Up-and-coming high-temperature materials,refractory high entropy alloys,are suffering from lower oxidation resistance,restricting their applications in the aerospace field.In this study,two novel treatments of Al-depo...Up-and-coming high-temperature materials,refractory high entropy alloys,are suffering from lower oxidation resistance,restricting their applications in the aerospace field.In this study,two novel treatments of Al-deposited and remelted were developed to refine the microstructure and enhance the oxidation resistance of refractory high entropy alloy using electron beam freeform fabrication(EBF3).Finer and short-range ordering structures were observed in the remelted sample,whereas the Al-deposited sample showcased the formation of silicide and intermetallic phases.High-temperature cyclic and isothermal oxidation tests at 1000℃ were carried out.The total weight gain after 60 h of cyclic oxidation decreased by 17.49%and 30.46%for the remelted and deposited samples,respectively,compared to the as-cast state.Oxidation kinetics reveal an evident lower mass gain and oxidation rate in the treated samples.A multilayer oxide consisting of TiO_(2)+Al_(2)O_(3)+SiO_(2)+AlNbO_(4) was studied for its excellent oxidation resistance.The oxidation behavior of rutile,corundum and other oxides was analyzed using first principles calculations and chemical defect analysis.Overall,this research,which introduces novel treatments,offers promising insights for enhancing the inherent oxidation resistance of refractory high entropy alloys.展开更多
Many strategies have been proposed to produce arenes from lignin as liquid fuel additives.However,the development of these methods is limited by the low yield of products,low atom utilization,and inefficient lignin de...Many strategies have been proposed to produce arenes from lignin as liquid fuel additives.However,the development of these methods is limited by the low yield of products,low atom utilization,and inefficient lignin depolymerization.Herein,we develop an energy-efficient synthetic method for the production of high-carbon-number arenes from sustainable lignin with a total yield of 23.1 wt%.Particularly,high carbon number arenes are obtained by fully utilizing the formaldehyde stabilizing additive and the methoxy group in lignin.The process begins with the reductive depolymerization of formaldehyde-stabilized lignin,followed by transmethylation between lignin monomers over Au/Nb_(2)O_(5) catalyst,and the Ru/Nb2O5-catalyzed hydrodeoxygenation.This work demonstrates the potential of value-added arenes production directly from lignin.展开更多
As one of the most important industrially viable methods for carbon dioxide(CO_(2))utilization,methanol synthesis serves as a platform for production of green fuels and commodity chemicals.For sustainable methanol syn...As one of the most important industrially viable methods for carbon dioxide(CO_(2))utilization,methanol synthesis serves as a platform for production of green fuels and commodity chemicals.For sustainable methanol synthesis,In_(2)O_(3)is an ideal catalyst and has garnered significant attention.Herein,cubic In_(2)O_(3)nanoparticles were prepared via the precipitation method and evaluated for CO_(2)hydrogenation to produce methanol.During the initial 10 h of reaction,CO_(2)conversion gradually increased,accompanied by a slow decrease of methanol selectivity,and the reaction reached equilibrium after 10-20 h on stream.This activation and induction stage may be attributed to the sintering of In_(2)O_(3)nanoparticles and the creation of more oxygen vacancies on In_(2)O_(3)surfaces.Further experimental studies demonstrate that hydrogen induction created additional oxygen vacancies during the catalyst activation stage,enhancing the performance of In_(2)O_(3)catalyst for CO_(2)hydrogenation.Density functional theory calculations and microkinetic simulations further demonstrated that surfaces with higher oxygen vacancy coverages or hydroxylated surfaces formed during this induction period can enhance the reaction rate and increase the CO_(2)conversion.However,they predominantly promote the formation of CO instead of methanol,leading to reduced methanol selectivity.These predictions align well with the above-mentioned experimental observations.Our work thus provides an in-depth analysis of the induction stage of the CO_(2)hydrogenation process on In_(2)O_(3)nano-catalyst,and offers valuable insights for significantly improving the CO_(2)reactivity of In_(2)O_(3)-based catalysts while maintaining long-term stability.展开更多
The field-reversed configuration(FRC)plasma thruster driven by rotating magnetic field(RMF),abbreviated as the RMF-FRC thruster,is a new type of electric propulsion technology that is expected to accelerate the deep s...The field-reversed configuration(FRC)plasma thruster driven by rotating magnetic field(RMF),abbreviated as the RMF-FRC thruster,is a new type of electric propulsion technology that is expected to accelerate the deep space exploration.An experimental prototype,including diagnostic devices,was designed and constructed based on the principles of the RMF-FRC thruster,with an RMF frequency of 210 kHz and a maximum peak current of 2 kA.Under the rated operating conditions,the initial plasma density was measured to be 5×10^(17)m^(-3),and increased to 2.2×10^(19)m^(-3)after the action of RMF.The coupling efficiency of RMF was about 53%,and the plasma current reached 1.9 kA.The axial magnetic field changed in reverse by 155 Gauss,successfully reversing the bias magnetic field of 60 Gauss,which verifies the formation of FRC plasma.After optimization research,it was found that when the bias magnetic field is 100 Gauss,the axial magnetic field reverse variation caused by FRC is the highest at 164 Gauss.The experimental results are discussed and strategies are proposed to improve the performance of the prototype.展开更多
Amborella trichopoda(Amborellaceae;hereafter simply Amborella)(Fig.1A)is a shrub endemic to New Caledonia in the Southwest Pacific that represents the sole sister species of all other extant angiosperms(Qiu et al.,199...Amborella trichopoda(Amborellaceae;hereafter simply Amborella)(Fig.1A)is a shrub endemic to New Caledonia in the Southwest Pacific that represents the sole sister species of all other extant angiosperms(Qiu et al.,1999;One Thousand Plant Transcriptomes Initiative,2019).Due to its unique phylogenetic status,it holds tremendous interest for botanists.The nuclear and mitochondrial genomes of Amborella were first published in 2013,providing valuable resources for studies on genome and gene family evolution,phylogenomics,and flower development,despite the fact that the assembly is heavily fragmented(Amborella Genome Project,2013;Rice et al.,2013).In 2024,a haplotype-resolved Amborella genome assembly was published,showing significant improvement in quality and completeness(Carey et al.,2024).展开更多
This study provides a comprehensive summary of the current development status of the potato industry in Liangshan Prefecture,and analyzes the primary factors that hinder the advancement of this industry,including a lo...This study provides a comprehensive summary of the current development status of the potato industry in Liangshan Prefecture,and analyzes the primary factors that hinder the advancement of this industry,including a low degree of scale,a limited popularization rate of high-quality seeds,insufficient mechanization,a low level of commercialization,inadequate technological support,minimal integration between the secondary and tertiary industries,and an ineffective mechanism for connecting and benefiting farmers.Furthermore,it presents a problem-oriented approach that is grounded in the current climatic,resource,water,and soil conditions of Liangshan Prefecture,and proposes several pathways to promote the high-quality development of the potato industry.The strategies include:expanding coverage and increasing production volume as foundational steps to ensure food security;enhancing quality and efficiency as key drivers to stimulate agricultural advancement through scientific and technological innovation;focusing on the integration of the three industries to achieve industrial revitalization;implementing risk management measures as a preventive strategy to ensure industrial stability;establishing incentive policies to foster production enthusiasm;and ultimately assisting farmers in increasing their income to achieve the overarching goal of improving the livelihoods of the population.展开更多
