氡的现状调查—来源,水平,检测,危害及清除

简要介绍了天然放射性气体氡的来源、检测方法、环境标准、室内外的水平，与人体健康的关系、清除方法及防护对策等，引用文献３２篇。     

Characteristics of airborne bacteria and fungi in some Polish wastewater treatment plants

The aim of this study was to characterize both the viable airborne bacteria and fungi collected in different types of wastewater treatment plants in Poland. Bacterial and fungal aerosols in five different wastewater treatment plants in Poland were studied, including the pioneering antibiotic resistance testing of airborne bacteria. Concentration level was measured using the six-stage Andersen impactor. After incubation, bioaerosol particles captured on nutrient media on Petri dishes were quantitatively evaluated and qualitatively identified. It was found that the concentration levels of both airborne bacteria and fungi ranged from 10² to 10³ colony-forming units/m³, in all stages of the wastewater treatment plants. The patterns of size distributions of airborne bacteria and fungi were very similar, showing dominant peaks typically in the size range between 3.3 and 4.7 μm. The majority fraction of small bacterial and fungal particles (less than 4.7 μm) in the studied areas indicates that the bioaerosol is relatively fresh, and mostly of local origin. The Gram-positive cocci and nonsporing Gram-positive rods were the dominating forms in the studied wastewater treatment plants environment. The existing differences in the concentration levels between sampling sites enabled identification of the main bioaerosol sources. The highest concentration of bacterial aerosol appeared in sections, where activated sludge post-processing and mechanical purifying are conducted. The most frequently occurring species in the sampled bacterial aerosol were Gram-positive cocci and nonsporing Gram-positive rods. Multi-antibiotic resistance testing showed that among the isolated airborne bacteria, the most antibiotic-resistant features were present among Bacillus species (especially Bacillus mycoides).     

The ecological implications of a Yakutian mammoth's last meal

Part of a large male woolly mammoth (Mammuthus primigenius) was preserved in permafrost in northern Yakutia. It was radiocarbon dated to ca. 18,500 ¹⁴C yr BP (ca. 22,500 cal yr BP). Dung from the lower intestine was subjected to a multiproxy array of microscopic, chemical, and molecular techniques to reconstruct the diet, the season of death, and the paleoenvironment. Pollen and plant macro-remains showed that grasses and sedges were the main food, with considerable amounts of dwarf willow twigs and a variety of herbs and mosses. Analyses of 110-bp fragments of the plastid rbcL gene amplified from DNA and of organic compounds supplemented the microscopic identifications. Fruit-bodies of dung-inhabiting Ascomycete fungi which develop after at least one week of exposure to air were found inside the intestine. Therefore the mammoth had eaten dung. It was probably mammoth dung as no bile acids were detected among the fecal biomarkers analysed. The plant assemblage and the presence of the first spring vessels of terminal tree-rings of dwarf willows indicated that the animal died in early spring. The mammoth lived in extensive cold treeless grassland vegetation interspersed with wetter, more productive meadows. The study demonstrated the paleoecological potential of several biochemical analytical techniques.     

Gamma radiation levels in the villages of South Konkan,Maharashtra, India

Ambient gamma radiation study was carried out in South Konkan using thermo luminescent dosimeters (TLDs). A statistical analysis was carried out to understand the distribution of gamma radiation in the study area. The annual effective doses (AEDs) received by the local population from the selected villages were 0.31 and 0.09 mSv year^?1 for indoor and outdoor locations, respectively. For indoor conditions, the maximum dose rate occurred for winter season and the minimum occurred in monsoon season while for outdoor conditions the maximum dose rate occurred in spring season and minimum occurred in the monsoon season. The terrestrial radioactivity in the corresponding villages was measured by a HpGe detector. The radiation hazard indices like absorbed dose rate in air (D), radium equivalent activity (Ra_eq), external hazard index (H _ex) and internal hazard index (H _in), and AED were calculated using soil radioactivity data. The minimum absorbed dose rate in air (33.97 nGy h^?1) corresponds to the Dale village and the maximum (101.86 nGy h^?1) corresponds to the Mithgawane village. Radiation hazard indices as Ra_eq, H _ex, and H _in were found to be within the limit. The average AED from natural radionuclides was found to be lower than the worldwide value. The AEDs of this study were compared with previous studies carried out worldwide. A positive correlation was observed for the absorbed dose rate in air and the activity concentration of U-238, Th-232, and K-40. A positive correlation between activity concentrations of U-238, Th-232, and K-40 was also observed. The comparison between the AEDs calculated using absorbed dose measured by TLDs and the values calculated from soil’s gamma spectrometry showed some variation in the villages of South Konkan.     

