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.

Determining Dimensions of Job Satisfaction among Employees: Evidence from Commercial Bank Industries in Bangladesh

Md. Sayed UDDIN(Md. Sayed UDDIN ),Md. Atikur RAHAMAN(Md. Atikur RAHAMAN ),Wasib Bin LATIF(Wasib Bin LATIF ) 한국유통과학회 2023 The Journal of Asian Finance, Economics and Busine Vol.10 No.2

Since the banking industry relies so heavily on strong customer-staff interactions, measuring employee job satisfaction has become a critical problem. To achieve benefits for both individuals and organizations, it is crucial to foster and ensure employee job satisfaction. The main objective of this study is to determine the influencing factors of employees’ job satisfaction in commercial banks in Bangladesh. This study focused on some significant factors such as employee empowerment, job security, management support, and attractive compensation in an organization. In terms of research purpose, non-probability convenience sampling has been used, and the study is quantitative in nature. For data collection purposes, an online survey questionnaire was prepared based on previously published articles. The targeted population was the bank employees of commercial banks in Bangladesh where the final sample size was n = 200. For analyzing the collected data, SPSS 26.0 version has been used to test the study model and the proposed hypotheses. This study also shows that employee empowerment, job security, management support, and attractive compensation have positive and significant effects on employees’ job satisfaction at the workplace. Finally, this study has offered some extraordinary directions and implications for future research on commercial bank authorities in Bangladesh.

Alleviation of salt stress in  Triticum aestivum by biopriming with  Phanerochaete chrysosporium

Hanan El-Sayed Dief,El-Sayed A. Hashem,Salwa Fawzan,Ashraf S. A. El-Sayed 한국작물학회 2021 Journal of crop science and biotechnology Vol.24 No.1

Wheat is one of the most important cereals, vital basic crop in Egypt, covering approximately 32.6% of the total winter land. However, sensitivity to abiotic stress especially salinity is one the major current hurdles that reduce the global yield of this crop. Plant biopriming with fungi is the recent technology that might alleviate the salt stress eff ect. Thus, the objective of this work was to examine the eff ect of Triticum aestivum grains biopriming with Phanerochaete chrysosporium on the response of wheat to salt stress. From the physiological and biochemical parameters, biopriming of wheat grains with P. chrysosporium significantly alleviates the salt stress and markedly increases the growth parameters, photosynthetic pigments and osmolytes (soluble sugars, soluble protein and proline) contents. In addition, it alleviates the oxidative damage, as indicated by the lower accumulation of malondealdehyde and increasing the activity of antioxidant enzymes; superoxide dismutase, catalase, and ascorbate peroxidase in wheat seedlings. Results indicate the potential of using P. chrysosporium biopriming for reducing the deteriorating eff ects of salinity.

Separation axioms in (L,M)-fuzzy topology (L,M)-fuzzy convexity spaces

Osama Rashed Sayed,EL-Sayed EL-Sanousy,Yaser Hassanein Ragheb Sayed 원광대학교 기초자연과학연구소 2021 ANNALS OF FUZZY MATHEMATICS AND INFORMATICS Vol.21 No.1

In this paper, we dene r-L-fuzzy closed convex sets and r-L-fuzzy closed neighbourhoods in an (L, M)-fuzzy topology (L, M)-fuzzy convexity spaces. Also, r-L-fuzzy neighbourhood separation properties r- L-FNSi were studied where i = f0, 1, 2, 3, 4g. In addition, we also study the invariance or otherwise of these separation properties under subspace and product.

Bisphosphonate’s effect on the tongue in adult male albino rats and the possible protective role of rutin: light and scanning electron microscopic study

Dalia El-sayed El-ghazouly(Dalia El-sayed El-ghazouly ),Rania Ibrahim Yassien(Rania Ibrahim Yassien ) 대한해부학회 2024 Anatomy & Cell Biology Vol.57 No.1

