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Properties of rubber-like materials and their blends in wide range of temperatures – experimental and numerical study

Konarzewski Marcin, Stankiewicz Michał, Sarzyński Marcin, Wieczorek Marcin, Czerwińska Magdalena, Prasuła Piotr, Panowicz Robert

Acta Mechanica et Automatica

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2023

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Vol. 17, no. 3

317--332

EN

Elastomers are widely used in many industries. Their use requires thorough knowledge of their strength and stiffness parameters over a wide temperature range. However, determination of the parameters of such materials is still a challenge. Therefore, the paper presents research methodology allowing determination of the properties of rubber-like materials in a wide range of stretch and temperatures (from +50°C to 25°C) by using the example of styrene-butadiene rubber (SBR) and natural rubber (NR) elastomers. Additionally, two blends, chloroprene rubber/nitrile-butadiene rubber (CR/NBR) and NR/SBR blends, were also considered. Based on physical premises, a polynomial and Arruda–Boyce hyperelastic constitutive models parameters were determined using two different methods, namely curve-fitting and the successive response surface method.

2

Investigation, analysis and comparison of current-voltage characteristics for Au/Ni/GaN Schottky structure using I-V-T simulation

Sadoun A., Mansouri S., Chellali M., Lakhdar N., Hima A., Benamara Z.

Materials Science Poland

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2019

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Vol. 37, No. 3

496--502

EN

In this work, we have presented a theoretical study of Au/Ni/GaN Schottky diode based on current-voltage (I-V) measurement for temperature range of 120 K to 400 K. The electrical parameters of Au/Ni/GaN, such as barrier height (Φb), ideality factor and series resistance have been calculated employing the conventional current-voltage (I-V), Cheung and Chattopadhyay method. Also, the variation of Gaussian distribution (P (Φb)) as a function of barrier height (Φb) has been studied. Therefore, the modified [formula] relation has been extracted from (I-V) characteristics, where the values of ΦB0 and A+Simul have been found in different temperature ranges. The obtained results have been compared to the existing experimental data and a good agreement was found.

3

Temperaturowe efekty podwójnej fluorescencji 4-(5-heptylo-1,3,4-tiadiazol-2-ilo)benzeno- -1,3-diolu (C7)

Matwijczuk A., Karcz D., Kluczyk D., Matwijczuk A., Gładyszewska B., Niewiadomy A, Gagoś M.

Przemysł Chemiczny

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2017

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T. 96, nr 7

1511--1514

PL

Dokonano pomiarów emisji fluorescencji stacjonarnej dla 4-(5-heptylo-1,3,4-tiadiazol-2-ilo) benzeno-1,3-diolu (C7) w środowisku wodnym. Dla C7 rozpuszczonego w roztworach o niskim pH (poniżej 7) i w zakresie temp. 20-40°C, zaobserwowano dwa wyraźnie rozdzielone pasma emisji fluorescencji. Natomiast dla C7 w tym samym zakresie pH lecz w temp. powyżej 40°C obserwowano już tylko pojedyncze pasmo fluorescencji. W przypadku widm rezonansowego rozpraszania światła RLS obserwowano silny sygnał w zakresie temperatur, w którym widma emisji fluorescencji wykazywały efekt podwójnej fluorescencji. Wraz ze wzrostem temperatury i jednoczesnym zanikiem jednego z pasm fluorescencji, zanikała również intensywność sygnału RLS. Biorąc pod uwagę wcześniejsze badania związków z tej grupy zauważono, że efekty te mogą być związane z efektami agregacyjnymi. Technika spektroskopii fluorescencyjnej umożliwiła szybką analizę zmian molekularnych w badanych związkach, zaowocować to może zaprojektowaniem nowej klasy pochodnych o właściwościach umożliwiających ich potencjalne praktyczne zastosowanie jako sondy fluorescencyjne.

EN

Aq. solns. of 4-(5-heptyl-1,3,4-thiadiazo-2-yl)benzene-1,3-diol (C7) showed two well-resolved fluorescence bands at 20-40°C and pH 1-7. At the temps. exceeding 40°C, only a single fluorescence max. was obsd. The resonance light scattering spectra measured at 20-40°C showed a strong signal, which decreased with the temp. increase. The data were consistent with previous reports and confirmed a mol. aggregation-related nature of the fluorescence effects. The possibility of a quick fluorescence spectroscopy- based anal. of intra- and intermol. transformations was evidenced.

