各类清洁能源小锅炉的适用性

随着城市经济建设和社会事业的发展,据《中华人民共和国大气污染防治法》的要求,城市中大量燃煤锅炉、窑炉及生活大灶等燃用高污染燃料设施,必需逐步淘汰。本文对目前常用的各类清洁能源的锅炉适用性和价格,做了一个较为详细的比较,为企业在锅炉改造和替换过程中,结合其自身的情况和特点,选择何种清洁能源的锅炉,具有一定参考价值和现实的指导意义。     

小秦岭地体新太古代构造-岩石单位及地史演化

小秦岭地体新太古代构造-岩石单位由老到新划分为观音堂岩组、焕池峪岩组、杨寨峪灰岩色片麻岩组、斜长角闪岩组和四范沟片麻状花岗岩组。杨寨峪灰色片麻岩组、观音堂岩组和焕池峪岩组呈侵入-构造接触关系,斜长角闪岩组和四范沟片麻状花岗岩组依次侵入于先成岩组中。     

中性点不接地电网中单相接地故障的分析及处理

阐述了中性点不接地电网中单相接地的特点,并分析了用绝缘监视装置和小电流接地选线装置查找故障的利弊,以及目前小电流接地选线技术可靠性差的原因.     

基于层次分析法（AHP）的环境绩效审计评价体系构建研究——以丽水市为例

文章构建了环境绩效审计综合评价指标体系,运用层次分析法确定指标体系的权重,对于提高环境绩效审计工作质量和效率具有重要意义。丽水市生态资金绩效审计的实证研究结果表明,指标体系评价结果能客观反映市县行政区实际,指明影响环境管理绩效的消极因素,能有效提高财政经费使用效益,充分发挥审计服务科学发展的作用。     

合同能源管理在电站锅炉引风机节能改造中的应用实践

本文介绍了天津国电津能热电有限公司与某节能服务公司合作,基于合同能源管理模式实施了公司内#2机组引风机的变频改造工作;通过该服务公司对项目设计、融资、设备采购、工程施工、设备安装调试、节能量确认等一整套的节能服务工作,风机改造取得了成功,不仅降低了能耗成本,还获得了良好的社会效益,为完成天津市＂十二五＂节能减排指标奠定了坚实的基础。     

大连小窑湾海域表层沉积物重金属潜在生态风险评价

基于2009年在大连小窑湾海域表层沉积物中的重金属监测数据,采用Hakanson生态风险指数法对湾内沉积物中的重金属的潜在生态风险进行了分析和评价,并对结果进行了地理空间表达,结果表明:调查研究海域的潜在生态风险较低,该海域的沉积物重金属潜在的生态风险因子为Cd和Hg。     

沙蚕暴露于石油烃、Cu2+和Cd2+毒性效应及乙酰胆碱酯酶活性的响应

采用浓度梯度污染暴露室内模拟方法,研究了沙蚕（Perinereis aibuhitensis Grube）暴露于不同浓度的石油烃和重金属Cu²⁺、Cd²⁺的毒性效应及乙酰胆碱酯酶活性的响应.结果表明,石油烃和Cd²⁺、Cu²⁺对沙蚕均具有较强的毒性效应.暴露4 d和10 d后,石油烃LC₅₀分别为440和110 μg·L^-1,Cu²⁺分别为1 150和570 μg·L^-1,Cd²⁺分别为5 090和2 500 μg·L^-1,相应的生态毒性大小为：石油烃＞Cu²⁺＞Cd²⁺.在Cd²⁺、Cu²⁺污染暴露条件下,沙蚕体内乙酰胆碱酯酶活性受到一定程度的抑制,但抑制率均低于50％.而在石油烃污染暴露条件下,沙蚕体内乙酰胆碱酯酶活性受到显著抑制,最高抑制率可达90％以上;而且,其乙酰胆碱酯酶活性的变化与石油烃的浓度显著相关.可见,乙酰胆碱酯酶活性的变化可以作为生物标志物,较灵敏地反映出石油烃对沙蚕的污染效应及其毒害作用.     

