Fatigue properties are crucial for critical aero-engine components in extreme serviceenvironments,which are significantly affected by surface integrity(SI)indexes(especially surface topography,residual stressσ_(res),...Fatigue properties are crucial for critical aero-engine components in extreme serviceenvironments,which are significantly affected by surface integrity(SI)indexes(especially surface topography,residual stressσ_(res),and microhardness)after machining processes.Normal-direction ultrasonic vibration-assisted face grinding(ND-UVAFG)has advantages in improving the machinability of Inconel 718,but there is a competitive relationship between higher compressiveσ_(res)and higher surface roughness R_(a)in affecting fatigue strength.The lack of a quantitative relationship between multiple SI indexes and fatigue strength makes theindeterminacy of a regulatory strategy for improving fatigue properties.In this work,a model of fatigue strength(σ_f)_(sur)considering multiple SI indexes was developed.Then,high-cycle fatigue tests were carried out on Inconel 718 samples with different SI characteristics,and the influence of ND-UVAFG process parameters on SI was analyzed.Based on SI indexes data,the(σ_f)_(sur)distribution in the grinding surface layer for ND-UVAFG Inconel 718 samples was determined using the developed model,and then the fatigue crack initiation(FCI)sites were furtherpredicted.The predicted FCI sites corresponded well with the experimental results,therebyverifying this model.A strategy for improving the fatigue life was proposed in this work,which was to transfer the fatigue source from the machined surface to the bulk material by controlling the SI indexes.Finally,a critical condition of SI indexes that FCI sites appeared on the surface or in bulk material was given by fitting the predicted results.According to the critical condition,an SI field where FCI sites appeared in the bulk material could be obtained.In this field,thefatigue life of Inconel 718 samples could be improved by approximately 140%.展开更多
The seasonal changes in dissolved organic matter(DOM),and its correlation with the release of internal nutrients during the annual cycle of cyanobacteria in the eutrophic Lake Chaohu,China,were investigated from four ...The seasonal changes in dissolved organic matter(DOM),and its correlation with the release of internal nutrients during the annual cycle of cyanobacteria in the eutrophic Lake Chaohu,China,were investigated from four sampling periods between November 2020 and July 2021.The DOM fluorescence components were identified as protein-like C1,microbial humic-like C2,and terrestrial humic-like C3.The highest total fluorescence intensity(FT)of DOM in sediments during the incubation stage is due to the decomposition and degradation of cyanobacteria remains.The lowest humification of DOM and the highest proportion of C1 in waters during the initial cyanobacterial growth indicate that fresh algae are the main source.The highest molecular weight of DOM and FT of the C2 in sediments during cyanobacterial outbreaks indicate the concurrent deposition of undegraded cyanobacterial remains and microbial degradation.The components of DOM are affected mainly by the dissolved total phosphorus in waters,while the temperature drives the annual cycle of cyanobacteria.The decreasing C1 in sediments and increasing nutrients in waters from the cyanobacterial incubation to outbreak indicate that mineralization of algal organic matter contributes importantly to the release of internal nutrients,with the strongest release of phosphorus observed during the early growth of cyanobacteria.The humic-like C2 and C3 components could also affect the dynamics of internal phosphorus through the formation of organic colloids and organic–inorganic ligands.The results show that the degradation of DOM leads to nutrients release and thus supports the continuous growth of cyanobacteria in eutrophic Lake Chaohu.展开更多
Water pollution is a global environmental issue with multi-dimensional infl uences on human life.Some strategies,such as photo-Fenton reaction,have been employed to remove recalcitrant pollutants.Two-dimensional(2D)gr...Water pollution is a global environmental issue with multi-dimensional infl uences on human life.Some strategies,such as photo-Fenton reaction,have been employed to remove recalcitrant pollutants.Two-dimensional(2D)graphene and its threedimensional(3D)confi gurations have attracted considerable attention as emerging carbon-based catalysts in photo-Fenton fi elds owing to their alluring properties in electron transfer,reactant adsorption,and light response.This review summarizes the recent developments in 2D and 3D graphene-based catalysts for photo-Fenton reactions.Their structures,characteristics,activity,and mechanisms are discussed.The conclusions and outlooks are proposed for the profound understanding of challenges and future directions.展开更多
