The unique features of spark plasma sintering process are the possibilities of a very fast heating rate and a short holding time to obtain fully dense materials. -SiC powder with 0, 2, 6, 10 wt% of -SiC particles (seeds) and 4 wt% of Al-B-C (sintering aids) were spark plasma sintered at for 10 min. The heating rate, applied pressure and sintering atmosphere were kept at , 40 MPa and a flowing Ar gas (500 CC/min). Microstructural development of SiC as function of seed content and temperature during spark plasma sintering was investigated quantitatively and statistically using image analysis. Quantitative image analyses on the sintered SiC ceramics were conducted on the grain size, aspect ratio and grain size distribution of SiC. The microstructure of SiC sintered up to consisted of equiaxed grains. In contrast, the growth of large elongated SiC grains in small matrix grains was shown in sintered bodies at and the plate-like grains interlocking microstructure had been developed by increasing sintering temperature. The introduction of -SiC seeds into -SiC accelerated the grain growth of elongated grains during sintering, resulting in the plate-like grains interlocking microstructure. In the -SiC seeds added in -SiC, the rate of grain growth decreased with -SiC seed content, however, bulk density and aspect ratio of grains in sintered body increased.
This study was designed to estimate the effect of ethanol addition on shelf-life extension and changes in growth of total aerobic bacteria in fresh wet noodles. The wet noodle was made with addition of 0, 1 and 2% ethanol. During the storage at 10oC, wet noodles were monitored changes in the total numbers of aerobic bacteria. A 6 log cfu/g was applied as a standard for microbiological quality of foods. As a result, the shelf-lifes of wet noodle with addition of ethanol at the standard were 9.17 days at no ethanol, 15.02 days at 1% ethanol and 27.03 days at 2% ethanol. The respective percentage increases in the shelf-life observed at both 1 and 2% ethanol addition were 63.8% and 194.8% comparing with no ethanol treatment. Consequently, addition of ethanol into fresh wet noodle inhibited growth of total aerobic bacteria and extended shelf-life.
This study was conducted to investigate the effects of herbs (dill weed, fennel seed and rosemary) on color stability and lipid oxidation of ground pork patties during storage at 2oC and −20oC. Lipid oxidation was determined by the thiobarbituric acid reactive substances (TBARS) method. Fennel seed was identified as being the most effective ingredient in terms of meat redness (Hunter a-values) during storage at 2oC (p<0.05). Patties treated with rosemary had lower Hunter a-values than control, and dill weed was the least beneficial in influencing meat redness, having significantly lower a-values than control patties. During frozen storage at −20oC, no significant differences in a-values were observed between the control patties and those treated with fennel seed. Patties treated with rosemary had lower a-values than control and patties with dill weed had negative a-values throughout storage. The cooking process increased Hunter L-values and decreased a-values in all patty samples. TBARS values increased during storage. Rosemary displayed excellent antioxidative activity as evidenced by the completely inhibition of TBARS formation of cooked pork patties. Dill weed and fennel seed also exerted an intermediate but significant antioxidant effect during storage (p<0.05).
BaTiO3/epoxy composites have been widely investigated as promising materials for embedded capacitors in printed circuit boards. It is generally known that the dielectric constant (K) of the BaTiO3/epoxy composites increases with improvement of the dispersion of BaTiO3 particles in the epoxy matrix that comes from adding surfactant. The influences of surfactant addition on the dielectric properties of the BaTiO3/epoxy composites are reported in the present study. The dielectric constant of the BaTiO3/epoxy composites is not significantly affected by the surfactant addition. However, the temperature coefficient of capacitance increases and the peel strength decreases as the amount of added surfactant increases. The influences of surfactant addition on the dielectric properties of the neat epoxy are also very similar to those of the BaTiO3/epoxy composites. The residual surfactant in the BaTiO3/epoxy composites affects the temperature coefficient of capacitance and the peel strength of the epoxy matrix, which in turn affects the temperature coefficient of capacitance and the peel strength of the BaTiO3/epoxy composites.
