With the global oil and gas industry increasingly targeting ultra-deep well development,the demand for wear resistance in polycrystalline diamond compact(PDC)bits is increasing.However,further improvement of the mecha...With the global oil and gas industry increasingly targeting ultra-deep well development,the demand for wear resistance in polycrystalline diamond compact(PDC)bits is increasing.However,further improvement of the mechanical properties of PDC incurs prohibitively elevated costs and stringent technological challenges.Here,we present a two-stage high-pressure infiltration(HPI)methodology involving cobalt removal pretreatment followed by lubricant infiltration.The successful infiltration of lubricants into diamond micropores has been systematically verified,and the effects of lubricant phase composition,infiltration pressure,and temperature on infiltration depth have been thoroughly investigated.Fractal dimension analysis characterizes the pore structure of cobalt-removed diamonds,revealing a strong correlation between the fractal dimension and friction coefficient reduction.Tribological testing confirms the formation of lubricating films at friction interfaces,achieving a 71.5%reduction in the coefficient of friction for lubricant-containing diamond materials.This straightforward strategy opens a gate to developing the next generation of self-lubricating diamond materials.展开更多
Silicon infiltrated silicon carbide （Si-SiC） ceramics, as high hardness materials, are difficult to machine, especially drilling micro-holes. In this study, the interaction of picosecond laser pulses （1 ps at 1 030...Silicon infiltrated silicon carbide （Si-SiC） ceramics, as high hardness materials, are difficult to machine, especially drilling micro-holes. In this study, the interaction of picosecond laser pulses （1 ps at 1 030 nm） with Si-SiC ceramics was investigated. Variations of the diameter and depth of circular holes with the growth of the laser energy density were obtained. The results indicate that the increase of machining depth follows a nonlinear relation with the increasing of laser energy density, while the diameter has little change with that. Moreover, it is found that some debris and particles are deposited around and inside the holes and waviness is in the entrance and at walls of the holes after laser processing.展开更多
The Ni/ZrO2 was used as raw materials to fabricate the surface infiltrated composite layer with 1-4 mm thickness on cast steel substrate through vacuum infiltrated casting technology. The microstructure indicated that...The Ni/ZrO2 was used as raw materials to fabricate the surface infiltrated composite layer with 1-4 mm thickness on cast steel substrate through vacuum infiltrated casting technology. The microstructure indicated that the infiltrated composite layer included surface composite layer and transition layer. Wear property was investigated under room temperature and 450 ~C. The results indicated that the abrasion volume of substrate was 8 times that of the infiltrated composite layer at room temperature. The friction coefficient of infiltrated composite layer decreased with the increasing load. The wear resistance of infiltrated composite layer with different ZrO2 contents had been improved obviously under high temperature. The friction coefficient of infiltrated composite layer was decreased comparing with that at room temperature. The oxidation, abrasive and fatigue abrasion was the main wear mechanism at room temperature. Oxidation abrasion, fatigue wear and adhesive wear dominated the wearin~ process under elevated temperature.展开更多
The B4C/2024Al composites were successfully produced by pressureless infiltration method, and the effects of heat treatment on phase content and mechanical properties were investigated by X-ray diffraction （XRD）, sc...The B4C/2024Al composites were successfully produced by pressureless infiltration method, and the effects of heat treatment on phase content and mechanical properties were investigated by X-ray diffraction （XRD）, scanning electron microscopy （SEM） and mechanical properties testing. The results show that phases of BnC/2024Al composites include B4C, Al, Al3BC, AlB2 and Al2Cu. The phase species remain unchanged; however, the phase content of the composites changes significantly after heat treatment at the temperature of 660, 700, 800 or 900 ℃ for 12, 24 or 36 h. It is found that the heat treatment results in not only considerable enhancement in hardness, but also reduction in bending strength of the composites. Heat treatment at 800 ℃ for 36 h does best to hardness of the composites, while at 700 ℃ for 36 h it is the most beneficial to their comprehensive mechanical properties.展开更多
Diamond reinforced copper （Cu/diamond） composites were prepared by a pressure infilla＇ation technique. The composites show a super high conductivity of 713 W.m-1.K-1 in combination with an extremely low coefficient...Diamond reinforced copper （Cu/diamond） composites were prepared by a pressure infilla＇ation technique. The composites show a super high conductivity of 713 W.m-1.K-1 in combination with an extremely low coefficient of thermal expansion （CTE） of 7.72 × 10-6 K-1 （25-100℃）, which are achieved by modifying the copper matrix with adding 0.3 wt.% of boron to get a good thermal contact between the matrix and the diamond particles. By adopting a series of postmachining techniques the composites were made into near-net-shape parts, and an electroless silver coating was also successfully plated on the composites. Finally, their potential applications in the thermal management of fight emitting diodes （LED） were illustrated via prototype examples.展开更多
