93 research outputs found
Influence of aging on surface properties of laser textured and chemically modified surfaces
No full textV zaključni nalogi predstavljam rezultate trimesečnega opazovanja sprememb omočitvenih lastnosti različnih lasersko teksturiranih vzorcev nerjavnega jekla AISI 316L. Spremljala sem omočljivost lasersko teksturiranih vzorcev brez nanosov ter z nanosi epoksidne smole in epoksidne smole z nanovključki FAS-TiO2 pri sobnih pogojih ter pri zmanjšanima zračnem tlaku in vlagi. Z meritvami kontaktnih kotov vodnih kapljic sem določila omočitvene lastnosti površin ter njihovo površinsko energijo. Z optično profilometrijo in vrstično elektronsko mikroskopijo sem analizirala hrapavost in morfologijo površin različno obdelanih vzorcev. Rezultati so pokazali, da lahko superhidrofobnost jekla dosežemo posredno s staranjem lasersko teksturirane površine z ustreznimi parametri ali pa neposredno z nanosi epoksidne smole z nanovključki FAS-TiO2. Zračna tlak in vlaga vplivata na spremembe omočljivosti lasersko teksturiranega jekla brez nanosov, na omočitvene lastnosti lasersko teksturiranih vzorcev z nanosi pa nimata vpliva. Pokazala sem, da je laserska obdelava učinkovita metoda za modifikacijo morfologije površin in s tem njihove omočljivosti.This work presents the results of a three-month observation of wetting properties of differently laser-textured stainless steel AISI 316L. The samples were prepared uncoated, coated with epoxy resin, and with epoxy resin composite with inlcusion of FAS-TiO2 nanoparticles. The measurements were performed on samples kept under ambient conditions, and in conditions with reduced air pressure and humidity. Static water contact angles were measured and surface energy was calculated to evaluate surface wetting properties. Optical profilometry and scanning electron microscopy were used to analyze the roughness and morphology of laser-textured steel surfaces. The results have shown that superhydrophobicity of steel can be achieved either indirectly by aging the appropriately laser-textured surface, or directly by application of the epoxy resin composite with FAS-TiO2 nanoparticles. Ambient conditions have a significant impact on changes of wettability of laser-textured steel without coatings, but they do not affect the aging of additioanlly coated surfaces. I have shown that laser processing is an effective method for modifying surface morphology and, consequently, its wettability
Palčava šiša A Century and a Half of the Čop Family from the Border Village of Plešce
No full textPrikazujući povijest obitelji Čop iz sela Plešce autor progovara o turističkoj ponudi Gorskoga kotara u razdoblju od sredine 19. stoljeća do današnjih dana. Kuća Čopovih, u narodu zvana "Palčava šiša", bila je tijekom spomenutog razdoblja istovremeno obiteljska kuća, gostionica, trgovina i sjedište društvenog života tog područja. S obzirom da su stjecanjem povoljnih povijesnih okolnosti sačuvani izvorna gradnja iz sredine i druge polovice 19. st. te dijelovi unutarnje dekoracije, pokućstvo, peći, bogata knjižnica i opširna zbirka dokumenata, predloženo je da se "Palčava šiša" proglasi kulturnim spomenikom.By representing the history of the Čop family from the village of Plešce, the author discusses the tourist offer of the region of Gorski kotar in the period from the middle of 19th century till today. The house of the Čop family, called "Palčava šiša", was during the above mentioned period a family house, a pub, a shop and center of social life of this region. Fortunately, due to historical circumstances, original building from the middle and second half of the 19th century were preserved, together with the parts of interior decorations, furniture, furnaces, rich, library and a collection of documents, and because of these reasons the house was suggested for protection as a cultural monument
Synthesis of glazes with copper on porcelain
No full textDiplomsko delo predstavi razvoj izdelka, ki ga sestavljata porcelanasta osnova in prevleka iz glazure, kombinirane z bakrom. Avtorica dokumentira proces nastajanja izdelka predelne stene ter se poglobi v načine nanašanja bakrenih učinkov na keramiko.
Raziskava se začne z zgodovinskim pregledom uporabe bakra in bakrovih spojin kot samostojnega materiala ali barvila za druge materiale.
Del raziskave je tudi razmislek o formah dvodimenzionalnih postavitev in oblikovalskih rešitev v keramičnih materialih. Tu je omenjenih tudi nekaj avtorjev, katerih dela so navdihnila razmišljanje avtorice.
