Nature of hydrogen atom trapped inside palladium lattice

Colloid of palladium nanoparticles has been prepared by the Solvated Metal Atom Dispersion (SMAD) method. Reaction of Pd(0) nanopowder obtained upon precipitation from the colloid, with ammonia borane (H3N center dot BH3, AB) in aqueous solutions at room temperature results in the generation of active hydrogen atoms. The active hydrogen atoms either combine with one another resulting in H-2 evolution or diffuse into the Pd lattice to afford PdHx. Diffusion of hydrogen atoms leads to an expansion of the Pd lattice. The diffused hydrogen atoms are distributed uniformly over the entire particle. These features were established using powder XRD and electron microscopy studies. The H-1 NMR spectral studies of PdHx before and after desorption of H-2 revealed that the hydrogen atoms trapped inside Pd lattice are hydridic in nature. Desorption of hydrogen from PdHx did not result in complete reversibility suggesting that some hydrogen atoms are strongly trapped inside the Pd lattice. (C) 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.

Publishing in the Networked World: Transforming the Nature of Communication, 14th International Conference on Electronic Publishing 16-18 June 2010, Helsinki, Finland

The title of the 14th International Conference on Electronic Publishing (ELPUB), “Publishing in the networked world: Transforming the nature of communication”, is a timely one. Scholarly communication and scientific publishing has recently been undergoing subtle changes. Published papers are no longer fixed physical objects, as they once were. The “convergence” of information, communication, publishing and web technologies along with the emergence of Web 2.0 and social networks has completely transformed scholarly communication and scientific papers turned to living and changing entities in the online world. The themes (electronic publishing and social networks; scholarly publishing models; and technological convergence) selected for the conference are meant to address the issues involved in this transformation process. We are pleased to present the proceedings book with more than 30 papers and short communications addressing these issues. What you hold in your hands is a by-product and the culmination of almost a Year long work of many people including conference organizers, authors, reviewers, editors and print and online publishers. The ELPUB 2010 conference was organized and hosted by the Hanken School of Economics in Helsinki, Finland. Professors Turid Hedlund of Hanken School of Economics and Yaşar Tonta of Hacettepe University Department of Information Management (Ankara, Turkey) served as General Chair and Program Chair, respectively. We received more than 50 submissions from several countries. All submissions were peer-reviewed by members of an international Program Committee whose contributions proved most valuable and appreciated. The 14th ELPUB conference carries on the tradition of previous conferences held in the United Kingdom (1997 and 2001), Hungary (1998), Sweden (1999), Russia (2000), the Czech Republic (2002), Portugal (2003), Brazil (2004), Belgium (2005), Bulgaria (2006), Austria (2007), Canada (2008) and Italy (2009). The ELPUB Digital Library, http://elpub.scix.net serves as archive for the papers presented at the ELPUB conferences through the years. The 15th ELPUB conference will be organized by the Department of Information Management of Hacettepe University and will take place in Ankara, Turkey, from 14-16 June 2011. (Details can be found at the ELPUB web site as the conference date nears by.) We thank Marcus Sandberg and Hannu Sääskilahti for copyediting, Library Director Tua Hindersson – Söderholm for accepting to publish the online as well as the print version of the proceedings. Thanks also to Patrik Welling for maintaining the conference web site and Tanja Dahlgren for administrative support. We warmly acknowledge the support in organizing the conference to colleagues at Hanken School of Economics and our sponsors.

Nature of corrosive and abrasive wear in ball mill grinding

Laboratory results of marked-ball wear tests are used to discuss the relative significance of corrosive and abrasive wear in wet grinding. The electrochemical mechanism was investigated by correlating the corrosive wear with the corrosion current obtained from polarization curves under abrasion. Slurry rheology governs the manner in which ground slurries coat grinding balls, thereby influencing not only the grinding efficiency but also abrasive wear. The effects of percent solids and a grinding aid are illustrated.

