• 제목/요약/키워드: Heat treatments

검색결과 1,086건 처리시간 0.035초

고분자전해필 연료전지 분리판용 316 스테인리스강의 전기전도도에 미치는 Nb, Ti 첨가 및 표면처리 효과 (Effects of Nb and Ti Addition and Surface Treatments on the Electrical Conductivity of 316 Stainless Steel as Bipolar Plates for PEMFC)

  • 이석현;김정헌;김민철;천동현;위당문
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2006년도 추계학술대회
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    • pp.324-324
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    • 2006
  • Nb and Ti were added to 316 stainless steel, and then heat-treatments and surface treatments were performed on the 316 stainless steel and the Nb- and Ti-added alloys. All samples indicated enhanced electrical conductivity after surface treatments, whereas they showed low electrical conductivity before surface treatments due to the existence of non-conductive passive film on the alloy surface. In particular, the Hb- and Ti-added alloys showed remarkable enhancement of electrical conductivity compared to the original alloy, 316 stainless steel. Surface characterization revealed that small carbide particles formed on the alloy surface after surface treatments, while the alloys indicated flat surface structure before surface treatments. $Cr_{23}C_6$ mainly formed on the 316 stainless steel, and NbC and TiC mainly formed on the Nb- and Ti-added alloys, respectively. We attribute the enhanced electrical conductivity after surface treatments to the formation of these carbide particles, possibly acting as a means of electro-conductive channel through the passive film. Furthermore, NbC and TiC are supposed to be more effective carbides than $Cr_{23}C_6$ as electro-conductive channels of stainless steel

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Effects of Dietary Heat Extruded Soybean Meal and Protected Fat Supplement on the Production, Blood and Ruminal Characteristics of Holstein Cows

  • Chen, Kuen-Jaw;Jan, Der-Fang;Chiou, Peter Wen-Shyg;Yang, Der-Wei
    • Asian-Australasian Journal of Animal Sciences
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    • 제15권6호
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    • pp.821-827
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    • 2002
  • The purpose of this study was to evaluate the effect of protected fat and heat-extruded soybean meal on the lactation performance of Holstein cows. Twenty-four cows, consisting of 20 lactating cows and 4 rumen-fistulated dry cows, were randomly allocated into four groups with 5 lactating cows and 1 fistulated cow in each group. A replicated 4${\times}$4 Latin square design with four 21 day periods, including 14 days of adaptation and 7 collection days within each period was employed. The experiment was a 2${\times}$2 arrangement, with or without heat-extruded soybean meal and protected fat inclusion. The dietary treatments consisted of supplements of (a) soybean meal (the control), (b) heat-extruded soybean meal, (c) protected fat, and (d) heat-extruded soybean meal and protected fat. The results showed that there were no significant differences in feed intake, milk yield, milk protein content, milk lactose content and body weight change between the dietary treatments. However, cows supplemented with protected fat showed a significantly increased (p<0.05) milk fat yield, 3.5% FCM and total solid yield. The increase in undegradable intake protein (UIP) via heat extruded soybean meal supplement significantly decreased the urea nitrogen concentration in the blood (p<0.05). Dietary fat inclusion significantly increased the blood cholesterol concentration (p<0.01) and decreased the ruminal pH value (p<0.01). Increased dietary UIP significantly decreased the ammonia nitrogen concentration in the rumen (p<0.01), but did not significantly influence the pH and VFA molar percentage in the rumen. It appears that dietary protected fat inclusion could improve milk fat and solid content. Increased dietary undegradable intake protein through heat extruded soybean meal did not improve milk yield. But it could alleviate the adverse effect of decreased milk protein due to dietary fat supplementation. Increased UIP could also decrease the ammonia nitrogen concentration in the rumen and plasma urea nitrogen concentration in the blood.

흰쥐의 실험적 위궤양에 대한 고백반, 적석지, 해표초의 효과 (Effects of heat-treated acumen, halloysitum rubrum and os sepiae in experimentally induced stomach ulcer in rats)

