The Experts below are selected from a list of 6948 Experts worldwide ranked by ideXlab platform
David K. Murage - One of the best experts on this subject based on the ideXlab platform.
-
Statistical Analysis of AC Breakdown Voltages in Persea Americana Oil,Mineral Insulation oil and their Mixtures
2020Co-Authors: Benard M. Makaa, George K. Irungu, David K. MurageAbstract:This paper reports on a comparative study of statistical Breakdown Voltage (BDV) in Persea Americana oil (PAO) and mineral insulation oil (MIO) and their respective mixtures. Two types of PAO are tested, that is extra virgin Persea Americana oil (EVPAO) and refined Persea Americana oil (RPAO). PAO and MIO and the oil mixtures (namely 50%RPAO+50%MIO and 50%EVPAO+50%MIO) are subjected to AC voltages. At least ten tests were carried out for each as per IEEE guide for the statistical analysis of electrical insulation breakdown data (IEEE 930 or IEC 62539). It is shown that the average AC breakdown voltage of RPAO is higher than that of MIO. It also observed that AC mean breakdown voltage of RPAO is higher than that of oils mixture (50%RPAO+50%MIO) and MIO. (50%RPAO+50%MIO) BDV is higher than that of MIO. AC mean breakdown voltage of EVPAO and MIO mixture is the lowest one. Thus PAO constitutes a potential liquid for replacing mineral oil in high voltage equipment.
-
Electrical and Physicochemical Properties of Persea Americana Oil as an Alternative Transformer Insulation Oil
2019 Southern African Universities Power Engineering Conference Robotics and Mechatronics Pattern Recognition Association of South Africa (SAUPEC RobM, 2019Co-Authors: Benard M. Makaa, George K. Irungu, David K. MurageAbstract:This paper reports the investigation of Persea Americana oil (PAO) as an alternative replacement of mineral insulating oil (MIO) in electrical insulation and especially in high voltage power transformers. Persea Americana oil has several advantages that recommend both its production and usage over that of MIO. It has high biodegradability, higher fire safety guarantee, non-toxicity and is renewable. Experiments to investigate the key physicochemical (i.e water content, viscosity, acidity, pour point, oxidation stability flash point...) and electrical (dielectric strength, dissipation factor) properties of PAO were conducted. The Ageing characteristics (dissipation factor, resistivity, total acidity) were also explored after accelerated ageing using open beaker method. Food grade extra virgin and refined Persea Americana oil was used for this investigation. For comparison, the corresponding properties of mineral insulation oil (MIO) in the same experimental conditions were also measured. The obtained results show that the average electrical and physicochemical properties of PAO meet the IEC and IEEE specifications for new natural liquid insulation oils. The obtained results show that the average AC breakdown voltage of PAO is 74kV and that of MIO is 65kV. This may suggest that Persea Americana oil can be used as an alternative transformer liquid insulation.
-
Investigation of Persea Americana Oil as an Alternative Transformer Insulation Oil
2019 IEEE Electrical Insulation Conference (EIC), 2019Co-Authors: Benard M. Makaa, George K. Irungu, David K. MurageAbstract:Mineral insulating fluids have conventionally been used as insulating liquids in electrical equipment for over a century. These fluids serve as dielectrics and coolants. They are however known to be environmentally toxic and are highly flammable. Hence, they require costly fire protection schemes and deluge systems. Increasing awareness of environmental protection and fire safety is leading to accelerating trend of looking for plant based oil alternatives that are environmentally friendly. Increase in power rating of electrical equipment also calls for high temperature performance insulating oils. Plant based dielectric fluids have been found to defeat mineral oils in many of these aspects. They are nontoxic, possess better thermal properties and have excellent biodegradability. In order to reduce the adverse environmental impact and to improve the fire safety of transformers, there is an increasing demand for plant based insulating liquids as transformer insulating oils. This paper presents results of series of experiments that were performed to investigate the electrical, chemical, physical and thermal properties of food grade Persea Americana ester (PAE) for possible use as insulation oil. For comparison, the corresponding properties of mineral insulation oil (MIO) in the same experimental conditions were also measured and compared with those of PAE. In this investigation, two different types of Persea Americana oil samples consisting of extra virgin and refined PAE were tested. The obtained results show that the average electrical, chemical, physical and thermal properties of PAE meet the IEC and IEEE specifications for new natural liquid insulation oils. This may suggest that Persea Americana oil can be tried as an alternative transformer liquid insulation.
Almir Goncalves Wanderley - One of the best experts on this subject based on the ideXlab platform.
