Bending deformation behaviors of solution treated(ST),natural aged(NA)and T6tempered6063aluminum alloy sheetswere studied by three-point bending tests.The changes of bending force,interior angle,bending radius and she...Bending deformation behaviors of solution treated(ST),natural aged(NA)and T6tempered6063aluminum alloy sheetswere studied by three-point bending tests.The changes of bending force,interior angle,bending radius and sheet thickness in thefillet region were analyzed by experimental measurements and numerical simulations.The results showed that the bendingcharacteristics were strongly dependent on the heat treatment conditions.The T6alloy sheets were bent more sharply and localplastic deformation occurred severely in the fillet region.However,the ST and NA alloy sheets exhibited relatively uniform bendingdeformation and large bending radius.The bending force of T6alloy was the highest,followed by the NA alloy and that of the STalloy was minimum.After unloading,as compared with the ST and NA alloys,the springback of T6alloys was markedly larger.Theaging time showed a positive sensitivity on the springback and non-uniform bending deformability.The bending characteristics areattributed to the combined effects of yield strength,yield ratio and coefficient of neutral layer.展开更多
The physicochemical properties of plasma-activated water(PAW)generated under different process conditions were investigated,and their changes under different storage conditions were also studied.The results showed tha...The physicochemical properties of plasma-activated water(PAW)generated under different process conditions were investigated,and their changes under different storage conditions were also studied.The results showed that increasing the processing time and power,and decreasing generated water volume,could cause an increase in the redox potential,conductivity,and temperature of PAW,and a decrease in its pH.A slower dissipation of the reactive oxygen and nitrogen species in PAW was found on storage at 4℃in a sealed conical flask than on storage at room temperature.The inactivation ability of plasma-activated lactic acid(LA)to Listeria monocytogenes(L.monocytogenes)and Pseudomonas aeruginosa(P.aeruginosa)was higher than that of PAW or LA alone under the same experimental conditions.The results of this study may provide theoretical information for the application of PAW as a potential antimicrobial agent in the future.展开更多
In the present paper, the author gives some comments on acupuncture treatment of diseases from 1) selecting acupoints based on seasonal conditions; 2) performing reinforcing or reducing needling manipulations in accor...In the present paper, the author gives some comments on acupuncture treatment of diseases from 1) selecting acupoints based on seasonal conditions; 2) performing reinforcing or reducing needling manipulations in accordance with the waxing and wanning of the moon; 3) conducting acupuncture treatment in accordance with the time and the state of disease; and 4) performing acupuncture treatment based on the prosperity or decline of the meridian-qi, which are described in medical book The Yellow Emperor's Internal Classic展开更多
Sewage sludge is a major source of fecal pathogens in the environment,and its application to land can result in a significant release of these pathogens into the soil.While conditioning treatments are crucial for impr...Sewage sludge is a major source of fecal pathogens in the environment,and its application to land can result in a significant release of these pathogens into the soil.While conditioning treatments are crucial for improving the dewatering process of sludge,their impact on the presence and behavior of fecal pathogens in soil remains unclear.This study aims to assess four extraction methods for recovering fecal pollution indicators from soil amended with unconditioned and conditioned sludge.The indicators include Escherichia coli(EC),human-specific HF183 Bacteroides(HF183),human adenovirus(HAdV),human BK polyomavirus(BKPyV),human JC polyomavirus(JCPyV),and cross-assembly phage(crAssphage).This study also examines how soil moisture content affects the decay of these fecal pollution indicators in soil amended with raw sludge and investigates the influence of conditioning treatments with cationic polyacrylamide(PAM),Fenton’s reagents,Fe[III]/CaO on their persistence in soil.The results indicated that the direct extraction method was the most effective and unbiased for recovering fecal pollution indicators from sludge-amended soil compared with the three elution-concentration methods.All fecal pollution indicators,except HAdV,remained stable under dry soil conditions,while high soil moisture content(48.39%‒53.14%)slowed the decay rates of these indicators.During the application of sludge to soil,effective control of fecal pollution indicators was observed,with JCPyV and HAdV becoming undetectable within a short period.The log reduction values of HF183,BKPyV,and crAssphage ranged from 0.1 to 2.8 logs after 30 d of cultivation.The application of conditioned sludge,especially Fenton’s reagent-conditioned sludge,resulted in a reduction in human fecal contamination in the receiving soil.Therefore,implementing appropriate conditioning methods,such as using Fenton’s reagent,can effectively mitigate the health risks associated with fecal pathogens.展开更多
