To mitigate the impact of interdiffusion reactions between the silicide slurry and Ta12W alloy substrate during vacuum sintering process on the oxidation resistance of the silicide coating,a micro-arc oxidation pretre...To mitigate the impact of interdiffusion reactions between the silicide slurry and Ta12W alloy substrate during vacuum sintering process on the oxidation resistance of the silicide coating,a micro-arc oxidation pretreatment was employed to construct a Ta_(2)O_(5)ceramic layer on the Ta12W alloy surface.Subsequently,a slurry spraying-vacuum sintering method was used to prepare a Si-Cr-Ti-Zr coating on the pretreated substrate.Comparative studies were conducted on the microstructure,phase composition,and isothermal oxidation resistance(at 1600℃)of the as-prepared coatings with and without the micro-arc oxidation ceramic layer.The results show that the Ta_(2)O_(5)layer prepared at 400 V is more continuous and has smaller pores than that prepared at 350 V.After microarc oxidation pretreatment,the Si-Cr-Ti-Zr coating on Ta12W alloy consists of three distinct layers:an upper layer dominated by Ti_(5)Si_(3),Ta_(5)Si_(3),and ZrSi;a middle layer dominated by TaSi_(2);a coating/substrate interfacial reaction layer dominated by Ta_(5)Si_(3).Both the Si-Cr-Ti-Zr coatings with and without the Ta_(2)O_(5)ceramic layer do not fail after isothermal oxidation at 1600℃for 5 h.Notably,the addition of the Ta2O5 ceramic layer reduces the high-temperature oxidation rate of the coating.展开更多
The limited high-temperature oxidation resistance of Mg alloys is a key factor restricting their development and application.The addition of some rare earth elements(REs),owing to their unique physical and chemical pr...The limited high-temperature oxidation resistance of Mg alloys is a key factor restricting their development and application.The addition of some rare earth elements(REs),owing to their unique physical and chemical properties,can significantly enhance the oxidation resistance of Mg alloys.Based on our previous study,we conclude that REs such as Gd,Y,and Ce enhance the oxidation resistance of Mg-RE alloys.This article comprehensively reviews recent research progress on high-temperature oxidation behavior and the potential mechanism in Mg-RE alloys.Based on the thermodynamic and kinetic analyses,the evolution of the complex oxide system formed during the high-temperature oxidation of Mg-RE alloys is first summarized.The diffusion behavior and concentration control mechanisms of REs during the oxidation process and how these mechanisms affect the sustained growth of the oxide film and antioxidant properties were elucidated.Moreover,the different structures of the oxide films were classified,and their properties were discussed.Finally,this paper introduces the applications of commonly used REs in Mg alloys and frontier research on their oxidation mechanisms.Based on the above review,we propose that future research perspectives can be explored in terms of expanding the experimental temperature range for oxidation tests,optimizing the chemical composition by adding trace REs to study their synergistic mechanism,revealing the underlying oxidation mechanism through advanced in situ microscopic characterization methods,and investigating the mechanical properties of oxide films using diverse approaches.展开更多
TiB_(2)coatings can significantly enhance the high-temperature oxidation resistance of molybdenum,which would broaden the application range of molybdenum and alloys thereof.However,traditional methods for preparing Ti...TiB_(2)coatings can significantly enhance the high-temperature oxidation resistance of molybdenum,which would broaden the application range of molybdenum and alloys thereof.However,traditional methods for preparing TiB_(2)coatings have disadvantages such as high equipment costs,complicated processes,and highly toxic gas emissions.This paper proposes an environmentally friendly method,which requires inexpensive equipment and simple processing,for preparing TiB_(2)coating on molybdenum via electrophoretic deposition within Na3AlF6-based molten salts.The produced TiB_(2)layer had an approximate thickness of 60μm and exhibited high density,outstanding hardness(38.2 GPa)and robust adhesion strength(51 N).Additionally,high-temperature oxidation experiments revealed that,at900℃,the TiB_(2)coating provided effective protection to the molybdenum substrate against oxidation for 3 h.This result indicates that the TiB_(2)coating prepared on molybdenum using molten salt electrophoretic deposition possesses good high-temperature oxidation resistance.展开更多
In this study,the design,analysis,manufacturing,and testing of a 3D-printed conformal microstrip array antenna for high-temperature environments is presented.3D printing technology is used to fabricate a curved cerami...In this study,the design,analysis,manufacturing,and testing of a 3D-printed conformal microstrip array antenna for high-temperature environments is presented.3D printing technology is used to fabricate a curved ceramic substrate,and laser sintering and microdroplet spraying processes are used to add the conductive metal on the curved substrate.The problems of gain loss,bandwidth reduction,and frequency shift caused by high temperatures are addressed by using a proper antenna design,with parasitic patches,slots,and metal resonant cavities.The antenna prototype is characterized by the curved substrates and the conductive metals for the power dividers,the patch,and the ground plane;its performance is examined up to a temperature of 600℃in a muffle furnace and compared with the results from the numerical analysis.The results show that the antenna can effectively function at 600℃and even higher temperatures.展开更多
Rationale:This case report describes a couple with recurrent fertilization failure despite undergoing multiple cycles of intracytoplasmic sperm injection(ICSI).The principal clinical concern was suspected oocyte activ...Rationale:This case report describes a couple with recurrent fertilization failure despite undergoing multiple cycles of intracytoplasmic sperm injection(ICSI).The principal clinical concern was suspected oocyte activation deficiency(OAD),in which fertilization is impeded due to the oocyte’s inability to initiate embryogenesis,commonly attributed to inadequate intracellular calcium(Ca^(2+))release following sperm injection.Patient concerns:The couple repeatedly experienced complete or near-complete fertilization failure in previous ICSI cycles,raising suspicion of an underlying oocyte activation defect.Diagnosis:Based on the repeated absence of fertilization post-ICSI and clinical history,a diagnosis of suspected OAD leading to recurrent ICSI fertilization failure was considered.Interventions:Artificial oocyte activation(AOA)using the calcium ionophore A23187 was performed.After ICSI,unfertilized oocytes were exposed to the ionophore to induce Ca^(2+)influx,simulating physiological calcium oscillations essential for oocyte activation.The efficacy of intervention was evaluated through subsequent embryonic development,morphological grading,and chromosomal integrity.Outcomes:Following AOA treatment,successful oocyte activation occurred,resulting in the formation of high-grade embryos with normal developmental progression.Chromosomal analysis revealed no detectable abnormalities,indicating genomic stability.Lessons:Calcium ionophore–mediated AOA may serve as an effective adjunct in cases of recurrent ICSI failure attributed to OAD.This case highlights the importance of individualized therapeutic strategies in assisted reproduction;however,further research is needed to refine protocols,validate broader clinical efficacy,and assess long-term safety,including potential epigenetic risks.展开更多
