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Air pollution by SO2 and NO2 has caused significant risks on the environment and human health. Understanding the mechanism of active sites within capture materials is of fundamental importance to the development of new clean-up technologies. Here we report the crystallographic observation of reversible coordinative binding of SO2 and NO2 on open NiII sites in a metal-organic framework (NKU-100) incorporating unprecedented {Ni12 }-wheels; each wheel exhibits six open NiII sites on desolvation. Immobilised gas molecules are further stabilised by cooperative host-guest interactions comprised of hydrogen bonds, π⋅⋅⋅π interactions and dipole interactions. At 298 K and 1.0 bar, NKU-100 shows adsorption uptakes of 6.21 and 5.80 mmol g-1 for SO2 and NO2 , respectively. Dynamic breakthrough experiments have confirmed the selective retention of SO2 and NO2 at low concentrations under dry conditions. This work will inspire the future design of efficient sorbents for the capture of SO2 and NO2 .

We report the high NH3 uptake in a series of copper-carboxylate materials, namely MFM-100, MFM-101, MFM-102, MFM-126, MFM-127, MFM-190(F), MFM-170, and Cu-MOP-1a. At 273 K and 1 bar, MFM-101 shows an exceptional uptake of 21.9 mmol g−1. The presence of Cu(II)⋯NH3 interactions and changes in coordination at the [Cu2(O2CR)4] paddlewheel are analysed and discussed. [ABSTRACT FROM AUTHOR]

Metagenomic analyses facilitate the exploration of the microbial world, advancing our understanding of microbial roles in ecological and biological processes. A pivotal aspect of metagenomic analysis involves assessing the quality of metagenome-assembled genomes (MAGs), crucial for accurate biological insights. Current machine learning–based methods often treat completeness and contamination prediction as separate tasks, overlooking their inherent relationship and limiting models' generalization. In this study, we present DeepCheck, a multitasking deep learning framework for simultaneous prediction of MAG completeness and contamination. DeepCheck consistently outperforms existing tools in accuracy across various experimental settings and demonstrates comparable speed while maintaining high predictive accuracy even for new lineages. Additionally, we employ interpretable machine learning techniques to identify specific genes and pathways that drive the model's predictions, enabling independent investigation and assessment of these biological elements for deeper insights. [ABSTRACT FROM AUTHOR]

This work reports the thermal and electron beam stabilities of a series of isostructural metal–organic frameworks (MOFs) of type MFM-300(M) (M = Al, Ga, In, Cr). MFM-300(Cr) was most stable under the electron beam, having an unusually high critical electron fluence of 1111 e− Å−2 while the Group 13 element MOFs were found to be less stable. Within Group 13, MFM-300(Al) had the highest critical electron fluence of 330 e− Å−2, compared to 189 e− Å−2 and 147 e− Å−2 for the Ga and In MOFs, respectively. For all four MOFs, electron beam-induced structural degradation was independent of crystal size and was highly anisotropic, although both the length and width of the channels decreased during electron beam irradiation. Notably, MFM-300(Cr) was found to retain crystallinity while shrinking up to 10%. Thermal stability was studied using in situ synchrotron X-ray diffraction at elevated temperature, which revealed critical temperatures for crystal degradation to be 605, 570, 490 and 480 °C for Al, Cr, Ga, and In, respectively. The pore channel diameters contracted by ≈0.5% on desorption of solvent species, but thermal degradation at higher temperatures was isotropic. The observed electron stabilities were found to scale with the relative inertness of the cations and correlate well to the measured lifetime of the materials when used as photocatalysts. [ABSTRACT FROM AUTHOR]

