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Zircon U-Pb ages, major element and trace element compositions, and Sr, Nd, and Pb isotopic compositions for late Mesozoic granites from the southern Jiaodong Peninsula (eastern China) were determined. Ages for the Wulianshan, Xiaozhushan, and Dazhushan plutons are 119.1-122.3, 114.2, and 108.9 Ma, respectively. Major and trace element characteristics show that these granitic rocks belong to alkaline, A-type granites formed in an extensional setting. Trace element compositions show strong, variable negative anomalies in Ba, K, P and Ti, and positive anomalies in Rb, Th, U, Pb, Ce, Zr, and Hf, which are typical characteristics of A-type granites. Variable Sr and Nd isotopic compositions, 87Sr/86Sr(i) = 0.70540-0.7071 and εNd(t) = −14.5 to −20.9. Whole-rock Pb isotopic compositions have the following ranges, (206Pb/204Pb)t = 15.707-16.561, (207Pb/204Pb)t = 15.376-16.462, and (208Pb/204Pb)t = 36.324 to 37.064. Isotopic modelling indicates an origin that lies between mantle tapped by Cenozoic basalts around the Tan-Lu megafault and lower continental crust (LCC), and which can be explained by mixing of 11-18% mantle and 82-89% LCC. Based on new and compiled data, we suggest that the southern Jiaodong Peninsula, as well as the Laoshan area, was in a regional extensional setting of an orogenic belt during 106-126 Ma. The granitic rocks may be the result of late Mesozoic lithospheric thinning and decratonization (i.e. late Mesozoic craton destruction event occurring throughout eastern China). [ABSTRACT FROM AUTHOR]

Improved biostratigraphic dating and enhanced understanding of the stratigraphy and depositional and tectonic environments of Devonian and Carboniferous sequences in Malaysia have resolved ambiguities in previous published work and better constrain the nature and timing of the stages of tectonic evolution of the region. The Devonian and Carboniferous stratigraphy of theMalay Peninsula is discussed within a tectonic framework that includes a western Sibumasu Terrane and an eastern Sukhothai Arc (Indochina) block separated by the Bentong-Raub Suture Zone that represents the former Devonian-Triassic Palaeo-Tethys Ocean. The stratigraphy and depositional environments of the Devonian and Carboniferous of Peninsular Malaysia provide important insights into the switch from deposition in shallow shelf to deeper-water margin-slope environments on the passive margin of Gondwana during the early development of the Palaeo-Tethys Ocean. In addition, the Devonian and Carboniferous sediments and faunas of theWestern Belt of the Malay Peninsula support and are consistent with placement of the Sibumasu Terrane on the Palaeozoic margin of AustralianGondwana until the early Permian (Sakmarian). Carboniferous sedimentary rocks of the Eastern Belt of theMalay Peninsula were deposited on the margin of the equatorial Indochina Block onwhich the SukhothaiArc was constructed. Previously erected stratigraphical units, such as the 'Karak Formation', 'Bentong Group', 'Raub Group', and 'Pelong Beds'for Bentong-Raub Suture Zone complex rocks, are meaningless as stratigraphic units, and their use should be discontinued. Devonian and Carboniferous conodont biostratigraphy in the Malay Peninsula is relatively poorly known. The Lower Devonian Pterospathodus amorphognathoides Zone, Ozarkodina eosteinhornensis Zone, and Icriodus woschmidti Zone faunas are known from the Mempelam Limestone of Langkawi and Perlis, and the Upper Devonian (Frasnian) Palmatolepis linguiformis Zone faunas occur in the Sanai Limestone of Perlis. Conodont faunas of the Kanthan Limestone in Perak represent Lower-MiddleDevonian (Emsian-Giventian) Eocostapolygnathus gronbergi Zone-Polygnathus asymmetricus Zone faunas, andMississippian upper Tournaisian Scaliognathus anchoralis Zone, Visean Lochriea commutatus Zone, and Gnathodus bilineatus Zone faunas. Basal Pennsylvanian Declinognathodus noduliferus Zone faunas are also present. Significant reworking of conodonts into the Tournaisian and Visean limestones is recorded. Conodont faunas of the Panching Limestone in the eastern Belt of the Malay Peninsula represent the earliest Pennsylvanian D. noduliferus s.l.-Rhachistognathus primus Zone. [ABSTRACT FROM AUTHOR]

