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Search results for: optical networks
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Optical properties of the chemotherapy drugs used in the central nervous system lymphoma therapy: monitoring drug delivery
PublicationOur aim is to optically monitor the delivery of the chemotherapy drugs for brain tumours, particularly used in the central nervous system (CNS) lymphoma therapy. In vivo monitoring would help to optimize the treatment and avoiding unnecessary medications. Moreover, it would be beneficial to be able to measure which of the multi-regimen drugs actually do penetrate and how well into the brain tissue. There exist several potential...
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1D portable optical coherence tomography system
Publication—Imaging methods are an expanding branch of technology, which involves data acquisition and analysis of images for research and diagnostics. This paper has been devoted to the description of the optical design for a one-dimensional, portable optical coherence tomography (OCT) system. The Mach-Zehnder interferometer has been designed in the presented study. The description of the construction and applied hardware solutions have...
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Investigation of H2:CH4 plasma composition by means of spatially resolved optical spectroscopy
PublicationThe system based on spatially resolved optical emission spectroscopy dedicated for in situ diagnostics of plasma assisted CVD processes is presented in this paper. Measurement system coupled with chemical vapour deposition chamber by dedicated fiber-optic paths enables investigation of spatial distribution of species densities (Hx, H+, CH, CH+) during chemical vapour deposition process. Experiments were performed for a various...
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Nanoparticles displacement analysis using optical coherence tomography
PublicationOptical coherence tomography (OCT) is a versatile optical method for cross-sectional and 3D imaging of biological and non-biological objects. Here we are going to present the application of polarization sensitive spectroscopic OCT system (PS-SOCT) for quantitative measurements of materials containing nanoparticles. The PS-SOCT combines the polarization sensitive analysis with time-frequency analysis. In this contribution the benefits...
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Detection system for optical coherence tomography: Czerny-Turner spectrometer
PublicationResearch methods based on spectral analysis have powerful impact on development in many field of science. Signal spectrum can be a source of useful and important data. It enables to obtain information about physical and chemical properties of tested materials. This paper has been devoted to describe optical design for high resolution spectrometer, which is significant element of optical coherence tomography (OCT) systems. Designed...
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Functional fluorine-doped tin oxide coating for opto-electrochemical label-free biosensors
PublicationSensors operating in multiple domains, such as optical and electrochemical, offer properties making biosensing more effective than those working in a single domain. To combine such domains in one sensing device, materials offering a certain set of properties are required. Fluorine-doped tin oxide (FTO) thin film is discussed in this work as functional optically for guiding lossy modes and simultaneously electrochemically, i.e....
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Improved surface coverage of an optical fibre with nanocrystalline diamond by the application of dip-coating seeding
PublicationGrowth processes of diamond thin films on the fused silica optical fibres (10 cm in length) were investigated at various temperatures. Fused silica pre-treatment by dip-coating in a dispersion consisting of detonation nanodiamond (DND) in dimethyl sulfoxide (DMSO) with polyvinyl alcohol (PVA) was applied. Nanocrystalline diamond (NCD) films were deposited on the fibres using the microwave plasma assisted chemical vapour deposition...
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MONTE CARLO MODELING OF OPTICAL SENSOR FOR POST-OPERATIVE FREE FLAP MONITORING
PublicationAfter a preliminary study of the currently employed methods in vitality monitoring of the tissue flaps (TRAM, DIEP, SIEA), a usefulness of optical techniques is discussed. It seems that one of the most promising in monitoring tissue flaps blood flow is a near infrared spectrometry (NIRS). However, a special design of a measurement sensor has to be developed. First, basing on the literature study an optical “window” is characterized....
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Application of fiber optic sensors using Machine Learning algorithms for temperature measurement of lithium-ion batteries
PublicationOptical fiber sensorsusing low-coherence interferometry require processing ofthe output spectrum or interferogramto quickly and accurately determine the instantaneous value of the measured quantity, such as temperature.Methods based on machine learning are a good candidate for this application. The application of four such methods in an optical fiber temperature sensoris demonstrated.Using aZnO-coated...
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Measurement of complex refractive index of human blood by low-coherence interferometry
PublicationIn this article, the usefulness of the optical technique for measurements of blood complex refractive index has been examined. Measurement of optical properties of human blood is difficult to perform because of its nonuniform nature. However, results of my investigation have shown the usefulness of low-coherencei nterferometry for measurement complex refractive index of human blood. Furthermore, mathematical analysis of spectrum...
