Nanoparticles in wastewater from a science-based industrial park - coagulation using polyaluminum chloride

The Hsinchu Science-based Industrial Park (HSIP) is the hi-tech manufacturing hub of Taiwan. Wastewater from the HSIP contains numerous nano-sized silicate particles whose size distributions peak at 2 and 90 nm. A 3-5 mg l(-1) as Al dose of polyaluminum chloride (PACl) was used in the field to coagulate these particles, but the removal efficiency was low. Laboratory scale tests indicated that although PACl coagulation removed 52% of the turbidity and 48% of the chemical oxygen demand (COD) from water, its effect on nano-particle removal was minimal. About 58% of the soluble COD was associated with colloidal Si particles. A light scattering test and transmission electron microscopy (TEM) demonstrated that the nano-particles agglomerated in approximately linear aggregates of sizes 100-300 nm. Prolonged contact between residual PACl and the nano-particles generated large aggregates with sizes of up to 10 microm and a fractal dimension of 2.24-2.63. The results presented herein should be of interest in the processing of "high-tech" wastewater that contains nanosized silica particles.     

典型的固定源排放可凝结颗粒物中无机组分研究

近年来我国各类典型固定源排放可过滤颗粒物（Filterable Particulate Matter,FPM）的水平已经明显降低,然而固定源可凝结颗粒物（Condensable Particulate Matter,CPM）的排放水平却逐渐引起人们的关注和重视.因此研究不同类型固定源CPM的排放特征对进一步了解和控制固定源颗粒物的排放具有重要意义.本研究根据美国EPA Method 202搭建了一套CPM的采样装置,对5个不同固定源排放的CPM进行了采样.实验结果表明在两个燃煤电厂、一个烧结厂和两个垃圾焚烧厂中,CPM的排放浓度分别为 7.65、26.00、28.89、6.82和5.53 mg·m^-3,无机组分在CPM中的占比分别为69%、62%、43%、62%和71%.其中SO₄^2-是燃煤电厂和烧结厂排放CPM中最主要的水溶性离子,占总离子的67%以上.Cl^-是垃圾焚烧厂排放CPM中最主要的水溶性离子,占总离子的37%以上.K、Ca、Na、Fe、Mg和Al等元素在各类固定源CPM排放的总元素中占比较高,大约在80%以上.此外,在燃煤电厂和烧结厂排放CPM中的未知组分比例大约在20%以上,说明现阶段我们对CPM组成成分的研究还有限,未来应当继续探索研究.     

设施菜地土壤重金属累积及影响因素研究

为了解设施菜地土壤重金属累积规律及影响因,通过在全国8个省具有代表性的设施蔬菜产区采集土壤和肥料样品,系统研究了设施栽培年限、肥料施用、土壤性质对设施菜地土壤重金属Cu、Zn、Cd累积量及活度的影响.结果表明:与露天栽培相比,设施条件下随着栽培年限的延长,土壤Cu、Zn和Cd的全量和有效态浓度均呈明显的累积趋势,栽培年限>15a时的设施土壤Cu、Zn和Cd的全量和有效态浓度分别是露天栽培土壤的1.57、2.16、1.67、3.28、1.96、2.00倍.Pearson分析表明设施菜地土壤Cu、Zn、Cd均与土壤SOM呈极显著相关,说明其在来源上较强的相似性,进一步对设施栽培土壤主要投入品中Cu、Zn、Cd含量分析表明,猪粪、商品有机肥及土壤调理剂中Cu、Zn均超过了100mg/kg,Cd超过了1.0mg/kg,且投入量较大,是设施栽培土壤中Cu、Zn、Cd的主要贡献者,而秸秆和部分化肥(如尿素、硫酸钾)中的Cu、Zn、Cd含量均极低,对设施栽培土壤累积贡献微乎其微.pH值和CEC是影响Cu、Zn、Cd在土壤中累积活度的关键因素,其中随着pH值的升高土壤Cu活度表现了先升高后下降的趋势,而土壤Cd活度则表现了持续下降的趋势,仅在pH<6.26时达到了显著相关水平;土壤CEC的升高对土壤Cu活度表现了先下降后升高再下降的趋势,土壤Cd活度表现了先升高后缓慢下降再升高的趋势,而土壤Zn活度仅在CEC<5.83时随着CEC升高表现下降显著线性相关趋势.因此,防止设施栽培土壤Cu、Zn、Cd的累积与污染,选择重金属含量低的肥料和调控土壤理化特性(尤其是pH值、CEC)则是缓解设施栽培土壤重金属累积速率进而确保蔬菜质量安全的有效途径.     

