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This paper reports the enhancements for the effects of specific fluxes such as Tungsten Carbide and Chromium Oxide on the weldment properties such as micro hardness, weld bead geometry and tensile strength obtained with Gas Tungsten Arc Welding Process (GTAW) applied to 6 mm thick Chromium Manganese stainless steel plates. The significant expense of Nickel has made Chromium Manganese stainless steel as an option for conventional 300 arrangement stainless steel. The two fluxes tungsten carbide and chromium oxide were utilized in powdered structure. The tensile test, micro hardness test and corrosion resistance test was conducted to reveal the effect of fluxes on the weldment properties. Results of tensile shows that considerable enhancement in tensile strength and elongation of about 20% increase in case of Chromium Oxide coated samples and 10% increase in case of Tungsten Carbide samples when compared to uncoated specimen. In case of microhardness, 10% increase is exhibited for coated samples compared with uncoated samples. The corrosion rate of coated samples found to be highly resistant for coated samples, which sums to be 300% more than that of uncoated samples. The effect of corrosion rate on the specimens was seen by conducting SEM analysis after the corrosion test. The SEM analysis uncovered that the coating covers the limits encompassing the inclusions and encloses dendrites which reduce the pitting corrosion of the parent metal.

This work focuses on the optimization of process parameters for friction stir processed (FSP) AA 6061 for superior mechanical properties. The distinctive work is to integrate the Taguchi Method with the Grey Relational Experimental Analysis Technique (GREAT) for a hybrid portfolio. Eight experimental investigations were carried out with varying process parameters of two levels of tool speed (25 and 28 mm/s), processing speed (1000 and 1500 rpm) and pin profiles (cylinder and square) with reinforcements such as Silicon carbide (SiC), Titanium Carbide (TiC), Titanium DiBromide (TiB2) and Zirconium DiBromide (ZrB2) to uncover the influence that it holds to the process. Surface composites quality of all the samples was evaluated for tensile strength. After a single pass of FSP. TiC reinforcement showed a promising optimized welding quality at 1500 rpm, 25 mm/s with a square pin profile by GREAT. when TiC reinforcement was used along with the rotational speed of 1500 RPM, the processing speed of 25 mm/s with a square pin profile as a process parameter and significant improvement of 37.85% and 46.6% for tensile strength and yield strength respectively due to the grain refinement of added reinforcement particle dispersoids, processed AA6061 composites showed significant improvement in terms of material property.

Welding quality can be accomplished by meeting quality prerequisites, for example, bead geometry by detecting either directly or indirectly the different procedure parameters engaged with the procedure. Lacking weld bead measurements may add to the disappointment of a welded structure. This paper presents an improvement of a scientific model for foreseeing bead width for gas tungsten arc welding of 202-grade stainless steel plates. This model depends on the connection between procedure parameters and bead width and can be utilized to foresee the impact of procedure parameters on bead width. To assemble the required information for demonstrating, real tests were done dependent on a central composite rotatable plan with 31 test runs. The procedure factors considered here incorporate welding current (I), welding speed (V), gas flow rate (Q) and welding gun angle (θ). The sufficiency of the model was tried utilizing ANOVA procedure. The outcomes demonstrate that the proposed model can foresee bead width with sensible precision. Primary and cooperation impacts of the control factors are exhibited in a graphical structure that helps in choosing rapidly the procedure parameters to accomplish the ideal outcomes.

Toxicoproteomic analysis of steel industry ambient particulate matter (PM) that contain high concentrations of PAHs and metals was done by treating human lung cancer cell-line, A549 and the cell lysates were analysed using quantitative label-free nano LC-MS/MS. A total of 18,562 peptides representing 1576 proteins were identified and quantified, with 196 proteins had significantly altered expression in the treated cells. Enrichment analyses revealed that proteins associated to redox homeostsis, metabolism, and cellular energy generation were inhibited while, proteins related to DNA damage and repair and other stresses were over expressed. Altered activities of several tumor associated proteins were observed. Protein-protein interaction network and biological pathway analysis of these differentially expressed proteins were carried out to obtain a systems level view of proteome changes. Together it could be inferred that PM exposure induced oxidative stress which could have lead into DNA damage and tumor related changes. However, lowering of cellular metabolism, and energy production could reduce its ability to overcome these stress. This kind of disequilibrium between the DNA damage and ability of the cells to repair the DNA damage may lead into genomic instability that is capable of acting as the driving force during PM induced carcinogenesis.

