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In recent years, evidence has emerged that actinide (An) uptake at the enhanced actinide removal plant (EARP) at the UK's Sellafield nuclear site occurs via An interactions with an α-Fe13 Keggin molecular cluster during ferrihydrite formation. We here study theoretically the substitution of aquo complexes of the actinides Th–Pu onto a Na-decorated α-Fe13 Keggin cluster using DFT at the PBE0 level. The optimised Pu–O and Pu–Fe distances are in good agreement with experiment and Na/An substitutions are significantly favourable energetically, becoming more so across the early 5f series, with the smallest and largest ΔrG° being for Th and Pu at −335.7 kJ mol−1 and −396.0 kJ mol−1 respectively. There is strong correlation between the substitution reaction energy and the ionic radii of the actinides (Δrε0R2 = 0.97 and ΔrG° R2 = 0.91), suggesting that the principal An-Keggin binding mode is ionic. Notwithstanding this result, Mulliken and natural population analyses reveal that covalency increases from Th–Pu in these systems, supported by analysis of the occupied Kohn–Sham molecular orbitals where enhanced An(5f)–O(2p) overlap is observed in the Np and Pu systems. By contrast, quantum theory of atoms in molecules analysis shows that U-Keggin binding is the most covalent among the five actinides, in keeping with previous studies. [ABSTRACT FROM AUTHOR]

This study examines the feasibility of using hydrogen as a clean energy source for residential consumers in the UK through a low-carbon energy hub. Two cases were compared: a solid oxide fuel cell (SOFC) integrated combined heat and power (CHP) system fuelled by natural gas and hydrogen; and a SOFC-heat pump (HP) integrated CHP system fuelled by natural gas and hydrogen. The study used the actual electricity and heating demands of a UK cluster to model the CHP systems. The results indicate that the SOFC-based CHP system with hydrogen as fuel is more energy-efficient than the natural gas-fuelled system, with energetic efficiencies of 92.12% and 66.98%, respectively. The study also found that the system incorporating a heat pump is more economically viable, regardless of the fuel source, with the hydrogen-powered system equipped with a heat pump having a levelised cost of energy (LCOE) of 0.2984 £ per kW h. The study also evaluated the environmental impact of the natural gas-powered SOFC and SOFC-HP systems, with estimated levelised CO2 emissions of 0.308 kg per kW h and 0.213 kg per kW h, respectively. The study's findings provide insights into the potential of hydrogen as a cleaner energy source for residential consumers in the UK and highlight the importance of exploring low-carbon energy alternatives. [ABSTRACT FROM AUTHOR]

Background: Metabolite profiling of blood by nuclear magnetic resonance (NMR) is invaluable to clinical biomarker discovery. To ensure robustness, biomarkers require validation in large cohorts and across multiple centres. However, collection procedures are known to impact on the stability of biofluids that may, in turn, degrade biomarker signals. We trialled three blood collection tubes with the aim of solving technical challenges due to preanalytical variation in blood metabolite levels that are common in cohort studies. Methods: We first investigated global NMR-based metabolite variability between biobanks, including the large-scale UK Biobank and TwinsUK biobank of the general UK population, and more targeted biobanks derived from multicentre clinical trials relating to inflammatory bowel disease. We then compared the blood metabolome of 12 healthy adult volunteers when collected into either sodium fluoride/potassium oxalate, lithium heparin, or serum blood tubes using different pre-processing parameters. Results: Preanalytical variation in the method of blood collection strongly influences metabolite composition within and between biobanks. This variability can largely be attributed to glucose and lactate. In the healthy control cohort, the fluoride oxalate collection tube prevented fluctuation in glucose and lactate levels for 24 hours at either 4 °C or room temperature (20 °C). Conclusions: Blood collection into a fluoride oxalate collection tube appears to preserve the blood metabolome with delayed processing up to 24 hours at 4 °C. This method may be considered as an alternative when rapid processing is not feasible. [ABSTRACT FROM AUTHOR]

