• Journal of Preventive Medicine and Public Health
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• v.19 no.1 s.19
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• pp.123-129
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• 1986

Fetal weight data from 84 litters of Sprague-Dawley rats were statistically analyzed for the effect of position in the uterine horn on fetal weight. The standard score obtained from the mean weight and standard deviation of all fetuses in a uterine horn were studied for position effect. In control group, the heaviest fetus occupied the middle position with a progressive decrease in weights toward the ovarian and cervical ends of the horn. But the effect related to position for the fetal weight was not statistically significant. In contrast, rats acutely or chronically exposed to carbon monoxide showed statistically significant positional differences of fetal weight within the uterine horns. The findings that the intrauterine position effect on fetal weight which is not signicant in control group may act one of confounders at the situation of transplacental toxicological studios.

• Journal of the Korean Society of Tobacco Science
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• v.23 no.2
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• pp.149-155
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• 2001

This study was carried out to evaluate the correlations among degree of carbonization, chemical components and chromatic characteristics, and to establish the criterion of carbonizaion in leaf tobacco during aging storage. The flue-cured (B2O) and burley (B2T) leaf tobaccos were redried with conventional practices for each other type, and moisture contents of leaf tobaccos were adjusted to 13, 15, 17 and 19% after redrying. The leaf tobaccos were packed in carton box and stored for 8 months in the controlled-environment rooms($35^{\circ}C$, 65% R.H. and $40^{\circ}C$, 80% R.H.). Degree of carbonization, chemical components, and chromatic characteristics(L ; black-white, a ; red to green, b ; yellow to blue) were invetigated every month. Carbonization Index (C.I.) was established as (equation omitted) in accordance with degree of carbonization in two types. The C.I. value of flue-cured leaf(56.5) for slight carbonization was higher than that of burley leaf(48.0). C.I. and rate of usable leaf, L and b were positively correlated in two types. C.I. was significantly shown positive correlation with pH in two types. The correlations between the predicted and the observed values of slight carbonizating times(month after storage) using C.I. and pH were positive significant in two types. The results suggest that cabonization index may be useful to forecast and prevent the carbonization, and pH may be useful to estimate cabonization indirectly for flue-cured and burley leaves during aging storage.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.6
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• pp.123-129
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• 2015

There are two kinds of cartons for beverage packaging, one is aseptic brick (AB) type and the other is gable top (GT). In this study, AB and GT were used as a raw material of recycled paper to investigate the recyclability at their varied blending ratios. Fiber consistency at pulping decreased as the blending ratio of AB increased. As a result, a lot of fines were generated from AB and flakes from GT increased because shear force in pulper decreased. Bulk of handsheets was more than $2.0cm^3/g$, and ISO brightness decreased as the blending ratio of AB increased. The best condition to recycle beverage cartons is to discriminate each cartons separately because of differences in the composition. However, there are problems such as the limit of the collection system and social costs. Therefore, it is assumed that the blending ratios of AB should be adjusted at less than 20% for effective recycling of beverage cartons.

• Korean journal of applied entomology
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• v.8
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• pp.19-23
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• 1969

It was observed that the effect of Grand E.C, on the growth of Fusarium oxysporium f. cucumerinum mycellia, which was cultured in the media with different nitrogen and carton sources, varied with it's concentrations. (1) Mycellia of F. oxysporium f. cucumerinum were grown strongly in $(NH_4)_2HPO_4\;NH_4NO_3$ and fructose media. (2) In general, the diluted Grand E.C, $ (\times\;1,000)$ effected on check of fungal growth in any type of media with the different nitrogen and carbon sources. It was disturbed the growth of fungi in $NH_4NO_3$, lactose and fructose in the diluted fungicide $(\times\;5,000)$. In the diluted solution $(\times\;10,000)$ of fungicide, somewhat increased the viability of fungi, but it was disturbed the growth in $NH_4NO_3$ and fructose media. (3) In conclusion, it was thought to be that the diluted Grand emulsion effected in check of the growth of F. oxysporium f. cucumerinum which grown some nutritional conditions.

• Korean Journal of Agricultural Science
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• v.47 no.3
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• pp.415-424
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• 2020

This study investigated the effects of an ethylene scrubber (ES) with a micro-perforated polypropylene (MP-PP, 30 ㎛) or a high density polyethylene (MP-HDPE, 30 ㎛) film liner for the export carton packaging box in 'Campbell Early' grapes. Rachis browning was highest in the untreated group, followed by MP-PP and MP-HDPE for 14 days of simulated marketing at 20℃. The combination treatment of ES with the film liners showed a partial inhibition of the rachis browning regardless of the film liners. The effects of an alcohol releaser (AR) sachet or chlorine dioxide (CD) diffuser co-packaging were also investigated in the 'Campbell Early' grapes packed with the MP-HDPE (40 × 99 pin hole·m^-2) film liner. The CD 1 g treatment showed a very limited weight loss of 1.1%, which was significantly lower than the 4.7% of the untreated control after 14 days of simulation marketing at 20℃. The berry shatter was 0.7% for the MP-HDPE + CD 1 g treatment and 1.8% for the MP-HDPE + CD 5 g treatment on the 10th day of the simulated marketing, which was significantly lower than the 8.9% of the control. The stem browning was significant suppressed until the 10th day of the simulated marketing. In particular, the CD 1 g treatment in combination with the MP-HDPE showed a low rachis and pedicel browning index of 2.0, which is 50% and 40% lower than that of the untreated control and the MP-HDPE single treatment, respectively. In addition, the CD 1 g treatment group showed a higher decay reduction effect than the CD 5 g treatment group, which caused high concentration damage.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.4
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• pp.381-387
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• 2007

