Surface modification of sericite by wet method was conducted with the addition of 1.0 % （w/w） silane. The resulting wetting contact angle and activity ratio of sericite were 130° and 98% respectively. Good pre-...Surface modification of sericite by wet method was conducted with the addition of 1.0 % （w/w） silane. The resulting wetting contact angle and activity ratio of sericite were 130° and 98% respectively. Good pre-evaluation indexes of oil value （40.8%） and dispersivity （14.0 mL） were obtained. When 30 % of sericite was filled into acrylonitrile butadiene styrene（ABS） plastic, the bending strength and tensile strength of the composite material were reduced by 7% and 14.3% in comparison to those of pure ABS plastic, while the rigidity was increased by 3 times, and the impact strength and breaking elongation were reduced significantly. The mechanism of surface modification was investigated and the configuration of silane coupling agent on the surface of sericite was given. Infrared （IR） spectroscopic analysis indicates that the adsorption of silane on the surface of sericite belongs to chemical adsorption.展开更多
A rarely encountered sericite was investigated using X-ray diffraction,differential thermal analysis,and scanning electron microscopy.XRD analysis shows that the pattern of the sericite in the sample is similar to tha...A rarely encountered sericite was investigated using X-ray diffraction,differential thermal analysis,and scanning electron microscopy.XRD analysis shows that the pattern of the sericite in the sample is similar to that of illite.DTA (TG) analyses show that only a weak heat absorption reaction takes place at 566℃,which is contributed to the polymorphic transformation of quartz,and no change in mass was detected in the range from ambient temperature to 800℃.These reveal that no water escapes from the crystal structure of the clay mineral during heating and therefore indicated that the clay mineral is obviously sericite in species instead of illite.SEM observations show that the sericite particles are significantly small in size and growth steps and irregular structures develop on the crystal surfaces as well as the colored mineral inclusions,which might suggest some loss of optical properties of the sample and thus lead to the variance,with earthy luster of the aggregate,from typical sericite in optical characters.展开更多
Objective Hyperspectral remote sensing has attracted much attention in remote sensing research during recent years. It can elaborately identiry spectral characteristics of different objects by acquiring continuous sp...Objective Hyperspectral remote sensing has attracted much attention in remote sensing research during recent years. It can elaborately identiry spectral characteristics of different objects by acquiring continuous spectral curves of ground objects, and can thus provide more information for geological research （Zhao Yingjun et al., 2015）. With the deepening hyperspectral remote sensing research, scholars have focused from the classification of alteration minerals to the identification of subclass minerals in order to explore their significance fbr ore prospecting. This work utilized hyperspectral remote sensing technology in the Xitan region of Gansu Province to identify limonite and two types of sericite subclass minerals, and conducted field verification and geochemical survey. In addition, we analyzed the geological environment of subclass sericite minerals （Van Ruitenbeek et al., 2006） to provide evidence for gold ore prospecting.展开更多
TiO2-coated sericite powders were prepared by the chemical deposition method starting from lamellar sericite and TiCl4 in the presence of La3+. After calcination at 900 ℃ for 1 h, the resultant TiO2 nanoparticles on ...TiO2-coated sericite powders were prepared by the chemical deposition method starting from lamellar sericite and TiCl4 in the presence of La3+. After calcination at 900 ℃ for 1 h, the resultant TiO2 nanoparticles on the sericite surfaces exist in anatase phase. The light scattering indexes of the TiO2-coated lamellar sericite powders are dozens of times higher than those of the naked lamellar sericite powders, varying with different contents of La3+. The presence of La3+ in the deposition solution is beneficial to the formation of the small-sized anatase TiO2 nanoparticles. The presence of La3+ also favors the formation of the dense and uniform island-like TiO2 coating layers in a large range of the mass ratio of TiO2 to sericite from 5% to 20%. XPS analysis shows that when La3+ is absent in the reaction solution, TiO2 coating layers anchor on the sericite surface via Ti—O—Si and Ti—O—Al bonds. The presence of La3+ causes the formation of Si—O—La and Al—O—La bonds on the sericite surface and Ti—O—La bond on the surface of TiO2 coating layers.展开更多
The mechanical properties of ozonized high density polyethylene(HDPE)blended with sericite-tridymite-cristobalite(STC)were studied in this paper.The experimental results show that some oxygen containing polar groups a...The mechanical properties of ozonized high density polyethylene(HDPE)blended with sericite-tridymite-cristobalite(STC)were studied in this paper.The experimental results show that some oxygen containing polar groups areintroduced on the molecular chain of HDPE through ozonization,the compatibility between HDPE and STC is thusimproved,the mechanical properties of the blend are markedly enhanced.Compared with untreated HDPE/STC(60/40)blend,the yield strength and notched impact strength of ozonized HDPE/STC(60/40)blend are increased from 27.0 MPa to29.5 MPa and from 2.8 kJ/m^2 to 13.3 kJ/m^2,respectively,the notched impact strength is close to that of HDPE(13.6 kJ/m^2),the yield strength is in excess of 3.9 MPa of that of HDPE.The yield strength and notched impact strength will be furtherincreased to 30.7 MPa and 32.4 kJ/m^2 in case the ozonized HDPE is blended with STC pretreated with silane coupling agent.展开更多
