Вероятностно-детерминированная модель расчета безопасного расстояния при разливе топлива

В статье рассматриваются основные опасные факторы при эксплуатации автозаправочных станций, опасные факторы топливных жидкостей, их физические и физико-химические свойства. Основная задача в статье - проанализировать все возможные риски, возникающие при эксплуатации АЗС, выявить наиболее вероятные неблагоприятные события, способные привести к повреждениям и разрушениям АЗС. Проанализировать возможные сценарии развития аварии для выявления наиболее опасного. Данные исследования позволят в дальнейшем использовать математическую модель для определения радиуса поражения зданий, сооружений и населения, и определения безопасного расстояния для опасных объектов - АЗС.The article deals with the main hazards during the operation of gasoline stations, the dangerous factors of fuel fluids, their physical and physicochemical properties. The main task in the article is to analyze all possible risks arising from the operation of the filling station, to identify the most likely adverse events that can lead to damage and destruction of the filling stations. Analyze possible scenarios for the development of an accident to identify the most dangerous. The given researches will allow to use in the further mathematical model for definition of radius of destruction of buildings, constructions and the population, and definition of a safe distance for dangerous objects - the gas station

High throughput <i>in situ</i> EXAFS instrumentation for the automatic characterization of materials and catalysts

An XAS data acquisition and control system for the in situ analysis of dynamic materials libraries under control of temperature and gaseous environment has been developed. It was integrated at the SRS in Daresbury, UK, beamline 9.3, using a Si (220) monochromator and a 13 element solid state Ge fluorescence detector. The core of the system is an intelligent X, Y, Z, θ positioning system coupled to multi-stream quadrupole mass spectrometry analysis (QMS). The system is modular and can be adapted to other synchrotron radiation beamlines. The entire software control was implemented using Labview and allows the scan of a variety of library sizes, in several positions, angles, gas compositions and temperatures with minimal operator intervention. The system was used for the automated characterization of a library of 91 catalyst precursors containing ternary combinations of Cu, Pt, and Au on γ-Al2O3, and for the evaluation and structural characterization of eight Au catalysts supported on A12O3 and TiO2. Mass spectrometer traces reveal conversion rate oscillations in 6wt % Au/γAl2O3 catalysts. The use of HT experimentation for in situ EXAFS studies demonstrates the feasibility and potential of HT in situ XAFS for synchrotron radiation studies

Microreactor cells for high throughput x-ray absorption spectroscopy

High-throughput experimentation has been applied to X-ray Absorption spectroscopy as a novel route for increasing research productivity in the catalysis community. Suitable instrumentation has been developed for the rapid determination of the local structure in the metal component of precursors for supported catalysts. An automated analytical workflow was implemented that is much faster than traditional individual spectrum analysis. It allows the generation of structural data in quasi-real time. We describe initial results obtained from the automated high throughput (HT) data reduction and analysis of a sample library implemented through the 96 well-plate industrial standard. The results show that a fully automated HT-XAS technology based on existing industry standards is feasible and useful for the rapid elucidation of geometric and electronic structure of materials

High Throughput In Situ XAFS Screening of Catalysts

We outline and demonstrate the feasibility of high-throughput (HT) in situ XAFS for synchrotron radiation studies. An XAS data acquisition and control system for the analysis of dynamic materials libraries under control of temperature and gaseous environments has been developed. The system is compatible with the 96-well industry standard and coupled to multi-stream quadrupole mass spectrometry (QMS) analysis of reactor effluents. An automated analytical workflow generates data quickly compared to traditional individual spectrum acquisition and analyses them in quasi-real time using an HT data analysis tool based on IFFEFIT. The system was used for the automated characterization of a library of 91 catalyst precursors containing ternary combinations of Cu, Pt, and Au on ?-Al2O3, and for the in situ characterization of Au catalysts supported on Al2O3 and TiO2

