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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
321

Traitement de la matière active d’accumulateurs Ni-Cd en fin de vie par couplage électrolixiviation/électrodéposition / Treatment of active matter coming from end-of-life Ni-Cd batteries by coupling elctroleaching/electrowinning

Hazotte, Claire 05 December 2014 (has links)
Ce mémoire porte sur le développement d'un protocole d'extraction sélective de métaux présents dans les accumulateurs Ni-Cd en fin de vie. Classiquement, les procédés hydrométallurgiques appliqués à ce type de solides comportent de nombreuses étapes dont les principales sont la lixiviation et la récupération du métal par électrolyse. Le procédé utilisé permet le couplage des opérations d'Electrolixiviation et d'Electrodéposition (noté E/E) au sein d'une même cellule. La technique est basée sur la lixiviation de la matière active des accumulateurs Ni-Cd par les protons générés à l'anode, les cations lixiviés (Co2+, Ni2+ et Cd2+) migrent vers la cathode où le cadmium est sélectivement réduit. Nous avons étudié les possibilités de récupération des métaux, mais également tenté d'appréhender les phénomènes prenant place dans la cellule lors du couplage E/E. Dans un premier temps, nous avons choisi de démanteler manuellement des accumulateurs en raison de la complexité des broyats industriels. La matière active des accumulateurs Ni-Cd a été caractérisée. Sa composition moyenne est la suivante :Cd(OH)2 : 45,3 %, Cd0 : 0,02 %, Ni(OH)2 : 30,0 %, Ni0 :12,9 %, NiOOH : 0,9%, Co(OH)2 : 2,4 %. Au vu des différentes formes minéralogiques présentes, ce solide peut être considéré comme un déchet modèle pour ce traitement. Avant d'envisager le couplage E/E, la lixiviation chimique de la matière active par H2SO4 a d'abord été étudiée. La modélisation de cette opération a mis en évidence que la cinétique de dissolution de Cd(OH)2 est gouvernée par le transfert de masse des protons, la dissolution de Ni(OH)2 et Co(OH)2 étant quant à elle régie par la réaction chimique de surface. Dans ces conditions de lixiviation douce, le nickel métallique n'est pas oxydé et se retrouve dans le résidu solide avec le carbone. Nous avons pu démontrer ensuite la sélectivité de l'électrodéposition vis-à-vis du Co2+ et du Ni2+ avec un rendement faradique d'environ 99 % à une densité de courant de 350 A.m-2. L'étude cinétique de l'E/E a montré que l'électrolixiviation est l'étape limitante du procédé, phénomène qui a également été modélisé. L'E/E appliquée aux matériaux d'électrodes permet en 5 h 30 de lixivier 97 % du cadmium initialement présent. Le solide résiduel est composé à 82 % de nickel, principalement sous la forme métallique, 4 % de cadmium, 0,5 % de cobalt et 3 % de carbone. Le dépôt de cadmium est obtenu avec une pureté supérieure à 97 % et un rendement faradique de déposition supérieur à 74 % à une densité de courant de 350 A.m-2. La faisabilité du couplage E/E appliqué au traitement d'accumulateurs Ni-Cd en fin de vie a été démontrée malgré la complexité de la matrice. Les premiers essais d'application de ce traitement à des échantillons industriels (Cd(OH)2 : 36,1 %, Ni(OH)2 : 24,1 %, Ni0 : 16,6 %, NiOOH : 5,5 %, Co(OH)2 : 2,4 % et Fe :1% en masse) confirment les résultats obtenus avec les matériaux d'électrodes provenant du démantèlement manuel / This thesis focuses on the development of a protocol for selective extraction of metals from spent Ni-Cd batteries. Conventionally, hydrometallurgical processes applied to this type of solids involve several steps, the main ones being the leaching and the metal recovery by electrolysis. The method used consists in coupling Electroleaching to Electrodeposition operation (denoted E/E) within the same cell. The technique is based on the leaching of the active material of Ni-Cd batteries by protons generated at the anode: the cations (Co2+, Ni2+ and Cd2+) released by leaching migrate to the cathode where the cadmium is selectively reduced. We studied the possibility of metals recovery, but also tried to understand the phenomena occurring in the cell during the E/E experiments. Initially, it was preferred to manually dismantle batteries due to the complexity of industrial waste crushed. The active matter of Ni-Cd has been characterized. Its average composition is as follows: Cd(OH)2: 45.3%, Cd0: 0.02%, Ni(OH)2: 30.0%, Ni0: 12.9%, NiOOH: 0.9%, Co(OH)2: 2.4%. In view of these different mineralogical forms, this solid can be considered a model for the waste treatment. Before considering the E/E treatment, chemical leaching of the active matter by H2SO4 was first studied. Modelling of the tests carried out showed that the kinetics of Cd(OH)2 dissolution is governed by mass transfer of protons and the dissolution of Ni(OH)2 and Co(OH)2 by the surface chemical reaction. Under these conditions of soft leaching, metal nickel is not oxidized and is found in the solid residue, with carbon. We had to demonstrate the cadmium electrowinning selectivity, for separation from Co2+ and Ni2+ species, with a current efficiency up to 99% at a current density of 350 A.m-2. The kinetic study of the E/E showed that electroleaching is mainly governed by H+ generation at the anode. Besides, the overall process is largerly controlled by cations transport from the anode to the cathode side: this transport phenomenon had also been modeled. The E/E applied to the electrode materials for 5 h 30 allows the leaching of 97% of the cadmium initially present. The residual solid is composed by 82% of nickel, mainly in the metallic form, 4% of cadmium, 0.5% of cobalt and 3% carbon. The deposition of cadmium is obtained with a purity greater than 97% and a current efficiency greater than 74% at a current density of 350 A.m-2. The feasibility of the E/E coupling applied to the spent Ni-Cd batteries treatment has been demonstrated despite the complexity of the matrix. The first tests to apply this treatment to industrial samples (Cd(OH)2: 36.1% Ni(OH)2: 24.1% Ni0: 16.6% NiOOH: 5.5% Co(OH)2: 2.4% and Fe: 1% by weight) confirm the results obtained with the electrode material from the manual dismantling
322

