以十二烷基甜菜碱和脂肪酸酰胺两种表面活性剂为主要原料,研发了一种高活性、耐温、抗盐、超低界面张力的表面活性剂C S-6.实验结果表明:在40℃~80℃、矿化度10000~100000 m g/L、表面活性剂溶液浓度0.3%~0.6%的情况下,油...以十二烷基甜菜碱和脂肪酸酰胺两种表面活性剂为主要原料,研发了一种高活性、耐温、抗盐、超低界面张力的表面活性剂C S-6.实验结果表明:在40℃~80℃、矿化度10000~100000 m g/L、表面活性剂溶液浓度0.3%~0.6%的情况下,油水间的界面张力均可达10-4 mN/m 数量级.同时该表面活性剂体系具有较好的乳化能力,且抗吸附性强,驱替实验效果良好.展开更多
针对低渗透油藏注入性差、洗油效率低,水驱无法有效提高采收率等问题,提出了一种低界面张力小分子驱油剂(LST溶液)提高低渗透油藏采收率新技术,评价了该驱油剂的界面活性、增黏性、乳化性、润湿性及其油藏环境适应性和驱油效果。结果表...针对低渗透油藏注入性差、洗油效率低,水驱无法有效提高采收率等问题,提出了一种低界面张力小分子驱油剂(LST溶液)提高低渗透油藏采收率新技术,评价了该驱油剂的界面活性、增黏性、乳化性、润湿性及其油藏环境适应性和驱油效果。结果表明,该驱油剂具有良好的界面活性和增黏性。在6788.23 mg/L的矿化水中,质量分数为0.4%时的LST溶液的油水界面张力为0.012 m N/m,且黏度与油藏原油黏度(3.4 m Pa·s)相近。LST溶液具有较好的油水乳化能力,可改善油藏水润湿性。在47.2℃、油水比为1∶1的条件下,LST乳状液的稳定时间为120 min。岩心经LST溶液处理后,水相接触角由57.0°降至12.5°,油相接触角由24.3°增至38.6°。LST溶液具有良好的静态抗吸附性能,经岩心3次吸附后,LST残液与原油间的界面张力仍能达到10^(-2)m N/m数量级,黏度达2.895 m Pa·s,乳状液静置10、120 min的析水率分别为38.6%、73.4%。LST溶液的耐盐性能较好。在矿化度为16570 mg/L的环境下,其油水界面张力低于7×10^(-2)m N/m、黏度为3.06 m Pa·s。LST溶液的驱油效果较好,可有效封堵高渗透孔道,启动低渗透孔道残余油。注入0.4 PV 0.4%LST溶液可使均质岩心(0.05μm^(2))的水驱驱油效率提高11.21百分点,非均质岩心(级差3~10)水驱后的综合采收率提高6.55百分点~19.41百分点。LST溶液可以实现低剂量或低成本有效提高水驱采收率,在低渗透非均质油藏化学驱提高采收率方面具有较好的应用前景。展开更多
Stability of Defibrase in various pH buffer solutions was investigated. Enzyme-linked immuno-sorbent assay (ELISA) and coagulating time method were used to assess antigenic stability and coagulating stability, respect...Stability of Defibrase in various pH buffer solutions was investigated. Enzyme-linked immuno-sorbent assay (ELISA) and coagulating time method were used to assess antigenic stability and coagulating stability, respectively. The change of antigenic activities and coagulating activities of Defibrase in the same buffer solutions (pH 6, 7 and 8, with the exception of pH 3.6) showed similar tendency to decline with the time. Concentrated Defi-brase was relatively stable at neutral pH 6~7, more than 95% of its initial activities (100BUmL-1) was kept after a 10-day storage at 40 oC, whereas in pH 3.6 and pH 9 buffer solutions, diluted Defibrase was very labile. Addition of Triton X-100 or bovine serum albumin could effectively prevent loss of Defibrase by minimizing adsorption of De-fibrase to plastic surface (P<0.005). Concentration of Defibrase could also affect its stability in aqueous solutions.展开更多
The contents of total phenolics and extractable condensed tannins in the leaves, twigs and stem bark of Canarium album were determined. The structural heterogeneity of condensed tannins from stem bark was characterize...The contents of total phenolics and extractable condensed tannins in the leaves, twigs and stem bark of Canarium album were determined. The structural heterogeneity of condensed tannins from stem bark was characterized by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and nuclear magnetic resonance (NMR) analyses The results show the predominance of signals representative of procyanidins and prodelphinidins. In addition, epicatechin and epigallocatechin polymers with galloylated procyanidin or prodelphinidin were also observed. The tannins were screened for their potential antioxidant activities using l,l-diphenyl-2-picrylhydrazyl (DPPH) and ferric reducing/antioxidant power (FRAP) model systems. Tannins extracted from leaves, twigs and stem bark all showed a very good DPPH radical scavenging activity and ferric reducing power.展开更多
The. objectives.of this study are to convert at laboratory s.cale agric.ultural residues into activated carbons (AC) with specific properties, to characterize them and to test them in adsorption reactor for tetracyc...The. objectives.of this study are to convert at laboratory s.cale agric.ultural residues into activated carbons (AC) with specific properties, to characterize them and to test them in adsorption reactor for tetracycline removal, a common antibiotic. Two new ACs were produced by direct activation with steam from beet pulp (BP-H2O) and peanut hu_lls (PH-H2O) in environmental friendly conditions BP-H2O and PH-H2Opresentcarbon content rangedcarbons with different intrinsic properties.展开更多
