• Title/Summary/Keyword: Science Laboratory

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Synthesis, Stability Constants, X-ray Structure and Electrochemical Studies of Copper (II) 1, 14-Bis (2-hydroxybenzyl)-2, 6, 9, 12-tetraazatetradecane.tetrahydrochloride Complex (1, 14-Bis(2-hydroxybenzyl)-2, 6, 9, 12-tetraazatetradecane.tetrahydro-chloride 구리착물의 합성, 안정도상수, X-ray 구조 및 전기화학적 연구)

  • Kim, Sun-Deuk;Kim, Jun-Kwang;Kim, Seong-Yun
    • Analytical Science and Technology
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    • v.13 no.2
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    • pp.173-178
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    • 2000
  • A new open-chain ligand containing two phenol groups, 1, 14-Bis (2-hydroxybenzyl)-2, 6, 9, 12-tetraazatetradecane(bsated) was synthesized as its tetrahydrochloride salt and characterized by elemental analysis, mass, infrared and NMR. Its proton dissociation constants ($logK^n{_H}$) and stability constants ($logK_{ML}$) toward $Co^{2+}$, $Ni^{2+}$, $Cu^{2+}$ and $Zn^{2+}$ were determined at $25^{\circ}C$ and 0.10M($KNO_3$) ionic strength in aqueous solution by potentiometry. The X-ray structure of its copper (II) complex [Cu(bsated)]$(ClO_4)_2$ was reported: Monoclinic space group $P2_1/n$, $a=17.856(4){\AA}$, $b=17.709(1){\AA}$, $c=8.539(2){\AA}$, $V=2700(2){\AA}$ with Z=4. Electrochemical studies of [Cu(bsated)]$(ClO_4)_2$ complex in dimethyl sulfoxide (DMSO) solution containing tetrabutylammonium perchlorate (supporting electrolyte) were carried out by cyclic voltammograms (CV) and normal pulse voltammetry (NPV).

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A study on development of CRM by means of XRF analysis for fine ceramic ($BaTiO_3$) (티탄산바륨 소재의 XRF 분석용 CRM 개발에 관한 연구)

  • Kim, Young Man;Jeong, Chan Yee;Lim, Chang Ho;Song, Taek Yong;Lee, Dong Soo
    • Analytical Science and Technology
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    • v.9 no.4
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    • pp.382-391
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    • 1996
  • In this study, 12 different chemical species of fine ceramic($BaTiO_3$) were synthesized as the standard materials for the fast and accurate measurements of X-ray fluorescence spectrometry. Samples were diluted to sixteen times with the filling compound ($Li_2B_4O_7+LiBO_2$) in order to remove the matrix effect, and to get the convenient storage and homogeneity of ingredients. The matrix effects among the ingredients were corrected by the empirical coefficient method based on the Lucas-Tooth and Price model. The standard curve on 12 standard materials containing 15 elements were obtained by using X-ray fluorescence spectrometry at three different laboratories. The correlation factors of BaO, PbO, SrO, $Fe_2O_3$, $La_2O_3$, $SnO_2$, ZnO, $ZrO_2$, CaO indicated the relati vely good agreement over 0.995 among the three different laboratories. $SiO_2$ and $Al_2O_3$ showed the poor linearity because of their low fluorescence intensities.

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Gas chromatographic profiles of rose essential oils: a round-robin test on oil of rose, Chinese Kushui type (Rosa sertata × Rosa rugosa) (장미 정유의 기체 크로마토그래피 분석표: 중국산 쿠스이형 장미유에 대한 재현정밀도 시험)

  • Son, Hyun-Hwa;Lee, Dong-Sun
    • Analytical Science and Technology
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    • v.25 no.4
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    • pp.207-213
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    • 2012
  • Analysis of the aroma constituents present in the rose essential oil of Chinese Kushui type (Rosa sertata ${\times}$ Rosa rugosa) by GC-FID and GC-MS was performed independently as an expert for the inter-laboratory round-robin test to verify reproducibility according to the decision of the preliminary meeting of ISO/TC-54 (Shanghai, Sep. 14-15, 2010). Total 179 peaks (using SPB-1 apolar column), 165 peaks (using DB-624 intermediate polar column), and 162 peaks (using Supelcowax-10 polar column) were separated by GC-FID, respectively. Major constituents (over 5%) by GC-FID were ${\beta}$-citronellol (41.6~46.7%), geraniol (9.7~11.0%), and nerol (3.4~4.5%). ${\beta}$-Citronellol peak was overlapped with nerol peak on SPB-1 and DB-624 columns, whereas the two peaks were separated each other on Supelcowax-10 column. Our results were generally consistent with Chinese data (ISO/DIS 25175); however, a peak of phenethyl alcohol separated by using PEG (Supelco wax) column was found at the quite different retention time. Comparative analysis was conducted using Bulgarian rose (Rosa damascena Miller) oil and perfume. Bulgarian rose oil showed rich amounts of characteristic aroma constituents than the essential oil of Chinese Kushui type.

