• Title/Summary/Keyword: preparation condition

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A Study on Mechanical Shearing Process for Tailored Blank Welding (테일러드블랭크 용접을 위한 전단 공정 연구)

  • 유병길;이경돈
    • Journal of Welding and Joining
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    • v.17 no.2
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    • pp.66-75
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    • 1999
  • Weld bead quality in tailored blank(TB) is critically affected by edge preparation of sheets. The edge quality of prepared sheets for TB can be classified into straightness and the cross section quality of sheared plane such as a ratio of shear face, shear plane angle, etc. In order to have a good edg quality for butt-welding sheets, precision shearing will be recommended. In this paper, the feasibility of a conventional mechanical shearing as the edge preparation for tailored blanks is studyied. It reveals that fine shearing may not be the unique solution as it is generally accepted. To obtain the good shearing condition with a conventional mechanical shearing, experiments were carried out using Tahuchi method. The major parameters affecting a sheared contour are the clearance between upper blade and lower blade, and shear angle. The optimal shearing condition yields a very good straightness along the entire length of the cut, which gives a butt joint gap less than 10% of the base material thickness. The good cross section of sheared plane is also achieved in the optimal shearing condition such as a ratio of the shear face above 65%, a cross section's shear plane angle above 85%, little burr, which is providing finally good weld beads.

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A matrix-typed, sustained-releasing agent comprising agrochemical and the sustained-releasing product analysis for the preparation (매트릭스형의 서방성(Sustained-Releasing) 수분 인지방출 농약제제 및 그 제조를 위한 서방성 방출분석)

  • Park, Hae-Jun;Kim, Sung Ho;Kim, Hwa Jung
    • Analytical Science and Technology
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    • v.20 no.2
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    • pp.176-182
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    • 2007
  • The present study relates to a matrix-typed, sustained-releasing agent comprising agrochemical effective ingredients being capable of recognizing a content of moisture, and a preparation method thereof. The curdlan solution added to acid was formed matrix which has unique network structure. The matrix treated by heat lost water solubility. The network structure of matrix was opened in the aquatic condition but closed again in dry condition. Therefore, in the sustained-releasing formulation system, an agrochemical effective ingredient was released from the formulation only in the aquatic condition. Use of the composition according to the product can control a manifesting time of effects of agrochemicals and can provide agrochemicals with reduced harmful damages.

Synthesis of FAU(Faujasite)-type Zeolite with Variation of Synthesis Condition (합성조건의 변화에 따른 FAU(Faujasite)형 제올라이트의 합성)

  • 임형미;김봉영;남중희;안병길;오성근;정상진
    • Journal of the Korean Ceramic Society
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    • v.40 no.2
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    • pp.132-138
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    • 2003
  • The effect of synthesis condition, type of starting materials, mole ratio, mixing. aging, and crystallization temperature and time, on the size of FAU-type zeolite has been studied. Different mixing route may lead to the different phase of zeolite even with the same starting materials. In general, the size of particles is smaller after aging, especially at lower aging temperature. Two step mixture gel preparation method resulted to not only the reduction of crystallization time but also that of particle size, but without the aging of two mixture gels before the preparation of the overall gel in the second step, only the crystallization time was reduced, not the particle size. The FAU-type zeolite with average particle size 0.4$\mu$m and BET surface area 838 $m^2$/g was obtained from starting materials of liquid sodium silicate, sodium aluminate, and sodium hydroxide with two step preparation of mixture gel, aging of the mixture gels in two steps, which effectively reduced the crystallization time and particle size.

Influence of Preparation Conditions on the Formation of Copper (II) Architectures with Pyrazine-2,3,5-tricarboxylic Acid

