Boron carbide (B4C) is highly significant in the production of lightweight protective materials when added to aluminum owing to its exceptional mechanical properties. In this study, a method for fabricating Al-B4C composites using high-energy ball milling and directed energy deposition (DED) is presented. Al-4 wt.% B4C composites were fabricated under 21 different laser conditions to analyze the microstructure and mechanical properties at different values of laser power and scan speeds. The composites fabricated at a laser power of 600 W and the same scan speed exhibited the highest hardness and generated the fewest pores. In contrast, the composites fabricated at a laser power of 1000 W exhibited the lowest hardness and generated a significant number of large pores. This can be explained by the influence of the microstructure on the energy density at different values of laser power.

Porous Cu-14 wt% Co with aligned pores is produced by a freeze drying and sintering process. Unidirectional freezing of camphene slurry with CuO-Co3O4 powders is conducted, and pores in the frozen specimens are generated by sublimation of the camphene crystals. The dried bodies are hydrogen-reduced at 500oC and sintered at 800oC for 1 h. The reduction behavior of the CuO-Co3O4 powder mixture is analyzed using a temperature-programmed reduction method in an Ar-10% H2 atmosphere. The sintered bodies show large and aligned parallel pores in the camphene growth direction. In addition, small pores are distributed around the internal walls of the large pores. The size and fraction of the pores decrease as the amount of solid powder added to the slurry increases. The change in pore characteristics according to the amount of the mixed powder is interpreted to be due to the rearrangement and accumulation behavior of the solid particles in the freezing process of the slurry.

The hydrogen reduction behavior of the CuO-Co3O4 powder mixture for the synthesis of the homogeneous Cu-15at%Co composite powder has been investigated. The composite powder is prepared by ball milling the oxide powders, followed by a hydrogen reduction process. The reduction behavior of the ball-milled powder mixture is analyzed by X-ray diffraction (XRD) and temperature-programmed reduction at different heating rates in an Ar-10%H2 atmosphere. The scanning electron microscopy and XRD results reveal that the hydrogen-reduced powder mixture is composed of fine agglomerates of nanosized Cu and Co particles. The hydrogen reduction kinetics is studied by determining the degree of peak shift as a function of the heating rate. The activation energies for the reduction of the oxide powders estimated from the slopes of the Kissinger plots are 58.1 kJ/mol and 65.8 kJ/mol, depending on the reduction reaction: CuO to Cu and Co3O4 to Co, respectively. The measured temperature and activation energy for the reduction of Co3O4 are explained on the basis of the effect of pre-reduced Cu particles.

In this study, porous Mo-5 wt% Cu with unidirectionally aligned pores is prepared by freeze drying of camphene slurry with MoO3-CuO powders. Unidirectional freezing of camphene slurry with dispersion stability is conducted at -25℃, and pores in the frozen specimens are generated by sublimation of the camphene crystals. The green bodies are hydrogen-reduced at 750℃ and sintered at 1000℃ for 1 h. X-ray diffraction analysis reveals that MoO3- CuO composite powders are completely converted to a Mo-and-Cu phase without any reaction phases by hydrogen reduction. The sintered bodies with the Mo-Cu phase show large and aligned parallel pores to the camphene growth direction as well as small pores in the internal walls of large pores. The pore size and porosity decrease with increasing composite powder content from 5 to 10 vol%. The change of pore characteristics is explained by the degree of powder rearrangement in slurry and the accumulation behavior of powders in the interdendritic spaces of solidified camphene.

W-10 wt% Ti alloys that have a homogeneous microstructure are prepared by thermal decomposition of WO3-TiH2 powder mixtures and spark plasma sintering. The reduction and dehydrogenation behavior of WO3 and TiH2 are analyzed by temperature programmed reduction and a thermogravimetric method, respectively. The X-ray diffraction analysis of the powder mixture, heat-treated in an argon atmosphere, shows W- oxides and TiO2 peaks. Conversely, the powder mixtures heated in a hydrogen atmosphere are composed of W, WO2 and TiO2 phases at 600 ℃ and W and W-rich β phases at 800 ℃. The densified specimen by spark plasma sintering at 1500 ℃ in a vacuum using hydrogen-reduced WO3-TiH2 powder mixtures shows a Vickers hardness value of 4.6 GPa and a homogeneous microstructure with pure W, β and Ti phases. The phase evolution dependent on the atmosphere and temperature is explained by the thermal decomposition and reaction behavior of WO3 and TiH2.

