Effects of organosilane-modified PCE (OS-PCE) on the fluidity and the hydration properties of cement-fly ash (FA) composite binder were systematically analyzed.The experimental results show that OS-PCE possesses respe...Effects of organosilane-modified PCE (OS-PCE) on the fluidity and the hydration properties of cement-fly ash (FA) composite binder were systematically analyzed.The experimental results show that OS-PCE possesses respectively 36.98% and 36.67% higher saturated adsorption amount on cement and FA,in comparison with ordinary PCE,and can contribute to higher fluidity of cement-FA composite binder.The addition of OS-PCE retards hydration process of cement-FA composite binder proportionally with the dosage of OS-PCE,but promotes the hydration kinetics of the composite binder.The reactivity enhancement is attributed to the well-dispersed FA by OS-PCE,which provides more nucleation sites for the reaction of heterogeneous C-S-H and enhances the contact with water to react with CH forming pozzolanic C-S-H.Well-distributed hydration products are exhibited in the hardened binder added with OS-PCE,with a large number of hydrated gels uniformly fill in the pores and gaps,which improves the compaction of the hardened structure.展开更多
Background:This study aimed to investigate the hydration properties of different-source fibrous materials by com-paring their water-binding capacity(WBC),water swelling capacity(WSC),viscosity,and in vivo effects of s...Background:This study aimed to investigate the hydration properties of different-source fibrous materials by com-paring their water-binding capacity(WBC),water swelling capacity(WSC),viscosity,and in vivo effects of selected samples on growth performance,nutrient digestibility,diarrhea,and intestinal health in weaned piglets.Methods:A total of 13 commercially available fibrous materials were first compared in chemical composition and in vitro hydration property.Subsequently,40 weaned piglets were randomized to five experimental dietary groups(8 piglets per group):control diet(a basal diet without dietary fiber,CON),basal diet supplemented with 5%microcrys-talline cellulose(MCC),5%wheat bran(WB),5%Moringa oleifera leaf powder(MOLP),or 5%sugar beet pulp(SBP),fol-lowed by analyzing their growth performance and diarrhea rate in a 28-d experiment.After the feeding experiment,anaesthetized piglets were killed,and their intestinal and colon content or plasma samples were analyzed in nutrient digestibility,intestinal morphology,intestinal barrier,short-chain fatty acids(SCFAs),and bacterial population.Results:In vitro studies showed low hydration properties for WB and MCC,while medium hydration properties for MOLP and SBP.In vivo studies indicated that compared with medium hydration property groups,low hydration prop-erty groups showed(1)exacerbated diarrhea,impaired intestinal health,and reduced apparent fecal digestibility of dry matter,gross energy,acid detergent fiber,and neutral detergent fiber;(2)decreased SCFAs concentration and rela-tive levels of Lactobacillus and Bifidobacterium,but increased levels of Escherichia coli and Brachyspira hyodysenteriae in colon contents.Additionally,SBP showed optimal performance in reducing diarrhea and increasing SCFAs produc-tion.Correlation analysis revealed a positive correlation of fiber hydration properties with in vitro SCFAs production,and diarrhea index and nutrient digestibility were negatively and positively correlated with SCFAs levels in the colon contents of weaned piglets,respectively.Conclusions:Different-source dietary fibers varied in their hydration properties and impacts on diarrhea,microbial composition and SCFAs production in weaned piglets.WB and MCC could exacerbate diarrhea and impair nutrient digestibility,probably because their low hydration properties were detrimental to gut microbial homeostasis and fermentation.Our findings provide new ideas for rational use of fiber resources in weaned piglets.展开更多
PrBa_(0.5)Sr_(0.5)Co_(1.5)Fe_(0.5)O_(5+δ)(PrBSCF) has attracted much research interest as a potential triple ionic and electronic conductor(TIEC) electrode for protonic ceramic fuel cells(PCFCs). The chemical formula...PrBa_(0.5)Sr_(0.5)Co_(1.5)Fe_(0.5)O_(5+δ)(PrBSCF) has attracted much research interest as a potential triple ionic and electronic conductor(TIEC) electrode for protonic ceramic fuel cells(PCFCs). The chemical formula for Pr BSCF is AA'B_(2)O_(5+δ), with Pr(A-site) and Ba/Sr(A'-site) alternately stacked along the c-axis. Due to these structural features, the bulk oxygen ion diffusivity is significantly enhanced through the disorder-free channels in the PrO layer;thus, the A site cations(lanthanide ions) play a pivotal role in determining the overall electrochemical properties of layered perovskites. Consequently, previous research has