Single event effects of 1-T structure programmable read-only memory(PROM) devices fabricated with a 130-nm complementary metal oxide semiconductorbased thin/thick gate oxide anti-fuse process were investigated using h...Single event effects of 1-T structure programmable read-only memory(PROM) devices fabricated with a 130-nm complementary metal oxide semiconductorbased thin/thick gate oxide anti-fuse process were investigated using heavy ions and a picosecond pulsed laser. The cross sections of a single event upset(SEU) for radiationhardened PROMs were measured using a linear energy transfer(LET) ranging from 9.2 to 95.6 MeV cm^2mg^(-1).The result indicated that the LET threshold for a dynamic bit upset was ~ 9 MeV cm^2mg^(-1), which was lower than the threshold of ~ 20 MeV cm^2mg^(-1) for an address counter upset owing to the additional triple modular redundancy structure present in the latch. In addition, a slight hard error was observed in the anti-fuse structure when employing209 Bi ions with extremely high LET values(~ 91.6 MeV cm^2mg^(-1)) and large ion fluence(~ 1×10~8 ions cm^(-2)). To identify the detailed sensitive position of a SEU in PROMs, a pulsed laser with a 5-μm beam spot was used to scan the entire surface of the device.This revealed that the upset occurred in the peripheral circuits of the internal power source and I/O pairs rather than in the internal latches and buffers. This was subsequently confirmed by a ^(181)Ta experiment. Based on the experimental data and a rectangular parallelepiped model of the sensitive volume, the space error rates for the used PROMs were calculated using the CRèME-96 prediction tool. The results showed that this type of PROM was suitable for specific space applications, even in the geosynchronous orbit.展开更多
The co-reduction roasting and grinding-magnetic separation of seaside titanomagnetite and blast furnace dust was investigated with and without fluorite addition at a reduction roasting temperature of 1250°C for 6...The co-reduction roasting and grinding-magnetic separation of seaside titanomagnetite and blast furnace dust was investigated with and without fluorite addition at a reduction roasting temperature of 1250°C for 60 min, a grinding fineness of-43 μm accounting for 69.02 wt% of the total, and a low-intensity magnetic field strength of 151 kA/m. The mineral composition, microstructure, and state of the roasted products were analyzed, and the concentrations of CO and CO_2 were analyzed in the co-reduction roasting. Better results were achieved with a small fluorite dosage(≤4 wt%) in the process of co-reduction. In addition, F^- was found to reduce the melting point and viscosity of the slag phase because of the high content of aluminate and silicate minerals in the blast furnace dust. The low moisture content of the blast furnace dust and calcic minerals inhibited the hydrolysis of CaF_2 and the loss of F^-. Compared with the blast furnace dust from Chengdeng, the blast furnace dusts from Jiugang and Jinxin inhibited the diffusion of F-when used as reducing agents, leading to weaker effects of fluorite.展开更多
As a national policy of benefiting the country and the people, " precision" poverty alleviation has an important strategic position.The core of " precision" poverty alleviation is education poverty...As a national policy of benefiting the country and the people, " precision" poverty alleviation has an important strategic position.The core of " precision" poverty alleviation is education poverty alleviation. Based on the background of " precision" poverty alleviation,this study focuses on the analysis of problems of rural inclusive private kindergartens in the province,such as the shortage of rural pre-school resources,the uneven quality of teachers,and lack of financial investment. And in view of the existing problems,this paper puts forward some solutions to better promote the rural inclusive kindergarten development in the province.展开更多
Rechargeable potassium-ion batteries(PIBs)have great potential in the application of electrochemical energy storage devices due to the low cost,the abundant resources and the low standard reduction potential of potass...Rechargeable potassium-ion batteries(PIBs)have great potential in the application of electrochemical energy storage devices due to the low cost,the abundant resources and the low standard reduction potential of potassium.As electrode materials are the key factors to determine the electrochemical performance of devices,relevant research is being carried out to build high-performance PIBs.In recent years,significant progress has been made in the study of the design of inorganic electrode materials.Herein,we review the cathode materials(Prussian blue and its analogues,layered oxides and poly anionic compounds)and the anode materials(antimony-based,selenium-based and bismuth-based compounds).On the basis of previous work,the structural design principles for improving the performance of electrode materials are reasonably summarized.At the same time,the problems that need to be solved in the preparation of electrode materials and the direction of future research and improvement are pointed out.展开更多