This study analyzed population density changes and taxonomic characteristics of various microorganisms, which play important roles in culture medium fermentation of Agaricus bisporus and examined changes in decompositionrelated enzyme activity secreted by these microorganisms. Various microorganisms such as thermophilic bacteria, actinomycetes, fluorescent pseudomonas spp. and filamentous bacteria are closely related to culture medium fermentation of Agaricus bisporus. The population density of these microorganisms changes and harmful bacteria disappear during thermophilic fermentation. During outdoor fermentation, Psychrobacter sp., Pseudomonas sp., Bacillus sp. and Pseudoxanthomonas sp. showed the highest percentage distribution in the different culture medium while Bacillus sp. and Psychrobacillus sp. were the most dominant after pasteurization. When analyzing the enzyme activity of microorganism during rice straw fermentation, cellulose enzymes become important at the early stage of fermentation. Increase in hemicellulose enzyme follows after decomposing carbon sources. The microorganisms that secretes these enzymes were distributed at the second and third turning stage of fermentation.

The button mushroom, Agaricus bisporus, is one of the major economical crops cultivated in Korea. This mushroom showed the 5th production to 11,493 M/T in 2014. Several fungus are known as the causal agents of diseases of the cultivated button mushroom (Agaricus bisporus) and oyster mushroom (Pleurotus ostreatus). Cladobotryum mycophilum is the causal agent of cobweb disease of commercial mushrooms. Early symptoms were noticed as round, fleshy, yellowish brown lesions on mushroom caps. Late symptoms progressed when the parasitic fungus formed white cobweb circular colonies on dead or damaged pinheads, spread on the surface of the casing, and covered entirely fruiting bodies. A Gram-positive bacterium was isolated from mushroom media that markedly showed the antagonistic activity against Cladobotryum mycophilum, the most destructive pathogen of cultivated mushrooms. The HC57 strain was selected as antagonistic bacterium by inhibition zone method and it was identified as Bacillus subtilis by the cultural, morphological and physiological characteristics, and analysis of the 16S rDNA. The isolated bacterium is saprophytic but not parasitic nor pathogenic to cultivation mushroom. The isolated bacterium for Cladobotryum mycophilum cell, was sufficient for inhibition in vitro. Inoculation of the isolated bacterium prevents the development of bacterial disease in Cladobotryum mycophilum. Control efficacy of browning disease of strain HC57 treatment was 71% on Agaricus bisporus. The optimal culture medium for the antagonistic bacteria growth was determined as follows: 1.5% Xylose, 2% Soytone, 1% NH4H2PO4, 7 mmol CaCl2, and 0.5% Histidine at pH 6.0 at 25℃. The suppressive bacterium may be useful in future for the development of biocontrol system and the construction of genetically modified edible fungi resistant to the disease caused by Cladobotryum mycophilum.

This study was carried out to investigated optimum additive ratio of barley flour for substitution of rice bran atcultivation of winter mushrooms. Mycerial growth was faster according to increase of barley flour ratio than those of controls, butonly some slow at the addition of 10% barley flour. Yields of fruiting body show the highest to 165.4g/850ml of medium whichare the addition 30% of barley flour and not significant difference of yields up to the addition of 70% barley flour. Diameter ofpileus was the highest at the addition of 30% barley flour. Hardness of pileus and stipes were the highest at the addition of 10%barley flour. The L value of stipes were the hight at the addition of barley flour, but the L value of pileus were decreased at theaddition of barley flour, but there was no significant difference in the a-value and the b-value.

This study was carried out to investigated optimum mixing ratio of Korean cultivation Salvia miltiorrhiza forproduction of functional oyster mushroom. Mycerial growth was slow at addition of Salvia miltiorrhiza, and significant differenceby increase of Salvia miltiorrhiza. Yields of fruiting body show the highest to 139.5g/850ml of medium which are addition 5g/bottle of Salvia miltiorrhiza but rapid decrease by increase of Salvia miltiorrhiza. Diameter of pileus and thick of stipes were higherat addition Salvia miltiorrhiza than those of the controls. Thick of pileus and length of stipes were the highest at addition 30g, and20g and 30g of Salvia miltiorrhiza. The L value of stipes were the highest at addition 20g and 50g of Salvia miltiorrhiza and theL value of pileus were the highest at addition 30g of Salvia miltiorrhiza, but there was no significant difference in the a-value andthe b-value.