predominantly focused on the electrical properties and oxygen bulk/surface kinetics of Ln cation effects,whereas the hydration properties for PCFC systems remain unidentified. Here, we thoroughly examined the proton uptake behavior and thermodynamic parameters for the hydration reaction to conclusively determine the changes in the electrochemical performances depending on LnBa_(0.5)Sr_(0.5)Co_(1.5)Fe_(0.5)O_(5+δ)(LnBSCF,Ln=Pr, Nd, and Gd) cathodes. At 500 ℃, the quantitative proton concentration of PrBSCF was 2.04 mol% and progressively decreased as the Ln cation size decreased. Similarly, the Gibbs free energy indicated that less energy was required for the formation of protonic defects in the order of Pr BSCF < Nd BSCF < Gd BSCF. To elucidate the close relationship between hydration properties and electrochemical performances in LnBSCF cathodes, PCFC single cell measurements and analysis of the distribution of relaxation time were further investigated.展开更多
The effect of the borax content and magnesia to phosphate ratio（M/P） on the hydration properties of the magnesium potassium phosphate cement（MKPC） with large volume of fly ash was investigated, and a five-hydratio...The effect of the borax content and magnesia to phosphate ratio（M/P） on the hydration properties of the magnesium potassium phosphate cement（MKPC） with large volume of fly ash was investigated, and a five-hydration-stage for MKPCs was proposed. The results show that MKPC sets rapidly with less than 8% of borax, which is unfavorable to the application of MKPC on construction. Adding more than 8%（including 8%） of borax results in a secondary hydration peak for MKPC, in which the process of hydration can be divided into five stages, namely, pre-induction period, induction period, acceleration period, deceleration period and stable period. M/P ratios could not change the multi-step reactive stages but higher M/P ratios could accelerate the hydration. Borax tends to impact the formation of Mg-containing hydrated products.展开更多
Graphene oxide(GO)as a new nano-enhancer in cement-based materials has gained wide attention.However,GO is easy to aggregate in alkaline cement mortar with poor dispersibility.This hinders its application in practical...Graphene oxide(GO)as a new nano-enhancer in cement-based materials has gained wide attention.However,GO is easy to aggregate in alkaline cement mortar with poor dispersibility.This hinders its application in practical infrastructure construction.In this work,GO-M18 polycarboxylate compound superplasticizer(GM)were obtained by compounding the M18 polycarboxylate superplasticizer with GO solution at different mass ratios.The dispersion of GM in alkaline solution was systematically studied.The phases and functional groups of GM were characterized by XRD and FTIR.The effects of GM on the cement mortar hydration and the formation of microstructure were investigated by measuring the heat of hydration,MIP,TG/DSC,and SEM.The results show that the long-chain structure of the M18 polycarboxylate superplasticizer can increase the interlayer spacing of GO and weaken the force between GO sheets.The modified GO can be uniformly dispersed in the cement slurry.GM can accelerate the early hydration process of cement,which can increase the content of Ca(OH)2 and decrease the grain size.It can optimize the pore size distribution of cement-based materials,increase the density of harmless and less harmful pores,thereby improving mechanical properties.Such methods can transform traditional cement-based materials into stronger,more durable composites,which prolong the life of cement-based materials and reduce the amount of cement used for later maintenance.This provides an idea for achieving sustainability goals in civil engineering.展开更多
Pitch and tar bonded dolomite bricks are extensively used in ladles and converters for long time because of their superior properties such as. steel melt refining, easy production as well as low production cost. Recen...Pitch and tar bonded dolomite bricks are extensively used in ladles and converters for long time because of their superior properties such as. steel melt refining, easy production as well as low production cost. Recently, resin bonded dolomite bricks are presented for using in steel plants. Generally, quality and final cost of steels are affected by properties of refractories especially dolomite bricks. Therefore, recognition of influence parameters on dolomite refractory properties is very important. In this study, the effects of tar and resin as bonding systems, and addition of graphite （ 2wt% ） on the properties of dolomite refractory bricks have been investigated. Properties such as ： density and porosity, cold crushing strength, hydration time and depth of slag penetration have been studied. Results show that the bonding sys- tems and graphite have a great effect on the mentioned properties especially cold crushing strength and hydra- tion time. In addition to their low rate of pollution, resin bonded dolomite bricks show higher performance with proper technical specifications.展开更多
