Sulfate transporters(SULTRs)facilitate sulfate uptake and transport in plants.In plants,SULTRs can be classified into four distinct functional groups,among which SULTR3 members are the least characterized,and their fu...Sulfate transporters(SULTRs)facilitate sulfate uptake and transport in plants.In plants,SULTRs can be classified into four distinct functional groups,among which SULTR3 members are the least characterized,and their functions have not yet been confirmed,especially for SULTR3 in rice.In this study,we analyzed the expression patterns,subcellular localization,and inorganic phosphate(Pi)transporter activity of SULTR3 proteins in yeast.Except for OsSULTR3.4,which localized to the plasma membrane,other OsSULTR3 members were localized to the endoplasmic reticulum(ER)membrane in rice protoplast cells.展开更多
Chondroitin sulfate(CS)is one of the main bioactive compounds in animal cartilage.In this study,the antiinflammatory activity of sturgeon-derived chondroitin sulfate(SCS)was evaluated in the dextran sulfate sodium(DSS...Chondroitin sulfate(CS)is one of the main bioactive compounds in animal cartilage.In this study,the antiinflammatory activity of sturgeon-derived chondroitin sulfate(SCS)was evaluated in the dextran sulfate sodium(DSS)-induced BALB/c mice model.Orally administration of SCS significantly alleviated the DSSinduced colitis symptoms,including the reduction of crypt depth,inhibition of the abnormal crypt foci formation,down-regulation of the proinflammatory biomarkers(NO,interleukin(IL)-6,IL-1βand tumor necrosis factor-α)and up-regulation of the anti-inflammatory biomarkers(IL-10 and IL-4).The gut microbiota analysis revealed that SCS alters the intestinal microbiota composition in colitis mice,especially the increase of the relative abundance of Ruminococcaceae and Lachnospiraceae.This alternation further induced primary bile acids convert into secondary bile acids.With SCS administration,the levels of deoxycholic acid(DCA)and litho cholic acid(LCA)were increased by 1.5-and 2.5-fold,respectively.The stimulated secretion of DCA and LCA showed further activation of the NF-κB signaling pathway,thereby suppressing the inflammatory response and attenuating inflammatory bowel disease(IBD)in mice.This study provided a valuable strategy for colitis prevention and treatment with sturgeon cartilage by-products.展开更多
Sea cucumber derived sulfated sterols significantly ameliorated insulin resistance and decreased lipid accumulation compared to plant sterols.Interestingly,our recent study found that intervention with sea cucumber su...Sea cucumber derived sulfated sterols significantly ameliorated insulin resistance and decreased lipid accumulation compared to plant sterols.Interestingly,our recent study found that intervention with sea cucumber sulfated sterols could significantly increase blood glucose levels of healthy mice in the presence of glucose,while cholesterol sulfate,as one of sulfated sterols,did not have the same effect.However,the exact mechanism of sulfated sterols on glucose metabolism is still unknown.In the present study,we investigated the potential mechanism by which sulfated sterols influenced blood glucose homeostasis in healthy mice.Results showed that intervention with sea cucumber sulfated sterols did not affect the levels of hormones related to glucose metabolism,while led to a significant decrease in the synthesis of liver glycogen and muscle glycogen.Besides,the expression of proteins associated with the promotion of gluconeogenesis dramatically increased in the mice intervened with sea cucumber sulfated sterols.These findings suggested that sea cucumber sulfated sterols might change blood glucose metabolism in healthy mice by reducing glycogenesis and promoting gluconeogenesis.展开更多
Sulfamethoxazole(SMZ)is a prevalent and recalcitrant micropollutant in water,posing a significant threat to both aquatic organisms and human health.Therefore,investigating the removal of SMZ is of critical importance....Sulfamethoxazole(SMZ)is a prevalent and recalcitrant micropollutant in water,posing a significant threat to both aquatic organisms and human health.Therefore,investigating the removal of SMZ is of critical importance.In order to investigate the effect of rare earth metal doping on the performance of activated persulfate oxidative degradation of SMZ,BiFeO_(3)with different Ce doping amounts was successfully prepared by a hydrothermal method.Then,it was characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),scanning transmission electro n microscopy(STEM)and Brunauer-Emmett-Teller(BET)method.The performance of porous Ce/BiFeO_(3)in the catalytic activation of persulfate(PMS)for the degradation of SMZ in water was investigated using SMZ solution as a simulated wastewater.The impact of Ce doping rate,catalyst dosage,temperature variations,common anions,natural organic matter,and PMS concentration on SMZ removal was systematically evaluated.The characterization results show that the octahedral rhombic structure of Ce can be observed on the surface of this doped catalyst,and Ce doping does not change the crystalline shape of Ce/BiFeO_(3).The specific surface area of the doped catalyst increases,accompanied by an enlargement of pore size,thereby enhancing the catalyst's adsorption capacity and resistance to contamination by SMZ.Under the optimal conditions of 25℃,SMZ concentration of 20 mg/L,0.8 g/L PMS and 0.3 g/L 0.05Ce/BiFeO_(3)catalyst,the removal rate of SMZ reaches approximately 95%within35 min of reaction time.Even after five cycles of reuse,the degradation rate of SMZ remains above 88%,demonstrating the catalyst's good stability and reusability.Bursting experiments show that SO_(4)^(·-),·OH,1O_(2)and O_(2)^(·-)are involved in the catalytic degradation process,with 1O_(2)playing a dominant role.展开更多
The progressive failure characteristics of geomaterial are a remarkable and challenging topic in geotechnical engineering.To study the effect of salt content and temperature on the progressive failure characteristics ...The progressive failure characteristics of geomaterial are a remarkable and challenging topic in geotechnical engineering.To study the effect of salt content and temperature on the progressive failure characteristics of frozen sodium sulfate saline sandy soil,a series of uniaxial compression tests were performed by integrating digital image correlation(DIC)technology into the testing apparatus.The evolution law of the uniaxial compression strength(UCS),the failure strain,and the formation of the shear band of the frozen sodium sulfate saline sandy soil were analyzed.The test results show that within the scope of this study,with the increase of salt content,both the UCS and the shear band angle initially decrease with increasing salt content before showing an increase.In contrast,the failure strain and the width of the shear band exhibit an initial increase followed by a decrease in the samples.In addition,to investigate the brittle failure characteristics of frozen sodium sulfate saline sandy soil,two classic brittleness evaluation methods were employed to quantitatively assess the brittleness level for the soil samples.The findings suggest that the failure characteristics under all test conditions in this study belong to the transition stage between brittle and ductile,indicating that frozen sodium sulfate saline sandy soil exhibits certain brittle behavior under uniaxial compression conditions,and the brittleness index basically decreases and then increases with the rise in salt content.展开更多
