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超高强度与普通高强度紧固件钢的组织和性能比较

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水钢科技 2017年第2期 49-62页

作者： Carin Emmy Ingrid Christersdotter OHLUND Mladena LUKOVIC Jonathan WEIDOW Mattias THUVANDER sven erik offerman 高长益刘立德张东升叶雅妮荷兰内德史罗夫科技中心荷兰代尔夫特理工大学材料科学与工程系荷兰代尔夫特理工大学结构工程系瑞典查尔姆斯理工大学应用物理系首钢水钢技术中心贵州六盘水553028

本文比较了14．9级KNDs4超高强度紧固件钢与传统的12．9级34Cr4和10．9级3382紧固件钢的力学性能，结果表明。KNDs4超高强度钢在500℃的高温屈服强度与室温屈服强度的比值比两种传统高强度钢的比值大，并且，当钢的强度较高时。纳米压... 详细信息

本文比较了14．9级KNDs4超高强度紧固件钢与传统的12．9级34Cr4和10．9级3382紧固件钢的力学性能，结果表明。KNDs4超高强度钢在500℃的高温屈服强度与室温屈服强度的比值比两种传统高强度钢的比值大，并且，当钢的强度较高时。纳米压痕的蠕变率较低。与传统高强度钢相比较，KNDS4钢的力学性能改善与KNDS4钢中细小的合金碳化物有关。而且。我们探讨了各种热处理工艺对KNDS4钢的微观组织和硬度变化的影响。对于KNDs4钢而言。改变热处理工艺能使更多的合金碳化物形核生成，使硬度提高8％。并且。标准的热处理工艺使马氏体微观组织更加细小，这对钢的韧性更为有利。除了热处理工艺之外，KNDS4紧固件钢在高温下的力学性能和低的纳米压痕蠕变率充分表明。与传统的高强度紧固件相比，由KNDS4钢制造的紧固件可应用于更高的温度环境。

关键词：马氏体合金碳化物耐热性纳米压痕强度微观组织蠕变

Deteriorated function of cutaneous microcirculation in chronic congestive heart failure

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Journal of Geriatric Cardiology 2011年第2期8卷 82-87页

作者： Marie-Louise Edvinsson erik Uddman sven E Andersson Department of Emergency Medicine Lund University Hospital SE- 221 85 LUND Sweden

Background Chronic congestive heart failure is a complex condition that leads to dysfunction in the peripheral microcirculation. We have previously shown that vascular reactivity is reduced with increasing age. In this study, we examined a group of very old patients with severe chronic heart failure to test the hypothesis that vascular function is further compromised by a combination of heart failure and aging. Methods Cutaneous forearm blood flow was measured by laser Doppler flowmetry and compared among three groups： Group 1 （n = 20, mean ±SE： 85.5 ±4 years）, heart failure patients with New York Heart Association class Ⅳ （NYHA Ⅳ） and with a NT-proBNP level ≥5000 ng/L; Group 2 （n = 15, mean ±SE： 76.5 ±2 years）, heart failure patients with NYHA II and NT-proBNP ≤2000 ng/L, and Group 3 （n = 10, mean ±SE： 67.6 ±3.0 years）, healthy controls with no clinical signs of heart failure. The vasodilator response to the iontophoretic administration of acetylcholine （ACh）, acting via an endothelial mechanism, and sodium nitroprusside （SNP）, acting via a smooth muscle cell mechanism, were studied. Results All patients with heart failure had significantly reduced vascular reactivity independent of the mode of stimulation （ACh, SNP or heat） when compared to healthy controls. However, the responses did not differ between the two groups of heart failure patients. Conclusions Cutaneous vascular reactivity is reduced in heart failure patients and does not correlate with the severity of the condition or age of patients.

