Ductile iron bars(DIBs) with a diameter of 145 mm, used for plunger pump production, were made by the horizontal continuous casting(HCC). The microstructure of the samples cut at three locations with different distanc...Ductile iron bars(DIBs) with a diameter of 145 mm, used for plunger pump production, were made by the horizontal continuous casting(HCC). The microstructure of the samples cut at three locations with different distances away from the surface(~20 mm from the surface, half of the radius and the center of the HCCDIBs)were investigated. The mechanical properties were measured by tensile and torsion tests. Results show that after the spheroidization of graphite, the iron matrix incorporates the nodules of Format I, Size 8 close to the surface, Format I, Size 7 at the half of the radius from the surface, and Format II, Size 6 in the centre of the bar,according to the ASTM A247 standard. The content of pearlite in the matrix changes from 55%(~20 mm from the surface) to 70%(half of the radius) and 80%(the center of the HCCDIBs). The strengths in tension are 552, 607 and 486 MPa with the elongations of 12.5%, 10.5% and 5.8% in samples cut at these three locations from the surface to the centre, respectively. The strength in torsion is equal to 558, 551 and 471 MPa at corresponding torsion angles of 418°, 384° and 144° respectively to the same distance from the bar surface. Fracture in tension is manifested via crack propagation through the interface between graphite nodules and matrix(Mode I), while in torsion the fracture is caused by the shear of graphite nodules(Mode II). It is shown that the transition between two fracture modes is also dependent on the size of graphite nodule. Typically, fracture Mode I was observed for nodules of smaller diameter(less than 22.7 μm) and fracture Mode II was seen for nodules of greater diameter(more than 24.8 μm).展开更多
The solidification process of a horizontally continuously cast gray iron bar of 4.6cm in diame- ter was modelled.The function describing the distribution of heat flux at the internal surface of graphite sleeve,which w...The solidification process of a horizontally continuously cast gray iron bar of 4.6cm in diame- ter was modelled.The function describing the distribution of heat flux at the internal surface of graphite sleeve,which was equal to that on the surface of the iron bar,was inversely derived using numerical calculation from the temperature distribution in the sleeve measured in real production.By using the distribution of heat flux as a boundary condition on the surface of the iron bar,the numerical simulation on solidification of the iron bar taking longitudinal heat conduction into account was made.The profile of solidification front obtained from the numer- ical simulation was approximately coincident with that in real production.In addition,the quantitative relationships of the thickness of solidified shell at the exit of the mold to the main technological parameters,including the temperature of liquid iron at the entrance of the mold, the moving speed of the bar and the intensity of water cooling,were obtained from the numeri- cal simulation.展开更多
Controlling the adhesion of potentially corrosive substances from flue gas on grate bar is crucial for extending the operational lifespan of the equipment.The adhesive behaviour and mechanism of ultrafine particulate ...Controlling the adhesion of potentially corrosive substances from flue gas on grate bar is crucial for extending the operational lifespan of the equipment.The adhesive behaviour and mechanism of ultrafine particulate matters(UPM)throughout the sintering process were elucidated,and measures to control adhesion on grate bars were developed.Research findings indicated that a small quantity of UPM were found on grate bar during the initial sintering stages(ignition stage and middle stageⅠandⅡ).The main compositions of UPM were FexOy-rich,CaO-rich,and aluminium silicate-rich particles.In contrast,corrosive substances like alkali metal compounds were almost absent.These UPM adhered onto grate bar primarily through inertial impaction.When moving to the final sintering stages(middle stageⅢand temperature rising stage),many UPM rich in corrosive substances like NaCl and KCl adhered to the grate bar.These UPM adhered to grate bar through thermal diffusion and vortex deposition.Solid waste water washing technology can greatly decrease the quantity of UPM(rich in NaCl and KCl)on the grate bar due to vortex deposition and thermal diffusion,and it represents a potentially promising way to control adhesion and corrosion on grate bars.展开更多
Iron deficiency anemia affects approximately 1.62 billion people worldwide,yet traditional iron supplements present bioavailability limitations and gastrointestinal side effects.This randomized,double-blind clinical t...Iron deficiency anemia affects approximately 1.62 billion people worldwide,yet traditional iron supplements present bioavailability limitations and gastrointestinal side effects.This randomized,double-blind clinical trial investigated a novel Auricularia auricula polysaccharide-iron complex(AAPIC)compared with heme iron and ferrous glycinate in 180 iron-deficient adults receiving 30 mg elemental iron daily for 12 weeks.AAPIC achieved comparable hemoglobin improvements(from 98.3±8.7 to 126.5±9.2 g/L)to heme iron(from 97.8±9.1 to 128.3±8.6 g/L)and was significantly superior to ferrous glycinate(from 98.6±8.9 to 119.7±10.3 g/L;p<0.001).Iron absorption efficiency showed AAPIC at 23.7±4.2%,heme iron at 25.1±3.8%,and ferrous glycinate at 18.4±5.1%.Toxicological assessments revealed no hepatotoxicity,nephrotoxicity,or mutagenicity.Gastrointestinal adverse events occurred in 8.3%of AAPIC recipients versus 15.0%with ferrous glycinate and 10.0%with heme iron.The polysaccharide component facilitates iron transport through enhanced intestinal uptake mechanisms.AAPIC represents a promising,well-tolerated alternative with clinical efficacy comparable to established iron formulations.展开更多
