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UV-initiated green synthesis of metal nanoparticles by using plant extracts as photoreducing agents is of particular interest since it is an environmentally friendly, easy-to-maintain, and cost-effective method. Plant molecules that act as reducing agents are assembled in a highly controlled way which makes them suitable for metal nanoparticle synthesis. Depending on the plant species, their application for green synthesis of metal nanoparticles for diverse applications may contribute to the mediation/reduction in organic waste amounts, thus enabling the implementation of the circular economy concept. In this work, UV-initiated green synthesis of Ag nanoparticles in hydrogels and hydrogel’s thin films containing gelatin (matrix), red onion peel extract of different concentrations, water, and a small amount of 1 M AgNO3 have been investigated and characterized using UV-Vis spectroscopy, SEM and EDS analysis, XRD technique, performing swelling experiments and antimicrobial tests using bacteria (Staphylococcus aureus, Acinetobacter baumannii, Pseudomonas aeruginosa), yeasts (Candida parapsilosis, Candida albicans) and microscopic fungi (Aspergillus flavus, Aspergillus fumigatus). It was found that the antimicrobial effectiveness of the silver-enriched red onion peel extract–gelatin films was higher at lower AgNO3 concentrations as compared to those usually used in the commercially available antimicrobial products. The enhancement of the antimicrobial effectiveness was analyzed and discussed, assuming the synergy between photoreducing agent (red onion peel extract) and silver nitrate (AgNO3) in the initial gel solutions leading to the intensification of Ag nanoparticles production.

There is a growing need to develop lead-free shielding materials that are safe, low weight, durable, environmentally friendly, chemically and mechanically stable and customizable for specific applications. Fused deposition modeling (FDM), an additive manufacturing technique based on the extrusion of a thermoplastic filament into a 3D printed object one layer at a time, could be employed well in applications involving ionizing radiation due to its relatively low cost, design flexibility and high manufacturing precision. This study aimed at developing 3D printing composites that contain Titanium dioxide as a filler agent for shielding in a medical radiation environment. First, the effect of low-dose ionizing radiation (up to 15 Gy) on the mechanical properties of common 3D printing polymers, ABS, ULTRAT, PLA, NYLON, ASA and PETG, was investigated. Since ABS experienced the lowest variation in its ultimate tensile strength (±5%) and Young’s modulus (−5%/+11%), it was chosen as a matrix for a new extruded 3D filament containing TiO2 at 1 wt.%, 3 wt.%, and 5 wt.%. With the incorporation of TiO2 at different filler contents, the UTS of the ABS composites varied between 24.1 MPa and 28.4 MPa, with the highest value recorded for 3 wt.% TiO2. Young’s modulus values were dependent on both the TiO2 concentration and on the irradiation dose. In addition, the ABS/TiO2 composites with a higher filler content (3 wt.% and 5 wt.%) maintained their attenuation ability even after exposure to a radiation dose of 100 Gy as opposed to pure ABS, which exhibited a ~2.5% reduction in its mass attenuation coefficient after exposure to the same dose of radiation. The pilot investigation performed demonstrated that the newly developed ABS/TiO2 composite containing 5 wt.% of filler can be successfully employed to shield electronic devices operating in a radiotherapy room.

Polymer gels and films, due to their near equivalence to biological tissue, are amongst the most promising future dosimetry tools for medical applications. The application of polymer dose gels is limited by the sensitivity of dose readout methods and dose gel properties. It is a challenge to find suitable dosimeters for registration of doses delivered to the target by orthovoltage therapy units. The application of metal-particle-enriched polymer composites for dose registration in X-ray therapy might be an elegant solution, especially if recent dose-reading technologies exploring advantages of different physical phenomena are involved. In this work, X-rays from the orthovoltage therapy range were used for the irradiation of experimental samples. In addition, radiation-induced processes of formation of silver nanoparticles in AgNO3–PVA gels and in free standing AgNO3PVA films, also containing some additional solvents, namely glycerol, ethanol, and isopropanol, have been investigated, with the aim to apply the developed composites for medical dosimetry purposes. A simple and environmentally friendly method for the formation of free-standing AgPVA films at room temperature was proposed and realized for preparing AgPVA films for investigation. Radiation-induced synthesis of silver nanoparticles in AgPVA composites was investigated, analyzing LPSR-based UV-VIS spectral changes to the irradiated films with respect to irradiation doses, and dose-related tendencies were also evaluated. It was shown that AgPVA films were more sensitive for detection of doses from the interval 0–1.0 Gy, thus indicating potential application of AgPVA films for dosimetry purposes.

