• Macromolecular Research
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• v.11 no.6
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• pp.437-443
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• 2003

A series of alternating and alternating block copolycarbonates containing the constituent groups of polysulfone was synthesized through a multi-step solution condensation method. For the regulation of block length, monodisperse oligomers were prepared by using a large excess of the bisphenols and were subsequently incorporated into the copolymer chains. Separating the unreacted bisphenols from the oligomers by dissolution/precipitation steps took advantage of solubility differences. The structures of the monomers, oligomers, and copolymers were characterized and confirmed by GPC, NMR spectroscopy, mass spectrometry, and elemental analysis. Monodispersity of the oligomers, which is critical for control over the block length in the copolymers, was confirmed by GPC and mass spectrometry. Of the two constituent groups of the polysulfone, the sulfone linkage stiffens the polycarbonate copolymer chain, while the ether linkage softens it.

• Steel and Composite Structures
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• v.22 no.1
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• pp.13-24
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• 2016

In the present paper, glass fibers are substituted partially with monofilament fishnet and polyester matrix for making the composites. The composite specimens were prepared in accordance with ASTM for analyzing the flexural strength and dynamic mechanical properties. Furthermore, machinability revealed the interaction of glass fiber and partial substituted monofilament fishnet fiber with the matrix. Fiber pullouts on the fractured specimen during the physical testing of the composites are also investigated by COSLAB microscope. The results reveal that the fishnet based composites have appreciably higher flexural properties. Furthermore, the glass fiber, woven roving and fishnet composite has more storage modulus and significant mechanical damping. The composite specimens were fabricated by hand lay-up method. Hence, these composites are the possible applications to develop the value added products. The results of this study are presented.

• Korean Journal of Pharmacognosy
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• v.43 no.2
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• pp.147-151
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• 2012

The marker constituent was isolated from Rubia cordifolia as a major compound. Quantitative method for the marker of the natural medicine was developed using HPLC-DAD and using established method the extract of Rubia cordifolia was evaluated. In addition, long term and accelerated stability test in the extract was examined for six months. No significant change in content of the marker constituent of the extract observed during the period of long term test.

• Journal of Welding and Joining
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• v.19 no.1
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• pp.75-81
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• 2001

The metallurgical study of microconstituents in transient liquid phase bonded joints of Ni-base single crystal superalloys, CMSX-2 and CMSX-4 was investigated employing MBF-80 insert metal. TLP bonding of specimens was carried out at 1,373~1,523K for 0~19.6ks in vacuum. Three types of microconstituents ; needle-like constituent, dot-like constituent and abnormal shape constituent were formed in the bonded interlayer during TLP bonding operation. All these microconstituents were identified as boride. Microconstituents contain a large percentage of Cr in the early stage of bonding. As increasing the holding time, the amount of Cr was decreased and the amount of W, Co and Re were increased. From the analysis results of electron diffraction pattern by TEM, composition of elements in microconstituents were into MBlongrightarrowM$_{5}$B$_3$longrightarrowM$_2$B type with the increased in holding time. It can be explained by the fact that the relative amount of boron in microconstituents was decreased when the holding time was increased.d.

• Journal of the Korean Ceramic Society
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• v.47 no.1
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• pp.86-91
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• 2010

Among various fuel cells, solid oxide fuel cells (SOFCs) offer the highest energy efficiency, when taking into account the thermal recycling of waste heat at high temperature. However, the highest efficiency and lowest pollution for a SOFC can be achieved through the sophisticated control of its constituent components such as electrodes, electrolytes, interconnects and sealing materials. The electrochemical conversion efficiency of a SOFC is particularly dependent upon the performance of its electrode materials. The electrode materials should meet highly stringent requirements to optimize cell performance. In particular, both mass and charge transport should easily occur simultaneously through the electrode structure. Matter transport or charge transport is critically related to the configuration and spatial disposition of the three constituent phases of a composite electrode, which are the ionic conducting phase, electronic conducting phase, and the pores. The current work places special emphasis on the quantification of this complex microstructure of composite electrodes. Digitized images are exploited in order to obtain the quantitative microstructural information, i.e., the size distributions and interconnectivities of each constituent component. This work reports regarding zirconia-based composite electrodes.

