• 제목/요약/키워드: cold treatment

검색결과 1,650건 처리시간 0.026초

고탄소강의 구상화속도에 미치는 초기 미세조직, 냉간압연 및 온도의 영향 (Effect of Initial Microstructure, Cold Rolling and Temperature on the Spheroidization Rate of Cementite in High Carbon Steel)

  • 김준호;하태권
    • 소성∙가공
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    • 제22권3호
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    • pp.158-164
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    • 2013
  • The spheroidization behavior of cementite in a SK85 high carbon steel was investigated in this study. Fine and coarse pearlite microstructures were obtained by appropriate heat treatments according to the TTT diagram of SK85 high carbon steel. Hot rolled plates of SK85 steel were austenitized at $800^{\circ}C$ for 2 hrs and then put directly into a salt bath at either $570^{\circ}C$ or $670^{\circ}C$ to obtain a fine pearlite (FP) structure and a coarse pearlite (CP) structure, respectively. Cold rolling was subsequently conducted on those specimens with reduction ratios from 0.2 to 0.4. Spheroidization heat treatments were conducted at the subcritical temperatures of 600 and $720^{\circ}C$ for 1 to 32 hrs to elucidate the effect of initial microstructures, heat treatment temperature, and cold reduction ratios on the cementite spheroidization rate. Spheroidization proceeded with fragmentation of cementite plates, spheroidization of the cementite platelets, and coarsening consecutively. Mechanical fragmentation of cementite by cold rolling expedited the rate of spheroidization. The spheroidization rate of FP was much more rapid than that of CP and the spheriodization rate increased with increases in the cold reduction ratio.

인접 홀의 영향을 받는 홀 확장 잔류응력의 유한요소해석 (Finite Element Analysis of the Residual Stress by Cold Expansion Method under the Influence of Adjacent Holes)

  • 김철;양원호;석창성;김대진
    • 한국항공우주학회지
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    • 제31권3호
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    • pp.79-84
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    • 2003
  • 홀 확장법은 홀 주위에 압축 잔류응력층을 생성시킴으로서 균열 발생을 지연시키는 방법으로 항공산업 분야에서 널리 사용되고 있다. 홀 확장 잔류응력의 분포는 홀 확장률, 맨드럴 삽입방향, 재료 물성치 등 여러 가지 홀 확장 피라미터에 따라 달라진다. 홀 확장 잔류응력층의 정확한 파악은 항공산업의 실제 설계에 있어서 매우 중요함에도 불구하고 이에 대한 연구는 상대적으로 부족하였다. 본 연구에서는 유한요소해석을 통하여 두 개의 인전한 홀에 홀 확장법을 적용하는 경우 대한 잔류응력 분포를 구하였다. 연구 결과 두개 홀에 동시에 홀 확장을 하는 경우가 순차적으로 홀 확장으로 하는 경우보다 더 유리한 잔류응력 분포를 얻을 수 있었다.

국내논문검색서비스를 이용한 '냉증'에 관한 연구 동향 분석 (Review of cold hypersensitivity in study of Korean traditional medicine)

  • 김진환;장희재;황덕상;이진무;이창훈;이경섭;장준복
    • 대한한방체열의학회지
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    • 제9권1호
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    • pp.8-21
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    • 2011
  • Purpose : This study is to investigate the trends of study of cold hypersensitivity in Korean traditional medicine and to direct for future research. Methods : We searched for papers which had used cold hypersensitivity in korean journals. Results : 25 papers were found. 10 papers were associated with characteristics of cold hypersensitivity. 8 papers were associated with case study. 5 papers were associated with diagnosis. 2 papers were associated with research for treatment effect. Conclusion : Studies have been conducted on cold hypersensitivity in various fields. But evidence is not enough, so more research will be needed.

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향사이중탕가미방(香砂理中湯加味方)으로 전신냉감과 자한 호전된 여환 1례 (A Case Report of Cold Hypersensitivity and Perspiration Treated with Hyangsayijoongtang-gamibang)

  • 최석영;이미주;김은경;이창훈;이경섭
    • 대한한방체열의학회지
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    • 제9권1호
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    • pp.44-50
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    • 2011
  • Purpose : The purpose of this study is to investigate effect of Hyangsayijoongtang-gamibang on Cold Hypersensitivity and accompanying perspiration. Methods : Hyangsayijoongtang-gamibang was used for a Cold Hypersensitivity patient with accompanying perspiration that was admitted to Kangnam Kyung-Hee Korean Hospital from May 2nd, 2011 to May 14th, 2011. The efficacy of the treatment was evaluated with Digital Infrared Thermal Imaging(DITI). along with objective and subjective observations. Results : After treatments of oriental medicine. the mean body temperature elevated $1.32^{\circ}C$. and the mean temperature difference between different points of the body decreased more than 50%. Subjective observation of Cold Hypersensitivity and accompanying perspiration using Visual Analog Scale(VAS) also showed improvement. Conclusion : Results suggest that Hyangsayijoongtang-gamibang is effective in treating Cold Hypersensitivity patients with accompanying perspiration.

