• 한국의류산업학회지
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• 제20권5호
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• pp.569-582
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• 2018

The purpose of this study is to verify the impact protection performance and to evaluate the activity, design, fit, and pad characteristics of the fall impact protection clothing for elderly women. The protective clothing was designed as pants type and underwear type, and an impact protection pad in the form of a tightly connected regular hexagon piece was inserted in the hip and hip joints. The pad was made of two kinds of foam single pad and foam and gel combination pad so that they could be inserted into pants type and underwear type, respectively. The results of the shock absorption performance of the fall impact protective clothing showed that when the impact force of 4601N was applied to the pants type protective clothing, the impact force was reduced by 29% in the foam pad type and 26% in the gel and foam pad type. When the force of 5113N was applied to the underwear type, it decreased by 40% in the foam pad type and by 34% in the gel and foam pad type. As a result of wearing evaluation of subject group, it was found that fit and activity of underwear type was better than that of pants type. Foam pad type was evaluated to be lighter than gel and foam pad type in both the subject and the expert group and the gel and foam pad was evaluated to be more flexible in the expert group.

• 한국의류산업학회지
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• 제20권4호
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• pp.422-428
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• 2018

In this study, we developed honeycomb pads using foam and polymer gel and verified the impact protection performance of pads for the development of a fall protection pants for elderly women aged 65 and over who have a high risk of fracture due to falls. The results are as follows; In the first experiment, the impact protection performance was evaluated for four honeycomb pad samples (CR foam, EPDM foam, hardness 15 polymer gel, and hardness 30 polymer gel) manufactured to a thickness of 5 mm using a single material. When the force of about 10757N was applied to the specimens, all four pads reduced the impact force to 3100N or less. Polymer gels showed better protection than foam materials. In the second experiment, the thickness of the protective pad was set to 8 mm in order to improve the shock absorbing performance of the protective pad. As a result of evaluating the impact protection performance of the foam single pad and foam gel composite pad, the impact absorbing performance of the foam single pad was better. Finally, four kinds of protection pads were made by assigning the foam single pad and the foam gel composite pad to pants type and underwear type respectively. The pad thickness of the main protection area was set to 8 mm to enhance the protection, and gradually decreased to 5mm and 3mm toward the edge to improve the appearance and fit.

• 한국방사선학회논문지
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• 제17권6호
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• pp.957-964
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• 2023

본 연구는 시중에 판매되고 있는 다양한 성분과 제형의 손 소독제들을 전파 매질로 활용하여 초음파 검사를 진행한 후 획득한 영상을 평가·비교하여 기존의 초음파 젤의 대체 가능성을 확인하고자 하였다. 연구 방법으로는 점도가 낮은 liquid type을 제외한 gel type, cream type, foam type의 제형의 제품들을 선정해 에탄올 62% gel type 1개와 cream type 1개, 벤잘코늄 염화물 0.066% cream type 1개와 foam type 1개를 각각 초음파 매질로 사용하여, 축방향 & 측방향 분해능, 투과심도, probe와 phantom 사이의 공기층 형성유무에 관한 영상 평가를 진행하였다. 그 결과, 축방향 & 측방향 분해능 평가와 투과심도 평가에서 4개 실험군 모두 평가 기준에 적합한 결과가 나왔다. 그러나 foam type의 경우 분해능과 투과심도의 평가 기준에는 적합하지만 영상 평가 시 관찰 중심부를 제외한 양 측면부에서 어두운 음영으로 나타났다. 해당 실험을 통해 foam type을 제외한 나머지 3종의 손 소독제는 초음파 젤을 대체할 수 있을 것으로 사료된다.

• 한국분말재료학회지
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• 제18권2호
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• pp.129-134
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• 2011

Herein, macroporous carbon materials were readily prepared by carbonization of cured body of resorcinol and formaldehyde using poly(methyl methacrylate) colloid microspheres which were employed as the template in the gelation of resorcinol with formaldehyde. The gel in the water was solvent exchanged with methanol and the wet gel was dried. After carbonization of the template-gel composite at $800^{\circ}C$, it was found that pores were left corresponding to the size of the template, yielding carbon materials with a fine porous structure with enlarged surface area and significant porosity. Properties of the carbon foams including the structure, morphology, thermal stability, and porosity were investigated. Finally, it was concluded that the method using polymer colloids as the template provided a facile route to prepare carbon foams.

• 폴리머
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• 제26권4호
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• pp.508-515
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• 2002

폴리프로필렌 (PP)의 전자선 가교 발포 공정에 있어서 전자선 조사량과 발포재료의 분자량 및 다양한 발포 공정이 발포체의 구조에 미치는 영향에 관해 연구하였다. 가교된 PP의 겔분율은 3.2 Mrad의 전자선 조사량에서 48%로 가장 높게 나타났고 발포체의 셀 균일성과 열 안정성에 큰 영향을 나타내었다. 3.2 Mrad 이상의 전자선 조사량에서 겔분율이 48%에서 더 이상 증가하지 않았으며, 발포체 구조 향상에도 더 이상 영향을 미치지 못하였다. 분자량이 증가할수록 높은 전단 점도와 겔분율을 나타내며 보다 균일하고 미세한 셀 구조를 형성하고, 열안정성이 높은 발포체를 형성하였다.

