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Membrane separation technology has become a very effective separation technology for CO2reduction, saving about 90% of energy consumption. However, the CO2separation performance of gas separation membranes is limited by the “trade-off” between permeance and selectivity in the separation process. Herein, g-C3N4-GO/Pebax-1657 MMMs (mixed matric membranes) were prepared by a solution casting method by combining graphene oxide (GO) nanosheets with g-C3N4nanosheets as composite fillers, and the membrane possesses excellent thermal stability and mechanical properties. Among them, GO nanosheets containing abundant functional groups were used to repair nonselective defects in g-C3N4nanosheets (amide bonds were formed between them). The prepared g-C3N4-GO0.30/Pebax MMM possesses excellent CO2separation performance (CO2permeance of 815.11 GPU and selectivity of 48.37 for CO2/N2separation; CO2permeance of 737.99 GPU and selectivity of 44.94 for CO2/CH4separation). This study provides theoretical and experimental guidance for the design and preparation of a practical CO2separation membrane.

Graphene was first employed to improve the mechanical properties of Nb/Nb5Si3composite, which is a critical candidate for the next-generation of high-temperature structural materials for aero-engines. Microstructures and mechanical properties of graphene reinforced Nb/Nb5Si3composites with interfacial nano-Nb4C3phase were systematically investigated. The graphene reinforced Nb/Nb5Si3composite with outstanding room temperature fracture toughness and compressive strength was fabricated successfully via spark plasma sintering. The microstructure of this composite changes from laminated morphology to uniformly distributed equiaxed microstructure, with the increase of fabrication temperature from 1450 °C to 1550 °C. The high compressive strength of graphene reinforced Nb/Nb5Si3composites is attributed to the load transfer of graphene, and this load transfer efficiency is strengthened due to the anchoring effect of the interfacial nano-scale Nb4C3phase. The high fracture toughness of this composite is attributed to the pull-out of graphene, as well as the crack deflection and crack bridging induced by graphene. The laminated architecture is also beneficial to improve fracture toughness because it can promote the minor deflection of cracks. The superior combination of strength and toughness of graphene reinforced Nb/Nb5Si3composites validates that our design strategy can successfully break through the strength-toughness trade-off. This study is expected to offer a new strategy and theoretical basis for the development of Nb/Nb5Si3composites with outstanding mechanical properties.

While disrupted lipid metabolism is a well-established risk factor for hypertension in animal models, the links between various lipidomic signatures and hypertension in human studies remain unclear. We aimed to examine associations between plasma lipidomic profiles and prevalence of hypertension among 2248 community-living Chinese aged 50–70 years. Hypertension was defined according to 2020 International Society of Hypertension global hypertension practice guidelines and 2018 Chinese guidelines. In total, 728 plasma lipidomic species were profiled using high-coverage targeted lipidomics. After multivariate adjustment, including lifestyle, body mass index, blood lipids, and sodium intake, 110 metabolites from nine lipidomic subclasses showed significant associations with hypertension, among which phosphatidylethanolamines (PEs) had the strongest association. Eleven lipidomic signals for hypertension risk were further identified from the nine subclasses, including PE(18:0/18:2) (OR per SD, 1.49; 95% confidence intervals, 1.30–1.69), phosphatidylcholine (PC) (18:0/18:2) (1.27; 1.13–1.43), phosphatidylserine (18:0/18:0) (1.24; 1.09–1.41), lysophosphatidylinositol (18:1) (1.17; 1.06–1.29), triacylglycerol (52:5) (1.38; 1.18–1.61), diacylglycerol (16:0/18:2) (1.42; 1.19–1.69), dihydroceramide (24:0) (1.25; 1.09–1.43), hydroxyl-sphingomyelins (SM[2OH])C34:1 (1.19; 1.07–1.33), lysophosphatidylcholine (20:1) (0.86; 0.78–0.95), SM(OH)C38:1 (0.87; 0.79–0.96), and PC (18:2/20:1) (0.84; 0.75–0.94). Principal component analysis also showed that a factor mainly containing specific PEs was positively associated with hypertension (1.20; 1.09–1.33). Collectively, our study revealed that disturbances in multiple circulating lipidomic subclasses and signatures, especially PEs, were significantly associated with the prevalence of hypertension in middle-aged and elderly Chinese. Future studies are warranted to confirm our findings and determine the mechanisms underlying these associations.

