Wheel 형 분무건조기에서 반응표면법에 의한 치즈 분말의 특성 해석

강안수,여경목,김용렬,김복남,안형환,이한섭 ( An Soo Kang,Kyung Mok Yeo,Yong Ryeol Kim,Bok Nam Kim,Hyung Hwan An,Han Seob Lee ) 한국공업화학회 1996 공업화학 Vol.7 No.6

Wheel형 분무건조기에서 식품첨가제로 사용되는 치즈분말의 건조공정을 반응표면법에 의하여 원료의 고형분함량, wheel 회전속도 및 출구온도를 독립변수로 하고 분말제품의 수분함량, 겉보기밀도, 분말 입자크기 및 현탁액의 점도를 종속변수로 하여 중심합성계획법에 따라 분산분석한 후 유의성과 상관관계을 검증하였다. 독립변수와 종속변수들의 상관관계를 검증한 결과 입자크기와 수분함량은 wheel의 회전속도가 커질수록 감소하였고, 겉보기밀도는 출구온도가 높아짐에 따라 감소하였다. 현탁액의 점도는 wheel의 회전속도와 고형분함량이 커짐에 따라 증가하였다. 분말제품의 종속변수들의 상관관계에서 수분함량과 겉보기밀도는 비례 관계, 입자크기는 수분함량과 걸보기밀도와 반비례의 관계를 나타내었다. In the spray drying with rotating wheel atomizer of cheese powder, the relationships among variables were analyzed with Response Surface Methodology in which several independent variables such as total solid content, wheel rotation speed, and outlet temperature influenced dependent variables such as particle diameter, moisture content, bulk density, and viscosity of suspended liquid. Significance and correlation were tested according to central composite design. As a results of analyzing the correlations between independent and dependent variables, particle diameter and moisture content of cheese powder were decreased with increasing wheel rotation speed, and bulk density was decreased with increasing outlet temperature. Viscosity of suspended liquid were increased with increasing wheel rotation speed and total moisture content. In correlation among dependent variables, moisture content was proportional to bulk density, and particle diameter was inversly proportional to moisture content and bulk density.

유기물질-물-설탕의 3성분계 확산계수

강안수,김위경 명지대학교 1986 明大論文集 Vol.17 No.-

유기물질-물-설탕의 3성분계 확산 flux에 필요한 3성분계 확산계수를 격막cell 방법으로 측정하였다. 설탕수용액의 농도범위, 0∼60 wt%에서 1000ppm의 유기물질(benzaldehyde)을 용해하여 25℃의 일정한 온도에서 격막cell을 이용, 확산시킨 후 자외선 분광기 및 굴절계로 비이상성(nonideality)을 나타내는 설탕농도의 변화에 따른 benzaldehyde의 활동계수를 gas-chromatography를 이용 기상분석법으로 측정하였다. 3성분계의 확산 flux에 필요한 4개의 확산계수중 물의 주확산계수는 2성분계 확산계수를 이용하였고 benzaldehyde의 주확산계수 및 상호확산계수는 격막 cell 방법에서 유도한 식 및 본 실험에서 측정한 농도차를 이용하여 계산하였으며 나머지 benzaldehyde의 상호확산계수는 Onsager의 reciprocity관계를 이용하여 계산하였다. 실험결과 benzaldehyde의 주확산계수 및 상호작용계수는 물의 농도변화에 따라 큰 영향을 받으며 benzaldehyde의 주확산계수와 의사2성분계 확산계수는 물의 농도 차가 적을 경우 거의 비슷하다는 결론을 얻었다. 그리고 benzaldehyde의 활동도계수는 설탕의 농도가 커질수록 작아졌다. The ternary diffusion coefficients of organic component(benzaldehyde)-water-sucrose were measured with the diaphragm cell at 25℃. Solutions of sucrose ranging from 0 to 60 weight percent were prepared with the distilled water, and benzaldehyde of 1,000 ppm was then added as the dilute organic species. The difference in sucrose concentration and benzaldehyde between the solutions on either side of diaphragm cells were analyzed respectively by refractometer and ultra-violet spectrophotometer at 249.5 nm. And gas chromatographic analysis by direct head space injection was used in order to measure the activity coefficients of benzaldehyde, by which the extent of non-ideality of the system is evaluated, as a function of sucrose concentration. From the equations derived in the diaphragm cell and two independent experimental measurements, together with known binary diffusion data for aqueous sucrose solution, the three independent ternary diffusion coefficcients were determined. The fourth diffusion coefficients was then obtained from these three ternary diffusion coefficients by the use of the Onsager's reciprocity relationship. The experimental results showed that the main and cross diffusion coefficients of benzaldhyde were influenced greatly with the variation of water concentration and the main diffusion coefficients of benzaldehyde was similar to the pseudo-binary diffusion coefficients of that in the case of small concentration difference of water. And the activity coefficients of benzaldehyde decreased with increasing sucrose concentration.

