http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Modular Intermeshing Co-rotating Twin Screw Extruder 내에서 제조된 PC/ABS 블랜드의 물리적, 유변학적 성질
방대석,정우형 금오공과대학교 2006 論文集 Vol.27 No.-
The physical properties and melt behavior of PC/ABS blends may be significantly affected by mixing equipments and processing conditions. In this study, the physical and rheological properties of PC/ABS blends in a modular interrneshing co-rotating twin screw extruder were investigated. PC and ABS were blended by different conditions such as different compositions of PC and ABS, and the several types of screw configurations in a modular interrneshing co-rotating twin screw extruder. After extrusion, the specimens were fabricated by injection molding. Then the physical properties were measured by tensile and Izod-irrpact tests. The melt behavior was observed with the capillary rheometer. Mixing and melting behaviors in the extruder were investigated by the cooling experiment for the different screw configurations.
치합형 역방향회전(Intermeshing Counter-Rotating) 이축스크류식 압출기내의 등온 비뉴토니언 흐름 분석
방대석,홍명혁,정영진 國立金烏工科大學校 産業技術開發硏究院 2002 産業技術開發硏究 Vol.18 No.-
A proper and correct formulation of an isothermal non-Newtonian flow in intermeshing counter-rotating twin screw extruder modules which accounts clearly for the positive pumping displacement mechanism is presented. Screw pumping characteristic curves were determined for various typical elements of the Leistritz modular intermeshing counter-rotating twin screw extruder.
박일현,이종근,윤관한,조동환,민병길,방대석 金烏工科大學校 2000 論文集 Vol.21 No.-
The Rayleigh ratio of benzene is a very important physical constant with which the integrated scattered intensity of laser light scattering can be converted into the absolute value. In this study temperature dependence of Rayleigh ratio of this solvent has been investigated with two different methods in the temperature range of 25-75℃. It was found that in the direct measurement the non-linear behavior of its Rayleigh ratio were observed as increasing temperature even if the scattering volume correction was applied to the scattered intensity of benzene. However the result of indirect measurement based upon the invariance of molecular weight of standard polystyrene polymer for any polymer solution temperature showed us that its temperature dependence up to 75℃ could be expressed with the Benoit's linear equation rather than the non-linear one. It seems that the scattered intensity in direct method has more complicate contributions at the elevated temperature. Further research works are necessary in order to solve such discrepancy clearly.
( Dae Hyeok Yang ),( Min Suk Lee ),( Jong Tae Ko ),( Yong Sik Kim ),( Moon Suk Kim ),( John M. Rhee ),( Gil Son Khang ),( Hai Bang Lee ) 한국조직공학과 재생의학회 2006 조직공학과 재생의학 Vol.3 No.3
Ultra high molecular weight polyethylene(UHMWPE) powders were impregnated into poly(methylmethacrylate)( PMMA) bone cement to improve the poor mechanical and thermal properties of the bone cement. But, the surface inertness of UHMWPE powder generated the poor bonding force with PMMA bone cement. The surface modification after pretreating UHMWPE powder with the three kinds of acid such as acetic, hydrochloric, and sulfuric acid has been carried out to advance the interfacial adhesion between UHMWPE powder and PMMA bone cement. The tensile strengths of reinforced PMMA bone cements with 3 wt% of surface-precoated UHMWPE powder with polyMMA after acids treatment were much higher than that(33.8 MPa) of 3 wt% of intact UHMWPE powder impregnated PMMA bone cement as well as were almost same as that(44.5 MPa) of conventional PMMA bone cement. Also, it was found that the curing temperatures of the composite PMMA bone cements were much lower than that(~103oC) of conventional PMMA bone cement. From these results, it was confirmed that acids treatment effectively modified the surface of UHMWPE powder. A possible mechanism for the surface modification of UHMWPE powder by acids treatment was proposed.
