The Wugong Mts. region may have experienced three stages of metamorphism in Early Paleo-zoic, which may be closely related to the generations of regional deformation. The first stage ismedium-pressure metamorphism, th...The Wugong Mts. region may have experienced three stages of metamorphism in Early Paleo-zoic, which may be closely related to the generations of regional deformation. The first stage ismedium-pressure metamorphism, the second medium- and high-pressure one with stress on high-pressure metamorphism, and the third low-pressure and high-temperature metamorphism. Theregion, as a whole, is a Caledonian medium-high pressure metamorphic belt.展开更多
Silicate glass-ceramics were prepared by adding 40 wt%granite wastes.The effects of CaO/MgO(C/M)molar ratio on microstructure and mechanical properties of glass-ceramics were investigated.With C/M ratio increasing,the...Silicate glass-ceramics were prepared by adding 40 wt%granite wastes.The effects of CaO/MgO(C/M)molar ratio on microstructure and mechanical properties of glass-ceramics were investigated.With C/M ratio increasing,the crystallization behavior changed from bulk crystallization to surface crystallization with heat treatment at 800℃.However,bulk crystallization occurred in all samples when crystallized at both 850 and 900℃.The content of forsterite and tainiolite initially increased and then decreased,while diopside and kalsilite increased when heated at 850℃.For 900℃,the increase of C/M ratio promoted the precipitation of diopside rather than forsterite and tainiolite,and interlocked plate crystals abundantly appeared with C/M ratio≥0.14.The values of Vickers hardness for samples crystallized at 850 and 900℃increased initially followed by a decrease,while the values of fracture toughness showed the opposite trend.The glass-ceramic with C/M ratio 0.065 heated at 900℃showed relatively high Vickers hardness((5.7±0.14)GPa)and excellent fracture toughness((3.55±0.14)MPa·m^(1/2)).展开更多
The surface of MoSi2-SiB6/phenolic resin matrix composites was modified by mica,and the thermal oxidation behavior of the composites and the mechanical properties of the pyrolysis products were studied.The results sho...The surface of MoSi2-SiB6/phenolic resin matrix composites was modified by mica,and the thermal oxidation behavior of the composites and the mechanical properties of the pyrolysis products were studied.The results showed that the mica improved the thermal properties of the composites,the thermal expansion coefficient decreased,and the liquid phase formation caused the composites to shrink and increase the density.The flexural strength of mica surface modified composites not only increased to 78.64MPa after thermal treatment at 800-1200℃,but reached 83.02 MPa after high temperature treatment at1400℃.The improvement of the mechanical properties of the residual product benefits from the formation of high temperature ceramic phases such as Mo_(2)C and MoB,and the improvement of the shear strength of the composites by the mica.The shear strength of MBm5-2 at room temperature reached 33.08 MPa,indicating that the improvement of the interlayer properties of the composites further improved its mechanical properties.展开更多
The micaceous weathered granitic soil(WGS)is frequently encountered in civil engineering worldwide,unfortunately little information is available regarding how mica affects the physico-mechanical behaviors of WGS.This ...The micaceous weathered granitic soil(WGS)is frequently encountered in civil engineering worldwide,unfortunately little information is available regarding how mica affects the physico-mechanical behaviors of WGS.This study prepares reconstituted WGS with different mica contents by removing natural mica in theWGS,and then mixes it with commercial mica powders.The geotechnical behavior as well as the microstructures of the mixtures are characterized.The addition of mica enables the physical indices of WGS to be specific combinations of coarser gradation and high permeability but high Atterberg limits.However,high mica content in WGS was found to be associated with undesirable mechanical properties,including increased compressibility,disintegration,and swelling potential,as well as poor compactability and low effective frictional angle.Microstructural analysis indicates that the influence of mica on the responses of mixtures originates from the intrinsic nature of mica as well as the particle packing being formed withinWGS.Mica exists in the mixture as stacks of plates that form a spongy structure with high compressibility and swelling potential.Pores among the plates give the soil high water retention and high Atterberg limits.Large pores are also generated by soil particles with bridging packing,which enhances the permeability and water-soil interactions upon immersion.This study provides a microlevel understanding of how mica dominates the behavior of WGS and provides new insights into the effective stabilization and improvement of micaceous soils.展开更多