Praktični del projekta sestavljajo trije obsežnejši deli. Prvi je testiranje glazur in obnašanja bakra, podprt s fotografijami. Sledi mu del o razvoju motiva in kompoziciji dela, v katerem avtorica predstavi svoje razmišljanje ob razvoju motiva skozi skice, ki so tudi kronološko razporejene. Praktični del zaključi razvoj izdelave izdelka. Tu so predstavljeni vsi postopki, potrebni za izdelavo, ter komentar nanje.This paper presents the makings of a piece of work made of porcelain base and a glaze finish with copper details. The author documents this process of making the partition installation and concentrates on research of ways for applying copper effects on ceramic surfaces.
The research begins with a historic overview of the use of copper and its compounds for independent use as well as a colourant for other materials.
A part of research also consists of consideration of different two-dimensional compositions and design solutions made with ceramic material. In this chapter there are also mentions of different authors whose work inspired authors contemplation on form.
The practical part of the project consists of three bigger(respective) parts. First there is the testing of the interaction between glaze and copper, supported by photographs. Followed by the development of this project in regard of motive and composition. Here the thought process of the author is explained through chronologically arranged sketches and minor projects. This practical part is concluded with the chapter dedicated to presenting the development and work process on the project itself
Unreliable narrator in three contemporary Slovenian novels
No full textTipologija pripovedovalca se je skozi čas močno spremenila. Nezanesljivi pripovedovalec je najnovejša kategorija, rezultat kompleksnih procesov, ki s povezovanjem bralca, avtorja in literarnega dela odpira prostor za nove interpretacije. V sodobnih slovenskih romanih Črni dnevi in beli dan (Dominik Smole), Volčje noči (Vlado Žabot) in Angeli in volkovi (Jasna Blažič) nezanesljivost pripovedovalca močno vpliva na bralčevo dojemanje zgodbe.The typology of the narrator has changed dramatically over time. The Unreliable Narrator is the latest category, the result of complex processes that, by connecting the reader, author and literary work, opens up room for new interpretations. In the contemporary Slovenian novels Črni dnevi in beli dan (Dominik Smole), Volčje noči (Vlado Žabot) in Angeli in volkovi (Jasna Blažič) the narrator’s insecurity has influenced the reader\u27s perception of the story
Pomen in vloga (slovenskih) narečij danes
No full textNarečno raznolikost slovenskega jezika lahko brez težav še danes prepoznata tako laik kot strokovnjak. Z močno spremenjenimi družbenimi in političnimi razmerami pa se spreminjata tako pomen in vloga slovenskega jezika v celoti kot pomen in vloga njegovih posameznih zvrsti. V prispevku je nanizanih nekaj avtoričinih misli o tem, zakaj narečna zvrst zadnji dve desetletji v slovenskem jezikovnem prostoru vse bolj prevzema vloge, sicer namenjene knjižnemu jeziku. Med vzroki izpostavlja 1) individualizacijo družbe ob siceršnji globalizaciji2) oddaljevanje knjižnega jezika od žive rabe z vse večjo rabo tujega, t. i. globalnega angleškega jezika, kar usmerja nosilce slovenskega jezika k iskanju novih na~inov izražanja identitete3) jezikovno modo, nastalo s sprejemom narečne zvrsti v medije.Even today, the diversity of Slovene dialects is easily recognised by both lay people and experts. Alongside greatly altered social and political conditions, both the importance and the role of the Slovene language as a whole and the meaning and role of its varieties are also changing. The article offers a number of the author’s thoughts on why dialect has in the last two decades, in areas where Slovene is spoken, increasingly taken on roles normally reserved for the standard language. The author emphasises three reasons for this: 1) the individualisation of society, alongside globalisation2) the increasing distance of the standard language from actual use, with the ever greater use of the
foreign, i.e. global English, which leads speakers of Slovene to seek new ways of expressing their identity3) linguistic “fashion” resulting from the acceptance of dialects in the media
Vraževerje in čarovništvo v šentruperskih povedkah
No full textV prispevku je obravnavan odsev verovanj in vraževerja ter čarovništva in magije v povedkah, zbranih v vzhodnodolenjski občini Šentrupert. Vsaj za posameznike je bilo do nedavna čarovništvo nekaj samo po sebi umevnega, seveda slabega, in je imelo svoj protipol v posameznikih, ki so negativne posledice znali odpraviti. Dalo se je ukaniti tudi zelo personificiranega hudiča, medtem ko se je zaščita proti mori že izgubila iz ljudskega spomina. Sproti je opozarjeno na podobnosti in razlike z ugotovitvami sicer širše raziskave vaškega čarovništva v vzhodni Sloveniji (Mencej 2006).
