Available online xxxKeywords: Microalgae Carbon dioxide Mixotrophic growth Synergistic Biodiesel Dissolved inorganic carbon a b s t r a c tIn recent years microalgae have attracted significant interest as a potential source of sustainable biofuel. Mixotrophic microalgae are able to simultaneously photosynthesise while assimilating and metabolising organic carbon. By combining autotrophic and heterotrophic metabolic pathways biomass productivity can be significantly increased. In this study, acetate-fed mixotrophic Micractinium inermum cultures were found to have a specific growth rate 1.74 times the sum of autotrophic and heterotrophic growth. It was hypothesised that gas exchange between the two metabolic pathways within mixotrophic cultures may have prevented growth limitation and enhanced growth. To determine the extent of synergistic gas exchange and its influence on metabolic activity, dissolved inorganic carbon (DIC), dissolved oxygen (DO) and photosynthesis and respiration rates were measured under different trophic conditions. A 32.7 fold and 2.4 fold increase in DIC and DO concentrations, relative to autotrophic and heterotrophic cultures respectively, were coupled with significant increases in rates of photosynthesis and respiration. These data strongly support the hypothesis of mixotrophic gas exchange within M. inermum cultures. In addition to enhanced growth, this phenomenon may provide reductions in aeration and oxygen stripping costs related to microalgae production.Please cite this article in press as: Smith RT, et al., Synergistic carbon metabolism in a fast growing mixotrophic freshwater microalgal species Micractinium inermum, Biomass and Bioenergy (2015), http://dx.
Due to the COVID-19 pandemic, universities across the world have curtailed face to face teaching. Associated with this is the halt to the delivery of the practical experience required of engineering students. The Multidisciplinary Engineering Education (MEE) team at The University of Sheffield have responded to this problem in an efficient and effective way by recording laboratory experiences and putting videos, quizzes and data online for students to engage with. The focus of this work was on ensuring all Learning Outcomes (LOs) for modules and courses were preserved. Naturally, practical skills cannot be easily provided using this approach, but it is an effective way of getting students to interact with real data, uncertainty and equipment which they cannot access directly. A number of short case studies from across the range of engineering disciplines are provided to inspire and guide other educators in how they can move experiments on line in an efficient and effective manner. No student feedback is available at the time of writing, but anecdotal evidence is that this approach is at least acceptable for students and a way of collecting future feedback is suggested. The effort expended on this approach and the artefacts produced will support student learning after the initial disruption of the lockdown has passed.
Due to the COVID-19 pandemic, universities across the world have curtailed face to face teaching. Associated with this is the halt to the delivery of the practical experience required of engineering students. The Multidisciplinary Engineering Education (MEE) team at The University of Sheffield have responded to this in an efficient and effective way by recording the laboratory experiences and putting videos, quizzes and data online for students to engage with. The focus being on ensuring Learning Outcomes for modules and courses have been preserved. Naturally, practical skills cannot be easily provided using this approach, but it is an effective way of getting students to interact with real data, uncertainty and equipment which they cannot access directly .A number of short case studies from across the range of engineering are provided to inspire and guide other educators in how they can move experiments on line in an efficient and effective manner.No student feedback is available at the time of writing, but anecdotal evidence is that this approach is at least acceptable for students and a way of collecting this is suggested. The effort that has gone into this approach and the artefacts produced will support student learning after the initial disruption of the lockdown has passed.
A major cost component for large‐scale algal cultivation is the medium. In this study, a significantly higher growth rate was found for Nannochloropsis salina in an inexpensive medium of seawater and agricultural fertilizer than was reached in the f/2 medium. A key difference between this new low‐cost medium and the f/2 medium is the nitrogen source. In the conditions tested herein, with aeration using air, biomass productivity reached 0.5496 g L−1 day−1 after 10 days in the low‐cost medium compared with 0.1215 g L−1 day−1 in the f/2 medium. The lipid productivity of algae grown in the low‐cost medium was also higher than that in the f/2 medium (0.1281 g L−1 day−1 versus 0.0432 g L−1 day−1). The strong linear correlation (R2 = 0.9721) between chlorophyll content and biomass concentration demonstrated that this new medium can support healthy and consistent growth of algal cells. The results suggest that it would be preferable to feed the algae for large‐scale biodiesel production with agricultural waste stream or untreated swine wastewater containing high levels of ammonia rather than treated effluent in which the ammonia/urea has been oxidized to nitrate. © 2014 American Institute of Chemical Engineers Environ Prog, 34: 297–303, 2015
The nature of fluid mechanics makes experimentation an important part of a course taught on the subject. Presented here is the application of a novel, large-scale multidisciplinary model of practical education in a fluids engineering laboratory. The advantages of this approach include efficiencies through the economy of scale leading to better pedagogy for students. The scale justifies dedicated academic resources to focus on developing laboratory classes and giving specific attention to designing activities that meet learning outcomes. Four examples of applying this approach to fluid mechanics experiments are discussed, illustrating tactics that have been developed and honed through many repeated instances of delivery. “The measurement lab” uses a flow measurement context to teach identifying and managing general experimental uncertainty. In this lab, new students, unfamiliar with fluid mechanics, are guided through a process to gain understanding that can be applied to all future experimental activities. The “pressure loss in pipes” lab discusses the advantage of and process for sharing equipment and teaching resources between multiple cohorts. Here, the provision for students is adapted for context, such as the degree program or year of study. The “weirs big and small” lab provides a methodology for teaching the power of dimensional analysis to mechanical engineers using a field of fluid mechanics that is outside their usual theoretical studies. Finally, the “spillway design” lab discusses mechanisms for delivering independent, open-ended student experiments at scale, without excessive staff resource requirements.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.