Peroxymonosulfate(PMS)-assisted visible-light photocatalytic degradation of organic pollutants using graphitic carbon nitride(g-C_(3)N_(4))presents a promising and environmentally friendly approach.However,pristine g-...Peroxymonosulfate(PMS)-assisted visible-light photocatalytic degradation of organic pollutants using graphitic carbon nitride(g-C_(3)N_(4))presents a promising and environmentally friendly approach.However,pristine g-C_(3)N_(4) suffers from limited visible-light absorption and low charge-carrier mobility.In this study,a phosphorus-doped tubular carbon nitride(5P-TCN)was synthesized via a precursor self-assembly method using phosphoric acid and melamine as raw materials,eliminating the need for organic solvents or templates.The 5P-TCN catalyst demonstrated enhanced visible-light absorption,improved charge transfer capability,and a 5.25-fold increase in specific surface area(31.092 m^(2)/g),which provided abundant active sites to efficiently drive the PMS-assisted photocatalytic reaction.The 5P-TCN/vis/PMS system exhibited exceptional degradation performance for organic pollutants across a broad pH range(3–9),achieving over 92%degradation of Rhodamine B(RhB)within 15 min.Notably,the system retained>98%RhB degradation efficiency after three consecutive operational cycles,demonstrating robust operational stability and reusability.Moreover,key parameters influencing,active radi-cals,degradation pathways,and potential mechanisms for RhB degradation were systematically investigated.This work proposes a green and cost-effective strategy for developing high-efficiency photocatalysts,while demon-strating the exceptional capability of a PMS-assisted photocatalytic system for rapid degradation of RhB.展开更多
Given that platinum-based drugs are widely used clinically as chemotherapeutic agents,their severe toxic side effects have attracted significant attention.Consequently,the development of novel nanoprodrugs based on lo...Given that platinum-based drugs are widely used clinically as chemotherapeutic agents,their severe toxic side effects have attracted significant attention.Consequently,the development of novel nanoprodrugs based on low-toxicity tetravalent platinum(Pt(Ⅳ))com plexes holds substantial research value.Herein,we discovered that coumarin derivatives exhibit inherent antitumor efficacy and significantly enhance superoxide anion radicals(·O_(2)^(-))generation in aqueous solutions under ultrasound(US)irradiation.Given that·O_(2)^(-)is known to mediate the reduction of Pt(Ⅳ)to divalent platinum(Pt(Ⅱ)),we engineered an US-responsive dual-drug nanoprodrug(P-cisPt(Ⅳ)@5-MOP).This nanoprodrug was prepared by covalently conjugating Pt(Ⅳ)and methoxy polyethylene glycol hydroxyl(m PEG-OH)to a poly(_(L)-glutamic acid)(PLG)carrier,followed by encapsulating coumarin derivatives.Under low-intensity US irradiation(1.5 W/cm^(2),1 MHz,10 min),P-cisPt(Ⅳ)@5-MOP achieved a Pt(Ⅳ)reduction rate of 91.4%.Furthermore,upon US exposure,its half-maximal inhibitory concentration(IC_(50))against 4T1 breast cancer cells decreased dramatically from 25.7μmol/L to 0.1μmol/L.Remarkably,this system combined with US therapy yielded a tumor inhibition rate of 90.9%,with 40%of tumor-bea ring mice achieving com plete eradication of tumors,while exhibiting low systemic toxicity.Collectively,this work not only identifies a novel sonosensitizer capable of generating·O_(2)^(-)but also develops a new class of ultrasound-activatable Pt(Ⅳ)nanoprodrug.展开更多
Triclosan(TCS) poses harmful risks to ecosystems and human health owing to its endocrine-disrupting effects.Therefore,developing an efficient and sustainable technology to degrade TCS is urgently needed.Herein,cobalt ...Triclosan(TCS) poses harmful risks to ecosystems and human health owing to its endocrine-disrupting effects.Therefore,developing an efficient and sustainable technology to degrade TCS is urgently needed.Herein,cobalt oxyhydroxide @covalent organic frameworks(CoOOH@COFs) S-scheme heterojunction was synthesized,which combined the visible-light-driven photocatalysis and peroxymonosulfate(PMS) activation to synergistically generate abundant reactive oxygen species(ROSs) for TCS degradation.The degradation efficiency of TCS reached 100 % within 8 min in the Vis-CoOOH@COFs/PMS system,and the reaction rate constant was 0.456 min^(-1),which was nearly 1.90 and 2.85 times that of single Co OOH and COFs,and2.36 times that under dark condition,respectively.The density functional theory(DFT) calculations confirmed the energy band bending of CoOOH@COFs and S-scheme charge transport from COFs to Co OOH.Both experimental and theoretical analyses indicated that Co OOH@COFs in photocatalytic-PMS activation systems synergistically facilitated photo-generated carrier separation,enhanced interfacial electron transfer,accelerated PMS activation,and generated multiple ROSs.In particular,photogenerated electrons(e^(-))accelerated the Co(Ⅲ)/Co(Ⅱ) redox cycle,while the PMS captured the e-,which significantly decreased the charge combination of Co OOH@COFs.Radicals(O_(2)^(·-),^(·)OH,and SO_(4)^(·-)) and non-radicals(such as ^(1)O_(2),h^(+),and e^(-)) were both presented in the Vis-CoOOH@COFs/PMS system,with O_(2)^(-) playing a dominant role in TCS degradation.Furthermore,the pathway of TCS degradation and toxicity of intermediates were explored by DFT calculation and transformation product identification.Importantly,the environmentally friendly CoOOH@COFs S-scheme heterojunction exhibited excellent stability and reusability.In conclusion,this study innovatively designed an S-scheme heterojunction in the photocatalytic-PMS activation system,providing guidance and theoretical support for efficient and eco-friendly wastewater treatment.展开更多
Cells of the central nervous system(CNS)are privileged in lying behind the blood-brain barrier(BBB).Unlike blood vessels in other organs,CNS blood vessels are unique in displaying high electrical resistance and low pe...Cells of the central nervous system(CNS)are privileged in lying behind the blood-brain barrier(BBB).Unlike blood vessels in other organs,CNS blood vessels are unique in displaying high electrical resistance and low permeability.With this unique structure and function,the BBB prevents potentially harmful blood components such as serum proteins,inflammatory cytokines,and inflammatory leukocytes from entering the hallowed space of the CNS and wreaking havoc.In addition to these“tightness”properties,the BBB has an array of specialized transporters designed to import essential nutrients.展开更多
The functional properties of glasses are governed by their formation history and the complex relaxation processes they undergo.However,under extreme conditions,glass behaviors are still elusive.In this study,we employ...The functional properties of glasses are governed by their formation history and the complex relaxation processes they undergo.However,under extreme conditions,glass behaviors are still elusive.In this study,we employ simulations with varied protocols to evaluate the effectiveness of different descriptors in predicting mechanical properties across both low-and high-pressure regimes.Our findings demonstrate that conventional structural and configurational descriptors fail to correlate with the mechanical response following pressure release,whereas the activation energy descriptor exhibits robust linearity with shear modulus after correcting for pressure effects.Notably,the soft mode parameter emerges as an ideal and computationally efficient alternative for capturing this mechanical behavior.These findings provide critical insights into the influence of pressure on glassy properties,integrating the distinct features of compressed glasses into a unified theoretical framework.展开更多
Lithium-ion batteries(LIBs)suffer from float charge failure in the grid-scale storage market.However,the lack of a unified descriptor for the diverse reasons behind float charge failure poses a challenge.Here,a quanti...Lithium-ion batteries(LIBs)suffer from float charge failure in the grid-scale storage market.However,the lack of a unified descriptor for the diverse reasons behind float charge failure poses a challenge.Here,a quantitative analysis of active lithium loss is conducted across multiple temperatures into float charge of Li(Ni_(0.5)Co_(0.2)Mn_(0.3))O_(2)–graphite batteries.It is proposed that the active lithium loss can be used as a descriptor to describe the reasons for float charge quantitatively.Approximately 6.88%and 0.96%of active lithium are lost due to solid electrolyte interphase thickening and lithium deposition,which are primary and secondary failure reasons,respectively.These findings are confirmed by X-ray photoelectron spectroscopy depth profiling,scanning electron microscope,and accelerating rate calorimeter.Titration-gas chromatography and nuclear magnetic resonance are utilized to quantitatively analyze active lithium loss.Additionally,electrolyte decomposition at high temperatures also contributes to active lithium loss,as determined by Auger electron spectrum and nondestructive ultrasound measurements.Notably,no failure is detected in the cathode due to the relatively low working voltage of the float charge.These findings suggest that inhibiting active lithium loss can be an efficient way of delaying failure during high-temperature float charge processes in LIBs.展开更多
