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Ferrocenyl diphosphine bridged diiron dithiolate complexes have been prepared and their redox properties investigated by CV and IR SEC supported by DFT calculations to give insight into their proton reduction and hydrogen oxidation activity.

Air and moisture stable diaryl dithiocarbamate salts, Ar2NCS2Li, result from addition of CS2 to Ar2NLi. They react cleanly to afford [Co(S2CNAr2)3] which decompose in amine solutions to give CoS2.

Ionic liquids are becoming increasingly popular for practical applications such as biomass processing and lithium-ion batteries. However, identifying ionic liquids with optimal properties for specific applications by trial and error is extremely inefficient since there are a vast number of potential candidate ions. Here we combine experimental and computational techniques to determine how the interplay of fluorination, flexibility and mass affects the transport properties of ionic liquids with the popular imide anion. We observe that fluorination and flexibility have a large impact on properties such as viscosity, whereas the influence of mass is negligible. Using targeted modifications, we show that conformational flexibility provides a significant contribution to the success of fluorination as a design element. Contrary to conventional wisdom, fluorination by itself is thus not a guarantor for beneficial properties such as low viscosity.

The reaction between differently substituted borasiloxanes and 2,5-bis(3-pyridylethynyl)thiophene provided the first example of luminescent borasiloxane-based chiral helices held together by N-B bonds. The starting building blocks and the helices were fully characterized, and the nature of the N-B bond rationalized by means of theoretical calculations.

In a data-driven economy, access to data is vital. So, what happens when data are not available due to disclosure issues or other restrictions? As Ioannis Kaloskampis, Chaitanya Joshi, Catrin Cheung, David Pugh and Louisa Nolan explain, in such situations it may still be possible to draw useful conclusions based on carefully manufactured data

Bardsey Island is located at the western end of the Llŷn Peninsula in northwestern Wales. Separated from the mainland by a channel that is some 3 km wide, it is surrounded by reversing tidal streams of up to 4 m s−1 during spring tides. These local hydrodynamic details and their consequences are unresolved by satellite altimetry and are not represented in regional tidal models. Here we look at the effects of the island on the strong tidal stream in terms of the budgets for tidal energy dissipation and the formation and shedding of eddies. We show, using local observations and a satellite-altimetry-constrained product (TPXO9), that the island has a large impact on the tidal stream and that even in this latest altimetry-constrained product the derived tidal stream is under-represented due to the island not being resolved. The effect of the island leads to an underestimate of the current speed in the TPXO9 data in the channel of up to a factor of 2.5, depending on the timing in the spring–neap cycle, and the average tidal energy resource is underestimated by a factor up to 14. The observed tidal amplitudes are higher at the mainland than at the island, and there is a detectable phase lag in the tide across the island; this effect is not seen in the TPXO9 data. The underestimate of the tide in the TPXO9 data has consequences for tidal dissipation and wake effect computation and shows that local observations are key to correctly estimating tidal energetics around small-scale coastal topography.

In this work we investigate the structure–property relationships in a series of alkylimidazolium ionic liquids with almost identical molecular weight. Using a combination of theoretical calculations and experimental measurements, we have shown that re-arranging the alkyl side chain or adding functional groups results in quite distinct features in the resultant ILs. The synthesised ILs, although structurally very similar, cover a wide spectrum of properties ranging from highly fluid, glass forming liquids to high melting point crystalline salts. Theoretical ab initio calculations provide insight on minimum energy orientations for the cations, which then are compared to experimental X-ray crystallography measurements to extract information on hydrogen bonding and to verify our understanding of the studied structures. Molecular dynamics simulations of the simplest (core) ionic liquids are used in order to help us interpret our experimental results and understand better why methylation of C2 position of the imidazolium ring results in ILs with such different properties compared to their non-methylated analogues.

