危险废物焚烧飞灰中重金属的稳定化处理

以上海市某危险废物焚烧厂飞灰为研究对象,采用Na2S、FeSO4、Na3PO4、和Na3C3N3S34种不同类型化学稳定药剂对飞灰进行了稳定化处理,并应用XRD、IR、SEM和连续化学提取法等仪器和手段对Na3C3N3S3处理焚烧飞灰的产物进行分析研究。研究结果表明,Na3C3N3S3对飞灰中的重金属Cr、Pb、Zn的稳定效果最好,Na3PO4对Cr无明显稳定效果。稳定后产物表面变得致密化,Na3C3N3S3与重金属离子生成的沉淀物干燥后无明显晶型存在。经稳定处理后飞灰中的重金属形态由弱酸提取态转化为可氧化态,减少了飞灰中重金属的浸出毒性。     

木质素磺酸盐在微生物燃料电池中的降解及产电性能研究

以厌氧活性污泥为接种体构建铁氰化钾阴极微生物燃料电池(MFC),对木质素磺酸盐的降解及产电效果进行了研究。结果表明,经过6个周期逐渐添加木质素磺酸盐的驯化后,以木质素磺酸盐为单一底物的MFC成功运行,最大功率密度为120.3 mW/m2。经过94 h的运行,阳极液COD和木质素磺酸盐去除率分别达到39.8％和49.3％...     

Calcium amendment improved the performance of fragrant rice and reduced metal uptake under cadmium toxicity

Environmental Science and Pollution Research - Cadmium (Cd) toxicity has detrimental effects on plant metabolism and yield formation. This study examined the effects of Cd stress in rice and the...     

Effect of technology development on potential environmental impacts from heavy metals in waste smartphones

Technology development has brought beneficial changes in the functions of smartphones but has the potential to impact the environment due to the high generation of waste smartphones. Thus, this study evaluates and compares environmental impact potentials from metals in waste smartphones to figure out the effect of smartphone model replacements on hazardous waste, resource depletion, and toxicity potentials. The total threshold limit concentration (TTLC) analysis is used to determine whether the waste smartphones would be classified as hazardous waste, and the life-cycle impact assessment methods are used to evaluate resource depletion, cancer, non-cancer, and ecotoxicity potentials. The TTLC results showed that the smartphone technology development did not reduce hazardous waste potentials. The life-cycle impact assessment results showed that the technology development overall reduced resource depletion potential but increased toxicity potential. In addition, priority metals contributing to the potentials were identified to effectively manage their environmental impacts. This study can provide fundamental information for smartphone manufacturers, waste smartphone recyclers and disposers, and e-waste policymakers to circulate resources and to prevent environmental pollutions from hazardous and toxic materials.     

News sentiment to market impact and its feedback effect

Although market feedback on investor sentiment effect has been conceptually identified in the existing finance literature and investment strategies have been designed to explore this effect, there lacks systematic analysis in a quantified manner on such effect. Digitization of news articles and the advancement of computational intelligence applications have led to a growing influence of news sentiment over financial markets in recent years. News sentiment has often been used as a proxy for gauging investor sentiment and reflecting the aggregate confidence of the society toward future market. Previous studies have primarily focused on elucidating the unidirectional impact of news sentiment on market returns and not vice versa. In this study, we analyze more than 12 millions of news articles and document the presence of a significant feedback effect between news sentiment and market returns across the major indices in the US financial market. More specifically, we find that news sentiment exhibits a lag-5 effect on market returns and conversely market returns elicit consistent lag-1 effects on news sentiment. This aligns well with our intuition that news sentiment drives trading activity and investment decisions. In turn, heightened investment activity further stimulates involuntary responses, which manifest in the form of more news coverage and publications. The evidence presented highlights the strong correlation between news sentiment and market returns and demonstrates the benefits of advancing knowledge in data-driven modeling and its interaction with market movements.     

The use of food wastes as feed ingredients for culturing grass carp (<Emphasis Type="Italic">Ctenopharyngodon idellus</Emphasis>) in Hong Kong

Different types of food wastes, e.g., meats, bones, cereals, fruits, and vegetables, were collected from hotels in Hong Kong, mixed in different ratio, and processed into feed pellets (food wastes (FWs) A, B, and C) for feeding trials in aquaculture species. Grass carp fed with cereal-dominant feed (FW A) showed the best growth (in terms of specific growth rate, relative weight gain, and protein efficiency ratio), among all food waste feeds. However, the growth rates of food waste groups especially the meat product-contained feeds (FW B and FW C) were lower than the commercial feed, Jinfeng^® 613 formulation (control). The results indicated that grass carp utilized plant proteins better than animal proteins and preferred carbohydrate as a major energy source than lipid. The high-lipid content in feed containing meat products was also a possible reason for hindering growth and resulted high body lipid. It is suggested that lipid should be removed in the preparation of food waste feed or further investigations by implementing supplements, e.g., enzymes in feed to enhance lipid or protein utilization by fish. This utilization of food waste could be an effective and practical way to deal with these wastes in this densely populated city.     

