The BST oilfield in the northwestern Taklamakan Desert is a fractured carbonate reservoir,but issues of water breakthrough are becoming increasingly severe with the development of water flooding.Unfortunately,the high...The BST oilfield in the northwestern Taklamakan Desert is a fractured carbonate reservoir,but issues of water breakthrough are becoming increasingly severe with the development of water flooding.Unfortunately,the high-temperature and high-salt conditions(130°C,71695 mg/L)of the BST oilfield pose challenges for the development of plugging agents.In this study,the effects of 2-acrylamido-2-methylpropane sulfonic acid(AMPS)content on AM/AMPS copolymers and gels were studied through viscosity measurements,nuclear magnetic resonance(NMR),and cryo-scanning electron microscope(Cryo-SEM).Moreover,the AMPS stabilization mechanism of the polymers and gels was explained.Heatresistant and salt-tolerant gel systems were developed,and their gelation properties,thermal stability,injection capacity,and plugging ability were evaluated.Experimental results showed inconsistencies between the effects of AMPS content on the polymers and gels.For the polymers,the thermal stability increased with increased AMPS content in the polymer.However,excessive AMPS content resulted in poor gelation and low strength.The developed gel systems with S30 polymer(AMPS content is approximately 26%)exhibited excellent thermal stability,controllable gelation time,good injection capacity,and plugging ability.The field application results indicated that most production wells had a positive response,with reduced water-cut and increased daily oil production.展开更多
The terpolymer of itaconic acid, acrylamide and 2-acrylamido-2-methyl-1-propane sulfonic acid was synthesized through the free-radical polymerization. The IR spectra confirmed that there was no olefinic band, while th...The terpolymer of itaconic acid, acrylamide and 2-acrylamido-2-methyl-1-propane sulfonic acid was synthesized through the free-radical polymerization. The IR spectra confirmed that there was no olefinic band, while the TGA results revealed that the terpolymer was of high thermal stability.展开更多
OBJECTIVE Propane-2-sulfonic acid octadec-9-enyl-amide(N15),an analogue of oleoylethanolamide(OEA),is a novel PPARα/γdual agonist.Our previous studies verified the positive effects of OEA on the acute and delayed st...OBJECTIVE Propane-2-sulfonic acid octadec-9-enyl-amide(N15),an analogue of oleoylethanolamide(OEA),is a novel PPARα/γdual agonist.Our previous studies verified the positive effects of OEA on the acute and delayed stages of cerebral ischaemia.However,it is not clear whether N15 is effective against ischaemic cerebral injury.In the present study,male Kunming mice were subjected to middle cerebral artery occlusion(MCAO).METHODS To evaluate its preventive effects,N15(50,100 or 200 mg·kg-1,ip)was administered for3 d before ischaemia.To evaluate its therapeutic effects,N15(200 mg·kg-1,ip)was administered 1 h before reperfusion or 0,1,2 or 4 h after reperfusion.Neurological deficit scores,infarct volume and the degree of brain oedema were determined at 24 h after reperfusion.Blood brain barrier(BBB)disruption was evaluated by Evans blue(EB)leakage at 6 h after reperfusion.The activation/inflammatory responses of microglia were detected using immunohistochemistry and Western blotting.RESULTS N15 pretreatment improved neurological dysfunction,reduced infarct volume and alleviated brain oedema in a dose-dependent manner;the most effective dose was 200 mg·kg-1.The therapeutic time window was within 2 h after reperfusion.Moreover,N15was more potent in the treatment of cerebral ischaemia injury than OEA.N15 treatment preserved the BBB integrity and suppressed the activation of microglia.N15 inhibited inflammatory cytokine expression not only in MCAO mice but also in lipopolysaccharide(LPS)-stimulated BV-2microglial cells.Moreover,N15 decreased the phosphorylation levels of NF-κBp65,STAT3,and ERK1/2 both in vivo and in vitro.CONCLUSION Our findings demonstrated that N15 exerts neuroprotective effects and was more potent than OEA.Additionally,the neuroprotective effects of N15 on cerebral ischaemia may be attributed to its anti-inflammatory properties,at least in part,by enhancing PPARα/γdual signalling and inhibiting the activation of the NF-κB,STAT3,and ERK1/2 signalling pathways.These findings suggest that N15 may be a potential therapeutic choice for the prevention and treatment of ischaemic stroke.展开更多
