• Title/Summary/Keyword: preferred density

Search Result 246, Processing Time 0.025 seconds

CHARACTERISTICS OF PLATED GOLD LAYER ON ANSI 304 STAINLESS STEEL ACCORDING TO THE VARIATION OF PRETREATMENTS AND ELECTROLYSIS CONDITIONS

  • Lee, Dong-hun;Lee, Jae-Bong
    • Journal of the Korean institute of surface engineering
    • /
    • v.32 no.3
    • /
    • pp.224-234
    • /
    • 1999
  • An attempt was made to characterize the relationship between pretreatment processes, electrolysis conditions and behaviors of the plated gold layer. In order to investigate the effect of pretreatment processes on plating, rest potential measurements of various pretreated stainless steels and a.c.-impedance spectroscopy tests were carried out in the strike plating solution. Characteristics of plated gold layers and adhesions between plated gold layers and stainless steel substrates were examined by scratching tests and micro-Vickers hardness tests. The result shows that the strike plating enhanced the adhesion of interface, the cathodic electro-activation pretreatment process improving both corrosion resistance and adhesion strength. The preferred orientations of plated gold layers were examined by the X-ray diffraction technique. As the current density increases, [111] preferred orientation of plated gold layers was found to become well developed.

  • PDF

Preferred Orientation, Microstructure, Surface Morphology and Mechanical Properties of Electrodeposited Copper Foils (電解銅薄의 優先方位, 斷面組織, 表面形態 및 機械的 性質)

  • Kim, Yoon-Keun;Lee, Dong-Nyung
    • Journal of the Korean institute of surface engineering
    • /
    • v.18 no.3
    • /
    • pp.95-104
    • /
    • 1985
  • A study has been made of preferred orientation, crose sectional microstructure, surface morphology and mechanical properties of copper foils fabricated by electrodeposition on 304 stainless steel plate from copper sulfate baths for high speed plating. The preferred orientation of the copper foils changed from the [110] to the [111] to ture with decreasing bath temperature and increasing cathode current density. The foils with the [110] texture had the field oriented texture type structure and the surface of many asperities grooved approximately perpendicular to the subtrate. A specimen with the [111]+[311] texture had the lower strength than one with the [10] texture, if they were obtained under similar electrolysis conditions.

  • PDF

Composition and microstructure of Silver-Tin alloy deposits from prophosphate bath (피로인산염욕을 사용한 은-주석 합금도금층의 조성 및 현미경 조직)

  • 예길촌;김용웅;김진수
    • Journal of the Korean institute of surface engineering
    • /
    • v.26 no.3
    • /
    • pp.143-148
    • /
    • 1993
  • Composition and microstructures of Silver-Tin alloy deposits from a pyrophosphate bath were studied under the D.C. electrolysis conditions. Cathode current efficiency and throwing power of alloy deposits de-creased with increasing current density. Tin content of Ag-Sn alloy deposits decreased noticeably with the cur-rent density and with decreasing pH. The preferred orientation of the deposits tended to change in sequence of (110)longrightarrow(111)longrightarrow(100) texture with increasing the cathode overpotential. The surface structure of alloy deposits showed the smooth surface structure with fine crystallites.

  • PDF

Productivity of the Flounder Stocking Density on the Flounder Culture Farms (넙치양식장 밀식에 따른 생산성에 관한 연구)

  • Eh, Youn-Yang
    • The Journal of Fisheries Business Administration
    • /
    • v.42 no.2
    • /
    • pp.85-96
    • /
    • 2011
  • Oliver flounder population density affect Oliver flounder growth and mortality rate. In laboratory pilot experiment, Oliver flounder growth rate is inversely proportional to stocking density. But previous study has not proved external validity. This study is aimed to analyze the effect of stocking density on the Oliver flounder culture farms in Jeju Island. In order to do this, I selected 13 farms in Jeju island as a sample. In the study, various analytical methods including productivity analysis, regression analysis, statistical analysis were conducted for 13 Oliver flounder culture farms. The result of analysis can be summarized as follows. First, in case of the Oliver flounder culture farms, Bertalanffy equation is not applicable to the Oliver flounder growth. Second, the Oliver flounder stocking density, defined as the surface area of Oliver flounder per $m^2$ of water surface area, is preferred to density definition defined as the weight of Oliver flounder per $m^2$ of water surface area on the Oliver Flounder Culture Farms case. Third, growth rate and production weight on the Oliver flounder culture farms are inversely proportional to stocking density on spearman rank correlation test. When extensive comparable biological and culture condition data become available, analysis model can be easily modified to yield more accurate results.

