政府-企业-居民协同共治的道路交通碳交易机制

根据道路交通碳排放的影响机理,提出同时把上游燃料供应企业、中游汽车生产企业、下游汽车使用者同时作为道路交通碳交易的责任主体,设计了政府-企业-居民协同共治的道路交通碳交易机制,包括碳配额总量设定、初始碳配额分配、行业基准设定、履约考核、市场交易以及监测报告核查等制度.通过案例与情景分析揭示了道路交通碳交易的多主体协同作用机理：在政府对于碳配额总量和行业基准的调控下,燃料供应企业将通过改变燃料成分来降低燃料排放因子;汽车生产企业将通过提高汽车燃油经济性和新能源汽车比例来降低汽车能耗强度;汽车使用者将通过减少车辆行驶里程降低交通需求或者购买使用新能源汽车.本文所提出的政府-企业-居民协同共治的道路交通碳交易机制,可以分别从上游、中游、下游促进道路交通碳排放的3个关键影响因素——燃料排放因子、汽车能耗强度、交通活动需求协同优化,能够有效控制道路交通温室气体排放增长,进而加速“碳达峰”的实现和“碳中和”的转型.     

Volatile organic compounds concentration profiles and control strategy in container manufacturing industry: Case studies in China

Volatile organic compounds (VOCs), important precursors of ozone (O₃) and fine particulate matter (PM_2.5), are the key to curb the momentum of O₃ growth and further reducing PM_2.5 in China. Container manufacturing industry is one of the major VOC emitters, and more than 96% containers of the world are produced in China, with the annual usage of coatings of over 200,000 tons in recent years. This is the first research on the emission characteristics of VOCs in Chinese container manufacturing industry, including concentration and ozone formation potential (OFP) of each species. The result shows that the largest amounts of VOCs are emitted during the pretreatment process, followed by the paint mixing process and primer painting process, and finally other sprays process. The average VOC concentrations in the workshops, the exhausts before treatment and the exhausts after treatment are ranging from 82.67–797.46 , 170–1,812.65 , 66.20–349.63 mg/m³, respectively. Benzenes, alcohols and ethers are main species, which contribute more than 90% OFP together. Based on the emission characteristics of VOCs and the technical feasibility, it is recommended to set the emission limit in standard of benzene to 1.0 mg/m³, toluene to 10 mg/m³, xylene to 20 mg/m³, benzenes to 40 mg/m³, alcohols and ethers to 50 mg/m³, and VOCs to 100 mg/m³. The study reports the industry emission characteristics and discusses the standard limits, which is a powerful support to promote VOCs emission reduction, and to promote the coordinated control of PM_2.5 and O₃ pollution.     

用于柔性板振动控制的压电陶瓷时效损伤性能研究

目的基于压电陶瓷的逆压电效应,以试验和仿真分析的方法研究压电陶瓷对某柔性板试验件振动控制的时效性能,为压电陶瓷如何保持长时间有效参与振动控制提供参考。方法搭建振动主动控制系统,实现柔性板的振动控制,以压电陶瓷驱动电压的降低模拟时效损伤。建立该结构的动力学有限元模型,并进行响应分析,以压电陶瓷产生的驱动力变小来模拟时效损伤。通过测定不同损伤程度的压电陶瓷参与振动控制前后的动响应,得到多种条件下的振动控制效率。结果当所有压电陶瓷的时效损伤程度均达到80%时,对某柔性板试验件的振动控制率降低为初始振动控制率的60.4%。基于试验与分析结果,评估多种条件下的振动控制率,得到了压电陶瓷时效损伤对柔性板振动控制的影响规律。结论压电陶瓷时效损伤对柔性板振动控制的影响可以用有限元仿真来模拟,压电陶瓷的时效损伤程度可通过调节它的驱动电压来进行测试。     

Estimation of Avian Influenza Viruses in Water Environments of Live Poultry Markets in Changsha,China, 2014 to 2018

Food and Environmental Virology - In routine surveillance for avian influenza viruses (AIVs) in the environments of live poultry markets (LPMs), certain samples were positive for AIVs type A while...     

KMnO4-PAC对高原喀斯特湖库DOM的DBPsFP控制

以云贵高原典型喀斯特湖库红枫湖取水口溶解性有机质（DOM）为研究对象,调查不同组合方式下高锰酸钾-聚合氯化铝（KMnO₄-PAC）对消毒副产物的生成潜能（DBPsFP）变化和平均组成分布,并通过红外光谱（FTIR）和三维荧光光谱（3D-EEM）对部分样品进行化学表征,推断其影响机制.结果表明：在0.1,0.2,0.4mg/L KMnO₄投加量下,DBPsFP降低17.5~73%,DOM的卤代活性化学结构和官能团部分被有效钝化;PAC的网捕和卷扫效应使DBPsFP进一步减少27.9~86.1%,组合工艺对DBPs的生成潜能影响大小为：三卤甲烷（THM₄） > 卤乙酸（HAA₉） > 卤乙腈（HAN₄）/卤代酮（HK₂）/三氯硝基甲烷（TCNM）.FTIR的结果表明预氧化后3300cm^-1处的透过率降低,指纹区1000~1300cm^-1处的峰频提升,表明分子中的O-H、COOH和C-O官能团增加,共轭不饱和结构在KMnO₄作用下部分消失.3D-EEM验证了外源有机物（腐殖酸）在DOM中占比随KMnO₄浓度梯度升高而下降,同时类蛋白结构的吸收峰强度增加,说明最终DBPs贡献可能源于DOM中剩余的小分子类蛋白（氨基酸）.     