关键词： heart failure cutaneous microcirculation endothelial responses acetylcholine smooth muscle responses

A Discontinuous Galerkin Extension of the Vertex-Centered Edge-Based Finite Volume Method

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Communications in Computational Physics 2009年第2期5卷 456-468页

作者： Martin Berggren sven-erik Ekstrom Jan Nordstrom Department of Computing Science Ume˚a UniversitySE-90187 Ume˚a Sweden Division of Scientific Computing Department of Information TechnologyUppsala UniversityBox 337SE-75105 UppsalaSweden

The finite volume(FV)method is the dominating discretization technique for computational fluid dynamics(CFD),particularly in the case of compressible *** discontinuous Galerkin(DG)method has emerged as a promising highaccuracy *** standard DG method reduces to a cell-centered FV method at lowest ***,many of today’s CFD codes use a vertex-centered FV method in which the data structures are edge *** develop a new DG method that reduces to the vertex-centered FV method at lowest order,and examine here the new scheme for scalar hyperbolic ***,the method shows optimal-order accuracy for a smooth linear *** applying a basic hp-adaption strategy,the method successfully handles *** also discuss how to extend the FV edge-based data structure to support the new *** this way,it will in principle be possible to extend an existing code employing the vertex-centered and edge-based FV discretization to encompass higher accuracy through the new DG method.

关键词： Discontinuous Galerkin methods finite volume methods dual mesh vertex-centered edge-based CFD

Brain natriuretic peptide is a potent vasodilator in aged human microcircula- tion and shows a blunted response in heart failure patients

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Journal of Geriatric Cardiology 2014年第1期11卷 50-56页

作者： Marie-Louise Edvinsson erik Uddman Lars Edvinsson sven E. Andersson Department of Emergency and Internal Medicine Institute of Clinical Sciences Lund University Lund University Hospital SE- 221 85 Lund Sweden

Background Brain natriuretic peptide （BNP） is normally present in low levels in the circulation, but it is elevated in parallel with the degree of congestion in heart failure subjects （CHF）. BNP has natriuretic effects and is a potent vasodilator. It is suggested that BNP could be a therapeutic alternative in CHF. However, we postulated that the high levels of circulating BNP in CHF may downregulate the response of microvascular natriuretic receptors. This was tested by comparing 15 CHF patients （BNP 〉 3000 ng/L） with 10 matched, healthy controls. Methods Cutaneous microvascular blood flow in the forearm was measured by laser Doppler Flowmetry. Local heating （＋44°C, 10 min） was used to evoke a maximum local dilator response. Results Non-invasive iontophoretic administration of either BNP or acetylcholine （ACh）, a known endothelium-dependent dilator, elicited an increase in local flow. The nitric oxide synthase inhibitor, l-N-Arginine- methyl-ester （L-NAME）, blocked the BNP response （in controls）. Interestingly, responses to BNP in CHF patients were reduced to about one third of those seen in healthy controls （increase in flow： 251% in CHF vs. 908% in controls; P 〈 0.001）. In contrast, the vasodilator responses to ACh and to local heating were only somewhat attenuated in CHF patients. Thus, dilator capacity and nitric oxide signalling were not af- fected to the same extent as BNP-mediated dilation, indicating a specific downregulation of the latter response. Conclusions The findings show for the first time that microvascular responses to BNP are markedly reduced in CHF patients. This is consistent with the hypothesis of BNP receptor function is downregulated in CHF.

关键词： Heart failure Cutaneous microcirculation Endothelial responses Acetylcholine, Brain natriuretic peptide Nitric oxide

Nutritional and antinutritional compounds in leaves of quinoa

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Food Bioscience 2022年第1期45卷 166-173页

作者： Vasile Stoleru sven-erik Jacobsen Maricel Vitanescu Gerard Jitareanu Monica Butnariu Neculai Munteanu Teodor Stan Gabriel Ciprian Teliban Alexandru Cojocaru Gabriela Mihalache Horticulture Department “Ion Ionescu de la Brad”Iasi University of Life Sciences3 M.Sadoveanu700440IasiRomania Quinoa Quality ApS CVR 40610588Teglværksvej 10DK-4420Denmark Research Institute for Agriculture and Environment 14 M.Sadoveanu700789IasiRomania Chemistry&Biochemistry Department “King Michael I of Romania”Banat’s University of Agricultural Sciences and Veterinary Medicine from TimisoaraCalea Aradului 119300645TimisRomania Integrated Center of Environmental Science Studies in the North Eastern Region(CERNESIM) “Alexandru Ioan Cuza”University of Iasi11 Carol I700506IasiRomania

