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The structure and optic properties of the transparent PP+SiO2 nanocomposites with a relatively high refractive index and enhanced luminescence properties were investigated. X-ray analysis, Fourier-transform infrared (FTIR), Visible-ultraviolet, and photoluminescence spectroscopic methods were used for investigation. The XRD analysis indicated that the fraction of the amorphous phase of the polycrystalline polymer decreases with the introduction of SiO2 nanoparticles. Even though SiO2 nanoparticle is amorphous itself, they play the role of the crystallinity centers in the polymer matrix, and the degree of crystallinity increases in polymer nanocomposites. According to UV-vis spectroscopic analysis that, with the increasing of the concentration of SiO2 nanoparticles distributed in the polymer matrix, the absorption intensity of the samples also increases. It was explained by the hyperchromic effect which is related to raising the optical density of the polymer by introducing the filler particles (SiO2). It was calculated bandgap energy and refractive index on the base of the UV spectra of samples. It has been found that at low concentrations of amorphous silica nanoparticles, the polymer nanocomposite retains its transparency despite having a relatively high refractive index (1.96). Furthermore, the photoluminescence (PL) spectrum of nanocomposites was investigated depending on filler concentration. It was clear that the intensity of the PL spectrums increases with the increase of the filler concentration that is explained by the raising of the luminescence centers in the nanocomposite material. These luminescence centers are oxygen-deficit centers in the spatial structure of the amorphous silica nanoparticles.

PP + ZrO2 polymer nanocomposites obtained through different temperature-time modes of crystallization and exposed to electrothermopolarization were studied in this paper. Even though the preparatio...

Combined hybrid nanocomposites based on PVDF+CdS/ZnS were developed and studied. The structure of nanocomposites was characterized by XRD, SEM, EDS, UV- spectroscopic techniques. XRD analysis shows...

In the given paper were investigated photoluminescence properties of PVDF/PbS/CdS hybrid nanocomposites after thermal treatment at different temperatures (100 °C, 120 °C and 140 °C) under the vacuu...

In this study, the influence of electro-thermo-polarization (ETP) on the charge state and luminescence properties of polymer nanocomposites based on PP and nanoparticles of amorphous silicon dioxid...

This paper deals with the investigation of electric, mechanical strength variations as well as the charge density of isotactic polypropylene (PP) and ZrO2 nanoparticles obtained in various supramol...

There have been investigated dielectric properties of PP + ZrO2 based nanocomposites after exposure to an external electric field. It is shown that before E = 10 ·106 kV/m the dielectric constant (...

There have been presented investigation results of electrothermopolarization influence on electret properties and charge state of PE + PbCrO4nanocomposition. Structural change of PE + PbCrO4 nanoco...

Inorganic filler and polymer matrix based PP + SiO2 nanocomposites have been prepared by the hot pressing method. The scanning electron microscopy (SEM) and X-ray diffractometer(XRD) were used for ...

In this study, the production and the EM-wave absorption properties of the polymer nanocomposites were investigated. The two- and three-phase polymer nanocomposites on the base of the PVDF matrix, multi-walled carbon nanotubes, and magnetite nanoparticles were produced by the in-situ method. With the help of XRD and SEM methods, produced nanocomposites were analyzed. Measurement of the absorption coefficient of the nanocomposites with different filler concentrations shows that the maximum effect was obtained for the nanocomposite, with 20 wt% of MWCNT in the PVDF matrix. Very close value to maximum was also, got for a nanocomposite, which contained 10 wt% of MWCNT and 5 wt% of Fe3O4 in the PVDF matrix. These results were related to energy dissipation at the high-frequency region, depending on the components fraction in the nanocomposites.

Copper nanoparticles via chemical reduction of copper sulfate by sodium borohydride in the presence of sodium oleate stabilizing agent have been synthesized and stabilized. X-ray phase analysis has...

