• Title/Summary/Keyword: Sigma S

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The Crystal and Molecular Structure of 25,26,27,28-Tetrnacetoxy[4]Arene${\cdot}$Monohydrate (25,26,27,28-테트라아세트오키시[4]에렌${\cdot}$일수화물의 결정 및 분자구조)

  • Choong Tai Ahn;Kwanghyun No
    • Journal of the Korean Chemical Society
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    • v.37 no.3
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    • pp.344-350
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    • 1993
  • 25,26,27,28-Tetraacetoxycalix[4]arene·monohydrate is orthorhombic, space group Pbca with a = 14.979(4), b = 15.154(4), c = 27.890(3) ${\AA}$, Z = 8, V = 6330.6 ${\AA}^{-3}$, D$_c$ = 1.28 $g{\cdot}cm^{-3}$, (Mo K${\alpha}$) = 0.71069 ${\AA}$, ${\mu}$ = 0.86 cm$^{-1}$, F(000) = 2600, and R = 0.069 for 3376 unique observed reflections with I > 1.0 ${\sigma}$(I). The structure was solved by direct methods and refined by cascade diagonal least-squares refinement. All the C-H bond lengths(= 0.96 ${\AA}$), the methyl groups and the methylene groups are fixed and refined as the rigid groups with ideal geometry. The macrocycle exists in the 1,3 alternate conformation (by Conforth) making the angles of 110.7, 684, 113.7 and 68.8$^{\circ}$ between the benzene rings and the methylenic mean plane, and four each acetoxy groups are twisted away from their own benzene rings with the angles of 68.2, 97.6, 78.9 and 71.3$^{\circ}$, respectively. The relative dihedral angles between two opposite side of the benzene rings are 135.6$^{\circ}$ for the rings (1) and (3) and 135.2$^{\circ}$ for (2) and (4). A water molecule which has nearly the same height of the methylenic plane of the macrocycle in the c-axis, is located within the distances of 2.942(5) ${\AA}$ from the O(8) atom of the carbonyl group and 2.901 ${\AA}$ from, another O(2)(1/2-x, -1/2+y, z). The shortest contact between the molecule is 3.193 ${\AA}$ from the O(4) to the C(3)(1/2+x, 1/2-y,-z).

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The Effect of Ex-prisoner's Perception of Stigma on Trust in Interpersonal Relationship (낙인에 대한 출소자의 인식이 대인관계에서 신뢰에 미치는 영향)

  • Gong, Jung Sik
    • Korean Security Journal
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    • no.57
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    • pp.57-84
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    • 2018
  • This study assumes that the perception of the ex-prisoner's against stigma will affect trust in interpersonal relationship. Prior studies have suggested that there is a stigma at the base of the awareness where people avoid and discriminate against ex-prisoner's. This in turn affects ex-prisoner's' recividicism, but there is no study about ex-prisoner's perception of stigma in Korea. Although stigma can be explained in numerous ways, this study is based on the opinion of Phillips(2016), which divides the subscale of stigma as perceived public stigma, perceived personnel stigma, and self stigma. He insisted that ex-prisoner's believe perceived public stigma higher than self-stigma. these results are consistent with this study. However, it is important to note that although ex-prisoner's are more aware of public stigma than self-stigma, they are actually more influenced by self stigma in pereonal relationships. This means that ex-prisoner's are more susceptible to internal psychological awareness than external social recognition. Therefore, the development and intervention of the program to overcome the internal self-stigma of the released prisoner is required. In this study, first, stigma, especially self-stigma turned out to have influence on the interpersonal trust. Therefore, as self-stigma level increased, the interpersonal trust decreased in most cases. Second, it was shown that stigma has the greatest influence on children out of family members, co-workers out of social relationship, self trust out of general relationship in. This confirms that stigma is a factor that greatly influences relationship between important people for ex-prisoner's. Third, since self-sigma negatively reestablish self-identity, make individuals recognize themselves as deviators and show bad lifestyle, which lead them to become habitual offender, ex-prisoner's need to make efforts to overcome self-stigma, and development and intervention of program that can make ex-prisoner's have positive self identity is requested. Fourth, although participants in the study were only male, it seems that there is difference in recognition of stigma by gender, and influence of stigma not only on interpersonal relationships, but also on social reintegration and recidivism imply that these might be good future research topics.

