Wyniki wyszukiwania - Biblioteka Nauki

1

Photoconducting Properties of Fullerene Derivatized with a Biphenyl Moiety

100%

Trzcińska K. , Bilkova P. , Szydłowska J. , Mieczkowski J. , Bilewicz R. , Pociecha D. , Gorecka E.

Polish Journal of Chemistry

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2006

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tom Vol. 80, nr 11

1899-1907

EN

The properties of low molecular weight molecules, in which the electron-acceptor fullerene unit was linked by malonate group and flexible long alkyl chains to two biphenyl-phenyl units, were studied. Cyclic voltammetry measurements showed five consecutive one-electron, reversible electro-reductions for the fullerene unit and a single two-electron, reversible electro-oxidation for biphenyl moiety. The two electron process indicated that two biphenyl moieties interacted; presumably folded conformation was formed with two electron donating moieties at close proximity. Along-living charge-separated state induced upon light absorption was confirmed by the ESR spectroscopy studies. These properties were responsible for observed photoconductivity of the studied compound.

2

Molecular dynamics of hypoxanthine-3-N-oxide near fullerene "sphere" - a computer simulation

80%

Raczyński P. , Pałucha S. , Brol P. , Gburski Z.

Materials Science Poland

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2005

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tom Vol. 23, No. 3

591--598

EN

A computer simulation (MD method) study is presented for a nanosystem composed of a limited number (n = 15, 25, 35) of hypoxanthine-3-N-oxide (H3NO) molecules surrounding a single fullerene molecule. The calculations were performed for several temperatures and densities (solid and fluid phases of hypoxanthine-3-N-oxide thin layers). The mean square displacement, diffusion coefficient, linear and angular velocity autocorrelation functions and their Fourier transforms have been obtained for H3NO.

3

Molecular dynamics study of the fullerene-cholesterol mixture cluster

80%

Raczynski P. , Dawid A. , Gburski Z.

Materials Science Poland

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2005

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tom Vol. 23, No. 2

441--446

EN

Molecular dynamics MD) studies are presented for clusters composed of fullerene and cholesterol molecules. Several quantities of fullerene and cholesterol as a function of temperature have been dynamically investigated. The mean square displacement, diffusion coefficient, angular and linear velocity autocorrelation functions of both fullerene and cholesterol have been calculated. It has been shown the existence of both a solid and liquid phases of the cholesterol layer surrounding the fullerene "core". The translational diffusion of cholesterol molecules in the liqud phase significantly increase as the temperature rises. Moreover, the plastic phase of the fullerene "core" has been detected.

4

Method to obtain carbon nano-onions by pyrolisys of propane

80%

Garcia-Martin T. , Rincon-Arevalo P. , Campos-Martin G.

Open Physics

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2013

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tom 11

|

nr 11

1548-1558

EN

We present a new and simple method for carbon nano-onions (CNOs) production which is based on the pyrolysis of Propane. CNOs are originated in a laminar premixed Propane/Oxygen flame of approximately 1.8 of stoichiometric coefficient. The stream of gasses resulting from the combustion drives the carbon particles towards the aluminium surface on which nano-onions are deposited and collected. The structure and size of the deposited carbon onion on the metal wall are characterized by High Resolution Transmission Electron Microscopy technique (HRTEM). The experimental images show the presence of two different types of CNOs. The first particles have diameters in the range of 18-25 nm and the second ones around 10 nm.

5

Sharp Upper Bounds on the Clar Number of Fullerene Graphs

80%

Gao Y. , Zhang H.

Discussiones Mathematicae Graph Theory

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2017

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tom 38

|

nr 1

155-163

EN

The Clar number of a fullerene graph with n vertices is bounded above by ⌊n/6⌋ − 2 and this bound has been improved to ⌊n/6⌋ − 3 when n is congruent to 2 modulo 6. We can construct at least one fullerene graph attaining the upper bounds for every even number of vertices n ≥ 20 except n = 22 and n = 30.

6

Morphological, topographical and FTIR characterizations of Pd–C films

80%

Rymarczyk J. , Kamińska A. , Kęczkowska J. , Kozłowski M. , Czerwosz E.

Optica Applicata

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2013

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tom Vol. 43, nr 1

123--132

EN

The structure, topography and morphology of Pd–C films were studied by AFM (atomic force microscopy), SEM (scanning electron microscopy), Raman and FTIR (Fourier transform infrared spectroscopy) methods. It was found that an increasing content of palladium in films causes a decrease in their roughness and size of nanograins. The topography and morphology of Pd–C films depend on the content of palladium in the film, what was found from the analysis of SEM and AFM images. FTIR and Raman spectra show that the content of fullerene and palladium in the film strongly depends on technological parameters of PVD (physical vapor deposition) process.

