• Journal of Sensor Science and Technology
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• v.5 no.3
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• pp.101-108
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• 1996

The silicon $p^{+}-n$ junction diodes were fabricated. The fabricated wafers were treated by single or double annealing steps. Single annealing process was performed by diffusion of either Au or Pt into the wafer under the oxygen or nitrogen ambient at $800{\sim}1010^{\circ}C$. Second annealing step involved additional annealing of the single annealed wafer under the oxygen ambient at $800{\sim}1010^{\circ}C$ for one hour. Electrical characteristics of the diodes were investigated to evaluate the effect of the annealing treatments. In the case of single annealing under nitrogen ambient at $1010^{\circ}C$ for one hour, the amount of leakage current of Pt diffused diode was 75 times larger than that of Au diffused one. The optimum processing condition to achieve high speed silicon $p^{+}-n$ junction diodes from this study was obtained when Pt diffused wafer(treated under the nitrogen ambient at $1010^{\circ}C$ for one hour) was secondly annealed in an oxygen ambient at $800^{\circ}C$ for one hour. The resulting leakage current of two step annealed diodes were remarkably reduced to 1/1100 of the single annealed one. The diode characteristics such as recovery time, breakdown voltage, leakage current, and forward voltage were 4ns, 138V, 1.72nA, and 1V, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.9 no.1
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• pp.39-45
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• 1976

The content of nitrogen, phosphorus, potassium, calcium and magnesium of hulled barley grown on farmer's field with various N.P.K rates were investigated at various growth stages. Correlation analyses between N.P.K contents and yield and use efficiency of N.P.K and other results were as follows. 1. According to concentration and its change at various growth stages N is similar to K and P, Ca, Mg are similar each other. 2. Yield showed significant positive correlation in most fields with nitrogen content just after thawing. However P and N content were more significantly correlated with yield just before freezing in Kangwon and Chungnam (northern and central province). At the other growth stages negative correlation trend was shown between yield and P, especially K. 3. N.P.K contents in plant increased with the increase of fertilizer rate clearly in early growth stage, and especially in nitrogen, indicating that N was relatively short than P and K in the later stage. N and K contents at various fertilizer rates also indicated a probable competition between them. 4. Fertilizer recovery (use efficiency) decreased in the order of N (55)>K (27)>P (12%) and that of N tended to increase with yield increase. 5. Most effective growth stage for nutritional diagnosis in relation to yield appears to be just after thawing or just before freezing. Nutritional criteria for N.P.K at various growth stages were proposed.

• KSBB Journal
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• v.19 no.4
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• pp.245-249
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• 2004

A combined method of autolysis and enzymatic hydrolysis of baker's yeast was developed for the production of yeast extract, which is widely used as a natural food ingredient. From statistical analysis, NaCl and ethanol addition were found to be significantly effective factors in autolysis of yeast. The optimum dosages of salt and ethanol were 3% and 1%, respectively. Heat treatment and the use of cell lytic enzyme were not significantly effecting on the autolysis. Yeast hydrolysate was prepared by autolysis, followed by enzymatic hydrolysis using proteases, nuclease and deaminase. Additionally, the hydrolysate was processed by downstream process including Maillard reaction and debittering. The total dry matter yield and total nitrogen yield for the process were 76% and 59%, respectively. Compared to a process using brewer's yeast, when baker's yeast was used as a raw material, a higher recovery yield was obtained.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.10a
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• pp.16.1-16.1
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• 2011