• Resources Recycling
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• v.11 no.4
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• pp.11-16
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• 2002

Analysis and separation of constituent materials of old car have been performed by using the industrial shredding line. For this aim, three old cars made by domestic automobile manufacturers, Sonata II, Sephia and Prince were chosen and delivered in pressed form without engine, tires and doors, etc. Shredding line was substantially composed of pre- and main-shredder. cyclone, magnetic separation, eddy current separation and man-power separation. From the separation of shredder products, iron scrap was observed to be the major material of old car accounting for 60.1 ％ of total weight and non-ferrous metals involving Al, Cu and Zn, etc. were about 2％. Light fluff, about 90％ of total fluff product, was comprised with plastic, fiber and sponge, etc. and the fraction of 5 cm undersize in light fluff was 70.5%. In case of heavy fluff, however. rubber and plastic were found to be the major constituent materials of it. Among the constituent materials of fluff, plastic showed the highest calorific value, more than 10,000 cal/gr and leather and rubber showed relatively high chlorine content, 10.3 and 2.55 wt%, respectively.

• Journal of Korean Medical classics
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• v.35 no.3
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• pp.21-31
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• 2022

Objectives : The Gyotae-hwan formula has traditionally been applied to conditions of fearful throbbing[怔忡] and insomnia due to disharmony of the Heart and Kidney, of which experimental and clinical research has been carried out while those on its pathological mechanism and constituent compatibility have been inadequate. Methods : Pathological mechanism and constituent compatibility of the Gyotae-hwan formula as listed in the 『Comprehensive Medicine According to Master Han』(韓氏醫通) and the『Simple Recipes for Four Disciplines』(四科簡效方) were analyzed. Findings from recent researches searched using the keywords '交泰丸' and '교태환' in the OASIS and CNKI databases were referenced as well. Results : The Gyo-tae hwan was first mentioned in the text 『Comprehensive Medicine According to Master Han』by Mao Han in terms of constituent medicinals and application while measurements and name of formula were not listed while the concept of harmony between the Heart and Kidney was mentioned. In the『Simple Recipes for Four Discipline s』 written by Shixiong Wang, measurements of constituent medicinals, usages and name of formula were finally mentioned, along with its efficacy to treat fearful throbbing and insomnia due to disharmony between the Heart and the Kidney. Conclusions : In conclusion, the Gyo-tae hwan uses Coptidis Rhizoma as chief herb and Cinnamomi Cortex as assistant herb to change the state of disharmony between the Heart and Kidney to a harmonious state, treating insomnia and fearful throbbing.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.10a
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• pp.213-216
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• 2009

In this study, three cold-rolled TRIP steels containing different Al content (0.04wt%, 1.0 wt.% and 2.00wt%) were fabricated to understand the complex effects of Al in TRIP steel. The influences of Al on microstructural evolution of cold-rolled TRIP steels have been analyzed by using advanced analysis techniques, such as transmission electron microscope (TEM) and three dimensional atom probe tomography (3D-APT). TEM results revealed that second phases such as bainte and retained austenite decrease with increase of Al content. In addition, 3D-APT was used to characterize atomic-scale distribution of alloying elements at the constituent phases. Through these analysis techniques, the advanced characteristics of constituent microstructure in TRIP steels were identified depending on Al contents in TRIP steels.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2002.10a
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• pp.1-4
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• 2002

The present study aims to design a multiplayer microstrip antenna with composite sandwich construction and to estimate structural behavior of this multiplayer structure for the next generation of structural surface technology. This is termed Surface-Antenna-Structure indicating that structural surface becomes antenna. Constituent materials were selected considering electrical properties as well as mechanical properties. For the antenna performance, antenna elements inserted into structural layers were designed for satellite communication at a resonant frequency of 12.5 GHz and final demonstration article was $16\times16$ array antenna. From electrical measurements it was shown that antenna performances were in good agreement with design requirements. Structural analysis showed this antenna structure was well designed for the mechanical rigidity. All constituent materials were characterized independently. The SAS concept is the first serious attempt at integration for both antenna and composite engineers and promises innovative future communication technology.

• Korean Management Science Review
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• v.24 no.2
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• pp.1-18
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• 2007

This paper presents a consolidated patent index to measure national technology innovation and science technology activation, as well as index for the main constituent such as corporation, research organization by comprehensive analysis of existing patent index. It is classified by macroscopic index and analytical index in the consolidated patent index, in which macroscopic index is to present a degree of innovation in national scientific innovation and is divided into the Consolidated Patent Index and Index for comparison between countries. The analytical index basically designed to measure R&D activity by the main constituent is divided to present by quantitative index utilizing bibliographical data in patent and other technical publication related therein, and qualitative index for analysis of bibliographical data. In this paper, the Consolidated Patent Index is presented by adding Creation Index representing for patent by developing excellent technology, Evaluation Index representing valuable technology thereof, and Utility Index representing applicability diffused.