Effects of Administration of Pyritum on Fracture Healing in Mice (자연동(自然銅)이 초기 골절 생쥐 정강이뼈의 Re-modeling에 미치는 영향)

  • Shin, Kyung-Min;Jung, Chan-Yung;Hwang, Min-Seop;Lee, Seung-Deok;Kim, Kyung-Ho;Kim, Kap-Sung
    • Journal of Acupuncture Research
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    • v.26 no.5
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    • pp.65-75
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    • 2009
  • Objectives : Pyrite is one of the important prescriptions that has been used in oriental medicine for healing of fracture. It is reasonable, therefore, to postulate that native copper affects the process of bone metabolism and bone formation. The purpose of this study is to discover the effect of Pyrite on the healing of tibia fracture. Methods : 1. In vitro test : MG-63 cell in human body and the Pyritum in the ratio of 0.5mg/ml, 1.0mg/ml, 1.5mg/ml, 2.0mg/ml were incubated for 24 hours. After 24 hours, RNA was extracted via trizol reagent (Sigma, USA). In order to understand the activation of osteoblast, the level of OPN mRNA, osteopontin, was measured. 2. In vivo tesgroups normal group, control group and experimental group. Left tibia bones of mice in CON and JT groups were fractured by bone cutters. Pyrite was orally administered to the experimental group. After 14 days, each group's tibia specimen was constructed to observe changes in activation of proinflmmatory cytokines in relation to MIF and IL-6. Also, proliferation of osteoblast and osteopontin were measured via changes in levels of OPN and OPN mRNA. Results : In jn-Titro test, the level of OPN mRNA, osteopontin production was remarkably increased in Pyritum-treated MG-63 cells. In in-vitro test, fractured area in external tibia morphology was increased more in the JT group than that of the CON group. Osteogenesis, endochodrial ossification, and osteoid in fractured area were also increased more in the JT group than that of the CON group. Increase in OPN mRNA, osteopontin level and osteoblast's proliferation were observed. Activation of MIF and IL-6 was confirmed from the fracture region. Conclusions : From the result, development of a new stimulator in healing fracture via pyrite is expected.

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Characterization of Low-Trans Solid Fat from Canola and Fully Hydrogenated Soybean Oil by Lipase-Catalyzed Interesterification Reaction (효소적 에스테르 교환 반응 시 카놀라유와 대두극도경화유의 비율에 따른 저트랜스 고체지방의 특성)

  • Kim, Young-Joo;Lyu, Hyun-Kyeong;Lee, Seon-Mo;Lee, Ki-Teak
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.39 no.9
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    • pp.1320-1327
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    • 2010
  • Lipase-catalyzed interesterification of canola (CO) and fully hydrogenated soybean oil (FHSBO) at different weight ratios (70:30, 75:25, and 80:20) was performed in a batch type reactor to produce low-trans solid fats. Each reaction was conducted in the shaking water bath for various reaction times (1, 3, 6, 18 and 24 hr) at 70oC and 220 rpm using Lipozyme TLIM (20 wt% of total substrate) from Thermomyces lanuginosus. After 24 hr reaction, solid fat content (SFC) by differential scanning calorimetry (DSC), fatty acid and triacylglycerol (TAG) composition of low-trans solid fats were determined. SFC of the products was reduced when the content of canola oil in the reaction mixture was increased. Major fatty acids were stearic acid (C18:0), oleic acid (C18:1) and linoleic acid (C18:2). Trans fatty acid content in the low-trans solid fats showed less than 0.3 wt%. In the HPLC analysis, major TAG species showed LOO (linoleyl-oleoyl-oleoyl), OOO, POO/SOL, SOO, and SOS.

