能源资源开发与区域经济发展协调研究——以我国西北地区为例

本文探讨了能源资源富集、但经济发展相对落后的经济大区能源资源开发同地区经济协调发展的问题。侧重以我国西北地区为例,从实证的角度,阐述了能源开发对地区经济繁荣的意义和作用、富能地区经济系统的空间组织以及推动能源开发同可持续发展相互协调的区域政策要点。     

Adsorption of lead on multi-walled carbon nanotubes with different outer diameters and oxygen contents: Kinetics, isotherms and thermodynamics

The effects of different outer diameters and surface oxygen contents on the adsorption of heavy metals onto six types of multi-walled carbon nanotubes (MWCNTs) were investigated in an aqueous solution and lead was chosen as a model metal ion. The results indicated that the percentage removal and adsorption capacity of lead remarkably increased with decreasing outer diameter due to larger specific surface area (SSA). The SSA-normalized maximum adsorption capacity (qm /SSA) and SSA-normalized adsorption coefficient (Kd /SSA) were strongly positively correlated with surface oxygen content, implying that lead adsorption onto MWCNTs significantly increases with the rise of oxygen content and decreases with decreasing SSA. The calculated thermodynamic parameters indicated that adsorption of lead on MWCNTs was endothermic and spontaneous. When the oxygen content of MWCNTs increased from 2.0% to 5.9%, the standard free energy (△ G0 ) became more negative, which implied that the oxygenated functional groups increased the adsorption affinity of MWCNTs for lead. Through calculation of enthalpy (△ H0 ), G0 and free energy of adsorption (Ea ), lead adsorption onto MWCNTs was recognized as a chemisorption process. The chemical interaction between lead and the phenolic groups of MWCNTs could be one of the main adsorption mechanisms due to highly positive correlations between the phenolic groups and K d /SSA or q m /SSA.     

磺胺甲噁唑对猪粪堆肥过程中堆料性质与酶活性的影响

以猪粪、小麦秸秆为材料,研究了磺胺甲噁唑（SMZ）对高温堆肥过程中理化性质（温度、pH值、E₄/E₆）和酶活性（纤维素酶、磷酸酶、脲酶、多酚氧化酶）的影响.结果表明：SMZ对堆肥理化性质的影响与其浓度有关.高浓度（95 mg·kg^-1）SMZ会对微生物活性产生显著抑制作用,表现出堆肥温度难以达到无害化标准,堆料pH值较低（<9.0）.但高浓度（95 mg·kg^-1）SMZ能激活多酚氧化酶活性,且水提浸液E₄/E₆值较低.在堆肥过程中,SMZ对纤维素酶和脲酶活性呈现出“抑制-激活-抑制”的作用,50 mg·kg^-1的SMZ对纤维素酶产生不同程度的激活作用.相比之下,脲酶活性对SMZ的敏感性比纤维素酶更敏感,5 mg·kg^-1的SMZ即能显著抑制脲酶活性,中浓度（50 mg·kg^-1）的SMZ对碱性磷酸酶活性产生了显著的抑制作用.综上,SMZ通过影响酶活性而影响堆肥过程的物质转化.此外,SMZ浓度越大,种子发芽指数越低.当SMZ≥50 mg·kg^-1时,堆肥难以腐熟而对植物毒性较大.     

Supercritical water oxidation of polyvinyl alcohol and desizing wastewater：Influence of NaOH on the organic decomposition

Polyvinyl alcohol is a refractory compound widely used in industry. Here we report supercritical water oxidation of polyvinyl alcohol solution and desizing wastewater with and without sodium hydroxide addition. However, it is difficult to implement complete degradation of organics even though polyvinyl alcohol can readily crack under supercritical water treatment. Sodium hydroxide had a significant catalytic effect during the supercritical water oxidation of polyvinyl alcohol. It appears that the OH ion participated in the C-C bond cleavage of polyvinyl alcohol molecules, the CO2-capture reaction and the neutralization of intermediate organic acids, promoting the overall reactions moving in the forward direction. Acetaldehyde was a typical intermediate product during reaction. For supercritical water oxidation of desizing wastewater, a high destruction rate (98.25%) based on total organic carbon was achieved. In addition, cases where initial wastewater was alkaline were favorable for supercritical water oxidation treatment, but salt precipitation and blockage issues arising during the process need to be taken into account seriously.     

