• 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.

• Nuclear Engineering and Technology
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• v.51 no.1
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• pp.198-206
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• 2019

A new methodology to analyze the nuclear material accountability for pyroprocessing system is developed. The $Pu-to-^{244}Cm$ ratio quantification is one of the methods for Pu accountancy in pyroprocessing. However, an uncertainty in the $Pu-to-^{244}Cm$ ratio due to the non-uniform composition in used fuel assemblies can affect the accountancy of Pu. A random variable, LOPu, is developed to analyze the probability of detection for Pu diversion of hypothetical scenarios at a pyroprocessing facility considering the uncertainty in $Pu-to-^{244}Cm$ ratio estimation. The analysis is carried out by the hypothesis testing and the event tree method. The probability of detection for diversion of 8 kg Pu is found to be less than 95% if a large size granule consisting of small size particles gets sampled for measurements. To increase the probability of detection more than 95%, first, a new Material Balance Area (MBA) structure consisting of more number of Key Measurement Points (KMPs) is designed. This multiple KMP-measurement for the MBA shows the probability of detection for 8 kg Pu diversion is greater than 96%. Increasing the granule sample number from one to ten also shows the probability of detection is greater than 95% in the most ranges for granule and powder sizes.

• Journal of the Korea Institute of Military Science and Technology
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• v.17 no.3
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• pp.387-393
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• 2014

The combustion pressure and thrust of aft-igniter were measured to investigate the characteristics of ignition charge. Granule and pellet shape ignition charge of $BKNO_3$ and MTV(Magnesium-Teflon-Viton) were used for igniters. Ignitions with granule charges show abrupt increases of combustion pressure and thrust compared to those of pellet charge. $BKNO_3$ igniter shows higher combustion pressure than MTV igniter due to higher combstion rate. Mg particle size affects the combustion pressure of MTV igniter.

• The Korean Journal of Pesticide Science
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• v.10 no.1
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• pp.28-35
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• 2006

This study was conducted to optimize formulation factors of a self-dispersible floating granule of flucetoaulfuron that can be used at a low application volume (5 kg $ha^{-1}$). SPA and xanthan gum were selected as a binder because blending of them showed good granulation and floatation. Potassium chloride selected as a filler also showed good granulation, floatation and disintegration properties. Among wetters and dispersants, Surfynol 440 gave the best dispersibility The optimum granule size was determined to be 1.0 mm considering floating time and dispersibility. Flucetosulfuron was mixed with the blend of SPA and xanthan gum, potassium chloride, and Surfynol 440 and formulated as a floating self-dispersible granule at 1.0 mm in diameter. Indoor and outdoor field experiments showed that the floating granule of flucetosulfuron performed well, covering long range from the application spot up to 15 m in weed control. Therefore, this floating technology may be used for laborsaving herbicide formulation development and help to reduce workloads for herbicide application.

• KSBB Journal
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• v.13 no.2
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• pp.187-194
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• 1998

For mass production of polyhydroxyalkanoates (PHA), high cell density cultures of Alcaligenes eutrophus by fed-batch culture under phosphate-limitation condition has been investigated. PHA accumulation by the regulation by the regulation of initial phosphate concentration could be automatically induced, and high density cell culture above 200 g/L also could be successfully produced. The production of Poly-$\beta$-hydroxybutyrate (PHB) and dry cell weight increased with increasing the initial phosphate concentration. When the initial concentrations of phosphate were in the ranges of 1.5~4.5 g-PO$_4$/L, PHB and dry cell weight obtained were 83~266 g/L and 61~216 g/L, respectively, and PHB productivity was in the ranges of 1.35~3.10 g/L.h. When a mixture of glucose and propionic acid is used as carbon sources, poly(3-hydroxybutyrate-co-poly-3-hydroxyvalerate), P(3HB-co-3HV), could be also successfully produced under phosphate limitation condition. When the mole ratio of propionic acid to glucose in the feeding solution is 0.22, a final dry cell weight of 150 g/L and a P(3-HB-co-3HV) of 90 g/L were produced. Morphological changes and size distribution of PHB granules synthesized in A. eutrophus under phosphate-limitation condition are determined by TEM during the course of fed-batch. Mean granule diameters of PHB produced are in the range of 0.36~0.39 $\mu$m, and mean cell size was elongated from 0.54~0.59 $\mu$m$\times$ 1.3~1.5 $\mu$m to 0.83~0.89 $\mu$m $\times$2.0~2.3 $\mu$m. Phosphate concentration in media did not affect size distribution of PHB granule and cell.

