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Pure niobium substrates were coated using laser cladding method. Pure molybdenum, Yttria Stabilized Zirkonia (YSZ) and corundum (Al2O3) powders were used as coating materials. Coatings were deposited on specimens as seperate paths with 3÷10mm width and 40mm of length. Two different laser power 3kW and 4kW were tested during deposition. In order to assess the quality of the Mo-YSZ and Mo-Al2O3 coatings, the light microscopy, Scanning Electron Microscopy (SEM), chemical analysis (EDS) and Vickers hardness test investigation were performed. The surface roughness and wear volume were also measured. As a result of YSZ-Mo powder cladding on the Nb substrate the composite layers were obtained without cracks and porosity not exceeding 1 μm. In addition, an increase in hardness of about 450 HV0.5 was revealed. As a result of Al2O3-Mo powder cladding on the Nb substrate the composite layers with many voids and cracks were obtained for each of the cladding variants.

Magnetic nanoparticles of Fe3O4 doped by different amounts of Y3+ (0, 0.1, 1, and 10%) ions were designed to obtain maximum heating efficiency in magnetic hyperthermia for cancer treatment. Single-phase formation was evident by X-ray diffraction measurements. An improved magnetization value was obtained for the Fe3O4 sample with 1% Y3+ doping. The specific absorption rate (SAR) and intrinsic loss of power (ILP) values for prepared colloids were obtained in water. The best results were estimated for Fe3O4 with 0.1% Y3+ ions (SAR = 194 W/g and ILP = 1.85 nHm2/kg for a magnetic field of 16 kA/m with the frequency of 413 kHz). The excellent biocompatibility with low cell cytotoxicity of Fe3O4:Y nanoparticles was observed. Immediately after magnetic hyperthermia treatment with Fe3O4:0.1%Y, a decrease in 4T1 cells’ viability was observed (77% for 35 μg/mL and 68% for 100 μg/mL). These results suggest that nanoparticles of Fe3O4 doped by Y3+ ions are suitable for biomedical applications, especially for hyperthermia treatment.

One of the potential implementation of mesoporous silica nanomaterials (MSNs) is their use in biomedical applications as adsorbents or carriers of various bioactive substances. In this study, we attempted to fabricate silica nanomaterials containing copper and silver that were introduced into the MSN matrix, for the first time using oxalate compounds as a metal source. The syntheses were carried out using hydrothermal and impregnation methods. Structure studies revealed that the obtained nanoparticles were of a spheroidal shape and most had diameters in the range 200–500 nm. Silver and copper were found to be grouped into clusters in most samples, except in copper-decorated MSNs prepared with the impregnation method, which had an even distribution of metal atoms throughout the volume of the granule. An evaluation of the cytotoxic and irritating effects revealed that the preferred candidates for potential future applications in medicine or cosmetology among materials obtained with the presented method are the copper-conjugated MSNs.

Computed tomography (CT) of aluminum welded joint specimen has been performed. On the tomographic cross sections some defects have been found. To verify them the metallography cross sections of welded has been done. It was found that selected defects are micro cracks.

Perovskites, garnets, monoclinic forms, and lately also oxyhydroxides doped with rare-earth ions have been drawn large attention due to their beneficial optical and photovoltaic properties. In this work, we have shown that several forms of crystals from Y–Al–O family can be synthesized using microwave driven hydrothermal technique using different pH and post-growth annealing at different temperatures. The structural and optical properties of these crystals were investigated as a function of hydrothermal crystallization conditions. For this purpose, x-ray diffraction, scanning electron microscopy, energy-dispersive x-ray spectroscopy, transmission electron microscopy, photoluminescence, and photoluminescence excitation studies were performed. All the structures have been doped with Eu3+ ions which are known as a local symmetry sensor because various symmetries generate different crystal fields and thus affect their luminescence spectra. The optical properties of the obtained nanoparticles in correlation with their structure and chemical composition are discussed.

