• Journal of Chitin and Chitosan
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• v.23 no.4
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• pp.234-243
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• 2018

In this study, the physicochemical properties of freeze dried (FD) and spray dried powders (SD-MD10, SD-MD20, SD-CD10, SD-CD20) from green coffee bean extract were investigated. Yields were 91.46% for FD powder and 71.63~87.98% for SD powders, respectively. The moisture content of SD powders (1.39~1.86%) was lower than that of FD powder (3.19%). L, a and b value of SD powders were higher than of FD powder. The particle size of the FD powder ($147.67{\mu}m$) was higher than that of the SD powders ($54.23{\sim}66.07{\mu}m$). The water absorption index of the SD powders (0.51-0.59) were lower than that of the FD powder (0.72). The water solubility index of the SD powders, 77.26-90.07%, was higher than that of the FD powder (70.07%). The total phenolic and flavonoid contents of SD-CD10 were 20.67 g/100 g and 8.92 g/100 g, respectively. The chlorogenic acid content of SD-CD10 (12.04 g/100 g) was higher than other SD powders. The DPPH and superoxide radical scavenging activities of SD-CD10 at $1,000{\mu}g/mL$ were 88.02% and 86.89%, respectively. The SD-CD10 was better than other SD powders on protective effects against oxidative stress in L-132 cells (87.33%). In conclusion, we provided experimental evidence that spray-dried powder of green coffee bean extracts have potential as functional food materials.

• Journal of Powder Materials
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• v.30 no.5
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• pp.424-430
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• 2023

YAG phosphor powders were fabricated by the atmospheric plasma spraying method with the spray-dried spherical YAG precursor. The YAG precursor slurry for the spray drying process was prepared by the PVA solution chemical processing utilizing a domestic easy-sintered aluminum oxide (Al₂O₃) powder as a seed. The homogenous and viscous slurry resulted in dense granules, not hollow or porous particles. The synthesized phosphor powders demonstrated a stable YAG phase, and excellent fluorescence properties of approximately 115% compared with commercial YAG:Ce³⁺ powder. The microstructure of the phosphor powder had a perfect spherical shape and an average particle size of approx imately 30 ㎛. As a result of the PKG test of the YAG phosphor powder, the synthesized phosphor powders exhibited an outstanding luminous intensity, and a peak wavelength was observed at 531 nm.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.31 no.6
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• pp.264-269
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• 2021

In this study, amorphous aluminum silicate powder was prepared using co-precipitation method, and the influence of spray-dried aluminum silicate granular powder was analyzed and optimized by controlling the amount of aluminum silicate powder and dispersant added to the slurry. As a result, granular powder was optimally produced under the conditions of powder content of aluminum silicate slurry of 27.5 wt% or less, dispersant addition amount of 0.8 wt% or more, pH 6~9. An average particle size of granular powder showed approximately 14 ㎛ at the powder contents of 20 and 22.5 wt% of the slurry, and approximately 19 ㎛ at the powder contents of 25 and 27.5 wt% of the slurry.

• Journal of Powder Materials
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• v.5 no.1
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• pp.28-34
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• 1998

Plasma sprayed ceramic coatings are widely used in various industrial fields to improve their properties or to reduce the production cost. The ceramic powders for plasma spray coating have been mainly manufactured by spray drying or fused+crushed process. In this study, chromium oxide which has better mechanical properties than those of the other ceramic was selected and agglomerated chromium oxide powders for plasma spray coating were produced by spray drying process with a various processing condition. The large hollow powders and the harsh surfaced powders are formed at high slurry feed rate more than 163 g/min. and low binder concentration less than 2wt%, respectively. These powders cause the considerable decrease of flowability and apparent density. The powders produced by spray drying process have the spherical shape with the mean size of 45 ${\mu}m$, but these are shown lower apparent density and flowability than the powders produced by fused+crushed powders. The plasma spray coated layers by spray dried powders are shown a different microstructure with that by fused+crushed powders in porosity shape, but their properties such as density, hardness and bond strength are similar.

• Korean Journal of Food Science and Technology
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• v.38 no.1
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• pp.52-58
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• 2006

Characteristics of dough added with up to 4.0% takju powder and resultant bread were studied. Doughs added with takju power spray-dried after fermentation with starter (SDWS) and takju power spray-dried after fermentation without starter (SDOS) showed higher pH decreases than those added with takju power freeze-dried after fermentation with starter (FDWS) and takju power freeze-dried after fermentation without starter (FDOS) even after 1st fermentation. After 1st fermentation, volume of dough added with 1-4% SDWS was high, with 1% SDWS showing highest value of 23.6 mL. Volume of bread added with SDOS showed highest value. At 1-2% SDWS and SDOS addition, doughs showed highest specific volume values, which decreased at higher than 3% addition, while specific volume increased with increasing FDWS and FDOW contents. L values of SDOS- and FDOS-added doughs decreased gradually with increasing SDOS and FDOS contents compared to SDWS and FDWS addition. In loaf bread added with takju powder less than 2%, loaf bread added with spray-dried takju powder had higher appearance, color, texture, taste, and overall acceptability values compared to those added with freeze-dried takju. Although not significantly, loaf bread added with 1% SDWS showed slightly higher values in appearance, color, yeastiness, texture, taste, and overall acceptability, and showed higher flour odor acceptability than non-added loaf bread. These results indicate addition of takju powder improves flavor of bread.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.1323-1328
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• 2004