  • Wang, Feng-Qin;Lin, Shu;Guo, Ming-Lin;Xu, Jun-Jian;Wang, Xiao-Qing;Zhao, Yong-Nan
    • Bulletin of the Korean Chemical Society
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    • v.32 no.7
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    • pp.2351-2357
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    • 2011
  • Three new metal-organic copper(II) complexes, $[Cu(H_2PZTC)_2]_n{\cdot}2nH_2O$ (1), $[Cu(HPZTC){\cdot}2H_2O]_n{\cdot}2nH_2O$ (2), and $Cu_2[(PZHD)(OH)(H_2O)_2]_n$ (3) ($H_3PZTC$ = pyrazine-2,3,5-tricarboxylic acid, $PZHD^{3-}$ = 2-hydroxypyrazine-3,5-dicarboxylate), have been synthesized from $Cu(II)/H_3PZTC$ system under different synthetic conditions, and characterized by single-crystal X-ray diffraction, elemental analysis, IR spectroscopy and thermogravimetric analysis. In complexes 1 and 2, $H_3PZTC$ ligands loose one and two protons, which were transformed into $H_2PZTC^-$ anion and $HPZTC^{2-}$ dianion under different preparation condition, respectively. Furthermore, two ligands coordinate with Cu(II) cations in different modes, leading to the formation of the different chain structures. In complex 3, $H_3PZTC$ ligand was converted into a new ligand-PZHD by in situ decarboxylation and hydroxylation under a higher pH value than that for complexes 1 and 2. PZHD ligands link the Cu(II) cations to form a 2D layer structure. These results demonstrate that the preparation conditions, including pH value and reaction temperature etc, play an important role in the construction of complexes based on $H_3PZTC$ ligand.

Physicochemical Property Changes of Whole Soymilk Dependent on Hydrolysis Conditions (전두유의 가수분해조건에 따른 이화학적 특성 변화)

  • Jang, Se-Young;Gu, Young-Ah;Park, Nan-Young;Kim, In-Sun;Jeong, Yong-Jin
    • Food Science and Preservation
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    • v.14 no.4
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    • pp.394-399
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    • 2007
  • In this study, the characteristic qualities of whole soymilk were examined based on differing hydrolysis condition. The results showed that as the concentration of enzyme preparation(KMF-G) increase, $^{\circ}Brix$, calcium-binding capacity, and the content of free amino acid components also increased. Additionally SDS-PAGE analysis revealed a similar pattern of in the molecular weight of proteins at enzyme preparation concentration 0.20 and 0.35%(w/w). The quality of whole soymilk hydrolysate was shown to be best at a enzyme preparation(KMF-G) concentration of 0.20%(w/w) and hydrolysis time of 60 min. When sterilized at 115, 130 and $145\;^{\circ}C$ for 15 sec each the change in whole soymilk quality was not substantial. Based on the above results, a 0.20%(w/w) enzyme preparation(KMF-G) concentration and 60 mim hydrolysis time was determined to be the optimal hydrolysis condition for whole soymilk. It is anticipated that soymilk hydrolysis will a food material that is diverse in its application and uses.

Preference survey on the development of a bath preparation used by Zizania latifolia (고장초(Zizania latifolia)를 이용한 입욕제 개발제품의 선호도 조사)

  • Oh, Pyung-Il;Hong, Seung-Hui;Lee, Han-Chun;Moon, Kyung-Rye;Lee, Mi-Ja
    • The Journal of the Korea institute of electronic communication sciences
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    • v.8 no.7
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    • pp.1111-1120
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    • 2013
  • Zizania latifola has used for folk medicine in Korea. It is effective in treating skin trouble and sensitivity skins. The purpose of this study was to develop high valuable types of bath preparation of Zizania latifolia. The natural materials were manufactured by the mixed ratio of Zizania latifolia. Product was manufactured by the mixed ratio of Zizania latifolia and 3 natural materials. Green tea was highest in sensory evaluation as similar with Zizania latifolia. optimum condition of mixed ratio was adaptive 50% Houttuynia cordata, 30% green tea with 20% Artemisia vularis. Product's sensory evaluation was showed best in mixing 40% and Zizania latifolia extract 60%. There were optimal condition for manufacturing of cleansing. Therefore, The development of a bath preparation used by Zizania latifolia is very useful for manufacturing cleansing. We suggest that it help for improve skin trouble and make healthy skin.

