Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "microspheres" wg kryterium: Temat


Tytuł:
Mechanical properties of porous collagen/ gelatin/ hydroxyethyl cellulose matrices containing microspheres based on sodium alginate
Autorzy:
Kozlowska, J.
Tybinkowska, O.
Sionkowska, A.
Powiązania:
https://bibliotekanauki.pl/articles/284591.pdf
Data publikacji:
2018
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Polskie Towarzystwo Biominerałów
Tematy:
polymeric materials
microspheres
cellulose
Źródło:
Engineering of Biomaterials; 2018, 21, 148; 84
1429-7248
Pojawia się w:
Engineering of Biomaterials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Preparation of NC Microspheres and BuNENA Modified NC Microspheres by the Breath Figures Method
Autorzy:
He, L.
He, W.
Luo, Y.
Powiązania:
https://bibliotekanauki.pl/articles/358176.pdf
Data publikacji:
2016
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
breath figures method
thermal decomposition
NC microspheres
BuNENA modified NC microspheres
Opis:
The ‘breath figures’ method was used to prepare nitrocellulose (NC) microspheres and N-butyl-N-(2-nitroxyethyl)nitramine (BuNENA) modified NC microspheres (BMNM). By using acetone as the solvent and non-solvent n-hexane as the atmosphere, NC microspheres and BMNM were obtained. The matching of solvents and non-solvents was the key factor influencing the final morphology. TG and DSC were employed to study the thermal decomposition characteristics of BMNM. The results suggested that there were two distinct stages of thermal mass loss from the BMNM: the first was the mass loss associated with partial volatilisation of BuNENA, and its activation energy was 68.54 kJ/mol. The second mass loss was the thermal decomposition of NC and residual BuNENA with a high activation energy (249.53 kJ/mol, calculated by the Kissinger method). According to the thermal decomposition kinetics model, the optimal kinetics model of BMNM was B1-A2. The addition of BuNENA did not influence the thermal decomposition of NC.
Źródło:
Central European Journal of Energetic Materials; 2016, 13, 3; 567-578
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Estimation and measurements of resonance scattering on the gas filled polymer microspheres
Autorzy:
Secomski, W.
Klimonda, Z.
Powiązania:
https://bibliotekanauki.pl/articles/332832.pdf
Data publikacji:
2009
Wydawca:
Polskie Towarzystwo Akustyczne
Tematy:
polymer microspheres
gas filled
hydroacoustics
Opis:
The gas filled polymer spheres are used either as an ultrasonic contrast agents or controlled drug delivery microcapsules. The power spectrum of the ultrasonic backscattered signal was calculated from the resonance scattering theory for the gas bubbles surrounded by elastic shield. The size distribution of the measured microspheres was included in the calculations. In experiment, the backscattered power spectrum of measured sample was recorded by Siemens Antares ultrasonic scanner. Radio frequency (RF) data was recorded for 2.5 - 6.7 MHz transmitted ultrasonic frequencies. The backscattered spectra were calculated by Matlab software and subtracted from the transmitter spectrum, recorded as an echo from the perfect reflector. The particle size in measured sample was 12 µm mean š 8 µm sd. The resonance frequency, measured under the microscope, was 0.60 MHz for 45 µm diameter microsphere which corresponds to 2.25 MHz for 12 µm sphere. The sample volume was 10cm? and the mean quantity of scatterers was 6ź103/cm?. In conclusion, measured spectra matched those calculated from theory. The use of ultrasonic scanner with RF data output and the high sensitivity, wide bandwidth ultrasonic transducer allows to measure backscattered signal from the very small quantity of resonance scatterers with satisfactory results at 40 dB signal to noise ratio.
Źródło:
Hydroacoustics; 2009, 12; 201-208
1642-1817
Pojawia się w:
Hydroacoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mikrosfery : pozyskiwanie, właściwości, zastosowania
Microspheres : acquisition, properties, applications
Autorzy:
Wajda, A.
Kozioł, M.
