轻柴油储罐火灾过程及安全性评价

从 2 0 0 2年 1月 1日起我国实施新的“轻柴油”产品标准 ,新标准将轻柴油的闪点指标由原来的≥ 65℃改为≥ 5 5℃ ,由此导致轻柴油的火灾危险类别发生变化 ,并进而引发原有轻柴油储罐能否安全储存新标准轻柴油的问题。笔者利用化学流体力学模型和挪威船级社 (DNV)的SAFETI风险评估软件对 65℃闪点和 5 5℃闪点轻柴油的储存火灾危害性进行了评估 ,取得了轻柴油火灾中危害程度的计算机模拟结果     

Colonization and Selection of Fly-Ash Substrates by Marine Invertebrates

Fly-ash dumped on the sea bed causes a local impoverishment of the benthos. Experiments on ash in sea water have shown bacterial colonization to occur, at a slower rate than on natural silt, limited meiofaunal colonization after 18 months, selection by meroplanktonic larvae for the ash, though inhibition of development after settlement, and selection against ash by mobile benthic adults. the major inhibition to colonization is the lack of organic content in the ash.     

Studies on enhanced degradable plastics. II. Weathering of enhanced photodegradable polyethylenes under marine and freshwater floating exposure

The weatherability of three types of enhanced photodegradable polyethylene films and corresponding control films were studied under outdoor and marine floating conditions at two exposure sites. Progress of weathering was monitored using tensile elongation at break. In general, both the enhanced-degradable plastics and the corresponding controls degraded slower in marine exposure than in outdoor exposure. This is attributed to the lower sample temperatures (compared to samples exposed outdoors) and to shielding from light afforded by surface fouling in samples exposed floating in sea water. Enhanced-photodegradable polyethylenes disintegrated faster than the control samples in the case of both outdoor and marine exposures. The improvement obtained in marine exposures was greater than that for outdoor exposure of corresponding sample types. This is due to the extremely slow rates of disintegration of control films under marine floating conditions.     

Exposure of Marine Mammals to Genotoxic Environmental Contaminants: Application of the 32P-Postlabeling Assay for Measuring DNA-Xenobiotic Adducts♯

There is little information on exposure of marine mammals to genotoxic environmental contaminants. The 32P-postlabeling assay has been successfully used to assess exposure to genotoxic polycyclic aromatic compounds in fish and humans. In the present study, a preliminary investigation showed that polycyclic aromatic compound-like DNA adducts were present in hepatic tissues of harbor seals (Phoca vitulina richardsi) exposed to petroleum following the Exxon Valdez oil spill. However, for marine mammals, effects from changes in tissue condition on DNA recovery and quality is of concern, because tissue samples are often collected from animals that have been dead for unknown periods of time. To assess the effects of postmortem thermal history on DNA recovery from tissue and on DNA adduct quantitation, samples of harbor porpoise (Phocoena phocoena) hepatic tissue were incubated for up to 10 d at 4 and 30 °C. Only traces (<4 g) of hepatic DNA were recovered from 200 mg of tissue after incubation at 30 °C for 36 h. At 4 °C, DNA (50–130 g) was recovered from tissue incubated for up to 6 d; whereas DNA recovery at 10 d was minimal. Chromatograms of 32P-labeled DNA digests of liver tissue held at 4 and 30 °C and salmon sperm DNA held at 30 °C for 2 d had comparable profiles, suggesting that alteration of DNA bases had occurred during incubation of porpoise liver tissue. Moreover, the chromatograms of DNA extracted from liver tissues of harbor porpoises caught incidentally in a northwest Atlantic fishery, packed in ice and sampled several days later also exhibited similar altered DNA structures. Although, altered DNA structures that can interfere with the DNA adduct quantitation were present in autolyzed tissue, changes in the 32P-postlabeling chromatography conditions can decrease the interference. Moreover, in a study with tissues taken from California sea lions (Zalophus californianus) immediately postmortem and stored at –80 °C until processing, DNA structures associated with tissue breakdown were not observed. The DNA from sea lions, however, had putative age-dependent hepatic DNA modifications, which have a distinctive profile, and must be considered when evaluating exposure of marine mammals to polycyclic aromatic compounds. Overall, the findings showed that with attention to the postmortem thermal history of the tissue samples hepatic DNA adducts, as measured by 32P-postlabeling, have the potential to serve as a biological indicator of exposure of marine mammals to environmental genotoxic compounds.     

