微生物燃料电池与好氧堆肥协同处理餐厨垃圾

实验主张将餐厨固体垃圾和餐厨废水分开处理,并研究微生物燃料电池(MFC)作为餐厨废水和堆肥渗滤液处理工艺的可行性,通过调节不同的有机负荷,分析其生物产电的潜力和处理效率。对于餐厨废水而言,3 000 mg/L是较为理想的处理浓度,输出电压最高,始终维持在0.5 V以上;高于此浓度时电压输出特性与底物浓度呈现反相关,输出电压略低于0.5 V。极化曲线,电化学阻抗分析等也都表明3 000 mg/L是较为理想的处理浓度。而且在各种浓度下经MFC处理后的餐厨废水去除率均在90%左右,出水COD均低于400 mg/L。至于堆肥渗滤液,虽然在产电性能、去除效果上较餐厨废水稍差一些,但整体上与餐厨废水呈现出相似的规律。以上结果表明,餐厨垃圾中的废水可以通过MFC有效的去除和实现能量的回收。     

昆明至瑞丽公路水毁灾害现状及基本类型

通过对国道３２０线昆明至瑞丽公路水毁灾害历年资料和实地调查分析研究,阐该公路水毁灾害的现状,并将全线的公路水划分为崩塌与滑坡、泥石流、水毁路基、路基沉陷与翻浆四种类型。     

桂西北肯福环境移民示范区土地利用对土壤肥力变化的影响

为了解肯福环境移民示范区农业土地利用对土壤肥力变化的影响,特对移民迁入前和移民迁入后第3年示范区的土壤养分变化进行了研究,分析了耕层土样的8个土壤养分指标。结果表明,示范区土壤肥力整体上呈下降趋势,但不同的养分元素含量变化又有差别,并且不同利用方式的土壤养分元素含量变化也存在差别,宜林类用地土壤肥力降低幅度最大。     

低密度聚乙烯悬浮接枝马来酸酐工艺废水的回用

在低密度聚乙烯悬浮接枝马来酸酐(MAH)的工艺过程中,分别采用工艺废水直接回用和补加MAH及相应添加剂后再回用的两种回用方式对工艺废水进行资源化利用。实验结果表明,将工艺废水补加MAH及相应添加剂后回用于接枝物的制备过程,所得产物的接枝率稳定在1.30%以上,凝胶含量(质量分数)低于0.018%,熔融指数为10.22~10.37g/10min,产物性能与采用原配方制得产物相近。将工艺废水进行资源化利用,每生产1t接枝产物可节省MAH0.33t,共计节约成本2 880元。     

Supervised neural computing solutions for fluorescence identification of benzimidazole fungicides. Data and decision fusion strategies

Benzimidazole fungicides (BFs) are a type of pesticide of high environmental interest characterized by a heavy fluorescence spectral overlap which complicates its detection in mixtures. In this paper, we present a computational study based on supervised neural networks for a multi-label classification problem. Specifically, backpropagation networks (BPNs) with data fusion and ensemble schemes are used for the simultaneous resolution of difficult multi-fungicide mixtures. We designed, optimized and compared simple BPNs, BPNs with data fusion and BPNs ensembles. The information environment used is made up of synchronous and conventional BF fluorescence spectra. The mixture spectra are not used in the training nor the validation stage. This study allows us to determine the convenience of fusioning the labels of carbendazim and benomyl for the identification of BFs in complex multi-fungicide mixtures.     

Are motorway wildlife passages worth building? Vertebrate use of road-crossing structures on a Spanish motorway

Numerous road and railway construction projects include costly mitigation measures to offset the barrier effect produced on local fauna, despite the scarcity of data on the effectiveness of such mitigation measures. In this study, we evaluate the utility of different types of crossing structures. Vertebrate use of 43 transverse crossing structures along the A-52 motorway (north-western Spain) was studied during spring 2001. Research centered on wildlife passages (9), wildlife-adapted box culverts (7), functional passages (6 overpasses, 7 underpasses) and culverts (14), with marble dust being used to record animal tracks. A total of 424 track-days were recorded, with most of the larger vertebrate groups present in the area being detected. All crossing structure types were used by animals, although the intensity of use varied significantly among them (Kruskal-Wallis test, p<0.05); culverts were used less frequently than other structures. Crossing structure type and width were identified as the most important factors in their selection for use. Wildlife passages and adapted culverts allowed crossing by certain species (wild boar, roe deer, Eurasian badger), which do not tend to cross elsewhere. These results highlight the importance of using both mixed-type structures and wildlife passages in reducing the barrier effect of roads.     

