Pre-chamber ignition technology can address the issue of uneven in-cylinder mixture combustion in large-bore marine engines.The impact of various pre-chamber structures on the formation of the mixture and jet flames w...Pre-chamber ignition technology can address the issue of uneven in-cylinder mixture combustion in large-bore marine engines.The impact of various pre-chamber structures on the formation of the mixture and jet flames within the pre-chamber is explored.This study performed numerical simulations on a large-bore marine ammonia/hydrogen pre-chamber engine prototype,considering pre-chamber volume,throat diameter,the distance between the hydrogen injector and the spark plug,and the hydrogen injector angle.Compared with the original engine,when the pre-chamber volume is 73.4 ml,the throat diameter is 14 mm,the distance ratio is 0.92,and the hydrogen injector angle is 80°.Moreover,the peak pressure in the pre-chamber increased by 23.1%,and that in the main chamber increased by 46.3%.The results indicate that the performance of the original engine is greatly enhanced by altering its fuel and pre-chamber structure.展开更多
BACKGROUND Paternal perinatal depression(PPD)is closely associated with maternal mental health challenges,marital strain,and adverse child developmental outcomes.Despite its significant impact,PPD remains under-recogn...BACKGROUND Paternal perinatal depression(PPD)is closely associated with maternal mental health challenges,marital strain,and adverse child developmental outcomes.Despite its significant impact,PPD remains under-recognized in family-centered clinical practice.Concurrently,against the backdrop of rising rates of delayed marriage and China’s Maternity Incentive Policy,the proportion of women giving birth at an advanced maternal age is increasing.Nevertheless,research specifically examining PPD among spouses of older mothers remains critically scarce,both in China and globally.AIM To investigate PPD and its influencing factors in Chinese advanced maternal age families.METHODS This cross-sectional study included 358 participants;it was conducted among fathers of pregnant women of advanced maternal age at five hospitals in the Pearl River Delta region of China from September 2023 to June 2024.Data were collected via a general information questionnaire,the Social Support Rating Scale,and the Edinburgh Postnatal Depression Scale.Latent profile analysis and regression mixture models(RMMs)were adopted to analyze the latent PPD types and factors that influenced PPD.RESULTS The incidence of PPD was 16.48%,and three profiles were identified:Low-symptomatic(175 cases,48.89%),monophasic(140 cases,39.10%),and high-symptomatic(43 cases,12.01%).The RMM analysis revealed that first pregnancy,low income(<¥3000/month),part-time work,and a history of abnormal pregnancy were positively associated with the high-symptomatic type(P<0.05).Conversely,high subjective support and support utilization were negatively associated with the high-symptomatic type compared with the low-symptomatic type(P<0.05).Good couple relationships,high objective and subjective support,and high support utilization were negatively associated with monophasic disorder(P<0.05).CONCLUSION PPD incidence is high among Chinese fathers with advanced maternal age partners,and the characteristics of depression are varied.Healthcare practitioners should prioritize individuals with low levels of social support.展开更多
Understanding the mechanisms of gas transport and the resulting preferential pathways formation through bentonite-based barriers is essential for their performance evaluation.In this experimental study,gas migration w...Understanding the mechanisms of gas transport and the resulting preferential pathways formation through bentonite-based barriers is essential for their performance evaluation.In this experimental study,gas migration within a heterogenous mixture of MX80 bentonite pellets and powder with a ratio of 80/20 in dry mass was investigated.A novel X-ray transparent constant volume cell has been developed to assess the effect of gas pressure,material heterogeneities,and water vapor gas saturation on breakthrough pressure and gas pathways.The new cell allows to perform high-resolution X-ray computed micro-tomography(X-ray μCT)scans to track microstructural changes during different phases of saturation and gas injection.Experimental results showed that the gas breakthrough occurred when the pressure was raised to 3 MPa.This is slightly higher than the expected swelling pressure(2.9 MPa)of the bentonite sample.Each gas injection was followed by a long resaturation phase restoring material homogeneity at μCT resolution scale(16 mm).However,the elapsed time needed for gas to breakthrough at 3 MPa diminished at each subsequent injection test.X-ray μCT results also revealed the opening of the specimen/cell wall interface during gas passage.This opening expanded as the injection pressure increased.The gas flow along the interface was associated with the development of dilatant pathways inside the sample,although they did not reach the outlet surface.It was observed that the water vapor gas saturation had no effect on the breakthrough pressure.These findings enhance the understanding of the complex mechanisms underlying microstructural evolution and gas pathway development within the highly heterogeneous mixture.The experimental outcomes highlight the effectiveness of X-ray μCT to improve quality protocols for engineering design and safety assessments of engineered barriers.展开更多
As the first gold mine discovered at the sea in China and the only coastal gold mine currently mined there,Sanshandao Gold Mine faces unique challenges.The mine's safety is under continual threat from its faulted ...As the first gold mine discovered at the sea in China and the only coastal gold mine currently mined there,Sanshandao Gold Mine faces unique challenges.The mine's safety is under continual threat from its faulted structure coupled with the overlying water.As the mining proceeds deeper,the risk of water inrush increases.The mine's maximum water yield reaches 15000 m3/day,which is attributable to water channels present in fault zones.Predominantly composed of soil–rock mixtures(SRM),these fault zones'seepage characteristics significantly impact water inrush risk.Consequently,investigating the seepage characteristics of SRM is of paramount importance.However,the existing literature mostly concentrates on a single stress state.Therefore,this study examined the characteristics of the permeability coefficient under three distinct stress states:osmotic,osmotic–uniaxial,and osmotic–triaxial pressure.The SRM samples utilized in this study were extracted from in situ fault zones and then reshaped in the laboratory.In addition,the micromechanical properties of the SRM samples were analyzed using computed tomography scanning.The findings reveal that the permeability coefficient is the highest under osmotic pressure and lowest under osmotic–triaxial pressure.The sensitivity coefficient shows a higher value when the rock block percentage ranges between 30%and 40%,but it falls below 1.0 when this percentage exceeds 50%under no confining pressure.Notably,rock block percentages of 40%and 60%represent the two peak points of the sensitivity coefficient under osmotic–triaxial pressure.However,SRM samples with a 40%rock block percentage consistently show the lowest permeability coefficient under all stress states.This study establishes that a power function can model the relationship between the permeability coefficient and osmotic pressure,while its relationship with axial pressure can be described using an exponential function.These insights are invaluable for developing water inrush prevention and control strategies in mining environments.展开更多
