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Single crystals of Creatininium hydrochloride (CTNHCl) are grown by the conventional solution growth method using Millipore water at 32 °C. X‐ray diffraction reveals that it crystallizes in a monoclinic with a space group of P21/n. Solubility studies are performed at different temperatures. Intermolecular interactions involving distinct molecular moieties are also studied by mapping the 3D Hirshfeld surface and its fingerprint plots. Using FT‐IR, spectral analysis is identified. The optical efficiency of the material is studied using UV–vis–NIR and photoluminescence studies. SEM and EDAX analysis are performed for the title compound. Thermal behavior is analyzed, and the material started to melt at 275 °C. Third‐order nonlinear properties of the material like β, n2, χ(3) values are calculated using the z‐scan technique. [ABSTRACT FROM AUTHOR]

In this paper, Phoenix dactylifera L. date palm seeds (RDS) were first characterized from a physicochemical point of view, in particular the proximate and ultimate composition, XRD, and SEM–EDX analyses. Based on findings RDS contains 77.4 % of total carbohydrates, 12.8 % of lignin, and a higher heating value (HHV) of 15.88 MJ kg−1. Immuno‐labeling intensity (OD) of non‐cellulosic RDS fraction was also determined thanks to the ELISA technique after the dissolution of polysaccharides in ionic liquid showing the presence of mannans and xyloglucans and the absence of arabinans in date seeds, a significant amount of homogalacturonans were also detected. The thermal decomposition and kinetic of date palm seeds (RDS) using TGA‐DTG, and DSC measurements were then investigated. The RDS samples were heated in the temperature ranges 25–600 °C at 5, 10, 15, and 20 °C/min. The decomposition of hemicelluloses, cellulose, and lignin, active pyrolysis of RDS, was held in a range of temperature 160–450 °C. The kinetic parameters such as activation energy (Ea) and pre‐exponential factor (A) were determined for two degradation steps by using iso‐conversional model‐free methods. The Ea and pre‐exponential factor obtained by the Kissinger method are 212 kJ mol−1 and 7.8×1019 min−1 for the first decomposition interval (I1) and 172 kJ mol−1 and 5.96×1013 min−1 for the second decomposition interval I2. The same average parameters calculated by model‐free methods are 126–156 kJ mol−1 and 180–213 kJ mol−1 and 3.36×1014 and 7.07×1017 min−1 respectively for the first and second intervals of thermal decomposition. Indicating that activation energy decreases in the final stages of the process and that the energy required for hemicelluloses degradation is lower than that of cellulose. The most probable reaction functions have been determined for these two stages, by Coats‐Redfern (CR) and Criado methods, leading to considerably improved calculation performance over the entire conversion range. The pyrolysis reaction models of RDS are described by reaction, second order F2 for cellulose and hemicelluloses. With the Arrhenius parameters obtained from the fitting model of CR, we attempt to reconstruct the temperature‐dependent mass conversion curves and have resulted in generally acceptable results. Based on the Arrhenius parameter values, obtained by the Kissinger equation, the changes in entropy, enthalpy, Gibbs free energy, and lifetime predictions have been estimated for the thermal degradation processes of RDS. [ABSTRACT FROM AUTHOR]

The present investigation is mainly aimed to characterize the cellulosic fibers extracted from the stem of Shwetark plant to test its possibility to be used as polymeric reinforcement. Chemical analysis conducted on the Shwetark fibers shows the presence of cellulose (69.65 wt. %), lignin (16.82 wt. %), wax (0.53 wt. %), ash (3.4 wt. %) and wetness content (8.8 wt. %). The density of the fibers is found as 1.364 g/cm3. Crystallinity index and the crystallite size of the fibers are calculated as 72.06% and 3nm, respectively, from X-ray diffraction analysis while the presence of functional groups is ascertained from Fourier transform infrared analysis. Thermogravimetric analysis shows that the fibers are thermally stable till 225°C, and the fiber morphology seen through scanning electron microscopic shows that the fibers are composed of densely and uniformly packed cellulose microfibrils. Atomic force microscopic studies exemplify that Shwetark fibers can be used for tribological applications. The mean tensile strength and percentage elongation of the Shwetark fibers are found as 309.68 MPa and 1.092%, respectively. Thus, the studies show the possibility of Shwetark fibers as prospective candidates to replace harmful synthetic man-made fibers.

The present investigation is mainly aimed to characterize the cellulosic fibers extracted from the stem of Shwetark plant to test its possibility to be used as polymeric reinforcement. Chemical analysis conducted on the Shwetark fibers shows the presence of cellulose (69.65 wt. %), lignin (16.82 wt. %), wax (0.53 wt. %), ash (3.4 wt. %) and wetness content (8.8 wt. %). The density of the fibers is found as 1.364 g/cm3. Crystallinity index and the crystallite size of the fibers are calculated as 72.06% and 3nm, respectively, from X-ray diffraction analysis while the presence of functional groups is ascertained from Fourier transform infrared analysis. Thermogravimetric analysis shows that the fibers are thermally stable till 225°C, and the fiber morphology seen through scanning electron microscopic shows that the fibers are composed of densely and uniformly packed cellulose microfibrils. Atomic force microscopic studies exemplify that Shwetark fibers can be used for tribological applications. The mean tensile strength and percentage elongation of the Shwetark fibers are found as 309.68 MPa and 1.092%, respectively. Thus, the studies show the possibility of Shwetark fibers as prospective candidates to replace harmful synthetic man-made fibers. [ABSTRACT FROM AUTHOR]

The yttrium citrate was synthesized using freshly precipitated yttrium hydroxide and citric acid (or monosodium citrate) in the aqueous environment by the hydrothermal treatment at 80 °C or 100 °C. The properties of the samples were investigated using the CHN, XRD, TGA and static light scattering. Crystalline yttrium citrate dihydrate is formed by the reaction of citric acid with freshly precipitated yttrium hydroxide after 14 days of reaction at 80 or 100 °C. The thermogravimetric analysis of the crystalline sample of yttrium citrate dihydrate, thermal decomposition of the compound in the synthetic air occurs in four stages with the release of mainly water and carbon dioxide. Methane and propyne are formed in smaller amounts. [ABSTRACT FROM AUTHOR]

The asymmetric unit of the title compound, C12H22N+·CH3O3S−, consists of three (3,5-dimethyladamantan-1-yl)ammonium cations, C12H22N+, and three methanesulfonate anions, CH3O3S−. In the crystal, the cations and anions associate via N—H...O hydrogen bonds into layers, parallel to the (001) plane, which include large supramolecular hydrogen-bonded rings.

