1,280 research outputs found
The eradication of insect pests - Some observations on the Argentine Ant campaign in Western Australia
To an entomologist, and especially an economic entomologist, the word eradication means the destruction of all members of a species of insect in any particular area. It means the perfection of a project in the control of an economic insect pest.
Adapted from an address given before the Australian Institute of Agricultural Science (West Australian Branch), by the Retiring President (Mr. P. N. Forte, B.Sc, Agric.) on April 13, 1956
The control of mealy bug on vines in Western Australia
The mealy bug (Pseudococcus maritimus Ehr.) was first recorded on vines in Western Australia in 1898 (A. M. Lea, 1898). Since then it has been reported present in certain years in large numbers with consequent loss of quality in the vine products
Winter pests in the pasture
ALTHOUGH the pests concerned in attacking winter pastures are known to most farmers a discussion of their control and relative importance will not be out of place.
The principal pests concerned fall into two groups. Firstly the red-legged earth mite and lucerne flea whose attacks are most noticeable soon after germination and secondly a group of caterpillars which appear about the same time and whose attack is not noticed until a large amount of damage has been done
The effectiveness of dieldrin for control of the Argentine ant in Western Australia
The results of three experiments to compare insecticides for the eradication of Argentine ants are reported. The areas used for the tests were typical household allotments in Shenton Park, a suburb of Perth, Western Australia. The methods of application of sprays and evaluation of results were the same as described in a previous paper. (Forte & Greaves 1953.
New insecticides for the control of the Argentine ant in Western Australia
The Argentine Ant (Iridomyrmex humilis Mayr), has been the subject of much investigation in Western Australia. Jenkins (1943), Jenkins and Forte (1946, 1951), Jenkins (1948) and Forte (1949) have reported results of extensive work on the control of this pest. The results of the investigations have shown that effective control can be obtained by the use of DDT sprays but that large scale eradication was not possible with DDT
Control of Prodenia litura on cotton in the north of Western Australia
COTTON is subject to considerable insect attack at the new Ord River irrigation area in the East Kimberleys of Western Australia.
Although a long list of insects have been recorded as damaging cotton in this area there are two which have proved so far to present the biggest problem.
These are Heliothis punctigera and Prodenia litura
Anomaly-Induced Magnetic Screening in 2+1 dimensional QED at Finite Density
We show that in 2+1 dimensional Quantum Electrodynamics an external magnetic
field applied to a finite density of massless fermions is screened, due to a
-dimensional realization of the underlying -dimensional axial anomaly
of the space components of the electric current. This is shown to imply
screening of the magnetic field, i.e., the Meissner effect. We discuss the
physical implications of this result.Comment: 8 pages, DFTT-93-10 [ Eq.(15) and (16) were scrambled in previous
version
Chemicals for Argentine ant control
The Argentine ant is one of the most serious ant pests in the world and as such, has been the subject of large-scale control campaigns in several countries.
Early control measures against the Argentine ant in Western Australia involved quarantine of infected areas and the use of arsenical baits, based mainly on the so-called U.S. Government formula.
Since this time the hunt has been on for a more effective chemical, without undesirable effects
Nonlinear damage analysis: Postulate and evaluation
The objective of this program is to assess the viability of a damage postulate which asserts that the fatigue resistance curve of a metal is history dependent due to inelastic action. The study focusses on OFE copper because this simple model material accentuates the inelastic action central to the damage postulate. Data relevant to damage evolution and crack initiation are developed via a study of surface topography. The effects of surface layer residual stresses are explored via comparative testing as were the effects in initial prestraining. The results of the study very clearly show the deformation history dependence of the fatigue resistance of OFE copper. Furthermore the concept of deformation history dependence is shown to qualitatively explain the fatigue resistance of all histories considered. Likewise quantitative predictions for block cycle histories are found to accurately track the observed results. In this respect the assertion that damage per cycle for a given level of the damage parameter is deformation history dependent appears to be physically justified
Multiphysics Optimization for First Wall Design Enhancement in Water-Cooled Breeding Blankets
The commercial feasibility of the first fusion power plant generation adopting D-T plasma is strongly dependent upon the self-sustainability in terms of tritium fuelling. Within such a kind of reactor, the component selected to house the tritium breeding reactions is the breeding blanket, which is further assigned to heat power removal and radiation shielding functions. As a consequence of both its role and position, the breeding blanket is heavily exposed to both surface and volumetric heat loads and, hence, its design requires a typical multiphysics approach, from the neutronics to the thermo-mechanics. During last years, a great deal of effort has been put in the optimization of the breeding blanket design, with the aim of maximizing the tritium breeding and heat removal performances without undermining its structural integrity. In this paper, a derivative-free optimization method named “Complex method” is applied for the design optimization of the European DEMO Water-Cooled Lithium Lead breeding blanket concept. To this purpose, a potential performances-based objective function, focusing on the maximization of the tritium breeding, is defined and a multiphysics numerical model of the blanket is developed in order to solve the coupled thermo-mechanical problem, while the optimization algorithm leads the design towards a minimum optimum point compliant with the prescribed requirements. Once the optimized design is obtained, its nuclear and thermo-structural performances are assessed by means of specific neutron transport and multiphysics simulations, respectively. Finally, the structural integrity is verified by means of the application of the RCC-MRx design criteria
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