This paper investigates the effects of gypsum powder from the gypsum plant in Adigudem on chemical properties of soil as well as the yield of two major crops, wheat (Triticum aestivum) and barley (Hordeum vulgare). Three mixes of 10kg of soil with 0%, 10%, 30%, and 50% proportion of gypsum powder were used for pot experiments under glasshouse conditions at Mekelle University. One bulk soil sample was collected from a spot at 4 km from the eastern side of the plant. The chemical concentration of major elements Ca, K, Na, Mg, and Mn, and trace elements, Cd, Zn, Cu, Pb, Cr, and Fe in soil and plant parts were determined using an Atomic absorption spectrometer as well as NO3, PO4 and SO4 using UV-spectrometer. The results suggest that the gypsum powder enhances metals and anion content in soil and in crop parts compared to the control sample. The chemical constituents in soil and crop parts showed negligible variation with increasing proportions of gypsum powder. Gypsum loaded Ca, SO4, Mn, and Pb onto the soil, which exhibited higher Mg, Cu, Mo, Cd, NO3, and PO4 but the comparable concentrations of Fe, K, Zn, and Cr in decreasing order. However, a direct relationship was noted in chemical constituent loadings along the pathway: powder-soil-crop in a similar fashion in the three mixes. Factor analyses revealed that wheat parts have a higher accumulation of nutrients than the barley parts with higher content in its growth soil blends. As an extension of this research, the in-situ investigation is recommended to assess the direct impact of the gypsum powder emitted over the soil and crops.
{"title":"Investigating the Effect of Gypsum Powder on Chemical Constituents of Soil and Selected Crops, Adigudem, Tigray, Ethiopia","authors":"Berhe Hailu, S. Estifanos","doi":"10.4314/mejs.v13i1.9","DOIUrl":"https://doi.org/10.4314/mejs.v13i1.9","url":null,"abstract":"This paper investigates the effects of gypsum powder from the gypsum plant in Adigudem on chemical properties of soil as well as the yield of two major crops, wheat (Triticum aestivum) and barley (Hordeum vulgare). Three mixes of 10kg of soil with 0%, 10%, 30%, and 50% proportion of gypsum powder were used for pot experiments under glasshouse conditions at Mekelle University. One bulk soil sample was collected from a spot at 4 km from the eastern side of the plant. The chemical concentration of major elements Ca, K, Na, Mg, and Mn, and trace elements, Cd, Zn, Cu, Pb, Cr, and Fe in soil and plant parts were determined using an Atomic absorption spectrometer as well as NO3, PO4 and SO4 using UV-spectrometer. The results suggest that the gypsum powder enhances metals and anion content in soil and in crop parts compared to the control sample. The chemical constituents in soil and crop parts showed negligible variation with increasing proportions of gypsum powder. Gypsum loaded Ca, SO4, Mn, and Pb onto the soil, which exhibited higher Mg, Cu, Mo, Cd, NO3, and PO4 but the comparable concentrations of Fe, K, Zn, and Cr in decreasing order. However, a direct relationship was noted in chemical constituent loadings along the pathway: powder-soil-crop in a similar fashion in the three mixes. Factor analyses revealed that wheat parts have a higher accumulation of nutrients than the barley parts with higher content in its growth soil blends. As an extension of this research, the in-situ investigation is recommended to assess the direct impact of the gypsum powder emitted over the soil and crops.","PeriodicalId":18948,"journal":{"name":"Momona Ethiopian Journal of Science","volume":"1 1","pages":""},"PeriodicalIF":0.3,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70566911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Citrus fruit production is suffering from various yield-limiting factors particularly the sucking pests viz, citrus leafminer Phyllocnistis citrella , woolly whitefly, Aleurothrixus floccosus and scale insects especially armored scales Aonidiella auriantii . The present paper tries to identify the effective botanical insecticides against these insect pests on citrus orange. An experiment was conducted in the established citrus orange farm in Kolla Temben at two farmer’s fields, Adiha and Agibe during the off-season of 2018 under irrigation growing condition in a randomized complete block design with six treatments and replicated thrice. The findings in both experimental sites showed that the neem seed extract had a significantly (P=0.001) lower leafminer infestation levels compared to the untreated control which is on par to the insecticide treatment of dimethoate. On the other hand, in both areas, whitefly mortality of more than 81% on average was recorded from neem seed extract followed by Tree tobacco (70%) (P=0.001). For scale insects however, in both experimental sites, the highest mean percent mortality was recorded from the insecticide dimethoate 40% EC (86.9%, 87.2 & 86.0%on average) followed by neem seed and tree tobacco extracts,70.1 and 65.4% respectively. The botanicals particularly the neem seed extracts followed by tree tobacco are as effective as the chemical insecticide, dimethoate 40% EC, even superior in some cases, in controlling the target pests. Therefore, these botanicals could be used as an IPM component for against the target pests.
