Pub Date : 2020-06-01DOI: 10.21608/absb.2020.111459
M. Morad, S. Attia, S. Mohamed, M. Moharam, R. Abou-shahba, M. Rashad
This study investigates the electrochemical evaluation of the activated carbon (AC) prepared from pomegranate peels which were collected, dried, carbonized and finally activated with KOH at different temperatures. The characterization of the as-prepared AC revealed an amorphous type of carbon and densely layer-stacking sheets with an interconnected micro porous network with a remarkable 3128.86m2g-1 surface area. The as-synthesized AC displayed a remarkable capacitance of 126 F g-1 at 0.5 A g-1with a storage retention of 137 % after 2000 cycles at a current density of 2 A g-1. Meanwhile, the realistic symmetrical simulation has been installed, it shows an energy density of 4.58 W h kg-1 at a power density of 244 W kg-1 with a storage retention of 66 % of the initial capacity at a current density of 2 A g-1 after 2000 cycles. Overall, these results demonstrate that for supercapacitors evaluation, the AC electrode can be considered a successful electrode material.
研究了石榴皮在不同温度下经干燥、炭化、KOH活化制备的活性炭的电化学性能。表征结果表明，所制备的AC为非晶型碳，具有致密的层状堆叠层，具有相互连接的微孔网络，其表面积达到了惊人的3128.86m2g-1。合成的交流电在0.5 a g-1电流下的电容值为126 F -1，在2 a g-1电流密度下循环2000次后的存储保留率为137%。同时，进行了真实对称仿真，结果表明，当功率密度为244w kg-1时，电池的能量密度为4.58 W h kg-1，当电流密度为2a g-1时，经过2000次循环后，电池的储能容量为初始容量的66%。总的来说，这些结果表明，对于超级电容器的评估，交流电极可以被认为是一种成功的电极材料。
{"title":"PREPARATION AND ELECTROCHEMICAL BEHAVIOR OF THE ACTIVATED CARBON FROM POMEGRANATE PEELS AS ENERGY-STORAGE MATERIALS","authors":"M. Morad, S. Attia, S. Mohamed, M. Moharam, R. Abou-shahba, M. Rashad","doi":"10.21608/absb.2020.111459","DOIUrl":"https://doi.org/10.21608/absb.2020.111459","url":null,"abstract":"This study investigates the electrochemical evaluation of the activated carbon (AC) prepared from pomegranate peels which were collected, dried, carbonized and finally activated with KOH at different temperatures. The characterization of the as-prepared AC revealed an amorphous type of carbon and densely layer-stacking sheets with an interconnected micro porous network with a remarkable 3128.86m2g-1 surface area. The as-synthesized AC displayed a remarkable capacitance of 126 F g-1 at 0.5 A g-1with a storage retention of 137 % after 2000 cycles at a current density of 2 A g-1. Meanwhile, the realistic symmetrical simulation has been installed, it shows an energy density of 4.58 W h kg-1 at a power density of 244 W kg-1 with a storage retention of 66 % of the initial capacity at a current density of 2 A g-1 after 2000 cycles. Overall, these results demonstrate that for supercapacitors evaluation, the AC electrode can be considered a successful electrode material.","PeriodicalId":7687,"journal":{"name":"Al-Azhar Bulletin of Science","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90041151","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-06-01DOI: 10.21608/absb.2020.111469
A. Swelam, Y. Gedamy, A. El.shahed
The present study aims to synthesize an activated carbon adsorbent (S-AC, P-AC and OH-AC) from polystyrene divinyl benzene waste under different carbonization temperature (450oC and 900 oC and activation conditions (H2SO4, H3PO4 or NaOH). It being characterized and applied as an adsorbent for manganese removal from groundwater. FTIR results indicate that the changes in the peak intensities clear that the binding process was occurring on the surface of the adsorbent. Different factors such as solution pH, adsorbent dosage, contact time, temperature and Mn(II) initial concentration were investigated. The results showed that manganese adsorption capacity decreases with the increase of the carbonization temperature (900oC) and of activating agent H2SO4 > H3PO4 >NaOH. Kinetically, it was shown that the activation temperature of 450oC is the best temperature for activating the adsorbent carbons. The pseudo-first-order model is appropriate for predicting the adsorption process of Mn(II) onto the P-AC 450oC, P-AC 900oC and OH-AC 900oC, while the pseudo-second-order model is appropriate for predicting the adsorption process of Mn(II) onto the both S-AC 450oC, S-AC 900oC, OH-AC 450oCand OH-AC 900oC. Thermodynamic calculations affirmed that Mn(II) adsorption onto S-AC and P-AC was an endothermic process while onto OH-AC was exothermic process. Finally, the results suggested that the prepared S-AC has high adsorption capacities for Mn(II) compared with other adsorbents, such as P-AC and OH-AC. Therefore, S-AC 450oCcan be used in the groundwater treatment unit.