Virtual Shack-Hartmann wavefront sensing(vSHWS)has some significant advantages and is promising for aberration measurement in the field of biomedical optical imaging.The illumination sources used in vSHWS are almost b...Virtual Shack-Hartmann wavefront sensing(vSHWS)has some significant advantages and is promising for aberration measurement in the field of biomedical optical imaging.The illumination sources used in vSHWS are almost broadband,but are treated as monochromatic sources(only using center wavelength)in current data processing,which may cause errors.This work proposed a data processing method to take into account the multiple wavelengths of the broadband spectrum,named multiple-wavelength centroid-weighting method.Its feasibility was demonstrated through a series of simulations.A wavefront generated with a set of statistical human ocular aberrations was used as the target wavefront to evaluate the performance of the proposed and current methods.The results showed that their performance was very close when used for the symmetrical,but the wavefront error of the proposed method was much smaller than that of the current method when used for the asymmetrical spectrum,especially for the broader spectrum.These results were also validated by using 20 sets of clinical human ocular aberrations including normal and diseased eyes.The proposed method and the obtained conclusions have important implications for the application of vSHWS.展开更多
A technique comprising coal-based direct reduction followed by magnetic separation was presented to recover iron and copper from copper slag flotation tailings.Optimal process parameters,such as reductant and additive...A technique comprising coal-based direct reduction followed by magnetic separation was presented to recover iron and copper from copper slag flotation tailings.Optimal process parameters,such as reductant and additive ratios,reduction temperature,and reduction time,were experimentally determined and found to be as follows:a limestone ratio of 25%,a bitumite ratio of 30%,and reduction roasting at 1473 Kfor 90 min.Under these conditions,copper-bearing iron powders(CIP)with an iron content of 90.11% and copper content of 0.86%,indicating iron and copper recoveries of87.25% and 83.44%respectively,were effectively obtained.Scanning electron microscopy and energy dispersive spectroscopy of the CIP revealed that some tiny copper particles were embedded in metal iron and some copper formed alloy with iron,which was difficult to achieve the separation of these two metals.Thus,the copper went into magnetic products by magnetic separation.Adding copper into the steel can produce weathering steel.Therefore,the CIP can be used as an inexpensive raw material for weathering steel.展开更多
In this study, treatment of C57 BL/6 J(wild type, WT) mice fed a high-fat diet(HFD) with retinoic acid(RA) decreased body weight and subcutaneous and visceral fat content, reversed the apparent hepatosteatosis, and re...In this study, treatment of C57 BL/6 J(wild type, WT) mice fed a high-fat diet(HFD) with retinoic acid(RA) decreased body weight and subcutaneous and visceral fat content, reversed the apparent hepatosteatosis, and reduced hepatic intracellular triglyceride and serum alanine transaminase(ALT) and aspartate aminotransferase(AST) concentrations. Moreover, RA treatment improved glucose tolerance and insulin sensitivity in WT mice fed a HFD. However, these RA-induced effects in WT mice fed a HFD were alleviated in liver specific Sirtuin 1(Sirt1) deficient(LKO) mice fed a HFD. Furthermore,RA also could not improve glucose tolerance and insulin sensitivity in LKO mice fed a HFD. The mechanism studies indicated that RA indeed increased the expression of hepatic Sirt1 and superoxide dismutase 2(Sod2), and inhibited the expression of sterol regulatory element binding protein 1 c(Srebp-1 c) in WT mice in vivo and in vitro. RA decreased mitochondrial reactive oxygen species(ROS) production in WT primary hepatocytes and increased mitochondrial DNA(mtDNA) copy number in WT mice liver. However, these RA-mediated molecular effects were also abolished in the liver and primary hepatocytes from LKO mice. In summary, RA protected against HFD-induced hepato steatosis by decreasing Srebp-1 c expression and improving antioxidant capacity through a Sirtl-mediated mechanism.展开更多
