1,429 research outputs found
Economically viable domestic roofwater harvesting
Economically viable domestic roofwater harvestin
Better, faster, cheaper: research into roofwater harvesting for water supply in low income countries
Risk Assessment of Grape Berry Moth and Guidelines for Management of the Eastern Grape Leafhopper
Several factors have prompted the reevaluation of control
recommendations for key pests of grapes in recent years.
First, the costs of insecticides and their application have risen
substantially. Growers who improve the efficiency of their
use of pesticides can realize significant savings in production
costs. Second, grape processors have responded to consumer
desires to minimize pesticide residues in food by promoting
judicious use of pesticides. Finally, increased governmental
restrictions regarding what pesticides can be used in vineyards
and how they may be used may increase the overall
difficulty that growers encounter when using pesticides. The
result of these factors is that while producers and processors
continue to require control of economically-damaging pests,
this now must be achieved with the least amount of pesticide
possible. The Grape Berry Moth Risk Assessment Program
was developed to address these concerns. In this publication
we describe how Risk Assessment can be used to maintain
acceptable control of grape berry moth and the Eastern grape
leafhopper while minimizing use of insecticides
Superconducting-coil--resistor circuit with electric field quadratic in the current
It is shown for the first time that the observed [Phys. Lett. A 162 (1992)
105] potential difference Phi_t between the resistor and the screen surrounding
the circuit is caused by polarization of the resistor because of the kinetic
energy of the electrons of the superconducting coil. The proportionality of
Phi_t to the square of the current and to the length of the superconducting
wire is explained. It is pointed out that measuring Phi_t makes it possible to
determine the Fermi quasimomentum of the electrons of a metal resistor.Comment: 2 pages, 1 figur
Formation of MnI lines in the solar atmosphere
We present a detailed NLTE analysis of 39 MnI lines in the solar spectrum.
The influence of NLTE effects on the line formation and element abundance is
investigated. Our goal is the derivation of solar log gfe values for manganese
lines, which will later be used in differential abundance analysis of
metal-poor stars. The method of spectrum synthesis is employed, which is based
on a solar model atmosphere with initially specified element abundances. A
manganese abundance of 5.47 dex is used with the theoretical line-blanketed
model atmosphere. Statistical equilibrium calculations are carried out for the
model atom, which comprises 245 and 213 levels for MnI and MnII, respectively.
Photoionization cross-sections are assumed hydrogenic. For line synthesis van
der Waals broadening is calculated according to Anstee & O'Mara's formalism. It
is shown that hyperfine structure of the Mn lines also has strong broadening
effects, and that manganese is prone to NLTE effects in the solar atmosphere.
The nature of the NLTE effects and the validity of the LTE approach are
discussed in detail. The role of photoionization and collisional interaction is
investigated.Comment: 17 pages, 27 figures, accepted for publication in A&
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