• 한국염색가공학회지
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• 제25권2호
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• pp.110-117
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• 2013

The purpose of this study is to fabricate the flame retardant polyester fabric by thermal bonding with low melting component of flame retardant bicomponent filament(LMFRPC) and to describe the characteristics of thermal bonded fabrics. The fabrics were prepared with flame retardant polyester filaments(FRP) as warp and blended filaments of FRP and LMFRPC as weft. The LMFRPC have a sheath and a core wherein the core comprises a flame retardant polyester and the sheath comprises a thermoplastic polyester of low-melting point. In this study, we investigated the physical properties, melting behavior of filament, the effect of the component of FRP and LMFRPC on the thermal bonding, mechanical properties. Melting peak of LMFRPC showed the double melting peak. The thermal bonding of the fabric formed at lower melting peak temperature of bicomponent filament of LMFRPC. The optimum thermal bonding conditions for fabrics was applied at about $170^{\circ}C$ for 60 seconds by pin tenter. On the other hand, the tensile strength, elongation, and LOI of the fabric increased with an increasing component of FRP of weft.

• 설비공학논문집
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• 제7권4호
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• pp.577-588
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• 1995

A numerical study is made on the melting process of an unconstrained ice inside an isothermal ice-ball capsule. The unmelted ice core is continuously ascending on account of buoyancy forces. Such a buoyancy-assisted melting is commonly characterized by the existence of a thin liquid film above the ice core. The present study is motivated to present a full-equation-based analysis of the influences of the initial subcooling and the natural convection on the fluid flow associated with the buoyancy-assisted melting. In the light of the solution strategy, the present study is substantially distinguished from the existing works in that the complete set of governing equations in both the melted and unmelted regions are resolved in one domain. Numerical results are obtained by varying the wall temperature and initial temperature. The present results reported the transition of the flow pattern in a spherical capsule, as the wall temperature was increased over the density inversion point. In addition, time wise variation of the shapes for the liquid film and the lower ice surface, the time rate of change in the melt volume fraction and the melting distance at symmetric line is analyzed and is presented.

• 한국식품과학회지
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• 제27권4호
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• pp.483-486
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• 1995

가공적성이 우수한 알코올처리 각시가자미껍질 젤라틴을 식품산업소재로 이용하기 위한 기초자료를 얻을 목적으로 젤라틴농도, pH, 정치온도 및 시간과 같은 겔화조건에 대한 알코올처리 젤라틴의 물리적 특성 및 색조의 변화를 알코올 무처리 젤라틴과 비교하여 검토하였다. 알코올처리 및 무처리 젤라틴이 모두 농도가 증가할수록 겔강도, 졸화온도 및 겔화온도 및 점도 등과 같은 물리적 특성은 증가하였다. 젤라틴 졸의 pH가 에탄올처리한 젤라틴의 경우 6.0일 때, 무처리한 젤라틴의 경우 5.0일 때 겔강도, 졸화온도 및 겔화온도가 가장 높았으나, $pH\;5.0{\sim}8.0$의 범위에서는 거의 차이가 없었고, pH 5.0 이하 및 pH 9.0 이상에서는 급격히 감소하였다. 젤라틴 졸을 겔화시키기 위하여 정치시키는 경우 온도는 낮을수록, 시간은 길수록 겔강도 및 졸화온도는 높았다. 겔화조건을 동일하게 하였을 때 에탄올처리한 젤라틴이 무처리한 젤라틴보다 물리적 특성이 우수하였다.

