The structure of aggregation state and isothermal crystallization behavior of Nylon-1010 have been studied by WAXD, DSE, Variance-Range Function and density measurement. The results show that crystallization of Nylon-...The structure of aggregation state and isothermal crystallization behavior of Nylon-1010 have been studied by WAXD, DSE, Variance-Range Function and density measurement. The results show that crystallization of Nylon-1010 has the most suitable annealing temperature, the crystals of the Nxlon-1010 are two-dimension heterogeneous nucleation. Both low treatment temperature and high crystallization te, temperature are disadvantageous for Nylon-1010 crystal growth.展开更多
Nephrolithiasis seems to be the result of crystal formation,aggregation and retention in the kidney during crystalluria.These processes have to occur within the short urinary transit time through the kidney being in t...Nephrolithiasis seems to be the result of crystal formation,aggregation and retention in the kidney during crystalluria.These processes have to occur within the short urinary transit time through the kidney being in the order of few minutes.Recently much work was done on rather qualitative aspects of nephrolithiasis like genetics,metabolism and morphology.In this review we try to provide some quantitative information on urinary supersaturation with respect to stone minerals,especially Ca oxalate(CaO x),on the formation and aggregation of Ca Ox crystals and on crystal retention in the kidney.The paper is centered on idiopathic Ca nephrolithiasis being the most frequent stone disease with only partially known pathogenesis.New aspects of the role of urinary macromolecules in stone formation and of the mechanism of crystal aggregation are provided.展开更多
The objective of this work is to study the reactive crystallization in an airlift-loop reactor (ALR) using the precipitation of Ni(OH)2 as a model reaction. The growth of Ni(OH)2 particles in an ALR and a stirre...The objective of this work is to study the reactive crystallization in an airlift-loop reactor (ALR) using the precipitation of Ni(OH)2 as a model reaction. The growth of Ni(OH)2 particles in an ALR and a stirred tank was quantified by scanning electronic microscope (SEM), X-ray diffraction (XRD), laser particle analyzer, tap densitometer and optical microscope, and the growth process of Ni(OH)2 particles is analyzed. It is found that the Ni(OH)2 particles prepared in an ALR have a better sphericity than those in a stirred tank and the growth of Ni(OH)2 particle tap density mainly depends on the size of crystallites: the bigger the size of crystallites, the bigger the tap density is. Based on these, the growth process of Ni(OH)2 particles in ALR is elaborated. Crystallites precipitated from solution aggregate to form large particles with much void. These constituting crystallites continue to grow up, that takes up the void inside particles and makes the tap densitv increase.展开更多
In the study on Ca-Mg silicate crystalline glazes, we found some disequilibrated crystallization phenomena, such as non-crystallographic small angle forking and spheroidal growth, parasitism and wedging-form of crysta...In the study on Ca-Mg silicate crystalline glazes, we found some disequilibrated crystallization phenomena, such as non-crystallographic small angle forking and spheroidal growth, parasitism and wedging-form of crystals, dendritic growth, secondary nucleation, etc. Those phenomena possibly resulted from two factors: (1) partial temperature gradient, which is caused by heat asymmetry in the electrical resistance furnace, when crystals crystalize from silicate melt; (2) constitutional supercooling near the surface of crystals. The disparity of disequilibrated crystallization phenomena in different main crystalline phases causes various morphological features of the crystal aggregates. At the same time, disequilibrated crystallization causes great stress retained in the crystals, which results in cracks in glazes when the temperature drops. According to the results, the authors analyzed those phenomena and displayed correlative figures and data.展开更多
An ionic iridium(Ⅲ) complex[Ir(F2dpyb)(bzdpp)2Cl][OTf]with 1,3-difluoro-4,6-di(2-pyridinyl) benzene(F2dpybH) terdentate ligand and benzyldiphenylphosphine(bzdpp)ligand was synthesized and characterized.Th...An ionic iridium(Ⅲ) complex[Ir(F2dpyb)(bzdpp)2Cl][OTf]with 1,3-difluoro-4,6-di(2-pyridinyl) benzene(F2dpybH) terdentate ligand and benzyldiphenylphosphine(bzdpp)ligand was synthesized and characterized.The structure of iridium complex was verified by single-crystal X-ray crystallography.It crystallizes in monoclinic,space group P21/n with a =14.3654(7),b = 23.0026(10),c = 15.7964(7) A°,β = 97.6029(11),V= 5173.9(4) A°3,Z = 4,F(000) =2552,Dc = 1.645 Mg/m^3,Mr = 1281.49 and μ = 0.071 mm^-1.The UV-vis absorption and phosphorescence of the complex were discussed.The complex was 'aggregation induced emission(AIE)' active.It exhibited no emission in CH2Cl2 solution but strong blue-green emission in solid state under ultraviolet light excitation.The complex emitted a strong phosphorescence centered at493 nm when doped in PMMA.Its lifetime is 0.755 μs and quantum yield is approximately 0.134.展开更多
文摘The structure of aggregation state and isothermal crystallization behavior of Nylon-1010 have been studied by WAXD, DSE, Variance-Range Function and density measurement. The results show that crystallization of Nylon-1010 has the most suitable annealing temperature, the crystals of the Nxlon-1010 are two-dimension heterogeneous nucleation. Both low treatment temperature and high crystallization te, temperature are disadvantageous for Nylon-1010 crystal growth.
