Helium Turbine is used in High Temperature Reactor Helium Gas Turbine (HTR-GT) system, by which the direct helium circulation between the reactor and turbine generator system will come true. Between helium turbine and...Helium Turbine is used in High Temperature Reactor Helium Gas Turbine (HTR-GT) system, by which the direct helium circulation between the reactor and turbine generator system will come true. Between helium turbine and generator, there is gearbox device which reduces the turbine rotation speed to normal speed required by the generator. Three optional gearbox schemes are discussed. The first is single reduction cylindrical gearbox, which consists of one high speed gear and one low speed gear. Its advantage is simple structure, easy to manufacture, and high reliability, while its disadvantage is large volume and misalignment of input and output axle. The second is planetary gear mechanism with static planet carrier. The third is planetary gear mechanism with static internal gear. The latter two gearbox devices have similar structure. Their advantage is small volume and high reduction gear ratio, while disadvantage are complicated structure, many gears, low reliability and low mechanical efficiency.展开更多
BACKGROUND Hepatocellular carcinoma(HCC)is the most common form of liver cancer that has limited treatment options and a poor prognosis.Transarterial chemoembolization(TACE)is the first-line treatment for intermediate...BACKGROUND Hepatocellular carcinoma(HCC)is the most common form of liver cancer that has limited treatment options and a poor prognosis.Transarterial chemoembolization(TACE)is the first-line treatment for intermediate-stage HCC but can induce tumour hypoxia,thereby promoting angiogenesis.Recent studies suggested that combining TACE with anti-angiogenic therapies and immunotherapy might im-prove efficacy.Lenvatinib,a tyrosine kinase inhibitor,has demonstrated superior outcomes compared to sorafenib,while immune checkpoint inhibitors such as sintilimab show potential when combined with TACE.However,the efficacy and safety of TACE combined with lenvatinib and sintilimab(TACE+SL)compared to TACE with lenvatinib alone(TACE+L)in patients with intermediate-ad-vanced HCC has not yet been investigated.AIM To evaluate the efficacy and safety of TACE+SL therapy in comparison to TACE+L therapy in patients with intermediate-advanced HCC.METHODS A retrospective analysis was performed on patients with intermediate-advanced HCC who received TACE plus lenvatinib with or without sintilimab between September 2019 and September 2022.Baseline characteristics were compared,and propensity score matching was applied.Overall survival(OS),progression-free survival(PFS),and objective response rate(ORR)were evaluated between the two groups,and adverse events were analyzed.RESULTS The study included 57 patients,with 30 in the TACE+SL group and 27 in the TACE+L group.The TACE+SL group demonstrated significantly improved median PFS and OS compared to the TACE+L group(PFS:14.1 months vs 9.6 months,P=0.016;OS:22.4 months vs 14.1 months,P=0.039),along with a higher ORR(70.0%vs 55.6%).After propensity score matching,30 patients were included,with the TACE+SL group again showing longer median PFS and a trend toward improved OS(PFS:14.6 months vs 9.2 months,P=0.012;OS:23.9 months vs 16.3 months,P=0.063),and a higher ORR(73.3%vs 53.3%).No severe adverse events were reported.CONCLUSION TACE+SL demonstrated superior outcomes in terms of OS and PFS,compared to TACE+L.These findings suggest that the addition of sintilimab might enhance the therapeutic response in patients with intermediate-advanced HCC.展开更多
Precise control and measurement of nanoparticles using low-power optical tweezers are pivotal for advancing single-particle analysis,nanoscale sensing,and energy transport research.In this work,we present the tipassis...Precise control and measurement of nanoparticles using low-power optical tweezers are pivotal for advancing single-particle analysis,nanoscale sensing,and energy transport research.In this work,we present the tipassisted nanoparticle capture system that simultaneously achieves localized temperature probing and nanoparticle trapping,significantly lowering the required laser power input.Unlike traditional metal-tip plasmonic techniques that predominantly rely on intense electric field gradients,our approach employs a silicon nanotip under resonant laser excitation,uniquely integrating optical forces,thermophoretic forces,and interatomic interactions for stable nanoparticle confinement.This synergistic collaboration mechanism enables approximately a 42%reduction in laser power density compared to conventional bowtie nanoaperture methods.This experimental method achieved direct and simultaneous Raman-based measurements of localized thermal dynamics,providing new insights into nanoscale thermodynamics during optical trapping.Additionally,the silicon nanotip demonstrates reduced thermal transport due to its confined nanoscale geometry,aligning closely with our theoretical predictions.Our integrated strategy of efficient nanoparticle manipulation coupled with precise thermal probing not only enhances overall energy efficiency but also broadens the scope of potential applications in cutting-edge nanoscience and nanotechnology.展开更多
Large-scale damming has emerged as a prevalent global trend,significantly impacting nutrient transport and transformation,as well as the downstream ecological environment.Nitrogen and phosphorus are fundamental elemen...Large-scale damming has emerged as a prevalent global trend,significantly impacting nutrient transport and transformation,as well as the downstream ecological environment.Nitrogen and phosphorus are fundamental elements of primary productivity in aquatic ecosystems and serve as key limiting factors in reservoir eutrophication.This review focuses on the impact of damming on the transport and transformation of nitrogen and phosphorus,regarding changes in nutrient concentrations,fluxes,and proportions.Spatial changes in nitrogen and phosphorus concentrations primarily occur at the inlet and outlet of reservoirs,while temporal changes often exhibit seasonal patterns.At a global scale,phosphorus is preferentially removed from reservoirs compared to nitrogen.The factors influencing the transport and transformation processes of nitrogen and phosphorus in reservoirs include the physicochemical properties of water bodies and human activities.Additionally,nitrogen dynamics are affected by reservoir age,storage capacity,and water storage regulation modes,whereas phosphorus dynamics are also influenced by hydrodynamic conditions.Finally,this review summarizes the impact of damming on the downstream ecological environment and outlines future research directions,providing theoretical support for the management of river–reservoir ecosystems and promoting the green and sustainable development of hydropower in the context of carbon peaking and carbon neutrality goals.展开更多
The negative ion based neutral beam injector(NNBI)with a beam energy of 400 keV is one of the subsystems at the Comprehensive Research fAcility for Fusion Technology(CRAFT)in China.The distributed capacitance of the h...The negative ion based neutral beam injector(NNBI)with a beam energy of 400 keV is one of the subsystems at the Comprehensive Research fAcility for Fusion Technology(CRAFT)in China.The distributed capacitance of the high-voltage components is an important basis for the design of surge suppression devices at CRAFT NNBI.This study conducted calculations of distributed capacitance for the key components,including the high-voltage deck,transmission line and isolation transformer in the power supply system using the finite element method.The relationship between the high-voltage deck(HVD)distributed capacitance and the distance from the wall is discussed.The differences in distributed capacitance and energy storage between noncoaxial and coaxial transmission lines are also debated.Finally,the capacitance between the primary and secondary windings of the-400 kV isolation transformer,as well as between the secondary winding and the oil tank casing,was calculated.展开更多