In this work, low-cost non-conventional nanostructured Fe2O3 was produced by a modified low-temperature urea method (MLTUM-Fe2O3). Non-magnetic amorphous nanoparticle MLTUM-Fe2O3 with a bouquet like morphology is found to play as an effective sorbent media to remove textile dye Reactive Blue 19 from textile industries dye effluents over a wide range of pH. The nanoparticles were characterized by X-ray powder diffraction analysis (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), FTIR and TGA. The surface area was measured by Brunauer-Emmett-Teller (BET) analysis. SEM image reveals bouquet like morphology with average particle size about 50 nm. The maximum sorption capacity of the sorbent is found to be 271.00 mg g-1 for Reactive Blue 19 and the data fitted with different isotherm models. Study on sorption kinetics shows that sorption of Reactive Blue 19 onto iron oxide follows pseudo-second-order kinetic. [ABSTRACT FROM AUTHOR]

The asymmetric unit of the title compound, C12H22N+.CH3O3S-, consists of three (3,5-dimethyladamantan-1-yl)ammonium cations, C12H22N+, and three methanesulfonate anions, CH3O3S-. In the crystal, the cations and anions associate via N--H···O hydrogen bonds into layers, parallel to the (001) plane, which include large supramolecular hydrogen-bonded rings. [ABSTRACT FROM AUTHOR]

ABSTRACT: The polymer/multiwalled carbon nanotube [poly(vinyl alcohol) (PVA)/carboxyethyl acrylate (CEA)]‐multiwalled carbon nanotube (MWCNT) and its amino functionalized (PVA/CEA)‐MWCNT‐NH2 nanocomposite samples were successfully synthesized by the chemical method in the form of films. The samples were irradiated with gamma‐ray doses of 50 and 100 kGy and with ion beam fluence of 2.5 × 1018 and 3.75 × 1018 ions cm−2. The prepared nanocomposite samples were characterized using X‐ray diffraction and thermogravimetric analysis. The X‐ray diffraction and thermogravimetric analysis confirm the existence of the chemical crosslinking occurred in the polymer compositions. The AC electrical conductivity, electrical modulus, dielectric constant, and dielectric loss in the frequency range 102–106 Hz are measured at room temperature. The electrical conductivity is increased with MWCNT doping, gamma‐irradiation, and by ion beam irradiation. A comprehensive analysis of the results revealed that dielectric properties are improved due to the induced physicochemical changes and conductive networks induced by ion beam irradiation. The behavioral effect of these embedded nanoparticles in a PVA matrix on the microstructural, dielectric, and electric properties is analyzed for possible device applications. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46647. [ABSTRACT FROM AUTHOR]

Kaolinite content of 10 raw Florida clays examined in this study was determined to be in the range of 70 to 90 mass %. This kaolinite content is sufficiently high for production of a potentially reactive pozzolanic material. The majority of the clays were at least partially disordered, which also indicates good pozzolanic activity of these materials after calcination. A good fit of the collected X-ray diffractograms during Rietveld refinement was obtained by using a combination of kaolinite, nacrite and dickite structures to allow modeling of stacking faults in kaolinite, adjusting for Fe 3+ substitution and refining atomic coordinates. The results of kaolinite quantification were similar to those obtained by thermogravimetric analysis, which validates the proposed approach. Stoichiometric calculation also provided comparable results for all the clays, except for one sample where large overestimation of kaolinite content compared to X-ray diffraction and thermogravimetric analysis was observed. It was concluded that Florida clays present a promising potential source of supplementary cementitious materials for production of sustainable concrete. [ABSTRACT FROM AUTHOR]

In the present study, we have looked into the effects of the amount of the combustion fuel of urea on the morphological, thermal and morphological properties of MgO structure. To this goal, three Magnesium Oxide (MgO) samples were synthesized by the combustion method and the as-mentioned properties were characterized by the experimental analysis techniques of X-Ray Diffraction (XRD), Differential Thermal Analysis (DTA), Thermogravimetric Analysis (TGA) and Scanning Electron Microscopy (SEM). The functional groups in the samples were also determined using Fourier Transform Infrared (FTIR) spectrometry. The crystallinity percent values for each sample were found to be about in the range of 94–96%. The crystallite sizes of the samples were computed to be in the ranges of 26–37 nm and 23–32 nm for Scherrer and Williamson-Hall methods, respectively. The increasing quantity of urea caused a gradual growth in the lattice parameter of Magnesium Oxide structure. The thermal properties and morphology were affected by the urea content. [ABSTRACT FROM AUTHOR]

ABSTRACT Novel polyaniline (PANI)/flowerlike CuS composites with improved electromagnetic interference (EMI) shielding effectiveness (SE) were prepared through the in situ polymerization of PANI into the flowerlike CuS microspheres. X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, ultraviolet-visible optical absorption spectroscopy, thermogravimetric analysis, electrical conductivity testing, and EMI SE testing were used to characterize the as-obtained products. The results reveal that the flowerlike CuS was uniformly coated by a PANI shell. Most importantly, compared with the original CuS and pure PANI, the novel PANI/flowerlike CuS composites exhibited a remarkably enhanced SE. With a thickness of 3 mm, the optimal EMI SE of the PANI-CuS composites reached −45.2 dB at 2.78 GHz, and an improved shielding efficiency below −18 dB was also obtained over the frequency range from 300 kHz to 3 GHz. This suggested that these novel PANI/flowerlike CuS composites have promising applications in the field of shielding materials. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45232. [ABSTRACT FROM AUTHOR]