Five new flavan-4-ol glycosides jixueqiosides A-E(1-5)and two new flavan glycosides jixueqiosides F and G(6 and 7),along with twelve known flavan-4-ol glycosides(8-19),were isolated from the roots of Pronephrium penan...Five new flavan-4-ol glycosides jixueqiosides A-E(1-5)and two new flavan glycosides jixueqiosides F and G(6 and 7),along with twelve known flavan-4-ol glycosides(8-19),were isolated from the roots of Pronephrium penangianum.Comprehensive spectral analyses,X-ray single-crystal diffraction,and theoretical electronic circular dichroism(ECD)calculations established structures and absolute configurations.A single crystal structure of flavan-4-ol glycoside(14)was reported for the first time,while the characteristic ECD and NMR data for all isolated flavan-4-ol glycosides(1-5,8-19)were analyzed,establishing a set of empirical rules.Activity screening of these isolates showed that 8 and 9 could inhibit the proliferation of MDA-MB-231 and MCF-7 cells with IC50 values of 7.93±2.85μmol·L^(-1)and 5.87±1.58μmol·L^(-1)(MDA-MB-231),and 2.21±1.38μmol·L^(-1)and 3.52±1.55μmol·L^(-1)(MCF-7),respectively.Western blotting and flow cytometry analyses demonstrated that 8 and 9 dose-dependently induced apoptosis in MDA-MB-231 cells by up-regulating BAX,activating caspase-3 and down-regulating BCL-2.Additionally,compound 8 affected autophagy-related proteins,increasing the ratio of LC3-II/LC3-I and Beclin-1 levels to inhibit MDA-MB-231 cell proliferation.Moreover,anti-inflammatory studies indicated that 2,3,7,13,14,and 18 moderately inhibited tumor necrosis factor-α(TNF-α),interleukin-6(IL-6),and nitric oxide(NO)release.展开更多
High molecular weight polycyclic aromatic hydrocarbons(HMW-PAHs)pose significant environmental challenges due to their complex structures and persistent toxicity,and are difficult to be degraded by bacteria.Fungi,howe...High molecular weight polycyclic aromatic hydrocarbons(HMW-PAHs)pose significant environmental challenges due to their complex structures and persistent toxicity,and are difficult to be degraded by bacteria.Fungi,however,possess the ability to overcome these challenges,primarily through various enzymes with broad substrate specificity,including cytochrome P450(CYP450),laccase,manganese peroxidase,lignin peroxidase.As a result,the development of efficient fungal strains capable of degrading HMW-PAHs is essential for advancing bioremediation strategies.In this study,Aspergillus fumigatus Z5 was isolated from a contaminated site and demonstrated a remarkable ability to degrade the highly recalcitrant benzo[a]pyrene,achieving a degradation rate of 75.43%.Transcriptomic analysis revealed significant upregulation of 34 CYP450 genes.Among these genes,CYP3A4(gene 8840)showed strong binding affinity for benzo[a]pyrene,as confirmed by molecular docking studies,indicating its key role in the biodegradable process.Furthermore,the metabolic network analysis showed that the electron transfer required for CYP450-mediated oxidative reactions enhanced mitochondrial oxidative phosphorylation and subsequently energy metabolism in A.fumigatus Z5.This metabolic coordination likely facilitates the complete degradation of benzo[a]pyrene.Our study illuminates the fundamental roles of CYP450 from A.fumigatus Z5 in benzo[a]pyrene degradation and provides novel insight into designing and implementing enhanced bioremediation strategies.展开更多
One-dimensional nanomaterials with hollow structures could provide large space for ion storage and charge accumulation.Herein,TiO_(2)/MoSe_(2)-Carbon nanotube composite(NT)materials were designed and fabricated by the...One-dimensional nanomaterials with hollow structures could provide large space for ion storage and charge accumulation.Herein,TiO_(2)/MoSe_(2)-Carbon nanotube composite(NT)materials were designed and fabricated by the template method and the chelation coordination reaction.The stability and conductivity were improved by the presence of titanium and hollow tubular-architecture carbon in the whole structure.As a result,the as-prepared TiO_(2)/MoSe_(2)-Carbon hybrid achieved a high-rate performance of 760.0 mAh·g^(−1) at a current density of 0.1 A·g^(−1),while still obtaining stability after 300 charge/discharge cycles.The enhancement of the lithium storage capacity mainly contributed to the acceleration of the electron conductivity and the storage kinetics.Moreover,the hollow structure reduced the volume strain and stress caused by the rapid insertion and removal of lithium ions,which ensured the favorable stability of lithium storage.The experiment shows that the kinetic of the TiO_(2)/MoSe_(2)-carbon hybrid during the lithium storage process is dominated by the pseudocapacitance mechanism.This work provides a new idea and scheme for the design and preparation of hierarchical nanotube composite electrode materials.展开更多
Oxidative coupling of methane(OCM)is a catalytic partial oxidation process that directly converts methane into C_(2) products.For this high temperature reaction,understanding the radical behavior through experimental ...Oxidative coupling of methane(OCM)is a catalytic partial oxidation process that directly converts methane into C_(2) products.For this high temperature reaction,understanding the radical behavior through experimental investigation is important in correlating the catalytic activity and the products.In this work,a spatial resolution online mass spectrometry(MS)system was developed and applied to a Mn-Na_(2)WO_(4)/SiO_(2) catalyzed OCM system.In addition to the residue gas analysis,the system obtained the distribution information of the reactants and products in the reactor.At various setting temperatures,all species online MS signals were collected at different positions,mapping the reaction activity covering parameters including temperature,time and space.The distribution behavior of the catalytic activity,selectivity,and apparent activation energy were kinetically analyzed.Selectivity and additional carbon balance analysis strongly supported the radical coupling model of OCM and indicated that after the catalytic bed layer,there is a significant length in the reactor(>2 mm)filled with radicals.Based on the result,a designed new method by tuning the temperature field in the reactor was found effectively to improve the catalytic activity,especially the C_(2) yield from 702 to 773℃.展开更多
Surface irregularities,such as hills and ridges,can significantly amplify ground motion caused by earthquakes.Therefore,in this study,we propose an analytical solution model to investigate the interaction between an a...Surface irregularities,such as hills and ridges,can significantly amplify ground motion caused by earthquakes.Therefore,in this study,we propose an analytical solution model to investigate the interaction between an asymmetric triangular hill on Earth and SH waves.Firstly,based on the development of wave functions and regional matching techniques,we introduce a semi-circular artificial auxiliary boundary,dividing the solution model into a semi-infinite body containing a semi-circular depression and an asymmetric fan-shaped region.Secondly,we derive the domain function form applicable to solving asymmetric problems.Utilizing the theory of complex variables,we establish a well-posed matrix for solving domain functions within the same coordinate system.Numerical results demonstrate that the scattering of SH waves by a protuberance is jointly influenced by the geometric parameters of the hill and the angle of incidence.Additionally,the frequency of the incident wave also has a certain degree of impact on the displacement amplitude.This study elucidates the scattering mechanism of SH waves by complex boundaries,providing a theoretical reference for building site selection and seismic design.In practical problems,the asymmetric assumption is more applicable than the symmetry assumption.展开更多
