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The aim of this study was to achieve facile sintering conditions and rapid penetration of organic substances into the structure of sintered silica network on the nano-scale in order to prepare polymer infiltrated ceramic network mimicking human enamel.Stepwise temperature programming (stepwise isothermal firing) was used to create a cohesive ceramic network containing interconnected pores, which is essential to provide polymer/ceramic dual networks. Liquid phase self-penetration, ultrasonic irradiation assisted liquid phase penetration and vapor phase penetration routes were used to infiltrate methyl methacrylate monomers and benzoyl peroxide reagent into the porous silica blocks.The use of stepwise isothermal firing route, in comparison with high temperature sintering methods, significantly reduces the time and temperature required for the preliminary preparation of the SiOThe use of inexpensive silica nanoparticles and low temperature sintering and the use of ultrasound waves to quickly and effectively penetrate methyl methacrylate monomers and increase the polymerization efficiency lead to the preparation of composites with a transparent appearance and mechanical properties similar to human tooth enamel.

Reaction between 4-hydroxy-6-methyl-2H-pyran-2-one and aldehydes with 2-methylpyridine in dioxane under catalyst-free conditions provided a simple and efficient one-pot route for the synthesis of 3...

The structure of poly aniline (PANI), poly para phenylenediamine (PpPDA), and poly benzidine (PBz) is strongly dependent on the synthesis conditions and procedure. For this reason there is an ambiguity in the proposed structure of the polymers in the literature. A density functional theory (DFT) calculation were performed to establish the structure of synthesized PANI, PpPDA, and PBz. Different structures were considered for each polymer and fully optimized. Then their electrical and optical properties were calculated. Experimental band gaps of studied polymers were obtained using cyclic voltammetry technique and compared with those calculated by DFT. Optical band gap was also obtained from UV–visible spectrum of each polymer dissolved in DMSO solvent. Optical band gap value obtained for aniline is 1.90 eV which is close to the experimental band gap value reported for emeraldine form of poly aniline. Comparing calculated and experimental HOMO–LUMO gaps decline the formation of benzoid (PPDA-a) and phenenzine (PPDA-b) structures during synthesis of PpPDA. However, the exact structure of PpPDA was recognized through comparing experimental and simulated optical properties. Calculated electronic and optical band gaps of phenanzine structure of synthesized benzidine (PBz-c) are close to those of experimental ones and are confirmed by the spectroscopic results. Obtained results show that theoretical calculations play an important role in the detection of complex polymer structures.

Introduction: It is generally accepted that groundwater is one of the most vital sources of water for drinking use in cities and rural areas. The water drawn from these sources should be sanitary, have low soluble substances, and be free of any pathogens and microorganisms. Materials and Methods: In this study, 90 wells were sampled with proper dispersion over the study area to achieve suitable estimation accuracy. Results: The assessments made based on 10-year averages of water quality in the studied plain showed that according to the Schuler and Wilcox criteria of water quality for drinking and agricultural use, the northern and southern parts of the plain have unsuitable water quality compared to central parts. Interpolation RMSE value of the Inverse Distance Weighting (IDW) model for SO4-, TDS, TH, Mg2+, Cl-, Ca2+ and HCO3- were 8.46, 2615, 246, 6.8, 38.9, 8.3 1.16 also 8.4, 2628, 750.9, 7.0, 39.8, 8.1, 8.1 (mg L-1) for Kriging, respectively. Conclusion: The cause of low groundwater quality in northern regions is the high rate of SO4-, TH, Cl-, and TDS, which are of the most important determinants of water quality for drinking. The examination of samples in the assessment of water quality for agricultural use clearly showed a higher value of EC compared to SAR.

