937 resultados para Receipts (Acknowledgments)--Egypt--Karanis (Extinct city)


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This work focuses on four marine sites in the Mediterranean Sea around the Nile Delta, Egypt. Surface water samples were collected seasonally during 2003. The concentrations of some heavy metals in dissolved form (Fe, Mn, Zn, Cu, Ni and Pb) are evaluated. The levels of heavy metals in the coastal waters were 11.92-30.4512µglˉ¹ for Fe; 5.79-17.36 µglˉ¹ for Zn; 0.30-0.83µglˉ¹ for Cu; 0.51-2.90µglˉ¹ for Ni and 0.53-10.31µglˉ¹ for Pb. These are compared, with sites in the estuaries and outlets of the Nile Delta. Fe (19.72-60.33µglˉ¹); Mn (12.63-35.60µglˉ¹); Zn (2.67-22.00); Cu (0.56-1.67µglˉ¹); Ni (1.43-3.73µglˉ¹); Pb (1.72-59.7µglˉ¹). The results showed a remarkable decrease in the concentrations of different heavy metals with increased salinity. Comparing the present data with the minimal risk concentration reported by WQC, the distribution of heavy metals was significantly lower in coastal sea water of the Mediterranean Sea off Egypt. The study indicated also that the average contents of Ni and Pb are slightly high in the area of water exchange than those reported by WQC.

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Increases in coastal development and human activities leading to sedimentation degrade the quality of water; disturb the natural structure and functions of aquatic communities. The Suez Gulf is a large semi-closed area (~625 km long coastline).The assemblages of bottom fauna were studied qualitatively and quantitatively in the shallow intertidal waters along the western coast of the Suez Gulf. The quality of seawater and sediment structures were analyzed. The distribution of macro-benthos included a total of 38 species of Gastropoda and 9 Bivalvia; and 25 species from the other invertebrates included 7 groups namely, Rhizostoma, Polychaeta, Cirripedia, Amphipoda, Isopoda, Decapoda and Echinodermata. The most dominant group among invertebrate groups was the Polychaeta which included 4 species: Hydroides elegans, Perinereis cultilifera, Perinereis nuntia and Ophelina acuminata. The Cirripedia were represented by 3 species namely, Balanus amphitrite, Chithamalus challengeri and Tetraclita squamosa. The variations in the numerical abundance and biomass of bottom fauna studied between the observation periods and at sampling sites. There was a marked increase in benthos biomass at St. IV (Ras Gharib) yielding an average of 318.8 g/m² in which the gastropod community represented the dominant species in collected samples reaching 270.28 g/m² (84.4% of the total biomass) and numerically numbered 116 ind./m². Veliger larvae of bivalves and gastropods appeared to be present in the plankton for long periods and their production seems to be continuous throughout the year. In the intertidal zone of the Suez Gulf, the values of pH varied within narrow limits. Water temperature and salinity seemed to be important in the distribution and abundance of the macro-benthos communities in the study areas. The organic content in shallow intertidal waters and sediments indicated high values in the central part of the Gulf of Suez.

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Total concentrations and chemical forms of heavy metals in sediment samples from the Gulf of Suez and the northern part of the Red Sea, collected during January 2003, were determined by atomic absorption spectrometry. Maximum concentrations of 49.56, 65.42, 33.52 and 3.52 µg/g were recorded for total Cu, Zn, Pb and Cd respectively at Adabiya location. These may reflect the high contribution of land-based activities in the northern part of the Gulf. Also, high percentages of heavy metals were found in the residual fraction (Cu=78.61, Zn=77.10 and Pb=66.80%) while a high percentage of Cd was found in the carbonate fraction (45.82%). However, few or negligible percentages were recorded in the exchangeable fractions (Cu=0.51, Zn=1.57 and Pb=1.74%). Concentration of Cd in the exchangeable fraction was too low to be detected.

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Lake Edku is one of the Nile Delta lakes. It is subjected to contaminations by several anthropogenic materials such as trace elements and other wastes. The distribution of the different chemical forms of copper and manganese has been studied using sequential extraction techniques. Chemical analysis of the sediments shows that CaCO sub(3) ranged from 3.7% to 9.6% and organic matter from 3.06% to 8.11%. The results indicate that the distribution of manganese among the six chemical forms in the sediments of the lake obeys the following order: Mn-residual>Mn-carbonate>Mn-moderately reducible>Mn-organic form>Mn-exchangeable > Mn-easily reducible fraction. Also, the data revealed that more than 50% of the total manganese was found in the residual form, while the remainder was distributed among the other forms. In contrast, more than 70% of the total copper content was associated with the five chemical forms (exchangeable, carbonate, easily and moderately reducible and organic forms). Generally, the enrichment of manganese in the residual form revealed the important role in building up of clay minerals, while the distribution of copper among the different forms reflects an important role in biological and biochemical processes.

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Trace elements associated with organic subfractions (humic, fulvic, and non-humic substances) were identified for seven core sediments from Lake Mariut, Egypt. Results indicated that the amounts of trace metals in humic acid and non-humic substances decreased in the following order: Zn>Cu>Pb>Cr>Cd, while in fulvic acid the order the order was Cu>Zn>Pb>Cr>Cd. There is a higher contribution of Zn, Pb, Cu and Cr in humic acid compared to fulvic acid in most samples. Slight changes in the amounts of cadmium bounded with humic and fulvic acids was also found.

