Analysis of the selected optical parameters of filters protecting against hazardous infrared radiation

The paper analyses the selected optical parameters of protective optic filters used for protection of the eyes against hazardous radiation within the visible (VIS) and near infrared (NIR) spectrum range. The indexes characterizing transmission and reflection of optic radiation incident on the filter are compared. As it follows from the completed analysis, the newly developed interference filters provide more effective blocking of infrared radiation in comparison with the currently used protective filters.     

Fire and explosion hazard analysis during surface transport of liquefied petroleum gas (LPG): A case study of LPG truck tanker accident in Kannur,Kerala, India

This paper presents an analysis and simulation of an accident involving a liquefied petroleum gas (LPG) truck tanker in Kannur, Kerala, India. During the accident, a truck tanker hit a divider and overturned. A crack in the bottom pipe caused leakage of LPG for about 20 min forming a large vapor cloud, which got ignited, creating a fireball and a boiling liquid expanding vapor explosion (BLEVE) situation in the LPG tank with subsequent fire and explosion. Many fatalities and injuries were reported along with burning of trees, houses, shops, vehicles, etc. In the present study, ALOHA (Area Locations of Hazardous Atmospheres) and PHAST (Process Hazard Analysis Software Tool) software have been used to model and simulate the accident scenario. Modeling and simulation results of the fireball, jet flame radiation and explosion overpressure agree well with the actual loss reported from the site. The effects of the fireball scenario were more significant in comparison to that of the jet fire scenario.     

A novel method for evaluation of fire prevention by using water curtain with large droplets

Based on the ability to attenuate thermal radiation of droplets, water curtain plays an important role in fire prevention in the oil and gas terminal, traffic tunnel and other outdoor spaces. Radiation transfer characteristics of large droplets are determined by the Mie theory, and the Two-flux model is used to simplify the radiative transfer equation. Combined with an empirical formula to calculate the droplet diameter, a novel method is given for calculating the transmissivity of water curtain. Based on the method, influences of both the pressure and the width of water curtain on the transmissivity are fit for exponential relationship. Compared with experimental data, an ideal agreement is found between calculation results and experimental data for both single pipe water curtain and double pipe water curtain, only in the case of triplex pipe water curtain the deviation between calculation and experiment is more than 25%. A better calculation result can be obtained under the condition of the optical thin media. The method is effective in the scope of that the transmitted radiation is stronger than the environmental radiation.     

两起突发辐射环境事件的模拟监测

近两年来四川省成都、绵阳两市相继发生两起辐射环境事件,为澄清事实,消除公众疑虑,四川省辐射环境管理监测中心站对两事件分别开展模拟监测。着重介绍两事件的模拟监测情况,并对事件的影响进行评估。最终消除了公众的疑虑,维护了社会稳定。     

Larval performance of the mustard leaf beetle (Phaedon cochleariae, Coleoptera, Chrysomelidae) on white mustard (Sinapis alba) and watercress (Nasturtium officinale) leaves in dependence of plant exposure to ultraviolet radiation

Short-term exposure to ambient or attenuated ultraviolet (UV) radiation resulted in shifts in plant metabolite concentrations of the Brassicaceae Sinapis alba and Nasturtium officinale. Leaf quality also varied between plant species and within species due to age. Larvae of the oligophagous leaf beetle Phaedon cochleariae were raised on these different host leaves, in order to investigate the effects of variable plant chemistry on this herbivore. The performance of P. cochleariae was influenced by chemical differences between and within plant species but it responded with high plasticity to plants stressed by ultraviolet radiation. Body mass increase and developmental times of larvae were exclusively affected by plant species and leaf-age. However, developmental differences were fully compensated in the pupal stage. We suggest that the plasticity of herbivores may depend on the degree of specialisation, and insect performance may not necessarily be altered by stress-induced host plants.     

苍山5.2级地震前电磁辐射异常

利用枣庄电磁信息台ＤＰＪ Ⅲ、ＵＬＦ Ⅲ及ＪＤ ０３型电磁辐射仪观测到的资料，分析了山东苍山５．２级地震前多数台站记录到的异常信息及其特征。     

Studies of the effects of temperatures and solar radiation on volatilization,mineralization and binding of 14c‐DDT in soil under laboratory conditions

Abstract

The effects of temperatures and solar radiation on the dissipation of ¹⁴C‐p,p'‐DDT from a loam soil was studied by quantifying volatilization, mineralization and binding. The major DDT loss occurred by volatilization, which was 1.8 times more at 45^oC than at ambient temperature (30°C). Mineralization of DDT slowly increased with time but it decreased slightly with increase in temperature. Binding of DDT to soil was found to be less at higher temperatures (35 and 45°C) as compared to ambient temperature. Degradation of DDT to DDE was faster at higher temperatures.

Exposure of non‐sterilized and sterilized soils treated with ¹⁴C‐DDT to sunlight in quartz and dark tubes for 6 weeks resulted in significant losses. Volatilization and mineralization in quartz tubes were more as compared to dark tubes. The volatilized organics from the quartz tubes contained larger amounts of p,p'‐DDE than the dark tubes. Further, higher rates of volatilization were found in non‐sterilized soils than in sterilized soils. The results suggest that faster dissipation of DDT from soil under local conditions relates predominantly to increased volatilization as influenced by high temperature and intense solar radiation.     

内蒙古草原光合有效辐射的计算方法

2002年夏季,对内蒙古草原太阳分光辐射以及气象因素进行了同步观测。依据一定的物理基础,在对实测资料进行分析的基础上,计算得到了内蒙古草原地区光合有效辐射某一时段累计值的经验公式。实际天气条件下,计算结果与观测值比较接近,该经验公式的适用性亦比较好。根据不同条件,可以选择不同的因子来计算光合有效辐射。当选择全部因子时,计算值与观测值的最大相对偏差为8 13%,平均相对偏差为2 45%。研究表明,大气中所有物质对光合有效辐射的吸收作用小于它们的散射作用。      

三相内循环流化床光催化反应器及其光辐射传递规律

提出并建立了三相内循环流化床光催化反应器 ,对其内部光辐射传递规律进行了研究 .结果表明 ,在气固相共同作用下(通气量>0.3m³/h) ,光强的径向分布服从指数衰减规律 ,与Rose公式中通过均匀悬浊介质时的光强分布规律一致 .光辐射能的数值受初始光强 .催化剂颗粒浓度和液层厚度的共同影响 .通气量只影响床层流化状态 ,对光强分布影响可以忽略 .对罗丹明B的光催化降解实验表明 ,三相内循环流化床的光催化效率高于传统的悬浆式反应床 ,本系统的最佳催化剂浓度为10～12g/L .     

172nm真空紫外辐射降解水相有机染料的机理研究

研究了氙准分子灯的172nm真空紫外辐射对水相有机染料枣红的分解机理.氙准分子灯为平面状结构,反应溶液作为灯的一端电极直接与灯表面接触.分别在枣红溶液中通入氧气和氮气以及加入KCl,以具体确定172nm辐射对枣红分子的降解是通过直接光分解还是自由基起作用.研究结果表明,在枣红的降解过程中,直接光分解起主要作用,光降解过程符合准一级动力学反应,光量子产率为6 8×10 - 3mol·eistein- 1 .在HO·、HO2 ·和O2 ·- 自由基作用下,枣红的降解在10min后偏离了准一级反应.枣红降解效率达到约80 %后,COD去除率开始增大.GC MS分析表明,在光分解和热氧化作用下,枣红分子在降解过程中形成了许多小分子碎片.