  • 이내경;윤효인;박승춘;박종일;조명행
    • Biomolecules & Therapeutics
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    • 제5권3호
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    • pp.246-252
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    • 1997
  • This study was performed to evaluate antiulcer effects of traditional folk medicines such as heat-treated acumen, halloysitum rubrum and os sepiae against stomach ulcer induced by acetic acid in Sprague-Dawley rats. Various pharmacological parameters were utilized to compare the antiulcer effects of aforementioned drugs based on the size of ulcer lesion, pepsin activity, free and total acidity, gastric secretory volume, and 5-HT (hydxoytrytamine) content. All folk medicines and ranitidine as control drus were shown to decrease ulcer lesion size after 5-day treatments, with the order of halloysitum rubrum, os sepiae, heat-treated acumen and ranitidine. All treated drugs except os sepiae inhibited the gastric volume as compared with that in the control group. Ranitidine most significantly inhibited the gastric volume. All the experimented drugs in this study lowered the gastric acidity. Halloysitum rubrum decreased it most remarkably, followed by ranitidine, os sepiae and heat-treated alumen after 5-day treatments. All used drugs alleviated the pepsin activity as compared with the control group, os sepiae being the highest then halloysitum rubrum, heat-treated alumen and ranitidine in turn. Heat-treated alumen and halloysitum rubrum showed mucin production to the great extent, and ranitidine had slight increasing effect thereon. At the end of observation period, all drugs except ranitidine increased 5-HT contents as compared to the normal group. From the above results, we could confirm the folk medicines such as heat-treated alumen, halloysitum rubrum and os sepiae have not only remarkable antiulcer effects but also preventing effects for the stomach ulcer recurrence, which suggest the experimented folk medicines could be developed as new antiulcer agents.

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The Production of Anti-cancer Substances by in vitro Grown Cultures of Panax ginseng C.A. Meyer

  • Yang, Deok-Chun;Park, Kyung-Hwa;Kim, Yong-Hae;Yoon, Eui-Soo;Kang, Tae-Jin;Park, Kwang-Tae
    • 한국자원식물학회:학술대회논문집
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    • 한국자원식물학회 1999년도 The 6th International Symposium on the Development of Anti-Cancer Resource from Plants
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    • pp.46-57
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    • 1999
  • Ginseng(Panax ginseng C.A. Meyer) is important medicinal plant but requires 4-year cultivation for root harvest because of slow growth. In contrast, ginseng callus and hairy roots grow vigorously and may Produce the same or more biologically active compounds for human health than natural ginseng roots. Therefore, ginseng callus and hairy roots can be used for commercial purposes. Polyacetylene, one of anti-cancer compounds in ginseng, was not detected in the callus cultured on the medium containing 2, 4-B, but cells derived from the callus growth was excellent, The ginseng calli cultured on the medium containing 2mg11 CPA and 0.05mg/1 BA was grown vigorously and produced panaxydol, one of ginseng polyacetylene. The biosynthesis of polyacetylene in callus was not affected by addition of NAA and sucrose in media. The SH medium was better than the MS medium for ginseng callus growth and biosynthesis of panaxydol. Another ginseng anti-cancer compounds, ginsenoside-Rg$_3$, Rh$_1$and Rh$_2$ were detected in ginseng hairy roots by heat treatment. Those of Panax ginseng were obtained after root disks of three-year old roots were infected with Agrobacterium rhizogenes Rl000 $A_4$T in dark condition after one month of culture. The optimum growth of hairy roots was achieved in the culture of 1/2 MS liquid medium in dark(22$^{\circ}C$) under 60 rpm gyratory shaking. Hairy roots grew well in 5 ι Erlenmeyer flasks, 1ι roller drums, 10ι jar-fermenters, and especially in 20ι air-lift .culture vessels. All heat treatments had remarkably different ginsenoside contents. Eleven ginsenosides were determined in heat treatment, eight in freeze dried hairy roots. Contents of ginsenoside-Rbl , Rb2, Rc, Rd. Re, Rf, and Rg$_1$tested in all heat treatments were less than those of freeze dried hairy roots. Contents of glnsenoside-Rg$_2$ in heat treatment for 1 hour at 105$^{\circ}C$ was 4.92mg/g dry wt, 3.9 times higher than 1.27 mg/g dry wt of freeze dried hairy roots. The optimum condition of heat treatment for the production of ginsenoside-Rg$_3$and Rhl was 2 hours at 105$^{\circ}C$, and ginsenoside content was 2.58mg/g dry wt and 3.62mg/g dry wt, respectively. The production of ginsenoside-Rh2 was the highest in heat treatment for 2 hours at 105$^{\circ}C$ among treatments examined, and ginsenoside-Rh$_2$content was 1.08mg/g dry wt.

