Constructing type II heterostructures represents a widely recognized strategy for enhancing charge separation and photocatalytic efficiency,but it remains challenging to fabricate homologous heterostructures based on ...
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Constructing type II heterostructures represents a widely recognized strategy for enhancing charge separation and photocatalytic efficiency,but it remains challenging to fabricate homologous heterostructures based on visible-light-responsive semiconductors,especially for popularly investigated (oxy)nitrides with low thermal ***,we synthesized a homologous heterostructure (denoted as yTON_h) based on the oxynitrides of yTaO4-xNyand yTa *** heterostructure exhibits type II band structure alignment and intimate interface achieved through a magnesium (Mg) powder-assisted nitridation *** with widely reported heterologous heterostructures,the as-obtained yTON_h homologous heterostructure could similarly exhibit enhanced charge separation as well as photocatalytic water splitting performance with respect to its counterparts(yTaO4-xNyand yTaON2).Meanwhile,detailed structural characterizations and spectroscopy analysis have been made to confirm the formation of heterostructure and promotion of spatial charge separation.
The development of dual functional material for cyclic CO2capture and hydrogenation is of great significance for converting diluted CO2into valuable fuels,but suffers from kinetic limitation and deactivation of adsorb...
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The development of dual functional material for cyclic CO2capture and hydrogenation is of great significance for converting diluted CO2into valuable fuels,but suffers from kinetic limitation and deactivation of adsorbent and ***,we engineered a series of RuNa/γ-Al2O3materials,varying the size of ruthenium from single atoms to clusters/*** coordination environment and structure sensitivity of ruthenium were quantitatively investigated at atomic *** findings reveal that the reduced Ru nanoparticles,approximately 7.1 nm in diameter with a Ru-Ru coordination number of 5.9,exhibit high methane formation activity and selectivity at 340°*** Ru-Na interfacial sites facilitate CO2migration through a deoxygenation pathway,involving carbonate dissociation,carbonyl formation,and ***-situ experiments and theoretical calculations show that stable carbonyl intermediates on metallic Ru nanoparticles facilitate heterolytic C–O scission and C–h bonding,significantly lowering the energy barrier for activating stored CO2.
Tumor suppressor p53-mediated cell cycle arrest and DNA damage repair may exert cytoprotective effects against cancer therapies, including wEE1 inhibition. Considering that p53 activation can also lead to multiple typ...
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Tumor suppressor p53-mediated cell cycle arrest and DNA damage repair may exert cytoprotective effects against cancer therapies, including wEE1 inhibition. Considering that p53 activation can also lead to multiple types of cell death, the role of this tumor suppressor in wEE1 inhibitor-based therapies remains disputed. In this study, we reported that nucleolar stress-mediated p53 activation enhanced the wEE1 inhibitor AZD1775-induced ferroptosis to suppress lung cancer growth. Our findings showed that AZD1775 promoted ferroptosis by blocking cystine uptake, an action similar to that of Erastin. Meanwhile, inhibition of wEE1 by the wEE1 inhibitors or si RNAs induced compensatory upregulation of SLC7A11, which conferred resistance to ferroptosis. Mechanistically, AZD1775 prevented the enrichment of h3K9me3, a histone marker of transcriptional repression, on the SLC7A11 promoter by repressing the expression of the histone methyltransferase SETDB1, thereby enhancing NRF2-mediated SLC7A11 transcription. This finding was also validated using the h3K9me3 inhibitor BRD4770. Remarkably, we found that the nucleolar stress-inducing agent Actinomycin D(Act. D) inhibited SLC7A11 expression by activating p53, thus augmenting AZD1775-induced ferroptosis. Moreover, the combination of AZD1775 and Act. D synergistically suppressed wild-type p53-harboring lung cancer cell growth both in vitro and in vivo. Altogether, our study demonstrates that AZD1775 promotes ferroptosis by targeting cystine uptake but also mediates the adaptive activation of SLC7A11 through the wEE1-SETDB1 cascade and NRF2-induced transcription, and inhibition of SLC7A11 by Act. D boosts the anti-tumor efficacy of AZD1775 by enhancing ferroptosis in cancers with wild-type p53.
