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Tytuł:
Kinetics of Zinc Evaporation in Inert and Reducing Gases
Autorzy:
Łabaj, J.
Powiązania:
https://bibliotekanauki.pl/articles/352863.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
evaporation
flux
zinc
thermogravimetric analysis
Opis:
The article presents the results of studies on the rate of zinc evaporation in the atmosphere of helium and carbon monoxide (II) carried out with the thermogravimetric method. The estimated values of zinc streams were compared with the values determined based on theoretical relationships.
Źródło:
Archives of Metallurgy and Materials; 2018, 63, 2; 533-537
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Radiograficzne i termograwimetryczne badania pirolizy pojedynczej cząstki drewna
Pyrolysis analysis of a single wood particle
Autorzy:
Kaźmierski, P.
Wardach-Święcicka, I.
Tiutiurski, P.
Kardaś, D.
Powiązania:
https://bibliotekanauki.pl/articles/2073378.pdf
Data publikacji:
2017
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
piroliza
radiografia
termograwimetria
pyrolysis
radiography
thermogravimetric analysis
Opis:
Opisano proces pirolizy pojedynczej cząstki drewna. Za pomocą termograwimetrii, badań w piecu wysokotemperaturowym oraz metod radiograficznych przeprowadzono analizę procesu pirolizy. Analizowano szybkość dekompozycji termicznej i jej stopień w funkcji czasu. Badano poddane pojedyncze próbki w formie sosnowych sześcianów o boku 18 mm. Analiza termograwimetryczna mająca na celu wyznaczenie przedziałów, w jakich zachodzi proces, poprzedziła badania wykonane w piecu wysokotemperaturowym. Próbki po eksperymentach zostały poddane badaniom radiograficznym celem zobrazowania zmian gęstości drewna w funkcji czasu. Na zdjęciach zaobserwowano, iż piroliza zachodzi od naroży próbki, a następnie pozostaje tylko niespirolizowany rdzeń w środku próbki. Badania potwierdziły duże możliwości radiografii w ocenie pirolizy.
Pyrolysis process of a single wood particie is described in the paper. Thermogravimetric and radiography techniques and pyrolysis in a high-temperature kiln were applied in the experiments. The thermal decomposition rate as a function of time was analyzed. Pine cubes with a side of 18 mm were used as samples. High-temperature kiln tests were preceded by thermogravimetric analysis aiming to determine temperature ranges in which the process took place. The samples after tests were analyzed using radiographic methods to visualize the changes in wood density as a function of time. It was observed on the photographs that pyrolysis started from sample corners, while only a core in the center of samples remained unchanged. Radiography experiments have a big potential in pyrolysis research.
Źródło:
Inżynieria i Aparatura Chemiczna; 2017, 6; 202--204
0368-0827
Pojawia się w:
Inżynieria i Aparatura Chemiczna
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Thermal decomposition characterization of supergene potassium-jarosite and sodium-jarosite minerals from the northern Tibetan Plateau, China
Autorzy:
Chen, L.
Powiązania:
https://bibliotekanauki.pl/articles/949691.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
potassium-jarosite
sodium-jarosite
thermogravimetric analysis
X-ray diffraction
Opis:
The thermal decomposition of supergene potassium-jarosite and sodium-jarosite samples from the weathering profiles of sulfide deposits in the northern Tibetan Plateau, China, was investigated. Electron microprobe, scanning electron microscopy, and X-ray diffraction analyses indicated the presence of nearly pure potassium-jarosite and sodium-jarosite. Thermogravimetric analysis of the potassium-jarosite sample revealed mass losses of 11.39 wt% at 443.0 °C, 20.99 wt% at 688.3 °C, and 3.18 wt% at 779.3 °C. The thermogravimetric analysis of sodium-jarosite revealed mass losses of 11.72 wt% at 447.5 °C, 21.32 wt% at 682.6 °C, and 3.70 wt% at 716.5 °C. The results provide no evidence for water-molecule loss below 400 °C, as has been reported previously for natural potassium-jarosite and sodium-jarosite. Thermal-decomposition mechanisms have been proposed for potassium-jarosite and sodium-jarosite based on X-ray diffraction analyses of samples obtained at distinct points along the respective thermal decomposition processes. A comparison of the thermal analysis patterns of potassium-jarosite and sodium-jarosite indicates that sodium-jarosite undergoes the initiation of lattice destruction at a higher temperature.
