• 미생물학회지
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• 제46권3호
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• pp.270-277
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• 2010

장류 제조에 Bacillus cereus의 오염을 줄이기 위한 방법으로 전국 150 종 장류에서 분리한 무독소 Bacillus subtilis 및 Bacillus licheniformis 균들을 대상으로 B. cereus에 대해 억제능력이 큰 한 균주 SCK 121057를 선발하였다. SCK 121057은 생화학 검사 및 16S rRNA 유전자 서열에 의한 계통도 분석 결과 B. licheniformis로 동정되었고 12 종의 B. cereus 이외에 중요 병원성 균인 Staphylococcus aureus, Aspergillus flavus, A. ochraceus, A. parasiticus 등의 증식을 억제하였다. SCK 121057이 생산하는 항균 물질은 고압멸균 조건에서 열안정성, proteinase K에 대한 가수 분해 저항성, $37^{\circ}C$에서 장기 저장성을 지닌 구조적으로 매우 안정한 물질이었고, 전자현미경 관찰에서 이 물질은 B. cereus의 세포막을 손상시켜 ghost cell을 형성하였다. SCK 121057 균과 B. cereus를 혼합 접종한 청국장 적용 실험 결과 B. cereus 균수는 대조군에 비해 극적으로 감소되었다.

• International Journal of Industrial Entomology and Biomaterials
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• 제8권1호
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• pp.27-32
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• 2004

With an objective of evolving quantitatively and qualitatively superior bivolitine silkworm hybrid of Bombyxmori L. for tropics with shorter larval duration without compromising on productivity traits, a breeding programme was initiated at this institute during 1997 by utilizing breeding resource material from the institutes Germplasm collection. The breed SD7 is characterized with plain larvae spinning white oval cocoons and SD12 is characterized by sex-limited larval markings spinning white dumb-bell cocoons. After fixation, these breeds along with other newly evolved breeds were subjected for hybrid evaluation in the laboratory. Based on the hybrid studies, the hybrid SD7${\times}$SD12 was selected and evaluated for one year comprising three major sea- sons (6 trials) of tropics viz., Pre-monsoon (characterized by high temperature, low humidity and without any rain fall), Monsoon (characterized by moderate temperature, heavy rain fall with high humidity) and post-monsoon season (characterized by low temperature and low humidity with frequent rain fall) to know the fluctuations in the larval duration. The evaluation studies indicated that the hybrid is having shorter larval duration with productive merits. The hybrid SD7${\times}$SD12 recorded survival percent of 92.74, shell weight of 46.7 cg, shell ratio % of 24.0 and filament length of 1,200 meters with a shorter larval duration of 24 hrs; when compared to productive hybrid CSR2${\times}$CSR5(control). The breeding methodologies and hybrids usefulness for tropics were discussed.

• Advances in nano research
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• 제5권3호
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• pp.261-279
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• 2017

Spectroscopic investigation of Si quantum dots (Si-QDs) embedded in silicon nitride was performed over a broad stoichiometry range to optimize light emission. Plasma-enhanced chemical vapor deposition was used to grow the $SiN_x$ films on Si (001) substrates. The film composition was controlled via the flow ratio of silane ($SiH_4$) and ammonia ($NH_3$) in the range of R = 0.45-1.0 allowed to vary the Si excess in the range of 21-62 at.%. The films were submitted to annealing at $1100^{\circ}C$ for 30 min in nitrogen to form the Si-QDs. The properties of as-deposited and annealed films were investigated using spectroscopic ellipsometry, Fourier transform infrared spectroscopy, Raman scattering and photoluminescence (PL) methods. Si-QDs were detected in $SiN_x$ films demonstrating the increase of sizes with Si excess. The residual amorphous Si clusters were found to be present in the films grown with Si excess higher than 50 at.%. Multi-component PL spectra at 300 K in the range of 1.5-3.5 eV were detected and nonmonotonous varying total PL peak versus Si excess was revealed. To identify the different PL components, the temperature dependence of PL spectra was investigated in the range of 20-300 K. The analysis allowed concluding that the "blue-orange" emission is due to the radiative defects in a $SiN_x$ matrix, whereas the "red" and "infrared" PL bands are caused by the exciton recombination in crystalline Si-QDs and amorphous Si clusters. The nature of radiative and no radiative defects in $SiN_x$ films is discussed. The ways to control the dominant PL emission mechanisms are proposed.

