黑碳对沉积物和土壤中乙草胺吸附作用

黑碳是自然界普遍存在的物质,它对持久性污染物的迁移转化有重要影响.研究了沉积物和土壤中的黑碳在农药乙草胺吸附行为中的作用.结果表明:乙草胺在黑碳上的初始吸附符合一级动力学模型.在黑碳与有机碳相对含量较低(fBC/fOC=0.02～0.09)时,非黑碳的有机碳对吸附起主要作用.在黑碳与有机碳的相对含量较高(0.30～0.61)时,黑碳对吸附起主导作用,黑碳相对含量越高,对KOC影响越大.同时,建立了乙草胺吸附体系中KOC与fBC之间的关系模型用于预测不同黑碳含量的天然吸附剂对乙草胺的吸附能力.     

黑碳气溶胶研究新进展

黑碳气溶胶是气溶胶的重要组成部分,在大气物理、大气化学、大气光学、大气光化学等过程中具有重要作用。近年来研究表明,黑碳气溶胶对于全球变暖、区域气候变化有重要贡献,黑碳气溶胶可能是影响全球变暖的第二大重要因子,其作用仅次于CO2。因此,应控制黑碳的排放。考虑到黑碳气溶胶在全球变暖、区域气候、环境与健康等方面的作用,研究和评价黑碳气溶胶的作用已十分必要和迫切。     

线性等温吸附条件下有机污染物在地下饱水带中迁移的数学模型及参数分析

为研究在固-液界面的吸附降解等行为对饱水带中的有机污染物的迁移转化过程的影响,综合考虑有机污染物在饱水带中的扩散、吸附解吸、分配以及微生物降解作用,根据线性等温平衡吸附理论,建立了地下水流动方程与有机污染物在饱水带中迁移方程耦合的数学模型,探讨了模型中的分配系数及溶解项、吸附项的一阶反应速率等参数的改变对有机污染物运移规律的影响.结果表明,随着分配系数的增大,有机污染物因固相介质的吸附和截留而被限制其随地下水迁移;微生物降解作用对有机污染物的浓度有重要影响,随着反应速率的改变,污染物在固相和水相中的浓度迅速改变.本文的研究结果为定量描述溶质迁移过程提供理论依据,同时也为实验室中模型参数的测定提供可靠的依据.     

环境多介质模型构建方法与应用

环境多介质模型可用于综合描述化合物在实际环境中的分配和迁移过程,预测污染物在多介质环境中的归趋,是环境风险评价的有效工具。介绍了环境多介质模型的类型,概述了环境多介质模型的结构和建模方法,进一步展望了其应用前景和发展趋势。随着环境多介质模型向更加综合、广泛和通用的方向发展,未来将能更加强化和突出其在预测污染物残留、了解环境容量和制定环境标准等方面的重要作用。     

大气中持久性有机污染物(POPs)研究进展

持久性有机污染物(POPs)是环境中严格控制的一类高毒、易环境迁移的污染物,大气是POPs的一种重要载体和传输介质,该文讨论了大气中POPs的来源、采样技术发展趋势、区域分布特征以及影响因素,提出大气POPs的研究中存在的主要问题及研究趋势.     

水稻田土壤及其提取物对腐殖酸和芘的吸附性能

分析了青紫泥和黄筋泥两种不同地区的水稻田土壤及其提取物对亲水性有机物腐殖酸和疏水性有机污染物芘的吸附性能,得出以下实验结果：水稻土壤类型对腐殖酸或芘的吸附持留能力无显著影响;土壤及其提取物对腐殖酸的吸附性能强弱依次为原土>黑碳>无机矿物;对芘的吸附性能原土和黑碳比较接近,Freundlich方程及其吸附解吸分配系数（Kf）能更好地反映出二者对芘的吸附性能;水稻土壤及其黑碳的亲水/疏水性能是二者对腐殖酸和芘吸附性能强弱的主要决定因素.     

含S,N,O-杂环的难降解有毒有机污染物微生物降解机理和技术研究取得重要进展

在国家自然科学基金的连续资助下,山东大学微生物技术国家重点实验室许平教授及其合作者系统深入地研究了环境中含S,N,O-杂环的有毒难降解有机污染物的微生物降解机理和技术．通过5年多的积累,在化石燃料生物脱有机硫、含S,N,O-杂环的有毒难降解有机污染物的微生物降解和杂环联合降解的基因工程菌的构建等方面取得了系列重要成果．2005—2006年在环境和环境微生物领域国际上最有影响的两大     