Untersuchung anodischer Oxidationsschichten an Gold

Titlepage Contents List of Tables XI List of Figures XIII 1 Introduction 3 2 Experimental 9 3 Results 45 4 Discussion 93 5 Summary 105 Bibliography 109 Appendix 115In this thesis, the growth and decomposition of electrochemically formed gold oxide has been characterised. The results obtained were related to the ones known from literature as well as to results of differently prepared gold oxide samples. The most important points can be summarised as follows: Electrochemically prepared gold oxide has a highly amorphous structure which shows no significant long range order. Therefore, no XRD data on this substance is available. The EXAFS is much more featureless than that of crystalline gold oxide which has also been analysed in this thesis. During the growth process - which has been monitored over a large range of oxidation currents - no intermediate species could be detected using EXAFS and XANES spectroscopy. The growth constants found by applying pure electrochemical methods and XANES spectroscopy are in line with each other. Thermal desorption spectroscopy yields one desorption state with an activation energy of 133 kJ/mol. In contrast to this, TPD spectra from oxygen sputtered samples show up to four distinguishable features, which are in line with other results from our group. XPS analysis suggests the presence of three different oxygen 1s and two different gold 4f lines in the oxidation of polycrystalline gold. Sputtered samples show two oxygen and up to two gold 4f peaks. The spectra obtained here are similar to the ones known in the literature although the interpretation esp. in the O 1s region is different from some authors. Furthermore, the use of theoretical fitting standards for phase composition analysis using the FEFFIT algorithm has been demonstrated. In this case, reference compounds were available so that the theoretical results could be compared with the results from linear combination methods. The use of this method lies in the analysis of e.g. catalytic material with no known structure, where reference paths can be created with nearly any geometry using the FEFF8 algorithm. The results in this work serve as reference for catalytic measurements to clarify whether oxidic gold species play a role during CO oxidation or not.In dieser Arbeit wurde die elektrochemische Bildung sowie die thermische Zersetzung von Goldoxid untersucht. Die gewonnenen Ergebnisse wurden in den Literaturkontext eingeordnet sowie mit Resultaten von Studien zu kommerziell erhältlichem und kristallinem Oxid verglichen. Die wichtigsten Ergebnisse können wie folgt zusammengefaßt werden: Elektrochemisch erzeugtes Gold(III)oxid zeigt eine stark amorphe Struktur mit keiner signifikanten Fernordnung (XRD-amorph, EXAFS zeigt im Wesentlichen eine Koordinationsschale). Damit steht dieses Material im Gegensatz zu dem kristallinen Analogon, welches in dieser Arbeit ebenfalls analysiert wurde und einen signifikant höheren Ordnungsgrad besitzt. Verglichen mit kommerziellem Oxid zeigt die EXAFS Analyse eine starke Ähnlichkeit dieser Materialien. Während des Wachstumsprozesses ließen sich keinerlei intermediäre Gold- Sauerstoffphasen detektieren. Der Zustand der oxidierten Oberfläche ließ sich jederzeit durch eine Mischung aus (hydratisiertem) Oxid und Gold erklären. Die Wachstumskonstanten, welche durch elektrochemische Methoden sowie XAS bestimmt wurden zeigen eine gute Übereinstimmung. TPD Messungen zeigen ab einem Oxidationspotential von +1.6 V gegen SCE einen Zustand, welcher 1. Ordnung ist und eine Desorptionsenergie von 133 kJ/mol besitzt. Die XPS Analyse zeigt im Falle der elektrochemischen Oxidation drei verschiedene Sauerstoff und zwei Gold 4f Zustände. Die Spektren lassen sich mit denen aus der Literatur vergleichen, obwohl die Interpretation voneinander abweicht. Desweiteren wurde der Nutzen von theoretisch berechneten Referenzpfaden für die EXAFS Analyse mittels des FEFF8 Algorithmus gezeigt. In dieser Arbeit wurde die Phasenzusammensetzung einer Oxidprobe auf zwei Arten bestimmt. Es konnte gezeigt werden, daß die Nutzung von theoretisch berechneten Referenzkomponenten die gleichen Resultate wie andere Methoden liefert. Dieses Faktum ist besonders für industrielle Proben wie z.B. Katalysatoren interessant, da dort oftmals Stoffe auftreten können, die ausserhalb des katalytischen Mechanismus nicht existent sind