The effects of LMWOAs on biodegradation of multi-component PAHs in aqueous solution using dual-wavelength fluorimetry

Biodegradation of dissolved fluorene (Flu), phenanthrene (Ph) and pyrene (Py), three polycyclic aromatic hydrocarbons (PAHs), singly or as a mixture of the three, by two bacterial strains, MEBIC 5140 (Mycobacterium flavescens) and MEBIC 5141 (Mycobacterium scrofulaceum), as well as the effects of low molecular weight organic acids (LMWOAs), e.g. malic acid, citric acid and butyric acid on biodegradation of the three PAHs in mineral salts medium aqueous solution were investigated using a newly established dual-wavelength fluorimetric method. The results showed that biodegradation processes can be monitored simultaneously, quickly and simply by dual-wavelength fluorimetry. Both co-metabolism and inhibitory effects were found during the biodegradation of the three PAHs by MEBIC 5140 and MEBIC 5141. Positive effects of butyric acid and negative effects of citric acid on biodegradation of the three PAHs in a mixture were observed.     

自然灾害灾情的熵权综合评价模型

基于熵权理论提出了一种新的灾情综合评价模型.利用福建省2005-2006年主要台风灾害资料,选取受灾面积,成灾面积、受灾人口、死亡人数、倒塌房屋和直接经济损失6个指标对灾情进行评价.结果表明:应用熵权综合评价模型进行自然灾害灾情综合评价,避免了人为的主观任意性,评价结果与实际情况吻合得较好.因而,熵权综合评价模型是一种科学、实用的灾情评价方法.     

岩土震害影响因子权重研究——以砂土液化为例

以砂土液化影响因子的权重计算为例,探讨了一种兼顾主、客观因素的权重确定方法。首先分别使用层次分析法和粗糙集理论计算砂土液化影响因子的主、客观权重值。然后对所得到的主、客观权重值进行检验,得到各自的预测准确性,根据对其准确性进行比较得到主、客观权重值偏好系数,最终按照偏好系数对主、客观权重值进行计算得到综合权重值。并对所得到的综合权重进行验证,其预测准确率为91.7%,说明该方法具有比较高的准确性。通过研究发现,对主、客观权重通过偏好系数进行综合,可以较好的平衡两者的影响作用,能够提高权重分析的准确性;通过对砂土液化影响因子权重的分析发现地震作用对其影响要大于土体埋藏环境和土体自身性质,在所有影响因子中有效应力的影响最大,其权重达到了0.205。     

Macro,Meso, and Micro‐Efficiencies in Water Resources Management: A New Framework Using Water Balance1

Haie, Naim and Andrew A. Keller, 2012. Macro, Meso, and Micro‐Efficiencies in Water Resources Management: A New Framework Using Water Balance. Journal of the American Water Resources Association (JAWRA) 48(2): 235‐243. DOI: 10.1111/j.1752‐1688.2011.00611.x Abstract: One of the most important performance indicators for water resources systems (WRSs) management is efficiency. Here, water balance, based on mass conservation, is utilized to systemically develop three levels of composite efficiency indicators for a WRS, which are configurable based on two types of water totals: total inflow and total consumption (outflow that effectively is not available for reuse). The indices characterize hydrology of an area by including in their formulations the flow dynamics at three integrated levels. Furthermore, the usefulness of water is incorporated into the indicators by defining two weights: one for quality, and the other for beneficial attributes of water use. Usefulness Criterion is the product of quality and beneficial weights, emphasizing the equal significance of the two dimensions. Both of these weights depend on the system itself and the priorities of the supervising organization, which also are shaped by the objectives and values of the given society. These concepts lead to the definition of Macro, Meso, and Micro‐Efficiencies, which form a set of integrated indicators that explicitly promotes stakeholder involvement in evaluation and design of WRSs. Macro, Meso, and Micro‐Efficiencies should be maximized for both water totals, which is an integrated prerequisite for sustainability and is less promoted by competing stakeholders. To demonstrate this new framework, it is applied to published data for urban and agricultural cases and some results are explained.     

Effect of manganese on the concentration of amino acids in different regions of the rat brain

Abstract

The present study was designed to determine if chronic exposure of weanlings and adult rats to Mn produces significant alterations in amino acid concentrations in different regions of the rat brain. Weanling (30 day old) and adult (90 day old) male rats were exposed to 10 and 20 mg Mn/kg body weight per day, by gavage, for 30 days. Forty‐ eight hours after the last dose, animals were sacrificed by decapitation and brains were dissected into different regions to determine the concentration of amino acids by HPLC/EC. A dose dependent decrease in body weight gain was found in the adult, but not in the weanling rats. Significant increases occurred in concentrations of aspartate, glutamate, glutamine, taurine and y‐aminobutyric acid (GABA) in the cerebellum of the adult rats dosed with 20 mg/kg per day, Mn. A significant decrease in the concentration of glutamine was observed in caudate nucleus and hippocampus of weanling rats dosed with 10 mg/kg, Mn. These data suggest that chronic Mn exposure can produce a decrease in body weight gain in adult rats and alterations in amino acids in different regions of weanling and adult rat brains.     