The burgeoning growth of the new energy vehicles and aviation industry has escalated the need for energy storage capacitors capable of stable operation in harsh environments.The advent of metal-polyimide complexes has...The burgeoning growth of the new energy vehicles and aviation industry has escalated the need for energy storage capacitors capable of stable operation in harsh environments.The advent of metal-polyimide complexes has illuminated a novel approach for preparing tem perature-resistant capacitors.However,the general application of these metal-polyimide com plexes is impeded by the high dielectric loss and low breakdown strength,consequences of main-chain coordination and excessive metal ions content.Herein,our study proposes a novel polyimideCu complex material(POP-Cu)predicated on side-chain-type pyridine-Cu coordination,utilizing the structural backbone PMDA-ODA of mature commercial PI(Kapton)with reliable performance.Owing to the high degree of freedom afforded by the side chain with suppressed relaxation activation energy and the long-range electron delocalization formed by d-πcoordination,the dielectric constant of this material containing merely 2.7 mol%Cu increases from 3.25(POPI)to 5.58,while maintaining a remarkably low dielectric loss of 0.0066.Meanwhile,this material exhibits a substantial DC breakdown strength of 436.2 MV·m^(-1)and a high energy density of 5.42 J·cm^(-3),coupled with superior mechanical and thermal properties.Even at 150℃,it retains over 90%of its room-temperature energy density,demon strating notable dielectric stability under high temperatures.These attributes underscore its promising application for capacitors operating in harsh environments.展开更多
This study investigated the physicochemical properties,enzyme activities,volatile flavor components,microbial communities,and sensory evaluation of high-temperature Daqu(HTD)during the maturation process,and a standar...This study investigated the physicochemical properties,enzyme activities,volatile flavor components,microbial communities,and sensory evaluation of high-temperature Daqu(HTD)during the maturation process,and a standard system was established for comprehensive quality evaluation of HTD.There were obvious changes in the physicochemical properties,enzyme activities,and volatile flavor components at different storage periods,which affected the sensory evaluation of HTD to a certain extent.The results of high-throughput sequencing revealed significant microbial diversity,and showed that the bacterial community changed significantly more than did the fungal community.During the storage process,the dominant bacterial genera were Kroppenstedtia and Thermoascus.The correlation between dominant microorganisms and quality indicators highlighted their role in HTD quality.Lactococcus,Candida,Pichia,Paecilomyces,and protease activity played a crucial role in the formation of isovaleraldehyde.Acidic protease activity had the greatest impact on the microbial community.Moisture promoted isobutyric acid generation.Furthermore,the comprehensive quality evaluation standard system was established by the entropy weight method combined with multi-factor fuzzy mathematics.Consequently,this study provides innovative insights for comprehensive quality evaluation of HTD during storage and establishes a groundwork for scientific and rational storage of HTD and quality control of sauce-flavor Baijiu.展开更多
Co-based alloy coating was prepared on Zr alloy using laser melting and cladding technique to study the difference in the high-temperature oxidation behavior between pure metal Co coatings and Co-T800 alloy coatings,a...Co-based alloy coating was prepared on Zr alloy using laser melting and cladding technique to study the difference in the high-temperature oxidation behavior between pure metal Co coatings and Co-T800 alloy coatings,as well as the wear resistance of the coatings.Besides,the effect of changing the laser melting process on the coatings was also investigated.The oxidation mass gain at 800–1200℃and the high-temperature oxidation behavior during high-temperature treatment for 1 h of two coated Zr alloy samples were studied.Results show that the Co coating and the Co-T800 coating have better resistance against high-temperature oxidation.After oxidizing at 1000℃for 1 h,the thickness of the oxide layer of the uncoated sample was 241.0μm,whereas that of the sample with Co-based coating is only 11.8–35.5μm.The friction wear test shows that the depth of the abrasion mark of the coated sample is only 1/2 of that of the substrate,indicating that the hardness and wear resistance of the Zr substrate are greatly improved.The disadvantage of Co-based coatings is the inferior corrosion resistance in 3.5wt%NaCl solution.展开更多
High-nickel ternary cathodes hold a great application prospect in solid-state lithium metal batteries to achieve high-energy density,but they still suffer from structural instability and detrimental side reactions wit...High-nickel ternary cathodes hold a great application prospect in solid-state lithium metal batteries to achieve high-energy density,but they still suffer from structural instability and detrimental side reactions with the solid-state electrolytes.To circumvent these issues,a continuous uniform layer polyacrylonitrile(PAN)was introduced on the surface of LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2) via in situ polymerization of acrylonitrile(AN).Furthermore,the partial-cyclized treatment of PAN(cPAN)coating layer presents high ionic and electron conductivity,which can accelerate interfacial Li+and electron diffusion simultaneously.And the thermodynamically stabilized cPAN coating layer cannot only effectively inhibit detrimental side reactions between cathode and solid-state electrolytes but also provide a homogeneous stress to simultaneously address the problems of bulk structural degradation,which contributes to the exceptional mechanical and electrochemical stabilities of the modified electrode.Besides,the coordination bond interaction between the cPAN and NCM811 can suppress the migration of Ni to elevate the stability of the crystal structure.Benefited from these,the In-cPAN-260@NCM811 shows excellent cycling performance with a retention of 86.8%after 300 cycles and superior rate capability.And endow the solid-state battery with thermal safety stability even at hightemperature extreme environment.This facile and scalable surface engineering represents significant progress in developing high-performance solid-state lithium metal batteries.展开更多
High-temperature industries,as the primary consumers of energy,are greatly concerned with energy savings.Designing refractory linings with low thermal conductivity to reduce heat dissipation through high-temperature f...High-temperature industries,as the primary consumers of energy,are greatly concerned with energy savings.Designing refractory linings with low thermal conductivity to reduce heat dissipation through high-temperature furnace linings is a critical concern.In this study,a series of novel entropy-stabilized spinel materials are reported,and their potential applications in high-temperature industries are investigated.XRD and TEM results indicate that all materials possess a cubic spinel crystal structure with the■space group.Furthermore,these materials exhibit good phase stability at high temperatures.All entropy-stabilized spinel aggregates demonstrated high refractoriness(>1800℃)and a high load softening temperature(>1700℃).The impact of configurational entropy on the properties of entropy-stabilized spinel materials was also studied.As configurational entropy increased,the thermal conductivity of the entropy-stabilized spinel decreased,while slag corrosion resistance deteriorated.For the entropy-stabilized spinel with a configurational entropy value of 1.126R,it showed good high-temperature stability,reliable resistance to slag attack,and a low thermal conductivity of 2.776 W·m^(-1)·K^(-1)at 1000℃.展开更多
