The efficient separation of xenon (Xe) and krypton (Kr) is one of the industrially important processes. While adsorptive separation of these two species is considered to be an energy efficient ...process, developing highly selective adsorbent remains challenging. Herein, a rigid squarate-based metal–organic framework (MOF), having a perfect pore size (4.1 Å × 4.3 Å) comparable with the kinetic diameter of Xe (4.047 Å) as well as pore surface decorated with very polar hydroxyl groups, is able to effectively discriminate Xe atoms, affording a record-high Xe/Kr selectivity. An exceptionally high Xe uptake capacity of 58.4 cm3/cm3 and selectivity of 60.6 at low pressure (0.2 bar) are achieved at ambient temperature. The MOF exhibits the highest Xe Henry coefficient (192.1 mmol/g/bar) and Xe/Kr Henry selectivity (54.1) among all state-of-the-art adsorbents reported so far. Direct breakthrough experiments further confirm the excellent separation performance. The density functional theory calculations reveal that the strong interaction between Xe and the framework is a result of the synergy between optimal pore size and polar porosity.
Purification of C2H4 from an C2H4/C2H6 mixture, one of the most important while challenging industrial separation processes, is mainly through energy‐intensive cryogenic distillation. Now a family of ...gallate‐based metal–organic framework (MOF) materials is presented, M‐gallate (M=Ni, Mg, Co), featuring 3D interconnected zigzag channels, the aperture sizes of which (3.47–3.69 Å) are ideally suitable for molecular sieving of ethylene (3.28×4.18×4.84 Å3) and ethane (3.81×4.08×4.82 Å3) through molecular cross‐section size differentiation. Co‐gallate shows an unprecedented IAST selectivity of 52 for C2H4 over C2H6 with a C2H4 uptake of 3.37 mmol g−1 at 298 K and 1 bar, outperforming the state‐of‐the‐art MOF material NOTT‐300. Direct breakthrough experiments with equimolar C2H4/C2H6 mixtures confirmed that M‐gallate is highly selective for ethylene. The adsorption structure and mechanism of ethylene in the M‐gallate was further studied through neutron diffraction experiments.
Purification of C2H4 from an C2H4/C2H6 mixture using a family of gallate‐based metal–organic framework (MOF) materials is presented. M‐gallate (M=Ni, Mg, Co), features 3D interconnected zigzag channels, the aperture sizes of which are ideal for molecular sieving of ethylene and ethane through molecular cross‐section size differentiation.
The demand for CO2/C2H2 separation, especially the removal of CO2 impurity, continues to grow because of the high-purity C2H2 required for various industrial applications. The adsorption separation ...of C2H2 and CO2 via porous materials is gaining a considerable attention as it is more energy-efficient compared with cryogenic distillation. The ideal porous materials are those that preferentially adsorb CO2 over C2H2; however, very few adsorbents meet such requirement. Herein, two isostructural cyclodextrin-based CD-MOFs (CD-MOF-1 and CD-MOF-2) were demonstrated to have an inverse ability to selectively capture CO2 from C2H2 by single-component adsorption isotherms and dynamic breakthrough experiments. These two MOFs showed excellent adsorption capacity and benchmark selectivity (118.7) for CO2/C2H2 mixture at room temperature, enabling the pure C2H2 to be obtained in only one step. This work revealed that these materials were promising adsorbents for obtaining high-purity C2H2 via selectively capturing CO2 from C2H2.
Rapid and efficient detecting trace amount of environmental p-nitroaniline (p-NA) is in urgent need for security concerns and pollution supervision. In this work we report the use of molecularly ...imprinted polymeric ionic liquid (MIPIL) microspheres to construct recognizable surfaces for detection of p-NA through fluorescence quenching. The p-NA imprinted microspheres are synthesized by precipitation polymerization upon co-polymerization of 3-(anthracen-9-ylmethyl)-1-vinyl-1H-imidazol-3-ium chloride (Fluorescent IL monomer) with ethyleneglycol dimethacrylate (EGDMA). The electron-rich group alkenyl imidazole in IL functional monomer can dramatically improve the emission of anthracene fluorophore and the π-π stacking, electronic, and hydrogen bond between p-NA and MIPIL can efficiently enhance the selective recognition force. The as-synthesized MIPIL microspheres present spherical shape, high fluorescence emission intensity and specific recognition, which showed rapid detection rate (1min), stable reusable property (at least 4 time recycles), wonderful selectivity over several structural analogs, wide linear range (10nM to 10M) with a correlation coefficient of 0.992, and excellent sensitivity (LOD, 9nM). As synthesis and surface functionalization of MIPIL microspheres are well established, the methods reported in this work are facile, rapid and efficient for monitoring p-NA in environmental wastewater.
•A novel MIPIL microspheres for fluorescent sensing of p-nitroaniline was described.•Strong emission of anthracene fluorophore coupled ionic liquid monomer was obtained.•The response time needed in p-nitroaniline sensing was only 1min.•The MIPIL microspheres sensor could recognize p-nitroaniline from its analogs.•The p-nitroaniline fluorescent detection results in real water samples are in well accordance with HPLC measurements.
Rainwater utilization is a technical means of comprehensive utilization of rainwater. These include environmentally and economically friendly methods of irrigating farmland and storing water for ...flushing. The construction of “sponge city” is also the key point that the society pays close attention to nowadays. Rainwater utilization and “sponge city” are to solve the problem of urban waterlogging from the concept to the purpose of construction. Based on certain data, this paper analyzes and expounds the current situation of rainwater utilization at home and abroad, the progress of “sponge city” construction and the desirable experience of advanced countries, summarizes its development trend through case analysis, and puts forward the prospect of future rainwater utilization and “sponge city” construction and development.
