TiO₂/UV공정을 이용한 수중 MTBE의 광분해 특성

류성필,김성수,오윤근 한국환경과학회 2004 한국환경과학회지 Vol.13 No.3

The objective of this study is to delineate removal efficiency of the MTBE in solution by TiO₂ photocatalytic degradation as a function of the following different experimental conditions : Initial concentration of MTBE, air flow rate in solution, H₂O₂ dosage and pH of the solution. Photodegradation rate was increased with decreasing initial concentration of MTBE. The removal efficiency was 82% after 180 min in the case of MTBE concentration of 100 mg/L but 100% after 180 min in the case of 20 mg/L. Removal efficiency was increased with increasing pH, H₂O₂ dosage and air flow rate in solution.

서산지역 굴피나무(Platycarya strobilacea)군락의 동태

류영수,허혜경,김성덕,박경배 忠南大學校 環境問題硏究所 1997 環境硏究 Vol.15 No.-

The regeneration process and the composition of species of climax Platycarya strovilacea S. et Z. forest was studied in Mujang-Ri, Jigok-Myon, Sosan, Chungchungnam-Do Province. Total number of vascular plant species of this community was recorded 125. This results seem to be related to various soil and light conditions in this community. The dominant trees of the stands came up beyond 12m in height. The upper tree layer is highly dominated by Platycarya strovilacea, which have more than two stems, is over 15cm in DBH class and is like stumps. They were distributed horizontally in random. Trees of the middle and lower layer were few in number and small in basal area. It tended to be distributed contagiously, in the age distribution of trees, some of the even-aged cluster which were constituted of several trees, were found in plot. The growth rates of the stem diameter for the first 20 years of the trees in upper layer were higher than those of the same species in the middle layer. These results show that the seedings which were established in dense grows with the decreasing density after the forest canopy had been broken out , and distribution pattern became in random, would constitute the canopy developing the community level.

CRM 아스팔트의 친환경적 특성

유병로,박성의,한양수 大田産業大學校 2000 한밭대학교 논문집 Vol.17 No.1

Improvement of environmental friendly characteristics on asphalt pavement is one of the important processes to make good quality asphalt. The asphalt mixture with CRM (Crumb Rubber Modifier) is known to show a better performance in penetration, noise reduction, physical characteristics including resisting thermal cracking, fatigue cracking and rutting compared with the conventional mixture. In this study, the test on the environmental friendly characteristics, physical and mechanical characteristics of the domestic crumb rubber modified asphalt and conventional asphalt(AP-5) were conducted. The test results show that CRM asphalt has better physical and mechanical characteristics including indirect tensile strength and stiffness modules than that of conventional asphalt. The results from the test of environmental characteristics can be summarized by the followings. The optimum asphalt content of CRM mixture by Marshall test showed the range from 5% to 5.8%. The penetration ability of CRM asphalt has about a hundred times higher than conventional asphalt. CRM asphalt was considered to improve the environmental characteristics on asphalt pavement.

제통단이 퇴행성 슬관절염 환자의 삶의 질에 미치는 영향

서병관,류성룡,강중원,우현수,이상훈,이재동,최도영,김건식,이두익,이윤호 EAST-WEST MEDICAL RESEARCH INSTITUTE KYUNG HEE UNI 2005 東西醫學硏究所 論文集 Vol.2005 No.-

Objectives : to evaluate the effects of Jetongdan, the newly developed herbal medicine, on the quality of life in patients with osteoarthritis of knee Methods : Placebo-controlled, randomized clinical trial on the 80 patients with osteoarthritis of the knee was fulfilled. After enrollment, they took medication as they enrolled. And they were asked to answer the questionnaires (Korean Health Assessment Questionnaire (KHAQ), Lequesne's functional index (LF1), visual analogue scale (VAS)) and analysed with the erythrocyte sedimentation rate (ESR) at baseline, after 4 weeks and 8 weeks of medication. Results : Total KHAQ score, some categories of KHAQ like hygiene, activities were significantly improved after 8 weeks of medication. And the change of the KHAQ score was significantly correlated with the change of VAS. But LFI, VAS, ESR level was not significantly improved, and it was considered because of the short medication period and small size of study population. Conclusion : In conclusion, Jetongdan could improve the health-related quality of life in patients with osteoarthritis of knee. Further study in the large population, in long period were recommended.