In given paper, were studied optical properties of nanocomposites obtained on base of PP + PbS/CdS with different concentration. The UV–Vis spectral analysis indicated that the optical band gap of the system was decreases with increasing of concentration of semiconductor nanoparticles inside the polymer. This can be explained by increasing of size of nanoparticles due to agglomeration of nanoparticles with increasing of concentration. SEM analysis of PP + PbS/CdS based nanocomposites showed that particle size in PP + 3% PbS/CdS, PP + 5% PbS/CdS, and PP + 15% PbS/CdS nanocomposites was the range of 5–10 nm, 12–18 nm, and 18–34 nm in respectively. At the same time, were investigated luminescence spectra of nanocomposites with different concentrations obtained on the base of PP + PbS/CdS. It has been established that the highest luminescence intensity is observed in nanocomposites PP + 3% PbS/CdS. This can be explained by the fact that in this concentration the luminescent centers are more active and more optimal structures are formed. At the same time, low luminescence intensity in PP + 15% PbS/CdS nanocomposites can be explained by reduction of the luminescence surface and weakening of activity of centers due to the growing size of particles by agglomerating with increasing of concentration.

In the present study, the influence of the temperature–time mode of crystallization (TTC) on the electrophysical properties of polymer-based PP + Fe3O4 nanocomposite materials was investigated. Also, the effect of the temperature-time mode of crystallization of nanocomposites on the negative magnetoresistance (NMR) effect that observed in this material was investigated. It was found that dielectric permittivity of polymer nanocomposites rises with increasing of cooling rate. The cooling rate of nanocomposites after hot-pressing also affects the NMR effect of these materials. The conductivity of the material under the influence of magnetic field improves with increasing of its cooling rate, which leads to increasing of NMR effect.

Poly(vinyl chloride) (PVC)–cadmium sulfide (CdS) nanocomposite films were successfully synthesized by ex situ solution casting method. Scanning electron microscopy showed that CdS nanoparticles are well monodispersed in the PVC matrix. From the ultraviolet (UV) spectra of nanocomposites, the width of the forbidden band for polymer nanocomposites was determined by extrapolation method. UV-visible optical spectra revealed that the optical band of nanocomposites is increased with increasing concentration of CdS nanoparticles in the PVC matrix. It was found that the band gap is 3.8 eV for PVC-3% CdS nanocomposites, 2.7 eV for PVC-5% CdS, and 2.35 eV for PVC-10% CdS nanocomposites. Photoluminescence spectrum of PVC-CdS-based nanocomposites shows two luminescent peaks at the wavelengths of 436 nm and 472 nm at the luminescence spectrum which belongs to CdS nanoparticles. Photoluminescence study shows that PVC-CdS nanocomposites exhibit a great blue shift (approximately 100 nm) compared with bulk CdS nanoparticles.

It was found that the coagulation of the Fe nanoparticles takes place when they are introduced into the polymer matrix. The increase in particle size depends on their concentration in the polymer matrix, the type and properties of polymer (polar, non-polar, viscosity, etc.), reaction mode, etc. Fe particles, coagulate when they are introduced into the polymer matrix, the oxidation of their surface layer not occur, and the magnetic size does not change, hence, does not change the magnetic characteristics. The magnetic hysteresis parameters depend on the size and concentration of the Fe particles. At the same time, have been shown that at low fields the theoretical and experimental dependence of M(H) correlate to each other very well. The hysteresis has been observed at the polarization of the nanoparticles. The increasing of nanoparticles size led to difference in theoretical and experimental values, that in the theory can be explained by acceptance of nanocluster as single domain particle and their interphase interactions are not taken into account.

In the present study, the effect of size distribution of magnetite nanoparticles in a PVDF matrix on the magnetic properties of PVDF + Fe3O4 nanocomposites was experimentally and theoretically investigated. The size distribution of nanoparticles in polymer matrix and morphology of the nanocomposites were studied by the means of scanning electron microscopy and atomic force microscopy. It was found that when the Fe3O4 nanoparticles are introduced into the polymer matrix, their coagulation takes place. The increase in the size of the particles depends on their concentration in the polymer matrix, the type of polymer (polar, non-polar, its viscosity, etc.), reaction temperatures, etc. In addition, when Fe3O4 nanoparticles are introduced into the polymer network, the oxidation of the surface layer of particles occurs and the magnetic size decreases. Consequently, the reduced magnetic properties may also be observed. The hysteresis loops have been recorded in small magnetic field range. It was found that the magnetic hysteresis parameters depend on the size and concentration of Fe3O4 nanoparticles. Theoretical calculations were compared with experimental results obtained from M(H) measurements. The reasons of differences between theoretical and experimental results have been explained.

