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Besides, this method can be used to repair damaged CAN materials and efficiently recycle scrap CAN materials, which can effectively save resources and protect the environment. The universality and robustness of this strategy is expected to promote CAN application in broader functional polymer fields.In artificial photosynthesis, chemists are aiming to borrow principles from natural photosynthesis to develop photoelectrochemical cells (PEC) for water splitting. The water plastoquinone photo-oxidoreductase enzyme, also known as photosystem II, uses light to perform the four-electron, four-proton oxidation of water to dioxygen and stores reducing equivalents in reduced forms of quinones which are ultimately used in dark reactions for the synthesis of energy-rich molecules. We report a nano-structured semiconducting conjugated polymer based on poly(diphenylbutadiyne) (nano-PDPB) and its photocatalytic activities towards the water oxidation reaction under visible light irradiation when dispersed in water in the absence of any sacrificial agents or co-catalysts. Charge recovery at the nano-PDPB directly or delayed in time was exemplified by the reduction of quinone acting as a hydrogen reservoir. In the absence of quinones as electron acceptors H2O2 formation was detected, stemming from the partial reduction of O2.Synthetic ion channels may have applications in treating channelopathies and as new classes of antibiotics, particularly if ion flow through the channels can be controlled. Here we describe triazole-capped octameric α-aminoisobutyric acid (Aib) foldamers that "switch on" ion channel activity in phospholipid bilayers upon copper(ii) chloride addition; activity is "switched off" upon copper(ii) extraction. X-ray crystallography showed that CuCl2 complexation gave chloro-bridged foldamer dimers, with hydrogen bonds between dimers producing channels within the crystal structure. These interactions suggest a pathway for foldamer self-assembly into membrane ion channels. The copper(ii)-foldamer complexes showed antibacterial activity against B. megaterium strain DSM319 that was similar to the peptaibol antibiotic alamethicin, but with 90% lower hemolytic activity.For exploitation of a new class of aromatic micelles, we synthesized a bent pentacene-based amphiphilic molecule through Diels-Alder reaction. The amphiphiles bearing two trimethylammonium tethers assemble into a spherical aromatic micelle, with an average core diameter of 1.5 nm, in water at room temperature. The new aromatic micelle efficiently encapsulates perylene bisimide (PBI) dyes and graphene nanosheets (GNS) in water. Selleck Tacrolimus The encapsulated PBI dyes form a parallel stacked dimer, exhibiting characteristic absorption and emission bands. In addition, the encapsulated GNS are composed of few-layer graphene sheets with an average lateral size of ∼7 nm, as confirmed by Raman spectroscopy. The resultant, aqueous host-guest complexes are stable even after three weeks in water under ambient conditions.A new, air-stable, permanently porous uranium(iv) metal-organic framework U(bdc)2 (1, bdc2- = 1,4-benzenedicarboxylate) was synthesized and its H2 and CH4 adsorption properties were investigated. Low temperature adsorption isotherms confirm strong adsorption of both gases in the framework at low pressures. In situ gas-dosed neutron diffraction experiments with different D2 loadings revealed a rare example of cooperative framework contraction (ΔV = -7.8%), triggered by D2 adsorption at low pressures. This deformation creates two optimized binding pockets for hydrogen (Qst = -8.6 kJ mol-1) per pore, in agreement with H2 adsorption data. Analogous experiments with CD4 (Qst = -24.8 kJ mol-1) and N,N-dimethylformamide as guests revealed that the binding pockets in 1 adjust by selective framework contractions that are unique for each adsorbent, augmenting individual host-guest interactions. Our results suggest that the strategic combination of binding pockets and structural flexibility in metal-organic frameworks holds great potential for the development of new adsorbents with an enhanced substrate affinity.Photodynamic therapy has become an emerging strategy for the treatment of cancer. This technology relies on the development of photosensitizers (PSs) that convert molecular oxygen to cytotoxic reactive oxygen species upon exposure to light. In this study, we have developed a facile and general strategy for obtaining visible light/near-infrared-absorbing PSs by performing a simple sulfur-for-oxygen replacement within existing fluorophores. Thionation of carbonyl groups within existing fluorophore cores leads to an improvement of the singlet oxygen quantum yield and molar absorption coefficient at longer wavelengths (deep to 600-800 nm). Additionally, these thio-based PSs lack dark cytotoxicity but exhibit significant phototoxicity against monolayer cancer cells and 3D multicellular tumor spheroids with IC50 in the micromolar range. To achieve tumor-specific delivery, we have conjugated these thio-based PSs to an antibody and demonstrated their tumor-specific therapeutic activity.The incorporation of second-row transition metals into metal-organic frameworks could greatly improve the performance of these materials across a wide variety of applications due to the enhanced covalency, redox activity, and spin-orbit coupling of late-row metals relative to their first-row analogues. Thus far, however, the synthesis of such materials has been limited to a small number of metals and structural motifs. Here, we report the syntheses of the two-dimensional metal-organic framework materials (H2NMe2)2Nb2(Cl2dhbq)3 and Mo2(Cl2dhbq)3 (H2Cl2dhbq = 3,6-dichloro-2,5-dihydroxybenzoquinone), which feature mononuclear niobium or molybdenum metal nodes and are formed through reactions driven by metal-to-ligand electron transfer. Characterization of these materials via X-ray absorption spectroscopy suggests a local trigonal prismatic coordination geometry for both niobium and molybdenum, consistent with their increased covalency relative to related first-row transition metal compounds. A combination of vibrational spectroscopy, magnetic susceptibility, and electronic conductivity measurements reveal that these two frameworks possess distinct electronic structures.

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