Immobilizing redox enzymes at mesoporous and nanostructured electrodes

Three key challenges are stimulating intensive research in the development of productive direct electron transfer mode enzyme electrodes: proper enzyme orientation, high enzyme loading, and full retention of enzyme activity. In this review, we summarize some significant advances that have been reported in the last years on the design of mesoporous and nanostructured electrodes as enzyme scaffolds and of innovative methodologies for wiring enzymes to electrodes. Particular attention is given to investigations on physical factors that determine a favorable enzyme immobilization, to provide rational guidelines for the design of productive enzymatic electrodes. Finally, some emerging trends focused on the spatial organization of either single enzymes or enzyme cascades are also briefly addressed.     

Geometry of an Accelerated Rotating Disk

We analyze the geometry of a rotating disk with a tangential acceleration in the framework of the theory of Special Relativity, using the kinematic linear differential system that verifies the relative position vector of time-like curves in a Fermi reference. A numerical integration of these equations for a generic initial value problem is made up and the results are compared with those obtained in other works.     

Electrochemical reduction of monothiobenzils in the presence of aroyl chlorides. First synthesis of (Z)-α-benzoyloxy-β-benzoylthiostilbenes

The first method for the synthesis of the title compounds has been established involving a stereoselective electrochemical diacylation process. The cathodic reductions of monothiobenzils in an aprotic medium, under constant potential, in the presence of twofold molecular amounts of aroyl chlorides provide previously unknown (Z)-α-benzoyloxy-β-benzoythiostilbenes in high to quantitative yields.     

Inclusive (γ, N), (γ, NN) and (γ, Nπ) reactions in nuclei at intermediate energies

Differential cross sections of nucleons excited in photonuclear reactions in medium and heavy nuclei are studied by considering all relevant reaction mechanisms leading to the excitation of protons or neutrons. We take advantage of previous microscopic studies for the absorption and scattering of photons and photoproduced pions, and implement a simulation code in order to take into account the propagation of the nucleons as well as their collisions with other nucleons in the nuclear medium, which generate secondary excited nucleons. Comparison with experimental data is done. Cross sections for nucleon emission in coincidence with one pion are also calculated, and some coincidence observables are discussed.     

Synthesis and thermal crosslinking of oxazolidine‐functionalized polyurethanes

A new oxazolidine derivative was obtained from phenol, 2‐amino‐2‐methylpropane‐1,3‐diol and paraformaldehyde. The reaction of this novel oxazolidine diol with phenylisocyanate lead to a urethane model compound which can be polymerized thermally by oxazolidine ring opening to give a Mannich bridge structure. Linear segmented polyurethanes were prepared by reaction of different ratios of oxazolidine diol and commercial polyethylenglycol (M_w ～ 400) with 4,4′‐methylenbis (cyclohexylisocyanate) (HMDI, 90% isomers mixture). The polyurethanes were thermally characterized and crosslinked by oxazolidine ring opening to obtain materials which showed improved thermal stability. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4965–4973, 2007