lake Chaohu is the most at *** study provides insights needed for local pollution control of POPs in the Chaohu *** addition,the developed approach can be applied to other watersheds world-wide.

关键词： Climate change POP emissions Multimedia model Contaminant transport Risk assessment

Synthetic Features and Mechanism for the Preparation of Vinyl Chloride-co-Butyl Acrylate-co-Vinyl Acetate Terpolymer via Precipitation Polymerization

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Chinese Journal of Polymer Science 2023年第11期41卷 1714-1724,I0006页

作者： Chang-Tong Song Xian-Hong Zhang Dong Chen Yu-Hong ma Wan-Tai Yang State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China College of material Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China

Without any type of su rfactant or dispersing agent,precipitation polymerization has great superiorities in both polymer synthesis and *** the present work,the polymerization of vinyl chloride(VC),n-butyl acrylate(ba),and vinyl acetate(VAc)are conducted in the precipitation polymerization system and series of their random terpolymers poly(vinyl chloride-co-n-butyl acrylate-co-vinyl acetate)(PCBV)are synthesized *** effects of various polymerization conditions,including solvent polarity,temperature,initiator concentration,and monomer feed ratios on the polymerization kinetics,number-average molecular weight(M_(n)),and terpolymer composition are investigated *** solvent and the monomer feed ratio are crucial factors not only for the polymer morphology,but also for the reaction *** the non-polar solvent such as n-hexane,the PCBV displays particle morphology when the composition of ba ratio lower than 10 wt%.Otherwise,the PCBV forms a uniform polymer phase and precipitates out from the *** the polar solvent,e.g.,dimethyl carbonate(DMC)and ethanol,the PCBV polymer maintains a slurry state either in low or in high monomer feed ***,VC based ternary copolymer that obtained in n-hexane has much lower M_(n)(igher ba units mass fraction(>40 wt%)compared with emulsion and suspension ***,the terpolymer can be easily sepa rated by simple centrifugation.

关键词： Precipitation polymerization Copolymerization Vinyl chloride Low molecular weight

MiF和NF-κB及iL-1β在鼻息肉组织中的表达及意义

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临床耳鼻咽喉头颈外科杂志 2016年第3期30卷 220-225页

作者：李春苗马辉娟巴云鹏郑州大学第一附属医院鼻科郑州450052

目的:通过检测巨噬细胞移动抑制因子(MiF)、核转录因子-κB(NF-κB)、iL-1β在鼻息肉组织及正常下鼻甲组织中的表达,并分析三者的相关性,探讨其在鼻息肉中的作用,并分析可能的作用机制。方法:应用苏木精-伊红染色方法分析48例鼻息肉患者... 详细信息

目的:通过检测巨噬细胞移动抑制因子(MiF)、核转录因子-κB(NF-κB)、iL-1β在鼻息肉组织及正常下鼻甲组织中的表达,并分析三者的相关性,探讨其在鼻息肉中的作用,并分析可能的作用机制。方法:应用苏木精-伊红染色方法分析48例鼻息肉患者(鼻息肉组)EOS等炎性细胞浸润的情况;采取免疫组织化学法检测MiF、NF-κB p65及iL-1β的表达及分布,以21例鼻中隔矫正术中下鼻甲黏膜为对照组;应用VAS、Lund-Kennedy方法对鼻息肉组进行病情分析,并对鼻息肉病情严重程度与MiF、NF-κB p65及iL-1β的表达水平进行相关性分析。结果:1鼻息肉组的EOS浸润程度、MiF、NF-κB p65、iL-1β水平均明显高于对照组(均PiF、NF-κB p65、iL-1β之间呈正相关(r分别为0.74、0.66、0.60,均PiF、iL-1β均存在显著正相关性(r分别为0.67、0.63,均PiF、iL-1β存在正相关(r分别为0.49、0.55,P0.05);2鼻息肉组VAS评分为8.24±1.72,鼻内镜检查评分为8.63±3.81。Spearman相关性分析显示,VAS评分与MiF水平呈正相关(r=0.71,PiL-1β均无明显相关性(P>0.05);鼻内镜检查评分与MiF及NF-κB p65核染阳性率呈正相关(r分别为0.79、0.73,PiL-1β水平无明显相关性(P>0.05)。结论:MiF、NF-κB p65及iL-1β可能通过协同作用促进鼻息肉的发生发展,鼻息肉中可能存在有iL-1β-NF-κB-MiF途径;MiF与NF-κB p65可能参与维持下鼻甲的生理功能或与下鼻甲最轻持续炎症反应有关系,MiF及NF-κB p65核染阳性率在一定程度上可作为判断鼻息肉严重程度及预后的一个标准。