{"title":"Evaluation of Some Botanical Extracts Against Major Insect Pests (Leafminer, Armored scale and Woolly Whitefly) of Citrus Plants in Central Zone of Tigray, North Ethiopia","authors":"F. Ibrahim, Tsehaye Hadush, G. Abraha, A. Alemu","doi":"10.4314/mejs.v11i2.6","DOIUrl":"https://doi.org/10.4314/mejs.v11i2.6","url":null,"abstract":"Citrus fruit production is suffering from various yield-limiting factors particularly the sucking pests viz, citrus leafminer Phyllocnistis citrella , woolly whitefly, Aleurothrixus floccosus and scale insects especially armored scales Aonidiella auriantii . The present paper tries to identify the effective botanical insecticides against these insect pests on citrus orange. An experiment was conducted in the established citrus orange farm in Kolla Temben at two farmer’s fields, Adiha and Agibe during the off-season of 2018 under irrigation growing condition in a randomized complete block design with six treatments and replicated thrice. The findings in both experimental sites showed that the neem seed extract had a significantly (P=0.001) lower leafminer infestation levels compared to the untreated control which is on par to the insecticide treatment of dimethoate. On the other hand, in both areas, whitefly mortality of more than 81% on average was recorded from neem seed extract followed by Tree tobacco (70%) (P=0.001). For scale insects however, in both experimental sites, the highest mean percent mortality was recorded from the insecticide dimethoate 40% EC (86.9%, 87.2 & 86.0%on average) followed by neem seed and tree tobacco extracts,70.1 and 65.4% respectively. The botanicals particularly the neem seed extracts followed by tree tobacco are as effective as the chemical insecticide, dimethoate 40% EC, even superior in some cases, in controlling the target pests. Therefore, these botanicals could be used as an IPM component for against the target pests.","PeriodicalId":18948,"journal":{"name":"Momona Ethiopian Journal of Science","volume":"11 1","pages":"258-275"},"PeriodicalIF":0.3,"publicationDate":"2020-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4314/mejs.v11i2.6","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70566434","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper, a second degree generalized successive over relaxation iterative method for solving system of linear equations based on the decomposition A= Dm+Lm+Um is presented and the convergence properties of the proposed method are discussed. Two numerical examples are considered to show the efficiency of the proposed method. The results presented in tables show that the Second Degree Generalized Successive Over Relaxation Iterative method is more efficient than the other methods considered based on number of iterations, computational running time and accuracy. Keywords: Second Degree, Generalized Gauss Seidel, Successive over relaxation, Convergence.
{"title":"Second Degree Generalized Successive Over Relaxation Method for Solving System of Linear Equations","authors":"Firew Hailu, G. Gonfa, Hailu Muleta Chemeda","doi":"10.4314/MEJS.V12I1.4","DOIUrl":"https://doi.org/10.4314/MEJS.V12I1.4","url":null,"abstract":"In this paper, a second degree generalized successive over relaxation iterative method for solving system of linear equations based on the decomposition \u0000A= Dm+Lm+Um is presented and the convergence properties of the proposed method are discussed. Two numerical examples are considered to show the efficiency of the proposed method. The results presented in tables show that the Second Degree Generalized Successive Over Relaxation Iterative method is more efficient than the other methods considered based on number of iterations, computational running time and accuracy. Keywords: Second Degree, Generalized Gauss Seidel, Successive over relaxation, Convergence.","PeriodicalId":18948,"journal":{"name":"Momona Ethiopian Journal of Science","volume":"12 1","pages":"60-71"},"PeriodicalIF":0.3,"publicationDate":"2020-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49481251","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Micro and Small Enterprises (MSE) have become the focus of attention for the economic development, economic growth and job creations in the world. Majority of the firms worldwide are dominated by businesses of micro and small enterprises. In developing countries, the informal sector that mainly establishes MSE remains the major source of employment and income for the urban population. A study was conducted to examine the performance of MSE in three zones of Tigray State, namely, Southern zone, Mekelle zone and Eastern zone. The data was collected using structured questionnaire on 246 MSE business owners. The data are analyzed using multiple linear regressions (dummy), Cross tabulations and chi-square test for test of independence. The result revealed that Gender, initial capital, enterprise and job type are found to be important factors of performance of MSE. There is a gender difference on sector type, education level and work sheds of micro and small enterprises business owner. The result also showed that initial capital has positively affected the performance of business owners and men headed business owners have better performance than female headed business owners. Keywords: Micro- and Small Enterprises, Performance, Gender, Tigray, Ethiopia.
