가스가 주입된 용기에서 기공율, 기포빈도와 온도측정에 관한 연구

박설현,오율권,서동표 朝鮮大學校 機械技術硏究所 1999 機械技術硏究 Vol.2 No.2

The local phase volume fraction, bubble frequency and the phase temperature distributions were measured in vertical air injected water baths. An electroresistivity probe was employed for the determination of the local void fraction and bubble arrival frequency. The phase resolved temperatures were measured using a microthermocouple. The thermocouple signals were digitally filtered, and were carried out to characterize the overall structure of the gas-liquid plume and the heat transfer mechanism between the phases.

배관내에서 난류 마찰 저항감소에 관한 연구

박설현,윤정환,서동표,정대훈,오율권 朝鮮大學校 機械技術硏究所 2000 機械技術硏究 Vol.3 No.1

Polymer drag reduction can offer a attractive way to utilize ready-made facilities in crude-oil transport system without additional large expenditure. Also, drag reduction in two phase flow can be applied to phase change system such as chemical reactor, pool and pump impeller which occurs cavitation. But the research on drag reduction in two phase flow has not been investigated. Therefore, experimental investigations have been carried out to analyze the drag reduction in the single phase and two phase flow. The objectives of the proposed investigation are primarily to identify and develop high performance polymer additives for fluid transportation. And drag reduction will be evaluated in horizontal flow by measuring void fraction, pressure drop, mean liquid velocity and turbulent intensity

초음파 진동이 가진된 밀폐용기에서 상변화 열전달 특성

박설현,정대훈,오율권 조선대학교 에너지.자원신기술연구소 2001 에너지·자원신기술연구소 논문지 Vol.23 No.1

Solid-liquid phase change (i.e. melting or solidification) occurs in a number of situations of practical interest. Some common examples include the melting of edible oil. metallurgical process such as casting and welding, and materials science applications such as crystal growth. Therefore, due to the practical importance of the subject, there have been a large number of experimental and numerical studies of problems involving phase change during the past few decades. This study presents experimental work on phase change heat transfer. Especially, in order to increase heat transfer rate. ultrasonic vibrations were introduced. The melting cavity contained one vertical heating surface which dissipates heat at constant power and was insulated on the sides. Experimental observations show that the effect of ultrasonic vibrations on heat transfer is very important throughout melting process. The results of this study reveal that ultrasonic vibrations accompany the effects like agitation, acoustic streaming, cavitation, and oscillating fluid motion. Such effects are a prime mechanism in the overall melting process when ultrasonic vibrations are applied. They speed up the melting process as much as 2.5 times, compared with the result of natural melting. Also, energy can be saved by applying ultrasonic vibrations to the natural melting.

Distribution of the Fairy Pitta (Pitta nympha) in the South Korea: A focus on protected areas

Gil-Pyo Hong(홍길표),Jae-Hoon Kim(김재훈),Seul-Gi Seo(서슬기),So-Yeon Cho(조소연),Bo-Yeon Hwang(황보연),Jong-Hyun Park(박종현),Seung-Yeon Lee(이승연),Ga-Young Kim(김가영),Wan-Hee Nam(남완희),Ha-Cheol Sung(성하철) 한국조류학회 2021 한국조류학회지 Vol.28 No.2

국내 팔색조(Pitta nympha) 분포 현황을 알아보고자 전국 국립공원 등 보호지역 중심으로 총 19개 지역을 조사하였고, 전문가 네트워크를 통해 자료를 보강하였다. 전국 19개 지역을 조사한 결과 북한산, 지리산 등 내륙지역 7개 국립공원에서는 팔색조가 확인되지 않았고, 경남 거제, 남해, 해남, 장흥 고흥 등 남해안과 인접한 12개 지역에서 팔색조 서식이 확인되었다. 또한 전문가 네트워크를 통해 수집한 팔색조 출현 위치 정보 82건을 분석한 결과, 전국 8개 광역지자체 모두 팔색조 서식이 확인되었고, 내륙지역(26.8%)보다 해안지역(73.2%)에서 더 많이 출현하였다. 연구 결과를 종합해보면, 우리나라의 팔색조는 주로 제주도와 남해안 지역을 중심으로 많이 분포하며, 그 보다 적은 개체수가 내륙 지역에 넓게 분포하고 있는 것으로 나타났다. The present study investigated the current distribution of Fairy Pitta (Pitta nympha) in South Korea. A total of 19 study areas, including protected areas such as national and provincial parks in South Korea were surveyed, and additional data obtained from an expert network. According to the results, Fairy Pitta was absent in seven inland national parks, including Mt. Bukhan and Chiri parks. Fairy Pitta inhabited 12 areas near the southern coast of South Korea, including Geoje, Namhae, Haenam, Jangheung, Goheung, and Gyeongnam Province. The analysis results of 82 datasets obtained from experts with regard to the locations where Fairy Pitta have been spotted showed that the bird inhabits all the eight metropolitan regions in South Korea, and is more frequently spotted in coastal areas (73.2%) than in inland areas (26.8%). The findings demonstrate that Fairy Pitta is mainly distributed in Jeju Island and the southern coast of South Korea, and is distributed in inland areas at relatively lower numbers.

