• Title/Summary/Keyword: salt analysis

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Nonstoichiometry and Physical Properties of the Perovskite $CaGa_{1-x}Fe_xO_{3-y}$ System (페롭스카이트 $CaGa_{1-x}Fe_xO_{3-y}$계의 비화학량론과 물리적 성질)

  • Rho, Kwon Sun;Ryu, Kwang Hyun;Chang, Soon Ho;Yo, Chul Hyun
    • Journal of the Korean Chemical Society
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    • v.40 no.5
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    • pp.295-301
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    • 1996
  • A series of solid solutions of the $CaGa_1-xFexO_3-y$ system with the compositions of x=0.25, 0.50, 0.75, and 1.00 has been prepared at $1150^{\circ}C$ under an atmospheric air pressure. The structure, nonstoichiometric chemical formula, and the distribution of cations for the solid solutions are determined by X-ray diffraction analysis, Mohr salt titration, Mossbauer spectroscopic analysis. Their physical properties are discussed with electrical conductivity and magnetic measurements. The crystal system of all the compositions is a brownmillerite orthorhombic system from the X-ray diffraction analysis and the reduced lattice volume increases linearly with x value except that of the composition of x=0.25. All the solid solutions do not contain $Fe^{4+}$ ion and the mole number of oxygen vacancies or y value is 0.50 from Mohr salt analysis. The oxidation state of Fe ion, the coordination state, the structure change in the Brownmillerite-type structure, and the distribution of $Ga^{3+}$ and $Fe^{3+}$ ions are discussed with Mossbauer spectroscopic analysis. The electrical conductivity increases and activation energy decreases, as x value increases. The traditional semiconducting property of this system is described in terms of band theory. The compositions of x=0.50∼1.00 show a thermal magnetic hysteresis in the magnetic measurement with the cooling conditions, which is discussed in terms of the space group and Dzyaloshinsky-Moriya interaction.

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Using Harmonic Analysis and Optimization to Study Macromolecular Dynamics

  • Kim Moon-K.;Jang Yun-Ho;Jeong Jay-I.
    • International Journal of Control, Automation, and Systems
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    • v.4 no.3
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    • pp.382-393
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    • 2006
  • Mechanical system dynamics plays an important role in the area of computational structural biology. Elastic network models (ENMs) for macromolecules (e.g., polymers, proteins, and nucleic acids such as DNA and RNA) have been developed to understand the relationship between their structure and biological function. For example. a protein, which is basically a folded polypeptide chain, can be simply modeled as a mass-spring system from the mechanical viewpoint. Since the conformational flexibility of a protein is dominantly subject to its chemical bond interactions (e.g., covalent bonds, salt bridges, and hydrogen bonds), these constraints can be modeled as linear spring connections between spatially proximal representatives in a variety of coarse-grained ENMs. Coarse-graining approaches enable one to simulate harmonic and anharmonic motions of large macromolecules in a PC, while all-atom based molecular dynamics (MD) simulation has been conventionally performed with an aid of supercomputer. A harmonic analysis of a macroscopic mechanical system, called normal mode analysis, has been adopted to analyze thermal fluctuations of a microscopic biological system around its equilibrium state. Furthermore, a structure-based system optimization, called elastic network interpolation, has been developed to predict nonlinear transition (or folding) pathways between two different functional states of a same macromolecule. The good agreement of simulation and experiment allows the employment of coarse-grained ENMs as a versatile tool for the study of macromolecular dynamics.

A Study on the Electric Field Analysis of EHV Overhead Distribution Lines Using Maxwell 3D - I (Maxwell 3D를 이용한 특고압 배전선로의 전계해석에 관한 연구 - I)

  • Seo, Y.P.;Park, S.W.;Kim, C.H.;Won, C.Y.;Nam, K.D.;Ha, S.N.
    • Proceedings of the KIEE Conference
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    • 1996.07b
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    • pp.847-849
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    • 1996
  • As the power demands increases, one of the most important data is inside electric field of equipment in designing of insulators ami insulated wire for EHV distribution line. So far finite element analysis method is widely used to calculate this electric field. However as the shape of insulator becomes complicated, it is difficult in producing the mesh which suitable the shape. Especially, we have many difficulty that produce dense fine mesh only where the electric field is concentrated. Therefore in this paper, we perform the each conditional analysis of electric field using the Maxwell 3D Simulator to recover this defects. And we try to analyze electric field through the conventional 2 dimensional and 3 dimensional analysis in case of salt contamination on the surface of a insulator.

