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This study describes the applicability of lignocellulosic fiber dispersed in ethylene vinyl acetate (EVA) to adsorb Pb(II), Cr(III), and Cr(VI) ions in aqueous solutions. Water absorption studies revealed that metal-ion uptake does not only take place on the surface of the adsorbent but ions can also diffuse into the composite. The adsorption of the metal ions under different experimental conditions was studied. Solute concentration, pH, and contact time were used to assess the adsorption capacity and efficiency. The amount of metal adsorbed increased to 7 mg/g with an increase in solute concentration but compromising the efficiency. Adsorption equilibrium was reached after 3 h, when the maximum lead adsorption was above 80%. The optimum pH for the adsorption of Pb(II) and Cr(III) was 6.5, and pH 2.5 was used for the adsorption of Cr(VI). Competitive adsorption revealed the order of adsorption to be: Pb(II) > Cr(VI) > Cr(III). POLYM. ENG. SCI., 52:760–767, 2012. a 2011 Society of Plastics Engineers

Reaction of 5α-cholestan-6-one oxime (1), its 3β-acetoxy and 3β-chloro analogs, 2 and 3, respectiveley, with ClCH2CH2NH2⋅HCl in presence of MeONa afforded 6-[(2-aminoethoxy)imino]-5α-cholestane (4), 3β-acetoxy-6-[(2-aminoethoxy)imino]-5α-cholestane (5), and 6-[(2-aminoethoxy)imino]-3β-chloro-5α-cholestane (6), respectively. The structures of newly synthesized compounds have been established on the basis of physical, analytical, and spectral data. Theoretical calculations were assessed by using DFT at B3LYP/6-31G* level to describe the mechanism of the reaction. The stability and feasibility of all the generated structures studied in this report were supported by their respective fundamental frequencies and energy minima.

Reaction of tin dichloride and tin tetrachloride with cyclohexylamine-N-thiohydrazide (ChaThz) [L1] and 1,3-propanediamine-N-thiohydrazide (PdaThz) [L2] results in [Sn(ChaThz)2] (1), Sn(ChaThz)2Cl2] (2), [Sn(PdaThz)2] (3), and [Sn(PdaThz)2Cl2] (4), in which the thiohydrazide coordinates to tin through imine nitrogen and thioamide sulfur. The ratio metal : ligand was 1 : 2 for all complexes. The tin(IV) thiohydrazide complexes were characterized by elemental analysis, IR, UV-Vis, 1H-NMR, 119Sn NMR, and mass spectral studies. Using the disc diffusion method, the ligands and metal complexes were screened for in vitro antibacterial activities against four pathogenic bacteria, Escherichia coli, Staphylococcus aureus, P. aeruginosa, and Bacillus cereus and for antifungal activities against Aspergillus flavus, A. carbonarius, A. niger, and A. fumigatus. While the tin(IV) complexes exhibited moderate antifungal activities, their parent ligands showed much higher and long-lasting broad spectrum of bioactivity agai...

3β-Acetoxy-5α-cholestan-6-one semicarbazone 1 on reaction with hydrogen peroxide affords selectively 3β-acetoxy-5α-cholestan-6-spiro-1′,2′,4′-triazolidine-3′-one 2. The structural assignment of the product was confirmed by spectral data and elemental analysis. A free radical mechanism of the present reaction was described successfully by calculating theoretical models of 1, A, B and 2, using DFT with B3LYP/6-31G* basis set. It was found that the reaction undergoes through the formation of two radical intermediates and the only one isomer of the product in which –NH–CO– group is cis with respect C5α-H, was selectively obtained. Frontier molecular orbital, spin electronic density, electrostatic potential and atomic charges were discussed.

In an attempt to enhance the energy storage capacity and discharge voltage, a new cathode material based on ferrocene and LiF for lithium-ion batteries has been explored [Fe/LiF/C] nanocomposite ( 1 ) has been synthesized by pyrolysis of a ferrocene/LiF mixture at 700 °C using a rotating quartz tube setup in a furnace. The structure and morphology of the composite were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), Brunauer–Emmer–Teller (BET) analysis, Raman, and Mossbauer spectroscopy. The nanocomposite is composed of well-defined nanotubes which are interlinked by graphitic shell-type structures containing uniformly distribution of Fe, Fe–C, and LiF nanoparticles. The binder-free nanocomposite cathode showed enhanced electrochemical performance with the reversible specific capacity of 230 mAh g −1 (1.3–4.3 V) at 20.8 mA g −1 at room temperature. It exhibited a remarkable cyclic stability and good rate capability performances. The morphology of 1 was changed by ball milling, and the resulting nanocomposite 2 did not show any cyclic stability as a cathode. Thus, the cyclic stability and rate capability performances of 1 were attributed to its structure and morphology.

In this study, EVA/clay nanocomposites were prepared by two different methodologies i.e. melt blend technique and solution blend technique. Comparative analyzes of morphological and thermal properties of the nanocomposites fabricated by two different methods were done. The modified solution method was found to be an efficient method to obtain nanocomposite strips with uniform dispersion of the clay at organoclay loading of 8% and crystallinity by extrusion. The melt blending method produced nanocomposites with high porosity, intercalation, and thermal stability, whereas solution blending technique resulted in composites with more intercalated-exfoliated morphology, and less porosity and thermal stability.

