Since the Cenozoic,a series of extensional south-north normal faults and gneiss-granite domes evolved in the southern Tibetan Plateau,the formation mechanism of which is of scientific interest and which has implicatio...Since the Cenozoic,a series of extensional south-north normal faults and gneiss-granite domes evolved in the southern Tibetan Plateau,the formation mechanism of which is of scientific interest and which has implications for the tectonic dynamics of the plateau.Typical of such features are the Xainza-Dinggye rift and the Mabja gneiss dome,which are located in the Xainza-Xietongmen-Dinggye region in the central Tibetan Plateau.In this study,Magnetotelluric measurements across this region are used to generate a high-resolution 3-D electrical resistivity model of the subsurface and to analyze the cause of the conductive zones.The large-scale conductive zones identified in the middle-lower crust may result from aqueous melt partial melting,whereas the smaller-scale conductive zones in the upper-middle crust may result from saline fluids,possibly with varying minor volumes of melts.Subsequently,based on the electrical resistivity model and combined with the spatiotemporal coupling of the geological,geochemical,and geophysical data,the state and migration features of crustal materials are discussed.The results show that the upwelling of mantle materials along subduction channels and slab-windows related to the tearing of the Indian lithospheric plate contributed to the partial melting of the middle-lower crust in the Lhasa terrane.Furthermore,partial melting of the upper-middle crust in the Tethys-Himalaya terrane resulted from southern extrusion of crustal materials in the Lhasa terrane.These two mechanisms can significantly reduce the effective viscosity.We speculate that the deformation of the brittle upper crust that is controlled by large-scale ductile layers characterized by weak rheology is the main dynamic mechanism of rift evolution.Meanwhile,the metamorphism and anatexis in the upper-middle crust of the Tethys-Himalaya terrane related to the southern extrusion of materials contributed to the evolution of the Mabja gneiss dome.During the middle Miocene,the southern extrusion of crustal materials may have been influenced by the cooling events beneath the Mabja gneiss dome,which can explain why the deep areas beneath the Mabja gneiss dome have middle-high resistivity.In addition,our study region is located in the Mediterranean-Himalayan seismic belt,and mainly includes shallow-focus earthquakes and intermediate-depth earthquakes.In the north,shallow-focus earthquakes are mainly controlled by the accumulation of stress in the brittle layer of the overlying crust related to the ductile layer of the middle and lower crust.In the south,shallow-focus earthquakes(e.g.,Dingri MS6.8 earthquake)mainly occur in the rigid,resistive block,which is surrounded by conductive zones,possibly because fluid migration may be hindered by these resistive blocks.The intermediate-depth earthquakes are mainly controlled by the response in the subsurface area,which is related to the detachment of the Indian lithospheric mantle from the Indian crust.展开更多
Polyacrylamide hydrogel(PAAG)was once considered a safe,reliable,and compatible injected filler and was widely used in breast augmentation,rhinoplasty,and other cosmetic surgeries.However,numerous complications,such a...Polyacrylamide hydrogel(PAAG)was once considered a safe,reliable,and compatible injected filler and was widely used in breast augmentation,rhinoplasty,and other cosmetic surgeries.However,numerous complications,such as implant migration,have been observed after PAAG injections.Herein,we report a rare case of distant implant migration after PAAG injection for breast augmentation in which the material became displaced along the abdominal wall to the perineum and pelvic extraperitoneal space.After a well-prepared preoperative evaluation involving magnetic resonance imaging(MRI)and computed tomography(CT)examinations and threedimensional hologram,debridement surgery was performed to remove the injected material.After the operation,the patient was followed up for two years and was not scheduled for a second operation.Postoperative complications of breast augmentation after PAAG injection,especially gel migration,still affect thousands of patients.Once material migration occurs,surgical removal becomes difficult.Early diagnosis and treatment are recommended.展开更多
An overview of diagnostic tools e test limiters and collector probes e used over the years for material migration studies in the TEXTOR tokamak is presented.Probe transfer systems are shown and their technical capabil...An overview of diagnostic tools e test limiters and collector probes e used over the years for material migration studies in the TEXTOR tokamak is presented.Probe transfer systems are shown and their technical capabilities are described.This is accompanied by a brief pre-sentation of selected results and conclusions from the research on material erosion e deposition processes including tests of candidate materials(e.g.W,Mo,carbon-based composites)for plasma-facing components in controlled fusion devices.The use of tracer techniques and methods for analysis of materials retrieved from the tokamak are summarized.The impact of research on the reactor wall technology is addressed.展开更多
