• Title/Summary/Keyword: mild heat treatment

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A Study on the Wear Characteristics and the Mechanism of KP-4M Steel for Plastic Molding (플라스틱성형용 KP-4M강의 마멸특성 및 이의 기구에 관한 연구)

  • 박흥식;전태옥;김동호
    • Tribology and Lubricants
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    • v.12 no.1
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    • pp.22-28
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    • 1996
  • This study was undertaken to investigate the dry wear characteristics and mechanism of KP-4M steel for plastic molding against SKD 61 hardened by heat treatment. The wear test was carried out under different conditions such as sliding speed, contact pressure, sliding distance, with frictional tester of pin on disc type. The wear loss on variation of sliding speed was little in lower speed range below 0.5 m/sec and in higher speed range above 1.5 m/sec,'but wear loss was high in intermediate speed range. The critical sliding speed, which showed the maximum value of specific wear rate, became lower with increased contact pressure. Increasing the contact pressure, the critical sliding distance Lcr which the wear mechanism changes from severe wear to mild wear was increased due to the decrease of oxidation reaction velocity. Through this study we suggested a model of generation and elimination process of wear debris of KP-4M steel for plastic molding.

Cobalt Oxide Nanorods Prepared by a Template-Free Method for Lithium Battery Application

  • Kim, Seong-Jun;Kim, Eun-Ji;Liu, Meilin;Shin, Heon-Cheol
    • Journal of Electrochemical Science and Technology
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    • v.7 no.3
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    • pp.206-213
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    • 2016
  • Transition metal oxide-based electrodes for lithium ion batteries have recently attracted much attention because of their high theoretical capacity. Here we report the electrochemical behavior of cobalt oxide nanorods as anodes, prepared by a template-free, one-step electrochemical deposition of cobalt nanorods, followed by an oxidation process. The as-deposited cobalt has a slightly convex columnar structure, and controlled thermal oxidation produces cobalt oxides of different Co/O ratios, while the original shape is largely preserved. As an anode in a rechargeable lithium battery, the Co/O ratio has a strong effect on initial capacity and cycling stability. In particular, the one-dimensional Co@CoxOy core shell structure obtained from a mild heat-treatment results in superior cycling stability.

Correlative Changes between Photosynthetic Activities and Chlorophyll Fluorescence in Wheat Chloroplasts Exposed to High Temperature

  • Young-Nam Hong
    • Journal of Plant Biology
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    • v.37 no.1
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    • pp.37-42
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    • 1994
  • Correlative changes between photosynthetic O2 exchange rates and room temperature Chl fluorescence were investigated in wheat (Triticum aestivum L.) chloroplasts treated with high temperature for 5 min. With increasing treatment temperature, photosynthetic O2 evolution rate mediated by PSII was decreased, showing 50% inhibition at 38$^{\circ}C$ (I50). But PSI activity measured by O2 uptake rates was stimulated as a function of increasing temperature. Dark level fluorescence (Fo)-temperature (T) analysis showed that fluorescence rising temperature (Tr), critical temperature (Tc), and peak temperature (Tp) was 38, 43, and 52$^{\circ}C$, respectively. Quenching analysis of Chl fluorescence showed that both the oxidized fraction of plastoquinone (qQ) and degree of thylakoid membrane energization (qNP) increased up to 4$0^{\circ}C$ and then declined dramatically. These results suggest that Tr is correlated with temperature showing a 50% of inhibition of photosynthesis and under mild high temperature stress, qNP is worth regarding as indicator for heat-induced damage of photosynthesis.

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A Study on the Properties of Silk and Nylon 6 Fabrics by Tannic Acid Treatment

