Dynamic Young's Modulus and Internal Friction in Polycrystalline Copper

Kang, Chang-Seog,Chang, Si-Young,Hong, Sung-Kil 대한금속재료학회 2003 METALS AND MATERIALS International Vol.9 No.5

An attempt has been made to measure the temperature dependence of dynamic Young's modulus together with the related variation of internal friction in polycrystalline copper. A mechanical spectroscopy study was employed using a standard servo hydraulic fatigue testing machine equipped with a scanning laser extensometer. Dynamic Young's modulus and internal friction were measured over a temperature range of 298 to 873 K at very low frequencies of 0.1, 0.05, and 0.01 Hz. One internal friction peak was observed over the ranges 450 to 700 K, together with marked decreases in the dynamic Young's modulus in the same temperature range. From a quantitative analysis of the experimental data with the relaxation strength, relaxation time, and activation energy, it is concluded that the peak phenomenon is due to grain-boundary sliding relaxation.

고령자 급성 췌장염의 임상적 고찰

이진헌,강진경,박인서,송건훈,정재복,백용한,송시영,서정훈 대한소화기학회 1998 대한소화기학회지 Vol.32 No.3

Background/Aims: Inflammatory diseasas of the pancreas are not uncommon. The advanced age is one of the significant factors in assessing the severity of acute pancreatitis. It has been shown that the biliary tract disease is a more frequent cause of acute pancreatitis in the elderly than in the young. With the increased life span, the elderly are comprising a large proportion of the population. As a result, physicians are more often being faced with acute pancreatitis in the elderly. The purpose af this study was to evaluate clinical features of acute panereatitis in the elderly. Methods: A total of 188 patients with acute pancreatitis were reviewed. We investigated the differences of clinical characteristics between the elderly patients aged over 60 and the young patients aged under 60. Results: The sex distribution showed male preponderance in the young patients (M:F=2.4:1), but was nearly equal in the elderly patients (M:F=1.1:1). The most common cause of acute pancreatitis in the elderly was biliary tract disease (52.5%), while alcohol abuse was the most common cause in the young patients (38.8%), Local complications of acute pancreatitis, such as psuedocyst, necrosis, abscesses were not differently shown between the elderly (16.9%) and the young (20.2%) patients. Systemic complications including acute puhnonary failure occurred more frequently in the elderly patients than the young patients. The mortality rate of the elderly patients (5.1%) was not significantly different from that of the young patients (3.1%). Conclusions: To detect correctable underlying bihary tract diseases the elderly patients with acute pancreatitis should be completely investigated using endoscopic retrograde cholangiopancreatography (ERCP). In addition, the patient should be closely monitored for the development of the systemic complications during the disease process.

고령자 급성 췌장염의 임상적 고찰

백용한,서정훈,송건훈,이진헌,송시영,정재복,강진경,박인서,이수진 大韓消化器病學會 1998 大韓消化器病學會誌 Vol.32 No.3

A New Sesame Variety, “Kangbaek” with Disease Resistance, Lodging Tolerence and High Yield

Kang-Bo Shim,Churl-Whan Kang,Suk-Bok Pae,Si-Kyu Lim,Yu-Young Lee,Duck-Yong Suh,Jae-Whan Rho,Jin Song,Dong-Whi Kim,Ho-Young Kim 한국육종학회 2005 한국육종학회지 Vol.37 No.5

A new sesame variety Kangbaek was developed from Yeongnam Agricultural Research Institute in 2004. Cros wasmade by lodging resistant SP9003-3 line to the F1with high yielding capacity, folowed by pedigree selection, yield test and RYT by the sesame breeding team at the National Insti-tute of Crop Science up to 2003. The variety showed higher disease resistance, especially phytophothra disease, and lodging resis-respectively. It's 1000 grains weight was about 2.54 g indicating 0.03 g heavier than that of Yangbaekkae, and it's oil content wasabout 52%. Kangbaek also contained total 7.65mg/g of such lignans as sesamin and sesamolin. The average yield of Kang-baek was 82 kg per 10a at the national-wide regional performance.

Biomass 유래 퓨란계 단량체를 이용한 폴리에스터의 중합 및 특성 연구

정용석(Yong Seong Chung),이영철(Young Chul Lee),서강진(Kang Jin Seo),김명준(Myeong Jun Kim),정지혜(Ji Hea Jeong),노시태(Si Tae Noh) 한국고분자학회 2011 폴리머 Vol.35 No.6

바이오매스에서 유래된 2,5-dihydroxymethylfuran(DHMF)을 KMnO4 산화반응으로 furan-2,5- dicarboxylic acid(FDCA)를 합성하였다. 합성한 FDCA와 다이올류를 에스테르화 반응과 축중합 반응을 진행시 켜 폴리에스터를 중합하였다. 폴리에스터는 NMR을 통해 조성을 분석하였고 DSC와 TGA를 통해 열적특성을 분 석하였다. 합성된 폴리에스터의 고유점도는 0.78∼1.2 dL/g으로 상용화된 poly(ethylene terephthalate)(PET) 와 비슷하였다. 다이올의 길이가 증가할수록 Young`s modulus와 strength는 낮아지고 elongation-to-break는 높아지는 경향을 확인하였다. 합성한 poly(ethylene furandicarboxylate)(PEF)의 Young`s modulus는 3551 MPa, strength는 103 MPa로 상용화된 PET와 비슷하였다. Furan-2,5-dicarboxylic acid (FDCA) was synthesized by KMnO4 oxidation of 2,5-dihydroxymethylfuran( DHMF) derived from biomass. Polyesters were synthesized by esterification and polycondensation of FDCA with various diols(ethane-1,2-diol, propane-1,3-diol, butane-1,4-diol, hexane- 1,6-diol, decane-1,10-diol). The composition of polyesters was characterized by using 1H NMR. Thermal properties of the polyesters were characterized by DSC and TGA. Intrinsic viscosities(IV) of the polyesters were measured to be 0.78∼1.2 dL/g comparable with IV of commercial poly(ethylene terephthalate)(PET). As the chain lengths of diols increased, Young`s modulus and strength decreased and elongation-to-break generally increased. Young`s modulus and strength of the polyesters were measured to be 3551 MPa and 103 MPa, respectively, comparable with commercial PET.