Neurodegenerative diseases are prevalent conditions that greatly impact human health.These diseases are primarily characterized by the progressive loss and eventual death of neuronal function,although the precise mech...Neurodegenerative diseases are prevalent conditions that greatly impact human health.These diseases are primarily characterized by the progressive loss and eventual death of neuronal function,although the precise mechanisms underlying these processes remain incompletely understood.Iron is an essential trace element in the human body,playing a crucial role in various biological processes.The maintenance of iron homeostasis relies on the body's intricate and nuanced regulatory mechanisms.In recent years,considerable attention has been directed toward the relationship between dysregulated iron homeostasis and neurodegenerative diseases.The regulation of iron homeostasis within cells is crucial for maintaining proper nervous system function.Research has already revealed that disruptions in iron homeostasis may lead to ferroptosis and oxidative stress,which,in turn,can impact neuronal health and contribute to the development of neurodegenerative diseases.This article primarily explores the intimate relationship between iron homeostasis and neurodegenerative diseases,aiming to provide novel insights and strategies for treating these debilitating conditions.展开更多
Centrifugal casting of ductile iron pipe is a high-temperature,semi-continuous production process.However,conducting laboratory research on the solidification process of centrifugal casting of ductile iron pipe presen...Centrifugal casting of ductile iron pipe is a high-temperature,semi-continuous production process.However,conducting laboratory research on the solidification process of centrifugal casting of ductile iron pipe presents significant challenges.In this study,a novel research method was introduced for investigating the solidification process of ductile iron pipe,namely thermal simulation of ductile iron pipe.Comparative research was conducted on the microstructure and properties of the thermal simulation sample and the ductile iron pipe.The findings indicate that the thermal simulation sample and ductile iron pipe exhibit good heat transfer similarity and microstructure similarity.The difference of cooling rate between thermal simulation sample and ductile pipe is less than 0.24℃·s^(-1),and the difference of microstructure content of free cementite,ferrite,and pearlite is less than 5%.The tensile strength of annealed ductile iron pipe is 466 MPa,with an elongation of 16.1%and a Brinell hardness of 156.5 HBW.In comparison,the tensile strength of annealed thermal simulation sample is 482.0 MPa,with an elongation of 15.5%and a Brinell hardness of 159.0 HBW.These results suggest that the thermal simulation experimental research method is both scientific and feasible,offering an objective,reliable,and cost-effective approach to laboratory research on ductile iron pipe.展开更多
With the industrialization of agriculture and the advancement of medical care,human life expectancy has increased considerably and continues to rise steadily.This results in novel and unprecedented challenges,namely o...With the industrialization of agriculture and the advancement of medical care,human life expectancy has increased considerably and continues to rise steadily.This results in novel and unprecedented challenges,namely obesity and neurodegeneration.展开更多
Magnetic resonance imaging(MRI)is one of the most widely used diagnostic techniques.Iron oxide nanoparticles,as a promising kind of contrast agents,have attracted intense research interest due to their low toxicity an...Magnetic resonance imaging(MRI)is one of the most widely used diagnostic techniques.Iron oxide nanoparticles,as a promising kind of contrast agents,have attracted intense research interest due to their low toxicity and superparamagnetism.However,it is still a great challenge to prepare ideal iron oxide based contrast agents with high uniformity,excellent water solubility and biocompatibility.In this paper,a novel water-soluble polymer ligand pentaerythritol tetrakis 3-mercaptopropionate-poly(N-vinyl-2-pyrrolidone)(PTMP-PVP)was used as a capping reagent to prepare iron oxide nanoparticles MIONs@PTMP-PVP through one-step co-precipitation of iron precursors in aqueous solution at 100℃.The obtained nanoparticles MIONs@PTMP-PVP had a small size and narrow size distribution,and they were found to be biocompatible as determined through CCK-8 assay and histology analysis.In vivo MRI study demonstrated that the obtained MIONs@PTMP-PVP can be potentially used as an effective T_(2)-weighted MRI contrast agent.展开更多
Mesenchymal stromal cell transplantation is an effective and promising approach for treating various systemic and diffuse diseases.However,the biological characteristics of transplanted mesenchymal stromal cells in hu...Mesenchymal stromal cell transplantation is an effective and promising approach for treating various systemic and diffuse diseases.However,the biological characteristics of transplanted mesenchymal stromal cells in humans remain unclear,including cell viability,distribution,migration,and fate.Conventional cell tracing methods cannot be used in the clinic.The use of superparamagnetic iron oxide nanoparticles as contrast agents allows for the observation of transplanted cells using magnetic resonance imaging.In 2016,the National Medical Products Administration of China approved a new superparamagnetic iron oxide nanoparticle,Ruicun,for use as a contrast agent in clinical trials.In the present study,an acute hemi-transection spinal cord injury model was established in beagle dogs.The injury was then treated by transplantation of Ruicun-labeled mesenchymal stromal cells.The results indicated that Ruicunlabeled mesenchymal stromal cells repaired damaged spinal cord fibers and partially restored neurological function in animals with acute spinal cord injury.T2*-weighted imaging revealed low signal areas on both sides of the injured spinal cord.The results of quantitative susceptibility mapping with ultrashort echo time sequences indicated that Ruicun-labeled mesenchymal stromal cells persisted stably within the injured spinal cord for over 4 weeks.These findings suggest that magnetic resonance imaging has the potential to effectively track the migration of Ruicun-labeled mesenchymal stromal cells and assess their ability to repair spinal cord injury.展开更多