( Dae Sung Lee ),( Ki Bae Bang ),( Ji Yeon Kim ),( Yoon Suk Jung ),( Jung Ho Park ),( Hong Joo Kim ),( Yong Kyun Cho ) 대한장연구학회 2016 Intestinal Research Vol.14 No.1
Quality of life is closely related to anemia in patients with inflammatory bowel disease (IBD). Several studies have reported on anemia in patients with IBD in Western countries. This study investigated the prevalence and clinical characteristics of anemia in Korean patients with IBD. Methods: We reviewed the medical records of 92 patients with ulcerative colitis (UC) and 76 patients with Crohn’s disease (CD) who were followed regularly at a single tertiary medical center in Korea between January 2003 and December 2012. Hemoglobin (Hb) thresholds used to define anemia were <13.0 g/dL in men and <12.0 g/dL in women according to the World Health Organization criteria. We chose the lowest Hb level in each year as a representative value because Hb levels changed at each examination and anemia was associated with disease deterioration. The relationship between clinical variables and lowest Hb level was assessed. Results: The prevalence of anemia was 36.3% in patients with UC and 41.6% in patients with CD. Anemia in patients with CD was associated with hospital admission, 5-aminosalicylate (5-ASA) and infliximab treatment in men. Anemia in patients with UC was associated with hospital admission, oral steroid use, thiopurine and infliximab treatment in men. Conclusions: The prevalence of anemia in Korean patients with IBD was comparable to that of patients in Western countries. Anemia was associated with male patients with CD who were admitted to the hospital and received medications including 5-ASA and infliximab, and men with UC who were admitted to the hospital and received medications including oral steroids, thiopurine and infliximab. (Intest Res 2016;14:43-49)
Dae Yun Seo,Hyo Bum Kwak,Sung Ryul Lee,Yeun Suk Cho,In-Sung Song,Nari Kim,Hyun Seok Bang,Byoung Doo Rhee,Kyung Soo Ko,Byung Joo Park,Jin Han 한국영양학회 2014 Nutrition Research and Practice Vol.8 No.2
BACKGROUND/OBJECTIVES: Irisin, a newly identified hormone, is associated with energy homeostasis. We investigated whether aged garlic extract (AGE) and exercise training intervention could improve body weight, insulin sensitivity, skeletal muscle fibronectin domain containing protein 5 (FNDC-5) levels, and plasma irisin in high-fat diet (HFD). MATERIALS/METHODS: Male Sprague Dawley rats were fed a ND (normal diet, n = 5) or HFD (n = 28) for 6 weeks. After 6 weeks, all rats were divided into 5 groups for the next 4 weeks: ND, (normal diet, n = 5), HFD (high-fat diet, n = 7), HFDA (high-fat diet + aged garlic extract, n = 7), HFDE (high-fat diet + exercise, n = 7), and HFDEA (high-fat diet + exercise + aged garlic extract, n = 7). Exercise groups performed treadmill exercises for 15-60 min, 5 days/week, and AGE groups received AGE (2.86 g/kg, orally injected) for 4 weeks. RESULTS: Significant decreases in body weight were observed in the ND, HFDE, and HFDEA groups, as compared with the HFD group. Neither intervention affected the masses of the gastrocnemius muscle or liver. There were no significant differences in glucose levels across the groups. The homeostatic model assessments of insulin resistance were significantly higher in the HFD group, as compared with the ND, HFDA, HFDE, and HFDEA groups. However, skeletal muscle FNDC-5 levels and plasma irisin concentrations were unaffected by AGE or exercise in obese rats. AGE supplementation and exercise training did not affect skeletal muscle FNDC-5 or plasma irisin, which are associated with insulin sensitivity in obese rats. CONCLUSION: Our results suggest that the protection against HFD-induced increases in body fat/weight and insulin resistance that are provided by AGE supplementation and exercise training may not be mediated by the regulation of FNDC-5 or irisin.