Polycyclic Aromatic Hydrocarbons(PAHs),along with their derivatives nitro-PAHs and oxy-PAHs,are globally recognized toxic pollutants.This research conducted daily PM_(2.5)sampling in winter 2021 at three urban(YNCE,SW...Polycyclic Aromatic Hydrocarbons(PAHs),along with their derivatives nitro-PAHs and oxy-PAHs,are globally recognized toxic pollutants.This research conducted daily PM_(2.5)sampling in winter 2021 at three urban(YNCE,SWP,and NG)and three suburban sites(HC,CTV,and YNE)in the Ili River Valley(IRV).For the first time in the IRV,a comprehensive study on 39 PAHs and derivatives was carried out.The results showed that the average∑_(16)PAHs concentration was 130.21±98.94 ng/m^(3),with 16PAHs constituting the dominant fraction(112.51±86.48 ng/m^(3)).The mean BaP and the total BaP equivalent quotient(TEQ)concentrations were 10.28±8.85 ng/m^(3)and 19.74±16.70 ng/m^(3),respectively.Approximately 88%of the daily BaP averages and 98%of the daily TEQ averages exceeded the national daily average standard of BaP(2.5 ng/m^(3)),indicating severe local BaP pollution.Urban sites had notably higher∑PAHs and TEQ concentrations than suburban sites,attributed to increased vehicular traffic and coal combustion in urban areas.PMF results showed that traffic emissions(32.7%-60.5%),coal combustion(13.9%-24.3%)and secondary formation(14.7%-22.7%)were the primary contributors to∑PAHs.Urban sites experienced a greater influence from traffic,while suburban sites were more impacted by coal and biomass burning.On polluted days,traffic sources’contributions increased significantly at HC,YNE,NG and YNCE sites,and secondary formation sources’contributions grew at CTV and YNCE sites.The sourcedependent BaPeq results underscored the role of secondary-formed PAH derivatives in TEQ.展开更多
Background:The use of grafts from donation after circulatory death(DCD)overcomes the inadequate donor organ supply.Our team developed a transportable dual hypothermic oxygenated machine perfusion(DHOPE)device,which in...Background:The use of grafts from donation after circulatory death(DCD)overcomes the inadequate donor organ supply.Our team developed a transportable dual hypothermic oxygenated machine perfusion(DHOPE)device,which initiates DHOPE at a recipient center to reduce static cold storage(SCS)time and the risk of graft failure in DCD liver transplantation.Methods:Six porcine livers per group with 30 min of warm ischemia exposure were preserved via SCS or DHOPE for 6 h and then reperfused for 12 h with whole blood to mimic transplantation.Hepatocellular and biliary function and injury were assessed in perfusate and bile samples.Molecular biomarkers and histology were compared between groups.Results:Reperfusion portal vein pressure,in a flow-constant manner,and alanine aminotransferase(ALT),aspartate aminotransferase(AST),alkaline phosphatase(ALP)and gamma-glutamyltransferase(γ-GGT)release were significantly lower in the DHOPE group than in the SCS group at all time points.Higher bile production paralleled the lower levels of ALP andγ-GGT in the DHOPE group.The DHOPE group secreted more total bilirubin(TBIL)in bile,resulting in decreased TBIL in the perfusate,and livers preserved with DHOPE exhibited better cholangiocellular function.Furthermore,improvements in hypoxia,the inflammatory response,cell-free microRNAs and energy metabolism were observed in the DHOPE group.There were fewer apoptotic cells and TGF-β1-positive cells in the liver parenchyma and extrahepatic bile duct in the DHOPE group than in the SCS group.Conclusions:This study demonstrates the efficacy of local 4℃DHOPE to protect porcine liver grafts from30-min warm ischemia damage.展开更多
Veno-arterial extracorporeal membrane oxygenation(VA-ECMO)is a life support intervention for patients with refractory cardiogenic shock or severe cardiopulmonary failure.However,the choice of cannulation strategy rema...Veno-arterial extracorporeal membrane oxygenation(VA-ECMO)is a life support intervention for patients with refractory cardiogenic shock or severe cardiopulmonary failure.However,the choice of cannulation strategy remains contentious,partly due to insufficient understanding of hemodynamic characteristics associated with the site of arterial cannulation.In this study,a geometrical multiscale model was built to offer a mathematical tool for addressing the issue.The outflow cannula of ECMO was inserted into the ascending aorta in the case of central cannulation,whereas it was inserted into the right subclavian artery(RSA)or the left iliac artery(LIA)in the case of peripheral cannulation.Numerical simulations conducted on three patient-specific aortas demonstrated that the central cannulation outperformed the two types of peripheral cannulation in evenly delivering ECMO flow to branch arteries.Both the central and RSA cannulations could maintain an approximately normal hemodynamic state in the aortas,although the area of aortic walls exposed to abnormal wall shear stress(WSS)was considerably enlarged in comparison with the normal physiological condition.In contrast,the LIA cannulation not only led to insufficient delivery of ECMO flow to the right upper body(with ECMO flow fractions<0.5),but also induced marked flow disturbance in the aorta,causing about 40%of the abdominal aortic wall and over 65%of the resting aortic wall to suffer from high time-averaged WSS(>5 Pa)and low time-averaged WSS(<0.4 Pa),respectively.The LIA cannulation also resulted in significantly prolonged blood residence time(>40 s)in the ascending aorta,which,along with abnormal WSS,may considerably increase the risk of thrombosis.In summary,our numerical study elucidated the impact of arterial cannulation site in VA-ECMO intervention on aortic hemodynamics and ECMO flow distribution.The findings provide compensatory biomechanical information for traditional clinical studies and may serve as a theoretical reference for guiding the evaluation and selection of cannulation strategies in clinical practice.展开更多
The continual growth in transportation fuels and more strict environmental legislations have led to immense interest in developing green biomass energy. In this work, a proposed catalytic transformation of oxygenated ...The continual growth in transportation fuels and more strict environmental legislations have led to immense interest in developing green biomass energy. In this work, a proposed catalytic transformation of oxygenated organic compounds （related to bio-oil） into pure hydrogen was desighed, involving the catalytic reforming of oxygenated organic compounds to hydrogen- rich mixture gas followed by the conversion of CO to CO2 via the water gas reaction and the removal of CO2. The optimization of the different reforming catalyst, the reaction conditions as well as various sources of oxygenated organic compounds were investigated in detail. The production of pure hydrogen, with the H2 content up to 99.96% and the conversion of 97.1%, was achieved by the integrated catalytic transformation. The reaction pathways were addressed based on the investigation of decomposition, catalytic reforming, and the water gas reaction.展开更多
