Corrosion behaviour of micro-plasma arc welded stainless steels in H3PO4 under flowing conditions at different temperatures

[EN] This paper studies the general corrosion behaviour of the micro-plasma arc welded AISI 316L stainless steel in phosphoric acid at different temperatures (25-60°C) and at a Reynolds number of 1456. Galvanic corrosion has been studied using zero-resistance ammeter (ZRA) measurements and polarization curves (by the mixed potential theory). Results show that the microstructure of the stainless steel is modified due to the micro-plasma arc welding procedure. Coupled current density values obtained from polarization curves increase with temperature. ZRA tests present the highest iG values at 60°C; however, the values are very close to zero for all the temperatures studied. This is in agreement with the low value of the compatibility limit and of the parameter which evaluates the importance of the galvanic phenomenon. Both techniques present the most positive potentials at the highest temperature. This study reveals that micro-plasma arc welded AISI 316L stainless steels are appropriated working in the studied H3PO4 media from a corrosion point of view for all the temperatures analysedThe authors would like to express their gratitude to the Spanish MAEC (PCI Mediterráneo C/8196/07, C/018046/08, D/023608/09) and to Asuncion Jaime for her translation assistance.Sánchez Tovar, R.; Montañés Sanjuan, MT.; García Antón, J.; Guenbour, A.; Ben Bachir, A. (2011). Corrosion behaviour of micro-plasma arc welded stainless steels in H3PO4 under flowing conditions at different temperatures. Corrosion Science. 53(4):1237-1246. https://doi.org/10.1016/j.corsci.2010.12.017S1237124653

Convergent evolution of proteins with ankyrin domains the main genomic hallmark of an industrially relevat fungus trichoderma