Limestones exposed north of Raub, Pahang, Malaysia, and sandwiched between the Bentong-Raub Suture Zone and the westernmost margin of the Sukhothai Arc terrane, yield a late Dienerian (late Induan) conodont fauna. The co-occurrence of Neospathodus dieneri Sweet (morphotypes 1, 2 and 3) and Neospathodus pakistanensis Sweet represents the Neospathodus dieneri morphotype 3 sub-zone of the Neospathodus dieneri Zone. The sampled limestones are interpreted as the northwards extension of the Jerus Limestone which crops out near Cheroh and Jerus villages, significantly extending the known outcrop of the Jerus Limestone northwards. The Jerus Limestone is interpreted as hemipelagic and formed in a foredeep or forearc setting on top of the accretionary complex formed by eastwards subduction of the Palaeo-Tethys during the Lower to Middle Triassic. [ABSTRACT FROM AUTHOR]

As a low‐cost alternative to noble metals, Cu plays an important role in industrial catalysis, such as water‐gas shift reaction, methanol or ethanol oxidation, hydrogenation of oils, CO oxidation, among many others. An important step in optimizing Cu catalyst performance is control of nanoparticles size, distribution, and the interface with the support. While proton conducting perovskites can enhance the metal catalytic activity when acting as the support, there has been limited investigation of in situ growth of Cu metal nanoparticles from the proton conductors and its catalytic performance. Here, Cu nanoparticles are tracked exsolved from an A‐site‐deficient proton‐conducting barium cerate‐zirconate using scanning electron microscopy, revealing a continuous phase change during exsolution as a function of reduction temperature. Combined with the phase diagram and cell parameter change during reduction, a new exsolution mechanism is proposed for the first time which provides insight into tailoring metal particles interfaces at proton conducting oxide surfaces. Furthermore, the catalytic behavior in the CO oxidation reaction is explored and, it is observed that these new nanostructures can rival state of the art catalysts over long term operation. [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: 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: Calibration of kinetic models of wet air oxidation (WAO) is usually performed through minimisation algorithms with respect to total organic carbon (TOC) experimental data. However, the reliability of the estimated value of the kinetic parameters is frequently not reported. Moreover, the influence of data quantity/quality in the kinetic parameters identifiability is not properly assessed. The objective of this study is to compare the calibration goodness of a proposed kinetic model when using one set of data (total effluent TOC [TOCeff]) or two sets of independent experimental measurements (total effluent TOC [TOCeff] and residual TOC of target pollutant [TOC[A]]). The systematic comparison was made using identifiability analysis with contour plots of both objective functions and the confidence intervals were calculated through the Fisher information matrix (FIM). The experimental data used in this study comes from a previous one, where WAO was investigated as a suitable precursor for the biological treatment of industrial wastewater containing high concentrations of o-cresol or 2-chlorophenol [M.E. Suárez-Ojeda, J. Carrera, I.S. Metcalfe, J. Font, Wet air oxidation (WAO) as a precursor to biological treatment of substituted phenols: refractory nature of the WAO intermediates, Chem. Eng. J. 144 (2008) 205–212.]. The results show that the model correctly fitted the experimental [TOCeff] in all cases with less than 6% as averaged relative deviation, either using one set of data ([TOCeff]) or two sets of independent experimental measures ([TOCeff] and [TOC[A]]) in the objective function. However, when using only [TOCeff], the model was not capable of fitting the proportion between [TOC[A]] and intermediates TOC. The obtained E ACT for the calibration made with [TOCeff] and [TOC[A]] were 71±20kJmol−1 (R 2 =0.92) and 47±9kJmol−1 (R 2 =0.96) for o-cresol and 2-chlorophenol, respectively. However, when using just [TOCeff], the obtained E ACT values were not in the range of the values reported in the literature and had smaller regression coefficients. Moreover, the calibration with just [TOCeff] presented a high correlation between the obtained rate constants, whereas the calibration with [TOCeff] and [TOC[A]] was statistically more reliable. As example, the D-criterion values are three to six times larger for the calibration made with ([TOCeff] and [TOC[A]] than for the calibration made only with [TOCeff], in the framework of OED/PE criteria, this is related to minimisation of the geometric mean of the identification errors. [Copyright &y& Elsevier]

A comparative study between a classic and a wireless electrochemical promotion experiment was undertaken as a tool towards the better understanding of both systems. The catalytic modification of a platinum catalyst for ethylene oxidation was studied. The catalyst was supported on yttria-stabilised-zirconia (YSZ), a known pure oxide ion conductor, for the classic experiment and La0.6Sr0.4Co0.2Fe0.8O3–δ—a mixed oxide ion electronic conductor—was used for the wireless experiment. The two systems showed certain similarities in terms of the reaction classification (in both cases electrophobic behaviour was observed) and the promotion mechanism. Significant difference was observed in the time scales and the reversibility of the induced rate modification. [ABSTRACT FROM AUTHOR]

