• Journal of Environmental Science International
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• v.8 no.2
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• pp.241-248
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• 1999

The photocatalytic decolorization and photodegradation of wastewater contamininated with dyes such as methyleneblue tetrahydrate(MBT), methyl orange(MO), phenol red(PR) and the mixed dyes have been studied using a batch reactor in the presence of aerotropic and titania. Degussa P25 titanium oxide was used as the photocatalyst and proved to be effective for the dyes-degradation when irradiated with UV-light source emitting the wavelength of 253.7 nm in the presence of air. In addition to removing the color from the wastewater, the photocatalytic reaction simultaneously reduced the COD and optical density which suggests that the dissolved organic compounds have been photooxidized. The reaction rate of disappearance of the dyes were measured as a function of the irradiation times. The photooxidative procedure of the aquatic solution have the first order reaction-kinetics. The rate constants were increased in the order of PR < MBT < $gL^{-1}-TiO_2$ powder were irradiated with the UV -light source.

• Journal of Environmental Science International
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• v.3 no.4
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• pp.305-315
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• 1994

The field observation was carried out to investigate the characteristics of surface inversion layer at Kimhae using the feild observed date and upper layer meteorological data during 4-5 February 1993. The results of the study can be summarized as follows : The maximum height of surface inversion layer observed at Kimhae is 193m and the height of upper level inversion layer ranges from 2nm to 300m. The surface weather elements was influenced the formation of surface inversion layer. According to the pasquill stability and time variation of temperature with height, both the surface heating from insolation and the disturbance of upper level of inversion layer was influenced the disappearance of inversion layer. And the stability of surface temperature inversion layer generally belongs to the class of F, that of upper level temperature inversion layer commonly to the class of E.

• Physical Therapy Korea
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• v.4 no.2
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• pp.51-58
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• 1997

The object of this study were twofold, namely, to study on (1) effect of using ultrasound therapy for curing warts (2) any relation between a cure for warts and onset of warts, as well as subject age. Our subjects, composed of 22 people from age 12 to 49, were assigned to two groups, experimental group and control group. We experimented for 8 session on 12 people in the experimental group by using ultrasound therapy to observe any morphological change in the warts or disappearance of a pain. However, we did not cure warts in the other group, control group. The result of the study are as follows. (1) Ultrasound therapy has an effect on curing warts. (2) Neither condition, onset of warts or subject age, had no influence on a cure for warts.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.1692-1697
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• 2004

The once-through heat recovery steam generator is ideally matched to very high temperature and pressure, well into the supercritical range. Moreover this type of boiler is structurally simpler than drum type boiler. In drum type boiler, each tube play a well-defined role: water preheating, vaporization, superheating. Empirical equations are available to predict the average heat transfer coefficient for each regime. For once-through heat recovery steam generator, this is no more the case and mathematical models have to be adapted to account for the disappearance of drum type economizer, boiler, superheater. General equations have to be used for each tube of boiler, and actual heat transfer condition in each tube has to be identified.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.31 no.7 s.262
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• pp.732-738
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• 2007

Effects of melt-mixing conditions on fracture properties of hydroxyapatite filled bioabsorbable poly(L-lactic acid)(HA/PLLA) composites was investigated by measuring the firacture toughness value of HA/PLLA composites prepared under different mixing time and rotor speed. The fracture surface morphology was also examined by profile measurement and scanning electron microscopies. It was found that the fracture toughness of HA/PLLA composites decreases due to decrease of ductile deformation of PLLA matrix and debonding of interfaces with increase of the rotor speed and mixing time. Effect of mixing process on neat PLLA was also assessed, and it was found that the fracture toughness of PLLA decreases due to disappearance of multiple craze formation and increase of defects. Such thermal and shear-stress degradation were found to be the primary mechanisms of the degradation of HA/PLLA composites during melt-mixing process.