Background. Endometriosis is a chronic and estrogen-dependent pelvic inflammatory disease, which may have various causes, such as oxidative stress. Dysmenorrhea, dyspareunia, and pelvic pain are well-known symptoms of endometriosis. The present clinical trial assessed the role of supplementation with antioxidant vitamins on the indices of oxidative stress as well as the severity of pain in women with endometriosis. Materials and Methods. We enrolled 60 reproductive-aged (15–45 years) women with pelvic pain in this triple-blind clinical trial. They had 1–3 stages of laparoscopic-proven endometriosis. The participants were randomized to group A (n = 30), given vitamin C (1000 mg/day, 2 tablets of 500 mg each) and vitamin E (800 IU/day, 2 tablets of 400 IU each) combination, or group B (n = 30), given placebo pills daily for 8 weeks. Results. Following treatment with vitamin C and vitamin E, we found a significant reduction in MDA and ROS compared with the placebo group. There was no significant decline in total antioxidant capacity after treatment. However, the severity of pelvic pain ( p value p value p value

In this study, 3,4-dihydroxy-L-phenylalanine (L-Dopa) was solvothermally polymerized to monodisperse microspheres 1 μ " role="presentation"> μ μ \mu m in diameter. Polymerization was carried out in dimethylformamide containing appropriate amounts of urea and L-Dopa at 120 ∘ " role="presentation"> ∘ ∘ ^{\circ} C for 24 h. Synthesis of the polymer in basic aqueous solution under hydrothermal conditions or via conventional heating resulted in the formation of bulky powders including irregularly shaped particles of the polymer. The morphologies of the synthesized polymers were characterized by scanning electron microscopy (SEM). The microspheres synthesized by solvothermal method (with ∼ " role="presentation"> ∼ ∼ \sim 1 μ " role="presentation"> μ μ \mu m average diameter) were clearly observable in SEM micrographs. The thermal stability of the synthesized polymer was studied by thermogravimetry and differential scanning calorimetry techniques. It was recognized that the polymer is thermally stable at more than 200 ∘ " role="presentation"> ∘ ∘ ^{\circ} C. Applicability of the polymer microspheres was investigated for catalyzing the reaction of one-pot multicomponent synthesis of dihydrofurans. Several dihydrofuran derivatives were successfully synthesized using poly L-Dopa as a novel, environmentally friendly, and efficient catalyst with efficiency of more than 90%. Poly L-Dopa is easily separated by filtration from the reaction mixture. It can be used several times without decreasing the catalyzing activity after washing by suitable solvents.

Dye sensitized solar cells (DSSCs) are a type of photovoltaic device that have received widespread attention in recent years. In comparison with silicon photovoltaic cells, DSSCs exhibit some specific advantages including easy fabrication procedures, low manufacturing cost and compatibility with flexible substrates. In spite of the advantages mentioned, from the industrial point of view, the efficiency and the long term stability of the DSSCs system have been subject of concern during the past years of development of this technology. In order to solve these problems, numerous research efforts have been devoted to the engineering and manufacturing of devices that could meet the standards of the photovoltaic cells market for various applications, but the low efficiency and stability have remained as the major challenges in development of DSSCs over the past 25 year. This review focuses on the obstacles and restrictions in the fabrication and commercialization of DSSCs. Losses-in-potential as a limiting efficiency and degradation processes are discussed and external effective factors on the stability of DSSC such as thermal and light soaking stresses, environmental conditions and issues related to the sealing have been investigated in detail. Also, commercial photovoltaic technology of DSSCs in term of efficiency, stability and lifetime is compared to the different types of photovoltaic solar cells. Results indicate that despite the many attractive features of this technology, the transition from laboratory to industry and outdoor applications has been hampered by a number of issues.