Background:Psychosocial functioning and quality of life(QoL)are strongly associated with outcomes in pediatric heart transplant recipients.The data in pediatric transplantation,however,is limited.This study aims to in...Background:Psychosocial functioning and quality of life(QoL)are strongly associated with outcomes in pediatric heart transplant recipients.The data in pediatric transplantation,however,is limited.This study aims to investigate the associations of perioperative anxiety and depression with postoperative complications,sociodemographic and clinical characteristics.Methods:This observational,analytical,longitudinal study included 42 pediatric participants aged 8 to 16 years old.Preoperative psychological assessments were completed by 36 children,the remaining 6 were unable to participate due to invasive ventilation,extracorporeal membrane oxygenation(ECMO),and physical debilitation.Postoperatively,all 42 subjects completed the psychosocial evaluations.Data on recipients characteristics,family characteristics and clinical parameters were collected.Anxiety and depression were assessed using the Screen for Child Anxiety Related Emotional Disorders(SCARED)and the Depression Self-Rating Scale for Children(DSRSC).The Short Form-36 Health Survey(SF-36)was applied to assess the health-related QoL.Results:Before transplantation,91.7%(33/36)of the children exhibited symptoms of anxiety,and an identical proportion(91.7%,33/36)showed signs of depression.After transplantation,the rates of anxiety and depression decreased to 35.7%(15/42)and 11.9%(5/42),respectively.Longer disease course(p=0.042),preoperative hypoalbuminemia(p=0.032),older age(p=0.024),postoperative hypertension(p=0.011),and postoperative CRRT(p=0.015)result in depression symptoms.Preoperative hypoalbuminemia(p=0.032)was also more common in the anxiety group.Additionally,children with psychosocial risks had significantly lower QoL scores in general health(p=0.008)and mental health(p=0.015).Conclusions:Perioperative anxiety and depression are highly prevalent among pediatric heart transplant recipients.Although significant improvements in psychosocial risks were observed at posttransplantation,approximately 40%children continued to experience psychosocial challenges.展开更多
In recent years,superhard coatings have emerged as a focal point in metal material research due to their innovative design strategies and exceptional mechanical properties.They are widely utilized in industries such a...In recent years,superhard coatings have emerged as a focal point in metal material research due to their innovative design strategies and exceptional mechanical properties.They are widely utilized in industries such as shielding,oil extraction,and coal mining.However,in practical applications,tools often suffer from wear,fractures,plastic deformation,and other types of failure,directly impacting machining efficiency,costs,and product quality.To mitigate these challenges,the selection of appropriate tool materials and preparation methods is critical to ensure sustained production efficiency.Therefore,it is essential to identify and develop coating materials with superior performance.Recent advancements in superhard coatings are reviewed comprehensively;preparation methods are discussed for superhard tools;diamond coatings,diamond-like carbon coatings,cubic boron nitride coatings and graphite carbon nitride coatings are examined specifically.It analyzes their microstructures,phase transformation processes,mechanical properties,and formation mechanisms,while also evaluating properties such as wear resistance,corrosion resistance,and high hardness.The applicability of existing theoretical models is verified and new frameworks for future superhard coating designs are proposed.Moreover,the current research limitations in tool coatings are identified and directions for future research and development are proposed.展开更多
The growing presence of emerging pollutants in the environment has led to a focus on developing new treatment technologies to address the limitations of traditional methods.Recent advancements in combining photocataly...The growing presence of emerging pollutants in the environment has led to a focus on developing new treatment technologies to address the limitations of traditional methods.Recent advancements in combining photocatalysis with biodegradation for pollutant treatment have garnered significant attention.This is due to the rapid and uncontrolled chemical reactions in single photocatalytic processes,which often result in the buildup of harmful by-products and over-oxidation residues.Additionally,relying solely on biodegradation is challenging for breaking down emerging pollutants that possess high concentrations and intricate structures.Therefore,the intimately coupled photocatalysis and biodegradation(ICPB)systems,along with the photocatalytic microbial fuel cells(PMFCs),as a new approach to treat pollutants.These systems combine the benefits of biodegradation and photocatalytic reactions,providing cost-effective,eco-friendly,and sustainable solutions with significant promise.In order to demonstrate the ICPB system and the PMFCs system as rational options for pollutant removal,the mechanisms of pollutant degradation by the two systems have been analyzed in depth,and recent advances in photocatalysts,biofilms,and carriers/configurations in the two systems have been summarized.Furthermore,the practical applications of the ICPB system versus the PMFCs system for pollutant removal are also summarized and highlighted.This review further points out the current limitations,such as photocatalytic materials that are still challenging in terms of commercial viability for practical applications,and looks forward to the prospects of the ICPB system versus the PMFCs system for the treatment of pollutants to promote practical applications.展开更多
Surface tension-induced shrinkage of heterogeneously bonded interfaces is a key factor in limiting the performance of nanostructures.Herein,we demonstrate a laser-induced thermo-compression bonding technology to suppr...Surface tension-induced shrinkage of heterogeneously bonded interfaces is a key factor in limiting the performance of nanostructures.Herein,we demonstrate a laser-induced thermo-compression bonding technology to suppress surface tension-induced shrinkage of Cu-Au bonded interface.A focused laser beam is used to apply localized heating and scattering force to the exposed Cu nanowire.The laser-induced scattering force and the heating can be adjusted by regulating the exposure intensity.When the ratio of scattering forces to the gravity of the exposed nanowire reaches 3.6×10^(3),the molten Cu nanowire is compressed into flattened shape rather than shrinking into nanosphere by the surface tension.As a result,the Cu-Au bonding interface is broadened fourfold by the scattering force,leading to a reduction in contact resistance of approximately 56%.This noncontact thermo-compression bonding technology provides significant possibilities for the interconnect packaging and integration of nanodevices.展开更多
