• Title/Summary/Keyword: the thermal treatment time

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Effects on the Esophageal Rewarmer for Repairing in Rabbits with Profound Hypothermia (토끼의 초저체온증 회복을 위한 식도가온법에 관한 연구)

  • 정병현;이병한
    • Journal of Veterinary Clinics
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    • v.17 no.1
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    • pp.138-144
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    • 2000
  • The studies were carried out to investigate the effects of esophageal thermal tube for rewarming in the hypothermia in rabbits. Thiry-one rabbits were continuously cooled with femoral arterio-venous bypass circulation to 25.0${\pm}$0.3$^{\circ}C$(profound hypothermia) of rectal temperature. The experiment was consisted with 3 esophageal thermal tube groups perfused with circulation water at 38${\pm}$1$^{\circ}C$(low, n=12), 42${\pm}$1$^{\circ}C$(medium, n=12), and 45${\pm}$1$^{\circ}C$(high, n=7). Esophageal thermla tube specially constructed double-lumen esophageal tube with circulating warm water at respective htermal grade. With this device, rewarming of the rabbits as follows; High-esophageal thermal tube group(45${\pm}$1$^{\circ}C$)had a more effect on mean arterial pressure(MAP), heart rate(HR), esophageal temperature, and rectal temperature than others groups, but the circulation water at 45$\pm$1$^{\circ}C$ may cause thermal injuries in the esophagus because esophageal temperature increased to 41.1$^{\circ}C$. Medium-esophageal thermal tube group(42${\pm}$1$^{\circ}C$) had a more effect on RR than others groups, but the circulation water at 42${\pm}$1$^{\circ}C$ may also cause thermal injuries in the esophagus if the temperature exceeds 42$^{\circ}C$ for an extended period of time because its esophageal temperature increased to 39.4$^{\circ}C$. Low-esophageal thermal tube group(38${\pm}$1$^{\circ}C$) had a more effect on MAP, RR, and esophageal temperature than others groups. In conclusion, rewarming of the central core in the treatment of profound hypothermia using the esophageal thermal tube perfused with circulation water at 38${\pm}$1$^{\circ}C$ appears to be a ideal alternative safety zone of the temperature of circulation water avoiding thermal injury in esophagus causing by out of order or lower precise thermostat of water bath to that of others groups.

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Effect of Aging Heat Treatment on the Mechanical Properties in Inconel 718 Alloy (Inconel 718 합금의 시효열처리가 기계적 성질에 미치는 영향)

  • Kang, Hee Jae;Kim, Jung Min;Jee, Sung Hwan;Sung, Jie Hyun;Kim, Young Hee;Sung, Jang Hyun;Jeon, Eon Chan
    • Journal of the Korean Society for Precision Engineering
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    • v.30 no.3
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    • pp.271-277
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    • 2013
  • Inconel 718 super alloy was aging heat treated at the temperature range from $675^{\circ}C$ to $785^{\circ}C$ for 5~40 hours after solution annealing at $1025^{\circ}C$ for 1 hour. The aging treated specimens were investigated microstructure, mechanical properties and thermal expansion/contraction. Precipitates appeared for a long time aging treatment were niobium carbide and also ${\gamma}^{\prime}$ phase. For the aging treatment time of 10 hours, the changes in strength and hardness with increasing aging treatment temperature showed the maximum value at the temperature of $725^{\circ}C$. This maximum value is to be related with the precipitation of ${\gamma}^{\prime}$ and ${\gamma}^{{\prime}{\prime}}$ phases. The decrease in strength, elongation and hardness during long time aging at $725^{\circ}C$ were thought to be induced from the coarsening of the grain size and the transformation of ${\gamma}^{{\prime}{\prime}}$ phase to ${\gamma}^{\prime}$ phase. For the specimens treated for 10 hours, impact energy showed constant value of ~105 J with increasing the aging temperature, however this value continuously decreased with elapsing time at the aging temperature of $725^{\circ}C$. It was found that the decrease in impact value was induced from the coarsening of grain size and the carbide coarsening. The coefficient of thermal expansion of aging treated Inconel 718 alloy increased with raising test temperature, and the coefficient was appeared $11.57{\sim}12.09{\mu}m/m{\cdot}^{\circ}C$ and $14.28{\sim}14.39{\mu}m/m{\cdot}^{\circ}C$, respectively, after heating to $150^{\circ}C$ and $450^{\circ}C$.