Poly (4-(2-Thienyl) benzenamine) (PTBA) and corresponding homopolymers doped with sodium dodecyl benzene sulfonate (SDBS) and dedoped polymer coatings on steel surface have been synthesized by galvanostatic method. The anticorrosion performances of PTBA and its homopolymers coatings were investigated in 3.5 wt% NaCl solution by the potentiodynamic polarization technique, Tafel test and electrochemical impedance spectroscopy (EIS). The PTBA was found to exhibit enhanced corrosion protection effect on stainless steel electrode in comparison with poly aniline (PANI) and poly thiophene (PTh) homopolymers. The corrosion rate of SDBS doped PTBA-coated steel was found ∼193 times lower than that of bare steel. Corrosion potential for uncoated steel increases (−0.506 mV versus Ag/AgCl/Cl − (sat.)) to +40 mV for SDBS doped PTBA-coated steel electrodes. The results of this study clearly indicate that the PTBA doped by SDBS has an outstanding potential to protect the steel against corrosion in a chloride ion environment.

4-(2,3-dihydrothieno[3,4-6][1,4][dioxin-5-yl) aniline, an interesting novel monomer was successfully synthesized in which α-carbon on ethylenedioxythiophene was linked to aniline at para position. The structure of the monomer was approved by infrared (IR), gas chromatography-mass spectrometry (GC-MS) and 1H nuclear magnetic resonance (1H NMR) spectroscopies. Poly (4-(2,3-dihydrothieno[3,4-6][1,4][dioxin-5-yl) aniline) and its composite with graphene were electrochemically synthesized in aqueous solution by cyclic potential sweep method. The Polymer was characterized by IR and UV–vis spectroscopies, scanning electron microscopy, cyclic voltammetry, and electrochemical impedance spectroscopy techniques. Electrochemical synthesis conditions were optimized to prepare high conducting and porous polymer so it can be efficiently used as a counter electrode in fabrication of dye sensitized solar cells. Photovoltaic experiments revealed that energy conversion efficiency of the solar cell fabricated using polymer composite (7.52%) is 21% greater than that prepared by Pt counter electrode (6.19%).

A one-pot, efficient, synthesis of six novel trans-spirocyclopropane-indanedione derivatives with high stereoselectivity has been achieved via the reaction of acetopyridinium chloride with 1,3-indandione and an araldehyde in the presence of triethylamine in acetonitrile under reflux conditions. The attractive features of the method are excellent yields and high purity, short reaction times, and easy work-up.

Present work describes the fabrication of polypropylene (PP) and expanded polytetrafluoroethylene (ePTFE) air filters with antibacterial properties and more stability against washing cycles. Silver nanowires (AgNWs) were used as antibacterial agents on the filters. Deposition of AgNWs directly on the surfaces of the PP and ePTFE resulted in the preparation of the products that their antibacterial properties were significantly reduced after a few washing cycles. In order to immobilize the AgNWs on the surface of highly hydrophobic substrates such as ePTFE and PP, sodium naphthalenide was used to modify the surfaces of the PP and ePTFE fibers. The presence of sodium naphthalenide reduces the hydrophobic properties of the fibers and therefore it can increase the bonding of AgNWs to the surface. The results of the antibacterial test showed that these modified membranes have a higher durability compared to those modified without sodium naphthalenide interfacial layer.

4-(2-Thienyl)benzenamine (TBA) was successfully synthesized by a simple method including substitution of thiophene on p -nitroaniline followed by reduction of nitro group. Structure of the synthesized monomer was verified using IR, 1 H NMR, GC–MS and elemental analysis techniques. Corresponding poly 4-(2-thienyl)benzenamine) (PTBA) was electrochemically synthesized in acidic aqueous solution by cyclic potential sweep method for the first time. Characterization of the resulting polymer was performed by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), UV–vis and IR spectroscopies, and scanning electron microscopy (SEM). Effects of pH and temperature on the electroactivity of the polymer modified electrode were investigated. The corrosion behavior of PTBA in 3.5 wt% NaCl solution was studied by potentiodynamic polarization test and electrochemical impedance spectroscopy. The PTBA was found to exhibit enhanced corrosion protection effect on stainless steel electrode in comparison with polyaniline (PANI) and polythiophene (PTh) homopolymers.