广东省温泉宾馆室内氡来源分析

利用RAD7便携式测氡仪和NR-67A型连续测氡仪测量了广东省一些温泉宾馆室内外氡浓度。从无人入住的宾馆房间内氡浓度的变化来看，土壤氡的渗入是底层房间氡的主要来源。当在浴室内使用温泉水洗浴时，客房内平均氡浓度水平比没有用温泉水时高出10．9％～813％，浴室内氡浓度比没有用温泉水洗浴时高出13．8％～489％。宾馆室内使用温泉水有较高的氡转换系数。某些宾馆室内氡浓度超标。可能对宾馆工作人员造成潜在健康危害，应采取一些管理措施或技术手段降低其暴露水平。     

青海高原不同生态功能区气候突变时间的比较分析

根据地理位置和地貌特征将青海省划分为东部农业区、 环青海湖区、 三江源区和柴达木盆地4个生态功能区, 利用这4个生态功能区1961-2010年的月平均气温和降水量资料, 对年和四季的平均气温及总降水量进行了突变检测.结果表明: 4个生态功能区年平均气温和四季气温都呈显著的上升趋势, 其中冬季气温上升最明显, 其次为秋季, 春季和夏季相对较小.气温突变时间检测表明, 年平均气温为柴达木盆地的突变时间最早, 其次为东部农业区和环湖区, 三江源区突变时间最晚.不同生态功能区四季气温突变时间不尽相同.年降水量除柴达木盆地上升趋势明显外, 其余三个地区变化趋势都不明显; 四季降水量变化趋势除冬季降水量变化明显(除东部农业区)外, 其余三季变化趋势基本不明显.降水量突变信号较气温突变信号弱, 只有个别地区的个别季节降水量发生了突变.     

Simulation of global warming effect on outdoor thermal comfort conditions

In the coming decades, global warming and increase in temperature, in different regions of the world, may change indoor and outdoor thermal comfort conditions and human health. The aim of this research was to study the effects of global warming on thermal comfort conditions in indoor ambiences in Iran. To study the increase in temperature, model for assessment of greenhouse-gas induced climate change scenario generator compound model has been used together with four scenarios and to estimate thermal comfort conditions, adaptive model of the American Society of Heating, Refrigerating and Air-conditioning Engineers has been used. In this study, Iran was divided into 30 zones, outdoor conditions were obtained using meteorological data of 80 climatological stations and changes in neutral comfort conditions in 2025, 2050, 2075 and 2100 were predicted. In accordance with each scenario, findings from this study showed that temperature in the 30 zones will increase by 2100 to between 3.4 °C and 5.6 °C. In the coming decades and in the 30 studied zones, neutral comfort temperature will increase and be higher and more intense in the central and desert zones of Iran. The low increase in this temperature will be connected to the coastal areas of the Caspian and Oman Sea in southeast Iran. This increase in temperature will be followed by a change in thermal comfort and indoor energy consumption from 8.6 % to 13.1 % in air conditioning systems. As a result, passive methods as thermal inertia are proposed as a possible solution.     

Environmental inequalities in New Zealand: A national study of air pollution and environmental justice

Research has established that many socially deprived, low income and ethnic minority communities are exposed to disproportionately high levels of outdoor air pollution. Whilst there is a burgeoning literature documenting these environmental disparities, most previous studies have taken place in North America and few researchers have examined local scale variations across an entire country. Further, there has been little work systematically evaluating disparities in the local exposure to air pollution from different sources. In this New Zealand research we use mean annual estimates of outdoor particulate air pollution for different sources for neighbourhoods across urban New Zealand to evaluate whether air pollution varies between local areas of differing socioeconomic circumstances. We find that outdoor pollution levels are higher in socially deprived areas (using a neighbourhood measure of disadvantage) and neighbourhoods with a high proportion of low income households. However, although ethnicity was also related to mean total pollution, levels were elevated in areas where the proportion European was higher and other ethnic groups (including Māori) were lower. We also find that the disparities in pollution levels are specific to the pollution source. The results are discussed in the context of the policy framework in New Zealand, including the tensions fashioned by the Resource Management Act 1991, which have effectively ‘desocialised’ environmental concerns. We argue that the regulatory framework is fixated on ‘environmental bottom lines’ rather than social concerns that are integral to the environmental justice framework. Some priorities for future research into environmental justice in New Zealand are also considered.     

