The realization of porous materials for highly selective separation of acetylene (C2H2) from various other gases (e.g., carbon dioxide and ethylene) by adsorption is of prime importance but ...challenging in the petrochemical industry. Herein, a chemically stable Hofmann‐type metal−organic framework (MOF), Co(pyz)Ni(CN)4 (termed as ZJU‐74a), that features sandwich‐like binding sites for benchmark C2H2 capture and separation is reported. Gas sorption isotherms reveal that ZJU‐74a exhibits by far the record C2H2 capture capacity (49 cm3 g−1 at 0.01 bar and 296 K) and thus ultrahigh selectivity for C2H2/CO2 (36.5), C2H2/C2H4 (24.2), and C2H2/CH4 (1312.9) separation at ambient conditions, respectively, of which the C2H2/CO2 selectivity is the highest among all the robust MOFs reported so far. Theoretical calculations indicate that the oppositely adjacent nickel(II) centers together with cyanide groups from different layers in ZJU‐74a can construct a sandwich‐type adsorption site to offer dually strong and cooperative interactions for the C2H2 molecule, thus leading to its ultrahigh C2H2 capture capacity and selectivities. The exceptional separation performance of ZJU‐74a is confirmed by both simulated and experimental breakthrough curves for 50/50 (v/v) C2H2/CO2, 1/99 C2H2/C2H4, and 50/50 C2H2/CH4 mixtures under ambient conditions.
A chemically stable Hofmann‐type metal−organic framework is realized for benchmark acetylene capture capacity and separation, mainly attributed to the unique sandwich‐like binding environments constructed by the oppositely adjacent open metal centers and cyanide groups from the two different Ni(CN)42− building units, thus affording a record‐high acetylene uptake at 0.01 bar and very high selectivities for acetylene‐related separation applications.
In Einstein-Æther theory, the Lorentz symmetry is locally broken in the high-energy regime due to the presence of the Æther field. This shall leave significant imprint on astronomical observation. In ...this paper, we investigate the optical appearance of two types of the static and spherically symmetric black holes in Einstein-Æther theory. Via Euler-Lagrange equation, we obtain the equations of motion of the photon and calculate the total deflection angle of the photon trajectory around the black hole. By classifying the light rays with the total number of orbits, we study the effects of coupling constants on the direct image, lensing ring, and photon ring. The features of the light trajectories are also investigated by comparing with the Einstein-Æther theory and general relativity. Moreover, we also show the explicit optical appearance of black holes surrounded by thin disk emissions with three characteristic emitted models. The results indicate that the direct image gives the main contribution to the total flux, and the lensing ring just gives a very small contribution, whereas the role of the photon ring is negligible. The optical appearances are also found to significantly rely on these coupling constants.
Developing porous materials to overcome the trade‐off between adsorption capacity and selectivity for C2H2/CO2 separation remains a challenge. Herein, we report a stable HKUST‐1‐like MOF (ZJU‐50a), ...featuring large cages decorated with high density of supramolecular binding sites to achieve both high C2H2 storage and selectivity. ZJU‐50a exhibits one of the highest C2H2 storage capacity (192 cm3 g−1) and concurrently high C2H2/CO2 selectivity (12) at 298 K and 1 bar. Single‐crystal X‐ray diffraction studies on gas‐loaded ZJU‐50a crystal unveil that the incorporated supramolecular binding sites can selectively take up C2H2 molecule but not CO2 to result in both high C2H2 storage and selectivity. Breakthrough experiments validated its separation performance for C2H2/CO2 mixtures, providing a high C2H2 recovery capacity of 84.2 L kg−1 with 99.5 % purity. This study suggests a novel strategy of engineering supramolecular binding sites into MOFs to overcome the trade‐off for this separation.
We developed a novel strategy by engineering abundant supramolecular binding sites into a chemically stable HKUST‐1‐like MOF (ZJU‐50a) to achieve simultaneously high C2H2 storage and selectivity, breaking the trade‐off between adsorption capacity and selectivity for C2H2/CO2 separation.
Abstract
Early Cretaceous mafic rocks are first reported in the northern Guangxi region from the western Qin-Hang belt in the interior South China Block. A systematic investigation of zircon U–Pb ...dating, whole-rock geochemistry, Sm–Nd isotopes and zircon Hf–O isotopes for these mafic rocks reveals their petrogenesis and the mantle composition as well as a new window to reconstruct lithospheric evolution in interior South China Block during Late Mesozoic. Zircon U–Pb dating yielded ages of 131 ± 2 Ma to 136 ± 2 Ma for diabase and gabbro from Baotan area, indicating the first data for Early Cretaceous mafic magmatism in the western Qing-Hang belt. These mafic rocks show calc-alkaline compositions, arc-like trace element distribution patterns, low zircon ε
Hf
(
t
) of − 9.45 to − 6.17 and high δ
18
O values of + 5.72 to + 8.09‰, as well as low whole-rock ε
Nd
(
t
) values of − 14.27 to − 9.53. These data suggest that the studied mafic rocks are derived from an ancient lithospheric mantle source that was metasomatized during Neoproterozoic subduction. Thus, the occurrence of these mafic rocks indicates a reactivation of Neoproterozoic subducted materials during an extension setting at Late Mesozoic in the western Qin-Hang belt, an old suture zone that amalgamates the Yangtze and Cathaysia blocks.