• Journal of Pharmaceutical Investigation
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• v.37 no.4
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• pp.229-235
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• 2007

Multi-layered granules were prepared by a fluidized-bed coater and uniformed granules were obtained with a size range between $950{\sim}1000{\mu}m$ in diameter. The granule system was composed of three layers, i.e. seed layer with sugar sphere bead and a water-swellable polymer, middle layer with a drug, solubilizer and polymer, and the top layer of porous membrane with a polymeric binder. The aim of this work is to find out the dependence of a drug dissolution rate on the amount of a water-soluble binder and a solubilizer in the granule system. The results showed that the higher amount of hydrophilic binder in the porous membrane, gave the bigger pore size and porosity and made faster dissolution rate and also the higher amount of solubilizer in drug layer enhanced the dissolution rate of drug.

• Applied Microscopy
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• v.28 no.2
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• pp.139-158
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• 1998

The development of the superior cervical ganglion was studied by electron microscopic method in human fetuses ranging from 40 mm to 260 mm of crown-rump length (10 to 30 weeks of gestational age). At 40 mm fetus, the superior cervical ganglion was composed of clusters of undifferentiated cell, primitive neuroblast, primitive supporting cell, and unmyelinated fibers. At 70mm fetus, the neuroblasts and their processes were ensheated by the bodies or processes of satellite cells. The cytoplasm of the neuroblast contained rough endoplasmic reticulum, mitochondria, Golgi complex, Nissl bodies and dense-cored vesicles. As the neuroblasts grew and differentiated dense-cored vesicles moved away from perikaryal cytoplasm into developing processes. Synaptic contacts between the cholinergic axon and dendrites of postganglionic neuron and a few axosomatic synapses were first observed at 70 mm fetus. At 90 mm fetus the superior cervical ganglion consisted of neuroblasts, satellite cells, granule-containing cells, and unmyelinated nerve fibers. The ganglion cells increased somewhat in numbers and size by 150 mm fetus. Further differentiation resulted in the formation of young ganglion cells, whose cytoplasm was densely filled with cell organelles. During next prenatal stage up to 260 mm fetus, the cytoplasm of the ganglion cells contained except for large pigment granules, all intracytoplasmic structures which were also found in mature superior cervical ganglion. A great number of synaptic contact zones between the cholinergic preganglionic axon and the dendrites of the postganglionic neuron were observed and a few axosomatic synapses were also observed. Two morphological types of the granule-containing cells in the superior cervical ganglion were first identified at 90 mm fetus. Type I granule-containing cell occurred in solitary, whereas type II tended to appeared in clusters near the blood capillaries. Synaptic contacts were first found on the solitary granule-containing cell at 150 mm fetus. Synaptic contacts between the soma of type I granule-containing cells and preganglionic axon termials were observed. In addition, synaptic junctions between the processes of the granule- containing cells and dendrites of postganglionic neuron were also observed from 150 mm fetus onward. In conclusion, superior cervical ganglion cells and granule-containing cells arise from a common undifferentiated cell precursor of neural crest . The granule-containg cells exhibit a local modulatory feedback system in the superior cervical ganglion and nay serve as interneurons between the preganglionic and postganglionic cells.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.32 no.5
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• pp.205-211
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• 2022

The Granule Spray in Vacuum (GSV) process is a method of forming a dense nanostructured ceramic coating film by spraying ceramic granules on a substrate at room temperature in a vacuum. In the Granule Spray, the granules made by agglomerating particles with the size from submicrometer to micrometer can be sprayed into the substrate. Once the granules were squashed upon collision with the substrate, they become several dozens of nanometer-sized crystals in vacuum process. The zirconia of the monoclinic phase transform into tetragonal phase at 1150℃. At this time, its volume is changed by about 6.5 %. For this reason, it is widely held that it is difficult to acquire a compact of monoclinic zirconia sinter. In this study, the effect of particle treatment temperature and standoff distance on the substrate of zirconia granules were investigated in GSV. Also, particle treatment temperature, standoff distance, coating efficiency, and microstructure of the film were considered in forming the monoclinic zirconia coating film in GSV without any heating process. The deposited films exhibited monoclinic zirconia phase without any other detectable phase by X-ray diffractometer (XRD).

