Darbo tikslas yra susintetinti natrio-vanadžio oksidinę bronzą Na0.33V2O5 zolių-gelių sintezės būdu bei nustatyti jos cheminį sąstatą Rentgeno fotoelektronų spektroskopijos metodu. Darbe aprašyti zolių-gelių technologijos pagrindai, vanadžio pentoksido ir jo hidratuotų junginių struktūra, vanadžio oksidinių bronzų savybės ir sintezės būdai bei Rentgeno fotoelektronų spektroskopijos metodo pagrindai. Pateiktas išsamus vanadžio – natrio oksidinės bronzos sintezės zolių-gelių metodu technologijos aprašymas. Aprašyti eksperimentiniai bronzos ir vanadžio – natrio kserogelio Rentgeno fotoelektronų spektrai. Gautas rezultatas: nustatyta, kad zolių – gelių technologija leidžia paprastais metodais, nenaudojant sudėtingos aparatūros, susintetinti norimos cheminės sudėties vanadžio – natrio oksidines bronzas; Rentgeno fotoelektronų spektroskopijos metodas įgalina atlikti bronzų kokybinę bei kiekybinę cheminę analizę ir nustatyti metalų jonų valentines būsenas bronzoje; sintetinant bronzą iš V2O5 ir Na2SO4 galutiniame produkte nėra sieros pėdsakų; susintetintoje bronzoje vanadžio jonai yra dviejose valentinėse būsenose – V4+ ir V5+. / The main aim of the present work was the synthesis of vanadium – sodium oxide bronze by using sol-gel technology and the study of the bronze chemical composition by X-Ray photoelectron spectroscopy. The bases of sol-gel technology, the structure of vanadium pentoxide and its hydrated compounds, the properties and the structure of vanadium oxide bronzes and the bases of X-Ray photoelectron spectroscopy are described in the work. The detailed description of technological process of vanadium – sodium oxide bronze synthesis by sol-gel technology is resulted. The experimental results of the study of X-Ray photoelectron spectra of vanadium - sodium bronze ant its hydrate are described and discussed. As a result of work, it is established that sol-gel technology allows a synthesis of bronzes of necessary structure by simple methods, without using difficult equipment; X-Ray photoelectron spectroscopy method allows making a quantitative and qualitative analysis of the composition of the bronzes and an establishment of the valence of metals ions; when the bronze was synthesized V2O5 and Na2SO4, the sulphur presence was not observed in the bronze; vanadium ions in the bronze are in V4+ and V5+ states.

The hyperfine structure of the ground state of vanadium, is calculated in the nonrelativistic framework of the multi-configiuration Hartree-Fock approximation. A configuration state function limiting algorithm is used to make the calculations feasible and to study the influence of core, valence and core-valence correlations in detail.