• The Korean Journal of Nuclear Medicine
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• v.1 no.1
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• pp.79-82
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• 1967

Patients with aplastic anemia were treated with a combination of depo-testosterone cyclopentylpropionate(Upjohn) and dexamethasone. In 7 of 15 patients treated, there was response in which either a significant increase in hemoglobin concentration, a prolonged interval or a cessation of blood transfusion requirement developed during androgen therapy. Younger patients with cellular marrow appeared to be better responding to androgen. EEI(Effective Erythropoietic Index) formulated by Gardner & Nathan(1966) which was a helpful measurement as to whether patients with myelofibrosis whould respond to androgen, was evaluated in patients with aplastic anemia. It was concluded that EEI as well as ferrokinetics indices (Plasma-$^{59}Fe$-disappearance rate, RBC $^{59}Fe$ net incorporation) did not significantly correlate with the degree of response to androgen in aplastic anemia.

• Applied Microscopy
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• v.6 no.1
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• pp.1-7
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• 1976

To investigate the nature of typhoid cells, three cases of clinically, serologically and histopathologically proven typhoid lesions of the small intestine and regional lymph nodes were studied light and electron microscopically, Light microscopically, typhoid cells were swollen mononuclear cells characterized by abundant amount of eosinophilic cytoplasm and frequent phagocytoses of red blood cells, bacterial clumps and other tissue debris. These cells were pyronin negative, Electron microscopically, these cells showed marked and diffuse dilatation of RER cisternae and disappearance of ordinary cytoplasmic organelles, but frequent phagocytosed materials, The meaning and reason of RER cisternal dilatation and reduction of cytoplasmic organelles were discussed, and are regarded as degenerative process due to bacterial endotoxin. Although there was hot enough cytoplasmic organelles to pinpoint the origin of typhoid cells, active phagocytosis and evidences against being either plasmacytic or lymphocytic nature favored retuculoendothelial nature of the typhoid cells.

• Laser Solutions
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• v.1 no.1
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• pp.30-38
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• 1998

This study includes the efface of shielding gas types on $CO_2$ laser weldability of low carbon automotive galvanized steel. The types of shielding gas evaluated are He, $CO_2$, Ar, $N_2$, 50%Ar＋50%$N_2$. The weld penetration, strength, formability(Erichsen test) of Laser weld are found to be strongly dependent upon the types of shielding gas used. Further, the maximum travel speed and flow rate to form a keyhole weld is also dependent upon types of shielding gas. The ability of shielding gas in removing plasma plume and thus increasing weld penetration is believed to be closely related with ionization/dissociation potential, which determine the period of plasma formation and disappearance. Further, thermal conductivity and reactivity of gas with molten pool also give strong effect on penetration and porosity formation which in turn affect on the formability and strength.

• Analytical Science and Technology
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• v.9 no.1
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• pp.62-71
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• 1996

The enhancement of the solar energy conversion efficiency into the electrical energy by the dye sensitization with a photoelectrochemical cell was studied. The magnitude of the rose bengal sensitized photocurrent containing the supersensitizer, thiourea was five times greater than that in the absence of thiourea. It was observed, however, that the long time span of irradiation causes the decrease in the photocurrent. Spectroscopic analysis of the dye solution showed that the dye molecule was photobleached and the insoluble aggregate which settles down in the solution, was formed as a result of the possible photocatalytic reaction and the disappearance of dye from the solution was the cause of the decreased photocurrent in the sensitization run.

• Journal of Sericultural and Entomological Science
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• v.37 no.1
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• pp.62-67
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• 1995

Ultrastructural changes of tissues caused by Bacillus thuringiensis var. kurstaki $\delta$-endotoxin intoxication of Hyphantria cunea were observed by transmission electron microscopy. Bt $\delta$-endotoxin crystals induced the disruption of microvilli, vacuolation of cytoplasm, changes in the cisternae of the endoplasmic reticulum, disappearance of basal striations, loss of ribosomes, and changes in the configurations of mitochondria in the columnar cell of midgut. The fat body cells also showed spherical endoplasmic reticulum and distorted mitochondria, and then the cells were destroyed.