• Title/Summary/Keyword: complex trace

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A Survey on the Heavy Metal Concentration of Soil Samples around Onsan Industrial Complex (온산공단(溫山工團)주변토양의 중금속(重金屬) 농도조사)

  • Lee, Su-Rae;Song, Ki-Joon
    • Korean Journal of Environmental Agriculture
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    • v.4 no.2
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    • pp.88-94
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    • 1985
  • In order to investigate the pollution potential of soils after the construction of Onsan Industrial Complex(non-ferrous metal refineries), concentrations of hazardous heavy metals were analyzed for soil samples collected from paddy, upland, orchard and forest soils around the Complex during the period of March 1978 to May 1979. The results are summarized as follows. 1) The concentrations of heavy metals (air-dry basis) for cultivated soil samples from 46 sites were obtained in the range of trace-9.3 ppm As, trace-0.6 ppm Cd, 4${\sim}$22 ppm Cu, trace-0.37 ppm Hg, 6${\sim}$43 ppm Pb and 27${\sim}$93 ppm Zn, which were regarded as non-polluted when compared with the whole Korea data for non-polluted paddy soils. 2) When the heavy metal concentrations were compared with respect to paddy, upland and orchard soils, no significant difference was observed in As, Cd, Cu and Zn whereas significant difference was observed in Hg and Pb. When they were compared with respect to region surrounding the Complex, no significant difference was observed in As, Cd, Hg whereas significant difference was observed in Cu and Pb. 3) Soil samples from several sites near Korea Zinc Refinery were contaminated with Cd, Pb and Zn, due to the accidental emission during its testing operation. Any further contamination was not observed after regular operation of the Refinery.

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Comparative study of constitutive relations implemented in RELAP5 and TRACE - Part II: Wall boiling heat transfer

  • Shin, Sung Gil;Lee, Jeong Ik
    • Nuclear Engineering and Technology
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    • v.54 no.5
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    • pp.1860-1873
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    • 2022
  • Nuclear thermal-hydraulic system analysis codes have been developed to comprehensively model nuclear reactor systems to evaluate the safety of a nuclear reactor system. For analyzing complex systems with finite computational resources, system codes usually solve simplified fluid equations for coarsely discretized control volumes with one-dimensional assumptions and replace source terms in the governing equations with constitutive relations. Wall boiling heat transfer models are regarded as essential models in nuclear safety evaluation among many constitutive relations. The wall boiling heat transfer models of two widely used nuclear system codes, RELAP5 and TRACE, are analyzed in this study. It is first described how wall heat transfer models are composed in the two codes. By utilizing the same method described in Part 1 paper, heat fluxes from the two codes are compared under the same thermal-hydraulic conditions. The significant factors for the differences are identified as well as at which conditions the non-negligible difference occurs. Steady-state simulations with both codes are also conducted to confirm how the difference in wall heat transfer models impacts the simulation results.

Effects of a Complex Exercise Program on the Distance between Knees and Balance in Individuals in their 20s with Genu Varum

  • Jeong, Beomcheol;Yoo, Kyungtae
    • Journal of International Academy of Physical Therapy Research
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    • v.11 no.4
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    • pp.2244-2252
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    • 2020
  • Background: Thera-Band, Narrow squats, Kinesiology taping helps in the reduction of loading on the knee joints. Despite the fact that the varus knee negatively affects the alignment of the lower extremities, most of the studies have analyzed each independently. Objectives: To investigate the effects of a complex exercise program consisting of elastic band exercises and squat exercises on the distance between the inner knees and balance in young adults with genu varum. Design: A cluster randomized controlled trial. Methods: The complex exercise group performed resistance exercises using an elastic band. The taping group used kinesiology tape on the vastus lateralis and biceps femoris. To select those to be included in the study, we measured the distance between the knees using digital Vernier calipers and to measure the balance ability, we used a balance training system. The data were analyzed with the independent t-test and paired t-test. Results: The study indicated a significant difference in the distance between the knees between the two groups, but no significant differences in the dynamic balance between the groups. Also, the static balance comparison between the groups according to the intervention method included the trace length, C90 area, C90 angle and velocity. There were no significant differences in the static balance between the groups. In addition, the complex exercise program was more effective than taping. Conclusion: The results of this study demonstrate that the complex exercise program and taping decrease the between both the knee and increase the balance.