In this article, we report about the synthesis of magnetic polymer nanocomposites comprising magnetite (Fe3O4) nanoparticles in a polyethylene (PE) matrix. The structure and composition of nanocomposite materials using scanning electron microscopy and atomic force microscopy have been studied. It has been defined that the agglomeration of nanoparticles does not occur, by increasing the volume content of nanoparticles up to 60%, and Fe3O4 nanoparticles act out like single-domain particles. It has also been revealed that nanocomposites based on PE + Fe3O4 with nanoparticle content in a polymer matrix up to 60% behave like superparamagnetic particles. It has also been revealed that the PE + Fe3O4-based nanocomposites effectively absorb the electromagnetic waves in the high frequency range of 0.1–30 GHz. It is shown that the properties of ultrahigh electromagnetic waves can be varied by varying the thickness of the nanocomposite films and the concentration of Fe3O4 nanoparticles.

The effect of submicron ferroelectric BaTiO3 particles on the dielectric and electro-optical properties of the smectic-A liquid crystal (LC) with a high negative dielectric anisotropy is investigated. It is shown that the addition of BaTiO3 particles with a weight amount of 1% reduces insignificantly the transverse dielectric permittivity component e⊥ of, but significantly increases the longitudinal dielectric permittivity component e// of the smectic-A LC. As a result, the anisotropy of the dielectric permittivity Δe = e// − e⊥ of the smectic-A LC decreases. The addition of BaTiO3 particles shifts the dispersion e⊥ toward lower frequencies. Both components of the electrical conductivity of LC colloid + BaTiO3 are an order of magnitude higher than of the pure LC. The threshold voltage of the homeotropic-planar transition of the colloid is twice smaller, and its velocity is 6 times higher in comparison with the pure LC. A simple model explaining qualitatively all results obtained is presented.

The effect of a corona discharge on the structure and photoluminescence properties of nanocomposites based on polypropylene (PP) and zirconia is studied. It is shown that polarization under the action of a corona discharge leads to a refinement of the structural elements and an increase in the photoluminescence intensity and the increase depends on the charge concentration. The amount of charges accumulated at the interface between the nanocomposite components is determined by the thermostimulated depolarization (TSD) method; it is found that, during polarization, a large number of electric charges accumulate at the interface between the PP and ZrO2 nanocomposite components. It is revealed that the interfacial charges generate a fairly high internal local field, which excites luminescence centers in the zirconia and, thereby, leads to an increase in the luminescence intensity.

In the present study, the effect of magnetite (Fe3O4) nanoparticles on the structural and dielectric properties of poly(vinylidene fluoride) (PVDF) matrix was investigated. Distribution of Fe3O4 nanoparticles in the polymer matrix has been studied by scanning electron microscopy (JEOL JSM-7600 F). The structure of the nanocomposite samples was investigated by the X-ray diffraction and Fourier-transform infrared spectroscopy. It was shown that the dielectric permittivity of PVDF + Fe3O4 nanocomposite samples was gradually increased up to 7 wt% of Fe3O4 content. Further increase in the concentration of the filler leads to decrease in the dielectric permittivity. The subsequent decrease in dielectric permittivity at higher Fe3O4 content can be explained by the increase in defects in the structure of the nanocomposite. The comparison of experimental data and the results of theoretical calculations show that the reduction in the empirical value of dielectric permittivity of the nanocomposite is obviously linked with the threshold value of filler. While calculating the theoretical value of the dielectric permittivity for the higher content of the filler, defects in the nanocomposite structure should be considered.

The influence of corona discharge on the electret and charge state of nanocomposites based on isotactic polypropylene and zirconia dioxide nanoparticles has been investigated. It is shown that in the process of polarization under the influence of corona discharge charges are accumulated at the interface.These charges create sufficiently large internal local field where polarization of dioxide zirconia nanoparticles occurs. The values of the local electric field promoting the polarization of ZrO2 nanoparticles were calculated. It was found that these values are correlated with the quantity of the surface charge density measured by the induction methods. The activation energy of maximum being responsible for a cross-border charge varies in the range of 0,84–1,1eV. By calculations it was found that the thickness of the interfacial layer increaseswith concentration of dioxide zirconia in polypropylene and receives its maximum value at concentrations of 5%.

This paper deals with an investigation on the photoluminescence (PL) properties of PP+PbS/CdS nanocomposites at different temperatures ([Formula: see text], [Formula: see text] and [Formula: see text]) under vacuum. The optical bandgap was calculated on the basis of the spectra of UV absorption and it was shown that after thermal treatment the nanocomposites optical bandgap changed. The change has been attributed to the modification of the upper molecular structure of the polymer matrix due to the thermal process. The luminescence spectra of nanocomposites before and after thermal treatment at different temperatures ([Formula: see text], [Formula: see text] and [Formula: see text]) under vacuum were also measured and discussed. A very high luminescence intensity was observed after thermal treatment at [Formula: see text] temperature. This was attributed to the luminescent centers’ increase and the optimal structure formation.

