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.

Histopathological and genetic changes proved the anti‑cancer potential of free and nano‑capsulated sinapic acid

Doaa A. Badr,Mohamed E. Amer,Wagih M. Abd‑Elhay,Mohamed S. M. Nasr,Tamer M. M. Abuamara,Harbi Ali,Aly F. Mohamed,Maha A. Youssef,Nasser S. Awwad,Yi‑Hsu Ju,Ahmed E. Fazary 한국응용생명화학회 2019 Applied Biological Chemistry (Appl Biol Chem) Vol.62 No.5

Cancer is known to be a fierce disease that causes a large percentage of the deaths worldwide. The common cancer treatments; chemotherapy, radiotherapy and surgery are known for their severe side effects; therefore scientists are working on finding solutions to reduce these drawbacks. One of these treatment systems is the sustained released drugs formulations, these systems depend on the encapsulation of the chemotherapy within an emulsifying agent, in order to obtain a slow drug release of low doses over long time intervals. In this study, the anti-cancer effects of free and encapsulated sinapic acid was tested against lung (A549), and colon (CaCo2) cancer cell lines, along with normal fibroblast cells (HFB4) as a negative control. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay was performed for IC50 evaluation, also cell cycle assay was performed to detect cell cycle arrest status and related anti-apoptotic and pro-apoptotic; Blc-2, BAX, and P53 gene profile fold changes post cellular treatment. Data recorded revealed that encapsulated SA showed a lower toxicity than the free form to both cell lines and also to the normal cells. The cell cycle analysis showed a cell cycle arrest at the G2/M phase post cell treatment with the free and encapsulated sinapic acid accompanied with up regulation of Bax and P53 and a down regulation of Blc-2 genes in both cell lines. The data suggest a promising anti-cancer and anti-proliferative potential of free and encapsulated sinapic acid. Also they show that the anti-cancer effect of free and encapsulated sinapic acid is quite close.

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.

Secreted Phosphoprotein 1 Promoter Genetic Variants Are Associated with the Response to Pegylated Interferon α Plus Ribavirin Combination Therapy in Egyptian Patients with Chronic Hepatitis C Virus Infection

( Fahmy T Ali ),( Mohamed A M Ali ),( Mayada M A Elgizawy ),( Ahmed M Elsawy ) 대한소화기학회 2015 Gut and Liver Vol.9 No.4

Background/Aims: The T-helper 1 (TH1) immune reaction is essential for the eradication of hepatitis C virus (HCV) during pegylated interferon α (PEG-IFN-α)- and ribavirin (RBV)-based therapy in chronic HCV patients. Secreted phosphoprotein 1 (SPP1) was shown to be a crucial cytokine for the initiation of a TH1 immune response. We aimed to investigate whether SPP1 single nucleotide polymorphisms (SNPs) may influence sustained virological response (SVR) rates. Methods: Two SNPs in the promoter region of SPP1 at the .443 C>T and .1748 G>A loci were genotyped in 100 patients with chronic HCV genotype 4 infection using a TaqMan SNP genotyping assay. Results: Sixty-seven patients achieved a SVR, and 33 patients showed no SVR. Patients carrying the T/T genotype at the .443 locus showed a significantly higher SVR rate than those carrying the C/T or C/C genotype (83.67% vs 50.98%, p<0.001). At the .1748 locus, the SVR rate was significantly higher in patients with the G/G genotype than in those with the A/A genotype (88.89% vs 52.63%, p=0.028) and in patients with the G/A genotype than in those with the A/A genotype (85.29% vs 52.63%, p=0.001). Conclusions: SPP1 SNPs at .443 C>T and .1748 G>A loci may be useful markers for predicting the response to PEG-IFN-α-2b plus RBV therapy in Egyptian patients with chronic HCV genotype 4 infection. (Gut Liver 2015;9:516-524)

Bioactive compounds from Withania somnifera dun and their toxicity against some piercing sucking pests