  • Yoa, Soojin;Kim, Jongjun
    • Journal of Fashion Business
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    • v.20 no.3
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    • pp.119-132
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    • 2016
  • Weighting of silk fabrics have long been practiced in silk fabric trading based on the primary consideration of price-weight, and secondary one of quality improvement in handle, luster, and drape properties. Recent trend of practicing weighting of silk fabrics is, however, focused on the improvement of the handle, luster, drape, and other properties. During the finishing processes of synthetic fiber, nylon, comprising amide structure, include the use of tannic acid, especially in the dyeing. A multitude of studies are being implemented in terms of improving fastness to washing, fastness to light of dyed nylon product, or the light fastness of nylon 6 itself. In this study, the effects of various tannic acid treatments on the physical properties related to the handle of nylon 6 and silk fabrics are examined and reviewed. The effects of treatment condition of the tannic acid, e.g., the concentration of the aqueous tannic acid solution, treatment time, and temperature were investigated. As the concentration of the aqueous solution of tannic acid increased, the bending rigidity values of the silk and nylon 6 fabrics increased. The treated fabrics felt stiff to the touch. Within the mild conditions of bending employed in the bending measurement of KES, nylon 6 treated fabric specimen exhibited a trend of improvement of bending resiliency within the range of small bending deformation. The weight of treated fabrics have all increased. The air-permeability values decreased as the treatment concentration increased. However, the decrease tendency of air permeability values may be alleviated by adjusting the fabric count during the tentering or expanding processes, either by tension adjustment or heat treatment. Optimum conditions of the treatment for nylon 6 are 1.25% tannic acid concentration, bath temperature of $85^{\circ}C$, pH 3.1, and those for silk fabric treatment are 1.25% tannic acid concentration, bath temperature of $85^{\circ}C$, pH 3.1. The treatment conditions will lead to the improvement in the properties of fabrics for summer.

Treatment of White Line Disease by Therapeutic Shoeing in Horse (장제요법에 의한 말의 백선병 치료 1례)

  • Yang, Young-Jin;Shin, Sang-Kyung;Yun, Sung-Wook;Cho, Gil-Jae
    • Journal of Veterinary Clinics
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    • v.30 no.5
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    • pp.394-398
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    • 2013
  • An 3-year-old female Thoroughbred horse was referred with moderate lameness (3/5G) and mild heat on right hoof of forelimb. She was diagnosed with white line disease (WLD) that was included hoof wall separation by radiographic examination and hoof percussion. Treatment was carried out hoof wall resection at first, followed by disinfection of affected hoof and shod modified heart bar. On the re-examination after 4 months, we could find a results which had no lameness, gas pocket in the white line and clinical signs was improved. Subsequently, she was trained and raced after 8 months of diagnosis. So, we supposed that resection of wall and therapeutic shoeing was good for WLD including hoof separation.

Study on the division of disease and various methods of treatment appeared in the Tibetan Medicine (서장의학(西藏醫學)에 나타난 진단(診斷)과 치료(治療)에 관한 연구(硏究))

  • Chang, Eun-Young;Yoon, Chang-Ryel
    • Journal of Korean Medical classics
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    • v.18 no.2 s.29
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    • pp.45-69
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    • 2005
  • The condition contrary to the physiological conditions obtained by the normal functioning of seven constituents of the body is defined as disease. The primary causes of the disease are emotional defilements of desire, hatred and delusion. The secondary causes of diseases are seasonal climatic changes, the agency of harmful demons, and improper diet or conduct. Once a disease occurs, it brings the disfunctioning of the three humors of wind, bile, and phlegm. Therefore all the disease should be examined and determined which of theses three humors effect its nature the most. There are five main techniques of external therapy, namely bloodletting, which extract the impure blood produced by disease of heat; moxibustion, which debilitates cold diseases, medicinal compresses, fomentation, massage with ointment, and minor surgery. Among these, the former three are the mild treatment and the latter three the severe ones because of the pain the patient has to suffer during the whole procedure.

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Effect of Cold Acclimatization Training on Body Composition (추위 훈련이 신체 조성에 미치는 영향 -체중, 체지방량, 골격근량을 중심으로-)

  • Park, Joo-Hee;Choi, Jeong-Wha
    • Journal of the Korean Society of Clothing and Textiles
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    • v.35 no.7
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    • pp.713-720
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    • 2011
  • This study investigated the effect of cold acclimatization training on body composition including weight, fat mass, and muscle mass with 10 subjects (5 males and 5 females). During the 3-week acclimatization training program, they visited an artificial climate chamber ($15^{\circ}C$) 15 times and were exposed to cold environment with light clothing for 2 hours. Body composition was measured before and after cold training using bioelectric impedance analysis that was later compared by a paired t-test. In the process of thermoregulation, muscle contraction was accompanied by increased substrate metabolism for rising heat production. After cold training, the muscle mass increased and fat mass decreased significantly (p<.1, p<.05), subsequently the body composition changed. It was found that cold acclimatization training could be used as a treatment for obesity. It was suggested that further investigation on the long term effects of mild cold exposure using clothing and its potential applicability as an obesity treatment.

