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Fatigue of 0.55C-1.72Si Steel with Tempered Martensitic and Carbide-Free Bainitic Microstructures

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Acta Metallurgica Sinica(English Letters) 2014年第1期27卷 55-62页

作者： Alejandro Leiro Arash Roshan Karl-Gustaf Sundin esa vuorinen Braham Prakash Department of Engineering Sciences and Mathematics Lule University of Technology

High-Si spring steel was heat treated in three different ways： Quenching and tempering at 460 ℃ to obtain a tempered martensite microstructure, and austempering at 300 and 350 ℃, respectively, to obtain two different carbide-free bainitic microstructures. In the steel austempered at 350 ℃, both the bainite lath thickness and retained austenite content were higher than those of the steel austempered at 300 ℃. Rotating-bending fatigue tests were done in order to evaluate the effect of each heat treatment on the high-cycle fatigue behavior of the steel. When the austempering temperature was 300 ℃, the endurance limit was increased by 25% despite a 5% reduction in tensile strength when compared with that of the quenched and tempered steel. The relationship between endurance limit [Rfat （50~）] and ultimate tensile strength （Rm） was higher for the austempered samples in comparison with that of the quenched and tempered material. Therefore, it is believed that the presence of retained austenite affects the relationship between endurance limit and tensile strength.

关键词： Steels Fatigue Carbide-free bainite TRIP effect

Wafer-level SLID bonding for MEMS encapsulation

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Advances in Manufacturing 2013年第3期1卷 226-235页

作者： H.Xu T.Suni V.vuorinen J.Li H.Heikkinen P.Monnoyer M.Paulasto-Krckel Department of Electronics School of Electrical EngineeringAalto University VTT Technical Research Centre of Finland

Hermetic packaging is often an essential requirement to enable proper functionality throughout the device＇s lifetime and ensure the optimal performance of a micro electronic mechanical system （MEMS） device. Solid-liquid interdiffusion （SLID） bonding is a novel and attractive way to encapsulate MEMS devices at a wafer level. SLID bonding utilizes a low-melting-point metal to reduce the bonding process temperature; and metallic seal rings take out less of the valuable surface area and have a lower gas permeability compared to polymer or glass- based sealing materials. In addition, ductile metals can adopt mechanical and thermo-mechanical stresses during their service lifetime, which improves their reliability. In this study, the principles of Au-Sn and Cu-Sn SLID bonding are presented, which are meant to be used for wafer-level hermetic sealing of MEMS resonators. Seal rings in 15.24 cm silicon wafers were bonded at a width of 60 gin, electroplated, and used with Au-Sn and Cu-Sn layer structures. The wafer bonding temperature varied between 300 ℃ and 350 ℃, and the bonding force was 3.5 kN under the ambient pressure, that is, it was less than 0.1 Pa. A shear test was used to compare the mechanical properties of the interconnections between both material systems, in addition, important factors pertaining to bond ring design are discussed according to their effects on the failure mechanisms. The results show that the design ofmetal structures can significantly affect the reliability of bond rings.

关键词： (MEMS)bondingDefects Micro electronic mechanical systemSolid-liquid interdiffusion (SLID)Transient liquid-phase (TLP) bondingShear test Reliability

Human dental pulp stem cells differentiate into neural precursors but not into mature functional neurons

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Stem Cell Discovery 2012年第3期2卷 85-91页

作者： Riikka Aanismaa Jenna Hautala Annukka vuorinen Susanna Miettinen Susanna Narkilahti Adult Stem Cell Group Institute of Biomedical Technology University of Tampere Tampere Finland Neuro Group Institute of Biomedical Technology University of Tampere Tampere Finland

Large numbers of neuronal cells are needed for regenerative medicine to treat patients suffering from central nervous system diseases and deficits such as Parkinson’s disease and spinal cord injury. One suggestion has been the utilization of human dental pulp stem cells (hDPSCs) for production of neuronal cells which would offer a patient-specific cell source for these treatments. Neuronal differentiation of hDPSCs has been described previously. Here, we tested the differentiation of DPSCs into neuronal cells with previously reported protocol and characterized the cells according to their morphology, gene and protein expressions and most importantly according to their spontaneous electrical functionality with microelectrode array platform (MEA). Our results showed that even though hDPSC-derived neural progenitor stage cells could be produced, these cells did not mature further into functional neuronal cells. Thus, utilization of DPSCs as a cell source for producing grafts to treat neurological deficits requires more efforts before being optimal.

