Quantifying construction and demolition waste: An analytical review

Quantifying construction and demolition (C&D) waste generation is regarded as a prerequisite for the implementation of successful waste management. In literature, various methods have been employed to quantify the C&D waste generation at both regional and project levels. However, an integrated review that systemically describes and analyses all the existing methods has yet to be conducted. To bridge this research gap, an analytical review is conducted. Fifty-seven papers are retrieved based on a set of rigorous procedures. The characteristics of the selected papers are classified according to the following criteria - waste generation activity, estimation level and quantification methodology. Six categories of existing C&D waste quantification methodologies are identified, including site visit method, waste generation rate method, lifetime analysis method, classification system accumulation method, variables modelling method and other particular methods. A critical comparison of the identified methods is given according to their characteristics and implementation constraints. Moreover, a decision tree is proposed for aiding the selection of the most appropriate quantification method in different scenarios. Based on the analytical review, limitations of previous studies and recommendations of potential future research directions are further suggested.     

Factors associated with financial support in old age for young and middle-aged rural residents in China

This study examined the factors associated with financial support in old age from three primary mechanisms-personal savings,family support,and social insurance-to explore the implications for the future development of China’s rural social welfare system.Cross-sectional surveys of 1392 young and middle-aged rural residents were conducted in July and August2012.The results showed that while social insurance was increasingly acceptable,personal savings and family support still had fundamental value.Combining the three mechanisms,the rural old-age welfare system presented nontraditional features.China’s new rural endowment insurance is discussed as a means to address the need for financial support among the rural aging population.     

Application of hinokitiol potassium salt for wood preservative

The decay of wood and other cellulosic materials by fungi cause significant economic loss. The widely used chromated copper arsenate was prohibited for the environmental impact and safety of arsenic and chromium. It was found that natural product hinokitiol (HK) had fungicidal and insecticidal activities, and its toxicity was bearable for the environment. We described the practical synthesis of HK-K salt. According to the GB/T18261-2000 and LY/T1283-1998, wood preservative performance of HK-K salt was tested. The results showed that the best inhibitory concentration of HK-K salt was 50 mg/L, for which the prevention effectiveness on mold is better, the killed value is between 0 and 1, and the corrosion-resistant for wood-rotting fungi is grade A.     

Influence of fuel moisture, charge size, feeding rate and air ventilation conditions on the emissions of PM, OC, EC, parent PAHs, and their derivatives from residential wood combustion

Controlled combustion experiments were conducted to investigate the influence of fuel charge size, moisture, air ventilation and feeding rate on the emission factors (EFs) of carbonaceous particulate matter, parent polycyclic aromatic hydrocarbons (pPAHs) and their derivatives from residential wood combustion in a typical brick cooking stove. Measured EFs were found to be independent of fuel charge size, but increased with increasing fuel moisture. Pollution emissions from the normal burning under an adequate air supply condition were the lowest for most pollutants, while more pollutants were emitted when an oxygen deficient atmosphere was formed in the stove chamber during fast burning. The impacts of these factors on the size distribution of emitted particles was also studied. Modified combustion efficiency and the four investigated factors explained 68%, 72%, and 64% of total variations in EFs of PM, organic carbon, and oxygenated PAHs, respectively, but only 36%, 38% and 42% of the total variations in EFs of elemental carbon, pPAHs and nitro-PAHs, respectively.     

凹凸棒石处理石油污染地下水的影响因素研究

选取某石油类污染地区为对象,研究地下水阴阳离子浓度不同时凹凸棒石净化石油烃污染地下水的效率,为下一步的PRB修复工作做准备。结论表明:凹凸棒石经过热处理改性后,可提高去除污染地下水中石油烃的能力,凹凸棒石的最佳热处理温度为130℃。除Na+对凹凸棒石净化石油烃去除率在低浓度有抑制作用外,其他离子均在低浓度时对去除率有促进作用,在高浓度时对去除率有抑制作用。     

基于环境监管平台的脱硫烟气SVR模型及优化

基于环境监管平台建立脱硫烟气SVR预测模型,通过Pearson系数、经验公式选择特征,利用网格寻参(gridsearch)、遗传算法(GA)以及粒子群优化算法(PSO)在5-fold交叉验证下对该模型优化、训练并预测。误差分析和比较表明SVR模型预测能力较高,遗传算法优化适应于此类数据训练,且SVR模型对于机组有依赖性。     

北京嘉泰国际大厦空调机房噪声治理

北京嘉泰国际大厦因在建筑设计和施工阶段未对空调机房采用合理的噪声控制措施,导致竣工后噪声达不到用户的要求,无法使用。只能花更大的精力和代价进行改造和治理。以此为实例,分析其噪声振动超标的原因,并简述治理方案及最终效果。最后提出大厦机房建造和振动噪声控制方面的建议。     

Suppressing SO3 formation in copper smelting flue gas by ejecting pyrite into flue

Environmental Science and Pollution Research - SO3 in the copper smelting flue gas not only causes serious corrosion in heat exchange and dust collection equipment but also increases the amount of...     

某油田采出水用杀菌剂急性毒性研究与职业病防护建议

目的:对某油田采出水用杀菌剂毒性进行评价,为员工安全操作及职业病防护提供依据。方法:采用动物试验方法,对某油田采出水用杀菌剂进行急性毒性实验研究。结果:该油田采出水用杀菌剂对SD大鼠的急性经口半数致死剂量(LD 50)为3160 mg/(kg·bw),属实际无毒级;对普通级成年新西兰白兔皮肤为中等刺激性,对眼睛为严重眼损伤/对眼造成不可逆影响;对普通级白化豚鼠皮肤为低致敏性。结论:该油田采出水用杀菌剂对皮肤、眼睛可能存在较大损伤,作业人员进行相关作业时应做好防护。     

绿色金融改革政策的碳减排效应

以绿色金融改革创新试验区政策为例,基于2013~2019年间我国280个地级市的面板数据,运用双重差分法识别绿色金融改革政策是否具有碳减排效应以及其作用机制.研究发现,绿色金融改革政策具有显著碳减排效应（平均值为-0.375）,且呈现逐年递增.机制分析发现,绿色金融改革政策主要通过降低能源消耗强度、提升绿色技术创新水平发挥碳减排效应.此外,绿色金融改革政策具有正向溢出效应,绿色金融改革政策的碳减排效应会辐射到试点区域的周边地区.但绿色金融改革政策并未发挥多污染物减排协同效应.基于此,本文提出了扩大改革试验区范围、加大对绿色金融主体的激励和引导以及发挥绿色金融政策协同效应等政策建议.