Filters
total: 9214
-
Catalog
displaying 1000 best results Help
Search results for: TWO-PHASE FLOW
-
“Shadow” vs. “Phase 3D” method within endoscopic examinations of marine engines
PublicationA visual investigation of surfaces creating internal, working spaces of marine combustion engines by means of specialized view-finders so called endoscopes is at present almost a basic method of technical diag-nostics. The surface structure of constructional material is visible during investigations like through the magnifying glass (usually with a precisely determined magnification), which makes possible a detection, recognition...
-
Impact response of two-layered grouted aggregate fibrous concretecomposite under falling mass impact
PublicationTwo-layered Grouted Aggregates Fibrous Concrete Composite (TGAFCC) is a new category concrete which became popular recently and attracted the attention of researchers globally. Recent studies indicated that TGAFCC has notable improvement in mechanical properties, which has been sufficiently documented. However, the impact behaviour of TGAFCC when combined with Glass Fibre Mesh (GFM) and Textile Fibre Mesh (TFM) is still unexplored....
-
Expedited two-objective dimension scaling of compact microwave passives using surrogate models
PublicationGeometry scaling of compact microwave structures is a challenging problem because of complex relationships between the physical dimensions and electrical characteristics, mostly caused by considerable cross-couplings in densely arranged layouts. Here, a procedure for expedited dimension scaling of compact microwave couplers with respect to two independent criteria has been presented. Our approach involves inverse surrogate models...
-
Experimental study and comparison with predictive methods for flow boiling heat transfer coefficient of HFE7000
PublicationThis article describes an experimental study of flow boiling of HFE7000 inside a smooth vertical channel. The investigation has been carried out in a circular stainless-steel tube with an inner diameter of 2.3 mm. The data have been collected for the applied heat fluxes q ranging from 61 to 205 kW/m2, the mass flux G ranging from 214 to 1006 kg/(m2 s), the saturation temperature Tsat ranging from 30 to 54 °C and the full range...
-
Global Complex Roots and Poles Finding Algorithm Based on Phase Analysis for Propagation and Radiation Problems
PublicationA flexible and effective algorithm for complex roots and poles finding is presented. A wide class of analytic functions can be analyzed, and any arbitrarily shaped search region can be considered. The method is very simple and intuitive. It is based on sampling a function at the nodes of a regular mesh, and on the analysis of the function phase. As a result, a set of candidate regions is created and then the roots/poles are verified...
-
DEM investigations of two-dimensional granular vortex- and anti-vortex- structures during plane strain compression.
PublicationDEM investigations of two-dimensional granular vortex- and anti-vortex- structures during plane strain compression.
-
Potential and limits of landfill leachate treatment in a multi-stage subsurface flow constructed wetland – evaluation of organics and nitrogen removal
PublicationConstructed wetlands have potential of treating wastewater of poor biodegradability. The performance of a multistage sub-surface flow wetland treating municipal landfill leachate was assessed during three years of operation. During the study three research periods with different operation conditions were established. The hydralic loads, operation mode of vertical flow beds and type of treated wastewater (raw leachate – leachate...
-
Two classes of capillary optical fibers: refractive and photonic
Publication -
Analysis of two design kind of propulsion for an inland vessel
PublicationW artykule przedstawiono założenia projektowe i dwa rozwiązania konstrukcyjne układu napędowego dla statku śródlądowego. W jednym z tych rozwiązań zastosowano przekładnię hydrostatyczną zaś w drugim - przekładnię elektryczną z przetwornikiem częstotliwości. Ponadto przedstawiono analizę porównawczą obu opracowanych układów.
-
Oxygen deficient YBa2Cu3O7-r: two superconducting phases
PublicationZestaw próbek ceramiki YBa2Cu3O7-r w postaci pudru i granulatupoddawano stopniowemu odtlenianiu i badano za pomocątermograwimetrii oraz absorbcji mikrofalowej. Stosowanie tychmetod pokazało, że występująca faza $Trm_c=60$~K w związkuYBa2Cu3O7-r, powstała poprzez odtlenianie jest niestabilna.
