A Kinetic Study on the De-Crosslinking and Decomposition of Silane-Cross-Linked Polyethylene in Supercritical Methanol

Hong, Giyoung,Hong, Soon Man,Koo, Chong Min,Baek, Bum Ki,Lee, Hong-shik,Lee, Youn-Woo American Chemical Society 2015 INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH - Vol.54 No.48

<P>De-crosslinking of silane-cross-linked polyethylene (S-XLPE) in supercritical methanol was investigated. Changes in gel content and molecular weight with reaction temperature and reaction time were analyzed in a batch reactor, and kinetic parameters were calculated from the experimental data. The reaction time for de-crosslinking shortened as the reaction temperature increased and the complete de-crosslinking of S-XLPE was achieved at 320 °C and 20 min. The de-crosslinking rate of S-XLPE fit well with the first order reaction model. In addition, the molecular weight of de-cross-linked polyethylene (DXPE) decreased further as reaction temperature and reaction time increased when the reaction temperature exceeded 360 °C relative to that of the original polyethylene before being cross-linked. The decreasing molecular weight trend also fit well with the first order reaction model.</P>

수군 녹조류 (數群 綠藻類) 의 유리 아미노산 분포에 따른 계통학적 연구 조류의 화학성분과 계통학적 상관성에 대하여 (3)

이민재(Min Jai Lee),홍순우(Soon Woo Hong),이인규(In Kyu Lee) 한국식물학회 1962 Journal of Plant Biology Vol.5 No.3

LEE, Min-Jai, HONG, Soon-Woo & LEE, In-Kyu, (Dept. of Botany, Seoul National Univ.) An analytical studies of free amino acid and its relationship among the main groups of green algae (Ⅲ). Kor. Jour. Bot. V (3) : 25-29, 1962. Succeeding the previous papers, nineteen species of marine green algae and three species of fresh water green algae are analyzed to the free amino acid patterns by paper chromatogram, and it has been described as containing significant qualities of the pattern in relation to phylogenetic studies. Those seem to have a tendency of recognizable pattern on inter-Orders and inter-Phyla of marine algae. And the patterns of fresh water and marine green algae are also carried out referring to these studies.

Cytoprotective Effect of Hispidin Against Hyperglycemia Induced Oxidative Cell Damage on Mouse Insulin Producing Cells(MIN6)

Jae Soon Jang,Min Kyoung Min,Eock Kee Hong 한국생물공학회 2007 한국생물공학회 학술대회 Vol.2007 No.10

Endoscopic submucosal tunnel dissection salvage technique for ulcerative early gastric cancer.

Choi, Hyuk Soon,Chun, Hoon Jai,Seo, Min Ho,Kim, Eun Sun,Keum, Bora,Seo, Yeon Seok,Jeen, Yoon Tae,Lee, Hong Sik,Um, Soon Ho,Kim, Chang Duck,Ryu, Ho Sang WJG Press 2014 WORLD JOURNAL OF GASTROENTEROLOGY Vol.20 No.27

<P>Endoscopic submucosal dissection is an effective treatment modality for early gastric cancer (EGC), though the submucosal fibrosis found in ulcerative EGC is an obstacle for successful treatment. This report presents two cases of ulcerative EGC in two males, 73- and 80-year-old, with severe fibrosis. As endoscopic ultrasonography suggested that the EGCs had invaded the submucosal layer, the endoscopic submucosal tunnel dissection salvage technique was utilized for complete resection of the lesions. Although surgical gastrectomy was originally scheduled, the two patients had severe coronary heart disease, and surgeries were refused because of the risks associated with their heart conditions. The endoscopic submucosal tunnel dissection salvage technique procedures described in these cases were performed under conscious sedation, and were completed within 30 min. The complete en bloc resection of EGC using endoscopic submucosal tunnel dissection salvage technique was possible with a free resection margin, and no other complications were noted during the procedure. This is the first known report concerning the use of the endoscopic submucosal tunnel dissection salvage technique salvage technique for treatment of ulcerative EGC. We demonstrate that endoscopic submucosal tunnel dissection salvage technique it is a feasible method showing several advantages over endoscopic submucosal dissection for cases of EGC with fibrosis. (C) 2014 Baishideng Publishing Group Inc. All rights reserved.</P>

원인 불명의 실신 환자의 진단에 있어서 Head - up tilt Test 의 유용성과 혈관미주신경성 실신 환자의 임상적 특징

윤호중(Ho Joong Youn),정욱성(Wook Sung Chung),백상홍(Sang Hong Baek),김철민(Chul Min Kim),박인수(In Soo Park),김재형(Jae Hyung Kim),최규보(Kyu Bo Choi),홍순조(Soon Jo Hong) 대한내과학회 1994 대한내과학회지 Vol.47 No.2