-
anti diabetic activity of extract from Persea Americana mill leaf via the activation of protein kinase b pkb akt in streptozotocin induced diabetic rats
Journal of Ethnopharmacology, 2012Co-Authors: C R Lima, Carlos F B Vasconcelos, Joao Henrique Costasilva, C A Maranhao, Jorge Adelino Costa, Thiago M Batista, Everardo M Carneiro, Luiz Alberto Lira Soares, Fabiano Ferreira, Almir Goncalves WanderleyAbstract:Abstract Ethnopharmacological relevance The leaves of Persea Americana Mill. (Lauraceae) have been popularly used in the treatment of diabetes in countries in Latin America and Africa. Aim of the study To investigate the hypoglycaemic properties and to determine the molecular mechanism by which the hydroalcoholic extract of the leaves of Persea Americana reduce blood glucose levels in streptozotocin (STZ)-induced diabetes in rats via the enzymatic pathway of protein kinase B (PKB/Akt). Methods The hydroalcoholic extract of the leaves of Persea Americana (0.15 and 0.3 g/kg/day), vehicle and metformin (0.5 g/kg/day) were administered orally to STZ-diabetic rats (n = 7/group) for 4 weeks. Changes in body weight, food and water intake, fasting glucose levels and oral glucose tolerance were evaluated. Phosphorylation and the expression of PKB in the liver and soleus muscle were determined by Western blot. Results The hydroalcoholic extract of the leaves of Persea Americana reduced blood glucose levels and improved the metabolic state of the animals. Additionally, PKB activation was observed in the liver and skeletal muscle of treated rats when compared with untreated rats. Conclusion The results indicate that the hydroalcoholic extract of the leaves of Persea Americana has anti-diabetic properties and possibly acts to regulate glucose uptake in liver and muscles by way of PKB/Akt activation, restoring the intracellular energy balance.
-
Anti-diabetic activity of extract from Persea Americana Mill. leaf via the activation of protein kinase B (PKB/Akt) in streptozotocin-induced diabetic rats.
Journal of ethnopharmacology, 2012Co-Authors: C R Lima, Carlos F B Vasconcelos, C A Maranhao, Jorge Adelino Costa, Thiago M Batista, Everardo M Carneiro, Luiz Alberto Lira Soares, Fabiano Ferreira, João Henrique Costa-silva, Almir Goncalves WanderleyAbstract:Abstract Ethnopharmacological relevance The leaves of Persea Americana Mill. (Lauraceae) have been popularly used in the treatment of diabetes in countries in Latin America and Africa. Aim of the study To investigate the hypoglycaemic properties and to determine the molecular mechanism by which the hydroalcoholic extract of the leaves of Persea Americana reduce blood glucose levels in streptozotocin (STZ)-induced diabetes in rats via the enzymatic pathway of protein kinase B (PKB/Akt). Methods The hydroalcoholic extract of the leaves of Persea Americana (0.15 and 0.3 g/kg/day), vehicle and metformin (0.5 g/kg/day) were administered orally to STZ-diabetic rats (n = 7/group) for 4 weeks. Changes in body weight, food and water intake, fasting glucose levels and oral glucose tolerance were evaluated. Phosphorylation and the expression of PKB in the liver and soleus muscle were determined by Western blot. Results The hydroalcoholic extract of the leaves of Persea Americana reduced blood glucose levels and improved the metabolic state of the animals. Additionally, PKB activation was observed in the liver and skeletal muscle of treated rats when compared with untreated rats. Conclusion The results indicate that the hydroalcoholic extract of the leaves of Persea Americana has anti-diabetic properties and possibly acts to regulate glucose uptake in liver and muscles by way of PKB/Akt activation, restoring the intracellular energy balance.
Benard M. Makaa - One of the best experts on this subject based on the ideXlab platform.
-
Statistical Analysis of AC Breakdown Voltages in Persea Americana Oil,Mineral Insulation oil and their Mixtures
2020Co-Authors: Benard M. Makaa, George K. Irungu, David K. MurageAbstract:This paper reports on a comparative study of statistical Breakdown Voltage (BDV) in Persea Americana oil (PAO) and mineral insulation oil (MIO) and their respective mixtures. Two types of PAO are tested, that is extra virgin Persea Americana oil (EVPAO) and refined Persea Americana oil (RPAO). PAO and MIO and the oil mixtures (namely 50%RPAO+50%MIO and 50%EVPAO+50%MIO) are subjected to AC voltages. At least ten tests were carried out for each as per IEEE guide for the statistical analysis of electrical insulation breakdown data (IEEE 930 or IEC 62539). It is shown that the average AC breakdown voltage of RPAO is higher than that of MIO. It also observed that AC mean breakdown voltage of RPAO is higher than that of oils mixture (50%RPAO+50%MIO) and MIO. (50%RPAO+50%MIO) BDV is higher than that of MIO. AC mean breakdown voltage of EVPAO and MIO mixture is the lowest one. Thus PAO constitutes a potential liquid for replacing mineral oil in high voltage equipment.