Constituent of Natural Organic Matter (NOM) and its Effect in Water (물 속의 자연 유기물 성분이 환경에 미치는 영향)

  • Son, Hokyong;Erdei, Laszlo;Kim, Jong-Ho
    • Applied Chemistry for Engineering
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    • v.17 no.2
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    • pp.119-124
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    • 2006
  • Natural organic matter (NOM) should be carefully considered in terms of its constituent and effect because NOM is complex substances that occur in spatially and seasonally varying concentrations in natural water. This review presents characteristics of natural organic matter present in water. These compounds mainly include humic substances, carbohydrates, proteins (amino acids), hexosamines, fats, oils, greases, and trace organic compounds (endocrine disrupting chemicals and pharmaceuticals and personal care products).

Petrogeochemical Study on the Igneous Rocks of Southwestern Part of the Sangju Area (상주(尙州) 남서부(南西部)에 분포(分布)하는 화성암류(火成岩類)에 대(對)한 암석지화학적(岩石地化學的) 연구(硏究))

  • Choi, Bok Ryeol;Kim, Yong Jun
    • Economic and Environmental Geology
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    • v.23 no.3
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    • pp.329-342
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    • 1990
  • The purpose of this study is to clarify the nature of the differentiation and petrogenesis of igneous rocks in comparison with experimental results based on petrological and geochemical criteria. Study area is composed of the Precambrian granitic gneiss complex, Triassic meladiorite and biotite granodiorite, Jurassic biotite granite, and Cretaceous quartz porphyry. According to the data of EPMA, the clinopyroxene and orthopyroxene of meladiorite come under salite and hypersthene, respectively. Such results suggests that meladiorite is incipient differentiated products of basic magma under slow cooling condition. The petrochemical data of variation diagram of major element oxides vs. silica and of trace element oxide vs. silica, AMF triangle diagram and trace elements suggests that igneous rocks of study area are plutonic rocks belong to calc alkali rock series of the source of comagma intruded-emplaced in the order of meladiorite, biotite granodiorite and biotite granite by fractional crystallization of magma.

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Flame Atomic Absorption Spectrometric Determination of Trace Amounts of Thallium after Solid-Liquid Extraction and Preconcentration with Use of 1,10-Phenanthroline onto Benzophenone

  • Taher, Mohammad Ali
    • Bulletin of the Korean Chemical Society
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    • v.24 no.8
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    • pp.1177-1180
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    • 2003
  • Thallium is quantitatively retained by 1,10-phenanthroline and tetraphenylborate onto benzophenone in the pH range 0-11 from a large volumes of aqueous solutions of various samples. After filtration, the solid mass consisting of thallium complex and benzophenone is dissolved with 5 mL of dimethylformamide and the metal was determined by flame atomic absorption spectrometric. About 0.4 ㎍ of thallium can be concentrated from 400 mL of aqueous sample, where its concentration is as low as 1.0 ng/mL. Eight replicate determinations of 8.0 ㎍/mL of thallium in final dimethylformamide solution gave a mean absorbance of 0.160 with a relative standard deviation of 1.7%. The sensitivity for 1% absorption was 0.22 ㎍/mL. The interference of a large number of anions and cations has been studied and the optimized conditions developed were utilized for the trace determination of thallium in various alloys and biological samples.

NURBS Interpolation Strategies of Complex Surfaces in High Speed Machining

  • Ameddah, Hacene;Assas, Mekki
    • International Journal of CAD/CAM
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    • v.11 no.1
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    • pp.27-32
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    • 2011
  • The increase in the productivity and the assurance of quality machining on the NC machines depends on, amongst other things, the perfection of the programming using adequate methods of interpolation. The programming language is until now based on the code ISO 6983 which defines the principles of the code G. This latter is not well adapted to the new strategies of machining imposed by the machining of complex surfaces and machining at high speed with the increasingly more severe requirements of precision. The CNC which adopt the interpolation of NURBS (Non Uniform Rational B-spline) are very rare (FANUC Siemens${\ldots}$). Based on the advantages of NURBS (continuity, flexibility, smoothing$.{\ldots}$), new formats G are currently developed but their use is still very limited. Our work consists on putting forward these new approaches of programming using the interpolation of NURBS. For this reason, a program capable to trace NURBS trajectories under Visual BASIC 6.0 was developed. This program was used thereafter in CAM software for the generation of NURBS formats like their new formats NC.