{"title":"PREPARATION OF ACTIVATED CARBON FROM ION EXCHANGE RESIN WASTE AND ITS APPLICATION FOR MANGANESE REMOVAL FROM GROUNDWATER","authors":"A. Swelam, Y. Gedamy, A. El.shahed","doi":"10.21608/absb.2020.111469","DOIUrl":"https://doi.org/10.21608/absb.2020.111469","url":null,"abstract":"The present study aims to synthesize an activated carbon adsorbent (S-AC, P-AC and OH-AC) from polystyrene divinyl benzene waste under different carbonization temperature (450oC and 900 oC and activation conditions (H2SO4, H3PO4 or NaOH). It being characterized and applied as an adsorbent for manganese removal from groundwater. FTIR results indicate that the changes in the peak intensities clear that the binding process was occurring on the surface of the adsorbent. Different factors such as solution pH, adsorbent dosage, contact time, temperature and Mn(II) initial concentration were investigated. The results showed that manganese adsorption capacity decreases with the increase of the carbonization temperature (900oC) and of activating agent H2SO4 > H3PO4 >NaOH. Kinetically, it was shown that the activation temperature of 450oC is the best temperature for activating the adsorbent carbons. The pseudo-first-order model is appropriate for predicting the adsorption process of Mn(II) onto the P-AC 450oC, P-AC 900oC and OH-AC 900oC, while the pseudo-second-order model is appropriate for predicting the adsorption process of Mn(II) onto the both S-AC 450oC, S-AC 900oC, OH-AC 450oCand OH-AC 900oC. Thermodynamic calculations affirmed that Mn(II) adsorption onto S-AC and P-AC was an endothermic process while onto OH-AC was exothermic process. Finally, the results suggested that the prepared S-AC has high adsorption capacities for Mn(II) compared with other adsorbents, such as P-AC and OH-AC. Therefore, S-AC 450oCcan be used in the groundwater treatment unit.","PeriodicalId":7687,"journal":{"name":"Al-Azhar Bulletin of Science","volume":"56 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82469416","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-06-01DOI: 10.21608/absb.2020.111480
H. Shawky, N. Eldabe, K. Kamel, Esmat A. Abd-Aziz
The motion of a Carreau nanofluid past an infinite vertical non-linear permeable stretching sheet embedded in a non-Darcy porous medium is investigated. It is stressed by a uniform external magnetic field. The thermal radiation and heat generation are taken in consideration as well as Brownian motion with thermophoresis, chemical reaction and partial slip velocity at the boundary layer. The nonlinear partial differential equations describing the motion with heat and mass transfer are transformed to non-linear ordinary differential equations and solved by using Runge-Kutta method with approbriate boundary conditions. The effects of the physical parameters of the problem on the obtained solutions are discussed numerically and graphically. Through the section of discussion the skin friction and the rate of heat and mass transfer are computed. It is found that these physical parameters play an important rules to control the obtained velocity, temperature and concentration of the fluid.