Long-term Trend Analysis of Key Criteria Air Pollutants over Air Quality Control Regions in South Korea using Observation Data and Air Quality Simulation (관측자료와 대기질 모사를 이용한 주요 기준성 대기오염물질의 권역별 장기변화 분석)

  • Ju, Hyeji;Kim, Hyun Cheol;Kim, Byeong-Uk;Ghim, Young Sung;Shin, Hye Jung;Kim, Soontae
    • Journal of Korean Society for Atmospheric Environment
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    • v.34 no.1
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    • pp.101-119
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    • 2018
  • In this study, we analyzed long-term measurements and air quality simulation results of four criteria air pollutants ($PM_{10}$, $O_3$, $NO_2$, and $SO_2$) for 10 years, from 2006 to 2015, with emphasis on trends of annual variabilities. With the observation data, we conducted spatial interpolation using the Kriging method to estimate spatial distribution of pollutant concentrations. We also performed air quality simulations using the CMAQ model to consider the nonlinearity of the secondary air pollutants such as $O_3$ and the influence of long-range transport. In addition, these simulations are used to deduce the effect of long-term meteorological variations on trends of air quality changes because we fixed the emissions inventory while changing meteorological inputs. The nation-wide inter-annual variability of modeled $PM_{10}$ concentrations was $-0.11{\mu}g/m^3/yr$, while that of observed concentrations was $-0.84{\mu}g/m^3/yr$. For the Seoul Metropolitan Area, the inter-annual variability of observed $PM_{10}$ concentrations was $-1.64{\mu}g/m^3/yr$ that is two times rapid improvement compared to other regions. On the other hand, the inter-annual variability of observed $O_3$ concentrations is 0.62 ppb/yr which is larger than the simulated result of 0.13 ppb/yr. Magnitudes of differences between the modeled and observed inter-annual variabilities indicated that decreasing trend of $PM_{10}$ and increasing trend of $O_3$ are more influenced by emissions and oxidation states than meteorological conditions. We also found similar patterns in $NO_2$. However, $NO_2$ trends showed greater regional and seasonal differences than other pollutants. The analytic approach used in this study can be applicable to estimate changes in factors determining air quality such as emissions, weather, and surrounding conditions over a long term. Then analysis results can be used as important data for air quality management planning and evaluation of the chronic impact of air quality.

Life Cycle and Breeding Information of Leptalina unicolor from Korea (Lepidoptera : Hesperiidae) (한국산 은줄팔랑나비(Leptalina unicolor : Hesperiidae)의 생활환과 사육정보)

  • Hong, Sung-Jin;Yoon, Chun-Sik;Kim, Hyoung-Gon;Cheong, Seon-Woo
    • Journal of Environmental Science International
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    • v.25 no.12
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    • pp.1633-1641
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    • 2016
  • Leptalina unicolor is a hesperiid butterfly with a restricted distribution in Korea, Japan, China, and Russia. Recently, the number of individuals is rapidly decreased in their natural habitat. This skipper has been classified as an endangered species in the 'Red Data Book', and according to an IUCN report, is under threat of extinction. Therefore, the conservation and restoration of this species both locally and globally are urgently needed. A population of L. unicolor was found in an unknown habitat in Jaeyaksan, Miryang, Gyeongsangnam-do, Korea in 2011, and these individuals were used in the present study. Here, the life cycle, characteristics of each instar larva and breeding information were determined by breeding L. unicolor in the laboratory from 2012 to 2015. The results indicated that L. unicolor occurs twice a year and over-winter as a fifth instar larva. A spring-form female individual laid $17.25{\pm}5.52eggs$, and summer form laid $29.00{\pm}5.86eggs$; it takes $53.79{\pm}0.73days$ for L. unicolor to develop from eggs to adults. After spawning, the eggs developed in $6.16{\pm}0.18days$, and larvae developed in $33.71{\pm}0.58days$; the pre-pupal stage to emergence required $14.22{\pm}0.31days$. Based on these results, we presented effective breeding information for the restoration and proliferation of the species. Several candidate plants species have been reported in the literature as a food source for L. unicolor, but we found that the preferred diet this butterfly was Miscanthus sinensis. The larvae could move easily when their preferred diet was planted in ${\geq}80%$ the cage floor area Year-round breeding was achieved by placing overwintering individuals in low temperatures in autumn. To our knowledge, this is the first study to the biology of L. unicolor in Korea, and the results of this study could be used as preliminary information for the conservation and restoration of this species in its natural habitat.