The paper presents experimental investigation results of crack pattern change in cement pastes caused by external sulfate attack(ESA).To visualize the formation and development of cracks in cement pastes under ESA,an ...The paper presents experimental investigation results of crack pattern change in cement pastes caused by external sulfate attack(ESA).To visualize the formation and development of cracks in cement pastes under ESA,an X-ray computed tomography(X-ray CT)was used,i e,the tomography system of Zeiss Xradia 510 versa.The results indicate that X-CT can monitor the development process and distribution characteristics of the internal cracks of cement pastes under ESA with attack time.In addition,the C3A content in the cement significantly affects the damage mode of cement paste specimens during sulfate erosion.The damage of ordinary Portland cement(OPC)pastes subjected to sulfate attack with high C3A content are severe,while the damage of sulfate resistant Portland cement(SRPC)pastes is much smaller than that of OPC pastes.Furthermore,a quadratic function describes the correlation between the crack volume fraction and development depth for two cement pastes immermed in sulfate solution.展开更多
A zinc sulfate open framework matrix,[Zn(SO_4)(DMSO)](1),was synthesized by solvothermal evaporationusing dimethyl sulfoxide(DMSO)as the solvent.A compositeP@1,which exhibits fluorescence and room tempera-ture phospho...A zinc sulfate open framework matrix,[Zn(SO_4)(DMSO)](1),was synthesized by solvothermal evaporationusing dimethyl sulfoxide(DMSO)as the solvent.A compositeP@1,which exhibits fluorescence and room tempera-ture phosphorescence(RTP)properties,was prepared by doping 2,6-naphthalic acid(P)into matrix1at a low con-centration.P@1emitted a green RTP that was visible to the naked eye and lasted for approximately 2 s.P@1exhib-ited selective phosphorescence enhancement response towards Pb^(2+),with a detection limit of 2.52μmol·L^(-1).Themain detection mechanism is the Pb—O coordination-induced phosphorescence enhancement in the system.Inter-estingly,P@1also functioned as a dual-channel probe for the rapid detection of Fe^(3+)ions through fluorescencequenching with a detection limit of 0.038μmol·L^(-1).The recognition mechanism may be attributed to the competi-tive energy absorption betweenP@1and Fe^(3+)ions.CCDC:2388502,1.展开更多
Chondroitin sulfate(CS) B and T are rare subtypes of CS,which are scare in nature.There are also limited synthetic methods to prepare them.Here we report an ingenious semisynthetic approach to prepare a library of dis...Chondroitin sulfate(CS) B and T are rare subtypes of CS,which are scare in nature.There are also limited synthetic methods to prepare them.Here we report an ingenious semisynthetic approach to prepare a library of disaccharides,tetrasaccharides and hexasaccharides of CS-B and CS-T based on the acid or enzymatic degradation of natural CS polysaccharide in 9 or 10 steps.Our approach is the shortest synthetic route toward size-defined CS-B and CS-T oligosaccharides reported to date.In addition,a regioselective protection method of hydroxyls is highlighted,which has achieved the regioselective protection of 4 hydroxyl groups among 7 equatorial hydroxyl groups.By preparing size-defined rare CS oligosaccharides from commercially available natural CS polysaccharides,this strategy has the potential to meet the need of rare natural oligosaccharides.展开更多
Objective:To assess the protective effects of Panax ginseng(PG)against copper sulfate(CuSO_(4))-induced kidney toxicity in rats.Methods:The rats were randomly allocated into four groups:control,CuSO_(4),PG,and PG+CuSO...Objective:To assess the protective effects of Panax ginseng(PG)against copper sulfate(CuSO_(4))-induced kidney toxicity in rats.Methods:The rats were randomly allocated into four groups:control,CuSO_(4),PG,and PG+CuSO_(4).The experiment continued for 14 days,during which CuSO_(4) was provided at a dosage of 100 mg/kg body weight per day and PG at 300 mg/kg body weight by oral gavage per day.Upon completion of the experiment,kidney sections were used for histological and histomorphometric analyses.The histochemical method was applied to ascertain the density of the glomerular mesangial matrix.The expressions of vascular endothelial growth factor(VEGF)and caspase-3 were examined using immunohistochemistry.The levels of malondialdehyde and glutathione,along with the activity of superoxide dismutase and catalase in the kidney,were measured.Results:PG treatment exhibited a marked protective effect against CuSO_(4)-induced renal damage,as evidenced by improved histopathological lesions,significantly reduced glomerular mesangial matrix density,VEGF in distal tubules,caspase-3 expression,and malondialdehyde levels in renal tissue,as well as enhanced superoxide dismutase and catalase activities.Conclusions:PG treatment ameliorates CuSO_(4)-induced kidney injury in rats.Further studies are warranted to verify its efficacy and elucidate the underlying mechanism of its nephroprotective action.展开更多
BACKGROUND Nikethamide,a respiratory stimulant,is used to treat hypoxemia caused by coronavirus disease 2019(COVID-19),but it carries a risk of convulsions.Magnesium sulfate(MgSO_(4)),a seizure inhibitor,might serve a...BACKGROUND Nikethamide,a respiratory stimulant,is used to treat hypoxemia caused by coronavirus disease 2019(COVID-19),but it carries a risk of convulsions.Magnesium sulfate(MgSO_(4)),a seizure inhibitor,might serve as a rescue agent against nikethamide-induced seizures.AIM To investigate the therapeutic effect of MgSO_(4)on nikethamide-induced seizures in COVID-19 patients through animal experiments,providing experimental support for the clinical application of MgSO_(4)in preventing and treating seizures caused by nikethamide.METHODS Forty mice were randomly divided into four groups:(1)Physiological saline;(2)Low-dose MgSO_(4)(50 mg/kg);(3)Medium-dose MgSO_(4)(100 mg/kg);and(4)High-dose MgSO_(4)(200 mg/kg).After 15 minutes of intraperitoneal injection of different doses of MgSO_(4)or an equal volume of physiological saline,the mice were injected with nikethamide(250 mg/kg).RESULTS Compared to the normal saline group,all doses of MgSO_(4)significantly prolonged the seizure latency and reduced the severity of convulsions.However,they also extended the duration of seizures and correspondingly increased survival time(P<0.05).The incidence of seizures and mortality rate in the MgSO_(4)-treated groups were significantly lower than those in the normal saline group(P<0.05).CONCLUSION MgSO_(4)can prevent and treat seizures caused by nikethamide in mice.This finding has implications for the application of MgSO_(4)in treating and preventing seizures caused by nikethamide in COVID-19 treatment.展开更多
As an important component of secondary aerosols,sulfate plays a crucial role in regulating atmospheric radiative balance and influencing the secondary formation of ozone(O_(3)).In real atmosphere,atmospheric oxidants ...As an important component of secondary aerosols,sulfate plays a crucial role in regulating atmospheric radiative balance and influencing the secondary formation of ozone(O_(3)).In real atmosphere,atmospheric oxidants NO_(2)and O_(3)can promote the oxidation of SO_(2)to form sulfate(SO_(4)^(2−))through multiphase chemistry that occur at different time scales.Due to the combined impact of meteorology,pollution sources,atmospheric chemistry,etc.,time-scale dependence of SO_(2)-SO_(4)^(2−)conversion makes the impact of NO_(2)/O_(3)on it more complex.In this study,based on long-term time series(2013-2020)of air pollution variables from seven stations in Hong Kong,the Multifractal Detrended Cross-Correlation Analysis(MFDCCA)method has been employed to quantify the cross-correlations between SO_(2)and SO_(4)^(2−)in real atmosphere at different time scales,for examining the time-scale dependence of SO_(2)-SO_(4)^(2−)conversion efficiency.Furthermore,the Pearson correlation analysis has been used to study the influence of NO_(2)/O_(3)on SO_(2)-SO_(4)^(2−)conversion,and the regional and seasonal differences have been analyzed by considering factors such as meteorology,pollution sources,and regional transport.Changes in the main components of secondary aerosols are closely linked with the co-control of regional PM_(2.5)and O_(3).Therefore,the exploration of the impact of co-existing NO_(2)/O_(3)gases on the secondary formation of sulfates in real atmosphere is significant.展开更多