In the present study, a response surface methodology was used to optimize the electroleaching of Mn from low-grade pyrolusite. Ferrous sulfate heptahydrate was used in this reaction as a reducing agent in sulfuric aci...In the present study, a response surface methodology was used to optimize the electroleaching of Mn from low-grade pyrolusite. Ferrous sulfate heptahydrate was used in this reaction as a reducing agent in sulfuric acid solutions. The effect of six process variables, including the mass ratio of ferrous sulfate heptahydrate to pyrolusite, mass ratio of sulfuric acid to pyrolusite, liquid-to-solid ratio, current density, leaching temperature, and leaching time, as well as their binary interactions, were modeled. The results revealed that the order of these factors with respect to their effects on the leaching efficiency were mass ratio of ferrous sulfate heptahydrate to pyrolusite 〉 leaching time 〉 mass ratio of sulfuric acid to pyrolusite 〉 liquid-to-solid ratio 〉 leaching temperature 〉 current density. The optimum conditions were as follows： 1.10：1 mass ratio of ferrous sulfate heptahydrate to pyrolusite, 0.9：1 mass ratio of sulfuric acid to pyrolusite, liquid-to-solid ratio of 0.7：1, current density of 947 A/m^2, leaching time of 180 min, and leaching temperature of 73°C. Under these conditions, the predicted leaching efficiency for Mn was 94.1%; the obtained experimental result was 95.7%, which confirmed the validity of the model.展开更多
An orthogonal test was used to optimize the reaction conditions of roasting zinc oxide ore using（NH_4）_2SO_4. The optimized reaction conditions are defined as an（NH_4）_2SO_4/zinc molar ratio of 1.4：1, a roasting ...An orthogonal test was used to optimize the reaction conditions of roasting zinc oxide ore using（NH_4）_2SO_4. The optimized reaction conditions are defined as an（NH_4）_2SO_4/zinc molar ratio of 1.4：1, a roasting temperature of 440°C, and a thermostatic time of 60 min. The molar ratio of（NH_4）_2SO_4/zinc is the most predominant factor and the roasting temperature is the second significant factor that governs the zinc extraction. Thermogravimetric-differential thermal analysis was used for（NH_4）_2SO_4 and zinc mixed in a molar ratio of 1.4：1 at the heating rates of 5, 10, 15, and 20 K·min-1. Two strong endothermic peaks indicate that the complex chemical reactions occur at approximately 290°C and 400°C. XRD analysis was employed to examine the transformations of mineral phases during roasting process. Kinetic parameters, including reaction apparent activation energy, reaction order, and frequency factor, were calculated by the Doyle-Ozawa and Kissinger methods. Corresponding to the two endothermic peaks, the kinetic equations were obtained.展开更多
基金Projects(U1664252,51605234)supported by the National Natural Science Foundation of ChinaProject(2016YFB0101700)supported by the National Key Research and Development Program of ChinaProject(31665004)supported by the Open Fund of State Key Laboratory of Advanced Design and Manufacture for Vehicle Body
文摘Bending deformation behaviors of solution treated(ST),natural aged(NA)and T6tempered6063aluminum alloy sheetswere studied by three-point bending tests.The changes of bending force,interior angle,bending radius and sheet thickness in thefillet region were analyzed by experimental measurements and numerical simulations.The results showed that the bendingcharacteristics were strongly dependent on the heat treatment conditions.The T6alloy sheets were bent more sharply and localplastic deformation occurred severely in the fillet region.However,the ST and NA alloy sheets exhibited relatively uniform bendingdeformation and large bending radius.The bending force of T6alloy was the highest,followed by the NA alloy and that of the STalloy was minimum.After unloading,as compared with the ST and NA alloys,the springback of T6alloys was markedly larger.Theaging time showed a positive sensitivity on the springback and non-uniform bending deformability.The bending characteristics areattributed to the combined effects of yield strength,yield ratio and coefficient of neutral layer.
基金National Natural Science Foundation of China(No.32260643)for financial support of this study。
文摘The physicochemical properties of plasma-activated water(PAW)generated under different process conditions were investigated,and their changes under different storage conditions were also studied.The results showed that increasing the processing time and power,and decreasing generated water volume,could cause an increase in the redox potential,conductivity,and temperature of PAW,and a decrease in its pH.A slower dissipation of the reactive oxygen and nitrogen species in PAW was found on storage at 4℃in a sealed conical flask than on storage at room temperature.The inactivation ability of plasma-activated lactic acid(LA)to Listeria monocytogenes(L.monocytogenes)and Pseudomonas aeruginosa(P.aeruginosa)was higher than that of PAW or LA alone under the same experimental conditions.The results of this study may provide theoretical information for the application of PAW as a potential antimicrobial agent in the future.
