In the study, multivariate statistical methods including factor, principal component and cluster analysis were applied to analyze surface water quality data sets obtained from Xiangjiang watershed, and generated during 7 years (1994-2000) monitoring of 12 parameters at 34 different profiles. Hierarchical cluster analysis grouped 34 sampling sites into three clusters, including relatively less p...

We performed a series of molecular dynamics (MD) simulations on Nafion membranes which contain various quantities of water and methanol. The simulations gave a variety of nanoscale phase separated structures, such as cluster structures, channel structures, and cluster-channel structures. This is the first work that an atomistic MD simulation reproduced such nanoscale phase separations from rand...

Water clusters of protonated substituted anilines generated by an electrospray ion source have been investigated using a Fourier Transform ion cyclotron resonance mass spectrometer. It is observed that evaporation kinetics and cluster distributions are highly dependent on sites of protonation in the substituted anilines. Based on the examination of the water cluster distributions of protonated ...

The hydrogen bond interaction between acetone and water is investigated at the ab initio MBPT/CC levels using different approximations and basis sets. At the highest level the binding energy is obtained as 5.6 kcal mol. Analysis of the electron correlation effects shows only a very mild influence on the binding energy. Study of the blue shift of the n! p transition of acetone in water shows tha...

Understanding the properties of hydrated electrons, which were first observed using pulse radiolysis of water in 1962, is crucial because they are key species in many radiation chemistry processes. Although time-resolved spectroscopic studies and molecular simulations have shown that an electron in water (prepared, for example, by water photoionization) relaxes quickly to a localized, cavity-li...

Here we report ion mobility experiments and theoretical studies aimed at elucidating the identity of the acetylene dimer cation and its hydrated structures. The mobility measurement indicates the presence of more than one isomer for the C(4)H(4)(●+) ion in the cluster beam. The measured average collision cross section of the C(4)H(4)(●+) isomers in helium (38.9 ± 1 Å(2)) is consistent with the ...

Water dissociation on copper is one of the rate-limiting steps in the water-gas-shift (WGS) reaction. Copper atoms dispersed evenly from freshly made catalyst segregate to form clusters under the WGS operating conditions. Using density functional theory, we have examined water adsorption and dissociation on the smallest stable 3-dimensional copper cluster, Cu(7). Water molecules are adsorbed on...

Let us briefly mention the various molecular species that were used above in order. The basic component in the system is the solvent, which should represent water. Water is a strongly associating liquid. To mimic clusters of water molecules we adopt an extremely simplistic model for which water molecules are seen as a cluster of five monomers. More specifically we have one central segment surro...