Heavy metals from mica waste not only deteriorate the soil quality but also results in the uptake of metals in the crop.The present investigation was conducted to evaluate the effects of different fractions of metals ...Heavy metals from mica waste not only deteriorate the soil quality but also results in the uptake of metals in the crop.The present investigation was conducted to evaluate the effects of different fractions of metals on the uptake in rice,soil microbial and biochemical properties in mica waste-contaminated soils of Jharkhand,India.From each active mine,soil samples were randomly collected at distances of<50 m(zone 1),50–100 m(zone 2),and>100 m(zone 3).Sequential metal extraction was used to determine the fractions of different metals(nickel(Ni),cadmium(Cd),chromium(Cr)and lead(Pb))including water-soluble(Ws)and exchangeable metals(Ex),carbonate-bound metals(CBD),Fe/Mn oxide(OXD)bound metals,organically bound metals(ORG),and residues(RS).The Ni,Cr,Cd and Pb in rice grain were 0.83±0.41,0.41±0.19,0.21±0.14 and 0.17±0.08 mg/kg respectively.From the variable importance plot of the random forest(RF)algorithm,the Ws fraction of Ni,Cr and Cd and Ex fraction of Pb was the most important predictor for rice grain metal content.Further,the partial dependence plots(PDP)give us an insight into the role of the two most important metal fractions on rice grain metal content.The microbial and enzyme activity was significantly and negatively correlated with Ws and Ex metal fractions,indicating that water-soluble and exchangeable fractions exert a strong inhibitory effect on the soil microbiological parameters and enzyme activities.展开更多
Enterprise mergers and acquisitions(M&A)are vital strategies for companies worldwide to expand markets,enhance competitiveness,and achieve strategic goals.The Chinese government’s strong support for the new energ...Enterprise mergers and acquisitions(M&A)are vital strategies for companies worldwide to expand markets,enhance competitiveness,and achieve strategic goals.The Chinese government’s strong support for the new energy industry has created a favorable policy environment for the development of the lithium battery sector.Against this backdrop,Tianqi Lithium Corp’s acquisition of Sociedad Química y Minera(SQM)in Chile has garnered widespread attention.This paper takes Tianqi Lithium Corp’s acquisition of SQM as the research subject,conducting a detailed analysis of the motives behind the M&A.Subsequently,financial indicators are employed to conduct a performance analysis from a financial perspective,examining the impact of the M&A.Finally,based on the findings of the case analysis,relevant suggestions are proposed to offer a reference for the development of enterprise mergers and acquisitions.展开更多
目的观察乳腺肿瘤细胞膜MHCⅠ链相关分子A(MHC class I chain-related gene A,MICA)及血清中可溶性MICA表达,探讨MICA在NK细胞杀伤乳腺癌中的作用。方法流式细胞术检测膜型MICA(mMICA)及NK细胞表面NKG2D表达,观察膜型MICA、可溶性MICA(s...目的观察乳腺肿瘤细胞膜MHCⅠ链相关分子A(MHC class I chain-related gene A,MICA)及血清中可溶性MICA表达,探讨MICA在NK细胞杀伤乳腺癌中的作用。方法流式细胞术检测膜型MICA(mMICA)及NK细胞表面NKG2D表达,观察膜型MICA、可溶性MICA(sMICA)对NKG2D表达的影响;免疫组织化学检测膜型MICA及可溶性MICA的表达及分布;抗体封闭法观察膜型MICA与NKG2D相互作用。结果乳腺细胞膜型MICA在正常组织不表达,在良性肿瘤表达量为(38.5±7.5)%,恶性肿瘤表达量为(53.2±5.6)%。可溶性MICA含量在健康成年人为阴性,在乳腺良性肿瘤患者血清中含量(76.8±22.3)pg/mL,在恶性肿瘤患者中含量(205.36±71.27)pg/mL。经NKG2D或MICA抗体封闭后,NK细胞的杀瘤活性显著减弱。含可溶性MICA的血清可明显下调NKG2D的表达。结论大部分乳腺肿瘤细胞膜都有MICA的表达,可作为乳腺肿瘤相关性抗原。膜型MICA与NKG2D的相互识别在介导NK细胞抗乳腺癌中起重要作用,而可溶性MICA通过下调NKG2D表达介导肿瘤免疫逃逸。展开更多
文摘The Wugong Mts. region may have experienced three stages of metamorphism in Early Paleo-zoic, which may be closely related to the generations of regional deformation. The first stage ismedium-pressure metamorphism, the second medium- and high-pressure one with stress on high-pressure metamorphism, and the third low-pressure and high-temperature metamorphism. Theregion, as a whole, is a Caledonian medium-high pressure metamorphic belt.
