이산화티타늄 수용액에서 유기인계 살충제에 광분해

김병관,김종향 ( Byung Kwan Kim,Jong Hyang Kim ) 한국공업화학회 1995 공업화학 Vol.6 No.6

이산화티타늄을 촉매로 하여 물속에 함유되어 있는 유기인계살충제인 디메톤-s-메틸, 다이아지논, 파라티온, 펜토에이트 그리고 이피엔을 200W UV램프를 이용하여 광분해시켰다. pH 4, 7, 9, 11 조건에서는 단지 UV만 조사시켰을 때와 UV와 촉매를 함께 조사시켰을 때의 유기인계 살충제의 분해과정, 촉매의 양과 초기 pH 조건에 따른 분해과정을 실험하였다. 유기인계살충제들의 분석은 NPD가 부착된 가스크로마토그래피로 분석하였다. UV만 조사시켰을 때보다 UV와 촉매를 함께 사용하여 분해시켰을 때 pH 7에서 다이아지논을 제외한 나머지 물질들은 거의 2시간 정도에서 완전분해됨을 알았다. TiO₂의 양이 500㎎에서는 다이이지논과 파라티온의 제거율은 50% 정도 분해를 나타내었다. 초기 pH 조건에서, 광분해는 pH 6과 8을 제외하고는 산성조건과 염기성조건에서 분해가 잘 일어났다. The photodecomposition of organophosphorus(org-p) insecticides, such as demeton-s-methyl, diazinon, parathion, phenthoate and EPN using titanium dioxide(anatase) aqueous suspension was performed with a high pressure UV lamp. It was examined that the effects of UV irradiation with and without TiO₂ powder at pH 4, 7, 9, 11, amount of TiO₂ powder, and initial pH solution. The analysis of org-p insecticides was carried out by gas chromatograph with nitrogen-phosphorus detector. UV irradiation with TiO₂ powder could decompose the org-p completely in about 2hrs without diazinon at pH 7. It shown that diazinon and parathion decompose 50% using 500㎎ of TiO₂. Initial pH condition, photodecomposition increased both acidic and basic solution except pH 6 and 8.

LCA(Life Cycle Assessment)의 연구현황과 금후의 과제

김병관,Kim, Byeong-Gwan 재료연구소 1998 機械와 材料 Vol.10 No.3

Na/Al 비와 양생온도가 지오폴리머의 백화억제에 미치는 영향

김병관,허예은,전철민,이수정,Kim, Byoungkwan,Heo, Ye-Eun,Chon, Chul-Min,Lee, Sujeong 한국자원리싸이클링학회 2018 資源 리싸이클링 Vol.27 No.6

Efflorescence is a white deposit of powders in the surface of cement concrete which can also occur in geopolymers. Efflorescence occurs when sodium ions in alkali activator react with atmospheric carbon dioxide to form sodium carbonate components. In this study, we investigated whether the secondary efflorescence can be reduced by controlling the Na/Al mole ratio or by changing the curing temperature and heat curing time in fly ash-based geopolymers. The 28 days compressive strength in geopolymers having Na/Al ratio of 1.0 was higher than geopolymers having Na/Al ratio of 0.8. The strength increased with the increasing curing temperature and longer heat curing time. On the other hand, efflorescence was lower when the curing temperature was high and the heat curing time was longer in the geopolymers having Na/Al ratio of 1.0. The geopolymers having Na/Al ratio of 0.8 showed accelerated efflorescence occurrence than the geopolymers having Na/Al ratio of 1.0. In order to reduce the occurrence of the secondary efflorescence of fly ash-based geopolymers, it will be advantageous to maintain the Na/Al ratio at 1.0, increase the curing temperature, and lengthen the heating curing time.

