• Journal of Pharmaceutical Investigation
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• v.41 no.4
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• pp.217-225
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• 2011

The aim of this work was to prepare porous osmotic pump tablets for controlled delivery of Aceclofenac. Aceclofenac solid dispersion was prepared to improve the solubility by using the drug - carrier (Mannitol) ratio of 1:1. The osmotic pump tablets were prepared using the solid dispersed product of Aceclofenac. The formulation contains potassium chloride as osmotic agent, cellulose acetate as semipermeable membrane, poly ethylene glycol (PEG 4000) as pore former and sodium lauryl sulphate (SLS) as solubility enhancer. The formulations were designed by the general factors such as osmotic agent and pore former. All formulations were evaluated for various physical parameters and, the in vitro release studies were conducted as per USP. The drug release kinetic studies such as zero order, first order, and Higuchi and Korsmeyer peppas were determined and compared. All the formulations gave more controlled release compared to the marketed tablet studied. Numerical optimization techniques were applied to found out the best formulation by considering the parameter of in vitro drug release kinetics and dissolution profile standards. It was concluded that the porous osmotic pump tablets (F7) composed of Aceclofenac solid dispersion/Potassium chloride/Lactose/Sodium lauryl sulphate/Magnesium Stearate (400/40/95/10/5, mg/tab) and coating composition with Cellulose acetate/ PEG 4000 (60/40 %w/w) is the most satisfactory formulation. The porous osmotic pump tablets provide prolonged, controlled, and gastrointestinal environment-independent drug release.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1471-1472
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• 2011

최근 경재적인 한계를 드러내고 있는 실리콘 태양전지의 대안으로 주목받고 있는 염료감응형 태양전지는 식물의 광합성 원리에 기초하여 빛이 입사하면 염료 분자가 포톤을 흡수해 여기하면서 전자를 방출함으로써 기전력을 발생시키는 원리로 동작한다. 염료에서 발생된 전자는 $TiO_2$의 conduction band로 주입되어 확산을 통해 TCO 기판으로 이동한다. 이때 다공성 나노구조의 $TiO_2$ 표면과 전해질의 접촉이 발생하게 되고 이로 인해 $TiO_2$ conduction band의 전자와 전해질의 $I_3{^-}$ 간의 재결합이 발생하게 되는데 이것은 DSC의 기능을 저하시키는 요인 중의 하나이다. 이러한 문제점은 $Al_2O_3$, ZnO, MgO, $BaTiO_2$ 등의 표면처리에 의한 core-shell 나노구조를 형성함으로써 해결할 수 있다. 본 연구에서는 aluminum isopropoxidee와 magnesium chloride 혼합 용액을 사용하여 core-shell 나노구조를 형성하여 셀을 제작하고, 완성된 셀의 출력특성과 내부 임피던스의 변화를 측정, 분석함으로써 단일 용액을 사용하였을 때에 비해 효과적인 재결합 감소와 광전압의 상승효과를 확인할 수 있었다.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.1
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• pp.24-31
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• 2010

This study was carried out to analyze vegetation and soil characteristic, and ordination of Scrophularia takesimensis population, Ulleung Island. The Scrophularia takesimensis population was classified into Aster spathulifolius for. oharai dominant population, Vitis amurensis dominant population and Scrophularia takesimensis typical population. The Scrophularia takesimensis population was located in elevation of 1m to 6m, in Ulleung Island. In the study sites, soil organic matter, nitrogen, available phosphorous, exchangeable potassium, exchangeable calcium, exchangeable magnesium and exchangeable sodium concentration, and cation exchange capacity, and soil pH were 9.1~19.1%, 0.19~0.52%, 87.1~196.7mg/kg, 2.0~2.8cmol+/kg, 5.4~5.9cmol+/kg, 5.9~8.8cmol+/kg, 4.4~4.8cmol+/kg, 20.3~26.7cmol+/kg, and 6.8~8.0, respectively. The Vitis amurensis dominant population was mainly found in the high percentage of total nitrogen, organic matter, CEC in comparison with Aster spathulifolius for. oharai dominant population.

• Journal of the Korean Society for Heat Treatment
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• v.28 no.6
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• pp.315-321
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• 2015

Friction stir processing (FSP) was applied to fabricate AZ31/CNT (Carbon Nano Tube) surface composite for improvement of surface hardness of AZ31 Mg-based alloy. The effects of traverse speed of rotating tool and volume fraction of CNT (i.e., groove depth of 3 mm and 4 mm) on the soundness and hardness of the composite layer were investigated. Multi-walled CNTs were fully filled in a machined groove and stirring tool was rotated at the speed of 1400 rpm. Only under the tool traverse speed of 25 mm/min for the specimen with a groove depth of 3 mm, surface composite layer with no defect was successfully produced. Increased hardness of about 35% was observed in the composite layer.

