氯气事故风险预测评价方法初探

依据区域氯气事故调查的实例研究，求得在不同气象条件下，氯气事故发生的概率。再应用近地面大气污染物扩散模式，预测化工厂液氯钢瓶泄漏事故对周围环境的影响范围及程度，进行环境风险评价。并提出液氯钢瓶外泄事故的防范措施。     

美国海军全舰船电磁脉冲生存能力试验与鉴定研究进展

为了了解美国海军在这一领域取得的研究进展,回顾了近十年来,美国海军在电磁脉冲生存能力试验与鉴定方面所开展的工作,重点介绍和分析了美国海岸警卫队退役快艇"MONHEGAN"号电磁脉冲试验情况、美军标MIL-STD-4023中关于水面舰船电磁脉冲防护及试验要求、美国海军全舰船威胁级电磁脉冲模拟器参数信息及有关舰船电磁脉冲评估的其他试验基础设施资源需求。     

Impact of the 1998 Central American fires on PM2.5 mass and composition in the southeastern United States

The impact of the Central American fires on PM_2.5 mass concentration and composition in the Tennessee Valley region during portions of May, 1998, has been quantified. Elevated concentrations of smoke aerosol tracers—fine potassium, (and to a lesser extent, calcium and silicon) and, where available, organic and elemental carbon—were observed in the region during times in which satellite imagery (TOMS and GOES-8) showed regional transport of hazy, smoky airmasses from southern Mexico and adjacent areas of Central America. Back-trajectories from network sites in the Tennessee Valley network were consistent with this regional transport. The extent of transport of extra-regional fine particle mass during May, 1998, is discussed relative to the new US fine particle mass-based standards for fine particulate matter.     

生物技术在欧美遇到的抵制及教训

回顾了欧美公众对生物技术的种种疑虑和生物技术的研究开发所遇到的阻力，分析了产生这种现象的原因，并提出了我国应从中吸取的教训。     

Neoliberal Style,the American Re-Generation,and Ecological Jeremiad in Thomas Friedman's “Code Green”

Emerging popular literature trumpeting the prospects for Manifest Destiny through a greener capitalism illustrates the re-emergence of American myth to explain chaotic times and uphold America's exceptional character. Today, this character is dominated ideologically by the rhetorical repertoire of neoliberal economics. In this essay, the author dissects neoliberal rhetorical style as articulated through national myth and ecological jeremiad in bestselling author Thomas Friedman's (2008) “Code Green” thesis. In Code Green, an American strategy for confronting the convergence of global warming, new economic competition abroad, and population growth, the author traces a mythic “evolution” in ecological jeremiad toward a sustainable free market frontier. Crafting a muscular yet ostensibly non-political rhetoric of individualist sacrifice and reward, Friedman refigures the dark side of Western-led globalization's past.     

Carotenoid-dependent coloration of male American kestrels predicts ability to reduce parasitic infections

The signaling function of sexually selected traits, such as carotenoid-dependent avian plumage coloration, has received a great deal of recent attention especially with respect to parasitism and immunocompetence. We argue that parasite-mediated models of sexual selection may have an implicit temporal component that many researchers have ignored. For example, previous studies have demonstrated that carotenoid-dependent traits can signal past parasite exposure, current levels of parasitism, or the ability of individuals to manage parasitic infections in the future. We examined repeated measures of carotenoid-dependent skin color and blood parasitism in American kestrels (Falco sparverius) to distinguish whether coloration might signal current parasitism or the potential to deal with infections in the future. We found no evidence that coloration was related to current levels of parasitism in either sex. However, coloration of males significantly predicted their response to parasitism; males with bright orange coloration during prelaying, when mate choice is occurring, were more likely than dull yellow males to reduce their levels of infection by the time incubation began. Coloration during prelaying may advertise a male’s health later in the breeding season. For kestrels, the ability to predict future health would be highly beneficial given the male’s role in providing food to his mate and offspring. Coloration of females was not a significant predictor of parasitism in the future, and we provide several possible explanations for this result.     

