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Analytical Solution for Peristaltic Transport of Viscous Nanofluid in an Asymmetric Channel with Full Slip and Convective Conditions

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Communications in Theoretical Physics 2017年第7期67卷 96-102页

作者： Abdelhalim ebaid Emad H. Aly K. Vajravelu Department of Mathematics Faculty of Science University of Tabuk Tabuk 71491 Saudi Arabia Department of Mathematics Faculty of Science University of Jeddah Jeddah 21589 Saudi Arabia Department of Mathematics Faculty of Education Ain Shams University Roxy 11757 Cairo Egypt Department of Mathematics Department of Mechanical Materials and Aerospace Engineering University of Central Florida Orlando FL 32816 USA

The peristaltic ttow of nanofluids is a relatively new area of research. Scientists are of the opinion that the no-slip conditions at the boundaries are no longer valid and consequently, the first and the second order slip conditions should be addressed. In this paper, the effects of slip conditions and the convective boundary conditions at the boundary walls on the peristaltic flow of a viscous nanofluid are investigated for. Also, the exact analytical solutions are obtained for the model. The obtained results are presented through graphs and discussed. The results reveal that the two slip parameters have strong effects on the temperature and the nanoparticles volume fraction profiles. Moreover, it has been seen that the temperature and nanoparticles volume fraction profiles attain certain values when the first slip condition exceeds a specified value. However, no limit value for the second slip parameter has been detected. Further, the effects of the various emerging parameters on the flow and heat transfer characteristics have been presented.

关键词： nanofluid peristaltic flow slip model convective conditions asymmetric channel

Histopathological alterations in the liver and intestine of Nile tilapia Oreochromis niloticus exposed to long-term sublethal concentrations of cadmium chloride

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Chinese Journal of Oceanology and Limnology 2015年第4期33卷 846-852页

作者： YOUNIS Elsayed ABDEL-WARITH Abdel-Wahab AL-ASGAH Nasser ebaid Hossam Department of Zoology College of Science King Saud University Department of Animal Production Faculty of Agriculture Al-Azhar University Department of Zoology College of Science El-Minia University

Fingerlings of Nile tilapia Oreochromis niloticus were exposed to 1.68, 3.36, and 5.04 mg/L cadmium(as CdCl2), which represent 10%, 20%, and 30% of their previously determined 96-h LC5 0. After exposure for 20 days, sections of the liver and intestine of treated fish were examined histologically. Histopathological changes varied from slight to severe structural modification, depending on the exposure concentration. The hepatic tissues of fish exposed to 10% LC 50 showed markedly increased vacuolation of the hepatocytes and coarse granulation of their cytoplasm. Abundant erythrocytic infiltration among the hepatocytes was observed in fish exposed to 20% LC5 0. In the intestinal tissues of fish exposed to all doses, goblet cells proliferated and were greatly increased in size, the longitudinal muscularis mucosa was disturbed and, in the crypts of the sub-mucosal layer, apoptosis increased, indicated by large numbers of degenerated nuclei. Large numbers of inflammatory cells and dilated blood vessels were observed in the intestine of the group treated with 30% LC5 0.

关键词： fish tilapia pollutant cadmium liver intestine

Exact Solution of Non-Newtonian Blood Flow with Nanoparticles through Porous Arteries:A Comparative Study

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Computers, Materials & Continua 2020年第6期63卷 1143-1157页

作者： Wafaa Alharbi Abdulrahman Aljohani Essam El-Zahar Abdelhalim ebaid Department of Mathematics Faculty of ScienceUniversity of TabukTabuk71491Saudi Arabia Department of Mathematics College of Sciences and Humanities in Al-KharjPrince Sattam bin Abdulaziz UniversityAlkharj11942Saudi Arabia Department of Basic Engineering Science Faculty of EngineeringMenofia UniversityShebin El-Kom32511Egypt