Oxygenated volatile organic compounds（OVOCs） emitted from orange wastes during aerobic decomposition were investigated in a laboratory-controlled incubator for a period of two months. Emission of total OVOCs（TOVOCs...Oxygenated volatile organic compounds（OVOCs） emitted from orange wastes during aerobic decomposition were investigated in a laboratory-controlled incubator for a period of two months. Emission of total OVOCs（TOVOCs） from orange wastes reached 1714 mg/dry kg（330 mg/wet kg）. Ethanol, methanol, ethyl acetate, methyl acetate, 2-butanone and acetaldehyde were the most abundant OVOC species with shares of 26.9%, 24.8%, 20.3%, 13.9%, 2.8%and 2.5%, respectively, in the TOVOCs released. The emission fluxes of the above top five OVOCs were quite trivial in the beginning but increased sharply to form one ＂peak emission window＂ with maximums at days 1-8 until leveling off after 10 days. This type of ＂peak emission window＂ was synchronized with the CO2 fluxes and incubation temperature of the orange wastes, indicating that released OVOCs were mainly derived from secondary metabolites of orange substrates through biotic processes rather than abiotic processes or primary volatilization of the inherent pool in oranges. Acetaldehyde instead had emission fluxes decreasing sharply from its initial maximum to nearly zero in about four days,suggesting that it was inherent rather than secondarily formed. For TOVOCs or all OVOC species except 2-butanone and acetone, over 80% of their emissions occurred during the first week, implying that organic wastes might give off a considerable amount of OVOCs during the early disposal period under aerobic conditions.展开更多
In this work,a modification method of H_(3)PO_(4)plus H_(2)O_(2)(PHP)was introduced to targetedly form abundant oxygenated functional groups(OFGs)on biochar,and methylene blue(MB)was employed as a model pollutant for ...In this work,a modification method of H_(3)PO_(4)plus H_(2)O_(2)(PHP)was introduced to targetedly form abundant oxygenated functional groups(OFGs)on biochar,and methylene blue(MB)was employed as a model pollutant for adsorption to reflect the modification performance.Results indicated that parent biochars,especially derived from lower temperatures,substantially underwent oxidative modification by PHP,and OFGs were targetedly produced.Correspondingly,approximately 21.5-fold MB adsorption capacity was achieved by PHP-modified biochar comparing with its parent biochar.To evaluate the compatibility of PHP-modification,coefficient of variation(CV)based on MB adsorption capacity by the biochar from various precursors was calculated,in which the CV of PHP-modified biochars was 0.0038 comparing to0.64 of the corresponding parent biochars.These results suggested that the PHP method displayed the excellent feedstock compatibility on biochar modification.The maximum MB adsorption capacity was454.1 mg/g when the H_(3)PO_(4)and H_(2)O_(2)fraction in PHP were 65.2%and 7.0%;the modification was further intensified by promoting temperature and duration.Besides,average 94.5%H_(3)PO_(4)was recovered after 10-batch modification,implying 1.0 kg H_(3)PO_(4)(85%)in PHP can maximally modify 2.37 kg biochar.Overall,this work offered a novel method to tailor biochar towards OFGs-rich surface for efficient adsorption.展开更多
The experiments were carried out at the Post Graduate Research Center, to study the influence of Gibberellic Acid (50 ppm) and Oxygenated Peptone (1% aqueous solution) on chick pea (Cicer arietinum L. cv. Vijay) durin...The experiments were carried out at the Post Graduate Research Center, to study the influence of Gibberellic Acid (50 ppm) and Oxygenated Peptone (1% aqueous solution) on chick pea (Cicer arietinum L. cv. Vijay) during germination by giving pre-sowing soaking treatment for 6 hours using petriplate method. Both the treatments enhanced the germination process. GA treatment was useful to increase shoot length, mobilization efficiency, emergence index, speed of germination and co-efficient of germination while oxygenated peptone showed an upper hand in root length, shoot/root ratio, biomass and vigour index. GA led to comparatively more synthesis of nucleic acids while oxygenated peptone showed more increase in total carbohydrates and soluble protein content. However, the activity of enzymes like amylase, catalase and protease showed upper hand with oxygenated peptone as compared to GA. In fact GA is costlier and can not be used in organic farming as it enters metabolic pathways of plant and alters them. Hence the use of oxygenated peptone is recommended being less expensive and usable under organic farming condition as it does not enter the plant metabolic pathways and yet brings about significant positive effect.展开更多
Based on Core GGC-6 from the South China Sea (SCS) and Core GGC-29 from the Sulu Sea,planktonic and benthic foraminifera and organic carbon measurements were used to evaluate the Water mass conditions in these sea are...Based on Core GGC-6 from the South China Sea (SCS) and Core GGC-29 from the Sulu Sea,planktonic and benthic foraminifera and organic carbon measurements were used to evaluate the Water mass conditions in these sea areas during the last glacial age. The results show that the higher organic carbon contents in the SCS and Sulu Sea during the last glacial period were mainly caused by low dissolved oxygen concentrations in bottom waters and that in the last glacial to Holocene, the fluctuation of dissolvd oxygen in the bottom weters was large in the SCS and reatively stable in the Sulu Sea. In addition, increased precipitation reduced surface water salinities, which at the water column to be more stratified in the SCS and Sulu Sea during the last glacial period. This process lowered dissolved oxygen concentrations in bottom waters, which resulted in better preservation of organic matter in both basins.展开更多
Oxygenated carbon materials exhibit outstanding electrocatalytic performance in the production of hydrogen peroxide(H2O2)through a two-electron oxygen reduction reaction.The nature of the active functional group and u...Oxygenated carbon materials exhibit outstanding electrocatalytic performance in the production of hydrogen peroxide(H2O2)through a two-electron oxygen reduction reaction.The nature of the active functional group and underlying reaction mechanism,however,remain unclear.Here,a comprehensive workflow was established to identify the active sites from the numerous possible structures.The common hydroxyl group at the notched edge demonstrates a key role in the two-electron process.The local chemical environment weakens the binding of OOH intermediate to substrate while enhancing interaction with solution,thereby promoting the H_(2)O_(2)production.With increasing pH,the intramolecular hydrogen bond between OOH intermediate and hydroxyl decreases,facilitating OOH desorption.Furthermore,the rise in selectivity with increasing potential stems from the suppression of the four-electron process.The active site was further validated through experiments.Guided by theoretical understanding,optimal performance was achieved with high selectivity(>95%)and current density(2.06 mA/cm^(2))in experiment.展开更多
Vapor wall losses can affect the yields of secondary organic aerosol.The effects of surfaceto-volume(S/V)ratio and relative humidity(RH)on the vapor-wall interactions were investigated in this study.The oxygenated vol...Vapor wall losses can affect the yields of secondary organic aerosol.The effects of surfaceto-volume(S/V)ratio and relative humidity(RH)on the vapor-wall interactions were investigated in this study.The oxygenated volatile organic compounds(OVOCs)were generated from toluene-H_(2)O_(2)irradiations.The average gas to wall loss rate constant(k_(gw))of OVOCs in a 400 L reactor(S/V=7.5 m^(-1))is 2.47(2.41 under humid conditions)times higher than that in a 5000 L reactor(S/V=3.6 m-1)under dry conditions.In contrast,the average desorption rate constant(k_(wg))of OVOCs in 400 L reactor is only 1.37(1.20 under humid conditions)times higher than that in 5000 L reactor under dry conditions.It shows that increasing the S/V ratio can promote the wall losses of OVOCs.By contrast,the RH effect on k_(gw)is not prominent.The average k_(gw)value under humid conditions is almost the same as under dry conditions in the 400 L(5000 L)reactor.However,increasing RH can decrease the desorption rates.The average k_(wg)value under dry conditions is 1.45(1.27)times higher than that under humid conditions in the 400 L(5000 L)reactor.The high RH can increase the partitioning equilibrium timescales and enhance the wall losses of OVOCs.展开更多
