• Fire Science and Engineering
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• v.22 no.2
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• pp.104-107
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• 2008

Heat release rates of main combustibles in residence area were measured by a calorimeter using oxygen consumption method. It was found that the peak heat release rates of the combustibles were 1.0MW for a refrigerator, 0.8MW for a desk, 4.2MW for a wardrobe and 0.4MW for a bed. Especially, the refrigerator and wardrobe were found to be very hazardous because of their fast fire growth rate.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.10
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• pp.4047-4054
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• 2010

We studied the release characteristics of the marine sediment which could facilitate sea eutrophication through some lab-scale simulation experiments. Environmental indicators such as pH, ORP(oxidation reduction potential), nitrogens, and phosphates were measured in order to calculate the corresponding release rates. $CaO_2$, an oxygen releasing compound was used to determine how it would effect on the natural process of sedimental release. COD, ammonia nitrogen, phosphorous compounds were less released under the oxic environment caused by $CaO_2$. This basic data will help developing methodology for reducing marine eutrophication which may be initiated by the sedimental release.

• Archives of Pharmacal Research
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• v.25 no.5
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• pp.675-680
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• 2002

In order to investigate the underlying mechanism of HCI in oesophagitis, the inflammatory response to HCI was observed in RBL-2H3 mast cells. Rat basophilic leukemia (RBL-2H3) cells were used to measure histamine release, arachidonic acid (AA) release, reactive oxygen species (ROS) and peroxynitrite generation induced by HCI. Exogenous HCl increased the level of histamine release and ROS generation in a dose dependent manner, whereas it decreased the spontaneous release of [$^3$H] M and the spontaneous production of peroxynitrite. Mepacrine (10 $\mu$M), oleyloxyethyl phosphorylcholine (10 $\mu$M) and bromoenol lactone (10 $\mu$M) did not affect both the level of histamine release and ROS generation induced by HCI. U73122 (1 $\mu$M), a specific phospholipase C (PLC) inhibitor did not have any influence on level of histamine release and ROS generation. Propranolol (200 $\mu$M), a phospholipase D (PLD) inhibitor, and neomycin (1 mM), a nonspecific PLC and PLD inhibitor, significantly inhibited both histamine release and ROS generation. Diphenyleneiodonium (10 $\mu$M), a NADPH oxidase inhibitor, and tiron (5 mM), an intracellular ROS scavenger significantly inhibited the HCI-induced histamine release and ROS generation. These findings suggest that the inflammatory responses to HCI is related to histamine release and ROS generation, and that the ROS generation by HCI may be involved in histamine release via the PLD pathway in RBL-2H3 cells.

• Journal of Environmental Science International
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• v.28 no.10
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• pp.851-861
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• 2019

In this study, we performed a sediment elution experiment to evaluate water quality in terms of phosphorus, as influenced by the dissolved oxygen consumed by sediments. Three separate model column treatments, namely, raw, calcined, and sonicated oyster shell powders, were used in this experiment. Essential phosphorus fractions were examined to verify their roles in nutrient release from sediment based on correlation analyses. When treated with calcined or sonicated oyster shell powder, the sediment-water interface became "less anaerobic," thereby producing conditions conducive to partial oxidation and activities of aerobic bacteria. Sediment Oxygen Demand (SOD) was found to be closely correlated with the growth of algae, which confirmed an intermittent input of organic biomass at the sediment surface. SOD was positively correlated with exchangeable and loosely adsorbed phosphorus and organic phosphorus, owing to the accumulation of unbound algal biomass-derived phosphates in sediment, whereas it was negatively correlated with ferric iron-bound phosphorus or calcium fluorapatite-bound phosphorus, which were present in the form of "insoluble" complexes, thereby facilitating the free migration of sulfate-reducing bacteria or limiting the release from complexes, depending on applied local conditions. PCR-denaturing gradient gel electrophoresis revealed that iron-reducing bacteria were the dominant species in control and non-calcined oyster shell columns, whereas certain sulfur-oxidizing bacteria were identified in the column treated with calcined oyster powder.

• The Korean Journal of Physiology and Pharmacology
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• v.1 no.6
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• pp.657-664
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• 1997

The effects of adenosine, adenosine A1 receptor antagonist (DPCPX), or NMDA receptor antagonist (APV) on the spontaneous release of $[^3H]-5-hydroxytryptamine$ ($[^3H]-5-HT$) during normoxic/normoglycemic or hypoxic/hypoglycemic period were studied in the rat hippocampal slices. The hippocampus was obtained from the rat brain and sliced $400\;{\mu}m$ thickness with the tissue slicer. After 30 min's preincubation in the normal buffer, the slices were incubated for 30 min in a buffer containing $[^3H]-5-HT$ ($0.1\;{\mu}M,\;74{\mu}Ci/8\;ml$) for uptake, and washed. To measure the release of $[^3H]-5-HT$ into the buffer, the incubation medium was drained off and refilled every ten minutes through sequence of 14 tubes. Induction of glucose/oxygen deprivation (GOD; medium depleting glucose and gassed with 95% $N_2/5%\;CO_2$) was done in 6th and 7th tube. The radioactivities in each buffer and the tissue were counted using liquid scintillation counter and the results were expressed as a percentage of the total radioactivities. When slices were exposed to GOD for 20 mins, the spontaneous release of $[^3H]-5-HT$ was markedly increased and this increase of $[^3H]-5-HT$ release was blocked by adenosine ($10\;{\mu}M$) or DL-2-amino-5-phosphonovaleric acid (APV; $30\;{\mu}M$). Adenosine $A_1$ receptor specific antagonist, 8-cyclopentyl-1,3-dipropylxanthine (DPCPX) exacerbate GOD-induced increase of spontaneous release of $[^3H]-5-HT$. These results suggest that Adenosine may play a role in the GOD-induced spontaneous release of $[^3H]-5-HT$ through adenosine $A_1$ receptor activity.