• Applied Microscopy
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• v.18 no.2
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• pp.1-20
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• 1988

The species of the slug used in the experiment is Limax flavus L. For identifying the chemical characteristics of the epidermis, granules and mucus-producing cell of this animal is examined with methylene blue-basic fuchsin double stain and PAS-alcian blue reagent. For the ultrastructural research of the epidermal free surface, the epitheial cell and the parenchymal cell are used with scanning electron microscope and transmission elec-tron microscope respectively. I . Epidermal tissue The epidermal tissue of the slug is observed being divided into the dorsal and the ventral side(toot pad) respectively. 1) Dorsal epidermal tissue The dorsal epidermis of the slug is constituted with the simple columnar epithelium and the microvilli are compacted on the epidermal free surface. Two different types of the secretory granules of the neutral and the acid mucus are observed between the epithelial cells, and the neutral mucous granules are highest electron-dense but the acid mucous granules are observed to be electron-lucent. 2) Foot epidermal tissue The Foot epidermis is formed with the taller simple columnar epithelium than the dorsal epidermis and these cells have both a large number of the microvilli and a few number of the large villi. The secretory granules of three different types, which are acid, neutral and mixed mucous granule of two different types are observed between the epithelial cells. The neutral mucous granules are highest electron dense but the acid mucous granules are observed to be electron-lucent. II . Mucous granule-producing cell and mucus-producing cells Seven different types of the granules-producing cell and the mucus-producing cells are observed between the parenchyma. 1) A-type of acid mucous granule-producing cell The electron-lucent granules are largely occupied in the cytoplasm of these cells and then the granules are surrounded by irregular membrane. These electron-lucent granules exhibit alcianophilia with PAS-alcian blue reaction, so these granules are certified to be acid mucopolysaccharide. 2) B-type of acid mucus-producing cell The nucleus and the cytoplasm of these cells are pushed by the acid mucus of the electron-lucent toward the cell membrane. This mucus has been confirmed to be the acid mucopolysaccharide with PAS-alcian blue reagent. 3) A-type of neutral mucous granule-producing cell These cells contain the electron-dense round granules with approximately $1{\mu}m$ in diameter, which exhibit strongly PAS-positive reaction. These granules are confirmed to be the neutral mucoplysaccharide. 4) B-type of neutral mucous granule-producing cell These cells contain two different types of electron dense granules and electron-lucent granules; The former exhibits to be strongly PAS-positive and the latter to have alcianophilia reaction respectively. 5) C-type of neutral mucus-producing cell These cells are similar to the shape and the size of the B-type of mucus-producing cell but these two different types of cells are stained with reversing properties to each other. The mucus of the C-type cell that electron-lucent is largely occupied in the cytoplasm that exhibits strongly PAS-positive reaction. 6) D-type of neutral mucous granule-producing cell These cells contain round granules about $1{\mu}m$ in size which are observed to be medium electron-dense granules and those granules are stained brightly red with PAS-weak positive reaction. The granules are certified to be neutral mucopolysaccharide. 7) E-type of neutral mucous granule-producing cell These cells are similar to the shape and the size of the D-type of neutral mucous granule-producing cell. These cells contain a large number of granules with about $1{\mu}m$ in diameter showing electron-lucent and then granules are seen to be PAS-weak positive reaction. III. Parenchyma The clear cell and dark cell are found in the parenchyma of the Limax flavus L. 1) Clear cell These cells are round formed and the nucleus of the cells are larger than cytoplasm. These cells which have the electron-lucent cytosol possess poorly developed organelles. 2) Dark cell These cells are found to be dark cells due to high electron-density, which exhibit strongly methylene-blue reaction from double stain of methylene blue-basic fuchsin.

• Journal of Environmental Science International
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• v.4 no.2
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• pp.201-214
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• 1995

Design approach of upflow Anaerobic Sludge Blanket(UASB) process based on the biological kinetic parameters are known to be very difficult since the characteristics of the granular slut비e depends on the type of wastewater and size distribution of the granular sludge also depends on the upflow velocity in the UASB reactors. Furthermore, industrial wastewater containing toxic substances has been treated by UASB process without the clear knowledge of toxic effects on the granular slut형e. Hence, the present research was aimed on the intensive evaluation of biological kinetic parameters of the granular sludge in UASB reactor with and without toxic substance of 2, 4-dichlorophenol in order to present the basic design measures for UASB process design. The results could be summarized as follows. The biological kinetic parameters(k and Ks) considerably varied with the granular size of the sludge. Generally, 연e k and ks values of the granular sludge increased with the particle size of the granule. The biological kinetic parameters(k and Ks) of the granular sludge obtained from batch test were not applicable to design purpose of UASB process due to substrate diffusional limitation into the granular sludge in the completely mixed UASB reactors. The toxic effects on k and Ks greatly varied with the granular sixte. And as the toxicant concentration increased, the k value decreased while the Ks value increased. Inhibition constant(hi) for k with the toxicant of 2, 4-dichlorophenol varied from 0.5 to 2.3 depending on the granular sizes while the inhibition constant(Ki) for Ks varied from 20.7 to 80.1, showing the mixed inhibition.