• Title/Summary/Keyword: Pure sciences

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Estimate of Surface Ozone Concentration on Sunny Summer Days in Seoul Area by the Photochemical-Trajectory Model (광화학-궤적 모델에 의한 여름철 맑은 날 서울지방의 지상 오존 농도 추정)

  • 이시우;이광목
    • Journal of Environmental Science International
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    • v.11 no.6
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    • pp.497-506
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    • 2002
  • A Photochemical-Trajectory model was used to understand the production of ozone in the atmospheric boundary layer. This model was composed of the trajectory and the photochemical models. To calculate trajectories of air parcels, winds were obtained from the three-dimensional nonhydrostatic mesoscale model (PSU/NCAR MM5V2), and the results were interpolated into constant height surfaces. Numerical integration in the trajectory model was performed by the Runge-Kutta method. The photochemical model consisted of chemical reactions and photodissociation processes. Chemical equations were integrated by the semi-implicit Bulirsch-Stoer method. We performed our experiments from 21 July to 23 July 1994 during the summer time for Seoul area. During the time of maximum ozone concentration in Seoul, four trajectories of air parcels which traveled from Inchon to Seoul were selected. Ozone concentrations estimated by two models are compared with observed one in Seoul area and the photochemical-trajectory model is better fitted than pure photochemical model. During the selected period, high ozone concentrations in Seoul area were more influenced by transferred pollutants from Inchon than emitted pollutants in Seoul.

Identification and Characteristics of a Purple, Non-Sulfur Bacterium, Rhodobacter sp. EGH-24 from Korea Coast (한국 해안으로부터 Purple, Non-Sulfur Photosynthetic Bacterium, Rhodobacter sp. EGH-24의 분리 및 특성)

  • 차미선;김기한;조순자;이나은;이정은;이재동;박재림;이상준
    • Journal of Environmental Science International
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    • v.12 no.12
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    • pp.1293-1301
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    • 2003
  • A species of facultative photo-organotrophic, purple, non-sulfur bacterium was isolated from the 47 point at west and south coast of Korea in September 2001. Separated 13 samples of changes with red color under 28-32$^{\circ}C$, 3000 lux, anaerobe conditions for 7 days cultivated in basal medium. For pure isolation from 13 samples, we used agar-shake tube method (0.4 % agar) and separated 5 strains through 13-repetition test. EGH-24 and EGH-30 was identified as the same strain through the RAPD(Random Amplified Polymorphic DNA)-PCR of strain EGH-9, EGH-13, EGH-23, EGH-24, EGH-30. Four isolates cultivated in synthesis wastewater for wastewater biodegradation test. EGH-24 was selected with efficient wastwater treating strain. Based on the results obtained from morphology, nutrient requirements, major bacteriochlorophyll content, 16S-rDNA phylogenetic analysis, EGH-24 strain may be identified as a new strain of the genus Rhodobacter and named Rhodobacter sp. EGH-24.

APPELL'S FUNCTION F1 AND EXTON'S TRIPLE HYPERGEOMETRIC FUNCTION X9

  • Choi, Junesang;Rathie, Arjun K.
    • The Pure and Applied Mathematics
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    • v.20 no.1
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    • pp.37-50
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    • 2013
  • In the theory of hypergeometric functions of one or several variables, a remarkable amount of mathematicians's concern has been given to develop their transformation formulas and summation identities. Here we aim at presenting explicit expressions (in a single form) of the following weighted Appell's function $F_1$: $$(1+2x)^{-a}(1+2z)^{-b}F_1\;\(c,\;a,\;b;\;2c+j;\;\frac{4x}{1+2x},\;\frac{4z}{1+2z}\)\;(j=0,\;{\pm}1,\;{\ldots},\;{\pm}5)$$ in terms of Exton's triple hypergeometric $X_9$. The results are derived with the help of generalizations of Kummer's second theorem very recently provided by Kim et al. A large number of very interesting special cases including Exton's result are also given.

Analysis of Gases in Nuclear Fuel Rod by Quadrupole Mass Spectrometry (Quadrupole Mass Spectrometry를 이용한 핵연료봉내 기체분석)

  • Kim, Seung-Soo;Kang, Moon-Ja;Park, Soon-Dal;Park, Yong-Joon;Joe, Kih-Soo
    • Analytical Science and Technology
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    • v.12 no.2
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    • pp.94-98
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    • 1999
  • An analysis method of components and isotopic compositions of low pressure gases from nuclear fuel rod using quadrupole mass spectrometer was studied. The calibration curves of each gas in pure and mixtures of He, $N_2$, $O_2$, Ar, Kr and Xe were obtained as a function of pressure and concentration, respectively. Effect of molecular leak, located between sample chamber and analyser chamber, on the sensitivites was also studied. The results suggested that samples could be analysed accurately at the same analytical condition as that of synthetic gas mixture. The difference of sensitivities among isotopes of Kr and Xe was not observed in the range of measured pressure.

