The corrosion behavior of C110 bushing at high temperature and high pressure with a high H2S / CO2 was studied, and a basis for the materials selection of sour gas well bushing was provided in H2S, CO2 and saline coex...The corrosion behavior of C110 bushing at high temperature and high pressure with a high H2S / CO2 was studied, and a basis for the materials selection of sour gas well bushing was provided in H2S, CO2 and saline coexisting environment. Under acidic condiction, hydrogen atoms greatly entered into the material and caused the material properties changed. Weight loss method was used to study the corrosion rate of hydrogen charging samples and original untreated samples in simulated oil field environment. PAR2273 electrochemical workstation was used to examine the electrochemical performance of samples untreated, hydrogen charging after reacting in autoclave. The corrosion product film was observed through SEM. The experimental results show that sample with hydrogen charging has a much more obvious partial corrosion and pitting corrosion than the untreated blank sample even the downhole corrosion speed of bushing is increased after being used for a period of time. Polarization curve shows the corrosion tendency is the same between sample with or without hydrogen charging and corrosion tendency is reduced by corrosion product film. A layer of dense product film formed on the surface of samples provides a certain protective effect to the matrix, but cracked holes which will accelerate partial corrosion of the sample were also observed.展开更多
为改善高钙粉煤灰在混凝土中的体积安定性和水化活性,本文对高钙粉煤灰进行了CO_(2)矿化改性,研究了不同CO_(2)矿化反应时长下高钙粉煤灰的固碳量和游离氧化钙含量,及CO_(2)矿化改性高钙粉煤灰对水泥砂浆水化热、力学性能和孔隙结构的...为改善高钙粉煤灰在混凝土中的体积安定性和水化活性,本文对高钙粉煤灰进行了CO_(2)矿化改性,研究了不同CO_(2)矿化反应时长下高钙粉煤灰的固碳量和游离氧化钙含量,及CO_(2)矿化改性高钙粉煤灰对水泥砂浆水化热、力学性能和孔隙结构的影响。结果表明,经12 h CO_(2)矿化改性处理,高钙粉煤灰固碳量可超过10%(质量分数),高钙粉煤灰中的游离氧化钙含量明显降低。随着矿化反应时间的延长,掺高钙粉煤灰的水泥浆体水化诱导期缩短,早期水化放热量明显降低。CO_(2)矿化改性处理还能减轻高钙粉煤灰对水泥砂浆强度的负面影响,改善水泥砂浆孔隙结构,降低孔隙率和大孔含量,促进水泥的早期水化和水化硅酸钙的成核结晶。展开更多
Purpose: To investigate the effects of exogenous basic fibroblast growth factor-2(FGF-2) on the biological activity of endothelial progenitor cells(EPCs) exposed to high glucose conditions. Materials and Methods: 1) B...Purpose: To investigate the effects of exogenous basic fibroblast growth factor-2(FGF-2) on the biological activity of endothelial progenitor cells(EPCs) exposed to high glucose conditions. Materials and Methods: 1) Bone marrow EPCs from C57BL/6 mice were isolated and cultured in vitro. EPC purity was identified by flow cytometry and immunofluorescence staining. 2) Apoptosis was detected by TUNEL assay. Migration and tube formation ability was detected by Transwell chamber and Matrigel assays, respectively. The expression and activation of β-catenin was detected by Western blot. 3) Doppler flowmetry was used to detect the effect of FGF2 on blood flow recovery in ischemic hind limbs of mice. Results: 1) FGF-2 treatment reversed high glucose induced growth inhibition of EPCs. FGF-2 treatment also increased migration and tube formation ability of EPCs even in high glucose conditions. 