Molar absorptivity

In this work, SrFe12O19 samples were synthesized by hydrothermal method. We systematically studied the influence of an alkaline environment (NaOH) with the molar ratio (R) of 2 , 3 and 4 on the structure, magnetic properties of SrFe12O19 particles prepared by hydrothermal method. The relation between morphology, magnetic properties and microwave absorption properties of materials have been investigated.

8p viambani 18-06-2024 2 1   Download

The synthesis, photophysical and electrochemical properties of hexyl thiophene substituted thieno[b]-fused BODIPY structure are reported within this work. One such derivative, HTFBod, has been studied, which is one of the rare compounds that has a maximum absorbance wavelength greater than 750 nm among fused BODIPY compounds. In addition, it preserves its significant spectral properties such as high molar absorptivity and fluorescence quantum yield.

17p lyhuyenthu 31-01-2023 4 2   Download

An accurate, precise, and simple spectrophotometric method is proposed for the determination of the antithyroid drug carbimazole using ruthenium(III) chloride. This method is based on the formation at room temperature of a stable yellow-colored complex with λmax 370 nm. The method has a Beer’s law range of 7.81 to 1.95 × 10 2 µg mL−1, molar absorptivity coefficient ε = 1.519 × 103 L mol−1 cm−1, and correlation coefficient of 0.997. The metal:ligand (M:L) ratio of the complex was confirmed by the mole ratio and Job’s method of continuous variation, suggesting a 1:2 stoichiometry.

18p tudichquannguyet 29-11-2021 8 0   Download

In this paper, a fast, cheap, simple, sensitive and selective spectrophotometric method based on high spin peroxo-Fe(III)-EDTA complex in the alkaline medium was developed for the determination of hydrogen peroxide (H2O2) in real water samples. The purple-coloured complex with a maximum absorbance at a wavelength of 525 nm was formed. Various parameters such as type of stabilizer reagent and its concentration, reaction time, Fe(III), EDTA and NH3 concentration were optimized. The method was confirmed with the Beer’s law with a molar absorption coefficient of 267.36 L mol−1cm −1 in the 8.

13p tudichquannguyet 29-11-2021 13 2   Download

The authors of the article suggest simple and express method of spectrophotometric determination of iron (III) through derivatives of monoammonium salt of glycyrrhizic acid (MASGA). The spectral characteristics of the MASGA-Fe (III) complex - absorption maxima (λmax = 440nm) and the actual molar extinction coefficient (ε = 3,425 × 102) were determined. The optimal conditions for the determination of iron (III) in the range of its concentrations of 2,0–45,0 μg / 25 ml of solution have been established.

7p trinhthamhodang11 27-04-2021 19 1   Download

Ligand exchange method is introduced as an alternative to Job’s and mole ratio methods for studying the stoichiometry of relatively weak metal complexes in solutions. The method involves adding varying amounts of a ligand (L) to an excess constant amount of a colored complex (MX) with appropriate stability and molar absorptivity.

7p vijiraiya2711 27-05-2020 7 1   Download

The mineral component of kaolin clay in Tung Ba commune analyzed by X-ray diffraction is composed mainly of kaolinite (24–27%), illite (26–30%) and quartz (40–44%). Chemical composition (wt%) of Tung Ba kaolin determined by X-ray fluorescence (XRF) shows SiO2 at 59.92–64.98, Al2O3: 18.95–20.82, Fe2O3: 2.28–3.95, SO3: 2.47–4.66, CaO: 0.12–0.36, MgO: 1.72–2.13 and TiO2 at 0.75–1,08. To fabricate geopolymer ceramic, kaolin clay was transformed into metakaolin with the optimal parameters of calcination: the temperature at 750°C and heating time of 120 min.

15p 12120609 22-03-2020 14 1   Download

A simple and sensitive extraction-spectrophotometric method is described for the determination of sulfonamide drugs, namely sulphamethoxazole, sulphaguanidine, sulphaquinoxaline, sulphametrole and sulphadimidine, in both pure form and in the dosage forms available in Egyptian markets. The method is based on ion-pair formation between the sulphonamides and Mo(V)-thiocyanate inorganic complex in a sulphuric acid medium followed by extraction of the coloured ion-pairs with 1,2-dichloroethane. The optimum conditions are established.

6p kethamoi1 20-11-2019 14 1   Download

The effect of optimum conditions via pH, dye concentration, time and solvent are studied. Beer’s law is obeyed in the concentration ranges 0.50-25.0 μg/mL with molar absorptivity of 1.46 104 , 1.83 104 and 2.07 104 L. mol-1 . cm-1 and limit of detection (LOD) of 0.105, 0.101, 0.084 for BPB, BCG and BTB methods, respectively. No interference was observed from common excipients present in pharmaceutical formulations. The proposed method has been applied successfully to determine ciprofloxacin in pharmaceutical preparation (tablets, infusion and eye drops).

8p bautroibinhyen211 27-11-2018 23 1   Download

The molar absorptivities were 1.5.104 l.mol-1 .cm-1 and Sandell's sensitivity index of 0.0263 μg.cm-2 . Recoveries of mesalazine from excipients were 95.4 -102.3 %. No interference was observed from common excipients present in pharmaceutical formulations. The proposed method has been applied successfully to determine mesalazine in pharmaceutical preparation as tablets (Pentasa and Sunmesacol).

6p lamtan3547 04-11-2018 56 2   Download

The putative gene ofPlasmodium vivaxserine hydroxymethyltransferase (PvSHMT; EC 2.1.2.1) was cloned and expressed in Escherichia coli. The purified enzyme was shown to be a dimeric protein with a monomeric molecular mass of 49 kDa. PvSHMT has a maximum absorption peak at 422 nm with a molar absorption coefficient of 6370m )1 Æcm )1 . The Kd for binding of the enzyme and pyridoxal-5-phosphate was 0.14 ± 0.01lm.

14p vinaphone15 25-02-2013 48 2   Download