In this study, polypyrrole (PPy)/carbon nanotube (CNT) composites were synthesized by in situ chemical oxidative polymerization of a pyrrole monomer on CNT. Two different types of CNT having different structural properties were used. The composites were characterized using BET surface area analysis, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA) techniques. Thermal decomposition kinetics of PPy/CNT composites was studied by thermal gravimetric analysis techniques (TG/DTG (differential thermal gravimetric)) at different heating rates (2.5, 5, 7.5, and 10 K min-1). Kinetic parameters of the composites were obtained from the TG and DTG curves using the Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO) models. The electrochemical capacitive properties of the composites were investigated by the cyclic voltammetry (CV) technique. Pt nanoparticles were decorated on the plain CNTs and composite materials via the microwave irradiation method. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the potential of nano-clays as active and intelligent (A&I) food nanopackaging materials. Nanopackaging is a structured system that allows the storage of certain compounds in a stable form. Nano-clays were prepared from natural and modified montmorillonite (Mnt) with and without added blueberry extract, and characterized in terms of their: X-ray diffraction (XRD) patterns, thermogravimetric (TGA) properties, microstructure, moisture content, water activity ( a w ), infrared spectra (FTIR), Raman spectra, color parameters, response to pH changes, and antioxidant and antimicrobial activity. Mnt prepared with added blueberry extract showed antioxidant activity and intelligent behavior under different pH conditions. Modifying the Mnt increased the interlayer spacing, thus allowing more blueberry extract to be incorporated within the system. In conclusion, natural and modified Mnt are eco-friendly resources with potential applications for nano-packaging. The addition of blueberry extract imparted intelligent properties to the nano-clays as regards their responses to changes in pH. [ABSTRACT FROM AUTHOR]

Electrically conductive polypyrrole-zirconium( IV) phosphate (PPy-ZrP) cation exchange nanocomposites have been synthesized for the first time by in situ chemical oxidative polymerization of pyrrole in the presence of zirconium(IV) phosphate (ZrP). Fourier Transform Infra-red spectroscopy (FTIR), field emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, thermogravimetric analysis, differential thermal analysis, derivative thermogravimetry and elemental analysis were used to characterize PPy-ZrP cation exchange nanocomposite. The composite showed good ion-exchange capacity (1.60 meq g-1), DC electrical conductivity (0.33 S cm-1) and isothermal stability in terms of DC electrical conductivity retention under ambient condition up to 100 °C. PPy-ZrP cation exchangenanocomposite- based sensor was fabricated for the detection of ammonia vapours of aqueous ammonia. The resistivity of the nanocomposites increases on exposure to high-concentration ammonia vapours at room temperature (25 °C). The rate of reaction for ammonia vapour-sensing on PP-ZrP was observed as second order. [ABSTRACT FROM AUTHOR]

A new organic stilbazolium derivative, 1-Ethyl-2-(2- p -tolyl-vinyl)-pyridinium iodide (TASI), was grown from methanol:acetonitrile (1:3) mixed solvent by slow evaporation technique. Single crystal X-ray diffraction analysis revealed that TASI crystallizes in triclinic system with a centrosymmetric space group P-1. The molecular structure and the presence of expected functional groups of TASI were confirmed by 1 H NMR and FT-IR spectroscopic studies. The HOMO and LUMO energies influence the charge transfer takes place within the molecule. The grown crystal was thermally stable up to 210 °C as determined by TG/DTA analysis. UV-Vis-NIR spectral study showed that the grown crystal was transparent in the wavelength range of 438–1100 nm. Mechanical behaviour and surface laser damage threshold were studied to find the suitability of the grown crystal for device fabrication. Studies of its third-order nonlinear optical properties using a Z-scan technique demonstrates that TASI crystal is capable of exhibiting reverse saturable absorption and self-focusing performance with the second-order molecular hyperpolarizability (γ) 4.983 × 10 −34 esu. The third-order nonlinear susceptibility of TASI was found to be 8.931 × 10 −6 esu, which is higher than a few other stilbazolium derivative crystals. [ABSTRACT FROM AUTHOR]

BaFe 0.9-x Y 0.1 Co x O 3-δ (0 ≤ x ≤ 0.15) is shown to adopt the cubic perovskite structure at temperatures up to 1400 K in air. The oxygen vacancy concentration increases with both cobalt content and temperature, with BaFe 0.75 Y 0.1 Co 0.15 O 2.35 being the most oxygen-deficient composition observed. At 700 K the conductivity is ∼2 S cm −1 across the whole composition range. Measurements of the Seebeck coefficient show that holes are the dominant carrier. The coefficient of thermal expansion is essentially constant above 800 K, but not at lower temperatures. Chemical reactivity tests, along with the coefficient of expansion, show that these perovskites would not be suitable electrodes for fuel cells with fluorite electrolytes but they might serve as permeable membranes in catalytic reactors. [ABSTRACT FROM AUTHOR]

Lithium ferrite was prepared by the thermal decomposition of three polynuclear complex compounds containing as ligands the anions of malic, tartaric and gluconic acid: (NH4)2[Fe2.5Li0.5(C4H4O5)3(OH)4(H2O)2]×4H2O (I), (NH4)6[Fe2.5Li0.5(C4H4O6)3(OH)8]×2H2O (II) and (NH4)2[Fe2.5Li0.5(C6H11O7)3(OH)7] (III). The polynuclear complex precursors were characterized by chemical analysis, IR and UV–Vis spectra, magnetic measurements and thermal analysis. The obtained lithium ferrites were characterized by XRD, scanning electron microscopy, IR spectra and magnetic measurements. The single α-Li0.5Fe2.5O4 phase was obtained by thermal decomposition of the tartarate complex annealed at 700 °C for 1 h. The magnetization value ≈ 50 emu g-1 is lower than that obtained for the bulk lithium ferrite due to the nanostructural character of the ferrite. The particle size was smaller than 100 nm.