Sulfates are always promising short-wave ultraviolet(UV)nonlinear optical(NLO)candidates,if their birefringence could be greatly improved.Here,in terms of the insufficient birefringence,the unity of heteroleptic tetra...Sulfates are always promising short-wave ultraviolet(UV)nonlinear optical(NLO)candidates,if their birefringence could be greatly improved.Here,in terms of the insufficient birefringence,the unity of heteroleptic tetrahedral groups and triangular ones was proposed and implemented.Thus,a new semiorganic crystal,[C(NH_(2))_(3)]S_(3)O_(6)(G_(2)S_(3)O_(6)),was obtained,which is composed of[S_(3)O_(6)]^(2-)and[C(NH_(2))_(3)]+groups.It exhibits excellent optical properties with a short absorption cutoff edge of 218 nm,a strong NLO response of 1.4×KH_(2)PO_(4),and more especially,a large birefringence of 0.097@546 nm.This birefringence leap makes the G_(2)S_(3)O_(6) crystal achieve a phase-matching behavior under a 532 nm laser.Thus,the synergy of[S_(3)O_(6)]^(2-)and[C(NH_(2))_(3)]~+groups results in excellent optical performances.This finding opens a new horizon for exploring novel UV NLO crystals.展开更多
Objective:To investigate the effect of synbiotic mulberry on kidney injury in a dextran sodium sulfate(DSS)-induced colitis model.Methods:Male Wistar rats were given drinking water containing 4%DSS for 7 days.Subseque...Objective:To investigate the effect of synbiotic mulberry on kidney injury in a dextran sodium sulfate(DSS)-induced colitis model.Methods:Male Wistar rats were given drinking water containing 4%DSS for 7 days.Subsequently,the rats were treated by oral gavage with synbiotic mulberry at 250,500,and 1000 mg/kg,sulfasalazine at 100 mg/kg,or synbiotic at 1000 mg/kg for an additional 7 days while receiving 0.4%DSS in drinking water.The severity of colitis was evaluated based on the disease activity index score.On day 14,plasma was collected,and the kidneys were harvested to evaluate kidney injury parameters and histological changes.In addition,the expression of genes associated with kidney injury was determined by quantitative RT-PCR.Results:Treatment with all doses of synbiotic mulberry significantly lowered the disease activity index score,accompanied by reductions in kidney histopathological changes,malondialdehyde concentration,and plasma cystatin C levels.Kidney fibrosis was also ameliorated by 500 and 1000 mg/kg of synbiotic mulberry.Treatment with 250 and 500 mg/kg of synbiotic mulberry downregulated IL-18 mRNA expression,while KIM-1 mRNA expression was reduced and plasma lipopolysaccharide-binding protein level was restored by 1000 mg/kg of synbiotic mulberry.Conclusions:Synbiotic mulberry ameliorates kidney injury in rats with DSS-induced colitis.It may be further explored as a treatment of kidney injury under colitis conditions.展开更多
Aluminum is the main impurity of the weathered crust elution-deposited rare earth ore(WCED-REO).Efficient leaching of rare earths and low leaching of aluminum are of great importance for the leaching of the WCED-REO.T...Aluminum is the main impurity of the weathered crust elution-deposited rare earth ore(WCED-REO).Efficient leaching of rare earths and low leaching of aluminum are of great importance for the leaching of the WCED-REO.The effects of pH,MgSO_(4) concentration and Al^(3+)concentration of the leaching agent solution on the column leaching behaviors of WCED-REO using magnesium sulfate were investigated.Experimental data show that controlling the MgSO_(4) concentration to 0.15 mol/L,pH of the leaching agent solution to 2,the leaching amount of aluminum from the rare earth ore gradually decreases with the increase of Al^(3+)concentration in the leaching agent solution,indicating that Al^(3+)in the leaching agent solution may act as leaching agent to participate in the ion exchange of RE3+,but the leaching amounts of rare earths change insignificantly as the Al^(3+)concentration is increased.Increasing the MgSO_(4) concentration is beneficial to the leaching of aluminum,and when the Al^(3+)concentration is 0.04 mol/L(Al accumulation),the amount of Al^(3+)leached from the rare earth ore increased gradually with increasing the MgSO_(4) concentration.The pH of the leaching agent solution has a significant influence on the leaching of aluminum in the rare earth ore,and the leaching amount of aluminum from the rare earth ore increases gradually with decreasing the pH.When the Al^(3+)conce ntration is 0.04 mol/L(Al accumulation)and the pH of the leaching agent solution is above 2.0,the aluminum in the leaching agent solution can be back-adsorbed onto the rare earth ore,and the amount of the back-adsorbed Al^(3+)increases with increasing the pH of the leaching agent solution.The injection rate of the leaching agent solution has slight effect on the leaching behavior of rare earths and aluminum.In summary,leaching of Al^(3+)and consumption of MgSO_(4) can be reduced by regulating the accumulation of aluminum,MgSO_(4) concentration and pH.展开更多
Ion-adsorption rare earth ore(IAREO)is a crucial source of mid-heavy rare earths elements(M-HRE).Reverse osmosis technology is a promising technique for the pre-concentration of the leach solution from in-situ leachin...Ion-adsorption rare earth ore(IAREO)is a crucial source of mid-heavy rare earths elements(M-HRE).Reverse osmosis technology is a promising technique for the pre-concentration of the leach solution from in-situ leaching of IAREO.However,calcium sulfate scaling is inevitably formed in sulfate system,causing decreases in the flux and life time of membrane.Herein,to simulate the precipitation behavior of calcium sulfate in the leach solution of IAREO during reverse osmosis,a series of experiments was conducted in binary and quaternary supersaturated calcium sulfate solution systems.Experimental data show that the concentration of Ca^(2+)decreases with the increase of the concentration of Mg^(2+),and in-creases with the increase of the concentration of RE3+in both binary and quaternary systems.Whereas.the influence of Al^(3+)on the concentration of Ca^(2+)is different.This variation of the Ca^(2+)concentration is explained by thermodynamic analysis.The difference of association concentration for Mg^(2+),Al^(3+)and RE^(3+)with SO_(4)^(2-)in binary or quaternary system is the main reason.Finally,the influence and mechanisms of antiscalant on the precipitation behavior of calcium sulfate are discussed.X-ray diffraction(XRD),Zeta potential and scanning electron microscopy(SEM)analyses reveal that polyacrylic acid(PAA)effectively inhibits the crystal growth of calcium sulfate,and the precipitation time of calcium sulfate is prolonged,indicating that PPA is a potential inhibitor for calcium sulfate scaling during the process of reverse osmosis.展开更多
Aqueous-phase reactions between carbonyls and reduced nitrogen compounds play a considerable role in the formation of secondary organic aerosols and brown carbon in the atmosphere.However,the reported reaction rate co...Aqueous-phase reactions between carbonyls and reduced nitrogen compounds play a considerable role in the formation of secondary organic aerosols and brown carbon in the atmosphere.However,the reported reaction rate constants for these reactions have largely been limited to bulk aqueous-phase simulations,which may not accurately represent the real state of atmospheric cloud droplets.We employed an integration of optical tweezers and Raman spectroscopy to manipulate and analyze simulated cloud droplets(size range8000-10,000 nm),comprising a mixture of glyoxal and ammonium sulfate.This approach enabled us to delve into the intricate realm of their reaction kinetics at individual droplet level mimicking cloud droplets.Raman spectroscopy provided high temporal resolution(20 s)measurements of the changes in the amount of nitrogen-containing organics(or NOCs as represented by the C-N bond)within the droplets.The results indicate that the reaction follows first-order kinetics throughout the monitoring over 80-400 min.The average reaction rate constant for the formation of NOCs within the single droplet was determined to be(6.77±0.98)×10^(-5)s^(-1),up to three orders of magnitude higher than those through the bulk aqueous-phase simulations,especially at lower p H levels.Additionally,the reaction rate constant in single droplet increases with increasing p H,consistent with the trend previously reported for the bulk aqueous-phase simulations.The results highlight the difference of the reaction rate constant between bulk aqueous-phase and droplets,which would improve our understanding on the formation and impacts of secondary organic aerosols and brown carbon in atmospheric aqueous phase.展开更多