The structure and molecular order in the thermotropic ionic liquid crystal (ILC), [choline][geranate(H)octanoate], an analogue of Choline And GEranate (CAGE), which has potential for use as a broad-spectrum antimicrobial and transdermal and oral delivery agent, were investigated by magic-angle spinning (MAS) nuclear magnetic resonance (NMR), polarizing optical microscopy, small-angle X-ray scattering (SAXS), and mass spectrometry. Mass spectrometry and the 1H NMR chemical shift reveal that CAGE-oct is a dynamic system, with metathesis (the exchange of interacting ions) and hydrogen exchange occurring between hydrogen-bonded/ionic complexes such as [(choline)(geranate)(H)(octanoate)], [(choline)(octanoate)2(H)], and [(choline)(geranate)2(H)]. These clusters, which are shown by mass spectrometry to be significantly more stable than expected for typical electrostatic ion clusters, involve hydrogen bonding between the carboxylic acid, carboxylate, and hydroxyl groups, with rapid hydrogen bond breaking and re-formation observed to average the 1H chemical shifts. The formation of a partial bilayer liquid crystal (LC) phase was identified by SAXS and polarizing optical microscopy at temperatures below ∼293 K. The occurrence of this transition close to room temperature could be utilized as a potential temperature-induced “switch” of the anisotropic properties for particular applications. The presence of an isotropic component of approximately 23% was observed to coexist with the LC phase, as detected by polarizing optical microscopy and quantified by both 1H–13C dipolar-chemical shift correlation (DIPSHIFT) and 1H double-quantum (DQ) MAS NMR experiments. At temperatures above the LC-to-isotropic transition, intermediate-range order (clustering of polar and nonpolar domains), a feature of many ILs, persists. Site-specific order parameters for the LC phase of CAGE-oct were obtained from the MAS NMR measurement of the partially averaged 13C–1H dipolar couplings (DCH) by cross-polarization (CP) build-up curves and DIPSHIFT experiments, and 1H–1H dipolar couplings (DHH) by double-quantum (DQ) build-up curves. The corresponding order parameters, SCH and SHH, are in the range 0–0.2 and are lower compared to those for smectic (i.e., layered) phases of conventional nonionic liquid crystals, resembling those of lamellar phases formed by lyotropic surfactant–solvent systems.\ud \ud

Sea level records have been obtained from a dozen tide gauges deployed around the Shetland Islands, and the high-frequency components of each record have been analysed to determine how the amplitudes and periods of seiches vary from place to place. We have found that seiches occur almost everywhere, although with different periods at different locations, and sometimes with amplitudes exceeding several decimetres. Spectral analysis shows that two or more modes of seiching are present at some sites. The study attempts to explain, with the help of a numerical model, why seiches with particular periods are observed at each location, and what forcings are responsible for them. In particular, we have revisited an earlier study of seiches on the east coast of Shetland by Cartwright and Young (Proc R Soc Lond A 338:111–128, 1974) and find no evidence to support the theory that they proposed for their generation. In addition, we have investigated how often and why the largest seiche events occur at Lerwick (with trough-to-crest wave heights of about 1 m), taking advantage of its long sea level record. Seiches (and other types of high-frequency sea level variability) are often ignored in studies of sea level changes and their coastal impacts. And yet they can be large enough to contribute significantly to the extreme sea levels that have major impacts on the coast. Therefore, our Shetland research serves as a case study of the need to have a fuller understanding of the climatology of seiches for the whole world coastline.

The behaviour of two molecular rotors, one charged – 3,3′-diethylthiacarbocyanine iodide (Cy3) and one neutral – 8-[4-decyloxyphenyl]-4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY-C10), have been studied in various ionic liquids. The fluorescent decay lifetime has been used to elucidate the structure of the immediate region around the rotor. The neutral BODIPY-C10 was found to prefer the non-polar alkyl chain environment, leading to two trends in the lifetime of the dye: one when it was fully partitioned into the non-polar domain, and one when it also sampled polar moieties. The positively charged Cy3 dye showed a complex relationship between the bulk viscosity of the ionic liquid and lifetime of the molecular rotor. This was attributed to a combination of polarity related spectral changes, changes in anion cages around the dye, and temperature dependent fluorescent lifetimes alongside the dependence of the rotor upon the viscosity.