Źródło:
Physicochemical Problems of Mineral Processing; 2018, 54, 2; 459-466
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synthesis and Study of the Thermal and Ballistic Properties of SMX
Autorzy:
Sizov, V. A.
Pleshakov, D. V.
Asachenko, A. F.
Topchiy, M. A.
Nechaev, M. S.
Powiązania:
https://bibliotekanauki.pl/articles/358831.pdf
Data publikacji:
2018
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
tetranitrate ester
burning rate
differential scanning calorimetry
decomposition
thermogravimetric analysis
Opis:
The high-density tetranitrate ester 1,4-dinitrato-2,3-dinitro-2,3-bis(nitratomethylene)butane (SMX) was synthesized. The methods of obtaining and isolating the intermediates were optimized. The differences between the syntheses of SMX by a four- and five-step scheme were investigated. Combustion of SMX and its catalysis was studied. The possibility of replacing NG as the main plasticizer in a double-base propellant composition was demonstrated. SMX particles were shown to have pronounced crystal faceting using scanning electron microscopy. The decomposition rate equation was determined. The amount of SMX decomposed under isothermal conditions (90 °C) was 0.8 wt.% after 60 min. Thermogravimetric analysis demonstrated that heating SMX results in two different processes – decomposition and evaporation, with SMX evaporating faster than it decomposes.
Źródło:
Central European Journal of Energetic Materials; 2018, 15, 1; 30-46
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mechanism and kinetics oxidation of inconel 617 and 625 alloys
Autorzy:
Staszewska, K.
Scendo, M.
Powiązania:
https://bibliotekanauki.pl/articles/134738.pdf
Data publikacji:
2016
Wydawca:
ADVSEO
Tematy:
inconel alloy
thermogravimetric analysis
thermodynamic parameters
parabolic rate constants
activation energy
Opis:
The mechanism and kinetics of oxidation of Inconel 617 and 625 alloys in air atmosphere were investigated. Materials were examined by the thermogravimetric method. The X-ray diffraction spectrometer (XRD) was used to observation change in chemical composition the oxide scales of Inconel alloys specimens. Oxidation kinetics was determined from weight-change measurements. The surface and microstructure of the sample were observed in an optical microscope (OM) and a scanning electron microscope (SEM). The results showed that the oxide scales of the alloys were compact and continuous. The layer were contained as the outer of Cr2O3, and the internal of NiCr2O4 spinel, NiO and other oxides. Oxides’ scales with good adherence were formed on the surface of alloys. The kinetics and thermodynamic parameters of oxides formation were calculated and discussed for both alloys.
Źródło:
Technical Issues; 2016, 1; 82-89
2392-3954
Pojawia się w:
Technical Issues
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wpływ temperatury na bilans węgla, wodoru oraz azotu w produktach pirolizy odpadowych zrębek brzozowych
Effect of temperature on the balance of carbon, hydrogen and nitrogen in pyrolysis products
Autorzy:
Kazimierski, P.
Kardaś, D.
Powiązania:
https://bibliotekanauki.pl/articles/2072930.pdf
Data publikacji:
2016
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
piroliza
dekompozycja biomasy
bioolej
analiza termograwimetryczna
pyrolysis
biomass decomposition
bio-oil
thermogravimetric analysis
Opis:
Przeprowadzono badania pirolizy zrębków brzozowych v reaktorze laboratoryjnym w 300, 400 oraz 500°C. Badania w reaktorze poprzedzono testami termograwimetrycznymi. produkty pirolizy podzielono na pięć części: karbonizat, woda, gaz, smoły lekkie i smoły ciężkie. Określono udziały masowe każdej frakcji w zależności od temperatury. Oznaczono zawartości węgla, wodom oraz tlenu za pomocą analizatora elementarnego. Ilościowy skład frakcji niskowrzącej oznaczono chromatograficznie za pomocą GC-MS, a frakcji gazowej za pomocą GC-TCD.
