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The reverse water-gas shift reaction (rWGS) is of particular interest as it is the first step to producing high-added-value products from carbon dioxide (CO 2) and renewable hydrogen (H 2), such as synthetic fuels or other chemical building blocks (e.g. methanol) through a modified Fischer-Tropsch process. However, side reactions and material deactivation issues, depending on the conditions used, still make it challenging. Efforts have been put into developing and improving scalable catalysts that can deliver high selectivity while at the same time being able to avoid deactivation through high temperature sintering and/or carbon deposition. Here we design a set of perovskite ferrites specifically tailored to the hydrogenation of CO 2 via the reverse water-gas shift reaction. We tailor the oxygen vacancies, proven to play a major role in the process, by partially substituting the primary A-site element (Barium, Ba) with Praseodymium (Pr) and Samarium (Sm), and also dope the B-site with a small amount of Nickel (Ni). We also take advantage of the exsolution process and manage to produce highly selective Fe-Ni alloys that suppress the formation of any by-products, leading to up to 100% CO selectivity. • Partial A-site substitution with Pr, Sm, affects oxygen vacancies formation and microstructure. • Incorporation of Ni on the B-site affects the morphology and stability of the perovskites and induces exsolution. • Combination of Fe-Ni alloy formation and pre-treatment optimization leads up to 100% selectivity to CO. [ABSTRACT FROM AUTHOR]

Early Paleozoic evolution of the northern Gondwana margin is interpreted from integrated in situ U-Pb and Hf-isotope analyses on detrital zircons that constrain depositional ages and provenance of the Lancang Group, previously assigned to the Simao Block, and the Mengtong and Mengdingjie groups of the Baoshan Block. A meta-felsic volcanic rock from the Mengtong Group yields a weighted mean 206 Pb/ 238 U age of 462 ± 2 Ma. The depositional age for the previously inferred Neoproterozoic Lancang and Mengtong groups is re-interpreted as Early Paleozoic based on youngest detrital zircons and meta-volcanic age. Detrital U-Pb zircon analyses from the Baoshan Block define three distinctive age peaks at older Grenvillian (1200–1060 Ma), younger Grenvillian (~ 960 Ma) and Pan-African (650–500 Ma), with εHf(t) values for each group similar to coeval detrital zircons from western Australia and northern India. This suggests that the Baoshan Block was situated in the transitional zone between northeast Greater India and northwest Australia on the Gondwana margin and received detritus from both these cratons. The Lancang Group yields a very similar detrital zircon age spectrum to that of the Baoshan Block but contrasts with that for the Simao Block. This suggests that the Lancang Group is underlain by a separate Lancang Block. Similar detrital zircon age spectra suggest that the Baoshan Block and the Lancang Block share common sources and that they were situated close to one another along the northern margin of East Gondwana during the Early Paleozoic. The new detrital zircon data in combination with previously published data for East Gondwana margin blocks suggests the Early Paleozoic Proto-Tethys represents a narrow ocean basin separating an “Asian Hun superterrane” (North China, South China, Tarim, Indochina and North Qiangtang blocks) from the northern margin of Gondwana during the Late Neoproterozoic-Early Paleozoic. The Proto-Tethys closed in the Silurian at ca. 440–420 Ma when this “Asian Hun superterrane” collided with the northern Gondwana margin. Subsequently, the Lancang Block is interpreted to have separated from the Baoshan Block during the Early Devonian when the Paleo-Tethys opened as a back-arc basin. [ABSTRACT FROM AUTHOR]

