• Food Science and Preservation
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• v.22 no.4
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• pp.505-511
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• 2015

This study was performed to investigate the effect of drying temperature on the quality characteristics and antioxidant activity of blueberry. Blueberries were dried at different times and temperatures, including A ($40^{\circ}C$, 72 hr), B ($40^{\circ}C$, 48 h and $50^{\circ}C$, 24 hr), C ($50^{\circ}C$, 72 hr), and D ($60^{\circ}C$, 72 hr). The yield and pH ranges of blueberry were determined to be 17.73~31.17% and 3.20~3.25, respectively. The yield rate of A treatments, soluble solid of D treatments, was the highest. The yield rate and soluble content was the highest in the treatment of A and D, respectively. The moisture content and water activity were significantly decreased with the increase in drying temperature (p<0.05). The L value of A treatment, and a and b values of D treatment were the greatest. In the analysis of texture analyzer, hardness, springiness, cohesiveness, gummiess and chewiness were significantly increased with the increase in drying temperature (p<0.05). In the sensory evaluation of blueberry, the appearance and color were the highest in the A treatment. The moisture, texture and taste was highest in the B treatment. The overall acceptability was in the order of B > A > C >D. The total polyphenol content and DPPH radical-scavenging activity were 9.21~13.05 mg/GAEg and 61.90~81.42%, respectively, which were significantly decreased with the increase in drying temperature (p<0.05). Therefore, the optimum time and temperature for blueberry drying was founded to be B treatment ($40^{\circ}C$, 48 hr and $50^{\circ}C$, 24 hr) among other treatments.

• Composites Research
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• v.13 no.3
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• pp.48-57
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• 2000

Fracture analysis of coating cracking on a substrate system described in a companion paper was applied and verified by four-point bending tests. The multiple cracking of coating was predicted using a fracture mechanics approach. The strain energy release rate (G) due to the formation of a new crack in a coating was obtained. A crack density vs. strain data of metallic and polymeric substrate was used to get the in-situ fracture toughness of coating with respect to various baking time and temperature. The $G_c$ was decreased as the baking temperature and time was increased. This paper gave insight about usefulness of four-point bending test for fracture toughness evaluation of coating and it gave a new method for in-situ coating toughness.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2017.05a
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• pp.137-137
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• 2017

Al-Mg 합금은 비중이 적고 강도가 우수하기 때문에 해양 환경에서 구조용 재료로 많이 사용되고 있으며, 특히 선박용 재료로 사용될 경우 선체의 중량을 줄일 수 있어 연료비가 절감되며 선속의 고속화가 가능하다. 그러나 해양환경에서의 재료 특성에 관한 지식 및 관련 기술 부족으로 알루미늄 선박 건조는 활성화 되지 못하고 있는 실정이다. 알루미늄 합금은 공기 중에서는 우수한 내식성을 지니는 것으로 알려져 있으나 해수환경에서는 염소이온에 의한 부동태 피막 파괴로 인해 내식성이 저하되며 공식 및 응력부식균열 등에 의한 손상이 발생할 수 있다. 특히 용접부의 경우, 모재에 비해 부식손상에 취약하며 기공과 같은 용접 결함을 포함하고 있어 구조물 파괴의 시발점이 될 수 있으므로 선박 및 구조물 건조시 대비가 필요하다. 그러나 이에 관한 충분한 연구가 이루어지지 않아 국내 중소형 조선소의 경우 알루미늄 선박 건조에 어려움을 겪는 경우가 많다. 따라서 본 연구에서는 선박 건조 및 해양 구조물에 널리 사용되는 Al 5083-H321 합금 용접부에 대하여 해수 내 부식 특성을 연구하고자 한다. 부식특성 파악을 위한 전기화학적 실험에 앞서 화학적 에칭을 통해 미세부위별 실험을 수행하였다. 기준전극은 은/염화은 전극을 대극은 백금전극을 사용하였으며, 타펠 분석을 위한 분극실험은 OCP를 기준으로 -0.25 ~ +0.25 V까지 실시하였고 양극분극실험은 OCP ~ +3.0 V까지 실시하였다. 양극분극 실험 후 부식된 표면은 주사전자현미경과 3D 분석을 통해 용접부 조직에 따른 전기화학적 특성을 관찰하였다.

• Microbiology and Biotechnology Letters
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• v.1 no.1
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• pp.59-65
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• 1973

The details of design procedure, practically used for the construction of fluidized bed dryer system of the Super Cereal Plant of 250, y capacity were presented. The plant was in its entirety designed and constructed solely by domestic engineering potenality with local construction materials. In the drying process, the water content of cooked kernel of wheat is reduced from about 23% to about 14% and the conversion of starch contained in the endosperm to ${\alpha}$-starch is to be completed by contacting with hot combustion gas of kerosene at about 90-130$^{\circ}C$.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2001.04a
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• pp.158-158
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• 2001