渭南市大气环境容量计算及控制对策研究

以修正A值法估算渭南市大气环境容量,为渭南市大气总量控制提供科学依据。以箱模型为基本模型,利用陕西省气象台整编的1961-2008年气象资料,推导出宏观总量控制修正A值法,除韩城市、潼关县、浦城县、白水县和富平县A值大于国标A值,其余渭南各市县A值小于国标A值。在新空气质量标准标准的要求下,渭南市SO2、NOx、PM10环境容量分别为19.55×104t/a、10.50×104t/a和18.97×104t/a。为了保证各分区的环境质量,中架点源排放量与低源排放量之和应小于各分区容量,韩城市应注意改善中、低源NO x排放,其它区县NO x剩余容量有限,在严格的新空气质量标准的要求下,应加强对各区县中架点源与低架源的NO x控制,重点控制水泥行业、炼焦业和机动车的NO x排放。从整个城市考虑,从整个渭南市污染源排放来看,SO2总体排放量超过环境容量12.917×104t/a,NO x总体排放量超过环境容量8.016×104t/a,为了减少其对周边城市的影响,应提高火电厂脱硫效率,重点加快电厂脱硝设施建设。     

环境风险评价综述及案例讨论

环境风险评价是目前我国环境保护工作发展的必然结果,是进行环境管理的重要依据。文章对环境风险评价的概念及分类、国内外研究进展、程序内容及技术方法进行了综述。文章根据《建设项目环境风险评价技术导则》要求,结合湖北某制药建设项目,从风险识别、风险预测及评价、风险事故防范措施等方面论述了项目环境风险评价的基本概念及一般程序。分析了目前环境风险评价存在的问题,并据此初步提出今后环境风险评价的发展方向和建议。     

基于支持向量机的湖泊生态系统健康评价研究

利用支持向量机在处理分类问题、小样本问题和泛化推广方面的优势,构建了基于支持向量机的湖泊生态系统健康评价模型.同时,对广州市最大的人工湖——白云湖的水质及生物群落情况进行了监测,最后运用该模型对白云湖生态系统健康状况进行了评价.评价结果表明,白云湖生态系统处于病态状态,不能达到其净化水质的设计作用.建议从提高进水水质、实施湖区截污和丰富生物量3方面改善白云湖生态系统健康水平.与传统熵权综合健康指数法和熵权模糊综合评价法相比,所建模型更加客观、科学地评价了湖泊生态系统健康状况,能够为湖泊生态系统健康管理提供一定依据,具有广阔的应用前景.     

Cd/Sb/Pb复合污染对竺麻生长及吸收富集特征的影响

通过盆栽试验,分析了不同浓度Cd/Sb/Pb复合作用下苎麻的生长响应及重金属吸收、富集和迁移特征变化。结果表明,低浓度Cd/Sb/Pb复合处理对苎麻生长及生物量没有产生明显影响,而高浓度条件下则产生明显抑制效应,株高变矮,茎粗变细及生物量明显减少。苎麻体内Cd、Pb和Sb吸收量与污染土壤具有直接相关性,随复合处理浓度增加明显增大。至最高污染浓度处理时,苎麻体内重金属吸收量以Cd>Sb>Pb,地上部含量分别达335.74 mg/kg、157.55 mg/kg和92.31 mg/kg。复合处理下苎麻地上部对Cd、Sb和Pb的富集系数分别在0.67~0.88、0.13~0.17和0.05~0.06之间,均表现为随复合处理浓度增加而减少变化。苎麻Cd、Sb和Pb的转运系数分别为0.81~0.92、0.38~0.46和0.53~0.73,其中Cd、Sb的转运系数随复合处理浓度增加而增大,Pb则随复合处理浓度增加而减少。苎麻对重金属Cd/Sb/Pb复合污染具有较好吸收累积及转运能力,相比生物量小的植物而言,是目前修复重金属Cd/Sb/Pb复合污染的理想植物。     

BAF去除氨氮关键影响因素研究

为探讨曝气生物滤池去除氨氮的关键因素,选取沈阳仙女河污水处理厂(40万t/d)现场进行实地研究。通过测定不同条件下(pH、进水COD浓度、溶解氧、温度、水力负荷)的氨氮去除率,并进行主成分分析结果显示,影响BAF工艺脱氮的关键因素是温度、溶解氧和水力负荷。当温度在14~30℃之间时,氨氮的去除率一直维持较高,当温度低于14℃时,氨氮的去除率较低;随着溶解氧浓度的增大,氨氮的去除率也随之升高,当溶解氧增加到5.6 mg/L时,氨氮的去除率达到80%~90%,接近饱和状态;在水力负荷为3.08~4.15 m3/(m.2h)之间时,氨氮的去除率上升,超过该值,则氨氮去除率下降。     

生产安全事故责任认定定量化方法的探讨

当前,我国生产安全事故的责任认定是在事故调查组分析调查事故原因后,对事故责任者承担的责任进行定性的责任认定,受一定的主观因素影响。为了避免主观因素的影响,本文提出了一种责任认定定量化方法,该方法首先从安全管理、安全技术和职业健康卫生三方面建立了完善的事故影响因素集;然后在分析事故原因后采用专家打分法(德尔菲法)确定各影响因素的影响度,并计算出与事故相关的责任者的累加影响度,即责任大小;最后根据事故造成的人员伤亡和经济损失情况对事故责任者作出处理。此方法对生产安全事故责任认定更加公正客观。