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There are great challenges in developing efficient adsorbents to replace the currently used and energy-intensive cryogenic distillation processes for olefin/paraffin separation, owing to the similar physical properties of the two molecules. Here we report an ultramicroporous metal–organic framework [Ca(C4O4)(H2O)], synthesized from calcium nitrate and squaric acid, that possesses rigid one-dimensional channels. These apertures are of a similar size to ethylene molecules, but owing to the size, shape and rigidity of the pores, act as molecular sieves to prevent the transport of ethane. The efficiency of this molecular sieve for the separation of ethylene/ethane mixtures is validated by breakthrough experiments with high ethylene productivity under ambient conditions. This material can be easily synthesized at the kilogram scale using an environmentally friendly method and is water-stable, which is important for potential industrial implementation. The strategy of using highly rigid metal–organic frameworks with well defined and rigid pores could also be extended to other porous materials for chemical separation processes.

Separation of C 2 H 4 from C 2 H 4 /C 2 H 2 /C 2 H 6 mixture with high working capacity is still a challenging task. Herein, we deliberately design a Th-metal-organic framework (MOF) for highly efficient separation of C 2 H 4 from a binary C 2 H 6 /C 2 H 4 and ternary C 2 H 4 /C 2 H 2 /C 2 H 6 mixture. The synthesized MOF Azole-Th-1 shows a UiO-66-type structure with fcu topology built on a Th 6 secondary building unit and a tetrazole-based linker. Such noticeable structure, is connected by a N,O-donor ligand with high chemical stability. At 100 kPa and 298 K Azole-Th-1 performs excellent separation of C 2 H 4 (purity > 99.9%) from not only a binary C 2 H 6 /C 2 H 4 (1:9, v/v) mixture but also a ternary mixture of C 2 H 6 /C 2 H 2 /C 2 H 4 (9:1:90, v/v/v), and the corresponding working capacity can reach up to 1.13 and 1.34 mmol g −1 , respectively. The separation mechanism, as unveiled by the density functional theory calculation, is due to a stronger van der Waals interaction between ethane and the MOF skeleton. Separation of ethylene from C2 ternary mixture with high working capacity is a challenging task. Here, the authors report a Th-azole framework (Azole-Th-1) for highly efficient purification of ethylene from C 2 H 4 /C 2 H 6 and C 2 H 4 /C 2 H 2 /C 2 H 6 mixtures, respectively.

Molecular sieving membranes with sufficient and uniform nanochannels that break the permeability-selectivity trade-off are desirable for energy-efficient gas separation, and the arising two-dimensional (2D) materials provide new routes for membrane development. However, for 2D lamellar membranes, disordered interlayer nanochannels for mass transport are usually formed between randomly stacked neighboring nanosheets, which is obstructive for highly efficient separation. Therefore, manufacturing lamellar membranes with highly ordered nanochannel structures for fast and precise molecular sieving is still challenging. Here, we report on lamellar stacked MXene membranes with aligned and regular subnanometer channels, taking advantage of the abundant surface-terminating groups on the MXene nanosheets, which exhibit excellent gas separation performance with H 2 permeability >2200 Barrer and H 2 /CO 2 selectivity >160, superior to the state-of-the-art membranes. The results of molecular dynamics simulations quantitatively support the experiments, confirming the subnanometer interlayer spacing between the neighboring MXene nanosheets as molecular sieving channels for gas separation. Two-dimensional materials show great potential for membrane technologies, but their disordered channels hinder their molecular sieving performance. Here, Wang, Gogotsi and colleagues design a MXene membrane with ordered nanochannels that exhibits an excellent H 2 /CO 2 gas separation performance.

Porous materials are very promising for the development of cost- and energy-efficient separation processes, such as for the purification of ethylene from ethylene/ethane mixture—an important but currently challenging industrial process. Here we report a microporous hydrogen-bonded organic framework that takes up ethylene with very good selectivity over ethane through a gating mechanism. The material consists of tetracyano-bicarbazole building blocks held together through intermolecular CN···H–C hydrogen bonding interactions, and forms as a threefold-interpenetrated framework with pores of suitable size for the selective capture of ethylene. The hydrogen-bonded organic framework exhibits a gating mechanism in which the threshold pressure required for guest uptake varies with the temperature. Ethylene/ethane separation is validated by breakthrough experiments with high purity of ethylene (99.1%) at 333 K. Hydrogen-bonded organic frameworks are usually not robust, yet this material was stable under harsh conditions, including exposure to strong acidity, basicity and a variety of highly polar solvents.Porous materials are promising candidates for the cost- and energy-efficient separation of ethylene and ethane from gas mixtures: an important but challenging industrial process. Now, a hydrogen-bonded organic framework has been reported that is stable under harsh conditions and can take up ethylene at practical temperatures—with very high selectivity over ethane—through a gating mechanism.

