Characterisation of prompt and delayed atmospheric radioactivity releases from underground nuclear tests at Nevada as a function of release time

A database with information on about 500 cases of atmospheric radioactivity releases from underground nuclear tests is analysed. The data are statistically evaluated and systematically aggregated in order to characterise prompt uncontrolled as well as delayed operational releases of radioactivity into the atmosphere. The focus is put on the latter. The reported data compare well with theoretically derived xenon activities for reasonable nuclear test scenarios. Conclusions are drawn on the main features of releases that can be expected from underground nuclear tests as a function of release time. These findings are relevant for developing and validating methods to be applied in global monitoring of atmospheric radioactivity with respect to indications of an underground nuclear explosion.     

关于浙江几个大城市SO2排放年总控制量的探讨

国家标准GB／T13201－91推荐基于单箱模型推导出来的A值法制定地方大气污染物排放总量标准,该文在放弃了控制区呈圆形的假设之后推导出可利用风向大气稳定度联合频率的更为详细的单箱模型,并用于计算杭州、宁波、温州、衢州的SO₂排放年总控制量,在温州和衢州得到不同于A值法的结果。      

区域环境风险评价与管理初探

阐述了开展区域环境风险评价与管理的重要性,探讨了开展区域环境风险评价与管理的几个主要问题：区域环境风险水平的表征方法;区域环境风险的识别方法;区域环境风险评价的模式方法;以及区域环境风险管理的基本原则。开展区域环境风险评价与管理的目的是降低区域环境风险水平,减少人为事故带来的环境灾害与经济损失。给区域环境生态和公众健康一个较安全的保证。     

城市大气环境质量评价模糊识别理论模型

本文提出一种新的大气环境质量评价理论模型——模糊识别模型。提出了大气质量评价的指标综合权重矩阵概念及其确定方法。      

大气气溶胶中重金属元素痕量分析及形态分析研究进展

重金属是大气气溶胶的重要组成部分,由于重金属的气候效应、环境效应和健康效应,其痕量分析和形态分析越来越受重视.综述了大气气溶胶的采集、重金属的总量分析及形态分析技术,指出了当前研究工作中存在的问题及今后的发展方向.     

莱芜大气污染源排放颗粒物中多环芳烃研究

为了解莱芜市大气污染源排放颗粒物中多环芳烃的浓度及影响因素,采集机动车尾气尘、扬尘、工业燃煤颗粒物、民用燃煤颗粒物等4种样品,分别测定多环芳烃的含量。结果表明,莱芜市大气环境颗粒物中多环芳烃主要来源于机动车尾气和民用燃煤,12种多环芳烃类值分别为(1 536. 48±0. 78)和(299. 83±0. 30)μg/g,机动车尾气尘与扬尘、民用燃煤、工业燃煤多环芳烃均存在显著性差异。不同组分中,苯并(ghi)苝的值最高,为(559. 96±7. 59)μg/g,其次为晕苯,为(445. 36±5. 94)μg/g,城市空气污染呈现煤烟和机动车尾气复合污染的特点。     

雾霾天气背景下大气环境监测质量的提升路径研究

本文主要针对雾霾天气背景下大气环境监测质量的提升路径展开深入研究,先阐述了大气环境监测质量的提升重要性,比如有利于提高环境污染的防治水平、有利于不断提高城市环境规划水平等,然后重点提出了几点可行的提升路径,主要包括制定大气环境监测质量保障体系、加强环境质量监测网络建设、加强大气环境监测采样管理、加强3S技术的应用、加强监测监察联动协调机制、扩大大气环境质量评价范围等,确保监测数据与完整性和准确性相符,确保大气环境监测质量的稳步提升,以创建节能减排、生态环保的节约型社会。     

大气降尘测定中蒸发方式的选择

为了加快大气降尘样品的蒸发速度和报出数据的及时,经过分析总结,得出蒸发样品的步骤为:先电热套蒸发再水浴蒸发最后用电热板蒸发,这样既可以节省时间,又可以节约能耗,避免样品在空气中放置时间过长,空气中的尘粒进入样品中,影响样品测定的结果。     

Evaluation of large-scale CO2 storage on fresh-water sections of aquifers: An example from the Texas Gulf Coast Basin

Large-scale injections of CO₂ into subsurface saline aquifers have been proposed to remediate climate change related to buildup of green house gases in the atmosphere. The pressure buildup caused by such injections may impact a volume of the basin significantly larger than the CO₂ plume itself. In areas with hydrological settings similar to the Gulf Coast Basin, the perturbation of the flow-field in deep parts of the basin could result in brines or brackish water being pushed up-dip into unconfined sections of the same formations or into the capture zone of fresh-water wells. The premise of the current study is that the details of multiple-phase flow processes necessary to model the near field evolution of the CO₂ plume are not necessary to describe the impact of the pressure anomaly on up-dip aquifers. This paper quantitatively explores conditions under which shallow groundwater would be impacted by up-dip displacement of brines, utilizing an existing carefully calibrated flow model. Modeling an injection of water, arguably equivalent to 50 million tons of CO₂/year for 50 years resulted in an average water-table rise of 1 m, with minor increase in stream baseflow and larger increase in ground water evapotranspiration, but no significant change in salinity.