Energy linear

Modulation of the Killing of Mammalian Cells by Thiols. Important aspects of the effects of exogenous thiols on clonogenic cell survival following exposure to low linear energy transfer (LET) radiations include the following. 

The hydrogen bond of sulphoxides and linear energy relationships. 552... 

These results clearly demonstrate that linear energy relationships can be established for the formation of hydrogen bonds between numerous Lewis bases (including sulphoxides) with Lewis acids. 

Recently, Kamlet and Taft introduced new elaborate parameters in order to explain the linear energy relationship for the formation of the hydrogen bond between HBA (hydrogen bond acceptor) and HBD (hydrogen bond donor). They treated several sulphoxides as HBA. The detailed presentations and actual treatments of these parameters have been described in their recent review article72. 

They have also demonstrated that a linear energy relationship exists between pKa values of sulphoxides and the hydrogen bonding ability which was determined by IR-stretching shift of the OH band in PhOH in CC14. Oae and coworkers173 determined the pKa values of diaryl sulphoxides and found that the substituent effect does not correlate with the Hammett o values but approximately with the a values. The pKa values thus obtained are summarized in Table 19. 

Our particular interest lies in the calculation of the linear energy deposition, or stopping power, of swift ions in materials, 5o(v). In the first Born approximation, and for a fully stripped projectile, this quantity can be written [2-4]... 

Eh Linear energy functional based on the Hamiltonian H it acts on the space of A-particle Trace Class operators. 

Et Linear energy functional based on the Kinetic Energy operator. 

The rates of radical-forming thermal decomposition of four families of free radical initiators can be predicted from a sum of transition state and reactant state effects. The four families of initiators are trarw-symmetric bisalkyl diazenes,trans-phenyl, alkyl diazenes, peresters and hydrocarbons (carbon-carbon bond homolysis). Transition state effects are calculated by the HMD pi- delocalization energies of the alkyl radicals formed in the reactions. Reactant state effects are estimated from standard steric parameters. For each family of initiators, linear energy relationships have been created for calculating the rates at which members of the family decompose at given temperatures. These numerical relationships should be useful for predicting rates of decomposition for potential new initiators for the free radical polymerization of vinyl monomers under extraordinary conditions. 

After complete formation of each successive monolayer of atoms, the next layer should start to form. This requires two-dimensional nucleation by the union of several adatoms in a position 1. Like three-dimensional nucleation, two-dimensional nucleation requires some excess energy (i.e., elevated electrode polarization). Introducing the concept of excess linear energy p of the one-dimensional face (of length L) of the nucleus, we can derive an expression for the work of formation of such a nucleus (analogous to that used in Section 14.2.2). When the step of two-dimensional nucleation is rate determining, the polarization equation becomes, instead of (14.39),... 

Linear Energy Transfer (LET)—A measure of the energy that a charged particle transfers to a material per unit path length. 

Quality Factor (Q)—The linear-energy-transfer-dependent factor by which absorbed doses are multiplied to obtain (for radiation protection purposes) a quantity that expresses - on a common scale for all ionizing radiation - the approximate biological effectiveness of the absorbed dose. 

Linear energy transfer (LET) kiloelectron volts per micrometer (keV pm"1) 1.602xl0"10 Jm"1 kiloelectron volts per micrometer (keV im ) 1.602x1 O 10 Jm 1... 

The range in tissues and linear energy transfer (LET) depend on the type of radiation emitted and its energy. The potent lethality of Auger and low-energy conversion electrons is demonstrated by intranuclear localization of the radioisotope due to their short ranges (about one cell nucleus in diameter). Alpha particles have ranges of several cell diameters (40-90 pm) and are effective in... 

Stopping power or linear energy transfer (LET) is the energy lost per unit path length. Equation 6-2 expresses this relationship. 

S = stopping power LET = linear energy transfer AE = energy lost AX = path length of travel... 

Linear energy transfer (LET) A function of the capacity of the radiation to produce ionization. LET is the rate at which charged particles transfer their energies to the atoms in a medium and a function of the energy and velocity of the charged particle. See Radiation dose. 

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