In this paper, for creating highly sensitive and high-speed devices identified a new type of composite materials-fish scales, which are natural polymers. Fish scales are mineralized layer Original Research Article Gojayev et al.; PSIJ, 6(1): 45-53, 2015; Article no.PSIJ.2015.032 46 plates between which are collagen fibers. By the methods of Atomic Force Microscope (AFM) were investigated surface microrelief in 2D and 3D scale. The frequency dependence of the dielectric constant, dielectric loss, surface density of space charges of natural composite fish scales of Kutum studied in the frequency range 0 -10 kHz. Discovered that the main mechanoreceptor units of the lateral line is neyromasty, this contains several sensitive hair cells. These hair cells are similar to the sensory cells of hearing on the receptor cells neyromasty end in the branching efferent nerve fibers. Irritants receptors are streams of water and low-frequency oscillations of the medium. It was also revealed that, in a narrow frequency range 0-1 kHz reduced and in a wide range 1-1000 kHz remains constant. Right and left side fish scales have the same dielectric characteristics. Using a spectrofluorimeter Cary Eclipse fluorescence spectrum studied the fish scale in a wavelength 200-600 nm. It was revealed that, the excitation signal wavelength 396.96, 388, 265.93 and 253.64 of the fluorescence observed at a wavelength of 541.02, 528.96, 362.00, 495.97, respectively, and the intensity of the detected fluorescence peaks almost all comparable intensity of the exciting signal Kutum fish has fluorescent properties and can be successfully used in technology.

The intensive use of engineered nanoparticles (NPs) in industrial, agricultural and household applications will very likely lead to the release of such materials into the environment, especially water ecosystems. Water plants are an integral part of ecosystems; hence their interaction with NPs is inevitable. It is important to understand the consequences of this interaction and assess its potential effects. There are different types of approaches for investigating the toxic effects of NPs on plants. Chlorophyll fluorescence (ChlF) is one of interesting biophysical methods for testing the effects NPs on plants in vivo. ChlF is a suitable technique and a very powerful tool for the in vivo studying of photochemical and non-photochemical processes within thylakoid membranes, chloroplasts, plant tissues, and whole plants. The present work reports the in vivo observation of chlorophyll a fluorescence quenching induced by the iron (Fe3O4, Fe2O3) and aluminum oxide (Al2O3) nanoparticles. Excitation and emission spectra of intact leaves of Elodea were acquired by fluorescence spectrophotometer (Cary Eclipse) at room temperature. It was shown that the intensity of the ChlF decreased in the solution of Fe3O4 and Al2O3 nanoparticles on the light. Fe2O3 affected slightly and the toxicity of nanoparticles depended on dose and exposure period. It was clear from these experiments that the given nanoparticles penetrated into the cell and might decrease the chlorophyll content of leaves.

The synthesis of nanoparticles by microorganisms is environmentally safe method. The silver nanoparticles produced by fungi is complex material having different size, shape and other properties depending on the producer. İt is necessary to study new microbial strains to synthesize silver nanoparticles with important properties. The synthesis of different stable silver nanoparticles by the mold fungi was investigated in this work. To achieve this goal different strains (isolates) of Aspergillus niger were used. The most intensive formation of nanoparticles was observed in strains Aspergillus niger BDU-A4, BDU-K8, BDU-UB1 and BDU-UB5.While examining nanoparticles the following analysis methods were used: UV-Visible Spectroscopy, Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy. Electron microscopic examination showed that the shape, size and nature of nanoparticles’ clusters were dependent on fungal strains. The shape of nanoparticles is usually circular but it may be oval like in case of nanoclusters consisting of a few spherical nanoparticles. Their size varies from 20 to 100 nm.The formation of free ellipsoidal shape nanoparticles was observed at strain of Aspergillus niger BDU-K8, that varies in the range 62,9 - 68,4 nm.

