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Search results for: THIN FILM MICROEXTRACTION
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Improvement of Thrust Bearing Calculation Considering the Convectional Heating within the Space between the Pads
PublicationA modern thrust bearing tool is used to estimate the behavior of tilting pad thrust bearings not only in the oil film between pad and rotating collar, but also in the space between the pads. The oil flow in the space significantly influences the oil film inlet temperature and the heating of pad and collar. For that reason, it is necessary to define an oil mixing model for the space between the pads. In the bearing tool, the solutions...
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Simultaneous grouping and ranking with combination of SOM and TOPSIS for selection of preferable analytical procedure for furan determination in food
PublicationNovel methodology for grouping and ranking with application of self-organizing maps and multicriteria decision analysis is presented. The dataset consists of 22 objects that are analytical procedures applied to furan determination in food samples. They are described by 10 variables, referred to their analytical performance, environmental and economic aspects. Multivariate statistics analysis allows to limit the amount of input...
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The importance of individual spray properties in performance improvement of a urea-SCR system employing flash-boiling injection
PublicationThe appropriate mixing of a urea–water solution (UWS) with exhaust gases in a selective catalytic reduction system is crucial to efficiently reduce nitrogen oxides and diminish the deposition of liquid wall film. One of the methods to enhance the mixing of the UWS with the exhaust gases is a flash-boiling injection. Its positive effect has been linked with a reduced Sauter mean diameter (SMD) and improved evaporation, but the...
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Evaluation of polycaprolactone as a new sorbent coating for determination of polar organic compounds in water samples using membrane–SPME
PublicationCommercially available solid-phase microextraction fibers used for isolation of polar analytes are based on the adsorption phenomenon. In consequence, typical limitations bonded with analytes displacement and matrix effects are very frequent. In the present study, alternative solution is described. Polycaprolactone (PCL) was used for the first time as sorbent to isolate polar organic compounds from water samples using the membrane–solid-phase...
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Pomorskie drogi ku Niepodległej
EventsPolitechnika Otwarta zaprasza na premierowy pokaz filmu Jana Butowskiego pt. „Pomorskie drogi ku Niepodległej”. Poznamy sylwetki bohaterów, miejsca i wydarzenia, które odegrały znaczącą rolę na drodze ku niepodległości.
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The low coherence Fabry-Pérot interferometer with diamond and ZnO layers
PublicationThe authors present a fiber-optic Fabry-Pérot interferometer built with the application of diamond and zinc oxide (ZnO) thin layers. Thin ZnO films were deposited on the tip of a standard telecommunication single-mode optical fiber (SMF- 28) while the diamond layer was grown on the plate of silicon substrate. Investigated ZnO layers were fabricated by atomic layer deposition (ALD) and the diamond films were deposited using Microwave...
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Spectroscopic Study of Plasma Polymerized a-C:H Films Deposited by a Dielectric Barrier Discharge
PublicationPlasma polymerized a-C:H thin films have been deposited on Si (100) and aluminum coated glass substrates by a dielectric barrier discharge (DBD) operated at medium pressure using C2Hm/Ar (m = 2, 4, 6) gas mixtures. The deposited films were characterized by Fourier transform infrared reflection absorption spectroscopy (FT-IRRAS), Raman spectroscopy, and ellipsometry. FT-IRRAS revealed the presence of sp3 and sp2 C–H stretching and...
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Wide-field magnetometry using nitrogen-vacancy color centers with randomly oriented micro-diamonds
PublicationMagnetometry with nitrogen-vacancy (NV) color centers in diamond has gained significant interest among researchers in recent years. Absolute knowledge of the three-dimensional orientation of the magnetic field is necessary for many applications. Conventional magnetometry measurements are usually performed with NV ensembles in a bulk diamond with a thin NV layer or a scanning probe in the form of a diamond tip, which requires a...
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Determination of the substances potentially allergenic in water
PublicationPersonal care chemicals are continuously released into environment through domestic and industrial wastewater, causing adverse effects on human health. Their presence can be detected in different environmental compartments. A group of chemicals included in most personal care products are the allergen fragrances. In the present work, simple and rapid methodology based on ultrasound-assisted emulsification-microextraction (USAEME)...
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Study of the Influence of Heat Convection Coefficient on Predicted Performance of a Large Tilting-Pad Thrust Bearing
PublicationPart of the heat generated by the shearing of the lubricating film during operation of a hydrodynamic bearing is transferred to the bearing components. In the case of the pad, which is usually fully submerged in the lubricating oil, heat is further transferred at the pad free walls to the oil by convection. This mechanism causes a thermal gradient in a pad and, consequently, its thermal deflection. In large hydrodynamic thrust...