Powiązania:
https://bibliotekanauki.pl/articles/109272.pdf
Data publikacji:
2015
Wydawca:
AXIS MEDIA
Tematy:
mikrosfery
cenosfery
mikrosfery glinokrzemianowe
pozyskiwanie
właściwości
zastosowanie
microspheres
cenosphere
aluminosilicate microspheres
acquisition
properties
application
Opis:
Mikrosfery (określane również jako cenosfery lub mikrosfery glinokrzemianowe) stanowią coraz szerzej pozyskiwany i stosowany surowiec. W artykule przedstawiono warunki powstawania oraz metody pozyskiwania mikrosfer. Podjęto się również próby oszacowania masy mikrosfer powstających rocznie na świecie. W dalszej części artykułu przedstawiono ich właściwości oraz szeroko omówiono możliwości praktycznego ich wykorzystania.
Microspheres (called also cenospheres or aluminosilicate microspheres) constitute raw material acquired and used on a wider and wider scale. The paper briefly presents conditions for formation and methods of acquisition of microspheres. Estimation of the mass of microspheres annually formed worldwide is also attempted. The following part of the paper presents properties and broadly discusses the possibilities of their practical application.
Źródło:
Piece Przemysłowe & Kotły; 2015, 1; 15-18
2082-9833
Pojawia się w:
Piece Przemysłowe & Kotły
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Preparation of micro and nanostructures of chitosan by ultrasonic coalescence of w/o emulsions
Autorzy:
Balcerzak, Jacek
Kucharska, Magdalena
Gruchała, Bogdan
Powiązania:
https://bibliotekanauki.pl/articles/1035322.pdf
Data publikacji:
2013
Wydawca:
Sieć Badawcza Łukasiewicz - Polskie Towarzystwo Chitynowe
Tematy:
chitosan
microspheres
nanospheres
precipitation
ultrasonic emulsification
Opis:
In the paper, the preeliminary study of chitosan micro and nanospheres precipitation due to two reverse emulsions (W/O) coalescence is described. The composition conditions, which must be filled to obtain stable reverse emulsion is pointed out. Furthermore, the parameters of ultrasonic emulsification and coalescence technique are presented and finally, morphological study of obtained micro and nanospheres are discussed.
Źródło:
Progress on Chemistry and Application of Chitin and its Derivatives; 2013, 18, 18; 13-20
1896-5644
Pojawia się w:
Progress on Chemistry and Application of Chitin and its Derivatives
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Badania i możliwości zastosowań mikrosfer z popiołów lotnych
The research results and application possibilities of fly ash microspheres
Autorzy:
Łach, M.
Mikuła, J.
Powiązania:
https://bibliotekanauki.pl/articles/134734.pdf
Data publikacji:
2016
Wydawca:
ADVSEO
Tematy:
fly ashes
microspheres
insulation materials
alkali activation
Opis:
The paper presents a short description of aluminosilicate materials which are microspheres derived from fly ash from coal combustion in power stations. The most important properties of such materials, the conditions of their formation, methods of obtaining and selected areas of application are discussed. The microspheres that were tested came from the Power Plant Skawina. Analysis of particle size and wall thickness of the microspheres and the analysis of the chemical composition have been carried out. This article also presents preliminary results of the alkaline activation of the microspheres in order to obtain a fraction within the zeolite. Alkali activation was carried out in several variants, using aqueous solutions of sodium hydroxide and the obtained results allow to determine the suitability of the microspheres to obtain zeolites in their substrate. Observations with the scanning electron microscope showed the existence of significant quantities of specific forms of zeolites, after alkaline activation processes of microspheres.
Źródło:
Technical Issues; 2016, 3; 74-78
2392-3954
Pojawia się w:
Technical Issues
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Expanded perlite, expanded vermiculite and microspheres as fillers in new generation paper pulp mixtures used for contact with liquid metal
Autorzy:
Zawieja, Z.
Sawicki, J.