Lithium ferrite was prepared by the thermal decomposition of three polynuclear complex compounds containing as ligands the anions of malic, tartaric and gluconic acid: (NH4)2[Fe2.5Li0.5(C4H4O5)3(OH)4(H2O)2]×4H2O (I), (NH4)6[Fe2.5Li0.5(C4H4O6)3(OH)8]×2H2O (II) and (NH4)2[Fe2.5Li0.5(C6H11O7)3(OH)7] (III). The polynuclear complex precursors were characterized by chemical analysis, IR and UV-Vis spectra, magnetic measurements and thermal analysis. The obtained lithium ferrites were characterized by XRD, scanning electron microscopy, IR spectra and magnetic measurements. The single a-Li0.5Fe2.5O4 phase was obtained by thermal decomposition of the tartarate complex annealed at 700°C for 1 h. The magnetization value ≈ 50 emu g-1 is lower than that obtained for the bulk lithium ferrite due to the nanostructural character of the ferrite. The particle size was smaller than 100 nm.

We report the studies on composite gel polymer electrolytes (GPEs) comprising 0.5 M solution of sodium trifluoromethane sulfonate (Na-triflate or NaTf) in ionic liquid 1-ethyl 3-methyl imidazolium trifluoromethane sulfonate (EMITf) entrapped in poly (vinylidinefluoride-co-hexafluoropropylene) (PVdF-HFP) dispersed with passive filler AlO and active filler NaAlO particles. The free-standing films of the composite GPEs, prepared from solution-cast method, offer optimum ionic conductivity at room temperature (6.3-6.8 × 10 S cm and 5.5-6.5 × 10 S cm for AlO- and NaAlO-dispersed GPEs, respectively), with sufficient electrochemical stability and excellent thermal stability up to 340 °C. As observed from XRD and SEM, the composites are of predominantly amorphous and porous character, which support the high ionic conduction. The sodium ion transport number has been found to be ∼0.27 for AlO-dispersed GPE and 0.42 for NaAlO-dispersed GPE, which indicates the predominant role of passive and active fillers, AlO and NaAlO, respectively. The dispersion of NaAlO enhances the sodium ion conductivity in composite GPE substantially. The overall ionic conductivity is same as in the case of AlO dispersion. The performance characteristics of GPE, particularly, dispersed with active filler NaAlO show its potential applicability as electrolyte/separator in sodium batteries. [ABSTRACT FROM AUTHOR]

The reaction of l -arginine and oxalate ions with copper(II) salts yields a new complex with formula of [Cu(L-Arg) 2 (H 2 O)]·C 2 O 4 ·6H 2 O ( 1 ) (where L-Arg = L-arginine). Single crystals of 1 were synthesized by crystallization from aqueous solution. The complex properties were characterized by X-ray diffraction, spectroscopy (FT-IR, FT-Raman, NIR-Vis-UV and EPR) as well as thermal and magnetic methods. The square pyramidal (SP) geometry around Cu(II) ions in [Cu(L-Arg) 2 (H 2 O)] 2+ cation complex is formed by two cis- chelated l -arginine zwitterions and a water molecule coordinated in the apex of square pyramid. The trigonality distortion of SP geometry is relatively small, τ = 0.0087. The solid state EPR spectrum showed broad hyperfine splitting with g ⊥ = 2.061 at 77 K. The copper centres distanced at 7.558(5) Å are joined in a single zig-zag structure via a chain based on the combination of Cu O(5) H(29)⋯O(2) C1 O1 Cu hydrogen bonds along the b axis ( d (O2⋯O5) = 2.812 Å). Taking into account the structural features, the magnetic susceptibility data were best-fitted, giving the exchange parameter J = −0.16 cm −1 . Complex 1 is thermally stable up to 66 °C, where it was observed to lose the crystallization water molecules with an 11.7% mass loss ( calc. 11.5%). [ABSTRACT FROM AUTHOR]

The nickel phosphorous catalyst coating was studied on the E-glass fiber by electroless deposition using sodium hypophosphite as a reducing agent in alkaline medium. The effects of deposition time, deposition temperature, pH of the solution, and amount of stabilizer used in the solution on the coating efficiency were investigated by X-ray diffraction (XRD), energy dispersive X-ray analysis (EDAX), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and differential thermal analysis (DTA). The XRD indicates the presence of amorphous and crystalline phases of Ni and nickel–phosphorous (NiP). From TGA, it is evident that the NiP coating increases the thermal stability and magnetic properties of the glass fiber. The bath temperature of 80 °C, pH of 9 to 9.5, and stabilizer concentration of 25 g/l are optimum to get a good and uniform coating of NiP on glass fiber. Carbon nanotubes were successfully coated on NiP coated glass fiber at a temperature of 700 °C. [ABSTRACT FROM PUBLISHER]

Four inks for the production of ZnO semiconducting films have been prepared with zinc acetate dihydrate as precursor salt and one among the following aminoalcohols: aminopropanol (APr), aminomethyl butanol (AMB), aminophenol (APh) and aminobenzyl alcohol (AB) as stabilizing agent. Their thermal decomposition process has been analyzed in situ by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and evolved gas analysis (EGA), whereas the solid product has been analysed ex-situ by X-ray diffraction (XRD) and infrared spectroscopy (IR). Although, except for the APh ink, crystalline ZnO is already obtained at 300 °C, the films contain an organic residue that evolves at higher temperature in the form of a large variety of nitrogen-containing cyclic compounds. The results indicate that APr can be a better stabilizing agent than ethanolamine (EA). It gives larger ZnO crystal sizes with similar carbon content. However, a common drawback of all the amino stabilizers (EA included) is that nitrogen atoms have not been completely removed from the ZnO film at the highest temperature of our experiments (600 °C). [ABSTRACT FROM AUTHOR]

Three dimensional, flower-like hierarchical porous carbon (FPC) and its CO 2 -activation (AFPC) are reported as sulfur-hosting matrixes in Li/S battery. The composites are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), nitrogen adsorption-desorption isotherms as well as by galvanostatic cycling and electrochemical impedance spectroscopy (EIS) in lithium-cell. Both samples show well defined micrometric morphology and a sulfur content as high as 66% expected to reflect into rather high practical energy density of the electrode in lithium-sulfur battery. The lithium sulfur cell using the FPC-S composite exhibits at 25 °C a moderate cycling stability with delivered capacity ranging from 1000 to about 610 mAh g −1 upon 50 cycles at 100 mA g −1 . The AFPC-S composite reveals increased cycling stability and delivers a capacity ranging from 1000 to 680 mAh g −1 . Improved capacity is achieved by slightly increasing the temperature, as demonstrated by cycling the FPC-S at 35 °C using a current as high as 500 mA g −1 . The excellent rate capability of the electrode is associated to the carbon texture and morphology that significantly lower the cell resistance, as indeed demonstrated by EIS measurement upon cycling. [ABSTRACT FROM AUTHOR]