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Conducting Polymer Microelectrodes Anchored to Hydrogel Films
PublicationArtykuł prezentuje wytwarzanie organicznych hydrożeli z mikroelektrodami poli(3,4-ethylenedioxythiophene, PEDOT), które wykazują obniżoną rezystywność 100 Ω/□. Proces przygotowania rozpoczyna się elektroosadzania przewodzącego PEDOT (ok. 20 S/cm) na mikroelektrodach Pt. Elektrolityczne wiąże się film PEDOT z hydrożelem. Tak wytworzona struktura jest odrywana elektrycznie pd podłoża.
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A 3D-FEM mesh technique for fast analysis of waveguide problems containing rotatable tuning elements
PublicationIn this paper a meshing technique for 3D Finite Element Method is presented. It allows for fast analysis and optimization of the waveguide structures, which contain rotatable tuning elements. In the proposed procedure a thin layer of varying cylindrical mesh buffer is introduced in order to reuse unchanged mesh and FEM matrices in the rest of the domain.
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Photocatalytic degradation of acetaldehyde in high temperature reaction chamber
Open Research DataThis dataset contains chromatograms recorded during the decomposition of acetaldehyde in a high-temperature reaction chamber under UV irradiation using TiO2 (titanium dioxide) as photocatalysts. It includes data on the influence of flow rate, TiO2 (titanium dioxide) filling the entire reactor, a thin layer of TiO2 (titanium dioxide) supported on KBr...
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Nanosorbents as Materials for Extraction Processes of Environmental Contaminants and Others
PublicationThe aim of this work focuses on the application of nanomaterials (NMs) in different sorp- tive extraction techniques for the analysis of organic contaminants from environmental samples of distinct matrix compositions. Without any doubt, the integration of specific NMs such as carbona- ceous nanomaterials, magnetic nanoparticles (MNPs), metal–organic frameworks (MOFs), silica na- noparticles, and ion-imprinted NPs with so lid-phase...
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In-situ monitoring of electropolymerization processes at boron-doped diamond electrodes by Mach-Zehnder interferometer
PublicationIn this work, the Mach-Zehnder interferometer was designed to monitor the electrochemical processes conducted at boron-doped diamond electrode surface. The diamond electrodes were synthesized via Microwave Plasma-Assisted Chemical Vapor Deposition on optical grade quartz glass. The achieved transmittance in working are of diamond electrodes reached 55 %. A cage system-based Mach-Zehnder interferometer was used which allowed the...
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Titania Nanotubes/Hydroxyapatite Nanocomposites Produced with the Use of the Atomic Layer Deposition Technique: Estimation of Bioactivity and Nanomechanical Properties
PublicationTitanium dioxide nanotubes/hydroxyapatite nanocomposites were produced on a titanium alloy (Ti6Al4V/TNT/HA) and studied as a biocompatible coating for an implant surface modification. As a novel approach for this type of nanocomposite fabrication, the atomic layer deposition (ALD) method with an extremely low number of cycles was used to enrich titania nanotubes (TNT) with a very thin hydroxyapatite coating. X-ray diffraction (XRD)...
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SEM inwestigation of the silver nanostructures
Open Research DataSilver thin films with a thickness of 1nm, 3nm, 5nm, 7nm and 9nm were deposited by a table-top magnetron sputtering unit in a pure argon plasma from a high-purity silver target. Silicon wafers was used as a substrates. As-deposired films were annealed in Ar atmosphere at 550 Celsius degree for 15 minutes.As a result of annealing, Ag nanostructures formed...
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Multicriteria decision analysis in ranking of analytical procedures for aldrin determination in water
PublicationThe study presents the possibility of multi-criteria decision analysis (MCDA) application when choosing analytical procedures with low environmental impact. A type of MCDA, Preference Ranking Organization Method for Enrichment Evaluations (PROMETHEE), was chosen as versatile tool that meets all the analytical chemists – decision makers requirements. Twenty five analytical procedures for aldrin determination in water samples (as...
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‘Green’ multi - residue methods for the determination of high importance currently used pesticides in environmental samples
PublicationThe purpose of the research has been to develop and apply ‘green’ analytical methodologies to control and monitor the level of currently used pesticides from different chemical groups in aqueous samples. For extraction of analytes solid - phase microextraction (SPME) and dispersive liquid - liquid microextraction (DLLME) have been applied and compared. For SPME, commonly used materials for coating fibers include: polydimethylsiloxane...