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Structural and Magnetic Properties of the Brownmillerite $Ca_2Al_xFe_{2-x}O_5$ System

  • 김귀야;로권선;여철현
    • Bulletin of the Korean Chemical Society
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    • v.16 no.10
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    • pp.934-938
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    • 1995
  • A series of solid solutions in the Ca2AlxFe2-xO5 (x=0.00, 0.50, 0.66, 1.00 and 1.34) system with brownmillerite structure has been synthesized at 1100 ℃ under an atmospheric air pressure. The solid solutions are analysed by powder x-ray diffraction analysis, Mohr salt titration, thermal analysis, and Mossbauer spectroscopic analysis. The x-ray diffraction analysis assigns the compositions of x=0.00 and 0.50 to the space group Pcmn and those of x=0.66, 1.00, and 1.34 to the Ibm2. Mo&ssbauer spectra have shown the coordination state and disordering of Al3+ and Fe3+ ions. The substituting preference of Al3+ ions for the tetrahedral site decreases with increasing x value. Magnetic susceptibility of the system has been measured in the temperature range of 5 K to 900 K. The solid solutions of the compositions of x=0.00, 0.50 and 0.66 have shown a thermal hysteresis and the thermoremanent magnetization gap decreases with increasing x value in the above systems. However the compositions of x=1.00 and 1.34 do not show the hysteresis. The exchange integral is calculated from Fe3+ ion occupancy ratio. The integral decreases with x value and thus the magnetic transition temperature decreases with the increasing x value.

Analysis of Spatial Distribution of Hypertension Prevalence and Its Related Factors based on the Model of Social Determinants of Health

  • Kim, Min Jung;Park, Nam Hee
    • Research in Community and Public Health Nursing
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    • v.29 no.4
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    • pp.414-428
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    • 2018
  • Purpose: The purpose of this study is to identify the spatial distribution of hypertension prevalence and to investigate individual and regional-level factors contributing to the prevalence of hypertension in the region. Methods: This study is a cross-sectional research using the 2015 Community Health Survey. Total 64,473 people from 7 metropolitan cities were used for the final analysis. Geoda program was adopted to identify the regional distribution of hypertension prevalence and analyzed by descriptive statistics, one-way ANOVA and correlation analysis using SPSS statistics 23.0 program. Multi-level analysis was performed using SPSS (GLMM). Results: The prevalence of hypertension was related to individual level factors such as age, monthly household income, normal salt intake, walking practice days, and regional level factors including number of doctors per 10,000 population, number of parks, and fast food score. Besides, regional level factors were associated with hypertension prevalencies independently without the effects of individual level factors even though the influences of individual level factors ware larger than those of regional factors. Conclusion: Respectively, both individual and regional level factors should be considered in hypertension intervention programs. Also, a national level research is further required by exploring various environmental factors and those influences relating to the hypertension prevalence.

A Study on Surface Landscape Change and Sedimentary Environment of the Dongcheon Estuary through Aerial Photographs and Sediment Analysis (항공사진 및 퇴적물 분석을 통한 순천 동천하구의 지표경관 변화 및 퇴적환경 연구)

  • Lee, Ye-Seul;Lim, Jeong-Cheol;Jang, Dong-Ho
    • Journal of The Geomorphological Association of Korea
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    • v.28 no.1
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    • pp.35-50
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    • 2021
  • In this study, we analyzed the changes in the topographical landscape and the sedimentary environment to evaluate the ecological value of the Dongcheon Estuary and protect the wetland, and presented the conservation management method of the Dongcheon Estuary. Based on the result of topographical landscape analysis, agricultural land tended to decrease continuously, and artificial structures gradually increased. Moreover, in sediment analysis, the Dongcheon Estuary showed both the characteristics of river sediments and coastal sediments, and in some areas problems such as acidification and nutritional imbalance appeared. Therefore, in order to protect and manage the Dongcheon Estuary with high ecological value, it is necessary to limit the development around micro topography and minimize the artificial damage in the Dongcheon Estuary. In addition, efforts such as securing facilities for reducing pollutants and freshwater wetlands for pollutants, that flow in from nonpoint pollutants are required.

Genome-Wide Comprehensive Analysis of the GASA Gene Family in Peanut (Arachis hypogaea L.)

  • Rizwana B.Syed Nabi;Eunyoung Oh;Sungup Kim;Kwang-Soo Cho;Myoung Hee Lee
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2022.10a
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    • pp.231-231
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    • 2022
  • The GASA protein (Gibberellic acid-stimulated Arabidopsis) are family of small cysteine-rich peptides found in plants. These GASA gene family mainly involved in biotic/abiotic stress responses and plant development. Despite being present in a wide plant species, their action and functions still remain unclear. In this study, using the in-silico analysis method we identified 41 GASA genes in peanuts (Arachis hypogaea L.). Based on the phylogenetic analysis 41 GASA genes are classified in the four major clusters and subclades. Mainly, clusters IV and III comprise the majority of GASA genes 15 and 11 genes respectively, followed by cluster I and cluster II with 9 and 6 genes respectively. Additionally, based on in-silico analysis we predicted the post-transcriptional and post-translational changes of GASA proteins under abiotic stresses such as drought and salt stress would aid our understanding of the regulatory mechanisms. Hence, a further study is planned to evaluate the expression of these GASA genes under stress in different plant tissues to elucidate the possible functional role of GASA genes in peanut plants. These findings might offer insightful data for peanut advancement.