산업용 포장재의 주원료로서 이용되고 있는 국산골판지고지(KOCC)는 반복적인 재활용 으로 인하여 섬유장이 짧고 매우 각질화된 상태이며, 펄프 내 미세분 함량이 50%이상에 달 하고 있다. 또한 섬유의 표면이 인쇄잉크, stickies 및 각종 이물질로 오염됨에 따라, 섬유자 체가 보유하고 있는 섬유간 결합 능력이 저하된 상태이다. 국산 골판지 고지를 재활용한 골판지 원지의 생산 시 탈수성 및 강도 저하의 단점을 극 복하는 것은 생산성과 품질향상의 측면이외에 고지 재생을 촉진시킨다는 의미를 지니고 있다. 상기한 KOCC의 단점을 극복하는 방안으로 섬유분과 미세분의 적절한 분급을 통하여 초지 시 탈수저향을 감소시키고 더불어 종이의 강도를 개선하는 방안이 본 연구센터에 의해 고안되었다. 아울러 고온압착건조 처리를 활용한 종이의 물성 개선법이 국내에 이미 적용된 상태로 건조시간의 단축 및 종이의 제반물성을 개선시켜주게 되었다. 하지만 이미 열화된 KOCC에 고온압착건조 처리를 적용하여 밀도를 증가시킨다 할지라 도 천연의 UKP를 이용한 종이에 준 하는 강도를 얻는 데에 한계가 있었다. K KOCC 펄프의 섬유간 결합 능력을 개선시키기 위하여 본 연구에서는 Kneading처리와 지력증강제를 첨가를 함께 실시하는 방안을 검토하였으며, 고온압착건조된 골판지 원지의 표면에 코팅처리를 실시하여 그 효과를 분석하였다. 이를 통해 국산 골판지고지를 재활용한 골판지원지의 강도 극대화 방안을 탐색하고자 하였다.

• Journal of agriculture & life science
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• v.45 no.1
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• pp.89-99
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• 2011

This study was carried out to investigate effect of irradiation doses on quality of vacuum-packed dry-cured ham during storage. Dry-cured pork slices were vacuum-packaged in nylon/ polyethylene bags. Vacuum-packed dry curd pork was stored at $10{^{\circ}C}$ for 12 weeks after irradiation (0 kGy, 2.5 kGy, 5 kGy, 7.5 kGy and 10 kGy) and physicochemical properties of dry curd porks, such as meat color surface, thiobarbituric aicd reactive substances, volatile basic nitrogen, pH, microbial (total plate count, Lactobacillus) and sensory properties (color, flavor, overall acceptability) were investigated. Irradiation treatment decreased a*-value, TPC and Lactobacillus. Irradiation dose significantly (p<0.05) increased irradiation flavor and TBA value. However, irradiation dose decreased redness and sensory color in dry-cured ham. The quality of dry-cured ham was affected by the irradiation dose. The results suggested that dry-cured ham irradiated at 5 kGy dose may show optimum quality characteristics of the products as well as microbial safety.

• Proceedings of the Korean Society of Crop Science Conference
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• 2020.06a
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• pp.49-49
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• 2020

• Korean Journal of Food Science and Technology
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• v.51 no.5
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• pp.447-451
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• 2019

6-gingerol can be converted to 6-shogaol, one of the predominant active compounds found in ginger, via processing such as drying and extraction. Subcritical water extraction is the environmentally friendly method of extraction of bioactive compounds using only purified water as a solvent. This study investigated subcritical water extraction ($190^{\circ}C$, 15 min) of 6-gingerol, and 6-shogaol from dried ginger (Zingiber officinale) including drying conditions such as temperature (room temperature, 60, $80^{\circ}C$, and freeze drying) and time duration for drying (1-4 h). The amount of 6-gingerol was found to be reduced, and that of 6-shogaol was found to be increased depending upon the water content of dried ginger. Upon oven-drying ginger at $60^{\circ}C$ for 2 h, the maximum yields of 6-gingerol ($0.18{\pm}0.02mg/g$ fresh weight), and 6-shogaol ($0.47{\pm}0.02mg/g$ fresh weight) were obtained upon subcritical water extraction.

• Journal of the Korean Applied Science and Technology
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• v.36 no.4
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• pp.1219-1223
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• 2019

The skin condition varies by the parts of the face. This study intended to visualize the facial skin based on the characteristics including moisture, sebum, dryness, amount of dead skin cells, and roughness by sectionalizing the facial skin into 9 areas. A total of 98 female in their 20~35s were selected, and the characteristics of skin by area were selected and listed in the order, and the area they felt each characteristic most strongly was analyzed with a weight and the result was visualized. The result showed that the area where they felt dryness the most was around the lips and eyes, and the area where the largest amount of dead skin cells and rough skin existed was the chin. There was a significant increase in moisture content (p <.05), and 90.5% of satisfaction with dryness was satisfied. The result of this study will be used as a basic data for the development of a cosmetic mask pack or a functional cosmetic product for each part.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.11
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• pp.4455-4459
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• 2010

To evaluate the effect of jojoba oil massage in dry skin, 10 person with dry skin were selected and divided into two groups. One arm was treated with jojoba oil massage, the other arm wasn't treated. Jojoba oil Massage group were treated arm massage using jojoba oil for 10 minutes, 2 times per week for 4 weeks. The result was that jojoba oil massage group was increased in lipid and hydration. Especially, the more the number of massage times were increased, the more lipid and hydration were increased(lipid: t=-7.470, p<0.001(inner arm)/t=-4.666, p<0.01(outer arm), hydration:t=-3.966, p<0.01(inner arm)/t=-6.847, p<0.001(outer arm). Therefore, jojoa oil massage method was effective against dry skin.