Petroleum waste biodegradation with porous biomass support system (PBSS) on rotating biological contactor

A laboratory scale study was conducted to assess the feasibility of the new coupling of rotating biological contactor (RBC) plus porous biomass support system (PBSS) using polyurethane foam as porous support media to biodegrade petroleum refinery wastewater. Polyurethane foam was attached on disks of two four-stage laboratory scale cascade connected RBC units.The two RBC units were operated simultaneously at different but constant, flowrates giving hydraulic loading rates of 0.01, 0.02, 0.03, 0.04 m3/m2/d in two runs keeping the same rotational speed 10 r/min throughout. Organic loading was a less controllable factor in this study.For all of the hydraulic loadings, it was found that the removal efficiency of total chemical oxygen demand (TCOD) and oil were above 80 percent. Ammonia nitrogen and phenol removal were above 90 and 80 percent respectively. The maximum biomass concentration within polyurethane foam was about 30 g/m2 in the first stage for 0.03 m3/m2/d hydraulic loading.The results show that t     

我国全氟辛烷磺酸盐分子毒理学研究进展：纪念金一和教授

全氟化合物(PFCs)在工业和生活中应用广泛,但是PFCs对生物体存在潜在的毒性,其中以8碳链的PFCs,如全氟辛烷磺酸(PFOS)和全氟辛烷羧酸(PFOA)应用最多。这类化合物在环境中很难降解,并能在生物体内富集^[1-6]。2009年PFOS被列入新增POPs名单,PFOS的毒性毒理研究随即成为研究热点。目前,国内研究者已陆续展开
PFOS对各种动物^[7-17],如昆虫、鸟类、鱼类、贝类、两栖类、哺乳类和人体细胞的急慢性毒性。但是这些关于PFOS毒性的研究所用剂量较高,远离了环境浓度范围,而高剂量的毒性效应与低剂量的毒性效应存在很大差异,尤其体现在不同剂量下作用的靶器官和信号通路的生物分子学响应会有很大差异。PFCs除了对肝脏造成慢性损伤、对免疫系统和生殖内分泌系统有明显影响外,还具有神经毒性。
已有的研究结果表明PFCs神经毒性潜在的机制主要有：影响神经元的生长分化、突触发生和脑发育;影响神经递质如多巴胺、谷氨酸和乙酰胆碱的水平;通过ROS诱导神经细胞凋亡;影响信号转导途径;影响甲状腺系统。在PFOS对神经系统毒性毒理方面,金一和教授课题组的研究工作十分系统。
金一和教授课题组针对PFOS对神经系统的影响,由浅入深地展开系列研究,提出了神经系统可能是PFOS的靶系统之一^[18-23]。针对外源性化合物易于蓄积和产生毒害的靶器官——海马结构,他们通过中枢神经系统兴奋性氨基酸和谷氨酰胺合成酶的剂量相应关系分析,提出了氨基酸类神经递质含量的改变是PFOS神经毒性的效应标记之一^[18-20]。这些研究在PFOS是如何干扰氨基酸类神经递质代谢,导致神经细胞损伤及神经功能损害方面给出了重要的线索。同时,他们通过对神经系统发育影响研究和基因组学手段,得出了PFOS会对后代学习记忆功能和脑的健康发育产生不良影响,并提出PFOS可能通过改变脑组织血氧平衡,影响中枢神经系统功能和发育过程的毒理学作用机制^[23-26]。
在PFOS对器官损伤机理方面,金一和教授课题组也做出了许多工作^[27-32]：提出PFOS的主要靶系统中还包括免疫系统,并用来解释PFOS染毒后,各脏器器官所呈现的功能下降的现象。
遗憾的是,金一和教授关于PFCs与生命系统相互作用机理的研究正在蒸蒸日上,他就离所热爱的事业而去。我们也只能以此文给金一和教授一生中最精彩的部分工作一个不完善的总结。金一和教授系统深入的研究成果为我国PFCs的分子毒理学研究奠定了坚实的基础,他颇具前瞻性的研究思想为后继者提供了启迪科研灵感的源泉。
     