Changes of Functional Properties of Garlic Extracts during Storage (마늘추출액의 저장 중 기능성성분 변화)

  • Byun, Pyung-Hwa;Kim, Woo-Jung;Yoon, Suk-Kwon
    • Korean Journal of Food Science and Technology
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    • v.33 no.3
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    • pp.301-306
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    • 2001
  • An invistigation was carried out to study the effects of heat treatment of garlic and storage temperature of garlic extracts on functional properties of garlic extracts. The garlic was heated at 40, 60, 80, 100, $120^{\circ}C$ for 10 minutes and extracted with 50% ethanol. The extracts were stored at 4, 25 and $50^{\circ}C$ for 30 days, and then electron donating ability(EDA), nitrite-scavenging effects(NSE) and total thiosulfinates contents were determined. Among the functional properties, total thiosulfinates were rapidly reduced as the heating and storage temperature increased. The total thiosulfinates in the extracts were not detected for those heat-treated at 100 and $120^{\circ}C$. The EDAs were also decreased to almost half of their initial level by heat treatment of garlic at higher temperature than $80^{\circ}C$ while NSE was decreased a little. As the storage temperature increased, EDA and thiosulfinate contents decreased. Particularly the thiosulfinates were ditected none after 11 days of storage at $25^{\circ}C$ and $50^{\circ}C$. Therefore, mild heat treatment of garlic at lower temperature than $60^{\circ}C$ and storage at refrigerated condition are recommendable for preparation and storage of garlic extracts.

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A Study on the Evaluation of Mechanical Characteristics for Tailor Welded Blank Panel (TWB 판넬의 기계적특성 평가에 관한 연구)

  • Chun, Chang-Hwan;Han, Chang-Suk
    • Journal of the Korean Society for Heat Treatment
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    • v.23 no.4
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    • pp.183-190
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    • 2010
  • There are many methods to reduce the weight and the cost of the automobile body, among them, Tailor Welded Blank (TWB) is new welding method applied to body structure. It is necessary to evaluate mechanical properties of TWB structures or sheets for the application to automobile body parts. In this study, the stiffness of T-type and L-type joint structures, composite of TWB panel, which simplified two portions of side structure in automobile body were investigated. Additionally, the fatigue properties of TWB panels were obtained. Two types of welding technologies, laser and mash seam welding, were used to join mild panels with different thickness. This results are compared with conventional structures. The results are as follows: 1) The stiffness of joint structures, composite of TWB panel, is approximately 17% higher than that of conventional ones. 2) The location of welding line in TWB had a effect on the in plane bending stiffness, but not on the out of plane bending stiffness. 3) In terms of welding technology type, the mash seam welding show higher stiffness than the laser welding for in plane bending stiffness. But minimal differences in both types are revealed for out of plane bending stiffness. 4) The fatigue strength, composite of TWB panel, is lower than that of base steel. It is thought that defects in the welding zone had the action of notch in the fatigue test.

Effect of Hot Water Treatment on Storage Quality of Minimally Processed Onion (열수처리가 신선 편의가공 양파의 저장품질에 미치는 효과)

  • Hong, Seok-In;Lee, Hyun-Hee;Son, Seok-Min;Kim, Dong-Man
    • Korean Journal of Food Science and Technology
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    • v.36 no.2
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    • pp.239-245
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    • 2004
  • Storage quality of minimally processed onion as influenced by hot-water dipping was investigated to examine feasibility of mild heat treatment as efficient post-processing method. fresh onions were peeled, trimmed, and dipped in hot water at various temperatures ($50-80^{\circ}C$) for 1 min. Heat-treated onions were cooled, de-watered, packaged in low density polyethylene (LDPE) film pouches ($63\;{\mu}m\;thickness$), and stored at $10^{\circ}C$. Samples treated at higher temperatures ($70-80^{\circ}C$) showed significant increases in flesh weight loss and discoloration during storage as compared to others. Hot-water dipping remarkably reduced initial microbial load of prepeeled onions, with over 1 log cycle decrease in aerobic bacterial count. After 7 days storage, no significant differences in viable aerobe count were observed among treated and untreated samples, with both showing $10^{6}-10^{7}\;CFU/g$. For sensory attributes including discoloration, wilting, decay, and visual quality, onions treated with hot-water dipping at $60^{\circ}C$ scored highest. Results suggested hot-water dipping at specific condition as practical post-processing treatment could effectively prolong shelf life of minimally processed onion.