In the present research, the orthogonal experiment was carried out to investigate the influence of different austempering process parameters （i.e. austenitizing temperature and time, and austempering temperature and ...In the present research, the orthogonal experiment was carried out to investigate the influence of different austempering process parameters （i.e. austenitizing temperature and time, and austempering temperature and time） on microstructure and mechanical properties of LZQT500-7 ductile iron dense bars with 172 mm in diameter which were produced by horizontal continuous casting （HCC）. The results show that the major factors influencing the hardness of austempered ductile iron （ADI） are austenitizing temperature and austempering temperature. The fraction of retained austenite increases as the austenitizing and austempering temperatures increase. When austenitizing temperature is low, acicular ferrite and retained austenite can be efifciently obtained by appropriately extending the austenitizing time. The proper austmepering time could ensure enough stability of retained austenite and prevent high carbon austenite decomposition. The optimal mechanical properties of ADI can be achieved with the fol owing process parameters： austenitizing temperature and time are 866 ＆#176;C and 135 min, and austempering temperature and time are 279 ＆#176;C and 135 min, respectively. The microstructure of ADI under the optimal austempering process consists of ifne acicular ferrite and a smal amount of retained austenite, and the hardness, tensile strength, yield strength, elongation and impact toughness of the bars are HBW 476, 1670 MPa, 1428 MPa, 2.93%and 25.7 J, respectively.展开更多
Reducing the chloride content in regenerated iron oxides (RIO) from steel-pickling acid waste economically treated by Ruthner process is the most critical issue for the development of RIO as a useful raw material reso...Reducing the chloride content in regenerated iron oxides (RIO) from steel-pickling acid waste economically treated by Ruthner process is the most critical issue for the development of RIO as a useful raw material resource. In this paper, the results of a new method for characterization and modification of RIO produced in Mobarakeh Steel Complex were reported.展开更多
This study attempted to construct a three series barrier system to treat high concentrations of trichloroethylene （TCE; 500 mg/L） in synthetic groundwater. The system consisted of three reactive barriers using iron ...This study attempted to construct a three series barrier system to treat high concentrations of trichloroethylene （TCE; 500 mg/L） in synthetic groundwater. The system consisted of three reactive barriers using iron fillings as an iron-based barrier in the first column, sugarcane bagasse mixed with anaerobic sludge as an anaerobic barrier in the second column, and a biofilm coated on oxygen carbon inducer releasing material as an aerobic barrier in the third column. In order to evaluate the extent of removal of TCE and its metabolites in the aquifer down gradient of the barrier system, a fourth column filled with sand was applied. Residence time of the system was investigated by a bromide tracer test. The results showed that residence time in the column system of the control set and experimental set were 23.62 and 29.99 days, respectively. The efficiency of the three series barrier system in removing TCE was approximately 84% in which the removal efficiency of TCE by the iron filling barrier, anaerobic barrier and aerobic barrier were 42%, 16% and 25%, respectively. cis-Dichloroethylene （cis-DCE）, vinyl chloride （VC）, ethylene and chloride ions were observed as metabolites following TCE degradation. The presence of chloride ions in the effluent from the column system indicated the degradation of TCE. However, cis-DCE and VC were not fully degraded by the proposed barrier system which suggested that another remediation technology after the barrier treatment such as air sparging and adsorption by activated carbon should be conducted.展开更多
The application of nanoscale zero-valent iron(nZVI) for the degradation of contaminants has been extensively investigated, however, few studies have focused on degradation in high salinity environments. In this study,...The application of nanoscale zero-valent iron(nZVI) for the degradation of contaminants has been extensively investigated, however, few studies have focused on degradation in high salinity environments. In this study, the ability of bare and carboxymethyl cellulose(CMC)-coated bimetallic Pd-nZVI particles to degrade 33′44′-tetrachlorobiphenyl in high saline water(SW) is examined with particular attention given to the effects of ethylenediaminetetraacetic acid(EDTA) on the rate of degradation. EDTA enhances the reactivity of Pd-nZVI in SW, with evidence provided to link this to the removal of the passivating layer. Additionally, a conceptual model is proposed which provides a quantitative description of the removal of these iron oxide layers in the presence of EDTA. An optimum EDTA to bare Pd-nZVI molar ratio of 0.1 exists, with insufficient EDTA unable to remove the passivating layer whilst excess EDTA results in Fe loss and enhanced agglomeration due to magnetic attraction of the bare Fe(0) particles. In contrast, CMCcoating of Pd-nZVI assemblages actually impedes degradation, despite the coated particles displaying a smaller average size compared to uncoated particles, with even the presence of EDTA in this case not significantly improving degradation. The reduced reactivity in the presence of CMC is primarily attributed to the effect of CMC on the association of Pd with nZVI particles. In particular, the presence of CMC reduced the total amount of Pd incorporated with the stabilized particles compared to the non-stabilized particles.Additionally, the presence of CMC results in less Pd present in its reactive zero-valent oxidation state.展开更多
The revegetation of mined areas poses a great challenge to the iron ore mining industry.The initial recovery process in degraded areas might rely on the use of Fe-resistant grasses.Tropical grasses, such as Paspalum d...The revegetation of mined areas poses a great challenge to the iron ore mining industry.The initial recovery process in degraded areas might rely on the use of Fe-resistant grasses.Tropical grasses, such as Paspalum densum and Echinochloa crus-galli, show different resistance strategies to iron toxicity; however, these mechanisms are poorly understood.The Fe-resistance mechanisms and direct iron toxicity as a function of root apex removal were investigated. To achieve this purpose, both grass species were grown for up to 480 hr in a nutrient solution containing 0.019 or 7 mmol/L Fe-EDTA after the root apices had been removed or maintained. Cultivation in the presence of excess iron-induced leaf bronzing and the formation of iron plaque on the root surfaces of both grass species, but was more significant on those plants whose root apex had been removed. Iron accumulation was higher in the roots, but reached phytotoxic levels in the aerial parts as well. It did not hinder the biosynthesis of chloroplastidic pigments. No significant changes in gas exchange and chlorophyll a fluorescence occurred in either grass when their roots were kept intact; the contrary was true for plants with excised root apices. In both studied grasses, the root apoplastic barriers had an important function in the restriction of iron translocation from the root to the aerial plant parts, especially in E. crus-galli. Root apex removal negatively influenced the iron toxicity resistance mechanisms(tolerance in P. densum and avoidance in E. crus-galli).展开更多
