The link between interfacial elasticity of foaming solutions and the elasticity and yield stress of their aqueous foams is probed for a variety of surfactant, block-copolymer, protein, food, and particle-stabilized (Pickering) foams. We measured interfacial tension σ and interfacial elastic moduli of foaming solutions in dilation E∞ as well as in shear at concentrations suitable for foaming and compared them to the shear modulus and yield stress of corresponding foams normalized by bubbles' Sauter radius R32 and foams' gas volume fraction. The interfacial shear modulus was only measurable for the foaming solutions including proteins or nanoparticles. For these systems the foam shear modulus scaled reasonably well with . The interfacial dilational modulus was accessible for all investigated systems and the foam shear modulus as well as yield stress scaled with a generalized Laplace pressure (σ + 2E∞)/R32. But foams stabilized by nanoparticles or aggregated proteins exhibited even higher shear modulus and yield stress values not captured by the proposed scaling with the generalized Laplace pressure and also show an unexpectedly high dependence of these characteristics on the gas volume fraction. We attribute this to attractive forces between particles and/or structure formation across the lamellae that become increasingly dominant as the lamellae narrow down during foam drainage.Accurate and specific analysis of adenosine triphosphate (ATP) expression levels in living cells can provide valuable information for understanding cell metabolism, physiological activities and pathologic mechanisms. Herein, DNA nanolantern-based split aptamer nanoprobes are prepared and demonstrated to work well for in situ analysis of ATP expression in living cells. The nanoprobes, which carry multiple split aptamer units on the surface, are easily and inexpensively prepared by a "one-pot" assembly reaction of four short oligonucleotide strands. A series of characterization experiments verify that the nanoprobes have good monodispersity, strong biostability, high cell internalization efficiency, and fluorescence resonance energy transfer (FRET)-based ratiometric response to ATP in the concentration range covering the entire intracellular ATP expression level. By changing the intracellular ATP level via different treatments, the nanoprobes are demonstrated to show excellent performance in intracellular ATP expression analysis, giving a highly ATP concentration-dependent ratiometric fluorescence signal output. ATP-induced formation of large-sized DNA aggregates not only amplifies the FRET signal output, but also makes in situ ATP-imaging analysis in living cells possible. In situ responsive crosslinking of nanoprobes also makes them capable of lighting up the mitochondria of living cells. By simply changing the split aptamer sequence, the proposed DNA nanolantern-based split aptamer strategy might be easily extended to other targets.Layered double hydroxides (LDHs) with high theoretical specific capacity have been considered as one of the most promising candidates for high-performance supercapacitors. https://www.selleckchem.com/products/gdc-0068.html However, the low electronic conductivity and insufficient active sites hinder the further large-scale application of bulk LDHs. Here, we successfully synthesized heterostructured Co-Zn LDH@Co(H2PO4)2 nanoflowers by a simple hydrothermal method. As the amount of Co(H2PO4)2 in the whole heterostructure increases, the nanosheets steadily evolve into nanoflowers with a high surface area, providing more electrochemically active sites. Moreover, the built-in electric field formed between Co-Zn LDH and Co(H2PO4)2 improves the conductivity of the composite electrode. As a result, the as-prepared Co-Zn LDH@Co(H2PO4)2 shows a high specific capacity of 919 C g-1 at a current density of 1 A g-1. A hybrid supercapacitor (HSC) with activated carbon (AC) as the negative electrode and Co-Zn LDH@Co(H2PO4)2 as the positive electrode delivers an energy density of 30.4 W h kg-1 at a power density of 400 W kg-1, and 95.3% of the initial capacity is retained after 5000 cycles. This study provides a novel synthesis strategy for constructing heterojunctions to enhance the energy storage properties of LDH-based materials.The successful synthesis of a 1T'/2H MoS2 heterophase bilayer offers potential building blocks for constructing novel nanoelectronic and optoelectronic devices. Here, first principles calculations are applied to explore and modulate its contact nature. The calculated results show a finite Schottky barrier of ∼0.56 eV, and a dominant tunneling barrier of ∼2 eV exists at the contact interface of the 1T'/2H MoS2 heterophase bilayer. The Schottky barrier can be eliminated by adatoms and strains. Although the two strategies have an insignificant effect on the dominant tunneling barrier, they alter the regions with local potentials lower than that of the inter-layer gap related barrier.The coexistence of field-induced slow magnetic relaxation and moderately large magnetocaloric efficiency in the supra-Kelvin temperature region occurs in the 2D compound [Gd(ox)3(H2O)6]n·4nH2O (1), a feature that can be exploited in the proof-of-concept design of a new class of slow-relaxing magnetic materials for cryogenic magnetic refrigeration.The energy barrier and hysteresis temperature in two benchtop-stable D5h-symmetry HoIII single-ion magnets were significantly enhanced via the variation of the halogen anion. The coexistence of a high energy barrier of 418 K and hysteresis temperature of 15 K was observed in the bromide-ion containing HoIII single-ion magnet.Gyroid materials have received considerable attention from scientists due to their beautiful structures and advanced functions. On the other side, metal-organic frameworks are inorganic-organic hybrid crystalline porous materials with atomic precision, and can provide good structural models and rich topologies for gyroid materials. In this review, we will briefly introduce the structures of gyroid metal-organic frameworks and their topologies. In addition, their applications in gas adsorption, catalysis, sensors, and luminescent materials are also discussed in detail.
