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Search Results: 1 - 10 of 2586 matches for " Mona Fouad Kaiser "
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Impact of the Human Activities on the Local Climate and Environment of the Suez City in Egypt  [PDF]
Mona Fouad Kaiser
International Journal of Geosciences (IJG) , 2014, DOI: 10.4236/ijg.2014.57063
Abstract:

Surface temperature and vegetation are the major land cover changes that significantly affect on the thermal environment. In the present study, remote sensing techniques were applied to identify the relationship between anthropogenic activities and the thermal environment in the North Gulf of Suez area. Results have indicated that the urbanization and agricultural expansion have been increased during the last 25 years. Although urban areas increased from 49 km2 in 1987 to 57 km2 in 2012, the urban heat island-range declined from very high and high, to moderate and low. An expansion in cultivated areas from 3 km2 in 1987 to 26 km2 in 2012 was responsible for the decline. The results of this study provided valuable information for understanding the local thermal changes that associate rapid urbanization and expansion of cultivated areas. Consequently, this work recommends that proper planning and management regimes for land use and cover changes associated with rapid urbanization will result in positive impacts on the local climate and environment.

Comparative Study of the Photocatalytic Activity of Semiconductor Nanostructures and Their Hybrid Metal Nanocomposites on the Photodegradation of Malathion
Dina Mamdouh Fouad,Mona Bakr Mohamed
Journal of Nanomaterials , 2012, DOI: 10.1155/2012/524123
Abstract: This work is devoted to synthesize different semiconductor nanoparticles and their metal-hybrid nanocomposites such as TiO2, Au/TiO2, ZnO, and Au/ZnO. The morphology and crystal structure of the prepared nanomaterials are characterized by the TEM and XRD, respectively. These materials are used as catalysts for the photodegradation of Malathion which is one of the most commonly used pesticides in the developing countries. The degradation of 10 ppm Malathion under ultraviolet (UV) and visible light in the presence of the different synthesized nanocomposites was analyzed with high-performance liquid chromatography (HPLC) and UV-Visible Spectra. A comprehensive study is carried out for the catalytic efficiency of the prepared nanoparticles. Different factors influencing the catalytic photodegradation are investigated, as different light source, surface coverage, and nature of the organic contaminants. The results indicate that hybrid nanocomposite of the semiconductor-metal hybrid serves as a better catalytic system compared with semiconductor nanoparticles themselves.
Photodegradation of Chloridazon Using Coreshell Magnetic Nanocompsites
Dina Mamdouh Fouad,Mona Bakr Mohamed
Journal of Nanotechnology , 2011, DOI: 10.1155/2011/416060
Abstract: A new synthesized magnetic nanoparticle of Fe3O4 and coreshell Fe3O4@Au is prepared chemically. A comparative study between the photocatalytic activity between Fe3O4 and core shell Au-Fe3O4 nanoparticles has been studied on the effect of UV and sun light on the photodegradation of chloridazon. The particle has been prepared using chemical methods and the particle size and shape have been examined via transmission electron microscopy (TEM). Analysis of the degradation of 20?ppm chloridazon under ultraviolet (UV) and visible light was analyzed with high-performance liquid chromatography (HPLC) and UV-Visible Spectra. Influence of different parameters on the activity photodegradation rate has been studied. The results indicate that the Fe3O4@Au nanoparticles are much more active catalyst in presence of sun light than pure Fe3O4 nanomaterials which have maximum absorption at 560?nm. 1. Introduction Magnetic nanoparticles (NPs) have attracted significant interest, due to their numerous attributes such as their low toxicity and biocompatibility; the increasing attention in these materials as well as other composites is determined by the novel magnetic, electronic, optical, and chemical properties, which are different to those of the bulk materials because of the extreme small sizes and the large specific surface areas, and magnetic properties that enable them to be directed by an external magnetic field, in addition to their possibility to separate them from a reaction mixture [1–7]. Iron oxide nanoparticles could be easily oxidized by oxygen present in air and also can react between its self-forming aggregates. Many trials have been carried out to modify the surface during the synthesis or coating process [8–10]. A special class of particular interest of nanocomposite materials is nanoshell particles or core/shell nanocomposites. These core/shell nanocomposites are highly functional materials consisting of thin coatings (1–20?nm) of one particular material deposited on core particles of another different material utilizing certain procedures [11, 12]. Nanocomposites core/shell has attracted a lot of attention owing to their novel-tailored properties which are different from the single-component counterparts (the single core or shell). Now it is possible to synthesize these nanocomposites in desired size and shape and with controlled improved properties such as increased stability, surface area, magnetic, optical, and catalytic properties [13]. Gold surface allows the attachment of molecules with a relative ease using a variety of thiol linkers [14–16]; gold
Current Mode Logic Testing of XOR/XNOR Circuit: A Case Study  [PDF]
Mona M. Fouad, Hassanein H. Amer, Ahmed H. Madian, Mohamed B. Abdelhalim
Circuits and Systems (CS) , 2013, DOI: 10.4236/cs.2013.44049
Abstract:

This paper investigates the issue of testing Current Mode Logic (CML) gates. A three-bit parity checker is used as a case study. It is first shown that, as expected, the stuck-at fault model is not appropriate for testing CML gates. It is then proved that switching the order in which inputs are applied to a gate will affect the minimum test set; this is not the case in conventional voltage mode gates. Both the circuit output and its inverse have to be monitored to reduce the size of the test set.