基金National Natural Science Foundation of China(Nos.52172019,51804131)Shandong Provincial Youth Innovation Team Development Plan of Colleges and Universities(No.2022KJ100)。
文摘Silicate glass-ceramics were prepared by adding 40 wt%granite wastes.The effects of CaO/MgO(C/M)molar ratio on microstructure and mechanical properties of glass-ceramics were investigated.With C/M ratio increasing,the crystallization behavior changed from bulk crystallization to surface crystallization with heat treatment at 800℃.However,bulk crystallization occurred in all samples when crystallized at both 850 and 900℃.The content of forsterite and tainiolite initially increased and then decreased,while diopside and kalsilite increased when heated at 850℃.For 900℃,the increase of C/M ratio promoted the precipitation of diopside rather than forsterite and tainiolite,and interlocked plate crystals abundantly appeared with C/M ratio≥0.14.The values of Vickers hardness for samples crystallized at 850 and 900℃increased initially followed by a decrease,while the values of fracture toughness showed the opposite trend.The glass-ceramic with C/M ratio 0.065 heated at 900℃showed relatively high Vickers hardness((5.7±0.14)GPa)and excellent fracture toughness((3.55±0.14)MPa·m^(1/2)).
基金Funded by the National Natural Science Foundation of China(Nos.52171045,52162013,and 51932006)。
文摘The surface of MoSi2-SiB6/phenolic resin matrix composites was modified by mica,and the thermal oxidation behavior of the composites and the mechanical properties of the pyrolysis products were studied.The results showed that the mica improved the thermal properties of the composites,the thermal expansion coefficient decreased,and the liquid phase formation caused the composites to shrink and increase the density.The flexural strength of mica surface modified composites not only increased to 78.64MPa after thermal treatment at 800-1200℃,but reached 83.02 MPa after high temperature treatment at1400℃.The improvement of the mechanical properties of the residual product benefits from the formation of high temperature ceramic phases such as Mo_(2)C and MoB,and the improvement of the shear strength of the composites by the mica.The shear strength of MBm5-2 at room temperature reached 33.08 MPa,indicating that the improvement of the interlayer properties of the composites further improved its mechanical properties.
基金The financial supports of the National Natural Science Foundation of China(Grant No.42177148)the opening fund of State Key Laboratory of Geohazard Prevention and Geo-environment Protection(Grant No.SKLGP 2023K011)Postdoctoral Research Project of Guangzhou(Grant No.20220402)are gratefully thanked.
文摘The micaceous weathered granitic soil(WGS)is frequently encountered in civil engineering worldwide,unfortunately little information is available regarding how mica affects the physico-mechanical behaviors of WGS.This study prepares reconstituted WGS with different mica contents by removing natural mica in theWGS,and then mixes it with commercial mica powders.The geotechnical behavior as well as the microstructures of the mixtures are characterized.The addition of mica enables the physical indices of WGS to be specific combinations of coarser gradation and high permeability but high Atterberg limits.However,high mica content in WGS was found to be associated with undesirable mechanical properties,including increased compressibility,disintegration,and swelling potential,as well as poor compactability and low effective frictional angle.Microstructural analysis indicates that the influence of mica on the responses of mixtures originates from the intrinsic nature of mica as well as the particle packing being formed withinWGS.Mica exists in the mixture as stacks of plates that form a spongy structure with high compressibility and swelling potential.Pores among the plates give the soil high water retention and high Atterberg limits.Large pores are also generated by soil particles with bridging packing,which enhances the permeability and water-soil interactions upon immersion.This study provides a microlevel understanding of how mica dominates the behavior of WGS and provides new insights into the effective stabilization and improvement of micaceous soils.
