연구 논문 : 전기화학적 마이크로머시닝 기술을 이용한 균일한 니오븀 표면 에칭 연구

김경민 ( Kyung Min Kim ),유현석 ( Hyeon Seok Yoo ),박지영 ( Ji Young Park ),신소운 ( So Woon Shin ),최진섭 ( Jin Sub Choi ) 한국공업화학회 2014 공업화학 Vol.25 No.1

본 연구에서는 micro-contact printing을 통하여 니오븀 호일 표면 위에 균일한 에칭 pits를 형성하였다. 균일한 보호층을 형성하고자 전해연마의 효과를 확인하였으며, 기존의 O2 플라즈마 공정 없이 손쉽게 균일한 에칭 pits를 형성시킬 수 있는 조건을 확인하였다. 메탄올 혼합 전해질을 사용하여 10 min 동안 에칭을 진행한 결과 니오븀 호일 표면 위에 지름과 간격이 각각 10 μm와 5 μm로 잘 정렬된 에칭 pits를 관찰하였다. We describe the preparation of highly-ordered etching pits on the Nb foil through a micromachining. The effects of electro-chemical polishing on the formation of uniformly-patterned protective epoxy layer was investigated. Unlike the previous proc-ess using O2 plasma, well-ordered etched pits were prepared without any dry processes. As a result, the Nb foil with the well-ordered pits of 10 μm × 5 μm could be obtained by electrochemical etching in methanolic electrolytes for 10 min.

Studies on Lytic, Tailed Bacillus cereus-specific Phage for Use in a Ferromagnetoelastic Biosensor as a Novel Recognition Element

( In Young Choi ),( Joo Hyeon Park ),( Kyoung Min Gwak ),( Kwang-pyo Kim ),( Jun-hyun Oh ),( Mi-kyung Park ) 한국미생물생명공학회(구 한국산업미생물학회) 2018 Journal of microbiology and biotechnology Vol.28 No.1

This study investigated the feasibility of the lytic, tailed Bacillus cereus-specific phage for use in a ferromagnetoelastic (FME) biosensor as a novel recognition element. The phage was immobilized at various concentrations through either direct adsorption or a combination of 11-mercapto-1-undecanoic acid (11-MUA) and [N-(3-dimethylaminopropyl)-N’-carbodiimide hydrochloride and N-hydroxysuccinimide (EDC/NHS)]. The effects of time and temperature on its lytic properties were investigated through the exposure of B. cereus (4 and 8 logCFU/ml) to the phage (8 logPFU/ml) for various incubation periods at 22°C and at various temperatures for 30 and 60 min. As the phage concentration increased, both immobilization methods also significantly increased the phage density (p < 0.05). SEM images confirmed that the phage density on the FME platform corresponded to the increased phage concentration. As the combination of 11-MUA and EDC/NHS enhanced the phage density and orientation by up to 4.3-fold, it was selected for use. When various incubation was conducted, no significant differences were observed in the survival rate of B. cereus within 30 min, which was in contrast to the significant decreases observed at 45 and 60 min (p < 0.05). In addition, temperature exerted no significant effects on the survival rate across the entire temperature range. This study demonstrated the feasibility of the lytic, tailed B. cereus-specific phage as a novel recognition element for use in an FME biosensor. Thus, the phage could be placed on the surface of foods for at least 30 min without any significant loss of B. cereus, as a result of the inherent lytic activity of the B. cereus-specific phage as a novel recognition element.

연구보문 : 자연과학 ; 황산처리에 의한 불투수성 황근 종자의 발아촉진에 관한 연구

서상흠 ( Sang Heum Seo ),박민우 ( Min Woo Park ),장미하 ( Mi Ha Chang ),장일웅 ( Il Ung Jang ),심상인 ( Sang In Shim ),나영왕 ( Young Wang Na ),김수영 ( Soo Young Kim ),김석현 ( Seok Hyeon Kim ) 한국국제농업개발학회 2012 韓國國際農業開發學會誌 Vol.24 No.3

