Molecular interaction of quinoline with coal-liquid fractions

A direct calorimetric method has been used to determine simultaneously the molar enthalpy, ΔH^o, and equilibrium constant, K, for the interaction of quinoline (Qu) with coal-derived asphaltenes (A), acid/neutral (AA) and base (BA) components of A, silylated asphaltenes (A(TMS)) and heavy oil (HO) fractions in solvent C₆H₆. Solvent fractionated A and HO fractions were from three centrifuged-liquid product (CLP) samples prepared in the 450 kg ($\text{≈}\text{1}\text{2}$ U.S. ton) per day Process Development Unit at Pittsburgh Energy Research Center, at different process conditions from the same feed coal, Kentucky hvAb. For a given system, Qu-A (AA or BA), Qu-HO, the almost constant value of K and rectilinear variation of ΔH^o with the phenolic oxygen content of coal-liquid fractions have been attributed to the dominance of hydrogen-bonding effects, involving phenolic OH, over other types of molecular interactions in solution. In the Qu-A(TMS) system, ?ΔH^o values increase with decrease in molecular weight of A(TMS), while ?ΔS^o values increase with increase in aromaticity of the A fraction. The degree of complexation, in absence of OH groups, is much smaller than with the Qu-A system.     

Dual Critical Points and Related Phenomena in Simple Fluids from the Perspective of (Approximate) Renormalization Theory

It is known that some single component fluids can have coexisting low-density and high-density liquid phases with two, separate, gas–liquid and liquid–liquid, critical points. Such behavior is found both by experiments and in recent molecular-dynamics simulations performed for certain simple isotropic attractive pair potentials with softened repulsive cores. In the present investigation, a global renormalization group theory that was employed previously to make predictions for simple Lennard–Jones and square-well fluids over wide ranges of density and temperature, including the critical point, in reasonably good agreement with molecular dynamics and Monte Carlo simulations, is applied to simple shoulder potentials and to square-well potentials with softened repulsive cores. Results using this renormalization approach are compared with some previously reported results for a shoulder potential and expectations regarding dual critical points for water.     

Synthesis of WO3 in nanoscale with the usage of sucrose ester microemulsion and CTAB micelle solution

WO₃ nanoparticles were successfully prepared using first the low temperature hydrolysis method and second the chemical reaction method in water-in-oil sucrose ester microemulsion consisting of S1570, 1-butanol, tetradecane and aqueous phase. In this study WO₃ nanoparticles also were prepared using the CTAB micelle solution. The resultant WO₃ nanoparticles have been investigated with X-ray diffraction (XRD), transmission electron microscopy (TEM), variable pressure scanning electron microscope (SEM) equipped with energy dispersive X-ray analysis (EDX) and X-ray photoelectron spectroscopy (XPS). The shape and particles size of the resultant WO₃ nanoparticles from both methods in sucrose ester microemulsion show similar spherical shape and size range between 10 and 50 nm. The WO₃ nanoparticles prepared with the CTAB micelle solution show spherical shape with the size range average of 25-50 nm.     

Nanoscale silver cluster embedded in artificial heterogeneous matrix consisting of protein and sodium polyacrylate

Nanoscale silver cluster protected by sodium polyacrylate (PAA) was prepared through the reduction of aqueous silver nitrate solution containing PAA. PAA concentration was varied against a fixed concentration of silver nitrate to optimize the PAA to metal ratio, in which stable colloidal solution of silver nanoparticles of 7 ± 3 nm size could be obtained. These PAA-protected silver nanoparticles in clusters of nanoscale dimension (nanoclusters) were dispersed into the artificial heterogeneous matrix fabricated from aqueous solution of polyacrylate and protein (bovine serum albumin, BSA) by adjusting the pH in the acidic region. PAA-protected Ag-nanoparticle and Ag/PAA-BSA composites were characterized by UV-VIS spectroscopy and TEM.     

