Nonlinear transient analysis of FG pipe subjected to internal pressure and unsteady temperature in a natural gas facility

Soliman, Ahmed E.,Eltaher, Mohamed A.,Attia, Mohamed A.,Alshorbagy, Amal E. Techno-Press 2018 Structural Engineering and Mechanics, An Int'l Jou Vol.66 No.1

This study investigates the response of functionally graded (FG) gas pipe under unsteady internal pressure and temperature. The pipe is proposed to be manufactured from FGMs rather than custom carbon steel, to reduce the erosion, corrosion, pressure surge and temperature variation effects caused by conveying of gases. The distribution of material graduations are obeying power and sigmoidal functions varying with the pipe thickness. The sigmoidal distribution is proposed for the 1st time in analysis of FG pipe structure. A Two-dimensional (2D) plane strain problem is proposed to model the pipe cross-section. The Fourier law is applied to describe the heat flux and temperature variation through the pipe thickness. The time variation of internal pressure is described by using exponential-harmonic function. The proposed problem is solved numerically by a two-dimensional (2D) plane strain finite element ABAQUS software. Nine-node isoparametric element is selected. The proposed model is verified with published results. The effects of material graduation, material function, temperature and internal pressures on the response of FG gas pipe are investigated. The coupled temperature and displacement FEM solution is used to find a solution for the stress displacement and temperature fields simultaneously because the thermal and mechanical solutions affected greatly by each other. The obtained results present the applicability of alternative FGM materials rather than classical A106Gr.B steel. According to proposed model and numerical results, the FGM pipe is more effective in natural gas application, especially in eliminating the corrosion, erosion and reduction of stresses.

Murraya koenigii (L.) Sprengel seeds and pericarps in relation to their chemical profiles: new approach for multidrug resistant Acinetobacter baumannii ventilator-associated pneumonia

El-Shiekh Riham A.,Elshimy Rana,Mandour Asmaa A.,Kassem Hanaa A. H.,Khaleel Amal E.,Alseekh Saleh,Fernie Alisdair R.,Salem Mohamed A. 한국응용생명화학회 2024 Applied Biological Chemistry (Appl Biol Chem) Vol.67 No.-

Acinetobacter baumannii is without a doubt one of the most problematic bacteria causing hospital-acquired nosocomial infections in today’s healthcare system. To solve the high prevalence of multi-drug resistant (MDR) in A. baumannii, we investigated one of the medicinal plants traditionally used as antibacterial agent; namely Murraya koenigii (L.) Sprengel. The total methanolic extracts of seeds and pericarps were prepared and their anti-bacterial activity was assessed using the agar diffusion method and minimum inhibitory concentration (MIC) was then calculated as compared to tigecycline. Then, an in-vivo murine model was established which confirmed the promising activity of M. koenigii seeds in demonstrating anti-bacterial and anti-inflammatory actions. The histopathological study of lungs, scoring of pulmonary lesions, counting of bacterial loads after infection by multi-drug resistant A. baumannii all provided evidence to support these findings. LC–MS/MS profiling coupled to molecular networking and chemometrics detected the presence of carbazole alkaloids, and coumarins as dominate metabolites of the active seed extracts. Positively correlated metabolites to antibacterial potential were 6-(2ʹ,3ʹ-dihydroxy-3-methylbutyl)- 8-prenylumbelliferone, scopoline, and 5-methoxymurrayatin. An in-silico study was also performed on the crystal structure of MurF from A. baumannii (PDB ID: 4QF5), the studied structures of the mentioned extracts revealed good docking interaction at the active site suggestive of competition with the ATP ligand. These collective findings suggest that extracts of Murraya koenigii (L.) Sprengel seed is a novel prospective for the discovery of drug candidates against infections caused by MDR A. baumannii.