As the plasma current power in tokamak devices increases,a significant number of stray magnetic fields are generated around the equipment.These stray magnetic fields can disrupt the operation of electronic power devic...As the plasma current power in tokamak devices increases,a significant number of stray magnetic fields are generated around the equipment.These stray magnetic fields can disrupt the operation of electronic power devices,particularly transformers in switched-mode power supplies.Testing flyback converters with transformers under strong background magnetic fields highlights electromagnetic compatibility(EMC)issues for such switched-mode power supplies.This study utilizes finite element analysis software to simulate the electromagnetic environment of switched-mode power supply transformers and investigates the impact of variations in different magnetic field parameters on the performance of switched-mode power supplies under strong stray magnetic fields.The findings indicate that EMC issues are associated with transformer core saturation and can be alleviated through appropriate configurations of the core size,air gap,fillet radius,and installation direction.This study offers novel solutions for addressing EMC issues in high magnetic field environments.展开更多
BACKGROUND Omental torsion(OT)is a rare cause of acute abdomen,it can be difficult to diagnose preoperatively and is frequently misdiagnosed.Computed tomography(CT)is the primary imaging modality for OT.It typically s...BACKGROUND Omental torsion(OT)is a rare cause of acute abdomen,it can be difficult to diagnose preoperatively and is frequently misdiagnosed.Computed tomography(CT)is the primary imaging modality for OT.It typically shows the swirl sign.contrast-enhanced CT can better visualize the central vascular structure of the mass,thus improving the diagnostic accuracy for OT.Surgical resection is the mainstay of treatment for OT.Laparoscopy allows direct visualization of the primary torsion site and comprehensive abdominal exploration,thereby decreasing misdiagnoses.It is a safe and reliable approach for OT treatment,which offers the advantages of minimal trauma,mild postoperative pain,and rapid recovery for stylistic precision.CASE SUMMARY A 48-year-old man was admitted to our hospital due to lower right abdominal pain for the preceding 70 hours.Physical examination revealed lower right abdominal muscle strain,tenderness,and rebound pain,but no mass was palpable.Contrast-enhanced CT revealed a thickened,blurred omentum with swirling changes in the right abdomen.Laparoscopic exploration and omentectomy were performed in the emergency setting.The procedure revealed 50 mL of dark-red bloody ascites in the pelvis and twisting of the right omentum along its longitudinal axis,with a 10 cm×8 cm purple-black necrosis at the distal end.Postsurgical pathology revealed omental hemorrhage,degeneration,and necrosis.The patient had an uneventful recovery and was discharged on the fourth postoperative day.During the subsequent nine-month follow-up,he remained asymptomatic.CONCLUSION OT is a rare disease that lacks specific clinical manifestations.Abdominal contrast-enhanced CT plays a crucial role in diagnosing OT,and laparoscopic surgery is a safe and effective diagnostic and therapeutic approach.展开更多
Over the past two decades,our understanding of Lauraceae,a large family of woody plants,has undergone significant advances in phylogeny,taxonomy,and biogeography.Molecular systematic studies have elucidated the basic ...Over the past two decades,our understanding of Lauraceae,a large family of woody plants,has undergone significant advances in phylogeny,taxonomy,and biogeography.Molecular systematic studies have elucidated the basic relationships within the family with plastid phylogenomic analyses providing robust support for deep-level relationships between Lauraceae lineages,leading to the recognition of nine tribes:Hypodaphnideae,Cryptocaryeae,Cassytheae,Neocinnamomeae,Caryodaphnopsideae,Mezilaureae,Perseeae,Laureae,and Cinnamomeae,with Mezilaureae validated here.Nuclear genomes and comparative genomics studies have also clarified aspects of the family’s evolutionary history and metabolic diversity.Taxonomic studies have focused mainly on the most diverse regions,e.g.,tropical Asia,tropical America,and Africa(Madagascar),with six new genera described and five reinstated since the last major overview of the family.The extensive fossil record suggests that Lauraceae diversified globally during the Late Cretaceous and Early Cenozoic.Biogeographic studies indicate that different lineages of the family are sorted into Gondwanan and Laurasian lineages,with patterns resulting from the disruption of boreotropical flora and multiple long-distance dispersal events.Phylogeographic studies,predominantly from East Asia,have shown patterns of in situ survival and demographic stability or expansion during the Quaternary.Nevertheless,many systematic relationships within the family remain unresolved and further research is needed into the complex biogeographic history and ecological roles of Lauraceae.A multifaceted approach integrating genomic studies,field work,morphological and ecological investigations is therefore needed to understand the evolution and diversity of this ecologically and economically significant plant family.展开更多
Melon is a globally cultivated horticultural crop with a predominantly hybrid commercial seed market in China.Seedling morphology,particularly hypocotyl color,is a valuable trait for rapid F1 hybrid seed purity assess...Melon is a globally cultivated horticultural crop with a predominantly hybrid commercial seed market in China.Seedling morphology,particularly hypocotyl color,is a valuable trait for rapid F1 hybrid seed purity assessment.While green hypocotyls are common,white hypocotyls are rare in melon germplasm.This study identified a mutant with white hypocotyl but green leaves from the heavy ion beam mutant library.Genetic analysis revealed that a single recessive gene controlled the white hypocotyl,designated CmGhc1.A single-base deletion in the fifth exon of CmGhc1 led to a truncated CmGhc1 lacking the HTH-MYB DNA binding domain,likely affecting its transcriptional activity.CmGhc1 was localized in the nucleus,and yeast two-hybrid analysis and a dual-LUC assay demonstrated it as a transcription repressor.Furthermore,a KASP marker(hc1)was developed and verified as a functional marker for breeding white hypocotyl germplasms in melon.RNA-seq data revealed that CmGhc1 significantly affected the transcription of genes related to chlorophyll metabolism and photosynthesis in hypocotyl.In summary,these findings contribute to our understanding of chloroplast biogenesis and provide a valuable tool for melon breeding.展开更多