Recycling of electric and electronic waste products (e-waste) which amounted to more than 50 million metric tonnes per year worldwide is a massive and global operation. Unfortunately, an estimated 70 & ndash;80% of this waste has not been properly managed because the waste went from developed to low-income countries to be dumped into landfills or informally recycled. Such recycling has been carried out either directly on landfill sites or in small, often family-run recycling shops without much regulations or oversights. The process traditionally involved manual dismantling, cleaning with hazardous solvents, burning and melting on open fires, etc., which would generate a variety of toxic substances and exposure/hazards to applicators, family members, proximate residents and the environment. The situation clearly calls for global responsibility to reduce the impact on human health and the environment, especially in developing countries where poor residents have been shouldering the hazardous burden. on the other hand, formal e-waste recycling has been mainly conducted in small scales in industrialized countries. Whether the latter process would impose less risk to populations and environment has not been determined yet. Therefore, the main objectives of this review are: 1. to address current trends and emerging threats of not only informal but also formal e-waste management practices, and 2. to propose adequate measures and interventions. A major recommendation is to conduct independent surveillance of compliance with e-waste trading and processing according to the Basel Ban Amendment. The recycling industry needs to be carefully evaluated by joint effort from international agencies, producing industries and other stakeholders to develop better processes. Subsequent transition to more sustainable and equitable e-waste management solutions should result in more effective use of natural resources, and in prevention of adverse effects on health and the environment., Diagnosis, Monitoring and Prevention of Exposure-Related Noncommunicable Diseases (DiMoPEx) COST Action project [CA15129]; European UnionEuropean Commission, This work was supported by the Diagnosis, Monitoring and Prevention of Exposure-Related Noncommunicable Diseases (DiMoPEx) COST Action project (CA15129) and its Final Action Dissemination Grant from the European Union.

Matematikos ir gamtos fakulteto ištakomis Kaune laikomi 1920-ieji metai, kai buvo įsteigti Lietuvos Aukštieji Kursai, į kurių sudėtį įėjo ir Matematikos-fizikos skyrius. 1922 m. vasario 16 d., įkūrus Lietuvos universitetą Kaune, buvo įsteigtas Matematikosgamtos fakultetas, kuris vykdė veiklą iki 1940 m. rudens. 1940 m. rugsėjo 1 d. Matematikosgamtos fakulteto veikla Kaune sustabdyta, jis perkeltas į Vilnių. Visą, nuo Fakulteto įkūrimo iki sustabdymo, veiklos laiką Kaune Fakultetui vadovavo dekanas prof. Zigmas Žemaitis. 1993 m. rugsėjo 1 d. Kauno technologijos universitete Aukštosios matematikos (pakeičiant pavadinimą į Taikomosios matematikos), Bendrosios matematikos ir Fizikos katedrų pagrindu įsteigtas Fundamentaliųjų mokslų fakultetas, 2014 m. sausio 1 d. (at)gavęs istorinį Matematikos ir gamtos mokslų fakulteto pavadinimą ir skaičiuojantis jau 25-uosius savo veiklos metus. The origins of the Faculty of Mathematics and Natural Sciences in Kaunas are the early 1920, when the Lithuanian Higher Courses were established and included the Mathematical-Physical Department. On the 16th of February 1922, the University of Lithuania was created in Kaunas and the Faculty of Mathematics and Nature was founded as well. It acted up until autumn in 1940. All the time from the very beginning until the suspension, the Dean of the faculty was Professor Zigmas Žemaitis. Later on the 1st of September 1993, the Faculty of Fundamental Sciences was established on the basis of two departments – Kaunas University of Technology Department of Higher Mathematics (later re-named to Department of Applied Mathematics) and Department of General Mathematics and Physics. On the 1st of January, 2014 the faculty received its historical title – the Faculty of Mathematics and Natural Sciences and now is celebrating 25 years of activity.

