A Superiority-Inferiority-Based Inexact Fuzzy Stochastic Programming Approach for Solid Waste Management Under Uncertainty

A superiority–inferiority-based inexact fuzzy stochastic programming (SI-IFSP) model was developed for planning municipal solid waste management systems under uncertainty. The SI-IFSP approach represents a new attempt to tackle multiple uncertainties in objective function coefficients which are beyond the capabilities of existing inexact programming methods. Through introducing the concept of fuzzy random boundary interval, SI-IFSP is capable of reflecting multiple uncertainties (i.e., interval values, fuzzy sets, probability distributions, and their combinations) in both the objective function and constraints, leading to enhanced system robustness. The developed SI-IFSP method was applied to a case study of long-term municipal solid waste management. Useful solutions were generated. A number of decision alternatives could be generated based on projected applicable conditions, reflecting the compromise between system optimality and reliability as well as the tradeoffs between economic and environmental objectives. Moreover, the consequences of system violations could be quantified through introducing a set of economic penalties, reflecting the relationships between system costs and constraint violation risks. The results suggest that the proposed SI-IFSP method can explicitly address complexities in municipal solid waste management systems and is applicable to practical waste management problems.     

Phytoremediation of phenol using Polygonum orientale,including optimized conditions

Removing phenol from wastewater has become a major challenge of international concern. Phytoremediation is a novel and eco-friendly method and is attracting an increasing amount of attention for treating phenol in wastewater. We studied the ability of Polygonum orientale, which is frequently present around water bodies and in wetlands in China, to phytoremediate phenol. We determined the inhibition concentration for phenol on P. orientale using emergency toxicology experiments and morphological observations. Isothermal and kinetic models were created to assess the adsorption process involved in phenol removal. Comparison tests in sterile conditions demonstrated that metabolic removal was the main way in which the phenol concentrations were decreased, and removal by adsorption played a smaller role. An orthogonal test was performed to determine the optimum conditions under which P. orientale will remove phenol, and these were found to be an initial phenol concentration of 5 mg L^?1, 100 % natural light, and a 13-day treatment time. These results provide a theoretical basis for increasing our understanding of the mechanisms involved in the removal of phenol by P. orientale and will help in developing its application in the greening of urban areas to provide both phytoremediation and esthetic landscaping.     

Polycyclic aromatic hydrocarbons in urban soils of Hangzhou: status,distribution, sources,and potential risk

Concentration, composition profile, spatial distribution, sources, and health risk of 16 polycyclic aromatic hydrocarbons (PAHs) were analyzed in 69 surface soil samples collected from Hangzhou urban districts. ∑PAHs ranged from 180.77 to 1,981.45 μg kg^?1 with a mean of 611.28 μg kg^?1. Among different functional areas, a higher level of PAHs was found in the roadsides, followed by commercial districts, residential areas, parks, and greenbelts. The composition of PAHs was characterized by high molecular weight PAHs (4?~?6 rings). Principal component analysis (PCA) and PAH isomeric ratios indicated that PAHs mainly originated from combustion, especially vehicle exhaust. The incremental lifetime cancer risks (ILCRs) associated with exposures to PAHs in soil were calculated separately for children and adults under normal and extreme conditions. The results showed that ILCRs for urban soil of Hangzhou were acceptable. However, attentions should be attracted on the sites of high PAH concentrations because the ILCRs were closed to 10^?4 under extreme conditions, especially for children.     

Multi-model ensemble simulation and projection in the climate change in the Mekong River Basin. Part I: temperature

This paper evaluates the performance of the Coupled Model Intercomparison Project phase 5 (CMIP5) in simulating annual and decadal temperature in the Mekong River Basin from 1950 to 2005. By use of Bayesian multi-model averaging method, the future projection of temperature variation under different scenarios are also analyzed. The results show, the performances of climate model are more accurate in space than time, the model can catch the warming characteristics in the Mekong river Basin, but the accuracy of simulation is not good enough. Bayesian multi-model averaging method can improve the annual and decadal temperature simulation when compared to a single result. The projected temperature in Mekong River will increase by 0.88 °C/100 year, 2.15 °C/100 year and 4.96 °C/100 year for the RCP2.6, RCP4.5, and RCP8.5 scenarios, respectively, over the twenty-first century. The findings will be beneficial for local people and policy-maker to formulate regional strategies against the potential menaces of warming scenarios.     