Combustion within small motors is key in the application-specific development of nanothermite-based micro-energetic systems. This study evaluates the performance of nanothermite mixtures in a converging-diverging nozz...Combustion within small motors is key in the application-specific development of nanothermite-based micro-energetic systems. This study evaluates the performance of nanothermite mixtures in a converging-diverging nozzle and an open tube. Mixtures were prepared using nano-aluminum(n-Al),potassium perchlorate(KClO_(4)), and different carbon nanomaterials(CNMs) including graphene-oxide(GO), reduced GO, carbon nanotubes(CNTs) and nanofibers(CNFs). The mixtures were packed at different densities and ignited by laser beam. Performance was measured using thrust measurement,high-speed imaging, and computational fluid dynamics modeling, respectively. Thrust, specific impulse(ISP), volumetric impulse(ISV), as well as normalized energy were found to increase notably with CNM content. Two distinctive reaction regimes(fast and slow) were observed in combustion of low and high packing densities(20% and 55%TMD), respectively. Total impulse(IFT) and ISPwere maximized in the 5%GO/Al/KClO_4 mixture, producing 7.95 m N·s and 135.20 s respectively at 20%TMD, an improvement of 57%compared to a GO-free sample(5.05 m N·s and 85.88 s). CFD analysis of the motors over predicts the thrust generated but trends in nozzle layout and packing density agree with those observed experimentally;peak force was maximized by reducing packing density and using an open tube. The numerical force profiles fit better for the nozzle cases than the open tube scenarios due to the rapid nature of combustion. This study reveals the potential of GO in improving oxygenated salt-based nanothermites,and further demonstrates their applicability for micro-propulsion and micro-energetic applications.展开更多
A new highly oxygenated iridoid,lamiophlomiol C,was isolated from the roots of Lamiophlomis rotata and its structure was elucidated by spectrosoopic techniques and X-ray diffraction.
<span style="font-family:Verdana;">The objective of this study was to evaluate the effect of blends of different oxygenated additives on gasoline in SI engine Otto cycle. The formulations analyzed were...<span style="font-family:Verdana;">The objective of this study was to evaluate the effect of blends of different oxygenated additives on gasoline in SI engine Otto cycle. The formulations analyzed were: pure gasoline (type A), common gasoline (type C), gasoline type A + 15% (v/v) oxygenated additives (ethanol, ethyl octanoate, ethyl oleate). The experiments were performed using engine Branco 4-stroke and 2-cylinder, electric dynamometer, exhaust system, control unit composed of Multi-K unit, variable selector and load cell, stroboscope tachometer, fuel supply system and stopwatch. The rotation was conserved at 4400 rpm and wheel power varied from 3 kW to 12 kW, with intervals of 3 kW to obtain hourly consumption curves and brake specific fuel consumption. Even esters and ethanol having lower heat of combustion, hourly consumption was similar to pure gasoline (type A). In relation to the brake specific fuel consumption, increasing the wheel power had a better conversion of the mass of fuel burned into energy. Thus, this study showed that the mixture of gasoline and esters (ethyl octanoate and ethyl oleate) presented good efficiency in terms of consumption. This research contributes to the needs and to the current studi</span><span style="font-family:Verdana;">es in which industries started to add renewable products to petroleum-</span><span style="font-family:Verdana;">derived fuels;in order to obtain more sustainable fuels at lower costs.</span>展开更多
Background:Liver transplantation(LT)is a crucial treatment for end-stage liver disease,but the limited organ supply has led to the use of extended criteria donors(ECD).The implementation of dynamic preservation techni...Background:Liver transplantation(LT)is a crucial treatment for end-stage liver disease,but the limited organ supply has led to the use of extended criteria donors(ECD).The implementation of dynamic preservation techniques like hypothermic oxygenated machine perfusion(HOPE)is crucial in improving outcomes for ECD grafts.However,graft contamination and infection are a concern.This study aimed to evaluate the risk of infections within 10 days from LT between HOPE and static cold storage(SCS)groups and postoperative complications.Methods:A retrospective cohort study was conducted,including LT recipients transplanted at a single-center from March 2016 to June 2023.Patients were divided into HOPE and SCS groups,and propensity score matching was used to select comparable cohorts.Data on patient and donor characteristics were analyzed.Results:After propensity score matching,a cohort of 370(HOPE,n=185;SCS,n=185)patients was selected for analysis.The study found no significant differences in the rate of clinically relevant infections,microbiological positive samples,or donor-derived infections within 10 days between HOPE and SCS groups.Postoperative outcomes,as well as patient and graft survival,were also similar between the two groups.The study showed that HOPE is a feasible and safe approach,with a comparable risk of infection.Conclusions:The study results indicate that HOPE use in LT does not increase the risk of infection and is associated with similar patient and graft survival outcomes compared to SCS.These findings confirm the safety and efficacy of HOPE in LT and its potential to expand the donor pool without compromising recipient outcomes.展开更多
Background:Ischemia reperfusion injury(IRI)is a major contributing factor to organ damage in liver transplantation(LT)impacting donor organ quality and patient survival.IRI-inflicted graft injury can be reduced by usi...Background:Ischemia reperfusion injury(IRI)is a major contributing factor to organ damage in liver transplantation(LT)impacting donor organ quality and patient survival.IRI-inflicted graft injury can be reduced by using hypothermic oxygenated machine perfusion(HOPE)as a preservation strategy instead of static cold storage(SCS).The endothelial glycocalyx is highly sensitive to IRI and its degradation during graft preservation and reperfusion was previously associated with inferior postoperative outcome after LT.Here,we aimed to measure glycocalyx degradation during and after HOPE in order to evaluate its potential for viability-assessment during machine perfusion and outcome prediction in patients undergoing LT.Methods:Glycocalyx degradation was quantified via enzyme-linked immunoassay(ELISA)for its main component syndecan-1(Sdc-1)in serum of 40 patients undergoing LT after HOPE.In addition,Sdc-1 was evaluated at multiple time points during HOPE.Patients were followed up for 3.5 years to assess postoperative complications including morbidity,the development of early allograft dysfunction(EAD)and graft survival.Results:Liver grafts which later developed EAD showed significantly higher Sdc-1 concentrations after 60 min of HOPE compared to grafts exhibiting normal postoperative function(P=0.02).Receiver operating characteristic analysis revealed a strong predictive potential with an area under the curve of 0.73.A cut-off at 808 ng/mL Sdc-1 at 60 min of HOPE allowed identification of a high-risk group with an incidence of EAD of 66.7%.Sdc-1 concentrations increased during all types of HOPE but were significantly higher in HOPE versus dual HOPE(D-HOPE)after 120 min of perfusion(P=0.02).Conclusions:Sdc-1 evaluated at 60 min during HOPE allows prediction of EAD after LT.Accordingly,Sdc-1 should be considered a potential additional biomarker for viability assessment during HOPE.展开更多