석탄가스화 복합발전 슬래그의 알칼리 활성 시멘트로서의 가능성

김병관,이수정,전철민,최홍식,Kim, Byoungkwan,Lee, Sujeong,Chon, Chul-Min,Choi, Hong-Shik 한국자원리싸이클링학회 2018 資源 리싸이클링 Vol.27 No.2

Integrated gasification combined cycle (IGCC) is a next generation energy production technology that converts coal into syngas with enhanced power generation efficiency and environmental performance. IGCC produces almost coal gasification slag as the solid by-product. IGCC slag is generated about 140,000 tons for a year although recycling of it is still in the early stages. We evaluated the potential of IGCC slag which is generated from a pilot plant in South Korea as an alkali-activated cement. Samples which were activated with the combined activator of sodium silicate solution and caustic soda had an average compressive strength of 4.5 MPa, showing expansion. Expansion of the alkali-activated slag was presumed to be caused by free CaO in the slag, although it was not detected by the ethylene glycol method. Samples that were activated with the combined activator of sodium aluminate and caustic soda had an average compressive strength of 10 MPa. Hydroxy sodalite and $C_3AH_6$ were found to be the new crystalline phases. IGCC slag can be used as an alkali-activated material, but the strength performance should be improved with proper mix design approach to calculate optimum proportions which can alleviate the expansion issue at the same time.

수식 졸 - 겔법에 의한 TiO2 - SiO2 분체합성 및 광촉매활성

김병관,수야철효 (水野哲孝),안정지 (安井至) ( Byung Kwan Kim,Noritaka Mizuno,Itaru Yasui ) 한국공업화학회 1996 공업화학 Vol.7 No.6

DCCA로 1-도데카놀을 이용한 수식 졸-겔법에 의한 TiO₂-SiO₂계분체를 합성하였으며, 이들 합성분체에 대한 characterization과 광활성촉매에 대해 검토하였다. 500℃까지의 감량변화는 TiO₂단독분체가 33.0wt%, TiO₂/SiO₂의 몰비가 75/25, 50/50 및 25/75인 분체는 각각 67.0wt%, 70.0wt% 및 73.0wt%, 그리고 SiO₂단독분체는 42.5wt%이였다. 이들 탈리는 거의 대부분이 유기물질이였다. 합성직후의 분체는 TiO₂단독분체를 제외하고는 무정형화합물이였고, 아나타아제의 루틸로의 상전이는 SiO₂에 의해 억제되었다. 합성직후의 분체는 입자의 형태가 관찰되지 않았으나, 600℃, 1시간 가열에 의한 TiO₂단독분체, TiO₂/SiO₂의 몰비가 75/25 및 50/50인 분체는 모두 서브미크론의 입자를 보였으며, 몰비가 25/75의 분체 및 SiO₂단독분체는 여전히 벌크상태였다. 비표면적 역시 SiO₂의 증가와 함께 증가하였으며, 세공크기 역시 SiO₂성분에 의존하였다. 그리고 이들 가열물의 광촉매활성은, TiO₂/SiO₂의 몰비가 75/25인 분체의 경우, 수소발생량으로 0.240μmol/h.g-cat.을 나타내었으며, TiO₂단독분체의 그것보다는 약 2.6배, 표준광촉매물질인 P-25(Degussa P-25)보다는 약 2.0배 가량 큰 값을 나타냈다. Various TiO₂-SiO₂ composite powders were prepared by the modified sol-gel method using 1-dodecanol as DCCA (Dryng Control Chemical Additive). Their characterizations were carried out and their photocatalytic catalysis was examined on the evolution reaction of hydrogen. The weight losses at 500℃ of only TiO₂ and SiO₂ powders were 33.0wt% and 42.5wt%, respectively, and those of the TiO₂/SiO₂ powders (TiO₂/SiO₂=25/75, 50/50 and 75/25) were about 70.0±3.0wt%. The released substances from the powders were almost organic matters. The as-prepared powders except only TiO₂powder were amorphous. Transformation of anatase to rutil was hindered by SiO₂ component and the crystallinity of anatase was decreased with increasing SiO₂ contents. The as-prepared powders were bulky states. By heating at 600℃ for 1 hr TiO₂-SiO₂ powders (TiO₂=100%, TiO₂/SiO₂=75/25,50/50) showed agglomerates consisted of particles in submicron, but those of TiO₂/SiO₂=25/75 and SiO₂=100% were still bulky states. Specific surface area of the powders heat-treated at 600℃ for 1hr was increased with SiO₂ contents and their pore sizes were also depended on SiO₂ contents. The photocatalytic activity of TiO₂/SiO₂=75/25 heat-treated at 600℃ for 1hr was 0.240mol/h.g-cat as H₂ evolution rate. This value was about 2.0 times that of P-25(Degussa P-25) as a standard photocatalyst.