A molecular modified PCE-type GA was self-synthesized,and the grindability concerning grinding duration and particle size distribution of ground cement was evaluated.Setting time,flowability,hydration heat,mechanical ...A molecular modified PCE-type GA was self-synthesized,and the grindability concerning grinding duration and particle size distribution of ground cement was evaluated.Setting time,flowability,hydration heat,mechanical properties and microstructure of the ground cement were also investigated.The results show that:PCE-type GA is effective in cement grinding.With 0.03%PCE-type GA added into cement clinker,the Blain surface area reaches to the highest at every ten minutes,and the volume percent of cement particles with size of(0-32μm)reaches the highest.Excessive amount of PCE-type GA seems to impair the grinding efficiency.The grinding efficiency promotes cement fineness and hence contributes to the cement hydration degree as well as improves the mechanical properties.展开更多
The objective of this study was to assess the feasibility of using the plant-source polymer of the matcha powder as a composite admixture for hemihydrate gypsum. Hemihydrate gypsum was mixed with different contents of...The objective of this study was to assess the feasibility of using the plant-source polymer of the matcha powder as a composite admixture for hemihydrate gypsum. Hemihydrate gypsum was mixed with different contents of matcha powder, and then the water requirement for the normal consistency, setting times, density, strength, hydration and microstructure of the hardened mixture were evaluated. The experimental results showed that it increased the water requirement for the normal consistency, and it regulated the setting times and reduced the density. Hemihydrate gypsum with more matcha powder had the higher water requirement, longer setting times and lower density. Less than 1% matcha powder had slight impact on the strength of hardened paste, but more than 1% matcha powder had a remarkable one. Matcha powder changed the hydration process and prolonged the induction and acceleration period. Small needlelike crystals were transformed into longer, larger and thicker ones as more matcha powder was mixed. This case is closely related to the prolongation of the induction and acceleration period. Besides, more and larger pores were observed in the hardened paste with more matcha powder. It is attributed to the appearances of the tea polyphenol in matcha powder and the larger and longer crystal morphology in hardened paste as well as the high water requirement for the normal consistency. These results are important to the application of matcha powder as a composite admixture for the hemihydrate gypsum as well as the prosperity and development of the tea industry.展开更多
基金Funded by the Natural Science Foundation of China(51808369)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(18KJB560016)+4 种基金the Opening Project of State Key Laboratory of Green Building Materials(YA-615)the State Key Laboratory of Silicate Building Materials(SYSJJ2018-09)Hubei Key Laboratory of Water System Science for Sponge City Construction(2019-01)the Construction System Science and Technology Project of Jiangsu Province(2018ZD049)the Natural Science Foundation of Suzhou University of Science and Technology(XKQ2018009)。
文摘Effects of organosilane-modified PCE (OS-PCE) on the fluidity and the hydration properties of cement-fly ash (FA) composite binder were systematically analyzed.The experimental results show that OS-PCE possesses respectively 36.98% and 36.67% higher saturated adsorption amount on cement and FA,in comparison with ordinary PCE,and can contribute to higher fluidity of cement-FA composite binder.The addition of OS-PCE retards hydration process of cement-FA composite binder proportionally with the dosage of OS-PCE,but promotes the hydration kinetics of the composite binder.The reactivity enhancement is attributed to the well-dispersed FA by OS-PCE,which provides more nucleation sites for the reaction of heterogeneous C-S-H and enhances the contact with water to react with CH forming pozzolanic C-S-H.Well-distributed hydration products are exhibited in the hardened binder added with OS-PCE,with a large number of hydrated gels uniformly fill in the pores and gaps,which improves the compaction of the hardened structure.
基金funded by Project of National Natural Science Foundation of China(No.32172744 and 31902165)Natural Science Foundation of Guangdong Province(2021A1515012116)Natural Science Foundation of Guangzhou City(202102080090).
