目的探讨16排螺旋CT行胸部血管造影检查时图像质量与碘造影剂注射流速的相关性。方法选取自2013年10月—2016年9月在该科行胸部CT检查老年患者90例,随机分为A1、A2、A3 3组,每组30例。3组流速分别为2.0~2.4、2.5~2.8、2.9~3.2 m L/s。...目的探讨16排螺旋CT行胸部血管造影检查时图像质量与碘造影剂注射流速的相关性。方法选取自2013年10月—2016年9月在该科行胸部CT检查老年患者90例,随机分为A1、A2、A3 3组,每组30例。3组流速分别为2.0~2.4、2.5~2.8、2.9~3.2 m L/s。观察分析肺动脉平均强化值,图像质量。结果 3组行CT检查后的效果评价A1,A2,A3组的肺动脉平均强化值分别为(195.9±29.1),(262.20±59.0),(255.9±53.2),3组造影效果主动脉强化值差异有统计学意义(P<0.01),3组不同流速碘造影剂的图像质量差异有统计学意义(P<0.01)。结论老年患者在行胸部CT增强扫描碘造影剂注射流速在2.5~2.8 m L/s时,获得的图像较满意,并能满足临床诊断需要,且能保护患者穿刺血管的安全。展开更多
Two kinds of simulated concrete pore solutions(SPSs) were treated with different amounts of synthetic calcium silicate hydrate(C-S-H). The variation of the [Cl^-]/[OH^-] ratio in SPS was measured and the corrosion...Two kinds of simulated concrete pore solutions(SPSs) were treated with different amounts of synthetic calcium silicate hydrate(C-S-H). The variation of the [Cl^-]/[OH^-] ratio in SPS was measured and the corrosion susceptibility of carbon steel in the SPS was investigated with potentiodynamic polarization, EIS and weight lose tests. The experimental results showed that for the SPS at p H 12.5, as the amount of C-S-H increases, the [Cl^-]/[OH^-] ratio increases thereby causing an increase in the corrosion susceptibility of the steel. While for the SPS at p H 9.7, with increasing C-S-H amount, the drop amplitudes of both [Cl^-]/[OH^-] ratio and steel corrosion rate first decrease and then increase, and a 3% C-S-H addition shows the best inhibition effect. XPS results demonstrate that after C-S-H treating in p H 12.5 SPS the [Fe^(3+)]/[Fe^(2+)] ratio in the film on steel surface is reduced while in p H 9.7 SPS the [Fe^(3+)]/[Fe^(2+)] ratio is increased. The different effects of the C-S-H amount on the two SPSs and the steel corrosion behavior result from the influences of C-S-H on the SPS p H, which is related to the composition of the SPS.展开更多
本文研究了夏石金花茶(Camellia xiashiensis S. Y. Liang et C. Z. Deng, sp. nov. ined)的核型。结果表明:其体细胞染色体数目为2n=30,具12对中部着丝点染色体.5对近中部着丝点染色体,第15对染色体具1对随体。根据Levan等的分类原则...本文研究了夏石金花茶(Camellia xiashiensis S. Y. Liang et C. Z. Deng, sp. nov. ined)的核型。结果表明:其体细胞染色体数目为2n=30,具12对中部着丝点染色体.5对近中部着丝点染色体,第15对染色体具1对随体。根据Levan等的分类原则。其核型为2n=2x=24m(2SAT)+6sm。属于Stebbins核型的“2A”型。展开更多
文摘目的探讨16排螺旋CT行胸部血管造影检查时图像质量与碘造影剂注射流速的相关性。方法选取自2013年10月—2016年9月在该科行胸部CT检查老年患者90例,随机分为A1、A2、A3 3组,每组30例。3组流速分别为2.0~2.4、2.5~2.8、2.9~3.2 m L/s。观察分析肺动脉平均强化值,图像质量。结果 3组行CT检查后的效果评价A1,A2,A3组的肺动脉平均强化值分别为(195.9±29.1),(262.20±59.0),(255.9±53.2),3组造影效果主动脉强化值差异有统计学意义(P<0.01),3组不同流速碘造影剂的图像质量差异有统计学意义(P<0.01)。结论老年患者在行胸部CT增强扫描碘造影剂注射流速在2.5~2.8 m L/s时,获得的图像较满意,并能满足临床诊断需要,且能保护患者穿刺血管的安全。
基金Funded by the National Natural Science Foundation of China(Nos.51171014 and 51210001)
文摘Two kinds of simulated concrete pore solutions(SPSs) were treated with different amounts of synthetic calcium silicate hydrate(C-S-H). The variation of the [Cl^-]/[OH^-] ratio in SPS was measured and the corrosion susceptibility of carbon steel in the SPS was investigated with potentiodynamic polarization, EIS and weight lose tests. The experimental results showed that for the SPS at p H 12.5, as the amount of C-S-H increases, the [Cl^-]/[OH^-] ratio increases thereby causing an increase in the corrosion susceptibility of the steel. While for the SPS at p H 9.7, with increasing C-S-H amount, the drop amplitudes of both [Cl^-]/[OH^-] ratio and steel corrosion rate first decrease and then increase, and a 3% C-S-H addition shows the best inhibition effect. XPS results demonstrate that after C-S-H treating in p H 12.5 SPS the [Fe^(3+)]/[Fe^(2+)] ratio in the film on steel surface is reduced while in p H 9.7 SPS the [Fe^(3+)]/[Fe^(2+)] ratio is increased. The different effects of the C-S-H amount on the two SPSs and the steel corrosion behavior result from the influences of C-S-H on the SPS p H, which is related to the composition of the SPS.
文摘本文研究了夏石金花茶(Camellia xiashiensis S. Y. Liang et C. Z. Deng, sp. nov. ined)的核型。结果表明:其体细胞染色体数目为2n=30,具12对中部着丝点染色体.5对近中部着丝点染色体,第15对染色体具1对随体。根据Levan等的分类原则。其核型为2n=2x=24m(2SAT)+6sm。属于Stebbins核型的“2A”型。