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Development of dry-origin latent footwear impression on non-porous and semi-porous surfaces using a 5-methylthioninhydrin and L-alanine complex

  • Hong, Sungwook;Kim, Yeounjeung;Park, Jihye;Lee, Hoseon
    • Analytical Science and Technology
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    • v.30 no.2
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    • pp.75-81
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    • 2017
  • 5-methylthioninhydrin (5-MTN) is an amino acid sensitive reagent used for the development of latent fingermarks deposited on porous surfaces such as paper and wood. The present study demonstrates that the 5-MTN can be used as a latent footwear impression enhancement reagent, by reacting with trace multivalent metal ions, which are the main components of the latent footwear impression. 5-MTN and L-alanine complex (MTN-ALA) used for the latent footwear impression development was prepared, by mixing $4.5{\times}10^{-3}M$ 5-MTN (in methanol) and $4.5{\times}10^{-3}M$ L-alanine (in methanol) in 1:1 ratio, and keeping undisturbed at room temperature for 24 h. The latent footwear impressions were deposited on white and black non-porous surfaces (glass plate, polyethylene panel, polypropylene panel, acryl panel, polyvinyl chloride (PVC) panel, poly(methyl methacrylate) (PMMA) panel, acrylonitrile-butadiene-styrene (ABS) panel, tile), and a semi-porous surfaces (painted wood). The latent footwear impressions on these surfaces were treated with MTN-ALA complex by spraying. The fluorescence of footwear impressions (occurred due to the reaction between MTN-ALA and metal complexes) was observed under a 505 nm forensic light source and an orange barrier filter. The enhancement of latent footwear impression was achieved from black surfaces without any blurring. However, the fluorescence (enhancement) of footwear impression was not observed on the white PVC, PMMA, and ABS surfaces, because the incident light interfered and reflected on the surface. The sensitivity of MTN-ALA was superior to 2,2'-dipyridil, which is a representative non-fluorescing footwear impression enhancement reagent, and similar to 8-hydroxyquinoline, which is a representative fluorescing footwear impression enhancement reagent.

Magnetic Field Structure and Formation Scenario of the N159/N160 Star-Forming Complex in the Large Magellanic Cloud

  • Kim, Jaeyeong;Jeong, Woong-Seob;Pyo, Jeonghyun;Pak, Soojong;Park, Won-Kee;Kwon, Jungmi;Tamura, Motohide
    • The Bulletin of The Korean Astronomical Society
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    • v.42 no.1
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    • pp.38.3-39
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    • 2017
  • The N159 and N160 ionized regions in the Large Magellanic Cloud are an important extragalactic star-forming complex. The physical environments and the star formation stages are different in N159 and N160. We performed near-infrared polarimetry to those star forming regions with IRSF/SIRPOL 1.4-m telescope. Near-infrared polarization enabled us to trace the detailed structure of magnetic fields in star-forming regions. Through the polarimetric data of J, H, and Ks bands, we examined the magnetic field structures in the N159/N160 complex. In this presentation, we show complex distribution of the magnetic fields associated with dust and gas structures. We verify the local magnetic fields in each star-forming region, which appear to be related with local environments, such as interior and boundary of shell structure, star-forming HII regions, and boundaries between HII regions and dense dark clouds. We discuss the formation scenario of the N159/N160 complex suggested from the magnetic field structure.

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The Digestibility of Organic Trace Minerals along the Small Intestine in Broiler Chickens

  • Bao, Y.M.;Choct, M.;Iji, P.A.;Bruerton, K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.23 no.1
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    • pp.90-97
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    • 2010
  • An experiment was conducted to evaluate the effects of low concentrations of organic and inorganic dietary trace minerals on broiler performance and trace mineral digestibility along the small intestine of 35-day-old broiler chickens reared under floor-pen conditions. Eight hundred male, day-old Cobb broiler chickens were randomly allocated to 4 dietary treatments (25 birds per pen with 8 replicates per treatment). Broilers fed diets supplemented with 4, 20, 40 and 30 mg/kg, respectively, of Cu, Fe, Mn and Zn from organic chelates and inorganic salts achieved the same body weight gain as those supplemented at the NRC levels (8 mg Cu, 40 mg Fe, 60 mg Mn and 40 mg Zn/kg, respectively) from inorganic salts. However, birds fed a control diet without any supplementation at dietary levels of 7.4-8.8, 60.1-69.2, 14.6-15.4 and 19.1-20.6 mg/kg of Cu, Fe, Mn and Zn, respectively, had decreased feed intake and growth rate. There was no significant difference in the digestibility of Cu in all regions of the small intestine. Throughout the small intestine the apparent absorption of Mn from both organic and inorganic sources was small, whereas the digestibility of Zn seemed to be more complex, exhibiting differences in the apparent absorption due to both mineral source and intestinal site. Therefore, the digestibility of organic Zn was improved (p<0.01) in the ileum compared to inorganic Zn. The digestibility of Zn in the duodenum was smaller (p<0.05) than that in the ileum.