城市小区雨水利用的模拟分析

选取天津市某小区,采用美国环保署开发的SWMM模型,模拟得出小区在开发建设前后的区域出口流量过程线和总径流量,分析评价了蓄水池和下凹绿地对小区雨水径流情况的影响。计算满足建设用地外排雨水设计流量不大于开发建设前水平这一条件时,蓄水池的设计体积和下凹绿地的面积以及下凹深度。模拟结果表明,蓄水池和下凹绿地可同时消减洪峰,推...     

三峡库区湖北段工业源污染负荷与预测

针对三峡库区工业源污染排放量大,对库区水生态环境安全危害大的特点,以库区湖北段工业源为研究对象,采用实际监测和企业申报监测数据方式,辅以排污系数计算方法,统计分析了1995-2007年工业废水量和主要污染物COD的排放量,并采用灰色-马尔柯夫链模型预测2008-2020年的污染负荷.结果表明,自2005年以后,工业废水的排放量呈现逐渐下降的趋势,在2007年达到1 857.13万t,2008年以后逐渐增加.COD的排放量总体呈逐渐下降的趋势,只是在2001年出现上升,到2007年底COD的排放量为611.21 t.随着工业源污染物全防全控的加强,预计工业污染负荷会逐步减少.     

典型区域土壤中PCB-11的污染特征

利用高分辨气相色谱/高分辨质谱法研究了土壤中PCB-11（3,3＇-二氯联苯,CAS 2050-67-1）的污染特征和分布规律,探讨了土壤中PCB-11的污染来源.结果表明,我国一般城市地区（天津、鞍山）和电子垃圾拆解地周边土壤中PCB-11的检出率为100%,PCB-11可能广泛存在于土壤介质中.天津、鞍山、电子垃圾...     

锅炉屏式过热器近集箱处爆管原因分析及改进措施

某电厂锅炉屏式过热器管在近集箱处发生爆管,本文通过宏观形貌检查、化学成分分析、机械性能测试及金相组织分析等方法对其爆管原因进行了系统分析。根据分析结果推断:集箱或管子内异物堵塞,导致管子材质劣化,但仅更换炉内管段,未更换炉外材质劣化管段,最终在长期运行中发生爆管。最后针对具体失效原因,提出了普查屏过管、失效分析、清洁工程及加强监督等改进措施。     

火焰原子吸收法测定水中铁的不确定度评定

测量不确定度是表征合理地赋予被测量值的分散性,与测量结果相联系的参数,通过火焰原子吸收分光光度法对水中铁的不确定度进行评定,确定铁测量不确定度的来源主要为工作曲线拟合、消解过程、重复测定和分析仪器,最主要来源是工作曲线,其他测量因素引起的分量较小,可以不予考虑。通过合理选择不确定度分量,优化评定过程,减少评定环节,达到对不确定度合理评定的目的。     

Impact of waste of COVID-19 protective equipment on the environment,animals and human health: a review

Environmental Chemistry Letters - During the Corona Virus Disease 2019 (COVID-19) pandemic, protective equipment, such as masks, gloves and shields, has become mandatory to prevent person-to-person...     

Quantifying ecosystem service mismatches for land use planning: spatial-temporal characteristics and novel approach—a case study in Jiangsu Province,China

Environmental Science and Pollution Research - Land use and land cover changes associated with urbanization have had a significant influence on ecosystem services (ESs), but previous studies have...     

OMEGA算法在导弹振动工程中的应用

目的研究位移、速度和加速度谱之间的转换关系,给出三者功率谱密度之间的转换公式,进而用于导弹运输振动环境的设计。同时,研究加速度信号转换为振动位移的方法,并应用于导弹舱内单机设备安全间隙的设计。方法利用OMEGA算法,首先将加速度传感器测得的加速度时域信号转换成加速度频域信号,随后将加速度谱转换成位移谱,并计算位移谱中每个谱线对应的幅值、相位和圆频率,最后将各位移分量简单叠加得到振动位移的时间历程。结果采用该方法计算了高速公路上导弹的运输振动位移功率谱,并得到垂向、横向和纵向的峰-峰位移分别为3.32,0.46,2.14 mm。同时,计算了飞行环境下导弹舱内单机设备的振动位移,与所测得位移在幅值上相当,时域曲线形态一致。结论该方法能够很好地应用于导弹振动工程设计。     

Characterization of phosphorus species and modeling for its organic forms in eutrophic shallow lake sediments,North China

Variations of phosphorus （P） and its species in surface sediment of Baiyangdian Lake, a eutrophic shallow lake located in North China, were investigated through combination of field survey and numerical calculation based on cluster analysis. P fractionation was performed by a sequential extraction scheme, categorized as loosely bound P （NH4Cl-P）, reductant soluble P （BD-P）, metallic oxide bound P （NaOH-P）, calcium bound P （HCl-P） and organic P （Org-P）. P concentrations exhibited regional similarities and a total of four sub-areas were identified in which the same rank was HCl-P 〉 Org-P 〉 BD-P ,=NaOH-P 〉NH4Cl-E NH4Cl-P, BD-P and Org-P were found to contribute to P enrichment in overlying water column. Specifically, labile Org-P acted as a potential pool with a greater contribution in aerobic layer compared to anaerobic layer. A hysteresis （lag = 4 months） existed when labile Org-P concentration was negatively correlated with aerobic layer thickness. In view of magnitude of identified P contributors in sub-areas, higher potential of P release was present in Fuhe River and Tang River estuary areas. On the basis of calibration and verification, the mathematical model with parameter settings applied in this study was improved to serve as a tool for limnology management and eutrophic control.