Background The COVID-19 pandemic has disproportionately impacted homeless populations and service workers, especially within homeless shelter/hostel settings. To date, there have been few evidence syntheses examining outbreaks of COVID-19 among both homeless shelter residents and service workers and no critical review of infection control and prevention (IPAC) measures. This scoping review offers a much-needed synthesis of COVID-19 prevalence within homeless shelters and a review of pertinent IPAC measures. Methods We conducted a scoping review that aimed to synthesize academic and gray literature published from March 2020 to July 2021 pertaining to (1) the prevalence of COVID-19 among both residents and staff in homeless shelters and hostels in high-income countries and (2) COVID-19 IPAC strategies applied in these settings. Two reviewers independently screened the literature from several databases that included MEDLINE, PsycInfo, and the WHO’s COVID-19 Global Health Portal. The extracted data was mapped, categorized, and thematically discussed. Results Thematic analysis of 77 academic and gray literature documents revealed four key themes: (1) the demographics of COVID-19 in homeless shelters, (2) asymptomatic spread, (3) pre-existing vulnerability of people experiencing homelessness and shelters, and (4) the inconsistency and ineffectiveness of IPAC implementation. Conclusion This review offers a useful glimpse into the landscape of COVID-19 outbreaks in homeless shelters/hostels and the major contributing factors to these events. This review revealed that there is no clear indication of generally accepted IPAC standards for shelter residents and workers. This review also illustrated a great need for future research to establish IPAC best practices specifically for homeless shelter/hostel contexts. Finally, the findings from this review reaffirm that homelessness prevention is key to limiting disease outbreaks and the associated negative health outcomes in shelter populations. Limitations of this review included the temporal and database constraints of the search strategy, the exclusion of quality assessments of the literature, and the absence of investigation on the influence of emerging variants on public health policy. Systematic review registration This scoping review has not been registered on any database; the protocol is available on York University’s Institutional Repository https://dx.doi.org/10.25071/10315/38513.

Knowledge of regional changes in mean sea level, and local changes in tides are crucial to inform effective climate adaptation. An essential element of this is the availability of accurate observations of sea level. Sea level data in the Republic of Ireland, prior to the establishment of the National Tide Gauge Network in the mid- 2000s, is very limited but belies a wealth of historical data available in archival form. In this study, we digitize records located in Cork Harbour, Ireland from 1842 and show how short duration (6–8 weeks), high quality data, with a large interval (177 years) to the present, can accurately inform tidal and mean sea level changes. We consider error sources in detail and estimate that for M2 the accuracy of these historical measurements is 1 % and 2 minutes for amplitude and phase respectively, once adjustments for seasonal and nodal effects are made. Our mean sea level estimates are accurate to 2 cm level, once adjustments for atmospheric and seasonal effects are made. Our results show remarkable tidal stability with a 2 % change in the amplitude of the M2 component and 4-minute change in the phase over a period of 177 years; and a mean sea level rise of 40 cm in the Cork Harbour area since 1842, approximately in line with global mean sea level trends plus local glacial isostatic adjustment. More broadly, we show that with careful seasonal, nodal, and atmospheric corrections, together with good knowledge of benchmark provenance, these historic, survey- oriented data can accurately inform of sea level changes.

A comparison of chlorido-gallium functionalized alkoxides as precursors for aerosol-assisted chemical vapor deposition (AACVD) was carried out. Variable-temperature (VT)-NMR studies were used to probe the fluxional behavior of these alkoxides in solution, and hence their utility as precursors. The synthesis involved the initial isolation of the dimer [GaCl(NMe2)2]2 via a salt metathesis route from GaCl3 and 2 equiv of LiNMe2. This dimer was then reacted with 4 equiv of HOCH2CH2CH2NEt2, resulting in the formation of Ga[μ-(OCH2CH2CH2NEt2)2GaCl2]3 (1). Mass spectrometry and VT-NMR confirmed the oligomeric structure of 1. Tuning of the ligand properties, namely, the chain length and substituents on N, resulted in formation of the monomers [GaCl(OR)2] (R = CH2CH2NEt2, (2); CH2CH2CH2NMe2, (3)). VT-NMR studies, supported by density functional theory calculations, confirmed that the ligands in both 2 and 3 possess a hemilabile coordination to the gallium center, owing to either a shorter carbon backbone (2) or less steric hindrance (3). Both 2 and 3 were selected for use as precursors for AACVD: deposition at 450 °C gave thin films of amorphous Ga2O3, which were subsequently annealed at 1000 °C to afford crystalline Ga2O3 material. The films were fully characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, UV–visible spectroscopy, and energy dispersive X-ray analysis., A comparison of chlorido-gallium functionalized alkoxides for use as precursors toward gallium oxide (Ga2O3) via aerosol-assisted chemical vapor deposition was carried out. Variable-temperature NMR studies were used to probe the fluxionality of these alkoxides in solution, combined with computational modeling of their dynamic behavior and hence their utility as precursors. Thin films of gallium oxide were deposited, and full characterization of the films was carried out.