The amino acid sequence enriched with proline (P), glutamic acid (E), serine (S), and threonine (T) (PEST) is a signal‐transducing agent providing unique features to its substrate nuclear proteins ...(PEST‐NPs). The PEST motif is responsible for particular posttranslational modifications (PTMs). These PTMs impart distinct properties to PEST‐NPs that are responsible for their activation/inhibition, intracellular localization, and stability/degradation. PEST‐NPs participate in cancer metabolism, immunity, and protein transcription as oncogenes or as tumor suppressors. Gene‐based therapeutics are getting the attention of researchers because of their cell specificity. PEST‐NPs are good targets to explore as cancer therapeutics. Insights into PTMs of PEST‐NPs demonstrate that these proteins not only interact with each other but also recruit other proteins to/from their active site to promote/inhibit tumors. Thus, the role of PEST‐NPs in cancer biology is multivariate. It is hard to obtain therapeutic objectives with single gene therapy. An especially designed combination gene therapy might be a promising strategy in cancer treatment. This review highlights the multifaceted behavior of PEST‐NPs in cancer biology. We have summarized a number of studies to address the influence of structure and PEST‐mediated PTMs on activation, localization, stability, and protein–protein interactions of PEST‐NPs. We also recommend researchers to adopt a pragmatic approach in gene‐based cancer therapy.
1.PEST (proline, glutamic acid, serine, and threonine) motif is responsible for particular posttranslational modifications (PTMs) in their substrate nuclear proteins.
2.Insights into PTMs of nuclear proteins demonstrate that these proteins not only interact with each other but also recruit other proteins to/from their active site to promote/inhibit tumors.
3.PEST sequence enriched nuclear proteins (PEST‐NPs) are multivariate in their behavior.
Lysine‐specific demethylase 1 (LSD1) is a flavin adenine dinucleotide (FAD) dependent monoamine oxidase (MAO) that erases the mono‐, and dimethylation of histone 3 lysine 4 (H3K4), resulting in the ...suppression of target gene transcriptions. Besides, it can also demethylate some nonhistone substrates to regulate their biological functions. As reported, LSD1 is widely upregulated and plays a key role in several kinds of cancers, pharmacological or genetic ablation of LSD1 in cancer cells suppresses cell aggressiveness by several distinct mechanisms. Therefore, numerous LSD1 inhibitors, including covalent and noncovalent, have been developed and several of them have entered clinical trials. Herein, we systemically reviewed and discussed the biological function of LSD1 in tumors, lymphocytes as well as LSD1‐targeting inhibitors in clinical trials, hoping to benefit the field of LSD1 and its inhibitors.
Most tin deposits in the world are genetically related to tin granite and form during complex magmatic-hydrothermal processes. Zircon is a common accessory mineral in granite and related ore systems ...and can host a number of ore metals, such as Sn, W, Nb, Ta, U and Th, in its crystal lattice. However, whether metal enrichment/depletion can trace ore-forming processes is still unclear. Here, we report that the metal concentrations in various types of zircons from the Mopanshan tin granites in the southern Great Xing'an Range (Northern China) can be used as good indicators of fluid metasomatism and Sn mineralization. Two lithological zones are developed in the Mopanshan pluton, including porphyritic syenogranite (PG) in the center and fine-grained syenogranite (FG) at the margin. Zircons in the PG (PGZ-1, PGZ-2, and PGZ-3) are all magmatic in origin, while zircons in the FG can be categorized into magmatic zircons (FGZ-1 and FGZ-2) and metasomatic zircons (FGZ-3). The PGZ-1 and FGZ-1 grains are transparent prismatic crystals with bright oscillatory zonation, whereas the PGZ-2 grains are murky crystals with dark oscillatory zonation. PGZ-3 and FGZ-2 grains occur as overgrowths of previously formed zircon (PGZ-1, PGZ-2, and FGZ-1) or as brown individual crystals, showing dark and homogeneous cathodoluminescence (CL) textures. The metasomatic FGZ-3 grains are translucent-opaque porous crystals with vermicular CL zonation and commonly replace FGZ-2. The trace element compositions of magmatic zircons are completely melt controlled, providing a record of magmatic evolution as a constant decrease in Zr/Hf ratios and a gradual increase in Th, U, Nb, and Ta contents. Moreover, the structure of magmatic zircons transforms from a crystalline state to an amorphous state as a consequence of radioactive decay of U and Th. A coupled dissolution-reprecipitation process is proposed for the formation of metasomatic FGZ-3. The reactive fluid is the magmatic fluid that exsolved from the melt in the late magmatic stage. The magmatic fluid replaced biotite and rare earth phosphates (mainly monazite and apatite) enclosed within biotite, resulting in significant amounts of Nb, Ta, Sn, P, Al, Ca, Fe, and REEs, which subsequently reacted with the FGZ-2 zircons to leach Th, U, Y, and HREEs. Eventually, REEs, Y, Th, and U in the fluid combined with P to form monazite and xenotime, while the other elements partially precipitated with the crystallization of the FGZ-3 zircons. Although the alteration of biotite only released approximately 190 ppm of Sn into the fluid, this is still a significant Sn source for the Sn deposits surrounding the Mopanshan pluton, taking the granite size (∼50 km2) and the volume proportion of biotite (∼5%) into account. Furthermore, based on previous studies on tourmaline from the Mopanshan granite and regional geochemistry, it may be inferred that the addition of wall rock components may also play an important role in Sn mineralization.
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•Magmatic and metasomatic zircons have been identified in the Mopanshan granite.•Formation of metasomatic zircon is due to a dissolution-reprecipitation process.•Zircon records the enrichment of Sn during magmatic-hydrothermal process.•The release of Sn by biotite alteration is a significant Sn source for Sn deposits.
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