{"title":"Performance of Micro and Small Enterprisers in Tigray, Northern Ethiopia","authors":"Gebretsadik Gebru Wubet, G. Mmopelwa","doi":"10.4314/mejs.v12i1.7","DOIUrl":"https://doi.org/10.4314/mejs.v12i1.7","url":null,"abstract":"Micro and Small Enterprises (MSE) have become the focus of attention for the economic development, economic growth and job creations in the world. Majority of the firms worldwide are dominated by businesses of micro and small enterprises. In developing countries, the informal sector that mainly establishes MSE remains the major source of employment and income for the urban population. A study was conducted to examine the performance of MSE in three zones of Tigray State, namely, Southern zone, Mekelle zone and Eastern zone. The data was collected using structured questionnaire on 246 MSE business owners. The data are analyzed using multiple linear regressions (dummy), Cross tabulations and chi-square test for test of independence. The result revealed that Gender, initial capital, enterprise and job type are found to be important factors of performance of MSE. There is a gender difference on sector type, education level and work sheds of micro and small enterprises business owner. The result also showed that initial capital has positively affected the performance of business owners and men headed business owners have better performance than female headed business owners. \u0000Keywords: Micro- and Small Enterprises, Performance, Gender, Tigray, Ethiopia.","PeriodicalId":18948,"journal":{"name":"Momona Ethiopian Journal of Science","volume":"12 1","pages":"103-122"},"PeriodicalIF":0.3,"publicationDate":"2020-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43237542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper, a seven-step block method for the solution of first order initial value problem in ordinary differential equations based on collocation of the differential equation and interpolation of the approximate solution using power series have been formed. The method is found to be consistent and zero-stable which guarantees convergence. Finally, numerical examples are presented to illustrate the accuracy and effectiveness of the method. Keywords: Power series, Collocation, Interpolation, Block method, Stiff.
{"title":"A Seven-Step Block Multistep Method for the Solution of First Order Stiff Differential Equations","authors":"S. Gebregiorgis, H. Muleta","doi":"10.4314/mejs.v12i1.5","DOIUrl":"https://doi.org/10.4314/mejs.v12i1.5","url":null,"abstract":"In this paper, a seven-step block method for the solution of first order initial value problem in ordinary differential equations based on collocation of the differential equation and interpolation of the approximate solution using power series have been formed. The method is found to be consistent and zero-stable which guarantees convergence. Finally, numerical examples are presented to illustrate the accuracy and effectiveness of the method. \u0000 Keywords: Power series, Collocation, Interpolation, Block method, Stiff.","PeriodicalId":18948,"journal":{"name":"Momona Ethiopian Journal of Science","volume":"12 1","pages":"72-82"},"PeriodicalIF":0.3,"publicationDate":"2020-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44796309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Equines are providing traction power and transport services, like pulling cart, packing and riding, at low cost in both rural and urban areas of Ethiopia. A cross-sectional study was conducted in Gondar city from November 2014 to April 2015 to assess major health problems and to investigate the economic contribution of cart horses to livelihood of the community. Cart horses were randomly selected from the study area. Observational study was also conducted and semi-structured questionnaire survey was administered to all cart horse owners. The study revealed that behavioral responses, skin coat and dental conditions were significantly associated with body condition and age of cart horses (p<0.05). Wound and musculoskeletal problem had no significant association with body condition and age of working horses. Young horses with good body conditions were more prone to wounds (75%) than the older horses with poor body conditions. The majority of the carthorse owners used their horses for transportation for long hours (> 8 hours) per a day, 5-6 days per week and loaded them 500-700 kg. The income in cash for the cart horse owners was recorded as 80-100 ETB per day. The current study indicated that the cart horse contribution to livelihood of communities is considerable. The working animals deserve better husbandry and veterinary care to sustain their contribution. We suggest a more detailed and systematic study be conducted in the study area to influence policy makers towards better regulation in animal welfare. Keywords: Cart horses, Economic contribution, Gondar, Ethiopia.