목적: 누진가입도렌즈 피팅용으로 개발된 이동식 코받침(Moving Nose Pad, MNP)의 임상성능을 평가하여 누진가입도렌즈의 피팅실무에 효과적인 지침을 제시하고자 하였다. 방법: 현재 누진가입도렌즈를 착용하며 본 연구의 취지에 동의한 55명(남자 48명과 여자 7명)(평균 나이 53.1±4.6세)을 선정하였다. 현재 착용 중인 안경의 피팅 상태와 사용 만족도를 평가하고, MNP로 교체했을 때 피팅상태의 변화를 측정한 다음 2주 동안 사용한 후 자각적 만족도를 평가하였다. 결과: MNP로 교체된 안경을 착용하고 원거리와 근거리를 주시할 때 피팅상태의 변화는 피팅기준점높이와 정점간거리에서 유의한 차이를 보였다. MNP로 교체된 안경을 2주 동안 착용한 후 자각적 만족도를 조사한 결과, 47%가 컴퓨터 작업을 할 때 흐려 보임을 경험했고 그 가운데 95%는 안경을 위쪽으로 이동시켰을 때 선명한 시력을 얻었다. 82%가 독서할 때 흐려 보임을 경험했고 그 가운데 96%는 안경을 위쪽으로 이동시켰을 때 선명한 시력을 얻었다. MNP로 교체된 안경에 적응하는 시기는 86%가 1주일 이내라고 응답하였다. 결론: MNP로 교체된 안경의 피팅상태가 유의한 변화를 보였지만, MNP로 인한 적응기간이 별도로 필요하지 않으며, 누진가입도렌즈에 적응하기 어려운 불편감을 경감시키거나 추가로 발생할 수 있는 비용을 절감하는 효과가 있을 것으로 생각된다.
느타리버섯의 배지에 철, 고춧가루, 은행잎을 첨가하였을 때 버섯의 생육과 생리활성을 분석한 결과는 다음과 같다. 수량은 춘추 품종에 철 34.9g을 첨가하였을 때 144g으로 가장 높았고, 나머지 품종간에는 차이가 없었으며, 34.9g 및 174.5g 처리시 17.4g 처리에 비해 수량이 높은 경향이었다. 자실체와 배지에 포함된 무기물의 함량은 종류별로 차이가 있었으며, 배지중 철의 함량이 증가하여도 자실체내의 철의 함량은 0.31∼0.43mg/kg으로 거의 일정하게 유지되었다. 배지에 포함된 고춧가루의 함량이 많아질수록 자실체에 포함된 캡사이신의 함량도 많아졌으며, 수한품종에서 6mg/100g으로 가장 많이 전이되었다. 철이나 고추를 첨가한 배지에서 재배한 버섯에서 페놀성 화합물의 함량이 높게 나타났으며, 항산화력과 총 페놀성 화합물 함량, 환원력과 총페놀성 화합물 함량, 금속이온 제거능과 페놀성 화합물의 함량 간에는 서로 영향을 미치지 않는 경향이었다. Macrophage 활성화능은 수한 품종이 다른 품종에 비해 높은 경향이었다.
This study investigated the influences of the addition of lactic acid bacteria inoculants and an enzyme during the crush processing of com silage on the nutritive value, nutrient intake and aerobic deterioration. The fermentation quality of the silages showed that although all of the silages were of good quality, the V-score of U was 91.0 points and significantly lower than those of other silages (P<0.01). On the chemical composition of silages, the crude protein concentration of U was 7.1%DM and significantly lower than those of other silages (P<0.05). On the digestibility, the nutritive value and nutrient intake did not significantly differ among the silages examined. After silo opening, a rapid rise in heat was seen from the 6th after opening for 11C38 and SLA, and from the 9th in U and SL, respectively.
Yackwa was prepared by substituting syrup with xylitol (0, 10, 20, and 30%) and the quality characteristics were evaluated. Volume and specific volume were higher in Yackwa prepared with xylitol than the control. Crude fat content ofxylitol-containing Yackwa were significantly higher than that of control (p<0.05), but moisture content was not different among treatments. Incorporation ofxylitol in Yackwa lowered the redness and yellowness values (p<0.05). Instrumental hardness results showed that the addition of xylitol decreased the hardness ofYackwa. Sensory evaluation revealed no significant difference in overall desirability between controland xylitol-containing groups. Therefore, Yackwa made with up to 30% xylitol in place of syrup is as acceptable as control Yackwa without depressing sensory quality.