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수족한(手足汗)의 원인(原因)과 치료법(治療法)에 대한 동(東).서의학적(西醫學的) 고찰(考察) (A Comparative Study of the Oriental and the Occidental Medical Literature on the Etiologies & Treatments for Palmoplantar Hyperhidrosis)

  • 고영철;신조영
    • 대한한방내과학회지
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    • 제18권2호
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    • pp.268-295
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    • 1997
  • Sweating is natural phenomenon necessary for the regulation of an individual's body-temperature. The secretion of sweat is mediated by a portion of our vegetative nervous system(the sympathetic nervous system). In some people, this system is working at a very high activity level, far higher than needed to keep a constant temperature. This condition is referred to as hyperhidrosis. Especially excessive sweating of the hands and the feet is palmoplantar hyperhidrosis or volar hyperhidrosis. This is by far the most distressing condition. It was founded that the first important cause of this was emotional factor. The hands are much more exposed in social and prefessional activities than any other part of our body. Many individuals with palmoplantar hyperhidrosis are limited in their choice of proffession, because unable to manipulate materials sensitive to humidity or reluctant to shake hands; some patients arrive to the point to avoid social contact. The occidental medical treatments for palmoplantar hyperhidrosis include application of topical agents(chemical antiperspirants such as aluminum chloride), iontophoresis(treatment with electrical current), or surgery(thoracic sympathectomy). It was reported that the most effective treatment was thoracic sympathectomy. So this study was started to find the easy and effective oriental medical treatments against the occidental medical treatments through the oriental medical literature. The occidental medical idea for palmoplantar hyperhidrosis is only limited in neurologic system, so surgery is the best treatment. But the oriental medical idea for palmoplantar hyperhidrosis is much wider, so the oriental medical causes and treatments for this are able to be veriety. And the oriental medical teatment is freely in treating the patients of palmoplantar hyperhidrosis, because entire idea including pulse, facial color, mental condition, constitution and other symptom exists in the oriental medicine. The results of a bibliographic study of causes and treatments for palmoplantar are as follows; 1. The main causes of pa1moplantar hyperhidrosis are heat in the stomach, damp-heat in the spleen and the stomach, insufficiency of the spleen-qi and the stomach-qi, deficiency of the spleen-yin and the stomach-yin, and the others are the stomach-cold syndrome, stasis of blood and dyspepsia in the stomach, disorder of the liver-qi, deficiency of the heart-yin and the kidney-yin, deficiency of the heart-yang and the kidney-yang, stagnated heat in the liver and the spleen, the lung channel-heat etc. 2. The main methods of medical treatments for palmoplantar hyperhidrosis are clearing out the stomach-heat, eliminating dampness and heat in the spleen and the stomach, invigorating the spleen-qi and the stomach-qi, reinforcing the spleen-yin and the stomach-yin, warming the stomach, relaxing the liver and alleviating of mental depression and tonifying the heart and the kidney etc. 3. The main prescriptions of palmoplantar hyperhidrosis are Taesihotang, Palmultang-kakam, Samyeongbaechusan, Chongbisan, Sasammaekmundongtang, the others are Leejungtang, Hwangkikonjungtang, Seungkitang, Boyumtang, Baekhotang, Chongsimyonjayum, Moyrosan, etc. 4. Local medicine for external use are liquid after boiling alum in water for about 1 or 2 hours, liquid after boiling alum and pueraria root in water and liquid after boiling stragalus root, pueraria root, ledebouriella root and schizonepeta in water, etc. 5. The methods of acupuncture therapy include invigorating Bokyru, Yumkuk and purgating Hapkouk, or invigorating Bokyru, Kihae and purgating Hapkouk, or steadying Hapkouk, Nokung.

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견비통(肩臂痛)에 대한 문헌적(文獻的) 고찰(考察) (Consideration of Literatures on the Treatment of Pain in Shoulder and Arm Based on Oriental Medicine)

  • 신홍중;윤일지;오민석
    • 혜화의학회지
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    • 제16권1호
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    • pp.139-146
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    • 2007
  • 1. The etiological causes of Pain in Shoulder and Arm based on literatures of Oriental medicine are attack of wind-heat on the lung, wind cold, damp-heat struggle between the vital energy and pathogenic factor and six pathogenic factors And all these causes are the conception of blockage syndrome, $Q_1$ and blood stagnating in meridian system. 2. Symptoms of Pain in Shoulder and Arm based on literatures of Oriental medicine are shoulder pain, restriction of activity and radiating pain. 3. The treatments of Pain in Shoulder and Arm based on literatures of Oriental medicine are mainly composed of both medical therapy for $B_1$ syndrome due to pathogenic wind, deficiency of both $Q_1$ and blood, consumption of the liver and the spleen, and also acupuncture and moxibustion treatment by selection of acupoint. And those treatments are for treating etiology. And also there are treatments using the meridian system and Twelve Muscle Region and Ashihyeol for the purpose of treating the symptoms. 4. Acupoints such as Gyun-u, Gyun-jung, Goi-ji, Ju-ryo and Bi-no are most used in treating shoulder and arm pain based on based on literatures of Oriental medicine.