버섯 세균갈성색무늬병원균인 Pseudomonas tolaasii에 대한 길항미생물로 보고된 Pseudomonas azotoformans HC5 균주의 배양적 특성과 대량 배양을 위한 최적배양조건을 설정하였다. HC5 균주의 생육온도는 10~20oC, pH는 6.0~9.0의 범위에서 왕성한 생육을 보였다. 대량배양을 위한 효율적인 영양원 선발을 위하여 기본배지에 탄소원 fructose 등 18종, 무기질소원 NH4Cl 등 6종, 유기질소원 peptone 등 6종 그리고 아미노산 asparagine 등 11종을 각각 1%씩 첨가하였고, 무기염류 13종을 1 mM 농도로 첨가하여 각각에 대한 생육에 미치는 영향을 조사하였다. 또한 선발된 각각의 영양성분들에 대한 최적 농도를 조사하기 위하여 각각의 성분을 최소 0.1%에서 최대 4.0%까지 배지에 첨가하여 배양 후 생육정도를 조사하였다. 그 결과, 대량배양을 위한 생육최적조건은 온도 15oC, pH 6, 탄소원 0.6% adonitol, 유기질소원 1.5% yeast extract, 무기질소원 0.8% NH4H2PO4,아미노산 0.2% asparagine 그리고 무기염류는 5 mM MgSO4에서 왕성한 생육을 보였다.

장기기증은 장기부전환자를 위한 최선의 치료방법임에도 불구하고 국내의 기증비율은 무척 낮은 편이다. 장기기증에 대한 지식과 태도를 개선하여 장기기증 의향과 실천으로 연결시키는 효과적 교육과 대중의 인식이 요구된다. 이에 본 연구는 일(一) 간호대학생의 장기기증에 대한 지식 및 태도를 포함한 비판적 사고 성향을 알아보고, 학년 간 차이 및 상관성을 분석하여 장기기증에 대한 교육과 참여 활성화에 기여하고자 한다. 비판적 사고 성향 측정도구는 총 27문항, 장기기증에 대한 지식 측정도구는 총 17문항, 태도 측정도구는 긍정적 태도 29문항과 부정적 태도 16문항으로 이루어졌다. 총 대상자 352명(1학년 208명, 3학년 144명)의 평균나이는 20.74세(±2.86)였고, 전공간호학 교육과 임상실습경험이 있는 3학년(12.56±1.86, 68.5%)이 1학년(11.64±2.08, 73.9%)보다 장기기증에 대해 높은 수준의 지식(p<.001)과 긍정적인 태도(p=.002)를 가지고 있었다. 한편, 비판적 사고 성향이 증가할수록 장기기증에 대해 높은 지식수준(r=0.126, p=.018)과 긍정적인 태도(r=.113, p=.034)를 보였으나, 학년 간 교육정도에 따른 비판적 사고 성향에서는 유의미한 차이를 보이지는 않았다(p=.739). 그러나 장기기증에 대한 지식과 태도가 정적인 상관관계를 보이며(r=0.117, p=.030), 장기기증 의향에 따라 장기기증 태도의 차이가 유의하게 나타났다(p<.001). 따라서 장기기증에 대한 윤리적 태도에 초점을 둔 간호교육을 통해 장기기증 인식 변화를 꾀할 수 있을 것으로 기대된다. 생명의료 윤리의식은 비판적 사고를 통해 도덕적 차원의 검토를 실행하는 것이라고 할 때, 비판적 사고의 함양을 통해 장기기증에 대한 윤리적 태도와 지식을 고취할 수 있는 교육을 시행해야 할 것이다.