Hainan Island is a key component of the South China Sea region and provides insights on regional geological evolution since the Paleozoic. Ten new LA-ICPMS zircon U-Pb ages from granites of Hainan Island include Late Permian (254 ± 3 Ma; 252 ± 3 Ma), Middle-Late Triassic (243 ± 2 Ma; 242 ± 3 Ma; 240 ± 2 Ma; 228 ± 2 Ma) and late Early to early Late Cretaceous (105 ± 1 Ma; 101 ± 1 Ma; 96 ± 2 Ma; 95 ± 3 Ma) ages. All samples in the present study, including late Permian, Middle-Late Triassic, and late Early to early Late Cretaceous granitic rocks show geochemical characteristics similar to those of calc-alkaline to high-K calc-alkaline I-type granites. Major and trace element geochemical variations show that during petrogenesis, these granites experienced fractional crystallization of minerals (e.g., Ti oxides and apatite). Compared to the late Permian and Middle-Late Triassic granitic rocks, middle to late Cretaceous granites generally have lower initial 87 Sr/ 86 Sr ratios of 0.70594 to 0.70886, lower T DM2 ages of 1314 to 1382 Ma, and higher εNd(t) of − 4.94 to − 5.96, implying that the magmatic source for Cretaceous granites received more significant contribution from juvenile material relative to that for Permo-Triassic granites. These new data, combined with data from literature for Hainan Island and the South China Sea (SCS) region underpin a conceptual model for late Paleozoic to Mesozoic tectonic evolution for Hainan Island and the general SCS region as follows, (a) Late Permian (272–252 Ma), the initiation and development of continental arc related to the subduction of Palaeo-Tethys ocean; (b) Triassic (249–228 Ma), continued arc magmatism, the gradual cessation of Palaeo-Tethys subduction and subsequent development of an extensional setting; (c) Early Jurassic to early Cretaceous (190–130 Ma), the development of an Andean-type continental arc, and regional tectonic regime switch to the westward subduction of the Palaeo-Pacific plate; (d) Middle to late Cretaceous (128–70 Ma), the continuation of the Andean-type arc, the development of an extensional setting due to slab rollback, and the cessation (~ 70 Ma) of Palaeo-Pacific plate subduction. [ABSTRACT FROM AUTHOR]

Highlights: [•] Aluminium(salen) catalysed cyclic carbonate synthesis. [•] Influence of reactor design. [•] Study of CO2 solubility in epoxide. [•] Study of CO2 solubility in glycidol/glycerol carbonate mixtures. [ABSTRACT FROM AUTHOR]

Here we provide an overview of recent developments in high-temperature electroceramic oxides for the transport of gas-phase species via dual ion conductivity. The electroceramic oxide is used in the form of a dense membrane when it exhibits ionic conductivity for two distinct ions and as a porous host matrix supporting a guest liquid-phase ion conductor when it supplies a path for a single ion, the path for the other being supplied by the liquid phase. We focus on water transport and carbon dioxide transport in single and dual phase membranes, respectively. [ABSTRACT FROM AUTHOR]

Abstract: A Permo-Triassic volcanic arc system, the Sukhothai Arc, is recognised between the Indochina and Sibumasu continental blocks. The Chanthaburi terrane is here interpreted as a fault-detached, highly disrupted southern segment of the Sukhothai Arc, occupying part of southeastern Thailand and extending into Cambodia. The Klaeng tectonic line is defined as the boundary between the Chanthaburi terrane and Sibumasu block. The stratigraphy of the Chanthaburi terrane is compared with that of the Sukhothai terrane in Northern Thailand. The Late Palaeozoic–Mesozoic sequences of these two volcanic arc terranes in the Sukhothai Zone share important similarities, but show marked contrasts to those of the Sibumasu and Indochina blocks, where the Late Permian–Triassic is largely absent due to the Indosinian I unconformity (western Indochina) or is dominantly carbonates with little terrigenous clastic input (Sibumasu). There is no clear evidence of pre-Carboniferous sedimentary rocks for either the Sukhothai or Chanthaburi terranes. Late Permian lyttoniid brachiopod shale near Klaeng in the Chanthaburi terrane was revisited. The brachiopod, previously reported as Leptodus, is re-identified to Oldhamina, the genus previously known, elsewhere in Southeast Asia, only in the Huai Tak Formation of the Sukhothai terrane. Oldhamina in Thailand is confined to the Sukhothai Arc. The marine stratigraphy of the Sukhothai Arc is represented by a Permian–Triassic lithological succession of mixed carbonates and siliciclastics, with common volcanic material. The Late Permian and Triassic litho- and biostratigraphy of the Chanthaburi terrane are comparable with the upper Ngao and Lampang groups of the Sukhothai terrane; in particular, they share similar successions from Oldhamina brachiopod bearing shale to Palaeofusulina–Colaniella foraminifer bearing limestone in the latest Permian. Marine depositional conditions were terminated on the Sukhothai Arc by end-Triassic times, later than on the Indochina block (Late Permian) but earlier than on the Sibumasu block (Jurassic/Cretaceous). [Copyright &y& Elsevier]

