Study of the reactione + e −→K + K − in the energy range1350 \leqq \sqrt s \leqq 2400 MeV

Thee ⁺ e ^?→K ⁺ K ^? cross section has been measured from about 750 events in the energy interval \(1350 \leqq \sqrt s \leqq 2400 MeV\) with the DM2 detector at DCI. TheK ^± form factor |F _F ^±| cannot be explained by the ρ, ω, ? and ρ′(1600). An additional resonant amplitude at 1650 MeV has to be added as suggested by a previous experiment.     

Dominant ion transport processes of ionic liquid electrolyte in poly(3,4-ethylenedioxythiophene)

Electrochemical quartz crystal microgravimetry was used to study movement of the ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMIBTI) into and out of poly(3,4-ethylenedioxythiophene) (PEDOT). In 0.1M EMIBTI/acetonitrile, anionic transport predominates, as is typical of solution-based electrolytes. In pure EMIBTI, on the other hand, the minimal mass change observed during polymer oxidation/reduction was observed to be cation-dominant. PEDOT deposition from dilute EMIBTI solution followed by cycling in neat EMIBTI resulted in rapid decrease of electroactivity. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2013     

Radiative decay ofJ/ψ into γ π+ π−

The radiative decayJ/ψ → γ π⁺ π^? has been studied using the 8.6 millionJ/ψ produced in the DM2 experiment at the DCIe ⁺e^? storage rings at Orsay. The π⁺ π^? mass spectrum shows a cleanf ₂ (1270) signal, and the possible presence of two other states at thef ₂ (1720) andf ₄ (2030) masses. For thef ₂ (1270), the branching ratio BR(J/ψ →γf)xBR(f→π⁺ π^?) is measured to be (7.50±0.30±1.12)×10^?4, and the spin analysis prefers theJ=2 assignment, with helicity parametersx=0.83±0.06 andy=0.01±0.06. The existence of higher mass states is discussed.     

Harmonic tori in De Sitter spaces S^{2n}_1

We show that all superconformal harmonic immersions from genus one surfaces into de Sitter spaces $S^{2n}_{1}$ with globally defined harmonic sequence are of finite-type and hence result merely from solving a pair of ordinary differential equations. As an application, we prove that all Willmore tori in $S^{3}$ without umbilic points can be constructed in this simple way.     

The preparation and properties of highly conductive nonstoichiometric oxide catalysts

Inter-oxide compounds of rare earth and transition metal oxides can be made highly nonstoichiometric by the partial substitution of divalent ions, such as strontium, for the rare earth element. These compounds become highly conductive when suitably treated in oxygen at high temperatures, and have been found to function as efficient oxidation catalysts at low temperatures between 100–300°C. The thermodynamics, transport properties and catalytic behavior for CO and CH₄ oxidation of some systems having the perovskite or the K₂NiF₄ structure are discussed, e.g. La_1−xSr_xMO_3−δ(M=Cr,Mn,Fe,Co,Y) and La_2−xSr_xCuO_4−δ. The catalytic behavior is similar for the Cr,Mn,Fe and Co perovskites, but the solid electrolyte La_0.8Sr_0.2YO_2.9 has no effect in CO oxidation but the greatest activity for CH₄ oxidation.     

Non-planar smoulder propagation governed by diffusion

The steady propagation of a thin smouldering front in a half-spacehas been considered. A suitable coordinate transformation hasallowed the region near the leading edge of the front to beexamined for both a maintained planar surface and with surfacecollapse due to material shrinkage. The change in the oxidizerconcentration for a small increment in the propagation speedfor large time and surface collapse has been determined. Theinfluence of two types of nonlinear diffusion on the shape ofthe smouldering front has been found; other cases can be dealtwith in a similar manner.     

“Bio”‐Macromolecules: Polymer‐Protein Conjugates as Emerging Scaffolds for Therapeutics

Polymer‐protein conjugates are biohybrid macromolecules derived from covalently connecting synthetic polymers with polypeptides. The resulting materials combine the properties of both worlds: chemists can engineer polymers to stabilize proteins, to add functionality, or to enhance activity; whereas biochemists can exploit the specificity and complexity that Nature has bestowed upon its macromolecules. This has led to a wealth of applications, particularly within the realm of biomedicine. Polymer‐protein conjugation has expanded to include scaffolds for drug delivery, tissue engineering, and microbial inhibitors. This feature article reflects upon recent developments in the field and discusses the applications of these hybrids from a biomaterials standpoint.

     

Fractal analysis of size effects and surface morphology effects in catalysis and electrocatalysis

Fractal geometry tools are used in order to analyze several related problems in surface science, catalysis, and electrocatalysis. The effects of complex morphologies of adsorbents, catalysts, and electrodes on various molecular processes with these materials are determined both theoretically and experimentally. It is shown that fractal geometry provides a convenient and natural tool for the elucidation of geometry-performance relations in heterogeneous chemistry. Issues covered are particle size effects in physisorption and chemisorption; morphology effects on a variety of catalytic processes with unsupported catalysts (including coal liquefaction, alkene polymerizations, oxidations, dehydrogenations, and esterifications); surface accessibility effects on molecular interactions in an Eley-Rideal mechanism; surface patterning effects on concentration profiles near the surface; and electrode-morphology effects on a variety of electrochemical and electrocatalytic processes. The domains of applicability of the fractal approach to these problems is discussed.