Catalytic destruction is an ascendant technology for the abatement of volatile organic compounds(VOCs)originating fromsolvent-based industrial processes.The varied composition tends to influence each VOC’s catalytic ...Catalytic destruction is an ascendant technology for the abatement of volatile organic compounds(VOCs)originating fromsolvent-based industrial processes.The varied composition tends to influence each VOC’s catalytic behavior in the reaction mixture.We investigated the catalytic destruction of multi-component VOCs including dichloromethane(DCM)and ethyl acetate(EA),as representatives from pharmaceutical waste gases,over co-supported HxPO_(4)-RuOx/CeO_(2) catalyst.A mutual inhibitory effect relating to concentrations because of competitive adsorption was verified in the binary VOCs oxidation and EA posed a more negative effect on DCM oxidation owing to EA’s superior adsorption capacity.Preferential adsorption of EA on acidic sites(HxPO_(4)/CeO_(2))promoted DCM activation on basic sites(O^(2−))and the dominating EA oxidation blocked DCM’s access to oxidation centers(RuOx/CeO_(2)),resulting in boosted monochloromethane yield and increased chlorine deposition for DCM oxidation.The impaired redox ability of Ru species owing to chlorine deposition in turn jeopardized deep oxidation of EA and its by-products,leading to increased gaseous by-products such as acetic acid originating fromEA pyrolysis.Notably,DCM at low concentration slightly promoted EA conversion at low temperatures with or without water,consistent with the enhanced EA adsorption in co-adsorption analyses.This was mainly due to that DCM impeded the shielding effect of hydrolysate deposition from rapid EA hydrolysis depending on the decreased acidity.Moreover,water benefited EA hydrolysis but decreased CO_(2) selectivity while the generated water derived from EA was likely to affect DCM transformation.This work may provide theoretical guidance for the promotion of applied catalysts toward industrial applications.展开更多
[Objectives]To optimize the optimal extraction process of Qingdu Jianpi Mixture.[Methods]Taking water addition ratio,extraction time and extraction times as process investigation factors,psoralen content,astilbin cont...[Objectives]To optimize the optimal extraction process of Qingdu Jianpi Mixture.[Methods]Taking water addition ratio,extraction time and extraction times as process investigation factors,psoralen content,astilbin content and dry extract yield as evaluation indicators,the main influencing factors and level range of the extraction process of Qingdu Jianpi Mixture were determined on the basis of single factor test method,and the optimal weight coefficient was screened by AHP-entropy method mixed with weighting method.Combined with L_(9)(3^(4))orthogonal experiment,the best extraction process was obtained.At the same time,thin-layer chromatographic identification was used to identify Ficus simplicissima Lour.and Smilax glabra Roxb.in the medicinal liquid.[Results]The best extraction process:add 1:12 water to the prescription decoction pieces,extract under reflux for 2 times,1.5 h per time,and combine the filtrate to 250 mL.Thin layer chromatography analysis showed that the spots of Ficus simplicissima Lour.and Smilax glabra Roxb.in the medicinal solution were the same as those of reference substances at the corresponding positions,and the negative control had no interference.[Conclusions]The experimental method is reasonable and feasible,and the process is reliable,which can provide experimental reference for the subsequent application of in-hospital preparations and research and development of Qingdu Jianpi Mixture.展开更多
Arsenic(As)and chromium(Cr)are two harmful toxicants as well as carcinogens which can coexist in polluted surface water and groundwater.This coexistence leads to mixture effects in animals including fish.Both of these...Arsenic(As)and chromium(Cr)are two harmful toxicants as well as carcinogens which can coexist in polluted surface water and groundwater.This coexistence leads to mixture effects in animals including fish.Both of these heavy metals are reported to manifest reactive oxygen species(ROS)mediated toxicity.Though individual neurotoxic effects have been reported,their mixture effects,its mechanism and cellular responses against oxidative stress and DNA damages remain unknown.The present study evaluated the individual and mixture effects of As and Cr at their environmentally relevant concentrations in zebrafish(Danio rerio)brain after 15,30 and 60 days of exposure.Nrf2,a transcription factor is involved in the expressional regulation of enzymes needed to maintain cellular redox homeostasis.This study reported the expressional pattern of Nrf2 and its associated xenobiotic metabolizing enzyme Nqo1 and other markers of oxidative stress such as ROS generation,reduced glutathione level,lipid peroxidation and catalase activity.Increased malondialdehyde(MDA)content,glutathione level,and catalase activity indicated oxidative stress in exposed groups.In addition,this study revealed expressional alterations of neurotoxicity marker(ache),DNA repair(ogg1,apex1,creb1,polb,mlh1,msh2 and msh6)and tumor suppressor(p53,brca2)genes.Results of ROS generation,MDA level,histopathological analysis,gene expression and immunofluorescence study confirmed that As and Cr did not show antagonistic effects in combination rather indicated additive effects which was dose-dependent but not always linear.展开更多
Compacted sand-bentonite mixtures are used as waste containment barriers(e.g.landfill liners and bentonite buffers for nuclear waste)to restrict contaminant transport.The potential for enhanced chemical containment of...Compacted sand-bentonite mixtures are used as waste containment barriers(e.g.landfill liners and bentonite buffers for nuclear waste)to restrict contaminant transport.The potential for enhanced chemical containment of compacted sand-bentonite mixtures due to semipermeable membrane behavior has also been demonstrated.However,the extent to which membrane behavior persists in the presence of highly concentrated chemical solutions,which have been shown to degrade membrane behavior in bentonite-based barriers,remains largely unknown.Moreover,the limiting(threshold)salt concentrations at which membrane behavior of compacted sand-bentonite mixtures is effectively destroyed have not been evaluated.Accordingly,this study quantified the limiting membrane behavior of two duplicated specimens of compacted sand-bentonite mixture comprising 15%sodium bentonite(by dry mass)by determining the limiting salt concentrations at which measurable membrane behavior was eliminated.The specimens were exposed to increasingly higher source concentrations,Cot,of boundary monovalent salt solutions(KCl and NaCl)until measured values of the membrane efficiency coefficient,ω,were effectively zero.Overall,ωdecreased from an average of 0.032 to zero as Cot increased from 160 mmol/L KCl to 3.27 mol/L NaCl,resulting in limiting threshold salt concentrations for the two tests between 1.63 mol/L and 3.27 mol/L NaCl,which are significantly higher than those at which measurable membrane behavior has previously been demonstrated.展开更多
Density(p),speed of sound(u),viscosity(η),and refractive index(n_(D))were measured for pure acetonitrile,trichloroethene,and tetrachloroethene,as well as their binary mixtures at temperatures T=(293.15,298.15,303.15)...Density(p),speed of sound(u),viscosity(η),and refractive index(n_(D))were measured for pure acetonitrile,trichloroethene,and tetrachloroethene,as well as their binary mixtures at temperatures T=(293.15,298.15,303.15)K and at ambient pressure(81.5 kPa).From the experimental data,excess molar volume(V_(m)~E),thermal expansion coefficients(α),deviations in isentropic compressibility(Δκ_(S)),viscosity(Δ_η),and refractive index(Δn_(D))were calculated.These values were then correlated using the Redlich-Kister polynomial equation,with fitting coefficients and standard deviations determined.Additionally,the Prigogine-Flory-Patterson(PFP)theory and the Extended Real Associated Solution(ERAS)model were employed to correlate the excess molar volume,while the Perturbed Chain Statistical Associating Fluid Theory(PC-SAFT)was used to predict the density of mixtures.展开更多
This study aimed to identify the worst“bad actors”in mixtures of pollutants contributing to liver damage and shorter telomeres in the U.S.population,using weighted quantile sum(WQS)modeling with stratification by ra...This study aimed to identify the worst“bad actors”in mixtures of pollutants contributing to liver damage and shorter telomeres in the U.S.population,using weighted quantile sum(WQS)modeling with stratification by race/ethnicity.We conducted a comprehensive cross-sectional analysis of mixtures of pollutants in National Health and Nutrition Examination Survey datasets:(1)33,979 adults with blood levels of cadmium(Cd),lead(Pb),and mercury,including subsets with measurements of per-/polyfluoroalkyl substances(PFAS),and polychlorinated biphenyls(PCBs)/polychlorinated dibenzo-p-dioxins and dibenzofurans(PCDD/Fs);and(2)7360 adults with measurements of telomeres,Cd,and Pb.Multivariable-adjusted WQS regression examined associations between WQS mixture indices and liver injury(alanine aminotransferase(ALT)-elevation),advanced liverfibrosis(LF),and telomere length.WQSmetal indices were associated with advanced-LF in all racial/ethnic groups.The top contributor was Cd in the total population and in non-Hispanic Whites(NHW),while Pb was the top contributor in non-Hispanic Blacks(NHB).The WQSmetal-PCB-PCDD/F index was associated with ALT-elevation,with PCB126,Cd and Pb as main contributors;the odds ratio(OR)per decile was 1.50(95%CI,1.26–1.78),while the OR per decile of the WQSmetal-PFAS index was 1.03(95%CI,0.98–1.05),not significant.WQS_(metal indices)were associated with shorter telomeres.Cd was main contributor associated with advanced-LF in NHW,while Pb was the major bad actor in NHB,suggesting that NHB may be especially susceptible to Pb toxicity.Metals were associated with shorter telomeres.Metal and PCB/PCDD/F mixtures were associated with ALT-elevation.Heavy metals and organic chemicals may contribute to liver-related morbidity and healthcare disparities.展开更多