Nature of the copper species in superconducting YBa2Cu3O7

The nominal composition of YBa2Cu3O7 oxide suggests that 33% of the copper should be in the 3+ state. In structural studies3–5, Cu3+ and Cu2+ ions have been assigned specific sites based on their preferred coordinations, and many of the models of superconductivity also require the presence of Cu3+. Our studies however show that Cu is present only in the Cu1+ and Cu2+ states, the proportion of the former increasing with decreasing temperature. It appears that there is no clear experimental evidence for the presence of Cu3+ in YBa2Cu3O7.

Reactions of bis(isonitrosoethylacetoacetato)palladium(II) with straight chain aliphatic primary amines influence of concentration of the reacting amines on the nature of the products

Reactions of bis(isonitrosoethylacetoacetato)palladium(II), Pd(IEAA)2,with straight chain non-bulky alkylamines, RNH2(R = CH3, C2H5, n-C3H7or n-C4H9) in the mole ratio 1:1 gave bis (B-alkylisonitrosoethylacetoacetateimino)Palladium(II), Pd(R-IEAI)2. In this reaction the coordinated carbonyl groups of Pd(IEAA)2 undergo condensation with amines fo rming Schiff bases (>CNR). On the other hand, the reactions of Pd(IEAA)2 with a large excess of amine yielded N-alkylamido bridgedisonitrosoethylacetoacetatedipalladium(II), μ-(NHR)2[Pd(IEAA)]2 complexes. The complexes are characterized by elemental analyses, magnetic susceptib ility, i.r., p.m.r. and in some cases, nitrogen 1s X-ray photoelectron and mass spectral studies.

Theorizing the Nature of Reflection

For the past decades reflection has been the buzzword of adult and higher education. Reflection is facilitated in many practices and there is abundant research on the issue. Despite the popularity of the concept, the reasons why bringing about reflection in educational practices is difficult remain unclear. The prevailing theories inform of the process in its ideal form. However, to a great extent, they fail to offer conceptual tools for understanding and working with the actualities of reflection. The aim of the doctoral thesis was to explore the challenges and prerequisites of reflection in order to theorize the nature of reflection. By the term reflection it is here referred to becoming aware of and questioning the assumptions that orient our thinking, feelings and actions. The doctoral thesis consists of five studies that approach these questions from different viewpoints and within different contexts. The methods involve both a philosophical and an empirical approach. This multifaceted approach embodies the aim of both gaining a more thorough grasp of the phenomenon and to develop the methodology of researching reflection. The theory building is based on conceptual analysis and rational reconstruction (see Davia 1998; Habermas 1979; Rorty1984) of Mezirow s (1981; 1991; 2000; 2009) theory of transformative learning. In order to explore the aspects which, based on the analysis, appeared insufficiently considered within Mezirow s theory, Damasio s (1994; 1999; 2003; 2010) theory on emotions and consciousness as well as Clausewitz s (1985) view on friction are used as complementary theories. Empirical analyses are used in dialogue with the theoretical, in order to challenge and refine the emerging theorization. Reflection is examined in three different contexts; regarding university teachers pedagogical growth, involuntarily childless women recovering from a life-event crisis, and soldiers preparing to act in chaotic situations of the battlefield as well as recovering from it. The choice of these contexts is based on Mezirow s notion of disorienting dilemma as a trigger for reflection. This notion indicates that reflection may more naturally emerge in association to life-event crises or other cumulative sets of instances, which bring our worldview and beliefs under question. Nevertheless, reflection is often being promoted in educational contexts in which the trigger conditions may not readily prevail. These contextual issues as well as the differences between the facilitated and non-facilitated contexts have not, however, been considered in detail within the research on reflection (or transformative learning). The doctoral thesis offers a new perspective into reflection which, as a further development on Mezirow s transformative learning theory, theorizes the nature of reflection. The developed theory explicates the prerequisites and challenges to reflection. The theory suggests that the challenges of reflection are fundamentally connected to the way the biological life-support system affects our thinking through emotions. While depicting the mechanisms that function as a counterforce to reflection, the developed theory also opens a perspective for considering possibilities for carrying out reflection, and suggests ways to locate and deal with the assumptions to be reflected on. The basic dynamic of the challenges to reflection was explicated by conceptually bridging the gap between Mezirow s and Damasio s theories, through exploring the connections between the meaning perspective and the biological functions of emotions. The concepts of comfort zone and edge-emotions were formed so as to depict the emotional orientation of our thinking, as part of the explanation of the nature of reflection.