Nanostructured materials with small particle sizes have been widely used in resistive gas sensors due to their high specific surface area and surface activity.However,phenomena including agglomeration,growth and struc...Nanostructured materials with small particle sizes have been widely used in resistive gas sensors due to their high specific surface area and surface activity.However,phenomena including agglomeration,growth and structural damage of nanostructures are almost inevitable during the processes of device fabrication or sensing tests,which makes it difficult to exert their expected activity.To address this issue,rare earth metal oxide CeO_(2)was chosen as the model material to explore confined nanostructures in resistive gas sensors.The experiment successfully achieves the preparation of confined CeO_(2)nanoparticles film using a pulsed laser deposition combined with rapid annealing technology.It is found that the confined CeO_(2)nanoparticles film enables the efficient detection of volatile organic compound triethylamine,demonstrating a significant response of 20(Ra/Rg)towards 100 ppm triethylamine,a fast response of 2 s,excellent stability and selectivity.By in-situ confinement in porous carbon matrix,dispersion and fixation of CeO_(2)nanoparticles can be achieved,thereby fully utilizing their high surface activity.In addition,the porous carbon matrix can serve as a transport pathway for the target gas molecules and electrons,enabling efficient gas-solid reactions and effective collection of gas sensing signals.More importantly,the confined CeO_(2)nanoparticles film was grown in-situ on commercial alumina flats gas sensing substrate,which can be directly used as sensing layer for gas sensors.Based on first-principles calculations,the triethylamine sensing mechanism of the confined CeO_(2)nanoparticles film was systematically analyzed at the atomic and electronic scale.This study offers new insights into enhancing the gas sensing performance of resistive gas sensors through confined nanostructures design.展开更多
A potential orthorhombic phase of Ta_(2)O_(5),designated as Y-Ta_(2)O_(5),is predicted under high-pressure conditions using density functional theory(DFT)combined with structural search algorithms.This phase,containin...A potential orthorhombic phase of Ta_(2)O_(5),designated as Y-Ta_(2)O_(5),is predicted under high-pressure conditions using density functional theory(DFT)combined with structural search algorithms.This phase,containing four formula units per unit cell(Z=4),exhibits the highest Ta-O coordination numbers reported to date.Y-Ta_(2)O_(5)is identified as the most energetically stable form of Ta_(2)O_(5)within the pressure range of approximately 70 GPa to at least 200 GPa.Both standard DFT-GGA and higher-accuracy GW calculations indicate that Y-Ta_(2)O_(5)is a wide-bandgap semiconductor with a direct bandgap.Furthermore,nuclear quantum effects(NQEs)introduce nontrivial corrections to external pressure at fixed volumes,underscoring their significance in high-pressure phase stability analyses.展开更多
The oxidation of lignin model compounds to esters via C-C bond cleavage has attracted considerable attention,as esters could be used as important polymer precursors and pharmaceutical intermediates.However,most studie...The oxidation of lignin model compounds to esters via C-C bond cleavage has attracted considerable attention,as esters could be used as important polymer precursors and pharmaceutical intermediates.However,most studies focus on designing homogeneous or noble metal catalysts and conducting the reactions under basic conditions.Here,we report an efficient process for the C-C bond cleavage of lignin model compounds and selectively producing esters over different shaped CeO_(2)(i.e.,nanospheres(S),nanorods(R),nanoparticles(P),and nanocubes(C))under base-free conditions.Specifically,the yield of methyl anisate from the aerobic oxidation of l-(4-methoxyphenyl)ethanol reaches 77.6%over CeO_(2)-S in one hour(91%in 9 h),exhibiting higher performance compared to other evaluated CeO_(2)catalysts(6.4%-40.2%).Extensivecharacterizations and experimental investigations reveal that the density of weak base sites and oxygen vacancies on the CeO_(2)surface is positively correlated with the yield of methyl esters.Furthermore,the reaction pathway is investigated,which confirms that 1-(4-methoxyphenyl)ethanol first undergoes two reactions(i.e.,etherification and dehydrogenation)to produce intermediates of1-methoxy-4-(1-methoxy-ethyl)-benzene and 1-(4-methoxyphenyl)ethanone,respectively,followed by a series of functional group transformations to generate the targeted methyl anisate ultimately.展开更多
Magnetically responsive microstructured functional surface(MRMFS),capable of dynamically and reversibly switching the surface topography under magnetic actuation,provides a wireless,noninvasive,and instantaneous way t...Magnetically responsive microstructured functional surface(MRMFS),capable of dynamically and reversibly switching the surface topography under magnetic actuation,provides a wireless,noninvasive,and instantaneous way to accurately control the microscale engineered surface.In the last decade,many studies have been conducted to design and optimize MRMFSs for diverse applications,and significant progress has been accomplished.This review comprehensively presents recent advancements and the potential prospects in MRMFSs.We first classify MRMFSs into one-dimensional linear array MRMFSs,two-dimensional planar array MRMFSs,and dynamic self-assembly MRMFSs based on their morphology.Subsequently,an overview of three deformation mechanisms,including magnetically actuated bending deformation,magnetically driven rotational deformation,and magnetically induced self-assembly deformation,are provided.Four main fabrication strategies employed to create MRMFSs are summarized,including replica molding,magnetization-induced self-assembly,laser cutting,and ferrofluid-infused method.Furthermore,the applications of MRMFS in droplet manipulation,solid transport,information encryption,light manipulation,triboelectric nanogenerators,and soft robotics are presented.Finally,the challenges that limit the practical applications of MRMFSs are discussed,and the future development of MRMFSs is proposed.展开更多
Lily-Ziziphi Spinosae Semen decoction(LZ)is known for its blood nourishing,mind calming,body sedation,and sleep promoting effects in traditional Chinese medicine.However,its material basis and underlying mechanisms ha...Lily-Ziziphi Spinosae Semen decoction(LZ)is known for its blood nourishing,mind calming,body sedation,and sleep promoting effects in traditional Chinese medicine.However,its material basis and underlying mechanisms have not yet been clearly defined.This study applies liquid chromatography-mass spectrometry,network pharmacology,and animal studies to reveal the material basis and sleep-improving mechanisms of LZ.The mixed decoction(LZ-ME)and single decoction(LZ-SE)were prepared to study their chemical components.Network pharmacology was used to predict the sleep-improving targets and signaling pathways of LZ.ICR mice were intragastrically administered saline(NC),melatonin(positive control group,0.50 mg/kg),low(12.90 g/kg),medium(25.70 g/kg),and high(38.60 g/kg)dose of LZ-ME and LZ-SH for 30 days.The results showed that LZ-ME could prolong the sleep duration and shorten the sleep latency in sodium barbiturate induced mice model.The results of chemical composition showed that total polysaccharides,total flavonoids,total saponins,and total alkaloids in LZ-ME were significantly higher than those in LZ-SE(177.20%,82.34%,30.58%,and 11.66%,respectively).A total of 58 chemical components were identified by ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UPLC-QTOF-MS),and 8 representative difference components of LZ-ME and LZ-SE were found.LZ-ME significantly increased tumor necrosis factor-α(TNF-α)in mice serum and neurotransmitterγ-aminobutyric acid(GABA)levels in mice hippocampus,decreased dopamine(DA)and glutamate(Glu)levels in mice hippocampus(P<0.05).Furthermore,LZ-ME up-regulated the abundance of the beneficial bacteria Lactobacillus and Eubacterium_R,down-regulated the abundance of the harmful bacteria Lachnospiraceae etc.The polysaccharides,flavonoids(spinosin and 6‴-feruloylspinosin)and saponins(jujuboside A and jujuboside B)were the main material bases for the sleep-promoting effects of LZ.These compounds may directly enhance levels of the GABA,reduced levels of Glu and DA and improve TNF-αlevels.And they also may indirectly regulate GABA levels by influencing the relative abundance of Lactobacillus and Eubacterium.展开更多
基金supported by the National Key Research and Development Program of China(Grant No.2022YFF0609000)National Natural Science Foundation of China(Grant Nos.52171034 and 52101037)Postdoctoral Fellowship Program of CPSFara(No.GZB20230944).