2) Western blot analysis demonstrated that the percentage of activated β-catenin/total β-catenin in the high glucose group were significantly lower than that in the control group, while FGF-2 treatment reversed high glucose induced β-catenin inhibition. 3) In vivo experiments demonstrated that the blood flow recovery in ischemic hind limbs of mice was significantly improved after FGF-2 treatment. Conclusion: Exogenous FGF-2 could play a role in the functional repair of damaged EPC exposed to high glucose conditions, via the activation of the Wnt/β-catenin signaling pathway.展开更多
The corrosion behavior of the 110S tube steel in the environments of high H2 S and CO2 content was inves- tigated by using a high-temperature and high-pressure autoclave, and the corrosion products were characterized ...The corrosion behavior of the 110S tube steel in the environments of high H2 S and CO2 content was inves- tigated by using a high-temperature and high-pressure autoclave, and the corrosion products were characterized by scanning electron microscopy and X ray diffraction technique. The results showed that all of the corrosion products under the test conditions mainly consisted of different types of iron sulfides such as pyrrhotite of Fe0.95 S, mackinaw- ite of FeS0.9, Fe0. 985 S and FeS, and the absence of iron carbonate in the corrosion scales indicated that the corrosion process was controlled by H2S corrosion. The corrosion rate of the 110S steel decreased firstly and then increased with the rising of temperature. The minimum corrosion rate occurred at 110 ℃. When the H2 S partial pressure PH2s below 9 MPa, the corrosion rate declined with the increase of PH2s. While over 9 MPa, a higher PH2s resulted in a faster corrosion process. With the increasing of the CO2 partial pressure, the corrosion rate had an increasing trend. The morphologies of the corrosion scales had a good accordance with the corrosion rates.展开更多
研究强磁重力环境对人成骨细胞MG-63中发动蛋白-2表达和分布的影响。采用大梯度超导磁体模拟空间重力环境,该超导磁体可以提供3种不同的强磁重力环境(high magnetic gravitational environment,HMGE),即0g(12T),1g(16T)和2g(12T)。将MG...研究强磁重力环境对人成骨细胞MG-63中发动蛋白-2表达和分布的影响。采用大梯度超导磁体模拟空间重力环境,该超导磁体可以提供3种不同的强磁重力环境(high magnetic gravitational environment,HMGE),即0g(12T),1g(16T)和2g(12T)。将MG-63细胞分别在0g(12T)、1g(16T)、2g(12T)及对照环境(1g,地磁)中培养24h后,采用Real Time PCR、Western印迹以及激光扫描共聚焦显微术等方法检测HMGE对发动蛋白-2的表达及定位的影响。结果显示,与对照组相比,0g(12T)、1g(16T)、2g(12T)环境处理组MG-63细胞中发动蛋白-2在mRNA上的表达量分别上调6.43、15.57、1.29倍;在蛋白质水平上,0g(12T)、1g(16T)环境处理组细胞发动蛋白-2分别上调89%和7%,而2g(12T)环境处理组则下调41%;在对照组中发动蛋白-2弥散分布于细胞质中,而0g(12T)处理组发动蛋白-2则有从细胞边缘向核周集中的趋势。上述结果说明强磁重力环境影响了发动蛋白-2在MG-63细胞中的表达和定位。展开更多
化石燃料的大规模使用造成了CO_(2)排放量逐年递增,其作为温室气体的主要成分加速了全球变暖及气候变化。CO_(2)的捕集、利用与存储(Carbon Capture,Utilization and Storage,简称CCUS)技术作为降低碳排放的有效方法,受到广泛关注。在...化石燃料的大规模使用造成了CO_(2)排放量逐年递增,其作为温室气体的主要成分加速了全球变暖及气候变化。CO_(2)的捕集、利用与存储(Carbon Capture,Utilization and Storage,简称CCUS)技术作为降低碳排放的有效方法,受到广泛关注。在诸多减少CO_(2)排放量的方法中,吸附法分离脱除CO_(2)具备良好的应用前景。固体吸附材料具有操作温度广、不易腐蚀设备、循环使用过程中产生的废物较少且易于处理等优点,被认为是理想的CO_(2)捕集材料。综述了3种类型的CO_(2)固体吸附剂的研究进展,包括低温、中温和高温固体吸附剂,指出了其优点和局限性及强化CO_(2)吸附性能与循环稳定性的措施。通常来说高压对低温固体吸附剂更加有利,但此条件下其选择性较差,且气流中存在的水分会水解某些吸附剂中的配位键,并与CO_(2)产生竞争吸附,导致CO_(2)吸附性能下降。因此低温吸附剂的吸附能力、吸附选择性和水热稳定性是研究重点。中温固体吸附剂中,类水滑石材料面临的挑战在于其独特的氢键堆积结构限制了其吸附容量进一步提高,而MgO吸附剂由于缺少基础活性位点以及固有的高晶格焓同样导致其吸附性能与吸附动力学较差。故中温吸附剂需要优先解决其低吸附能力和低循环稳定性的问题。高温固体吸附剂中,Li_(4)SiO_(4)吸附剂相比于Li_(2)ZrO_(3)吸附剂具备更低的制备成本以及更高的吸附容量,但2者皆面临动力学限制问题。CaO基吸附剂由于其理论吸附容量高、适用范围广、成本低廉、无毒、具备快速的吸附动力学特性等优点受到广泛关注。而在CO_(2)吸附/脱附多循环过程中,钙基吸附剂由颗粒烧结引发的热失活以及颗粒磨损问题是限制其进一步发展的最大障碍。针对这些问题可采用高温预处理、水合作用、化学掺杂、酸改性等方式来提高其吸附性能与多循环稳定性。此外,造粒及规模化制备技术是提高其工业应用潜力需解决的瓶颈问题。展开更多