-
Electrical and Physicochemical Properties of Persea Americana Oil as an Alternative Transformer Insulation Oil
2019 Southern African Universities Power Engineering Conference Robotics and Mechatronics Pattern Recognition Association of South Africa (SAUPEC RobM, 2019Co-Authors: Benard M. Makaa, George K. Irungu, David K. MurageAbstract:This paper reports the investigation of Persea Americana oil (PAO) as an alternative replacement of mineral insulating oil (MIO) in electrical insulation and especially in high voltage power transformers. Persea Americana oil has several advantages that recommend both its production and usage over that of MIO. It has high biodegradability, higher fire safety guarantee, non-toxicity and is renewable. Experiments to investigate the key physicochemical (i.e water content, viscosity, acidity, pour point, oxidation stability flash point...) and electrical (dielectric strength, dissipation factor) properties of PAO were conducted. The Ageing characteristics (dissipation factor, resistivity, total acidity) were also explored after accelerated ageing using open beaker method. Food grade extra virgin and refined Persea Americana oil was used for this investigation. For comparison, the corresponding properties of mineral insulation oil (MIO) in the same experimental conditions were also measured. The obtained results show that the average electrical and physicochemical properties of PAO meet the IEC and IEEE specifications for new natural liquid insulation oils. The obtained results show that the average AC breakdown voltage of PAO is 74kV and that of MIO is 65kV. This may suggest that Persea Americana oil can be used as an alternative transformer liquid insulation.
-
Investigation of Persea Americana Oil as an Alternative Transformer Insulation Oil
2019 IEEE Electrical Insulation Conference (EIC), 2019Co-Authors: Benard M. Makaa, George K. Irungu, David K. MurageAbstract:Mineral insulating fluids have conventionally been used as insulating liquids in electrical equipment for over a century. These fluids serve as dielectrics and coolants. They are however known to be environmentally toxic and are highly flammable. Hence, they require costly fire protection schemes and deluge systems. Increasing awareness of environmental protection and fire safety is leading to accelerating trend of looking for plant based oil alternatives that are environmentally friendly. Increase in power rating of electrical equipment also calls for high temperature performance insulating oils. Plant based dielectric fluids have been found to defeat mineral oils in many of these aspects. They are nontoxic, possess better thermal properties and have excellent biodegradability. In order to reduce the adverse environmental impact and to improve the fire safety of transformers, there is an increasing demand for plant based insulating liquids as transformer insulating oils. This paper presents results of series of experiments that were performed to investigate the electrical, chemical, physical and thermal properties of food grade Persea Americana ester (PAE) for possible use as insulation oil. For comparison, the corresponding properties of mineral insulation oil (MIO) in the same experimental conditions were also measured and compared with those of PAE. In this investigation, two different types of Persea Americana oil samples consisting of extra virgin and refined PAE were tested. The obtained results show that the average electrical, chemical, physical and thermal properties of PAE meet the IEC and IEEE specifications for new natural liquid insulation oils. This may suggest that Persea Americana oil can be tried as an alternative transformer liquid insulation.
George Awuku Asare - One of the best experts on this subject based on the ideXlab platform.
-
Evaluation of possible effects of Persea Americana seeds on female reproductive hormonal and toxicity profile.
Journal of ethnopharmacology, 2021Co-Authors: Ifeoma C. Orabueze, Rahmotallah Babalola, Obioma Azuonwu, Ini-ibehe Essien Okoko, George Awuku AsareAbstract:Abstract Ethnopharmacological relevance The seed of Avocado (Persea Americana, Lauraceae), non-edible part of the fruit is used as health product. It has been reported as traditional female contraceptive and sterilizer in Peru and some Asian countries and in Nigeria as cardio-protective agent. The present study focused on the effect of hydro-methanolic seed extract of Persea Americana on female hormones and toxicity profile using animal models. Materials and methods The serum follicle stimulating hormone (FSH) and progesterone (PROG) concentrations in mature non-pregnant female rats were assayed using hormonal kits. The toxicity profile was assessed using Lorke’s acute toxicity model, haemato-biochemical evaluation and histopathological studies of reproductive related organs. Parameters were measured on day-30, 60 and 90. Presence of biomarker flavonoid compounds were confirmed using High Performance Liquid Chromatography. Results The extract at 20, 100 and 500 mg kg -1 altered FSH and PROG hormone profile of the treated groups. The extract initially, dose-dependently decreased FSH level in day-30 (6.95, 3.97, 2.08 IU/L respectively) compared to untreated group before a significant increase was observed for day 60 and 90. Progesterone increased dose-dependently in the treated groups throughout the 90-day treatment duration. This may be Indicating cumulative effect on the hormone. No deleterious or toxicity effect was noticed. Conclusions The extract of Persea Americana seed affects female hormone activity. This may find application in various hormonal management procedures, maternal and reproductive health and fertility control/help health facilities. However, it should be used with caution in women intending to conceive.