Optimal oncological results and patient outcomes are achieved in surgery for early breast cancer with breast conserving surgery (BCS) where this is appropriate. A limitation of BCS occurs when cancer is present at, or close, to the resection margin – termed a 'positive' margin – and re-excision is recommended to reduce recurrence rate. This is occurs in 17% of BCS in the UK and there is therefore a critical need for a way to assess margin status intraoperatively to ensure complete excision with adequate margins at the first operation. This study presents the potential of high wavenumber (HWN) Raman spectroscopy to address this. Freshly excised specimens from thirty patients undergoing surgery for breast cancer were measured using a surface Raman probe, and a multivariate classification model to predict normal versus tumour was developed from the data. This model achieved 77.1% sensitivity and 90.8% specificity following leave one patient out cross validation, with the defining features being differences in water content and lipid versus protein content. This demonstrates the feasibility of HWN Raman spectroscopy to facilitate future intraoperative margin assessment at specific locations. Clinical utility of the approach will require further research. [ABSTRACT FROM AUTHOR]

Over the past few decades, there have been increasing global efforts to limit or ban the use of animals for testing cosmetic products. This ambition has been at the heart of international endeavours to develop new in vitro and animal-free approaches for assessing the safety of cosmetics. While several of these new approach methodologies (NAMs) have been approved for assessing different toxicological endpoints in the UK and across the EU, there remains an absence of animal-free methods for screening for dermal absorption; a measure that assesses the degree to which chemical substances can become systemically available through contact with human skin. Here, we identify some of the major technical barriers that have impacted regulatory recognition of an in vitro skin model for this purpose and propose how these could be overcome on-chip using artificial cells engineered from the bottom-up. As part of our future perspective, we suggest how this could be realised using a digital biomanufacturing pipeline that connects the design, microfluidic generation and 3D printing of artificial cells into user-crafted synthetic tissues. We highlight milestone achievements towards this goal, identify future challenges, and suggest how the ability to engineer animal-free skin models could have significant long-term consequences for dermal absorption screening, as well as for other applications. [ABSTRACT FROM AUTHOR]

In this paper, a novel sunlight activable photocatalyst system based on the synergistic effect between a double Z-scheme g-C3N4–WO3–Bi2WO6 nanocomposite and long-lasting phosphorescent SrAl2O4:Eu2+,Dy3+ nanoparticles has been designed, synthesized and successfully applied for the removal of environmental pollutants. It is especially suitable for removing dye pollutants under cloudy weather similar to the conditions in the United Kingdom and Iranian north provinces. The developed photocatalyst system in this work is based on the following important factors; the first factor is applying the double z-scheme structure of the g-C3N4–WO3–Bi2WO6 photocatalyst to prevent fast electron–hole recombination and hence, enhance the photocatalytic efficiency of the proposed system. The second factor is applying long-lasting phosphorescent SrAl2O4 nanoparticles in the photocatalyst composition and hence, enhancing the population of the excited electrons on the photocatalyst surface. The emitted photons from SrAl2O4 nanoparticles are absorbed by the g-C3N4–WO3–Bi2WO6 photocatalyst particles, increasing the photo absorption efficiency of the photocatalyst. This effect enhances the population of the excited electrons on the photocatalyst surface, increasing the photocatalytic reaction speed. In addition, applying phosphorescent SrAl2O4 nanoparticles also retains the photocatalytic activity of the photocatalyst during the night or when the light sources are off, because the phosphorescence of these nanoparticles can last up to 10 hours. These nanoparticles play the role of tiny lamps for excitation of the photocatalyst particles during the night or during cloudy weather. The proposed system was able to remove up to 98% of the environmental pollutants such as dyes in less than 20 min. In addition, its advantages for removing dye pollutants under simulated cloudy weather were confirmed. [ABSTRACT FROM AUTHOR]

This Faraday Discussion was held on March 25–27th, 2019 at Murray Edwards College, Cambridge, UK and was attended by 160 delegates from over 20 countries. The attendees represented the cross-disciplinary nature of the field, with biologists, engineers, material scientists, theoreticians and experimental chemists of all experience levels coming together to discuss the state of the art. The meeting captured how rapidly the field of artificial photosynthesis has progressed in a short time and highlighted how far we still have to go. In this conference report, the topics of discussion will be outlined with a brief description of the papers presented and a summary of the conference events. [ABSTRACT FROM AUTHOR]