Abstract: Sundaland comprises a heterogeneous collage of continental blocks derived from the India–Australian margin of eastern Gondwana and assembled by the closure of multiple Tethyan and back-arc ocean basins now represented by suture zones. The continental core of Sundaland comprises a western Sibumasu block and an eastern Indochina–East Malaya block with an island arc terrane, the Sukhothai Island Arc System, comprising the Linchang, Sukhothai and Chanthaburi blocks sandwiched between. This island arc formed on the margin of Indochina–East Malaya, and then separated by back-arc spreading in the Permian. The Jinghong, Nan–Uttaradit and Sra Kaeo Sutures represent this closed back-arc basin. The Palaeo-Tethys is represented to the west by the Changning–Menglian, Chiang Mai/Inthanon and Bentong–Raub Suture Zones. The West Sumatra block, and possibly the West Burma block, rifted and separated from Gondwana, along with Indochina and East Malaya in the Devonian and were accreted to the Sundaland core in the Triassic. West Burma is now considered to be probably Cathaysian in nature and similar to West Sumatra, from which it was separated by opening of the Andaman Sea basin. South West Borneo and/or East Java-West Sulawesi are now tentatively identified as the missing “Argoland” which must have separated from NW Australia in the Jurassic and these were accreted to SE Sundaland in the Cretaceous. Revised palaeogeographic reconstructions illustrating the tectonic and palaeogeographic evolution of Sundaland and adjacent regions are presented. [ABSTRACT FROM AUTHOR]

Abstract: The end-Permian mass extinction is now robustly dated at 252.6±0.2Ma (U–Pb) and the Permian–Triassic (P–T) GSSP level is dated by interpolation at 252.5Ma. An isotopic geochronological timescale for the Late Permian–Early Triassic, based on recent accurate high-precision U–Pb single zircon dating of volcanic ashes, together with calibrated conodont zonation schemes, is presented. The duration of the Early Triassic (Induan+Olenekian stages) is estimated at only 5.5 million years. The duration of the Induan Stage (Griesbachian+Dienerian sub-stages) is estimated at ca. one million years and the early Olenekian (Smithian sub-stage) at 0.7 million years duration. Considering this timescale, the “delayed” recovery following the end-Permian mass extinction may not in fact have been particularly protracted, in the light of the severity of the extinction. Conodonts evolved rapidly in the first 1 million years following the mass extinction leading to recognition of high-resolution conodont zones. Continued episodic global environmental and climatic stress following the extinction is recognized by multiple carbon isotope excursions, further faunal turnover and peculiar sedimentary and biotic facies (e.g. microbialites). The end-Permian mass extinction is interpreted to be synchronous globally and between marine and non-marine environments. The nature of the double-phased Late Permian extinction (at the Guadalupian–Lopingian boundary and the P–T boundary), linked to large igneous provinces, suggests a primary role for superplume activity that involved geomagnetic polarity change and massive volcanism. [Copyright &y& Elsevier]

Abstract: Ancient accretionary wedges have been recognised by the presence of glaucophane schist, radiolarian chert and mélange. Recent techniques for the reconstruction of disrupted fragments of such wedges by means of radiolarian biostratigraphy, provide a more comprehensive history of ocean plate subduction and successive accretion of ocean floor materials from the oceanic plate through offscraping and underplating. Reconstructed ocean floor sequences found in ancient accretionary complexes in Japan comprise, from oldest to youngest, pillow basalt, limestone, radiolarian chert, siliceous shale, and shale and sandstone. Similar lithologies also occur in the mélange complexes of the Philippines, Indonesia, Thailand and other regions. This succession is called ‘Ocean Plate Stratigraphy’ (OPS), and it represents the following sequence of processes: birth of the oceanic plate at the oceanic ridge; formation of volcanic islands near the ridge, covered by calcareous reefs; sedimentation of calcilutite on the flanks of the volcanic islands where radiolarian chert is also deposited; deposition of radiolarian skeletons on the oceanic plate in a pelagic setting, and sedimentary mixing of radiolarian remains and detrital grains to form siliceous shale in a hemipelagic setting; and sedimentation of coarse-grained sandstone and shale at or near the trench of the convergent margin. Radiolarian biostratigraphy of detrital sedimentary rocks provides information on the time and duration of ocean plate subduction. The ages of detrital sediments becomes younger oceanward as younger packages of OPS are scraped off the downgoing plate. OPS reconstructed from ancient accretionary complexes give us the age of subduction and accretion, direction of subduction, and ancient tectonic environments and is an important key to understanding the paleoenvironment and history of the paleo-oceans now represented only in suture zones and orogenic belts. [Copyright &y& Elsevier]

