Rheological characteristics of aluminium oxide (AL2O3) based nanolubricant

This paper presents the rheological measurement of aluminium oxide (Al2O3) nanolubricant. The nanolubricant was prepared using the two-step method from dry Al2O3 nanoparticles and Capella D lubricant as base fluid. The dynamic viscosity of the Al2O3 nanolubricant at constant shear rate was measured at atmospheric pressure in the temperature range of 278 K to 323 K for pure based lubricant along with nanolubricant mass concentration of 1%, 2% and 4% with nanoparticle size of 10 nm, 20-30 nm and 80 nm. The measured data was analysed using the linear fit and exponential function fit. The result showed that at constant particle size and concentration, the dynamic viscosity reduces with increase in temperature while at constant temperature, the viscosity increased with nanoparticle concentration. The exponential function fit regression best describe the relationship between the viscosity and temperature when compared with the linear fit regression while the polynomial function fit best describe the relationship between the viscosity and mass concentration. Keywords: Dynamic viscosity, nanolubricant, shear rate, regression, concentration, temperatur

Experimental Studies of Effects of Geometry on Drying Rate and Properties of Ginger (Zingiber officinale Rosc.) with Solar-hybrid Dryer

Poor drying and processing methods employed by Nigerian farmers have led to loss of quality of dried ginger produced. Therefore, there is need to improve the drying and processing methods so that the quality of the products will be improved. To achieve this, a natural convection solar dryer was designed and constructed to dry ginger slices in different geometries. A 3 kg capacity hybrid dryer which was solar and biomass fueled was designed. The ginger samples were grouped into peeled and unpeeled. The specimens (peeled and unpeeled) were cut into cylindrical (Ø 0.2 m, thickness 0.008 m) and rectangular (0.03 x 0.025 m, thickness 0.008 m) shapes and 2.7 kg each were dried using open air, solar assisted and hybrid dryer. The initial and final moisture contents considered were 82.3% and 10% (wet basis), respectively. The average ambient conditions were 30 ºC air temperature and 15% relative humidity with daily global solar radiation incident on horizontal surface of about 20MJ/m2 /day. The weather conditions considered are of Ogbomoso, Nigeria. A prototype of the dryer is so designed and constructed that has a maximum collector area of 1.03m2. The percentage essential oil retention of cylindrical was higher than that of rectangular. Keywords: Solar biomass dryer, Ginger, geometry, drying, essential oil Radiatio

Assessing the emission factors of low-pour-fuel-oil and diesel in steam boilers

The purpose of this study is to examine the emissions effects resulting from the use of low pour fuel oil (LPFO) and diesel fuels in industrial steam boilers operation. The method of ultimate analysis of the products of combustion and emissions of pollutant analysis were used to estimate the annual rate of emissions of boilers. The results shows that the levels of uncontrolled boiler emissions on the environment can lead to increased greenhouse effects, global warming, and pollution and toxilogical impacts on human health. Only carbon monoxide emission was found to vary with the levels of oxygen generation in the products of combustion, while other substances were generally in relation to constituents and rates of consumption of fuel

Nonlinear Vibration Analysis of Thermo-Magneto-Mechanical Piezoelectric Nanobeam Embedded in Multi-Layer Elastic Media based on Nonlocal Elasticity Theory

The present article focuses on the investigations of electromechanical thermo-magnetic coupled effects on the nonlinear vibration of single-walled carbon nanobeam embedded in Winkler, Pasternak, quadratic and cubic nonlinear elastic media for simply supported and clamped boundary conditions are investigated. From the parametric studies, it is shown that the frequency of the nanobeam increases at low temperature but decreases at the high temperatures. The nonlocal parameter decreases the frequencies of the piezoelectric nanobeam. An increase in the quadratic nonlinear elastic medium stiffness causes a decrease in the first mode of the nanobeam with clamped-clamped supports and an increase in all modes of the simply supported nanobeam at both low and high temperature. When the magnetic force, cubic nonlinear elastic medium stiffness, and amplitude increase, there is an increase in all mode frequency of the nanobeam. A decrease in Winkler and Pasternak elastic media constants and increase in the nonlinear parameters of elastic medium results in an increase in the frequency ratio. The frequency ratio increases as the values of the dimensionless nonlocal, quadratic and cubic elastic medium stiffness parameters increase. However, the frequency ratio decreases as the values of the temperature change, magnetic force, Winkler and Pasternak layer stiffness parameters increase. An increase in the temperature change at high temperature reduces the frequency ratio but at low or room temperature, increase in temperature change, increases the frequency ratio of the structure nanotube. This work will greatly benefit in the design and applications of nanobeams in thermal and magnetic environments

