The design and development of a suspension burner system for particulate forestry and agricultural residues (NRI Bulletin No. 41)

This bulletin details research and development work by the Process Development and Storage Engineering Department of the Natural Resources Institute on combustion of particulate forestry and agricultural wastes in a cyclonic suspension burner with a process heat output of 250-500 MJ/h. An application for burning wood residues was identified and this work led to the successful development of a timber drying system. This sytem has now been tested overseas and is available commercially

Technical evaluation of wood wool/cement slabs made from Pinus caribaea grown in Fiji (L48)

Following a TPI techno-economic feasibility study of wood wool slab manufacture in Fiji a request was received for the following tests to be undertaken as a source of data for local assessments of wood wool/cement slab structural properties: (a) Compressive strength of full-sized slab; (b) Deflection under uniform loading to failure; (c) Failing load of the dowel/wood wool slab joint; (d) Shear strength of full sized slab. These tests, with the exception of shear, were undertaken by TPI in consultation with the Overseas Division of the Building Research Establishment. Shear testing was undertaken by private consultants under BRE(OD) funding. Methods used and results obtained, together with additional tests including the assessment of fire propagation and wetting expansion and drying shrinkage, are given in this report. Also included as Appendix I is a technical assessment of the minimum chemical and other raw material inputs required to produce wood wool/cement slabs to meet British Standards from P. caribaea. Comments were obtained from BRE(OD) and are given in Appendix III

The use of coconut oil/diesel blends as a fuel for compression ignition engines (ODNRI Bulletin No. 31)

This bulletin describes experimental and evaluative work carried out by the Overseas Development Natural Resources Institute (ODNRI) to investigate fuelling of a standard compression ignition engine with blends of coconut oil and diesel. Initial studies were made of fuel-related properties for pure coconut oil and for a full range of blends with diesel. A major upgrading of the standard engine's fuel filtration system was necessary but thereafter it was found that a blend of 80% coconut oil in diesel, when heated to 45°C, provided a technically feasible substitute fuel. A limited duration engine trial was completed with this alternative arrangement to assess maintenance and operational requirements. On the basis of these results a preliminary economic evaluation was made of the potential for wider adoption of this type of substitute fuelling. Whilst this indicated that at prevailing prices of coconut oil relative to diesel this was unattractive, circumstances were identified in which this technology could have potential application

Bernstein modes in a weakly relativistic electron-positron plasma

The kinetic theory of weakly relativistic electron-positron plasmas, producing dispersion relations for the electrostatic Bernstein modes was addressed. The treatment presented preserves the full momentum dependence of the cyclotron frequency, albeit with a relaxation on the true relativistic form of the distribution function. The implications of this new treatment were confined largely to astrophysical plasmas, where relativistic electronpositron plasmas occur naturally

Uptake of smoking cessation aids by smokers with a mental illness

Psychiatric inpatient settings represent an opportunity to initiate the provision of tobacco cessation care to smokers with a mental illness. This study describes the use of evidence-based smoking cessation aids proactively and universally offered to a population of psychiatric inpatients upon discharge, and explores factors associated with their uptake. Data derived from the conduct of a randomised controlled trial were analysed in terms of the proportion of participants (N = 378) that utilised cessation aids including project delivered telephone smoking cessation counselling and nicotine replacement therapy (NRT), and Quitline support. Factors associated with uptake of cessation aids were explored using multivariable logistic regression analyses. A large proportion of smokers utilised project delivered cessation counselling calls (89 %) and NRT (79 %), while 11 % used the Quitline. The majority accepted more than seven project delivered telephone cessation counselling calls (52 %), and reported NRT use during more than half of their accepted calls (70 %). Older age, higher nicotine dependence, irregular smoking and seeing oneself as a non-smoker were associated with uptake of behavioural cessation aids. Higher nicotine dependence was similarly associated with use of pharmacological aids, as was NRT use whilst an inpatient. Most smokers with a mental illness took up a proactive offer of aids to support their stopping smoking. Consideration by service providers of factors associated with uptake may increase further the proportion of such smokers who use evidence-based cessation aids and consequently quit smoking successfully

Investigation of High Power Impulse Magnetron Sputtering deposited nanoscale CrN/NbN multilayer coating for tribocorrosion resistance

Recycling equipment (waste/sea water/chemicals) need high tribocorrosion resistance. In this work High Power Impulse Magnetron Sputtering technique deposited nanoscale CrN/NbN multilayer coating for tribocorrosion resistance is explored. Sliding-wear experiments were conducted on CrN/NbN coated High Speed Steel (HSS) test coupons with an alumina (Al2O3) ball as a counterpart in a corrosive environment (3.5% NaCl solution) under potentiodynamic and potentiostatic conditions. Results reveal that coated substrates exhibited (by a factor of 3) lower corrosion currents and high tribo-corrosion resistance (Kc = 2 × 10−15 m3N−1m−1) as compared to uncoated HSS specimens. The alumina counterpart exhibited negligible wear in all the tests. Superior adhesion and dense microstructure consisting of flat and well-defined hard nitride nanolayers leads to stable friction coefficients and retain the unique nanoscale layer-by-layer wear mechanism without delamination. Effect of corrosion on friction coefficients, wear mechanisms and vice versa has been presented

Population dynamics in compressible flows

Organisms often grow, migrate and compete in liquid environments, as well as on solid surfaces. However, relatively little is known about what happens when competing species are mixed and compressed by fluid turbulence. In these lectures we review our recent work on population dynamics and population genetics in compressible velocity fields of one and two dimensions. We discuss why compressible turbulence is relevant for population dynamics in the ocean and we consider cases both where the velocity field is turbulent and when it is static. Furthermore, we investigate populations in terms of a continuos density field and when the populations are treated via discrete particles. In the last case we focus on the competition and fixation of one species compared to anotherComment: 16 pages, talk delivered at the Geilo Winter School 201