Ragab Amany,Taher Mohamed A.,El-Rafey Helmy H.,El-Rokh Ahmed Ramadan 한국응용생명화학회 2024 Applied Biological Chemistry (Appl Biol Chem) Vol.67 No.-

Piercing sucking pests are destructive to many strategic crops all over the world. Botanical pesticides can be used to control these pests. A new withanolide derivative 3 named sominone A ((20R,22R)-1α,3β,20,27-tetrahydroxywitha- 5,24-dienolide) was isolated from the alkaloid fraction of the whole plant of Withania somnifera. In addition, there are three known compounds named withasomine 1, methyl isoferulate 2, and coagulin Q 4 were also isolated. The structures of isolated compounds were identified using different spectroscopic methods such as 1D, 2D NMR, and HRESIMS spectroscopy. The alkaloid fraction and the four isolated compounds were tested for their pesticidal activity against four piercing sucking pests (Aphis craccivora Koch, Bemisia tabaci Gennadius, Nezara viridula Linnaeus, and Tetranychus urticae Koch) that attack many strategic crops under laboratory conditions, along with azadirachtin (Okios 3.2% EC) as a positive control. The results showed that the alkaloid compound (withasomine 1) was the most toxic to A. craccivora, B. tabaci, N. viridula, and T. urticae, with LC50 values of 15.44, 36.61, 85.11, and 128.28 ppm, respectively, compared with the control. Withanolide compounds had moderate effects on all tested pests. Biochemical parameters of six enzymes; α-esterase, β-esterase, chitinase, acetylcholinesterase, glutathione-S-transferase, and peroxidase of A. craccivora were estimated at the LC50 value of the most potent compound, withasomine 1 and the values were 38.83, 72.86, 31.45, 506.4, 2.62, and 251.0, respectively. The results demonstrated that all enzymes activity levels were increased compared with the control except a remarkable inhibition in AChE enzyme level was observed compared with control. Therefore, the alkaloid fraction of W. somnifera is a promising extract that contains many active compounds that can be used as a natural pesticide against many harmful pests in agriculture crops.

New ursane triterpenoids from Ficus pandurata and their binding affinity for human cannabinoid and opioid receptors

Amgad I. M. Khedr,Sabrin R. M. Ibrahim,Gamal A. Mohamed,Hany E. A. Ahmed,Amany S. Ahmad,Mahmoud A. Ramadan,Atef E. Abd El-Baky,Koji Yamada,Samir A. Ross 대한약학회 2016 Archives of Pharmacal Research Vol.39 No.7

Phytochemical investigation of Ficus pandurataHance (Moraceae) fruits has led to the isolation of two newtriterpenoids, ficupanduratin A [1b-hydroxy-3b-acetoxy-11a-methoxy-urs-12-ene] (11) and ficupanduratin B [21ahydroxy-3b-acetoxy-11a-methoxy-urs-12-ene] (17), alongwith 20 known compounds: a-amyrin acetate (1), a-amyrin(2), 3b-acetoxy-20-taraxasten-22-one (3), 3b-acetoxy-11amethoxy-olean-12-ene (4), 3b-acetoxy-11a-methoxy-12-ursene (5), 11-oxo-a-amyrin acetate (6), 11-oxo-b-amyrinacetate (7), palmitic acid (8), stigmast-4,22-diene-3,6-dione(9), stigmast-4-ene-3,6-dione (10), stigmasterol (12), b-sitosterol(13), stigmast-22-ene-3,6-dione (14), stigmastane-3,6-dione (15), 3b,21b-dihydroxy-11a-methoxy-olean-12-ene (16), 3b-hydroxy-11a-methoxyurs-12-ene (18), 6-hydroxystigmast-4,22-diene-3-one (19), 6-hydroxystigmast-4-ene-3-one (20), 11a,21a-dihydroxy-3b-acetoxy-urs-12-ene(21), and b-sitosterol-3-O-b-D-glucopyranoside (22). Compound21 is reported for the first time from a natural source. The structures of the 20 compounds were elucidated on thebasis of IR, 1D (1H and 13C), 2D (1H–1H COSY, HSQC,HMBC and NOESY) NMR and MS spectroscopic data, inaddition to comparison with literature data. The isolatedcompounds were evaluated for their anti-microbial, antimalarial,anti-leishmanial, and cytotoxic activities. In addition,their radioligand displacement affinity on opioid andcannabinoid receptors was assessed. Compounds 4, 11, and15 exhibited good affinity towards the CB2 receptor, withdisplacement values of 69.7, 62.5 and 86.5 %, respectively. Furthermore, the binding mode of the active compounds inthe active site of the CB2 cannabinoid receptors was investigatedthrough molecular modelling.