Induced Salt Tolerance in Common Bean (Phaseolas vulgaris L.) by Gamma Irradiation
Mohamed S. Beltagi,Mona A. Ismail,Fouad H. Mohamed
Pakistan Journal of Biological Sciences , 2006,
Abstract: Dry seeds of common bean (Phaseolas vulgaris L. cv. Nebraska) were subjected to 0, 2 and 32 Krad of gamma rays from a cobalt-60 source and salt stress treatments (0, 1000, 2000 and 3000 ppm) of NaCl. The shoot length of the plants was significantly reduced only at the highest level (3000 ppm) of NaCl, while the root length was significantly inhibited by all NaCl levels. The contents of chlorophyll a and chlorophyll b did not change under all treatments, while carotenoids increased in response gamma irradiation in non-stressed plants. The high dose (32 Krad) of gamma irradiation caused incomplete inhibition of seedling growth which indicated 100% lethality. The low dose (2 Krad) significantly induced the shoot length, leaf area and pod fresh weight under salinity stress. In SDS-PAGE proteins, the total number of protein bands was reduced under all NaCl treatments. The synthesis of salt susceptible molecular weight polypeptides was completely inhibited at all levels of NaCl; while, the synthesis of the salt tolerant molecular weights was inhibited only at the highest level (3000 ppm) of NaCl. Responding against salinity stress, two new polypeptides were synthesized. The low dose (2 Krad) of gamma irradiation induced stability in the total number of protein bands and continuing synthesis of certain polypeptides under the highest level (3000 ppm) of NaCl. A synergistic interaction emerged between NaCl stress (3000 ppm) and nonlethal dose (2 Krad) of gamma irradiation resulted in salt tolerance in common bean (Phaseolas vulgaris L. cv. Nebraska) plants.
Proposed Mac Protocol Versus Ieee 802.15.3a for Multimedia Transmission Over UWB Networks
Nawal Ahmed El-Fishawy;Mona Shokair;Waleed Saad Fouad HIlmy
PIER B , 2008, DOI: 10.2528/PIERB07111812
Abstract: In this paper, a Medium Access Control (MAC) protocol is proposed to investigate Quality of Service (QoS) for multimedia traffic transmitted over Ultra Wide-Band (UWB) networks and increase the system capacity. This enhancement comes from using Wise Algorithm for Link Admission Control (WALAC) which has three suggested versions. The QoS of multimedia transmission is determined in terms of average delay, admission ratio, loss probability, utilization, and the network capacity. In addition, a new parameter is aroused for the network performance. Comparisons between the IEEE 802.15.3a protocol and the proposed one are done. The proposed protocol shows better results in both sparse and dense networks for real time traffic transmission.
