• 동의생리병리학회지
• /
• 제18권1호
• /
• pp.187-193
• /
• 2004

Constipation is a common clinical problem that comprises of symptoms that include excessive straining, hard feces, feeling of incomplete evacuation and infrequent defecation. Although many conditions, such as metabolic problems, fiber deficiency, anorectal problem, an drug, can cause constipation. This study was examined the effects of Chilsun-Whan on intestinal mucosa and gastrointestinal transit time and plasma lipids in rats. Adult male rats were fed for weeks on diets containing no addition(basal diet group), 5% cellulose(cellulose group) and 2.5% . Chilsun-Whan group(Chilsun-Whan group). The results were as follows; 1. The fecal weght was significantly increased 2 times in Chilsun-Whan administrated group compare to basal diet group. 2. The gastrointestinal transit times was significantly decreased in Chilsun-Whan administrated group compare to basal diet. 3. Carmine red mixed with Chilsun-Whan, as a marker, was administered through a gastric tube for stomach or intracecally by a chronically implanted catheter for colon transit. Small intestinal transit and large intestinal transit time were significantly decreased in Chilsun-Whan administrated group compare to basal diet. 4. The height of jejunal villi was developed in Chilsun-Whan administrated group compare to basal diet The thickness of mucosa and muscle layer of colonic mucosa were significantly developed in Chilsun-Whan administrated group compare to basal diet group. 5. The change of goblet cell in colonic mucosa was increased acid mucin stained alcian blue in Chilsun-Whan administrated group compare to basal diet and cellulose group. 6. HDL-cholesterol of plasma lipid was increased in Chilsun-Whan administrated group compare to basal diet and cellulose groups. Theses results suggests that Chilsun-Whan may be used in prevention and treatment of constipation resulting in increase of fecal weight, decrease of gastrointestinal transit time. development of intestinal villi, intensify of stainability of acid mucin in colon.

• 펄프종이기술
• /
• 제33권4호
• /
• pp.15-20
• /
• 2001

The function of the moisture-proof paper is to prevent moisture from adsorbing into the packed goods. Water-vapor transmission rate of the moisture-proof paper should be less than 100g/$m^2$.24hr and the optimum rate would be less than 50g/$m^2$.24hr. In general the moisture-proof paper has been made by laminating polyethylene or polypropylene on top of the base paper. However this kind of moisture-proof paper has a problem in recycling so that it brings about environmental pollution. In general the moisture-proof paper has been made by laminating polyethylene or polypropylene on top of the base paper. However this kind of moisture-proof paper has a problem in recycling so that it brings about environmental pollution. The purpose of this paper was to make moisture-proof paper using the mixture of SB latex and wax emulsion which was recyclable and environmentally friendly. Water vapor transmission rate showed less than 50g/$m^2$.24hr in mixture ratio of 85:15, 87:13, 90:10. Especially the mixture ratio of 87:13 showed the most favorable water-vapor transmission rate. However, the moisture-proof layer was destroyed slightly by folding in packing. It has been observed that there was no close relationship between water-vapor transmission rate of the moisture-proof paper and grammage of the base paper, but the density of base paper had influenced on water vapor transmission rate. It was also observed that the moisture-proof paper could be recycled. The moisture-proof paper was similar to base paper in degree of the pulping, and there was no significant difference in dispersion between moisture-proof paper and base paper. Most of wax particles which caused the spots during drying process could be removed by flotation process. Tensile strength and tear strength of both moisture-proof paper and base paper after pulping were measured to examine the fiber bonding, and no significant difference in physical properties was observed.

• 한국의류학회지
• /
• 제39권2호
• /
• pp.247-256
• /
• 2015

This study prepared fabric-heating elements of carbon nanofiber composite to characterize morphologies and electrical properties. Carbon nanofiber composite was prepared with 15wt% PVDF-HFP/acetone solution, and 0, 1, 2, 4, 8, and 16wt% carbon nanofiber. Dispersion of solution was conducted with stirring for a week, sonification for 24 hours, and storage for a month, until coating. Carbon nanofiber composite coated fabrics were prepared by knife-edge coating on nylon fabrics with a thickness of 0.1mm. The morphologies of carbon nanofiber composite coated fabrics were measured by FE-SEM. Surface resistance was determined by KS K0555 and worksurface tester. A heating-pad clamping device connected to a variable AC/DC power supply was used for the electric heating characteristics of the samples and multi-layer fabrics. An infrared camera applied voltages to samples while maintaining a certain distance from fabric surfaces. The results of morphologies indicated that the CNF content increased specifically to the visibility and presence of carbon nanofiber. The surface resistance test results revealed that an increased CNF content improved the performance of coated fabrics. The results of electric heating properties, surface temperatures and current of 16wt% carbon nanofiber composite coated fabrics were $80^{\circ}C$ and 0.35A in the application of a 20V current. Carbon nanofiber composite coated fabrics have excellent electrical characteristics as fabric-heating elements.

