• 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.

• Journal of the Korean Ceramic Society
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• v.32 no.5
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• pp.549-558
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• 1995

Mn-Zn ferrite granules were prepared by spray drying of the slurry containing different kinds and concentration of binders at various spray drying temperatures and atomizing pressures. The characteristics of the spraydried granules were analyzed according to the processing variables of spray drying and the slurries containing different solid loading and kinds and concentration of binders. Typical shape of the spray dried granules was spherical. The granules spray dried at 15$0^{\circ}C$ were more spherical and containing lower hollow percentage than any other granules prepared at higher temperature. The granules prepared at higher atomizing pressures were more spherical and become smaller in size. The granules prepared using slurry containing higher solid loading were larger in size and less defective in shape. As increasing the concentration of binder the number of donut-shaped granules was increased and the size distribution become broader. The granules prepared using the slurry containing PVA 205 were more spherical than those containing PVA 217 and PVA 117. As the amount of granules which were donut-shaped or dimpled increased the compaction response were less effective. The hollows were not fractured completely even at hight pressures and remained after sintering.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.8
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• pp.882-887
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• 2004

The new magnetic porcelain materials have been studied by mixing magnetic St-ferrite powders with traditional porcelain materials before forming process. For the maintenance of magnetic characteristics after glaze firing process, the Sr-ferrite grains with the size of 1∼2 ${\mu}{\textrm}{m}$ were agglomerated as the isotropic granules with the size of 0.5∼2 mm. The high characteristics of magnetic porcelain materials were achieved at the following conditions; isotropic Sr-ferrite granules of 30 wt%, granule size of 1.4∼2 mm, and glaze firing temperature of $1250^{\circ}C$ in air The magnetic porcelain materials indicated the high magnetic properties, such as the remanent flux density of 240 G, the intrinsic coercivity of 3910 Oe, and the surface flux density of 178 G. The extraction properties of the magnetic tea cups were high compared to that of the traditional tea cups.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.256-257
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• 2006

3D printing of NiTi alloys has been successfully achieved. A novel printing process has been developed and used, which consists in selective deposition of a solvent on a granule bed. The granules are composed of metal powders and thermoplastic binder, which are mixed and sieved by conventional methods. A sound green strength is obtained after solvent evaporation. Sintered parts exhibit good density, proper phase composition and shape memory behaviour.

• Journal of Ceramic Processing Research
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• v.13 no.spc1
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• pp.145-148
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• 2012

Spherical silica aerogel powders were fabricated via an emulsion polymerization method from a water glass. A water-in-oil emulsion, in which droplets of a silicic acid solution are emulsified with span 80 (surfactant) in n-hexane, was produced by a high power homogenizer. After gelation, the surface of the spherical silica hydrogels was modified using a TMCS (trimethylchlorosilane)/n-hexane solution followed by solvent exchange from water to n-hexane. Hydrophobic silica wet gel droplets were dried at 80 ℃ under ambient pressure. A perfect spherical silica aerogel powder between1 to 12 ㎛ in diameter was obtained and its size can be controlled by mixing speed. The tapping density, pore volume, and BET surface area of the silica aerogel powder were approximately 0.08 g·cm-3, 3.5 ㎤·g-1 and 742 ㎡·g-1, respectively.

• Journal of the Korean Ceramic Society
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• v.54 no.2
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• pp.108-113
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• 2017

The use of aluminum-based coagulants in water pretreatment is being carefully considered because aluminum exposure is a risk factor for the onset of Alzheimer's disease. Lightly burned-dolomite kiln dust (LB-DKD) was evaluated as an alternative coagulant because it contains high levels of the healthful minerals calcium and magnesium. An organic pore forming agent (OPFA) was incorporated to prepare porous granules after OPFA removal through a thermal decomposition process. A spray drying method was used to produce uniform and reproducible spherical granules with low density, since fine dolomite particles have irregular agglomeration behavior in the hydration reaction. The use of fine dolomite powder and different porosity granules led to a visible color change in raw algae (RA) containing water, from dark green to transparent colorlessness. Also, dolomite powders and granules exhibited a mean removal efficiency of 48.3% in total nitrogen (T-N), a gradual increase in the removal efficiency of total phosphorus (T-P) as granule porosity increased. We demonstrate that porous dolomite granules can improve the settling time and water quality in summer seasons for the emergent treatment of excessive algal blooms in eutrophic water.

