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Search results for: LAMP OF VARIABLE SPECTRUM
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Unidirectional DC/DC Converter with Voltage Inverter for Fast Charging of Electric Vehicle Batteries
PublicationThe paper proposes the adaptation of the industrial plant’s power network to supply electric vehicle (EV) fast-charging converters (above 300 kW) using renewable energy sources (RESs). A 600 V DC microgrid was used to supply energy from RESs for the needs of variable speed motor drives and charging of EV batteries. It has been shown that it is possible to support the supply of drive voltage frequency converters (VFCs) and charging...
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Nanoindentation tests titanium alloy Ti-6Al-4V after interference laser treatment
PublicationThe study aimed was to assess selected mechanical properties of surface layers obtained after interference laser treatment – DLIL of titanium alloy Ti-6Al-4V used for implants. The samples were melted in still air at room temperature, for this purpose Nd:YAG laser was used, the number of laser shots was variable. Next, nanoindentation tests were performed, based on which Young’s modulus and nanohardness in the obtained surface...
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Pareto Ranking Bisection Algorithm for EM-Driven Multi-Objective Design of Antennas in Highly-Dimensional Parameter Spaces
PublicationA deterministic technique for fast surrogate-assisted multi-objective design optimization of antennas in highly-dimensional parameters spaces has been discussed. In this two-stage approach, the initial approximation of the Pareto set representing the best compromise between conflicting objectives is obtained using a bisection algorithm which finds new Pareto-optimal designs by dividing the line segments interconnecting previously...
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Guided ultrasonic waves for detection of debonding in bars partially embedded in grout
PublicationThis paper deals with theoretical, numerical and experimental investigations of guided wave propagation in multilayered cylindrical bars with pre-existing debonding. The research focuses on a complex description of the nature of the wave phenomena occurring in a debonded specimen with a special emphasis on the influence of the location of damage on the wave conversion and diffraction. Experimental non-destructive and destructive...
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Specificity of Infant Digestive Conditions: Some Clues for Developing Relevant In Vitro Models
PublicationDigestion of nutrients is an essential function of the newborn infant gut to allow growth and development and understanding infant digestive function is essential to optimize nutrition and oral drug delivery. Ethical considerations prohibit invasive in vivo trials and as a consequence in vitro assays are often conducted. However, the choice of in vitro model parameters are not supported by an exhaustive analysis of the literature...
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Assessing groundwater vulnerability to pollution in the Puck region (denudation moraine upland) using vertical seepage method
PublicationDegradation of groundwater quality can cause a serious water supply and environmental problems. The identify of potential groundwater pollution can be determined by assessment of groundwater vulnerability method. The assessment of groundwater vulnerability to pollution was based on estimation of migration time of potential conservative contamination through the vadose zone. Area of investigation is a type of denudation moraine...
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Speed observer of induction machine based on backstepping and sliding mode for low‐speed operation
PublicationThis paper presents a speed observer design based on backstepping and slidingmode approaches. The inputs to the observer are the stator current and thevoltage vector components. This observer structure is extended to the integra-tors. The observer stabilizing functions contain the appropriate sliding surfaceswhich result from the Lyapunov function. The rotor angular speed is obtainedfrom the non‐adaptive formula with a sliding...
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Nonlinear planar modeling of massive taut strings travelled by a force-driven point-mass
PublicationThe planar response of horizontal massive taut strings, travelled by a heavy point-mass, either driven by an assigned force, or moving with an assigned law, is studied. A kinematically exact model is derived for the free boundary problem via a variational approach, accounting for the singularity in the slope of the deflected string. Reactive forces exchanged between the point-mass and the string are taken into account via Lagrange...
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Debonding Detection in Reinforced Concrete Beams with the Use of Guided Wave Propagation
PublicationOne of the most frequent damage of the reinforced concrete structures is debonding between steel bar and concrete cover. In the case of debonding occurrence not only the strength of the structure decreases, but also it is more vulnerable to corrosion damages. For this reason fast and effective methods of debonding detection in an early stage of its development need a significant boost. The paper presents analytical and experimental...