文摘In the present paper, the author gives some comments on acupuncture treatment of diseases from 1) selecting acupoints based on seasonal conditions; 2) performing reinforcing or reducing needling manipulations in accordance with the waxing and wanning of the moon; 3) conducting acupuncture treatment in accordance with the time and the state of disease; and 4) performing acupuncture treatment based on the prosperity or decline of the meridian-qi, which are described in medical book The Yellow Emperor's Internal Classic
基金supported by the National Natural Science Foundation of China(Grant Nos.21976091 and 42207292)the Natural Science Foundation of Jiangsu Province(Grant Nos.BK20230040 and BK20220364).
文摘Sewage sludge is a major source of fecal pathogens in the environment,and its application to land can result in a significant release of these pathogens into the soil.While conditioning treatments are crucial for improving the dewatering process of sludge,their impact on the presence and behavior of fecal pathogens in soil remains unclear.This study aims to assess four extraction methods for recovering fecal pollution indicators from soil amended with unconditioned and conditioned sludge.The indicators include Escherichia coli(EC),human-specific HF183 Bacteroides(HF183),human adenovirus(HAdV),human BK polyomavirus(BKPyV),human JC polyomavirus(JCPyV),and cross-assembly phage(crAssphage).This study also examines how soil moisture content affects the decay of these fecal pollution indicators in soil amended with raw sludge and investigates the influence of conditioning treatments with cationic polyacrylamide(PAM),Fenton’s reagents,Fe[III]/CaO on their persistence in soil.The results indicated that the direct extraction method was the most effective and unbiased for recovering fecal pollution indicators from sludge-amended soil compared with the three elution-concentration methods.All fecal pollution indicators,except HAdV,remained stable under dry soil conditions,while high soil moisture content(48.39%‒53.14%)slowed the decay rates of these indicators.During the application of sludge to soil,effective control of fecal pollution indicators was observed,with JCPyV and HAdV becoming undetectable within a short period.The log reduction values of HF183,BKPyV,and crAssphage ranged from 0.1 to 2.8 logs after 30 d of cultivation.The application of conditioned sludge,especially Fenton’s reagent-conditioned sludge,resulted in a reduction in human fecal contamination in the receiving soil.Therefore,implementing appropriate conditioning methods,such as using Fenton’s reagent,can effectively mitigate the health risks associated with fecal pathogens.
基金financially supported by the "121" Scientific and Technological Supporting Demonstration Project of Chongqing, China (No. cstc2014zktjccx B0043)the Scientific Research and Technology Development Program of Guangxi, China (No. 2014BA10016)
文摘In the present study, a response surface methodology was used to optimize the electroleaching of Mn from low-grade pyrolusite. Ferrous sulfate heptahydrate was used in this reaction as a reducing agent in sulfuric acid solutions. The effect of six process variables, including the mass ratio of ferrous sulfate heptahydrate to pyrolusite, mass ratio of sulfuric acid to pyrolusite, liquid-to-solid ratio, current density, leaching temperature, and leaching time, as well as their binary interactions, were modeled. The results revealed that the order of these factors with respect to their effects on the leaching efficiency were mass ratio of ferrous sulfate heptahydrate to pyrolusite 〉 leaching time 〉 mass ratio of sulfuric acid to pyrolusite 〉 liquid-to-solid ratio 〉 leaching temperature 〉 current density. The optimum conditions were as follows： 1.10：1 mass ratio of ferrous sulfate heptahydrate to pyrolusite, 0.9：1 mass ratio of sulfuric acid to pyrolusite, liquid-to-solid ratio of 0.7：1, current density of 947 A/m^2, leaching time of 180 min, and leaching temperature of 73°C. Under these conditions, the predicted leaching efficiency for Mn was 94.1%; the obtained experimental result was 95.7%, which confirmed the validity of the model.
基金financially supported by the National Natural Science Foundation of China(Nos.51204054 and 51574084)the Fundamental Research Funds for the Central Universities of China(No.N150204009)the National Basic Research Priorities Program of China(No.2014CB643405)
文摘An orthogonal test was used to optimize the reaction conditions of roasting zinc oxide ore using（NH_4）_2SO_4. The optimized reaction conditions are defined as an（NH_4）_2SO_4/zinc molar ratio of 1.4：1, a roasting temperature of 440°C, and a thermostatic time of 60 min. The molar ratio of（NH_4）_2SO_4/zinc is the most predominant factor and the roasting temperature is the second significant factor that governs the zinc extraction. Thermogravimetric-differential thermal analysis was used for（NH_4）_2SO_4 and zinc mixed in a molar ratio of 1.4：1 at the heating rates of 5, 10, 15, and 20 K·min-1. Two strong endothermic peaks indicate that the complex chemical reactions occur at approximately 290°C and 400°C. XRD analysis was employed to examine the transformations of mineral phases during roasting process. Kinetic parameters, including reaction apparent activation energy, reaction order, and frequency factor, were calculated by the Doyle-Ozawa and Kissinger methods. Corresponding to the two endothermic peaks, the kinetic equations were obtained.