Chemical approaches to penicillin allergy—V. Nature of reaction between rabbit antigen (CRP-penicillin conjugate) and rabbit antipenicillin antibody

The availability of an electrophoretically homogeneous rabbit penicillin carrier receptor protein (CRP) and rabbit antipenicillin antibody afforded an idealin vitro system to calculate the thermodynamic parameters of the binding of14C benzyl penicillin CRP conjugate (antigen) to the purified rabbit antipenicillin antibody. The thermodynamic parameters of this antigen-antibody reaction has been studied by radio-active assay method by using millipore filter. Equilibrium constant (K) of this reaction has been found to be 2·853×109M−2 and corresponding free energy (ΔG) at 4°C and 37°C has been calculated to be −12·02 and −13·5 kcal/mole, enthalpy (ΔH) and entropy (ΔS) has been found to be 361 kcal/mole and +30 eu/mole respectively. Competitive binding studies of CRP-analogue conjugates with the divalent rabbit antibody has been carried out in the presence of14C-penicilloyl CRP. It was found that 7-deoxy penicillin-CRP complex and 6-amino penicilloyl CRP conjugate binds to the antibody with energies stronger than that with the14C-penicilloyl CRP. All the other analogue conjugates are much weaker in interfering with the binding of the penicilloyl CRP with the antibody. The conjugate of methicillin,o-nitro benzyl penicillin and ticarcillin with CRP do not materially interfere in the process.

Chicken prealbumin: Nature of its heterogeneity and binding of plasma retinol-binding protein and thyroid hormones

The heterogeneity of chicken prealbumin (PA) has been shown to be due to the occurrence of three different plasma proteins (PA1 PA2 and PA3). Equilibrium dialysis studies revealed that the thyroid hormones bind specifically to PA2. These hormones bind at the same site on PA2. Circular dichroism studies failed to reveal conformational changes on interaction of retinol-binding protein and thyroid hormone with PA2. Both retinol-binding protein and thyroid hormone are independently transported by PA2.

The nature of dislocation motion in quasicrystals

Calculations in a hydrodynamic model of quasicrystal dynamics show that dislocation motion in these systems is impeded by a drag far greater than that in crystals.

Investigations of the Nature of Critical Line Very Close to a Double Critical Point

The curvature of the line of critical points in a reentrant ternary mixture is determined by approaching the double critical point (DCP) extremely closely. The results establish the continuous and quadratic nature of this line. Out study encompasses as small a loop size (ΔT) as 663 mK. The DCP is realized when ΔT becomes zero.

Nature of nitrogen adsorbed on transition metal surfaces as revealed by electron spectroscopy and cognate techniques

The nature of the chemisorbed states of nitrogen on various transition metal surfaces is discussed comprehensively on the basis of the results of electron spectroscopic investigations augmented by those from other techniques such as LEED and thermal desorption. A brief discussion of the photoemission spectra of free N2, a comparison of adsorbed N2 and CO as well as of physisorption of N2 on metal surfaces is also presented. We discuss the chemisorption of N2 on the surfaces of certain metals (e.g. Ni, Fe, Ru and W) in some detail, paying considerable attention to the effect of electropositive and electronegative surface modifiers. Features of the various chemisorbed states (one or more weakly chemisorbed gamma-states, strongly chemisorbed alpha-states with bond orders between 1 and 2. and dissociative chemisorbed beta-states) on different surfaces are described and relations between them indicated. While the gamma-state could be a precursor of the alpha-state, the alpha-state could be the precursor of the beta-state and this kind of information is of direct relevance to ammonia synthesis. The nature of adsorption of N2 on the surfaces of some metals (e.g. Cr, Co) deserves further study and such investigations might as well suggest alternative catalysts for ammonia synthesis.