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Effect of quenching rate on microstructure and mechanical properties of commercial AA7108 aluminium alloy

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Transactions of Nonferrous Metals Society of China 2012年第8期22卷 1872-1877页

作者： Ida WESTERMANN Ann Leni HAUGSTAD yngve LANGSRUD Knut MARTHINSEN SINTEF Materials and Chemistry NO-7465TrondheimNorway Department of Materials Science and Engineering Norwegian University of Science and TechnologyNO-7491TrondheimNorway Benteler Aluminium Systems Norway AS NO-2830RaufossNorway

A commercial AA7108 aluminium alloy subjected to different quenching procedures from the solid solution temperature of 480 ℃ was considered. Both continuously cooling and quenching to intermediate temperatures （400, 300 and 200 ℃） followed by different holding times were applied. All the materials were subsequently subjected to the same industrial two-step artificial ageing procedure to obtain a maximum strength （T6）. Tensile testing of the different quenched materials in the T6 temper reveals a large deviation in strength dependent on the cooling/holding time, compared with the reference sample. A collection of the different quenched materials was chosen for further investigation of the precipitate structure by transmission electron microscopy （TEM） to explain the differences in mechanical properties.

关键词： aluminium microstructure precipitate free zone mechanical properties

应变率效应对无铅焊锡接点跌落冲击力学行为的影响

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北京工业大学学报 2010年第8期36卷 1015-1019页

作者：秦飞李建刚安彤刘亚男 WANG yngve 北京工业大学机械工程与应用电子技术学院北京100124 Intel(中国)有限公司上海200000

采用应变率相关的Johnson-Cook材料模型和率无关的弹塑性模型分别计算了跌落/冲击载荷下焊锡接点的应力及应变,研究应变率对焊锡接点力学行为的影响,预测了焊锡接点的破坏情况,并与动态4点弯曲实验结果进行了比较.结果表明:焊锡材料的... 详细信息

采用应变率相关的Johnson-Cook材料模型和率无关的弹塑性模型分别计算了跌落/冲击载荷下焊锡接点的应力及应变,研究应变率对焊锡接点力学行为的影响,预测了焊锡接点的破坏情况,并与动态4点弯曲实验结果进行了比较.结果表明:焊锡材料的应变率效应对电路板的挠度几乎没有影响,但对焊锡接点的应力及应变有较大影响;不考虑应变率效应的弹塑性模型低估焊锡接点的应力值而高估等效塑性应变值;采用率相关的Johnson-Cook模型能更好地预测焊锡接点的力学行为,能较真实地预测焊锡接点的破坏情况.

关键词：应变率效应焊锡接点跌落冲击电子封装

Metso化学制浆新技术——非木材制浆方法

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中华纸业 2003年第3期24卷 22-24页

作者： yngve Lundahl

非本材制浆方法本刊今年前两期介绍了Metso公司开发的先进的木材制浆技术,Metso在非木材制浆工艺与设备方面亦有独到之处……

关键词：造纸 Metso公司化学制浆新技术非木材制浆

Improved Quality of Concrete Surfaces by a Vertical Compaction

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Improved Quality of Concrete Surfaces by a Vertical Compacti...

Purpose in life among very old men

国际桥梁2004年大会

作者： yngve ALVARSSON www.formconsult.se Formconsult AB Huddinge Stockholm SWEDEN

Most equipment used today to screed and compacting concrete are not specially designed to give a dense and well compacted concrete cover. It has until now been a lack of suitable equipment to complete a re-vibration of fresh concrete placed in-situ in horizontal surfaces. Other production problems with conventional equipment’s include how to better consolidate thin toppings or overlays of concrete. In order to improve the adhesive of the mortar to the adjacent reinforcing bars and reduce voids under the bars caused by settlement in the concrete mass are other causes why a new compaction technique needed to be developed. Both re-vibration and additional consolidation of the upper part of a horizontal surface can now be done. Structures obtain a more durable surface if treated according to this method.

关键词： Bandmaskinen RolliT Motorslodan compaction re-vibration slabs bridges repair voids overlays,

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Advances in Aging Research 2013年第3期2卷 100-105页

作者： Pia Hedberg yngve Gustafson Christine Brulin Lena Alex Department of Nursing Umea UniversityUmeaSweden Department of Community Medicine and Rehabilitation Geriatric MedicineUmea UniversityUmeaSweden

This paper provides very old men’s experiences of and reflections on purpose in life. The answers from an interview question about purpose in life from 23 men were analyzed by using qualitative content analysis. The results revealed three content areas: talking of purpose of life in general, talking of own purpose in life and reflections on purpose in life. Our findings showed that very old men experienced purpose in life most strongly when remembering the past and describing their earlier work. The old men reflected on purpose in life not just from their own individual perspectives, but also from a more reflective and analytic perspective.

关键词： Aging Men Narrative Analysis Qualitative Content Analysis Purpose in Life

High Winds at Nyg?rdsfjell

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High Winds at Nyg?rdsfjell

Steroids reduce local inflammatory mediator secretion and mucosal permeability in collagenous colitis patients

作者： Muhammad Bilal yngve Birkelund Matthew Homola Department of Physics and Technology at the Arctic University of Norway (Uit) Department of Engineering and Safety at the Arctic University of Norway (Uit) Nordkraft Vind

Wind energy in cold climate offers challenges that include among others, the icing on the turbine blades that affects the power output of the turbines. We investigate the presence of high winds at the Nyg?rdsfjell wind farm that is situated in north of the Arctic Circle in Norway. The data is taken from three 2.3 MW Siemens wind turbines(SWT-2.3-93) that were installed at Nyg?rdsfjell during the fall of 2005. There are total of 185 high winds events detected consisting of 1737 hours during the observation period May 2008 until April 2009. Out of these 1737 hours of high winds, 269 hours occurred during May2008 until October 2008 and 1468 hours occurred during November 2008 until April 2009 that is 84.5% of total high winds hours. That shows the majority of high winds events occurring during the colder periods. The ten leading high winds events showed the presence of wind speeds ranging from 16 m/s to 19 m/s with maximum up to 24 m/s. The analysis established the existence of high winds at Nyg?rdsfjell during colder times.