文摘Up-and-coming high-temperature materials,refractory high entropy alloys,are suffering from lower oxidation resistance,restricting their applications in the aerospace field.In this study,two novel treatments of Al-deposited and remelted were developed to refine the microstructure and enhance the oxidation resistance of refractory high entropy alloy using electron beam freeform fabrication(EBF3).Finer and short-range ordering structures were observed in the remelted sample,whereas the Al-deposited sample showcased the formation of silicide and intermetallic phases.High-temperature cyclic and isothermal oxidation tests at 1000℃ were carried out.The total weight gain after 60 h of cyclic oxidation decreased by 17.49%and 30.46%for the remelted and deposited samples,respectively,compared to the as-cast state.Oxidation kinetics reveal an evident lower mass gain and oxidation rate in the treated samples.A multilayer oxide consisting of TiO_(2)+Al_(2)O_(3)+SiO_(2)+AlNbO_(4) was studied for its excellent oxidation resistance.The oxidation behavior of rutile,corundum and other oxides was analyzed using first principles calculations and chemical defect analysis.Overall,this research,which introduces novel treatments,offers promising insights for enhancing the inherent oxidation resistance of refractory high entropy alloys.
文摘Many strategies have been proposed to produce arenes from lignin as liquid fuel additives.However,the development of these methods is limited by the low yield of products,low atom utilization,and inefficient lignin depolymerization.Herein,we develop an energy-efficient synthetic method for the production of high-carbon-number arenes from sustainable lignin with a total yield of 23.1 wt%.Particularly,high carbon number arenes are obtained by fully utilizing the formaldehyde stabilizing additive and the methoxy group in lignin.The process begins with the reductive depolymerization of formaldehyde-stabilized lignin,followed by transmethylation between lignin monomers over Au/Nb_(2)O_(5) catalyst,and the Ru/Nb2O5-catalyzed hydrodeoxygenation.This work demonstrates the potential of value-added arenes production directly from lignin.
文摘As one of the most important industrially viable methods for carbon dioxide(CO_(2))utilization,methanol synthesis serves as a platform for production of green fuels and commodity chemicals.For sustainable methanol synthesis,In_(2)O_(3)is an ideal catalyst and has garnered significant attention.Herein,cubic In_(2)O_(3)nanoparticles were prepared via the precipitation method and evaluated for CO_(2)hydrogenation to produce methanol.During the initial 10 h of reaction,CO_(2)conversion gradually increased,accompanied by a slow decrease of methanol selectivity,and the reaction reached equilibrium after 10-20 h on stream.This activation and induction stage may be attributed to the sintering of In_(2)O_(3)nanoparticles and the creation of more oxygen vacancies on In_(2)O_(3)surfaces.Further experimental studies demonstrate that hydrogen induction created additional oxygen vacancies during the catalyst activation stage,enhancing the performance of In_(2)O_(3)catalyst for CO_(2)hydrogenation.Density functional theory calculations and microkinetic simulations further demonstrated that surfaces with higher oxygen vacancy coverages or hydroxylated surfaces formed during this induction period can enhance the reaction rate and increase the CO_(2)conversion.However,they predominantly promote the formation of CO instead of methanol,leading to reduced methanol selectivity.These predictions align well with the above-mentioned experimental observations.Our work thus provides an in-depth analysis of the induction stage of the CO_(2)hydrogenation process on In_(2)O_(3)nano-catalyst,and offers valuable insights for significantly improving the CO_(2)reactivity of In_(2)O_(3)-based catalysts while maintaining long-term stability.
基金supported by National Natural Science Foundation of China (NSFC) (Nos.62201217 and 51821005)。
文摘The field-reversed configuration(FRC)plasma thruster driven by rotating magnetic field(RMF),abbreviated as the RMF-FRC thruster,is a new type of electric propulsion technology that is expected to accelerate the deep space exploration.An experimental prototype,including diagnostic devices,was designed and constructed based on the principles of the RMF-FRC thruster,with an RMF frequency of 210 kHz and a maximum peak current of 2 kA.Under the rated operating conditions,the initial plasma density was measured to be 5×10^(17)m^(-3),and increased to 2.2×10^(19)m^(-3)after the action of RMF.The coupling efficiency of RMF was about 53%,and the plasma current reached 1.9 kA.The axial magnetic field changed in reverse by 155 Gauss,successfully reversing the bias magnetic field of 60 Gauss,which verifies the formation of FRC plasma.After optimization research,it was found that when the bias magnetic field is 100 Gauss,the axial magnetic field reverse variation caused by FRC is the highest at 164 Gauss.The experimental results are discussed and strategies are proposed to improve the performance of the prototype.
基金supported by the National Natural Science Foundation of China(32270217,31970205,31770211)Metasequoia funding of Nanjing Forestry University to YY。
文摘Amborella trichopoda(Amborellaceae;hereafter simply Amborella)(Fig.1A)is a shrub endemic to New Caledonia in the Southwest Pacific that represents the sole sister species of all other extant angiosperms(Qiu et al.,1999;One Thousand Plant Transcriptomes Initiative,2019).Due to its unique phylogenetic status,it holds tremendous interest for botanists.The nuclear and mitochondrial genomes of Amborella were first published in 2013,providing valuable resources for studies on genome and gene family evolution,phylogenomics,and flower development,despite the fact that the assembly is heavily fragmented(Amborella Genome Project,2013;Rice et al.,2013).In 2024,a haplotype-resolved Amborella genome assembly was published,showing significant improvement in quality and completeness(Carey et al.,2024).
基金Supported by Special Fund for the Construction of China Agricultural Industry Research System(CARS-09-ES22).
文摘This study provides a comprehensive summary of the current development status of the potato industry in Liangshan Prefecture,and analyzes the primary factors that hinder the advancement of this industry,including a low degree of scale,a limited popularization rate of high-quality seeds,insufficient mechanization,a low level of commercialization,inadequate technological support,minimal integration between the secondary and tertiary industries,and an ineffective mechanism for connecting and benefiting farmers.Furthermore,it presents a problem-oriented approach that is grounded in the current climatic,resource,water,and soil conditions of Liangshan Prefecture,and proposes several pathways to promote the high-quality development of the potato industry.The strategies include:expanding coverage and increasing production volume as foundational steps to ensure food security;enhancing quality and efficiency as key drivers to stimulate agricultural advancement through scientific and technological innovation;focusing on the integration of the three industries to achieve industrial revitalization;implementing risk management measures as a preventive strategy to ensure industrial stability;establishing incentive policies to foster production enthusiasm;and ultimately assisting farmers in increasing their income to achieve the overarching goal of improving the livelihoods of the population.