Particle erosion of C/C-SiC composites prepared by reactive melt infiltration with different Al addition was studied by gas-entrained solid particle impingement test.SEM,EDS and XRD were performed to analyze the compo...Particle erosion of C/C-SiC composites prepared by reactive melt infiltration with different Al addition was studied by gas-entrained solid particle impingement test.SEM,EDS and XRD were performed to analyze the composites before and after erosion.The results indicate that a U shape relationship curve presents between the erosion rates and Al content,and the lowest erosion rate occurs at 40 wt%Al.Except for the important influence of compactness,the increasing soft Al mixed with reactive SiC,namely the mixture located between carbon and residual Si also,plays a key role in the erosion of the C/C-SiC composites through crack deflection,plastic deformation and bonding cracked Si.展开更多
Thermal properties of AlN-Si-Al composites produced by pressureless melt infiltration of Al/Al alloys into porous a-Si3N4 preforms were investigated in a temperature range of 50-300 °C. SEM and TEM investigations...Thermal properties of AlN-Si-Al composites produced by pressureless melt infiltration of Al/Al alloys into porous a-Si3N4 preforms were investigated in a temperature range of 50-300 °C. SEM and TEM investigations revealed that the grain size of AlN particles was less than 1 μm. In spite of sub-micron grain size, composites showed relatively high thermal conductivity （TC）, 55-107 W/（m·K）. The thermal expansion coefficient （CTE） of the composite produced with commercial Al source, which has the highest TC of 107 W/（m·K）, was 6.5×10-6 K-1. Despite the high CTE of Al （23.6×10-6 K-1）, composites revealed significantly low CTE through the formation of Si and AlN phases during the infiltration process.展开更多
Porous Sr-doped lanthanum manganite–yttria stabilized zirconia(LSM–YSZ)oxygen electrode is prepared by an infiltration process for a reversible solid oxide fuel cell(RSOFC).X-ray diffraction and SEM analysis display...Porous Sr-doped lanthanum manganite–yttria stabilized zirconia(LSM–YSZ)oxygen electrode is prepared by an infiltration process for a reversible solid oxide fuel cell(RSOFC).X-ray diffraction and SEM analysis display that perovskite phase LSM submicro particles are evenly distributed in the porous YSZ matrix.Polarization curves and electrochemical impedance spectra are conducted for the RSOFC at 800 and 850C under both SOFC and SOEC modes.At 850℃,the single cell has the maximum power density of~726 mW/cm^(2)under SOFC mode,and electrolysis voltage of 1.35 V at 1 A/cm^(2)under SOEC mode.Fuel cell/water electrolysis cycle shows the cell has good performance stability during 6 cycles,which exhibits the LSM–YSZ oxygen electrode has high electrochemical performance and good stability.The results suggest that netw ork-like LSM–YSZ electrode made by infiltration process could be a promising oxygen electrode for high temperature RSOFCs.展开更多
This work studies the ionic conductivity of nanosized Gd-, Sm-, and Y-doped ceria prepared by the infiltration/impregnation method. The nanoparticles were deposited onto porous pure ceria substrates via infiltration- ...This work studies the ionic conductivity of nanosized Gd-, Sm-, and Y-doped ceria prepared by the infiltration/impregnation method. The nanoparticles were deposited onto porous pure ceria substrates via infiltration- heating processes, and the conductivity was determined with the electrochemical impedance spectroscopy （EIS） using the conductive model for infiltrated phases. The conductivity of the infiltrated doped ceria changes with the doping amount, and Gd0.25Ce0.75O2-δ, Sm0.2Ce0.8O2-δ, and Y0.15Ce0.85O2-δ show the highest values of 2.56, 3.01, and 2.07 × 10-3 S.cm-1 at 600 ℃, respectively. Overall, Sin-doped samples show the highest conductivity, whileY-doped samples show the lowest conductivity. In con- sideration of the Bruggeman factor, the intrinsic conduc- tivity of the infiltrated doped ceria was calculated. Compared with the bulk doped ceria, the intrinsic con- ductivity is higher while the activation energy is lower, which may suggest different conduction mechanisms. Besides, co-doping effects on the conductivity of the infiltrated sample are less obvious than those of the bulk sample.展开更多
Mixed ionic-electronic conductors in the family of LaxSr1-xCoyFe1-y O3-δ have been widely studied as cathode materials for solid oxide fuel cells （SOFCs）. However, the long-term stability was a concern. Here we rep...Mixed ionic-electronic conductors in the family of LaxSr1-xCoyFe1-y O3-δ have been widely studied as cathode materials for solid oxide fuel cells （SOFCs）. However, the long-term stability was a concern. Here we report our findings on the effect of a thin film coating of La0.85Sr0.15MnO3-δ （LSM） on the performance of a porous La0.6Sr0.4Co0.2Feo.8O3-δ（LSCF） cathode. When the thicknesses of the LSM coatings are appropriate, an LSM-coated LSCF electrode showed better stability and lower polarization （or higher activity） than the blank LSCF cathode without LSM infiltration. An anode-supported cell with an LSM-infiltrated LSCF cathode demonstrated at 825 ℃ a peak power density of -1.07 W/cm2, about 24% higher than that of the same cell without LSM infiltration （-0.86 W/cm2）. Further, the LSM coating enhanced the stability of the electrode; there was little degradation in performance for the cell with an LSM-infiltrated LSCF cathode during 100 h operation.展开更多
Protonic ceramic electrolysis cell(PCEC)is a promising technology for production of pure dry hydrogen due to the low operating temperature and high efficiency.One of the obstacles for commercialization of PCEC technol...Protonic ceramic electrolysis cell(PCEC)is a promising technology for production of pure dry hydrogen due to the low operating temperature and high efficiency.One of the obstacles for commercialization of PCEC technology is the poor performance and insufficient long-term durability of the oxygen electrode.In this study,we address the above challenge by designing a LaCoO_(3)(LC)catalyst infiltrated porous BaZr_(0.8)Y_(0.2)O_(3)−δ(BZY20)backbone electrode(LC-BZY20).The performance and durability of the LC-BZY20 electrode are investigated on symmetrical cells using electrochemical impedance spectroscopy(EIS).The total electrode polarization resistance(RP)values of the electrode are 0.56,1.24,2.18,and 2.90Ωcm2 in 3vol%humidified synthetic air at 600,550,500,and 450℃,respectively,indicating good electrochemical performance of the LC-BZY20 electrode.Furthermore,the LC-BZY20 electrode displays good stability,without significant performance degradation when tested at 600℃ in 10vol%humidified air for 900h.We further study the influence of oxygen partial pressure(PO_(2))and steam partial pressure(P_(H_(2)O))on the response of the EIS data,and propose a set of chemical and electrochemical processes involved in the steam splitting reaction in the LC-BZY20 electrode.展开更多
