Catalytic CO2/CO Reduction: Gas, Aqueous and Aprotic phase

The catalytic reduction of CO2/CO is key to reducing carbon footprint and producing the chemical building blocks needed for society. In this work, we performed a theoretical investigation of the differences and similarities of the CO2/CO catalytic reduction reactions in the gas, aqueous solution, and aprotic solution. We demonstrate that binding energy serves as a good descriptor for gaseous and aqueous phases and allows categorizing catalysts by reduction products. The CO vs. O and CO vs. H binding energies for these phases gives a convenient mapping of catalysts regarding their main product for the CO2/CO reduction reactions. However, for the aprotic phase, descriptors alone are insufficient for the mapping. We show that a microkinetic model (including the CO and H binding energies) allows spanning and interpreting the reaction space for the aprotic phase.

Selected Aspects of Pavement Texture Influence on Tire Rolling Resistance

Tire rolling resistance has a significant influence on fuel consumption in cars and trucks and on CO2 emissions. Rolling resistance depends on the tire construction, pavement texture and stiffness, as well as environmental and traffic conditions. This article presents a pilot study on the impact of pavement texture on the rolling resistance of passenger car tires. Reasons why Mean Profile Depth is not a good descriptor of pavement characteristics from the point of view of rolling resistance are presented, and an experimental method which takes into account tire deformation on texture and partial enveloping is described. A method based on testing the volume and depth of tire tread deformation is also proposed.

Can NOx reduction by CO react over carbon-based single-atom catalysts at low temperatures? A theoretical study

First principles studies combined with the microkinetic analysis were performed to study the reliability and reaction mechanisms of single-atom doped graphene (SADGr) materials in catalyzing NOx reduction with CO. By screening the 3d transition metals (Sc-Zn) and group-IV elements (Si and Ge), it was found that the Ti and Co doped graphene sheets (TiGr and CoGr) respectively own excellent catalytic activities in the NO/NO2-to-N2O and the N2O-to-N2 processes at low temperatures. Therefore, the TiGr/CoGr composite can be a promising catalyst in NOx reduction with CO. It was further revealed the combination of adsorption energy and electronegativity was a good descriptor to predict the activation energies. The obtained results can provide useful information for rational design of carbon-based single-atom catalysts for NOx reduction by CO at low temperatures.

Thermodynamic insights into strong metal–support interaction of transition metal nanoparticles on titania: simple descriptors for complex chemistry

Using ab initio modelling, we demonstrate that a simple parameter – alloy formation energy – is a good descriptor of an interaction strength between metal substrates and oxide monolayers, which allows constructing structure–material–environment maps.

Environment and sex control lifespan and telomere length in wild-derived African killifish

ABSTRACTTelomere length is correlated positively with longevity at the individual level, but negatively when compared across species. Here, we tested the association between lifespan and telomere length in African annual killifish. We analyzed telomere length in 18 Nothobranchius strains derived from diverse habitats and measured the laboratory lifespan of 14 strains of N. furzeri and N. kadleci. We found that males had shorter telomeres than females. The longest telomeres were recorded in strains derived from dry region where male lifespans were shortest. At the individual level, we detected a weak negative association between rapid juvenile growth and shorter telomeres in early adulthood. Overall, average telomere length was a good descriptor of telomere length distribution. However, within-individual telomere length spread was not related to any pattern. This substantial variation in telomere length between strains from different environments provides killifish as powerful tool to understand the evolutionarily adaptive value of telomere length.

Living Precarious Lives? Time and Temporality in Visual Arts Careers

Although precarity has always been a characteristic feature of artistic labour, many critics now claim it is becoming more widespread and engrained. However, while the idea of precarity offers a good descriptor of the conditions of artistic labour, it also has its limits. Firstly, it tends to gloss over social differences in the distribution of precariousness. And secondly, precarity tends to imply a universal condition of ‘temporal poverty’ where all social experience appears dominated by the frenetic demands of a speeded-up, unstable and fragmented social world. In this article, we show how these two omissions are interlinked and prevent a more nuanced understanding of time in artistic labour. Drawing from findings from empirical research with working visual artists in the Midlands of the UK, we propose three schematic ways of thinking about the organisation of time and temporality in routine artistic practice. We name these three temporal contexts ‘the artistic career’; ‘the time of making art’ and ‘the temporality of the work’. By researching how artists might be differently positioned in relation to time, we suggest, we not only obtain a more precise understanding of how professional artists’ lives are organised, managed and lived, but also a more distinct understanding of precarity itself.

Optimal functionalization of a molecular electrocatalyst for hydride transfer

Optimization of hydride transfer (HT) catalysts to enhance rates and selectivities of (photo)electroreduction reactions could be a crucial component of a sustainable chemical industry. Here, we analyze how ring functionalization of the adsorbed transient intermediate 2-pyridinide (2-PyH−*)—predicted to form in situ from pyridine (Py) in acidified water at a cathode surface and to be the key to selective CO2 photoelectroreduction on p-GaP—may enhance catalytic activity. Earlier studies revealed that 2-PyH−*’s instability results from a protonation side reaction producing adsorbed dihydropyridine (DHP*), which is relatively HT-inactive. Reducing the electron density on 2-PyH−* could limit this protonation, with the trade-off that it may become less active for HT from 2-PyH−*–R to CO2. We explore here how Py functionalization affects the electron distribution and in turn tunes the catalytic performance of 2-PyH−*. We indeed find that electron-withdrawing groups could enhance the stability of 2-PyH−* by reducing its electron density on the ring. Furthermore, we find that the change in the number of electrons on the substituting group of the hydride donor is a good descriptor for both the stability against protonation and the magnitude of the HT barrier. We predict that –CH2–CH2F is the best candidate substituent, as it significantly improves the stability of 2-PyH−* with only a small increase in HT barrier. –CH=CH2 and –CH2F also could be promising, although they require further investigation due to a larger HT-barrier increase.

Traffic Flow Classification using a Video Descriptor and a Convolutional Neural Network

Traffic congestion is a significant problem in urban cities and affects economic, health, and social questions. Although many works have been published in the last years to traffic applications based on video data, different techniques of computer vision can be explored in this area. In this work, we proposed a method for traffic flow classification using StarRGB and Convolutional Neural Networks (CNN). The StarRGB describes a global representation of the traffic video into a colored image based on motion elements in the scene. Then, the generated image passed as input to a pre-trained CNN to extract the features and classify the traffic video activity in three classes: LIGHT, MEDIUM, and HEAVY. In our experiments using a traffic video database, the proposed method reached an accuracy of 96.47%. Also, the results suggest that StarRGB is a good descriptor for traffic video applications.

Deep insights into the exfoliation properties of MAX to MXenes and the hydrogen evolution performances of 2D MXenes

Surface terminated O-p orbital center εp, could be used as a good descriptor for HER of MXenes.