基金supported by the National Natural Science Foundation of China(No.81874369)the Excellent Youth Project of the Hunan Provincial Department of Education(No.22B0388)the Project of Hunan Administration of Traditional Chinese Medicine(No.B2023143)。
文摘Five new flavan-4-ol glycosides jixueqiosides A-E(1-5)and two new flavan glycosides jixueqiosides F and G(6 and 7),along with twelve known flavan-4-ol glycosides(8-19),were isolated from the roots of Pronephrium penangianum.Comprehensive spectral analyses,X-ray single-crystal diffraction,and theoretical electronic circular dichroism(ECD)calculations established structures and absolute configurations.A single crystal structure of flavan-4-ol glycoside(14)was reported for the first time,while the characteristic ECD and NMR data for all isolated flavan-4-ol glycosides(1-5,8-19)were analyzed,establishing a set of empirical rules.Activity screening of these isolates showed that 8 and 9 could inhibit the proliferation of MDA-MB-231 and MCF-7 cells with IC50 values of 7.93±2.85μmol·L^(-1)and 5.87±1.58μmol·L^(-1)(MDA-MB-231),and 2.21±1.38μmol·L^(-1)and 3.52±1.55μmol·L^(-1)(MCF-7),respectively.Western blotting and flow cytometry analyses demonstrated that 8 and 9 dose-dependently induced apoptosis in MDA-MB-231 cells by up-regulating BAX,activating caspase-3 and down-regulating BCL-2.Additionally,compound 8 affected autophagy-related proteins,increasing the ratio of LC3-II/LC3-I and Beclin-1 levels to inhibit MDA-MB-231 cell proliferation.Moreover,anti-inflammatory studies indicated that 2,3,7,13,14,and 18 moderately inhibited tumor necrosis factor-α(TNF-α),interleukin-6(IL-6),and nitric oxide(NO)release.
基金supported by the National Key R&D Program of China(No.2021YFC1808902)the National Natural Science Foundation of China(No.31770152)+1 种基金Shaanxi Fundamental Science Research Project for Chemistry&Biology(No.22JHZ008)the Natural Science Foundation of Gansu Province of China(No.23JRRM738).
文摘High molecular weight polycyclic aromatic hydrocarbons(HMW-PAHs)pose significant environmental challenges due to their complex structures and persistent toxicity,and are difficult to be degraded by bacteria.Fungi,however,possess the ability to overcome these challenges,primarily through various enzymes with broad substrate specificity,including cytochrome P450(CYP450),laccase,manganese peroxidase,lignin peroxidase.As a result,the development of efficient fungal strains capable of degrading HMW-PAHs is essential for advancing bioremediation strategies.In this study,Aspergillus fumigatus Z5 was isolated from a contaminated site and demonstrated a remarkable ability to degrade the highly recalcitrant benzo[a]pyrene,achieving a degradation rate of 75.43%.Transcriptomic analysis revealed significant upregulation of 34 CYP450 genes.Among these genes,CYP3A4(gene 8840)showed strong binding affinity for benzo[a]pyrene,as confirmed by molecular docking studies,indicating its key role in the biodegradable process.Furthermore,the metabolic network analysis showed that the electron transfer required for CYP450-mediated oxidative reactions enhanced mitochondrial oxidative phosphorylation and subsequently energy metabolism in A.fumigatus Z5.This metabolic coordination likely facilitates the complete degradation of benzo[a]pyrene.Our study illuminates the fundamental roles of CYP450 from A.fumigatus Z5 in benzo[a]pyrene degradation and provides novel insight into designing and implementing enhanced bioremediation strategies.
基金supported by the Research Fund of the State Key Laboratory of Solidification Processing(NPU)China(No.2022-QZ-03)+2 种基金the Open Research Fund of National Key Laboratory of Special Vehicle Design,Manufacturing Integration Technology(No.GZ2022KF001).Shenzhen Science and Technology Program(No.JCYJ20210324142805014)Shaanxi Province Youth Science,Technology New Star(No.2022KJXX-20)the Opening Project of State Key Laboratory of Polymer Materials Engineering(Sichuan University)(No.sklpme2022-4-05).
文摘One-dimensional nanomaterials with hollow structures could provide large space for ion storage and charge accumulation.Herein,TiO_(2)/MoSe_(2)-Carbon nanotube composite(NT)materials were designed and fabricated by the template method and the chelation coordination reaction.The stability and conductivity were improved by the presence of titanium and hollow tubular-architecture carbon in the whole structure.As a result,the as-prepared TiO_(2)/MoSe_(2)-Carbon hybrid achieved a high-rate performance of 760.0 mAh·g^(−1) at a current density of 0.1 A·g^(−1),while still obtaining stability after 300 charge/discharge cycles.The enhancement of the lithium storage capacity mainly contributed to the acceleration of the electron conductivity and the storage kinetics.Moreover,the hollow structure reduced the volume strain and stress caused by the rapid insertion and removal of lithium ions,which ensured the favorable stability of lithium storage.The experiment shows that the kinetic of the TiO_(2)/MoSe_(2)-carbon hybrid during the lithium storage process is dominated by the pseudocapacitance mechanism.This work provides a new idea and scheme for the design and preparation of hierarchical nanotube composite electrode materials.
文摘Oxidative coupling of methane(OCM)is a catalytic partial oxidation process that directly converts methane into C_(2) products.For this high temperature reaction,understanding the radical behavior through experimental investigation is important in correlating the catalytic activity and the products.In this work,a spatial resolution online mass spectrometry(MS)system was developed and applied to a Mn-Na_(2)WO_(4)/SiO_(2) catalyzed OCM system.In addition to the residue gas analysis,the system obtained the distribution information of the reactants and products in the reactor.At various setting temperatures,all species online MS signals were collected at different positions,mapping the reaction activity covering parameters including temperature,time and space.The distribution behavior of the catalytic activity,selectivity,and apparent activation energy were kinetically analyzed.Selectivity and additional carbon balance analysis strongly supported the radical coupling model of OCM and indicated that after the catalytic bed layer,there is a significant length in the reactor(>2 mm)filled with radicals.Based on the result,a designed new method by tuning the temperature field in the reactor was found effectively to improve the catalytic activity,especially the C_(2) yield from 702 to 773℃.
基金supported by the National Key R&D Program of China(Grant No.2022YFC3003601)Joint Funds of the National Natural Science Foundation of China Project on Earthquake Science(Grant No.U2239252)the program of the Innovative Research Team in China Earthquake Administration.
文摘Surface irregularities,such as hills and ridges,can significantly amplify ground motion caused by earthquakes.Therefore,in this study,we propose an analytical solution model to investigate the interaction between an asymmetric triangular hill on Earth and SH waves.Firstly,based on the development of wave functions and regional matching techniques,we introduce a semi-circular artificial auxiliary boundary,dividing the solution model into a semi-infinite body containing a semi-circular depression and an asymmetric fan-shaped region.Secondly,we derive the domain function form applicable to solving asymmetric problems.Utilizing the theory of complex variables,we establish a well-posed matrix for solving domain functions within the same coordinate system.Numerical results demonstrate that the scattering of SH waves by a protuberance is jointly influenced by the geometric parameters of the hill and the angle of incidence.Additionally,the frequency of the incident wave also has a certain degree of impact on the displacement amplitude.This study elucidates the scattering mechanism of SH waves by complex boundaries,providing a theoretical reference for building site selection and seismic design.In practical problems,the asymmetric assumption is more applicable than the symmetry assumption.
基金supported by the Natural Science Foundation of Anhui Province(No.228085ME142)the Comprehensive Research Facility for the Fusion Technology Program of China(No.20180000527301001228)the Open Fund of the Magnetic Confinement Fusion Laboratory of Anhui Province(No.2024AMF04003)。
文摘As the plasma current power in tokamak devices increases,a significant number of stray magnetic fields are generated around the equipment.These stray magnetic fields can disrupt the operation of electronic power devices,particularly transformers in switched-mode power supplies.Testing flyback converters with transformers under strong background magnetic fields highlights electromagnetic compatibility(EMC)issues for such switched-mode power supplies.This study utilizes finite element analysis software to simulate the electromagnetic environment of switched-mode power supply transformers and investigates the impact of variations in different magnetic field parameters on the performance of switched-mode power supplies under strong stray magnetic fields.The findings indicate that EMC issues are associated with transformer core saturation and can be alleviated through appropriate configurations of the core size,air gap,fillet radius,and installation direction.This study offers novel solutions for addressing EMC issues in high magnetic field environments.