-
Analysis of two design kind of propulsion for an inland vessel
Publicationw artykule przedstawiono dwa rodzaje układu napędowego dla statku śródlądowego. Pierwszy układ diesel-elektryczny z przetwornikiem częstotliwości i drugi układ diesel-hydrauliczny z przekładnią hydrostatyczną. Przeprowadzono wstępną analizę porównawczą obu układów z uwzględnieniem gabarytów, mas, kosztów inwestycyjnych i sprawności.
-
Rich Bifurcation Structure in a Two-Patch Vaccination Model
Publication -
Two-Boson Correlations in Various One-Dimensional Traps
Publication -
Two-electron entanglement in elliptically deformed quantum dots
Publication -
Capturing nonexponential dynamics in the presence of two decay channels
Publication -
Entanglement of Two Charged Bosons in Strongly Anisotropic Traps
Publication -
Quantum Entanglement of Two Harmonically Trapped Dipolar Particles
Publication -
Structure-Activity Relationships in Two-Electron Reduction of Quinones
Publication -
Human Geomatics in Urban Design—Two Case Studies
Publication -
Open water experiments with two pod propulsor models.
PublicationReferat przedstawia obszerne eksperymenty hydromechaniczne z dwoma modelami pędników podowych. Jeden z nich jest pędnikiem pchającym o średnicy 0,32 m, drugi pędnikiem ciągnącym o średnicy 0,25 m. W trakcie pomiarów ustalono przebieg sześciu składowych siły i momentu hydrodynamicznego dla szerokiego zakresu zmian współczynnika posuwu i kąta dryfu.
-
Two dimensional inverse method of turbomachinery stage design
PublicationW artykule przedstawion rys historyczny dotyczący modelu osiowo-symetrycznego w zastosowaniu do maszyn wirnikowych. Została sformułowana metoda rozwiązywania zadania odwrotnego polegaająca na znajdywaniu powierzchni będfącej obrazem łopatki w osiowo symetrycznym modelu maszyny wirnikowej. Zaprezentowano przykłady zastosowania tej metody w odniesieniu do łopatki kierowniczej turbiny, spreżarki promieniowej oraz pompo-turbiny.
-
Reexamination of determinant-based separability test for two qubits
PublicationPrzeanalizowano wyznacznikowy test splątania dwukubitowego pod kątem związku z inną miarą splątania- zgodnością. Udowodniono prawo faktoryzacji i przeformułowano relację monogamii splątania przy użyciu wyznacznikowego parametru splątania.
-
TWO-SHAFT GAS TURBINE TEACHING AND TESTING STATION
PublicationThe station was established as part of a project co-financed by the European Union with the funds of the European Regional Development Fund as part of the Infrastructure and Environment Operational Programme titled: “Establishment of state-of-the-art technical infrastructure for the Engineers of the Future learning programme at the Gdańsk University of Technology” executed in 2013-2015.
-
Design and realization of two-operand modular adders in the FPGA
PublicationW pracy zaprezentowano strukturę sumatorów modularnych w środowisku Xilinx z użyciem rodziny układów Virtex-6. Rozważono dwa typy sumatorów, jeden dla modułów 5-bitowych i drugi dla 6-bitowych. Zaprojektowano ich struktury i podano eksperymentalne wyniki implementacji.
-
Tuning the extraction properties of ionogel-coated Solid-phase microextraction fibers based on the solvation properties of the ionic liquids
PublicationA silica-based network was used to immobilize ionic liquid-based ionogels and applied as a fiber coating forsolid-phase microextraction (SPME). The ionogels were prepared by a sol–gel process, using two ionic liquids,triethylsulfonium bis(trifluoromethylsulfonyl)imide ([Set3][TFSI]) and 1-butyl-1-methylpiperidinium bis(tri-fluoromethylsulfonyl)imide ([C4C1Pip][TFSI]), as well as their equimolar mixture. Methyltrimethoxysilane wasused...
