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The syntheses of Ni-poor (NCM111, LiNi1/3Co1/3Mn1/3O2) and Ni-rich (NCM811 LiNi0.8Co0.1Mn0.1O2) lithium transition-metal oxides (space group R3̅m) from hydroxide precursors (Ni1/3Co1/3Mn1/3(OH)2, Ni0.8Co0.1Mn0.1(OH)2) are investigated using in situsynchrotron powder diffraction and near-edge X-ray absorption fine structure spectroscopy. The development of the layered structure of these two cathode materials proceeds viatwo utterly different reaction mechanisms. While the synthesis of NCM811 involves a rock salt-type intermediate phase, NCM111 reveals a layered structure throughout the entire synthesis. Moreover, the necessity and the impact of a preannealing step and a high-temperature holding step are discussed.

Textbooks are an important aspect of students’ school lives and the representation of scientists in textbooks is a proxy for the representation of who can do science. This study investigated the names of scientists and other people mentioned in four commonly used textbooks in the three education systems in the UK and Republic of Ireland (England, Wales, and Northern Ireland using the A Level system; Scotland using the Curriculum for Excellence Highers system; Republic of Ireland using the Leaving Certificate system) and characterised them by gender. We found an overwhelming bias towards naming of famous men in three of the four textbooks (1 man and 0 women in the A Level textbook; 8 men and 0 women in the first, and 48 men and 2 women in the second Curriculum for Excellence textbooks, and 45 men and 1 woman in the Leaving Certificate). We subsequently analysed images and again found a dominance of images representing men in three of the four textbooks including only 4 women in a total of 68 images in the Leaving Certificate textbook. These images were analysed by role (scientist or not), and by activity according to UNESCO criteria. There was a tendency to show men in scientific and other occupational roles while women were less well represented in scientific roles and were pictured in domestic and buying activities. This work aims to raise awareness of these representations and prompt action for reform in line with UN Strategic Development goals.

X-ray characterization techniques are invaluable for probing material characteristics and properties, and have been instrumental in discoveries across materials research. However, there is a current lack of understanding of how X-ray-induced effects manifest in small molecular crystals. This is of particular concern as new X-ray sources with ever-increasing brilliance are developed. In this paper, systematic studies of X-ray–matter interactions are reported on two industrially important catalysts, [Ir(COD)Cl]2and [Rh(COD)Cl]2, exposed to radiation in X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) experiments. From these complementary techniques, changes to structure, chemical environments, and electronic structure are observed as a function of X-ray exposure, allowing comparisons of stability to be made between the two catalysts. Radiation dose is estimated using recent developments to the RADDOSE-3D software for small molecules and applied to powder XRD and XPS experiments. Further insights into the electronic structure of the catalysts and changes occurring as a result of the irradiation are drawn from density functional theory (DFT). The techniques combined here offer much needed insight into the X-ray-induced effects in transition-metal catalysts and, consequently, their intrinsic stabilities. There is enormous potential to extend the application of these methods to other small molecular systems of scientific or industrial relevance.

Mechanochemical synthesis has recently emerged as a scalable “green” approach for the preparation of MOFs, but current understanding of the underlying reaction mechanisms is limited. In this work, an investigation of the reaction pathway of the mechanochemical synthesis of MOF-74 from ZnO and 2,5-dihydroxyterephthalic acid (H4HDTA), using DMF as a liquid additive, is presented. The complex reaction pathway involves the formation of four short-lived intermediate phases, prior to the crystallization of MOF-74. The crystal structures of three of these intermediates have been determined using a combination of single-crystal and powder X-ray diffraction methods and are described here. The initial stages of the reaction are very fast, with a DMF solvate of H4HDTA forming after only 2 min of milling. This is followed by crystallization, after only 4 min of milling, of a triclinic one-dimensional coordination polymer, Zn(H2DHTA)(DMF)2(H2O)2, which converts into a monoclinic polymorph on additional milling. Highly crystalline MOF-74 appears after prolonged milling, for at least 70 min.

