• 한국추진공학회지
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• 제9권2호
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• pp.1-8
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• 2005

가스발생기용 저 연소속도 HTPB/AP계 고체추진제의 조성에서 냉각제인 Oxamide와 Melamine이 추진제의 연소특성에 미치는 효과를 고찰하였다. 냉각제의 함량을 증가시키면 연소속도와 화염온도가 낮아지고, 두 냉각제의 화염온도에 미치는 영향은 유사하였다. 그러나 냉각제의 열분해 특성 차이로 인하여 Melamine 추진제에서는 비정상적으로 $200{\mu}m$ AP의 일부를 $6{\mu}m$ AP로 대체하면 연소속도가 오히려 감소하는 현상을 나타내었다.

• Bulletin of the Korean Chemical Society
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• 제31권5호
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• pp.1119-1120
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• 2010

• 접착 및 계면
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• 제10권2호
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• pp.84-89
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• 2009

The objective of this research was to investigate the curing behavior and adhesion performance of urea-melamine-formaldehyde (UMF) resin for the four types of UMF-1, UMF-2, UMF-3, and UMF-4 which synthesized by the staged addition of melamine. Also, various network structures of these resin types were discussed based on their different curing behavior and adhesion performance. The curing behavior was evaluated by DMTA and thermal stability was checked by TGA. Adhesion performance was evaluated by dry and wet shear strengths and the pH value of each cured resin was checked to see its effect on the adhesion performance. The results indicated that the UMF-1 resin type by the addition of melamine initially with the urea and formaldehyde at the same F/(U+M) rate showed the lowest thermal stability, rigidity (${\Delta}E^{\prime}$), temperature of tan ${\delta}$ maximum ($T_{tan}\;_{\delta}$), and wet shear strength, and pH value of cured resin. In wet shear strength, however, the UMF-4 resin type appears to be slightly higher than UMF-1 resin type.

• Journal of the Korean Wood Science and Technology
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• 제30권2호
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• pp.165-171
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• 2002

본 연구는 마루판의 천연무늬단판 접착에 이용되고 있는 요소-멜라민 접착제의 수지조성에 따른 접착성능 및 포름알데히드 방출량의 변화를 알아보고자 하였다. 요소에 멜라민에 대한 포름알데히드의 몰비 1.0, 1.1, 1.2, 1.4를 기준으로 제조된 접착제로 마루판용 합판과 섬유판에 천연무늬단판을 접착한 목질마루판에 의해 시험을 실시하였다. 그 결과는 화학양론적으로 멜라민-요소와 포름알데히드간의 비율이 적정한 조건에서 반응이 충분히 일어난 경우에 상태접착력, 준내수접착력, 포름알데히드 방출량 등이 가장 양호하게 나타났다. 복합마루판의 평면인장강도는 각 몰비에서 14 kgf/cm²를 상회하였으며, 포름알데히드 방출량은 1.0몰비에서 9.53 mg/L로 가장 낮게 나타났다. 합판마루판의 평면인장 접착력 시험에서는 1.4몰비에서 14.02 kgf/cm²로 가장 높은 값을 보였다. 합판마루판의 포름알데히드 방출량 조사에서도 1.0목비에서 0.26 mg/L로 가장 낮게 나타났다.

• 한국식품위생안전성학회지
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• 제25권2호
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• pp.180-184
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• 2010

본 연구는 식품안전 사건에 따른 소비자들의 구매행동 변화를 조사할 목적으로 2008년 발생한 멜라민사건을 예로 하여, 사건 전후의 주부들의 의식 및 행동 변화를 조사하기 위하여 2009년 3월 전라북도 군산지역에 거주하고 있는 주부 565명을 대상으로 설문조사를 실시하였다. 그 결과 우리나라 식품안전 수준에 대해서 52.3%가 불만족스러워 하는 것으로 나타났으며, 멜라민 사건 발생 후 어느 정도의 시간이 경과하였지만 조사대상자의 74.6%는 여전히 멜라민을 독성이 높은 물질로 인식하고 있는 것으로 나타났다. 멜라민 관련식품의 구매수준을 5점 척도에 의해, 사건 발생 전, 발생기간, 사건 종료 후(즉, 조사시점)의 수준을 분석한 결과, 각각 $2.47{\pm}0.97$, $1.80{\pm}0.92$, $1.62{\pm}0.92$(p<0.001)로, 사건발생 후 어느 정도의 시간이 경과하였음에도 구매수준은 더욱 낮아 진 것으로 나타났다. 독성 인식수준에 따른 구매수준에 변화에 있어서는 독성수준이 낮다고 인식하고 있는 사람은 관련제품 구매에 큰 변화가 없었으나, 높다고 인식하고 있는 사람은 구매수준에 있어 더 많은 감소를 나타냈다(p<0.05). 식품안전인식 수준에 따른 구매수준에 변화에 있어서도 국내 식품안전수준이 안전하다고 인식하고 있는 사람은 여전히 관련제품의 구매에 큰 변화가 없는 것으로 나타났다(p<0.05). 결론적으로 식품안전 수준에 대한 사전인식과 해당 유해물질에 대한 정확한 정보가 사건발생후의 식품구매행동에 많은 영향을 미친다고 볼 수 있으며, 소비자와의 체계적이고 다각적인 방향으로의 위해정보교류의 필요성이 한층 커지고 있다고 볼 수 있다.