文摘BACKGROUND Omental torsion(OT)is a rare cause of acute abdomen,it can be difficult to diagnose preoperatively and is frequently misdiagnosed.Computed tomography(CT)is the primary imaging modality for OT.It typically shows the swirl sign.contrast-enhanced CT can better visualize the central vascular structure of the mass,thus improving the diagnostic accuracy for OT.Surgical resection is the mainstay of treatment for OT.Laparoscopy allows direct visualization of the primary torsion site and comprehensive abdominal exploration,thereby decreasing misdiagnoses.It is a safe and reliable approach for OT treatment,which offers the advantages of minimal trauma,mild postoperative pain,and rapid recovery for stylistic precision.CASE SUMMARY A 48-year-old man was admitted to our hospital due to lower right abdominal pain for the preceding 70 hours.Physical examination revealed lower right abdominal muscle strain,tenderness,and rebound pain,but no mass was palpable.Contrast-enhanced CT revealed a thickened,blurred omentum with swirling changes in the right abdomen.Laparoscopic exploration and omentectomy were performed in the emergency setting.The procedure revealed 50 mL of dark-red bloody ascites in the pelvis and twisting of the right omentum along its longitudinal axis,with a 10 cm×8 cm purple-black necrosis at the distal end.Postsurgical pathology revealed omental hemorrhage,degeneration,and necrosis.The patient had an uneventful recovery and was discharged on the fourth postoperative day.During the subsequent nine-month follow-up,he remained asymptomatic.CONCLUSION OT is a rare disease that lacks specific clinical manifestations.Abdominal contrast-enhanced CT plays a crucial role in diagnosing OT,and laparoscopic surgery is a safe and effective diagnostic and therapeutic approach.
基金supported by the National Natural Science Foundation of China(31970222,31770569,31500454,31500165,32260060,32270217,32260056,31970223,32400180)the Science and Technology Basic Resources Investigation Program of China(2017FY100100,2017FY100102)+7 种基金Biodiversity Conservation Program of Chinese Academy of Sciences(ZSSD-013)National Key Research and Development Program of China(2022YFC2601200,2023YFF0805800)Yunnan Fundamental Research Projects(202201AS070055,202301AU070224)the 14th Five-Year Plan of Xishuangbanna Tropical Botanical Garden,Chinese Academy of Sciences(XTBG-1450101)Australian Research Council grant(DP130104314)RSNZ Marsden grant(11-UOO-043)Xingdian Talent Support Program(XDRC-QNRC-2022-0323)Shandong Provincial Natural Science Foundation(ZR2022QC214).
文摘Over the past two decades,our understanding of Lauraceae,a large family of woody plants,has undergone significant advances in phylogeny,taxonomy,and biogeography.Molecular systematic studies have elucidated the basic relationships within the family with plastid phylogenomic analyses providing robust support for deep-level relationships between Lauraceae lineages,leading to the recognition of nine tribes:Hypodaphnideae,Cryptocaryeae,Cassytheae,Neocinnamomeae,Caryodaphnopsideae,Mezilaureae,Perseeae,Laureae,and Cinnamomeae,with Mezilaureae validated here.Nuclear genomes and comparative genomics studies have also clarified aspects of the family’s evolutionary history and metabolic diversity.Taxonomic studies have focused mainly on the most diverse regions,e.g.,tropical Asia,tropical America,and Africa(Madagascar),with six new genera described and five reinstated since the last major overview of the family.The extensive fossil record suggests that Lauraceae diversified globally during the Late Cretaceous and Early Cenozoic.Biogeographic studies indicate that different lineages of the family are sorted into Gondwanan and Laurasian lineages,with patterns resulting from the disruption of boreotropical flora and multiple long-distance dispersal events.Phylogeographic studies,predominantly from East Asia,have shown patterns of in situ survival and demographic stability or expansion during the Quaternary.Nevertheless,many systematic relationships within the family remain unresolved and further research is needed into the complex biogeographic history and ecological roles of Lauraceae.A multifaceted approach integrating genomic studies,field work,morphological and ecological investigations is therefore needed to understand the evolution and diversity of this ecologically and economically significant plant family.
基金financially supported by the grants from the earmarked fund for Xinjiang Agriculture Research System,China(XJARS-06)the Key Research and Development Task Special Project of Xinjiang,China(2022B02002-3)+1 种基金the Tianshan Talent Training Program,China(2023TSYCLJ0015)the Key Research and Development Program of Xinjiang Uygur Autonomous Region,China(2023B02017).
文摘Melon is a globally cultivated horticultural crop with a predominantly hybrid commercial seed market in China.Seedling morphology,particularly hypocotyl color,is a valuable trait for rapid F1 hybrid seed purity assessment.While green hypocotyls are common,white hypocotyls are rare in melon germplasm.This study identified a mutant with white hypocotyl but green leaves from the heavy ion beam mutant library.Genetic analysis revealed that a single recessive gene controlled the white hypocotyl,designated CmGhc1.A single-base deletion in the fifth exon of CmGhc1 led to a truncated CmGhc1 lacking the HTH-MYB DNA binding domain,likely affecting its transcriptional activity.CmGhc1 was localized in the nucleus,and yeast two-hybrid analysis and a dual-LUC assay demonstrated it as a transcription repressor.Furthermore,a KASP marker(hc1)was developed and verified as a functional marker for breeding white hypocotyl germplasms in melon.RNA-seq data revealed that CmGhc1 significantly affected the transcription of genes related to chlorophyll metabolism and photosynthesis in hypocotyl.In summary,these findings contribute to our understanding of chloroplast biogenesis and provide a valuable tool for melon breeding.
基金Project supported by the Jiangxi Provincial Natural Science Foundation(20224BAB212026,20224BAB214026,20242BAB23008)National Natural Science Foundation of China(62361033)。
文摘Nanostructured materials with small particle sizes have been widely used in resistive gas sensors due to their high specific surface area and surface activity.However,phenomena including agglomeration,growth and structural damage of nanostructures are almost inevitable during the processes of device fabrication or sensing tests,which makes it difficult to exert their expected activity.To address this issue,rare earth metal oxide CeO_(2)was chosen as the model material to explore confined nanostructures in resistive gas sensors.The experiment successfully achieves the preparation of confined CeO_(2)nanoparticles film using a pulsed laser deposition combined with rapid annealing technology.It is found that the confined CeO_(2)nanoparticles film enables the efficient detection of volatile organic compound triethylamine,demonstrating a significant response of 20(Ra/Rg)towards 100 ppm triethylamine,a fast response of 2 s,excellent stability and selectivity.By in-situ confinement in porous carbon matrix,dispersion and fixation of CeO_(2)nanoparticles can be achieved,thereby fully utilizing their high surface activity.In addition,the porous carbon matrix can serve as a transport pathway for the target gas molecules and electrons,enabling efficient gas-solid reactions and effective collection of gas sensing signals.More importantly,the confined CeO_(2)nanoparticles film was grown in-situ on commercial alumina flats gas sensing substrate,which can be directly used as sensing layer for gas sensors.Based on first-principles calculations,the triethylamine sensing mechanism of the confined CeO_(2)nanoparticles film was systematically analyzed at the atomic and electronic scale.This study offers new insights into enhancing the gas sensing performance of resistive gas sensors through confined nanostructures design.
