• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.69-70
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• 2006

In lithium-ion batteries, separator membrane's, main role is to physically isolate a cathode and an anode while maintaining rapid transport of ionic charge carriers during the passage of electric current. As far as battery safety is concerned, the electrical isolation of electrodes is most crucial since unexpected short-circuits across the membrane induces hot spots where thermal runaway may break out. Internal short-circuits are generally believed to occur by protrusions on the electrode surface either by unavoidable deposits of metallic impurities or by dendritic lithium growth during battery operation. Another cause is shrinkage of the separator membrane when exposed to heat. If separator membrane can be engineered to prevent the internal short-circuit, it will not be difficult to improve lithium-ion batteries' safety. Commonly the separators employed in lithium-ion batteries are made of polyethylene (PE) and/or polypropylene (PP). These materials have terrible limitations in preventing the fore-mentioned internal short-circuit between electrodes due to their poor dimensional stability and mechanical strength. In this study we have developed a novel separator membrane that possesses very high thermal and mechanical stability. The cells employing this separator provided noticeable safety improvement in the various abuse tests.

• Clean Technology
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• v.10 no.4
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• pp.195-201
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• 2004

Cellulase was modified with copolymer with polyethylene(PE)/polypropylene(PP) oxide and maleic anhydride(MA) by maleylation reaction, and modified cellulase was applied to the reprocessing of old newsprint (ONP). Cellulase of modified cellulase enhanced the detachment of ink particles by fibrillation of fiber. The copolymer, which acted as the surfactant formed bubbles and removed the ink particles in the floatation process. Modified cellulase showed the same deinking ability without excess dosage compared with the conventional method. And, it improved the physical properties including tensile strength, brightness, and whiteness compared with the conventional deinking process. The bond between the ink and fiber got stronger as the storage time increased, and it became very difficult to remove the ink particle. But, modified cellulase increased the deinking ability by 41% compared with the conventional process at the experiment of the ONP for 1 year storage time. It removed the yellowing and increased the whiteness and brightness as well as tensile strength and internal bond strength.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.7 no.4
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• pp.221-228
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• 1974

산란직전의 남해산 참굴(Crassostrea gigas)을 산채로 구입하여 통상조건하에서 탈각하여 얻은 굴육질을 polyethylene laminated aluminium pouch (Al+PE : 0.03+0.03mm) 속에 밀봉하여 살균선량(0.2Mrad) 및 멸균선량(2.0Mrad)의 감마선으조 조사하고, 한편, 100ppm의 염소수에 굴육질을 2분간 침지한 후 탈수하여 같은 방법으로 포장하여 35일간의 빙장기간중 세균학적 및 화학적 변화를 대조 굴(조사치 않고 염소수 처리하지 않은)의 경우와 비교하였다. 굴육질의 시초의 총균수는 g당 700-800에 달했고, 0.2 Mrad의 감마선 조사는 빙장 10일째의 저장 기간중의 총 균수를 검측할 수 있는 선 이하로 감소시켰으며 2.0 Mrad 조사는 20일째까지 거의 무균상태를 가져왔다. 감마선 조사는 또한 세균활동을 표시하는 대사물질인 TMA와 TCA soluble nitrogen의 축적을 현저히 억제시켰으며 빙장 후기부터 번식하기 시작하여 총균수가 g당 100,000을 초과케 된 35일째까지도 대조굴의 동일한 총균수 시기에 비하여 이 대사물의 축적억제가 현저했음은 감마선 조사의 효과가 총균수의 양적인 감소뿐만 아니라 동시에 TMA를 생산하고 단백질을 분해할 능력이 있는 세균제거 내지는 번식의 억제라는 선택적인 양면을 가지고 있음을 보여 준다. 염소수 처리한 굴육질의 경우 총균수의 양적인 감소효과는 현저하지 않했는데도 불구하고 감마선 조사 경우처럼 세균대사물질 축적의 철저한 억제를 가져 왔음은 주목할만 하다. 굴육질의 glycogen 함량은 사후 저장 기간 중 쉽사리 감소되지 않했으며 PH 측정으로 본 생굴의 신선도와의 관련성은 희박하며 조사와 염소수 처리굴의 경우 더욱 그러했다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.4
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• pp.269-272
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• 2002

This study was carried out to investigate varietal differences on growth characteristics under the conditions of PE film-mulching and non-mulching in sesame. At maturing stage from 76 to 95 days after sowing, Yangbaeckkae, non-branching plant type, under non-mulching showed larger leaf area index (LAI) than that of film-mulching, while plant height and the number of capsules per plant were similar to those of film-mulching. LAI of Ahnsankkae, branching plant type, under non-mulching was similar to film-mulching, while plant height and the number of capsules per plant were smaller than those of film-mulching. Net assimilation rate (NAR) of two varieties under non-mulching was lower at seedling stage from 25 to 35 days after sowing but higher at flowering stage from 45 to 55 days after sowing. At maturing stage from 66 to 77 days after sowing, NAR and crop growth rate (CGR) of Yangbaeckkae under non-mulching were greater than those of film-mulching, whereas those of Ahnsankkae under non-mulching were lesser than those of film-mulching. Yield under non-mulching was decreased by 7 % in Yangbaeckkae and 33 % in Ahnsankkae compared with that of film-mulching, therefore Yangbaeckkae was more adaptable for non-mulching than Ahnsankkae. Main factors decreasing yield of Yangbaeckkae under non-mulching were small LAI, NAR, and CGR at the stage of young seedling, and small number of capsules at early maturing stage from first flowering to 20 days after first flowering.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.11
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• pp.484-488
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• 1997