关键词：鼻息肉巨噬细胞移动抑制因子核转录因子-κB 白介素-1β

黔东地区寒武系纽芬兰统黑色岩系沉积特征及V多金属的富集机制

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矿物学报 2025年第6期44卷 763-781页

作者：谯文浪杨瑞东付勇倪莘然陈武季国松马义波贵州大学资源与环境工程学院贵州贵阳 550025 贵州省地矿局一〇二地质大队贵州遵义 563000 贵州省地质调查院贵州贵阳 550081

早寒武世贵州普遍沉积了一套黑色页岩，但其沉积相存在明显差异。凯里−三都地区总体为盆地相至斜坡相的寒武系纽芬兰统黑色岩系是区内V多金属元素的重要产出层位。本文选取贵州凯里−三都地区寒武系纽芬兰统典型黑色页岩剖面，对含V岩系... 详细信息

早寒武世贵州普遍沉积了一套黑色页岩，但其沉积相存在明显差异。凯里−三都地区总体为盆地相至斜坡相的寒武系纽芬兰统黑色岩系是区内V多金属元素的重要产出层位。本文选取贵州凯里−三都地区寒武系纽芬兰统典型黑色页岩剖面，对含V岩系展布规律和沉积特征进行综合调查研究。分析测试V及其相关元素的含量以揭示V元素的空间分布规律及其地球化学特征。结果表明，V从北往南富集程度呈降低趋势，垂向从下往上呈降低趋势。Al/(Al+Fe+Mn)值、Y/Ho值及Sm/Nd-Eu/Sm值等地球化学特征，指示该区沉积时的物源是以陆源为主；SiO 2/Al2O3、Eu/Eu*值、w(SiO2)- w(K2O+Na2 O)以及不同沉积物中Fe、Mn和微量元素Ni、Co含量等，指示研究区内存在热水沉积作用；Mo、ba、U等元素富集系数均值，Co、Sr、Ce异常特征，Th/U、Ni/Co和V/Cr值等指示研究区内含V岩石沉积环境趋向于缺氧（还原）环境-弱氧化环境，寒武纪区域古地理演化影响了黑色页岩中V的富集。

关键词： V多金属黑色岩系富集规律寒武系纽芬兰统黔东

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中频非平衡磁控溅射制备Ti-N-C膜

东北大学学报（自然科学版） 2008年第7期29卷 1049-1052页

作者：张以忱巴德纯颜云辉马胜歌东北大学机械工程与自动化学院辽宁沈阳110004 深圳国家863计划材料表面工程技术研究开发中心广东深圳518029

采用霍尔离子源辅助中频非平衡磁控溅射技术,通过改变工作气氛、偏压模式、溅射电流以及辅助离子束电流,在不锈钢材料基体上制备了Ti/TiN/Ti(C,N)硬质耐磨损膜层.对薄膜的颜色、晶体结构、膜基结合力等性能进行了检测分析.结果表明:膜... 详细信息