In order to explore the mechanical properties and microstructure changes of frozen saline silty clay in the Hexi region of Gansu Province,triaxial compression tests and scanning electron microscopy(SEM)analysis experi...In order to explore the mechanical properties and microstructure changes of frozen saline silty clay in the Hexi region of Gansu Province,triaxial compression tests and scanning electron microscopy(SEM)analysis experiment were conducted to explore the effects of moisture content,confining pressure,and temperature on the stress-strain characteristics and failure modes of frozen soil,as well as the changes in the internal microstructure of the sample.The experimental results show that the strength of frozen sulfate saline soil first increases and then decreases with the increase of moisture content,and the maximum strength corresponds to a moisture content of 15%.The changes in confining pressure and strength have the same trend.The lower the temperature,the greater the strength of the sample.During the entire loading process,the specimens undergo a gradual transition from volume shrinkage to volume expansion.Due to the strain harden behavior of the stress-strain curve throughout the entire loading process,the failure mode of the specimens is plastic failure.The internal microstructure of the sample gradually transitions from point-point contact and edge-point contact before shearing to edge-surface contact and edge-edge contact after shearing,and the pore size inside the sample increases after shearing,with a loose arrangement of the particle skeleton.The above research conclusions can lay a certain theoretical foun-dation for the engineering design and construction of sulfate saline soil in cold and arid areas.展开更多
The photochemical conversion of SO_(2) to sulfates on 4-(benzoyl)benzoic acid(4-BBA)was investigated deeply in the presence of anionic and cationic surfactants.The types of surfactants determined their effect behavior...The photochemical conversion of SO_(2) to sulfates on 4-(benzoyl)benzoic acid(4-BBA)was investigated deeply in the presence of anionic and cationic surfactants.The types of surfactants determined their effect behaviors,and cationic surfactants can significantly enhance the SO_(2) oxidation on 4-BBA under irradiation,as shown by larger SO_(2) uptake coefficients and sulfate production.Hydrophilic moieties in cationic surfactants have a greater enhancement effect on the photochemical conversion of SO_(2) to sulfates than the corresponding hydrophobic moieties.Cationic surfactants obviously increased the accumulation of H_(2)O on the surface,which was proved to be the main factor influencing the SO_(2) uptake and the sulfate formation on 4-BBA.SO_(2) lifetime and sulfate formation rate in the mixture system of photosensitive substances with surfactants were evaluated to be 2.25 days and 0.09μg/(m^(3)·h),respectively.展开更多
The engineering diseases caused by seasonal sulfate saline soil in Hexi region of Gansu Province seriously affect the local infrastructure construction and operation maintenance.To address this issue,this study explor...The engineering diseases caused by seasonal sulfate saline soil in Hexi region of Gansu Province seriously affect the local infrastructure construction and operation maintenance.To address this issue,this study explored the thermal mass transfer law,pore fluid phase transition,soil deformation and microstructure of unsaturated sulfate saline soil under the open system.Firstly,based on the theories of porous media mechanics and continuum mechanics,combined with the conservation equations of mass,energy and momentum and considering the phase transition of pore fluid,a multi-field coupled mathematical model of hydro-thermal-salt-gasmechanical for unsaturated sulfate saline soil was established.Secondly,basic unknown variables such as pore water pressure,concentration,temperature,porosity,and displacement were selected to perform numerical simulation analysis on the equation system by“Comsol Multiphysics”finite element method.Finally,a comparative analysis was conducted between the on-site measured data and the numerical simulation results.The results show that the water and salt phase transitions caused by temperature change could lead to soil salt heave and frost heave,alter the pore structure of the soil,and reduce the compactness of the soil,ultimately being reflected in the changes in soil porosity.The influence of external temperature on soil temperature gradually decreases with increasing depth,and the sensitivity of frozen areas to external temperature is much higher than that of unfrozen areas.This study not only enriches the theoretical results of thermal mass transfer law and deformation of unsaturated sulfate saline soil,but also provides practical guidance for the prevention and control of engineering diseases in local sulfate saline soil.展开更多
Intense evaporation in areas with loess-like sulfate saline soils has resulted in significant ecological challenges that include water shortages and soil salinization.Investigating evaporation rate in loess-like sulfa...Intense evaporation in areas with loess-like sulfate saline soils has resulted in significant ecological challenges that include water shortages and soil salinization.Investigating evaporation rate in loess-like sulfate saline soils under varying salt contents carries crucial implications for understanding regional water loss processes,predicting soil salinization advancement,and formulating effective ecological management strategies.Therefore,this study sampled the loess-like sulfate saline soil that is widely distributed in western China as experimental materials and investigated the impact of different initial salt contents(0.00%,0.50%,1.50%,3.00%,and 5.00%)on the evaporation rate,water content,and temperature of soil.The results showed that the evaporation rate decreased with increasing initial salt content.After a salt accumulation layer formed on the soil surface,the water content of the surface soil fluctuated.An increase in the initial salt content resulted in a corresponding increase in the surface temperature.Considering the evaporation characteristics of loess-like sulfate saline soil and the impact of an anomalous increase in surface soil water content on soil surface resistance,this study proposed a modified evaporation model on the basis of Fujimaki's evaporation model of saline soil by introducing a correction coefficientβto modify the soil surface resistance.A comparison of the calculated evaporation rates before and after the modification with the measured evaporation rates revealed a significant improvement in the calculation accuracy of the modified model,indicating that the modified model is capable of more accurately simulating the evaporation rate of sulfate saline soil with different initial salt contents.This paper proposes an effective method for calculating the evaporation rate of loess-like sulfate saline soils,providing a theoretical basis for evaporation research in saline soil.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.32130096 and 32172667)the Central Public-Interest Scientific Institution Basal Research Fund,China(Grant No.Y2022QC14).