Background Reconstruction and analysis of low doses received by the occupationally exposed medical radiation workers, especially nuclear medicine staff dealing with radioisotopes may significantly contribute to the understanding of radiation impact on individuals, assess and predict radiation related risks for the development of cancer or other specific diseases. Methods A pool of 2059 annual effective doses corresponding to 272 job's positions occupied by nuclear medicine and radiology workers for a certain time period over 26 years in five Lithuanian hospitals was investigated in order to analyze the occupational exposure tendencies to medical staff. Requested data, measured in terms of whole body dose, personal dose equivalent Hp(10), was obtained from the National Register of Sources of Ionizing Radiation and Occupational Exposure. Considering that nuclear medicine staff is dealing with open sources/radioisotopes, doses to extremities, Hp(0.07), were measured using thermoluminescent dosimeters (TLD) of LiF:Mg, Ti type. Lifetime risk estimations for the development of specific cancer (thyroid cancer and leukemia) for exposed radiation workers were performed using risk models included in BEIR VII report (BEIR VII, 2006). The conservative assessment of the thyroid exposure was performed using RadRAT 4.1.1 tool. Results Doses to radiology technologists and radiology nurses were found to be highest over the years. However, their annual doses never exceeded dose limit of 20 mSv and were following the same decreasing tendency as the doses of other personnel. There was no increase of doses to nuclear medicine staff observed after installation of two new PET/CT machines, indicating increased radiation protection culture and application of relevant technical and protective measures by the staff. Measured fingertip doses were 2–3 times higher than the hand doses measured with TLD ring and were dependent on the type and frequency of the nuclear medicine examination procedure and on the type and activity of isotopes used for examination. Conclusions For the first time, retrospective dose evaluation for the cohort of medical radiation workers was performed in the country. It enabled estimation of lifetime attributable risk for the development of two cancer types: thyroid and leukemia cancer among occupationally exposed medical radiation staff. Projected risk was low, ~10−5, however it was found that the risk of thyroid cancer for female staff was 5.7 times higher than for the males. Obtained results will be used for the predictive assessment of possible radiation induced health effects to occupationally exposed medical radiation workers.

Polymer gels are amongst the most promising future dosimetric tools for medical applications, since irradiated gels are capable to represent a phantom and a dosimeter with a 3D-dose distribution measurement capability and biological tissue equivalency in one. High spatial resolution of these gels but limited dose sensitivity, especially in low dose region, as well complicated and time consuming read out methods are the main issues needing improvement. Operating principle of plasmonic sensors which are commonly used in biotechnology to assess the concentration and reaction rate of various organic compounds, is based on the excitation of strong free electron oscillations (surface plasmon resonance, SPR) in the boundary layer between metal and dielectric using polarized light and measurement of the refracted light characteristics. Plasmonic sensors stand out from the other sensing technologies due to their high resolution and relatively low uncertainties. Combination of plasmonic sensors’ characteristics and capabilities of dosimetric gels is key when developing dosimetric gel based SPR sensors for point dose measurements and corresponding relatively simple, however sensitive, in-house made dosimetric system working in angular mode, all of which is presented in this paper. Developed plasmonic sensor itself comprised out of Au diffraction grating, extracted from commercial optical media disc, spin-coated with a thin dosimetric gel (nPAG or VIPET) layer. Fabrication procedure of the plasmonic sensor and creation of the corresponding optical read out system are discussed in this paper. Irradiation experiments performed with dosimetric gel based SPR sensor (point dosimeter) have shown the feasibility of this new type dosimetry system to measure low absorbed doses (up to 5Gy) and revealed the potential of this system to perform measurements with the dosimetric sensitivity up to two times higher as compared to other known optical dose evaluation methods. Key aspects regarding sensitivity and resolution of plasmonic dosimeters are also discussed.

