Several drawing processes of 3N pure copper (Cu) with ultra high reduction in area have been performed, and the texture has been observed using electron back scattered diffraction. It is well known that the texture of...Several drawing processes of 3N pure copper (Cu) with ultra high reduction in area have been performed, and the texture has been observed using electron back scattered diffraction. It is well known that the texture of drawn Cu is closely related to its mechanical properties;in particular nanometer scale width fibber shaped grain is interesting. Previously, it was reported that drawing 3N Cu with around 95% reduction in area changes its mechanical properties. In the present experiment, grains have been changed from round to fiber-shaped, and subsequently, submicron-width fiber grains were generated with a 94.546% reduction in area. However, above 94.546% reduction in area, dynamic recrystallization occurred and then, prevented the grains to be finer. Further recrystallized grains influence on the macroscopic mechanical properties of Cu wire. Furthermore, the distribution of the misorientation angle at grain boundaries increased with an increase in the degree of reduction in area;in particular, the distribution drastically increased between 94.546% and 99.997%. Further, the frequency of coincidence of site lattice boundaries increased. The abovementioned variations in texture are closely related to mechanical properties.展开更多
The based membrane extraction of Th 4+ and Yb 3+ was studied in HBTMPP heptane using a hollow fibber membrane. The separation method of Th 4+ and Yb 3+ was proposed by kinetics competition. The se...The based membrane extraction of Th 4+ and Yb 3+ was studied in HBTMPP heptane using a hollow fibber membrane. The separation method of Th 4+ and Yb 3+ was proposed by kinetics competition. The separation operation of Th 4+ and Yb 3+ mixture was carried out by two successive extraction and stripping simultaneously. The concentration ratio of Th 4+ to Yb 3+ is 16 74 in the stripping solution. The recovery and purity of Th 4+ are 71 6% and 95 74% respectively.展开更多
Geopolymers,such as phosphate-based geopolymer,are promising materials that have drawn extensive attentions as wave-transparent candidates with low dielectric loss factor.In this paper,multilayer SiO2fibers are introd...Geopolymers,such as phosphate-based geopolymer,are promising materials that have drawn extensive attentions as wave-transparent candidates with low dielectric loss factor.In this paper,multilayer SiO2fibers are introduced into phosphate-based geopolymer matrix to prepare composites.Crack generation and fracture behaviors during the three-point bending tests in as-prepared SiO2f/phosphate geopolymer composites are clarified by in situ observation Before high-temperature treatment,composite with 17 vol%fiber content exhibits the best mechanical properties.A decreasing mechanical strength is observed after being treated at higher temperature,which is attributed to the stronger interface binging between fibers and phosphatebased geopolymer matrix.Most importantly,the presence of SiO2fibers can strengthen mechanical properties of phosphate-based geopolymer matrix but shows negligible impact on its dielectric properties,achieving dielectric loss factor as low as 3.53910-3after being treated at 700°C.展开更多
文摘Several drawing processes of 3N pure copper (Cu) with ultra high reduction in area have been performed, and the texture has been observed using electron back scattered diffraction. It is well known that the texture of drawn Cu is closely related to its mechanical properties;in particular nanometer scale width fibber shaped grain is interesting. Previously, it was reported that drawing 3N Cu with around 95% reduction in area changes its mechanical properties. In the present experiment, grains have been changed from round to fiber-shaped, and subsequently, submicron-width fiber grains were generated with a 94.546% reduction in area. However, above 94.546% reduction in area, dynamic recrystallization occurred and then, prevented the grains to be finer. Further recrystallized grains influence on the macroscopic mechanical properties of Cu wire. Furthermore, the distribution of the misorientation angle at grain boundaries increased with an increase in the degree of reduction in area;in particular, the distribution drastically increased between 94.546% and 99.997%. Further, the frequency of coincidence of site lattice boundaries increased. The abovementioned variations in texture are closely related to mechanical properties.
文摘The based membrane extraction of Th 4+ and Yb 3+ was studied in HBTMPP heptane using a hollow fibber membrane. The separation method of Th 4+ and Yb 3+ was proposed by kinetics competition. The separation operation of Th 4+ and Yb 3+ mixture was carried out by two successive extraction and stripping simultaneously. The concentration ratio of Th 4+ to Yb 3+ is 16 74 in the stripping solution. The recovery and purity of Th 4+ are 71 6% and 95 74% respectively.
基金financially supported by the National Natural Science Foundation of China(Nos.518720635150205251832002 and 51621091)。
文摘Geopolymers,such as phosphate-based geopolymer,are promising materials that have drawn extensive attentions as wave-transparent candidates with low dielectric loss factor.In this paper,multilayer SiO2fibers are introduced into phosphate-based geopolymer matrix to prepare composites.Crack generation and fracture behaviors during the three-point bending tests in as-prepared SiO2f/phosphate geopolymer composites are clarified by in situ observation Before high-temperature treatment,composite with 17 vol%fiber content exhibits the best mechanical properties.A decreasing mechanical strength is observed after being treated at higher temperature,which is attributed to the stronger interface binging between fibers and phosphatebased geopolymer matrix.Most importantly,the presence of SiO2fibers can strengthen mechanical properties of phosphate-based geopolymer matrix but shows negligible impact on its dielectric properties,achieving dielectric loss factor as low as 3.53910-3after being treated at 700°C.
