Limestone powder is still applied as SO2 sorbent in emerging oxygen-fuel circulating fluidized bed boiler, but its carbonation in O2/CO2 flue gas is an unclear problem. For a better understanding of carbonation behavi...Limestone powder is still applied as SO2 sorbent in emerging oxygen-fuel circulating fluidized bed boiler, but its carbonation in O2/CO2 flue gas is an unclear problem. For a better understanding of carbonation behaviors, the tube furnace heating system was built for simulating circulating fluidized bed boiler flue gas by regulating the supply of O, CO2, N2, SO2 and H2O, and Carbonation reaction was tested. Thermal gravimetric analysis and scanning electron microscopy were used. It was found that carbonation is closely related to temperature, CO2 concentration, impurities, water vapor, and cycle times;high temperature can promote carbonation process;high concentration of CO2 can inhibit the chemical reaction stage speed of carbonation process, but it has little effect on the final conversion rate;water vapor can increase the final conversion rate of carbonation;the cycle times will reduce the activity of carbonation. The presence of carbonation turns the traditional boiler flue gas indirect desulfurization model into indirect desulfurization mechanism which does not have a negative impact on SO2 removal efficiency.展开更多
[Objectives] To explore the protective effect and possible mechanisms of the coenzyme Q10( CoQ 10) on the human umbilical vein endothelial cell( HUVEC) injury induced by the oxidized low-density lipoprotein( ox-LDL). ...[Objectives] To explore the protective effect and possible mechanisms of the coenzyme Q10( CoQ 10) on the human umbilical vein endothelial cell( HUVEC) injury induced by the oxidized low-density lipoprotein( ox-LDL). [Methods]With the human umbilical vein endothelial cells( HUVECs) cultured in vitro as the test target,the HUVECs were randomly divided into 5 groups: normal control group; model group; low concentration CoQ10 group( 12. 5); medium concentration CoQ10 group( 25); high concentration CoQ10 group( 50). The CCK-8 method was used to test the cell viability,and the drug concentration was screened in 60 μM of CoQ 10 toxic concentration; the total protein was extracted and Western blot was used to detect the protein expression of c-fos,c-jun and PON2; the RT-PCR method was used for determination of the content of c-fos,c-jun and PON2 mRNA. [Results]Compared with the normal group,the cell viability was significantly reduced in the 35 μg/m L high ox-LDL model group,and the cell injury was induced; compared with model group,after 12 h pre-protection,12. 5 μM,25 μM,50 μM CoQ10 could all significantly improve the survival of injured cells( P < 0. 05); compared with the normal group;the protein and mRNA levels of c-fos,c-jun,PON2 in the model group all declined; compared with the model group,the protein level and mRNA expression of c-fos,c-jun,PON2 in different CoQ10 groups increased to varying degrees( P < 0. 05). [Conclusions] CoQ 10 could reduce the HUVEC injury induced by high ox-LDL,and possible mechanism was achieved by upregulating the expression of AP-1 and PON2.展开更多
The chemical composition of acid rain and its impact on lake water chemistry in Chongqing,China,from 2000 to 2020 were studied in this study.The regional acid rain intensity is affected jointly by the acid gas emissio...The chemical composition of acid rain and its impact on lake water chemistry in Chongqing,China,from 2000 to 2020 were studied in this study.The regional acid rain intensity is affected jointly by the acid gas emissions and the neutralization of alkaline substances.The pH of precipitation experienced three stages of fluctuating decline,continuous improvement,and a slight correction.Precipitation pH showed inflection points in 2010,mainly due to the total control actions of SO_(2)and NO_(x)implemented in 2011.The total ion concentrations in rural areas and urban areas were 489.08μeq/L and 618.57μeq/L,respectively.The top four ions were SO_(4)^(2-),Ca^(2+),NH_(4)^(+)and NO_(3)^(-),which accounted for more than 90%of the total ion concentration,indicating the anthropogenic effects.Before 2010,SO_(4)^(2-)fluctuated greatly while NO_(3)^(-)continued to rise;however,after 2010,both SO_(4)^(2-)and NO_(3)^(-)began to decline rapidly,with the rates of-12.03μeq/(L·year)and-4.11μeq/(L·year).Because the decline rate of SO_(4)^(2-)was 2.91 times that of NO_(3)^(-),the regional acid rain has changed from sulfuric acid rain to mixed sulfuric and nitric acid rain.The lake water is weakly acidic,with an average pH of 5.86,and the acidification frequency is 30.00%.Acidification of lake water is jointly affected by acid deposition and acid neutralization capacity of lake water.Acid deposition has a profound impact on water acidification,and nitrogen(N)deposition,especially reduced N deposition,should be the focus of future research.展开更多
