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Thesis
Abd El Baset, Walaa Abd El Hakeem
615 علم الصيدلة والعلاج   615.9 علم السموم  
Effect of weather factors on population density of aphid and the ladybird as a major natural enemy - Seasonal abundance of careal aphids and their associated natural enemies - Survey of aphids infesting wheat plant and their associated natural enemies - preferability of an aphid species - Rhopalosiphum padi on some wheat cultivars - i.e. susceptibity test

Thesis 2016
حسن’ مروه حسين على .
547 الكيمياء العضوية  
This thesis is devoted to calculation the energy eigenvalues of the channeled positrons through single wall carbon nanotubes (n - m). According to the continuum model approximation given by Lindhard for the case of an axial channeling in single crystals - the actual periodic potential of a row of atoms is replaced by a potential averaged over a direction parallel to the row - called continuum potential. The calculations were executed by using the atomic interaction potential as given by Moliere potential and Biersack’s universal potential. The maximum number of bound states and the energy eigenvalues were calculated for positrons of 100 MeV energy incident in a direction parallel to the nanotube axis - by using WKB method. The calculations showed that the estimation of the maximum number of bound states of the channeled positron in armchair - chiral - and zigzag nanotubes is higher for the Moliere potential than for the Universal potential. The calculations showed that the effect of temperature by using Debye approximation of thermal vibration amplitude on the channeling potential is very small and gave the same eigenvalues and the same number of bound states as that for the static nanotubes.
Also - the channeling radiation characteristics of positrons channeled in single-walled carbon nanotubes (SWCNTs) were estimated. The channeled positrons move along the nanotube axis - (z-axis) - with energies (10-500) MeV. This thesis covers SWCNTs with different chiral indices (n - m). The energy eigenvalues - in a plane normal to the nanotube axis (xy-plane) - of relativistic positron channeled through SWCNTs has been used to calculate the emitted photon energy in the forward direction - i.e - channeling radiation. Also - the calculations covered both the wave length of the emitted radiation and the maximum number of bound states of the channeled positrons as a function of the nanotube radius at different incident energies. The results of the calculations showed that - in this energy range - the emitted radiation energy lies in the X-ray band and as the energy of the incident positron increases - the emitted radiation energy increases towards the γ- energy band and accordingly - the wave length decrease towards the γ-band for the same transition . For all values of positron energy - the wave length of the emitted radiation was found to be a decreasing function of the nanotube radius while the maximum number of bound states of the channeled positrons is an increasing function of the nanotube radius for the different types of SWCNTs namely - zigzag - armchair and chiral.

Articles
m., sharaf.
620 الهندسة   620 الهندسة  
mechanical engineering - mechanical power - .software design
Journal of Engineering Sciences / ,Journal of Engineering Sciences /
vol. 27, no. 2 (july 1999) ,vol. 27, no. 2 (july 1999) / P. 1 – 290 :