Embedding direct reduction followed by magnetic separation was conducted to fully recover iron and titanium separately from beach titanomagnetite (TTM). The influences of reduction conditions, such as molar ratio of...Embedding direct reduction followed by magnetic separation was conducted to fully recover iron and titanium separately from beach titanomagnetite (TTM). The influences of reduction conditions, such as molar ratio of C to Fe, reduction time, and reduction temperature, were studied. The results showed that the TTM concentrate was reduced to iron and iron-titanium oxides, depending on the reduction time, and the reduction sequence at 1 200℃ was suggested as follows : Fe2.75 Ti0.25O4→Fe2TiO4→FeTiO3→FeTi2O5. The reduction temperature played a considerable role in the reduction of TTM concentrates. Increasing temperature from 1 100 to 1 200℃ was beneficial to recovering titanium and iron, whereas the results deteriorated as temperature increased further. The results of X-ray diffraction and scanning electron microscopy analyses showed that low temperature (≤1100℃) was unfavorable for the gasification of reductant, resulting in insufficient reducing atmosphere in the reduction process. The molten phase was formed at high temperatures of 1250-1 300℃, which accelerated the migration rate of metallic particles and suppressed the diffusion of reduction gas, resulting in poor reduction. The optimum conditions for reducing TTM concentrate are as follows: molar ratio of C to Fe of 1.68, reduction time of 150 min, and reduction temperature of 1 200℃. Under these conditions, direct reduction iron powder, assaying 90.28 mass% TFe and 1.73 mass% TiO2 with iron recovery of 90.85%, and titanium concentrate, assaying 46.24 mass% TiO2 with TiO2 recovery of 91.15%, were obtained.展开更多
The effect of sodium sulfate on direct reduction of beach titanomagnetite,followed by magnetic separation,to separate iron and titanium was investigated. Direct reduced iron( DRI) with a high Fe content,low TiO_2 co...The effect of sodium sulfate on direct reduction of beach titanomagnetite,followed by magnetic separation,to separate iron and titanium was investigated. Direct reduced iron( DRI) with a high Fe content,low TiO_2 content and low iron recovery was obtained after adding sodium sulfate. When the sodium sulfate dosage was increased from 0 to 10 mass%,the Fe content of the DRI increased from 90. 00 mass% to 93. 55 mass% and the TiO_2 content decreased from 1. 27 mass% to 0. 70 mass%. The reduction mechanism of sodium sulfate was investigated by X-ray diffraction( XRD) and scanning electron microscopy( SEM) with energy dispersive spectrometer( EDS). Results revealed that the metallic iron grains in the reduced ore with sodium sulfate were larger than those in the ore without sodium sulfate. Sodium sulfate promoted the migration of iron as well as the accumulation and growth of metallic iron grains by low-melting-point carnegieite and troilite formed in the redox system. Low-melting-point carnegieite decreased the melting point of the system and then promoted liquefaction. Troilite could decrease the surface tension and melting point of metallic iron grains.展开更多
Graphene/silicon(Gr/Si)Schottky barrier solar cells(SBSCs)are attractive for harvesting solar energy and have been gaining grounds for its low-cost solution-processing.The interfacial barrier between graphene and sili...Graphene/silicon(Gr/Si)Schottky barrier solar cells(SBSCs)are attractive for harvesting solar energy and have been gaining grounds for its low-cost solution-processing.The interfacial barrier between graphene and silicon facilitates the reducing excessive carrier recombination while accelerating the separation processes of photo-generated carriers at the interface,which empowers the performance of Gr/Si SBSCs.However,the difficulty to control the interface thickness prevents its application.Here,we introduce the graphene oxide quantum dots(GOQDs)as a unique interfacial modulation species with tunable thickness by controlling the GOQDs particle size.The power conversion efficiency(PCE)of 13.67%for Gr/Si-based SBSC with outstanding stability in the air is obtained with the optimal barrier thickness(26 nm)and particle size(4.15 nm)of GOQDs.The GOQDs in Gr/Si-based SBSCs provide the extra band bending which further enhances the PCE for its photovoltaic applications.展开更多
基金supported by the National Natural Science Foundation of China(Nos.11690041,11805244,and 11675233)the Opening Project of Science and Technology on Reliability Physics and Application Technology of the Electronic Component Laboratory(No.ZHD 201604)