In atherosclerosis,chronic inflammatory processes in local diseased areas may lead to the accumulation of reactive oxygen species(ROS).In this study,we devised a highly sensitive H_(2)O_(2)-scavenging nanobionic syste...In atherosclerosis,chronic inflammatory processes in local diseased areas may lead to the accumulation of reactive oxygen species(ROS).In this study,we devised a highly sensitive H_(2)O_(2)-scavenging nanobionic system loaded with probucol(RPP-PU),to treat atherosclerosis more effectively.The RPP material had high sensitivity to H_(2)O_(2),and the response sensitivity could be reduced from 40 to 10μmol/L which was close to the lowest concentration of H_(2)O_(2)levels of the pathological environment.RPP-PU delayed the release and prolonged the duration of PU in vivo.In Apolipoprotein E deficient(ApoE-/-)mice,RPP-PU effectively eliminated pathological ROS,reduced the level of lipids and related metabolic enzymes,and significantly decreased the area of vascular plaques and fibers.Our study demonstrated that the H_(2)O_(2)-scavenging nanobionic system could scavenge the abundant ROS in the atherosclerosis lesion,thereby reducing the oxidative stress for treating atherosclerosis and thus achieve the therapeutic goals with atherosclerosis more desirably.展开更多
基金Funded by the National Natural Science Foundation of China(No. 50904050)the Basic Projects of Sichuan Province(2011JY0106)the Postdoctoral Science Foundation(20110490810)
文摘The corrosion behavior of C110 bushing at high temperature and high pressure with a high H2S / CO2 was studied, and a basis for the materials selection of sour gas well bushing was provided in H2S, CO2 and saline coexisting environment. Under acidic condiction, hydrogen atoms greatly entered into the material and caused the material properties changed. Weight loss method was used to study the corrosion rate of hydrogen charging samples and original untreated samples in simulated oil field environment. PAR2273 electrochemical workstation was used to examine the electrochemical performance of samples untreated, hydrogen charging after reacting in autoclave. The corrosion product film was observed through SEM. The experimental results show that sample with hydrogen charging has a much more obvious partial corrosion and pitting corrosion than the untreated blank sample even the downhole corrosion speed of bushing is increased after being used for a period of time. Polarization curve shows the corrosion tendency is the same between sample with or without hydrogen charging and corrosion tendency is reduced by corrosion product film. A layer of dense product film formed on the surface of samples provides a certain protective effect to the matrix, but cracked holes which will accelerate partial corrosion of the sample were also observed.
