Non-Metallic Inclusions in Carbon Steel Containing Rare Earth Metals

The effect of rare earth metals (RE) on composition of carbon steel and the quantity, size and morphologies of inclusions were experimentaly determined. Optical scann-ing electron microscopy and X-ray diffraction analysis as well as empirical calculations resulted that the RE affected the chemical composition of carbon steel and inclusions. The sulphur content did not vary. The inclu-sion quantity was increased. The RE modified inclusions, especially sulphides into small-smooth size under 4um. The steels containing from 0.01% to 0.02%RE have develo- ped globular oxysulphide inclusions of lb type, where as steels containing from 0.04% to 0.043% RE contain angular sulphide inclusions of Illb type. When the RE content in steel was over 0.062%RE harmful cluster sulphide inclu-sions of IV type was formed.Thus it was concluded that the RE beneficial affected the formation and modification of non-metallic inclusions in carbon steel

A continuum-microscopic method based on IRBFs and control volume scheme for viscoelastic fluid flows

A numerical computation of continuum-microscopic model for visco-elastic flows based on the Integrated Radial Basis Function (IRBF) Control Volume and the Stochastic Simulation Techniques (SST) is reported in this paper. The macroscopic flow equations are closed by a stochastic equation for the extra stress at the microscopic level. The former are discretised by a 1D-IRBF-CV method while the latter is integrated with Euler explicit or Predictor-Corrector schemes. Modelling is very efficient as it is based on Cartesian grid, while the integrated RBF approach enhances both the stability of the procedure and the accuracy of the solution. The proposed method is demonstrated with the solution of the start-up Couette flow of the Hookean and FENE dumbbell model fluids

Relationships between interlibrary loan and research activity in Canada

Interlibrary Loan borrowing rates in academic libraries are influenced by an array of factors. This article explores the relationship between interlibrary loan borrowing activity and research activity at 42 Canadian academic institutions. A significant positive correlation was found between interlibrary loan borrowing activity and measures of research activity. The degree of correlation observed depended on the category of institution, with undergraduate and comprehensive universities showing the largest correlations. This is the first study to quantify the relationship between interlibrary loan and research activity, and the findings suggest that interlibrary loan plays a role in supporting academic research at Canadian universities

An analysis of direct reciprocal borrowing among Québec university libraries

An analysis of Quebec academic libraries’ direct reciprocal borrow- ´ ing statistics from 2005 to 2010 reveals that the physical distance separating universities plays an important role in determining the amount of direct reciprocal borrowing activity conducted between institutions. Significant statistical correlations were also seen between the amount of direct reciprocal borrowing/lending as well as institution size and library collection size. Given their proximity, Montreal-area libraries have a higher ratio of direct reciprocal bor- ´ rowing activity compared to interlibrary loan consortial borrowing activity, whereas libraries located outside of Montreal have higher ´ interlibrary loan activity compared to direct reciprocal borrowing. It was found that institutions’ net lender and borrower status can shift depending on whether one is looking at direct reciprocal borrowing versus interlibrary loan activity. An exploratory social network analysis of direct reciprocal borrowing among Quebec ´ academic libraries was performed, and it affirmed the important role of physical distance in determining direct reciprocal borrowing activity. Language may also play a role in affecting the amount of direct reciprocal borrowing

A Comprehensive View of Circumstellar Disks in Chamaeleon I: Infrared Excess, Accretion Signatures and Binarity

We present a comprehensive study of disks around 81 young low-mass stars and brown dwarfs in the nearby ~2-Myr-old Chamaeleon I star-forming region. We use mid-infrared photometry from the Spitzer Space Telescope, supplemented by findings from ground-based high-resolution optical spectroscopy and adaptive optics imaging. We derive disk fractions of 52 (+/-6) % and 58 (+6/-7) % based on 8-micron and 24-micron colour excesses, respectively, consistent with those reported for other clusters of similar age. Within the uncertainties, the disk frequency in our sample of K3-M8 objects in Cha I does not depend on stellar mass. Diskless and disk-bearing objects have similar spatial distributions. There are no obvious transition disks in our sample, implying a rapid timescale for the inner disk clearing process; however, we find two objects with weak excess at 3-8 microns and substantial excess at 24 microns, which may indicate grain growth and dust settling in the inner disk. For a sub-sample of 35 objects with high-resolution spectra, we investigate the connection between accretion signatures and dusty disks: in the vast majority of cases (29/35) the two are well correlated, suggesting that, on average, the timescale for gas dissipation is similar to that for clearing the inner dust disk. The exceptions are six objects for which dust disks appear to persist even though accretion has ceased or dropped below measurable levels. Adaptive optics images of 65 of our targets reveal that 17 have companions at (projected) separations of 10-80 AU. Of the five <20 AU binaries, four lack infrared excess, possibly indicating that a close companion leads to faster disk dispersal. The closest binary with excess is separated by ~20 AU, which sets an upper limit of ~8 AU for the outer disk radius. (abridged)Comment: accepted for publication in the Astrophysical Journa

Investigation of particles size effects in Dissipative Particle Dynamics (DPD) modelling of colloidal suspensions

In the Dissipative Particle Dynamics (DPD) simulation of suspension, the fluid (solvent) and colloidal particles are replaced by a set of DPD particles and therefore their relative sizes (as measured by their exclusion zones) can affect the maximal packing fraction of the colloidal particles. In this study, we investigate roles of the conservative, dissipative and random forces in this relative size ratio (colloidal/solvent). We propose a mechanism of adjusting the DPD parameters to properly model the solvent phase (the solvent here is supposed to have the same isothermal compressibility to that of water)

High Efficiency Water Splitting using Ultrasound Coupled to a BaTiO 3 Nanofluid

To date, a number of studies have reported the use of vibrations coupled to ferroelectric materials for water splitting. However, producing a stable particle suspension for high efficiency and long-term stability remains a challenge. Here, the first report of the production of a nanofluidic BaTiO3 suspension containing a mixture of cubic and tetragonal phases that splits water under ultrasound is provided. The BaTiO3 particle size reduces from approximately 400 nm to approximately 150 nm during the application of ultrasound and the fine-scale nature of the particulates leads to the formation of a stable nanofluid consisting of BaTiO3 particles suspended as a nanofluid. Long-term testing demonstrates repeatable H2 evolution over 4 days with a continuous 24 h period of stable catalysis. A maximum rate of H2 evolution is found to be 270 mmol h–1 g–1 for a loading of 5 mg l–1 of BaTiO3 in 10% MeOH/H2O. This work indicates the potential of harnessing vibrations for water splitting in functional materials and is the first demonstration of exploiting a ferroelectric nanofluid for stable water splitting, which leads to the highest efficiency of piezoelectrically driven water splitting reported to date