Physical Sciences and Engineering

In recent years, global energy systems have undergone a transition, with their energy matrices gradually shifting towards more renewable and cleaner sources. Among the various alternative energy sources, biofuels have become the subject of extensive academic research and scientific studies. The aim of this paper is to utilize jackfruit seeds, an agro-industrial residue, to obtain biofuel using the transesterification method. The oil was extracted from the seeds using the Soxhlet Extraction method, with hexane as the solvent.

Conservation and non-conservation are two aspects of extensive quantities. Current physics textbooks deal with conservation and non-conservation in some ways that, unfortunately, lead to misunderstandings of extensive quantities. In this paper, we will discuss and explain how this is inappropriate or obsolete and we will make some suggestions for teaching conservation and non-conservation of extensive quantities and finally give a clear and simple formulation for each extensive quantity.

Our objective for this work is to study natural convection in a cavity differentially heated in 3D. The equations which govern our problem are expressed in a dimensionless form with a calculation procedure based on the finite element method implemented in the COMSOL Multiphysics calculation code. The flow is unsteady turbulent flow. Several numerical studies have been carried out in parallelepiped cavities using the Boltzmann lattice method.

This review embodies the theoretical investigation of three types of problems viz., a general model for the Technique of Reconstitution, Penetrative convection in fluid and porous layers under different constraints like, rotation, salinity gradient, nonlinear temperature profile etc., and thermosolutal instability in homogenous and heterogeneous layers in the presence of coupled molecular diffusion.The aim of the present investigation is to provide the qualitative as well as the quantitative features of the phenomena e.g.

Oil was extracted from tiger nut (Cyperus esculentus) tubers at a percentage oil yield of 4.72% using Soxhlet extraction method. The extracted oil was characterized using Gas Chromatography Flame Ionization Detector (GC-FID) and a fatty acid percentage composition of 35.69%, 20.78%, 18.03%, 14.25%, 9.35%, and 1.90% of Oleic acid, Linolenic acid, Lauric acid, Myristic acid, Linoleic acid and Eicosapentaenoic acid respectively was obtained, giving a total percentage fatty acid composition of 100%.

Sustainable agriculture performs a significant part in agroecosystems and decline destructive consequences at the environment through making use of multiple natural processes. Optimum soil fertility is a crucial purpose to be executed in sustainable agriculture system. Arbuscular mycorrhizal fungi (AMF) execute an environmental-friendly way to accomplish the previous objectives. Most of the terrestrial plant species are associated with the AMF and they have a necessary mutualistic link with plants.

Aim & In this paper, we introduce the third system which is called the category of natural deduction (CND) for language propositional logic system(LPLS), it's essential different in its form and ways form truth -table and truth-tree for (LPLS), even itspick out (or select) the same symbolic language like that used in the system of truth-table and truth- tree for (LPLS).

Nigeria he interest in biometric technology is received much attention in the recent years. However, the security issue still persists the main challenge for the reliable functioning of biometric authentication systems (BAS). Much academic research has been reported on the vulnerabilities of biometric systems that breach the se-curity and user privacy in mobile devices. We present a high-level classication of taxonomy of attacks against BAS and discuss the severity of attacks on the BAS for mobile computing device.

Made n- and p-type Si0.7Ge0.3 thermoelectric alloys and their thermoelectric characteristics are studied. These alloys are cut into profiled plates, monolithic packages are assembled from them, switching plates are glued to the lower and upper bases of the packages, commutated packages are cut into 4-5 mm thick plates and monolithic thermoelectric modules are assembled from them. Electrical insulation nodes of thermoelectric modules are made on the basis of AlN and graphite plates. These nodes are connected to modules, resulting in monolithic samples.

An experimental study was carried out on an indirect solar dryer operating with natural convection. The study focused on the behavior of three parameters over time. Solar radiation at the measurement site, the temperature of various elements of the collector and of the air at four precise locations inside the dryer, and the velocity at its outlet were measured. The results of the five-day average measurements showed that the solar dryer has a uniform temperature profile inside the drying chamber.