The experimental degradation of a water soluble dye, potassium indigo tetrasulfonate salt, has been studied using stand-alone ozonation and photocatalytic oxidation process. Progress of the dye oxidation was followed by UV-VIS spectrophotometric measurements at controlled operating conditions. The organic content of reaction samples was measured to verify the process efficiency in dye mineraliz...

We review how major cell behaviors, such as bacterial growth laws, are derived from the physical chemistry of the cell's proteins. On one hand, cell actions depend on the individual biological functionalities of their many genes and proteins. On the other hand, the common physics among proteins can be as important as the unique biology that distinguishes them. For example, bacterial growth rate...

This review focuses on MR contrast agents that are responsive to a change in physiological environment. The "response" mechanisms are dependent on 6 physicochemical phenomena, including the accessibility of water to the agent, rotational tumbling time, proton exchange rate, electron spin state, MR frequency, or local field inhomogenieties caused by the agent. These phenomena can be affected by ...

Abstract This paper presents the nonlinear dynamic analysis of an ideal two-reactant-two product reactive distillation. The impact of disturbance magnitudes and directions on openloop stability of the system is studied. An analysis of the physicochemical phenomena present in reactive distillation processes that, under certain operational conditions, causes special types of nonlinear behavior is...

Ion pairs (also known as salt bridges) of electrostatically interacting cationic and anionic moieties are important for proteins and nucleic acids to perform their function. Although numerous three-dimensional structures show ion pairs at functionally important sites of biological macromolecules and their complexes, the physicochemical properties of the ion pairs are not well understood. Crysta...

Modification to find the best physicochemical properties of minocycline hydrochloride ointment for optimum treatment of bedsore was investigated by coformulating various types of cyclodextrins (CyD) in the ointment base. It was found that the drug release rate from the ointment base was modified according to the preparation method of ointment base and the type of CyD admixed. The physicochemica...

Problem statement: Since the earliest publication on the technique, Reversed-Flow Gas Chromatography (RF-GC) has been used to determine physicochemical properties by measuring the value of one in the presence of another. The method is precise, accurate and simple compared to other conventional techniques. Approach: The experimental setup consists of a small modification of a commercial gas chro...

We have developed a modular pair of laboratory experiments for use both in undergraduate physical chemistry and biochemistry. Both laboratories examine the thermodynamics of the binding of a small molecule, eosin, to the protein lysozyme. The assay for binding is the quenching of lysozyme fluorescence by eosin through resonant energy transfer. In both experiments students measure fluorescence q...

Physical chemistry describes systems in terms of their energy and their boundary conditions. Quantitative knowledge of the future state of a system can be derived from a set of differential equations, relating to the functions defining that system, that provide reasonable estimates of its behavior. This approach, howe v e r, implies first the need to leave aside the individual characteristics o...

There is a widespread agreement that more effective drug delivery vehicles with more alternatives, as well as better active pharmaceutical ingredients (APIs), must be developed to improve the efficacy of microbicide products. For instance, in tropical regions, films are more appropriate than gels due to better stability of drugs at extremes of moisture and temperature. Here, we apply fundamenta...