7

Charge-Transfer in Fullerene Complexes

80%

Graja A.

Polish Journal of Chemistry

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2002

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tom Vol. 76 / nr 2-3

167-176

EN

Spectral investigations of fullerene charge-transfer complexes with planar and spatial electron-donor molecules are reported. The results of this study indicate that the CT complexes of C60 with planar donors are involved in polarization interactions of van der Waals type. CT is very weak in these compounds and is hindered by unfavourable steric factors. As a result, the CT rate does not correlate with the ionization potential of the donor. Contrary to the planar donors, the spatial ones form complexes with CT rate approaching 1.

8

Raman studies of Pd-C nanocomposites

80%

Belka R. , Suchanska M. , Czerwosz E. , Keczkowska J.

Open Physics

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2013

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tom 11

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nr 2

245-250

EN

The results of studying palladium-carbon (Pd-C) nanocomposites using Raman spectroscopy are presented. This method has been used for studying samples having various palladium content, prepared by a one-step Physical Vapour Deposition (PVD) process and a Chemical Vapour Deposition (two-step PVD/CVD) process using different process parameters. For samples obtained by PVD, the vibration bands characteristic of C60 fullerene molecules were observed in the spectra, whereas for layers obtained by PVD/CVD, the Raman spectra displayed mainly D and G bands characteristic solely of the prescence of graphite-like layers’ vibrations. The analysis of the obtained Raman spectra reveals that its shape is affected by many parameters including type of substrate, temperature, and the percentage content of Pd in the studied layer. The quantitative analysis of spectra for layers obtained using the PVD/CVD process shows a difference in the relative intensity of bands D and G, reflecting the different degrees of amorphisation in the investigated nanocomposites.

9

Hyperspectral imaging of polymer/fullerene blends

70%

Torreggiani A. , Tinti F. , Savoini A. , Melchiorre M. , Po R. , Camaioni N.

Organic Photonics and Photovoltaics

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2014

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tom 2

|

nr 1

EN

The effectiveness of a hyperspectral imaging system integrated on an enhanced dark-field microscope for probing the microscale morphology of model poly(3- hexylthiopene): [6,6]-phenyl-C61- butyric acid methyl ester (P3HT:PCBM) blends is demonstrated. This non-contact technique provides both spectral and spatial information in one measurement, providing an effective mapping of the presence and location of the component materials in the investigated P3HT:PCBM blends spincoated over different substrates (zinc oxide, poly(3,4- ethylenedioxythiophene):poly(styrenesulfonate). The hyperspectral analysis accounts for the micro-scale morphology of P3HT:PCBM blends, even in case of high film roughness, and the quantitative determination of blend components reveals a preferential accumulation of the lowenergy material (P3HT) at the interface with air, confirming the findings reported with other mapping techniques

10

Spectral studies of some C-60 complexes with TTF-derived donors

70%

Graja A. , Tanatar M. A. , Li Y. L. , Zhu D. B.

Polish Journal of Chemistry

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1998

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tom Vol. 72, nr 5

869-876

EN

Electronic and vibrational spectroscopies were applied to the study of the strength of the donor-acceptor interaction and optical properties of the complexes of C-60 with two TTF-derived donors, i.e. bis(methylthio)ethylenedithio-tetrathiafulvalene (C-1TET- TTF) and tetramethyltetraselenafulvalene (TMTSF). The investigations of the single crystalline samples, for various light polarizations and temperatures, were performed. The analysis of all the spectral data shows that the investigated compounds are weak complexes with a neutral ground state.

11

Fullerene layers between graphite walls - A computer simulation

70%

Skrzypek M. , Gburski Z.

Materials Science Poland

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2005

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tom Vol. 23, No. 2

453--456

EN

The properties of ultra thin fullerene layers located between graphite planes have been studied using the molecular dynamics ( MD) technique. In this arrangement, there is competition between the fullerene - fullerene and fullerene - graphite wall interaction potentials - both potentials being very strong. It appears that the confined fullerenes form two ultra thin layers, parallel to the graphite planes. The mean square displacement, velocity autocorrelation function and Lindemann index of fullerene molecule have been calculated for several temperatures and a range of distances between the graphite walls.

12

Complete Assignment of All 13C NMR Signals of Cs Symmetric Monoazafullerene Derivatives by Comparison of Experimental and Calculated Spectra

70%

Hauke F. , Chen Z. , Hirsch A.