基金Financial support from the Major Scientific and Technological Project of CNPC under grant number ZD2019-183-007Sinopec Northwest Company of China for the financial support(34400007-17-ZC06070095)
文摘The BST oilfield in the northwestern Taklamakan Desert is a fractured carbonate reservoir,but issues of water breakthrough are becoming increasingly severe with the development of water flooding.Unfortunately,the high-temperature and high-salt conditions(130°C,71695 mg/L)of the BST oilfield pose challenges for the development of plugging agents.In this study,the effects of 2-acrylamido-2-methylpropane sulfonic acid(AMPS)content on AM/AMPS copolymers and gels were studied through viscosity measurements,nuclear magnetic resonance(NMR),and cryo-scanning electron microscope(Cryo-SEM).Moreover,the AMPS stabilization mechanism of the polymers and gels was explained.Heatresistant and salt-tolerant gel systems were developed,and their gelation properties,thermal stability,injection capacity,and plugging ability were evaluated.Experimental results showed inconsistencies between the effects of AMPS content on the polymers and gels.For the polymers,the thermal stability increased with increased AMPS content in the polymer.However,excessive AMPS content resulted in poor gelation and low strength.The developed gel systems with S30 polymer(AMPS content is approximately 26%)exhibited excellent thermal stability,controllable gelation time,good injection capacity,and plugging ability.The field application results indicated that most production wells had a positive response,with reduced water-cut and increased daily oil production.
文摘The terpolymer of itaconic acid, acrylamide and 2-acrylamido-2-methyl-1-propane sulfonic acid was synthesized through the free-radical polymerization. The IR spectra confirmed that there was no olefinic band, while the TGA results revealed that the terpolymer was of high thermal stability.
基金The project supported by National Natural Sciences Foundation of China(81373407)the Natural Science Foundation of Fujian Province(2016D018)
文摘OBJECTIVE Propane-2-sulfonic acid octadec-9-enyl-amide(N15),an analogue of oleoylethanolamide(OEA),is a novel PPARα/γdual agonist.Our previous studies verified the positive effects of OEA on the acute and delayed stages of cerebral ischaemia.However,it is not clear whether N15 is effective against ischaemic cerebral injury.In the present study,male Kunming mice were subjected to middle cerebral artery occlusion(MCAO).METHODS To evaluate its preventive effects,N15(50,100 or 200 mg·kg-1,ip)was administered for3 d before ischaemia.To evaluate its therapeutic effects,N15(200 mg·kg-1,ip)was administered 1 h before reperfusion or 0,1,2 or 4 h after reperfusion.Neurological deficit scores,infarct volume and the degree of brain oedema were determined at 24 h after reperfusion.Blood brain barrier(BBB)disruption was evaluated by Evans blue(EB)leakage at 6 h after reperfusion.The activation/inflammatory responses of microglia were detected using immunohistochemistry and Western blotting.RESULTS N15 pretreatment improved neurological dysfunction,reduced infarct volume and alleviated brain oedema in a dose-dependent manner;the most effective dose was 200 mg·kg-1.The therapeutic time window was within 2 h after reperfusion.Moreover,N15was more potent in the treatment of cerebral ischaemia injury than OEA.N15 treatment preserved the BBB integrity and suppressed the activation of microglia.N15 inhibited inflammatory cytokine expression not only in MCAO mice but also in lipopolysaccharide(LPS)-stimulated BV-2microglial cells.Moreover,N15 decreased the phosphorylation levels of NF-κBp65,STAT3,and ERK1/2 both in vivo and in vitro.CONCLUSION Our findings demonstrated that N15 exerts neuroprotective effects and was more potent than OEA.Additionally,the neuroprotective effects of N15 on cerebral ischaemia may be attributed to its anti-inflammatory properties,at least in part,by enhancing PPARα/γdual signalling and inhibiting the activation of the NF-κB,STAT3,and ERK1/2 signalling pathways.These findings suggest that N15 may be a potential therapeutic choice for the prevention and treatment of ischaemic stroke.
