introduction: scatter radiation is one of the major sources of error in nuclear medicine data processing. different methods of scatter correction have been introduced in order to improve the quality of data. however the best method is to avoid recording of scatter photons in acquisition. the only difference between scattered and non-scattered photons is the energy. pulse height analyzer is the ...

The tautomeric and recognition properties of thymine, 2and 4-thiothymines have been studied by means of accurate ab initio methods combined with molecular dynamics simulations and free energy calculations. In contrast to previous suggestions in the literature, the replacement of carbonyl oxygens by sulphur atoms does not lead to dramatic changes in tautomeric properties of the pyrimidine deriva...

Total and partial charge transfer cross sections are calculated in collisions of protons with the nitrogen molecule at energies between 0.1 and 10 keV. Ab initio potential energy curves and nonadiabatic couplings have been obtained for a number of N2 bond lengths using a multireference configuration interaction method. The influence of the anisotropy of the target molecule is investigated. Resu...

A method is described for embedding a deformable, elastic, membrane within a lattice Boltzmann fluid. The membrane is represented by a set of massless points which advect with the fluid and which impose forces on the fluid which are derived from a free energy functional with a value which is dependent upon the geometric properties of the membrane. The method is validated in two dimensions with ...

Hydrogen binding energies are calculated for the different isomers of 1:1 complexes of methanol, ethanol and water using ab initio methods from MP2 to CCSD(T). Zero-point energy vibration and counterpoise corrections are considered and electron correlation effects are analyzed. In methanol–water and ethanol–water the most stable heterodimer is the one where the water plays the role of proton do...

An accurate line list, VOMYT, of spectroscopic transitions is presented for hot VO. The 13 lowest electronic states are considered. Curves and couplings are based on initial ab initio electronic structure calculations and then tuned using available experimental data. Dipole moment curves, used to obtain transition intensities, are computed using high levels of theory (e.g. MRCI/aug-cc-pVQZ usin...

A pond heat and temperature regulation (PHATR) model was designed to: (1) predict the temperature for earthen outdoor aquaculture ponds and (2) determine the size of energy transfer mechanisms affecting energy gains or losses for these ponds. The model solves a first order, no-linear differential equation using a 4th order Runge-Kutta numerical method and various input data (weather data, pond ...