Chitosan-N-2-methylhydroxypyridine-6-methylcorboxylate (Ch-PDC) and chitosan-N-2-methylhydroxypyridine-6-methylhydroxy thiocarbohydrazide (Ch-PDC-Th) were synthesized for the first time using chitosan as precursor. Chitosan, Ch-PDC, Ch-PDC-Th were used in the synthesis of gold nanoparticles (AuNP) in aqueous medium. Chitosan and Ch-PDC-Th possess reducing properties which enabled the 'green' synthesis of AuNPs. The stabilization of the AuNPs was as a result of the thiocarbide (SC) and amine (NH(2)) groups in the chitosan matrix. The modified chitosan, its derivatives and the resulting AuNPs were characterized by Fourier transform infrared (FTIR) spectroscopy, Ultraviolet-visible (UV-vis) spectroscopy, Raman scattering measurements, powder X-ray diffraction (PXRD) and thermo gravimetric analysis (TGA). Particle size, morphology, segregation and individuality of the AuNPs were examined by transmission electron microscope (TEM) and energy dispersion spectroscopy (EDS). An average AuNPs size of 20 nm was observed for chitosan and Ch-PDC-Th while Ch-PDC was 50 nm. In comparison, AuNPs resulting from Ch-PDC-Th precursor has the most enhanced Raman and fluorescent intensities and was stable for over 2 months.

In this study, ethylene vinyl acetate (EVA) was mixed with clinoptilolite (C), a natural zeolite, to prepare EVA-C nanocomposites. The films were characterized by SEM-EDS, XRD, and FT-IR, and heavy metal removal was studied using the batch technique. The effects of the initial pH value and concentration of solutions, contact time, and filler dosage on the adsorption capacity of the composites were investigated. To study the influence of pretreatment on the filler, clinoptilolite was activated using KCl, NaCl, and HCl. Adsorption results show that equilibrium was reached after 24 h, and that sorption reached its maximum at pH values between 5 and 7. The selectivity trend was observed to be Pb > Cu > Co, which was consistent for both single and mixed metal-ion solutions. Pretreatment significantly increased adsorption capacity of the composite, but was dependent on the conditioning reagent. Nanocomposites filled with HCl-activated particles demonstrated a high adsorption capacity of between 70 and 80% for all three metals, while KCl-activated particles were the least efficient with a maximum adsorption capacity of 69% for Pb(II), 54% for Cu(II) and 48% for Co(II). The adsorption data were then fitted to both Langmuir and Freundlich isotherms over the entire concentration range, and the Langmuir isotherm showed a better fit of the experimental sorption data than the Freundlich isotherm. The results obtained show that this simple methodology which can be up-scaled has great potential for the preparation of a wide variety of similar particle-filled adsorbent nanocomposites in other environmental remediation applications. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

Organoclay of the type Cloisite® 20A (C-20A) with two structurally different but semicrystalline polymer matrices was studied. Polycaprolactone (PCL), a linear, biodegradable polymer, and ethylene vinyl acetate (EVA), a branched copolymer, were chosen to prepare polymer clay nanocomposites via the melt-blending method. The results show that the structure of a polymer matrix plays a significant role towards compatibilization with the silicate layers of the clay. Scanning electron microscopy and X-ray diffraction analyses revealed an exfoliated-intercalated mixed morphology for the PCL matrix. However, for the EVA matrix, silicate layers agglomerated to form tactoids and resulted primarily in an intercalated morphology. Fourier transform infrared spectroscopy was used to determine the nature of the interactions between the polymer and the filler. The thermal properties were investigated using thermogravimetric analysis and indicated that, with an increase in clay loading, the thermal stability was reduced for both matrices. Tensile tests suggested that Young’s modulus improved for the EVA matrix with an increase in clay dosage whereas for PCL the modulus was found to be highest for 8% clay loading.

The fabrication of carbon nanotube/polyvinyl chloride (PVC) composites and a study of their thermal and mechanical properties are reported. Phosphorylated multiwalled carbon nanotube (p-MWCNT) and pristine MWCNT were used. The MWCNT were embedded in the polymer matrix through melt mixing. The phosphorylation of the MWCNT and their dispersion in the PVC matrix were characterized by scanning and transmission electron microscopy and Raman spectroscopy. Thermal analysis by thermal gravimetric analysis and differential scanning calorimetry, showed an increase in glass transition temperature and melting temperature for the composites with respect to pure PVC. The modulus of the MWCNT/PVC composites increased while there was a reduction in their tensile strength, indicating a decrease in polymer toughness.