Die komparative genomische Studie der industriell relevanten Pilze Trichoderma spp. (Hypocreales, Ascomycota) zeigte eine beträchtliche Expansion von Ankyrin-Domäne-enthaltenden- (ANKdc-) Proteinen im Vergleich zu anderen ökologisch ähnlichen Pezizomycotina-Pilzen. Ankyrin- (ANK-) Domäne finden sich in allen Domänen des Lebens als das einzige identifizierbare Strukturmotif oder assoziiert mit anderen PFAM (host) Domänen, die an einer Vielfalt von Funktionen wie Signaltransduktion, Transport, Transkriptionsregulation, Entzündungsantwort und anderen essentiellen Zellprozessen beteiligt sein können. Die Rolle von ANKdc-Proteinen in Pilzen ist noch weitgehend ungeklärt. In dieser Arbeit wurde eine umfassende in silico Analyse der Trichoderma ANKyrome durchgeführt, um die Rolle der Expansion von ANKdc-Proteinen in der Ökologie von Trichoderma spp. zu erforschen und die ersten Hypothesen über ihre Rolle in Trichoderma Interaktomen zu stellen. Ein komparativer genomischer Ansatz wurde für Genom-Mining, Annotierung, Verzeichnis und Klassifizierung von Proteinen mit ANK-Repeats in zehn Trichoderma-Arten verwendet. Insgesamt wurden 18 Hypocreales-Genome nach ANKdc-Proteinen durchsucht und 2406 dieser Proteine gefunden. Unsere Studie zeigte, dass die Expansion von ANKdc-Proteinen nicht ausschließlich bei Trichoderma auftritt, sondern auch bei nahe verwandten Pilzen wie phytopathogenen Nectriaceae und Bionectriaceae. Der Hinweis, dass die Expansion von ANKdc auch für Phytopathogene charakteristisch ist, zwingt dazu, mehr transkriptomische Daten von Trichoderma zu betrachten, wenn sie mit Pflanzen interagieren oder im Boden wachsen, um die Rolle von ANKdc-Proteinen zu verstehen. Durch Orthologie-Inferenz wurden 1172 homologe AKNdc-Proteine auf 183 Orthogruppen verteilt, von denen 18 orthologe ANKdc-Proteine als Core-Proteine in Trichoderma spp identifiziert wurden und 11 als Core-Proteine in allen der 18 betrachteten Hypocreales-Pilzen. Somit zeigen die Ergebnisse, dass der größere Anteil an ANKdc-Proteinen für die meisten Arten einzigartig ist (Orphan). Alle ANK-Repeats in Trichoderma ANKyromen wurden annotiert durch InterProScan in Blast2GO mit drei Datenbanken, Pfam, SMART und Prosite. Darüber hinaus wurden alle Host-Domänen in Trichoderma ANKyromen mit dem gleichen Ansatz, aber mit allen 14 Datenbanken in InterProScan annotiert. Diese Studie ergab, dass die beiden häufigsten Host-Domänen in Trichoderma ANKyromen P-Loop-haltige Nucleosidtriphosphat-Hydrolase und Nucleosidphosphorylase sind, aber auch, dass die Mehrheit dieser ANKdc-Proteine Orphan-Proteine sind. Da bekannt ist, dass Nucleosidphosphorylasen eine Rolle bei Immunantworten spielen, erlauben diese Ergebnisse die Hypothese, dass die Häufigkeit von ANK-Repeats in Trichoderma zur allgemeinen Fitness dieser Gattung beitragen könnte. SignalP- und TMHMM-Analysen zeigten, dass nur ein kleiner Teil vom Trichoderma ANKyrom aus Proteinen die an der Zellsignalisierung beteiligt sind bzw. Transmembranproteinen besteht. Evolutionäre Analysen des Core-ANKyrom von Trichoderma wurden durchgeführt unter der Verwendung von vertikaler Evolution und reinigender Selektion, die in jedem der 18 Core-Proteine in Trichoderma spp. wirkt.The comparative genomics study of the industrially relevant Trichoderma spp. (Hypocreales, Ascomycota) revealed a considerable expansion of ankyrin-domain-containing- (ANKdc-) proteins when compared to other ecologically similar Pezizomycotina fungi. Ankyrin-(ANK-) domains are found in all domains of life as the only identifiable structural motif or as associates of other PFAM (host) domains that may be involved in a diversity of functions such as signal transduction, transport, transcription regulation, inflammatory response and other essential cell processes. The role of ANKdc-proteins in fungi remains poorly understood. In this thesis, a comprehensive in silico analysis of Trichoderma ANKyrome was performed to uncover the role of expansion of ANKdc-proteins in the ecology of Trichoderma spp. and provide the first hypotheses into their role in Trichoderma interactomes. A comparative genomics approach was used for genome mining, annotation, enumeration and classification of proteins with ANK-repeats in 10 Trichoderma species. In total, eighteen Hypocreales genomes were mined for ANKdc-proteins and 2406 of these proteins were retrieved. Our study revealed that the expansion of ANKdc-proteins is not exclusive to Trichoderma, but also evident in closely related fungi such as phytopathogenic Nectriaceae and Bionectriaceae. Indication that expansion of ANKdc is characteristic of phytopathogens as well, compels to look at more transcriptomic data of Trichoderma when interacting with plants or growing in soil to understand the role of ANKdc-proteins. By orthology inference, 1172 homologous ANKdc-proteins were distributed between 183 orthogroups of which 18 orthologous ANKdc-proteins were identified as core in Trichoderma spp. and 11 as core in all of 18 considered Hypocreales fungi. Thus, the results indicate that the larger share of ANKdc-proteins is unique to most species (orphans). All ANK-repeats in Trichoderma ANKyrome were annotated by InterProScan within Blast2GO using three databases, Pfam, SMART, and Prosite. Additionally, all host-domains were annotated within Trichoderma ANKyrome using the same approach but with all 14 databases available in InterProScan. This study revealed that two most frequent host-domains in Trichoderma ANKyrome are P-loop containing nucleoside triphosphate hydrolase and nucleoside phosphorylase, but also that majority of these ANKdc-proteins are orphan proteins. As nucleoside phosphorylases are known to play a role in immune responses, these results allow us to hypothesize that abundance of ANK-repeats in Trichoderma might be contributing to general fitness of this genus. Furthermore, SignalP and TMHMM analyses revealed that only a small share of Trichoderma ANKyrome consists of proteins involved in cell signaling or transmembrane proteins, respectively. Evolutionary analyses of the core Trichoderma ANKyrome were performed using vertical evolution and purifying selection acting across each of 18 core ANKdc-proteins from Trichoderma spp.10

SOCIO-POLITICAL TRANSFORMATION OF PELAGEA WLASSOWA IN BERTOLT BRECHT'S DRAMA „MOTHER”