Quantitative Identification of Disturbance Thresholds in Support of Aquatic Resource Management

The identification of disturbance thresholds is important for many aspects of aquatic resource management, including the establishment of regulatory criteria and the identification of stream reference conditions. A number of quantitative or model-based approaches can be used to identify disturbance thresholds, including nonparametric deviance reduction (NDR), piecewise regression (PR), Bayesian changepoint (BCP), quantile piecewise constant (QPC), and quantile piecewise linear (QPL) approaches. These methods differ in their assumptions regarding the nature of the disturbance-response variable relationship, which can make selecting among the approaches difficult for those unfamiliar with the methods. We first provide an overview of each of the aforementioned approaches for identifying disturbance thresholds, including the types of data for which the approaches are intended. We then compare threshold estimates from each of these approaches to evaluate their robustness using both simulated and empirical datasets. We found that most of the approaches were accurate in estimating thresholds for datasets with drastic changes in responses variable at the disturbance threshold. Conversely, only the PR and QPL approaches performed well for datasets with conditional mean or upper boundary changes in response variables at the disturbance threshold. The most robust threshold identification approach appeared to be the QPL approach; this method provided relatively accurate threshold estimates for most of the evaluated datasets. Because accuracy of disturbance threshold estimates can be affected by a number of factors, we recommend that several steps be followed when attempting to identify disturbance thresholds. These steps include plotting and visually inspecting the disturbance-response data, hypothesizing what mechanisms likely generate the observed pattern in the disturbance-response data, and plotting the estimated threshold in relation to the disturbance-response data to ensure the appropriateness of the threshold estimate.     

开拓进取, 服务大局, 迎接挑战——南京市环境监测新世纪寻求新突破

阐述了环境监测工作中存在的问题及环境监测部门面临新形势应如何采取对策迎接挑战。指出环境监测工作中存在的主要问题是“说不清”、“跟不上”和“不规范”，提出环境监测部门应树立全局意识，围绕大局，紧贴中心，在综合决策服务上寻求新的突破；树立质量意识，在为管理提供技术支持上寻求新的突破；树立竞争意识，培育中介机构，在市场竞争中寻求新的突破；树立忧患意识，在转变作风、提高效能上寻求新的突破。     

利用啤酒废水培养极大螺旋藻

利用啤酒废水培养极大螺旋藻（Spirulina maxima）。研究了初始COD、DO、氮磷元素等培养条件对藻生物量（每mL培养液中极大螺旋藻的质量,以干重计）及废水水质的影响。实验结果表明：将废水稀释至COD=700 mg/L,控制DO=2.5 mg/L,并添加氮磷元素使废水的碳氮磷质量比为225∶15∶1,培养3 d,极大螺旋藻的藻生物量可达175.55 mg/L,即每吨啤酒废水可生产极大螺旋藻175.55 g;废水中COD,TN,NH₃-N,NO₃^-,TP的去除率分别达到85.43%,94.54%,74.66%,94.53%,61.54%。利用啤酒废水培养螺旋藻在收获极大螺旋藻生物质的同时,还能对废水起到一定程度的净化作用。     

PCB118对GT1-7细胞GnRH分泌及Kisspeptin/GPR54信号通路蛋白表达的影响

为研究多氯联苯118(polychlorinated biphenyl 118,PCB118)对GT1-7细胞的毒性作用,探讨其对促性腺激素释放激素(gonadotropin-releasing hormone,GnRH)分泌的影响及相关机制,在PCB118作用GT1-7细胞后,分析了细胞存活率、GnRH分泌水平以及Kisspeptin/GPR54信号通路中关键蛋白的表达水平。结果表明,PCB118(0.05～50 000 nmol·L-1)分别作用GT1-7细胞6、12、24和48 h后,细胞存活率随PCB118浓度的增加和作用时间的延长而显著降低。但只有在高浓度(50 000nmol·L-1)条件下,PCB118才能显著促进GT1-7细胞释放乳酸脱氢酶(lactate dehydrogenase,LDH)。PCB118作用GT1-7细胞6 h后,5、500和50 000 nmol·L-1组能显著抑制GnRH的分泌,并降低Kisspeptin/GPR54信号通路中GnRH、G蛋白偶联受体54(G-protein-coupled receptor 54,GPR54)、磷脂酶C(phospholipase C,PLC)和蛋白激酶C(protein kinase C,PKC)等关键蛋白的表达水平;作用24 h,500和50 000 nmol·L-1PCB118能显著抑制GnRH的分泌,并降低GnRH、GPR54、PLC和PKC等关键蛋白的表达水平。研究表明:PCB118对GT1-7细胞具有细胞增殖毒性作用,呈现一定的剂量和时间效应; PCB118能在一定程度上抑制GT1-7细胞GnRH的合成与分泌,并下调Kisspeptin/GPR54信号通路中GnRH、GPR54、PLC和PKC等关键蛋白的表达水平,推测Kisspeptin/GPR54信号通路可能参与介导了PCB118对GT1-7细胞GnRH分泌的抑制作用。