This paper presents the development of indigenous hybrid rocket technology, using 98% hydrogen peroxide as an oxidizer. Consecutive steps are presented, which started with interest in hydrogen peroxide and the development of technology to obtain High Test Peroxide, finally allowing concentrations of up to 99.99% to be obtained in-house. Hydrogen peroxide of 98% concentration (mass-wise) was selected as the workhorse for further space propulsion and space transportation developments. Over the course nearly 10 years of the technology’s evolution, the Lukasiewicz Research Network—Institute of Aviation completed hundreds of subscale hybrid rocket motor and component tests. In 2017, the Institute presented the first vehicle in the world to have demonstrated in-flight utilization for 98% hydrogen peroxide. This was achieved by the ILR-33 AMBER suborbital rocket, which utilizes a hybrid rocket propulsion as the main stage. Since then, three successful consecutive flights of the vehicle have been performed, and flights to the Von Karman Line are planned. The hybrid rocket technology developments are described. Advances in hybrid fuel technology are shown, including the testing of fuel grains. Theoretical studies and sizing of hybrid propulsion systems for spacecraft, sounding rockets and small launch vehicles have been performed, and planned further developments are discussed.

Sono- and photochemical reactions were combined in the synthesis of Pd-Fe- and Pt-Fe-doped titania-based photocatalysts supported on zeolite Y. In the applied procedure, no harmful reducing agents were used. The resulting photocatalysts were characterized using diffuse reflectance UV–vis spectroscopy, high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), N 2 physisorption and inductively coupled plasma mass spectrometry (ICP-MS) techniques. The applied methodology leads to the formation of a mainly metallic form of platinum and oxidized forms of palladium and iron, with respect to different reduction potentials of metals. The photocatalytic degradation of phenol under UV light was applied as a test reaction. The photocatalyst containing Pt-Fe showed better results in this reaction in comparison with the Pd-Fe material, mainly because of the presence of the metallic form of platinum.

The effect of the ZnO nanoparticles (NPs) size on the photocatalytic degradation of phenol in a water solution under the influence of UV and Vis radiation was discussed. For the first time, research on photocatalytic degradation has used ZnO NPs produced by only one method (microwave solvothermal synthesis without heat treatment or other processes of reduction/oxidisation of the surface of NPs samples). ZnO NPs average size was determined using the Scherrer's formula, Nanopowder XRD Processor Demo web application, by converting the results of the specific surface area-density, and TEM tests. The ZnO NPs (average size between 23 nm and 71 nm) characterise by uniform morphology and narrow size distribution. The photocatalytic performance of ZnO NPs increases with the increase of the particle size and the decrease of the specific surface area. For both UV and Vis radiation, the highest reaction rate for phenol degradation was found for ZnO sample with the average particle size of 71 nm. Low concentrations of resorcine and hydroquinone (co-products of phenol degradation) were found for UV light photocatalytic test. However, high concentrations of hydro- and p-benzoquinone were observed for visible light photoactivity due to the slower decomposition of the main contamination associated with the utilized of other type of radiation. The photocatalytic activity was found to be attributable to the decrease in the charge carrier recombination rate.

The structural, electronic, and magnetic properties of low-energy rhenium implanted c-Si are examined for the first time. The damage created by rhenium ions and the following partial reconstruction of the silicon host matrix after rapid thermal annealing (RTA) are investigated as a function of the fluence. Rutherford backscattering spectrometry (RBS) results reveal that the implanted ions are located in the near-surface region with the distribution maximum at about 23 nm below the surface. The analysis of rhenium-depth distribution using the McChasy code shows that the implanted Re-ions are located in the interstitial lattice positions. The RTA leads to a partial recovery of the silicon crystal structure. According to the RBS results, the formed inclusions are not coherent with the silicon host matrix causing an increase of the lattice distortion. Analysis of channeled RBS/c spectra carried out by the McChasy code revealed different levels of bent channels in damaged regions suggesting bimodal distribution of inclusions in the silicon. Studies of high-resolution X-ray photoelectron spectroscopy (XPS) conducted after the RTA showed the shift of Re 4f7/2 binding energy (BE) by +0.68 and + 0.85 eV with respect to metallic rhenium for the samples with lower/higher fluencies, respectively. Complex XPS, density functional theory (DFT) simulations, and transmission electron microscopy (TEM) data analysis allowed us to conclude that the near-surface layer of the sample (∼10 nm) consists of nanoinclusions with cubic and/or hexagonal ReSi. In the middle area of the samples, much larger nanoinclusions (>10/20 nm for higher/lower fluencies, respectively) containing pure metallic rhenium inside are formed. The RTA increases the magnetic moment of the sample with the lower dose nearly 20-fold, whereas in the sample with the higher dose a 3-fold increment is observed only. The magnetic response of the examined systems after the RTA indicates a presence of magnetic interactions between the nanoinclusions resulting in the system exhibiting super-spin glass or super-ferromagnetism.

