A Study on Applying Phenol Foam Insulation Material as Pipe Lagging Material

During a fire, the major cause of casualties is the toxic gas produced from combustible interior and exterior materials. Increasing the time for occupant evacuation by reducing toxic gas is the most effective way of reducing casualties. Many casualties occurred in recent fires at the Jecheon Sports Center, Miryang Sejong Hospital, and Icheon Distribution Center. The commonality is that the toxic gas produced from combustible interior and exterior materials was the major cause of the casualties. In this study, phenol foam insulation material was considered as an alternative pipe lagging material, owing to its limited combustibility and non-production of toxic gas, to determine a method for removing the toxic gas generated from the combustion of pipe lagging material. Phenol foam insulation material is often used as the insulation material for building exteriors owing to its excellent insulation performance. Moreover, it has the advantage of being an environment-friendly product with zero ozone layer destruction coefficient and low harmful substance emissions. The incombustibility of phenol foam insulation material was verified through the Standard Performance Test of the Limited Combustible Material (Ministry of Land, Infrastructure and Transport Notice No. 2020-1053). Further, an alternative is to be proposed if a pipe lagging material with inadequate incombustibility is used in the site even though a tested pipe lagging material with limited combustibility is available.

Antarctic ozone depletion measured by balloonsondes at Maitri - 1992

ABSTRACT. Profiles from a series of balloon borne ozonesonde ascents are used to chart the development of the Antarctic depletion over Maitri in the austral spring of 1992. The vertical structure of the ozone layer is discussed, including the presence of stratification, which occurs at all stages of development. The main feature of 1992 ozonesonde flights is depletion of 97% in the months of September and October between 15-23 km, which is unique.

Potential environmental impact of bromoform from Asparagopsis farming in Australia

To mitigate the rumen enteric methane (CH4) produced by ruminant livestock, Asparagopsis taxiformis is proposed as an additive to ruminant feed. During the cultivation of Asparagopsis taxiformis in the sea or in terrestrial based systems, this macroalgae, like most seaweeds and phytoplankton, produces a large amount of bromoform (CHBr3), which may contribute to ozone depletion once released into the atmosphere. In this study, the impact of CHBr3 on the stratospheric ozone layer resulting from potential emissions from proposed Asparagopsis cultivation in Australia is assessed by weighting the emissions of CHBr3 with the ozone depletion potential (ODP), which is traditionally defined for long-lived halogens but has been also applied to very short lived substances (VSLSs). An annual yield of ~3.5 × 104 Mg dry weight (DW) is required to meet the needs of 50 % of the beef feedlot and dairy cattle in Australia. Our study shows that the intensity and impact of CHBr3 emissions varies dependent on location and cultivation scenarios. Of the proposed locations, tropical farms near the Darwin region are associated with largest CHBr3 ODP values. However, farming of Asparagopsis using either ocean or terrestrial cultivation systems at any of the proposed locations does not have potential to impact the ozone layer. Even if all Asparagopsis farming was performed in Darwin, the emitted CHBr3 would amount to less than 0.016 % of the global ODP-weighted emissions. The remains are relatively small even if the intended annual yield in Darwin is scaled by a factor 30 to meet the global requirements, which will increase the global ODP-weighted emissions by 0.48 %

Dynamics of the Great Oxidation Event from a 3D photochemical-climate model

From the Archean toward the Proterozoic, the Earth's atmosphere underwent a major shift from anoxic to oxic conditions, around 2.4 to 2.1 Gyr, known as the Great Oxidation Event (GOE). This rapid transition may be related to an atmospheric instability caused by the formation of the ozone layer. Previous works were all based on 1D photochemical models. Here, we revisit the GOE with a 3D photochemical-climate model to investigate the possible impact of the atmospheric circulation and the coupling between the climate and the dynamics of the oxidation. We show that the diurnal, seasonal and transport variations do not bring significant changes compared to 1D models. Nevertheless, we highlight a temperature dependence for atmospheric photochemical losses. A cooling during the late Archean could then have favored the triggering of the oxygenation. In addition, we show that the Huronian glaciations, which took place during the GOE, could have introduced a fluctuation in the evolution of the oxygen level. Finally, we show that the oxygen overshoot which is expected to have occurred just after the GOE, was likely accompanied by a methane overshoot. Such high methane concentrations could have had climatic consequences and could have played a role in the dynamics of the Huronian glaciations.

Diesel engine hazard particles emission and measures to eliminate them

European union's goal is to eliminate hazard emission up to 2050. Main field of acting towards this goal is road traffic. Diesel engines has important influence at personal and transport vehicles. Most of heavy trucks and buses are propelled with diesel engines beacause of their reliability, fuel efficiency and tourqe. These engines are simple to maintain, cheap to produce and extremly durable. Main propblem with diesel engines are solid hazard particles emission and nitrosoxide. Health expets are concluded that these hazards effects human health, as well damaging ozone layer in athmosphere and create acid rains.

Kindergarten Teacher Students’ Knowledge Regarding Crucial Environmental Challenges

Global warming and a decline in pollinating insects are among the most crucial challenges today and a sufficient degree of scientific literacy is required for citizens in order to understand these issues and take action for sustainable development in general. Several studies have investigated knowledge associated with the greenhouse effect and the effect of the ozone layer. These have deduced that despite improvement in teaching tools, a high proportion of pupils and students still confuse these two phenomena. Previous research has also shown that plant biology is a neglected subject and students struggle to differentiate between pollination and seed dispersal. This study investigates the understanding regarding the mechanisms underlying global climate change and pollination by conducting a survey with four classes of Norwegian kindergarten teacher students, at the beginning of the academic year (n = 103), and by asking follow-up questions after completed teaching (n = 111). It was observed that approximately 40 percent of the students confused the greenhouse effect with the effect of the hole in the ozone layer. One fifth of the students mentioned photosynthesis while describing the importance of the Sun for life on Earth. About one third of them connected pollen to plant reproduction and two thirds believed that pollen is seeds. A survey at the end of the academic year showed that a substantial proportion of the students displayed teaching resilience. These results can be interpreted in the light of constructivist learning theory and might partly be explained by the role mass media play in influencing scientific literacy. For future citizens to make informed decisions, ecological issues should be prioritised in education.