• Fire Science and Engineering
• /
• v.27 no.4
• /
• pp.21-26
• /
• 2013

This study was performed to test the combustive properties of Pinus rigida plates treated with bis-(dimethylaminomethyl) phosphinic acid (DMDAP), bis-(diethylaminomethyl) phosphinic acid (DEDAP), and bis-(dibuthylaminomethyl) phosphinic acid (DBDAP). Pinus rigida specimens were painted in three times with 15 wt% bis-(dialkylaminoalkyl) phosphinic acid solutions at the room temperature. After drying specimen treated with chemicals, combustive properties were examined by the cone calorimeter (ISO 5660-1). It is supposed that the combustion-retardation properties were improved by the partial due to the treated bis-(dialkylaminoalkyl) phosphinic acids in the virgin Pinus rigida. Especially, the specimens treated with chemicals showed both the lower total smoke release rate (TSRR) ($16.94{\sim}18.92m^2/m^2$) and lower $CO_{2mean}$ production (1.98~2.09 kg/kg) than those of virgin plate. However the specimens treated with chemicals showed both the higher peak mass loss rate (PMLR) (0.1250~0.1297 g/s) and higher 1st-smoke production rate (SPR) (0.0153~0.0167 g/s) than those of virgin plate. Compared with virgin Pinus rigida plate, the specimens treated with the bis-dialkylamimoalkyl phosphinic acids showed partially low combustive properties.

• Korean Journal of Food Science and Technology
• /
• v.37 no.4
• /
• pp.678-684
• /
• 2005

Extraction conditions, spectrometric, and sensory properties of pigment extracts from green discolored garlic (GDG) were studied for development of green index to evaluate degree of green discoloration of garlic. GDG pigments were extracted using polar solvents, such as methanol, ethanol, and water. Methanol with 1% HCl resulted in highest extraction of green pigments. Extraction of pigments was affected by temperature, and extracted pigments were partially destroyed at high temperatures. Optimum conditions for extraction of green pigments were $20^{\circ}C$ for 30 min. Because green pigments are unstable at room temperature, and no method has been reported to evaluate degree of green discoloration of garlic, color chart was designed by mixing varying amounts of control and GDG. High correlation was observed between sensory scores and "a" value of color chart samples (y=-3.465x - 11.676) with $R^2$ of 0.993. Green index (GI) was developed based on linear regression equation between sensory scores and "a" values. Sensory panel recognized green discoloration of garlic at $GI{\geq}3.0$. GI developed in this study could be utilized to evaluate degree of green discoloration of garlic during cold storage and distribution of garlic.

• Korean Journal of Food Science and Technology
• /
• v.11 no.2
• /
• pp.86-92
• /
• 1979

Antioxidants. BHA, BHT and PG were added to a commercial soybean oil at a level of 200 ppm, and the antioxidant-treated oils and a control oil were subjected to 30 min. heating at $150{\pm}2^{\circ}C$ and 23.5 hr. cooling at room temperature for 6 times. Variations of % antioxidant retention and some physical and chemical properties of the oils were investigated. The results of the present study were as follows. 1. The % retention of BHA, BHT and PG after the second heating and cooling was respectively 60.5, 55.7 and 40.5 %. That of BHA, BHT and PG after the 6th heating and cooling was respectively 5.7, 3.0 and 1.8 %. 2. The refractive indices and viscosity of the oils, including the control, increased slowly at first. but after 4th heating and cooling, these values increased rapidly. The color indices of the oils, including the control, increased very rapidly, but after the 2nd heating and cooling, the rates of the increase diminished considerably. 3. The efficiency of each antioxidant in suppressing peroxide, thiobarbituric acid, and acid value development decreased rapidly as the antioxidant contents of the oils decreased. After the 6th heating and cooling, the peroxide. thiobarbituric acid and acid values of the oils treated initially with the antioxidants did not differ appreciably from those of the control.