Experiments on birch wood pyrolysis in a laboratory-scale batch reactor at temperatures 300, 400 and 500°C were performed. The investigations were preceded by thermogravimetric tests. Pyrolysis products were separated into five fractions: gases, tar, water, char and low-boiling liquid fraction. The mass concentrations of each fraction as a function of temperature were found. The content of carbon, hydrogen and nitrogen were determined using an elementary analyser. The quantitative composition of low-boiling fraction was determined using GC-MS, while the gas fraction - using GC-TCD.
Źródło:
Inżynieria i Aparatura Chemiczna; 2016, 3; 97--99
0368-0827
Pojawia się w:
Inżynieria i Aparatura Chemiczna
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A comparison of thermogravimetric characteristics of fresh and used engine oils
Autorzy:
Kozak, Miłosław
Powiązania:
https://bibliotekanauki.pl/articles/133176.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Naukowe Silników Spalinowych
Tematy:
engine oil
thermogravimetric analysis
TGA
soot content
olej silnikowy
analiza termograwimetryczna
zawartość sadzy
Opis:
The requirements set for engine oils are nowadays very high, varied, often contradictory and significantly go beyond the classic functions of engine oils. Also for the testing of engine oils, many different and advanced research methods are currently used. This article describes tests of fresh and used oil from a diesel engine using thermogravimetric analysis. This method was also used to determine the soot content of the used oil. The tests showed that the thermograms of fresh and used oil are similar, however in the oil used in the diesel engine the soot content increases.
Źródło:
Combustion Engines; 2019, 58, 3; 289-292
2300-9896
2658-1442
Pojawia się w:
Combustion Engines
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Halloysite intercalated by potassium acetate
Autorzy:
Mariusz, Adamczyk
Katarzyna, Małycha
Karol, Kułacz
Michał, Pocheć
Kazimierz, Orzechowski
Powiązania:
https://bibliotekanauki.pl/articles/1450347.pdf
Data publikacji:
2020
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
clay minerals
electron microscopy
XRD
X-ray diffraction
TGA
thermogravimetric analysis
dielectric spectroscopy
Opis:
Halloysite was intercalated by the mechanochemical technique from dry components. The process efficiency of 50% was achieved. The obtained intercalate differed from the material acquired using an aqueous solution of potassium acetate. The material was analyzed employing electron microscopy, thermogravimetry, X-ray powder diffraction, and dielectric spectroscopy. It was found that the molecules and/or ions present in the interlayer spaces retain some possibility of movement. This property of the material is promising for potential application as low expensive absorbers of electromagnetic radiation.
Źródło:
Physicochemical Problems of Mineral Processing; 2020, 56, 6; 235-243
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Polypropylene matrix composite with charcoal filler
Autorzy:
Polok-Rubiniec, M.
Włodarczyk-Fligier, A.
Powiązania:
https://bibliotekanauki.pl/articles/1818810.pdf
Data publikacji:
2020
Wydawca:
Stowarzyszenie Komputerowej Nauki o Materiałach i Inżynierii Powierzchni w Gliwicach
Tematy:
composite
polymer composites
charcoal filler
thermogravimetric analysis
resistivity
kompozyt
kompozyty polimerowe
analiza termograwimetryczna
rezystywność
Opis:
Purpose: The aim of the article is to present the thermal, electrical and mechanical properties of the produced polymer composites with a filler in the form of charcoal powder. Design/methodology/approach: The tests were carried out on samples of pure polypropylene (PP) and polymer composites, the matrix of which is polypropylene (PP), and the filler was charcoal powder with a volume fraction of 10%, 20%, 30%, 40% and 50%. The tested polymer composites in the form of granules were produced by extrusion, and then standardised test profiles were made by injection moulding. Findings: The hardness of the tested composites was determined by the Shore D method, the grain size distribution of the filler used was determined using the laser method and its thermal stability was tested using the TGA thermogravimetric analysis. The volume and surface resistivity were also determined and the density was determined. It was found that the charcoal powder used as a filler is characterised by high thermal stability - up to 600°C - and with an increase in its volume share in the polymer matrix, the hardness and density of the produced composites increases. Practical implications: The tested composites can be used as structural composites for complex elements requiring high hardness and strength. Originality/value: The research results indicate the possibility of using charcoal as a filler in polymer matrix, which, due to its low production cost, may be an alternative to expensive carbon fillers.