Contradictions at the confluence of commerce,consumption and conservation; or,an REI shopper camps in the forest,does anyone notice?

Leave No Trace (LNT) is a United States government educational program guiding outdoor recreationist behavior on public lands. The program consists of seven principles imploring outdoor enthusiasts to “enjoy the outdoors responsibly.” This essay employs a political ecology framework, comprised by critical consumption research and political economic analysis, to engage the LNT program across temporal and spatial scales. We illustrate, first, the impossibility of ’leaving no trace’ even when adhering to the program’s principles. Second, we describe how LNT minimizes local environmental impacts by displacing them to distant locations. Third, we illustrate how LNT obscures connections between the uses of outdoor products and their production and disposal impacts. Along with challenging notions of responsible recreation and ethical consumerism, a close examination of Leave No Trace reveals four mechanisms that produce and maintain program contradictions: the development of private-nonprofit alliances; the indirect enclosure of public conservation areas; the perpetuation of truncated notions of environmental citizenship; and the cultivation of ethical consumer subjects that shop at retail outlets like Recreation Equipment Incorporated (REI).     

微型生物在岩溶碳循环中的作用研究回顾与展望

全球气候变化问题使岩溶系统碳循环的研究倍受关注,有关微型生物及其碳酸酐酶在岩溶系统碳循环中的作用的认识也在不断深入。文章回顾了微型生物及其碳酸酐酶在碳酸盐岩风化以及碳酸盐岩沉积过程中的作用过程及作用机制,指出未来的研究需结合不同岩溶生态环境,量化微型生物及其碳酸酐酶对岩溶生态系统碳增汇的影响,为深入研究微型生物及其碳酸酐酶对岩溶碳汇的贡献、增加岩溶生态系统碳汇的能力、助力实现碳中和提供参考。      

Identification and characterization of size-segregated bioaerosols at Jawaharlal Nehru University, New Delhi

Ambient levels of viable bioaerosol were measured at four different sites on the campus of Jawaharlal Nehru University (JNU), New Delhi, India. Most of the viable bioaerosol was associated with the fungal fraction with the remainder due to bacteria. The highest concentrations of fungi were found at a health center (1,293 cfu/m³). The highest concentrations of both gram-positive (338.8 cfu/m²) and gram-negative (614 cfu/m²) bacteria were found at a garbage dump site. Gram-negative bacteria were found in larger numbers than gram-positive, possibly due to the higher ambient temperatures during their sampling. Most of the fungal bioaerosol identified is associated with immunotoxic diseases such as sick building syndrome and allergic diseases and was found in respirable fractions. Since the bacterial fractions were identified on the basis of morphology, i.e. only to the level of genus, their relationship to health effects could not be established. Although most of the sampling occurred indoors in naturally ventilated buildings, external temperature and humidity did not vary significantly during the study. Thus, it is more likely that the types of organisms and levels observed had more to do with the sources (decomposing garbage, spores carried from wooded areas, etc.) than the ambient or indoor environmental conditions.     

Fungal air contamination in distinct sites within a municipal landfill area

Municipal wastes collected in landfills are a significant source of air contamination and frequently characterize by elevated concentrations of different fungi. Posing a serious health threat to landfill workers and local residents, the fungal aerosol has to be monitored with respect to its quantity and quality. In this study, concentrations of airborne fungi, their particle size distribution, species composition and the presence of cytotoxic strains of Aspergillus fumigatus were assessed in different sites within the landfill area. The quantitative and qualitative changes in the fungal aerosol were determined with respect to a season and landfill activity level (i.e. exploitation or standstill periods). Within the landfill area, particular sites were grouped with regard to airborne fungi concentrations and similarities in species composition. The qualitative analysis indicated that 43 species were shared during both sampling times, and only nine species were characteristic for the standstill period. Among fungal isolates, 21 strains of A. fumigatus revealed cytotoxic activity expressed at different levels, depending on the fungal extract concentrations used in the MTT assay. The results suggested that exposure (especially in summer) to small airborne particles, containing distinct species, may occur not only in the active sector but also in close vicinity to the landfill. Hence, microbial monitoring of the landfill and surrounding area should be carried out taking into account both quantitative aspect supplemented by size distribution analysis and qualitative features, especially of those strains possessing cytotoxic activity.     