The 300th Faraday discussion on hot electron processes in plasmonics and catalysis brought together a wide spectrum of delegates from across the globe. Scientists from across multiple disciplines, with a broad spectrum of experience and expertise, joined together in hope of identifying and answering the latest problems within the ever growing hot electron science community. In this paper we present a brief overview of the themes and topics presented at this meeting, highlighting the major findings of each presentation. [ABSTRACT FROM AUTHOR]

Elucidations on the structure–activity correlations of non-Pt coordination polymer (CP)-based photocatalysts are highly significant for both the enhancement in catalytic activity and large-scale industrial applications of sustainable hydrogen from water splitting. Herein, three isostructural [Cu(HL)2(R-BDC)]n (denoted as Cu-CP-R, HL = 4′-(4-hydroxyphenyl)-4,2′:6′,4′′-terpyridine, R-BDC = 2-R-1,4-benzenedicarboxylate, R = NO2, OH and Br) CPs were solvothermally synthesized by varying the substituents attached to benzenedicarboxylate, which together with two previously reported analogues (R = NH2 and H) were used as photocatalysts to systematically explore the substitution effect on the hydrogen evolution activity. These five CPs feature isomorphic layered motifs with axially elongated CuII octahedra extended alternately by ditopic HL and R-BDC2− connectors, in which R behaves structurally as a non-coordinate group. The hydrogen production rate over the Cu-CP-R photocatalysts increased from 0.21 to 2.34 mmol g−1 h−1, which followed the order of –NH2 > –NO2 > –H > –OH > –Br. Furthermore, the combined experimental and theoretical investigations reveal that the free R moiety significantly dominates the photocatalytic activity by shifting the d states of the CuII ion towards the Fermi level, controlling the potential of the conduction band and quickening the charge transfer ability. These important findings can provide informative hints for the design of high-performance, earth-abundant non-noble metal CP-based semi-conductive photocatalysts. [ABSTRACT FROM AUTHOR]

In this work, neutron diffraction (ND) and neutron resonance transmission imaging (NRTI) are applied for the material characterization of composite artefacts, two bimetallic sword fragments from ancient China, in order to highlight the presence and distribution of phases and elements in the objects. The investigation was carried out at the INES beamline, a time-of-flight powder diffractometer operating at the ISIS neutron and muon source in the UK. ND was applied to identify and quantify crystalline phases, while NRTI, by means of a position sensitive n-GEM based neutron detector, provided us with the distribution of different elements in the objects. NRTI demonstrates the possibility of enhancing several elements (e.g. Fe, Cu, Ag, Sn, Sb, As, Co, Cr, In, and Mn) in neutron transmission images, achieving a spatial resolution of about 1.6 mm. Elemental mapping was performed by selecting some of the most intense neutron resonances (up to several keV) in the absorption spectra. [ABSTRACT FROM AUTHOR]

Over a third of brain tumour patients visit their general practitioner more than five times prior to diagnosis in the UK, leading to 62% of patients being diagnosed as emergency presentations. Unfortunately, symptoms are non-specific to brain tumours, and the majority of these patients complain of headaches on multiple occasions before being referred to a neurologist. As there are currently no methods in place for the early detection of brain cancer, the affected patients' average life expectancy is reduced by 20 years. These statistics indicate that the current pathway is ineffective, and there is a vast need for a rapid diagnostic test. Attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy is sensitive to the hallmarks of cancer, as it analyses the full range of macromolecular classes. The combination of serum spectroscopy and advanced data analysis has previously been shown to rapidly and objectively distinguish brain tumour severity. Recently, a novel high-throughput ATR accessory has been developed, which could be cost-effective to the National Health Service in the UK, and valuable for clinical translation. In this study, 765 blood serum samples have been collected from healthy controls and patients diagnosed with various types of brain cancer, contributing to one of the largest spectroscopic studies to date. Three robust machine learning techniques – random forest, partial least squares-discriminant analysis and support vector machine – have all provided promising results. The novel high-throughput technology has been validated by separating brain cancer and non-cancer with balanced accuracies of 90% which is comparable to the traditional fixed diamond crystal methodology. Furthermore, the differentiation of brain tumour type could be useful for neurologists, as some are difficult to distinguish through medical imaging alone. For example, the highly aggressive glioblastoma multiforme and primary cerebral lymphoma can appear similar on magnetic resonance imaging (MRI) scans, thus are often misdiagnosed. Here, we report the ability of infrared spectroscopy to distinguish between glioblastoma and lymphoma patients, at a sensitivity and specificity of 90.1% and 86.3%, respectively. A reliable serum diagnostic test could avoid the need for surgery and speed up time to definitive chemotherapy and radiotherapy. [ABSTRACT FROM AUTHOR]