3D printing technologies became an integral part of the medical environment due to their ability to produce relevant copies of human organs and tissues. This feature can be used by developing of radiotherapy/radiology phantoms for patient dose verification thus providing an excellent possibility for individualization of irradiation procedure.

Silver nanoparticles and polymethylmethacrylate (PMMA) nanocomposite was preparedin situby photo-induced thermal reduction method. The interfacial interaction of Ag nanoparticles and PMMA polymer is investigated using Fourier transform infrared spectroscopy (FTIR). Optical properties of Ag/PMMA films were characterized by UV-Vis and FTIR absorption spectroscopy. Effects of the UV and heat-treatment time on the formation of silver nanoparticles in PMMA matric matrix were studied in detail. These investigations proposed new nanocomposite structures. They can be defined as plasmonic materials with improved optical properties. Ag/PMMA structures may found a number of technological applications: in optical devices, various plasmonic sensors or even in nanomedicine.

Ag–PVP (silver-polyvinylpyrrolidone) films were spin-coated on silica substrates from Ag–PVP colloidal solution. Formation of nanoparticles in deposited films was achieved by photoreduction of silver ions due to UV irradiation of prepared samples. Presence of spherical nanoparticles in UV irradiated samples was identified according to the measured absorbance peaks of samples that were observed in the range 410–430 nm and were explained by surface plasmon resonance phenomenon. Produced nanocomposite films were further on modified additionally irradiating them with gamma photons within the dose range (2–50) Gy. Plasmonic and mechanical properties of gamma irradiated nanocomposite films have been investigated by UV–vis spectroscopy and AFM and compared to those obtained after prolonged UV irradiation of films.

) antennas fastened to an end of a transmission line were pulse-excited by 0.5 ns rise time pulsesfor radiation of ultra-wideband signals. Wideband horn antennas were used for receiving the signals and wideband samplingoscilloscope was used for their visualization. The signals were registered in 1Œ5.6 GHz frequency range and had the quasi-Gauss envelope form. The plane antennas made of Cu, resistive Al, and resistive nanostructured Ni thin lms on supportingpolyethylene terephthalate of 100 „m thickness were used. It is shown that the radiation induced by pulsed excitation canbe used to control parameters of resistive coatings, including nanostructured ones, during a deposition process. The metallicnanostructured thin lms could be used to create plane radiating and receiving antennas having resistive elements and adaptedfor ultra-wideband signals. Ultra-wideband antennas with resistive nanostructured coatings, which have properties that canbe changed by external electric or magnetic elds or by optical radiation, can be used for modulation of radiated pulses.Further experimental studies are proposed to elaborate metallic nanostructured thin lms suitable to withstand possible damagesinduced by short high power electrical pulses.

In the present research silver nanoparticles were produced by e-beam evaporation of metal on polymer-modified silica substrate at room temperature (20 °C) and elevated temperature (80 °C). Modification of the silica substrate was done by different weight concentration polymer (PMMA/PS) blends formed from the polymer solutions by spin coating. The silver layer thickness varied from 1 nm to 10 nm. Silver nanoparticles in polymer matrix were characterized by XRD, AFM and UV–vis spectrometry. The crystalline silver nanoparticles showed surface plasmon resonance (SPR) with absorption maximum at 420–550 nm that was dependent on the silver layer thickness, PMMA and PS weight concentration in polymer blends and substrate temperature during vacuum deposition. The silver nanoparticles in polymer with selective light properties resulting from the controlled SPR shifting to the UV–vis wavelength region were produced.

SiO x doped diamond-like carbon (DLC) films were synthesized by direct ion beam from hexamethyldisiloxane vapor. Effects of ion beam energy were studied. Variation of atomic concentration of the oxygen versus carbon with ion energy has been observed. Raman scattering spectroscopy didn’t indicate essential changes in structure of the films deposited at different ion beam energies. The synthesized films were atomically smooth. Depending on the ion energy the refractive index of the SiO x doped diamond-like carbon films varied within 2.1–2.5 and increased with increase of energy. The contact angle with water for all samples was only 61–64°.