Nonlinear transient analysis of FG pipe subjected to internal pressure and unsteady temperature in a natural gas facility

Ahmed E. Soliman,Mohamed A. Eltaher,Mohamed A. Attia,Amal E. Alshorbagy 국제구조공학회 2018 Structural Engineering and Mechanics, An Int'l Jou Vol.66 No.1

This study investigates the response of functionally graded (FG) gas pipe under unsteady internal pressure and temperature. The pipe is proposed to be manufactured from FGMs rather than custom carbon steel, to reduce the erosion, corrosion, pressure surge and temperature variation effects caused by conveying of gases. The distribution of material graduations are obeying power and sigmoidal functions varying with the pipe thickness. The sigmoidal distribution is proposed for the 1st time in analysis of FG pipe structure. A Two-dimensional (2D) plane strain problem is proposed to model the pipe cross-section. The Fourier law is applied to describe the heat flux and temperature variation through the pipe thickness. The time variation of internal pressure is described by using exponential-harmonic function. The proposed problem is solved numerically by a two-dimensional (2D) plane strain finite element ABAQUS software. Nine-node isoparametric element is selected. The proposed model is verified with published results. The effects of material graduation, material function, temperature and internal pressures on the response of FG gas pipe are investigated. The coupled temperature and displacement FEM solution is used to find a solution for the stress displacement and temperature fields simultaneously because the thermal and mechanical solutions affected greatly by each other. The obtained results present the applicability of alternative FGM materials rather than classical A106Gr.B steel. According to proposed model and numerical results, the FGM pipe is more effective in natural gas application, especially in eliminating the corrosion, erosion and reduction of stresses.

Mechanical behaviors of piezoelectric nonlocal nanobeam with cutouts

Mohamed A. Eltaher,Fatema-Alzahraa Omar,Azza M. Abdraboh,Waleed S. Abdalla,Amal E. Alshorbagy 국제구조공학회 2020 Smart Structures and Systems, An International Jou Vol.25 No.2

This work presents a modified continuum model to explore and investigate static and vibration behaviors of perforated piezoelectric NEMS structure. The perforated nanostructure is modeled as a thin perforated nanobeam element with Euler.Bernoulli kinematic assumptions. A size scale effect is considered by included a nonlocal constitutive equation of Eringen in differential form. Modifications of geometrical parameters of perforated nanobeams are presented in simplified forms. To satisfy the Maxwell's equation, the distribution of electric potential for the piezoelectric nanobeam model is assumed to be varied as a combination of a cosine and linear functions. Hamilton's principle is exploited to develop mathematical governing equations. Modified numerical finite model is adopted to solve the equation of motion and equilibrium equation. The proposed model is validated with previous respectable work. Numerical investigations are presented to illustrate effects of the number of perforated holes, perforation size, nonlocal parameter, boundary conditions, and external electric voltage on the electro-mechanical behaviors of piezoelectric nanobeams.

Analysis of crack occurs under unsteady pressure and temperature in a natural gas facility by applying FGM

Mohamed A. Eltaher,Mohamed A. Attia,Ahmed E. Soliman,Amal E. Alshorbagy 국제구조공학회 2018 Structural Engineering and Mechanics, An Int'l Jou Vol.66 No.1

Cracking can lead to unexpected sudden failure of normally ductile metals subjected to a tensile stress, especially at elevated temperature. This article is raised to study the application of a composite material instead of the traditional carbon steel material used in the natural gas transmission pipeline because the cracks occurs in the pipeline initiate at its internal surface which is subjected to internal high fluctuated pressure and unsteady temperature according to actual operation conditions. Functionally graded material (FGM) is proposed to benefit from the ceramics durability and its surface hardness against erosion. FGM properties are graded at the radial direction. Finite element method (FEM) is applied and solved by ABAQUS software including FORTRAN subroutines adapted for this case of study. The stress intensity factor (SIF), temperatures and stresses are discussed to obtain the optimum FGM configuration under the actual conditions of pressure and temperature. Thermoelastic analysis of a plane strain model is adopted to study SIF and material response at various crack depths.