• Macromolecular Research
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• 제10권3호
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• pp.145-149
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• 2002

Transesterification between poly(trimethylene terephthalate) (PTT) and bisphenol-A-polycarbonate (PC) is studied by differential scanning calorimetry (DSC) and nuclear magnetic resonance (NMR) spectroscopy. When the blend of PTT/PC is annealed at higher temperatures, the samples do not show any melting peak at an initial stage, indicating the samples completely lose their crystallinity due to the formation of random copolymers. However, when the random copolymer is annealed at temperatures lower than the melting temperature of PTT, a melting peak is observed, indicating that the random copolymers are sequentially reordered. The melting point and the heat of fusion of crystals formed from the crystallization-induced sequential reordering depend upon the annealing temperature and time. The average sequence length determined from NMR is increased as the blocks are regenerated.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1991년도 제1차 학술발표초록집
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• pp.29-29
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• 1991

• 한국재료학회:학술대회논문집
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• 한국재료학회 1996년도 재료학회 추계학술발표회
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• pp.38-38
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• 1996

• 월간포장계
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• 통권331호
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• pp.72-75
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• 2020

• 한국생산제조학회지
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• 제18권6호
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• pp.585-589
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• 2009

Extruder is divided to greatly three part at extrusion process. First, by hopper(Hopper) second, barrel(Barrel) with Screw that is point of extruder and third that is raw material supply wealth extrusion into dies(DIES) Part that decide shape of do product greatly divide. Hopper is role that distribute in raw material supply wealth (Feeding zone) of Screw preserving raw material in state of high quality how at extrusion process, and make distributed raw material as Screw in barrel rotates and 3 stage and inflicting heat and pressure raw material melting(Melting) state. And raw material of melting state Screw's measuring stoker(Metering zone) whereabouts anaphora do and product is completed through pipe channel of dies. Dies that is the most important as Screw in extrusion is part that is last part of melting state process of raw material and causes huge effect in quality of product. If more than design of dies happens, manufacture itself of dies is hard, but there are a lot of amount of losses accordingly. In this research, make pipe channel that raw material of melting state flows in dies can present dies basic design method through flow analysis of ideal pipe channel using CFdesign.

• Journal of Astronomy and Space Sciences
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• 제33권4호
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• pp.305-311
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• 2016

The spatial size and variation of Arctic sea ice play an important role in Earth's climate system. These are affected by conditions in the polar atmosphere and Arctic sea temperatures. The Arctic sea ice concentration is calculated from brightness temperature data derived from the Defense Meteorological Satellite program (DMSP) F13 Special Sensor Microwave/Imagers (SSMI) and the DMSP F17 Special Sensor Microwave Imager/Sounder (SSMIS) sensors. Many previous studies point to significant reductions in sea ice and their causes. We investigated the variability of Arctic sea ice using the daily sea ice concentration data from passive microwave observations to identify the sea ice melting regions near the Arctic polar ice cap. We discovered the abnormal melting of the Arctic sea ice near the North Pole during the summer and the winter. This phenomenon is hard to explain only surface air temperature or solar heating as suggested by recent studies. We propose a hypothesis explaining this phenomenon. The heat from the deep sea in Arctic Ocean ridges and/or the hydrothermal vents might be contributing to the melting of Arctic sea ice. This hypothesis could be verified by the observation of warm water column structure below the melting or thinning arctic sea ice through the project such as Coriolis dataset for reanalysis (CORA).

• 열처리공학회지
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• 제35권1호
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• pp.1-7
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• 2022

In this study, dissolution and melting phenomenon of the Al₂Cu was studied for the high-strength Al-Si-Cu aluminum alloy in automobile component. The Solution heat treatment was performed at 480℃ and 510℃ for 4hours. Microstructure analysis of the specimen was performed using the optical micrograph and scanning electron microscope for qualitative and quantitative analysis of various phases, the chemical composition of secondary phases was achieved by energy dispersive spectroscopy (EDS) and electron probe micro analysis (EPMA). As a result of the electron probe micro analysis, a plate like Al₂Cu phase was observed, and eutectic Si phase was observed of a coarsen plate shape. At a temperature of 510, necking phenomenon occurs in a specific part of plate like Al₂Cu, and it is segmented and dissolved in the Al matrix. When the temperature of the alloy exceeds the melting point of Al₂Cu, incipient melting occurs at the grain boundary of undissolved Cu particles