Lake Caohai has experienced extensive Microcystis blooms in recent years,and to improve its water quality,the local government carried out a series of water control measures.To better understand the dynamics of both p...Lake Caohai has experienced extensive Microcystis blooms in recent years,and to improve its water quality,the local government carried out a series of water control measures.To better understand the dynamics of both pelagic and benthic Microcystis and their characteristics in Lake Caohai,we conducted a 1-year investigation from December 2015to December 2016 to gain a seasonal outlook on the distribution and dynamics of cell abundance,colony size and intracellular microcystins(MCs)of Microcystis.The results indicated that the Microcystis bloom occupied primarily the northeastern region and then moved gradually from lakeshore to lake center.The perennial southwesterly winds and the water inflow from northeast to southwest in Lake Caohai determined the spatiotemporal distribution of pelagic Microcystis.Benthic Microcystis was mainly distributed in the northeastern region in summer,occupied the lake center in autumn and then occupied the southeastern region in winter,determined by the sedimentation of pelagic Microcystis and the death of benthic Microcystis.Small colonies(20-60μm)overwintered more easily in both water column and sediment.The concentrations of intracellular toxin of benthic Microcystis were observed to be significantly higher than those of pelagic Microcystis.This might be because Microcystis synthesized large amount of MCs to acclimate to an unfavorable benthic environment.This knowledge on the dynamics of Microcystis expands our understanding of mechanisms underpinning the formation of Microcystis blooms.展开更多
Cryogel dressings with good absorption ability and photothermal antibacterial properties for preventing wound infections and treating infected wounds have attracted widespread attention.In this work,a series of cryoge...Cryogel dressings with good absorption ability and photothermal antibacterial properties for preventing wound infections and treating infected wounds have attracted widespread attention.In this work,a series of cryogels with macroporous structure,antioxidant and photothermal properties were prepared based on adipic dihydrazide modified hyaluronic acid(HA-ADH),and dopamine(DA).The antioxidant properties,hemostatic properties,near infrared(NIR)assisted photothermal antibacterial ability provided by polydopamine,recyclable compression mechanical properties,and cytocompatibility were tested.The results demonstrated that the HA-ADH/DA cryogels have stable mechanical properties,great antibacterial properties against E.coli(EC)and methicillin-resistant S.aureus(MRSA).The high swelling ratio due to the high water retention of HA equipped the cryogels with the capability of absorbing exuded blood and excessive tissue fluid in the infected full-thickness skin defect model of mouse.The cryogels demonstrated good cytocompatibility and antioxidant performance through cell tests and 1,1-diphenyl-2-methylbenzohydrazino(DPPH)scavenging efficiency test.The cryogels showed enhanced blood-clotting index(BCI)and better hemostatic ability in the mouse liver trauma model and the rat deep noncompressible liver defect model compared with gauze and gelatin sponge.Furthermore,compared with commercial TegadermTMdressing in vivo,the HA-ADH/DA cryogels could greatly promote infected skin wound healing in a full-thickness infected skin defect wound model.In summary,the macroporous HAADH/DA cryogels with good antioxidant,high swelling ratio,photothermal antibacterial property,and biocompatibility are a promising hemostatic material and wound healing dressing.展开更多
文摘Limestone powder is still applied as SO2 sorbent in emerging oxygen-fuel circulating fluidized bed boiler, but its carbonation in O2/CO2 flue gas is an unclear problem. For a better understanding of carbonation behaviors, the tube furnace heating system was built for simulating circulating fluidized bed boiler flue gas by regulating the supply of O, CO2, N2, SO2 and H2O, and Carbonation reaction was tested. Thermal gravimetric analysis and scanning electron microscopy were used. It was found that carbonation is closely related to temperature, CO2 concentration, impurities, water vapor, and cycle times;high temperature can promote carbonation process;high concentration of CO2 can inhibit the chemical reaction stage speed of carbonation process, but it has little effect on the final conversion rate;water vapor can increase the final conversion rate of carbonation;the cycle times will reduce the activity of carbonation. The presence of carbonation turns the traditional boiler flue gas indirect desulfurization model into indirect desulfurization mechanism which does not have a negative impact on SO2 removal efficiency.
