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IR Spectroscopy: Definition, Instrumentation, Working and Applications

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What is IR Spectroscopy? Infrared spectroscopy is absorption spectroscopy that deals with the recording of the absorption of the electromagnetic radiations of the infrared region of the electromagnetic spectrum. The IR region ranges from 700-1000 nm.   This technique is widely used for the detecting of functional groups, characterization of proteins, analysis of various liquids, and identification of molecules and their composition. Instrumentation of IR spectroscopy 1. Radiation source The radiation source should emit IR electromagnetic radiations which are steady, intense, and extended over the desired wavelength. That's why radiation sources like Nernst glower, globar source, incandescent lamp, and mercury arc lamp. 2. Monochromator It helps to select desired frequencies of IR radiations because our sample will only absorb some specific frequencies of IR radiations. Prism and grating are the most commonly used monochromators. 3. Sample cells and sampling IR spectroscopy is ...

U.V-Visible spectroscopy: Instrumentation, Working and Applications

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What is U.V-Visible spectroscopy? U.V-Visible spectroscopy is absorption spectroscopy that deals with the recording of the absorption of electromagnetic radiation of the U.V and Visible regions of the electromagnetic spectrum. The U.V-region ranges from 200-400 nm whereas the visible region ranges from 400 to 800 nm.   So, we can say that U.V-Visible spectroscopy utilizes a 200-800 nm range for working. This technique is widely used for detecting the presence and elucidating the nature of the conjugated multiple bonds and aromatic rings. Instrumentation of U.V-Visible spectroscopy 1. Radiation source Hydrogen-discharge lamp is the most commonly used source of radiation in the U.V region (200-400 nm) whereas a deuterium-discharge lamp is used when more intensity (3-5 times) is desired. A tungsten-filament lamp is used when absorption in the Visible region (400-800 nm) is to be determined. 2. Monochromator It helps to separate the radiations into separate wavelengths that are it...

Forensic Anthropology: Definition, History and Application

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What is Forensic Anthropology? Forensic anthropology is a specialized branch of physical anthropology that deals with the medico-legal purpose to establish the identity of the deceased person. It uses the knowledge of human anatomy like the size of bones, hairs, length, features of bones, teeth, etc to determine the person's age, sex, stature, and race. In some cases, it can also predict the cause of death of the person by studying the different features on the bone. Forensic anthropologists are often called to the scene of the crime to study the remains of human remains which got decomposed, burned, mutilated, or difficult to recognize. Forensic anthropology can be used in accident cases like aircraft crashes, arson, fire accidents, genocide, etc. History of Forensic Anthropology The history of forensic anthropology dates back to the 19th century when anatomists were often asked for human identification through their skeletal. In 1835, Mathieu Orfila , a french forensic medicine ...