Three-dimensional graphene-based aerogels have promising applications in oil adsorption and environmental restoration.However,current research of graphene-based aerogels is often hindered by high preparation cost,poor...Three-dimensional graphene-based aerogels have promising applications in oil adsorption and environmental restoration.However,current research of graphene-based aerogels is often hindered by high preparation cost,poor mechanical properties and low recycling efficiency.Here,superelastic graphene aerogel(SGA)was prepared through one-step freezing and twice hydrothermal reduction followed by drying under ambient pressure.The simple atmospheric drying provides a possibility for large-scale preparation of high performance graphene-based aerogels.The prepared SGA not only has the ability of highly repeatable compression rebound,but also exhibits excellent oil adsorption performance.And the overall performance of SGA is better than most of graphenebased aerogels prepared by freeze drying.After the SGA was cyclically compressed with 70%strain for 300 times,it can return to the original shape and height substantially.SGA retained about 90%of the initial adsorption capacity after 50 cycles of adsorption and compression regeneration for cyclohexane.展开更多
This paper introduces the experimental designs and outputs of the Diagnostic,Evaluation and Characterization of Klima(DECK),historical,Scenario Model Intercomparison Project(MIP),and Paleoclimate MIP(PMIP)experiments ...This paper introduces the experimental designs and outputs of the Diagnostic,Evaluation and Characterization of Klima(DECK),historical,Scenario Model Intercomparison Project(MIP),and Paleoclimate MIP(PMIP)experiments from the Nanjing University of Information Science and Technology Earth System Model version 3(NESM3).Results show that NESM3 reasonably simulates the modern climate and the major internal modes of climate variability.In the Scenario MIP experiment,changes in the projected surface air temperature(SAT)show robust“Northern Hemisphere(NH)warmer than Southern Hemisphere(SH)”and“land warmer than ocean”patterns,as well as an El Niño-like warming over the tropical Pacific.Changes in the projected precipitation exhibit“NH wetter than SH”and“eastern hemisphere gets wetter and western hemisphere gets drier”patterns over the tropics.These precipitation patterns are driven by circulation changes owing to the inhomogeneous warming patterns.Two PMIP experiments show enlarged seasonal cycles of SAT and precipitation over the NH due to the seasonal redistribution of solar radiation.Changes in the climatological mean SAT,precipitation,and ENSO amplitudes are consistent with the results from PMIP4 models.The NESM3 outputs are available on the Earth System Grid Federation nodes for data users.展开更多
With the rapid development of the petroleum industry and oil spill occurredfrequently in recent years, marine oil pollution is serious. Oil pollution from terrestrialsources is an important source of marine oil pollut...With the rapid development of the petroleum industry and oil spill occurredfrequently in recent years, marine oil pollution is serious. Oil pollution from terrestrialsources is an important source of marine oil pollution. In China, oil pollution fromterrestrial sources accounted for more than 80% of the total marine pollutants. Wetlandhas great ecological and environmental value, and researches found that wetland hasthe function of purifying oil pollutants. Beitang Estuary in Tianjin Binhai New Area is amajor fishery port, and also the main sewage outfall. In recent years, with the increaseof oil pollution from terrestrial sources, water quality in Beitang River is deteriorating.The Beitang Estuary has a large area of natural Spartina alterniflora wetland, whichmay effectively remove oil pollution. Environmental investigation was carried out on thewharf, channel and coastal zone near Beitang Estuary. The results showed that theeutrophication in Beitang Estuary is serious, and the water quality is inferior to theworse than the fourth class of sea water quality. Inorganic nitrogen, active phosphateand petroleum hydrocarbons are the main pollutants. Reed, Spartina alterniflora andSeepweed were the dominant species in the Beitang Estuary, and petroleumhydrocarbons were detected in the three plants. It showed that the Beitang Estuary waspolluted by petroleum hydrocarbons, and the three kinds of plants have the ability toabsorb petroleum hydrocarbons. Survey results showed that, whether in the surfaceseawater or sediment, the oil content near the wharf was higher than the channel; thepetroleum hydrocarbon content in the channel was higher than the coastal zone. Theroots, stems and leaves of Spartina alterniflora can intercept oil pollution from terrestrialsources. In addition to absorbing petroleum hydrocarbons, Spartina alterniflora alsoprovides a good habitat for microorganisms,to accelerate microbial degradation ofpetroleum hydrocarbon. Spartina alterniflora wetland has the obvious effect forreducing terrigenous oil pollutants.展开更多