文摘Heavy metals from mica waste not only deteriorate the soil quality but also results in the uptake of metals in the crop.The present investigation was conducted to evaluate the effects of different fractions of metals on the uptake in rice,soil microbial and biochemical properties in mica waste-contaminated soils of Jharkhand,India.From each active mine,soil samples were randomly collected at distances of<50 m(zone 1),50–100 m(zone 2),and>100 m(zone 3).Sequential metal extraction was used to determine the fractions of different metals(nickel(Ni),cadmium(Cd),chromium(Cr)and lead(Pb))including water-soluble(Ws)and exchangeable metals(Ex),carbonate-bound metals(CBD),Fe/Mn oxide(OXD)bound metals,organically bound metals(ORG),and residues(RS).The Ni,Cr,Cd and Pb in rice grain were 0.83±0.41,0.41±0.19,0.21±0.14 and 0.17±0.08 mg/kg respectively.From the variable importance plot of the random forest(RF)algorithm,the Ws fraction of Ni,Cr and Cd and Ex fraction of Pb was the most important predictor for rice grain metal content.Further,the partial dependence plots(PDP)give us an insight into the role of the two most important metal fractions on rice grain metal content.The microbial and enzyme activity was significantly and negatively correlated with Ws and Ex metal fractions,indicating that water-soluble and exchangeable fractions exert a strong inhibitory effect on the soil microbiological parameters and enzyme activities.
文摘Enterprise mergers and acquisitions(M&A)are vital strategies for companies worldwide to expand markets,enhance competitiveness,and achieve strategic goals.The Chinese government’s strong support for the new energy industry has created a favorable policy environment for the development of the lithium battery sector.Against this backdrop,Tianqi Lithium Corp’s acquisition of Sociedad Química y Minera(SQM)in Chile has garnered widespread attention.This paper takes Tianqi Lithium Corp’s acquisition of SQM as the research subject,conducting a detailed analysis of the motives behind the M&A.Subsequently,financial indicators are employed to conduct a performance analysis from a financial perspective,examining the impact of the M&A.Finally,based on the findings of the case analysis,relevant suggestions are proposed to offer a reference for the development of enterprise mergers and acquisitions.
文摘目的观察乳腺肿瘤细胞膜MHCⅠ链相关分子A(MHC class I chain-related gene A,MICA)及血清中可溶性MICA表达,探讨MICA在NK细胞杀伤乳腺癌中的作用。方法流式细胞术检测膜型MICA(mMICA)及NK细胞表面NKG2D表达,观察膜型MICA、可溶性MICA(sMICA)对NKG2D表达的影响;免疫组织化学检测膜型MICA及可溶性MICA的表达及分布;抗体封闭法观察膜型MICA与NKG2D相互作用。结果乳腺细胞膜型MICA在正常组织不表达,在良性肿瘤表达量为(38.5±7.5)%,恶性肿瘤表达量为(53.2±5.6)%。可溶性MICA含量在健康成年人为阴性,在乳腺良性肿瘤患者血清中含量(76.8±22.3)pg/mL,在恶性肿瘤患者中含量(205.36±71.27)pg/mL。经NKG2D或MICA抗体封闭后,NK细胞的杀瘤活性显著减弱。含可溶性MICA的血清可明显下调NKG2D的表达。结论大部分乳腺肿瘤细胞膜都有MICA的表达,可作为乳腺肿瘤相关性抗原。膜型MICA与NKG2D的相互识别在介导NK细胞抗乳腺癌中起重要作用,而可溶性MICA通过下调NKG2D表达介导肿瘤免疫逃逸。