The structures and magnetic properties of the PP[Formula: see text]+[Formula: see text]Fe3O4 nanocomposites manufactured by different technological techniques were studied in this work. Polymeric nanocomposite materials based on PP[Formula: see text]+[Formula: see text]Fe3O4 were obtained by two technological methods: hot pressing and extrusion. Scanning electron microscopy (SEM) and AFM investigations of nanocomposites were carried out for structure analysis. It was found that the distribution of Fe3O4 nanoparticles in the polymer matrix for nanocomposites obtained by the hot pressing method is uniform and monodisperse. Compared to this, the heterogeneous and inhomogeneous distribution of nanoparticles in the polymer matrix for the samples that were produced through extrusion method was observed. Furthermore, the nanocomposite samples produced via the extraction method have a lower surface regularity rather than those obtained by hot pressing. M(H) and M(T) studies of polymer nanocomposite samples synthesized through both technological methods were performed. Studies have shown that for relatively low concentrated samples — PP[Formula: see text]+[Formula: see text]10% Fe3O4, the values of the saturation magnetization were close, but the magnetization of nanocomposites obtained by heat pressing was slightly higher than the other samples. This is because the samples obtained by hot pressing method are characterized by higher uniformity and structure that is called “flat packaging”.

New nanocomposite structures based on isotactic polypropylene and zirconia nanoparticles are developed; the distribution of the zirconia nanoparticles is studied by optical (Motic AE 30/31) and scanning electron microscopy (Carl Zeiss). It is shown that, during the direct introduction of nanopowders into the polymer matrix, the powder nanoparticles form cluster-like fractal structures in the form of dendrites even at the first stage of mixing of the components. The electron microscopy study of the samples shows that the developed technique for preparing nanocomposites makes it possible to obtain a homogeneous distribution of zirconia nanoparticles in the matrix of polypropylene. The dielectric characteristics of nanocomposites based on polypropylene and zirconia are studied. It is found that the dielectric permeability in PP + ZrO2 nanocomposites varies as a function of the frequency owing to the low-frequency polarization.

The results of studying the effect of electrothermopolarization on the electret properties and charge state of PE + Cr and PE + PbCrO4 composites are described. It is shown that an increase in the polarization field intensity to Ep = 5 × 106 V/m leads to an improvement in the polarization processes in the composites; at Ep > 5 × 106 V/m, the space charge concentration apparently increases, which results in the deterioration of the electret properties. The observed effect can be attributed to the repeated electron capture by deeper traps owing to the internal electric field. In addition, the intensity of the TSD peaks and therefore the number of stabilized charges for the composites polarized at high intensities are higher than for the samples polarized at low intensities.

The surface morphology of n- and p-type epitaxial films of lead manganese selenide (Pb1−xMnxSe (x = 0.01)) on barium fluoride substrates of the (111) orientation in the initial state and after exposure to gamma-radiation is studied by atomic force microscopy. It is shown that the surface relief undergoes modification in the absorbed dose region of 5 ≤ Dγ ≤ 35 kGy. The p⇔n conductivity inversion at 10 ≤ Dγ ≤ 25 kGy is found from the characteristics of the surface structures and confirmed by the electrophysical measurements. It is revealed that the radiation resistance of these films is violated at a dose above 35 kGy.

The main objectives of our study were to prepare and evaluate a biodegradable nanoparticulate system of Letrozole (LTZ) intended for breast cancer therapy. LTZ loaded thiolated chitosan (TCS) nanoparticles were prepared by emulsion-solvent evaporation method. LTZ loaded TCS nanoaprticles were characterized by infrared spectra, drug entrapment efficiency and in vitro release. The system sustained release of LTZ significantly and further investigation could exhibit its potential usefulness in breast cancer therapy. The nanoparticles of LTZ prepared from TCS - may represent a useful approach for targeting its release at its site of absorption, sustaining its release.

The paper studies the viscoelastic body described by the generalized Maxwell model. This model consists of several parallel-connected simple models of Maxwell. Assuming the interaction of atoms of the body with embedded nanoparticles leads to a change in model parameters. It is shown that with the addition of nanoparticles with a specific property, it can change the value of the deformation points of a viscoelastic body. This change depends on the number of elements.