N/A Background: Syncope, defined as a transient loss of consciousness, is a frequently encountered symptom, but despite thorough clinical and invasive diagnostic investigation, the cause of syncope remains unexplained. In recent years, head-up tilt test has been of increasing interest as a diagnostic aids in patients with unexplained syncope. We studied to define the usefulness of various diagnostic test in the evaluation of patients with recurrent syncope, to assess the usefulness of head-up tilt test in the working of syncope of unknown origin and to evaluate the clinical characteristics of subgroups of patients with syncope induced by head-up tilt test. Methods: Between June, 1991 and November, 1992 at St. Mary`s hospital, 21 patients with history of syncope and 24 control subjects without history of syncope underwent 60° head-up tild test for 60 min. Results: 1) The definite cause for recurrent syncope were diagnosed in 10 of patients (47,6%) after clinical and invasive tests. 2) During head-up tilt test, vasovagal responses were provoked in 5 of 21 patients (23.8%) with recurrent syncope and 1 of 24 patients (4.2%) without syncope (p<0,05). 3) The head-up tilt test induced symptomatic bradycardia or hypotension in 3 of 10 patients (30%.) with negative electrophysiologic results. 4) During tilt induced vasovagal response, a) mean heart rate decreased to 42±24 beat/min from supine control of 70±12 beat/min (p<0. 05), b) mean systolic blood pressure decreased to 95±12 mmHg from supine control of 120±S mmHg (p<0,05), c) mean diastolic blood pressure decreased to 60±21mmHg from supine control of 72±13 mmHg (p<0.05), d) the time interval to onset of vasovagal response was 22±12 min. Conclusions: 1) In a large proportion of patients with recurrent syncope, the diagnosis remains unexplained despite a neurologic and cardiologic investigation including an electrophysiologic study. 2) Vasovagal responses are frequent cause in patients with recurrent unexplained syncope. 3) The head-up tilt test may be a simple, safe and highly yielding provocative test in the investigation of syncope of unknown origin.

밀링 에너지 변화에 따른 TiC 분말의 미세화 거동에 관한 정량적 연구

홍성모,박은광,김경열,박진주,이민구,이창규,이진규,권영순,Hong, Sung-Mo,Park, Eun-Kwang,Kim, Kyeong-Yeol,Park, Jin-Ju,Lee, Min-Ku,Rhee, Chang-Kyu,Lee, Jin-Kyu,Kwon, Young-Soon 한국분말야금학회 2012 한국분말재료학회지 (KPMI) Vol.19 No.1

This study investigated refinement behaviors of TiC powders produced under different impact energy conditions using a mechanical milling process. The initial coarse TiC powders with an average diameter of 9.3 ${\mu}m$ were milled for 5, 20, 60 and 120 mins through the conventional low energy mechanical milling (LEMM, 22G) and specially designed high energy mechanical milling (HEMM, 65G). TiC powders with angular shape became spherical one and their sizes decreased as the milling time increased, irrespective of milling energy. Based upon the FE-SEM and BET results of milled powders, it was found initial coarse TiC powders readily became much finer near 100 nm within 60 min under HEMM, while their sizes were over 200 nm under LEMM, despite the long milling time of up to 120 min. Particularly, ultra-fine TiC powders with an average diameter of 77 nm were fabricated within 60 min in the presence of toluene under HEMM.

The effects of secondary task on the control of vehicle under driving simulator: a study among 50s taxi drivers

Han Soo Kim,Jin Seung Choi,Dong Won Kang,Hong Won Yeon,Mi Hyun Choi,Doo Hwan Ji,Byung Chan Min,Soon Cheol Chung,Gye Rae Tack 대한인간공학회 2011 대한인간공학회 학술대회논문집 Vol.2011 No.5

Objective: The aim of this study is to quantitatively evaluate the effects of the secondary task during simulated driving using the variable indicating control of vehicle. Background: There are so many researches for simulated driving and performance. For instance, some researches show that the effects of cell phone conversations on simulated driving. Cell phone conversations impaired explicit recognition memory. Method: Participants included 50s taxi drivers; 15 males and 15 females. All subjects were instructed to keep a distance (30m) from the car ahead and a constant speed (80km/hr or 100km/hr). Sending text message (STM) and Searching navigation (SN) were selected as the secondary task. Experiment consisted of rest for 3min., driving alone for 1min. and driving with secondary task for 1 min.. We were analyzed anterior-posterior coefficient of variation (APCV) and medial-lateral coefficient of variation (MLCV). Results: APCV was increased by 175.4% in STM and 223.8% in SN at 80km/hr. MLCV was increased by 242.3% in STM and 323.4% in SN at 100km/hr. There was no significant difference between genders. Conclusion: Consequently, performing secondary task during driving impaired the control of vehicle.