돈분뇨의 토양처리시 이온 성분의 용탈 특성

김태헌,류성필,김성수,오윤근,허철구 한국환경과학회 2003 한국환경과학회지 Vol.12 No.3

An agricultural land application of swine slurry is one of the best management practices in Jeju island whose ground water must be protected. So as to study the effect of appling swine slurry on ground water or aquifer, incubation-leaching technique was used by assuming the incubating period of 1, 2, 4, 8, 16, or 32 days, and application rate of 3200.0㎎T-P/ℓ, 820.0㎎T-P/ℓ, and 1887.0㎎K^+/ℓ in swine slurry. The leachates were collected from the soil columns(PVC 30㎝L×5.5㎝D) packed 15㎝ in depth with Gangjeong soil series by washing with 100mL distilled water. The leached components were measured by using Ion chromatography for Cl^-, NO_3-N, F^-,Br^-, Na^+, K^+, Ca^2+, and Mg^2+, atomic absorption spectrophotometry for Fe and Mn, and UV-Vis spectrophotometry for T-N and T-P. Application of swine slurry in naked soil could influence on the ground water or aquifer by increasing nitrate-nitrogen in leachate with time, or leaching the cations present in soils in accompany with anions because of H^+ produced in nitrification. Therefore, careful consideration should be taken about what amount, when, where, and how for protecting ground water system.

병원획득 Klebsiella pneumoniae 균혈증 분석을 통해 본 Ciprofloxacin 내성과 Extended-Spectrum β-Lactamase생성 간의 연관성

김미영,추은주,곽이경,송문희,나성수,송태준,김성혜,전재범,최상호,정진용,김남중,김양수,우준희,류지소 대한감염학회 2004 감염과 화학요법 Vol.36 No.5

목적 : K. pneumoniae는 ciprofloxacin내성 증가가 전세계적으로 문제가 되고있는 extended-spectrum beta-lactamase (ESBL)를 생성하는 대표적인 세균으로 최근 외국에서 ciprofloxacin 내성과 ESBL 생성사이에 관련이 있다는 2-3편의 보고들이 있었다. 본 연구에서는 병원획득 K. pneumoniae 패혈증이 있었던 환자들을 대상으로 ciprofloxacin 내성과 관련된 인자를 알아보고자 하였다. 재료 및 방법 : 2001년 1월 부터 2002년 12월 사이에 2200병상의 3차 의료기관인 한 대학병원에서 입원 후 72시간 이후에 나간 혈액배양에서 K. pneumoniae가 배양된 입원환자를 대상으로 의무기록과 전산기록을 분석하여 환자의 성별, 나이, 병동, 기저질환, 이전의 항생제 사용력, 패혈증 발생당시까지의 재원기간, 이전 입원력, 원인균의ESBL 생성유무 등을 파악하였고 이들 변수가 ciprofloxacin 내성과 관련이 있는지를 분석하였다. 재발성 패혈증의 경우는 첫 번째 경우만을 분석에 포함하였다. 결과 : 연구대상 환자는 총154명이었고 K. pneumoniae의 ciprofloxacin에 대한 내성률은 28.6% (44/154)였다. Ciprofloxacin 내성균주 중 ESBL 생성균주의 비율은 95.5% (42/44)였고 ciprofloxacin 감수성균주에서 ESBL 생성균주의 비율은 24.5% (27/110)였다(P<0.001). ESBL생성외에 단변량 분석에서 유의한 관련을 보인 변수로는 남자, 나이가 많은 경우, 패혈증 당시 중환자실 재원, 기저질환이 고형암, 혈액암, 담도계 질환인 경우, 패혈증 발생이전 1달 이내의 항생제 사용력, 3세대 cephalosporin, metronidazole, fluroquinolone, carbapenem 투여력이 있었다. 다변량 로지스틱 분석을 시행 하였을 때는 나이가 많은 경우(Adjusted odds ratio[A0R]; 1.04, 95%confidence interval[CI]; 1.01-1.06)와 ESBL 생성(AOR; 81.35, 95% CI; 17.76-372.53)이 유의하게 ciprofloxacin 내성과 관련이 있었다. 결론 : 패혈증을 일으킨 병원획득 K. pneumonias에서의 ciprofloxacin 내성은 ESBL 생성과 유의한 관련을 보였고 향후 이에 관련된 원인이나 기전을 분석하기위한 분자역학적·분자생물학적 연구가 필요하겠다. Background : Strains of ciprofloxacin-resistant Klebsiella pneumoniae have emerged worldwide. We investigated the epidemiology of ciprofloxacin resistance and its relationship to ESBL production in nosocomial K. pneumoniae bacteremia. Materials and Methods : Using the computerized database of clinical microbiology, we identified all patients whose blood culture had yielded K. pneumoniae between January 2001 and December 2002 at a 2200-bed university-affiliated tertiary-care hospital. During the study period, total of 392 episodes of K. pneumoniae bacteremia were documented of which 163 episodes were acquired nosocomially. 9 cases of recurrent episodes were excluded. Results : The resistance rates to ciprofloxacin was 28.6% (44/154). ESBL-production was significantly more common in ciprofloxacin-resistant isolates than in ciprofloxacin-susceptible isolates (95.9% [42/44] vs. 24.5% [27/110], P<0.001). In univariate analysis, following factors were significantly associated with resistance to ciprofloxacin: older age, male sex, ICU admission at the time of bacteremia, prior use of antibiotics within 1 month before bacteremia, solid tumor, hematological malignancy, or biliary disease as underlying disease, and ESBL-production. The prior use of 3^(rd)-generation cephalosprins, metronidazole, fluroquinolone, or carbapenem were also risk factors. Independent risk factors for ciprofloxacin resistance were older age (adjusted odds ratio [AOR]; 1.04, 95% confidence interval [CI]; 1.01-1.06) and ESBL production (AOR; 81.35, 95% CI; 17.76-372.53). Conclusion : The close relationship between ciprofloxacin resistance and ESBL production was documented in nosocomial K. pneumoniae bacteremia. Further epidemiological and molecular studies to determine factors and mechanisms involved in the relationship are needed.