We synthesized one dimensional (1-D) AlN whiskers by using the cobalt oxide catalyst-assisted carbothermal reduction method. The formation of AlN whiskers is investigated by the thermo-gravimetric and differential thermal analysis, Fourier-transformed infrared spectra, X-ray diffraction patterns, scanning electron microscopy and transmission electron microscopy observations. It was found that Co 3 O 4 droplets on the surfaces of Al 2 O 3 acted as a catalyst for the growth of AlN whiskers by vapor-liquid-solid (VLS) mechanism. In addition, AlN whiskers/PVA composites aligned in parallel with the heat flow direction showed an excellent thermal conductivity about three times higher than those of the perpendicularly aligned whisker composites. [ABSTRACT FROM AUTHOR]

In the present study, a simple, low cost, and ecofriendly synthesis of magnetite nanoparticles (Fe 3 O 4 NPs) has been developed using Andean blackberry leaf extract. UV–vis spectroscopy technique were used to study the initial formation of Fe 3 O 4 NPs. Morphology, crystallinity and surface properties of nanoparticles were studied using transmission electron microscopy (TEM), Dynamic light scattering (DLS), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and Thermal gravimetric (TG) techniques. TEM and DLS characterization indicated the formation of spherical Fe 3 O 4 NPs of average size 54.5 ± 24.6 nm. XRD and FTIR studies confirmed the existence of the cubic spinel phase of Fe 3 O 4 NPs and Fe O peak at 570 cm −1 , whereas TG analysis indicated that the nanoparticles contain 94% metal and 6% capping ligand. It has been observed that, as-synthesized Fe 3 O 4 NPs exhibited photocatalytic activity for degradation of organic dyes such as methylene blue (k = 0.0105475 min −1 ), congo red (k = 0.0043240 min −1 ), and methyl orange (k = 0.0028930 min −1 ), efficiently. The antioxidant activity of Fe 3 O 4 NPs against 1, 1-diphenyl-2-picrylhydrazyl were also evaluated. [ABSTRACT FROM AUTHOR]

Nanoemulsion technique was applied for synthesis of carbonated strontium hydroxyapatite (CSrHAp) at room temperature. X-ray powder diffraction analysis accompanied with Rietveld refinement reviled that synthesized powder were single-phase hydroxyapatite. Fourier transform infrared (FTIR) spectroscopy showed that the CSrHAp was A-type substitution. The carbonate amount substituting the hydroxide group in the synthesized apatite was estimated, from the corresponding CO 2 weight loss in the range 600–1100 °C. According to this empirical formula of as synthesized CHAp is Sr 10 (PO 4 ) 6 (OH) 0.60 (CO 3 ) 0.70 . These results were confirmed by the Rietveld refinement analysis. Using scanning electron microscopy analysis it was found that the synthesized CSrHAp particles were spherical in shape and that their sizes were in the nanometer range. Nanoemulsion strategy procedure provides a simple pathway to obtain single-phase CSrHAp. [ABSTRACT FROM AUTHOR]

l -Argininium hydrogen squarate (LAHS) is an organic nonlinear optical material grown by slow evaporation solution growth technique. The crystal structure was confirmed by single crystal X-ray diffraction analysis and the crystal system is identified as triclinic system. The thermal stability and decomposition process were studied by thermogravimetric analysis (TGA) and differential thermal analysis (DTA). The crystal is stable up to 238 °C. The optical transparency range and lower cut-off wavelength of grown crystal have been identified by UV–vis–NIR spectroscopy method. The existence of second harmonic generation (SHG) signal was observed using Nd:YAG laser with fundamental wavelength of 1064 nm. The SHG efficiency is compared with potassium di-hydrogen phosphate (KDP) and urea. [ABSTRACT FROM AUTHOR]

Single crystals of a new nonlinear optical material, triaquatrismalonatodicerium (III) dihydrate ([3H 2 O(C 3 H 2 O 4 ) 3 Ce 2 ]·2H 2 O), have been grown using gel aided solution growth technique. The functional groups present in the crystal are identified using FTIR spectrum. X-ray diffraction studies on single crystals showed that the compound crystallizes in the monoclinic system with a non centrosymmetric space group P 2 1 with unit cell dimensions a = 7.6795(5)Å, b = 12.9648(7)Å, c = 8.9545(5)Å, α = γ = 90°, β = 101.380(6)°. Thermogravimetric studies reveal the thermal stability and decomposition pattern of the material. The UV – vis spectrum indicates excellent transmittance in the entire visible region. Optical band gap energy of the crystal was evaluated from the diffused reflectance spectrum (DRS). Photoluminescence spectroscopy throws light on the optical emission properties. Excellent second harmonic generation (SHG) efficiency of the crystal was confirmed by Kurtz and Perry powder test. [ABSTRACT FROM AUTHOR]

Mn4+, Ce4+ and Sm3+ doped MgAl2Si2O8-based phosphors were synthesized at 1300 °C by solid state reaction and characterized by thermogravimetry (TG), differential thermal analysis (DTA), X-ray powder diffraction (XRD), photoluminescence (PL), thermoluminescence (TL) and scanning electron microscopy (SEM). The phosphors showed broad red emission bands in the range of 610-715 nm and different maximum intensity when activated by UV illumination. Such a red emission can be attributed to the intrinsic 2E→4A2 transitions of Mn4+. [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, redox-initiated free radical graft copolymerization of microcrystalline cellulose (MCC) and methyl methacrylate (MMA) has been carried out in aqueous media to develop a novel cellulose-based copolymer. Cerium ammonium nitrate was used as the initiator in the presence of nitric acid. Effects of monomer concentration, initiator concentration, polymerization time, and polymerization temperature on the graft parameters of copolymers were studied. The successful grafting copolymerization between MCC and MMA was validated through attenuated total reflection, wide-angle X-ray diffraction, field-emission scanning electron microscopy, and thermal gravimetric analysis. In comparison to native MCC, the resultant copolymers exhibited enhanced thermal stability and better compatibility with natural rubber, suggesting its potential application as reinforcement material in rubber industry. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42666. [ABSTRACT FROM AUTHOR]