Gas sensor properties of $WO_3$ nanowire structures have been studied. The sensing layer was prepared by deposition of tungsten metal on porous single wall carbon nanotubes followed by thermal oxidation. The morphology and crystalline quality of $WO_3$ material was investigated by SEM, TEM, XRD and Raman analysis. A highly porous $WO_3$ nanowire structure with a mean diameter of 82 nm was obtained. Response to CO, $NH_3$ and $H_2$ gases diluted in air were investigated in the temperature range of $100{\sim}340^{\circ}C$ The sensor exhibited low response to CO gas and quite high response to $NH_3$ and $H_2$ gases. The highest sensitivity was observed at $250^{\circ}C$ for $NH_3$ and $300^{\circ}C$ for $H_2$. The effect of the diameters of $WO_3$ nanowires on the sensor performance was also studied. The $WO_3$ nanowires sensor with diameter of 40 nm showed quite high sensitivity, fast response and recovery times to $H_2$ diluted in dry air. The sensitivity as a function of detecting gas concentrations and gas sensing mechanism was discussed. The effect of dilution carrier gases, dry air and nitrogen, was examined.

• Korean Journal of Pharmacognosy
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• v.29 no.4
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• pp.379-383
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• 1998

Sodium arsenate and Paljin-Tang extract (PJT), a herbal restorative were treated p.o. 20 mg/kg and 500 mg/kg, respectively, and concurrently to rats, and examined the biochemical parameters in blood. The values of white blood cell (WBC), red blood cell (RBC), hemoglobin (Hgb) and hematocrit (Hct) in each group did not show significant variance. The value of aspartate aminotrasferase(AST) of arsenic-treated group was increased for 2 weeks significantly while that of the group of concurrent administration with PJT became low significantly compared with arsenic-treated group and the value of alkaline phosphatase (ALP) of arsenic-treated group was decreased while that of the group of concurrent administration with PJT was increased significantly compared with arsenic-treated group. The value of glucose (Glu) was increased and those of lactic dehydrogenase (LDH), blood urea nitrogen (BUN) and triglyceride (TG) were decreased at first but increased later while the group of concurrent administration with PJT showed significant recovery from the toxicity of arsenic.

• Journal of Microbiology and Biotechnology
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• v.16 no.3
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• pp.414-422
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• 2006

Before applying PVA bio-beads to practical biological treatment of nitrate-containing wastewater, their characteristics were examined. PVA bio-beads could steadily produce nitrogen gas from nitrate for 28 batches with 0.04 ml/l/h of the maximum gas production rate; however, the maximum gas production rate dropped remarkably thereafter with apparent deformation of beads. Addition of 2.2% solution containing 1% casamino acid, 1% yeast extract, 0.1% mineral solution, and 0.1% vitamin solution to the culture medium resulted in not only recovery of activity of deactivated beads, but also a higher rate of gas production. Calculation of economic benefit for the use of bio-beads in a long-run operation indicated that reactivation of bio-beads by chemicals had economical advantages over packing new bio-beads in the system. The continuously stirred bioreactor exhibited a satisfactory performance at HRT of 20.0 h. With a 9.5 mg $NO_{3}^{-}N/l/h$ nitrate removal rate, nitrate could completely be removed without nitrite accumulation. The use of PVA bio-beads in nitrate removal appears very promising.

• Korean Journal of Food Science and Technology
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• v.49 no.1
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• pp.104-109
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• 2017

The present study was conducted to evaluate the anti-inflammatory and anti-arthritic effects of fermented Achyranthes japonica (Miq.) Nakai extract (FAJE). The FAJE was effective in nitrogen oxide (NO) scavenging in RAW264.7 cells. In the case of experimental Sprague Dawley (SD) rats injected with monosodium iodoacetate (MIA), the levels of $TNF-{\alpha}$ and $IL-1{\beta}$ in blood increased in the osteoarthritis-induced group while decreasing in the group administered with FAJE. In addition, MMP-2 and MMP-9 in cartilage tissues increased in the osteoarthritis-induced group, but decreased in the group treated with FAJE. Cartilage examination indicated that the osteoarthritis-induced group exhibited cartilage erosion and cell degeneration, but in the FAJE administered group the tissue, conditions were recovered and cartilage proteoglycan was increased. Therefore, FAJE clearly showed anti-inflammatory effects and this suggests it is effective for recovery from osteoarthritis induced by MIA.