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Vibrational Quenching of Optically Pumped Carbon Dimer Anions
PublicationCareful control of quantum states is a gateway to research in many areas of science such as quantum information, quantum-controlled chemistry, and astrophysical processes. Precise optical control of molecular ions remains a challenge due to the scarcity of suitable level schemes, and direct laser cooling has not yet been achieved for either positive or negative molecular ions. Using a cryogenic wire trap, we show how the internal...
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Optical profilometer
PublicationThe profilometry plays a huge role in the most fields of science and technology. It allows to measure the profile of the surface with high-resolution. This technique is used in the fields like optic, electronic, medicine, automotive, and much more. The aim of the current work was to design and build optical profilometer based on the interference phenomena. The developed device has been working with He-Ne laser (632.8 nm). The optical...
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Temperature Coefficient of Electronic Polarizability in Thin Polymer Films Deposited on Si and SiO2 Substrates Determined via Spectroscopic Ellipsometry
PublicationEllipsometry is widely used to determine the thermo-optical properties of thin polymer films. However, if the thermo-optic coefficient (TOC) and the linear thermal expansion coefficient (LTEC) are to be used to determine the temperature coefficient of electronic polarizability (TCEP) in thin polymer films, their values must be determined with the greatest possible accuracy, as both have the opposite effect. In this article,...
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The realization of ASON/GMPLS control plane
PublicationASON (Automatic Switched Optical Network) is a concept of optical network recommended in G.8080/Y.1304 by ITU-T. Control Plane of this network could be based on GMPLS (Generalized Multi-Protocol Label Switching) protocols like RSVP-TE, OSPF-TE, LMP. This solution is named ASON/GMPLS. In this chapter we present the control plane problems and proposes ASON/GMPLS network realization that are tested on testbed consists of three and...
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Application of Thin ZnO ALD Layers in Fiber-Optic Fabry-Pérot Sensing Interferometers
PublicationIn this paper we investigated the response of a fiber-optic Fabry-Pérot sensing interferometer with thin ZnO layers deposited on the end faces of the optical fibers forming the cavity. Standard telecommunication single-mode optical fiber (SMF-28) segments were used with the thin ZnO layers deposited by Atomic Layer Deposition (ALD). Measurements were performed with the interferometer illuminated by two broadband sources operating...
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Electrochemically directed biofunctionalization of a lossy-mode resonance optical fiber sensor
PublicationIn this work, we present a direct electrochemical biofunctionalization of an indium-tin-oxide-coated lossy-mode resonance optical fiber sensor. The functionalization using a biotin derivative was performed by cyclic voltammetry in a 10 mM biotin hydrazide solution. All stages of the experiment were simultaneously verified with optical and electrochemical techniques. Performed measurements indicate the presence of a poly-biotin...
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Ab-initio study of electrical and optical properties of allylamine
PublicationThe Density functional theory is one of most promising methodology in fast and accurate calculations of electrical and optical properties from the atomic basis. In this paper, we calculate electrical and optical properties of allylamine (2-propen 1- amine) in terms of accuracy and speed of calculations obtained by selection of DFT-1/2 method with ultrasoft Vanderbilt pseudopotentials. Comparison of density of states between...
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Automatic system for optical parameters measurements of biological tissues
PublicationIn this paper a system allowing execution of automatic measurements of optical parameters of scattering materials in an efficient and accurate manner is proposed and described. The system is designed especially for measurements of biological tissues including phantoms, which closely imitate optical characteristics of real tissue. The system has modular construction and is based on the ISEL system, luminance and color meter and...
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Ab-initio study of electrical and optical properties of allylamine
PublicationThe Density functional theory is one of most promising methodology in fast and accurate calculations of electrical and optical properties from the atomic basis. In this paper, we calculate electrical and optical properties of allylamine (2-propen 1- amine) in terms of accuracy and speed of calculations obtained by selection of DFT-1/2 method with ultrasoft Vanderbilt pseudopotentials. Comparison of density of states between molecule...
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Tuning of the plasmon resonance location in Au nanostructures coated with a ultrathin film of Al2O3 – Optical measurements and FDTD simulations
PublicationThe Au nanostructures have been coated with an ultra-thin films of amorphous aluminium oxide. Optical absorption spectra show the influence of the thickness of Al2O3 on plasmon resonance wavelength. The observed red-shift of the resonance location with the increase of the thickness of the Al2O3 film, can be explained by the change in the dielectric function of this film. It allows control of the optical spectra of the coated particles....