基床系数的室内外测试方法分析与研究

对目前规范中测试基床系数的方法进行了探讨和分析 ,指出其不合理性 ,在此基础上 ,展开对基床系数的室内测试方法的研究 ,最后给出两种较为简单实用的室内测试方法     

Experimental and numerical analyses of particulate matter concentrations in underground subway station

The purpose of this paper was to perform the experimental and numerical analyses of PM₁₀ and PM_2.5 concentrations in Imam Khomeini (IKH) underground subway station in Tehran. The aim was to provide fundamental data in order to fulfill workers and passengers respiratory health necessities. Experimental measurements was done at three different locations (entrance, middle and exit) inside the platform and also outdoor ambient of the station. The Dust-Trak was applied to measure continuous PM_2.5 and PM₁₀ concentrations at a logging interval of 30 s. The measurements were recorded during rush hours (8:00 am–12:00 pm) for one week per each season from June 2015–June 2016.Moreover, computational fluid dynamic (CFD) simulation was done for the platform of the above station and the necessary boundary conditions were provided through field measurements. Those basic parameters which were considered for numerical analysis of particulate matters concentrations included air velocity, air pressure and turbulence. Furthermore, the piston effect caused by train movement inside the station provided natural ventilation in the platform. The results showed that seasonal measured PM_2.5 and PM₁₀ indoor concentrations had a variety range from 40–98 µg/m³ to 33–102 µg/m³, respectively, and were much higher than national indoor air quality standard levels. Meanwhile, PM_2.5 and PM₁₀ concentrations in the IKH underground subway station were approximately 2.5–2.9 times higher than those in outdoor ambient, respectively. Numerical simulation indicated that the predicted concentrations were underestimated by a factor of 8% in comparison with the measured ones.     

航空放射性测量

介绍了核工业航测遥感中心在寻找铀矿工作中的航空放射性测量的设备、经验和技术方法,已获得375.8万km²的航空放射性测量数据,在寻找铀矿和辐射环境评价中都取得理想的成果,并对石家庄市、秦山核电站周围地区天然放射性水平航空检测结果与高压电离室测量结果进行了对比;笔者着重阐述并建议将该中心在40多年勘查铀矿获得的航空放射性测量数据及其设备开发用于环境本底辐射评价、寻找丢失的点源和核事故应急航空监测。     

Distinctive microbial structures and the pre-phanerozoic fossil record

The live and sedimentary components of the flat laminated microbial mat at Laguna Figueroa have been studied since the late sixties. This paper reports the observation and isolation of a variety of micro-organisms, both prokaryotes and eukaryotes. The microbes were taken from the flat laminated mats submerged under at least one meter of water due to the spring rains of 1979 and 1980. Both in situ and enrichment culture observations were made using light and electron microscopic techniques. New strains of the following microbes are reported here: Bacillus megaterium, Bacillus licheniformis, Arthrobacter simplex and Paratetramitus jugosus. Several pseudomonads were isolated, some of which form distinctive subsurface colonial structures. Regular distinctive colony morphologies and desiccation resistant cysts were often observed, several types of which grow to characteristically large sizes and resemble objects found in the pre-Phanerozoic fossil record.Some colonies of manganese oxidizing bacilli and other bacteria are reminiscent of microfossils of the 2 Ga-old Gunflint Iron formation such as Metallogenium, Eosphaera tyleri, Eoastrion and Huronispora. Some manganese oxidizing bacteria form colonial structures that might be mistaken for individual organisms in the tens to hundreds of microns size range. The diversity of microbial structures, including those with preservation potential, must be kept in mind when interpreting the microfossil record.     