{"title":"Economic Contribution of Cart Horses to the Livelihoods of Families in Gondar Town Ethiopia","authors":"Hamelmal Asfaw, Gebrehiwot Tadesse","doi":"10.4314/mejs.v12i1.9","DOIUrl":"https://doi.org/10.4314/mejs.v12i1.9","url":null,"abstract":"Equines are providing traction power and transport services, like pulling cart, packing and riding, at low cost in both rural and urban areas of Ethiopia. A cross-sectional study was conducted in Gondar city from November 2014 to April 2015 to assess major health problems and to investigate the economic contribution of cart horses to livelihood of the community. Cart horses were randomly selected from the study area. Observational study was also conducted and semi-structured questionnaire survey was administered to all cart horse owners. The study revealed that behavioral responses, skin coat and dental conditions were significantly associated with body condition and age of cart horses (p<0.05). Wound and musculoskeletal problem had no significant association with body condition and age of working horses. Young horses with good body conditions were more prone to wounds (75%) than the older horses with poor body conditions. The majority of the carthorse owners used their horses for transportation for long hours (> 8 hours) per a day, 5-6 days per week and loaded them 500-700 kg. The income in cash for the cart horse owners was recorded as 80-100 ETB per day. The current study indicated that the cart horse contribution to livelihood of communities is considerable. The working animals deserve better husbandry and veterinary care to sustain their contribution. We suggest a more detailed and systematic study be conducted in the study area to influence policy makers towards better regulation in animal welfare. \u0000Keywords: Cart horses, Economic contribution, Gondar, Ethiopia.","PeriodicalId":18948,"journal":{"name":"Momona Ethiopian Journal of Science","volume":"1 1","pages":""},"PeriodicalIF":0.3,"publicationDate":"2020-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45654988","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"CORRECTION to \"Study on gross pulmonary lesions in lungs of slaughtered animals and their economics importance in Tigray, Ethiopia” MEJS, 2015, 7(1): 46-54.","authors":"Mejs","doi":"10.4314/MEJS.V12I1","DOIUrl":"https://doi.org/10.4314/MEJS.V12I1","url":null,"abstract":"","PeriodicalId":18948,"journal":{"name":"Momona Ethiopian Journal of Science","volume":"12 1","pages":"148-148"},"PeriodicalIF":0.3,"publicationDate":"2020-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42056526","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Yohannes, Leul Kidane, B. Abraha, Tadesse Beyene
Camelina sativa is a promising low-input, high yielding biodiesel crop that can be suitable to grow on marginal lands and is a good source of omega-3 fatty acids. But, saltiness is an overall issue of agriculture that constrains the germination, development and productivity of plant because of osmotic and ionic poisonous quality impacts. The aim of this study was to assess the effect of salinity (NaCl and KCl) on germination and early seedling growth of Camelina sativa. Camelina sativa seeds were obtained from agricultural research sector of Wachemo University. In the laboratory, six salinity levels of NaCl and KCl (0, 1, 2, 3, 4 and 5 g/L) were prepared and arranged in completely randomized design with four replications. The result of the study revealed that C. sativa seedlings were differ significantly (p<0.05) on speed of germination, germination percentage, germination index, shoot length, root length, vigor index, root shoot ratio and seedling fresh weight, relative injury rates of NaCl and KCl, shoot height reduction and root height reduction. However, there is no significant effect between salt type versus salinity level and salt type in all parameters tested except shoot length and shoot height reduction at 5% significant level. The increase in both salts (NaCl and KCl) concentration in culture medium causes a significant decreases in speed of germination, germination percentage, germination index, shoot length, root length, vigor index, root shoot ratio and seedling fresh weight of the salt treated C. sativa seeds as compared with the control (C. sativa seeds watered with distilled water). Similarly, relative injury rates NaCl and KCl shoot height reduction, root height reduction were highly increased as salinity level increases. Generally, as the concentration of NaCl and KCl was increased the overall germination and early seedling performance of C. sativa decreased. The effect of salinity on physiology, molecular and biochemical of properties of C. sativa should be studied. Keywords: Camelina sativa, Salinity effect, NaCl, KCl, Seed germination, Seedling growth.
