• Journal of Nutrition and Health
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• 제47권6호
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• pp.484-488
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• 2014

Purpose: This study investigated the question of whether the addition of natural ingredients (pear fermented solution, celery powder, vitamin C) in curing agents may influence antioxidant activities and nutritional characteristics of smoked duck. Methods: Smoked duck samples with general or natural curing agent containing three additive ingredients were examined to determine total polyphenol contents, antioxidant activities, pH, TBARS, and food additives residue (nitrite ion, antioxidant, sodium glutamate). Results: Smoked duck with natural curing agent showed a higher level of total polyphenol content and antioxidant activities than smoked duck using general curing agent (p < 0.05). The pH and TBARS of smoked duck were significantly decreased by the addition of natural curing ingredients compared to those of smoked duck using general curing agent (p < 0.05). The residues of food additives were not detected in smoked duck using natural curing agent. Conclusion: Findings suggest that the addition of pear fermented solution, celery powder, and vitamin C in natural duck curing agent may improve the antioxidant activities and nutritional characteristics of smoked duck and provides health benefits.

• Elastomers and Composites
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• 제19권3호
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• pp.163-177
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• 1984

The effect of curing temperature increase and sulfur amount added were studied with natural and synthetic rubbers. Also, the effects of TMTD, MBTS and mixture of zinc soaps of high molecular fatty acids added to natural rubber were investigated respectively. The experimental results showed that, in the case of the conventional curing ($145^{\circ}C$), natural rubber, compared with synthetic rubber, gave higher values in elongation, tensile strength, cure rate, and lower values in modulus change. But, at high temperature curing ($180^{\circ}C$), natural rubber showed faster reversion rate, and higher heat build-up compared to synthetic rubber, than in the conventional curing. Also, natural rubber produced at high temperature showed severe degradation in hardness and tensile strength before heat-aging as well as in hardness, modulus and tensile strength after heat-aging. Improved reversion effect was obtained with natural rubber either by blending mixture of zinc soaps of high molecular acids or by applying semi-efficient vulcanization system.

• 한국도로학회논문집
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• 제20권4호
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• pp.35-46
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• 2018

PURPOSES : The purpose of this study is to compare the lane curing time of natural drying and a lane drying device when painting lines on a highway. METHODS : The painting process was carried out in July 2015 and September 2015, respectively, for the Gimcheon IC - Gimcheon JC. After the painting, measurements were obtained three times at six measurement points located at 20 m intervals on the shoulder line and the dividing line. The curing time was measured for natural drying and drying using a lane drying device, and compared for different pavement types (asphalt, concrete) and paint types (waterborne paint, methyl methacrylate paint). RESULTS : The results of the lane curing time comparison on the highway are as follows. The combination of asphalt and methyl methacrylate paint cured more rapidly during both the natural drying and drying using the lane drying device. Finally, it was cured at least 32.2% and 40.7% faster when using a drying device than in natural drying. CONCLUSIONS : The comparison of lane curing time of the highway showed that the combination of asphalt and methyl methacrylate paint cured more rapidly when using both natural drying and a lane drying device.

• Advances in concrete construction
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• 제6권1호
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• pp.69-85
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• 2018

In order to provide sufficient stability and resistance against bleeding and segregation during transportation and placing, mineral admixtures are often used in self-compacting concrete mixes (SCC). These fine materials also contribute to reducing the construction cost and the consumption of natural resources. Many studies have confirmed the benefits of these mineral admixtures on properties of SCC in standard curing conditions. However, there are few published reports regarding their effects at elevated curing temperatures. The main objective of this study is to investigate the effect of three different mineral admixtures namely limestone powder (LP), granulated blast furnace slag (GS) and natural pozzolana (PZ) on mechanical properties and porosity of SCC when exposed to different curing temperatures (20, 40, 60 and $80^{\circ}C$). The level of substitution of cement by mineral admixture was fixed at 15%. The results showed that increasing curing temperature causes an improvement in performance at an early age without penalizing its long-term properties. However the temperature of $40^{\circ}C$ is considered the optimal curing temperature to make economical and high performance SCC. On the other hand, GS is the most suitable mineral admixture for SCC under elevated curing temperature.

• Advances in materials Research
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• 제12권1호
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• pp.1-13
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• 2023

The combination of cobalt ferrite and natural rubber has a potential to enhance the functional properties of rubber ferrite composites available on the market. In this study, cobalt ferrite was synthesized by the sol-gel method with tapioca starch as a cheating agent and then incorporated into natural rubber using an internal mixer. The curing characteristics, magnetic hysteresis, complex permeability, and permittivity of the rubber ferrite composites were studied as a function of the loading from 0 to 25 phr. The cure time and scorch time tended to reduce with the addition of non-reinforced cobalt ferrite fillers. The remanent and saturation magnetizations were linearly proportional to the cobalt ferrite loading, consistent with the rule of mixture. On the other hand, the increase in cobalt ferrite loading from 5 to 25 phr slightly affected the coercive field and the complex permeability. Using the maximum loading of 25 phr, both real and imaginary parts of the permittivity were significantly raised and reduced with the frequency in the 10-300 MHz range.