소형의 담액 수경재배기를 이용하여 기본 배양액에 셀레늄(Se) 1mg L-1과 계면활성제 PVA-95(polyvinyl alcohol-95) 1, 2, 4mg L-1과 CLS(calcium lignosulfonate) 5, 25, 50, 100mg L-1을 처리하여 청경채와 상추 식물체의 Se과 양이온 함량, 생육, 그리고 비타민 C 함량을 조사하였다. 생육은 처리간에 차이는 있지만 종류와 농도 별로 일정한 경향을 보이지 않았다. 총 비타민 C 함량은 두 작물 모두 모든 처리구에서 대조구에 비해 약간 증가하는 경향을 보였으나 유의성은 없었다. K 함량은 싱추의 경우는 일정한 경향이 없었지만, 청경채의 경우 Se 1+PVA-95 4mg L-1 처리구가 가장 높았고, Se 1+CLS 처리에서는 대조구에 비해 5mg L-1 농도에서는 증가하였지만 처리 농도가 증가할수록 감소하였다. Ca 함량은 두 작물 모두 Se 1+PVA-95와 CLS 처리에서 대조구에 비해 증가하였다. Mg 함량은 상추에서는 계면 활성제 처리에 의한 Mg 함량의 변화가 없었으며, 청경채에는 Se 1+CLS 25mg L-1 처리구가 대조구에 비해 증가하였고 기타 처리는 차이가 없었다. 식물체내 Se 함량은 상추에서는 계면 활성제 PVA-95 처리와 CLS 처리가 대조구에 비해 Se 함량이 모두 높았고, PVA-95 처리에서는 농도의 증가에 따라 Se 함량이 낮아졌으며, CLS 처리에서는 50mg L-1 까지는 높아졌지만 100mg L-1에서는 낮아졌다. 청경채의 엽내 Se 함량은 계면활성제 PVA-95 처리가 큰 효과가 없었으나 CLS 25mg L-1 처리에서 현저히 증가되었다.
목적: 본 연구는 노안의 직업과 굴절상태에 따른 누진다초점 안경 착용 실태를 분석하고자 실시되었다. 방법: 2008년 1월부터 2008년 12월까지 부천과 서울지역의 안경원을 방문한 40~70대 노안 가운데 노인성 안질환과 전신질환이 없고 누진다초점 안경을 착용하는 332명을 대상으로 선정하여 원거리 굴절이상도를 확인한 후 굴절이상이 있는 경우 원용굴절이상을 완전교정하고 평소 주시거리에서 근용가입도를 측정하였다. 결과: 연령과 가입도의 크기가 유의한 차이가 있는 것으로 나타났으며(p=0.001), 직업과 가입도의 크기도 유의한 차이가 있는 것으로 조사되었다(p=0.001). 직업별 누진다초점 안경 착용률은 주부가 46.1%, 사무직이 24.1%, 공무원이 13.0%로 주부가 가장 많이 착용하는 것으로 조사되었고, 굴절상태에 따른 누진다초점 안경 착용률은 정시가 18.4%, 직난시가 7.8%, 도난시가 35.8%, 사난시가 17.8%, 단순굴절이상안이 20.2%로 난시안에서는 도난시가 누진다초점 안경을 가장 많이 착용하는 것으로 조사되었다. 결론: 누진다초점 안경을 착용하는 노안 가운데 주부와 사무직(공무원 포함)이 상당한 비율을 차지하고 있었고, 굴절상태에서는 정시와 도난시안의 착용률이 높았다.
In this study, the potential possibility of oxygenates on butyl ether(below BE) was investigated as an combustion activator for a direct injection diesel engine. It tested to estimate change of engine performance and exhaust emission characteristics for the diesel fuel and oxygenates additives blended fuel which has four kinds of blended ratio. The smoke of blended fuel(diesel fuel 80vol-%+BE 20vol-%) was reduced in comparison with diesel fuel, that is, it was reduced approximately 26%. And, power, torque and brake specific fuel consumption(BSFC) didn't have no large differences. But, NOx of BE blended fuel was increased compared with diesel fuel.