In the context of climate change,especially for the temperate continental climate,new potential crop species are emerging,originating from the *** of them is quinoa(Chenopodium quinoa Willd.)with multiple benefits for seed and leaf *** is native to South America,grown mainly for seeds,with a high ecological *** is known about the potential of using quinoa plants as a leafy vegetable for food *** this study,the nutritional and antinutritional content of quinoa leaves was evaluated in three cultivars(Titicaca,Puno,Vikinga),considering different densities and times of *** cultivar had a higher total content of carbohydrates,lipids,proteins and dietary fibers,and lower mineral contents in *** levels of antinutrient compounds were found in Vikinga *** the time of the crop establishment,the highest content of primary metabolic compounds(carbohydrates,lipids,proteins,dietary fibers)was achieved by April 17,the sowing *** densities of 7.7,3.2,and 1.6 ***/ha did not significantly influence the content of compounds with antinutritive role,such as oxalates,saponins or trypsin *** content of mineral elements such as:Fe,Zn,Na and K were significantly influenced by the cultivar,compared to Mg and Ca whose values were insignificant regardless of the treatment.

关键词： Chenopodium quinoa Willd. Cultivars Sowing time Plant density Nutritive and antinutritive content

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Ecosystem ecology

Paradoxical prosopagnosia in semantic dementia

丛书名：生态前沿系列

2011年

作者： editor-in-chief sven erik J?rgensen

Includes bibliographical references and index.

ISBN: (数字)9787030303561

ISBN: (纸本)9787894453723

Includes bibliographical references and index.

关键词： Ecological zones.

来源：畅想之星图书光盘版（南... 评论

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Advances in Alzheimer's Disease 2012年第3期1卷 59-67页

作者： sven-erik Fernaeus Per Ostberg Lars-Olof Wahlund Nenad Bogdanovic Department of Neurobiology Care Sciences and Society Karolinska Institutet Stockholm Sweden Department of Neuroscience Uppsala University Uppsala Sweden

Objective: To study episodic and semantic memory for faces and other non-verbal information in semantic dementia (SD). Background: Semantic memory impaired in the rare diagnosis of SD by definition, including knowledge about well- known persons and their appearance. Episodic memory is held to be better preserved. Methods: Two computerized face recognition tests were administered, one measuring episodic memory (Male Faces) and one semantic memory (Political Faces) in addition to a comprehensive test battery. A computerised test of non-verbal semantic memory for national symbols (Euro Flags) was also administered druring the retention interval of the Male Faces test. Results: The SD participants were severely impaired in the episodic face recognition test. In contrast, their performance was in the normal range in Euro Flags and Political Faces, based on knowledge of national political figures. Conclusion: The results are discussed in terms of preserved dynamic memory and severely impaired memory for static facial information in semantic dementia. Research proposals regarding further studies of this paradoxical prosopagnosia in semantic dementia are presented in order to clarify issues regarding static versus dynamic aspects of face memory.

关键词： Face Recognition Semantic Dementia Prosopagnosia Temporal Atrophy

Medial temporal lobe volume predicts rate of learning in Rey-AVLT

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Advances in Alzheimer's Disease 2013年第1期2卷 7-12页

作者： sven-erik Fernaeus Per Julin Ove Almqvist Lars-Olof Wahlund Department of Neurobiology Care Sciences and Society Karolinska Institute Stockholm Sweden

The medial temporal lobe (MTL) has been assigned a central role in human episodic memory and learning. Evidence for this comes from PET and fMRI studies as well as lesion studies. This study aimed at comparing the effect of atrophy at repeated trials of a supraspan test of memory. Included in the study were patients with Alzheimer’s Disease, Mild Cognitive Impairment, and Subjective Memory Disorders as well as Controls (n = 116). The supraspan test used was the Rey Auditory Verbal Learning test (RAVLT). Comparisons between extreme groups with high (Stanine 6 - 9) and low (Stanine 1 - 4) intracranial proportions (IP) of MTL were made at the five trials of RAVLT. There was a significantly higher rate of learning among subjects with high MTL IP compared to those with low MTL IP in both hemispheres. There was no difference in the rate of list learning performance due to education or age and interestingly: the list learning rates among subjects with high/low Lateral Temporal Lobe IPs were almost similar. The hemispheric differences regarding learning rate were small and insignificant. Results are discussed in terms of hippocampal involvement in associative processes necessary in supraspan list learning.

关键词： Hippocampus Learning Medial Temporal Lobe Episodic Memory MRI Atrophy

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应用生态工程 1