Practical syntheses of [1,3,5]‐triazine dendritic molecules on solid supports

A practical and divergent synthesis of supported [1,3,5]‐triazine dendritic molecules on Wang resin, PEGA resin, SynPhase? Lanterns, and silica gel is described. The alkylamine linkers used allow derivatization with functionality for both synthetic (e.g., supported reagent and scavenger activity) and chemical biology applications. The use of supported intermediates allows differentiation of symmetric linkers without the need for protecting group chemistry. The synthetic route uses inexpensive, readily available starting materials in a straightforward and scaleable strategy. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2248–2259, 2006     

Di-jet shape modification in heavy ion collisions

We present preliminary results from intermediate p _T(1–5 GeV/c) di-hadron azimuthal correlations induced by hadronic di-jets produced in AuAu collisions at √s _NN =200 GeV. The near-side (Δ?～0) has a typical singlepeaked structure which broadens with the centrality of the collision. A qualitatively new phenomenon shows up in the shape of the away-side (Δ?～π): it has a symmetric, double-peaked structure in central and mid-central collisions.     

When maths really is rocket science

Two problems in projectiles are discussed which generate interestingloci.     

Determination of phosphorus in steels by radiochemical neutron activation analysis

The viability of radiochemical neutron activation analysis as a method for certification of phosphorus in steels was tested by analysis of SRM low alloy steels. Preliminary results are generally in agreement with certified values. The limit of detection, as defined by Currie¹, was determined to be 5 μg/kg.     

On conservative approximation by linear polynomial operators an extension of the Bernstein's operator

In this work we study linear polynomial operators preserving some consecutive i-convexities and leaving invariant the polynomials up to a certain degree. First, we study the existence of an incom patibility between the conservation of certain i-convexities and the invariance of a space of polynomials. Interpolation properties are obtained and a theorem by Berens and DeVore about the Bernstein's operator is extended. Finally, from these results a generalized Bernstein's operator is obtained. This work was supported by Junta de Andalucia. Grupo de investigación: Matemática Aplicada. Código: 1107     

Morphologies of microporous polyethylene and polypropylene crystallized from solution in supercritical propane

The morphologies of solvent-free, microporous, mechanically self-supporting cylinders of linear polyethylene and isotactic polypropylene, crystallized from solution in supercritical propane, were examined by an SEM technique. The morphology of gels (or foams), obtained with little or no shrinkage from 2% to 35% solutions by weight of polyethylene (99% to 85% porosities), is shown in some detail. Lamellae with very little or considerable mutual organization occur, often in the form of stacks with straight or coiled axes (axialites). Further growth of these can lead to particles with a roughly spherical overall shape and a predominantly radial orientation of the lamellae at the particle surface. Subcooled isotactic polypropylene, on the other hand, crystallizes in the form of perfectly shaped birefringent microspheres of very uniform size. ©1995 John Wiley & Sons, Inc.     

The decay of theZ boson into four massive fermions

We calculate, the partial width for the tree level decay of theZ boson into four massive fermions atO(α²) and \(O(\alpha _s^2 )\) . Analytic expressions for the helicity amplitudes are presented. We also present ‘observable’ widths for the case when the fermions are energetic and well separated, and make a comparison between the massive and massless matrix elements in this region. We make a direct comparison between the four fermion decay and the production and decay of the Higgs boson via the Bjorken mechanism, \(Z \to H\mu ^ + \mu ^ - \to q\bar q\mu ^ + \mu ^ - \) . Provided the detector resolution is good, \(\Delta m_{q\bar q} \) ～ few GeV, the Higgs signal stands clearly above the four fermion background for all Higgs boson masses considered.