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We have studied temporal variation in the sensitivity of phytoplankton photosynthesis to inhibition by ultraviolet radiation (UV; 280-400 nm) using biological weighting functions (BWFs) that quantify ...
The labile chlorophyll a (Chl a1 ) degradation product, 132 ,17 3 -cyclopheophorbide a enol (CPP516), was only recently found in marine sediments, where it can contribute a significant fraction to sol...
X-ray absorption measurements on Kr dissolved homogeneously in vitreous silica (1.97 wt% Kr) have been carried out at the Kr K-edge at 4.5 K, representing the first direct determination of the sites ...
Abstract: Formation of authigenic trioctahedral Mg-rich smectite is common in evaporative lake sediments, but was not described previously in modern marine evaporative environments. This study documen...
Surface colonization and microbial dissolution of pyrite were studied in the laboratory and by in situ surface colonization experiments conducted at Iron Mountain, California.Laboratory experiments in...
The relationship between loss of seed viability and the accumulation of chromosomal aberrations was investigated in both landraces and cultivars of the pea ( Pisum sativum L.). It was shown here, for ...
The effect of water (5 H2O 1 OH) on the environment of Co21and Ni21 in albite glass was investigated by electronic absorption spectroscopy. The visible spectra of Co21-doped glasses change only slight...
The hydrolytic behavior of Fe solutions at room temperature under acidic conditions was investigated. In the presence of Al ions, with Cl and NO3 as associated anions, the Fe hydrolysis began almost i...
Weathering of spodumene in a lateritized pegmatite in Western Australia was studied by investigating in situ samples by electron-beam techniques. The spodumene had mostly altered to smectite. However,...
Solutions containing AlCl3 and Si(OH)4 (concentrations ≤ 1.5 mM with molar Si:Al ratios of 1:2, 1:1 and 3:1) and FeCl2 (0, 0.5 and 1.0 mM) were adjusted to pH 8 with Ca(OH)2, and incubated at 23°C and...
Fifteen iron oxide accumulations from the bottoms of two Finnish lakes (搇ake ores? were found to contain as much as 50% Fe. Differential X-ray powder diffraction and selective dissolution by oxalate s...
Vermiculite, mixed-layer vermiculite-phlogopite, and smectite are presently forming from igneous and metamorphic bedrock in the alpine zone of the northern Cascades, Washington. In addition, south-fac...

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