A kinetics study of the homogeneous and heterogeneous components of the HCl + ClONO_2 reaction

The kinetics of the reaction HCl + ClONO_2 → Cl_2 + HNO_3 were investigated at 298 K using a flow reactor with FTIR analysis to assess the importance of this reaction for stratospheric chemistry. The observed reaction was characteristic of a heterogeneous process; an upper limit of 5 × 10^(−18) cm³ molecule^(−1) s^(−1) was obtained for the homogeneous gas phase rate constant. From calculations of the first order wall rate constant, estimates were made of the reaction rate on stratospheric aerosols. Because both HCl and ClONO_2 need to be adsorbed on the particle surface, the reaction will be of negligible importance under most stratospheric conditions

Archiving Software Surrogates on the Web for Future Reference

Software has long been established as an essential aspect of the scientific process in mathematics and other disciplines. However, reliably referencing software in scientific publications is still challenging for various reasons. A crucial factor is that software dynamics with temporal versions or states are difficult to capture over time. We propose to archive and reference surrogates instead, which can be found on the Web and reflect the actual software to a remarkable extent. Our study shows that about a half of the webpages of software are already archived with almost all of them including some kind of documentation.Comment: TPDL 2016, Hannover, German

Dimensionality effects in restricted bosonic and fermionic systems

The phenomenon of Bose-like condensation, the continuous change of the dimensionality of the particle distribution as a consequence of freezing out of one or more degrees of freedom in the low particle density limit, is investigated theoretically in the case of closed systems of massive bosons and fermions, described by general single-particle hamiltonians. This phenomenon is similar for both types of particles and, for some energy spectra, exhibits features specific to multiple-step Bose-Einstein condensation, for instance the appearance of maxima in the specific heat. In the case of fermions, as the particle density increases, another phenomenon is also observed. For certain types of single particle hamiltonians, the specific heat is approaching asymptotically a divergent behavior at zero temperature, as the Fermi energy $\epsilon_{\rm F}$ is converging towards any value from an infinite discrete set of energies: ${\epsilon_i}_{i\ge 1}$. If $\epsilon_{\rm F}=\epsilon_i$, for any i, the specific heat is divergent at T=0 just in infinite systems, whereas for any finite system the specific heat approaches zero at low enough temperatures. The results are particularized for particles trapped inside parallelepipedic boxes and harmonic potentials. PACS numbers: 05.30.Ch, 64.90.+b, 05.30.Fk, 05.30.JpComment: 7 pages, 3 figures (included

Bose-Einstein condensation as symmetry breaking in compact curved spacetimes

We examine Bose-Einstein condensation as a form of symmetry breaking in the specific model of the Einstein static universe. We show that symmetry breaking never occursin the sense that the chemical potential $\mu$ never reaches its critical value.This leads us to some statements about spaces of finite volume in general. In an appendix we clarify the relationship between the standard statistical mechanical approaches and the field theory method using zeta functions.Comment: Revtex, 25 pages, 3 figures, uses EPSF.sty. To be published in Phys. Rev.

ISPIDER Central: an integrated database web-server for proteomics

Despite the growing volumes of proteomic data, integration of the underlying results remains problematic owing to differences in formats, data captured, protein accessions and services available from the individual repositories. To address this, we present the ISPIDER Central Proteomic Database search (http://www.ispider.manchester.ac.uk/cgi-bin/ProteomicSearch.pl), an integration service offering novel search capabilities over leading, mature, proteomic repositories including PRoteomics IDEntifications database (PRIDE), PepSeeker, PeptideAtlas and the Global Proteome Machine. It enables users to search for proteins and peptides that have been characterised in mass spectrometry-based proteomics experiments from different groups, stored in different databases, and view the collated results with specialist viewers/clients. In order to overcome limitations imposed by the great variability in protein accessions used by individual laboratories, the European Bioinformatics Institute's Protein Identifier Cross-Reference (PICR) service is used to resolve accessions from different sequence repositories. Custom-built clients allow users to view peptide/protein identifications in different contexts from multiple experiments and repositories, as well as integration with the Dasty2 client supporting any annotations available from Distributed Annotation System servers. Further information on the protein hits may also be added via external web services able to take a protein as input. This web server offers the first truly integrated access to proteomics repositories and provides a unique service to biologists interested in mass spectrometry-based proteomics

A dynamic logic for every season

This paper introduces a method to build dynamic logics with a graded semantics. The construction is parametrized by a structure to support both the spaces of truth and of the domain of computations. Possible instantiations of the method range from classical assertional) dynamic logic to less common graded logics suitable to deal with programs whose transitional semantics exhibits fuzzy or weighted behaviour.This leads to the systematic derivation of program logics tailored to specific program classes

A kinetics study of the homogeneous and heterogeneous components of the HCl + ClONO_2 reaction

The kinetics of the reaction HCl + ClONO_2 → Cl_2 + HNO_3 were investigated at 298 K using a flow reactor with FTIR analysis to assess the importance of this reaction for stratospheric chemistry. The observed reaction was characteristic of a heterogeneous process; an upper limit of 5 × 10^(−18) cm³ molecule^(−1) s^(−1) was obtained for the homogeneous gas phase rate constant. From calculations of the first order wall rate constant, estimates were made of the reaction rate on stratospheric aerosols. Because both HCl and ClONO_2 need to be adsorbed on the particle surface, the reaction will be of negligible importance under most stratospheric conditions