Alendronate sodium (ALS) is a nitrogen-containing bisphosphonate used for the treatment of different bone disorders. However, its adverse effect on oral soft tissue has been detected. Rutin (RUT) is natural flavonoid with antioxidant and anti-inflammatory properties. This work aimed to investigate the possible effect of ALS on the tongue of adult male albino rats and to evaluate the possible protective role of RUT. Forty adult male albino rats were equally divided into four groups: group I (control), group II (RUT): Received RUT 50 mg/kg, group III (ALS): Received ALS 1 mg/kg, group IV (ALS+RUT): Received ALS and RUT with the same doses as pervious groups. The drugs were given once daily for 5 weeks. Tongue specimens were taken and processed for light and scanning electron microscopic inspection. ALS treated group revealed structural changes in the tongue in the form of decrease in the height of the filiform papillae with blunt ends, marked atrophy in some papillae with areas of focal loss, loss of some epithelial cells, pyknotic nuclei and cytoplasmic vacuoles in some epithelial cells. The lamina propria showed inflammatory cellular infiltration with congested blood vessels. Statistically, there were highly significant decrease in the number of proliferating cell nuclear antigen immunopositive cells, area percentage of Bcl-2 immunoexpression and highly significant increase in the collagen content compared to control group. Administration of RUT with ALS minimizes these changes. RUT protected the rat tongue against the histological and immunohistochemical changes induced by ALS through its antioxidant and anti-inflammatory properties.

Tailoring the separation performance and antifouling property of polyethersulfone based NF membrane by incorporating hydrophilic CuO nanoparticles

Sayed Mohsen Hosseini,Fatemeh Karami,Samaneh Koudzari Farahani,Samaneh Bandehali,Jiangnan Shen,Ehsan Bagheripour,Amin Seidypoor 한국화학공학회 2020 Korean Journal of Chemical Engineering Vol.37 No.5

CuO/PES composite membranes were fabricated through phase inversion method, focusing on fouling reduction and improving separation performance. Copper oxide nanoparticles were used as filler additive in the membrane structure. The effect of the embedded CuO nanoparticles on the morphology was studied by considering SEM, SOM and 3D surface images. Flux recovery ratio (FRR%), water contact angle, water content, mechanical tensile strength, porosity and mean pore size, salt rejection and water flux were investigated to evaluate the performance of fabricated membranes. The SOM images showed a uniform surface for the modified membranes. SEM images showed a finger-like structure for the modified membranes. Results also denoted an increment in porosity and mean pore size of membrane at low concentration of CuO NPs, whereas the opposite trend was found at higher concentration of nanoparticles. Utilizing CuO NPs enhanced the membrane tensile strength obviously. PWF significantly was improved by applying CuO NPs in membrane matrix. Highest PWF (42.63 L/m2h) was observed for PES-0.05 wt% CuO blended membrane, whereas it was 10.41 (L/ m2h) for pristine ones. Salt rejection also measured 82% for virgin membrane and 63-90% for modified membranes. Moreover, FRR% were measured (~77% to ~93%), while the pristine membrane showed ~63% FRR%.

An edible vaccine development for coronavirus disease 2019: the concept

Sayed Sartaj Sohrab 대한백신학회 2020 Clinical and Experimental Vaccine Research Vol.9 No.2

A novel coronavirus was emerged in December 2019 from Wuhan city, China and has now become a global threat to human health. Currently, the coronavirus disease 2019 (COVID-19) has spread to more than 34 countries with 2,445 deaths and 78,811 confirmed cases. Currently, there is no vaccine available against COVID-19. The traditional vaccines development requires more time and high cost and due to this, the disease outbreaks becomes more challenging. Now a days, plants have become more attractive platform for edible vaccine production than the other system. The development of an edible vaccine in a selected plant system has many significant advantages such as; easy and efficient oral delivery, low cost with higher scale production, avoidance of any trained medical personnel for delivery, lack of any pathogenic infection, multicomponent expression in a single plant, and so forth. In this manuscript, the concept, development, and importance of an edible vaccine have been discussed. By using this plant-based platform, an edible vaccines can be produced in many crops like banana, cucumber, carrot, lettuce, and tomato against various diseases. Due to increasing cases globally with COVID-19, there is an urgent requirement to develop an ideal vaccine and antiviral therapy against this virus to control the disease worldwide.

