• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.22 no.3
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• pp.127-134
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• 2016

In this study, Biodegradable masterbatch (M/B) was prepared by different kinds and content of biodegradable catalysts added to oxo biodegradable plastics. The bio film was prepared by adding biodegradable M/B to the polyethylene pellet, and the change of physical properties by UV and heat treatment and the stability as food packaging material were confirmed. As a result of the physical property change, Fe salt and Al salt bio film was superior to Ni salt bio film about a decrease in physical property. However, considering the raw material cost and industrial availability, M/B containing Fe salt was selected and additional experiments were conducted by concentration. The bio films prepared with Fe salt M/B 1.0, 1.5 and 2.0 wt% showed excellent physical properties.

• Korean Journal of Plant Resources
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• v.10 no.2
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• pp.169-174
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• 1997

This study was conducted to obtain basic information needed to develop the effective weed control method by using thermal weeder which uses LPG as fuel. For survey of weed distribution in herb field, weed species were investigated at two kinds of herb field of Codonopsis lanveolata and Aster scaber located in Hoengseongkun and Hwacheonkun, Kangwondo. In Codonopsis lanveolata field, Digitaria sanguinalis and Persicaria viridis L were dominated. In Aster scaber field, Digitaria sanguinalis and Erigeron canadensis were dominated. In general, Grasses weeds in herb were more dominated than other broadleaf and Cyperaceae weeds. The treatments of $H_2SO_4$ in weed seeds were more effective for germination of several weeds, compared with that nontreated weed seeds. However, the rate of germination differed depending on weed species and tereatment time of $H_2SO_4. Also, viability of weed seeds was significantly affected by irradiation time and temperature. As the temterature and treatment time of irradiation increased, the rate of germination was decreased.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.6
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• pp.901-908
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• 2014

Blueberries and strawberries are highly perishable and easily contaminated with microorganisms. To maintain the quality of these commodities during refrigerated storage, the effects of two packaging materials as well as passive modified atmosphere packaging on the quality of blueberries and strawberries were investigated. The harvested blueberries and strawberries were first treated with combined non-thermal treatment of aqueous chlorine dioxide and fumaric acid, followed by packaging with polyolefin film (6,000 mL $O_2/m^2{\cdot}24hr{\cdot}atm$ at $24^{\circ}C$) and polyamide/polyamide/polyethylene film (PA/PA/PE, 60 mL $O_2/m^2{\cdot}24hr{\cdot}atm$ at $24^{\circ}C$), respectively. After combined sanitizer treatment, the populations of total aerobic bacteria in blueberries and strawberries were reduced by 2.50 and 1.97 log CFU/g while those of yeast and molds were reduced by 1.95 and 2.18 log CFU/g, respectively, compared with the control. In particular, microbial growth in these samples packed with PA/PA/PE film was reduced during refrigerated storage. In addition, the blueberries and strawberries packed with PA/PA/PE film underwent lower weight loss than those packed with polyolefin film during storage. These results suggest that appropriate packaging with proper gas permeability is necessary to maintain the quality of blueberries and strawberries during refrigerated storage.

• Food Science and Preservation
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• v.13 no.1
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• pp.8-12
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• 2006

The effects of packaging treatments with either low density polyethylene (LDPE) or polypropylene (PP) films on the quality of leaf lettuce were evaluated. It was also stored within a plastic bag (LDPE and PP films) with 4 pelf orated holes (6mm diameter). Changes in weight loss, color difference, anthocyanin, chlorophyll, water content, and general appearance (shape of lettuce) ware investigated Total weight of leaf lettuce packaged within non-pelf orated films decreased slowly over the storage periods at 5 and $20^{\circ}C$. The weight loss of leaf lettuce showed no significant difference between non-pelf orated and perforated films at $20^{\circ}C$. General appearance in leaf lettuce stored at $20^{\circ}C$ was not significantly affected by packaging treatments with LDPE and PP films. The shelf life of non-packaged leaf lettuce at $5^{\circ}C$ was 8 days, whereas packaging treatments with LDPE and PP films showed freshness in leaf lettuce for 30 days of storage. Total chlorophyll and water contents of leaf lettuce packaged within pelf orated and non-pelf orated films decreased gradually during storage. However, no remarkable changes in color difference, levels of chlorophyll and anthocyanin, and water contents were observed in leaf lettuce packaged within perforated and non-pelf orated films. In this experiment, leaf lettuce packaged within LDPE or PP films without any punching holes at $5^{\circ}C$ was the most desirable for extending the quality. These results suggest that non-pelf orated packaging treatment in combination with low storage temperature could be effective in prolonging the shelf life of leaf lettuce

• Korean Journal of Food Science and Technology
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• v.41 no.4
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• pp.374-379
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• 2009