The 2021 Faraday Discussion on reaction mechanisms in catalysis attracted over a hundred delegates from around the world. Notwithstanding the challenges we faced in 2020, the online platform brought together leading scientists passionate about understanding the mechanisms of catalysed reactions. The meeting showed the great shape of the field and proved the ability of the community to face global challenges, and to be adaptive, flexible, and responsive. [ABSTRACT FROM AUTHOR]

The article offers information on the history of inductively coupled plasma atomic emission spectral analysis. S. Greenfield was the first person to apply an inductively coupled plasma source produced by a high power generator for analytical purposes at the company Albright & Wilson in Great Britain.

A method for ultra-trace determination of Se and Te in coal by inductively coupled plasma mass spectrometry (ICP-MS) was developed. Samples (up to 500 mg) were prepared by microwave-induced combustion (MIC) in a closed system pressurized with 20 bar of oxygen. Inorganic acids or their mixtures were evaluated as absorbing solution. Using HNO3 + HCl (1 + 1), results obtained for Se and Te after sample preparation by MIC agreed with those obtained by reference methods, microwave-assisted wet digestion (MAWD) using concentrated HNO3 and HF, and solid sampling electrothermal vaporization inductively coupled plasma mass spectrometry (SS-ETV-ICP-MS), and also with a certified reference material of coal (NIST 1632c) for Se. Very low limits of quantification (LOQ) were obtained: 0.002 and 0.007 mg kg−1 for Se and Te, respectively. Major elements were determined in final solutions obtained by MAWD and MIC, and their concentration in solutions of MIC was negligible (<10 μg L−1), minimizing the risk of interference in ICP-MS analysis. The proposed method was applied to samples of coal from the United Kingdom, with a wide range of inorganic composition (from 3 to 41% ash content), showing its robustness and feasibility for routine analysis. Se concentration ranged from 0.291 to 11.5 mg kg−1, and Te was mainly found at ultra-trace levels (<0.007 to 0.11 mg kg−1). The proposed method presents several advantages over the reference methods, such as the use of a higher sample mass, low LOQs and, an important aspect, no need of using HF. [ABSTRACT FROM AUTHOR]

Selected ion flow tube mass spectrometry, SIFT-MS, a relatively new gas/vapour phase analytical method, is derived from the much earlier selected ion flow tube, SIFT, used for the study of gas phase ion-molecule reactions. Both the SIFT and SIFT-MS techniques were conceived and developed in the UK, the former at Birmingham University, the latter at Keele University along with the complementary flowing afterglow mass spectrometry, FA-MS, technique. The focus of this short review is largely to describe the origins, developments and, most importantly, the unique features of SIFT-MS as an analytical tool for ambient analysis and to indicate its growing use to analyse humid air, especially exhaled breath, its unique place as a on-line, real time analytical method and its growing use and applications as a non-invasive diagnostic in clinical diagnosis and therapeutic monitoring, principally within several UK universities and hospitals, and briefly in the wider world. A few case studies are outlined that show the potential of SIFT-MS and FA-MS in the detection and quantification of metabolites in exhaled breath as a step towards recognising pathophysiology indicative of disease and the presence of bacterial and fungal infection of the airways and lungs. Particular cases include the detection of Pseudomonas aeruginosa infection of the airways of patients with cystic fibrosis (SIFT-MS) and the measurement of total body water in patients with chronic kidney disease (FA-MS). The growing exploitation of SIFT-MS in other areas of research and commerce are briefly listed to show the wide utility of this unique UK-developed analytical method, and future prospects and developments are alluded to. [ABSTRACT FROM AUTHOR]

The article offers information on the periodical "New Journal of Chemistry" along with information for reader to apply for teacher training scholarship of Royal Society of Chemistry in Great Britain.