Abstract: Two contrasting parallel tectonic sutures can be recognised through the Yunnan–Thailand region of mainland Southeast Asia; they are sutures of the Devonian–Triassic Palaeo-Tethys Ocean and a Permian back-arc basin. The Changning–Menglian and Inthanon suture zones are regarded as the Palaeo-Tethys Suture Zone. The Jinghong–Nan–Sra Kaeo suture is regarded as a closed back-arc basin. The Sukhothai Zone is no longer treated as a part of the Sibumasu Terrane, but is defined as the core part of the Permian island-arc system developed on the western margin of the Indochina Terrane. Two tectonic events are interpreted from the parallel sutures; a Late Permian collapse of the back-arc basin and a mid-Triassic collision of Sibumasu to the Sukhothai Arc of Indochina (=closure of the Palaeo-Tethys). The Early–early Middle Triassic thermotectonism of Vietnam as linked to the Indosinian orogeny by some authors is incompatible with the suggested timing of Sibumasu collision, but instead it is temporally closer to the back-arc compression of western Indochina. [Copyright &y& Elsevier]

Abstract: A membrane reactor module consisting of four gas-tight hollow fibre membranes made of the mixed ionic-electronic conducting perovskite La0.6Sr0.4Co0.2Fe0.8O3− δ has been tested for oxygen permeation in the temperature range of 650–1000°C with air on one side and helium on the other. The module was operated under gradientless gas-phase conditions and in the absence of mass transfer limitations at lower temperatures. Also at lower temperature the rate-determining step for oxygen permeation was found to be oxygen reduction with the oxygen permeation performance of the module being significantly enhanced by deposition of a porous platinum catalyst film onto the air-side of the membranes. A stable but mass transfer limited flux of 0.56μmolcm−2 s−1 (0.73mlSTPcm−2 min−1) was achieved after a period of 4 days of operation at 1000°C and continued at this rate for a further 4 days. A non-mass transfer limited flux of ca 0.14μmolcm−2 s−1 was obtained at 800°C. The membrane module was operated for 500h before the onset of significant leakage. Post operation qualitative analysis indicated localised changes in the stoichiometry of the membranes with no discernable trend, quantitative analysis on the other hand revealed that the perovskite had retained its starting composition. Post-operation analysis of the membranes revealed the presence of sulfur in the form of sulfates of strontium, cobalt and calcium and a change of surface microstructure for both the air- and lumen-side membrane surfaces. Possible sources of this sulfur contamination are: the glass-ceramic sealing material employed, the helium sweep gas and atmospheric sulfur dioxide. This contamination may contribute to the decrease in the long-term oxygen permeation rates. The metal cation stoichiometry of the perovskite showed changes in localised areas of the membranes following oxygen permeation studies. [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 article reports on various factors affecting environment in Bangladesh. Natural resources of Bangladesh include water, land, fisheries, forests and wildlife. The rapidly increasing population of Bangladesh places immense pressure on these natural resources and on the environment. Human health problems related to the environment are primarily due to contaminated ground and surface waters. The various contributory factors to environmental stress and degradation in Bangladesh are intense population pressure, industrial pollution, unsustainable land use and energy consumption, urbanization, agricultural intensification and natural hazards.

A new Middle Permian locality in northern Johore, Peninsular Malaysia, yields a small-sized, but compositionally unique, brachiopod fauna consisting of eight species: Pseudoleptodus sp., Caricula cf. salebrosa Grant, Neochonetes (Nongtaia) aff. arabicus (Hudson & Sudbury), Karavankina sp., Transennatia cf. insculpta (Grant), Hustedia sp., Orthothetina sp., and martiniid indet. The first four genera are new records for Malaysia; in particular, the rare taxa Pseudoleptodus and Caricula characterize the fauna. The brachiopods occur together with the ammonoid Agathiceras sp., the nautiloid Foordiceras? sp., bivalves, and crinoid stems. The locality belongs to the East Malaya terrane of the Cathaysian biotic region, but some affinities to species of the Sibumasu province are recognized. The Malaysian forms of Pseudoleptodus, Caricula and Transennatia are similar to those of the Ratburi Limestone (southern Thailand). A Roadian-early Wordian age is interpreted for the Johore fauna. The similarity of brachiopods reported here with those from the Ratburi Limestone suggests that there was species interchange or one-way migration between shallow waters of East Malaya and Sibumasu across the main Palaeo-Tethys. The Tethyan seaway between the two terranes must have been narrower than previously interpreted by some authors to allow such faunal traffic during the Roadian-Wordian time period. [ABSTRACT FROM AUTHOR]

