The microstructure, phase composition and cold shut defect of thick titanium alloy electron beam welded joint were studied. The results showed that the microstructure of weld zone was composed of α′ phase; the heat ...The microstructure, phase composition and cold shut defect of thick titanium alloy electron beam welded joint were studied. The results showed that the microstructure of weld zone was composed of α′ phase; the heat affected zone was divided into fine-grained zone and coarse-grained zone, the microstructure of fine-grained zone was primary α phase ＋ β phase ＋ equiaxed α phase, and the microstructure of coarse-grained zone was primary α phase ＋ acicular α′ phase; the microstructure of base metal zone basically consisted of primary α phase, and a small amount of residual β phase sprinkled. The forming. reason of cold shut was analyzed, and the precaution of cold shut was proposed.展开更多
The volume defects in pure pyrite and quartz from a classical Cu-Pb-Zn-Fe sulfide deposit were investigated.The results indicate that a large number of volume defects exist in natural pyrite and quartz.The volume defe...The volume defects in pure pyrite and quartz from a classical Cu-Pb-Zn-Fe sulfide deposit were investigated.The results indicate that a large number of volume defects exist in natural pyrite and quartz.The volume defects assume a variety of shapes,including long strips,oval shapes and irregular shapes,with sizes ranging from a few microns to dozens of microns.These volume defects are rich in metallogenic elements as a result of the capture of metallogenic and mineralizing fluid during the defect-forming process.The volume defects are fractured during the grinding process,and their chemical components are released into the solution,as confirmed by the abundant presence of various metal and non-metal components in the cleaning water and EDS results.Under the experimental conditions of 10 g pyrite or quartz with grinding fineness of d90=37 μm,which was cleaned in 40 m L of pure deionised water under an inert atmosphere,the total average concentrations of Cu,Pb,Zn,Fe,Ca,Mg and Cl-in the aqueous solution are 32.09×10^-7,16.51×10^-7,19.45×10^-7,516.52×10^-7,129.50×10^-7,35.30×10^-7 and 433.80×10^-7 mol/L,respectively,for pyrite and 19.20×10^-7,8.88×10^-7,8.31×10^-7,82.71×10^-7,16.21×10^-7,4.28×10^-7 and 731.26×10^-7 mol/L,respectively,for quartz.These values are significantly greater than those from the experimental non-oxidative dissolution of the pyrite or quartz,respectively.Therefore,the metallogenic fluid in volume defects of mineral crystal is concluded to represent the dominant contribution to the solution chemistry of sulfide flotation pulp.The present investigation will help to deeply understand the flotation theory of sulfide minerals.展开更多
The past five years have witnessed the discovery of the endoplasmic reticulum calcium(Ca2+) sensor STIM1 and the plasma membrane Ca2+channel Orai1 as the bona fide molecular components of the store-operated Ca2+ entry...The past five years have witnessed the discovery of the endoplasmic reticulum calcium(Ca2+) sensor STIM1 and the plasma membrane Ca2+channel Orai1 as the bona fide molecular components of the store-operated Ca2+ entry(SOCE) and the Ca2+ release-activated Ca2+current(I CRAC) .It has been known for two decades that SOCE and ICRAC are required for lymphocyte activation as evidenced by severe immunodeficient phenotypes in patients lacking ICRAC.In recent years however,studies have uncovered expression of STIM1 and Orai1 proteins in various tissues and described additional roles for these proteins in physiological functions and pathophysiological conditions.Here,we will summarize novel findings pertaining to the role of STIM1 and Orai1 in the vascular system and discuss their potential use as targets in the therapy of vascular disease.展开更多
基金Project (2010CB731704) supported by the National Basic Research Program of China
文摘The microstructure, phase composition and cold shut defect of thick titanium alloy electron beam welded joint were studied. The results showed that the microstructure of weld zone was composed of α′ phase; the heat affected zone was divided into fine-grained zone and coarse-grained zone, the microstructure of fine-grained zone was primary α phase ＋ β phase ＋ equiaxed α phase, and the microstructure of coarse-grained zone was primary α phase ＋ acicular α′ phase; the microstructure of base metal zone basically consisted of primary α phase, and a small amount of residual β phase sprinkled. The forming. reason of cold shut was analyzed, and the precaution of cold shut was proposed.
基金Project(51464029)supported by the National Natural Science Foundation of ChinaProject(2014M562343)supported by the China Postdoctoral Science FoundationProject(KKSY201421110)supported the Scholar Development Project of Yunnan Province,China
文摘The volume defects in pure pyrite and quartz from a classical Cu-Pb-Zn-Fe sulfide deposit were investigated.The results indicate that a large number of volume defects exist in natural pyrite and quartz.The volume defects assume a variety of shapes,including long strips,oval shapes and irregular shapes,with sizes ranging from a few microns to dozens of microns.These volume defects are rich in metallogenic elements as a result of the capture of metallogenic and mineralizing fluid during the defect-forming process.The volume defects are fractured during the grinding process,and their chemical components are released into the solution,as confirmed by the abundant presence of various metal and non-metal components in the cleaning water and EDS results.Under the experimental conditions of 10 g pyrite or quartz with grinding fineness of d90=37 μm,which was cleaned in 40 m L of pure deionised water under an inert atmosphere,the total average concentrations of Cu,Pb,Zn,Fe,Ca,Mg and Cl-in the aqueous solution are 32.09×10^-7,16.51×10^-7,19.45×10^-7,516.52×10^-7,129.50×10^-7,35.30×10^-7 and 433.80×10^-7 mol/L,respectively,for pyrite and 19.20×10^-7,8.88×10^-7,8.31×10^-7,82.71×10^-7,16.21×10^-7,4.28×10^-7 and 731.26×10^-7 mol/L,respectively,for quartz.These values are significantly greater than those from the experimental non-oxidative dissolution of the pyrite or quartz,respectively.Therefore,the metallogenic fluid in volume defects of mineral crystal is concluded to represent the dominant contribution to the solution chemistry of sulfide flotation pulp.The present investigation will help to deeply understand the flotation theory of sulfide minerals.
基金supported by the National Institutes of Health(Grant No. 5R01HL097111)to Mohamed Trebak
文摘The past five years have witnessed the discovery of the endoplasmic reticulum calcium(Ca2+) sensor STIM1 and the plasma membrane Ca2+channel Orai1 as the bona fide molecular components of the store-operated Ca2+ entry(SOCE) and the Ca2+ release-activated Ca2+current(I CRAC) .It has been known for two decades that SOCE and ICRAC are required for lymphocyte activation as evidenced by severe immunodeficient phenotypes in patients lacking ICRAC.In recent years however,studies have uncovered expression of STIM1 and Orai1 proteins in various tissues and described additional roles for these proteins in physiological functions and pathophysiological conditions.Here,we will summarize novel findings pertaining to the role of STIM1 and Orai1 in the vascular system and discuss their potential use as targets in the therapy of vascular disease.
