The fate of chemical pollutants in the environment is determined by various factors including type and strength their interactions with reactive surfaces soils sediments. In present work hexachlorobenzene (HCB) surface a common clay mineral belonging to smectite group montmorillonite (MNT) studied means density functional theory method. MNT net charge, induced isomorphic substitutions, systemat...

A nearly monomineralic 1.5 m thick bentonite bed sampled in Melo (Uruguay) appears to be a pure high-charge montmorillonite: [Si3.94 Al0.06] (Al1.40 Fe0.11 Ti0.02 Mg0.49 Mn0.01) O10 (OH)2 Na0.01 K0.08 Ca0.18. However, contrasting swelling behaviors have been evidenced by fitting the experimental X-ray diffraction patterns recorded on oriented preparations of the same sample in different saturat...

It is well known that unitary symmetries can be “gauged,” i.e., defined to act in a local way, which leads to a corresponding gauge field. Gauging, for example, the charge-conservation symmetry leads to electromagnetic gauge fields. It is an open question whether an analogous process is possible for time reversal which is an antiunitary symmetry. Here, we discuss a route to gauging time-reversa...

The aspartate chemoreceptor Tar has a thermosensing function that is modulated by covalent modification of its four methylation sites (Gln295, Glu302, Gln309, and Glu491). Without posttranslational deamidation, Tar has no thermosensing ability. When Gln295 and Gln309 are deamidated to Glu, the unmethylated and heavily methylated forms function as warm and cold sensors, respectively. In this stu...

The edit distance between given two strings X and Y is the minimum number of edit operations that transform X into Y without performing multiple operations in the same position. Ordinarily, string editing is based on character insert, delete, and substitute operations. Motivated from the facts that substring reversals are observed in genomic sequences, and it is not always possible to transform...