• Title/Summary/Keyword: granule size

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Preparation of Granule Powders for Thermal Spray Coating by Utilization of Pyrophyllite Minerals

  • Kim, Yong-Hyeon;Shin, Pyung-Woo;Lee, Sang-Jin
    • Journal of the Korean Ceramic Society
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    • v.53 no.5
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    • pp.557-562
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    • 2016
  • Pyrophyllite granule powders for thermal spray coating were successfully prepared through spray drying process. To produce a stable slurry, commercial pyrophyllite powder of $45{\mu}m$ in size was ball-milled for reduction of the size to $2{\sim}3{\mu}m$ and a dispersant was added to control the viscosity. Dense and spherical granules (average granule size : $59{\mu}m$) were prepared under conditions of 12,500 rpm for rotation velocity of the atomizer and 100 cps for slurry viscosity. The granules were then heat treated at $1,200^{\circ}C$ for proper handling strength and flow properties. The final granules had an apparent density of $0.725g/cm^3$ and a flow rate of 2.5 g/sec, which represent excellent properties to be used as the granule powder for thermal spray coatings.

PHYSICOCHEMICAL CHARACTERIZATION OF UASB GRANULAR SLUDGE WITH DIFFERENT SIZE DISTRIBUTIONS

  • 안영희;송영진;이유진;박성훈
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2001.04a
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    • pp.172-181
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    • 2001
  • Upflow anaerobic sludge blanket (UASB) system employs granular sludge to treat various wastewaters including landfill leachate. CH$_4$ production of the granules determines overall performance of a UASB reactor. Sludge granules are developed by self-granulation of microorganisms and dynamic balance between granule growth and decay results in coexistence of granules with different sizes in the reactor. In this study, granules taken from a laboratory-scale UASB reactor were classified into 4 groups based on their diameters and their Physicochemical characteristics we were investigated. Each group was analyzed for settling ability, specific methanogenic activity (SMA), and elemental content. Settling ability was proportional to granule diameter. suggesting effective detainment of larger granules in the reactor. When acetate or glucose was used as a substrate, all groups showed relatively slight difference in SMA. However SMA with a volatile fatty acid mixture showed significant increase with granule diameter, suggesting better establishment of syntrophic relationship in larger granules. Larger granules showed higher value of SMA upon environmental changes (i.e., PH, temperature, or toxicant concentration). Comparative analysis of elemental contents showed that content (dry weight %) of most tested elements (iron, calcium, phosphorus, zinc, nickel. and manganese) deceased with granule diameter, suggesting importance of these elements for initial granulation. Taken together, this study verified experimentally that Physicochemical Properties of granules are related to granule size distributions. Overall results of physicochemical characterization supports that larger.

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A Study on the Basic Property of Mortar as the Grading Distribution of Copper Slag Used as Fine Aggregate (잔골재로 사용한 동슬래그의 입도에 따른 모르타르의 기초적 특성 연구)

  • Lee Jong-Chan;Lee Mun-Hwan;Lee Sea-Hyun
    • Proceedings of the Korea Concrete Institute Conference
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    • 2005.05b
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    • pp.97-100
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    • 2005
  • The purpose of this study is to research the basic property of mortar as the grading distribution of copper slag used as fine aggregate and the results are as follows. The compressive strength of mortar as the size of largest diameter of copper slag granule is the highest when the largest size is in 2.5-5mm, and flow of mortar is in proportion to the size. As the largest size of copper slag particle is under 2.5mm(Type 1) the compressive strength and flow is higher as the big granules is more included than small ones. As the largest size of copper slag granule is under 5mm(Type 2) the compressive strength and flow is similar to situation of Type 1, except compressive strength is higher as the percent of the size of granule in $2.5\~5mm$ is under 35$\%$. F.M.(Fine Modulus), compressive strength and flow is relative each other except the batch with 2.5$\∼$5mm granule size of copper slag.

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Factors Affecting Gelatinization Temperature of Rice Starch (쌀 전분의 호화온도에 영향을 주는 요인들)

  • 이영은;오스만엘리자베쓰엠
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.20 no.6
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    • pp.646-652
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    • 1991
  • Factors affecting gelatinization temperature of rice starches from different varieties were investigated. Birefringence end-point temperature(BEPT), amylose content, granule size distribution and degree of crystallinity of rice starches showed the significant varietal differences at ${\alpha}\;=0.01$. Susceptibility of the granule to gelatininzation was dependent mainly on the degree of crystallinity, as indicated by the significant positive correlation between BEPT and the relative crystallinity(r=0.67, p<0.01). However, granule size distribution did not affect the GT(gelatinization temperature) range, nor did amylose electron microscopy (SEM). SEM also confirmed that there is no relationship between the size and the shape and the amylose content of the rice starch.

