Sulfur-Modulated Tin Sites Enable Highly Selective Electrochemical Reduction of CO2 to Formate

Electrochemical reduction of carbon dioxide (CO2RR) to formate provides an avenue to the synthesis of value-added carbon-based fuels and feedstocks powered using renewable electricity. Here, we hypothesized that the presence of sulfur atoms in the catalyst surface could promote undercoordinated sites, and thereby improve the electrochemical reduction of CO2 to formate. We explored, using density functional theory, how the incorporation of sulfur into tin may favor formate generation. We used atomic layer deposition of SnSx followed by a reduction process to synthesize sulfur-modulated tin (Sn(S)) catalysts. X-ray absorption near-edge structure (XANES) studies reveal higher oxidation states in Sn(S) compared with that of tin in Sn nanoparticles. Sn(S)/Au accelerates CO2RR at geometric current densities of 55 mA cm−2 at −0.75 V versus reversible hydrogen electrode with a Faradaic efficiency of 93%. Furthermore, Sn(S) catalysts show excellent stability without deactivation (<2% productivity change) following more than 40 hours of operation. With rapid advances in the efficient and cost-effective conversion of sunlight to electrical power, the development of storage technologies for renewable energy is even more urgent. Using renewable electricity to convert CO2 into formate simultaneously addresses the need for storage of intermittent renewable energy sources and the need to reduce greenhouse gas emissions. We report an increase of greater than 4-fold in the current density (hence the rate of reaction) in formate electrosynthesis compared with relevant controls. Our catalysts also show excellent stability without deactivation (<2% productivity change) following more than 40 hours of operation. The electrochemical reduction of carbon dioxide (CO2RR) offers a compelling route to energy storage and high-value chemical manufacture. The presence of sulfur atoms in catalyst surfaces promotes undercoordinated sites, thereby improving the electrochemical reduction of CO2 to formate. The resulting sulfur-modulated tin catalysts accelerate CO2RR at geometric current densities of 55 mA cm−2 at −0.75 V versus RHE with a Faradaic efficiency of 93%

The influence of symptom attributional style and beliefs about viruses on the reporting of symptoms during and after infection

Previous research has found that attributional style and beliefs people have about viruses can be related to symptom reporting and presentation. Especially in the area of chronic fatigue it has been shown repeatedly that patients' attribution of their illness is related to a worse outcome. This study investigates the influence of symptom attributional style and beliefs about the power of viruses on symptom reporting in people who think they suffer from influenza, using the Symptom Interpretation Questionnaire (SIQ) and the Viral Infection Research into Attitudes Scale (VIRAS). A visual analogue scale was used to measure the number and severity of physical and psychological symptoms of influenza. A follow-up was carried out to measure levels of fatigue after illness, using the Fatigue Scale. Results are presented and discussed, and conclusions are drawn

Suppressed absolute negative conductance and generation of high-frequency radiation in semiconductor superlattices

We show that space-charge instabilities (electric field domains) in semiconductor superlattices are the attribute of absolute negative conductance induced by small constant and large alternating electric fields. We propose the efficient method for suppression of this destructive phenomenon in order to obtain a generation at microwave and THz frequencies in devices operating at room temperature. We theoretically proved that an unbiased superlattice with a moderate doping subjected to a microwave pump field provides a strong gain at third, fifth, seventh, etc. harmonics of the pump frequency in the conditions of suppressed domains.Comment: 8 pages. Development of cond-mat/0503216 . Version 2: Final version, erratum is include

A Preliminary Study of a Job Analytic Inventory Derived From a Behavioral Consistency Method for Assessing Intrinsic Motivation

The research question for this study asked if the Job Specifications Inventory (JSI) had acceptable internal reliability and an ability to differentiate among occupational groups. The JSI was designed to have subject matter experts rate the importance of skill, content, context, relationship and work focus requirements of jobs or occupations. The JSI used a taxonomy of 268 behavioral elements derived from the content analyses of satisfying achievements reported by a large, diverse clientele. A clinical-type behavioral consistency method was used to extract performance dimensions from clients\u27 achievements to build the taxonomy. The achievement-based taxonomy was seen as potentially enhancing productivity for employers and job satisfaction for employees. The JSI was intended to be used in conjunction with behavioral consistency methods to address individual and organizational problems associated with person-job fit. The relationship between persons and jobs was viewed as having important consequences for individuals, organizations and society. Person-job fit has been linked to employment outcomes associated with productivity, job satisfaction, and work-related stress. A content validity strategy guided JSI development to support fairness and to avoid adverse impact in employment decisions. The JSI was administered to 614 subject matter experts in seven occupational groups--certified public accountants, civil engineers, elementary teachers, insurance sales agents, musicians, personnel managers, and secretaries. Internal reliability estimates ranged from.96 to.98 across occupational groups and from.72 to.96 for JSI parts by occupation. Ward\u27s cluster analysis method suggested a seven-cluster solution against the seven occupational groups used as external classification criteria, but occupational overlap did occur within clusters. The 268 JSI variables were reduced to 38 scales and examined by factor analysis for structural properties. Seven factors were identified with loadings above.40 and used in further evaluation. Analysis of variance found significant differences in scores among occupational groups, clusters and JSI parts. Multiple comparison tests showed significant interaction effects among occupations and clusters by JSI parts and by JSI factors. Results suggested that the JSI displayed acceptable internal reliability and showed discriminating ability to differentiate occupational groups. The statistically significant differences in ratings among groups and clusters were attributable to the structural properties of the inventory and provided evidence for construct validity. The JSI could have utility for managers in behavioral description interviewing to enhance selection and placement decisions. Additionally, individuals could use the JSI to analyze job specifications for strengthening career decisions. Future use could involve the definition of important worker specifications in occupations to enhance mobility for workers and transportability of skills for employers

An Analysis of Urban Higher Education CEO\u27s Perceptions of Critical Leadership Behaviors

The research question for this study asked if CEO\u27s (Chief Executive Officers) of urban higher education institutions hold the same values and beliefs as those attributed to business and industry CEO\u27s through the business literature. Through survey methodology, the analysis of urban higher education CEO\u27s perceptions of critical leadership behaviors revealed very similar belief patterns. The primary discrepancies between the research group and their industry counterparts lie in the degree to which critical behaviors are espoused and in the acceptance of transformational leadership as a proactive model for effective organizational change. The responses to the open-ended portion of the questionnaire gave a clear picture of the kinds of training CEO\u27s consider to be important. The Likert scale items revealed that urban education CEO\u27s espouse the transformational leadership concept yet are tentative about empowering staff and aligning the organizational structure to facilitate a participative management model. Entrepreneurship and risk taking activities are embraced somewhat tentatively also which would serve to inhibit creativity and innovation within the organization. The traditional emphasis on academic culture, symbols and the president as leader may be instrumental in encouraging the belief that CEO\u27s should be charismatic and visionary, yet without changing organizational structure and empowering employees, the concept of leadership remains in the traditional domain. It has been established that urban education CEO\u27s do hold similar beliefs as their business counterparts. The literature search also revealed that many environmental and business conditions are also similar. It is therefore recommended that further research be conducted to identify ways in which transformational leadership methods could best benefit the urban higher education milieu