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Within- and between-person factor structure of the Oldenburg Burnout Inventory: Analysis of a diary study using multilevel confirmatory factor analysis
PublicationThe study examined the factor structure of burnout, as measured with the Oldenburg Burnout Inventory. The participants were 235 employees of a public administration agency who assessed their burnout online for 10 consecutive working days. Two models were tested with multilevel confirmatory factor analysis, assuming the same one or two-factor structure at the within- and between-person levels. Both models showed a reasonable fit...
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SLIDING MODE-PID FUZZY CONTROLLER WITH A NEW REACHING MODE FOR UNDERWATER ROBOTIC MANIPULATORS
PublicationDesign of an accurate and robust controller is a challenging topic in an underwater manipulator control. This is due to hydrodynamic disturbances in underwater environment. In this paper a sliding mode control (SMC) included a PID sliding surface and fuzzy tunable gain is designed. In this proposed controller robustness property of SMC and fast response of PID are incorporated with fuzzy rules to reduce error tracking. In the...
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Effects of Surface Energy and Surface Residual Stresses on Vibro-Thermal Analysis of Chiral, Zigzag, and Armchair Types of SWCNTs Using Refined Beam Theory
PublicationIn this article, vibration characteristics of three different types of Single-Walled Carbon Nanotubes (SWCNTs) such as armchair, chiral, and zigzag carbon nanotubes have been investigated considering the effects of surface energy and surface residual stresses. The nanotubes are embedded in the elastic substrate of the Winkler type and are also exposed to low and high-temperature environments. A new refined beam theory namely, one-variable...
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Application of electrochemical impedance spectroscopy to monitoring discharging process of nickel/metal hydride battery.
PublicationThis paper presents the possibility of applying impedance analysis to cell diagnostics. In order to obtain characteristic curves of both electrodes of a NiMH battery simultaneously, a reference electrode was added into the circuit. The authors analysed the cell under three cases, i.e. when its properties are determined only by the state of the positive electrode, only by the state of the negative electrode, or when both electrodes...
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On structural physical approximations and entanglement breaking maps
PublicationVery recently, a conjecture saying that the so-called structural physical approximations (SPAs) to optimal positive maps (optimal entanglement witnesses) give entanglement breaking (EB) maps (separable states) has been posed (Korbicz et al 2008 Phys. Rev. A 78 062105). The main purpose of this contribution is to explore this subject. First, we extend the set of entanglement witnesses supporting the conjecture. Then, we ask whether...
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Structural Heterogeneity Between EU15 and 12 New EU Members – the Obstacle to Lisbon Strategy Implementation
PublicationThe aim of this article is to identify diversity between the EU-15 and the New Members in their implementation of the Lisbon Strategy in the period 2000-2010. By analyzing a set of structural indicators, we aim to fill a gap in the literature: a lack of publications providing complex evaluation of the implementation of the Lisbon Strategy using measurable indicators. Given their suitability for international comparisons, we use...
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Electroelastic biaxial compression of nanoplates considering piezoelectric effects
PublicationIn the present theoretical work, it is assumed that a piezoelectric nanoplate is connected to the voltage meter which voltages have resulted from deformation of the plate due to in-plane compressive forces whether they are critical buckling loads or arbitrary forces. In order to derive governing equations, a simplified four-variable shear deformation plate theory has been employed using Hamilton’s principle and Von-Kármán...
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Wild oscillations in a nonlinear neuron model with resets: (I) Bursting, spike-adding and chaos
PublicationIn a series of two papers, we investigate the mechanisms by which complex oscillations are generated in a class of nonlinear dynamical systems with resets modeling the voltage and adaptation of neurons. This first paper presents mathematical analysis showing that the system can support bursts of any period as a function of model parameters, and that these are organized in a period-incrementing structure. In continuous dynamical...