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Study on the Granulation Behavior of TiO2-PVA Composite Powders Prepared Via Spray Drying Technique

  • Avcioglu, Celal;Ozkal, Burak
    • Journal of the Korean Ceramic Society
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    • v.56 no.5
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    • pp.443-452
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    • 2019
  • In this study, TiO2-polyvinyl alcohol (PVA) composite granules were prepared via spray drying technique. To investigate the effects of solid content and binder/powder ratio in the slurry on the granulation behavior of TiO2 powders, the feed compositions were designed to vary over a wide range. The morphology, actual densities, and average granule size and size distribution of the TiO2-PVA composite granules were characterized by using scanning electron microscopy technique, a gas pycnometer, and an image analyzing program (Image-J), respectively. The results indicate that solid content and the amount of PVA in the feedstock slurry are the dominant factors determining the granule morphology, size, and size distribution of TiO2-PVA composite. Moreover, it was observed that increasing the solid content and the amount of PVA in the slurry improved the granulation process and reduced the granule defects. For the preparation of spherical TiO2-PVA composite granules with the minimum amount of non-granulated powders, the optimized composition of the feedstock slurry was found to be 35 wt.% solid and 3 wt.% PVA.

Effect of Granule Size on Physical Characteristics of Ginseng Tablet (과립의 크기가 인삼정제의 물리적 특성에 미치는 영향)

  • Park, Myeong-Han;Seong, Hyeon-Sun;Kim, U-Jeong
    • Journal of Ginseng Research
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    • v.4 no.1
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    • pp.96-103
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    • 1980
  • The effect of granule size of dried red ginseng extract on physical characteristics on tablet such as hardness, color, yield and disintegration time was studied. A moisture proofing agent was found to be necessary to form granules without serious absorption of moisture. The result showed that decrease in particle size resulted increase of values in weight, hardness and disintegration time. The granule size of 60∼80 mesh was found to be optimum for proper color uniformity and other physical characteristics of tables.

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Ultrastructural Study on the Development of the Small Granule-Containing Cells in Superior Cervical Ganglion of Human Fetus (인태아 상경신경절내 소형의 과립함유세포에 관한 전자현미경적 연구)

  • Yoon, Jae-Rhyong;Min, Young-Don;Nam, Kwang-Il
    • Applied Microscopy
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    • v.26 no.3
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    • pp.349-367
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    • 1996
  • The development of small granule-containing cell in the superior cervical ganglion was studied by electron microscopic method in human fetuses ranging from 40 mm to 260 mm crown rump length (10 to 30 weeks of gestational age). At 40 mm fetus, the superior cervical ganglion was composed of clusters of undifferentiated cells, primitive neuroblasts, and unmyelinated nerve fibers together with blood vessels. At 90 mm fetus, the superior cervical ganglion consisted of neuroblasts, satellite cell, small granule-containing cells, and unmyelinated nerve fibers. Two morphological types of the small granule-containing cells in the superior cervical ganglion were first indentified at 90 mm fetus, but were rare. Type I granule-containing cell occurred in solitary and had long processes, whereas type II cells tend to appeared in clusters near the blood capillaries. The granule-containing cells were characterized by the presence of dense-cored vesicles ranging from $150{\sim}300nm$ in diameter in both the cell bodies and processes. Other organelles included abundant mitochondria, rough endoplasmic reticulum, neurotubules, and widely distributed ribosomes. The granule-containing cells had long processes similar to those found in principal ganglionic cells. They could be identified by their content in dense-cored vesicles. The small granule-containing cells increased somewhat in size and number with increase of fetal age. Synaptic contacts were first found on the solitary granule-containing cell at 150 mm fetus. Synaptic contacts between the soma and processes of type I granule-containing cells and preganglionic axon terminals were observed. In addition, synaptic junctions between the processes of granule-containing cells and presumed dendrite of postganglionic neuron were also observed from 150 mm onward. On the basis of these features type I granule-containing cells could be considered as interneurons. The clusters of type II granule-containing cells were located in the interstitial or subcapsular portions of the ganglion, and had short processes which ended in close relation to fenestrated capillaries. Therefore it may be infer that clusters of type II granule-containing cells have an endocrine function.