Different fusion algorithm has its own advantages and limitations,so it is very difficult to simply evaluate the good points and bad points of the fusion algorithm. Whether an algorithm was selected to fuse object ima...Different fusion algorithm has its own advantages and limitations,so it is very difficult to simply evaluate the good points and bad points of the fusion algorithm. Whether an algorithm was selected to fuse object images was also depended upon the sensor types and special research purposes. Firstly,five fusion methods,i. e. IHS,Brovey,PCA,SFIM and Gram-Schmidt,were briefly described in the paper. And then visual judgment and quantitative statistical parameters were used to assess the five algorithms. Finally,in order to determine which one is the best suitable fusion method for land cover classification of IKONOS image,the maximum likelihood classification( MLC) was applied using the above five fusion images. The results showed that the fusion effect of SFIM transform and Gram-Schmidt transform were better than the other three image fusion methods in spatial details improvement and spectral information fidelity,and Gram-Schmidt technique was superior to SFIM transform in the aspect of expressing image details. The classification accuracy of the fused image using Gram-Schmidt and SFIM algorithms was higher than that of the other three image fusion methods,and the overall accuracy was greater than 98%. The IHS-fused image classification accuracy was the lowest,the overall accuracy and kappa coefficient were 83. 14% and 0. 76,respectively. Thus the IKONOS fusion images obtained by the Gram-Schmidt and SFIM were better for improving the land cover classification accuracy.展开更多
Laser ablation is an important process during Laser-Assisted Grinding(LAG)of hard and brittle materials.To realize controllable material removal during laser ablation of RB-SiC composites,ablation experiments under di...Laser ablation is an important process during Laser-Assisted Grinding(LAG)of hard and brittle materials.To realize controllable material removal during laser ablation of RB-SiC composites,ablation experiments under different Laser Energy Density(LAED)and LAG experiments are conducted.Evolution rules and mechanism of physical phase,ablation morphology and crack characteristics caused by laser irradiation are investigated.The forces of LAG and Conventional Grinding(CG)are compared.The results show that ablation surface changes from slight oxidation to obvious material removal with LAED increasing,and ablation depth increases gradually.The ablation products change from submicron SiO_(2)particles to nanoscale particles and floccule.High LAED promotes SiC decomposition and sublimation,which leads to the increase of C element.The SiC phase forms corrugated shape in recast layer and columnar shape in Heat Affected Zone(HAZ)at 56 J/mm^(2).The cold and heat cycle leads to formation of fishbone crack.For ablation specimen under 30 J/mm^(2),the grinding force can be reduced by a maximum of 39%and brittle damage region is reduced.The material removal and microcrack generated will significantly reduce the hardness and improve machinability,which can promote grinding efficiency.展开更多
Heterogeneous Fenton has been widely used in the disposal of organic pollutants,however,slow regeneration of≡Fe(II)remains limitation for its practical application of long-term treatment.Herein,we come up with a nove...Heterogeneous Fenton has been widely used in the disposal of organic pollutants,however,slow regeneration of≡Fe(II)remains limitation for its practical application of long-term treatment.Herein,we come up with a novel Fe-based heterogeneous Fenton catalyst named as FeS_(x)O_(y)-X(X is the ratio of ethylene glycol to N,N-dimethylformamide).With the help of the abundant defect electrons in Sulfur vacancies,≡Fe(Ⅱ)regeneration on the surface of FeS_(x)O_(y)-1:1 was accelerated,resulting in a stable proportion of≡Fe(Ⅱ)on the surface,which maintained continuously stable generation of hydroxyl radical(·OH)and singlet oxygen(^(1)O_(2)).Thus,without any organic reagents or cocatalysts,FeS_(x)O_(y)-1:1 based Fenton system achieved effective long-term degradation of 560 mg/L quinoline within only 7 days,which was evidently better than reported Fe S and SV-Fe S_(2)(SV:Sulfur vacancy).The system had excellent adaptability to water quality and the COD removal rate of biochemical wastewater was as high as 79.8%.展开更多
基金support from the National Science Fund of China(52325506)the National Science and Technology Major Project(2017-VII-0002-0095)Fundamental Research Funds for the Central Universities(DUT22LAB501)。