Post-kidney transplant rejection is a critical factor influencing transplant success rates and the survival of transplanted organs.With the rapid advancement of artificial intelligence technologies,machine learning(ML...Post-kidney transplant rejection is a critical factor influencing transplant success rates and the survival of transplanted organs.With the rapid advancement of artificial intelligence technologies,machine learning(ML)has emerged as a powerful data analysis tool,widely applied in the prediction,diagnosis,and mechanistic study of kidney transplant rejection.This mini-review systematically summarizes the recent applications of ML techniques in post-kidney transplant rejection,covering areas such as the construction of predictive models,identification of biomarkers,analysis of pathological images,assessment of immune cell infiltration,and formulation of personalized treatment strategies.By integrating multi-omics data and clinical information,ML has significantly enhanced the accuracy of early rejection diagnosis and the capability for prognostic evaluation,driving the development of precision medicine in the field of kidney transplantation.Furthermore,this article discusses the challenges faced in existing research and potential future directions,providing a theoretical basis and technical references for related studies.展开更多
Reactive melt infiltration(RMI)is an effective method for fabrication of highly dense carbon fiber reinforced ultra-high temperature ceramic matrix composites(Cf/UHTCs).In this work,C_(f)/SiC-ZrC-ZrB_(2)composites wer...Reactive melt infiltration(RMI)is an effective method for fabrication of highly dense carbon fiber reinforced ultra-high temperature ceramic matrix composites(Cf/UHTCs).In this work,C_(f)/SiC-ZrC-ZrB_(2)composites were fabricated by infiltrating ZrSi_(2)melt into porous C_(f)/B_(4)C-C preforms,where the physical and chemical reactions involved during the RMI process were identified and analyzed.Inhomogeneous infiltration between the inter-and intra-bundle pores was revealed,and was found to be strongly related to the pore structures of the C_(f)/B_(4)C-C preform.It is indicated that the inhomogeneous infiltration can be mitigated remarkably with increasing porosity and pore size of the preform.The effect of pore size on the RMI process was also investigated by a quantitative model,which agrees very well with the experiment results.It further indicates that the inhomogeneous infiltration can also be relieved at elevated RMI temperature.However,excessive infiltration at elevated temperature or more porous preform may cause serious erosion on interphase and fibers,leading to mechanical properties deterioration of the final composites.展开更多
Electrospun fibers,with proven ability to promote tissue regeneration,are widely being explored for rotator cuff repairing.However,without post treatment,the microstructure of the electrospun scaffold is vastly differ...Electrospun fibers,with proven ability to promote tissue regeneration,are widely being explored for rotator cuff repairing.However,without post treatment,the microstructure of the electrospun scaffold is vastly different from that of natural extracellular matrix(ECM).Moreover,during mechanical loading,the nanofibers slip that hampers the proliferation and differentiation of migrating stem cells.Here,electrospun nanofiber scaffolds,with crimped nanofibers and welded joints to biomimic the intricate natural microstructure of tendon-to-bone insertion,were prepared using poly(ester-urethane)urea and gelatin via electrospinning and double crosslinking by a multi-bonding network densification strategy.The crimped nanofiber scaffold(CNS)features bionic tensile stress and induces chondrogenic differentiation,laying credible basis for in vivo experimentation.After repairing a rabbit massive rotator cuff tear using a CNS for 3 months,the continuous translational tendon-to-bone interface was fully regenerated,and fatty infiltration was simultaneously inhibited.Instead of micro-CT,μCT was employed to visualize the integrity and intricateness of the three-dimensional microstructure of the CNS-induced-healed tendon-to-bone interface at an ultra-high resolution of less than 1μm.This study sheds light on the correlation between nanofiber post treatment and massive rotator cuff repair and provides a general strategy for crimped nanofiber preparation and tendon-to-bone interface imaging characterization.展开更多
Aim:Neuroblastoma is the most common extracranial solid tumor in children.Recent advances in immunotherapy Approaches,including in neuroblastoma,have shown the important role of the immune system in mounting an effect...Aim:Neuroblastoma is the most common extracranial solid tumor in children.Recent advances in immunotherapy Approaches,including in neuroblastoma,have shown the important role of the immune system in mounting an effective anti-tumor response.In this study,we aimed to provide a comprehensive investigation of immune cell infiltration in neuroblastoma utilizing a large number of gene expression datasets.Methods:We inferred immune cell infiltration using an established immune inference method and evaluated the association between immune cell abundance and patient prognosis as well as common chromosomal abnormalities found in neuroblastoma.In addition,we evaluated co-infiltration patterns among distinct immune cell types.Results:The infiltration of naïve B cells,NK cells,and CD8+T cells was associated with improved patient prognosis.Naïve B cells were the most consistent indicator of prognosis and associated with an active immune tumor microenvironment.Patients with high B cell infiltration showed high co-infiltration of other immune cell types and the enrichment of immune-related pathways.The presence of high B cell infiltration was associated with both recurrence-free and overall survival,even after adjusting for clinical variables.Conclusion:In this study,we have provided a comprehensive evaluation of immune cell infiltration in neuroblastoma using gene expression data.We propose an important role for B cells in the neuroblastoma tumor microenvironment and suggest that B cells can be used as a prognostic biomarker to predict recurrence-free and overall survival independently of currently utilized prognostic variables.展开更多