A Study on the Structural Deformations in the Sedimentary Layer Resulted from Magma Intrusion (마그마관입에 의한 상부퇴적층의 변형에 관한연구)

  • Min, Kyung Duck;Kim, Won Young
    • Economic and Environmental Geology
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    • v.10 no.1
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    • pp.37-48
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    • 1977
  • The earth's crust is unceasingly undergoing deformations because of the forces acting upon it. The relationship between the tectonic forces and the resulting deformations are found from the states of stresses in the earth's crust induced by these forces. The study has been attempted to analyze the deformations of the overlying sedimentary layers, which are deformed by the magma intrusion along its lower boundary. The elastic model is constructed to analyze the geologic structures, by means of the theory of elasticity, and then the appropriate boundary conditions are given. The solution of the Airy stress function which satisfies the given boundary conditions is derived from the analytic method. The internal stress distributions of the deformed elastic model layer are portrayed by principal stress trajetories, and then the corresponding potential faults and joints systems are predicted from the Coulomb-Mohr failure criterion. The internal displacement distributions are shown by the calculated displacement components vectors, namely horizontal, vertical and net components. Results of the numerical calculations show the developments of some geologic structures as follows; (1) one set of shear joints and or two sets of shear joints which are oppisite directions, and one set of extension joints parallel to the ${\sigma}_1$ direction, (2) one set of high angle thrusts and normal faults, (3) symmetric fold; both limbs are dipping in opposite direction with low angle. The field work at the Wall-A San area, located near Jinju City, in southern Korea, had accomplished to compare the field structures with the predicted ones. The results of the comparison exhibits the developments of joint and fault systems satisfactorily consistent with each others. But the area does not show any type of folding, in spite of the intrusion of a granodiorite massif, this fact is one of the important features of the whole Kyungsang sedimentary basins of Mesozoic age distributed at the south-eastern parts of Korea. For this reason, it is thought that the magma intrusion had occurred with extremly low pressure. The geologic structures have been modified by the erosion and weathering throughout the geologic time, and the conditions of the sedimentary layers (width, thickness and radius of magma) are not the same as before, being intruded by the magma. To enlighten this, it is preferable to study these geologic structures with analyses of various types of rheological models.

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Study on the Manufacturing of Chitosan Using Krill(Euphausia superba Dana) and Quality Characteristics (크릴을 이용한 키토산 제조 및 품질 특성)

  • Do, Jeong-Ryong;Park, In-Sung;Rhee, Seong-Kap;Kim, Dong-Soo
    • Applied Biological Chemistry
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    • v.43 no.4
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    • pp.309-313
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    • 2000
  • For the use of Antartic krill(Euphausia superba Dana) as food resource, general composition, extracting condition of chitin and quality characteristics of chitosan were investigated. General composition of frozen krill(Euphausia superba Dana) was consisted of moisture 79.0%, protein 13.1%, lipid 4.0%, VBN 7.7mg%, ash 2.7%, others 1.2% and that of dried krill powder was moisture 5.6%, protein 56.1%, lipid 18.8%, ash 11.4%, others 8.1%. The condition of chitin extraction from krill powder was treated with 1N NaOH at $40^{\circ}C$ for removing protein, 1N HCl for excepting mineral substances and methanol for decoloring. The yield of chitin by new procedure developed was 3.7%. The composition of extracted chitin contents was moisture 7.1%, ash 0.4%, protein 3.5%, lipid 3.1%. The results of degree of deacetylation in chitosan at 50% NaOH, $121^{\circ}C$, for 2 hrs was showed 82%. At the same alkali concentration and reaction concentration, a longer reaction time gave a decreased degree of deacetylation. The apparant viscosity was 0.09241 Pa in 1% chitosan from krill and 0.13826 Pa in standard chitosan.

