This paper presents the results of a two-year field campaign to determine the spatial and temporal variability of groundwater interaction with surface waters in two Cretaceous Chalk catchments (the Pang and Lambourn) in the Upper Thames in Berkshire, UK, based on measurement of dissolved carbon dioxide (CO 2). Average stream water concentrations of dissolved CO 2 were up to 35 times the concent...

In this article, the sorption process of Cr, As and V as oxoanions using modified mordenite zeolite as sorbent has been experimentally estimated. The sample of mordenite zeolite was synthesized and modified and batch method was employed for analysis. Parameters such as sorbent dose, concentration of metal oxoanions in solution ranging from 50 to 5 μg/l and effect of contact time were studied. E...

The capacity of various ATPase preparations from beef heart mitochondria to catalyze exchange of phosphate oxygens with water has been evaluated. Oligomycin-sensitive ATPase preparations retain a capacity for considerable intermediate Pi equilibrium HOH exchange per Pi formed during ATP hydrolysis at relatively high ATP concentration (5 mM). Submitochondrial particles prepared by an ammonia-Sep...

Stoichiometric titrations of human hemoglobin with carbon monoxide show that the interaction of hemoglobin with ligand is accompanied by proportional changes in both the Soret and visible absorption bands. This linearity has been observed in neutral solutions, both in the presence and absence of 2 M NaCl, and in alkaline solutions at pH 9.2. It is concluded that the liganded intermediates takin...

background and purpose: phenol and derivatives are common pollutants of drinking water which are blamed for crucial adverse effects such as poisoning, cancer, and malformation. in this study, an activated carbon of miswak’s root (mr) was used for the removal of phenol from aqueous solutions as a low-cost and high surface adsorbent. materials and methods: adsorption experiments were then conduct...

background and purpose: the 2-chlorophenol (2-cp) and 4-chlorophenol (4-cp) are phenolic compounds which may have adverse effects on human and environment. therefore, removing these compounds from water and wastewater is necessary. this study aims to analyze 2-cp and 4-cp removal by using azolla filiculoides biomass. materials & methods: azolla biomass was sun dried, crushed and sieved to parti...

We have studied theoretically the partition equilibrium of a cationic drug between an electrolyte solution and a membrane with pH-dependent fixed charges using an extended Donnan formalism. The aqueous solution within the fixed charge membrane is assumed to be in equilibrium with an external aqueous solution containing six ionic species: the cationic drug (DH(+)), the salt cations (Na(+) and Ca...

[1] Secondary organic aerosol (SOA) formed from partitioning of oxidation products of anthropogenic and biogenic volatile organic compounds (VOCs) accounts for a substantial portion of atmospheric particulate matter. In describing SOA formation, it is generally assumed that VOC oxidation products rapidly adopt gas-aerosol equilibrium. Here we estimate the equilibration timescale, teq, of SOA ga...

The pinning effect is useful for restraining austenite grain growth in low alloy steel and improving heat affected zone toughness in welded joints. We propose a new calculation model for predicting austenite grain growth behavior. The model is mainly comprised of two theories: the solute-drag effect and the pinning effect of TiN precipitates. The calculation of the solute-drag effect is based o...

Nerve growth factor (NGF) is a protein composed of two identical chains of mass 13,259. An analysis of the sedimentation equilibrium, sedimentation velocity, and gel filtration behavior of dilute solutions of NGF indicates the existence of a rapidly reversible monomer in equilibrium dimer equilibrium and that the association constant K for the reaction at neutral pH is 9.4 X 10(6)M-1. Reaction ...