Crystals of diaqua maleatocalcium (II) (CaC 4 H 2 O 4 ·2H 2 O) have been grown by the controlled diffusion of ionic species in inert hydrosilica gel. The single crystal X-ray diffraction studies reveal that the crystal belongs to orthorhombic system with non-centrosymmetric space group P 2 1 2 1 2 1 . The unit cell parameters are a = 6.849(5) Å, b = 8.665(5) Å, c = 11.002(5) Å and α = β = γ = 90.000(5)°. The functional groups present in the compound are identified from the FTIR spectrum. Thermogravimetric studies are performed to explore the thermal stability and decomposition pattern of the material. The UV – vis – NIR studies indicate wide transparency window, a befitting material characteristic for optoelectronic applications. The optical band gap of the material was estimated using diffuse reflectance spectroscopy. The second harmonic generation (SHG) efficiency possessed by the crystal is revealed by the Kurtz and Perry powder test. [ABSTRACT FROM AUTHOR]

Three zwitterionic surfactants, dodecyl dimethyl carboxylbetaine (DCB), dodecyl dimethyl sulfobetaine (DSB) and N-dodecyl-β-aminoprpionate (DAP), intercalated into NiZn-layered hydroxide salts (NZL-DCB, NZL-DSB and NZL-DAP) were synthesized by the coprecipitation method. The effect of surfactant content, pH, temperature and time of hydrothermal treatment on preparation was investigated and discussed. The NZL-DCB, NZL-DSB and NZL-DAP were characterized by powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FTIR), and thermogravimetry analysis and differential thermal analysis (TGA/DTA). The results showed that basal spacings of NZL-DCB, NZL-DSB and NZL-DAP were around 3.45, 3.68 and 3.94 nm, respectively. DCB, DSB and DAP probably form an overlapped bilayer in the gallery. TGA/DTA data indicated that NZL-DCB, NZL-DSB and NZL-DAP displayed three loss weight stages: loss of adsorbed and structural water, dehydroxylation of matrix and decomposition of nitrate ions, decomposition and combustion of surfactants. Furthermore, chemical analysis data, BET surface area and scanning electron microscopic (SEM) were also measured and analyzed. [ABSTRACT FROM AUTHOR]

Crystallization process of Gd 2 Ti 2 O 7 precursor's powder prepared by Pechini-type polymerized complex route has been studied under isothermal experimental conditions in an air atmosphere. It was found that the crystallization proceeds through two-parameter Šesták–Berggren (SB) autocatalytic model, in the operating temperature range of 550 °C≤ T ≤750 °C. Based on the behavior of SB parameters ( M , N ), it was found that in the lower operating temperature range, the crystallites with relatively low compactness exist, which probably disclosed low dimensionality of crystal growth from numerous nucleation sites, where the amorphous solid is produced. In the higher operating temperature region (above 750 °C), it was established that a morphological well-defined and high-dimensional particles of the formed pyrochlore phase can be expected. It was found that at T =850 °C, there is a change in the rate-determining reaction step, from autocatalytic into the contracting volume mechanism. [ABSTRACT FROM AUTHOR]

Aluminium-based alloys have wide applications but little is known about the thermal-chemical kinetics of nanoalloys. This work investigated the thermal oxidation of Zn and Al nanoalloys (nAlZn) with a BET equivalent diameter of 141 nm through the simultaneous TGA/DSC method. The thermal analysis was combined with elemental, morphology and crystalline structure analysis to elucidate the reaction mechanisms. It was found that the complete oxidation of nAlZn in air can be characterised by a three-stage process, including two endothermic and three exothermic reactions. With the help of ex-situ XRD, different reaction pathways were proposed for different stages, forming the end products of ZnO and ZnAl 2 O 4 . The reactivity comparison between Al and nAlZn suggested that different criteria should be used for different applications. [ABSTRACT FROM AUTHOR]

Ionic liquids (ILs) have attracted much attention in the scientific community during the past two decades. However, studies of interactions between Earth materials and ILs have been limited. In this study, the uptake and interlayer configuration of ILs on a high charge Ca-montmorillonite (MMT) were systematically studied using TG-DTG, FTIR, and XRD analyses. The intercalation protected the ILs from thermal decomposition, resulted in an increase in their thermal stability in comparison to ILs adsorbed on the surfaces. The results from TG-DTG, FTIR, and XRD all pointed to a change in mechanisms and interlayer configurations as the chain length, input amounts, and initial concentrations of ILs changed. A higher decomposition temperature in TG analyses and a large blue shift of selected FTIR bands agreed well with the cation exchange mechanism at lower IL loading levels. Accompanying cation exchange the interlayer water was completely removed. Hydrophobic interactions and admicelle adsorption were responsible for IL uptake beyond the cation exchange capacity of the MMT. A pseudo-trilayer configuration was suggested based on XRD analyses for the intercalation of ILs with a chain length of 12 carbons at the sorption maximum and that of 16 carbons at medium sorption levels. A paraffin-like conformation with an almost vertical orientation was suggested for the configuration of IL with a chain length of 16 carbons in the interlayer of MMT at the sorption maximum. [ABSTRACT FROM AUTHOR]

The processes involved in the assembly of zinc acetate dihydrate {Zn(CH 3 COO) 2 ·2H 2 O} and ethanolamine (H 2 NCH 2 CH 2 OH), with or without 2-methoxyethanol as solvent, have been analysed by infrared spectra, mass spectrometry, nuclear magnetic resonance, powder X-ray diffraction and computational studies. Thermal evolution of the mixtures was characterized by thermoanalytical and structural techniques (thermogravimetry, differential thermal analysis, differential scanning calorimetry, X-ray diffraction and X-Ray photoelectron spectroscopy). Computational studies together with experiments served to thoroughly describe the precursor and its decomposition. The thermal decomposition of the mixture and its transformation into crystalline ZnO take place in a temperature range between 50 and 450 °C through different processes. With solvent, the processes need temperatures 90 °C higher with respect to the mixture without solvent, and ZnO arises at 250 °C. [ABSTRACT FROM AUTHOR]

