• Title/Summary/Keyword: temperature reactive

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Reactive Synthesis of ZrB2-based Ultra High Temperature Ceramics

  • Liu, Hai-Tao;Zhang, Guo-Jun
    • Journal of the Korean Ceramic Society
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    • v.49 no.4
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    • pp.308-317
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    • 2012
  • Reactive processing, such as reactive hot pressing (RHP) and reactive spark plasma sintering (R-SPS), is effective densification method to prepare $ZrB_2$-based ultra high temperature ceramics (UHTCs). The present paper reviewed some typical reactive processing of $ZrB_2$-based UHTCs. All the reactions from the starting materials in the reactive processing are thermodynamically favorable, which generate enough energy and driving force for the densification of the final products under a relatively low temperature. Besides, compared with non-reactive processing, anisotropic $ZrB_2$ grains, such as $ZrB_2$ platelets, can only be obtained in the reactive processing, resulting in an improvement of the mechanical properties.

Dyeability of Cotton Fabrics Treated with Liquid Ammonia - Color strength of the dyeings with low-temperature and high-temperature reactive dyes - (액체암모니아 처리 면직물의 염색성 - 저온형과 고온형 반응성 염료에 의한 염색물의 색상강도 -)

  • 전성기;이창수;임용진;김태경
    • Textile Coloration and Finishing
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    • v.16 no.2
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    • pp.1-7
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    • 2004
  • The dyeability of cotton fabrics treated with liquid ammonia was investigated using low-temperature and high-temperature reactive dyes. From the results of dyeing rates of direct dye, the inversion time was shown at 600 hours at $40^{\circ}C$, and however it was shown at 10 minutes at $80^{\circ}C$. This was applied to reactive dyeings. In the low-temperature reactive dyes, the color strength of the fabrics treated with liquid ammonia was lower than that of mercerized fabrics. By contrast, in the high-temperature reactive dyes, the color strength of the fabrics treated with liquid ammonia was higher than that of mercerized one.

Experimental Study on the Basic Properties of Concrete Composition Mixed with Pigments Having been Color Changed by the Temperature (감온성 안료의 혼입에 따른 온도반응 색변환 콘크리트의 기초물성에 관한 실험적 연구)

  • Lee, Joo-Hun;Park, Yong-Kyu;Jeon, In-Ki;Yoon, Ki-Won
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2009.11a
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    • pp.149-152
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    • 2009
  • Recent trends show an increased usage of 'colored concrete', a inorganic pigmented concrete mix, especially in smalll to large scale buildings. However, due to lack of varieties, current usage of colored concrete is limited to the one or two simple color of the time in construction work. so, this study is to investigate the properties of concrete adding temperature reactive pigment. The results of the experiment, the basic material characteristics of concrete such as of compressive strength and slump is affected by the amount rate of adding the temperature reactive pigment. And, it showed the excellent color expression and changing with temperature reactive pigment.

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Analysis on Temperature Profiles upon High Speed Impact of Reactive Structural Materials (반응성구조체의 고속충돌에 따른 온도분포 분석)

  • Jung, Sang-Hyun;Cho, Soo Gyeong;Bae, Gwang Tae;Lee, Kibong
    • Journal of the Korea Institute of Military Science and Technology
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    • v.20 no.5
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    • pp.654-664
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    • 2017
  • The temperature profiles upon high speed impact of reactive structural materials were analyzed. A two color pyrometer, which included high-speed camera, spectral splitter, and band pass filters, was utilized to measure transient temperature profiles during and after reactive metal samples impacted into steel plate with velocities of 1600~1700 m/s. The spatial temperature distribution was analyzed from the ratio of spectral radiances at two different wavelength in infrared zone, i.e. 700 and 900 nm. The measured temperatures were calibrated with black body source. Two different types of metal samples, namely aluminum and nickel, were employed to understand reaction behavior upon the impact of samples in ambient condition. According to our experiments, the Ni sample appeared to barely react with ambient air producing an instant small fireball, while Al sample reacts violently with air generating a relatively prolong fireball.

Application of Wool Dyes for Hair Dyeing (양모용 염료의 염모제 적용성 연구)

  • Chae, Da Eun;Lee, Eunkyo;Kim, Yewon;Seo, Dongwan;Oh, Nahyun;Koh, Joonseok
    • Textile Coloration and Finishing
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    • v.32 no.1
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    • pp.27-37
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    • 2020
  • Low temperature dyeing properties of wool with reactive dyes and acid dyes were investigated for the feasibility study of their application to hair dyeing. The low temperature(30℃, 40℃) dyeing achieved light depth of shade in wool dyeing and reactive dyeing exhibited relatively higher color strength and chroma values than acid dyeing. Leveling agent slightly improved the levelness of the wool dyeing and the leveling properties of dyed wool at low temperature were good to excellent, irrespective of the dyes applied. Color loss during the repeated shampooing was in the range of 9.6~22.2% for reactive dyes and -7.4~31.5% for acid dyes and in some cases, the color fastness to shampooing was reasonable level. The overall experimental results showed that the application of low temperature wool reactive dyeing to hair dyeing is sufficiently feasible in terms of dyeability and color fastness to shampooing.