• 한국염색가공학회지
• /
• 제21권1호
• /
• pp.38-45
• /
• 2009

First of all, the properties imparted to PET fabrics are resistance to and recovery from creasing or wrinkling when wet or dry; high resistance to stretch in the filament yarns but not in the staple; high abrasion resistance; good texture and appearance; resistance to heat ageing; good chemical resistance and good resistance, behind glass, to sunlight. But, the low moisture regain of PET fabric conduces to static troubles in textile processing. Furthermore, garments made from PET may, during wear, develop electric charges which attract to the fabric particles of soil(dirt, swarf, dust) flying in the air, so that the cuffs of shirts, for example, become soiled quickly and are not easily laundered clean. The sericin constitutes 25$\sim$30％ of silk protein and surrounds the fibroin fiber with sticky layer that supports the formation of a cocoon. The useful biochemical properties of sericin protein are oxidation resistant, antibacterial, UV resistant, hydrophilic property, and good affinity with hydrophobic material. These properties can be used as an improving reagent or a coating agent for natural and synthetic fibers, fabrics, and other intermediate products. The sericin is also applied to cross-link, and can be blended with other materials. In this study, we modified the surface of PET fabric by mixture of sericin finishing agent; sericin, polyuretane binder and 1,2,3,4-butanetetracarboxylic acid (BTCA) cross-link agent. Also, we investigated the finshing effect; moisture regain, stiffness, handle, drape and electrostatic. The moisture regain of PET fabric treated with sericin finishing agent was higher than that of untreated PET fabric. As a result of evaluating influence about handle of PET fabrics treated with sericin finishing agent, it was confirmed that the sericin finishing agent could be use as a linen like finishing agent.

• 폴리머
• /
• 제24권5호
• /
• pp.673-681
• /
• 2000

플라즈마 처리가 나일론 6 직물의 표면 특성과 폴리아닐린/나일론 6 복합직물의 전도도에 미치는 영향을 연구하였다. 산소 플라즈마로 처리한 나일론 6 직물의 표면을 XPS 분석을 통해 확인한 결과 C-O, C-OH 등의 관능기가 도입되었으며, 이는 직물과 폴리아닐린의 결합력을 향상시켜 전기 전도도와 폴리아닐린 부착량을 증가시켰다. 또한 산소 플라즈마로 처리된 폴리아닐린/나일론 6 복합직물은 세탁과 마모에서도 우수한 안정성을 나타내었다. 초음파 처리는 매질에 발생된 cavitation과 진동에 의해 직물 내부로 아닐린을 확산시키는데 효과적이었으며, 이는 폴리아닐린/나일론 6 복합직물의 전기 전도도를 크게 향상시켰다. 아닐린의 농도와 중합욕에 침지 휫수가 증가함에 따라 전기 전도도와 복합직물의 형태안정성에 대한 영향을 살펴보았는데, 단량체 농도는 0.5M 까지는 증가함에 따라 전도도가 향상되었으며, 침지 횟수가 증가함에 따라서도 전도도가 향상되었다.

• 복식문화연구
• /
• 제25권6호
• /
• pp.880-892
• /
• 2017

In this study, the appearance change and the heat moisture transfer properties of knitted fabric by yarn shrinkage were examined to obtain useful data on the development of thermo-sensitive functional materials. Eleven types of knitted fabric were knitted using highly bulky acrylic-blended yarn. After shrinking the specimens using dry heat treatment, the appearance change and thickness were measured. An HEC simulator was adopted for measuring the heat moisture transfer properties of specimens by yarn shrinkage. When holes were arranged vertically in the mesh structure, the specimens with 2,500 and 5,000 holes showed high percent change of hole area, appearance, and thickness. When holes were diagonally arranged in the mesh structure, the percent change of hole area in the specimen with 1,250 holes was larger than the one with 2,500 holes. However, the dimensional stability of the specimen with 2,500 holes was better because of its smaller appearance and thickness change. In the tuck structure, the percent change of hole area in the specimen with 625 and 416 holes was relatively large compared with the appearance and thickness change. Furthermore, the hole size in the tuck structure was smaller than that in the mesh structure but the percent change of hole area was larger. Therefore, it was proved that the tuck structure is more suitable than the mesh structure for developing thermo-sensitive functional materials. Heat moisture transfer property test verified that the change of hole area by yarn shrinkage enabled obtaining the thermal effect due to the distinct temperature difference in the inner layer.

