Lead-210 and Beryllium-7 in the Aerosol Particles Around Taiwan Off-Shore Areas

Abstract

Distributions of ²¹⁰Pb and ⁷Be in the aerosol particles of different size fractions were measured around Taiwan offshore areas from October, 1994 to October, 1995. the size distribution and abundance of the aerosol particles showed both spatial and temporal variations. the particle concentrations off northwestern Taiwan were more than twice as those off northeastern Taiwan both in November and March, and the values were much higher in November than in March for both areas. the measured particle concentrations, except for one sample with an unusually high value, ranged from 10 to 83 μOgm ^?3 in the study areas. the ²¹⁰Pb concentrations in the aerosol particles filtered from the air mass varied between 20 × 10^?3 and 72 × 10^?3 dpm m^?3 (1dpm = 0.45 pCi). the ²¹⁰Pb concentrations in the area off southwestern Taiwan appeared somewhat higher than in other areas and were probably contributed by the land air from Taiwan which contains higher ²¹⁰Pb in winter. the ²¹⁰Pb concentrations off northern Taiwan were low in November when the aerosol concentrations were high, but they were high in March when the aerosol concentrations were low.

Based on the ⁷Be monitoring records of 20 years on the aerosol particles of the island by the Taiwan Radiation Monitoring Center, the mean settling rate averaged 0.91, 0.79 and 0.68 cm s^?1, respectively, in northern, central and southern Taiwan. with these values and the ²¹⁰Pb concentrations in the aerosols, the ²¹⁰Pb flux was determined to be between 0.58 and 2.30 dpm cm^?2y^?1, with an average of 1.19 dpm cm^?2y^?1. Excluding the highest value due to its extremely high ²¹⁰Pb and aerosol concentrations, the average is reduced to 1.05 dpm cm^?2y^?1. the activity median diameters (AMD) for ²¹⁰Pb in the study areas were between 0.69 and < 0.49 μM with a mean of 0.5 öm based on ²¹⁰Pb distributions in different particle size fractions. Thus, ²¹⁰Pb was preferentially adsorbed on to the submicron particles. ⁷Be in the study areas showed a good correlation with ²¹⁰Pb in total activity although the two nucides had different sources.     

阴极材料对三相三维电极反应器电解处理酸性橙7的影响研究

采用具有不同阴极材料的三相三维电极反应器,对300 mg/L酸性橙7(AO7)模拟废水进行处理研究,重点考察阴极材料对脱色率和反应体系矿化能力的影响,同时利用HPLC、UV-Vis、GC-MS等分析方法对·OH、H2O2以及降解产物进行测定,探讨了3种电极对AO7的降解行为.结果表明,在电压20 V条件下电解60 min后,活性炭纤维(ACF)、石墨和不锈钢等3种阴极体系对于AO7的脱色率均高于96%,三者之间没有明显差别.但是ACF体系对TOC的去除率可达到57.4%,高于其它两者.3种阴极体系中均有高活性的·OH和H2O2生成,但是ACF阴极体系中产生的浓度较高,从而决定了其具有较高的矿化能力.几种不同电极体系电解AO7过程中都遵循了相同的产生酮类和萘酚类物质的过程.     

双酚AF诱导乳腺癌细胞增殖的分子机制

从细胞水平上研究不同浓度双酚AF （BPAF）对MCF-7人乳腺癌细胞系的细胞增殖能力、细胞凋亡、细胞周期等终点的影响;以新型雌激素膜受体GPER1介导的PI3K/Akt和ERK1/2信号通路为靶点,研究低浓度BPAF对该信号通路相关基因表达的影响,以及其在诱导乳腺癌细胞增殖中的作用,评估其增殖效应机制.结果表明,低浓度BPAF （0.001~1μmol/L）能够诱导MCF-7细胞的增殖,使S期细胞比例升高,并且激活雌激素信号通路相关基因mRNA的表达;在较高浓度时（>10μmol/L）能抑制细胞活力,诱导细胞凋亡.通过特异性靶点抑制剂发现GPER1在mRNA层面上激活了PI3K/Akt和ERK1/2信号通路,并且该信号通路的激活可能是BPAF引起MCF-7细胞增殖的关键机制,并且ERα也在其中起到了重要的作用.     