Effects of Deposition Temperature on the Properties of InN Thin Films Grown by Radio-frequency Reactive Magnetron Sputtering (증착 온도가 RF 반응성 마그네트론 스퍼터링법으로 성장된 InN 박막의 특성에 미치는 영향)

  • Cho, Shin-Ho
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.22 no.10
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    • pp.808-813
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    • 2009
  • Indium nitride thin films were deposited by the radio-frequency reactive magnetron sputtering method. The indium target was sputtered by the mixture flow ratio of $N_2$ to Ar, 9:1. The effects of growth temperature on the structural, optical, and electrical properties of the films were investigated. With increasing the growth temperature, the crystallinity of the films was improved, and the crystalline size was increased. The energy bandgap for the film grown at $25^{\circ}C$ was 3.63 eV, and the bandgap showed an increasing tendency on the growth temperature. The carrier concentration, Hall mobility and electrical resistivity of the films depended significantly on the growth temperature and the maximum Hall mobility of $32.3\;cm^2$/Vsec was observed for the film grown at $400^{\circ}C$.

A Study on Dyeing of Silk with Different Reactive Dyes (반응성염료의 반응기에 따른 견섬유염색에 관한 연구)

  • 정지인;류효선
    • Textile Coloration and Finishing
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    • v.4 no.4
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    • pp.73-80
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    • 1992
  • The influence of four types of reactive dyes that are different in reactive group on silk fabric were investigated at three different temperatures, 5$0^{\circ}C$, 7$0^{\circ}C$, 9$0^{\circ}C$ and the pH range from 7.0 to 11.0. The amount of absorption and fixation showed the optimum condition. The damage of silk during dyeing was determined by the change of physical properties. The results are given as follows: 1. The amount of dye fixed on fabrics at constant pH varied upon the reactivity of dyes. The affinity of dyes for silk fabrics were in order of Lanasol>Procion>Remazol>Cibacron. 2. The percentage of dye fixation on fabrics showed different tendency with temperature. The dye fixation of Cibacron and Procion was decreased above 7$0^{\circ}C$ because of the influence of hydrolysis. The dye fixation of Lanasol and Remazol was increased with the increase of temperature. This showed that temperature did not affect on hydrolysis. 3. The tensile strength of dyed fabric decreased with increasing pH and temperature owing to high temperature and alkaline damage on silk fabric. 4. The optimum conditions of dyeing silk with reactive dyes were as follows: Cibacron -7$0^{\circ}C$, pH 9.0, Procion-5$0^{\circ}C$, pH 7.0, Remazol-5$0^{\circ}C$, pH 8.0, and Lanasol-9$0^{\circ}C$, pH 9.0.

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Carbon Deposition on Nickel Catalyst for Pre-reforming of Propane (니켈 촉매를 이용한 프로판 예개질 반응의 탄소침적에 대한 연구)

  • Kim, Sun-Young;Bae, Joong-Myeon
    • 한국신재생에너지학회:학술대회논문집
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    • 2008.05a
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    • pp.487-490
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    • 2008
  • Temperature programmed oxidation (TPO) is used to characterize coke species deposited on commercial nickel catalyst, C11-PR during propane pre-reforming. Propane pre-reforming performed under various condition, S/C from 1.5 to 2.5 and temperature from $350^{\circ}C$ to $450^{\circ}C$. There are three kinds of coke species detected by TPO: (i) reactive coke, (ii) coke deposited on metal site and (iii) coke deposited on acid support. Coke deposited on metal and support are minimized although reactive coke is generated at temperature of $400^{\circ}C$ and S/C of 2.0. Reactive coke is expected to remove easily below temperature of $200^{\circ}C$. Therefore, optimized pre-reforming condition for propane is $400^{\circ}C$ and S/C of 2.0.

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Nonlinear Model Based Control of Two-Product Reactive Distillation Column

  • Lee, In-Beum;Han, Myung-Wan
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.50.3-50
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    • 2001
  • Nonlinear feedback control scheme for reactive distillation column has been proposed. The proposed control scheme is derived in the framework of Nonlinear Internal Model Control. The product compositions and liquid and vapor flow rates in sections of the reactive distillation column are estimated from selected tray temperature measurements by an observer. The control scheme is applied to example reactive distillation column in which two products are produced in a single column and the reversible reaction A + B = C + D occurs. The relative volatilities are favorable for reactive distillation so that the reactants are intermediated boilers between the light product C and the heavy product D. Ideal physical properties, kinetics and ...

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A Study on the Decolorization of Reactive Dyes by Using Ozone Treatment (오존에 의한 반응성 염료의 탈색에 관한 연구)

  • Lee, Mun-Soo
    • The Journal of Natural Sciences
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    • v.9 no.1
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    • pp.9-17
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    • 1997
  • We studied on the decoloring efficiency of a dying and finishing industrial wastewater containing reactive dyes in the ozone treatment system. The wastewater containing reactive dyes improved the decolorization by the ozone oxidation. In order to determine the optical conditions for ozonation, various operation factors such as initial wastewater concentrations, pH, temperature, and ozone dose were evaluated. Ozone utilization rate was improved in general with the increase of initial concentration of wastewater. And the decolorization speed or reactive dyes was more decreased in deep color of blue series than in light color such as yellow series. The colorization of wastewater containing reactive dyes was changed step through midle color depending upon increasing of ozone treated time. The efficiency of decolorization for wastewater was improved with the pH increased and the temperature of ozone treatment system decreased.

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