基金supported by the National Natural Science Foundation of China(Grant Nos.12074382,11474285,and 12464012)the crew of the Center for Computational Materials Science,Institute for Materials Research of Tohoku University,and the supercomputer resources through the HPCI System Research Project(hp200246).
文摘A potential orthorhombic phase of Ta_(2)O_(5),designated as Y-Ta_(2)O_(5),is predicted under high-pressure conditions using density functional theory(DFT)combined with structural search algorithms.This phase,containing four formula units per unit cell(Z=4),exhibits the highest Ta-O coordination numbers reported to date.Y-Ta_(2)O_(5)is identified as the most energetically stable form of Ta_(2)O_(5)within the pressure range of approximately 70 GPa to at least 200 GPa.Both standard DFT-GGA and higher-accuracy GW calculations indicate that Y-Ta_(2)O_(5)is a wide-bandgap semiconductor with a direct bandgap.Furthermore,nuclear quantum effects(NQEs)introduce nontrivial corrections to external pressure at fixed volumes,underscoring their significance in high-pressure phase stability analyses.
基金financially supported by the National Key Research and Development Program of China(No.2023YFD2200505)the National Natural Science Foundation of China(No.22202105)+3 种基金the Natural Science Foundation of Jiangsu Higher Education Institutions of China(No.21KJA150003)the Innovation and Entrepreneurship Team Program of Jiangsu Province(No.JSSCTD202345)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX23_1163)the China Postdoctoral Science Foundation(Nos.2023M731703 and 2024T170415)
文摘The oxidation of lignin model compounds to esters via C-C bond cleavage has attracted considerable attention,as esters could be used as important polymer precursors and pharmaceutical intermediates.However,most studies focus on designing homogeneous or noble metal catalysts and conducting the reactions under basic conditions.Here,we report an efficient process for the C-C bond cleavage of lignin model compounds and selectively producing esters over different shaped CeO_(2)(i.e.,nanospheres(S),nanorods(R),nanoparticles(P),and nanocubes(C))under base-free conditions.Specifically,the yield of methyl anisate from the aerobic oxidation of l-(4-methoxyphenyl)ethanol reaches 77.6%over CeO_(2)-S in one hour(91%in 9 h),exhibiting higher performance compared to other evaluated CeO_(2)catalysts(6.4%-40.2%).Extensivecharacterizations and experimental investigations reveal that the density of weak base sites and oxygen vacancies on the CeO_(2)surface is positively correlated with the yield of methyl esters.Furthermore,the reaction pathway is investigated,which confirms that 1-(4-methoxyphenyl)ethanol first undergoes two reactions(i.e.,etherification and dehydrogenation)to produce intermediates of1-methoxy-4-(1-methoxy-ethyl)-benzene and 1-(4-methoxyphenyl)ethanone,respectively,followed by a series of functional group transformations to generate the targeted methyl anisate ultimately.
基金financially supported by the Shenzhen Science and Technology Project(Project Nos.JCYJ20220818102201003,JCYJ20220818100001002)the Shenzhen Sustainable Development Special Project(Project No.KCXFZ20230731094500001)+1 种基金the National Natural Science Foundation of China(Project Nos.51975597,52175446)the Natural Science Foundation of Guangdong Province(Project No.2022B1515020011)。
文摘Magnetically responsive microstructured functional surface(MRMFS),capable of dynamically and reversibly switching the surface topography under magnetic actuation,provides a wireless,noninvasive,and instantaneous way to accurately control the microscale engineered surface.In the last decade,many studies have been conducted to design and optimize MRMFSs for diverse applications,and significant progress has been accomplished.This review comprehensively presents recent advancements and the potential prospects in MRMFSs.We first classify MRMFSs into one-dimensional linear array MRMFSs,two-dimensional planar array MRMFSs,and dynamic self-assembly MRMFSs based on their morphology.Subsequently,an overview of three deformation mechanisms,including magnetically actuated bending deformation,magnetically driven rotational deformation,and magnetically induced self-assembly deformation,are provided.Four main fabrication strategies employed to create MRMFSs are summarized,including replica molding,magnetization-induced self-assembly,laser cutting,and ferrofluid-infused method.Furthermore,the applications of MRMFS in droplet manipulation,solid transport,information encryption,light manipulation,triboelectric nanogenerators,and soft robotics are presented.Finally,the challenges that limit the practical applications of MRMFSs are discussed,and the future development of MRMFSs is proposed.
基金supported by the Province Natural Science Foundation of Hunan,China(2022JJ50048)Hunan Agriculture Research System(HARS-11).
文摘Lily-Ziziphi Spinosae Semen decoction(LZ)is known for its blood nourishing,mind calming,body sedation,and sleep promoting effects in traditional Chinese medicine.However,its material basis and underlying mechanisms have not yet been clearly defined.This study applies liquid chromatography-mass spectrometry,network pharmacology,and animal studies to reveal the material basis and sleep-improving mechanisms of LZ.The mixed decoction(LZ-ME)and single decoction(LZ-SE)were prepared to study their chemical components.Network pharmacology was used to predict the sleep-improving targets and signaling pathways of LZ.ICR mice were intragastrically administered saline(NC),melatonin(positive control group,0.50 mg/kg),low(12.90 g/kg),medium(25.70 g/kg),and high(38.60 g/kg)dose of LZ-ME and LZ-SH for 30 days.The results showed that LZ-ME could prolong the sleep duration and shorten the sleep latency in sodium barbiturate induced mice model.The results of chemical composition showed that total polysaccharides,total flavonoids,total saponins,and total alkaloids in LZ-ME were significantly higher than those in LZ-SE(177.20%,82.34%,30.58%,and 11.66%,respectively).A total of 58 chemical components were identified by ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UPLC-QTOF-MS),and 8 representative difference components of LZ-ME and LZ-SE were found.LZ-ME significantly increased tumor necrosis factor-α(TNF-α)in mice serum and neurotransmitterγ-aminobutyric acid(GABA)levels in mice hippocampus,decreased dopamine(DA)and glutamate(Glu)levels in mice hippocampus(P<0.05).Furthermore,LZ-ME up-regulated the abundance of the beneficial bacteria Lactobacillus and Eubacterium_R,down-regulated the abundance of the harmful bacteria Lachnospiraceae etc.The polysaccharides,flavonoids(spinosin and 6‴-feruloylspinosin)and saponins(jujuboside A and jujuboside B)were the main material bases for the sleep-promoting effects of LZ.These compounds may directly enhance levels of the GABA,reduced levels of Glu and DA and improve TNF-αlevels.And they also may indirectly regulate GABA levels by influencing the relative abundance of Lactobacillus and Eubacterium.