C R Lima - One of the best experts on this subject based on the ideXlab platform.
-
anti diabetic activity of extract from Persea Americana mill leaf via the activation of protein kinase b pkb akt in streptozotocin induced diabetic rats
Journal of Ethnopharmacology, 2012Co-Authors: C R Lima, Carlos F B Vasconcelos, Joao Henrique Costasilva, C A Maranhao, Jorge Adelino Costa, Thiago M Batista, Everardo M Carneiro, Luiz Alberto Lira Soares, Fabiano Ferreira, Almir Goncalves WanderleyAbstract:Abstract Ethnopharmacological relevance The leaves of Persea Americana Mill. (Lauraceae) have been popularly used in the treatment of diabetes in countries in Latin America and Africa. Aim of the study To investigate the hypoglycaemic properties and to determine the molecular mechanism by which the hydroalcoholic extract of the leaves of Persea Americana reduce blood glucose levels in streptozotocin (STZ)-induced diabetes in rats via the enzymatic pathway of protein kinase B (PKB/Akt). Methods The hydroalcoholic extract of the leaves of Persea Americana (0.15 and 0.3 g/kg/day), vehicle and metformin (0.5 g/kg/day) were administered orally to STZ-diabetic rats (n = 7/group) for 4 weeks. Changes in body weight, food and water intake, fasting glucose levels and oral glucose tolerance were evaluated. Phosphorylation and the expression of PKB in the liver and soleus muscle were determined by Western blot. Results The hydroalcoholic extract of the leaves of Persea Americana reduced blood glucose levels and improved the metabolic state of the animals. Additionally, PKB activation was observed in the liver and skeletal muscle of treated rats when compared with untreated rats. Conclusion The results indicate that the hydroalcoholic extract of the leaves of Persea Americana has anti-diabetic properties and possibly acts to regulate glucose uptake in liver and muscles by way of PKB/Akt activation, restoring the intracellular energy balance.
-
Anti-diabetic activity of extract from Persea Americana Mill. leaf via the activation of protein kinase B (PKB/Akt) in streptozotocin-induced diabetic rats.
Journal of ethnopharmacology, 2012Co-Authors: C R Lima, Carlos F B Vasconcelos, C A Maranhao, Jorge Adelino Costa, Thiago M Batista, Everardo M Carneiro, Luiz Alberto Lira Soares, Fabiano Ferreira, João Henrique Costa-silva, Almir Goncalves WanderleyAbstract:Abstract Ethnopharmacological relevance The leaves of Persea Americana Mill. (Lauraceae) have been popularly used in the treatment of diabetes in countries in Latin America and Africa. Aim of the study To investigate the hypoglycaemic properties and to determine the molecular mechanism by which the hydroalcoholic extract of the leaves of Persea Americana reduce blood glucose levels in streptozotocin (STZ)-induced diabetes in rats via the enzymatic pathway of protein kinase B (PKB/Akt). Methods The hydroalcoholic extract of the leaves of Persea Americana (0.15 and 0.3 g/kg/day), vehicle and metformin (0.5 g/kg/day) were administered orally to STZ-diabetic rats (n = 7/group) for 4 weeks. Changes in body weight, food and water intake, fasting glucose levels and oral glucose tolerance were evaluated. Phosphorylation and the expression of PKB in the liver and soleus muscle were determined by Western blot. Results The hydroalcoholic extract of the leaves of Persea Americana reduced blood glucose levels and improved the metabolic state of the animals. Additionally, PKB activation was observed in the liver and skeletal muscle of treated rats when compared with untreated rats. Conclusion The results indicate that the hydroalcoholic extract of the leaves of Persea Americana has anti-diabetic properties and possibly acts to regulate glucose uptake in liver and muscles by way of PKB/Akt activation, restoring the intracellular energy balance.