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
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
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
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
Background:Heat shock protein B8(HSPB8)is implicated in autophagy,and its aberrant expression has been linked to both the ini-tiation and progression of tumors.However,the role and function of HSPB8 in colorectal canc...Background:Heat shock protein B8(HSPB8)is implicated in autophagy,and its aberrant expression has been linked to both the ini-tiation and progression of tumors.However,the role and function of HSPB8 in colorectal cancer(CRC)and across multiple cancer types remain unclear.This study aimed to map the transcriptome of autophagy-related genes in CRC and to conduct a pan-cancer analysis of HSPB8 as both a prognostic and immunological biomarker.Methods:We performed bioinformatics analyses on GSE113513 and GSE74602 to identify differentially expressed genes(DEGs)in CRC.These DEGs were then compared with autophagy-related genes to identify critical overlapping genes.The Kaplan-Meier plotter was used to verify the ex-pression of autophagy-linked DEGs and evaluate its prognostic value.The protein expression of Hub gene in CRC was analyzed using the Human Protein Atlas database.The cBioPortal was used to analyze the type and frequency of Hub gene mutations.The TIMER(Tumor Immune Estimation Resource)database was used to study the correlation between HSPB8 and immune infiltration in CRC.Results:In total,825 DEGs were identified,including 8 autophagy-linked DEGs:ATIC,MYC,HSPB8,TNFSF10,BCL2,TP53INP2,ITPR1,and NKX2-3.Survival analysis showed that increased HSPB8 expression significantly correlates with poor prognosis in patients with CRC(p<0.05).HSPB8 was also found to be differentially expressed in various cancer types,correlating with both prognosis and immune infiltration.Further,changes in HSPB8 methylation and phosphorylation status were observed across several cancers,suggesting potential regulatory mechanisms.Therefore,HSPB8 may serve as a crucial prognostic and immunological biomarker in CRC and other cancers.Conclusions:This study provides new insights into the role of autophagy-related genes in cancer progression and highlights HSPB8 as a potential target for cancer diagnostics and therapy.展开更多
To effectively regulate the grain boundary infiltration in CoCrFeMnNi high-entropy alloy(Cantor alloys,HEA)caused by the violent atomic interdiffusion,the higher configuration entropy on Cantor alloys surface was desi...To effectively regulate the grain boundary infiltration in CoCrFeMnNi high-entropy alloy(Cantor alloys,HEA)caused by the violent atomic interdiffusion,the higher configuration entropy on Cantor alloys surface was designed and realized via eutectic high-entropy(EHEA)transformation.Meanwhile,to effectively alleviate the residual stress caused by the notable difference in the thermal expansion coefficient(CTE)between Cantor alloys and Zr-3 alloys,a cladding layer was applied to the HEA surface using laser cladding technology of Nb,followed by brazing to Zr-3 alloys with Zr63.2Cu filler.The cladding layer’s microstructure comprised Nbss and FCC+(Co,Ni)_(2) Nb eutectic structure,resulting from an in-situ reaction between Cantor alloys and Nb.The Nbss and FCC demonstrated good plasticity,and the(Co,Ni)_(2) Nb Laves phase provided increased strength,endowing both good plastic deformation ability and strength of the cladding layer.Notably,the existence of EHEA in the laser cladding layer made the Cantor alloy entropy from 1.61 R to 1.77 R,greatly enhancing its thermal stability and suppressing the grave grain boundary infiltration.Joints produced via laser cladding with Nb-assisted brazing exhibited a complex microstructure(HEA/Nbss+FCC+(Co,Ni)_(2)Nb/(Zr,Nb)(Cr,Mn)_(2)+(Zr,Nb)ss/(Zr,Nb)_(2)(Cu,Ni,Co,Fe)+(Zr,Nb)(Cr,Mn)_(2)+(Zr,Nb)ss/Zr-3) and a significantly improved shear strength of 242.8 MPa at 1010℃ for 10 min,42.4%higher than that of directly brazed joints.This improvement was attributed to reduced grain boundary infiltration,alleviated residual stress due to CTE disparity,and eliminated micro-cracks in the brazing seam.This study presents an effective solution for reducing residual stresses and achieving reliable bonding between Cantor alloys and Zr-3 alloys,with potential applications in brazing CoCrFeNi-based HEA and Zr-3 due to the beneficial eutectic reaction between CoCrFeNi and Nb.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