The use of vaccines for the prophylaxis of influenza in children is limited. This is despite high annual rates of influenza in children and despite the complications caused by influenza in children with chronic respiratory illnesses. The disease burden of influenza on infants and young children is reviewed and the potential of recommended influenza vaccination in healthy children, to reduce the direct and indirect health and socio-economic costs, is considered. Clinical experience with a virosome-formulated subunit influenza vaccine in children is presented. These clinical trials in children have shown a virosome-formulated subunit influenza vaccine to be immunogenic and well tolerated, indicating that it might be recommended for immunising healthy infants and children against influenza virus. [Copyright &y& Elsevier]

Inflexal®V, a novel virosome-based trivalent influenza vaccine, has been shown to be highly immunogenic and well tolerated in children, young adults, and the elderly. Here we discuss the techniques for the manufacture of Inflexal®V, highlighting the purity and consistency of the manufacturing process. Key factors to be taken into account in the construction of Inflexal®V are the retention of the natural presentation of antigens, its biodegradability and the presentation of few adverse events. The constituents of the vaccine were also carefully considered based on suitability for human use, adjuvanticity and an innate lack of toxicity. [Copyright &y& Elsevier]

The Tibetan Plateau and western Yunnan are known to have formed by the amalgamation of Gondwana-derived continental blocks and arc terranes as a result of Tethyan subduction followed by continental collisions during the Paleozoic, Mesozoic and Cenozoic. The Devonian and the southern Lancangjiang zone, western Yunnan is a critical period and key region for studying the transformation between the “Proto-Tethyan” and Paleo-Tethyan oceanic systems. New geochemical data and LA-ICPMS U–Pb zircon ages of the Late Devonian volcanogenic sediments from the southern Lancangjiang zone in western Yunnan, SW China, are presented. The studied sedimentary rocks of the Nanguang Formation are volcaniclastic rocks with high volcanic lithic content (55–65%, mostly andesite, dacite, with some rhyolite and tuffs). Whole rock geochemistry, zircon trace elements and detrital modal analyses indicate derivation from a subduction-related magmatic arc. Three tuff samples yield Late Devonian weighted mean 206 Pb/ 238 U ages of 378 ± 4 Ma, 366 ± 5 Ma and 382 ± 8 Ma, suggesting a Late Devonian depositional age. 104 zircon U–Pb analyses on 104 zircon grains from two sandstone samples present extremely tight age clusters, mostly ranging from 380 Ma to 360 Ma. This indicates a single Late Devonian igneous source. A short transport distance and a high rate of denudation and deposition within an arc-related basin are considered likely for the tuffs and volcaniclastic rocks in this study. This implies the presence of an as yet unidentified Late Devonian magmatic arc in the southern Lancangjiang zone. The cryptic Late Devonian arc is likely to represent either a continuation of Late Ordovician–Late Silurian “Proto-Tethyan” subduction or the initial stage of the Paleo-Tethyan Lincang Arc and indicates that subduction of the Changning-Menglian ocean beneath the Simao/Indochina Block occurred in the Late Devonian. [ABSTRACT FROM AUTHOR]

