We have performed molecular dynamics simulations of liquid water at 298 and 258 K to investigate the effects of hydrogen-bond environment on various single-particle and pair dynamical properties of water molecules at ambient and supercooled conditions. The water molecules are modelled by the extended simple point charge (SPC/E) model. We first calculate the distribution of hydrogen-bond environ...

The purpose was to determine volatile fa t ty acid concentrations at normal (18 C) and high (35 C) ambient temperature, and to determine the effect of increasing the rumen temperature with an intraruminal heating coil in an 18 C ambient temperature. Four nonlactating, fistulated Holstein cows were placed in a climatically controlled chamber. Treatments were (18) ambient temperature ]8.2 C; (35)...

We determine the molecular structure and orientation at the liquid-vapour interface of water using an electronically coarse grained model constructed to include all long-range electronic responses within Gaussian statistics. The model, fit to the properties of the isolated monomer and dimer, is sufficiently responsive to generate the temperature dependence of the surface tension from ambient co...

The structure and properties of supercritical water is investigated in relation to the energy and environmental issues of the 21 century. Molecular interpretations are given to the temperature dependence of the hydrogen-bonding structure, dynamics, and chemical reactions of supercritical water. The three-dimensional network structure, characteristic of ambient water, is broken down in hot expan...

Responses to elevated CO"2 have not been measured for natural grassland ecosystems. Global carbon budgets will likely be affected by changes in biomass production and allocation in the major terrestrial ecosystems. Whether ecosystems sequester or release excess carbon to the atmosphere will partly determine the extent and rate that atmospheric CO"2 concentration rises. Elevated CO"2 also may ch...

Copper concentrations in parts of San Diego Bay (CA, USA) exceed ambient water quality criteria (WQC; currently 3.1 microg/L dissolved, U.S. Environmental Protection Agency [U.S. EPA]). In order to better understand the bioavailability of copper to water-column organisms in the bay, toxicity tests were performed with copper added to surface water collected from various sites in the estuary over...