Scanning electron microscope

INTRODUCTION The science of magneto hydrodynamics (MHD) deals with geophysical, astrophysical and engineering problems since many years. This subject has attracted attention of many researchers in the MHD flow on Newtonian fluids on plate, cones and disks. Hari R [30] investigated the chemical and radiation effects on MHD casson fluid flow past an oscillating vertical plate embedded in porous medium. Subbaiah Naidu [70] studied the effect of Hall current on free convective flow of stratified…

Ligands have one electron pair to donate to a metal atom and are called complex agents. • Metal atoms are Lewis acids because they can accept pairs of electrons from Lewis bases. • Within a ligand, the atom that is directly bonded to the metal atom/ion is called the donor atom. • A coordinate covalent bond is a covalent bond in which one atom (i.e., the donor atom) gives both electrons. This type of bonding is different from a normal covalent bond in which each atom supplies one electron. • If…

observation cannot be explained by using Hooge’s relationship. 1.2.2 The McWhorter Model According to this model, fluctuations in the surface density of electrons, which results into fluctuation in conductivity, arise from exchange of electrons between the surface layer and traps lying in the oxide layer covering the surface. The transfer of electrons took place via tunneling. Since the tunneling probability decreases exponentially with separation between surface and trap, so does the…

negative magnetic source was near it. From the classical physics of Newtonian physics, he figured that opposites attract and likes repel. Since the cathode rays followed the similar approach, hence they were determined to be negatively charged or electrons. Therefore, using previously held theories, further discoveries can be made and new theories can supersede…

Electron motion in atomic systems, which happens on timescales of attoseconds, is at the heart of all phenomena in nature (except for nuclear processes). Electron motion is responsible for the emission of light and photosynthesis in plants. Electron motion across biological molecules transports information in our nerves and is involved in processing this information in our brains. Moreover, the valence electrons are responsible for binding atoms to form molecules. The structural change of…

How does an electric charge power a machine or make lights light up? The answer to all these questions begin with the basic building blocks of matter, the atom. Atoms are extremely tiny objects that are composed of even smaller particles: protons, electrons,…

we know them as electrons today. Thomson discovered that electrons are negatively charged, that they are much smaller and have less mass than atoms, and that they are uniformly present in many different types of substances. With this new discovery, the question of a balancing positive charge arose. Atoms are known to be charge-neutral, so it was believed that they must contain a positive charge that balanced the negative charge of the electron. Thomson proposed that the electrons, which are…

Critical assessment of the article: Quantitative analysis by Auger Electron Spectroscopy 1 Introduction When the outer electron fills the vacancy left by an ionized electron in the inner shell, the released energy can be passed to another outer electron that causes further emitting of an electron with characteristic energy, this is the basic principle of the Auger electron spectroscopy (AES) [1]. Nowadays, AES is almost an indispensable tool in nanoscience research for its high surface…

Heat conduction mechanism represents the energy loss at the particle surface due to the collisions with the surrounding gas molecules. There is no simple theory to explain the cooling mechanism of the particles. During the laser pulse, the particle achieves the peak temperature and emit thermal signal. After the laser pulse duration, the particle starts to cool down. The cooling of the particles is characterized by a decay function. The decay of LII signal provides information about the primary…

In the 1800s, chemist Michael Faraday discovered that water could be decomposed in an electrolytic solution into its elements. This discovery was made through the use of an electric current in a process now known as electrolysis. This was the first systematic study of electrolytic solutions (Lower, n.d.). Faraday observed that two requirements must be met in order for a sample of matter to be an electrical conductor. The first requirement is that the sample must contain electrically charged…