Biofuels have extensive available resources and have an immense potential as promising alternative fuels for automobile.The application advantages of biofuels are mainly reflected as particulate matter(PM)reduction,ca...Biofuels have extensive available resources and have an immense potential as promising alternative fuels for automobile.The application advantages of biofuels are mainly reflected as particulate matter(PM)reduction,carbon neutral,greenhouse gases reduction,waste utilization,energy and economic security,and fuel pluralism.Based on the understanding of molecular structure effects of biofuels on soot formation and particles morphology,the effects of alcohols,ethers,esters and biodiesel on spray and combustion process in constant volume bomb in recent years are retrospectively analyzed in this paper.For the mixture,macromolecular ester fuels and polyoxymethylene dimethyl ether(PODE)are conducive to the improvement of liquid spray,while biodiesel,small molecules,dimethyl ether(DME)and alcohols are reversed.Alcohols are advantageous to the extension of mixing time and the increasing of vapor-phase mixture.Through the influence integrated assessment,alcohols show the best performance on the spray,atomization and combustion,while biodiesels show the worst.But in terms of combustion,PODE is the best choice without considering spray and atomization.For binary alternative-diesel fuel blends,methanol or butanol is the best additive based on synthetically considerations on spray,atomization and combustion.To meet the requirements of the fuel application of diesel engine,ternary fuel or even quaternary fuel have been proposed and explored.This review can help to form a systematic understanding on fuel recombining and obtain the guide of clean and efficient fuel formulation for diesel engine.展开更多
The direct electrochemical synthesis of H_(2)O_(2)from O_(2)is currently the most promising alternative to energyintensive industrial anthraquinone oxidation/reduction methods. However, its widespread use is hampered ...The direct electrochemical synthesis of H_(2)O_(2)from O_(2)is currently the most promising alternative to energyintensive industrial anthraquinone oxidation/reduction methods. However, its widespread use is hampered by the lack of efficient low-cost electrocatalysts. In the current study,oxygenated boron-doped carbon(O-BC) materials were realized via a green synthetic strategy involving polymer dehalogenation and employed as electrode materials for the electrochemical synthesis of H_(2)O_(2)via a 2 e-oxygen reduction.The catalytic activity of the O-BC materials was optimized through systematic variation of the boron source(H_(2)BO_(2))dosage and annealing temperature. Electrochemical measurements revealed that the optimal sample(O-BC-2-650)exhibited a selectivity of 98% for the 2 e-oxygen reduction to H2 O_(2)and an average H_(2)O_(2)production rate of412.8 mmol g_(cat)^(-1) h^(-1)in an H-type alkaline electrolyzer. Density functional theory simulations indicated that the functionalization of active B sites with one oxygen atom provides the lowest Gibbs free energy change(ΔG) of 0.03 e V for the hydrogenation of*O_(2), while functionalization with zero or two O atoms results in much larger ΔG values(0.08 and 0.10 e V,respectively). Thus, this work details a new type of green, lowcost, and metal-free electrocatalyst for H_(2)O_(2)production.展开更多
Oxygenated organic molecules(OOMs)play an important role in the formation of secondary organic aerosols(SOAs),but the mixing states of OOMs are still unclear.This study investigates the mixing states of OOM-containing...Oxygenated organic molecules(OOMs)play an important role in the formation of secondary organic aerosols(SOAs),but the mixing states of OOMs are still unclear.This study investigates the mixing states of OOM-containing single particles from the measurements taken using a single particle aerosol mass spectrometer in Guangzhou,China in 2022.Generally,the particle counts of OOM particles and the mass concentration of secondary organic carbon(SOC)exhibited similar temporal trends throughout the entire year.The OOM particles were consistently enriched in secondary ions,including ^(16)O^(−),^(26)CN^(−),^(46)NO_(2)^(−),^(62)NO_(3)^(−),and ^(97)HSO_(4)^(−).In contrast,the number fractions and diurnal patterns of OOM particles among the total detected particles showed similar distributions in August and October;however,the SOC ratios in fine particulate matter were quite different,suggesting that there were different mixing states of single-particle oxygenated organics.In addition,further classification results indicated that the OOM particles were more aged in October than August,even though the SOC ratios were higher in August.Furthermore,the distribution of hydrocarbon fragments exhibited a notable decrease from January to October,emphasizing the more aged state of the organics in October.In addition,the sharp increase in elemental carbon(EC)-OOM particles in the afternoon in October suggests the potential role of EC in the aging process of organics.Overall,in contrast to the bulk analysis of SOC mass concentration,the mixing states of the OOM particles provide insights into the formation process of SOAs in field studies.展开更多
Oxygenated fuels are known to reduce particulate matter(PM)emissions from diesel engines.In this study,100%soy methyl ester(SME)biodiesel fuel(B100)and a blend of 10%acetal denoted by A-diesel with diesel fuel were te...Oxygenated fuels are known to reduce particulate matter(PM)emissions from diesel engines.In this study,100%soy methyl ester(SME)biodiesel fuel(B100)and a blend of 10%acetal denoted by A-diesel with diesel fuel were tested as oxygenated fuels.Particle size and number distributions from a diesel engine fueled with oxygenated fuels and base diesel fuel were measured using an Electrical Low Pressure Impactor(ELPI).Measurements were made at ten steady-state operational modes of various loads at two engine speeds.It was found that the geometric mean diameters of particles from SME and Adiesel were lower than that from base diesel fuel.Compared to diesel fuel,SME emitted more ultra-fine particles at rated speed while emitting less ultra-fine particles at maximum speed.Ultra-fine particle number concentrations of A-diesel were much higher than those of base diesel fuel at most test modes.展开更多
Ischemia–reperfusion injury is a common pathophysiological mechanism in retinal degeneration.PANoptosis is a newly defined integral form of regulated cell death that combines the key features of pyroptosis,apoptosis,...Ischemia–reperfusion injury is a common pathophysiological mechanism in retinal degeneration.PANoptosis is a newly defined integral form of regulated cell death that combines the key features of pyroptosis,apoptosis,and necroptosis.Oligomerization of mitochondrial voltage-dependent anion channel 1 is an important pathological event in regulating cell death in retinal ischemia–reperfusion injury.However,its role in PANoptosis remains largely unknown.In this study,we demonstrated that voltage-dependent anion channel 1 oligomerization-mediated mitochondrial dysfunction was associated with PANoptosis in retinal ischemia–reperfusion injury.Inhibition of voltage-dependent anion channel 1 oligomerization suppressed mitochondrial dysfunction and PANoptosis in retinal cells subjected to ischemia–reperfusion injury.Mechanistically,mitochondria-derived reactive oxygen species played a central role in the voltagedependent anion channel 1-mediated regulation of PANoptosis by promoting PANoptosome assembly.Moreover,inhibiting voltage-dependent anion channel 1 oligomerization protected against PANoptosis in the retinas of rats subjected to ischemia–reperfusion injury.Overall,our findings reveal the critical role of voltage-dependent anion channel 1 oligomerization in regulating PANoptosis in retinal ischemia–reperfusion injury,highlighting voltage-dependent anion channel 1 as a promising therapeutic target.展开更多