Spatial and seasonal variations of pesticide contamination in agricultural soils and crops sample from an intensive horticulture area of Hohhot, North-West China

The spatial variability and temporal trend in concentrations of the organochlorine pesticides (OCPs), hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT), in soils and agricultural corps were investigated on an intensive horticulture area in Hohhot, North-West China, from 2008 to 2011. The most frequently found and abundant pesticides were the metabolites of DDT (p,p′-DDE, p,p′-DDT, o,p′-DDT and p,p′-DDD). Total DDT concentrations ranged from ND (not detectable) to 507.41 ng/g and were higher than the concentration of total HCHs measured for the range of 4.84–281.44 ng/g. There were significantly positive correlations between the ∑DDT and ∑HCH concentrations (r ²>0.74) in soils, but no significant correlation was found between the concentrations of OCPs in soils and clay content while a relatively strong correlation was found between total OCP concentrations and total organic carbon (TOC). β-HCH was the main isomer of HCHs, and was detected in all samples; the maximum proportion of β-HCH compared to ∑HCHs (mean value 54%) was found, suggesting its persistence. The α/γ-HCH ratio was between 0.89 and 5.39, which signified the combined influence of technical HCHs and lindane. Low p,p′-DDE/p,p′-DDT in N1, N3 and N9 were found, reflecting the fresh input of DDTs, while the relatively high o,p′-DDT/p,p′-DDT ratios indicated the agricultural application of dicofol. Ratios of DDT/(DDE+DDD) in soils do not indicate recent inputs of DDT into Hohhot farmland soil environment. Seasonal variations of OCPs featured higher concentrations in autumn and lower concentrations in spring. This was likely associated with their temperature-driven re-volatilization and application of dicofol in late spring.     

长江流域养殖池塘氮磷污染负荷估算

长江流域平原区水网密布、渔业发达,养殖池塘造成的氮磷污染问题突出,是河湖富营养化的重要污染源之一;从大空间尺度,精细化估算养殖池塘的氮磷污染负荷,对水污染的精准防控具有重要意义.以长江流域为研究区,依托Google Earth Engine遥感大数据平台,构建了基于机器学习算法的养殖池塘识别模型,精细化识别了长江流域养殖池塘的分布与类型;梳理养殖坑塘的氮磷污染研究案例,针对长江流域养殖坑塘的特征,构建氮磷污染负荷的估算方法,评估氮磷污染负荷的时空分布.研究结果表明：2021年,长江流域养殖池塘总面积为14567km²,包括鱼塘5820 km²、虾蟹塘8747 km²、氮磷排放量分别为95059、16224 t;中部地区的氮磷污染负荷最大,东部地区次之,西部地区最小.本研究是遥感大数据在大尺度污染负荷定量分析的尝试应用,方法适用于其它类型污染负荷的估算.     

废旧电路板制备的酚醛树脂的研究

废旧电路板中的树脂与碳酸钙共同加热,获得气体、固体和热解油3种热解产物.以电路板的热解油为原料、以热解过程中产生的氨气为催化剂,可以合成醇溶性热解油酚醛树脂,经分析测试表明,其组成、结构和固化特征与常规工业生产的氨催化酚醛树脂的性能相近,主要性能指标:粘度、游离酚浓度和胶合强度等均可达到醇溶性酚醛树脂产品的质量要求.     

超声强化Fe0去除阳离子红GTL的研究

采用US/Fe⁰系统去除阳离子红GTL,考察了pH值、Fe⁰用量、超声功率及活性炭、H₂O₂、盐分添加对阳离子红GTL去除率的影响,利用紫外-可见吸收光谱变化查明阳离子红GTL在不同条件下的去除差异性,利用SEM解析铁的形态与染料去除的相关性。结果表明： pH≥5.0时超声和Fe⁰具有协同效应,Fe⁰用量2 g/L,pH=7.0,超声功率135 W,阳离子红GTL去除率达到96.07%;一定量的活性炭、H₂O₂、盐分添加会加速染料去除,US加速Fe⁰反应速度,但不改变染料降解机理,添加活性炭能够彻底降解阳离子红GTL,添加H₂O₂提供的氧化环境抑制苯胺类化合物生成;铁的形态及与染料的接触是影响染料去除效果的重要原因。     

三相流化床中混合载体的协同作用

在侧边沉降的三相气提升流化床反应器中使用粗粒焦炭和细粒石英砂混合构成载体来处理废水具有良好的协同作用。处理焦化废水的实验表明,与单一载体相比,混合载体不易流失;ＣＯＤ容积负荷高达１１ｋｇ／（ｄ·ｍ３）;对酚氰等有害物质的耐冲击能力好;高负荷运行时酚和氰的出水浓度仅为单一载体的１／５－１／３;使用混合型载体还有利于挂膜和降低曝气能耗。