The objective of the present study was to develop carboxymethyl starch (CMS) and dextran sulfate (DS) hydrogels that are able to efficiently encapsulate 5-,10-,15-,20-tetrakis(meso-hydroxyphenyl)porphyrin (mTHPP), a porphyrin-based PS agent. The study showed that the lifetime of the triplet state for porphyrin PS is significantly increase when encapsulate into hydrogel. In addition to the possible enhancement of ¹O₂ generation, other advantages to incorporating porphyrin-based PS agents into hydrogel include the ability to solubilize these generally hydrophobic agents, the small and uniform size of hydrogels, and potential for passive targeting of solid tumors via the enhanced permeation and retention effect decreasing systemic photosensitization. This novel type of carboxymethyl starch (CMS) hydrogel using dextran sulfate (DS) as a polyanionic polymer was developed to achieve complex coacervation for the incorporation and controlled release of an anti-angiogenesis hexapeptide, this was the first report describing the use of DS to formulate CMS based hydrogels.

The objective of the present study was to develop superparamagnetic chitosan(CS) � dextran sulfate(DS) hydrogels as a intelligent drug system for effective carrying of Chlorin E6(chn E6) photosensitizer to cancer cells. This system can be detectable by magnetic Resonance Imaging technique. The study shows that the lifetime of the triplet state for chn E6 photosensitizer is significantly increase when encapsulate into hydrogel. In addition to the possible enhancement of 1O2 generation, other advantages to incorporating chn E6 -based PS agents into hydrogel include the ability to solubilize these generally hydrophobic agents, the small and uniform size of hydrogels, and potential for passive targeting of solid tumors via the enhanced permeation and retention effect decreasing systemic photosensitization.

The variations of the charge state and the thicknesses of the polymer polyethylene interlayer in piezoceramics with different structures due to their electric treatment have been investigated. It is shown that the differences of the strength properties of the piezocompositions with various particle dimensions dependent on the field strength of the electric treatment are associated with the variation of the specific surface of the polymer interlayer. The fraction of the interfaces of the polymer matrix with the equal volume content of the piezoceramics increases with the decreasing of the dimensions of the piezoceramic particles. This leads to the increasing of the interphase interactions between the components of the composite.

The effect of the structure of the piezoceramics on the dielectric and strength properties of a composite based on polyvinylidene fluoride was studied. It is shown that the dielectric strength ɛ, tanδ, and logρv correlate as dependent on the electric field intensity during the electric treatment. It is assumed that the correlation between the electric and mechanical strength is related to a change in the physical structure of the polymer matrix and the boundary layer of the composite components. The causes for a change in the charge value as dependent on the filler’s structure are found.

The purpose of this review is to discuss and summarize some of the interesting findings and applications of modified chitosan (MCS) and their derivatives in different areas of drug delivery. This review highlights the important applications of MCS in the design of various novel delivery systems like liposomes, microspheres, microcapsules, and nanoparticles. In addition to their well-known effects on drug solubility and dissolution, bioavailability, safety, and stability, their uses as recipients in drug formulation are also discussed. This review also focuses on various factors influencing inclusion complex formation because an understanding of the same is necessary for proper handling of these versatile materials. Some important considerations in selecting MCS in drug formulation such as their commercial availability, regulatory status, and patent status are also summarized.

A novel drug delivery system for the treatment of brain tumors was formulated by methotrexate (MTX)-loaded polymeric nanoparticles (NPs) based on Glycol chitosan (GCS) and Dextran sulfate (DS). The physicochemical properties of resulting particles were investigated, evidencing the contribution of these nanoparticles for brain targeting. In vitro release of MTX was also evaluated. The GCS-DS nanoparticles have been developed based on the modulation of ratio show promise as a system for controlled delivery of the drug to the brain.

In this work, we describe the results of studying the effect of the temperature-time modes of crystallization on the structure and properties of nanocomposites based on polypropylene and cadmium sulfide prepared via electrical discharge treatment in an air medium above the breakdown strength of the air. The temperature-time modes of the crystallization and other treatment factors change the supramolecular structure of the polymer, the interfacial interactions between the components of the composites, and the thickness of the interfacial layer.

Hybrid materials, which consist of organic–inorganic materials, are of profound interest owing to their unexpected synergistically derived properties. Aluminium oxide (Al2O3) nanoparticles/polymer composites have been produced using a one-system polymer synthesis. The linear polymer, poly(methyl methacrylate) (PMMA, MW = 15,000 g/mol) and polymethacrylic acid (PMAA) are applied for the stabilization of Al2O3 nanoparticles. The Fourier transfer infrared (FT-IR) analysis data and scanning electron microscopy (SEM) image reveal that the core shell structure of Al2O3/PMMA/PMAA nanocomposites have been synthesized. The ratio of concentration of the capping polymer material to the concentration of the Al2O3 precursor could control the size of Al2O3 nanoparticles. With specific concentration of the reductant, the core–shell nanostructure could be fluctuated in order.