A single chemosensor for multiple analytes: fluorogenic detection of Zn²⁺ and OAc⁻ ions in aqueous solution, and an application to bioimaging

Park, Gyeong Jin,Na, Yu Jeong,Jo, Hyun Yong,Lee, Seul Ah,Kim, Ah Ram,Noh, Insup,Kim, Cheal The Royal Society of Chemistry 2014 NEW JOURNAL OF CHEMISTRY Vol.38 No.6

<P>A new highly selective and sensitive chemosensor <B>1</B> for both Zn<SUP>2+</SUP> and OAc<SUP>−</SUP> with off–on fluorescence behavior in aqueous solution was developed. The selectivity mechanism of <B>1</B> for zinc is based on a combinational effect of the inhibition of excited-state intramolecular proton transfer and C&z.dbd;N isomerization, and chelation-enhanced fluorescence. As a practical application, <I>in vitro</I> studies with fibroblasts showed fluorescence in the presence of both the receptor <B>1</B> and Zn<SUP>2+</SUP>. Moreover, the deprotonated <B>1</B> can behave as a chemosensing system for turn-on detection of OAc<SUP>−</SUP> in preference over various other anions tested. Therefore, <B>1</B> can serve as ‘one sensor for multiple analytes’.</P> <P>Graphic Abstract</P><P>A single fluorescent chemosensor <B>1</B> for multiple analytes (Zn<SUP>2+</SUP> and OAc<SUP>−</SUP>) has been developed and it can monitor Zn<SUP>2+</SUP> ions in living cells. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c4nj00191e'> </P>

High Glucose-induced <i>O</i>-GlcNAcylated Carbohydrate Response Element-binding Protein (ChREBP) Mediates Mesangial Cell Lipogenesis and Fibrosis : THE POSSIBLE ROLE IN THE DEVELOPMENT OF DIABETIC NEPHROPATHY

Park, Min-Jung,Kim, Dong-Il,Lim, Seul-Ki,Choi, Joo-Hee,Han, Ho-Jae,Yoon, Kyung-Chul,Park, Soo-Hyun American Society for Biochemistry and Molecular Bi 2014 The Journal of biological chemistry Vol.289 No.19

<P>Carbohydrate response element-binding protein (ChREBP) is a transcription factor responsible for carbohydrate metabolism in the liver. However, the role of ChREBP in diabetic nephropathy has not been elucidated. Thus, we investigated the role of ChREBP in mesangial cells in diabetic nephropathy. Treatment with 25 m<SMALL>m</SMALL> glucose (high glucose; HG) increased cellular <I>O</I>-GlcNAc and <I>O</I>-GlcNAcylated ChREBP in mesangial cells compared with normal 5.5 m<SMALL>m</SMALL> glucose. <I>O</I>-(2-acetamido-2-deoxy-<SMALL>d</SMALL>-glucopyranosylidene) amino <I>N</I>-phenylcarbamate (PUGNAc), a drug that increases <I>O</I>-GlcNAc, augmented the expression of ChREBP targets, whereas DON, a drug that decreases <I>O</I>-GlcNAc and <I>O</I>-GlcNAcase overexpression, mitigated the increase with HG. <I>O</I>-GlcNAc augmented the protein stability, transcriptional activity, and nuclear translocation of ChREBP. HG treatment also stimulated lipid accumulation and the contents of triglyceride and cholesterol in mesangial cells. In addition, HG triggered expression of hypoxia-inducible factor 1-α, vascular endothelial growth factor, and extracellular matrix components related to nephrosclerosis. The ChREBP mutant, W130A, did not exhibit HG-induced lipid accumulation and fibrotic proteins, suggesting that the Trp-130 residue in the MCR3 domain is important in the development of glomerulosclerosis. <I>O</I>-GlcNAcylated ChREBP was elevated in mesangium cells of streptozotocin-induced diabetic rats. In conclusion, HG increased the <I>O</I>-GlcNAcylated ChREBP level, which resulted in lipid accumulation and up-regulation of fibrotic proteins in mesangial cells. These effects may lead mesangial cells to an ultimately pathological state.</P>

Quality Characteristics of Chicken Emulsion Sausages with Different Levels of Makgeolli Lees Fiber

Park, Kwoan-Sik,Choi, Yun-Sang,Kim, Hack-Youn,Kim, Hyun-Wook,Song, Dong-Heon,Hwang, Ko-Eun,Choi, Seul-Gi,Kim, Cheon-Jei Korean Society for Food Science of Animal Resource 2012 한국축산식품학회지 Vol.32 No.1

Makgeolli lees is a by-product of the makgeolli brew processing. Makgeolli lees contains high levels of fibers, which can be separated and used to develop foods rich in dietary fibers. The purpose of this study was to determine the effect of makgeolli fibers (0-4%) on proximate composition, caloric content, pH, color, cooking yield, textural profile, and sensory characteristics of chicken-emulsion sausages. The moisture content of 1, 2, and 3% makgeolli lees fiber-amended product was higher than the control, while that of the 4% product was not. Total calorie estimates of makgeolli lees fiber-amended sausages were lower than the control, except for in the case of the 4% treatment. Moreover, chicken sausages supplemented with makgeolli lees fiber had higher cooking yields and improved textural properties. Chicken emulsion sausages prepared with makgeolli lees fiber had improved overall acceptability, and the best results of sensory characteristics were obtained for the emulsion sausages containing 2% makgeolli lees fiber.