Powiązania:
https://bibliotekanauki.pl/articles/101866.pdf
Data publikacji:
2015
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
expanded perlite
expanded vermiculite
microspheres
paper pulp
Opis:
Liquid metal when filling sand casting mould while pouring it out from ladle at the first moment comes across the sprue/gate system of the mould the purpose of which is to transfer liquid metal and feed the mould recess. The materials presently used for the elements of the sprue/gate systems are based on ceramics or the mixtures based on paper pulp. In this study the use of alternative mineral additions such as expanded perlite, expanded vermiculite, and microspheres as the fillers to paper pulp acquired from waste-paper for the use for the elements of mould sprue/gate systems or also other applications for the contact with liquid metal are presented. Experimental mould tube shapes made on the basis of the paper pulp based mixture patented by the authors were poured over with liquid metal. For the comparison, ceramic shapes and commercially available cellulose shapes were investigated in the same way. In order to compare the crystallization processes, a measurement of the cooling off liquid metal was carried out for all the analysed tube samples. From the so obtained metal samples metallographic microsections were made to compare cast iron microstructures. The results obtained from the investigations carried out have shown that the patented paper pulp based mixture may well be applied as an alternative material used for the elements of the sprue/gate systems for disposable sand moulds.
Źródło:
Advances in Science and Technology. Research Journal; 2015, 9, 26; 83-88
2299-8624
Pojawia się w:
Advances in Science and Technology. Research Journal
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Chitosan and chitosan-polyethylenimine microspheres prepared by membrane emulsification and their application for drug delivery systems
Autorzy:
Wolska, Joanna
Powiązania:
https://bibliotekanauki.pl/articles/1034551.pdf
Data publikacji:
2017
Wydawca:
Sieć Badawcza Łukasiewicz - Polskie Towarzystwo Chitynowe
Tematy:
chitosan
membrane emulsification
microspheres
polyethyleneimine
release
sorption
Opis:
The aim of this paper was to prepare chitosan microspheres characterised by a narrow dispersion of dimensions, suitable for application for drug delivery systems (DDS). The materials, unmodified as well as functionalised using polyethyleneimine were then used for encapsulation of drug-mimicking dyes. The polymeric beads were prepared by one stage process of membrane emulsification. The encapsulation and then evaluation of the release of an active component was carried out using two cytostatics-mimicking dyes: methyl orange and Congo red. The efficiency of encapsulation changed with a type of microspheres and the type of a dye. The highest sorption towards dyes was revealed by PEI-modified chitosan microspheres. Methyl orange was released with the better efficiency than Congo red from all types of microspheres.
Źródło:
Progress on Chemistry and Application of Chitin and its Derivatives; 2017, 22; 220-235
1896-5644
Pojawia się w:
Progress on Chemistry and Application of Chitin and its Derivatives
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Chitosan microspheres prepared by membrane emulsification for chromium removal from aqueous solutions
Autorzy:
Wolska, Joanna
Powiązania:
https://bibliotekanauki.pl/articles/1034646.pdf
Data publikacji:
2016
Wydawca:
Sieć Badawcza Łukasiewicz - Polskie Towarzystwo Chitynowe
Tematy:
biosorption
chitosan
chromium VI
membrane emulsification
microspheres
modification
Opis:
Chitosan is naturally abundant biopolymer that could be used as chelating sorbent for removal of metal ions from aqueous solutions. In this study the uniform-sized chitosan microspheres and their modified derivatives were prepared by using the one stage membrane emulsification process. The obtained sorbents were used for removal of chromium VI ions. The sorption evaluation was carried out at different initial ion concentrations and allowed to fit the experimental data to Langmuir isotherm in the case of unmodified materials and to Freundlich isotherm in the case of modified microspheres. The highest sorption towards chromium has been shown by unmodified chitosan with medium molecular weight. The calculated maximum sorption capacity for this polymer was found to be 1.6 mmol/g.
Źródło:
Progress on Chemistry and Application of Chitin and its Derivatives; 2016, 21; 203-216
1896-5644
Pojawia się w:
Progress on Chemistry and Application of Chitin and its Derivatives
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Qualitative Analyses of Gas Evolution from Modified Cellulose Mixtures During Thermal Degradation in Air and Argon
Autorzy:
Zawieja, Z.
Sawicki, J.
Powiązania:
https://bibliotekanauki.pl/articles/102348.pdf
Data publikacji:
2017
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
expanded perlite
expanded vermiculite
microspheres
cellulose mixture
mass spectrometry
Opis:
This paper presents the application of mineral additives, such as expanded perlite, expanded vermiculite and microspheres in items used in founding. Mixed with paper pulp and aluminosilicate resin as a binder, these additives are the base of a mixture patented by the authors, which can be used in the production of pipe shapes and connectors with a circular cross-section in casting systems in the founding industry. These mixtures were subjected to TG thermal degradation during which a quantitative analysis of the emitted fumes was carried out. The analysis did not detect any other compounds than those formed by the combustion of cellulose materials, which indicated that no chemical reaction took place between the applied additives and cellulose at high temperatures.