文摘为改善高钙粉煤灰在混凝土中的体积安定性和水化活性,本文对高钙粉煤灰进行了CO_(2)矿化改性,研究了不同CO_(2)矿化反应时长下高钙粉煤灰的固碳量和游离氧化钙含量,及CO_(2)矿化改性高钙粉煤灰对水泥砂浆水化热、力学性能和孔隙结构的影响。结果表明,经12 h CO_(2)矿化改性处理,高钙粉煤灰固碳量可超过10%(质量分数),高钙粉煤灰中的游离氧化钙含量明显降低。随着矿化反应时间的延长,掺高钙粉煤灰的水泥浆体水化诱导期缩短,早期水化放热量明显降低。CO_(2)矿化改性处理还能减轻高钙粉煤灰对水泥砂浆强度的负面影响,改善水泥砂浆孔隙结构,降低孔隙率和大孔含量,促进水泥的早期水化和水化硅酸钙的成核结晶。
基金This study was supported by grants from the General Programs of the National Natural Science Foundation of China(No.8157070468)
文摘Purpose: To investigate the effects of exogenous basic fibroblast growth factor-2(FGF-2) on the biological activity of endothelial progenitor cells(EPCs) exposed to high glucose conditions. Materials and Methods: 1) Bone marrow EPCs from C57BL/6 mice were isolated and cultured in vitro. EPC purity was identified by flow cytometry and immunofluorescence staining. 2) Apoptosis was detected by TUNEL assay. Migration and tube formation ability was detected by Transwell chamber and Matrigel assays, respectively. The expression and activation of β-catenin was detected by Western blot. 3) Doppler flowmetry was used to detect the effect of FGF2 on blood flow recovery in ischemic hind limbs of mice. Results: 1) FGF-2 treatment reversed high glucose induced growth inhibition of EPCs. FGF-2 treatment also increased migration and tube formation ability of EPCs even in high glucose conditions. 2) Western blot analysis demonstrated that the percentage of activated β-catenin/total β-catenin in the high glucose group were significantly lower than that in the control group, while FGF-2 treatment reversed high glucose induced β-catenin inhibition. 3) In vivo experiments demonstrated that the blood flow recovery in ischemic hind limbs of mice was significantly improved after FGF-2 treatment. Conclusion: Exogenous FGF-2 could play a role in the functional repair of damaged EPC exposed to high glucose conditions, via the activation of the Wnt/β-catenin signaling pathway.
基金Sponsored by Key National Science and Technology Specific Projects of China(2008ZX05017-002)
文摘The corrosion behavior of the 110S tube steel in the environments of high H2 S and CO2 content was inves- tigated by using a high-temperature and high-pressure autoclave, and the corrosion products were characterized by scanning electron microscopy and X ray diffraction technique. The results showed that all of the corrosion products under the test conditions mainly consisted of different types of iron sulfides such as pyrrhotite of Fe0.95 S, mackinaw- ite of FeS0.9, Fe0. 985 S and FeS, and the absence of iron carbonate in the corrosion scales indicated that the corrosion process was controlled by H2S corrosion. The corrosion rate of the 110S steel decreased firstly and then increased with the rising of temperature. The minimum corrosion rate occurred at 110 ℃. When the H2 S partial pressure PH2s below 9 MPa, the corrosion rate declined with the increase of PH2s. While over 9 MPa, a higher PH2s resulted in a faster corrosion process. With the increasing of the CO2 partial pressure, the corrosion rate had an increasing trend. The morphologies of the corrosion scales had a good accordance with the corrosion rates.