文摘Fatigue properties are crucial for critical aero-engine components in extreme serviceenvironments,which are significantly affected by surface integrity(SI)indexes(especially surface topography,residual stressσ_(res),and microhardness)after machining processes.Normal-direction ultrasonic vibration-assisted face grinding(ND-UVAFG)has advantages in improving the machinability of Inconel 718,but there is a competitive relationship between higher compressiveσ_(res)and higher surface roughness R_(a)in affecting fatigue strength.The lack of a quantitative relationship between multiple SI indexes and fatigue strength makes theindeterminacy of a regulatory strategy for improving fatigue properties.In this work,a model of fatigue strength(σ_f)_(sur)considering multiple SI indexes was developed.Then,high-cycle fatigue tests were carried out on Inconel 718 samples with different SI characteristics,and the influence of ND-UVAFG process parameters on SI was analyzed.Based on SI indexes data,the(σ_f)_(sur)distribution in the grinding surface layer for ND-UVAFG Inconel 718 samples was determined using the developed model,and then the fatigue crack initiation(FCI)sites were furtherpredicted.The predicted FCI sites corresponded well with the experimental results,therebyverifying this model.A strategy for improving the fatigue life was proposed in this work,which was to transfer the fatigue source from the machined surface to the bulk material by controlling the SI indexes.Finally,a critical condition of SI indexes that FCI sites appeared on the surface or in bulk material was given by fitting the predicted results.According to the critical condition,an SI field where FCI sites appeared in the bulk material could be obtained.In this field,thefatigue life of Inconel 718 samples could be improved by approximately 140%.
基金supported by the University Natural Science Research Project of Anhui Province (No. KJ2019A0042)the Key Research and Development Program of Anhui Province (No. 201904a07020071)
文摘The seasonal changes in dissolved organic matter(DOM),and its correlation with the release of internal nutrients during the annual cycle of cyanobacteria in the eutrophic Lake Chaohu,China,were investigated from four sampling periods between November 2020 and July 2021.The DOM fluorescence components were identified as protein-like C1,microbial humic-like C2,and terrestrial humic-like C3.The highest total fluorescence intensity(FT)of DOM in sediments during the incubation stage is due to the decomposition and degradation of cyanobacteria remains.The lowest humification of DOM and the highest proportion of C1 in waters during the initial cyanobacterial growth indicate that fresh algae are the main source.The highest molecular weight of DOM and FT of the C2 in sediments during cyanobacterial outbreaks indicate the concurrent deposition of undegraded cyanobacterial remains and microbial degradation.The components of DOM are affected mainly by the dissolved total phosphorus in waters,while the temperature drives the annual cycle of cyanobacteria.The decreasing C1 in sediments and increasing nutrients in waters from the cyanobacterial incubation to outbreak indicate that mineralization of algal organic matter contributes importantly to the release of internal nutrients,with the strongest release of phosphorus observed during the early growth of cyanobacteria.The humic-like C2 and C3 components could also affect the dynamics of internal phosphorus through the formation of organic colloids and organic–inorganic ligands.The results show that the degradation of DOM leads to nutrients release and thus supports the continuous growth of cyanobacteria in eutrophic Lake Chaohu.
文摘Water pollution is a global environmental issue with multi-dimensional infl uences on human life.Some strategies,such as photo-Fenton reaction,have been employed to remove recalcitrant pollutants.Two-dimensional(2D)graphene and its threedimensional(3D)confi gurations have attracted considerable attention as emerging carbon-based catalysts in photo-Fenton fi elds owing to their alluring properties in electron transfer,reactant adsorption,and light response.This review summarizes the recent developments in 2D and 3D graphene-based catalysts for photo-Fenton reactions.Their structures,characteristics,activity,and mechanisms are discussed.The conclusions and outlooks are proposed for the profound understanding of challenges and future directions.
基金the financial support of National Natural Science Foundation of China (22078366)
文摘Three-dimensional graphene-based aerogels have promising applications in oil adsorption and environmental restoration.However,current research of graphene-based aerogels is often hindered by high preparation cost,poor mechanical properties and low recycling efficiency.Here,superelastic graphene aerogel(SGA)was prepared through one-step freezing and twice hydrothermal reduction followed by drying under ambient pressure.The simple atmospheric drying provides a possibility for large-scale preparation of high performance graphene-based aerogels.The prepared SGA not only has the ability of highly repeatable compression rebound,but also exhibits excellent oil adsorption performance.And the overall performance of SGA is better than most of graphenebased aerogels prepared by freeze drying.After the SGA was cyclically compressed with 70%strain for 300 times,it can return to the original shape and height substantially.SGA retained about 90%of the initial adsorption capacity after 50 cycles of adsorption and compression regeneration for cyclohexane.
