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Graphite is a widely used oxygen impurity-removing additive and a property-tuning second phase for diboride and carbide-based ultrahigh temperature ceramics (UHTCs). In recent years, high-entropy diboride (HEB) ceramics have attracted much attention for the development of better UHTCs. However, oxide impurity generally inhibits their densification and harms their properties. Here, (Ti 0.2 Zr 0.2 Hf 0.2 Nb 0.2 Ta 0.2)B 2 ceramics added with different contents of graphite (HEB- x C, x = 0, 1, 2.5, 5, 10, 20 vol%) were prepared by spark plasma sintering. It was found that the added graphite acted as an oxygen-removing agent and the oxide impurity phase t -(Zr, Hf)O 2 was converted to the (Hf, Ta)C-based solid solution carbide. With the increase in graphite content, the relative density increased from 89.4% for HEB-0 C to 100% for HEB-10 C. Based on the evaluated properties of the prepared specimens, including Young's modulus, hardness, toughness, and thermal conductivity, the added graphite with an optimized content is important for a given started powder and processing to achieve good and balanced material properties. [ABSTRACT FROM AUTHOR]

The precise control of complex quantum mechanical systems can unlock applications ranging from quantum simulation to quantum computation. Controlling strongly interacting many-body systems often relies on Floquet Hamiltonian engineering that is achieved by fast switching between Hamiltonian primitives via external control. For example, in our solid-state NMR system, we perform quantum simulation by modulating the natural Hamiltonian with control pulses. As the Floquet heating errors scale with the interpulse delay, δ t , it is favorable to keep δ t as short as possible, forcing our control pulses to be short duration and high power. Additionally, high-power pulses help to minimize undesirable evolution from occurring during the duration of the pulse. However, such pulses introduce an appreciable phase-transient control error, a form of unitary error. In this work, we detail our ability to diagnose the error, calibrate its magnitude, and correct it for π / 2 -pulses of arbitrary phase. We demonstrate the improvements gained by correcting for the phase transient error, using a method which we call the "frame-change technique", in a variety of experimental settings of interest. Given that the correction mechanism adds no real control overhead, we recommend that any resonance probe be checked for these phase transient control errors, and correct them using the frame-change technique. [Display omitted] • High-power pulses are vital components of high-fidelity quantum simulation. • Phase-transient errors can be quickly calibrated with experiments on nuclear spins. • We introduce a technique to analytically correct the phase-transient error. • The frame-change technique introduces no additional control overhead. • We demonstrate the frame-change corrected improvements experimentally. [ABSTRACT FROM AUTHOR]

Design of heterogeneous catalyst to achieve efficient conversion of biomass to high added-value chemicals is still very attractive. Herein, taking industrially important selective hydrogenation of furfural to furfuryl alcohol as an example, the designed amorphized HA zeolite encapsulation of platinum clusters (denoted as Pt@HA) exhibited excellent catalytic selectivity at totally conversion of the reactant furfural, along with good reusability and poison resistance ability. The selected amorphized HA zeolite with very small pore size constrained the reactant furfural to be reacted through hydrogen spillover process at zeolite surface, instead of to be adsorbed and activated onto Pt surface. Resulting from the stronger interaction between nucleophilic oxygen atom of aldehyde group and acid site at HA zeolite surface than that of furan ring group, furfural preferred to adsorb onto Pt@HA surface with the end of aldehyde group rather than the end of furan ring group, thus facilitating the spilled H atom to react with aldehyde group to give desired furfuryl alcohol product exclusively. [Display omitted] • Pt@HA exhibited remarkable catalytic property in hydrogenation of furfural to furfuryl alcohol via hydrogen spillover. • Spillover process disfavored activation of aldehyde group and furan ring simultaneously in one furfural molecule. • Acid sites on HA zeolite surface promoted adsorption of aldehyde group to facilitate its hydrogenation process. [ABSTRACT FROM AUTHOR]

Upon pathogenic stimulation, activated neutrophils release nuclear DNA into the extracellular environment, forming web‐like DNA structures known as neutrophil extracellular traps (NETs), which capture and kill bacteria, fungi, and cancer cells. This phenomenon is commonly referred to as NETosis. Inspired by this, we introduce a cell surface‐constrained web‐like framework nucleic acids traps (FNATs) with programmable extracellular recognition capability and cellular behavior modulation. This approach facilitates dynamic key chemical signaling molecule recognition such as adenosine triphosphate (ATP), which is elevated in the extracellular microenvironment, and triggers FNA self‐assembly. This, in turn, leads to in situ tightly interwoven FNAs formation on the cell surface, thereby inhibiting target cell migration. Furthermore, it activates a photosensitizer‐capturing switch, chlorin e6 (Ce6), and induces cell self‐destruction. This cascade platform provides new potential tools for visualizing dynamic extracellular activities and manipulating cellular behaviors using programmable in situ self‐assembling DNA molecular devices. [ABSTRACT FROM AUTHOR]