Transition metal complexes of the type [M(L)(2)] and those containing monodentate phosphines of the type [M(L)(2)(PPh(3))] {M=Ni, Co, Cu and Zn; L=cyclohexylamine-N-dithiocarbamate; PPh(3)=triphenylphosphine} have been synthesized. The complexes were characterized using IR, UV-vis, NMR spectroscopy, and thermal analysis (TGA). The (1)H NMR, (13)C NMR and (31)P NMR showed the expected signals for the dithiocarbamate and triphenylphosphine moieties. The spectral studies in all compounds revealed that the coordination of metals occurs via the sulphur atom of the dithiocarbamate ligand in a bidentate fashion. Thermal behavior of the complexes showed that the complexes were more stable than their parent ligands. The ligand moiety is lost in the first step and the rest of the organic moiety decomposes in the subsequent steps. Furthermore, the ligand and their metal complexes were screened in vitro for their antibacterial activity against Escherichia coli, Staphylococcus aureus, Salmonella typhi, Enterococcus faecalis, Pseudomonas aeruginosa and Bacillus cereus and antifungal activities against Aspergillus flavus, Aspergillus carbonarius, Aspergillus niger and Aspergillus fumigatus. The metal complexes exhibited higher antimicrobial activity than the parent ligands. Generally, the zinc complexes were effective against the growth of bacteria with Zn(L)(2) displaying broad spectrum bacteriocidal activity at concentrations of 50microg/mL; and Ni(L)(2) was more effective against the growth of fungi at concentrations of 100-400microg/mL under laboratory conditions.

In this study, we have synthesized chitosan-grafted-styrene (Ch-g-sty) without any radical initiator or catalyst using microwave (MW) irradiation. Ch-g-sty was synthesized with 187% grafting using 80 % MW power in 40 second at (styrene) 0.13 M, (Chitosan) 0.1 g/25 mL. On the other hand, under similar condition of concentration of styrene and chitosan, 148% grafting was observed with potassium persulphate (K2S2O8)/ascorbic acid as redox initiator and atmospheric oxygen as co-catalyst in 1 h using conventional method at 35 o C. Microwave synthesized Ch-g-sty copolymer was characterized by Fourier transformInfrared (FTIR) spectroscopy, thermo gravimetric analysis (TGA), X-ray diffraction (XRD) measurement and scanning electron microscopy (SEM). Maximum grafting was optimized by varying the microwave power, exposure time and styrene/chitosan concentration. Ch-g-sty copolymer was found to be more efficient for Cr(VI) removal as compare to conventionally and parent chitosan in aqueous solution. Sorption of Cr(VI) was depending upon pH and concentration, with pH=3 being the optimum value. The equilibrium data followed the Langmuir isotherm model with maximum capacities of 526.3 mg/g, 312.5 mg/g and 166.7 mg/g for Ch-g-sty copolymer, conventional (thermostatic water bath) method and parent chitosan respectively. Copyright © 2010 VBRI press.

The effect of nano-particles of TiO2 on the mechanical and thermal properties of sugarcane bagasse (SCB)–ethylene co-vinyl acetate (EVA) composite was investigated. Composite materials were prepared using a melt-mix intercalation method on a rheomex mixer coupled with a single screw extruder. differential scanning calorimeter (DSC), thermogravimetric (TG) analyser and an Instron, were used to probe the thermal and mechanical properties of the samples. Composites with TiO2 were compared with those without TiO2 but with the same content of sugarcane bagasse (SCB). After the addition of TiO2, the tensile strength increased by 10%, from 11.26 MPa for neat EVA, which correlated with the enthalpy of fusion, however, the tensile strength decreased by 18% at higher SCB loading. Elongation at break decreased from 463 to 0% as the filler (SCB) was increased which was inversely proportional to the modulus. The composite showed an improved thermal stability with the addition of TiO2.

A 20-mer single-stranded oligodeoxyribonucleotide (ssODNs) was covalently probed onto the nanocomposite electrode, made up of an indium-tin oxide (ITO) glass surface coated with chitosan (CHIT), which is bonded with carboxyl functionalized thiol capped gold nanoparticles (gold-mercaptopropionic acid, Au-MPA NPs). The prepared CHIT/Au-MPA/ITO and the ssODNs/CHIT/Au-MPA/ITO electrodes were characterized with FTIR spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and cyclic voltammetry (CV). TEM micrograph of the composite electrode showed that Au-MPA NPs had the diameter ranging from 4 to 16 nm. The ssODNs/CHIT/Au-MPA/ITO electrode showed a linear increase in the amperometric current with an increasing concentration of the single-stranded target complementary ODNs (cODNs) within the range of 0.03–325 fM. The ssODNs/CHIT/Au-MPA/ITO electrode exhibited a sensitivity of 0.572 μA/fM with a response time of 12 s. The ssODNs/CHIT/Au-MPA/ITO electrode had a shelf life of ∼182 days, when stored at 4 °C.

Attempts have been made to look for the exact solutions of certain types of nonlinear diffusion–reaction equations which involve not only the quadratic and quartic nonlinearities but also a time-dependent nonlinear convective flux term. In particular, the solitary wave solutions are found. Such equations arise in a variety of contexts in physical and biological problems.