{"title":"RADIATION EFFECT ON MAGNETOHYDRODYNAMIC CARREAU NANOFLUID FLOW PAST NON-LINEAR PERMEABLE HEATED STRETCHING SHEET WITH PARTIAL SLIP","authors":"H. Shawky, N. Eldabe, K. Kamel, Esmat A. Abd-Aziz","doi":"10.21608/absb.2020.111480","DOIUrl":"https://doi.org/10.21608/absb.2020.111480","url":null,"abstract":"The motion of a Carreau nanofluid past an infinite vertical non-linear permeable stretching sheet embedded in a non-Darcy porous medium is investigated. It is stressed by a uniform external magnetic field. The thermal radiation and heat generation are taken in consideration as well as Brownian motion with thermophoresis, chemical reaction and partial slip velocity at the boundary layer. The nonlinear partial differential equations describing the motion with heat and mass transfer are transformed to non-linear ordinary differential equations and solved by using Runge-Kutta method with approbriate boundary conditions. The effects of the physical parameters of the problem on the obtained solutions are discussed numerically and graphically. Through the section of discussion the skin friction and the rate of heat and mass transfer are computed. It is found that these physical parameters play an important rules to control the obtained velocity, temperature and concentration of the fluid.","PeriodicalId":7687,"journal":{"name":"Al-Azhar Bulletin of Science","volume":"33 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86568612","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-06-01DOI: 10.21608/absb.2020.111474
Amr Gangan, M. ElSabbagh, M. Bedair, M. El-Sabbah, A. Fahmy
Electrochemical properties of thin silicon oxy carbide films were investigated as anticorrosive coatings. The film was deposited on low carbon steel substrate by radio frequency capacitive coupled plasma technique using tetraethyl ortho silicate (TEOS) as a precursor and Ar was used as a carrier gas in dependence on the applied power. The chemical composition and morphological of the deposited films were examined by energy-dispersive X-ray spectroscopy (EDX) coupled with scanning electron microscopy (SEM). The SEM results confirm a pinhole-free layer of oxy carbide was formed on the steel surface after plasma treatment. The corrosion resistance of the coatings was analyzed by potentiodynamic polarization and electrochemical spectroscopy (EIS) in 3.5% NaCl solution at room temperature. The electrochemical results show remarkable corrosion resistance enhancement after plasma treatments. The corrosion current (icorr) is significantly reduced from 12 µA/cm2 for the blank sample to 1 and 0.3 µA/cm2 for treated samples at 50, and 100 W, respectively. A marked increase of the protective properties was detected by 100 W sample with protective efficiency more than 98 % at room temperature.
{"title":"PLASMA POWER IMPACT ON ELECTROCHEMICAL PERFORMANCE OF LOW CARBON STEEL COATED BY PLASMA THIN TEOS FILMS","authors":"Amr Gangan, M. ElSabbagh, M. Bedair, M. El-Sabbah, A. Fahmy","doi":"10.21608/absb.2020.111474","DOIUrl":"https://doi.org/10.21608/absb.2020.111474","url":null,"abstract":"Electrochemical properties of thin silicon oxy carbide films were investigated as anticorrosive coatings. The film was deposited on low carbon steel substrate by radio frequency capacitive coupled plasma technique using tetraethyl ortho silicate (TEOS) as a precursor and Ar was used as a carrier gas in dependence on the applied power. The chemical composition and morphological of the deposited films were examined by energy-dispersive X-ray spectroscopy (EDX) coupled with scanning electron microscopy (SEM). The SEM results confirm a pinhole-free layer of oxy carbide was formed on the steel surface after plasma treatment. The corrosion resistance of the coatings was analyzed by potentiodynamic polarization and electrochemical spectroscopy (EIS) in 3.5% NaCl solution at room temperature. The electrochemical results show remarkable corrosion resistance enhancement after plasma treatments. The corrosion current (icorr) is significantly reduced from 12 µA/cm2 for the blank sample to 1 and 0.3 µA/cm2 for treated samples at 50, and 100 W, respectively. A marked increase of the protective properties was detected by 100 W sample with protective efficiency more than 98 % at room temperature.","PeriodicalId":7687,"journal":{"name":"Al-Azhar Bulletin of Science","volume":"39 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85284435","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-06-20DOI: 10.21608/absb.2019.80483
G. Attiaa, A. Abdou, S. Amir, D. Mousa
The present work deals with the identification of the generating capacity of oil generation and the hydrocarbon potentiality of the Bahariya Formation in Gebel El-Dist section and the Salam-1X well. This is depending on the organic geochemical analyses by using LECO SC632 and Rock Eval-6 pyrolysis techniques. The analysis shows that the studied samples of Gebel El-Dist are poor to fair organic richness, with poor hydrocarbon potentiality. The maturity evaluation using Tmax showed that the studied samples have immature thermal maturation not reaching the stage of oil and gas generation. Also, the analyses revealed that the studied kerogen is type III kerogen originated mainly from terrestrial plant debris and aquatic organic matter. The expected generated HC is mainly gas. The studied Salam-1X samples are poor to good organic richness, with poor to good source potiental. The studied samples are marginally mature to mature thermal maturation reaching the stage oil generation. The kerogen type is a mixture of type III/II kerogen derived mainly from mixed organic sources.