海洋信息工程安全生产管理体系建设研究

海洋信息工程是战略性与风险性并存的新兴产业,如何科学构建安全生产管理体系、有效管控安全风险,成为各界关注的重点。本文分析了海洋信息工程的高风险性,围绕风险管控探索海洋信息工程安全生产管理体系建设的原则和策略,创新地提出"三全"法、一库四系统、多元共治等风险辨识治理措施,为海洋信息工程安全生产管理体系建设提供多种方法。     

FDA事故致因模型在海上船舶碰撞事故安全管理中的运用研究

FDA事故致因模型从安全信息视角出发,将海上船舶碰撞事故发生的宏观与微观因素系统地结合在一起,以管理科学和技术科学为依据,构建海上船舶碰撞FDA事故致因模型,从微观到宏观即个体船只、海运企业、海事局3个层面进行安全信息视域下的事故致因分析,通过逻辑推导定位最佳的安全管理方位。研究结果表明:FDA事故致因模型由3条事故子链及1条事故主链构成,能够从微观到宏观完整表达海上船舶碰撞事故发生过程及机理;破坏3条FDA事故子链或FDA事故主链的形成即可有效地预防海上船舶碰撞事故的发生,对促进海上船舶航行安全管理水平的提高具有重要的理论与现实意义。     

PODE掺混比对电控共轨柴油机排放特性的影响

为了降低柴油机排放、提高热效率,将体积分数为10%、20%、30%和70%的聚甲氧基二甲醚(PODE)掺混于柴油中制得PODE/柴油混合燃料,标记为P10、P20、P30和P70,在一台四缸增压中冷电控共轨柴油机上开展了PODE掺混比对混合燃料燃油经济性与排放特性的试验,并采用热重分析仪研究了混合燃料的蒸发性能。结果表明:随PODE掺混比增加混合燃料的初始失重温度、终止失重温度和峰值失重温度均向低温区域偏移,峰值失重率增大;随PODE掺混比增加,柴油机的排气温度降低,有效热效率显著提升,混合燃料的HC、CO和烟度排放逐渐降低,而NOx排放有所增加;在ESC试验循环下P30的HC、CO和PM排放量较柴油分别降低了25%、16%和51%,均低于国V排放限值,且CO2排放量也明显减小。     

大功率应急柴油发电机组主油罐配置优化研究

为有效降低某工程大功率应急柴油发电机组主油罐的火灾安全风险和设备制造地下就位安装难度,通过对相关规范的分析,研究了两种主油罐配置优化方案,从规范符合性、油罐制造、油罐安装、安全性、运行要求和投资方面进行了比较,确定采用主油罐分置方案,并应用到具体工程项目。     

Electrochemical NOx reduction and oxidation of HC and PM emissions from biodiesel fuelled diesel engines using electrochemically activated cell

NOx emission is produced during combustion of fuels at high temperature. Excessive release of NOx causes several effects on living organisms and environment. In this work, the efforts to reduce NOx emission by developing electrochemically activated cells (EACs) for a diesel engine fuelled with diesel and biodiesel fuel are discussed. EAC technique is vital after treatment technology attempted in this work to simultaneous control of NOx, HC, and PM emissions. In this method, two types of EACs were developed. The CuO–YSZ electrolyte and CuO–YSZ electrolyte with BaO coating were developed and tested with diesel and biodiesel exhaust. Compared with diesel fuel, use of biodiesel fuel increased NOx emission by 11% and PM emission was slightly reduced with biodiesel, which was due to the presence of fuel bond oxygen content in biodiesel. The investigation has demonstrated low-temperature activation of the EACs at 250–350°C which was due to the addition of CuO to YSZ. In this work, maximum NOx reduction was achieved for CuO–YSZ cells with BaO NOx storage and the simultaneous control of HC and PM emission also was observed in this technique. NOx reduction by EAC is a vital technique and can be retrofitted with any diesel engine for emission reduction.