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Investigations on the Corrosion Behaviour and Structural Characteristics of Low Temperature Nitrided and Carburised Austenitic Stainless Steel

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材料热处理学报 2004年第5期25卷 311-315页

作者： D. mnter H.-J. Spies H. Biermann chr. Eckstein Department of materials Engineering Technische Universitat Bergakademie Freiberg 09599 Freiberg/ GermanyDepartment of Materials Engineering Technische Universitat Bergakademie Freiberg 09599 Freiberg/ GermanyDepartment of Materials Engineering Technische Universitat Bergakademie Freiberg 09599 Freiberg/ GermanyCorrosion laboratory Steel-Centre-Freiberg (SZF) Research centre of the Technische Universitat Bergakademie Freiberg 09599 Freiberg/ Germany

The wear resistance of austenitic stainless steels can be improved by thermo-chemical surface treatment with nitrogen and carbon. However, it is possible that the corrosion resistance will be impaired by the precipitation of chromiumnitrid or -carbide. The present contribution deals with investigations of the corrosion behaviour and structural characteristics of a low temperature nitrided and carburised austenitic stainless steel. The material investigated was AISI 316L (X2CrNimol7-12-2) austenitic stainless steel. A commercial plasma-nitriding unit (pulsed dc) was used for the nitriding and carburising process. Additional samples were treated by the gasoxinitriding process for a comparison between plasma- and gasoxinitriding. The nitrided and carburised layer of austenitic stainless steel consists of the nitrogen or carbon S-phase (expanded austenite), respectively. X-ray diffraction investigations show the typical shift of the peaks to lower angles, indicating expansion of the fee lattice. Also the X-ray diffraction technique was employed to study the residual stresses in the nitrogen and carbon S-phase. The corrosion behaviour of surface engineered samples was investigated with electrochemical methods. Anodic potentiodynamic polarisation curves were recorded for testing the resistance against general corrosion (in H2SO4) and pitting corrosion (in NaCl).

关键词：奥氏体不锈钢腐蚀低温渗氮低温渗碳残留应力

Analyzing short time series data from periodically fluctuating rodent populations by thresholdmodels: A nearest block bootstrap approach

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Science China mathematics 2009年第6期52卷 1085-1106页

作者： CHAN Kung-Sik TONG Howell STENSETH Nils chr Department of Statistics and Actuarial Science The University of IowaIowa CityIA 52242USA Department of Statistics London School of Economics & the University of Hong KongHong KongChina Centre for Ecological and Evolutionary Synthesis(CEES) Department of BiologyUniversity of OsloP.O.Box 1066 BlindernN-0316 OsloNorway

The study of the rodent fluctuations of the North was initiated in its modern form with Elton's pioneering *** scientific studies have been designed to collect yearly rodent abundance data,but the resulting time series are generally subject to at least two "problems":being short and *** explore the use of the continuous threshold autoregressive(TAR) models for analyzing such *** the simplest case,the continuous TAR models are additive autoregressive models,being piecewise linear in one lag,and linear in all other *** location of the slope change is called the threshold *** continuous TAR models for rodent abundance data can be derived from a general prey-predator model under some simplifying *** lag in which the threshold is located sheds important insights on the structure of the prey-predator *** propose to assess the uncertainty on the location of the threshold via a new bootstrap called the nearest block bootstrap(NBB) which combines the methods of moving block bootstrap and the nearest neighbor *** NBB assumes an underlying finite-order time-homogeneous markov ***,the NBB bootstraps blocks of random block sizes,with each block being drawn from a non-parametric estimate of the future distribution given the realized past bootstrap *** illustrate the methods by simulations and on a particular rodent abundance time series from Kilpisjrvi,Northern Finland.

关键词： AIC continuous threshold autoregressive model non-nested hypotheses partial residual plots 62m10 62P10

morphology of living cells cultured on nanowire arrays with varying nanowire densities and diameters

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Science China(Life Sciences) 2018年第4期61卷 427-435页

作者： Zhen Li Henrik Persson Karl Adolfsson stina Oredsson christelle N. Prinz Division of Solid State Physics Lund University Lund 22100 Sweden Nano Lund Lund University Lund 22100 Sweden Department of Biology Lund 22362 Sweden Present address: Translational & Bioengineering Program Mechanical and Industrial Engineering University of Toronto Toronto MSG 1M1 ON Canada

Vertical nanowire arrays are increasingly investigated for their applications in steering cell behavior. The geometry of the array is an important parameter, which influences the morphology and adhesion of cells. Here, we investigate the effects of array geometry on the morphology of mCF7 cancer cells and mCF10A normal-like epithelial cells. Different gallium phosphide nanowire array-geometries were produced by varying the nanowire density and diameter. Our results show that the cell size is smaller on nanowires compared to flat gallium phosphide. The cell area decreases with increasing the nanowire density on the substrate. We observed an effect of the nanowire diameter on mCF10A cells, with a decreased cell area on 40 nm diameter nanowires, compared to 60 and 80 nm diameter nanowires in high-density arrays. The focal adhesion morphology depends on the extent to which cells are contacting the substrate. For low nanowire densities and diameters, ceils are lying on the substrate and we observed large focal adhesions at the cell edges. In contrast, for high nanowire densities and diameters, cells are lying on top of the nanowires and we observed point-like focal adhesions distributed over the whole cell. Our results constitute a step towards the ability to fine-tune cell behavior on nanowire arrays.