采用霍尔离子源辅助中频非平衡磁控溅射技术,通过改变工作气氛、偏压模式、溅射电流以及辅助离子束电流,在不锈钢材料基体上制备了Ti/TiN/Ti(C,N)硬质耐磨损膜层.对薄膜的颜色、晶体结构、膜基结合力等性能进行了检测分析.结果表明:膜层的颜色对工作气氛非常敏感,反应溅射中工作气氛的微小变化会引起表面膜层颜色很大的变化.在正常的反应气体进气量范围内和较小的基体偏压下,薄膜的晶体结构没有明显的择优取向.但是反应气体的过量通入会使薄膜的晶体结构出现晶面择优取向趋势.非平衡磁控溅射成膜技术对薄膜晶体结构的择优取向影响并不是很大.在镀膜过程中施加霍尔电流,可以有效地增加膜基结合力.

关键词： Ti—N—C薄膜非平衡磁控溅射中频溅射靶晶体结构离子束辅助沉积

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镁合金表面水滑石膜耐蚀性研究进展

材料导报 2017年第11期31卷 144-150,157页

作者：巴志新陈永俊董强胜马彪吕小雨南京工程学院材料工程学院南京211167 江苏省先进结构材料与应用技术重点实验室南京211167

镁合金由于具有优异的性能受到研究者的关注和重视,但易腐蚀的特性严重制约了其工程应用,故需采取合适的手段增强其耐蚀性。水滑石膜具有良好的离子交换性及物理屏障作用,近年来在镁合金表面改性方面逐步得到发展。介绍了多种镁合金表... 详细信息

镁合金由于具有优异的性能受到研究者的关注和重视,但易腐蚀的特性严重制约了其工程应用,故需采取合适的手段增强其耐蚀性。水滑石膜具有良好的离子交换性及物理屏障作用,近年来在镁合金表面改性方面逐步得到发展。介绍了多种镁合金表面水滑石膜层的制备工艺及其成膜原理,初步探讨了其在腐蚀环境下的耐蚀机制,并详述了几种进一步提高水滑石膜质量的改性方法及原理,展望了未来研究的工作重点和发展方向。

关键词：镁合金水滑石膜耐蚀机理表面改性

Frequency of Cardiovascular Risk Factors in Systemic Lupus Erythematosus: A Case-Control Study in a Department of internal Medicine in Sub-Saharan Africa

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Open Journal of internal Medicine 2020年第1期10卷 1-12页

作者： ma&iuml mouna Sow ba&iuml dy Sy Kane Abdourahmane Samba Awa Cheikh Ndao Nafissatou Diagne Boundia Djiba Mouhamed Dieng Atoumane Faye Abdoulaye Pouye internal Medicine Department Aristide Le Dantec Teaching Hospital Dakar Senegal Biochemistry Department Aristide Le Dantec Teaching Hospital Dakar Senegal

background: The morbidity and mortality of systemic lupus erythematosus are largely due to accelerated atherosclerosis. This is partly related to the high prevalence of traditional cardiovascular risk factors. The aim of our study was to determine the frequency of these factors in lupus patients compared to a control population in a department of internal medicine. Methods: We realized a case-control study in patients with systemic lupus erythematosus according to ACR criteria in 1997. Patients were matched by age and gender with controls subjects without autoimmune disease. We studied the frequency of traditional cardiovascular risk factors in both populations. The study was done in the department of internal medicine of Aristide Le Dantec teaching Hospital, in Senegal, during the period from August 2017 to December 2018. The statistical analysis was performed with SPSS 23.0 software and the level of significance was retained for a p-value Results: We recruited 100 subjects including 50 patients and 50 controls. The mean age was 33.5 ± 11.3 years in cases and 33.3 ± 11.3 years in controls. Dyslipidemia was significantly associated with systemic lupus erythematosus (p = 0.009). Levels of triglycerides (p Conclusion: Traditional cardiovascular risk factors including dyslipidemia and hyperuricemia were more common in patients. Similarly, renal failure was associated with lupus.