Compacted clays are widely used as barriers in municipal solid waste(MSW)landfills due to their low permeability,and the hydro-mechanical behaviour of such materials can be greatly affected by environmental conditions...Compacted clays are widely used as barriers in municipal solid waste(MSW)landfills due to their low permeability,and the hydro-mechanical behaviour of such materials can be greatly affected by environmental conditions.In this study,a series of wetting-drying(W-D)cycle tests and hydraulic conductivity tests were conducted on compacted red clay-bentonite mixtures.Various concentrations of NaCl solution were introduced during wetting to investigate the chemical effects.Scanning electron microscopy(SEM)and mercury intrusion porosimetry(MIP)tests were performed to analyze the evolution of soil microstructure.Results indicate that the compacted mixtures undergo cumulative shrinkage during W-D cycles,reaching an elastic state after three cycles.The hydraulic conductivity decreases as the bentonite content increases,becoming lower than 1×10^(-9)m/s when the bentonite content exceeds 10%,which satisfies the requirement for waste barriers.For a given bentonite content,the relationship between the logarithm of hydraulic conductivity and the void ratio can be well described by a linear regression equation.Additionally,the hydraulic conductivity initially increases and then decreases during the W-D cycles,peaking during the second wetting process.The presence of NaCl solution accelerates microstructural evolution and cumulative shrinkage,particularly in pure red clay.Therefore,adding an appropriate amount of bentonite mitigates the effect of NaCl solution on the volume change.Furthermore,the addition of bentonite exhibits a dual effect:the lubrication effect dominates in the mixtures with low bentonite content,while the filling effect prevails as volume change decreases due to the restriction of aggregates rearrangement when the bentonite content is high enough to fill the macropores.展开更多
Objective Humans are exposed to complex mixtures of environmental chemicals and other factors that can affect their health.Analysis of these mixture exposures presents several key challenges for environmental epidemio...Objective Humans are exposed to complex mixtures of environmental chemicals and other factors that can affect their health.Analysis of these mixture exposures presents several key challenges for environmental epidemiology and risk assessment,including high dimensionality,correlated exposure,and subtle individual effects.Methods We proposed a novel statistical approach,the generalized functional linear model(GFLM),to analyze the health effects of exposure mixtures.GFLM treats the effect of mixture exposures as a smooth function by reordering exposures based on specific mechanisms and capturing internal correlations to provide a meaningful estimation and interpretation.The robustness and efficiency was evaluated under various scenarios through extensive simulation studies.Results We applied the GFLM to two datasets from the National Health and Nutrition Examination Survey(NHANES).In the first application,we examined the effects of 37 nutrients on BMI(2011–2016 cycles).The GFLM identified a significant mixture effect,with fiber and fat emerging as the nutrients with the greatest negative and positive effects on BMI,respectively.For the second application,we investigated the association between four pre-and perfluoroalkyl substances(PFAS)and gout risk(2007–2018 cycles).Unlike traditional methods,the GFLM indicated no significant association,demonstrating its robustness to multicollinearity.Conclusion GFLM framework is a powerful tool for mixture exposure analysis,offering improved handling of correlated exposures and interpretable results.It demonstrates robust performance across various scenarios and real-world applications,advancing our understanding of complex environmental exposures and their health impacts on environmental epidemiology and toxicology.展开更多
The article considers a relaxation of the water/polypropylene glycol-425 solution with a lower critical solution temperature(LCST)following its pulsed superheating concerning liquid-liquid and liquid-vapor equilibrium...The article considers a relaxation of the water/polypropylene glycol-425 solution with a lower critical solution temperature(LCST)following its pulsed superheating concerning liquid-liquid and liquid-vapor equilibrium lines,as well as the liquid-liquid spinodal.Superheating was performed using the pulsed heat generation method in a micro-sized wire probe.The main heating mode was the constant(over the pulse length)power mode.Characteristic heating rates ranged from 0.05×10^(5) to 2×10^(5) K/s,while the degree of superheating concerning the spinodal was up to 200 K.The temperature of spontaneous boiling-up and the amplitude of the corresponding signal were monitored as functions of the heating rate set by the power value.The results demonstrate an example of the interaction of liquidliquid and liquid-vapor phase transitions,as well as the spinodal decomposition of a solution with LCST against the background of its unstable states.We proposed a physical model to explain the minimum spontaneous boiling-up temperature revealed within a certain range of heating rates,which is not typical of completely miscible solutions.Further research will focus on establishing a general criterion for the possibility of spinodal decomposition of such solutions under the conditions of rapid heating.展开更多
The use of hot recycled asphalt mixture(HRAM)allows for a reduction in the depletion of non-renewable resources and presents environmental benefits.However,concerns arise regarding the performance of HRAM due to the l...The use of hot recycled asphalt mixture(HRAM)allows for a reduction in the depletion of non-renewable resources and presents environmental benefits.However,concerns arise regarding the performance of HRAM due to the lower degree of blending(DOB)of virgin and aged asphalt(V&A asphalt).This paper aims to provide an up-to-date review on the DOB of V&A asphalt in HRAM.Initially,the paper introduces the DOB of V&A asphalt,followed by an analysis of the blending theory,evaluation methods,and influencing factors of DOB.Subsequently,the effect of DOB on the performance of HRAM is investigated,and molecular dynamic simulation is utilized to analyze the blend of V&A asphalt.Finally,methods for improving DOB are summarized.It was found that the use of high-resolution microscopy with tracer methods such as SEM/EDS was an effective way to characterize DOB.Furthermore,the chemical composition and colloid structure between virgin and aged asphalt are crucial to DOB.Additionally,improving DOB by utilizing the coupling effect of time and temperature during transportation,paving,and compaction stages is promising.Future research should focus on standardizing test methods,refining field simulation models,and developing intelligent construction technologies to achieve more efficient and durable blending.This review provides theoretical guidance and practical references for improving the DOB of V&A asphalt and promoting sustainable pavement construction.展开更多
