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1

Carbon nanotubes functionalized by salts containing stereogenic heteroatoms as electrodes in their battery cells

Zdanowska S., Pyzalska M., Drabowicz J., Kulawik D., Pavlyuk V., Girek T., Ciesielski W.

Polish Journal of Chemical Technology

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2016

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Vol. 18, nr 4

22--26

EN

This paper concentrates on electrochemical properties of groups of multi-walled carbon nanotubes (MWCNT) functionalized with substituents containing a stereogenic heteroatom bonded covalently to the surface of the carbon nanotube. This system was tested in Swagelok-type cells. The cells comprised a system (functionalized CNT with salts containing S and P atoms) with a working electrode, microfiber separators soaked with electrolyte solution, and a lithium foil counter/reference (commercial LiCoO2 ) electrode. The electrolyte solution was 1 M LiPF6 in propylene carbonate. Using standard techniques (cyclic voltammetry/chronopotentiometry), galvanostatic cycling was performed on the cells at room temperature with a CH Instruments Model 600E potentiostat/galvanostat electrochemical measurements. Methods of functionalization CNT were compared in terms of the electrochemical properties of the studied systems. In all systems, the process of charge/discharge was observed.

2

Badanie procesu transferu ładunku wzbudzanego światłem w organicznych ogniwach słonecznych za pomocą czasowo rozdzielczej fotoluminescencji i pobudzanego światłem elektronowego rezonansu spinowego

Grankowska-Ciechanowicz S., Iwan A., Wołoś A., Korona K. P., Kamińska M.

Prace Instytutu Elektrotechniki

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2014

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Z. 264

65-71

PL

Organiczne ogniwa słoneczne są jednym z obiecujących sposobów przetwarzania energii słonecznej w elektryczną. Procesem mającym decydujący wpływ na ich działanie, jest transfer ładunku wzbudzany światłem. Techniki pomiarowe, które znalazły zastosowanie do bezpośredniej detekcji tego procesu, to czasowo rozdzielcza fotoluminescencja (TRPL – ang. time-resolved photoluminescence) i pobudzany światłem elektronowy rezonans spinowy (LESR – ang. light-induced electron spin resonance). Efektywny transfer ładunku, przy pomocy TRPL, rejestrowany jest jako wygaszanie luminescencji w wyniku przestrzennego rozseparowania ładunków przeciwnego znaku, a za pomocą LESR jako dwie linie pochodzące od dodatniego polaronu po stronie donora i ujemnego polarnu po stronie akceptora. W niniejszej pracy omówione zostaną wymienione techniki pomiarowe oraz ich zastosowanie do detekcji efektywnego transferu ładunku w organicznych ogniwach słonecznych.

EN

The organic solar cells are considered as promising way to convert solar energy into electricity. A crucial step in their operations is a photo-induced charge transfer (CT). Techniques, which directly detect this phenomenon, are Time-Resolved Photoluminescence (TRPL) and Light-induced Electron Spin Resonance (LESR). Effective photo-induced CT results in electrons and holes separation and creation of positive and negative polarons. First process is registered by TRPL as luminescence quenching, second by LESR as two lines, one from positive, and another from negative polarons. In this article, both techniques will be described as well their application in effective CT detection.

3

Green synthesis and characterization of cuprous oxide nanoparticles in presence of a bio-surfactant

Behera M, Giri G

Materials Science Poland

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2014

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Vol. 32, No. 4

702--708

EN

Herein, we report a facile green synthesis of Cu2O nanoparticles (NPs) using copper sulfate as precursor salt and hydrazine hydrate as reducing agent in presence of bio-surfactant (i.e. leaves extract of arka – a perennial shrub) at 60 to 70 °C in an aqueous medium. A broad band centered at 460 nm in absorption spectrum reveals the formation of surfactant stabilized Cu2O NPs. X-ray diffraction pattern of the surfactant stabilized NPs suggests the formation of only Cu2O phase in assistance of a bio-surfactant with the crystallite size of ∼8 nm. A negative zeta potential of −12 mV at 8.0 pH in surfactant stabilized Cu2O NPs hints non-bonding electron transfer from O-atom of saponin to the surface of NP. Red-shift in the vibrational band (Cu–O stretching) of Cu2O from 637 cm−1to 640 cm−1 in presence of bio-surfactant suggests an interfacial interaction between NPs and O-atoms of –OH groups of saponin present in the plant (i.e. Calotropis gigantea) extract. From X-ray photoelectron spectroscopy spectra, a decrease in binding energy of both 2p3/2and 2p1/2 bands in Cu2O with saponin molecules as compared to bulk Cu atom reveals a charge transfer interaction between NP and saponin surfactant molecules. Transmission electron microscopy images show crystalline nature of Cu2O NPs with an fcc lattice.

