Freeze drying of a porous Cu-Sn alloy with unidirectionally aligned pore channels was accomplished by using a composite powder of CuO-SnO2 and camphene. Camphene slurries with CuO-SnO2 content of 3, 5 and 10 vol% were prepared by mixing with a small amount of dispersant at 50˚C. Freezing of a slurry was done at -25˚C while the growth direction of the camphene was unidirectionally controlled. Pores were generated subsequently by sublimation of the camphene during drying in air for 48 h. The green bodies were hydrogen-reduced at 650˚C and then were sintered at 650˚C and 750˚C for 1 h. XRD analysis revealed that the CuO-SnO2 powder was completely converted to Cu-Sn alloy without any reaction phases. The sintered samples showed large pores with an average size of above 100μm which were aligned parallel to the camphene growth direction. Also, the internal walls of the large pores had relatively small pores. The size of the large pores decreased with increasing CuO-SnO2 content due to the change of the degree of powder rearrangement in the slurry. The size of the small pores decreased with increase of the sintering temperature from 650˚C to 750˚C, while that of the large pores was unchanged. These results suggest that a porous alloy body with aligned large pores can be fabricated by a freeze-drying and hydrogen reduction process using oxide powders.

본 연구에서는 서양요리의 가장 기본이 되는 소스 중에 하 나인 베샤멜 소스에 우리나라 봄철에 손쉽게 얻을 수 있고, 다양한 기능성과 향리활성 물질을 가지고 있는 쑥을 동결건 조하여 소스에 첨가하여 최적의 첨가비율과 레시피를 알아 보고자 본 연구를 실시하였다. 시료로서 쑥을 밀가루 대비로 5, 10, 15, 20%를 첨가한 후 베샤멜 소스를 제조한 뒤, 기계적 검사(수분 함량, pH, 색도, 점도, 환원당, 항산화성)와 미생물 검사 및 관능검사를 실시하였고, 결과는 다음과 같이 요약되 었다. 동결건조한 쑥의 첨가량을 달리하여 제조한 베샤멜 소 스의 수분, pH, 색도를 측정한 결과는 수분은 대조군이 83.56% 로 가장 높게 나타났고, pH측정 결과는 쑥을 20% 첨가한 것 이 6.51로 가장 낮았다. 색도 중 명도와 적색도 모두 시료의 첨가량이 증가할수록 유의적(p>0.001)으로 낮아졌다. 황색도 b값은 쑥 20%를 첨가한 것이 35.82로 가장 높게 나타났다. 점 도는 대조군이 64.45 cp로 가장 낮았으며, 환원당은 대조군이 416.66 ㎎/㎖로 가장 낮았다. 총 균수의 변화를 측정한 결과는 저장 3일이 될 때까지 미생물이 검출되지 않았다. 저장 5일에 0%를 첨가한 대조군이 2.5×103 CFU/㎖이었고, 10% 첨가군까 지 1.6×102 CFU/㎖ 미생물이 검출되었으며, 15%, 20% 첨가군 에서는 검출이 되지 않았다. 저장 7일에는 모든 첨가군에서 미생물이 검출이 되었으며, 20% 첨가군은 1.1×103 CFU/㎖로 미생물이 가장 적게 검출되었다. 10, 15일에서도 쑥 첨가량이 증가할수록 미생물 총 균수의 검출이 적게 나타났다. 쑥을 첨 가한 베샤멜 소스의 DPPH 유리기 소거능 결과는 쑥의 첨가 량이 많아질수록 DPPH 유리기 소거능이 증가하였다. 관능검 사 부분은 색, 향, 맛 등과 전반적인 기호도 면에서 10% 쑥을 첨가한 베샤멜 소스가 가장 우수한 것으로 나타났다. 이에 따 라 베샤멜 소스 제조 시에 동결건조한 쑥을 첨가함에 따라 저 장성 및 항산화성 향상에 도움이 되었으며 관능적으로 10% 첨가군에서 대조군보다 높은 점수를 받은 점으로 보아, 앞으 로 소스에 부재료의 첨가제로서의 이용 가능성을 엿볼 수 있 었다. 또한 서양의 향신료의 대체제로서의 활용과 쑥의 소비 촉진의 가능성이 높다고 사료된다.