8-Hydroxyquninoline Mannich base namely 7-diethylaminobenzyl-8-hydroxyqunioline(DEBQ) was synthesized and characterized by elemental analysis and spectral studies. Chelates of DEBQ with manganese(II) and nickel(II) were isolated and structurally characterized by elemental analysis, electrical conductance, magnetic susceptibility measurement, thermal analysis, IR,UV-Vis, EPR and Mass spectral data. The Mannich base ligand is bidentate and chelates through the phenolic oxygen and the aliphatic tertiary amino nitrogen atoms. Based on the magnetic and electronic spectral data all the MnII complexes are assigned an octahedral geometry and NiII complexes are assigned a tetrahedral geometry. Antimicrobial susceptibility screening of the Mannich base shows that it possesses excellent activity when compared to the standard drugs and the metal complexes studied. Among the chelates, MnII chelate is more potent than NiII chelate. Thermal analysis of a few compounds shows two stage decomposition patterns.

A series of substituted styryl 2-hydroxy-1-naphthyl ketones have been synthesized by crossed-Aldol condensation reaction. These ketones are characterized by their physical constants, IR and NMR data. The IR carbonyl stretching and deformation modes ν (cm−1) of vinyl portion frequencies and 1H and 13C NMR spectral chemical shifts δ (ppm) of ethylenic protons, carbons and carbonyl carbons are correlated with various Hammett sigma constants, field, and resonance and Swain–Lupton parameters by single and multi-regression analysis. From the statistical analysis the effect of substituents on the group frequencies is studied.

GTAW process is appropriate for joining slim and medium thickness materials like stainless steel sheets. Stainless steel 202 grade has wide applications in making consistent stainless steel tubes, super warmer cylinders, cook products and so forth., Angular distortion is one such imperfection that makes the work piece twist in angular ways around the weld interface. After welding treatment is required to take out the distortion so the work piece is defect free and acknowledged. The level of angular distortion is specifically affected by the welding input parameters amid the welding procedure; along these lines, welding can be considered as a multi input procedure. This paper presents advancement of an Artificial Neural Network (ANN) demonstrate to anticipate angular distortion for different input process parameters in 202 steel gas tungsten arc welded plates The picked info process parameters were welding gun angle, welding current, plate thickness, welding speed and gas flow rate. The picked yield parame...

The electro active inorganic-organic nanohybrid material Polyaniline-BaMnO3 has been synthesized by the surfactant assisted chemical polymerization reaction of aniline with nanocrystalline BaMnO3. Electrochemical studies have been performed using cyclic voltammetry and galvanostatic charge-discharge measurements. The enhanced electrode performance originates from the synergistic effect of PANI and BaMnO3. The hybrid delivers very high specific capacitance of 560.5 Fg-1, energy density of 32.01 whkg-1 and power density of 400 wkg-1, respectively. The hybrid also exhibits very high stability and excellent cycling performance with less than 5% capacity loss over 500 cycles.

