A transient intermediate of cytochrome c oxidase has been generated by exposing the enzyme to a laser beam in the presence of oxygen. This intermediate develops when the enzyme is simultaneously reduced photoreductively and oxidized chemically, thereby forcing it to turn over. Under these conditions a form of the enzyme is generated with a line at 477 cm-1 in the resonance Raman spectrum, which...

Cyanobacterial blooms result in high level of cyanobacterial extracellular polymeric substances (EPS) in water. The effects of bloom-forming cyanobacterial EPS on the distribution of Cd(II) in the interface between sediment and water is unknown. Clay is a main component in sediment. The effects of EPS, originated from a typical bloom-forming cyanobacterium Microcystis aeruginosa, on the adsorpt...

The anomeric methyl D-glucopyranosides were treated with NJV-diethylaziridinium chloride in various molarities of aqueous sodium hydroxide at variable ionic strength and constant ionic strength. It was found that the extent of reaction of the hydroxyl groups at C-2, C-3, and C-4 decreased with increasing concentration of base. Reaction at the C-6 hydroxyl group remained essentially constant wit...

The fiterature of soil bacteriology is replete with assertions to the effect that soil bactena of value for the maintenance of an appropriate soil condition need an alkaline medium for their proper development. This has been repeatedly emphasized, particularly in connection with the nitrifying and the nltrogen-fixing flora of the soil. Actual evidence substantiating such assertions has never be...

Hydroxyl radicals (OH) are a key species in atmospheric photochemistry. In the lower atmosphere, up to ~30% of the primary OH radical production is attributed to the photolysis of nitrous acid (HONO), and field observations suggest a large missing source of HONO. We show that soil nitrite can release HONO and explain the reported strength and diurnal variation of the missing source. Fertilized ...

Eun-Jung Shin, Yeong-Joon Park, Bin-Na Lee, Ji-Hyun Jang, Hoon-Sang Chang, In-Nam Hwang, Won-Mann Oh, Yun-Chan Hwang* Chonnam National University School of dentistry, Department of Dental Materials, Chonnam National University School of Dentistry and Dental Science Research Institute, Department of Conservative Dentistry, Chonnam National University School of Dentistry and Dental Science Resear...

A benchmark study has been carried out on the ground-state potential curve of the hydroxyl anion, OH-, including detailed calibration of both the l-particle and n-particle basis sets. The CCSD(T) basis set limit overestimates omega(e) by about 10 cm(-1), which is only remedied by inclusion of connected quadruple excitations in the coupled cluster expansion--or, equivalently, the inclusion of th...

The structural saturation and stability, the energy gap, and the density of states of a series of small, siliconbased clusters have been studied by means of the PM3 and some ab initio ~HF/6-31G* and 6-31111G**, CIS/6-31G* and MP2/6-31G*! calculations. It is shown that in order to maintain a stable nanometric and tetrahedral silicon crystallite and remove the gap states, the saturation atom or s...

We have studied the hydration and diffusion of the hydroxyl radical OH0 in water using classical molecular dynamics. We report the atomic radial distribution functions, hydrogen-bond distributions, angular distribution functions, and lifetimes of the hydration structures. The most frequent hydration structure in the OH0 has one water molecule bound to the OH0 oxygen (57% of the time), and one w...

The structures, stabilities, thermodynamic quantities, dissociation energies, infrared spectra, and electronic properties of LiOH hydrated by up to seven water molecules are investigated by using the density-functional theory and the Møller-Plesset second-order perturbation theory (MP2). Further accurate analysis based on the coupled-cluster theory with singles, doubles, and perturbative triple...