混凝对二级出水中有机物分布特性的影响

以城市污水处理厂二级出水为研究对象,通过烧杯实验,确定了以三氯化铁(FeCl3)和聚合氯化铝(PAC)为混凝剂时两种混凝剂的最佳投加量,在此基础上采用XAD树脂分离技术和超滤膜法对水中溶解性有机物(DOM)进行分级表征,研究了混凝前后水中DOM的亲疏水特性、分子量分布规律以及比紫外吸收值(SUVA)和E4/E6(A465nm/A665nm)的变化.结果表明,当FeCl3和PAC投加量分别达到30 mg/L和60 mg/L时,可以使出水水质满足《城镇污水处理厂污染物排放标准》(GB18918-2002)中的一级A标准;FeCl3对含碳碳不饱和双键及芳香环的有机物的去除效果优于PAC;FeCl3对小分子有机物的去除效率更高,而PAC对分子量＞100 000的大分子有机物的去除效果优于FeC13;混凝处理对疏水性有机物的去除效果优于对亲水性有机物的去除效果,同时其对酸性物质的去除效率高于对非酸性物质的去除效率.     

中国城市能源系统可持续性评价体系实证研究

为明确城市能源系统状况,需对城市能源体系进行全面而细致的了解,本文在全面分析城市能源系统的基础上,建立了城市能源系统能源流动图,并对其进行简化建立适合建模的简化模型。进而对城市能源系统进行研究,归纳出城市能源系统的影响指标。然后利用层次分析法筛选出其中对评价对象辨别能力较强的关键因素,结合相应环境因素,建立了能够全面反映城市能源系统的综合评价指标体系。本文首次将模糊综合评价模型引入到能源评价体系权重确定中来,建立了多级城市能源系统综合评价指标体系模糊综合评价模型。通过对北京市2000-2007年相关能源数据进行实证分析,结果表明所建评价体系能够根据优化权重结果找出评价对象问题所在,加大评价对象的差异性,放大评价对象间的对比程度,使得评价结果更加明显;同时和等权重计算结果比较分析发现,优化后的评价结果更加合理,并更加接近城市能源的实际状况,能够为城市能源系统规划提供合理的量化依据。     

Influence of furfural concentration on growth and ethanol yield of Saccharomyces kluyveri

Furfural is an important inhibitor in ethanol fermentation process using lignocellulosic hydrolysates as raw materials.In order to find out the fuffural concentration range in which furfural inhibits the fermentation process,we used one strain Saccharomyces kluyveri selected from soil and cultured in several different furfural content media under low glucose concentration condition.Experiment results showed that microorganism growth was stimulated and dry cell weight decreased when furfural concentration in the medium was 0.25 mg/ml.Furfural had negative effect on cell growth when its concentration was above 1.00 mg/ml.At the same time,the strain growed better and had a higher glucose consumption rate in 5% original glucose concentration condition than in 3% original glucose concentration condition.The results showed that appropriate exaltation of original glucose concentration in stalk hydrolysates will increase the strain resistance to furfural.     

基于未确知测度理论的安全生产状况评价研究

为研究我国省市的安全生产级别,基于未确知测度理论,建立安全生产状况评价的等级模型。根据实际情况,选取5项评价指标,建立各评价指标的未确知测度函数。利用熵确定各项指标的权重,避免人为主观性对评价的影响,根据多指标综合测度评价向量和置信度识别准则进行评判。结合2009年9省市对应指标统计数据,采用未确知理论对安全生产状况进行评价,并结合实际进行分析。该理论为省、市安全生产提供了指导性的建议和依据。     

基于模糊贴近度和熵权的航空装备维修安全综合评价

航空装备维修安全是确保装备飞行安全的重要因素,为提高航空装备飞行的安全性,需要对航空装备维修安全进行准确评价。根据航空装备维修安全评价涉及的不确定性问题,采用模糊数学和熵理论,提出一种基于模糊贴近度和熵权的航空装备维修安全综合评价方法。在建立航空装备维修安全评价指标体系的基础上,采用熵确定各指标的权重值、加权平均算子确定综合评价集,利用非对称贴近度进行决策分析。通过对某型飞机调查数据的算例分析,确定航空装备维修安全的主要影响因素,得出该型飞机维修安全水平的评价值。