文摘Single event effects of 1-T structure programmable read-only memory(PROM) devices fabricated with a 130-nm complementary metal oxide semiconductorbased thin/thick gate oxide anti-fuse process were investigated using heavy ions and a picosecond pulsed laser. The cross sections of a single event upset(SEU) for radiationhardened PROMs were measured using a linear energy transfer(LET) ranging from 9.2 to 95.6 MeV cm^2mg^(-1).The result indicated that the LET threshold for a dynamic bit upset was ~ 9 MeV cm^2mg^(-1), which was lower than the threshold of ~ 20 MeV cm^2mg^(-1) for an address counter upset owing to the additional triple modular redundancy structure present in the latch. In addition, a slight hard error was observed in the anti-fuse structure when employing209 Bi ions with extremely high LET values(~ 91.6 MeV cm^2mg^(-1)) and large ion fluence(~ 1×10~8 ions cm^(-2)). To identify the detailed sensitive position of a SEU in PROMs, a pulsed laser with a 5-μm beam spot was used to scan the entire surface of the device.This revealed that the upset occurred in the peripheral circuits of the internal power source and I/O pairs rather than in the internal latches and buffers. This was subsequently confirmed by a ^(181)Ta experiment. Based on the experimental data and a rectangular parallelepiped model of the sensitive volume, the space error rates for the used PROMs were calculated using the CRèME-96 prediction tool. The results showed that this type of PROM was suitable for specific space applications, even in the geosynchronous orbit.
基金financially supported by the National Natural Science Foundation of China (No. 51474018)
文摘The co-reduction roasting and grinding-magnetic separation of seaside titanomagnetite and blast furnace dust was investigated with and without fluorite addition at a reduction roasting temperature of 1250°C for 60 min, a grinding fineness of-43 μm accounting for 69.02 wt% of the total, and a low-intensity magnetic field strength of 151 kA/m. The mineral composition, microstructure, and state of the roasted products were analyzed, and the concentrations of CO and CO_2 were analyzed in the co-reduction roasting. Better results were achieved with a small fluorite dosage(≤4 wt%) in the process of co-reduction. In addition, F^- was found to reduce the melting point and viscosity of the slag phase because of the high content of aluminate and silicate minerals in the blast furnace dust. The low moisture content of the blast furnace dust and calcic minerals inhibited the hydrolysis of CaF_2 and the loss of F^-. Compared with the blast furnace dust from Chengdeng, the blast furnace dusts from Jiugang and Jinxin inhibited the diffusion of F-when used as reducing agents, leading to weaker effects of fluorite.
基金Supported by the Key Humanities and Social Sciences Project of the 13th FiveYear Plan in Hebei Province(1602079)
文摘As a national policy of benefiting the country and the people, " precision" poverty alleviation has an important strategic position.The core of " precision" poverty alleviation is education poverty alleviation. Based on the background of " precision" poverty alleviation,this study focuses on the analysis of problems of rural inclusive private kindergartens in the province,such as the shortage of rural pre-school resources,the uneven quality of teachers,and lack of financial investment. And in view of the existing problems,this paper puts forward some solutions to better promote the rural inclusive kindergarten development in the province.
基金supported by the National Natural Science Foundation of China (21975283)the Natural Science Foundation of Jiangsu Province (Youth Fund,Nos.BK20220601)+1 种基金State Key Laboratory of Chemistry and Utilization of Carbon-based Energy Resource (KFKT2021007)CAS Key Laboratory of Carbon Materials (KLCMKFJJ2010)。
文摘Rechargeable potassium-ion batteries(PIBs)have great potential in the application of electrochemical energy storage devices due to the low cost,the abundant resources and the low standard reduction potential of potassium.As electrode materials are the key factors to determine the electrochemical performance of devices,relevant research is being carried out to build high-performance PIBs.In recent years,significant progress has been made in the study of the design of inorganic electrode materials.Herein,we review the cathode materials(Prussian blue and its analogues,layered oxides and poly anionic compounds)and the anode materials(antimony-based,selenium-based and bismuth-based compounds).On the basis of previous work,the structural design principles for improving the performance of electrode materials are reasonably summarized.At the same time,the problems that need to be solved in the preparation of electrode materials and the direction of future research and improvement are pointed out.