Assessment of Some Barley Germplasms Based on RAPD Analysis and Anti-Nutritional Factors

Mohamed, Amal A.,Matter, Mohamed Ahmed,Rady, Mohamed Ramadan 한국작물학회 2010 Journal of crop science and biotechnology Vol.13 No.2

The variation among some barley germplasm (Giza 123, Giza 127, Giza 130, Desert, and Sinai) was investigated comparatively at the molecular and biochemical levels. Leaf DNAs extracted from different barley germplasm were amplified with randomly chosen primers in a Polymerase Chain Reaction (PCR) using Random Amplified Polymorphic DNA (RAPD) technique. Only five primers amplified all DNA templates among 15 primers. Primers generated a total of 112 DNA fragments ranged from 1.2 to 0.1 kbp. Out of the 112 fragments, 16 (14.29%) were polymorphic. The result indicated that fragments generated per primer, with an average of 22.4 products, where the number of polymorphic bands per primer, with an average of 3.2 polymorphic bands. In addition, the genetic variation in the anti-nutritional factors and nutrient composition of the same genotypes were determined. A wide variation in total phenolic, phytic, tannin, vicine, and saponin contents was found among these germplasm. The range of total phenolic was 3.83 to $7.50\;mg\;g^{-1}d.w$. Among all germplasm, Desert germplasm was characterized by the highest tannin content. However, saponin ranged between $5.66\;mg\;g^{-1}d.w$. (in Giza 123) to $9.21\;mg\;g^{-1}d.w$ (in Sinai) germplasm. The concentrations of the phytic acid were generally low, ranging between 0.99 to $6.78\;mg\;g^{-1}d.w$. The germplasm Desert and Sinai had the highest level of vicine, 1.89 and $1.87\;mg\;g^{-1}d.w$., respectively. The results of the molecular characterization and anti-nutritional content can be used as the starting point needed to identify the valuable Egyptian barley germplasm.

Assessment of Some Barley Germplasms Based on RAPD Analysis and Anti-nutritional Factors

Amal A. Mohamed,Mohamed Ahmed Matter,Ramadan Rady 한국작물학회 2010 Journal of crop science and biotechnology Vol.13 No.2

The variation among some barley germplasm (Giza 123, Giza 127, Giza 130, Desert, and Sinai) was investigated comparatively at the molecular and biochemical levels. Leaf DNAs extracted from different barley germplasm were amplified with randomly chosen primers in a Polymerase Chain Reaction (PCR) using Random Amplified Polymorphic DNA (RAPD) technique. Only five primers amplified all DNA templates among 15 primers. Primers generated a total of 112 DNA fragments ranged from 1.2 to 0.1 kbp. Out of the 112 fragments, 16 (14.29%) were polymorphic. The result indicated that fragments generated per primer, with an average of 22.4products, where the number of polymorphic bands per primer, with an average of 3.2 polymorphic bands. In addition, the genetic variation in the anti-nutritional factors and nutrient composition of the same genotypes were determined. A wide variation in total phenolic, phytic, tannin, vicine, and saponin contents was found among these germplasm. The range of total phenolic was 3.83 to 7.50 mg g-¹ d.w. Among all germplasm, Desert germplasm was characterized by the highest tannin content. However, saponin ranged between 5.66 mg g-¹ d.w. (in Giza 123) to 9.21 mg g-¹ d.w (in Sinai) germplasm. The concentrations of the phytic acid were generally low, ranging between 0.99 to 6.78 mg g-¹ d.w. The germplasm Desert and Sinai had the highest level of vicine, 1.89 and 1.87 mg g-¹d.w., respectively. The results of the molecular characterization and anti-nutritional content can be used as the starting point needed to identify the valuable Egyptian barley germplasm.