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Topological extraordinary optical transmission
PublicationΤhe incumbent technology for bringing light to the nanoscale, the near-field scanning optical microscope, has notoriously small throughput efficiencies of the order of 10^4-10^5 or less. We report on a broadband, topological, unidirectionally guiding structure, not requiring adiabatic tapering and, in principle, enabling near-perfect (∼100%) optical transmission through an unstructured single arbitrarily subdiffraction slit at...
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Study of the optical rotatory of potassium titanyl phosphate using the advanced dual-wavelength polarimetric method
PublicationA dual-wavelength high-accuracy universal polarimeter was applied to the circular birefringence and optical activity measurement in potassium titanyl phosphate (KTP) nonlinear crystal. The experimental setup used two single-mode He-Ne lasers with close wavelengths of 594 and 633 nm as light sources. Measurement has been carried out for two crystal settings in directions of a 45-degree relative angle to the [100] and [010] crystallographic...
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Ellipsometric investigation of nitrogen doped diamond thin films grown in microwave CH4/H2/N2 plasma enhanced chemical vapor deposition
PublicationThe influence of N2 concentration (1%–8%) in CH4/H2/N2 plasma on structure and optical properties of nitrogen doped diamond (NDD) films was investigated. Thickness, roughness, and optical properties of the NDD films in the VIS–NIR range were investigated on the silicon substrates using spectroscopic ellipsometry. The samples exhibited relatively high refractive index (2.6 6 0.25 at 550 nm) and extinction coefficient (0.05 6 0.02...
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An Improved Synthesis of Trisodium (R)-Homocitrate from Citric Acid
PublicationA method of synthesis of trisodium (R)-homocitrate starting from citric acid is reported. The procedure affords the final product of high optical purity with satisfactory yield.
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Chiral-based optical and electrochemical biosensors: Synthesis, classification, mechanisms, nanostructures, and applications
PublicationThis review seeks to collect, summarize, classify and discuss the latest advances in chiral-based optical biosensors. Starting from the identification of chiral molecules, photoluminescence, and electrochemical sensors, applications of chiral structures in biosensing molecules are reviewed. Then, biosensors working on the basis of chirality are classified, followed by summarizing the outcomes of research works on design, synthesis,...
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Fiber optic microsphere with a ZnO thin film for potential application in a refractive index sensor – theoretical study
PublicationOptical fiber sensors of refractive index play an important role in analysis of biological and chemical samples. This work presents a theoretical investigation of spectral response of a fiber optic microsphere with a zinc oxide (ZnO) thin film deposited on the surface and evaluates the prospect of using such a structure for refractive index sensing. A microsphere is fabricated by an optical fiber tapering method on the base of...
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Application of the Fractional Fourier Transform for dispersion compensation in signals from a fiber-based Fabry-Perot interferometer
PublicationOptical methods of measurement do not require contact of a probe and the object under study, and thus have found use in a broad range of applications such as nondestructive testing (NDT), where noninvasive measurement is crucial. Measuring the refractive index of a material can give a valuable insight into its composition. Low‑coherence radiation sources enable measurement of the sample’s properties across a wide spectrum, while...
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Nucleation and growth of CVD diamond on fused silica optical fibres with titanium dioxide interlayer
PublicationNucleation and growth processes of thin diamond films on fused silica optical fibres have been investigated. Fibres were coated with diamond film using microwave plasma enhanced chemical vapour deposition (µPE CVD) system. Since the growth of diamond on the fused silica glass requires high seeding density, two types of glass pre-treatment were applied: titanium dioxide (TiO2) interlayer deposition and sonication in nanodiamond...
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Diamond-based protective layer for optical biosensors
PublicationOptical biosensors have become a powerful alternative to the conventional ways of measurement owing to their great properties, such as high sensitivity, high dynamic range, cost effectiveness and small size. Choice of an optical biosensor's materials is an important factor and impacts the quality of the obtained spectra. Examined biological objects are placed on a cover layer which may react with samples in a chemical, biological...
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Tailoring properties of indium tin oxide thin films for their work in both electrochemical and optical label-free sensing systems
PublicationThis work is devoted to the identification properties of indium tin oxide (ITO) thin films responsible for their possible application in combined optical and electrochemical label-free sensing systems offering enhanced functionalities. Since any post-processing would make it difficult to identify direct relation between deposition parameters and properties of the ITO films, especially when deposition on temperature-sensitive substrates...
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Advanced polarization sensitive analysis in optical coherence tomography
PublicationThe optical coherence tomography (OCT) is an optical imaging method, which is widely applied in variety applications. This technology is used to cross-sectional or surface imaging with high resolution in non-contact and non-destructive way. OCT is very useful in medical applications like ophthalmology, dermatology or dentistry, as well as beyond biomedical fields like stress mapping in polymers or protective coatings defects detection....
