Records of Enriched Uranium Atmospheric Deposition in Pond Sediments in Piketon, OH

The enrichment of uranium, often for nuclear weapons programs and commercial nuclear reactors, produces higher concentrations of radioactive uranium 235 (235U) than what naturally occurs, which can pose a human health hazard. The most abundant naturally occurring uranium isotope is 238U, which is still radioactive, however a higher concentration of 235U skews the observed isotopic uranium distribution. The Department of Energy Portsmouth Gaseous Diffusion Plant, located near Piketon, OH, enriched uranium from 1954 to 2001 and 235U pollution has recently been detected in air and sediment samples in the surrounding community. The extent of the 235U contamination was tested using sediment core samples from ponds within the vicinity of the plant. Cores were processed in the laboratory by depth intervals to capture the history of atmospheric deposition of 235U. Analyzing the samples with an ICPMS instrument allowed for ratios between enriched 235U and naturally occurring 238U to be calculated, thus unearthing the level of contamination. These results will provide the citizens of Piketon, OH with scientific evidence to facilitate their understanding of the uranium contamination within their community

Declaración ambiental

EMAS, ISO 14001:2004Hote

Application of synchrotron radiation for measurement of iron red-ox speciation in atmospherically processed aerosols

In this study, ambient atmospheric particulate matter samples were collected using a size-resolved impactor sampler from three urban sites. The purpose of this study is to gain a better understanding of transformations of aerosol-bound iron as it is processed in the atmosphere. Thus, the aerosol samples were artificially aged to represent long-term transport (10 to 40 days) or short-term transport (1 to 10 days) and were measured for iron at several time points. At each time point, iron was measured in each size fraction using three different techniques; 1) inductively coupled plasma-mass spectrometry (ICPMS) for total iron, 2) x-ray absorbance near edge structure (XANES) spectroscopy for the measurement of total Fe(II) and Fe(III), and 3) a wet-chemical method to measure soluble Fe(II) and Fe(III). Prior to aging, the XANES spectroscopy results show that a majority (>60% for each size fraction) of the total iron in the PM is in the form of Fe(III). Fe(III) was shown to be a significant fraction of the soluble iron (sometimes >50%), but the relative significance of Fe(III) was found to vary depending on the site. Overall, the total soluble iron depended on the sampling site, but values ranged from less than 1% up to about 20% of the total iron. Over the course of the 40 day aging period, we found moderate changes in the relative Fe(II)/Fe(III) content. A slight increase was noted in the coarse (>2.5 µm) fraction and a slight decrease in the 0.25 to 0.5 µm fraction. The soluble fraction generally showed (excepting one day) a decrease of soluble Fe(II) prior to 10 days of aging, followed by a relatively constant concentration. In the short-term transport condition, we found that the sub-micron fraction of soluble Fe(II) spikes at 1 to 3 days of aging, then decreases to near the initial value at around 6 to 10 days. Very little change in soluble Fe(II) was observed in the super-micron fraction

The Syntheses and Characterization of Aza Coronands and Cryptands Containing the 2,6-Pyridino And/Or the 1,8-Naphthyridino Subunits.