A Study on the Methodology of Chromosome Preparation from Blood Culture (혈액세포를 이용한 염색체 분리 분석에 관한 방법적 고찰)

  • Sohn, S.H.;Chung, K.M.
    • Clinical and Experimental Reproductive Medicine
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    • v.21 no.2
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    • pp.207-214
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    • 1994
  • This study was carried out to develop the methodology of chromosome preparation from blood cultures in mammals which included human, mouse, cattle and pig. For karyotyping, 0.5-5.0ml of peripheral blood were collected and cultured. The satisfactory results were obtained from macroculture and microculture in all species. In culture, the patterns of cell growth were no difference among media except serum concentration and mitogen supplement. The presence of mitogen and fetal bovine serum in medium significantly affected the mitotic index. The optimal culture condition was 37$^{\circ}C$ for 3 days. And the concentration of colcemid and reincubation time also affected the chromosome morphology. In harvest, chromosome patterns were mainly affected on hypotonic treatment which included treated time and temperature, dropwise of fixative solution, and drying after slide preparation.

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The Heat Treatment Characterization of Plasma Sprayed Alumina Coatings (플라즈마 용사법에 의한 $Al_2$O$_3$ 피복층의 열처리효과에 관한 연구)

  • 오익현;김한산;김수식
    • Journal of Surface Science and Engineering
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    • v.27 no.3
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    • pp.134-142
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    • 1994
  • $Al_2O_3$coatings on mild steel substrate by plasma spray process were produced to evaluate microstructural characterization and mechanical properties. As-coated $Al_2O_3$coating samplessd were subjected to two heat treat-ment conditions : ⅰ) annealing under vacuum circumstance, ⅱ) hot press treated condition. The two heat treat-ed coatings were investigated in terms of microhardness, adhesion strength, wear resistance, porosity forma-tion, and microstructures. In the case of the coatings which were subject to preparation step ⅰ, the porosity in the coating was decreased with the increase of temperature ($700^{\circ}C$-$1100^{\circ}C$), and the wear resistance, microhardnesss and adhesion strength were increased with the increase of temperature. On the other hand, in the case of the coatings which were subject to preparation step ⅱ, wear resistance and adhesion strength were improved with the increase of temperature and pressure. Experimental measurements of coatings which were produced by both preparation conditions were enhanced compare to those of as-coated coatings.

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A Study on Bending Fatigue Strength of One Side Fillet Welded T-Joint by SM 490A steel (Sm 490A강으로 제작된 T형 편면용접이음재의 굽힘피로강동에 관한 연구)

  • 엄동석;강성원;이태훈;이해우;조수형
    • Journal of Welding and Joining
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    • v.16 no.5
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    • pp.134-141
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    • 1998
  • In this study, a fillet size for bending fatigue strength of one side fillet welded T-joint, used in box type girder and other welding structure, was investigated by bending fatigue test with or without edge preparation and burn through, with variation of joint shape. As a result, the following conclusions were obtained. (1) In one side fillet welded T-joint, the larger the leg length, the greater the bending fatigue strength. The increase in bending fatigue strength. (2) One side filet welded T-joint with edge preparation showed higher bending fatigue strength than that with twofold-large leg length and without edge preparation. (3) In one side fillet welded T-joint without edge preparation, both manual welding and automatic welding were carried out with same condition. In this case, automatic welding shoed deeper penetration and more increased horizontal leg length than manual welding, so that automatic welding offers grater bending fatigue strength. (4) For one side fillet welded T-joint without edge preparation, the ratio(h/t) of the leg length (h) and the main plate thickness (t) in which toe crack can occur was 1.2 over. (5) In one side fillet welded T-joint with edge preparation, the burn through led to reduced bending fatigue strength. However, this bending fatigue strength was higher than that of one side fillet welded T-joint without edge preparation and with a larger leg length.

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Analysis of Plant Hormones using GC-MS (GC-MS를 이용한 식물홀몬 분석)

  • 조광연
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.34 no.s01
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    • pp.26-32
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    • 1989
  • The analytic principles of GC and MS were explained in relation to plant hormone analyses and the characteristics of two instruments were compared. The selection of column, condition of measurement and the method of ionization to get a good spectrum were also briefly described. Finally, the pre-treatment of sample by solvent extraction method to remove the unnecessary part of sample and the synthetic method, especially reagents and reaction condition, for the preparation of ether or ester derivative which can be easily vaporized in GC were explained.

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