4-(2-Furyl) benzenamine (FBA), was successfully synthesized by a simple method including substitution of furan on p-nitroaniline followed by reduction of nitro group. Structure of the synthesized monomer was verified using IR, 1H NMR and GC–MS techniques. Corresponding poly(4-(2-furyl) benzenamine) (PFBA) was electrochemically synthesized in acidic aqueous and organic solutions by cyclic potential sweep method. Characterization of the resulting polymer was performed by cyclic voltammetry (CV), IR, UV–vis spectroscopy, and scanning electron microscopy (SEM). Effect of solvent on the electroactivity of the polymer modified electrode was investigated. The HOMO, LUMO levels and band gap energies of the doped and undoped form of the PFBA were calculated using UV–vis and CV data. The electrochromic properties and corrosion behavior of PFBA were studied. The electrochromic properties of the copolymer film, electrochemically coated on transparent conductive oxide, corroborate multi-color electrochromic behavior of the polymer whenever the applied potential was switched from reducing (yellow) to oxidizing status (green). The FBA polymer was found to exhibit enhanced corrosion protection effect on steel electrode in comparison with corresponding polyaniline (PANI) and polyfuran (PFu) homopolymers based on series of electrochemical measurements in 3.5 wt% NaCl electrolyte solutions.

The oxidation kinetics of the poly( N -methylaniline) was investigated in aqueous solution by chronoamperometric technique. The kinetic parameters such as rate coefficients and reaction orders of the oxidation reaction of the poly( N -methylaniline) were obtained. The rate equation for oxidation of poly( N -methylaniline) in aqueous solution was established to be R = k [ClO 4 − ] α [PNMA * ] β . The rate of oxidation is independent of concentration of H 3 O + ion. This indicates unlike polyaniline, the protons are not involved in redox process. k , α , and β depending on the pre-reduction and subsequent oxidation potentials put in the range 0.69–1.20 (mol l −1 ) 1 − α s −1 ), 2.62–3.26 and 3.13–3.18, respectively. The fractional reaction orders indicate the existence of a complex mechanism for the oxidation reaction. The results show the strong influence of cathodic prepolarization on the rate of subsequent oxidation process. The rate coefficient decreases when the constant cathodic potential of prepolarization (−200 mV) is applied for rising times from 60 to 180 s. The electrochemically stimulated conformational relaxation model (ESCR) was examined to be suitable to explain the chronoamperometric behavior of poly( N -methylaniline) in aqueous solution. Aqueous solution is a protic medium in which an interchange of anions and protons can be occurred during oxidation and reduction processes of the polymer. The experimental results proved that the interaction between water and polymer is stronger than acetonitrile and polymer. So the reduction (compaction) potential of the polymer increases in water compared with aprotic solvents such as acetonitrile.

3,4-Dihydroxy-L-phenylalanine and ethylenedioxythiophene were chemically copolymerized via an oxidative process in aqueous solution. The copolymer was used as a novel mussel-inspired electroactive binder in conjunction with a nickel-based metal organic frame work for fabrication of environmentally friendly supercapacitors. The binder, in addition to the sticking effect, contributes to electric charge storing via the redox process of catechol moieties of poly(3,4-dihydroxy-L-phenylalanine) and also the formation of a high charge-storing double layer due to the presence of poly(ethylenedioxythiophene). Cyclic voltammetry, charge/discharge measurements, and electrochemical impedance spectrometry showed that the hybrid supercapacitors based on Ni-benzidine MOF with the new electroactive binder exhibit very high specific capacitance (770 F g − 1 " role="presentation"> − 1 − 1 ^{-1} at 1 A/g) and remarkable capacitance retention of more than 94% after 1000 cycles and 86% after 5000 cycles at high current density of 5 A g − 1 " role="presentation"> − 1 − 1 ^{-1} .