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The In-Depth Studies of Pulsed UV Laser-Modified TiO2 Nanotubes: The Influence of Geometry, Crystallinity, and Processing Parameters
PublicationThe laser processing of the titania nanotubes has been investigated in terms of morphology, structure, and optical properties of the obtained material. The length of the nanotubes and crystallinity, as well as the atmosphere of the laser treatment, were taken into account. The degree of changes of the initial geometry of nanotubes were checked by means of scanning electron microscopy, which visualizes both the surface and the cross-section....
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Plasma-Based Deposition and Processing Techniques for Optical Fiber Sensing
PublicationPlasma-based techniques are widely applied for well-controlled deposition, etching or surface functionalization of a number of materials. It is difficult to imagine fabrication of novel microelectronic and optoelectronic devices without using plasma-enhanced deposition of thin films, their selective etching or functionalization of their surfaces for subsequent selective binding of chemical or biological molecules. Depending on...
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Enhanced Eye-Tracking Data: a Dual Sensor System for Smart Glasses Applications
PublicationA technique for the acquisition of an increased number of pupil positions, using a combined sensor consisting of a low-rate camera and a high-rate optical sensor, is presented in this paper. The additional data are provided by the optical movement-detection sensor mounted in close proximity to the eyeball. This proposed solution enables a significant increase in the number of registered fixation points and saccades and can be used...
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Sensors integration in the smart home environment - a proposal to solve the problem with user identification
PublicationIn this preliminary study we, investigate the possibility of user recognition techniques suitable on smart home devices like chairs, beds, aiming for low–power, high accuracy and quick response time. We propose the two well know technique: voice speaker recognition and accelerometer signal from device mounted on the chair, and the third one optical system basing on IR LED transmitter/receiver circuit. The preliminary results proved...
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Investigations of the optical activity of nonlinear crystals by means of dual-wavelength polarimeter
PublicationA dual-wavelength method in high accuracy polarimetry has been successfully tested and applied to measure optical activity (OA) of nonlinear crystals. In proposed polarimetric scheme two neighboring semiconductor laser wavelengths (635 and 650 nm) are used, which increases number of parameters measured simultaneously and improves the data processing. By neglecting dispersion of eigen wave ellipticity in crystals, more efficient...
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Simulating coherent light propagation in a random scattering materials using the perturbation expansion
PublicationMultiple scattering of a coherent light plays important role in the optical metrology. Probably the most important phenomenon caused by multiple scattering are the speckle patterns present in every optical imaging method based on coherent or partially coherent light illumination. In many cases the speckle patterns are considered as an undesired noise. However, they were found useful in various subsurface imaging methods such as...
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Biophotonic low-coherence sensors with boron-doped diamond thin layer
PublicationLow-coherence sensors using Fabry-Perot interferometers are finding new applications in biophotonic sensing, especially due to the rapid technological advances in the development of new materials. In this paper we discuss the possibility of using boron-doped nanodiamond layers to protect mirror in a Fabry-Perot interferometer. A low-coherence sensor using Fabry-Perot interferometer with a boron-doped nanodiamond (B-NCD) thin protective...
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Nanocrystalline CVD Diamond Coatings on Fused Silica Optical Fibres: Optical Properties Study
Publicationpre-treatment by dip coating in two detonation nanodiamond (DND) seeding media has been studied. The DND suspension in ethyl alcohol and dispersion of DND in dimethyl sulfoxide (DMSO) with polyvinyl alcohol (PVA) were chosen for the seeding purpose. The grain size distribution of nanodiamond particles in both seeding media was kept at the same level (approximately 1050 nm). After the seeding nanocrystalline diamond lms were deposited...
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Magnetic switching of Kerker scattering in spherical microresonators
PublicationMagneto-optical materials have become a key tool in functional nanophotonics, mainly due to their ability to offer active tuning between two different operational states in subwavelength structures. In the long-wavelength limit, such states may be considered as the directional forward- and back-scattering operations, due to the interplay between magnetic and electric dipolar modes, which act as equivalent Huygens sources. In this...
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Determination of the refractive index and wavelength‐dependent optical properties of few‐layer CrCl3 within the Fresnel formalism
PublicationBased on previous reports on the optical microscopy contrast of mechanically exfoliated few layer CrCl3 transferred on 285 nmand 270 nmSiO2 on Si(100), we focus on the experimental determination of an effective mean complex refractive index via a fitting analysis based on the Fresnel equations formalism. Accordingly, the layer and wavelength-dependent absorbance and reflectance are calculated. Layer and wavelength-dependent optical...