Response of American redstarts (suborder Passeri) and least flycatchers (suborder Tyranni) to heterospecific playback: the role of song in aggressive interactions and interference competition

Least flycatchers (Empidonax minimus) and American redstarts (Setophaga ruticilla) overlap in the use of food resources on their breeding grounds, promoting high levels of interspecific aggression by the socially dominant flycatcher. We examined the role of song in this interspecific aggression by using repeated-measures-designed playback experiments and observational data on induced aggressive interactions. Flycatchers were more likely to approach the speaker during presentation of redstart song than during intervals of no song or presentation of control song. Approach was close enough to enable visual contact with a singing redstart. In contrast, redstarts made significantly fewer flights following presentation of flycatcher song, when risk of flycatcher attack may be greatest. Reducing the number of flights likely reduces the risk of flycatcher attack on the redstart, as flycatchers do not attack stationary redstart models and are apparently dependent on cues from redstart flight for visual heterospecific recognition. Flycatcher-specific responses of redstarts and marked differences in song morphology rule out misdirected intraspecific aggression as a proximate or ultimate cause of interspecific response to song. Results indicate that song is an important component in aggressive interactions between these two species, and reflect the dominant role of the flycatcher in such interactions. Our results also illustrate the capacity for interspecific interference competition to influence behavior and heterospecific song recognition in two distant avian taxa. Received: 10 January 1995/Accepted after revision: 8 June 1996     

Analysis of PFAAs in American alligators part 2: Potential dietary exposure of South Carolina hunters from recreationally harvested alligator meat

Exposure to perfluorinated alkyl acids (PFAAs) has been linked to many harmful health effects including reproductive disorders, developmental delays, and altered liver and kidney function. Most human exposure to environmental contaminants, including PFAAs, occurs through consumption of contaminated food or drinking water. This study uses PFAA data from meat samples collected from recreationally harvested American alligators (Alligator mississippiensis) in South Carolina to assess potential dietary exposure of hunters and their families to PFAAs. Consumption patterns were investigated using intercept surveys of 23 hunters at a wild game meat processor. An exposure scenario using the average consumption frequency, portion size, and median perfluorooctane sulfonic acid (PFOS) concentration in alligator meat from all hunt units found the daily dietary exposure to be 2.11 ng/kg body weight per day for an adult human. Dietary PFOS exposure scenarios based on location of harvest suggested the highest daily exposure occurs with alligator meat from the Middle Coastal hunt unit in South Carolina. Although no samples were found to exceed the recommended threshold for no consumption of PFOS found in Minnesota state guidelines, exposure to a mixture of PFAAs found in alligator meat and site-specific exposures based on harvest location should be considered in determining an appropriate guideline for vulnerable populations potentially exposed to PFAAs through consumption of wild alligator meat.     

Autotrophic Biological Denitrification for Complete Removal of Nitrogen from Septic System Wastewater

The overall objective of this research was to develop a reliable, robust, and maintenance-free passive system for biological denitrification in on-site wastewater treatment systems. The process relies on sulfur oxidizing denitrifying bacteria in upflow packed bioreactors. Since this process consumes alkalinity, it is necessary to add a solid-phase buffer that can scavenge the H⁺ as it is generated by the biologically-mediated reaction and arrest the drop in the pH value. This study investigated the use of limestone, marble chips and crushed oyster shell as solid-phase buffers that provide alkalinity. Two bench-scale upflow column reactors and two field-scale bioreactors were constructed and packed with sulfur pellets and an alkalinity source. The pilot scale bioreactors (∼200 L each) were installed at the Massachusetts Alternative Septic System Test Center (MASSTC) in Sandwich, MA. The pilot-scale bioreactors performed better when oyster shell was used as the solid-phase buffer vis-à-vis marble chips. In both (pilot-scale and laboratory-scale) systems, denitrification rates were high with the effluent NO₃ ⁻ —N concentration consistently below 8 mg/L.     

OVERCOMING THE NATION'S BEST LANDSCAPED SEWER: RECREATORS' PERCEPTIONS OF THE CONNECTICUT RIVER1

ABSTRACT: Once referred to as America's “best landscaped sewer,” the Connecticut has undergone a dramatic transformation in the last three decades. During this time, a number of public agencies and private organizations have worked diligently to implement policies and measures aimed at improving the river's quality. Ample data collected over the years indicate that the actual water quality conditions of the Connecticut River, as measured by empirical parameters, have improved. However, prior to this study, no data existed regarding the public's perceptions of these changes. This paper will address this issue by presenting the results of a multiyear survey designed to assess the public's perceptions regarding the Connecticut's current quality, and its suitability in supporting various recreational activities. The results suggest that the majority of individuals perceive the Connecticut's water quality to be high enough to support a wide range of recreational activities including those involving physical contact with the water. Additionally, this research concludes that the vast majority of individuals who have recreated on the river for 20 years or more do perceive a significant improvement in the river's overall quality. Thus, it appears that policies and actions taken to improve the Connecticut's quality have been successful in the public's eye.