关键词： Cardiovascular Risk Factors Systemic Lupus Erythematosus Sub-Saharan Africa

开放式低温等离子体对树脂基复合材料表面处理性能研究

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表面技术 2023年第6期52卷 420-428页

作者：巴德玛乔乾森李长青崔海超陆军装甲兵学院装备保障与再制造系北京100072 中国人民解放军32178部队北京100012 中航工业复合材料技术中心北京101300

目的采用开放式低温等离子体对树脂基复合材料表面处理,研究其对树脂基复合材料粘接性能的影响。方法运用响应曲面法,对开放式低温等离子体加工工艺与树脂基复合材料表面自由能交互性进行研究。采用接触角测量仪、扫描电子显微镜(SEM)... 详细信息

目的采用开放式低温等离子体对树脂基复合材料表面处理,研究其对树脂基复合材料粘接性能的影响。方法运用响应曲面法,对开放式低温等离子体加工工艺与树脂基复合材料表面自由能交互性进行研究。采用接触角测量仪、扫描电子显微镜(SEM)、三维形貌仪、X射线光电子能谱仪(XPS)、傅里叶红外光谱仪(FT-iR)等仪器对开放式低温等离子体处理前后复合材料的接触角与表面能、表面微观形貌与表面粗糙度、表面化学成分进行分析,使用万能试验机对处理前后复合材料的粘接强度进行研究。结果输入功率、喷枪距离与试样移动速度3个响应因子中,喷枪距离对试样表面能的影响最为显著,其次是试样移动速度与输入功率。当开放式低温等离子体加工工艺为P=800 W,d=11.8 mm,v=10 mm/s时,表面能最大,从24.8 mJ/m^(2)增加到78.3 mJ/m^(2),表面粗糙度与未处理试样相比提高了约2.5倍。处理后试样表面的氧元素含量明显增加,氧元素主要以含氧官能团的形式存在,材料表面极性增加。开放式低温等离子体对树脂基复合材料处理后,粘接试样平均拉伸剪切强度从16.6 MPa增加到27.5 MPa,粘接强度提高了约65.7%,粘接接头破坏形式从界面破坏到材料基材破坏。结论开放式低温等离子体对树脂基复合材料表面处理后,能够有效地增加其粘接强度,树脂基复合材料润湿性与表面能、表面粗糙度以及表面含氧官能团数量增加,是粘接强度提高的主要因素。

关键词：树脂基复合材料开放式低温等离子体微观形貌表面能粘接性能

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Empty Sella Turcica Syndrome: About a Case Revealed by Adrenal insufficiency

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Open Journal of internal Medicine 2021年第2期11卷 68-72页

作者： Sow maïmouna Diagne Nafissatou Ndao Awa Cheikh Thiam Mbaye Faye Atoumane Dieng Mouhamed Kane baïdy Sy Djiba Boundia Pouye Abdoulaye internal Medicine Department Aristide Le Dantec Teaching Hospital Dakar Senegal Radiology Department FANN Teaching Hospital Dakar Senegal

background: Empty sella turcica corresponds to an arachnocele which may be complete or partial, primary or secondary. The primary form is rarer. its cause is unknown, but etiological factors have been identified. The prevalence of this condition is variable, depending on techniques of diagnosis. it may be detected fortuitously on imaging or in the presence of neurological, ocular or endocrine manifestations. Aim: We aim to report a case of empty sella turcica syndrome revealed by adrenal insufficiency in a young African black woman. Case presentation: it was an overweight young woman with signs of intracranial hypertension associated with central adrenal insufficiency. The diagnosis of empty sella was confirmed by magnetic resonance imaging. Secondarily, she developed a hypo metabolism syndrome and biology confirmed central hypothyroidism. After correction of the adrenal cortical deficit, the treatment of the thyroid deficit was administered. Evolution was favourable clinically and biologically. Conclusion: The empty sella turcica is rare and its revelation by a central adrenal insufficiency is even more. The case we report is a perfect illustration.

关键词： Empty Sella Turcica Adrenal insufficiency intracranial Hypertension