Parallel computer simulation of highly nonlinear dynamics of polymer solutions in benchmark flow problems

Yang, Wenjing January 2014 (has links)
Simulation of viscoelastic fluid flows in complex geometry at high Weissenburg (Wi) number is still a challenging problem in computational rheology. In this thesis, parallel computing toolbox available in OpenFOAM has been analysed in details. The scalability of parallel viscoelastic flow solver has been critically evaluated under benchmark flow problems, including 2D and 3D 4:1 contraction flow, 2D flow past a cylinder with 50% blockage, using up to 4096 CPU cores and 55 million computational grids. Areas for further improvements in parallel computational rheology are discussed. A new monitoring and preserving molecular conformation method is proposed to overcome the unphysical artefact problem in simulation of the FENE-CD-JS model under benchmark flow problems. It greatly enhances the stability of parallel viscoelastic flow solver in simulation of high Wi number flows and, for the first time, successfully captures elastic turbulence in flow past a cylinder problem. A new constitutive model, named as FENE-CD2-JS model, is proposed to overcome the existing shortcomings of the original FENE dumbbell model. The model accounts for high order interactions between non-equilibrium polymer chain molecules and could reproduce the asymmetric oscillatory vortex dynamics in the 16:1 contraction flow geometry at high Wi number (up to 48) flow observed in the experiments. For the first time, the analysis of the spatial distribution of non-equilibrium polymer conformation, through the conformational tensor, in strong complex flow and the results of their power-law scaling are also presented.
323

Vypovídací schopnost účetních závěrek sestavených dle českých pravidel a IFRS / Financial statements based on IFRS and CZ GAAP and their reporting value

Machala, Marek January 2014 (has links)
The thesis deals with comparison of financial statements based on IFRS and CZ GAAP. In the theoretical part fundamental principles of both accounting systems are described and typical differencies between IFRS and CZ GAAP are specified. In the practical part financial statements of a chosen company reporting in both systems are analyzed. Using balance sheet and income statemet analysis both structure of the statements and value of particular items published in the statements are assessed. Analysis of ratio indicators and EVA explains why selected indicators differ depending on chosen accounting system.
324

Introducing DevOps methods and processes for an existing organization

Samuelsson, Love January 2021 (has links)
DevOps is a cultural idea rather than a firm way to do software development, with the aim of reducing software lead times by bringing operations and development closer via principles that mainly deal with automation. This paper provides a potential DevOps solution for Wexnet, an internet service provider company. A requirements list is created by interviewing which is then used to evaluate existing web-based git solutions. Two viable candidates were selected, GitHub and GitLab which were compared against each other. GitLab was chosen because of its comparably low resource usage and lower overall setup complexity.
325