Photoelectron spectroscopy has been used to study the Gd/EuTe multilayers structure covered with a thin (100 A) Al film. The study of the main core level and valence band photoemission spectra has shown no interaction between Gd and EuTe layers. Gadolinium was in pure metallic state and the ions of Eu were found divalent in the Gd/EuTe multilayers structure. The europium ions spectra analysis indicates that Ar+ ion sputtering of the sample surface leads to a deviation from stoichiometry in the near surface region of the EuTe layers and to the appearance of Eu3+ species in uppermost layers of the Gd/EuTe multilayers structure. The long-time exposure to the XPS ambient gases has been characterized from the analysis of europium 3d core level spectra.

The influence of plasma processing of silica and crystalline silicon substrates on the formation of polymeric layers of PS/PMMA blends by sorption from 50 vol. % concentration toluene solutions was analyzed. The morphology dependence of PS/ PMMA blend films on the type and condition of substrate processing was studied by X-ray photoelectron spectroscopy (XPS), ellipsometry and atomic force microscopy (AFM). It was shown that reduction of carbon and oxygen components from the surface contaminants as well as the existence of a nonstoichiometric SiOx layer on the Si surface contributed to the hydrophilicity of the substrate. These processes can be used to produce thin nanostructured polymer blend films.

The successive ionic layer adsorption and reaction (SILAR) technique involves growth of thin films from solution, ionic layer by ionic layer at room temperature and normal pressure. The aim of this work is to characterize SILAR grown PbS thin films (15–100 nm) on silicon substrates using different lead-precursor solutions. The X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy and atomic force microscopy investigations have been performed to compare the properties of the films grown with different lead precursor solutions. The PbS ultra thin films were polycrystalline and cubic. The films were stoichiometric and contained some oxygen. The film roughness and crystallite size could be controlled by choosing the lead precursors.

Lead sulfide thin films were grown on (100)Si and (111)Si crystalline substrates by successive ionic layer adsorption and reaction, (SILAR), technique from solution phase at room temperature and normal pressure. The stress development, crystallinity and crystallite size, morphology and roughness and composition of the films were characterized as a function of the film thickness. The PbS thin films were polycrystalline and cubic. The residual stress in PbS was tensile and changed depending on the growth mode and thickness of the PbS films.

In this study lingonberry and cranberry juices were used for silver nanoparticle synthesis. The berry juices were characterized by total phenolics, total anthocyanins and benzoic acid content, respectively 1.9-2.7mg/ml, 55.2-83.4mg/l and 590.8-889.2mg/l. The synthesis of silver nanoparticles was performed at room temperature assisting in solutions irradiated by ultraviolet for 30min. Ultraviolet-visible (UV-vis) spectroscopy and microscopy confirmed the formation of nanoparticles as well as the dark red color of colloid of silver samples showed the formation of stable nanoparticles. Broad localized surface plasmon resonance (LSPR) peaks in UV-vis spectra indicated the formation of polydispersive silver nanoparticles and LSPR was observed at 485nm and 520nm for the silver nanoparticles synthesis using lingonberry and cranberry juices, respectively. The antimicrobial activity of silver nanoparticles was determined against the reference strains of microorganisms that could be found in food products: Staphylococcus aureus ATCC 25923, Salmonella typhimurium ATCC 13076, Listeria monocytogenes ATCC 19111, Bacillus cereus ATCC 11778, Escherichia coli ATCC 25922, Bacillus subtilis ATCC 6633, Candida albicans ATCC 10231 and foodborne B. cereus producing and non-producing enterotoxins. Silver nanoparticles showed a broad spectrum of antimicrobial activity and were most active against S. aureus ATCC 25923, B. subtilis ATCC 6633 and B. cereus ATCC 11778 reference cultures, and less active against C. albicans ATCC 10231 and foodborne B. cereus. It can be concluded that lingonberry and cranberry juices could be used as bioreductants for silver ions.