环境中的邻苯二甲酸酯

通过检索国内外相关文献资料,重点阐述和归纳了邻苯二甲酸酯在生态毒性、来源、环境化学行为及污染现状方面的研究进展。结果表明,邻苯二甲酸酯是一类具有环境内分泌干扰作用的有机污染物,主要来源于人工合成,可通过各种途径进入环境,广泛存在于大气、水体、土壤、沉积物、灰尘等环境介质中,日用消费品中也普遍含有。邻苯二甲酸酯的大量使用所带来的环境污染和人体健康问题应当引起足够重视。     

污泥中多环芳烃分析方法

多环芳烃（PAHs）是一类广泛存在于环境中的有机污染物,具有致癌、致畸和致突变作用,难降解,易在生物体内积累,在大气和水体中较为广布。目前,世界各地各种环境介质都普遍受到了PAHs污染,因此对污水处理过程中污泥中的PAHs污染物的分析具有重要意义。     

水体介质中有机农药降解的研究进展

由于有机农药的过量施用使其成为水体介质中的重要污染物之一,对人类健康及环境构成了严重的威胁,因此水体中有机农药的降解备受关注,并且成为研究热点之一.本文分别对水体中的有机农药的生物降解、物理降解和化学降解等方面的研究进展进行综述,重点介绍了高级氧化技术中的光催化技术在农药降解领域的应用,概述了二氧化钛和溴氧化铋对有机农药光催化降解的基本原理,并展望了有机农药光催化降解研究趋势.     

Reburial of fossil organic carbon in marine sediments

Marine sediments act as the ultimate sink for organic carbon, sequestering otherwise rapidly cycling carbon for geologic timescales. Sedimentary organic carbon burial appears to be controlled by oxygen exposure time in situ, and much research has focused on understanding the mechanisms of preservation of organic carbon. In this context, combustion-derived black carbon has received attention as a form of refractory organic carbon that may be preferentially preserved in soils and sediments. However, little is understood about the environmental roles, transport and distribution of black carbon. Here we apply isotopic analyses to graphitic black carbon samples isolated from pre-industrial marine and terrestrial sediments. We find that this material is terrestrially derived and almost entirely depleted of radiocarbon, suggesting that it is graphite weathered from rocks, rather than a combustion product. The widespread presence of fossil graphitic black carbon in sediments has therefore probably led to significant overestimates of burial of combustion-derived black carbon in marine sediments. It could be responsible for biasing radiocarbon dating of sedimentary organic carbon, and also reveals a closed loop in the carbon cycle. Depending on its susceptibility to oxidation, this recycled carbon may be locked away from the biologically mediated carbon cycle for many geologic cycles.     

沙尘天气对内蒙古草原城市大气环境质量的影响研究

沙尘不仅是生态环境恶化的重要标志,也会污染大气环境,影响气象、气候和人体健康。为了探讨沙尘天气对内蒙古草原城市大气环境的影响,综合利用遥感影像与地面观测数据,研究了沙尘天气对锡林郭勒盟草原城市大气环境质量的影响,以期为沙尘天气环境影响评价提供理论依据。研究表明利用MODIS(the moderate resolution imaging spectroradiometer)数据可以实现沙尘活动的遥感监测,结果与基于地面观测发生规律一致;并得到气溶胶自动观测网(aerosol robotic network,AERONET)AOD(aerosol optical depth)产品验证。沙尘天气引起草原城市能见度下降,空气环境质量下降。大气污染主要由颗粒物的增加引起;但伴随沙尘天气的大风使CO、NO_2、SO_2等污染物浓度下降,具有清除人为源所排放污染物作用。     

To Improve the Dispersibility of Carbon Black in Water with Plasma and Organic Amines Treatments

Carbon black has been widely used in many industrial areas,but it is poor dispersibility in water. In order to improve its dispersibility in water,carbon black was treated by oxygen plasma. Plasma treatment,as one of the environmental friendly methods,has been used to introduce polar groups,mainly oxygen-containing groups,to the surface of carbon black. The results show the dispersibility of treated carbon black in water is greatly improved,which is expressed with the centrifugal and gravity settlement rates. Analysis of the treated carbon black with X-ray photoelectron spectroscopy (XPS) indicates that oxygen plasma treatment can cause significant increase of polar groups including C-OH,COOH,C=O,and O-C-O on the surface of carbon black thus greatly improves the dispersing stability of carbon black in water. Besides,the dispersibility of plasma treated carbon black can be further improved by the addition of organic amines,especially polyetheramines. The improvement of the dispersing stability of carbon black has also been confirmed by zeta potential measurements.     