Biosensors for pathogen surveillance

Biologists, chemists, and physicists are collaborating to develop highly sensitive and specific biosensors for pathogen detection in the food, healthcare, and environmental sectors. Those novel biosensors allow quick detection and are thus expected to solve the issues of the emergence of highly virulent or antibiotic-resistant pathogens. This article reviews different types of biosensors used for pathogen detection, classified based on the type of transducer used. Optical biosensors integrate labeled means, e.g., fluorophores, quantum dots, and carbon dots to overcome photobleaching. Surface plasmon resonance is also used for enhanced sensitivity. Mechanical biosensors with piezoelectric crystals and cantilevers are adapted for the detection of food pathogens without sample preparation or labels. Conventional methods using electrodes for the measurement of electrochemical changes with differential pulse voltammetry or impedance spectroscopy are fast and highly sensitive. Immunosensors are developed for pathogen detection at trace levels using sample enrichment, signal amplification, and new visual detection techniques.     

我国环境监测体制改革探讨

本文分析了目前我国环境监测工作中普遍存在的体制不顺、职责不明、行政干预、重复监测、资源浪费、信息混乱等问题,提出监测机构垂直管理,调整监测职能,打破条块分割,整合社会监测资源,引入第三方检测的具体构想。     

东亚古环境科学数据库

东亚古环境科学数据库依托于中国科学院地球环境研究所,是在原有古气候与古环境专题数据库基础上建立起来的国家地球系统科学数据共享平台的重要分支,在多个国家大型项目的支撑下,立足于中国大陆古环境研究领域,辐射东亚,通过集成、整合、引进等方式汇集国内外古环境研究领域科技数据资源,并进行规范化加工处理,分类存储,形成一个可提供快速共享服务的网络体系。数据库以黄土高原、青藏高原和内陆干旱区为重点,兼顾东亚其他地理单元,通过对现有古气候、古环境及相关实时观测资料的搜集、整理、数字化、集成、模拟以及二次挖掘,以正在进行的相关国家科研项目为基础,建成以中国大陆为中心的东亚区域的多源原始环境数据,古环境记录数字标本与代用指标,古气候与环境数值模拟结果等古环境科学数据集成与共享平台。     

Occurrence of pesticides and polychlorinated biphenyls in water of the Nile river at the estuaries of Rosetta and Damiatta branches,north of delta,Egypt

Abstract

A study was conducted from summer 1995 to summer 1997 to assess the seasonal occurrence of pesticide residues and other organic contaminants, polychlorinated biphenyls (PCBs), in water at the estuaries of Rosetta and Damiatta branches of the Nile river. The results indicated that organochlorine compounds (OCs) including HCB, lindane, p,p‘‐DDE, p,p‘DDD, p,p‘‐DDT, aroclor 1254 and aroclor 1260 were present in all the water samples at concentration levels ranging between 0.195–0.240, 0.286–0.352, 0.035–0.067, 0.019–0.033, 0.024–0.031, 0.390–0.70 and 0.166–0.330 μg/l, respectively. The levels of these compounds were higher in water of Damiatta branch than those found in water of Rosetta branch. Aldrin, dieldrin and endrin were not detected in all water samples. Only 4 compounds from 36 organophosphorus insecticides, fungicides and s‐triazine herbicides tested were detected in water samples collected during summer and autumn seasons from Rosetta branch. The concentration levels of these detected compounds, dimethoate, malathion, captan, and ametryne, ranged from 0.011 to 0.340 μg/l, respectively. Similar compounds during the same seasons as found in water of Rosetta branch were also detected in water of Damiatta branch except ametryne. The levels of the detected compounds (dimethoate, malathion and captan) ranged between 0.030 and 0.330 μg/l. The levels of detected organophosphorus insecticides, fungicides and s‐triazine herbicides were in the order: dimethoate > malathion > captan > ametryne.     

Seasonal activity of Bombus terrestris L. in east Mediterranean region, Turkey

Bumblebees have economical importance in most of wild and cultivated plants. They can be abundant in suitable habitats and have a broad flower choice. Bombus terrestris was collected at intervals during 2002 and 2003 from various flora and ecosystems of east Mediterranean region of Turkey. In this study, plants visited by Bombus terrestris, seasonal activities, distribution and altitudes were determined. Bombus terrestris have boon seen throughout Turkey in a wide range of habitats from sea level to 1560 m altitude within all the major native vegetation types. Prevalence of queens, workers and males of Bombus terrestris differed due to altitude. More frequently observed at 0-600 m, declining above 600 m in relation to general climate requirements.