Objective:The aim of this study was to prepare monoclonal antibody against P53, a kind of tumor suppressor protein,and use the antibody initial y in clinical immunoassay. Methods:Monoclonal antibody was prepared and...Objective:The aim of this study was to prepare monoclonal antibody against P53, a kind of tumor suppressor protein,and use the antibody initial y in clinical immunoassay. Methods:Monoclonal antibody was prepared and identified via the classic protocol of monoclonal antibody preparation. Identified monoclonal antibodies were purified by af inity chro-matography. Antibody titer was determined by enzyme linked immunosorbent assay (ELISA). The specific binding activity of antibody was detected by Western blotting and immunohistochemistry. Results:Three strains of monoclonal antibodies named 1P15, 2P37 and 3P40 were obtained and purified by af inity chromatography. The purity of antibodies was higher than 90%. The titers of antibodies were more than 1:6000. Western blot and immunohistochemistry assay showed that the specific antibody can combine with endogenous P53 protein in the tumor celllines and determine the expression of P53 in tumor tis-sue. Conclusion:Three strains of monoclonal antibodies with high af inity to P53 were successful y established, which can be used for detecting the expression of P53 in tumor cells or tissue.展开更多
Advanced oxidation processes(AOPs) have been applied to address multiple environmental concerns including antibiotic resistance genes(ARGs). ARGs have shown an increasing threat to human health,and they are either har...Advanced oxidation processes(AOPs) have been applied to address multiple environmental concerns including antibiotic resistance genes(ARGs). ARGs have shown an increasing threat to human health,and they are either harbored by antibiotic-resistant bacteria(ARB) or free in the environment.However, the control of ARGs has been substantially limited by their low concentration and the limited knowledge about their interfacial behavior. Herein, a novel AOP catalyst, Ag/TiO_(2)/graphene oxide(GO),combined with a polyvinylidene fluoride(PVDF) ultrafiltration membrane was designed with a synergistic interfacial adsorption and oxidation function to inactivate ARGs with high efficiency in both model solutions and in secondary wastewater effluent, especially when the residue concentration was low.Further analysis showed that the mineralization of bases and phosphodiesters mainly caused the inactivation of ARGs. Moreover, the interfacial adsorption and oxidation processes of ARGs were studied at the molecular level. The results showed that GO was rich in sp^(2) backbones and functional oxygen groups,which efficiently captured and enriched the ARGs via p-p interactions and hydrogen bonds. Therefore,the photogenerated active oxygen species attack the ARGs by partially overcoming the kinetic problems in this process. The Ag/Ti O2/GO catalyst was further combined with a PVDF membrane to test its potential in wastewater treatment applications. This work offers an efficient method and a corresponding material for the inactivation and mineralization of intra/extracellular ARGs. Moreover, the molecularlevel understanding of ARG behaviors on a solid–liquid interface will inspire further control strategies of ARGs in the future.展开更多
文摘针对低渗透油藏注入性差、洗油效率低,水驱无法有效提高采收率等问题,提出了一种低界面张力小分子驱油剂(LST溶液)提高低渗透油藏采收率新技术,评价了该驱油剂的界面活性、增黏性、乳化性、润湿性及其油藏环境适应性和驱油效果。结果表明,该驱油剂具有良好的界面活性和增黏性。在6788.23 mg/L的矿化水中,质量分数为0.4%时的LST溶液的油水界面张力为0.012 m N/m,且黏度与油藏原油黏度(3.4 m Pa·s)相近。LST溶液具有较好的油水乳化能力,可改善油藏水润湿性。在47.2℃、油水比为1∶1的条件下,LST乳状液的稳定时间为120 min。岩心经LST溶液处理后,水相接触角由57.0°降至12.5°,油相接触角由24.3°增至38.6°。LST溶液具有良好的静态抗吸附性能,经岩心3次吸附后,LST残液与原油间的界面张力仍能达到10^(-2)m N/m数量级,黏度达2.895 m Pa·s,乳状液静置10、120 min的析水率分别为38.6%、73.4%。LST溶液的耐盐性能较好。在矿化度为16570 mg/L的环境下,其油水界面张力低于7×10^(-2)m N/m、黏度为3.06 m Pa·s。LST溶液的驱油效果较好,可有效封堵高渗透孔道,启动低渗透孔道残余油。注入0.4 PV 0.4%LST溶液可使均质岩心(0.05μm^(2))的水驱驱油效率提高11.21百分点,非均质岩心(级差3~10)水驱后的综合采收率提高6.55百分点~19.41百分点。LST溶液可以实现低剂量或低成本有效提高水驱采收率,在低渗透非均质油藏化学驱提高采收率方面具有较好的应用前景。
文摘Stability of Defibrase in various pH buffer solutions was investigated. Enzyme-linked immuno-sorbent assay (ELISA) and coagulating time method were used to assess antigenic stability and coagulating stability, respectively. The change of antigenic activities and coagulating activities of Defibrase in the same buffer solutions (pH 6, 7 and 8, with the exception of pH 3.6) showed similar tendency to decline with the time. Concentrated Defi-brase was relatively stable at neutral pH 6~7, more than 95% of its initial activities (100BUmL-1) was kept after a 10-day storage at 40 oC, whereas in pH 3.6 and pH 9 buffer solutions, diluted Defibrase was very labile. Addition of Triton X-100 or bovine serum albumin could effectively prevent loss of Defibrase by minimizing adsorption of De-fibrase to plastic surface (P<0.005). Concentration of Defibrase could also affect its stability in aqueous solutions.