Heat transfer characteristics and entropy generation for wing-shaped-tubes with longitudinal external fins in cross-flow

Sayed Ahmed E. Sayed Ahmed,Osama M. Mesalhy,Mohamed A. Abdelatief 대한기계학회 2016 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.30 No.6

A numerical study is conducted to clarify heat transfer characteristics, effectiveness and entropy generation for a bundle of wingshaped-tubes attached to Longitudinal fins (LF) at downstream side. The air-side Re a ranged from 1.8 x 10 3 to 9.7 x 10 3 . The fin height (h f ) and fin thickness (δ) have been changed as: (2 mm ≤ h f ≤ 12 mm) and (1.5 mm ≤ δ ≤ 3.5 mm). The analysis of entropy generation is based on the principle of minimizing the rate of total entropy generation that includes the generation of entropy due to heat transfer and friction losses. The temperature field around the wing-shaped-tubes with (LF) is predicted using commercial CFD FLUENT 6.3.26 software package. Correlations of Nu a , St a , and Bejan number (Be), as well as the irreversibility distribution ratio (Φ) in terms of Re a and design parameters for the studied bundle are presented. Results indicated that, installing fins with heights from 2 to 12 mm results in an increase in Nu a from 11 to 36% comparing with that of wing-shaped tubes without fins (NOF). The highest and lowest values of effectiveness (ε) at every value of the considered Re a range are occurred at h f = 6 mm and (NOF), respectively. The wing-shaped-tubes heat exchanger with h f = 6 mm has the highest values of (ε), efficiency index (η) and area goodness factor (G a ) and also the lowest values of Φ and hence the best performance comparing with other arrangements. The minimum values of Φ are occurred at h f = 6 mm. (Be) decreases with increasing Re a for all studied h f . The heat transfer irreversibility predominates for (1800 ≤ Re a ≤ 4200) while the opposite is true for (6950 < Re a ≤ 9700). δ has negligible effect on Nu a and heat transfer irreversibility. Comparisons between the experimental and numerical results of the present study and those, previously, obtained for similar available studies showed good agreements.

DNA Binding, Antiviral Activities and Cytotoxicity of New Furochromone and Benzofuran Derivatives

Omaima Mohamed Abdelhafez,Nehad Ahmed Abedelatif,Farid A. Badria 대한약학회 2011 Archives of Pharmacal Research Vol.34 No.10