벤처기업 투자 심사를 위한 정성 평가 지표의 유효성 검증: 사례연구

김병관,김완기,Kim, Byounggwan,Kim, Wanki 기술경영경제학회 2017 Journal of Technology Innovation Vol.25 No.4

최근 벤처캐피털의 운영 펀드 규모의 지속적 증가에 따라 투자 심사역의 업무도 대폭 증가하고 있다. 그러나 투자 판단은 심사역의 역량에 따라 많은 차이를 보이고 있다. 이에 본 연구는 '벤처 투자 실무 평가 지표'에 대한 후속 연구로서 투자 심사 평가 지표의 유효성을 검증하고자 하였다. 연구는 먼저 평가 지표를 표준화한 후, 100개 벤처 기업을 대상으로 t-검증을 실시한 결과, 투자 심사 평가 지표들은 유의미하였고 정성 평가 지표의 유효성 역시 약 85%의 적중률을 보였다. 따라서 본 연구결과가 향후 벤처기업 투자 의사 결정력 제고에 나름 기여할 수 있을 것으로 사료된다. As the size of venture firm's operating funds continues to increase, the scope of work of the investment jurisdiction is increasing dramatically as well. However, investment decisions vary widely, depending on the competence of the judges. This follow-up study recommends verifying the validity of the effectiveness of venture investments by validating the efficacy of assessing venture investment indexes. After verifying the assessment indexes for 100 venture firms, the study noted that the efficacy of the survey as a qualitative evaluation measure was approximately 85% hit, which can act as a yardstick for investment decisions. The results of this study can contribute toward the decision making power of venture companies in terms of investments.

크론병에서 항문 주위 병변의 임상상과 치료에 대한 반응

김현대 ( Kim Hyeon Dae ),김찬규 ( Kim Chan Gyu ),김지원 ( Kim Ji Won ),김상균 ( Kim Sang Gyun ),김병관 ( Kim Byeong Gwan ),김주성 ( Kim Ju Seong ),정현채 ( Jeong Hyeon Chae ),송인성 ( Song In Seong ) 대한소화기학회 2003 대한소화기학회지 Vol.42 No.2

Background/Aims: The aim of this study was to assess the clinical features and therapeutic responses of perianal lesions in Crohn`s disease. Methods: We retrospectively reviewed medical records of 94 cases with perianal lesions among 231 cases registered as Crohn`s disease in Seoul National University Hospital between January 1975 and June 2001. The cases were investigated after dividing into two different groups. One group included the cases registered between January 1975 and December 1996 and the other group between January 1997 and June 2001. Results: The perianal lesions were observed in 41% of the cases. Perianal lesions were more frequent in colonic Crohn`s disease after 1997, but not before 1996. Fistula was significantly prevalent, followed by abscess, fissure, and stricture. Perianal lesions preceded intestinal symptoms such as abdominal pain and diarrhea in 25% of the cases. The remission rate with non-specific conservative treatment (10%) was lower than that before 1996. The remission rate after specific treatment (77%) was higher than that after surgery (53%). In cases of specific treatment, cumulative relapse rates were 7% in 1 year and 39% in 5 years. Conclusions: Crohn`s disease should be considered in young male patients who have the refractory perianal lesions. Perianal lesions should be managed initially with medical treatment. (Korean J Gastroenterol 2003;42:128-133)

염증성 장질환에서 IL-10과 TNF-α 유전자의 단염기 다형성

김지원 ( Ji Won Kim ),김찬규 ( Chan Gyoo Kim ),김현대 ( Hyeon Dae Kim ),김병관 ( Byeong Gwan Kim ),김태호 ( Tae Ho Kim ),이국래 ( Kook Lae Lee ),이동호 ( Dong Ho Lee ),김주성 ( Joo Sung Kim ),정현채 ( Hyun Chae Jung ),송인성 ( In 대한소화기학회 2002 대한소화기학회 춘계학술대회 Vol.2002 No.-