基金Project supported by the National Natural Science Foundation of China (No. 30671646)the Program for New Century Excellent Talents in University, China (No. NCET-07-0725)the Program for Innovative Research Team in Science and Technology in Fujian Province University, China
文摘The contents of total phenolics and extractable condensed tannins in the leaves, twigs and stem bark of Canarium album were determined. The structural heterogeneity of condensed tannins from stem bark was characterized by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and nuclear magnetic resonance (NMR) analyses The results show the predominance of signals representative of procyanidins and prodelphinidins. In addition, epicatechin and epigallocatechin polymers with galloylated procyanidin or prodelphinidin were also observed. The tannins were screened for their potential antioxidant activities using l,l-diphenyl-2-picrylhydrazyl (DPPH) and ferric reducing/antioxidant power (FRAP) model systems. Tannins extracted from leaves, twigs and stem bark all showed a very good DPPH radical scavenging activity and ferric reducing power.
文摘The. objectives.of this study are to convert at laboratory s.cale agric.ultural residues into activated carbons (AC) with specific properties, to characterize them and to test them in adsorption reactor for tetracycline removal, a common antibiotic. Two new ACs were produced by direct activation with steam from beet pulp (BP-H2O) and peanut hu_lls (PH-H2O) in environmental friendly conditions BP-H2O and PH-H2Opresentcarbon content rangedcarbons with different intrinsic properties.
基金Supported by grants from the National Natural Science Foundation of China(No.30973562)National Basic Research Program of China(No.2010CB933904)
文摘Objective:The aim of this study was to prepare monoclonal antibody against P53, a kind of tumor suppressor protein,and use the antibody initial y in clinical immunoassay. Methods:Monoclonal antibody was prepared and identified via the classic protocol of monoclonal antibody preparation. Identified monoclonal antibodies were purified by af inity chro-matography. Antibody titer was determined by enzyme linked immunosorbent assay (ELISA). The specific binding activity of antibody was detected by Western blotting and immunohistochemistry. Results:Three strains of monoclonal antibodies named 1P15, 2P37 and 3P40 were obtained and purified by af inity chromatography. The purity of antibodies was higher than 90%. The titers of antibodies were more than 1:6000. Western blot and immunohistochemistry assay showed that the specific antibody can combine with endogenous P53 protein in the tumor celllines and determine the expression of P53 in tumor tis-sue. Conclusion:Three strains of monoclonal antibodies with high af inity to P53 were successful y established, which can be used for detecting the expression of P53 in tumor cells or tissue.
基金supported by the National Natural Science Foundation of China (21722702 and 21872102)Tianjin Municipal Science and Technology Bureau (18YFZCSF00730, 18YFZCSF00770, 18ZXSZSF00230 and 19YFZCSF00740)。
文摘Advanced oxidation processes(AOPs) have been applied to address multiple environmental concerns including antibiotic resistance genes(ARGs). ARGs have shown an increasing threat to human health,and they are either harbored by antibiotic-resistant bacteria(ARB) or free in the environment.However, the control of ARGs has been substantially limited by their low concentration and the limited knowledge about their interfacial behavior. Herein, a novel AOP catalyst, Ag/TiO_(2)/graphene oxide(GO),combined with a polyvinylidene fluoride(PVDF) ultrafiltration membrane was designed with a synergistic interfacial adsorption and oxidation function to inactivate ARGs with high efficiency in both model solutions and in secondary wastewater effluent, especially when the residue concentration was low.Further analysis showed that the mineralization of bases and phosphodiesters mainly caused the inactivation of ARGs. Moreover, the interfacial adsorption and oxidation processes of ARGs were studied at the molecular level. The results showed that GO was rich in sp^(2) backbones and functional oxygen groups,which efficiently captured and enriched the ARGs via p-p interactions and hydrogen bonds. Therefore,the photogenerated active oxygen species attack the ARGs by partially overcoming the kinetic problems in this process. The Ag/Ti O2/GO catalyst was further combined with a PVDF membrane to test its potential in wastewater treatment applications. This work offers an efficient method and a corresponding material for the inactivation and mineralization of intra/extracellular ARGs. Moreover, the molecularlevel understanding of ARG behaviors on a solid–liquid interface will inspire further control strategies of ARGs in the future.