Wyniki wyszukiwania - Biblioteka Nauki

1

Studies on the Electrical Behaviour and Removal of Toluene with a Dielectric Barrier Discharge

100%

Schmidt M. , Schiorlin M. , Brandenburg R.

Open Chemistry

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2015

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tom 13

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nr 1

EN

This contribution attempts to establish an easy-to-apply non-thermal plasma reactor for efficient toluene removal. Derived from the already established knowledge of the so called Dielectric Barrier Discharge (DBD) Stack Reactor a new model reactor was used in this work. The DBD Stack Reactor is a multi-elements reactor but in this work only one stack element was used to investigate the efficiency and efficacy of toluene removal. In case of reliable results the scalability process for industrial application is already well known. Therefore, laboratory experiments were conducted in dry and wet synthetic air with an admixture of 50 ppm toluene. Along with the toluene removal process the electrical behaviour of the discharge configuration was investigated. It was found that the electrical capacitance of the dielectric barrier changes with variations of the operating voltage. This could be due to the changes in the area of the dielectric barrier which is covered with plasma. Additionally, it was found that the power input into the plasma, at a fixed operating voltage, is proportional to the frequency, which is in agreement with the literature. Regarding the decomposition process, the total removal of toluene was achieved at specific input energy densities of 55 J L-1 under dry conditions and 110 J L-1 under wet conditions. The toluene removal was accompanied by the production of nitric acid (dry conditions) and formic acid (wet conditions). The latter suggested a combination of the plasma reactor with a water scrubber as an approach for total removal of pollutant molecules.

2

Study of density of interface states in MOS structure with ultrathin NAOS oxide

88%

Jurečka S. , Kobayashi H. , Kim W.-B. , Takahashi M. , Pinčík E.

Open Physics

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2012

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tom 10

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nr 1

210-217

EN

The quality of the interface region in a semiconductor device and the density of interface states (DOS) play important roles and become critical for the quality of the whole device containing ultrathin oxide films. In the present study the metal-oxide-semiconductor (MOS) structures with ultrathin SiO2 layer were prepared on Si(100) substrates by using a low temperature nitric acid oxidation of silicon (NAOS) method. Carrier confinement in the structure produces the space quantization effect important for localization of carriers in the structure and determination of the capacitance. We determined the DOS by using the theoretical capacitance of the MOS structure computed by the quantum mechanical approach. The development of the density of SiO2/Si interface states was analyzed by theoretical modeling of the C-V curves, based on the superposition of theoretical capacitance without interface states and additional capacitance corresponding to the charges trapped by the interface states. The development of the DOS distribution with the passivation procedures can be determined by this method.

3

Capacitance in microfluidics

88%

Tesar V. , Peszyński K.

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2006

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tom nr 2

29-31

EN

The present article is an introduction to a discussion, in sc veral parts, on the effect of fluid accumulation in devices. In fluidic circuits, this effect has a role analogous to electric capacitance. The basic mechanisms are, however, widely different and it may be interesting to see to what degree this difference influences the resultant relation.

PL

Podczas projektowania i analiz obwodów mikrostrumieniowych, wykorzystywane są szeroko ich odniesienia do elementów i obwodów elektronicznych. Jednakże elementy mikrostrumieniowe mają swoje własne specyficzne własności. Prezentowany artykuł jest wprowadzeniem do analizy, w kilku częściach, dotyczącej akumulacji płynu w urządzeniach. W elementach strumieniowych rola tego zjawiska jest podobna do zjawiska reaktancji pojemnościowej.

4

Self and mutual capacitance of conductors in air and lossy earth with application to electrified railways

75%

Mariscotti A.

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nr 4

5

Ac electrical parameters of Al-ZnPc-Al organic semiconducting films

63%

Kitaneh R. , Saleh A. , Gould R.

Open Physics

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2006

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tom 4

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nr 1

87-104

EN

The ac electrical parameters of thermally evaporated zinc phthalocyanine, ZnPc, semiconducting thin films was measured in the temperature range of 180–390 K and frequency between 0.1 and 20 kHz. Aluminum electrode contacts were utilized to sandwich the organic ZnPc semiconducting films. Capacitance and loss tangent decreased rapidly with frequency at high temperatures, but at lower temperatures a weak variation is observed. An equivalent circuit model assuming ohmic contacts could qualitatively and successfully explains capacitance and loss tangent behavior. The ac conductivity showed strong dependence on both temperature and frequency depending on the relevant temperature and frequency range under consideration. Ac conductivity σ (ω) is found to vary with ω, as ω s with the index s ≤ 1.35 suggesting a dominant hopping conduction process at low temperatures (< 250 K) and high frequency. The conductivity of some samples did not increase monotonically with temperature. This behavior was attributed to oxygen exhaustion of the sample as its temperature is increased. The ac conductivity behavior at low temperatures of ZnPc films could be described well by Elliott model assuming hopping of charge carriers between localized sites.

