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中国冶金 2016年第1期26卷 23-30页

作者：昝娜丁桦骆小鹏唐正友 bleck wolfgang 东北大学材料与冶金学院辽宁沈阳110819 亚琛工业大学钢铁研究所亚琛52072 中国核工业第五建设有限公司福清核电总包部上海201512

主要研究了晶粒尺寸对Fe-17Mn-1Al-0.6CTWIP钢的氢脆行为的影响。原始材料经过不同的热处理制度,得到晶粒尺寸为17和45μm的材料。通过慢拉伸试验研究氢质量分数在0~0.001%材料的氢脆敏感性。试验结果表明,充氢后的试验材料比未充氢试... 详细信息

主要研究了晶粒尺寸对Fe-17Mn-1Al-0.6CTWIP钢的氢脆行为的影响。原始材料经过不同的热处理制度,得到晶粒尺寸为17和45μm的材料。通过慢拉伸试验研究氢质量分数在0~0.001%材料的氢脆敏感性。试验结果表明,充氢后的试验材料比未充氢试验材料易发生氢脆,充氢后的试验材料断裂强度和断裂应变均降低。随着晶粒尺寸的增大,试验材料的氢脆敏感性增强。在氢质量分数为0.001%,晶粒尺寸增加到45μm时,应变损失率为17%,随着晶粒尺寸的增大,氢脆敏感性增加的原因是晶粒尺寸较大的材料孪晶较早出现,孪晶密度较大,同时单位晶界氢质量分数增加。

关键词： TWIP钢氢脆晶粒尺寸孪晶

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汽车钢板断裂行为的多尺度研究

汽车钢板断裂行为的多尺度研究

Correlates of long-term physical activity adherence in women

第十三届中国钢铁年会

作者：郭晓菲张梅赵洪山 bleck wolfgang 董瀚上海大学材料科学与工程学院亚琛工业大学钢铁研究所

汽车用钢的研发沿着高强韧轻量化路径不断前进,在近二十年的历程中,第二、三代高强汽车钢板在生产工艺及力学性能的优化方面日趋成熟。新一代高强汽车板的组织结构多通过细晶化,多相化设计提高强度,并通过引入不稳态奥氏体结构的TRIP效... 详细信息

汽车用钢的研发沿着高强韧轻量化路径不断前进,在近二十年的历程中,第二、三代高强汽车钢板在生产工艺及力学性能的优化方面日趋成熟。新一代高强汽车板的组织结构多通过细晶化,多相化设计提高强度,并通过引入不稳态奥氏体结构的TRIP效应,以及孪晶硬化的TWIP效应改进材料塑性。但多相及TRIP/TWIP效应的引入也带来一系列服役方面的问题,材料的服役性能,如滞后断裂,疲劳,远低于材料表观力学性能,影响产品的使用安全。因而,通过多尺度表征与测试解析新材料断裂机制与断裂行为,从而进一步改进材料组织结构设计,并设定材料安全应用边界,对高强韧新型汽车钢的推广有重要的指导意义。本研究以高锰奥氏体钢、中锰钢为例,通过对材料断裂行为从微观,介观到宏观的多尺度表征,揭示材料在不同尺度的断裂行为。在微观表征上采用扫描隧道显微(ECCI)和电子背散射衍射(EBSD)相结合的方式,表征高锰奥氏体钢中位错和孪晶行为对裂纹萌生的影响。在介观到宏观尺度表征上,采用结合GOM数字图像关联技术(DIC)及断口区域的电子背散射衍射组织分析,探讨局部形变对组织结构及裂纹萌生的影响。进而探索建立材料组织结构与材料断裂和服役安全性能的联系,为现行高强汽车钢板的应用及服役性能评价提供参考。

关键词：高强汽车钢微观组织断裂行为

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Journal of Sport and Health Science 2017年第4期6卷 434-442页

作者： Haichun Sun Cheryl A. Vamos Sara S.B. Flory Rita DeBate Erika L. Thompson Jennifer bleck Department of Teaching and Learning College of Education University of South Florida Tampa FL 33620 USA Department of Community and Family Health College of Public Health University of South Florida Tampa FL 33612 USA

Background: Little is known about the factors that may influence women's adherence to moderate-to-vigorous physical activity(MVPA) using longitudinal data. The purpose of this study was to examine the correlates of long-term physical activity(PA) participation among ***: Female data from Waves I, III, and IV(n = 5381) of the National Longitudinal Study of Adolescent to Adult Health(Add Health) were used for the analysis. The outcome of PA adherence was operationalized as(1) consistently physically active(at least 5 instances during the week)in both Waves III and IV(during adulthood), and(2) consistently not physically active or only physically active in either Wave III or IV. Predictor variables from Wave I(during adolescence) included race/ethnicity, PA level, self-perception of being physically fit, general health status, attempt to change weight, parents' income level, parents' education, well-being, depression, access to PA resources, days of physical education(PE), and grade level. Crude and adjusted logistic regression models were utilized to estimate the adjusted odds ratio(a OR) and 95% confidence interval(95%CI) for the outcome ***: PA levels during adolescence significantly predicted PA adherence(a OR = 1.67, 95%CI: 1.35–2.05). Additionally, wanting to lose weight(a OR = 1.49, 95%CI: 1.20–1.85), using fitness center in the neighborhood(a OR = 1.29, 95%CI: 1.05–1.58), and having 5 days of PE a week(a OR = 1.48, 95%CI: 1.09–2.02) were significant predictors. Women who did not perceive being physically fit(a OR = 0.65, 95%CI: 0.44–0.95)and Black, non-Hispanics(a OR = 0.60, 95%CI: 0.44–0.82) were less likely to adhere to ***: The findings suggested that physically active adolescents were more likely to become active adults. Future research should address interventions(e.g., PE program, community resources) that may promote lifetime PA in women, with the goal of decreasing morbidity and mortality.