This study assessed the quality characteristics of Yanggaeng prepared with different ratios of Citrus mandarin powder: 0, 2, 4, and 6%. The moisture content was lowest in the controls, while there were no significant differences among the groups supplemented with Citrus mandarin powder. The pH significantly decreased as the amount of Citrus mandarin powder increased. The lightness (L), redness (a), and yellowness (b) were lower in control groups compared to Citrus mandarin powder groups. Texture profile analysis showed that the hardness of the Citrus mandarin powder groups were lower than the control (which was the highest). The total polyphenol and flavonoid content and DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity increased as the amount of Citrus mandarin powder increased. The result of a sensory evaluation test revealed no significant differences between the controls and groups with 2% Citrus mandarin powder added in color, smell, taste, texture, and overall acceptability.

The results of testing general components, physical property and physical function after having made steamed rice cake by adding eggplant, which caters to consumers’ tastes are as follows. It showed that when eggplant powder content increased, the moisture content of steamed rice cake with eggplant was decreased. It also showed that the lightness value (L) of steamed rice cake with eggplant powder was the highest as 82.75 in the control group. When eggplant powder content increased, the redness (a) and yellowness (b) were increased. From the results of having measured the antioxidant potential over the steamed rice cake with freezing-drying eggplant powder by DPPH radical elimination, we figured out that it was the lowest as 48.30% in the control group. As more eggplant powder was added, its elimination increased accordingly. As per hardness of steamed rice cake with eggplant, the added group with 7% was revealed as the highest at 0.757. It showed that adhesiveness was the lowest as 30.233 in the control group, and springiness and cohesiveness were on the rise as freezing-drying eggplant powder was increased. Furthermore, softness and chewiness were shown to be high in the added group with eggplant powder of 3, 5%. The evaluation over the overall preference was the highest in 5% added group. Judging from this, adding 3~5% eggplant powder against non-glutinous rice powder is considered an optimal quantity in making steamed rice cake with eggplant.

Freeze drying for porous Mo was accomplished by using MoO3 powder as the source and camphor-naph- thalene eutectic system as the sublimable material. Eutectic composition of camphor-naphthalene slurries with the initial MoO3 content of 5 vol%, prepared by milling at 55o C with a small amount of oligomeric dispersant, was frozen at -25o C. The addition of dispersant showed improvement of dispersion stability in slurries. Pores were generated subse- quently by sublimation of the camphor-naphthalene during drying in air for 48 h. To convert the MoO3 to metallic Mo, the green body was hydrogen-reduced at 750o C, and sintered at 1100o C for 2 h. The sintered samples, frozen by heated Teflon cylinder, showed large pores with the size of about 40 µm which were aligned parallel to the sublimable vehicles growth direction. The formation of unidirectionally aligned pores is explained by the rejection and accumulation of solid particles in the serrated solid-liquid interface.

Porous Ti-systems with unidirectionally aligned channels were synthesized by freeze-drying and a heat treatment process. TiH2 powder and camphene were used as the source materials of Ti and sublimable vehicles, respectively. Camphene slurries with TiH2 content of 10 and 15 vol% were prepared by milling at 50˚C with a small amount of oligomeric polyester dispersant. Freezing of the slurry was done in a Teflon cylinder attached to a copper bottom plate cooled at -25˚C while unidirectionally controlling the growth direction of the camphene. Pores were generated subsequently by sublimation of the camphene during drying in air for 48 h. The green body was heat-treated at 1100˚C for 1 h in a nitrogen and air atmosphere. XRD analysis revealed that the samples composed of TiN and TiO2 phase were dependent on the heat-treatment atmosphere. The sintered samples showed large pores of about 120 mm which were aligned parallel to the camphene growth direction. The internal wall of the large pores had relatively small pores with a dendritic structure due to the growth of camphene dendrite depending on the degree of nucleation and powder rearrangement in the slurry. These results suggest that a porous body with an appropriate microstructure can be successfully fabricated by freeze-drying and a controlled sintering process of a camphene/TiH2 slurry.