Controlled by the squeezing collision between the Yangtze block and the North China block and the left movement of the Tanlu fault, the Xu-Su region developed into an arc-shaped nappe structure, and many destructive e...Controlled by the squeezing collision between the Yangtze block and the North China block and the left movement of the Tanlu fault, the Xu-Su region developed into an arc-shaped nappe structure, and many destructive earthquakes occurred in its periphery. The geological structure of this area is complex, and there is the possibility of moderate and strong earthquakes. To further explore the crust density structure and identify the main faults and deep structural features in the Xu-Su region, based on the observed seismic data and gravity/GNSS co-site observation data, combined with the EGM2008 global gravity field model, we obtained the density of three-dimensional structure using cross gradient method joint inversion. Based on this, a geological model of the Xu-Su region was established. The results show that the crustal density anomaly amplitude within 0-25 km of the Xu-Su region ranges from-280 to 490 kg/m3, showing a zonal distribution in east-west direction and a segmented north-south direction. There are several density anomalies in the shallow(0-4 km) region at Tongshan, Huaibei, Xiayi, Woyang, etc. The density anomalies are significantly correlated with the distribution of regional faults. The density structure is divided into two large regions by Subei fault, which can be further divided along the eastwest Kouziji-Nanzhao fault and Guzhen-Huaiyuan fault. The earthquakes are obviously related to the regional fault activity and the spatial distribution of abnormal bodies. The earthquake-prone areas(5-15 km) correspond to the abnormal density mutation zone, upper uplift zone, and transformation zone near Xiaoxian, Tongshan, and Xushuanglou faults. The comprehensive results show three weak seismic activity areas in the whole region, which are located near the Huaibei, Xiaoxian, and Wohe faults. The results provide theoretical support for seismic risk analysis in this area, and these three areas should be emphasized in future seismic hazard analysis.展开更多
The surface transfer doping model has been extensively adopted as a mechanism to account for the generation of hole accumulation layers below hydrogen-terminated diamond(H-diamond)surfaces.To achieve effective surface...The surface transfer doping model has been extensively adopted as a mechanism to account for the generation of hole accumulation layers below hydrogen-terminated diamond(H-diamond)surfaces.To achieve effective surface transfer doping,surface electron acceptor materials with high electron affinity(EA)are required to produce a high density of two-dimensional hole gas(2DHG)on the H-diamond subsurface.We have established ingenious theoretical models to demonstrate that even if these solid materials do not have a high EA value,they remain capable of absorbing electrons from the H-diamond surface by forming a negatively charged interface to act as a surface electron acceptor in the surface transfer doping model.Our calculations,particularly for the local density of states,provide compelling evidence that the effect of an interface with negative charges induces an upward band bending on the H-diamond side.Furthermore,the valence band maximum of the diamond atoms at the interface crosses the Fermi level,giving rise to strong surface transfer p-type doping.These results give a strong theoretical interpretation of the origin of 2DHG on H-diamond surfaces.The proposed guidelines contribute to further improvements in the performance of 2DHG H-diamond field effect transistors.展开更多
Neutral beam injection(NBI)has been proven as a reliable heating and current drive method for fusion plasma.For the high-energy NBI system(particle energy>150 ke V)of large-scale fusion devices,the negative ion sou...Neutral beam injection(NBI)has been proven as a reliable heating and current drive method for fusion plasma.For the high-energy NBI system(particle energy>150 ke V)of large-scale fusion devices,the negative ion source neutral beam injection(NNBI)system is inevitable,which can obtain an acceptable neutralization efficiency(>55%).But the NNBI system is very complex and challengeable.To explore and master the key NNBI technology for future fusion reactor in China,an NNBI test facility is under development in the framework of the Comprehensive Research Facility for Fusion Technology(CRAFT).The initial goal of CRAFT NNBI facility is to achieve a 2 MW hydrogen neutral beam at the energy of 200–400 ke V for lasting 100 s.In the first operation of the CRAFT NNBI facility,a negative ion source with dual RF drivers was developed and tested.By using the 50 keV accelerator,the long-pulse and highcurrent extractions of negative hydrogen ions have been achieved and the typical values were 55.4 keV,7.3 A(~123 A/m^(2)),105 s and 55.0 keV,14.7 A(~248 A/m^(2)),30 s,respectively.By using the 200 keV accelerator,the megawatt-class negative hydrogen beam has also been achieved(135.9 keV,8.9 A,8 s).The whole process of the gas neutralization of negative ion beam,electric removal of residual ions,and beam transport have been demonstrated experimentally.展开更多
Dear Editor, Induced pluripotent stem （iPS） cells have recently been generated by directly introducing several transcription factors into differentiated human somatic cells, and these iPS cells show great similarit...Dear Editor, Induced pluripotent stem （iPS） cells have recently been generated by directly introducing several transcription factors into differentiated human somatic cells, and these iPS cells show great similarities to embryo-derived ES cells. Moreover, patient-specific iPS cells have recently been generated, and these studies provided hopes for patients with genetic and degenerative diseases . β-thalassemia is an inherited blood disorder that is characterized by reduced synthesis of hemoglobin subunit beta （hemoglobin β-chain）. Individuals with thalassemia major （also called Cooley＇s anemia） have severe anemia and hepatosplenomegaly; without treatment, affected children have severe failure to thrive and a shortened life expectancy. Even with transfusion and chelation therapy treatments, the life span of patients with thalassemia major can only be extended for a limited time.展开更多
The surface hydrophobization and flotation of a xanthate−hydroxamate collector toward copper oxide mineral were compared with the combined collectors of xanthate and hydroxamate through water contact angle(WCA)and mic...The surface hydrophobization and flotation of a xanthate−hydroxamate collector toward copper oxide mineral were compared with the combined collectors of xanthate and hydroxamate through water contact angle(WCA)and micro-flotation experiments.The results showed that S-[(2-hydroxyamino)-2-oxoethyl]-O-octyl-dithiocarbonate ester(HAOODE)exhibited stronger hydrophobization and better flotation performance to malachite(Cu2(OH)2CO3)than octyl-hydroxamic acid(OHA)and its combination with S-allyl-O-ethyl xanthate ester(AEXE).To understand the hydrophobic intensification mechanism of HAOODE to malachite,zeta potential,atomic force microscopy(AFM)and XPS measurements were carried out.The results recommended that malachite chemisorbed HAOODE to form Cu—HAOODE complexes in which the hydroxamate—(O,O)—Cu and—O—C(—S—Cu)—S—configurations co-existed.The co-adsorption of HAOODE’s hetero-difunctional groups was more stable than the single-functionalgroup adsorption of OHA and AEXE,which produced the“loop”structure and intensified the self-assembly alignment of HAOODE on malachite surfaces.In addition,the“h”shape steric orientation of the double hydrophobic groups in HAOODE facilitated stronger hydrophobization toward malachite than the“line”or“V”hydrophobic carbon chains of OHA or AEXE.Thus,HAOODE achieved the preferable flotation recovery of malachite particles in comparison with OHA and AEXE.展开更多