Thesis 2012
Ziada,Hisham Fahmy Mohamed
616 الأمراض  
Hisham Fahmy Mohamed Ziada
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Thesis 2010
SHAFIE,WAFAA WAHBA MOHAMED
633 المحاصيل الحقلية والنباتية  
Wafaa Wahba Mohamed Shafie: Analysis of Gene Action for Yield and Quality characteristics in Diallel Crosses of Sesame. Unpublished Ph.D. Thesis - Department of Agronomy - Faculty of Agriculture - Ain Shams University - 2010. br Eight sesame genotypes were crossed in a diallel mating design - excluding reciprocals - to produce 28 F1 hybrid seeds in 2004 season and the 36 entries (8 parents + 28 F1’ s) were evaluated for eleven traits in 2005 season. The eight genotypes were re-crossed in the same diallel pattern in 2005 season and the 36 entries were evaluated for the same traits in 2006 season aiming to study heterosis - combing abilities - types of gene action and heritability - as well as correlation and path coefficient analysis for earliness - yield attributes and oil and protein contents in both seasons. br The results indicated that the mean squares due to all 36 genotypes as well as mean squares due to parents and crosses were highly significant for all studied characters - i.e - days to flowering - height of first capsule - plant height - fruiting zone length - number of fruiting branches/pant - number of capsules/plant - capsule length - 1000-seed weight - seed yield/plant - oil and protein percentages in both seasons - revealing the presence of sufficient genetic variability in the studied genotypes. br Parents vs. crosses mean squares as an indication to average heterosis for all hybrids were significant in all traits. Significant desirable negative or positive heteosis relative to mid and better parents were observed in many crosses for all traits in both seasons. br Both general and specific combining ability mean squares were found to be highly significant for all studied traits in both seasons - indicating the importance of both additive and non-additive gene effects in the expression of the studied traits. The ratios of GCA/SCA variances were greater than unity for days to flowering in the first season and near unity in the 2nd - height of first capsule - plant height - fruiting zone length - no. of fruiting branches - no. of capsules/plant - capsule length - 1000-seed weight - seed yield/plant - oil % and protein % in both seasons - indicating that the inheritance of these traits were mainly controlled by additive gene effects. However - ratios were less than unity for no. of capsules/plant in both seasons illustrating that this traits was mainly controlled by the non-additive gene effects. Good general combiner parents were identified for each of the studied traits. Some crosses exhibited significant desirable SCA effects in all studied traits and some of them involved at least one good general combiner parent - therefore - considered as promising F1 cross combinations for improving sesame traits. br High estimates of heritability values in the narrow sense exceeding 50% were detected for plant height - number of branches/plant - fruiting zone length - oil% and protein% in the two seasons. These values ranged -#102;-#114;-#111;-#109; 50.04% for number of branches/plant in 2005 season to 66.04% for oil % in 2006 season - indicating the importance of additive and additive x additive gene effects in the inheritance of these traits and consequently the effectiveness of selection for improving such traits in early segregating generations. However - moderate values of heritability in the narrow sense were obtained in both seasons for number of capsules/plant - capsule length - 1000-seed weight and seed yield/plant - ranging -#102;-#114;-#111;-#109; 32.67% for 1000-seed weight in the 1st season to 45.63% for seed yield/plant in the 2nd. With regard to the two earliness traits - i.e. days to flowering and height of first capsule - low estimates of narrow sense heritability were obtained in both seasons ranging -#102;-#114;-#111;-#109; 21.24% for days to flowering in the 2nd season to 27.49% for height of first capsule in the 2nd season - indicating that - in the case of moderate and low heritabilities in the narrow sense - response to selection for these traits in later segregating generations would be expected. br Except for oil% - the other 10 earliness - yield attributes and protein content exhibited consistent high estimates of broad sense heritabilities as compared to their respective narrow sense values ranging -#102;-#114;-#111;-#109; 84.6% for 1000-seed weight in 2005 season to 99.4% for height of first capsule in both seasons - indicating that dominance effects had prominent role in the inheritance of these traits. br Path analysis indicated that - plant height - fruiting zone length - height of first capsule and no. of capsules/plant and their interactions a crosse as the main sources of seed yield variation br . br Key Words: Sesame - Diallel crosses - Combining abilities - Heritability - Earliness - Yield - Oil - Protein - Correlation and path analysis. br Heterosis estimates - Wafaa Wahba Mohamed Shafie: Analysis of Gene Action for Yield and Quality Characteristics in Diallel Crosses of Sesame. Unpublished Ph.D. Thesis - Department of Agronomy - Faculty of Agriculture - Ain Shams University - 2010.
Eight sesame genotypes were crossed in a diallel mating design - excluding reciprocals - to produce 28 F1 hybrid seeds in 2004 season and the 36 entries (8 parents + 28 F1’ s) were evaluated for eleven traits in 2005 season. The eight genotypes were re-crossed in the same diallel pattern in 2005 season and the 36 entries were evaluated for the same traits in 2006 season aiming to study heterosis - combing abilities - types of gene action and heritability - as well as correlation and path coefficient analysis for earliness - yield attributes and oil and protein contents in both seasons.
The results indicated that the mean squares due to all 36 genotypes as well as mean squares due to parents and crosses were highly significant for all studied characters - i.e - days to flowering - height of first capsule - plant height - fruiting zone length - number of fruiting branches/pant - number of capsules/plant - capsule length - 1000-seed weight - seed yield/plant - oil and protein percentages in both seasons - revealing the presence of sufficient genetic variability in the studied genotypes.
Parents vs. crosses mean squares as an indication to average heterosis for all hybrids were significant in all traits. Significant desirable negative or positive heteosis relative to mid and better parents were observed in many crosses for all traits in both seasons.
Both general and specific combining ability mean squares were found to be highly significant for all studied traits in both seasons - indicating the importance of both additive and non-additive gene effects in the expression of the studied traits. The ratios of GCA/SCA variances were greater than unity for days to flowering in the first season and near unity in the 2nd - height of first capsule - plant height - fruiting zone length - no. of fruiting branches - no. of capsules/plant - capsule length - 1000-seed weight - seed yield/plant - oil % and protein % in both seasons - indicating that the inheritance of these traits were mainly controlled by additive gene effects. However - ratios were less than unity for no. of capsules/plant in both seasons illustrating that this traits was mainly controlled by the non-additive gene effects. Good general combiner parents were identified for each of the studied traits. Some crosses exhibited significant desirable SCA effects in all studied traits and some of them involved at least one good general combiner parent - therefore - considered as promising F1 cross combinations for improving sesame traits.
High estimates of heritability values in the narrow sense exceeding 50% were detected for plant height - number of branches/plant - fruiting zone length - oil% and protein% in the two seasons. These values ranged from 50.04% for number of branches/plant in 2005 season to 66.04% for oil % in 2006 season - indicating the importance of additive and additive x additive gene effects in the inheritance of these traits and consequently the effectiveness of selection for improving such traits in early segregating generations. However - moderate values of heritability in the narrow sense were obtained in both seasons for number of capsules/plant - capsule length - 1000-seed weight and seed yield/plant - ranging from 32.67% for 1000-seed weight in the 1st season to 45.63% for seed yield/plant in the 2nd. With regard to the two earliness traits - i.e. days to flowering and height of first capsule - low estimates of narrow sense heritability were obtained in both seasons ranging from 21.24% for days to flowering in the 2nd season to 27.49% for height of first capsule in the 2nd season - indicating that - in the case of moderate and low heritabilities in the narrow sense - response to selection for these traits in later segregating generations would be expected.
Except for oil% - the other 10 earliness - yield attributes and protein content exhibited consistent high estimates of broad sense heritabilities as compared to their respective narrow sense values ranging from 84.6% for 1000-seed weight in 2005 season to 99.4% for height of first capsule in both seasons - indicating that dominance effects had prominent role in the inheritance of these traits.
Path analysis indicated that - plant height - fruiting zone length - height of first capsule and no. of capsules/plant and their interactions a crosse as the main sources of seed yield variation
.
Key Words: Sesame - Diallel crosses - Combining abilities - Heritability - Earliness - Yield - Oil - Protein - Correlation and path analysis.
Heterosis estimates
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