核电站浸渍活性炭阴燃蔓延特性的实验研究

碘吸附器内的核级浸渍活性炭是核电站主要火灾荷载之一,首先通过热重实验与分析,确定了核级浸渍活性炭阴燃前锋温度为350℃,获得了活化能为48.6 kJ/mol。继而基于自主设计的圆柱型活性炭填充床阴燃模拟实验台,在无强迫气流条件下,针对上表面中心引燃条件下的核级浸渍活性炭横向与纵向阴燃蔓延特性进行了实验研究。填充床径向截面温度场重构结果表明,核级浸渍活性炭在高温点热源作用下,易形成快速发展的阴燃蔓延燃烧过程。其中,横向蔓延燃烧速度达3.6 mm/min,明显快于纵向蔓延速度的0.5 mm/min。此外,内部温度场动态演化过程表明,浸渍活性炭向下蔓延燃烧过程中,将在其中部区域形成不断扩大的高温燃烧区,局部温度高于700℃,而此时其上表面温度却相对降低,易掩盖内部的危险区域。     

Heidegger and Being at the Hanford Reservation: Standing Reserve,Enframing, and Environmental Communication Theory

This essay examines the potential of Heidegger's phenomenology as a foundation for environmental communication theory, emphasizing his critiques of modern science, technology, humanism, and metaphysics. A phenomenological approach to environmental communication provides resources for recognizing metaphysical assumptions that endanger both humans and nature. The Hanford nuclear reservation serves as an illustrative text, exemplifying Heidegger's reading of nuclear energy as a culmination of both Western metaphysics and the instrumental stance that he calls “enframing.” In Heidegger's view, the ordering and control accomplished through enframing obscures the mutually constitutive relationship between humans and nature, and in doing so, diminishes the possibilities for authentic human existence. The chapter examines how both representational and constitutive models of communication contribute to those conditions, and adopts a set of concepts from Heidegger's phenomenology as a foundation for an alternative, “bounded constitutive” model.     

Arguments For What No One Wants: The Narratives of Waste Storage Proponents

In this essay, the authors examine the public discourse of three different proponent groups (Native Americans, Industry, and Community Advocates) to gain insight into the narratives used to justify the decision to support a typically unwanted land use. The questions they ask are: first, who are the actors, what is their agency, and what is their purpose, as revealed through an analysis of the compiled text? Second, in what ways do their stories combine into a coherent narrative of support for the project; and, finally, does the meta-narrative resonate with their primarily western states audience? They conclude with suggestions as to how this project informs participants in other waste management controversies.     

Predicting the effects of ionising radiation on ecosystems by a generic model based on the Lotka–Volterra equations

The present work describes a model for predicting the population dynamics of the main components (resources and consumers) of terrestrial ecosystems exposed to ionising radiation. The ecosystem is modelled by the Lotka–Volterra equations with consumer competition. Linear dose–response relationships without threshold are assumed to relate the values of the model parameters to the dose rates. The model accounts for the migration of consumers from areas characterised by different levels of radionuclide contamination. The criteria to select the model parameter values are motivated by accounting for the results of the empirical studies of past decades. Examples of predictions for long-term chronic exposure are reported and discussed.     

CO2 dispersion around two PWR nuclear power plants in Brazil

Atmospheric air samples were taken within 3 km from power plants encompassing five different distances and wind directions. Samples were taken between 2002 and 2005 aiming to evaluate the environmental ¹⁴C enrichment due to the operation of Brazilian nuclear power plants. The sampling system consisted of a pump connected to a trapping column filled with a 3 M NaOH solution. The trapped CO₂ was analyzed for ¹⁴C by using a single stage accelerator mass spectrometry (SSAMS).     

A rapid isotope ratio analysis protocol for nuclear solid materials using nano-second laser-ablation time-of-flight ICP-MS

The analysis of the isotopic composition of nuclear or non-nuclear solid materials is performed in a variety of fields, e.g., for quality assurance in the production of nuclear fuels, as signatures in forensics, nuclear safeguards, and non-proliferation control, in material characterization, geology, and archeology. We have investigated the capability of laser ablation (New Wave Research, 213 nm) coupled to time-of-flight (TOF) ICP-MS (GBC OptiMass 8000) as a rapid analytical protocol for multi-isotope screening of nuclear and non-nuclear solid samples. This includes natural and non-natural isotopic compositions for elements including Cu, Zr, Mo, Cd, In, Ba, Ta, W, Re, Pt, Pb, and U, in pure metals, alloys, and glasses. Without correcting for mass bias (mass fractionation), an overall precision and accuracy of about 4% (1σ) can be achieved by minimizing the deposited laser power and thus fractionation (mass removal based on thermal properties). The precision and accuracy in combination with literally no or minimized sample preparation enables a rapid isotope screening of solid samples that is of particular interest to support nuclear forensic and safeguard analysis.     

Modeling Long-Term Risk to Environmental and Human Systems at the Hanford Nuclear Reservation: Scope and Findings from the Initial Model

The Groundwater Protection Project at the US Department of Energy Hanford Site in Washington State is currently developing the means to assess the cumulative impact to human and ecological health and the regional economy and cultures from radioactive and chemical waste that will remain at the Hanford Site after the site closes. This integrated system is known as the System Assessment Capability (SAC). The SAC Risk/Impact Module discussed in the article uses media- and time-specific concentrations of contaminants estimated by the transport models of the integrated system to project potential impacts on the ecology of the Columbia River corridor, the health of persons who might live in or use the corridor or the upland Hanford environment, the local economy, and cultural resources. Preliminary Monte Carlo realizations from the SAC modeling system demonstrate the feasibility of large-scale uncertainty analysis of the complex relationships in the environmental transport of contaminants on the one hand and ecological, human, cultural, and economic risk on the other. Initial impact results show very small long-term risks for the 10 radionuclides and chemicals evaluated. The analysis also helps determine science priorities to reduce uncertainty and suggests what actions matter to reduce risks.     

Health cost of a nuclear waste repository,WIPP

The Waste Isolation Pilot Plant (WIPP), the United States of America's first nuclear waste dumping site, has over the years generated a great deal of concern and controversy. The most sensitive aspect of this project is that it may impose serious health risks on future generations. The first leg of this project is about to be completed and at the time of writing the Department of Energy is planning to perform experiments with a small quantity of waste for operational demonstrations. If everything goes well, then towards the end of this decade large quantities of wastes will be transported to the site for disposal. This article reconsiders the health cost of this project from an economic perspective in light of recent developments in the field of social discounting. As in earlier studies, two cases of health risks are considered: total cancer and genetic deformity over a one million year cutoff period. The analysis shows that whereas ordinary discounting method wipes out the future health detriments, expressed in monetary terms, the modified discounting criterion retains a substantial proportion of such costs in economic analysis.     

英国的核废物监测

本文介绍了英国核废物管理和监测的有关情况，并对放谢性“三废”的监测方法进行了阐述。     

Tourism impacts of Three Mile Island and other adverse events: Implications for Lincoln County and other rural counties bisected by radioactive wastes intended for Yucca Mountain

Whether the proposed Yucca Mountain nuclear waste repository system will adversely impact tourism in southern Nevada is an open question of particular importance to visitor-oriented rural counties bisected by planned waste transportatin corridors (highway or rail). As part of one such county's repository impact assessment program, tourism implications of Three Mile Island (TMI) and other major hazard events have beem revisited to inform ongoing county-wide socioeconomic assessments and contingency planning efforts. This paper summarizes key research implications of such research as applied to Lincoln County, Nevada. Implications for other rural counties are discussed in light of the research findings.