•The distribution of ARGs and their hosts in pig farm A/O WWTPs is revealed.•Genome bins are used to explore the ARG hosts in pig farm A/O WWTPs.•Dominant denitrifying bacteria are important ARG ...hosts in pig farm A/O WWTPs.
The anoxic-oxic (A/O) wastewater treatment process that is widely used in pig farms in China is an important repository for antibiotic resistance genes (ARGs). However, the distribution of ARGs and their hosts in the A/O process has not been well characterized. In this study, the wastewaters in the anoxic and oxic tanks for A/O processes were collected from 38 pig farms. The concentrations of 20 subtypes of ARGs, 5 denitrification-related genes, 2 integrons, and bacterial community composition were investigated. Bacterial genome binning was performed using metagenome sequencing. In this study, 20 subtypes of ARGs and integrons were detected in all sampling sites. A total of 16 of the 20 subtypes of ARGs were detected with the highest abundance in anoxic tanks, and sul1 was detected with a maximum average abundance of 19.21 ± 0.24 log10 (copies/mL). Cooccurrence patterns were observed for some genes in the pig farm A/O process, such as sul1 and intl1, sul1 and tetG, and tetO and tetW. There was a significant cooccurrence pattern between the dominant denitrifying bacteria and some ARGs (blaTEM, ermB, tetC, tetH and tetQ), so the dominant denitrifying bacteria were considered to be potential ARG hosts. In addition, 170 highly abundant bacterial genome bins were assembled and further confirmed that the denitrifying bacteria Brachymonas, Candidatus Competibacter, Thiobacillus and Steroidobacter were the important ARG hosts in the pig farm A/O process, providing a useful reference for the surveillance and risk management of ARGs in pig farm wastewater.
Loss of melanocytes (MCs) is the most notable feature of vitiligo. Hence, it is critical to clarify the mechanisms of MC destruction in vitiligo. Apoptosis is most widely studied cell death pathways ...in vitiligo. In addition, the other two forms of cell death, conventional necrosis and autophagy seem to be involved in the death of vitiligo MCs under certain situations. Moreover, new types of regulated cell death including necroptosis, pyroptosis, and ferroptosis may also participate in the pathogenesis of vitiligo. Anoikis is likely to be connected with the death of detached MCs, which is provoked specifically by loss of anchorage. Primary phagocytosis, later called phagoptosis can execute death of viable cells, probably partly responsible for the loss of MCs in vitiligo. In this review, we aim to summarize the latest insights into various forms of MC death in vitiligo and discuss the corresponding mechanisms.
The pore size of adsorbents plays a vital role in determining the overall separation performance of gas separation and purification by adsorption. In this work, the pore apertures of the coordination ...pillared layer (CPL) was systematically controlled by adjusting the length of pillared ligands. We used pyrazine, 4,4′-bipyridine, and 1,2-di(4-pyridyl)-ethylene with increased length to synthesize CPL-1 (L = pyrazine), CPL-2 (L = 4,4′-bipyridine), and CPL-5 L = 1,2-di(4-pyridyl)-ethylene, respectively. The aperture size of these CPLs varies from 4 to 11 Å: CPL-1 (4 × 6 Å2), CPL-2 (9 × 6 Å2), and CPL-5 (11 × 6 Å2). Among the three frameworks, CPL-2 exhibits the highest C2H2 uptake at ambient conditions as it has moderate pore size and porosity. However, CPL-1 has the best separation performance in the breakthrough experiments with binary gas mixture of C2H2/C2H4, thanks to the optimal pore size nearly excluding C2H4, which is only observed in the state-of-the-art UTSA-300a so far. The DFT calculations were carried out to elucidate the specific adsorption sites for both acetylene and ethylene among these frameworks. The modeling results suggest that binding strength is highly related to aperture size and that CPL-1 shows the highest adsorption selectivity owing to the optimal pore size. This work demonstrates that engineering pore size enables us to fabricate the highly efficient metal–organic framework (MOF)-based adsorbents for specific gas separation on the basis of the isoreticular chemistry.
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•12 aromatic ketones were obtained by the direct benzylic oxidation.•The oxidation can proceed at room temperature and it takes only 3h.•It employs Co(ClO4)2 as catalyst and oxone as ...oxidant.
Aromatic ketones were synthesized from alkylbenzene derivatives through a novel method that employs cobalt(II) perchlorate as catalyst and oxone as oxidant. The reaction smoothly proceeded at room temperature with yields reaching 96%.
The Suzuki-Miyaura reaction is one of the most popular and efficient routes for the formation of carbon-carbon bonds in both laboratorial and industrial synthetic processes. Here, we report for the ...first time that a Au-Pd/TiO
catalyst could be utilized efficiently for Suzuki-Miyaura reactions at ambient conditions under visible light with high activity and reusability. Mechanistic investigation by means of experimental methods revealed that through the strong local surface plasma resonance of Au under the visible light, the hot electrons of Au could be injected into Pd in the bimetallic nanoparticles, thus facilitating activation of the aryl halides. Meanwhile, the electropositive Au tended to gain electrons from TiO
, resulting in the separation of the photogenerated electron/hole pairs of TiO
, which enabled the holes to activate aryl boronic acids. This Au-Pd/TiO
catalyst not only expands the application scope of Suzuki-Miyaura reactions under mild conditions but will also inspire further exploitation of the direct harvesting of visible light by nanomaterials for a wide range of chemical reactions.
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