{"title":"Effect of Salt Stresses on Seed Germination and Early Seedling Growth of Camelina sativa L.","authors":"G. Yohannes, Leul Kidane, B. Abraha, Tadesse Beyene","doi":"10.4314/MEJS.V12I1.1","DOIUrl":"https://doi.org/10.4314/MEJS.V12I1.1","url":null,"abstract":"Camelina sativa is a promising low-input, high yielding biodiesel crop that can be suitable to grow on marginal lands and is a good source of omega-3 fatty acids. But, saltiness is an overall issue of agriculture that constrains the germination, development and productivity of plant because of osmotic and ionic poisonous quality impacts. The aim of this study was to assess the effect of salinity (NaCl and KCl) on germination and early seedling growth of Camelina sativa. Camelina sativa seeds were obtained from agricultural research sector of Wachemo University. In the laboratory, six salinity levels of NaCl and KCl (0, 1, 2, 3, 4 and 5 g/L) were prepared and arranged in completely randomized design with four replications. The result of the study revealed that C. sativa seedlings were differ significantly (p<0.05) on speed of germination, germination percentage, germination index, shoot length, root length, vigor index, root shoot ratio and seedling fresh weight, relative injury rates of NaCl and KCl, shoot height reduction and root height reduction. However, there is no significant effect between salt type versus salinity level and salt type in all parameters tested except shoot length and shoot height reduction at 5% significant level. The increase in both salts (NaCl and KCl) concentration in culture medium causes a significant decreases in speed of germination, germination percentage, germination index, shoot length, root length, vigor index, root shoot ratio and seedling fresh weight of the salt treated C. sativa seeds as compared with the control (C. sativa seeds watered with distilled water). Similarly, relative injury rates NaCl and KCl shoot height reduction, root height reduction were highly increased as salinity level increases. Generally, as the concentration of NaCl and KCl was increased the overall germination and early seedling performance of C. sativa decreased. The effect of salinity on physiology, molecular and biochemical of properties of C. sativa should be studied. \u0000Keywords: Camelina sativa, Salinity effect, NaCl, KCl, Seed germination, Seedling growth.","PeriodicalId":18948,"journal":{"name":"Momona Ethiopian Journal of Science","volume":" ","pages":""},"PeriodicalIF":0.3,"publicationDate":"2020-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4314/MEJS.V12I1.1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49109022","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper investigates the boundary layer analysis for magnetohydrodynamic partial slip flow and heat transfer of nanofluids through porous media over a stretching sheet with convective boundary condition. Four types of nanoparticles, namely copper, alumina, copper oxide and titanium oxide in the ethylene glycol (50%, i.e., Pr = 29.86) and water (i.e., Pr = 6.58) based fluids are studied. The governing highly nonlinear and coupled partial differential equations are solved numerically using fourth order Runge-Kutta method with shooting techniques. The velocity and temperature profiles are obtained and utilized to compute the skin friction coefficient and local Nusselt number for different values of the governing parameters viz. nanoparticle volume fraction parameter, magnetic field parameter, porosity parameter, velocity slip parameter and convective parameter. It is found that the velocity distribution of the nanofluids is a decreasing function of the magnetic parameter, porosity parameter, and velocity slip parameter. However, temperature of the nanofluids is an increasing function of magnetic field parameter, nanoparticle volume fraction parameter, porosity parameter, velocity slip parameter and convective parameter. The flow and heat transfer characteristics of the four nanofluids are compared. Moreover, comparison of the numerical results is made with previously published works for special cases and an excellent agreement is found. Keywords: Magnetohydrodynamics, Partial Slip, Porous medium, Convective boundary, Nanofluid.