我国含氯农药污染现状研究进展

研究分析了我国近年来(1990-2005)有机氯农药在空气、土壤、水体、食品和人体中的残留水平及分布特征,为政府部门评价持久有机氯农药对我国环境污染状况以及开展污染物区域治理提供决策依据。     

卤氧化铋光催化去除环境污染物

卤氧化铋基半导体材料具有铋氧层和卤素层交替排布的独特层状结构和易调节的禁带宽度,在直接利用太阳光去除环境污染物方面表现出优异性能和巨大潜力.基于国内外相关研究进展及本课题组近年来的研究成果,该文综述了卤氧化铋材料(氯氧化铋、溴氧化铋和碘氧化铋)光催化去除环境污染物方面的研究成果,主要包括卤氧化铋光催化材料的设计和改性策略,以及上述新材料在重金属离子去除、有机污染物降解和空气净化等领域的研究进展.最后,提出了卤氧化铋光催化材料在环境污染控制领域的研究展望.     

Recent Northern Hemisphere tropical expansion primarily driven by black carbon and tropospheric ozone

Observational analyses have shown the width of the tropical belt increasing in recent decades as the world has warmed. This expansion is important because it is associated with shifts in large-scale atmospheric circulation and major climate zones. Although recent studies have attributed tropical expansion in the Southern Hemisphere to ozone depletion, the drivers of Northern Hemisphere expansion are not well known and the expansion has not so far been reproduced by climate models. Here we use a climate model with detailed aerosol physics to show that increases in heterogeneous warming agents--including black carbon aerosols and tropospheric ozone--are noticeably better than greenhouse gases at driving expansion, and can account for the observed summertime maximum in tropical expansion. Mechanistically, atmospheric heating from black carbon and tropospheric ozone has occurred at the mid-latitudes, generating a poleward shift of the tropospheric jet, thereby relocating the main division between tropical and temperate air masses. Although we still underestimate tropical expansion, the true aerosol forcing is poorly known and could also be underestimated. Thus, although the insensitivity of models needs further investigation, black carbon and tropospheric ozone, both of which are strongly influenced by human activities, are the most likely causes of observed Northern Hemisphere tropical expansion.     

天气和气候条件对大气PM2.5和臭氧污染形成过程的影响

 在大气污染过程中，化学物质排放是内因，气象条件是外因，影响着污染物的传输扩散、化学转化、干湿沉降等过程。综述了中国近几年关于天气和气候条件对PM_2.5和臭氧污染形成过程影响的研究进展和相关领域未来研究的重点。结果发现，目前关于天气和气候条件影响PM_2.5的研究较为系统，能识别气候因子、区域环流、局地静稳天气的配置关系，但对天气和气候影响臭氧污染的研究还较少。     

红松木烧碱法制浆黑液中木质素对污染负荷影响

为研究蒸煮黑液中木质素对污染负荷影响,研究了红松木片化学浆蒸煮黑液的污染特性及特征污染物,通过紫外-可见光谱法建立了快速测定液相木质素的分析方法及木质素对COD贡献的工作曲线,探究黑液中木质素对总COD污染负荷的贡献.结果表明蒸煮过程中,黑液中含有较高浓度的溶解态有机物,可生化处理性差,成分复杂,主要有机污染物为酚类和有机酸类物质,其中酚类化合物的相对含量高达84.34%;经测定黑液中木质素浓度为65.7g·L~(-1),产生COD_(cr)值高达93 640.86mg·L~(-1),占黑液总CODcr含量的51%左右,黑液中木质素对黑液废液污染有较大的贡献.     

化工企业污染物影子价格的估计 ——基于参数化的方向性距离函数

以化工行业为例,利用参数化的方向性距离函数估算2007—2012年867家化工企业两种空气污染物(二氧化硫和氮氧化物)和二氧化碳的影子价格,衡量污染的边际减排成本,得到如下结果:1)样本化工企业二氧化硫、氮氧化物和二氧化碳的平均影子价格分别为59.8元/千克当量、388.13元/千克当量和164元/吨当量;2)研究时段...     

Temperature sensitivity of soil carbon decomposition and feedbacks to climate change

Significantly more carbon is stored in the world's soils--including peatlands, wetlands and permafrost--than is present in the atmosphere. Disagreement exists, however, regarding the effects of climate change on global soil carbon stocks. If carbon stored belowground is transferred to the atmosphere by a warming-induced acceleration of its decomposition, a positive feedback to climate change would occur. Conversely, if increases of plant-derived carbon inputs to soils exceed increases in decomposition, the feedback would be negative. Despite much research, a consensus has not yet emerged on the temperature sensitivity of soil carbon decomposition. Unravelling the feedback effect is particularly difficult, because the diverse soil organic compounds exhibit a wide range of kinetic properties, which determine the intrinsic temperature sensitivity of their decomposition. Moreover, several environmental constraints obscure the intrinsic temperature sensitivity of substrate decomposition, causing lower observed 'apparent' temperature sensitivity, and these constraints may, themselves, be sensitive to climate.