Nature is perceived and valued in starkly different and oftenconflicting ways. This paper presents the rationale for theinclusive valuation of nature's contributions to people (NCP) indecision making, as well as broad methodological steps fordoing so. While developed within the context of theIntergovernmental Platform on Biodiversity and Ecosystem Services (IPBES), this approach is more widely applicable toinitiatives at the knowledge?policy interface, which require apluralistic approach to recognizing the diversity of values. Weargue that transformative practices aiming at sustainablefutures would benefit from embracing such diversity, which require recognizing and addressing power relationships across stake holder groups that hold different values on human nature relations and NCP Fil: Pascual, Unai. University Of Cambridge; Reino Unido Fil: Balvanera, Patricia. Universidad Nacional Autónoma de México; México Fil: Díaz, Sandra Myrna. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Pataki, György. Corvinus University of Budapest; Hungría Fil: Roth, Eva. University of Southern Denmark; Dinamarca Fil: Stenseke, Marie. University Goteborg; Suecia Fil: Watson, Robert T.. University of East Anglia; Reino Unido Fil: Basak Dessane, Esra. Project House; Turquía Fil: Islar, Mine. Lund University; Suecia Fil: Kelemen, Eszter. Environmental Social Science Research Group; Hungría Fil: Maris, Virginie. Centre d’Ecologie Fonctionnelle et Evolutive; Francia Fil: Quaas, Martin. Kiel University; Alemania Fil: Subramanian, Suneetha M. United Nations University; Japón Fil: Wittmer, Heidi. Helmholtz-Centre for Environmental Research; Alemania Fil: Adlan, Asia. University of Khartoum; Sudán Fil: Ahn, SoEun. Korea Environment Institute; Corea del Sur Fil: Al-Hafedh, Yousef S. King Abdulaziz City for Science & Technology; Arabia Saudita Fil: Amankwah, Edward. Center for Environmental Governance; Ghana Fil: Berry, Pam. University of Washington; Estados Unidos Fil: Bilgin, Adem. University of Oxford; Reino Unido Fil: Breslow, Sara J. Ministry of Forestry and Water Affairs of Turkey; Turquía Fil: Bullock, Craig. University College Dublin; Reino Unido Fil: Caceres, Daniel Mario. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias. Departamento de Desarrollo Rural; Argentina Fil: Daly-Hassen, Hamed. University of Carthage; Túnez Fil: Figueroa, Eugenio. Universidad de Chile; Chile Fil: van den Belt, Marjan. Victoria University of Wellington; Nueva Zelanda Fil: Verma, Madhu. Indian Institute of Forest Management; India Fil: Wickson, Fern. GenØk Centre for Biosafety, Siva innovasjonssenter; Noruega Fil: Yagi, Noboyuki. The University of Tokyo; Japón

We report trapping and recombination centers with an acceptor-like character VZn and their defect complex in unintentional hydrogen-doped ZnO nanoparticles using photoluminescence and electron para...

Body-in-White (BIW) is the Car Body without additional subsystems. Automakers are trying hard to reduce the mass of the vehicle body. The efficient option is to use multi materials and minimal number of parts in the BIW, in order to meet the stiffness requirements considering different load cases. Bending Analysis and Torsion Stiffness Analysis was performed to understand and assess the structural performance of the BIW. This paper presents the new BIW architecture with minimal number of parts, with an effective load path for the Structural and Crash load cases. Structural bending and torsion stiffness of the BIW were performed to evaluate the stiffness of the BIW to meet the passenger segment car. The methodology of using different materials for upper and under body has been investigated with the alternatives as Aluminium and Magnesium. BIW was analysed with Steel under body and Magnesium or Aluminium upper body. The Torsion stiffness of Steel/Magnesium BIW was found to be better than Steel/Aluminium BIW. The design concept with Steel underbody and Magnesium upper body was giving lighter weight design with better structural stiffness as compared to the Steel/Aluminium body. This approach of modifying the materials for the upper body of the BIW can be considered as lightweight solutions in other Conceptual BIW designs.

The present work investigates the relation between ferromagnetism and intrinsic defects of C-doped ZnO thin films. The room-temperature ferromagnetism (RTFM) in C-doped ZnO is due to the charge transfer between Zn 4s and C 2p orbitals. The long-range magnetic interaction in C-doped ZnO is due to carbon–carbon interaction mediated by oxygen. The oxygen- and zinc-related defects in C-doped ZnO affect the mediation of ferromagnetic interaction and the existence of hybridization between Zn and C, respectively.

