Cofinite Graphs and their Profinite Completions

We generalize the idea of cofinite groups, due to B. Hartley. First we define cofinite spaces in general. Then, as a special situation, we study cofinite graphs and their uniform completions. The idea of constructing a cofinite graph starts with defining a uniform topological graph Gamma, in an appropriate fashion. We endow abstract graphs with uniformities corresponding to separating filter bases of equivalence relations with finitely many equivalence classes over Gamma. It is established that for any cofinite graph there exists a unique cofinite completion

Studies on adsorption of surfactants on solid-liquid interface and its importance in slurry-rheology

The knowledge of rheological properties for different materials for slurry preparation is of great importance. These topics are studied and severely important for several technical applications e.g. process control in chemical engineering, casting of ceramics, storage, transport of solids in pipelines and atomization. A literature on the change in rheological properties of coal water slurry is reviewed. The adsorption effect of surfactants like cationic, anionic and nonionic on the solid liquid interface is investigated. The rheological behaviors of kaolin-water slurry are experimented by using a rotational viscometer (Brookfield syncrolacto viscometer) with different solid concentrations. These experiments are conducted under a particular speed (in rpm) of the spindle, temperature and ph condition. The adsorption kinetics for the three different surfactants at their CMC values is studied for different amount of kaolin (in wt %) using a UV spectrophotometer. The cause of change in viscosity is investigated with the out coming results of the experiments and found that cationic and anionic surfactants affect the kaolin-water slurry rheology severel

Improvement of photocatalytic activity of Zinc Oxide nanoparticles using Zinc Sulphide Shell

Core/shell nanoparticles having distinct attributes of both core and shell have, of late, become attractive candidates for applications involving surface engineering of nanoparticles. In this work, the synthesis of ZnO/ZnS core/shell nanoparticles by wet chemical method is reported, formation of which is confirmed by HRTEM analysis. Characterization of the core/shell nanoparticles was done using absorption spectroscopy and HRTEM. ZnO/ZnS core/shell nanoparticles exhibited higher photocatalytic activity than the already proved good photocatalyst ZnO. This was supported by photocatalytic degradation experiments carried out on an organic dye, methylene blue, under direct sunlight irradiation. The enhancement in the photocatalytic activity is attributed to the increase of the surface reactivity of the as synthesized material, which is confirmed through the blue shift in the UV Visible absorption spectra. This material can be a promising photocatalyst in the field of water purification.Keywords: visible light, photocatalysis, ZnO, ZnO/ZnS Core/Shell, methelyne blu

Precalculus (University of North Georgia)

This Grants Collection for Introduction to Sociology was created under a Round Four ALG Textbook Transformation Grant. Affordable Learning Georgia Grants Collections are intended to provide faculty with the frameworks to quickly implement or revise the same materials as a Textbook Transformation Grants team, along with the aims and lessons learned from project teams during the implementation process. Documents are in .pdf format, with a separate .docx (Word) version available for download. Each collection contains the following materials: Linked Syllabus Initial Proposal Final Reporthttps://oer.galileo.usg.edu/mathematics-collections/1019/thumbnail.jp

Elementary Statistics (University of North Georgia)

This Grants Collection for Elementary Statistics was created under a Round Four ALG Textbook Transformation Grant. Affordable Learning Georgia Grants Collections are intended to provide faculty with the frameworks to quickly implement or revise the same materials as a Textbook Transformation Grants team, along with the aims and lessons learned from project teams during the implementation process. Documents are in .pdf format, with a separate .docx (Word) version available for download. Each collection contains the following materials: Linked Syllabus Initial Proposal Final Reporthttps://oer.galileo.usg.edu/mathematics-collections/1018/thumbnail.jp

Application of Soft Computing Techniques for Speed Control of Brushless DC Motors

Nowadays Brushless DC (BLDC) motors are treated as the most popular motors, which are applied widely due to their higher efficiency and excellent torque characteristics. Moreover they are operated with DC supply and without using brushes. But BLDC motor operate with wide speed range and therefore it is required to regulate the speed of DC motor using different advanced techniques. In this work, the fuzzy sliding mode control (FSMC) is employed for controlling the speed of BLDC motor. The proposed method is compared with the conventional Sliding mode control (SMC) and the results are analyzed using MATLAB/ Simulink tool