文摘Sulfate transporters(SULTRs)facilitate sulfate uptake and transport in plants.In plants,SULTRs can be classified into four distinct functional groups,among which SULTR3 members are the least characterized,and their functions have not yet been confirmed,especially for SULTR3 in rice.In this study,we analyzed the expression patterns,subcellular localization,and inorganic phosphate(Pi)transporter activity of SULTR3 proteins in yeast.Except for OsSULTR3.4,which localized to the plasma membrane,other OsSULTR3 members were localized to the endoplasmic reticulum(ER)membrane in rice protoplast cells.
基金funded by grants from Beijing Fishery Innovation Team Project(BAIC07-2023-13)National Natural Science Foundation of China(32201994)。
文摘Chondroitin sulfate(CS)is one of the main bioactive compounds in animal cartilage.In this study,the antiinflammatory activity of sturgeon-derived chondroitin sulfate(SCS)was evaluated in the dextran sulfate sodium(DSS)-induced BALB/c mice model.Orally administration of SCS significantly alleviated the DSSinduced colitis symptoms,including the reduction of crypt depth,inhibition of the abnormal crypt foci formation,down-regulation of the proinflammatory biomarkers(NO,interleukin(IL)-6,IL-1βand tumor necrosis factor-α)and up-regulation of the anti-inflammatory biomarkers(IL-10 and IL-4).The gut microbiota analysis revealed that SCS alters the intestinal microbiota composition in colitis mice,especially the increase of the relative abundance of Ruminococcaceae and Lachnospiraceae.This alternation further induced primary bile acids convert into secondary bile acids.With SCS administration,the levels of deoxycholic acid(DCA)and litho cholic acid(LCA)were increased by 1.5-and 2.5-fold,respectively.The stimulated secretion of DCA and LCA showed further activation of the NF-κB signaling pathway,thereby suppressing the inflammatory response and attenuating inflammatory bowel disease(IBD)in mice.This study provided a valuable strategy for colitis prevention and treatment with sturgeon cartilage by-products.
基金supported by National Natural Science Foundation of China(32072145)。
文摘Sea cucumber derived sulfated sterols significantly ameliorated insulin resistance and decreased lipid accumulation compared to plant sterols.Interestingly,our recent study found that intervention with sea cucumber sulfated sterols could significantly increase blood glucose levels of healthy mice in the presence of glucose,while cholesterol sulfate,as one of sulfated sterols,did not have the same effect.However,the exact mechanism of sulfated sterols on glucose metabolism is still unknown.In the present study,we investigated the potential mechanism by which sulfated sterols influenced blood glucose homeostasis in healthy mice.Results showed that intervention with sea cucumber sulfated sterols did not affect the levels of hormones related to glucose metabolism,while led to a significant decrease in the synthesis of liver glycogen and muscle glycogen.Besides,the expression of proteins associated with the promotion of gluconeogenesis dramatically increased in the mice intervened with sea cucumber sulfated sterols.These findings suggested that sea cucumber sulfated sterols might change blood glucose metabolism in healthy mice by reducing glycogenesis and promoting gluconeogenesis.
基金Project supported by the National Key Research and Development Program(2022YFC3204900)Jiangsu Province Construction System Technology Project(2023ZD108)。
文摘Sulfamethoxazole(SMZ)is a prevalent and recalcitrant micropollutant in water,posing a significant threat to both aquatic organisms and human health.Therefore,investigating the removal of SMZ is of critical importance.In order to investigate the effect of rare earth metal doping on the performance of activated persulfate oxidative degradation of SMZ,BiFeO_(3)with different Ce doping amounts was successfully prepared by a hydrothermal method.Then,it was characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),scanning transmission electro n microscopy(STEM)and Brunauer-Emmett-Teller(BET)method.The performance of porous Ce/BiFeO_(3)in the catalytic activation of persulfate(PMS)for the degradation of SMZ in water was investigated using SMZ solution as a simulated wastewater.The impact of Ce doping rate,catalyst dosage,temperature variations,common anions,natural organic matter,and PMS concentration on SMZ removal was systematically evaluated.The characterization results show that the octahedral rhombic structure of Ce can be observed on the surface of this doped catalyst,and Ce doping does not change the crystalline shape of Ce/BiFeO_(3).The specific surface area of the doped catalyst increases,accompanied by an enlargement of pore size,thereby enhancing the catalyst's adsorption capacity and resistance to contamination by SMZ.Under the optimal conditions of 25℃,SMZ concentration of 20 mg/L,0.8 g/L PMS and 0.3 g/L 0.05Ce/BiFeO_(3)catalyst,the removal rate of SMZ reaches approximately 95%within35 min of reaction time.Even after five cycles of reuse,the degradation rate of SMZ remains above 88%,demonstrating the catalyst's good stability and reusability.Bursting experiments show that SO_(4)^(·-),·OH,1O_(2)and O_(2)^(·-)are involved in the catalytic degradation process,with 1O_(2)playing a dominant role.
基金supported by the National Natural Science Foundation of China(Grant Nos.42372312,and 42172299)the Pyramid Talent Training Project of Beijing University of Civil Engineering and Architecture(Grant No.JDYC20220807).
文摘The progressive failure characteristics of geomaterial are a remarkable and challenging topic in geotechnical engineering.To study the effect of salt content and temperature on the progressive failure characteristics of frozen sodium sulfate saline sandy soil,a series of uniaxial compression tests were performed by integrating digital image correlation(DIC)technology into the testing apparatus.The evolution law of the uniaxial compression strength(UCS),the failure strain,and the formation of the shear band of the frozen sodium sulfate saline sandy soil were analyzed.The test results show that within the scope of this study,with the increase of salt content,both the UCS and the shear band angle initially decrease with increasing salt content before showing an increase.In contrast,the failure strain and the width of the shear band exhibit an initial increase followed by a decrease in the samples.In addition,to investigate the brittle failure characteristics of frozen sodium sulfate saline sandy soil,two classic brittleness evaluation methods were employed to quantitatively assess the brittleness level for the soil samples.The findings suggest that the failure characteristics under all test conditions in this study belong to the transition stage between brittle and ductile,indicating that frozen sodium sulfate saline sandy soil exhibits certain brittle behavior under uniaxial compression conditions,and the brittleness index basically decreases and then increases with the rise in salt content.
基金Funded by Chinese National Natural Science Foundation of China(No.U2006224)。
文摘The paper presents experimental investigation results of crack pattern change in cement pastes caused by external sulfate attack(ESA).To visualize the formation and development of cracks in cement pastes under ESA,an X-ray computed tomography(X-ray CT)was used,i e,the tomography system of Zeiss Xradia 510 versa.The results indicate that X-CT can monitor the development process and distribution characteristics of the internal cracks of cement pastes under ESA with attack time.In addition,the C3A content in the cement significantly affects the damage mode of cement paste specimens during sulfate erosion.The damage of ordinary Portland cement(OPC)pastes subjected to sulfate attack with high C3A content are severe,while the damage of sulfate resistant Portland cement(SRPC)pastes is much smaller than that of OPC pastes.Furthermore,a quadratic function describes the correlation between the crack volume fraction and development depth for two cement pastes immermed in sulfate solution.