关键词： High winds Nyg?rdsfjell wind energy in cold climate

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World Journal of Gastroenterology 2006年第43期12卷 7012-7018页

作者： Yesuf Taha yngve Raab Marie Carlson Anders Larsson Mikael Lrdal Lars Lf Magnus Thrn Departments of Medical Sciences University Hospital Uppsala Sweden Department of Medicine KarolinskaInstitutet Karolinska University Hospital Huddinge Sweden Departments of Medical Sciences University Hospital Uppsala Sweden Departments of Clinical Chemistry University Hospital Uppsala Sweden Department of Medicine KarolinskaInstitutet Karolinska University Hospital Huddinge Sweden Center for Clinical Research Central Hospital Vsters Sweden Department of Surgery Karolinska Institutet South Stockholm General Hospital Stockholm Sweden

AIM：. To study the effect of oral steroids upon clinical response and rectal mucosa secretion of eosinophil cationic protein （ECP）, myeloperoxidase （NPO）, basic fibroblast growth factor （bFGF）, vascular endothelial growth factor （VEGF） and albumin in patients with collagenous colitis （CC）. METHODS： A segmental perfusion technique was used to collect perfusates from rectum of CC patients once before and twice （one and four weeks） after the start of steroid treatment. Clinical data was monitored and ECP, MPO, bFGF, VEGF and albumin concentrations were analyzed by immunochemical methods in perfusates and in serum. RESULTS： Steroids reduced the number of bowel movements by more than five times within one week and all patients reported improved subjective wellbeing at wk 1 and 4. At the same time, the median concentrations of ECP, bFGF, VEGF and albumin in rectal perfusates decreased significantly. MPO values were above the detection limit in only 3 patients before treatment and in none during treatment. VEGF, bFGF, ECP and albumin concentrations correlated with each other with the exception of ECP and albumin. A decrease of serum ECP and VEGF concentrations was also seen even if the overtime reduction was not significant.CONCLUSION： Oral steroid treatment in CC patients induced a simultaneous reduction of bowel movements and rectal release of ECP, bFGF, VEGF and albumin, suggesting that these polypeptides and increased mucosal permeability are important components of the pathophysiology in collagenous colitis.

关键词： Collagenous colitis Inflammatory mediator Steroid treatment Eosinophil cationic protein Basicfibroblast growth factor Vascular endothelial growthfactor

Amylolytic Activity in Selected Sweetpotato(Ipomoea batatas Lam)Varieties during Development and in Storage

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Food and Nutrition Sciences 2012年第5期3卷 660-668页

作者： Agnes Nabubuya Agnes Namutebi Yusuf Byaruhanga Judith Narvhus yngve Stenstrøm Trude Wicklund Department of Food Technology and Nutrition Makerere UniversityKampalaUganda Department of Chemistry Biotechnology and Food ScienceNorwegian University of Life SciencesAasNorway

Sweetpotato varieties (five) were investigated for changes in α- and β-amylase activities during root development and on subjection of harvested roots to different postharvest handling and storage conditions. Changes in α- and β-amylase activities in development were monitored from 10 weeks after planting. At physiological maturity, sweetpotato roots were harvested and subjected to various conditions: freshly harvested roots and cured roots (spread under the sun for four days at 29℃ - 31℃ and 63% - 65% relative humidity), stored at ambient conditions (23℃ - 26℃ and 70% - 80% relative humidity) and in a semi-underground pit (19℃ - 21℃ and 90% - 95% relative humidity). Generally α- and β-amylase activities increased during development with NASPOT 9 and 10 consistently registering the highest activities and NASPOT 1 the lowest activity. Generally, maximum α-amylase activities were achieved at week 3 in ambient stores for NASPOT 9 and NASPOT 10 at 0.930 and 0.897 CU/g, respectively. Maximum β-amylase activity was achieved in ambient stores at week 3 and 4 for fresh and cured NASPOT 9 at 806 and 782 BU/g, respectively. Generally, curing and storing sweetpotatoes in ambient conditions registered the highest amylase activity. Maximum α- and β-amylase activities were registered at 67℃ - 68℃ and 58℃ - 60℃, respectively. These findings provide information for controlled modification of amylase activities of these sweetpotato varieties for product development efforts and monitoring the shelf life of the roots during storage.

关键词： Sweetpotato α-Amylase β-Amylase Development Postharvest Handling Storage

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数字电源解决方案提供更高性能和集成度

中国电子商情 2013年第7期 45-46页

作者： Alexei Zernov yngve Wernqvist Intersil公司

数字电源是一种使用数字信号处理技术来控制功率转换的电源。现在，我们正处在一场由数字电源带来的革命中，数字电源被用于功率转换给电源带来了效率、功率密度、可靠性、稳定性和易用性等重大进步。尽管数字控制概念早在30多年前就已... 详细信息

数字电源是一种使用数字信号处理技术来控制功率转换的电源。现在，我们正处在一场由数字电源带来的革命中，数字电源被用于功率转换给电源带来了效率、功率密度、可靠性、稳定性和易用性等重大进步。尽管数字控制概念早在30多年前就已出现，但我们现在才刚刚开始看到这项技术的广泛使用。

关键词：电源集成度信号处理技术性能数字控制功率可靠性易用性