In photodynamic therapy (PDT), photosensitizer (PS) molecules are irradiated by light to generate reactive oxygen species (ROS), the presence of which subsequently leads to cell death. At present, the modality is limited to the treatment of skin diseases because of the low tissue penetration of visible or ultraviolet light required for producing ROS. To increase tissue penetration and extend the therapeutic possibilities of PDT to the treatment of deep-seated cancer, rare-earth doped nanoparticles capable of up-converting infrared to visible light are investigated. These up-converting nanoparticles (UCNPs) are conjugated with PS molecules to efficiently generate ROS. In this work, we employ hexagonal β-NaYF4:Yb3 + ,Er3 + as UCNPs and Rose Bengal (RB) as PS molecules and demonstrate efficient in vitro PDT using this nanoformulation. Covalent bonding of the RB molecules is accomplished without their functionalization-an approach which is expected to increase the efficiency of ROS generation by 30%. Spectroscopic studies reveal that our approach results in UCNP surface fully covered with RB molecules. The energy transfer from UCNPs to RB is predominantly non-radiative as evidenced by luminescence lifetime measurements. As a result, ROS are generated as efficiently as under visible light illumination. The in vitro PDT is tested on murine breast 4T1 cancer cells incubated with 250 µg ml-1 of the nanoparticles and irradiated with NIR light under power density of 2 W cm-2 for 10 minutes. After 24 hours, the cell viability decreased to 33% demonstrating a very good treatment efficiency. These results are expected to simplify the protocols for preparation of the PDT agents and lead to improved therapeutic effects.

Commercial TiO2 (P25), alone or in the presence of graphite oxide (GO), was exposed to ultrasound treatment (US) with the objective to modify the surface of nanoparticles through introducing defects and chemical heterogeneity, and to build the composite with GO of synergistic features. The obtained materials were extensively characterized using XRD, HR-TEM, TA-MS, FTIR, XPS, potentiometric titration, adsorption of nitrogen, and UV/Vis diffuse reflectance techniques. The results showed that the US treatment/activation led to the formation of defects on the surface of the TiO2 nanoparticles, which were associated with an increase in the amount of terminal hydroxy groups, and which resulted in narrowing of the band gap energy. The composite formed upon the ultrasonic activation contained partially reduced GO particles deposited on the surface of TiO2 aggregates and bonded with the titania phase through its carboxylic groups existing at the edges of small defectous graphene particles, leading to a high volume of mesopores formed between the particles/aggregates of the nanoparticles. The US-treated materials showed a superior bifunctional detoxification performance, to adsorb and photocatalytically decompose vapors of a chemical warfare agent surrogate, as a result of the surface alteration/activation and an increase in the porosity.

Despite the significant technological progress achieved in the past decades in the medical field, device-related infections carry a heavy social and economic burden. Surface modification of medical equipment is one of the most interesting approaches employed to improve the antibacterial activity of a material. Herein, we developed a process for the gold nanoparticle modification of a poly(vinyl chloride) laryngeal tube, which typically serves as an airway management device. In our study, we focused specifically on increasing the antimicrobial properties of the material while maintaining its biocompatibility. We applied two different modification methods to the poly(vinyl chloride) laryngeal tube. An increase in the antimicrobial activity of the surface was observed for both methods. In addition, the adsorption of bacterial cells on the material surface was assessed. We determined that the number of colonies cultured in the presence of the gold nanoparticle-modified samples or absorbed to the material surface decreased significantly compared with the control group. The trend was observed for both Gram-positive and Gram-negative strains. Moreover, it was established that the designed material did not exhibit a lethal impact on a control cell line. Finally, we noted discrepancies in the growth of bacteria cultured in the presence of modified or unmodified PVC material as well as differences in cell adherence to its surface. The proposed poly(vinyl chloride) modifications are most effective against Gram-positive bacteria, especially L. monocytogenes. Nevertheless, it ought to be emphasized that due to their different properties, each strain requires an individual approach.