Suffusion is the process defined as the migration of relatively small soil particles through the pores of a soil matrix composed of relatively large particles,driven by substantial hydrodynamic forces and weak attract...Suffusion is the process defined as the migration of relatively small soil particles through the pores of a soil matrix composed of relatively large particles,driven by substantial hydrodynamic forces and weak attraction energies.This study investigates the influence of flow direction(upward and downward)on suffusion induced by interaction energies in sand-clay mixtures under both saturated and unsaturated conditions.The impact of clay mineralogy(kaolinite,illite,and montmorillonite),sand-grain size,and ionic concentration(IC)gradient were discussed based on the observed breakthrough curves(BTCs)and relative saturation rate(Sr)during injection(particularly for unsaturated conditions).Under saturated conditions,higher susceptibility to suffusion was observed in sand-kaolinite and sand-illite mixtures under downward flow compared to upward flow,whereas the suffusion of montmorillonite was more significant under upward flow than under downward flow.In contrast,for unsaturated conditions,more substantial suffusion of kaolinite and illite particles occurred under upward flow compared to downward flow,whereas the opposite trend was observed in sand-montmorillonite mixtures.In addition,the impact of sand-grain size(or the size ratio between sand and clay)on the suffusion of kaolinite and illite under unsaturated conditions suggests a reduced size ratio that leads to relatively significant suffusion under downward flow compared to upward flow.The findings presented in this study contribute to a comprehensive understanding of the influence of flow direction on suffusion in sand-clay mixtures under both saturated and unsaturated conditions.展开更多
Gaze estimation,a crucial non-verbal communication cue,has achieved remarkable progress through convolutional neural networks.However,accurate gaze prediction in uncon-strained environments,particularly in extreme hea...Gaze estimation,a crucial non-verbal communication cue,has achieved remarkable progress through convolutional neural networks.However,accurate gaze prediction in uncon-strained environments,particularly in extreme head poses,partial occlusions,and abnormal lighting,remains challenging.Existing models often struggle to effectively focus on discriminative ocular features,leading to suboptimal performance.To address these limitations,this paper proposes dual-branch gaze estimation with Gaussian mixture distribution heatmaps and dynamic adaptive loss function(DMGDL),a novel dual-branch gaze estimation algorithm.By introducing Gaussian mixture distribution heatmaps centered on pupil positions as spatial attention guides,the model is enabled to prioritize ocular regions.Additionally,a dual-branch network architecture is designed to separately extract features for yaw and pitch angles,enhancing flexibility and mitigating cross-angle interference.A dynamic adaptive loss function is further formulated to address discontinuities in angle estimation,improving robustness and convergence stability.Experimental evaluations on three benchmark datasets demonstrate that DMGDL outperforms state-of-the-art methods,achiev-ing a mean angular error of 3.98°on the Max-Planck institute for informatics face gaze(MPI-IFaceGaze)dataset,10.21°on the physically unconstrained gaze estimation in the wild(Gaze360)dataset and 6.14°on the real-time eye gaze estimation in natural environments(RT-Gene)dataset,exhibiting superior generalization and robustness.展开更多
The upper bound on the model error will be decreased when the mean square error and the maximum distance deviation are sufficiently small in the uniform designs for mixture experiments and the design is more robust fo...The upper bound on the model error will be decreased when the mean square error and the maximum distance deviation are sufficiently small in the uniform designs for mixture experiments and the design is more robust for the model.However,the analytical expressions of MSED and MD are currently only available in the hypercube,but both types of deviations in other studies are just approximations.Although it can obtain good approximations in the low-dimensional case,the calculation will be more complicated for an experiment with more variables.Therefore,in this paper,an algorithm based on lattice point partitioning design is proposed to obtain the analytical expression of the MSED and MD in the region covered by the lattice points.Furthermore,the design’s optimality is considered and illustrated by examples under the same uniformity.展开更多
The Russian energy sector remains heavily reliant on thermal power plants,with gas generation accounting for approximately 66%of the installed capacity.However,the industry faces challenges such as depletion of reserv...The Russian energy sector remains heavily reliant on thermal power plants,with gas generation accounting for approximately 66%of the installed capacity.However,the industry faces challenges such as depletion of reserves,rising prices for hydrocarbons,and increasing concentrations of carbon dioxide in the atmosphere.This study focuses on developing new scientific and technical solutions to increase the efficiency and environmental safety of combined cycle power units.The research involves structural and parametric optimization of trinary cycle power plants operating on a methane-hydrogen mixture,as well as the development and optimization of turbine and heat exchange equipment for low-temperature power plants.The results show that the transition to trinary CCGT(Combine Cycle Gas Turbine)units with deep utilization and the use of hydrogen fuel can significantly reduce specific CO_(2) emissions and increase energy efficiency up to 0.21%with also increases in capacity of turbine of approximately 17 MW.The aim of this research is to calculate the efficiency,cost effectiveness and environmental-friendly solution for power generation using mixture of hydrogen-methane as fuel in combine cycle power plant that includes ORC.Additionally,the efficiency of the organic Rankine Cycle(ORC)benefits from the increased moisture,with capacity improvements of 1–2 MW observed when the hydrogen proportion rises from 25%to 50%.Moreover,the potential for zero emissions,coupled with significant increases in power output and efficiency,underscores hydrogen’s role as a pivotal component in the future of energy production.展开更多
The computational accuracy and efficiency of modeling the stress spectrum derived from bridge monitoring data significantly influence the fatigue life assessment of steel bridges.Therefore,determining the optimal stre...The computational accuracy and efficiency of modeling the stress spectrum derived from bridge monitoring data significantly influence the fatigue life assessment of steel bridges.Therefore,determining the optimal stress spectrum model is crucial for further fatigue reliability analysis.This study investigates the performance of the REBMIX algorithm in modeling both univariate(stress range)and multivariate(stress range and mean stress)distributions of the rain-flowmatrix for a steel arch bridge,usingAkaike’s Information Criterion(AIC)as a performance metric.Four types of finitemixture distributions—Normal,Lognormal,Weibull,and Gamma—are employed tomodel the stress range.Additionally,mixed distributions,including Normal-Normal,Lognormal-Normal,Weibull-Normal,and Gamma-Normal,are utilized to model the joint distribution of stress range and mean stress.The REBMIX algorithm estimates the number of components,component weights,and component parameters for each candidate finite mixture distribution.The results demonstrate that the REBMIX algorithm-based mixture parameter estimation approach effectively identifies the optimal distribution based on AIC values.Furthermore,the algorithm exhibits superior computational efficiency compared to traditional methods,making it highly suitable for practical applications.展开更多
基金Supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions under Grant No.014000319/2018-00391.
文摘Pre-chamber ignition technology can address the issue of uneven in-cylinder mixture combustion in large-bore marine engines.The impact of various pre-chamber structures on the formation of the mixture and jet flames within the pre-chamber is explored.This study performed numerical simulations on a large-bore marine ammonia/hydrogen pre-chamber engine prototype,considering pre-chamber volume,throat diameter,the distance between the hydrogen injector and the spark plug,and the hydrogen injector angle.Compared with the original engine,when the pre-chamber volume is 73.4 ml,the throat diameter is 14 mm,the distance ratio is 0.92,and the hydrogen injector angle is 80°.Moreover,the peak pressure in the pre-chamber increased by 23.1%,and that in the main chamber increased by 46.3%.The results indicate that the performance of the original engine is greatly enhanced by altering its fuel and pre-chamber structure.