Źródło:
Journal of Achievements in Materials and Manufacturing Engineering; 2020, 103, 2; 60--66
1734-8412
Pojawia się w:
Journal of Achievements in Materials and Manufacturing Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Badanie wpływu struktury chemicznej na stabilność termiczną N-halaminowych pochodnych hydantoiny
Autorzy:
Chylińska, M.
Kaczmarek, H.
Powiązania:
https://bibliotekanauki.pl/articles/279096.pdf
Data publikacji:
2017
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Inżynierii Materiałów Polimerowych i Barwników
Tematy:
N-halaminy
hydantoiny
stabilność termiczna
analiza termograwimetryczna
N-halamine
hydantoins
thermal stability
thermogravimetric analysis
Źródło:
Przetwórstwo Tworzyw; 2017, T. 23, Nr 1 (175), 1 (175); 5
1429-0472
Pojawia się w:
Przetwórstwo Tworzyw
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Determination of kinetic parameters of coal pyrolysis to simulate the process of underground coal gasification (UCG)
Autorzy:
Urych, B.
Powiązania:
https://bibliotekanauki.pl/articles/92059.pdf
Data publikacji:
2014
Wydawca:
Główny Instytut Górnictwa
Tematy:
underground coal gasification
pyrolysis
thermogravimetric analysis
kinetic parameters
podziemne zgazowanie węgla
piroliza
analiza termograwimetryczna
parametry kinetyczne
Opis:
Purpose The aim of the research presented in this paper was to determine the values of the kinetic parameters of coal pyrolysis from two areas of the planned experiment, UCG, i.e. the Barbara Experimental Mine of the Central Mining Institute and the Wieczorek Mine. Methods The thermal decomposition of coal analysis used the thermogravimetric technique. The test was carried out in a temperature range of 298-1173 K in a nitrogen atmosphere for three fixed heating rates, β – 5, 10, and 15 K/min. A selection of sample heating rates of coal and reaction environments were designed to reflect the conditions seen during the process of underground coal gasification. The kinetic parameters were determined by using modified Coats-Redfern, Kissinger and Mianowski-Radko methods. Results The values of the activation energy, E, and the pre-exponential factor, A, were determined for a given model of the first order decomposition reaction of coal. The study successfully compared kinetic parameters of the tested coals. Practical implications Designated kinetic parameters may be used to model the process of pyrolysis and – as preliminary data – for installation design of pilot underground coal gasification. Originality/ value The devolatilization of a homogenous lump of coal is a complex issue. Currently, the CFD technique (Computational Fluid Dynamics) is commonly used for the multi-dimensional and multiphase phenomena modelling. The mathematical models, describing the kinetics of the decomposition of coal, proposed in the article can, therefore, be an integral part of models based on numerical fluid mechanics.
Źródło:
Journal of Sustainable Mining; 2014, 13, 1; 3-9
2300-1364
2300-3960
Pojawia się w:
Journal of Sustainable Mining
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
In situ methanolic solvent synthesis, spectroscopic and thermogravimetric characterizations of three new transition metal complexes of trimethoprim drug
Autorzy:
Refat, Moamen S.
Al-Humaidi, Jehan Y.
El-Sayed, Mohamed Y.
Hassan, Reham F.