Acid Orange 7 degradation using methane as the sole carbon source and electron donor

• AO7 degradation was coupled with anaerobic methane oxidation. • Higher concentration of AO7 inhibited the degradation. • The maximum removal rate of AO7 reached 280 mg/(L·d) in HfMBR. • ANME-2d dominated the microbial community in both batch reactor and HfMBR. • ANME-2d alone or synergistic with the partner bacteria played a significant role. Azo dyes are widely applied in the textile industry but are not entirely consumed during the dyeing process and can thus be discharged to the environment in wastewater. However, azo dyes can be degraded using various electron donors, and in this paper, Acid Orange 7 (AO7) degradation performance is investigated using methane (CH₄) as the sole electron donor. Methane has multiple sources and is readily available and inexpensive. Experiments using ¹³C-labeled isotopes showed that AO7 degradation was coupled with anaerobic oxidation of methane (AOM) and, subsequently, affected by the initial concentrations of AO7. Higher concentrations of AO7 could inhibit the activity of microorganisms, which was confirmed by the long-term performance of AO7 degradation, with maximum removal rates of 8.94 mg/(L·d) in a batch reactor and 280 mg/(L·d) in a hollow fiber membrane bioreactor (HfMBR). High-throughput sequencing using 16S rRNA genes showed that Candidatus Methanoperedens, affiliated to ANME-2d, dominated the microbial community in the batch reactor and HfMBR. Additionally, the relative abundance of Proteobacteria bacteria (Phenylobacterium, Pseudomonas, and Geothermobacter) improved after AO7 degradation. This outcome suggested that ANME-2d alone, or acting synergistically with partner bacteria, played a key role in the process of AO7 degradation coupled with AOM.     

RESOLUTION OF ENDANGERED SPECIES ACT ISSUES IN PERMITTING TILE PLATEAU CREEK PIPELINE1

ABSTRACT: This paper describes how a hydrologic model proved to be a valuable tool to help interested parties understand impacts to four threatened and endangered fish species in the Upper Colorado River. In 1994, the Ute Water Conservancy District initiated permitting and design of the Plateau Creek pipeline replacement. The project was considered a major Federal action and therefore subject to the National Environmental Policy Act. Under Section 7 of the Endangered Species Act, the U.S. Fish and Wildlife Service (USFWS) entered the process to develop a Biological Opinion (BO) and determined that the project could potentially impact the endangered fish in the 15‐mile reach of the Colorado River. The Section 7 consultation was directed by a Core Committee comprised of stakeholders in the Upper Colorado River watershed. Hydrologic modeling became the evaluation tool for comparing flow reductions to USFWS target recovery flows and defining make‐up flow requirements to meet those targets. The Colorado River Recovery Implementation Program was designated to provide the make‐up flows. The USFWS released a final BO in December 1997, approving diversions through 2015. An Environmental Impact Statement for the project was completed and the Record of Decision was issued by the Bureau of Land Management in early 1998.     

Sex pheromone of <Emphasis Type="Italic">Ectinus aterrimus</Emphasis> (L<Emphasis Type="SmallCaps">inné</Emphasis>, 1761) (Coleoptera: Elateridae)

Summary.   Ectinus aterrimus (L.) is a fairly common European click beetle species which develops mainly in forests. In pheromone gland extracts of female E. aterrimus, examined using gas chromatography – mass spectrometry (GC-MS), one single compound was present. This was identified as 7-methyloctyl 9-methyldecanoate by comparison with a synthetic sample. Field trapping trials revealed a highly significant attraction of male E. aterrimus towards this ester. The structure of the compound differs remarkably from the pheromones of the closely related Agriotes spp., which exclusively use terpene esters.     