Organomegaly is a major component of POEMS syndrome （an acronym of polyneuropathy,organomegaly, endocrinopatfiy, M protein, and-skin changes）, which is a rare multisystem disorder of unknown pathogenesis, In patien...Organomegaly is a major component of POEMS syndrome （an acronym of polyneuropathy,organomegaly, endocrinopatfiy, M protein, and-skin changes）, which is a rare multisystem disorder of unknown pathogenesis, In patients with POEMS syndrome, the organs involved in organomegaly usually are the liver, spleen, and lymph nodes,a-4 Three studies have reported the frequencies of hepatomegaly as 25%, 68%, and 78%; of splenomegaly as 22%, 52%, and 35%;展开更多
BACKGROUND Hepatocellular carcinoma(HCC)is one of the most prevalent and aggressive forms of liver cancer,with high morbidity and poor prognosis due to late diagnosis and limited treatment options.Despite advances in ...BACKGROUND Hepatocellular carcinoma(HCC)is one of the most prevalent and aggressive forms of liver cancer,with high morbidity and poor prognosis due to late diagnosis and limited treatment options.Despite advances in understanding its molecular mechanisms,effective biomarkers for early detection and targeted therapy remain scarce.Zinc finger protein 71(ZNF71),a zinc-finger protein,has been implicated in various cancers,yet its role in HCC remains largely unexplored.This gap in knowledge underscores the need for further investigation into the ZNF71 of potential as a diagnostic or therapeutic target in HCC.AIM To explore the expression levels,clinical relevance,and molecular mechanisms of ZNF71 in the progression of HCC.METHODS The study evaluated ZNF71 expression in 235 HCC specimens and 13 noncancerous liver tissue samples using immunohistochemistry.High-throughput datasets were employed to assess the differential expression of ZNF71 in HCC and its association with clinical and pathological features.The impact of ZNF71 on HCC cell line growth was examined through clustered regularly interspaced short palindromic repeat knockout screens.Co-expressed genes were identified and analyzed for enrichment using LinkedOmics and Sangerbox 3.0,focusing on significant correlations(P<0.01,correlation coefficient≥0.3).Furthermore,the relationship between ZNF71 expression and immune cell infiltration was quantified using TIMER2.0.RESULTS ZNF71 showed higher expression in HCC tissues vs non-tumorous tissues,with a significant statistical difference(P<0.05).Data from the UALCAN platform indicated increased ZNF71 levels across early to mid-stage HCC,correlating with disease severity(P<0.05).High-throughput analysis presented a standardized mean difference in ZNF71 expression of 0.55(95%confidence interval[CI]:0.34-0.75).The efficiency of ZNF71 mRNA was evaluated,yielding an area under the curve of 0.78(95%CI:0.75-0.82),a sensitivity of 0.63(95%CI:0.53-0.72),and a specificity of 0.82(95%CI:0.73-0.89).Diagnostic likelihood ratios were positive at 3.61(95%CI:2.41-5.41)and negative at 0.45(95%CI:0.36-0.56).LinkedOmics analysis identified strong positive correlations of ZNF71 with genes such as ZNF470,ZNF256,and ZNF285.Pathway enrichment analyses highlighted associations with herpes simplex virus type 1 infection,the cell cycle,and DNA replication.Negative correlations involved metabolic pathways,peroxisomes,and fatty acid degradation.TIMER2.0 analysis demonstrated positive correlations of high ZNF71 expression with various immune cell types,including CD4^(+)T cells,B cells,regulatory T cells,monocytes,macrophages,and myeloid dendritic cells.CONCLUSION ZNF71 is significantly upregulated in HCC,correlating with the disease’s clinical and pathological stages.It appears to promote HCC progression through mechanisms involving the cell cycle and metabolism and is associated with immune cell infiltration.These findings suggest that ZNF71 could be a novel target for diagnosing and treating HCC.展开更多
基金supported by the National Natural Science Foundation of China(grant number:52203375 and 52073254)。
文摘With the global oil and gas industry increasingly targeting ultra-deep well development,the demand for wear resistance in polycrystalline diamond compact(PDC)bits is increasing.However,further improvement of the mechanical properties of PDC incurs prohibitively elevated costs and stringent technological challenges.Here,we present a two-stage high-pressure infiltration(HPI)methodology involving cobalt removal pretreatment followed by lubricant infiltration.The successful infiltration of lubricants into diamond micropores has been systematically verified,and the effects of lubricant phase composition,infiltration pressure,and temperature on infiltration depth have been thoroughly investigated.Fractal dimension analysis characterizes the pore structure of cobalt-removed diamonds,revealing a strong correlation between the fractal dimension and friction coefficient reduction.Tribological testing confirms the formation of lubricating films at friction interfaces,achieving a 71.5%reduction in the coefficient of friction for lubricant-containing diamond materials.This straightforward strategy opens a gate to developing the next generation of self-lubricating diamond materials.