• 한국환경과학회지
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• 제18권12호
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• pp.1339-1347
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• 2009

This study tried to investigate and analyze the actual state such as the regional, classified, and material characteristics of the water quality in order to research the several factors by which the filtrated water of the total 250 cases can be polluted in the water tank. The 215 points (86%) clean the water tanks twice a year regularly and J-city has done the best job of cleaning the water tanks. The fifty points (20%) of the total 250 investigation points examine the water quality of the water tanks every year, however, the 175 investigation points (70%) do not execute the inspection of water quality. In the case of the regional characteristics in the water quality, the 23 points (46%) in H-county, the 17 points (34%) in S-county, and the 16 points (32%) in G-city are incongruent in the standard, and the incongruity ratio of the water quality in J-city is the lowest. The result of the classified incongruity shows that total coliforms were found at the 61 investigation points, mesophilic bacteria were found at the 27 points, and turbidity was found at the 12 points. In the case of the material incongruity, concrete was found at the 63 investigation points as the most distinguished factor, and FRP (fiberglass reinforced plastic) at the 23 points, SMC (sheet molding compound) at the 12 points, and stainless steel was found at the 2 points.

• Asian-Australasian Journal of Animal Sciences
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• 제26권6호
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• pp.864-873
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• 2013

In developing countries, biogas energy production is seen as a technology that can provide clean energy in poor regions and reduce pollution caused by animal manure. Laboratories in these countries have little access to advanced gas measuring equipment, which may limit research aimed at improving local adapted biogas production. They may also be unable to produce valid estimates of an international standard that can be used for articles published in international peer-reviewed science journals. This study tested and validated methods for measuring total biogas and methane ($CH_4$) production using batch fermentation and for characterizing the biomass. The biochemical methane potential (BMP) ($CH_4$ NL $kg^{-1}$ VS) of pig manure, cow manure and cellulose determined with the Moller and VDI methods was not significantly different in this test (p>0.05). The biodegradability using a ratio of BMP and theoretical BMP (TBMP) was slightly higher using the Hansen method, but differences were not significant. Degradation rate assessed by methane formation rate showed wide variation within the batch method tested. The first-order kinetics constant k for the cumulative methane production curve was highest when two animal manures were fermented using the VDI 4630 method, indicating that this method was able to reach steady conditions in a shorter time, reducing fermentation duration. In precision tests, the repeatability of the relative standard deviation (RSDr) for all batch methods was very low (4.8 to 8.1%), while the reproducibility of the relative standard deviation (RSDR) varied widely, from 7.3 to 19.8%. In determination of biomethane concentration, the values obtained using the liquid replacement method (LRM) were comparable to those obtained using gas chromatography (GC). This indicates that the LRM method could be used to determine biomethane concentration in biogas in laboratories with limited access to GC.

• Asian-Australasian Journal of Animal Sciences
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• 제24권3호
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• pp.407-413
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• 2011

