Preliminary investigation of fungal bioprocessing of wheat straw for production of straw-thermoplastic composites

Straw utilization for composites is limited by poor resin and polymer penetration, and excessive resin consumption owing to the straw cuticle, fines, and lignin-hemicellulose matrix. White-rot fungi degrade these components of straw and could, therefore, potentially be used to improve resin penetration and resin binding without the use of physical or chemical pretreatments. Although long treatment times and large footprints the limit use of fungal treatments on a large scale, distributed fungal pretreatments could alleviate land requirements. In this article, we present progress toward the development of a passive fungal straw upgrading system utilizing whiterot fungi.     

The inverse problem of the calculus of variations: The use of geometrical calculus in Douglas's analysis

The main objective of this paper is to work out a full-scale application of the integrability analysis of the inverse problem of the calculus of variations, as developed in recent papers by Sarlet and Crampin. For this purpose, the celebrated work of Douglas on systems with two degrees of freedom is taken as the reference model. It is shown that the coordinate-free, geometrical calculus used in Sarlet and Crampin's general theoretical developments provides effective tools also to do the practical calculations. The result is not only that all subcases distinguished by Douglas can be given a more intrinsic characterization, but also that in most of the cases, the calculations can be carried out in a more efficient way and often lead to sharper conclusions.

     

The effect of double heterojunction waveguide parameters on the far field emission patterns of lasers

A model of double-heterostructure lasers is developed which gives the far-field pattern of the laser in terms of such waveguide parameters as the active region width and the dielectric constants of the layers forming the waveguide. For symmetrical waveguides an explicit expression is given. Experimental results are presented which show a close agreement between the theory and the measured far-field patterns. By adding an extra passive layer to the conventional double heterostructure laser a structure is produced in which the measured half-power width of the far-field distribution is reduced from 55° to 32°. It is shown in this case that the model is useful for estimating the near-field pattern from the measured far-field pattern and hence determining the unknown waveguide parameters.     

Effects of imaginary potentials on spurious resonances in resonating-group calculations

By studying the coupled-channel d + ³He and p + α resonating-group calculation, it is found that the introduction of phenomenological imaginary potentials is a simple way to eliminate spurious resonances from resonating-group and perhaps other microscopic reaction calculations.     

Competing Ising interactions and chaotic glass-like behaviour on a Cayley tree

For the Ising model on a Cayley tree with competing nearest neighbour coupling J and next nearest neighbour coupling J′, we find in addition to the expected paramagnetic, ferromagnetic and antiferromagnetic phases, an intermediate range of J′/J < 0 values where the local magnetization has chaotic oscillatory glass-like behaviour.     

Inclusive K10(890) production in π−p interactions at 16 GeV/c

Inclusive $\text{K}{}^{10}$ production is studied in π^?p interactions at 16 GeV/c with x_? > 0.2. The $\text{K}{}^{10}$ is found to be pre-dominantly centrally produced with cross section $\text{σ(}\text{K}{}^{10}\text{) = (72 ± 12) μb}$ for x_? > 0.2 and compares closely to data on $\text{K}{}^{10}$ production in π⁺p interactions at the same energy.     

Observations on lifetimes and excitation processes for the upper states in atomic helium

Lifetime observations have been made on 49 energy levels of helium. Good overall agreement with theory is obtained, with significant exceptions, the most striking of which are the 3¹D and 3³D states, where 50% discrepancies with theory and some of the older measurements are found. The new measurements are, however, in harmony with recent results using the Hanle effect.The existence of the upper-state transfer process is clearly delineated by the results for n > 6.