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Radio Channel Measurements in 868 MHz Off-Body Communications in a Ferry Environment
PublicationIn this paper, a characterization of the 868 MHz off-body radio channel in BANs is presented. Measurements were carried out in a ferry environment using a specific set-up. A method for path loss using radio distance measurements (RDMs) was developed. It allows to automate the measurements process and make it independent from the variable speed of a moving person. Based on the observed path loss as a function of distance, the obtained...
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Some aspects of noise generated by a small ship in the shallow sea
PublicationThe passing and underwater moving objects produce the noises of variable intensity, which significantly increase the overall level of noise in the sea. This applies to both the sonic and ultrasonic range. The excessive levels of underwater noise adversely affects the so-called underwater acoustic climate and is the reason why this phenomenon is intensively investigated from the number of years. The results of experimental work...
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Induction Generator with Direct Control and a Limited Number of Measurements on the Side of the Converter Connected to the Power Grid
PublicationThe article presents an induction generator connected to the power grid using the AC/DC/AC converter and LCL coupling filter. Three-level inverters were used in the converter, both from the generator side and the power grid side. The algorithm realizing Pulse Width Modulation (PWM) in inverters has been simplified to the maximum. Control of the induction generator was based on the Direct Field-Oriented Control (DFOC) method. At...
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Adoption of the F-statistic of Fisher-Snedecor distribution to analyze importance of impact of modifications of injector opening pressure of a compression ignition engine on specific enthalpy value of exhaust gas flow
PublicationThis article analyzes the effect of modifications of injector opening pressure on the operating values of a compression ignition engine, including the temperature of the fumes. A program of experimental investigation is described, considering the available test stand and measurement capabilities. The structure of the test stand on which the experimental measurements were conducted is presented. The method of introducing real modifications...
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Bacterial cellulose vs. bacterial cellulose nanocrystals as stabilizer agents for O/W pickering emulsions
PublicationThe growing interest in Pickering emulsions in functional food systems resulted in the need to find suitable stabilizers for them. The work considers the use of bacterial cellulose for this purpose, and its aim was to compare the properties of disintegrated bacterial cellulose, before and after freeze-drying, and its nanocrystals obtained using H2SO4 under variable of time and concentration conditions. The structure of nanocrystals...
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Implementation of an Adaptive Method for Changing the Frequency Division of the Counter Clock Signal in a Frequency-to-Code Converter
PublicationProcessing physical quantities into an indirect signal is a standard method of transferring information about the measured quantity to the master system, which analyzes the data obtained from the acquisition system. The intermediate signal is very often the voltage, but another transmission medium can be the frequency of the output signal of the “physical quantity-to-frequency” converter. The article presents the implementation...
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Transient response of oscillated carbon nanotubes with an internal and external damping
PublicationThe present works aims at modeling a viscoelastic nanobeam with simple boundary conditions at the two ends with the introduction of the Kelvin-Voigt viscoelasticity in a nonlocal strain gradient theory. The nanobeam lies on the visco-Pasternak matrix in which three characteristic parameters have a prominent role. A refined Timoshenko beam theory is here applied, which is only based on one unknown variable, in accordance with the...
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COVID-19 severity forecast based on machine learning and complete blood count data
PublicationProper triage of COVID-19 patients is a key factor in eective case management, especially with limited and insucient resources. In this paper, we propose a machine-aided diagnostic system to predict how badly a patient with COVID-19 will develop disease. The prognosis of this type is based on the parameters of commonly used complete blood count tests, which makes it possible to obtain data from a wide range of patients.We chose...
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COVID-19 severity forecast based on machine learning and complete blood count data
PublicationProper triage of COVID-19 patients is a key factor in eective case management, especially with limited and insucient resources. In this paper, we propose a machine-aided diagnostic system to predict how badly a patient with COVID-19 will develop disease. The prognosis of this type is based on the parameters of commonly used complete blood count tests, which makes it possible to obtain data from a wide range of patients.We chose...
