• 기계와재료
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• v.20 no.4
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• pp.57-66
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• 2009

• Food Science and Preservation
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• v.22 no.2
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• pp.225-231
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• 2015

This study was conducted to examine the physicochemical properties and micro-encapsulation process of rice fermented with Bacillus subtilis CBD2. The viable bacterial cell, pH, and amylase activity of the rice liquid culture were 7.61 log CFU/mL, pH 5.08 and 159.43 units/mL, respectively. The micro-encapsulated rice liquid culture was manufactured via spray drying with different forming agents: i.e., alginic acid 1.0% and chitosan 0.3%, 0.5%, and 1.0%. The moisture contents of the spray-dried powders were approximately 2.90~3.68%. The color of the L and a value decreased whereas that of the b and ${\Delta}E$ value increased. The particle size and outer topology of the spray-dried rice liquid culture were $48.13{\sim}68.48{\mu}m$ and globular, respectively. The water absorption index of the spray-dried powder (2.40~2.65) was lower than that of the freeze-dried powder (2.66). The water solubility index of the spray-dried powder (9.17~10.89%) was higher than that of the freeze-dried powder (7.12%). The in vitro dissolution was measured for five hours in pH 1.2 simulated gastric fluid, and pH 6.8 and pH 7.4 simulated intestinal fluids, using a dissolution tester at $37^{\circ}C$ with 50 rpm agitation. The amylase survival in the fermented rice was 85.93% through the spray-drying and it was very effectively controlled.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2002.05a
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• pp.397-402
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• 2002

노즐을 통하여 미세한 물 입자를 뿜어내어 화재를 진압하는 방식은 1930년대부터 응용되어왔지만 하론이 소화 물질로서 개발되어 널리 사용됨에 따라 물분무에 대한 개발이 중단되었다. 그러나 몬트리올 환경회의에 의해 하론이 오존층 파괴 물질로 사용이 제한됨에 따라 대체 소화물질로서 1990년대에 미세 물분무에 대한 연구가 활발히 진행되기 시작하였으며 최근 IMO(세계 해사기구)에서는 2003년부터 건조되는 선박의 소화설비로서 물분무 노즐 사용을 의무화하기 시작했다.(중략)

• Journal of the Korea Convergence Society
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• v.12 no.1
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• pp.185-191
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• 2021

A powder metallurgy process with granules is the manufacturing technology that can achieve higher-density sintered parts than conventional powder metallurgy processes. However, there is a disadvantage in that the production cost increases significantly due to the additional granulation step. High granule productivity must be guaranteed for affordable material costs in this manufacturing technology. This paper performed a series of scattering, collision, and adhesion simulations of agglomerated powders to investigate the characteristics of granulation process affecting the manufacturing yield rate. The results of this simulation-based convergence study can contribute to improving productivity in the metal powder spray granulation process.

• Proceedings of the KIEE Conference
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• 2006.10a
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• pp.184-185
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• 2006

환경오염 등으로 최근 자주 발생하는 국지성 집중호우로 인해 건물 중에서 지하 변전실은 가장 먼저 침수가 발생하게 된다. 따라서 본 논문은 지하에 시설된 전기 설비 중 몰드 변압기의 표면이 수분과 같은 불순물에 의해 오염될 경우 절연물에 미치는 영향과 위험성을 알아보기 위한 것으로 건조 시와 수용액 분무 후에 대한 연면손상에 대해 연구하였다. 실험 장치는 고전압 발생장치, 전극, 촬영장치 등으로 구성되었으며, 실험 결과 불꽃의 형상은 건조 시에는 가늘고 강한 빛으로 거의 직선적이고, 수용액 분 후는 산발적으로 광범위하게 나타난다. 방전에 의한 연면손상 특성을 보면 건조 시와 수용액 분무 후 모두 전극 간격이 증가할수록 탄화의 흔적이나 손상의 정도가 감소함을 알 수 있었으며 전반적으로 수용액 분무 후는 건조 시 보다 탄화 및 손상의 정도가 낮은 반면 부위는 광범위한 것으로 나타났다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.1
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• pp.57-63
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• 1984