Increased risk of preterm delivery among people living near the three oil refineries in Taiwan

The petrochemical and petroleum industries are two of the main sources of industrial air pollution in Taiwan. Data used in this study concern outdoor air pollution and the health of individuals living in communities in close proximity to oil refinery plants. The prevalence of delivery of preterm birth infants was significantly higher in mothers living near the oil refinery plants than in control mothers in Taiwan. After controlling for several possible confounders (including maternal age, season, marital status, maternal education, and infant sex), the adjusted odds ratio was 1.14 (95% CI=1.01-1.28) for delivery of preterm infants for mothers living near oil refinery plants. These data provide further support for the hypothesis that air pollution can affect the outcome of pregnancies.     

河口-近海环境新污染物的环境过程、效应与风险

在全球变化和人类活动双重影响下,大量陆源污染物特别是备受各国政府和民众关注的微塑料、新型持久性有机污染物以及药物和个人护理品等新污染物进入水体环境并迁移扩散,对近海生态环境安全和人体健康产生了巨大影响.综述国内外微塑料、全/多氟化合物、抗生素和内分泌干扰物等新污染物在河口-近海环境中的污染来源、时空分布和迁移传输等环境过程及其影响因素,分析探讨近海水生生态系统中新污染物产生的不良生态效应和风险,提出未来研究重点应关注河口-近海环境中多种新污染物的相互作用和新污染物产生的联合生态毒理效应及造成的生态和健康风险等,为陆海统筹下的海洋污染防治和海洋经济的健康发展提供科学依据.     

Managing Protected Areas Under Climate Change: Challenges and Priorities

The implementation of adaptation actions in local conservation management is a new and complex task with multiple facets, influenced by factors differing from site to site. A transdisciplinary perspective is therefore required to identify and implement effective solutions. To address this, the International Conference on Managing Protected Areas under Climate Change brought together international scientists, conservation managers, and decision-makers to discuss current experiences with local adaptation of conservation management. This paper summarizes the main issues for implementing adaptation that emerged from the conference. These include a series of conclusions and recommendations on monitoring, sensitivity assessment, current and future management practices, and legal and policy aspects. A range of spatial and temporal scales must be considered in the implementation of climate-adapted management. The adaptation process must be area-specific and consider the ecosystem and the social and economic conditions within and beyond protected area boundaries. However, a strategic overview is also needed: management at each site should be informed by conservation priorities and likely impacts of climate change at regional or even wider scales. Acting across these levels will be a long and continuous process, requiring coordination with actors outside the “traditional” conservation sector. To achieve this, a range of research, communication, and policy/legal actions is required. We identify a series of important actions that need to be taken at different scales to enable managers of protected sites to adapt successfully to a changing climate.     

Experimental Evaluation of the Sustainability of Dwarf Bamboo (Pseudosasa usawai) Sprout-Harvesting Practices in Yangminshan National Park,Taiwan

