2.25Cr-1Mo与铁铝合金高温抗氧化性能的对比研究

对2．25Cr-10钢与铁铝合金的高温抗氧化性能进行了对比研究。铁铝合金具有许多性能上的优点，尤其在其高温抗氧化性能方面。明显优于不锈钢、铬钼钢等传统的高温结构材料，并且随着温度的升高及铝含量的增加，其优势更加显著。     

Heavy metal and chlorinated hydrocarbon contamination of selected aquatic sediments from the Berlin area

Sediments from the Berlin area were analysed for heavy metals and chlorinated hydrocarbons. the sedimentological and hydrogeological aspects of the Holocene sediments are discussed and an adapted sampling device for muds with a high water content is described. the contamination of surface sediments and dated cores is shown back in the 19th century; the hydrological influences on the degree of contamination and potential threats to groundwater and, via remobilisation, to surface waters are considered. It is concluded that the sediments of the Berlin area are highly contaminated.     

基于SD-SVD-Burg的玉米叶片铜铅污染甄别与程度诊断

为研究一种快速甄别作物受重金属污染的元素类别和所受污染程度的方法,于2017年设置不同梯度铜(Cu)、铅(Pb)胁迫下的玉米盆栽实验,对玉米的紫谷、绿峰和红边3个光谱特征区间的高光谱数据进行光谱一阶微分和奇异值分解处理,并结合Burg算法绘制功率谱密度曲线,同时利用2014年采集的光谱数据作为验证组检验该模型的稳定性。结果表明:健康玉米叶片与不同浓度Cu、Pb胁迫下玉米叶片光谱信号的功率谱密度曲线的波峰数及波峰坡度均不相同。功率谱曲线平均功率和玉米叶片中Cu、Pb含量的相关系数最高可达0.9958,证明该方法在对玉米进行污染元素种类辨别和污染程度诊断方面具有可行性,不同年份Cu与Pb胁迫下绿峰功率谱曲线平均功率与玉米叶片中Cu、Pb含量的相关系数分别为0.9213和0.9915,进一步验证该算法在玉米Cu、Pb污染诊断方面具有稳定性与普适性。     

信阳市主要野生水产动物重金属含量分析及质量安全评价

测定了信阳市主要野生水产动物Cd、Cr、Pb、As和Hg的含量,并根据单因子污染指数评价法对信阳市主要野生水产动物的品质进行质量安全评价。结果表明,8种信阳市主要野生水产动物的所有样品中均检出Pb和Cr,但均未检出Cd和Hg。在鲫鱼、鲤鱼、青虾和克氏原螯虾中检出As,检出率分别为60%、65.5%、55%和50%。单因子污染指数评价法表明,8种信阳市主要野生水产动物均受到不同程度的Pb污染,鲤鱼和鲫鱼受到了轻度的As污染。     

不同时期重截对大十果桑生长结果的影响

采果结束后对大十果桑结果母枝重截是其夏季修剪的主要内容。结果表明：采果结束时立即对结果母枝留3～4节重截提高次年产量和品质、减小树体、增强树势的综合效果最好。重截过迟,会严重削弱树势,造成次年大幅减产。叶果兼用时,为了克服因集中重截而造成断叶现象,可以在采果结束后30 d以内分期分批对结果母枝重截,对次年产量和品质的影响较小。     

茶叶中重金属及其检测方法研究概述

茶叶作为我国传统饮料和世界三大饮料之一,含有多种人体不可缺少的微量元素,具有保健和医疗功效,但近年来我国茶叶重金属超标问题屡见报端.本文概述了茶叶中重金属的来源、防治措施及其检测方法,为进一步研究提供文献线索.     