Polish Journal of Chemistry

|

2007

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tom Vol. 81, nr 5-6

971-983

EN

The complete assignment of all 31 13C NMRsignals which are due to the fullerene carbon atoms of monoazafullerene derivatives has been carried out for the first time by the systematic comparison of experimental and theoretical spectra calculated by high level DFT methods (GIAO-B3LYP/6-31G*/B3LYP/6-31G*). The assignment is facilitated by the striking similarities of the signal patterns of the sp2-fullerene carbon atoms of two different families of such heterofullerene derivatives with both aryl and alkyl addends.

13

Photoinduced piezoelectric and elastic effects in the 2-cyclooctylamino-5-nitropyridine–C70 complexes

70%

Kamanina N. V. , Owsik J. , Rusek B.

Optica Applicata

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2013

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tom Vol. 43, nr 3

463--469

EN

We have observed the piezoelectric and elastooptic effects for the 2-cyclooctylamino-5-nitropyridine complex, chromophore doped by an inter-molecular acceptor – fullerene C70. The discovered features may be used for optically operated piezoelectric triggers, modulators and deflectors. The observed effects are caused by the effective interaction of external light with the polarizable chromophore. As a pumping laser beam we have used both a nanosecond fundamental 1064 nm laser wavelength as well as its second harmonic generation at 532 nm. A principal role in the observed effects play photoinduced anharmonic phonons, effectively contributing to the output effect.

14

Structural characterization of room-temperature synthesized fullerene nanowhiskers

60%

Miyazawa K. , Minato J. , Mashino T. , Nakamura S. , Fujino M. , Suga T.

Nukleonika

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2006

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tom Vol. 51,suppl.1

41-48

EN

Structural properties of various kinds of room-temperature synthesized C60 fullerene nanowhiskers were investigated by TEM and XRD. The C60 nanowhiskers prepared by use of toluene lost their initial solvated hexagonal structure faster than the C60 nanowhiskers prepared by use of m-xylene. The hexagonal structure of C60 nanowhiskers prepared by use of toluene was stabilized by adding C60[C(COOC2H5)2]. These results suggest that large solute molecules in the C60 nanowhisker matrix stabilize their initially solvated hexagonal structure. Furthermore, the addition of a sufficient amount of C60(2-methoxycarbonyl-N-methylpyrrolidine) into the m-xylene solution of C60 produced the C60 nanowhiskers indicating the formation of ordered solid solution of C60 and C60(2-methoxycarbonyl-N-methylpyrrolidine).

15

Miniaturized sample preparation based on carbon nanostructures

60%

Cárdenas S.

Sample Preparation

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2014

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tom 2

|

nr 1

EN

The evolution of analytical methodologies has been driven by the objective to reduce the complexity of sample treatment while increasing the efficiency of the overall analytical process. For this reason, the analytical chemist takes into consideration advances in other scientific areas and systematically evaluates the potential influence that such discoveries might have on its own discipline. This is the present situation with nanostructured materials, which have already been recognized as a revolution in many scientific and technological fields, including analytical chemistry. Carbon nanoparticles have been a cornerstone in the advance of miniaturization of analytical processes. This review article considers the contribution of four reference carbon nanoparticles: nanotubes, graphene, nanohorns/ cones and fullerenes, in the context of miniaturized sample treatment, where their outstanding sorbent properties are by far the most exploited in (micro) solid phase extraction.

16

Electrochemical Formation of Two-component Films from 2'-Ferrocenylpyrrolidino[3',4' ; 1,2][C60]fullerene and Transition Metal Complexes

60%

Płońska M. , Makar A. , Winkler K. , Balch A.

Polish Journal of Chemistry

|

2004

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tom Vol. 78 / nr 9

1431-1447

EN

Redox active films have been generated electrochemically by reduction of the chemically modified fullerene, 2_-ferrocenyl-pyrrolidino[3_,4_;1,2][C60]fullerene - FcC60, and [Pt(_-Cl)Cl(C2H4)]2 or Ir(CO)2Cl(p-toluidine). The film is believed to consist of polymeric network formedvia covalent bonds between the metal atoms and the fullerene moieties. Ferrocene is covalently linked to the polymeric chains through the pyrrolidine rings. The FcC60/Pt film is electrochemically active in both positive and negative potential ranges. At positive potentials, oxidation of the appended ferrocene is observed. In the negative potential range, electron transfer processes involving the fullerene take place. FcC60/Pt films exhibit higher permeability to anions than to cations. Only an outermost layer of this film is reduced. During the oxidation of the film significant structural changes occur. Film formation is also accompanied by platinum deposition. The present of a metallic phase in the film influences its morphology, structure and electrochemical properties. An FcC60/Ir film has been formed during reduction of solutions containing both FcC60 and Ir(CO)2Cl(p-toluidine). The yield of this film is low with only very thin layer deposited on the electrode surface. No electrochemical activity of the electrode modified with FcC60/Ir was detected in acetonitrile containing only supporting electrolyte.