Subarachnoid hemorrhage(SAH)is a dominant cause of death and disability wo rldwide.A sharp increase in intracranial pressure after SAH leads to a reduction in cerebral perfusion and insufficient blood supply for neuro...Subarachnoid hemorrhage(SAH)is a dominant cause of death and disability wo rldwide.A sharp increase in intracranial pressure after SAH leads to a reduction in cerebral perfusion and insufficient blood supply for neuro ns,which subsequently promotes a series of pathophysiological responses leading to neuronal death.Many previous experimental studies have reported that excitotoxicity,mitochondrial death pathways,the release of free radicals,protein misfolding,apoptosis,nec rosis,autophagy,and inflammation are involved solely or in combination in this disorder.Among them,irreversible neuronal apoptosis plays a key role in both short-and long-term prognoses after SAH.Neuronal apoptosis occurs through multiple pathways including extrinsic,mitochondrial,endoplasmic reticulum,p53 and oxidative stress.Meanwhile,a large number of blood contents enter the subarachnoid space after SAH,and the secondary metabolites,including oxygenated hemoglo bin and heme,further aggravate the destruction of the blood-brain barrier and vasogenic and cytotoxic brain edema,causing early brain injury and delayed cerebral ischemia,and ultimately increasing neuronal apoptosis.Even there is no clear and effective therapeutic strategy for SAH thus far,but by understanding apoptosis,we might excavate new ideas and approaches,as targeting the upstream and downstream molecules of apoptosis-related pathways shows promise in the treatment of SAH.In this review,we summarize the existing evidence on molecules and related drugs or molecules involved in the apoptotic pathway after SAH,which provides a possible target or new strategy for the treatment of SAH.展开更多
AIM:To evaluate the clinical results of angiography and embolization for massive gastrointestinal hemorrhage after abdominal surgery.METHODS:This retrospective study included 26 patients with postoperative hemorrhage ...AIM:To evaluate the clinical results of angiography and embolization for massive gastrointestinal hemorrhage after abdominal surgery.METHODS:This retrospective study included 26 patients with postoperative hemorrhage after abdominal surgery. All patients underwent emergency transarterial angiography,and 21 patients underwent emergency embolization. We retrospectively analyzed the angiographic features and the clinical outcomes of transcatheter arterial embolization.RESULTS:Angiography showed that a discrete bleeding focus was detected in 21(81%) of 26 patients.Positive angiographic findings included extravasations of contrast medium(n = 9),pseudoaneurysms(n =9),and fusiform aneurysms(n = 3). Transarterial embolization was technically successful in 21(95%) of 22patients. Clinical success was achieved in 18(82%) of 22 patients. No postembolization complications were observed. Three patients died of rebleeding.CONCLUSION:The positive rate of angiographic findings in 26 patients with postoperative gastrointestinal hemorrhage was 81%. Transcatheter arterial embolization seems to be an effective and safe method in the management of postoperative gastrointestinal hemorrhage.展开更多
Intervertebral disc(IVD) degeneration(IVDD) is the main cause of low back pain with major social and economic burdens;however, its underlying molecular mechanisms remain poorly defined. Here we show that the focal adh...Intervertebral disc(IVD) degeneration(IVDD) is the main cause of low back pain with major social and economic burdens;however, its underlying molecular mechanisms remain poorly defined. Here we show that the focal adhesion protein Kindlin-2 is highly expressed in the nucleus pulposus(NP), but not in the anulus fibrosus and the cartilaginous endplates, in the IVD tissues. Expression of Kindlin-2 is drastically decreased in NP cells in aged mice and severe IVDD patients. Inducible deletion of Kindlin-2 in NP cells in adult mice causes spontaneous and striking IVDD-like phenotypes in lumbar IVDs and largely accelerates progression of coccygeal IVDD in the presence of abnormal mechanical stress. Kindlin-2 loss activates Nlrp3 inflammasome and stimulates expression of IL-1β in NP cells, which in turn downregulates Kindlin-2. This vicious cycle promotes extracellular matrix(ECM) catabolism and NP cell apoptosis. Furthermore, abnormal mechanical stress reduces expression of Kindlin-2, which exacerbates Nlrp3 inflammasome activation, cell apoptosis, and ECM catabolism in NP cells caused by Kindlin-2 deficiency. In vivo blocking Nlrp3 inflammasome activation prevents IVDD progression induced by Kindlin-2 loss and abnormal mechanical stress. Of translational significance, adeno-associated virus-mediated overexpression of Kindlin-2 inhibits ECM catabolism and cell apoptosis in primary human NP cells in vitro and alleviates coccygeal IVDD progression caused by mechanical stress in rat. Collectively, we establish critical roles of Kindlin-2 in inhibiting Nlrp3 inflammasome activation and maintaining integrity of the IVD homeostasis and define a novel target for the prevention and treatment of IVDD.展开更多
In order to figure out the oxidation behavior of steels during heating,five micro-alloyed steels were subjected to continuous and isothermal oxidation using the thermo gravimetric analyzer and the Gleeble-3500thermo-m...In order to figure out the oxidation behavior of steels during heating,five micro-alloyed steels were subjected to continuous and isothermal oxidation using the thermo gravimetric analyzer and the Gleeble-3500thermo-mechanical simulator.The microstructure of oxide scales,especially the thickness fractions of Fe2O3,Fe3O4 and FeO layers,was analyzed using the scanning electron microscope（SEM）,electron probe microanalyzer（EPMA）and electron backscattered diffraction（EBSD）techniques.The micro-alloyed steels containing alloying elements（Si,Cr,Ni and Cu）show a higher oxidation resistance compared with the low carbon steel.It is found that alloying elements accumulated at scale/substrate interface during high temperature oxidation.Alloying elements function in two ways in the oxidation of steels：one is enhancing the scale/substrate interface and consequently suppressing the blister of scales;and the other is impeding the outward diffusion of iron cations from substrate to scales,resulting in the decrease of oxidation rate.As the diffusion of iron cations is impeded,the thickness fractions of Fe2O3 and Fe3O4of micro-alloyed steels are more than those of low carbon steels.展开更多
文摘Helium Turbine is used in High Temperature Reactor Helium Gas Turbine (HTR-GT) system, by which the direct helium circulation between the reactor and turbine generator system will come true. Between helium turbine and generator, there is gearbox device which reduces the turbine rotation speed to normal speed required by the generator. Three optional gearbox schemes are discussed. The first is single reduction cylindrical gearbox, which consists of one high speed gear and one low speed gear. Its advantage is simple structure, easy to manufacture, and high reliability, while its disadvantage is large volume and misalignment of input and output axle. The second is planetary gear mechanism with static planet carrier. The third is planetary gear mechanism with static internal gear. The latter two gearbox devices have similar structure. Their advantage is small volume and high reduction gear ratio, while disadvantage are complicated structure, many gears, low reliability and low mechanical efficiency.