The austenite(γ)reversely transformed from lath martensite(LM),lath bainite(LB),granular bainite(GB)and pearlite+ferrite(P+F)in a high-strength steel was studied at high temperatures using in-situ electron backscatte...The austenite(γ)reversely transformed from lath martensite(LM),lath bainite(LB),granular bainite(GB)and pearlite+ferrite(P+F)in a high-strength steel was studied at high temperatures using in-situ electron backscatter diffraction(EBSD).The memory effect of initial γ significantly affects the nucleation of the reverted γ in LM and GB structures,while a weak influence on that of LB and P+F structures.This results in a significant difference in γ grain size after complete austenitization,with the first two obtaining larger γ grains while the latter two are relatively small.Crystallographic analysis revealed that the reverted γ with acicular morphology(γA),most of which maintained the same orientation with the prior γ,dominated the reaustenitization behavior of LM and GB structures through preferential nucleation within γ grains and coalesced growth modes.Although globular reverted γ(γ_(G))with random orientation or large deviation from the prior γ can nucleate at the grain boundaries or within the grains,it is difficult for it to grow and play a role in segmenting and refining the prior γ due to the inhibition of γ_(A) coalescing.For LB and P+F structures,the nucleation rate of intragranular γ_(G) increases with increasing temperature,and always shows a random orientation.These γ_(G) grains can coarsen simultaneously with the intergranular γ_(G),ultimately playing a role in jointly dividing and refining the finalγgrains.Research also found that the differences in the effects of four different microstructures on revertedγnucleation are closely related to the variant selection of the matrix structure,as well as the content and size of cementite(θ).High density of block boundaries induced by weakening of variant selection and many fineθformed in the lath are the key to promoting LB structure to obtain more intragranular γ_(G) formation,as well as the important role of the large-sized θ in P+F structure.展开更多
Burial dissolution is a critical diagenetic process influencing ultra-deep carbonate reservoir development and preservation.Artificial carbonate samples with different internal structures were prepared,and high-temper...Burial dissolution is a critical diagenetic process influencing ultra-deep carbonate reservoir development and preservation.Artificial carbonate samples with different internal structures were prepared,and high-temperature and highpressure dissolution kinetic simulations were conducted.The results demonstrate that the intensity of burial dissolution is controlled by temperature and pressure,while tectonic-fluid activity influences the development pattern of burial dissolution,ultimately determining the direction of its differential modification.Extensive burial dissolution is likely to occur primarily at relatively shallow depths,significantly influencing reservoir formation,preservation,modification,and adjustment.The development of faults facilitates the maintenance of the intensity of burial dissolution.The maximum intensity of burial dissolution occurs at the tips and overlap zones of faults and intersections of multiple faults.The larger the scale of the faults,the more conducive it is to the development of burial dissolution.Burial dissolution fosters the formation of fault networks characterized by enhanced reservoir capacity and permeability.Burial dissolution controlled by episodic tectonic-fluid activity is a plausible explanation for forming the Tarim Basin's ultra-deep fault-controlled“stringbead-like”reservoirs.展开更多
Reproductive hormones associated with the hypothalamic-pituitary-gonadal(HPG)axis are closely linked to bone homeostasis.In this study,we demonstrate that Gonadotropin inhibitory hormone(GnIH,one of the key reproducti...Reproductive hormones associated with the hypothalamic-pituitary-gonadal(HPG)axis are closely linked to bone homeostasis.In this study,we demonstrate that Gonadotropin inhibitory hormone(GnIH,one of the key reproductive hormones upstream of the HPG axis)plays an indispensable role in regulating bone homeostasis and maintaining bone mass.We find that deficiency of GnIH or its receptor Gpr147 leads to a significant reduction in bone mineral density(BMD)in mice primarily by enhancement of osteoclast activation in vivo and in vitro.Mechanistically,GnIH/Gpr147 inhibits osteoclastogenesis by the PI3K/AKT,MAPK,NF-κB and Nfatc1 signaling pathways.Furthermore,GnIH treatment was able to alleviate bone loss in aging,ovariectomy(OVX)or LPS-induced mice.Moreover,the therapy using green light promotes the release of GnIH and rescues OVX-induced bone loss.In humans,serum GnIH increases and bone resorption markers decrease after green light exposure.Therefore,our study elucidates that GnIH plays an important role in maintaining bone homeostasis via modulating osteoclast differentiation and demonstrates the potential of GnIH therapy or green light therapy in preventing osteoporosis.展开更多
The research on high-performance electromagnetic wave absorption materials with high-temperature and oxidative stability in extreme environments is gaining popularity.Herein,the lightweight silicon carbide nanowires(S...The research on high-performance electromagnetic wave absorption materials with high-temperature and oxidative stability in extreme environments is gaining popularity.Herein,the lightweight silicon carbide nanowires(SiC_(nws))/SiC composites are fabricated with in-situ SiC interface on one-dimensional oriented SiC_(nws)skeleton,which collaborative configuration by 3D printing and freeze casting assembly.The con-structed porous structure optimizes the impedance matching degree and scattering intensity,the maximum effective absorption bandwidth(EAB_(max))of 5.9 GHz and the minimum reflection loss(RL_(min))of−41.4 dB can be realized.Considering the inherent oxidation resistance of SiC,the composites present well-maintained absorption performance at 600℃.Even at 1100℃,the EAB_(max)of 4.9 GHz and RLmin of−30.4 dB also demonstrate the high-temperature absorption stability of the composites,indicating exceptional wave absorption properties and thermal stability.The slight attenuation can be attributed to the decrease in impedance matching capability accompanying the elevated dielectric constant.This work clarifies the impact of structure and component synergy on wave absorption behavior,and offers a novel approach to producing high-performance and high-temperature resistance ceramic-based electromagnetic wave absorption materials suitable for extreme environments.展开更多
基金National Natural Science Foundation of China(52071274)Key Research and Development Projects of Shaanxi Province(2023-YBGY-442)Science and Technology Nova Project-Innovative Talent Promotion Program of Shaanxi Province(2020KJXX-062)。
文摘To mitigate the impact of interdiffusion reactions between the silicide slurry and Ta12W alloy substrate during vacuum sintering process on the oxidation resistance of the silicide coating,a micro-arc oxidation pretreatment was employed to construct a Ta_(2)O_(5)ceramic layer on the Ta12W alloy surface.Subsequently,a slurry spraying-vacuum sintering method was used to prepare a Si-Cr-Ti-Zr coating on the pretreated substrate.Comparative studies were conducted on the microstructure,phase composition,and isothermal oxidation resistance(at 1600℃)of the as-prepared coatings with and without the micro-arc oxidation ceramic layer.The results show that the Ta_(2)O_(5)layer prepared at 400 V is more continuous and has smaller pores than that prepared at 350 V.After microarc oxidation pretreatment,the Si-Cr-Ti-Zr coating on Ta12W alloy consists of three distinct layers:an upper layer dominated by Ti_(5)Si_(3),Ta_(5)Si_(3),and ZrSi;a middle layer dominated by TaSi_(2);a coating/substrate interfacial reaction layer dominated by Ta_(5)Si_(3).Both the Si-Cr-Ti-Zr coatings with and without the Ta_(2)O_(5)ceramic layer do not fail after isothermal oxidation at 1600℃for 5 h.Notably,the addition of the Ta2O5 ceramic layer reduces the high-temperature oxidation rate of the coating.