基金Funded by National Natural Science Foundation of China(Nos.51332004,51302220,51472201)the Major National Scientific Instrument and Equipment Development Project(No.2011YQ12007504)+1 种基金Natural Science Foundation of Shaanxi Province(No.2014JQ6197)the Foundation Research of Northwestern Polytechnical University(No.JC20120204)
文摘Silicon infiltrated silicon carbide （Si-SiC） ceramics, as high hardness materials, are difficult to machine, especially drilling micro-holes. In this study, the interaction of picosecond laser pulses （1 ps at 1 030 nm） with Si-SiC ceramics was investigated. Variations of the diameter and depth of circular holes with the growth of the laser energy density were obtained. The results indicate that the increase of machining depth follows a nonlinear relation with the increasing of laser energy density, while the diameter has little change with that. Moreover, it is found that some debris and particles are deposited around and inside the holes and waviness is in the entrance and at walls of the holes after laser processing.
基金"Xi-Bu-Zhi-Guang" Foundation of Chinese Academy of Sciences(No.XBZG-2007-5)Gansu Natural Science Foundation of China(No.0806RJYA004)
文摘The Ni/ZrO2 was used as raw materials to fabricate the surface infiltrated composite layer with 1-4 mm thickness on cast steel substrate through vacuum infiltrated casting technology. The microstructure indicated that the infiltrated composite layer included surface composite layer and transition layer. Wear property was investigated under room temperature and 450 ~C. The results indicated that the abrasion volume of substrate was 8 times that of the infiltrated composite layer at room temperature. The friction coefficient of infiltrated composite layer decreased with the increasing load. The wear resistance of infiltrated composite layer with different ZrO2 contents had been improved obviously under high temperature. The friction coefficient of infiltrated composite layer was decreased comparing with that at room temperature. The oxidation, abrasive and fatigue abrasion was the main wear mechanism at room temperature. Oxidation abrasion, fatigue wear and adhesive wear dominated the wearin~ process under elevated temperature.
基金Project(2011CB605805)supported by the National Basic Research Program of China
文摘The B4C/2024Al composites were successfully produced by pressureless infiltration method, and the effects of heat treatment on phase content and mechanical properties were investigated by X-ray diffraction （XRD）, scanning electron microscopy （SEM） and mechanical properties testing. The results show that phases of BnC/2024Al composites include B4C, Al, Al3BC, AlB2 and Al2Cu. The phase species remain unchanged; however, the phase content of the composites changes significantly after heat treatment at the temperature of 660, 700, 800 or 900 ℃ for 12, 24 or 36 h. It is found that the heat treatment results in not only considerable enhancement in hardness, but also reduction in bending strength of the composites. Heat treatment at 800 ℃ for 36 h does best to hardness of the composites, while at 700 ℃ for 36 h it is the most beneficial to their comprehensive mechanical properties.
基金supported by the National Natural Science Foundation of China (No. 50971020)the National High-Tech Research and Development Program of China (No. 2008AA03Z505)
文摘Diamond reinforced copper （Cu/diamond） composites were prepared by a pressure infilla＇ation technique. The composites show a super high conductivity of 713 W.m-1.K-1 in combination with an extremely low coefficient of thermal expansion （CTE） of 7.72 × 10-6 K-1 （25-100℃）, which are achieved by modifying the copper matrix with adding 0.3 wt.% of boron to get a good thermal contact between the matrix and the diamond particles. By adopting a series of postmachining techniques the composites were made into near-net-shape parts, and an electroless silver coating was also successfully plated on the composites. Finally, their potential applications in the thermal management of fight emitting diodes （LED） were illustrated via prototype examples.
基金Project(51902239)supported by the National Natural Science Foundation of ChinaProject(2020JQ-808)supported by the Science and Technology Fund of Shaanxi Province,China+3 种基金Projects(19JK0400,19JK0402)supported by the Education Fund of Shaanxi Province,ChinaProject(SKLSP201752)supported by the State Key Laboratory of Solidification Processing in Northwestern Poly Technical University,ChinaProject(XAGDXJJ17008)supported by the Principal Fund of Xi’an Technological University,ChinaProject supported by the Youth Innovation Team of Shaanxi Universities,China。
文摘Particle erosion of C/C-SiC composites prepared by reactive melt infiltration with different Al addition was studied by gas-entrained solid particle impingement test.SEM,EDS and XRD were performed to analyze the composites before and after erosion.The results indicate that a U shape relationship curve presents between the erosion rates and Al content,and the lowest erosion rate occurs at 40 wt%Al.Except for the important influence of compactness,the increasing soft Al mixed with reactive SiC,namely the mixture located between carbon and residual Si also,plays a key role in the erosion of the C/C-SiC composites through crack deflection,plastic deformation and bonding cracked Si.