In this study, we have synthesized chitosan-grafted-styrene (Ch-g-sty) without any radical initiator or catalyst using microwave (MW) irradiation. Ch-g-sty was synthesized with 187% grafting using 80 % MW power in 40 second at (styrene) 0.13 M, (Chitosan) 0.1 g/25 mL. On the other hand, under similar condition of concentration of styrene and chitosan, 148% grafting was observed with potassium persulphate (K2S2O8)/ascorbic acid as redox initiator and atmospheric oxygen as co-catalyst in 1 h using conventional method at 35 o C. Microwave synthesized Ch-g-sty copolymer was characterized by Fourier transformInfrared (FTIR) spectroscopy, thermo gravimetric analysis (TGA), X-ray diffraction (XRD) measurement and scanning electron microscopy (SEM). Maximum grafting was optimized by varying the microwave power, exposure time and styrene/chitosan concentration. Ch-g-sty copolymer was found to be more efficient for Cr(VI) removal as compare to conventionally and parent chitosan in aqueous solution. Sorption of Cr(VI) was depending upon pH and concentration, with pH=3 being the optimum value. The equilibrium data followed the Langmuir isotherm model with maximum capacities of 526.3 mg/g, 312.5 mg/g and 166.7 mg/g for Ch-g-sty copolymer, conventional (thermostatic water bath) method and parent chitosan respectively. Copyright © 2010 VBRI press.

We report here the formation of silicon carbide (SiC) nanowires from inorganic–organic hybrid of sol–gel-derived silica and the commercially available lignin that is naturally abundant amorphous biopolymer. This organic–inorganic hybrid material in the absence of catalyst was carbothermally reduced for a period of 1ha t 14001C in inert atmosphere followed by oxidization. The nanostructures were characterized by scanning electron microscopy and high resolution scanning electron microscopy, which show the continuous formation of b-SiC nanowires in the range of 50–200 nm diameter and length of few micrometers. Transmission electron microscopy revealed Y-shaped structures (branched) of the nanowires grown in the direction of parallel to the [100] plane having two heads and one leg. The nanowires were formed with joints that were formed at regular intervals as circular rings. The deposition of silica layer on the outer surface of the nanowires was also observed. According to the X-ray diffraction pattern, peaks at 2h 5 35.91 and 59.81 indicate the formation of b-SiC and a sharp peak at 2h 5 22.11 suggests the presence of unreacted crystalline silica (crystoballite). The Raman shifts for b-SiC appeared as small peaks at 795.6 and 983.1 cm � 1 , respectively. The characteristic vibration of SiC at 795 cm � 1 in Fourier transform infrared spectroscopy was also observed.

Phosphor-based polymer composites were prepared using a melt mixing and extrusion method. Mor- phology, luminescent properties, and Hamburg wheel test (HWT) of synthesized hybrid material were studied using various polymer matrices. The intensities of the luminescence of the strontium aluminates phosphors (SrAl2O4 : Eu,Dy and Sr4Al14O25 : Eu,Dy) were substantially changed when incor- porated into structurally and chemically different organic matrices. HWTs were performed to evaluate the durability of the polymers against simulated wheel loads and the effect of these wheel loads on the luminosity of the polymers. The decay slopes of various polymer-phosphor composites sug- gests that the simulated wheel load of the Hamburg test did not have a profound effect on the luminosity as such but the duration of luminescence was found to be shorter for the polymer-phosphor hybrid after the Hamburg test. V C 2009

A nanofibrous polyaniline (PANI) thin film was fabricated using plasma-induced polymerization method and explored its application in the fabrication of NO2 gas sensor. The effects of substrate position, pressure, and the number of plasma pulses on the PANI film growth rate were monitored and an optimum condition for the PANI thin film preparation was established. The resulting PANI film was characterized with UV–visible spectrophotometer, FTIR, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The PANI thin film possessed nanofibers with a diameter ranging from 15 to 20 nm. The NO2 gas sensing behavior was studied by measuring the change in electrical conductivity of PANI film with respect to NO2 gas concentration and exposure time. The optimized sensor exhibited a sensitivity factor of 206 with a response time of 23 sec. The NO2 gas sensor using nanofibrous PANI thin film as sensing probe showed a linear current response to the NO2 gas concentration in the range of 10–100 ppm. Copyright © 2009 John Wiley & Sons, Ltd.

Nickel(II) complexes of type [Ni(L)2Cl2] and [Ni(L)2(OCOCH3)2], where L = (cyclohexyl-N-thio)-1,2-ethylenediamine (L1) and (cyclohexyl-N-thio)-1,3-propanediamine (L2) has been synthesized and characterized by elemental analysis, FT-IR, mass, UV-Vis, and 1H NMR spectroscopic studies. The thiodiamines coordinate as a bidentate N-S ligand. The ratio of the metal: ligand was 1: 2 for all the complexes. The binding sites are the azomethine nitrogen and thioamide sulfur. The complexes are found to be soluble in acetone, dimethylformamide, and dimethylsulfoxide. All the complexes were found amorphous in nature. Molar conductance values in DMSO indicate the nonelectrolyte nature of the complexes. In vitro antifungal and in vitro antibacterial studies were performed against fungal and bacterial strains, Aspergillus fumigatus, Aspergillus flavus, and Aspergillus niger, and Staphylococcus epidermidis, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa, respectively. Preliminary antimicrobial screening shows the good results against both the fungal and the bacterial strains, which can lead through the investigation of better drug.