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Periodic and chaotic dynamics in a map‐based neuron model
PublicationMap-based neuron models are an important tool in modeling neural dynamics and sometimes can be considered as an alternative to usually computationally costlier models based on continuous or hybrid dynamical systems. However, due to their discrete nature, rigorous mathematical analysis might be challenging. We study a discrete model of neuronal dynamics introduced by Chialvo in 1995. In particular, we show that its reduced one-dimensional...
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Influence of Honing Parameters on the Quality of the Machined Parts and Innovations in Honing Processes
PublicationThe article presents a literature review dealing with the effect of the honing parameters on the quality of the machined parts, as well as with the recent innovations in honing processes. First, an overview about the honing and the plateau-honing processes is presented, considering the main parameters that can be varied during machining. Then, the influence of the honing parameters on surface finish, shape deviation and material...
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SZACOWANIE ZAWARTOŚCI BENZO(a)PIRENU W PYLE ZAWIESZONYM PM10 W AGLOMERACJI TRÓJMIEJSKIEJ ZA POMOCĄ WIELOWYMIAROWEJ REGRESJI LINIOWEJ=ESTIMATION OF BENZO(A)PYRENE CONTENT IN SUSPENDED DUST PM10 IN TRI-CITY AGGLOMERATION USING MULTIDIMENSIONAL LINEAR REGRESSION
PublicationW pracy przedstawiono próbę oszacowania przy pomocy wielowymiarowej regresji liniowej modelu empirycznego opisującego czynniki wpływające na zawartość B(a)P w pyle zawieszonym PM10 w Aglomeracji Trójmiejskiej w latach 2008-2011. Na przestrzeni tych lat średnioroczne stężenie B(a)P w PM10 wzrosło ponad dwukrotnie i ponad trzykrotnie przewyższa poziom docelowy. Z przeprowadzonych analiz wynika, że główną przyczyną wzrostu stężenia...
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WERYFIKACJA KONCEPCJI PRZEGUBÓW PLASTYCZNYCH PROJEKTOWANYCH NA ODZIAŁYWANIA SEJSMICZNE WIADUKTU V6 OBWODNICY ISTAMBUŁU
PublicationW pracy zawarto wyniki analiz betonowego wiaduktu V6 budowanego w ciągu obwodnicy Istambułu w Turcji realizowanego w ramach projektu Northern Marmara Highway. Przeprawę stanowią dwie niezależne nitki o skrzynkowym przekroju poprzecznym i szerokości 22,00 m. Schemat statyczny obiektu to belka dziewięcioprzęsłowa o długości całkowitej 446,86 m oparta na podporach słupowych o zmiennej sztywności (rys.1) i wysokościach zmieniających...
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Molecular differences in mitochondrial DNA (mtDNA) genomes of dogs with malignant mammary tumours
Open Research DataThe aim of this study was to determine molecular defects in mitochondrial DNA with the use of large-scale genome analysis in malignant canine mammary gland tumours and indicate whether these changes were linked with the carcinogenesis process. With the use of the NGS technology, we sequenced 27 samples of mtDNA isolated from blood and tumours obtained...
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Identification of intermetallic phases in the structure of austenitic steel with use of Scanning Kelvin Probe Microscopy
Open Research DataDelta ferrite is formed in austenitic steels during the solidification of the alloy and its welds. It can also occur as a stable phase in any temperature range in high-alloy austenitic-ferritic steels. Depending on the amount, it can change into gamma and sigma phases and into ferrite with variable chromium content. The main role of delta ferrite in...
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SYNAT Music Genre Parameters PCA 19
Open Research DataThe dataset contains feature vector after Principal Component Analysis (PCA) performing, so there are 11 music genres and 19-element vector derived from music excerpts. Originally, a feature vector containing 173 elements was conceived in earlier research studies carried out by the team of authors [1-6]. A collection of 52532 music excerpts described...