This study was conducted to examine the applicability of muffins and the optimal ratio of batter mixture by adding mugwort with various functions and physiological active substances. In result of examining the quality characteristics of muffins after adding frozen-dried mugwort powder by 0%, 1%, 3%, 5%, or 7%, the moisture retaining capacity of muffin batter was lowest with MPM0, the control group, and the deposition was highest at 17.94 ㎖ with MPM0. The pH value of muffin batter was highest at 8.62 with MPM0 and moisture decreased significantly (p<0.001) when more mugwort powder was added to the sample. The brightness increased significantly (p<0.001) when the amount of frozen-dried mugwort powder decreased and redness and yellowness decreased when the addition of mugwort powder increased. The height and volume of mugwort muffins were lowest at 4.75 ㎝ and 135.69 ㎖ with MPM7 with the greatest value of frozen-dried mugwort powder. The loss at baking of mugwort muffins was lowest at 2.27% with MPM7. The hardness of mugwort muffins was highest with MPM7 with the highest mugwort powder content. Coagulation and resilience was highest at 0.64 with the MPM0 control group and the chewiness increased significantly (p<0.001) with greater amount of frozen-dried mugwort powder. The appearance of mugwort muffins was highest at 6.1 with MPM5 and the most preferable color and flavors were found with MPM3. Tenderness was highest with the MPM0 control group. Overall preferability was highest with MPM3 with 3% frozen-dried mugwort powder. When adding frozen-dried mugwort powder to muffins, the 3% and control groups mostly showed the highest values, whereas the 5% group and higher groups showed lower values.

In order to fabricate the porous Mo with controlled pore characteristics, unique processing by using powder as the source and camphene as the sublimable material is introduced. Camphene-based 15 vol% slurries, prepared by milling at with a small amount of dispersant, were frozen at . Pores were generated subsequently by sublimation of the camphene during drying in air for 48 h. The green body was hydrogen-reduced at , and sintered at for 1 h. After heat treatment in hydrogen atmosphere, powders were completely converted to metallic W without any reaction phases. The sintered samples showed large pores with the size of about which were aligned parallel to the camphene growth direction. Also, the internal wall of large pores and near bottom part of specimen had relatively small pores due to the difference in the camphene growth rate during freezing process. The size of small pores was decreased with increase in sintering temperature, while that of large pores was unchanged. The results are strongly suggested that the porous metal with required pore characteristics can be successfully fabricated by freeze-drying process using metal oxide powders.

Dependence of the freeze-drying process condition on microstructure of porous W and pore formation mechanism were studied. Camphene slurries with contents of 10 vol% were prepared by milling at with a small amount of dispersant. Freezing of a slurry was done in Teflon cylinder attached to a copper bottom plate cooled at . Pores were generated subsequently by sublimation of the camphene during drying in air for 48 h. The green body was hydrogen-reduced at for 30 min, and sintered in the furnace at for 1 h. After heat treatment in hydrogen atmosphere, powders were completely converted to metallic W without any reaction phases. The sintered samples showed large pores with the size of about which were aligned parallel to the camphene growth direction. Also, the internal wall of large pores and near bottom part of specimen had relatively small pores with dendritic structure due to the growth of camphene dendrite depending on the degree of nucleation and powder rearrangement in the slurry.

The evaluated physicochemical and sensory properties of freeze-dried Shingo pears(Pyus pyritolia Niitaka), cultivated at Cheonan city, prepared using different sugar concentration of blanching solution we evaluated. Sliced Shingo pears(5 ㎜ and 7 ㎜ thickness) were blanched in sugar solution(0, 3, 5, 7, 10%) and freeze-dried to make dried fruits snack. The firmness of the pear snack sliced in 7 ㎜ portions was greater than the pear snacks sliced in 5mm pieces. However in sensory evaluation, pear snacks sliced in 5 ㎜ portions showed higher scores. pH and titratable acidity showed no significant difference in the blanching process. Concentration of total phenollic compound in fresh pear was 3.7 ㎎% but freeze-dried pear snacks showed higher values at 15 ㎎%. Sensory evaluation tests showed that the scores for texture decreased as the thickness of the snack and sugar concentration of blanching solution increased; however the score increased(p<0.05). Color intensity and overall acceptability scores were highest in pear snacks sliced in 7 ㎜ pieces and blanched with 7% sugar solution.