A comparison between activated charcoal and heat-treated coal for decolourization of pulp and paper mill waste water was studied. The heat-treated coal was prepared in an inert atmosphere at 800°C. The adsorption dynamics that include batch contact–time study, kinetics along with adsorption isotherms were carried out. The study shows that heat-treated coal is a suitable adsorbent and can be used for the decolourization of pulp and paper mill effluent streams. The maximum removal was achieved at the initial stages of contact, and the overall adsorption was a slow process. However, the equilibrium concentration in the case of both the adsorbents reaches at almost same time. The linear plot of the Lagergren model shows its applicability and first-order kinetics.

Common components are used extensively for reasons including product postponement and expediting new product development. We consider a two-stage assemble-to-order system with two products having uniformly distributed demand, one common component, and product-specific components. We develop optimization models in which the cost-minimizing inventory of the components must be determined and allocated to products in order to meet product-specific service level constraints. We compare two different commonality models based on whether or not the products are prioritized. A distinctive feature of our study is the use of product-specific service levels. We compare our results with models using aggregate service levels.

Nickel(II) complexes of type [Ni(L)(2)Cl(2)] and [Ni(L)(2)(OCOCH(3))(2)], where L=N,N-diphenyl-N-thiohydrazide (L(1)) and (N,N-diphenyl-N-thio)-1,3-propanediamine (L(2)), have been synthesized. The thiodiamines coordinate as a bidentate N-S ligand. The synthesized nickel(II) complexes of the thiodiamines were characterized by elemental analysis, IR, mass, electronic and (1)H NMR spectroscopic and TG/DTA studies. Various kinetic and thermodynamic parameters like order of reaction (n), activation energy (E(a)), apparent activation entropy (S(#)) and heat of reaction (DeltaH) have also been carried out for one complex. These complexes were also screened for in vitro antifungal and in vitro antibacterial activities and significant activity have been found.

The influence of nano-silica, synthesized and mixed with low-density polyethylene (LDPE) through a sol–gel process, on the thermal and mechanical properties of LDPE and LDPE/wood flour (WF) composites, prepared in the absence and presence of dicumyl peroxide, was investigated. Scanning electron microscopic (SEM) analyses show a uniform dispersion of silica nano-particles of size 10–50 nm in the matrix, and Fourier-transform infrared (FTIR) spectroscopic results indicated interaction between the nano-silica and the LDPE matrix, which seems to improve for samples prepared in the presence of dicumyl peroxide (DCP). WF and nano-silica, as well as the presence of DCP during sample preparation, substantially improve the thermal stability of the LDPE matrix. The tensile strength of the samples decreased with increasing wood flour content, while the tensile modulus substantially increased. The presence of nano-silica gave rise to lower values for both tensile strength and tensile modulus, while higher tensile strength (and an increase in tensile strength with WF content) is observed for samples prepared in the presence of DCP. The tensile modulus increases with increasing WF content, but is not substantially influenced by the presence of nano-silica or by sample preparation in the presence of DCP. The DMA results were in line with the tensile results.

Some new platinum (IV) and palladium (II) thiodiamine complexes of type [Pt(L)2Cl2] and [Pd(L)Cl2], [where, L=(cyclohexyl-N-thio)-1,2-ethylenediamine (L(1)) and (cyclohexyl-N-thio)-1,3-propanediamine (L(2))] have been synthesized. The thiodiamines coordinate as a bidentate N-S ligand. The synthesized platinum (IV) and palladium (II) complexes of the thiodiamines were characterized by elemental analysis, IR, mass, electronic and (1)H NMR spectroscopic studies. These complexes were also screened for cytotoxicity, in vitro antifungal and in vitro antibacterial activities. Thermodynamic parameters such as activation energy (Ea), apparent activation entropy (S(#)) and enthalpy change (DeltaH) for the dehydration and decomposition reactions of one complex has also been evaluated.

Platinum(IV) and palladium(II) complexes [Pt(L)2Cl2] and [Pd(L)Cl2], [where, L = 1,1-diphenyl-2-thiosemicarbazide (L1) and (1,1-diphenyl-2-thio)-1,3-propanediamine (L2) have been synthesized. The thiosemicarbazides and thiodiamines exist as the thione-thiol tautomer and coordinate as a bidentate N-S ligand. The ligands are monobasic bidentate. The complexes have been characterized by elemental analysis, IR, mass, electronic and 1H NMR spectroscopic studies. In vitro antibacterial studies have also been carried out for some complexes.

Palladium(II) complexes of type [Pd(L)Cl2] [where, L = benzaldehyde-1,1-diphenyl-2-thiohydrazone (L1), salicylaldehyde-1,1-diphenyl-2-thiohydrazone (L2), acetaphenone-1,1-diphenyl-2-thiohydrazone (L3) and cyclohexanone-1,1-diphenyl-2-thiohydrazone (L4)] have been synthesized. The thiohydrazones can exist as thione-thiol tautomers and coordinate as a bidentate N–S ligand. The ligands are found to be monobasic bidentate. The complexes have been characterized by elemental analysis, IR, mass, electronic, 1H NMR spectroscopic studies. In vitro antifungal studies against fungi Aspergillus fumigatus, Aspergillus flavus and Aspergillus niger for some complexes have also been carried out.

