The need for energy storage to balance intermittent and inflexible electricity supply with demand is driving interest in conversion of renewable electricity via electrolysis into a storable gas. But, ...high capital cost and uncertainty regarding future cost and performance improvements are barriers to investment in water electrolysis. Expert elicitations can support decision-making when data are sparse and their future development uncertain. Therefore, this study presents expert views on future capital cost, lifetime and efficiency for three electrolysis technologies: alkaline (AEC), proton exchange membrane (PEMEC) and solid oxide electrolysis cell (SOEC). Experts estimate that increased R&D funding can reduce capital costs by 0–24%, while production scale-up alone has an impact of 17–30%. System lifetimes may converge at around 60,000–90,000 h and efficiency improvements will be negligible. In addition to innovations on the cell-level, experts highlight improved production methods to automate manufacturing and produce higher quality components. Research into SOECs with lower electrode polarisation resistance or zero-gap AECs could undermine the projected dominance of PEMEC systems. This study thereby reduces barriers to investment in water electrolysis and shows how expert elicitations can help guide near-term investment, policy and research efforts to support the development of electrolysis for low-carbon energy systems.
•10 experts project cost & performance for alkaline, PEM and solid-oxide electrolysis.•6 experts believe PEM will be the dominant electrolysis technology by 2030.•Production scale-up has more impact on cost than increased R&D funding.•Specific technical, manufacturing and value-chain innovations are named.•Insights could help guide near-term investment, policy and research efforts.
refnx is a model‐based neutron and X‐ray reflectometry data analysis package written in Python. It is cross platform and has been tested on Linux, macOS and Windows. Its graphical user interface is ...browser based, through a Jupyter notebook. Model construction is modular, being composed from a series of components that each describe a subset of the interface, parameterized in terms of physically relevant parameters (volume fraction of a polymer, lipid area per molecule etc.). The model and data are used to create an objective, which is used to calculate the residuals, log‐likelihood and log‐prior probabilities of the system. Objectives are combined to perform co‐refinement of multiple data sets and mixed‐area models. Prior knowledge of parameter values is encoded as probability distribution functions or bounds on all parameters in the system. Additional prior probability terms can be defined for sets of components, over and above those available from the parameters alone. Algebraic parameter constraints are available. The software offers a choice of fitting approaches, including least‐squares (global and gradient‐based optimizers) and a Bayesian approach using a Markov‐chain Monte Carlo algorithm to investigate the posterior distribution of the model parameters. The Bayesian approach is useful for examining parameter covariances, model selection and variability in the resulting scattering length density profiles. The package is designed to facilitate reproducible research; its use in Jupyter notebooks, and subsequent distribution of those notebooks as supporting information, permits straightforward reproduction of analyses.
The refnx Python modules for neutron and X‐ray reflectometry data analysis are introduced. A sample analysis illustrates a Bayesian approach using a Markov‐chain Monte Carlo algorithm to understand the confidence in the fit parameters.
Micro‐/nanorobots (m‐bots) have attracted significant interest due to their suitability for applications in biomedical engineering and environmental remediation. Particularly, their applications in ...in vivo diagnosis and intervention have been the focus of extensive research in recent years with various clinical imaging techniques being applied for localization and tracking. The successful integration of well‐designed m‐bots with surface functionalization, remote actuation systems, and imaging techniques becomes the crucial step toward biomedical applications, especially for the in vivo uses. This review thus addresses four different aspects of biomedical m‐bots: design/fabrication, functionalization, actuation, and localization. The biomedical applications of the m‐bots in diagnosis, sensing, microsurgery, targeted drug/cell delivery, thrombus ablation, and wound healing are reviewed from these viewpoints. The developed biomedical m‐bot systems are comprehensively compared and evaluated based on their characteristics. The current challenges and the directions of future research in this field are summarized.
The design and fabrication, functionalization, actuation, and tracking of individual and a swarm of micro/nanorobots are an indispensable part for achieving biomedical applications. How to combine and integrate all the four aspects together and realize a biomedical therapeutic function using the micro‐/nanorobotic strategy is discussed.