A simple model to describe rate changes during the reversible electrochemical promotion of supported metal catalysts has been formulated. Polarisation of the interface between the ion-conducting support and the metal modifies the electron extraction potential of the metal as a result of the spillover of ionic oxygen species. By considering a simple reaction mechanism that involves a charged transition state and accounting for the effect of long-range electrostatic interactions, it is possible to express reaction rates as a function of applied overpotential. It is shown that under certain conditions reaction rates are predicted to increase on application of both negative and positive overpotentials, in agreement with some experimental studies (e.g. Refs. [Catal. Today 11 (1992) 303; J. Catal. 159 (1996) 189]), as a result of electron donation and acceptance from both the metal catalyst and the surface O/O2− redox couple. [Copyright &y& Elsevier]

The Mariana Trough, a relatively simple intra-oceanic back-arc basin, is ideal for investigating magmatic processes and mantle-crust interaction in a subduction setting. We present new major- and trace element compositions for 31 basaltic lava and glass samples from the Mariana Trough back-arc spreading center. The studied lavas include phenocrysts of plagioclase, olivine and pyroxene. Major element compositions show that these lavas range from tholeiitic basalt to basaltic andesite, and belong to a sub-alkali tholeiitic series produced by fluid-influenced fractional crystallization of primary basaltic melts. Trace element compositions show that these lavas are transitional between typical normal mid-ocean ridge basalts (MORB) and island arc basalt (IAB), and are enriched in large ion lithophile elements (LILEs) and light rare earth elements (LREEs). Trace element ratios, e.g., Ba/Th, Pb/Ce, Th/Nd, La/Sm, Th/Nb, Ba/Nb and Th/Nb, indicate that the mantle from which these lavas were derived underwent modification resulting from the addition of multiple subduction components. Some typical trace element ratios (e.g., Ba/Nb- total subduction component, Ba/Th- shallow subduction, and Th/Nb-deep subduction component) from our new data and the literature suggest that a latitudinal variation exists in addition to subduction components, and indicates a more complex and heterogeneous distribution of subduction components in the Mariana back-arc region. We suggest that, (1) compared to back-arc locations at 18° N and 15.5° N, lavas from back-arc locations at 17° N indicate higher levels of modification by hydrous fluid released from the subducted slab, and (2) compared to back-arc locations at 17° N and 15.5° N, petrogenesis of lavas from back-arc locations at 18° N indicates a greater influence of sediment melt. [ABSTRACT FROM AUTHOR]

This article presents a discussion of labor and environmental issues in South Asia. It is believed that governments in Asian countries, in their drive to be internationally competitive, have downplayed two key areas of labor and environmental standards. The developed countries pressurize them to adopt tighter standards regarding the issues like child labor, health and safety features of the workplace and labor rights. Their real motivation is protectionism, but they are accused of effecting the international market in their own interest. The article also reports on a workshop which debated these issues in the context of Bangladesh, a poor Asian country. It was organized by Australia-University of New England.

High‐performance nanoparticle platforms can drive catalysis progress to new horizons, delivering environmental and energy targets. Nanoparticle exsolution offers unprecedented opportunities that are limited by current demanding process conditions. Unraveling new exsolution pathways, particularly at low‐temperatures, represents an important milestone that will enable improved sustainable synthetic route, more control of catalysis microstructure as well as new application opportunities. Herein it is demonstrated that plasma direct exsolution at room temperature represents just such a step change in the synthesis. Moreover, the factors that most affect the exsolution process are identified. It is shown that the surface defects produced initiate exsolution under a brief ion bombardment of an argon low‐pressure and low‐temperature plasma. This results in controlled nanoparticles with diameters ≈19–22 nm with very high number densities thus creating a highly active catalytic material for CO oxidation which rivals traditionally created exsolved samples. [ABSTRACT FROM AUTHOR]

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]

Highlights: [•] Sodium added on Pt/YSZ system affects catalytic and electrocatalytic properties. [•] Proposed model considers work-function changes by promoter species independently. [•] High Na coverage causes interaction among promoter species and reaction components. [•] Reaction changes from electrophilic to volcano and electrophobic at high Na coverage. [ABSTRACT FROM AUTHOR]