[P8-29] Korean Cibotium barometz as a Potent Inhibitor against an iNOS Expression via an Inhibition of NF-kB in LPS-Induced RAW 264.7 Macrophage Cells

Seul Lee,Chang Hyun Jin,Young Man Lee,Hyo Jung Lee,Ji Young Oh,Yong Dae Park,Myung Woo Byun,Hong Sun Yook,II Yun Jeong 한국식품영양과학회 2007 한국식품영양과학회 학술대회발표집 Vol.2007 No.10

산림경영협업체 공동소득사업에 관한 연구 : 진안 , 장성 , 순천지역 산림경영협업체를 중심으로 Focused on Forest Management Cooperatives Located in Chinan , Changseong , Sunchon Regions

박종민,이상현,이창헌,강학모,설동근 한국산림경제학회 1999 산림경제연구 Vol.7 No.2

This study was carried out to comprehend management realities and problems of joint enterprise of Forest Management Cooperatives, of which has been expending to accomplish sound and effective management since 1995, and to set active promotion plans of their joint enterprise. The study regions came from Chinan in Chonbuk, Changseong and Sunchon in Chonnam, where Forest Management Cooperatives were organized first. Investigation were performed to each president of Forest Management Cooperatives with interviews for two months from mid January to mid March in 1998 to get information and progress such as : scales and sorts of enterprise; composition of working expenses; the main group of crop cultivation and management; marketing; and fund raising. The interviews were carried out with 10 members of each Joint Enterprise, total 90 members, who were selected randomly to get information of members' inclinations about the objectives and participations in cooperatives, the problems and details of cooperatives, members' responsibilities and developmental plans for cooperatives and fund raising. In results, the working expenses were raised from national and provincial expenditures without self-helping of Forest Management Cooperatives' members, and the cultivation and management of crops were mainly maintained by the each chief of Forest Management Cooperatives with assistance of Training and Extension Service Center. In some regions, joint enterprise sometimes failed because there were lack of techniques of cultivation and management, no interesting of members, difficulty of security of members' labor, and lack of working expenses. The sorts and scales of joint enterprise were almost determined by government without considering characteristics of each Forest Management Cooperatives. Most members were answered that they did not know about the details of cooperatives and the problems in management which were progressing at the time of investigations. And also, most of answers were passive, such as support expansion of government and no sense about questions larder than active answers such as, composition of small groups for cultivations and member's participations. Therefore, more active programs will be need to induce members' concerns and participations for sound management of cooperatives.

Annealed Au-Assisted Epitaxial Growth of Si Nanowires: Control of Alignment and Density

Park, Yi-Seul,Jung, Da Hee,Kim, Hyun Ji,Lee, Jin Seok American Chemical Society 2015 Langmuir Vol.31 No.14

<P>The epitaxial growth of 1D nanostructures is of particular interest for future nanoelectronic devices such as vertical field-effect transistors because it directly influences transistor densities and 3D logic or memory architectures. Silicon nanowires (SiNWs) are a particularly important 1D nanomaterial because they possess excellent electronic and optical properties. What is more, the scalable fabrication of vertically aligned SiNW arrays presents an opportunity for improved device applications if suitable properties can be achieved through controlling the alignment and density of SiNWs, yet this is something that has not been reported in the case of SiNWs synthesized from Au films. This work therefore explores the controllable synthesis of vertically aligned SiNWs through the introduction of an annealing process prior to growth via a Au-catalyzed vapor–liquid–solid mechanism. The epitaxial growth of SiNWs was demonstrated to be achievable using SiCl<SUB>4</SUB> as the Si precursor in chemical vapor deposition, whereas the alignment and density of the SiNWs could be controlled by manipulating the annealing time during the formation of Au nanoparticles (AuNPs) from Au films. During the annealing process, gold silicide was observed to form on the interface of the liquid-phase AuNPs, depending on the size of the AuNPs and the annealing time. This work therefore makes a valuable contribution to improving nanowire-based engineering by controlling its alignment and density as well as providing greater insight into the epitaxial growth of 1D nanostructures.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/langd5/2015/langd5.2015.31.issue-14/la503453b/production/images/medium/la-2014-03453b_0008.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/la503453b'>ACS Electronic Supporting Info</A></P>