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A Study on the Introduction of Linear Programming Model into the Management of Korean Coastal and Offshore Fisheries (한국 연근해어업의 합리적 관리를 위한 LP모형의 도입방안에 관한 연구)

  • 박장일
    • The Journal of Fisheries Business Administration
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    • v.25 no.1
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    • pp.37-59
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    • 1994
  • Many studies to cope with the present problems of Korean coastal and offshore fisheries has been performed, but these were done partly in necessities and general studies for Korean inshore and offshore fisheries are in early stage. Most of these studies adopted analytical way of approach for each fishery individually and they could not reflect the effect of correlated interaction among fisheries on the several common species/stocks, and thus optimal effort allocation was impossible. To consider general fisheries and optimal effort allocation among competing mixed species, a linear programming (LP) approach is applied in this study and introduced into 16 important inshore and offshore fisheries with 13 constraining species which were chosen by annual yield order. This study is not based on the biological interaction among species (i.e., prey - predator system) but the technological interaction between species and fishing efforts. For the application of LP model in these fisheries, the standardization of fishing efforts through different fishing gears could not be successful and a new way of effort standardization through CPUE for vessel tonnage was originated. Total standardized fishing effort on a particular species i, Ei, is computed as the linear summation of standardized fishing effort generated by each fishery j. That is, (equation omitted) where $f_{j}$ is the total vessel tonnage of fishery j and aij is the coefficients contributing to the standardized fishing effort per ton for species i taken in fishery j. The total fishing effort level on species i due to both directed fishing and by - catch can thus be accounted in the aij's. Optimal effort allocation among the j fisheries may be considered a minimizing problem (minimize $\Sigma$ $f_{j}$), subject to the constraints that standardized fishing effort levels on particular species are maintained at, above, and below certain predefined levels. Fishing effort goals for individual species can be based on various biological and/or economic criteria, i.e., fishing effort level generating maximum sustainable yield and/or maximum economic yield. But in this study the $F_{0.1}$ criteria which was accepted as an approximate level for $F_{mey}$ by Outland and Boerema's (1973) study. The findings of this study are, (1) LP model can be applied to the Korean inshore and offshore fisheries giobally. (2) Through a new way of combining multiple different fisheries' efforts for a particular species together generating standardized fishing effort, Schaefer curve could be applied to the complex system successfully. (3) The results of this study for total reduction scale were mostly the same as those of prior studies, but different much from the individual scales of reduction. This study showed the necessities for exploitation of more concrete parameters to put into consideration of profitability of fisheries and social factors, and this model can be modified according to the actual constraints. Also, considering the age structure of stocks, this model can be developed into better one for better fisheries management.ent.

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A Study on Preparation of Colloidal Gas Aphrons and Stability (Colloidal Gas Aphrons의 제조와 안정성에 대한 연구)

  • Yoon, Mi-Hae;Cho, Dae-Chul
    • Journal of Korean Society of Environmental Engineers
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    • v.29 no.6
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    • pp.670-677
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    • 2007
  • The stability of CGAs(colloidal gas aphrons) prepared from non-ionic and ionic surfactants was investigated. Those surfactants were sodium dodecyl sulfate(SDS), Triton X-100, Tween 80 and Quillaja Saponin. The stability of CGAs prepared from single surfactants or mixed surfactants(two components) using a CGA generate. was investigated as functions of temperature, surfactant concentration and stirring time. Saponin among the single surfactants has shown the longest duration time(143 min) and then, Triton X-100, SDS, and Tween 80 were followed by at room temperature. In case of CGAs heated up to $70^{\circ}C$, SDS endured for 116 min but Saponin lasted for only 105 mit which was a considerable reduction of the duration time of CGAs at room temperature. For mixed surfactant pairs, stability of any one pairs stood between the two. That meant no synergic effect for surfactant blending. At the higher temperature, Saponin+Triton X-100 was disclosed to be the lowest, 53 min meanwhile Saponin+SDS was the highest at ambient temperature. The CGAs, initially about 140 ${\mu}m$ in diameter, began to grow right after the agitation to be about 190 ${\mu}m$ owing to coalescence of the bubbles and then became to collapse. When heated, CGAs including Saponin tended to be smaller while the others to be larger. In summary, we found that the stability of CGAs or the duration time was greater for single surfactants and at room temperature rather than for mixed surfactants that caused substantial intermolecular interactions in the CGA structure and at the higher temperature.