{"title":"CONTRIBUTION TO SOURCE ROCK EVALUATION OF THE BAHARIYA FORMATION IN SURFACE AND SUBSURFACE SECTIONS, NORTH WESTERN DESERT, EGYPT","authors":"G. Attiaa, A. Abdou, S. Amir, D. Mousa","doi":"10.21608/absb.2019.80483","DOIUrl":"https://doi.org/10.21608/absb.2019.80483","url":null,"abstract":"The present work deals with the identification of the generating capacity of oil generation and the hydrocarbon potentiality of the Bahariya Formation in Gebel El-Dist section and the Salam-1X well. This is depending on the organic geochemical analyses by using LECO SC632 and Rock Eval-6 pyrolysis techniques. The analysis shows that the studied samples of Gebel El-Dist are poor to fair organic richness, with poor hydrocarbon potentiality. The maturity evaluation using Tmax showed that the studied samples have immature thermal maturation not reaching the stage of oil and gas generation. Also, the analyses revealed that the studied kerogen is type III kerogen originated mainly from terrestrial plant debris and aquatic organic matter. The expected generated HC is mainly gas. The studied Salam-1X samples are poor to good organic richness, with poor to good source potiental. The studied samples are marginally mature to mature thermal maturation reaching the stage oil generation. The kerogen type is a mixture of type III/II kerogen derived mainly from mixed organic sources.","PeriodicalId":7687,"journal":{"name":"Al-Azhar Bulletin of Science","volume":"44 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83571281","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-06-09DOI: 10.21608/absb.2019.67883
Fouad Abdel Hamid, M. Sarhan, M. Younes, M. Saleh
The taxonomic identity of canids of the genus Canis in North Africa has been investigated using molecular phylogenetic analysis based on Cytochrome b mitochondrial DNA sequence analysis. Tissue samples from 18 Canis specimens collected from all known populations/taxa in Egypt were obtained and analyzed. The resulting Cyt b mt DNA sequences of current Canis taxa, described based morphological characters were compared to each other and to other Canis populations/taxa across North Africa and the Middle East. The results showed no detectable sequence differentiation among all populations, suggesting that the separation of the phenotypically differentiated populations of Egypt has been relatively recent. Estimate divergence time between different phylogroups of the genus and the phylogeographic history of the genus was discussed in a regional paleogeographic context.
采用基于细胞色素b线粒体DNA序列分析的分子系统发育分析方法，对北非犬科动物进行了分类鉴定。从埃及所有已知种群/分类群中收集的18只犬标本进行组织样本分析。基于形态特征描述的现有犬类分类群的Cyt b mt DNA序列相互比较，并与北非和中东的其他犬类种群/分类群进行比较。结果显示，在所有种群中没有可检测到的序列分化，这表明埃及表型分化种群的分离是相对较近的。在区域古地理背景下讨论了该属不同系群之间的分化时间估计和该属的系地理历史。
{"title":"MOLECULAR PHYLOGENETIC RELATIONS OF MAMMALS OF THE GENUS CANIS IN EGYPT","authors":"Fouad Abdel Hamid, M. Sarhan, M. Younes, M. Saleh","doi":"10.21608/absb.2019.67883","DOIUrl":"https://doi.org/10.21608/absb.2019.67883","url":null,"abstract":"The taxonomic identity of canids of the genus Canis in North Africa has been investigated using molecular phylogenetic analysis based on Cytochrome b mitochondrial DNA sequence analysis. Tissue samples from 18 Canis specimens collected from all known populations/taxa in Egypt were obtained and analyzed. The resulting Cyt b mt DNA sequences of current Canis taxa, described based morphological characters were compared to each other and to other Canis populations/taxa across North Africa and the Middle East. The results showed no detectable sequence differentiation among all populations, suggesting that the separation of the phenotypically differentiated populations of Egypt has been relatively recent. Estimate divergence time between different phylogroups of the genus and the phylogeographic history of the genus was discussed in a regional paleogeographic context.","PeriodicalId":7687,"journal":{"name":"Al-Azhar Bulletin of Science","volume":"43 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90392097","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-06-03DOI: 10.21608/absb.2019.67879
H. Shousha, M. Atta, A. Bakhit, H. Diab, A. A. E. Hagg, Samah Dahy
Natural radioactivity of 238U, 232Th series and 40K of black sand samples collected along El-Fanar and El-Nargess Beaches in Baltim area, north of the Nile Delta in Kafr El-Sheikh Governorate, were measured using a gamma-ray spectrometer with a high purity germanium (HPGe) detector. Results showed that the average activity concentrations of 238U and 232Th in El-Fanar Beach was significantly higher (73.22±5.1 and 70.8 ± 4.9 Bq kg-1) than El-Nargess Beach (31.91±2.2 and 25.95 ±1.8 Bq kg-1) respectively. The average activity concentrations of 40K in El-Fanar Beach was lower (67.47±4.7 Bq kg-1) than that in El-Nargess Beach (80.75±5.6 Bq kg-1). The hazard indices due to these radionuclides have been calculated. The obtained results from this study indicate that the average activity concentrations of 238U, 232Th and40K at El-Nargess Beach are within world median ranges while average activities of 238U and232Th in El-Fanar Beach are higher than the world mean (33and45) Bq kg-1 respectively. This study aimed to establish a baseline map of radioactivity background levels in the aforementioned region to assess any change in the radiological background levels due to any artificial effects attributed to any radiation activities.