4

Krótki przegląd zastosowań cyklodekstryn dotyczący analiz farmaceutycznych, biomedycznych oraz środowiskowych

Lamparczyk H., Chmielewska A., Zarzycki P. K.

Camera Separatoria

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2013

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Vol. 5, No. 1

27--34

PL

Przedstawiona praca jest ostatnim projektem naukowym nad jakim pracował Profesor Henryk Lamparczyk, który przedwcześnie zmarł 16 listopada 2012 roku w wieku 65 lat. Przeglądowa praca o charakterze dydaktyczno-poglądowym dotyczy zastosowania cyklodekstryn w bioanalityce i została napisana w oparciu o prace opublikowane przez Profesora i współpracowników. Niniejsza wersja bazuje na artykule pt. “Natural cyclodextrins: development in theory, chromatography and pharmacy, A. Chmielewska, H. Lamparczyk;” opublikowanej w materiałach Supramolecular Chemistry and Advanced Materials. Wojciech Macyk & Konrad Szaciłowski, Editors, Kraków Jagielonian University 2007, pages 131-136 i jest rozszerzona o wiadomości przedstawione w najnowszych publikacjach dotyczących zastosowania cyklodekstryn w HPLC, głównie do oznaczeń sterydów i analiz przesiewowych próbek środowiskowych.

EN

This is the last research project of Professor Henryk Lamparczyk that prematurely passed away at age 65. In his intention it was to prepare a demonstrative review paper concerning application of cyclodextrins in bioanalysis, based on his and co-worker contributions to the field of supramolecular chemistry. This version of paper is based on the manuscript entitled “Natural cyclodextrins: development in theory, chromatography and pharmacy, A. Chmielewska, H. Lamparczyk;” that was published in Supramolecular Chemistry and Advanced Materials. Wojciech Macyk & Konrad Szaciłowski, Editors, Kraków Jagielonian University 2007, pages 131-136 and now is extended for the latest papers concerning HPLC application of cyclodextrins for steroids analysis and environmental samples screening. The main tools applied in described investigations were various chromatographic techniques such as gas chromatography (GC), high performance liquid chromatography (HPLC) and thin-layer chromatography (TLC). Topics such as structure-retention relationships, equilibrium constants between cyclodextrins (CDs) and guest molecules, thermodynamics and CDs separations were discussed. Additionally few examples of practical applications of CDs in pharmacy as well as biomedical and environmental analysis are given.

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Effects of Strong Inter-hydrogen Bond Dynamical Couplings in the Polarized IR Spectra of trans-beta-Hydromuconic Acid Crystals

Flakus H. T., Jabłońska M., Tyl A.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 5

869-886

EN

This paer presents the re sults of in ves ti ga tions of po lar ized IR spec tra of trans-beta hydromuconic acid (HMA) crystals. The spectra were measured by a transmission method using polarized light at room temperature and at 77 K for three different crystalline faces. Theoretical analysis of the results concerned linear dichroic effects, H/D iso topic and temperature effects observed in the spectra of the hydrogen and deuterium bonds in HMA crystals at the frequency ranges of the ni O–H and the ni O–D bands. The basic crystal spectral properties could be sat is factorily interpreted in a quantitative way for a centrosymmetric cyclic hydrogen bond dimer model. Model calculations, performed within the limits of the “strong-coupling” model, al lowed for quantitative interpretation and for the under standing of the basic properties of the hydrogen bond IR spectra of HMA crystals including H/D isotopic, temperature and dichroic effects. Such a model explains not only the two-branch structure of the ni O–H and ni O–D bands in crystalline spectra, but also some essential linear dichroic effects in the band frequency ranges measured for isotopically diluted HMA crystals. In the scope of our studies the mechanism of H/D isotopic “self-organization” processes, taking place in the crystal hydrogen bond lattices, was also studied. It was proved that for isotopically diluted crystalline samples of HMA, a non-random distribution of protons and deuterons occurs exclusively in the hydrogen bond dimers. Never the less, these dynamical co-operative inter actions between the hydrogen bonds do not in volve of the adjacent hydrogen bond dimers in each unit cell. The two-branch fine structure pattern of the ni O–H and ni O–D bands was ascribed to the vibronic mechanism of vibra tional di pole se lec tion rule break ing for IR tran si tions in centrosymmetric hy dro gen bond dimers. The lin ear dichroic ef fect, dif fer en ti at ing properties of the two op po site spec tral branches of the nO–H and nO–D bands, was also discussed.