基金This work is supported by the National Natural Science Foundation of China(Grant No.61575205).The authors would like to thank the team of Professor Fan Lüat the Eye Hospital of Wenzhou Medical University for providing clinical human ocular aberrations.
文摘Virtual Shack-Hartmann wavefront sensing(vSHWS)has some significant advantages and is promising for aberration measurement in the field of biomedical optical imaging.The illumination sources used in vSHWS are almost broadband,but are treated as monochromatic sources(only using center wavelength)in current data processing,which may cause errors.This work proposed a data processing method to take into account the multiple wavelengths of the broadband spectrum,named multiple-wavelength centroid-weighting method.Its feasibility was demonstrated through a series of simulations.A wavefront generated with a set of statistical human ocular aberrations was used as the target wavefront to evaluate the performance of the proposed and current methods.The results showed that their performance was very close when used for the symmetrical,but the wavefront error of the proposed method was much smaller than that of the current method when used for the asymmetrical spectrum,especially for the broader spectrum.These results were also validated by using 20 sets of clinical human ocular aberrations including normal and diseased eyes.The proposed method and the obtained conclusions have important implications for the application of vSHWS.
基金the Natural Science Foundation of China(No.51304012)the State Key Laboratory of High-Efficient Mining and Safety of Metal Mines for the financial support for this research
文摘A technique comprising coal-based direct reduction followed by magnetic separation was presented to recover iron and copper from copper slag flotation tailings.Optimal process parameters,such as reductant and additive ratios,reduction temperature,and reduction time,were experimentally determined and found to be as follows:a limestone ratio of 25%,a bitumite ratio of 30%,and reduction roasting at 1473 Kfor 90 min.Under these conditions,copper-bearing iron powders(CIP)with an iron content of 90.11% and copper content of 0.86%,indicating iron and copper recoveries of87.25% and 83.44%respectively,were effectively obtained.Scanning electron microscopy and energy dispersive spectroscopy of the CIP revealed that some tiny copper particles were embedded in metal iron and some copper formed alloy with iron,which was difficult to achieve the separation of these two metals.Thus,the copper went into magnetic products by magnetic separation.Adding copper into the steel can produce weathering steel.Therefore,the CIP can be used as an inexpensive raw material for weathering steel.
基金supported by the National Natural Science Foundation of China (31371191)
文摘In this study, treatment of C57 BL/6 J(wild type, WT) mice fed a high-fat diet(HFD) with retinoic acid(RA) decreased body weight and subcutaneous and visceral fat content, reversed the apparent hepatosteatosis, and reduced hepatic intracellular triglyceride and serum alanine transaminase(ALT) and aspartate aminotransferase(AST) concentrations. Moreover, RA treatment improved glucose tolerance and insulin sensitivity in WT mice fed a HFD. However, these RA-induced effects in WT mice fed a HFD were alleviated in liver specific Sirtuin 1(Sirt1) deficient(LKO) mice fed a HFD. Furthermore,RA also could not improve glucose tolerance and insulin sensitivity in LKO mice fed a HFD. The mechanism studies indicated that RA indeed increased the expression of hepatic Sirt1 and superoxide dismutase 2(Sod2), and inhibited the expression of sterol regulatory element binding protein 1 c(Srebp-1 c) in WT mice in vivo and in vitro. RA decreased mitochondrial reactive oxygen species(ROS) production in WT primary hepatocytes and increased mitochondrial DNA(mtDNA) copy number in WT mice liver. However, these RA-mediated molecular effects were also abolished in the liver and primary hepatocytes from LKO mice. In summary, RA protected against HFD-induced hepato steatosis by decreasing Srebp-1 c expression and improving antioxidant capacity through a Sirtl-mediated mechanism.