Effect of dietary protein and lipid levels on compensatory growth of juvenile olive flounder (Paralichthys olivaceus) was determined in suboptimal temperature ($13.4{\pm}1.42^{\circ}C$). Five hundred forty fish averaging 79.2 g were randomly distributed into 27 of 300 L flow-through tanks (20 fish/tank). Nine treatments were prepared in triplicate: fish were hand-fed with control (C) diet for 10 weeks (10WF-C); four fish groups were starved for 1 week and then fed with C, high protein (HP), high lipid (HL) and combined high protein and high lipid (HPL) diets for 9 weeks, referred to as 9WF-C, 9WF-HP, 9WF-HL, 9WF-HPL, respectively; and other four fish groups were starved for 2 weeks and then fed with C, HP, HL and HPL diets for 8 weeks, referred to as 8WF-C, 8WF-HP, 8WF-HL and 8WF-HPL, respectively. Weight gain and specific growth rate of fish in 9WF-HP, 9WF-HPL, 8WF-HP and 8WF-HPL treatments were higher than those of fish in 9WF-HL and 8WF-HL treatments. Feed efficiency of fish in 8WF-HP treatment was higher than that of fish in 9WF-C, 9WF-HL and 8WF-HL treatments. Protein efficiency ratio of fish in 10WF-C, 8WF-C, 8WF-HP and 8WF-HPL treatments was higher that that of fish in 9WF-HL and 8WF-HL treatments. Juvenile olive flounder subjected to 2-week feed deprivation could achieve full compensatory growth with dietary supplementation of protein or combined high protein and high lipid.

• Asian-Australasian Journal of Animal Sciences
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• 제20권3호
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• pp.399-404
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• 2007

To elucidate the efficacy of different levels of microbial-fermented soy proteins (FSP) on piglet performance, a total of 240 weaned piglets ($L{\times}Y{\times}D$, $22{\pm}3$ d of age, $5.16{\pm}0.07$ kg initial BW) were allotted to 4 treatment diets comprising control, FSP-3%, FSP-6% and FSP-9%. The fermented soybean product named $Pepsoygen^{(R)}$ was utilized for the study. There were 15 pigs per pen and 4 pens per treatment. The control diet contained 15% soybean meal (SBM), and SBM for the treatment diets was replaced at 3, 6 and 9% with FSP, respectively. Experimental diets were fed from 0 to 14 d (phase-I) after weaning and then a common commercial diet was fed from 15 to 35 d (phase-II). There was a linear (p<0.05) increase in ADG and ADFI at both phases of measurement. The feed to gain ratio was also improved, showing a linear (p<0.01) trend as the level of supplementation increased. Except for phosphorus, the digestibility of all other nutrients was improved linearly (p<0.05) in the FSP added diets. However, villous height and crypt depth were not affected by dietary treatments. No special effect on intestinal morphology was noticed between FSP-added and control diets. In conclusion, the growth, digestibility of nutrients and morphological changes in weaned pigs fed FSP showed improved performance at higher levels of supplementation.

• Geomechanics and Engineering
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• 제14권4호
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• pp.367-376
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• 2018

Samples composed of coal and rock show different mechanical properties of the pure coal or rock mass. For the same coal seam with different surrounding rocks, the frequency and intensity of rock burst can be significantly different in. First, a method of measuring the strain variation of coal in the coal-rock combined sample was proposed. Second, laboratory tests have been conducted to investigate the influences of rock lithologies, combined forms and coal-rock height ratios on the deformation and failure characteristics of the coal section using this method. Third, a new bursting liability index named combined coal-rock impact energy speed index (CRIES) was proposed. This index considers not only the time effect of energy, but also the influence of surrounding rocks. At last, a new approach considering the influences of roof and/or floor was proposed to evaluate the impact capability of coal seam. Results show that the strength and elastic modulus of coal section increase significantly with the coal-rock height ratio decreasing. In addition, the values of bursting liability indexes of the same coal seam vary greatly when using the new approach. This study not only provides a new approach to measuring the strain of the coal section in coal-rock combined sample, but also improves the evaluation system for evaluating the impact capability of coal.

• 한국식품조리과학회지
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• 제30권3호
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• pp.333-339
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• 2014

