Dynamic axial crushing of square tubes

Eighty-four dynamic tests on thin-walled square steel tubes having two different cross-sections with c/h = 30.25 and c/h = 32.18 and various lengths were crushed axially on a drop hammer rig. Approximate theoretical predictions were developed for the axial progressive crushing of square box columns using a kinematically admissible method of analysis. This theoretical study predicts four deformation modes which govern the behaviour for different ranges of the parameter c/h. New asymmetric deformation modes were predicted theoretically and confirmed in the experimental tests. These asymmetric modes cause an inclination of a column which could lead to collapse in the sense of Euler even for relatively short columns. The effective crushing distance is considered in the approximate theoretical analysis together with the influence of material strain rate sensitivity, which is important for steel even when the loadings are quasi-static. The simple equations presented herein for the design of axially crushed spuare box columns give reasonable agreement with the corresponding experimental results.     

Die Verdampfung des Eisens und seiner Begleitelemente Kupfer und Mangan beim Schwebeschmelzen unter vermindertem Druck

Beschreibung einer Schwebeschmelzanlage für das tiegelfreie Schmelzen von Metallen unter kontrollierter Gasatmosphäre. Untersuchung der Verdampfung des Eisens und der Begleitelemente Kupfer und Mangan aus Proben des Stahles X 5 CrNi 18 9 in eine Argonatmosphäre bei Drücken zwischen 760 und 5 · 10^?2 Torr und Schmelztemperaturen zwischen 1760 und 1930 °C. Deutung der Versuchsergebnisse anhand eines Ansatzes von E. T. Turkdogan für die Diffusion von Metalldampf durch eine laminare Strömungsgrenzschicht. Vergleich der Ergebnisse für die Verdampfung unter vermindertem Druck in der Schwebeschmelzanlage und im Vakuuminduktionsofen und Schlußfolgerungen für die Einstellung optimaler Bedingungen zur Entfernung von Kupfer aus Stahlschmelzen.     

A versatile toolbox for PCR-based tagging of yeast genes: new fluorescent proteins, more markers and promoter substitution cassettes

Tagging of genes by chromosomal integration of PCR amplified cassettes is a widely used and fast method to label proteins in vivo in the yeast Saccharomyces cerevisiae. This strategy directs the amplified tags to the desired chromosomal loci due to flanking homologous sequences provided by the PCR-primers, thus enabling the selective introduction of any sequence at any place of a gene, e.g. for the generation of C-terminal tagged genes or for the exchange of the promoter and N-terminal tagging of a gene. To make this method most powerful we constructed a series of 76 novel cassettes, containing a broad variety of C-terminal epitope tags as well as nine different promoter substitutions in combination with N-terminal tags. Furthermore, new selection markers have been introduced. The tags include the so far brightest and most yeast-optimized version of the red fluorescent protein, called RedStar2, as well as all other commonly used fluorescent proteins and tags used for the detection and purification of proteins and protein complexes. Using the provided cassettes for N- and C-terminal gene tagging or for deletion of any given gene, a set of only four primers is required, which makes this method very cost-effective and reproducible. This new toolbox should help to speed up the analysis of gene function in yeast, on the level of single genes, as well as in systematic approaches.     

安全控制器为智能卡安全效力

智能卡安全控制器经常遭受黑客的攻击，最近攻击方法的巨大改进，宣布了以前许多设计声称其产品非常安全的说法的终结。对于原本设计具有很长设计寿命的用于护照之类的高安全性芯片来说，现在也不得不采取最新的反制措施来应对，而需要接受最广泛的各种测试。     

Spontaneous formation of gold microplates during reduction‐coupled removal of noble metals using Dowex M4195 resin

The present work reports the novel phenomenon of spontaneous formation of gold microplates. The effect is observed as a consequence of , , , and sorption on the Dowex M4195 resin. Therefore an attempt to explain the phenomenon mechanism is made. The research is covering sorption, kinetic and thermodynamic studies. The shapes of formed gold single plates are determined. The uptakes of Au(III), Pt(IV), Pd(II), and Re(VII) tests have been conducted using a batch method from single‐component metals solutions in 0.1M HCl. The sorption‐reduction phenomenon has been assessed by executed SEM, FTIR, XRD, and XPS studies. The greatest sorption capacity, combined with reduction‐coupled removal phenomenon, has been achieved for gold (5.5 mmol Au·g^?1 at 9°C). Executed SEM and XRD analyzes prove formation of gold single crystals during present process, furthermore reduction of rhenium is indicated by XPS analysis. Based on the obtained FTIR and Raman's spectra, the reduction phenomenon is probably followed by resins’ functional groups oxidation. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42425.     

The sensor effect tetrahedron: an extended transducer space

A visualisation of a four-dimensional space called an information and energy tetrahedron is introduced in the paper. This model of energy and information could be found useful by designers and developers of new measuring devices as well as in the analysis of measurement and instrumentation systems. The tetrahedron concept is an extension of the idea of a three dimensional transducer space first presented more than 30 years ago. By taking account of the interference sources within the range of possible energy forms it extends the three dimensional predecessor, which did not encompass these effects. To obtain this extended tetrahedron model, the sensor is viewed from its boundary perspective using the principles of systems engineering developed for application in measuring systems. When this approach is applied to sensors it is shown that they may be reduced to systems influenced by three classes of inputs. These inputs, which consist of the information borne by the measurand in its specific energy form, the support energy form and the contaminating information and energy forms, are shown to constitute what is called the input triangle in the paper. The system output, which is an information bearing energy form, provides an axis normal to the plane formed by the input triangle. All of the axes are drawn based upon the COMETMAN acronym to represent the diversity of possible energy domains. A summary of different ways of classifying energy forms or domains, which is given in the paper, allows these different methods of grouping to be compared. The application of the sensor effect tetrahedron is placed within the context of measurement by means of the three interfaces between humans, machines and their working environment. Introducing extrinsic and intrinsic boundaries permits the link between sensors and formal metrological components to be established. In this way the paper can help to provide a deep perception of sensors.     

OXIDE METALLURGY-ITS PURPOSES AND PRACTICAL APPROACHES

1.IntroductionNonmetallicinclusionssuchasoxides,sulfides,oxysulphides,nitridesandcarbonitridesareharmfultosteelservicepropertiesaccordingtotheconventionalviewandexperience.Theincreasingdemandsforqualityofsteelnecessitateacurrentimprovementofsteelcleanlless.Manyeffortshavebeenundertakentoremoveoxidealldsulfideinclusiollsbysecondarymetallurgy,tundishmetallurgyandladlemetallurgyandsomespecialmethodssuchasfiltrationduringthecastingprocesslll.However,theeliminationofnonmetallicinclllsiollscanneverb…