The effect of γ-ray irradiation on the mechanical properties of high densitypolyethylene(HDPE) filled with sericite-tridymite-cristobalite(STC) was studied. The ex-perimental results show that γ-ray irradiation can ...The effect of γ-ray irradiation on the mechanical properties of high densitypolyethylene(HDPE) filled with sericite-tridymite-cristobalite(STC) was studied. The ex-perimental results show that γ-ray irradiation can improve the affinity between HDPE andSTC, and the dispersion of STC in HDPE matrix. Compared with HDPE/STC (80/20)blend, the yield stress and impact strength of irradiated HDPE (10kGy)/STC (80/20) blendare increased from 22.8 MPa and 70J/m to 28.5 MPa and 144J/m. The yield stress andimpact strength of HDPE/irradiated HDPE/STC (48/32/20) are 27.8MPa and 210J/m,respectively.展开更多
The Qinling orogen in central China contains several black shale-hosted gold deposits,but the age of their formation and a possible relation between gold mineralization and regional tectonism remain undetermined.Here ...The Qinling orogen in central China contains several black shale-hosted gold deposits,but the age of their formation and a possible relation between gold mineralization and regional tectonism remain undetermined.Here we present results of in situ monazite U-Th-Pb dating and sericite Rb-Sr dating of the Xiajiadian black shale-hosted gold deposit to provide tight constraints on the time of gold deposition and information on the tectonic setting under which the deposit formed.The Xiajiadian gold deposit is mainly hosted in black shales of the Lower Cambrian Shuigoukou formation,with minor ores contained in sandy conglomerate of the Lower Devonian Xichahe formation.Gold ores in the black shales have been intensively oxidized and consist mainly of hematite,goethite,gypsum,quartz,calcite,native gold,and unrecognized iron oxides.However,gold ores in the sandy conglomerate are free of oxidation and thus provide an opportunity to date the formation of the Xiajiadian gold deposit.The ores consist of pyrite,marcasite,sericite,and quartz,which are associated with a variety of accessory minerals,including monazite,apatite,and titanite.Gold is mainly present as structure-bound ions or nanoparticles in pyrite and marcasite,but minor native gold grains also occur as inclusions in pyrite.Monazite is well developed in the ores,and has close textural association with Au-bearing pyrite and marcasite.Most monazite grains have zoned textures consisting of a core area(Mnz1)and an overgrowth zone(Mnz2).Mnz1 contains 4.8–13 wt.%ThO_(2)and shows large variations in HREE and prominent negative Eu anomalies in the chondrite-normalized REE patterns.It yields common lead-corrected^(208)Pb/^(232)Th dates ranging from 910±10 to416±4 Ma(2σ).These dates are interpreted in terms of a detrital origin for monazite in the core area.Mnz2 has much lower ThO_(2)contents of 0.8–1.7 wt.%and shows weak negative Eu anomalies in the chondrite-normalized REE patterns.It yields common lead-corrected^(208)Pb/^(232)Th dates of 229–209 Ma(2σ)with a weighted mean of 217.6±3.0 Ma(2σ),which is considered as the time of Mnz2 crystallization.Sericite in gold ores and associated alteration zones has close relations to Au-bearing pyrite and marcasite,and yields a well-defined Rb-Sr isochron age of 222.2±3.3 Ma(2σ).The sericite Rb-Sr age is indistinguishable within analytical errors from the weighted mean Th-Pb age of Mnz2.The age data presented here indicate that the Xiajiadian gold deposit formed at ca.220 Ma in the Late Triassic(Norian).We therefore suggest that gold mineralization at Xiajiadian occurred during the transitional stage from oceanic subduction to continental collision that led to the formation of the Qinling orogen.During this stage,metamorphic devolatization of the underlying Early Paleozoic to Proterozoic carbonaceous sequences likely supplied ore fluids from which the Xiajiadian gold deposit formed.展开更多
基金the National Eleventh-Five-Year Project of China(No.2006BAB12B01)
文摘Surface modification of sericite by wet method was conducted with the addition of 1.0 % （w/w） silane. The resulting wetting contact angle and activity ratio of sericite were 130° and 98% respectively. Good pre-evaluation indexes of oil value （40.8%） and dispersivity （14.0 mL） were obtained. When 30 % of sericite was filled into acrylonitrile butadiene styrene（ABS） plastic, the bending strength and tensile strength of the composite material were reduced by 7% and 14.3% in comparison to those of pure ABS plastic, while the rigidity was increased by 3 times, and the impact strength and breaking elongation were reduced significantly. The mechanism of surface modification was investigated and the configuration of silane coupling agent on the surface of sericite was given. Infrared （IR） spectroscopic analysis indicates that the adsorption of silane on the surface of sericite belongs to chemical adsorption.