A single amorphous carbon nanofiber (CNF) was grown on a commercial Si cantilever by the argon ion (Ar+) bombardment of carbon coated silicon cantilever. The CNF probe was mounted on a piezo controlled arm opposing a soft cantilever to measure the axial force acting on the CNF in a scanning electron microscope (SEM). The buckling force was measured while observing the buckling behavior. The CNF probes have an elliptical cross section with short and long axis of 20–29 and 25–59 nm, respectively, and a length of 350–760 nm. The Young’s modulus was determined from Euler’s formula using the measured buckling force and had a value of 38–48 GPa, almost independent of the CNF size. The Young’s modulus was lower than that of high quality carbon nanotubes (CNTs) and higher than that of defective CNTs. It was also demonstrated that the CNF probes were elastic, similar to the CNT probes. Thus CNF probes produced by Ar+ ion bombardment are quite promising as practical nanocarbon probes.

The segmentation of retinal blood vessels and optical disc is the most vital and challenging task to investigate the rigorousness of the various retinal diseases such as branch retinal vein occlusion. There are lot of methods and algorithms are developed to address this issue i.e., for the precise segmentation of optical disc and blood vessels. However, every method has its own pros and cons. Retinal vein occlusion (RVO) happens due to the obstruction (blockage) of veins transporting blood with required nutrients and oxygen to the nerve cells in the eye's retina. An obstruction in any one of the four smaller branch veins is referred to as a branch retinal vein occlusion (BRVO). It is one of the main retinal illnesses next only to diabetic retinopathy. Our proposed approach is a simple image processing based detection of optical disc and retinal blood vessels of branch retinal vein occluded fundus images.

A390+X vol.% ZrO2 (X = 5, 10, 15) composites have been fabricated through P/M technique. The mixed aluminium alloy and zirconium oxide powders were cold compacted at 200 MPa and sintered at 580°C for 3 h. The influence of ZrO2 reinforcement on microstructure, physical, and electrochemical behaviour of fabricated composites were examined. The results convey that the composites have relative density of 99%. Potentio dynamic polarisation studies on A390 and A390+Xvol.% ZrO2 composites in 3.5 wt.% of NaCl solution revealed that the addition of ZrO2 in Al alloy shifts the corrosion potentials towards positive direction. The increase of ZrO2 content in A390 alloy increases the corrosion current density due to the expansion in particle-matrix interface area. The research goal is to develop a new metal matrix composite material, by powder metallurgy (P/M) technique and experimentally investigate the various mechanical, physical properties and corrosion study, for ensuring that the developed material could be used in pistons.

Dielectric relaxation behaviour in polar–polar mixtures of anisole and isopropyl alcohol in benzene has been observed using the measurements of dielectric permittivity and dielectric loss at microwave frequency at three different temperatures. Using the Higasi method, average relaxation time, relaxation time for intra-molecular rotation and inter-molecular rotation have been calculated for the mixtures at different compositions. Viscosity and density of the mixtures are obtained over the entire range of concentration and temperature studied. Thermodynamic parameters, such as enthalpy and entropy, have been calculated for all studied concentrations, i.e. pure liquids and their mixtures. Activation free energies due to dielectric relaxation and viscous mechanisms for the system are discussed.

The permittivity and the dielectric loss of ternary mixtures of equimolar concentrations of m-cresol, o-cresol with acetonitrile, acrylonitrile and benzonitrile in benzene have been measured at 8.33 GHz and 308 K. The distribution parameter α, the most probable relaxation time τ, the relaxation time for overall rotation of the molecule τ(1), the relaxation time for group rotation τ(2), and the excess dipole moment for various systems have been calculated by the Cole-Cole and Higasi methods. Data has been analyzed in terms of two-relaxation processes: overall rotation and group rotation.

Pure and cobalt doped titanium dioxide thin films have been prepared on glass and Si (100) substrates by sol–gel spin coating method. The structural and optical properties of the films as a function of cobalt concentration (up to 15 wt.%) have been systematically studied by Rutherford backscattering spectroscopy, X-ray diffraction, Raman spectroscopy, scanning electron microscopy, optical spectroscopy and spectroscopic ellipsometry methods. Rutherford backscattering studies show the presence of cobalt dopant in the films is almost equal to the precursor stoichiometry. Grazing incidence X-ray diffraction and Raman spectroscopy studies confirm the amorphous phase of the as-deposited films and crystalline anatase phase for the films annealed at 600 °C. The optical spectroscopy measurements show that the films are fully transparent in the visible region and there is a band gap narrowing upon increasing cobalt dopant concentration. The refractive index, band gap ( E g ) and thickness of the films were determined from spectroscopic ellipsometry measurements. The refractive index of the films was found to increase from 2.2 to 2.7 with the increase in cobalt concentration with a simultaneous decrease of band gap from 3.1 to 2.8, which is favorable for photocatalytic applications. The packing density of the films was calculated by Clausius–Mossotti relation and is found to increase with cobalt concentration.