The COVID-19 pandemic has disproportionately impacted people experiencing homelessness. Homeless shelters and hostels, as congregate living spaces for residents with many health vulnerabilities, are highly susceptible to outbreaks of COVID-19. A synthesis of the research-to-date can inform evidence-based practices for infection, prevention, and control strategies at these sites to reduce the prevalence of COVID-19 among both shelter/hostel residents and staff. Methods: A scoping review in accordance with Arksey and O’Malley’s framework will be conducted to identify literature reporting COVID-19 positivity rates among homeless shelter and hostel residents and staff, as well as infection control strategies to prevent outbreaks in these facilities. The focus will be on literature produced in high-income countries. Nine academic literature databases and 11 grey literature databases will be searched for literature from March 2020 to July 2021. Literature screening will be completed by two reviewers and facilitated by Covidence, a systematic review management platform. A third reviewer will be engaged to resolve disagreements and facilitate consensus. A narrative summary of the major themes identified in the literature, numerical counts of relevant data including the COVID-19 positivity rates, and recommendations for different infection control approaches will be produced. Discussion: The synthesis of the research generated on COVID-19 prevalence and prevention in homeless shelters and hostels will assist in establishing best practices to prevent the spread of COVID-19 and other airborne diseases at these facilities in high-income countries while identifying next steps to expand the existing evidence base.

A tetracarboxylic acid with a methyl-substituted siloxane core (L-H4) has been prepared and applied in the construction of water stable MOFs with low water affinity. L-H4 itself crystallizes as an interpenetrated 3D hydrogen-bonded network. Reaction of L-H4 with ZrIV/HfIV gave IMP-32-Zr/Hf – both 3D MOFs of scu topology.

The identification of specific design concepts for the in silico design of ionic liquids (ILs) has been accomplished using theoretical methods. Molecular building blocks, such as interchangeable functional groups, are used to design a priori new ILs which have subsequently been experimentally investigated. The conformational design concepts are developed by separately and systematically changing the central (imide), bridging (sulfonyl) and end (trifluoromethyl) group of the bis(trifluoromethanesulfonyl)imide [N(Tf)2]− anion and examining the resultant potential energy surfaces. It is shown that these design concepts can be used to tune separately the minimum energy geometry, transition state barrier height and relative stability of different conformers. The insights obtained have been used to design two novel anions for ILs, trifluoroacetyl(methylsulfonyl)imide [N(Ms)(TFA)]− and acetyl(trifluoromethanesulfonyl)imide [N(Tf)(Ac)]−. The computationally predicted structures show excellent agreement with experimental structures obtained from X-ray crystallography. [C4C1im][N(Tf)(Ac)] and [C4C1im][N(Ms)(TFA)] ILs have been synthesised and ion diffusion coefficients examined using pulsed field gradient stimulated echo NMR spectroscopy. Significantly increased diffusion was observed for the more flexible [N(Tf)(Ac)]− compared with the more rigid [N(Ms)(TFA)]− analogue. Furthermore, a pronounced impact on the fluidity was observed. The viscosity of the IL with the rigid anion was found to be twice as high as the viscosity of the IL with the flexible anion. The design concepts presented in this work will enable researchers in academia and industry to tailor anions to provide ILs with specific desired properties.

