A low MgO content in sinter is conducive to reduce the MgO content in blast furnace slag.This study investigated the effect of MgO content in sinter on the softening–melting behavior of the mixed burden based on flux...A low MgO content in sinter is conducive to reduce the MgO content in blast furnace slag.This study investigated the effect of MgO content in sinter on the softening–melting behavior of the mixed burden based on fluxed pellets.When the MgO content increased from 1.31 wt% to 1.55 wt%, the melting temperature of sinter increased to 1521℃.Such an increase was due to the formation of the high-meltingpoint slag phase.The reduction degradation index of sinter with 1.31 wt% MgO content was better than that of others.The initial softening temperature of the mixed burden increased from 1104 to 1126℃ as MgO content in sinter increased from 1.31 wt% to 1.55 wt%, and the melting temperature decreased from 1494 to 1460℃.The permeability index(S-value) of mixed burden decreased to 594.46 kPa·℃ under a high MgO content with 1.55 wt%, indicating that the permeability was improved.The slag phase composition of burden was mainly akermarite(Ca_(2)MgSiO_(7)) when the MgO content in sinter was 1.55 wt%.The melting point of akermarite is 1450℃, which is lower than other phases.展开更多
MgO participates in all stages of sintering,pelletizing,and blast furnace ironmaking,and synergistically optimizing the distribution of MgO in ferrous burden can effectively enhance the interaction within the ferrous ...MgO participates in all stages of sintering,pelletizing,and blast furnace ironmaking,and synergistically optimizing the distribution of MgO in ferrous burden can effectively enhance the interaction within the ferrous burdens and optimize the softening-melting properties of the mixed burden.Magnesium-containing pellets mixed with low-MgO sinter or mixed with high-MgO sinter in the blast furnace ferrous burden structure have opposite softening-melting performance laws.When the structure of the ferrous burden is magnesium-containing pellets mixed with low-MgO sinter,the magnesium-containing pellets can enhance the interaction of the ferrous burden in the process of softening-melting,which can optimize the composition of the slag phase and improve the slag liquidity.When the structure of the ferrous burden is magnesium-containing pellets mixed with high-MgO sinter,the magnesium-containing pellets weaken the interaction of the ferrous burden in the process of softening-melting,increase the content of the high melting point solid-phase particles in the slag,lead to an increase in the viscosity of the slag and difficult separation of the slag and iron,and decrease the permeability of the charge layer.Therefore,to ensure good permeability of the mixed burden,the following measures are suggested:optimizing the MgO distribution of the ferrous burden,reducing the MgO content of the sinter to 1.96 wt.%,increasing the MgO content of the pellets to 1.03-1.30 wt.%,controlling the MgO/Al_(2)O_(3) ratio of the mixed burden within 1.15-1.32,narrowing the position of the cohesive zone,and maintaining an S value(permeability index)of approximately 150 kPa℃.展开更多
Bismuth vanadate（BiVO4） has been investigated intensively and extensively due to its potential applications in the photocatalytic treatment of organiccontaining wastewater.In this study,Mo-BiVO4 samples were synthes...Bismuth vanadate（BiVO4） has been investigated intensively and extensively due to its potential applications in the photocatalytic treatment of organiccontaining wastewater.In this study,Mo-BiVO4 samples were synthesized by a facile sol-gel process.These samples were characterized by X-ray diffraction（XRD）,transmission electron microscopy（TEM）,and ultravioletvisible（UV-Vis） diffuse reflectance spectroscopy.It is found that the phase structure of Mo-BiVO4 photocatalyst is monoclinic scheelite.The photocatalytic activities of the obtained BiVO4 samples were investigated by means of the decolorization efficiency of methyl orange（MO）.The BiVO4 and Mo-BiVO4 photocatalysts show the response on the visible light.The doped BiVO4 photocatalysts show higher decolorization efficiency than that of bare BiVO4.展开更多
Double-authentication-preventing signature(DAPS) is a novel signature notion proposed at ESORICS2014. The double-authentication-preventing property means that any pair of signatures on two different messages with the ...Double-authentication-preventing signature(DAPS) is a novel signature notion proposed at ESORICS2014. The double-authentication-preventing property means that any pair of signatures on two different messages with the same subject will result in an immediate collapse of the signature system. A few potential applications of DAPS have been discussed by its inventors, such as providing a kind of self-enforcement to discourage certificate authority(CA) from misbehaving in public key infrastructure and offering CA some cryptographic arguments to resist legal coercion. In this study, we focus on some fundamental issues on DAPS. We propose a new definition,which is slightly weakened but still reasonable and strong enough to capture the DAPS concept. We develop the new notion of invertible chameleon hash functions with key exposure. Then we propose a generic DAPS scheme, which is provably secure if the underlying invertible chameleon hash function with key exposure is secure. We instantiate this general construction to obtain the DAPS schemes respectively based on the well-known assumptions of integer factorization, Rivest-Shamir-Adleman(RSA), and computational Diffie-Hellman(CDH). They are more efficient than previous DAPS schemes. Furthermore, unlike previous constructions, the trusted setup condition is not needed by our DAPS schemes based on RSA and CDH.展开更多
基金financially supported by the Fundamental Research Funds for the Central Universities, China (No.06500170)the Guangdong Basic and Applied Basic Research Foundation, China (No.2020A1515111008)。
文摘A low MgO content in sinter is conducive to reduce the MgO content in blast furnace slag.This study investigated the effect of MgO content in sinter on the softening–melting behavior of the mixed burden based on fluxed pellets.When the MgO content increased from 1.31 wt% to 1.55 wt%, the melting temperature of sinter increased to 1521℃.Such an increase was due to the formation of the high-meltingpoint slag phase.The reduction degradation index of sinter with 1.31 wt% MgO content was better than that of others.The initial softening temperature of the mixed burden increased from 1104 to 1126℃ as MgO content in sinter increased from 1.31 wt% to 1.55 wt%, and the melting temperature decreased from 1494 to 1460℃.The permeability index(S-value) of mixed burden decreased to 594.46 kPa·℃ under a high MgO content with 1.55 wt%, indicating that the permeability was improved.The slag phase composition of burden was mainly akermarite(Ca_(2)MgSiO_(7)) when the MgO content in sinter was 1.55 wt%.The melting point of akermarite is 1450℃, which is lower than other phases.