This study was designed to compare the quality characteristics of freeze and spray dried red ginseng extract powders(RGEPs) by drying methods, which have been required to maintain the stability for the quality. Chemical compositions, major ginsenoside contents and color intensities of these Products were compared by drying conditions. The moisture absorption rates and optical densities also were compared during storage under maltreatment conditions of a various relative humidities (75, 86and 92 RH) and two different temperatures (37 and $50^{\circ}C$). It was found that decreases of total major ginsenosides contents in freeze and spray dried RGEPs were 5.4 % to 6.7 % during storage for 6 months at $37^{\circ}C$, 75 % RH. When these products packaged with inner seal of Al-foil laminate paper (Al-foil; 9 ${\mu}m$) were stored for 6 months at $37^{\circ}C$, 75 % RH. the moisture absorption rates of freeze and spray dried RGEPs were ranged 42 % to 82 %, 8 % to 16 %, respectively. In storage for 6 months at $37^{\circ}C$, 86 % RH, spray dried RGEP was higher in brown pigment($400{\sim}490nm$) than freeze dried RGEP while freeze dried was higher in pyrazine (278 nm), HMF and furfural (285 nm) than spray dried RGEP. It was found that RGEPs showed a strong anti-oxidative activity by electron donating ability to DPPPH, but there was no significant difference between freeze and spray dried RGEPs.

• Journal of the Korean Ceramic Society
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• v.39 no.5
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• pp.446-451
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• 2002

Zirconia/alumina mixture powder was spray-dried various degree of dispersion, type of dispersants and powder content in the slurry. The quality of the granule was determined by observation of the granule shapes after spray drying and fracture of intergranular boundaries during pressing. Defect-free granules were obtained from the powders that formed weak flocs in the slurry. The granules, spray-dried from the slurry containing 32.5 vol% powder mixture and PVP as binder, were fractured completely during shaping and the sintered specimens showed a density of 99.7% and a flexural strength of 850 MPa.

• Korean Journal of Materials Research
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• v.7 no.12
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• pp.1027-1032
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• 1997

본 연구에서는 용사용WC-17%Co 복합분말을 분무건조법으로 제조하고 열처리 온도(85$0^{\circ}C$, 100$0^{\circ}C$, 115$0^{\circ}C$, 130$0^{\circ}C$)에 따른 조립분말의 미세구조, 입도분포, 유동도, 및 결정상변화를 고찰하였다. 분무건조상태의 입형은 구형이었으며, 입도분포, 평균입자크기, 유동성은 각각 20.6-51.7$\mu\textrm{m}$, 27.2$\mu\textrm{m}$, 0.26 sec/g 이었다. 열처리에 의하여 조립분말은 치밀화되어 130$0^{\circ}C$ 열처리 후에는 입도분포와 평균입자크기가 각 각 6.9-37.9$\mu\textrm{m}$과 17.8$\mu\textrm{m}$로 감소하였으며, 유동성은 0.12 sec/g로 향상되었다. 열처리중에 WC와 Co의 상화확산에 의하여 Co$_{6}$W$_{6}$C및 Co$_{3}$W$_{3}$C이 생성되었으며, 두 상이 나타나는 임계온도는 115$0^{\circ}C$이었다.

• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1589-1595
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• 1999

Reverse osmosis(RO) and rotary evaporation, freezer drying and spray drying as concentration and dehydration methods were, respectively, employed to investigate their effect on the flavor quality of ginger powder. Rotary evaporation and spray drying methods were more effective to restrict the browning of ginger powder than RO and freezer drying methods. Concentration methods had no effect on the free amino acids and free sugar contents of ginger powder, but freezer drying resulted in the less quality loss than spray drying. And the powder prepared from enzymatically hydrolyzed extract contained less crude protein, crude ash, browning and the changes in free amino acids, but had more the crude fat, solubility and free sugars than that from ginger extract obtained by filter press. Sensory results indicated that quality of ginger powder prepared by RO concentration and freeze drying of enzymatically hydrolyzed extract was as good as that without enzyme hydrolysis

• Applied Chemistry for Engineering
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• v.26 no.5
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• pp.549-556
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• 2015

Anti-insect repellent silica sol from mixture with silica and anti-insect repellent solution extracted from medicinal herbs was prepared. The micron size porous sphere powder with anti-insect repellent solution was prepared by the spray drying method. The characteristic of anti-insect repellent powder using spray drying method was analyzed by FE-SEM, PSA, TGA with the concentration of anti-insect repellent sol (anti-insect repellent solution and silica) and conditions of spray drier. The average particle size of 4, 7 wt% and 10 wt% of anti-insect repellent sol concentration were 8.3, $9.5{\mu}m$ and $11.7{\mu}m$, respectively. The particle size is increasing with high concentration of anti-insect repellent sol. Other hands, particle size as the temperature of inlet nozzle and velocity of sol injection were nearly same at high velocity of gas injection. Also, Anti-insect repellent impregnation in porous sphere powder were confirmed by TGA methode and its thermal property was stable up to $200^{\circ}C$. We expect that anti-insect repellent powder is applied for plastic compound and process of film manufacture.