基金Supported by High-level Professional Groups in Gangdong Province,No.GSPZYQ2020101Guangdong Province Educational Research Planning Project,No.2024GXJK742。
文摘BACKGROUND Paternal perinatal depression(PPD)is closely associated with maternal mental health challenges,marital strain,and adverse child developmental outcomes.Despite its significant impact,PPD remains under-recognized in family-centered clinical practice.Concurrently,against the backdrop of rising rates of delayed marriage and China’s Maternity Incentive Policy,the proportion of women giving birth at an advanced maternal age is increasing.Nevertheless,research specifically examining PPD among spouses of older mothers remains critically scarce,both in China and globally.AIM To investigate PPD and its influencing factors in Chinese advanced maternal age families.METHODS This cross-sectional study included 358 participants;it was conducted among fathers of pregnant women of advanced maternal age at five hospitals in the Pearl River Delta region of China from September 2023 to June 2024.Data were collected via a general information questionnaire,the Social Support Rating Scale,and the Edinburgh Postnatal Depression Scale.Latent profile analysis and regression mixture models(RMMs)were adopted to analyze the latent PPD types and factors that influenced PPD.RESULTS The incidence of PPD was 16.48%,and three profiles were identified:Low-symptomatic(175 cases,48.89%),monophasic(140 cases,39.10%),and high-symptomatic(43 cases,12.01%).The RMM analysis revealed that first pregnancy,low income(<¥3000/month),part-time work,and a history of abnormal pregnancy were positively associated with the high-symptomatic type(P<0.05).Conversely,high subjective support and support utilization were negatively associated with the high-symptomatic type compared with the low-symptomatic type(P<0.05).Good couple relationships,high objective and subjective support,and high support utilization were negatively associated with monophasic disorder(P<0.05).CONCLUSION PPD incidence is high among Chinese fathers with advanced maternal age partners,and the characteristics of depression are varied.Healthcare practitioners should prioritize individuals with low levels of social support.
基金funding from the European Union's Horizon 2020 research and innovation program European Joint Program on RadioactiveWaste Management(EURAD)(2019e2024)WP-Gas‘Mechanistic understanding of gas transport in clay materials’under Grant agreement No.847593.
文摘Understanding the mechanisms of gas transport and the resulting preferential pathways formation through bentonite-based barriers is essential for their performance evaluation.In this experimental study,gas migration within a heterogenous mixture of MX80 bentonite pellets and powder with a ratio of 80/20 in dry mass was investigated.A novel X-ray transparent constant volume cell has been developed to assess the effect of gas pressure,material heterogeneities,and water vapor gas saturation on breakthrough pressure and gas pathways.The new cell allows to perform high-resolution X-ray computed micro-tomography(X-ray μCT)scans to track microstructural changes during different phases of saturation and gas injection.Experimental results showed that the gas breakthrough occurred when the pressure was raised to 3 MPa.This is slightly higher than the expected swelling pressure(2.9 MPa)of the bentonite sample.Each gas injection was followed by a long resaturation phase restoring material homogeneity at μCT resolution scale(16 mm).However,the elapsed time needed for gas to breakthrough at 3 MPa diminished at each subsequent injection test.X-ray μCT results also revealed the opening of the specimen/cell wall interface during gas passage.This opening expanded as the injection pressure increased.The gas flow along the interface was associated with the development of dilatant pathways inside the sample,although they did not reach the outlet surface.It was observed that the water vapor gas saturation had no effect on the breakthrough pressure.These findings enhance the understanding of the complex mechanisms underlying microstructural evolution and gas pathway development within the highly heterogeneous mixture.The experimental outcomes highlight the effectiveness of X-ray μCT to improve quality protocols for engineering design and safety assessments of engineered barriers.
基金State Key Research Development Program of China,Grant/Award Number:2021YFC3001301。
文摘As the first gold mine discovered at the sea in China and the only coastal gold mine currently mined there,Sanshandao Gold Mine faces unique challenges.The mine's safety is under continual threat from its faulted structure coupled with the overlying water.As the mining proceeds deeper,the risk of water inrush increases.The mine's maximum water yield reaches 15000 m3/day,which is attributable to water channels present in fault zones.Predominantly composed of soil–rock mixtures(SRM),these fault zones'seepage characteristics significantly impact water inrush risk.Consequently,investigating the seepage characteristics of SRM is of paramount importance.However,the existing literature mostly concentrates on a single stress state.Therefore,this study examined the characteristics of the permeability coefficient under three distinct stress states:osmotic,osmotic–uniaxial,and osmotic–triaxial pressure.The SRM samples utilized in this study were extracted from in situ fault zones and then reshaped in the laboratory.In addition,the micromechanical properties of the SRM samples were analyzed using computed tomography scanning.The findings reveal that the permeability coefficient is the highest under osmotic pressure and lowest under osmotic–triaxial pressure.The sensitivity coefficient shows a higher value when the rock block percentage ranges between 30%and 40%,but it falls below 1.0 when this percentage exceeds 50%under no confining pressure.Notably,rock block percentages of 40%and 60%represent the two peak points of the sensitivity coefficient under osmotic–triaxial pressure.However,SRM samples with a 40%rock block percentage consistently show the lowest permeability coefficient under all stress states.This study establishes that a power function can model the relationship between the permeability coefficient and osmotic pressure,while its relationship with axial pressure can be described using an exponential function.These insights are invaluable for developing water inrush prevention and control strategies in mining environments.
基金supported by the National Natural Science Foundation of China (Nos.21906087 and 52070168)the Key R&D Plan of Zhejiang Province (No.2023C03127)the Fundamental Research Funds for the Central Universities (No.226-2022-00150).
文摘Catalytic destruction is an ascendant technology for the abatement of volatile organic compounds(VOCs)originating fromsolvent-based industrial processes.The varied composition tends to influence each VOC’s catalytic behavior in the reaction mixture.We investigated the catalytic destruction of multi-component VOCs including dichloromethane(DCM)and ethyl acetate(EA),as representatives from pharmaceutical waste gases,over co-supported HxPO_(4)-RuOx/CeO_(2) catalyst.A mutual inhibitory effect relating to concentrations because of competitive adsorption was verified in the binary VOCs oxidation and EA posed a more negative effect on DCM oxidation owing to EA’s superior adsorption capacity.Preferential adsorption of EA on acidic sites(HxPO_(4)/CeO_(2))promoted DCM activation on basic sites(O^(2−))and the dominating EA oxidation blocked DCM’s access to oxidation centers(RuOx/CeO_(2)),resulting in boosted monochloromethane yield and increased chlorine deposition for DCM oxidation.The impaired redox ability of Ru species owing to chlorine deposition in turn jeopardized deep oxidation of EA and its by-products,leading to increased gaseous by-products such as acetic acid originating fromEA pyrolysis.Notably,DCM at low concentration slightly promoted EA conversion at low temperatures with or without water,consistent with the enhanced EA adsorption in co-adsorption analyses.This was mainly due to that DCM impeded the shielding effect of hydrolysate deposition from rapid EA hydrolysis depending on the decreased acidity.Moreover,water benefited EA hydrolysis but decreased CO_(2) selectivity while the generated water derived from EA was likely to affect DCM transformation.This work may provide theoretical guidance for the promotion of applied catalysts toward industrial applications.