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음한(陰寒)에 대(對)한 문헌적(文獻的) 고찰(考察) (The literature on the genital cold sign(陰寒))

  • 김두희;조충식;김철중
    • 혜화의학회지
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    • 제9권1호
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    • pp.399-407
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    • 2000
  • According to the literature on the genital cold sign, results were as follows. 1. Genital cold sign is that patient feel cold the part outer reproductive system. 2. The primary cause of genital cold sign is the kidney yang vacuity, and the others are the spleen vacuity, fulling down damp-heat, vacuity consumption, frenetic movement of ministerial fire, dedilitation of kidney yin, insecurity of kidney yang, impairment spleen with vacuity consumption, 3. The primary treatment of genital cold sign is warming and recuperating kidney, and the others are enrich yin and norishing blood, supplement the vital energy and enrich blood, clearing away dampness, etc. 4. For the medical prescriptions are used PalMiHyan(八味丸), GeJiGaYongGolMoReoTang(桂枝加龍骨牡蠣湯), GoJinTang(固眞湯), GaGamNaiGoHyan(加減內固丸), SipBoHyan(十補丸), YoSuYuTang(吳茱萸湯), ChungHonTang(淸魂湯), HuiChunSan(回春散), JoYangSan(助陽散), ChungHonTang(淸魂湯), YoncDamSaGanTane(龍膽瀉肝湯), SiHo-SoengSoepTang(柴胡勝濕湯).

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5-HT1A receptors mediate the analgesic effect of rosavin in a mouse model of oxaliplatin-induced peripheral neuropathic pain

  • Li, Daxian;Park, Sangwon;Lee, Kyungjoon;Jang, Dae Sik;Kim, Sun Kwang
    • The Korean Journal of Physiology and Pharmacology
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    • 제25권5호
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    • pp.489-494
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    • 2021
  • Oxaliplatin, a third-generation platinum derivative, is the mainstay of current antineoplastic medications for advanced colorectal cancer therapy. However, peripheral neuropathic complications, especially cold allodynia, undermine the life-prolonging outcome of this anti-cancer agent. Rosavin, a phenylpropanoid derived originally from Rhodiola rosea, exhibits a wide range of therapeutic properties. The present study explored whether and how rosavin alleviates oxaliplatin-induced cold hypersensitivity in mice. In the acetone drop test, cold allodynia behavior was observed from days 3 to 5 after a single injection of oxaliplatin (6 mg/kg, i.p.). Cold allodynia was significantly attenuated following rosavin treatment (10 mg/kg, i.p.). Specific endogenous 5-HT depletion by three consecutive pretreatments with parachlorophenylalanine (150 mg/kg/day, i.p.) abolished the analgesic action of rosavin; this effect was not observed following pretreatment with naloxone (opioid receptor antagonist, 10 mg/kg, i.p.). Furthermore, 5-HT1A receptor antagonist WAY-100635 (0.16 mg/kg, i.p.), but not 5-HT3 receptor antagonist MDL-72222 (1 mg/kg, i.p.), blocked rosavin-induced analgesia. These results suggest that rosavin may provide a novel approach to alleviate oxaliplatin-induced cold allodynia by recruiting the activity of 5-HT1A receptors.

