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The mid-infrared spectra of mixtures of ethene and carbon dioxide dissolved in liquid argon have been investigated between 88 and 123 K. At higher concentrations of ethene, evidence was found for the formation of a 1:1 complex in which the carbon atom of the CO2 moiety binds to the C&z.dbnd6;C double bond. By recording spectra at different temperatures, the complexation enthalpy for the 1:1 complex was determined to be -4.9(1) kJ mol-1. Using Free Energy Perturbation Monte Carlo simulations to correct for solvent influences and statistical thermodynamics to account for zero-point vibrational and thermal influences, the complexation enthalpy was transformed into a vapor phase complexation energy. The resulting value, -6.8(8) kJ mol-1, is compared with theoretical data obtained from ab initio calculations in which the equilibrium geometry of the complex is calculated using BSSE-corrected gradient techniques. [Copyright &y& Elsevier]

Investigates the use of cryosolutions infrared in determining the complexes of haloforms with dimethyl ether. Influence of the ether on the haloform carbon (C)-hydrogen (H) stretching; Reaction mechanism of C-H bonds with electrons of oxygen and nitrogen atoms; Complexation shift of the haloform C-H stretching.

Purpose: This paper aims to describe the development of a knowledge management system (KMS) for the Nadir and Occultation for Mars Discovery (NOMAD) instrument on board the ESA/Roscosmos 2016 ExoMars Trace Gas Orbiter (TGO) spacecraft. The KMS collects knowledge acquired during the engineering process that involved over 30 project partners. In addition to the documentation and technical data (explicit knowledge), a dedicated effort was made to collect the gained experience (tacit knowledge) that is crucial for the operational phase of the TGO mission and also for future projects. The system is now in service and provides valuable information for the scientists and engineers working with NOMAD. Design/methodology/approach: The NOMAD KMS was built around six areas: official documentation, technical specifications and test results, lessons learned, management data (proposals, deliverables, progress reports and minutes of meetings), picture files and movie files. Today, the KMS contains 110 GB of data spread over 11,000 documents and more than 13,000 media files. A computer-aided design (CAD) library contains a model of the full instrument as well as exported sub-parts in different formats. A context search engine for both documents and media files was implemented. Findings: The conceived KMS design is basic, flexible and very robust. It can be adapted to future projects of a similar size. Practical implications: The paper provides practical guidelines on how to retain the knowledge from a larger aerospace project. The KMS tool presented here works offline, requires no maintenance and conforms to data protection standards. Originality/value: This paper shows how knowledge management requirements for space missions can be fulfilled. The paper demonstrates how to transform the large collection of project data into a useful tool and how to address usability aspects. [ABSTRACT FROM AUTHOR]