基金supported by the National Key R&D Program of China(No.2017YFC0212501)the Fundamental Research Funds for the Central Universities(No.2021YJSMT09)the research project on deep source apportionment of urban air pollution and pollution control strategies in the core area of the Ili River Valley。
文摘Polycyclic Aromatic Hydrocarbons(PAHs),along with their derivatives nitro-PAHs and oxy-PAHs,are globally recognized toxic pollutants.This research conducted daily PM_(2.5)sampling in winter 2021 at three urban(YNCE,SWP,and NG)and three suburban sites(HC,CTV,and YNE)in the Ili River Valley(IRV).For the first time in the IRV,a comprehensive study on 39 PAHs and derivatives was carried out.The results showed that the average∑_(16)PAHs concentration was 130.21±98.94 ng/m^(3),with 16PAHs constituting the dominant fraction(112.51±86.48 ng/m^(3)).The mean BaP and the total BaP equivalent quotient(TEQ)concentrations were 10.28±8.85 ng/m^(3)and 19.74±16.70 ng/m^(3),respectively.Approximately 88%of the daily BaP averages and 98%of the daily TEQ averages exceeded the national daily average standard of BaP(2.5 ng/m^(3)),indicating severe local BaP pollution.Urban sites had notably higher∑PAHs and TEQ concentrations than suburban sites,attributed to increased vehicular traffic and coal combustion in urban areas.PMF results showed that traffic emissions(32.7%-60.5%),coal combustion(13.9%-24.3%)and secondary formation(14.7%-22.7%)were the primary contributors to∑PAHs.Urban sites experienced a greater influence from traffic,while suburban sites were more impacted by coal and biomass burning.On polluted days,traffic sources’contributions increased significantly at HC,YNE,NG and YNCE sites,and secondary formation sources’contributions grew at CTV and YNCE sites.The sourcedependent BaPeq results underscored the role of secondary-formed PAH derivatives in TEQ.
基金supported by grants from 2020 Guangdong Provincial and Municipal Joint Fund For Basic and Applied Basic Research Project(2020B1515120031)2020 Foshan Municipal Deng Fang Distinguished Research Program(2020A007)+2 种基金Key Scientific Research Program for the development of Ex vivo Liver Perfusion System of Foshan City,China[(2019)No.42]Science and Technol-ogy Program of Guangzhou(202002030201)Guangzhou Sci-ence and Technology Plan(2025A04J3674)。
文摘Background:The use of grafts from donation after circulatory death(DCD)overcomes the inadequate donor organ supply.Our team developed a transportable dual hypothermic oxygenated machine perfusion(DHOPE)device,which initiates DHOPE at a recipient center to reduce static cold storage(SCS)time and the risk of graft failure in DCD liver transplantation.Methods:Six porcine livers per group with 30 min of warm ischemia exposure were preserved via SCS or DHOPE for 6 h and then reperfused for 12 h with whole blood to mimic transplantation.Hepatocellular and biliary function and injury were assessed in perfusate and bile samples.Molecular biomarkers and histology were compared between groups.Results:Reperfusion portal vein pressure,in a flow-constant manner,and alanine aminotransferase(ALT),aspartate aminotransferase(AST),alkaline phosphatase(ALP)and gamma-glutamyltransferase(γ-GGT)release were significantly lower in the DHOPE group than in the SCS group at all time points.Higher bile production paralleled the lower levels of ALP andγ-GGT in the DHOPE group.The DHOPE group secreted more total bilirubin(TBIL)in bile,resulting in decreased TBIL in the perfusate,and livers preserved with DHOPE exhibited better cholangiocellular function.Furthermore,improvements in hypoxia,the inflammatory response,cell-free microRNAs and energy metabolism were observed in the DHOPE group.There were fewer apoptotic cells and TGF-β1-positive cells in the liver parenchyma and extrahepatic bile duct in the DHOPE group than in the SCS group.Conclusions:This study demonstrates the efficacy of local 4℃DHOPE to protect porcine liver grafts from30-min warm ischemia damage.
基金supported by the National Natural Science Foundation of China(Grant Nos.12372309,12061131015).
文摘Veno-arterial extracorporeal membrane oxygenation(VA-ECMO)is a life support intervention for patients with refractory cardiogenic shock or severe cardiopulmonary failure.However,the choice of cannulation strategy remains contentious,partly due to insufficient understanding of hemodynamic characteristics associated with the site of arterial cannulation.In this study,a geometrical multiscale model was built to offer a mathematical tool for addressing the issue.The outflow cannula of ECMO was inserted into the ascending aorta in the case of central cannulation,whereas it was inserted into the right subclavian artery(RSA)or the left iliac artery(LIA)in the case of peripheral cannulation.Numerical simulations conducted on three patient-specific aortas demonstrated that the central cannulation outperformed the two types of peripheral cannulation in evenly delivering ECMO flow to branch arteries.Both the central and RSA cannulations could maintain an approximately normal hemodynamic state in the aortas,although the area of aortic walls exposed to abnormal wall shear stress(WSS)was considerably enlarged in comparison with the normal physiological condition.In contrast,the LIA cannulation not only led to insufficient delivery of ECMO flow to the right upper body(with ECMO flow fractions<0.5),but also induced marked flow disturbance in the aorta,causing about 40%of the abdominal aortic wall and over 65%of the resting aortic wall to suffer from high time-averaged WSS(>5 Pa)and low time-averaged WSS(<0.4 Pa),respectively.The LIA cannulation also resulted in significantly prolonged blood residence time(>40 s)in the ascending aorta,which,along with abnormal WSS,may considerably increase the risk of thrombosis.In summary,our numerical study elucidated the impact of arterial cannulation site in VA-ECMO intervention on aortic hemodynamics and ECMO flow distribution.The findings provide compensatory biomechanical information for traditional clinical studies and may serve as a theoretical reference for guiding the evaluation and selection of cannulation strategies in clinical practice.
文摘The continual growth in transportation fuels and more strict environmental legislations have led to immense interest in developing green biomass energy. In this work, a proposed catalytic transformation of oxygenated organic compounds （related to bio-oil） into pure hydrogen was desighed, involving the catalytic reforming of oxygenated organic compounds to hydrogen- rich mixture gas followed by the conversion of CO to CO2 via the water gas reaction and the removal of CO2. The optimization of the different reforming catalyst, the reaction conditions as well as various sources of oxygenated organic compounds were investigated in detail. The production of pure hydrogen, with the H2 content up to 99.96% and the conversion of 97.1%, was achieved by the integrated catalytic transformation. The reaction pathways were addressed based on the investigation of decomposition, catalytic reforming, and the water gas reaction.
