Chemical ionization , mass description

Gas-phase acid-base studies are usually performed by using one of the following techniques high-pressure mass spectrometry (HPMS), chemical ionization mass spectroscopy (CIMS) with mass-analysed ion kinetic energy spectroscopy/collision induced dissociation (MIKES/CID), flowing afterglow (FA) or ion cyclotron resonance (ICR) spectrometry. For a brief description of all methods, Reference 8 should be consulted. 

The term nebulizer is used generally as a description for any spraying device, such as the hair spray mentioned above. It is normally applied to any means of forming an aerosol spray in which a volume of liquid is broken into a mist of vapor and small droplets and possibly even solid matter. There is a variety of nebulizer designs for transporting a solution of analyte in droplet form to a plasma torch in ICP/MS and to the inlet/ionization sources used in electrospray and mass spectrometry (ES/MS) and atmospheric-pressure chemical ionization and mass spectrometry (APCI/MS). 

A detailed description of sources used in atmospheric pressure ionization by electrospray or chemical ionization has been compiled.2 Atmospheric pressure has been used in a wide array of applications with electron impact, chemical ionization, pressure spray ionization (ionization when the electrode is below the threshold for corona discharge), electrospray ionization, and sonic spray ionization.3 Interferences potentially include overlap of ions of about the same mass-charge ratio, mobile-phase components, formation of adducts such as alkali metal ions, and suppression of ionization by substances more easily ionized than the analyte.4 A number of applications of mass spectroscopy are given in subsequent chapters. However, this section will serve as a brief synopsis, focusing on key techniques. 

This book describes the fundamental operating characteristics of the most common inorganic mass spectrometers. At the heart of this discussion is a description of the various ionization sources that generate a representative analyte population for mass analysis. The initial chapters introduce the mass spectrometric hardware that separates the ionized fractions of analytes, one mass from another. The detection schemes used to measure this ion population, and the data processing systems that permit this information to be of value to the chemical analyst, are also discussed. 

Step), and leave the reaction area into bulk solution (second mass transfer). The mass transfer step, as well as the electrochemical one, are always present in any electrochemical transformation. Importantly, the electrochemical step is always accompanied by transfer of a charged particle through the interface. That is why this step is called the transfer step or the discharge-ionization step. Other complications are also possible. They are related to the formation of a new phase on the electrode (surface diffusion of adatoms, recombination of adatoms, formation of crystals or gas bubbles, etc.). The transfer step may be accompanied by different chemical reactions, both in bulk and on the electrode surface. A set of all the possible transformations is called the electrode process. Electrochemical kinetics works with the general description of electrode processes over time. While related to chemical kinetics, electrochemical kinetics has several important features. They are specific to the certain processes, in particular - the discharge-ionization step. Determination of a possible step order and the slowest (rate-determining) step is crucial for the description of the specific electrode process. 

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