The lithium-exchanged form of a merlinoite zeolite (MER) with Si/Al = 4.2 (unit cell composition Li6.2Al6.2Si25.8O64) possesses a strongly contracted framework when dehydrated (the unit cell volume decreases by 12.9% from the hydrated “wide-pore” form to the dehydrated “narrow-pore” form). It shows cooperative adsorption behavior for CO2, leading to two-step isotherms with the second step at elevated pressure (>2.5 bar at 298 K). Partially exchanging Na and K cations to give single-phase Li,Na- and Li,K-MER materials reduces the pressure of this second adsorption step because the transition from narrow- to wide-pore forms upon CO2adsorption occurs at lower partial pressures compared to that in Li-MER: partial exchange with Cs does not reduce the pressure of this transition. Exsolution effects are also seen at K cation contents >2.2 per unit cell. The phase transitions proceed via intermediate structures by complex phase behavior rarely seen for zeolitic materials. The strongly distorted narrow-pore structures adopted upon dehydration give one-dimensional channel structures in which the percolation of CO2through the material requires cation migration from their locations in stesites. This is slow in Li3.4Cs2.8-MER where Cs cations occupy these critical stecavities in the channels, causing very slow adsorption kinetics. As the partial pressure of CO2increases, a threshold pressure is reached where cooperative adsorption and Cs cation migration occur and the wide-pore form results, with a three-dimensionally connected pore system, leading to a sharp increase in uptake. This is far in excess of the increase of unit cell volume because more of the pore space becomes accessible. Strong hysteretic effects occur upon desorption, leading to CO2encapsulation. CO2remaining within the material after repeated adsorption/desorption cycles without heated activation improves sorption kinetics and modifies the stepped isotherms.

Cadmium cyanide, Cd(CN)2, is a flexible coordination polymer best studied for its strong and isotropic negative thermal expansion (NTE) effect. Here we show that this NTE is actually X-ray-exposure dependent: Cd(CN)2contracts not only on heating but also on irradiation by X-rays. This behaviour contrasts that observed in other beam-sensitive materials, for which X-ray exposure drives lattice expansion. We call this effect ‘negative X-ray expansion’ (NXE) and suggest its origin involves an interaction between X-rays and cyanide ‘flips’; in particular, we rule out local heating as a possible mechanism. Irradiation also affects the nature of a low-temperature phase transition. Our analysis resolves discrepancies in NTE coefficients reported previously on the basis of X-ray diffraction measurements, and we establish the ‘true’ NTE behaviour of Cd(CN)2across the temperature range 150–750 K. The interplay between irradiation and mechanical response in Cd(CN)2highlights the potential for exploiting X-ray exposure in the design of functional materials.

By tuning the tolerance factor, t, of the Ruddlesden–Popper oxide Ca2MnO4through isovalent substitutions, we show that the uniaxial coefficient of linear thermal expansion (CLTE) of these systems can be systematically changed through large negative to positive values. High-resolution X-ray diffraction measurements show that the magnitude of uniaxial negative thermal expansion (NTE) increases as tdecreases across the stability window of the NTE phase. Transitions to phases with positive thermal expansion (PTE) are found to occur at both the high-tand low-tlimits of stability. First-principles calculations demonstrate that reducing tenhances the contribution to thermal expansion from the lowest frequency phonons, which have the characteristics of octahedral tilts and have negative mode Grüneisen parameter components along the NTE axis. By tuning tto the lower edge of the NTE phase stability window, we are hence able to maximize the amplitudes of these vibrations and thereby maximize NTE with a CLTE of −8.1 ppm/K at 125 K. We also illustrate, at the other end of the phase diagram, that an enhancement in compliance of these materials associated with the rotational instability provides another mechanism by which NTE could be yet further enhanced in this and related systems.

Aromatic and heterocyclic molecules which form electronically complementary π–π stacked complexes have recently found extensive application in functional materials, molecular machines, and stimuli-responsive supramolecular polymers. Here we describe the design and synthesis of model compounds that self-assemble through complementary stacking motifs, paralleling those postulated to exist in high-molecular weight, healable, supramolecular polymer systems. Complexation studies using 1H NMR and UV–vis spectroscopy indicated formation of a complementary complex between a π-electron rich dipyrenyl tweezer-motif and a tweezer-like, π-electron deficient bis-diimide. The binding stoichiometry in solution between the chain-folding diimide and the pyrenyl derivative was equimolar with respect to the two binding motifs, and the resulting association constant was measured at Ka= 1200 ± 90 M–1. Single crystal X-ray analysis of this “tweezer–tweezer” complex showed a low-energy conformation of the triethylenedioxy linker within the bis-diimide chain-fold. Interplanar separations of 3.4–3.5 Å were found within the π-stacks, and supporting hydrogen bonds between pyrenyl amide NH groups and diimide carbonyl oxygens were identified.