Zolis-gelis procesas, kuris turi potencialiai didelę technologinę vertę, leidžia sukurti medžiagas, kurių unikalios struktūros ir savybės yra retai gaunamos naudojant kitus metodus. Šio darbo užduotis- pagaminti Vanadžio-Titano-hidrochinono oksidinę bronzą panaudojant zolis-gelis technologiją bei ištirti vanadžio ir titano jonų valentingumą juose naudojant Rentgeno fotoelektronų spektroskopijos metodą. Darbe aprašoma Zolio-Gelio technologijos pagrindai, Rentgeno fotoelektronų spektroskopija ir jos spinduliuotės prietaisai, bei matavimo metodika. Aprašyti eksperimentiniai bronzos ir vanadžio – titano- hidrochinono kserogelio Rentgeno Fotoelektronų spektrai. Darbe pateikti ir lyginami grafikai buvo braižomi paisnaudojus įvairiomis programomis (SDP, XPS ir Origin). Apibendrinant šio darbo rezultatus, galima teigti, jog Vanadžio- Titano- hidrohinono kserogelyje vanadis yra V5+, V4+ ir V3+ būsenose, o deguonies jonai surišti su vanadžiu, hidroksilinėmis grupėmis ir molekuliniu vandeniu. Vanadžio- Titano- hidrochinono kserogelio kaitinimas aplinkos atmosferoje iki 580K leidžia visiškai pašalinti iš kserogelio chemiškai surišta vandenį, tai yra pereiti nuo kserogelio prie bronzos. / Sol-gel process, which has a potentially high technological value, allows you to create materials with unique structure and properties are reraly generated using other methods. This work made the task – Vanadium-Titanium-hydroquinone oxidic bronze using the sol-gel technology and study of vanadium and titanium ion valence them using X- ray photoelectron spectroscopy. The paper describes the sol-gel technology basics, X-ray photoelectron spectroscopy radiation devices, and measurement techniques. Describe the experimental and vanadium - titanium - hydroquinone xerogels and bronze X-ray photoelectron spectra. The paper presents and compares graphs were drawn from this various programs (SDP, XPS and Original). Summing up the results, one can argue that the vanadium-titanium in xerogel is V5+, V4+ and V3+ states and the oxygen ions are bound to vanadium hydroxyl groups and molecular water. Vanadium- titanium-hydroquinone xerogels heating in the atmosphere to 580K allows to completely remove from the xerogels chemically bound water which is the transition from xerogels to bronze. Vanadium and titanium ions in the bronze are in stable V5+ and Ti4+ states respectively.

Une trace est une suite d’empreintes, laissées par le passage d’un être ou d’un objet – c’est donc avant tout l’indice d’un chemin parcouru. C’est à ce déplacement dans le temps et dans l’espace qu’invitent mes travaux de recherche dont l’objectif est de suivre Edith Wharton « à la trace ». La trace, c’est d’abord, pour ce qu’elle nous apprend sur le voyageur et son rapport au monde, cette croisière en Méditerranée qu’elle entreprend en 1888 à bord du Vanadis. C’est également l’empreinte qui subsiste de cette expérience du voyage : un manuscrit dactylographié qui retrace le périple et rend compte du rapport particulier d’Edith Wharton à l’écriture.La trace – ce qu’on suit (« suivre à la trace ») – renvoie donc à une double activité : d’une part au voyage lui-même, d’autre part, à l’exploration de toutes les pistes que j’ai cru bon d’ouvrir à partir du document originel : sur la vie et l’œuvre d’Edith Wharton, sur son environnement socio-culturel et sur le genre de la littérature de voyage – toute une série d’empreintes, donc de signes conduisant à de nombreux signifiés. La question demeure toujours, en dernier ressort, de savoir si les signifiés que croit avoir découvert le chercheur sont bien ceux de l’écrivain. / A trace is both a material imprint and a trail or series of imprints, marking the passage of a being or an object in transit; it can therefore be understood as the material evidence of a path that has been pursued. In the particular context of this research, the term trace refers first and foremost to the record of a sea voyage. This unpublished journal, kept by Edith Wharton, gives an account of the various stages of the Mediterranean cruise she made in the yacht, the Vanadis, in the spring of 1888.This long book is of particular interest, insofar as it, not only gives a fascinating account of the response of a young nineteenth-century cultivated American to the different cultures discovered in the course of a voyage leading her from North Africa to the Greek Islands and the shores of the Adriatic, but also provides valuable insight into the early responses of an artist in the making.The term “trace” therefore refers to both these aspects: first the voyage itself, the places visited, their physical features and historical significance; secondly the traces left by the visitor who embarked on this adventure at a turning point in her life. The sentiment that the future artist is poised at the crossroads of her existence, leads the researcher – in an attempt to leave as few stones as possible unturned – on a trail leading back to her past and forward to her future. This investigation would not be complete without a survey of travel literature, as the particular genre Edith Wharton has chosen as her means of expression. All these traces unite to form a series of “signs” (in the Saussurian sense of the word), which the researcher endeavours to interpret in the hopes of understanding what is “signified” on a deeper level.