文摘Background:This study aimed to investigate the hydration properties of different-source fibrous materials by com-paring their water-binding capacity(WBC),water swelling capacity(WSC),viscosity,and in vivo effects of selected samples on growth performance,nutrient digestibility,diarrhea,and intestinal health in weaned piglets.Methods:A total of 13 commercially available fibrous materials were first compared in chemical composition and in vitro hydration property.Subsequently,40 weaned piglets were randomized to five experimental dietary groups(8 piglets per group):control diet(a basal diet without dietary fiber,CON),basal diet supplemented with 5%microcrys-talline cellulose(MCC),5%wheat bran(WB),5%Moringa oleifera leaf powder(MOLP),or 5%sugar beet pulp(SBP),fol-lowed by analyzing their growth performance and diarrhea rate in a 28-d experiment.After the feeding experiment,anaesthetized piglets were killed,and their intestinal and colon content or plasma samples were analyzed in nutrient digestibility,intestinal morphology,intestinal barrier,short-chain fatty acids(SCFAs),and bacterial population.Results:In vitro studies showed low hydration properties for WB and MCC,while medium hydration properties for MOLP and SBP.In vivo studies indicated that compared with medium hydration property groups,low hydration prop-erty groups showed(1)exacerbated diarrhea,impaired intestinal health,and reduced apparent fecal digestibility of dry matter,gross energy,acid detergent fiber,and neutral detergent fiber;(2)decreased SCFAs concentration and rela-tive levels of Lactobacillus and Bifidobacterium,but increased levels of Escherichia coli and Brachyspira hyodysenteriae in colon contents.Additionally,SBP showed optimal performance in reducing diarrhea and increasing SCFAs produc-tion.Correlation analysis revealed a positive correlation of fiber hydration properties with in vitro SCFAs production,and diarrhea index and nutrient digestibility were negatively and positively correlated with SCFAs levels in the colon contents of weaned piglets,respectively.Conclusions:Different-source dietary fibers varied in their hydration properties and impacts on diarrhea,microbial composition and SCFAs production in weaned piglets.WB and MCC could exacerbate diarrhea and impair nutrient digestibility,probably because their low hydration properties were detrimental to gut microbial homeostasis and fermentation.Our findings provide new ideas for rational use of fiber resources in weaned piglets.
基金supported by the National Research Foundation (NRF) grant funded by the Korea government (NRF2022R1C1C1007619, NRF-2021M3H4A1A01002921, NRF2021M3I3A1084292)supported by the KIST Institutional Program (Project No. 2E32592-23-069)。
文摘PrBa_(0.5)Sr_(0.5)Co_(1.5)Fe_(0.5)O_(5+δ)(PrBSCF) has attracted much research interest as a potential triple ionic and electronic conductor(TIEC) electrode for protonic ceramic fuel cells(PCFCs). The chemical formula for Pr BSCF is AA'B_(2)O_(5+δ), with Pr(A-site) and Ba/Sr(A'-site) alternately stacked along the c-axis. Due to these structural features, the bulk oxygen ion diffusivity is significantly enhanced through the disorder-free channels in the PrO layer;thus, the A site cations(lanthanide ions) play a pivotal role in determining the overall electrochemical properties of layered perovskites. Consequently, previous research has predominantly focused on the electrical properties and oxygen bulk/surface kinetics of Ln cation effects,whereas the hydration properties for PCFC systems remain unidentified. Here, we thoroughly examined the proton uptake behavior and thermodynamic parameters for the hydration reaction to conclusively determine the changes in the electrochemical performances depending on LnBa_(0.5)Sr_(0.5)Co_(1.5)Fe_(0.5)O_(5+δ)(LnBSCF,Ln=Pr, Nd, and Gd) cathodes. At 500 ℃, the quantitative proton concentration of PrBSCF was 2.04 mol% and progressively decreased as the Ln cation size decreased. Similarly, the Gibbs free energy indicated that less energy was required for the formation of protonic defects in the order of Pr BSCF < Nd BSCF < Gd BSCF. To elucidate the close relationship between hydration properties and electrochemical performances in LnBSCF cathodes, PCFC single cell measurements and analysis of the distribution of relaxation time were further investigated.
基金Funded by the National Natural Science Foundation of China(No.51472168)Natural Scientific Foundation of Liaoning Province(No.201602646)Open Fund from Liaoning Key Laboratory of Advanced Processing Technology for Metal Materials,Shenyang Ligong University,the Postdoctoral Research Foundation of Shenyang Ligong University
文摘The effect of the borax content and magnesia to phosphate ratio（M/P） on the hydration properties of the magnesium potassium phosphate cement（MKPC） with large volume of fly ash was investigated, and a five-hydration-stage for MKPCs was proposed. The results show that MKPC sets rapidly with less than 8% of borax, which is unfavorable to the application of MKPC on construction. Adding more than 8%（including 8%） of borax results in a secondary hydration peak for MKPC, in which the process of hydration can be divided into five stages, namely, pre-induction period, induction period, acceleration period, deceleration period and stable period. M/P ratios could not change the multi-step reactive stages but higher M/P ratios could accelerate the hydration. Borax tends to impact the formation of Mg-containing hydrated products.