林芝河谷地区典型农田土壤主要性质及重金属状况初探

选择西藏林芝河谷地区代表性麦田及蔬菜大棚土壤,对其主要土壤肥力指标、重金属浓度及相应小麦及蔬菜样的重金属浓度进行了测定。结果发现:该区耕地土壤有机质、全氮、碱解氮处于中等及较缺乏水平,全磷、全钾、有效锌处于缺乏水平,速效磷、钾及有效铜处于较丰富水平;研究区土壤及作物铜、锌、镉浓度均未超出我国土壤环境质量标准,但农业生产活动造成了表层土壤铜、锌、镉的富集。研究区耕地应注重有机肥、化肥及微量元素的合理施用,同时注意农业生产活动造成的土壤酸化、重金属富集问题并加以监控,以促进该区农业的可持续发展。     

氧化节杆菌生物降解苯并芘

A pot experiment was conducted with multi-metal (Pb, Cd, Cu, and Zn) contaminated acidic soil to investigate changes in available metal burden resulting from the application of industrial wastes (fly ash and steel slag). The efficiency of amendments-induced metal stabilization was evaluated by diffusive gradients in thin films (DGT), sequential extraction, and plant uptake. The stability of remediation was assessed by an acidification test and by chemical equilibrium modeling. Addition of fly ash (20 g kg-1 ) and steel slag (3 g kg-1 ) resulted in similar increase in soil pH. Both amendments significantly decreased the concentrations of metals measured with DGT (C DGT) and the metal uptake by Oryza sativa L. Significant correlations were found between C DGT and the concentration of a combination of metal fractions (exchangeable, bound to carbonates, and bound to Fe/Mn oxides), unraveling the labile species that participate in the flux of metal resupply. The capability of metal resupply, as reflected by the R (ratio of C DGT to pore water metal concentration) values, significantly decreased in the amended soils. The C DGT correlated well with the plant uptake, suggesting that DGT is a good indicator for bioavailability. Acidification raised the extractable metal concentration in amended soil but the concentration did not return to the pre-amendment level. Equilibrium modeling indicated that the soil amendments induced the precipitation of several Fe, Al and Ca minerals, which may play a positive role in metal stabilization. Chemical stabilization with alkaline amendments could be an effective and stable soil remediation strategy for attenuating metal bioavailability and reducing plant metal uptake.     

设施蔬菜生产系统重金属积累特征及生态效应

研究土壤重金属的空间变异特征,可以揭示人为活动对土壤中重金属积累特征的影响,进而为土壤利用、污染风险评价提供重要的基础资料.选取南京市郊区一处典型的设施蔬菜生产系统为研究对象,测定了土壤、灌溉用水、肥料、蔬菜等介质中重金属砷(As)、镉(Cd)、铜(Cu)、汞(Hg)、铅(Pb)、锌(Zn)含量,研究了土壤中重金属的空间变异及积累特征,分析了积累产生的原因,讨论了系统中作物的重金属积累效应.结果表明:(1)与露天蔬菜地相比,设施蔬菜地土壤重金属Cu、Hg、Pb、Zn均产生明显的累积,且土壤中Cu、Hg、Pb平均含量超过温室蔬菜产地环境质量评价标准.(2)农用投入品的大量输入对土壤性质的空间变异产生了明显影响,而土壤Cu、Hg、Pb、Zn也呈现与之一致的空间变异特征,且这些元素与土壤性质存在显著相关性.(3)土壤性质的变化和重金属的积累对叶菜类作物重金属吸收影响较大,且前者更为重要.     

中药渣用于培养灵芝菌的研究及功能成分分析

该文利用中药渣培养灵芝菌，研究灵芝菌的最适发酵条件,子实体生长条件及其生物活性成分（灵芝多糖及灵芝三萜化合物）和重金属含量。结果表明：灵芝菌固体发酵最适温度为26～28℃，培养基含水量55～60%，pH5.0～6.0，氧气充足，无需光照；子实体的适宜生长条件为：温度25～30℃，空气湿度90%左右，pH4.0～6.0,氧气充足，需要光照。分析检测了灵芝酸多糖含量，重金属含量均在安全范围内。