-
Two-body dissociation of isoxazole following double photoionization – an experimental PEPIPICO and theoretical DFT and MP2 study
PublicationThe dissociative double photoionization of isoxazole molecules has been investigated experimentally and theoretically. The experiment has been carried out in the 27.5–36 eV photon energy range using vacuum ultraviolet (VUV) synchrotron radiation excitation combined with ion time-of-flight (TOF) spectrometry and photoelectron–photoion–photoion coincidence (PEPIPICO) technique. Five wellresolved two-body dissociation channels have...
-
Lagrangian model of an isolated dc-dc converter with a 3-phase medium frequency transformer accounting magnetic cross saturation
PublicationThis article presents a nonlinear equivalent circuit model of an isolated dc-dc converter with a 3-phase medium frequency transformer. The model takes into account the magnetic cross saturation of the 3-phase core-type magnetic circuit. The model is suitable in detailed electromagnetic transient simulations of power systems involving isolated dc-dc converters. The model is developed using the Lagrange energy method. It involves...
-
Determination of Butyltin Species in Sea Water Samples Using Solid Phase Extraction Followed by Liquid Chromatography - Tandem Mass Spectrometry
PublicationReverse phase liquid chromatography (RP-HPLC)-electrospray ionization-tandem mass spectrometry (ESI-MS-MS) was evaluated for the analysis of TBT using solid phase extraction as sample preparation method. TBT was extracted from acidified water samples (spiked with tripropyltin as internal standard) using reversed phase polymeric Strata-X cartridges. Analytes were eluted from cartridges using acetonitrile-water mixture and the volume...
-
Microbiological Survey in Two Arctic Fjords: Total Bacterial Number and Biomass Comparison of Hornsund and Kongsfjorden
PublicationTwo microbiological parameters: total bacterial number (TBN) and biomass (BBM) were studied in two Arctic fjords: Hornsund and Kongsfjorden. Samples were collected from three sampling points in each fjord, from various water depth layers: from the surface to 75 m depth. Total bacterial number and biomass were examined using the DAPI staining and direct count method. The greater amount of bacteria, as well as highest bacterial biomass...
-
Microbiological Survey in Two Arctic Fjords: Total Bacterial Number and Biomass Comparison of Hornsund and Kongsfjorden
PublicationTwo microbiological parameters: total bacterial number (TBN) and biomass (BBM) were studied in two Arctic fjords: Hornsund and Kongsfjorden. Samples were collected from three sampling points in each fjord, from various water depth layers: from the surface to 75 m depth. Total bacterial number and biomass were examined using the DAPI staining and direct count method. The greater amount of bacteria, as well as highest bacterial biomass...
-
Simulation of the Remanence Influence on the Transient States of the Single-Phase Transformer Including Feedback Preisach Model
PublicationThis paper presents the results of the experimental and simulation investigation concerning the influence of remanence in the core of a single-phase transformer at the no-load transient state. Experimental studies consisted of the discharge of the capacitor through the primary winding at several different values of the residual magnetic flux. The paper presents a model of the transformer test system, taking into account the magnetic...
-
Two-Stage Identification of Locally Stationary Autoregressive Processes and its Application to the Parametric Spectrum Estimation
PublicationThe problem of identification of a nonstationary autoregressive process with unknown, and possibly time-varying, rate of parameter changes, is considered and solved using the parallel estimation approach. The proposed two-stage estimation scheme, which combines the local estimation approach with the basis function one, offers both quantitative and qualitative improvements compared with the currently used single-stage methods.
-
Soft modes of the dielectric response in the twist–bend nematic phase and identification of the transition to a nematic splay bend phase in the CBC7CB dimer
Publication -
Two‐functional μBIST for Testing and Self‐Diagnosis of Analog Circuits in Electronic Embedded Systems
PublicationThe paper concerns the testing of analog circuits and blocks in mixed‐signal Electronic Embedded Systems (EESs), using the Built‐in Self‐Test (BIST) technique. An integrated, two‐functional, embedded microtester (μBIST) based on reuse of signal blocks already present in an EES, such as microprocessors, memories, ADCs, DACs, is presented. The novelty of the μBIST solution is its extended functionality. It can perform 2 testing functions:...