In this paper,the mathematical model describing the third-grade non-Newtonian blood flow suspended with nanoparticles through porous arteries is exactly *** present physical model was solved in the research literature via the optimal homotopy analysis method and the collocation method,where the obtained solution was compared with the numerical fourth-order Runge-Kutta ***,the present paper only introduces a new approach to obtain the exact solution of the concerned system and implements such exact solution as a reference to validate the published approximate *** remarks on the previously published results are observed and discussed in detail through tables and *** view of the present calculations,the obtained results in the literature by Ghasemi et al.[Ghasemi,Hatami,Sarokolaie et al.(2015)]may need ***,it is found that the obtained approximate results in the relevant literature agree with the current exact ones up to only two or three decimal places,at ***,the present approach along with the obtained results reflexes the effectiveness and efficiency of our analysis when compared with the corresponding study in the ***,the present results can be directly invested for similar future problems of the same constructions.

关键词： Nanofluid blood flow porous artery nanoparticle exact solution

Hypergeometric Series Solution to a Class of Second-Order Boundary Value Problems via Laplace Transform with Applications to Nanofluids

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Communications in Theoretical Physics 2017年第3期67卷 231-234页

作者： Abdelhalim ebaid Abdul-Majid Wazwaz Elham Alali Basem S.Masaedeh Department of Mathematics Faculty of Science University of Tabuk P.O. Box 741 Tabuk 71491 Saudi Arabia Department of Mathematics and Computer Science Saint Xavier University Chicago IL 60655 USA

Very recently, it was observed that the temperature of nanofluids is finally governed by second-order ordinary differential equations with variable coefficients of exponential orders. Such coefficients were then transformed to polynomials type by using new independent variables. In this paper, a class of second-order ordinary differential equations with variable coefficients of polynomials type has been solved analytically. The analytical solution is expressed in terms of a hypergeometric function with generalized parameters. Moreover, applications of the present results have been applied on some selected nanofluids problems in the literature. The exact solutions in the literature were derived as special cases of our generalized analytical solution.

关键词： ordinary differential equation hypergeometric series boundary value problem exact solution Laplace transform nanofluid

Role of zinc as an antioxidant and anti-inflammatory to relieve cadmium oxidative stress induced testicular damage in rats

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Asian Pacific Journal of Tropical Biomedicine 2016年第12期6卷 1056-1064页

作者： Samir Abd El-Monem Bashandy Enayat Abdel Aziz Omara Hossam ebaid Mohamed Mahmoud Amin Mahmoud Sanad Soliman Department of Pharmacology Medical DivisionNational Research Centre Department of Pathology National Research Centre Department of Zoology College of ScienceKing Saud University Department of Zoology Faculty of ScienceEl-Minia University Department of Therapeutic Chemistry National Research Centre

Objective:To investigate the role of zinc in reducing the deleterious effects of cadmium on male ***:Rats were injected subcutaneously with CdCl_2 and ZnCl_2 at dose level of2.2 mg/kg(1/40 of LD50 of cadmium per day).Results:The rats treated with cadmium exhibited a significant increase in levels of testicular malondialdehyde,tumor necrosis factor-alpha,nitrogen oxide and inducible nitrogen oxide synthase immunostaining reaction,as well as an elevation of blood hydroperoxide and follicle stimulating *** addition,a significant decrease in testicular ascorbic acid,zinc,reduced glutathione,catalase,superoxide dismutase,sex organ weight,plasma testosterone and luteinizing hormone were observed in the cadmium *** motility and count were decreased with cadmium treatment,while sperm abnormalities elevated *** treatment was found to mitigate the toxic effects of cadmium on oxidative stress,spermatogenesis,sex hormones,and inflammatory *** injected with cadmium showed intense histopathological *** manifested protective role and markedly reduced tissues damage induced by ***:The protective effect of zinc can be attributed to its antioxidant and antiinflammatory properties.