이성분계 물질을 함유한 다공성 물질 건조공정의 선택성

강안수,김위경 한국화학공학회 1996 NICE Vol.14 No.1

대용량 전기이중층 커패시터의 제조

강안수 明知大學校 産業技術硏究所 2004 産業技術硏究所論文集 Vol.23 No.-

Electrodes were fabricated based on activated carbon powder BP-2O and MSP-20, conducting agent such as Super P and the mixed binders of flexible polytetrafluoroethylene (PTFE) and cross-linking dispersion agent of polyvinylpyrrolidone (PVP) to increase mechanical strength. In the electrode fabrication of unit cell, it was ascertained that electrochemical characteristics were greatly increase with 78 wt.% of BP-20 and MSP-20, 17 wt.% of Super P and 5 wt.% mixed binder (PTFE : PVP = 9 : 1). Also electric conductivity was increased and internal resistance was decreased with addition of conducting agent. We found that the 2.3V/1,300F grade EDLC would be applied to industrial safety usage such as uninterrupted power supply (UPS) because of the constant DC-ESR by IR drop regardless of discharge current.

수전해용 공유가교 SPEEK/HPA 복합막의 제조 및 물리화학적 특성

강안수,황용구,이광문,우제영,정장훈,문상봉 한국수소및신에너지학회 2009 한국수소 및 신에너지학회논문집 Vol.20 No.2

In order to improve the electrochemical, mechanical and electrocatalytic characteristics, engineering plastic of polyether ether ketone (PEEK) as polymer matrix was sulfonated (SPEEK) and the organic- inorganic blend composite membranes has been prepared by loading heteropoly acids (HPAs), including tungstophosphoric acid (TPA), molybdophosphoric acid (MoPA), and tungstosilicic acid (TSiA). And then these were covalently cross-linked (CL-SPEEK/HPA) as the electrolyte and MEA of polymer electrolyte membrane electrolysis (PEME). As a result, the optimum reaction conditions of CL-SPEEK/HPA was established and the electrochemical characteristics such as ion conductivity (σ) were in the order of magnitude: CL-SPEEK /TPA30 (σ = 0.128 S/cm-1) < /MoPA40 (σ = 0.14 S/cm-1) < /TSiA30 (σ = 0.22 S/cm-1) at 80 ℃, and mechanical characterisitics such as tensile strength: CL-SPEEK /TSiA30 ≒ /MoPA40 < /TPA30. Consequently, in regards of above characterisitics and oxidation durability, the CL-SPEEK/TPA30 exhibited a better performance in PEME than the others, but CL-SPEEK/MoPA40 showed the best electrocatalytic activity of cell voltage 1.71 V among the composite membranes. The dual effect of higher proton conductivity and electrocatalytic activity with the addition of HPAs, causes a synergy effect.

활성탄소계 섬유포 전극을 이용한 전기이중층 커패시터용 유기 전해액의 제조

강안수 대한안전경영과학회 2000 대한안전경영과학회지 Vol.2 No.2

활성탄소 분말과 탄소섬유 전극을 이용한 유기계 EDLC의 전기화학적 특성

강안수 명지대학교 산업기술연구소 2001 産業技術硏究所論文集 Vol.20 No.-

Electrodes made from activated carbon powder and carbon fiber were used with PC, DMF and GBL as a solvent and TEABF₄,TEABF₄,TEABF 6, and TEABF6 as an activated material(electrolytes). The concentrations of electrolytes were in the range of 0.2~1.2 N, the volume ratios of PC and DMF as a mixed solvent system, were 90:10, 80:20, 70:30, 60:40, 50:50, and 40:60 vol%. Electrochemical properties such as electric conductivity, internal resistance, and electric capacitance of fabricated unit cells were measured after the moisture of activated material was removed with molecular sieve. Electrochmical properties were better in mixed solvents system than in mono solvent system. The best mono solvent system was 1.0 N electrolyte of γ-butyrolactone/TEABF₄with activated carbon powder and carbon fiber electrode. and the best mixed solvent system was PC and DMF/TEABF₄above mentioned with carbon electrode showed the best electrochemical properties, such as internal resistance 0.273 Ω, and specific capacitance 20.9 F/g respectively.

