Ti-Fe-x TiC(x=0, 3, 6, 9, wt.%) composites were fabricated through low temperature ball milling of Ti, Fe and TiC powders, followed by spark plasma sintering. The results show that β-Ti, β-Ti-Fe, η-Ti4 Fe2 O0.4 and...Ti-Fe-x TiC(x=0, 3, 6, 9, wt.%) composites were fabricated through low temperature ball milling of Ti, Fe and TiC powders, followed by spark plasma sintering. The results show that β-Ti, β-Ti-Fe, η-Ti4 Fe2 O0.4 and TiC particles can be found in the composites. The microstructure can be obviously refined with increasing the content of TiC particles. The coefficient of friction(COF) decreases and the hardness increases with increasing the content of TiC particles. The adhesive wear is the dominant wear mechanism of all the Ti-Fe-x TiC composites. The Ti-Fe-6 TiC composite shows the best wear resistance, owing to the small size and high content of TiC particle as well as relatively fine microstructure. The wear rate of the Ti-Fe-6 TiC composite is as low as 1.869× 10-5 mm3/(N·m) and the COF is only 0.64. Therefore, TiC particle reinforced Ti-Fe based composites may be utilized as potential wear resistant materials.展开更多
Amorphous materials are one of the important candidates for improving heterogeneous photocata-lysts because of their unique electronic structures and abundant catalytic sites originating from dis-order atomic arrangem...Amorphous materials are one of the important candidates for improving heterogeneous photocata-lysts because of their unique electronic structures and abundant catalytic sites originating from dis-order atomic arrangements.However,there is still much room for the development of new crys-talline/amorphous heterogeneous composites for photocatalytic application.Hence efficient synthetic strategies for preparing new crystalline/amorphous heterojunctions are highly desired.Herein,we have realized the deep optimization of photocatalytic activity by fabricating crystalline/amorphous Cu_(2)O/Ti-Fe layer double hydroxide(LDH)heterojunctions.Thanks to the typical Z-scheme mechanism originating from the crystalline/amorphous interfaces,the photocharge separation and catalytic active sites obviously enhance compared to single Cu_(2)O and LDH counterparts.As expected,the photocatalytic removal of tetra-cycline(TC)of the as-prepared Cu_(2)O/Ti-Fe LDH was over 5.2 and 2.2 times those of the pristine Cu_(2)O nanospheres and Ti-Fe LDH nanosheets.This work illustrates the origin of crystalline Cu_(2)O nanospheres encapsulated in amorphous Ti-Fe layer double hydroxide nanosheets for enhanced photocatalytic activity driven by visible light,and provide a general Cu_(2)O-templated solution-phase synthetic method for the synthesis of novel double-metal layer double hydroxide amorphous nanostructures.展开更多
There are two types of temporally and spatially associated intrusions within the Emeishan large igneous province （LIP）; namely, small ultramafic subvolcanic sills that host magmatic Cu-Ni-Platinum Group Element （PG...There are two types of temporally and spatially associated intrusions within the Emeishan large igneous province （LIP）; namely, small ultramafic subvolcanic sills that host magmatic Cu-Ni-Platinum Group Element （PGE）-bearing sulfide deposits and large mafic layered intrusions that host giant Ti-V magnetite deposits in the Panxi region. However, except for their coeval ages, the genetic relations between the ore-bearing intrusions and extrusive rocks are poorly understood. Phase equilibria analysis （Q-PI-OI-Opx-Cpx system） has been carried out to elucidate whether ore-bearing Panzhihua, Xinjie and Limahe intrusions are co-magmatic with the picrites and flood basalts （including high-Ti, low-Ti and alkali basalts）, respectively. In this system, the parental magma can be classified as silica-undersaturated olivine basalt and silica-saturated tholeiite. The equivalents of the parental magma of the Xinjie and Limahe peridotites and picrites and low-Ti basalts are silica-undersaturated, whereas the Limahe gabbro-diorites and high-Ti basalts are silica-saturated. In contrast, the Panzhihua intrusion appears to be alkali character. Phase equilibria relations clearly show that the magmas that formed the Panzhihua intrusion and high-Ti basalts cannot be co-magmatic as there is no way to derive one liquid from another by fractional crystallization. On the other hand, the Panzhihua intrusion appears to be related to Permian alkali intrusions in the region, but does not appear to be related to the alkali basalts recognized in the Longzhoushan lava stratigraphy. Comparably, the Limahe intrusion appears to be a genetic relation to the picrites, whereas the Xinjie intrusion may be genetically related to be low-Ti basalts. Additionally, the gabbro-diorites and peridotites of the Limahe intrusion are not co-magmatic, and the former appears to be derived liquid from high-Ti basalts.展开更多
基金financial support from the National Key Fundamental Research and Development Project of China (2014CB644002)。
文摘Ti-Fe-x TiC(x=0, 3, 6, 9, wt.%) composites were fabricated through low temperature ball milling of Ti, Fe and TiC powders, followed by spark plasma sintering. The results show that β-Ti, β-Ti-Fe, η-Ti4 Fe2 O0.4 and TiC particles can be found in the composites. The microstructure can be obviously refined with increasing the content of TiC particles. The coefficient of friction(COF) decreases and the hardness increases with increasing the content of TiC particles. The adhesive wear is the dominant wear mechanism of all the Ti-Fe-x TiC composites. The Ti-Fe-6 TiC composite shows the best wear resistance, owing to the small size and high content of TiC particle as well as relatively fine microstructure. The wear rate of the Ti-Fe-6 TiC composite is as low as 1.869× 10-5 mm3/(N·m) and the COF is only 0.64. Therefore, TiC particle reinforced Ti-Fe based composites may be utilized as potential wear resistant materials.