• 자연과학논문집
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• 제8권2호
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• pp.21-26
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• 1996

시중에서 판매하는 중국산 옻칠을 그대로 혹은 유기용매에 녹는 부분과 녹지 않는 부분으로 분리하고 각각의 경화현상을 연구하였다. 그대로 사용하는 경우에는 상온에서 수분이 포화된 상태에서 경화를 관찰하였으며 유기용매로 분리한 부분의 경화는 섭씨 $100^{\circ}C$와 $150^{\circ}C$에서 경화를 관찰하였다. 서로 다른 방법으로 얻어낸 도막의 성질을 서로 비교하였으며 옻 중 유기용매에 녹는 부분과 1,6-diisocyanohexane, toluendiisocyanate(TDI)를 공중합하였을 때 얻어지는 도막과 다른 도막과의 성질로 비교하였다. 가열하여 형성된 도막은 매우 깨어지는 성질(취성)이 매우 높았으며 자연상태로 경화된 도막에 비하여 친수성이 낮았다. Diisocyanate를 사용하지 않은 경우에는 경화에 산소가 필수적이어서 오랜 시간이 지나도 내부는 경화가 되지 않았다.

• KIEAE Journal
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• 제7권4호
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• pp.127-133
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• 2007

As a fundamental study on the corrosion resistance of reinforced concrete structures using Natural Inorganic Minerals exposed to carbonation environment, The test specimens were concrete(W/C=60%) with Natural Inorganic Minerals content of 0%, 10%. Accelerated carbonation and autoclave corrosion accelerated curing were then conducted with them. The corrosion resistance of steel in concrete with Natural Inorganic Minerals content of 0%, 10% was examined by corrosion form, half-cell potential, polarization resistance, corrosion area and weight loss after 24 hours of autoclave corrosion accelerated curing.The results of the study showed that as for steel in concrete with Natural Inorganic Minerals content of 10%, the corrosion resistance was more excellent than steel in concrete with Natural Inorganic Minerals content of 0%.

• 대한기계학회논문집A
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• 제21권3호
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• pp.378-384
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• 1997

In curing process of tire, contact and slip occurs between green tire and curing bladder. The curing process is a critical step in the manufacture of tires. In this investigation, curing bladder shaping is examined using a finite element method. Specifically, a finite element model between the inner part of green tire and the outer part of curing bladder is generated using contact element and curing bladder is generated using incompressible element. Numerical analysis are performed on two different bladder types, different overall outer diameters of curing bladder and different heights of curing bladder. Numerical results show that contact pressure is increased by using toroidal type of curing bladder, increasing overall diameter and increasing height of curing bladder. To obtain natural equilibrium carcass line, there is a requirement in increasing contact pressure of the section between side and bead.

• 한국축산식품학회지
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• 제43권4호
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• pp.580-593
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• 2023

The purpose of this study was to analyze whether seawater has positive effects on appearance characteristics, such as CIE a^*, and to determine the gas composition concentration that is suitable for maintaining it. Pork hind meat was cured with four types of curing agent for 5 d at 4℃. The different curing agents comprised the control salt, control nitrite pickling salt (CN), treatment brine, and treatment bittern (BT). The cured hams were cooked at 65℃ for 4 h and packaged at O₂:N₂ gas ratios of 7:3, 8:2, and 9:1 for 3 wk. The physicochemical properties were assessed immediately after heating the sample, and the color properties were measured after a 3 wk storage period. Based on the correlation results of the physicochemical properties, BT had a higher curing and cooking yield than the other treatments, owing to its high salinity. Results of color properties for BT (7:3) and CN (8:2) showed similar color CIE L^*, CIE a^* chroma, and hue angle values. Therefore, BT can be said to be a sous-vide curing agent suitable for preserving the color of ham, and a high nitrogen concentration of 30% helps to maintain the appearance of seawater sous-vide ham.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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• pp.1013-1016
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• 2003

This paper is to evaluate practically the techniques and materials of repair for RC elements with fire damages as well as to investigate the structural behavior of RC beams according to pre- or post-repair after fire-damages. For this purpose, normal concrete flexural specimens were exposed to high temperatures by the ISO 834 specification. After natural cooling and post-fire-curing in a natural environment for 2 months, the specimens were repaired with polymer cement mortar for 1 month curing.