The alkaline hydrolysis of two aromatic esters, 2-naphthyl acetate (2NA) and phenyl acetate (PhA) has been tackled in this work. The reaction has been followed in water and in the presence of cationic surfactants with different chain lengths: dodecyltrimethylammonium bromide (DTABr), tetradecyltrimethylammonium bromide (TTABr), and hexadecyltrimethylammonium bromide (CTABr) and the correspondin...

Molecular dynamics (MD) simulations are used to probe the origin of the unexpected temperature dependence of salt accumulation in the C-terminal region of the protein human lymphotactin. As in previous MD simulations, sodium ions accumulate in an enhanced manner near the C-terminal helix at the lower temperature, while the temperature dependence of chloride accumulation is much weaker and sligh...

This research has demonstrated that simple structural and potential models can qualitatively and quantitatively predict properties in dense hydrothermal solutions of sodium chloride and water using molecular dynamics simulation. The PTFxi behavior of simulated model systems at 250 bar and 21 wt % NaCl compared favorably to experimental data from ambient to near-critical temperatures as represen...

The cationic detergent tetradecyltrimethylammonium ion interacts with four binding sites on the surface of AI polypeptide from human serum high density lipoprotein and 10 sites on the AI1 polypeptide with association constants of 2 X lo4 and 1 x lo4 liters per mole, respectively. The sites on AI appear to be primarily hydrophobic in that the anionic detergent sodium dodecyl sulfate binds to the...

Complexation in symmetric solutions of oppositely charged polyelectrolytes is studied theoretically. We include polyion crosslinking due to formation of thermoreversible ionic pairs. The electrostatic free energy is calculated within the Random Phase Approximation taking into account the structure of thermoreversible polyion clusters. The degree of ion association is obtained self-consistently ...

Ion conductivity and the gating characteristics of tetrameric glutamate receptor ion channels are determined by their subunit composition. Competitive homo- and hetero-dimerization of their amino-terminal domains (ATDs) is a key step controlling assembly. Here we measured systematically the thermodynamic stabilities of homodimers and heterodimers of kainate and AMPA receptors using fluorescence...

Liquid ion association in ionic liquids (ILs) has been examined using a comprehensive series of electronic structure calculations that measure the relative extents of ion association and probe stabilisation for the photochromic dye nitrobenzospiropyran (BSP) in a range of ILs featuring both long-tailed phosphonium cations and short-tailed imidazolium cations, paired with both chloride and NTf(2...

A new, simple, rapid, and cheap method for determination of trace amounts of nitrite ion is reported.Determination is based on reduction of bromate ion by nitrite ion, in the presence of murexide inacidic media. During reaction of bromate ion with nitrite ion, the reaction mixture is decolorized.The absorbance changes is then monitored spectrophotometricaly at 520 nm, at 25 °C. Dynamicrange of ...

considering the importance of parasitic wasps in biological control of pests, a faunal study was conducted in the year 2012 on eulophid wasps (hym.: chalcidoidea) in rice fields in the east of guilan province, southern coast of caspian sea. several specimens were captured via malaise traps. the specimens were identified as aprostocetus deobensis (graham), aprostocetus mycerinus (walker), elasmu...

this study was conducted based on primary data collected using a questionnaire. a total of 90 respondents among farmers associations were interviewed in kano state of nigeria. therefore, double stage stratified and purposive simple random sampling technique was used to select 30 respondents in each of three (3) farmers associations, one from each of the three (3) agricultural zones of the state...