-
Effect of irradiation intensity and initial pollutant concentration on gas phase photocatalytic activity of TiO2 nanotube arrays
PublicationWell-organized TiO2 nanotube arrays were fabricated via one-step anodization process. The as-prepared TiO2 nanotubes were characterized by X-ray powder diffractometry (XRD), X-ray photoelectron spectroscopy (XPS), diffuse reflectance spectroscopy (DRS) and scanning electron microscopy (SEM). Photocatalytic activity of obtained photocatalyst was studied in reaction of toluene degradation in the gas phase using low powered and low...
-
Overview of Metamaterials-Integrated Antennas for Beam Manipulation Applications: The Two Decades of Progress
PublicationMetamaterials (MMs) are synthetic composite structures with superior properties not found in naturally occurring materials. MMs have gained massive attention over the last two decades because of their extraordinary properties, such as negative permittivity and permeability. These materials enable many applications in communication subsystems, especially in the field of antenna design, to enhance gain, bandwidth, and efficiency,...
-
A headspace solid-phase microextraction method development and itsapplication in the determination of volatiles in honeys by gas chromatography
PublicationThe first part of the paper presents the detailed optimisation of all steps of the determination procedureof volatiles from Polish honeys by headspace solid-phase microextraction (HS-SPME) as the sample preparationmethod and gas chromatography/mass spectrometry (GC-MS) as the method of final determination.The methodology of semi-quantative analysis allowed the isolation and identification of volatile fractioncompounds from popular...
-
Isolation of Human Progenitor Epidermal Cells on Collagen Type IV and Analysis of Their Markers with Flow Cytometry and PCR Methods
PublicationEpidermal stem cells, located in the skin, together with keratinocytes are transplanted in regenerative therapies, e.g., for the treatment of burns or other wounds. Here, we describe the protocol of their enzymatic isolation from human skin. It includes separation of the epidermis form the dermis by incubation with dispase followed by cell isolation for epidermis by digestion with trypsin. Cell isolated with this method can be...
-
Porous material-based sorbent coatings in Solid-phase microextraction technique: Recent trends and future perspectives
PublicationThe use of porous materials as sorbents in sample preparation techniques has gained recent scientific attention in the context of developing novel fibers for the Solid-phase microextraction (SPME) technique. SPME requires the appropriate selection of a robust sorbent for successful utilization under variable conditions. A deeper understanding of the nature of newly developed porous SPME coatings and the impact of their structures...
-
Temperature Evolution, Material Flow, and Resulting Mechanical Properties as a Function of Tool Geometry during Friction Stir Welding of AA6082
PublicationThe friction stir welding process was simulated for joining AA6082 aluminum alloy with the use of the computational fluid dynamics method. Two different tool geometries were used—a tapered cylindrical pin (simple pin) and a hexagonal pin with grooves (complex pin). The analysis of the simulations performed was discussed in terms of temperature evolution during the process, total heat input, residual stresses and material flow....
-
SONIC - Self-optimizing narrowband interference canceler: comparison of two frequency tracking strategies
PublicationThis paper presents a new approach to rejection of complex-valued sinusoidal disturbances acting at the output of a discrete-time linear stable plant with unknown and possibly time-varying dynamics. It is assumed that both the instantaneous frequency of the sinusoidal disturbance and its amplitude may be slowly varying with time and that the output signal is contaminated with wideband measurement noise. The proposed disturbance...
-
Comparison of Two Nonlinear Predictive Control Algorithms for Dissolved Oxygen Tracking Problem at WWTP
PublicationThe wastewater treatment plant is classified as a complex system, due to its nonlinear dynamics, large uncertainty of disturbance inputs, multiple time scales in the internal process dynamics, and multivariable structure. The aeration process, in turn, is an important and expensive part of wastewater treatment plant operation. All operating parameters of the aeration in biological processes are to be precisely controlled to provide...