In this study, we investigated effects of different packaging materials and methods on physico-characteristics of green pumpkin during storage at $10^{\circ}C$. Whole green pumpkin samples were packaged with polyvinyl chloride film (PVCF), orange coating film (OCF), paraffin film (PF), or paper with paraffin film (PWPF) and stored at $10^{\circ}C$. Weight loss, pH, firmness, browning, and gas composition ($O_2$ and $CO_2$) inside the film packages were evaluated. All characteristics of the unpackaged group (control group, CON) changed rapidly and lost marketability as compared with the packed pumpkin group. The pH values in all of the green pumpkin samples were between 6.38 and 6.67, and decreased with increased storage time. Over the storage time, all packaged pumpkin groups evidenced prevented or retarded deterioration of the green pumpkin samples in terms of appearance, texture, and discoloration. Firmness decreased slightly with increased storage time. Brown color difference were much higher in the controls than in the film-packaged green pumpkin samples, and increased rapidly in the early stages of storage. These results were attributed to reduce respiration rates as a result of elevated carbon dioxide and reduced oxygen levels in the packages. The results of this study demonstrated that the green pumpkin packaged with PWPF and PVCF showed retarded deterioration as compared to the CON, OCF and PF samples in a controlled atmosphere, and thus significant differences were noted according to the packaging material and methods used.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.21 no.2
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• pp.79-84
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• 2015

Pre-drying of 'Fuyu' persimmon was performed right after harvesting from a farm. Pre-drying conditions were varied with room temperature (RT) for 1 day to 7 days, low temperature (LT, at $20{\sim}30^{\circ}C$) for 1 day to 4 days, high temperature (HT, at $30{\sim}40^{\circ}C$) for 3 h to 12 h, and ultra-high temperature (UT, at $50{\sim}60^{\circ}C$) for 30 min to 120 min. Weight loss of pre-dried persimmon was increased from 1.62% up to 2.96% with increased pre-drying temperature and time. Pre-drying at RT resulted more significant weight loss of persimmon compared to that of pre-drying at HT. Minimum firmness loss of persimmon stored at $0^{\circ}C$ for 100 days was obtained at the condition of HT for 6 h. Rate of peel blackening was decreased from 31.5% to 16.4% and 10.9% by pre-drying at HT for 6 h and 9 h, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.4
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• pp.477-482
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• 1986

This trial was carried out to set up a proper drum speed of thresher to minimize the mechanical damage from threshing and thereby to obtain rye seeds possessing higher qualities for seeds. Rye plants were harvested at from 40 to 60 days after heading (DAH) with 5 days intervals and spread out on the field for 0, I, 2, 3 days for drying, respectively. After drying the plants were subjected to threshing at seven steps of drum speed from 400 to 1000 rotation per minute (RPM) of a thresher, drum diam. 18.6cm, teeth length 6cm. At 500 to 600 RPM and from the plants harvested at 55DAH with drying for one or two days, the seeds possessed low grain damage, high germinability over 90%, and field emergence rate over 80%.

• Journal of Korean Ophthalmic Optics Society
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• v.11 no.4
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• pp.323-327
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• 2006

For this study we research investigated the current situation of packing on the labeling items of domestic spectacle lens and reliability of spectacle lens. We use sample which is three hundred and ninety six spectacle lenses of eight company total. Refractive index of each sample in experiment is 1.55~1.56, 1.60~1.61 and 1.67. The percentage of labeling of A company and B company indicated the percentage of labeling of 80%, but The percentage of labeling of two companies indicated only 52.1% and 56.9% seperately. The most companies indicated comparatively a low marking ratio about packing on the labeling items. The results of difference the value of power which is recorded with the value of power which is measurement showed only small value.

• Journal of the Korean Geotechnical Society
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• v.32 no.5
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• pp.49-55
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• 2016

This study aims to present the practical Nitrogen monoxide (NO) removal capacity of cement mortar with Titanium dioxide ($TiO_2$) which is one of the paving materials by considering the environment of pavement in urban areas. NO removal capacity test under designated conditions of humidity of inflow gas and the test with variation of the degree of saturation of specimen were conducted. In the test for humidity, dry specimen is subject to the test and NO removal ratio was observed. Humidity-NO removal ratio curve is a log normal distribution in shape, and the maximum NO removal ratio appears at specific humidity. NO removal capacity test relying on the degree of saturation was carried out with wet specimen to reflect the unsaturated pavement by rainfall and domestic sewage. Wet specimen presents less NO removal capacity than dry specimen and the recovering evolution of NO removal capacity follows evaporation. Moreover, $TiO_2$ under the specific depth of specimen hardly contributes to NO removal capacity.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1999.04a
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• pp.79-82
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• 1999

실험기간 중 실내 평균기온과 상대습도는 외부보다 각각 $1.5^{\circ}C$ 및 3.9%정도 다소 높게 나타났다. 그리고 일사량 투과율은 약 47%정도로서 6.51MJ정도였다. 포장재배의 경우가 포트재배의 경우보다 주당 옆면적, 간장 및 수확량이 많았다. 그리고 포장의 총수확량은 3,901g/p1ant로서 포트재배 평균 2,853g/plant 보다 많게 나타났다. 총소비수량은 각각 약 1,394mm, 819mm정도로서 포트재배의 경우가 약 2배정도 많게 나타났다. 실내 평균기온, 최저상대습도 및 일사량과 소비수량과의 상관관계를 살펴보면, 평균기온과 일사량과는 깊은 상관이 있었으나, 그 이외에는 상관이 거의 없는 것으로 나타났다. 작물환경요소인 간장과 소비수량과는 밀접한 상관관계가 있었고, 엽면적 및 수확량과 소비수량과의 상관관계는 조금 떨어지는 것으로 나타났다. 요수량은 포장재배의 경우가 8.6mm/g이었고, 포트재배의 경우는 10.5mm/g정도이었다.