文摘A zinc sulfate open framework matrix,[Zn(SO_4)(DMSO)](1),was synthesized by solvothermal evaporationusing dimethyl sulfoxide(DMSO)as the solvent.A compositeP@1,which exhibits fluorescence and room tempera-ture phosphorescence(RTP)properties,was prepared by doping 2,6-naphthalic acid(P)into matrix1at a low con-centration.P@1emitted a green RTP that was visible to the naked eye and lasted for approximately 2 s.P@1exhib-ited selective phosphorescence enhancement response towards Pb^(2+),with a detection limit of 2.52μmol·L^(-1).Themain detection mechanism is the Pb—O coordination-induced phosphorescence enhancement in the system.Inter-estingly,P@1also functioned as a dual-channel probe for the rapid detection of Fe^(3+)ions through fluorescencequenching with a detection limit of 0.038μmol·L^(-1).The recognition mechanism may be attributed to the competi-tive energy absorption betweenP@1and Fe^(3+)ions.CCDC:2388502,1.
基金supported by the National Natural Science Foundation of China(Nos.81930097,82151223)the National Key R&D Program of China(Nos.2022YFF1203005,2022YFC2303700)。
文摘Chondroitin sulfate(CS) B and T are rare subtypes of CS,which are scare in nature.There are also limited synthetic methods to prepare them.Here we report an ingenious semisynthetic approach to prepare a library of disaccharides,tetrasaccharides and hexasaccharides of CS-B and CS-T based on the acid or enzymatic degradation of natural CS polysaccharide in 9 or 10 steps.Our approach is the shortest synthetic route toward size-defined CS-B and CS-T oligosaccharides reported to date.In addition,a regioselective protection method of hydroxyls is highlighted,which has achieved the regioselective protection of 4 hydroxyl groups among 7 equatorial hydroxyl groups.By preparing size-defined rare CS oligosaccharides from commercially available natural CS polysaccharides,this strategy has the potential to meet the need of rare natural oligosaccharides.
文摘Objective:To assess the protective effects of Panax ginseng(PG)against copper sulfate(CuSO_(4))-induced kidney toxicity in rats.Methods:The rats were randomly allocated into four groups:control,CuSO_(4),PG,and PG+CuSO_(4).The experiment continued for 14 days,during which CuSO_(4) was provided at a dosage of 100 mg/kg body weight per day and PG at 300 mg/kg body weight by oral gavage per day.Upon completion of the experiment,kidney sections were used for histological and histomorphometric analyses.The histochemical method was applied to ascertain the density of the glomerular mesangial matrix.The expressions of vascular endothelial growth factor(VEGF)and caspase-3 were examined using immunohistochemistry.The levels of malondialdehyde and glutathione,along with the activity of superoxide dismutase and catalase in the kidney,were measured.Results:PG treatment exhibited a marked protective effect against CuSO_(4)-induced renal damage,as evidenced by improved histopathological lesions,significantly reduced glomerular mesangial matrix density,VEGF in distal tubules,caspase-3 expression,and malondialdehyde levels in renal tissue,as well as enhanced superoxide dismutase and catalase activities.Conclusions:PG treatment ameliorates CuSO_(4)-induced kidney injury in rats.Further studies are warranted to verify its efficacy and elucidate the underlying mechanism of its nephroprotective action.
基金Supported by The Zhejiang Provincial Health Commission,No.2022KY1391.
文摘BACKGROUND Nikethamide,a respiratory stimulant,is used to treat hypoxemia caused by coronavirus disease 2019(COVID-19),but it carries a risk of convulsions.Magnesium sulfate(MgSO_(4)),a seizure inhibitor,might serve as a rescue agent against nikethamide-induced seizures.AIM To investigate the therapeutic effect of MgSO_(4)on nikethamide-induced seizures in COVID-19 patients through animal experiments,providing experimental support for the clinical application of MgSO_(4)in preventing and treating seizures caused by nikethamide.METHODS Forty mice were randomly divided into four groups:(1)Physiological saline;(2)Low-dose MgSO_(4)(50 mg/kg);(3)Medium-dose MgSO_(4)(100 mg/kg);and(4)High-dose MgSO_(4)(200 mg/kg).After 15 minutes of intraperitoneal injection of different doses of MgSO_(4)or an equal volume of physiological saline,the mice were injected with nikethamide(250 mg/kg).RESULTS Compared to the normal saline group,all doses of MgSO_(4)significantly prolonged the seizure latency and reduced the severity of convulsions.However,they also extended the duration of seizures and correspondingly increased survival time(P<0.05).The incidence of seizures and mortality rate in the MgSO_(4)-treated groups were significantly lower than those in the normal saline group(P<0.05).CONCLUSION MgSO_(4)can prevent and treat seizures caused by nikethamide in mice.This finding has implications for the application of MgSO_(4)in treating and preventing seizures caused by nikethamide in COVID-19 treatment.
基金supported by the National Natural Science Foundation of China(No.52160024)the Natural Science Foundation of Hunan Province,China(No.2022JJ30475)+2 种基金the Innovation Team Funds of China West Normal University(No.KCXTD2023-4)the Natural Science Foundation of Sichuan,China(No.24NSFSC0537)the Fundamental Research Funds of China West Normal University(Nos.22kE015 and 22kE016).
文摘As an important component of secondary aerosols,sulfate plays a crucial role in regulating atmospheric radiative balance and influencing the secondary formation of ozone(O_(3)).In real atmosphere,atmospheric oxidants NO_(2)and O_(3)can promote the oxidation of SO_(2)to form sulfate(SO_(4)^(2−))through multiphase chemistry that occur at different time scales.Due to the combined impact of meteorology,pollution sources,atmospheric chemistry,etc.,time-scale dependence of SO_(2)-SO_(4)^(2−)conversion makes the impact of NO_(2)/O_(3)on it more complex.In this study,based on long-term time series(2013-2020)of air pollution variables from seven stations in Hong Kong,the Multifractal Detrended Cross-Correlation Analysis(MFDCCA)method has been employed to quantify the cross-correlations between SO_(2)and SO_(4)^(2−)in real atmosphere at different time scales,for examining the time-scale dependence of SO_(2)-SO_(4)^(2−)conversion efficiency.Furthermore,the Pearson correlation analysis has been used to study the influence of NO_(2)/O_(3)on SO_(2)-SO_(4)^(2−)conversion,and the regional and seasonal differences have been analyzed by considering factors such as meteorology,pollution sources,and regional transport.Changes in the main components of secondary aerosols are closely linked with the co-control of regional PM_(2.5)and O_(3).Therefore,the exploration of the impact of co-existing NO_(2)/O_(3)gases on the secondary formation of sulfates in real atmosphere is significant.
