Activity

Nacre’s natural design consists of a perfect hierarchical assembly that resembles a brick-and-mortar structure with synergistic stiffness and toughness. The field of bioinspired materials often provides attractive architecture and engineering pathways which allow to explore outstanding property areas. However, the study of nacre-mimetic materials should not be limited to the design of its architecture but ought to include the understanding, operation, and improvement of internal interactions between their components. Here, we introduce a vitrimer prepolymer system that, once integrated into the nacre-mimetic nanocomposites, cures and cross-links with the presence of Lewis acid catalyst and further manifests associative dynamic exchange reactions. Bond exchanges are controllable by molecular composition and catalyst content and characterized by creep, shear-lag, and shape-locking tests. We exploit the vitrimer properties by laminating ca. 70 films into thick bulk materials, and characterize the flexural resistance and crack propagation. More importantly, we introduce recycling by grinding and hot-pressing. The recycling for highly reinforced nacre-mimetic nanocomposites is critically enabled by the vitrimer chemistry and improves the sustainability of bioinspired nanocomposites in cyclic economy. Finally, we integrate photothermal converters into the structures and use laser irradiation as external trigger to activate the vitrimer exchange reactions.In view of the increasingly severe global warming and ocean acidification caused by CO2 emissions, we report a new procedure, named “reactive separation”, to capture CO2. We used advanced Monte Carlo and molecular dynamics methods to simulate the water-gas shift reaction in single-walled carbon nanotubes. We found that (11,11) carbon nanotubes with a diameter of 0.75 nm have the best ability to capture CO2 generated in the water-gas shift reaction. When the feed water-gas ratio is 11, the pressure is 3 MPa, and the temperature is 473 K, the storage capacity of CO2 reaches 2.18 mmol/g, the molar fraction of CO2 and H2 inside the carbon nanotube is 0.87 and 0.09, respectively, the conversion of CO in the pore is as high as 97.6%, and the CO2/H2 separation factor is 10.3. Therefore, utilizing the reaction and separation coupling effect of carbon nanotubes to adsorb and store the product CO2 formed in the water-gas shift reaction, while separating the generated clean energy gas H2, is a promising strategy for developing novel CO2 capture technologies.68Ga-PET has emerged as an important diagnostic tool for precise detection and monitoring of oncological situations. Availability, cost, and radiosynthesis procedure are determining steps for success of a radioisotope/radiopharmaceutical in nuclear medicine. Availability of 68Ga from a 68Ge/68Ga generator containing a long-lived parent radioisotope (68Ge t1/2 = 271 days) and an inexpensive, simplified production of 68Ga-radiopharmaceuticals through kit methodology has allowed smooth accommodation of 68Ga-PET in clinics. The uncomplicated formulation of 68Ga-radiopharmaceuticals from a lyophilized, cold kit is an impending breakthrough in clinical PET. The huge success of 68Ga in neuroendocrine tumor and prostate cancer imaging along with the regulatory approval of respective cold kits has opened a pathway for development of kits for other evolving radiotracers. There is a definite scope for increased participation of commercial manufacturers and distributors of cold kits to spread the potential of 68Ga worldwide across all the geographical locations and satellite centers.Among the recent developments in metal-organic frameworks (MOFs), porous layered coordination polymers (CPs) have garnered attention due to their modular nature and tunable structures. These factors enable a number of properties and applications, including gas and guest sorption, storage and separation of gases and small molecules, catalysis, luminescence, sensing, magnetism, and energy storage and conversion. Among MOFs, two-dimensional (2D) compounds are also known as 2D CPs or 2D MOFs. Since the discovery of graphene in 2004, 2D materials have also been widely studied. Several 2D MOFs are suitable for exfoliation as ultrathin nanosheets similar to graphene and other 2D materials, making these layered structures useful and unique for various technological applications. Furthermore, these layered structures have fascinating topological networks and entanglements. This review provides an overview of different aspects of 2D MOF layered architectures such as topology, interpenetration, structural transformations, properties, and applications.The allene functionality has participated in one of the most exciting voyages in organic chemistry, from chemical curiosities to a recurring building block in modern organic chemistry. In the last decades, a special kind of allene, namely, allenol, has emerged. EGFR activation Allenols, formed by an allene moiety and a hydroxyl functional group with diverse connectivity, have become common building blocks for the synthesis of a wide range of structures and frequent motif in naturally occurring systems. The synergistic effect of the allene and hydroxyl functional groups enables allenols to be considered as a unique and sole functionality exhibiting a special reactivity. This Review summarizes the most significant contributions to the chemistry of allenols that appeared during the past decade, with emphasis on their synthesis, reactivity, and occurrence in natural products.A novel tetrahedral μ-AsO4-bridging hexadecanuclear Ni-substituted silicotungstate (ST) Na21H10[(AsO4)Ni8(OH)6(H2O)2(CO3)2(A-α-SiW9O34)22]·60H2O (1) was made by the reactions of trivacant [A-α-SiW9O34]10- (SiW9) units with Ni2+ cations and Na3AsO4·12H2O and characterized by IR spectrometry, elemental analysis, thermogravimetric analysis (TGA), and powder X-ray diffraction (PXRD). 1 contains a novel polyoxoanion [(AsO4)Ni8(OH)6(H2O)2(CO3)2(A-α-SiW9O34)22]31- built by four trivacant Keggin [A-α-SiW9O34]10- fragments linked through an unprecedented [(AsO4)Ni8(OH)6(H2O)2(CO3)22]9+ cluster, where the tetrahedral AsO4 acts as an exclusively μ2-bridging unit to link multiple Ni centers; such a connection mode appears for the first time in polyoxometalate chemistry. Furthermore, the electrochemical and catalytic oxidation properties of compound 1 have been investigated.