• Microbiology and Biotechnology Letters
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• v.7 no.2
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• pp.65-70
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• 1979

By the successive enrichment culture, methanol-utilizing bacteria of 213 strains were isolated from soil samples collected from various places. Among them one strain showing excellent growth was selected. The organism isolated was obligate methylotroph and identified as Methylomonas methanolica on the basis of its mophological and physiological characteristics of the cell. The medium have been to be collected for the maximum biomass productivity. The microorganism was capable of growing satisfactorily on a medium containing only methanol 0.8％ (v/v), ammonium sulfate 0.6％, magnesium sulfate 0.1％, phosphate salts, but did not require growth factor.

• Applied Biological Chemistry
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• v.39 no.1
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• pp.67-69
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• 1996

Some physical properties and inorganic components of sap from sponge-gourd(Luffa cylindrica L.) were investigated for their changes affected as collection time. Huter valves, pH, turbidity and viscosity of the sap were not different. pH value was indicated at slightly alkalinity and decreased by culturing period. Potassium, calcium and magnesium were major inorganic components of the sap and podium, zinc and iron were minor components. Copper was not detected in open culturing and also manganes way not detected in all samples.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.6
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• pp.908-913
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• 2007

Concentrations of major elements in forages were determined in relation to ruminant requirements at a livestock experimental station in Leiah district, Punjab-Pakistan using mapping techniques. The study investigated the influence of sampling periods and pasture types on the concentrations of calcium, magnesium, potassium, and sodium in forages. The implications of these forages for nutrition of ruminants were assessed for the livestock population at that particular experimental station, which are supported by the farm pastures. Within the farm, variations in the element status of the forages were related to soil pasture types. A tentative assessment of the mineral status of available forages at this farm for different pastures using guidelines developed for domestic animals indicated deficiencies of only Na, but forages contained adequate Ca, Mg, and K levels required for grazing ruminants. The concentrations of Na in the forage reserves indicated that the potential supply of this element to plants was limited from the soil to plants and from plants to the animals grazing them. Soil minerals were not measured in this study. The potential use of fertilizers, as pasture amendment as well as supplementation of ruminants, with a specifically tailored mineral mixture is important to livestock producers and environmentalists as well, because their use may improve forage nutritive value and in turn meet requirements of animals.

• The Korean Journal of Ecology
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• v.26 no.6
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• pp.327-333
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• 2003

A mixed forest of pines (Pines densiflora and Pinus rigida) and an oak forest (Quercus mongolica) in Mt. Kwanak in Seoul were limed with 1.5 t/ha and 3 t/ha of dolomite in 1993 and investigated the effects of liming on the chemical changes in the 0-5 cm and 5∼10 cm layers of soil from 1994 to 1995. Soil pH values were greater in the limed plots than in the control plot by the unit of 0.1-0.6 in the pine forest and 0.1∼0.2 in the oak forest. Ca concentrations in the limed plots were greater than those in the control plots in both the pine and oak forests. A considerable increase in Mg concentrations in soil was observed in the limed plots. K and Na concentrations in the limed plots appeared to decrease in both the pine and oak forests two years after liming. Although Al concentrations were greater in the limed plots than in the control plot in the pine forest in 1994, there was a tendency of a decrease in the concentration of this metal in the limed plots in 1995. Mn concentrations also tended to decrease in the limed plots in both the pine and oak forests.

• Journal of Aquaculture
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• v.18 no.3
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• pp.196-199
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• 2005

Farmed red sea breams, Pagrus major, were fed for 60 days with pellets containing different concentrations of benzo(a)pyrene (0, 0.2, 2, 20 mg/kg) to generate a biomarker of the chemical toxicity in the fish. The fish exposed to the chemical concentrations did not show any significant difference in the weight gain, conditioning, factor, and hepatosomatic index. However, some haematological parameters, such as glucose, calcium, magnesium, GOT (glutamic oxalate transaminase), and GPT (glutamic pyruvate transaminase) were influenced by the chemical exposure. Of them, two enzymes, GOT and GPT, increased significantly 60 days after the exposure in a way of concentration dependence (P<0.05). In the study of ecotoxicological biomarker, sensitivity to adverse environments is one of the key available factors. The fish changes in GOT and GPT were an earlier and reliable sign of the fish response against the chemical exposure, rendering the two enzymatic factors as a useful biomarker at least to benzo(a)pyrene exposure in the farming waters.

• Fisheries and Aquatic Sciences
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• v.20 no.3
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• pp.4.1-4.6
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• 2017

Juvenile Anoplopoma fimbria (mean length $16.8{\pm}2.2cm$, and mean weight $72.8{\pm}5.4g$) were exposed for 2 months with different levels of ammonia (0, 0.25, 0.50, 0.75, 1.00, and 1.25 mg/L). Growth performances such as daily length gain, daily weight gain, condition factor, and hepatosomatic index were significantly decreased by ammonia exposure. Hematological parameters such as red blood cell (RBC) count, hematocrit, and hemoglobin were also significantly decreased. In plasma inorganic components, calcium and magnesium were significantly decreased by ammonia exposure. In plasma organic components, there was no alteration in cholesterol and total protein. In enzyme plasma components, glutamic oxalate transaminase (GOT) and glutamic pyruvate transaminase (GPT) were significantly increased. The results of this study indicated that ammonia exposure can induce significant growth reduction and blood biochemistry alterations of A. fimbria.