Abstract: It has been demonstrated in our previous studies that in order for greater methane conversion and less coke-formation, a higher oxygen permeation rate through the outer oxygen separation layer of a functional dual-layer ceramic hollow fibre membrane is needed. Besides new membrane materials with higher oxygen permeability, another way of improving oxygen permeation is to reduce the separation layer thickness, although this strategy is limited by the characteristic thickness, L c , where bulk diffusion and surface oxygen exchange are both important. As a result, a series of La0.80Sr0.20MnO3−δ (LSM)-Scandia(10%)-Stabilized-Zirconia (ScSZ)/ScSZ-NiO functional dual-layer hollow fibres (DL-HF) with an outer oxygen separation layer thickness between approximately 8.0 and 72.4μm were fabricated in this study, by using the single-step co-extrusion and co-sintering process. The effects of separation layer thickness on oxygen permeation and mechanical strength were investigated. The oxygen permeation of the LSM-ScSZ separation layer is more likely to be controlled by surface exchange at higher temperatures, and changes to mixed control by both bulk diffusion and surface exchange at lower temperatures. A thicker separation layer also results in a thinner catalytic substrate layer, and subsequently decreases the mechanical strength of the dual-layer hollow fibre membrane. [Copyright &y& Elsevier]

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 effect of spillover processes on the activity of a catalyst system consisting of a mixed oxygen ion and electronic conducting support La0.6Sr0.4Co0.2Fe0.8O3− δ and a metal catalyst (Pt) were investigated. Two types of model single-pellet catalysts were used employing Pt deposited on both sides of a dense LSCF disc pellet. One of these single pellets employed highly disperse, physically non-continuous Pt, in contrast to studies on electrochemical promotion, while the other used a low dispersion continuous film. Driving forces for promoter migration were controlled through the manipulation of the oxygen chemical potential difference across the membrane. Catalyst rate modification was observed in all cases. However, it was found that there is a complex relationship between the rate modification, the driving forces for spillover and the geometrical arrangement of the catalyst on the support (i.e. catalyst dispersion). [Copyright &y& Elsevier]

Abstract: The suitability of nickel electroless plating for anode deposition on electrolyte-supported solid oxide fuel cells (SOFCs) based on yttrium-stabilised zirconia (YSZ) has been studied. A deposition technique was developed and characterisation is presented with respect to microstructure, strength and performance of the resultant anode. The study was carried out on YSZ disk-shaped pellets sintered at different temperatures ranging from 1000 °C to 1400 °C with analysis of the influence of sintering temperature on the Ni–YSZ interface microstructure and fuel cell performance. Lower pre-sintering temperature resulted in higher Ni penetration into the YSZ matrix, forming a graded anode and improving the anode–electrolyte interfacial strength. The optimised electrode showed good mechanical stability under redox cycling which resulted in an enhancement of electrode porosity. Complete fuel cells were tested at 800°C with 5% H2 and air after a porous La0.2Sr0.8Co0.8Fe0.2O3− δ (LSCF) cathode layer had been deposited by slurry coating. The higher Ni penetration on YSZ substrates pre-sintered at low temperature resulted in an improvement of one order of magnitude of power output compared to a cell in which a metal Ni anode was coated over a fully dense (i.e. high pre-sintering temperature) electrolyte surface. [Copyright &y& Elsevier]

Abstract: Wet air oxidation (WAO) was investigated as a suitable precursor for the biological treatment of industrial wastewaters that contained high concentrations of phenol, o-cresol or 2-chlorophenol. Two hours WAO semi-batch experiments were conducted at 2 and 9bar of oxygen partial pressure () and at 215, 240 and 265°C with total organic carbon (TOC) abatement up to 86%. The influence of hydroxyl-, methyl- and chloride ring substitution on the oxidation mechanism of aromatic compounds was established. Also, the readily biodegradable COD fraction (%CODRB) of the WAO effluents was found by respirometric techniques. The maximum %CODRB was 24% for phenol WAO at 265°C and 9bar of , 10% for o-cresol WAO at 265°C and 9bar of and 19% for 2-chlorophenol WAO at 215°C and 2bar of . These results allow comparison of whether or not the WAO effluents were suitable for a conventional activated sludge plant with non-acclimated biomass. Also, the results were compared to those obtained from a previous study for the same model compounds but using catalytic WAO (CWAO) with activated carbon (AC) as a catalyst [1]. This comparison allows us to establish whether or not the WAO effluents were less biodegradable or had more refractory intermediates than CWAO effluents. [Copyright &y& Elsevier]

