The helix-to-coil denaturation transition in DNA has been investigated in mixed solvents at high concentration using ultraviolet light absorption spectroscopy and small-angle neutron scattering. Two solvents have been used: water and ethylene glycol. The "melting" transition temperature was found to be 94 degrees C for 4% mass fraction DNA/d-water and 38 degrees C for 4% mass fraction DNA/d-eth...

Poly (ether-block-amide) /poly (ethylene glycol)/ carbon nanotubes mixed matrix membranes have been successfully fabricated using solvent evaporation method to determine the effect of ethylene oxide groups on the performance of produced membranes. The effects of CNTs (2-8 wt%) and PEG (up to 50 wt%)were investigated in both single and mixed gas test setup in different temperature and pressure. ...

Mixed solutions of konjac glucomannan supplemented with xanthan and alginate were studied using the technique of sedimentation velocity in the analytical ultracentrifuge. Interactions – as manifested by changes in the sedimentation coefficient distributions compared to unmixed controls – were observed for ternary mixtures in the presence of alginate. The complexes observed also appeared sensiti...

the equilibrium constant of adduct formation between some triorganotin chloride of the type r3sncl (r=c6h5, p-ch3c6h4, n-ch3)ch2)3, c6h5-ch2 and lewis bases cl¯, br¯, and i¯, were measured in 50% v/v ethanol-water solvent spectrophotometrically. the average equilibrium constant values for the systems studied shows the following acceptor trend of tin(iv) in the triorganotin chlorides: p-tolyl > ...

A novel current reference with low temperature and supply sensitivity and without any external component has been developed in a 0.25 m mixed-mode process. The circuit is based on a bandgap reference (BGR) voltage and a CMOS circuit similar to a beta multiplier. An NMOS transistor in triode region has been used in place of a resistor in conventional beta multiplier to achieve a current which ha...

To investigate the effects of implicit solvents on peptide structure and dynamics, we performed extensive molecular dynamics simulations on the penta-peptide Cys-Ala-Gly-Gln-Trp. Two different implicit solvent models based on the CHARMM22 all-atom force field were used. Structural properties of the peptide such as distributions of end-to-end distances and dihedral angles obtained from molecular...

A theoretical analysis is performed to study the flow and heat transfer characteristics of magnetohydrodynamic mixed convection flow of a micropolar fluid past a stretching surface with slip velocity at the surface and heat generation absorption . The transformed equations solved numerically using the Chebyshev spectral method. Numerical results for the velocity, the angular velocity, and the t...

A generalized analytical solution to the set of coupled energy balance equations governing heat transfer in a system comprised of uniform radius spherical particles, with nonuniform initial temperature, heated in a well mixed liquid with time varying temperature, is initially derived. Based on this solution, analytical equations describing the temperature evolution for both fluid and particles,...

Nanotubes composed of C60 molecules (C60NTs) were prepared at ambient pressure and temperature by liquidliquid interfacial precipitation (LLIP) method using pyridine and isopropyl alcohol (IPA) for the solvent of C60 powder. The pyridine solution saturated with C60 was (a) exposed to UV (302 nm) and visible (436 nm) light, (b) mixed with IPA at 1:10, 1:9, 1:8, and 1:7 (C60pyridine:IPA) ratios, ...

In this study, the diffusivity and volumetric mass transfer coefficients for the extraction of β-carotene from crude palm oil using CO2 solvent in supercritical fluid were determined in the pressure range of 7.5-17.5 MPa and temperature range of 80-120 ºC. For this purpose, a statistical method was applied in order to minimize the number of experiments required. The volumetric ma...