Metavinculin: Neue Erkenntnisse der funktionellen Eigenschaften eines Muskeladhäsionsproteins

Thoß, Florian 02 March 2015 (has links)
In mehrzelligen Organismen ist der Aufbau stabiler Zell-Zell- und Zell-Matrix-Verbindungen lebensnotwendig. Hierfür werden innerhalb einer Körperzelle membranständige Adhäsionskomplexe gebildet, die eine zentrale Rolle in der Verankerung sowie Regulierung des intrazellulären Zytoskelettes spielen. Zu diesen Aktin-bindenden Proteinen gehören das ubiquitär vorkommende Vinculin sowie dessen muskelspezifische Spleißvariante Metavinculin, deren genaue Funktion bisher nicht bekannt ist. Metavinculin besitzt einen Einschub von zusätzlichen 68 Aminosäuren im Vergleich zu Vinculin, wodurch eine neue alpha-Helix H1´ im Bereich der Schwanzdomäne entsteht, die dem Protein funktionelle Unterschiede verleiht. Frühere Studien zeigten, dass eine Punktmutation innerhalb des Metavinculin-spezifischen Einschubes (Mutante R975W) mit dem Auftreten einer familiären dilatativen Kardiomyopathie assoziiert ist. In der vorliegenden Arbeit wurden biochemische und zellbiologische Versuche sowie immunhistochemische Untersuchungen durchgeführt, welche bisher unbekannte Eigenschaften des Metavinculins aufdecken und Hinweise zur physiologischen Funktion des Metavinculins in muskulären Zelladhäsionsverbindungen liefern. Es konnte in der Rindermuskulatur gezeigt werden, dass Metavinculin eine fasertypabhängige Expression aufweist, welche unabhängig vom verwendeten Muskeltyp reproduzierbar auftritt. Metavinculin wird im Gegensatz zum ubiquitär vorkommenden Vinculin in den Muskeladhäsionskomplexen vor allem schneller, glykolytischer Muskelfasertypen ausgebildet. Untersuchungen zur Proteindynamik zeigten eine deutlich verlängerte Verweildauer von Metavinculin im Vergleich zu Vinculin in den Adhäsionskomplexen von Muskelvorläuferzellen. In CD-spektroskopischen Untersuchungen konnte eine deutliche Destabilisierung der Schwanzdomäne der Metavinculin-Mutante R975W im Vergleich zum Wildtyp aufgezeigt werden. Insgesamt deuten die Ergebnisse darauf hin, dass der zusätzliche Einbau von Metavinculin in die Adhäsionskomplexe von Muskelfasern eine spezielle Anpassung an die physiologische Funktion und mechanische Belastung der Muskelfasern ist und wahrscheinlich eine höhere mechanische Stabilität bei schnellen und glykolytischen Muskelfasertypen gewährleistet. Wird die Stabilität der Aktin-bindenden Domäne in Metavinculin durch eine Punktmutation vermindert, könnte dies zu einer weniger stabilen Verankerung des Aktinzytoskelettes führen, was zu den pathophysiologischen Veränderung des Herzmuskels im Rahmen einer dilatativen Kardiomyopathie beitragen kann.:1 Einleitung……………………………………………………………………......................... 5 1.1 Allgemeine Einleitung……....…………………………………........................... 5 1.2 Die Adhäsionsproteine Metavinculin und Vinculin…......................... 5 1.2.1 Bedeutung und Vorkommen………………………………...........................5 1.2.2 Aufbau, Struktur und Bindungspartner………………......................... 7 1.2.3 Unterschiede in Aufbau und Funktion zwischen Metavinculin und Vinculin ... 8 1.2.4 Unterschiede der Dynamik im Adhäsionskomplex………………............8 1.3 Metavinculin in der Muskulatur………………………………..........................9 1.3.1 Allgemeines………………………………………………………………………………………. 9 1.3.2 Aufbau und Einteilung verschiedener Muskeltypen……………………….. 10 1.3.3 Skelettmuskelfasertypen……………………………………………………………...… 11 1.3.4 Dilatative Kardiomyopathie bei Mutationen im Metavinculingen…12 1.3.5 Ungleiche Verteilung von Metavinculin in verschiedenen Muskeltypen... 13 1.4 Zielstellung der Arbeit………………………………………………………………….. 14 2 Publikation - Metavinculin: New insights into functional properties of a muscle adhesion protein… 15 3 Zusammenfassung…………...........…………………………………………………… 24 4 Anhang……………………………………………...……………………………………………. 29 Material und Methoden………………………………………………..…………………….. 29 Literaturverzeichnis……………………………………………………….…………………… 33 5 Erklärung über die eigenständige Abfassung der Arbeit…………………36 6 Lebenslauf……………………………………………………………………………………….. 37 7 Danksagung……………………………………………………………………………………… 39
326