• Journal of Life Science
• /
• v.13 no.2
• /
• pp.206-213
• /
• 2003

This study was conducted to estimate volatile compounds in pericarp of Zanthoxylum piperitum DC (Chopi). Chopi which harvested on lune 2, July 14 and September 11 in 2001 was dried at room temperature for one week. Fifty-two, 47, and 44 volatile compounds were analyzed with GC-MS in pericarp harvested on lune 2, July 14 and September 11, respectively. Eight terpenes including myrcene, ${\gamma}$-terpinene, $\alpha$-terpinolene, $\alpha$-phellandrene and $\beta$-caryophyllene were detected in pericarp harvested on tulle 2 and July 14, but not $\alpha$-phellandrene and $\beta$-caryophyllene in pericarp harvested on September 11. Thirteen alcohols or terpene alcohols including linalool L and citronellol were detected in pericarp harvested on lune 2, and added cis-linallol oxide and piperitol isomer in pericarp harvested on July 14 and September 11. Three aldehydes or terpene aldehydes were not affected by degree of maturation, but citronellal was increased in pericarp harvested on September 11. Five volatile compounds of ketones containing cryptone and piperitone were detected, and their concentration was changed during maturation. Six esters including lavandulyl acetate and $\alpha$-terpinenyl acetate were detected in pericarp harvested on lune 2, and [(E)-6,7-ephoxy-3,7-dimethyl-2-octenyl]ester of acetic acid was added in pericarp harvested on July 14 and September 11. Seven hydrocarbons including $\delta$-cadinene and neopentylidene cyclohexane were detected in pericarp harvested on June 2 and $\alpha$-muurolene was newly added in pericarp harvested on July 14 and September 11. We suggest that kinds and concentration of volatile compounds in pericarp were remarkably different from those in mature stage.

• Journal of Life Science
• /
• v.26 no.8
• /
• pp.943-947
• /
• 2016

The objective of this study was to see if fairly simple magnetic nano-particle treatment enhances boar semen qualities. Boar semen samples were prepared from the swine AI center and samples were divided by 4 different motility groups (1, >90%; 2. 80~90%; 3. 70~80%; 4. <70%) using computer assisted sperm analysis (CASA) evaluation. Boar semen was extended using BTS extender and same number of magnetic nano-particles as total number of spermatozoa in each sample was treated for 20 min and collected for 5 min at room temperature. Sperm qualities such as motility and viability were evaluated by the CASA before and after treatment. Sperm abnormality and degree of agglutination were also evaluated under the microscopic examination before and after treatment. There were significant changes (p<0.05) on sperm motility from all 4 different groups in the average of 7.11% after treatment. The enhancement of sperm motility changes was more clear in the groups of lower sperm motile groups (<70% and 70~80%; 19.12±1.08% and 5.67±0.71%, p<0.05). The sperm motility character in terms of curvilinear velocity (VCL), straight line velocity (VSL), average path velocity (VAP) and linearity (LIN, %) showed also similar pattern but motility enhancement wear more clear in below 70% motile group. Average sperm viability was increased to 4% by magnetic nano-particles (p<0.05). The percentage of sperm abnormality was also reduced significantly (p<0.05) to the range of 3.7~4.5% before after treatment. The degree of sperm agglutination was also reduced in lower motility groups by the magnetic nano-particle purification.

• Journal of Life Science
• /
• v.21 no.1
• /
• pp.56-61
• /
• 2011

This study was performed to investigate effective extract conditions in fronds of the Ostrich fern (Matteuccia struthiopteris) to increase antioxidant compound contents and antioxidant capacity. Powder (1 g) of lyophilizated fronds were mixed with 3 kinds of solvents (MeOH, 80% EtOH and water). Extractions were carried out using not only immersion (room temp.), heating ($60^{\circ}C$) and stirring (200rpm) for 6 hr, but also through sonication in a 42 kHz ultrasonic bath for 15, 30 and 45 min. Extracts were filtrated and measured for contents of soluble solids (SS), total polyphenols (TP; tannic acid as a standard) and total flavonoids (TF; Naringin as a standard). Antioxidant activity was expressed as $RC_{50}$ for DPPH and ABTS radical scavenging. SS (0.317 $g{\cdot}g^{-1}$ db), TP (70.90 $mg{\cdot}g^{-1}$ db) and TF (41.53 $mg{\cdot}g^{-1}$ db) contents reached their highest levels when 30 minute sonication extraction with 80% EtOH was performed, and the highest DPPH and ABTS scavenging activity was observed in the same extraction conditions ($RC_{50}$=0.14 $mg{\cdot}ml^{-1}$ and 0.09 $mg{\cdot}ml^{-1}$, respectively). From the present investigation, it can be concluded that fronds of the ostrich fern can be used as a natural material for antioxidants, and sonication for 15-30 min with 80% EtOH is an ideal extraction method for increasing their antioxidant effects and saving extraction time.

