Preparation and electrochemical studies of metal–carbon composite catalysts for small-scale electrosynthesis of H2O2

Numerous transition metal–carbon composite catalysts (M = V, Zn, Ni, Sn, Ce, Ba, Fe, Cu) have been synthesized and tested for electroreduction of O₂ to H₂O₂, The activity and selectivity of all synthesized catalysts for electrosynthesis of H₂O₂ were determined by the rotating ring-disk electrode method in acidic and neutral electrolytes. The Co-based catalysts in general showed the highest activity towards H₂O₂ formation. Experiments with different loading contents of Co showed that the activation overpotential losses of oxygen reduction to H₂O₂ reduces as loading increases to about 4 wt% Co. Addition of Co beyond this level did not seem to impact the overpotential losses. The cobalt-based catalysts, were spray-coated onto 120 μm thick Toray^® graphite substrates, and were studied in bulk electrolysis cells for up to 100 h at potentiostatic conditions (0.25 V vs. RHE) in pH 0, 3, and 7 electrolytes. At (25 °C and 1 bar) with a catalysts loading of about and using dissolved O₂ in 0.5 M H₂SO₄, typical H₂O₂ electrosynthesis rates of about were reached with current efficiencies of about 85 ± 5% at 0.25 V (vs. RHE).     

What do people value when they negotiate? Mapping the domain of subjective value in negotiation.

Four studies support the development and validation of a framework for understanding the range of social psychological outcomes valued subjectively as consequences of negotiations. Study 1 inductively elicited and coded elements of subjective value among students, community members, and practitioners, revealing 20 categories that theorists in Study 2 sorted into 4 underlying subconstructs: Feelings About the Instrumental Outcome, Feelings About the Self, Feelings About the Negotiation Process, and Feelings About the Relationship. Study 3 proposed a new Subjective Value Inventory (SVI) and confirmed its 4-factor structure. Study 4 presents convergent, discriminant, and predictive validity data for the SVI. Indeed, subjective value was a better predictor than economic outcomes of future negotiation decisions. Results suggest the SVI is a promising tool to systematize and encourage research on subjective outcomes of negotiation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Parametric instability of belts: theory and experiments

In this paper, the dynamic stability of a power transmission belt excited by an eccentric pulley is investigated. A theoretical model is developed to predict the belt response: simply supported boundary conditions are considered, neglecting the pulley curvature, and including the effect of the lower belt span. The transverse displacement field is expanded into sine series and the Galerkin method is applied to reduce the partial differential equation (PDE) into a set of ordinary differential equations. In order to forecast the belt response, the elastic characteristics only of the belt must be provided to the theoretical model. An experimental investigation is performed on a belt-pulley system with a pulley eccentricity; a laser displacement transducer is used to measure the transverse displacement. The combination of a direct and a parametric excitation is analyzed in detail. Interesting post-critical nonlinear dynamic behaviors are found: sub-harmonic responses and quasi-periodic motions seem to coexist, depending on the initial conditions. Experiments confirm the numerical results, thus validating the present theoretical model.     

Neuroimaging evidence for agenda-dependent monitoring of different features during short-term source memory tests.

A short-term source monitoring procedure with functional magnetic resonance imaging assessed neural activity when participants made judgments about the format of 1 of 4 studied items (picture, word), the encoding task performed (cost, place), or whether an item was old or new. The results support findings from long-term memory studies showing that left anterior ventrolateral prefrontal cortex (PFC) is engaged when people make source attributions about reflectively generated information (cognitive operations, conceptual features). The findings also point to a role for right lateral PFC in attention to perceptual features and/or familiarity in making source decisions. Activity in posterior regions also differed depending on what was evaluated. These results provide neuroimaging evidence for theoretical approaches emphasizing that agendas influence which features are monitored during remembering (e.g., M. K. Johnson, S. Hashtroudi, & D. S. Lindsay, 1993). They also support the hypothesis that some of the activity in left lateral PFC and posterior regions associated with remembering specific information is not unique to long-term memory but rather is associated with agenda-driven source monitoring processes common to working memory and long-term memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Catalytic sequential reactions involving palladacycle-directed aryl coupling steps

