Study of the Optimal Calcination Temperature of an Al/Co/Ni Mixed Metal Oxide as a DeNO<SUB>x</SUB> Catalyst for LNT

Kil Nam Jang,Kwang Seon Han,Ji Sook Hong,Young-Woo You,Jeong Kwon Suh,Taek Sung Hwang 한국청정기술학회 2015 청정기술 Vol.21 No.3

대부분의 LNT 촉매는 낮은 온도 영역에서의 NOx 산화를 위하여 Pt와 같은 귀금속류를 사용하는 것은 경제적인 부담을 가지고 있다. 따라서, 본 연구는 이러한 문제를 해결하기 위하여 시도되었다. 즉, Pt, Pd, Rh 등과 같은 귀금속류(platinum group metal, PGM)를 사용하지 않는 LNT (lean NOx trap)용 DeNOx 촉매를 개발하기 위해 시도하였다. 이를 위해서 예비실험을 통해 Pt등 귀금속류등의 PGM (platinum group metal)을 사용하지 않는 Al/Co/Ni 혼합 금속 산화물을 선정하였다. 궁극적으로는, 선정된 촉매의 소성온도에 따른 물리화학적 특성 변화가 NOx 전환율에 미치는 영향을 살펴보고자 하였다. 이들의 물리화학적인 성질을 평가하기 위해 XRD, EDS, SEM, BET 분석을 실시하였다. 이러한 평가를 실시한 결과, 모든 소성온도에서 혼합금속 산화물은 Co₂AlO₄ 및 NiAl₂O₄의 스피넬 구조가 혼재되어 있는 것으로 나타났고, NOx 기체들의 산화-환원 반응이 이루어지기에는 충분한 기공부피와 기공크기를 갖고 있음을 알 수 있었다. 그러나 NH₃-TPD 분석 결과에서는 소성온도가 700 ℃ 이하를 유지해야 하는 것으로 판단되었다. 더욱이 ramp test를 통해서는 NO 및 NOx 전환율을 동시에 만족할 수 있는 시료는 소성온도는 500 ℃에서 처리된 경우임을 알 수 있었다. 이러한 결과 등을 바탕으로, Al/Co/Ni=1.0/2.5/0.3 혼합 금속산화물의 최적 소성온도는 500 ℃임을 알 수 있었다. Most of LNT catalysts use noble metals such as Pt for low temperature NOx oxidation but there is an economic weakness. For the purpose of overcoming this, this study is to develop DeNOx catalyst for LNT excluding PGM (platinum group metal) such as Pt, Pd, Rh, etc. To do so, Al/Co/Ni catalyst selected as a preliminary test is used to study fundamental property and NOx’s conversion according to calcined temperature. Ultimately, that is, Al/Co/Ni mixed metal oxide which does not use PGM is selected and physicochemical characterization is performed by way of XRD, EDS, SEM, BET and ramp test and NOx conversion is also analyzed. This study shows that all samples consist of mixed oxides of spinel structure of Co₂AlO₄ and NiAl₂O₄ and have enough pore volume and size for redox. But as a result of NH3-TPD test, it is desired that calcined temperature needs to be maintained at 700 ℃ or lower. Also only samples which are processed under 500 ℃ satisfied NO and NOx conversion simultaneously through ramp test. Based on this study’s results, optimum calcined temperature for Al/Co/Ni=1.0/2.5/0.3 mixed metal oxide catalyst is 500 ℃.

Genotypic Variation of Helicobacter pylori Isolated from Gastric Antrum and Body in Korean Patients

Seon Mee Park,Soon Kil Kwon,Bo Ra Son,Kyeong Seob Shin,Chan Won Woo,Eung-Gook Kim,Seok-Yong Kim 大韓微生物學會 2000 大韓微生物學會誌 Vol.35 No.1

이동 맹장을 가지는 장의 회전이상 1례

권순길,박선미,윤세진,채희복,배일헌,정현용 충남대학교 의과대학 지역사회의학연구소 2001 충남의대잡지 Vol.28 No.1

Intestinal malrotation is an uncommon congenital anomaly in adults that is caused by the disturbance of normal intestinal rotation processes during fetal development. It can be found in infant or childhood but can remain asymptomatically until adult. Among the many different type of intestinal malrotation, the mobile cecum is more common than others. We experienced a case of intestinal malrotation with mobile cecum in a 63-year-old female who had been suffered from abrupt onset of low abdominal pain. The diagnosis of intestinal malrotation was made by barium enema and abdominal CT and mobile cecum was made by small bowel series. Patient remained asymptomatic after conservative management.