基金Supported by Project of National Natural Science Foundation(81274126)
文摘[Objectives] To explore the protective effect and possible mechanisms of the coenzyme Q10( CoQ 10) on the human umbilical vein endothelial cell( HUVEC) injury induced by the oxidized low-density lipoprotein( ox-LDL). [Methods]With the human umbilical vein endothelial cells( HUVECs) cultured in vitro as the test target,the HUVECs were randomly divided into 5 groups: normal control group; model group; low concentration CoQ10 group( 12. 5); medium concentration CoQ10 group( 25); high concentration CoQ10 group( 50). The CCK-8 method was used to test the cell viability,and the drug concentration was screened in 60 μM of CoQ 10 toxic concentration; the total protein was extracted and Western blot was used to detect the protein expression of c-fos,c-jun and PON2; the RT-PCR method was used for determination of the content of c-fos,c-jun and PON2 mRNA. [Results]Compared with the normal group,the cell viability was significantly reduced in the 35 μg/m L high ox-LDL model group,and the cell injury was induced; compared with model group,after 12 h pre-protection,12. 5 μM,25 μM,50 μM CoQ10 could all significantly improve the survival of injured cells( P < 0. 05); compared with the normal group;the protein and mRNA levels of c-fos,c-jun,PON2 in the model group all declined; compared with the model group,the protein level and mRNA expression of c-fos,c-jun,PON2 in different CoQ10 groups increased to varying degrees( P < 0. 05). [Conclusions] CoQ 10 could reduce the HUVEC injury induced by high ox-LDL,and possible mechanism was achieved by upregulating the expression of AP-1 and PON2.
基金supported by the Chongqing Science and Technology Commission Project(No.CSTB2022NSCQ-MSX0818)。
文摘The chemical composition of acid rain and its impact on lake water chemistry in Chongqing,China,from 2000 to 2020 were studied in this study.The regional acid rain intensity is affected jointly by the acid gas emissions and the neutralization of alkaline substances.The pH of precipitation experienced three stages of fluctuating decline,continuous improvement,and a slight correction.Precipitation pH showed inflection points in 2010,mainly due to the total control actions of SO_(2)and NO_(x)implemented in 2011.The total ion concentrations in rural areas and urban areas were 489.08μeq/L and 618.57μeq/L,respectively.The top four ions were SO_(4)^(2-),Ca^(2+),NH_(4)^(+)and NO_(3)^(-),which accounted for more than 90%of the total ion concentration,indicating the anthropogenic effects.Before 2010,SO_(4)^(2-)fluctuated greatly while NO_(3)^(-)continued to rise;however,after 2010,both SO_(4)^(2-)and NO_(3)^(-)began to decline rapidly,with the rates of-12.03μeq/(L·year)and-4.11μeq/(L·year).Because the decline rate of SO_(4)^(2-)was 2.91 times that of NO_(3)^(-),the regional acid rain has changed from sulfuric acid rain to mixed sulfuric and nitric acid rain.The lake water is weakly acidic,with an average pH of 5.86,and the acidification frequency is 30.00%.Acidification of lake water is jointly affected by acid deposition and acid neutralization capacity of lake water.Acid deposition has a profound impact on water acidification,and nitrogen(N)deposition,especially reduced N deposition,should be the focus of future research.