不同油相微乳液性质及其增溶菲的性能研究

以Tween 80为表面活性剂,正戊醇为助表面活性剂,3种不同的植物油（大豆油、棕仁油、葵花油）作为油相构建微乳相图,探究不同油相对微乳液性质的影响.制备了不同油相与表面活性剂质量比（O/S）的3种植物油基系列微乳液,并对比了它们对菲的增溶效果.结果表明,不同油相对微乳液的成相能力及稀释特性影响较大,其中棕仁油 > 葵花油 > 大豆油.3种油相微乳液在不同含水量下具有相似的电导率变化趋势且均为牛顿型流体.制备的3种植物油基系列微乳液对菲的增溶能力均随体系中油含量的增加而提高,其中大豆油基微乳液对菲的增溶效果最差,而棕仁油微乳液在O/S值为0.1时对菲的增溶效果最好,可达2.18g/L.     

Raman spectroscopy of diesel and gasoline engine-out soot using different laser power

We studied engine-out soot samples collected from a heavy-duty direct-injection diesel engine and port-fuel injection gasoline spark-ignition engine. The two types of soot samples were characterized using Raman spectroscopy with different laser powers. A Matlab program using least-square-method with trust-region-reflective algorithm was developed for curve fitting. A DOE (design of experiments) method was used to avoid local convergence. The method was used for two-band fitting and three-band fitting. The fitting results were used to determine the intensity ratio of D (for “Defect” or “Disorder”) and G (for “Graphite”) Raman bands. It is found that high laser power may cause oxidation of soot sample, which gives higher D/G intensity ratio. Diesel soot has consistently higher amorphous/graphitic carbon ratio, and thus higher oxidation reactivity, compared to gasoline soot, which is reflected by the higher D/G intensity ratio in Raman spectra measured under the same laser power.     

含磷物质与活性炭复配稳定土壤重金属研究

利用含磷物质、活性炭及两者复配组合对污染土壤中的重金属进行稳定化处理,根据稳定效率对稳定剂进行筛选,并分析稳定前后土壤重金属的生物有效性、赋存形态变化。结果表明:经磷矿粉+5%煤基活性炭稳定7 d后,土壤中Pb、Zn、Cu、Cd稳定效率分别达75.85%、61.03%、52.80%、49.92%,土壤重金属的DTPA和PBET生物有效态均降低。BCR形态分级实验表明:该复合稳定剂对土壤重金属的稳定化效应较好,重金属的酸可提取态均有所减少,转化为其他难以分解转移的形态。结果表明,磷矿粉和煤基活性炭可作为资源回收利用,应用于土壤重金属污染修复。     

Screening hydroxyapatite for cadmium and lead immobilization in aqueous solution and contaminated soil: The role of surface area

Hydroxyapatite (HAP) has been widely used to immobilize many cationic metals in water and soils. The specific reason why an increase in the surface area of HAP enhances cadmium (Cd) uptake, but has no effect on lead (Pb) uptake, is not clear. The aim of this study was to determine the factors causing the differences in sorption behavior between Cd and Pb by evaluating HAPs with different surface areas. We synthesized HAPs with two different surface areas, which were characterized by X-ray diffraction, N₂ adsorption, and scanning electron microscopy, and then evaluated them as sorbents for Cd and Pb removal by testing in single and binary systems. The sorption capacity of large surface area HAP (1.85 mmol/g) for Cd in the single-metal system was higher than that of small surface area HAP (0.64 mmol/g), but there were no differences between single- and binary-metal solutions containing Pb. After the Cd experiments, the HAP retained a stable structure and intact morphology, which promotes the accessibility of reactive sites for Cd. However, a newly formed precipitate covered the surface and blocked the channels in the presence of Pb, which reduced the number of potential adsorption sites on HAP for Cd and Pb. Remediation experiments using Cd- and Pb-contaminated soil produced similar results to the solution tests. These results indicate that alterations of the structure and morphology during the reaction is an important factor influencing metal sorption to HAP.     

Spatio-temporal variation of landfill gas in pilot-scale semi-aerobic and anaerobic landfills over 5 years

Variation of CH₄, CO₂, and O₂ concentrations in layers of different depths in semi-aerobic and anaerobic landfills was analyzed over a period of 5 years. The results showed that most of the municipal solid waste became basically stable after 5 years of landfill disposal. In the upper and middle layer, the concentration of CH₄ in the semi-aerobic landfill was significantly lower than that in the anaerobic landfill in different landfill periods, while in the lower layer, there was little difference in the CH₄ concentration between the semi-aerobic and anaerobic landfills. The average concentration of CH₄ and CO₂ in the anaerobic landfill was always higher than that in the semi-aerobic landfill, while the O₂ concentration showed an opposite variation in different landfill periods. This was related to the aerobic reaction of landfill waste around the perforated pipe in the semi-aerobic landfill, which inhibited effective landfill gas generation.