2. The nunmber of reactive SH groups/molecule in the haemoglobins studied approximate either to 2 or to 4. 3. The behaviour of the reactive SH groups differs from that of cysteine in three ways: (a) the rate of reaction of heavy-metal ions with the reactive SH groups is slower than with cysteine; (b) thiosulphate interferes with the reaction between Ag+ ions and the reactive SH groups of human ...

objective: garlic is a plant has been used as a flavor, and anti-microbial and anti-diarrheal agent. infectious bronchitis virus (ibv) is a coronavirus. the available vaccines against ibv cannot cover new variants. this study evaluated the inhibitory effects of garlic extract on ibv.  materials and methods: the constituents of garlic extract were detected by gas chromatography. this study was d...

Protonation of gossypol Schiff bases (S1 and S2), possessing different numbers of basic N-atoms, was studied using potentiometric, spectroscopic, ESI MS and PM5 methods. Titration of S1 and S2 with HClO(4), monitored by the FT-IR and (1)H NMR, indicated that the change from the enamine-enamine into the protonated imine-imine tautomeric form occurs at different Schiff base-H(+) ratio. The FT-IR ...

An automatic system for acid-base titrations by electrogeneration of H(+) and OH(-) ions, with potentiometric end-point detection, was developed. The system includes a PC-compatible computer for instrumental control, data acquisition and processing, which allows up to 13 samples to be analysed sequentially with no human intervention.The system performance was tested on the titration of standard...

This is an easy and inexpensive laboratory experiment in which undergraduate students at the Bachelor’s degree level Chemistry can measure formation constants of complexes [Ni(en)n(OH2)6–2n]2+ (n = 1, 2 or 3; en ethylenediamine) through acid–base titration. The background information necessary to understand activity involves familiarity with equilibria basic coordination chemistry, lab experien...

BACKGROUND AND AIMS Manual laboratory continuous positive airway pressure (CPAP) titration for obstructive sleep apnoea (OSA) is costly, time intensive and delays access to treatment. Automatic positive airway pressure (APAP) titration has the potential to reduce cost and improve access to treatment. The aim of this study was to assess the clinical efficacy and costs of APAP titration compared ...

As a mono-sodium salt form of alendronic acid, alendronate sodium presents multi-level ionization for the dissociation of its four hydroxyl groups. The dissociation constants of alendronate sodium were determined in this work by studying the piecewise linear relationship between volume of titrant and pH value based on acid-base potentiometric titration reaction. The distribution curves of alend...

the formation constants and gibbs free energy for the interaction of rnsnclm (n = m = 2, r = me, ph, n-bu or n = 4, m = 0, r = ph) compounds as acceptors, with ml complexes (h2l = n,n'-bis(salicylidene)-2-aminobenzylamine (salabza-h2) and its derivatives, m = mn2+ or zn2+), as donors in n,n'-dimethylformamide (dmf) as solvent were studied. these parameters were measured by using uv-vis spectrop...