基金supported by the Key R&D Program of Shandong Province,China(No.2025CXGC 010412)the National Key Research and Development Program of China(No.2022YFB3709300)the National Natural Science Foundation of China(No.U21A2048).
文摘The limited high-temperature oxidation resistance of Mg alloys is a key factor restricting their development and application.The addition of some rare earth elements(REs),owing to their unique physical and chemical properties,can significantly enhance the oxidation resistance of Mg alloys.Based on our previous study,we conclude that REs such as Gd,Y,and Ce enhance the oxidation resistance of Mg-RE alloys.This article comprehensively reviews recent research progress on high-temperature oxidation behavior and the potential mechanism in Mg-RE alloys.Based on the thermodynamic and kinetic analyses,the evolution of the complex oxide system formed during the high-temperature oxidation of Mg-RE alloys is first summarized.The diffusion behavior and concentration control mechanisms of REs during the oxidation process and how these mechanisms affect the sustained growth of the oxide film and antioxidant properties were elucidated.Moreover,the different structures of the oxide films were classified,and their properties were discussed.Finally,this paper introduces the applications of commonly used REs in Mg alloys and frontier research on their oxidation mechanisms.Based on the above review,we propose that future research perspectives can be explored in terms of expanding the experimental temperature range for oxidation tests,optimizing the chemical composition by adding trace REs to study their synergistic mechanism,revealing the underlying oxidation mechanism through advanced in situ microscopic characterization methods,and investigating the mechanical properties of oxide films using diverse approaches.
基金supported by the Original Exploratory Program of the National Natural Science Foundation of China(No.52450012)。
文摘TiB_(2)coatings can significantly enhance the high-temperature oxidation resistance of molybdenum,which would broaden the application range of molybdenum and alloys thereof.However,traditional methods for preparing TiB_(2)coatings have disadvantages such as high equipment costs,complicated processes,and highly toxic gas emissions.This paper proposes an environmentally friendly method,which requires inexpensive equipment and simple processing,for preparing TiB_(2)coating on molybdenum via electrophoretic deposition within Na3AlF6-based molten salts.The produced TiB_(2)layer had an approximate thickness of 60μm and exhibited high density,outstanding hardness(38.2 GPa)and robust adhesion strength(51 N).Additionally,high-temperature oxidation experiments revealed that,at900℃,the TiB_(2)coating provided effective protection to the molybdenum substrate against oxidation for 3 h.This result indicates that the TiB_(2)coating prepared on molybdenum using molten salt electrophoretic deposition possesses good high-temperature oxidation resistance.
基金National Natural Science Foundation of China(No.U2241205)the Natural Science Basic Research Program of Shaanxi(Nos.2022JC-33,2023-GHZD-35,and 2024JC-ZDXM-25)+1 种基金the Fundamental Research Funds for the Central Universitiesthe National 111 Project to provide fund for conducting experiments。
文摘In this study,the design,analysis,manufacturing,and testing of a 3D-printed conformal microstrip array antenna for high-temperature environments is presented.3D printing technology is used to fabricate a curved ceramic substrate,and laser sintering and microdroplet spraying processes are used to add the conductive metal on the curved substrate.The problems of gain loss,bandwidth reduction,and frequency shift caused by high temperatures are addressed by using a proper antenna design,with parasitic patches,slots,and metal resonant cavities.The antenna prototype is characterized by the curved substrates and the conductive metals for the power dividers,the patch,and the ground plane;its performance is examined up to a temperature of 600℃in a muffle furnace and compared with the results from the numerical analysis.The results show that the antenna can effectively function at 600℃and even higher temperatures.
文摘Rationale:This case report describes a couple with recurrent fertilization failure despite undergoing multiple cycles of intracytoplasmic sperm injection(ICSI).The principal clinical concern was suspected oocyte activation deficiency(OAD),in which fertilization is impeded due to the oocyte’s inability to initiate embryogenesis,commonly attributed to inadequate intracellular calcium(Ca^(2+))release following sperm injection.Patient concerns:The couple repeatedly experienced complete or near-complete fertilization failure in previous ICSI cycles,raising suspicion of an underlying oocyte activation defect.Diagnosis:Based on the repeated absence of fertilization post-ICSI and clinical history,a diagnosis of suspected OAD leading to recurrent ICSI fertilization failure was considered.Interventions:Artificial oocyte activation(AOA)using the calcium ionophore A23187 was performed.After ICSI,unfertilized oocytes were exposed to the ionophore to induce Ca^(2+)influx,simulating physiological calcium oscillations essential for oocyte activation.The efficacy of intervention was evaluated through subsequent embryonic development,morphological grading,and chromosomal integrity.Outcomes:Following AOA treatment,successful oocyte activation occurred,resulting in the formation of high-grade embryos with normal developmental progression.Chromosomal analysis revealed no detectable abnormalities,indicating genomic stability.Lessons:Calcium ionophore–mediated AOA may serve as an effective adjunct in cases of recurrent ICSI failure attributed to OAD.This case highlights the importance of individualized therapeutic strategies in assisted reproduction;however,further research is needed to refine protocols,validate broader clinical efficacy,and assess long-term safety,including potential epigenetic risks.