Ferromagnetic nanoparticles in a carbon matrix were synthesized by thermal decomposition of organic precursor maleic anhydride using different molecular weight percentages of organometallic precursor ferrocene at temperature of 900 and 980 ∘ C . The effect of preparation treatment on the phase composition, microstructure and magnetic properties were investigated using X-ray diffraction, transmission electron microscopy, Mossbauer spectroscopy and superconducting quantum interference device (SQUID) magnetometer.

A change of the DC electrical conductivity of a nanoporous Au 0.75 Fe 0.25 alloy was observed when surface charge was induced on the nanomaterial by making it a working electrode in an electrochemical cell. Simultaneous voltammetry and conductivity measurements over several voltage cycles in the range −0.4 to +0.7 V showed a reversible change in conductivity of 1.3%. The variation of conductivity with induced charge is interpreted in terms of the Sommerfeld model for metallic conduction.

A new class of renewable, biocompatible and biodegradable materials from agricultural feedstock is fast emerging as an upcoming field of interest. The biopolymer lignin-based thermoplastics are fabricated through polymer blending and chemical modification that possess variety of applications. The existences of miscible polymer blends of lignin are rare. FTIR values and thermal analysis of our study revealed the formation of miscible blends of lignin with polyvinyl chloride (PVC). Optical measurements of these blends suggest increased surface reflectance with the increase in the amount of lignin. Film properties of the blends like scratch hardness, bend strength and impact values suggest the rigidity due to the presence of phenolic component and reduced flexibility of the polyblends.

Palladium(II) complexes of type [Pd(L)Cl2] [where L=2-aminopyridine-N-thiohydrazide (L1), (2-aminopyridine-N-thio)-1,3-propanediamine (L2), benzaldehyde 2-aminopyridine-N-thiohydrazone (L3) and salicylaldehyde-2-aminopyridine-N-thiohydrazone (L4)] have been synthesized. The thiohydrazide, thiodiamine and thiohydrazones can exist as thione-thiol tautomer and coordinate as a bidentate N-S ligand. The ligands found to act in bidentate fashion.

Organic waste material in water is accumulated from domestic and industrial discharge. The nature and type of organic contaminants in wastewater differ based on the industrial products and domestic usage. Some of the organic pollutants occur from soap and detergents, petroleum products, dye and textile industries, drugs and pharmaceuticals, herbicide and pesticide and many more. There are numerous technologies available for the treatment of organics that may include the physical, chemical, photocatalytic and microbial processes. The hydrogels offers eco-friendly substrates that have been investigated for decontamination of organics. There are varieties of hydrogels available for different application in pristine forms as well as synthetic forms. Among these, biopolymers that have been categorized as hydrogels and were used for treating organic pollutants have been discussed in this chapter.

Hydrogels are special types of polymers that have enormous capacity to absorb large volumes of water. Hydrogels are natural as well as man-made. To suit to a type of an application, hydrogel can be modified to tailor made properties that can be exploited for natural, applied, and medical sciences. This chapter deals with the recent research done in the area of hydrogels, modified hydrogels, hydrogel composites, and nanocomposites. General trends of the thrust areas where hydrogels have prime role of importance were biomedical and health care. However, the other areas such as environmental aspects for the utility of hydrogels have also been an area of interest among researchers across the globe.

Platinum (IV) complexes of type [Pt(L) 2 Cl 2 ] [where, L=benzaldehyde- N , N -diphenyl- N -thiohydrazone (L 1 ), salicylaldehyde- N , N -diphenyl- N -thiohydrazone (L 2 ), acetaphenone- N , N -diphenyl- N -thiohydrazone (L 3 ) and cyclohexanone- N , N -diphenyl- N -thiohydrazone (L 4 )] have been synthesized. The thiohydrazones can exist as thione–thiol tautomer and coordinates as a bidentate N–S ligand. The ligands found to act in monobasic bidentate fashion. Analytical data reveals that metal to ligand stoichiometry is 1:2. The complexes have been characterized by elemental analysis, IR, mass, electronic, 1 H NMR spectroscopic studies, and TG/DTA study. Various kinetic and thermodynamic parameters like order of reaction ( n ), activation energy ( E a ), apparent activation entropy ( S # ) and heat of reaction (Δ H ) have also been carried out for one complex. Cytotoxic study has also been carried out for one complex.

Platinum (IV) complexes [Pt (L)2Cl2] [where, L= benzyl-N-thiohydrazide (L1), (benzyl-N-thio)-1,3-propanediamine (L2), benzaldehyde-benzyl-N-thiohydrazone (L3) and salicylaldehyde-benzyl-N-thiohydrazone (L4)] have been synthesized. The thiohydrazide, thiodiamine and thiohydrazones can exist as thione-thiol tautomer and coordinate as a bidentate N-S ligand. The ligands were found to act in monobasic bidentate fashion. Analytical data reveal that metal to ligand stoichiometry is 1:2. The complexes have been characterized by elemental analysis, IR, mass, electronic and 1H NMR spectroscopic studies. In vitro antibacterial and cytotoxic studies have been carried out for some complexes. Various kinetic and thermodynamic parameters like order of reaction (n), activation energy (Ea), apparent activation entropy (S#) and heat of reaction (DeltaH) have also been carried out for some complexes.