Three-dimensional finite element analyses were used to compare the stress distribution and the stability of the fixation among seven different tibial components and to investigate the effect due to implant materials in total knee arthroplasty. The components included an intact tibia(Type I), Cemented Cobalt-Chromium tibial tray implanted with a PMMA cemented Co-Cr stem(Type II), Cemented Co-Cr tibial tray with a uncemented Co-Cr stem(Type III), Cemented Ultra High Molecular Weight Polyethylene (UHMWPE) tibial tray with a cemented UHMWPE stem (Type IV), Cemented UHMWPE tray with a uncemented UHMWPE stem(Type V), Cemented Co-Cr tray without a stem(Type VI), and Cemented UHMWPE tray without a stem(Type VII). Uncemented components were assumed to have complete bony in growth and a rigid state of fixation between component and bone. The interface between bone/cement/component of cemented components was also assumed to be fully bonded. Bi-condylar forces were applied. The results indicated that Uncemented stem components provided lower bone stress shielding and stress concentration. The UHMWPE tray and stem component showed better agreement with the intact tibia than the Co-Cr Alloy tray and stem components. If the implant tray can be fixed firmed without a stem, Cemented PE tray without a stem(Type VII) may be recommended to give the best characteristics in the sense of stress distribution and stability.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.3
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• pp.256-260
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• 2008

This study was conducted to response the photosynthetic rate and anatomical characters in one year ginseng plant against the light transmission ratio (10%, 20% and 30% in natural light) under shading materials by polyethylene (PE) net. The chlorophyll content and the photosynthesis of ginseng according to the light transmissivity showed decreasing trend as the light transmission ratio increased. At the higher light transmission ratio condition, leaves showed the chlorosis due to the physiological disorder, stems formed hypodermis, and phloem development inside the vascular tissue shrunk remarkably. Also, roots showed the epidermis destruction and less cambium development at the higher light intensity. The root weight also decreased as the light transmission ratio increased.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.38 no.4
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• pp.307-316
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• 2002

In order to evaluate the deformation and stiffness of frame structure for fishery, composed of unit platforms which made of two concentric high density polyethylene buoys fixed by clamps and belts and rubber hinge components, under wave, the structural analysis for the square type of the structure was carried out by using finite element methods. The accurate physical properties of rubber hinge components determined by material tests were an important parameter to evaluate more reliable structural stability for the structure. The idealization to beam element with equivalent stiffness and rubber element with linearity for rubber hinges was necessary for the modeling of rubber component which has hyper-elastic characteristics. In addition, it was shown that the structural response of the structure under wave was larger in the hogging condition than that of in the still water or in the sagging condition.

• Journal of Animal Environmental Science
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• v.16 no.2
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• pp.123-128
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• 2010

It is investigated the development of swine liquid manure spreading system for a polyethylene film (PE vinyl) based greenhouse used for planting vegetables. These types of vinylhouses are normally six to eight meters wide; the spread system must be contained and capable of operating within this area. The system we designed for use here consisted of the following parts: 1) a reel for loading the hose, 2) hydraulic motor and cylinder to generate hydraulic pressure, 3) discharge unit, and 4) a frame with a 3-point hiteh link to the tractor. With this system, there are two types of hoses that can be used, a flexible flat hose that can be mounted directly to a tractor or a solid firm round hose which usually separated from the tractor. In either case, the discharge unit remains on the tractor. It is found that by using our spread system overall efficiency was 5 times greater than spreading swine liquid manure manually.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.925-928
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• 2008

Fiber is an important ingredient in strain-hardening cementitious composite (SHCC), which can control fracture of cementitious composite by bridging action. The properties of reinforcing fiber, as tensile strength, aspect ratio and elastic modulus, have great effect on the fracture behavior of SHCC. To apply SHCC to structural member, SHCC must have economical efficiency and workability as well as own excellent tensile performance. For these purposes, four-point bending and direct tensile tests on SHCC with only hybrid synthetic fibers, total fiber volume fraction, $V_f$, is 1.5%, are carried out. The research emphasis is on the mechanical properties of SHCC made in Polyvinyl alcohol (PVA) and Polyethylene (PE) fibers, and how this affects the composite property, and ultimately its strain-hardening performance. Also, effect of hybrid type and water-cement ratio on the behavior of SHCC was evaluated in this paper.

• International Journal of Oral Biology
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• v.36 no.2
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• pp.43-50
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• 2011

Voltage dependent calcium channel (VDCC), one of the most important regulator of $Ca^{2+}$ concentration in neuron, play an essential role in the central processing of nociceptive information. The present study investigated the antinociceptive effects of L, T or N type VDCC blockers on the formalin-induced orofacial inflammatory pain. Experiments were carried out on adult male Sprague-Dawley rats weighing 220-280 g. Anesthetized rats were individually fixed on a stereotaxic frame and a polyethylene (PE) tube was implanted for intracisternal injection. After 72 hours, 5% formalin ($50 \;{\mu}L$) was applied subcutaneously to the vibrissa pad and nociceptive scratching behavior was recorded for nine successive 5 min intervals. VDCC blockers were administered intracisternally 20 minutes prior to subcutaneous injection of formalin into the orofacial area. The intracisternal administration of 350 or $700{\mu}g$ of verapamil, a blocker of L type VDCC, significantly decreased the number of scratches and duration in the behavioral responses produced by formalin injection. Intracisternal administration of 75 or $150 \;{\mu}g$ of mibefradil, a T type VDCC blocker, or 11 or $22\; {\mu}g$ of cilnidipine, a N type VDCC blocker, also produced significant suppression of the number of scratches and duration of scratching in the first and second phase. Neither intracisternal administration of all VDCC blockers nor vehicle did not affect in motor dysfunction. The present results suggest that central VDCCs play an important role in orofacial nociceptive transmission and a targeted inhibition of the VDCCs is a potentially important treatment approach for inflammatory pain originating in the orofacial area.