The primary goal of the project is to design a hydraulic disk brake system for mountain bikes made from reinforced plastics. Hydraulic brakes offer significantly better performance for a mountain bike over traditional cable rim break or cable disk break. Nevertheless, people are unable to appreciate advantage because of the price. The traditional hydraulic disk brake systems are made of aluminum alloy. With a proper design, it may be possible to create a lever assembly and a caliper that would be competitive on price and weight. Often bike parts are judged by how much they weight, the less they weight, the more they are desirable. This is only true to a certain extent because lighter parts come with a premium price tag. The current project proposed that the injection molded brakes would be lighter because of the material being used and cost-effective because the manufacturing process can be utilized. Commercial reinforced plastic composites have been identified as lighter materials compared to aluminum alloy. Through an iterative design process, the final designs of lever assembly and caliper have been achieved. The stopping force has been determined considering the abrupt stoppage with a standard weight person riding the bike. Based on the stopping force the stress analyses were obtained using FEA simulation for master cylinder, slave cylinder, and lever. At the end, the final designs were chosen based on the stress analyses and manufacturability.

Correction for ‘Modelling and prediction of the thermophysical properties of aqueous mixtures of choline geranate and geranic acid (CAGE) using SAFT-γ Mie’ by Silvia Di Lecce et al., RSC Adv., 2019, 9, 38017–38031. DOI: 10.1039/C9RA07057E

This article builds on prior research demonstrating that intensive faculty training in alcohol and other drug (AOD) identification and treatment methods can result in increases in AOD knowledge and teaching efficacy. We provide examples of how faculty participants in the Alcohol and Other Drugs Education Program have adapted their teaching in clinical practice, research methods, and addiction specialty courses as a result of participation in our immersion-based training program. Examples from 3 schools provide ideas for teaching innovations and serve as templates for faculty interested in advancing their teaching and the integration of AOD-related content into the social work curriculum.

Terrorists frequently use explosives and they represent an imminent threat to national and global security. Recent events highlight the necessity of explosive detection, demonstrating the need for developing and applying new sensors for explosive gas detection. Semiconducting metal oxide gas sensors can be incorporated into electronic noses, which provide a cheap, portable and highly sensitive device. Using unmodified, admixed and 2-layered sensors consisting of WO3 and chromium titanium oxide (CTO), an array of seven heterojunction semiconducting metal oxide sensors was produced. All seven sensors were tested against four gases associated with explosive materials. The sensitivity was improved by using 2-layered sensors in response to ethanol, ammonia and nitromethane, whereas the admixed sensors showed high sensitivity when exposed to nitrogen dioxide. The selectivity of the array of sensors was tested using machine-learning techniques with a support vector machine. The technique produced good data classification when classifying the gases used within the study.

Eight imidazolium-based salts with the weakly-coordinating anions [BArF]− and [Al(OtC4F9)4]− ([BArF]− = tetrakis{3,5-bis(trifluoromethyl)phenyl}borate) have been synthesized. Characterization by 1H NMR spectroscopy shows that the salts are fully dissociated in solution. Six examples have been further characterized by X-ray crystallography, revealing that weak hydrogen bonds do occur in the solid phase between the imidazolium cations and weakly coordinating anions. Comparison with the bulky [IDiPPH] imidazolium cation (IDiPPH = 1,3-bis{2,6-bis(diisopropyl)phenyl}imidazolium) shows that large steric bulk close to the imidazolium protons can preclude hydrogen bonds from forming. Differential scanning calorimetry of the salts reveal that all are thermally stable up to 200 °C which renders them as potentially suitable background electrolytes for electrochemical processes which take place at elevated temperatures.

