Essays on Scanning Electron Microscope

Raman spectroscopy is dependent on scattering of light. When light interacts with matter, energy exchange can take place through absorption, simulated emission, Raman scattering or spontaneous emission. In Raman scattering, the emitted photons have less energy and lower frequency in comparison with the absorbed photons. Some energy of the emitted photons is transferred to the molecules. Raman spectroscopy is a method which collects the chemical fingerprints associated with molecules. Every molecule has different levels of vibrational energy and the emitted photons experience shift in their wavelengths. The wavelength shifts are collected,examined and analyzed for sample identification. Raman spectroscopy ...

Introduction

There are different perspectives that are being peddled concerning fracture processes, this has led to confusion on what actually this term means. In this review, a deeper understanding is sort by analyzing different aspects of the nomenclature of the fracture process. In order to gain a deeper understanding of the failure processes several aspects are put in consideration key among them will be discussed below and include; the energy of fracture, macroscopic structure path and microscopic fracture mechanisms.

Energy to Break

The toughness of a material is the measure of the absorbed energy during and before fracture. The toughness of the material ...

Scanning electron microscope uses a beam of electrons to form images that reveal the topography and composition of a body. Before being focused on the object, incident electrons have high amounts of kinetic energy. Incident electrons interact with the surface of the specimen, and this interaction is determined by the rate of the acceleration of the incident electrons. Energetic electrons are usually released from the surface of the sample when the incident electrons come into contact with it. The interaction results in the formation of scatter patterns that interpret into the shape, composition, size, and texture of the specimen. ...

- Introduction A compound light microscope represents two or more lens. The term compound refers to multiple or mixture. In compound light microscope built with binocular lens and objective lens. The binocular lens present near the eyepiece and objective leans near to nosepiece. The objective lens helps in enlargement of images and also to collect the light source. According to the requirement the objective lens also changes. In advanced compound light microscope the phase contrasts also possible. In earlier 1595 Zacharias Janssen invented the first light microscope using collapsing tubes. It produced a magnification of 9x. Now the magnification ...

Introduction

The microscope is derived from two Greek words, mikros and skopeo. Mikros means small while skopeo means “look at.” Thus, the two words form the word mikroskopeo that refers to looking or observing small objects. Since the beginning of scientific developments, there has been an interest to look at the smaller details of the world around us. Biologists have taken the lead in the quest to uncover such small details through their desire to examine cells, viruses, bacteria, and colloidal particles. Material scientists have wanted to observe the limitations and inhomogeneities in metals, ceramics, and crystals. Geologists have also ...

Electron microscopes refer to those microscopes that make use of an electron beam to light a specimen producing a magnified image. These microscopes are used to study structures that are either invisible through naked eyes or those that are too small to be clearly seen using a light microscope. The two major types of electron microscope are Transmission Electron Microscopy or TEM and Scanning Electron Microscopy or SEM (Mooney, 1996). Transmission Electron Microscopy employs a high voltage electron beam in order to create an image (NE, 2013). The TEM is made up of various components including electromagnetic lens system, electron source, sample ...