Filtern
Erscheinungsjahr
Dokumenttyp
- Posterpräsentation (11)
- Zeitschriftenartikel (6)
- Vortrag (5)
- Beitrag zu einem Tagungsband (4)
Schlagworte
- Polymorphism (4)
- Crystallization (2)
- Detektion (2)
- Furniture (2)
- Nifedipine (2)
- Raman spectroscopy (2)
- Brand (1)
- Branddetektion (1)
- Brandschutz (1)
- Burning behaviour (1)
Organisationseinheit der BAM
Eingeladener Vortrag
- nein (5)
The crystallization of a highly polymorphic compound was studied in situ by combined time-resolved X-ray diffraction and Raman spectroscopy. Any influences of solid surfaces, temperature, and humidity on the crystallization were omitted by the use of a specially designed acoustic levitator. Investigations of polymorphic phase transitions during the crystallization process in different solvents allowed a structure assignment from first crystalline assemblies to final crystalline form. For the first time, it was possible to yield pure phases of selected polymorphs of the model compound ROY (5-methyl-2-[(2-nitrophenyl)amino]-3-thiophenecarbonitrile) directly from solution. The influence of the solvent on the final products and transient phases during the crystallization process was elucidated.
About 80 % of all fire fatalities in Germany occur in fires in homes1. UK statistics show that living and bed room fires are more often responsible for fatalities than kitchen fires although kitchen fires occur much more often2. It has been known for some time that modern materials tend to burn differently from older materials and it has been acknowledged that the amount of combustible plastics in homes has increased significantly over the last decades3-7. To investigate the influence of modern furniture and ventilation conditions of fires in homes a series of four large scale tests in two living rooms with adjacent rooms was performed by BAM and the Frankfurt fire service8. Two living rooms, one with older furniture and one with modern furniture were tested twice each. Each test started with the ignition of a paper cushion on an upholstered chair. The influence of modern materials on the fire development was investigated as well as the influence of the ventilation on the fire development. Two tests with closed windows and two tests with open windows were performed. Temperatures were measured in the living rooms and the adjacent rooms, gas compositions were measured in the adjacent rooms and videos were taken in all rooms. The ventilation as well as the different materials influenced the fire development regarding temperatures in the rooms and smoke production and composition significantly. The fire in the living room with modern furniture developed faster than the same setting with older furniture. More ventilation (open window) led to higher temperatures in the rooms and faster fire development as well. Smoke gas composition was measured in the adjacent rooms to assess the positive effect for a person being in the adjacent room and not in the room of fire origin. In all settings an upholstered chair was the first burning item. The modern upholstered chair was investigated in three pre-experiments under different conditions to enhance the understanding of the living room fires. The measured mass losses and derived mass loss rates have been used for numerical modelling of the pre-experiments.
Bei einzelnen Objekten, die unter Laborbedingungen verbrennen, konnte schon seit längerer Zeit ein großer Unterschied zwischen älteren und neuen Möbeln hinsichtlich der Entflammbarkeit und der Rauchentwicklung sowie der Rauchgaszusammensetzung festgestellt werden [1, 2]. In einer Serie von Großversuchen im Rahmen des vom BMBF geförderten Forschungsvorhabens TIBRO wurde in Zusammenarbeit mit der Feuerwehr Frankfurt in vier Großversuchen die Brand- und Rauchentwicklung in einem Wohnzimmer und einem angrenzenden Zimmer untersucht. Es wurden ältere Möbel und moderne Möbel sowie unterschiedliche Belüftungsbedingungen untersucht. Alle vier Brände gingen von einem Sessel aus, der mit einem Papierkissen entzündet wurde. Es wurden jeweils im Brandraum und im Nachbarraum Temperaturen gemessen sowie die zeitlich veränderliche Rauchgaszusammensetzung in zwei unterschiedlichen Raumhöhen in der Zimmermitte des Nachbarraums bestimmt [3].
Der Einfluss der in der Wohnung vorhandenen Materialien sowie der Einfluss der Belüftung auf die Brandentwicklung wurden untersucht. Sowohl die Art der Materialien als auch die Belüftung beeinflussen die Brandentwicklung signifikant. Statistiken und die Erfahrung der Feuerwehren zeigen, dass für Personen, die sich im Brandentstehungsraum befinden, die Hilfe der Feuerwehr in den meisten Fällen zu spät kommt. Für den Nachbarraum können anhand der Großversuche Abschätzungen über den Zeitgewinn für Personen, die sich dort befinden, abgeleitet werden.