• Transactions of the Korean hydrogen and new energy society
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• v.1 no.1
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• pp.15-23
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• 1989

The selective separation of hydrogen from gas mixture containing hydrogen was experimentally studied using $LaNi_5$. The capacity and the rate of hydrogen separation, the purity of recovered hydrogen and the optimum condition of the regeneration of deactivated $LaNi_5$ were investigated. The separation rate and the recovery ratio of hydrogen were slowly decreased with the increase of the number of hydrogen absorption cycle. It was found that this result comes from the deactivation of $LaNi_5$ partly because of the blocking of hydrocarbon compounds in the $LaNi_5$ lattice and partly because of the poisoning of $LaNi_5$ surface by carbon monoxide contained in the gas mixture. The optimum condition for the regeneration of deactivated $LaNi_5$ was obtained by heating in a vacuum to about 637 K. The recovery ratio of hydrogen at the optimum condition was observed to be about 80%. The rates of hydrogen separation were measured in the ${\alpha}$-phase and two phase regions. The rate equations could be expressed as follows ; ${\alpha}$ - phase : $$-\frac{dP{_{H_2}}}{dt}=9.836{\times}10^{-3}(P{_{H_2}}_{-P_{eq}})$$ two phase region : $$-\frac{dP_{H{_2}}}{dt}=1.6909{\times}10^2\exp(-17560/RT)(P{_{H_2}}_{-P_{eq}})$$.

• Applied Chemistry for Engineering
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• v.1 no.2
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• pp.215-223
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• 1990

The effects of sulfur on the catalytic reaction between CO and NO on polycrystalline Pt surface, which is very important in the development of catalyst for automobile exhaust gas control, have been studied using thermal desorption spectrometry(TDS) under ultra-high vacuum(UHV) conditions. Sulfur weakened both the adsorptions of CO and NO by direct site blocking and indirect electronic effect. S(a) desorbing below 800 K gave little effect on reaction activity whereas S(a) desorbing above 800 K, which adsorbs as an atomic state, gave much effect on it. The adsorbed sulfur existed on the surface of platinum in the form of islands, and also reduced the adsorption energies of adsorbates by the long-ranged electronic effect. The platinum catalyst in the reaction between CO and NO was poisoned selectively by S(a), poisoning firstly the active sites of this reaction.

• Journal of The Korean Society of Clinical Toxicology
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• v.11 no.2
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• pp.81-88
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• 2013

Purpose: The aim of this study is to investigate current status, indications, and complications of hyperbaric oxygen therapy. Methods: A retrospective investigation of patients who underwent hyperbaric oxygen therapy at a university medical center from September 2004 to August 2013 was conducted based on patients' medical records and results of an email survey for 99 emergency centers. Results: During the study period, a total of 233 patients underwent hyperbaric oxygen therapy. Indications for hyperbaric oxygen treatment of illness or injury were as follows: 1) 151 cases of acute carbon monoxide poisoning(65.4%), 2) flap wound management, including 42 cases(18.2%), 3) skin care transplanted, including 23 cases(10.4%), 4) Burger's disease, including 5 five cases(2.1%), respectively. Total application time$^*$ frequency was 1,088 and total time was 1,239 hours. Among 233 patients who underwent hyperbaric oxygen therapy, 32 patients(13.7%) had complications: 1) otalgia in 21 cases(9.0%), 2) mastoiditis?in six cases(2.6%), 3) hemotympanum in five cases(2.1%), respectively. There were only 8 emergency centers that currently had an operational hyperbaric oxygen chamber in 77 emergency centers(10.4%). Conclusion: Indications identified through this study showed difference from current indications worldwide. It seems necessary that physicians' perception regarding application of hyperbaric oxygen therapy for more indications be changed and improved. A hyperbaric chamber capable of providing respiratory assistance and intensive care is also needed. A good network for sharing treatment experiences and a specialized team for administration of hyperbaric oxygen therapy is also required.