关键词： Females Longitudinal Moderate-to-vigorous physical activity Social ecological frameworks

Changes of duplex parameters and splenic size in liver transplant recipients during a long period of observation

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World Journal of Gastroenterology 2005年第43期11卷 6787-6791页

作者： Bita Boozari Michael Gebel Mathias J Bahr Michael P Manns Christian P Strassburg Joerg S bleck J Klempnauer Bjoern Nashan Department of Gastroenterology Department of Visceral and Transplant Surgery Department of Transplant Surgery

AIM: To assess the changes of portal and arterial velocities, resistance index, spleen and liver size during a long observation period (13.7 years) after orthotopic liver transplantation (OLT).METHODS: Two hundred and sixty patients were recruited retrospectively for this study and divided into groups with defined time intervals after OLT. The cross-sectional changes of portal and arterial velocities,resistance index, spleen and liver size between the defined time intervals were studied. The complications detected by ultrasound were compared to gold standard ***: The mean values for liver size were all within the normal range. The splenic size decreased between the time intervals 100 and 1 000 d after OLT (t;P＜0.01).While portal and arterial flow velocities decreased up to 5.5 years (t; portal velocity P＜0.01, maximal systolic velocity P=0.05, maximal end diastolic velocity P＜0.01),RI increased during this interval (t:P＜0.01). Higher RIvalues were found in older patients (r = 0.24, P＜0.001).CONCLUSION: The arterial and portal velocities show adaptation processes continuing over the course of many years after OLT and are reported for the first time. The vascular complications detected by ultrasound occur mostly up to 100 d after OLT.

关键词： Ultrasound Color Doppler Liver transplantation Monitoring

Static Softening Behaviour of Hot-worked Austenite in Microalloyed Structural Steel StE460

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International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 35-43页

作者： Fuming Wang Li Tang J -J. Esser W bleck (Applied Science School, University of Science and Technology Beliing, Beliing 100083, China)(Paashihua Steelworks, Sichuan 617000, China)(Aachen University of Technology, Germany Applied Science School University of Science and Technology Beijing Beijing 100083 China Panzhihua Steelworks Sichuan 617000 China Aachen University of Technology Germany

Double-hit compression tests were performed on StE460 steel containing microalloying elements niobium and vanadium over a range of temperatures and strain rates penment to hot rolling. The fractional softening was evaluated by use of the offset method, which was confirmed to be a very reasonable method. Appropriate expressions are given for the static recrystallization kinetics as a function of temperature and strain rate. Particular attention is paid to the effect of strain rate on static recrystallization. It can be shown that the static softening is apparently accelerated by strain rate. Recrystallization in low temperature austenitic region is stopped due to precipitation of carbonitrides of microalloying elements, which is reflected in the form of a plateau in the curves of static softening.

关键词： microalloying elements precipitation of carbonitrides static softening

Initial experience from a combination of systemic and regional chemotherapy in the treatment of patients with nonresectable cholangiocellular carcinoma in the liver

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World Journal of Gastroenterology 2005年第8期11卷 1091-1095页

作者： Timm Kirchhoff Lars Zender Sonja Merkesdal Bernd Frericks Nisar Malek Joerg bleck Stefan Kubicka Stefan Baus Ajay Chavan Michael P.Manns Michael Galanski Department of Diagnostic Radiology Department of Gastroenterology Division of Rheumatology Department of Radiology and Nuclear Medicine

AIM: In nonresectable cholangiocellular carcinoma (CCC)therapeutic options are limited. Recently, systemic chemotherapy has shown response rates of up to 30%.Additional regional therapy of the arterially hyper vascularized hepatic tumors might represent a rational approach in an attempt to further improve response and palliation. Hence, a protocol combining transarterial chemoembolization and systemic chemotherapy was applied in patients with CCC limited to the ***: Eight patients (6 women, 2 men, mean age 62 years) with nonresectable CCC received systemic chemotherapy (gemcitabine 1 000 mg/m2) and additional transarterial chemoembolization procedures (50 mg/m2cisplatin, 50 mg/m2 doxorubicin, up to 600 mg degradable starch microspheres). Clinical follow-up of patients, tumor markers, CT and ultrasound were performed to evaluate maximum response and ***: Both systemic and regional therapies were tolerated well; no severe toxicity (WHO Ⅲ/Ⅳ) was encountered. Nausea and fever were the most commonly observed side effects. A progressive rarefication of the intrahepatic arteries limited the maximum number of chemoembolization procedures in 4 patients. A median of 2 chemoembolization cycles (range, 1-3) and a median of 6.5 gemcitabine cycles (range, 4-11) were *** responses were not achieved. As maximum response, partial responses were achieved in 3 cases,stable diseases in 5 cases. Two patients died from progressive disease after 9 and 10 mo. Six patients are still alive. The current median survival is 12 mo (range, 9-18); the median time to tumor progression is 7 mo (range, 3-18). Seven patients suffered from tumor-related symptoms prior to therapy, 3 of these experienced a treatment-related clinical relief. In one patient the tumor became resectable under therapy and was successfully removed after 10 ***: The present results indicate that a combination of systemic gemcitabine therapy and repeated regional chemoembolizati

