How to use datedif function of excel?

Datedif function in excel is used to calculate the difference in date and expressed either in years or months or both. If you want to find the age of man born on say 9/20/1998 and the current date or date of survey is 6/15/2014. To find out his age in year and month in excel using datedif function,call for the following function =DATEDIF(A1,B1,"y")&"."&DATEDIF(A1,B1,"ym") if you want to express the age in year and month both. In the example below, 15.8 means the man is 15 years and 8 months old. similarly if you want to express the age only in month then call for the following function in excel =datedif(a1,b1,"m") In the example below, 188 means the man is 188 months old. Additionally if you just want to round up with the age expressed in years call for the following function in excel =datedif(a1,b1,"y") In the example below, the numeric value in e1 indicate the age of the man and this figure is rounded only for the number of years.

Hope this will help you to solve your problem related to age calculation in excel. Thank you

NMR spectroscopy

 NMR

Nuclear magnetic resonance spectroscopy (NMR) is basically another form of absorption spectroscopy. Under appropriate condition in a magnetic field a sample can absorb electromagnetic radiation in the radiofrequency region, as frequencies being governed by the characteristic sample. Absorption is a function of certain nuclei in the molecule. A plot of the frequencies of the avsorption peaks versus peak intensities constitutes an NMR spectrum. NMR is a powerful tool for the investigation of molecular structure.

A hydrogen nucleus may have a clockwise (+1/2) or anticlockwise (-1/2) spin and the nuclear magnetic moment μ in the two cases are in the opposite direction. In an applied magnetic field, all protons have their magnetic moment either aligned with the field or opposed. The two spin state of hydrogen atom +1/2 is at lower energy since it aligned with the applied magnetic field while the spin state -1/2 is of higher energy state since it opposes the applied magnetic field.

Reasons for taking tetramethylsilane (TMS) as a reference compound
1. TMS has 12 equivalent protons and gives an intense single signal.
2. The electronegativity of silicon is very low as compared to carbon as a result of this the shielding of equivalent proton in TMS is more than that of almost all organic compound.
3. TMS is chemically inert and has a very low boiling point (300K) so that it can easily be evaporated after the spectrum has been recorded.
4. TMS is not soluble in aqueous solution.
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NMR 

Electrophoresis

Electrophoresis

Introduction

Electrophoresis is the motion of dispersed particles relative to a fluid under the influence of a spatially uniform electric field. It is a technique that describes the migration of charge particles under the influence of an electrical field. This technique is mainly applied for the analysis of macromolecules like amino acids, peptides, proteins and nucleic acid since these possess ionisable groups. 

The sample material must be dissolved or suspended in buffer for electrophoresis to take place and the supporting medium must also be saturated with the buffer in order to conduct the current. If the buffer used is at a pH above that of the isoelectric point of the molecule, the sample will be negatively charged and under the influence of the electric field it will migrate toward the anode and if buffer used is at pH below the isoelectric point of the molecule it will be positively charge and eventually migrate towards the cathode.  

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https://sites.google.com/site/gkrishnakharells/instrumental-technique-of-analysis