4

Zastosowanie metody transferu ładunku do budowy interfejsu użytkownika urządzeń EAZ

Kalinowski A., Kowalski G.

Elektronika : konstrukcje, technologie, zastosowania

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2014

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Vol. 55, nr 7

88-89

PL

W artykule opisano metodę transferu ładunku. Przedstawiono funkcje interfejsu użytkownika urządzeń EAZ i badania modelu interfejsu.

EN

The article describes a method for the charge transfer. The paper presents functionality of the user interface devices EAZ and test of design.

5

Chemia kwantowa w molekularnej optyce nieliniowej

Wielgus M., Kozłowska J., Bartkowiak W.

Wiadomości Chemiczne

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2012

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[Z] 66, 1-2

1-18

EN

We review quantum-chemical methodologies based on simple two- and three- state models for molecular hyperpolarizabilities and two-photon cross-sections. In this article we show that simplified few-state models, obtained from sum -over-states formalism, are important tools for investigations structure-property relationships for various type of đ-conjugated compounds. These relationships are important for rational design of molecules with large nonlinear optical response

6

Influence of sol-gel matrices on the optical excitation of europium ions

Banski M., Podhorodecki A., Misiewicz J.

Materials Science Poland

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2010

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Vol. 28, No. 1

217--227

EN

Photoluminescence (PL), total photoluminescence excitation (TPLE), transmission and decay photoluminescence experiments were done to establish the most efficient excitation mechanism of the europium (Eu3+) ions in amorphous Al2O3 and Y3Al5O12 host matrices. Both matrices were fabricated using the sol-gel technique, doped with Eu3+ ions and sputtered on a flat quartz plate. Because of relatively low temperatures of annealing (200 °C), after this treatment the matrices should remain in an amorphous phase. In such a system, Eu3+ ions occupy the points having different site symmetries. However, based on characteristic features of the PL spectra, the effective site symmetry (ESS) parameter was defined to describe the PL properties of the Eu3+ ions in various matrices. Low intensive direct f-f transitions at 392, 465, 530 nm were observed in the TPLE spectra. The most intensive, wide excitation bands were centred at around 250-260 nm and the charge transfer process was found to be related to these excitation bands. Finally, a good correlation between photoluminescence lifetimes, the PL intensity and CT energy was observed.

7

Dehydration-Induced Charge Transfer in Ni3[Fe(CN)6]2ź15H2Oe T

Liu M., Bian X. F., Xia Y. F., Bao Z., Xu M. X.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 10

1729-1735

EN

Molecular magnet nickel(II) hexacyanoferrate(III), powder Ni3[Fe(CN)6]2ź15H2O, was prepared by coprecipitation method. The coprecipitated powder was annealed in vacuum at different temperatures of 80, 100, 120, and 140 graduate C. Water molecules contained in Prussian blue analogues were removed by heating. The effects of dehydration on its charge transfer properties were studied by Fourier-transform infrared and Mössbauer measurements. It was found that the FeIII–CN–NiII state is the major structure in the coprecipitated form, while the FeII–CN–NiIII bond is formed in the annealed samples. The dehydration of NiII ferricyanide above 80°C induces an inner charge transfer from NiII towards FeIII to form the mixed valence system Ni(II) Ni(III) ferri-ferro-cyanide.

8

Multi-Pulse Excitation Reveals a Novel Excited State Pathway in a Peryleneimide-Pentaphenylene Dyad

Fron F., Schweitzer G., Jacob J., Müllen K., Van der Auweraer M.

Polish Journal of Chemistry

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2008

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Vol. 82, nr 4

701-713

EN

The excited state properties of a peryleneimide-pentaphenylenedyad were in vestigated in detail using pump-probe, single photon timing and three-beam pulsed experiments. Upon excitation with 395 nm pulses ultrafast energy transfer was found to occur from the pentaphenylene to the perylene subunit. In polar solvents this excitation energy transfer is followed by charge transfer from the electron donor pentaphenylene to the electron acceptor perylene. A three-beam femtosecond transient absorption technique revealed the relaxation dynamics of a higher lying singlet state of the peryleneimide subunit to occur on a picoseconds time scale. These results demonstrate the potential use of the threebeam femtosecond technique in manipulating excited states processes.