{"title":"NATURAL RADIOACTIVITY ASSESSMENT AND THE ASSOCIATED RADIOLOGICAL HAZARDS FOR BEACH SAND, BALTIM AREA, EGYPT.","authors":"H. Shousha, M. Atta, A. Bakhit, H. Diab, A. A. E. Hagg, Samah Dahy","doi":"10.21608/absb.2019.67879","DOIUrl":"https://doi.org/10.21608/absb.2019.67879","url":null,"abstract":"Natural radioactivity of 238U, 232Th series and 40K of black sand samples collected along El-Fanar and El-Nargess Beaches in Baltim area, north of the Nile Delta in Kafr El-Sheikh Governorate, were measured using a gamma-ray spectrometer with a high purity germanium (HPGe) detector. Results showed that the average activity concentrations of 238U and 232Th in El-Fanar Beach was significantly higher (73.22±5.1 and 70.8 ± 4.9 Bq kg-1) than El-Nargess Beach (31.91±2.2 and 25.95 ±1.8 Bq kg-1) respectively. The average activity concentrations of 40K in El-Fanar Beach was lower (67.47±4.7 Bq kg-1) than that in El-Nargess Beach (80.75±5.6 Bq kg-1). The hazard indices due to these radionuclides have been calculated. The obtained results from this study indicate that the average activity concentrations of 238U, 232Th and40K at El-Nargess Beach are within world median ranges while average activities of 238U and232Th in El-Fanar Beach are higher than the world mean (33and45) Bq kg-1 respectively. This study aimed to establish a baseline map of radioactivity background levels in the aforementioned region to assess any change in the radiological background levels due to any artificial effects attributed to any radiation activities.","PeriodicalId":7687,"journal":{"name":"Al-Azhar Bulletin of Science","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83451384","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-06-01DOI: 10.21608/absb.2019.67880
N. Kotb, M. Tohamy, A. Solieman, T. E. Zakla, T. Z. Amer, S. Elmeniawi, M. Comsan
The aim of the study is to characterize 241Am-Be isotopic neutron source with 5 Ci activity and nominal neutron yield 1.1×107 n/s. The emitted neutrons were measured employing threshold multi-foil activation technique using the following reactions: 115In(n,n'), 58Ni(n,p), 64Zn(n,p), 27Al(n,p), 56Fe(n,p), 59Co(n,α), 24Mg(n,p), and27Al(n,α). The threshold reactions were selected based on their half-lives, adequate threshold energy and cross-section. The reaction rate of each sample foil is measured by detecting the gamma ray spectra produced as a result of reaction products decay. A hyper pure germanium detector (HPGe) is used for gamma-ray spectrum measurements. The obtained spectra were analyzed using Genie2000 software and the associated system absolute efficiency was calculated using Efftran software. Obtained reaction rates were compared with available published data.