Using mobile gravity data from the central area of Sichuan and Yunnan Provinces, the relationship between gravity variation and earthquakes was studied based on the Ludian Ms6.5 earthquake that occurred on August 3rd,...Using mobile gravity data from the central area of Sichuan and Yunnan Provinces, the relationship between gravity variation and earthquakes was studied based on the Ludian Ms6.5 earthquake that occurred on August 3rd, 2014, and the Kangding Ms6.3 earthquake that occurred on November 22 nd, 2014; the mechanism of gravity variation was also explored. The results are as follows：（1） Prior to both earthquakes, gravity variation exhibited similar characteristics as those observed before both the Tangshan and Wenchuan earthquakes, in which typical precursor anomalies were positive gravity variation near the epicenter and the occurrence of a high-gravity-gradient zone across the epicenter prior to the earthquake.（2） A relatively accurate prediction of the occurrence locations of the two earthquakes was made by the Gravity Network Center of China（GNCC） based on these precursor anomalies. In the gravity study report on the 2014 earthquake trends submitted at the end of 2013, the Daofu-Shimian section at the junction of the Xianshuihe and Longmenshan fault zones was noted as an earthquake-risk region with a predicted magnitude of 6.5, which covered the epicenter of the Kangding Ms6.3 earthquake. In another report on earthquake trends in southwestern China submitted in mid-2014, the Lianfeng, Zhaotong fault zone was also classified as an earthquake-risk region with a magnitude of 6.0, and the central area of this region basically overlapped with the epicenter of the Ludian Ms6.5 earthquake.（3） The gravity variation characteristics are reasonably consistent with crustal movements, and deep material migration is likely the primary cause of gravity variation.展开更多
The boundary between subtropical zone and temperate zone is not only important in physical geography, but also attractive in agricultural production. Seven soil profiles studied in this pape...The boundary between subtropical zone and temperate zone is not only important in physical geography, but also attractive in agricultural production. Seven soil profiles studied in this paper are placed along the southern slope of Funiu Mountain at different heights above sea level. Many compositions and properties of these soils have been determined in laboratory. In this paper, the laws of migration and accumulation of soil materials on the southern slope of Funiu Mountain are discussed first, then the division of the boundary between subtropical zone and temperate zone in this area according to soil geochemistry is discussed with qualitative methods and mathematical classification method in which twelve selected indexes such as K m , Saf, Ba, β, Feo/Fet, Mno/Mnt and so on are used. The result indicates that the boundary between subtropical zone and temperate zone on the southern slope of Funiu Mountain is about 950 m above sea level.展开更多
This review places emphasis on ancient lunar nonmare igneous samples alkali-suite and Mg-suite.The material on mineralogy and petrology of the Mg-suite presented here draws from“Lunar samples”by Papike et al.and“Or...This review places emphasis on ancient lunar nonmare igneous samples alkali-suite and Mg-suite.The material on mineralogy and petrology of the Mg-suite presented here draws from“Lunar samples”by Papike et al.and“Origin of the lunar highlands Mg-suite:An integrated petrology,geochemistry,chronology,and remote sensing perspective”by Shearer et al.Readers can refer to these comprehensive studies for more information.The in-depth studies on Chang'e-5(CE-5)lunar basaltic samples put new constraints on the thermal state of lunar interior,although the discussions on their formation mechanism heavily rely on the lunar magma ocean(LMO)models.Yet,chemical composition and structure of the lunar mantle are modified by migration of lunar materials during or after LMO fractionation.Alkali-suite rocks and Mg-suites are two important ancient lunar sample suites that represent early lunar magmatic activities.Studies on these samples are crucial to inverse modeling the pattern and scale of material migration inside the Moon during the“post-LMO”period.However,some Mg-suite samples and granitic samples are found outside the Procellarum KREEP(K,REE[rare earth element],and P)Terrane,bringing difficulties to explain their chemical characteristics and formation mechanisms.More work is needed to constrain the primitive melt formed deeply inside the Moon based on the updated LMO models,and to quantify the scale and effect of lunar mantle overturn.In addition,analysis on more lunar samples and lunar exploration missions with emphasis on ancient samples will also help to constrain their formation mechanisms,to refine the LMO differentiation models,and to depict the constitution of the lunar interior.展开更多
