INTRODUCTION 1. INTRODUCTION 1.1 Fundamentals of capacitor Capacitor is very useful component in the field of engineering and it is used in various electrical and electronic circuitries. Capacitor stores energy in the form of electric field. Capacitor also known as condensers which stores energy when charge and release energy when discharge . There are different forms of capacitors which are used widely, but common thing about this all capacitors is that they are made of two conductors separated by single layer dielectric of uniform thickness .
If the wire is long and thin, when a current is sent through the wire a uniform magnetic field forms inside the solenoid. When the electric current flows through the wire the solenoid generates a magnetic field similar to that of a bar magnet. An electromagnet is a magnet whose magnetic properties are produced by an electric current. When the current is switched off, the electromagnet no longer displays magnetic properties. Another definition for electromagnets are solenoids wound around a central iron core.
This unzipping results in graphene ‘nanoribbons’, with ribbon widths dictated by the diameter of the tubes. Graphene nanoribbons are considered as quasi one dimensional material, and have different properties depending on their width and edge type (armchair/zigzag). Carbon nanotube unzipping occurs via C–C bond fission which is often initiated at defect sites, leading to irregular cutting. Recently the synthesis of well regulated nanoribbons has been demonstrated via unzipping of flattened carbon nanotubes, where attack occurs preferentially along the bent edges (Figure2.5). Producing graphene from carbon nanotubes is set to raise interesting questions as graphene is often seen as a replacement or alternative to
I. INTRODUCTION Different compounds can be classified based on the various chemical and physical properties such as solubility, conductivity, and melting point. Most of the chemical substances have unique features that allows sorting them to ionic, molecular, macromolecular and metallic compounds. Significantly, compounds divides into polar and non-polar, which can be checked by testing with polar and non-polar solvents. Electrical resistance related to the ability of the substance conduct electricity.
Each metallic bond has a general structure of metal ions and an electron cloud which has occurred due to the sea of valance electrons. This can be seen below in Figure 4. These free electrons are the reason metals are such good electric and thermal conductors. As there is different strength in the bonds the melting and boiling points vary according to this. The strength of the metals also varies based on the strength of the bond.
There are two types of electrodes: anode and cathode which are positively and negatively charged respectively. An electrolyte is a liquid or solution that can carry an electric current through it (BBC Bitesize). In solid form, sodium chloride can’t be electrolyzed as the ions are held and arranged in a lattice structure hence the ions are not mobile enough to move around. However, when solid sodium
Electrochemistry is the study of reactions in which charged particles (ions or electrons) appear in two phases of matter, such as the metallic phase (the electrode) or aqueous phase (the electrolyte). (Lower 2004) These reactions involve the transfer of electric charges between the electrodes and the electrolyte. These cells have two electrodes which are named the anode and the cathode. The anode is the electrode where oxidation occurs and the cathode is the electrode where reduction occurs (Electrochemical cells 2014). Oxidation always occurs simultaneously to reduction and the process of this electron transfer is named a redox reaction (A.Olivier 2010).