基金financially supported by the National Natural Science Foundation of China (Grant No.51474018)
文摘Embedding direct reduction followed by magnetic separation was conducted to fully recover iron and titanium separately from beach titanomagnetite (TTM). The influences of reduction conditions, such as molar ratio of C to Fe, reduction time, and reduction temperature, were studied. The results showed that the TTM concentrate was reduced to iron and iron-titanium oxides, depending on the reduction time, and the reduction sequence at 1 200℃ was suggested as follows : Fe2.75 Ti0.25O4→Fe2TiO4→FeTiO3→FeTi2O5. The reduction temperature played a considerable role in the reduction of TTM concentrates. Increasing temperature from 1 100 to 1 200℃ was beneficial to recovering titanium and iron, whereas the results deteriorated as temperature increased further. The results of X-ray diffraction and scanning electron microscopy analyses showed that low temperature (≤1100℃) was unfavorable for the gasification of reductant, resulting in insufficient reducing atmosphere in the reduction process. The molten phase was formed at high temperatures of 1250-1 300℃, which accelerated the migration rate of metallic particles and suppressed the diffusion of reduction gas, resulting in poor reduction. The optimum conditions for reducing TTM concentrate are as follows: molar ratio of C to Fe of 1.68, reduction time of 150 min, and reduction temperature of 1 200℃. Under these conditions, direct reduction iron powder, assaying 90.28 mass% TFe and 1.73 mass% TiO2 with iron recovery of 90.85%, and titanium concentrate, assaying 46.24 mass% TiO2 with TiO2 recovery of 91.15%, were obtained.
基金Item Sponsored by National Natural Science Foundation of China(51474018)
文摘The effect of sodium sulfate on direct reduction of beach titanomagnetite,followed by magnetic separation,to separate iron and titanium was investigated. Direct reduced iron( DRI) with a high Fe content,low TiO_2 content and low iron recovery was obtained after adding sodium sulfate. When the sodium sulfate dosage was increased from 0 to 10 mass%,the Fe content of the DRI increased from 90. 00 mass% to 93. 55 mass% and the TiO_2 content decreased from 1. 27 mass% to 0. 70 mass%. The reduction mechanism of sodium sulfate was investigated by X-ray diffraction( XRD) and scanning electron microscopy( SEM) with energy dispersive spectrometer( EDS). Results revealed that the metallic iron grains in the reduced ore with sodium sulfate were larger than those in the ore without sodium sulfate. Sodium sulfate promoted the migration of iron as well as the accumulation and growth of metallic iron grains by low-melting-point carnegieite and troilite formed in the redox system. Low-melting-point carnegieite decreased the melting point of the system and then promoted liquefaction. Troilite could decrease the surface tension and melting point of metallic iron grains.
基金the National Natural Science Foundation of China(Grant No.61764009,51762043,51974143)the National Key R&D Program of China(No.2018YFC1901801,No.2018YFC1901805)+2 种基金the Major Science and Technology Projects in Yunnan Province(No.2019ZE007)the Key Project of Yunnan Province Natural Science Fund(No.2018FA027)the Yunan Ten Thousand Talents Plan Young&Elite Talents Project,and the Program for Innovative Research Team in University of Ministry of Education of China(No.IRT_17R48).
文摘Graphene/silicon(Gr/Si)Schottky barrier solar cells(SBSCs)are attractive for harvesting solar energy and have been gaining grounds for its low-cost solution-processing.The interfacial barrier between graphene and silicon facilitates the reducing excessive carrier recombination while accelerating the separation processes of photo-generated carriers at the interface,which empowers the performance of Gr/Si SBSCs.However,the difficulty to control the interface thickness prevents its application.Here,we introduce the graphene oxide quantum dots(GOQDs)as a unique interfacial modulation species with tunable thickness by controlling the GOQDs particle size.The power conversion efficiency(PCE)of 13.67%for Gr/Si-based SBSC with outstanding stability in the air is obtained with the optimal barrier thickness(26 nm)and particle size(4.15 nm)of GOQDs.The GOQDs in Gr/Si-based SBSCs provide the extra band bending which further enhances the PCE for its photovoltaic applications.