关键词： Dental Pulp Stem Cell Neural Differentiation Neural Networks

Unified description of deconfined QCD equation of state

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Unified description of deconfined QCD equation of state

The 19th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions

作者： A. Ipp K. Kajantie A. Rebhan A. vuorinen ECT* Villa TambosiStrada delle Tabarelle 286I-38050 Villazzano TrentoItaly Department of Physics P.O. Box 64FI-00014 University of HelsinkiFinland Institut fu¨r Theoretische Physik Technische Universit¨at WienWiedner Hauptstr. 8-10A-1040 ViennaAustria Department of Physics University of WashingtonSeattleWA 98195U.S.A.

＜正＞We present a new method for the evaluation of the perturbative expansion of the QCD pressure which is valid at all values of the temperature and quark chemical potentials in the deconfined phase and which we work out up to and including order g4 accuracy. In various limits, we recover the known results of dimensional reduction and the HDL and HTL resummation schemes, as well as

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从矿石中溶出铁和铀的氧化还原和沉淀反应

湿法冶金 1986年第4期 55-57页

作者： A.vuorinen 胡长柏

用酸性硫酸铁溶液浸出铀矿样25小时的结果表明,浸出液中FeOH2+与Fe2+浓度的变化是相反的,二者均反映了矿石物料还原三价铁的情况。起初,可溶性总铁浓度因铁的硫化物溶解而增高,然后又随Fe（Ⅲ）的沉淀而降低。在浸出时间临近终点时,出... 详细信息

用酸性硫酸铁溶液浸出铀矿样25小时的结果表明,浸出液中FeOH2+与Fe2+浓度的变化是相反的,二者均反映了矿石物料还原三价铁的情况。起初,可溶性总铁浓度因铁的硫化物溶解而增高,然后又随Fe（Ⅲ）的沉淀而降低。在浸出时间临近终点时,出现了可溶性铀的损失,这表明在细菌作用下所产生的硫酸铁溶液中铀与Fe（Ⅲ）是共沉淀的。

关键词：亚铁离子 Fe 共沉淀二价铁离子硫化矿物硫化物矿物硫酸铁三价铁离子沉淀物氧化还原溶出

漂流海藻垫威胁着芬兰西南部群岛海的海底吗?

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AMBIO－人类环境杂志 2000年第6期29卷 338-343页

作者： Petri Vahteri Anita Mkinen Sonja Salovius Ilppo vuorinen 周立志图尔库大学 bo

借助水底摄像系统和潜水呼吸器,获得1996～1997年夏季漂流海藻群在波罗的海北部的群岛海(Archipelago Sea)发生情况图。研究范围包括从诲滨到海洋50m的深度范围。按藻群的厚度和是否发生缺氧现象(硫化氢气味,黑色沉淀物),亦即藻群潜在... 详细信息

借助水底摄像系统和潜水呼吸器,获得1996～1997年夏季漂流海藻群在波罗的海北部的群岛海(Archipelago Sea)发生情况图。研究范围包括从诲滨到海洋50m的深度范围。按藻群的厚度和是否发生缺氧现象(硫化氢气味,黑色沉淀物),亦即藻群潜在的各种生态学影响,对藻群进行了描述和分类。可以区分出三种不同类型的漂流海藻群:藻盖、藻垫和藻床。对藻群在一个生长季节的演替情况进行了研究。开始,藻类在海底聚集成一薄层;之后,这些薄层海藻开始沿海底坡面向下沉,发展为在一定程度上厌氧的藻垫;最后成为完全厌氧的藻床。在研究区东南角的外群岛海,这种现象把为明显。有利于生活史较短的藻类生长、导致漂流藻垫形成的众多因子包括海水中高营养含量、较好的透明度和适易的基质。研究期间,我们深感水下摄像系统是用来研究水下松散藻群的理想工具:

关键词：漂流海藻群群岛海海底藻垫生态监测海洋生态

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淋巴细胞性脑膜炎复发与疱疹病毒感染

世界核心医学期刊文摘（神经病学分册） 2005年第3期1卷 13-14页

作者： Kupila L. Vainionp R. vuorinen T. 黄卫东 Department of Neurology Turku University Central Hospital Kii namyllynkatu 4-8 20520 Turku Finland Dr.