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Effects of the New Method of Computing Percentage of Victories on 2009~2010 Korea Professional Baseball and Suggestion of Complementary Measures (새로운 승률 계산 방식이 2009년과 2010년의 한국프로야구에 미친 영향 및 보완할 점)

  • Kim, Hyuk-Joo;Lee, Hyun-Jeong
    • The Korean Journal of Applied Statistics
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    • v.24 no.1
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    • pp.169-175
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    • 2011
  • Since 2009, a new method of computing the percentage of victories is being used in the regular league of the Korean professional baseball. This method produced enormous results from the first year of application, and also had an effect on the team standings in 2010. In this paper, we have examined the effects this method had on the Korean professional baseball in 2009 and 2010. We also have discussed what the Korea Baseball Organization need to complement in using this method and suggested complementary measures.

Preparation and characterization of ibuprofen-loaded alginate microspheres using ethylenediamine as a crosslinker

  • Maiti, Sabyasachi;Sa, Biswanath
    • Advances in Traditional Medicine
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    • v.8 no.2
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    • pp.178-186
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    • 2008
  • In this study, ionotropic gelation method was used for the preparation of ibuprofen-loaded calcium alginate (CALG) and ethylenediamine (EDA) treated calcium alginate (EDA-CALG) microspheres. The effect of EDA-treatment on drug entrapment efficiency, particle size, morphology, swelling behavior and in vitro release characteristics of the microspheres was investigated by varying its concentration from 0.5 to 2% (v/v). The reduction in drug entrapment efficiency by a maximum of 44.60% was noted for EDA-CALG microspheres compared to untreated CALG microspheres. The particle size and swelling index of EDA-CALG microspheres were reduced with increasing EDA concentration. All the microspheres were observed to retain their spherical shapes with rough surfaces. EDA-CALG microspheres prepared using 1% and 2% v/v EDA, released almost all of its content within 7 h in pH 6.8 phosphate buffer, however, CALG microspheres were found to release the same within 3 h. The intensity of melting endothermic peak of ibuprofen reduced significantly at lower drug load as experienced from DSC thermograms. The FT-IR spectrum of pure ibuprofen, ibuprofen-loaded CALG and EDA-CALG microspheres showed the characteristic band of C = O stretching vibration of ibuprofen. Hence, this study revealed that EDA can be employed for the preparation of ibuprofen-loaded CALG microspheres to retard the drug release to some extent.

Zinc Accumulation in the Cell of Zinc-Tolerant Bacteria, Pseudomonas chlororaphis, and Recovery of Zinc from the Cells Accumulating Zinc (아연 내성균의 균체내 아연 축적특성 및 균체내 축적된 아연의 회수)

  • 조주식;한문규
    • Journal of Environmental Science International
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    • v.5 no.3
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    • pp.317-327
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    • 1996
  • This study was performed to develop the biological treatment technology of wastewater polluted with heavy metals. Zinc-tolerant microorganism, such as Pseudomonas chlororaphis which possessed the ability to accumulate zinc, was isolated from industrial wastewaters polluted with various heavy metals. The characteristics of zinc accumulation in the cells, recovery of the zinc from the cells accumulating zinc, were investigated. Removal rate of zinc from the solution containing 100 mall of Zinc by zinc-tolerant microorganism was more than 90% at 48 hours after inoiulation of the microorganisms. A large number of the electron-dense granules were found mainly on thIn cell wall and membrane fractions, when determined by transmission electron microscope. Energy dispersive X- ray spectroscopy revealed that the electron-dense granules were zinc complex with the substances binding Heavy metals. The zinc accumulated into cells was not desorbed by distilled water, but more than 80% of the zinc accumulated was desorbed by 0.1M-EDTA. The residues of the cells after combustion at 55$0^{\circ}C$ amounted to about 21% of the dry weight of the cells. EDS analysis showed that the residues were comparatively pure zinc compounds containing more than 79% of zinc.