Upon pathogenic stimulation, activated neutrophils release nuclear DNA into the extracellular environment, forming web‐like DNA structures known as neutrophil extracellular traps (NETs), which capture and kill bacteria, fungi, and cancer cells. This phenomenon is commonly referred to as NETosis. Inspired by this, we introduce a cell surface‐constrained web‐like framework nucleic acids traps (FNATs) with programmable extracellular recognition capability and cellular behavior modulation. This approach facilitates dynamic key chemical signaling molecule recognition such as adenosine triphosphate (ATP), which is elevated in the extracellular microenvironment, and triggers FNA self‐assembly. This, in turn, leads to in situ tightly interwoven FNAs formation on the cell surface, thereby inhibiting target cell migration. Furthermore, it activates a photosensitizer‐capturing switch, chlorin e6 (Ce6), and induces cell self‐destruction. This cascade platform provides new potential tools for visualizing dynamic extracellular activities and manipulating cellular behaviors using programmable in situ self‐assembling DNA molecular devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • PO 4 3−-doping and Li 3 PO 4 -coating of dual modification of LiNiO 2 are achieved. • PO 4 3− doping improves the reversibility of crystal structure. • PO 4 3− doping induces surface structural transformation of the material. • Li 3 PO 4 coating could ameliorate the interface stability. Lithium nickel oxide (LiNiO 2) cathode materials are featured with high capacity and low cost for rechargeable lithium-ion batteries but suffer from severe structure and interface instability. Bulk doping together with surface coating has been proven to be an efficient approach to improve the inner structure and interfacial stability of the LiNiO 2 cathode material. Nevertheless, the role of anion doping seems to be quite different from that of cation doping, and a deep insight will be desirable for the structure design of the LiNiO 2 cathode material. In this paper, PO 4 3−-doped and Li 3 PO 4 -coating of dual modification of LiNiO 2 are achieved via a facile approach. It is demonstrated that the PO 4 3− anions are doped into the tetrahedron vacant sites of the crystal structure, alleviating the phase transition and improving the reversibility of crystal structure. Besides, the Li 3 PO 4 coating layer ameliorates the interface stability to restrain the side reactions. Therefore, the dual modification enhances overall structural stability of the material to provide excellent performance. Moreover, the consumption of the Li residues by the formation of Li 3 PO 4 coating layer, and the enlarged interlayer spacing of the crystal structure by PO 4 3− doping can facilitate the Li+ ions diffusion, resulting in a superior rate capability. [ABSTRACT FROM AUTHOR]

• Modified xylan with good amphiphilicity was obtained under mild reaction conditions by hydroxypropylsulfonation. • HSX exhibited a satisfactory dispersion efficiency of MWCNTs in water. • The aerogels were prepared by freeze-casting technology which reveals excellent mechanical performance. • The aerogel is utilized to construct a pressure sensor, which exhibit high sensitivity (S = 2.17 kPa−1) and impressive responsiveness. Currently, aerogels are promising for wearable pressure sensors due to their superior flexibility and high sensitivity. However, uniform dispersion of conductive solid filler is a critical step in the preparation process. Herein, xylan with good amphiphilicity was obtained by hydroxypropylsulfonation under mild reaction conditions, which is accepted as a dispersant for multi-walled carbon nanotubes (MWCNTs) in water. The hydroxypropylsulfonated xylan (HSX) exhibited a satisfactory dispersion efficiency reached to 97.8 %. After standing for 20 days, there are still 76 % of MWCNTs stabilized in the dispersion. Then, the ultralight, flexible and superstable anisotropic aerogels were prepared by freeze-casting technology. The obtained aerogel reveals excellent mechanical performance, with a great compressibility (undergoing a strain of 70 %) and elasticity (91.8 % height retention after 100 cycles at a strain of 20 %). As a proof of concept, the HSX/MWCNTs aerogel is utilized to construct a pressure sensor, which exhibit high sensitivity (S = 2.17 kPa−1) and impressive responsiveness to human motions. This work demonstrates a promising flexible electronic material for wearable electronics, electronic skin, and human motion monitoring. [ABSTRACT FROM AUTHOR]