基金supported by the National Natural Science Foundation of China(Nos.52172009 and 12275274)the Science and Technology Project of Fujian Province(Nos.2021J01519 and 2021H0043)the Instrument Developing Project of Chinese Academy of Sciences(No.YJKYYQ20210033)。
文摘Sulfates are always promising short-wave ultraviolet(UV)nonlinear optical(NLO)candidates,if their birefringence could be greatly improved.Here,in terms of the insufficient birefringence,the unity of heteroleptic tetrahedral groups and triangular ones was proposed and implemented.Thus,a new semiorganic crystal,[C(NH_(2))_(3)]S_(3)O_(6)(G_(2)S_(3)O_(6)),was obtained,which is composed of[S_(3)O_(6)]^(2-)and[C(NH_(2))_(3)]+groups.It exhibits excellent optical properties with a short absorption cutoff edge of 218 nm,a strong NLO response of 1.4×KH_(2)PO_(4),and more especially,a large birefringence of 0.097@546 nm.This birefringence leap makes the G_(2)S_(3)O_(6) crystal achieve a phase-matching behavior under a 532 nm laser.Thus,the synergy of[S_(3)O_(6)]^(2-)and[C(NH_(2))_(3)]~+groups results in excellent optical performances.This finding opens a new horizon for exploring novel UV NLO crystals.
基金supported by the Mae Fah Luang University Research Development Grant 2023,Mae Fah Luang University,Chiang Rai Thailand(Grant no.661B07007 to KW)the Technology and Innovation-Based Enterprise Development Fund:Fund(Grant no.YP043/2565 to AO and PW).
文摘Objective:To investigate the effect of synbiotic mulberry on kidney injury in a dextran sodium sulfate(DSS)-induced colitis model.Methods:Male Wistar rats were given drinking water containing 4%DSS for 7 days.Subsequently,the rats were treated by oral gavage with synbiotic mulberry at 250,500,and 1000 mg/kg,sulfasalazine at 100 mg/kg,or synbiotic at 1000 mg/kg for an additional 7 days while receiving 0.4%DSS in drinking water.The severity of colitis was evaluated based on the disease activity index score.On day 14,plasma was collected,and the kidneys were harvested to evaluate kidney injury parameters and histological changes.In addition,the expression of genes associated with kidney injury was determined by quantitative RT-PCR.Results:Treatment with all doses of synbiotic mulberry significantly lowered the disease activity index score,accompanied by reductions in kidney histopathological changes,malondialdehyde concentration,and plasma cystatin C levels.Kidney fibrosis was also ameliorated by 500 and 1000 mg/kg of synbiotic mulberry.Treatment with 250 and 500 mg/kg of synbiotic mulberry downregulated IL-18 mRNA expression,while KIM-1 mRNA expression was reduced and plasma lipopolysaccharide-binding protein level was restored by 1000 mg/kg of synbiotic mulberry.Conclusions:Synbiotic mulberry ameliorates kidney injury in rats with DSS-induced colitis.It may be further explored as a treatment of kidney injury under colitis conditions.
基金Project supported by the Major Research Plan of the National Natural Science Foundation of China(91962211)the National Key Research and Development Program of China(2021YFC2902202)the Key Research and Development Program of Guangxi Province(Guike-AB22080056)。
文摘Aluminum is the main impurity of the weathered crust elution-deposited rare earth ore(WCED-REO).Efficient leaching of rare earths and low leaching of aluminum are of great importance for the leaching of the WCED-REO.The effects of pH,MgSO_(4) concentration and Al^(3+)concentration of the leaching agent solution on the column leaching behaviors of WCED-REO using magnesium sulfate were investigated.Experimental data show that controlling the MgSO_(4) concentration to 0.15 mol/L,pH of the leaching agent solution to 2,the leaching amount of aluminum from the rare earth ore gradually decreases with the increase of Al^(3+)concentration in the leaching agent solution,indicating that Al^(3+)in the leaching agent solution may act as leaching agent to participate in the ion exchange of RE3+,but the leaching amounts of rare earths change insignificantly as the Al^(3+)concentration is increased.Increasing the MgSO_(4) concentration is beneficial to the leaching of aluminum,and when the Al^(3+)concentration is 0.04 mol/L(Al accumulation),the amount of Al^(3+)leached from the rare earth ore increased gradually with increasing the MgSO_(4) concentration.The pH of the leaching agent solution has a significant influence on the leaching of aluminum in the rare earth ore,and the leaching amount of aluminum from the rare earth ore increases gradually with decreasing the pH.When the Al^(3+)conce ntration is 0.04 mol/L(Al accumulation)and the pH of the leaching agent solution is above 2.0,the aluminum in the leaching agent solution can be back-adsorbed onto the rare earth ore,and the amount of the back-adsorbed Al^(3+)increases with increasing the pH of the leaching agent solution.The injection rate of the leaching agent solution has slight effect on the leaching behavior of rare earths and aluminum.In summary,leaching of Al^(3+)and consumption of MgSO_(4) can be reduced by regulating the accumulation of aluminum,MgSO_(4) concentration and pH.
基金the Major Research Plan of the National Natural Science Foundation of China(91962211)the Key Research and Development Program of Guangxi Province(Guike-AB22080056)+1 种基金the Beijing Nova Program(20230484379)the Major Program of Qingyuan Innovation Laboratory(00122004)。
文摘Ion-adsorption rare earth ore(IAREO)is a crucial source of mid-heavy rare earths elements(M-HRE).Reverse osmosis technology is a promising technique for the pre-concentration of the leach solution from in-situ leaching of IAREO.However,calcium sulfate scaling is inevitably formed in sulfate system,causing decreases in the flux and life time of membrane.Herein,to simulate the precipitation behavior of calcium sulfate in the leach solution of IAREO during reverse osmosis,a series of experiments was conducted in binary and quaternary supersaturated calcium sulfate solution systems.Experimental data show that the concentration of Ca^(2+)decreases with the increase of the concentration of Mg^(2+),and in-creases with the increase of the concentration of RE3+in both binary and quaternary systems.Whereas.the influence of Al^(3+)on the concentration of Ca^(2+)is different.This variation of the Ca^(2+)concentration is explained by thermodynamic analysis.The difference of association concentration for Mg^(2+),Al^(3+)and RE^(3+)with SO_(4)^(2-)in binary or quaternary system is the main reason.Finally,the influence and mechanisms of antiscalant on the precipitation behavior of calcium sulfate are discussed.X-ray diffraction(XRD),Zeta potential and scanning electron microscopy(SEM)analyses reveal that polyacrylic acid(PAA)effectively inhibits the crystal growth of calcium sulfate,and the precipitation time of calcium sulfate is prolonged,indicating that PPA is a potential inhibitor for calcium sulfate scaling during the process of reverse osmosis.