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Based on the freshwater and seawater budgets, the mean in/out water fluxes as well as the monthly changes in freshwater content were determined in Lake Manzalah. About 6693 x 10^6m^3 of fresh and brackish water inflow to the lake annually through the main drains discharging into the southeastern basin. Allowances of precipitation (105.7 x 10^6m^3/y) and evaporation (1075 x 10^6m^3/y) yield a net runoff of 5723 x 10^6m^3/y. The average changes in the freshwater content (dF) of the lake was 547.0 x 10^6m^3 with the maximum i.e. 72.4 x 10^6m^3 in July. Using the quantity of inflowing and outflowing water through Boughaz El-Gamil (Lake-Sea connection), the change in water volume relative to sea level change was 549 x 10^6m^3/y. The sea-level height (dh) induced an average monthly change of 6.5 cm. Using the amount of freshwater discharge as well as the lake volume, the lake water is replaced every 48 days.

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This study includes determination and discussion of the texture and heavy mineral compositions of some modem Nile Delta coastal sands (river, coastal dune, beach-face, and nearshore marine) in order to delineate the process and factors that regulate the size distribution of heavy mineral grains comprising these coastal sands. Textural analysis of unseparated bulk samples indicate that the examined four types of sands differ in their mean grain sizes and degree of sorting. However, analysis of size distribution curves of 10 heavy mineral species or group of species in the four environments having the same general shape and nearly similar in that general order of arrangement. However, these curves vary both in median sizes and sorting. The size distribution of a heavy mineral in the Nile Delta coastal sands appear to depend on: (1) range of grain size fractions in each sample, (2) relative availability of heavy mineral in each size grade of the sample, (3) specific gravity of minerals comprising these sands, and (4) some other unknown factor or factors. Results of size measurement of heavy minerals indicated that increasing specific gravity is accompanied by increasing fineness of the heavy minerals. This study may be useful in search for marine placers and understanding the processes of grain-sorting on the sea beaches.

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Charles Darwin the research ship undertook an Oceanographic Cruise in 1986, CD 86/17 of the North Arabian Sea. Sediment cores were collected between 15° and 25°N. In this study sediment cores collected from deep Indus and Oman basins (CD 1715, CD 1730, CD 1738) have been analyzed for mineralogy, water content and porosity. In general, the cores are mainly composed of clay to silt sized terrigenous and biogenic constituents. Quartz, chlorite and illite are the common minerals of Arabian Sea sediments. Porosity determined by water content of sediments has been correlated with quartz/chlorite and quartz/illite peak ratios to show a relationship between mineral composition and physical properties.

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Surface- and bottom-water samples were collected from October 1996 to August 1997 to study levels of iron, copper, and cadmium species in their dissolved labile as well as non-labile and particulate forms in the waters of El-Mex Bay. The results showed that the non-labile concentration of the metals was generally more abundant than that of the labile form: its content reached more than 90% of the total dissolved metal for Cu and more than 80% for Fe. The particulate form was almost at the level of the labile form. The annual concentration of the trace metals of the labile form was 13 µglˉ¹ for Fe; 3µglˉ¹ for Cu, and 1.2 µglˉ¹ for Cd in the surface- and bottom-waters.

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Firms and other organizations use Technology Roadmapping (TRM) extensively as a framework for supporting research and development of future technologies and products that could sustain a competitive advantage. While the importance of technology strategy has received more attention in recent years, few research studies have examined how roadmapping processes are used to explore the potential convergence of products and services that may be developed in the future. The aim of this paper is to introduce an integrated roadmapping process for services, devices and technologies capable of implementing a smart city development R&D project in Korea. The paper applies a QFD (Quality Function Deployment) method to establish interconnections between services and devices, and between devices and technologies. The method is illustrated by a detailed case study, which shows how different types of roadmap can be coordinated with each other to produce a clear representation of the technological changes and uncertainties associated with the strategic planning of complex innovations. © 2012 Elsevier Inc.

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The global trend towards urbanization means that over half of the world's population now lives in cities. Cities use energy in different proportions to national energy use averages, typically corresponding to whether a country is industrialized or developing. Cities in industrialized countries tend to use less energy per capita than the national average while cities in developing countries use more. This paper looks at existing World Bank data in respect to urban energy consumption, the emissions inventory work done by New York City, and discusses how this data highlights the need for a focus on: energy policy for buildings in industrialized cities; masterplanning and new construction standards in developing cities; and how urban energy policy can become more effective in reducing urban greenhouse gas emissions.

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Cities may be responsible for up to 70% of global carbon emissions and 75% of global energy consumption and by 2050 it is estimated that 70% of the world's population could live in cities. The critical challenge for contemporary urbanism, therefore, is to understand how to develop the knowledge, capacity and capability for public agencies, the private sector and multiple users in city regions systemically to re-engineer their built environment and urban infrastructure in response to climate change and resource constraints. Re-Engineering the City 2020-2050: Urban Foresight and Transition Management (Retrofit 2050) is a major new interdisciplinary project funded under the Engineering and Physical Science Research Council's (EPSRC) Sustainable Urban Environments Programme which seeks to address this challenge. This briefing describes the background and conceptual framing of Retrofit 2050 project, its aims and objectives and research approach.