In the present study SiO x containing diamond-like carbon (DLC) films were synthesized by the closed drift ion source from hexamethyldisiloxane vapor. Kinetics of the growth of DLC films was investigated using optical emission spectroscopy (OES). Structure, chemical composition, electrical and optical properties of the synthesized films were studied. The effects of ion beam energy were investigated. The main atomic hydrogen Balmer series lines and the intense broad CH group related peak were detected in the OES spectra registered in-situ during SiO x containing diamond-like carbon film synthesis. The intensity ratio of H-β/CH peaks increased with the increase of applied ion beam energy. It was explained by activation of the dissociation of the hexamethyldisiloxane molecules. Changes of the structure of the diamond-like carbon films were observed for the films deposited under intense dissociation conditions.

In this study SiOx containing amorphous hydrogenated carbon (a-C:H/SiOx) and nitrogen-doped a-C:H/SiOx (a-C:H:N/SiOx) films were deposited on polyvinylpyrrolidone (PVP) templates of variable thickness using a Hall-type closed drift ion beam source with constant irradiation parameters. A detailed surface characterization was followed using atomic force microscopy (AFM) topography images, surface morphology parameters, height distribution histograms and bearing ratio curves with hybrid parameters. The AFM analysis directly showed that the a-C:H/SiOx/PVP and a-C:H:N/SiOx/PVP composite films represent different morphologies with characteristic surface textures. Surface adhesive properties were evaluated by measuring the force required to separate the AFM tip from the surface by means of AFM force-distance curves. The variance in adhesion force detected was lower for a-C:H/SiOx/PVP composite films due to lower structural homogeneity of the surfaces. Fourier transform infrared spectroscopy analysis was performed to study the blend behavior of PVP upon a-C:H/SiOx and a-C:H:N/SiOx direct ion beam deposition. It was determined that interfacial interactions of PVP with the direct ion beam induced changes in the carbonyl group of the PVP and are dependent on the carrier gas used for the synthesis of the amorphous hydrogenated carbon films.

In the recent years fundamental research involving the nanodimensional materials has received enormous momentum for observing and understanding new types of plasmonic materials and their physical phenomena occurring in the nanoscale. Mechanical and optical properties of these polymer based nanocomposite structures depend not only on type, dimensions and concentration of filler material, but also on a kind of polymer matrix used. By proper selection of polymer matrix and nanofillers, it is possible to engineer nanocomposite materials with certain favorable properties. One of the most striking features of nanocomposite materials is that they can expose unique optical properties that are not intrinsic to natural materials. In these researches, nanocomposite structures were formed using polymer (PMMA) as a matrix, and silver nanoparticles as fillers. By hot embossing procedure a diffraction grating was imprinted on formed layers. The effect of UV exposure time on nanocomposite structures morphology, optical (diffraction effectiveness, absorbance) and mechanical properties was investigated. Results were confirmed by UV-VIS spectrometer, Laser Diffractometer, PMT- 3 and AFM. Investigations proposed new nanocomposite structures as plasmonic materials with improved optical and mechanical properties, which may be applied for a number of technological applications: micro-electro-mechanical devices, optical devices, various plasmonic sensors, or even in DNA nanotechnology.

