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A Bohr-like model of the planetary system and its gravitoelectric characteristics
No full textWe have presented a quantum model of planetary system analogous to Bohr model of
hydrogen atom. The quantization of the angular momentum of planets agrees with Newtonian
calculations. We also derive the energy density and power delivered by the system employing
the electro-gravity analogy
Investigations of environmental radioactivity in the northern state of Sudan
No full textInvestigations have been carried out for naturally occurring radionuclides in surface soils in selected regions of the Northern State of Sudan, in response to widely spread rumours of elevated levels of radioactivity causing higher than normal incidence of cancer in that area. Eighty surface soil samples were collected from different regions in the Northern State and their activity concentrations were measured by a high-purity germanium detector gamma spectrometer system. From the data obtained the mean values and standard deviations of the radionuclide activities were calculated. From the activity concentrations of 226Ra, 232Th and 40K radionuclides the external absorbed dose rate in air and the annual effective dose were calculated. The radium equivalent activity and the external hazard index were applied for estimating the radiation hazards of soil used as building material. The mean activity concentrations of 226Ra, 232Th and 40K in different regions of the Northern State were found to be 82.6 + 6.8, 26.0 + 2.9 and 726.4 + 72.0 Bq/kg, respectively. The average outdoor gamma absorbed dose rate in air at 1meter above ground was calculated as 84.6 + 7.1 nGy/h. The average annual effective dose equivalent for population in the regions under study was found to be 103.7 + 8.7 uSv/y. The external hazard index was found to be 0.48 + 0.04
Water chemistry and quality of the Blue Nile at Khartoum
No full textMeasurements of physical and chemical variables were made fortnightly on the Blue Nile near Khartoum, from May 2000 to February 2002. The variables analysed were: temperature, pH, and concentrations of total residue, dissolved oxygen, alkalinity, phosphate-phosphorus, nitrate-nitrogen, silica-silicon, calcium, magnesium, sodium, potassium, and oxidizable organic matter. The seasonal variations of these factors in the Blue Nile are compared, and the interrelationships existing between some of them are discussed. Comparisons are made with earlier studies carried out on the same site in the Blue Nile and with some tropical rivers. In the Blue Nile, the amounts of suspended matter and nutrients are largely dependent upon the flood regime. Nitrate, phosphate, silicate, oxidizable organic matter and total residue increase considerably in the Blue Nile when the river is in flood. Silicate-silicon as silica was reduced at certain times of the year, yet the relatively high concentrations, which were maintained throughout the year, were not expected to limit the growth of diatoms. Drops in silicon concentrations, unlike those in nitrate and phosphate, were always followed by a rapid restoration of a higher level. Compared with pre 1970 data, the Blue Nile at Khartoum did not show any sign of unwelcome enrichment. The river at Khartoum is far from being polluted by heavy metals; no cadmium, lead, or nickel was detected in the surface waters
Government Expenditure and Economic Development: a case study of the Sudan
No full textKhartoum: u.of k. publishe
Study of attractiveness and palatability of the German cockroaches, Blattella germanica (L) to Peanut butter baits under laboratory conditions
No full textThis research has been conducted at the laboratory of Dubai Public Health Pest Control Section / Dubai Municipality. The project consists of two parts: The first part concerns the evaluation of attractivity and palatability of the German cockroach Blattella germanica to peanut butter baits under the laboratory conditions. The sources of this butter were Sudan, India, China, USA and Ethiopia. The apparatus used in these experiments was a five-chambered choice chamber denoted as the New Pentadevice Arena (60 cm in diameter). One fine strip of each food was placed in each chamber. Fifty insects of different stages of development were placed at the center of the arena. Number of insects in each chamber was counted after ten minutes. The Sudanese peanut butter food (PNB4) showed the highest record of numbers of insects. A third method was adopted to confirm these results– namely biting effects
اثار السيول دراسة حالة امبدة الحارة (15)
No full textاثار السيول دراسة حالة امبدة الحارة (15)اثار السيول دراسة حالة امبدة الحارة (15
السياحة النيليةمن كبرى المنشية وحتى مقرن النيلين
No full textالسياحة النيلية من كبرى المنشية وحتى مقرن النيلي
المحاصيل النقدية بولاية نهر النيل ومحصول البصل بصفة خاصة
No full textالمحاصيل النقدية بولاية نهر النيل ومحصول البصل بصفة خاص