Study on Current Capacity of the SC Conductor for $\mu$SMES Coil ($\mu$SMES 코일용 초전도도체의 전류용량에 관한 연구)

  • Kim, H.J..;Seong, K.C.;Cho, J.W.;Jin, H.B.;Ryu, K.S.;Ryu, K.
    • Progress in Superconductivity and Cryogenics
    • /
    • v.1 no.1
    • /
    • pp.22-27
    • /
    • 1999
  • Recently, small-sized superconducting magnetic storage($\mu$SMES) coils become commercially as an energy storage device for a power conditioner. In design and fabrication of the $\mu$SMES coils, to determine optimum current capacity of the superconducting(SC) conductors is one of the important things. We thus investigated the effect of conductor's current capacity, current density, and stability on the coil's maximum stored energy density in consideration of AC losses and switching device's capacities in a power converter. The results show that the smaller current capacity of the SC conductors is preferred for the $\mu$SMES coils but can increase their induced voltage excessively.

  • PDF

The effect of pulse current electrolysis on the composition and themicrostructure of Tin-Zinc electrodeposits (주석-아연 합금도금층의 조성 및 조직에 미치는 파형전류전해의 영향)

  • 예길촌;박성진;김대영
    • Journal of the Korean institute of surface engineering
    • /
    • v.34 no.4
    • /
    • pp.303-312
    • /
    • 2001
  • Composition and microstructure of the tin-zinc alloys electroplated in gluconate bath were studied according to pulse current parameters. The cathode current efficiency increased with both the mean current density and the off-time decrease. Zinc content of the alloy deposits increased with increasing mean current density, while it decreased noticebly with increasing the off-time from 10-30ms to 100-150ms. The preferred orientation of the alloy deposits changed with the increase of peak current density in the sequence of (220)longrightarrow(220)+(420) or (220)+(420)+(321) mixed structure. The equiaxed grain size of the alloy increased with the increase of off-time and the decrease of mean current density.

  • PDF

Quality Characteristics of Cookies Different with Various Fat (유지의 종류에 따른 쿠키의 품질 특성)

  • Yoo, Seung-Seok;Jeong, Hyun-Chul
    • Journal of the East Asian Society of Dietary Life
    • /
    • v.21 no.6
    • /
    • pp.905-910
    • /
    • 2011
  • Cookies were prepared using different fat: butter, margarine, and shortening. Density, specific gravity of the dough, moisture content, spreadability, color, texture, and sensory evaluation for each cookies were conducted. Density, specific gravity and moisture content of each cookies showed the highest value with butter dough, and the lowest value with shortening dough. Spreadability of the cookie with margarine was the highest, and the cookie with butter and shortening resulted lower than that. The chromaticity 'L' and 'b' with butter cookie appeared the highest value, and margarine cookie and shortening cookie were followed that result. But chromaticity 'a' of butter cookie showed the lowest result while margarine cookie, and shortening cookie showed the highest value. Overall sensory evaluation showed high preference for butter cookie, beside margarine cookie and shortening cookie showed lower preference. Butter cookie was preferred in hardness, brittleness, color and chewiness, over margarine or shortening cookie. Flavor and sweetness with margarine cookie was preferred rather than butter cookie and shortening cookie. Softness and fatty taste of shortening cookie showed the highest result, beside margarine cookie and butter cookie showed lower result.