Isolation of Biogenic Amine Non-producing Lactobacillus brevis SBB07 from Blueberry and Its Potential Probiotic Properties

Su-Ji Jeong,Hee-Jong Yang,Seong-Yeop Jeong,Myeong Seon Ryu,Gwang Su Ha,Jin Won Kim,Su Jin Shin,Hoyeon Yang,Ji Won Seo,Su A Im,Do-Youn Jeong 한국식품영양과학회 2017 한국식품영양과학회 학술대회발표집 Vol.2016 No.10

Synthesis and Electrochemical Characterization of Silica-Manganese Oxide with a Core-shell Structure and Various Oxidation States

Ryu, Seong-Hyeon,Hwang, Seung-Gi,Yun, Su-Ryeon,Cho, Kwon-Koo,Kim, Ki-Won,Ryu, Kwang-Sun Korean Chemical Society 2011 Bulletin of the Korean Chemical Society Vol.32 No.8

Silica-manganese oxides with a core-shell structure were synthesized via precipitation of manganese oxides on the $SiO_2$ core while varying the concentration of a precipitation agent. Elemental analysis, crystalline property investigation, and morphology observations using low- and high-resolution electron microscopes were applied to the synthesized silica-manganese oxides with the core-shell structure. As the concentration of the precipitating agent increased, the manganese oxide shells around the $SiO_2$ core sequentially appeared as $Mn_3O_4$ particles, $Mn_2O_3+Mn_3O_4$ thin layers, and ${\alpha}-MnO_2$ urchin-like phases. The prepared samples were assembled as electrodes in a supercapacitor with 0.1 M $Na_2SO_4$ electrolyte, and their electrochemical properties were examined using cyclic voltammetry and charge-discharge cycling. The maximum specific capacitance obtained was 197 F $g^{-1}$ for the $SiO_2-MnO_2$ electrode due to the higher electronic conductivity of the $MnO_2$ shell compared to those of the $Mn_2O_3$ and $Mn_3O_4$ phases.

강우모형의 서울지역 강우 재현성 검토

류성수(Ryu Seong Su),전환돈(Jun Hwan Don),김중훈(Kim Joong Hoon) 대한토목학회 2007 대한토목학회 학술대회 Vol.2007 No.10

파라미터 추정방법을 이용한 선형추진브러시리스 직류전동기의 속도-위치제어기 설계

박성수(Seong-Su Park),최중경(Jung-Keying Choi),변지섭(Ji-Seob Byeon),윤성은(Seong-Eun Yun),류정오(Jeong-Oh Ryu) 대한전자공학회 2001 대한전자공학회 학술대회 Vol.2001 No.6