The abundance and distribution of the toxic dinoflagellate,Gonyaulax tamarensis,in Long Island estuaries

The distribution and abundance of motile cells of the toxic dinoflagellateGonyaulax tamarensis Lebour were monitored in estuarine waters of Long Island, a region with no previous history of shellfish toxicity. The population distribution was patchy, with the species detected in 40% of 115 estuaries examined during the spring bloom season. More detailed studies in four estuaries indicated that the dinoflagellate was most abundant in the headwater regions, with concentrations falling to undetectable levels at the mouths.G. tamarensis cell concentrations did not exceed 10⁵ cells per 1 and often remained an order of magnitude lower. In several instances, population growth and accumulation ceased under seemingly favorable environmental and nutritional conditions.     

Regional levels of indoor radon in Virginia and Maryland

The levels of Rn-222 in homes located in Fairfax County, Virginia, and Montgomery County, Maryland, are currently being measured during four consecutive three-month seasonal intervals using alpha-track detectors. Significant variations occur between parts of northern Virginia and southern Maryland because the area is part of three very different geologic provinces. Results from the winter period in these three provinces show that the indoor radon levels were about twice as high as anticipated. Approximately 45 percent of the homes had winter indoor radon levels above 4 pCi/l, the EPA’s recommended action level, and in the spring period, more than 30 percent of the homes still had indoor levels above 4 pCi/l. Indoor radon variations due to seasonal control were about as significant as geological control. Worst-case combinations developed over some rock units in the winter, producing areas in which about 70 percent of the homes exceeded 4 pCi/l.     

基于栅格尺度的阿勒泰地区旅游气候舒适度评价

气候的舒适度是游客选择旅游目的地的重要影响因素之一,利用1960-2013年近54 a的研究区气象统计资料,结合地理信息系统(GIS)空间分析方法,并考虑气温垂直递减规律这一因素,分析了阿勒泰地区500 m×500 m分辨率栅格尺度的逐月温湿指数、风效指数、着衣指数及综合舒适指数,通过对4个指数所反映的舒适度和舒适期进行对比分析,发现综合舒适指数可从客观角度反映气候因素对人体感觉的综合影响,能达到较为精准的评估效果.研究表明:阿勒泰旅游气候舒适度变化受当地地形和季节变化的影响较大,旅游舒适度季节变化明显,适宜户外旅游的舒适期短暂.季节变化中,冬季不适宜开展户外旅游活动;春季阿尔泰山山区气候舒适度不舒适,山区以南和西南萨吾尔山以北舒适度较不舒适;夏季分布在额尔齐斯河以北的山麓和山间河谷地区,以及青河县中部和南部,富蕴县南部地区人体感觉舒适,占全区总面积的39.62%,其余大部分区域较舒适;秋季分布在哈巴河县、布尔津县、阿勒泰市南部及福海县中部和南部区域感觉较舒适,占全区总面积的36.79%.阿勒泰地区旅游舒适期为1~5个月,旅游资源的空间分布契合该地区旅游舒适期的区域空间分布,利于本地区进行旅游开发和旅游活动.     

Ambient indoor/outdoor gamma radiation dose rates in the city and at high altitudes of Muzaffarabad (Azad Kashmir)

Preliminary results of ambient indoor/outdoor gamma dose rates measured for Muzaffarabad city, the state capital of Azad Kashmir, are presented. Measurements of indoor/outdoor environmental exposures were carried out using a portable Ludlum Model 19 Micrometer. Effect of altitude on measured values of gamma dose rates has also been investigated. Besides measuring the gamma dose rates for indoor and open environment, measurements have also been taken within two coal mines. Effects of lithology on gamma dose rates have also been investigated. For outdoor measurements, minimum and maximum gamma dose rates were found as 533 ± 4.33 and 1,143 ± 2.96 μGy y^?1, while for indoor environment minimum and maximum gamma dose rate value were found as 533 ± 4.33 and 979 ± 3.2 μGy y^?1. Average values of indoor and outdoor gamma dose rates were found as 761 ± 3.62 and 710 ± 3.75 μGy y^?1. Gamma dose rates have also been calculated with altitude variations. Measured values of gamma dose rates show a weak positive correlation with altitude. For measurements made in coal mines, maximum gamma doses rate value was found as 3,490 ± 1.69 μGy y^?1, situated at a height of 1,098 m, located at Sangri Mera. Results obtained from the current study show that annual effective doses from gamma radiation exposure does not pose health threat to the population of district Muzaffarabad.