This paper shows the study on the design of the spray-freeze dryer for the production of the pulmonary inhalation powders. Powder production and handling has been an integral part of pharmaceutical processing because of the wide use of oral dosage forms. There are a few commonly used powder preparation methods including mechanical milling, precipitaion, spray drying, freeze drying, and so on. In general, methods available for preparing inhalation powders are limited due to certain inhalation powder's sensitive nature to the processing environments. This is particularly true for preparing dry powder aerosols where the aerodynamic particle size$(<5{\mu}m)$ and the size distribution are pivotal. Supercritical fluid antisolvent and spray freeze drying have recently emerged as promising techniques for producing powders for use in microcapsulation. However, the aerosol applications of these powders are yet to be explored. The purpose of this study is to test the feasibility of using spray freeze-dried pulmonary inhalation powders for aerosolization.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2004.11a
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• pp.1-6
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• 2004

This paper shows the study on the design and another applications of the spray-freeze dryer for the production of valuable material powders. Powder production and handling has been an integral part of material extracting processing and pharmaceutical processing because of the wide use of oral dosage forms. There are a few commonly used powder preparation methods including mechanical milling, precipitaion, spray drying, freeze drying, and so on. In general, methods available for preparing inhalation powders are limited due to certain inhalation powder's sensitive nature to the processing environments. This is particularly true for preparing dry powder aerosols where the aerodynamic particle size($<5{\mu}m$) and the size distribution are pivotal. Supercritical fluid antisolvent and spray freeze drying have recently emerged as promising techniques for producing powders for use in microcapsulation. However, the aerosol applications of these powders are yet to be explored. The purpose of this study is to test the feasibility of using spray freeze-dried valuable material powders for aerosolization.

• Korean Journal of Materials Research
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• v.9 no.12
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• pp.1205-1210
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• 1999

Far infrared ceramic/aluminum composite powders for thermal spray were fabricated by spray drying method and investigated the characteristics of the plasma sprayed coating layers, I.e. microstructure, phases, thermal shock resistance and spectral emissivity. The shape of the spray dried composite powder was spherical and the particle size distribution was 34~105${\mu}m $. Aluminum was distributed homogeneously in the spray dried composite powder. Spectral emissivity of the plasma sprayed coating layer ranges from 3 to 14${\mu}m $ whereas spectral emissivity of the raw ceramic powder ranges from 8 to 14${\mu}m $. And then spectral emissivity of the coatings was better than that of the raw powder but spectral emissivity was decreased with increasing aluminum content. It was found that aluminum content ranging from 20 to 30wt% was suitable for fabricating far-infrared radiator by plasma spraying method.

• Korean Journal of Food Science and Technology
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• v.42 no.3
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• pp.310-316
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• 2010

The objective of this study was to determine the optimum manufacturing conditions of whole egg powder with high foaming property sufficient for making sponge cakes. Whole eggs were either desugarized and/or adjusted pH before spray-dried at a temperature of $70^{\circ}C$. The physical properties of the cake were measured, and sensory evaluation was conducted on a 9-point scale. The pH and specific gravities of the foam and batter made from desugarized egg powder did not differ from those of the control, whereas batter made from commercial powder experienced significant loss of cake characteristics. The pH adjustment did not improve the foaming properties of the egg powders. The volume and textural properties of the cakes made from spray-dried egg did not differ from those of fresh egg. The taste and sensory characteristic scores for fresh egg, desugarized whole egg powder, and commercial powder were 5.00, 4.78, and 1.89, respectively. These results indicate that egg powders desugarized and spray-dried at $70^{\circ}C$ are sufficient for making sponge cakes with acceptable physical and sensory attributes.

• Korean Journal of Materials Research
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• v.27 no.12
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• pp.716-721
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• 2017

SiAlON-based ceramics are some of the most typical ceramic materials used as cutting tools for HRSA(Heat Resistant Super-Alloys). SiAlON can be fabricated using ceramic processing, such as mixing, granulation, compaction, and sintering. Spray drying is a widely-used method for producing a granular powder of controlled morphology and size with flowability. In this study, we report a systematic investigation aimed at optimizing spherical granule morphology by controlling spray-drying parameters such as gas flow and feed rate. Before spray drying, the viscosities of the raw material slurries were also optimized with the amount of dispersant added.