火源位置对房间-走廊式结构下烟气危害性影响的实验研究

利用小尺寸典型建筑结构实验台选取了两种不同大小的油盘和三个典型的火源位置进行实验,同步获取浓度、温度、质量数据,对准稳态时段内的数据进行分析;以整个火源房间为控制体,以有害组分CO的积分平均浓度及生成率为研究对象,研究了不同火源位置影响下开口的气体质量流率与中性面高度之间的关系,以及火源热释放速率或中性面的高度对CO的浓度及生成率的影响.结果表明,无论火源处于近门角落还是远角,CO积分平均浓度及生成率的数据表明其烟气层的危险性均明显高于火源处于中心时的值.     

北京西山森林潜在火行为及防火林带有效宽度分布研究

可燃物类型及其栽量分布是决定林火行为的重要因素.以北京西山试验林场魏家村分场为研究区域,根据样地调查和森林清查数据对可燃物类型进行分类,并对可燃物载量的空间分布进行研究.根据历史气象数据确定当地平均最大风速平均值为3.6m/s,平均最大风速的最大值为14m/s,在此情景下,结合DEM数据和可燃物数据对研究区域的林火强度进行计算,并对防火林带的有效参数进行确定.     

不同流量水喷淋作用下典型软垫家具火灾特性全尺寸实验研究

文章以典型软垫家具--单人软垫沙发为研究时象,对全尺寸多功能热释放速率标准燃烧室ISO9705(3.6m×2.4 m×2.4 m)加装水灭火系统,采用ZSTP15型水喷淋喷头对单人沙发燃烧行为进行全尺寸实验研究.测量并分析总结了在0 L/min、35.8 L/min、50.6 L/min、62.0 L/min四种不同流量水喷淋作用下沙发燃烧的热释放速率、顶棚烟气温度和CO、CO2生成速率等火灾特性参数随时间变化的规律,结果表明,由于水的冷却和隔氧作用,水喷淋的施加对室内沙发燃烧性能有显著影响,且随着流量的改变其燃烧过程呈现不同的变化趋势.     

Determinants of Trust for Public Lands: Fire and Fuels Management on the Bitterroot National Forest

Management of public lands occurs today with high levels of scrutiny and controversy. To succeed, managers seek the support, involvement, and endorsement of the public. This study examines trust as an indicator of managerial success and attempts to identify and measure the components that most influence it. A review of trust literature yielded 14 attributes that were hypothesized to contribute to trust, grouped into the three dimensions of Shared Norms and Values, Willingness to Endorse, and Perceived Efficacy. Operationalizing these attributes and dimensions, a telephone survey was administered to a sample of Montana, USA, residents living adjacent to the Bitterroot National Forest (n = 1,152). Each of the attributes was measured in the context of federal lands fire and fuel management. Structural equation modeling showed that all 14 attributes were found to be influential contributors to levels of trust. Results suggest that if managers are to maintain or increase levels of public trust, they need to consider each of trust’s attributes as they make social, ecological, and economic resource decisions.     

Traditional olive orchards on sloping land: Sustainability or abandonment?

Traditional olive orchards account for a large share of the area under olives in the EU, particularly in marginal areas, like those analysed in the OLIVERO project. In general, traditional olive growing can be described as a low-intensity production system, associated with old (sometimes very old) trees, grown at a low density, giving small yields and receiving low inputs of labour and materials. Though such systems are environmentally sustainable, their economic viability has become an issue, since EU policies favour more intensive and competitive systems. Orchards that have not been intensified seem to be threatened by the recent reform of the EU olive and olive oil policy, as income support has been decoupled from production. The main purpose of this paper is to identify the present constraints to traditional olive growing, and to recommend some private and public interventions to prevent its abandonment. During the OLIVERO project, traditional olive production systems were identified and described in five target areas (Trás-os-Montes-Portugal, Cordoba and Granada/Jaen-Spain, Basilicata/Salerno-Italy, and West Crete-Greece). The causes and consequences of abandonment are discussed, based on the analysis of the costs and returns, which revealed that these systems are barely economically sustainable. Their viability is only assured if reduced opportunity costs for family labour are accepted, and the olive growing is part-time. Based on these results, recommendations are made to prevent the abandonment of traditional olive growing and to preserve its environmental benefits.     

Growth responses of low-alpine dwarf-shrub heath species to nitrogen deposition and management

Nitrogen deposition is a continuing problem in European alpine regions. We hypothesised that, despite climatic limitations, low-alpine Calluna heathland would respond to nitrogen addition with increased shoot growth and flowering and that fire and grazing would modify responses. In a five-year study, 0-50kgNha(-1)y(-1) were added, combined with burning (+/-) and clipping (+/-). Calluna vulgaris responded with increased shoot extension, but effects on flowering were variable. Burning enhanced the positive effect of nitrogen addition and negative effects of clipping. Sub-dominant shrubs generally did not respond to nitrogen. C. vulgaris shoot extension was stimulated by nitrogen addition of 10kgNha(-1)y(-1) (above background) supporting suggestions that alpine heathlands are sensitive to low levels of nitrogen deposition. Increased C. vulgaris growth could negatively impact on important lichen components of this vegetation through increased shading and competition. Climatic factors constrain productivity in this community, but do not prevent rapid responses to nitrogen deposition by some species.     

灾害教育类场所解说现状研究

防灾安全类博物馆、科技馆、遗址地、纪念馆等是开展灾害教育的最佳场所,此类场所公众灾害教育的开展依靠解说功能的发挥。目前关于灾害解说研究尚处于空白,故需对这类场所的解说理论与实践进行系统研究。本研究试图通过灾害类解说现状调查研究,发现问题,总结相应策略,促进社会灾害教育的开展。     

土壤脲酶和脱氢酶对活性X-3B红污染暴露的耐受性及机理研究

采用微宇宙实验方法,研究了棕壤、褐土、红壤等3种我国典型土壤中脲酶和脱氢酶对染料活性X-3B红污染的耐受性及其机理.实验结果表明,3种土壤中的脲酶和脱氢酶活性在试验较低浓度的活性X-3B红污染的环境中均被促进,但被促进的程度有所差异,具体表现为棕壤脲酶活性被促进的效果最为明显,其次红壤,褐土最弱;较低浓度的活性X-3B红污染对褐土脱氢酶活性的促进作用最强,其次红壤,棕壤最弱.3种土壤的脲酶和脱氢酶活性被促进的效果随着时间的推移逐渐减弱.3种土壤的脲酶和脱氢酶活性对高浓度的活性X-3B红污染并没有显示受抑制的趋势.相反,二者基本维持在未受染料活性X-3B红污染的对照土壤的活性水平.因此可以初步认为,土壤脲酶和脱氢酶对染料活性X-3B红的污染暴露毒性有耐受作用.基于实验结果,还就2种酶对活性X-3B红污染暴露的耐受机理进行了分析与探讨.     

某城市地下车库联络通道的消防安全研究

城市地下车库联络通道作为一种新型的地下交通联络通道,可净化地面交通,提高土地利用率,解决城市交通拥堵问题。然而这种通道兼有地下车库和城市交通隧道的特点,结构复杂,一旦发生火灾,损失较大。其防火设计的难点在于如何定性并选择合适的规范条文,因此有必要系统研究其消防安全问题并提出有效解决方案。以某城市地下车库联络通道为例,研究该通道的火灾危险性,提出防火分隔、探测报警、排烟以及人员安全疏散等消防设计方案和管理对策,并通过数值模拟方法验证了该方案的有效性和可行性。