基金The Foundation for Scientific Research Projects of Mugla Sitki Kocman University(Project No.10/30)The Scientific&Technological Research Council of Turkey(TUBITAK,Project No:108M194)for funding the present work
文摘Thermal properties of AlN-Si-Al composites produced by pressureless melt infiltration of Al/Al alloys into porous a-Si3N4 preforms were investigated in a temperature range of 50-300 °C. SEM and TEM investigations revealed that the grain size of AlN particles was less than 1 μm. In spite of sub-micron grain size, composites showed relatively high thermal conductivity （TC）, 55-107 W/（m·K）. The thermal expansion coefficient （CTE） of the composite produced with commercial Al source, which has the highest TC of 107 W/（m·K）, was 6.5×10-6 K-1. Despite the high CTE of Al （23.6×10-6 K-1）, composites revealed significantly low CTE through the formation of Si and AlN phases during the infiltration process.
基金This project was sponsored by financial supports from the Major State Basic Research Development Program of China(973 Program,No.2012CB215406).
文摘Porous Sr-doped lanthanum manganite–yttria stabilized zirconia(LSM–YSZ)oxygen electrode is prepared by an infiltration process for a reversible solid oxide fuel cell(RSOFC).X-ray diffraction and SEM analysis display that perovskite phase LSM submicro particles are evenly distributed in the porous YSZ matrix.Polarization curves and electrochemical impedance spectra are conducted for the RSOFC at 800 and 850C under both SOFC and SOEC modes.At 850℃,the single cell has the maximum power density of~726 mW/cm^(2)under SOFC mode,and electrolysis voltage of 1.35 V at 1 A/cm^(2)under SOEC mode.Fuel cell/water electrolysis cycle shows the cell has good performance stability during 6 cycles,which exhibits the LSM–YSZ oxygen electrode has high electrochemical performance and good stability.The results suggest that netw ork-like LSM–YSZ electrode made by infiltration process could be a promising oxygen electrode for high temperature RSOFCs.
基金financially supported by the China Postdoctoral Science Foundation-Chinese Academy of Sciences(CPSF-CAS)Joint Foundation for Excellent Postdoctoral Fellowsthe National Natural Science Foundation for Distinguished Young Scholars of China (No.51625204)the National Nature Science Foundation of China (91645101)
文摘This work studies the ionic conductivity of nanosized Gd-, Sm-, and Y-doped ceria prepared by the infiltration/impregnation method. The nanoparticles were deposited onto porous pure ceria substrates via infiltration- heating processes, and the conductivity was determined with the electrochemical impedance spectroscopy （EIS） using the conductive model for infiltrated phases. The conductivity of the infiltrated doped ceria changes with the doping amount, and Gd0.25Ce0.75O2-δ, Sm0.2Ce0.8O2-δ, and Y0.15Ce0.85O2-δ show the highest values of 2.56, 3.01, and 2.07 × 10-3 S.cm-1 at 600 ℃, respectively. Overall, Sin-doped samples show the highest conductivity, whileY-doped samples show the lowest conductivity. In con- sideration of the Bruggeman factor, the intrinsic conduc- tivity of the infiltrated doped ceria was calculated. Compared with the bulk doped ceria, the intrinsic con- ductivity is higher while the activation energy is lower, which may suggest different conduction mechanisms. Besides, co-doping effects on the conductivity of the infiltrated sample are less obvious than those of the bulk sample.
基金supported by the Department of Energy (National Energy Technology Laboratory) SECA Core Technology Program under Award Number DE-NT0006557 and DE-FE0009652by NSFC under grant No.51002182
文摘Mixed ionic-electronic conductors in the family of LaxSr1-xCoyFe1-y O3-δ have been widely studied as cathode materials for solid oxide fuel cells （SOFCs）. However, the long-term stability was a concern. Here we report our findings on the effect of a thin film coating of La0.85Sr0.15MnO3-δ （LSM） on the performance of a porous La0.6Sr0.4Co0.2Feo.8O3-δ（LSCF） cathode. When the thicknesses of the LSM coatings are appropriate, an LSM-coated LSCF electrode showed better stability and lower polarization （or higher activity） than the blank LSCF cathode without LSM infiltration. An anode-supported cell with an LSM-infiltrated LSCF cathode demonstrated at 825 ℃ a peak power density of -1.07 W/cm2, about 24% higher than that of the same cell without LSM infiltration （-0.86 W/cm2）. Further, the LSM coating enhanced the stability of the electrode; there was little degradation in performance for the cell with an LSM-infiltrated LSCF cathode during 100 h operation.
基金support from the China Scholarship Council(CSC201807040049)from DTU Energy.The authors would like to thank H.Henriksen for his help with cell testing.
