| | SLO | ENG | Piškotki in zasebnost

Večja pisava | Manjša pisava

Iskanje po katalogu digitalne knjižnice Pomoč

Iskalni niz: išči po
išči po
išči po
išči po
* po starem in bolonjskem študiju


1 - 10 / 10
Na začetekNa prejšnjo stran1Na naslednjo stranNa konec
Nanochemistry and Materials : a Laboratory Manual
Janja Stergar, Irena Ban, 2022, delovni zvezek za višje in visoke šole

Opis: The publication contains instructions for laboratory work in the subject Nanochemistry and Materials. Students are introduced to the experimental principles of nanochemistry in the laboratory. They learn about various synthesis and characterization methods, in conjunction with magnetic nanoparticles useful in biomedical and engineering applications. They learn about the safety of nanoparticles and their effects, impact on technology, and contribution to improving life on many levels when used properly. The instructions are written in English as they are intended for foreign students who choose the mentioned subject.
Ključne besede: magnetic nanoparticles, coprecipitation, microemulsion technique, X-Ray powder diffraction, dynamic light scattering
Objavljeno v DKUM: 29.08.2022; Ogledov: 448; Prenosov: 55
.pdf Celotno besedilo (3,54 MB)
Gradivo ima več datotek! Več...

Ammoniumbis(hydroxylammonium) pentafluoridooxidovanadate(IV) : synthesis and characterisation of a new fluorovanadate
Brina Dojer, Matjaž Kristl, Zvonko Jagličić, Mihael Drofenik, Anton Meden, 2008, izvirni znanstveni članek

Opis: Turquoise crystals of a new hydroxylammonium compound with the formula $NH_4(NH_3OH)_2[VOF_5]$ have been synthesized by the reaction of solid $NH_3OHF$ and the aqueous solution of vanadium in HF. The compound crystallizes monoclinic, $P2_1/n$, with cell parameters: a = 10.5658(2) Å, b = 6.6143(1) Å, c = 11.6618(2) Å, β = 96.282(1). Magnetic susceptibility was measured using a SQUID device over a temperature range 2–300 K at magnetic field $10^3 Oe$ giving the result $µ_{eff}$ = 1.65 BM. The thermal decomposition was studied by TG and DSC analysis. $NH_4(NH_3OH)_2[OF_5V]$ decomposes above 354 K in three steps, obtaining $NH_4VOF_3$ after the first step and $V_2O_5$ as the final residue.
Ključne besede: hydroxylammonium fluorovanadates, x-ray powder diffraction, x-ray structure determination, thermal analysis
Objavljeno v DKUM: 17.08.2017; Ogledov: 1602; Prenosov: 105
.pdf Celotno besedilo (218,95 KB)
Gradivo ima več datotek! Več...

Material parameters for a numerical simulation of a compaction process for sintered double-height gears
Tomaž Verlak, Marko Šori, Srečko Glodež, 2015, strokovni članek

Opis: This paper presents the initial material parameters for the Ecka Alumix 231 aluminum-powdered metal required for a successful numerical simulation of a compaction process for sintered components with a proper software package. Experimental work was used to obtain Drucker-Prager-cap (DPC) model material parameters with the help of a Brazilian disc test and a uniaxial compression test for the linear part of the DPC model in the equivalent pressure stress/deviatoric stress (p-q) plane. The specimens used for this test were cylindrical probes (greens) that were compacted with a mechanical press and then compressed to the failure point in the axial and radial directions.
Ključne besede: aluminum-based powder, compaction process, Drucker-Prager cap model, numerical simulation, Ecka Alumix 231
Objavljeno v DKUM: 16.03.2017; Ogledov: 1424; Prenosov: 411
.pdf Celotno besedilo (864,37 KB)
Gradivo ima več datotek! Več...

Fatigue properties of sintered DIN SINT-D30 powder metal before and after heat treatment
Marko Šori, Borivoj Šuštaršič, Srečko Glodež, 2014, izvirni znanstveni članek

Opis: The main focus of this study was to determine how heat treatment affects the dynamic properties of sintered steel. All the specimens were made of the DIN SINT-D30 metal powder, but only half of them were additionally heat treated. Flat specimens were cold pressed and sintered. The second set was additionally heat treated to increase the strength. After the static mechanical properties were determined, the fatigue strength was investigated in a pulsating machine with a load ratio of R = 0. Wöhler curves were plotted and the parameters for determining the fatigue life (of' and b) were calculated.
Ključne besede: powder metallurgy, fatigue, S-N curve
Objavljeno v DKUM: 16.03.2017; Ogledov: 1223; Prenosov: 115
.pdf Celotno besedilo (157,94 KB)
Gradivo ima več datotek! Več...

Water sorption characteristics of a new type of gelatine powder, produced by a new high-pressure micronisation process
Christian Reibe, Željko Knez, 2010, izvirni znanstveni članek

Opis: A new high-pressure micronisation process for Gelatine has been developed. By applying this process to gelatine, a new type of Gelatine was produced: Dry and pure Gelatine powder of high molecular mass. This powder was investigated,regarding its sorption behaviour and compared to its feedstock material. The feedstock Gelatine was of type B 200 Bloom, 6 mesh, having a molecular mass of 150,000 g $mol^{-1}$. The produced Gelatine powder's molecular mass was around 130,000 g $mol^{-1}$, while its mean particle size was 300 μm. Their sorption isotherms were investigated at 30 °C, 40 °C and 60 °C and water activities in the range from 0.055 to 0.836. At given water activities the Equilibrium Moisture Contents (EMC) decreases with increasing temperature.The measured sorption isotherms were fit with the Brunauer- Emmet-Teller (BET)- model and the Guggenheim- Anderson- deBoer (GAB)- model. Both models described the adsorption behaviour well in their range of validity, while only the GAB-model was adequate for describing the desorption behaviour. Hysteresis effect occurred in each adsorption-desorption pair. The isosteric heat of sorption of both substances was determined for adsorption, desorption respectively. Slight differences in the sorption behaviour occurred due to processing, while quality of the gelatine was not affected.
Ključne besede: $CO_2$ spray drying, gelatine powder, sorption isotherms, isosteric heat of sorption, Guggenheim-Anderson-deBoer model, Brunauer-Emmet-Teller model
Objavljeno v DKUM: 10.07.2015; Ogledov: 1670; Prenosov: 65
.pdf Celotno besedilo (317,43 KB)
Gradivo ima več datotek! Več...