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Effects of laser radiation on the cementitious materials - three case studies

Klemm A. J., Rożniakowski K.

Fizyka Budowli w Teorii i Praktyce

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2009

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T. 4

79-84

EN

Laser processing is unarguably associated with some alterations of cementitious materials' geometrical microstructure and chemical composition. Since high temperature is involved in the laser cleaning process, the chemical composition of surfaces may change, followed by crack development and subsequent changes of roughness. The relationship between laser treatment and substrate parameters is a two-way relationship. The great variation in absorptivity of highly developed surfaces of cementitious materials results in substantial differences in their responses to laser irradiation. Paper presents selected results of three investigations on the effect of laser radiation on characteristics of porous cementitious materials.

7

Deformacja hiperboidalnej chłodni od wpływu temperatury: rozwiązanie analityczne i numeryczne

Jankowiak R., Baran W., Jędraszak B.

Systems : journal of transdisciplinary systems science

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2004

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Vol. 9, No. sp. II

486-495

PL

Praca poświęcona jest przemieszczeniom hiperboloidalncj chłodni kominowej poddanej działaniu pola temperatur. Dla modelu liniowo-sprężystego podano rozwiązanie analityczne i numeryczne. Opracowano własne, oryginalne procedury obliczające zapisane w języku FORTRAN, które posłużyły do uzyskania rozwiązania analitycznego. Identyfikację wyników przeprowadzono wykor/ystując pakiet Robot.

EN

Displacements of hyperboloidal cooling tower subjected to temperature load is discussed in the paper. Linear elastic material model is assumed. Results of analytical and numerical analysis are presented. Analytical results were obtained using own orginaJ computer procedures prepared using FORTRAN programming language. The results were verified thanks to application of software system for numerical computations called Robot.

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Investigation of Polarized Infrared Spectra of the Hydrogen Bond in Molecular Crystls. New Spectra Effects in the Vibrational Spectroscopy of Hydrogen Bonded Systems

Flakus H.

Polish Journal of Chemistry

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2003

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Vol. 77 / nr 5

489-517

EN

Areview of the experimental as well as of the theoretical studies, performed on the area of the infrared spectroscopy of hydrogen bonded molecular crystals, is given. Discussion of some physical phenomena is presented, responsible for basic spectral effects registered in the infrared spectra, as breaking of vibrational dipole selection rules in the IR spectra, linear dichroic as well as temperature effects, observed in the frequency range of the proton stretching vibrations. Also some newly recognized H/D isotopic effects for hydrogen bonded systems are presented, deduced from a quantitative analysis of the polarized spectra in the IR, namely the so called isotopic "self-organization" effects and the "long-range" H/D isotopic effects.

9

Study on the mechanism of enantioseparation. Part V. HPLC chiral analysis of alkoxysubstituted esters of phenylcarbamic acid on ß-cyclodextrin stationary phase

Hroboňová K., Lehotay J., Čižmárik J.

Chemia Analityczna

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2003

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Vol. 48, No. 3

473-482

EN

Chemically bonded Beta-cyclodextrin was used as a chiral stationary phase for the reversed phase HPLC enantiomeric separation of 1 -methoxymethy 1, 1 -ethoxymethyl, 1 -propoxyme-thyl-2-(l-pyrrolidinyl), (1-piperidino) and (1-perhydroazepinyl)-ethyl esters of 2-alkoxy-phenylcarbamic acid. The influence of temperature and the structure of investigated compounds on the enantioseparation were studied. The type of nitrogen substituent in the hy-drophilic part of the molecule and the length of the chain (connecting hydrophilic and lipo-philic parts of the molecule) did not influence the separation significantly. In contrast, the length of the alkoxy substituent and its position with respect to the stereogenic centre were of great importance to the quality of the separation. Lower temperatures favoured the increase of the retention of studied enentiomers and improved their separation. The linear dependence between the logarithm of the retention factor (Ink) and the inverse of the temperature (1 AT) was observed. Thermodynamic parameters (standard enthalpy change, standard entropy change, and Gibbs free energy) were also determined.

