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111.
Amanda J. Gregory Jonathan P. Atkins Daryl Burdon Michael Elliott 《European Journal of Operational Research》2013
The purpose of this paper is to learn from Complex Adaptive Systems (CAS) theory to inform the development of Problem Structuring Methods (PSMs) both in general and in the specific context of marine management. The focus on marine management is important because it is concerned with a CAS (formed through the interconnection between natural systems, designed systems and social systems) which exemplifies their particularly ‘wicked’ nature. Recognition of this compels us to take seriously the need to develop tools for knowledge elicitation and structuring which meet the demands of CAS. In marine management, chief among those tools is the DPSIR (Drivers – Pressures – State Changes – Impacts – Responses) model and, although widely applied, the extent to which it is appropriate for dealing with the demands of a CAS is questionable. Such questioning is particularly pertinent in the context of the marine environment where there is a need to not only recognise a broad range of stakeholders (a question of boundary critique) but also to manage competing knowledge (economic, local and scientific) and value claims. Hence this paper emphasises how a CAS perspective might add impetus to the development of a critical perspective on DPSIR and PSM theory and practice to promote a more systemic view of decision-making and policy development. 相似文献
112.
Amanda C. Garcia Thomas Touzalin Celine Nieuwland Nickson Perini Marc T. M. Koper 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(37):13133-13137
Herein, the effect of the alkali cation (Li+, Na+, K+, and Cs+) in alkaline electrolytes with and without Fe impurities is investigated for enhancing the activity of nickel oxyhydroxide (NiOOH) for the oxygen evolution reaction (OER). Cyclic voltammograms show that Fe impurities have a significant catalytic effect on OER activity; however, both under purified and unpurified conditions, the trend in OER activity is Cs+ > Na+ > K+ > Li+, suggesting an intrinsic cation effect of the OER activity on Fe‐free Ni oxyhydroxide. In situ surface enhanced Raman spectroscopy (SERS), shows this cation dependence is related to the formation of superoxo OER intermediate (NiOO?). The electrochemically active surface area, evaluated by electrochemical impedance spectroscopy (EIS), is not influenced significantly by the cation. We postulate that the cations interact with the Ni?OO? species leading to the formation of NiOO??M+ species that is stabilized better by bigger cations (Cs+). This species would then act as the precursor to O2 evolution, explaining the higher activity. 相似文献
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Analytical and Bioanalytical Chemistry - Accurate measurement and understanding of therapeutic uptake and metabolism is key in the drug development process. This work examines the amount of... 相似文献
114.
Electrospray thrusters using ionic liquid (IL)‐based propellants are quickly gaining popularity in spacecraft design. Mass spectrometry is especially well‐suited to provide important knowledge on the fundamentals of how these systems work and on evaluating their efficiencies and impacts, given that the operating principles of electrospray thrusters closely mimics the mass spectrometry experiment – in both ions are generated by electrospray and then enter a vacuum. Here, electrospray thruster technology and IL‐based propellants are briefly introduced. This introduction is then followed by a discussion of mass spectrometry's current contribution to the study of IL‐based electrospray thrusters – with a focus on electrospray, dissociation, and spectroscopy studies – and a brief discussion of areas ripe for immediate contributions from the mass spectrometry community. 相似文献
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Johnsen Amanda M. Durrant Chad B. Ünlü Kenan 《Journal of Radioanalytical and Nuclear Chemistry》2019,322(3):1529-1535
Journal of Radioanalytical and Nuclear Chemistry - Fifteen tile samples from archaeological digs in central Italy were analyzed for trace element content using comparative neutron activation... 相似文献
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Érica Amanda de Barros Vladimir Eliodoro Costa Dayanne Fabrício Bressan Renata Bruna dos Santos Coscolin Rogério Lopes Vieites Fernando Broetto 《Journal of Radioanalytical and Nuclear Chemistry》2018,315(1):29-37
The effects of the main operation variables on the electrochemical oxidation of simulated tributyl phosphate (TBP) waste by a boron-doped diamond anode are individually studied. The optimum operating conditions are obtained as follows: 4 g L?1 initial TBP concentration, 180 min degradation time, 40 mA cm?2 current density, 0.5 mol L?1 Na2SO4 as the supporting electrolyte, and unadjusted pH of the aqueous phase. Under such conditions, a chemical oxygen demand (COD) removal ratio of 82.3% is achieved, and the energy consumption is 26.16 kWh m?3. A degradation mechanism of TBP is tentatively proposed. 相似文献