Das Vakuumschulen‐Zertifikat

Certification of Vacuum Trainings This article describes the certification process for quality assurance of vacuum trainings by the German Vacuum Society (DVG). This quality certification was established in 2014. The first certification has been completed, another is ongoing. The certification ensures all participants a certain level of teaching and learning content in both theoretical and practical parts of the trainings. The applicants are assessed by a team of auditors named by the DVG. The procedure also includes discussion about possible improvements. The spectrum of training courses that can be certified covers general vacuum trainings and special training like leak detection, coating technologies, or mass spectrometry. For further information please contact Dr. Michael Wahl, Tel. +49 631 205‐73‐3333, E‐Mail wahl@ifo.uni‐kl.de     

Adsorption of the Inhalation Anesthetic Isoflurane from Dry and Humid Atmosphere

For environmental and occupational safety reasons, the inhalation anesthetic isoflurane must be removed from indoor air in hospitals. The present work investigated experimentally the coadsorption of isoflurane and water on four different commercial adsorbents: two activated carbons and two zeolites. Adsorption isotherms from dry and humid atmosphere are shown and discussed, i.e., mixture data are compared with those of the pure substances. For all four adsorbents the dominant parameter regarding structural properties is the pore size distribution. In the case of the zeolites, the surface chemistry, especially the aluminum content, plays a role, too.     

Systematic Assessment of Fragment Identification for Multitarget Drug Design

Designed multitarget ligands are a popular approach to generating efficient and safe drugs, and fragment-based strategies have been postulated as a versatile avenue to discover multitarget ligand leads. To systematically probe the potential of fragment-based multiple ligand discovery, we have employed a large fragment library for comprehensive screening on five targets chosen from proteins for which multitarget ligands have been successfully developed previously (soluble epoxide hydrolase, leukotriene A4 hydrolase, 5-lipoxygenase, retinoid X receptor, farnesoid X receptor). Differential scanning fluorimetry served as primary screening method before fragments hitting at least two targets were validated in orthogonal assays. Thereby, we obtained valuable fragment leads with dual-target engagement for six out of ten target combinations. Our results demonstrate the applicability of fragment-based approaches to identify starting points for polypharmacological compound development with certain limitations.     

Development of superconducting absorbers for CRESST light detectors

An important aspect of dark matter search experiments is the active background reduction by identification of the type of particle interacting in the detector. In CRESST this is achieved by a simultaneous detection of heat and light produced by an interaction in a scintillating crystal. The overall light collection efficiency is a crucial parameter in order to achieve enough sensitivity to measure the small fraction of the deposited energy that is emitted as scintillation light. For this purpose, a thin superconducting lead film deposited on sapphire substrates has been tested as an alternative light absorber to a silicon absorber. The first results already show a better light absorption of the lead film. Other superconducting films are also being analyzed.     

Experimental study of gas-dynamically induced nanoparticle synthesis by use of adapted sampling probes

A new process for the synthesis of nanoparticles in the gas-phase is experimentally investigated. The gas-dynamically induced nanoparticle synthesis uses the initiation of the chemical reaction by gasdynamic shock and the quenching of high temperature gas by accelerating the flow from subsonic flow speed to supersonic speed. Therefore, the design of the reactor consists of two Laval nozzles. The process provides high heating and cooling rates, an adjustable reaction time and a particle synthesis at constant thermodynamic conditions to obtain non-aggregated nanoparticles. In order to analyze the synthesized SiO₂ particles during their growth, samples are taken in the reaction volume and downstream of the quenching. The particles from the reaction chamber were extracted with the help of a specially designed water-cooled probe. The geometry of the probe is optimized by CFD simulations. The particles downstream the quenching are extracted by a heated and isolated probe. The particles are collected on TEM grids. The experimental investigations show that the synthesized particles are spherical and non-aggregated in the reaction chamber and after quenching. The possibility to synthesize a non-aggregated product in the novel process is thus demonstrated. The mean particle size is defined by the process conditions and varies from 25 to 37 nm after quenching.