• Journal of the Korean Magnetics Society
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• v.2 no.3
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• pp.216-221
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• 1992

Annealing effects on the permeability aftereffect(disaccommodation) of liquid quenched single strip $Fe_{73.5}Cu_1Nb_3Si_{16}B_{6.5}$ alloys were investigated with pulse method. The initial susceptibility X, $B_{10},$ (the flux density at 10 Oe) and disaccommodation intensity D (D = [X(1 s)-X(64 s)]/X(1 s), where X(1 s) and X(64 s) are the susceptibility of 1 and 64 s of rest time after A. C. demagnetization) were about 800, 0.8 T and 16 %, respectively. The soft magnetic properties were improved with isothermal annealing for 1 hour at $300{\sim}600^{\circ}C.$ X, $B_{10},$ and D at $570^{\circ}C$ of optimum annealing temperature were 15000, 1.2 T and 1.1 %, respectively. The origin of the change of characteristics were examined with fine crystalline structure and magnetostriction.

• Korean Journal of Microbiology
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• v.50 no.2
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• pp.158-163
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• 2014

In the acidic LB plate, a bacterial strain was isolated from homemade soybean paste as a producer of the extracellular mannanase. The isolate YB-1402, which was a Gram-positive rod-shaped bacterium with spore, has been identified as Bacillus amyloliquefaciens on the basis of its 16S rDNA sequence and biochemical properties. Maximum mannanase productivity of the isolate YB-1402 was reached approximately 150 U/ml in LB broth supplemented with konjac (3.0%). The molecular mass of YB-1402 mannanase was estimated to approximately 38.0 kDa by zymogram of the culture filtrate on SDS-PAGE. The mannanase of culture filtrate was the most active at $55^{\circ}C$ and pH 5.5. The mannanase activity was completely maintained after pre-incubation at pH 3.0 to 10.0 for 1 h. The predominant products resulting from the mannanase hydrolysis were mannose, mannobiose and mannotriose for LBG or mannooligosaccharides. The enzyme could hydrolyze mannooligosaccharides larger than mannobiose.

• Journal of the Korean Wood Science and Technology
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• v.44 no.5
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• pp.622-628
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• 2016

This study investigated to understand the trend of international commercializing technologies and industrial status of the transportation biofuel based on lignocellulosic biomass. Two major commercializing technologies for the lignocellulosic biofuel are biochemical conversion technology and thermochemical conversion technology. It was reported that a total of 93 industrial companies were using lignocellulosic biomass of all facilities related to advanced biofuel. On the basis of commercial type, the biochemical conversion technology was identified to be the major technology in the lignocellulosic biofuel industries, showing 84% of all. Also the main products of commercial type industrial companies are bioethanol (1,155,000 tons/yr) and bio-oil (120,000 tons/yr), which are in a remarkably inadequate amount to substitute for the transportation biofuel worldwide. It was suggested that the transportation biofuel market was currently in need of further development in both technology and scale, and was in high demands of technological development and commercializing exertion.

• KSBB Journal
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• v.14 no.1
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• pp.124-130
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• 1999

To evaluate the technical of microbial coal desulfurization during the storage in coal dumps, microbial pyrite oxidation in a packed column reactor with Thiobacillus ferrooxidans has been investigated. For microbial desulfurization in a packed reactor system, coal particle size over 1.0 mm with uniform size distribution seems to be most suitable as fas as drainage behavior and accessability of pyrite are concerned. When coal samples of 1∼2 and 2∼4 mm particle size were size were used, about 32∼42% of pyritic sulfur was removed within 70 days. The rate of pyritic sulfur oxidation was in the range of 348∼803 mg S/kg coal ·d, and the sulfur removal rates in packed columns were about 15∼25% of those in suspension cultures. Without any circulation of liquid medium, microbial coal desulfurization could be possible by the inoculation of T. ferrooxidans along on the coal dump. It was concluded that a microbial percolation process is one of possible processes for the desulfurization of high sulfur coal during a long-term storage.

• Journal of Conservation Science
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• v.21
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• pp.33-40
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• 2007

The consolidation application of SILRES BS OH 100 was investigated, which has been used for consolidation of the weathered shale. The liquid SILRES BS OH 100 was polymerized by the sol-gel reaction with air moisture, and the XRD patterns showed that the gel was an amorphous solid. The drastic weight reduction of the sample was found by differential thermal analysis, which was followed to the formation of $Si(OH)_4$ particles. After consolidation, the polymerized gel was filled into the voids within the shale. The capillary water absorption of the consolidated shale was reduced to 48.7%, and the abrasive strength was improved.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.05a
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• pp.149-152
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• 2008

Effects of chamber configuration on combustion characteristic velocity of full-scale combustion chamber for 30-tonf-class liquid rocket engine were studied. The configurations of combustion chamber are ablative and channel cooling chamber (${\varepsilon}$=3.2) which have detachable mixing head, and single body regenerative cooling chamber which has nozzle expansion ratio of 3.5 and 12, respectively. The combustion chambers have chamber pressure of 53${\sim}$60 bar and propellant mass flow rate of 89 kg/s, and the injectors of all combustion chamber have recess number 1.0 and double-swirl characteristics. The hot firing test results at design point show that the combustion characteristic velocity of the regenerative cooling chamber which has nozzle expansion ratio of 12 is higher than that of other combustion chambers. The reasons for the above result are the increases of combustion pressure and enthalpy of kerosene which is heated due to cooling of the chamber wall before injection into the combustion field.

