Environmental and Social Disclosures and Firm Risk

ArticleWe examine the link between a firm’s environmental (E) and social (S) disclosures and measures of its risk including total, systematic, and idiosyncratic risk. While we do not find any link between a firm’s E and S disclosures and its systematic risk, we find a negative and significant association between these disclosures and a firm’s total and idiosyncratic risk. These are novel findings and are consistent with the predictions of the stakeholder theory and the resource based view of the firm suggesting that firms which make extensive and objective E and S disclosures promote corporate transparency that can help them build a positive reputation and trust with its stakeholders, which in turn can help mitigate the firm’s idiosyncratic/operational risk. These findings are important for all corporate stakeholders including managers, employees, and suppliers who have a significant economic interest in the survival and success of the firm

Boron-carbon-nitrogen foam surfaces for thermal physisorption applications

A surface chemical treatment of highly porous carbon foams was adopted to synthesize boron-carbon-nitrogen (B-C-N) foams for thermal energy storage and release using an adsorption/desorption cycle with lightweight hydrocarbons. Microwave treatment in boric acid and urea was used to modify carbon foams with a B-C-N surface. Depending on the initial carbon foam state, B-C-N surface layers were produced with both amorphous and crystalline structures. The resultant B-C-N foams were characterized by TEM, XPS, XRD, FESEM and Raman measurements to quantify their stoichiometry, structure, and morphology. Adsorption enthalpy with methanol and thermal stability of foams was analyzed with DSC and TGA respectively. Thermal conductivity was measured by a transient laser flash technique. Results indicate that the crystalline graphitic carbon foam produces superior B-C-N surfaces compared to amorphous carbon foam. The crystalline B-C-N foams are found to provide the highest adsorption capacity, better thermal and oxidation stability. (c) 2012 Elsevier B.V. All rights reserved

Improved Dehydrogenation Properties of Ti-Doped LiAlH4: Role of Ti Precursors

The dehydrogenation properties of LiAlH4 doped with different Ti precursors (Ti, TiO2, and TiCl3) via ball milling are investigated. The results not only show significant decreases in the decomposition temperatures (T-dec) and activation energies (E-A) of the first two dehydrogenation reaction steps of LiAlH4 by doping with TiO2 or TiCl3, but also reveal how each Ti precursor affects the dehydrogenation process. Although doping LiAlH4 with TiCl3 induced the largest decrease in T-dec and E-A, TiO2-doped LiAlH4 produced a decrease in T-dec and E-A that is quite close to the TiCl3-doped sample as well as superior short-term stability, suggesting that doping with TiO2 has certain advantages over doping with TiCl3. Further, the underlying mechanisms associated with the Ti precursors during the dehydrogenation reaction of LiAlH4 have been studied using quasi in situ X-ray photoelectron spectroscopy. The results reveal that the Ti4+ and Ti3+ reduction processes and the segregation of Li cations to the surface of LiAlH4 during ball milling play critical roles in the improved dehydrogenation properties observed