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SYNAT_PCA_48
Open Research DataThere is a series of datasets containing feature vectors derived from music tracks. The dataset contains 51582 music tracks (22 music genres) and feature vector after Principal Component Analysis (PCA) performing, so there are 48-element vectors derived from music excerpts. Originally, a feature vector containing 173 elements was conceived in earlier...
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SYNAT_PCA_11
Open Research DataThe dataset contains 51582 music tracks (22 music genres) and feature vector after Principal Component Analysis (PCA) performing, so there are 11-element vectors derived from music excerpts. Originally, a feature vector containing 173 elements was conceived in earlier research studies carried out by the team of authors [1-6]. A collection of more than...
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Theoretical Investigation of the Electron-Transfer Dynamics and Photodegradation Pathways in a Hydrogen-Evolving Ruthenium-Palladium Photocatalyst
PublicationTime-dependent density functional theory calcula- tions combinedwith the Marcus theory of electron transfer (ET) were app lied on the molecular photocatalys t [(tbbpy) 2 Ru(tpph z)PdC l 2 ] 2 + in order to elucidate thelight-in- duced relaxation pathways populated upon excitation in the longer wavelength range of its absorption spectrum. The computational resultsshow that after the initial excitation, metal (Ru) to ligand (tpphz)chargetransfer...
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Comparison of Two Methods for the Determination of Selected Pesticides in Honey and Honeybee Samples
PublicationDeveloped and validated analytical methods for the determination of a wide spectrum of pesticide residues in honey and honeybee samples after the modification of QuEChERS extraction in combination with gas chromatography–tandem quadrupole mass spectrometry (GC-MS/MS) and liquid chromatography–tandem quadrupole mass spectrometry (LC-MS/MS) were discussed and compared. The developed methods were evaluated regarding the utilized equipment...
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Automatic detection and correction of detuned singing system for use with query-by-humming applications
PublicationThe aim of the paper is to present an idea of using the automatic detection and correction of detuned singing as a subsystem in query-by-humming (QBH) applications. The common approach to searching for a requested song basing on the melody retrieved from hummed pattern usually employs the so-called Parsons code or melody contour. In such a case information about sound pitch is discarded. It was thought out that an additional module...
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Krajobraz nomadyczny w Muittalus samid birra (1910) Johana Turiego
PublicationThe article introduces Muittalus samid birra (1910, An account of the Sami) by Johan Turi, the fi rstbook with a secular content written in the sami language by a sami person. The author, a wolf hunterand reindeer-breeder, describes a broad spectrum of his people’s daily life. Pictures of everydayactivities are supplemented with stories about the sami people’s knowledge of the world (traditions,myths,...
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An Assessment of RASSCF and TDDFT Energies and Gradients on an Organic Donor−Acceptor Dye Assisted by Resonance Raman Spectroscopy
PublicationThe excitation energies and gradients in the ground and the first excited state of a novel donor−(π- bridge)−acceptor 4-methoxy-1,3-thiazole-based chromophore were investigated by means of MS-RASPT2/RASSCF and TDDFT in solution. Within both methods, the excitation energies strongly depend on the employed equilibrium structures, whose differences can be rationalized in terms of bond length alternation indexes. It is shown that functionals with...
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Chemical composition of shells from red (Strongylocentrotus franciscanum) and green (Strongylocentrotus droeba-chiensis) sea urchin
PublicationThe shells from red and green sea urchins accounted for 47.9 and 40.7% of their body weights, respectively. The red and green sea urchin shells contained 91.08 and 90.77% minerals and 4.06 and 4.99% proteins, respectively. The shells did not contain any chitin. Sea urchin shells had a relatively large amount of naphthoquinone pigments, 121 mg per 100 g in red and 163 mg per 100 g in green species. The small quantities of glucosamine...