• 한국수소및신에너지학회논문집
• /
• 제20권6호
• /
• pp.499-504
• /
• 2009

The effect of gas diffusion layer (GDL) compression caused by different stack clamping pressures on fuel cell performance was experimentally studied in a miniature 5-cell proton exchange membrane fuel cell (PEMFC) stack. Three stacks with different GDL compressions, 15%, 35% and 50%, were prepared using SGL 10BC carbon fiber felt GDL and Gore 57 series MEA. The PEMFC stack performance and the stack stability were enhanced with increasing stack clamping pressure resulting in the best performance and stability for the stack with higher GDL compressions up to 50%. The excellent performance of the stack with high GDL compression was mainly due to the reduced contact resistance between GDL and bipolar plate in the stack, while reduced gas permeability of the excessively compressed GDL in the stack hardly affected the stack performance. The high stack clamping pressure also resulted in excessive GDL compression under the rib areas of bipolar plate and large GDL intrusion into the channels of the plate, which reduced the by-pass flow in the channels and increase gas pressure drop in the stack. It seems that these phenomena in the highly compressed stack enhance the water management in the stack and lead to the high stack stability.

• Composites Research
• /
• 제33권2호
• /
• pp.61-67
• /
• 2020

프리폼 성형은 섬유 직조물을 이용한 RTM 성형에 있어서 매우 중요한 부분을 차지하고 있다. 탄소 섬유 직조물의 프리폼의 변형은 소재의 강도에 영향을 미치며, 그 중 전단 잠김 각도를 넘어서는 힘이 작용하게 되면 제품에 주름이 발생되어 RTM공정 시 불량발생의 원인이 된다. 그러므로 본 연구에서는 탄소섬유직조물의 전단변형 허용치를 정량화하고 실제 직조물의 성형과 수치모사를 이용하여 성형 특성을 검증하고자 한다. 그 결과 섬유 방향의 설정에 따른 주름의 특성을 확인하고 그 결과를 평가하였다. 앞에 언급한 물성 측정 결과들을 이용하여 수치해석을 수행하였고, 이 결과를 실험 결과와 비교 분석하였다.

• 농업과학연구
• /
• 제35권2호
• /
• pp.147-153
• /
• 2008

본 시험은 상황버섯박의 사료가치를 조사하기 위하여 화학적 성분을 분석하고, 산란계를 이용하여 급여수준(급여사료의 0, 5, 10 및 20%)에 따른 대사율과 혈청 IgG 농도를 조사하였다. 영양적 조성에 있어서는 섬유질성 단미사료 수준 이상의 영양소를 함유하고 있으며, 산란계에 대한 대사율은 대조구에 비하여 상황버섯박 10 및 20% 첨가구가 유의하게 낮은 결과를 보였다(p<0.05). 그리고 혈청 IgG 농도에 있어서는 첨가수준에 따른 유의적인 차이를 발견할 수 없었다. 위 결과로 볼 때 상황버섯박은 섬유질 함량이 높아 단위 동물의 사료로는 제한적 사용이 불가피하며, 버섯의 약리성분은 추출잔류물이라는 특성으로 볼 때 그 작용을 기대하기는 어려울 것으로 판단된다. 또한 상황버섯박은 섬유질 함량이 높은 것으로 보아 단위 동물보다는 반추동물의 사료로 이용하는 것이 유리할 것으로 생각된다.

• Structural Engineering and Mechanics
• /
• 제36권6호
• /
• pp.759-783
• /
• 2010

In this paper, compressive strength of carbon fiber reinforced polymer (CFRP) confined concrete cylinders is formulated using a hybrid method coupling genetic programming (GP) and simulated annealing (SA), called GP/SA, and a robust variant of GP, namely multi expression programming (MEP). Straightforward GP/SA and MEP-based prediction equations are derived for the compressive strength of CFRP-wrapped concrete cylinders. The models are constructed using two sets of predictor variables. The first set comprises diameter of concrete cylinder, unconfined concrete strength, tensile strength of CFRP laminate, and total thickness of CFRP layer. The most widely used parameters of unconfined concrete strength and ultimate confinement pressure are included in the second set. The models are developed based on the experimental results obtained from the literature. To verify the applicability of the proposed models, they are employed to estimate the compressive strength of parts of test results that were not included in the modeling process. A sensitivity analysis is carried out to determine the contributions of the parameters affecting the compressive strength. For more verification, a parametric study is carried out and the trends of the results are confirmed via some previous studies. The GP/SA and MEP models are able to predict the ultimate compressive strength with an acceptable level of accuracy. The proposed models perform superior than several CFRP confinement models found in the literature. The derived models are particularly valuable for pre-design purposes.