• Journal of the Korean Institute of Gas
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• v.20 no.6
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• pp.89-94
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• 2016

The number of camping population and sites are rapidly increasing with to the expansion of camping culture and the advancement of leisure culture. It is necessary to develop an effective strategy of safety management, as a lot of accidents occur due to the increase of population and sites for camping. Particular attention needs to be paid for accident prevention in the increasing accidents of explosion awing to the overheating of bytane gas, and carbon monoxide poisoning due to the use of non-ventilated areas. In this study, the direction of safety management strategy is analyzed by a survey and analysis of risk factors in campsite about gas facilities and gas appliances in camp site. Accordingly, some directions are suggested. Conclusively, it is expected that the results of this study could help to improve efficiency management for camping.

• Journal of Environmental Health Sciences
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• v.49 no.3
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• pp.149-158
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• 2023

Background: Injury is one of the major health problems in South Korea. Few studies have evaluated both intentional and unintentional injury when investigating the association between exposure to air pollutants and injury. Objectives: We aimed to explore the association between short-term exposure to ambient air pollution and years of life lost (YLLs) due to injury. Methods: Data on daily YLLs for 2002~2019 were obtained from the the Death Statistics Database of the Korean National Statistical Office. This study estimated short-term exposure to particulate matter with an aerodynamic diameter of <10 ㎛ (PM₁₀), particulate matter with an aerodynamic diameter of <2.5 ㎛ (PM_2.5), sulfur dioxide (SO₂), nitrogen dioxide (NO₂), carbon monoxide (CO), and ozone (O₃). This time series study was conducted using a generalized additive model (GAM) assuming a Gaussian distribution. We also evaluated a delayed effect of ambient air pollution by constructing a lag structure up to seven days. The best-fitting lag was selected based on smallest generalized cross validation (GCV) value. To explore effect modification by intentionality of injury (i.e., intentional injury [self-harm, assault] and unintentional injury), we conducted stratified subgroup analyses. Additionally, we stratified unintentional injury by mechanism (traffic accident, fall, etc.). Results: During the study period, the average daily YLLs due to injury was 307.5 years. In the intentional injury, YLLs due to self-harm and assault showed positive association with air pollutants. In the unintentional injury, YLLs due to fall, electric current, fire and poisoning showed positive association with air pollutants, whereas YLLs due to traffic accident, mechanical force and drowning/submersion showed negative associations with air pollutants. Conclusions: Injury is recognized as preventable, and effective strategies to create a safe society are important. Therefore, we need to establish strategies to prevent injury and consider air pollutants in this regard.

• Journal of Preventive Medicine and Public Health
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• v.15 no.1
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• pp.145-151
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• 1982

Breslau's report on the two stillbirths induced by illuminating gas poisoning made many investigators explore the hazards. of carbon monoxide(CO) poisoning to pregnancy. The pregnant woman, her fetus, and the newborn infant have been identified to be particularly vulnerable to CO even in low concentration. Several factors, such as placental barrier, membrane resistance of maternal and fetal red blood cells etc., were considered to be related to the delayed elimination of CO from fetus. Slower elimination of CO from fetus than from mother was confirmed in several in vivo studies. But there are few studies which have confirmed the difference of carboxyhemoglobin (HbCO) dissociation in adult and fetal bloods. Author investigated the effects of hemoglobin itself on the elimination of CO from mother and fetus. By observing the difference of CO dissociation from adult and fetal hemoglobin at the various partial pressures of oxygen, the author tries to suggest the base of the proper treatment measure for the CO poisoning of pregnant woman and newborn infant. The results were as follows: 1. The total hemoglobin amounts of adults and fetal bloods were $16.1{\pm}0.50gm%\;and\;15.7{\pm}0.32gm%$, respectively. The fetal hemoglobin proportions in adult and fetal bloods were $1.2{\pm}0.15%\;and\;72.7{\pm}3.01%$, respectively. 2. Adult and fetal bloods saturated by CO to 100% HbCO were exposed to ambient air$(21%\;O_2),\;100%\;O_2\;and\;3\;ATAO_2$. After 30 minutes exposure, the HbCO saturations of adult blood were 96.7%, 70.9%, and 52.8%, respectively, and those of fetal blood were 98.5%, 76.1%, and 62.2%, respectively. HbCO dissociation was proportional to the partial pressure of oxygen and the most marked dissociation was shown under 3 ATA $O_2$, HbCO dissociation of fetal blood was slower than that of adult blood in all conditions. According to the above results, it is possible that CO poisoning make more serious damage to the fetus and newborn infant than to the adult due to the delayed dissociation of HbCO. Thus in the treatment of CO poisoning of pregnant woman and newborn infant, hyperbaric oxygen therapy seems to be the most eflective treatment measure, but the duration of hyperbaric oxygenation should be lengthened accordingly.

