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Poly(ether-b-amide) (Pebax11657)/polyacrylonitrile (PAN) composite hollow fiber membranes for a potential use in CO2/CH4 separation were prepared by a new continuous coating method, referred to as cross-flow filtration. This technique allows to obtain the simultaneous coating of a large number of fibers, facilitating the scale-up. The dense layer was deposited in the lumen of the fibers allowing the coating of all the fibers in a single step. The coating on the inner surface of the fibers avoids the negative effects such as sticking or accidental mechanical damages occurring in the case of external coating. The membrane preparation was optimized by modulating different parameters. The optimal range of viscosity and concentration of the polymer solution to obtain a selective homogeneous Pebax1 layer was identified. The presence of the Pebax11657 dense layer was confirmed by IR spectroscopy and the morphology of the composite membranes was observed by SEM analysis. The gas separation performance of the membrane modules was determined by single gas permeation measurements. A preliminary optimization yielded membranes with PCO2 = 5x 103 (m3m2 h1 bar1), aCO2=CH4 = 18 equal to that of the neat dense polymer. The PEBAX1/PAN hollow fibers modules are potentially useful for application in the purification of biogas.

ABSTRACTIntraguild interactions among carnivores have long held the fascination of ecologists. Ranging from competition to facilitation and coexistence, these interactions and their complex interplay influence everything from species persistence to ecosystem functioning. Yet, the patterns and pathways of such interactions are far from understood in tropical forest systems, particularly across countries in the Global South. Here, we examined the determinants and consequences of competitive interactions between dholes Cuon alpinus and the two large felids (leopards Panthera pardus and tigers Panthera tigris) with which they most commonly co‐occur across Asia. Using a combination of traditional and novel data sources (N = 118), we integrate information from spatial, temporal, and dietary niche dimensions. These three species have faced catastrophic declines in their extent of co‐occurrence over the past century; most of their source populations are now confined to Protected Areas. Analysis of dyadic interactions between species pairs showed a clear social hierarchy. Tigers were dominant over dholes, although pack strength in dholes helped ameliorate some of these effects; leopards were subordinate to dholes. Population‐level spatio‐temporal interactions assessed at 25 locations across Asia did not show a clear pattern of overlap or avoidance between species pairs. Diet‐profile assessments indicated that wild ungulate biomass consumption by tigers was highest, while leopards consumed more primate and livestock prey as compared to their co‐predators. In terms of prey offtake (ratio of wild prey biomass consumed to biomass available), the three species together harvested 0.4–30.2% of available prey, with the highest offtake recorded from the location where the carnivores reach very high densities. When re‐examined in the context of prey availability and offtake, locations with low wild prey availability showed spatial avoidance and temporal overlap among the carnivore pairs, and locations with high wild prey availability showed spatial overlap and temporal segregation. Based on these observations, we make predictions for 40 Protected Areas in India where temporally synchronous estimates of predator and prey densities are available. We expect that low prey availability will lead to higher competition, and in extreme cases, to the complete exclusion of one or more species. In Protected Areas with high prey availability, we expect intraguild coexistence and conspecific competition among carnivores, with spill‐over to forest‐edge habitats and subsequent prey‐switching to livestock. We stress that dhole–leopard–tiger co‐occurrence across their range is facilitated through an intricate yet fragile balance between prey availability, and intraguild and conspecific competition. Data gaps and limitations notwithstanding, our study shows how insights from fundamental ecology can be of immense utility for applied aspects like large predator conservation and management of human–carnivore interactions. Our findings also highlight potential avenues for future research on tropical carnivores that can broaden current understanding of intraguild competition in forest systems of Asia and beyond.

This archive includes a minimal dataset needed to reproduce the analysis as well as a table (CSV) and spatial polygons (ESRI shapefile) of the resulting output from the publication: Hoecker, T.J., S. A. Parks, M. Krosby & S. Z. Dobrowski. 2023. Widespread exposure to altered fire regimes under 2°C warming is projected to transform conifer forests of the Western United States. Communications Earth and Environment. Publication abstract: Changes in wildfire frequency and severity are altering conifer forests and pose threats to biodiversity and natural climate solutions. Where and when feedbacks between vegetation and fire could mediate forest transformation are unresolved. Here, for the western U.S., we used climate analogs to measure exposure to fire-regime change; quantified the direction and spatial distribution of changes in burn severity; and intersected exposure with fire-resistance trait data. We measured exposure as multivariate dissimilarities between contemporary distributions of fire frequency, burn severity, and vegetation productivity and distributions supported by a 2 °C-warmer climate. We project exposure to fire-regime change across 65% of western US conifer forests and mean burn severity to ultimately decline across 63% because of feedbacks with forest productivity and fire frequency. We find that forests occupying disparate portions of climate space are vulnerable to projected fire-regime changes. Forests may adapt to future disturbance regimes, but trajectories remain uncertain.