基金supported by the National Natural Science Foundation of China (Nos. 31670465, 31800390 and 31460130)the Joint NSFC-ISF Research Program+1 种基金jointly funded by the National Natural Science Foundation of Chinathe Israel Science Foundation (No, 41561144008)
文摘Lake Caohai has experienced extensive Microcystis blooms in recent years,and to improve its water quality,the local government carried out a series of water control measures.To better understand the dynamics of both pelagic and benthic Microcystis and their characteristics in Lake Caohai,we conducted a 1-year investigation from December 2015to December 2016 to gain a seasonal outlook on the distribution and dynamics of cell abundance,colony size and intracellular microcystins(MCs)of Microcystis.The results indicated that the Microcystis bloom occupied primarily the northeastern region and then moved gradually from lakeshore to lake center.The perennial southwesterly winds and the water inflow from northeast to southwest in Lake Caohai determined the spatiotemporal distribution of pelagic Microcystis.Benthic Microcystis was mainly distributed in the northeastern region in summer,occupied the lake center in autumn and then occupied the southeastern region in winter,determined by the sedimentation of pelagic Microcystis and the death of benthic Microcystis.Small colonies(20-60μm)overwintered more easily in both water column and sediment.The concentrations of intracellular toxin of benthic Microcystis were observed to be significantly higher than those of pelagic Microcystis.This might be because Microcystis synthesized large amount of MCs to acclimate to an unfavorable benthic environment.This knowledge on the dynamics of Microcystis expands our understanding of mechanisms underpinning the formation of Microcystis blooms.
基金the National Natural Science Foundation of China(No.51973172)the Natural Science Foundation of Shaanxi Province(Nos.2020JC-03 and 2019TD-020)+3 种基金State Key Laboratory for Mechanical Behavior of Materialsthe Fundamental Research Funds for the Central Universitiesthe World-Class Universities(Disciplines)and the Characteristic Development Guidance Funds for the Central UniversitiesOpening Project of Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research,College of Stomatology,Xi’an Jiaotong University(No.2019LHM-KFKT008)。
文摘Cryogel dressings with good absorption ability and photothermal antibacterial properties for preventing wound infections and treating infected wounds have attracted widespread attention.In this work,a series of cryogels with macroporous structure,antioxidant and photothermal properties were prepared based on adipic dihydrazide modified hyaluronic acid(HA-ADH),and dopamine(DA).The antioxidant properties,hemostatic properties,near infrared(NIR)assisted photothermal antibacterial ability provided by polydopamine,recyclable compression mechanical properties,and cytocompatibility were tested.The results demonstrated that the HA-ADH/DA cryogels have stable mechanical properties,great antibacterial properties against E.coli(EC)and methicillin-resistant S.aureus(MRSA).The high swelling ratio due to the high water retention of HA equipped the cryogels with the capability of absorbing exuded blood and excessive tissue fluid in the infected full-thickness skin defect model of mouse.The cryogels demonstrated good cytocompatibility and antioxidant performance through cell tests and 1,1-diphenyl-2-methylbenzohydrazino(DPPH)scavenging efficiency test.The cryogels showed enhanced blood-clotting index(BCI)and better hemostatic ability in the mouse liver trauma model and the rat deep noncompressible liver defect model compared with gauze and gelatin sponge.Furthermore,compared with commercial TegadermTMdressing in vivo,the HA-ADH/DA cryogels could greatly promote infected skin wound healing in a full-thickness infected skin defect wound model.In summary,the macroporous HAADH/DA cryogels with good antioxidant,high swelling ratio,photothermal antibacterial property,and biocompatibility are a promising hemostatic material and wound healing dressing.