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Experimental data of galvanic electric cells measurements
Open Research DataInternal temperature of an electric cell can be measured and monitored using microsphere-based fiber-optic sensors with thin ALD ZnO coating. Their compact size will allow to integrate them easily and effectively within the electric cells. Utilization of presented sensors allows to detect, in real time, damages to the structure of the sensor head that...
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Wideband crossover structure with double ring resonators
PublicationThe structure of a four-port microstrip crossover is presented. The device is composed of two ring resonators, one circular and one built from meander lines, connected by four straight lines. The equivalent circuit model of the crossover is derived. The structure is designed on thin and flexible substrate to allow it to bend. The possibility of applying the device on curved surfaces is tested experimentally.
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Simulation investigation of perovskite-based solar cells
PublicationThree models of thin-layer lead-halide perovskite solar cells with different electron-transport layers (TiO2,SnO2,ZnO) were investigatedby the simulation method. The perovskite layer thickness was optimized for all the systems. The analysis of the standard photovoltaic cell performanceparameters at various operating temperatures was performed. The best performance was achieved for the system with theSnO2conductive layer.
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Developments in Green Chromatography
PublicationGreen analytical chemistry is a widely recognized concept that has led to the development of new analytical methods with reduced environmental impact and minimized analyst occupational exposure. Achievements include the development of microextraction, ultrasound-assisted extraction (UAE), and microwave-assisted extraction (MAE) techniques. Research towards greener separation processes focuses on the elimination of toxic solvents...
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ZnO coated fiber optic microsphere sensor for the enhanced refractive index sensing
PublicationOptical fiber-based sensors are expected to become key components in the control of industrial processes,and the tuning and the enhancement of their sensing properties are crucial for the further developmentof this technology. Atomic Layer Deposition (ALD), a vapor phase technique allowing for the deposition ofconformal thin films, is particularly suited for the deposition of controllable thin films on challenging sub-strates....
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COMPARISON OF HEAT TRANSFER CHARACTERISTICS IN SURFACE COOLING WITH BOILING MICROJETS OF WATER, ETHANOL AND HFE7100
PublicationThe basis of microjet technology is to produce laminar jets which when impinging the surface have a very high kinetic energy at the stagnation point. Boundary layer is not formed in those conditions, while the area of film cooling has a very high turbulence resulting from a very high heat transfer coefficient. Applied technology of jet production can result with the size of jets ranging from 20 to 500μm in breadth and 20 to 100μm...
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Boron-Doped Diamond/GaN Heterojunction—The Influence of the Low-Temperature Deposition
PublicationWe report a method of growing a boron-doped diamond film by plasma-assisted chemical vapour deposition utilizing a pre-treatment of GaN substrate to give a high density of nucleation. CVD diamond was deposited on GaN substrate grown epitaxially via the molecular-beam epitaxy process. To obtain a continuous diamond film with the presence of well-developed grains, the GaN substrates are exposed to hydrogen plasma prior to deposition....
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Experimental comparison of the transition speed of a hydrodynamic journal bearing lubricated with oil and magnetorheological fluid
PublicationA journal bearing test bench is used to find the transition speed between the hydrodynamic and mixed lubrication regimes for a modified magnetorheological (MR) fluid. It is shown that the transition speed of the bearing can be reduced by applying a local magnetic field near minimum film when it is lubricated with the MR fluid, and that this will only marginally increase friction. The lubricating performance of the MR fluid is compared...
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Green sample preparation techniques for chromatographic determination of small organic compounds
PublicationAccurate monitoring of the state of the environment requires the introduction of additional isolation and/or preconcentration step prior to the chromatographic determination. In this work the information about novel methodological and instrumental solutions in relation to different variants of microextraction techniques are presented. Attention is focused on analytical procedure and suitable analytical tools for extraction of the...
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Natural/bio-based sorbents as greener extractive materials for endocrine disrupting compounds in samples of different matrix composition
PublicationEndocrine-disrupting compounds (EDCs) are a group of chemicals that interfere with the endocrine system, leading to adverse effects on human health and the environment. Increasing concerns over the EDCs presence in various environmental compartments has driven the search for greener extraction materials. Recently, the use of polymers of natural origin (biopolymers) has been demonstrated to be an effective and promising research...
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Nitrogen dioxide sensing properties of PEDOT polymer films
PublicationThis work presents a simple and fully electrochemical route for the polymerization of poly(3,4-ethylenedioxytiophene) (PEDOT) films for fabricating a NO2 gas sensor prepared by electropolymerization of 3,4-Ethylenedioxythiophene (EDOT) monomer in lithium perchlorate/acetonitrile solution. The main aim of this study is to determine the sensing properties of conductive polymer at elevated temperatures. The effects of the humidity,...