High Frequency, Direct Shoot Regeneration from Greenhouse-Derived Leaf Disks of Six Strawberry Cultivars
Fouad H. Mohamed,Mohamed S. Beltagi,Mona A. Ismail,Ginesia F. Omar
Pakistan Journal of Biological Sciences , 2007,
Abstract: Leaf disks derived from either two-month-old GreenHouse-grown (GHD) strawberry plants or in vitro plantlets were cultured on MS media amended with 2 mg L-1 Thidiazuron (TDZ), incubated for four weeks in the dark then for another four weeks under 16/8 h light regime. Regeneration capacity of leaf disks was compared to meristem-derived propagules in six strawberry cultivars. Direct shoot regeneration occurred in all tested cultivars with different frequencies depending on explant source. From GDH leaf disks, the cultivars Camarosa, Gaviota and Seascape produced the highest number of shoots/explant (38, 31 and 31 shoots, respectively). However, optimum number of shoots/explant from in vitro leaf disks was achieved in the cultivars Carlsbad, Chandler and Sweet Charlie (13.3, 12.6 and 12.3 shoots, respectively). In general, regeneration capacity of GHD leaf discs was more than two-folds of that obtained from in vitro leaf disks. The efficiency of meristem culture was intermediate between the above two systems. Rooted plantlets were successfully acclimatized under mist. The only morphological abnormality detected was a white streaked variant observed out of 456 Camarosa plants derived from meristem culture. SDS-PAGE of protein profile proved consistency in banding patterns of mother plants and those derived from direct regeneration or meristem proliferation.
Receipt of Standard Breast Cancer Treatment by African American and White Women
Julie Worthington, John W. Waterbor, Ellen Funkhouser, Carla Falkson, Stacey Cofield, Mona Fouad
International Journal of Medical Sciences , 2008,
Abstract: Objectives: Breast cancer mortality is higher among African Americans than for Whites, though their breast cancer incidence is lower. This study examines whether this disparity may be due to differential receipt of treatment defined as “standard of care” or “addition to standard of care” by the National Comprehensive Cancer Network (NCCN). Design: Incident, female breast cancer cases, 2,203 African American and 7,518 White, diagnosed during 1996-2002 were identified from the Alabama Statewide Cancer Registry. Breast cancer treatment was characterized as whether or not a woman received standard of care as defined by the NCCN. For cases characterized as receiving standard of care, addition to standard of care was also evaluated, defined as receiving at least one additional treatment modality according to NCCN guidelines. Logistic models were used to evaluate racial differences in standard and addition to standard of care and to adjust for age, stage at diagnosis, year of diagnosis and area of residence. Results: No racial differences were found for standard (Prevalence Ratio (PR)=1.00) or for addition to standard of care (PR=1.00) after adjustment for confounders. When the adjusted models were examined separately by age, stage, and area of residence, overall no racial differences were found. Conclusion: No racial differences in standard of care and addition to standard of care for breast cancer treatment were found. Therefore, both African Americans and Whites received comparable treatment according to NCCN guidelines.
Investigations on the Chemical Degradation of Silver Gelatine Prints
Maha Ahmed ALI,Mona Fouad ALI,Mohammed Osama SAKER,Abdel Azez El Bayoumi ABDEL ALEEM
International Journal of Conservation Science , 2012,
Abstract: Photographs are considered composite objects with complex chemical and physical structures. Therefore they are more prone to damage as compared to other objects. Chemical degradation is by far the most common decay form found among photographic collections. This study investigates the chemical degradation of silver gelatin prints (DOP) and the reaction of the image, silver, gelatin, and paper to accelerated aging, to the action of light, and oxidizing gases, in terms of their physical and chemical nature. The test materials used are properly washed and poorly washed grayscale, black-and-white processed images on photographic paper (Black & White Photographic Paper BH 0 Bromofort 6P0661 Tropical from Forte Photochemical Company Vác, Hungary). After exposure, the results were studied by means of visual inspection, amino acid analyzer, Fourier transform infrared and transmission electron microscope. The results were compared with those of the control samples. Our study revealed that the image, silver, gelatin and photographic paper are greatly affected by oxidizing agents and that the effect increased if the photographic prints were inadequately washed at the time of their processing. Furthermore, our results indicated that an increased amount of ammonia and amino acid in the silver gelatin print is a reliable indicator of the degradation of its gelatine emulsion.
The pristine atomic structure of MoS2 monolayer protected from electron radiation damage by graphene
Gerardo Algara-Siller,Simon Kurasch,Mona Sedighi,Ossi Lehtinen,Ute Kaiser
Physics , 2013, DOI: 10.1063/1.4830036
Abstract: Materials can, in principle, be imaged at the level of individual atoms with aberration corrected transmission electron microscopy. However, such resolution can be attained only with very high electron doses. Consequently, radiation damage is often the limiting factor when characterizing sensitive materials. Here, we demonstrate a simple and effective method to increase the electron radiation tolerance of materials by using graphene as protective coating. This leads to an improvement of three orders of magnitude in the radiation tolerance of monolayer MoS2. Further on, we construct samples in different heterostructure configurations to separate the contributions of different radiation damage mechanisms.
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