• 제목/요약/키워드: treating time

검색결과 1,161건 처리시간 0.034초

고온열전재료 $FeSi_2$의 변태거동 (Transformation Behaviour of High Temperature Thermoelectric $FeSi_2$)

  • 은영효;민병규;이동희
    • Applied Microscopy
    • /
    • 제25권3호
    • /
    • pp.90-98
    • /
    • 1995
  • In the Fe-Si system, a mixture of a($Fe_{2}Si_5$) - and ${\epsilon}$(FeSi)-composition powders was sintered and heat-treated subsequently at various temperatures and time to get thermoelectric ${\beta}$-phase($FeSi_2$) compacts. The different transformational sequences depending on the heat treating temperature were found through the investigation into phase transformation and microstructural development. That is, a rapid eutectoid decomposition of ${\alpha}{\to}{\beta}+Si$ occurred together with a accompanying slow reaction between the dispersed Si formed by above decomposition and the preexisted ${\epsilon}$ phase at temperatures below $830^{\circ}C$. The unreacted Si and the micropores formed due to the density change upon the transformation coarsened as heat treating time elapsed. At temperatures above $880^{\circ}C$, however, transformation was proceeded by a peritectoid reaction of ${\alpha}+{\epsilon}{\to}{\beta}$. It took at least 200min. to achieve 90% volume fracion of transformed ${\beta}$ phase, and the growth of micro-pores was also observed in this transformational sequence with prolonged heat treating time.

  • PDF

Sursulf 처리후 고주파 표면경화된 저탄소강의 경도 및 마모특성에 미치는 Sursulf 처리시간 및 고주파 경화 이송속도의 영향 (The Effect of Sursulf Treating Time and Traveling Speed during Induction Hardening on Hardness and Wear Characteristics of Low Carbon Steel Combined-Heat-Treated)

  • 노용식;김영희;이평호;신호강;이상윤
    • 열처리공학회지
    • /
    • 제2권2호
    • /
    • pp.17-26
    • /
    • 1989
  • This study has been performed to investigate into some effects of the Sursulf treatment time and the traveling speed of surface hardening treatment on the hardness and the wear characteristics by applying the combined heat treating techniques of Sursulf process followed by induction hardening treatment to mild steel. It has been shown that increasing the Sursulf treatment time increases the case depth, but both hardness and wear resistance are not considerably improved. When the combined heat treating technique of high frequency induction heating after Sursulf treatment is applied, an improvement in case depth as well as wear resistance is obtained. In particular, the hardness in diffusion zone is greatly increased due mainly to the formation of martensite and possibly lower bainite. Iron oxides formed during induction heating and subsequent water spray cooling in the outermost part of compound layer may be considered to cause some increases in hardness and wear resistance.

  • PDF

SiO$_2$ 박막을 이용한 SOI 직접접합공정 및 특성 (Processing and Characterization of a Direct Bonded SOI using SiO$_2$ Thin Film)

  • 유연혁;최두진
    • 한국세라믹학회지
    • /
    • 제36권8호
    • /
    • pp.863-870
    • /
    • 1999
  • SOI(silicon on insulafor) was fabricated through the direct bonding using (100) Si wafer and 4$^{\circ}$off (100) Si wafer to investigate the stacking faults in silicon at the Si/SiO2 oxidized and bonded interface. The treatment time of wafer surface using MSC-1 solution was varied in order to observe the effect of cleaning on bonding characteristics. As the MSC-1 treating time increased surface hydrophilicity was saturated and surface microroughness increased. A comparison of surface hydrophilicity and microroughness with MSC-1 treating time indicates that optimum surface modified condition for time was immersed in MSC-1 for 2 min. The SOI structure directly bonded using (100) Si wafer and 4$^{\circ}$off (100) Si wafer at the room temperature were annealed at 110$0^{\circ}C$ for 30 min. Then the stacking faults at the bonding and oxidation interface were examined after the debonding. The results show that there were anomalies in the gettering of the stacking faults at the bonded region.

