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Główne wyniki opracowania RETwix zostały przedstawione w artykule. RETwix jest uniwersalnym sprzętem i oprogramowaniem do badań laboratoryjnych, które można wykorzystać do badania zarówno komponentów elektronicznych, jak i dowolnych procesów elektrycznych, termicznych, chemicznych lub biochemicznych. W tym celu zostały wykorzystane czujniki, aktuatory i przetworniki sygnału Analog Front-End. RETwix zawiera dwa urządzenia CV-LAB (Capacitance & Voltage LABoratory) oraz UA-LAB (Universal Analog LABoratory). Zostały opisane osobliwości budowy oraz przykłady zastosowania RETwix.

In the paper double-channel emission from organic exciplex coupled to fluorescence emission has been shown for the first time. The process has been demonstrated for white emission in light-emitting diodes based on yellow-green organic exciplex combined with organic blue fluorescence emission. Combining the fluorescence emission of mMTDATA with the thermally activated delayed fluorescence exciplex emission from the DPNC/Bphen interface, a highly efficient white OLED has been fabricated. As a result, bright white OLED with a high luminance exceeding 10 000 cd/m2 has been obtained.

The results of studies of the electrically controlled elements of optical systems based on hydrogel - electrochromic polymer with conjugated π-electron system are shown. One important feature of co...

The problem of functional integration of thermal and capacity research methods, which provides the possibility of realizing a new generation of analog front­end of the Internet of Things in the areas of materials science, biophysics and medicine, is solved. Functional integration means the possibility of the use of the same structure for its controlled heating and temperature measurement. For this purpose, instead of discrete resistive heaters and temperature sensors, transistor structures are proposed. This helps to minimize the sizes of measurement transducers, and so the spatial resolution of the transducers­based sensors of thermal analysis. The concept of constructing the functionally integrated thermal sensors based on the transistor structures and capacitive signal transducers is developed. The novelty of the proposed sensors of thermal analysis, in addition to measurement of temperature and amount of thermo­energy emitted and absorbed in the object of research, is the possibility of measuring the electrical capacity. This possibility could be particularly assured by the measurement of temperature deformation of a research object or a console that is bent under the effect of the object. The new solution of the control scheme of the transistor transformers that support the pulse managed heating and forming the informative signal of the temperature of transistor is proposed. The high precision Analog Devices AD7747 24­bit converter is taken as the basis of the capacitive signal transducer. The developed transducer provides the managed heating of research objects and is characterized by the high values of temperature resolution (not worse than 0.01 oC) and electrical capacity (not worse than 10–16 aF) measurement.

A structural and functional block diagram of treatment diagnostic devices on a flexible algorithm has been developed. An algorithm of the system of continuous monitoring as the basis for implementing the new class of devices feature automatic continuous evaluation of effectiveness treatments has been proposed.

CdTe/CdS core-shell quantum dots were synthesized and implemented into a light emitting device resulting in multi-channel electroluminescence with a light-green emission colour. The main electroluminescence band at about 530 nm corresponds to the emission by the CdTe core (type I core/shell structure), while the next emission band at 595 nm is assigned to the crossed recombination of electrons from the conduction band of the CdS shell and holes from the valence band of the CdTe core (type II core/shell structure). At the same time, the photoluminescence spectrum of the synthesized CdTe/CdS core-shell quantum dots contains only one emission band distinctive for type II structures. This behavior of CdTe/CdS core-shell quantum dots upon the electroexcitation allows the extension of the electroluminescence spectrum in the optical region in a way that is useful for the lighting-source applications. Such multi-channel electroluminescence can most probably also be reproduced in related core-shell systems accounting for size-confinement between the core size and shell thickness.

The measuring transducer ensuring three functional properties, such as, formation of an informative signal of induction of the measured field, controlled heating of the magnetotransistor structure with the determination of the heat energy amount released in the structure during heating and temperature measurement of the magnetotransistor structure, was developed. The informative signals of the magnetic field parameters are the differential and summed collector currents of a magnetotransistor whereas the temperature informative signal is the voltage drop on the forward-biased collector p-n-junction in reverse operation mode.

Optic properties of cholesterol liquid crystals promote their use as active elements of optic sensors for quantitative and qualitative evaluation of biological substances. The change of spectral characteristics of cholesterol liquid crystals occurs during contact with biological substances, which is the basis for detection, identification and diagnostics of biological objects. Spectral characteristics of liquid crystal substances based on cholesterol liquid crystal BLO-62 with admixture of nematic liquid crystal 5CB and their change on introduction of aqueous solutions of pepsin and trypsin have been investigated. Concentration of pepsin (6%) and trypsin (10%) in aqueous solutions and their content in liquid crystal medium has been optimized to achieve maximal value of spectral sensitivity coefficient. The optical converter was developed with cholestric liquid crystal as a sensitive element. For the enzymes investigation the structural scheme of the sensor device is developed and the peculiarities of the information signal formation are presented. The sensor operation algorithm is developed to measure different types of enzymes.

For the prediction purpose of patient's individual treatment effectiveness, the pilot research of the Kaplan Meyer method modification was conducted. As selection data the patient's ultrasound examinations of a gall bladder in five years were used. Processing and the analysis of results had been carried out with the Microsoft Azure Machine learning program using of neuronal networks creation. As criterion for improvement of treatment effectiveness served the absent integral indicator of pathological changes.

Research work is devoted to experimental studying of laser technology of receiving inorganic semiconductor oxidic glasses. Approbation more than 50 compositions of glasses is carried out. Stages and processing methods of glass receiving have been considered.

Series of compounds consisting of carbazole arms and 1,3,5-triazine core linked by amino group were synthesized and characterized. The clear relationship between electrochemical properties, quantum efficiency, charge transport properties and structure were estimated. The exciplex-forming properties of the synthesized compound as donor, and two known exciplex-forming acceptors 4,7-diphenyl-1,10-phenanthroline (Bphen) and 2,2′,2"-(1,3,5-benzenetriyl)-tris(1-phenyl-1-H-benzimidazole) (TPBi) where predicted and investigated. It was shown that the star-shaped configuration of the compound 3CzNCprovides the best exciplex OLED performance with EQE up to 6.84%.

The bicarbazole derivative 4,4'-(9H, 9'H-[3,3'-bicarbazole]-9,9'-diyl) bis(3-(trifluoromethyl) benzonitrile), denoted as pCNBCzoCF(3), was synthesized and tested for white OLED applications. pCNBCzoCF3 demonstrated an extremely small value of the singlet-triplet energy gap that caused intensive thermally activated delayed fluorescence (TADF). In addition, this compound is able to form exciplex-type excited states at the interface with star-shaped 4,40,400-tris[phenyl(m-tolyl) amino] triphenylamine (m-MTDATA). Combining the TADF emission of pCNBCzoCF3 with the exciplex emission from the pCNBCzoCF(3) m-MTDATA interface, we fabricated a number of highly efficient "warm-white'' OLEDs, the electroluminescence of which was close to candle emission. The best device demonstrated a very high brightness of 40 900 Cd m(-2) (at 15 V), current efficiency of 53.8 Cd A(-1) and power efficiency of 19.3 lm W-1, while the external quantum efficiency reached 18.8%. The fabricated devices demonstrated high emission characteristics even for the standard test at 1000 Cd m(-2) (current efficiency of 46.2 Cd A(-1), power efficiency of 10.6 lm W-1, EQE of 17.0%). QC 20180223

The star-shaped compound tri(9-hexylcarbazol-3-yl) amine (THCA) and 4,7-diphenyl-1,10-phenanthroline (Bphen) were used for the preparation of bilayer and bulk exciplex based organic light emitting diodes (OLEDs) in which THCA and Bphen were selected as donor and acceptor components, respectively. The dependencies of the electroluminescence and impedance characteristics of the exciplex type OLEDs depending on the technologies of the formation of the active layers were studied. The correlations between the appearance of negative differential resistance in current–voltage characteristics and negative capacitance observed at low frequencies in impedance spectra of OLEDs with the resonant tunneling of electrons into THCA through Bphen/THCA barrier and generation–recombination processes in THCA were established.

A pulse sequence shaper for the pursuance of the research using a wide spectrum of radiospectroscopy and relaxation methods in NQR is proposed. The distinctive feature of this product is its implementation with the application of a multi-functional programmable frequency synthesizer suitable for high-speed amplitude and phase manipulations.

Liquid crystalline materials can be used as an active media for the new generation of planar light guides. The main characteristics which governs light-guiding and switching abilities of such devices are the spatial distributions of the refraction indices (defined via the distribution of nematic director) for the liquid crystal confined within a light-guiding pore. We aim to obtain these distributions from the molecular dynamics simulation of the liquid crystalline cell with the homeotropic boundary conditions being applied. We discuss the reorientation kinetics of the homeotropic-planar transition and obtain the equilibrium director profile upon application of the planar reorienting field.

We fabricated a yellow organic light-emitting diode (OLED) based on the star-shaped donor compound tri(9-hexylcarbazol-3-yl)amine, which provides formation of the interface exciplexes with the iridium(III) bis[4,6-difluorophenyl]-pyridinato-N,C2']picolinate (FIrpic). The exciplex emission is characterized by a broad band and provides a condition to realize the highly effective white OLED. It consists of a combination of the blue phosphorescent emission from the FIrpic complex and a broad efficient delayed fluorescence induced by thermal activation with additional direct phosphorescence from the triplet exciplex formed at the interface. The fabricated exciplex-type device exhibits a high brightness of 38 000 cd/m(2) and a high external quantum efficiency.

A general method for determining the global maximum of the linear electro-optic effect in crystalline materials based on the construction and analysis of extreme surfaces obtained as a result of the optimization procedure is proposed. The electrically induced optical path length changes for ordinary and extraordinary waves as well as the optical path difference for orthogonally polarized waves were used as the objective functions in the optimization. The objective functions were determined for units of the electric field and crystal thickness in the light pass direction. In the example of LiNbO

In the present work we have demonstrated double-channel emission from organic exciplexes coupled to inorganic nanoparticles. The process is demonstrated by yellow-green emission in light-emitting diodes based on organic exciplexes hybridized with perovskite-type dispersed BaZrO3 nanoparticles. Such double-channel emission provides a broadening of the electroluminescence spectrum and a resultant yellow-green emission color of the device. We have realized an energy transfer from the exciplexes arranged by the interface between two organic layers and the spherical-shaped BaZrO3 nanoparticles randomly deposited on the organic interface constructed of the tris(4-carbazoyl-9-ylphenyl)amine and 4,7-diphenyl-1,10-phenanthroline molecules. The fabricated device exhibits a current efficiency value of 3.88 C d/A, maximum brightness of 3465 cd/m2 (at 15 V), and external quantum efficiency of about 1.26%. In order to estimate the efficiency of the energy transfer from the exciplex to the BaZrO3 nanoparticles we have applied the Förster model for the dipole-dipole energy transfer accounting for the mutual overlap of the exciplex emission spectrum and the absorption spectrum of the BaZrO3 nanoparticles.

The peculiarities of SPICE simulation of impedance spectroscopy measuring transducers are investigated in our work. On the base of model research results, an analysis method of measured values errors of the active and reactive impedance component are proposed. Our analysis method takes in to account the comparison the low-signal AC and Transient analysis. The Nyquist impedance diagrams are obtained during the AC analysis process in the idealized case, and during the Transient analysis, the active and reactive impedance components are calculated for measuring transducers actual parameters, including the activating signals forms. The implementation of such an approach is carried out by synchronous detection of output signals and integration of detection result in time range corresponding to active and reactive components. The proposed method can be used in the modeling process and sensor devices designing and in materials and nanostructures studding.

The main approaches to the parametric analysis of measuring transducers of galvanostatic type impedance on the base of SPICE-simulation are reviewed in the paper. The galvanostatic measuring method which is based on the basis of determining the value and the phase delays between the voltage and current harmonic defined amplitude and frequency was used in the process of simulation. As a result, the simulation found significant opportunity to improve the accuracy of measuring transformation by modifying the input circuits impedance measuring transducers.

The global maxima of the electro-, piezo- and acousto-optic effects are determined for langasite crystals by extreme surfaces method. The objective functions of the optimization are the normalized optical path changes/differences for the cases of electro- or piezo-optic effects and the acousto-optic figure-of-merit M2 for the case of acousto-optic effect. The optimal orientations of the control factors and the light wave vectors are defined.

We have found that the structures based on ITO/tri(9-hexylcarbazol-3-yl)amine/Ca/Al fabricated by means of vacuum deposition generate acoustic oscillations when pulse voltage is applied. Impedance spectroscopy study indicates the presence of significant inductive response, which is the result of significant energy barriers at the semiconductor-metal interface. We assume that a very heterogeneous spatial distribution of the electric field at the organic/metal interface and the noncoplanarity of the molecules cause the electrostriction effect in the structures.

We demonstrate the fabrication and properties of an near ultraviolet organic light emitting diode (UV OLED) that contains 2,7-di(9-carbazolyl)-9-(2-ethylhexyl)carbazole organic emitting layer and aluminum-doped magnesium zinc oxide (ZnMgO:Al) layer as transparent electrode. The obtained ZnMgO:Al layer is transparent for the wavelengths longer than 325 nm and has low resistivity of the order of 10-3 Ωcm. The UV OLED device turns on at the applied voltage of 9 V.

The structure and circuit of the implemented device is using an environmentally friendly radiation sources and pulse photo stimulus modes with frequencies that correspond frequencies processes in BL to create bio resonance effects to accelerate the procedures. Proposed one of the possible hardware solutions are based on usage of dynamic irradiation modes and automatic continuous optical testing procedures UIAB and PP. The changes of the optical characteristics of BL provides the doctor continuous information on the effectiveness of the procedure on the patient's condition.

In paper the effect of localized surface plasmon resonance (LSPR) in composite on the basis of glycerol with multi-walled carbon nanotubes (MWCNT) is investigated. Fabricated composites have LSPR peaks at wavelength of λ1 = 695 nm and λ2 = 702 nm. We have investigated the influence of nitrogen dioxide (NO2) with concentration in the range of 0–100 mg/m3 on the composite sample. The the wavelength of LSPR peak shifts with the change of the concentration of NO2 and follows parabolic shape curve. The maximum shift of the LSPR peak is observed to be of Δλ ≈ 5 nm.

In this article the analyses of the prospects of improving saturating procedures by improving the efficiency with the application of optical methods to monitor procedures with individual approach to each patient when carrying out physiotherapeutic procedures and allows to increase their positive impact and minimize negative.

This paper presents approaches and typical examples of model studies of transient mode characteristics for photocurrent integrators of luminescence sensors. These model studies allow to define integrator parametric dependencies on the characteristics of operational amplifiers. Research was conducted using SPICE models. A number of new laws and influence of operational amplifiers' options on the characteristics of integrators are established

An in-depth analysis of the electro-optical and light emissive properties was carried out with a new fused heteroacene, the bis [(1,2)(5,6)] indoloanthracene. The compound was synthesized in a straightforward bidirectional manner from 1,4-dibromo-2,5-diodobenzene utilizing a reaction cascade of isomerisation and cyclisation sequences. Bis-[(1,2)(5,6)] indoloanthracene exhibits bright luminescence with high quantum yield in solution as well as in the solid state. By using this novel semiconductor as active layer, an efficient OLED has been fabricated for which its emission pattern resembles at least two emitters in a single emissive region originated from the same molecule. One has its origin from the single molecule and is similar to the luminescence spectra in solution, whereas the other functions through the formation of aggregates being similar with the emission pattern found with crystals of bis-[(1,2)(5,6)]indoloanthracene. As a result bright sky-blue OLEDs with very high luminance exceeding 10000 cd/m2 were obtained. Such color pattern and performance has not previously been observed with low molecular weight, electron-rich fused polycyclic aromatic compounds and indicate a promising new class of materials for development.

We studied structural and optical properties of 5′ replaced pyrazoline by hindered phenol 2,6-di-tert.-butyl-4-(2,5-diphenyl-3,4-dihydro-2H-pyrazol-3-yl)-phenol (HPhP) films for application in organic light-emitting diode (OLED) as a hole transport layer (HTL). Analysis of impedance and current–voltage characteristics of ITO/HPhP/Al structure has shown that the current is limited by a space charged region with exponential distribution of traps near Fermi level. Characteristics of electroluminescence structure ITO/HPhP/Alq3/poly(ethylene glycol) dimethyl ether/Al was studied and analyzed. We performed the comparative analysis of luminescence time decay in two types of electroluminescent devices with HTL from pyrazolines derivative with hindered phenol and without it. We showed that hindered phenol in HTL slows down the degradation processes in OLED.

We develop the method of determining the threshold voltages of a cholesteric-nematic transition which is based on the analysis of conoscopic images. To improve the measurement accuracy of the threshold voltages and to eliminate the effect of a radiation wavelength, we propose a new method which also could be efficiently used to study the influence of surface conditions on the liquid crystal texture and to obtain the additional information about the liquid crystal texture in the process of cholesteric-nematic transition.

In this article the investigation of the cholesteric-nematic transition in thin layers of nematic-cholesteric mixtures is carried out. Nematic-cholesteric mixtures based on a nematic matrix MLC-1 with a low concentration (up to 2%) of an optically active dopant were the object of this investigation. The dependencies of threshold voltages of focal-conic deformation and forward cholesteric-nematic transition for different thicknesses of a liquid-crystal layer are obtained. It was demonstrated that the twist effect in induced cholesterics can be considered as a simple case of a cholesteric-nematic effect in thin liquid-crystal layers.

We report on stable in time organic photovoltaic devices based on metal-phthalocyanine structures, which were formed by vacuum deposition of nickel phthalocyanine (NiPc). The reported stability is due to ultra-thin zinc oxide (ZnO) layer formed at low temperature on top of the structure (beneath the metal contact) by atomic layer deposition (ALD) technique. We performed comparative analysis of current density–voltage characteristics and frequency dependencies of the impedance for freshly made ITO/NiPc/ZnO/Al and ITO/NiPc/Al devices and after storage during one month in air. We conclude that introducing of ultra-thin ZnO film into under-cathode region of ITO/NiPc/Al structure provides long-term protection of NiPc films from atmospheric effects.

The introduction of an ultrathin zinc oxide (ZnO) layer formed by the atomic layer deposition (ALD) technique was found to improve the operation parameters of nickel phthalocyanine (NiPc) based photovoltaic cells with a transparent bottom electrode, indium tin oxide (ITO). This improvement is attributed to several reasons, such as I) increase of photovoltaic yield in ITO/p-NiPc/n-ZnO/Al cells incorporating a hybrid heterojunction as compared to single-layer ITO/NiPc/Al cells, II) enhancement of the overall spectral response in the double-layer cells and III) extension of long-term operational stability.

Thin poly(o-methoxyaniline) (POMA) films have been formed by thermovacuum deposition in the temperature range of 350–450 °C and at a pressure of 5 × 10−5 Torr. The structure properties of vacuum deposited POMA films according to FTIR and UV–VIS spectra are similar to those observed for the emeraldine form of polyaniline. Current–voltage characteristics (I–V) of sandwichtype device ITO/POMA/A1 possess rectifying properties with the ideality factor ≈4 at room temperature. On the basis of the dependence of conductivity on frequency in the frequency range of 10 Hz to 1 MHz, it is shown that the Pollack–Pohl current flow hopping mechanism dominates in a polymer film; such mechanism is typical of non-ordered systems.

A general method for determining the global maximum of the linear electro-optic effect in crystalline materials based on the construction and analysis of extreme surfaces obtained as a result of the optimization procedure is proposed. The electrically induced optical path length changes for ordinary and extraordinary waves as well as the optical path difference for orthogonally polarized waves were used as the objective functions in the optimization. The objective functions were determined for units of the electric field and crystal thickness in the light pass direction. In the example of LiNbO3:MgO, it is shown that the maximal achievable given values of the optical path length change (global maxima) for ordinary and extraordinary waves are 119 pm/V and 277 pm/V, respectively. The global maximum of the optical path difference for orthogonally polarized waves is 269 pm/V (for 632.8 nm wavelength and at room temperature). These global maxima are exceeded by ∼1.5, 1.7, and 2.3 times the respective maximum values on direct cut crystals of LiNbO3:MgO and are ∼5%, 9%, or 11% larger than the global maxima for undoped LiNbO3 crystal. This ensures a possibility to increase the energy efficiency by ∼2.9 or 5.3 times in the case of using of LiNbO3:MgO crystals with optimal cuts as sensitive elements of electro-optic devices.

We have studied the use of a thin copper iodide (CuI) film as an efficient injection layer of holes from indium tin oxide (ITO) anode in a light-emitting diode structure based on tris-8-hydroxyquinoline aluminium (Alq3). The results of impedance analysis of two types of diode structures, ITO/CuI/Alq3/poly(ethylene glycol) dimethyl ether/Al and ITO/Alq3/poly(ethylene glycol) dimethyl ether/Al, are presented. Comparative analysis of their current density–voltage, luminance–voltage and impedance characteristics shows that presence of CuI layer facilitates injection of holes from ITO anode into the light-emitting layer Alq3 and increases electroluminescence efficiency of the organic light emitting diodes.

The organic solar cell based on poly(3,4-ethylenedioxythiophene)–poly(styrenesulfonate) (PEDOT:PSS)/pentacene (Pc) was fabricated using a flexible polyethyleneterephthalate (PET) substrate coated with conductive ITO layer and aluminum contact film formed on a Pc layer by electron beam deposition. The performed investigations of current–voltage characteristics indicate that the devices operate like Schottky diodes. Under illumination of an ITO/PEDOT:PSS/Pc/Al multilayer structure the photovoltaic effect is measured with open circuit voltages up to 0.5 V, short circuit current of 0.6 μA and fill factor 0.2. The spectral-photocurrent excitation profile covers a full range of visible light (380–700 nm).

We demonstrate the fabrication and properties of an near ultraviolet organic light emitting diode (UV OLED) that contains 2,7-di(9-carbazolyl)-9-(2-ethylhexyl)carbazole organic emitting layer and aluminumdoped magnesium zinc oxide (ZnMgO:Al) layer as transparent electrode. The obtained ZnMgO:Al layer is transparent for the wavelengths longer than 325 nm and has low resistivity of the order of 10−3 Ωcm. The UV OLED device turns on at the applied voltage of 9 V.

Cataloged from PDF version of article. The results of an experimental study of the electroluminescent device made of ITO/CuI/2,6-di-tert-butyl-4-(2,5-diphenyl-3,4-dihydro-2H-pyrazol-3-yl)-phenol (HPhP)/3,6-Di(9-carbazolyl)-9-(2ethylhexyl) carbazole (TCz1)/Ca:Al with efficacy up to 10.63 cd/A are presented. HPhP provides blue emission with a peak wavelength at 445 nm. The layer of TCz1 acts as an electron-transporting layer. In the framework of density functional theory (DFT) approach the geometry configuration and energy levels of HPhP are found being in a good agreement with spectral and cyclic voltammogram data. (C) 2011 Elsevier B.V. All rights reserved.

A design of secondary transducers for increase in noise immunity of photosensor device is suggested.

The construction of fibre-optic pH sensor on the base of fibre-optic and polyaniline as sensitive materials was proposed.

The models for magnetic field sensors in SPICE software for circuit simulation are considered in this paper. The new approach for synthesis of magnetodiode equivalent circuits is presented. It is shown that using combination of physical and empirical models it is possible to maintain effective analysis of sensors in specialized software for circuit simulation.