Powiązania:
https://bibliotekanauki.pl/articles/1849325.pdf
Data publikacji:
2021
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
complexation
trimethoprim
transition metals
TGA
thermogravimetric analysis
FTIR
Fourier transform infrared spectroscopy
ESR
kinetic thermodynamic parameters
Opis:
Trimethoprim drug (TMP) complexes of copper (II), cobalt (II), and nickel (II) were prepared and discussed by using elemental analysis (C, H, N analysis), magnetic, molar conductance, FTIR, Raman spectroscopy, electron spin resonance (ESR) and UV-vis spectroscopy analyses. TMP drug coordinated as a tridentate ligand towards the respected three metal ions through two nitrogen atoms of amino groups and nitrogen atom of pyrimidine ring which flanked between –NH2 groups, these assignments confirmed by spectroscopic, magnetic, ESR and thermogravimetric analyses with formulas [Cu(TMP)(H2O)3]Cl2, [Co(TMP)(H2O)3]Cl2 and [Ni(TMP) (H2O)]Cl2. Copper (II) and cobalt (II) complexes have an octahedral geometrical structure included one TMP molecule, three coordinated water molecules and two uncoordinated chlorine atoms while, nickel(II)–TMP complex has a tetrahedral geometric configuration that involved one TMP molecule, one coordinated water molecule and two uncoordinated chlorine atoms. The activation energies and other kinetic thermodynamic parameters were estimated based on the employed of the Coats-Redfern and Horowitz-Metzger equations. The nano–structured form of the synthesized TMP complexes was confirmed dependent on the transmission electron microscopy (TEM).
Źródło:
Polish Journal of Chemical Technology; 2021, 23, 1; 60-67
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modification of the Surface of the Iron Powder as an Ingredient of the High Calorific Mixture
Autorzy:
Czajka, B.
Wachowski, L.
Łapiński, A.
Rzodkiewicz, W.
Powiązania:
https://bibliotekanauki.pl/articles/358561.pdf
Data publikacji:
2008
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
iron powder
Fe-KClO4 mixture
Raman spectroscopy (RS)
ellipsometry
thermo-programmed reduction (TPR)
thermogravimetric analysis
TG/DTA
Opis:
Textural properties of iron powders obtained by reduction of iron(II) compounds and by electrolysis were determined. Their specific surfaces were 0.38 and 0.43 m2g-1 respectively, and the prevailing grain sizes amounted to 10 and 43 ?m respectively. Total content of the determined metallic impurities was 0.055 wt.% in the preparation obtained by the electrolysis while in the preparation obtained by reduction it was 0.025 wt.%. It was proved that in initial samples the α-Fe2O3 phase occurred in the outer oxide layer present on the surface of Fe grains, and below this phase a layer of magnetite was found, the thickness of which was considerably greater in iron obtained by electrolysis. Measurements of selected properties showed that modification of the iron powder surface carried out by reduction with dihydrogen led to decreasing the linear rate of burning of the high calorific mixture Fe/KClO4 but it did not affect its calorific value. Moreover, it was found that modification of the iron powder surface resulted in lowering the temperature of ignition of the analysed mixture and decreasing the quantity of the released oxygen generated by decomposition of the oxidant, which did not react with the iron powder.
Źródło:
Central European Journal of Energetic Materials; 2008, 5, 3-4; 87-102
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Catalytic pyrolysis of rice straw and product analysis
Autorzy:
Song, C.
Pawłowski, A.
Ji, J.
Shan, S.
Cao, Y.
Powiązania:
https://bibliotekanauki.pl/articles/207442.pdf
Data publikacji:
2014
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
thermogravimetric analysis
catalytic pyrolysis
effect of addition
pyrolysis products
rice straw
analiza termograwimetryczna
piroliza katalityczna
piroliza
produkty pirolizy
słoma ryżowa
Opis:
The effect of addition of NaOH on the pyrolysis of rice straw and properties of its product were investigated. The pyrolysis was examined by means of the thermogravimetric (TG) analysis, and the pyrolysis product was characterized by the elemental analysis, GC and GC-MS. The result showed that addition of NaOH can significantly change TG and DTG peak of the pyrolysis of rice straw. As a result of the catalysis, significant difference in the properties of pyrolysis products was also observed. The addition of the catalyst promoted the increase of the hydrogen content of the gaseous product (from 1.6% to 53.37%), as well as that of the H/C and O/C ratios of solid residue. GC-MS analysis indicated that the liquid product was mainly made up of ketones, phenols and furfural, and NaOH addition did not change the main constitute of the liquid product, but changed their relative content.
