• Microbiology and Biotechnology Letters
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• v.17 no.4
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• pp.349-357
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• 1989

Uncooked starch can be effectively saccharified in an enzyme reaction system containing attrition-milling media. To develope the high efficiency bioattritor, an agitated bead type bioreactor was constructed, and its effectiveness was evaluated. The optimal operation condition of bioattritor was found to be 300 g glass bead/L, 200 rpm, standard type impeller for 220 g/L of uncooked corn starch. The torque under the various operational conditions were also measured. The interrelation-ship between energy consumption for agitation of attrition-milling media and enhanced extent of saccharification of uncooked starch was evaluated, Power consumption was measured to be around 1.53 watt/L under the optimal operation condition. The attrition coupled enzyme reaction system is identified to tie a very excellent energy saying process for saccharification of uncooked starch, and seems to have a bright prospect of industrial application.

• KOMUNHWA
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• no.60
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• pp.101-120
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• 2002

The floor tile on a coated green-glass was excavated from the Beobgwangsa Temple Site in the Pohang City. We analyzed using the MXRD, ICP-AES, EDXRF, TG/DTA and TIMS. As a result of microscope analysis, it was composed of quartz, feldspar and clay particl

• Applied Microscopy
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• v.35 no.3
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• pp.177-186
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• 2005

The foregut epithelium of the last instar larva in the scarab beetle, Allomyrina dichotoma was observed with electron microscopes. The foregut epithelium of the scarab beetle larva is composed of a single-layered squamous absorptive cell. The luminal surface of the epithelium is covered with cuticular intima. The free surface of the squamous cell has a irregular array of microvilli 'brush border', while cell membrans close to the basal lamina are infolded and a lot of mitochondria are concentrated in those processes. The cytoplasm in the epithelial cells is well developed nucleus, mitochondria. And the basal region of cell contains large lipid-, protein droplets and numerous glycogen granules. The basal lamina is located between the basal membrane and muscle bundle, providing barrier between the epithelium and the hemolymph. The epithelium is surround by the subepithelial space and muscles. The subepithelial space, which is composed of fibrous connective tissue is innervated by many tracheoles and axon.

• Economic and Environmental Geology
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• v.29 no.4
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• pp.421-428
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• 1996

The occurrence, optical property, chemical composition, crystal structure and formation environments of the phillipsite within deep-sea manganese nodules were systematically investigated in this study. Phillipsite in manganese nodules occurs in nucleus of nodules along with consolidated bottom sediments, weathered volcanic debris, and interstitial grains in the each layer of manganese encrusts. Phillipsite is predominantly pseudomorphs of volcanic shards, and occurs as white to pale yellow in color lath-shaped and equant crystals. These show aggregations of prismatic, blocky, and bladed of 2 to $20{\mu}m$ long, and 2 to $5{\mu}m$ thick. The simplified average chemical formula of phillipsite is $({Ca_{0.1}Mg_{0.3}Na_{1.1}K_{1.5}})_3{(Fe_{0.3}Al_{4.2}Si_{11.8})O_{32}{\cdot}10H_2O}$ with a very siliceous and alkalic. The $Si/(Al+Fe^{+3})$ ratio is 2.37 to 2.78 and alkalis greatly exceed the divalent exchangeable cations, and Na/K ratio is 0.59 to 0.81. The phillipsite is monoclinic ($P2_l/m$) with the unit-cell parameters, $a=10.005{\AA}$, $b=14.129{\AA}$, $c=8.686{\AA}$, ${\beta}=124.35^{\circ}$, and $V=1013.6{\AA}^3$. Phillipsites in manganese nodules formed apparently authigenically at a temperature less than $10^{\circ}C$, and they crystallized at a pressure of less than 0.7 kb, and pH of about 8 in deep-sea environments.

• Food Science and Preservation
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• v.21 no.2
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• pp.181-186
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• 2014

This study was conducted to that investigate the quality characteristics of wet-ground whole-grain buckwheat powder for the buckwheat husk. The particle size of buckwheat rice was 74.84 ${\mu}m$, which was approximately four to five times larger than wet-ground whole buckwheat by wet grinding. The particle size showed that there was no significant difference after 90 min on wet grinding. The total phenolics and total flavonoids contents of the whole buckwheat powder were higher than those of buckwheat rice, and they gradually increased wet grinding progressed. The rutin contents of the buckwheat increased after wet grinding and was 152.90 ppm at 90 min. There was no significant difference in the quercetin contents after wet grinding at different times. The mineral contents (Ca, K and Mg) of the whole buckwheat powder were greater than those of the buckwheat rice. Further, Zn and Mn were detected in the whole buckwheat powder. The total amino acid content of the whole buckwheat powder increased to 22.27 mg%, and the important glutamic acid increased from 14.58 to 30.45 mg%. These study results were based on 90 min wet-grinding time for whole-buckwheat-powder manufacture. Whole buckwheat powder manufactured through wet grinding can be used as an active ingredient of buckwheat husk.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.25 no.5
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• pp.218-224
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• 2015

Recently, removing methods of red tide has been attempted by filtering the organisms using the ceramic porous bodies. However, the marine biofouling could be developed on the surfaces of porous ceramic body after use for more than one month, and it might decrease the function of the specimen. In this paper, a method of inhibiting marine biofouling by changing the physical properties or surface-modification of ceramic porous body was studied. After experiment with six different ceramic porous bodies, it was found that the specimen of lower porosity and water absorption showed the least amount of biofouling. In addition, by increasing the surface roughness with silica particles bonded to the surface of specimen, the amount of biofouling caused by large marine life such as barnacle and mussel could be decreased. On the other hand, when the surface of specimen was coated and fused by glass powder, the amount of biofouling was rather increased. This might be due to eluted inorganic ions from the glass which can promote the growth of the microorganism. In conclusion, the environmental-friendly methods to reduce the amount of marine biofouling, such as controlling the physical properties and the surface roughness of the porous ceramics, can be possible without the use of dangerous substances. So it is expected for the results obtained to be applicable to a marine structure.