오리 網膜에 存在하는 神經節細胞의 數와 分布에 關한 硏究

姜翰秀,金武剛,申台均,金弘善,柳時潤,李永浩 충남대학교 의과대학 지역사회의학연구소 1986 충남의대잡지 Vol.13 No.1

The number and distribution of the retinal ganglion cells in the 1-week-old and 7-week-old ducks were determined from whole flat mounted preparations stained with methylene blue and thionin. The results were summarized as follows. 1. In the 1-week-old and 7-week-old ducks, the areas of the retinas were 269.4㎟ and 357.2㎟, respectively, and the total cell numbers 1,742,800 and 1,808,800, respectively. 2. The ganglion cells based upon soma diameter were classified into 3 groups such as small (below 10㎛), medium (10-20㎛) and large (above 20㎛) ganglion cells. In 1-week-old duck, the relative frequencies of these 3 groups were 91.0%, 8.5% and 0.5%, respectively, and in 7-week-old duck, 83.7% 14.7% and 1.6%, respectively. 3. Area centralis was located at the distance of 1.6mm (1-week-old) and 2.0mm(7-week-old) nasal side from the anterior tip of the pecten. The number of ganglion cells in the area centralis was 11,000 cells/㎟ (1-week-old) and 12,000 cells/㎟ (7-week-old). 4. There was a gradual decrease in density of retinal ganglion cells extending from area centralis to the periphery of retina. 5. The density of the large (above 20㎛) ganglion cells was higher in the peripheral regions than in the center of retina. Higher densities were noted in the superior-temporal region in 7-week-old duck, and in the nasal region in 1-week-old duck than in the other regions. 6. The direction of the beak tip is approximately 30° in 1-week-old and 26° in 7-week-old duck from the angle of the pecten.

선박용 폐 FRP 수지의 재활용 공정 개발

강세란,김영우,황덕기,김시영,이민규,주창식 한국환경과학회 2003 한국환경과학회지 Vol.12 No.6

A recycling process for the waste FRP from boats was developed. The recycling process is composed of decomposition of waste FRP with propylene glycol and synthesis of recycled unsaturated polyester resin from the decomposed liquid material. Prior to the decomposition, waste FRP was cut into 2cm × 5cm segments and mechanical impact was applied by press roller to give gaps between cumulated laminates. Propylene glycol effectively decomposed the waste FRP segments and glass fibers were easily separated from decomposed liquid material. Recycled unsaturated polyester resin could be made from the decomposed liquid material by reaction with maleic anhydride and phthalic anhydride.

단체교섭의 메카니즘에 관한 연구

강정대,양시영 全北大學校 1996 論文集 Vol.42 No.-

With the democratization of industrial and labor relations in Korea, collective bargaining has emerged as the most important social phenomena. This study, through the examination of various bargaining power, style theories and comparison the model of bargaining partner of three countries, if aimed at finding out the sucessful bargaining model that can satisfy both labor and management. Bargaining partner model (1)Germany : The ability to conclude collective agreements (2)U.S.A. : Appropriate bargaining unit (3)Japan : Bargaining partner under the provisions of constitional law and trade union act Collective bargaining power various according to the viewpoint of bargaining power, collective bargaining power depends upon several complex requestes rather than a single one. The study on collective bargaining power theories has been made through several board approaches such as the economics approach, behavioral secience approach, integative approach(Kochan, T.A. & Katz, H.C.,). It is necessary to apply rigorous methodologies such as study on the bargaining partner in various types of bargaining, study on the bargaining power, and study on the strike-adjustment ability in order to expand the application of integrate collective bargaining study.

들깨잎의 揮發性 香氣成分에 關한 硏究

姜興順,林順英,南昌祐,尹錫權,邊時明 同德女子大學校 1995 同大論叢 Vol.25 No.1

To investigate the volatile flavor components of perilla leaves, analyses of kinds of cultivar by GC, GC/MS, UV, IR and NMR were carried out. The results obtained were summarized as follows : 1. The essential oils were extracted with diethyl ether after steam disillation. 2. The identified volatiles include 10 hydrocarbones, 6 alcohols, 3 aldehydes, 2 ketones and 1 miscellaneous components. 3. The major volatile component perilla ketone was identified by UV, IR and NMR spectrum. 4. The perilla ketone were identified in Suwon 8, 19, 21, 23, 24, 25, 26 and purpurea while perillaldehyde was identified in purpurea only.

일 간호대학의 지역사회 방문간호사업 사례

강윤숙,최양자,고영애,전시자,조갑출,이옥철,주혜경,신기수,안은숙 적십자간호전문대학 2000 적십자간호전문대학논문집 Vol.22 No.-