基金financial support of the National Natural Science Foundation of China (52174291)the National Natural Science Foundation of China Youth Fund (52204335)the Beijing New-Star of Science and Technology (Z211100002121115).
文摘MgO participates in all stages of sintering,pelletizing,and blast furnace ironmaking,and synergistically optimizing the distribution of MgO in ferrous burden can effectively enhance the interaction within the ferrous burdens and optimize the softening-melting properties of the mixed burden.Magnesium-containing pellets mixed with low-MgO sinter or mixed with high-MgO sinter in the blast furnace ferrous burden structure have opposite softening-melting performance laws.When the structure of the ferrous burden is magnesium-containing pellets mixed with low-MgO sinter,the magnesium-containing pellets can enhance the interaction of the ferrous burden in the process of softening-melting,which can optimize the composition of the slag phase and improve the slag liquidity.When the structure of the ferrous burden is magnesium-containing pellets mixed with high-MgO sinter,the magnesium-containing pellets weaken the interaction of the ferrous burden in the process of softening-melting,increase the content of the high melting point solid-phase particles in the slag,lead to an increase in the viscosity of the slag and difficult separation of the slag and iron,and decrease the permeability of the charge layer.Therefore,to ensure good permeability of the mixed burden,the following measures are suggested:optimizing the MgO distribution of the ferrous burden,reducing the MgO content of the sinter to 1.96 wt.%,increasing the MgO content of the pellets to 1.03-1.30 wt.%,controlling the MgO/Al_(2)O_(3) ratio of the mixed burden within 1.15-1.32,narrowing the position of the cohesive zone,and maintaining an S value(permeability index)of approximately 150 kPa℃.
基金financially supported by the Education Department Program of Heilongjiang Province(No.12541111)the Program for Innovative Research Team in University of Heilongjiang Province(No.2013TD008)
文摘Bismuth vanadate（BiVO4） has been investigated intensively and extensively due to its potential applications in the photocatalytic treatment of organiccontaining wastewater.In this study,Mo-BiVO4 samples were synthesized by a facile sol-gel process.These samples were characterized by X-ray diffraction（XRD）,transmission electron microscopy（TEM）,and ultravioletvisible（UV-Vis） diffuse reflectance spectroscopy.It is found that the phase structure of Mo-BiVO4 photocatalyst is monoclinic scheelite.The photocatalytic activities of the obtained BiVO4 samples were investigated by means of the decolorization efficiency of methyl orange（MO）.The BiVO4 and Mo-BiVO4 photocatalysts show the response on the visible light.The doped BiVO4 photocatalysts show higher decolorization efficiency than that of bare BiVO4.
基金Project supported by the National Natural Science Foundation of China(Nos.61202475,61133014,and 61472114)the Science and Technology Planning Key Project of Shandong Universities,China(No.J18KA326)the Science and Technology Planning Key Project of Guangdong Province,China(No.2016B010124014)
文摘Double-authentication-preventing signature(DAPS) is a novel signature notion proposed at ESORICS2014. The double-authentication-preventing property means that any pair of signatures on two different messages with the same subject will result in an immediate collapse of the signature system. A few potential applications of DAPS have been discussed by its inventors, such as providing a kind of self-enforcement to discourage certificate authority(CA) from misbehaving in public key infrastructure and offering CA some cryptographic arguments to resist legal coercion. In this study, we focus on some fundamental issues on DAPS. We propose a new definition,which is slightly weakened but still reasonable and strong enough to capture the DAPS concept. We develop the new notion of invertible chameleon hash functions with key exposure. Then we propose a generic DAPS scheme, which is provably secure if the underlying invertible chameleon hash function with key exposure is secure. We instantiate this general construction to obtain the DAPS schemes respectively based on the well-known assumptions of integer factorization, Rivest-Shamir-Adleman(RSA), and computational Diffie-Hellman(CDH). They are more efficient than previous DAPS schemes. Furthermore, unlike previous constructions, the trusted setup condition is not needed by our DAPS schemes based on RSA and CDH.