文摘Peroxymonosulfate(PMS)-assisted visible-light photocatalytic degradation of organic pollutants using graphitic carbon nitride(g-C_(3)N_(4))presents a promising and environmentally friendly approach.However,pristine g-C_(3)N_(4) suffers from limited visible-light absorption and low charge-carrier mobility.In this study,a phosphorus-doped tubular carbon nitride(5P-TCN)was synthesized via a precursor self-assembly method using phosphoric acid and melamine as raw materials,eliminating the need for organic solvents or templates.The 5P-TCN catalyst demonstrated enhanced visible-light absorption,improved charge transfer capability,and a 5.25-fold increase in specific surface area(31.092 m^(2)/g),which provided abundant active sites to efficiently drive the PMS-assisted photocatalytic reaction.The 5P-TCN/vis/PMS system exhibited exceptional degradation performance for organic pollutants across a broad pH range(3–9),achieving over 92%degradation of Rhodamine B(RhB)within 15 min.Notably,the system retained>98%RhB degradation efficiency after three consecutive operational cycles,demonstrating robust operational stability and reusability.Moreover,key parameters influencing,active radi-cals,degradation pathways,and potential mechanisms for RhB degradation were systematically investigated.This work proposes a green and cost-effective strategy for developing high-efficiency photocatalysts,while demon-strating the exceptional capability of a PMS-assisted photocatalytic system for rapid degradation of RhB.
基金financially supported by the National Natural Science Foundation of China(Nos.52533015,52495013,52403211,52573183,52273157,52073279 and 52025035)Jilin Province,China(Nos.20250601009RC and 20230508102RC)Youth Innovation Promotion Association of the Chinese Academy of Sciences(No.2022224)。
文摘Given that platinum-based drugs are widely used clinically as chemotherapeutic agents,their severe toxic side effects have attracted significant attention.Consequently,the development of novel nanoprodrugs based on low-toxicity tetravalent platinum(Pt(Ⅳ))com plexes holds substantial research value.Herein,we discovered that coumarin derivatives exhibit inherent antitumor efficacy and significantly enhance superoxide anion radicals(·O_(2)^(-))generation in aqueous solutions under ultrasound(US)irradiation.Given that·O_(2)^(-)is known to mediate the reduction of Pt(Ⅳ)to divalent platinum(Pt(Ⅱ)),we engineered an US-responsive dual-drug nanoprodrug(P-cisPt(Ⅳ)@5-MOP).This nanoprodrug was prepared by covalently conjugating Pt(Ⅳ)and methoxy polyethylene glycol hydroxyl(m PEG-OH)to a poly(_(L)-glutamic acid)(PLG)carrier,followed by encapsulating coumarin derivatives.Under low-intensity US irradiation(1.5 W/cm^(2),1 MHz,10 min),P-cisPt(Ⅳ)@5-MOP achieved a Pt(Ⅳ)reduction rate of 91.4%.Furthermore,upon US exposure,its half-maximal inhibitory concentration(IC_(50))against 4T1 breast cancer cells decreased dramatically from 25.7μmol/L to 0.1μmol/L.Remarkably,this system combined with US therapy yielded a tumor inhibition rate of 90.9%,with 40%of tumor-bea ring mice achieving com plete eradication of tumors,while exhibiting low systemic toxicity.Collectively,this work not only identifies a novel sonosensitizer capable of generating·O_(2)^(-)but also develops a new class of ultrasound-activatable Pt(Ⅳ)nanoprodrug.
文摘Triclosan(TCS) poses harmful risks to ecosystems and human health owing to its endocrine-disrupting effects.Therefore,developing an efficient and sustainable technology to degrade TCS is urgently needed.Herein,cobalt oxyhydroxide @covalent organic frameworks(CoOOH@COFs) S-scheme heterojunction was synthesized,which combined the visible-light-driven photocatalysis and peroxymonosulfate(PMS) activation to synergistically generate abundant reactive oxygen species(ROSs) for TCS degradation.The degradation efficiency of TCS reached 100 % within 8 min in the Vis-CoOOH@COFs/PMS system,and the reaction rate constant was 0.456 min^(-1),which was nearly 1.90 and 2.85 times that of single Co OOH and COFs,and2.36 times that under dark condition,respectively.The density functional theory(DFT) calculations confirmed the energy band bending of CoOOH@COFs and S-scheme charge transport from COFs to Co OOH.Both experimental and theoretical analyses indicated that Co OOH@COFs in photocatalytic-PMS activation systems synergistically facilitated photo-generated carrier separation,enhanced interfacial electron transfer,accelerated PMS activation,and generated multiple ROSs.In particular,photogenerated electrons(e^(-))accelerated the Co(Ⅲ)/Co(Ⅱ) redox cycle,while the PMS captured the e-,which significantly decreased the charge combination of Co OOH@COFs.Radicals(O_(2)^(·-),^(·)OH,and SO_(4)^(·-)) and non-radicals(such as ^(1)O_(2),h^(+),and e^(-)) were both presented in the Vis-CoOOH@COFs/PMS system,with O_(2)^(-) playing a dominant role in TCS degradation.Furthermore,the pathway of TCS degradation and toxicity of intermediates were explored by DFT calculation and transformation product identification.Importantly,the environmentally friendly CoOOH@COFs S-scheme heterojunction exhibited excellent stability and reusability.In conclusion,this study innovatively designed an S-scheme heterojunction in the photocatalytic-PMS activation system,providing guidance and theoretical support for efficient and eco-friendly wastewater treatment.
基金supported by the NIH RF1 grant NS119477 jointly funded by NINDS and NIA(to RM).
文摘Cells of the central nervous system(CNS)are privileged in lying behind the blood-brain barrier(BBB).Unlike blood vessels in other organs,CNS blood vessels are unique in displaying high electrical resistance and low permeability.With this unique structure and function,the BBB prevents potentially harmful blood components such as serum proteins,inflammatory cytokines,and inflammatory leukocytes from entering the hallowed space of the CNS and wreaking havoc.In addition to these“tightness”properties,the BBB has an array of specialized transporters designed to import essential nutrients.
基金supported by the National Natural Science Foundation of China (Grant Nos.T2325004 and 52161160330)the National Natural Science Foundation of China (Grants No.12504233)+2 种基金Advanced MaterialsNational Science and Technology Major Project (Grant No.2024ZD0606900)the Talent Hub for “AI+New Materials” Basic Researchthe Key Research and Development Program of Ningbo (Grant No.2025Z088)。
文摘The functional properties of glasses are governed by their formation history and the complex relaxation processes they undergo.However,under extreme conditions,glass behaviors are still elusive.In this study,we employ simulations with varied protocols to evaluate the effectiveness of different descriptors in predicting mechanical properties across both low-and high-pressure regimes.Our findings demonstrate that conventional structural and configurational descriptors fail to correlate with the mechanical response following pressure release,whereas the activation energy descriptor exhibits robust linearity with shear modulus after correcting for pressure effects.Notably,the soft mode parameter emerges as an ideal and computationally efficient alternative for capturing this mechanical behavior.These findings provide critical insights into the influence of pressure on glassy properties,integrating the distinct features of compressed glasses into a unified theoretical framework.
基金supported by the National Key Research and Development(R&D)Program of China(2022YFB4101600)Key Research and Development(R&D)Projects of Shanxi Province(202102040201003,202202040201007)+1 种基金the Fundamental Research Program of Shanxi Province(20210302123008)the ICC CAS,SCJC-XCL-2023-13,CAS Project for Young Scientists in Basic Research(Grant No.YSBR-102).