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가열처리 방법에 따른 쑥의 정유 성분 및 함량 분석 (Analyses of Essential Oil Components and Contents in Artemisia sp According to Heat Treatments)

  • 김충호
    • 한국조리학회지
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    • 제17권4호
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    • pp.273-284
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    • 2011
  • 수증기 증류법을 이용하여 약용 쑥으로부터 정유를 추출 하였다. 정유는 GC-MS를 이용하여 분석하였다. 가열처리 방법은 닦음에서 온도 $80^{\circ}C$, $110^{\circ}C$, $230^{\circ}C$, 처리 시간은 6분, 10분, 14분, 데침 $100^{\circ}C$에서 1분, 2분, 5분, oven 건조 ($50^{\circ}C$)는 5분으로 하였다. 정유함량은 대조군인 생쑥에서 가장 높았고 다음이 덖음의 낮은 온도 짧은 처리 시간에서 높게 나타났다. 가장 많이 나타난 정유 성분은 eucalyptol, cyclohexadience, phenol, terpineol, caryophyllene.이다.

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ZnO:Al 투명도전막의 열처리에 따른 전기적 및 광학적 특성 (Electrical and optical properties of ZnO:Al transparent conductive films with thermal treatments)

  • 마대영;박기철
    • 전기전자학회논문지
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    • 제24권2호
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    • pp.435-440
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    • 2020
  • 고주파 마그네트론 스퍼터링으로~500 nm 두께의 ZnO:Al막을 증착하였다. 증착된 ZnO:Al막을 100 ℃, 200 ℃, 300 ℃ 및 400 ℃에서 10시간 동안 열처리하였다. ZnO:Al막의 열처리에 따른 저항률, 캐리어 농도 및 이동도 변화를 측정하였다. XRD, FESEM 결과를 통해 열처리에 따른 ZnO:Al막의 저항률 변화 원인을 조사하였다. ZnO:Al막의 광 투과율을 측정한 후 에너지 밴드 갭, Urbach 에너지 및 굴절률을 도출하였다. ZnO:Al막의 전기적 특성 변화를 광특성과 연관지어 설명하였다.

토양 유기물 분리 처리 방법이 비친수성 오염물질 흡착에 미치는 영향

  • 정상조;챨리 월스
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2005년도 총회 및 춘계학술발표회
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    • pp.42-45
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    • 2005
  • Accurate prediction of the fate and transport of contaminants in soils and sediments is very Important to environmental risk assessment and effective remediation of contaminated soils and sediments. The fate and transport of contaminants in subsurface are affected by geosorbents, especially carbonaceous materials including black carbon. Various physical and chemical treatment methods have been developed to separate different kinds of carbonaceous materials from soils and sediments. However, the effects of these separation methods on the properties of remaining carbonaceous materials including sorption capacity and linearity are unclear. The objective of this study is to determine if the chemical and thermal treatment methods previously used to separate different carbonaceous material fractions affect the properties of carbonaceous materials including longer term sorption capacity of hydrophobic organic contaminants. The results indicate that treatments with hydrochloric acid (HCl)/hydrofluoric acid (HF), trifluoroacetic acid (TFA), sodium hydroxide (NaOH) may not affect the sorption capacity of black carbon reference materials such as char and soot, however, treatments with acid dichromate $(K_2Cr_2O_7/H_2SO_4)$ and heat $(375^{\circ}C)$ for 24 hours in sufficient of oxygen) decrease the sorption capacity of them. The results of longer term sorption isotherm indicate that 2 days might be enough for trichloroethene (TCE) to equilibrate apparently with treated black carbon reference materials. The results suggest that acid dichromate and heat treatments may not appropriate method to investigate sorption properties of black carbon in soils and sediments.

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에폭시 복합체의 유전특성에 미치는 산무수물 경화제와 후경화 열처리의 영향 (Effects of acid-anhydride hardener and postcuring heat-treatments on dielectric properties of epoxy composites)

  • 왕종배;이성일;이준웅
    • E2M - 전기 전자와 첨단 소재
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    • 제7권3호
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    • pp.187-199
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    • 1994
  • In order to find an effect of structural changes due to variation of addition ratio of anhydride hardener and postcuring herat-treatments upon electrical properties of epoxy composites, the dielectric properties over a frequency range from 30[Hz] to l[MHz] were investigated in the temperature range of 20-180[.deg. C]. From the dielectric properties, the a peaks related with glass-transition phenomena of epoxy network appeared near 130[.deg. C], the conduction loss in high temperature region above 150[.deg. C] due to thermal dissociation of hardener started off with the low frequency side and the .betha. peak concerned with contribution of movable unreacted terminal epoxy groups and curing agents in the glass states concurred with the high-frequency side below 20[.deg. C]. And an effect of an hydride hardener upon structural changes and of postcuring heat treatments upon structural stability in epoxy composites would be explained through the estimation of the distribution of relaxation times and the activation energy for a .alpha. peak according to the WLF equations.

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