9

Spectrophotometric determination of lisinopril in commercial dosage forms using N-bromosuccinimide and chloranil

Rahman N., Siddiqui M. R., Azmi S. N. H.

Chemia Analityczna

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2007

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Vol. 52, No. 3

465-480

EN

Two simple, fast, sensitive, and economical spectrophotometric methods for quantification of lisinopril in drug formulations have been developed. Method A was based on the reaction between primary amino group of the drug with N-bromosuccinimide in acetone medium giving a yellow-colored product of maximum absorption at 353 nm. Method B was based on the formation of purple-colored charge transfer complex between the drug and chloranil in 1,4-dioxan-acetonitriIe medium. Beer's law was obeyed in the concentration ranges of 10-200 and 24-600 μg mLTwo simple, fast, sensitive, and economical spectrophotometric methods for quantification of lisinopril in drug formulations have been developed. Method A was based on the reaction between primary amino group of the drug with N-bromosuccinimide in acetone medium giving a yellow-colored product of maximum absorption at 353 nm. Method B was based on the formation of purple-colored charge transfer complex between the drug and chloranil in 1,4-dioxan-acetonitriIe medium. Beer's law was obeyed in the concentration ranges of 10-200 and 24-600 ug mL'1 with molar absorptivities of 1.40 x 103 and 7.28 x 102 L-1 mol cm'1 for methods A and B, respectively. Regression analysis yielded the following calibration equations: A = -2.44 x 10-1 + 3.16 x 10-1 C and A = 5.39 x 10-4+ 1.65 x 10-3C for methods A and B, respectively. For both calibration equations correlation coefficients were 0.9999. Intra- and inter-day precisions were lower than 1.60%. The optimum experimental conditions for the proposed methods have been investigated. Methods A and B have been successfully applied to the analysis of lisinopril in drug formulations. The results have been statistically compared to these obtained applying the British pharmacopoeia method with molar absorptivities of 1.40 x 103 and 7.28 x 102 L-1 mol cm-1 for methods A and B, respectively. Regression analysis yielded the following calibration equations: A = -2.44 x 10-1 + 3.16 x 10-1 C and A = 5.39 x 10-4+ 1.65 x 10-3C for methods A and B, respectively. For both calibration equations correlation coefficients were 0.9999. Intra- and inter-day precisions were lower than 1.60%. The optimum experimental conditions for the proposed methods have been investigated. Methods A and B have been successfully applied to the analysis of lisinopril in drug formulations. The results have been statistically compared to these obtained applying the British pharmacopoeia method

PL

Opracowano dwie proste, szybkie, czule i ekonomiczne spektrofotometryczne metody ilościowego oznaczania lizynoprilu w preparatach farmaceutycznych. Metoda A jest oparta na reakcji picrwszorzędowej grupy aminowej leku z N-bromosukcynimidem w acetonie, w wyniku której powstaje żółty produkt wykazujący maksimum absorpcji przy df. fali 353 nm. Metoda B polega na tworzeniu purpurowego kompleksu z przeniesieniem iadunku miedzy lekiem a chloranilem w mieszaninie 1,4-dioksanu i acetonu. Prawo Beer'a było . spełnione w zakresie stężeń 10-200 i 24-600 1.40 x 103; absorpcja molowa wynosiła 1.40 x 103 and 7.28 x 102 L-1 mol cm-1, odpowiednio w przypadku metody A i B, W wyniku analizy regresji otrzymano dwa równania kalibracyjne A =-2,44 x 10-4 + 3,16 x 10-3 C oraz A = 5,39 x10-4 + 1,65 x 10-3 C, odpowiednio dla metody A i B. Obie metody zoptymalizowano i zastosowano z powodzeniem do analizy lizynoprilu w preparatach farmaceutycznych. Otrzymane wyniki porównano z wynikami uzyskanymi według Farmakopei Brytyjskiej.