文摘Nephrolithiasis seems to be the result of crystal formation,aggregation and retention in the kidney during crystalluria.These processes have to occur within the short urinary transit time through the kidney being in the order of few minutes.Recently much work was done on rather qualitative aspects of nephrolithiasis like genetics,metabolism and morphology.In this review we try to provide some quantitative information on urinary supersaturation with respect to stone minerals,especially Ca oxalate(CaO x),on the formation and aggregation of Ca Ox crystals and on crystal retention in the kidney.The paper is centered on idiopathic Ca nephrolithiasis being the most frequent stone disease with only partially known pathogenesis.New aspects of the role of urinary macromolecules in stone formation and of the mechanism of crystal aggregation are provided.
基金Supported by the National Key Research and Development Program(2016YFB0301701)the National Natural Science Foundation of China(21406236,91434126)+1 种基金the Major National Scientific Instrument Development Project(21427814)Jiangsu National Synergetic Innovation Center for Advanced Materials
文摘The objective of this work is to study the reactive crystallization in an airlift-loop reactor (ALR) using the precipitation of Ni(OH)2 as a model reaction. The growth of Ni(OH)2 particles in an ALR and a stirred tank was quantified by scanning electronic microscope (SEM), X-ray diffraction (XRD), laser particle analyzer, tap densitometer and optical microscope, and the growth process of Ni(OH)2 particles is analyzed. It is found that the Ni(OH)2 particles prepared in an ALR have a better sphericity than those in a stirred tank and the growth of Ni(OH)2 particle tap density mainly depends on the size of crystallites: the bigger the size of crystallites, the bigger the tap density is. Based on these, the growth process of Ni(OH)2 particles in ALR is elaborated. Crystallites precipitated from solution aggregate to form large particles with much void. These constituting crystallites continue to grow up, that takes up the void inside particles and makes the tap densitv increase.
基金Supported by the Natural Science Foundation of Fujian Province(No.D0 2 10 0 12 )
文摘In the study on Ca-Mg silicate crystalline glazes, we found some disequilibrated crystallization phenomena, such as non-crystallographic small angle forking and spheroidal growth, parasitism and wedging-form of crystals, dendritic growth, secondary nucleation, etc. Those phenomena possibly resulted from two factors: (1) partial temperature gradient, which is caused by heat asymmetry in the electrical resistance furnace, when crystals crystalize from silicate melt; (2) constitutional supercooling near the surface of crystals. The disparity of disequilibrated crystallization phenomena in different main crystalline phases causes various morphological features of the crystal aggregates. At the same time, disequilibrated crystallization causes great stress retained in the crystals, which results in cracks in glazes when the temperature drops. According to the results, the authors analyzed those phenomena and displayed correlative figures and data.
基金Supported by the National Natural Science Foundation of China(21572001)the Natural Science Foundation from Bureau of Education of Anhui Province(KJ2013A063)the Anhui Province Undergraduate Innovation and Entrepreneurship Training Program(201510360119)
文摘An ionic iridium(Ⅲ) complex[Ir(F2dpyb)(bzdpp)2Cl][OTf]with 1,3-difluoro-4,6-di(2-pyridinyl) benzene(F2dpybH) terdentate ligand and benzyldiphenylphosphine(bzdpp)ligand was synthesized and characterized.The structure of iridium complex was verified by single-crystal X-ray crystallography.It crystallizes in monoclinic,space group P21/n with a =14.3654(7),b = 23.0026(10),c = 15.7964(7) A°,β = 97.6029(11),V= 5173.9(4) A°3,Z = 4,F(000) =2552,Dc = 1.645 Mg/m^3,Mr = 1281.49 and μ = 0.071 mm^-1.The UV-vis absorption and phosphorescence of the complex were discussed.The complex was 'aggregation induced emission(AIE)' active.It exhibited no emission in CH2Cl2 solution but strong blue-green emission in solid state under ultraviolet light excitation.The complex emitted a strong phosphorescence centered at493 nm when doped in PMMA.Its lifetime is 0.755 μs and quantum yield is approximately 0.134.