The structural and electronic properties of polyaniline, polypyrrole, and poly(aniline-co-pyrrole) (Ani-co-Py) in periodic form were investigated using calculations based on density functional theory (DFT). One to three monomers of aniline and pyrrole were placed in a supercell, and the effects of dihedral angles between the monomers on the electronic properties of the polymers were explored. All polymer configurations were optimized, and the band structures and densities of states (DOSs) were calculated and compared. The band gap of each polymer was calculated as the smallest energy difference between the HOMO and LUMO bands. The results showed that both sets of homopolymers exhibit semiconducting behavior which becomes less prominent after copolymerization. A comparison of the band structures of the homopolymers and the copolymer indicated that the pyrrole in the copolymer acts as an acceptor. The projected density of states (PDOS) was examined to obtain additional insight into orbital interactions and to identify the atoms that are most influential in the electronic properties of the studied polymers.

The oxidation kinetics of the polyaniline was investigated in aqueous solutions by potential steps for different values of the experimental variables. The chronoamperometric responses present a maximum, as described by the Electrochemically Stimulated Conformational Relaxation (ESCR) model. The empirical reaction kinetics R = k[ClO 4 − ] α [pAn * (qH + )] β [H + ] −γ was corroborated from the experimental results. The kinetic magnitudes: rate coefficients, reaction orders or activation energy were obtained. The value of each of those kinetic magnitudes change as a function of the initial reduced and packed state used for the subsequent oxidation: they include quantitative structural information about the structural conformational packing state of the chains in the initial state of the material The fractional reaction order indicates, as expected, the existence of a complex mechanism for the oxidation reaction.

A new magnetic nanocomposite called MIL-100(Fe) @Fe3O4@AC was synthesized by the hydrothermal method as a stable adsorbent for the removal of Rhodamine B (RhB) dye from aqueous medium. In this work, in order to increase the carbon uptake capacity, magnetic carbon was first synthesized and then the Fe3O4 was used as the iron (III) supplier to synthesize MIL-100(Fe). The size of these nanocomposite is about 30&ndash, 50 nm. Compared with activated charcoal (AC) and magnetic activated charcoal (Fe3O4@AC) nanoparticles, the surface area of MIL-100(Fe) @Fe3O4@AC were eminently increased while the magnetic property of this adsorbent was decreased. The surface area of AC, Fe3O4@AC, and MIL-100(Fe) @Fe3O4@AC was 121, 351, and 620 m2/g, respectively. The magnetic and thermal property, chemical structure, and morphology of the MIL-100(Fe) @Fe3O4@AC were considered by vibrating sample magnetometer (VSM), thermogravimetric analysis (TGA), zeta potential, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), Brunner-Emmet-Teller (BET), and transmission electron microscopy (TEM) analyses. The relatively high adsorption capacity was obtained at about 769.23 mg/g compared to other adsorbents to eliminate RhB dye from the aqueous solution within 40 min. Studies of adsorption kinetics and isotherms showed that RhB adsorption conformed the Langmuir isotherm model and the pseudo second-order kinetic model. Thermodynamic amounts depicted that the RhB adsorption was spontaneous and exothermic process. In addition, the obtained nanocomposite exhibited good reusability after several cycles. All experimental results showed that MIL-100(Fe) @Fe3O4@AC could be a prospective sorbent for the treatment of dye wastewater.

The aim of this study is to check the effect of different morphologies of silver nanoparticles such as spherical, polygonal, disk, prism, and hierarchical on antimicrobial characteristics of cotton fabrics. Nanosilver particles have been synthesized in different morphologies. Then, the colloid nanosilver particles were applied to the cotton fabric pieces for 25 ppm by ultrasonic method in ambient temperature. Silver nanoparticles solutions were characterized by UV–visible and infrared absorption spectroscopies, scanning and transmission electron microscopies as well as antimicrobial tests which ultimately showed that non-spherical morphologies such as polygonal, prism, and hierarchical like shapes in comparison with spherical and disc morphologies exhibited stronger growth inhibitory effect against gram-negative bacterium Escherichia coli and gram-positive Staphylococcus aureus after five replicate standard washing processes. In addition, among various tested morphologies, the hierarchical like morphology...