PL

Chemicznie związaną Beta cyklodekstrynę zastosowano jako chiralną fazę stacjonarną w rozdzielaniu enancjomerów 1-metoksymetylo, 1-etoksymetylo, 1-propoksymetylo-2-(1-piroli-dynyl), 1-piperydyno, 1-perhydroazepinylo-etylowych estrów kwasu 2-alkoksyfenylokarbaminowego w układzie faz odwróconych. Badano wpływ struktury tych związków i wpływ temperatury na rozdzielanie enancjomerów. Rodzaj podstawnika azotowego w hydrofilowej części cząsteczki i długość łańcucha łączącego hydrofilową i lipofilową część cząsteczki nie mają istotnego wpływu na rozdzielanie enancjomerów. Istotny wpływ na rozdzielanie ma długość podstawnika alkoksylowego w pierścieniu aromatycznym i jego położenie względem centrum przestrzennego. Obniżenie temperatury powoduje wzrost retencji badanych związków i rozdzielania enancjomerów. Logarytmy współczynników retencji (In K) badanych związków zależą liniowo od odwrotności temperatury (l/T). Wyznaczono też parametry termodynamiczne (zmiana standardowej entalpii, zmiana standardowej entropii, swobodna energia Gibbsa).

10

Badania procesu oksydacyjnego odsiarczania węgla. Cz. I. Wpływ temperatury i czasu reakcji

Pyszjew S. W., Gajwanowicz W. I., Surygała J.

Karbo

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2001

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Nr 1

6-11

PL

Prowadzono badania nad oksydacyjnym odsiarczaniem węgli ukraińskich z Zagłębia Donieckiego i Lwowsko-Wołyńskiego. Oceniono wpływ temperatury (573-748 K) i czasu reakcji (5-90 min) na stopień eliminacji siarki, wydajność produktów oraz skład gazów z odsiarczania. Stopień odsiarczania zależy od rodzaju surowca, ale najkorzystniejsze rezultaty uzyskuje się w wyższych temperaturach i krótszych czasach reakcji. Stopień usunięcia siarki pirytowej przekracza wówczas 90 %. W wyniku badań ustalono optymalny zakres temperatury odsiarczania na 673-723 K, a czas reakcji 30-60 min.

EN

The investigations have been conducted on oxidising desulphurisation of Ukrainian coals from Donietzk and Lvov - Volyn Coal Basins. The influence of temperature (573-748 K) and reaction time (5-90 min) upon the degree of sulphur elimination was determined, yield of products and composition of gases from sulphurisation. The sulphurisation degree depends on the kind of raw material but the best results are obtained at higher temperatures and in shorter reaction time. When the degree of pyrite sulphur removal exceeds 90 %. As the results of investigation optimum range of desulphurisation temperature was determined at 673-723 K, and reaction time at 30-60 min.

11

Effect of temperature on manganese II-ion-catalyzed bromate-driven oscillators

Rachwalska M.

Bulletin of the Polish Academy of Sciences. Chemistry

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1998

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Vol. 46, No. 4

459-467

EN

In this paper the system: Mn2(+)-malonic acid-H2504-KBrO3 was investigated. The reaction occurred in a state far from equilibrium because a flow-through reactor was used. By measuring the platinum electrode potential and bromide ion selective electrode potential for the system studied a bifurcation diagram was obtained. Many various concentrations of reactants were used. After obtaining the bifurcation diagram, such a set of reactants' concentrations was investigated at various temperatures for which the reaction had an oscillatory character. Basing on these results it was possible to estimate the activation energy of the reaction as equal to 47.8 = 5.3 kJ/mol. It was found that under CSTR conditions Q(10) values become as low as 1.6. For two sets of initial concentrations an anomalous behavior of the oscillation period was observed. In this case the period of oscillation does not decrease when increasing the temperature but increases.

12

Conformational temperature effects in deacetylcephalothin investigated by experimental and simulated H NMR

Zimniak A., Oszczapowicz I., Sikora A., Wawer I.

Bulletin of the Polish Academy of Sciences. Chemistry

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1998

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Vol. 46, No. 2

179-183

EN

Temperature-dependent difference between chemical shifts in AB proton system due to the conformational transition have been observed in cephalosporin deacetylcephalothin. To exclude the possibility of the dynamic process the experimental and simulated spectra were compared.