• Korean Journal of Food Science and Technology
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• v.24 no.1
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• pp.97-100
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• 1992

Tofu-residue (biji) which was made on a laboratory scale from the three U.S. and three Korean soybean varieties contained approximately 57% dietary fiber, 20% protein, while the commercial residue contained 59% dietary fiber and 17% protein. The percent soluble fiber in total dietary fiber were 3% and 46% for residue and tofu, respectively. The tofu-residue was wet milled by blade grinding once or twice, followed by sieving and centrifugation of the liquid fraction. For twice-ground residue, the dietary fiber content increased from 58.70 to 80.6% in the sieved residue, with a fiber recovery of 90.4%. On the other hand, twice-ground centrifuged solids contained 46.8% protein, representing 42.4% of the total protein. Lipid levels in the sieved residue were much lower than in the original residue.

• Journal of Yeungnam Medical Science
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• v.1 no.1
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• pp.179-183
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• 1984

In recent years, an increasing number of drugs have been reported to cause direct esophageal damage. More than 30 cases on tetracyclines induced esophageal ulcer have been reported since the first description of tetracycline induced esophageal ulcer by Bokey and Hugh in 1975. In Korea, only one case of doxycycline-induced esophageal ulcer has been reported. Authors have experienced 3 cases of esophageal ulcer probably caused by tetracyclines. The patients had taken their capsules just before going to bed with little fluid intake. About 6-8 hours later they had felt substernal burning sensation and epigastric discomfort. Gastrofiberscopy revealed relatively well demarcated circular ulcers on the mid esophagus. An esophagogram showed no apparent abnormality. Patients's symptomas became negligible with antacid treatment within 2-5 days. One of the causes of the esophageal ulcer is thought to be the delay in transit time of drugs and direct esophageal damage from mucosal contact when tablets are ingested in the recumbent position without an accompanying proper quantity of fluid. If only physicians endow patients with more concern about drug induced esophageal ulcer, they could find out more increasing number of drug induced esophageal ulcers by gastroscopic examination and thereby could prevent tetracycline induced esophageal ulcer.

• KSBB Journal
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• v.8 no.2
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• pp.150-155
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• 1993

This study describes biodegradation of dyes which are used in textile industries. Dyes released into the environment from industrial waste water are considered to be a serious pollution problem because of the wide spread into environment with a variety of colors. The microorganisms used in this experiment were Pseudomonas species, which had been screened from aeration tank of waste water treatment. It was found that optimum concentrations for culture media were 14g of glucose, 6g of peptone, 160 mg of Na2HPO4, 200mg of KCl, 140mg of MgSO4,.7H2O,1.0g of KH2PO4, 400mg of NaCl, 200mg of CaCl2 and dye 10ppm per litre of distilled water. The high efficiency of dye degradation was obtained at pH 7-8 and $30-35^{\circ}C$. Strains screened are excellent for removal of azo and reactive dyes, which are relatively stable and difficult to degrade. Dyes of 10ppm such as mono-azo (Lot No. 180), di-azo (Lot No. 138) and reactive red(Lot No. 2) were mostly decolorlzed within 2 days and di-azo (Lot No. 151) and reactive red(Lot No. 34, No. 00166) were decolorized within 5 days in the controlled fermenter. In the case of reactive dyes, oxygen supplies showed lower biodegradability compared to anaerobic culture.

• Applied Biological Chemistry
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• v.29 no.1
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• pp.44-50
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• 1986

Two fractions of ${\beta}-glucanase$(CMCase), two fractions of filter paper degradation enzyme (FPase) and one ${\beta}-glucanase$ fraction were partially purified from Fusarium moniliforme and applied to recovery process of red bean starch. Red bean were incubated with the fractions of CMCase and FPase at $50^{\circ}C$ for 2 hours and the starch granules are separated. Maximal sedimentation rate of red bean starch granules was obtained with treatment of the mixture solution of 0.004 units/ml of FPase and 0.3 units/ml of CMCase. In the enzyme treated process percent recovery of red bean starch granule increased about 7% and suspended solid in waste water was reduced about 40%, compared with those of control. The results indicated that red bean cell treated with cellulase fractions absorbed water more rapidly and specific gravity of starch granule increased.