A shear induced ordered structure in PS/montmorillonite nanocomposite was observed for the first time by wide angle X ray diffraction technique. A transmission electron microscopy result showed that the randomly place...A shear induced ordered structure in PS/montmorillonite nanocomposite was observed for the first time by wide angle X ray diffraction technique. A transmission electron microscopy result showed that the randomly placed primary particles of montmorillonite were oriented parallel to the pellet surface, and the interior of the primary particles became more ordered as well. These results suggested that the orientation of the primary particles as well as the interior ordered structure induced by the shear flow were perhaps the origin of the ordered structure in the PS/montmorillonite nanocomposite.展开更多
目的:探讨枸橼酸咖啡因联合肺表面活性物质(PS)对新生儿呼吸窘迫综合征(NRDS)患儿肺功能及血清氨基末端脑钠肽前体(amino-terminal pro-brain natriuretic peptide,NT-ProBNP)、白介素-6(inter-leukin-6,IL-6)水平的关联。方法:选2019年...目的:探讨枸橼酸咖啡因联合肺表面活性物质(PS)对新生儿呼吸窘迫综合征(NRDS)患儿肺功能及血清氨基末端脑钠肽前体(amino-terminal pro-brain natriuretic peptide,NT-ProBNP)、白介素-6(inter-leukin-6,IL-6)水平的关联。方法:选2019年7月至2020年7月在我院接受治疗的NRDS患儿80例按随机数字表余数法分为观察组与对照组,每组各40例。对照组予以PS治疗,观察组在对照组基础上加用枸橼酸咖啡因。比较两组临床疗效、肺功能指标、血清NT-proBNP和IL-6水平以及并发症发生率。结果:治疗后,观察组总有效率显著高于对照组(P<0.05)。治疗后观察组达峰时间比(ratio of time to peak tidal expiratory flow and total expiratory time,TPEF/TE)、达峰容积比(ratio of expiratory volume at peak tidal expiratory flow and total expiratory volume,VPEF/VE)及每千克体重潮气量(Tidal volume/kg,VT/kg)指标升高幅度显著高于对照组(P<0.05)。治疗后观察组NT-proBNP、IL-6水平降低幅度显著高于对照组(P<0.05)。与对照组比较,观察组并发症发生率显著降低(P<0.05)。结论:枸橼酸咖啡因联合PS治疗NRDS患儿临床疗效显著,与NRDS患儿肺功能提高、血清NT-proBNP、IL-6水平调节相关,可有效避免并发症发生。展开更多
PS/TiO2 composite nanospheres were prepared in situ by seed emulsion polymerization,and the structure characterization was carried out by TEM、 UV-Vis、 FTIR、 DSC＆ TGA.The tribological behaviors of PS/TiO2 nanospher...PS/TiO2 composite nanospheres were prepared in situ by seed emulsion polymerization,and the structure characterization was carried out by TEM、 UV-Vis、 FTIR、 DSC＆ TGA.The tribological behaviors of PS/TiO2 nanospheres as additives in paraffin oil were evaluated on a four-ball machine.Experimental results indicate that the PS/TiO2 composite nanospheres have a good anti-wear performance.展开更多
A shear induced ordered structure in an exfoliated polystyrene(PS)/clay nanocomposite is reported. Self\|assembly behavior was reported for the first time of a shear induced ordered structure in the nanocomposite. The...A shear induced ordered structure in an exfoliated polystyrene(PS)/clay nanocomposite is reported. Self\|assembly behavior was reported for the first time of a shear induced ordered structure in the nanocomposite. The self assembly behavior was measured by X ray diffraction(XRD) patterns, transmission electron microscopy(TEM), and FTIR dichroism technique. Compared with the broad amorphous peaks of the PS, a series of sharp XRD peaks were observed for the exturded PS/clay nanocomposite pellet sample, showing that an ordered sructure occurred under shear flow. The intensities of the four sharp XRD peaks of the ordered sructure decreased significantly with temperature. However, at 95 ℃, the XRD peaks increased significantly, the FTIR dichroism showing that and the phenyl ring of PS changed its orientation from parallel to perpendicular to the monmorillonite primary particles, whereas no obvious orientation of the alkyl chain of PS could be found. At 110 ℃, a disordered structure occurred for the phenyl ring. TEM images confirmed directly that the origin of the ordered structure was mainly due to the planar orientation of the primary particles of silicate layers as well as local ordered microsructure of the primary particles, induced by shear flow. Basd on these investigations, a possible mechanism was deduced for the formation of the ordered strucure induced by shear flow in the exfoliated PS/clay nanocomposite.展开更多
An infrared dichroism study on the orientation of PS in the shear induced ordered structure in PS/montmorillonite nanocomposite was carried out. The results showed that the phenyl ring oriented apparently parallel to ...An infrared dichroism study on the orientation of PS in the shear induced ordered structure in PS/montmorillonite nanocomposite was carried out. The results showed that the phenyl ring oriented apparently parallel to the film surface, whereas no obvious orientation of the aliphatic chain could be observed. On the basis of both of our previous and present investigations, a possible formation mechanism was presented. [WT5HZ]展开更多
文摘A shear induced ordered structure in PS/montmorillonite nanocomposite was observed for the first time by wide angle X ray diffraction technique. A transmission electron microscopy result showed that the randomly placed primary particles of montmorillonite were oriented parallel to the pellet surface, and the interior of the primary particles became more ordered as well. These results suggested that the orientation of the primary particles as well as the interior ordered structure induced by the shear flow were perhaps the origin of the ordered structure in the PS/montmorillonite nanocomposite.