Herein, we report the structural, optical, thermal and electrical transport properties of a new multicomponent salt (TBTA 2− )·2(IM + )·(water) [TBTA–IM] of tetrabromoterepthalic acid (TBTA) with imidazole (IM). The crystal structure of TBTA–IM is determined by both the single crystal and powder X-ray diffraction techniques. The structural analysis has revealed that the supramolecular charge assisted O − ⋯H N + hydrogen bonding and Br⋯π interactions play the most vital role in formation of this multicomponent supramolecular assembly. The Hirshfeld surface analysis has been carried out to investigate supramolecular interactions and associated 2D fingerprint plots reveal the relative contribution of these interactions in the crystal structure quantitatively. According to theoretical analysis the HOMO–LUMO energy gap of the salt is 2.92 eV. The salt has been characterized by IR, UV–vis and photoluminescence spectroscopic studies. It shows direct optical transition with band gaps of 4.1 eV, which indicates that the salt is insulating in nature. The photoluminescence spectrum of the salt is significantly different from that of TBTA. Further, a comparative study on the antibacterial activity of the salt with respect to imidazole, Gatifloxacin and Ciprofloxacin has been performed. Moreover, the current–voltage ( I – V ) characteristic of ITO/TBTA–IM/Al sandwich structure exhibits good rectifying property and the electron tunneling process governs the electrical transport mechanism of the device. [ABSTRACT FROM AUTHOR]

The effect of the CO 2 saturation time of the aqueous suspension of the raw, primary low-surface ZnO on material properties has been investigated. The materials have been investigated by means of the following techniques: XRD, TG/DTG coupled with MS, N 2 physical sorption and SEM. The results reveal platelet-like hydrozincite as a product of saturation, which undergoes thermal decomposition to ZnO of the similar morphology. The modification of ZnO through the CO 2 saturation results in essential changes of the morphology. During the subsequent thermal decomposition porous structure is created with a simultaneous drastic increase of the specific surface area. All these changes lead to the conversion of “common” zinc oxide into active zinc oxide. [ABSTRACT FROM AUTHOR]

In this paper we report on crystal structure and oxygen storage properties of A-site cation ordered BaLnMn 2 O 5+δ (Ln: Pr, Nd, Sm, Gd, Dy, Er and Y) perovskite-type oxides. The materials show practically complete and reversible change between fully reduced BaLnMn 2 O 5 and oxidized BaLnMn 2 O 6 , which occurs at moderate temperatures (300–500 °C) during changes of the oxygen partial pressure (air, 5 vol.% H 2 in Ar). Based on the thermogravimetric measurements, reversible oxygen storage capacity, characteristic temperature of oxidation and reduction, as well as kinetics of these processes are given. Structural characterization was performed at room temperature for the reduced and oxidized materials by Rietveld analysis of the XRD data. These results are accompanied by in situ high temperature XRD measurements of the oxidation process, performed for BaNdMn 2 O 5 in air. [ABSTRACT FROM AUTHOR]

Porous carbon materials have been contributing to many areas of modern science and technology owing to their high specific surface area, large pore volume, and good electric and thermal conductivity, as well as mechanical and chemical stability. In this study, mesoporous carbon FDU-15 was modified with 3-mercaptopropyl-trimethoxysilane by ultrasonic irradiation. The X-ray diffraction (XRD) patterns show that mesoporous FDU-15 has a highly ordered hexagonal mesostructure and transmission electron microscopy (TEM) images verify the presence of large pores and a relatively ordered mesostructure for the functionalized materials. Different amount of modified FDU-15 (1, 2 and 3 wt. %) were used as reinforcing agent for the preparation of nylon-6/FDU nanocomposites. The obtained hybrid materials were characterized by Fourier transform-infrared spectroscopy, XRD, field emission-scanning electron microscopy, and TEM techniques. Thermogravimetric analysis data show that the onset of decomposition temperature of the nanocomposites was higher than that of pristine nylon-6, shifting toward higher temperatures as the amount of modified-FDU was increased. TEM images show well-ordered hexagonal arrays of mesopores and the average distances between neighboring pores is around 3-5 nm. [ABSTRACT FROM AUTHOR]

ABSTRACT In the preparation of polymer/montmorillonite (MMT) nanocomposites, the commonly used compatibilizers (cations of long carbon-chain alkyl ammonium salts) present the drawback of a poor thermal stability. During bulk processing of nanocomposites elevated temperatures are usually required and, if processing temperature is close to decomposition temperature of the surfactant, decomposition will occur altering the interface between filler and polymer. To solve this problem, organically modified MMTs with thermally stable imidazolium surfactants have been prepared. A series of nanocomposites were obtained by dispersing o-MMT in poly(methyl methacryate) (PMMA) matrix via an in situ free radical polymerization. The nanocomposites were characterized by X-ray diffraction, transmission electron microscopy, gel permeation chromatography, thermogravimetric analysis, dynamic mechanical analysis, and nanoindentation measurements. The results showed that nanocomposite thermal stability depended on both the kind of used surfactant and degree of exfoliation. Under the same values of molecular weight, the nanocomposites containing imidazolium cations showed a better thermal stability with respect to the nanocomposite obtained using a standard alkylammonium surfactant. Dynamic mechanical and Nanoindentation measurements showed an improvement of mechanical properties, such as modulus and hardness, with respect to pure PMMA. Solution blending treatments on these nanocomposites led to obtaining of further improvement of the thermal performance. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41393. [ABSTRACT FROM AUTHOR]