• Korean Journal of Crystallography
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• v.16 no.1
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• pp.43-53
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• 2005

The dihydrido P-C-P pincer complex, $IrH_2{C_6H_3-2,6-(CH_2PBu_2^t)_2}$ (1), was successfully prepared from the reaction of the hydrochloride complex, $IrClH (C_6H_3-2,6-(CH_2PBu_2^t)_2}$, and super acid $(LiBEt_3H)$ under 1 atm of hydrogen in pentane solution at room temperature and followed by Heating at $130^{\circ}C$ in vacuo. Jensen recently found that the dihydrido P-C-P pincer complex 1 is a highly active homogeneous catalyst for the transfer dehydrogenation of alkanes with unusual longterm stability at temperatures as high as $200^{\circ}C$. The treatment of dihydrido complex 1 with nitrogen, water, carbon dioxide, and carbon monoxide in presence of tert-butylethylene (the) at room temperature in an appropriate solution gave the dinitrogen complex, $[Ir{C-6H_3-2,6-(CH_2PBu_2^t)_2}]_2({\mu}-N_2)$ (2), the hydrido hydroxyl complex, $IrH(OH){C_6H_3-2,6-(CH_2PBu_2^t)_2}$ (3), the carbon dioxide complex, $Ir({\eta}^2-CO_2) {C_6H_3-2,6-(CH_2PBu_2^t)_2}$ (including the bicarbonate complex, $IrH({\kappa}^2-O_2COH){C_6H_3-2,6-(CH_2PBu_2^t)_2}\;(4))$, and the carbonyl complex, $Ir(CO) {C_6H_3-2,6-(CH_2PBu_2^t)_2}\;(5)$ (including the carboxyl complex, $IrH(C(O)OH) {C_6H_3-2,6-(CH_2PBu_2^t)_2}\;(6))$, in good yield, respectively. These P-C-P iridium complexes were isolated and characterized by $^1H,\;^{13}C,\;^{31}P\; NMR$, and IR spectroscopy. In addition, the complexes (1-6) were characterized by a single crystal X-ray crystallography. These complexes account for these small molecules' inhibition of dehydrogenation of alkanes catalyzed by the dihydrido complex 1.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1972.03a
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• pp.6-7
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• 1972

