2,573 research outputs found
The potential for slug control with ferric phosphate
Slug and snail damage, especially on young plants can mean serious economic loss for growers. Organic growers have in the past had few, if any, effective products to use for their control. Now ferric phosphate has recently gained organic status from the Organic Farmers and Growers organisation. Its unique mode of action, environmental profile and effectiveness against a range of slug and snail species will make this a first choice for all organic growers. The eventual breakdown components iron and phosphate, will contribute to the crop’s nutrient supply
The development and potential of the biological insecticide granulovirus on codling moth
Cydia pomonella granulovirus is being developed for the UK market and offers opportunities for orchard growers to develop reduced pesticide residue programmes when targeting codling moth control
Boundary Effects in the One Dimensional Coulomb Gas
We use the functional integral technique of Edwards and Lenard to solve the
statistical mechanics of a one dimensional Coulomb gas with boundary
interactions leading to surface charging. The theory examined is a one
dimensional model for a soap film. Finite size effects and the phenomenon of
charge regulation are studied. We also discuss the pressure of disjunction for
such a film. Even in the absence of boundary potentials we find that the
presence of a surface affects the physics in finite systems. In general we find
that in the presence of a boundary potential the long distance disjoining
pressure is positive but may become negative at closer interplane separations.
This is in accordance with the attractive forces seen at close separations in
colloidal and soap film experiments and with three dimensional calculations
beyond mean field. Finally our exact results are compared with the predictions
of the corresponding Poisson-Boltzmann theory which is often used in the
context of colloidal and thin liquid film systems.Comment: 28 pages, LATEX2e, 11 figures, uses styles[12pt] resubmission because
of minor corrections to tex
S_3 and the L=1 Baryons in the Quark Model and the Chiral Quark Model
The S_3 symmetry corresponding to permuting the positions of the quarks
within a baryon allows us to study the 70-plet of L=1 baryons without an
explicit choice for the spatial part of the quark wave functions: given a set
of operators with definite transformation properties under the spin-flavor
group SU(3) x SU(2) and under this S_3, the masses of the baryons can be
expressed in terms of a small number of unknown parameters which are fit to the
observed L=1 baryon mass spectrum. This approach is applied to study both the
quark model and chiral constituent quark model. The latter theory leads to a
set of mass perturbations which more satisfactorily fits the observed L=1
baryon mass spectrum (though we can say nothing, within our approach, about the
physical reasonableness of the parameters in the fit). Predictions for the
mixing angles and the unobserved baryon masses are given for both models as
well as a discussion of specific baryons.Comment: 24 pages, requires picte
An evaluation of the IDEEA™ activity monitor for estimating energy expenditure
Peer reviewedPublisher PD
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