17

Dopasowanie modeli do krzywej transmisji rozpuszczania fulerenów w oleju transformatorowym

60%

Kalus P.

Zeszyty Naukowe. Elektryka / Politechnika Opolska

|

2012

|

tom z. 67

25-28

EN

The article presents a description of the selected models of dissolution. Describes the changes made to fit the transmission measurements. Also presents the interpretation of model parameters with respect to the transmission observed during the dissolution of fullerenes in transformer oil.

18

The evaluation of organic solar cell’s properties based on polymer F8BT and fullerene derivative C60PCBM

51%

Bernacki Ł. , Lisik Z. , Łuszczyńska B.

Przegląd Elektrotechniczny

|

2015

|

tom R. 91, nr 9

13-15

EN

The paper included fabrication and characterization of the bulk heterojunction organic solar cell (BHJ OSC) based on poly[(9,9-di-noctylfluorenyl- 2,7-diyl)-alt-(benzo[2,1,3]thiadiazol-4,8-diyl)] (F8BT) and fullerene derivative [6,6]-phenyl-C61-butyric acid methyl ester (C60PCBM). It was studied the influence of annealing the temperature range: 120°C-200°C on absorption properties of F8BT, C60PCBM and F8BT:C60PCBM films. The annealing of films and the encapsulation of OSC’s was carried out under nitrogen atmosphere in glove boxes. Fabricated devices were examined in terms of basic operational parameters such as: open circuit voltage, short circuit current, fill factor, power conversion efficiency. Annealing process at 120°C resulted in power conversion efficiency about 0.053% and fill factor ratio about 31%. Encapsulation after fabrication improved the work parameters of the OSCs and extended their lifetime in relation to non-encapsulation devices.

PL

W ramach prac wytworzono i scharakteryzowano objętościowe heterozłączowe polimerowe, ogniwo fotowoltaiczne (OPV) oparte na poli [(9,9-di-n – oktylofluoren l2,7 - diylu) - alt - (benzo [2,1,3] tiadiazolo-4,8 - diylu)] (F8BT) oraz pochodną fulerenu [6,6] - fenylo - C61 - estru metylowego kwasu masłowego (C60PCBM). Zbadano wpływ wygrzewania warstw F8BT, C60PCBM oraz blendy F8BT:C60PCBM w zakresie od 120°C do 200°C na właściwości absorpcyjne. Wygrzewanie badanych warstw oraz hermetyzację OSC wykonywano w atmosferze azotu w komorach rękawicowych. Dla skonstruowanych urządzeń wyznaczono charakterystyki prądowo-napięciowe oraz podstawowe parametry użytkowe: napięcie obwodu otwartego, prąd obwodu zamkniętego, współczynnik wypełnienia oraz sprawność. Dla fotoogniw wygrzewanych w 120°C uzyskano najwyższą sprawność wynoszącą 0,053% przy współczynniku wypełnienia równym 0,31%. Hermetyzacja po procesie wytwarzania spowodowała poprawę parametrów roboczych urządzeń oraz przedłużyła ich czas życia w stosunku do urządzeń niehermetyzowanych.

19

Widma absorpcji transformatorowych olejów izolacyjnych modyfikowanych fulerenami

51%

Zmarzły D. , Kalus P.

Przegląd Elektrotechniczny

|

2010

|

tom R. 86, nr 11b

33-35

PL

W artykule przedstawiono problem pomiaru stopnia rozpuszczenia fulerenów C60 w izolacyjnym oleju transformatorowym. Przedstawiono w nim widma transmisji olejów dla różnych stężeń fulerenów w oleju transformatorowym. Wskazano również wybór optymalnej długości promieniowania dla pomiarów transmisji. Na tej podstawie została zbudowana mieszarka magnetyczna, w której dokonuje się na bieżąco pomiaru transmisji podczas mieszania.

EN

The article presents the problem of measuring the degree of dissolution of fullerenes C60 in the transformer insulating oil. It presents the transmission spectra for different concentration of fullerenes in the transformer oil. It also identifies the optimal choice of radiation length for transmission measures.

20

Elektryzacja toluenu domieszkowanego fullerenami

51%

Aksamit P.

Zeszyty Naukowe. Elektryka / Politechnika Opolska

|

2008

|

tom Vol. 326, z. 61

7-8

EN

The paper presents the concept of reducing tendency to electrification of toluene by doping with C60 fullerene. The influence of C60 addition on streaming electrification current of toluene was measured using rotating electrometer.