Saha function

These expressions for the intensities contain three factors that depend on the temperature, namely the degree of ionization, the Boltzmann factors and the partition functions. In particular, ay can be written as a function of the electron number density and the Saha function as ... 

However, the latter is also given by the well-known Saha equation. With the aid of wave mechanics and through differentiation of the Boltzmann equation, the Saha function in terms of the partial pressures can also be expressed as ... 

Thoren, S., Weinander, R., Saha, S. et al. Human microsomal prostaglandin E synthase-1 purification, functional characterization, and projection structure determination. /. Biol. Chem. 278 22199-22209,2003. 

At high temperatures, the rates have to be summed over relevant nuclear states and the (2/ + 1)-factors in Saha s equation replaced by partition functions. 

Saha S (2009) Soil functions and diversity in organic and conventional farming. A review. In Lichtouse E (ed) Sustainable agriculture reviews, vol 3. Springer, pp 41-76. In press. This volume... 

In a simultaneous attempt to screen for further non-hydroxamate ZBGs, this team focussed on potentially bidentate ZBGs and identified a SAHA-like compound with a mercaptoacetamide functionality, which had an HDAC enzyme... 

Figure 4. Efficiency of ionization as described by Saha s law as a function of the ionization potential for a representative electronic density of 10 m". The ionization potentials of some elements for which the isotopic composition is commonly analyzed are shown at the top.

Saha, S., and Hamaguchi, H., Effect of water on the molecular structure and arrangement of nitrile-functionalized ionic liquids, /. Phys. Ghem. B, 110, 2777-2781, 2006. 

This is the famous Saha-Langmuir equation. In it, g+/g0 is the ratio of the statistical weights of the ionic and atomic states, is the work function of the surface, / is the first ionization potential of the element in question, k is the Boltzmann constant, and T is the absolute temperature. Note that gjg0 is close to 1 for electronically complex elements for simpler elements it can take on a variety of values depending on how many electronic states can be populated in the two species for alkali atoms, for example, it is often Vi. Attainment of thermodynamic equilibrium was assumed in the derivation of this equation, and it is applicable only to well-defined surfaces. 

The Saha-Langmuir equation has been used to obtain both ionization potentials [25] and work functions [26]. Measuring ion beam intensities at several different temperatures and plotting their logarithms vs. 1/7" yield a straight line whose slope is ( - f)/k. If either or / is known, the other is readily calculated. Hertel introduced a method of measuring ionization potentials that was independent of the work function of the surface, using instead as reference an element of known ionization potential he applied it in the determination of the first ionization potentials of the lanthanide elements [27]. 

In addition to the statistical mechanical temperatures, a distribution temperature, called the ionization temperature, and defined by the Saha equation, is frequently referred to (D2, S3). In its simplest form—for a monatomic gas—the Saha equation states that the equilibrium established between the species present [positive ions (+), electrons (e), and neutral atoms (0) ] is a function of temperature,... 

Table II. Fraction of Ionized Particles as a Function of Their Diameter (Da) and Electron Concentration n ), Computed by Using the Saha Equation...

Figure 3 Histone deacetylase inhibitors, (a) The mechanism by which many HDAC inhibitors function. A hydrophobic moiety biocks the active site of the HDAC. A fiexibie iinker extends into the cieft, and a poiar group interacts with the active zinc atom, (b) Crystai structure of TSA (ieft) and SAHA (right) in the active site of a HDAC-iike protein HDLP (87). (c) Exampies from four major ciasses of HDAC inhibitors.

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