A novel N-octyl/N-perfluorohexyl substituted pyrrole was synthesized by reacting pyrrole with octyl bromide or perfluorohexyl iodide and their polymers were formed on cotton and silk textiles to make them conductive and water-repellent. Results revealed that pyrrole has been successfully transformed to N-octyl/perfluorohexyl pyrrole and complete substitution was obtained with reaction of octyl bromide. Scanning electron microscope images demonstrated that a film of N-substituted polypyrrole is homogenously covered around the fibers. Poly N-octyl/perfluorohexyl pyrrole covered cotton and silk fabrics imposed electrical conductance and hydrophobicity properties, simultaneously. The highest CA of 147.1° was obtained in the case of poly N-octyl pyrrole coated cotton fabric.

Schottky-barrier diode devices were fabricated in a sandwich configuration with poly(pyrrole-co-indole) copolymer semiconducting films prepared by electropolymerization. Effect of different dopants of ClO4 −, BF4 −, C7H7SO3 − and [Fe(CN)6]3− on the electronic properties of the fabricated devices was followed using Ag, In, Al and Cu metal junctions. Current–voltage and capacitance–voltage characteristics were recorded for making a comparative evaluation of the electronic and junction properties of the devices. The electrical characteristics of the junctions were analyzed based on the standard thermionic emission theory. Polymer doped by ClO4 − showed lower reverse saturation currents and ideality factor but higher potential barriers and rectification ratios. Effect of dopant ions and copolymerization on the optical band gaps (E g) of the films were investigated and the optical transmissions of the doped copolymer films were measured in the wavelength range of 250–900 nm. It was shown that the energy gap of copolymers laid between those of corresponding homopolymers and polyindole (PIN) doped by [Fe(CN6)]−3 had E g less than that of polymer doped by other anions whereas E g of polypyrrole was independent of dopant ions. Also, the morphology of the polymeric films revealed the surface of the PIN doped with ClO4 − was very smooth which created a good contact with indium metal.

Background: The objective of this study is to evaluate the refractive error and oculomotor conditions of infants born by assisted reproductive techniques (ART) in patients referring to Royan Institute as well as Child Health and Development Center.Materials and Methods: In this cross-sectional study, 270 ART-exposed infants aged less than 9 months were tested by retinoscopy, fixation conditions, Hirschberg and Doll's eye maneuver.Results: The average refractive error of these infants shows hyperopic Shift +0.9±1.1 D. The average astigmatism recorded in these infants is -0.6±0.6D. The prevalence of refractive errors in these infants is myopia 6%, hyperopia 85% and emmetropia 9%. Impairment of fixation conditions, Hirschberg test and Doll's eye maneuver was respectively observed in 20.4, 1.4 and 3.7% of the studied infants.Conclusion Given the sensitivities in the visual system development process and critical period which is important for every infant in the very first months of birth, it seems that visual-ocular studies are more important in ART-exposed infants who were exposed to different factors until their birth. The results of refractive errors, fixation conditions, Hirschberg test and Doll’s head maneuver which was conducted in this study for these infants reveal that, it is likely that visual impairment in these infants is higher than the results of foreign studies. However, lack of access to population studies in infants below 1 year of age in Iran necessitates more extensive studies and follow-ups of vision of ART-exposed infants more seriously.

A magnetic metal-organic framework (MOF) composite, MIL-101(Fe)@PDopa@Fe3O4, was synthesized as the stable adsorbent for removal of methyl red (MR) and malachite green (MG) from wastewaters. A very thin film of 3,4-dihydroxy-L-phenylalanine (L-Dopa) was used as an efficient and environmentally friendly binder between Fe3O4 particles and MIL-101(Fe). Characterization of MIL-101(Fe)@PDopa@Fe3O4 was accomplished by various spectroscopic, microscopic and thermal analysis techniques. Magnetic properties of the composite were studied by vibrating sample magnetometer (VSM). Influencing factors such as pH, ionic strength, contact time, adsorbent dosage, temperature, and initial dye concentration on the adsorption ability of the MIL-101(Fe)@PDopa@Fe3O4 were investigated. The very excellent adsorption capacities (833.33 and 1250 mg/g for MG and MR, respectively) were achieved. Adsorption kinetics, thermodynamics and isotherms studies indicated that MG and MR adsorption followed Langmuir isotherm model and pseudo second-order kinetic model. The Adsorbent was successfully used to remove industrial colors from real textile wastewater. The MIL-101(Fe)@ PDopa@Fe3O4 was found to be recyclable for removal of MR and MG.