Ordered mesoporous Cu-Mg-A1 composite oxides were synthesized via the one-pot evaporation-in- duced self-assembly strategy. Using this method, copper was first homogeneously incorporated into the ordered mesoporous sp...Ordered mesoporous Cu-Mg-A1 composite oxides were synthesized via the one-pot evaporation-in- duced self-assembly strategy. Using this method, copper was first homogeneously incorporated into the ordered mesoporous spinel matrix. After H2 reduction treatment, according to X-ray diffraction （XRD） and transmission electron microscopy （TEM） results, copper existed as metallic nanoparticles with the size of 6-10 nm that well decorated the parent mesoporous skeleton. The metallic nanoparticles were then re-oxidized to copper oxide when exposed to air or during CO oxidation reaction at low temperatures. Thus, copper migrated from bulk spinel phase to the surface after the reduction-oxidation treat- ment. Moreover, the copper on the surface was re-incor- porated into the bulk spinel phase by further thermal treatment at much higher temperature in the presence of air. The correlation between the state of copper in the mesoporous composite oxides and the catalytic perfor- mance toward CO oxidation was studied. It was found that copper existed as oxide nanoparticles on the surface of mesoporous Mg-Al skeleton is much more active than that existed as lattice Cu ions in spinel phase.展开更多
基金supported by the High-performance Computing Platform of China University of Geosciences,Beijingsupported by the National Natural Science Foundation of China(Grant No.42304087)+1 种基金the National Key R&D Program of China(Grant No.2022YFF0800901)the Fundamental Research Funds for the Central Universities(Grant No.29-2023-202)。
文摘Since the Cenozoic,a series of extensional south-north normal faults and gneiss-granite domes evolved in the southern Tibetan Plateau,the formation mechanism of which is of scientific interest and which has implications for the tectonic dynamics of the plateau.Typical of such features are the Xainza-Dinggye rift and the Mabja gneiss dome,which are located in the Xainza-Xietongmen-Dinggye region in the central Tibetan Plateau.In this study,Magnetotelluric measurements across this region are used to generate a high-resolution 3-D electrical resistivity model of the subsurface and to analyze the cause of the conductive zones.The large-scale conductive zones identified in the middle-lower crust may result from aqueous melt partial melting,whereas the smaller-scale conductive zones in the upper-middle crust may result from saline fluids,possibly with varying minor volumes of melts.Subsequently,based on the electrical resistivity model and combined with the spatiotemporal coupling of the geological,geochemical,and geophysical data,the state and migration features of crustal materials are discussed.The results show that the upwelling of mantle materials along subduction channels and slab-windows related to the tearing of the Indian lithospheric plate contributed to the partial melting of the middle-lower crust in the Lhasa terrane.Furthermore,partial melting of the upper-middle crust in the Tethys-Himalaya terrane resulted from southern extrusion of crustal materials in the Lhasa terrane.These two mechanisms can significantly reduce the effective viscosity.We speculate that the deformation of the brittle upper crust that is controlled by large-scale ductile layers characterized by weak rheology is the main dynamic mechanism of rift evolution.Meanwhile,the metamorphism and anatexis in the upper-middle crust of the Tethys-Himalaya terrane related to the southern extrusion of materials contributed to the evolution of the Mabja gneiss dome.During the middle Miocene,the southern extrusion of crustal materials may have been influenced by the cooling events beneath the Mabja gneiss dome,which can explain why the deep areas beneath the Mabja gneiss dome have middle-high resistivity.In addition,our study region is located in the Mediterranean-Himalayan seismic belt,and mainly includes shallow-focus earthquakes and intermediate-depth earthquakes.In the north,shallow-focus earthquakes are mainly controlled by the accumulation of stress in the brittle layer of the overlying crust related to the ductile layer of the middle and lower crust.In the south,shallow-focus earthquakes(e.g.,Dingri MS6.8 earthquake)mainly occur in the rigid,resistive block,which is surrounded by conductive zones,possibly because fluid migration may be hindered by these resistive blocks.The intermediate-depth earthquakes are mainly controlled by the response in the subsurface area,which is related to the detachment of the Indian lithospheric mantle from the Indian crust.