基金supported by the Natural Science Foundation of China of Jiangsu Province(Grant No.BK20180812,BK20181412)the National Natural Science Foundation of China(Grant No.42005017,41675072,41922033)the Startup Foundation for Introducing Talent of NUIST(Grant No.2018r063)。
文摘This paper introduces the experimental designs and outputs of the Diagnostic,Evaluation and Characterization of Klima(DECK),historical,Scenario Model Intercomparison Project(MIP),and Paleoclimate MIP(PMIP)experiments from the Nanjing University of Information Science and Technology Earth System Model version 3(NESM3).Results show that NESM3 reasonably simulates the modern climate and the major internal modes of climate variability.In the Scenario MIP experiment,changes in the projected surface air temperature(SAT)show robust“Northern Hemisphere(NH)warmer than Southern Hemisphere(SH)”and“land warmer than ocean”patterns,as well as an El Niño-like warming over the tropical Pacific.Changes in the projected precipitation exhibit“NH wetter than SH”and“eastern hemisphere gets wetter and western hemisphere gets drier”patterns over the tropics.These precipitation patterns are driven by circulation changes owing to the inhomogeneous warming patterns.Two PMIP experiments show enlarged seasonal cycles of SAT and precipitation over the NH due to the seasonal redistribution of solar radiation.Changes in the climatological mean SAT,precipitation,and ENSO amplitudes are consistent with the results from PMIP4 models.The NESM3 outputs are available on the Earth System Grid Federation nodes for data users.
基金supported by the Project of Tianjin with Spill Oil Accident from Penglai Oil field 19-3 Compensation (No. 19-3BC2014-05)Tianjin Municipal Science and Technology Planning Project (15ZCZDSF00620, 15JCYBJC23200)
文摘With the rapid development of the petroleum industry and oil spill occurredfrequently in recent years, marine oil pollution is serious. Oil pollution from terrestrialsources is an important source of marine oil pollution. In China, oil pollution fromterrestrial sources accounted for more than 80% of the total marine pollutants. Wetlandhas great ecological and environmental value, and researches found that wetland hasthe function of purifying oil pollutants. Beitang Estuary in Tianjin Binhai New Area is amajor fishery port, and also the main sewage outfall. In recent years, with the increaseof oil pollution from terrestrial sources, water quality in Beitang River is deteriorating.The Beitang Estuary has a large area of natural Spartina alterniflora wetland, whichmay effectively remove oil pollution. Environmental investigation was carried out on thewharf, channel and coastal zone near Beitang Estuary. The results showed that theeutrophication in Beitang Estuary is serious, and the water quality is inferior to theworse than the fourth class of sea water quality. Inorganic nitrogen, active phosphateand petroleum hydrocarbons are the main pollutants. Reed, Spartina alterniflora andSeepweed were the dominant species in the Beitang Estuary, and petroleumhydrocarbons were detected in the three plants. It showed that the Beitang Estuary waspolluted by petroleum hydrocarbons, and the three kinds of plants have the ability toabsorb petroleum hydrocarbons. Survey results showed that, whether in the surfaceseawater or sediment, the oil content near the wharf was higher than the channel; thepetroleum hydrocarbon content in the channel was higher than the coastal zone. Theroots, stems and leaves of Spartina alterniflora can intercept oil pollution from terrestrialsources. In addition to absorbing petroleum hydrocarbons, Spartina alterniflora alsoprovides a good habitat for microorganisms,to accelerate microbial degradation ofpetroleum hydrocarbon. Spartina alterniflora wetland has the obvious effect forreducing terrigenous oil pollutants.