文摘BACKGROUND Hepatocellular carcinoma(HCC)is the most common form of liver cancer that has limited treatment options and a poor prognosis.Transarterial chemoembolization(TACE)is the first-line treatment for intermediate-stage HCC but can induce tumour hypoxia,thereby promoting angiogenesis.Recent studies suggested that combining TACE with anti-angiogenic therapies and immunotherapy might im-prove efficacy.Lenvatinib,a tyrosine kinase inhibitor,has demonstrated superior outcomes compared to sorafenib,while immune checkpoint inhibitors such as sintilimab show potential when combined with TACE.However,the efficacy and safety of TACE combined with lenvatinib and sintilimab(TACE+SL)compared to TACE with lenvatinib alone(TACE+L)in patients with intermediate-ad-vanced HCC has not yet been investigated.AIM To evaluate the efficacy and safety of TACE+SL therapy in comparison to TACE+L therapy in patients with intermediate-advanced HCC.METHODS A retrospective analysis was performed on patients with intermediate-advanced HCC who received TACE plus lenvatinib with or without sintilimab between September 2019 and September 2022.Baseline characteristics were compared,and propensity score matching was applied.Overall survival(OS),progression-free survival(PFS),and objective response rate(ORR)were evaluated between the two groups,and adverse events were analyzed.RESULTS The study included 57 patients,with 30 in the TACE+SL group and 27 in the TACE+L group.The TACE+SL group demonstrated significantly improved median PFS and OS compared to the TACE+L group(PFS:14.1 months vs 9.6 months,P=0.016;OS:22.4 months vs 14.1 months,P=0.039),along with a higher ORR(70.0%vs 55.6%).After propensity score matching,30 patients were included,with the TACE+SL group again showing longer median PFS and a trend toward improved OS(PFS:14.6 months vs 9.2 months,P=0.012;OS:23.9 months vs 16.3 months,P=0.063),and a higher ORR(73.3%vs 53.3%).No severe adverse events were reported.CONCLUSION TACE+SL demonstrated superior outcomes in terms of OS and PFS,compared to TACE+L.These findings suggest that the addition of sintilimab might enhance the therapeutic response in patients with intermediate-advanced HCC.
基金supported by the National Natural Science Foundation of China(Grant No.52206107)the National Key R&D Program of China(Grant No.2023YFE0120200)。
文摘Precise control and measurement of nanoparticles using low-power optical tweezers are pivotal for advancing single-particle analysis,nanoscale sensing,and energy transport research.In this work,we present the tipassisted nanoparticle capture system that simultaneously achieves localized temperature probing and nanoparticle trapping,significantly lowering the required laser power input.Unlike traditional metal-tip plasmonic techniques that predominantly rely on intense electric field gradients,our approach employs a silicon nanotip under resonant laser excitation,uniquely integrating optical forces,thermophoretic forces,and interatomic interactions for stable nanoparticle confinement.This synergistic collaboration mechanism enables approximately a 42%reduction in laser power density compared to conventional bowtie nanoaperture methods.This experimental method achieved direct and simultaneous Raman-based measurements of localized thermal dynamics,providing new insights into nanoscale thermodynamics during optical trapping.Additionally,the silicon nanotip demonstrates reduced thermal transport due to its confined nanoscale geometry,aligning closely with our theoretical predictions.Our integrated strategy of efficient nanoparticle manipulation coupled with precise thermal probing not only enhances overall energy efficiency but also broadens the scope of potential applications in cutting-edge nanoscience and nanotechnology.
基金supported by the General Project of the National Natural Science Foundation of China(Grant No.42377054)the National Natural Science Fund for Young Scholars(Grant No.42007149)the Key Project of the Major Research Plan of the National Natural Science Foundation of China(Grant No.92047201).
文摘Large-scale damming has emerged as a prevalent global trend,significantly impacting nutrient transport and transformation,as well as the downstream ecological environment.Nitrogen and phosphorus are fundamental elements of primary productivity in aquatic ecosystems and serve as key limiting factors in reservoir eutrophication.This review focuses on the impact of damming on the transport and transformation of nitrogen and phosphorus,regarding changes in nutrient concentrations,fluxes,and proportions.Spatial changes in nitrogen and phosphorus concentrations primarily occur at the inlet and outlet of reservoirs,while temporal changes often exhibit seasonal patterns.At a global scale,phosphorus is preferentially removed from reservoirs compared to nitrogen.The factors influencing the transport and transformation processes of nitrogen and phosphorus in reservoirs include the physicochemical properties of water bodies and human activities.Additionally,nitrogen dynamics are affected by reservoir age,storage capacity,and water storage regulation modes,whereas phosphorus dynamics are also influenced by hydrodynamic conditions.Finally,this review summarizes the impact of damming on the downstream ecological environment and outlines future research directions,providing theoretical support for the management of river–reservoir ecosystems and promoting the green and sustainable development of hydropower in the context of carbon peaking and carbon neutrality goals.
基金supported by the Comprehensive Research Facility for Fusion Technology Program of China(No.2018000052-73-01-001228)National Natural Science Foundation of China(No.11975263)Postgraduate Research and Practice Innovation Program of NUAA(No.xcxjh20231501)。
文摘The negative ion based neutral beam injector(NNBI)with a beam energy of 400 keV is one of the subsystems at the Comprehensive Research fAcility for Fusion Technology(CRAFT)in China.The distributed capacitance of the high-voltage components is an important basis for the design of surge suppression devices at CRAFT NNBI.This study conducted calculations of distributed capacitance for the key components,including the high-voltage deck,transmission line and isolation transformer in the power supply system using the finite element method.The relationship between the high-voltage deck(HVD)distributed capacitance and the distance from the wall is discussed.The differences in distributed capacitance and energy storage between noncoaxial and coaxial transmission lines are also debated.Finally,the capacitance between the primary and secondary windings of the-400 kV isolation transformer,as well as between the secondary winding and the oil tank casing,was calculated.