Two-dimensional (2D) metal-organic framework (MOF) nanosheet membranes hold promise for exact molecular transfer due to their structural diversity and well-defined in-plane nanochannels. However, achieving precise regulation of stacking modes between neighboring nanosheets in membrane applications and understanding its influence on separation performance remains unrevealed and challenging. Here, we propose a strategy for accurately controlling the stacking modes of MOF nanosheets via linker polarity regulation. Both theoretical calculations and experimental results demonstrate that a high linker polarity promotes neighboring nanosheets to a maximum AB stacking due to steric hindrance effects, leading to a controlled effective pore size of the membrane and consequently to improved molecular sieving. Among series of CuBDC-based 2D MOFs with different linkers, the CuBDC-NO 2 nanosheet membranes exhibit a reduced effective stacking aperture of 0.372 nm, yielding H 2 permeance of 4.44 × 10 −7  mol m −2 s −1 Pa −1 with a high H 2 /CO 2 and H 2 /CH 4 selectivity of 266 and 536, respectively. This work represents the in-depth investigation of the accurate tuning of MOF nanosheet stacking in the field of 2D materials, offering more perspectives for broader applications with universality for various 2D materials. The authors propose a strategy to adjust the stacking modes of MOF nanosheets via linker polarity differences. Simulations and experiments reveal that higher linker polarity favors AB stacking, optimizing membrane aperture and enhancing gas sieving.

Sonodynamic therapy (SDT), which is based on photodynamic therapy (PDT), is a new cancer treatment modality. Unlike PDT, which has poor tissue penetration, ultrasound can penetrate deeply into tissues and largely target tumor tissue to mediate the cytotoxicity of sonosensitizers. We hypothesize that, similar to PDT, SDT may perform effectively as a cancer vaccine. Thus, we developed a therapeutic strategy to explore whether SDT can eliminate primary tumors, inhibit metastases, and prevent tumor relapse. In the present study, we found that HiPorfin (HPD)‐induced SDT killed tumor cells, promoted calreticulin expression on the cell surface and elicited immune responses. Meanwhile, we observed that SDT induced functional antitumor vaccination and abscopal effects in H22 tumor‐bearing mice. Furthermore, this strategy conferred an immunological memory, which could protect against tumor recurrence after the elimination of the initial tumor. These results showed important effects of SDT on immune responses. HiPorfin (HPD)‐induced SDT killed tumor cells, promoted calreticulin expression on the cell surface and provoked immune responses. Meanwhile, we observed functional antitumor vaccination and the abscopal effect as a result of SDT in H22 tumor‐bearing mice. Furthermore, this strategy conferred an immunological memory, which could protect against tumor recurrence after elimination of the initial tumor.

During the pandemic, the amount of infectious medical waste has increased dramatically. Currently, the medical waste recycling process generally suffers from defects such as long distances, high costs, and a lack of emergency response mechanisms. This paper addresses the problem of medical waste collection and route optimization for regions with multiple vehicle types and stages. It comprehensively considers factors such as transportation costs, distance, vehicle allocation, and contamination risks during the collection and distribution of medical waste. The goal is to minimize transportation costs and risks, with constraints including uniqueness, connectivity between nodes, and vehicle load capacity. A segmented collection approach is used to model the medical waste collection process. An optimization method for medical waste collection site selection and vehicle routing is proposed. Given the NP-hard nature of the problem, a location allocation method based on minimum envelope clustering analysis is employed, and an improved NSGA-II algorithm incorporating a fast non-dominated sorting mechanism is designed to obtain Pareto optimal solutions. Comparing with the results of traditional genetic algorithms through simulation, the results show that using the improved NSGA-II to solve practical problems: 1. When the production of medical waste is flat (1 disposal center, 4 backup transfer points, 58 producing points), the total cost is reduced by 13.94%, the total mileage is reduced by 7.17%, the full load rate is increased by 6.14%, and the convergence time is 26 seconds. 2. When the production of medical waste increased significantly (1 disposal center, multiple backup transfer points, 58 producing points), the total cost, total mileage, and transportation risk were reduced by 9.50%, 10.35%, and 2.03%, respectively, and the full load rate increased by 5.98%. The final results also indicate that compared to the results obtained by traditional genetic algorithms, the improved NSGA-II algorithm performs better in solving the optimization problem of infectious medical waste transportation routes.