• 폴리머
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• 제26권1호
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• pp.61-70
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• 2002

단일 중합체 폴리프로필렌(PP) 수지가 가지는 분자량 특성과 유변 특성이, 회분식 가교 발포 공정을 통해 생산된 발포체 구조 변화에 미치는 영향을 연구하였다. 또한, 전자선 조사 가교가 PP 발포체에 미치는 영향도 연구하였다. 분자량 증가에 따른 저장 모듈러스(G'), 손실 모듈러스(G"), 제로 전단 점도($\eta_O$) 및 완화시간($\lambda$) 등의 유변 물성 값은 증가하였고, 이러한 유변 물성의 증가는 발포체 구조의 안정성에 직접적인 영향을 미쳤다. 전자선 조사량에 따른 PP의 겔분율은 3.2 Mrad의 전자선 조사량에서 크게 증가하며, 발포체의 안정성을 크게 향상시켰고, 그 이상의 전자선 조사량에서는 겔분율은 다시 감소하였고, 발포체 구조 또한 불안정해졌다.정해졌다.

• 환경생물
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• 제31권4호
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• pp.302-307
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• 2013

Microbial fermented cellulose gel, citrus gel (CG), was successfully fabricated to porous foam by radiation treatment and freeze drying. The chemically induced radiation was used to create highly porous foam and further freeze drying of the CG produced tough foams with interconnected open pores for use in tissue engineering. The microstructure of the CG foam was controlled by varying the irradiation dose and quenching temperature with pore size ranging from several microns to a few hundred microns. Tensile strength and Gurley value of the CG foam were influenced by irradiation dose. These radiation induced CG foams are promising scaffolds for tissue engineering.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2007년도 제34회 KOSCO SYMPOSIUM 논문집
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• pp.37-44
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• 2007

A nickel foam, one of metal foams was seleced as a catalyst support instead of conventional ceramic materials. $Al_2O_3$ was coated on the surface of nickel foam to increase the surface area. $Al_2O_3$ coating process was based on sol-gel process. SEM image was obtained and $Al_2O_3$ coverage was confirmed. Combustion experiments were carried out using SUS combustor and $H_2$/air mixture. Temperatures were measured with different equivalence ratios and $H_2$ flow rates. $H_2$ conversion rates were calculated by the analysis of product gas using gas chromatography. Catalytic combustion of $H_2$ was complete and stable with Pt/$Al_2O_3$ coated nickel foam and influences of water vapor were confirmed during the beginning of combustion.

• 한국식품과학회지
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• 제30권4호
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• pp.902-907
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• 1998

본 연구에서는 세포 고정화를 위해 기존의 고정화 방법의 단점을 보완하기 위하여 새롭게 개발된 GFM 시스템에 Paracoccus denitrificans를 고정화하여 물속의 nitrate를 분해하는데 적용하였다. 고정화 조건으로써 스폰지 구멍의 크기 20 P.P.I. (pore per inch)와 겔로서 alginate가 이미 최적의 조건으로서 선택되었다. 고정화 세포의 연속 nitrate 분해능력을 air-lift reactor내에서 측정한 결과, 물속의 nitrate함량이 증가함에 따라 분해능력이 증가함을 나타내었다. 또한 연속운전에서 본 시스템은 기존의 고정화시스템인 bead 겔포괄법과 비교할 때 $1.2{\sim}2.1$배 정도 분해능력이 향상되었다. 최고 nitrate 분해속도는 buffer를 함유한 medium에 있어서 177 mg/L h이었으나 buffer를 첨가하지 않은 경우에 있어서는 33 mg/L h이었다. 또한 저장안정성을 측정한 결과, $5^{\circ}C$에 저장하였을 때 분해능력은 16주간 거의 변화가 없었으며 고정화하지 않은 자유세포나 bead에 고정화된 세포에 비하여 저장안정성이 두드러지게 뛰어났음을 알 수 있었다.

• 한국미생물·생명공학회지
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• 제22권6호
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• pp.646-650
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• 1994

Aspergillus terreus NRRL 1960 was immobilized on various alginate gel beads, Celites, and polyurethane foam cubes, and the comparisons were made for the production of itaconic acid according to the types and sizes of each carrier. The levels of itaconic acid produced from Ca- alginate and Sr-alginate were similar, and the addition of bentonite to Ca- and Sr-alginate resulted in an increase of itaconic acid. The addition of 1.67% bentonite and 0.33% starch to Sr-alginate (SABS bead) produced higher level of itaconic acid (11.59 g/1) than other gel beads. A decrease in the size of Celite increased the itaconic acid production, and the smallest size of Celites, R- 634, produced 6.37 g/l of itaconic acid. Among various types of polyurethane foam cubes, HR 08 (2X2X2 cm) produced about 19 g/l of itaconic acid, which was more efficient than other carriers. In a repeated batch culture using immobilized cells on polyurethane foam cubes (HR 08, 2X2X2 cm), the stability of itaconic acid production was maintained up to 4 batches. Also, the possibility of itaconic acid production by continuous culture was shown in a packed-bed reactor.