• The Korean Journal of Pharmacology
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• v.29 no.1
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• pp.9-22
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• 1993

To evaluate the protective effects of calcium antagonists, oxygen radical scavengers and excitatory amino acid (EAA) antagonist on the ischemic brain damage, we induced in vitro ischemic condition (namely, lack of oxygen and glucose) to rat hippocampal slices. And the degree of ischemic damage was determined by assaying changes in biochemical parameters such as ATP content and lactate ralease, MDA production in the presence or absence of the various drugs. During experimental ischemia for up to 60 min, ATP content was decreased and the amount of lactate release was markedly increased time-dependently. By changing the reaction medium which contained oxygen and glucose those biochemical parameters were recovered. But the recovery was not complete in this experimental condition. In the same ischemic conditions verapamil and vitamine E prevented the decrease of ATP content and the increase of lactate release from the slices. And verapamil and diltiazem decreased MDA release to the reaction medium. Superoxide dismutase (SOD) and MK-801 (as EAA receptor antagonist) protected the decrease of ATP content and reduced MDA release in 20 min ischemic condition, but glutathione affected ATP content and lactate release at the same condition. When oxygen and glucose were resupplied for 20 min after ischemic condition, verapamil showed the protective effect on the changes of ATP content and lactate release, and vitamine E decreased lactate release (at 20 min ischemia) and MDA release (at 60 min ischemia). These results showed that calcium antagonist and vitamine E protect the ischemic biochemical changes from rat hippocampal slices and calcium antagonist is more potent than vitamine E to protect the ischemical brain damege.

• Journal of Advanced Marine Engineering and Technology
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• v.18 no.2
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• pp.91-96
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• 1994

Intake gases other than air, which is composed of oxygen, nitrogen, carbon dioxide, and argon, are used to study their effects on the performance of the diesel engine experimentally. The engine is operated at constant speed and fixed fuel injection timing, and cylinder pressure and heat release rate are measured at various intake gas compositions. The results show that increase of oxygen concentration improves the performance of the engine generally. The adverse effect is observed when the oxygen concentration is increased over the critical oxygen concentration of this test, mainly because of the over-shortened ignition delay. Increase of carbon dioxide concentration degardes the performance of the engine, mainly due to the lower specific heat ratio of carbon dioxide. Adding argon gas to the intake gas improves the overall performance. Finally, it is found that two most influencing factors affecting the performance of the diesel engine in this study are ignition delay and speific heat ratio of the intake gas.

• Journal of Navigation and Port Research
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• v.36 no.6
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• pp.513-519
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• 2012

Understanding the behavior of pollutants in the marine environment is essential for coping with the marine pollution problems such as eutrophication. In this study, the effects of environmental parameters on phosphorus release from marine sediment to sea water were investigated. The environmental parameters such as pH in the range of 7 to 9, temperature from 10 to 20C and dissolved oxygen levels (DO) renging 0.7 to 7.0mg/L were examined. Phosphorus release data were taken from batch tests excluding biotic effects, and analyzed using a first-order kinetic model. The effects of environmental parameters were quantified using a statistical methodology. High pH, high temperature, and low DO increased phosphorus release from the sediment to sea water. pH from 7 to 9, temperature from 10 to $20^{\circ}C$, or DO from 7.0 to 0.7 mg/L magnified the equilibrium phosphorus concentration up to 2~3 times.

• Journal of Korean Society on Water Environment
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• v.21 no.6
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• pp.595-601
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• 2005

In this research, effects of water circulation on phosphorus release from sediment into water body were studied. Sediments sampled at the Daechung Lake were used for the column experiments with circulation and non-circulation conditions. Deaeration coefficient, $K_1$ and reaeration coefficient, $K_2$ of non-circulation condition were 0.133 and 0, respectively, while $K_1$ and $K_2$ for circulation condition were 0.46 and 0.018, respectively. Oxidation Reduction Potential (ORP) showed a linear relationship with dissolved oxygen (DO) when DO is over 2 mg/L. Phosphorus concentration induced by phosphorus release from sediment was highly dependent upon DO, ORP, and pH. Under anaerobic condition, phosphorus release rate was higher for $Fe^{2+}$-bounded phosphorus compared to that of $Ca^{2+}$-bounded phosphorus.

• Journal of Ecology and Environment
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• v.38 no.3
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• pp.319-326
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• 2015

This study investigates the behavioral characteristics and forms of phosphorus in the sediment according to the oxygen condition (aerobic/anaerobic). In the behavioral characteristics analysis, Al-P and Fe-P concentrations were the highest among the forms of inorganic phosphorus, and therefore had the strongest impact on sorption and release corresponding to environmental condition changes. In the experimental investigation of the inorganic forms of phosphorus in the sediment according to the oxygen condition, we determined that the forms of inorganic phosphorus did not greatly affect the sorption or release reaction because the distribution ratios of the inorganic forms remained constant corresponding to changes of dissolved oxygen (DO) conditions. In contrast, the forms of organic phosphorus in the sediments affected both sorption and release. Furthermore, labile-P and moderately labile-P forms were the major mechanisms of sorption in sediment. Moderately labile-P was the greatest contributor to phosphorus release action in sediment. As environmental changes are important for the behavioral characteristics of phosphorus in sediment, the forms of phosphorus should be considered to have a greater effect, especially in the organic phosphorus case. Therefore, based on the present study results, sediment evaluation aimed at controlling internal pollutants in reservoirs should include an examination of the forms of phosphorus present, as well as the release characteristics of environmental changes, which are influential factors of phosphorus control. Further research in this field is required.