基金supported by the Ministry of Science and Technology of China (No. 2012IM030700)the National Natural Science Foundation of China (Nos. 41025012, U0833003, 41273095 and 41103067)
文摘Oxygenated volatile organic compounds（OVOCs） emitted from orange wastes during aerobic decomposition were investigated in a laboratory-controlled incubator for a period of two months. Emission of total OVOCs（TOVOCs） from orange wastes reached 1714 mg/dry kg（330 mg/wet kg）. Ethanol, methanol, ethyl acetate, methyl acetate, 2-butanone and acetaldehyde were the most abundant OVOC species with shares of 26.9%, 24.8%, 20.3%, 13.9%, 2.8%and 2.5%, respectively, in the TOVOCs released. The emission fluxes of the above top five OVOCs were quite trivial in the beginning but increased sharply to form one ＂peak emission window＂ with maximums at days 1-8 until leveling off after 10 days. This type of ＂peak emission window＂ was synchronized with the CO2 fluxes and incubation temperature of the orange wastes, indicating that released OVOCs were mainly derived from secondary metabolites of orange substrates through biotic processes rather than abiotic processes or primary volatilization of the inherent pool in oranges. Acetaldehyde instead had emission fluxes decreasing sharply from its initial maximum to nearly zero in about four days,suggesting that it was inherent rather than secondarily formed. For TOVOCs or all OVOC species except 2-butanone and acetone, over 80% of their emissions occurred during the first week, implying that organic wastes might give off a considerable amount of OVOCs during the early disposal period under aerobic conditions.
基金the National Natural Science Foundation of China(No.21978183)。
文摘In this work,a modification method of H_(3)PO_(4)plus H_(2)O_(2)(PHP)was introduced to targetedly form abundant oxygenated functional groups(OFGs)on biochar,and methylene blue(MB)was employed as a model pollutant for adsorption to reflect the modification performance.Results indicated that parent biochars,especially derived from lower temperatures,substantially underwent oxidative modification by PHP,and OFGs were targetedly produced.Correspondingly,approximately 21.5-fold MB adsorption capacity was achieved by PHP-modified biochar comparing with its parent biochar.To evaluate the compatibility of PHP-modification,coefficient of variation(CV)based on MB adsorption capacity by the biochar from various precursors was calculated,in which the CV of PHP-modified biochars was 0.0038 comparing to0.64 of the corresponding parent biochars.These results suggested that the PHP method displayed the excellent feedstock compatibility on biochar modification.The maximum MB adsorption capacity was454.1 mg/g when the H_(3)PO_(4)and H_(2)O_(2)fraction in PHP were 65.2%and 7.0%;the modification was further intensified by promoting temperature and duration.Besides,average 94.5%H_(3)PO_(4)was recovered after 10-batch modification,implying 1.0 kg H_(3)PO_(4)(85%)in PHP can maximally modify 2.37 kg biochar.Overall,this work offered a novel method to tailor biochar towards OFGs-rich surface for efficient adsorption.
文摘The experiments were carried out at the Post Graduate Research Center, to study the influence of Gibberellic Acid (50 ppm) and Oxygenated Peptone (1% aqueous solution) on chick pea (Cicer arietinum L. cv. Vijay) during germination by giving pre-sowing soaking treatment for 6 hours using petriplate method. Both the treatments enhanced the germination process. GA treatment was useful to increase shoot length, mobilization efficiency, emergence index, speed of germination and co-efficient of germination while oxygenated peptone showed an upper hand in root length, shoot/root ratio, biomass and vigour index. GA led to comparatively more synthesis of nucleic acids while oxygenated peptone showed more increase in total carbohydrates and soluble protein content. However, the activity of enzymes like amylase, catalase and protease showed upper hand with oxygenated peptone as compared to GA. In fact GA is costlier and can not be used in organic farming as it enters metabolic pathways of plant and alters them. Hence the use of oxygenated peptone is recommended being less expensive and usable under organic farming condition as it does not enter the plant metabolic pathways and yet brings about significant positive effect.
文摘Based on Core GGC-6 from the South China Sea (SCS) and Core GGC-29 from the Sulu Sea,planktonic and benthic foraminifera and organic carbon measurements were used to evaluate the Water mass conditions in these sea areas during the last glacial age. The results show that the higher organic carbon contents in the SCS and Sulu Sea during the last glacial period were mainly caused by low dissolved oxygen concentrations in bottom waters and that in the last glacial to Holocene, the fluctuation of dissolvd oxygen in the bottom weters was large in the SCS and reatively stable in the Sulu Sea. In addition, increased precipitation reduced surface water salinities, which at the water column to be more stratified in the SCS and Sulu Sea during the last glacial period. This process lowered dissolved oxygen concentrations in bottom waters, which resulted in better preservation of organic matter in both basins.
基金supported by the National Natural Science Foundation of China(No.52171022,No.22105214)Zhejiang Provincial Natural Science Foundation of China(Grant No.LXR22B030001)+3 种基金Fujian Institute of Innovation and Chinese Academy of Sciences.K.C.Wong Education Foundation(GJTD-2019-13)the National Key Research and Development Program of China(2019YFB2203400)Ningbo Yongjiang Talent Introduction Programme(2021A-036-B)NingBo S&T Innovation 2025 Major Special Programme(No:2020z059)and the“111 Project”(B20030).
文摘Oxygenated carbon materials exhibit outstanding electrocatalytic performance in the production of hydrogen peroxide(H2O2)through a two-electron oxygen reduction reaction.The nature of the active functional group and underlying reaction mechanism,however,remain unclear.Here,a comprehensive workflow was established to identify the active sites from the numerous possible structures.The common hydroxyl group at the notched edge demonstrates a key role in the two-electron process.The local chemical environment weakens the binding of OOH intermediate to substrate while enhancing interaction with solution,thereby promoting the H_(2)O_(2)production.With increasing pH,the intramolecular hydrogen bond between OOH intermediate and hydroxyl decreases,facilitating OOH desorption.Furthermore,the rise in selectivity with increasing potential stems from the suppression of the four-electron process.The active site was further validated through experiments.Guided by theoretical understanding,optimal performance was achieved with high selectivity(>95%)and current density(2.06 mA/cm^(2))in experiment.
基金supported by the National Key R&D Program of China(No.2017YFC0210005)the National Natural Science Foundation of China(Nos.41875166,41875163 and 41375129)
文摘Vapor wall losses can affect the yields of secondary organic aerosol.The effects of surfaceto-volume(S/V)ratio and relative humidity(RH)on the vapor-wall interactions were investigated in this study.The oxygenated volatile organic compounds(OVOCs)were generated from toluene-H_(2)O_(2)irradiations.The average gas to wall loss rate constant(k_(gw))of OVOCs in a 400 L reactor(S/V=7.5 m^(-1))is 2.47(2.41 under humid conditions)times higher than that in a 5000 L reactor(S/V=3.6 m-1)under dry conditions.In contrast,the average desorption rate constant(k_(wg))of OVOCs in 400 L reactor is only 1.37(1.20 under humid conditions)times higher than that in 5000 L reactor under dry conditions.It shows that increasing the S/V ratio can promote the wall losses of OVOCs.By contrast,the RH effect on k_(gw)is not prominent.The average k_(gw)value under humid conditions is almost the same as under dry conditions in the 400 L(5000 L)reactor.However,increasing RH can decrease the desorption rates.The average k_(wg)value under dry conditions is 1.45(1.27)times higher than that under humid conditions in the 400 L(5000 L)reactor.The high RH can increase the partitioning equilibrium timescales and enhance the wall losses of OVOCs.
