扑救森林火灾时的注意事项

总结分析了在林火扑救中指挥员应掌握了解的基本情况及扑火队员应注意的事项。     

中国亚热带地区2000-2014年林火排放颗粒物时空动态变化

林火是森林生态系统重要干扰因子并对大气环境和人类健康有显著影响.该研究基于2000-2014年中国亚热带地区卫星火点数据,结合林业统计年鉴,估算各区域林火燃烧生物量,运用排放因子法,估算15年间中国亚热带地区林火排放颗粒物总量.研究结果表明,亚热带地区林火存在季节性差异,福建、广东、广西、湖南和江西林火主要集中在春、秋两季;贵州和云南林火主要集中在春季;浙江林火集中在春、夏两季.亚热带地区森林可燃物总燃烧量为333.92 Mt,污染物PM_2.5、OC、EC和TC总量分别为：698.33、338.18、40.04和378.22 kt,此外,各污染物排放在时间和空间上不均衡,各污染物排放量多集中在云南南部和东南部,湖南、贵州和广东交汇处,广东东南部和福建中部等区域;PM_2.5、OC、EC和TC在浙江、云南、贵州、湖南和江西呈显著增长趋势.林火释放PM_2.5与工业粉尘的排放比变化趋势总体呈上升趋势,说明森林火灾导致的颗粒物排放对大气环境影响力呈逐年增长趋势.该文通过对中国亚热带地区林火释放污染物的时空变化研究,为深入揭示林火对区域环境的影响提供数据支持.     

A review of hazards associated with primary lithium and lithium-ion batteries

Primary lithium batteries contain hazardous materials such as lithium metal and flammable solvents, which can lead to exothermic activity and runaway reactions above a defined temperature. Lithium-ion batteries operating outside the safe envelope can also lead to formation of lithium metal and thermal runaway. Despite protection by battery safety mechanisms, fires originating from primary lithium and lithium-ion batteries are a relatively frequent occurrence.This paper reviews the hazards associated with primary lithium and lithium-ion cells, with an emphasis on the role played by chemistry at individual cell level. Safety mechanisms to prevent the occurrence and limit the consequences of incidents are reviewed, together with safety tests to monitor compliance with battery safety regulations and standards. Incident information from news accounts and open literature sources are reviewed to extract causal information.It is concluded that the potential severity of incidents during storage, transport and recycling of waste batteries can be significantly higher than in end-use applications. Safe storage, packaging and labelling practices, as well as communication among the parties involved, are essential to ensure safety across the battery lifecycle. It is recommended that a database of lithium battery incidents would be valuable to improve the evidence base for informing accident prevention measures.     

当代森林火灾防控对策研究

我国森林防火事业应走科学防火、人文防火相结合的道路。在历史森林火灾资料散落和缺失的背景下,依据解放后森林火灾资料,考查分析表明我国森林火灾的特点是森林火灾严重、森林火灾发生地方比较集中、森林火灾具有一定的季节性并且森林火灾具有5-6年和10年的准周期,防控失误原因是指导思想缺乏科学的方法与人文的关怀、宣传有死角,火源管理不严、执行规章制度不严、防火阻隔带建设不够完善和专业扑火队员少,业务素质差;设备落后。我国森林火灾防控应该转换思路,从过去以牺牲人的生命为代价转换到以人为本的路径上来,通过充分利用符合国情的各项防火对策,有效促进各个林区的林火管理,提高林火控制能力,减少森林火灾,保护森林资源、生态环境和林区人民生命财产安全,实现林区社会稳定和林业可持续发展。     

氯醇化法环氧丙烷生产中的循环经济探索

从传统的氯醇化法环氧丙烷生产工艺和存在的环保问题入手,结合国内外对环氧丙烷循环经济和清洁生产新技术的研究,对循环经济的新技术进行清洁性分析,提出该技术可以从源头削减污染物产量,提高物料的循环利用率、水的综合利用率,符合清洁生产原则。     

Performance of water mist system with base injection in extinguishing small container fires

The purpose of the present work is the experimental investigation on the extinguishment of diesel container fires by a water-mist system with base injection through multiple nozzles placed symmetrically at various positions around the rim of the container. Experimental parameters selected are the orifice diameter of the nozzle, the number of nozzles, position of nozzles (angle of orientation, radial and vertical distance of the nozzle from the edge of the container), and injection pressure. Nozzles used in the present work are pressure-swirl nozzles with Z-type swirl-insert with solid-cone spray. Desirable properties of the system such as the non-clogging operation of the nozzle and uniform mass flux density in the spray are tested for the nozzles. The optimized solution is provided considering water consumption and the physical stability of the fuel surface in the container. Displacement of oxygen is observed as a predominant extinction mechanism due to the effective application of spray in the base region of the fire. The present work provides the parametric study of the extinction establishing the feasibility of the water mist system with a base injection for extinguishing tank fires. This may serve as guidelines for the preliminary design of the system with the extension for larger tank fires.     