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This paper is a discussion of the reflections of beliefs, superstitions, witchcraft and magic in folk tales gathered in the eastern Dolenjska municipality of Šentrupert. Until recently, at least some individuals there believed in witchcraft as something self-evident and malevolent as well as in the existence of persons who knew how to eliminate its negative consequences. This included tricking the highly personified ‘devil’(hudič), while protection against ‘(night)mare’ (mora) has already disappeared from folk memory. The author also points out the similarities and differences to findings of broader research on village witchcraft in eastern Slovenia (Mencej 2006)
Parallelt. [Übers. des Autors]: Tunable surface acoustic wave resonators om multifunctional layer systems
No full textEine Vielzahl unterschiedlicher Filterkomponenten werden zur Herstellung mobiler Multiband Telefone benötigt. Zur Reduktion der Anzahl dieser Einzelfilter und damit zur Steigerung der Integration im Frontend sowie der Flexibilität des Mobilteils in Richtung eines 'software defined radios' wäre ein einzelnes abstimmbares Filter mit gleicher Funktionalität wünschenswert. Sowohl elektrische als auch akustische Lösungen zur Realisierung solcher Filter werden untersucht.Geringe Güten und hoher Platzbedarf verhindern den Einsatz abstimmbarer elektrischer Filter für den Mobilfunk. Akustische Filter hingegen weisen die benötigte hohe Güte und geringen Platzbedarf auf, aufgrund der Kristallstabilität jedoch ist ihre Mittenfrequenz fixiert. Akustische Bauteile mit geringer Abstimmbarkeit der Verzögerungszeit oder der Phase wurden zwar realisiert, die Mittenfrequenz allerdings blieb unverändert.In dieser Arbeit werden in der Frequenz abstimmbare akustische Resonatoren, die als elementare Bausteine für Filter benutzt werden können, sowohl theoretisch als auch experimentell untersucht. Die Abstimmbarkeit in der Frequenz wird durch ein Substratmaterial realisiert, dessen Steifigkeit sich durch ein angelegtes Magnetfeld ändert ([Delta]E-Effekt). Die Anregung der Oberflächenwelle selbst wird mit einer piezoelektrischen ZnO-Schicht erreicht. Für amorphe magnetostriktive Materialien wie FeCoSiB sind Steifigkeitsänderungen von mehr als 100 % publiziert. Somit sind theoretisch Frequenzverschiebungen von bis zu 30 % realisierbar. Die Eigenschaften von Oberflächenwellen in diesem Schichtsystem wurden mit Hilfe des kommerziellen FEM-Code ANSYS simuliert. Untersucht wurde die optimale Schichtkonfiguration in Bezug auf die piezoelektrische Kopplung und die maximale Abstimmbarkeit. Zur Herstellung von Proben wurden zwei Aufbauvarianten, ein direktes Schicht auf Schicht sowie ein neu entwickeltes Opferschichtverfahren, verwendet. Das direkte Verfahren verursacht eine Rekristallisation der amorphen FeCoSiB-Schicht und daher eine Reduktion des [Delta]E-Effektes und der erreichbaren Frequenzverschiebung. Mit dem Opferschichtverfahren wird diese Rekristallisation verhindert, eine bessere c-Achsen Orientierung der ZnO-Schicht und damit eine Steigerung der piezoelektrischen Kopplung erreicht. Mit einer Abstimmbarkeit von 1.2 % bei einer Mittenfrequenz von 1.2 GHz des Resonators übertrifft der hier gemessene Wert bisher erreichte um einen Faktor 100. Eine weitere Steigerung ist durch die Optimierung der magnetischen Schicht möglich. Die bei der Frequenzabstimmung gleichzeitig auftretende Dämpfung der OFW limitiert jedoch die maximal erreichbare Abstimmbarkeit. Die Dämpfung kann durch die Substitution der magnetostriktiven Schicht durch ein Schichtsystem aus magnetostriktiven und isolierenden Schichten mit kleiner effektiver magnetischer Permeabilität bei der Anregungsfrequenz der OFW reduziert werden. Dieser Aufbau wird zur Realisierung von Bauteilen mit großer Abstimmbarkeit und geringen Verlusten vom Autor vorgeschlagen.Up to now cellular multiband phones require a multitude of different filter components. For higher integration, a reduction of the number of components in the front end and an increase of flexibility and functionality of the wireless terminals, towards software radio applications, one single tunable filter would be highly desirable.Different approaches to realize tunable filters include