Upconverting Gd2O3 nanoparticles (NPs) doped 1% Er3+ and 18% Yb3+ permits one to perform optical imaging. Because of the presence of Gd3+ they are useful in MRI. The main challenge is to enhance the NPs upconversion efficiency. As a result of co-doping the NPs with Zn2+ ions, achieved using microwave-induced solution combustion synthesis, we obtained optimal upconversion quantum yields (UQYs). The breakdown of the local crystal field symmetry around the rare earth ions, maximal in the presence of 5% of zinc, may be responsible for the highest observed UQY. The upconversion of IR light results in emission of visible red light mainly at 660 nm and at 550 nm. Optimized red photoluminescence of the samples observed in an organic environment was examined as a function of the laser power density to explain the mechanism of the upconversion emission. Paramagnetic properties of the NPs were determined by superconducting quantum interference device measurements. The non-functionalized nanoparticles incubated with HeLa cells were endocytosed and imaged by confocal laser scanning microscopy. We investigated their localization inside HeLa cells for various incubation times and NPs concentrations. PrestoBlue toxicity assay was performed to test the NPs bio-efficacy.

In this paper we present the results of the investigations of nanostructured C-Pd films for hydrogen sensing applications. These C-Pd films were prepared by physical vapor deposition and then annealed in an argon flow at the temperature of 500°C. The structure and morphology of the prepared C-Pd films were investigated using transmission electron microscopy and energy dispersive X-ray spectroscopy. We studied the infiuence of hydrogen on the electrical properties and crystal structure of C-Pd films. It was shown that film resistance changes depended on hydrogen concentration. At lower hydrogen concentration (up to 2 vol.%), the films response increased proportionally to [H2], while above 2 vol.% H2, it was almost constant. This is connected with the formation of a solid solution of hydrogen in palladium at lower H2 concentration and the creation of palladium hydride at higher H2 concentration. X-ray diffraction was used to confirm the formation of Pd-H solid solution and palladium hydride.

Silicon single crystals were implanted with 160 keV Mn+ ions to a dose of 1×1016 cm−2 and next annealed for 1 h up to 1070 K under ambient pressure. Glancing incidence diffraction research performed using synchrotron radiation indicated that the post-implantation treatment influenced the creation of Mn4Si7 nanoinclusions. The dimensions and concentration of these inclusions, calculated from distribution of the X-ray diffuse scattering intensity are dependent on annealing temperature. The sizes and shapes of the inclusions were also determined by high-resolution transmission electron microscopy. Magnetic properties of the Si:Mn samples were studied using superconducting quantum interference device. The origin of ferromagnetic ordering is discussed in terms of the size of nanoinclusions.

In this paper we present selective hydrogen sensor for application working in methane presence. Our sensor is based on C-Pd films prepared by physical vapor deposition (PVD) method. The morphology and topography of these films were characterized using SEM and TEM techniques. The sensor evaluation was performed in gas containing different hydrogen concentrations in N 2 /CH 4 mixture. For comparison the changes of films response for H 2 /N 2 mixture were also measured. It was found that C-Pd films selectively detected hydrogen in the presence of methane in the surrounding atmosphere. Furthermore, CH 4 presence does not affect the kinetics of interaction of hydrogen with the C-Pd films.

Transmission Electron Microscopy (TEM) analysis of carbonaceous films that contain palladium nanoparticles were carried out. These layers will be used in next-generation hydrogen sensors. The investigated films were obtained in Physical Vapor Deposition (PVD) and followed in Chemical Vapor Deposition (CVD) processes. For TEM analysis, cross-sections specimen (lamella) of both samples (i.e. PVD and PVD/CVD) were prepared with the usage of Focus Ion Beam (FIB). TEM analysis of the cross-sections determined the films' thickness, which were ∼200 nm and ∼300 nm for PVD and PVD/CVD films respectively. The greater thickness of the PVD/CVD films was associated with xylene decomposition and consecutive formation of porous structure. Our studies allowed to obtain some information about the distribution of palladium crystallites and porous carbon in the both layers of Pd–C. Furthermore, aggregation of small (∼2 nm) Pd nanocrystallites around the larger ones was observed for PVD and PVD/CVD films. In the PVD/CVD films a polycrystalline palladium have been observed.