• Journal of Korean Home Economics Education Association
• /
• v.21 no.4
• /
• pp.19-33
• /
• 2009

The purpose of this study was to investigate fast food consumption, awareness of fast food and food habit of middle school students in Wonju area according to their intake frequency of fast foods. Subjects were categorized into 3 groups according to intake frequency of fast foods : frequent users($\geq$ 1 times/week, 29.5%) users(2~3 times/month, 50.7%), non-users($\leq$ 1 time/month, 19.8%). As for the purpose of eating fast food, many ate fast food between meals. The most favorite fast food was chicken regardless of intake frequency, followed by pizza, hamburger, the reason being that it tasted good. Regarding if there was any room for improvement, the largest number of the students asked for inexpensive price, irrespective of fast food intake frequency. Compared to users, non-users intake more diverse foods, vegetables, dairy products, fruits, protein foods and seaweed. Users or frequent users of fast food more felt drowsy, cold in the hand and foot, rough skin symptoms than non-users. In conclusion, frequent consumption of fast foods can lead unbalanced diet intakes for middle school students, and those who consumed fast foods frequently showed undesirable food habits in their daily meal.

• Journal of Korean Biological Nursing Science
• /
• v.3 no.1
• /
• pp.41-52
• /
• 2001

This study was undertaken to investigate the effects of n-6(corn oil) & n-3(fish oil) fatty acids on infarction size and the cerebral activities of antioxidant enzyme in rat focal brain ischemia model. Weaning Sprague-Dawley rats were fed with either corn oil supplemented diet(COD, 14% corn oil) or fish oil supplemented diet(FOD, 14% menhaden oil) for 6 weeks. The right middle cerebral artery was occluded for 2 hours with a silicon rubber coated nylon surgical thread. After 24 hours of recirculation, the rats were sacrificed and brain sections were photographed using CCD camera after staining with 2, 3, 5-triphenyltetrazolium chloride for 60 minutes in room temperature. The infarcted area was measured and the volume of infarction was calculated. Catalase(CAT), superoxide dismutase(SOD) activities, and fatty acid composition in the brain were also measured. The total and corrected infarction volumes were not significantly different between FOD and COD group. The docosagexaenoic acid(DHA) and DHA content/arachidonic acid(AA) ratio of the cerebral cortex, an index of defense against lipid oxidation, were significantly increased in FOD group compared to those of COD group(p<0.05). In the left cortex(non-infarction side) as well as the right cortex(infarction side) of FOD group, CAT and Cu/Zn SOD activities were higher than those of the COD group(p<0.05). However, CAT and Cu/Zn SOD activities were not significantly different between the left cortex(non-infarction side) and the right cortex(infarction side) of both FOD and COD group. GPx activities were also not significantly different between two groups. Our results demonstrate that the brain infarction size in FOD and COD were not significantly different. However, cerebral lipid composition and antioxidant enzyme activities in FOD and COD group were different. Fish oil, a source of n-3 polyunsaturated fatty acid(PUFA) and corn oil, that of n-6(PUFA) may have a protective effect against oxidative stress induced via different mechanisms.

• Korean Journal of Construction Engineering and Management
• /
• v.19 no.4
• /
• pp.102-110
• /
• 2018

The study analyzed the effects of the floor plan characteristics on the apartment price under the national housing size in 3 Gangnam districts for decades, the primary apartment markets in Korea. The analysis showed that the storage spaces such as kitchen, warehouses and dressage rooms have a positive effect on the price. Especially, the highly opened space with three-side open plan and the one with the unified type of livingroom, diningroom and kitchen have shown the strong effect on the price. For the kitchen spaces, the I-shaped kitchen tends to be more expensive while a centered living room has a positive effect on the price. These findings have an academic significance as the direct effects of plan characteristics on price has been examined unlike prior research focused on the analysis of trend, basic statistics, and satisfaction level. It is noteworthy that these research finding has identified the productive implication for the future floor plan design and pricing and also be implemented in the purchasing decision making by buyers in the housing market.

• Korean Chemical Engineering Research
• /
• v.51 no.3
• /
• pp.388-393
• /
• 2013

The study was focused to evaluate the possibility for combination membrane of bacterial cellulose (BC) and graphene with high electrical properties. BC with natural polymer matrix was known to have strong physical strength. For the combination of graphene with BC, the surface of graphene was modified with oxygen plasma by changing strength and time of radio waves in room temperature. Water contact angle of modified graphene grew smaller from $130^{\circ}$ to $12^{\circ}$. XPS analysis showed that oxygen content after treatment increased from 2.99 to 10.98%. Damage degree of graphene was examined from $I_D/I_G$ ratio of Raman analysis. $I_D/I_G$ ratio of non-treated graphene (NTG) was 0.11, and 0.36 to 0.43 in plasma treated graphene (PTG), increasing structural defects of PTG. XRD analysis of PTG membrane with BC was $2{\theta}$ same to BC only, indicating chemically combined membrane. In FT-IR analysis, 1,000 to 1,300 $cm^{-1}$ (C=O) peak indicating oxygen radicals in PTG membrane had formed was larger than NTG membrane. The results suggest that BC as an alternation of plastic material for graphene combination has a possibility in some degree on the part like transparent conductive films.