Źródło:
Advances in Science and Technology. Research Journal; 2017, 11, 3; 24-30
2299-8624
Pojawia się w:
Advances in Science and Technology. Research Journal
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Związek struktury porowatości betonu napowietrzonego za pomocą mikrosfer z jego mrozoodpornością
The relation between air-pores structure and freeze-thaw durability of air-entrained concretes made with microspheres
Autorzy:
Wawrzeńczyk, J.
Molendowska, A.
Powiązania:
https://bibliotekanauki.pl/articles/362976.pdf
Data publikacji:
2010
Wydawca:
Instytut Fizyki Budowli Katarzyna i Piotr Klemm
Tematy:
beton
mrozoodporność
napowietrzanie
mikrosfery
concrete
freeze resistance
aeration
microspheres
Opis:
W referacie przedstawiono wyniki badań 9 serii betonów BWW napowietrzanych za pomocą mikrosfer polimerowych. Celem badań było okrerślenie związku pomiędzy strukturą porowatości, stosunkiem W/C i mrozoodpornością betonu.
The paper present the results of examinations of 9 series of HCP air-entrained concretes made with microspheres. The aim was to estimate the relastions between air-pores structures, W/B ratio and freeze-thaw durability.
Źródło:
Fizyka Budowli w Teorii i Praktyce; 2010, T. 5, nr 2, 2; 55-58
1734-4891
Pojawia się w:
Fizyka Budowli w Teorii i Praktyce
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Covering glass microspheres with Al2O3 or Aln by low-temperature atomic layer deposition
Pokrywanie mikrosfer szklanych Al2O3 lub AlN metodą niskotemperaturowego osadzania warstw atomowych
Autorzy:
Stankiewicz, R.
Piątkowska, A.
Powiązania:
https://bibliotekanauki.pl/articles/192240.pdf
Data publikacji:
2018
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Technologii Materiałów Elektronicznych
Tematy:
ALD
EDS
dielectric layers
glass microspheres
warstwy dielektryczne
mikrosfery szklane
Opis:
Thin layers of Al2O3 and AlN were deposited on the surface of borosilicate glass microspheres in an ALD reactor at 50 and 150°C, respectively. They were imaged by SEM microscopy. X-ray EDS spectroscopy was used to assess chemical composition but it was also the basis for a thickness determination method. Al2O3 layers between 20 and 100 nm were obtained, with a constant growth rate of 1.2 Å per deposition cycle. AlN formed continuous but always very thin films on the spheres, generally 5 to 10 nm, even if it was growing much thicker on control glass slides, at 0.8 Å per cycle.
W reaktorze ALD osadzano cienkie warstwy Al2O3 i AlN na mikrosferach ze szkła borokrzemowego w temperaturach odpowiednio 50 i 150°c. obrazowano je przy pomocy skaningowego mikroskopu elektronowego. spektroskopia rentgenowska EDs była wykorzystywana do badania składu chemicznego, ale stanowiła także podstawę dla metody wyznaczania grubości warstw. otrzymano warstwy Al2O3 o grubościach od 20 do 100 nm przy stałej szybkości wzrostu 1,2 Å/cykl. AlN tworzył natomiast ciągłe, lecz zawsze bardzo cienkie warstwy (zwykle 5 do 10 nm), mimo że na kontrolnych płytkach szklanych uzyskiwano znacznie większe grubości, a szybkość wzrostu wynosiła 0,8 Å/cykl.
Źródło:
Materiały Elektroniczne; 2018, T.46, nr 1-4, 1-4; 8-15
0209-0058
Pojawia się w:
Materiały Elektroniczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Development of a technology for the production of ceramic moulds with reduced thermal conductivity to control the solidification of thin-walled castings
Autorzy:
Leśniewski, W.
Wawrylak, M.
Wieliczko, P.
Gil, A.
Małysza, M.
Szczepaniak-Lalewicz, K.