Quantitative understanding of ion transport mechanism is crucial for numerous applications of two-dimensional (2D) nanochannels, but is far from being resolved. Here, we formulated a theoretical framework for both self-diffusion and electromigration of hydrated monatomic ions in various 2D nanochannels (e.g. graphene, h-BN, g-C 3 N 4 , MoS 2 ), by molecular dynamics simulations. The self-diffusivity and mobility of ions in 2D nanochannels both increases linearly with ion-wall distance for small hydrated ions, yet keeps constant for large ones. The underlying mechanism reveals that when ions approach water-layers in nanochannels or possess large hydration shell, their hydration shells become severely distorted. This increases the free energy difference between hydration shell and the surrounding water-layers, water residence time in hydration shell and ion-water friction. Several involving quantitative relations were revealed, with Nernst–Einstein relation validated with both simulations and theoretical derivation. This work shows profound implications for various applications, including ion-sieving, nanodevices and nano-power generators, etc. Ion transport mechanism is crucial for various applications of two-dimensional nanochannels. Here, the authors show quantitatively, how ion-water friction regulates diffusion and electromigration of ions in nanochannels.

Intracerebral hemorrhage (ICH) is the most morbid of all stroke types with a high mortality and significant disability burden. Inhibiting ferroptosis after ICH will effectively treat ICH and improve prognosis. Esculetin is the main active ingredient of the Chinese medicine Cortex Fraxini, which has neuroprotective effects. 7-methylguanosine (m7G) methylation is a common RNA modification that regulates mRNA stability and translation, playing an important role in neural development and function, as well as in ferroptosis-related pathways. In this study, we used hemin-induced PC12 cells to investigate the impact of esculetin on ferroptosis and the involvement of m7G modification. Cell viability was measured by cell counting kit-8. Cell death was evaluated by measuring the levels of LDH release and PI-positive cells. Ferroptosis was assessed by measuring the levels of Fe 2+ , glutathione, lipid reactive oxygen species, and malondialdehyde. The underlying mechanism was investigated by quantitative real-time PCR, methylated RNA immunoprecipitation (MeRIP), and RIP. Results suggested that esculetin promoted cell viability, inhibited ferroptosis, and increased NUDT1-mediated m7G levels in hemin-induced PC12 cells. Besides, NUDT1 interacted with GPX4 and enhanced the mRNA stability of GPX4. Silencing of GPX4 abolished the inhibitory influences of NUDT1 overexpressing on ferroptosis in hemin-induced PC12 cells. The ICH mouse model revealed that esculetin treatment effectively reduced neurological deficits and inhibited ferroptosis. In conclusion, esculetin treatment inhibits ICH-induced ferroptosis by promoting NUDT1-mediated m7G methylation modification and enhancing GPX4 stability. This study contributes to understanding the mechanisms by which esculetin may mitigate ICH damage and may provide a new potential therapeutic target for ICH.

The flue gas from fossil fuel power plants is a long-term stable and concentrated emission source of CO2, and it is imperative to reduce its emission. Adsorbents have played a pivotal role in reducing CO2 emissions in recent years, but the presence of water vapor in flue gas poses a challenge to the stability of adsorbents. In this study, ZIF-94, one of the ZIF adsorbents, showed good CO2 uptake (53.30 cm3/g), and the calculated CO2/N2 (15:85, v/v) selectivity was 54.12 at 298 K. Because of its excellent structural and performance stability under humid conditions, the CO2/N2 mixture was still well-separated on ZIF-94 with a separation time of 30.4 min when the relative humidity was as high as 99.2%, which was similar to the separation time of the dry gas experiments (33.2 min). These results pointed to the enormous potential applications of ZIF-94 for CO2/N2 separation under high humidity conditions in industrial settings.