electrical filters on the one hand and acoustical solutions on the other hand. Due to the low achieved quality factors and the large size of tunable electrical filters this technique fails for mobile phone applications.On the other hand acoustical filters combining high quality factors with low size exhibit a fixed center frequency due to crystal stability.However, tunable acoustic device with small tuning ranges were realized, but only the delay time or phase dependency was altered while the center frequency remained unchanged. This works describes the synthesis of a frequency tunable acoustic resonator as a basic filter element. A new approach is used to directly change the propagation velocity and thus the center frequency of a surface acoustic wave (SAW) underneath the interdigital transducer. This is achieved by using a smart layer structure combining a piezoelectric layer for the SAW excitation and a magnetostrictive layer exhibiting the [Delta]E-effect. By an external magnetic field the elastic stiffness is varied and hence the propagation velocity. Amorphous magnetostrictive materials like FeCoSiB show stiffness changes up to 100 %. Therefore a frequency shift of about 30 % should be feasible, theoretically. To simulate the SAW propagation behavior in such a layer structure the standard FEM code ANSYS was applied. The optimum layer configuration concerning the piezoelectric coupling coefficient and the attainable tunability of the device was investigated for two different fabrication techniques. Both a layer by layer deposition and a sacrificial layer technique were used to realize samples. By applying the conventional layer by layer deposition a crystallization of the previously amorphous FeCoSiB layer occurs. The increase in crystallinity causes a decrease in the magnitude of [Delta]E-effect and thus a reduction of the achievable tuning effect. This is avoided using the sacrificial layer technique, which additionally leads to a higher c-axis orientation of the ZnO and thus an increase in piezoelectric coupling coefficient. The measured maximum tuning range was 1.2 % at a center frequency of 1.2 GHz, which is by a factor 100 more than has been achieved so far for SAW devices, but may still be enhanced by optimizing the magnetostrictive layer. A direct correlation between the tuning of center frequency and SAW attenuation was observed, which limits the frequency tuning to small ranges with the applied material system. By substituting the single magnetostrictive layer by a multi layered system, combining magnetostrictive and isolating layers with low or vanishing magnetic permeability, regardless in the frequency range of operation of the SAW device damping effects may be overcome. Such a setup is suggested by the author to realize a device combining high tuning range with low loss effects.<br /
De haven van Monrovia, golfklimaat toegangsgeul
No full textDit rapport is een vervolgstudie op het door Smole en van de Vijver [1] verrichtte vooronderzoek betreffende de aanpassing van de haven van Monrovia. De aanpassing van de haven moet het mogelijk maken schepen van 150.000 dwt te ontvangen. De huidige haven lay-out staat de ontvangst van ertscarriers van 80.000 dwt toe. In het kader van deze aanpassing zijn in dit rapport de volgende aspecten nader onderzocht: - De binnenloopmanoeuvre van het maatgevende schip. - Geuldiepte en geulorientatie. - Aanzanding van de toegangsgeul In het deelrapport is de lange termijn statistiek van het golfklimaat in de toegangsgeul van de haven van Monrovia bepaald. Deze golfklimaatbeschrijving is uitgevoerd in het kader van de in het hoofdontwerp " De haven van Monrovia " te verrichten geuldieptebepaling. De verticale scheepsbeweging onder invloed van golven is bij deze bepaling van bijzonder belang. De grootte van deze scheepsbeweging is met name afhankelijk van de combinatie hoek van inval van de golven op het schip en de bijbehorende gemiddelde golfperiode. Bij de bepaling van de verticale scheepsbeweging is het dan ook wenselijk om over golfgegevens te beschikken waarvan de informatie betreffende golfhoogte, golfperiode en golfrichting gecombineerd is.Hydraulic EngineeringCivil Engineering and Geoscience
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