Browsing by Author "Gounder R"

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    Climate change, vulnerability and well-being in the Pacific region
    (Taylor and Francis Group on behalf of the New Zealand Association of Economists Incorporated, 2024-05-12) Gounder R
    The Pacific region has experienced vast adverse effects from climate change impacting the peoples’ livelihoods both in these nations’ urban and rural areas. Countries association between socio-economic performance and livelihoods have been adversity impacted by climatic hazards and vulnerabilities on nations’ economic performance impacting the societal outcomes. An assessment of the Pacific’s climate change, vulnerability and well-being is presented in general and a case study of Fiji in particular. The Pacific islands require resources invested in environmental education, and climate change and trade policy linkages to benefit the islands, future returns to individuals and higher levels of satisfied basic needs to reduce vulnerabilities.
  • Thumbnail Image
    Item
    Quantification of extracrystalline acid sites in MFI zeolites after post-synthetic passivation treatments using mesitylene benzylation kinetics
    (Royal Society of Chemistry, 2024-01-25) Ezenwa S; Hopping GM; Sauer ED; Scott T; Mack S; Gounder R
    Brønsted acid sites (H+) located at extracrystalline surfaces of zeolites influence catalyst reactivity, selectivity, and deactivation behavior. The number of extracrystalline H+ sites is difficult to quantify reliably using spectroscopic or titrimetric techniques when present in dilute quantities, such as after post-synthetic surface passivation treatments. Here, methods to quantify extracrystalline H+ sites on MFI zeolites were developed by measuring the kinetics of mesitylene benzylation with dibenzyl ether to form 1,3,5-trimethyl-2-benzylbenzene, which is sterically prevented from forming at intracrystalline H+ sites within microporous voids. These methods were applied to investigate MFI zeolite samples that were systematically treated using ammonium hexafluorosilicate (AHFS) with varying treatment durations, AHFS concentrations, and numbers of successive treatment cycles. Rates of mesitylene benzylation with dibenzyl ether (363 K) were measured on a suite of MFI samples with known amounts of external H+ sites (0.01-0.15 H+ext/Al), quantified by 2,6-di-tertbutylpyridine titration, to determine the intrinsic zero-order rate constant for mesitylene benzylation (per H+ext). Quantification of zero-order rate constants on post-synthetically treated MFI zeolites shows that AHFS treatments selectively passivate extracrystalline H+ sites with efficacies that depend on the specific treatment conditions used. The kinetic methods developed here enable quantifying extracrystalline acid sites in amounts below the detection limits of common spectroscopic and titration techniques on various small-pore and medium-pore zeolites, enabling assessments of the efficacy of post-synthetic surface passivation treatments and rigorous evaluation of the reactivity of extracrystalline H+ sites during acid catalysis.
  • Thumbnail Image
    Item
    Regional destination attributes that attract domestic tourists: the role of man-made venues for leisure and recreation.
    (2021-06) Camacho-Murillo A; Gounder R; Richardson S
    This paper examines the influence of man-made attractions for leisure and recreation on domestic tourists' preferences amongst regional destinations, and the moderating role of these attractions on the negative effect of distance on tourists' choices. A mixed multinomial logit model is employed for 368 cities in Colombia grouped into 28 provinces. Factor analysis is utilised to identify the latent variable that groups several man-made attractions for leisure and recreation. Results show that domestic tourists' choices of a regional destination increase as the number of man-made attractions for leisure and recreation rises, although there is taste heterogeneity between tourists explained by their city of origin. Findings also show that the decline in domestic tourists' preferences for a regional destination due to increases in travel distance can be lessened through the construction and/or enhancement of man-made venues for leisure and recreation in the destination; a strategy that can serve to reduce monetary poverty in distant destinations that have attributes to attract tourists.