基金This work was supported by the Chongqing Higher Education Teaching Reform Project(grant no.193373).
文摘Polyacrylamide hydrogel(PAAG)was once considered a safe,reliable,and compatible injected filler and was widely used in breast augmentation,rhinoplasty,and other cosmetic surgeries.However,numerous complications,such as implant migration,have been observed after PAAG injections.Herein,we report a rare case of distant implant migration after PAAG injection for breast augmentation in which the material became displaced along the abdominal wall to the perineum and pelvic extraperitoneal space.After a well-prepared preoperative evaluation involving magnetic resonance imaging(MRI)and computed tomography(CT)examinations and threedimensional hologram,debridement surgery was performed to remove the injected material.After the operation,the patient was followed up for two years and was not scheduled for a second operation.Postoperative complications of breast augmentation after PAAG injection,especially gel migration,still affect thousands of patients.Once material migration occurs,surgical removal becomes difficult.Early diagnosis and treatment are recommended.
文摘An overview of diagnostic tools e test limiters and collector probes e used over the years for material migration studies in the TEXTOR tokamak is presented.Probe transfer systems are shown and their technical capabilities are described.This is accompanied by a brief pre-sentation of selected results and conclusions from the research on material erosion e deposition processes including tests of candidate materials(e.g.W,Mo,carbon-based composites)for plasma-facing components in controlled fusion devices.The use of tracer techniques and methods for analysis of materials retrieved from the tokamak are summarized.The impact of research on the reactor wall technology is addressed.
基金jointly supported by the Director Foundation of Institute of Seismology,China Earthquake Administration(IS201326121)the special earthquake research grant offered by the China Earthquake Administration(201208009,201308009)the National Natural Science Foundation of China(41304059)
文摘Using mobile gravity data from the central area of Sichuan and Yunnan Provinces, the relationship between gravity variation and earthquakes was studied based on the Ludian Ms6.5 earthquake that occurred on August 3rd, 2014, and the Kangding Ms6.3 earthquake that occurred on November 22 nd, 2014; the mechanism of gravity variation was also explored. The results are as follows：（1） Prior to both earthquakes, gravity variation exhibited similar characteristics as those observed before both the Tangshan and Wenchuan earthquakes, in which typical precursor anomalies were positive gravity variation near the epicenter and the occurrence of a high-gravity-gradient zone across the epicenter prior to the earthquake.（2） A relatively accurate prediction of the occurrence locations of the two earthquakes was made by the Gravity Network Center of China（GNCC） based on these precursor anomalies. In the gravity study report on the 2014 earthquake trends submitted at the end of 2013, the Daofu-Shimian section at the junction of the Xianshuihe and Longmenshan fault zones was noted as an earthquake-risk region with a predicted magnitude of 6.5, which covered the epicenter of the Kangding Ms6.3 earthquake. In another report on earthquake trends in southwestern China submitted in mid-2014, the Lianfeng, Zhaotong fault zone was also classified as an earthquake-risk region with a magnitude of 6.0, and the central area of this region basically overlapped with the epicenter of the Ludian Ms6.5 earthquake.（3） The gravity variation characteristics are reasonably consistent with crustal movements, and deep material migration is likely the primary cause of gravity variation.