Nonlinear Vibration Analysis of Thermo-Magneto-Mechanical Piezoelectric Nanobeam Embedded in Multi-Layer Elastic Media based on Nonlocal Elasticity Theory

The present article focuses on the investigations of electromechanical thermo-magnetic coupled effects on the nonlinear vibration of single-walled carbon nanobeam embedded in Winkler, Pasternak, quadratic and cubic nonlinear elastic media for simply supported and clamped boundary conditions are investigated. From the parametric studies, it is shown that the frequency of the nanobeam increases at low temperature but decreases at the high temperatures. The nonlocal parameter decreases the frequencies of the piezoelectric nanobeam. An increase in the quadratic nonlinear elastic medium stiffness causes a decrease in the first mode of the nanobeam with clamped-clamped supports and an increase in all modes of the simply supported nanobeam at both low and high temperature. When the magnetic force, cubic nonlinear elastic medium stiffness, and amplitude increase, there is an increase in all mode frequency of the nanobeam. A decrease in Winkler and Pasternak elastic media constants and increase in the nonlinear parameters of elastic medium results in an increase in the frequency ratio. The frequency ratio increases as the values of the dimensionless nonlocal, quadratic and cubic elastic medium stiffness parameters increase. However, the frequency ratio decreases as the values of the temperature change, magnetic force, Winkler and Pasternak layer stiffness parameters increase. An increase in the temperature change at high temperature reduces the frequency ratio but at low or room temperature, increase in temperature change, increases the frequency ratio of the structure nanotube. This work will greatly benefit in the design and applications of nanobeams in thermal and magnetic environments

On the Classification of Gasoline-fuelled Engine Exhaust Fume Related Faults Using Electronic Nose and Principal Component Analysis

The efficiency and effectiveness of every equipment or system is of paramount concern to both the manufacturers and theend users, which necessitates equipment condition monitoring schemes. Intelligent fault diagnosis system using patternrecognition tools can be developed from the result of the condition monitoring. A prototype electronic nose that uses array ofbroadly tuned Taguchi metal oxide sensors was used to carry out condition monitoring of automobile engine using itsexhaust fumes with principal component analysis (PCA) as pattern recognition tool for diagnosing some exhaust relatedfaults. The results showed that the following automobile engine faults; plug-not-firing faults and loss of compression faultswere diagnosable from the automobile exhaust fumes very well with average classification accuracy of 91%.Key words: Electronic nose, Condition Monitoring, Automobile, Fault, Diagnosis, PCA

Brief/Short Communication: New Record of Culex Poicilipes from Saudi Arabia (Jazan Region)

This record represents the first report for adult Culex poicilipes from Saudi Arabia (a farm near Albahir village of Sabya Governate, Jazan region southwest of Saudi Arabia, N: 42.58810, E:17.121738) was noted. This was occurred during a routine surveillance for adult mosquitoes in February 2021 carried out by Sabya vector control station and the laboratory of vector-borne diseases, Saudi Public Health Authority. With this new record, the number of Culex mosquito species known to occur in Jazan region increases to 19 while for Saudi Arabia to 20. Similarly, the total number of mosquito species known to occur in Saudi Arabia increases to 50.This record necessitates conducting more researches on the biology and bionomics of Culex poicilipes under local conditions, as well as complementing the morphological identification with molecular characterizations and gene diversity. The possible role of the species in pathogens transmission, especially West Nile and Rift Valley fever viruses, should also be investigated. Keywords: Culex poicilipes, New record, Saudi Arabia, Jazan region DOI: 10.7176/JEES/11-4-03 Publication date: April 30th 202

Alleviation of Boron Stress through Plant Derived Smoke Extracts in Sorghum bicolor