基金funded by the National Natural Science Foundation of China(No.51872137)and Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘Graphene oxide(GO)as a new nano-enhancer in cement-based materials has gained wide attention.However,GO is easy to aggregate in alkaline cement mortar with poor dispersibility.This hinders its application in practical infrastructure construction.In this work,GO-M18 polycarboxylate compound superplasticizer(GM)were obtained by compounding the M18 polycarboxylate superplasticizer with GO solution at different mass ratios.The dispersion of GM in alkaline solution was systematically studied.The phases and functional groups of GM were characterized by XRD and FTIR.The effects of GM on the cement mortar hydration and the formation of microstructure were investigated by measuring the heat of hydration,MIP,TG/DSC,and SEM.The results show that the long-chain structure of the M18 polycarboxylate superplasticizer can increase the interlayer spacing of GO and weaken the force between GO sheets.The modified GO can be uniformly dispersed in the cement slurry.GM can accelerate the early hydration process of cement,which can increase the content of Ca(OH)2 and decrease the grain size.It can optimize the pore size distribution of cement-based materials,increase the density of harmless and less harmful pores,thereby improving mechanical properties.Such methods can transform traditional cement-based materials into stronger,more durable composites,which prolong the life of cement-based materials and reduce the amount of cement used for later maintenance.This provides an idea for achieving sustainability goals in civil engineering.
文摘Pitch and tar bonded dolomite bricks are extensively used in ladles and converters for long time because of their superior properties such as. steel melt refining, easy production as well as low production cost. Recently, resin bonded dolomite bricks are presented for using in steel plants. Generally, quality and final cost of steels are affected by properties of refractories especially dolomite bricks. Therefore, recognition of influence parameters on dolomite refractory properties is very important. In this study, the effects of tar and resin as bonding systems, and addition of graphite （ 2wt% ） on the properties of dolomite refractory bricks have been investigated. Properties such as ： density and porosity, cold crushing strength, hydration time and depth of slag penetration have been studied. Results show that the bonding sys- tems and graphite have a great effect on the mentioned properties especially cold crushing strength and hydra- tion time. In addition to their low rate of pollution, resin bonded dolomite bricks show higher performance with proper technical specifications.
基金Funded by the National Natural Science Foundation of China(No.51808369)Hubei Key Laboratory of Water System Science for Sponge City Construction(No.2019-01)。
文摘A molecular modified PCE-type GA was self-synthesized,and the grindability concerning grinding duration and particle size distribution of ground cement was evaluated.Setting time,flowability,hydration heat,mechanical properties and microstructure of the ground cement were also investigated.The results show that:PCE-type GA is effective in cement grinding.With 0.03%PCE-type GA added into cement clinker,the Blain surface area reaches to the highest at every ten minutes,and the volume percent of cement particles with size of(0-32μm)reaches the highest.Excessive amount of PCE-type GA seems to impair the grinding efficiency.The grinding efficiency promotes cement fineness and hence contributes to the cement hydration degree as well as improves the mechanical properties.
基金Funded by the National Natural Science Foundation of China(Nos.51678442,51578412,51478348,51508404,51878480,and 51878479)the National High-speed Train Union Fund(U1534207)+1 种基金Key Project of the Shanghai Committee of Science and Technology(No.15DZ1205003)the Fundamental Research Funds for the Central Universities
文摘The objective of this study was to assess the feasibility of using the plant-source polymer of the matcha powder as a composite admixture for hemihydrate gypsum. Hemihydrate gypsum was mixed with different contents of matcha powder, and then the water requirement for the normal consistency, setting times, density, strength, hydration and microstructure of the hardened mixture were evaluated. The experimental results showed that it increased the water requirement for the normal consistency, and it regulated the setting times and reduced the density. Hemihydrate gypsum with more matcha powder had the higher water requirement, longer setting times and lower density. Less than 1% matcha powder had slight impact on the strength of hardened paste, but more than 1% matcha powder had a remarkable one. Matcha powder changed the hydration process and prolonged the induction and acceleration period. Small needlelike crystals were transformed into longer, larger and thicker ones as more matcha powder was mixed. This case is closely related to the prolongation of the induction and acceleration period. Besides, more and larger pores were observed in the hardened paste with more matcha powder. It is attributed to the appearances of the tea polyphenol in matcha powder and the larger and longer crystal morphology in hardened paste as well as the high water requirement for the normal consistency. These results are important to the application of matcha powder as a composite admixture for the hemihydrate gypsum as well as the prosperity and development of the tea industry.
