Effect of Microwave Irradiation on Xylanase Production from Wheat Bran and Biobleaching of Eucalyptus Kraft Pulp

Microwave irradiation (MWI) was used as pretreatment of wheat bran and eucalyptus kraft pulp to examine its effect on xylanase production by Bacillus halodurans FNP 135 using solid state fermentation and biobleaching with xylanase, respectively. Irradiation of wheat bran under optimized conditions (600?W, 6?min, and 20?% consistency) resulted in 56.8, and 31.7?% increase in xylanase yield and water absorbance of wheat bran and 17.3?% reduction in reducing sugars content. Optimized MWI of kraft pulp at 850?W, 2?min, and 20?% consistency led to 0.9?% increase in brightness, 10?% decrease in kappa number, 7.7?% increase in water absorbance, 4.6?% decrease in tear factor, 0.9?% increase in burst factor, and 7.5?% increase in viscosity. Also, MWI enhanced xylanase-mediated biobleaching by increasing brightness (1.1?%) and decreasing kappa number (14.3?%) and leading to a total of about 20?% reduction in chlorine consumption. MWI is an economical, efficient, and environment-friendly pretreatment of wheat bran and pulp for enhanced enzyme yield and rapid heating, respectively.     

XPS and SIMS characterisation of TiOxNy solar absorber films

Solar thermal collectors have been prepared with thin TiO_xN_y films deposited using ion beam assisted deposition, on Si and Cu substrates. The films are amorphous and x and y were controlled by altering the O₂/N₂ ratio in the gas source. After annealing at temperatures of 200 – 400 °C, films have been depth profiled using Secondary Ion Mass Spectrometry. Profiles reveal the degradation of the film, particularly for films on Cu substrates, by migration of the substrate atoms through the films, to the sample surface. In general, films with x<1 and y>1 show improved temperature stability, ultimately at the expense of a reduced transmission window. Contrary to previous suggestions in the literature, the degradation mechanism initially involves the formation of a nitrogen rich phase, rather than an oxide at the film surface. On copper substrates, the nature of the films and of this phase, formed by diffusion of the substrate atoms, have been investigated by X-ray photoelectron spectroscopy (XPS). These investigations reveal complex behaviour in the early stages of film failure, with the suggestion that the initial films, at least near the surface, are two phase, and the reaction layer mixes the TiO_xN_y with some Ti replacement by ions from the Cu substrate.     

A combined harmonic phase and strain-encoded pulse sequence for measuring three-dimensional strain

Measurement of myocardial strain provides direct information about heart function that can be correlated with disease. We present an MRI pulse sequence that acquires in just six heartbeats both harmonic phase (HARP) and strain-encoded (SENC) images and provides dense measurements of radial, circumferential and longitudinal strains within a single short-axis slice. Normal volunteer data confirm the feasibility of this pulse sequence, and acquired data demonstrate the strain measurement reliability.     

The geodesic spray,the vertical projection,and Raychaudhuri's equation

The metric connection on a space-time manifoldM defines on its tangent bundleTM a distribution of subspaces complementary to the vertical subspaces and therefore called horizontal. We give a formula for the Lie derivative with respect to the geodesic spray of the tensor field onTM which defines projection onto the vertical subspace along the horizontal subspace; and we show that this formula is a universal version of the equation, for a geodesic local vector field onM, whose trace is Raychaudhuri's equation.     

Projective differential geometry and geodesic conservation laws in general relativity,II: Conservation laws

We examine the geodesic conservation laws associated with the projective actions discussed in our earlier paper with the same overall title. Using the Cartan formalism, a one-to-one correspondence between a class of these actions and all geodesic conservation laws is possible. In particular there is a natural geometric interpretation of Killing tensors. Homothetic motions are shown to correspond to conserved quantities on all geodesies (not just null ones). The same approach identifies homothetic Killing tensors and a universal quadratic first integral which reduces to the conformai Killing tensor case on null geodesics.     

The translation planes of order 81 that admit SL(2,5), generated by affine elations

The translation planes of order 81 admitting SL(2, 5), generated by affine elations, are completely determined. There are seven mutually non-isomorphic translation planes, of which five are new. Each of these planes may be derived producing another set of seven mutually non-isomorphic translation planes admitting SL(2, 5), where the 3-elements are Baer. Of this latter set, five planes are new.