Bromination of visnagin (1) afforded 9-bromovisnagin (2) which on its alkaline hydrolysis afforded the 3-acetyl benzofuran derivative (3). The condensation of (3) with hydrazine hydrate, phenylhydrazine and/or hydroxylamine hydrochloride afforded the corresponding pyrazole derivatives (4a, b) and isoxazole derivative (4c). On the other hand, when compound 3 was condensed with some aromatic aldehydes, this yielded corresponding α, β-unsaturated keto derivatives (5a-e). Furthermore, when 1 was subjected to chlorosulfonation, the visnaginsulfonylchloride derivative 6 was afforded, which on amidation using morpholine, a sulonamido derivative (7) was obtained. Alkaline hydrolysis of the latter compound yielded 7-N-morpholinosulsamidobenzofuran (8) which was condensed with some aromatic aldehydes to yield the corresponding chalcone compounds (9a-e). Demethylation of visnagin afforded norvisnagin (10). The reaction of 10 with ethylbromoacetate in dry acetone yielded the ester benzopyran derivative (11) which reacted with hydrazine hydrate to afford the corresponding hydrazide derivative (12) and this was condensed with 3,4,5-trimethoxybenzaldehyde to give the corresponding hydrazone (13). A thaizolidinone derivative (14) was obtained by condensation of (13) with thioglycolic acid. Chloromethylation of norvisnagin afforded a 4-chloromethyl derivative (15) which reacted with different primary and secondary amines to yield the corresponding ethylamino derivative (16a, b). Moreover, mannich bases (16a, b) and (17a-c) were obtained by reacting norvisnagin with different primary and secondary amines in the presence of formalin but benzoylation of (16a, b) and (17a-c) afforded 4-oxybenzoyl derivative (18a-e). The prepared compounds were tested for their interaction with DNA; bromovisnagin 2 showed the highest affinity and compounds 6, 15, 8a, > 14, > 16b, 17a, and 16a showed moderate activity in decreasing potency. Moreover, compound 2 also was the most active as antiviral agent toward HS-I virus and compounds 6, 7, 15, 14, 16a, and 18a were found to be moderately active. CD50 of the active compounds were also measured.

Hybrid Communication Network Architectures for Monitoring Large-Scale Wind Turbine

Ahmed, Mohamed A.,Kim, Young-Chon The Korean Institute of Electrical Engineers 2013 Journal of Electrical Engineering & Technology Vol.8 No.6

Nowadays, a rapid development in wind power technologies is occurring compared with other renewable energies. This advance in technology has facilitated a new generation of wind turbines with larger capacity and higher efficiency. As the height of the turbines and the distance between turbines increases, the monitoring and control of this new generation wind turbines presents new challenges. This paper presents the architectural design, simulation, and evaluation of hybrid communication networks for a large-scale wind turbine (WT). The communication network of WT is designed based on logical node (LN) concepts of the IEC 61400-25 standard. The proposed hybrid network architectures are modeled and evaluated by OPNET. We also investigate network performance using three different technologies: Ethernet-based, WiFi-based, and ZigBee-based. Our network model is validated by analyzing the simulation results. This work contributes to the design of a reliable communication network for monitoring and controlling a wind power farms (WPF).

The Effect of using Gamma Titanium RF Electrodes on the Ablation Volume during the Radiofrequency Ablation Process

Mohammed S. Ahmed,Mohamed Tarek El-Wakad,Mohammed A. Hassan International Journal of Computer ScienceNetwork S 2023 International journal of computer science and netw Vol.23 No.2

Radiofrequency ablation (RFA) is an alternative treatment for liver cancer to the surgical intervention preferred by surgeons. However, the main challenge remains the use of RF for the ablation of large tumours (i.e., tumours with a diameter of >3 cm). For large tumours, RFA takes a large duration in the ablation process compared with surgery, which increases patient pain. Therefore, RFA for large tumours is not preferred by surgeons. The currently materials used in RF electrodes, such as the nickeltitanium alloy (nitinol), are characterized by low thermal and electrical conductivities. On the other hand, the use of materials that have high thermal and electrical conductivities, such as titanium aluminide alloy (gamma titanium), produces more thermal energy for tumours. In this paper, we developed a cool-tip RF electrode model that uses nickel-titanium alloy and replaced it with titanium aluminide alloy by using the finite element model (FEM). The aim of this paper is to study the effect of the thermal and electrical conductivities of gamma titanium on the ablation volume. Results showed that the proposed design of the electrode increased the ablation rate by 1 cm³ /minute and 6.3 cm³/10 minutes, with a decrease in the required time ablation. Finally, the proposed model reduces the ablation time and damages healthy tissue while increasing the ablation volume from 22.5% cm³ to 62.5% cm³ in ten minutes compared to recent studies.