关键词： Cholangiocellular carcinoma Gemcitabine Intraarterial chemoembolization

Transcutaneous perianal sonography:A sensitive method for the detection of perianal inflammatory lesions in Crohn's disease

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World Journal of Gastroenterology 2004年第19期10卷 2859-2863页

作者： Jochen Wedemeyer Timm Kirchhoff Gernot Sellge Oliver Bachmann Joachim Lotz Michael Galanski Michael P.Manns Michael J.Gebel Jrg S.bleck Department of Gastroenterology Hepatology and EndocrinologyMedical School of HannoverCarl Neuberg Str.130623 HannoverGermany M.D. Department of Diagnostic Radiology Medical School of HannoverCarl Neuberg Str.130623 HannoverGermany Department of Gastroenterology Hepatology and EndocrinologyMedical School of HannoverCarl Neuberg Str.130623 HannoverGermany

AIM:Pelvic magnetic resonance imaging(MRI)and endoanal ultrasound which are established imaging methods for perianal inflammatory lesions in patients with Crohn's disease require expensive specialized equipments and *** investigated the feasibility and sensitivity of transcutaneous perianal ultrasound(PAUS)using regular ultrasound probes in the imaging of perianal inflammatory *** sonographic findings were correlated to pelvic MR]-scans. METHODS:We performed PAUS in 25 patients with Crohn's disease and clinical signs of perianal inflammatory disease. Wibhin a median of 10 d(range 0-75)these patients underwent MRI of the *** convex and linear high resolution probes were used for *** sonographic findings were correlated to the MRI findings by blinded investigators. RESULTS:The sonographic investigations were well tolerated by all *** typically presented as hypoechoic ***-nine fistulae were detected in 22 *** were detected in 7 patients and presented as hypo-or anechoic ***-six of 29 fistulae and 6 of 7 abscesses could be confirmed by *** statistics showed an excellent agreement (kappa>0.83)between the two imaging methods. CONCLUSION:PAUS is a simple,painless,feasible,real- time method that can be performed without specific patient preparation which is comparable in its sensitivity to pelvic MRI in the detection of perianal fistulae and/or abscesses. PAUS can especially be recommended as a screening tool in acute perianal disorders such as perianal abscess and for follow-up studies of perianal inflammatory disease.

关键词： Anal Canal histology Anus Diseases Crohn Disease Humans Inflammation Ultrasonography, Doppler, Color

Combination of repeated single-session percutaneous ethanol injection and transarterial chemoembolisation compared to repeated single-session percutaneous ethanol injection in patients with non-resectable hepatocellular carcinoma

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World Journal of Gastroenterology 2006年第23期12卷 3707-3715页

作者： Arne Dettmer Timm D Kirchhoff Michael Gebel Lars Zender Nisar P Malek Bernhard Panning Ajay Chavan Herbert Rosenthal Stefan Kubicka Susanne Krusche Sonja Merkesdal Michael Galanski Michael P Manns Joerg S bleck Department of Gastroenterology Hepatology and EndocrinologyHannover Medical SchoolGermany Department of Diagnostic Radiology Hannover Medical SchoolGermany Department of Anaesthesiology Hannover Medical SchoolGermany Department of Diagnostic and Interventional Radiology Klinikum OldenburgGermany S bleck Department of GastroenterologyHepatology and EndocrinologyHannover Medical SchoolGermany Division of Rheumatology Hannover Medical SchoolGermany

AIM： To evaluate the treatment effect of percutaneous ethanol injection （PEI） for patients with advanced, non-resectable HCC compared with combination of transarterial chemoembolisation （TACE） and repeated single-session PEI, repeated single-session PEI alone, repeated TACE alone, or best supportive care. METHODS： All patients who received PEI treatment during the study period were included and stratified to one of the following treatment modalities according to physical status and tumor extent： combination of TACE and repeated single-session PEI, repeated single-session PEI alone, repeated TACE alone, or best supportive care. Prognostic value of clinical parameters including Okuda-classification, presence of portal vein thrombosis, presence of ascites, number of tumors, maximum tumor diameter, and serum cholinesterase （CHE）, as well as Child-Pugh stage, α-fetoprotein （AFP）, fever, incidence of complications were assessed and compared between the groups. Survival was determined using Kaplan-Meier and multivariate regression analyses.

关键词： HCC Single-session PEI TACE Survival Prediction