基金Supported by Chinese National Natural Science Foundation(51208016)Beijing Natural Science Foundation(8122008)Beijing Education Commission Fund(KM201310005023)
文摘Different fusion algorithm has its own advantages and limitations,so it is very difficult to simply evaluate the good points and bad points of the fusion algorithm. Whether an algorithm was selected to fuse object images was also depended upon the sensor types and special research purposes. Firstly,five fusion methods,i. e. IHS,Brovey,PCA,SFIM and Gram-Schmidt,were briefly described in the paper. And then visual judgment and quantitative statistical parameters were used to assess the five algorithms. Finally,in order to determine which one is the best suitable fusion method for land cover classification of IKONOS image,the maximum likelihood classification( MLC) was applied using the above five fusion images. The results showed that the fusion effect of SFIM transform and Gram-Schmidt transform were better than the other three image fusion methods in spatial details improvement and spectral information fidelity,and Gram-Schmidt technique was superior to SFIM transform in the aspect of expressing image details. The classification accuracy of the fused image using Gram-Schmidt and SFIM algorithms was higher than that of the other three image fusion methods,and the overall accuracy was greater than 98%. The IHS-fused image classification accuracy was the lowest,the overall accuracy and kappa coefficient were 83. 14% and 0. 76,respectively. Thus the IKONOS fusion images obtained by the Gram-Schmidt and SFIM were better for improving the land cover classification accuracy.
基金funded by the Fundamental Research Funds for the Central Universities,China(Nos.DUT21GF403,DUT22YG210,DUT22LAB117)the High Level Talents Innovation Plan of Dalian,China(No.2020RD02)financial support from the Shenzhen Science and Technology Innovation Commission Project,China(No.JSGG20210420091802007)。
文摘Laser ablation is an important process during Laser-Assisted Grinding(LAG)of hard and brittle materials.To realize controllable material removal during laser ablation of RB-SiC composites,ablation experiments under different Laser Energy Density(LAED)and LAG experiments are conducted.Evolution rules and mechanism of physical phase,ablation morphology and crack characteristics caused by laser irradiation are investigated.The forces of LAG and Conventional Grinding(CG)are compared.The results show that ablation surface changes from slight oxidation to obvious material removal with LAED increasing,and ablation depth increases gradually.The ablation products change from submicron SiO_(2)particles to nanoscale particles and floccule.High LAED promotes SiC decomposition and sublimation,which leads to the increase of C element.The SiC phase forms corrugated shape in recast layer and columnar shape in Heat Affected Zone(HAZ)at 56 J/mm^(2).The cold and heat cycle leads to formation of fishbone crack.For ablation specimen under 30 J/mm^(2),the grinding force can be reduced by a maximum of 39%and brittle damage region is reduced.The material removal and microcrack generated will significantly reduce the hardness and improve machinability,which can promote grinding efficiency.
基金supported by the National Natural Science Foundation of China (22176060 and 21822603)Shanghai Municipal Science and Technology Major Project (2018SHZDZX03)+1 种基金the Program of Introducing Talents of Discipline to Universities (B16017)the Science and Technology Commission of Shanghai Municipality (20DZ2250400)。
基金supported by the National Natural Science Foundation of China(No.22176060)Project supported by Shanghai Municipal Science and Technology Major Project(No.2018SHZDZX03)+1 种基金the Program of Introducing Talents of Discipline to Universities(No.B16017)the Science and Technology Commission of Shanghai Municipality(No.20DZ2250400)。
文摘Heterogeneous Fenton has been widely used in the disposal of organic pollutants,however,slow regeneration of≡Fe(II)remains limitation for its practical application of long-term treatment.Herein,we come up with a novel Fe-based heterogeneous Fenton catalyst named as FeS_(x)O_(y)-X(X is the ratio of ethylene glycol to N,N-dimethylformamide).With the help of the abundant defect electrons in Sulfur vacancies,≡Fe(Ⅱ)regeneration on the surface of FeS_(x)O_(y)-1:1 was accelerated,resulting in a stable proportion of≡Fe(Ⅱ)on the surface,which maintained continuously stable generation of hydroxyl radical(·OH)and singlet oxygen(^(1)O_(2)).Thus,without any organic reagents or cocatalysts,FeS_(x)O_(y)-1:1 based Fenton system achieved effective long-term degradation of 560 mg/L quinoline within only 7 days,which was evidently better than reported Fe S and SV-Fe S_(2)(SV:Sulfur vacancy).The system had excellent adaptability to water quality and the COD removal rate of biochemical wastewater was as high as 79.8%.
