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      • KCI등재

        Effect of gravity field, initial stress and rotation on the S-waves propagation in a non-homogeneous anisotropic medium with magnetic field

        S. M. Abo-Dahab,A. M. Abd-Alla,Ibrahim H. El-Sirafy 대한기계학회 2014 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.28 No.8

        In this paper, we investigated the propagation of shear wave under the influences of the magnetic field, gravitational field, rotation andinitially stressed in anisotropic non-homogeneous incompressible elastic medium. It is well known in the literature that the earth mediumis not at all initial stress free and homogeneous throughout, but it is initially stressed and non-homogeneous. The frequency equation thatdetermines the velocity of the shear waves has been obtained. Keeping these things in mind, we have discussed the frequency equation inan initially stressed, non-homogeneous medium with gravity field, magnetic field, and rotation. It has been observed that the inhomogeneityparameter, gravity field, magnetic field, and the initial stress play an important role in the propagation of S-waves propagation. Thenumerical values on the dimensionless phase velocities are calculated and presented graphically to illustrate the dependences upon gravityfield, initial stress, magnetic field, anisotropy and rotation comparatively. The results indicate that the effects of gravity field, initialstress, magnetic field, anisotropy, and rotation are very pronounced.

      • KCI등재

        First Measurements of Carbonaceous Aerosol across Urban, Rural and Residential Areas in Jeddah City, Saudi Arabia

        Iqbal M. Ismail,Ahmad S. Summan,Jalal M. Basahi,Essam Hammam,Mohamed F. Yassin,Ibrahim A. Hassan 한국대기환경학회 2021 Asian Journal of Atmospheric Environment (AJAE) Vol.15 No.2

        Concentrations of black carbon (BC), organic carbon (OC), and total suspended particulate matter (TSP) were simultaneously assessed in urban, rural and residential areas in Jeddah city for one year from January to December 2017. It was aimed in the present study to provide information about the spatial and seasonal variability of these aerosol species in Jeddah, and insight into sources, processes and effects of meteorological conditions. To the best of our knowledge, this is the first study investigating the variability of carbonaceous aerosols (OC and BC) in Saudi Arabia. The average concentrations of OC, BC, and TSP varied spatially and temporally. The annual average concentrations of OC, BC, and TSP were 134.05, 7.16, and 569.41 μg m-3 and 34.32, 5.14, and 240.64 μg m-3 and 10.67, 4.39 and 101.31 μg m-3 in the urban, residential and rural areas, respectively. Moreover, there was a clear seasonal variation in the concentration of carbonaceous aerosols; the highest concentrations were recorded in February and September, while the lowest concentrations of OC were recorded during April, May and August in the urban, residential and rural sites, respectively. Nevertheless, the lowest concentrations of BC were recorded during March in the urban and residential sites and during November in the rural site. The relative concentrations of OC and BC to the TSP were relatively high, and they have a significant correlation with prevalent wind speed (-0.636, and -0.581 in the urban area), (-0.539 and -0.511 in the residential area), and (-0.508 and -0.501 in the rural area), respectively. The marked differences in the concentrations of BC and OC were reflected on OC/BC ratio, which is a good representative of different source types. This preliminary study showed that the potential local sources were emissions from traffic (fossil fuel), biomass burning, anthropogenic activities (e.g. car drifting and outdoor cooking), and industrial activities. The present study suggest the presence of highly inefficient combustion sources and highlight the need for the regulation of such emissions.

      • KCI등재

        Nematicidal Compounds from the Leaves of Schinus terebinthifolius Against Root-knot Nematode, Meloidogyne incognita Infecting Tomato

        Fatma M. Abdel Bar,Dina S. Ibrahim,Sahar R. Gedara,Mohammed S. Abdel-Raziq,Ahmed M. Zaghloul 한국생약학회 2018 Natural Product Sciences Vol.24 No.4

        The root-knot nematode, Meloidogyne incognita caused a serious damage to many plants. The phenolic components of the leaves of Schinus terebinthifolius were investigated as potential nematicidal agents for M. incognita. Nine compounds were isolated and characterized as viz., 1,2,3,4,6-pentagalloyl glucose (1), kaempferol-3-O-a-L-rhamnoside (Afzelin) (2), quercetin-3-O-a-L-rhamnoside (Quercetrin) (3), myricetin (4), myricetin-3-O-a-L-rhamnoside (Myricetrin) (5), methylgallate (6), protocatechuic acid (7), quercetin (8), and gallic acid (9) using nuclear magnetic resonance (NMR) spectroscopy. Compound 1 showed pronounced nematicidal activity compared to Oxamyl as a positive control. It showed the lowest eggs-hatchability (34%) and the highest mortality in nematode population (21% after 72 hours of treatment) at a concentration of 200 mg/mL. It exhibited the best suppressed total nematode population, root galling and number of eggmasses in infected tomato plants. The total carbohydrates and proteins were also significantly induced by 1 with reduction in total phenolics and increase in defense-related proteins. Thus, compound 1 could be a promising, more safe and effective natural nematicidal agent for the control of root-knot nematodes.