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A Study on the Treatment of Phenol Wastewater in an Anaerobic Fluidized-Bed Reactor (혐기성 유동층 반응기에서 페놀 폐수 처리에 관한 연구)

  • 박동일;안재동;신승훈;장인용
    • Journal of Environmental Health Sciences
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    • v.22 no.2
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    • pp.96-103
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    • 1996
  • The objectives of this study were to examine the biodegradation of phenol using the anaerobic fluidized bed reactor(AFBR). Mixed microorganisms were selected from the anaerobic digestion tank, and could be adapted to high concentration of phenol by increasing the phenol concentration 600-3600 mg/l step by step. The results were summarized as follows: 1. The average removal efficiency of phenol was 90%, decreased by increasing concentration of phenol, and then a shock range was 1200~2400 ppm. 2. The production rate of biogas in overall limits was proportional to the concentration of influent phenol. 3. At steady state, compositions of gases were $CH_4$ 55~60%, $C0_2$ 34~43%, respectively. These were similar to that of the theoretical estimates. 4. The production rates of biogas and methane per the molarity of phenol removed were linearly increased, 56.45 l gas/mol-phenol and 29.20 l $CH_4/mol$-phenol. Using this biogas, the recoverable energy was 269.1 kcal/mol phenol. It was 120.2 kcal/g-COD, transforming into the chemical oxygen demand. 5. The bulk of microorganisms existed in suspended section of fluidized bed with type of biofilm and its concentration was 340 mg/g-media. In conclusion, the anaerobic treatment of pure phenol was possible and its removal efficiency, introducing the AFBR, was successful. Also toxic organic compound such as phenol was biodegradable and was recoverable as resource of energy.

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Removal of Copper ton by Na-P1 Synthesized from Jeju scoria (제주 스코리아로부터 합성된 Na-P1 제올라이트에 의한 Cu 이온 제거)

  • 감상규;홍정연;현성수;안병준;이민규
    • Journal of Environmental Science International
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    • v.11 no.1
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    • pp.75-83
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    • 2002
  • The removal performance of copper ion was studied using Na-P1 zeolites synthesized from Jeju scoria. The scoria which is found in large amounts in Jeju Island, was sampled at four regions, Jeju-shi Bonggae-dong(A). Pukcheju-gun Hanlim-eup Sangmyong-ri Mangoreum(B), Pukcheju-gun Hanlim-eup Keumag-ri(C) and Namcheju-gun Andeok-myun Dongkwang-ri(D). Synthetic Na-P1 zeolites used in this study were more effective than natural zeolite and scoria for the removal of copper ion. The removal performances of copper ion decreased in the order of Na-P1(D) > Na-P1(C) > Na-P1(B) > Na-P1(A) among Na-P1 synthesized from the scoria according to region. These results showed the same trend with cation exchange capacity(CEC) for each synthetic zeolite, i.e., the synthetic Na-P1 zeolite with a higher CEC showed a higher removal performance. The effective diffusion coefficients of copper ion by synthetic Na-P1 zeolites were one hundred and ten times higher than those by a pure zeolite 4A and the zeolite A synthesized from coal fly ash, respectively.

An Experimental Study on Bacterial Adhesion onto Activated Carbon and Ceramic (활성탄 및 세라믹 재질에의 세균 부착성에 대한 연구)

  • Kwon Sung-Hyun;Cho Dae-Chul;Rhee In-Hyoung
    • Journal of Environmental Science International
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    • v.14 no.12
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    • pp.1163-1170
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    • 2005
  • The microbial adsorption characteristics of two different media for biological treatment were studied using attached diverse microbes onto activated carbon and ceramic. The results in the experiments of the characteristics of physical adhesion on two different media with addition of high and low concentrated substrate in the culture were observed that the efficient of adhesion onto F-400 activated carbon was higher over that of ceramic due to the surface area of media. The irradiation treatment by ultrasonication with 400 W power and 3 min retention time on the media without addition substrate conditions and subsequent mixing throughly the culture showed the highest efficiency of cell detachment on the media. Three different microbes, P. ovalis, A calcoaceticus, and B. subtillis were used for the study of the characteristics of microbial adhesion on the media. p ovalis showed the highest adhesion capability while B. subtillis showed the lowest capability adhesion onto media either addition of substrate in the culture. The mixed bacterial culture showed $10\%$ lower removal efficiency of DOC in the low concentrated substrate culture compared to the single pure culture. Whileas, it did not show significant difference between two cultures at high concentrated substrate. It was also observed same population density of microorganism by counting of microbes adhered to microbial media with an ultrasound treatment.