C -11 및 F - 18 표지 콜린의 합성과 체내동태에 관한 연구

전권수,유국현,김상욱,임상무,홍성운,서용섭,양승대,안순혁,허민구 대한핵의학회 2001 핵의학 분자영상 Vol.35 No.3

Objectives: Recently, [methyl-(11)^C]-(β-Hydroxyethyl)trimethylammonium ([(11)^C]choline) has been discovered to be a very effective tracer in imaging various human tumors using positron emission tomography. Because of the short half-life of C-11, it is very difficult to use in a routine imaging procedure and needs a frequent synthesis of [(11)^]choline. This can be supplemented by the substitution of [(11)^Ccholine with [methyS-18]fluorocholine. Here, we would like to report cell uptake and biodistribution of [(11)^Ccholine and [(18)^F]fluorocholine as a basic study. Methods [(11)^C]Choline was prepared by the treatment of [(11)^C]CHzI with N,N-dimethylaminoethanol and [18F]fluorocholine was synthesized from reaction of CHzBr[18F]F with N,N-dimethylaminoethanol. The radiochemical purity was checked by high performance liquid chromatography (HPLC). The biodistribution of [(11)^C]choline and [(18)^F]fluorocholine was determined in balb/c mouse at 5 min, 20 min, 40 min and 80 min. The cell uptake wa measured using glioma (9L) and colon adeocarcinoma (SW620). Results: The radiochemical purity was more than 98% after purification. In the liver, uptake did not change over time the uptake was 20/ID/g for [C]choline and 13%ID/g for [(18)^F]fluorocholine. In the kidney, radioactivity decreased over tirne the uptake was 15%1D/g for [(11)^Ccholine and 20%ID/g for [(18)^F]fluorocholine, 80 min post-injection. The cell uptake of [(11)^Ccholine was 4.93% for glioma (9L) and 18.69F for colon adenocarcinoma (SW620). For [(18)^F]fluorocholine, 1.77% for glioma (9L) and 2.77% for colon adenocarcinoma (SW620). Conclusion: [(11)^CCholine and [(18)^F]fluorocholine showed a different cell uptake tendency, depending on cancer cell line. (Korean J Nucl Med 200135:185-191)

Sn-3.5Ag 솔더 범프 플립칩의 무플럭스 열초음파 접합

洪淳珉,姜春植,鄭在弼 대한금속재료학회 2002 대한금속·재료학회지 Vol.40 No.6

The thermosonic bonding was investigated as a fluxless solder bump flip chip bonding method. The 100 ㎛-diameter Sn-3.5 mass%Ag solder bumps were formed on test flip chip by laser ball bonding process. The test flip chips were bonded to a TSM-coated glass substrate using thermosonic bonding method at different temperature, bonding load and ultrasonic power. The die shear strength was evaluated and fracture surfaces were examined with SEM. The Sn-3.5Ag solder flip chip bonding was possible at lower temperature than the melting point of the solder. The die shear strength increased with increasing bonding temperature, bonding load, and ultrasonic power. However, at excessive bonding load condition over 1.0 N/bump, the die shear strength decreased due to the fracture at UBM/ Si-chip interface. The bump height decreased with increasing bonding load but did not change with ultrasonic power.

톱밥 畜産糞尿 醱酵堆肥 種類가 배추 收量에 미치는 影響

閔庚範,洪淳達 충북대학교 농업과학기술연구소 1996 農業科學硏究 Vol.13 No.-

This study was conducted to evaluate the effect of different fermented manure- sawdust composts(FMSC) application on Chinese cabbage growth in the field. Chinese cabbage was cultivated in sandy loam applied with 30t/ha of fermented pig manure-sawdust compost(FPMSC), fermented fowl manure-sawdust compost(FFMSC), fermented cattle manure-sawdust compostFCMSC) respectively, and control. The results obtained were as follows ; 1. FMSC treatments increased the Chinese cabbage yield by 31-41% while the decrease of N 120㎏/ha, P 100㎏/ha fertilizers compared to control. Effects of three FMSC on yield of Chinese cabbage were in the order of FPMSC>FFMSC>FCMSC. 2. Soil bulk density and hardness were decreased while OM, T-N, Mg, K in the soil were increased by FMSC after harvest. 3. Compare to three FMSC control or control+compost plot at 30day after transplanting soil NH4-N content was increased but at 60days after transplanting NH4-N content wasn't increased, and at harvest NH4-N content was decreased. Soil NO3-N content was increased from early growth to yield of Chinese cabbage. 4. Inorganic element absorption on 12th of November was increased by three FMSC. FPMSC treatment increased T-N absorption and FPMSC, FCMSC increased P2O5 absorption in Chinese cabbage more compared to different FMSC. Key words : Compost, Fermented Manure, Sawdust, Chinese cabbage.