文摘Amorphous materials are one of the important candidates for improving heterogeneous photocata-lysts because of their unique electronic structures and abundant catalytic sites originating from dis-order atomic arrangements.However,there is still much room for the development of new crys-talline/amorphous heterogeneous composites for photocatalytic application.Hence efficient synthetic strategies for preparing new crystalline/amorphous heterojunctions are highly desired.Herein,we have realized the deep optimization of photocatalytic activity by fabricating crystalline/amorphous Cu_(2)O/Ti-Fe layer double hydroxide(LDH)heterojunctions.Thanks to the typical Z-scheme mechanism originating from the crystalline/amorphous interfaces,the photocharge separation and catalytic active sites obviously enhance compared to single Cu_(2)O and LDH counterparts.As expected,the photocatalytic removal of tetra-cycline(TC)of the as-prepared Cu_(2)O/Ti-Fe LDH was over 5.2 and 2.2 times those of the pristine Cu_(2)O nanospheres and Ti-Fe LDH nanosheets.This work illustrates the origin of crystalline Cu_(2)O nanospheres encapsulated in amorphous Ti-Fe layer double hydroxide nanosheets for enhanced photocatalytic activity driven by visible light,and provide a general Cu_(2)O-templated solution-phase synthetic method for the synthesis of novel double-metal layer double hydroxide amorphous nanostructures.
基金supported by the National Basic Research Program of China(2009CB421002)National Natural Science Foundation of China(Grant No.40473008,40273020,40572036)+1 种基金Program for New Century Excellent Talents in University(Grant No.NCET-04-0728)Project(B07011)and PCSIRT.
文摘There are two types of temporally and spatially associated intrusions within the Emeishan large igneous province （LIP）; namely, small ultramafic subvolcanic sills that host magmatic Cu-Ni-Platinum Group Element （PGE）-bearing sulfide deposits and large mafic layered intrusions that host giant Ti-V magnetite deposits in the Panxi region. However, except for their coeval ages, the genetic relations between the ore-bearing intrusions and extrusive rocks are poorly understood. Phase equilibria analysis （Q-PI-OI-Opx-Cpx system） has been carried out to elucidate whether ore-bearing Panzhihua, Xinjie and Limahe intrusions are co-magmatic with the picrites and flood basalts （including high-Ti, low-Ti and alkali basalts）, respectively. In this system, the parental magma can be classified as silica-undersaturated olivine basalt and silica-saturated tholeiite. The equivalents of the parental magma of the Xinjie and Limahe peridotites and picrites and low-Ti basalts are silica-undersaturated, whereas the Limahe gabbro-diorites and high-Ti basalts are silica-saturated. In contrast, the Panzhihua intrusion appears to be alkali character. Phase equilibria relations clearly show that the magmas that formed the Panzhihua intrusion and high-Ti basalts cannot be co-magmatic as there is no way to derive one liquid from another by fractional crystallization. On the other hand, the Panzhihua intrusion appears to be related to Permian alkali intrusions in the region, but does not appear to be related to the alkali basalts recognized in the Longzhoushan lava stratigraphy. Comparably, the Limahe intrusion appears to be a genetic relation to the picrites, whereas the Xinjie intrusion may be genetically related to be low-Ti basalts. Additionally, the gabbro-diorites and peridotites of the Limahe intrusion are not co-magmatic, and the former appears to be derived liquid from high-Ti basalts.