Stimuli‐responsive physisorbents that undergo reversible structural transformations induced by external stimuli (e.g. light, guests, or heat) offer the promise of utility in gas storage and separation. Whereas reports on guest or light‐responsive sorbents have increased in recent years, we are unaware of reports on sorbents that exhibit both light and guest‐induced structural transformations. Herein, we report that the square lattice, sql, topology coordination network Zn(fba)(bis) ⋅ 2DMF (sql‐5,6‐Zn‐α, 5=trans‐4,4′‐bis(1‐imidazolyl)stilbene=bis, 6=2,2‐bis(4‐carboxyphenyl)hexafluoropropane=H2fba) underwent single‐crystal‐to‐single‐crystal transformation (SCSC) upon activation, affording nonporous sql‐5,6‐Zn‐β. Parallel alignment at 3.23 Å of olefinic moieties on adjacent bis ligands in sql‐5,6‐Zn‐α enabled SCSC [2+2] photocycloaddition upon exposure to UV light (365 nm) or sunlight. sql‐5,6‐Zn‐α thereby transformed to mot‐5,6‐Zn‐α, which was subsequently activated to the narrow pore phase mot‐5,6‐Zn‐β. sql‐5,6‐Zn‐β and mot‐5,6‐Zn‐β both exhibited S‐shaped adsorption isotherms characteristic of guest‐induced structural changes when exposed to CO2 at 195 K (type‐F–IV and type F–I, respectively). Cycling experiments conducted upon sql‐5,6‐Zn‐β reduced particle size after cycle 1 and induced transformation into a rare example of a shape memory coordination network, sql‐5,6‐Zn‐γ. Insight into this smorgasbord of SCSC phase changes was gained from in situ PXRD, single crystal XRD and 1H NMR spectroscopy experiments. [ABSTRACT FROM AUTHOR]

Human activities and natural resource changes have exerted considerable impact on the ecosystem service value (ESV) of Zhengzhou City. In this study, the standard equivalent factor, which was revised according to the basic land-use data of 1990, 2000, 2010 and 2020, was adopted combined with the patch-generation land-use change simulation (PLUS) model to simulate the land-use data of Zhengzhou in three scenarios (nature development, cultivated land protection and ecological protection) in the year 2030. In this way, the spatio-temporal evolution of ecosystem service value was analyzed and forecast. Results of the modeling simuation showed that main land-use pattern of Zhengzhou was cultivated land and construction land in 1990-2020, and the dynamic degree of construction land-use area reached the apex (9.85%) from 2000 to 2010; During the period between 1990 and 2020, the area of low ESV in Zhengzhou was distributed in a "lamellar " form, accounting for 65.19% in 2020, and during the time the increased area being up to 1 339.58 km², the areas of median and slightly high ESV were distributed in the form of "secondary nuclear and tertiary", and the area of high ESV accounted for 3.59%; ESV of Zhengzhou decrease by 1.391 9 billion yuan during this period, the gain of ESV mainly came from the conversion of cultivated land to water bodies, while the loss od ESV was caused by the conversion of forest land to construction land, forest land to farmland and waterbodies to construction land. With respect to the above three scenarios, in the ecological protection scenario the variation amplitude of land use area was the smallest; ESV decreased in the natural development and cultivated land protection scenarios; and ESV increased by 123 million yuan in ecological protection scenario, with the "cold point" concentration being more obvious. It is expected that the results of this study would provide positive guidance for the territorial planning and ecological protection of Zhengzhou. [ABSTRACT FROM AUTHOR]

Objective: To screen ferroptosis genes related to prognosis of malignant pleural mesothelioma (MPM), explore the relationship between ferroptosis and tumor immune microenvironment and provide a new perspective for targeting and immunotherapy of MPM patients. Methods: The differentially expressed genes (DEGs) in MPM tumor group and normal group were analyzed in GEO database; intersection of DEGs and ferroptosis genes to obtain differentially expressed ferroptosis-related genes (DE-FRGs). GO, KEGG function enrichment and protein protein interaction (PPI) were used to identify the signal pathways mainly involved by DEFRGs. The prognosis related ferroptosis genes were identified by univariate COX analysis. LASSO regression analysis was used to screen the best DE-FRGs for establishing the risk prediction model, and a risk prognosis model based on the best DE-FRGs was established by multivariate cox analysis to verify the prediction effect of the model. Finally, CIBERSORT and other algorithms were used to analyze tumor immune cell infiltration and evaluate immune microenvironment. Results: Twenty-four prognosis related DE-FRGs were screened, which were mainly concentrated in ferroptosis, transcriptional regulation and response to inorganic substances. A MPM risk prediction model based on five ferroptosis-related genes (ALDH3A2, CAV1, HRAS, CDCA3 and RRM2) was established and validated. In the model, the proportion of CD8+T cells and macrophages in high-risk group were higher, while the proportion of B lymphocytes was lower. In addition, PD-1, CTLA-4 and their ligands at immune checkpoint had higher expression status in high-risk group. Conclusion: The MPM risk prediction model based on five ferroptosis-related genes is established, and the immune status in the model is clarified. It provides a certain research basis for targeting and immunotherapy of MPM. The predictive ability of this model in MPM needs to be further verified in clinical practice to better predict disease stratification and treatment management. [ABSTRACT FROM AUTHOR]