Wheat bran is the by-product of flour processing. Despite being nutritious, it is unsuitable for direct use in human consumption because of its palatability. It used to serve as animal feed. The study is aimed to use two wheat bran processing methods for producing the fine powder production which could be more conveniently used as the nutritious food with good palatability or as commercial fiber supplement product. The method I organically combined the sequential steps of crushing, puffing and milling of the wheat bran to produce the dietary fiber powder. Method II and method I are the same in the processing steps, but distinct in maintained humidity of the bran, processing speeds and temperature of both extruder screw and grinder. The chemical analyses indicated that the ratio of soluble dietary fiber of the dietary fiber powder made via method I increased significantly compared to the raw wheat bran and the dietary fiber powder made via method II. The results also showed that method I was superior to method II in facilitating the increment of the nutrition content, especially in the content of protein, trace elements and minerals. The processed 120–130 mesh purple wheat bran powder is more delicate and tasty.

Little is known about how metabolic perturbations are linked to hyperuricemia in the general population. Therefore we aimed to examine metabolomics profiles in relation to uric acid change and incident hyperuricemia. This study included 1,621 community‐dwelling Chinese participants ages 50–70 years without hyperuricemia at baseline, with a mean duration of follow‐up of 6 years. A total of 56 metabolites (22 amino acids and 34 acylcarnitines) at baseline were quantified by gas or liquid chromatography coupled to mass spectrometry. Annual change in uric acid was calculated, and incident hyperuricemia was defined as plasma uric acid >420 μmoles/liter in men and >360 μmoles/liter in women. The mean ± SDannual change in uric acid was 9.6 ± 12.1 μmoles/liter and the incidence of hyperuricemia was 23.1% (375 of 1,621). After adjustment for conventional risk factors, 9 metabolites (cysteine, glutamine, phenylalanine, threonine, and long‐chain acylcarnitines C14:1OH, C18, C18:2, C20, and C20:4) were significantly associated with uric acid change (Bonferroni corrected P< 0.05) and with incident hyperuricemia (relative risks ranged from 1.14 to 1.21 per SDincrement of metabolites; P< 0.05). A network analysis showed significant associations between the module containing long‐chain acylcarnitines and incident hyperuricemia. Moreover, levels of these 9 metabolites were specifically correlated with intake of foods, including red and processed meat or soy products. Plasma cysteine, glutamine, phenylalanine, threonine, and long‐chain acylcarnitines are positively associated with incident hyperuricemia. The levels of these metabolites may be partially driven by intakes of meat and soy products that are associated with hyperuricemia.

Sustainable and energy-efficient molecular separation requires membranes with high permeability and selectivity. Among various membranes, the mixed matrix membranes (MMMs) prepared from two-dimensional MXene materials with well-defined nanochannels are expected to be used for the precise separation of molecules. However, the stacking of a large number of 2D MXene nanosheets creates gas mass transfer barriers, resulting in a significant reduction in gas permeability. To solve this issue, herein, a high-performance self-supporting Pebax/CMC@MXene MMM was prepared by a combination of 2D MXene nanosheets with branched carboxymethyl cellulose (CMC) for CO2gas separation from natural gas and flue gas. Gas separation experimental results show that the as-prepared self-supporting Pebax/CMC@MXene MMMs can significantly improve gas permeance and selectivity. When the loading of MXene nanosheets in the CMC@MXene filler was fixed at 1.5 mg/mL, the CO2permeance of Pebax/CMC@MXene MMMs was found to be 521 GPU, and the CO2/N2selectivity was calculated to be 40.1. Meanwhile, the CO2permeance was measured to be 444 GPU, and the CO2/CH4selectivity was calculated to be 40.4. In addition, the resulted as-prepared self-supporting Pebax/CMC@MXene MMM possesses excellent thermal stability and long-term durability; after a 60 h test, its separation performance has no obvious change. The work provides a novel strategy to construct MMMs with less mass transfer barrier for highly efficient capture of CO2from natural gas and flue gas.