文摘研究强磁重力环境对人成骨细胞MG-63中发动蛋白-2表达和分布的影响。采用大梯度超导磁体模拟空间重力环境,该超导磁体可以提供3种不同的强磁重力环境(high magnetic gravitational environment,HMGE),即0g(12T),1g(16T)和2g(12T)。将MG-63细胞分别在0g(12T)、1g(16T)、2g(12T)及对照环境(1g,地磁)中培养24h后,采用Real Time PCR、Western印迹以及激光扫描共聚焦显微术等方法检测HMGE对发动蛋白-2的表达及定位的影响。结果显示,与对照组相比,0g(12T)、1g(16T)、2g(12T)环境处理组MG-63细胞中发动蛋白-2在mRNA上的表达量分别上调6.43、15.57、1.29倍;在蛋白质水平上,0g(12T)、1g(16T)环境处理组细胞发动蛋白-2分别上调89%和7%,而2g(12T)环境处理组则下调41%;在对照组中发动蛋白-2弥散分布于细胞质中,而0g(12T)处理组发动蛋白-2则有从细胞边缘向核周集中的趋势。上述结果说明强磁重力环境影响了发动蛋白-2在MG-63细胞中的表达和定位。
文摘化石燃料的大规模使用造成了CO_(2)排放量逐年递增,其作为温室气体的主要成分加速了全球变暖及气候变化。CO_(2)的捕集、利用与存储(Carbon Capture,Utilization and Storage,简称CCUS)技术作为降低碳排放的有效方法,受到广泛关注。在诸多减少CO_(2)排放量的方法中,吸附法分离脱除CO_(2)具备良好的应用前景。固体吸附材料具有操作温度广、不易腐蚀设备、循环使用过程中产生的废物较少且易于处理等优点,被认为是理想的CO_(2)捕集材料。综述了3种类型的CO_(2)固体吸附剂的研究进展,包括低温、中温和高温固体吸附剂,指出了其优点和局限性及强化CO_(2)吸附性能与循环稳定性的措施。通常来说高压对低温固体吸附剂更加有利,但此条件下其选择性较差,且气流中存在的水分会水解某些吸附剂中的配位键,并与CO_(2)产生竞争吸附,导致CO_(2)吸附性能下降。因此低温吸附剂的吸附能力、吸附选择性和水热稳定性是研究重点。中温固体吸附剂中,类水滑石材料面临的挑战在于其独特的氢键堆积结构限制了其吸附容量进一步提高,而MgO吸附剂由于缺少基础活性位点以及固有的高晶格焓同样导致其吸附性能与吸附动力学较差。故中温吸附剂需要优先解决其低吸附能力和低循环稳定性的问题。高温固体吸附剂中,Li_(4)SiO_(4)吸附剂相比于Li_(2)ZrO_(3)吸附剂具备更低的制备成本以及更高的吸附容量,但2者皆面临动力学限制问题。CaO基吸附剂由于其理论吸附容量高、适用范围广、成本低廉、无毒、具备快速的吸附动力学特性等优点受到广泛关注。而在CO_(2)吸附/脱附多循环过程中,钙基吸附剂由颗粒烧结引发的热失活以及颗粒磨损问题是限制其进一步发展的最大障碍。针对这些问题可采用高温预处理、水合作用、化学掺杂、酸改性等方式来提高其吸附性能与多循环稳定性。此外,造粒及规模化制备技术是提高其工业应用潜力需解决的瓶颈问题。
基金supported by grants from the National Natural Science Funds of China(31771097,82072080,82070301)CAMS Innovation Fund for Medical Sciences(CIFMS,2021I2M-1-058,China)supported by Special Program for High-Tech Leader&Team of Tianjin Government and Tianjin Innovation Promotion Plan Key Innovation Team of Immunoreactive Biomaterials。
文摘In atherosclerosis,chronic inflammatory processes in local diseased areas may lead to the accumulation of reactive oxygen species(ROS).In this study,we devised a highly sensitive H_(2)O_(2)-scavenging nanobionic system loaded with probucol(RPP-PU),to treat atherosclerosis more effectively.The RPP material had high sensitivity to H_(2)O_(2),and the response sensitivity could be reduced from 40 to 10μmol/L which was close to the lowest concentration of H_(2)O_(2)levels of the pathological environment.RPP-PU delayed the release and prolonged the duration of PU in vivo.In Apolipoprotein E deficient(ApoE-/-)mice,RPP-PU effectively eliminated pathological ROS,reduced the level of lipids and related metabolic enzymes,and significantly decreased the area of vascular plaques and fibers.Our study demonstrated that the H_(2)O_(2)-scavenging nanobionic system could scavenge the abundant ROS in the atherosclerosis lesion,thereby reducing the oxidative stress for treating atherosclerosis and thus achieve the therapeutic goals with atherosclerosis more desirably.