  • PDF

질산은 처리된 실크의 환원 발색 (Cathodic Coloration of Silk Fabric Treated with Silver Nitrate)

  • 정문화;이문철
    • 한국염색가공학회지
    • /
    • 제21권2호
    • /
    • pp.14-21
    • /
    • 2009
  • In this article, silk fabric was treated with silver nitrate ($AgNO_3$) as oxidizing agent, with conditions such as concentration, and treating time, and subsequently treated with reducing agents such as sodium boron hydride ($NaBH_4$) and sodium sulfide ($Na_2S$) to obtain cathodic coloration. After coloration of silk fabric, dyeing properties (K/S value), colorfastnesses such as wash, rubbing and light, and antibacterial activity property were examined. $AgNO_3$ treating time and reducing time did not influence K/S value, whereas the pH value at alkaline region showed a high K/S value of silk fabric. The cathodic colorations of silk fabric with both of reducing agents at $30^{\circ}C$ have excellent color fastnesses. Also the high antibacterial activities were obtained by the treatment with silver nitrate even at 1% of lower concentration.

Surface Modification of Automobile Rubber by Various Plasma Treatments

  • Lee, Seung-Hun;Kim, Seock-Sam
    • KSTLE International Journal
    • /
    • 제9권1_2호
    • /
    • pp.26-30
    • /
    • 2008
  • This study examined the surface modification characteristics of NBR using sealing in automobile. Surfaces of NBR were modified by RF power Ar plasma treatment. In experiment, pressure, flux, temperature were fixed and RF bias voltage. Treatment time was changed. In friction test, we used PTFE grease. After modification, surfaces of NBR showed many grooves, hydrophilic functional groups, and lipophilic functional groups. As increasing treating voltage and time, the amount of them was increased. And wetting angle and friction coefficient was decreased with increasing treating voltage and time. However, the pattern of changing friction coefficient was not fixed.

Radiofrequency Ablation in Treating Colorectal Cancer Patients with Liver Metastases

  • Xu, Chuan;Huang, Xin-En;Lv, Peng-Hua;Wang, Shu-Xiang;Sun, Ling;Wang, Fu-An
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제16권18호
    • /
    • pp.8559-8561
    • /
    • 2016
  • Purpose: To evaluate efficacy of radiofrequency ablation (RFA) in treating colorectal cancer patients with liver metastases. Methods: During January 2010 to April 2012, 56 colorectal cancer patients with liver metastases underwent RFA. CT scans were obtained one month after RFA for all patients to evaluate tumor response. (CR+PR+SD)/n was used to count the disease control rates (DCR). Survival data of 1, 2 and 3 years were obtained from follow up. Results: Patients were followed for 10 to 40 months after RFA (mean time, $25{\pm}10months$). Median survival time was 27 months. The 1, 2, 3 year survival rate were 80.4%, 71.4%, 41%, 1 % respectively. 3-year survival time for patients with CR or PR after RFA was 68.8% and 4.3% respectively, the difference was statistically significant. The number of CR, PR, SD and PD in our study was 13, 23, 11 and 9 respectively. Conclusions: RFA could be an effective method for treating colorectal cancer patients with liver metastases, and prolong survival time, especially for metastatic lesions less than or equal to 3 cm. But this result should be confirmed by randomized controlled studies.

대전방지처리된 합성섬유의 대전성에 관한 연구 (Anti-static behavior of Synthetic fabrics treated by anti-static agents)

  • 최석철;김미성
    • 한국의류학회지
    • /
    • 제11권1호
    • /
    • pp.51-62
    • /
    • 1987
  • In this study, electrostatic behavior of polyester and nylon fabric treated with anti-static agents were investigated. The effects of the concentration of the agents and curing conditions on the electrostatic charge of the fabrics were studied. And washfastness, lightfastness and physicalproperties of the treated fabrics were also investigated. The results were as follows: 1) Polyethylene glycol alkylester was more effective in antistatic behavior than polyethylene laurylphosphate, and polyester is more effective in anti-static behavior than nylon. 2) Concentration of anti-static agents were suitable in concentration of $4\%$. 3) Glyoxal resin was more effective in anti-static behavior than melamine resin, and it was also good in the retaing anti-static behavior after treatments of lightfastness and washfastness. 4) As the condition of curing treatment, $190^{\circ}C$, 1min. for glyoxal resin and $130^{\circ}C$, 4min. for melamine resin is appropriate. 5) In comparison of anti-static behavior according to treating conditions, the simultaneous treatment was more effective than any other treatments. 6) Change of electrostatic charge of anti-static nylon cloths after treatments of lightfastness and washfastness increased greatly in above 10 laundering time and 20 fade-O-meter time. 7) In physical properties according to concentration of treating agents. decrease of physical properties scarcely appeared in concentration of treating agents $4\~5\%$.

