• Economic and Environmental Geology
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• v.51 no.5
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• pp.401-407
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• 2018

For the treatment of heavy metals in the mine drainage from the closed mine area, various methods such as passive, active and semi-active treatments are considered. Among contaminated elements in the mine drainage, Mn is one of the difficult elements for the treatment because it needs high pH over 9.0 for its concentration to be reduced. In this study, the efficiency of various slag complex reactors (slag (S), slag+limestone (SL) and slag+Mn coated gravel (SG)) on Mn removal in the presence of Fe, which is a competitive element with Mn, was evaluated to investigate effective methods for the treatment of Mn in mine drainage. As a result of experiments on Mn removal without Fe during 358 days, using influent with $30{\sim}50Mn{\cdot}mg/L$ and pH 6.7 on the average, S reactor showed continuously high Mn removal efficiency with the average of 99.9% with pH 8.9~11.4. Using the same reactors, Mn removal experiments with Fe during 237 days were conducted with the influent with $40{\sim}60Mn{\cdot}mg/L$. The pH range of effluent reached to 6.1~10.0, which is slightly lower than that of effluent without Fe. S reactor showed the highest range of pH with 7.1~9.9, followed by S+L and S+G reactor. However, the efficiency of Mn removal showed S+L>S>S+G with the range of 94~100%, 68~100% and 68~100%, respectively in spite of relatively low pH range. S+L reactor showed the most resistance on Fe input, which means other mechanisms such as $MnCO_3$ formation by the carbonate prouced from the limestone or autocatalysis reaction of Mn contributed to Mn removal rather than pH related mechanisms. The evidence of reactions between carbonates and Mn, rhodochrosite ($MnCO_3$), was found from the X-ray diffraction analysis of precipitates sample from S+L reactor. From this study, the most effective reactors on Mn removal in the presence of Fe was S+L reactor. The results are expected to be applied for the Mn containing mine water treatment in the presence of Fe within the relatively low range of pH.

• Korean journal of applied entomology
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• v.39 no.1
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• pp.53-58
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• 2000

The effect of NeemAzal-T/S was tested by leaf disk method on fecundity, egg mortality, and preference of twospotted spider mite, Tetranychus urticae and its predator mite, Amblyseius womersleyi in the laboratory. Mortalities of T. urticae and A. womersleyi adults were 97.7% and 20.0%, in 100ppm treatment at 72 h after application, respectively. The mean number of eggs laid per T. urticae female adult were 0.0 and 18.5, and those of A. womersleyi were 1.6 and 2.9 at 100 ppm and 0 ppm concentrations, respectively. Hatchability of T. urticae eggs treated with 50 and 100 ppm were 52.8%, and 2.5%, respectively, and those of A. womersleyi eggs were 100% and 91.3%, respectively. Choice and no-choice tests revealed that T. urticae female preferred to alight and oviposit on untreated bean leaf disk with 13.8 to 18.2 eggs per female. In contrast, A. womersleyi female preferred on treated or untreated bean leaf equally. There was no significant differences in the number of consumption of T. urticae eggs by A. womersleyi on treated and untreated bean leaves, except 200 ppm. These results indicate that NeemAzal-TIS is highly toxic to T. urticae, and is less toxic to A. womersleyi. It may be concluded with these results that NeemAzal-T/S could be incorporated into integrated T. urticae management system.

• Journal of Advanced Navigation Technology
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• v.12 no.2
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• pp.122-131
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• 2008

In this paper, an S-band oscillator of the low phase noise property using miniaturized microstrip hairpin shaped ring resonator has been designed and implemented. The TACONIC's RF-35 substrate has a dielectric constant ${\varepsilon}_r$=3.5 a thickness h=20mil a copper thickness t=17 um and loss tangent $tan{\delta}$=0.0025. The designed and implemented 2.45 GHz oscillator shows low phase performance of -100.5 dBc/Hz a 100kHz offset. Output power 20.9 dBm at center frequency 2.45 GHz and harmonic suppression -32 dBc. The circuit was implemented with hybrid technique. But can be fully compatible with the RFIC's, MIC and MMIC due to its entirely planar structure.

