Electrolysing mud: Membraneless electrolysis of water for hydrogen production using montmorillonite-rich marine mud

This paper describes a design for a low-cost membraneless water electrolyser for the production of green hydrogen that used a viscous electrolyte of naturally abundant montmorillonite-rich marine mud in a DEFT (divergent electrode flow through) geometry with stainless steel (304) mesh electrodes. The ratio of smectite to non-swelling clays in the mud was 1:2. The electrolyte was prepared by resuspending the mud in tap-water to remove the salt, and NaOH 1 M added to enhance the ionic conductivity, as measured by both Electrochemical Impedance Spectroscopy (EIS) and by the slope of DC current/voltage curves. Successful separation and collection of the hydrogen and oxygen gas was inferred from the ratio of 2:1 in the volumes of hydrogen and oxygen collected. Both acid and alkali treatments were trialled and it was found that, whereas acid treatment flocculated the mud, adding NaOH increased the dispersion, conductivity and viscosity, and reduced clogging. The conductivity of both the 24% dry mass alkali mud and a control 4% dry mass alkali bentonite suspension increased to that of pure NaOH 1 M when repeatedly electrolysed. Hydrogen and oxygen gas was collected for 10% and 24% dry mass muds. The less viscous 10% dry mass mud showed turbulent liquid-like behaviour which led to gas mixing but the 24% mud showed stable, solid-like flow and reliable gas separation. Three components of the energy efficiency of the electrolysis process are reported and discussed – the voltage efficiency of 42%, a gas collection efficiency of 50% and the auxiliary power efficiency of 60%. The overall energy efficiency due to these three contributing efficiencies, was 13% of the Higher Heating Value of 142 MJ/kg H2 for a current density of 45 mA/cm2. This mud electrolyser may still be considered worth developing for an off-grid, low budget site with a low-power source of renewable energy

Peregrine Falcons Nest Successfully During Reconstruction of Bridge Over Ohio River

Peregrine falcons (Falco peregrinus) often nest on bridges over rivers and other waterways, resulting in the need for mitigation planning for bridge maintenance and reconstruction. However, mitigation guidelines for peregrine falcon nests during bridge reconstruction are lacking in the literature. In this paper, we describe the monitoring, spatial, and temporal buffers, nest box installation, and other methods that allowed peregrine falcons to nest successfully on the Milton-Madison (US-421) Bridge during demolition and reconstruction. Construction activities occurred over a 4-year period (2011–2014), and coordination with local road departments and contracted engineers was necessary to accommodate the falcon nest. Nonetheless, construction activities were able to progress without causing major construction expense or delays, and the nesting falcons were able to fledge 14 young during the project

Enhanced Lifetime Cathode for Alkaline Electrolysis Using Standard Commercial Titanium Nitride Coatings

The use of hydrogen gas as a means of decoupling supply from demand is crucial for the transition to carbon-neutral energy sources and a greener, more distributed energy landscape. This work shows how simple commercially available titanium nitride coatings can be used to extend the lifetime of 316 grade stainless-steel electrodes for use as the cathode in an alkaline electrolysis cell. The material was subjected to accelerated ageing, with the specific aim of assessing the coating’s suitability for use with intermittent renewable energy sources. Over 2000 cycles lasting 5.5 days, an electrolytic cell featuring the coating outperformed a control cell by 250 mV, and a reduction of overpotential at the cathode of 400 mV was observed. This work also confirms that the coating is solely suitable for cathodic use and presents an analysis of the surface changes that occur if it is used anodically

The Hydrogen Bike: Communicating the Production and Safety of Green Hydrogen

As the international community aims to reduce its reliance on fossil fuels, green hydrogen has great potential to replace methane as a clean source of fuel. A novel public engagement activity, The Hydrogen Bike, has been developed to demonstrate the production and use of green hydrogen from water. The aim of the activity is to educate, entertain and inform young people and adults so that they have an opportunity to form an opinion about the use of hydrogen as a fuel. Using a novel two-part data collection system participants are briefly surveyed for their opinion on hydrogen before and after participating in The Hydrogen Bike activity. Through this we have found that most participants (73%) are considered to have no opinion or a neutral opinion on hydrogen before participating in The Hydrogen Bike activity. After participation 88% of those who were originally neutral or had no opinion on hydrogen self-reported a positive feeling about hydrogen. The method of data collection was quick, intuitive and suitable for an audience attracted from passing footfall

Evolving the Face of a Criminal: How to Search a Face Space More Effectively

Witnesses and victims of serious crime are often required to construct a facial composite, a visual likeness of a suspect’s face. The traditional method is for them to select individual facial features to build a face, but often these images are of poor quality. We have developed a new method whereby witnesses repeatedly select instances from an array of complete faces and a composite is evolved over time by searching a face model built using PCA. While past research suggests that the new approach is superior, performance is far from ideal. In the current research, face models are built which match a witness’s description of a target. It is found that such ‘tailored’ models promote better quality composites, presumably due to a more effective search, and also that smaller models may be even better. The work has implications for researchers who are using statistical modelling techniques for recognising faces

NGC 5846-UDG1: A Galaxy Formed Mostly by Star Formation in Massive, Extremely Dense Clumps of Gas