Roll milled- and nano-powders were prepared from the freeze dried fruiting bodies of Hericium erinaceum and their hydration properties such as water solubility index, swelling capacity, water holding capacity, and water sorption isotherm were compared. Water content in freeze dried Nano-powder of Hericium erinaceum fruiting body was 8.17%. Nano-powder has higher water solubility index compared to roll mill powder by 58.41% and 39.06%, respectively. In the same way, swelling capacity of nano-powder was 10.21ml/g where as roll mill powder has only 4.42ml/g. In contrast, water holding capacity of nano-powder (3.87g/g) is lower than that of roll mill powder (6.81g/g). Water sorption isotherm of these powders was compared and the result shows no big difference at low relative humidity (below75%). However, a high relative humidity above 75%, these two kinds of powder showed comparable difference. At 84.34% relative humidity, roll mill powder has 30.41% of moisture content compared with 47.64% of nano-powder, and at the relative humidity of 97.3%, the moisture content of roll mill and nano-powder are 37.64% and 91.06% respectively.

Porous W with controlled pore characteristics was fabricated by a freeze-drying process. WO3 powder and camphene were used as the source materials of W and sublimable vehicles, respectively. Camphene slurries with WO3 contents of 10 and 15 vol% were prepared by milling at 50˚C with a small amount of oligomeric polyester dispersant. Freezing of a slurry was done in a Teflon cylinder attached to a copper bottom plate cooled at -25˚C while the growth direction of the camphene was unidirectionally controlled. Pores were generated subsequently by sublimation of the camphene during drying in air for 48 h. The green body was hydrogen-reduced at 800˚C for 30 min and sintered in a furnace at 900˚C for 1 h under a hydrogen atmosphere. Microstructural observation revealed that all of the sintered samples were composed of only W phase and showed large pores which were aligned parallel to the camphene growth direction. The porosity and pore size increased with increasing camphene content. The difference in the pore characteristics depending on the slurry concentration may be explained by the degree of powder rearrangement in the slurry. The results strongly suggest that a porous metal with the required pore characteristics can be successfully fabricated by a freeze-drying process using metal oxide powders.

In order to fabricate the porous metal with controlled pore characteristics, unique processing by using metal oxide powder as the source and camphene as the sublimable material is introduced. CuO powder was selected as the source for the formation of Cu metal via hydrogen reduction. Camphene-based CuO slurry, prepared by milling at with a small amount of dispersant, was frozen at . Pores were generated subsequently by sublimation of the camphene. The green body was hydrogen-reduced at for 30 min, and sintered at for 1 h. Microstructural analysis revealed that the sintered Cu showed aligned large pore channels parallel to the camphene growth direction, and fine pores are formed around the large pore. Also, it showed that the pore size was controllable by the slurry concentration.

노상토의 동상 가능성이 없는 경우 동상방지층을 생략한다. 이러한 조건에서 노상토의 동결 융해가 발생하면, 동상이 없는 상태에서 탄성계수 변화를 수반하고, 포장설계에서 이를 합당하게 고려해야 한다. 동결 융해 과정의 연속적인 탄성계수 변화를 효과적으로 규명하고자 비파괴시험인 충격공진시험(IR, Impact Resonance)을 도입하였다. 동결 융해 과정에서 수분의 공급이 차단된 폐쇄형 동결조건에서 노상토의 탄성계수는 동결 융해 반복횟수에 무관하게 일정한 값으로 나타났다. 또한 시험에 적용한 모든 함수비 및 다짐도 조건에서 동결전의 탄성계수와 동결 융해 후의 탄성계수는 변화가 거의 없이 일정한 값으로 나타났다. 즉 폐쇄형 동결 융해 조건에서는 노상토의 융해 강성도 감소(thaw-weakening)가 발생하지 않았다. 동결시 탄성계수는 다짐도 및 함수비에 따라서 변화하였으나, 포장설계 관점에서는 무시 가능한 수준으로 나타났다.

