Lauritzennorris4342
Electrically conductive metal-organic frameworks (MOFs) provide a rare example of porous materials that can efficiently transport electrical current, a combination that is favorable for a variety of technological applications. The vast majority of such MOFs are highly anisotropic in both their structures and properties Only two electrically conductive MOFs reported to date exhibit cubic structures that enable isotropic charge transport. Here we report a new family of intrinsically porous frameworks made from rare-earth nitrates and hexahydroxytriphenylene. The materials feature a novel hexanuclear secondary building unit and form cubic, porous, and intrinsically conductive structures, with electrical conductivities reaching 10-5 S/cm and surface areas of up to 780 m2/g. By expanding the list of MOFs with isotropic charge transport, these results will help us to improve our understanding of design strategies for porous electronic materials.A versatile gold(I)-catalyzed cross-coupling reaction of 3-diazooxindoles with diazoesters has been presented, affording (E)-3-alkylideneoxindoles stereoselectively. Density functional theory (DFT) calculations rationalized the chemo- and stereoselectivity of the reaction, which was in good agreement with experimental observations. In addition, (E)-3-alkylideneoxindoles were converted into their (Z)-isomers under UV-irradiation facilely, indicating the great advantage of this approach in stereoselective synthesis of both (E)- and (Z)-3-alkylideneoxindoles.LTFPGSAED (P7) is a multifunctional hypocholesterolemic and hypoglycemic lupin peptide. While assessing its angiotensin-converting enzyme (ACE) inhibitory activity, it was more effective in intestinal Caco-2 cells (IC50 of 13.7 μM) than in renal HK-2 cells (IC50 of 79.6 μM). This discrepancy was explained by the metabolic transformation mediated by intestinal peptidases, which produced two main detected peptides, TFPGSAED and LTFPG. Indeed LTFPG, dynamically generated by intestinal dipeptidyl peptidase IV as well as its parent peptide P7 were linearly absorbed by mature Caco-2 cells. An in silico study demonstrated that the metabolite was a better ligand of the ACE enzyme than P7. These results are in agreement with an in vivo study, previously performed by Aluko et al., which has shown that LTFPG is an effective hypotensive peptide. Our work highlights the dynamic nature of bioactive food peptides that may be modulated by the metabolic activity of intestinal cells.In this study, we propose a new concept of vertically aligned 2D covalent organic framework (COF) layers forming a membrane for efficient gas separation on the basis of precise size exclusion. Gas transport takes place through the COF interlayer space (typically 0.3-0.4 nm) rather than through the nanometer-sized pore apertures. Construction of such a unique membrane architecture was implemented via in situ oriented growth of 2D COFs inside a skeleton of vertically aligned CoAl-layered double hydroxide (LDH) nanosheets. The resultant vertical COF-LZU1 membrane exhibits a high H2 permeance of ∼3600 GPU together with a desirable separation selectivity for gas mixtures such as H2/CO2 (31.6) and H2/CH4 (29.5), thus surpassing the 2008 Robeson upper bounds. The universality of this approach was demonstrated by successfully producing two types of high-quality vertical COF membranes with superior performance as well as outstanding running stability.Two new highly charged [2]catenanes-namely, mHe[2]C·6PF6 and mHo[2]C·6PF6-were synthesized by exploiting radical host-guest templation between derivatives containing BIPY•+ radical cations and the meta analogue of cyclobis(paraquat-p-phenylene). In contrast to related [2]catenanes that have been isolated as air-stable monoradicals, both mHe[2]C·6PF6 and mHo[2]C·6PF6 exist as air-stable singlet bisradicals, as evidenced by both X-ray crystallography in the solid state and EPR spectroscopy in solution. SBI-0206965 price Electrochemical studies indicate that the first two reduction peaks of these two [2]catenanes are shifted significantly to more positive potentials, a feature which is responsible for their extraordinary stability in air. The mixed-valence nature of the mono- and bisradical states endows them with unique NIR absorption properties, e.g., NIR absorption bands for the mono- and bisradical states observed at ∼1800 and ∼1450 nm, respectively. These [2]catenanes are potentially useful in applications that include NIR photothermal conversion, UV-vis-NIR multiple-state electrochromic materials, and multiple-state memory devices. Our findings highlight the principle of "mechanical-bond-induced stabilization" as an efficient strategy for designing persistent organic radicals.The assembly of two-dimensional (2D) nanosheets into three-dimensional (3D) well-organized superstructures is one of the key topics in materials chemistry and physics, due to their potential applications in various fields. Herein, starting from the crystalline metal-organic framework (MOF) particles, a spherical superstructure consisting of metal-organic framework nanosheets (SS-MOFNSs) is synthesized via a simple solvothermal transformation process. After pyrolysis and nitrogenization in ammonia, the SS-MOFNSs is further transformed into the spherical superstructure consisting of boron nitride nanosheets (SS-BNNSs), which preserve the original spherical superstructure morphology. Taking advantage of this unique superstructure, the resulting SS-BNNSs exhibit excellent catalytic activity for selective oxidative dehydrogenation of propane to produce propylene and ethylene. The results of this work provide a novel synthetic strategy to fabricate 3D spherical superstructures consisting of 2D nanosheets for high-performance applications in catalysis, energy storage, as well as other related fields.The limitations of the Haber-Bosch reaction, particularly high-temperature operation, have ignited new interests in low-temperature ammonia-synthesis scenarios. Ambient N2 electroreduction is a compelling alternative but is impeded by a low ammonia production rate (mostly 120 mA cm-2 current densities for 100 h due to the robust subsurface Ru-O coordination. These findings highlight the potential of nitrate electroreduction in real-world, low-temperature ammonia synthesis.