Zinc oxide nanoparticles (ZnO NPs) were obtained by the microwave solvothermal synthesis (MSS) method. The precursor of the MSS reaction was a solution of hydrated zinc acetate in ethylene glycol with water addition. It was proved that by controlling the water concentration in the precursor it was possible to control the size of ZnO NPs in a programmed manner. The less the water content in the precursor, the smaller the size of ZnO NPs obtained. The obtained NPs with the average particle size ranging from 25 nm to 50 nm were characterised by homogeneous morphology and a narrow distribution of particle sizes. The following parameters of the obtained ZnO NPs were determined: pycnometric density, specific surface area, phase purity, chemical composition, lattice parameters, average particle size, and particle size distribution. The average size of ZnO NPs was determined using Scherrer’s formula, Nanopowder XRD Processor Demo web application, by converting the results of the specific surface area, and TEM tests using the dark field technique. ZnO morphology and structure were determined using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The test performed by the X-ray powder diffraction (XRD) confirmed that crystalline ZnO, pure in terms of phase, had been obtained.

In this paper we presented results of investigation of carbonaceous-palladium materials obtained in the CVD (Chemical Vapor Deposition) process. This investigations were carried out with transmission electron microscopy (TEM) and scanning electron microscopy (SEM), equipped with spectrum imaging for cathodoluminescence (CL). The composites will be applied as a active layers in hydrogen and also hydrocarbons detectors. Our measurements showed that some of Pd nanoparticles have a graphite shell and also are optically active. This particle in CL spectrum reveal the peak wavelength around 525 nm (2,36 eV).

Magnetic nanoparticles prepared with iron oxides and N -benzyl- O -carboxymethylchitosan, an amphiphilic chitosan derivative, were prepared through the incorporation method and characterized by Fourier infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), transmission electron microscopy (TEM), Mossbauer spectroscopy, and magnetization measurements. The γ-Fe 2 O 3 nanoparticles proved to be spherical and well crystallized, and some aggregation behavior was observed. The particles containing the polymer presented saturation magnetization of 18.4 emu g −1 and roughly superparamagnetic behavior. The material was used to adsorb three cationic dyes from aqueous solution (methylene blue, crystal violet, and malachite green). The adsorption process preferably followed the Langmuir–Freundlich isotherm and pseudo-second-order kinetic model. The removal of the dyes was optimized using a 3 2 factorial design, and the initial dye concentration proved to be more influential in dye adsorption than the temperature of the system.

We have studied the synthesis of ZnO nanostructures over a wide range of parameters to determine the kinetics of the nanocrystals growth. The initial rapid nucleation and growth is kinetically controlled, the subsequent ZnO nanocrystals growth is thermodynamically controlled through the diffusion limited Ostwald coarsening. The ZnO coarsening rates increased with number of alcohol’s alkyl group carbons and temperature increase, pointing to importance of the solvent viscosity, dielectric constants, surface energy and the bulk solubility. The results are consistent with the Lifshitz–Slyozov–Wagner model. For all alcohols, in the NaOH induced reaction, a lower activation energy was observed compared to the aqueous reaction. A lower ZnO solubility, obtained by the water synthesis could be responsible for these observations. Our results point to the importance of the reactant selection in controlling the kinetics of the nanostructure formation, their size and the nature of the surface defects responsible for their luminescence.

This article presents the method of size control of cobalt-doped zinc oxide nanoparticles (Zn1−xCoxO NPs) obtained by means of the microwave solvothermal synthesis. Zinc acetate dihydrate and cobalt(II) acetate tetrahydrate dissolved in ethylene glycol were used as the precursor. It has been proved by the example of Zn0.9Co0.1O NPs (x = 10 mol %) that by controlling the water quantity in the precursor it is possible to precisely control the size of the obtained Zn1−xCoxO NPs. The following properties of the obtained Zn0.9Co0.1O NPs were tested: skeleton density (helium pycnometry), specific surface area (BET), dopant content (ICP-OES), morphology (SEM), phase purity (XRD), lattice parameter (Rietveld method), average crystallite size (FW1/5/4/5M method and Scherrer’s formula), crystallite size distribution (FW1/5/4/5M method), and average particle size (from TEM and SSA). An increase in the water content in the precursor between 1.5% and 5% resulted in the increase in Zn0.9Co0.1O NPs size between 28 nm and 53 nm. The X-ray diffraction revealed the presence of only one hexagonal phase of ZnO in all samples. Scanning electron microscope images indicated an impact of the increase in water content in the precursor on the change of size and shape of the obtained Zn0.9Co0.1O NPs. The developed method of NPs size control in the microwave solvothermal synthesis was used for the first time for controlling the size of Zn1−xCoxO NPs.