Study of the Optimal Calcination Temperature of an Al/Co/Ni Mixed Metal Oxide as a DeNO_x Catalyst for LNT

Jang, Kil Nam,Han, Kwang Seon,Hong, Ji Sook,You, Young-Woo,Suh, Jeong Kwon,Hwang, Taek Sung The Korean Society of Clean Technology 2015 청정기술 Vol.21 No.3

대부분의 LNT 촉매는 낮은 온도 영역에서의 NO_x 산화를 위하여 Pt와 같은 귀금속류를 사용하는 것은 경제적인 부담을 가지고 있다. 따라서, 본 연구는 이러한 문제를 해결하기 위하여 시도되었다. 즉, Pt, Pd, Rh 등과 같은 귀금속류(platinum group metal, PGM)를 사용하지 않는 LNT (lean NO_x trap)용 DeNO_x 촉매를 개발하기 위해 시도하였다. 이를 위해서 예비실험을 통해 Pt등 귀금속류등의 PGM (platinum group metal)을 사용하지 않는 Al/Co/Ni 혼합 금속 산화물을 선정하였다. 궁극적으로는, 선정된 촉매의 소성온도에 따른 물리화학적 특성 변화가 NO_x 전환율에 미치는 영향을 살펴보고자 하였다. 이들의 물리화학적인 성질을 평가하기 위해 XRD, EDS, SEM, BET 분석을 실시하였다. 이러한 평가를 실시한 결과, 모든 소성온도에서 혼합금속 산화물은 Co₂AlO₄ 및 NiAl₂O₄의 스피넬 구조가 혼재되어 있는 것으로 나타났고, NO_x 기체들의 산화-환원 반응이 이루어지기에는 충분한 기공부피와 기공크기를 갖고 있음을 알 수 있었다. 그러나 NH₃-TPD 분석 결과에서는 소성온도가 700 ℃ 이하를 유지해야 하는 것으로 판단되었다. 더욱이 ramp test를 통해서는 NO 및 NO_x 전환율을 동시에 만족할 수 있는 시료는 소성온도는 500 ℃에서 처리된 경우임을 알 수 있었다. 이러한 결과 등을 바탕으로, Al/Co/Ni=1.0/2.5/0.3 혼합 금속 산화물의 최적 소성온도는 500 ℃임을 알 수 있었다. Most of LNT catalysts use noble metals such as Pt for low temperature NO_x oxidation but there is an economic weakness. For the purpose of overcoming this, this study is to develop DeNO_x catalyst for LNT excluding PGM (platinum group metal) such as Pt, Pd, Rh, etc. To do so, Al/Co/Ni catalyst selected as a preliminary test is used to study fundamental property and NO_x’s conversion according to calcined temperature. Ultimately, that is, Al/Co/Ni mixed metal oxide which does not use PGM is selected and physicochemical characterization is performed by way of XRD, EDS, SEM, BET and ramp test and NO_x conversion is also analyzed. This study shows that all samples consist of mixed oxides of spinel structure of Co₂AlO₄ and NiAl₂O₄ and have enough pore volume and size for redox. But as a result of NH₃-TPD test, it is desired that calcined temperature needs to be maintained at 700 ℃ or lower. Also only samples which are processed under 500 ℃ satisfied NO and NO_x conversion simultaneously through ramp test. Based on this study’s results, optimum calcined temperature for Al/Co/Ni=1.0/2.5/0.3 mixed metal oxide catalyst is 500 ℃.

Identification and Management of Sulfonylurea-resistant Biotype of Scirpus planiculmis in Reclaimed Paddy Fields, Korea

Tae-Seon Park(박태선),Chung-Kil Kang(강충길),Jae-Eup Park(박재읍),Bon-Il Ku(구본일),Hong-Kyu Park(박홍규),Sita Ram Ghimire(기미어 시다람),Young-Doo Kim(김영두),Jae-Kwon Ko(고재권) 韓國雜草學會 2009 Weed&Turfgrass Science Vol.29 No.2