文摘Protonic ceramic electrolysis cell(PCEC)is a promising technology for production of pure dry hydrogen due to the low operating temperature and high efficiency.One of the obstacles for commercialization of PCEC technology is the poor performance and insufficient long-term durability of the oxygen electrode.In this study,we address the above challenge by designing a LaCoO_(3)(LC)catalyst infiltrated porous BaZr_(0.8)Y_(0.2)O_(3)−δ(BZY20)backbone electrode(LC-BZY20).The performance and durability of the LC-BZY20 electrode are investigated on symmetrical cells using electrochemical impedance spectroscopy(EIS).The total electrode polarization resistance(RP)values of the electrode are 0.56,1.24,2.18,and 2.90Ωcm2 in 3vol%humidified synthetic air at 600,550,500,and 450℃,respectively,indicating good electrochemical performance of the LC-BZY20 electrode.Furthermore,the LC-BZY20 electrode displays good stability,without significant performance degradation when tested at 600℃ in 10vol%humidified air for 900h.We further study the influence of oxygen partial pressure(PO_(2))and steam partial pressure(P_(H_(2)O))on the response of the EIS data,and propose a set of chemical and electrochemical processes involved in the steam splitting reaction in the LC-BZY20 electrode.
文摘Post-kidney transplant rejection is a critical factor influencing transplant success rates and the survival of transplanted organs.With the rapid advancement of artificial intelligence technologies,machine learning(ML)has emerged as a powerful data analysis tool,widely applied in the prediction,diagnosis,and mechanistic study of kidney transplant rejection.This mini-review systematically summarizes the recent applications of ML techniques in post-kidney transplant rejection,covering areas such as the construction of predictive models,identification of biomarkers,analysis of pathological images,assessment of immune cell infiltration,and formulation of personalized treatment strategies.By integrating multi-omics data and clinical information,ML has significantly enhanced the accuracy of early rejection diagnosis and the capability for prognostic evaluation,driving the development of precision medicine in the field of kidney transplantation.Furthermore,this article discusses the challenges faced in existing research and potential future directions,providing a theoretical basis and technical references for related studies.
基金The financial support from“The National Key Research and Development Program of China”(No.2017YFB0703200)“National Natural Science Foundation of China”(No.51702341)+1 种基金Chinese Academy of Sciences Innovative Funding(CXJJ-17-M169)“CAS Pioneer Hundred Talents Program”are greatly acknowledged.
文摘Reactive melt infiltration(RMI)is an effective method for fabrication of highly dense carbon fiber reinforced ultra-high temperature ceramic matrix composites(Cf/UHTCs).In this work,C_(f)/SiC-ZrC-ZrB_(2)composites were fabricated by infiltrating ZrSi_(2)melt into porous C_(f)/B_(4)C-C preforms,where the physical and chemical reactions involved during the RMI process were identified and analyzed.Inhomogeneous infiltration between the inter-and intra-bundle pores was revealed,and was found to be strongly related to the pore structures of the C_(f)/B_(4)C-C preform.It is indicated that the inhomogeneous infiltration can be mitigated remarkably with increasing porosity and pore size of the preform.The effect of pore size on the RMI process was also investigated by a quantitative model,which agrees very well with the experiment results.It further indicates that the inhomogeneous infiltration can also be relieved at elevated RMI temperature.However,excessive infiltration at elevated temperature or more porous preform may cause serious erosion on interphase and fibers,leading to mechanical properties deterioration of the final composites.
基金supported by Instrumental Analysis Center of Shanghai Jiao Tong University.This work was supported by the National Natural Science Foundation of China[Grant No.81902186,81671920,31972923,81871753,81772341]National Key Research and Development Program of China[Grant No.2018YFC1106200,2018YFC1106201,2018YFC1106202]Technology Support Project of Science and Technology Commission of Shanghai Municipality of China[Grant No.19441901700,19441901701,19441901702,18441902800].
文摘Electrospun fibers,with proven ability to promote tissue regeneration,are widely being explored for rotator cuff repairing.However,without post treatment,the microstructure of the electrospun scaffold is vastly different from that of natural extracellular matrix(ECM).Moreover,during mechanical loading,the nanofibers slip that hampers the proliferation and differentiation of migrating stem cells.Here,electrospun nanofiber scaffolds,with crimped nanofibers and welded joints to biomimic the intricate natural microstructure of tendon-to-bone insertion,were prepared using poly(ester-urethane)urea and gelatin via electrospinning and double crosslinking by a multi-bonding network densification strategy.The crimped nanofiber scaffold(CNS)features bionic tensile stress and induces chondrogenic differentiation,laying credible basis for in vivo experimentation.After repairing a rabbit massive rotator cuff tear using a CNS for 3 months,the continuous translational tendon-to-bone interface was fully regenerated,and fatty infiltration was simultaneously inhibited.Instead of micro-CT,μCT was employed to visualize the integrity and intricateness of the three-dimensional microstructure of the CNS-induced-healed tendon-to-bone interface at an ultra-high resolution of less than 1μm.This study sheds light on the correlation between nanofiber post treatment and massive rotator cuff repair and provides a general strategy for crimped nanofiber preparation and tendon-to-bone interface imaging characterization.
基金supported by the Cancer Prevention Research Institute of Texas(CPRIT)(RR180061 to Cheng C)the National Cancer Institute of the National Institutes of Health(1R21CA227996 to Cheng C)the T32 training grant of the National Institutes of Health(T32 AI007363 to Schaafsma E).Cheng C is a CPRIT Scholar in Cancer Research.