基金Supported by Huang Ruisong's National Famous Old Traditional Chinese Medicine Expert Inheritance Studio Construction Project[GuoZhongYiYaoRenJiaoHan(2022)75]Hospital Pharmacy Research Project of Guangxi Pharmaceutical Association(GXYXH-202404)+4 种基金2024 Youth Science Fund Project of International Zhuang Medical Hospital(2024GZYJKT005)High-level Traditional Chinese Medicine Key Discipline Construction Project of National Administration of Traditional Chinese Medicine(ZYYZDXK-2023165)National Old Pharmaceutical Workers Inheritance Studio Construction Project of National Administration of Traditional Chinese Medicine[GuoZhongYiYaoRenJiaoHan(2024)255]Talent Cultivation Project-"Young Crop Project"of International Zhuang Medical Hospital Affiliated to Guangxi University of Chinese Medicine(2022001)Guangxi Traditional Chinese Medicine Multidisciplinary Innovation Team Project(GZKJ2309).
文摘[Objectives]To optimize the optimal extraction process of Qingdu Jianpi Mixture.[Methods]Taking water addition ratio,extraction time and extraction times as process investigation factors,psoralen content,astilbin content and dry extract yield as evaluation indicators,the main influencing factors and level range of the extraction process of Qingdu Jianpi Mixture were determined on the basis of single factor test method,and the optimal weight coefficient was screened by AHP-entropy method mixed with weighting method.Combined with L_(9)(3^(4))orthogonal experiment,the best extraction process was obtained.At the same time,thin-layer chromatographic identification was used to identify Ficus simplicissima Lour.and Smilax glabra Roxb.in the medicinal liquid.[Results]The best extraction process:add 1:12 water to the prescription decoction pieces,extract under reflux for 2 times,1.5 h per time,and combine the filtrate to 250 mL.Thin layer chromatography analysis showed that the spots of Ficus simplicissima Lour.and Smilax glabra Roxb.in the medicinal solution were the same as those of reference substances at the corresponding positions,and the negative control had no interference.[Conclusions]The experimental method is reasonable and feasible,and the process is reliable,which can provide experimental reference for the subsequent application of in-hospital preparations and research and development of Qingdu Jianpi Mixture.
基金the Department of Zoology,Visva-Bharati for providing infrastructural supportSreejata Kamila is grateful to the Council of Scientific and Industrial Research(CSIR),India for Senior Research Fellowship(CSIR File No.09/202(0102)/2019-EMR-I)+2 种基金Koushik Kumar Dey acknowledges the Department of Biotechnology,New Delhi for research fellowship(No.BT/PR28560/AAQ/3/919/2018)Shehnaz Islam is thankful to Maulana Azad National Fellowship(UGC ref ID-201920–345938)India for her financial support.
文摘Arsenic(As)and chromium(Cr)are two harmful toxicants as well as carcinogens which can coexist in polluted surface water and groundwater.This coexistence leads to mixture effects in animals including fish.Both of these heavy metals are reported to manifest reactive oxygen species(ROS)mediated toxicity.Though individual neurotoxic effects have been reported,their mixture effects,its mechanism and cellular responses against oxidative stress and DNA damages remain unknown.The present study evaluated the individual and mixture effects of As and Cr at their environmentally relevant concentrations in zebrafish(Danio rerio)brain after 15,30 and 60 days of exposure.Nrf2,a transcription factor is involved in the expressional regulation of enzymes needed to maintain cellular redox homeostasis.This study reported the expressional pattern of Nrf2 and its associated xenobiotic metabolizing enzyme Nqo1 and other markers of oxidative stress such as ROS generation,reduced glutathione level,lipid peroxidation and catalase activity.Increased malondialdehyde(MDA)content,glutathione level,and catalase activity indicated oxidative stress in exposed groups.In addition,this study revealed expressional alterations of neurotoxicity marker(ache),DNA repair(ogg1,apex1,creb1,polb,mlh1,msh2 and msh6)and tumor suppressor(p53,brca2)genes.Results of ROS generation,MDA level,histopathological analysis,gene expression and immunofluorescence study confirmed that As and Cr did not show antagonistic effects in combination rather indicated additive effects which was dose-dependent but not always linear.
文摘Compacted sand-bentonite mixtures are used as waste containment barriers(e.g.landfill liners and bentonite buffers for nuclear waste)to restrict contaminant transport.The potential for enhanced chemical containment of compacted sand-bentonite mixtures due to semipermeable membrane behavior has also been demonstrated.However,the extent to which membrane behavior persists in the presence of highly concentrated chemical solutions,which have been shown to degrade membrane behavior in bentonite-based barriers,remains largely unknown.Moreover,the limiting(threshold)salt concentrations at which membrane behavior of compacted sand-bentonite mixtures is effectively destroyed have not been evaluated.Accordingly,this study quantified the limiting membrane behavior of two duplicated specimens of compacted sand-bentonite mixture comprising 15%sodium bentonite(by dry mass)by determining the limiting salt concentrations at which measurable membrane behavior was eliminated.The specimens were exposed to increasingly higher source concentrations,Cot,of boundary monovalent salt solutions(KCl and NaCl)until measured values of the membrane efficiency coefficient,ω,were effectively zero.Overall,ωdecreased from an average of 0.032 to zero as Cot increased from 160 mmol/L KCl to 3.27 mol/L NaCl,resulting in limiting threshold salt concentrations for the two tests between 1.63 mol/L and 3.27 mol/L NaCl,which are significantly higher than those at which measurable membrane behavior has previously been demonstrated.
基金Bu-Ali Sina University for providing financial support for conducting this study。
文摘Density(p),speed of sound(u),viscosity(η),and refractive index(n_(D))were measured for pure acetonitrile,trichloroethene,and tetrachloroethene,as well as their binary mixtures at temperatures T=(293.15,298.15,303.15)K and at ambient pressure(81.5 kPa).From the experimental data,excess molar volume(V_(m)~E),thermal expansion coefficients(α),deviations in isentropic compressibility(Δκ_(S)),viscosity(Δ_η),and refractive index(Δn_(D))were calculated.These values were then correlated using the Redlich-Kister polynomial equation,with fitting coefficients and standard deviations determined.Additionally,the Prigogine-Flory-Patterson(PFP)theory and the Extended Real Associated Solution(ERAS)model were employed to correlate the excess molar volume,while the Perturbed Chain Statistical Associating Fluid Theory(PC-SAFT)was used to predict the density of mixtures.
基金supported by U01OH012263,and U01 OH012622 from the National Institute for Occupational Safety and HealthPCF 604934 from Prevent Cancer Foundation+1 种基金National Institutes of Health(NIH)/National Cancer Institute(NCI)1U01CA288425–0P30 ES023515 from the National Institute of Environmental Health Sciences.