Powiązania:
https://bibliotekanauki.pl/articles/391626.pdf
Data publikacji:
2017
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Odlewnictwa
Tematy:
ceramic moulds
aluminium alloys
thermal conductivity
thin-walled castings
microspheres
Opis:
During the project a technology of making ceramic moulds using aluminosilicate microspheres was developed. According to the developed technology, ceramic samples were used to determine thermal conductivity in the temperature range of 500°C to 850°C. In this temperature range, thermal conductivity is about 0.5 W/mK. Strength measurements were conducted using a four-point bending technique. The strength of the developed ceramics and typical ceramics made from molochite materials is similar. Computer simulations facilitated the design of experimental moulds. The recording of Al alloy cooling curves in rectangular insulated and non-insulated moulds allowed for comparison of the thermal parameters of both types of moulds (i.e. ceramics). There was also a castability test performed using the moulds with a “grille” model with 1.5 × 1.5 mm channels, which determined the effect of increased material insulation on the number of properly filled mesh of the mould.
Źródło:
Prace Instytutu Odlewnictwa; 2017, 57, 4; 259-263
1899-2439
Pojawia się w:
Prace Instytutu Odlewnictwa
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
PHYSICOCHEMICAL CHARACTERISTICS OF FUROSEMIDE INCORPORATED EUDRAGIT MICROSPHERES FORMULATED BY SPRAY-DRYING
Autorzy:
Ostróżka-Cieślik, Aneta
Sarecka-Hujar, Beata
Jankowski, Andrzej
Powiązania:
https://bibliotekanauki.pl/articles/895521.pdf
Data publikacji:
2018-12-31
Wydawca:
Polskie Towarzystwo Farmaceutyczne
Tematy:
microspheres
furosemide
Eudragit L30 D-55
spray drying technique
Opis:
Microspheres are one of the multicompartment drug delivery systems. The active substance is incorporated into a polymeric matrix. The aim of the study was to determine physicochemical properties of furosemide microspheres prepared with Eudragit L30 D-55 matrix and to analyse their stability and drug release. A test formulation at the drug-polymer ratio of 1:2 was used in the study. Furosemide was incorporated into the enteric matrix because it reduces gastric acid secretion and impairs gastric secretory functions. The optimum spray drying parameters were determined on the basis of preliminary tests: aspirator efficiency: 80%, Tin: 140°C, pump capacity: 10%. The designated Hausner ratio and Carr index indicate good flow properties of the obtained product. The stability tests show that the microspheres are physically stable under the applied storage conditions. Based on the analysis of furosemide release from microspheres, it has been found that it is a two-step process. In the first step, 28.68% of the active substance was released into a pH 1.2 buffer solution. In the second step, the remaining part of the active substance was released into a pH 6.8 buffer within 30 minutes.
Źródło:
Acta Poloniae Pharmaceutica - Drug Research; 2018, 75, 6; 1369-1376
0001-6837
2353-5288
Pojawia się w:
Acta Poloniae Pharmaceutica - Drug Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Shot Peening With Glass Microspheres on the Fatigue Behavior of a Low Carbon Steel
Autorzy:
de Lacerda, J. C.
Pereira, I. R.
Costa, J. M. G.
Pinto, J. S.
Souza, H. F. M.
Fonseca, M. A.
Powiązania:
https://bibliotekanauki.pl/articles/352156.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
fatigue
shot peening
Wöhler curve
low carbon steel
glass microspheres
Opis:
The present work has the objective of studying the effect of shot peening with glass microspheres on SAE 1020 steel in its resistance to fatigue. Fatigue tests were carried out by rotary bending with load control and loading on balance in specimens with and without shot peening. A rotation speed of approximately 750 rpm (12.5 Hz) was employed in the fatigue tests. Vickers microhardness tests were performed in order to verify the surface hardening produced by shot peening with glass microspheres. Analysis of the steel surface and fatigue fractures was performed using scanning electron microscopy (SEM). Fatigue tests were performed in order to obtain S-N curves (Wöhler curves). It was observed that shot peening with glass microspheres improved the fatigue strength of the steel at high cycle.
Źródło:
Archives of Metallurgy and Materials; 2019, 64, 4; 1513-1518
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł

Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies