Dynamic Light Scattering and Its Application to Control Nanoparticle Aggregation in Colloidal Systems: A Review.

Colloidal systems and their control play an essential role in daily human activities, but several drawbacks lead to an avoidance of their extensive application in some more productive areas. Some roadblocks are a lack of knowledge regarding how to influence and address colloidal forces, as well as a lack of practical devices to understand these systems. This review focuses on applying dynamic light scattering (DLS) as a powerful tool for monitoring and characterizing nanoparticle aggregation dynamics.

Environmental assessment in fine jewelry in the U.S.-Mexico's Paso del Norte region: A qualitative study via X-ray fluorescence spectroscopy.

Heavy metal contamination in raw materials has spread widely in the United States. The high increased number of recalls in consumer products and the lack of stricter regulations in the raw materials to be used in the jewelry industry have raised concerns among consumers. Studies in low-cost jewelry have shown the presence and high content of heavy metals; this environmental problem led to a child's death after swallowing a charm containing elevated levels of lead (Pb).

Prediction of partial molar volumes of amino acids and small peptides: counting atoms versus topological indices.

Experimental data of partial molar volumes of amino acids and small peptides were compiled from several publications and enabled us to perform a predicative analysis based on quantitative structure-property relationships (QSPR). Based on the simplest level of the descriptors, the new method has high accuracy and was found to be more reliable when compared to the latter QSPR method based on topological indexes. Incorporation of isoelectric pH and 3-D solvent-accessible surface area parameters increased the predictability of the equation to a small extent.