액체식품의 건조시 물과 방향물질의 확산에 의한 이동

강안수 明知大學校 産業技術硏究所 1983 産業技術硏究所論文集 Vol.2 No.-

During the drying of liquid foods, the transport of water and aroma component, that is, aroma retention is governed by molecular diffusion. It was analyzed by a theoretical model based on the selective diffusion theory, and was investigated through experiment. The retention of volatile component by mixed flow type spray dryer was studied for the aqueous solutions of maltodextrine and sucrose to which benbaldehyde was added as model aroma component. The experimental results showed that the initial concentration of sugar and the temperature of hot air were important factors affecting the aroma retention in the drying process. The aroma retention was high when the initial concentration of sugar was high and when the temperature of hot air was high. Above a certain temperature of the hot air the aroma retention was decreased. The optimum temperature of the hot air was moved towards high temperature as the initial concentration of sugar was decreased.

당분중 물의 등온 흡착선

강안수 명지대학교 1982 明大論文集 Vol.13 No.-

설탕, 글루코오스, 말토오스 및 과당 등 식품중 물의 등온흡착관계가 계의 온도 40, 60 및 80℃ 그리고 공기중 물의 활동도가 0.02∼0.9 사이에서 측정되었다. 많은 식품류에서 상온에서 등온흡착실험 자료는 충분하다. 그러나 고온에서 측정시 장치 및 기술상 문제점이 많다. 본 연구에서는 20여 종의 시료를 동시에 조건을 맞춘 다음 평형상태에 도달한 후 다른 시료에 영향을 주지 않도록 꺼내어 수분함율을 측정할 수 있는 회전원판식 등온흡착 장치를 새로 고안하여 등온흡착관계를 찾아내었다. 실험결과 식품중 물의 등온흡착선의 온도 의존성을 알 수 있었다. 또 고온에서 물의 등온흡착선은 건조공정, 방향물질의 보존도, 미생물의 번식 및 식품의 포장 및 보관에 깊은 관계가 있다. 일반적인 고체식품에서 수분함율이 일정할 때 계의 온도가 높아지면 물의 활동도도 증가한다. 즉 높은 온도에서 식품의 흡습성은 줄어든다. 그러나 당분은 온도가 높아지면 시료가 주위의 습기를 빨아들여 당분이 물에 용해한다. 이 때문에 설탕, 글루코오스, 말토오스 및 과당 등의 등온흡착선은 높은 온도에서 일반적인 고체식품과 반대 경향을 나타내었다. Water vapor adsorption isotherms of four food components fructose, glucose, maltose (monohydrate) and saccharose have been measured at water activity, a_w, of 0.02 to 0.9 in the temperature range of 40℃ to 80℃ in a newly designed rotatable-disc sorption apparatus. With these data at different temperature in hand the temperature dependence of sorption isotherms can be evaluated with good approximation. The sorption isotherms of foodstuffs at higher temperatures determine the drying process, retention of volatile aroma, destruction of microorganisms as well as the packing and storage. For solid foodstuffs, an increase in temperature usually increases slightly the activity of water for a given water content. This means that the products are slightly less hygroscopic at higher temperatures. But due to the dissolution of sugar in water, the sorption isotherms of fructose, glucose, maltose and saccharose at higher temperature show important exceptions to this general rule.

噴霧粒子 分布와 噴霧乾燥에서 蒸發速度에 관한 硏究

姜安洙 명지대학교 1977 明大論文集 Vol.10 No.-

This investigation was carried out to observe the drop size distributions from the external mixing convergent type pneumatic atomizers and a computational study of the evaporation rates of sprays in co-current spray drying. Theoretical equation was derived in terms of the axial distance from the nozzle, drop size distributions, drop velocity, not air temperature. and adiabatic saturation temperature of drops. The comparisons of experimental results with the theoretical equation was brought into such conclusions that operational variables wll be decided in designing spray dryer. The thermal efficiency also discussd. The cumulative volume drop size distri-ution of spray from a pneumatic nozzle was fitted by a upper-limit function.