The link between interfacial elasticity of foaming solutions and the elasticity and yield stress of their aqueous foams is probed for a variety of surfactant, block-copolymer, protein, food, and particle-stabilized (Pickering) foams. We measured interfacial tension σ and interfacial elastic moduli of foaming solutions in dilation E∞ as well as in shear at concentrations suitable for foaming and compared them to the shear modulus and yield stress of corresponding foams normalized by bubbles' Sauter radius R32 and foams' gas volume fraction. The interfacial shear modulus was only measurable for the foaming solutions including proteins or nanoparticles. For these systems the foam shear modulus scaled reasonably well with . The interfacial dilational modulus was accessible for all investigated systems and the foam shear modulus as well as yield stress scaled with a generalized Laplace pressure (σ + 2E∞)/R32. But foams stabilized by nanoparticles or aggregated proteins exhibited even higher shear modulus and yield stress values not captured by the proposed scaling with the generalized Laplace pressure and also show an unexpectedly high dependence of these characteristics on the gas volume fraction. We attribute this to attractive forces between particles and/or structure formation across the lamellae that become increasingly dominant as the lamellae narrow down during foam drainage.Accurate and specific analysis of adenosine triphosphate (ATP) expression levels in living cells can provide valuable information for understanding cell metabolism, physiological activities and pathologic mechanisms. Herein, DNA nanolantern-based split aptamer nanoprobes are prepared and demonstrated to work well for in situ analysis of ATP expression in living cells. The nanoprobes, which carry multiple split aptamer units on the surface, are easily and inexpensively prepared by a "one-pot" assembly reaction of four short oligonucleotide strands. A series of characterization experiments verify that the nanoprobes have good monodispersity, strong biostability, high cell internalization efficiency, and fluorescence resonance energy transfer (FRET)-based ratiometric response to ATP in the concentration range covering the entire intracellular ATP expression level. By changing the intracellular ATP level via different treatments, the nanoprobes are demonstrated to show excellent performance in intracellular ATP expression analysis, giving a highly ATP concentration-dependent ratiometric fluorescence signal output. ATP-induced formation of large-sized DNA aggregates not only amplifies the FRET signal output, but also makes in situ ATP-imaging analysis in living cells possible. In situ responsive crosslinking of nanoprobes also makes them capable of lighting up the mitochondria of living cells. By simply changing the split aptamer sequence, the proposed DNA nanolantern-based split aptamer strategy might be easily extended to other targets.Layered double hydroxides (LDHs) with high theoretical specific capacity have been considered as one of the most promising candidates for high-performance supercapacitors. https://www.selleckchem.com/products/gdc-0068.html However, the low electronic conductivity and insufficient active sites hinder the further large-scale application of bulk LDHs. Here, we successfully synthesized heterostructured Co-Zn LDH@Co(H2PO4)2 nanoflowers by a simple hydrothermal method. As the amount of Co(H2PO4)2 in the whole heterostructure increases, the nanosheets steadily evolve into nanoflowers with a high surface area, providing more electrochemically active sites. Moreover, the built-in electric field formed between Co-Zn LDH and Co(H2PO4)2 improves the conductivity of the composite electrode. As a result, the as-prepared Co-Zn LDH@Co(H2PO4)2 shows a high specific capacity of 919 C g-1 at a current density of 1 A g-1. A hybrid supercapacitor (HSC) with activated carbon (AC) as the negative electrode and Co-Zn LDH@Co(H2PO4)2 as the positive electrode delivers an energy density of 30.4 W h kg-1 at a power density of 400 W kg-1, and 95.3% of the initial capacity is retained after 5000 cycles. This study provides a novel synthesis strategy for constructing heterojunctions to enhance the energy storage properties of LDH-based materials.The successful synthesis of a 1T'/2H MoS2 heterophase bilayer offers potential building blocks for constructing novel nanoelectronic and optoelectronic devices. Here, first principles calculations are applied to explore and modulate its contact nature. The calculated results show a finite Schottky barrier of ∼0.56 eV, and a dominant tunneling barrier of ∼2 eV exists at the contact interface of the 1T'/2H MoS2 heterophase bilayer. The Schottky barrier can be eliminated by adatoms and strains. Although the two strategies have an insignificant effect on the dominant tunneling barrier, they alter the regions with local potentials lower than that of the inter-layer gap related barrier.The coexistence of field-induced slow magnetic relaxation and moderately large magnetocaloric efficiency in the supra-Kelvin temperature region occurs in the 2D compound [Gd(ox)3(H2O)6]n·4nH2O (1), a feature that can be exploited in the proof-of-concept design of a new class of slow-relaxing magnetic materials for cryogenic magnetic refrigeration.The energy barrier and hysteresis temperature in two benchtop-stable D5h-symmetry HoIII single-ion magnets were significantly enhanced via the variation of the halogen anion. The coexistence of a high energy barrier of 418 K and hysteresis temperature of 15 K was observed in the bromide-ion containing HoIII single-ion magnet.Gyroid materials have received considerable attention from scientists due to their beautiful structures and advanced functions. On the other side, metal-organic frameworks are inorganic-organic hybrid crystalline porous materials with atomic precision, and can provide good structural models and rich topologies for gyroid materials. In this review, we will briefly introduce the structures of gyroid metal-organic frameworks and their topologies. In addition, their applications in gas adsorption, catalysis, sensors, and luminescent materials are also discussed in detail.
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