高强预腐蚀铝合金单轴拉-拉疲劳断口定量分析

目的通过断口定量分析获得7A09铝合金的疲劳裂纹扩展规律,为7A09铝合金结构的寿命评估提供依据。方法使用EXCO溶液对试验件进行预腐蚀,利用疲劳拉伸机进行疲劳加载直至断裂,使用扫描电镜对疲劳断口进行定量化分析。结果疲劳裂纹在试件的腐蚀坑处萌生,从自由界面附近向纵深发展导致试件的断裂。通过断口分析和Paris公式确定了裂纹的萌生寿命和扩展寿命。结论腐蚀之后的试件裂纹萌生寿命占总寿命的比例下降,当裂纹扩展程度较大之后,受腐蚀影响减轻,得出裂纹扩展速率和应力强度因子的关系。     

7B04铝合金海洋性大气腐蚀研究

通过在青岛和海南开展的7B04铝合金户外大气暴露试验,利用失重分析、形貌观察、断面分析和电化学交流阻抗谱等研究了7B04铝合金在海洋性大气环境中的腐蚀动力学规律和腐蚀特征。结果表明,在青岛和海南等海洋性大气环境中,7B04铝合金腐蚀初期以点蚀形式萌生,随后向均匀腐蚀发展;腐蚀过程均经历了腐蚀速率由高到低的过程,且腐蚀失重与时间的关系均可用幂函数显著回归;电化学阻抗谱分析表明当腐蚀产物足够厚时,7B04铝合金海洋性大气腐蚀的电化学过程由侵蚀性离子的扩散步骤来控制。     

邻苯二甲酸酯类雌激素活性联合作用模型分析

环境雌激素对生命健康影响受到广泛关注,现行污染物环境标准制订和风险评价只针对单一化合物而非混合物效应,不足以保护生命安全与人类健康。为探讨环境雌激素的混合物效应,选择对雌激素敏感的人乳腺癌MCF-7细胞增殖实验,检测雌二醇(E2)、邻苯二甲酸酯类化合物(DBP和DEHP)的单一及其联合雌激素活性;基于单一化合物的浓度-反应曲线,运用浓度相加(CA)和独立作用(IA)模型对混合物的毒性进行预测,并将模型预测结果与混合物实验数据进行比较分析。结果表明,E2、DBP、DEHP对MCF-7细胞的单一作用数据可通过Weibull方程拟合,由拟合方程得到的半数效应浓度(EC50)及95%置信区间分别为3.450×10-6(2.373×10-6~1.675×10-5)、5.138(1.489~1.082×10)、1.186(4.478×10-1~2.24)μmol·L-1;3种化合物的混合物数据亦可通过Weibull、Logistic和Exp Gro1方程进行有效拟合,混合物效应与化合物单独作用产生的效应具有显著性差异;3种化合物表现非相似联合作用,利用独立作用(IA)模型预测混合物效应较为可靠,外源性环境雌激素与内源性雌激素联合作用产生的混合效应显著。环境雌激素混合物毒性可以通过相加作用模型预测,为环境复合污染的风险评价和管理提供基础数据。     

Scaling range sizes to threats for robust predictions of risks to biodiversity

Assessments of risk to biodiversity often rely on spatial distributions of species and ecosystems. Range‐size metrics used extensively in these assessments, such as area of occupancy (AOO), are sensitive to measurement scale, prompting proposals to measure them at finer scales or at different scales based on the shape of the distribution or ecological characteristics of the biota. Despite its dominant role in red‐list assessments for decades, appropriate spatial scales of AOO for predicting risks of species’ extinction or ecosystem collapse remain untested and contentious. There are no quantitative evaluations of the scale‐sensitivity of AOO as a predictor of risks, the relationship between optimal AOO scale and threat scale, or the effect of grid uncertainty. We used stochastic simulation models to explore risks to ecosystems and species with clustered, dispersed, and linear distribution patterns subject to regimes of threat events with different frequency and spatial extent. Area of occupancy was an accurate predictor of risk (0.81<|r|<0.98) and performed optimally when measured with grid cells 0.1–1.0 times the largest plausible area threatened by an event. Contrary to previous assertions, estimates of AOO at these relatively coarse scales were better predictors of risk than finer‐scale estimates of AOO (e.g., when measurement cells are <1% of the area of the largest threat). The optimal scale depended on the spatial scales of threats more than the shape or size of biotic distributions. Although we found appreciable potential for grid‐measurement errors, current IUCN guidelines for estimating AOO neutralize geometric uncertainty and incorporate effective scaling procedures for assessing risks posed by landscape‐scale threats to species and ecosystems.