• 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 Crystal Growth and Crystal Technology
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• v.27 no.1
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• pp.22-27
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• 2017

$TiO_2$ films, thickness of $1{\sim}30{\mu}m$ were deposited on glass substrate at room temperature by room temperature granule spray in vacuum. The starting powder was calcinated at $600^{\circ}C$ for 4 h using $Al_2O_3$ crucible in the furnace. The particle size of the $TiO_2$, $1.5{\mu}m$ was measured by a particle size analyzer. The effect of different process parameters such as number of pass, gas flow rate and feeder voltage was studied. As the number of passes increased, the film thickness increased proportionally due to adequate kinetic energy conserved. The effect of three different flow rates (i.e. 15, 25, and 35 LPM) on deposited film was investigated. As gas flow rate increased, the film thickness increased up to 25 LPM and then decreased. Higher feeder voltage with low flow rate of 15 LPM resulted in unsufficient coating thickness due to insufficient kinetic energy. Microstructure of $TiO_2$ films was investigated by scanning electron microscope and high resolution tramission electron microscope.

• Journal of the Korean Ceramic Society
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• v.55 no.4
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• pp.337-343
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• 2018

The influence of solid loading in the slurry composition on the morphology of 3Y-TZP granules fabricated by two-fluid spray drying was investigated for solid contents varying between 30 wt% and 50 wt%. The resulting 3Y-TZP granules showed a sphere-like shape with diameters of $40-70{\mu}m$. However, a donut-like shape and a few cracks were observed on the granule surfaces fabricated using the slurry with 50 wt% solid content. The green density after cold isostatic pressing at 200 MPa was $2.1-2.2g/cm^3$, and a homogeneous fracture surface was obtained by complete destruction of granules. After sintering at $1500^{\circ}C$ for 2 h, all specimens had relative densities of 96.2 - 98.3%. With increasing solid content, the relative density decreased from 98.3% to 96.2%, but the grain size increased from $0.3{\mu}m$ to $0.6{\mu}m$. Highly sinterable zirconia granule powder could be obtained by controlling the slurry composition.

• Food Science and Preservation
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• v.11 no.2
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• pp.148-153
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• 2004

The organoleptic properties of granule tea was optimized for granulation of Polygonatum sibiricum Delar(Dunggulle) tea for exclusion of scorched smell and increase of consumption. The length of 2 mm was suitable to cutting size of Dunggulle for preparation of the roasted Dunggulle. The optimum sensory conditions for aroma of Dunggulle granule tea showing 7.85 organoleptic score were 80.61% in ratio of Dunggulle extracts to total extracts, 12.77% in content of total extracts and 37.33% in rate of glucose to total sugar. The highest score of overall palatability was 5.96 at 61.11% in rate of Dunggulle extracts to total extracts, 13.79% in content of total extracts, and 60.92% in rate of glucose to total sugar.

• Bulletin of the Korean Chemical Society
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• v.35 no.2
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• pp.605-609
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• 2014

Magnetic multi-granule nanoclusters (MGNCs) were investigated as an inexpensive means to effectively remove arsenic from aqueous environment, particularly groundwater sources consumed by humans. Various size MGNCs were examined to determine both their capacity and efficiency for arsenic adsorption for different initial arsenic concentrations. The MGNCs showed highly efficient arsenic adsorption characteristics, thereby meeting the allowable safety limit of $10{\mu}g/L$ (ppb), prescribed by the World Health Organization (WHO), and confirming that 0.4 g and 0.6 g of MGNCs were sufficient to remove 0.5 mg/L and 1.0 mg/L of arsenate ($AsO_4{^{3-}}$) from water, respectively. Adsorption isotherm models for the MGNCs were used to estimate the adsorption parameters. They showed similar parameters for both the Langmuir and Sips models, confirming that the adsorption process in this work was active at a region of low arsenic concentration. The actual efficiency of arsenate removal was then tested against 1 L of artificial arsenic-contaminated groundwater with an arsenic concentration of 0.6 mg/L in the presence of competing ions. In this case, only 1.0 g of 100 nm MGNCs was sufficient to reduce the arsenic concentrations to below the WHO permissible safety limit for drinking water, without adjusting the pH or temperature, which is highly advantageous for practical field applications.

• Korean Journal of Veterinary Research
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• v.36 no.1
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• pp.1-9
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• 1996

Functional and morphological characteristics of the exocrine pancreas in genetic model BB rat of insulin dependent diabetes medllitus(IDDM) were carried out. Wistar rat was used as control animal. Flow rate of pancreatic juice, output of amylase and protein, and plasma glucose and insulin levess were examined. Also light and ultrastructural characteristics of the exocrine pancreas were observed. Pancreatic flow rate, output of amylase and protein, and insulin level were lower;glucose level was higher comparing with those of the control Wistar rat. In Wistar rat, exocrine pancreas was typical light microscopically. Zymogen granules and cell organelles were well developed in fine structure. Cell size of the periinsular acini was larger, and number of zymogen granules were more than those of the teleinsular acini. Most acinar cells were dark cells which containe well-developed RER in their cytoplasm. On the other hand, some light cells which have the dilated RER cisterns were found. In BB rat exocrine pancreas, cell size of per-and tele-insular acini similar to that of Wistar rat. The number of light cells occupied 40-50% compairing with that of Wistar rat. Zymogen granules were lower in number than that of Wistar rat and divied into three types in morphological characteristics ; type I showing normal structure, type II showing the wide hallo and small electron dense core in center of the zymogen granule and type III not having the electron dense core in the zymogen granule. The present ratio of type I, type II and type III are less than 5%, 30-40% and more than 50%, respectively.

