北京市生活垃圾中重金属元素的污染特性调查及对策

采用现场调研取样和理化分析检测的方法 ,对北京市城区垃圾中的重金属含量、主要污染元素和主要污染物进行测定 ,并在调查和分析的基础上 ,提出北京市城区垃圾中重金属污染的防治对策 ,为废弃物减量化、无害化与资源化提供了科学的依据和重要参考。     

Effect of spectral resolution on the measurement of monoaromatic hydrocarbons by DOAS

The excellent response characteristics and detection sensitivity with much lower operational cost and the capability to discriminate between the isomer of some monoaromatic hydrocarbons (MAHCs) make di erential optical absorption spectroscopy (DOAS) a powerful tool to trace concentration variation of MAHCs. But due to the similarity in chemical structure, those MAHCs have the similar overlapped characteristic absorption structures, which make the selection of instrumental parameter critical to the accurate detection of MAHCs. Firstly, the spectral resolution used in DOAS system determines the nonlinear absorption of O2 and the mass dependence of characteristic absorption structure; thereby it determines the effect of elimination error of O2 absorption in the atmospheric spectra for the detection of MAHCs. Secondly, spectral resolution determines the di erential absorption characteristics of twelve MAHCs representing major constituents in technical solvents used in the automobile industry and the interference of spectral overlapping. Thirdly, the spectral resolution determines the sensitivity, time resolution and linear range. So the spectral resolution range with the best ratio of signal to noise is used to determine the most suitable spectral resolution range, as well as the spectral resolution range that ensure the characteristic absorption structure of MAHCs and the minimization of O2 absorption interference. Finally, 0.15–0.16 nm (FWHM: full width at half maximum) is assumed to be closest to the optimum spectral resolution and it is confirmed by the results of practical measurement of MAHCs by DOAS.     

Municipal waste treatment efficiency in 29 OECD countries using three-stage Bootstrap-DEA model

Environment, Development and Sustainability - Rapid urbanization has led to a sharp increase in municipal waste generation, which has resulted in significant environmental problems. However, the...     

矮塔斜拉桥单侧断索和双侧对称断索影响效应分析

为研究断索现象对矮塔斜拉桥力学性能和安全性的影响，以浙江某实际工程为背景，使用Midas/Civil建立有限元模型，研究单侧单束断索和双侧对称断索两种工况分别对斜拉索索力、塔顶DX位移和主梁跨中弯矩的影响。研究发现：单侧断索对断索侧索力和跨中弯矩、主塔塔顶DX位移的影响较大；双侧对称断索对主塔两侧索力和跨中弯矩影响趋势相同，对边塔塔顶DX位移影响较大；最外侧斜拉索断裂对3个力学指标的影响均为最大，故实际运营中应重视对外侧斜拉索的保护。     

Applying rail transit construction waste to make building materials: using the theory of sustainable development

Environmental Science and Pollution Research - With the rapid development of the rail industry, a large amount of construction waste will be generated during the construction phase, posing a...