Mushroom is cultivated as one of the major economical crops in many areas in Korea. The total production has steadily increased from approximately 198,563 M/T in 2009 to 208,941 M/T in 2012. Several fungus are known as the causal agents of diseases of the cultivated button mushroom (Agaricus bisporus) and oyster mushroom (Pleurotus ostreatus). Trichoderma harzianum is the causal agent of brown blotch disease of commercial mushrooms. Colonization of mushroom caps by the bacterium results in development of brown or cream lesions on pileus and stipe. These lesions are slightly concave spots and can be round or spreading. Antagonists against Trichoderma harzianum, CAM33 were selected and their control efficacy of green mould disease was investigated in this study. The CAM33 strain was selected as antagonistic bacterium by inhibition zone method and it was identified as Bacillus methyrotrophicus. by the cultural, morphological and physiological characteristics, and analysis of the 16S rDNA. The isolated bacterium is saprophytic but not parasitic nor pathogenic to cultivation mushroom. The isolated bacterium for Trichoderma harzianum cell, was sufficient for inhibition in vitro. Inoculation of the isolated bacterium prevents the development of bacterial disease in Trichoderma harzianum. Control efficacy of browning disease of strain CAM33 treatment was 77% on Agaricus bisporus. The optimal culture medium for the antagonistic bacteria growth was determined as follows: 3.0% Saccharose, 1.5% Soytone, 1.0% (NH4)2HPO4, 10 mmol MgSO4, and 2.0% Glutamic acid at pH 6.0 at 25°C. The suppressive bacterium may be useful in future for the development of biocontrol system and the construction of genetically modified edible fungi resistant to the disease caused by Trichoderma harzianum.

The button mushroom, Agaricus bisporus, is one of the major economical crops cultivated in Korea. This mushroom showed the 5th production to 10,996 M/T in 2012. Several fungus are known as the causal agents of diseases of the cultivated button mushroom (Agaricus bisporus) and oyster mushroom (Pleurotus ostreatus). Cladobotryum mycophilum is the causal agent of cobweb disease of commercial mushrooms. Early symptoms were noticed as round, fleshy, yellowish brown lesions on mushroom caps. Late symptoms progressed when the parasitic fungus formed white cobweb circular colonies on dead or damaged pinheads, spread on the surface of the casing, and covered entirely fruiting bodies. A Gram-positive bacterium was isolated from mushroom media that markedly showed the antagonistic activity against Cladobotryum mycophilum, the most destructive pathogen of cultivated mushrooms. The HC7 strain was selected as antagonistic bacterium by inhibition zone method and it was identified as Bacillus altitudinis. by the cultural, morphological and physiological characteristics, and analysis of the 16S rDNA. The isolated bacterium is saprophytic but not parasitic nor pathogenic to cultivation mushroom. The isolated bacterium for Cladobotryum mycophilum cell, was sufficient for inhibition in vitro. Inoculation of the isolated bacterium prevents the development of bacterial disease in Cladobotryum mycophilum. Control efficacy of browning disease of strain HC7 treatment was 78% on Agaricus bisporus. The optimal culture medium for the antagonistic bacteria growth was determined as follows: 3% Soluble startch, 10% Soytone, 1% (NH4)2HPO4, 1 mmol KCl, and 0.5% L-asparagin at pH 6.0 at 30°C. The suppressive bacterium may be useful in future for the development of biocontrol system and the construction of genetically modified edible fungi resistant to the disease caused by Cladobotryum mycophilum.

The button mushroom, Agaricus bisporus, is one of the major economical crops cultivated in Korea. This mushroom showed the 5th production to 10,996 M/T in 2012. Several bacteria are known as the causal agents of diseases of the cultivated button mushroom (Agaricus bisporus) and oyster mushroom (Pleurotus ostreatus). Pseudomonas agarici is the causal agent of browning disease of commercial mushrooms. Colonization of mushroom caps by the bacterium results in development of browning lesions on pileus. These lesions are superficial brown spots and can be round or spreading. But P. agarici never caused sunken lesions and rotting of the mushroom tissues. A Gram-positive bacterium was isolated from mushroom media that markedly showed the antagonistic activity against Pseudomonas agarici, the most destructive pathogen of cultivated mushrooms. The HC42 strain was selected as antagonistic bacterium by inhibition zone method and it was identified as Bacillus safensis. by the cultural, morphological and physiological characteristics, and analysis of the 16S rDNA.. The isolated bacterium is saprophytic but not parasitic nor pathogenic to cultivation mushroom. The isolated bacterium for P. agarici cell, was sufficient for inhibition in vitro. Inoculation of the isolated bacterium prevents the development of bacterial disease in Agaricus bisporus. Control efficacy of browning disease of strain HC42 treatment was 66% on Agaricus bisporus. The optimal culture medium for the antagonistic bacteria growth was determined as follows: 1.5% D-galactose, 1.5% yest extract, 1% NH4Cl, 1.5% KCl, and 1.0% L-asparagin at pH 6.0 at 25℃. The suppressive bacterium may be useful in future for the development of biocontrol system and the construction of genetically modified edible fungi resistant to the disease caused by P. agarici.