文摘目的:探讨枸橼酸咖啡因联合肺表面活性物质(PS)对新生儿呼吸窘迫综合征(NRDS)患儿肺功能及血清氨基末端脑钠肽前体(amino-terminal pro-brain natriuretic peptide,NT-ProBNP)、白介素-6(inter-leukin-6,IL-6)水平的关联。方法:选2019年7月至2020年7月在我院接受治疗的NRDS患儿80例按随机数字表余数法分为观察组与对照组,每组各40例。对照组予以PS治疗,观察组在对照组基础上加用枸橼酸咖啡因。比较两组临床疗效、肺功能指标、血清NT-proBNP和IL-6水平以及并发症发生率。结果:治疗后,观察组总有效率显著高于对照组(P<0.05)。治疗后观察组达峰时间比(ratio of time to peak tidal expiratory flow and total expiratory time,TPEF/TE)、达峰容积比(ratio of expiratory volume at peak tidal expiratory flow and total expiratory volume,VPEF/VE)及每千克体重潮气量(Tidal volume/kg,VT/kg)指标升高幅度显著高于对照组(P<0.05)。治疗后观察组NT-proBNP、IL-6水平降低幅度显著高于对照组(P<0.05)。与对照组比较,观察组并发症发生率显著降低(P<0.05)。结论:枸橼酸咖啡因联合PS治疗NRDS患儿临床疗效显著,与NRDS患儿肺功能提高、血清NT-proBNP、IL-6水平调节相关,可有效避免并发症发生。
文摘PS/TiO2 composite nanospheres were prepared in situ by seed emulsion polymerization,and the structure characterization was carried out by TEM、 UV-Vis、 FTIR、 DSC＆ TGA.The tribological behaviors of PS/TiO2 nanospheres as additives in paraffin oil were evaluated on a four-ball machine.Experimental results indicate that the PS/TiO2 composite nanospheres have a good anti-wear performance.
文摘A shear induced ordered structure in an exfoliated polystyrene(PS)/clay nanocomposite is reported. Self\|assembly behavior was reported for the first time of a shear induced ordered structure in the nanocomposite. The self assembly behavior was measured by X ray diffraction(XRD) patterns, transmission electron microscopy(TEM), and FTIR dichroism technique. Compared with the broad amorphous peaks of the PS, a series of sharp XRD peaks were observed for the exturded PS/clay nanocomposite pellet sample, showing that an ordered sructure occurred under shear flow. The intensities of the four sharp XRD peaks of the ordered sructure decreased significantly with temperature. However, at 95 ℃, the XRD peaks increased significantly, the FTIR dichroism showing that and the phenyl ring of PS changed its orientation from parallel to perpendicular to the monmorillonite primary particles, whereas no obvious orientation of the alkyl chain of PS could be found. At 110 ℃, a disordered structure occurred for the phenyl ring. TEM images confirmed directly that the origin of the ordered structure was mainly due to the planar orientation of the primary particles of silicate layers as well as local ordered microsructure of the primary particles, induced by shear flow. Basd on these investigations, a possible mechanism was deduced for the formation of the ordered strucure induced by shear flow in the exfoliated PS/clay nanocomposite.
文摘An infrared dichroism study on the orientation of PS in the shear induced ordered structure in PS/montmorillonite nanocomposite was carried out. The results showed that the phenyl ring oriented apparently parallel to the film surface, whereas no obvious orientation of the aliphatic chain could be observed. On the basis of both of our previous and present investigations, a possible formation mechanism was presented. [WT5HZ]