Pregnancy loss prior to fetal viability is a common experience for women worldwide – 1 in 4 pregnancies end in miscarriage. Increased recognition of the impact of such loss has put the issue of statutory leave in this context on the policy and legislative agenda in an increasing number of jurisdictions. This article seeks to help inform these debates by presenting the findings of a comparative study of jurisdictions which have introduced such leave. From this, the article identifies two main approaches: leave based on the sick leave model and leave based on the compassionate leave model. The article argues that both models have strengths and limitations. What works in each individual jurisdiction will depend, among other factors, on the way in which the jurisdiction in question addresses the issue of leave more broadly. However, regardless of the model adopted, the article argues that some form of statutory leave for miscarriage and other pregnancy loss should be introduced on the basis that such leave serves to reinforce the equality agenda, provides a chance for care and recovery following pregnancy loss, and serves an important expressive and educative goal in ensuring better understanding of the impact of pregnancy loss on those who experience such loss.

This paper characterizes the actual science performance of the James Webb Space Telescope (JWST), as determined from the six month commissioning period. We summarize the performance of the spacecraft, telescope, science instruments, and ground system, with an emphasis on differences from pre-launch expectations. Commissioning has made clear that JWST is fully capable of achieving the discoveries for which it was built. Moreover, almost across the board, the science performance of JWST is better than expected; in most cases, JWST will go deeper faster than expected. The telescope and instrument suite have demonstrated the sensitivity, stability, image quality, and spectral range that are necessary to transform our understanding of the cosmos through observations spanning from near-earth asteroids to the most distant galaxies.

In this work, we report the mixing behavior of a series of normal alkanes adsorbed on the surface of hexagonal boron nitride (h-BN) using X-ray powder diffraction. We have investigated a range of simple binary mixtures which are indicative of a rich phase behavior with examples of complete mixing, partial mixing, and phase separation. On graphite surfaces, the mixing behavior is strongly influenced by the structure of the pure components; the odd–even effect seen in the pure structures, which favors either a “herringbone” or a “parallel” structure, influences the miscibility of alkanes within the monolayer. On h-BN, a more complex phase behavior is observed with partial mixing or phase separation depending upon the exact composition of the monolayer. In particular, we see improved miscibility for certain mixtures containing n-decane which we associate with the fact that pure n-decane has been observed with both herringbone and parallel structures on h-BN. This difference between these two very similar substrates is a sensitive indicator of the subtle interplay between surface–molecule and molecule–molecule interactions that govern the phase behavior of these systems.

The adsorption of CO2on zeolite Li-Rho (unit cell composition Li9.8Al9.8Si38.2O96) has been investigated by the measurement of adsorption isotherms (273–300 K), breakthrough curves with a CO2/CH4/He mixture (308 K), and in situsynchrotron X-ray powder diffraction in CO2(298 K). The Rho framework distorts when in the Li-form to give a shape selective adsorbent for CO2over CH4, although breakthrough curves reveal diffusional limitations. In situsynchrotron powder XRD follows the expansion of the Li-Rho unit cell upon adsorption, which remains single phase to a CO2pressure of ca. 0.6 bar. Partial cation exchange of Li-Rho by Na+or Cs+gives two series of M,Li-Rho zeolites (M = Na, Cs). Where the occupancy of window sites (8R, D8R) between ltacages is less than 50%, hysteresis is not observed in CO2isotherms at 298 K. For Cs1.8Li8-Rho, which has a larger unit cell and a wider window than zeolite Li-Rho due to the presence of large Cs+cations in double 8-ring sites, breakthrough curves indicate faster CO2diffusion without significant loss of selectivity. We propose this control of adsorption kinetics of the flexible zeolite Rho via modification of cation content as a mechanism for cation controlled molecular sieving.