The syntheses of coronands and cryptands containing the 2,6-pyridino and 1,8-naphthyridino subunits have been accomplished. These macrocycles may contain only nitrogen heteroatoms while others contain both nitrogen and oxygen heteroatoms. Transition metal complexes have been formed only with the macrocycles which contain strictly nitrogen heteroatoms; no complexes have been found for the macrocycles which contain oxygen and nitrogen atoms. A diprotonated cobalt(II) tetrachloride salt was formed from the dimeric macrocycle which results from the reaction of 2,6-dichloropyridine with N,N-bis-2-hydroxyethylpiperazine. Several analogous systems have also been synthesized. A hexaaza-18-crown-6 analogue has also been synthesized by the treatment of 2,6-bis(chloromethyl)-pyridine with N,N\u27-dimethylethylenediamine. This compound was found to form octahedral complexes with either cobalt(II) or copper(II) chloride, wherein all of the coordination sites of the metal ion are occupied by a ligating atom of the macrocycle. In addition several other compounds of this type have been synthesized and their complexation properties studied. A few cryptands have been reported, accompanied by data on their complexation properties. Two main reaction pathways were utilized to acquire the desired macrocycles: (1) a one-pot nucleophilic substitution reaction where six bonds are formed in one reaction, and (2) a quaternization-demethylation sequence where in a stepwise manner the bridges are introduced into the macrocyclic framework. The demethylations were accomplished by the use of L-Selectride(\u27(REGTM)) which quantitative and selectively removes methyl groups from a quaternary ammonium salt. Some of the cryptands synthesized have exhibited unusual structural properties and the effect of these structural properties on these macrocycles complexation properties have been studied. Their spectral and physical properties have also been reported

A motivational perspective on caregiver psychological distress

For many people, providing care for a seriously ill family member is a major life event that may disrupt their life and personal goals. Research has demonstrated the experience of such events is often associated with increased symptoms of depression, stress, and anxiety. Although many researchers have examined factors that influence this relation, few have explored it from a motivational perspective. Therefore, the goal of the present study was to examine the influence of self-regulatory processes and motivational orientation on the relations between burden (caregiver and objective burden) and psychological distress (defined as the experience of symptoms of depression, anxiety, and stress). Caregivers of adult family members diagnosed with cancer in the past three years were asked to complete a battery of questionnaires on psychological distress, caregiver burden, objective burden, goal adjustment and regulatory focus orientation. It was predicted that caregiver burden would partially mediate the relation between objective burden and caregiver psychological distress. Furthermore, based on the notion of regulatory fit, the strength of the relation between objective burden and caregiver burden would be greater for caregivers who tend to exhibit a weaker prevention focus than a stronger prevention focus. Lastly, it was hypothesized that the strength of the relation between caregiver burden and psychological distress would be greater for caregivers who report a greater inability to disengage from goals than caregivers who report a greater ability to disengage from goals. Results suggested that objective burden is associated with psychological distress through caregiver burden. Inconsistent with our hypotheses, promotion focus, instead of prevention focus, moderated the relation between objective burden and caregiver burden. Lastly, findings suggest that an ability to disengage from goals alleviates symptoms of anxiety and stress, and an ability to disengage from goals alleviates symptoms of anxiety and stress, and an ability to reengage in goals alleviates symptoms of depressed mood

Inspiration or defeat: the motivational and evaluative impact of social comparison on dysphoric individuals

People compare themselves to others in order to evaluate their abilities and opinions, yet the literature is mixed on how these social comparisons impact people's emotions, self-evaluation, and motivation. There were two primary aims of the present study. The first aim was to examine the impact of upward social comparisons (i.e., comparing oneself to someone who is believed to be more skilled or more fortunate) on self-evaluation and motivation. The second aim was to examine the influence of dysphoria in the relation between social comparison and both self-evaluation and motivation after partialling out the effects of self-esteem. Undergraduate students varying in levels of dysphoria were asked to read either an impressive student resume (upward comparison) or an average student resume (lateral comparison) prior to answering other- and self-evaluation questions and performing a brief anagram task to assess motivation. We predicted that after partialling out the effects of self-esteem, people who report higher dysphoria will evaluate themselves more negatively following an upward (but not a lateral) comparison than people who report lower dysphoria. We also predicted that after partialling out the effects of self-esteem, people who report higher dysphoria will display less motivation, as evidenced by correctly solving fewer anagrams, following an upward (but not a lateral) comparison than people who report lower dysphoria will. Results did not show a significant interactive effect of dysphoria on either the relation between social comparison and self-evaluation or the relation between social comparison and motivation. However, results did indicate a main effect of self-esteem (ß = .71, p < .001) and comparison (ß = -.13, p < .05) on self-evaluation