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Adulticides applied against mosquitoes can reduce vector populations during times of high arbovirus transmission. However, impacts of these insecticides on pollinators and other non-target organisms are of concern to mosquito control professionals, beekeepers and others. We evaluated mortality of Culex quinquefasciatus and Apis mellifera when caged insects were exposed to low and high label rates of four common adulticides (Aqua-Pursuit™ [permethrin], Duet® [prallethrin + sumithrin], Fyfanon® [malathion] and Scourge® [resmethrin]) at six distances up to 91.4 m from a truck-mounted ultra-low-volume sprayer. Honey bee mortality was both absolutely low (61 m had limited impacts on honey bee mortality while providing effective mosquito control.

Reciprocating magnetic separators are used in the purification of kaolin clay and titanium dioxide. Design parameters and fabrication details are reported for the high temperature superconducting (HTS) coil. The HTS coil is 0.7 m in length and has a 0.5 m inner diameter. The central operating magnetic field is a nominal 3.0 T with a design operating current of 100 A. In terms of combined size and magnetic field strength, this is one of the largest HTS magnets ever fabricated, possessing a stored energy > 0.400 MJ. The HTS magnet is conduction cooled via single-stage G-M cryocoolers with a nominal operating temperature of 30 K. The HTS conductor uses a stainless steel reinforced Bi-2223 material. Salient features and results of the electromagnetic and thermal analyses are discussed.

The test results of a conduction-cooled High Temperature Superconducting (HTS) Reciprocating Magnetic Separator are reported. Reciprocating magnetic separators are used in the purification of kaolin clay. The HTS coil is 0.3 m in length and has a 0.25 m (cold) bore inner diameter. The central operating magnetic field is a nominal 3.0 T with a design operating current of 126 A. In terms of combined size and magnetic field strength, this is one of the largest HTS magnets ever fabricated, possessing a stored energy >0.1 MJ. The HTS magnet is conduction cooled via one single-stage G-M cryocooler with a nominal operating temperature of 30 K. The HTS conductor uses a stainless steel reinforced Bi-2223 material. Salient design features and test results of the HTS magnetic separator are discussed.

The conceptual design and fabrication details of a conduction-cooled high temperature superconducting (HTS) reciprocating magnetic separator are reported. Reciprocating magnetic separators are used in the purification of kaolin clay. The HTS coil is 0.30 m in length and has a 0.25 m inner diameter. The central operating magnetic field is a nominal 3.0 T with a design operating current of 126 A. In terms of combined size and magnetic field strength, this is one of the largest HTS magnets ever fabricated, possessing a stored energy >0.1 MJ. The HTS magnet is conduction cooled via one single-stage G-M cryocooler with a nominal operating temperature of 30 K. The HTS conductor uses a stainless steel reinforced Bi-2223 material. Salient features and results of the electromagnetic, thermal, and quench protection analyses are discussed.

An International Team consisting of DuPont Superconductivity, Oak Ridge National Lab, the Advanced Space Propulsion Laboratory, and Sumitomo Electric Industries, Ltd. has designed and fabricated a conduction-cooled High Temperature Superconducting (HTS) coil for use in the Variable Specific Impulse Magnetoplasma Rocket (VASIMR). The HTS coil will be installed and tested in the ongoing VASIMR experiment at the Advanced Space Propulsion Laboratory at the Johnson Space Center in Houston, TX. The HTS coil is 0.04 m in length, with a 0.23 m inner diameter, and has a mass less than 5.0 kg. The central operating magnetic field is a nominal 0.28 T with a design operating current of /spl sim/105 A. The HTS coil is conduction cooled with a nominal operating temperature of 40 K. The HTS conductor uses a Bi-2223 material with a stainless steel backing strip for reinforcement. Details and test results of the mechanical, thermal, and electromagnetic analyses are discussed.

The conditions for radio waves to propagate through the ionosphere exactly parallel or exactly transverse to the local direction of the centred-dipole-magnetic field are determined. The analysis is based on an appropriate form of the Haselgrove equations for ray-tracing in an inhomogeneous anisotropic medium, and the general forms of the refractive indices required for the persistence of purely longitudinal and purely transverse propagation are determined by integration of the Haselgrove equations. The resultant refractive indices do not appear to be appropriate to the ionosphere.

Certain statistical theories and techniques are described which appear to possess a good deal of potential value for radio propagation research. These include the Kolmogorov-Smimov statistics for testing goodness of fit, the statistical theory of extreme values, and the compound Poisson distribution and certain related stochastic processes. The Kolmogorov-Smimov statistics are defined and their uses described. The relations among per-cent-of-time distribution of signal level, the χ2 test, and the Kolmogorov-Smimov tests are defined and explored. The use of the theory of extreme values in radio propagation research is discussed. The significant probabilistic and statistical aspects of the Poisson distribution are summarized, and the occurrence of Poisson statistics in radio propagation phenomena is briefly described. The application of the compound Poisson process and the additive Gaussian process to the phenomena of fading and meteor burst propagation is discussed.

AN apparently new type of extremely low frequency (e.l.f.) wave motion of the magnetic field in an inhomogeneous hydromagnetic medium flowing about a conducting magnetized sphere is shown to exist under certain conditions upon the flow velocity, the conductivity, and their respective divergence and gradient. Satellite magnetometer data and the characteristics of geomagnetic micropulsations are discussed in relation to this theoretical model.