基金supported by the National Natural Science Foundation of China(Nos.42222705,42377097,and 22361162668)the National Key Research and Development Program of China(No.2022YFC3701101)+1 种基金the Youth Innovation Promotion Association CAS(No.2021354)Guangdong Foundation for Program of Science and Technology Research(No.2023B1212060049)。
文摘Aqueous-phase reactions between carbonyls and reduced nitrogen compounds play a considerable role in the formation of secondary organic aerosols and brown carbon in the atmosphere.However,the reported reaction rate constants for these reactions have largely been limited to bulk aqueous-phase simulations,which may not accurately represent the real state of atmospheric cloud droplets.We employed an integration of optical tweezers and Raman spectroscopy to manipulate and analyze simulated cloud droplets(size range8000-10,000 nm),comprising a mixture of glyoxal and ammonium sulfate.This approach enabled us to delve into the intricate realm of their reaction kinetics at individual droplet level mimicking cloud droplets.Raman spectroscopy provided high temporal resolution(20 s)measurements of the changes in the amount of nitrogen-containing organics(or NOCs as represented by the C-N bond)within the droplets.The results indicate that the reaction follows first-order kinetics throughout the monitoring over 80-400 min.The average reaction rate constant for the formation of NOCs within the single droplet was determined to be(6.77±0.98)×10^(-5)s^(-1),up to three orders of magnitude higher than those through the bulk aqueous-phase simulations,especially at lower p H levels.Additionally,the reaction rate constant in single droplet increases with increasing p H,consistent with the trend previously reported for the bulk aqueous-phase simulations.The results highlight the difference of the reaction rate constant between bulk aqueous-phase and droplets,which would improve our understanding on the formation and impacts of secondary organic aerosols and brown carbon in atmospheric aqueous phase.
基金supported by the National Natural Science Foun-dation of China(12362032)the Key Research and Development Pro-gram of Gansu Province-Social Development(23YFFA0063).
文摘In order to explore the mechanical properties and microstructure changes of frozen saline silty clay in the Hexi region of Gansu Province,triaxial compression tests and scanning electron microscopy(SEM)analysis experiment were conducted to explore the effects of moisture content,confining pressure,and temperature on the stress-strain characteristics and failure modes of frozen soil,as well as the changes in the internal microstructure of the sample.The experimental results show that the strength of frozen sulfate saline soil first increases and then decreases with the increase of moisture content,and the maximum strength corresponds to a moisture content of 15%.The changes in confining pressure and strength have the same trend.The lower the temperature,the greater the strength of the sample.During the entire loading process,the specimens undergo a gradual transition from volume shrinkage to volume expansion.Due to the strain harden behavior of the stress-strain curve throughout the entire loading process,the failure mode of the specimens is plastic failure.The internal microstructure of the sample gradually transitions from point-point contact and edge-point contact before shearing to edge-surface contact and edge-edge contact after shearing,and the pore size inside the sample increases after shearing,with a loose arrangement of the particle skeleton.The above research conclusions can lay a certain theoretical foun-dation for the engineering design and construction of sulfate saline soil in cold and arid areas.
基金supported by the National Natural Science Foundation of China(Nos.42077198 and 22206023)Liaoning Revitalization Talents Program(No.XLYC1907185)+1 种基金Liaoning Science and Technology Joint Project(No.2023-MSBA-109)the Fundamental Research Funds for the Central Universities(Nos.N2325019 and N2325034).
文摘The photochemical conversion of SO_(2) to sulfates on 4-(benzoyl)benzoic acid(4-BBA)was investigated deeply in the presence of anionic and cationic surfactants.The types of surfactants determined their effect behaviors,and cationic surfactants can significantly enhance the SO_(2) oxidation on 4-BBA under irradiation,as shown by larger SO_(2) uptake coefficients and sulfate production.Hydrophilic moieties in cationic surfactants have a greater enhancement effect on the photochemical conversion of SO_(2) to sulfates than the corresponding hydrophobic moieties.Cationic surfactants obviously increased the accumulation of H_(2)O on the surface,which was proved to be the main factor influencing the SO_(2) uptake and the sulfate formation on 4-BBA.SO_(2) lifetime and sulfate formation rate in the mixture system of photosensitive substances with surfactants were evaluated to be 2.25 days and 0.09μg/(m^(3)·h),respectively.
基金supported by the National Natural Science Foundation of China(12362032)the Key Research and Development Program of Gansu Province-Social Development(25YFGA072)+2 种基金Natural Science Foundation of Gansu Province(22JR5RA805)Key Research and Development and Transformation Program of Qinghai Province(2025-QY-217)Gansu Province University Industry Support Plan(2025CYZC-033).
文摘The engineering diseases caused by seasonal sulfate saline soil in Hexi region of Gansu Province seriously affect the local infrastructure construction and operation maintenance.To address this issue,this study explored the thermal mass transfer law,pore fluid phase transition,soil deformation and microstructure of unsaturated sulfate saline soil under the open system.Firstly,based on the theories of porous media mechanics and continuum mechanics,combined with the conservation equations of mass,energy and momentum and considering the phase transition of pore fluid,a multi-field coupled mathematical model of hydro-thermal-salt-gasmechanical for unsaturated sulfate saline soil was established.Secondly,basic unknown variables such as pore water pressure,concentration,temperature,porosity,and displacement were selected to perform numerical simulation analysis on the equation system by“Comsol Multiphysics”finite element method.Finally,a comparative analysis was conducted between the on-site measured data and the numerical simulation results.The results show that the water and salt phase transitions caused by temperature change could lead to soil salt heave and frost heave,alter the pore structure of the soil,and reduce the compactness of the soil,ultimately being reflected in the changes in soil porosity.The influence of external temperature on soil temperature gradually decreases with increasing depth,and the sensitivity of frozen areas to external temperature is much higher than that of unfrozen areas.This study not only enriches the theoretical results of thermal mass transfer law and deformation of unsaturated sulfate saline soil,but also provides practical guidance for the prevention and control of engineering diseases in local sulfate saline soil.
基金supported by the National Natural Science Foundation of China(51769013,52168052)。
文摘Intense evaporation in areas with loess-like sulfate saline soils has resulted in significant ecological challenges that include water shortages and soil salinization.Investigating evaporation rate in loess-like sulfate saline soils under varying salt contents carries crucial implications for understanding regional water loss processes,predicting soil salinization advancement,and formulating effective ecological management strategies.Therefore,this study sampled the loess-like sulfate saline soil that is widely distributed in western China as experimental materials and investigated the impact of different initial salt contents(0.00%,0.50%,1.50%,3.00%,and 5.00%)on the evaporation rate,water content,and temperature of soil.The results showed that the evaporation rate decreased with increasing initial salt content.After a salt accumulation layer formed on the soil surface,the water content of the surface soil fluctuated.An increase in the initial salt content resulted in a corresponding increase in the surface temperature.Considering the evaporation characteristics of loess-like sulfate saline soil and the impact of an anomalous increase in surface soil water content on soil surface resistance,this study proposed a modified evaporation model on the basis of Fujimaki's evaporation model of saline soil by introducing a correction coefficientβto modify the soil surface resistance.A comparison of the calculated evaporation rates before and after the modification with the measured evaporation rates revealed a significant improvement in the calculation accuracy of the modified model,indicating that the modified model is capable of more accurately simulating the evaporation rate of sulfate saline soil with different initial salt contents.This paper proposes an effective method for calculating the evaporation rate of loess-like sulfate saline soils,providing a theoretical basis for evaporation research in saline soil.