The reason of poor germination rate of hamabo mallow seed was speculated using TZ test to determine the viability of seed. Seeds showed high viability via TZ test were not germinated well. The quiescent seeds did not imbibed properly due to the hard seed coat and did not show further processes required for germination. Several well-known treatments for seed coat loosening and water uptake into seed were applied and compared for their efficiency. Stratification, hot water treatment, seed coat scarification, wet-cold treatment were revealed as less effective for improving germination although those treatments were common method for breaking dormant seed. Chemical scarification with sulfuric acid, however, effectively increased germinability and promptness index of hamabo mallow seeds. Optimal time for sulfuric acid treatment was 20 min. Seeds treated for 20 min showed improved germination percentage, germination speed, and promptness index of 80%, 13, and 1969 at 30 days after imbibition, respectively, in petri dish experiment. The values were greater than control seeds showed low values (12%, 1, and 183, respectively). The similar tendency was observed in the pot experiment that sulfuric acid treated seed were sown in artificially mixed soil (loamy soil:peatmoss:sand:compost = 5:2:2:1) and placed in greenhouse. Ultrastructure analysis of chemically scarified seed with sulfuric acid for 20 min by scanning electron microscopy did not show any noticeable changes in seed coat hardness and water uptake via hilum. But the only change after sulfuric acid treatment was removal of hilum cap that close the hilum and hider imbibition. Therefore, subsequent experiment was conducted to know the relationship between removal of hilum cap and facilitated imbibition by sulfuric acid treatment and whether the hilum cap removal directly influenced to the opening of micropyle. Water uptake velocity of seed treated for 20 min in concentrated sulfuric acid for was greater than control seed. This result implies that the crucial effect of sulfuric acid treatment is the removal of hilum cap that increase water uptake via micropyle in hamabo mallow.

여성 하부요관석환자에서 무마취하 요관경하 배석술

박영호,송윤섭,임용순,김영호,이남규,구자현,서병욱,김민의,전윤수 순천향의학연구소 1999 Journal of Soonchunhyang Medical Science Vol.5 No.2

Although ureteroscopy(URS) has been used widely to remove ureteral calculi, there is an argument against the belief that anesthesia or admission is needed for URS. We evaluated the experience of URS without anesthesia in female patients. From September 1997 to July 1998, URS was performed in 31 female patients without anesthesia. EHL(Electrohydraulic Lithotripsy) was used in 21 patients with impacted or large stone over 5mm. All patients were given oral antibiotics for 3 days and follow-up KUB was taken to confirm successful removal of the stone one week after the procedure. Successful treatment was defined as complete removal of the stone or residual fragments less than 2mm. Overall success rate was 96.7%(30 cases among 31 cases). All but one patient tolerated with analgesia through the entire procedures. There were only minimal complications such as mild flank pain and hematuria. So, we recommend that non-anesthetic ureteroscopic removal of stone as the first choice for treatment of lower ureteral stones in female based on the minimal morbidity, high success rate and low cost.

스트룹 테스트와 단순반응 테스트의 훈련 향상도에 관한 연구

조현우,박영민,박사엘,공추,왕초전,장신,김재화 순천향대학교 기초과학연구소 2022 순천향자연과학연구 논문집 Vol.28 No.1,2

This study which of the Stroop test training and simple response training can reduce the Stroop effect in the information processing process when continuous training is performed. 4 male students from S University(Asan-si) were divided into Stroop test training group(2) and simple reaction group(2). The test was conducted 10 times a day, and average was obtained and analyzed. The results encountered through this study are as follows. 1 The simple response training group improved more slowly than the Stroop test training group. 2. In the Stroop test training group, the rate of increase increased significantly compared to the simple response training group, but it did not increase once the record reached a certain point. 3. Simple response training at increasing values ​​was also trained on the Stroop effect. 4. In the average of phage values, both groups look similar.