Sulfonylurea(SU)계 제초제에 대한 저항성 새섬매자기가 한국의 서산 간척지 논에서 발생한 것이 확인되었다. SU 제초제 저항성 새섬매자가 발생한 논은 1990년부터 13년 동안 연속적으로 SU계 혼합 제초제를 사용하였다. 온실 조건에서 서산과 무안에서 채취한 새섬매자기 구경을 이식 후 10일에 azimsulfuron, bensulfuron-methyl, cinosulfuron, ethoxysulfuron, imazosulfuron 그리고 pyrazosulfuron-ethyl을 처리하였을 때 무안의 새섬매자기는 각 제초제 추천량에서 방제가 되었으나 서산의 새섬매자기는 추천량의 5배량에서도 20-40% 생존되었다. 생체중 50%를 억제하는 각 제초제의 농도(GR50)는 두 지역에서 채취한 새섬매자기 간에 현저한 차이가 있었으며, 서산의 매자기에 대한 6 종류의 GR50은 무안의 새섬매자기 대한 GR50값 보다 47-100배 높게 나타났다. 또한 무안과 서산의 새섬매자기에서 추출한 acetolactate synthase(ALS)에 대한 pyrazosulfuron-ethyl의 50% 억제 농도(I50)각각 0.8 nM과 409 nM로 나타나, 서산의 새섬매자기가 무안의 새섬매자기 보다 511배 높은 저항성을 가지고 있음을 확인하였다. SU계 제초제 저항성 새섬매자기를 효과적으로 방제하기 위한 제초제 선발 결과 benzobicyclone이 효과적이었다. 간척지 담수직파논에서는 파종 전에 이행성 비선택성 제초제인 glyphosate SL를 처리한 다음, 파종 후 10일에 benzobicyclone+azimsufuron+metamifop GR를 처리하는 것이 매우 효과적이었다. A suspected biotype of Scripus planiculmis to be resistant to sulfonylurea (SU) herbicides was identified in Seosan reclaimed paddy fields in Korea. The fields have been cultivated for monocultural rice production with wet-direct seeding method and continuously treated with SU-based herbicide mixtures for thirteen years since 1990. In greenhouse studies, 6 different SU herbicides, such as azimsulfuron, bensulfuron-methyl, cinosulfuron, ethoxysulfuron imazosulfuron and pyrazosulfuron-ethyl, completely controlled the Muan assession of S. planiculmis at the recommended dose rate of each herbicide, however, the Seosan accession of S. planiculmis biotype was survived 20 to 45% even treated with 5 times higher dose of each recommended rate of all herbicides treated. The GR50 values of 6 SU herbicides for Seosan accession of S. planiculmis were 47 to 100 times higher than those for Muan accession of S. planiculmis. The I50 values pyrazosulfuron-ethyl to acetolactate synthase (ALS) extracted from Sean and Muan accession of S. planiculmis were 409 nM and 0.8 nM, respectively. The I50 value of Seosan was 511 times higher than that of Muan accession. These results suggested that the Seosan accession of S. planiculmis have strong resistant characteristics to 6 SU herbicides, respectively, indicating that resistance might be due to the alteration in the target site of ALS. In the pot experiment, benzobicyclon having different mechanisms of action from SU herbicides had excellent controlling effects on the resistant biotype when their plant height were applied below 5 cm. The management in reclaimed paddy fields was very effective under the treatment of systematic herbicides such as foliar applied glyphosate SL at 15 days before seeding followed by benzobicyclon-included herbicides at 10 days after seeding.

Isolation and Identification Putrescine and Tryptamine Producing Bacteria from Commercial Sand Lance, Ammodytes personatus, Sauces

In-Seon Eom,Tae-Ok Kim,Jung-Kil Seo,Seung-Yong Lim,Na-Young Lee,Yong-Tae Kim,Kwon-Sam Park 한국수산과학회 양식분과 2016 한국수산과학회 양식분과 학술대회 Vol.2016 No.10

Isolation and Identification Putrescine and Tryptamine Producing Bacteria from Commercial Sand Lance, Ammodytes personatus, Sauces.

In-Seon Eom,Tae-Ok Kim,Jung-Kil Seo,Seung-Yong Lim,Na-Young Lee,Yong-Tae Kim,Kwon-Sam Park 한국수산해양기술학회(구 한국어업기술학회) 2016 한국수산해양기술학회 학술발표대회 Vol.2016 No.10

공기부양선의 추진 및 부양축계 횡진동 해석에 관한 연구

손선태(Seon-Tae Son),길병래(Byung-Lea Kil),조권회(Kwon-Hae Cho),김정렬(Jung-Ryul Kim) 한국마린엔지니어링학회 2008 한국마린엔지니어링학회지 Vol.32 No.2

Is Cholecystectomy Necessary After ERCP for Bile Duct Stones in Patients with Gallbladder in situ ?

