δ/γ Interface bondary sliding as a mechanism for strain accommodation during hot deformation in a duplex stainless steel

In the present work, the mechanical properties and the microstructural evolution of a duplex stainless steel in the as-cast and wrought conditions during deformation under hot-working conditions have been studied. Hot torsion tests, at strain rates of = 1 s⁻¹, have been carried out using prepolished samples on which surface parallel scratches have been practiced. The observation of the surface of the samples shows a large displacement of the scratches produced by two different mechanisms, sliding on the δ/γ interface, and shearing of the ferrite. The displacements in the as-cast condition have been found to concentrate in a reduced set of ferrite/austenite interfaces leading to the formation of cracks along them. In the wrought material, the distribution of the sliding is more homogeneous over all the ferrite/austenite interfaces, and no damage has been produced. These behavioral differences between both materials have been related in the present work, to the characteristics of the corresponding microstructures, to the spatial phase distribution, and to the nature of the ferrite/austenite interface, among others.     

Skin colour assessment in safety testing of cosmetics. An overview

Synopsis
Few subjects are as problematical to dermatologists, cosmetologists and related experimenters involved in safety testing as the clinical assessment of skin colour. At the core of the problem is the word erythema, which does not communicate a sense for the nuance of red. In addition, light shades of red are not visible in dark-skinned people. Human assays aiming at evaluating the irritancy and allergic potential of cosmetics take advantage to use instrumental assessments of skin colour. However, there are pitfalls related to the complex biological aspects of the cutaneous reactivity, to the design of the in vivo assay, and to technical aspects bound to the principle of the measuring methods. Sound information can only be reached when these concerns are solved.
Résumé
Peu de sujets sont aussi problématiques pour les dermatologues, cosmétologues et autres expérimentateurs impliqués dans les tests de sûreté que l'évaluation clinique des couleurs cutanées. Au centre du problème est le mot érythème qui ne communique pas la notion des nuances de rouge. De plus, un érythème discret peut ne pas être visible chez des individus à la peau foncée. Les tests humains visant àévaluer les potentialités d'irritation et d'allergie aux cosmétiques bénéficient des évaluations instrumentales de la couleur cutanée. Cependant, il existe des pièges liés aux aspects biologiques complexes de la réactivité cutanée, au choix du test in vivo et à des aspects techniques en relation avec le principe du système de mesure. Une information adéquate ne peut être obtenue qu'après avoir résolu ces problèmes.     

Nucleation in Dilute 3He-4He Liquid Mixtures at Low Temperatures

We present a study of phase separation from supersaturated ³ He- ⁴ He liquid mixtures at low temperatures addressing both the degree of critical supersaturation x_cr and the thermal-to-quantum crossover temperature T* for the nucleation process. Two different nucleation seeds are investigated, namely ³ He droplets and ⁴ He vortex lines with cores filled with ³ He. We have found that the experimental T* is reproduced when we consider that nucleation proceeds from ³ He droplets, whereas x_cr is reproduced when we consider ⁴ He vortex lines filled with ³ He. However, neither nucleation configuration is able to simultaneously reproduce the current experimental information on x_cr and T*.     

Pharma clinics. How I treat...or preventing pain with "patches"]

There exists two distinct types of patches aiming at increasing the pain threshold either systematically or locally. The first type of analgesic patch is a real transdermal delivery system releasing fentanyl. Such potent opioid drug exerts a systemic effect. The other type of patch associates lidocain and prilocain to induce a local anesthesia of the skin without inducing a systemic effect.     

Ring Vortex Destabilization in Supersaturated 3He-4He Liquid Mixtures at Low Temperatures

The effect of ring vortices on the destabilization of supersaturated liquid helium mixtures at very low temperatures is investigated as a function of pressure. We have found that large ring vortices trigger the segregation of ³ He at smaller values of the concentration than small ring vortices. Our calculations indicate that the existence of ring vortices in the mixture is a possible mechanism to understand the rather small degree of critical super-saturation found in the experiments.     

Structural characterization of chromosome I size variants from a natural yeast strain

Many yeast strains isolated from the wild show karyotype instability during vegetative growth, with rearrangement rates of up to 10(-2) chromosomal changes per generation. Physical isolation and analysis of several chromosome I size variants of one of these strains revealed that they differed only in their subtelomeric regions, leaving the central 150 Kb unaltered. Fine mapping of these subtelomeric variable regions revealed gross alterations of two very similar loci, FLO1 and FLO9. These loci are located on the right and left arms, respectively, of chromosome I and encompass internal repetitive DNA sequences. Furthermore, some chromosome I variants lacking the FLO1 locus showed evidence of recombination at a DNA region on their right arm that is enriched in repeated sequences, including Ty LTRs. We propose that repetitive sequences in many subtelomeric regions in S. cerevisiae play a key role in karyotype hypervariability. As these regions encode several membrane-associated proteins, subtelomeric plasticity may allow rapid adaptive changes of the yeast strain to specific substrates. This pattern of semi-conservative chromosomal rearrangement may have profound implications, both in terms of evolution of wild strains and for biotechnological processes.     

基于Linux和MiniGUI的智能焊接 控制器界面设计与实现

在简要介绍MiniGUI图形用户界面系统的体系结构和特点的基础上,详细介绍了MiniGUI图形用户界面系统在ARM-Linux下的移植,以及智能焊接控制器界面的框架结构和编程实现。实际应用表明,该界面操作简单、灵活友好、提高了系统的整体性能。     

Tuning the optical properties of alloyed CdSexS1 − x nanoparticles by changing the constituent stoichiometry

The spherical particles CdSe_xS_1 − x with 30-80 nm in radius have been successfully prepared by the hydrothermal reaction at 200 °C. The structure characterization which has been carried out using X-ray diffraction (XRD) shows hexagonal crystal structure. Novel properties have been observed via UV-visual absorption spectra and photoluminescence (PL) spectra. The absorption shoulder and the luminescence emission peaks have been tuned by changing the mole ratio of Se in the CdSe_xS_1 − x samples.     

基于无速度传感器的高转矩软起动器的研究

本文对无速度传感器的软起动器进行了深入剖折，所研究的软起动器具备四种起动方式：电压斜坡起动、限流起动、转速斜坡起动和分级变频起动。提出了基于无速度传感器的分级变频高转矩异步电机软起动方案。研制出基于80C196KC单片机控制的无速度传感器的分级变频高转矩软起动器。该软起动器具有结构简单，起动转矩大，能实现速度闭环控制的优点，使软起动器控制技术提高了一步，并且有持续研究开发的前景，有望在较广泛的应用领域得到推广应用。