The structural investigation of InGaN/GaN:Si multiple quantum well (MQW) samples grown by low-pressure metal-organic vapor phase epitaxy (LP-MOVPE) in a two temperatures (2T) process on high-pressure GaN mono-crystalline substrates is performed by transmission electron microscopy (TEM). A sample in which barriers and wells were grown at 780 °C is compared with another in which the barriers were deposited at 900 °C and the wells at 730 °C. For both samples the indium composition in the QWs reaches the level of about 20 at.%. The local indium composition was measured through strain measurements by digital processing from the lattice fringes images taken by TEM. Cross-sectional investigations are performed in two zone axes – [] and [] – with the use of axial and off-axis illumination. During TEM investigations the formation of “false indium clusters ” of the size of 2–4 nm was observed for both samples just after 2 min of LaB6 electron beam illumination at 200 kV. Large lateral fluctuations of indium content in the QWs of the length of 30–130 nm were detected in 2T sample. The plan view analysis was carried out to characterize the anisotropy of the indium fluctuation inside the QWs.

The stopping power values of 89 Y ions in carbon, nickel and gold were measured with accuracy to better than 5% in the energy range from 0.03 to 8.2 MeV/u. The newly developed B-TOF method was used for the measurements. The results are compared with theoretical and semi-empirical predictions. For this ion/absorber combination no prior experimental data are available.

This paper gives an overview of the development of an environmental-friendly small bipropellant rocket engine at the Institute of Aviation in Warsaw, Poland. 98% concentration hydrogen peroxide oxidizer and Jet-A fuel are used. A reliable pressure-fed system was chosen and system assembly tests are on-going. The final goal is to enable building and flight-qualifying a larger engine, possible to be used as a large satellite thruster and orbit transfer propulsion system. The paper covers the design and tests of a sub-scale, high contraction ratio, 250-Newton-thrust rocket engine. Fuel is injected into the oxidizer gaseous catalytic decomposition products and pseudo-hypergolic ignition occurs. Results of test firings are presented, with thrust, pressure and temperature measurements given. Special attention is drawn to the process of kerosene autoignition. A novel investigation of kerosene autoignition for very low O/F values, when a high contraction ratio is utilized, was made.

9 pags.; figs., © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Due to the development of novel manufacturing technologies and the increasing availability of nano-/micromaterials, plasmonics has become an emerging field in photonics research. Although the fabrication of metallic elements has already been widely demonstrated, the development of 3D plasmonic materials is progressing slowly. This paper reports the development of a self-organized, 3D nanoplasmonic eutectic composite that exhibits localized surface plasmon resonance at 595 nm. This eutectic composite is produced by directional solidification with the micro-pulling-down method and consists of a 3D, multiscale network of silver, nanometer-thick, micron-long sheets, and triangular cross-section microprecipitates embedded in a crystalline bismuth oxide matrix. Annealing at 600 °C further refined the structure and introduced metallic nanoparticles that exhibited plasmonic resonance in the optical region of the spectrum. This is the first demonstration of plasmonic behavior in a eutectic-based composite, which is engineered specifically for this purpose using a self-organization mechanism., he authors thank the Maestro Project (2011/02/A/ST5/00471) and the Preludium Project (2012/07/N/ST5/02428) from the National Science Centre, the Project operated within the Foundation for Polish Science Team Programme cofinanced by the EU European Regional Development Fund and the AFOSR Project 14RT0477: NOE Novel metamaterials and plasmonic materials properties enabled by the directional Eutectic solidification for support of this work.

Palladium nanograins placed in carbonaceous matrix shows many interesting properties connected to ability of hydrogen adsorption/absorption. Carbonaceous-palladium (C-Pd) films based on these materials change their structure and form, electrical conductivity, capacitance as well as optical absorption, transmission and reflection properties. These effects are connected to an incorporation of hydrogen atoms into palladium lattice [1], what change not only lattice constant [2] but also electric [3] and optical [4] properties of resulting material.

Structural, topographical and morphological changes of carbonaceous-palladium (C-Pd) films obtained by physical vapor deposition /chemical vapor deposition (PVD/CVD) method were studied. Effect of changes in these properties under the influence of CVD process temperature on the hydrogen sensitivity of these films is discussed. Scanning electron microscopy (SEM) observations were used to investigate the topography and morphology of an initial (PVD) film and the film modified in CVD process (PVD/CVD film) at different temperatures. The changes of film’s morphology after modification performed at various temperatures (500, 550, 600, 650, 700 and 750°C) caused changes in their resistance. The electrical measurements carried out in the presence of gas containing 1vol % of hydrogen showed different sensing characteristics for various films. The highest hydrogen sensitivity and the fastest response were observed for films modified at the temperature of 500°C and 550°C. In SEM images on surface of these films palladium nanograins with different sizes were observed. For films modified at the temperatures higher than 600°C Pd nanograins placed under superficial very thin carbonaceous layer were found.