文摘This study aimed to identify the worst“bad actors”in mixtures of pollutants contributing to liver damage and shorter telomeres in the U.S.population,using weighted quantile sum(WQS)modeling with stratification by race/ethnicity.We conducted a comprehensive cross-sectional analysis of mixtures of pollutants in National Health and Nutrition Examination Survey datasets:(1)33,979 adults with blood levels of cadmium(Cd),lead(Pb),and mercury,including subsets with measurements of per-/polyfluoroalkyl substances(PFAS),and polychlorinated biphenyls(PCBs)/polychlorinated dibenzo-p-dioxins and dibenzofurans(PCDD/Fs);and(2)7360 adults with measurements of telomeres,Cd,and Pb.Multivariable-adjusted WQS regression examined associations between WQS mixture indices and liver injury(alanine aminotransferase(ALT)-elevation),advanced liverfibrosis(LF),and telomere length.WQSmetal indices were associated with advanced-LF in all racial/ethnic groups.The top contributor was Cd in the total population and in non-Hispanic Whites(NHW),while Pb was the top contributor in non-Hispanic Blacks(NHB).The WQSmetal-PCB-PCDD/F index was associated with ALT-elevation,with PCB126,Cd and Pb as main contributors;the odds ratio(OR)per decile was 1.50(95%CI,1.26–1.78),while the OR per decile of the WQSmetal-PFAS index was 1.03(95%CI,0.98–1.05),not significant.WQS_(metal indices)were associated with shorter telomeres.Cd was main contributor associated with advanced-LF in NHW,while Pb was the major bad actor in NHB,suggesting that NHB may be especially susceptible to Pb toxicity.Metals were associated with shorter telomeres.Metal and PCB/PCDD/F mixtures were associated with ALT-elevation.Heavy metals and organic chemicals may contribute to liver-related morbidity and healthcare disparities.
基金the National Natural Science Foundation of China(Grant Nos.42372333 and 42072318)the China Scholarship Council(CSC)(Grant No.202306370029)。
文摘Compacted clays are widely used as barriers in municipal solid waste(MSW)landfills due to their low permeability,and the hydro-mechanical behaviour of such materials can be greatly affected by environmental conditions.In this study,a series of wetting-drying(W-D)cycle tests and hydraulic conductivity tests were conducted on compacted red clay-bentonite mixtures.Various concentrations of NaCl solution were introduced during wetting to investigate the chemical effects.Scanning electron microscopy(SEM)and mercury intrusion porosimetry(MIP)tests were performed to analyze the evolution of soil microstructure.Results indicate that the compacted mixtures undergo cumulative shrinkage during W-D cycles,reaching an elastic state after three cycles.The hydraulic conductivity decreases as the bentonite content increases,becoming lower than 1×10^(-9)m/s when the bentonite content exceeds 10%,which satisfies the requirement for waste barriers.For a given bentonite content,the relationship between the logarithm of hydraulic conductivity and the void ratio can be well described by a linear regression equation.Additionally,the hydraulic conductivity initially increases and then decreases during the W-D cycles,peaking during the second wetting process.The presence of NaCl solution accelerates microstructural evolution and cumulative shrinkage,particularly in pure red clay.Therefore,adding an appropriate amount of bentonite mitigates the effect of NaCl solution on the volume change.Furthermore,the addition of bentonite exhibits a dual effect:the lubrication effect dominates in the mixtures with low bentonite content,while the filling effect prevails as volume change decreases due to the restriction of aggregates rearrangement when the bentonite content is high enough to fill the macropores.
基金supported in part by the Young Scientists Fund of the National Natural Science Foundation of China(Grant Nos.82304253)(and 82273709)the Foundation for Young Talents in Higher Education of Guangdong Province(Grant No.2022KQNCX021)the PhD Starting Project of Guangdong Medical University(Grant No.GDMUB2022054).
文摘Objective Humans are exposed to complex mixtures of environmental chemicals and other factors that can affect their health.Analysis of these mixture exposures presents several key challenges for environmental epidemiology and risk assessment,including high dimensionality,correlated exposure,and subtle individual effects.Methods We proposed a novel statistical approach,the generalized functional linear model(GFLM),to analyze the health effects of exposure mixtures.GFLM treats the effect of mixture exposures as a smooth function by reordering exposures based on specific mechanisms and capturing internal correlations to provide a meaningful estimation and interpretation.The robustness and efficiency was evaluated under various scenarios through extensive simulation studies.Results We applied the GFLM to two datasets from the National Health and Nutrition Examination Survey(NHANES).In the first application,we examined the effects of 37 nutrients on BMI(2011–2016 cycles).The GFLM identified a significant mixture effect,with fiber and fat emerging as the nutrients with the greatest negative and positive effects on BMI,respectively.For the second application,we investigated the association between four pre-and perfluoroalkyl substances(PFAS)and gout risk(2007–2018 cycles).Unlike traditional methods,the GFLM indicated no significant association,demonstrating its robustness to multicollinearity.Conclusion GFLM framework is a powerful tool for mixture exposure analysis,offering improved handling of correlated exposures and interpretable results.It demonstrates robust performance across various scenarios and real-world applications,advancing our understanding of complex environmental exposures and their health impacts on environmental epidemiology and toxicology.
基金the expense of a grant of the Russian Science Foundation(project No.23-69-10006),https://rscf.ru/project/23-69-10006/(accessed on 6 May 2025).
文摘The article considers a relaxation of the water/polypropylene glycol-425 solution with a lower critical solution temperature(LCST)following its pulsed superheating concerning liquid-liquid and liquid-vapor equilibrium lines,as well as the liquid-liquid spinodal.Superheating was performed using the pulsed heat generation method in a micro-sized wire probe.The main heating mode was the constant(over the pulse length)power mode.Characteristic heating rates ranged from 0.05×10^(5) to 2×10^(5) K/s,while the degree of superheating concerning the spinodal was up to 200 K.The temperature of spontaneous boiling-up and the amplitude of the corresponding signal were monitored as functions of the heating rate set by the power value.The results demonstrate an example of the interaction of liquidliquid and liquid-vapor phase transitions,as well as the spinodal decomposition of a solution with LCST against the background of its unstable states.We proposed a physical model to explain the minimum spontaneous boiling-up temperature revealed within a certain range of heating rates,which is not typical of completely miscible solutions.Further research will focus on establishing a general criterion for the possibility of spinodal decomposition of such solutions under the conditions of rapid heating.
基金supported in part by the key project supported by the Joint Funds of the National Natural Science Foundation of China(grant No.U2433210)Shaanxi Province Postdoctoral Science Foundation(2024BSHSDZZ225)+1 种基金Natural Science Basic Research Program of Shaanxi Province(2025JC-YBQN-595)the Fundamental Research Funds for the Central Universities,CHD(300102215102).
文摘The use of hot recycled asphalt mixture(HRAM)allows for a reduction in the depletion of non-renewable resources and presents environmental benefits.However,concerns arise regarding the performance of HRAM due to the lower degree of blending(DOB)of virgin and aged asphalt(V&A asphalt).This paper aims to provide an up-to-date review on the DOB of V&A asphalt in HRAM.Initially,the paper introduces the DOB of V&A asphalt,followed by an analysis of the blending theory,evaluation methods,and influencing factors of DOB.Subsequently,the effect of DOB on the performance of HRAM is investigated,and molecular dynamic simulation is utilized to analyze the blend of V&A asphalt.Finally,methods for improving DOB are summarized.It was found that the use of high-resolution microscopy with tracer methods such as SEM/EDS was an effective way to characterize DOB.Furthermore,the chemical composition and colloid structure between virgin and aged asphalt are crucial to DOB.Additionally,improving DOB by utilizing the coupling effect of time and temperature during transportation,paving,and compaction stages is promising.Future research should focus on standardizing test methods,refining field simulation models,and developing intelligent construction technologies to achieve more efficient and durable blending.This review provides theoretical guidance and practical references for improving the DOB of V&A asphalt and promoting sustainable pavement construction.