A few Pt(IV) complexes of the type [Pt(L) 2 Cl 2 ] [where L = morpholine dithiocarbamate (L 1 ), aniline dithiocarbamate (L 2 ), N -(methyl, cyclohexyl) dithiocarbamate (L 3 ) and N -(ethyl, cyclohexyl) dithiocarbamate (L 4 )] were synthesized. The complexes have been characterized by elemental analysis, molar conductance, IR, electronic, 1 H and 13 C NMR spectroscopic studies. The ligands found to act in monobasic bidentate fashion. Cyclicvoltammetric studies, antibacterial and in vitro antitumour studies were also carried out.

Traditional inventory models assume that a buyer places one order with a supplier in each order cycle. A large number of researchers have studied the benefits of dual sourcing such that an order quantity is split and placed simultaneously with two suppliers. We show that many of the benefits of dual sourcing are due to order splitting rather than using two suppliers. We investigate order splitting with one supplier such that the first part of the order is sent out immediately but the second part of the order is released later (scheduled-release). Through extensive computational results, we show that in many situations where dual sourcing or the use of a cheaper supplier would be cost effective, single sourcing with order splitting using scheduled-release orders is better. The paper provides a quantitative rationale to continue with one supplier. We also summarize the qualitative reasons to prefer single sourcing or multiple sourcing.

Starting with Cu0.65Zn0.35 with an e/a ratio of 1.35 we studied the phase formation in nanophase (Cu0.65Zn0.35)1−xFex alloys in the concentration range 0.1 ≤x ≤0.7 to see the effect of altering the electron concentration. The evolution of bcc phase from the fcc phase as a function of Fe concentration was investigated by Mossbauer spectroscopy and X-ray diffraction. The grain size, lattice parameters, and average hyperfine magnetic field distributions were estimated for the nanophase alloys. The fcc phase was observed to persist up to 40 atomic per cent Fe substitutions, a mixed (fcc + bcc) phase region up to 70 atomic per cent Fe and bcc phase beyond 70 atomic per cent Fe. The magnetic state of the alloys changed from nonmagnetic forx ≤0.3 to magnetically ordered state at room temperature forx ≤0.33, which lies in the fcc phase region. The fcc phase alloys of Fe with non-magnetic metals have very low magnetic transition temperatures. However, in this system the room temperature state is unusually magnetic

Some new organotin(IV) complexes with salicylaldehyde aniline-N-thiohydrazone (L1) and cinamaldehyde aniline-N-thiohydrazone (L2) of the type (p-ClC6H4)3Sn[L] Cl and (p-ClC6H4)2Sn[L]Cl2 have been synthesized (where L = L1 and L2). The complexes and ligands were characterized by elemental analysis and spectral (UV-vis, IR and 1H NMR) studies. In all the complexes, ligands act as bidentate, coordination through sulphur and azomethane nitrogen. Complexes are 1:1 metal ligands complexes. Antifungal studies of some complexes against Rhizoctonia bataticola fungal strain have been carried out.

A new copper Nasicon of composition Cu0.5TaFeP3O12 has been prepared and reduced under hydrogen flow at 500 and 675 °C, separately. The unreduced and reduced products are characterized by IR spectra and powder X-ray diffraction. The copper Nasicon and the products obtained by its reduction crystallize in the rhombohedral lattice with space group R 3 ¯ c . The ESR and Mossbauer spectral results suggest only partial reduction of both Cu2+ and Fe3+ to Cu+ and Fe2+, respectively, with simultaneous hydrogen insertion to balance the charge. A reaction in conformity with the obtained results is proposed.

In this work, silicon carbide (SiC) nanoparticles were used to reinforce polycaprolactone (PCL). The nanocomposites were prepared by melt-mixing followed by mould extrusion. The effect of increased SiC loading on the thermal, mechanical, and dynamic mechanical properties was investigated using differential scanning calorimetry, tensile testing, and dynamic mechanical analysis (DMA), respectively. The morphology and chemical interactions were carried out by scanning electron microscopy and Fourier transform infrared spectroscopy (FTIR), respectively. The SiC nanoparticles were fairly well dispersed in the PCL matrix. FTIR indicated that there was no chemical interaction between PCL and SiC. The presence of SiC nanoparticles influenced the crystallization behavior of PCL, whereas there was no significant influence on thermal degradation behavior of PCL. Generally, the mechanical properties of the nanocomposite increased with an increase in nanoparticle content. The DMA results showed that the presence of SiC improved the storage modulus of PCL especially at higher SiC loading. Thermogravimetric analysis showed a very small influence of SiC on the thermal stability of PCL. Moreover, the glass transition temperature (Tg) of the nanocomposites shifted to lower temperatures compared to that of neat PCL. The crystal structure was not significantly influenced by the presence of SiC. The biodegradation process of PCL in soil environment delayed in the presence of SiC. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42145.