Effect of amount, size, and spatial distribution of intermetallics on incipient localization during plastic deformation

Virtual microstructures having a systematic variation of amount, mean size, standard deviation of size, and spatial arrangement of intermetallics have been synthesized, and their deformation behavior in uniaxial tension has been evaluated using finite element analysis. Four spatial arrangements of intermetallics have been considered in this work, namely: random, clustered, and two-ordered structures. Various mathematical quantities have been developed to quantify the severity of deformation including plastic work density distribution (PWDD), percentile work-density volume criterion (PWC), and percentile stress volume criterion (PSC). This approach eliminates the need for an external trigger in FEA to achieve localization. The method developed has led to a better understanding of the effect of different microstructural attributes on the process of deformation. This has resulted in guidelines for optimizing the microstructure to minimize material damage and thereby maximize ductility.     

International Symposium on Wearable Computing (ISWC) 2008

The 12th International Symposium on Wearable Computing (ISWC) was held in Pittsburgh in September 2008. It is one of the longest-running conferences focusing on aspects of pervasive and mobile computing. With over 60 submissions, the program committee selected eight long papers, seven short papers, and nine posters for the conference (a 26 percent acceptance rate for long papers). Sessions, which were presented over two days, covered location mapping, mobile phones and human interfaces, activity recognition, activity support, and power and system integration.     

Note-against-note two-voice counterpoint by means of fuzzy logic

In this study, we propose a fuzzy logic based approach for the ‘harmonization with constraints’ problem in music. After the mathematical modeling of the harmonization problem, the solution is carried out by means of proper fuzzy membership functions depending on the rules imposed by the music theory. To demonstrate the applicability of the proposed technique, particular problems of note-against-note two-voice counterpoint are considered. The method is flexible, adaptable and simple in terms of implementation. Moreover, from the constraint satisfaction perspective, the solutions generated by the method satisfy ‘arc-consistency’; which could not have been achieved by majority of the previous studies existing in the literature. The method also provides a gateway for the arranger/composer to incorporate his/her own stylistic preferences to the solution by simply adjusting the shapes of the membership functions. Additional features (such as providing variability in the final solutions at different executions) increase the power of the method in terms of creativity. This approach can be extended for the solution of more complicated problems in music such as orchestration, improvisation, and even composition.     

Formation of Hybrid Inorganic/Organic Nanocomposites

Hybrid inorganic/organic nanocomposites were produced by the exposure of spun films of octa-(benzo-15-crown-5)-substituted phthalocyanine of Cd(II) to an environment of hydrogen sulfide gas. The formation of cadmium sulfide (CdS) quantum dots in the metal free phthalocyanine matrix was identified in the phthalocyanine matrix from atomic force microscopy images. The mean size of CdS quantum dots was estimated to be 2–3 nm, from optical absorption and Raman spectra for the nanocomposites.     

Vanadium pentoxide: Synthesis and characterization of nanorod and nanoparticle V2O5 using CTAB micelle solution

Using a surfactant-mediated method (surfactant based on cetyltrimethyl ammonium bromide, CTAB) V₂O₅ nanorod and nanoparticles have been successfully prepared. Morphologies of V₂O₅ nanostructures can be controlled by applying different precursors and by varying reaction conditions within the CTAB soft template. With ammonium metavanadate and sulfuric acid as precursors, nanoparticles are synthesized in the size range of 45–160 nm. Precursors of vanadyl sulfate hydrate and sodium hydroxide yield vanadium pentoxide nanorods with diameters of 30–90 nm and lengths of 260–600 nm. The resulting products are characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), variable pressure scanning electron microscopy (VPSEM) and X-ray photoelectron spectroscopy (XPS). Temperature programmed reduction (TPR) is included to test catalytic performance. The results show that V₂O₅ nanoparticles and nanorods achieve better catalytic performance compared to bulk V₂O₅, i.e. lower onset temperature, workability at lower temperatures, and higher H₂ consumption (μmol/g).