The objective of this study was to investigate the moisture removal characteristics of thin layer rough rice heated by infrared (IR) and cooled with various cooling methods. Thin layer rough rice samples with different initial moisture contents (MCs) were heated using a catalytic IR emitter for four exposure times and radiation intensities. High heating rate and moisture removal were achieved during the IR heating period. After heating, more moisture removal was achieved during the cooling period. The achieved grain temperatures ranged from 35.1 to 68.4C under the tested heating conditions. The vacuum and forced air cooling methods removed more moisture than did the natural cooling. When rice with 25.7% MC was heated by IR, MC was reduced by 3.2, 3.5, and 3.8 percentage points for rice heated to 63.5C at the IR intensity of 5348 W/m2 for120 s followed by natural cooling for 40 min, forced air cooling for 5 min and vacuum cooling for 10 min, respectively. Practical Applications To design efficient infrared (IR) dryers for rough rice, it is important to optimize the operating parameters of IR dryer to achieve high heating rate, fast drying and good quality of end‐products. To achieve the aforementioned objectives, we have been conducting several studies including our previous publications (Pan, Khir et al. and this study). The outcomes of our studies have clearly indicated that a high heating rate, fast drying, good quality and simultaneous drying and disinfestation can be achieved by IR heating of rough rice to bout 60C followed by tempering and natural cooling with tested bed thickness up to 10 mm. Consequently, IR heating followed by cooling could be an effective approach for designing IR rough rice dryers. It is expected that this alternative approach could be used as an energy saving drying method with improved drying efficiency, space saving, clean working environment and superior product quality compared with the conventional heated air drying method.

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This study was carried out to evaluate some aerodynamic properties of some oilseeds (peanut kernels, soybean and cotton seeds) under different moisture conditions. Peanut kernels were conditioned to moisture contents of 6.1, 9.3, 16.0, 28.4 and 34.9% (w.b.), soybean seeds to 7.8, 14.4, 21.0, 26.0 and 31.8% (w.b.) and cotton seeds to 6.4, 8.6, 10.8 and 12.5% (w.b.). Aerodynamic properties such as terminal velocity, Reynold's number and drag coefficient were determined for all tested seeds as a function of moisture content. The results revealed that the measured aerodynamic properties are significantly affected by moisture contents for the three tested oil crops. When the moisture content increased the terminal velocity and Reynold's number increased for all investigated seeds. However, the drag coefficient did not show a consistent trend with moisture content increment for peanut kernels and soybean seeds. While, it decreased for cotton seeds with moisture content increment.

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The red-striped soft scale insect, Pulvinaria tenuivalvata (Newstead) (Hemiptera : Coccidae) is a serious pest on sugarcane. As a basic study for developing future management of this scale species, seasonal activity of different stages of this insect was carried out through two successive seasons (2006/2007 and 2007/2008) at Esna district, Qena governorate. The obtained results showed that, P. tenuivalvata had four peaks occurred in mid of July, mid-September, beginning of November and beginning of December per season. The second season of study cleared that the total population of this insect was higher in comparison to the first season of investigation, which may due to the influence of favourable factors. The combined effect of the tested weather factors was responsible about some in the total population. The percentages of explained variance (E.V.) indicate that all tested variables were together responsible for (30.6 and 42%) during the two seasons of study, respectively.