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1

Influence of maleic esters on β-phase content in isotactic polypropylene

Świątek-Prokop J., Ślusarski L.

Prace Naukowe Akademii im. Jana Długosza w Częstochowie. Edukacja Techniczna i Informatyczna

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2012

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T. 7

55--62

EN

The object of investigation was isotactic polypropylene modified by following monoesters: allyl maleate [AM], butyl maleate [BM], dodecyl maleate [DM], monoallyl tetrahydrophtalate [THFA]. Some samples were crosslinked by dicumyl peroxide [DCP]. The obtained samples were characterized by: wide angle X-ray scattering (WAXS), small angle X-ray scattering (SAXS) to characterize degree of crystallinity, coefficient of β-phase contents and its dimension. WAXS investigation were carried out in the scattering angle range 4-60° with a step 0,1°. Each diffraction curve was deconvoluted into individual crystalline peaks and amorphous halo according to the procedure proposed by Hindeleh and Johnson. SAXS investigation were performed in the scattering angle 2Θ=0,09-4,05° with a step of 0.01o. It was observed, that DCP delays nucleation of β-phase. β-phase contents decreased about 50% in relation to the unmodified iPP. The addition of coagents to the iPP decreases β-phase content. The special case is BM, we didn’t observe that phase at all. Only DM promotes nucleation of β-phase, value of K coefficient, proposed by Turner - Jones, was doubled. In the case iPP/DCP and coagents, the most usefull was AM and DM. Obtained results shows, that from technological point of view, the most interesting compositions are these containing DCP, and DM or AM.

PL

Przedmiot badań był izotaktyczny polipropylen modyfikowany estrami kwasu maleinowego. Niektóre próbki były dodatkowo usieciowane za pomocą nadtlenku dikumylu. Materiał badano, wykorzystując metodę wąskokątowego i szerokokątowego rozpraszania rentgenowskiego. Do wyznaczenia zawartość fazy β w iPP wykorzystano natężenie refleksu od płaszczyzny (300), obliczając wskaźnik zaproponowany przez Turnera-Jonesa. Zaobserwowano, iż obecność DCP w materiale wpłynęła na nukleację fazy β, której zawartość wzrosła o 50% w stosunku do niemodyfikowanego iPP. Z zastosowanych estrów najskuteczniejszymi okazały się maleinian mono allilowy oraz maleinian mono dodecylowy. Uzyskane wyniki prowadzą do wniosku, że z technicznego punktu widzenia najlepszy jest układ zawierający DCP i DM.

2

Badania właściwości kompozytów wolframowych wykonanych z różnie przygotowanych miszanek. Cz. 1. Badania właściwości fizycznych mieszanek proszków

Kaczorowski M., Ludyński Z., Nowak W., Skoczylas P., Rafalski M.

Rudy i Metale Nieżelazne

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2007

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R. 52, nr 9

560-565

PL

Przedstawiono wyniki badań wpływu sposobu i parametrów mieszania proszków: W, Ni, Fe i Co na ich morfologię i strukturę, a także jednorodność mieszanek, przeznaczonych do wytworzenia wolframowych stopów ciężkich. Przeanalizowano zmiany zawartości poszczególnych pierwiastków po 2, 6, 15 i 20 godzinach mieszania w mieszalniku bębnowym. Przeprowadzono badania strukturalne oraz właściwości fizycznych proszków, w tym także rentgenowską analizę strukturalną. Stwierdzono, że mielenie energetyczne w młynku planetarnym powoduje rozdrobnienie ziaren, a także zmianę rozkładu ich wielkości w porównaniu do mieszania konwencjonalnego w mieszalniku bębnowym. Nie stwierdzono natomiast efektu tzw. stopowania mechanicznego proszków.

EN

The results from studies of an effect of a method and parameters of mixing powders of W, Ni, Fe and Co on their morphology and structure, and also homogeneity of mixtures used to fabricate tungsten-based heavy metals are presented. The changes in a content of particular elements after 2, 6, 15 and 20 hours of mixing in a drum mixer were analysed. The powders were subjected to structural examination and their physical properties were determined, also by the X-ray structural analysis. It was found that energetic milling in a planetary mill results in grain refinement and in the changes in grain size distribution compared to conventional mixing in a drum mixer. However, the occurrence of an effect of mechanical alloying of powders has not been observed.

3

The sol-gel synthesis of barium strontium titanate ceramics

Wodecka-Duś B., Lisińska-Czekaj A., Orkisz T., Adamczyk M., Osińska K., Kozielski L., Czekaj D.

