In this work, an experimental analysis is made to predict the thermal performance of the natural-convection phenomenon from a heated vertical externally finned-tube to surrounding air through an open-ended enclosure. Two different configurations of longitudinal rectangular fin namely, continuous and interrupted are utilized with constant thickness, different numbers, and different heights are extended radially on the outer surface of a heated tube. The tube is heated electrically from inner surface with five varied power input magnitudes. The effect of fins configuration, fins number, fins height, and heat flux of the inner tube surface on the thermal performance of natural convection have been studied and analyzed experimentally. Obtained results show that the tube with twelve interrupted longitudinal fins gives the best natural-convection thermal performance in terms of average Nusselt number, about 20% greater than that for the tube with continuous fins. Experimental correlations to predict the average Nusselt number for the heated tubes with continuous and interrupted longitudinal fins are proposed. The present data are compared to previous study and good convergence is noticed.
Novel artificial neural network (ANN) model was constructed for calibration of a multivariate model for simultaneously quantitative analysis of the quaternary mixture composed of carbamazepine, carvedilol, diazepam, and furosemide. An eighty-four mixing formula where prepared and analyzed spectrophotometrically. Each analyte was formulated in six samples at different concentrations thus twentyfour samples for the four analytes were tested. A neural network of 10 hidden neurons was capable to fit data 100%. The suggested model can be applied for the quantitative chemical analysis for the proposed quaternary mixture.
Biodiesel is becoming one of the most attractive alternative biofuels for petroleum-based diesel fuels. The castor plant is one of the abundant non-edible oils found in many countries. This paper aims to study Libyan castor oil and its potential for diesel conversion. Experiments were carried out in the laboratories of the Specific Center for Training in the Oil Industries in Al-Zawiya. The oil was extracted using a Soxhlet extractor and n-hexane solvent at 60 °C. Transesterification reactions were conducted in a batch reactor (a three-neck flask was used, where the middle opening carries a reflux condensation unit) at 65 °C. The methanol-to-castor oil molar ratio was 6:1, with a catalyst concentration of 1 wt.% relative to the ca
... Show MoreAn annotated list based both on personal collections and on literature records, is presented for twenty species and subspecies of Chrysomelinae from Iraq. Eight of which are newly recorded, bringing the total number of species and subspecies for Iraq to 25. Localities and host data are given for most species.
An essential component of food production is nitrogen (N). Crops waste about half of the nitrogen fertilizer input, which is then released into the atmosphere as gas emissions or polluting of aquatic groups. It is necessary to reach manufacture stages that promote world food security in the absence of compromising quality. safety of the environment. It is estimated that by 2050, N pollution levels will have risen 150% from 2010 levels, with the The agricultural sector is responsible for 60% of this growth. In this review fertilizer Nitrogen should take into account while discussing air pollution caused by gases that contain nitrogen, which might result in issues like the greenhouse effect. Nopoint pollution, the involvement of farme
... Show MoreAn essential component of food production is nitrogen (N). Crops waste about half of the nitrogen fertilizer input, which is then released into the atmosphere as gas emissions or polluting of aquatic groups. It is necessary to reach manufacture stages that promote world food security in the absence of compromising quality. safety of the environment. It is estimated that by 2050, N pollution levels will have risen 150% from 2010 levels, with the The agricultural sector is responsible for 60% of this growth. In this review fertilizer Nitrogen should take into account while discussing air pollution caused by gases that contain nitrogen, which might result in issues like the greenhouse effect . Nopoint pollution, the involvement of farmer manag
... Show MoreIn this study, the potential of adsorption of amoxicillin antibiotic (AMOX) from aqueous solutions using prepared activated carbon (AC) was studied. The used AC was prepared from an inexpensive and available precursor (sunflower seed hulls (SSH)) and activated by potassium hydroxide (KOH). The prepared AC was examined for its ability to remove AMOX from aqueous contaminated solutions and characterized with the aid of N2 -adsorption/desorption isotherm Brunauer–Emmett– Teller, scanning electron microscopy, energy-dispersive X-ray spectroscopy and Fourier-transform infrared. Zeta potential of the prepared activated carbon from sunflower seed hulls (SSHAC) were studied in relation to AMOX adsorption. The physical and chemical propert
... Show MoreThis research deals with an important grammatical section of the Qur'anic grammar, which is the working names the work of acts in the Quranic grammar in the studies of Iraqi researchers from 1968 to 200 AD.
The study of working names working verb in the Koran of the important studies, especially among Iraqi researchers, the Iraqi researcher has presented detailed studies related to working names particles action verb in the Koran, and my research is studying this important grammatical section of the Koranic grammar, which is the working names working verb in The Holy Quran in the books of Iraqi researchers and their theses from 1968-2000. I studied in the preface working names of the act, and what the Iraqi res