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Utilizing Mars Atmosphere and Volatile EvolutioN (MAVEN) observations from October 2014 to May 2023, we perform a detailed survey of magnetosonic waves generated in the solar wind (refer to as upstream MS waves), with frequencies near the proton gyrofrequency in the solar wind environment. The distribution of the solar wind‐generated MS waves has been carefully investigated, including in the solar wind and in the Martian magnetosphere by propagation. The results show that these MS waves are widely distributed below the Martian bow shock but are more concentrated below the magnetic pileup boundary, particularly in the subsolar region. The waves possess higher occurrence rates on the dayside with larger amplitudes; the occurrence rates also show dusk‐side‐preferred asymmetry. The Martian crustal magnetic field can prevent MS waves from penetrating into lower altitudes, while higher solar dynamic pressure benefits their penetration. The wave amplitudes exhibit a weak positive correlation with the solar wind dynamic pressure. These obtained global distribution features of Martian upstream MS waves observed by MAVEN are valuable to improve current understanding of the dynamic variations of Martian charged particles and the underlying contribution of wave‐particle interactions driven by MS waves. Plain Language Summary: Magnetosonic waves with frequencies near the proton gyrofrequency in the solar wind environment play an important role in altering the plasma and atmospheric environment of the planet through interactions with charged particles. In this study, we statistically investigate, using Mars Atmosphere and Volatile EvolutioN observations from October 2014 to May 2023, how these waves, referred to as upstream MS waves, are distributed in the Martian space. They are found to occupy the space downstream of the bow shock but are more concentrated below the magnetic pileup boundary. Also, they are seen more frequently on the dayside and dusk side than on the other halves. The penetration of upstream MS waves becomes difficult when encountering the Martian crustal field, or when the solar dynamic pressure is lower than usual. The amplitude of waves tends to grow larger when the solar dynamic pressure increases. These results can greatly benefit studies on how charged particles can be accelerated by the waves and escape from Mars, which could profoundly change the climate of this planet. Key Points: Upstream MS waves are predominantly below the dayside magnetic pileup boundary of Mars with a dawn‐dusk asymmetry in distributionUpstream MS waves can more easily propagate to lower altitudes in the dayside regions with weak crustal magnetic field of MarsSolar wind dynamic pressure can influence the occurrence of upstream MS waves [ABSTRACT FROM AUTHOR]

This systematic review and meta-analysis aimed to assess and compare the therapeutic outcomes of cutting balloon angioplasty and high-pressure balloon angioplasty for arteriovenous fistula stenosis in hemodialysis patients. All studies indexed in PubMed, Embase, and Cochrane Library Web of Science were retrieved. The retrieval deadline was July 15, 2023. Risk of bias 2.0 was used to evaluate the quality of the included studies. Revman 5.4 software was used for data analysis. This review included three studies and 180 patients, with 90 patients in the cutting balloon angioplasty group and 90 patients in the high-pressure balloon angioplasty group. The results of the meta-analysis suggested that compared with high-pressure balloon angioplasty, cutting balloon angioplasty can improve primary lesion patency rates of internal arteriovenous fistulas at 6 months (relative risk, 1.45; 95% confidence interval, 1.08–1.96; P = 0.01). However, there were no significant differences between the technical success rate (relative risk, 0.99; 95% confidence interval, 0.93–1.05; P = 0.72) and clinical success rate (relative risk, 1.01; 95% confidence interval, 0.95–1.07; P = 0.73). Therefore, cutting balloon angioplasty is likely to increase primary lesion patency rates at 6 months. However, more high-quality, large-sample, multicenter, randomized controlled trials are needed for further validation due to the limited number of included studies. [ABSTRACT FROM AUTHOR]

Membrane separation is an energy‐efficient and environmentally friendly process. Two‐dimensional (2D) molecular sieving membranes featuring unique nanopores and low transport resistance have the potential to achieve highly permeable and selective mixture separation with low energy consumption. High‐aspect‐ratio zeolite nanosheets with intrinsic molecular‐sieving pores perpendicular to the layers are desirable building blocks for fabricating high‐performance 2D zeolite membrane. However, a wider application of 2D zeolitic membranes is restricted by the limited number of recognized zeolite nanosheets. Herein, we report a swollen layered zeolite, ECNU‐28, with SZR topology and eight‐member ring (8‐MR, 3.0 Å×4.8 Å) pores normal to the nanosheets. It can be easily exfoliated to construct 2D membrane, which shows a high hydrogen selectivity up to 130 from natural gas and is promising for hydrogen purification and greenhouse gas capture. [ABSTRACT FROM AUTHOR]