{"title":"MHD Partial Slip Flow and Heat Transfer of Nanofluids through a Porous Medium Over a Stretching Sheet with Convective Boundary Condition","authors":"Y. Yirga","doi":"10.4314/mejs.v12i1.3","DOIUrl":"https://doi.org/10.4314/mejs.v12i1.3","url":null,"abstract":"This paper investigates the boundary layer analysis for magnetohydrodynamic partial slip flow and heat transfer of nanofluids through porous media over a stretching sheet with convective boundary condition. Four types of nanoparticles, namely copper, alumina, copper oxide and titanium oxide in the ethylene glycol (50%, i.e., Pr = 29.86) and water (i.e., Pr = 6.58) based fluids are studied. The governing highly nonlinear and coupled partial differential equations are solved numerically using fourth order Runge-Kutta method with shooting techniques. The velocity and temperature profiles are obtained and utilized to compute the skin friction coefficient and local Nusselt number for different values of the governing parameters viz. nanoparticle volume fraction parameter, magnetic field parameter, porosity parameter, velocity slip parameter and convective parameter. It is found that the velocity distribution of the nanofluids is a decreasing function of the magnetic parameter, porosity parameter, and velocity slip parameter. However, temperature of the nanofluids is an increasing function of magnetic field parameter, nanoparticle volume fraction parameter, porosity parameter, velocity slip parameter and convective parameter. The flow and heat transfer characteristics of the four nanofluids are compared. Moreover, comparison of the numerical results is made with previously published works for special cases and an excellent agreement is found. \u0000 Keywords: Magnetohydrodynamics, Partial Slip, Porous medium, Convective boundary, Nanofluid.","PeriodicalId":18948,"journal":{"name":"Momona Ethiopian Journal of Science","volume":"12 1","pages":"39-59"},"PeriodicalIF":0.3,"publicationDate":"2020-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47128598","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The lack of standard water analysis equipment as well as inadequate trained personnel especially in the developing countries has discouraged many researchers in such countries to execute water quality researches. Hence, this paper presents developed mathematical relationship among some physicochemical parameters in order to aid the determination of the concentrations of certain parameters with the use of minimal equipment. This was achieved by weekly analyzing 7 physicochemical parameters of two sources of potable water (tap water and borehole water) stored in different containers for a period of 6 weeks using standard methods. The storage containers used were black plastic tank, blue plastic tank, green plastic tank, coated steel metal tank, uncoated steel metal tank and clay pot. The parameters examined were turbidity, electrical conductivity (EC), pH, alkalinity, chloride ion (Cl-), dissolved oxygen (DO) and total hardness. Results showed that the relationship between electrical conductivity (EC), alkalinity (Alk), total hardness (TH) and chloride ion (Cl-) is given as; EC = -224.8066493 + 6.244028022(Alk) + 0.28204735(TH) + 0.000518108(Cl-). A programing language was written on the models using Visual Basic.Net (VB.Net) version 2018. Keywords: Water, Physicochemical, Parameters, Function, Equation.
{"title":"Multiple Linear Regression (MLR) Model: A Tool for Water Quality Interpretation","authors":"Ogbozige F. J, Toko M. A, Arawo C.C","doi":"10.4314/MEJS.V12I1.8","DOIUrl":"https://doi.org/10.4314/MEJS.V12I1.8","url":null,"abstract":"The lack of standard water analysis equipment as well as inadequate trained personnel especially in the developing countries has discouraged many researchers in such countries to execute water quality researches. Hence, this paper presents developed mathematical relationship among some physicochemical parameters in order to aid the determination of the concentrations of certain parameters with the use of minimal equipment. This was achieved by weekly analyzing 7 physicochemical parameters of two sources of potable water (tap water and borehole water) stored in different containers for a period of 6 weeks using standard methods. The storage containers used were black plastic tank, blue plastic tank, green plastic tank, coated steel metal tank, uncoated steel metal tank and clay pot. The parameters examined were turbidity, electrical conductivity (EC), pH, alkalinity, chloride ion (Cl-), dissolved oxygen (DO) and total hardness. Results showed that the relationship between electrical conductivity (EC), alkalinity (Alk), total hardness (TH) and chloride ion (Cl-) is given as; EC = -224.8066493 + 6.244028022(Alk) + 0.28204735(TH) + 0.000518108(Cl-). A programing language was written on the models using Visual Basic.Net (VB.Net) version 2018. Keywords: Water, Physicochemical, Parameters, Function, Equation.","PeriodicalId":18948,"journal":{"name":"Momona Ethiopian Journal of Science","volume":"12 1","pages":"123-134"},"PeriodicalIF":0.3,"publicationDate":"2020-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47375379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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