Wind Farm Operations and Maintenance has challenges in delivering cargo safely and efficiently and with manning in high sea states. Wind farms farther offshore further increases pressures on vessel design, technicians, safety and costs. Working within the ambit of ‘Innovate UK’ funded Wind Farm Autonomous Ship Project, Houlder Ltd have been developing the concept design of a Wind Farm Support Vessel that can operate autonomously during transit and while delivering cargo to offshore wind turbine. The aspired degree of automation is that for the vessel to be remotely operated from ashore. Vessel functions have been identified, working in conjunction with industry and project partners, who are developing vessel control and advanced autonomy, on-board health diagnostics, decision support logistics algorithms, data flow and logistics management, and cost performance analysis, as part of the project. The Concept is expected to reduce operating costs, especially fuel and crew related, while improving safety of operations. This paper will focus on the re-think, re-design and refining of vessel design that the autonomous vessel concept has accorded. The discussion will follow through the design spiral for features of spaces, stability and machinery systems, besides the innovation and integration of autonomous cargo handling solution for the wind farm O&M.

A series of “light metal” metal–organic frameworks containing secondary building units (SBUs) based on Li+ and Na+ cations have been prepared using the silicon-centered linkers MexSi(p-C6H4CO2H)4-x (x = 2, 1, 0). The unipositive charge, small size, and oxophilic nature of the metal cations give rise to some unusual and unique SBUs, including a three-dimensional nodal structure built from sodium and oxygen ions when using the triacid linker (x = 1). The same linker with Li+ cations generated a chiral, helical SBU, formed from achiral starting materials. One-dimensional rod SBUs are observed for the diacid (x = 2) and tetra-acid (x = 0) linkers with both Li+ and Na+ cations, where the larger size of Na+ compared to Li+ leads to subtle differences in the constitution of the metal nodes.

Work processes such as assembly in manufacturing are often highly complex and change frequently due to today’s high rate of technological innovation. Thus, the usage of assistance services to support workers in assembly can result in significant benefits. However, adequate assistance requires knowledge about the actual actions of the workers. In this chapter, we present a use case in aviation, where a manufacturing environment that carries no sensors at all is extended with off-the-shelf sensors that enable capturing the effect of physical actions and, in consequence, adequate reactions of a support system. We also give an overview of technologies of the Internet of Things and a category of human errors in industry to simplify the replication of the described digitization in other workplaces.

This paper describes the present tidal regime in the Red Sea. Both the diurnal and the semidiurnal tidal amplitudes are small because of the constricted connection to the Gulf of Aden and the Indian Ocean, at the Bab el Mandeb Strait. Semidiurnal tides have a classic half-wave pattern, with a central amphidrome, zero tidal range, between Jeddah and Port Sudan. We present a high resolution numerical model output of several tidal constituents, and also model the amphidrome position in terms of ingoing and outgoing tidal Kelvin waves. We quantify the energy budgets for fluxes and dissipation.

We report results for the electrochemistry of the germanium(II) tri-halide anions, [GeCl3]?, [GeBr3]? and [GeI3]?, in supercritical difluoromethane containing 60?mm [NnBu4][BF4] at 19.1?MPa and 358?K. The voltammetry shows mass-transport-limited currents for reduction to germanium at gold on the first scan. There is no evidence of a germanium stripping peak and, on subsequent scans, the electrode slowly passivates with the deposition of approximately 0.4??m of material. The redox potentials for the reduction of the three tri-halides are in the order [GeCl3]?

The hexahalide salts, [NnBu4]3[LaCl6], [BMPYRR]3[LaCl6] (BMPYRR = 1-butyl-1-methylpyrrolidinium), [EMIM]3[MX6] (EMIM = 1-ethyl-3-methylimidazolium; M = La, X = Cl, Br, I; M = Sc, Y, Ce, X = Cl) and [EDMIM]3[MX6] (EDMIM = 1-ethyl-2,3-dimethylimidazolium; M = Y, X = Cl; M = La, X = Cl, I) have been prepared and X-ray crystal structures determined for several of them, with a view to probing the effect of varying the trivalent metal ion, the halide and the counter-cation on the structures adopted in the solid state. The crystal structures of the EMIM and EDMIM salts show extensive H-bonding between the halide ligands and organic cations; based upon the H-bonding distances, this appears to be strongest for the [EMIM]3[MCl6] salts, becoming progressively weaker for heavier metal ion or halide. In terms of the cations, changing from EMIM to EDMIM also reduces the strength of the H-bonding. The strength of the cation–anion pairing in solution has also been probed in solution via NMR spectroscopy where possible (45Sc, 89Y and 189La) and, for the EMIM salts, via the shift of ?(H2) relative to [EMIM]Cl at a standard concentration. The trends observed in solution mirror those determined in the solid state.