• Korean journal of food and cookery science
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• v.15 no.6
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• pp.611-617
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• 1999

Commercial soybean oil, which did not contain any antioxidant, were autoxidized at $60{\pm}2^{\circ}C$ for 79 days, and the changes of peroxide value(POV), thiobarbituric acid value(TBAV), conjugated dienoic acid(CDA) content, and fatty acid composition of the oil were studied during the 79 day-storage period. The samples with POV S of 0, 150, 300, 500, 450, 400 and 300 meq./kg oil were used for the test of mutagenic activity. The Ames test was carried out with and without metabolic activation. Bacterial strains used in this study were the histidine auxotrophic strains of S. typhimurium TA100, TA1535, and TA102 for the detection of base pair, and TA98 and TA1537 for frame shift mutations. Each series of samples was disso1ved in tetrahydrofuran(inhibitor free) and tested at doses ranging from 0.05 to 5 mg/plate. The autoxidized soybean oil increased significantly(p<0.05) the number of $His^+$ revertant colonies in cases of TA 98 with S9 mix, TA100 without S9 mix, 1535 and 1537 with and without S9, respectively. The samples having the highest peroxide values showed the strongest mutagenicity. It seemed that the amount of hydroperoxides in the oils was closely related to the mutagenic activity of the respective oils.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.5
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• pp.717-724
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• 2020

Styela plicata are naturally-occurring marine resources easily found along the coastlines that have established their niche as functional food and nutraceuticals ingredient along with their increasing consumer demand. Ascidian contain a large amount of dietary fiber but only the meat has been utilized and consumed while the rest of its parts are discarded. Also, various studies have been conducted on the meat of ascidians while studies on the functionality of the ascidian tunics, which were mostly undervalued, were scarce. In this study, we investigated and explored the glycosaminoglycans (GAGs) contents in the tunics of S. plicata, and their potential use as functional ingredient in pharmaceutical and nutraceutical applications. Sulfated GAGs and uronic acids contents were 8.9-10.7 g/100 g and 9.4-11.3 g/100 g, respectively. Highest GAGs content was extracted with optimum Brix at 7-9. Extraction efficiency using hot water at 121℃ was 4.22% while enzyme extraction using Protamex was more efficient at 5.91%. GAGs extracted from S. plicata tunics exhibited collagenase inhibitory activity of 75.2% at 100 ㎍/mL and procollagen synthesis activity of 80.1% at 100 ㎍/mL.

• Water for future
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• v.20 no.2
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• pp.127-138
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• 1987

For determination of the design wave, a method of estimating the design wind speed at sea from the wind records at the nearby weather stations on land is proposed. Along the West Coast, the design wind speed are shown to have two main directions; namely, N through W, and WSW through S. Through the analysis of weather maps, fetches for the main wind directions along the West Coast are determined. The wind speeds at sea are found to have 0.8~0.9 times the wind speed at the stations on land for U$\geq$20m/s. The West Coast may be divided into three regions for which fetches are determind uniquely. Design waves with return period of 100 years are determined by the revised S.M..B. method along the West Coast, and show the deep water significant wave heights of 4.4~8.3 meters with wave periods of 8.9~12.0 seconds.

• Journal of the Korean institute of surface engineering
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• v.53 no.1
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• pp.9-14
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• 2020

CuS (copper sulfide) thin films having the same thickness of 100nm were deposited on the glass substrates using by radio frequency (RF) magnetron sputtering method. RF powers were applied as a process variable for the growth of CuS thin films. The structural and optical properties of CuS thin films deposited under different power conditions (40-100W) were studied. XRD analysis revealed that all CuS thin films had hexagonal crystal structure with the preferential growth of (110) planes. As the sputtering power increased, the relative intensity of the peak with respect to the (110) planes decreased. The peaks of the two bands (264cm^-1 and 474cm^-1) indicated in the Raman spectrum exactly matched the typical spectral values of the covellite (CuS). The size and shape of the grains constituting the surface of the CuS thin films deposited under the power condition ranging from 40W to 80W hardly changed. However, the spacing between crystal grains tended to increase in proportion to the increase in sputtering power. The maximum transmittance of CuS thin films grown at 40W to 80W ranged from 50 % to 51 % based on 580nm wavelength, and showed a relatively small decrease of 48% at 100W. The band gap energy of the CuS thin films decreased from 2.62eV (at 40W) to 2.56eV (at 100W) as the sputtering power increased.

• Journal of Korean Society for Atmospheric Environment
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• v.10 no.E
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• pp.325-331
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• 1994

Organic extracts of diesel- exhaust particulates were analyzed for mutagenicity using Ames Salmonella typhimurium assay system. An experimental diesel microbus used was drived on the chassis dynamometer according to CVS-75 mode. The samples were taken from the mixed gases in a dilution tunnel. With a high-volume air sampler equipped with double filter holders, particulate matters were collected on a teflon-coated glass fiber filter placed behind a activated carbon filter. After ultrasonic extraction with benzene- ethanol and evaporation to dryness, the residue was dissolved in dimethylsulfoxide. Each sample was tested toward 2 strains, TA100 and TA98 by the pre-incubation method in the absence and presence of S-9mix. Average concentration of diesel- exhaust particulates was about 116.6mg/m$^3$, and 44.1~62.2 ％ to the total weight of particulates, consisted of organic matters. The mutagenicities of diesel- exhaust particulate organic matters were 4,512 and 2,205 revertants/m$^3$ toward TA100 without and with S-9mix, respectively. Those toward TA98 were 13,367 and 3,715 revertants/m$^3$, respectively.