文摘A rarely encountered sericite was investigated using X-ray diffraction,differential thermal analysis,and scanning electron microscopy.XRD analysis shows that the pattern of the sericite in the sample is similar to that of illite.DTA (TG) analyses show that only a weak heat absorption reaction takes place at 566℃,which is contributed to the polymorphic transformation of quartz,and no change in mass was detected in the range from ambient temperature to 800℃.These reveal that no water escapes from the crystal structure of the clay mineral during heating and therefore indicated that the clay mineral is obviously sericite in species instead of illite.SEM observations show that the sericite particles are significantly small in size and growth steps and irregular structures develop on the crystal surfaces as well as the colored mineral inclusions,which might suggest some loss of optical properties of the sample and thus lead to the variance,with earthy luster of the aggregate,from typical sericite in optical characters.
基金financially supported by the National Natural Science Foundation of China(No.51204011)the Science and Technology Project for the Guidance Teacher of Beijing Excellent Doctoral Dissertation(No.20121000803)
基金financially supported by the research project of China National Uranium Limited Company(grant No.201498)the China Geological Survey Project(grant No.12120113072900)
文摘Objective Hyperspectral remote sensing has attracted much attention in remote sensing research during recent years. It can elaborately identiry spectral characteristics of different objects by acquiring continuous spectral curves of ground objects, and can thus provide more information for geological research （Zhao Yingjun et al., 2015）. With the deepening hyperspectral remote sensing research, scholars have focused from the classification of alteration minerals to the identification of subclass minerals in order to explore their significance fbr ore prospecting. This work utilized hyperspectral remote sensing technology in the Xitan region of Gansu Province to identify limonite and two types of sericite subclass minerals, and conducted field verification and geochemical survey. In addition, we analyzed the geological environment of subclass sericite minerals （Van Ruitenbeek et al., 2006） to provide evidence for gold ore prospecting.
基金Project(2003406) supported by the Chinese Education DepartmentProject(BG2006025) supported by Bureau of Science and Technology of Jiangsu Province, China
文摘TiO2-coated sericite powders were prepared by the chemical deposition method starting from lamellar sericite and TiCl4 in the presence of La3+. After calcination at 900 ℃ for 1 h, the resultant TiO2 nanoparticles on the sericite surfaces exist in anatase phase. The light scattering indexes of the TiO2-coated lamellar sericite powders are dozens of times higher than those of the naked lamellar sericite powders, varying with different contents of La3+. The presence of La3+ in the deposition solution is beneficial to the formation of the small-sized anatase TiO2 nanoparticles. The presence of La3+ also favors the formation of the dense and uniform island-like TiO2 coating layers in a large range of the mass ratio of TiO2 to sericite from 5% to 20%. XPS analysis shows that when La3+ is absent in the reaction solution, TiO2 coating layers anchor on the sericite surface via Ti—O—Si and Ti—O—Al bonds. The presence of La3+ causes the formation of Si—O—La and Al—O—La bonds on the sericite surface and Ti—O—La bond on the surface of TiO2 coating layers.
基金This project was supported by the Special Funds for Major State Basic Research Projects of China(No.G1999064809).