Dynamic property of aluminium foam
Seiichi Irie, Toshihiko Okano, Shigeru Tanaka, Matej Vesenjak, Zoran Ren, Kazuyuki Hokamoto, Shigeru Itoh, 2010, objavljeni povzetek znanstvenega prispevka na konferenci

Ključne besede: aluminium foam, powder gun, high strain rate
Objavljeno v DKUM: 10.07.2015; Ogledov: 1543; Prenosov: 46
URL Povezava na celotno besedilo

Particles formation and particle design using supercritical fluids
Željko Knez, Eckhard Weidner, 2003, pregledni znanstveni članek

Opis: Major recent advances. Particle formation and design of solid particles and powdery composites with unique properties is at the moment a major developmentof supercritical fluids (synonymsČ dense gasses, dense fluids, highpressure) applications. This review will focus on recent advances and on fundamentals of these processes and their applications.
Ključne besede: chemical processing, high pressure technology, micronization, supercritical fluids, micro-particles, nano-particles, powder generation, crystallization, particles from gas saturated solutions
Objavljeno v DKUM: 01.06.2012; Ogledov: 3590; Prenosov: 107
URL Povezava na celotno besedilo

Multifunctional composites by high-pressure spray processes
Eckhard Weidner, Marcus Petermann, Željko Knez, 2003, pregledni znanstveni članek

Opis: A series of spraying processes designed to generate powders and composites using supercritical fluids have been proposed in the past 15 years. In this review, thermo- and fluid-dynamic aspects and engineering principles are discussed and advantages of such technologies are demonstrated. These new techniques display convincing advantages, producing competitive high-quality products with tailor-made properties. Initial industrial applications have been achieved in the production of food products and fine-chemicals.
Ključne besede: chemical processing, high pressure technology, micronization, supercritical fluids, particles, powder generation, thermodynamics, fluid dynamics, PGSS
Objavljeno v DKUM: 01.06.2012; Ogledov: 2424; Prenosov: 102
URL Povezava na celotno besedilo

Hydroxylammonium fluorogermanates
Irena Ban, Matjaž Kristl, Mihael Drofenik, Arkadije Popović, 2004, izvirni znanstveni članek

Opis: A new hydroxylammonium compound (NH3OH)2GeF6, has been synthesized by the addition of solid NH3OHF to a solution of GeO2 dissolved in 20% HF. The compound was characterized by chemical analysis and X-ray powder diffraction, the thermal decomposition was studied by thermal analysis and mass spectrometry. (NH3OH)2GeF6 crystallizes monoclinic. Two endothermic and two exothermic peaks have been observed on the DSC curve, the decomposition product at 500 °C is GeO2.
Ključne besede: inorganic chemistry, synthesis, characterisation, hydroxylammonium fluorogermanates, x-ray powder diffraction, mass spectroscopy, thermal analysis
Objavljeno v DKUM: 01.06.2012; Ogledov: 2864; Prenosov: 109
URL Povezava na celotno besedilo

The development of a new process for gentle drying, micronisation and formulation of a high viscous biopoymer
Christian Reibe, 2011, doktorska disertacija

Opis: Biopolymers are characterised by their biodegradable behaviour in certain environments. Especially the development of natural biopolymers from renewable resources is gathering increasing interest in the scientific as well as in the industrial sectors . Since Biopolymers may be tailored to specific requirements, the encapsulation of pharmaceutical compounds or flavours in biopolymers would open wide avenues for the production of controlled- release systems. Most common mechanical pulverisation processes are milling and grinding. With these processes it is not possible to produce specific morphologies like foams or hollow spheres, but always splintered edges. Encapsulation is carried out by common precipitation techniques. Gelatine, as a widely applied biopolymer, represents one example of those substances of large interest, but it is difficult to process. Especially gelatines with high molecular mass are difficult or almost impossible to be pulverized by spray drying techniques, due to their high viscosity. In the frame of this research work, an integrated high-pressure spraying, drying and pulverization process for high viscous gelatine was developed, based on a combination of the water removing effects "Evaporation" and "Gas-solubility". The resulting products were dry, free-flowing gelatine powders, still exhibiting high molecular masses. Due to the new, gentle method of processing, a completely new gelatine product with unique properties was obtained. Even the encapsulation of edible oil in high ratios was found to be possible with this new process. The characterisation was carried out by standard methods for gelatine on the one hand side, and standard procedures for characterising powders on the other hand side. The developed process was patented under the identifier "WO 002009135601 A1".
Ključne besede: High Pressure Process, Supercritical Fluids, High molecular mass Gelatine, Micronisation, CO-2 - spray drying, Encapsulation, Gelatine Powder
Objavljeno v DKUM: 26.01.2011; Ogledov: 3358; Prenosov: 219
.pdf Celotno besedilo (24,89 MB)

Iskanje izvedeno v 0.23 sek.
Na vrh
Logotipi partnerjev Univerza v Mariboru Univerza v Ljubljani Univerza na Primorskem Univerza v Novi Gorici