치과용 금합금의 표면처리에 따른 교정용 브라켓의 전단결합강도 변화

민지현,황현식,이기헌,박병주 전남대학교 치과대학 2000 전남치대논문집 Vol.12 No.1

A bracket bonding to the dental gold alloy shows a lower bond strength than the natural teeth, and this can be a possible source of subsequent bond failure. This study aims to evaluate the effect of various gold alloy surface treatment techniques on shear bond strength between the orthodontic adhesives and the gold alloy and to find ways of increasing the bond strength. Two hundred and forty specimens made of the dental gold alloy were divided into twelve groups based on the combination of surface treatment methods(non-surface treatment, sandblasted, sandblasted plus tin-plated, and sandblasted plus intermediate adhesive) and adhesive systems(Ortho-one, Panavia 21, Superbond C&B). The specimens with brackets bonded were placed in distilled water at 37℃ for 24 hours and shear bond strength was measured by a universal testing machine. The results were as follows: 1. All surface-treated groups showed a significantly higher shear bond strength than non-surface-treated groups. 2. The sandblasted plus tin-plated group showed a significantly higher shear bond strength than the sandblasted group only when Panavia 21 was involved. 3. The sandblasted plus intermediate adhesive group showed a significantly higher shear bond strength than sandblasted group regardless of the type of adhesive used. 4. Of the three resin adhesive types, the Superbond C&B showed the highest bond strength, followed by Panavia 21 and Ortho-one. These findings suggest that a combination of sandblasting and intermediate resin treatment is desirable in order to enhance bracket bond strength regardless of adhesive types.

비수도권 대학생 임대주거 실태 및 요구

박경옥, 송민경, 이종현 충북대학교 생활과학연구소 2013 생활과학연구논총 Vol.17 No.2

The purpose of this study is to propose the renal housing policy direction for undergraduates based on their actual rental housing conditions and needs who reside in non capital area. For the study, questionnaires were answered by 315 undergraduates of 3 universities who reside in rental housings in Cheongju-city. Major findings were as follows: (1) Most of undergraduate rental housings had the size from 12㎡ to 29㎡ and from 29㎡ to 41㎡, were multi-household studio type with room+bath+kitchen, and were typically monthly rent payment. (2) The needs of rental housings were the same as present residence. The possible monthly rent were mostly 300 thousand won, and the most preferred distance was under 10 minute walk from university. The assistance policy that undergraduates need was firstly the central/local governments' refurbished housing supply near university with low rent, and then deposited housing supply for undergraduates by LH corporation.

알루미늄과 헤테로폴리산으로 개질된 메조포러스 실리카 상에서의 AKD 합성

김현국,우창수,최재석,박민태,이병민,이호인 한국공업화학회 2003 응용화학 Vol.7 No.1

AKD(alkyl ketene dimer) used widely as a neutral sizing agent is produced industrially by halogenization of stearic acid followed by dimerization of alkyl ketene. In the present work, to suppress the byproduct of hydrochloric acid and to improve reaction pathway. AKD was prepared through of ketene intermediate by dehydration of stearic acid in gas phase using reaction with silanol on silica as active sites of the catalyst SBA-15 showed the highest activity due to the large and open tubular pores. It was found that main products were dimer and trimer. Our goal of the present work was to increase of the selectivity for the dimer.

