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131.
Metallic structured packings have found increasing use in the cryogenic distillation of air. An experimental program was performed to test the flammability of selected metal packings under simulated high oxygen concentration operating conditions. Aluminum flammability in gaseous oxygen has been shown to be very dependent upon argon dilution, and in the presence of liquid oxygen, strong energy releases have been observed. Brass packing exhibited an unexpectedly high relative flammability whereas copper has been found to be non-flammable in all tested oxygen purities. These findings suggest the use of copper structured packing in higher purity GOX/LOX regions of an air separation distillation column and aluminum structured packing in the remainder of the column. 相似文献
132.
An approach to evaluate the acute impacts from simulated accidental releases of chlorine and ammonia
The manner in which specific chemicals are used is studied in order to identify plausible release scenarios and the probability of their occurrence. 相似文献
133.
Jonathan L. Brockwell 《Process Safety Progress》1990,9(2):98-102
A decomposition limit equation applicable to liquid ethylene oxide storage conditions based on recently obtained data is presented. Comparison is made with a second correlation equation developed from literature data. Adjustment of predicted decomposition limits to produce recommended safe operating limits is discussed. 相似文献
134.
Natalie L. B. Knowles 《Journal of Sustainable Tourism》2019,27(3):380-397
As global temperatures increase, does accelerating climate change represent an existential crisis or a manageable challenge for the ski industry? Despite considerable evidence demonstrating the global ski industry is in the early stages of a climate-induced transition, global research on ski industry stakeholder perspectives shows varied levels of climate risk awareness, a focus on future vulnerability, and limited engagement in adaptation. Within North America, research has focussed on the physical climatic impacts to ski operations and possible skier responses, yet there lacks insight into industry perceptions on current and future climate vulnerability. This study fills this important knowledge gap using a Delphi survey to engage 52 leaders from across the continent in a dialogue on strategic climate responsiveness. Results demonstrate North American ski industry leaders’ climate risk perceptions range widely, and opinions diverge over if or how to respond at both an industry and destination scale. Simultaneously, industry experts believe mountain tourists increasingly value nature-based activities, place-bound products, and corporate responsibility. Analysing industry leaders’ responses through Enlightened Stakeholder theory highlights how aligning supply-side environmental management with demand-side tourist experiences may create opportunities for new partnerships, innovations, policies, and strategies needed to achieve climate-resilient and sustainable futures. 相似文献
135.
The sustainable livelihoods (SL) approach offers a holistic framework and a practical toolkit to analyze tourism's impacts and interactions within a community. This study argues that the usefulness of the SL approach in tourism can be enhanced by ensuring that the approach is built on a genuine people-centered starting point. The exploration of the local community's representations of, and aspirations for, their roles in tourism as a future livelihood choice meets this need. To verify the value of this approach empirically, this study examined the case of Lhasa, Tibet, and local youth as the research respondents. The findings suggest that the young hosts in Lhasa urban area were heterogeneous in their responses to tourism as a future livelihood choice. They fell into four subgroups: in-betweeners, ambivalent supporters, alternative supporters, and lovers. Further, this study examined the profiles of these four subgroups and explored their responses. The study enhances the SL approach by taking tourism as an example and clearly defining the departure point for its adoption within the context of broader livelihoods portfolios. Additionally, it suggests some potential directions for tailored management strategies to meet youth and community perspectives. 相似文献
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Nicole L. Davis 《Journal of Teaching in Travel & Tourism》2016,16(3):228-232
A well-designed flipped course requires a significant amount of planning and preparation, but has great benefit to both students and instructor. Using Bloom’s Taxonomy as a guide, one can design effective online and in-class components that maximize benefits to students. A flipped classroom allows students more time to interact with peers and their teacher, and collaborate with teams. This paper will describe how one tourism educator flipped an advanced marketing course, as well as the technology tools used in content creation. 相似文献