Reactive hazard associated with chemicals is a major safety issue in process industries. This kind of hazard has caused the occurrence of many accidents, leading to fatalities, injuries, property damage and environment pollution. Reactive hazards can be eliminated or minimized by applying Inherently Safer Design (ISD) principles such as "substitute" or "moderate" strategies. However, ISD would not be a feasible option for industry without an efficient methodology for chemical hazard assessment, which provides the technical basis for applying ISD during process design. In this research, a systematic chemical hazard assessment methodology was developed for assisting the implementation of ISD in the design of inherently safer process. This methodology incorporates the selection of safer chemicals and determination of safer process conditions, which correspond to "substitute" and "moderate" strategies in ISD. The application of this methodology in conjunction with ISD technique can effectively save the time and investment spent on the process design. As part of selecting safer chemicals, prediction models were developed for predicting hazardous properties of reactive chemicals. Also, a hazard index was adopted to rate chemicals according to reactive hazards. By combining the prediction models with the hazard index, this research can provide important information on how to select safer chemicals for the processes, which makes the process chemistry inherently safer. As part of determining safer process conditions, the incompatibility of Methyl Ethyl Ketone Peroxide (MEKPO) with iron oxide was investigated. It was found that iron oxide at low levels has no impact on the reactive hazards of MEKPO as well as the operational safety. However, when iron oxide is beyond 0.3 wt%, it starts to change the kinetics of MEKPO runaway reaction and even the reaction mechanism. As a result, with the presence of a certain level of iron oxide (> 0.3 wt%), iron oxide can intensify the reactive hazards of MEKPO and impose higher risk to process operations. The investigation results can help to determine appropriate materials for fabricating process equipment and safer process conditions.

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Processing facilities are normally designed with sufficient flexibility to handle nominal variations. When the process features planned changes in feedstock and products, scheduling is often used to optimize process operation. The objective of this dissertation is to develop a new approach to design and scheduling with economic, environmental, heat integration and inherently safer design objectives. Specifically, this work introduces a systematic framework and the associated mathematical formulation for simultaneous process design and scheduling while simultaneously addressing economic, environmental, heat integration and inherently safer design objectives. Therefore, more than one type of proper tradeoffs are established between these objectives. The environmental issues pertaining to the parameterized process retrofitting, scheduling, and operation strategies are simultaneously considered along with the environmental impact of these changes. Similarly, the design synthesis of heat-exchange networks (HENs) is addressed in the context of optimizing energy consumption under scheduling scenarios. Finally, the goal of inherently safer design is simultaneously considered with the expected schedules of the process. Several optimization formulations are developed for the projected schedules while allowing design modifications and retrofitting changes. The modifications and changes include new environmental management units, synthesis of flexible and optimal HENs, and design of an inherently safer process. Process models with the appropriate level of relevant details are included in the formulations. A discretization approach has been adopted to allow for a multiperiod optimization formulation over a given time horizon. The resulting framework identifies opportunities for synergism between the economic, environmental, heat integration and inherently safer design objectives. It also determines points of diminishing return beyond which tradeoffs between the above mentioned objectives are established. The devised procedure is illustrated with case studies.

The integration of the safety parameter into process design and optimization is essential. However, there is no previous work in integrating the fire and explosion index (F&EI) into design and optimization. This research proposed a procedure for integrating safety into the design and optimization framework by using the safety parameter as optimization constraint. The method used in this research is Dow’s Fire and Explosion Index which is usually calculated manually. This research automates the calculation of F&EI. The ability to calculate the F&EI, to determine loss control credit factors and business interruption, and to perform process unit risk analysis are unique features of this F&EI program. In addition to F&EI calculation, the F&EI program provides descriptions of each item of the penalties, chemicals/materials databases, the flexibility to submit known chemical/material data to databases, and material factor calculations. Moreover, the sensitivity analyses are automated by generating charts and expressions of F&EI as a function of material inventory and pressure. The expression will be the focal point in the process of integrating F&EI into process design and optimization framework. The proposed procedure of integrating F&EI into process design and optimization framework is verified by applying it into reactor-distillation column system. The final result is the optimum economic and inherently safer design for the reactor and distillation column system.

Flame retardant chemicals were used to make flammable fibres or fabrics flame retardant. Flame retardants protect the flammable material from fire by delaying or preventing the ignition process. The problem with flame retardants is unreliable durability when applied physically or bonded chemically on the surface of the fibre or fabric. This thesis project investigated the implementation of inherently flame retardant fibres as a shield form flame for flammable fibres. The most widely used flammable textiles fibres (cotton and polyester) were mixed with inherently flame retardant fibres (modacrylic and Lenzing FR) pairwise at fibre level for non-woven fabric and both fibre & yarn level for knitted fabric. The vertical flame test, where the fabric hung vertically and burned from the bottom, was used to characterise their burning behaviour. With the vertical flame test, it was found that flame shielding ability of inherently flame retardant fibres towards flammable fibres improves with an increasing proportion of inherently flame retardant fibres in the fabric. Also, fabric structure influences the shielding properties of the flame retardant fibres. A comparison between fibre and yarn level mixing for knitted fabric yarn level mixing was found to have better flame shielding properties. Thesis work points out the issue with flame retardant chemical and presents an alternative approach for conventional flame retardant.

No description available.