      • KCI등재

        Environmentally benign Scouring of Cotton Knits Using Locally Produced Acid Pectinase Enzyme

        Nabil A. Ibrahim,Basma M. Eid,Mohamed S. Abdel Aziz,Soha M. Hamdy,Safaa E. AbdAllah 한국섬유공학회 2019 Fibers and polymers Vol.20 No.4

        The main task of the present study is to pre-screen selected fungal strain (Fusarium oxysporum M1-EGY) isolatedfrom local agriculture soil and optimize cultivation conditions for an acid pectinase production. Experimental resultsdemonstrated the optimum conditions for achieving the highest enzyme activity (14.80 U/ml) were found to be: incubationperiod (8 days) at pH (5), temperature (30 oC), and shaking rate (150 rpm), apple pectin carbon source (2 %), and ammoniumphosphate as nitrogen source (0.2 gN/l). The positive impacts of utilizing the produced crude acid-pectinase in eco-friendlyscouring of various cotton knits as well as their subsequent bleaching and reactive dyeing have been confirmed. Additionally,the use of local resources for an acid pectinase production would encourage and promote local production of textile enzymesand their potential applications in Egyptian textile sector, taking in consideration efficiency, textile quality, environmental andeconomy concerns.

      • KCI등재후보

        Potential of Activated Carbon Derived from Local Common Reed in the Refining of Raw Cane Sugar

        Ibrahim D-Abdullah,Badie S. Girgis,Yassin M. Tmerek,Elsaid H. Badawy 한국탄소학회 2010 Carbon Letters Vol.11 No.3

        Common reed (Fragmites australis), a local invasive grass, was investigated as a possible feedstock for the production of activated carbon. Dried crushed stems were subjected to impregnation with phosphoric acid (30, 40 and 50%) followed by pyrolysis at 400~500℃ with final washing and drying. Obtained carbons were characterized by determining: carbon yield, ash content, slurry pH, textural properties and capacity to remove color bodies from factory-grade sugar liquor. Produced carbons possessed surface area up to 700 m2/g, total pore volumes up to 0.37 cm3/g, and proved to be microporous in nature. Decolorization of hot sugar liquor at 80℃ showed degrees of color removal of 60 up to 77% from initial color of 1100~1300 ICU, at a carbon dose of 1.0 g/100 ml liquor. No correlation seems to hold between synthesis conditions and % R but depends on the degree of microporosity. A commercial activated carbon N showed a comparative better color removal capacity of 91%. Common reed proved to be a viable carbon precursor for production of good adsorbing carbon suitable for decolorization in the sugar industry, as well as in other environmental remediation processes.

      • KCI등재

        New issue of GaN nanoparticles solar cell

        M.A. Qaeed,K. Ibrahim,K.M.A. Saron,M.S. Mukhlif,A. Ismail,Nezar G. Elfadill,Khaled M. Chahrour,Q.N. Abdullah,K.S.A. Aldroobi 한국물리학회 2015 Current Applied Physics Vol.15 No.4

        This study involves the synthesis of gallium nitride (GaN) nanoparticles (NPs) under different low temperatures using a simple chemical method. The nanoparticles are spin coated on Si substrate to fabricate the solar cell. The FESEM images obtained indicate the presence of cubic GaN nanoparticle with average diameter of 50 nm synthesized at 90 ℃. The spin coating technique deposited n-GaN NPs/Si(111) produced a heterojunction solar cell with fill factor of 0.56 and conversion efficiency of 2.06%. Based on these results, this study proposes a novel low cost technique for the fabrication of GaN NPs solar cells.

      • SCIESCOPUSKCI등재

        ENSILING CHARACTERISTICS AND NUTRITIVE VALUE OF GUINEA GRASS (Panicum maximum, Jacq.) AS AFFECTED BY GROWTH STAGE

        Ibrahim, M.N.M.,Premaratne, S.,Perera, H.G.D. Asian Australasian Association of Animal Productio 1989 Animal Bioscience Vol.2 No.2

        An experiment was conducted to study the effect of frequency of defoliation on the ensiling characteristics and nutritive value of Guineaecotype 'A' (Panicum maximum Jacq) grass. Guinea grass harvested at 2, 3, 4, 5, 6, 7, 8, 9, 10 and 12-week cutting intervals was chopped (2 cm) and ensiled alone or with the addition of coconut (Cocos nucifera L.) meal (w/w-fresh weight basis), for periods of 6, 7 or 8 weeks in 2-litre laboratory silos. Dry matter, water soluble carbohydrates, lactic acid, pH, ash, nitrogen and digestibility in vitro were measured in representative samples of preensiled and ensiled material. Dry matter content of silages prepared from herbage harvested at 2 and 3 weeks intervals was lower (P<0.05) compared to longer defoliation intervals. The pH of silage prepared from herbage over 8 weeks old were higher (P<0.05) than those harvested below 8 weeks. The water soluble carbohydrate content of silage prepared from 3-weekly defoliated herbage was higher (P<0.05) than those prepared from longer periods. Lengthened growth period decreased (P<0.001) the crude protein content of the ensiled material, whereas the addition of coconut meal resulted in marginal increases. In vitro organic matter digestibility of the silages decreased (P<0.05) with the increase in forage maturity.