Background:Cisplatin(DDP)has been used in the treatment of various human cancers.However,DDP alone lacks efficacy in treating triple-negative breast cancer(TNBC),and its clinical application is often hampered by side ...Background:Cisplatin(DDP)has been used in the treatment of various human cancers.However,DDP alone lacks efficacy in treating triple-negative breast cancer(TNBC),and its clinical application is often hampered by side effects.Astragalus polysaccharide(APS)is one of the active components extracted from Astragalus membranaceus and has gained attention for its various biological properties.This research is aimed to evaluate the effectiveness of a combination of APS and DDP on TNBC and explore the potential mechanisms.Methods:The efficacy and mechanisms of single or combined treatment were evaluated using Cell Counting Kit-8(CCK8)assay,Annexin V-fluorescein isothiocyanate(FITC)/propidium iodide(PI)staining,wound healing assay,trans-well invasion/migration assay,hematoxylin-eosin(HE)staining,immunohistochemical(IHC)staining,Western Blot(WB)analysis,and fluorescence-activated cell sorting(FACS).An orthotopic model of TNBC was used to assess the in vivo treatment efficacy of single or combination treatment.Results:APS significantly enhanced the anti-proliferative,anti-migratory,and anti-invasive effects of DDP on TNBC cells.The combination of APS and DDP downregulated anti-apoptotic genes(Bcl2 and Bcl-xL)while upregulating pro-apoptotic genes(Puma,Cle-Caspase3,Cle-PARP),leading to enhanced apoptosis.This combination treatment increased E-cadherin levels,decreased Vimentin,Snail,Slug,and Twist levels,and effectively suppressed epithelial-mesenchymal transition(EMT)-associated cell invasion.In the orthotopic model of TNBC,a synergistic reduction in tumor growth was observed in mice treated with APS and DDP.Additionally,the combination of APS and DDP induced the infiltration of CD8+T lymphocytes into the tumor immune microenvironment.Conclusion:The combination of APS and DDP exhibits more potent tumor inhibition and anti-tumor immunity than either agent alone,representing a novel approach to enhance therapeutic efficacy without increasing the side effects of DDP.展开更多
Background:NDC80 is pivotal in cell division,particularly in regulating the G2/M transition and mitotic progression.Recent studies have demonstrated that NDC80 is significantly overexpressed in multiple solid tumors.F...Background:NDC80 is pivotal in cell division,particularly in regulating the G2/M transition and mitotic progression.Recent studies have demonstrated that NDC80 is significantly overexpressed in multiple solid tumors.Further analysis has suggested that its high expression is significantly associated with an elevated pathological grade,increased metastatic risk,and shortened overall survival in patients with cancer.However,its precise role in pan-cancer development,progression,and prognosis remains unclear.Methods:We conducted a multi-omics analysis of NDC80 using genomic,transcriptomic,and proteomic data from 33 cancer types in The Cancer Genome Atlas,Clinical Proteomic Tumor Analysis Consortium,Genotype-Tissue Expression,and Human Protein Atlas.Results:The results demonstrated frequent NDC80 mutations across multiple malignancies and significantly elevated expression in tumor tissues compared with that in their normal counterparts,correlating with worse overall and disease-free survival.Moreover,NDC80 expression was strongly associated with oncogenic pathways,key protein regulators,cellular components,myeloid-derived suppressor cell infiltration,ESTIMATE scores,and cancer-related signaling networks.Conclusions:These findings underscore the potential of NDC80 as a prognostic biomarker and therapeutic target for cancer treatment.展开更多
To the Editor:Pancreatic cancer is a malignancy characterized by a poor prog-nosis,with a 5-year survival rate of<10%[1].Furthermore,only a minority of patients(<20%)qualify for curative-intent resec-tion,and ev...To the Editor:Pancreatic cancer is a malignancy characterized by a poor prog-nosis,with a 5-year survival rate of<10%[1].Furthermore,only a minority of patients(<20%)qualify for curative-intent resec-tion,and even among those who undergo this procedure,the risk of recurrence within three years remains alarmingly high,reach-ing up to 70%[2].Due to the lack of specific clinical manifes-tations of pancreatic cancer,most cases have metastasized or in-vaded the major vessels around the pancreas at the time of initial diagnosis,resulting in a low surgical resection rate.Even patients who undergo surgical resection often face a poor prognosis[3].In recent years,neoadjuvant chemotherapy using agents such as gemcitabine,5-fluorouracil,albumin-bound paclitaxel,modified fluorouracil/leucovorin plus irinotecan,and oxaliplatin(mFOLFIRI-NOX),targeted therapies addressing molecular subtypes of pan-creatic cancer,and immunotherapies targeting PD-1 and PD-L1 have shown efficacy in improving the overall prognosis of patients with pancreatic cancer,although the impact remains modest[4,5].Therefore,novel therapeutic strategies and prognostic evaluation systems are urgently needed to enhance the survival of patients with pancreatic cancer.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.
基金supported by the NationalNatural Science Foundation of China(no.32360888)the Jiangxi Students’Platform for Innovation and Entrepreneurship Training Program(no.202411843023).