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Preparation and Release Characterization of Osmotic Granule Nifedipine Delivery System (니페디핀 삼투성 과립 시스템의 제조와 약물 방출 특성)

  • Jeong, Sung-Chan;Cho, Young-Ho;Lee, Soo-Young;Lee, Bong;Kim, Moon-Suk;Kang, Gil-Son;Lee, Hai-Bang
    • Journal of Pharmaceutical Investigation
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    • v.36 no.1
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    • pp.11-17
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    • 2006
  • The objective of this study was to confirm the effect of the type of dissolution media and paddle speed on nifedipine (ND) release profile from osmotic granule and the storage stability. Osmotic granule was manufactured by fluidized bed coating method. At each coating step, morphology of osmotic granule was differed. The size of osmotic granule was $750\;{\mu}m$ at 3 wt% membrane thickness. ND release was changed in diverse dissolution media, paddle speed. ND release is governed by not only osmotic pressure but diffusion from osmotic granule. ND release from osmotic granule decreased as storage period increased. These may be caused by liquid excipient which has low molecular weight. Storage stability of osmotic granule could be improved by removing liquid excipient from semipermeable membrane.

The study of handiwork techniques of ancient granule (고대 누금 세공기법 제작기술 연구)

  • Moon, Whan-Suk;Cho, Nam-Chul;Hong, Jong-Ouk
    • 보존과학연구
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    • s.22
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    • pp.81-92
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    • 2001
  • The replica experiment of golden bell excavated from the East Three-Story Pagoda at the Gamunsa temple was carried out in order to know the handiwork technique of ancient granule. The size of 0.3mm granule was attached to the golden bell which was 3.4mm bell body by soldering. When we tried to attach the granule by a modern metalwork, we could know that this technique was hard to make the replica bell. We could prove how to adhere strongly to the golden granule by tension testing. First of all, we made the soldering of the same composition as the golden bell excavated from the Gamunsa temple and then prepared specimens for testing to measure the tension strength. It showed that the broken position was not a soldering part. This result showed how the ancient granule could maintain without a break for a long time.

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Ultrastructural Study on the Parenchymal Cell of Korean Planaria (Dugesia japonica) (한국산 플라나리아(Dugesia japonica Ichikawa et Kawakatsu) 유조직의 미세구조에 관한 연구)

  • 장남섭
    • The Korean Journal of Zoology
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    • v.30 no.1
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    • pp.53-70
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    • 1987
  • The morphological study on the parenchymal cells in the adult planaria performed to observe their cytochemical and ultrastructural characteristics. The results are as follows. Nine types of cells are found in parenchyma. 1. Free parenchymal cell: These cells contain several chromatoid bodies around the nucleus. Heterochromatins are evenly dispersed in large nucleus. These cells are abundant in free ribosomes. 2. Fixed parenchymal cells: These cells have well-developed granular endoplasmic reticulum, mitochondria and Golgi complex but they contain the cytosols exhibiting electron-lucencies. 3. Rhabdite-forming cells: These cells contain the electron-dense rhabdite granules of up to about 0.3 x 0.9 $\mu$m in size. Rhabdite-forming cells have well-developed cell organelles, granular endolplasmic reticulum, mitochondria and Golgy complex. 4. A-type of basophilic granule cells: These cells contain irregularly-shaped granules exhibiting alcianophilia. These granules surrounded by a limited membrane, approximately 1.4 x 0.7 $\mu$m in size, are accumulated in the cytoplasm. 5. C-type of basophilic granule cells: These cells contain electron-dense granules of less than 0.2 $\mu$m in size, which exhibit PAS- positive reaction. This type of granule is also found in the muscle layer of parenchyma. 6. D-type of basophilic granule cells: This type of granule cell occurs only in the parenchyma around reproductive organ. The granules have cytochemical characteristics that they exhibit strongly positive reaction with PAS and weakly eosinophilic property. These electron-dense granules, which are 0.2 to 0.6 $\mu$m in length, have oval shapes. 7. E-type of basophilic granule cells: These cells are found only in the parenchyma around re productive organ. The granules contained in a small number in the cell, exhibit PAS-positive reaction and have an average size of 0. 2pm. 8. Eosinophilic granule cells: These cells contain a large number of eosinophilic granules which have relatively diverse sizes from 0.3 x 0.2 to 0.8 x 0.4 $\mu$m. Most of granules are round or irregularly-shaped and highly electrondense. These cells have an array of well-developed granular endoplasmic reticulum of which cisternae are distened. 9. Transparent granule cells contain electron-lucent granules which exhibit negative reactions with three kinds of cytochemical methods used in this experiment.

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