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Time-Domain Description of Point-Source Acoustic Wavefields as a Useful Approach in Ultrasonic Techniques
PublicationIn traditional acoustics, field problems are usually treated in the frequency domain, broadband fields being reduced to superposition of harmonic spectrum components. However, this approach is inherently acausal and it is known that in case of arbitrary signals, the distribution-based, time-domain description can be more effective. The present paper is an attempt to expand the time-domain linear systems formalism onto space problems...
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Reliable routing and resource allocation scheme for hybrid RF/FSO networks
PublicationSignificant success of wireless networks in the last decade has changed the paradigms of communication networks design. In particular, the growing interest in wireless mesh networks (WMNs) is observed. WMNs offer an attractive alternative to conventional cable infrastructures, especially in urban areas, where the cost of new installations is almost prohibitive. Unfortunately, the performance of WMNs is often limited by the cluttered...
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Analytics of Surfactants in the Environment: Problems and Challenges
PublicationSurfactants (surface active agents = SAAs) are a group of compoundswith specific physicochemical properties (amphiphilicity,solubility in polar and nonpolar liquids, ability to form micelles,adsorption at phase boundaries).1,2 Because of their properties,surface-active compounds are widely applied in industry and thehousehold (e.g., in detergents, personal-care products, paints,pesticides, petroleum products). As their applications...
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Green Sample Collection
PublicationThe term of “green sample collection” is directly associated with both passive and dynamic analytical tools which allow for simultaneous management of the stage of collection and isolation and/or enrichment of a broad spectrum of chemical compounds from environmental samples. The use of passive sampling techniques at the stage of sample collection makes it possible to obtain in a simple yet inexpensive manner an analytical information...
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Configurations of H 3 + (H2)n clusters and their energies
PublicationThe H-3(+) ion plays an important role in low temperature astrophysical and laboratory plasmas. It is considered as the initiator of many ion-molecule chemistries. Also its clusters with H-2 are quite interesting. We study configurations of the H-3(+)(H-2)(n) clusters for n = 1 up to n = 12 as a simple test system. Total energies for these structures, with zero point vibration corrections have been calculated. Stabilization energies...
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Non-Gaussian Resistance Fluctuations in Gold-Nanoparticle-Based Gas Sensors: An Appraisal of Different Evaluation Techniques
PublicationVolatile organic compounds, such as formaldehyde, can be used as biomarkers in human exhaled breath in order to non-invasively detect various diseases, and the same compounds are of much interest also in the context of environmental monitoring and protection. Here, we report on a recently-developed gas sensor, based on surface-functionalized gold nanoparticles, which is able to generate voltage noise with a distinctly non-Gaussian...
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Photoelectron spectroscopy of a series of acetate and propionate esters
PublicationThe electronic state and photoionization spectroscopy of a series of acetate esters: methyl acetate, isopropyl acetate, butyl acetate and pentyl acetate as well as two propionates: methyl propionate and ethyl propionate, have been determined using vacuum-ultraviolet photoelectron spectroscopy. These experimental investigations are complemented by ab initio calculations. The measured first adiabatic and vertical ionization energies...
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Low-Barrier Hydrogen Bond Determines Target-Binding Affinity and Specificity of the Antitubercular Drug Bedaquiline
PublicationThe role of short strong hydrogen bonds (SSHB) in ligand-target binding remains largely unexplored, thereby hin- dering a potentially important avenue in the rational drug de- sign. Here, we investigate the interaction between bedaquiline (Bq), a potent anti-tuberculosis drug, and the mycobacterial ATP synthase, to unravel the role of a specific hydrogen bond to a conserved acidic residue in the target affinity and specificity....
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Comparison of Doppler Effect Estimation Methods for MFSK Transmission in Multipath Hydroacoustic Channel
PublicationUnderwater wireless communication remains a challenging topic, particularly for applications such as wreck penetration where multipath and Doppler effects are very intense. These effects are becoming even more difficult to mitigate for fast data transmission systems that utilize wideband signals. Due to the low propagation speed of acoustic wave in the water, there is a significant difference between the Doppler shift for lower...