Effect of benzo[a]pyrene on detoxification and the activity of antioxidant enzymes of marine microalgae

The objective of this study was to examine the effect of benzo[a]pyrene(Ba P) on the detoxification and antioxidant systems of two microalgae,Isochrysis zhanjiangensis and Platymonas subcordiformis.In our study,these two algae were exposed to Ba P for 4 days at three different concentrations including 0.5 μg~(L-1)(low),3 μg~(L-1)(mid) and 18 μg~(L-1)(high).The activity of detoxification enzymes,ethoxyresorufin O-deethylase(EROD) and glutathione S-transferase(GST) increased in P.subcordiformis in all Ba P-treated groups.In I.zhanjiangensis,the activity of these two enzymes increased at the beginning of exposure,and then decreased in the groups treated with mid-and high Ba P.The activity of antioxidant enzyme superoxide dismutase(SOD) increased in I.zhanjiangensis in all Ba P-treated groups,and then decreased in high Ba P-treated group,while no significant change was observed in P.subcordiformis.The activity of antioxidant enzyme catalase(CAT) increased in I.zhanjiangensis and P.subcordiformis in all Ba Ptreated groups.The content of malondialdehyde(MDA) in Isochrysis zhanjiangensis increased first,and then decreased in high Ba P-treated group,while no change occurred in P.subcordiformis.These results demonstrated that Ba P significantly influenced the activity of detoxifying and antioxidant enzymes in microalgae.The metabolic related enzymes(EROD,GST and CAT) may serve as sensitive biomarkers of measuring the contamination level of Ba P in marine water.     

New Zircon U‐Pb Age of Granodiorite in Chifeng at the Northern Margin of North China Craton and Constraints on Plate Tectonic Evolution

正Objective The North China Craton(NCC)is one of the oldest cratons in the world.The accretionary belt at its northern margin has been the focus of scholars both at home and abroad(Zhu Junbing and Ren Jishun,2017).In recent years,a series of Late Paleozoic–Mesozoic intrusions trending E–W have been discovered within the northern margin of the NCC,forming a magmatic belt.The study     

塔里木盆地西南坳陷齐姆根凸起侏罗系钻获油气显示

正1研究目的(Objective)研究区位于塔里木盆地塔西南坳陷齐姆根凸起英吉沙背斜构造单元西南。该区勘探程度低,此前未进行高覆盖次数地震勘探、无钻井,石油地质条件尚不清楚。本次研究的目的是落实英吉沙—莎车地区齐姆根凸起侏罗系杨叶组烃源岩有效性;厘清英吉沙—莎车地区地层发育情况,确定苏盖特构造侏罗系与周边露头剖面对比关系;获取钻井地质资料,为该区地震地质层位标定提供依据,了解区内的地层及储盖组合发育情况,为进一步油气勘探评价提供基础资料。     

湖北宜昌地区奥陶系五峰组-志留系龙马溪组获页岩气高产工业气流

正1研究目的(Objective)湖北宜昌王家湾是全球上奥陶统赫南特阶底界全球界线层型剖面所在地,也是世界上开展奥陶系和志留系界线对比研究的典型地区,具有很高的地层学研究水平。该地奥陶系五峰组—志留系龙马溪组下部以碳硅泥质页岩发育为特点,沉积连续,化石丰富,具有与中国已经建成的重庆涪陵焦石坝和长宁威远国家级页岩气勘探示范区页岩气勘探主力层系相似的地层和古生物发育特点。区域构造稳定,地层产状平缓,页岩气富集地质条件优越,但志留系页岩气的     

西藏“一江三河”地区地下水环境背景值初步研究

在分析对比国内外研究方法的基础上,选择数理统计方法,通过最广泛的数理统计法的应用原则、数据检验、背景值取值等问题的论述,对西藏"一江三河"地区地下水水质指标TDS,Ca²+,Mg²⁺,Na⁺环境背景值进行研究,并初步探讨了它们的空间分布规律及控制因素.结果表明,地形地貌、区域水动力条件等因素对研究区地下水指标的空间分布起主要控制作用.该结果为评价西藏"一江三河"地区地下水污染状况提供科学的依据.     

内蒙古赤峰地区早二叠世花岗岩LA-ICP-MS锆石U-Pb年龄及地球化学特征

以赤峰地区铭山复式岩体、尖山子岩体为研究对象,通过锆石U-Pb年龄、地球化学研究,确定了其形成时代,探讨了岩石成因和岩浆源区性质及其形成的构造背景。LA-ICP-MS锆石~(206)Pb/~(238)U测年结果表明,铭山复式岩体中灰白色斑状黑云二长花岗岩、尖山子岩体中浅肉红色细粒正长花岗岩分别形成于284.4±7.9Ma、294.7±8.5Ma,为早二叠世。根据地质体间接触关系可知,铭山复式岩体中的二长花岗岩岩体和尖山子岩体均为复式岩体,有待进一步解体。斑状黑云二长花岗岩SiO_2含量较高,K_2O+Na_2O含量较高,A/CNK1,属于高钾钙碱性I型花岗岩。细粒正长花岗岩Al_2O_3含量为14.32%~15.14%,Na_2O/K_2O=0.71~0.99,A/CNK=1.17~1.20,在标准矿物中出现刚玉分子。二者微量元素特征相似,富集大离子亲石元素,亏损高场强元素Nb、Ta,具Sr、P、Ti的负异常,表现出岛弧岩浆岩类特征。结合岩石地球化学、区域地质特征,认为赤峰地区早二叠世岩体形成于岛弧/活动大陆边缘构造背景,其形成与古亚洲洋向南俯冲有关。     

Characterizing groundwater/surface-water interactions in the interior of Jianghan Plain,central China

Hydrogeology Journal - Quantifying groundwater/surface-water interactions is essential for managing water resources and revealing contaminant fate. There has been little concern on the exchange...     

辽西北票(金-羊)盆地北票组层序地层及沉积体系特征

为揭示北票(金-羊)盆地内北票组层序地层特征及沉积体系分布规律,应用层序地层学及沉积学理论和方法,综合利用野外露头、剖面等资料,建立了北票(金-羊)盆地北票组的层序地层格架,确定研究区的沉积相类型及分布规律。研究结果表明,北票(金-羊)盆地北票组可划分为2个三级层序,其内部可进一步划分为7个准层序组。在层序内识别出冲积扇、辫状河三角洲、湖泊3个沉积相。明确了沉积相的分布规律,向上形成由冲积扇到辫状河三角洲,再到湖相,最后是辫状河三角洲的沉积体系;平面上呈近北西—南东向展布的沉积体系,整体构成2个水进、水退的沉积体系。古地貌影响了底部冲积扇相沉积物的沉积特征。气候不仅影响了沉积物类型,且和湖平面变化共同控制了沉积物的演化规律。     

层次分析与模糊数学综合评价法在矿山环境评价中的应用

采用遥感技术提取矿山环境评价因子,运用层次分析法与模糊数学法对三江成矿带南段矿山环境进行综合评价。层次分析法确定的矿山环境评价因子按权重排序,依次为植被覆盖率、土地利用、地形地貌、矿山地质灾害、水土流失和矿山开发占地;模糊数学法评价的区域矿山环境隶属第一等级"好"。通过GIS平台,按权重值对评价因子进行叠加、成图,实现了三江成矿带南段的矿山环境评价。层次分析与模糊数学综合评价法,不仅综合考虑矿山环境影响因子,且充分发挥了2种数学方法的优点,将动态与静态、定量与非定量等指标有机结合,发挥其因素和过程的模糊性,减少了专家人为评分的主观性,使评价结果更符合实际。