Šiame darbe panaudojant zolis-gelis technologiją, susintetinti vanadžio junginių oksidinio kserogelio ir bronzos bei molekulinio oksidinio kserogelio ir bronzos plonieji sluoksniai. Visų minėtų medžiagų cheminė sudėtis ištirta Rentgeno fotoelektronų spektroskopijos metodu, siekiant nustatyti metalų jonų valentines būsenas. Panaudojant zolis-gelis technologiją, galima gana paprastais metodais, nenaudojant sudėtingos technologinės įrangos, gaminti vanadžio oksidinių bronzų plonuosius sluoksnius. Vanadžio amonio hidratuoti oksidiniai junginiai gali būti naudojami kaip medžiagos amoniako dujų jutikliams gaminti. / The thin films of molecular oxide xerogels and bronzes as well as oxide xerogels and bronzes of vanadium compounds were synthesized by sol-gel technology method. The chemical composition of mentioned compounds was investigated using XPS method in order to determine the valence of metal ions. It is shown that it is possible to produce the thin films of vanadium oxide bronzes using simple methods. The possibility to use vanadium-ammonium oxide hydrated compounds as materials for producing the ammonium sensors is shown in the dissertation.

The thin films of oxide xerogels and bronzes and molecular oxide xerogels and bronzes of vanadium compounds were synthesized by sol-gel technology method. The chemical composition of mentioned compounds was investigated using XPS method in order to determine the valence of metal ions. It is shown that it is possible to produce the thin films of vanadium oxide bronzes using simple methods. The possibility to use vanadium-ammonium oxide hydrated compounds as materials for producing the ammonium sensors is shown in the dissertation. / Šiame darbe panaudojant zolis-gelis technologiją, susintetinti vanadžio junginių oksidinių kserogelių ir bronzos bei molekulinių oksidinių kserogelių ir bronzų plonieji sluoksniai. Visų minėtų medžiagų cheminė sudėtis ištirta Rentgeno fotoelektronų spektroskopijos metodu, siekiant nustatyti metalų jonų valentines būsenas. Panaudojant zolis-gelis technologiją, galima gana paprastais metodais, nenaudojant sudėtingos technologinės įrangos, gaminti vanadžio oksidinių bronzų plonuosius sluoksnius. Vanadžio amonio hidratuoti oksidiniai junginiai gali būti naudojami kaip medžiagos amoniako dujų jutikliams gaminti.

This work deals with tool steel Vanadis 6. It describes the preparation of samples for the three-point bending test, with which it examines the influence of surface roughness, the effect of nitriding, coating and duplex coatings on fracture behaviour of the steel. First, it examines bending strength and the total energy required to work of fracture. The work also includes mapping and measurement of surface roughness on different layers. This measurement is performed on a confocal microscope.

Additive manufacturing (AM) has experienced significant growth and development in recent years, owing to the ability to produce complex parts using a wide range of materials with relative ease. Powder bed-based metal AM has been at the forefront of this growth, even reaching the point where parts can be manufactured for end-use applications. Binder jetting (BJ) is one such technique where a liquid binder is selectively deposited on powder layers to create a green body which is then densified using sintering. The aim of this work was to use binder jetting to produce parts using Vanadis 4 Extra, a highly alloyed cold-work tool steel produced by Uddeholm AB for applications involving high demand on abrasive wear. Optimization of the densification parameters, which included debinding atmosphere, debinding temperature, sintering atmosphere, sintering temperature, and sintering time, to achieve full density parts was carried out as the first phase. It was found that the sintering atmosphere and time had the most significant impact on the density of the samples while the debinding atmosphere heavily impacted the C residue from the binder. In the second phase, samples were produced using the optimized parameters for mechanical analysis, which included analyses of the surface roughness and the wear resistance of the binder jetted samples against the conventionally produced samples. The surface roughness was in line with the data presented in literature for binder jetted samples. The binder jetted samples produced during this work exhibited better wear resistance than the conventionally produced samples, with the samples post-processed using hot isostatic pressing showing even better wear resistance. One possible explanation is the diffusion of N from the sintering atmosphere into the samples, leading to the conversion of carbides to carbonitrides and even nitrides. However, further investigation is needed in order to confirm this theory.