• Title/Summary/Keyword: Secondary sources

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CCD PHOTOMETRY OF STANDARD STARS AT MAIDANAK ASTRONOMICAL OBSERVATORY IN UZBEKSTAN: TRANSFORMATIONS AND COMPARISONS

  • Lim, Beomdu;Sung, Hwan-Kyung;Bessell, M.S.;Karimov, R.;Ibrahimov, M.
    • Journal of The Korean Astronomical Society
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    • v.42 no.6
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    • pp.161-174
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    • 2009
  • Observation of standard stars is of crucial importance in stellar photometry. We have studied the standard transformation relations of the UBV RI CCD photometric system at the Maidanak Astronomical Observatory in Uzbekistan. All observations were made with the AZT-22 1.5m telescope, SITe 2k CCD or Fairchild 486 CCD, and standard Bessell UBV RI filters from 2003 August to 2007 September. We observed many standard stars around the celestial equator observed by SAAO astronomers. The atmospheric extinction coefficients, photometric zero points, and time variation of photometric zero points of each night were determined. Secondary extinction coefficients and photometric zero points were very stable, while primary extinction coefficients showed a distinct seasonal variation. We also determined the transformation coefficients for each filter. For B, V, R, and I filters, the transformation to the SAAO standard system could be achieved with a straight line or a combination of two straight lines. However, in the case of the U filter and Fairchild 486 CCD combination, a significant non-linear correction term - related to the size of Balmer jump or the strength of the Balmer lines - of up to 0:08 mags was required. We found that our data matched well the SAAO photometry in V, B - V, V - I, and R - I. But in U - B, the difference in zero point was about 3.6 mmag and the scatter was about 0.02 mag. We attribute the relatively large scatter in U -B to the larger error in U of the SAAO photometry. We confirm the mostly small differences between the SAAO standard UBV RI system and the Landolt standard system. We also attempted to interpret the seasonal variation of the atmospheric extinction coefficients in the context of scattering sources in the earth's atmosphere.

Recovery of Palladium from a Mixture of Pt, Pd and Rh by Solvent Extraction

  • Kim, berly S. Svalstad;Kim, Nam-Soo;Kenneth N. Han
    • Proceedings of the IEEK Conference
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    • 2001.10a
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    • pp.482-488
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    • 2001
  • Platinum group metals (pgm) are useful to many industries such as chemical, dental and medical, petroleum, refining, electrical and electronic, and automotive. Researchers at the South Dakota School of Mines and Technology and PGM Recovery Ltd. have developed jointly an environmentally sound and metallurgically efficient process for extracting these metals from secondary sources. Once these metals have been dissolved in the leach liquor, the individual metals mainly platinum, palladium, and rhodium, should be separated in order to recover the individual metals with high purity. During this investigation, solvent extraction has been chosen as the method used to achieve the separation and extraction of platinum, palladium, and rhodium from the leach liquor. There were three solutions used throughout this procedure: 1) Synthetic solution (200 ppm Pt 80 ppm Pd 20 ppm Rh; 300 ppm Pt, 180 ppm Pd 50 ppm Rh), and 2) Auto catalyst leach liquors (100 ppm Pt, 30 ppm Pd, 20 ppm Rh). The solvents investigated included Lix 84(2-hydroxy-5-nonylacetonphenone oxime in a mixture with 5-dodecylsalicyloxime), Lix 84-I, ACORGA CLX-50 (diester of pyridine 3,5 dicarboxylic acid), and di-hexyl sulfide. The extraction values achieved using ACORGA CLX-50, Lix 84, and Lix 84-I were respectively Pt (25%, 0% 0%), Pd (100%, 99.8%, 95.3%), and Rh (99.1%, 35.5%, 4.25%). The stripping processes for the Lix 84, and Lix 84-I were proven to be more involved than others. The solutions were required to be simultaneously heated and stirred. The percentages acquired through these processes yielded unsatisfactory results. The stripping procedure for the ACORGA CLX-50 was easier to execute, yet the percentage recovered from this process was also unsatisfactory. Overall the di-hexyl sulfide has proved to be the most successful organic for this procedure. The average percent extracted for palladium was excellent with 99.9% - 100% with very little Platinum and rhodium extracted. The ability of stripping palladium in ammonia solution was also found to be excellent.