文摘Aim:Neuroblastoma is the most common extracranial solid tumor in children.Recent advances in immunotherapy Approaches,including in neuroblastoma,have shown the important role of the immune system in mounting an effective anti-tumor response.In this study,we aimed to provide a comprehensive investigation of immune cell infiltration in neuroblastoma utilizing a large number of gene expression datasets.Methods:We inferred immune cell infiltration using an established immune inference method and evaluated the association between immune cell abundance and patient prognosis as well as common chromosomal abnormalities found in neuroblastoma.In addition,we evaluated co-infiltration patterns among distinct immune cell types.Results:The infiltration of naïve B cells,NK cells,and CD8+T cells was associated with improved patient prognosis.Naïve B cells were the most consistent indicator of prognosis and associated with an active immune tumor microenvironment.Patients with high B cell infiltration showed high co-infiltration of other immune cell types and the enrichment of immune-related pathways.The presence of high B cell infiltration was associated with both recurrence-free and overall survival,even after adjusting for clinical variables.Conclusion:In this study,we have provided a comprehensive evaluation of immune cell infiltration in neuroblastoma using gene expression data.We propose an important role for B cells in the neuroblastoma tumor microenvironment and suggest that B cells can be used as a prognostic biomarker to predict recurrence-free and overall survival independently of currently utilized prognostic variables.
文摘Organomegaly is a major component of POEMS syndrome （an acronym of polyneuropathy,organomegaly, endocrinopatfiy, M protein, and-skin changes）, which is a rare multisystem disorder of unknown pathogenesis, In patients with POEMS syndrome, the organs involved in organomegaly usually are the liver, spleen, and lymph nodes,a-4 Three studies have reported the frequencies of hepatomegaly as 25%, 68%, and 78%; of splenomegaly as 22%, 52%, and 35%;
基金Supported by Joint Project on Regional High Incidence Diseases Research of Guangxi Natural Science Foundation,No.2024GXNSFAA010057 and No.2024GXNSFAA010085Natural Science Foundation of Guangxi,China,No.2022GXNSFBA035657+2 种基金Guangxi Zhuang Autonomous Region Health Commission Self-Financed Scientific Research Project,No.Z20210764Guangxi Zhuang Autonomous Region Administration of Traditional Chinese Medicine Scientific Research Project,No.GXZYA20230270 and No.GXZYA20240305Advanced Innovation Teams and Xinghu Scholars Program of Guangxi Medical University(2022).
文摘BACKGROUND Hepatocellular carcinoma(HCC)is one of the most prevalent and aggressive forms of liver cancer,with high morbidity and poor prognosis due to late diagnosis and limited treatment options.Despite advances in understanding its molecular mechanisms,effective biomarkers for early detection and targeted therapy remain scarce.Zinc finger protein 71(ZNF71),a zinc-finger protein,has been implicated in various cancers,yet its role in HCC remains largely unexplored.This gap in knowledge underscores the need for further investigation into the ZNF71 of potential as a diagnostic or therapeutic target in HCC.AIM To explore the expression levels,clinical relevance,and molecular mechanisms of ZNF71 in the progression of HCC.METHODS The study evaluated ZNF71 expression in 235 HCC specimens and 13 noncancerous liver tissue samples using immunohistochemistry.High-throughput datasets were employed to assess the differential expression of ZNF71 in HCC and its association with clinical and pathological features.The impact of ZNF71 on HCC cell line growth was examined through clustered regularly interspaced short palindromic repeat knockout screens.Co-expressed genes were identified and analyzed for enrichment using LinkedOmics and Sangerbox 3.0,focusing on significant correlations(P<0.01,correlation coefficient≥0.3).Furthermore,the relationship between ZNF71 expression and immune cell infiltration was quantified using TIMER2.0.RESULTS ZNF71 showed higher expression in HCC tissues vs non-tumorous tissues,with a significant statistical difference(P<0.05).Data from the UALCAN platform indicated increased ZNF71 levels across early to mid-stage HCC,correlating with disease severity(P<0.05).High-throughput analysis presented a standardized mean difference in ZNF71 expression of 0.55(95%confidence interval[CI]:0.34-0.75).The efficiency of ZNF71 mRNA was evaluated,yielding an area under the curve of 0.78(95%CI:0.75-0.82),a sensitivity of 0.63(95%CI:0.53-0.72),and a specificity of 0.82(95%CI:0.73-0.89).Diagnostic likelihood ratios were positive at 3.61(95%CI:2.41-5.41)and negative at 0.45(95%CI:0.36-0.56).LinkedOmics analysis identified strong positive correlations of ZNF71 with genes such as ZNF470,ZNF256,and ZNF285.Pathway enrichment analyses highlighted associations with herpes simplex virus type 1 infection,the cell cycle,and DNA replication.Negative correlations involved metabolic pathways,peroxisomes,and fatty acid degradation.TIMER2.0 analysis demonstrated positive correlations of high ZNF71 expression with various immune cell types,including CD4^(+)T cells,B cells,regulatory T cells,monocytes,macrophages,and myeloid dendritic cells.CONCLUSION ZNF71 is significantly upregulated in HCC,correlating with the disease’s clinical and pathological stages.It appears to promote HCC progression through mechanisms involving the cell cycle and metabolism and is associated with immune cell infiltration.These findings suggest that ZNF71 could be a novel target for diagnosing and treating HCC.