Boron is an essential micronutrient necessary for plant growth at optimum concentration. However, at high concentrations boron affects plant growth and is toxic to cells. Aqueous extract of plant-derived smoke has been used as a growth regulator for the last two decades to improve seed germination and seedling vigor. It has been established that plant-derived smoke possesses some compounds that act like plant growth hormones. The present research was the first comprehensive attempt to investigate the alleviation of boron stress with plant-derived smoke aqueous extract on Sorghum (Sorghum bicolor) seed. Smoke extracts of five plants, i.e. Cymbopogon jwarancusa, Eucalyptus camaldulensis, Peganum harmala, Datura alba and Melia azedarach each with six dilutions (Concentrated, 1:100, 1:200, 1:300, 1:400 and 1:500) were used. While boron solutions at concentrations of 5, 10, 15, 20 and 25 ppm were used for stress. Among the dilutions of smoke, 1:500 of E. camaldulensis significantly increased germination percentage, root and shoot length, number of secondary roots and fresh weight of root and shoot while, boron stress reduced growth of Sorghum. It was observed that combined effect of boron solution and E. camaldulensis smoke extract overcome inhibition and significantly improved plant growth. Present research work investigated that the smoke solution has the potential to alleviate boron toxicity by reducing the uptake of boron by maintaining integrity of plant cell wall. The present investigation suggested that plant derived smoke has the potential to alleviate boron stress and can be used to overcome yield losses caused by boron stress to plants

Mapping subnational HIV mortality in six Latin American countries with incomplete vital registration systems

BackgroundHuman immunodeficiency virus (HIV) remains a public health priority in Latin America. While the burden of HIV is historically concentrated in urban areas and high-risk groups, subnational estimates that cover multiple countries and years are missing. This paucity is partially due to incomplete vital registration (VR) systems and statistical challenges related to estimating mortality rates in areas with low numbers of HIV deaths. In this analysis, we address this gap and provide novel estimates of the HIV mortality rate and the number of HIV deaths by age group, sex, and municipality in Brazil, Colombia, Costa Rica, Ecuador, Guatemala, and Mexico.MethodsWe performed an ecological study using VR data ranging from 2000 to 2017, dependent on individual country data availability. We modeled HIV mortality using a Bayesian spatially explicit mixed-effects regression model that incorporates prior information on VR completeness. We calibrated our results to the Global Burden of Disease Study 2017.ResultsAll countries displayed over a 40-fold difference in HIV mortality between municipalities with the highest and lowest age-standardized HIV mortality rate in the last year of study for men, and over a 20-fold difference for women. Despite decreases in national HIV mortality in all countries-apart from Ecuador-across the period of study, we found broad variation in relative changes in HIV mortality at the municipality level and increasing relative inequality over time in all countries. In all six countries included in this analysis, 50% or more HIV deaths were concentrated in fewer than 10% of municipalities in the latest year of study. In addition, national age patterns reflected shifts in mortality to older age groups-the median age group among decedents ranged from 30 to 45years of age at the municipality level in Brazil, Colombia, and Mexico in 2017.ConclusionsOur subnational estimates of HIV mortality revealed significant spatial variation and diverging local trends in HIV mortality over time and by age. This analysis provides a framework for incorporating data and uncertainty from incomplete VR systems and can help guide more geographically precise public health intervention to support HIV-related care and reduce HIV-related deaths.Peer reviewe

Anemia prevalence in women of reproductive age in low- and middle-income countries between 2000 and 2018

Anemia is a globally widespread condition in women and is associated with reduced economic productivity and increased mortality worldwide. Here we map annual 2000–2018 geospatial estimates of anemia prevalence in women of reproductive age (15–49 years) across 82 low- and middle-income countries (LMICs), stratify anemia by severity and aggregate results to policy-relevant administrative and national levels. Additionally, we provide subnational disparity analyses to provide a comprehensive overview of anemia prevalence inequalities within these countries and predict progress toward the World Health Organization’s Global Nutrition Target (WHO GNT) to reduce anemia by half by 2030. Our results demonstrate widespread moderate improvements in overall anemia prevalence but identify only three LMICs with a high probability of achieving the WHO GNT by 2030 at a national scale, and no LMIC is expected to achieve the target in all their subnational administrative units. Our maps show where large within-country disparities occur, as well as areas likely to fall short of the WHO GNT, offering precision public health tools so that adequate resource allocation and subsequent interventions can be targeted to the most vulnerable populations.Peer reviewe