煤田火区温室气体通量测量方法研究进展

为提高煤田火区温室气体通量测量的准确性,科学制定温室气区减排措施,笔者对国内外煤田火区温室气体测量方法进行梳理,对比分析各种测量方法的原理、优缺点和适用范围等,提出测量方法存在的问题及以后的研究方向。研究表明:目前所用的测量方法存在测量精度低、连续性差、假设理想化等缺陷,检测设备的改进应朝着能适应当地地表高温环境并能实现连续监测的方向发展,测量方法应更注重和新技术的结合。     

Effects of tungsten oxide on the activity and thermal stability of a sulfate-derived titania supported platinum catalyst for propane oxidation

A Pt/WO₃/TiO₂ catalyst for propane oxidation was prepared by a stepwise wet impregnation method, and was aged at 800℃ for 5 hr. Compared to the sulfate-derived titania supported catalyst, the introduction of tungsten oxide as stable Bronsted acid sites led to the formation of more metallic platinum active sites at the Pt/WO₃ interface. The dissociation of surface intermediates for propane oxidation was promoted on the WO₃-modified catalyst. This, as well as the inhibition effects of tungsten oxide on the sintering of anatase and the phase transformation to rutile, resulting in a high activity and thermal stability for the Pt/WO₃/TiO₂ catalyst.     

双火源对隧道火灾临界风速影响的数值研究

为研究双火源隧道火灾所需临界风速的变化规律,利用火灾动力学软件FDS模拟了三种双火源隧道火灾,即两等火源功率的火灾、上风流火源功率较大火灾、上风流火源功率较小火灾。根据各火灾情景下所得临界风速u_(cr),分析两火源距离d、火源功率、上下风流位置关系对临界风速u_(cr)的影响规律。结果表明:随着两火源距离d的增加,所需临界风速u_(cr)逐渐减小,当两者达到临界距离d_x时,临界风速u_(cr)为稳定值,该值由两火源上下风流位置关系和总火源功率共同决定;同种双火源火灾随着总火源功率增大,所需的临界风速u_(cr)增大;随着两火源间距离d增大,各双火源火灾所需临界风速u_(cr)的减小幅度不同;两火源距离d为零时,所需临界风速u_(cr)略大于同火源功率的单火源火灾所需的临界风速。     

Correlations between forest fires in British Columbia, Canada, and sea surface temperature of the Pacific Ocean

Correlations and cross-correlations between forest fires in the province of British Columbia, Canada, and sea surface temperatures in the Pacific Ocean were evaluated. British Columbia has a long Pacific Ocean coastline; given that there may be teleconnections between the province's forest fires and climate variability over the ocean, significant correlations may exist between forest fires and the sea surface temperature of the Pacific Ocean. Fire occurrences and areas burned through lightning-caused and human-caused fires were analyzed against individual 1° × 1° grid cells of anomalies in the sea surface temperature to determine correlations for the period 1950-2006. Significant correlations (p < 0.05) for vast areas of the ocean were found between occurrences of lightning-caused fires and sea surface temperature anomalies for time lags of 1 and 2 years, whereas significant correlations between occurrences of human-caused fires and sea surface temperature anomalies occurred extensively for many time lags. To support the results of this approach, correlations between fire data and the Niño 3.4, Pacific Decadal Oscillation, and Arctic Oscillation indices were tested for the same period. Significant correlations were found between fire occurrences and these indices at certain time lags. Overall, fire occurrence appeared to be more extensively correlated with sea surface temperature anomalies than was area burned. These results support the hypothesis that teleconnections exist between fire activity in British Columbia and sea surface temperatures in the Pacific Ocean, and the correlations suggest that linear regression models or other regression techniques may be appropriate for predicting fire severity from the sea surface temperatures of one or more previous years.