The air pollutants can be classified into the irritant gas and the asphixation gas, and the irritant gas is closely related to the otorhinolaryngological diseases. The common irritant gases are nitrogen oxides, sulfur oxides, hydrogen carbon compounds, and the potent and irritating PAN (peroxy acyl nitrate) which is secondarily liberated from photosynthesis. Those gases adhers to the mucous membrane to result in ulceration and secondary infection due to their potent oxidizing power. 1. Sulfur dioxide gas Sulfur dioxide gas has the typical characteristics of the air pollutants. Because of its high solubility it gets easily absorbed in the respiratory tract, when the symptoms and signs by irritation become manifested initially and later the resistance in the respiratory tract brings central about pulmonary edema and respiratory paralysis of origin. Chronic exposure to the gas leads to rhinitis, pharyngitis, laryngitis, and olfactory or gustatory disturbances. 2. Carbon monoxide Toxicity of carbon monoxide is due to its deprivation of the oxygen carrying capacity of the hemoglobin. The degree of the carbon monoxide intoxication varies according to its concentration and the duration of inhalation. It starts with headache, vertigo, nausea, vomiting and tinnitus, which can progress to respiratory difficulty, muscular laxity, syncope, and coma leading to death. 3. Nitrogen dioxide Nitrogen dioxide causes respiratory disturbances by formation of methemoglobin. In acute poisoning, it can cause pulmonary congestion, pulmonary edema, bronchitis, and pneumonia due to its strong irritation on the eyes and the nose. In chronic poisoning, it causes chronic pulmonary fibrosis and pulmonary edema. 4. Ozone It has offending irritating odor, and causes dryness of na sopharyngolaryngeal mucosa, headache and depressed pulmonary function which may eventually lead to pulmonary congestion or edema. 5. Smog The most outstanding incident of the smog occurred in London from December 5 through 8, 1952, because of which the mortality of the respiratory diseases increased fourfold. The smog was thought to be due to the smoke produced by incomplete combustion and its byproduct the sulfur oxides, and the dust was thought to play the secondary role. In new sense, hazardous is the photochemical smog which is produced by combination of light energy and the hydrocarbons and oxidant in the air. The Yonsei University Institute for Environmental :pollution Research launched a project to determine the relationship between the pollution and the medical, ophthalmological and rhinopharyngological disorders. The students (469) of the "S" Technical School in the most heavily polluted area in Pusan (Uham Dong district) were compared with those (345) of "K" High School in the less polluted area. The investigated group had those with subjective symptoms twice as much as the control group, 22.6% (106) in investigated group and 11.3% (39) in the control group. Among those symptomatic students of the investigated group. There were 29 with respiratory symptoms (29%), 22 with eye symptoms (21%), 50 with stuffy nose and rhinorrhea (47%), and 5 with sore thorat (5%), which revealed that more than half the students (52%) had subjective symptoms of the rhinopharyngological aspects. Physical examination revealed that the investigated group had more number of students with signs than those of the control group by 10%, 180 (38.4%) versus 99 (28.8%). Among the preceding 180 students of the investigated group, there were 8 with eye diseases (44%), 1 with respiratory disease (0.6%), 97 with rhinitis (54%), and 74 with pharyngotonsillitis (41%) which means that 95% of them had rharygoical diseases. The preceding data revealed that the otolaryngological diseases are conspicuously outnumbered in the heavily polluted area, and that there must be very close relationship between the air pollution and the otolaryngological diseases, and the anti-pollution measure is urgently needed.

• The Journal of Internal Korean Medicine
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• v.38 no.5
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• pp.628-640
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• 2017

Purpose: To describe the effectiveness of traditional Korean medicine (TKM) on the patients with secondary dementia (case 1: Rt. MCA infarction; case 2: traumatic subacute subdural hemorrhage and traumatic intracranial hemorrhage; case 3: delayed encephalopathy after carbon monoxide poisoning). Methods: We used a complete TKM treatment. The acupoints used were as follows: acupoints frequently used in hemiparesis (GV20, GV24, ST4, LI11, LI14, ST36, GB34, SP9, and LR3), and we used herbal medicine (補腎益腦湯加味, Boshiniknoe-tang-gami). The efficacy was evaluated using the Mini-Mental State Examination for Dementia Screening (MMSE-DS) and the Modified Barthel Index (MBI). Results: After treatment, the total MMSE-DS score was increased from 14 to 24 (case 1), 14 to 19 (case 2), and 0 to 17 (case 3). The total K-MBI was increased from 30 to 44 (case 1), 82 to 86 (case 2), and 30 to 86 (case 3) Conclusions: We suggest that TKM could positively influence cognition and improve activity of daily living (ADL). This study has limitations, so further studies are needed.

• Membrane Journal
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• v.32 no.6
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• pp.442-455
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• 2022

High-temperature polymer electrolyte membrane fuel cell (HT-PEMFC) has been studied as an alternative to low-temperature PEMFC due to its fast activation of electrodes and high resistance to electrode poisoning by carbon monoxide. It is highly required to develop stable PEMs operating at high temperatures even doped by ion-conducting materials for the development of high-performance and durable HT-PEMFC systems. A number of studies have been conducted to develop polybenzimidazole (PBI)-based PEMs for applications in HT-PEMFC due to their high interaction with doped ion-conducting materials and outstanding thermomechanical stability under high-temperature operation. This review focused on the development of PBI-based PEMs showing high performance and durability. Firstly, the characteristic behavior of PBI-based PEMs doped with various ion-conducting materials including phosphoric acid was systematically investigated. And then, a comparison of the physicochemical properties of the PEMs according to the different membrane manufacturing processes was conducted. Secondly, the incorporation of porous polytetrafluoroethylene substrate and/or inorganic composites to PBI matrix to improve the membrane performances was studied. Finally, the construction of cross-linked structures into PBI-based PEM systems by polymer blending method was introduced to improve the PEM properties.