城市固体废物焚烧炉飞灰中重金属酸溶出研究

对城市固体废物(MSW)焚烧炉飞灰中Cu,Pb和Zn 3种重金属的酸溶出过程进行了研究,结果显示在选用的3种不同浓度的酸中,只有浓度为0.5 mol/L的酸对3种重金属的溶出较理想.研究表明采用0.5 mol/L的酸对飞灰溶解搅拌约3 h后便可溶出大约50%~80%的Zn、40%~55%的Pb和50%左右的Cu,同时一些易溶金属如Mg,Ca和Al也大量溶出,但Fe和Si在飞灰中相对稳定,溶出量相对较少.飞灰经过酸处理后基本上可以满足填埋要求.     

水洗预处理对垃圾掺烧污泥焚烧飞灰中重金属高温挥发特性的影响

对某垃圾掺烧污泥焚烧厂焚烧飞灰进行采样,在研究重金属形态分布的基础上,重点研究飞灰水洗前后重金属(Cu、Zn、Pb、Cd)高温处置过程中的挥发特性。研究结果表明:飞灰中重金属酸可交换态中Cd的比例最大,其次为Zn,而重金属Cr,Ni和Mn主要以残渣态存在。高温处置过程中,飞灰中Pb表现出最易挥发的特性,其挥发率超过80%,而Cu挥发性较小,其挥发率30%,4种重金属的挥发性从大至小依次为:Pb,Cd,Zn,Cu。水洗飞灰中Zn的挥发率最高,超过20%,而Cu挥发性最小,水洗飞灰中重金属的挥发性从大至小依次为:Zn,Pb,Cd,Cu。在受热时间为120 min、加热温度为900℃条件下,飞灰水洗后Zn,Pb,Cd和Cu的挥发率分别降低了6.87%,70.24%,34.73%和9.52%,其中水洗脱Cl是重金属挥发率降低的主要原因。     

生活垃圾焚烧飞灰重金属固化特性

针对生活垃圾焚烧飞灰中重金属元素(Cr、Cd、Cu、Pb、Zn)含量过高导致的飞灰资源化利用难及其环境污染风险问题,结合连续萃取实验(BCR)及超声波辅助水洗,探究重金属赋存形态对飞灰重金属元素固化特性的影响。研究结果表明：超声波辅助水洗对飞灰中重金属元素固化效果较好,其中Cd固化效果最佳(98.87%),Cu固化效果最差(80.14%)。水洗使飞灰中的可溶性氯盐(NaCl、KCl、CaClOH)发生重组,生成新的化合物(CuCl、硫酸钙水合物、CaSO₄)。水洗后飞灰中重金属元素的赋存形态发生改变,Cr的可移动态占比可达93%,Cd赋存形态总体变化不大,Cu的赋存状态由残渣态向可还原态转变,Pb酸溶态占比下降,Zn残渣态和可还原态占比明显上升。     

污泥农用对碱性土壤重金属元素形态分布的影响

采用一种新的连续浸提方法,研究污泥长期(8 a)施用对碱性土壤中Zn、Cu、Ni、Cd和Pb元素的总量及元素形态分布的影响。结果表明:污泥农用显著增加了土壤中Zn、Cu、Cd和Pb元素的总量,而对Ni元素的总量无显著影响;土壤中Zn、Ni、Cd和Pb元素的主要存在形态为残渣态(61%~84%),其次为乙二胺四乙酸(EDTA)提取态,而Cu元素主要为EDTA提取态(42%);污泥农用对土壤中Ni和Pb元素的形态分布无显著影响,但提高了Zn、Cu和Cd元素的EDTA提取态、Zn和Cu元素的有机质结合态以及Cd元素的残渣态比例,而且减小了Zn元素的残渣态、Zn和Cu元素的晶体铁铝氧化物结合态、Cu元素的醋酸-醋酸钠提取态以及Cd元素的可交换态比例;土壤重金属总量、p H和有机质含量是影响重金属元素形态分布的主要因素。     