The growing demand in portable and compact consumer devices and appliances has resulted in the need for the miniaturisation of electronic components. These miniaturised electronic components are sensitive and susceptible to damage by voltages as low as 20V. Electrically conductive styrenic thermoplastics are widely used in electronic packaging applications to protect these sensitive electronic components against electro-static discharge (ESD) during manufacturing, assembly, storage and shipping. Such ESD applications often require the optimal volume resistance range of ≥ 1.0x105 to < 1.0x108 Ω. The best known method to render styrenic thermoplastics conductive is by the incorporation of conductive fillers, such as carbon black but the main limitation is the difficulty in controlling the conductivity level due to the steep percolation curve. Thus the aim of this research is to develop electrically conductive styrenic thermoplastics by blending several styrenic resins with polymeric conductive additives to achieve optimal volume resistance range for ESD applications with the ease in controlling the conductivity level.

The thesis investigates how one should determine the appropriate transparency of an information processing system from a receiver perspective. Research in the past has suggested that the model should be maximally transparent for what is labeled as ”high stake decisions”. Instead of motivating the choice of a model’s transparency on the non-rigorous criterion that the model contributes to a high stake decision, this thesis explores an alternative method. The suggested method involves that one should let the transparency depend on how well an explanation of the model’s output satisfies the purpose of an explanation. As a result, we do not have to bother if it is a high stake decision, we should instead make sure the model is sufficiently transparent to provide an explanation that satisfies the expressed purpose of an explanation.

There is a research deficit in public administration. We do not adequately ask how the essential concepts of governments that are expressed in political thought are operationalized through administrative mechanisms and then implemented into practice. The current study began addressing this deficit by investigating how the notion of governing approaches has been treated in the political thought of Ronald C. Moe and Moe and Robert S. Gilmour and then exploring how the idea of governing approaches and another essential concept of government, that of inherently governmental, have been operationalized in the administrative device, Office of Management and Budget (OMB) Circular A-76. I utilized a longitudinal qualitative content analysis to determine whether there was support for a change in governing approaches from a Constitutionalist Governing Approach to an Entrepreneurial Governing Approach in the evolution of the meaning of inherently governmental as it was used in OMB Circular A-76, Performance of Commercial Activities, from 1966 to 2003. All the Circulars showed evidence of the Constitutionalist Governing Approach. The project repositions the notion of inherently governmental as a thick political concept, a normative, context-specific idea that a polity must address. It also proposes a research typology to guide investigations of these kinds of ideas. / Ph. D.

La thèse est consacrée à la développement de méthodes efficaces pour la synthèse d'une nouvelle classe d'intrinsèquement chiral calix[4]arènes contenant du phosphore, phosphines et acides phosphoriques avec une certaine disposition mutuelle des groupes fonctionnels sur le bord inférieur du macrocycle, avec un potentiel activité catalytique. La façon optimale fot la synthèse de calix[4]arènes contenant du phosphore par la substitution progressive des hydroxyles phénoliques a été développé afin de concevoir des intrinsèquement chiral calix[4]arènes avec des types de remplacement ABHH et ABCH au bord inférieur du macrocycle. En utilisant ces techniques, la synthèse de la six catalyseurs et efficaces avec chiralité planaire a été réalisée. En utilisant des études de diffraction des rayons X a permis d'étudier la localisation spatiale des groupes fonctionnels. L'utilisation de la réaction de Mitsunobu autorisé à fournir une synthèse de la nouvelle "poche" -comme ligands - calix[4]arènes portant des fragments ferrocényle-phosphines chirales. L'efficacité des nouveaux ligands phosphine synthétisés a été confirmé par l'exemple du modèle de réaction Tsuji-Trost. intéressante dépendance du niveau de sélectivité de la taille du cation de métal de base ajoutée, en raison de l'effet de ligand de chélation du supramoléculaire a été observée. Calix[4]arènes acides phosphoriques a d'abord été appliqués comme organocatalyseurs la série de réactions modèles: aza-Diels-Alder, aza-Mukayiama réaction asymétrique et réaction d'ouverture d'époxydes anneau. Il a été constaté que la plupart des composés synthétisés présentent un degré notable de activitydue catalytique à des caractéristiques de chiralité interne. / The thesis is devoted to the developing of effective methods for the synthesis of new class of inherently chiral phosphorus-containing calix[4]arenes, phosphines and phosphoric acids with a certain mutual arrangement of functional groups on the lower rim of the macrocycle, with potential catalytic activity. The optimal way fot the synthesis of phosphorus-containing calix[4]arenes by the stepwise substitution of the phenolic hydroxyls was developed in order to design inherently chiral calix[4]arenes with ABHH and ABCH replacement types at the lower rim of the macrocycle. By using these techniques, synthesis of six analogues of known and effective catalysts with planar chirality was performed. Using X-ray diffraction studies allowed to investigate spatial location of functional groups. Using of Mitsunobu reaction allowed to provide synthesis of the new "pocket"-like ligands - calix[4]arenes bearing chiral ferrocenyl-phosphines moieties. The effectiveness of the synthesized new phosphine ligands was confirmed by the example of the model Tsuji-Trost reaction. Interesting dependence of the selectivity level on the metal cation size of added base, due to chelation effect of supramolecular ligand was observed. Calix[4]arenes phosphoric acids was first applied as organocatalysts the series of model reactions: aza-Diels-Alder reaction, aza-Mukaiyama asymmetric reaction and epoxides ring opening reaction. It was found that most of the synthesized compounds exhibit a noticeable level of catalytic activitydue to features of internal chirality.