The effect of surface and hydrodynamic forces on the shape of a fluid drop approaching a solid surface

This paper describes an experiment designed to measure surface and hydrodynamic forces between a mercury drop and a flat mica surface immersed in an aqueous medium. An optical interference technique allows measurement of the shape of the mercury drop as well as its distance from the mica, for various conditions of applied potential, applied pressure, and solution conditions. This enables a detailed exploration of the surface forces, particularly double-layer forces, between mercury and mica. A theoretical analysis of drop shape under the influence of surface forces shows that deformation of the drop is a sensitive indicator of the forces, as well as being a very important factor in establishing the overall interaction between the solid and the fluid.

Effect of surface roughness and electrostatic surface potentials on forces between dissimilar surfaces in aqueous solution

The first surface force measurements under electrochemical potential control between a metal and a ceramic surface across a liquid medium (water) are reported. Our experiments also investigate and reveal how increasing levels of surface roughness and dissimilarity between the potentials of the interacting surfaces influence the strength and range of electric double layer, van der Waals, hydration, and steric forces and how this contributes to deviations from DLVO theory at small distances within aqueous solution.

The relevance and irrelevance of the brand for small and medium wine enterprises

Given the proliferation of wine brands, developing a brand without understanding its impact on wine choice is a risky business; particularly for SMEs with limited financial resources.

This paper fills an important gap in the wine marketing literature, particularly as it relates to SMEs in the sector, by investigating the effect of the brand on wine choice. Surveying a range of wine consumers, it was found that while the brand was relevant in wine choice the weighted importance of the brand elements changed across consumption situations. This novel finding should assist SMEs to grow their businesses beyond the traditional cellar door.

Oxygen reduction reaction activity of La-based perovskite oxides in alkaline medium : a thin-film rotating ring-disk electrode study

In this work, LaMO₃ and LaNi_0.5M_0.5O₃ (M = Ni, Co, Fe, Mn and Cr) perovskite oxide electrocatalysts were synthesized by a combined ethylenediaminetetraacetic acid-citrate complexation technique and subsequent calcinations at 1000 °C in air. Their powder X-ray diffraction patterns demonstrate the formation of a specific crystalline structure for each composition. The catalytic property of these materials toward the oxygen reduction reaction (ORR) was studied in alkaline potassium hydroxide solution using the rotating disk and rotating ring-disk electrode techniques. Carbon is considered to be a crucial additive component because its addition into perovskite oxide leads to optimized ORR current density. For LaMO₃ (M = Ni, Co, Fe, Mn and Cr)), in terms of the ORR current densities, the performance is enhanced in the order of LaCrO₃, LaFeO₃, LaNiO₃, LaMnO₃, and LaCoO3. For LaNi_0.5M_0.5O₃, the ORR current performance is enhanced in the order of LaNi_0.5Fe_0.5O₃, LaNi_0.5Co_0.5O₃, LaNi_0.5Cr_0.5O₃, and LaNi_0.5Mn_0.5O₃. Overall, LaCoO₃ demonstrates the best performance. Most notably, substituting half of the nickel with cobalt, iron, manganese, or chromium translates the ORR to a more positive onset potential, suggesting the beneficial catalytic effect of two transition metal cations with Mn as the most promising candidate. Koutecky–Levich analysis on the ORR current densities of all compositions indicates that the four-electron pathway is favored on these oxides, which are consistent with hydroperoxide ion formation of <2%.

Carbon dioxide emission mitigation and disclosures : the size effect

The analysis provided in this research ainis to improve the understanding of the structure and nature of organisations in the transport industry so that policy-makers and researchers can be informed about the impact of size of an organisation on its preparation for the transition to a low carboneconomy. Descriptive and infetential are calculated to aid in understanding how organisations manage their C02mitigation action and carbon emission disclosure. It is noted that small and medium sized companies appear to be less financially capable of responding to the challenges of transiting to a low carbon environment that large companies.

Effect of cell-surface components and metabolites of lactic acid bacteria and probiotic organisms on cytokine production and induction of CD25 expression in human peripheral mononuclear cells

In the current study, the relative contribution of cell-surface components (CSC) and cell-free supernatants (CFS) in the immuno-modulatory properties of 17 strains of probiotic and lactic acid bacteria (LAB) was assessed. The production of pro- and antiinflammatory cytokines including IL-2, IL-4, IL-10, IL-12 p70, IFN-γ, tumor necrosis factor-α (TNF-α), and transforming growth factor-β was measured at different time points after stimulation of buffy coat derived-peripheral blood mononuclear cells (PBMC) from healthy donors with CSC and CFS of probiotic and LAB. Results showed that CSC of probiotic and LAB strains induced production of T helper 1 and 2 type cytokines. Transforming growth factor-β was stimulated at highest concentrations, followed by IL-10 and TNF-α. The CFS of all tested bacterial strains induced PBMC for significantly high levels of IL-10 secretion compared with unstimulated cells, but the values were less than lipopolysaccharide-stimulated cells. Cytokines due to CFS stimulation showed declined concentration for IL-2, TNF-α, and IL-4, and complete disappearance of IL-12, IFN-γ, and transforming growth factor-β in the cultured medium at 96 h of incubation. Results of cytokine data demonstrate proinflammatory TNF-α immune responses are mainly directed through cell-surface structures of probiotic and LAB, but antiinflammatory immune responses are mediated both by metabolites and cell-surfaces of these bacteria. The induction of CD4(+)CD25(+) regulatory T cells after stimulation of PBMC with CSC and CFS of probiotic and LAB showed regulatory T cell activity appeared to be influenced both by the CSC and metabolites, but was principally triggered by cell surfaces of probiotic and LAB strains.

The effect of auditor quality on financing decisions

We present a model and provide empirical evidence showing that auditor quality affects the financing decisions of companies, and that higher audit quality reduces the impact of market conditions on client financial decisions and capital structure. Consistent with our analytical predictions, we find that companies audited by Big 6 firms are more likely to issue equity as opposed to debt than are those audited by small audit firms. We also find that companies audited by Big 6 auditors are able to make larger equity issues than are those audited by small auditors, but the difference narrows when market conditions improve. Additional results show that the debt ratios of companies decrease less in response to favorable market conditions when auditor quality is high, at least over the medium term.