Cotton was cationized by exhaustion method using 3-chloro-2-hydroxypropyl trimethyl ammonium chloride (CHPTAC) as a cation-generating agent. Adsorption of silver nanoparticles on normal and cationized cotton was studied by exhaustion method at temperatures of 80°C and 100°C. Two exhaustion baths were used, containing nanosilver colloidal solutions stabilized by two different stabilizers and various concentrations of silver nanoparticles. Fourier-transform infrared (FT-IR) spectra of normal and cationized samples confirmed the existence of quaternary ammonium groups on cationized cellulose fibers. X-ray diffraction (XRD) patterns showed that crystallinity of the modified cellulose fibers was decreased. Scanning electron microscope (SEM) images revealed that the surface of the modified cotton was rougher than that of normal cotton. In addition, SEM images showed the presence of silver nanoparticles on the surface of treated fabric samples. The amount of silver particles adsorbed on the fabric samples was determined using inductively coupled plasma-optical emission spectrometer. Antibacterial tests were performed against Escherichia coli bacteria as an indication of antibacterial effect of samples. Cationized cotton samples adsorbed more silver nanoparticles and then had greater ability to inhibit bacteria.

The reactive diionic intermediate generated by the addition of triphenylphosphine to electron-deficient acetylenic esters or ketones was trapped by mercaptoesters such as mercaptothioglycolate or methyl 3-mercaptopropanoate to produce substituted furans, vinyl sulfides, or dithioesters.

A clean, simple, one-pot, and efficient synthesis of 1,2-dihydro-1-aryl[1,3]oxazino[5,6-f]quinolin-3-one and 1,2-dihydro-1-arylnaphtho[1,2-e]-[1,3]oxazine-3-one derivatives was accomplished in good yields via reaction between 6-quinolinol or 2-naphthol, aromatic aldehydes, and methyl carbamate in aqueous medium catalyzed by TEBA (triethylbenzylammonium chloride).

The 2:1 adducts produced in the reaction between tert-butyl isocyanide and 1,1,1-trifluoro-4-arylbutan-2,4-diones were isolated and characterized as fluorinated aminoketenimines, which undergo enolization-cyclization reactions in boiling chloroform to produce new trifluoromethylated furan derivatives.

Ag intercalated graphene nanoparticles were suspended in N, N-di-methylformamide (DMF) solution of poly(vinyl chloride) (PVC). Composite thin films were prepared by drop casting on a smooth surface followed by evaporation of the solvent. Conducting nanoparticles were uniformly decorated into the polymer matrix. Composites were characterized by UV–vis spectroscopy, SEM, EDX, TEM, and XRD techniques. Electrical, mechanical and thermal characteristics of the thin films were investigated. Electrical resistance measurements reveal that the composite layers show very low percolation threshold (0.8 wt.% of conducting phase) and maximum electrical conductivity of 4.23 × 10−5 S/cm achieve at 5.0 wt.% (3.02 vol.%) of the Ag/graphene (Ag/G) nanoparticles loading. A significant enhancement in the mechanical properties of pure PVC films was obtained with a 4.0 wt.% (2.42 vol.%) loading of Ag/G, so 422.7 % increase in Young’s modulus and an almost 320 % improvement of tensile strength were obtained. In addition the results of the thermogravimetric analysis showed that the composite thin films are thermally more stable than the pure PVC polymer layers.