톨루엔 노출 근로자에서 유전자적 요인, 생활습관 및 식이가 요중 마뇨산 배설에 미치는 영향

임현우,박정일,노영만,이강숙,이정민,이원철,이세훈,정치경 大韓産業醫學會 2000 대한직업환경의학회지 Vol.12 No.3

목 적 : 본 연구는 생물학적 지표 특성 연구를 위한 단면조사 연구로서 톨루엔 노출과 톨루엔의 생물학적 모니터링으로 이용되는 요중 마뇨산 농도간의 양-반응 관계에서 효과 변경인자로서 작용하는 유전자 ALDH2, CYPIAI, CYP2El의 다양성 분포를 조사하고, 이들 유전자가 요중 마뇨산 배설 농도에 미치는 영향을 알아보고자 하였다. 방 법 : 연구대상자는 경인지역에 위치한 22개의 사업체에서 페인트 제조 72명, 제조업에서 도장작업 50명, 인쇄업 12명, 접착작업 12명, 벽지의 코팅작업 14명등 160명의 근로자이었다. 성, 연령, 유기용제 작업장 근무경력, 흡연습관, 음주습관, 검사일 이전 밤에 음주 여부, 시료 채취전 6시간 이내에 섭취한 식품조사, 측정일 개인보호구의 착용 여부에 대하여 설문조사를 시행하였다. 톨루엔에 대한 개인노출량은 passive air sampler로 측정하였고, 요중 마뇨산은 요중 크레아틴으로 보정하여 측정하였다. 또한 aldehyde dehydrogenase 2 (ALDH2) , cytochrome P45O IAI(CYPIAI), 그리고 cytochrome P45O 2El(CYPfEl)의 유전적 다양성은 혈액으로부터 백혈구의 DNA를 추출하여 제한 효소 절단 길이 다양성 (restiction fragment length polymorphism, RFLP)법으로 검사하여 다음의 결과를 얻었다. 결 과 : 연구대상자의 요중 마뇨산 농도의 기하평균은 0.44g/g creatinine, 기하표준편차 2.80이었다. 톨루엔 노출 농도, 개인 보호구 착용여부, 안식향산이 함유된 식품의 섭취여부중 요중 마뇨산 배설농도에 영향을 미치는 인자는 톨루엔 노출 농도뿐이었다. ALDH2, CYPIAI, CYPfEl, 연령, 흡연, 근무기간에서 회귀계수간에 차이를 보이는 경향이 있었다. 요중 마뇨산 농도에 대한 다중회귀분석에서 톨루엔, ALDH2, CYPIAI, CYP2El유전자형의 회귀계수가 통계적으로 유의하였다. 결 론 : 톨루엔 노출로 인한 요중 마뇨산 배설 농도는 ALDH2, CYPIAI, CYP2El유전자 다양성에 의해 영향을 받기 때문에, 유전자형의 대사능의 차이를 고려하여 마뇨산 기준 농도를 찾는 연구가 이루어져야 하겠다. Objectives The purpose was to investigate the distributions and the effects of genetic polymorphism of aldehyde dehydrogenase 2(ALDH2), cytochrome P45O IAI (CYPIAI), and cytochrome P45O 2El (CYPfEl) on the toluene metabolism. Methods : The subacts consisted of 160 workers who were exposed to toluene in different industries such as paint manufacturing, painting on steel and wood products, printing, bonding, and coating. The exposed toluene level was monitored by passive air sam paler, and the questionnaire variables were age, sex, smoking, drinking, previous night's drinking, use of personal protectlve equipment, work duration, and taking benzoic acid containing food. The urinary hippurric acid collected in the end of shift was corrected by urinary creatinine concentration. The genotypes of ALDH2, CYPIAI, and CYP2El were investigated using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methods with DNA extracted from venous blood. Results'The geometric mean and the geometric standard deviation of urinary hippuric acid concentration were 0.44 g/g creatinine and 2.80. The urinary hippuric acid concentration was significantly related to personal exposed toluene level among personal exposed toluene level, use of personal protective equipment, and benzoic acid containing food diet. The slope differences of the regression for ALDH2, CYPIAI, and CYP2E1 genetic polymorphism, age, smoking, and work duration tended to be significant. In multiple regression analysis, the regression coefficient of toluene, ALDH2, 7YPIAl, CYP2E1 genetic polymorphism were significant. Conclusions : From the above results, urinary hippuric acid level after toluene exposure was significantly affected by the genetic polymorphism of ALDH2, CYPIAI, CYPfEl. It is needed further investigation of the urinary hippuric acid level considering the effect of genetic polymorphism.

무증상의 현미경적 혈뇨의 비뇨기과적 고찰

구자현,서병욱,김영호,송윤섭,전윤수,김민의,이남규,박영호 순천향의학연구소 1998 Journal of Soonchunhyang Medical Science Vol.4 No.2

We intended to know whether all of the patients with asymptomatic microscopic hematuria should be urologically investigated routinely. We reviewed the medical records with asmptomatic microscopic hematuria from January 1995 to December 1997. Urological studies included intravenous urography or ultrasonography, urine cytology, cystoscopy and biopsy, urine AFB smear and culture and urine PCR for AFB. The age with patients ranged from 9 to 74 years(mean age: 39.7 years). Benign diseases were found in elderly patients and patients with high degree of hematuria, but there was no patients who had urological malignant disease. According to the results, we suggest that follow-up with urine cytology is sufficient to younger patients or low degree of hematuria with asymptomatic microscopic hematuria.