-
Effective Permeability of Multi Air Gap Ferrite Core 3-Phase Medium Frequency Transformer in Isolated DC-DC Converters
PublicationThe magnetizing inductance of the medium frequency transformer (MFT) impacts the performance of the isolated dc-dc power converters. The ferrite material is considered for high power transformers but it requires an assembly of type “I” cores resulting in a multi air gap structure of the magnetic core. The authors claim that the multiple air gaps are randomly distributed and that the average air gap length is unpredictable at the...
-
Diverse roles, advantages and importance of deep eutectic solvents application in solid and liquid-phase microextraction techniques – A review
PublicationDeep eutectic solvents (DESs) are an emerging class of promising green solvents used as an alternative to traditional organic solvents in various scientific fields. The high biodegradability, biocompatibility, eco-friendliness, tunable properties, and presence of active groups in DESs make them the preferred solvent in a variety of solid- and liquid-phase microextraction techniques. Aside from these benefits, the use of DESs in...
-
Triplet–Triplet Annihilation Upconverting Liposomes: Mechanistic Insights into the Role of Membranes in Two-Dimensional TTA-UC
PublicationTriplet−triplet annihilation upconversion (TTA-UC) implemented in nanoparticle assemblies is of emerging interest in biomedical applications, including in drug delivery and imaging. As it is a bimolecular process, ensuring sufficient mobility of the sensitizer and annihilator to facilitate effective collision in the nanoparticle is key. Liposomes can provide the benefits of two-dimensional confinement and condensed concentration...
-
Modified SPWM Technique with Zero-Sequence Voltage Injection for a Five-Phase, Three-Level NPC Inverter
PublicationThis article presents a modified sinusoidal pulse-width modulation (SPWM) scheme for a five-phase, three-level neutral-point-clamped inverter. The modulation scheme deploys a modified min–max function to inject the zero-sequence components into the reference modulating signals; hence enabling the effective utilization of the DC-link voltage. Balanced split-input DC-link voltages were achieved through further incorporation of adjustable...
-
Novel Family of Single-Phase Modified Impedance-Source Buck-Boost Multilevel Inverters With Reduced Switch Count
Publicationhis paper describes novel single-phase solutions with increased inverter voltage levels derived by means of a nonstandard inverter configuration and impedance source networks. Operation principles based on special modulation techniques are presented. Detailed component design guidelines along with simulation and experimental verification are also provided. Possible application fields are discussed, as well as advantages and disadvantages....
-
Inline Microstrip Bandpass Filter With Two Transmission Zeros and Increased Order Using Spurious Resonance of Frequency-Dependent Inverter
PublicationA design method for a class of fourth-order inline microstrip bandpass filter with two transmission zeros and 20% fractional bandwidth is presented. The filter consists of two quarter-wavelength transmission-line resonators coupled by a frequency-dependent inverter. The inverter is composed of two open-ended stubs that are connected by an interdigital capacitor and introduces two poles and two transmission zeros in the filter response....
-
Application of magnetic nanoparticles for magnetic solid-phase extraction in preparing biological, environmental and food samples
PublicationThe need to obtain meaningful results as the basis for determining the content of trace amounts of analytes has become the driving force behind the development of modern analytical techniques, including sample-preparation techniques, such as solid-phase extraction (SPE). Recently, great interest was aroused in the use of magnetic nanoparticles (MNPs) in SPE. These materials exhibit high selectivity, and, in small amounts, can provide...
-
Effectiveness of toluene separation from gas phase using supported ammonium ionic liquid membrane
PublicationAmmonium ionic liquids (ILs) are relatively cheap in synthesis and environmentally benign and despite that they have been very rarely used in gas separation. In this research we used several ammonium ILs as liquid membranes for removal of residual toluene from gas phase. Ionic liquids used in this study were composed of bis(trifluoromethylsulfonyl)imide anion [Tf2N] and trimethylbutylammonium [N1114], trietylbutylammonium [N2224],...