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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.

The separation of C 2 H 2 /CO 2 is not only industrially important for acetylene purification but also scientifically challenging owing to their high similarities in physical properties and molecular sizes. Ultramicroporous metal-organic frameworks (MOFs) can exhibit a pore confinement effect to differentiate gas molecules of similar size. Herein, we report the fine-tuning of pore sizes in sub-nanometer scale on a series of isoreticular MOFs that can realize highly efficient C 2 H 2 /CO 2 separation. The subtle structural differences lead to remarkable adsorption performances enhancement. Among four MOF analogs, by integrating appropriate pore size and specific binding sites, [Cu(dps) 2 (SiF 6 )] (SIFSIX-dps-Cu, SIFSIX = SiF 6 2- , dps = 4.4’-dipyridylsulfide, also termed as NCU-100) exhibits the highest C 2 H 2 uptake capacity and C 2 H 2 /CO 2 selectivity. At room temperature, the pore space of SIFSIX-dps-Cu significantly inhibits CO 2 molecules but takes up a large amount of C 2 H 2 (4.57 mmol g −1 ), resulting in a high IAST selectivity of 1787 for C 2 H 2 /CO 2 separation. The multiple host-guest interactions for C 2 H 2 in both inter- and intralayer cavities are further revealed by dispersion-corrected density functional theory and grand canonical Monte Carlo simulations. Dynamic breakthrough experiments show a clean C 2 H 2 /CO 2 separation with a high C 2 H 2 working capacity of 2.48 mmol g −1 . The separation of acetylene and carbon dioxide by porous materials requires delicate control over the pore size. Herein, the authors fine-tune the pore size at sub-nanometer scale in a series of isoreticular metal-organic frameworks to control the acetylene/carbon dioxide separation performance; subtle structural differences lead to remarkable performance enhancement.

Industrial production of ethylene requires its separation from ethane in a cryogenic process that consumes large amounts of energy. An alternative would be differential sorption in microporous materials. Most of these materials bind ethylene more strongly that ethane, but adsorption of ethane would be more efficient. Li et al. found that a metal-organic framework containing iron-peroxo sites bound ethane more strongly than ethylene and could be used to separate the gases at ambient conditions. Science , this issue p. 443 A metal-organic framework bearing iron-peroxo sites preferentially adsorbs ethane over ethylene for gas separations. The separation of ethane from its corresponding ethylene is an important, challenging, and energy-intensive process in the chemical industry. Here we report a microporous metal-organic framework, iron(III) peroxide 2,5-dioxido-1,4-benzenedicarboxylate [Fe 2 (O 2 )(dobdc) (dobdc 4− : 2,5-dioxido-1,4-benzenedicarboxylate)], with iron (Fe)–peroxo sites for the preferential binding of ethane over ethylene and thus highly selective separation of C 2 H 6 /C 2 H 4 . Neutron powder diffraction studies and theoretical calculations demonstrate the key role of Fe-peroxo sites for the recognition of ethane. The high performance of Fe 2 (O 2 )(dobdc) for the ethane/ethylene separation has been validated by gas sorption isotherms, ideal adsorbed solution theory calculations, and simulated and experimental breakthrough curves. Through a fixed-bed column packed with this porous material, polymer-grade ethylene (99.99% pure) can be straightforwardly produced from ethane/ethylene mixtures during the first adsorption cycle, demonstrating the potential of Fe 2 (O 2 )(dobdc) for this important industrial separation with a low energy cost under ambient conditions.

• Topological cytonuclear discordance is commonly observed in plant phylogenetic and phylogeographic studies, yet few studies have attempted to detect two other forms of cytonuclear discordance (branch length and geographical) and to uncover the causes of the discordance. • We used the whole nuclear and chloroplast genome data from 80 individual Asian butternuts to reveal the pattern and processes of cytonuclear discordance. • Our findings indicate that the chloroplast genome had substantially deeper divergence (branch-length discordance) and a steeper cline in the contact zone (geographic discordance) compared with the nuclear genome. After various hypothesis have been tested, the results suggest that incomplete lineage sorting, positive selection and cytonuclear incompatibility are probably insufficient to explain this pattern. However, isolation-by-distance analysis and gene flow estimation point to a much higher level of gene flow by pollen compared with by seeds, which may have slowed down lineage divergence and mediated wider contact for nuclear genome compared with the chloroplast genome. • Altogether, this study highlights a critical role of sex-biased dispersal in causing discordance between the nuclear and plastid genome of Asian butternuts. Given its ubiquity among plants, asymmetric gene flow should be given a high priority in future studies of cytonuclear discordance.