전염성 감염병에 대한 신속변증 시행을 위한 팔강복합증형 표준안 연구 (Studies on the Standard Measure of Compound Patterns of Eight Principles for Rapid Pattern Differentiation against Epidemic Contagious Diseases)

  • 지규용
    • 동의생리병리학회지
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    • 제36권5호
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    • pp.147-154
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    • 2022
  • In order to secure practising rapid pattern(證, zheng) differentiation against acute infectious diseases like corona virus disease-19(COVID-19) showing rapid variation and contagion, a simplified classification of stages centering on the exterior-interior pattern identification with 2 step-subdivision by cold, heat, deficiency, excess pattern and pathogens is proposed. Pattern differentiation by compound patterns of 8 principles is made for the non-severe stage of general cold and the early mild stage of epidemic disease. Compound pattern's names of 8 principles about external infectious diseases are composed of three stages, that is disease site-characters-etiology. Based on early stage symptoms of fever or chilling etc., exterior, interior and half exterior and half interior patterns are determined first, and then cold, heat, deficiency, excess patterns of exterior and interior pattern respectively are determined, and then more concrete differentiation on pathogens of wind, dryness, dampness and dearth of qi, blood, yin, yang accompanied with constitutional and personal illness factors. Summarizing above descriptions, 4 patterns of exterior cold, exterior heat, exterior deficiency, exterior excess and their secondary compound patterns of exterior cold deficiency and exterior cold excess and so on are classified together with treatment method and available decoction for a standard measure of eight principle pattern differentiation.

급만성(急慢性) 혈허(血虛)로 유발된 냉증(冷症) 치험례 (A Case Report of Cold Hypersensitivity Caused by Acute and Chronic Blood Deficiency)

  • 류갑순;이진무;이창훈;조정훈;장준복;이경섭
    • 대한한방부인과학회지
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    • 제22권2호
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    • pp.222-230
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    • 2009
  • Purpose: This study intends to report the effects of Koong Gui Tang on Cold Hypersensitivity caused by acute and chronic Blood Deficiency. Methods: The patients having Cold Hypersensitivity were treated with oriental medicine including herbal medication therapy. Thereafter their health status was analyzed with their own empirical assessments and VAS. Results: After the series of medical treatment, Cold Hypersensitivity caused by acute and chronic Blood Deficiency has shown considerable improvement. Conclusion: This case study shows that Koong Gui Tang therapies are medically effective on Cold Hypersensitivity caused by acute and chronic Blood Deficiency.

Protective effect of platelet-rich plasma against cold ischemia-induced apoptosis of canine adipose-derived mesenchymal stem cells

  • Suji Shin;Sung-Eon Kim;Seong-Won An;Seong-Mok Jeong;Young-Sam Kwon
    • 대한수의학회지
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    • 제64권1호
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    • pp.2.1-2.8
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    • 2024
  • This study was performed to assess the antiapoptotic effect of canine platelet-rich plasma (PRP) treated on the canine adipose-derived mesenchymal stem cells (cMSCs) under cold ischemic conditions. The effect of preventing apoptosis of cMSCs was evaluated in the apoptotic condition induced by cold ischemic injury in vitro. To determine the progression of apoptosis, the changes in cell nucleus were observed using 4',6-diamidino-2-phenylindole (DAPI) fluorescence staining. In addition, we examined the mitochondrial membrane potential (MMP) and caspase-3 activity. When the cold hypoxic injury was applied to cMSCs, the apoptotic change was observed by DAPI staining, mitochondrial staining for MMP, and caspase-3 assay. PRP significantly decreased the number of apoptotic cells. Nuclear shrinkage and fragmentation of apoptotic cells in control groups were observed by DAPI staining. The MMP was recovered by the treatment of PRP. In addition, when the luminescence intensity was measured for caspase-3 activity, the value was significantly higher in the PRP treated groups than the control groups. The results of this study showed that the PRP may have a beneficial effect on apoptosis induced by cold ischemic injury.

304 스테인리스 강의 가공유기 마르텐사이트와 기계적 거동에 미치는 온도의 영향 (Effects of annealing temperature on strain-induced martensite and mechanical properties of 304 stainless steel)

  • 이상훈;최점용;남원종
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2008년도 추계학술대회 논문집
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    • pp.203-206
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    • 2008
  • Transformation of austenite to martensite during cold rolling has been widely used to strengthen metastable austenitic stainless steel grades. Aging treatment of cold worked metastable austenitic stainless steels, including ${\alpha}'$-martensite phase, results in the further increase of strength, when aging is performed in $200^{\circ}C$ to $450^{\circ}C$ temperature range. The purpose of the present study was to evaluate the effect of time and temperature on the stress-strain behavior of cold worked austenitic stainless steels. The amount of ${\alpha}'$-martensite during cold working and aging was examined by ferrite scope and X-ray diffraction (XRD). During aging at $450^{\circ}C$ for 1hr, tensile strength dramatically increased by 150MPa. Deformed metastable austenitic steels containing the "body-centered" ${\alpha}'$-martensite are strengthened by the diffusion of interstitial solute atoms during aging at low temperature.

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