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21.
Fouad N. Ibrahim 《GeoJournal》1982,6(1):63-67
This paper gives a brief account of the social and economic situation of the Copts in Egypt. As an ethnic group the Copts are the pure successors of the ancient Egyptians. This does not imply that the Moslems are pure Arabs. At least 90% of the Egyptian Moslems are of Coptic origin, so that no particular differentiation should be made between the Copts and the Moslems of Egypt from the ethnical point of view. The Copts are fully integrated into the Egyptian population. Only in times of religious persecution, they huddled together in villages of Upper Egypt in the provinces of El Minia and Assiut. The recent wave of reislamisation in the Near East has inflicted some suffering on the Copts of Egypt. This was combined with economic losses. Nasser's nationalisation of private concerns and confiscation of large tenures of land was a blow directed against the Copts. Suggestions are made to improve their situation with the aim of giving them equal rigths with the Moslems in the political, social, economic, and religious fields. 相似文献
22.
Desertification involves several morphodynamic processes which serve as indicators of the highly complex process of desertification and thus play an important role in its monitoring. Ecological degradation triggers off and enhances these morphological activities, which are mainly processes of soil changes, soil erosion, and the transport and accumulation of soils. These alterations of relief and soil result in hydrological changes which have negative effects on land productivity. Both geomorphological and desertification processes are so interwoven that it becomes difficult to differentiate clearly between causes and effects. As the field studies tackled here have been carried out in the sandy regions of western Sudan, special attention is being paid to aeolian erosion and accumulation. Fluvial processes play only a subsidiary role in the processes of desertification there. 相似文献
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27.
Paleorainfall Reconstructions from Pedogenic Magnetic Susceptibility Variations in the Chinese Loess and Paleosols 总被引:2,自引:0,他引:2
The rock magnetic properties of the Chinese loess and paleosols constitute a unique and sensitive record of East Asian paleoclimate through the Quaternary Period. Systematic variations in the concentration and grain size of the magnetic minerals in these sediments have produced systematic variations in the magnetic susceptibility signal, which can be easily and rapidly measured at many sites across the Loess Plateau. Variations in many other rock magnetic properties can be used to identify the key shifts in ferrimagnetic grain size, but magnetic susceptibility alone is sufficiently sensitive to record stadial and interstadial climate stages, as well as glaciations and interglaciations. Past changes in rainfall and monsoon activity for this region are reconstructed from the susceptibility variations. The susceptibility record is calibrated using the modern relationship between rainfall and pedogenic susceptibility on the Loess Plateau. Our rainfall reconstructions identify enhanced summer monsoonal activity in the Chinese Loess Plateau region in the early Holocene and the last interglaciation. In the presently semiarid western area of the plateau, annual precipitation in interglacial times was up to 80% higher than at present; in the more humid southern and eastern areas, values were up to 20% higher than today's levels. During the last glaciation, precipitation decreased across the entire plateau, typically by 25%. The relationship between pedogenic susceptibility, climate, and weathering age was examined over the Northern Hemisphere temperate zone and the observed positive correlation between rainfall and susceptibility indicates that climate, rather than soil age, is the predominant factor that controls pedogenic susceptibility enhancement in loess soils. 相似文献
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I. M. Korrat H. M. Hussein I. Marzouk E. M. Ibrahim R. Abdel-Fattah N. Hurukawa 《Acta Geophysica》2006,54(1):33-49
Seismicity in the northernmost part of the Red Sea has been studied using data from Hurghada Seismological Network in addition
to readings from the existing neighbouring networks. Relocated events in addition to data from national centers are used to
obtain a complete and true picture for the seismicity of the area. The spatial distribution of earthquakes defines three earthquake
zones in the Gulf of Aqaba and three zones at the entrance of the Gulf of Suez and southern tip of Sinai Peninsula. The thermal
activity and the triple junction nature control the activity in this area. The activity defines also an active trend extending
from the southern tip of Sinai Peninsula to the median zone of the Red Sea. The seismicity of this trend is probably related
to the active spreading zone associated with the opening of the Red Sea. The b-values are derived for the entrance areas of the two gulfs and for Gulf of Aqaba. Values of b are 1.35 for the triple junction region, 1.13 for the activity before the 22 November 1995 Gulf of Aqaba mainshock and 1.25
for the aftershocks of this event. 相似文献
30.
F. W. L. Kho B.Sc. P. L. Law B.SCE. M.SCE. M.Sc. Sc.D. S. H. Ibrahim M.S.c Ph.D. J. Sentian B.Sc. M.Sc. 《International Journal of Environmental Science and Technology》2007,4(1):27-34
This paper predicts and compares the carbon monoxide (CO) concentration levels along Sembulan Road for years 2004 and 2014 using CAL3QHC air dispersion model at two major locations, i.e., at Sembulan Roundabout and Sutera Harbour Intersection, Kota Kinabalu, Sabah, Malaysia. The CO concentration “hot-spots” were also identified at Sutera Harbour Intersection, and the highest maximum 1-hr average ground level concentrations of CO modeled for Kpg. Air Sembulan located in the northeast of idling road was 9.33 ppm for year 2004. This study showed that there would be no extreme changes in CO concentration trends for year 2014 although a substantial increase in the number of vehicles is assumed to affect the level of CO concentrations. It was also found that the CO levels would be well below the Malaysian Ambient Air Quality Guidelines of 30 ppm for 1-hour Time-Weighted Average (TWA). Comparisons between the modeled and observed outputs using quantitative data analysis technique and statistical methods indicated that the CAL3QHC predicted results correlated well with measured data. It was predicted that receptors located near to the major intersection, in the long-term would be potentially exposed to relatively higher CO levels. 相似文献