基金financial funding from the Egyptian governmentthe financial funding from the NSERC Discovery grant。
文摘Combustion within small motors is key in the application-specific development of nanothermite-based micro-energetic systems. This study evaluates the performance of nanothermite mixtures in a converging-diverging nozzle and an open tube. Mixtures were prepared using nano-aluminum(n-Al),potassium perchlorate(KClO_(4)), and different carbon nanomaterials(CNMs) including graphene-oxide(GO), reduced GO, carbon nanotubes(CNTs) and nanofibers(CNFs). The mixtures were packed at different densities and ignited by laser beam. Performance was measured using thrust measurement,high-speed imaging, and computational fluid dynamics modeling, respectively. Thrust, specific impulse(ISP), volumetric impulse(ISV), as well as normalized energy were found to increase notably with CNM content. Two distinctive reaction regimes(fast and slow) were observed in combustion of low and high packing densities(20% and 55%TMD), respectively. Total impulse(IFT) and ISPwere maximized in the 5%GO/Al/KClO_4 mixture, producing 7.95 m N·s and 135.20 s respectively at 20%TMD, an improvement of 57%compared to a GO-free sample(5.05 m N·s and 85.88 s). CFD analysis of the motors over predicts the thrust generated but trends in nozzle layout and packing density agree with those observed experimentally;peak force was maximized by reducing packing density and using an open tube. The numerical force profiles fit better for the nozzle cases than the open tube scenarios due to the rapid nature of combustion. This study reveals the potential of GO in improving oxygenated salt-based nanothermites,and further demonstrates their applicability for micro-propulsion and micro-energetic applications.
文摘A new highly oxygenated iridoid,lamiophlomiol C,was isolated from the roots of Lamiophlomis rotata and its structure was elucidated by spectrosoopic techniques and X-ray diffraction.
文摘<span style="font-family:Verdana;">The objective of this study was to evaluate the effect of blends of different oxygenated additives on gasoline in SI engine Otto cycle. The formulations analyzed were: pure gasoline (type A), common gasoline (type C), gasoline type A + 15% (v/v) oxygenated additives (ethanol, ethyl octanoate, ethyl oleate). The experiments were performed using engine Branco 4-stroke and 2-cylinder, electric dynamometer, exhaust system, control unit composed of Multi-K unit, variable selector and load cell, stroboscope tachometer, fuel supply system and stopwatch. The rotation was conserved at 4400 rpm and wheel power varied from 3 kW to 12 kW, with intervals of 3 kW to obtain hourly consumption curves and brake specific fuel consumption. Even esters and ethanol having lower heat of combustion, hourly consumption was similar to pure gasoline (type A). In relation to the brake specific fuel consumption, increasing the wheel power had a better conversion of the mass of fuel burned into energy. Thus, this study showed that the mixture of gasoline and esters (ethyl octanoate and ethyl oleate) presented good efficiency in terms of consumption. This research contributes to the needs and to the current studi</span><span style="font-family:Verdana;">es in which industries started to add renewable products to petroleum-</span><span style="font-family:Verdana;">derived fuels;in order to obtain more sustainable fuels at lower costs.</span>
文摘Background:Liver transplantation(LT)is a crucial treatment for end-stage liver disease,but the limited organ supply has led to the use of extended criteria donors(ECD).The implementation of dynamic preservation techniques like hypothermic oxygenated machine perfusion(HOPE)is crucial in improving outcomes for ECD grafts.However,graft contamination and infection are a concern.This study aimed to evaluate the risk of infections within 10 days from LT between HOPE and static cold storage(SCS)groups and postoperative complications.Methods:A retrospective cohort study was conducted,including LT recipients transplanted at a single-center from March 2016 to June 2023.Patients were divided into HOPE and SCS groups,and propensity score matching was used to select comparable cohorts.Data on patient and donor characteristics were analyzed.Results:After propensity score matching,a cohort of 370(HOPE,n=185;SCS,n=185)patients was selected for analysis.The study found no significant differences in the rate of clinically relevant infections,microbiological positive samples,or donor-derived infections within 10 days between HOPE and SCS groups.Postoperative outcomes,as well as patient and graft survival,were also similar between the two groups.The study showed that HOPE is a feasible and safe approach,with a comparable risk of infection.Conclusions:The study results indicate that HOPE use in LT does not increase the risk of infection and is associated with similar patient and graft survival outcomes compared to SCS.These findings confirm the safety and efficacy of HOPE in LT and its potential to expand the donor pool without compromising recipient outcomes.
文摘Background:Ischemia reperfusion injury(IRI)is a major contributing factor to organ damage in liver transplantation(LT)impacting donor organ quality and patient survival.IRI-inflicted graft injury can be reduced by using hypothermic oxygenated machine perfusion(HOPE)as a preservation strategy instead of static cold storage(SCS).The endothelial glycocalyx is highly sensitive to IRI and its degradation during graft preservation and reperfusion was previously associated with inferior postoperative outcome after LT.Here,we aimed to measure glycocalyx degradation during and after HOPE in order to evaluate its potential for viability-assessment during machine perfusion and outcome prediction in patients undergoing LT.Methods:Glycocalyx degradation was quantified via enzyme-linked immunoassay(ELISA)for its main component syndecan-1(Sdc-1)in serum of 40 patients undergoing LT after HOPE.In addition,Sdc-1 was evaluated at multiple time points during HOPE.Patients were followed up for 3.5 years to assess postoperative complications including morbidity,the development of early allograft dysfunction(EAD)and graft survival.Results:Liver grafts which later developed EAD showed significantly higher Sdc-1 concentrations after 60 min of HOPE compared to grafts exhibiting normal postoperative function(P=0.02).Receiver operating characteristic analysis revealed a strong predictive potential with an area under the curve of 0.73.A cut-off at 808 ng/mL Sdc-1 at 60 min of HOPE allowed identification of a high-risk group with an incidence of EAD of 66.7%.Sdc-1 concentrations increased during all types of HOPE but were significantly higher in HOPE versus dual HOPE(D-HOPE)after 120 min of perfusion(P=0.02).Conclusions:Sdc-1 evaluated at 60 min during HOPE allows prediction of EAD after LT.Accordingly,Sdc-1 should be considered a potential additional biomarker for viability assessment during HOPE.