10

The temporal dipole moments of solute molecules undergoing charge transfer

Krzysztofowicz A, Tomin V I

Optica Applicata

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2006

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Vol. 36, nr 4

s. 483--487

EN

The expression for time dependence of excited state dipole moment of molecule with charge transfer on the correlation function of instant spectra kinetics has been deduced on the basis of the theory of solvatochromism. Time dependence of excited state dipole moment of well known luminescence probe 6-propionyl-2-dimethylaminonaphtalene in polar solvent is presented.

11

Molecular impurity ions as centres with charge transfer degrees of freedom. Influence on ferroelectric phase transitions.

Vikhnin V. S., Maksimowa T. I., Hanuza J.

Materials Science Poland

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2005

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Vol. 23, No. 3

677--684

EN

The concept of molecular impurity ions (MI) as centres with charge transfer degrees of freedom, interacting (through the order parameter of the phase transition) with local vibrations and non-soft phonons, as well as with light, has been developed. It has been shown that MI can significantly influence a ferroelectric phase transition (FPT) due to a direct interaction of their specific charge transfer degrees of freedom with the ferroelectric order parameter. In this work, we predict a significant increase of the FPT critical temperature when increasing the MI concentration. The e MnO4- molecular impurity ions embedded in ferroelectric crystals (e.g. molybdates, tungstates, chromates, phosphates) are considered as possible candidates capable of inducing this effect.

12

Some properties of fullerenes and carbon nanotubes

Byszewski P., Klusek Z.

Opto-Electronics Review

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2001

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Vol. 9, No. 2

203-210

EN

Experiments on preparation of C₆₀ONCFn cycloadduct (Fn = ferrocente) and C₆₀(CoCp₂)₃ charge transfer complexes are described and their properties analysed. The ferrocene derivative is bound to C₆₀ at the 6-6 bond by a heterocyclic oxygen-nitrogen-carbon ring. The experimental results are compared with the results of modelling using semiemprical quantum chemistry PM3 model. Scanning tunnelling microscopy and spectroscopy has been used to observe variation of electronic structure along capped carbon nanotubes deposited on freshly cleaved HOPG(0001) surface. The electronic structure has been derived from measured dependence of tunnelling conductance dI/dV on the applied voltage. Evolution of dI/dV(V) along the nanotube are discussed in terms of existing theories of nanotubes and quantum chemistry calculations.

13

Silica modified by ß-iminoketonate groups as stationary phase for complexation gas chromatography

Rykowska I., Wasiak W.

Chemia Analityczna

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2001

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Vol. 46, No. 4

489-499

EN

Complexes of Cu(II) chemically bonded to silica surface via iminoketonate groups were studied towards their use in gas chromatography. The packing was investigated to evaluate its usefulness in the analysis of aliphatic and aromatic hydrocarbons. A number of retention parameters was determined (retention factor — k, retention index — I, specific retention volume - Vg molecular retention index — ^Me), which enabled to characterize specific interactions between bonded metal and adsorbate molecules. A packing containing no bonded metal was also investigated and treated as reference. The physical and chemical properties of the packings were determined as well as possibilities of analytic use of the packings under study were presented.

PL

Prezentowana praca dotyczy wykorzystania w chromatografii gazowej chemicznie związanych z powierzchnią krzemionki, przez grupę ketoiminową, kompleksów miedzi. Otrzymane wypełnienie poddano badaniom mającym na celu określenie jego przydatności w analizie alifatycznych i aromatycznych węglowodorów. Wyznaczono parametry retencyjne (współczynnik retencji k, indeks retencji I, właściwa objętość retencji Vf, molekularny indeks retencji AMC), pozwalające na charakterystykę oddziaływań specyficznych związanego metalu z cząsteczkami adsorbatów. Pomiary przeprowadzono także dla wypełnienia bez związanego metalu, traktujące je jako referencyjne. Wypełnienia poddano również badaniom określającym ich właściwości fizykochemiczne oraz zademonstrowano możliwości analitycznego wykorzystania badanych faz stacjonarnych.

14

Design of selective layers for solid state electrochemical gas sensors

Josowicz M.

Chemia Analityczna

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2001

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Vol. 46, No. 2

161-174

EN

Conducting polymers offer a possibility for developing material properties that are critical to the sensitivity, selectivity and fabrication of potentiometric solid state gas sensors. The formation of charge transfer complex between the gaseous species and the semiconducting material results in chemical modulation of the work function of the polymer. Methods of primary doping of the conducting polymers that lead to a stable and adjustable value of the work function will be discussed using polyaniline as an example.