Sustainable harvest of natural products that meets the needs of local people has been viewed by many as an important means for sustaining conservation projects. Although plants often respond to tissue damage through compensatory growth, it may not secure long-term sustainability of the populations because many plants enhance individual well-being at the expense of propagation. Sustainability may further be threatened by infrequent, large-scale events, especially ill-documented ones. We studied the impacts of sprout harvesting on sprout growth in a dwarf bamboo (Pseudosasa usawai) population that has seemingly recovered from an infrequent, large-scale masting event. Experimental results suggest that although a single sprout harvest did not significantly alter the subsequent abundance and structure of sprouts, culm damage that accompanied sprout harvesting resulted in shorter, thinner, and fewer sprouts. Weaker recovery was found in windward, continually harvested, and more severely damaged sites. These findings suggest that sprout growth of damaged dwarf bamboos is likely non-compensatory, but is instead supported through physiological integration whose strength is determined by the well-being of the supplying ramets. Healthy culms closer to the damage also provided more resources than those farther away. Sustainable harvesting of sprouts could benefit from organized community efforts to limit the magnitude of culm damage, provide adequate spacing between harvested sites, and ensure sufficient time interval between harvests. Vegetation boundaries relatively resilient to infrequent, large-scale events are likely maintained by climatic factors and may be sensitive to climate change. Continual monitoring is, therefore, integral to the sustainability of harvesting projects.     

Recycling thin film transistor liquid crystal display (TFT-LCD) waste glass produced as glass–ceramics

The waste electrical and electronic equipment (WEEE) directives are designed to deal with the rapidly increasing waste stream comprised of electrical and electronic equipment. Recycling electrical and electronic equipment reduces the quantity of waste going to final disposal. The demand for thin film transistor liquid crystal display (TFT-LCD) panels, commonly used in everyday electronic products, is increasing. Conventionally adopted treatments of TFT-LCD waste glass cannot meet WEEE directives. This study adopts the following operating conditions in fabricating glass–ceramics: sintering temperature of 800–950 °C; sintering time of 6 h; and, temperature increase rate of 5 °C/min. The glass–ceramic samples then underwent a series of tests, including the Vickers hardness, water absorption and porosity tests, to determine product quality. The Vickers hardness was 12.1 GPa when fired at 900 °C for 6 h, and density was 2.4 g/cm³ and water absorption was 0%. Thus, TFT-LCD waste glass can be regarded as a good glass–ceramic material.     

Remediation of Soil Contaminated with Pyrene Using Ground Nanoscale Zero-Valent Iron

Abstract

The sites contaminated with recalcitrant polycyclic aromatic hydrocarbons (PAHs) are serious environmental problems ubiquitously. Some PAHs have proven to be carcinogenic and hazardous. Therefore, the innovative PAH in situ remediation technologies have to be developed instantaneously. Recently, the nanoscale zero-va-lent iron (ZVI) particles have been successfully applied for dechlorination of organic pollutants in water, yet little research has investigated for the soil remediation so far. The objective in this work was to take advantage of nanoscale ZVI particles to remove PAHs in soil. The experimental factors such as reaction time, particle diameter and iron dosage and surface area were considered and optimized. From the results, both microscale and nanoscale ZVI were capable to remove the target compound. The higher removal efficiencies of nanoscale ZVI particles were obtained because the specific surface areas were about several dozens larger than that of commercially microscale ZVI particles. The optimal parameters were observed as 0.2 g iron/2 mL water in 60 min and 150 rpm by nanoscale ZVI. Additionally, the results proved that nanoscale ZVI particles are a promising technology for soil remediation and are encouraged in the near future environmental applications. Additionally, the empirical equation developed for pyrene removal efficiency provided the good explanation of reaction behavior. Ultimately, the calculated values by this equation were in a good agreement with the experimental data.     

火焰原子吸收光度法测定水中铝的方法改进

研究了在盐酸介质中，壬基酚聚氧乙烯-7醚（NP-7）活化下，火焰原子吸收光度法测定环境水体中铝的方法改进。在25mL容量瓶中，加入5．0mL体积分数为50％的盐酸、2．0mL质量浓度为0．01g／mL NP-7和4．0mL质量浓度为75．0μg/mL的铝标准溶液，在原子吸收分光光度计的最佳测定条件下测定吸光度。根据吸光度与铝质量浓度绘制了工作曲线，线性范围3．0～24．0μg/mL，检出限1．32μg/mL。该法用于环境水体中铝含量的测定，加标回收率为94．4％～101．4％，最大相对标准偏差5．8％，方法对比最大相对误差4．1％。