The corrosion behavior of expandable tubular materials was investigated in simulated downhole formation water environments using a series of electrochemical techniques. The corrosion morphologies in the real downhole ...The corrosion behavior of expandable tubular materials was investigated in simulated downhole formation water environments using a series of electrochemical techniques. The corrosion morphologies in the real downhole environment after three months of application were also observed by stereology microscopy and scanning electron microscopy (SEM). The results show that, compared with the unex- panded sample, the area of ferfite increases dramatically after a 7.09% expansion. The expanded material shows a higher corrosion current in the polarization curve and a lower corrosion resistance in the electrochemical impedance spectroscopy (EIS) plot at every studied tempera- ture. The determined critical pitting temperatures (CPT) before and after expansion are 87.5℃and 79.2℃, respectively. SEM observations demonstrate stress corrosion cracks, and CO2 corrosion and H2S corrosion also occur in the downhole environment. Due to additional defects generated during the plastic deformation, the corrosion performance of the expanded tubing deteriorates.展开更多
Objective: To explore the clinical significance of the quantitative detection of human papillomavirus(HPV) E6/E7 mRN A in triage of patients with atypical squamous cells of undetermined significance(ASC-US) and low-gr...Objective: To explore the clinical significance of the quantitative detection of human papillomavirus(HPV) E6/E7 mRN A in triage of patients with atypical squamous cells of undetermined significance(ASC-US) and low-grade squamous intraepithelial lesion(LSIL).Methods: A cross-sectional screening study was conducted among women who underwent outpatient gynecological screening at the Obstetrics and Gynecology Hospital of Fudan University from September 2015 to July 2016. A total of 500 patients from our hospital with ASC-US or LSIL based on cytology testing were subjected to HPV DNA and HPV E6/E7 mRNA quantitative analysis.Results: The specificity of the HPV E6/E7 mRNA test for detecting ≥high-grade squamous intraepithelial lesion(HSIL+) was statistically higher than that of the HPV DNA test(61.3% vs. 40.0%, P< 0.05), whereas there was no significant difference in the sensitivity of HPV E6/E7 mRNA test and HPV DNA test(90.0% vs. 95.0%, P > 0.05). The positive rates of HPV in the participants tested by HPV E6/E7 mRNA and HPV DNA were, respectively, 42.8%(214/500) and 62.8%(314/500), with statistical significance(P < 0.05).Conclusions: The HPV E6/E7 mRNA test was slightly less sensitivity than that of the HPV DNA test for diagnosing HSIL+ in patients with ASC-US and LSIL, but the difference was not significant, although the specificity of the former was significantly higher. HPV E6/E7 mRNA detection can effectively reduce overdiagnosis and overtreatment of patients with ASC-US and LSIL and has important clinical value in triage of patients with ASC-US and LSIL.展开更多
基金financially supported by the National Natural Science Foundation of China(No.51222106)the Fundamental Research Funds for the Central Universities of China(No.FRF-TP-14-011C1)
文摘The corrosion behavior of expandable tubular materials was investigated in simulated downhole formation water environments using a series of electrochemical techniques. The corrosion morphologies in the real downhole environment after three months of application were also observed by stereology microscopy and scanning electron microscopy (SEM). The results show that, compared with the unex- panded sample, the area of ferfite increases dramatically after a 7.09% expansion. The expanded material shows a higher corrosion current in the polarization curve and a lower corrosion resistance in the electrochemical impedance spectroscopy (EIS) plot at every studied tempera- ture. The determined critical pitting temperatures (CPT) before and after expansion are 87.5℃and 79.2℃, respectively. SEM observations demonstrate stress corrosion cracks, and CO2 corrosion and H2S corrosion also occur in the downhole environment. Due to additional defects generated during the plastic deformation, the corrosion performance of the expanded tubing deteriorates.
基金supported by the Shanghai Science and Technology Committee Project(No.16411950200).
文摘Objective: To explore the clinical significance of the quantitative detection of human papillomavirus(HPV) E6/E7 mRN A in triage of patients with atypical squamous cells of undetermined significance(ASC-US) and low-grade squamous intraepithelial lesion(LSIL).Methods: A cross-sectional screening study was conducted among women who underwent outpatient gynecological screening at the Obstetrics and Gynecology Hospital of Fudan University from September 2015 to July 2016. A total of 500 patients from our hospital with ASC-US or LSIL based on cytology testing were subjected to HPV DNA and HPV E6/E7 mRNA quantitative analysis.Results: The specificity of the HPV E6/E7 mRNA test for detecting ≥high-grade squamous intraepithelial lesion(HSIL+) was statistically higher than that of the HPV DNA test(61.3% vs. 40.0%, P< 0.05), whereas there was no significant difference in the sensitivity of HPV E6/E7 mRNA test and HPV DNA test(90.0% vs. 95.0%, P > 0.05). The positive rates of HPV in the participants tested by HPV E6/E7 mRNA and HPV DNA were, respectively, 42.8%(214/500) and 62.8%(314/500), with statistical significance(P < 0.05).Conclusions: The HPV E6/E7 mRNA test was slightly less sensitivity than that of the HPV DNA test for diagnosing HSIL+ in patients with ASC-US and LSIL, but the difference was not significant, although the specificity of the former was significantly higher. HPV E6/E7 mRNA detection can effectively reduce overdiagnosis and overtreatment of patients with ASC-US and LSIL and has important clinical value in triage of patients with ASC-US and LSIL.