Effects of Hydrogen Plasma Treatment of the Underlying TaSiN Film Surface on the Copper Nucleation in Copper MOCVD

  • Park, Hyun-Ah;Lim, Jong-Min;Lee, Chong-Mu
    • Journal of the Korean Ceramic Society
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    • v.41 no.6
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    • pp.435-438
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    • 2004
  • MOCVD is one of the major deposition techniques for Cu thin films and Ta-Si-N is one of promising barrier metal candidates for Cu with high thermal stability. Effects of hydrogen plasma pretreatment of the underlying Ta-Si-N film surface on the Cu nucleation in Cu MOCVD were investigated using scanning electron microscopy, X-ray photoelectron spectroscopy and Auger electron emission spectrometry analyses. Cu nucleation in MOCVD is enhanced as the rf-power and the plasma exposure time are increased in the hydrogen plasma pretreatment. The optimal plasma treatment process condition is the rf-power of 40 Wand the plasma exposure time of 2 min. The hydrogen gas flow rate in the hydrogen plasma pretreatment process does not affect Cu nucleation much. The mechanism through which Cu nucleation is enhanced by the hydrogen plasma pretreatment of the Ta-Si-N film surface is that the nitrogen and oxygen atoms at the Ta-Si-N film surface are effectively removed by the plasma treatment. Consequently the chemical composition was changed from Ta-Si-N(O) into Ta-Si at the Ta-Si-N film surface, which is favorable for Cu nucleation.

Anti-nociceptive Activity of Methanol Extracts from Ligularia stenocephala (곤달비 메탄올 추출물의 진통 효과)

  • Cha, Dong Seok;Jeon, Hoon
    • Korean Journal of Pharmacognosy
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    • v.44 no.1
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    • pp.70-74
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    • 2013
  • Ligularia stenocephala has been widely used as a traditional medicine for the treatment of lots of diseases such as asthma, arthritis, and jaundice. In this study, we evaluated the anti-nocicepitve activities of methanolic extract of L. stenocephala (MLS) using various pain models including thermal nociception as well as chemical nociception methods. MLS showed significant increase in latency time in the tail immersion test and hot-plate test. In addition, the number of acetic acid-induced abdominal constrictions was decreased by MLS. MLS also attenuated paw licking time in the formalin test. The combination test using naloxone revealed that the anti-nociceptive properties of MLS was not associated with opioid receptor activation. The present results demonstrate that MLS may possibly used as valuable analgesic agent for the treatment of nociceptive pain.

Surface Charcterization of plasma-treated silicone insulating materials (플라즈마 처리된 실리콘 절연재의 표면 특성화)

  • Song, J.Y.;Huh, C.S.;Youn, B.H.;Lee, T.H.;Yoo, H.C.;Seo, Y.J.;Lee, K.T.;Kim, N.R.;Lee, U.H.
    • Proceedings of the KIEE Conference
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    • 2002.11a
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    • pp.176-178
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    • 2002
  • Surface states of silicone polymer treated by plasma were investigated by the analysis by x-ray photoelectron spectroscopy(XPS) and surface voltage decay after corona charging. Plasma treatment causes the silica -like oxidative layer, which was confirmed with XPS, and lowers surface resistivity with increasing the plasma treatment time. Using the decay time constant of surface voltage, the calculated surface resistivity was compared with the value directly measured by voltage-current method using three electrodes system. A good agreement between two methods was obtained. In addition, we estimated the thermal activation energy for surface conduction, Based on our results, we could understand the relationship between surface chemical states and surface electrical properties.

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Inactivation Kinetics of Listeria innocua ATCC 33090 at Various Temperature Heating-up and Pressure Building-up Rates

  • Ahn, Ju-Hee;Balasubramaniam, V.M.
    • Food Science and Biotechnology
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    • v.16 no.2
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    • pp.255-259
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    • 2007
  • The effects of temperature heating-up rate and pressure building-up phase on the inactivation of Listeria innocua ATCC 33090 were evaluated in buffered peptone water. The number of L. innocua was reduced by 5.57 and 6.52 log CFU/mL during the nonisothermal treatment (the come-up time followed by isothermal process) and the isothermal treatment, respectively, at $60^{\circ}C$. When compared to the isothermal treatment (0.76$33.2^{\circ}C/min$ of temperature heating-rate. The effect of the combined high pressure and thermal processing on the inactivation of L. innocua increased with increasing pressure and temperature. At all temperature levels from 40 to $60^{\circ}C$ under 700 MPa, L. innocua was not detected by enrichment culture (>7 log reduction).