文摘Lithium-ion batteries(LIBs)suffer from float charge failure in the grid-scale storage market.However,the lack of a unified descriptor for the diverse reasons behind float charge failure poses a challenge.Here,a quantitative analysis of active lithium loss is conducted across multiple temperatures into float charge of Li(Ni_(0.5)Co_(0.2)Mn_(0.3))O_(2)–graphite batteries.It is proposed that the active lithium loss can be used as a descriptor to describe the reasons for float charge quantitatively.Approximately 6.88%and 0.96%of active lithium are lost due to solid electrolyte interphase thickening and lithium deposition,which are primary and secondary failure reasons,respectively.These findings are confirmed by X-ray photoelectron spectroscopy depth profiling,scanning electron microscope,and accelerating rate calorimeter.Titration-gas chromatography and nuclear magnetic resonance are utilized to quantitatively analyze active lithium loss.Additionally,electrolyte decomposition at high temperatures also contributes to active lithium loss,as determined by Auger electron spectrum and nondestructive ultrasound measurements.Notably,no failure is detected in the cathode due to the relatively low working voltage of the float charge.These findings suggest that inhibiting active lithium loss can be an efficient way of delaying failure during high-temperature float charge processes in LIBs.
基金financially supported by the National Key R&D Program of China(No.2023YFB3812400)the National Natural Science Foundation of China(No.52303370)the Special Fund for the Sci-tech Innovation Strategy of Guangdong Province(No.STKJ202209082)。
文摘The burgeoning growth of the new energy vehicles and aviation industry has escalated the need for energy storage capacitors capable of stable operation in harsh environments.The advent of metal-polyimide complexes has illuminated a novel approach for preparing tem perature-resistant capacitors.However,the general application of these metal-polyimide com plexes is impeded by the high dielectric loss and low breakdown strength,consequences of main-chain coordination and excessive metal ions content.Herein,our study proposes a novel polyimideCu complex material(POP-Cu)predicated on side-chain-type pyridine-Cu coordination,utilizing the structural backbone PMDA-ODA of mature commercial PI(Kapton)with reliable performance.Owing to the high degree of freedom afforded by the side chain with suppressed relaxation activation energy and the long-range electron delocalization formed by d-πcoordination,the dielectric constant of this material containing merely 2.7 mol%Cu increases from 3.25(POPI)to 5.58,while maintaining a remarkably low dielectric loss of 0.0066.Meanwhile,this material exhibits a substantial DC breakdown strength of 436.2 MV·m^(-1)and a high energy density of 5.42 J·cm^(-3),coupled with superior mechanical and thermal properties.Even at 150℃,it retains over 90%of its room-temperature energy density,demon strating notable dielectric stability under high temperatures.These attributes underscore its promising application for capacitors operating in harsh environments.
文摘This study investigated the physicochemical properties,enzyme activities,volatile flavor components,microbial communities,and sensory evaluation of high-temperature Daqu(HTD)during the maturation process,and a standard system was established for comprehensive quality evaluation of HTD.There were obvious changes in the physicochemical properties,enzyme activities,and volatile flavor components at different storage periods,which affected the sensory evaluation of HTD to a certain extent.The results of high-throughput sequencing revealed significant microbial diversity,and showed that the bacterial community changed significantly more than did the fungal community.During the storage process,the dominant bacterial genera were Kroppenstedtia and Thermoascus.The correlation between dominant microorganisms and quality indicators highlighted their role in HTD quality.Lactococcus,Candida,Pichia,Paecilomyces,and protease activity played a crucial role in the formation of isovaleraldehyde.Acidic protease activity had the greatest impact on the microbial community.Moisture promoted isobutyric acid generation.Furthermore,the comprehensive quality evaluation standard system was established by the entropy weight method combined with multi-factor fuzzy mathematics.Consequently,this study provides innovative insights for comprehensive quality evaluation of HTD during storage and establishes a groundwork for scientific and rational storage of HTD and quality control of sauce-flavor Baijiu.
基金National Natural Science Foundation of China(52071126)Natural Science Foundation of Tianjin City,China(22JCQNJC01240)+2 种基金Central Guidance on Local Science and Technology Development Fund of Hebei Province(226Z1009G)Special Funds for Science and Technology Innovation in Hebei(2022X19)Anhui Provincial Natural Science Foundation(2308085ME135)。
文摘Co-based alloy coating was prepared on Zr alloy using laser melting and cladding technique to study the difference in the high-temperature oxidation behavior between pure metal Co coatings and Co-T800 alloy coatings,as well as the wear resistance of the coatings.Besides,the effect of changing the laser melting process on the coatings was also investigated.The oxidation mass gain at 800–1200℃and the high-temperature oxidation behavior during high-temperature treatment for 1 h of two coated Zr alloy samples were studied.Results show that the Co coating and the Co-T800 coating have better resistance against high-temperature oxidation.After oxidizing at 1000℃for 1 h,the thickness of the oxide layer of the uncoated sample was 241.0μm,whereas that of the sample with Co-based coating is only 11.8–35.5μm.The friction wear test shows that the depth of the abrasion mark of the coated sample is only 1/2 of that of the substrate,indicating that the hardness and wear resistance of the Zr substrate are greatly improved.The disadvantage of Co-based coatings is the inferior corrosion resistance in 3.5wt%NaCl solution.
基金financially supported by the National Natural Science Foundation of China(Nos.22102212 and 22479067).
文摘High-nickel ternary cathodes hold a great application prospect in solid-state lithium metal batteries to achieve high-energy density,but they still suffer from structural instability and detrimental side reactions with the solid-state electrolytes.To circumvent these issues,a continuous uniform layer polyacrylonitrile(PAN)was introduced on the surface of LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2) via in situ polymerization of acrylonitrile(AN).Furthermore,the partial-cyclized treatment of PAN(cPAN)coating layer presents high ionic and electron conductivity,which can accelerate interfacial Li+and electron diffusion simultaneously.And the thermodynamically stabilized cPAN coating layer cannot only effectively inhibit detrimental side reactions between cathode and solid-state electrolytes but also provide a homogeneous stress to simultaneously address the problems of bulk structural degradation,which contributes to the exceptional mechanical and electrochemical stabilities of the modified electrode.Besides,the coordination bond interaction between the cPAN and NCM811 can suppress the migration of Ni to elevate the stability of the crystal structure.Benefited from these,the In-cPAN-260@NCM811 shows excellent cycling performance with a retention of 86.8%after 300 cycles and superior rate capability.And endow the solid-state battery with thermal safety stability even at hightemperature extreme environment.This facile and scalable surface engineering represents significant progress in developing high-performance solid-state lithium metal batteries.