Background: Herpes simplex virus 2 (HSV 2) and HSV 1 have been recognized as causes of recurrent aseptic lymphocytic meningitis (RALM). However, the role of other herpesviruses has not been systematically assessed. Objectives: To evalua te the cause of RALM by using polymerase chain reaction (PCR) tests detecting v aricellazoster virus (VZV), cytomegalovirus (CMV), or human herpesvirus 6 (HHV 6), in addition to HSV, on cerebrospinal fluid (CSF) samples; and to assess the utility of PCR and antibody analyses in consecutive episodes of RALM. Designs: T he PCR and antibody results for herpesviruses were analyzed from 14 patients hav ing 48 episodes of RALM. Results: The CSF PCR results for VZV, CMV, and HHV 6 w ere negative in 12, 10, and 11 patients investigated, respectively, and antibodi es against VZV, CMV, and HHV 6 showed only old immunity. Herpes simplex virus 2 was detected from the CSF in 10 patients, and HSV 1 in 1 patient. In 6 of thes e 11 patients, the HSV PCR result was positive in more than one disease episode. A significant increase of serum antibodies for HSV was seen in only 1 of 15 epi sodes examined. An intrathecal antibody response to HSV was not recognized in 9 episodes investigated in these 11 patients. Conclusions: We could not find evide nce of VZV, CMV, or HHV 6 in the pathogenesis of RALM, although most patients w ere previously infected by those viruses. Herpes simplex virus 2 was detected fr om the CSF in most patients, and often repeatedly, which further confirms the ro le of this virus in RALM. The causative diagnosis was obtained only by PCR, wher eas antibody analysis was not clinically useful.

关键词：疱疹病毒感染带状疱疹病毒患者脑脊液抗体检测结果人类疱疹病毒巨细胞病毒抗体反应病因诊断系统性研究

Evaluation of brain tumor metabolism with [^(11)C] choline PET and ~1H-MRS.

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中国神经肿瘤杂志 2003年第2期1卷 77-77页

作者： Utriainen M Komu M vuorinen V Lehikoinen P Sonninen P Kurki T Utriainen T Roivainen A Kalimo H Minn H Turku PET Centre Department of PediatricsUniversity of TurkuTurkuFinland.

BACKGROUND:The signal of choline containing compounds（Cho）in proton magnetic resonance spectroscopy（1H-MRS）is elevated in brain tumors.[11C]choline uptake as assessed using positron emission tomography（PET）has also been suggested to be higher in brain tumors than in the normal *** examined whetherquantitative analysis of choline accumulation and content using these 1wo novel techniques would be helpful innon-invasive,preoperative evaluation of suspected brain tumors and tumor malignancy ***:12patients with suspected brain tumor were studied using[11C]choline PET,gadolinium enhanced 3-D magneticresonance imaging and1H-MRS prior to diagnostic biopsy or *** normal subjects served as

关键词： MRS Evaluation of brain tumor metabolism with PET choline PET and of

人通过膳食对波罗的海鲱鱼有机氯的摄入:个体鱼类差别和渔业管理所引起的后果

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AMBIO－人类环境杂志 2007年第2期36卷 244-251页

作者： Mikko Kiljunen Mari Vanhatalo Samu Mntyniemi Heikki Peltonen Sakari Kuikka Hannu Kiviranta Raimo Parmanne Jouni T.Tuomisto Pekka J.vuorinen Anja Hallikainen Matti Verta Jukka Pnni Roger I.Jones Juha Karjalainen 赵绪才芬兰于韦斯屈莱大学芬兰赫尔辛基大学国家公共卫生研究所芬兰游钓和渔业研究所芬兰食品安全局芬兰环境研究所(SYKE) 于韦斯屈莱大学

该研究探讨了芬兰人通过膳食摄入的源于波罗的海北部鲱鱼的有机氯(PCDD/F和PCB)可以受渔业管理影响的程度。这项研究是通过利用通用的模型工具(例如鲱鱼的种群模型和生物能量学模型等)对人的摄入量进行估计来开展的。我们利用概率方法... 详细信息

该研究探讨了芬兰人通过膳食摄入的源于波罗的海北部鲱鱼的有机氯(PCDD/F和PCB)可以受渔业管理影响的程度。这项研究是通过利用通用的模型工具(例如鲱鱼的种群模型和生物能量学模型等)对人的摄入量进行估计来开展的。我们利用概率方法来说明由于鲱鱼个体的变化而导致的人体摄入有机氯的变化。我们的估计与目前的预防限量和使用建议进行了比较。结果表明现在鲱鱼的消费水平和频率很有可能超过了所建议的PCDD/F PCB的摄入限量。此外,我们的研究结果清楚地表明在对类二恶英有机氯的风险管理中,对捕鱼的调节(在这种情况下增加捕鱼压力)远不及调节对鲱鱼的消费更能减少风险。增加捕鱼仅仅稍微的减少芬兰鱼货市场上的鲱鱼的有机氯浓度。

关键词：波罗的海渔业管理摄入量有机氯鲱鱼鱼类个体膳食