The compaction response of nano powders with an addition of Ti powders prepared by magnetic pulsed compaction and subsequent sintering processes was investigated. All kinds of different bulk exhibited an average shrinkage of about 12% for different MPCed pressure and sintering temperature, which were approximately 50% lower than those fabricated by general process (20%) and a maximum density of around 92.7% was obtained for 0.8GPa MPCed pressure and sintering temperature. The addition of Ti powder induced an increase in the formability and hardness of the sintered . But the lower densities were obtained on sintering with addition of over 10 (wt%) Ti powder due to generation of crack during sintering. Subsequently it was verified that the optimum compaction pressure in MPC and sintering temperature were 0.8GPa and , respectively
This study was performed to elucidate the effects of addition of and bovine serum albumin (BSA) in vitro maturation (IVM) and in vitro culture (IVC) medium on porcine embryo production. The development rate to the 2 cell () and blastocyst stages () with different BSA concentrations in IVM medium were similar among treatment groups. Blastocyst hatching rate was significantly higher in the control group (0.0mg/ml) than in the group of 1.0mg/ml supplement (20.0% vs. 0.0%; p<0.05). The development rate to the 2 cell () and blastocyst stages () with different concentrations in IVM medium was similar among treatment groups. The development rate to the blastocyst was significantly higher in the group of 1.0mg/ml(15.3%) than in the group of 0.5mg/ml supplement (7.6%, p<0.05). The development rate to the 2 cell and blastocyst stages following the first addition of in IVM medium was significantly higher in the control group (77.0% and 18.9%) and was (77.2% and 16.9%) greater than that observed in other treatment groups (p<0.05). The development rate to the 2 cell stage () and blastocyst stages () with different BSA concentrations in IVC medium was similar among treatment groups. However, blastocyst hatching rate was significantly higher in the group of 3.0mg/ml supplement (30.0%) than in the control group (0.0%; p<0.05). The development rate to the 2 cell stage (), blastocyst () and hatching stages () were not different. The development rate to the 2 cell stage (), blastocyst () and hatching stages () at the different culture periods were similar among treatment groups. This study suggested that if the addition level and periods of addition are adjusted, it is possible to replace BSA in the in vitro porcine embryo production.
For the fabrication of core-shell structure bimetallic lead-free solder balls, both the critical temperature (Tcr) for the phase separation of two immiscible liquid phases and the temperature coefficient of the interfacial tension between the two separated liquid phases are required. In order to obtain this information, the temperature dependence of the surface tension of 60%Bi-24%Cu-16%Sn(-REM) alloys was measured using the constrained drop method. The slope of the temperature dependence of the surface tension changed clearly at a critical temperature for the separation of two immiscible liquid phases. The critical temperature of the 60%Bi-24%Cu-16%Sn alloy was estimated to be 1097K. An addition of 0.05% Ce decreased the critical temperature to 1085K, whereas that of 0.05% La increased it to 1117K. It was found that the surface tension and its temperature coefficient of the 60%Bi-24%Cu-16%Sn alloy were slightly increased by the addition of 0.05% Ce and 0.05% La. In addition, additions of Ce and La increased the temperature coefficient of the interfacial tension.
Purpose : To provide eye care practitioners with guidelines in selection of lenses based on visual needs of wearer. we measured optical characteristics and analysing distance, intem1ediate. and near zones of each PAL design. Methods : 34 lenses which are selling in the market currently, were ordered through a shop as if for a patient with a prescription of piano distance and a + 2.000 add for right respectively. The total number of tl1e lenses was 34 and they were obtained from the manufacturer directly to get a equatable of lenses. Each lens optics was measured with VM 2000(Visionix Ltd. Israel) three times. Limiting the viewing zone width by 0.500C or + 0.250S. distance. intem1ediate. near viewing zone were analysed respectively by lmm vertical steps. Results : Setting the criterion at addition + 2.000. the maximum unwantcd astigmatism was - 1.95 to -3.560( -2.32±0.37). clistance viewing zone area was 9.17 Lo 91.25 mm2(30.57±17.20 mm2 ) . intermediate vie\ving zone area was 10.52 to 41.21 mm2(19.56±6.88 mm2 ), the highest occurrence of the + 1.750 was apart 10.35 m to 18.16 mm(l3.53±2.02 mm) from fitting cross. and neru· viewing zone area with over + 1.750 was 26.58 to 111.25 mm2(62.31± 18.07 mm2 ). There were significant differences with measurement variables. And the usage ratings were measured on t11e criterion of the distance zone. intermediate zone. and near zone width and their horizontal width. Conclusions : The optical characteristics across the progressive addition lenses tested in this study were showed a variance of wide ranges. The ratings of visual needs of wearer on the distance zone, intermediate corridor and near zone can be used in selection of appropriate lenses to match individual specific needs.
The effect of Al(OH)3 on physical, thermal, and retardant property of rubber was studied. It was analyzed by statistical experimental design method with one way array to confirm the effect of factors. Physical characteristics, thermal pyrolysis temperature, and combustion time were considered as the properties. The amount of Al(OH)3 addition was chosen as significant parameter. As the result of ANOVA analysis, thermal pyrolysis temperature increased and combustion time decreased with increasing of Al(OH)3.