It has been shown that ultra-diffuse galaxies (UDGs) have higher specific frequencies of globular clusters, on average, than other dwarf galaxies with similar luminosities. The UDG NGC 5846-UDG1 is among the most extreme examples of globular cluster-rich galaxies found so far. Here we present new Hubble Space Telescope observations and analysis of this galaxy and its globular cluster system. We find that NGC 5846-UDG1 hosts 54 ± 9 globular clusters, three to four times more than any previously known galaxy with a similar luminosity and higher than reported in previous studies. With a galaxy luminosity of L V,gal ≈ 6 × 107 L ⊙ (M ⋆ ≈ 1.2 × 108 M ⊙) and a total globular cluster luminosity of L V,GCs ≈ 7.6 × 106 L ⊙, we find that the clusters currently comprise ∼13% of the total light. Taking into account the effects of mass loss from clusters during their formation and throughout their lifetime, we infer that most of the stars in the galaxy likely formed in globular clusters, and very little to no normal low-density star formation occurred. This result implies that the most extreme conditions during early galaxy formation promoted star formation in massive and dense clumps, in contrast to the dispersed star formation observed in galaxies today

Understanding the multiframe caricature advantage for recognizing facial composites.

Eyewitnesses often construct a ‘composite’ face of a person they saw commit a crime, a picture that police use to identify suspects. We described a technique (Frowd et al., 2007, Visual Cognition, 15, 1-31) based on facial caricature to facilitate recognition of these images: correct naming substantially improves when composites are seen with progressive positive caricature, where distinctive information is enhanced, and then with progressive negative caricature, the opposite. Over the course of four experiments, the underpinnings of this mechanism are explored. Positive-caricature levels were found to be largely responsible for improving naming of composites, with some benefit from negative-caricature levels. Also, different frame-presentation orders (forward, reverse, random, repeated) facilitated equivalent naming benefit relative to static composites. Overall, the data indicate that composites are usually constructed as negative caricatures

Evolving the memory of a criminal’s face: methods to search a face space more effectively

Witnesses and victims of serious crime are often required to construct a facial composite, a visual likeness of a suspect’s face. The traditional method is for them to select individual facial features to build a face, but often these images are of poor quality. We have developed a new method whereby witnesses repeatedly select instances from an array of complete faces and a composite is evolved over time by searching a face model built using PCA. While past research suggests that the new approach is superior, performance is far from ideal. In the current research, face models are built which match a witness’s description of a target. It is found that such ‘tailored’ models promote better quality composites, presumably due to a more effective search, and also that smaller models may be even better. The work has implications for researchers who are using statistical modelling techniques for recognising faces

Evolving the face of a criminal: how to search a face space more effectively

Witnesses and victims of serious crime are often required to construct a facial composite, a visual likeness of a suspect’s face. The traditional method is for them to select individual facial features to build a face, but often these images are of poor quality. We have developed a new method whereby witnesses repeatedly select instances from an array of complete faces and a composite is evolved over time by searching a face model built using PCA. While past research suggests that the new approach is superior, performance is far from ideal. In the current research, face models are built which match a witness’s description of a target. It is found that such 'tailored' models promote better quality composites, presumably due to a more effective search, and also that smaller models may be even better. The work has implications for researchers who are using statistical modelling techniques for recognising faces

Same data, different analysts: variation in effect sizes due to analytical decisions in ecology and evolutionary biology

Gould E, Fraser H, Parker T, et al. Same data, different analysts: variation in effect sizes due to analytical decisions in ecology and evolutionary biology. 2023.Although variation in effect sizes and predicted values among studies of similar phenomena is inevitable, such variation far exceeds what might be produced by sampling error alone. One possible explanation for variation among results is differences among researchers in the decisions they make regarding statistical analyses. A growing array of studies has explored this analytical variability in different (mostly social science) fields, and has found substantial variability among results, despite analysts having the same data and research question. We implemented an analogous study in ecology and evolutionary biology, fields in which there have been no empirical exploration of the variation in effect sizes or model predictions generated by the analytical decisions of different researchers. We used two unpublished datasets, one from evolutionary ecology (blue tit, Cyanistes caeruleus, to compare sibling number and nestling growth) and one from conservation ecology (Eucalyptus, to compare grass cover and tree seedling recruitment), and the project leaders recruited 174 analyst teams, comprising 246 analysts, to investigate the answers to prespecified research questions. Analyses conducted by these teams yielded 141 usable effects for the blue tit dataset, and 85 usable effects for the Eucalyptus dataset. We found substantial heterogeneity among results for both datasets, although the patterns of variation differed between them. For the blue tit analyses, the average effect was convincingly negative, with less growth for nestlings living with more siblings, but there was near continuous variation in effect size from large negative effects to effects near zero, and even effects crossing the traditional threshold of statistical significance in the opposite direction. In contrast, the average relationship between grass cover and Eucalyptus seedling number was only slightly negative and not convincingly different from zero, and most effects ranged from weakly negative to weakly positive, with about a third of effects crossing the traditional threshold of significance in one direction or the other. However, there were also several striking outliers in the Eucalyptus dataset, with effects far from zero. For both datasets, we found substantial variation in the variable selection and random effects structures among analyses, as well as in the ratings of the analytical methods by peer reviewers, but we found no strong relationship between any of these and deviation from the meta-analytic mean. In other words, analyses with results that were far from the mean were no more or less likely to have dissimilar variable sets, use random effects in their models, or receive poor peer reviews than those analyses that found results that were close to the mean. The existence of substantial variability among analysis outcomes raises important questions about how ecologists and evolutionary biologists should interpret published results, and how they should conduct analyses in the future