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An Assessment of the Usage of the Lagos Mass Transit Trains

  • Oni, S.I.;Okanlawon, K.R.
    • International Journal of Railway
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    • v.5 no.1
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    • pp.29-37
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    • 2012
  • The rail sector, despite its potential for curtailing the present chaotic transport situation in Lagos, remains inefficient and underutilized. In spite of past initiatives and the current attempt by the Lagos State Government to provide a mass transit rail service in Lagos, the share of rail mode in the transport sector has not been encouraging and the railway plays an insignificant role in urban mass transit in Lagos at present. This paper sets out to assess the usage of the Lagos mass transit trains. Hence, the paper determines the passenger traffic flow along the rail route in Lagos and the number of passengers carried between 2000 and 2009 by the Lagos Mass Transit Trains (LMTT) with a view to assessing the usage of the present LMTT. This paper also discusses the historical development of Nigerian railway and describes rail transport in Lagos. Data were obtained through secondary sources coupled with review of literature. The result of this study shows that for a period of 10 years (2000-2009), Lagos mass transit trains carried a total of 9,870,101 passengers, which gives an average of 987,010 passengers annually. This suggests that the service of the Lagos mass transit train is grossly underutilized. However, LMTT contributes enormously to NRC by carrying 68.5% of the total passenger traffic of NRC between 2000 and 2009. In terms of passenger traffic flow along the route of LMTT, for a period of 1 year, Agbado station recorded the largest number of passengers (393,811), followed by Ijoko (163,652) and Iddo (120,787), while Iganmu station has the lowest number of rail commuters (16,919). This study also discloses that the major commodities hauled by Lagos district of NRC from Lagos to the northern parts of the country in 2007 are Cars, Cement, Billet and Wheat.

Electrochemical Properties of 0.3Li2MnO3·0.7LiMn0.55Ni0.30Co0.15O2 Electrode Containing VGCF for Lithium Ion Battery

  • Kim, Jeong-Min;Jeong, Minchan;Jin, Bong-Soo;Kim, Hyun-Soo
    • Journal of Electrochemical Science and Technology
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    • v.5 no.1
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    • pp.32-36
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    • 2014
  • The $0.3Li_2MnO_3{\cdot}0.7LiMn_{0.55}Ni_{0.30}Co_{0.15}O_2$ cathode material was prepared via a co-precipitation method. The vapor grown carbon fiber (VGCF) was used as a conductive material and its effects on electrochemical properties of the $0.3Li_2MnO_3{\cdot}0.7LiMn_{0.55}Ni_{0.30}Co_{0.15}O_2$ cathode material were investigated. From the XRD pattern, the typical complex layered structure was confirmed and a solid solution between $Li_2MnO_3$ and $LiMO_2$ (M = Ni, Co and Mn) was formed without any secondary phases. The VGCF was properly distributed between cathode materials and conductive sources by a FE-SEM. In voltage profiles, the electrode with VGCF showed higher discharge capacity than the pristine electrode. At a 5C rate, 146 mAh/g was obtained compared with 232 mAh/g at initial discharge in the electrode with VGCF. Furthermore, the impedance of the electrode with VGCF did not changed much around $9-10{\Omega}$ while the pristine electrode increased from 21.5${\Omega}$ to $46.3{\Omega}$ after the $30^{th}$ charge/discharge cycling.

A Study on the Source Apportionment of the Atmospheric Fine Particles in Jeju area (제주지역 미세먼지의 오염원 규명에 관한 연구)

  • Hu, Chul-Goo;Yang, Su-Mi;Lee, Ki-Ho
    • Journal of Environmental Science International
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    • v.12 no.2
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    • pp.217-225
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    • 2003
  • Samples of size-fractionated PM10 (airborne particulate matter with aerodynamic diameter less than $10\mu\textrm{m}$) were collected at an urban site in Jeju city from May to September 2002. The mass concentration and chemical composition of the samples were measured. The data sets were then applied to the CMB receptor model to estimate the source contribution of PM10 in Jeju area. The average PM10 mass concentration was 28.80$\mu\textrm{g}/m^3$ ($24.6~33.49\mu\textrm{g}/m^3$), and the FP (fine particle with aerodynamic diameter less than $2.l\mu\textrm{m}$ fraction in PM10 was approximately 8% higher than the CP (coarse particle with aerodynamic diameter greater than $2.l\mu\textrm{m}$ and less than $10\mu\textrm{m}$ fraction in PM10. The CP composition was obviously different from the FP composition, that is, the most abundant water soluble species was nitrate ion in the FP, but sulfate ion in the CP. Also sulfur was the most dominant element in the FP, however, sodium was that in the CP. From CMB receptor model results, it was found that road dust was the largest contributor to the CP mass concentration (45% of the CP) and ammonium nitrate, domestic boiler, and marine aerosol were major sources to the CP mass. However, the secondary aerosol was the most significant contributor to the FP mass concentration (45% of the FP). In this study, it was suggested that the contributions of soil dust and gasoline vehicle became very low due to collinearity with road dust and diesel vehicle, respectively.