• Applied Chemistry for Engineering
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• v.22 no.6
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• pp.642-647
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• 2011

The fabrication characteristics of porous uranium oxide granules from $U_3O_8$ powder was investigated in terms of initial particle bed motions such as slumping and rolling, thermal treatment conditions, and rotational velocities in slumping motion using a rotary voloxidizer. With respect to the initial particle bed motion the recovery rate of granule of above 1 mm in slumping motion was higher than that in the rolling motion. Rolling motion was changed into slumping motion with high slumping frequency by formation of granules from fine particles. Recovery rate of granule significantly increased with the increas in thermal treatment temperature and time of upto 10 h. As the rotational velocity of voloxidizer in the case of the initial particle bed showing slumping motion increased, the recovery rate of granule increased from 81.5 to 88.7%. However, the rotational velocity of 2 rpm provided an effective density, crushing strength and sphericity of granules.

• YAKHAK HOEJI
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• v.18 no.4
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• pp.236-242
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• 1974

Extrusion-spheronization processing combination was used to produce spherical granules with experimental formulations which contain microcrystalline cellulose as a diluent. The produced granules were compared on the basis of the following physical properties ; (a) bulk density, (e) porosity, (f) friabillity and (g) dissolution rate. With the specific experimental formulations used in this study, the increased plate rotational speeds of Marumerizer (400-1200rpm) produced continually more spherical material and also the obtained data indicated that the particle size distribution and dissolution rate depend upon the amount of microcrystalline cellulose used. As a result, the spherical granule preparation with microcrystalline cellulose has good properties in flow rate, packing propertyu and friability and offers a suitable method of granule preparation in pharmaceutical industry.

• Korean Journal of Plant Taxonomy
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• v.42 no.1
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• pp.24-39
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• 2012

The palynological study of 31 taxa of Korean Artemisia L. was carried out to evaluate their taxonomic characteristics and to determine the relationships among the taxa. The size and shape of the pollen are not used as characteristics to classify the taxa of Korean Artemisia L., but the granule distribution ands pinule connection on the exine were useful for an interspecific classification and for reflecting the relationship between some taxa. It is considered that Artemisia pollen has evolved from a connected spinule and a nearly psilate surface into 1) a connected spinule and a granule surface, 2) a disconnected spinule and a granule surface, 3) a disconnected spinule and a dense granule surface. These pollen characteristics with external morphological characteristics, a geographical distribution and a somatic chromosome number are considered to be good characteristics for distinguishing the relationship of some taxa, such as the A. japonica group (A. hallaisanensis, A. angustissima, A. littoricola) and the A. sacrorum group (A. sacrorum var. sacrorum, A. sacrorum var. incana, A. sacrorum var. iwayomogi).

• Applied Microscopy
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• v.17 no.1
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• pp.98-114
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• 1987

Degranulation of the rat peritoneal mast cell induced by intraperitoneal injection of horseradish peroxidase(HRP) was studied using light and electron microscopes. 1. Rat peritoneal mast cells in the Tyrode's buffered salt solution injected control group did not show any particular morphological changes following the specified time course. 2. Under the light microscope, the majority of mast cells observed 10 minutes after HRP injection were nearly the same as those of the control group. However, after 30 minutes, granule densities or staining properties of certain cells began to decrease and these appearances increased gradually until 12 hours after injection, at which time small groups of granules being stained pale-red or pink with toluidine blue were easily identified in the cytoplasm of many cells, and numerous extruded granuleg were scattered around these cells. 3. In the mast cells representing the early stage of degranulation induced by HRP, the electron densities of certain granules decreased as the size enlarged, and perigranular cavities were formed by perigranular membrane expansion. As a result, a thin cytoplasmic septum was formed between the expanded perigranular membrane and the cytoplasmic membrane in the cell periphery, and fusion of the adjacent perigranular membranes was observed in the inner side of the cell. 4. In some mast cells, one or two changes in the peripheral cytoplasmic septum could be seen. One was a focal rupture of the peripheral septum and the other was the formation of a saccule containing one or more vesicles. This saccule was thought to be used for granule-extrusion site and/or material absorptive apparatus judging from the morphological characteristics. 5. As the degranulation proceeded, the granule was extruded from the cell after partial rupture of the peripheral cytoplasmic septum. This phenomenon proceeded to-ward the inner side of the cell through the fused perigranular cavities, and consequently several distinct cavities containing a few unextruded membrane-free granules were formed throughout the cytoplasm after 12 hours. As a rule, the granule-extrusion sites were relatively fewer while the cytoplasmic cavities resulting from degranulation were more numerously observed. Thus, it was thought that the granule-extrusion sites tended to be restricted in the HRP-induced degranulation.