http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
이시훈,박주식,임영준,김형택 ( Si Hyun Lee,Chu Sik Park,Yeoung Jun Yim,Hyeong Taek Kim ) 한국화학공학회 1996 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.34 No.1
Ash and deposits were made using Alaska sub-bituminous coal in a drop tube furnace(DTF) and the effects of their compositions on fusion were compared with those of the ashes prepared from the ASTM aching procedure. It has been found that the ASTM ash includes alumina, silica, mullite, and Ca compounds as crystalline phases, whereas the DTF ash includes spherical drops with K, Fe, and Ca condensed on the surface. In a DTF ash, only mullite existed as crystalline phase. `Che deposits existed as glass phases which were formed by solidification from melts, and Fe was transformed to Fe^(3+) silicate and Si was concentrated on the lower part of the deposit. This fact indicates that, among various inorganic elements in coal, Si controls the fusion. Although it was initially predicted that Alaska coal ash have strong slagging propensity based on the results of ASTM ash characterization, the results of analysis of the DTF deposits shows that the deposits can be easily removed from the heat transfer area because it is enriched with Ca which reduces the strength of its adhesion to the solid surface.
이시훈,손응권,박석환 ( Si Hyun Lee,Eung Kwon Shon,Suk Whan Park ) 한국화학공학회 1995 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.33 No.6
Domestic anthracite and imported bituminous coals were treated according to the molten caustic leaching procedures and changes in their organic structures were investigated. The investigation was conducted through ultimate analysis, functional group analysis using IR/NMR, and vitrinite reflectance measurements and marceral analysis with microphotometer. The results of analyses showed that the H/C ratio and the highly reactive aliphatic hydrocarbon groups linked with aromatic hydrocarbons decreased and the vitrinite reflectance increased with treatment. These are changes observed when carbonization occurs. However, the results of the observation of maceral surface showed that the surface of the organic groups was severely damaged and the anisotropy, which should increase with carbonization, decreased. The decrease in the combustion temperature and the increase in combustion reactivity were attributed to the physical changes on the surface of organic groups rather than to the chemical changes such as break down in the organic groups.
이시훈,손응권 ( Si Hyun Lee,Eung Kwon Shon ) 한국화학공학회 1994 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.32 No.3
Korean anthracite, JangSung coal, has been treated with molten caustic leaching using several reaction temperatures, NaOH/coal ratios and particle sizes of raw coals. Ash removal rates, variations in combustion temperatures and combustion rates after treatment were investigated by using TGA(Thermogravimetric Analyser). Results for a typical bituminous coal and a foreign anthracite at a fixed condition of 390℃, NaOH/coal ratio of 4 were also compared with that for a JangSung coal. It had been found for JangSung coal that the ash removal rates were 64-88% and the combustion peak temperature lowered about 150℃ after treatment so that the combustion range of treated coal became similar to that of bituminous coal. Variations in particle size, surface area after treatment were measured and the ratio of volatile matter to fixed carbon(VM/FC) representing coal rank were calculated. The relationship between VM/FC ratio and the variations in combustion temperatures after treatment was discussed briefly.
생물화공 에너지 / 환경 : 알칼리 금속화합물을 이용한 석유코크스의 활성화와 SO2 흡착특성 : 수분 영향
이시훈(Si Hyun Lee),임영준(Young Jun Lim),이규철(Kyu Chol Lee) 한국화학공학회 1999 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.37 No.5
Activation of petroleum cokes by alkali metal compounds and SO₂adsorption characteristics were investigated. Near complete removal(>95%) of sulfur and ash, hydrogen evolution of purity more than 95%, and reductions of particle size were major features of alkali activation. Adsorption capacities of activated carbons at low temperature(30℃) were not increased with moisture contents, and this is opposite results reported with the activated carbon fiber. It was found that the moisture contents above saturation level cause condensation on pore surfaces of activated carbons due to the smaller number of free sites and lower adsorption/desorption rates than the activated carbon fiber, and also found that the optimum adsorption temperatures must be selected with moisture contents. Typical results showed that 100℃ for the 10% moisture, and 30℃ for the 4% moisture were optimum conditions respectively. Alkali activated carbon from petroleum cokes showed larger SO₂adsorption capacity than the conventional activated carbon due to its wide ranges of pore size and its hydrophilic surface functional groups. SO₂adsorption capacity was about 200 ㎎SO₂/gAC/6 hr without pretreatment such as oxidation and thermal treatment.
이시훈(Si Hoon Lee),강은석(Eun Seok Kang),이광은(Kwang Eun Lee),김하동(He Dong Jin),최성희(Seung Hee Choi),김대중(Dae Jung Kim),안철우(Chul Woo Ahn),차봉수(Bong Soo Cha),임승길(Sung Kil Lim),이현철(Hyun Chul Lee),허갑범(Kap Bum Huh) 대한내과학회 2002 대한내과학회지 Vol.63 No.1
Background: This study was initiated to evaluate the prevalence of metabolic syndrome and its components as risk factors for cardiovascular disease according to insulin resistance in the Korean adult population. Methods: This study was conducted as a branch of the Korean Metabolic Syndrome (KMS) Study: 1,091 individuals aged 30 79 years participating in medical check-up in Korea Association of Health (KAH) were included in this study. We checked fasting blood sugar, fasting insulin, proinsulin, lipid profiles (total cholesterol, triglyceride, LDL-cholesterol, HDL-cholesterol), body mass index, waist circumference, blood pressure, carotid intima-media thickness (IMT) and abdominal ultrasonography. We divided all of the examinees into three groups (insulin sensitive, intermediate, resistant tertiles) according to their degree of insulin resistance and correlated this with the prevalence of metabolic syndrome. Results: The relative risk of metabolic syndrome was 84.1-fold higher in the insulin resistant tertile group compared to the insulin sensitive tertile group. Diabetes mellitus or impaired fasting glucose (IFG) was 10.2-fold; hypertension, 1.8-fold; dyslipidemia, 2.8-fold; hypercholesterolemia, 2.5-fold; fatty liver, 3.0-fold. Abdominal obesity rather than general obesity was more contributory to insulin resistance. Conclusion: Although this is a cross-sectional study, we can show that insulin resistance is one of the most-striking risk factors in metabolic syndrome and can be used as a predictor of cardiovascular diseases. Furthermore, we should monitor the healthy insulin-resistant population to prevent ongoing cardiovascular diseases. More prolonged data should be gained to refine the correlations of insulin resistance to metabolic syndrome.(Korean J Med 63:54-60, 2002)