The excellent dielectric properties of $SF_6$(sulfur hexafluoride) have lead to its wide range of application in the field of high voltage insulation. Because there has been some recent concern regarding the environmental impacts of $SF_6$ binary gas mixtures, with $SF_6$ as the main component, have been the subject of active research. Scientists have long been interested in the possible use of gaseous fluorocarbons, including $CF_4$ (Carton Tetrafluoride), in high voltage applications due to their inert character and high dielectric strength. This paper presents experimental results concerning the AC breakdown characteristics lot various mixtures of $SF_6/CF_4$ in a test chamber and 25.8 kV GIS (Gas Insulation Switchgear) at practical pressures (0.1-04 MPa) and gap lengths (0.5 mm, 1 mm) in a test chamber. In the result, it was observed that an increase in the dielectric strength is attained through the addition of $SF_6$ to $CF_4$. It is possible to make an environment friendly gas insulation material while maintaining the dielectric strength by combing $SF_6$ and $CF_4$ which generates a lower level of the "global warming" effect.

• Polymer(Korea)
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• v.29 no.5
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• pp.481-485
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• 2005

In this work, the thermal and mechanical properties of vapor grown carbon nanofibers (VGCNFs)-reinforced difunctional epoxy (EP) composites were investigated in the presence of the 0, 0.1, 0.5, 1.0, and $2wt\%$ VGCNFs. The thermal properties of the VGCNFs/EP composites were studied by thermo-mechanical analysis (TMA) and dynamic mechanical analysis (DMA). The mechanical properties of the VGCNFs/EP composites were also examined by universal testing machine (UTM), falling impact test, and the friction and wear tests. From experimental results, the thermal and mechanical properties of the VGCNFs/EP composites were improved with increasing the VGCNFs contents. This was due to the increase of crosslinking structure of the composites, resulting in improving the mechanical interlockings between VGCNFs and epoxy resins in the present composite system.

• Korean Journal of Poultry Science
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• v.7 no.1
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• pp.1-11
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• 1980

About 6 to 8% of the eggs annually produced are broken or cracked between the hen and the consumer's carton. The majority of this breakage is due to interrelationships between egg shell quality and the many biological, environmental and managerial factors which have been individually identified as affecting breakage. Some of the factors associated with shell damage discussed in this review include age of hens, temperature ana humidity of the laying house, design of the cage systems and of the cage floors, type of material used to manufacture the cages frequency of daily egg collection in the laying house and, Probably most important, the frequency and quality of handling equipment maintenance. Age and genetic constitution of the hens, environmental temperature, and design and quality of equipment maintenance are the major factors that influence shell breakage. There is a curvilinear relationship between shell quality and shell breakage which explains why small changes in shell quality may be associated with large changes in the incidence of breakage. Published data indicate the incidence of breakage may range from as low as 1 to 2% to 35% or more for other egg producers.

• Food Science and Preservation
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• v.6 no.4
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• pp.371-375
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• 1999

This study was conducted to investigate the effect of precooling on the qualify of Tsugaru apple. Tsugaru apple, filled in plastic container and carton, was precooled by pressure cooler and stored at 1$^{\circ}C$and 25$^{\circ}C$. At 25$^{\circ}C$, Hunter a-value was not shown the difference significantly and Hunter b-value was increased more than a-value during l month. However, Hunter a and b-value was not increased so much at 1$^{\circ}C$. Hardness and toatal acidity was decreased during storage and precooled apple was less decreased than non precooled. Free sugars in Tsugaru apple was consisted of 7.07% fructose, 2.85% glucose, and 2.53% sucrose. Free sugars were decreased during storage at 25$^{\circ}C$ and 1$^{\circ}C$, also, the precooling inhibited those decomposition.

• Food Science and Preservation
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• v.6 no.4
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• pp.365-370
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• 1999

This study was conducted to investigate the effect of precooling in the prolongation of freshness of Tsugaru apple. Tsugaru apple was precooled to 1$^{\circ}C$ by the pressure cooler and stored at 1$^{\circ}C$ and 25$^{\circ}C$. Precooling time was required about 5 to 6 hours for Tsugaru apple that filled in the plastic container and faster than that in the carton. The respiration rate was decreased with the reduction of the product temperature by precooling. Tsugaru apple could store about 9 days and 35 days at room temperature and 1$^{\circ}C$, respectively.