Molecular beam epitaxy growth and basic physical properties of quaternary AlInGaN layers, sufficiently thick for construction of electron blocking layers (EBL), embedded in ternary InGaN layers are presented. Transmission electron microscopy (TEM) measurement revealed good crystallographic structure and compositional uniformity of the quaternary layers contained in other nitride layers, which are typical for construction of nitride based devices. The AlInGaN layer was epitaxially compatible to InGaN matrix, strained, and no strain related dislocation creation was observed. The strain penetrated for limited depth, below 3 nm, even for relatively high content of indium (7%). For lower indium content (0.6%), the strain was below the detection limit by TEM strain analysis. The structures containing quaternary AlInGaN layers were studied by time dependent photoluminescence (PL) at different temperatures and excitation powers. It was shown that PL spectra contain three peaks: high energy donor bound exciton pea...

Magnetic N-benzyl-O-carboxymethylchitosan nanoparticles were synthesized through incorporation and in situ methods and characterized by Fourier transform infrared spectroscopy, X-ray diffraction, differential scanning calorimetry, and magnetization measurements. Indomethacin was incorporated into the nanoparticles via the solvent evaporation method. The indomethacin-loaded magnetic nanoparticles were characterized by the same techniques, and also by transmission electron microscopy. The nanoparticles containing the polymer showed a drug loading efficiency of between 60.8% and 74.8%, and the magnetic properties were not significantly affected by incorporation of the drug. The in vitro drug release study was carried out in simulated body fluid, pH 7.4 at 37°C. The profiles showed an initial fast release, which became slower as time progressed. The percentage of drug released after 5 h was between 60% and 90%, and the best fitting mathematical model for drug release was the Korsmeyer-Peppas model, indicating a Fickian diffusion mechanism.

We present the nanocomposite carbonaceous-palladium (C-Pd) thin films prepared by physical vapor deposition (PVD) and chemical vapor deposition (CVD) methods. Scanning electron microscope (SEM) and transmission electron microscope (TEM) methods were used to study the topography, morphology and structure of carbon and palladium nanograins contained in these films. The quantitative analysis of the elemental composition of C-Pd films was determined by energy-dispersive spectroscopy (EDS). The initial PVD films were modified in a CVD quartz reactor using xylene (the mixture of isomers) as a modifying factor at different times (5, 10 and 30 minutes) at a constant temperature of 650°C in atmospheric pressure. It was observed that the average size of palladium nanograins increased with an increasing duration of modification process. The differences in microstructures observed in the CVD films modified at different times, affect their response in measurements of resistance changes in the gas containing H2 in various concentrations. All samples were measured by cathodoluminescence (CL) method. In CL studies a large amount of objects with high intensity of CL was found. Some of them show the emission bands both at 450 nm and 750 nm. Other reveals emission band only at 450 nm. CL observations show that Pd nanograins coated by graphite shells exhibit optical activity.

Carbon–palladium composites have been investigated by the method of transmission electron microscopy. The composites have been obtained by two different processes: physical vapor deposition (PVD) and chemical vapor deposition (CVD). The relation between the average size of a palladium particle, the time, and temperature has been carried out. The samples were annealed at different temperatures—from $$500\,^{\circ }\hbox {C}$$ to $$750\,^{\circ }\hbox {C}$$ but also for three different times, that is, 5 min, 10 min, and 30 min. Activation energies were calculated from the Arrhenius equation. Obtained values for PVD and PVD/CVD samples are: $$64.6\,\hbox {kJ}{\cdot }\hbox {mol}^{-1}$$ and $$38.8\,\hbox {kJ}{\cdot }\hbox {mol}^{-1}$$ , respectively. Determination of the activation energy will be useful in controlling the growth of palladium grains. Significant differences in values for both series resulted from encapsulation in graphite–palladium particles, which were obtained in the PVD/CVD process. Those graphite planes are formed at temperatures above $$600\,\,^{\circ }\hbox {C}$$ and significantly slow down the growth of palladium particles.