DEVELOPMENT OF A FLUXGATE MAGNETOMETER FOR THE KITSAT-3 SATELLITE (과학위성용 자력계 탑재체 개발에 관한 연구)

  • ;;;;;;Onishi Nobugito
    • Journal of Astronomy and Space Sciences
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    • v.14 no.2
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    • pp.312-319
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    • 1997
  • The magnetometer is one of the most important payloads for scientific satellite to monitor the near-earth space environment. The electromagnetic variations of the space environment can be observed with the electric and magnetic field measurements. In practice, it is well known that the measurement of magnetic fields needs less technical complexities than that of electric fields in space. Therefore the magnetometer has long been recognized as one of the basic payloads for the scientific satellites. In this paper, we discuss the scientific fluxgate magnetometer which will be on board the KITSAT-3. The main circuit design of the present magnetometer is based on that of KITSAT-1 and -2 but its facilities have been re-designed to improve the resolution to about 5nT for scientific purpose. The calibration and noise level test of this circuit have been performed at the laboratory of the Tierra Tecnica company in Japan.

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Foams for Aquifer Remediation: Two Flow Regimes and Its Implication to Diversion Process

  • Kam, Seung-Ihl;Jonggeun Choe
    • Journal of Soil and Groundwater Environment
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    • v.9 no.1
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    • pp.1-11
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    • 2004
  • Foam reduces the mobility of gas phase in porous media to overcome gravity override and to divert acid into desired layers in the petroleum industry and to enhance the efficiency of environmental remediation. Recent experimental studies on foam show that foam exhibits a remarkably different flow rheology depending on the flow regime. This study, for the first time, focuses on the issues of foam diversion process under the conditions relevant to groundwater remediation, combining results from laboratory linear-flow experiments and a simple numerical model with permeability contrasts. Linear flow tests performed at two different permeabilities (k = 9.1 and 30.4 darcy) confirmed that two flow regimes of steady-state strong foams were also observed within the permeability range of shallow geological formations. Foam exhibited a shear-thinning behavior in a low-quality regime and near Newtonian rheology in a high-quality regime. Data taken from linear flow tests were incorporated into a simple numerical model to evaluate the efficiency of foam diversion process in the presence of permeability contrasts. The simple model illustrated that foam in the high-quality regime exhibited a successful diversion but foam in the low-quality regime resulted in anti-diversion, implying that only foam in the high-quality regime would be applicable to the diversion process. Sensitivity study proved that the success of diversion process using foam in the high-quality regime was primarily controlled by the limiting capillary pressures (${P_c}{^*}$) of the two layers of interest. Limitations and implications are also discussed and included.

Bee-Venom Acupuncture Treatment of Hip Osteoarthritis in a Dog (개에서 둔부 골관절염의 봉침 치료)

  • Kim Tae-Hwa;Kim Byung-Young;Kim Won-Bae;Kim Kwang-Shik;Liu Jianzhu;Kim Duck-Hwan;Rogers Phil A.M.
    • Journal of Veterinary Clinics
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    • v.23 no.2
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    • pp.190-193
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    • 2006
  • Two weeks of therapy with intra-articular hyaluronic acid and oral caprofen failed to improve the clinical signs of hip osteoarthritis radiologically confirmed in a dog. Then, over the period of 30 days (7 sessions at 5-day intervals), bee- venom acupuncture (BV-AP, injection of bee venom at acupoints, also called apitoxin-aquapuncture) plus Trigger Point (TP) therapy was used. Five acupoints on the affected right limb were injected each time: GB30(as local point), plus ST35, GB33, BL40 and LIV08 (as distant points). The injection mixture (0.2 ml/point; total 1 ml/session) was saline + apitoxin + 2% lidocaine, so that the injected solution contained $100{\mu}g$ apitoxin diluted in 0.2% lidocaine-saline solution/ml. The total dose of apitoxin used was, therefore, $100{\mu}g/session$, divided over the 5 acupoints. One TP in the middle of the right quadriceps muscle was injected with 2% lidocaine (0.2 ml/point) each time. BV-AP improved the clinical signs rapidly; lameness and ataxia were disappear after 7 sessions (30 days); the right hind limb muscular atrophy was much improved and the hip radiograph was almost normal two weeks after 7 sessions (44 days). The present patient was a case with canine hip osteoarthritis which showed favorable therapeutic response by BV-AP plus TP therapy.