The pulsed electrodeposition method was applied for the preparation of Co and Co–Ni alloy. Pulse duty cycles of 5 to 80% at frequencies 10 to 100 Hz with current densities ranging from 2·5 to 7·5 A dm−2 were employed. The influence of pulse current density, duty cycle and frequency on the thickness and hardness of the Co and Co–Ni deposit were studied. Corrosion resistance of Co and Co–Ni alloy is compared in the present paper.

Nickel electrodeposits were formed directly on to AA 1100 aluminium alloy using a simple chemical pretreatment both by direct current plating (DCP) and pulsed current deposition (PCD) methods in the absence and presence of α-picoline and quinoline. In dc plating the current density was varied between 1 and 4 A dm−2. In pulse plating, the current density was varied between 1 and 4 A dm−2 and the duty cycle was varied between 10 and 80% at the frequency of 100 Hz. The throwing power and current efficiency of the bath were determined. The influence of current density, duty cycle, α-picoline and quinoline on throwing power and current efficiency of the bath during direct and pulse current plating have also been studied.

Synthesis of (1RS, 2SR)-(±)-2-amino-1-phenyl-1-propanol (2) by reductive animation of (R)-(−)-1-hydroxy-1-phenyl-2-propanone (1) using ammonia and Raney nickel as a catalyst was investigated. Compound 1 was produced by fermentation of molasses with a strain of yeast and benzaldehyde was added during the course of fermentation.

Some azomethines including substituted benzylidene-4-chlorobenzenamines ( E -imines) have been synthesized by fly-ash: PTS catalyzed microwave assisted condensation of 4-chloroaniline and substituted benzaldehydes under solvent-free conditions. The yield of the imines has been found to be more than 85%. The purity of all imines has been checked using their physical constants and UV, IR and NMR spectral data. These spectral data have been correlated with Hammett substituent constants and F and R parameters using single and multi-linear regression analysis. From the results of statistical analysis, the effect of substituents on the above spectral data has been studied. The antimicrobial activities of all imines have been studied using standard methods. KEY WORDS : Solvent-free synthesis, Fly-ash: PTS, Aryl imines, Spectral correlations, Antimicrobial activities Bull. Chem. Soc. Ethiop. 2015 , 29(2), 275-290 DOI: http://dx.doi.org/10.4314/bcse.v29i2.10

Bismuth titanate thin films co-modified by La and Nd, Bi3.15(La0.425Nd0.425)Ti3O12 (BLNT) were grown on Pt/Ti/SiO2/Si(100) substrates by metalorganic solution decomposition method. The co-substitution leads to structural distortion with enhanced remanent polarization. The BLNT film capacitor with a top Pt electrode showed a large remanent polarization (2Pr) of 90 μC/cm2 at an applied voltage of 10 V, which is higher than that of highly c-axis oriented BLT, and comparable with BNdT thin films. The BLNT films exhibited a fatigue-free behavior up to 1×109 switching cycles at a frequency of 1 kHz. These experimental results reveal that BLNT thin films can be used as capacitors in ferroelectric random access memory applications.