Accounting for energy use by fishes has been taking place for over 200 years. The original, and continuing gold standard for measuring energy use in terrestrial animals, is to account for the waste ...heat produced by all reactions of metabolism, a process referred to as direct calorimetry. Direct calorimetry is not easy or convenient in terrestrial animals and is extremely difficult in aquatic animals. Thus, the original and most subsequent measurements of metabolic activity in fishes have been measured via indirect calorimetry. Indirect calorimetry takes advantage of the fact that oxygen is consumed and carbon dioxide is produced during the catabolic conversion of foodstuffs or energy reserves to useful ATP energy. As measuring CO2 in water is more challenging than measuring O2, most indirect calorimetric studies on fishes have used the rate of O2 consumption. To relate measurements of O2 consumption back to actual energy usage requires knowledge of the substrate being oxidized. Many contemporary studies of O2 consumption by fishes do not attempt to relate this measurement back to actual energy usage. Thus, the rate of oxygen consumption (M˙O2) has become a measurement in its own right that is not necessarily synonymous with metabolic rate. Because all extant fishes are obligate aerobes (many fishes engage in substantial net anaerobiosis, but all require oxygen to complete their life cycle), this discrepancy does not appear to be of great concern to the fish biology community, and reports of fish oxygen consumption, without being related to energy, have proliferated. Unfortunately, under some circumstances, these measures can be quite different from one another. A review of the methodological history of the two measurements and a look towards the future are included.
BACKGROUND: Environmental conditions, such as water supply, temperature and salinity, strongly affect plant growth and development. Extremes of these conditions (abiotic stresses) adversely affect ...many different mechanisms associated with plant responses and adaptation to stress: photosynthetic mechanisms, e.g. stomatal control of CO₂ diffusion, photosystem II repair, ribulose bisphosphate carboxylase/oxygenase (Rubisco) activity and scavenging of reactive oxygen species (ROS), are susceptible to damage, and photosynthetic efficiency can be greatly decreased. Responses and adaptations require differential gene expression, which is regulated by specific transcription factors (TFs). SCOPE: The role and regulation of several TFs involved in abiotic stress response pathways are considered, with emphasis on new findings regarding expression of genes related to both stomatal and non-stomatal limitations to CO₂ photosynthetic assimilation. CONCLUSIONS: Many TFs, belonging to different families (e.g. MYB, bZIP and DREB), have been related to abiotic stress responses; however, only a few are known to regulate the expression of photosynthesis-related genes in response to stress. Several TFs belonging to the MYB family play an important role in both stomatal and non-stomatal responses by regulation of stomatal numbers and sizes, and metabolic components, respectively. To obtain more insight into this area of potentially large agronomic impact, it is essential to identify and functionally characterize new TFs that mediate the stress responses regulating the expression of genes associated with photosynthesis and related metabolism.
The use of
N
-heterocyclic carbenes (NHCs) in chemistry has developed rapidly over the past twenty years. These interesting compounds are predominantly employed in organometallic chemistry as ligands ...for various metal centres, and as organocatalysts able to mediate an exciting range of reactions. However, the sheer number of NHCs known in the literature can make the appropriate choice of NHC for a given application difficult. A number of metrics have been explored that allow the electronic properties of NHCs to be quantified and compared. In this review, we discuss these various metrics and what they can teach about the electronic properties of NHCs. Data for approximately three hundred NHCs are presented, obtained from a detailed survey of the literature.
The wide range of NHCs known in the literature can make choosing an NHC for a given application difficult. In this review, the electronic properties of NHCs are discussed, as well as the various methods by which they can be quantified. Data for
ca.
three hundred NHCs are provided.
Dielectric Polymer Nanocomposites provides the first in-depth discussion of nano-dielectrics, an emerging and fast moving topic in electrical insulation. The text begins with an overview of the ...background, principles and promise of nanodielectrics, followed by a discussion of the processing of nanocomposites and then proceeds with special considerations of clay based processes, mechanical, thermal and electric properties and surface properties as well as erosion resistance. Carbon nanotubes are discussed as a means of creation of non linear conductivity, the text concludes with a industrial applications perspective.
Microchimerism (Mc) refers to the harboring of a small number of cells (or DNA) that originated in a different individual. Naturally acquired Mc derives primarily from maternal cells in her progeny, ...or cells of fetal origin in women. Both maternal and fetal Mc are detected in hematopoietic cells including T and B cells, monocyte/macrophages, natural killer (NK) cells and granulocytes. Mc appears also to generate cells such as myocytes, hepatocytes, islet β cells and neurons. Here, the detrimental and beneficial potential of Mc is examined. The prevalence, diversity and durability of naturally acquired Mc, including in healthy individuals, indicates that a shift is needed from the conventional paradigm of ‘self versus other’ to a view of the normal ‘self’ as constitutively chimeric.
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