      • KCI등재후보

        Effects of basil leaf (ocimum basilicum) marination on sensory attributes of spent layer meat

        Ibrahim, M.S.,Ibrahim, N.T.,Zaharadeen, I.M. Korea FoodHealth Convergence Association 2018 식품보건융합연구 (KJFHC) Vol.4 No.3

        This research was conducted at agric physical lab, Department of Animal science, Faculty of Agriculture to determines the effects of marinating spent layer meat with basil leaf paste on drip loss and sensory attributes under different post mortem conditions. In the light of this, the poultry industry is obliged to continuously grow for a steady supply of quality poultry meat. Marinating the spent layer hen's meat with fresh basil leaves (Ocimum basilicum) in addition to subjecting the meat to 0, 6, 12, and at 24 hours post mortem aging before cooking increased it's organoleptic attributes which was readily acceptable to consumers. Marination of meat with herbs or spices like basil leaves paste had enhanced consumer's preference for taste, texture aroma, colour and overall acceptance. Marination improved consumer acceptance of spent layer meat irrespective of parts and post mortem aging. However, the majority of the respondents preferred meat marinated and subjected to 12 hours of post mortem aging. It is recommended that more quantity of marinate should be added further studies should in order to determine more effect of fresh basil leaves rough paste. And more hours of postmortem aging should be increased in order to determine more effect of fresh basil leaves rough paste marinate.

      • KCI등재

        Studying the operation of MOSFET RC-phase shift oscillator under different environmental conditions

        Ibrahim Reiham O.,Abd El-Azeem S.M.,El-Ghanam S.M.,Soliman F.A.S. 한국원자력학회 2020 Nuclear Engineering and Technology Vol.52 No.8

        The present work was mainly concerned with studying the operation of RC-phase shift oscillator based on MOSFET type 2N6660 under the influence of different temperature levels ranging from room temperature (25 C) up-to135 C and gamma-irradiation up-to 3.5 kGy. In this concern, both the static (IeV) characteristic curves of MOSFET devices and the output signal of the proposed oscillator were recorded under ascending levels of both temperature and gamma-irradiation. From which, it is clearly shown that the drain current was decreased from 0.22 A, measured at 25 C, down to 0.163 A, at 135 C. On the other hand, its value was increased up-to 0.49 A, whenever the device was exposed to gamma-rays dose of 3.5 kGy. Considering RC-phase shift oscillator, the oscillation frequency and output pk-pk voltage were decreased whenever MOSFET device exposed to gamma radiation by ratio 54.9 and 91%, respectively. While, whenever MOSFET device exposed to temperature the previously mentioned parameters were shown to be decreased by ratio 2.07 and 46.2%.

      • SCIESCOPUSKCI등재

        Release of Mineral Elements from Tropical Feeds during Degradation in the Rumen

        Ibrahim, M.N.M.,Zemmelink, G.,Tamminga, S. Asian Australasian Association of Animal Productio 1998 Animal Bioscience Vol.11 No.5

        The proportion of dry matter (DM) and mineral elements (Ca, Mg, P, Na, K, Zn) released from eight feeds (2 rice straws, RSI and RS2; 2 grasses, NB21 and guinea; 2 leguminous fodders, glyricidia and erythrina; jak leaves and rice bran) were studied using the nylon bag procedure. Bag incubations up to 10 days were performed in the rumen of cows fed on a ration consisting of 50% wheat straw and 50% hay. Both the type of feed and the incubation time in the rumen significantly influenced (p < 0.01) the proportion of minerals released. In legumes, jak leaves and rice bran about 80% of the potentially degradable DM fraction was solubilized within 24 h in the rumen, and with the grasses, rice straws and jak leaves a considerable proportion of DM was released between 48 and 240 h in the rumen. During the early hours of incubation (up to 24 h) there were distinct differences between and within the feed classes in their ability to release all mineral elements studied. In all test feeds, high proportions of Mg and K were released within 24 h. Some feeds showed a tendency to ad/absorb Ca (grasses, rice straws and rice bran), P (jak leaves, rice straws), Na (glyricidia and rice bran) and Zn (jak leaves) from water and rumen fluid, and this was partly related to the low initial concentration. In terms of absolute quantity of mineral released, legumes (erythrina is superior to glyricidia) are a good source of Ca, Mg, P and Zn, and jak leaves a good source of Ca and Na. Within grasses, guinea contains appreciable quantity of available Mg and P. Rice bran is rich in available Mg, P and Zn.

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