关键词： nanowires cell morphology diameter density aspect ratio

Advances in the development of new biomarkers for Alzheimer’s disease

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Translational Neurodegeneration 2022年第1期11卷 601-624页

作者： Timofey O.Klyucherev Pawel Olszewski Alena A.Shalimova Vladimir N.Chubarev Vadim V.Tarasov misty m.Attwood stina Syvänen Helgi B.Schiöth Department of Neuroscience Functional PharmacologyUniversity of Upp-salaUppsalaSweden Department of Pharmacology Institute of PharmacyI.M.Sechenov First Moscow State Medical UniversityMoscowRussia Institute of Translational medicine and Biotechnology I.M.Sechenov First Moscow State Medical UniversityMoscowRussia Department of Public Health and Caring Sciences Rudbeck LaboratoryUppsala UniversityUppsalaSweden.

Alzheimer’s disease(AD)is a complex,heterogeneous,progressive disease and is the most common type of neurodegenerative *** prevalence of AD is expected to increase as the population ages,placing an additional burden on national healthcare *** is a large need for new diagnostic tests that can detect AD at an early stage with high specificity at relatively low *** development of modern analytical diagnostic tools has made it possible to determine several biomarkers of AD with high specificity,including pathogenic proteins,markers of synaptic dysfunction,and markers of inflammation in the *** is a considerable potential in using microRNA(miRNA)as markers of AD,and diagnostic studies based on miRNA panels suggest that AD could potentially be determined with high accuracy for individual *** of the retina with improved methods of visualization of the fundus are also showing promising results for the potential diagnosis of the *** review focuses on the recent developments of blood,plasma,and ocular biomarkers for the diagnosis of AD.

关键词： Alzheimer’s disease Amyloid beta peptides Biomarkers Blood Cytokines Inflammation microRNA Ocular biomarkers

How Should We Construct mind-Readers？

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Journal of Philosophy Study 2013年第9期3卷 801-822页

作者： Gerhard chr. Bukow m.A. Institute of Philosophy University of Magdeburg Germany

Structured models of kinds of mind-readers are explanatory tools in philosophy and psychology. Structure means that a structure like a theory with certain properties organizes the model of a kind of a reader. Structured models serve to explain mind-reading capabilities in opposition to pure behavior-reading capabilities by explicating properties of the structure that bring on specific capabilities of mind-reading. Typically, grades of fulfilling reading-capabilities are related to grades of rationality. But it is unclear：（1） when we are legitimated to title a reader a mind-reader or behavior-reader, and （2） how the kinds of readers are related with each other （if they can be related by a measure）. I argue that we know a reader if we can construct it and this gives legitimation. But it is unclear how to construct border-cases of readers, for example, minimal mind-readers. Should minimal mind-readers be constructed on the base of ＂reduced＂ mind-readers, or should they be constructed as ＂enriched＂ behavior-readers？ This is the specific question concerning the relations between readers the essay deals with by trying to reduce a maximal mind-reader by Craig-reduction. Because this kind of reduction-method fails, constructing specific kinds of mind-readers needs further research.

关键词： rationality mind-reader construction mind-reading

microsurgical Treatment of Optic Nerve metastasis: Case Report and Review of the Literature

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Case Reports in Clinical medicine 2015年第11期4卷 352-355页

作者： Sl. Kondoff m. milev chr. Tzekov T. Spiriev L. Laleva G. Kirova chr. Kostadionova Department of Neurosurgery Tokuda Hospital Sofia Sofia Bulgaria Department of medical Imaging Diagnostics Tokuda Hospital Sofia Sofia Bulgaria Department of Anesthesiology Tokuda Hospital Sofia Sofia Bulgaria

metastatic lesions to the eye and optic nerve have incidence of 12% and are observed predominantly in patients, diagnosed with breast and lung cancer. However, isolated involvement of the optic nerve by breast cancer metastasis is much rarely reported with only 13 cases reported in the literature by 2013, according to Cherkaev et al., that were often preoperatively misdiagnosed. Herewith we present a rare case of optic nerve metastasis in a previously diagnosed breast cancer patient. Review of the literature was done with analysis of the diagnostic difficulties that these cases present and the role of the neurosurgeon in the management of the patients.