文摘Background:Psychosocial functioning and quality of life(QoL)are strongly associated with outcomes in pediatric heart transplant recipients.The data in pediatric transplantation,however,is limited.This study aims to investigate the associations of perioperative anxiety and depression with postoperative complications,sociodemographic and clinical characteristics.Methods:This observational,analytical,longitudinal study included 42 pediatric participants aged 8 to 16 years old.Preoperative psychological assessments were completed by 36 children,the remaining 6 were unable to participate due to invasive ventilation,extracorporeal membrane oxygenation(ECMO),and physical debilitation.Postoperatively,all 42 subjects completed the psychosocial evaluations.Data on recipients characteristics,family characteristics and clinical parameters were collected.Anxiety and depression were assessed using the Screen for Child Anxiety Related Emotional Disorders(SCARED)and the Depression Self-Rating Scale for Children(DSRSC).The Short Form-36 Health Survey(SF-36)was applied to assess the health-related QoL.Results:Before transplantation,91.7%(33/36)of the children exhibited symptoms of anxiety,and an identical proportion(91.7%,33/36)showed signs of depression.After transplantation,the rates of anxiety and depression decreased to 35.7%(15/42)and 11.9%(5/42),respectively.Longer disease course(p=0.042),preoperative hypoalbuminemia(p=0.032),older age(p=0.024),postoperative hypertension(p=0.011),and postoperative CRRT(p=0.015)result in depression symptoms.Preoperative hypoalbuminemia(p=0.032)was also more common in the anxiety group.Additionally,children with psychosocial risks had significantly lower QoL scores in general health(p=0.008)and mental health(p=0.015).Conclusions:Perioperative anxiety and depression are highly prevalent among pediatric heart transplant recipients.Although significant improvements in psychosocial risks were observed at posttransplantation,approximately 40%children continued to experience psychosocial challenges.
基金financially supported by the National Natural Science Foundation of China(No.52475347)the National Program of Foreign Experts of China(No.G2023026003L)+3 种基金the High-end Foreign Experts Introduction Project of Henan Province,China(No.HNGD2025026)Project supported by the Program for the Top Young Talents of Henan Province,China,Project(No.242102521057)sponsored by the International Science and Technology Cooperation Project of Henan Province,China,and projects supported by China Postdoctoral Foundation(No.2023M740475)Henan Provincial Science and Technology R&D Joint Fund(Industry)(No.225101610002).
文摘In recent years,superhard coatings have emerged as a focal point in metal material research due to their innovative design strategies and exceptional mechanical properties.They are widely utilized in industries such as shielding,oil extraction,and coal mining.However,in practical applications,tools often suffer from wear,fractures,plastic deformation,and other types of failure,directly impacting machining efficiency,costs,and product quality.To mitigate these challenges,the selection of appropriate tool materials and preparation methods is critical to ensure sustained production efficiency.Therefore,it is essential to identify and develop coating materials with superior performance.Recent advancements in superhard coatings are reviewed comprehensively;preparation methods are discussed for superhard tools;diamond coatings,diamond-like carbon coatings,cubic boron nitride coatings and graphite carbon nitride coatings are examined specifically.It analyzes their microstructures,phase transformation processes,mechanical properties,and formation mechanisms,while also evaluating properties such as wear resistance,corrosion resistance,and high hardness.The applicability of existing theoretical models is verified and new frameworks for future superhard coating designs are proposed.Moreover,the current research limitations in tool coatings are identified and directions for future research and development are proposed.
文摘The growing presence of emerging pollutants in the environment has led to a focus on developing new treatment technologies to address the limitations of traditional methods.Recent advancements in combining photocatalysis with biodegradation for pollutant treatment have garnered significant attention.This is due to the rapid and uncontrolled chemical reactions in single photocatalytic processes,which often result in the buildup of harmful by-products and over-oxidation residues.Additionally,relying solely on biodegradation is challenging for breaking down emerging pollutants that possess high concentrations and intricate structures.Therefore,the intimately coupled photocatalysis and biodegradation(ICPB)systems,along with the photocatalytic microbial fuel cells(PMFCs),as a new approach to treat pollutants.These systems combine the benefits of biodegradation and photocatalytic reactions,providing cost-effective,eco-friendly,and sustainable solutions with significant promise.In order to demonstrate the ICPB system and the PMFCs system as rational options for pollutant removal,the mechanisms of pollutant degradation by the two systems have been analyzed in depth,and recent advances in photocatalysts,biofilms,and carriers/configurations in the two systems have been summarized.Furthermore,the practical applications of the ICPB system versus the PMFCs system for pollutant removal are also summarized and highlighted.This review further points out the current limitations,such as photocatalytic materials that are still challenging in terms of commercial viability for practical applications,and looks forward to the prospects of the ICPB system versus the PMFCs system for the treatment of pollutants to promote practical applications.
基金supported by the National Natural Science Foundation of China(Nos.52305612 and U20A6004)Open Fund of Hubei Key Laboratory of Electronic Manufacturing and Packaging Integration(Wuhan University)(NO.EMPI2023015).
文摘Surface tension-induced shrinkage of heterogeneously bonded interfaces is a key factor in limiting the performance of nanostructures.Herein,we demonstrate a laser-induced thermo-compression bonding technology to suppress surface tension-induced shrinkage of Cu-Au bonded interface.A focused laser beam is used to apply localized heating and scattering force to the exposed Cu nanowire.The laser-induced scattering force and the heating can be adjusted by regulating the exposure intensity.When the ratio of scattering forces to the gravity of the exposed nanowire reaches 3.6×10^(3),the molten Cu nanowire is compressed into flattened shape rather than shrinking into nanosphere by the surface tension.As a result,the Cu-Au bonding interface is broadened fourfold by the scattering force,leading to a reduction in contact resistance of approximately 56%.This noncontact thermo-compression bonding technology provides significant possibilities for the interconnect packaging and integration of nanodevices.