Cell-cell signaling roles for reactive oxygen species (ROS) generated in response to growth factors/cytokines in nonphagocytic cells are not well defined. In this study, we show that fibroblasts isolated from lungs of patients with idiopathic pulmonary fibrosis (IPF) generate extracellular hydrogen peroxide (H2O2) in response to the multifunctional cytokine, transforming growth factor-beta1 (TGF-beta1). In contrast, TGF-beta1 stimulation of small airway epithelial cells (SAECs) does not result in detectable levels of extracellular H2O2. IPF fibroblasts independently stimulated with TGF-beta1 induce loss of viability and death of overlying SAECs when cocultured in a compartmentalized Transwell system. These effects on SAECs are inhibited by the addition of catalase to the coculture system or by the selective enzymatic blockade of H2O2 production by IPF fibroblasts. IPF fibroblasts heterogeneously express alpha-smooth muscle actin stress fibers, a marker of myofibroblast differentiation. Cellular localization of H2O2 by a fluorescent-labeling strategy demonstrated that extracellular secretion of H2O2 is specific to the myofibroblast phenotype. Thus, myofibroblast secretion of H2O2 functions as a diffusible death signal for lung epithelial cells. This novel mechanism for intercellular ROS signaling may be important in physiological/pathophysiological processes characterized by regenerating epithelial cells and activated myofibroblasts.

Second-order rate constants (k2) of the reaction between phenacyl bromide and equimolar mixture of nitrobenzoic acid(s)–triethylamine have been determined in dimethylformamide (DMF)/acetonitrile (ACN)/acetone and aqueous mixtures of these solvents by conductometric method at 30°C. The rates of nitrobenzoic acids are found to be in the order: 4-NO2 > 3-NO2 > 3,5-(NO2)2. Changes in the rate just by the addition of water (1% (v/v)) into organic component is rationalized. Decrease in the values of k2 on increasing water content in organic solvent is explained on the basis of preferential solvation phenomenon. Single and dual regression analysis using the various solvent parameters of aqueous mixtures (ET(30), Z, π*, β, α, and Y) resulted in π* and α as the best parameters to explain solvation of nitrobenzoates. © 2004 Wiley Periodicals, Inc. Int J Chem Kinet 36: 401–409, 2004

The determination of the structure and properties of associated liquids could provide deeper insight into the phenomena of the molecular interactions and is of great importance in biology and chemical physics. The IR and NMR spectroscopic methods were extensively used for determining the nature of association. However, these methods could give only circumlocutory information regarding the alignment of neighbouring molecules. This vital information could be obtained from dielectric measurements by virtue of the influence of local order and the overall dipole moment. In dilute solutions of alcohols with inert solvents, the interaction between the solute species among themselves may be given by a modified form of the correlation factor (g′) taking the solute-solvent and solvent-solvent interaction. Dielectric constant of the binary mixtures of 1-hexadecanol, 1-tetradecanol, 2-ethyl-1-hexanol and 2-ethoxyethanol in benzene were determined at 298K, 308K and 318K. The presence of α and β multimers in the above systems were identified and the results are interpreted accordingly.

The identification of retinal blood vessels is very important but crucial task to analyze the severity of the retinal diseases such as diabetic retinopathy, macular degeneration, central retinal vein occlusion, central retinal artery occlusion, retinal detachment and branch retinal vein occlusion. It is evident that huge number of computer based automated algorithms are developed for the accurate detection of blood vessels and optical disc. Most of the work utilizes the retinal fundus images in RGB color space. The proposed work implements the detection and segmentation of retinal blood vessel in RGB and device independent CIELUV color space. The proposed work for the segmentation retinal blood vessel is based on adaptive histogram equalization, median filtering and morphological operations.

Among short-range molecular interactions, the molecular complexes formed by hydrogen bond attracted the attention to understand the nature of the bond. Theoretical studies concluded that redistribution of charges due to polarization and charge transfer effects accompanies the molecular interaction. This phenomenon of charge redistribution can be related to the changes in the dipole moment of the complex systems to those of isolated molecules. The dipole moments of 1:1 complexes of acetonitrile and acrylonitrile with o-cresol in benzene and ethylene glycol and diethylene glycol in 1,4 dioxan were determined at 308 K using Huyskens method based on Onsager's theory. The dipolar increments for these systems were computed from the bond angle data available from molecular orbital studies. Our results show that the polarization interaction dominates in all the complexes studied and no higher order complexation is indicated.