关键词： Optic Nerve metastasis Surgical Treatment Breast Cancer

Asphalt　fractions　in　airborne　particles　from　highway　traffic　and　the　accumulation　in　plants

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Journal of Environmental Sciences 1996年第2期8卷 196-202页

作者： He Kebin(Department of Environmental Engineering, Tsinghua University, Beijing 100084,China)Hans mosbaek Jens chr. Tjell(Department of Environmental Engineering,Technical University of Dentnark, 2800 Lyngby,Denmark) Dept. of Environmental Engineering Tsinghua University Beijing 100084 China Dept. of Environmental Engineering Technical University of Denmark 2800 Lyngby Denmark

With reference to ASTm D4124, asphalt fractions, including polar aromatics (polars),naphthene aromatics (aromatics) and saturates,were characterized both in airborne particles collected in the distances of 2.0 -83.6m from the highway and in the plant samples (including grass,leaves and wheat straw) collected in the distance of 2.0 -10. 0m from the highway. In comparison to the results of diesel particulate, background plant samples and asphalt cernent samples from highway surface, it is concluded that there could be asphalt rnatters in airborne particles and asphalt makes the rnain contributions to the accumulation of the three factions mentioned above in plant species. In the ambient air,the concentrations of the three asphalt fractions are 0. 54- 3.06 ×10-3 mg polars,1. 77- 9. 50 × 10-4 mg aromatics and 0. 21- 1. 23 × 10-4 mg saturates for per cubic meter air. The percentage of bitumen in airborne particles is 1. 61%-11. 02%. In the plant samples, the concentrations are 0. 29- 3.07mg polars, 0.89- 3.89 aromatics and 0. 37-1. 53 mg saturates for per gram dry plant materials.

关键词： asphalt airborne particle traffic pollution HPLC.

高频X线电影摄影在诊断咽、食管疾病中的价值

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放射学实践 1989年第3期4卷 89-96页

作者： chr.Hannig A.Wuttge-Hannig 高起学王虹余力生 Institut für Rntgendiagnostik des Klinikums rechts der Isar cier Technischen Universitt münchen 同济医科大学附属同济医院

本文综述高频X线电影摄影,介绍其所需仪器设备及诊断方法,重点介绍电影摄影诊断咽、食管疾病的适应证及其诊断价值。为了便于更好地理解,还要阐述解剖生理学基础。

关键词：高频X线摄影电影摄影诊断咽

“畸变工程”:从系统的角度探讨零件的畸变现象

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金属热处理 2004年第11期29卷 43-50页

作者： Klaus-DieterThoben DieterKlein Th.Luebben B.Clausen chr.Prinz A.Schulz R.Rentsch R.Kusmierz L.Nowag H.Surm F.Frerichs m.Hunkel P.mayr BremenInstituteofIndustrialTechnologyandAppliedWorkScience（BIBA） BremenGermany InstituteformaterialScience（IWT） BremenGermany

在产品的最终加工过程中用精磨去除零件中的畸变是一个既费钱又费时的事情。例如 ,仅在 (车辆 )传动技术领域 ,1995年德国用于最后精磨以消除工件的畸变而增加的成本已达 8 5亿欧元。迄今为止 ,行业人士认为在最后的产品加工过程中导致... 详细信息

在产品的最终加工过程中用精磨去除零件中的畸变是一个既费钱又费时的事情。例如 ,仅在 (车辆 )传动技术领域 ,1995年德国用于最后精磨以消除工件的畸变而增加的成本已达 8 5亿欧元。迄今为止 ,行业人士认为在最后的产品加工过程中导致零件产生畸变的主要原因在于淬火过程 ,而今大家普遍认为这个观点不是很对 ,认为淬火过程只是释放了在各个加工环节中积累在工件中的畸变潜能 ,如铸造、车削加工、铣削、淬火、磨削。由不来梅大学创立及DeutscheForschungsgemeinschaft资助的合作研究中心SFB 5 70“畸变工程”的研究方针是从系统导向着手 ,分析零件的畸变。合作研究中心由 12个子项目组成 ,涉及 2 0多位来自材料科学、制造技术、数学及过程控制工程的研究人员。根据系统导向的方法 ,合作研究中心SFB 5 70“畸变工程”认为 ,与优化零件整个生产过程 (工序链 )相比 ,对零件生产过程中的单个过程的优化是第二位的。为了推广系统导向的方法 ,保证SFB 5 70“畸变工程”中集中在不同工序和技术的这 12个子项目间的一个连续、协调的知识和信息交换 ,已成立了一个系统模式工作组。这个工作组的焦点在于详细阐述和进一步发展系统导向的方法以及协调应用于这些子项目中的工序和方法。和其它方法相比较 ,整体方法包?

关键词：变现工程项目系统欧元协调行业导向潜能数学