The optical and photovoltaic properties of Si NCs / SiC multilayers (MLs) are investigated using a membrane-based solar cell structure. By removing the Si substrate in the active cell area, the MLs are studied without any bulk Si substrate contribution. The occurrence is confirmed by scanning electron microscopy and light-beam induced current mapping . Optical characterization combined with simulations allows us to determine the absorption within the ML absorber layer, isolated from the other cell stack layers. The results indicate that the absorption at wavelengths longer than 800 nm is only due to the SiC matrix. The measured short-circuit current is significantly lower than that theoretically obtained from absorption within the ML absorber, which is ascribed to losses that limit carrier extraction. The origin of these losses is discussed in terms of the material regions where recombination takes place. Our results indicate that carrier extraction is most efficient from the Si NCs themselves, whereas recombination is strongest in SiC and residual a-Si domains . Together with the observed onset of the external quantum efficiency (EQE) at 700-800 nm, this fact is an evidence of quantum confinement in Si NCs embedded in SiC on device level.

Supporting data and code for review article: Sokol N.W., Whalen E.D., Kallenbach C., Pett-Ridge J., Georgiou K. The Global Distribution, Formation, and Fate of Mineral-Associated Soil Organic Matter Under a Changing Climate ��� A Trait-Based Perspective. Functional Ecology, 2022. We leveraged data from a global synthesis of soil fractionation measurements (DOI: 10.5281/zenodo.5987415). For this review article, we specifically focused on measurements of bulk and mineral-associated soil organic carbon concentrations (reported in units of gC/kg soil) and the proportion of bulk soil organic carbon that is mineral-associated (reported as a %). This subset also includes auxiliary data regarding climate and biome characteristics extracted from the synthesized papers; for more variables, see the original full dataset. K��ppen-Geiger climate zones were extracted from a georeferenced global database (using R package 'kgc' v1.0.0.2) with site coordinates, where available. Three files are provided in this repository: (1) data file, (2) metadata file, and (3) code for manuscript figures and summary statistics.

Commercial bakery products in the United States such as breads, rolls, frozen cakes, pies, pastries, cookies, and crackers consume over $870 million of energy annually. Energy efficiency measures can reduce the energy costs of significant energy processes and increase earnings predictability. This article summarizes key energy efficiency measures relevant to industrial baking. Case study data from bakeries and related facilities worldwide are used to identify savings and cost metrics associated with efficiency measures. While the focus of this paper is on U.S. bakeries, findings can be generalized to bakeries internationally. A discussion of energy management systems is provided and how energy efficiency measures savings can be sustained. Energy and plant managers at bakeries can use this information to cost-effectively reduce energy consumption while utilities and policy makers can apply the findings to energy efficiency program design.

AbstractWith growing demand for internationally traded biomass, the logistic operations required to economically move biomass from the field or forest to end‐ users have become increasingly complex. To design cost effective and sustainable feedstock supply chains, it is important to understand the economics, energy and greenhouse gas (GHG) emissions, their interdependencies, and the related uncertainties of the logistic process operations of international supply chains. This paper presents an approach to assessing lignocellulosic feedstock supply systems at the operational level. For this purpose, the Biomass Logistic Model (BLM) has been linked with the Geographic Information Systems‐based Biomass Intermodal Transportation Model (BIT‐UU) and extended with inter‐continental transport routes. Case studies of herbaceous and woody biomass, produced in the US Midwest and US Southeast, respectively, and shipped to Europe for conversion to Fischer‐Tropsch (FT) diesel are included to demonstrate how intermodal transportation and, in particular, overseas shipping integrates with the bioenergy supply chains. For the cases demonstrated, biomass can be supplied at 99 € Mg−1 to 117 € Mg−1 (dry) and converted to FT diesel at 19 € GJ−1 to 24 € GJ−1 depending on the feedstock type and location, intermediate (chips or pellets) and size of the FT diesel production plant. With the flexibility to change the design of supply chains as well as input variables, many alternative supply chain cases can be assessed. © 2014 Society of Chemical Industry and John Wiley & Sons, Ltd

Climatic niche evolution of disease-causing pathogens driving amphibian declines