基金funded by the National Natural Science Foundation of China(No.42174104,No.42204089)the Hubei Provincial Natural Science Foundation of China(2022CFB350)+1 种基金the Basic Research Fund of Institute of Seismology,China Earthquake Administration(IS202326341)Open Fund ofWuhan,Gravitation and Solid Earth Tides,National Observation and Research Station(WHYWZ202108,WHYWZ202301)。
文摘Controlled by the squeezing collision between the Yangtze block and the North China block and the left movement of the Tanlu fault, the Xu-Su region developed into an arc-shaped nappe structure, and many destructive earthquakes occurred in its periphery. The geological structure of this area is complex, and there is the possibility of moderate and strong earthquakes. To further explore the crust density structure and identify the main faults and deep structural features in the Xu-Su region, based on the observed seismic data and gravity/GNSS co-site observation data, combined with the EGM2008 global gravity field model, we obtained the density of three-dimensional structure using cross gradient method joint inversion. Based on this, a geological model of the Xu-Su region was established. The results show that the crustal density anomaly amplitude within 0-25 km of the Xu-Su region ranges from-280 to 490 kg/m3, showing a zonal distribution in east-west direction and a segmented north-south direction. There are several density anomalies in the shallow(0-4 km) region at Tongshan, Huaibei, Xiayi, Woyang, etc. The density anomalies are significantly correlated with the distribution of regional faults. The density structure is divided into two large regions by Subei fault, which can be further divided along the eastwest Kouziji-Nanzhao fault and Guzhen-Huaiyuan fault. The earthquakes are obviously related to the regional fault activity and the spatial distribution of abnormal bodies. The earthquake-prone areas(5-15 km) correspond to the abnormal density mutation zone, upper uplift zone, and transformation zone near Xiaoxian, Tongshan, and Xushuanglou faults. The comprehensive results show three weak seismic activity areas in the whole region, which are located near the Huaibei, Xiaoxian, and Wohe faults. The results provide theoretical support for seismic risk analysis in this area, and these three areas should be emphasized in future seismic hazard analysis.
基金supported by the National Nat-ural Science Foundation of China(Nos.62174122,U2241244,and 52302046)Major Program(JD)of Hubei Province(No.2023BAA008)+2 种基金the Fundamental Research Funds for the Central Universities(Nos.2042023kf0116 and 2042023kf1041)the Guangdong Basic and Applied Basic Research Foundation(Nos.2024A1515011764 and 2024A1515010383)the Open Fund of Hubei Key Laboratory of Electronic Manufacturing and Packaging Integration(Wuhan University)(No.EMPI2023016).
文摘The surface transfer doping model has been extensively adopted as a mechanism to account for the generation of hole accumulation layers below hydrogen-terminated diamond(H-diamond)surfaces.To achieve effective surface transfer doping,surface electron acceptor materials with high electron affinity(EA)are required to produce a high density of two-dimensional hole gas(2DHG)on the H-diamond subsurface.We have established ingenious theoretical models to demonstrate that even if these solid materials do not have a high EA value,they remain capable of absorbing electrons from the H-diamond surface by forming a negatively charged interface to act as a surface electron acceptor in the surface transfer doping model.Our calculations,particularly for the local density of states,provide compelling evidence that the effect of an interface with negative charges induces an upward band bending on the H-diamond side.Furthermore,the valence band maximum of the diamond atoms at the interface crosses the Fermi level,giving rise to strong surface transfer p-type doping.These results give a strong theoretical interpretation of the origin of 2DHG on H-diamond surfaces.The proposed guidelines contribute to further improvements in the performance of 2DHG H-diamond field effect transistors.
基金supported by the Comprehensive Research Facility for Fusion Technology Program of China(No.2018-000052-73-01-001228)。
文摘Neutral beam injection(NBI)has been proven as a reliable heating and current drive method for fusion plasma.For the high-energy NBI system(particle energy>150 ke V)of large-scale fusion devices,the negative ion source neutral beam injection(NNBI)system is inevitable,which can obtain an acceptable neutralization efficiency(>55%).But the NNBI system is very complex and challengeable.To explore and master the key NNBI technology for future fusion reactor in China,an NNBI test facility is under development in the framework of the Comprehensive Research Facility for Fusion Technology(CRAFT).The initial goal of CRAFT NNBI facility is to achieve a 2 MW hydrogen neutral beam at the energy of 200–400 ke V for lasting 100 s.In the first operation of the CRAFT NNBI facility,a negative ion source with dual RF drivers was developed and tested.By using the 50 keV accelerator,the long-pulse and highcurrent extractions of negative hydrogen ions have been achieved and the typical values were 55.4 keV,7.3 A(~123 A/m^(2)),105 s and 55.0 keV,14.7 A(~248 A/m^(2)),30 s,respectively.By using the 200 keV accelerator,the megawatt-class negative hydrogen beam has also been achieved(135.9 keV,8.9 A,8 s).The whole process of the gas neutralization of negative ion beam,electric removal of residual ions,and beam transport have been demonstrated experimentally.
文摘Dear Editor, Induced pluripotent stem （iPS） cells have recently been generated by directly introducing several transcription factors into differentiated human somatic cells, and these iPS cells show great similarities to embryo-derived ES cells. Moreover, patient-specific iPS cells have recently been generated, and these studies provided hopes for patients with genetic and degenerative diseases . β-thalassemia is an inherited blood disorder that is characterized by reduced synthesis of hemoglobin subunit beta （hemoglobin β-chain）. Individuals with thalassemia major （also called Cooley＇s anemia） have severe anemia and hepatosplenomegaly; without treatment, affected children have severe failure to thrive and a shortened life expectancy. Even with transfusion and chelation therapy treatments, the life span of patients with thalassemia major can only be extended for a limited time.
基金Project(51474253)supported by the National Natural Science Foundation of China。
文摘The surface hydrophobization and flotation of a xanthate−hydroxamate collector toward copper oxide mineral were compared with the combined collectors of xanthate and hydroxamate through water contact angle(WCA)and micro-flotation experiments.The results showed that S-[(2-hydroxyamino)-2-oxoethyl]-O-octyl-dithiocarbonate ester(HAOODE)exhibited stronger hydrophobization and better flotation performance to malachite(Cu2(OH)2CO3)than octyl-hydroxamic acid(OHA)and its combination with S-allyl-O-ethyl xanthate ester(AEXE).To understand the hydrophobic intensification mechanism of HAOODE to malachite,zeta potential,atomic force microscopy(AFM)and XPS measurements were carried out.The results recommended that malachite chemisorbed HAOODE to form Cu—HAOODE complexes in which the hydroxamate—(O,O)—Cu and—O—C(—S—Cu)—S—configurations co-existed.The co-adsorption of HAOODE’s hetero-difunctional groups was more stable than the single-functionalgroup adsorption of OHA and AEXE,which produced the“loop”structure and intensified the self-assembly alignment of HAOODE on malachite surfaces.In addition,the“h”shape steric orientation of the double hydrophobic groups in HAOODE facilitated stronger hydrophobization toward malachite than the“line”or“V”hydrophobic carbon chains of OHA or AEXE.Thus,HAOODE achieved the preferable flotation recovery of malachite particles in comparison with OHA and AEXE.
