USE OF TARTARIC ACID AND ISOPROPYL ALCOHOL IN THE REDUCTION OF HEXAVALENT CHROMIUM AND APPLICATION TO CHROMIUM CONTAMINATED SOILS AND CHROMITE ORE PROCESSING RESIDUE

Although chromium (Cr) is a naturally occurring metal, in the oxidation state +(VI), it is a health concern when present in soils and natural waters due to its solubility and toxicity. Tartaric acid and isopropyl alcohol were evaluated for reduction of Cr(VI) at environmentally relevant pH values, in the presence of soils, and from chromite ore processing residue (COPR). Soil samples were taken from profiles located in delineations of five soil mapping units in Maryland, USA: Christiana-Russett Complex, Askecksy, Annapolis, Jackland, and Ingleside. In solution, the rate of reduction of Cr(VI) by the tartaric acid-Cr-isopropyl alcohol complex was lowered from 0.128 to 0.011 h-1 as pH was raised from 3.0 to 5.0; however, in the presence of the Russett and Jackland soils, the rates of reduction were 0.037 and 0.020 h-1, respectively despite pH values of 5.3 and 5.0. In addition to Cr(VI) reduction, 97.6 and 89.9 µM Mn(II), and 427 and 67.6 µM Fe(II) were solubilized from the Russett and Jackland soils, respectively. Adding soluble Mn2+ and Fe3+ to the five soils with tartaric acid and isopropyl alcohol enhanced reduction of Cr(VI) in all soils, with the addition of Mn2+ enhancing reduction by an additional 0.27 mM Cr(VI) in the Jackland soil and to 1.46 mM in the Downer soil. Furthermore, the addition of tartaric acid and isopropyl alcohol to Mn-oxide coated sand (1.8x10-1 µmol Mn/mg) showed reductive dissolution of Mn(III,/IV)(hydr)oxides, and the resulting Mn(II) enhanced reduction to 1.24 mM (62%) of Cr(VI). When applied to COPR, tartaric acid-Cr-isopropyl alcohol or tartaric acid-Cr-Mn complexes reduced 0.3 mM (30%) Cr(VI), although when COPR was mixed with the Atsion, Collington, or Russett soils, pH values remained below 5.0 and 0.84 mM (84%) of the Cr(VI) was reduced. This work showed that a tartaric acid and isopropyl alcohol solution reductively dissolves Mn(III,/IV)(hydr)oxides from soils, and the resulting Mn(II) enhances reduction of Cr(VI), which can be potentially applied to the reduction of COPR-derived Cr(VI) in a soil remediation strategy

Affective states contribute to trait reports of affective well-being

Asking people to provide global judgments, or trait reports, of their affective experience is a standard method for assessing trait affective well-being, with countless applications in the social sciences. Trait reports reflect numerous influences that generally go unnoticed. Although state affect is a highly plausible candidate for such influences, this source of unwanted variance does not receive much attention and is usually not controlled for in empirical studies. Using 100-day data from the COGITO study, we provide direct and strong evidence that trait reports of affect depend on how people feel at the time they provide the evaluations (i.e., their affective state). For example, participants experiencing more positive affect on a specific day relative to their individual mean also provide more positive ratings of their global affective experience. Furthermore, we found that current affect influences trait ratings in a surprisingly differentiated way—those particular facets of affect that are more/less prevalent at a certain moment are believed to occur more/less often in general. We stress the need for repeated observations within individuals to estimate state contributions to standard assessments of trait affect, to distinguish between state and trait in psychological assessment, and to achieve good indicators of affective experiences in the social and medical sciences

Neural correlates of up-regulating positive emotions in fMRI and their link to affect in daily life

Emotion regulation is typically used to down-regulate negative or up-regulate positive emotions. While there is considerable evidence for the neural correlates of the former, less is known about the neural correlates of the latter—and how they are associated with emotion regulation and affect in daily life. Functional magnetic resonance imaging (fMRI) data were acquired from 63 healthy young participants (22 ± 1.6 years, 30 female), while they up-regulated their emotions to positive and neutral images or passively watched them. The same participants’ daily affect and emotion regulation behavior was measured using experience sampling over 10 days. Focusing on the ventral striatum (VS), previously associated with positive affective processing, we found increased activation during the up-regulation to both positive and neutral images. VS activation for the former positively correlated with between- and within-person differences in self-reported affective valence during fMRI but was not significantly associated with up-regulation in daily life. However, participants with lower daily affect showed a stronger association between changes in affect and activation in emotion-related (medial frontal and subcortical) regions—including the VS. These results support the involvement of the VS in up-regulating positive emotions and suggest a neurobehavioral link between emotion-related brain activation and daily affect

Toward a unified framework for the study of between-person and within-person structures : Building a bridge between two research paradigms

The vast majority of empirical research in the behavioral sciences is based on the analysis of between-person variation. In contrast, much of applied psychology is concerned with the analysis of variation within individuals. Furthermore, the mechanisms specified by psychological theories generally operate within, rather than across, individuals. This disconnect between research practice, applied demands, and psychological theories constitutes a major threat to the conceptual integrity of the field. Following groundbreaking earlier work, we propose a conceptual framework that distinguishes within-person (WP) and between-person (BP) sources of variation in psychological constructs. By simultaneously considering both sources of variation, it is shown how to identify possible reasons for nonequivalence of BP and WP structures as well as establishing areas of convergence. For this purpose, we first introduce the concept of conditional equivalence as a way to study partial structural equivalence of BP and WP structures in the presence of unconditional nonequivalence. Second, we demonstrate the construction of likelihood planes to explore the causes of structural nonequivalence. Third, we examine 4 common causes for unconditional nonequivalence autoregression, subgroup differences, linear trends, and cyclic trends-and demonstrate how to account for them. Fourth, we provide an empirical example on BP and WP differences in attentiveness

The Fire-Oak Literature of Eastern North America: Synthesis and Guidelines

Guidelines for using prescribed fire to regenerate and restore upland oak forests, woodlands, and savannas in eastern North America were developed by synthesizing the results of more than 100 scientific publications. The first four chapters provide background information on the values of oak ecosystems, eastern fire history, oak’s adaptations to fire, and the findings of fire-oak research conducted over the past 50 years. The final chapter synthesizes that background information into guidelines that explain how to use prescribed fire to facilitate oak seedling establishment, release oak reproduction from competing mesophytic hardwoods, and rehabilitate open oak woodlands, oak savannas, and scrub oak communities. A reference section is also provided for readers desiring to delve more deeply into the associations between periodic fire and oak forests, woodlands, and savannas

微細CMOSデバイスの信頼性モデリングの研究

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