Dembo polymerase chain reaction technique for detection of bovine abortion, diarrhea, and respiratory disease complex infectious agents in potential vectors and reservoirs

Sayed Samim Rahpaya,Shinobu Tsuchiaka,Mai Kishimoto,Mami Oba,Yukie Katayama,Yuka Nunomura,Saki Kokawa,Takashi Kimura,Atsushi Kobayashi,Yumi Kirino,Tamaki Okabayashi,Nariaki Nonaka,Hirohisa Mekata,Hiro 대한수의학회 2018 Journal of Veterinary Science Vol.19 No.3

Bovine abortion, diarrhea, and respiratory disease complexes, caused by infectious agents, result in high and significant economic losses for the cattle industry. These pathogens are likely transmitted by various vectors and reservoirs including insects, birds, and rodents. However, experimental data supporting this possibility are scarce. We collected 117 samples and screened them for 44 bovine abortive, diarrheal, and respiratory disease complex pathogens by using Dembo polymerase chain reaction (PCR), which is based on TaqMan real-time PCR. Fifty-seven samples were positive for at least one pathogen, including bovine viral diarrhea virus, bovine enterovirus, Salmonella enterica ser. Dublin, Salmonella enterica ser. Typhimurium, and Neospora caninum; some samples were positive for multiple pathogens. Bovine viral diarrhea virus and bovine enterovirus were the most frequently detected pathogens, especially in flies, suggesting an important role of flies in the transmission of these viruses. Additionally, we detected the N. caninum genome from a cockroach sample for the first time. Our data suggest that insects (particularly flies), birds, and rodents are potential vectors and reservoirs of abortion, diarrhea, and respiratory infectious agents, and that they may transmit more than one pathogen at the same time.

Application of SWAT to estimate runoff and sediment yield of Salma Dam watershed in Afghanistan

( Sayed Shajahan Sadiqi ),남원호 ( Won-ho Nam ),홍은미 ( Eun-mi Hong ) 한국농공학회 2019 한국농공학회 학술대회초록집 Vol.2019 No.-

Sediments are a principal component in water resource projects for dam sedimentation, soil and water conservation, and design of efficient erosion control structures. High sediment rates lead to filling dam and loss of live storage of dam, which is eventually commanding to loss of production potential and evacuation of sediments from the dam is a costly process that can have large environmental impacts. A physically-based distributed hydrological model, SWAT (Soil and Water Assessment Tool), was used to estimate of runoff and sediment yield in the outlet of Salma Dam watershed in Harirud river basin measuring of 11,550㎢ catchment area. The main objectives of the study were to analyze the sediment yield in the outlet of the catchment and effect of LULC (Land Use and Land Cover) changes on sediment yield and flow values. The basin shows large heterogeneity in term of a hydrogeological parameter, LULC and soil features. The model was calibrated and validated using observed runoff and sediment yield data of 10 years (2008-2018) at the basin outlet. The average values for RSR (RMSE-observations standard deviation ratio) and NSE (Nash-Sutcliffe efficiency) for sediment are found to be 0.60 and 0.61, for runoff are found to be 0.67 and 0.64, which are within good limits for sediment and a good limit for runoff respectively. The overall average annual output for sediment at the outlet point was estimated 133.02 Met ton/month, is model monthly output. In general, the model was capable of simulating runoff and sediment in Salam dam watershed. As land development is a continuous process, for the optimum use of the land cover and water resources of the area, it is recommended that soil and watershed conservation practice should be undertaken in order to keep the sustainability of the reservoir conserving sediment reduction.

High surface area-activated carbon from Glycyrrhiza glabra residue by ZnCl2 activation for removal of Pb(II) and Ni(II) from water samples

Sayed Zia Mohammadi,Hooshang Hamidian,Zahra Moeinadini 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.6

A high-surface-area activated carbon was prepared by chemical activation of Glycyrrhiza glabra residuewith ZnCl2 as active agent. Then, the adsorption behavior of Pb(II) and Ni(II) ion onto produced activatedcarbon has been studied. The experimental data were fitted to various isotherm models. According toLangmuir model, the maximum adsorption capacity of Pb(II) and Ni(II) ions were found to be 200 and166.7 mg g-1, respectively, at room temperature. Kinetic studies showed the adsorption processfollowed pseudo second-order rate model. High values of intra-particle rate constants calculated showsthe high tendency of activated carbon for removal of Pb(II) and Ni(II) ions.