• Journal of the Mineralogical Society of Korea
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• v.23 no.1
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• pp.63-71
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• 2010

The artificial rains having different pH and weathering simulation test were performed for Gyeongju Namsan granite and dacitic tuff to predict the role of acid rain in the deterioration of stone monuments located in Gyeongju area. The pH 4.0 rain reacted with the fresh granite showed near neutral pH at the early stage due to the hydrolysis of minerals in the rock surface. But the pH changed back to the initial pH in the later stage. On the other hand, the pH 5.6 rain showed the neutral pH for a longer time than the experiment with pH 4.0 rain, reflecting slower reaction of minerals due to the weaker acidity. When the pH 5.6 rain reacted with the weathered granite, the water showed neutral pH longer than the case of the fresh granite. The similar tendencies were observed in the experiment of dacitic tuff, except that the pH 4.0 rain reacted with dacitic tuff took a longer time to go back to the initial pH as compared with the case of granite. These results may due to the differences in mineral composition and texture of two rocks. Dacitic tuff contains more fine-grained or glassy groundmass than granite and is more reactive with weaker acid rain. It was predicted that the weight loss and strength decrease rate of dacitic tuff would be approximatetly twice relative to those of granite in the same experimental environment.

• Resources Recycling
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• v.25 no.6
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• pp.73-81
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• 2016

Geopolymers produced from aluminosilicate materials such as metakaolin and coal ash react with alkali activators and show higher fire resistance than portland cement, due to amorphous inorganic polymer. The percentage of thermal shrinkage of geopolymers ranges from less than 0.5 % to about 3 % until $600^{\circ}C$, and reaches about 5 ~ 7 % before melting. In this study, geopolymers paste having Si/Al = 1.5 and being mixed with carbon nanofibers, silicon carbide, pyrex glass, and vermiculite, and ISO sand were studied in order to understand the compressive strength and the effects of thermal shrinkage of geopolymers. The compressive strength of geopolymers mixed by carbon nanofibers, silicon carbide, pyrex glass, or vermiculite was similar in the range from 35 to 40 MPa. The average compressive strength of a geopolymers mixed with 30 wt.% of ISO sand was lowest of 28 MPa. Thermal shrinkage of geopolymers mixed with ISO sand decreased to about 25 % of paste. This is because the aggregate particles expanded on firing and to compensate the shrinkage of paste. The densification of the geopolymer matrix and the increase of porosity by sintering at $900^{\circ}C$ were observed regardless of fillers.

• Journal of Bio-Environment Control
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• v.11 no.1
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• pp.29-34
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• 2002

An experiment was conducted to evaluate shattered industrial polyurethane (PUR) and cellular glass foam (CGF) as growth medium components. Pot chrysanthemum 'Pink Pixie Time 'was cuttured in media containing various volume ratios of PUR, CGF, peatmoss, coir, and perlite. Before plant culture, pH and EC of media were determined. Container capacity (%) was low in perlite and CGF-containing media, but it increased when incorporation ratio of peatmoss or coir was increased. pH was stable between 5.0 and 6.3, but was high in coir-contaning media as compared to other media tested. EC was very high in coir-containing media. Hight at 34 days after planting was the greatest in media containing CGF, and number. of leaves was similar among treatments. Growth in PUR-containinly media was poorer than that in the other media, with some leaf edge burning. Trends in growth measured at 97 days after planting was similar to that measured at 34 days after planting.

• Korean Journal of Food Science and Technology
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• v.16 no.4
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• pp.463-471
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• 1984

For the eventual alcohol production from uncooked starch, an efficient saccharification process was examined by using the combined action of steeping, pectin depolymerase, ${\alpha}-amylase$ and glucoamylase. The total sugar content of rice, sweet potato and tapioka used were 4.53, 4.26, and 3.92 mmole/g sample. $70\;{\pm}\;10%$ of the total sugar was hydrolyzed when cooked starch was saccharified under the condition which is currently used in industry. The smaller starch particle was used, the more saccharification was obtained. Efficient saccharification was obtained by treatment with 5% $H_2SO_4$ (sample: working volume = 1:2) at $60^{\circ}C$ for 12 hr. Optimization was carried out for the saccharification of uncooked starch by the combined action of pectin depolymerase, ${\alpha}-amylase$, and glucoamylase. The conditions are: pectin depolymerase; pH 4.5, $45^{\circ}C$, 2 hr, ${\alpha}-amylase$; pH 6.0, $60^{\circ}C$, 1 hr, and glucoamylase; pH 3.5, $60^{\circ}C$, 1 hr. Simultaneous treatment of the combined action of macerating, liquifying and saccharifying enzymes yielded better result than stepwise treatment of 3 enzymes. Degrees of saccharification of uncooked tapioka, rice and sweet potato were 82, 90.5, and 84.5%, respectively on the basis of total sugar, under the optimized conditions.