Alkali Treatment Effect of Kenaf Fibers on the Characteristics of Kenaf/PLA Biocomposites (Kenaf 섬유의 알칼리처리가 Kenaf/PLA 바이오복합재료의 특성에 미치는 영향)

  • Seo, Jeong Min;Cho, Donghwan;Park, Won Ho
    • Journal of Adhesion and Interface
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    • v.9 no.4
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    • pp.1-11
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    • 2008
  • In the present study, kenaf fibers were treated with sodium hydroxide using soaking and ultrasonic methods prior to biocomposite processing, respectively. The effect of alkali treatment on the kenaf-PLA interfacial adhesion and mechanical and thermal characteristics of kenaf/poly(lactic acid) biocomposites was investigated in terms of their interfacial shear strength, flexural properties, dynamic mechanical properties and thermal stability and also microscopic observations of kenaf fibers and the composite fracture surfaces. As a result, use of both soaking and ultrasonic methods for treating kenaf fiber surfaces played a role in increasing the fiber-matrix adhesion and the mechanical properties of the biocomposites. Their characteristics depended not only on the fiber surface treatment method but also on the treatment condition like alkali concentration and treatment time.

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Manufacturing and Characteristics Analysis of PU/MWNT Composite Film for Forming (발포용 PU/MWNT 복합필름의 제조와 특성분석)

  • Park, Jun-Hyeong;Kim, Jeong-Hyun;Kim, Seung-Jin
    • Textile Coloration and Finishing
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    • v.22 no.4
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    • pp.362-372
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    • 2010
  • This paper surveys the physical properties of the multiwall carbon nanotube (MWNT) and polyurethane composite film for improvement of mechanical properties and electrical characteristics. The modification of MWNT was carried out by acid treatment with nitric and sulphuric acid mixed solution, and then followed by thermal treatment for enhancing MWNT dispersion with polyurethane. This modified MWNT was mixed with polyurethane by changing the loading content of MWNT and dispersion time under the dimethylformamide solution in the ultrasonic wave apparatus. Various physical characteristics of the modified PU/MWNT films were measured and analyzed in terms of the loading content and dispersion time. The maximum absorbance of the PU/MWNT films were observed with the 2wt% loading at dispersion times of 2 and 24 hour, respectively. The minimum electrical volume resistivity of PU/MWNT film was shown at the loading content of 0.5wt% or more irrespective of dispersion treating time. However the optimum condition was assumed to 2wt% loading at dispersion time of 2 hours by assessing the surface profile of the film using video microscope. The breaking stress and strain of the PU/MWNT film decreased with increasing loading content, but no change of physical properties was shown with increasing in dispersion time.

RTA Post-treatment of Thermal T${a_2}{O_5}$ Thin Films (열산화 T${a_2}{O_5}$박막에 미치는 RTA후처리의 영향)

  • Mun, Hwan-Seong;Lee, Jae-Seok;Han, Seong-Uk;Park, Sang-Gyun;Yang, Seung-Ji;Lee, Jae-Cheon;Park, Jong-Wan
    • Korean Journal of Materials Research
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    • v.3 no.3
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    • pp.310-315
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    • 1993
  • The effects of RT A treatment on the breakdown strengths were studied for tantalum pentoxide(${Ta_2}{O_5}$) films prepared by thermal oxidation of dc-sputtered Ta(400$\AA$) on p-type (100) Si wafer. While the relative dielectric constants of the RT A -treated specimens were not remarkably affected, the breakdown strengths of the RTA-treated specimens were greatly changed by RTA temperature and time. After the RTA treatment, the breakdown strengths of the specimens RTA-treated at the temperature below the crystallization temperature were increased to 5.4MV /cm, while those of the specimens RTA -treated at the temperature above it were decreased to 0.5MV /cm. RTA time-independence of the flat-bant voltage shift refleted that the RT A post-annealing effects on the breakdown strengths were not due to the interface reaction between the ${Ta_2}{O_5}$ layer and the Si substrate but, through the RBS analysis, to densification of the ${Ta_2}{O_5}$ films.

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Physical Properties of Liquid Ammonia Wood for Bending (휨가공을 위한 액체암모니아 처리재의 물리적 성질)

  • Kang, Ho-Yang
    • Journal of the Korean Wood Science and Technology
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    • v.31 no.1
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    • pp.52-60
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    • 2003
  • The physical properties of small hardwood and softwood specimens treated with liquid ammonia were investigated. The specimens treated for 4 or 18 hours were compared with the controls. The EMCs of the liquid ammonia treated specimens were higher than those of the controls when conditioned at the same humidities. However once oven-dried they didn't show any significant differences in EMCs. With the increase of liquid ammonia treatment time specimens shrank in radial and tangential directions, but not in longitudinal direction. As liquid ammonia treatment time increased the ultrasonic velocities of specimens decreased and their densities increased, thus their dynamic MOEs decreased. For chestnut specimens the presteamed were more plasticized than the liquid ammonia treated. Incising on the surfaces of specimens didn't improve liquid ammonia permeability in both hardwoods and softwoods. Liquid ammonia treatment was very effective for plasticizing 5 mm thick softwoods. Relative dielectric constants and thermal conductivities were measured with both liquid ammonia treated and control specimens.