Preparation,characterization, and photocatalytic activity evaluation of Fe–N-codoped TiO2/fly ash cenospheres floating photocatalyst

Nitrogen-doped titanium dioxide (TiO₂) and Fe–N-codoped TiO₂ layers on fly ash cenospheres (FAC) as floating photocatalyst were successfully prepared through sol–gel method. Photocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), ultraviolet (UV)–Vis diffuse reflectance spectroscopy (DRS), and nitrogen adsorption analyses for Brunauer–Emmett–Teller (BET) specific surface area. Photocatalytic efficiency of the prepared catalyst was evaluated through using the decomposition of Rhodamine B (RhB) as a model compound under visible light irradiation. Photocatalytic activity and kinetics of catalyst under visible light were detected in details from different Fe/Ti mole ratios by detecting photodegradation of RhB. Experimental results show that when the calcination temperature was 550 °C, the dosage of FAC was 3.0 g, and the mole ratio of Fe/Ti was 0.71 %; the synthesized Fe–N-TiO₂/FAC photocatalyst presented as anatase phase and that N and Fe ions were doped into TiO₂ lattice. The material’s specific surface area was 34.027 m²/g, and UV–Vis diffuse reflectance spectroscopy shows that the edge of the photon absorption has been red shifted up to 400–500 nm. Fe–N-codoped titanium dioxide on FAC had excellent photocatalytic activity during the process of photodegradation of RhB under visible light irradiation.

     

环境水质自动监测系统建设与运行管理

结合山东省环境水质自动监测系统的实际,就环境水质自动监测系统的建设、运行、管理等核心问题进行研究,提出了智能化、实用性、统一性相结合的系统集成方案和监控平台建设整体设计思路,分析了实行社会化、专业化、规模化运营的必要性,从完善监管机制、严格绩效考核、科学审核数据三方面探讨了系统监督管理模式,例证了自动监测数据在环境管理工作中的全面应用。     

Potential of different species for use in removal of DDT from the contaminated soils

Dichlorodiphenyltrichloroethane (DDT) and its main metabolites, p,p'-DDD and p,p'-DDE (DDTs in this study included DDT, DDD and DDE), are frequently detected in agricultural soils even though its usage in agriculture was banned in 1980s or earlier. In this study, eleven plants including eight maize (Zea mays) cultivars and three forage species (alfalfa, ryegrass and teosinte) widely cultivated in China were grown in the soils spiked with DDTs to investigate their potential for removal of DDT from the contaminated soils. The plants varied largely in their ability to accumulate and translocate DDTs, with the bioconcentration factor (BCF; DDT concentration ratio of the plant tissues to the soils) ranging from 0.014 to 0.25 and the translocation factor (TF; DDT concentration ratio of the shoots to the roots) varying from 0.35 (Zea mays cv Chaotian-23) to 0.76 (Zea mays spp. mexicana). The amount of DDT phytoextraction ranged from 3.89mug (ryegrass) to 27.0mug (teosinte) and accounted for <0.1% of the total initial DDTs spiked in the soils. After 70d, the removal rates reached 47.1-70.3% of the total initial DDTs spiked in the soils with plants while that was only 15.4% in the soils without plant. Moreover, the higher removal rates of DDTs occurred at the first 20d of experiment, and then the removal rate decreased with time. The highest amount of DDTs phytoextracted was observed in teosinte, followed by Zea mays spp. mexicana, but the highest removal rate of DDTs was found in maize (Zea mays cv Jinhai-6). Even though phytoextraction is not the main removal process for DDTs, the plant species especially Zea mays cv Jinhai-6 showed high potential for removing DDTs from the contaminated soils.     

中国排污权有偿使用定价及政策影响研究

排放配额的价格是排污权有偿使用政策的关键要素之一。本研究从分析排污权有偿使用政策的内涵出发,厘清有偿使用政策与已有排污收费政策的区别,排污收费是企业为污染物排放造成对环境损害而支付的补偿,而有偿使用费是企业为污染物排放占用环境容量资源支付的稀缺租金。本研究同时考虑了现行排污收费政策和总量控制政策的影响,基于最优化控制理论建立了COD和NH_3-N两种水污染物为独立变量的价格模型,并对有偿使用政策执行后可能带来的影响进行了模拟预测。