Brecht was one of the most influential theatre practitioners, playwrights, poets and filmmakers of the 20th century. In this paper we deal with one of his dramas, which was one of his early dramatic writings and which transparently portrays Brecht’s social engagement and his affection for the Communist Party. This drama shows the basic postulates of Marxist ideology and it has received little attention in Serbian scientific literature. This paper points to Brecht’s engagement in this didactic piece, with the support of the theoretical postulates of Shaw, Sartre, Foucault andAdrienne Rich. The aim of the paper is to show the development of the main character, Pelagea Wlassowa, who is undergoing such a transformation, which is inevitably accompanied by her activation in current socio-political events.Publishe

Behaviour of AISI 316L Steel Exposed to Demineralized Water

The subject of investigation was the passivation of AISI 316L austenitic stainless steel. The effectiveness of various passivation media was tested by means of the potentiodynamic polarization technique. Potentiodynamic polarization was carried out in demineralized water before and after passivation treatment. Comparative analysis of the potentiodynamic curves for different passivation media showed that the best protection of the steel surface was provided by a HNO3 solution, φ= 6.0 %, containing CuSO4 · 5H2O, w = 2.0 %. The satisfactory protective properties were found to agree with the high value of the pitting potential

Shape Memory Alloys (Part II): Classification, Production and Application

Shape memory alloys (SMAs) have been extensively investigated because of their unique shape memory behaviour, i.e. their ability to recover their original shape they had before deformation. Shape memory effect is related to the thermoelastic martensitic transformation. Austenite to martensite phase transformation can be obtained by mechanical (loading) and thermal methods (heating and cooling). Depending on thermomechanical conditions, SMAs demonstrate several thermomechanical phenomena, such as pseudoelasticity, superelasticity, shape memory effect (one-way and two-way) and rubber-like behaviour. Numerous alloys show shape memory effect (NiTi-based alloys, Cu-based alloys, Fe-based alloys etc.). Nitinol (NiTi) is the most popular and the most commonly used SMA due to its superior thermomechanical and thermoelectrical properties. NiTi alloys have greater shape memory strain and excellent corrosion resistance compared to Cu – based alloys. However, they are very costly. On the other hand, copper-based alloys (CuZn and CuAl based alloys) are much less expensive, easier to manufacture and have a wider range of potential transformation temperatures. The characteristic transformation temperatures of martensitic transformation of CuAlNi alloys can lie between −200 and 200 °C, and these temperatures depend on Al and Ni content. Among the Cu – based SMAs, the most frequently applied are CuZnAl and CuAlNi alloys. Although CuZnAl alloys with better mechanical properties are the most popular among the Cu-based SMAs, they lack sufficient thermal stability, while CuAlNi shape memory alloys, in spite of their better thermal stability, have found only limited applications due to insufficient formability owing to the brittle γ₂ precipitates. The most important disadvantage of polycrystalline CuAlNi alloys is a small reversible deformation (one-way shape memory effect: up to 4 %; two-way shape memory effect: only approximately 1.5 %) due to intergranular breakdown at low stress levels. The technologies for production of shape memory alloys are induction melting, vacuum melting, vacuum arc melting, following hot and cold working (forging, rolling, wire drawing). In addition, rapid solidification methods, like melt spinning and continuous casting have been developed. These methods are characterized by high cooling rates. High cooling rates allow very short time for diffusion processes and may lead to extremely fine microstructure, better homogeneity etc. SMAs have found applications in many areas due to their thermomechanical and thermoelectrical properties (biomedical applications, engineering industry, electrical industry). In this paper, a review of shape memory alloys, properties and applications of mentioned materials is presented

Fluid States: Performances of Unknowing - The LOG

The LOG is the online edited proceedings of PSi#21 Fluid States: Performances of Unknowing, a festival-style series of conferences, symposia and performances across Asia, Africa, Europe, the Pacific and the Americas throughout 2015, incorporating texts, images, videos and other correspondence and commentary from literally hundreds of the world's top drama, theatre, performance and cultural studies scholars

The effect of protective gas on annealing of 42CrMo4 steel pipes

Translated from Czech (Kovove Mater. 2000 (3) p. 149-159)Available from British Library Document Supply Centre-DSC:9023.190(no 9862)T / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo