Search
Filters
total: 540
filtered: 475
Search results for: SURFACE CHARGE
-
Silver complexes stabilized by large silanethiolate ligands – crystal structures and luminescence properties
PublicationBulky silanethiolate and disiladithiolate ligands were applied to synthesize one mononuclear and three trinuclear silver complexes including two cyclic “microclusters” and a linear tri-nuclear silanethiolate complex. All obtained compounds are characterized by X-ray diffraction and FT-IR. NMR and emission spectroscopies were used where possible. The first trinuclear anionic silver thiolate is structurally characterized. The influence...
-
Exploring the cocrystallization potential of urea and benzamide
PublicationThe cocrystallization landscape of benzamide and urea interacting with aliphatic and aromatic carboxylic acids was studied both experimentally and theoretically. Ten new cocrystals of benzamide were synthesized using an oriented samples approach via a fast dropped evaporation technique. Information about types of known bi-component cocrystals augmented with knowledge of simple binary eutectic mixtures was used for the analysis...
-
Efficiency and proportions of waste tyre pyrolysis products depending on the reactor type—A review
PublicationThis article discusses the current use of different pyrolytic reactors, their constructions and operating principles regarding the yields of main products of waste tyre pyrolytic recycling. Whether one makes a larger or smaller profit, or even a loss due to a surcharge being levied on waste tyre recycling, depends on the sale of the pyrolysis products (gas, char, oil), the proportions and market prices of which differ. The cheapest...
-
Red Algae – An Alternative Source of Carbon Material for Energy Storage Application
PublicationNew electrode material obtained by pyrolysis of aquatic biomass macro (red algae) soaked with glucose solution has been characterized by SEM, EDX and Raman spectroscopy. Graphitized carbon was identified by Raman spectroscopy. Galvanostatic cyclic polarization of the materials in contact with 1M LiPF6 electrolyte in EC:DMC (1:1 v/v) and Li as a counter electrode was performed. Specific capacity of the novel material was enhanced...
-
Ammonium <i>O</i>,<i>O</i>'-diethyl dithiophosphate
PublicationIn the title compound, NH4+·(C2H5O)2PS2−, the ammonium cation is connected by four charge-assisted N−H···S hydrogen bonds to four tetrahedral O,O'-diethyl dithiophosphate anions, forming layers parallel to (100). The polar and non-polar constituents of the layers are stacked alternately along [100]. Interlacing of the external ethyl groups...
-
Production of singlet oxygen atoms by photodissociation of oxywater
PublicationQuantum chemical calculations are reported for the energies of the few lowest electronic singlet states of oxywater along dissociation of the oxygen-oxygen bond into water and singlet oxygen using multistate multireference second-order Møller–Plesset perturbation theory. We compute an energy of 21 kcal/mol to remove one oxygen atom in the lowest singlet state. The two lowest excited singlet states have vertical excitation energies...
-
Electrochemically Induced Synthesis of Triphenylamine-based Polyhydrazones
PublicationTriphenylamine-based hydrazones were subjected to electropolymerization process that gave well conductive hydrazone based polymers. The first example of polyhydrazone formation during the electrochemical process was shown. The estimation of polymer structure was demonstrated using IR spectroelectrochemistry. The EPR spectroelectrochemistry allowed to explain why in some cases dimer couldn’t be formed. The results of electrochemical,...
-
Dynamic Charging of Electric Buses as a Way to Reduce Investment Risks of Urban Transport System Electrification
PublicationNight charging and fast charging are currently the two most common systems for charging electric buses. Despite the fact that numerous trial installations were started, neither of these two systems has obtained unqualified approval of the users. The alternative is to charge vehicles in motion - dynamic charging which combines the advantages of trolleybus transport and of electric buses. One of the advantages is the reduction of...
-
Mixed, quantum-classical description of electron density transfer in the collision process
PublicationIn this work, we investigate an ion-atom model describing the time-dependent evolution of electron density during the collision. For a S3+- H system, numerical simulations are based on classical trajectory calculations, and the electron density behaviour is described with the time-dependent Schrödinger equation. We apply the finite difference method to obtain quantitative insights into the charge transfer dynamics, providing detailed...
-
Unraveling Energy Transfer and Fluorescence Quenching Dynamics in Biomolecular Complexes: A Comprehensive Study of Imiquimod-Rifampicin Interaction.
PublicationIn nature, numerous biomolecules are implicated in charge transfer (CT) and energy transfer (ET) mechanisms crucial for fundamental processes such as photosynthesis. Unveiling these mechanisms is pertinent to multiple disciplines including chemistry, engineering and biochemistry. This letter presents a study involving two molecules forming a model system with efficient ET properties. Specifically, their complex exhibits dark quenching...
-
Impedance of cation-coupled electron transfer reaction: Theoretical description of one pathway process
PublicationIt has been assumed that cation electron coupled charge transfer can be conducted in accordance with two mutually coupled reactions. Using a differential method an expression was introduced which describes the impedance of a cation electron coupled transfer reaction. Also, an electrical equivalent circuit has been defined. The total faradaic impedance is the sum of electron transfer impedance and cation transfer impedance. Issues...
-
Identification of diagnostic parameter sensitivity during dynamic processes of a marine engine
PublicationChanging some parameters of the engine structure alters the emission of harmful components in the exhaust gas. This applies in particular to the damage of charge exchange system as well as fuel system and engine supercharger. These changes are much greater during the dynamic states and their accompanying transitional processes. The different sensitivity of diagnostic parameters to the same force, coming from the engine structure, but...
-
Mutually polarizable QM/MM model with in situ optimized localized basis functions
PublicationWe extend our recently developed quantum-mechanical/molecular mechanics (QM/MM) approach [Dziedzic et al., J. Chem. Phys. 145, 124106 (2016)] to enable in situ optimization of the localized orbitals. The quantum subsystem is described with ONETEP linear-scaling density functional theory and the classical subsystem – with the AMOEBA polarizable force field. The two subsystems interact via multipolar electrostatics and are fully...
-
On the tendency of temperature and electric field dependences of interface recombination in P3HT:PCBM organic bulk heterojunction solar cells
PublicationWe demonstrate theoretical explanation of the temperature and electric field dependences of recombination coefficients in an organic P3HT:PCBM bulk heterojunction solar cell. Based onthe model of interface recombination, two analytical formulas describing the relative ratio of the interface (γI ) to the Langevin (γL) recombination coefficients have been derived. Our analysis indicates that the sign of parameters φT and φF determines...
-
Parallel computations in the volunteer based Comcute system
PublicationThe paper presents Comcute which is a novel multi-level implemen- tation of the volunteer based computing paradigm. Comcute was designed to let users donate the computing power of their PCs in a simplified manner, requiring only pointing their web browser at a specific web address and clicking a mouse. The server side appoints several servers to be in charge of execution of particular tasks. Thanks to that the system can survive...
-
Four-body recombination in organic bulk heterojunction solar cells: an alternative interpretation
PublicationWe demonstrate a new interpretation of the previously reported quadrimolecular recombination in organic bulk heterojunction solar cells. It is suggested that the recently described (Szmytkowski 2012 Phys. Status Solidi RRL 6 300) interaction between exciton and electron–hole Langevin bound pair formed across the donor–acceptor interface is a four-particle process. This is in opposition to the treatment of this effect as a three-particle...
-
Closed-form expression for the magnetic shielding constant of the relativistic hydrogenlike atom in an arbitrary discrete energy eigenstate: Application of the Sturmian expansion of the generalized Dirac–Coulomb Green function
PublicationWe present analytical derivation of the closed-form expression for the dipole magnetic shielding constant of a Dirac one-electron atom being in an arbitrary discrete energy eigenstate. The external magnetic field, by which the atomic state is perturbed, is assumed to be weak, uniform, and time independent. With respect to the atomic nucleus we assume that it is pointlike, spinless, motionless, and of charge Ze. Calculations are...
-
Hard carbon derived from rice husk as low cost negative electrodes in Na-ion batteries
PublicationHere, we report the synthesis of hard carbon materials (RH) made from natural rice husk through a single pyrolysis process and their application as an anode in sodium-ion batteries. The studies show that the electrochemical properties of RHs are affected by the treatment temperatures, which determine the materials morphology, in particular, their degree of graphitization and extent of continuous channels (nanovoids). The latter...
-
Polaron hopping conduction in manganese borosilicate glass
PublicationA study on a novel material - manganese borosilicate glass without alkali metals, was reported. It was found that the obtained samples containing high amount of manganese oxide (60MnO–xSiO2–(40 − x)B2O3, x = 5, 10, 15, 20 and 30 mol%) were amorphous and homogeneous. XPS measurements showed that most of manganese ions are at oxidation level of Mn2 + ions and the mean oxidation level slightly moves toward higher value, with increasing...
-
New Method of Non-Linear Electrochemical Impedance Spectroscopy with an Amplitude-Modulated Perturbation Signal
PublicationThe paper presents a new method of non-linear electrochemical impedance spectroscopy (NLEIS), which allows fast and nondestructive evaluation of the corrosion rate and determination of the Tafel coefficients values for a corrosion system under investigation. This method employs amplitude modulation of the ac perturbation signal. The study demonstrated that it was possible to obtain impedance characteristic as a function of the...
-
Magnetic field effects in dye-sensitized solar cells controlled by different cell architecture
PublicationThe charge recombination and exciton dissociation are generally recognized as the basic electronic processes limiting the efficiency of photovoltaic devices. In this work, we propose a detailed mechanism of photocurrent generation in dye-sensitized solar cells (DSSCs) examined by magnetic field effect (MFE) technique. Here we demonstrate that the magnitude of the MFE on photocurrent in DSSCs can be controlled by the radius and...
-
Nanocrystalline cathode functional layer for SOFC
PublicationRecently, it was shown that thin functional layers introduced between an electrolyte and cathode might improve cathode performance. However, the mechanism of this improvement still needs analysis. In this paper, a thin (∼140 nm), spin-coated perovskite layer (La0.6Sr0.4Co0.2Fe0.8O3-δ) was placed between a cathode (La0.6Sr0.4Co0.2Fe0.8O3-δ) and an electrolyte (Ce0.8Gd0.2O2-δ) and the effects of this investigated. The microstructure...
-
High-temperature transport properties of entropy-stabilized pyrochlores
PublicationIn this report, the high-temperature transport properties of (Dy1−xCax)(Zr0.2Hf0.2Sn0.2Ti0.2Ge0.2)O7 pyrochlore oxides with x = 0, 0.05, and 0.1 are studied in dry and humid air. The phase composition and crystal structure were determined by using x-ray and neutron diffraction. The addition of calcium to the structure caused an increase in the concentration of oxygen vacancies, indicating an ionic charge compensation mechanism....
-
Structure and electric transport properties of Ca-doped bulk PrBa2Cu3O7−δ
PublicationThe crystal structure and electric transport properties of Pr1-xCaxBa2Cu3O7- delta (x= 0.0, 0.1, 0.2, 0.5) bulk ceramic samples, prepared by the standard solid-state reaction in air, were examined by X-ray power diffraction, resistivity measurements and room temperature thermoelectric power determination. Ca atoms introduce additional holes to the system as well as structural defects. The orthorhombic-to-tetragonal structural...
-
Properties of Barium Cerate-Zirconate Thin Films
PublicationIn this work, we review several experimental results showing the electrical properties of barium cerate-zirconate thin films and discuss them in view of the possible influence of various factors on their properties. Most of the presented Ba(Ce, Zr, Y)O3 thin films were formed by the pulsed laser deposition (PLD) technique, however thin films prepared using other methods, like RF magnetron sputtering, electron-beam deposition, powder...
-
π-Conjugated Donor-acceptor Polyelectrolytes: Toward Artificial Photosynthesis
PublicationGreat advances have been made in the development of conjugated polyelectrolytes (CPEs), which provide tunable properties including water solubility and processability, main-chain exciton and charge transport, variable energy light absorption and fluorescence, non-covalent interactions, and formation of tertiary structures via self-assembly.[1] These characteristics allow CPEs to be considered for use in various optoelectronic applications,...
-
Evidence for solid state electrochemical degradation within a small molecule OLED
PublicationAcridone derivative have been synthesised and used as OLED (Organic Light Emitting Diode) emitters which were found to be electroactive. Electrochemical investigations showed a side reaction takes place inside an active layer which diminished the overall device efficiency. By using a dopant and host active layer architecture, the formation of the by product was removed. The by-product was identified as a σ-dimer formed inside an...
-
Novel method for metal-oxide glass composite fabrication for use in thermoelectric devices
PublicationA novel method for thermoelectric materials fabrication using a reduction of oxide precursors in hydrogen was reported. On the example of Bi-Sb, Bi-Sb-Te and Te-Ag-Ge-Sb compounds it was shown that this simple and easy method is suitable for fabrication of two-, three- and even multicomponent thermoelectric materials. It allows controlling a composition, microstructure and even type a of electrical charge carriers. As a result...
-
Extended phase diagram of RNiC2 family: Linear scaling of the Peierls temperature
PublicationPhysical properties for the late-lanthanide-based RNiC2 (R = Dy, Ho, Er, and Tm) ternary compounds are reported. All the compounds show antiferromagnetic ground state with the Néel temperature ranging from 3.4 K for HoNiC2 to 8.5 K for ErNiC2. The results of the transport and galvanomagnetic properties confirm a charge density wave state at and above room temperature with transition temperatures TCDW = 284, 335, 366, and 394 K for...
-
Three phase transient model of wet coal pyrolysis
PublicationA one-dimensional transient mathematical model was developed to describe the thermal and flow phenomena during coal pyrolysis in a coke oven. The model was solved numerically using partly implicit methods for gas flow and heat transfer problems. It was successfully validated with industrial-scale measurements of temperature change in the middle-plane of the coke oven chamber. The evolution of temperature and pressure, distributions...
-
Magnetizability of the relativistic hydrogenlike atom in an arbitrary discrete energy eigenstate: Application of the Sturmian expansion of the generalized Dirac-Coulomb Green function
PublicationThe Sturmian expansion of the generalized Dirac--Coulomb Green function [R.\/~Szmytkowski, J.\ Phys.\ B 30 (1997) 825; erratum 30 (1997) 2747] is exploited to derive a closed-form expression for the magnetizability of an arbitrary discrete state of the relativistic one-electron atom with a point-like, spinless and motionless nucleus of charge $Ze$. The result has the form of a double finite sum involving the generalized hypergeometric...
-
Modeling the electrical characteristics of P3HT:PCBM bulk heterojunction solar cells: Influence of the interface recombination
PublicationThe interface recombination of charge carriers located in the material with lower permittivity (Szmytkowski 2009 Chem.Phys.Lett. 470 123) has been implemented for the first time to calculate the electrical characteristics of the donor-acceptor P3HT:PCBM bulk heterojunction solar cell. In order to estimate the photocurrent density in this system, a simple analytical formula has been derived. We have obtained a very good agreement...
-
Ultrasonic spectroscopy of silicon single crystal
PublicationSpecimens of Si single crystals with different crystal orientation [100] and [110] were studied by the electro-ultrasonic spectroscopy (EUS) and Resonant Ultrasonic Spectroscopy (RUS). A silicon single crystal is an anisotropic crystal, so its properties are different in different directions in the material relative to the crystal orientation. EUS is based on interaction of two signals: electric AC signal and ultrasonic signal,...
-
Relativistic two-dimensional hydrogen-like atom in a weak magnetic field
PublicationA two-dimensional (2D) hydrogen-like atom with a relativistic Dirac electron, placed in a weak, static, uniform magnetic field perpendicular to the atomic plane, is considered. Closed forms of the first- and second-order Zeeman corrections to energy levels are calculated analytically, within the framework of the Rayleigh–Schrödinger perturbation theory, for an arbitrary electronic bound state. The second-order calculations are...
-
Understanding ion–ion and ion–solvent interactions in aqueous solutions of morpholinium ionic liquids with N-acetyl-L-alaninate anion through partial molar properties and molecular dynamics simulations
PublicationAmino acid ionic liquids (AAILs) provide a low toxicity, biodegradable alternative to conventional ionic liquids, while also maintaining solubility in water. Densities and sound velocities of aqueous solutions of four amino acid ionic liquids (AAILs), based on the N-alkyl-N-methylmorpholinium ([Mor1,R], R = 2, 3, 6, 8) cation and N-acetyl-L-alaninate ([N-Ac-L-Ala]) anion were measured at T = (293.15–313.15) K and at atmospheric...
-
Bis(ammonium) Zoledronate Dihydrate
PublicationNeutralization of 2-(1-imidazole)-1-hydroxyl-1,1`-ethylidenediphosphonic acid (zoledronic acid) by an excess of ammonia yielded bis(ammonium) zoledronate dihydrate, {C5H8N2O7P2 2−, 2(H4N+), 2(H2O)}. The product is readily soluble in water and forms monocrystals for which the X-ray structural analysis was carried out. The zoledronic anion is of double negative charge due to deprotonation of three P–OH groups and protonation of the...
-
Instantaneous impedance monitoring of synergistic effect between cavitation erosion and corrosion processes
PublicationThe most common method of determination of cavitation erosion resistance as well as the magnitude of erosion-corrosion synergistic interaction is based on the weight loss measurements. Nondestructive characterization of installations elements is in most cases impossible to perform. Also, such a measurement does not include local types of failure or alteration of operating conditions. There is an urge to elaborate a method for monitoring...
-
The Ellenbogen's "Matter as Software" Concept for Quantum Computer Implementation: III. Selection of X@C60 Molecular Building Blocks (MBBs) for Tip-Based Nanofabrication (TBN) of Trapped Neutral Atom Quantum Computing Devices
PublicationThe selection of guest atoms X of X@C60 MBBs for TBN of trapped neutral atom quantum computing devices is reported. Assuming the all-optical quantum computing as a final target stage, the two criteria are most important: the charge q accumulated on the C60 host must be as low as possible, and the atom X must have one or more available excited states within the band falling into the low energy window of neutral C60 molecule electronic...
-
Determination of pseudocapacitance chan ges of nickel oxide NiO electrode with use of dynamic electrochemical impedancje spectroscopy
PublicationThe electrochemical capacitors (ECs) are attractive energy storage devices which can be applied in many electronic products (e.g., cameras, laptops, cell phones) or hybrid electric vehicles (HEV). The energy storage in ECs is based on capacitive (the electrical double layer charging/discharging) and pseudocapacitive (additional charge provided by faradic reaction) phenomena. Considering the electrodes exhibiting pseudocapacitance,...
-
Widening of the electroactivity potential range by composite formation – capacitive properties of TiO2/BiVO4/PEDOT:PSS electrodes in contact with an aqueous electrolyte
PublicationComposites based on the titania nanotubes were tested in aqueous electrolyte as a potential electrode material for energy storage devices. The nanotubular morphology of TiO2 was obtained by Ti anodization. TiO2 nanotubes were covered by a thin layer of bismuth vanadate using pulsed laser deposition. The formation of the TiO2/BiVO4 junction leads to enhancement of pseudocapacitance in the cathodic potential range. The third component,...
-
Heterojunction of (P, S) co-doped g-C3N4 and 2D TiO2 for improved carbamazepine and acetaminophen photocatalytic degradation
PublicationNovel photocatalysts of phosphorus and sulfur co-doped graphitic carbon nitride incorporated in 2D TiO2 structure were successfully fabricated and applied for solar-driven degradation of emerging pollutants from the group of pharmaceuticals not susceptible to biodegradation. The hybrid photocatalysts with different loadings of (P, S)-doped g-C3N4 were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR),...
-
Adaptable management for cooling cyclic air in ship power plants by heat conversion – Part 1: Downsizing strategy for cogeneration plants
PublicationThe ship power plants (SPP) are generally based on Diesel engines. Their fuel efficiency is gradually sensible to cyclic air temperatures and drops with their rise. A sustainable performance of ship engines with high fuel efficiency is possible by cooling intake and charge air as two objects in waste heat conversion chillers. The peculiarities of marine engine application are associated with constrained space of machine room. Whereas,...
-
Designing high-performance asymmetric and hybrid energy devices via merging supercapacitive/pseudopcapacitive and Li-ion battery type electrodes
PublicationWe report a strategic development of asymmetric (supercapacitive–pseudocapacitive) and hybrid (supercapacitive/pseudocapacitive–battery) energy device architectures as generation–II electrochemical energy systems. We derived performance-potential estimation regarding the specific power, specific energy, and fast charge–discharge cyclic capability. Among the conceived group, pseudocapacitor–battery hybrid device is constructed with...
-
Hopping or Tunneling? Tailoring the Electron Transport Mechanisms through Hydrogen Bonding Geometry in the Boron-Doped Diamond Molecular Junctions
PublicationMechanisms of charge transport in molecular junctions involving hydrogen bonds are complex and remain mostly unclear. This study is focused on the elucidation of the electron transfer in a molecular device consisting of two boron-doped diamond interfaces bound with an aromatic linker and a hydrogen bonding surrogating molecule. The projected local density of states (PLODS) analysis coupled with transmission spectra and current−voltage...
-
The Effect of C45 Carbon Black-Phosphomolybdic Acid Nanocomposite on Hydrogenation and Corrosion Resistance of La2Ni9Co Hydrogen Storage Alloy
PublicationIn this paper, we analysed the influence of corrosion processes and the addition of a carbon black-heteropoly phosphomolybdic acid (C45-MPA) nanocomposite on the operating parameters of a hydride electrode obtained on the basis of the intermetallic compound La2Ni9Co. The electrochemical properties of negative electrodes for NiMH batteries were studied using galvanostatic charge/discharge curves, the potentiostatic method, and electrochemical...
-
Designing efficient A-D-A1-D-A type fullerene free acceptor molecules with enhanced power conversion efficiency for solar cell applications
PublicationThe achievement of highly efficient power conversion efficiency (PCE) is a big concern for non-fullerene organic solar cells (NF-OSCs) because PCE can depend on numerous variables. Here, new five novel acceptor molecules without fullerenes were developed and investigated using DFT (density functional theory) and TD-DFT (time dependent-density functional theory). Compared to the recently synthesized molecule (PZ-dIDTC6), the developed...
-
Additive Effect of Bromides and Chlorides on the Performance of Perovskite Solar Cells Fabricated via Sequential Deposition
PublicationA two-step sequential deposition method has been applied to prepare the solar cells with two types of perovskites Cs0.15FA0.85Pb(I0.95Cl0.05)3 and Cs0.15FA0.85Pb(I0.95Br0.05)3. In order to obtain the perovskite layers, the different sources of bromine and chlorine atoms were used for synthesis. The performance and time stability of chloride-based photocells are worse in comparison to the bromide-based devices. It can be explained...
-
A Theoretical and Experimental Study of Moderate Temperature Alfa Type Stirling Engines
PublicationThe Stirling engine is a device that allows conversion of thermal energy into mechanical energy with relatively high efficiency. Existing commercial designs are mainly based on the usage of high temperature heat sources, whose availability from renewable or waste heat sources is significantly lower than that of moderate temperature sources. The paper presents the results of experimental research on a prototype alpha type Stirling...
-
Advanced Lithium-Ion Battery Model for Power System Performance Analysis
PublicationThe paper describes a novel approach in battery storage system modelling. Different types of lithium-ion batteries exhibit differences in performance due to the battery anode and cathode materials being the determining factors in the storage system performance. Because of this, the influence of model parameters on the model accuracy can be different for different battery types. These models are used in battery management system...
-
Two kinds of oxygen vacancies in lithium titaniate doped with copper as detected by EPR
PublicationLithium titanate (Li1+xTi2-xO4) doped with Cu2+ ions was synthesized by sol-gel processing method. The structure and morphology are characterized by X-ray Diffraction (XRD), X-ray Photoemission Spectroscopy (XPS), Scanning Electron Microscopy (SEM) and Electron Paramagnetic Resonance (EPR). Spin Hamiltonian parameters describing Zeeman and hyperfine interaction for 63Cu2+ ions were obtained from EPR spectra simulations. The spectra...