文摘The mechanical properties of ozonized high density polyethylene(HDPE)blended with sericite-tridymite-cristobalite(STC)were studied in this paper.The experimental results show that some oxygen containing polar groups areintroduced on the molecular chain of HDPE through ozonization,the compatibility between HDPE and STC is thusimproved,the mechanical properties of the blend are markedly enhanced.Compared with untreated HDPE/STC(60/40)blend,the yield strength and notched impact strength of ozonized HDPE/STC(60/40)blend are increased from 27.0 MPa to29.5 MPa and from 2.8 kJ/m^2 to 13.3 kJ/m^2,respectively,the notched impact strength is close to that of HDPE(13.6 kJ/m^2),the yield strength is in excess of 3.9 MPa of that of HDPE.The yield strength and notched impact strength will be furtherincreased to 30.7 MPa and 32.4 kJ/m^2 in case the ozonized HDPE is blended with STC pretreated with silane coupling agent.
基金Project supported by the National Natural Science Foundation of China and Ford-China R & D Fund.
文摘The effect of γ-ray irradiation on the mechanical properties of high densitypolyethylene(HDPE) filled with sericite-tridymite-cristobalite(STC) was studied. The ex-perimental results show that γ-ray irradiation can improve the affinity between HDPE andSTC, and the dispersion of STC in HDPE matrix. Compared with HDPE/STC (80/20)blend, the yield stress and impact strength of irradiated HDPE (10kGy)/STC (80/20) blendare increased from 22.8 MPa and 70J/m to 28.5 MPa and 144J/m. The yield stress andimpact strength of HDPE/irradiated HDPE/STC (48/32/20) are 27.8MPa and 210J/m,respectively.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.42130814 and 42321001)。
文摘The Qinling orogen in central China contains several black shale-hosted gold deposits,but the age of their formation and a possible relation between gold mineralization and regional tectonism remain undetermined.Here we present results of in situ monazite U-Th-Pb dating and sericite Rb-Sr dating of the Xiajiadian black shale-hosted gold deposit to provide tight constraints on the time of gold deposition and information on the tectonic setting under which the deposit formed.The Xiajiadian gold deposit is mainly hosted in black shales of the Lower Cambrian Shuigoukou formation,with minor ores contained in sandy conglomerate of the Lower Devonian Xichahe formation.Gold ores in the black shales have been intensively oxidized and consist mainly of hematite,goethite,gypsum,quartz,calcite,native gold,and unrecognized iron oxides.However,gold ores in the sandy conglomerate are free of oxidation and thus provide an opportunity to date the formation of the Xiajiadian gold deposit.The ores consist of pyrite,marcasite,sericite,and quartz,which are associated with a variety of accessory minerals,including monazite,apatite,and titanite.Gold is mainly present as structure-bound ions or nanoparticles in pyrite and marcasite,but minor native gold grains also occur as inclusions in pyrite.Monazite is well developed in the ores,and has close textural association with Au-bearing pyrite and marcasite.Most monazite grains have zoned textures consisting of a core area(Mnz1)and an overgrowth zone(Mnz2).Mnz1 contains 4.8–13 wt.%ThO_(2)and shows large variations in HREE and prominent negative Eu anomalies in the chondrite-normalized REE patterns.It yields common lead-corrected^(208)Pb/^(232)Th dates ranging from 910±10 to416±4 Ma(2σ).These dates are interpreted in terms of a detrital origin for monazite in the core area.Mnz2 has much lower ThO_(2)contents of 0.8–1.7 wt.%and shows weak negative Eu anomalies in the chondrite-normalized REE patterns.It yields common lead-corrected^(208)Pb/^(232)Th dates of 229–209 Ma(2σ)with a weighted mean of 217.6±3.0 Ma(2σ),which is considered as the time of Mnz2 crystallization.Sericite in gold ores and associated alteration zones has close relations to Au-bearing pyrite and marcasite,and yields a well-defined Rb-Sr isochron age of 222.2±3.3 Ma(2σ).The sericite Rb-Sr age is indistinguishable within analytical errors from the weighted mean Th-Pb age of Mnz2.The age data presented here indicate that the Xiajiadian gold deposit formed at ca.220 Ma in the Late Triassic(Norian).We therefore suggest that gold mineralization at Xiajiadian occurred during the transitional stage from oceanic subduction to continental collision that led to the formation of the Qinling orogen.During this stage,metamorphic devolatization of the underlying Early Paleozoic to Proterozoic carbonaceous sequences likely supplied ore fluids from which the Xiajiadian gold deposit formed.