OBJECTIVES: To study the demographic characteristics, risk factors, long term mortality and morbidity among patients admitted with cerebrovascular accident in a tertiary care hospital in South India. METHODS: All patients diagnosed with cerebrovascular accident, who met the inclusion criteria were enrolled into the study which was conducted between December 2011 and June 2013. Baseline demographic data, risk factors and details of the stroke were recorded. The severity of stroke in all patients was scored with the Modified Rankin score (MRS) and National Institute of Health Stroke Scale (NIHSS) at admission. MRS, details of incontinence and dysphagia were obtained at 1 month, 6 months and 1 year through telephonic communication. RESULTS: Of the 439 patients enrolled into the study, 63% were males. 90% of the patients had accessed a medical care centre within 6 hours of onset of stroke, however only 45% had accessed a medical care centre offering neuroimaging and thrombolysis facilities.93% of patients had positive findings on imaging, 74% being ischemic in etiology. Hypertension was the most common risk factor (71%). 15% of these patients were newly detected to have hypertension and 25 % of the above were normotensive at discharge from hospital. Mortality in the hospital was 11%, the most common cause being severity of the stroke itself (in the first one week) followed by aspiration pneumonia (between 1st to 4th week). At follow up, 80% of the patients could be contacted and a majority of them (95%) responded positively to the telephonic mode of communication. Mortality at the end of 1 month, 6 months and 12 months was 25%, 31.7% and 33.7% respectively. Though nearly 50% of the patients had dysphagia and incontinence at admission, during the follow up there was a trend towards improvement of both. High MRS and NIH were good predictors of mortality. NIH correlated better with mortality than MRS. CONCLUSIONS: In a developing country like India, timely access to a competent health care facility still remains a challenge. Measures to prevent aspiration pneumonia will help in reducing mortality while in the hospital. NIHS was better than MRS in predicting mortality. Telephonic communication is a good method for follow up in resource limited settings.

Titania nanoparticles were successfully supported on carbon-covered alumina (CCA) supports via the impregnation method to form carbon-covered alumna titania (CCA/TiO2). The CCA supports were synthesised through an equilibrium adsorption of toluene 2,4-diisocyante where the N=C=O irreversibly adsorbs on the alumina and pyrolysis at 700°C affords CCA supports. These CCA/TiO2nanocatalysts were tested for their photocatalytic activity both under UV and visible light using Rhodamine B as a model pollutant. The reaction rate constant of the CCA/TiO2was found to be higher than that of unsupported titania and the reaction kinetics were found to follow an apparent first-order rate law. The CCA/TiO2nanocatalysts had a much larger surface area than the unsupported titania and they exhibited overall higher photodegradation efficiency under both UV and visible light than unsupported TiO2.

This research focuses on improving the photocatalytic efficiency of TiO2 during the photo-mineralisation of brilliant black (BN) bis-azo dye pollutant in aqueous solution. This was achieved by improving the visible light activity of TiO2 photocatalyst semiconductor through co-doping of fluorine (F) and trivalent samarium ions (Sm3+) into a TiO2 matrix using a modified sol-gel synthesis method. Structural, morphological, and textural properties were evaluated using ultra-violet /visible spectroscopy (UV-visible), Raman spectroscopy, scanning electron microscopy coupled to energy dispersive X-ray spectroscopy (SEM/EDX) and X-ray diffraction spectroscopy (XRD). Photocatalytic and degradation efficiencies were assessed by decolourisation of BN dye in aqueous solution. Complete degradation of BN was attained after an irradiation time of 3 h using F, Sm3+-TiO2 (0.6% Sm3+) compared to 73.4% achieved using pristine TiO2. Pseudo first order kinetics rate constants (Ka) were 2.73×10-2 and 6.6×10-3 min-1 for Sm3+-TiO2 (0.6%Sm3+) and pristine TiO2, respectively, which translates to a remarkably high enhancement factor of 4. The results obtained established that doping of TiO2 by F and Sm3+ enhances the photocatalytic performance of TiO2 during solar light radiation which enables the utilisation of freely available and clean solar energy.

Silicon carbide (SiC) nanorods were prepared by the pyrolysis of a hybrid of organic moiety (1,3-propanediamine) and methyltriethoxysilane (MTEOS). The organic–inorganic hybrid was developed using a sol–gel process and blending it with the organic moiety. The nanostructures were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) which revealed the continuous formation of β-SiC nanorods having a 30–100 nm diameter and a length of a few micrometers. The unreacted silica agglomerated to form lumps with the release of excess carbon during oxidation. Electron diffraction patterns from the nanowires revealed them to have the cubic β-SiC structure. This was in agreement with XRD data. There were found to be many periodically twinned or stacking faulted regions observed along the length of the nanowires. While this yielded a zig-zag pattern to the outside of the core and changes to the local internal diameter of the nanowires, there was no correspondence to the changes to the diameter of the outer sheaf. The Raman shifts for β-SiC appeared as small peaks at 795.6 and 983.1 cm −1 respectively. The characteristic vibration of SiC at 795 cm −1 in Fourier Transform Infrared Spectroscopy (FTIR) was also observed.