The purpose of this study was to evaluate the quality properties of muffin added with different concentration (0, 1, 3, and 5%) of ginseng leaves powder, which is discarded in the process of ginseng. Density of muffin was the highest at 1.45 g/mL in control, and pH (7.41) was at the highest level as well. There was no tendency at the bottom and upper dimensions according to addition of ginseng leaf powder. The height and baking loss rate of the muffins increased with increase in the powder concentration, but there were no significant differences. The weight of muffins did not show constant tendency, according to addition ratio of ginseng leaves powder. The degree of lightness and yellowness of muffin decreased as the concentration of the powder increased, whereas no significant difference in the redness was found with increased powder concentration. The factors of hardness and chewiness were higher at the control group and cohesiveness was the highest at 0.65 in 3% group, but springiness and gumminess did notshow significant differences. DPPH free radical scavenging activity of muffins was significantly increased with increasing ginseng leaves powder (p<0.05). For the sensory evaluation in 1% group, the intensity of color, smell, taste, softness, and moistness was the lowest, whereas the overall acceptability score of color, smell, taste, chewiness, and moistness was the highest. Thesensory properties of muffin linearly decreased as the concentration of ginseng leaves powder increased. Taken together, the results of this study suggest that ginseng leaf powder is a good ingredient for increasing the consumer acceptability and functionality of cookies.

• 한국수산과학회지
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• 제19권4호
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• pp.347-355
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• 1986

서낙동강의 강수는 김해평야에 농업 용수의 공급원으로서 뿐만아니라 수산 용수로서도 중요한 수계이다. 김해시민들에 의하여 배출되는 생활 오수, 김해평야에 살포되는 농약 등의 유입과 양대 수문에 의한 강수의 완만한 유동으로 서낙동강의 수역을 급속도로 오탁시킬 우려성을 갖고 있는 실정이다. 이들 수질 관리에 대한 기초자료를 얻고자 1985년 7월부터 12월까지 7회에 걸쳐 8회 지점에서 총 시료 56개로서 강수 수질의 일반성상, 영양염류와 오염지표세균에 대한 조사 결과를 보고하는 바이다. 1. pH의 변화범위와 평균치는 $6.3{\sim}9.4$, 7.91이었으며, 중${\cdot}$하부 수역에서 높은 수치를 나타내었다. 수온은 $6.1{\sim}34.8^{\circ}C,\;23.88^{\circ}C$였고, 전기전도도(지점 $A{\sim}G$)는 $1.575{\times}10^2{\sim}30.50{\times}10^2{\mu}{\mho}/cm$로서 하구로 향할수록 증가하였으며 지점 F에서는 조만 강수의 영향으로 희석되어 낮은 값을 나타내었다. 또, 강우가 빈번하였던 8,9월은 갈수기 보다 월등히 낮은 값을 나타내었다. 염화이온 농도의 변화범위와 평균치는 $23.5{\sim}14,300mg/l$, 770.0mg/l로서 지점별로 큰 폭으로 변하였다. 이 농도의 변화범위 및 평균치는 수문이 없는 낙동강의 경우 귀포 지점에서 보다는 높은 값이었다. 2. 영양염류중의 아질산성 질소의 변화범위는 평균치는 $0.007{\sim}0.110mg/l$, 0.053mg/l, 질산성 질소는 $0.001{\sim}1.638mg/l$, 0.649mg/l, 암모니아성 질소는 $0.017{\sim}4.200mg/l$, 0.497mg/l, 인산성 인은 $0.011{\sim}0.281mg/l$, 0.086mg/l, 규산성 규소는 $2.4{\sim}6.5mg/l$, 4.43mg/l로 각각 나타났다. 3. 대장균군 최확수는 $36{\sim}110,000/100ml$, 분편계대장균은 $15{\sim}46,000/100ml$, 그리고 장구균은 $3.6{\sim}15,000/100ml$이었으며, 특히 지점 B와 C오염이 극심하였다. T.C/F.C값의 범위와 평균치는 $3.0{\sim}9.6,5.51$이었으며, 분편계대장균의 오염률이 $21.26\%$이었다. 또, F.C/F.S 값의 범위와 평균치는 $1.1{\sim}9.2$, 6.19이었으며, 4.0이상인 지점이 $75\%$로서 미처이된 분편에 의하여 오염되어 있음을 시사하여 준다. 대장균군의 조성은 E.coli군이 $52\%$로 제일 많이 분류되었고, Enterobacter aerogenes군이 $13\%$, Citrobacter freundii군 순이었다.