PL

Polimery przewodzące dają możliwość poprawienia tych właściwości materiałów, które decydują o czułości, selektywności oraz mają istotne znaczenie przy preparowaniu potencjometrycznych stałych sensorów na gaz. Tworzenie kompleksów z przeniesieniem ładunku między cząsteczkami gazu i półprzewodzącym materiałem prowadzi do zmian w funkcji pracy polimeru. W pracy przedyskutowano, na przykładzie polianiliny, metody domieszkowania przewodzących polimerów, które umożliwiają regulowanie i stabilizowanie wartości funkcji pracy.

15

Ultrafast electron transfer in tetracyanoethylene-benzene charge transfer complex

Jarzęba W., Tokarczyk B., Murata S., Tachiya M.

Bulletin of the Polish Academy of Sciences. Chemistry

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1999

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Vol. 47, No. 4

347-360

EN

Ultrafast pump-probe transient absorption spectroscopy has been applied to study return electron transfer in the tetracyanoethylene- benzene electron donor-acceptor complex in several polar and non-polar solvents. Ultrafast excitation of the charge transfer band of the complex yields an excited Franck-Condon state, which relaxes to form a contact ion pair. The decay time of the ion pair is, in most cases, longer than the solvation time and is observed on a time scale from 2 picoseconds to 1 ns, depending on the solvent. Using the empirical solvent polarity scale ^vG153 and a conventional non-adiabatic theory of electron transfer, absolute rate constants for the non-radiative return electron transfer can be predicted in different solvents.

16

Real-time probing of elementary charge transfer processes in liquids and solutions

Gauduel Y.

Bulletin of the Polish Academy of Sciences. Chemistry

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1999

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Vol. 47, No. 4

303-331

EN

With the intensive development of ultrafast spectroscopic methods, the course of elementary reactions may be observable on the time scale of molecular motions. The : femtosecond solution chemistry allows the real-time probing of solvent cage effects during charge transfers. Recent studies devoted to the understanding of electron dynamics in : liquid phase are presented and discussed in the framework of quantum theories on nonequilibrium electronic states. This progress provides guidance for further research works on the microscopic description of reactional processes occurring in complicated many body systems.

17

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

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

Polish Journal of Chemistry

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1998

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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.

18

Phase transformations in locally anharmonic systems. Susceptibility approach to orientational instabilities in molecular solids

Kuchta B., Luty T.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 2

426-432

EN

A model of the structural transformation has been discussed, where the local potential is anharmonic but single-welled. Such potential representants a Hamiltonian to model the structural phase transition in charge-transfer molecular crystals A-TCNB (anthracene-tetracyanobenzene). The conditions for the instability and transformation have been found, using the static susceptibility approach, and compared with the variational approximation. The latter method gives a six times lower transition temperature. The fluctuations and entropy are pointed out as the cause of this difference. The exact transition temperature has been calculated by simple Monte Carlo simulations. A comparison with a double-welled case, which models the structural transition in N-TCNB molecular crystal (naphthalene-tetracyanobenzene), has been presented.

19

Matrix infrared spectra of C6H6-HNO3 and C6H6-HONO complexes in solid argon

Krajewska M., Mielke Z.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 2

335-346

EN

Infrared spectra of the complex between C6H6 and HNO3, trans-HONO and cis-HONO in solid argon are reported. Nitric acid and both isomers of nitrous acid form stable 1:1 hydrogen bonded complexex in which the OH group of an acid is interacting with the II-electron system of benzene ring. In addition the nitric acid appears to form another 1:1 complex in which both OH and NO2 group interact directly with the benzene ring. In both benzene-nitric acid and benzene-nitrous acid systems the higher order aggregates (C6H6)nHNO3, (C6H6)nHONOn>2 are easily formed.

20

Kinetics of the reaction of 2,3,5,6-tetrachloro-1,4-benzoquinone with imidazole in acetonitrile and benzene

Dworniczak M., Przybyszewska M., Jarczewski A.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 1

108-112

EN

Nucleophilic vinylic substitution of 2,3,5,6-tetrachloro-1,4-benzoquinone by imidazole in acetonitrile and benzene has been studied spectrophotometrically. The reaction product is the diaminodichlorosubstituted quinone. The values of the activation parameters indicate that there is a considerable charge separation in the transition state. The reaction mechanism is discussed.