The Newlyn Tidal Observatory is the most important sea level station in the United Kingdom. It commenced operations in 1915 as part of the Second Geodetic Levelling of England and Wales, and the mean sea level determined from the tide gauge during the first six years (May 1915–April 1921) defined Ordnance Datum Newlyn (ODN) which became the national height datum for the whole of Great Britain. The 100 years of sea level data now available have contributed significantly to many studies in oceanography, geology, and climate change. This paper marks the centenary of this important station by reviewing the sea level (and, more recently, detailed land level) measurements and Newlyn's contributions to UK cartography, geodesy and sea-level science in general. Recommendations are made on how sea and land level measurements at Newlyn might be enhanced.

For the first time, a versatile electrolyte bath is described that can be used to electrodeposit a wide range of p-block elements from supercritical difluoromethane (scCH2 F2 ). The bath comprises the tetrabutylammonium chlorometallate complex of the element in an electrolyte of 50×10(-3) mol dm(-3) tetrabutylammonium chloride at 17.2 MPa and 358 K. Through the use of anionic ([GaCl4 ](-) , [InCl4 ](-) , [GeCl3 ](-) , [SnCl3 ](-) , [SbCl4 ](-) , and [BiCl4 ](-) ) and dianionic ([SeCl6 ](2-) and [TeCl6 ](2-) ) chlorometallate salts, the deposition of elemental Ga, In, Ge, Sn, Sb, Bi, Se, and Te is demonstrated. In all cases, with the exception of gallium, which is a liquid under the deposition conditions, the resulting deposits are characterised by SEM, energy-dispersive X-ray analysis, XRD and Raman spectroscopy. An advantage of this electrolyte system is that the reagents are all crystalline solids, reasonably easy to handle and not highly water or oxygen sensitive. The results presented herein significantly broaden the range of materials accessible by electrodeposition from supercritical fluid and open up the future possibility of utilising the full scope of these unique fluids to electrodeposit functional binary or ternary alloys and compounds of these elements.

This paper presents a comparative study on gas sensing properties of pure and doped ZnO nano powders. To facilitate doping, Aluminum and nickel precursors were used as dopant/co-dopants using a simple and reproducible co-precipitation method. Pure ZnO and samples with compositions Zn0.99M0.01O (M = Al/Ni) and Zn0­.99Al0.005Ni0.005O were prepared to evaluate the effect of Al/Ni doping/co-doping. The samples were characterized using X-ray diffraction (XRD), Raman spectroscopy, and field emission scanning electron microscopy (FESEM). The electrical conductivity of these samples was measured. A temperature variation of electrical conductivity was used to calculate activation energy of various samples. The samples were subjected to ethanol tests at concentration ranging between 10 and 50 ppm. The metal ion doping showed a marked increase in relative responsiveness of all doped samples. The variation in gas sensing response has been correlated with electrical conductivity, activation energy, and morphology of these samples. This report clearly demonstrates inter-connection of multiple factors influencing gas sensing properties of metal oxide semiconductors (MOS). Similar tests performed with methanol exposure show much reduced relative responses for all the samples in comparison to ethanol. These studies can be exploited for tailoring of futuristic sensors with improved responses.

A hexacarboxylic acid with a trisiloxane backbone (L-H6) has been prepared and applied in MOF construction. L-H6 itself crystallizes as an unusual 2D hydrogen-bonded network. Reaction of L-H6 with Mn(ii) gave IMP-20 and with Zn(ii) gave IMP-21: both are 3D MOFs incorporating Si-O-Si-O-Si linkages.

Tetramethyl orthosilicate (TMOS) is shown to be an effective reagent for direct amidation of aliphatic and aromatic carboxylic acids with amines and anilines. The amide products are obtained in good to quantitative yields in pure form directly after workup without the need for any further purification. A silyl ester as the putative activated intermediate is observed by NMR methods. Amidations on a 1 mol scale are demonstrated with a favorable process mass intensity.