关键词： Zinc Cadmium Oxidative stress Immunohistochemistry Sperms Inflammatory markers

Integrating Radar Altimeters and Optical Imagery Data for Estimating Water Volume Variations in Lakes and Reservoirs (Case Study: Lake Nasser)

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Journal of Geographic Information System 2017年第6期9卷 648-662页

作者： Hala M. ebaid Medhat Aziz Survey Research Institute National Water Research Center Giza Egypt Nile Research Institute National Water Research Center Cairo Egypt

Monitoring of variations in water for lakes and reservoirs is a requirement for meeting human needs and assessing ongoing climatic changes. However, regular gauging networks fail to provide the information needed for water volume data. The aim of this study is to evaluate an approach to estimate water volume variation for the southern part of Lake Nasser in Egypt without in-situ gauge measurements and bathymetry maps. Combination of both Hydroweb satellite altimetry and Landsat 8 satellite imagery data was used. As compared to in-situ water levels, satellite altimetry provided accurate water levels variations for Lake Nasser;the RMSE was 0.28 m, with excellent agreement (R2 is 0.98). The lowest water level of altimetry database i.e. 174.57 m was used as a reference level for estimating water volumes variations for the study duration 8/2014-6/2015. All water altimetry levels were converted to differences of recorded water level above the lowest altimetry Level (ΔWL). Series of Landsat 8 imagery data were selected to extract surface areas corresponding to radar altimetry water levels dates. Areas-ΔWL relationship model was established as a polynomial function: A = f(ΔWL), and therefore, the relationship of the water volume above the lowest water level for the study time (ΔV) and ΔWL was obtained through the analytical integration of (Area-ΔWL) model. Another approach (Heron method) was also applied for estimating water volume variations. Validation of these two approaches showed that estimated water volume variations above reference water level using both methods i.e. integration and Heron agreed well with in-situ measurements of volume variation deduced from recent bathymetry map and in-situ water levels (R2 for both methods = 0.98). The RMSE for integration method is 323.89 MCM and for Heron method was 318.09 MCM, being approximately 13.2% of the mean volume variations above the lowest reference water level for mean surface area ≈

关键词： Radar Altimetry Water Volume Change Landsat 8 Lake Nasser Egypt

New Analytic Solution for Ambartsumian Equation

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Journal of Mathematics and System Science 2018年第7期8卷 182-186页

作者： Fahad M.Alharbi Abdelhalim ebaid Department of Mathematics Faculty of ScienceUniversity of TabukP.O.Box 741Tabuk 71491Saudi Arabia

Analytical solution is obtained for Ambartsumian equation in this *** equation is of application in *** obtained solution has many advantages over the published one in the literature as shown by several comparisons.

关键词： Delay equation analytic solution

Solving a Delay Differential Equation by Two Direct Approaches

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Journal of Mathematics and System Science 2019年第2期9卷 54-56页

作者： N. O. Alatawi A. ebaid Department of Mathematics Faculty of ScienceUniversity of TabukP.O.Box 741Tabuk 71491Saudi Arabia

The Ambartsumian equation is an application of the theory of surface brightness in the milky way. It is a linear differential equation involving a proportional delay term. In this paper, two different approaches have been used to obtain the power series solution of Ambartsumian equation. The obtained series solution by the suggested approaches agrees with the published solution in the literature. However, the current approaches are not only very simple but also straightforward.

关键词： Ambartsumian equation milky way series solution

那不勒斯热袍菌纤维素酶的表达、酶学性质分析及应用

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那不勒斯热袍菌纤维素酶的表达、酶学性质分析及应用

作者： Reham Mohammed Mohammed ebaid 江苏大学

学位级别：硕士

在生物质的各种工业应用中,生物燃料的生产越来越受到重视。许多因素影响生物质能转化为生物燃料,如生物质成分、水分含量和最终所需的能源产品。在各种转化方法中,酶解法将生物质转化为可发酵糖具有高产、低能耗、高选择性和生态友好... 详细信息

