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Foliar stable nitrogen (N) isotopes (δ 15 N) generally reflect N availability to plants and have been used to infer about changes thereof. However, previous studies of temporal trends in foliar δ 15 N have ignored the influence of confounding factors, leading to uncertainties on its indication to N availability. In this study, we measured foliar δ 15 N of 1811 herbarium specimens from 12 plant species collected in southern China forests from 1920 to 2010. We explored how changes in atmospheric CO 2 , N deposition and global warming have affected foliar δ 15 N and N concentrations ([N]) and identified whether N availability decreased in southern China. Across all species, foliar δ 15 N significantly decreased by 0.82‰ over the study period. However, foliar [N] did not decrease significantly, implying N homeostasis in forest trees in the region. The spatiotemporal patterns of foliar δ 15 N were explained by mean annual temperature (MAT), atmospheric CO 2 ( P CO 2 ), atmospheric N deposition, and foliar [N]. The spatiotemporal trends of foliar [N] were explained by MAT, temperature seasonality, P CO 2 , and N deposition. N deposition within the rates from 5.3 to 12.6 kg N ha -1  year -1 substantially contributed to the temporal decline in foliar δ 15 N. The decline in foliar δ 15 N was not accompanied by changes in foliar [N] and therefore does not necessarily reflect a decline in N availability. This is important to understand changes in N availability, which is essential to validate and parameterize biogeochemical cycles of N., (© 2022 John Wiley & Sons Ltd.)

Microporous aluminophosphates are promising materials for gas separation, but their industrial applications are still challenging due to the permeability-selectivity "trade-off" behavior. A new approach is now reported by the addition of single novel template N, N -diisopropylethylamine (DIPEA) into the gel precursor to prepare the pure AlPO-18 membrane with both high permeance and selectivity. It was identified that the AlPO-18 membrane possessed small plate-like crystals on support surface. The single and mixed CO 2 /CH 4 and N 2 /CH 4 gas separations were measured. The best membrane exhibited high CO 2 and N 2 permeances of 9.2, 0.91 × 10−7 mol m−2 s−1∙Pa−1 under the two-component gas mixture, and the mixture selectivities in CO 2 /CH 4 and N 2 /CH 4 were 93 and 6.0 at 303 K and 0.2 MPa, respectively. This strategy not only demonstrated a potential zeolite membrane material for gas separation but also furnished ideas for the preparation of high permeable thin films. [Display omitted] • High gas separation performance AlPO-18 membrane was obtained with DIPEA template. • The effect of DIPEA content was investigated. • The AlPO-18 membrane showed the CO 2 /CH 4 separation performance of 93 with the CO 2 permeance of 9.2 × 10−7 mol m−2 s−1∙Pa−1. [ABSTRACT FROM AUTHOR]

A rapid and facile strategy for AEI type AlPO-18 molecular sieves preparation was hydrothermally processed by dual templates of TEAOH (tetraethyl ammonium hydroxide) and low-cost DIPEA (N, N-diisopropylethylamine). Pure and high crystallinity AlPO-18 molecular sieve with the crystal size of 2 μm and the aspect ratio about 20 were obtained in a short period of 1 h under the dual-template strategy. The effect of single and binary templates on the growth process of AlPO-18 molecular sieve was compared in detail. TEAOH is conducive to the pure phase AEI formation since a long synthesis time is needed. DIPEA favors to the rapid formation of AEI structure, however the sole DIPEA template promotes to form the AFI type AlPO-5 impurities. The combined templates TEAOH/DIPEA work synergistically, and the 13C MAS NMR results showed that both the TEAOH and DIPEA templates were occluded in micropore space of AlPO-18 molecular sieves. In addition, the adsorption isotherms of CO 2 , CH 4 and N 2 on the samples synthesized by dual-template for 1 h were tested and compared with other AlPO-18 molecular sieves reported in the literature. The results showed that the current AlPO-18 molecular sieve is expected to be used as adsorbent for light gas separation. [Display omitted] • AlPO-18 molecular sieve with high crystallinity was synthesized by a dual-template strategy. • Successful rapid synthesis by conventional hydrothermal method in 1 h. • Investigated the effect of template strategies on AlPO-18 synthesis. • AlPO-18 molecular sieve is expected to be used as absorbent for light gas separation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Photo-thermal-magnetic three-field coupling for enhanced CO 2 photo-reduction. • Nickel foam was used as nickel source and catalyst support. • 0.01 wt% Cu/Cu 2 O/HNF exhibited the best catalytic activity and CH 4 selectivity. • The heat of the reaction system came from magnetic-thermal and photo-thermal effects. Aiming at the bottleneck of thermodynamics, kinetics and reaction systems in photothermal catalytic CO 2 reduction conversion, a three-field coupling method based on the efficient utilization of solar energy and the application of a photo-thermal-magnetic three-field was proposed to achieve efficient and highly selective CO 2 conversion. The composite monolithic catalyst with three field response functions and multiple active reaction interfaces was prepared by using photoactive copper supported by nickel foam. The effect of an external alternating magnetic field on photocatalytic CO 2 reduction was studied using a range between 0.005 and 0.1 wt% Cu/Cu 2 O/Ni(OH) 2 /NF as catalysts. The results showed that 0.01 wt% Cu/Cu 2 O/Ni(OH) 2 /NF exhibited the best catalytic activity and CH 4 selectivity under alternating magnetic field enhanced photocatalysis. The main products were CO (6.76 μmol g−1) and CH 4 (167 μmol g−1). The selectivity of CH 4 was 96.1%. The yields of CH 4 using this method were 11 and 6 times higher than the yields obtained with photocatalysis (14.58 μmol g−1) and magnetic-thermal catalysis (26.75 μmol g−1), respectively. According to the analysis of temperature measurements and electrochemical measurements, the surface temperature of the three-field coupled catalyst reaches about 230 °C. Applying an alternating magnetic field can effectively reduce the recombination of photogenerated electron holes. Alternating magnetic field enhanced photocatalytic CO 2 reduction conversion provides a new and promising method for the efficient conversion and utilization of solar energy. [ABSTRACT FROM AUTHOR]