Growth of Hexagonal Boron Nitride Thin Films on Silicon Using a Single Source Precursors

  • Boo, Jin-Hyo;Lee, Soon-Bo;Casten Rohr;Wilson Ho
    • Proceedings of the Korean Vacuum Society Conference
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    • 1998.02a
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    • pp.120-120
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    • 1998
  • Boron nitride (BN) films have attracted a growing interest for a variety of t technological applications due to their excellent characteristics, namely hardness, c chemical inertness, and dielectrical behavior, etc. There are two crystalline phases 1551; of BN that are analogous to phases of carbon. Hexagonal boron nitride (h-BN) has a a layered s$\sigma$ucture which is spz-bonded structure similar to that of graphite, and is t the stable ordered phase at ambient conditions. Cubic boron nitride (c-BN) has a z zinc blende structure with sp3-bonding like as diamond, 따ld is the metastable phase a at ambient conditions. Among of their prototypes, especially 삼Ie c-BN is an i interesting material because it has almost the same hardness and thermal c conductivity as di없nond. C Conventionally, significant progress has been made in the experimental t techniques for synthesizing BN films using various of the physical vapor deposition 밍ld chemical vapor deposition. But, the major disadvantage of c-BN films is that t they are much more difficult to synthesize than h-BN films due to its narrow s stability phase region, high compression stress, and problem of nitrogen source c control. Recent studies of the metalorganic chemical vapor deposition (MOCVD) of I III - V compound have established that a molecular level understanding of the d deposition process is mandatory in controlling the selectivity parameters. This led t to the concept of using a single source organometallic precursor, having the c constituent elements in stoichiometric ratio, for MOCVD growth of 삼Ie required b binary compound. I In this study, therefore, we have been carried out the growth of h-BN thin f films on silicon substrates using a single source precursors. Polycrystalline h-BN t thin films were deposited on silicon in the temperature range of $\alpha$)() - 900 $^{\circ}$C from t the organometallic precursors of Boron-Triethylamine complex, (CZHs)3N:BRJ, and T Tris(dimethylamino)Borane, [CH3}zNhB, by supersonic molecular jet and remote p plasma assisted MOCVD. Hydrogen was used as carrier gas, and additional nitrogen w was supplied by either aDlIDonia through a nozzle, or nitrogen via a remote plasma. T The as-grown films were characterized by Fourier transform infrared spectroscopy, x x-ray pthotoelectron spectroscopy, Auger electron spectroscopy, x-ray diffraction, t transmission electron diffraction, optical transmission, and atomic force microscopy.roscopy.

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Evaluation on Stress-Strain-Strength Behavior of the Textile Encased Soils via Triaxial Compression Tests (삼축압축시험을 통한 섬유로 구속된 흙의 응력-변형률-강도 거동 평가)

  • Yoo, Wan-Kyu;Kim, Byoung-Il;Cho, Wanjei
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.33 no.2
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    • pp.643-653
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    • 2013
  • Recently, there are an increasing number of studies on the method of wrapping the outer wall of granular piles with geosynthetic fibers such as geotextile or geogrid that has a certain level of tensile strength as an alternative method for the ground improvement techniques. In this study, triaxial compression tests are performed on the sand and clay specimen encased with various textiles to evaluate the reinforcing effect with regard to the tensile strength of the textile. Furthermore, triaxial compression tests are performed on the clay specimen inserted by sand only and sand encased with geosynthetics to compare behavioral differences between the conventional sand compaction pile and geosynthetic encased sand pile with regard to the replacement ratio, ${\alpha}_s$ and the tensile strength of the geosynthetics. Based on the experimental results, the strength enhancement due to the textile is affected by the longitudinal tensile strength rather than the transverse one of the applied textile. The effect of the confinement by the textile encasement results in the large increase of the cohesions. The overall behaviors, such as shear strength, pore pressure parameter at failure and stress ratio, of the geosynthetic encased sand pile is quite different from those of the conventional sand compaction pile.