Analysis of crack occurs under unsteady pressure and temperature in a natural gas facility by applying FGM

Eltaher, Mohamed A.,Attia, Mohamed A.,Soliman, Ahmed E.,Alshorbagy, Amal E. Techno-Press 2018 Structural Engineering and Mechanics, An Int'l Jou Vol.66 No.1

Cracking can lead to unexpected sudden failure of normally ductile metals subjected to a tensile stress, especially at elevated temperature. This article is raised to study the application of a composite material instead of the traditional carbon steel material used in the natural gas transmission pipeline because the cracks occurs in the pipeline initiate at its internal surface which is subjected to internal high fluctuated pressure and unsteady temperature according to actual operation conditions. Functionally graded material (FGM) is proposed to benefit from the ceramics durability and its surface hardness against erosion. FGM properties are graded at the radial direction. Finite element method (FEM) is applied and solved by ABAQUS software including FORTRAN subroutines adapted for this case of study. The stress intensity factor (SIF), temperatures and stresses are discussed to obtain the optimum FGM configuration under the actual conditions of pressure and temperature. Thermoelastic analysis of a plane strain model is adopted to study SIF and material response at various crack depths.

Pathogenicity of Bacillus Strains to Cotton Seedlings and Their Effects on Some Biochemical Components of the Infected Seedlings

Aly A. Aly,Omima M. El-Mahdy,Marian M. Habeb,Abeer Elhakem,Amal A. Asran,Maryan M. Youssef,Heba I. Mohamed,Rania S. Hanafy 한국식물병리학회 2022 Plant Pathology Journal Vol.38 No.2

Pathogenicity of eight Bacillus strains to seedlings of four cotton cultivars was evaluated under greenhouse conditions. Each of the tested cultivars was individually treated with powdered inoculum of each bacterial strain. Untreated seeds were planted as control treatments in autoclaved soil. Effects of the tested strains on levels and activities of some biochemical components of the infected seedlings were also assayed. The biochemical components included total soluble sugars, total soluble proteins, total free amino acids, peroxidase, polyphenol oxidase, phenols, and lipid peroxidation. ANOVA showed that Bacillus strain (B) was a very highly significant source of variation in damping-off and dry weight. Cotton cultivar (V) was a nonsignificant source of variation in damping-off while it was a significant source of variation in dry weight. B × V interaction was a significant source of variation in damping- off and a nonsignificant source of variation in dry weight. Bacillus strain was the most important source of variation as it accounted for 59.36 and 64.99% of the explained (model) variation in damping-off and dry weight, respectively. The lack of significant correlation between levels and activities of the assayed biochemical components and incidence of damping-off clearly demonstrated that these biochemical components were not involved in the pathogenicity of the tested strains. Therefore, it was hypothesized that the pathogenicity of the tested strains could be due to the effect of cell wall degrading enzymes of pathogenic toxins. Based on the results of the present study, Bacillus strains should be considered in studying the etiology of cotton seedling damping-off.

Improvement of bearing capacity of footing on soft clay grouted with lime-silica fume mix

Fattah, Mohammed Y.,Al-Saidi, A'amal A.,Jaber, Maher M. Techno-Press 2015 Geomechanics & engineering Vol.8 No.1

In this study, lime (L), silica fume (SF), and lime-silica fume (L-SF) mix have been used for stabilizing and considering their effects on the soft clay soil. The improvement technique adopted in this study includes improving the behaviour, of a square footing over soft clay through grouting the clay with a slurry of lime-silica fume before and after installation of the footing. A grey-colored densified silica fume is used. Three percentages are used for lime (2%, 4% and 6%) and three percentages are used for silica fume (2.5%, 5%, 10%) and the optimum percentage of silica fume is mixed with the percentages of lime. Several tests are made to investigate the soil behaviour after adding the limeand silica fume. For grouting the soft clay underneath and around the footing, a 60 ml needle was used as a liquid tank of the lime-silica fume mix. Slurried silica fume typically contains 40 to 60% silica fume by mass. Four categories were studied to stabilize soft clay before and after footing construction and for each category, the effectiveness of grouting was investigated; the effect of injection hole spacing and depth of grout was investigated too. It was found that when the soft clay underneath or around a footing is injected by a slurry of lime-silica fume, an increase in the bearing capacity in the range of (6.58-88)% is obtained. The footing bearing capacity increases with increase of depth of grouting holes around the footing area due to increase in L-SF grout. The grouting near the footing to a distance of 0.5 B is more effective than grouting at a distance of 1.0 B due to shape of shear failure of soft clay around the footing.