Applications of amine gelling agents in fire technology

A novel gelatin system for use in oil spills at sea provides rapid immobilization of liquids upon demand.     

The economic potential of precision nitrogen application with wheat based on plant sensing

Plant-based precision nitrogen fertilizer application technologies have been developed as a way to predict and precisely meet nitrogen needs. Equipment necessary for precision application of nitrogen, based on sensing of growing wheat plants in late winter, is available commercially, but adoption has been slow. This article determines the expected profit from using a plant-sensing system to determine winter wheat nitrogen requirements. We find that plant-sensing systems have the potential to be more profitable than traditional nonprecise systems, but the existing system simulated was roughly breakeven with a traditional system.     

Crowding standards at Petra Archaeological Park: a comparative study of McKercher's five types of heritage tourists

To achieve sustainability in heritage tourism, tourists should be placed at the heart of the management and planning processes. Indicators and standards-based frameworks were developed in the field of outdoor recreation management to manage and measure crowding and other problematic issues in parks and related areas. Using normative theory and visual research methods, this article aims to examine crowding standards of tourists at Petra Archaeological Park, and compare these standards between the types of heritage tourists suggested by a model developed by Bob McKercher. Results showed that tourists’ acceptability levels go down with an increasing number of tourists, and tourists who are highly motivated to visit heritage sites (i.e. purposeful and sightseeing heritage tourists) had the most restrictive acceptable number of tourists at the park. The normative standards formulated in this article provided a guidance to manage crowding at Petra.