The selective capture of methane (CH4) at low concentrations and its separation from N2 are extremely challenging owing to the weak host‐guest interactions between CH4 molecules and any sorbent material. Here, we report the exceptional adsorption of CH4 at low pressure and the efficient separation of CH4/N2 by MFM‐300(Fe). MFM‐300(Fe) shows a very high uptake for CH4 of 0.85 mmol g−1 at 1 mbar and 298 K and a record CH4/N2 selectivity of 45 for porous solids, representing a new benchmark for CH4 capture and CH4/N2 separation. The excellent separation of CH4/N2 by MFM‐300(Fe) has been confirmed by dynamic breakthrough experiments. In situ neutron powder diffraction, and solid‐state nuclear magnetic resonance and diffuse reflectance infrared Fourier transform spectroscopies, coupled with modelling, reveal a unique and strong binding of CH4 molecules involving Fe−OH⋯CH4 and C⋯phenyl ring interactions within the pores of MFM‐300(Fe), thus promoting the exceptional adsorption of CH4 at low pressure. [ABSTRACT FROM AUTHOR]

Heterojunctions combining two photocatalysts of staggered conduction and valence band energy levels can increase the photocatalytic efficiency compared to their individual components. This activity enhancement is due to the minimization of undesirable charge recombination by the occurrence of carrier migration through the heterojunction interface with separated electrons and holes on the reducing and oxidizing junction component, respectively. Metal–organic frameworks (MOFs) are currently among the most researched photocatalysts due to their tunable light absorption, facile charge separation, large surface area and porosity. The present review summarizes the current state-of-the-art in MOF-based heterojunctions, providing critical comments on the construction of these heterostructures. Besides including examples showing the better performance of MOF heterojunctions for three important photocatalytic processes, such as hydrogen evolution reaction, CO2 photoreduction and dye decolorization, the focus of this review is on describing synthetic procedures to form heterojunctions with MOFs and on discussing the experimental techniques that provide evidence for the operation of charge migration between the MOF and the other component. Special attention has been paid to the design of rational MOF heterojunctions with small particle size and controlled morphology for an appropriate interfacial contact. The final section summarizes the achievements of the field and provides our views on future developments. [ABSTRACT FROM AUTHOR]

Formamides are important feedstocks for the manufacture of many fine chemicals. State‐of‐the‐art synthesis of formamides relies on the use of an excess amount of reagents, giving copious waste and thus poor atom‐economy. Here, we report the first example of direct synthesis of N‐formamides by coupling two challenging reactions, namely reductive amination of carbonyl compounds, particularly biomass‐derived aldehydes and ketones, and fixation of CO2 in the presence of H2 over a metal‐organic framework supported ruthenium catalyst, Ru/MFM‐300(Cr). Highly selective production of N‐formamides has been observed for a wide range of carbonyl compounds. Synchrotron X‐ray powder diffraction reveals the presence of strong host‐guest binding interactions via hydrogen bonding and parallel‐displaced π⋅⋅⋅π interactions between the catalyst and adsorbed substrates facilitating the activation of substrates and promoting selectivity to formamides. The use of multifunctional porous catalysts to integrate CO2 utilisation in the synthesis of formamide products will have a significant impact in the sustainable synthesis of feedstock chemicals. [ABSTRACT FROM AUTHOR]

MFM‐520(Zn) confines dimers of NO2 with a high adsorption of 4.52 mmol g−1 at 1 bar at 298 K. The synthesis and the incommensurate structure of Cu‐doped MFM‐520(Zn) are reported. The introduction of paramagnetic Cu2+ sites allows investigation of the electronic and geometric structure of metal site by in situ electron paramagnetic resonance (EPR) spectroscopy upon adsorption of NO2. By combining continuous wave and electron‐nuclear double resonance spectroscopy, an unusual reverse Berry distorted coordination geometry of the Cu2+ centers is observed. Interestingly, Cu‐doped MFM‐520(Zn0.95Cu0.05) shows enhanced adsorption of NO2 of 5.02 mmol g−1 at 1 bar at 298 K. Whereas MFM‐520(Zn) confines adsorbed NO2 as N2O4, the presence of monomeric NO2 at low temperature suggests that doping with Cu2+ centers into the framework plays an important role in tuning the dimerization of NO2 molecules in the pore via the formation of specific host‐guest interactions. [ABSTRACT FROM AUTHOR]