采用不同滑面材料的滑坡模型试验研究

为研究滑坡模型试验中不同材料模拟滑带土对模型稳定性的影响,以堆载为试验方法,以位移计为主要的测试手段,进行了采用草木灰、单层塑料薄膜、双层塑料薄膜作为滑面材料的两种工况5组模型试验。通过增加模型上的堆载,增大滑体的下滑力,使滑体最终发生滑动。根据试验的初始稳定状态、最终稳定状态及监测到的模型位移曲线,确定滑坡的极限平衡状态;同时根据最终加载量,反算出滑带土模拟材料的相似抗剪强度;得出不同滑面材料的稳定性及相似抗剪强度,为滑坡支挡模型试验提供试验基础。     

3,4-Dimethylpyrazol phosphate effect on nitrous oxide, nitric oxide, ammonia, and carbon dioxide emissions from grasslands

Intensively managed grasslands are potentially a large source of NH3, N2O, and NO emissions because of the large input of nitrogen (N) in fertilizers. Addition of nitrification inhibitors (NI) to fertilizers maintains soil N in ammonium form. Consequently, N2O and NO losses are less likely to occur and the potential for N utilization is increased, and NH3 volatilization may be increased. In the present study, we evaluated the effectiveness of the nitrification inhibitor 3,4-dimethylpyrazol phosphate (DMPP) on NH3, N2O, NO, and CO2 emissions following the application of 97 kg N ha(-1) as ammonium sulfate nitrate (ASN) and 97 kg NH4+ -N ha(-1) as cattle slurry to a mixed clover-ryegrass sward in the Basque Country (northern Spain). After slurry application, 16.0 and 0.7% of the NH4+ -N applied was lost in the form of N2O and NO, respectively. The application of DMPP induced a decrease of 29 and 25% in N2O and NO emissions, respectively. After ASN application 4.6 and 2.8% of the N applied was lost as N2O and NO, respectively. The application of DMPP with ASN (as ENTEC 26; COMPO, Münster, Germany) unexpectedly did not significantly reduce N2O emissions, but induced a decrease of 44% in NO emissions. The amount of NH4+ -N lost in the form of NH3 following slurry and slurry + DMPP applications was 7.8 and 11.0%, respectively, the increase induced by DMPP not being statistically significant. Levels of CO2 emissions were unaffected in all cases by the use of DMPP. We conclude that DMPP is an efficient nitrification inhibitor to be used to reduce N2O and NO emissions from grasslands.     

滑坡灾害微型桩连梁的作用

通过有限差分法(FLAC3D)模拟,探求了微型桩群桩加固滑坡过程中连梁的作用。模拟结果表明,加连梁时其安全系数比不加连梁要提高6%;在承担的滑坡推力上而言,不加连梁情况下,其承担的推力最大值比加连梁时要至少大90%;比较每排桩承担滑坡推力的分配比例,其结果差异很大,无连梁时不利于均匀布桩,而有连梁时更能节省桩的成本;有无连梁对其弯矩的影响不是很明显。根据模拟结果,采用相似比可推及一般的微型桩,其结果可为设计微型桩时考虑连梁作用提供参考。     

轻质陶粒曝气生物滤池处理城市污水厂二级出水的试验研究

模拟秦皇岛港务局中水厂处理工艺，试验确定出低浓度进水下的BAF最优水力负荷、容积负荷和气水比等可控参数，指导水厂运行。     

Sources and risk assessment of metal contamination in soils at the international airport of Shanghai,China

Concentrations of Cd, Pb, Zn, Cr, Cu, and Ni in soils at the Pudong International Airport (PIA) of Shanghai, China, were determined to assess the sources and potential ecological risks. Compared to the soil background values of Shanghai, 31 soil samples out of 33 were highly contaminated with Cd, and 76% were moderately contaminated by Cr, Ni, Pb, and Zn. Principal component analysis and clustering analysis indicated that Pb and Cd mainly originated from anthropogenic sources, while Zn, Cr, Ni, and Cu were mainly from natural sources. Relatively high concentrations of Cd and Pb were observed at sampling points near the landing or take-off sites or a close-by highway. Both air and highway traffic affected the quality of the soils at PIA.     

纳米材料与环境污染物的复合毒性

纳米材料因其独特的物理化学性质,不仅其自身具有毒性,还会与共存污染物相互作用,影响彼此的迁移转化和毒性效应。文中总结了纳米复合污染毒性的研究方法,并介绍了几种纳米材料(碳纳米材料、金属氧化物、量子点和零价金属)与重金属或有机物复合时造成的生物毒性,包括不同层次毒性指标响应(生物整体、生物积累、大分子水平)和毒性机制的探讨,展望了纳米复合污染毒性领域今后的发展方向和亟待研究的重要问题。     

电镀重金属污泥的水泥固化／稳定化处理

电镀重金属污泥经425号水泥固化后;其中混凝土:污泥为40:1或50:1样本的强度(28d)可达275号水泥的标准,且对Zn、Cu、Ni、Cr离子的固化效果好;在体系中添加粉煤灰及水玻璃,其早期的固化效果或产物强度低;混凝土:铁氧体污泥(湿法合成,FeSO_4·7H_2O:污泥=4:1)为30:1体系中,固化效果与稳定性均好,且产物强度可达325号水泥标准。     

TSP(IP)采样方法研究及比较

对现行的颗粒物采样的几种方法进行了对比研究。用几种方法同地点进行同步采样，样品微观观测结果表明；几种采样方法所采集的样品中，最大颗粒物的几何尺寸有明显的不同；样品分析及统计结果表明：几种采样方法所得监测结果之间存在着非常好的相关性。通过计算可相互通用，具有可比性；同时给出几种方法相互间的计算公式，可信度区间及可信度。     

基于GIS的中秦岭地区滑坡灾害易发性研究

本文以中秦岭地区为滑坡易发性评价对象,针对研究区的情况,选取了坡度、起伏度、地貌类型、岩性、土壤侵蚀强度、活动断裂距、地震动参数、地下水类型、多年平均降雨量9个评价因子,建立了研究区滑坡易发性评价的数据库。运用单因子概率比率模型对各因子和滑坡的相关性进行了评价,揭示了该区滑坡灾害类型特点及空间分布规律,明确了中秦岭地区滑坡地质灾害的极高易发、高易发三大聚集地区的位置。     

珠江隧道多环芳烃的含量与分布特征

为研究机动车尾气排放多环芳烃的排放特征,以及其从源到汇的过程变化,该研究选取珠江隧道为研究区域,采集了2006年4月、7月和12月珠江隧道中气相和颗粒相样品,以及7月、12月份隧道附近的大气样品,并对样品中多环芳烃(PAHs)进行检测.结果表明,隧道中馪AHs范围为896.1 ng·m-3～4066.2 ng·m-3,气相中馪AHs远远高于颗粒相馪AHs.环境大气样品中馪AHs为207.9 ng·m-3～353.0 ng·m-3,远远低于隧道里馪AHs,其PAHs各组分的分布特征与隧道中样品相似,说明汽车尾气是广州市大气中PAHs的重要来源;最后通过隧道中与隧道口的馪AHs来计算汽车的排放因子,得出PAHs排放因子平均值为:2164.7 靏穔m-1妨,并且估算出2006年广州市全年汽车尾气排放出PAHs 82 t.