Fe–S compounds with hexagonal crystal structure are potential hydrogen permeation barrier during H2S corrosion. Hexagonal system Fe–S films were prepared on carbon steel through corrosion and CVD deposition, and the...Fe–S compounds with hexagonal crystal structure are potential hydrogen permeation barrier during H2S corrosion. Hexagonal system Fe–S films were prepared on carbon steel through corrosion and CVD deposition, and the barrier effect of different Fe–S films on hydrogen permeation was tested using electrochemical hydrogen permeation method. After that, the electrical properties of Fe–S compound during phase transformation were measured using thermoelectric measurement system. Results show that the mackinawite has no obvious barrier effect on hydrogen penetration, as a p-type semiconductor, and pyrrhotite (including troilite) has obvious barrier effect on hydrogen penetration,as an n-type semiconductor. Hydrogen permeation tests showed peak permeation performance when the surface was deposited with a continuous film of pyrrhotite (Fe_(1–x)S) and troilite. The FeS compounds suppressed hydrogen permeation by the promotion of the hydrogen evolution reaction, semiconducting inversion from p-to n-type, and the migration of ions at the interface.展开更多
Objective To investigate the potential involvement of DMT1（IRE） protein in the brain vascular system in vivo during Pb exposure. Methods Three groups of male Sprague-Dawley rats were exposed to Pb in drinking water,...Objective To investigate the potential involvement of DMT1（IRE） protein in the brain vascular system in vivo during Pb exposure. Methods Three groups of male Sprague-Dawley rats were exposed to Pb in drinking water, among which two groups were concurrently administered by oral gavage once every other day as the low and high Fe treatment group, respectively, for 6 weeks. At the same time, the group only supplied with high Fe was also set as a reference. The animals were decapitated, then brain capillary-rich fraction was isolate from cerebral cortex. Western blot method was used to identify protein expression, and RT-PCR to detect the change of the m RNA. Results Pb exposure significantly increased Pb concentrations in cerebral cortex. Low Fe dose significantly reduced the cortex Pb levels, However, high Fe dose increased the cortex Pb levels. Interestingly, changes of DMT1（IRE） protein in brain capillary-rich fraction were highly related to the Pb level, but those of DMT1（IRE） m RNA were not significantly different. Moreover, the consistent changes in the levels of p-ERK1/2 or IRP1 with the changes in the levels of DMT1（IRE）. Conclusion These results suggest that Pb is transported into the brain through DMT1（IRE）, and the ERK MAPK pathway is involved in DMT1（IRE）-mediated transport regulation in brain vascular system in vivo.展开更多
The utilization of iron coke provides a green pathway for low-carbon ironmaking.To uncover the influence mechanism of iron ore on the behavior and kinetics of iron coke gasification,the effect of iron ore on the micro...The utilization of iron coke provides a green pathway for low-carbon ironmaking.To uncover the influence mechanism of iron ore on the behavior and kinetics of iron coke gasification,the effect of iron ore on the microstructure of iron coke was investigated.Furthermore,a comparative study of the gasification reactions between iron coke and coke was conducted through non-isothermal thermogravimetric method.The findings indicate that compared to coke,iron coke exhibits an augmentation in micropores and specific surface area,and the micropores further extend and interconnect.This provides more adsorption sites for CO_(2) molecules during the gasification process,resulting in a reduction in the initial gasification temperature of iron coke.Accelerating the heating rate in non-isothermal gasification can enhance the reactivity of iron coke.The metallic iron reduced from iron ore is embedded in the carbon matrix,reducing the orderliness of the carbon structure,which is primarily responsible for the heightened reactivity of the carbon atoms.The kinetic study indicates that the random pore model can effectively represent the gasification process of iron coke due to its rich pore structure.Moreover,as the proportion of iron ore increases,the activation energy for the carbon gasification gradually decreases,from 246.2 kJ/mol for coke to 192.5 kJ/mol for iron coke 15wt%.展开更多
Background:Anaemia during pregnancy is a major nutritional problem that can cause preterm delivery and low birth weight.Adherence to iron supplementation can prevent anaemia during pregnancy.However,adherence to iron ...Background:Anaemia during pregnancy is a major nutritional problem that can cause preterm delivery and low birth weight.Adherence to iron supplementation can prevent anaemia during pregnancy.However,adherence to iron supplementation remains a problem in many countries.Objective:This study aimed to identify the correlations of the perceived benefits and perceived barriers of and family support for iron supplementation with adherence to this practice amongst pregnant woman in Surabaya,Indonesia.Methods:A cross-sectional study was carried out on 102 pregnant women who attended check-ups at the Puskesmas and received iron supplementation.Data were collected using questionnaires.Results:Perceived benefits(r=0.334,P=0.001),perceived barriers(r=-0.294,P=0.003)and family support(r=0.263,P=0.008)were noted to be correlated with adherence to iron supplementation amongst pregnant woman in Surabaya,Indonesia.Conclusion:Perceived benefits,perceived barriers and family support are related to adherence to iron supplementation;thus,developing good perceptions and family support should be properly promoted.展开更多