文摘Background:Heat shock protein B8(HSPB8)is implicated in autophagy,and its aberrant expression has been linked to both the ini-tiation and progression of tumors.However,the role and function of HSPB8 in colorectal cancer(CRC)and across multiple cancer types remain unclear.This study aimed to map the transcriptome of autophagy-related genes in CRC and to conduct a pan-cancer analysis of HSPB8 as both a prognostic and immunological biomarker.Methods:We performed bioinformatics analyses on GSE113513 and GSE74602 to identify differentially expressed genes(DEGs)in CRC.These DEGs were then compared with autophagy-related genes to identify critical overlapping genes.The Kaplan-Meier plotter was used to verify the ex-pression of autophagy-linked DEGs and evaluate its prognostic value.The protein expression of Hub gene in CRC was analyzed using the Human Protein Atlas database.The cBioPortal was used to analyze the type and frequency of Hub gene mutations.The TIMER(Tumor Immune Estimation Resource)database was used to study the correlation between HSPB8 and immune infiltration in CRC.Results:In total,825 DEGs were identified,including 8 autophagy-linked DEGs:ATIC,MYC,HSPB8,TNFSF10,BCL2,TP53INP2,ITPR1,and NKX2-3.Survival analysis showed that increased HSPB8 expression significantly correlates with poor prognosis in patients with CRC(p<0.05).HSPB8 was also found to be differentially expressed in various cancer types,correlating with both prognosis and immune infiltration.Further,changes in HSPB8 methylation and phosphorylation status were observed across several cancers,suggesting potential regulatory mechanisms.Therefore,HSPB8 may serve as a crucial prognostic and immunological biomarker in CRC and other cancers.Conclusions:This study provides new insights into the role of autophagy-related genes in cancer progression and highlights HSPB8 as a potential target for cancer diagnostics and therapy.
基金supported by the National Natural Science Foundation of China(Grant Nos.52275321 and 52205348)the Shandong Natural Science Foundation(Grant No.ZR2023JQ021)+3 种基金the Taishan Scholars Foundation of Shandong Province(No.tsqn 201812128)the Innovation Scientists and Technicians Troop Projects of Henan Province(No.204200510031)the Heilongjiang Touyan Innovation Team Program(No.HITTY-20190013)supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIP)(Nos.NRF-2021R1A2C3006662 and NRF-2022R1A5A1030054).
文摘To effectively regulate the grain boundary infiltration in CoCrFeMnNi high-entropy alloy(Cantor alloys,HEA)caused by the violent atomic interdiffusion,the higher configuration entropy on Cantor alloys surface was designed and realized via eutectic high-entropy(EHEA)transformation.Meanwhile,to effectively alleviate the residual stress caused by the notable difference in the thermal expansion coefficient(CTE)between Cantor alloys and Zr-3 alloys,a cladding layer was applied to the HEA surface using laser cladding technology of Nb,followed by brazing to Zr-3 alloys with Zr63.2Cu filler.The cladding layer’s microstructure comprised Nbss and FCC+(Co,Ni)_(2) Nb eutectic structure,resulting from an in-situ reaction between Cantor alloys and Nb.The Nbss and FCC demonstrated good plasticity,and the(Co,Ni)_(2) Nb Laves phase provided increased strength,endowing both good plastic deformation ability and strength of the cladding layer.Notably,the existence of EHEA in the laser cladding layer made the Cantor alloy entropy from 1.61 R to 1.77 R,greatly enhancing its thermal stability and suppressing the grave grain boundary infiltration.Joints produced via laser cladding with Nb-assisted brazing exhibited a complex microstructure(HEA/Nbss+FCC+(Co,Ni)_(2)Nb/(Zr,Nb)(Cr,Mn)_(2)+(Zr,Nb)ss/(Zr,Nb)_(2)(Cu,Ni,Co,Fe)+(Zr,Nb)(Cr,Mn)_(2)+(Zr,Nb)ss/Zr-3) and a significantly improved shear strength of 242.8 MPa at 1010℃ for 10 min,42.4%higher than that of directly brazed joints.This improvement was attributed to reduced grain boundary infiltration,alleviated residual stress due to CTE disparity,and eliminated micro-cracks in the brazing seam.This study presents an effective solution for reducing residual stresses and achieving reliable bonding between Cantor alloys and Zr-3 alloys,with potential applications in brazing CoCrFeNi-based HEA and Zr-3 due to the beneficial eutectic reaction between CoCrFeNi and Nb.
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.
基金the Xuzhou Science and Technology Bureau,No.KC23186,Jiangsu Provincial Key Laboratory of New Drug Research and Clinical Pharmacy Project(No.XZSYSKF2023013)Key Medical Disciplines of Jiangsu Province’s 14th Five-Year Plan(ZDXK202237).