Mushroom is cultivated as one of the major economical crops in many areas in Korea. The total production has steadily increased from approximately 186,400 M/T in 2007 to 190,111 M/T in 2011. The button mushroom, Agaricus bisporus, showed the 5th production to 13,052 M/T in 2011. Several bacteria are known as the causal agents of diseases of the cultivated button mushroom (Agaricus bisporus) and oyster mushroom (Pleurotus ostreatus). Pseudomonas agarici is the causal agent of browning disease of commercial mushrooms. Colonization of mushroom caps by the bacterium results in development of browning lesions on pileus. These lesions are superficial brown spots and can be round or spreading. But P. agarici never caused sunken lesions and rotting of the mushroom tissues. Antagonists against P. tolaasii, HC42 were selected and their control efficacy of browning disease was investigated in this study. Antagonists against P. agarici, HC42 were selected and their control efficacy of browning disease was investigated in this study. After proceeding antagonistic test, HC42 was selected as a strong antagonist against P. agarici and the HC42 strain was identified as P. safensis with the cultural, physiological and biochemical properties and analysis of the 16S rRNA. The optimal culture medium for the antagonistic bacteria growth was determined as follows: 1.5% D-galactose, 1.5% yest extract, 1% NH4Cl, 1.5% KCl, and 1.0% L-asparagin at pH 6.0 at 25℃. Control efficacy of browning disease by HC42 treatment was 66% on Agaricus bisporus..

Mushroom is cultivated as one of the major economical crops in many areas in Korea. The total production has steadily increased from approximately 186,400 M/T in 2007 to 190,111 M/T in 2011. The button mushroom, Agaricus bisporus, showed the 5th production to 13,052 M/T in 2011. Several bacteria are known as the causal agents of diseases of the cultivated button mushroom (Agaricus bisporus) and oyster mushroom (Pleurotus ostreatus). Pseudomonas agarici is the causal agent of browning disease of commercial mushrooms. In this study, antagonistic bacteria to P. agarici were selected in vitro tests using confrontation bioassay and paper disk diffusion assay. The most active bacteria, HC12 were selected and their control efficacy of brown blotch disease was investigated in this study. After proceeding antagonistic test, HC12 was selected as a strong antagonist against P. agarici and the HC12 strain was identified as Alcaligenes sp. with the cultural, physiological and biochemical properties and analysis of the 16S rRNA. The optimal culture medium for the antagonistic bacteria growth was determined as follows: 0.5% dextrin, 1.5% yest extract, 1% NaNO3, 0.5% KH2PO4, and 1.5% L-asparagin at pH 9.0 at 30℃. Control efficacy of browning disease by HC12 treatment was 63% on Agaricus bisporus..

Mushroom is cultivated as one of the major economical crops in many areas in Korea. The total production has steadily increased from approximately 186,400 M/T in 2007 to 190,104 M/T in 2009. The oyster mushroom, Pleurotus ostreatus, showed the 2th production to 46,598 M/T in 2011. This study was carried out to investigated optimum mixing ratio of Korean natural Acer tegmentosum for production of functional oyster mushroom. Mycelial growth of Pleurotus ostreatus showed the highest growth at the media of 10% Acer tegmentosum and was decreased to increase of Acer tegmentosum addition ratio. But mushroom mycelial growth at Acer tegmentosum media was slower than that of the control. Total nitrogen and carbon source of Acer tegmentosum was 0.19% and 44.4%, respectively and C/N ratio was 234. Total nitrogen source and pH of substrates mixed with Acer tegmentosum were 2.7∼3.0 and 4.8∼5.0, respectively. The contents of P2O5 and K2O were decreased by increasing Acer tegmentosum but the contents of CaO, MgO and Na2O were no significant difference. The contents of Fe and Mn were decreased according to increasing of Acer tegmentosum, but the contents of Zn and Mn were no significant difference. Yields of fruiting body and diameter and thick of pileus were the highest at 10% Acer tegmentosum. The L value of pileus was the highest at the 30% Acer tegmentosum during mushroom harvest, but there was no significant difference in the a-value and the b-value. The contents of P2O5,, CaO, MgO and Na2O of fruiting body were no significant difference, but contents of Cu was decreased and Fe was increased according to increasing of Acer tegmentosum.