Microscopic Analysis of the Rock Cleavage for Jurassic Granite in Korea (주라기 화강암에 발달하는 결의 현미경학적 분석)

  • 박덕원;서용석;정교철;김영기
    • The Journal of Engineering Geology
    • /
    • v.11 no.1
    • /
    • pp.51-62
    • /
    • 2001
  • Jurassic granites of three sites, Pocheon, Geochang and Habcheon, were analysed with respect to the characteristics of the rock cleavage. Microscopic analysis for the oriented thin sections of the specimens was conducted by using the scanline survey technique to measure microcrack direction, spacing and length. The results showed that the preferred orientations of microcrack developed in quartz and feldspar arc coincident with the orientation of quarry planes. The length of microcrack is related to grain size. The length of microcrack in coarse-grained granite is longer than that in relatively fine-grained granite. In all granites, microcracks related to the preferred orientations are well developed in order of rift, grain and hardway planes in number, length and density.

  • PDF

Composition and magnetic ProPerties of CoFecu alloys according to electrolysis conditions (전해조건에 따른 CoFeCu 함금박막의 조성, 우선방위 및 자기적 특성)

  • 예길촌
    • Journal of the Korean institute of surface engineering
    • /
    • v.30 no.1
    • /
    • pp.3-12
    • /
    • 1997
  • The composition, the preferred orientation and the magnetic properties of the CoFeCu alloys electrodepositen under various electrolysis conditions in sulfate baths ware investigated. As the D.C. current density increased, the Co content in alloy electrodeposits increased, while the Cu content decreased and Fe content remained content. The effect of magnetic field up to 300 Oe on the composition of alloys was negligible. The Cu content of the alloys deposited in pulse current increased noticeably with increasing off-time, while the Co and Fe content decreased. The coercivity of the alloys with 3.5 to 7.0wt.% Cu was 1.0 to 2.0 Oe, but increased noticeably above and below that composition. The application of magnetic field during deposition decreased the coercivity of alloys. The saturation flux density of the alloys with 3.5 to 5.0wt.% Cu was relatively high in the range from 16 to 20.7Gauss. The anisotropy field(HK) of the alloys deposited under the magnetic field(50∼300 Oe) ranged from 18 to 22 Oe. The alloys had fcc structure with (111) preferred orientation, whose distribution increased a little with increasing magnetic field.

  • PDF

Mapping Soil Contamination using QGIS (QGIS를 이용한 토양오염지도 작성)

  • Kim, Ji-Young;Bae, Yong-Soo;Park, Jin-Ho;Son, Yeong-Geum;Oh, Jo-Kyo
    • Journal of Environmental Health Sciences
    • /
    • v.45 no.5
    • /
    • pp.487-496
    • /
    • 2019
  • Objective: The purpose of this study was to create soil contamination maps using QGIS (Quantum Geographic Information System) and suggest selection methods for soil pollution sources for preferential investigation in a soil contamination survey. Method: Data from soil contamination surveys over five years in Gyeonggi-do Province, South Korea (2013-2017) were used for making soil contamination maps and analyzing the density of survey points. By analyzing points exceeding the concern level of soil contamination, soil pollutant sources for priority management were identified and selection methods for preferred survey points were suggested through a study of the model area. Results: A soil contamination survey was conducted at 1,478 points over five years, with the largest number of surveys conducted in industrial complex and factory areas. Soil contamination maps for copper, zinc, nickel, lead, arsenic, fluoride, and total petroleum hydrocarbons were made, and most of the survey points were found to be below concern level 1 for soil contamination. The density of the survey points is similar to that of densely populated areas and factory areas. The analysis results of points exceeding the criteria showed that soil pollutant sources for priority management were areas where ore and scrap metals were used and stored, traffic-related facilities areas, industrial complex and factory areas, and areas associated with waste and recycling. According to the study of the model area, the preferred survey points were traffic-related facilities with 15 years or more since their construction and factories with a score of 10 or more for soil contamination risk. Conclusion: Soil contamination surveys should use GIS for even regional distribution of survey points and for the effective selection of preferred survey points. This study may be used as guidelines to select points for a soil contamination survey.