Materials Science Poland

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2007

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Vol. 25, No. 3

791--799

EN

The sol-gel derived powders of the chemical composition (Ba0.6Sr0.4)TiO3 (BST) were used in the preparation of ceramic samples. Barium acetate, strontium acetate and tetra-butyl titanate were used as starting materials. The free sintering method was used for the final densification of ceramics. The ceramic samples were characterized in terms of their crystalline structure (X-ray diffraction), microstructure (scanning electron microscopy), chemical composition (energy dispersive spectroscopy), and dielectric properties.

4

Investigation of low temperature diffusion of carbon in martensite by Mössbauer spectroscopy and X-ray diffraction

Jabłońska A., Dąbrowski L., Suwalski J., Neov S.

Nukleonika

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2006

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Vol. 51, nr 2

101-104

EN

Martensite containing 0.87 wt.% carbon was studied by Mössbauer spectroscopy at temperatures, T = 10, 15, 25, 40 and 78 K and by X-ray diffraction at T = 78 K in the course of 35 days. Samples in the form of 30 mm thick foil of pure carbon martensite with enhanced tetragonality were synthesized applying non-standard technology. The measured by X-rays (c/a - 1) ratio varies within the limits 0.044-0.055 by pulsations with a period of few hours. According to Kurdimov’s model any changes in tetragonality of martensite are fully related to the passage of carbon atoms from Oc to Oa and Ob octahedral sites or vice versa. Pulsations of the central and satellite sextets were observed by Mössbauer spectroscopy. In accordance with the conventional interpretation of satellites, these pulsations result from different spatial distribution of carbon around the Fe atoms in the diffusion process. The data of (c/a - 1) pulsations were used to determine the diffusion coefficient below 78 K. The measured diffusion coefficient of carbon in a-iron below 78 K contradicts the classical approach to the observed temperature dependence. As the temperature is lowered below 78 K, the diffusion constant approaches the nearly temperature-independent value. The low temperature branch is apparently characteristic of a quantum mechanical process dominated by tunnelling in the ground state.

5

The sol-gel synthesis of bismuth titanate electroceramic thin films

Zarycka A., Lisińska-Czekaj A., Czuber J., Orkisz T., Ilczuk J., Czekaj D.

Materials Science Poland

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2005

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Vol. 23, No. 1

167--175

EN

The present study reports results of the synthesis of randomly oriented Bi4Ti3O12 (BTO) thin films by a modified hybrid sol-gel process. Bismuth nitrate and titanium(IV) butoxide were used as the starting materials. Crystalline films were deposited on silicon and stainless steel substrates by spin coating and subsequently annealed at 650 0C. The structure of the films was investigated by X-ray diffraction. The formation of a layered perovskite-like structure with orthorhombic symmetry was confirmed. Scanning electron microscopy showed that the surfaces of the films were smooth, dense, and crack free. Conservation of the chemical composition was confirmed by energy dispersive spectroscopy.

6

Piaskowiec kwarcytowy ze Słowika k/Kielc

Pitera H.

Wiadomości Naftowe i Gazownicze

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2001

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R. 4, Nr 7 (39)

9-12

PL

W pracy zastosowano badania przy użyciu mikroskopu do światła przechodzącego, analizę rentgenograficzną oraz mikroskopię scanningową. Opierając się na wynikach uzyskanych z tych badań stwierdzono, że badany materiał to piaskowiec kwarcytowy o zawartości ok. 90% kwarcu.

7

Structure of CaO-Ga/sub 2/O/sub 3/-GeO/sub 2/ glasses: X-ray and molecular dynamics simulation studies.

Padlyak B., Mudry S., Halchak V., Korolyshyn A., Rybicki J, Witkowska A.

Optica Applicata

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2000

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Vol. 30, nr 4

691-699

EN

The X-ray scattering data for CaO-Ga/sub 2/O/sub 3/-GeO/sub 2/ glasses of stoichiometric compositions similar to that of calcium-gallium-germanium garnet (Ca/sub 3/Ga/sub 2/Ge/sub 3/O/sub 12/) Ca-gallogermanate (Ca/sub 3/Ga/sub 2/Ge/sub 4/O/sub 14/) and Ca/sub 3/Ga/sub 2/O/sub 6/ crystals are presented. Experimental results show the true glass structure of the compounds under investigation. A comparative analysis of the X-ray data for glasses and their crystalline analogies has shown that the glass network consists of gallium and germanium oxygen co-ordinated octahedra and tetrahedra. The results obtained have been compared with the results of preliminary molecular dynamics (MD) calculations of the structure of CaO-Ga/sub 2/O/sub 3/-GeO/sub 2/ glasses. The pair distribution functions (PDFs) obtained from the MD simulation, show satisfactory agreement with the X-ray data The building blocks of the CaO-Ga/sub 2/O/sub 3/-GeO/sub 2/ glass network have been proposed. The structure peculiarities of the glasses and their crystalline analogies are discussed.