6

Bezkontaktowy pomiar zmian grubości polimerów elektroaktywnych pobudzanych wysokonapięciowo

63%

Malinowski M. , Żyłka P.

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2008

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tom R. 84, nr 10

90-93

PL

Elastomerowe elektrostatyczne aktuatory dielektryczne (DEA) charakteryzują się niskim modułem sprężystości, co w praktyce doświadczalnej utrudnia prawidłowe przeprowadzenie pomiarów odkształceń próbek tych materiałów, wywołanych pobudzeniem wysokonapięciowym. Praca omawia metodę bezkontaktowego pomiaru zmian grubości tego typu materiałów w obecności pola elektrycznego o dużym natężeniu poprzez rejestrację niewielkich zmian pojemności elektrody na próbce względem elektrody odniesienia.

EN

Low value of the elastic constant of elastomeric Dielectric Electrostatic Actuators (DEA) makes it difficult to directly measure their thickness displacement, induced by high-voltage excitation. The paper presents a new approach to contactless measurement of DEA thickness change in existence of a strong, interfering electric field. The presented method relays on registering subtle changes in capacitance of the sample electrode-reference electrode system.

7

Rare earth oxide films: their preparation and characterization

44%

Wiktorczyk T.

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tom Vol. 31, nr 1

5-33

EN

Summarises the results of our investigations dealing with preparation of rare earth oxide films and examinations of their physical properties. Different deposition methods have been applied for fabrication of these films and rare-earth-oxide-based thin film coatings. The main results concerning film microstructure and optical properties in the wavelength range from the UV up to the IR are presented. Electrical and dielectric studies have been carried out in the time domain and in the frequency domain (from very low frequencies up to radio frequencies) for selected rare earth oxides. MIM sandwich-type structures have been fabricated for this aim. Trapping levels in these oxides have been investigated. The complex impedance diagnostics was applied to the analysis of the volume of the R/sub 2/O/sub 3/ film and interfacial properties (metal/insulator barriers) of M/R/sub 2/O/sub 3//M thin film structures.

8

Właściwości dynamiczne linii hydraulicznych lotniczych napędów hydraulicznych

38%

Ułanowicz L.

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2008

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tom nr 23

89-116

PL

W artykule zaprezentowano wyniki analiz własności dynamicznych linii hydraulicznej uwzględniających efekt bezwładności cieczy płynącej w przewodzie sztywnym, jak i gięt-kim, efekt ściśliwości tej cieczy i efekt tarcia lepkiego. W rozważaniach potraktowano linię hydrauliczną jako czwórnik o dwóch wejściach i dwóch wyjściach, charakteryzujący się określoną macierzą transmitancji. Główne rozważania przeprowadzono dla modelu o zmiennej rezystancji. Podano rozwiązanie ogólne w funkcji operatora Laplace'a oraz adaptację modelu linii hydraulicznej dla przepływu turbulentnego i przepływu przez przewód o sprężystych ściankach. Wprowadzając odpowiednie uproszczenia do modelu o zmiennej rezystancji otrzymano kolejno model o stałej rezystancji i model linii bez strat.

EN

This paper presents the results of a hydraulic line dynamic properties analysis taking into account inertia of the fluid flowing in rigid and flexible lines, the compressibility effect for this fluid and the viscous friction effect. The following are described and analyzed: solution of the wave equation in the form binding four variables: pressure and flow rate at the line input, and pressure and flow rate and the line output; two of the above-mentioned variables should be regarded as independent (input) and the other two as dependent (output), the accuracy comparison of distributed parameters model to lumped parameters model with regard to applicability range in hydraulic systems analysis, pressure value at given installa-tion points as a response to rapid valve closing (transient response) or to valve opening (fluid hammer effect). In these considerations the hydraulic line is regarded as a two-port with two inputs and two outputs with a definite transmittance matrix. Main considerations concern the variable resistance model. A general solution is given as a function of the Laplace operator. Adaptation of the hydraulic line model to the turbulent flow and to the flow through a line with elastic boundaries is given. Introducing appropriate simplifications into the variable resistance model, the constant resistance model and lossless line model is obtained. Also, general solutions for three different lump parameter models are presented. Accuracy of individual methods are compared with examples for selected systems.