An analytical equation of state for mercury

This paper presents a procedure for predicting the equation of state of mercury, by including mercury in the scope of a new statistical mechanical equation of state that is known for normal fluids. The scaling constants are the latent heat of vaporization and the density at the melting temperature, which are related to the cohesive energy density. Since experimental data for the second virial coefficient of mercury are scarce, a corresponding-states correlation of normal fluids is used to calculate theB(T) of mercury. The free parameter of the ISM equation, λ, compensates for the uncertainties inB(T). Also, we can predict the values of two temperature-dependent parameters, α(T) andb(T), with satisfactory accuracy from a knowledge of ΔH _vap andp _m, without knowing any details of the intermolecular potentials. While the values ofB(T) are scarce for mercury and the vapor pressure of this metal at low temperatures is very small, an equation of state for mercury from two scaling parameters (ΔH _vap,p _m) predicts the density of Hg from the melting point up to 100° above the boiling temperature to within 5%.     

Encapsulation of palladium nanoparticles by multiwall carbon nanotubes‐graft‐poly(citric acid) hybrid materials

Citric acid was polymerized onto the surface of functionalized multiwall carbon nanotubes (MWCNT‐COOH) and MWCNT‐graft‐poly(citric acid) (MWCNT‐g‐PCA) hybrid materials were obtained. Due to the grafted poly(citric acid) branches, MWCNT‐g‐PCA hybrid materials not only were soluble in water but also were able to trap water soluble metal ions. Reduction of trapped metal ions in the polymeric shell of MWCNT‐g‐PCA hybrid materials by reducing agents such as sodium borohydride led to encapsulated metal nanoparticles on the surface of MWCNT. Herein palladium nanoparticles were encapsulated and transported by MWCNT‐g‐PCA hybrid materials (MWCNT‐g‐PCA‐EPN) and their application as nanocatalyst toward Heck reaction in different conditions was investigated. The catalytic activity of palladium ions supported by MWCNT‐g‐PCA hybrid materials (MWCNT‐g‐PCA‐PdCl₂) toward Heck reactions is much more than for MWCNT‐g‐PCA‐EPN. Structure, characteristics and catalytic activity of synthesized systems was investigated using spectroscopy and microscopy methods. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Synthesis,characterization, and properties of novel poly(ether urea)s

Two diamines, 2,6‐bis(4‐aminophenoxy)pyridine and 2,6‐bis(5‐amino‐1‐naphenoxy)pyridine, were prepared through the nucleophilic aromatic substitution reaction of 4‐aminophenol and 5‐amino‐1‐naphthol, respectively, with 2,6‐dichloropyridine. Poly(ether urea)s were synthesized through the polyaddition reactions of these diamines with aromatic, semiaromatic, and cycloaliphatic diisocyanates. All the monomers and polymers were fully characterized, and physical properties of the polymers, including the thermal behavior, thermal stability, solubility, and solution viscosity, were studied. The polyureas showed improved thermal stability. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 961–965, 2004     

Preparation of novel pyridine‐based,thermally stable poly(ether imide)s

Two aromatic, pyridine‐based ether diamines were prepared by the nucleophilic aromatic substitution reaction of 4‐aminophenol and 5‐amino‐1‐naphthol with 2,6‐dichloropyridine in N‐methyl‐2‐pyrrolidone as a solvent. Polycondensation reactions of the obtained diamines with pyromellitic dianhydride, benzophenone tetracarboxylic dianhydride, and hexafluoroisopropylidene diphthalic anhydride resulted in six pyridine‐based, thermally stable poly(ether imide)s. The prepared monomers and polymers were characterized by common spectroscopic methods. The physical and thermal properties of the polymers, including the thermal behavior, thermal stability, solubility, and solution viscosity, were studied. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 22–26, 2004     

Linking fresh paste microstructure,rheology and extrusion characteristics of cementitious binders for 3D printing

Cementitious binders amenable to extrusion-based 3D printing are formulated by tailoring the fresh microstructure through the use of fine limestone powder or a combination of limestone powder and microsilica or metakaolin. Mixtures are proportioned with and without a superplasticizer to enable different particle packings at similar printability levels. A simple microstructural parameter, which implicitly accounts for the solid volume and inverse square dependence of particle size on yield stress can be used to select preliminary material combinations for printable binders. The influence of composition/microstructure on the response of pastes to extension or squeezing are also brought out. Extrusion rheology is used in conjunction with a phenomenological model to better understand the properties of significance in extrusion-based printing of cementitious materials. The extrusion yield stress and die wall slip shear stress extracted from the model enables an understanding of their relationships with the fresh paste microstructure, which are crucial in selecting binders, extrusion geometry, and processing parameters for 3D printing.     

Identifying Periodical Activities Independent of Video Content

In this research, a completely new and accurate method has been presented for detecting periodic activities with the help of machine vision. The proposed method is independent of motion tracking complex algorithms unlike the previous strategies and it is fully independent of contents and types of activities by performing low level calculation. Not using of heavy computations while improving the ability of periodicity detection is regarded as the unique feature of this method. The use of general and flexible framework in this method causes to facilitate the machine vision periodic activities identification process.     

Product yields for the photofission of ~(232)Th,~(234,238)U,~(237)Np,and ~(239,240,242)Pu actinides at various incident photon energies

Photofission fragments mass yield for~(232)Th,~(234;238) U,~(237) Np, and~(239;240;242) Pu isotopes are investigated.The calculations are done using a developed approach based on Gorodisskiy's phenomenological formalism. The Gorodisskiy's method is developed to be applied for the neutron-induced fission. Here we revised it for application to photofission. The effect of emitted neutron prior to fission on the fission fragment mass yields has also been studied. The peak-to-valley ratio is extracted for the240 Pu isotope as a function of energy. Obtained results of the present formalism are compared with the available experimental data. Satisfactory agreement is achieved between the results of present approach and the experimental data.