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Nowe rozwiązania metodyczne i techniczne w zakresie techniki mikroekstrakcji do fazy stracjonarnej
PublicationSample preparation has been recognized as a critical step of the analytical process, being even considered as the bottleneck of the overall process. Enrichment of target compounds, transfer of the analytes into a solvent compatible with the analytical instrumentation, minimization of potential interferences, and efficient sample clean-up, are among the main aims of sample preparation techniques. In this regard, liquid-liquid extraction...
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Engineering Au nanoparticle arrays on SiO2 glass by pulsed UV laser irradiation
PublicationWe study semi-regular arrays of Au nanoparticles (NP) obtained via UV laser irradiation of thin Au films on glass substrate. The NP structures are prepared from films of a thickness up to 60 nm produced by discharge sputtering or pulsed laser deposition, and annealed by nanosecond laser pulses at 266 or 308 nm, respectively, at fluencies in the range of 60-410 mJ/cm2. For the rare- and close-packed NP structures, consistent description...
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Capacity of Surface Production of Band Sawing in Manufacture of Oak Floor Upper Layers
PublicationThin lamellae, corresponding to the layer components of structural glued members, i.e., 2-ply or 3-ply glued flooring, can be manufactured in re-sawing operations of kiln-dried wood blocks or in wet technologies, which currently seem to be more common because of the shorter drying time. The re-sawing process in wet technology is conducted on dedicated thin-cutting band sawing machines with stellite-tipped band saws. The goal of...
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Production of new non-matrix reference material of ethene
PublicationThe main objective of the research is to produce new non-matrix reference materials of ethene. The study are based on thermal decomposition of surface compound chemically bonded with the surface of glass fibers coated with thin layer of aluminum. Positivehomogeneity test, stability test and organization of inter-laboratory comparison are leading to find new non-matrix reference materials which are indispensable tools in the analysis...
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Modeling of Composite Shells in 6-Parameter Nonlinear Theory with Drilling Degree of Freedom
PublicationWithin the framework of a 6-parameter nonlinear shell theory, with strain measures of Cosserat type, constitutive relations are proposed for thin elastic composite shells. The material law is expressed in terms of five engineering constants of classical anisotropic continuum plus an additional parameter accounting for drilling stiffness. The theory allows for unlimited displacements and rotations. A number of examples are presented...
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Effect of power frequency on the stress state of disc actuator
PublicationThis paper presents the concept of determining the optimum frequency of coil supply in inductive-dynamic drive. As a criterion to obtain the sought frequency, the smallest value of reduced stress in the disc was assumed while maintaining the desired dynamics. The disc stress is determined on the basis of solution of vibrating thin plate equation. Magnetic pressure acting on the disc is obtained from a hybrid circumferentially-field...
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Studies on optical transmittance of boron-doped nanocrystalline diamond films
PublicationThickness is one of the most important parameters in many applications using thin layers. This article describes thickness determination of a boron-doped nanocrystalline diamond (NCD) grown on fused silica glass. A spectroscopic measurement system has been used. A high refractive index (2.3 at 550nm) was achieved for NCD films. The thickness of NCD samples has been determined from the transmission spectrum.
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Investigation of the thermal effects in water-lubricated journal bearings with axial grooves
PublicationWater-lubricated hydrodynamic journal bearings are frequently applied as stern tube bearings due to their advantages over other bearing types. They are environmentally friendly, can operate without sealings and in conditions of low friction losses. The most popular are bearings with open axial grooves, which require, for proper operation, forced axial flow of the lubricating water. Correctly designed and operated stern tube bearings...
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Efektywność skrępowania betonu w grubościennych słupach typu Concrete-Filled Steel Tube o przekroju kołowym
PublicationW słupach typu CFST w stanie granicznym dochodzi do zwiększenia wytrzymałości betonu rdzenia na skutek jego skrępowania. Zaistnienie tego zjawiska zależy od wielu czynników. Jednym z najważniejszych z nich jest sztywność obwodowa płaszcza stalowego. Jej wpływ na efektywność wzrostu wytrzymałości betonu rdzenia przebadano eksperymentalnie na grupie 48 grubościennych słupów CFST. Wykazano, że nadmierne zwiększanie grubości płaszcza...
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Determination of terpene profiles in potential superfruits
PublicationThe aim of this work was to characterize and compare the profiles of volatile terpenes in four potential superfruits. These profiles were determined using headspace solid-phase microextraction coupled with comprehensive two-dimensional gas chromatography linked to time-of-flight mass spectrometry. The proposed technique allowed the separation and identification of 79 terpenes present in cape gooseberry, crabapple, cherry silver...