Abstract: A novel configuration for the in situ control of the catalytic activity of a polycrystalline Pt catalyst supported on a mixed ionic electronic conducting (MIEC) substrate is investigated. The modification of the catalytic activity is achieved by inducing the reverse spillover of oxygen promoting species from the support onto the catalyst surface, thus modifying the chemisorptive bond energy of the gas phase adsorbed reactants. This phenomenon is known as Electrochemical Promotion of Catalysis (EPOC). In this work we investigate the use of a wireless system that takes advantage of the mixed ionic electronic conductivity of the catalyst support (internally short-circuiting the system) in a dual chamber reactor. In this wireless configuration, the reaction takes place in one chamber of the membrane reactor while introduction of the promoting species is achieved by the use of an appropriate sweep gas (and therefore control of the oxygen chemical potential difference across the membrane) on the other chamber. Experimental results have shown that the catalytic rate can be enhanced by using an oxygen sweep, while a hydrogen sweep can reverse the changes. Total rate enhancement ratios of up to 3.5 were measured. [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]

The wet air oxidation (WAO) and ultrasound irradiation of sodium dodecylbenzene sulfonate in water was investigated. Heterogeneous catalysts such as a mixed copper-zinc oxide and noble metals, namely platinum, palladium and ruthenium, generally improved the efficiency of the respective uncatalysed process. The performance of sonochemical treatment, although less effective than WAO at high organic concentrations, may improve by a Fenton-like reaction mechanism on the addition of ferrous ions. [ABSTRACT FROM AUTHOR]

The age and timing of the Permian-Triassic mass extinction have been difficult to determine because zircon populations from the type sections are typically affected by pervasive lead loss and contamination by indistinguishable older xenocrysts. Zircons from nine ash beds within the Shangsi and Meishan sections (China), pretreated by annealing followed by partial attack with hydrofluoric acid, result in suites of consistent and concordant uranium/lead (U/Pb) ages, eliminating the effects of lead loss. The U/Pb age of the main pulse of the extinction is 252.6 ± 0.2 million years, synchronous with the Siberian flood volcanism, and it occurred within the quoted uncertainty. [ABSTRACT FROM AUTHOR]

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]

Supported bimetallic nanoparticles used for various chemical transformations appear to be more appealing than their monometallic counterparts, because of their unique properties mainly originating from the synergistic effects between the two different metals. Exsolution, a relatively new preparation method for supported nanoparticles, has earned increasing attention for bimetallic systems in the past decade, not only due to the high stability of the resulting nanoparticles but also for the potential to control key particle properties (size, composition, structure, morphology, etc.). In this review, we summarize the trends and advances on exsolution of bimetallic systems and provide prospects for future studies in this field. [ABSTRACT FROM AUTHOR]

Exsolution of surface and bulk nanoparticles in perovskites has been recently employed in chemical looping methane partial oxidation because of the emergent materials' properties such as oxygen capacity, redox stability, durability, coke resistance and enhanced activity. Here we attempt to further lower the temperature of methane conversion by complementing exsolution with infiltration. We prepare an endo/exo-particle system using exsolution and infiltrate it with minimal amount of Rh (0.1 wt%) in order to functionalize the surface and induce low temperature activity. We achieve a temperature decrease by almost 220 °C and an increase of the activity up to 40%. We also show that the initial microstructure of the perovskite plays a key role in controlling nanoparticle anchorage and carbon deposition. Our results demonstrate that microstructure tuning and surface functionalization are important aspects to consider when designing materials for redox cycling applications. [ABSTRACT FROM AUTHOR]

Unitary Association Method (UAM) analyses of conodont faunas from 28 sections spanning the biggest Phanerozoic end-Permian mass extinction and significant global environmental and ecosystem perturbations during the succeeding Early Triassic are presented. Based on 72 conodont species, 26 Unitary Association Zones (UAZs) are established for the latest Permian to earliest Middle Triassic of South China. These UAZs provide quantitative high-resolution tools to correlate sequences in the Early Triassic of South China and to compare and test high-resolution conodont biostratigraphy based on interval conodont zones developed over the past three decades. Our quantitative analyses provide insights on ongoing debates relating to the First Appearance Datum (FAD) of the conodont Hindeodus parvus which is used to place and subsequently correlate the "Golden Spike" defining the base of the Triassic (Permian-Triassic Boundary) at the base of Bed 27c at the GSSP Meishan D Section. Previous proposals that suggested potential earlier occurrences of H. parvus below its FAD at Meishan section are not supported by our results. In deep water sections, the First Occurrence (FO) of H. parvus lies at the base of UAZ 5 at the Bianyang section while it lies within UAZ 6 at the Meishan section. This indicates that the earliest occurrence of H. parvus in South China is in the Bianyang section but this conclusion needs further testing due to the reliance on "spot" data by the UAM. Anomalously high occurrences of Hindeodus in the Mingtang section (close to the Bianyang section) further suggests that the Bianyang-Mingtang area may have provided a temporally extended habitable zone for anchignathodontid conodonts. Stage boundaries currently proposed or established using interval conodont zones locate within or between UAZs and are difficult to correlate with carbon isotope curves. UAZs are useful in helping to define GSSPs by recognizing which correlations are most robust and in the selection of the most appropriate species and level for GSSPs. [ABSTRACT FROM AUTHOR]