Surface compositions of Fe3Si, FeSi and FeSi2 under 0.1 to 5ke V Ar+ bombaniment have been investigated by using AES method, and the results indicate that the sudece compositions depend strongly on ion enerpy and sam...Surface compositions of Fe3Si, FeSi and FeSi2 under 0.1 to 5ke V Ar+ bombaniment have been investigated by using AES method, and the results indicate that the sudece compositions depend strongly on ion enerpy and sample bulk compositions. While in FeSi and FeSi2 only Fe enrichment in the selvage has been observed, in Fe3Si it is Si enriched when the ion enerpy is higher than 31OeV Competition between preferential sputtering and radiation enhanced segmpation is quoted to eoplain this phenomenon.展开更多
基金financially supported by the Shaanxi Provincial Science and Technology Achievement Transfer and Promotion Plan-absorb Achievement Transformation Project(No.2017CGZH-XNGJ-03)Shaanxi Provincial Education Department Scientific Research Program Project-service Local Special Industrialization Cultivation Project(No.17JF018)+1 种基金Xi'an Science and Technology Planning Project Science and Technology Innovation Guide Projects(No.201805037YD15CG21(19))Xi'an University of Technology Scientific and Technological Achievement Transformation Project-technical Requirement Solving Project of Enterprises(No.2018-1)
文摘Ductile iron bars(DIBs) with a diameter of 145 mm, used for plunger pump production, were made by the horizontal continuous casting(HCC). The microstructure of the samples cut at three locations with different distances away from the surface(~20 mm from the surface, half of the radius and the center of the HCCDIBs)were investigated. The mechanical properties were measured by tensile and torsion tests. Results show that after the spheroidization of graphite, the iron matrix incorporates the nodules of Format I, Size 8 close to the surface, Format I, Size 7 at the half of the radius from the surface, and Format II, Size 6 in the centre of the bar,according to the ASTM A247 standard. The content of pearlite in the matrix changes from 55%(~20 mm from the surface) to 70%(half of the radius) and 80%(the center of the HCCDIBs). The strengths in tension are 552, 607 and 486 MPa with the elongations of 12.5%, 10.5% and 5.8% in samples cut at these three locations from the surface to the centre, respectively. The strength in torsion is equal to 558, 551 and 471 MPa at corresponding torsion angles of 418°, 384° and 144° respectively to the same distance from the bar surface. Fracture in tension is manifested via crack propagation through the interface between graphite nodules and matrix(Mode I), while in torsion the fracture is caused by the shear of graphite nodules(Mode II). It is shown that the transition between two fracture modes is also dependent on the size of graphite nodule. Typically, fracture Mode I was observed for nodules of smaller diameter(less than 22.7 μm) and fracture Mode II was seen for nodules of greater diameter(more than 24.8 μm).
文摘The solidification process of a horizontally continuously cast gray iron bar of 4.6cm in diame- ter was modelled.The function describing the distribution of heat flux at the internal surface of graphite sleeve,which was equal to that on the surface of the iron bar,was inversely derived using numerical calculation from the temperature distribution in the sleeve measured in real production.By using the distribution of heat flux as a boundary condition on the surface of the iron bar,the numerical simulation on solidification of the iron bar taking longitudinal heat conduction into account was made.The profile of solidification front obtained from the numer- ical simulation was approximately coincident with that in real production.In addition,the quantitative relationships of the thickness of solidified shell at the exit of the mold to the main technological parameters,including the temperature of liquid iron at the entrance of the mold, the moving speed of the bar and the intensity of water cooling,were obtained from the numeri- cal simulation.
基金supported by the National Natural Science Foundation of China(No.52274344)the Provincial Natural Science Foundation of Hunan(Nos.2022JJ30723 and 2023JJ20068)the Science and Technology Innovation Program of Hunan Province(2023RC3042).
文摘Controlling the adhesion of potentially corrosive substances from flue gas on grate bar is crucial for extending the operational lifespan of the equipment.The adhesive behaviour and mechanism of ultrafine particulate matters(UPM)throughout the sintering process were elucidated,and measures to control adhesion on grate bars were developed.Research findings indicated that a small quantity of UPM were found on grate bar during the initial sintering stages(ignition stage and middle stageⅠandⅡ).The main compositions of UPM were FexOy-rich,CaO-rich,and aluminium silicate-rich particles.In contrast,corrosive substances like alkali metal compounds were almost absent.These UPM adhered onto grate bar primarily through inertial impaction.When moving to the final sintering stages(middle stageⅢand temperature rising stage),many UPM rich in corrosive substances like NaCl and KCl adhered to the grate bar.These UPM adhered to grate bar through thermal diffusion and vortex deposition.Solid waste water washing technology can greatly decrease the quantity of UPM(rich in NaCl and KCl)on the grate bar due to vortex deposition and thermal diffusion,and it represents a potentially promising way to control adhesion and corrosion on grate bars.
文摘Iron deficiency anemia affects approximately 1.62 billion people worldwide,yet traditional iron supplements present bioavailability limitations and gastrointestinal side effects.This randomized,double-blind clinical trial investigated a novel Auricularia auricula polysaccharide-iron complex(AAPIC)compared with heme iron and ferrous glycinate in 180 iron-deficient adults receiving 30 mg elemental iron daily for 12 weeks.AAPIC achieved comparable hemoglobin improvements(from 98.3±8.7 to 126.5±9.2 g/L)to heme iron(from 97.8±9.1 to 128.3±8.6 g/L)and was significantly superior to ferrous glycinate(from 98.6±8.9 to 119.7±10.3 g/L;p<0.001).Iron absorption efficiency showed AAPIC at 23.7±4.2%,heme iron at 25.1±3.8%,and ferrous glycinate at 18.4±5.1%.Toxicological assessments revealed no hepatotoxicity,nephrotoxicity,or mutagenicity.Gastrointestinal adverse events occurred in 8.3%of AAPIC recipients versus 15.0%with ferrous glycinate and 10.0%with heme iron.The polysaccharide component facilitates iron transport through enhanced intestinal uptake mechanisms.AAPIC represents a promising,well-tolerated alternative with clinical efficacy comparable to established iron formulations.