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Determination of Terpene Profile in Cape gooseberry (Physalis peruviana L.) with Use of HS-SPME/GCxGC-TOFMS Method
PublicationFresh fruits and products made of them, especially fruit juice, provide the basic energetic substances (simple and complex sugars) and are a source of health beneficial vitamins, macro and microelements, antioxidants and compounds which are classified together with essential oils (for example terpenes), which positively affect human s health. The terpenes profile of cape gooseberry was determined by headspace solid--phase microextraction...
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Miniaturized Solid Phase Extraction techniques for different kind of pollutants analysis: State of the art and future perspectives – PART 1
PublicationSolid Phase Extraction (SPE) has been practiced in a modern form for more than half a century. It was constantly developing, driven by the analysts needs. These needs are coming from the importance to select an appropriate analytical method, which should have satisfactory accuracy, precision and sensitivity. In the case of sorbent-based microextraction techniques, the choice of miniaturized variants that meet these requirements...
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Reduction of parasitic pitch variations in archival musical recordings
PublicationA new method for reducing parasitic pitch variations in archival audio recordings is presented. The method is intended for analyzing movie soundtracks recorded in optical films. It utilizes image processing for calculating and reducing effects of tape shrinkage being one of the main reasons for parasitic pitch variations in audio accompanying moving images. As long as the film tape characteristics are known the new method can be...
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Elctrochemical oxidation and corrosion resistance of the Ti13Nb13Zr alloy
PublicationThis paper presents the results of oxidation and corrosion tests carried out on titanium alloy Ti13Nb13Zr. The oxide film was prepared by electrochemical environment 2M H3PO4 for 30 min and 1 h, at a constant voltage 40V. The tests of corrosion resistance were performed by potentiostatic method in Ringer's solution at different pH values: 7, 5 and 3. The change in an appearance of surface and the increase in corrosion resistance...
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A SEARCH OF AN INDUCER GEOMETRY THAT IS BENEFICIAL FOR LIFTING PARAMETERS OF A LIFTED OBJECT OF A SELECTED SHAPE
PublicationThe literature describes acoustic levitation phenomena with the utilization of air squeeze film between the vibrating inducer and the lifted object. The objective of the study is to determine the shape of the inducer with vibration characteristics that would allow the levitation of an object of the assumed geometry. In this paper, the influence of the dimension ratio of the inducer on the frequency of the first mode of vibration...
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Distance measurement with the low coherent interferometer with silver mirror (the source wavelegth 1310 nm) - 0 um (serie 2)
Open Research DataThe obtained data was acquired by the interferometric fiber-optic sensor of distance. The setup was constructed of a broadband light source working at the central wavelength of 1310 nm, an optical spectrum analyzer, and a fiber-optic 2x1 coupler (with the power split 50:50). All elements were connected by standard single-mode optical fibers. The measurement...
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Distance measurement with the low coherent interferometer with silver mirror (the source wavelegth 1310 nm) - 40 um (serie 2)
Open Research DataThe obtained data was acquired by the interferometric fiber-optic sensor of distance. The setup was constructed of a broadband light source working at the central wavelength of 1310 nm, an optical spectrum analyzer, and a fiber-optic 2x1 coupler (with the power split 50:50). All elements were connected by standard single-mode optical fibers. The measurement...
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Distance measurement with the low coherent interferometer with silver mirror (the source wavelegth 1310 nm) - 30 um (serie 2)
Open Research DataThe obtained data was acquired by the interferometric fiber-optic sensor of distance. The setup was constructed of a broadband light source working at the central wavelength of 1310 nm, an optical spectrum analyzer, and a fiber-optic 2x1 coupler (with the power split 50:50). All elements were connected by standard single-mode optical fibers. The measurement...
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Distance measurement with the low coherent interferometer with silver mirror (the source wavelegth 1310 nm) - 200 um (serie 2)
Open Research DataThe obtained data was acquired by the interferometric fiber-optic sensor of distance. The setup was constructed of a broadband light source working at the central wavelength of 1310 nm, an optical spectrum analyzer, and a fiber-optic 2x1 coupler (with the power split 50:50). All elements were connected by standard single-mode optical fibers. The measurement...
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Distance measurement with the low coherent interferometer with silver mirror (the source wavelegth 1310 nm) - 20 um (serie 1)
Open Research DataThe obtained data was acquired by the interferometric fiber-optic sensor of distance. The setup was constructed of a broadband light source working at the central wavelength of 1310 nm, an optical spectrum analyzer, and a fiber-optic 2x1 coupler (with the power split 50:50). All elements were connected by standard single-mode optical fibers. The measurement...