The metal–organic framework MIL-53(Al) is characterized by a distinct reversible structural transition between a narrow pore (NP) and a large pore (LP) state, resulting in expansion or contraction of this three-dimensional porous framework also called breathing. This transition is studied for vanadium-doped MIL-53(Al), induced by temperature (T) using in situelectron paramagnetic resonance (EPR) and X-ray diffraction (XRD) in air and in vacuum. The EPR active VIVO molecular ions are used as local probes to detect the NP to LP transitions. The EPR spectra of VIVO embedded in the NP and LP MIL-53(Al) states are clearly distinguishable. The temperature-dependent EPR and XRD data can consistently be interpreted in terms of T-ranges in the experiments where one of the states is predominantly present and a narrow T-range in which the two states coexist. In addition the XRD data indicate that the NP state undergoes a transition to a metastable state characterized by different lattice parameters than the NP state at room temperature, before the transition to the LP state occurs. The EPR spectra, however, show that only in the LP state the VIVO ions can exhibit an interaction with paramagnetic O2molecules from air.

In 2013, the New York Organization of Nurse Executives and Leaders (NYONEL) sponsored a contest to systematically gather testimonials from direct care providers that would further support the concept that education to the bachelor of science (BS) degree makes a difference in the clinical practice of individuals already licensed as registered nurses (RNs). This initiative was catalyzed by nursing leaders in New York State (NYS) who were members of the Coalition for the Advancement of Nursing Education, leading the efforts that support legislation that would require a new registered nurse to obtain a bachelor's degree in nursing within 10 years of licensure. [ABSTRACT FROM AUTHOR]

Claire Murray ponders on the attraction benzene — a small, seemingly simple molecule — has long exerted on scientists, some of the insights gained through its exploration, and the varied applications found for this hexagonal ring and its derivatives.

A novel PdIr/C supported alloy nanoparticle catalyst has been developed for use in the hydrogen oxidation reaction (HOR) at the anode of an Alkaline Anion Exchange Membrane (AAEM) fuel cell. The catalyst has been characterized using Transmission Electron Microscopy (TEM), Energy Dispersive X-ray Spectroscopy (EDX) and Synchrotron X-ray Powder Diffraction (SXPD). Electrochemical testing suggests it has a comparable activity for HOR as Pt/C and is a good candidate for use on the anode of an AAEM fuel cell.

The article explores the limitations of legislative reform in the development of a rights-based model of mental health law. It mentions that the European Convention on Human Rights (ECHR) acts as the stimulus behind the development of rights-based mental health law in Ireland. It informs about commencement of the Mental Health Act 2001 for monitoring of mental health legislation and mental health rights protection.

A focused library of potential hydrogelators each containing two substituted aromatic residues separated by a urea or thiourea linkage have been synthesised and characterized. Six of these novel compounds are highly efficient hydrogelators, forming gels in aqueous solution at low concentrations (0.03–0.60 wt %). Gels were formed through a pH switching methodology, by acidification of a basic solution (pH 14 to ≈4) either by addition of HCl or via the slow hydrolysis of glucono‐δ‐lactone. Frequently, gelation was accompanied by a dramatic switch in the absorption spectra of the gelators, resulting in a significant change in colour, typically from a vibrant orange to pale yellow. Each of the gels was capable of sequestering significant quantities of the aromatic cationic dye, methylene blue, from aqueous solution (up to 1.02 g of dye per gram of dry gelator). Cryo‐transmission electron microscopy of two of the gels revealed an extensive network of high aspect ratio fibers. The structure of the fibers altered dramatically upon addition of 20 wt % of the dye, resulting in aggregation and significant shortening of the fibrils. This study demonstrates the feasibility for these novel gels finding application as inexpensive and effective water purification platforms.

The article presents information on personnel changes within the South Carolina nursing industry including information on Peggy Hewlett, PhD, RN, FAAN, the dean of the University of South Carolina College of Nursing, Patrick Hickey of the University of South Carolina and registered nurse Gail Stuart.

The article focuses on the issue of reinforcing paternalistic judicial approach within mental health law in Ireland. It examines the decisions of the courts on EH v St. Vincent's Hospital and Others and on SM v The Mental Health Commission. It discusses the Mental Health Act (MHA) 2001, which stresses the importance of protecting the rights of people with mental disorders. The role of the judiciary in the rights-based model of mental health law is explored.