基金supported in part by the National Natural Science Foundation of China,No.82371153(to YS)the Natural Science Foundation of Shandong Province,Nos.ZR2021MH378,ZR2022QH073(to LC)+1 种基金the Shandong Society of Geriatric Science and Technology Project,No.LKJGG2021Z020(to YS)the Yantai Science and Technology Innovation Development Project,Nos.2022YD009,2023YD050。
文摘Neurodegenerative diseases are prevalent conditions that greatly impact human health.These diseases are primarily characterized by the progressive loss and eventual death of neuronal function,although the precise mechanisms underlying these processes remain incompletely understood.Iron is an essential trace element in the human body,playing a crucial role in various biological processes.The maintenance of iron homeostasis relies on the body's intricate and nuanced regulatory mechanisms.In recent years,considerable attention has been directed toward the relationship between dysregulated iron homeostasis and neurodegenerative diseases.The regulation of iron homeostasis within cells is crucial for maintaining proper nervous system function.Research has already revealed that disruptions in iron homeostasis may lead to ferroptosis and oxidative stress,which,in turn,can impact neuronal health and contribute to the development of neurodegenerative diseases.This article primarily explores the intimate relationship between iron homeostasis and neurodegenerative diseases,aiming to provide novel insights and strategies for treating these debilitating conditions.
基金financially supported by the National Natural Science Foundation of China(52130109)。
文摘Centrifugal casting of ductile iron pipe is a high-temperature,semi-continuous production process.However,conducting laboratory research on the solidification process of centrifugal casting of ductile iron pipe presents significant challenges.In this study,a novel research method was introduced for investigating the solidification process of ductile iron pipe,namely thermal simulation of ductile iron pipe.Comparative research was conducted on the microstructure and properties of the thermal simulation sample and the ductile iron pipe.The findings indicate that the thermal simulation sample and ductile iron pipe exhibit good heat transfer similarity and microstructure similarity.The difference of cooling rate between thermal simulation sample and ductile pipe is less than 0.24℃·s^(-1),and the difference of microstructure content of free cementite,ferrite,and pearlite is less than 5%.The tensile strength of annealed ductile iron pipe is 466 MPa,with an elongation of 16.1%and a Brinell hardness of 156.5 HBW.In comparison,the tensile strength of annealed thermal simulation sample is 482.0 MPa,with an elongation of 15.5%and a Brinell hardness of 159.0 HBW.These results suggest that the thermal simulation experimental research method is both scientific and feasible,offering an objective,reliable,and cost-effective approach to laboratory research on ductile iron pipe.
文摘With the industrialization of agriculture and the advancement of medical care,human life expectancy has increased considerably and continues to rise steadily.This results in novel and unprecedented challenges,namely obesity and neurodegeneration.
基金financially supported by the International Cooperation Program from the Ministry of Science and Technology of Hubei Province(No.2023EHA069)Shenzhen Science and Technology Program(No.JCYJ20230807143702005)National Foreign Experts Program(No.G2022027015L)。
文摘Magnetic resonance imaging(MRI)is one of the most widely used diagnostic techniques.Iron oxide nanoparticles,as a promising kind of contrast agents,have attracted intense research interest due to their low toxicity and superparamagnetism.However,it is still a great challenge to prepare ideal iron oxide based contrast agents with high uniformity,excellent water solubility and biocompatibility.In this paper,a novel water-soluble polymer ligand pentaerythritol tetrakis 3-mercaptopropionate-poly(N-vinyl-2-pyrrolidone)(PTMP-PVP)was used as a capping reagent to prepare iron oxide nanoparticles MIONs@PTMP-PVP through one-step co-precipitation of iron precursors in aqueous solution at 100℃.The obtained nanoparticles MIONs@PTMP-PVP had a small size and narrow size distribution,and they were found to be biocompatible as determined through CCK-8 assay and histology analysis.In vivo MRI study demonstrated that the obtained MIONs@PTMP-PVP can be potentially used as an effective T_(2)-weighted MRI contrast agent.
基金supported by the National Key R&D Program of China,Nos.2017YFA0104302(to NG and XM)and 2017YFA0104304(to BW and ZZ)
文摘Mesenchymal stromal cell transplantation is an effective and promising approach for treating various systemic and diffuse diseases.However,the biological characteristics of transplanted mesenchymal stromal cells in humans remain unclear,including cell viability,distribution,migration,and fate.Conventional cell tracing methods cannot be used in the clinic.The use of superparamagnetic iron oxide nanoparticles as contrast agents allows for the observation of transplanted cells using magnetic resonance imaging.In 2016,the National Medical Products Administration of China approved a new superparamagnetic iron oxide nanoparticle,Ruicun,for use as a contrast agent in clinical trials.In the present study,an acute hemi-transection spinal cord injury model was established in beagle dogs.The injury was then treated by transplantation of Ruicun-labeled mesenchymal stromal cells.The results indicated that Ruicunlabeled mesenchymal stromal cells repaired damaged spinal cord fibers and partially restored neurological function in animals with acute spinal cord injury.T2*-weighted imaging revealed low signal areas on both sides of the injured spinal cord.The results of quantitative susceptibility mapping with ultrashort echo time sequences indicated that Ruicun-labeled mesenchymal stromal cells persisted stably within the injured spinal cord for over 4 weeks.These findings suggest that magnetic resonance imaging has the potential to effectively track the migration of Ruicun-labeled mesenchymal stromal cells and assess their ability to repair spinal cord injury.