By combining two types of ligands, phenylpyridine and quinoline, a new type of organometallic IrQ(ppy)2 compound has been synthesized, which exhibits two phosphorescences: green and red. Using an appropriate catalyst, the final IrQ(ppy)2 compound has a good chemical yield up to 60% and becomes a stable dual emitter at room temperature. This compound is important because it exhibits stable red emission which is limited by the quantum yield due to the low energy band gap. As a result, an overlap between the ground state and the excited state occurs due to the vibrations that increase the nonradiative transitions, destroying the red emissions. Structural characteristics of the IrQ(ppy)2 powder reveal a triclinic structure confirmed by x-ray diffraction and scanning electron microscopy images. Thermal analysis of the final compound confirms a good stability against decomposition and structural changes up to 350 °C. X-ray photoelectron spectroscopy reveals Ir–O chemical bonds and several differences between the intermediate and final compounds, such as Ir–Cl bonds. Cathodoluminescence patterns show a phosphorescent triclinic structure with a higher efficiency for the red color. Backscattering electron images prove that there is a uniform distribution of iridium ions in the IrQ(ppy)2 nanocrystals. [ABSTRACT FROM PUBLISHER]

ABSTRACT Polyamide 6 (PA6) nanocomposites based on epoxy resin-modified montmorillonite (EP-MMT) were prepared by melt processing using a typical twin-screw extruder. X-ray diffraction combined with transmission electron microscopy was applied to elucidate the structure and morphology of PA6/EP-MMT nanocomposites, suggesting a nearly exfoliated structure in the nanocomposite with 2 wt % EP-MMT (PA6/2EP-MMT) and a partial exfoliated-partial intercalated structure in PA6/4 wt %EP-MMT nanocomposite (PA6/4EP-MMT). The thermogravimetric analysis under air atmosphere was conducted to characterize the thermal-oxidative degradation behavior of the material, and the result indicated that the presence of EP-MMT could inhibit the thermal-oxidative degradation of PA6 effectively. Accelerated heat aging in an air circulating oven at 150°C was applied to assess the thermal-oxidative stability of PA6 nanocomposites through investigation of reduced viscosity, tensile properties, and chemical structure at various time intervals. The results indicated that the incorporation of EP-MMT effectively enhanced the thermal-oxidative stability of PA6, resulting in the high retention of reduced viscosity and tensile strength, and the low ratio of terminal carboxyl group to amino group. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40825. [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, we aimed to physically and chemically modify wood flour (WF)/chitosan (CS) mixtures to reinforce the mechanical-, thermal-, and water-resistance properties of WF/CS/poly(vinyl chloride) (PVC) composites with a three-step modification process. This was a vacuum-pressure treatment of sodium montmorillonite, inner intercalation replacement of organically modified montmorillonite, and surface grafting of glycidyl methacrylate (GMA). The untreated and modified mixtures were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy-energy-dispersive spectroscopy, thermogravimetric analysis, and contact angle measurement. Meanwhile, the mechanical strengths and water absorption of WF/CS/PVC were estimated. The results indicate that the samples had a better performance after they were modified by montmorillonite (MMT) + GMA than when they were modified by only MMT. MMT and GMA showed a very synergistic enhancement to the mechanical-, thermal-, and water-resistance properties of the WF/CS/PVC composites. Specifically, the maximum flexural and tensile strengths were increased by 10.59 and 12.28%, respectively. The maximum water absorption rate was decreased by 61.99%, and the maximum degradation temperature was delayed to the higher value from 314.3 and 374.9°C in the untreated sample to 388.8 and 412.8°C. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40757. [ABSTRACT FROM AUTHOR]

ABSTRACT Porous materials have specific properties, such as high surface area, high permeability, lightweight, and low thermal conductivity. In foaming process of thermoplastics, high melt viscosity is indispensable. Neither poly(lactic acid) (PLA) nor poly(butylene succinate) (PBS) has sufficient melt viscosity. In this manuscript, Organophilic montmorillonite (OMMT) was employed to improve the foaming performance PLA/PBS blends. Mechanical tests were undertaken to compare the performance change of PLA/PBS foams before and after reinforcement of OMMT. The compression feature of PLA/PBS foams was discussed. X-ray diffraction (XRD) and scanning electron microscopes were performed to investigate the interaction between OMMT and PLA/PBS foams and the influence of OMMT on cell structure. The results indicated that OMMT can improve the effect of foaming markedly. With 3 wt % OMMT, The compressive strength, flexural strength, and impact strength raised up to 9.2 MPa, 14.0 MPa, and 31.2 kJ/m2, respectively, and the average size of cells changed from 475.6 to 261.4 µm. FT-IR, TGA, and XRD analysis suggested that CTAC has inserted into the Na-MMT platelets and OMMT platelets are more likely to be intercalated or completely separated in PLA/PBS matrix. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40773. [ABSTRACT FROM AUTHOR]

The effects of various drying techniques, such as air, oven, freeze, and spray drying, on the morphological, thermal, and structural behaviors of two different nanofibrillated cellulose (NFC) materials were investigated. Field emission scanning electron microscopy (FE-SEM) observations indicated an interlaced network formation of predominantly in-plane fibrillar orientation for air- and oven-dried samples, while freeze and spray drying resulted in the formation of coarse and fine powder fractions. Comparison of redispersed powders obtained by freeze and spray drying indicated that aggregation phenomena are significantly reduced in freeze-dried specimens. Rheological and sedimentation analysis revealed that the freeze-dried NFC powders are more stable than spray-dried NFC powders when redispersed in water. Aggressive dehydration processes, such as freezing or heating, significantly influence the thermal stability of the dried cellulose samples. On the contrary, the crystallinity properties of dried NFC materials are very similar regardless of the drying treatment. [ABSTRACT FROM AUTHOR]

Abstract: A space-maintaining ability of degradable guided bone regeneration (GBR) membranes is still a challenge due to weak mechanical strength despite their excellent concept. Here we incorporated functionalized-carbon nanotube (f-CNT) for this purpose. In particular, a hybrid composition of chitosan/silica (CS/Si) was used as the matrix of the GBR membrane. With increasing f-CNT content, hydrophilic nature increased while hydrolytic degradability was reduced. Among the membranes with various contents of f-CNT (up to 3 wt%), 2wt% f-CNT-doped CS/Si showed the highest mechanical properties, including tensile strength and elastic modulus as well as significantly improved bone bioactivity with respect to CS/Si free of f-CNT. In vivo animal study showed favorable tissue responses of the CNT-incorporated membrane. Taken all, the newly-developed CNT/CS/Si may find potential usefulness as a GBR membrane with excellent mechanical properties while exhibiting good bioactivity and tissue reaction. [Copyright &y& Elsevier]