Performance of DevOps compared to DevSecOps : DevSecOps pipelines benchmarked!

Björnholm, Jimmy January 2020 (has links)
This paper examines how adding security tools to a software pipeline affect the build time. Software development is an ever-changing field in a world where computers are trusted with almost everything society does. Meanwhile keeping build time low is crucial, and some aspects of quality assurance have therefore been left on the cutting room floor, security being one of the most vital and time-consuming. The time taken to scan for vulnerabilities has been suggested as a reason for the absence of security tests. By implementing nine different security tools into a generic DevOps pipeline, this paper aimed to examine the build times quantitatively.              The tools were selected using the OWASP Top Ten, coupled with an ISO standard, as a guideline. OWASP Juice Shop was used as the testing environment, and the scans managed to find most of the vulnerabilities in the Vulnerable Web Application. The pipeline was set up in Microsoft Azure and was configured in .yaml files. The resulting scan durations show that adding security measures to a build pipeline can add as little as 1/3 of the original build time.
327

Complex structures in the Au – Cd alloys: electron origin of diffusion ordering

Afonikova, N.S., Degtyareva, V.F. 14 September 2018 (has links)
No description available.
328

The core problems of globally distributed work in software development environments, and possible solutions : DevOps environments' opportunities for better adoption of a globally distributed working culture

Oachesu, Alex, Negovanovic, Nemanja January 2021 (has links)
Both distributed work and DevOps are on an upward trend. There is a slight resemblance between the problems that DevOps is trying to find answers to, the solutions, and the common problems that geographically distributed work faces. Mainly, they are related to isolated environments that have difficulties in mutual understanding and communication, collaboration. All this leads to inefficiencies and costs that affect the overall efficiency of companies. This report identifies how DevOps engineering principles and implementations provide solutions to common problems in globally distributed work environments. It uses a literature systematic literature search and review to extract the recent and relevant academic data in the scope of the two research questions. Then, a proof-of-concept is implemented for DevOps, which confirms the literature. In parallel, a survey addressed to Swedish companies provides subject-related data from the professional environment, which largely supports the literature and brings extra knowledge. All of this is considered in data analysis and formulation of conclusions, showing DevOps features that can improve and support work in globally distributed environments and outlining the importance of the tailored organizational culture for the modern need of large-scale distributed work.
329

Charakterisierung bi- und trispezifischer anti-CD40 Antikörper-Fusionsproteine / Characterization of bi- and trispecific antiCD40 antibody fusion proteins