Magnetic nanoparticles in five plant species growing on the Apsheron peninsula have been detected by the EPR method. The EPR spectra of these nanoparticles proved to be similar to those of synthesized magnetic nanoparticles. The result demonstrated that plants are capable of absorbing magnetic nanoparticles from the soil. The accumulation of nanoparticles in plants is confirmed by the presence of a broad EPR signal whose maximum position of the low-field component changes from g = 2.38 and half-width of the signal of 32 mT at room temperature to g = 2.71 and 50–55 mT at 80 K. The intensity of the broad EPR signal for plants grown in radioactively contaminated areas (170‐220 μR/h) was substantially lower compared with plants grown on clean soil. The parameters of the broad EPR signal and its dependence on the temperature of recording were identical with those for synthetic magnetic nanoparticles. The photosynthetic activity and changes in the genome of irradiated plants by the analysis of PCR products were studied.

The purpose of this study was to examine chitosan (CS)-carboxymethyl starch (CMS) nanoparticles as drug delivery system to the colon. The 5-aminosalicylic acid (5-ASA) was chosen as model drug molecule. CS-CMS nanoparticles were formulated by a complex coacervation process under mild conditions. The influence of process variables, including the two ionic polymers, on particle size, and nanoparticles entrapment of 5-ASA was studied. In vitro release of 5-ASA was also evaluated, and the integrity of 5-ASA in the release fraction was assessed using sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The release of 5-ASA from nanoparticle was based on the ion-exchange mechanism. The CS-CMS nanoparticles developed based on the modulation of ratio show promise as a system for controlled delivery of drug to the colon.

More stringent requirements for reducing the content of aromatics have brought increasing attention to new catalysts involved in hydrotreating process. The dependence of the 2,4-dinitrotoluene hydr...

In situ polymerization of aniline was carried out of superparamagnetic (Fe3O4) nanoparticles to synthesize the middle molecular weight HCl-doped polyaniline/polyanitroaniline nanocomposites. The HCl-polyaniline/ polyanitroaniline/Fe3O4 nanocomposites have been synthesized with certain composition of Fe3O4 in the composite. Thus, the synthesized composites have been characterized by infrared spectroscopy and X-ray diffraction. The morphology of these nanocomposites was studied by scanning electron microscopy. Further, the conductivity properties have been investigated in the frequency dependence of conductivity. The presence of polarons and bipolarons is made responsible for frequency dependence of conductivity. Cole—Cole plots indicate clear shift in the distribution of relaxation times as the wt% of Fe3O4 in the polymeric matrix changes. These nanocomposites show almost symmetric semicircles of Cole—Cole plots indicating the Debye-type relaxation in their polarization response.

The main aim of this research was to develop and evaluate a multiparticulate system of Ac-poly(amidoamine)(PAMAM)(G4)-chitosan (CS) hydrogels exploiting pH-sensitive and specific biodegradability properties for colon-targeted delivery of 5-aminosalicylic acid (5-ASA). All formulations were evaluated for particle size, encapsulation efficiency, swellability, and in vitro drug release. The size of the hydrogel was found to nanorange. The integrity of 5-ASA in the release fraction was assessed using sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The CS-Ac-PAMAM hydrogel was developed based on the modulation of ratio show promise as a system for controlled delivery of drug.

Highly branched, functionalized polymers have the potential to act as efficient drug carrier systems. The aromatic polyether dendrimers are spherical, highly ordered, multibranched, nanometre-sized macromolecules having positively charged ether groups on the surface under physiological conditions. In this study, we have synthesized a kind of dendrimer/poly(2-hydroxy ethyl methacrylate) nanocomposite/5-aminosalicylic acid (5-ASA) for oral drug delivery. The aromatic polyether dendrimer (generation 2, hyperbranched polyether with -CH2OH functionality, 3,5-Dihydroxybenzoic acid core) was prepared from generation 2, hyperbranched polyether dendrimer with -COOCH3 form in excellent yield. FT-IR, 1H-NMR and DSC studies suggest that the monomer predominantly forms a complex with polyether dendrimers because of the interaction between the –CH2OH end groups of dendrimer and the –OH group of 2-hydroxyethyl methacrylate monomer.