  • PDF

각종 탈검제에 의한 식물성 기름의 탈검효과 (Degumming Effect on Vegetable oil of Degumming agent)

  • 김덕숙;안명수
    • 한국식품조리과학회지
    • /
    • 제4권1호
    • /
    • pp.27-32
    • /
    • 1988
  • 탈검제로 인산 및 초산, 구연산, 수산, 질산, 붕산 등 6종을 평지씨 기름과 대두유에 적용시킨 결과 수산을 사용하여 인산과 거의 동일한 탈검 효과를 얻을 수 있었다. 즉, 평지씨 기름에서 85% 인산 처리군과 5.10% 수산 처리군의 탄산유내의 잔류 비누물질과 인함량, 탈색유에서의 색상, 탈취유의 과산화물값, trans 지방산 함량 등은 유사한 결과를 나타내었다. 대두유에서도 동일한 결과를 얻었으므로 탈검제로서 인산 대신 수산을 사용할 수 있음을 확인하였다. 한편 85% 인산처리군과 10% 수산처리군으로부터 얻어진 폐수를 분석한 결과 특히 BOD, COD 등에서 현격한 차이를 보였으며 침전분리 및 화학처리한 결과 인산 처리군은 수산 처리군에 비하여 처리시약 요구량 및 처리시간이 각각 3배, 1.7배로 차이가 극심하였다. 따라서 이들 식물성 기름에서 인산대신 수산을 사용하여 동일한 탈검효과를 얻을 수 있었을 뿐만 아니라 폐수 처리도 개선할 수 있었다.

  • PDF

진공증착중합법에 의해 제조된 폴리이미드 박막의 플라즈마 처리에 의한 표면의 변화 (The Surface Effect of Polyimide Thin Film by Vapor Deposition Polymerization Method With Plasma Treatment)

  • 김형권;이붕주;김종택;김영봉;이덕출
    • 한국전기전자재료학회논문지
    • /
    • 제11권5호
    • /
    • pp.340-346
    • /
    • 1998
  • In this study, we intended to investigate aging effect of polyimide prepared by VDPD(vapor deposition polymerized method). The prepared polymide was treated by the oxygen and argon gas plasma. And we evaluated the polyimide treated by plasma from contact angle, surface leakage current, FT-IR and SEM. We know that the structure of polyimide at surface are changed to amide structure by plasma treating. It seems that strong energy of plasma causes breaking the molecular chin of the polyimide. And surface roughness increases with plasma treating time increased and sequentially the wettability and leakage current increases.

  • PDF

담체 변화에 따른 Labscale 바이오 필터의 성능 실험 (Operation of biofilters with different packing material)

  • D. Cho;Kwon, Sung-Hyun
    • 한국산학기술학회:학술대회논문집
    • /
    • 한국산학기술학회 2003년도 춘계학술발표논문집
    • /
    • pp.331-333
    • /
    • 2003
  • The low-pH biofiltration system in laboratory experiments demonstrate defective performance for treating H2S. When leachate pH was in the range of 1.5 to 4, the biofilters in three different media removed H2S wi th efficiencies greater than 99% while it was treated as a single contaminant. The posibility of using a single-stage low pH biofilter depends on its performance in treating VOCs. During Phase 2, a single-stage biofilter was effective for treating mixtures of H2S and toluene with toluene concentrations below 20ppm and leachate pH between 2 and 3.5. Biofiltration of xylene was ineffective when pH was lower than 1.5. The treatment system acclimated most slowly to benzene, and treatment of benzene was apparently subject to some competive inhibition from xylene and toluene. However. co-treatment was possible after some acclimation time. Xylene was not easily treated, with higher elimination capacities and no sign of competitive inhibition.

  • PDF