{"title":"CHARACTERIZATION OF 241AM-BE NEUTRON SOURCE USING THRESHOLD FOIL ACTIVATION TECHNIQUE","authors":"N. Kotb, M. Tohamy, A. Solieman, T. E. Zakla, T. Z. Amer, S. Elmeniawi, M. Comsan","doi":"10.21608/absb.2019.67880","DOIUrl":"https://doi.org/10.21608/absb.2019.67880","url":null,"abstract":"The aim of the study is to characterize 241Am-Be isotopic neutron source with 5 Ci activity and nominal neutron yield 1.1×107 n/s. The emitted neutrons were measured employing threshold multi-foil activation technique using the following reactions: 115In(n,n'), 58Ni(n,p), 64Zn(n,p), 27Al(n,p), 56Fe(n,p), 59Co(n,α), 24Mg(n,p), and27Al(n,α). The threshold reactions were selected based on their half-lives, adequate threshold energy and cross-section. The reaction rate of each sample foil is measured by detecting the gamma ray spectra produced as a result of reaction products decay. A hyper pure germanium detector (HPGe) is used for gamma-ray spectrum measurements. The obtained spectra were analyzed using Genie2000 software and the associated system absolute efficiency was calculated using Efftran software. Obtained reaction rates were compared with available published data.","PeriodicalId":7687,"journal":{"name":"Al-Azhar Bulletin of Science","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74539882","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-06-01DOI: 10.21608/absb.2019.66072
M. E. Awad, I. A. Hassan, H. Dewdar, A. Saad
A several types of forces are acting on the satellite. These forces are classified into conservative and nonconservativeforce. The main concern in the present research work is to studding the effect of conservative forces on the satellite orbital motion and represent this effect on satellite ground track. Where the ground tracks are the locus of points formed by the points on the Earth directly below a satellite as it travels in orbit. A mathematical model and a program code is designed using Matlab package to calculate the perturbed ground track under J2 and luni-solar forces. Whereas the J2 and Luni-Solar are a conservative forces, the secular variation is presented only in RAAN and . Otherwise the remaining orbital element is varies periodically. The perturbed ground track is calculated under the effect of J2 and luni-solar forces. The perturbed position vectors for a satellite are converted to its corresponding latitudes and longitudes. The satellite’s position in one revolution is displayed to represent where the satellite at the time desired.
{"title":"PERTURBED GROUND TRACK UNDER THE INFLUENCE OF J2 AND LUNISOLAR FORCES","authors":"M. E. Awad, I. A. Hassan, H. Dewdar, A. Saad","doi":"10.21608/absb.2019.66072","DOIUrl":"https://doi.org/10.21608/absb.2019.66072","url":null,"abstract":"A several types of forces are acting on the satellite. These forces are classified into conservative and nonconservativeforce. The main concern in the present research work is to studding the effect of conservative forces on the satellite orbital motion and represent this effect on satellite ground track. Where the ground tracks are the locus of points formed by the points on the Earth directly below a satellite as it travels in orbit. A mathematical model and a program code is designed using Matlab package to calculate the perturbed ground track under J2 and luni-solar forces. Whereas the J2 and Luni-Solar are a conservative forces, the secular variation is presented only in RAAN and . Otherwise the remaining orbital element is varies periodically. The perturbed ground track is calculated under the effect of J2 and luni-solar forces. The perturbed position vectors for a satellite are converted to its corresponding latitudes and longitudes. The satellite’s position in one revolution is displayed to represent where the satellite at the time desired.","PeriodicalId":7687,"journal":{"name":"Al-Azhar Bulletin of Science","volume":"30 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75311280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-06-01DOI: 10.21608/absb.2019.67893
E. M. Elnaggar, T. Elsokkary, Mostafa A. Shohide, Basil A. El Sabbagh
Nanomaterials have an important role for enhancingthe concrete properties and inhibition of rebar corrosion in reinforced concrete. Nanosilica (NS) is one of the most effective cementitious materials, which possess high pozzolanic nature. In this work, NS was added in mix design of concrete with different ratios as; 0, 0.5, 1, 1.5, 2and 2.5 % by weight of Portland cement. Physical, mechanical properties (workability, density) were determinedfor the fresh concrete samples. While, compressive strength andmicrostructural properties of the interfacial transition zone (ITZ) between cement pastes and aggregates of concrete were investigatedfor the hardened samples.As well as electrochemical measurements (open circuit potential and linear polarization) were done for the reinforced concrete samples. The results show that, concretes containing NS up to 2% have a higher compressive strength and a denser in interfacial transition zone (ITZ). Also, corrosion inhibition for reinforced concrete increased gradually by increasing NS addition up to 2%.
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