This study investigated the microstructure and hydrogen absorption properties of a rare-earthhigh-entropy alloy(hEA),*** indicated that the yGdTbDyho alloyhad a microstructure of equiaxed grains,with the alloy eleme...
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This study investigated the microstructure and hydrogen absorption properties of a rare-earth high-entropy alloy(hEA),*** indicated that the yGdTbDyho alloy had a microstructure of equiaxed grains,with the alloy elements distributed *** hydrogen absorption,the phase structure of the hEA changed from a solid solution with an hexagonal-close-packed(hCP)structure to a high-entropy hydride with an faced-centered-cubic(FCC)structure without any secondary phase *** alloy demonstrated a maximum hydrogen storage capacity of 2.33 h/M(hydrogen atom/metal atom)at 723 K,with an enthalpy change(Δh)of-141.09 kJ·mol^(-1)and an entropy change(ΔS)of-119.14 J·mol^(-1)·K^(-1).The kinetic mechanism of hydrogen absorption was hydride nucleation and growth,with an apparent activation energy(E_(a))of 20.90 kJ·mol^(-1).without any activation,the yGdTbDyho alloy could absorb hydrogen quickly(180 s at 923 K)with nearly no incubation period *** reason for the obtained value of 2.33 h/M was that the hydrogen atoms occupied both tetrahedral and octahedral *** results demonstrate the potential application of hEAs as a high-capacity hydrogen storage material with a large h/M ratio,which can be used in the deuterium storage field.
As a potential renewable and clean energy source,the distribution and exploration prospects of natural hydrogen have garnered widespread ***,the limitations in understanding the formation mechanisms and accumulation p...
As a potential renewable and clean energy source,the distribution and exploration prospects of natural hydrogen have garnered widespread ***,the limitations in understanding the formation mechanisms and accumulation patterns of underground natural hydrogen have significantly constrained its efficient exploration and *** study reports h2content and isotopes in natural gas from deep formations in sedimentary basins through geochemical analysis of 58 conventional gas samples from the Sinian to Triassic strata in the central Sichuan *** discovered that h2content in deep natural gas in central Sichuan generally exceeds 0.1%,with a maximum of 1.6%,and hydrogen isotopes (δ2hh2) range from-850‰to-586‰.Analysis of the geological conditions,hydrogen generation mechanisms,and isotope fractionation characteristics in the study area confirms that microbial fermentation or in-situ organic matter cracking are not effective pathways for deep *** with helium content and isotope analysis of the natural gas,it is inferred that the volcanic basement in the central Sichuan area is the potential source rock for natural h2in the Sinian to Triassic ***,h2originates from the radiolysis of water and hydrothermal reactions of Fe(II) in the basement ***,a diffusion fractionation model reveals significant isotope fractionation during the migration and accumulation of deep h2into sedimentary reservoirs,which lead to anomalously light δ2hh2in deep natural gas in central *** indicates that the underground natural hydrogen accumulation is in a long-term dynamic process,with simultaneous h2accumulation and dissipation in the gas *** research not only elucidates the formation mechanism of deep h2but also provides insights for the resource potential of natural hydrogen in sedimentary basins.
Selective modification of peptides has always been a challenging issue. The selective alkylation of peptides can alter the biological activity and physical properties of molecules, and it has gained significant resear...
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Selective modification of peptides has always been a challenging issue. The selective alkylation of peptides can alter the biological activity and physical properties of molecules, and it has gained significant research interest. we herein disclose an intriguing gold-catalyzed alkylation of peptides using bench-stable unactivated alkyl bromides under photoredox catalysis. A wide range of structurally diverse primary, secondary and tertiary alkyl bromides serve as effective coupling partners to precisely connect with the α-C(sp3)–h in glycine residue of peptides. This protocol demonstrates an exceptionally broad scope for alkyl halides and excellent tolerance for a wide range of useful functional groups. A series of relay transformations to construct cyclic peptides, to proceed click reaction and to realize peptide fluorescence labeling further enhance its synthetic practicality. In addition, mechanistic studies and density functional theory(DFT) calculations reveal an inner-sphere and subsequent outersphere single electron transfer(SET) mechanism.
