3 resultados para ROP

em Queensland University of Technology - ePrints Archive


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Using an in situ-generated calcium-based initiating species derived from pentaerythritol, the bulk synthesis of well-defined 4-arm star poly(L-lactide) oligomers has been studied in detail. The substitution of the traditional initiator, stannous octoate with calcium hydride allowed the synthesis of oligomers that had both low PDIs and a comparable number of polymeric arms (3.7 – 3.9) to oligomers of similar molecular weight. Investigations into the degree of control observed during the course of the polymerization found that the insolubility of pentaerythritol in molten L-lactide resulted in an uncontrolled polymerization only when the feed mole ratio of L-lactide to pentaerythritol was 13. At feed ratios of 40 and greater, a pseudo-living polymerization was observed. As part of this study, in situ FT-Raman spectroscopy was demonstrated to be a suitable method to monitor the kinetics of the ring-opening polymerization (ROP) of lactide. The advantages of using this technique rather than FT-IR-ATR and 1H NMR for monitoring L-lactide consumption during polymerization are discussed.

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With increasing motorisation, road safety has become a major concern within Oman. Internationally, traffic policing plays a major role in improving road safety. Within Oman, the Royal Oman Police's (ROP) Directorate General of Traffic is responsible for policing traffic laws. Many common enforcement approaches originate from culturally different jurisdictions. The ROP is a relatively young policing force and may have different operational practices. Prior to applying practices from other jurisdictions it is important to understand the beliefs and expectations within the Directorate General of Traffic. Further, there is a need for individuals to understand their role and what is expected of them. Therefore, it is important to explore the agreement between levels of the ROP to determine how strategies and expectations transfer within the organisation. Interviews were conducted with 19 police officers from various levels of the ROP. A number of themes and findings emerged. Individuals at the upper level of the traffic police had a clear knowledge of the role of the ROP, believed that traffic police know what is expected of them, are well trained in their role and can have a very positive influence on road safety. These beliefs were less certain lower within the organisations with traffic officers having little knowledge of the role of the ROP or what was expected of them, felt undertrained, and believed their peers have little positive impact on road safety. There is a need to address barriers within the ROP in order to positively impact road safety.

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Objectives Studies from different parts of the world have indicated that the impact of road traffic incidents disproportionally affects young adults. Few known studies have been forthcoming from Arabian Gulf countries. Within Oman, a high proportion of the population is under the age of 20. Coupled with the drastic increase of motorization in recent years there is a need to understand the state of road safety among young people in Oman. The current research aimed to explore the prevalence and characteristics of road traffic injuries among young drivers aged 17-25 years. Methods Crash data from 2009-2011 was extracted from the Directorate General of Traffic, Royal Oman Police (ROP) database in Oman. The data was analyzed to explore the impact of road crashes on young people (17-25 years), the characteristics of young driver crashes and how these differ from older drivers and to identify key predictors of fatalities in young driver crashes. Results Overall, young people were over-represented in injuries and fatalities within the sample time period. While it is true that many young people in crashes were driving at the time, it was also evident that young people were often a victim in a crash caused by someone else. Thus, to reduce the impact of road crashes on young people, there is a need to generally address road safety within Oman. When young drivers were involved in crashes they were predominantly male. The types of crashes these drivers have can be broadly attributed to risk taking and inexperience. Speeding and night time driving were the key risk factors for fatalities. Conclusion The results highlight the need to address young driver safety in Oman. From these findings, the introduction of a graduated driver licensing system with night time driving restrictions could significantly improve young driver safety.