• Fisheries and Aquatic Sciences
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• v.14 no.3
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• pp.205-209
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• 2011

Organic pollution causes eutrophication and dystrophication, which occur when excessive amounts of organic matter enters seawater. Eutrophication can contaminate sediment and harm aquaculture. Polychaeta species have been shown to restore eutrophic sediment. In this study, we used peptone to simulate a eutrophic environment and detect the levels at which eutrophication became toxic to the polychaete Perinereis aibuhitensis. Peptone concentrations were 0, 100, 200, and 500 mg/L. The median lethal concentrations were 950.35 mg/L at 48 h, 340.34 mg/L at 72 h, and 120.22 mg/L at 96 h, which are much higher than those of other aquatic species. Polychaeta species are highly tolerant of eutrophication. During the 15-day long-term experiment, sediment loss on ignition, as well as seawater total organic carbon and total nitrogen all decreased significantly (P<0.05). However, $NH_4^+$ concentration increased with time. Perinereis aibuhitensis slowed the increment of $NH_4^+$ but could not prevent its increase. Our results indicate that this polychaete is helpful in the recovery of seawater and sediment from eutrophication.

• Bulletin of the Korean Chemical Society
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• v.34 no.3
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• pp.851-855
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• 2013

This paper describes an environmentally friendly process for the recovery of $LiFePO_4$ cathode materials from scrap electrodes by a simple thermal treatment method. The active materials were easily separated from the aluminum substrate foil and polymeric binders were also decomposed at different temperatures ($400^{\circ}C$, $500^{\circ}C$, $600^{\circ}C$) for 30 min under nitrogen gas flow. The samples were characterized by X-ray diffraction (XRD), scanning electronic microscopy (SEM), Raman spectroscopy, Thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The electrochemical properties of the recycled $LiFePO_4$ cathode were evaluated by galvanostatic charge and discharge modes. The specific charge/discharge capacities of the recycled $LiFePO_4$ cathode were similar to those of the original $LiFePO_4$ cathode. The $LiFePO_4$ cathode material recovered at $500^{\circ}C$ exhibits a somewhat higher capacity than those of other recovered materials at high current rates. The recycled $LiFePO_4$ cathode also showed a good cycling performance.

• Biomedical Science Letters
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• v.11 no.3
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• pp.407-416
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• 2005

Cardiopulmonary bypass (CPB) for cardiac surgery induces the production and release of numerous chemotactic substances and cytokines, ensuing systemic inflammatory response that causes postoperative major organ dysfunctions. We performed a randomized, prospective study to investigate clinical effects of preoperative treated-methylprednisolone for preventing inflammation in pediatric cardiac surgery with CPB. Thirty pediatric patients scheduled for elective cardiac surgery were randomized to either control(n=15) or steroid group (n=15, 10 mg/kg of methylprednisolone). Arterial blood samples were taken before and after the operations for measuring total leukocyte (T-WBC) and differential counts, platelet counts, interleukin-6 (IL-6), myeloperoxidase (MPO), neuron specific enolase (NSE), troponin-I (TNI), aspartate aminotransferase (AST), alanine aminotransferase (ALT), blood urea nitrogen (BUN), and creatinine levels. Postoperative parameters such as pulmonary index (PI, $PaO_2/FiO_2$), 24 hrs and total bleeding volumes, mechanical ventilating (MVP) and intensive care unit (ICU)-staying periods, and hospitalization were assessed. T-WBC, neutrophil fraction, IL-6, MPO, NSE, TNI, AST and creatinine levels, bleeding volumes, PI, and MVP at the postoperative periods were lower or shorter in steroid group than in control group (P<0.05). These findings indicated that preoperative administration of methylprednisolone attenuated CPB-induced inflammatory reactions, contributing to postoperative recovery of patients underwent cardiac surgery.