Pulse liquid atomization

The atom probe field-ion microscope (APFIM) and its subsequent developments, the position-sensitive atom probe (POSAP) and the pulsed laser atom probe (PLAP), have the ultimate sensitivity in compositional analysis (i.e. single atoms). FIM is purely an imaging technique in which the specimen in the form of a needle with a very fine point (radius 10-100 nm) is at low temperature (liquid nitrogen or helium) and surrounded by a noble gas (He, Ne, or Ar) at 10 -10 Pa. A fluorescent screen or a... 

The incident ions cause recoil in the surface atoms. In studies of ionic liquids, only direct recoil - that is, motion in the forward direction - was measured. Watson and co-workers [56, 57] used time-of-flight analysis with a pulsed ion beam to measure the kinetic energies of the scattered and sputtered ions and therefore determine the masses of the recoiled surface atoms. By relating the measured intensities of the... 

Measurement techniques that can be employed for the determination of trace metals include atomic absorption spectrometry, anodic stripping voltammetry, differential pulse cathodic stripping voltammetry, inductively coupled plasma atomic emission spectrometry, liquid chromatography of the metal chelates with ultraviolet-visible absorption and, more recently, inductively coupled plasma mass spectrometry. 

Plain-orifice atomizers are widely used for injecting liquids into a flow stream of air or gas. The injection may occur in a co-flow, a contra-flow, or a cross-flow stream. The best known application of plain-orifice atomizers is perhaps diesel injectors. This type of injectors is designed to provide a pulsed or intermittent supply of fuel to the combustion zone for each power stroke of the piston. As the air in the combustion zone is compressed by the piston to a high pressure, a very high pressure (83-103 MPa) is required to allow the fuel to penetrate into the combustion zone and disintegrate into a well-atomized spray. 

This technique for the study of a fast reaction is gas phase or liquid phase was developed by Norrish and Poster. This is an example of Pulse method which initiates a reaction by creating new reactive species—excited electronic states, radicals, ions in the system under study. The method uses a light flash of high intensity for a very short duration (10- s) to produce atoms or free radicals or excited species in a system. These are at a fairly high concentration and undergo further reactions which are followed spectroscopically. A spectroscopic flash of light is followed by the initial flash by some fraction of a millisecond. The absorption spectra of all the species that are formed within the system can be recorded. One cannot only get indications of what species are formed but also how these species give rise to others. Thus a very direct picture of the kinetic behaviour of a fast reaction can be obtained. 

If a rapid, reciprocating motion of relatively short amplitude is applied to the liquid contents of an extraction column, the column is said to be pulsed. The agitation thus provided has been found to give improved extraction rates. Devices of this sort were suggested as early as 1935 (VI), but it was not until the atomic energy programs in the United States and Great Britain developed a need for efficient extractors of low... 

The molecules that are dissociated and the atoms that are ionized during plasma production can be in any state at the start. Steady-state plasmas are formed most often from gases, although liquids, such as volatile organics, and solids are also used. Gases and solids routinely serve as sources of material in pulsed plasma work. 

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