• Korean Journal of Veterinary Service
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• v.22 no.3
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• pp.221-237
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• 1999

To investigate the specificity of rapid slide agglutination test for pullorum-gallinarum diseases and to obtain a basic data for avian salmonellosis control, salmonella isolation was peformed for the layer chickens positively reacted in pullonlm-typhoid agglutination test. The biochemical, serological and antimicrobial properties of the isolates were examined. The results obtained through this study were summarized as follows; 1. Of 2,384 chickens tested by the agglutination test, 606 chickens (25.4%) were positive reactors. 154 of 606 reactors and 49 of the non-reacting chickens were investigated for salmonella isolation, resulting in isolation of 68 strains of salmonellae from 27 chickens. 2. By organs, the isolation frequency from liver, cecum, spleen, ovary and gall bladder showed 8.9% (18 strains), 8.9% (18 strains), 7.4% (15 strains), 4.4% (9 strains) and 3.9% (8 strains), respectively. 3. By culture medium the combination of selenite broth and MacConkey agar revealed the highest isolation rate and the enrichment culture by delayed secondary enrichment culture method was found the most effective for salmonella isolation. 4. The serotypes of 68 salmonella isolates were identified as 3 strains of S pullorum, 24 strains of S gallinarum, 15 strains of S typhimurium, 8 strains of S enteritidis, 7 strains of S paratyphi A, 5 strains of S typhimurium and 6 strains of the other salmonellae. 5. The serotypes of 8 salmonella strains isolated from 49 chickens non-reacting in pullorum-typhoid agglutination test were identified as 3 strains of S typhimurium and 5 strains of S infantis. 6. When 24 chickens of which 68 strains of salmonellae isolated were examined by microplate agglutination test, the average antibody titer for pullorum antigen was $2^{5.25}$. The chickens at antibody titer between $2^3$ and $2^5$ showed the higher frequency of isolation as compared with the chickens at the other titers. 7. When salmonella isolates were tested the antimicrobial drug sensitivity by disk diffusion method, S paratyphi A were highly sensitive by 100% to ATM and GM, S typhimurium, by 88% to AM, CIP, IMP and TN, S infantis, by 100% to AM, CRO, ENR and PIP, S enteritidis,by 100% to IMP and PIP, S pullorum, by 100% to ATM, CRO, ENR and PIP and S gallinarum, by 92% to CRO, CIP and PIP.

• Clinical and Experimental Emergency Medicine
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• v.5 no.4
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• pp.211-218
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• 2018

Objective This study aimed to determine whether simultaneous decreases in the serum levels of cell adhesion molecules (intracellular cell adhesion molecule-1 [ICAM-1], vascular cell adhesion molecule-1 [VCAM-1], and E-selectin) and S100 proteins within the first 24 hours after the return of spontaneous circulation were associated with good neurological outcomes in cardiac arrest survivors. Methods This retrospective observational study was based on prospectively collected data from a single emergency intensive care unit (ICU). Twenty-nine out-of-hospital cardiac arrest survivors who were admitted to the ICU for post-resuscitation care were enrolled. Blood samples were collected at 0 and 24 hours after ICU admission. According to the 6-month cerebral performance category (CPC) scale, the patients were divided into good (CPC 1 and 2, n=12) and poor (CPC 3 to 5, n=17) outcome groups. Results No difference was observed between the two groups in terms of the serum levels of ICAM-1, VCAM-1, E-selectin, and S100 at 0 and 24 hours. A simultaneous decrease in the serum levels of VCAM-1 and S100 as well as E-selectin and S100 was associated with good neurological outcomes. When other variables were adjusted, a simultaneous decrease in the serum levels of VCAM-1 and S100 was independently associated with good neurological outcomes (odds ratio, 9.285; 95% confidence interval, 1.073 to 80.318; P=0.043). Conclusion A simultaneous decrease in the serum levels of soluble VCAM-1 and S100 within the first 24 hours after the return of spontaneous circulation was associated with a good neurological outcome in out-of-hospital cardiac arrest survivors.