Bond formation and breakage is crucial upon energy storage in lithium transition metal oxides (LiMeO2, Me= Ni, Co, Mn), i.e., the conventional cathode materials in Li ion batteries. Near-edge X-ray absorption finestructure spectroscopy (NEXAFS) of the MeL and O K edge performed upon the first discharge of LiNixCo(1−x)/2Mn(1−x)/2O2(x= 0.33: NCM111, x= 0.6: NCM622, x= 0.8: NCM811) in combination with charge transfer multiplet (CTM) calculations provide unambiguous evidence that redox reactions in NCMs proceed viaa reversible oxidation of Ni associated with the formation of covalent bonds to O neighbors, and not, as widely assumed, via pure cationic or more recently discussed, pure anionic redox processes. Correlating these electronic changes with crystallographic data using operandosynchrotron X-ray powder diffraction (SXPD) shows that the amount of ionic Ni limits the reversible capacity— at states of charge where all ionic Ni is oxidized (above 155 mAh g−1), the lattice parameters collapse, and irreversible reactions are observed. Yet the covalence of the Ni–O bonds also triggers the electronic structure and thus the operation potential of the cathodes.

The clinical efficacy of two intensive treatment packages (one including the new antipsychotic risperidone and the other not doing so) was compared with that of standard management in 43 patients with long-standing treatment-resistant schizophrenia. Significant differences between the groups in terms of total positive or total negative symptoms were not demonstrated, but the pattern of change between the treatment groups differed, so that benefit in positive symptomatology was seen in both intensive treatment groups and in negative symptomatology in the intensive treatment/risperidone group and the standard group. Changes in general psychopathology were most marked in the risperidone group and were compatible with a relatively non-sedative profile. Using the Disability Assessment Schedule, substantial significant advantages for the intensive treatment groups were found.

The contributions of women to the development of the periodic table have long been overlooked. Claire Murray relates how the recent ‘Setting their table’ conference set out to highlight their prominent role in element discovery and use.

Small pore zeolites that show framework flexibility, such as merlinoite (topology type MER), possess a high potential for the selective adsorption of small gas molecules including CO2. The CO2adsorption properties of Na-, K-, and Cs-exchanged forms of a merlinoite zeolite with Si/Al = 4.2 have been measured at 298 K, and in situPXRD was used to follow their structural response to dehydration and CO2uptake. The Na- and Cs-forms convert from a wide-pore to a narrow-pore form upon dehydration, while the K-form remains in the wide-pore form. The Na- and Cs-forms exhibit stepped CO2adsorption isotherms, consistent with breathing behavior and expansion from narrow- to wide-pore phases, while K6.2-MER remains in the wide-pore structure throughout. Synchrotron PXRD of the K- and Cs-forms reveals the effects of CO2adsorption on the cation site distributions and the framework configuration. All cation forms of MER (4.2) show enhanced adsorption kinetics for Ar compared to those with lower Si/Al, and the wide-pore structure of K6.2-MER (4.2) shows particularly rapid sorption for both Ar and CO2. Breakthrough curves over K6.2-MER (4.2) demonstrate good separation of CO2from CH4in flowing CO2/CH4mixtures, even in pelletized form with an alumina binder.

We present a comprehensive structural and magnetic characterization of the barlowite family of S= 1/2 kagomé magnets, Cu4(OH)6FX, where X = Cl, Br, or I. Through high-resolution synchrotron X-ray and neutron powder diffraction measurements, we reveal two sources of structural complexity within this family of materials, namely, compositional disorder of the halide species that occupy sites in between the kagomé layers and the positional disorder of the interlayer Cu2+ions that persists well into the Pnmastructural ground state. We demonstrate that understanding these inherent structural disorders is key as they correlate with the degree of partial order in the magnetic ground states of these quantum frustrated magnets.

A novel PdIr/C supported alloy nanoparticle catalyst has been developed for use in the hydrogen oxidation reaction (HOR) at the anode of an Alkaline Anion Exchange Membrane (AAEM) fuel cell. The catalyst has been characterized using Transmission Electron Microscopy (TEM), Energy Dispersive X-ray Spectroscopy (EDX) and Synchrotron X-ray Powder Diffraction (SXPD). Electrochemical testing suggests it has a comparable activity for HOR as Pt/C and is a good candidate for use on the anode of an AAEM fuel cell.

A novel PdIr/C supported alloy nanoparticle catalyst has been developed for use in the hydrogen oxidation reaction (HOR) at the anode of an Alkaline Anion Exchange Membrane (AAEM) fuel cell. The catalyst has been characterised using Transmission Electron Microscopy (TEM), Energy Dispersive X-ray Spectroscopy (EDX) and Synchrotron X-ray Powder Diffraction (SXPD). Electrochemical testing suggests it has a comparable activity for HOR as Pt/C and is a good candidate for use on the anode of an AAEM fuel cell.