جستجوی مقالات مرتبط با کلیدواژه "metal ions" در نشریات گروه "ریاضی"

Metal ions are naturally occurring inorganic substances required in humans in a certain amount by mg/day. They are essential components of biological structures and have an important effect on and play a key role in a variety of the process necessary for life throughout mediating vital biochemical reactions. The role of essential nutrient metal ions as (Na+, K+, Ca2+, and Mg2+) often deficient in our food stuffs, its vitally essential in the function of the human body. Excessive levels, a level higher than needed for biological functions, of these elements can be toxic for the body health. Therefore, it has been found that the imbalances in the optimum levels of trace elements may adversely affect biological processes and are associated with many fatal diseases..In the recent study, 15 samples from deferent patients in ages (18-45) and deferent living environments have been taken from Hawari hospital Kidney division, Benghazi, Libya. The samples were treated by separation of serum from the blood without any chemical treatment. The studied values were measured by spectrophotometer as element analysis. The studied values for metal ions (Na+, K+, Ca2+, and Mg2+) in serum samples, clearly reflect the lack of healthy food taken by the patients, which have caused some decrease in the normal values, even though still under control. The results showed a satisfactory values comparing with the normal values confirmed by WHO.

In this study, the complexation reaction between Alprazolam (ALP) and metal ions (Zn2+, Ni2+, Cu2+ and Co2+) was investigated by using spectrophotometry in ethanol solvent. The stoichiometry of M+/ALP complexes was calculated by applying the Job, molar ratio and Continuous Changes methods and the relevant diagrams were plotted for each metal ions in each method. The results show that the obtained complexes are 1:3. In the Continuous Changes method a defeat was observed at molar fraction of 0.66 for all complexes, which confirms complexes with 1:3 mole ratio. The formation constants of complexes were determined by using nonlinear least square method (KINFIT software) and it was concluded that the stability of complexes is varied in the order Cu2+> Co2+> Ni2+ > Zn2+. Therefore, Cu is the strongest and Zn formed with Alprazolam ligand is the weakest complex.

A method for the simultaneous spectrophotometric determination of nickel, cobalt and copper based on the formation of their complexes with 2-(2-Thiazolylazo)-p-Cresol (TAC) in micellar media of Triton X-100 is proposed. The absorbance spectra were recorded in the range of 500 to 800 nm. The linear concentration range for nickel, cobalt and copper in solution calibration sets were 0.05–1.80, 0.10–6.41 and 0.10–6.54 μg/ml, respectively. The effects of experimental parameters such as pH, time, concentration of ligand and surfactant on the sensitivity of method were investigated. The data obtained from the experiments were processed by the partial least squares (PLS), orthogonal signal correction-partial least squares (OSC-PLS) and principle component-back propagation artificial neural network (PC-BPANN). A set of synthetic mixtures of nickel, cobalt and copper was evaluated and the results obtained by each chemometric approaches were compared with different testing methods. The OSC-PLS method was selected because afforded better results than the others. The method was satisfactorily applied for determination of nickel, cobalt and copper in alloy samples. The accuracy was determined using comparing the results to the reference values and also independent analysis by flame atomic absorption spectrometry.