基金financially supported by the fund of the Key Projects of Shaanxi Provincial International Technology Cooperation Plan(2013KW16)the Scientific Research Program funded by Shaanxi Provincial Education Department(2013JK0914)+2 种基金the State Key Laboratory of Solidifi cation Processing in NWPU(SKLSP201115)the Scientific Research Project of Xi'an University of Technology(2013CX004)the fund of the Key Laboratory of Electrical Materials and Infi ltration Technology of Shaanxi Province,China(2014)
文摘In the present research, the orthogonal experiment was carried out to investigate the influence of different austempering process parameters （i.e. austenitizing temperature and time, and austempering temperature and time） on microstructure and mechanical properties of LZQT500-7 ductile iron dense bars with 172 mm in diameter which were produced by horizontal continuous casting （HCC）. The results show that the major factors influencing the hardness of austempered ductile iron （ADI） are austenitizing temperature and austempering temperature. The fraction of retained austenite increases as the austenitizing and austempering temperatures increase. When austenitizing temperature is low, acicular ferrite and retained austenite can be efifciently obtained by appropriately extending the austenitizing time. The proper austmepering time could ensure enough stability of retained austenite and prevent high carbon austenite decomposition. The optimal mechanical properties of ADI can be achieved with the fol owing process parameters： austenitizing temperature and time are 866 ＆#176;C and 135 min, and austempering temperature and time are 279 ＆#176;C and 135 min, respectively. The microstructure of ADI under the optimal austempering process consists of ifne acicular ferrite and a smal amount of retained austenite, and the hardness, tensile strength, yield strength, elongation and impact toughness of the bars are HBW 476, 1670 MPa, 1428 MPa, 2.93%and 25.7 J, respectively.
文摘Reducing the chloride content in regenerated iron oxides (RIO) from steel-pickling acid waste economically treated by Ruthner process is the most critical issue for the development of RIO as a useful raw material resource. In this paper, the results of a new method for characterization and modification of RIO produced in Mobarakeh Steel Complex were reported.
基金the travel funds from Rajamangala University of Technology-Isan-Kalasin Campus and the GraduateSchool,Khon Kaen University
文摘This study attempted to construct a three series barrier system to treat high concentrations of trichloroethylene （TCE; 500 mg/L） in synthetic groundwater. The system consisted of three reactive barriers using iron fillings as an iron-based barrier in the first column, sugarcane bagasse mixed with anaerobic sludge as an anaerobic barrier in the second column, and a biofilm coated on oxygen carbon inducer releasing material as an aerobic barrier in the third column. In order to evaluate the extent of removal of TCE and its metabolites in the aquifer down gradient of the barrier system, a fourth column filled with sand was applied. Residence time of the system was investigated by a bromide tracer test. The results showed that residence time in the column system of the control set and experimental set were 23.62 and 29.99 days, respectively. The efficiency of the three series barrier system in removing TCE was approximately 84% in which the removal efficiency of TCE by the iron filling barrier, anaerobic barrier and aerobic barrier were 42%, 16% and 25%, respectively. cis-Dichloroethylene （cis-DCE）, vinyl chloride （VC）, ethylene and chloride ions were observed as metabolites following TCE degradation. The presence of chloride ions in the effluent from the column system indicated the degradation of TCE. However, cis-DCE and VC were not fully degraded by the proposed barrier system which suggested that another remediation technology after the barrier treatment such as air sparging and adsorption by activated carbon should be conducted.
基金funding provided by the Hundred Talent Program of Guangdong University of Technology,China(No.220418134)the National Natural Science Foundation of China(No.41807349)the Australian Research Council through Linkage Project(No.LP100100852)
文摘The application of nanoscale zero-valent iron(nZVI) for the degradation of contaminants has been extensively investigated, however, few studies have focused on degradation in high salinity environments. In this study, the ability of bare and carboxymethyl cellulose(CMC)-coated bimetallic Pd-nZVI particles to degrade 33′44′-tetrachlorobiphenyl in high saline water(SW) is examined with particular attention given to the effects of ethylenediaminetetraacetic acid(EDTA) on the rate of degradation. EDTA enhances the reactivity of Pd-nZVI in SW, with evidence provided to link this to the removal of the passivating layer. Additionally, a conceptual model is proposed which provides a quantitative description of the removal of these iron oxide layers in the presence of EDTA. An optimum EDTA to bare Pd-nZVI molar ratio of 0.1 exists, with insufficient EDTA unable to remove the passivating layer whilst excess EDTA results in Fe loss and enhanced agglomeration due to magnetic attraction of the bare Fe(0) particles. In contrast, CMCcoating of Pd-nZVI assemblages actually impedes degradation, despite the coated particles displaying a smaller average size compared to uncoated particles, with even the presence of EDTA in this case not significantly improving degradation. The reduced reactivity in the presence of CMC is primarily attributed to the effect of CMC on the association of Pd with nZVI particles. In particular, the presence of CMC reduced the total amount of Pd incorporated with the stabilized particles compared to the non-stabilized particles.Additionally, the presence of CMC results in less Pd present in its reactive zero-valent oxidation state.
基金supported by Vale S.A. (No. ACA 5500023606/ 5900022781)the National Council for Scientific and Technological Development - CNPq (No. 311532/2017-9)the Minas Gerais Research Foundation - FAPEMIG
文摘The revegetation of mined areas poses a great challenge to the iron ore mining industry.The initial recovery process in degraded areas might rely on the use of Fe-resistant grasses.Tropical grasses, such as Paspalum densum and Echinochloa crus-galli, show different resistance strategies to iron toxicity; however, these mechanisms are poorly understood.The Fe-resistance mechanisms and direct iron toxicity as a function of root apex removal were investigated. To achieve this purpose, both grass species were grown for up to 480 hr in a nutrient solution containing 0.019 or 7 mmol/L Fe-EDTA after the root apices had been removed or maintained. Cultivation in the presence of excess iron-induced leaf bronzing and the formation of iron plaque on the root surfaces of both grass species, but was more significant on those plants whose root apex had been removed. Iron accumulation was higher in the roots, but reached phytotoxic levels in the aerial parts as well. It did not hinder the biosynthesis of chloroplastidic pigments. No significant changes in gas exchange and chlorophyll a fluorescence occurred in either grass when their roots were kept intact; the contrary was true for plants with excised root apices. In both studied grasses, the root apoplastic barriers had an important function in the restriction of iron translocation from the root to the aerial plant parts, especially in E. crus-galli. Root apex removal negatively influenced the iron toxicity resistance mechanisms(tolerance in P. densum and avoidance in E. crus-galli).