<목적> 염증성 장질환의 병태생리에 중요한 역할을 하는 IL-10과 TNF-α유전자의 단염기 다형성과 염증성 장질환과의 연관성을 살펴봄으로써 염증성 장질환의 발생에 관여하는 유전적 원인을 규명하고자 하였다. <방법> 궤양성 대장염 환자 76명(남 37, 여 39), 크론병 환자 60명(남 41, 여 19)과 정상 대조군 203명(남 1129, 여 84)을 대상으로 혈액을 채취하였다. IL-10 유전자 촉진자의 일부인 ?082, -819,-592 및 +1

수용성 단백질로 활성화된 호중구에 대한 Rebamipide 의 효과

김주성(Joo Sung Kim),김정목(Jung Mogg Kim),김병관(Byeong Gwan Kim),김상균(Sang Gyun Kim),김지원(Ji Won Kim),김찬규(Chan Gyoo Kim),정현채(Hyun Chae Jung),송인성(In Sung Song) 대한소화기학회 2002 대한소화기학회지 Vol.39 No.1

Background/Aims: Helicobacter pylori (H. pylori) infection induces persistent neutrophil infiltration in gastric mucosa. The expression of cyclooxygenase (COX)-2 and inhibition of apoptosis in the neutrophils could contribute to the pathogenesis of H. pylori infection. Rebamipide, a mucosal protective and ulcer-healing drug, has been known to inhibit neutrophil activation. The aim of this study was to evaluate the effect of rebamipide on the neutrophils activated by Helicobacter pylori water-soluble proteins. Methods: After neutrophils were stimulated with H. pylori water extract (HPWE) or pretreated with rebamipide, the expression of COX-2 mRNA and protein was assessed by quantitative RT-PCR and Western blotting, respectively. Prostaglandin (PG) E2 synthesis was determined by radioimmunoassay. Neutrophil apoptosis was evaluated by cytosolic oligonucleosome-bound DNA ELISA and caspase-3 activity was measured by the detection of p-nitroanilide after cleavage from labeled substrate. Results: Stimulation with HPWE upregulated COX-2 expression and PGE2 secretion, and inhibited neutrophil apoptosis. Rebamipide suppressed PGE2 secretion from neutrophils in a dose-dependent manner. However, rebamipide did not affect neutrophil apoptosis and caspase-3 activity. Conclusions: Rebamipide effectively suppresses PGE2 secretion from neutrophils activated by H. pylori water-soluble proteins. This is another possible mechanism of gastric mucosal protection by rebamipide. (Korean J Gastroenterol 2002;39:13-21)

행정중심복합도시 추진에 따른 철도이용 활성화 방안

김병관(Byung Kwan Kim),오윤식(Yoon Sic Oh),김명수(Myung Soo Kim),김현구(Hyoun Ku Kim) 한국철도학회 2014 한국철도학회 학술발표대회논문집 Vol.2014 No.5

2012년 말부터 2014년까지 중앙행정기관 및 그 산하기관이 단계별로 이전함과 동시에 2030년까지 계획인구 50만명을 설정하여 행정중심복합도시 건설이 단계별로 추진되고 있다. 행정중심복합도시는 현재 국토의 중앙에 위치하고 있어 각 주요 거점 도시간의 통행을 처리하기 위해서 철도가 중심적인 역할을 수행하여야 할 것이라 판단된다. 이에 본 연구에서는 행정중심복합도시 추진계획에 따른 철도이용특성 변화, 철도연계계획, 철도운영 환경변화를 분석하고 주요 거점간의 통행에서 철도의 경쟁력 및 연계성을 분석하여 고속철도를 중심으로 오송역의 철도이용 활성화를 위한 방안을 검토하였다. From 2014 until the end of 2012, the central government and its agencies are expected to be transferred in the multifunctional administrative city. The multifunctional administrative city construction is being promoted step by step with planned population of 500,000 people. Multifunctional Administrative City is now located in the center of the country, and the railway would be expected to be central role of major mode to treat trips between each major city. Thus, this study analysis the characteristics of railway usages, railway linkup transportation plan and rail operation environment exchanges in accordance with the multifunctional administrative city promotion. Finally we analysis the competitiveness and connectivity of railway in terms of pass between each major city and consider strategies for increasing ridership of railway focusing of high-speed rail.