The supercritical fluid extraction (SFE) of bitumens from four major Uinta Basin (Utah) oil sand deposits was studied with propane solvent. The deposits studied included Whiterocks, Asphalt Ridge, PR Spring and Sunnyside. The bitumens from these deposits differed widely in physical and chemical properties. The volatilities (components with boiling point n -pentane insolubles) were 2.9, 6.8, 19.3 and 23.6 wt.% for the Whiterocks, Asphalt Ridge, PR Spring and Sunnyside bitumens, respectively. The SFE experiments were carried out at five conditions, combinations of three different pressures (5.6 MPa, 10.4 MPa, and 17.3 MPa) and three temperatures (339 K, 380 K and 422 K). The cumulative extraction yield increased with increase in solvent density at all operating conditions for the four bitumens. A maximum yield of 45 wt.% was obtained at the highest solvent density with the Whiterocks bitumen. The extraction products were significantly upgraded liquids relative to the bitumens. Comparatively lighter fractions were extracted in the earlier stages of extraction for all the four bitumens, whereas heavier extracts were obtained at higher extraction-solvent densities. The asphaltene contents of the residual fractions were significantly higher than the asphaltene contents predicted on a prorated basis for all four bitumens. This trend was due to the extraction of cosolubilizing components that kept the asphaltenes in suspension in the bitumen. It was concluded that solute polarity played a significant role in the extraction yields of the four bitumens. The Whiterocks bitumen, which was the least polar bitumen based on asphaltenes content, gave higher extraction yields compared to the bitumens from the other three deposits at all five operating conditions. The Sunnyside bitumen with the highest asphaltene content gave the lowest extraction yield at all five conditions. The Asphalt Ridge and PR Spring bitumens with intermediate polarity (based on asphaltene content) gave intermediate extraction yields with the Asphalt Ridge bitumen extraction yields higher than the PR Spring bitumen. Preliminary modeling of the extraction process using the Peng–Robinson cubic equation of state and a pseudocomponent lumping scheme provided a reasonable match with the experimental data for Whiterocks and PR Spring bitumens.

Susceptibility of four major rat tissues to oxidative damage in terms of lipid peroxidation induced by in vitro by ascorbate-Fe2+ in homogenates and mitochondria has been examined. Lipid peroxidation, as assessed by thiobarbituric acid reactive substances (TBARS) and conjugated dienes was maximum in brain followed by liver, kidney and heart. However, the time course of lipid peroxidation showed different patterns in tissues examined. The higher susceptibilities of brain and liver can be explained by substrate availability and to a lesser extent the level of antioxidants. The differences observed in the tissues studied may reflect their susceptibility to degenerative diseases and xenobiotic toxicity which are considered as a result of oxidative damage to membranes.

Th e America n Society for Testing Materials (ASTM ) procedures D2887 and D5307 are used for boiling range characterization of petroleum fractions up to 538°C (1000°F). Th e bitumens fro m the Uint a Basin (Utah ) contain approximatel y 60.0 wt % material boiling above 538°C (1000°F); hence, the AST M techniques leave major portions of the bitumens uncharacterized . A hightemperature chromatographi c technique is developed to include a portio n of the high-boiling-point compound s (greater than 538°C or 1000°F) in bitumen-derive d heav y oils. A short 5-m glass capillary colum n is used to elute compound s wit h boiling points as high as 700°C (1292°F) (equivalent to C 90 ). Analyses of Uint a Basin (Utah ) bitumens and bitumen-derive d extract phases and residues are reported using the modified procedure . Th e characterization of the samples is extende d by 30–35 wt % using the proposed simulated distillation method .

Defect and impurity associate wide band gap semiconductor ZnO are potential impact in the field of quantum information science, optoelectronic, atomic transport and cancer treatment process. In ZnO, zinc vacancies (VZn) are tetrahedrally surrounded by four O2− in the basal plane. Suppose the substituted hydrogen (HO) or interstitial hydrogen (Hi) bound with VZn leads to provide different paramagnetic nature. At room temperature, two electron paramagnetic resonances (EPR) donor signals overlapping at g 1.9573 and of 77 K the peaks are distinguish at 1.9562 and 1.96. At 77 K, (i) both the peak intensities are increases indicates that the increases of paramagnetic behavior by reducing temperature (ii) the peak intensity observed at 1.9562 is strongly increased upon uν illumination with increases of uncompensated electron spin from acceptor to donor level. Similarly, acceptor related paramagnetic signals observed at 2.0138 and 2.0044 under uν illumination at 77 K, because the concentration of the donor is hig...