• Journal of the Korean Ceramic Society
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• v.45 no.10
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• pp.618-624
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• 2008

Various calcium phosphate bioceramics are distinguished by their excellent biocompatibility and osteoconductivity. Especially, the exceptional biodegradability of $\beta$-TCP makes it a bone graft substitute of choice in many clinical applications. The activation of osteoclasts, differentiated from macrophage precursor cells, trigger a cell-mediated resorption mechanism that renders $\beta$-TCP biodegradable. Based on this evidence, we studied the biodegradation process of granular-type $\beta$-TCP bone graft substitute through in vitro and in vivo studies. Raw 264.7 cells treated with RANKL and M-CSF differentiated into osteoclasts with macrophage-like properties, as observed with TRAP stain. These osteoclasts were cultured with $\beta$-TCP nano powders synthesized by microwave-assisted process. We confirmed the phagocytosis of osteoclasts by observing $\beta$-TCP particles in their phagosomes via electron microscopy. No damage to the osteoclasts during phagocytosis was observed, nor did the $\beta$-TCP powders show any sign of cytotoxicity. We also observed the histological changes in subcutaneous tissues of rats implanted with granule-type $\beta$-TCP synthesized by fibrous monolithic process. The $\beta$-TCP bone graft substitute was well surrounded with fibrous tissue, and 4 months after implantation, 60% of its mass had been biodegraded. Also, histological findings via H&E stain showed a higher level of infiltration of lymphocytes as well as macrophages around the granule-type $\beta$-TCP. From the results, we have concluded that macrophages play an important role in the biodegradation process of $\beta$-TCP bone graft substitutes.

• 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.

• Applied Biological Chemistry
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• v.47 no.3
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• pp.325-331
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• 2004

In order to study the effect of formulation type on the burning characteristics of smoke generator, fenarimol smoke generators containing the powdered rice chaff as a combustible carrier were prepared by molding the kneaded mixtures into various shapes. Smoke generators containing wood flour as a combustible carrier were also prepared and compared with smoke generators containing rice chaff. All the fenarimol smoke generators moulded into powders, granules, and rods continuously burned out when the sodium chlorate content exceeded 11%. Regardless of their types, the highest smoking rate of fenarimol was observed with more than 13% of sodium chlorate. The smoking rate of active ingredient followed with the increasing order of powder (64.5%) < granule (78.4%) < rod (90.9%). The smoke rod was robust, easy to ignite, and showed the highest smoking rate among the tested formulations. When the mixture of wood flour and anti-flame agent was used as a combustible carrier, the burning rate was so slow that wood flour formulation seemed to be more suitable to a slow-burning fumigant rather than smoke generator.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.4
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• pp.537-543
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• 2014

Three different granule powders of Citrus Hallabong were prepared with different ratios of fresh juice and citric acid (J10C3=10.0:3.08, J08C4=8.75:4.33, J07C5=7.5:5.58) at fixed quantities of juice powder (70%), pressed cake powder (10%), and additives (6.92%), and their physicochemical properties were measured and compared with targeted commercial product (CP). The moisture content of Hallabong granules (HG) was 5.08~5.44% (w/w), which was two times higher than that of CP. Titratable acidities increased with higher citric acid content and were 1.7~2.3 times lower in HG compared to that of CP. Soluble solids of HG increased with higher citrus juice content ($90{\sim}98^{\circ}Brix$) and were slightly lower than that of CP. Vitamin C contents of HG increased with higher citrus juice content and were 5.8~7.6 times lower than that of CP. In terms of color difference, L and b values of HG were higher while a value was lower than those of CP. Bulk and compaction densities of HG were 0.541~0.660 g/mL and 0.561~0.689 g/mL, respectively and were similar to those of CP. Water solubility and swelling capacity were 66.6~72.0% and 3.84~6.40 g/g, respectively, and were similar to those of CP. Hygroscopicity of HG after an hour of elapsed time was 1.6~1.8 times higher than that of CP. Sensory evaluation test showed that color, sweetness, and overall acceptance of HG were not significantly different from those of CP, whereas flavor and bitterness of HG were lower than those of CP. In conclusion, convenient food granules could be made with Citrus Hallabong juice and pressed cake, which is similar to the commercial product.