基金National Natural Science Foundation of China No.49070028
文摘The boundary between subtropical zone and temperate zone is not only important in physical geography, but also attractive in agricultural production. Seven soil profiles studied in this paper are placed along the southern slope of Funiu Mountain at different heights above sea level. Many compositions and properties of these soils have been determined in laboratory. In this paper, the laws of migration and accumulation of soil materials on the southern slope of Funiu Mountain are discussed first, then the division of the boundary between subtropical zone and temperate zone in this area according to soil geochemistry is discussed with qualitative methods and mathematical classification method in which twelve selected indexes such as K m , Saf, Ba, β, Feo/Fet, Mno/Mnt and so on are used. The result indicates that the boundary between subtropical zone and temperate zone on the southern slope of Funiu Mountain is about 950 m above sea level.
基金the National Natural Science Foundation of China[grant numbers 41773052,41973058,42373041,and L2224032]the Strategic Priority Research Program of Chinese Academy of Sciences[grant number XDB 41000000]+1 种基金the key research program of frontier sciences of Chinese Academy of Sciences[grant number ZDBS-SSW-JSC007-10Project on Frontier and Interdisciplinary Research Assessment,Academic Divisions of the Chinese Academy of Sciences(XK2022DXC004)].
文摘This review places emphasis on ancient lunar nonmare igneous samples alkali-suite and Mg-suite.The material on mineralogy and petrology of the Mg-suite presented here draws from“Lunar samples”by Papike et al.and“Origin of the lunar highlands Mg-suite:An integrated petrology,geochemistry,chronology,and remote sensing perspective”by Shearer et al.Readers can refer to these comprehensive studies for more information.The in-depth studies on Chang'e-5(CE-5)lunar basaltic samples put new constraints on the thermal state of lunar interior,although the discussions on their formation mechanism heavily rely on the lunar magma ocean(LMO)models.Yet,chemical composition and structure of the lunar mantle are modified by migration of lunar materials during or after LMO fractionation.Alkali-suite rocks and Mg-suites are two important ancient lunar sample suites that represent early lunar magmatic activities.Studies on these samples are crucial to inverse modeling the pattern and scale of material migration inside the Moon during the“post-LMO”period.However,some Mg-suite samples and granitic samples are found outside the Procellarum KREEP(K,REE[rare earth element],and P)Terrane,bringing difficulties to explain their chemical characteristics and formation mechanisms.More work is needed to constrain the primitive melt formed deeply inside the Moon based on the updated LMO models,and to quantify the scale and effect of lunar mantle overturn.In addition,analysis on more lunar samples and lunar exploration missions with emphasis on ancient samples will also help to constrain their formation mechanisms,to refine the LMO differentiation models,and to depict the constitution of the lunar interior.
基金This work was supported by the Recruitment Program of Global Youth Experts of China, the National Natural Science Foundation of China （21403267, 21450110410）, and Shandong Postdoctoral Innovation Program （201303065）.
文摘Ordered mesoporous Cu-Mg-A1 composite oxides were synthesized via the one-pot evaporation-in- duced self-assembly strategy. Using this method, copper was first homogeneously incorporated into the ordered mesoporous spinel matrix. After H2 reduction treatment, according to X-ray diffraction （XRD） and transmission electron microscopy （TEM） results, copper existed as metallic nanoparticles with the size of 6-10 nm that well decorated the parent mesoporous skeleton. The metallic nanoparticles were then re-oxidized to copper oxide when exposed to air or during CO oxidation reaction at low temperatures. Thus, copper migrated from bulk spinel phase to the surface after the reduction-oxidation treat- ment. Moreover, the copper on the surface was re-incor- porated into the bulk spinel phase by further thermal treatment at much higher temperature in the presence of air. The correlation between the state of copper in the mesoporous composite oxides and the catalytic perfor- mance toward CO oxidation was studied. It was found that copper existed as oxide nanoparticles on the surface of mesoporous Mg-Al skeleton is much more active than that existed as lattice Cu ions in spinel phase.