基金supported by the National Natural Science Foundation of China,Nos.81971870,82172173(both to MCL)。
文摘Subarachnoid hemorrhage(SAH)is a dominant cause of death and disability wo rldwide.A sharp increase in intracranial pressure after SAH leads to a reduction in cerebral perfusion and insufficient blood supply for neuro ns,which subsequently promotes a series of pathophysiological responses leading to neuronal death.Many previous experimental studies have reported that excitotoxicity,mitochondrial death pathways,the release of free radicals,protein misfolding,apoptosis,nec rosis,autophagy,and inflammation are involved solely or in combination in this disorder.Among them,irreversible neuronal apoptosis plays a key role in both short-and long-term prognoses after SAH.Neuronal apoptosis occurs through multiple pathways including extrinsic,mitochondrial,endoplasmic reticulum,p53 and oxidative stress.Meanwhile,a large number of blood contents enter the subarachnoid space after SAH,and the secondary metabolites,including oxygenated hemoglo bin and heme,further aggravate the destruction of the blood-brain barrier and vasogenic and cytotoxic brain edema,causing early brain injury and delayed cerebral ischemia,and ultimately increasing neuronal apoptosis.Even there is no clear and effective therapeutic strategy for SAH thus far,but by understanding apoptosis,we might excavate new ideas and approaches,as targeting the upstream and downstream molecules of apoptosis-related pathways shows promise in the treatment of SAH.In this review,we summarize the existing evidence on molecules and related drugs or molecules involved in the apoptotic pathway after SAH,which provides a possible target or new strategy for the treatment of SAH.
文摘AIM:To evaluate the clinical results of angiography and embolization for massive gastrointestinal hemorrhage after abdominal surgery.METHODS:This retrospective study included 26 patients with postoperative hemorrhage after abdominal surgery. All patients underwent emergency transarterial angiography,and 21 patients underwent emergency embolization. We retrospectively analyzed the angiographic features and the clinical outcomes of transcatheter arterial embolization.RESULTS:Angiography showed that a discrete bleeding focus was detected in 21(81%) of 26 patients.Positive angiographic findings included extravasations of contrast medium(n = 9),pseudoaneurysms(n =9),and fusiform aneurysms(n = 3). Transarterial embolization was technically successful in 21(95%) of 22patients. Clinical success was achieved in 18(82%) of 22 patients. No postembolization complications were observed. Three patients died of rebleeding.CONCLUSION:The positive rate of angiographic findings in 26 patients with postoperative gastrointestinal hemorrhage was 81%. Transcatheter arterial embolization seems to be an effective and safe method in the management of postoperative gastrointestinal hemorrhage.
基金partially supported by the National Key Research and Development Program of China Grants (2019YFA0906004)the National Natural Science Foundation of China Grants (81870532, 81630066, 82022047, 81991513)the Guangdong Provincial Science and Technology Innovation Council Grant (2017B030301018)
文摘Intervertebral disc(IVD) degeneration(IVDD) is the main cause of low back pain with major social and economic burdens;however, its underlying molecular mechanisms remain poorly defined. Here we show that the focal adhesion protein Kindlin-2 is highly expressed in the nucleus pulposus(NP), but not in the anulus fibrosus and the cartilaginous endplates, in the IVD tissues. Expression of Kindlin-2 is drastically decreased in NP cells in aged mice and severe IVDD patients. Inducible deletion of Kindlin-2 in NP cells in adult mice causes spontaneous and striking IVDD-like phenotypes in lumbar IVDs and largely accelerates progression of coccygeal IVDD in the presence of abnormal mechanical stress. Kindlin-2 loss activates Nlrp3 inflammasome and stimulates expression of IL-1β in NP cells, which in turn downregulates Kindlin-2. This vicious cycle promotes extracellular matrix(ECM) catabolism and NP cell apoptosis. Furthermore, abnormal mechanical stress reduces expression of Kindlin-2, which exacerbates Nlrp3 inflammasome activation, cell apoptosis, and ECM catabolism in NP cells caused by Kindlin-2 deficiency. In vivo blocking Nlrp3 inflammasome activation prevents IVDD progression induced by Kindlin-2 loss and abnormal mechanical stress. Of translational significance, adeno-associated virus-mediated overexpression of Kindlin-2 inhibits ECM catabolism and cell apoptosis in primary human NP cells in vitro and alleviates coccygeal IVDD progression caused by mechanical stress in rat. Collectively, we establish critical roles of Kindlin-2 in inhibiting Nlrp3 inflammasome activation and maintaining integrity of the IVD homeostasis and define a novel target for the prevention and treatment of IVDD.
基金Item Sponsored by National High-tech Research and Development Program(863Program)of China(2012AA03A508)National Natural Science Foundation of China(51474031)
文摘In order to figure out the oxidation behavior of steels during heating,five micro-alloyed steels were subjected to continuous and isothermal oxidation using the thermo gravimetric analyzer and the Gleeble-3500thermo-mechanical simulator.The microstructure of oxide scales,especially the thickness fractions of Fe2O3,Fe3O4 and FeO layers,was analyzed using the scanning electron microscope（SEM）,electron probe microanalyzer（EPMA）and electron backscattered diffraction（EBSD）techniques.The micro-alloyed steels containing alloying elements（Si,Cr,Ni and Cu）show a higher oxidation resistance compared with the low carbon steel.It is found that alloying elements accumulated at scale/substrate interface during high temperature oxidation.Alloying elements function in two ways in the oxidation of steels：one is enhancing the scale/substrate interface and consequently suppressing the blister of scales;and the other is impeding the outward diffusion of iron cations from substrate to scales,resulting in the decrease of oxidation rate.As the diffusion of iron cations is impeded,the thickness fractions of Fe2O3 and Fe3O4of micro-alloyed steels are more than those of low carbon steels.