Rare earths from secondary sources: profitability study

  • Innocenzi, Valentina;De Michelis, Ida;Ferella, Francesco;Veglio, Francesco
    • Advances in environmental research
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    • v.5 no.2
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    • pp.125-140
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    • 2016
  • The paper is focused on the economic analysis of two hydrometallurgical processes for recovery of yttrium and other rare earth elements (REEs) from fluorescent phosphors of spent lamps. The first process includes leaching with sulphuric acid and precipitation of a mixture of oxalates by oxalic acid, the second one includes leaching with sulphuric acid, solvent extraction with D2EHPA, stripping by acid and recovery of yttrium and traces of other rare earths (REs) by precipitation with oxalic acid. In both cases the REEs were recovered as oxides by calcination of the oxalate salts. The economic analysis was estimated considering the real capacity of the HydroWEEE mobile's plant ($420kg\;batch^{-1}$). For the first flow-sheet the cost of recycling comes to $4.0{\euro}kg^{-1}$, while the revenue from the end-product is around $5.40{\euro}kg^{-1}$. The second process is not profitable, as well as the first one, taking into account the composition of the final oxides: the cost of recycling comes to $5.2{\euro}kg^{-1}$, while the revenue from the end-product is around $3.56{\euro}kg^{-1}$. The process becomes profitable if the final RE oxide mixture is sold for nearly $50{\euro}kg^{-1}$, a value rather far from the current market prices but not so unlikely since could be achieved in the incoming years, considering the significant fluctuations of the Res' market.

Prevalence and Risk Factors for Infection by Opisthorchis viverrini in an Urban Area of Mahasarakham Province, Northeast Thailand

  • Chaiputcha, Kusumaporn;Promthet, Supannee;Bradshaw, Peter
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.10
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    • pp.4173-4176
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    • 2015
  • The aim of this cross-sectional analytic study was to investigate the prevalence and risk factors for Opisthorchis viverrini (OV) infection in an urban area of Northeastern Thailand. The participants were 254 household representatives aged 15 years or older living in the most urbanised part of Chiang Yuen municipality in Mahasarakham Province. All participants provided stool samples which were examined using the modified Kato-Katz procedure, and a structured interview questionnaire was used to collection demographic information, knowledge about OV infection, and the consumption of unsafely prepared freshwater fish. The data were analyzed using descriptive statistics and logistic regression. The overall prevalence of OV infection was 15.0%, and in the multivariate analysis male gender was found to be significantly and positively associated with OV infection ($OR_{adj}=9.75$, 95%CI: 34.03-23.58) while education to secondary school level or above was a significant protective factor ($OR_{adj}=0.30$, 95%CI: 0.12-0.74). The eating of unsafely prepared fish and knowledge about OV were not significantly related to infection status. The findings were discussed in terms of issues for future research, especially the need to consider the possibility of higher rates of OV infection in urban areas than might be expected and to investigate the sources of infected fish products which may well be different from those in rural villages.

A Research on the Exchange of Costume Culture between Netherlands and Japan through 17-18 Century Dutch East India Company (17~18세기 동인도회사를 통한 네덜란드와 일본의 복식문화교류 연구)

  • Kim, Myung-Eun;Bae, Soo-Jeong
    • Journal of the Korean Society of Costume
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    • v.65 no.4
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    • pp.109-123
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    • 2015
  • The object of this research is to take a bilateral look into cultural exchanges of the Netherlands and Japan through the East India Company and thereby improve the general understanding in regards to the exchanges of costume cultures between the East and the West. The study conducted qualitative analyses on features of contemporary costumes of the Netherlands and Japan from 1602 to 1799 by investigating the secondary sources, such as the histories of costumes, arts, and literature. The results are as follows; the traditional sleeves of the Japanese Kimono were basically cut out in a straight line. However due to the growing popularity of the kimono home gown in Europe, the producers of the kimono in India as well as several other European countries modified them into western-style sleeves. Regarding the costumes of the Netherlands, which were introduced to Japan, the study found that Japan imported Dutch fabrics, instead of specific clothing items. In Japan, costume controls and anti-conspicuous consumption regulations among social classes including a closed-door policy had negative effects on both developments and exchanges of costumes of the country. However, when it comes to the Jinbaori, a costume for ruling classes, Japan was open to using fabrics, patterns and designs of the West. In light of what have been discussed so far, the study confirmed that the costume exchanges between the two countries started long after their first business of the general cultural exchanges. Though it is clear that the advancements in the natural sciences that the Japanese made can be attributed to the West, Japan was one of the nations that impacted the costume cultures in Europe.