The purpose of this study was to evaluate the biological characteristic of deproteinized freeze dried bovine bone(DFDBB) through grafting to maxillary sinus as following time lapsed. Nine patients who were needed of sinus elevation procedure because of severe resorption of maxillary edentulous alveolar bone were selected. patients were divided into three group. Firstly sinus lifting procedure was performed and then the implantation procedure was performed after 6 months in first group, 12 months in second group and 18 months in third group and simutaneously tissues of sinus were obtained by trephine. 18 sections are made from every obtained tissue. 9 sections were stained by Masson's trichrome method and were taken a photo at 100 times of magnification. Relative area of newly formed bone were obtained by IPTK(image processing tool kit) version 5.0 program and mean values and standard deviations were produced from obtained data by using SPSS version 17 program and significance tests were conducted by ANOVA method. This study revealed that DFDBB stimulated new bone formation in maxillary sinus and did not have osteoinductive capacity but osteoconductive capacity, and DFDBB was exceedingly slowly resorbed.

콘크리트의 박리(scaling)는 수분의 존재하에 동결융해 싸이클에 따른 콘크리트의 점진적인 표면열화이다. 특히, 이것은 제설제에 염화물의 존재가 콘크리트 표면박리(스켈링)와 더불어 심한 경우, 굵은골재의 노출 및 탈리로 이어질 수 있다. 본 연구에서는 콘크리트의 스켈링에 대한 저염화물계 제설제(low chloride deicier, LCD)와 염화칼슘 및 염화나트륨 제설제의 상대적인 영향을 ASTM C672에 준하여 실시하였다. 시험 제설제의 농도는 1, 4, 10% 이고, 수돗물은 기준으로 사용하였다. 박리량은 중량으로 평가하였다. 연구결과 4% 농도를 적용하였을 때, 동결융해 56 싸이클 후 콘크리트의 박리는 수돗물에 비해 LCD 용액에서 약 9배, 염화칼슘 용액에서 약 18배, 염화나트륨 용액에서 약 33배 정도 크게 발생하였다. 용액의 농도에 따라서는 고농도인 10%에 비해 4% 농도에서 표면 박리가 가장 현저하게 발생하였는데, 이는 스켈링 발생이 염농도가 3~4%일 때 가장 현저해진다는 기존의 연구결과와 일치함을 알 수 있었다(일본콘크리트공학회, 1999). 또한 콘크리트가 경화된 후, 현장에서 염화나트륨 및 저염화물계 제설제(LCD, 염소이온 중량비 50%)가 살포되고 동결융해 싸이클에 노출된 경우, 제설제에 노출되지 않은 경우의 콘크리트 동해열화에 대해, 콘크리트의 공기량에 따른 영향을 실험적으로 연구하였다. 연구 결과 동결융해 싸이클에 따른 콘크리트 시편은 제설제에 노출되지 않은 것 보다 염화물 제설제 노출에서 스켈링이 더 심한 것으로 나타났고, 염화물 제설제에 노출된 시편이 노출되지 않은 시편 보다 중량 손실이 2배나 되었다. 콘크리트 시편의 상대 동탄성계수는 염화물 제설제에 노출되지 않은 것과 비교하여 염화물 제설제에 노출된 것에서 더 빠르게 감소하였다. 또한 염화나트륨 제설제에 노출된 콘크리트 시편의 상대 동탄성계수는 저염화물계 제설제에 노출된 것 보다 더 빠르게 감소하였다. AE 콘크리트는 염화물과 동결융해 싸이클에 노출되었을 때, Non-AE 콘크리트 보다 성능저하가 크게 지연되었다.

Aloe gel의 동결건조에 농축도가 서로 다른 액상 시료를 사용하였을 때 건조분말의 기능성 변화를 비교분석하였다. Aloe의 많은 기능성 중에서 유효 다당류의 농도, 기능성 작용기에 대한 FT-IR 특성, Jack bean urease 저해 효과, FAC(fat adsorption capacity)를 대상으로 하였다. 농축도가 높은 경우에 유효 다당류의 농도, urease 저해 효과, FAC 모두 상대적으로 크게 나타났다. FT-IR의 분석에서는 농축도가 높은 경우에 glucomannan의 acetyl 기에 대한 spectrum 영역인 1600-1550 cm-1와 1450-1400 cm-1에서 흡광도가 크게 관찰되었다. 결과적으로 Aloe gel의 동결건조 시 전처리과정인 농축 공정에서는 농축도가 높을수록 유효 다당류의 양과 acetyl기 함량의 수준이 크며, 간접적으로 urease 저해 효과에 따른 Helicobacter pylori의 억제 및 FAC의 증가 효과를 보였다.