基金supported by the Korea Agency for Infrastructure Technology Advancement under the Ministry of Land,Infrastructure and Transport (Grant No.RS-2024-00410248)by National Research Foundation of Korea (NRF)grants funded by the Korean government (MSIT) (Grant No.RS-2022R1C1C1007296).
文摘Suffusion is the process defined as the migration of relatively small soil particles through the pores of a soil matrix composed of relatively large particles,driven by substantial hydrodynamic forces and weak attraction energies.This study investigates the influence of flow direction(upward and downward)on suffusion induced by interaction energies in sand-clay mixtures under both saturated and unsaturated conditions.The impact of clay mineralogy(kaolinite,illite,and montmorillonite),sand-grain size,and ionic concentration(IC)gradient were discussed based on the observed breakthrough curves(BTCs)and relative saturation rate(Sr)during injection(particularly for unsaturated conditions).Under saturated conditions,higher susceptibility to suffusion was observed in sand-kaolinite and sand-illite mixtures under downward flow compared to upward flow,whereas the suffusion of montmorillonite was more significant under upward flow than under downward flow.In contrast,for unsaturated conditions,more substantial suffusion of kaolinite and illite particles occurred under upward flow compared to downward flow,whereas the opposite trend was observed in sand-montmorillonite mixtures.In addition,the impact of sand-grain size(or the size ratio between sand and clay)on the suffusion of kaolinite and illite under unsaturated conditions suggests a reduced size ratio that leads to relatively significant suffusion under downward flow compared to upward flow.The findings presented in this study contribute to a comprehensive understanding of the influence of flow direction on suffusion in sand-clay mixtures under both saturated and unsaturated conditions.
基金supported by the Key Project of the NationalLanguage Commission(No.ZDI145-110)the AcademicResearch Projects of Beijing Union University(No.ZK20202514)+1 种基金the Key Laboratory Project(No.YYZN-2024-6)the Project for the Construction and Support of High-Level Innovative Teams in Beijing Municipal Institutions(No.BPHR20220121).
文摘Gaze estimation,a crucial non-verbal communication cue,has achieved remarkable progress through convolutional neural networks.However,accurate gaze prediction in uncon-strained environments,particularly in extreme head poses,partial occlusions,and abnormal lighting,remains challenging.Existing models often struggle to effectively focus on discriminative ocular features,leading to suboptimal performance.To address these limitations,this paper proposes dual-branch gaze estimation with Gaussian mixture distribution heatmaps and dynamic adaptive loss function(DMGDL),a novel dual-branch gaze estimation algorithm.By introducing Gaussian mixture distribution heatmaps centered on pupil positions as spatial attention guides,the model is enabled to prioritize ocular regions.Additionally,a dual-branch network architecture is designed to separately extract features for yaw and pitch angles,enhancing flexibility and mitigating cross-angle interference.A dynamic adaptive loss function is further formulated to address discontinuities in angle estimation,improving robustness and convergence stability.Experimental evaluations on three benchmark datasets demonstrate that DMGDL outperforms state-of-the-art methods,achiev-ing a mean angular error of 3.98°on the Max-Planck institute for informatics face gaze(MPI-IFaceGaze)dataset,10.21°on the physically unconstrained gaze estimation in the wild(Gaze360)dataset and 6.14°on the real-time eye gaze estimation in natural environments(RT-Gene)dataset,exhibiting superior generalization and robustness.
基金Supported by Science and Technology Fund for Basic Research of Guizhou Province([2020]1Y010)National Nature Sciences Foundation of China(11901260,12071096,12501342)Specialized Fund for the Doctoral Development of Kaili University(BS202502028)。
文摘The upper bound on the model error will be decreased when the mean square error and the maximum distance deviation are sufficiently small in the uniform designs for mixture experiments and the design is more robust for the model.However,the analytical expressions of MSED and MD are currently only available in the hypercube,but both types of deviations in other studies are just approximations.Although it can obtain good approximations in the low-dimensional case,the calculation will be more complicated for an experiment with more variables.Therefore,in this paper,an algorithm based on lattice point partitioning design is proposed to obtain the analytical expression of the MSED and MD in the region covered by the lattice points.Furthermore,the design’s optimality is considered and illustrated by examples under the same uniformity.
基金This study conducted by Moscow Power Engineering Institute was financially supported by the Ministry of Science and Higher Education of the Russian Federation(project No.FSWF-2023-0014,contract No.075-03-2023-383,2023/18/01).
文摘The Russian energy sector remains heavily reliant on thermal power plants,with gas generation accounting for approximately 66%of the installed capacity.However,the industry faces challenges such as depletion of reserves,rising prices for hydrocarbons,and increasing concentrations of carbon dioxide in the atmosphere.This study focuses on developing new scientific and technical solutions to increase the efficiency and environmental safety of combined cycle power units.The research involves structural and parametric optimization of trinary cycle power plants operating on a methane-hydrogen mixture,as well as the development and optimization of turbine and heat exchange equipment for low-temperature power plants.The results show that the transition to trinary CCGT(Combine Cycle Gas Turbine)units with deep utilization and the use of hydrogen fuel can significantly reduce specific CO_(2) emissions and increase energy efficiency up to 0.21%with also increases in capacity of turbine of approximately 17 MW.The aim of this research is to calculate the efficiency,cost effectiveness and environmental-friendly solution for power generation using mixture of hydrogen-methane as fuel in combine cycle power plant that includes ORC.Additionally,the efficiency of the organic Rankine Cycle(ORC)benefits from the increased moisture,with capacity improvements of 1–2 MW observed when the hydrogen proportion rises from 25%to 50%.Moreover,the potential for zero emissions,coupled with significant increases in power output and efficiency,underscores hydrogen’s role as a pivotal component in the future of energy production.
基金jointly supported by the Fundamental Research Funds for the Central Universities(Grant No.xzy012023075)the Zhejiang Engineering Research Center of Intelligent Urban Infrastructure(Grant No.IUI2023-YB-12).
文摘The computational accuracy and efficiency of modeling the stress spectrum derived from bridge monitoring data significantly influence the fatigue life assessment of steel bridges.Therefore,determining the optimal stress spectrum model is crucial for further fatigue reliability analysis.This study investigates the performance of the REBMIX algorithm in modeling both univariate(stress range)and multivariate(stress range and mean stress)distributions of the rain-flowmatrix for a steel arch bridge,usingAkaike’s Information Criterion(AIC)as a performance metric.Four types of finitemixture distributions—Normal,Lognormal,Weibull,and Gamma—are employed tomodel the stress range.Additionally,mixed distributions,including Normal-Normal,Lognormal-Normal,Weibull-Normal,and Gamma-Normal,are utilized to model the joint distribution of stress range and mean stress.The REBMIX algorithm estimates the number of components,component weights,and component parameters for each candidate finite mixture distribution.The results demonstrate that the REBMIX algorithm-based mixture parameter estimation approach effectively identifies the optimal distribution based on AIC values.Furthermore,the algorithm exhibits superior computational efficiency compared to traditional methods,making it highly suitable for practical applications.
