The carbon anode material for lithium-ion battery was prepared by pyrolysis fuel oil and waste polyethylene terephthalate (PET) additive. The pitch was synthesized as a medium material for carbon anode by heat treatment. The waste PET additive improved the softening point and thermal stability of the pitch. La and Lc of the anode material (heat-treated pitch) increased at higher treatment temperature but decreased by waste PET additive. The electric capacity was evaluated based on effects of defective cavity and developed graphite interlayer, respectively. When the La and Lc of the anode material decreased, the electric capacity by cavity increased based on defective graphite structure. Therefore, the addition of waste PET causes the improved capacity by the cavity. The anode material which has a high efficiency (over 95%) and C-rate (95%, 2 C/0.1 C) was obtained by controlling the process of heat treatment and PET addition. The mechanism of lithium-ion insertion was discussed based on effects of defective cavity and developed graphite interlayer.

본 연구에서는 합성가스 CO를 생산하기 위해 저급 석탄-CO2 촉매 가스화 실험을 수행하였 다. 제조된 CO가스 특성은 키데코 탄과 신화 탄에 KOH, K2CO3, Na2CO3 촉매들의 화학적 활성화 방 법을 이용하여 조사되었다. CO 제조공정은 석탄과 화학약품 활성화 비율, 가스 유량, CO2 전환 반응온 도와 같은 실험 변수 분석을 통해 최적화되었다. 제조된 합성 가스는 가스 크로마토그래피(GC)에 의해 분석 되었다. 실험조건 T = 950 °C, CO2 유량 100 cc/min에서, 20 wt% Na2CO3가 혼합된 키데코 탄 에 대해 98.6%, 20 wt% KOH가 혼합된 신화탄에 대한 98.9% CO2 전환율을 얻었다. 또한, 저급 석탄-촉매 가스화 반응은 동일한 공급 비와 반응 조건에서 97.8%, 98.8%의 CO 선택도를 얻었다.

The objective of this study was to evaluate associations between airborne manganese and blood manganese in a general population of South Korean adults. The concentrations of airborne manganese in total suspended particulate (TSP) were calculated from data obtained from ambient air-monitoring stations (AAMSs) located in South Korea. Blood manganese data obtained Korean National Health and Nutrition Examination Survey (KNHANES) using a rolling sampling design involving a complex, stratified, multistage, probability cluster survey of a representative sample of the non-institutionalized civilian population of South Korea. Airborne manganese geometric means was 46.10 ng/㎥, blood manganese geometric means were 1.19 ㎍/㎗ for male and 1.40 ㎍/㎗ for female. In multiple linear regression analysis of log transformed blood manganeseas a continuous variable on airborne manganese, after adjusting for covariates including gender, age, job, smoking and drinking status, education level, BMI (body mass index). Airborne manganese was positively associated with blood manganese with statistical significance. The present study confirms that airborne manganese is a possible contributor to the increase of blood manganese in the adult general population.

The purpose of this study was to investigate Rn concentration and annual radiation exposure level in the basement and first floor. The Rn Cup monitors were placed in different environments such as shopping stage, office building, Apartment, Hospital , house in Seoul from March 1996 to April 1997 and CR-39 films were collected every two months. The mean radon concentration in the basement of house(88.6 Bq/㎥) showed the highest level among the areas, while radon concentration on the first floor of house(50.5 Bq/㎥) showed the higher than other areas. The annual radiation exposure dose that person on the floor / in the basement of differential place in the seoul can be exposed during living was estimated from 24.11 to 87.64 mRem/yr. This radiation dose is significantly lower than 130mRem maximum radiation dosage from the radon nuclide prescribed by the ICRP, with respect to the overall average exposure of the working adult. this study indicated that possible radon sources on the first floor / in the basement areas are radon intrusion from soil gas, construction materials, or ground water leaking. Further study is needed to quantitatively assess major contributions of radon-222 and health effect to radon exposure.