(Soon Kil Kwon),(Byung Seok Lee),(Nam Jae Kim),(Heon Young Lee),(Hee Bok Chae),(Sei Jin Youn),(Seon Mee Park) 대한내과학회 2001 The Korean Journal of Internal Medicine Vol.16 No.4

N/A Background: The requirement for subsequent cholecystectomy in patients with gallbladder in situ after endoscopic removal of stones from the common bile duct (CBD) is controversial. The aims of this study were to assess the requirement for subsequent cholecystectomy for gallbladder-related symptoms, and to identify the patients who develop symptoms after the endoscopic removal of CBD stones. Methods: Of 241 patients with gallbladder in situ following endoscopic removal of stones from the CBD, 146 patients (78 men and 68 women; mean age 69±13 years, range 20-93) with a follow-up time of more than three months without elective cholecystectomy were enrolled in the study. Fifty-nine patients had gallbladder stones (single stones in 27 and multiple stones in 32) and 87 patients had gallbladder in situ without stones. The time from entry to the occurrences of death or cholecystectomy was evaluated retrospectively. Cox regression analysis was used to evaluate the risk factors associated with these events. Results: The mean duration of follow-up was 24.1±18.0 months (range 3-70 months). During follow-up, seven patients (4.8%) underwent cholecystectomy, on average 18.4 months after CBD stone removal, as the result of acute cholecystitis in four cases, biliary pain in two cases and acute pancreatitis in one case. Laparoscopic cholecystectomy was performed in four patients and open cholecystectomy in three patients. Post-operative morbidity occurred in two patients, with improvement after conservative management. Nine patients (6.2%) died as the result of unrelated biliary disease. Age, sex, presence of gallbladder stones, multiplicity of gallbladder stones and underlying disease did not correlate with subsequent cholecystectomy by Cox regression analysis. Conclusion: Elective cholecystectomy is not warranted in patients with bile duct stones when the common duct can be cleared of stones by endoscopic sphincterotomy. We could not find any clinical predictors of further symptoms or complications arising from the retained gallbladder.

Differential Herbicide Response of Sulfonylurea-Resistant Scirpus juncoides Roxb. Accessions to Sulfonylurea Herbicides

Tae-Seon Park(박태선),Hong-Kyu Park(박홍규),In-Yong Lee(이인용),Byung-Chul Moon(문병철),Bon-Il Ku(구본일),Chung-Kil Kang(강충길),Young-Doo Kim(김영두),Jae-Kwon Ko(고재권) 韓國雜草學會 2009 Weed&Turfgrass Science Vol.29 No.3

국내 4개 지역의 수집종간 sulfonylurea(SU)계 제초제 저항성을 올챙이고랭이의 저항성 정도 차이를 구명하기 위하여 SU계 제초제들에 대한 식물체 및 acetolactate synthase(ALS) 반응 차이를 감수성 계통과 비교 분석하였다. 김제, 나주 지역에서 채집된 저항성 올챙이고랭들은 SU계 제초제들의 기준량에서 거의 생육에 영향을 받지 않았다. 사용된 SU계 제초체들의 기준량에 대한 김제와 나주지역계통의 생체중은 각각 95~109% 및 90~98%를 보였다. 그란 김해 채집계통의 처리된 설포닐우레아계 제초제들의 기준량에 대한 생체중은 무처리 대비 41~58% 나타내어 중간정도의 저항성을 보였다. 김제와 나주 채집종에 대한 ALS 50% 억제 제초제 농도인 I50은 감수성 채집계통에 비해 각각 283~1,074배 및 157~870배 높게 나타났다. 그러나 서산 채집계통의 I50은 감수성인 수언 채집계통에 비해 5~11배 높게 나타났다. 설포닐우레아계 제초제 저항성 올챙이고랭이에 대한 비설포닝우레아계통 제초제들 중 13종류의 제초제를 시험한 결과 벤조비싸이크론과 부로모부타이드 입제가 매우 효과적이었다. Three sulfonylurea (SU)-resistant Scirpus juncoides Roxb. accessions were tested for levels of resistance to four SU herbicides which have been widely using in paddy fields of Korea since 1990, based on whole plant response and sensitivity of the target enzyme, acetolactate synthase (ALS). Gimje and Naju accessions were not affected to the survival by treatment with recommended doses of all SU herbicides tested. The fresh weight of Gimje and Naju accessions were 95% (ethoxysulfuron) to 109% (bensulfuron-methyl) and 90% (ethoxysulfuron) to 98% (imazosulfuron) to the recommended doses of all SU herbicides tested than the susceptible Suwon accession, respectively. However, the fresh weight for Seosan accession displayed an intermediate response and was only 41% (ethoxysulfuron) to 58% (imazosulfuron) more resistant than the susceptible accession. I50 values the ALS for the Gimje and Naju accessions were 283 (parzosulfuron ethyl)- to 1,074 (bebsulfuron-mthyl)-fold and 157 (bensulfuron-methyl)- to 870 (prazosulfuron-ethyl)-fold higher to the recommended doses of all SU herbicides tested than the susceptible Suwon accession, respectively. However, the I50 value for Seosan accession was 4- to 9-fold more resistant than the susceptible accession, as determined by I50 values of ALS. Benzobicyclone SC and bromobutide GR of alternative herbicides tested showed the very high efficacy to S. juncoides seedlings without rice injury.