Mass Cultivation and Secondary Metabolite Analysis of Rhodobacter capsulatus PS-2 (광합성세균 Rhodobater capsulatus PS-2의 대량배양 최적화 및 대사산물 분석)

  • Bong, Ki Moon;Kim, Jong Min;Yoo, Jae-Hong;Park, In Chul;Lee, Chul Won;Kim, Pyoung Il
    • KSBB Journal
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    • v.31 no.3
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    • pp.158-164
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    • 2016
  • Plant growth promoting (PGP) hormones, which are produced in a small quantity by bacteria, affect in plant growth and development. PGPs play an important role on the crop productivity in agricultural field. In this study, a photosynthetic bacterial strain producing the PGP was isolated from paddy soil. Bacterial isolate was gram negative, rod-shaped and motility positive. From the 16s rRNA gene sequence analysis, the isolate was identified as Rhodobacter capsulatus PS-2. The mass cultivation of R. capsulatus PS-2 was optimized by considering of the carbon, nitrogen and inorganic salt sources. Optimal medium composition was determined as Na-succinate 4.5 g, yeast extract 5 g, $K_2HPO_4$ 1 g, $MgSO_4$ 5 g, per liter. From the result of 500 L fermentation for 2 days using the optimal medium, the viable cells were $8.7{\times}10^9cfu/mL$. R. capsulatus PS-2 strain produced the carotenoid and indole-3-acetic acid (IAA). The carotenoid extraction and quantitative analysis were performed by HCl-assisting method. Total carotenoid contents from R. capsulatus PS-2 culture broth were measured as $7.02{\pm}0.04$ and $6.93{\pm}0.05mg/L$ under photoheterotrophic and chemoheterotrophic conditions, respectively. To measure the productivity of IAA, colorimetric method was employed using Salkowski reagent at optical density 535 nm. The results showed that the highest content of IAA was $197.44{\pm}5.92mg/L$ in the optimal medium supplemented with 0.3% tryptophan.

Is the Korean Duty Free Shop Industry Monopolistic? (한국 면세점 산업의 구조, 독과점인가?)

  • Lee, Hee-Tae;Cha, Moon-Kyung
    • Journal of Distribution Science
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    • v.14 no.10
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    • pp.47-57
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    • 2016
  • Purpose - This study's purpose is to investigate the market structure of the Korean duty free shop industry that has received recent attention from researchers and practitioners. By raising the question of whether or not the Korean duty free shop industry is unequivocally monopolistic, a wider viewpoint is provided. The study seeks to offer insights and managerial implications for marketers and policy makers who are in charge of regulating major Korean duty free shops. Research design, data, and methodology - The authors use secondary data from various sources, including Korea Customs Service and the Moodie Report, to investigate the structure of the duty free shop industry of Korea. Based on several theories, they present various criteria and statistical evidence such as K-firm concentration ratio, HHI, consumer substitutability, excess profit, and marketing costs. Results - In terms of consumer substitutability, it is difficult to confirm whether or not the Korean duty free shop industry is monopolistic. Notwithstanding monopoly characteristics in terms of market share, neither the company Lotte nor Shilla appear to have market dominating power. It is not easy for either of them to control prices or to achieve a much lower operational profit ratio due to a dominant bargaining power. Moreover, the license is not an economic rent. In this situation, it is not easy for these companies to obtain an excessive profit. Conclusions - Considering that most global duty free shops are trying to go upscale to improve bargaining power, it does not seem likely that rigid regulations are needed in the industry. Even though the Korean duty free industry ostensibly has a monopolistic structure, government and policy-makers should look beyond the surface. They should take global and other reasonable criteria into consideration when they establish or change regulation policies. Thorough understanding and appropriate support are needed for the Korean duty free shop industry. Additionally, duty free shops should position themselves as global companies struggling against unlimited international competition, rather than Korean domestic companies. At the same time, they need to give customers appropriate information about the benefits they provide.