文摘Background:Cisplatin(DDP)has been used in the treatment of various human cancers.However,DDP alone lacks efficacy in treating triple-negative breast cancer(TNBC),and its clinical application is often hampered by side effects.Astragalus polysaccharide(APS)is one of the active components extracted from Astragalus membranaceus and has gained attention for its various biological properties.This research is aimed to evaluate the effectiveness of a combination of APS and DDP on TNBC and explore the potential mechanisms.Methods:The efficacy and mechanisms of single or combined treatment were evaluated using Cell Counting Kit-8(CCK8)assay,Annexin V-fluorescein isothiocyanate(FITC)/propidium iodide(PI)staining,wound healing assay,trans-well invasion/migration assay,hematoxylin-eosin(HE)staining,immunohistochemical(IHC)staining,Western Blot(WB)analysis,and fluorescence-activated cell sorting(FACS).An orthotopic model of TNBC was used to assess the in vivo treatment efficacy of single or combination treatment.Results:APS significantly enhanced the anti-proliferative,anti-migratory,and anti-invasive effects of DDP on TNBC cells.The combination of APS and DDP downregulated anti-apoptotic genes(Bcl2 and Bcl-xL)while upregulating pro-apoptotic genes(Puma,Cle-Caspase3,Cle-PARP),leading to enhanced apoptosis.This combination treatment increased E-cadherin levels,decreased Vimentin,Snail,Slug,and Twist levels,and effectively suppressed epithelial-mesenchymal transition(EMT)-associated cell invasion.In the orthotopic model of TNBC,a synergistic reduction in tumor growth was observed in mice treated with APS and DDP.Additionally,the combination of APS and DDP induced the infiltration of CD8+T lymphocytes into the tumor immune microenvironment.Conclusion:The combination of APS and DDP exhibits more potent tumor inhibition and anti-tumor immunity than either agent alone,representing a novel approach to enhance therapeutic efficacy without increasing the side effects of DDP.
基金supported by grants from the Weifang Municipal Health Commission Research Programme Project(No.WFWSJK-2023-032)the Weifang Science and Technology Development Project(No.2023YX053)the Weifang Young Medical Talent Support Program Funding。
文摘Background:NDC80 is pivotal in cell division,particularly in regulating the G2/M transition and mitotic progression.Recent studies have demonstrated that NDC80 is significantly overexpressed in multiple solid tumors.Further analysis has suggested that its high expression is significantly associated with an elevated pathological grade,increased metastatic risk,and shortened overall survival in patients with cancer.However,its precise role in pan-cancer development,progression,and prognosis remains unclear.Methods:We conducted a multi-omics analysis of NDC80 using genomic,transcriptomic,and proteomic data from 33 cancer types in The Cancer Genome Atlas,Clinical Proteomic Tumor Analysis Consortium,Genotype-Tissue Expression,and Human Protein Atlas.Results:The results demonstrated frequent NDC80 mutations across multiple malignancies and significantly elevated expression in tumor tissues compared with that in their normal counterparts,correlating with worse overall and disease-free survival.Moreover,NDC80 expression was strongly associated with oncogenic pathways,key protein regulators,cellular components,myeloid-derived suppressor cell infiltration,ESTIMATE scores,and cancer-related signaling networks.Conclusions:These findings underscore the potential of NDC80 as a prognostic biomarker and therapeutic target for cancer treatment.
文摘To the Editor:Pancreatic cancer is a malignancy characterized by a poor prog-nosis,with a 5-year survival rate of<10%[1].Furthermore,only a minority of patients(<20%)qualify for curative-intent resec-tion,and even among those who undergo this procedure,the risk of recurrence within three years remains alarmingly high,reach-ing up to 70%[2].Due to the lack of specific clinical manifes-tations of pancreatic cancer,most cases have metastasized or in-vaded the major vessels around the pancreas at the time of initial diagnosis,resulting in a low surgical resection rate.Even patients who undergo surgical resection often face a poor prognosis[3].In recent years,neoadjuvant chemotherapy using agents such as gemcitabine,5-fluorouracil,albumin-bound paclitaxel,modified fluorouracil/leucovorin plus irinotecan,and oxaliplatin(mFOLFIRI-NOX),targeted therapies addressing molecular subtypes of pan-creatic cancer,and immunotherapies targeting PD-1 and PD-L1 have shown efficacy in improving the overall prognosis of patients with pancreatic cancer,although the impact remains modest[4,5].Therefore,novel therapeutic strategies and prognostic evaluation systems are urgently needed to enhance the survival of patients with pancreatic cancer.