Anti-Obesity Activity, Anti-Cancer Activity and Single Oral Dose Toxicity of Inonotus xeranticus Extracts (기와층버섯 추출물의 항비만활성, 항암활성 및 단회경구독성시험)

  • Kang, Eun-Hee;Lee, In-Kyoung;Hwang, Mi-Hyun;Choi, Jae-Young;Chang, Zhi-Qiang;Rhee, Man-Hee;Yun, Bong-Sik;Jiang, Cheng-Zhe;Kim, Kil-Soo;Park, Seung-Chun
    • Toxicological Research
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    • v.23 no.3
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    • pp.253-261
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    • 2007
  • In this study, we investigated the in vitro anti-obesity, anti-cancer activity and single oral dose toxicity of Inonotus xeranticus extracted by methanol (INXM) or ethyl acetate (INXE). In order to investigate anti-obestity effect of Inonotus xeranticus extracts, the 3T3-L1 cells were treated with these extracts at various concentrations(1, 10, 100 and $300{\mu}g/ml$). It was observed that 3T3-L1 cells treated with $100{\mu}g/ml$ of Inonotus obliquus ethyl acetate extract (INOE), INXM and INXE, in the absence of differentiation cocktail (0.5mM isobutylmethylxanthine (IBMX) $1{\mu}M$ dexamethasone, $1{\mu}M$ insulin), differentiated at a rate of 78.5, 80.9, and 76.4% respectively. Differentiation rates of 86.6% and 83.4% were observed in 3T3-L1 cells which were treated with differentiation cocktail at $100{\mu}g/ml$ of INXM and INXE, respectively. The anti-cancer effect of Inonotus xeranticus extracts was investigated using a method of sulforhodamine B in sarcoma 180 cell line. The cells were treated with these extracts (1, 10, 100 and $300{\mu}g/ml$) for 48 hours. The growth of cells which were treated with $300{\mu}g/ml$ of INXM was inhibited by 80.1%. The growth of sarcoma 180 cells which were treated with 100 and $300{\mu}g/ml$ of INXE was inhibited by 74.7% and 64.5%, respectively. In single oral dose toxicity study, no differences were observed between control and treated groups in clinical signs, body weight gains, and feed and water consumptions. The results indicated that Inonotus xeranticus extracts did not show any toxic effects at 2,000mg/kg in mice, and the $LD_{50}$ of these extracts was found to be higher than 2,000 mg/kg in this experiment. From the above results, Inonotus xeranticus methanol and ethyl acetate extracts might have useful clinical applications in the management of cancer and obesity and may also be useful as a medicinal food.

Seroprevalence of Plasmodium vivax in the Republic of Korea (2003-2005) using Indirect Fluorescent Antibody Test

  • Kim, Tong-Soo;Kang, Yoon-Joong;Lee, Won-Ja;Na, Byoung-Kuk;Moon, Sung-Ung;Cha, Seok Ho;Lee, Sung-Keun;Park, Yun-Kyu;Pak, Jhang-Ho;Cho, Pyo Yun;Sohn, Youngjoo;Lee, Hyeong-Woo
    • Parasites, Hosts and Diseases
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    • v.52 no.1
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    • pp.1-7
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    • 2014
  • Plasmodium vivax reemerged in the Republic of Korea (ROK) in 1993, and is likely to continue to affect public health. The purpose of this study was to measure levels of anti-P. vivax antibodies using indirect fluorescent antibody test (IFAT) in border areas of ROK, to determine the seroprevalence of malaria (2003-2005) and to plan effective control strategies. Blood samples of the inhabitants in Gimpo-si, Paju-si, and Yeoncheon-gun (Gyeonggi-do), and Cheorwon-gun (Gangwon-do) were collected and kept in Korea Centers for Disease Control and Prevention (KCDC). Out of a total of 1,774 serum samples tested, the overall seropositivity was 0.94% (n=17). The seropositivity was the highest in Paju-si (1.9%, 7/372), followed by Gimpo-si (1.4%, 6/425), Yeoncheon-gun (0.67%, 3/451), and Cheorwon-gun (0.19%, 1/526). The annual parasite incidence (API) in these areas gradually decreased from 2003 to 2005 (1.69, 1.09, and 0.80 in 2003, 2004, and 2005, respectively). The highest API was found in Yeoncheon-gun, followed by Cheorwon-gun, Paju-si, and Gimpo-si. The API ranking in these areas did not change over the 3 years. The seropositivity of Gimpo-si showed a strong linear relationship with the API of 2005 (r=0.9983, P=0.036). Seropositivity data obtained using IFAT may be useful for understanding malaria prevalence of relevant years, predicting future transmission of malaria, and for establishing and evaluating malaria control programs in affected areas.