Glueball plus pion production in hard exclusive two-photon processes

We here compute the reaction G⁰ for various glueball candidatesG and their assumed quantum states, using a non-relativistic gluon bound-state model for the glueball.     

Free differential algebras: Their use in field theory and dual formulation

The gauging of free differential algebras (FDA's) produces gauge field theories containing antisymmetric tensors. The FDA's extend the Cartan-Maurer equations of ordinary Lie algebras by incorporating p-form potentials (p>1). We study here the algebra of FDA transformations. To every p-form in the FDA, we associate an extended Lie derivative l generating a corresponding gauge transformation. The field theory based on the FDA is invariant under these new transformations. This gives geometrical meaning to the antisymmetric tensors. The algebra of Lie derivatives is shown to close and provides the dual formulation of FDA's.     

Anodic behaviour of mono- and bisdithiafulvenyl-9,9′-spirobifluorene: insertion of vinylogous TTF into the spirobifluorenyle framework

New three-dimensional copolymers containing 9,9′-spirobifluorenyl-ethylene units were prepared by anodic oxidation of 9,9′-spirobifluorenes 2-mono- or 2,7′-disubstituted by a dithiafulvenyl unit. The synthesis, physicochemical properties and electrochemistry of both monomers and derived oligomers and polymers are reported.     

Global optimization and stochastic differential equations

Let ⁿ be then-dimensional real Euclidean space,x=(x ₁,x ₂, ...,x _n)^{T n} , and letf: ⁿ R be a real-valued function. We consider the problem of finding the global minimizers off. A new method to compute numerically the global minimizers by following the paths of a system of stochastic differential equations is proposed. This method is motivated by quantum mechanics. Some numerical experience on a set of test problems is presented. The method compares favorably with other existing methods for global optimization.This research has been supported by the European Research Office of the US Army under Contract No. DAJA-37-81-C-0740.The third author gratefully acknowledges Prof. A. Rinnooy Kan for bringing to his attention Ref. 4.     

Effects of simple model solutes on water dynamics: residence time analysis

The water residence time around pairs of simple hydrophilic and hydrophobic solutes, kept immobilized to model groups on slowly diffusing macromolecules, has been investigated along 400 ps molecular dynamics simulations. Results show that the water mobility around one solute strongly depends on the polarity characteristics of the other solute of the pair.     

2020 Roadmap on two-dimensional nanomaterials for environmental catalysis

This roadmap demonstrates a series of two-dimensional nanomaterials, such as graphene, black phosphorus, oxides, layered double hydroxides, chalcogenides, bismuth-based layered compounds, MXenes, metal organic frameworks, covalent organic frameworks, and others, for environmental catalysis.     

Gas-phase chemistry of the negative ions of fully-protected peptides by high-resolution electrospray ionization tandem mass spectrometry

Fully-protected C-terminal free peptides can be conveniently analyzed by high-resolution electrospray tandem mass spectrometry (ESI-MS/MS) in a quadrupole quadrupole time-of-flight tandem hybrid mass spectrometer, operated in the negative (-) ionizaionization mode. The unusual choice of negative ions in mass spectrometry applications to peptide analysis was needed to obtain exhaustive sequence and structural data. The low-energy collision-induced dissociation (CID) experiments provided, in fact, tandem mass spectra displaying highly diagnostic fragments with a good signal-to-noise ratio. The method is applied to segments of porcine calcitonin (Cal), Cal (1016, 1), Cal (1724, 2) and Cal (2528, 3) whose [M H]- deprotonated molecular ions provided low-energy CID mass spectra which allow the evaluation either of the primary structure of the peptide and of the location of the side-chain protective groups. ESI (+) MS can be conveniently used, in the high resolution mode, to achieve precise information on the elemental composition of the examined peptides.     

Approximation in Hardy spaces

Summary We prove direct and converse theorems of approximation for distributions in the Hardy spaces H^p, 0相似文献   

Field-theoretic approach to second-order phase transitions in two- and three-dimensional systems

We review the physical principles which are at the basis of recent field-theoretic computations of the critical exponents in two- and three-dimensional systems. We concentrate on those points that do not show up explicitly in the more standard-expansion: they must be discussed with care if one uses a perturbative approach at fixed space dimensions (the loop expansion). We present in detail simple computations of the critical exponents, while we summarize the results of longer and more accurate computations.