Lipid peroxidation, one of the most common expressions of oxidative stress, may be altered during normal physiological states including development. We have examined the changes in lipid peroxidation in rat brain, a tissue highly susceptible to oxidative damage, during this physiological state. In vivo lipid peroxidation was moderate in the foetal and neonatal period and increased during the postnatal development. Lipid peroxidation potential in brain homogenate and mitochondria, in Tris-HCl buffer or with exogenous cofactors, such as ascorbate-Fe2+, NADPH ADP-Fe3+ and cumene hydroperoxide, showed significant changes during pre- and postnatal development. In general, brain as well as liver (used as a standard tissue for comparison) seem to have low peroxidation potential in the foetal and neonatal period which then increases at different rates during development to reach adult values at different days. The low peroxidation potential corresponds to the rapid phase of cell proliferation. These results taken together with similar earlier finding in other systems may indicate a possible occurrence of a 'permissible period' during which the low levels of lipid peroxidation may be able to yield only low amounts of cytostatic aldehydes and peroxides as byproducts, thereby allowing rapid proliferation of cells.

Batch photocatalytic degradation studies of phenol were conducted in an annular slurry reactor, to evaluate its performance under different operating and design conditions. The reactor had two concentric cylinders with the inner one rotating at specified revolutions per minute. The reactor also had provisions for aerating the slurry present in the annular gap. The inner cylinder housed the UV-lamps. The effects of catalyst loading (0-8 g/L), inner cylinder rotation speed (0-50 rpm), annular gap-width (7.5, 17.5 and 32.5 mm), initial pollutant concentration (10-50 mg/L) and mode of illumination (continuous or periodic) were studied. Light intensity received by the slurry was measured using Actinometry. Depending on the catalyst loading, annular gap-width and number of illuminated lamps the intensity values ranged from 0.58�10 -4 to 6.4�10 -4 Einsteins/L min. Under well mixed conditions, the reactor performance was found to increase with increase in catalyst loading. At low/medium annular gap width configurations, agitation induced by continuous aeration was found to provide sufficient mixing even when the inner cylinder was stationary. Rotation of the inner cylinder was required only in the high gap width configuration at high catalyst loadings. Scale-up of the reactor was investigated by increasing the gap-width of the annulus and hence increasing the quantity of feed processed. Controlled periodic illumination created by Taylor vortices did not show any improved performance over the regular continuous illumination. Modeling of reaction kinetics was investigated with different approaches and their efficacy in fitting the concentration-time trends of both the primary pollutant and the intermediates are discussed. � 2010 Elsevier Ltd. All rights reserved.

Treatment of substituted o-hydroxychalcones 1-3 with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone [DDQ] afforded a mixture of chromenochalcones 4-6 (pongachalcone I [5a], glabrachromene [5d]), aurones 7-9 and flavones 10-12. A new and convenient synthesis of candidin [17a], atalantoflavone dimethylether [17b], racemoflavone dimethylether [17d], mixtecacin [20a], and their derivatives via the corresponding unknown dihydropyranoflavanones 13-15 has also been described

Reaction of 4-hydroxy-3-prenylquinolin-2(1 H)one (5 a) with iodine and silver acetate gave a iodopyranoquinoline (6 a), which was then converted into the alkaloids khaplofoline (1) and ribalinine (2). Reaction of 5a with iodine and mercuric oxide afforded a mixture of 6a and its angular isomer 7 a; the coversion of latter into flindersine (10) is described.

Catalyst loading is an important parameter that needs to be optimized in the operation of photocatalytic slurry reactors. In this study on photocatalytic degradation of phenol, the optimum catalyst loading was found to depend mainly on the dissolved oxygen (DO) concentration in the aqueous solution, especially at higher irradiation intensities. The estimated Langmuir-Hinshelwood (L-H) kinetics constants were found to vary with light intensity and dissolved oxygen concentration. The intermediate products of photocatalytic oxidation were identified. � 2008 Springer.