基金financially supported by the National Natural Science Foundation of China(Nos.52472032 and 52172023)the Key Program of Natural Science Foundation of Hubei Province(No.2024AFA083)
文摘High-temperature industries,as the primary consumers of energy,are greatly concerned with energy savings.Designing refractory linings with low thermal conductivity to reduce heat dissipation through high-temperature furnace linings is a critical concern.In this study,a series of novel entropy-stabilized spinel materials are reported,and their potential applications in high-temperature industries are investigated.XRD and TEM results indicate that all materials possess a cubic spinel crystal structure with the■space group.Furthermore,these materials exhibit good phase stability at high temperatures.All entropy-stabilized spinel aggregates demonstrated high refractoriness(>1800℃)and a high load softening temperature(>1700℃).The impact of configurational entropy on the properties of entropy-stabilized spinel materials was also studied.As configurational entropy increased,the thermal conductivity of the entropy-stabilized spinel decreased,while slag corrosion resistance deteriorated.For the entropy-stabilized spinel with a configurational entropy value of 1.126R,it showed good high-temperature stability,reliable resistance to slag attack,and a low thermal conductivity of 2.776 W·m^(-1)·K^(-1)at 1000℃.
基金financially supported by the National Natural Science Foundation of China(Nos.52271089 and 52001023)the Basic Research and Application Basic Research Foundation of Guangdong Province(Nos.2022A1515240016 and 2023B1515250006)the Fundamental Research Funds for the Central Universities(No.FRF-BD-23-01).
文摘The austenite(γ)reversely transformed from lath martensite(LM),lath bainite(LB),granular bainite(GB)and pearlite+ferrite(P+F)in a high-strength steel was studied at high temperatures using in-situ electron backscatter diffraction(EBSD).The memory effect of initial γ significantly affects the nucleation of the reverted γ in LM and GB structures,while a weak influence on that of LB and P+F structures.This results in a significant difference in γ grain size after complete austenitization,with the first two obtaining larger γ grains while the latter two are relatively small.Crystallographic analysis revealed that the reverted γ with acicular morphology(γA),most of which maintained the same orientation with the prior γ,dominated the reaustenitization behavior of LM and GB structures through preferential nucleation within γ grains and coalesced growth modes.Although globular reverted γ(γ_(G))with random orientation or large deviation from the prior γ can nucleate at the grain boundaries or within the grains,it is difficult for it to grow and play a role in segmenting and refining the prior γ due to the inhibition of γ_(A) coalescing.For LB and P+F structures,the nucleation rate of intragranular γ_(G) increases with increasing temperature,and always shows a random orientation.These γ_(G) grains can coarsen simultaneously with the intergranular γ_(G),ultimately playing a role in jointly dividing and refining the finalγgrains.Research also found that the differences in the effects of four different microstructures on revertedγnucleation are closely related to the variant selection of the matrix structure,as well as the content and size of cementite(θ).High density of block boundaries induced by weakening of variant selection and many fineθformed in the lath are the key to promoting LB structure to obtain more intragranular γ_(G) formation,as well as the important role of the large-sized θ in P+F structure.
基金supported by the National Natural Science Foundation of China(Grant No.U21B2062)supported by the Key Laboratory for Carbonate Reservoirs of China National Petroleum Corporation。
文摘Burial dissolution is a critical diagenetic process influencing ultra-deep carbonate reservoir development and preservation.Artificial carbonate samples with different internal structures were prepared,and high-temperature and highpressure dissolution kinetic simulations were conducted.The results demonstrate that the intensity of burial dissolution is controlled by temperature and pressure,while tectonic-fluid activity influences the development pattern of burial dissolution,ultimately determining the direction of its differential modification.Extensive burial dissolution is likely to occur primarily at relatively shallow depths,significantly influencing reservoir formation,preservation,modification,and adjustment.The development of faults facilitates the maintenance of the intensity of burial dissolution.The maximum intensity of burial dissolution occurs at the tips and overlap zones of faults and intersections of multiple faults.The larger the scale of the faults,the more conducive it is to the development of burial dissolution.Burial dissolution fosters the formation of fault networks characterized by enhanced reservoir capacity and permeability.Burial dissolution controlled by episodic tectonic-fluid activity is a plausible explanation for forming the Tarim Basin's ultra-deep fault-controlled“stringbead-like”reservoirs.
基金National Key Research and Development Program of China(2023YFB3810200 to J.L.)National Natural Science Foundation of China(92168204,82225030 to J.L.)Fundamental Research Funds for the Central Universities(22120210586 to J.L.)。
文摘Reproductive hormones associated with the hypothalamic-pituitary-gonadal(HPG)axis are closely linked to bone homeostasis.In this study,we demonstrate that Gonadotropin inhibitory hormone(GnIH,one of the key reproductive hormones upstream of the HPG axis)plays an indispensable role in regulating bone homeostasis and maintaining bone mass.We find that deficiency of GnIH or its receptor Gpr147 leads to a significant reduction in bone mineral density(BMD)in mice primarily by enhancement of osteoclast activation in vivo and in vitro.Mechanistically,GnIH/Gpr147 inhibits osteoclastogenesis by the PI3K/AKT,MAPK,NF-κB and Nfatc1 signaling pathways.Furthermore,GnIH treatment was able to alleviate bone loss in aging,ovariectomy(OVX)or LPS-induced mice.Moreover,the therapy using green light promotes the release of GnIH and rescues OVX-induced bone loss.In humans,serum GnIH increases and bone resorption markers decrease after green light exposure.Therefore,our study elucidates that GnIH plays an important role in maintaining bone homeostasis via modulating osteoclast differentiation and demonstrates the potential of GnIH therapy or green light therapy in preventing osteoporosis.
基金supported by the National Key R&D Program of China(No.2022YFB3707700)National Natural Science Foundation of China(No.52302121)+3 种基金Shanghai Sailing Program(No.23YF1454700)Shanghai Natural Science Foundation(No.23ZR1472700)Shanghai Post-doctoral Excellent Program(No.2022664)Shanghai Science and Technology Innovation Action Plan(No.21511104800).
文摘The research on high-performance electromagnetic wave absorption materials with high-temperature and oxidative stability in extreme environments is gaining popularity.Herein,the lightweight silicon carbide nanowires(SiC_(nws))/SiC composites are fabricated with in-situ SiC interface on one-dimensional oriented SiC_(nws)skeleton,which collaborative configuration by 3D printing and freeze casting assembly.The con-structed porous structure optimizes the impedance matching degree and scattering intensity,the maximum effective absorption bandwidth(EAB_(max))of 5.9 GHz and the minimum reflection loss(RL_(min))of−41.4 dB can be realized.Considering the inherent oxidation resistance of SiC,the composites present well-maintained absorption performance at 600℃.Even at 1100℃,the EAB_(max)of 4.9 GHz and RLmin of−30.4 dB also demonstrate the high-temperature absorption stability of the composites,indicating exceptional wave absorption properties and thermal stability.The slight attenuation can be attributed to the decrease in impedance matching capability accompanying the elevated dielectric constant.This work clarifies the impact of structure and component synergy on wave absorption behavior,and offers a novel approach to producing high-performance and high-temperature resistance ceramic-based electromagnetic wave absorption materials suitable for extreme environments.
