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The first and most important step in sample preparation for mass spectrometry is determining what phase the sample needs to be in. Different ionization methods require different sample phases. Solid phase samples can be ionized through methods such as field desorption, plasma-desorption, fast atom bombardment, and secondary-ion ionization.
In analytical chemistry, sample preparation (working-up) refers to the ways in which a sample is treated prior to its analyses. Preparation is a very important step in most analytical techniques, because the techniques are often not responsive to the analyte in its in-situ form, or the results are distorted by interfering species .
Atomic Absorption Spectroscopy (AAS) measures the concentration of specific elements in a sample by analyzing their unique "fingerprint" in the form of an atomic absorption spectrum. Here's how it works: Step 1: Sample Preparation:** The sample is typically dissolved in a suitable solvent (acids, water) to create a liquid solution.
In all three spectroscopic methods, the sample usually needs to be present in solution, which may present problems during forensic examination because it necessarily involves sampling solid from the object to be examined. In FTIR, three types of samples can be analyzed: solution , powder, or film. A solid film is the easiest and most straight ...
The analyte molecules in a sample can be partially ordered with respect to the external magnetic field of the spectrometer by manipulating the sample conditions. Common techniques include addition of bacteriophages or bicelles to the sample, or preparation of the sample in a stretched polyacrylamide gel. This creates a local environment that ...
The useful range for observation of a sample in a mid-infrared spectrum when using Fluorolube as the mulling agent is 4000 cm −1 to 1300 cm −1. [2] Because of these two agents’ complementary absorption processes, it is common to run a sample as both a Nujol mull and a Fluorolube mull separately.
This would be observable in a stress strain graph found through tensile testing. Sample preparation, including chain orientation within the sample, for tensile tests therefore can play a large role in the observed mechanical properties. The fracture properties of crystalline and semicrystalline polymers can be evaluated with Charpy impact ...
To qualitatively determine which elements exist in a sample, the methods are mass spectrometric atomic spectroscopy, such as inductively coupled plasma mass spectrometry, which probes the mass of atoms; other spectroscopy, which probes the inner electronic structure of atoms such as X-ray fluorescence, particle-induced X-ray emission, X-ray ...