Źródło:
Environment Protection Engineering; 2014, 40, 1; 35-43
0324-8828
Pojawia się w:
Environment Protection Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synteza, charakterystyka, właściwości termiczne i elektrochemiczne polimerów iminowych zawierających jednostki pirydynowe i pirymidynowe
Synthesis, characterization, thermal and electrochemical properties of imine polymers containing pyridine and pyrimidine units
Autorzy:
Karaer, H.
Kaya, I.
Aydın, H.
Powiązania:
https://bibliotekanauki.pl/articles/947552.pdf
Data publikacji:
2017
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Chemii Przemysłowej
Tematy:
poli(iminy)
poli(fenoksy-iminy)
właściwości optyczne
analiza termograwimetryczna
półprzewodnictwo
poly(imines)
poly(phenoxy-imines)
optical properties
thermogravimetric analysis
semiconductivity
Opis:
Polizasady Schiffa zsyntetyzowano metodą polimeryzacji utleniającej 2-hydroksybenzaldehydu (2-HBA) w środowisku alkalicznym, w obecności NaOCl jako utleniacza, a następnie szczepiono otrzymany polialdehyd za pomocą amin zawierających grupy pirydynowe i pirymidynowe. Uzyskane polimery charakteryzowano metodami GPC i SEM, a ich struktury potwierdzono za pomocą spektroskopii FT-IR, 1H NMR, 13C NMR i UV-Vis. Właściwości optyczne polizasad Schiffa analizowano spektroskopią fluorescencyjną i UV-Vis, a właściwości termiczne określono metodami TG, DTA i DSC. Korzystając z woltamperometrii cyklicznej (CV) oraz pomiarów przewodności ciała stałego metodą czteropunktową badano właściwości elektrochemiczne otrzymanych polimerów. Pomiary te wskazują na półprzewodnikowy charakter polimerów. Stwierdzono, że wartości liczbowo średniego ciężaru cząsteczkowego (Mn), wagowo średniego ciężaru cząsteczkowego (Mw) i stopnia polidyspersji (Đ) poli(2-hydroksybenzaldehydu) (P-2HBA) wyznaczone na podstawie analizy GPC są równe, odpowiednio, 5900, 5450 oraz 1,08. Szerokość elektrochemicznej przerwy energetycznej (E'g) oznaczono metodą CV, natomiast szerokość optycznej przerwy energetycznej (E'g) za pomocą spektroskopii UV-Vis.
Schiff bases polymers were synthesized from 2-hydroxybenzaldehyde (2-HBA) via oxidative polymerization method in an aqueous alkaline medium in the presence of NaOCl as an oxidant. Then, these polymeric Schiff bases were prepared from the polyaldehyde by grafting each of them with different amines containing pyridine and pyrimidine groups. The structures of polymers were confirmed by FT-IR, 1H NMR, 13C NMR, and UV-Vis measurements. The polymers were characterized by GPC and SEM analyses. Furthermore, their optical properties were determined by UV-Vis and fluorescence spectroscopy, their electrochemical properties by cyclic voltammetry (CV) analysis and solid state conductivity measurements by the four-point probe technique, their thermal behavior by TG, DTA, and DSC measurements. The electrical conductivity of the polymers was also measured and found that they are semiconductive. The number average molecular weight (M'n), the weight average molecular weight (M'w), and dispersity (Đ) values of the polymers were found from GPC analysis and were equal 5900, 5450 and 1.08, respectively, for poly(2-hydroxybenzaldehyde) (P-2HBA) polymer. Electrochemical energy gap (E'g) was found by CV, whereas optical band gap (E'g) was determined by UV-Vis measurements.
Źródło:
Polimery; 2017, 62, 3; 170-180
0032-2725
Pojawia się w:
Polimery
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 26

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