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Physicochemical and Sensory Characteristics of Doenjang Made by Traditional Methods (전통적인 방법으로 제조된 된장 제품의 이화학적 및 관능적 특성에 대한 연구)

  • Byun, Myung-Woo;Nam, Tan-Gong;Chun, Myoung-Sook;Lee, Gyu-Hee
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.10
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    • pp.1543-1548
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    • 2014
  • To study traditional Doenjang characteristics, Doenjang was purchased from five different provinces: Chungcheong (CC), Gangwon (GW), Gyeonggi (GG), Gyeongsang (GS), and Jeolla (JL). To determine physicochemical characteristics, contents of reducing sugar, amino type nitrogen, salt, pH, and acidity were analyzed. The sensory characteristics were analyzed by sensory descriptive analysis. Reducing sugar content was highest for Doenjang from GW province. Amino type nitrogen content was highest for Doenjang from JL province. The salt content was highest in Doenjang from CC and GS provinces. After principal component analysis (PCA) based on sensory descriptive analysis, salty taste and aftertaste were highly correlated with overall acceptance. In the correlation analysis among chemical compounds and overall acceptance, Doenjang contained low reducing sugar content, and high pH value was positively correlated with overall acceptance. In conclusion, Doenjang with high pH value and salty taste and aftertaste have high overall acceptance.

Selection and Agronomic Traits of Radiation-induced Variants in Rice (방사선 이용 벼 돌연변이 계통 선발 및 농경 형질조사)

  • Lee, In-Sok;Kim, Dong-Sub;Lee, Sang-Jae;Song, Hi-Sub;Lim, Yong-Pyo;Lee, Young-Il
    • Journal of Plant Biotechnology
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    • v.30 no.1
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    • pp.19-25
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    • 2003
  • Radiation technique in agriculture was initiated to develop mutant rice. Seeds of Daechungbyeo rice were irradiated with 250 Gy gamma ray for the purpose of inducing and selecting rice variants. Some quantitative traits of the variants in M$_{8}$ generation were evaluated and RAPD analysis was carried out. Variants showed a wider range of agronomic characteristics in both a positive and a negative direction compared with their original variety. The new mutants were characterized by an increased or decreased in plant height, lodging resistance and shorter panicle. RAPD analysis showed that polymorphic bands were presented in most of the primers. In comparison with the original variety, variants were classified into four groups through UPGMA analysis. Among mutants no. 91, 139, 140 and 141 was ranked as salt tolerance and the proline content of these mutants was more increased than that of original variety. The lines of 139, 140 and 141 had the highest genetic distance as compared to original variety in the dendrogram. It is expected that such variants will be useful not only for studying molecular genetics but also for breeding research and genetic analysis.s.

Change of quality properties of Doenjang according to soaking method in brine (장 담금법에 따른 된장의 품질 특성 변화)

  • Choi, Bo-Young;Gil, Na-Young;Park, Shin-Young;Cho, Yong-Sik;Kim, So-Young
    • Food Science and Preservation
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    • v.24 no.7
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    • pp.923-933
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    • 2017
  • This study was carried out to examine the quality characteristics of Doenjang manufactured with or without soaking Meju in brine according to salt concentrations (8 and 12%) during fermentation for 6 months. The moisture content and salinity of Doenjang fermented for 6 months were 54.9-60.3% and 7.8-12.5%, respectively. Doenjang using soaking Meju in brine had higher pH and lower titratable acidity than that using non-soaking Meju. The reducing sugar content in all samples was increased until 2 months and then decreased regardless of soaking Meju, especially that of non-soaking 8% Doenjang was the highest. The 8% low-salt Doenjang was shown the highest amino-type nitrogen content, especially the soaking Doenjang was higher than the non-soaking Doenjang. ${\alpha}$-amylase activity of all samples during fermentation were continuously decreased from 0.91-0.94 Unit/g to 0.01-0.06 Unit/g, especially the 8% soaking Doenjang was shown the highest activity after 2 months. Total bacterial count of the soaking Doenjang at the 6 months was in range of 7.8-8.0 log CFU/g and that of the non-soaking Doenjang was in range of 7.2-7.5 log CFU/g. By taste analysis, the 8% soaking Doenjang was shown the similar taste pattern with commercial Doenjang. In conclusion, the 8% low-salt Doenjang manufactured with soaking Meju in brine was a suitable concentration in order to reduce salt intake.