基金financailly supported by the National Natural Science Foundation of China (Nos.52275198 and 51805292)the Beijing Natural Science Foundation,China(No.2202020)the Tribology Science Fund of State Key Laboratory of Tribology,China (No.SKLT2022B11)。
文摘Fe–S compounds with hexagonal crystal structure are potential hydrogen permeation barrier during H2S corrosion. Hexagonal system Fe–S films were prepared on carbon steel through corrosion and CVD deposition, and the barrier effect of different Fe–S films on hydrogen permeation was tested using electrochemical hydrogen permeation method. After that, the electrical properties of Fe–S compound during phase transformation were measured using thermoelectric measurement system. Results show that the mackinawite has no obvious barrier effect on hydrogen penetration, as a p-type semiconductor, and pyrrhotite (including troilite) has obvious barrier effect on hydrogen penetration,as an n-type semiconductor. Hydrogen permeation tests showed peak permeation performance when the surface was deposited with a continuous film of pyrrhotite (Fe_(1–x)S) and troilite. The FeS compounds suppressed hydrogen permeation by the promotion of the hydrogen evolution reaction, semiconducting inversion from p-to n-type, and the migration of ions at the interface.
基金supported by National Natural Science Foundation of China(No.81472478)Medical Science Youth Breeding Project of PLA(13QNP161)
文摘Objective To investigate the potential involvement of DMT1（IRE） protein in the brain vascular system in vivo during Pb exposure. Methods Three groups of male Sprague-Dawley rats were exposed to Pb in drinking water, among which two groups were concurrently administered by oral gavage once every other day as the low and high Fe treatment group, respectively, for 6 weeks. At the same time, the group only supplied with high Fe was also set as a reference. The animals were decapitated, then brain capillary-rich fraction was isolate from cerebral cortex. Western blot method was used to identify protein expression, and RT-PCR to detect the change of the m RNA. Results Pb exposure significantly increased Pb concentrations in cerebral cortex. Low Fe dose significantly reduced the cortex Pb levels, However, high Fe dose increased the cortex Pb levels. Interestingly, changes of DMT1（IRE） protein in brain capillary-rich fraction were highly related to the Pb level, but those of DMT1（IRE） m RNA were not significantly different. Moreover, the consistent changes in the levels of p-ERK1/2 or IRP1 with the changes in the levels of DMT1（IRE）. Conclusion These results suggest that Pb is transported into the brain through DMT1（IRE）, and the ERK MAPK pathway is involved in DMT1（IRE）-mediated transport regulation in brain vascular system in vivo.
基金financially supported by the National Science Foundation of China(Nos.51974212 and 52274316)the China Baowu Low Carbon Metallurgy Innovation Foundation(No.BWLCF202116)+1 种基金the Science and Technology Major Project of Wuhan(No.2023020302020572)the Foundation of Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education(No.FMRUlab23-04)。
文摘The utilization of iron coke provides a green pathway for low-carbon ironmaking.To uncover the influence mechanism of iron ore on the behavior and kinetics of iron coke gasification,the effect of iron ore on the microstructure of iron coke was investigated.Furthermore,a comparative study of the gasification reactions between iron coke and coke was conducted through non-isothermal thermogravimetric method.The findings indicate that compared to coke,iron coke exhibits an augmentation in micropores and specific surface area,and the micropores further extend and interconnect.This provides more adsorption sites for CO_(2) molecules during the gasification process,resulting in a reduction in the initial gasification temperature of iron coke.Accelerating the heating rate in non-isothermal gasification can enhance the reactivity of iron coke.The metallic iron reduced from iron ore is embedded in the carbon matrix,reducing the orderliness of the carbon structure,which is primarily responsible for the heightened reactivity of the carbon atoms.The kinetic study indicates that the random pore model can effectively represent the gasification process of iron coke due to its rich pore structure.Moreover,as the proportion of iron ore increases,the activation energy for the carbon gasification gradually decreases,from 246.2 kJ/mol for coke to 192.5 kJ/mol for iron coke 15wt%.
基金This study was supported by the Universitas Airlangga Surabaya.
文摘Background:Anaemia during pregnancy is a major nutritional problem that can cause preterm delivery and low birth weight.Adherence to iron supplementation can prevent anaemia during pregnancy.However,adherence to iron supplementation remains a problem in many countries.Objective:This study aimed to identify the correlations of the perceived benefits and perceived barriers of and family support for iron supplementation with adherence to this practice amongst pregnant woman in Surabaya,Indonesia.Methods:A cross-sectional study was carried out on 102 pregnant women who attended check-ups at the Puskesmas and received iron supplementation.Data were collected using questionnaires.Results:Perceived benefits(r=0.334,P=0.001),perceived barriers(r=-0.294,P=0.003)and family support(r=0.263,P=0.008)were noted to be correlated with adherence to iron supplementation amongst pregnant woman in Surabaya,Indonesia.Conclusion:Perceived benefits,perceived barriers and family support are related to adherence to iron supplementation;thus,developing good perceptions and family support should be properly promoted.
文摘Surface compositions of Fe3Si, FeSi and FeSi2 under 0.1 to 5ke V Ar+ bombaniment have been investigated by using AES method, and the results indicate that the sudece compositions depend strongly on ion enerpy and sample bulk compositions. While in FeSi and FeSi2 only Fe enrichment in the selvage has been observed, in Fe3Si it is Si enriched when the ion enerpy is higher than 31OeV Competition between preferential sputtering and radiation enhanced segmpation is quoted to eoplain this phenomenon.