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Modeling of multi-cavity Fabry-Perot optical fiber sensors
PublicationReflectance characteristics of a two-cavity extrinsic Fabry-Perot optical fiber sensor were investigated using computer modeling. Calculations were performed using a plane wave-based approach, selected for clarity of results. Based on the modeling results, it can be concluded that the two-cavity Fabry-Perot interferometer can be used to measure two different quantities, such as refractive index and temperature, independently. It...
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Optimization of a Fabry-Perot Sensing Interferometer design for an optical fiber sensor of hematocrit level
PublicationContinuous measurement of the hemato crit level in blo o d can p otentially b e p erformed using optical bre sensors. The FabryPerot interferometric sensors are a promising candidate in this application. The most imp ortant step in the design of the sensor is design of the sensing interferometer. Adequate cavity length and high interference contrast are two most imp ortant requirements in this application. The design metho d of...
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Dual-wavelength polarimeter application in investigations of the optical activity of a langasite crystal
PublicationA method of high accuracy polarimetry, which includes optical activity measurements systematic errors, was realized with dual-wavelength polarimeter for two wavelengths of 635 and 650 nm. Simultaneous measurements with neighboring wavelengths significantly improved the data processing, by increasing the amount of data to eliminate the systematic errors. For langasite crystal La3Ga5SiO14 we measured temperature dependence of the...
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Comparing of optical properties and morphology of polyoxadiazoles with CF3 groups
PublicationPurpose: The aim of this paper is to compare optical properties of 4-(1,1,1,3,3,3-hexafluoro-2(-4(-3(4-(5-(4-m-tolyoxy)phenyl)-1,3,4-oxadiazol-2-yl)phenoxy)phenylcarbomyl)phenyl)propan2-yl)-N-methylbenzamide(Oxad 6F-D) and 4-(1,1,1,3,3,3-hexafluoro-2(-4-(4-(4-(5-(4-(p-tolyoxy)phenyl)-1,3,4-oxadiazol-2-yl)phenoxycarbaomyl)phenyl)propan-2-yl)-N-methylbenzamide (Oxad 6F-E).Design/methodology/approach: The Oxad 6F polymer thin films...
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Barium boron aluminum silicate glass system for solid state optical gas sensors
PublicationRecent increasing demand for new eco-friendly materials and for low cost fabrication process for use in optical sensors field, raise concern about alternative materials for this application. We have designed two glass-ceramics compositions from the quaternary ROAl2O3- SiO2-B2O3(R=Ba) alkali-earth aluminum silicate system, labeled B72 and B69, with high refractive index (>1.6), large values of Abbe number (94.0 and 53.0, respectively),...
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Optoelectronic investigation of nanodiamond interactions with human blood
PublicationWe present optoelectronic investigation of in vitro interactions of whole human blood with different nanodiamond biomarkers. Plasmo-chemical modifications of detonation nanodiamond particles gives the possibility for controlling their surface for biological applications. Optical investigations reveal the biological activity of nanodiamonds in blood dependent on its surface termination. We compare different types of nanodiamonds:...
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The finite-difference simulation of x-rays propagation through a system of lenses
PublicationThe propagation of X-ray waves through an optical system consisting of 33 aluminum X-ray refractive lenses is considered. For solving the problem, a finite-difference method is suggested and investigated. It is shown that very small steps of the difference grid are necessary for reliable computation of propagation of X-ray waves through the system of lenses. It is shown that the wave phase is a function very quickly increasing...
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Nonlinearity shaping in nanostructured glass-diamond hybrid materials for optical fiber preforms
PublicationNanodiamond integration with optical fibers has proved a compelling methodology for magneto-optics. We reveal that the applicability of nanodiamonds in nonlinear optics goes beyond the previous demonstrations of frequency converters. Instead, we exploit the recently reported volumetric integration of nanodiamonds along the optical fiber core and show that the nonlinear response of glasses can be manipulated by nanodiamonds. By...
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Sol-gel Al2O3 antireflection coatings for silicon solar cells
PublicationPurpose: This paper presents the results of investigations on morphology and opticalproperties of the prepared aluminium oxide thin filmsDesign/methodology/approach: Thin films were prepared with use of sol-gel spincoating method. The changes of surface morphology were observed in topographic picturesperformed with the atomic force microscope AFM. Obtained roughness coefficients valueswere generated...