基金supported by the Key Research and Development Program of Shaanxi Province(2019ZDLGY15-07)the National Natural Science Foundation of China(51806020)+1 种基金the Youth Innovation Team of Shaanxi Universities(Energy Saving and New Energy Vehicles)the Special Fund for Basic Scientific Research of Central Colleges,Chang’an University(300102229104)。
文摘Biofuels have extensive available resources and have an immense potential as promising alternative fuels for automobile.The application advantages of biofuels are mainly reflected as particulate matter(PM)reduction,carbon neutral,greenhouse gases reduction,waste utilization,energy and economic security,and fuel pluralism.Based on the understanding of molecular structure effects of biofuels on soot formation and particles morphology,the effects of alcohols,ethers,esters and biodiesel on spray and combustion process in constant volume bomb in recent years are retrospectively analyzed in this paper.For the mixture,macromolecular ester fuels and polyoxymethylene dimethyl ether(PODE)are conducive to the improvement of liquid spray,while biodiesel,small molecules,dimethyl ether(DME)and alcohols are reversed.Alcohols are advantageous to the extension of mixing time and the increasing of vapor-phase mixture.Through the influence integrated assessment,alcohols show the best performance on the spray,atomization and combustion,while biodiesels show the worst.But in terms of combustion,PODE is the best choice without considering spray and atomization.For binary alternative-diesel fuel blends,methanol or butanol is the best additive based on synthetically considerations on spray,atomization and combustion.To meet the requirements of the fuel application of diesel engine,ternary fuel or even quaternary fuel have been proposed and explored.This review can help to form a systematic understanding on fuel recombining and obtain the guide of clean and efficient fuel formulation for diesel engine.
基金financially supported by the National Natural Science Foundation of China (22071137)the Program for Tsingtao Al-ion Power and Energy-storage Battery Research Team in the University (17-2-1-1-zhc)。
文摘The direct electrochemical synthesis of H_(2)O_(2)from O_(2)is currently the most promising alternative to energyintensive industrial anthraquinone oxidation/reduction methods. However, its widespread use is hampered by the lack of efficient low-cost electrocatalysts. In the current study,oxygenated boron-doped carbon(O-BC) materials were realized via a green synthetic strategy involving polymer dehalogenation and employed as electrode materials for the electrochemical synthesis of H_(2)O_(2)via a 2 e-oxygen reduction.The catalytic activity of the O-BC materials was optimized through systematic variation of the boron source(H_(2)BO_(2))dosage and annealing temperature. Electrochemical measurements revealed that the optimal sample(O-BC-2-650)exhibited a selectivity of 98% for the 2 e-oxygen reduction to H2 O_(2)and an average H_(2)O_(2)production rate of412.8 mmol g_(cat)^(-1) h^(-1)in an H-type alkaline electrolyzer. Density functional theory simulations indicated that the functionalization of active B sites with one oxygen atom provides the lowest Gibbs free energy change(ΔG) of 0.03 e V for the hydrogenation of*O_(2), while functionalization with zero or two O atoms results in much larger ΔG values(0.08 and 0.10 e V,respectively). Thus, this work details a new type of green, lowcost, and metal-free electrocatalyst for H_(2)O_(2)production.
基金supported by the National Natural Science Foundation of China(Grant Nos.41827804 and 41805093)the Natural Science Foundation of Guangdong Province(China)(No.2021A1515011206)+1 种基金the State Key Laboratory of Marine Resource Utilization in the South China Sea,Hainan University(China)(No.MRUKF2023009)the State Key Laboratory of Loess and Quaternary Geology,Institute of Earth Environment,CAS(No.SKLLQG2218).
文摘Oxygenated organic molecules(OOMs)play an important role in the formation of secondary organic aerosols(SOAs),but the mixing states of OOMs are still unclear.This study investigates the mixing states of OOM-containing single particles from the measurements taken using a single particle aerosol mass spectrometer in Guangzhou,China in 2022.Generally,the particle counts of OOM particles and the mass concentration of secondary organic carbon(SOC)exhibited similar temporal trends throughout the entire year.The OOM particles were consistently enriched in secondary ions,including ^(16)O^(−),^(26)CN^(−),^(46)NO_(2)^(−),^(62)NO_(3)^(−),and ^(97)HSO_(4)^(−).In contrast,the number fractions and diurnal patterns of OOM particles among the total detected particles showed similar distributions in August and October;however,the SOC ratios in fine particulate matter were quite different,suggesting that there were different mixing states of single-particle oxygenated organics.In addition,further classification results indicated that the OOM particles were more aged in October than August,even though the SOC ratios were higher in August.Furthermore,the distribution of hydrocarbon fragments exhibited a notable decrease from January to October,emphasizing the more aged state of the organics in October.In addition,the sharp increase in elemental carbon(EC)-OOM particles in the afternoon in October suggests the potential role of EC in the aging process of organics.Overall,in contrast to the bulk analysis of SOC mass concentration,the mixing states of the OOM particles provide insights into the formation process of SOAs in field studies.
基金the National High Technology Research and Development Program of China(863 Program)(Grant No.2006AA06A305)the National Natural Science Foundation of China(Grant No.20807025)。
文摘Oxygenated fuels are known to reduce particulate matter(PM)emissions from diesel engines.In this study,100%soy methyl ester(SME)biodiesel fuel(B100)and a blend of 10%acetal denoted by A-diesel with diesel fuel were tested as oxygenated fuels.Particle size and number distributions from a diesel engine fueled with oxygenated fuels and base diesel fuel were measured using an Electrical Low Pressure Impactor(ELPI).Measurements were made at ten steady-state operational modes of various loads at two engine speeds.It was found that the geometric mean diameters of particles from SME and Adiesel were lower than that from base diesel fuel.Compared to diesel fuel,SME emitted more ultra-fine particles at rated speed while emitting less ultra-fine particles at maximum speed.Ultra-fine particle number concentrations of A-diesel were much higher than those of base diesel fuel at most test modes.
基金supported by the National Natural Science Foundation of China,Nos.82172196(to KX),82372507(to KX)the Natural Science Foundation of Hunan Province,China,No.2023JJ40804(to QZ)the Key Laboratory of Emergency and Trauma(Hainan Medical University)of the Ministry of Education,China,No.KLET-202210(to QZ)。
文摘Ischemia–reperfusion injury is a common pathophysiological mechanism in retinal degeneration.PANoptosis is a newly defined integral form of regulated cell death that combines the key features of pyroptosis,apoptosis,and necroptosis.Oligomerization of mitochondrial voltage-dependent anion channel 1 is an important pathological event in regulating cell death in retinal ischemia–reperfusion injury.However,its role in PANoptosis remains largely unknown.In this study,we demonstrated that voltage-dependent anion channel 1 oligomerization-mediated mitochondrial dysfunction was associated with PANoptosis in retinal ischemia–reperfusion injury.Inhibition of voltage-dependent anion channel 1 oligomerization suppressed mitochondrial dysfunction and PANoptosis in retinal cells subjected to ischemia–reperfusion injury.Mechanistically,mitochondria-derived reactive oxygen species played a central role in the voltagedependent anion channel 1-mediated regulation of PANoptosis by promoting PANoptosome assembly.Moreover,inhibiting voltage-dependent anion channel 1 oligomerization protected against PANoptosis in the retinas of rats subjected to ischemia–reperfusion injury.Overall,our findings reveal the critical role of voltage-dependent anion channel 1 oligomerization in regulating PANoptosis in retinal ischemia–reperfusion injury,highlighting voltage-dependent anion channel 1 as a promising therapeutic target.