利用白菜修复污灌区重金属污染土壤的螯合诱导植物修复技术

以沈阳张士灌区重金属污染土壤为修复对象,采用盆栽试验,研究了乙二胺四乙酸（EDTA）对白菜富集重金属及其生长状况的影响．结果表明,EDTA能够提高白菜对土壤中Cu、CA、Pb和Zn的植物提取效率．受EDTA与不同重金属络合能力的影响,EDTA辅助提取Cd和Zn的有效施加量高于提取Cu和Pb的有效施加量,其对Cu、Pb和cd、zn的有效施加质量摩尔浓度分别为3mmol·kg-1和5mmol·kg-1植物提取效率随着EDTA施加量的增加而升高．高质量摩尔浓度EDTA的施用降低了白菜地上部的生物量,因此,在实践应用中应在植物已具有较高生物量的情况下进行EDTA的施加,从而避免因植物生长受抑制而导致的植物提取效率降低．     

不同螯合剂对土壤中重金属释放特征的影响

采用HCL、EDTA及DTPA作为化学螯合剂,研究土壤中螯合剂-重金属稳定平衡体系重金属释放特征,初步探讨该稳定平衡体系中重金属释放的时间效应以及螯合剂对重金属释放的影响.结果表明:a.加入浸提剂后有效态Cu的释放速度明显增加,加入浸提剂后2 h以上,达到较好的活化效果;b. 加入浸提剂的土壤样品中有效态Cd和Zn的释放量有所增加,但活化作用不明显;c.加入浸提剂的土壤样品中有效态Pb的释放量明显增加,表明在较短的时间内浸提剂对Pb具有明显的活化作用;d.三种浸提剂中,HCL对四种重金属Cu、Cd、Zn、Pb的浸提效果好于EDTA和DTPA.     

污染土壤中重金属的可萃取性与生物可利用性

采用5种常用的单一萃取剂进行污染土壤中重金属元素Cu、Pb、Zn和Cd可萃取性研究。结果发现：中性盐CaCl2和NaNO3的萃取效率远低于其它三种具有络合（HOAc、NH4OAc）或螯合（EDTA）性质的单一萃取剂；污染土壤中生长的农作物（玉米和土豆）体内重金属含量也高于中性盐CaCl2和NaNO3从土壤中萃取出来的量。这说明植物不仅可以吸收和利用土壤中以可交换形式存在的这一部分重金属，而且它们也可利用以其它形式存在的重金属。     

重金属污染土壤化学萃取修复技术影响因素分析

研究了重金属污染土壤化学萃取修复技术中一些关键因素对重金属萃取效率的影响．研究发现,腐殖酸对Cu和Zn在萃取剂中的溶解有促进作用,而对Pb和Cd有阻碍作用;粘土比砂土中的重金属更难于被萃取出来;酸性过强的土壤容易使EDTA发生质子化,从而降低其萃取能力;EDTA对Pb和Cd,OA对Cu和Zn分别表现出了强的萃取能力;生物表面活性剂可以作为添加荆来提高重金属的萃出效率。     

大气悬浮颗粒物中重金属含量和形态分析

对某大学校园内教学区、生活区和校外交通干道3个采样点秋冬季的大气颗粒物(TSP和PM10)浓度和颗粒物中的重金属元素Cu、Zn、Pb和Cr的浓度和形态分布进行了研究分析.结果表明:不同区域的TSP和PM10浓度差别较大,其中教学区最高,校外交通干道次之,生活区最低.TSP和PM10中Cu和Cr的含量较低,Zn和Pb的含量较高.TSP中重金属的总含量大于PM10,但是PM10中重金属所占的百分比大于TSP.从形态分布来看,TSP中Zn有40.76%存在于残渣态(S5)中,PM10中Zn有53.43%存在于可交换态(S1).而TSP和PM10中Cu在S1～S4中分布较多,Pb主要存在于残渣态(S5)中,Cr的主要存在形态是氧化物结合态(S3)和残渣态(S5).对TSP和PM10中重金属的生物有效性评价可知,Cu的可生物利用态含量最高,Zn、Pb和Cr的可生物利用态含量较低.     

危险废物焚烧飞灰中重金属污染特性

以危险废物(70%工业废物 30%医疗废物)焚烧飞灰为研究对象,探讨了飞灰中重金属污染特性及其主要化学形态、浓度分布规律.初步得出以下结论:危险废物焚烧飞灰中主要污染重金属为Cd,Pb,Zn,其数量高于生活垃圾焚烧飞灰数倍,属于危险废物;飞灰中主要重金属以可溶及交换态、残留态、Fe-Mn氧化物结合态为主要化学形态,其中As,Cr, Cu比较稳定,而Cd,Pb,Zn易溶出进入环境;飞灰中Cd,Cu大体上呈易富集在小颗粒的趋势,Pb,Zn集中分布在50～125,125～250μm的两个粒级.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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