Taxus, also known as “gold in plants” because of the famous agents with emphases on Taxol and Docetaxel, is a genus of the family Taxaceae, distributed almost around the world. The plants hold an important place in traditional medicine in China, and its products are used for treating treat dysuria, swelling and pain, diabetes, and irregular menstruation in women. In order to make a further study and better application of Taxus plants for the future, cited references from between 1958 and 2022 were collected from the Web of Science, the China National Knowledge Internet (CNKI), SciFinder, and Google Scholar, and the chemical structures, distribution, and bioactivity of flavonoids identified from Taxus samples were summed up in the research. So far, 59 flavonoids in total with different skeletons were identified from Taxus plants, presenting special characteristics of compound distribution. These compounds have been reported to display significant antibacterial, antiaging, anti-Alzheimer’s, antidiabetes, anticancer, antidepressant, antileishmaniasis, anti-inflammatory, antinociceptive and antiallergic, antivirus, antilipase, neuronal protective, and hepatic-protective activities, as well as promotion of melanogenesis. Flavonoids represent a good example of the utilization of the Taxus species. In the future, further pharmacological and clinical experiments for flavonoids could be accomplished to promote the preparation of relative drugs.

The bumblebee model is an extension of the Einstein–Maxwell theory that allows for the spontaneous breaking of the Lorentz symmetry of the spacetime. In this paper, we study the quasinormal modes of the spherical black holes in this model that are characterized by a global monopole. We analyze the two cases with a vanishing cosmological constant or a negative one (the anti-de Sitter case). We find that the black holes are stable under the perturbation of a massless scalar field. However, both the Lorentz symmetry breaking and the global monopole have notable impacts on the evolution of the perturbation. The Lorentz symmetry breaking may prolong or shorten the decay of the perturbation according to the sign of the breaking parameter. The global monopole, on the other hand, has different effects depending on whether a nonzero cosmological constant presences: it reduces the damping of the perturbations for the case with a vanishing cosmological constant, but has little influence for the anti-de Sitter case.

New evidence has emerged in recent years to suggest a strong link between the human gut microbiota, its metabolites, and various physiological aspects of hosts along with important pathophysiological dimensions of diseases. The research indicates that the gut microbiota can facilitate metabolite production in two ways: first, the resident species of the gut microbiota use the amino acids produced from food or the host as elements for protein synthesis, and second, conversion or fermentation are used to drive nutrient metabolism. Additionally, the gut microbiota can synthesize several nutritionally essential amino acids de novo, which is a potential regulatory factor in amino acid homeostasis. The primary objective of this review is to summarize the current literature relating to the ways in which microbial amino acids contribute to host amino acid homeostasis.

In this study, we determined the influences of different drying techniques such as natural air (ND), hot-air (HD), vacuum (VD), infrared (ID), microwave (MD), and freeze drying (FD) methods on the color, shrinkage ratio (SR), rehydration ratio (RR), firmness, crispness, microstructures, nutritional components, and free amino acids of Pleurotus eryngii . The results showed that these parameters were markedly influenced by different drying techniques. Among them, FD was the most effective drying method which retained the main characteristics of the fresh P. eryngii in above mentioned indexes, followed by ND and HD at 40 °C. Finally, despite the least drying time, MD treatment was not suitable to the drying process of P. eryngii slices since it damaged physicochemical properties and caused massive losses of the main nutrients and free amino acids. The results will provide a theoretical basis for industrial processing of P. eryngii .

Polychlorinated dibenzo- p -dioxins (PCDDs), as a class of persistent and highly toxic organic pollutants, have been posing a great threat to human health and the environment. The sensing of these compounds is important but challenging. Here, we report a highly stable zirconium-based metal-organic framework (MOF), Zr 6 O 4 (OH) 8 (HCOO) 2 (CPTTA) 2 (BUT-17) with one-dimensional hexagonal channels and phenyl-rich pore surfaces for the recognition and sensing of two representative PCDDs, 2,3-dichlorodibenzo- p -dioxin (BCDD) and 2,3,7,8-tetrachlorodibenzo- p -dioxin (TCDD), based on the fluorescence quenching. BUT-17 exhibits high sensing ability with the detection limits as low as 27 and 57 part per billion toward BCDD and TCDD, respectively, and is very selective as well without the interference of similar compounds. The recognition of BUT-17 toward BCDD is demonstrated by single-crystal structure of its guest-loaded phase, in which the fluorescence-quenched complexes form between the adsorbed BCDD molecules and the MOF host through π-π stacking and hydrogen bonding interactions. The sensing of polychlorinated dibenzo- p -dioxins (PCDDs) is important for the environment and public health but challenging to achieve. Here the authors report a stable zirconium-based metal-organic framework for the selective sensing of two representative PCCDs based on the fluorescence quenching method.

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.