The rapid development of micro- and nanostructures containing silver nanoparticles is based on their unique physical properties. Despite the new applications of silver nanoparticles in nanomedicine are under heavy discussions, silver nanoparticles could be used in liquid radiation detectors thanks to the irradiation-induced surface plasmon resonance (SPR) phenomena observed in the colloidal solutions. Silver nitrate (1 mM AgNO(3)) and sodium citrate (1 wt% and 5 wt% C(6)H(5)O(7)Na(3)) were used as precursors for the fabrication of colloidal solutions. Prepared solutions were exposed to gamma-rays from a (60)Co gamma therapy unit 'Rokus-M' to varying absorbed doses, from 2 to 250 Gy. A UV/VIS/NIR spectrometer (Avantes-2048) was used for the measurement of the optical properties (absorbance) of the silver solutions. It was found that an initial absorbed dose of 2 Gy induced the formation of spherical silver nanoparticles as it was indicated in the absorbance spectrum of the solution, which had a well-pronounced absorption maximum at the wavelength of 410 nm. There is a potential to measure absorbed doses down to around 20 mGy. The SPR peaks at the wavelengths of 500-700 nm were found at the highest investigated doses >100 Gy, indicating the presence of silver nanorods. The colour of colloidal solutions ranged from pale yellow to green and was dependent on the absorbed dose. The investigation has shown that density, size and shape of synthesised silver nanoparticles are dependent on the absorbed dose and that shape transformations of the particles due to irradiation are possible. Application of colloidal solutions containing silver nanoparticles for dosimetric purposes is discussed on the basis of the obtained results.

Forming structures similar to or smaller than the optical wavelength offers a wide range of possibilities to modify the optical properties of materials. Tunable optical nanostructures can be applied as materials for surface-enhanced spectroscopy, optical filters, plasmonic devices, and sensors. In this work we present experimental results on technology and properties of periodical, polymer based optical structures modified by ordered adsorption of silver nanoparticles. These structures were formed combining UV hardening and dip coating from colloidal solutions. We have investigated the influence of silver nanoparticles assembly on the ambient conditions (deposition temperature and time) and surface features (periodicities and shape) of the template micro structures. Optical absorbance as well as morphology of the structures containing silver nanoparticles were investigated by UV-VIS spectroscopy, AFM, SEM and optical microscopy. The influence of silver nanoparticles on the optical properties of the structures was investigated by polarized light spectroscopy (Grating Light Reflection Spectroscopy - GLRS). From the results of this study we propose a low cost procedure for fabricating structures that could be potentially new type of plasmonic sensors exploiting surface enhanced plasmon resonance in silver nano structures.

Silver nanoparticles have received considerable attention due to their attractive physical and chemical properties. The surface plasmon resonance and large effective scattering cross section of individual silver nanoparticles make them ideal candidates for molecular labeling, where phenomena such as surface enhance Raman scattering (SERS) can be exploited. In addition, silver nanoparticles have recently been shown to be a promising antimicrobial material. In the present research silver colloid was produced by sodium citrate reduction. The colloidal silver was incorporated by dip-coating to the polymer substrate. X-Ray Fluorescence Spectroscopy (XRF), Atomic force microscopy (AFM), ultraviolet-visible spectroscopy (UV-VIS ) and SERS indicate that the produced structures include metallic crystalline silver nanoparticles. The surface plasmon resonance peak in absorption spectra of silver particles showed an absorption maximum at 420-500 nm. The silver - polymer nanocomposites structures with selective light properties as a result of plasmon resonance shifting in the UV-VIS wavelength region were produced.

We present a new group of piezoelectric nanocomposite thin films based on integrating piezoelectric material poly(vinylidene fluoride) and nanoparticles of barium titanate in a matrix of an organic polymer poly(methyl methacrylate). Implementation of piezoelectric properties in designed new nanocomposites allows us not only to increase the sensi- tivity and functionality of the overall system, where this material is used, but also to expand the application fields in sensing and actuating systems. Results implied that new nanostructures fabricated by nanoimprint lithog- raphy exhibit good piezoelectric, surface, and mechanical properties and allow independent control of tribological properties. Formed nanocompo- site systems were integrated in designing optical components employed in medicine for sensing applications. © The Authors. Published by SPIE under a Creative Commons Attribution 3.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI. (DOI: 10.1117/1.JMM.12.4.043004)

The successive ionic layer adsorption and reaction (SILAR) technique was used to grow double layer structures of CdS-PbS. The growth of thin films by the SILAR technique from diluted aqueous solutions was achieved, ionic layer by ionic layer, at room temperature and normal pressure. The thin films on silicon were characterized by XRD, AFM, XPS. It was established that a double layer could be grown on crystalline silicon and that the morphology and crystallinity of the films could be controlled by changing the lead precursor.