• 폴리머
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• 제32권2호
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• pp.125-130
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• 2008

A commercial cyclic diphosphonate ester (TPMP) and melamine (MA) was combined and added to polyamide 6 (PA6) to prepare the fire retardant PA6. An increase of the oxygen index to 28.6 as well as an improvement of the UL-94 classification to V-0 rating was observed. Cone measurements explained the rate of heat release (RHR) decreased and TGA showed the early decomposition and high solid residue due to co-addition of TPMP and MA, suggesting the occurrence of synergistic effect of TPMP and MA on fire resistance of PA6. The morphology of the char developed during combust ion showed the appearance of thick, intumescent cells on the surface of retardant PA6, which protects the underlying material from the action of the heat flux or flame and limits the diffusion of combustible volatile products towards the flame and oxygen.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권3호
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• pp.65-72
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• 2013

Adsorption of melamine was examined using columns packed with granular activated carbon (GAC). Raw GAC was sieved with 20, 40, 60 and 80 mesh to determine the influence of adsorbent particle size on reaction and diffusion. The mass ratio of the adsorption capacity of GAC for melamine ranged from 9.19 to 11.06%, and adsorption rates increased with decreasing particle size within this range. Rate constants between 3.295 ~ 4.799 $min^{-1}$ were obtained using a pseudofirst-order equation that was used to determine adsorption kinetics. A surface diffusion model was adapted to take into account the unsteady-state equation of a spherical adsorbent by converting the surface concentration from a constant to a variable governed by a dispersion equation. The calculated values were fit with the experimental results by using the diffusion coefficients as regression parameters. The modified equation exhibited a more precise agreement with respect to the sum of the absolute error (SAE).

• Journal of the Korean Wood Science and Technology
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• 제38권2호
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• pp.117-123
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• 2010

The objective of this research was executed to investigate the effect of molar ratio of formaldehyde to urea and melamine (F/(U+M)) of urea-melamine-formaldehyde (UMF) resin on bonding high and low moisture content veneers. For that purpose, UMF resin types with 5 different F/(U+M) molar ratios (1.45, 1.65, 1.85, 2.05, and 2.25) synthesized were used in present study. First, their curing behavior was evaluated by differential scanning calorimetry. Second, their adhesion performance in bonding high and low moisture content veneers was evaluated by probe tack and dry and wet shear strength tests. Curing temperature and reaction enthalpy decreased with the increase of F/(U+M) molar ratio. And the dry and wet shear strengthsof plywood manufactured from low moisture content veneers were higher than thoseof plywood manufactured from high moisture content veneers. Also, the maximum initial tack force on the low moisture content veneer was higher than that on the high moisture content veneer.

• 동력기계공학회지
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• 제20권5호
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• pp.20-28
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• 2016

This study has developed an organic/inorganic hybrid solution by addition of $SiO_2$ polysilicate and Melamine to the urethane. The three types of cold rolled steel were evaluated a corrosion resistance properties by using these solutions. The urethane solution(U) and the urethane solution with $SiO_2$ polysilicate($US_7$) were generate a lot of corrosion. The urethane solution with $SiO_2$ polysilicate and melamine($US_7M_3$) was excellent in corrosion resistance, regardless of the steel type. In addition, corrosion resistance has been shown to depend on the tensile strength. The appearance of coating by U and $US_7$ solution is bumpy surface, and were a lot of fine defects. $US_7M_3$ solution is made a sophisticated molecular cross-linking structure inside the coating, it was a slick surface. Other characteristics are exhibited the excellent property for all solutions.

• 한국가구학회지
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• 제14권2호
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• pp.21-29
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• 2003

This study was carried out to investigate characteristics of plywood overlaid with softwood veneers densified by resin impregnation and compression. The resin impregnability of Korean pine veneer under atmospheric pressure soaking was greater than that of larch, and impregnability of melamine resin was slightly greater than phenolic resin. It was suggested that resin impregnation ratio was affected by density and thickness of veneer. The largest melamine resin impregnation ratio of 50.7% was obtained with 1.26mm thick Korean pine veneer, and the lowest phenolic resin impregnation ratio of 11.7% with 3.41mm thick larch veneer. Therefore, it was suggested that the vacuum-pres sure-soak treatment is required at thick larch veneer. In densifying resin-impregnated veneers, densification ratio from 13.4 to 31.2% was obtained by high pressure from 15.6 to $20.8kgf/cm^2$. Impregnation of melamine resin also showed relatively greater at densification than that of phenolic resin. So it showed the degree of densification of about 20% or greater. It was seemed that adhesive bonding strength of plywood(base panel) which was directly pressed and overlaid with resin-impregnated veneer was affected by resin tackiness after resin impregnation followed by semi-drying. In laboratory scale, melamine resin impregnation was more favorable for the development of adhesive bonding strength owing to moisture control.