The kinetic models were widely used to analyze the dynamic adsorption behaviors in a batch system and reveal the mass-transfer mechanisms. The previous review papers were mainly confined to the description of the kinetic models, assessment of the fitting quality, determination of the model parameters and practical application in the field of water and wastewater treatment. However, the curve characteristics of the kinetic models and their mathematical relations were rarely mentioned in the literature. How to select and determine the optimum model remained to be further discussed. Thus, in addition to improving previous work, the main objectives of this review were: (i) to identify the curve characteristics of the kinetic models by control variates; (ii) to reveal their mathematical relations by variable substitution; (iii) to determine the optimum model by error functions and residual plot; and (iv) to correct some common mistakes in the literature. The pseudo-first-order (PFO) and pseudo-second-order (PSO) equations were two special cases of mixed 1,2-order equation (MOE). The PFO and Furusawa–Smith equations were mathematically equivalent. This review is expected to help readers better understand and use the adsorption kinetic models and provide potential ideas for the development of new kinetic models. [ABSTRACT FROM AUTHOR]

Metal–organic framework membranes are usually prepared by in situ or secondary growth in a solution/hydrogel. The use of organic solvents may cause safety and environmental problems and produce solvent‐induced defects. Here, highly oriented and permselective ZIF‐95 membranes are prepared for the first time via a solvent‐free secondary growth method. The solvent‐free growth is not only helpful to control the membrane microstructure and thickness, but also to reduce the intercrystalline defects. In case of solvent‐free growth, a perfectly oriented structure leads to an outstanding reduction of intercrystalline defects and transport resistances. For the separation of equimolar binary gas mixtures by using the highly oriented ZIF‐95 membrane at 25 °C and 1 bar, the mixture separation factors of H2/CO2 and H2/CH4 are 184 and 140, respectively, with H2 permeance of over 1.9×10−7 mol m−2 s−1 Pa−1 which are much higher than those of the randomly oriented ZIF‐95 membrane. [ABSTRACT FROM AUTHOR]

The fabrication of mixed matrix membranes (MMMs) by intermixing suitable fillers with organic polymers is an effective strategy to surmount the well-known trade-off effect between gas permeability and selectivity, which can promote separation performance of membranes to a great extent. Two-dimensional (2D) metal-organic frameworks (MOFs) are considered as potential fillers for strengthening the separation performance of MMMs as they possess high aspect ratio and distinctive chemical characteristics. However, it remains challenging in engineering the morphology of the MOFs with desired pore structure and high aspect ratio. In this study, we firstly prepare c-axis oriented ZIF-95 sheets with lateral dimension exceeding 22 μm and thickness of around 3 μm by the solvothermal method. And then the ZIF-95 sheets are incorporated into the polyimide (PI) matrix to fabricate highly c -axis oriented ZIF-95@PI MMMs (denoted as COZIF-95@PI MMMs thereafter). Attributing to the straight permeation channel of ZIF-95 (3.6 Å) for gas permeation as well as its high compatibility with polyimide substrates, the COZIF-95@PI MMMs show a high gas separation capability. At 373 K and 100 kPa for the COZIF-95@PI MMM with 40 wt% loading, the mixture separation factors of H 2 /CH 4 and H 2 /CO 2 are 134 and 58, respectively, and the H 2 permeability exceeds 967 barrer , which is hopeful for the separation and purification of hydrogen. [Display omitted] • ZIF-95 sheets with well-shaped morphology and high aspect ratio are successfully synthesized. • The ZIF-95 sheets are used as fillers for fabrication of highly c -axis oriented mixed matrix membranes. • The straight permeation channel of ZIF-95 along c -axis orientation is dominant for gas permeation. • The developed ZIF-95 mixed matrix membranes display high hydrogen permselectivity. [ABSTRACT FROM AUTHOR]