Composite materials consisting of metal and metal oxide phases are being researched intensively for various energy conversion applications where they are often expected to operate under redox conditions at elevated temperature. Understanding of the dynamics of composite evolution during redox cycling is still very limited, yet critical to maximising performance and increasing durability. Here we track the microstructural evolution of a single composite particle over 200 redox cycles for hydrogen production by chemical looping, using multi-length scale X-ray computed tomography. We show that redox cycling triggers a centrifugal redispersion of the metal phase and a centripetal clustering of porosity, both seemingly driven by the asymmetric nature of oxygen exchange in composites. Initially, the particle develops a large amount of internal porosity which boosts activity, but on the long term this facilitates structural and compositional reorganisation and eventually degradation. These results provide valuable insight into redox-driven microstructural changes and also for the design of new composite materials with enhanced durability. [ABSTRACT FROM AUTHOR]

Particles dispersed on the surface of oxide supports have enabled a wealth of applications in electrocatalysis, photocatalysis, and heterogeneous catalysis. Dispersing nanoparticles within the bulk of oxides is, however, synthetically much more challenging and therefore less explored, but could open new dimensions to control material properties analogous to substitutional doping of ions in crystal lattices. Here we demonstrate such a concept allowing extensive, controlled growth of metallic nanoparticles, at nanoscale proximity, within a perovskite oxide lattice as well as on its surface. By employing operando techniques, we show that in the emergent nanostructure, the endogenous nanoparticles and the perovskite lattice become reciprocally strained and seamlessly connected, enabling enhanced oxygen exchange. Additionally, even deeply embedded nanoparticles can reversibly exchange oxygen with a methane stream, driving its redox conversion to syngas with remarkable selectivity and long term cyclability while surface particles are present. These results not only exemplify the means to create extensive, self‐strained nanoarchitectures with enhanced oxygen transport and storage capabilities, but also demonstrate that deeply submerged, redox‐active nanoparticles could be entirely accessible to reaction environments, driving redox transformations and thus offering intriguing new alternatives to design materials underpinning several energy conversion technologies. [ABSTRACT FROM AUTHOR]

Metallic nanoparticles exsolved at the surface of perovskite oxides have been recently shown to unlock superior catalytic activity and durability towards various chemical reactions of practical importance. For example, for the CO oxidation reaction, exsolved Ni nanoparticles in oxidised form exhibit site activities approaching those of noble metals. This is of particular interest for the prospect of replacing noble metals with earth-abundant metal/metal oxide catalysts in the automotive exhaust control industry. Here we show that for the CO oxidation reaction, the functionality of exsolved Ni nanoparticles can be further improved when Fe is co-exsolved with Ni, as Fe–Ni alloy nanoparticles, eventually forming mixed oxide nanoparticles. As compared to the Ni nanoparticles, the alloy nanoparticles exhibit higher site activities, greatly improved durability over 170 h of continuous testing and increased tolerance towards sulphur-based atmospheres. Similarly to the single metal nanoparticles, the alloys demonstrate outstanding microstructural stability and high tolerance towards coking. These results open additional directions for tailoring the activity and durability of exsolved materials for the CO oxidation reaction and beyond. [ABSTRACT FROM AUTHOR]