Cr（Ⅵ）对海洋浮游植物生长的影响

采用一次培养实验方法,研究了Cr（Ⅵ）污染物对海洋浮游植物生长的影响.结果表明高浓度Cr（Ⅵ）对8种浮游植物的生长普遍有抑制作用,而较低浓度Cr（Ⅵ）则易促进旋链角毛藻、青岛大扁藻及中肋骨条藻的生长.并且在Logistic生长模型的基础上结合Lorentz方程和GaussAmp方程,引入Cr（Ⅵ）污染物浓度项,建立Cr（Ⅵ）污染物条件下海洋浮游植物生长动力学模型,来描述Cr（Ⅵ）存在条件下海洋浮游植物的生长过程,其中Lorentz方程可描述Cr（Ⅵ）浓度的变化对浮游植物生长速率参数的影响,而GaussAm     

Effect of chromium on accumulation and antioxidants in Cucumis utillissimus L.: Response under enhanced bioavailability condition

This study compares the accumulation of Cr(VI) and biochemical changes (total chlorophyll, carotenoid, protein, malondialdehyde (MDA) and cysteine contents) and roles of antioxidant enzymes (superoxide dismutase (SOD), guaiacol peroxidase (GPX), ascorbate peroxidase (APX)) in tolerance to metal induced stress in Cucumis utillissimus L. grown in Cr contaminated soil (CS) with garden soil (GS). Furthermore, Cr bioavailability was enhanced by ethylene diamine tetra-acetic acid (EDTA) addition to the soil to forecast the plant’s accumulation pattern at elevated Cr environment. Accumulation of Cr in the leaves of the plant increased with increase in substrate metals concentration. It further increased with the addition of EDTA by 1437% and 487% in GS and CS, respectively at the highest treatment level. The lipid peroxidation increased proportionately with increase in Cr accumulation in the leaves. All the activity of antioxidant enzymes (SOD, GPX and APX) and the level of cysteine increased with dose dependant manner. SOD and cysteine were observed to be higher in the GS than in CS, but APX and GPX were found to be higher in CS than in GS. The increase in GPX and APX activities with the increase in Cr concentration could be assumed that these two enzymes have a major role in the defense mechanism towards stress induced by Cr in C. utillissimus.     

Sedimentary record of polycyclic aromatic hydrocarbons in Lake Erhai, Southwest China

The temporal distribution of polycyclic aromatic hydrocarbons (PAHs) was investigated in a sediment core from Lake Erhal in Southwest China using gas-chromatography/mass spectrometry (GC/MS) method.The total organic carbon (TOC) normalized total PAHs concentrations (sum of US Environmental Protection Agency proposed 16 priority PAHs) ranged from 31.9 to 269 μg/g dry weight (dw),and were characterized by a slowly increasing stage in the deeper sediments and a sharp increasing stage in the upper sediments.The PAHs in the sediments were dominated by low molecular weight (LMW) PAHs,suggesting that the primary source of PAHs was low- and moderate temperature combustion processes.However,both the significant increase in high molecular weight (HMW) PAHs in the upper sediments and the vertical profile of diagnostic ratios pointed out a change in the sources of PAHs from low-temperature combustion to high-temperature combustion.The ecotoxicological assessment based on consensus-based sediment quality guidelines implied that potential adverse biological impacts were possible for benzo(ghi)perylenelene and most LMW PAHs.In addition,the total BaP equivalent quotient of seven carcinogenic polycyclic aromatic hydrocarbons (BaA,CHr,BbF,BkF,BaP,DBA and INP) was 106.1 ng/g,according to the toxic equivalency factors.Although there was no great biological impact associated with the HMW PAlls,great attention should be paid to these PAH components based on their rapid increase in the upper sediments.