Iron oxide has been widely used as an oxygen carrier material (OCM) for hydrogen production by chemical looping due to its favourable thermodynamic properties. In spite of this, iron oxide loses much of its activity after redox cycling mainly due to sintering and agglomeration. Perovskites, such as La 0.7 Sr 0.3 FeO 3-δ (LSF731), have been suggested as potential candidate OCMs for hydrogen production due to their excellent oxygen transport properties and stability under cycling. However, hydrogen production per cycle for a similar carrier weight is lower than with iron oxide. This work proposes the use of composite OCMs made of iron oxide clusters embedded in an LSF731 matrix. The perovskite matrix facilitates oxygen transport to the iron oxide clusters while preventing agglomeration. Two preparation methods, mechanical mixing and a modified Pechini method, were used to obtain composite materials with different iron oxide weight fractions, 11 and 30 wt.%. The reactivity of these OCMs was studied in a thermogravimetric analyser. Hydrogen production and carrier stability were investigated in a microreactor over 25 redox cycles while periodically feeding carbon monoxide and water in order to produce carbon dioxide and hydrogen in separate streams. Hydrogen production was stable over 25 cycles for LSF731 and the composite OCM with 30 wt.% iron oxide produced by the modified Pechini method but iron oxide particles alone underwent a decrease in the hydrogen production with cycling. The hydrogen production during the 25th cycle was eight times higher for the composite material than for iron oxide alone and four times higher than for LSF731. The hydrogen production was therefore also higher than that expected from a simple combination of the iron oxide and LSF731 alone, indicating a synergetic effect whereby the LSF731 may have a higher effective oxygen capacity when in the form of the composite material. [ABSTRACT FROM AUTHOR]

Abstract: Reactor modules consisting of four gas-tight microtubular membranes made of the mixed oxygen ion and electron conducting perovskite, La0.6Sr0.4Co0.2Fe0.8O3−δ have been tested for oxygen permeation and hydrogen production by membrane-based steam reforming, i.e., simultaneous syngas production coupled with water splitting. The membranes were subjected to two known axial temperature profiles in the temperature of 900°C. The microtubes showed good stability under reaction conditions, operating over a total operation period of ca 400h of oxygen permeation followed by ca 400h of steam reforming. An induction period of approximately 30h was observed before steam reforming commenced. Both the methane and water side outlet gas compositions were measured which allowed for accurate material balance; this indicated that the hydrogen production occurred due to oxygen flux across the membrane and not just surface reaction. Post operation analysis of the microtubes revealed the presence of a strontium enriched dense layer on the water exposed membrane surface and of crystallites enriched with cobalt and sulfur on the methane feed side surface. [Copyright &y& Elsevier]

Abstract: The decomposition of sodium dodecylbenzene sulfonate (SDBS) in water by means of ultrasound irradiation at 20kHz was investigated. Experiments were conducted at surfactant concentrations of 175, 260 and 350mgl−1, liquid volumes of 120, 170 and 220ml, temperatures of 20, 30 and 45°C and applied power of 40, 80 and 125W. The extent of degradation was followed monitoring substrate and organic carbon concentrations, while hydrogen peroxide concentration was also measured; the latter is a product of water sonolysis due to hydroxyl radical recombination. 80% SDBS conversion was achieved after 120min of sonication at 125W and 30°C; nonetheless, SDBS and its degradation intermediates proved difficult to oxidise as only about 20–25% of the initial carbon content was transformed to carbon dioxide. At the initial stages of the reaction, degradation rate appears to be only weakly dependent on the substrate concentration with the rate increasing from 3.1 to 4mgl−1 min−1 with increasing concentration from 175 to 350mgl−1. Degradation appears to occur at the bubble-liquid interface through hydroxyl radical-mediated reactions whose role was established by performing experiments in the presence of radical scavengers, namely potassium bromide and sodium benzoate. Degradation rates increased with increasing power and decreasing temperature and volume. [Copyright &y& Elsevier]

Most pathogens gain access to their host through mucosal surfaces. It is therefore desirable to develop vaccination strategies that lead to mucosal immune responses. Ideally, a vaccine should be administered mucosally in order to elicit mucosal protection. Several attenuated live viral and bacterial pathogens are registered as oral vaccines for human use, including the oral polio vaccine (Sabin) as well as attenuated strains of Salmonella typhi and Vibrio cholerae. These attenuated bacterial live vaccines—S. typhi Ty21a as well as V. cholerae CVD 103-HgR—are employed as vaccines against typhoid and cholera, respectively. In this manuscript, we review the immune responses that are induced by these vaccines, with a focus on mucosal immunity. [Copyright &y& Elsevier]