Elias,et al.(2016)conjectured that the Kazhdan-Lusztig polynomial of any matroid is *** by a computer proof of Moll’s log-concavity conjecture given by Kauers and Paule,the authors use a computer algebra system to pr...
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Elias,et al.(2016)conjectured that the Kazhdan-Lusztig polynomial of any matroid is *** by a computer proof of Moll’s log-concavity conjecture given by Kauers and Paule,the authors use a computer algebra system to prove the conjecture for arbitrary uniform matroids.
On the basis of the framework of systematic science of alloys (SSA), the basic information such as states, volumes, and potential energies of characteristic atoms in hcp Ti-Al system have been determined. The averag...
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On the basis of the framework of systematic science of alloys (SSA), the basic information such as states, volumes, and potential energies of characteristic atoms in hcp Ti-Al system have been determined. The average atomic state of the hcp Ti3Al compound consisting of ψ4^Ti and ψ0^Al atoms is 0.75[Ar] (3dn)^0.573 (3dc)^2.1685 (4sc)^0.972 (4sf)^0.3093 + 0.25[Ne] (3sc)^1.32 (3pc)^1.19 (3sf + 3pf)^0.49. The brittleness of the ordered hcp Ti3Al compound has been discussed considering the fundamental factors, which are atomic states, bond networks, potential energy wave planes, and the ratio xTi/xAl. The existence of more pc and more dc directional electrons in the hcp Ti3Al compound lead to considerable brittleness; From bond networks and potential energy wave planes, the hcp Ti3Al compound has poorer ductility than the pure hcp Ti metal and the pure fcc Al metal; The Al-rich hcp Ti3Al ordered type alloys have poorer ductility than the Ti-rich hcp Ti3Al ordered type alloys.
Pipes are often used to transport multiphase flows in many engineering *** total fluid flow density inside a pipe may varywith time and *** this paper,a simply supported pipe conveying a variable density flow is mode...
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Pipes are often used to transport multiphase flows in many engineering *** total fluid flow density inside a pipe may vary with time and *** this paper,a simply supported pipe conveying a variable density flow is modeled theoretically,and its stability and nonlinear vibrations are investigated in *** variation of the flow density is simulated using a mathematical *** equation governing the vibration of the pipe is derived according to Euler-Bernoulli beam *** the internal flow density varies with time,the pipe is excited *** stability of the pipe is determined by Floquet *** simple parametric and combination resonances are *** a higher mass ratio(mean flow mass/pipe structural mass),higher flow velocity,or smaller end axial tension,the pipe becomes unstable more easily due to wider parametric resonance *** the subcritical flow velocity regime,the vibrations of the pipe are periodic and quasiperiodic for simple and combination resonances,***,in the supercritical regime,the vibrations of the pipe exhibit much richer dynamics including periodic,multiperiodic,quasiperiodic,and chaotic behaviors.
The mathematic calculation on two--bodywear of austenitic manganese steel has been performed by means of the elastic contact theory,stress interferometer and *** distribution in contacted area was calculated and the ...
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The mathematic calculation on two--body wear of austenitic manganese steel has been performed by means of the elastic contact theory,stress interferometer and *** distribution in contacted area was calculated and the mechanism on two--body wear has been investigated through numerical *** show that two--body wear is mainly plowing wear the cracks of abrasive dust originates from the region between 0.2αand 0.5α(αis radius of contacted round).Driving force to make crack extension along y axis is T_(yzmax)and extension direction is 45°with *** forces to make crack extension along x axis is alternativeσ_x and T_(yzmax),the direction of crack extension is 37°with horizon.
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