The acid-base equilibrium of lorazepam was studied by means of potentiometry andmultiwavelengths spectrophotometry. The stoichiometric equilibrium constants were determinedat 25 °C and constant ionic strength 0.1 mol L-1 (NaCl). The acidity constants pK1=1.58±0.05and pK2=11.67±0.07 were found by potentiometry, and pK1=1.54±0.02 and pK2=11.61±0.03 bymulti-wavelengths spectrophotometry. Potentiom...

In  this  paper a  non-linear  model  with  fractional  order  is  presented  for  analyzing  and  controlling the  spread  of  HIV virus.  Both  the  disease-free  equilibrium and the endemic equilibrium are  found  and  their  stability is  discussed. The basic reproduction number , which is a function of the constant parameters in the model, plays an essential  role in the stability of  the ...

using hartree–fock (hf) and ِِdensity functional theory (dft) calculations the thermodynamic properties such as thermal energy , , thermal enthalpy , , thermal entropy , , thermal gibbs free energy , , heat capacity ,cv, and molecular structures of several species involving in keto↔enol tautomerism related to acetaldehyde (a), 5,5-dimethyl-1,3-cyclohexanedione (dimedone) and  acetylacetone (aa) h...

the complexation of sodium molybdate with para-sulfonatocalix [4] arene was studied in thetemperature range from 20 to 40 °c and ph = 5.8 by spectroscopic method in water solution. thestability constants of complexes were calculated by the multiwavelength analysis of spectral datausing squad program. the equilibrium constant, spectroscopic data, molar absorptivities andconcentrations of all spe...