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Deals with a study which investigated the effects of flowers distribution, tree shape, charging levels and airflow characteristics on the amount of pollen deposited artificially by an electrostatic pollinator on various tree parts. Methods and materials; Effect of branch depth on the amount of pollen deposited; Improvement in fruit set of almonds due to artificial pollination with and without electrostatic charging.

The effects of five economically important vegetable (seed) oils, peanut, cottonseed, castor, soybean and sunflower, on adult and immature stages of the sweetpotato whitefly(Bemisia tabaci(Gennadius) [Hemiptera: Aleyrodidae]) were studied in the laboratory. Irrespective of origin, oil residues had similar effects on immature stages and adult mortality, and on settling and oviposition deterrence. Trends for 5-h settling, 24-h oviposition and 24-h survival of adults on treated plants were similar for oils applied at the same concentration range. Settling deterrence was strong enough to cause adult death due to starvation or dehydration under no-choice conditions, and caused greater mortality than direct physical toxicity; similar results were obtained when adult survival on oil residues was compared to survival of starved adults. Adults recovered when transferred from oil-treated to untreated plants. All oils produced similar effects when sprayed on immatures; the egg and fourth instar (pupa) were the most tolerant stages. The oil concentration required for significant effects on whitefly mortality and behavior was relatively high (>0.3%) compared with published efficacy data for synthetic pesticides, and varied to some extent with oil origin. All tested oils were active as direct and residual larvicides. Peanut oil was the most effective for all tested effects, followed by cottonseed oil, which was significantly less effective than peanut and castor oils when applied-directly to eggs. Only by this latter parameter was castor oil more effective than cottonseed oil and similar to peanut oil. As direct sprays to larvae, soybean and sunflower oils resembled castor oils, but their residues were less effective against all stages.

This paper reviews research on the role of electrostatic forces in pollination, both in natural and in agricultural systems. Researchers from various fields of biological studies have reported phenomena which they related to electrostatic forces. The theory of electrostatically mediated pollen transfer between insect pollinators and the flowers they visit is described, including recent studies which confirmed that the accumulated charges on airborne honey bees are sufficient for non-contact pollen detachment by electrostatic forces (i.e., electrostatic pollination). The most important morphological features in flower adaptiveness to electrostatic pollination were determined by means of two theoretical models of a flower exposed to an approaching charged cloud of pollen; they are style length and flower opening. Supplementary pollination by using electrostatic techniques is reported, and its possible importance in modern agriculture is discussed.

The problem of a viscoelastic agricultural product colliding with an elastic plate was investigated analytically and the results were verified experimentally, in order to optimize the separation of hard objects from soft ones. Two rheological models developed in the past, one for a collision of an elastic sphere with an elastic plate, and the second for a collision of a viscoelastic fruit with a rigid flat surface, were combined to form an extended model. The extended model is capable of describing the collision of a viscoelastic agricultural product with an elastic plate. Good agreement was found between its predictions and experimental results. In a particular case, separation of stones from potatoes was required. The impact energy of the stones was absorbed by an elastic plate and consequently its restitution coefficient was reduced. The reduction in the restitution coefficient of the stones was sufficient to enable them to be separated from the potatoes. A design of machine for the separation of soft from hard agricultural products could be based on the developed model, with consideration of the properties of the plate and the products.

Second-generation, 3-micrometer, bipolar, isoplanar integrated- injection logic (I3L), VLSI technology has been used to produce an extremely dense, highly optimized, high-speed, 16-bit, real-time microprocessor, the F9450. Incorporating microcoded architecture to implement floating-point instructions, the F9450, also implements military-standard instruction-set architecture (ISA), MIL-STD-1750A. F9450 is optimized for use in high- speed, high-precision, real-time applications such as is needed in automatic flight control, inertial navigation, and industrial control. Details of the architecture and capabilities of the F9450 are given, including circuit and architectural diagrams.

An ultrasonic testing technique was applied for non-destructive quality evaluation of avocado fruit and quantitative relations were established between ultrasonic parameters and maturity related factors. The fruits of the same batch and picking date softened at different storage times, a phenomenon which was attributed to different biological ages of the fruit at the picking date. Time-shifting of the test results of each fruit according to its firmness reduced the scatter of the experimental data. Second-order polynomial expressions represented well the changes in attenuation of the ultrasonic signals and the firmness of the fruit with storage time. A cubic equation represents fairly well the wave velocity of the ultrasonic signals versus time. A linear relationship was found between attenuation of the ultrasonic signal and firmness as measured in a cone penetrometer test. It was concluded that equations of this type may be used for prediction of ripening and shelf-life of avocado fruit, and could replace the commonly used penetrometer method. Further steps, such as the averaging of repeated measurements, may be needed to reduce scatter when predicting the maturity of individual fruits.

The global trend to shift from highly toxic pesticides to environmentally safe and less toxic chemicals requires, generally, very high spatial uniformity of the spray deposition. Effective penetration of the spray into a dense canopy can be achieved by utilizing fast air-streams. In contrast, slow and turbulent flow near the leaves and the stems is required for good deposition of the spray. A new sprayer was designed to achieve a sharp decline in air velocity to meet the two — seemingly contradictory — constraints, and thereby obtain effective penetration and coverage of dense canopy. In the present work, air ducts with several shapes of air outlets were developed and tested in an attmept to meet these requirements. Generally, a short and wide air slit created a moderate decline in air velocity; a longer and narrower air slit improved the uniformity of the air velocity along the slit outlet, and brought about a sharper decline in speed of the air-streams. Installing air deflectors at the air outlets added a slight upward motion to the air-streams and enhanced spray deposition on the underside of leaves. Preliminary field tests with the long and narrow air slit showed uniform spray deposition on all plant parts.