Catalytic methods are important tools for the synthesis of C-C bonds under mild and ambient conditions. Palladium chemistry predominates in this area because it offers the opportunity to form several different types of bonds in one pot. Palladium can also tolerate a variety of functional groups. Among the many investigations of catalytic aryl-aryl couplings, the most successful technique has been the Suzuki reaction, which uses an arylboronic acid to attack an aryl-Pd bond. This Account reports our methodology, based on the cooperative action of Pd and norbornene, that achieves selective aryl-aryl coupling through C-halide and C-H activation. We are primarily interested in Pd-catalyzed sequential reactions. These reactions combine palladium as an inorganic catalyst and a strained olefin such as norbornene as an organic catalyst and can lead to biphenyl derivatives. While the palladium facilitates C-C bond formation through C-halide and C-H activation, the norbornene contributes to the construction of a palladacycle, an intermediate structure that controls and directs the subsequent reaction steps selectively. To achieve regioselective arylation at the carbon ortho to the original C-halide bond, palladacycles require an additional ortho substituent (R(1)). The palladacycle opens, giving rise to a biphenylylnorbornylpalladium complex. Because of the steric hindrance exerted by the two ortho groups, norbornene deinsertion readily occurs to form a biphenylylpalladium complex. Thus, norbornene acts as a removable scaffold. We used this biphenylylpalladium species to form C-C (with olefins, alkynes, or arylboronic acids) or C-H bonds (by hydrogenolysis). Using nonidentical aryl or heteroaryl halides, we also formed a biaryl-bonded Pd species able to undergo the final termination reaction (C-C, C-N, or C-O bond formation) either inter- or intramolecularly. We used this method to synthesize a variety of aromatic and heteroaromatic compounds. We also obtained the key metallacycle able to selectively direct the reactions by replacing norbornene with an aryl-bonded aminocarbonyl group. This method provided a diverse series of condensed heterocycles.     

Palladium‐Catalyzed Synthesis of Selectively Substituted Phenanthridine Derivatives

Selectively substituted phenanthridine derivatives are obtained by a facile reaction of o‐alkylated aryl iodides, o‐bromoarenesulfonylanilines and activated olefins in the presence of palladium and norbornene as catalysts. The reaction takes place under mild conditions to give the products in satisfactory yields using readily available starting materials.     

Parent and therapist evaluation of behavior therapy in a child psychological clinic.

Obtained evaluations from the parents of 70 children who were treated by psychological interns being trained in behavior therapy. Therapist ratings of specific problem improvement were obtained at close of therapy. Improvement ratings of the same specific problems were obtained from parents approximately 6 mo later. Classification of an S as improved or unimproved depended on the averages of both the therapist and parent ratings of the presenting problems. This procedure indicated overall improvement in 87 and 90% of the cases, based on therapist and parent averages, respectively. Therapists rated 80% of all specific problems improved at termination, as compared to 77% of problems improved as rated by parents at follow-up. Correlation between the improvement ratings of each problem by parent and therapist was highly significant (r = .51). 96% of the parents liked their therapists, and personal characteristics most frequently noted by the parents were warmth, understanding, and sincere interest in the S. The high improvement rates reported by therapists and parents are discussed in regard to previous therapy outcome studies with children. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Toward a dialect theory: Cultural differences in the expression and recognition of posed facial expressions.

Two studies provided direct support for a recently proposed dialect theory of communicating emotion, positing that expressive displays show cultural variations similar to linguistic dialects, thereby decreasing accurate recognition by out-group members. In Study 1, 60 participants from Quebec and Gabon posed facial expressions. Dialects, in the form of activating different muscles for the same expressions, emerged most clearly for serenity, shame, and contempt and also for anger, sadness, surprise, and happiness, but not for fear, disgust, or embarrassment. In Study 2, Quebecois and Gabonese participants judged these stimuli and stimuli standardized to erase cultural dialects. As predicted, an in-group advantage emerged for nonstandardized expressions only and most strongly for expressions with greater regional dialects, according to Study 1. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

DSM-IV criteria for generalized anxiety disorder in older adults: Distinguishing the worried from the well.

This study compared 36 older adults with generalized anxiety disorder (GAD), 22 older adults with subsyndromal anxiety symptoms, and 32 normal controls on criteria of the Diagnostic and Statistical Manual of Mental Disorders (4th ed.) for GAD. GAD patients reported more frequent and uncontrollable worry, somewhat different worry content, higher prevalence of most associated symptoms, and more distress or impairment than the subsyndromal group or normal controls. Individuals with subsyndromal anxiety reported more excessive, frequent, and uncontrollable worry than asymptomatic individuals, along with more sleep disturbance, fatigue, and distress or impairment. Results indicate that the key features of late-life GAD are distress and impairment, frequency and uncontrollability of worry, muscle tension, and sleep disturbance and that clinicians treating older adults with GAD should monitor and treat residual symptoms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Predicting workplace outcomes from the ability to eavesdrop on feelings.

Emotion recognition, the most reliably validated component within the construct of emotional intelligence, is a complicated skill. Although emotion recognition skill is generally valued in the workplace, "eavesdropping," or relatively better recognition ability with emotions expressed through the less controllable "leaky" nonverbal channels, can have detrimental social and workplace consequences. In light of theory regarding positive emotion in organizations, as well as research on the consequences of perceiving negative information, the authors hypothesized and found an interaction between nonverbal channel and emotional valence in predicting workplace ratings from colleagues and supervisors. Ratings were higher for eavesdropping ability with positive emotion and lower for eavesdropping ability with negative emotion. The authors discuss implications for the complexity of interventions associated with emotional intelligence in workplace settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)