Graphical abstract Ni x Cu 1- x Al 2 O 4 spinel solution suppresses carbon deposition during the chemical looping oxidation of CH 4 by Ni-Cu-Al 2 O 3 oxygen carriers. The Ni-Cu-Al 2 O 3 oxygen carriers also contain highly active redox-active lattice oxygen compared to a single metal oxide (CuO or NiO) supported on Al 2 O 3. Highlights • Ni-Cu-Al 2 O 3 oxygen carriers with stable performance over 100 redox cycles. • Fully characterized phase interactions in Ni-Cu-Al 2 O 3 oxygen carriers. • CuO-NiO interaction promotes lattice oxygen activity. • Ni 1- x Cu x Al 2 O 4 spinel solid solution is resistant against carbon deposition. Abstract Chemical looping processes present great potentials to achieve carbon capture and fuel conversion with high thermodynamic efficiencies. Well-known applications of chemical looping include combustion and methane reforming, where phase interactions in oxygen carriers play important roles in determining the process performance. In this study, we systematically investigate the interactions between various phases in Ni-Cu-Al 2 O 3 mixed oxides oxygen carriers, which were prepared from layered double hydroxides precursors, synthesized hydrothermally using urea and metal nitrates. It appears that the addition of 32–45 wt% Al 2 O 3 was sufficient to prevent sintering effects over 100 redox cycles at 800 °C, 1 atm, using methane as the fuel. The oxide phases and their compositions were determined using a set of complementary analytical techniques, allowing us to establish relationships between (i) the compositions of the mixed oxides, (ii) the chemical activity of the various types of lattice oxygen present and (iii) the distributions of gaseous products of chemical looping methane oxidation. We found that the mutual doping between NiO and CuO leads to enhanced lattice oxygen activities, whilst the solid solution of NiAl 2 O 4 and CuAl 2 O 4 leads to reduced lattice oxygen activity in the spinel phase, which also turns out to be particularly resistant to carbon deposition. The generality of the composition – activity - performance relationship is demonstrated by the successful prediction of the product distributions of methane oxidation based on solely the elemental compositions of the oxygen carriers. These findings enable the rational formulation of Ni-Cu-Al 2 O 3 oxygen carriers for methane conversion with precise control of product selectivity. [ABSTRACT FROM AUTHOR]

Additive manufacturing, likewise known as 3-dimensional (3D) printing and rapid prototyping, has the ability to create almost any geometrically complex shape or feature in a range of materials across different scales. It has found its applications in various areas, such as medicine (bioprinting), art, manufacturing and engineering. On the other hand, its use in separation membrane engineering is relatively new. The use of additive manufacturing techniques could provide more control towards the design of separation membrane systems and offers novel membrane preparation techniques that are able to produce membranes of different shapes, types and designs which cannot be made using conventional techniques such as phase inversion or sintering. Here we provide key background information on 3D printing technologies and applications in membrane engineering; a discussion of the potential and limitations of current 3D printing technologies for membrane engineering and future aspects of the technology. Due to the potential benefits of 3D printing in membrane manufacturing, in particular the unprecedented control over membrane architecture the technique could allow, the use of 3D printing in membrane systems should see significant growth in the near future. [ABSTRACT FROM AUTHOR]

The United Kingdom has a vast scientific base across the entire Hydrogen and Fuel Cell research landscape, with a world class academic community coupled with significant industrial activity from both UK-based Hydrogen and Fuel Cell companies and global companies with a strong presence within the country. The Hydrogen and Fuel Cell (H2FC) SUPERGEN Hub, funded by the Engineering and Physical Sciences Research Council (EPSRC), was established in 2012 as a five-year programme to bring the UK's H2FC research community together. Here we present the UK's current Hydrogen and Fuel Cell activities along with the role of the H2FC SUPERGEN Hub. [ABSTRACT FROM AUTHOR]

Tropical Southeast (SE) Asia harbors extraordinary species richness and in its entirety comprises four of the Earth's 34 biodiversity hotspots. Here, we examine the assembly of the SE Asian biota through time and space. We conduct meta-analyses of geological, climatic, and biological (including 61 phylogenetic) data sets to test which areas have been the sources of long-term biological diversity in SE Asia, particularly in the pre-Miocene, Miocene, and Plio-Pleistocene, and whether the respective biota have been dominated by in situ diversification, immigration and/or emigration, or equilibrium dynamics. We identify Borneo and Indochina, in particular, as major “evolutionary hotspots” for a diverse range of fauna and flora. Although most of the region's biodiversity is a result of both the accumulation of immigrants and in situ diversification, within-area diversification and subsequent emigration have been the predominant signals characterizing Indochina and Borneo's biota since at least the early Miocene. In contrast, colonization events are comparatively rare from younger volcanically active emergent islands such as Java, which show increased levels of immigration events. Few dispersal events were observed across the major biogeographic barrier of Wallace's Line. Accelerated efforts to conserve Borneo's flora and fauna in particular, currently housing the highest levels of SE Asian plant and mammal species richness, are critically required. [ABSTRACT FROM AUTHOR]