The separation of H2/CH4 mixtures is very common in the natural gas and petrochemical industries. There are some higher C2–C4 hydrocarbons and water vapor that are used as impurity gases. Si-CHA zeolite membranes display a high H2 permeance of 1.44 × 10–6 mol/(m2 s Pa) (permeability of 10800 barrers) and H2/CH4 selectivity of 85 for an equimolar H2/CH4 mixture at 298 K and 0.2 MPa pressure drop. A third gas decreased H2 permeance and H2/CH4 selectivity of the membrane. Hydrogen permeance was reduced in an order similar to the adsorption amount in zeolite: H2O > C3H8 > n-butane > ethane. The effects of temperature, pressure, and feed concentration were studied on separation performances of the membrane in the binary and ternary mixtures. A simple model was built up to predict the reduction of permeance and selectivity when multi impurities were contained, and the predicted value agreed well with the tested one. A stable performance was obtained within several hours in all the tests. The separation performance of the membrane was recovered to the original level when the impurity gas was removed.

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Precise molecular and ion separations depend largely on the size and uniformity of the nanochannels in a defect-free microporous nanofilm. Ordered and perpendicular nanochannels with uniform pore size are assembled into a continuous and defect-free film by a "gel nuclei-less" route. The ultrathin (<50 nm) zeolite nanosheets seeding layer induces the formation of defectfree zeolite nanofilms (500-800 nm) with preferential [100] orientation well-aligned to the transport pathway. The large-area and thin silicoaluminophosphate-34 (SAPO-34) nanofilm consisting of uniform and straight nanochannels shows a milestone CO 2 permeance of ≈1.0 × 10 −5 mol (m 2 s Pa) −1 and high CO 2 /CH 4 and CO 2 /N 2 selectivities of 135 and 41 in equimolar binary mixtures at room temperature and 0.2 MPa feed pressure, respectively. These results suggest that highly oriented and thin SAPO-34 nanofilms prepared from nanosheets might have great potential for CO 2 capture from natural gas, biogas, and flue gas.

Cultivated land resources are important natural resource assets that are related to food security and sustainable development. Due to the many restrictive factors of the karst landform on agricultural production, the quantity and quality of cultivated land in the karst mountainous areas in Southwest China are poor. Reclaiming cultivated land to develop economy or to avoid transitional reclamation to protect ecology is an important proposition in this area. Analyzing changes in the physical and monetary value of cropland resources can help us to formulate more reasonable policies for the development and utilization of cultivated land resources, and to achieve a win-win scenario for economic development and ecological protection. Using multi-source remote sensing data and 20-year landcover data obtained by the GEE platform, this paper evaluated the cropland resources of the karst mountain areas of China at the pixel level. It was found that under the apparent outflow of the physical account of the cultivated land resources, the monetary value still maintained growth, proving that the current cultivated land-use policy in Guizhou Province has significantly improved the value of local cultivated land resources.

Forests, serving as crucial custodians of our planet’s ecological balance, also constitute a significant source of livelihood for humanity. Karst regions, recognized as some of the world’s most susceptible landscapes, grapple with the dual predicaments of ecological restoration and resident impoverishment. To bridge the gap between environmental and economic concerns, this manuscript employs an amalgamation of remote sensing and socio-economic methodologies to devise a comprehensive assessment framework, thereby scrutinizing the alterations in forest ecosystems from 2001 to 2020.The investigation reveals that over the past two decades, forest rehabilitation within the study area has yielded commendable outcomes, substantially mitigating various ecological dilemmas instigated by rocky desertification in this region. The forested area has increased significantly, and the ecosystem service value has more than doubled. These improvements are largely attributed to compulsory forest conservation measures, demonstrating their decisive influence. The study advocates meticulous management and conservation strategies to safeguard these unique ecosystems and ensure their sustainability. This research underscores the significance of striking a balance between maintaining ecological integrity and fostering economic development, thereby contributing to the broader discourse on sustainable forest management in vulnerable landscapes.