Pauschinger, Christoph Johannes January 2022 (has links) (PDF)
Das Immunsystem zu aktivieren, um eine körpereigene Immunantwort gegen Tumorzellen hervorzurufen, ist ein innovativer Therapieansatz. Eine vielversprechende Zielstruktur hierfür ist CD40, ein Mitglied der TNFRSF- Familie und starker Stimulator Antigen-präsentierender Zellen. Die TNFRSF-Rezeptor Aktivierung ist abhängig von der Bildung oligomerer (TNFSF3-TNFRSF3)2 Komplexe, was insbesondere durch entsprechende räumliche Ausrichtung membranständiger Liganden und deren hohe lokale Konzentration im Zell-Zell-Kontakt gewährleistet wird. Im Rahmen dieser Arbeit wurde die (TNFSF3-TNFRSF3)2 Komplexbildung mittels membranständiger Liganden durch die Generierung von CD40-spezifischen Antikörper-Fusions- proteinen imitiert, die über zusätzliche Bindedomänen, single chain fragment variable (scFvs), für zellständige Zielstrukturen (CD70, BCMA, PDL1) verfügen. Dazu wurden die schweren und/oder leichten anti-CD40 Antikörperketten C-terminal mit einem scFv-Fragment verknüpft und dadurch verschiedene CD40-spezifische Antikörper-Fusionsproteine mit scFv-Fragmenten generiert. Die Funktionalität dieser besonderen Antikörper-Fusionsproteine wurde hinsichtlich ihrer Bindungsfähigkeit mittels Gaussia princeps Luciferaseassay und hinsichtlich ihres Agonismus über den Nachweis der Interleukin-8 Induktion per ELISA analysiert. Dabei zeigte sich, dass die CD40-Aktivierung durch die an den Antikörper-Fusionsproteinen verankerten scFv-Domänen bei einem Großteil potenziert werden konnte, wenn diese die entsprechenden Zielantigene CD70, BCMA, PDL1 binden. Des Weiteren waren hinsichtlich ihres Agonimsus die Antikörper-Fusionsproteine mit einer scFv-Domäne an der schweren oder an der leichten Antikörperkette den Antikörper-Fusionsproteinen überlegen, die scFv-Domänen an beiden Antikörperketten aufwiesen. Dennoch stellen auch letztere eine vielversprechende Therapievariante dar, da sie aufgrund ihrer breiteren Spezifität verschiedene Tumorantigene binden können. Die in dieser Arbeit produzierten und charakterisierten CD40-spezifischen Antikörper-Fusionsproteine aktivieren das Immunsystem gezielter in dem Gewebe, in dem vermehrt spezifische Tumorantigene exprimiert werden. Dadurch eröffnen sie neue Möglichkeiten in der Tumortherapie. / Activating the immune system to induce an endogenous immune response against tumor cells is an innovative therapeutic approach. A promising target structure for this is CD40, a member of the TNFRSF family and potent stimulator of antigen-presenting cells. TNFRSF receptor activation is dependent on the formation of oligomeric (TNFSF3-TNFRSF3)2 complexes, which is particularly ensured by appropriate spatial targeting of membrane-bound ligands and their high local concentration in cell-cell interaction. In this work, (TNFSF3-TNFRSF3)2 complex formation using membrane-bound ligands was mimicked by the generation of CD40-specific antibody fusion proteins possessing additional binding domains, single chain fragment variables (scFvs), for cell-bound targets (CD70, BCMA, PDL1). For this purpose, anti-CD40 antibody heavy and/or light chains were C-terminally linked to a scFv fragment, thereby generating different CD40-specific antibody fusion proteins with scFv fragments. The functionality of these particular antibody fusion proteins was analyzed with respect to their binding ability by Gaussia princeps luciferase assay and to their agonism via detection of interleukin-8 induction by ELISA. This showed that CD40 activation could be potentiated by the scFv domains anchored to the antibody fusion proteins in a large proportion when these bind the corresponding target antigens CD70, BCMA, PDL1. Furthermore, in terms of agonimus, antibody fusion proteins with an scFv domain on the heavy or on the light antibody chain were superior to antibody fusion proteins that had scFv domains on both antibody chains. Nevertheless, the latter also represent a promising therapeutic option, as they can bind various tumor antigens due to their broader specificity. The CD40-specific antibody fusion proteins produced and characterized in this work activate the immune system in a more targeted manner in the tissue where specific tumor antigens are increasingly expressed. Thus, they open up new possibilities in tumor therapy.
330

In Vitro Studies of Tyr-MIF-1 With Human Lymphocytes

Chi, David S., Strimas, John H., Kastin, Abba J. 01 January 1989 (has links)
Our previous report showed that the brain peptide Tyr-MIF-1 (Tyr-Pro-Leu-Gly-NH2) blocks the inhibitory effect of morphine sulfate on E-rosette formation by human peripheral blood lymphocytes (PBL). In this study, additional in vitro effects of Tyr-MIF-1 on human PBL were studied. The percentages of positive cells for CD 2, a sheep erythrocyte receptor, CD 4 and CD 8 were unchanged after incubation of PBL with morphine or morphine plus Tyr-MIF-1. Tyr-MIF-1 was not mitogenic by itself. The addition of Tyr-MIF-1 did not increase the proliferative response of PBL to Con A, although morphine did. Tyr-MIF-1 did not activate PBL to produce IL 2 nor did it affect the production of IL 2 by Con A-stimulated PBL. The results suggest that Tyr-MIF-1 does not directly modulate CD 2, CD 4 and CD 8 expression, does not alter the proliferative response of PBL, and does not affect the production of IL 2.

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