在生物质的各种工业应用中,生物燃料的生产越来越受到重视。许多因素影响生物质能转化为生物燃料,如生物质成分、水分含量和最终所需的能源产品。在各种转化方法中,酶解法将生物质转化为可发酵糖具有高产、低能耗、高选择性和生态友好等优点。在这方面,超嗜热酶在极端温度下的稳定性使它们具有独特的生物质转化潜力。近年来,为了提高耐热酶的生物产量和稳定性,人们进行了大量的试验。除了优化生长条件和使用化学方法外,还开发了许多新的遗传表达系统。本研究利用pHsh-T载体,从那不勒斯热热袍菌中分离到嗜热纤维素酶(hyperthermophilic cellulase,HTC)基因并在大肠杆菌中表达。确定了该酶95℃为最佳温度。最佳pH值在6.0-6.5之间,在碱性环境中比在酸性环境中更稳定。此外,该酶在95℃孵育时表现出较高的热稳定性,孵育5小时后活性最高。HTC的这些优越性质有力地支持了酶在纤维素生物质水解中用于生物燃料生产或其他工业中的应用。木质纤维素生物质中木质素的存在以及纤维素和半纤维素的解聚限制了酶法转化生物质的效率。微藻和蓝藻由于其细胞壁缺乏木质素,因此被认为是生物燃料(第三代)的潜在原料。在不同种类的蓝藻中,螺旋藻(Spirulina platensis)被认为是最具应用潜力的原料,包括生物燃料的生产。因此,本论文研究了静态磁场(SMF)对螺旋藻生物量生产、碳水化合物积累的影响及其对镉离子(Cd)去除率的影响。此外,还研究了HTC对SMF和高浓度Cd条件下生长的螺旋藻水解的影响。施用6 h·天的SMF,螺旋藻生物量的生产强度最高为0.198 g·L·天。然而,Cd浓度为10 mg·L和15mg·L时,螺旋藻生物量分别比对照降低了8.8%和12.5%。与对照相比,SMF组合显著提高了30.1%的生物量。另一方面,初始Cd浓度的增加导致Cd去除率显著降低,分别为10 mg·L和15 mg·L时的79.7%和61.5%。有趣的是,在初始Cd浓度为10mg·L和15 mg·L的培养基中,使用SMF 6 h·天可以提高Cd的去除率,在20天后,这两种培养基的去除率分别提高了91.4%和82.3%,分别比未经SMF处理的培养基提高了6.3%和25.3%。此外,SMF的应用导致碳水化合物的积累,并同时促进生长,这导致碳水化合物的产量在未经处理的培养基上显著增加。纤维分析结果为7.3%的dw纤维素和13.2%的dw半纤维素,未检测出木质素。以螺旋藻为原料,采用酶法水解螺旋藻,并与传统的酸预处理方法进行了比较。在最高应用浓度(10%)的应用条件下,酸预处理显示,最大还原糖量为1.37μg·mL。然而,使用10μL HTC酶,孵化基质30分钟,应用结果显示达到它的最大还原糖量为1.39μg·mL。另外利用红外光谱来确定纤维水解的程度,分析了结构性变化。在生物质原料中,3422 cm的条带对应O-H拉伸,表明存在纤维素和/或酸。酸预处理使该峰增大是由于样品被酸饱和,而HTC处理使该峰显著降低,证实了纤维素结构在消化纤维中由于破坏了纤维素中的氢键而变得疏松。2945 cm处的吸收带与C-H拉伸有关,证实了纤维素的甲基和亚甲基基团在酸和酶预处理后均被部分除去。此外,酶处理样品在1654 cm(C=O拉伸)处峰值强度的降低可能是由于酶水解纤维素导致半纤维素的部分降解。在95℃培养12小时后,HTC在结晶纤维素上的相对活性最大。然而,当孵育时间增加到48小时后,相对活性变化不明显。因此,该酶与纤维素(12h)相比与纤维素(5h)相比,需要更长的时间才能达到其最大活性。综上所述,目前的结果证实了HTC对纤维素及其结晶形态的显著作用,在未来将有广泛的工业应用。

关键词：纤维素酶超耐热酶热稳定性那不勒斯热袍菌生物质螺旋藻