N-2000 is an admixture for concrete,with a low slump loss,high range water-reducing ratio and long-time retarding.The N-2000 is made up of naphthalene-sulfonic-maldehyde polycondensation(NSMP)and ATMP.Its characterist...N-2000 is an admixture for concrete,with a low slump loss,high range water-reducing ratio and long-time retarding.The N-2000 is made up of naphthalene-sulfonic-maldehyde polycondensation(NSMP)and ATMP.Its characteristic results from the synergistic effects of NSMP and ATMP.The results show that when 0.7%-1.2%of N-2000 is added to concrete(by mass of cement),the water reducing ratio is up to 20%-30%,and the slump of fresh concrete can be retained for 2 hours without significant loss.N-2000 can not only improve the workability of fresh concrete but also increase the strength of the hardened concrete,especially early strength.It is also proved to have a good compatibility with various cements.展开更多
Influences of admixtures on the workability and strength of high performance concrete （HPC） are in- vestigated. The types of investigated admixtures include naphthalene series high range water reducing agent, polyca...Influences of admixtures on the workability and strength of high performance concrete （HPC） are in- vestigated. The types of investigated admixtures include naphthalene series high range water reducing agent, polycarboxlic series high range water reduce agent and sodium sulfate hardening accelerating agent. Two kinds of curing condition, namely steam curing condition and standard curing condition, are adopted. The result shows that HPC, added with polycarboxlic series of high performance water reducer, has high workability and strength, while sodium sulfate accelerating agent causes poor workability and low strength. Thus for vapor-cured HPC and its formulations, naphthalene series high range water reducing agent with less sodium sulfate should be given pri- ority. Therefore, the differences of curing conditions should be considered when selecting HPC admixtures.展开更多
Effects of polycarboxylate type admixture（PCA）on calcium monocarboaluminate hydrate（AFmc）formation in hydrated cement paste containing limestone filler（LF）are investigated by the Fourier transform infrared spect...Effects of polycarboxylate type admixture（PCA）on calcium monocarboaluminate hydrate（AFmc）formation in hydrated cement paste containing limestone filler（LF）are investigated by the Fourier transform infrared spectroscopy（FTIR）,the scanning electron microscopy（SEM）,the derivative thermogravimetric（DTG）analysis and the adsorption amount measurement.Experimental results indicate that AFmc forms during the initial hydration period of cement as early as 15 min.It is found that PCA accelerates the early age AFmc formation and enhances cement hydration by promoting C4AF hydration at the early age,and,as a consequence,the iron associated AFmc phase forms more readily.The phenomenon is not observed when PCA is replaced by a naphthalene formaldehyde sulphonate condensate water reducer.Compatibility between PCA and cement is modified due to the presence of AFmc along with ettringite（AFt）,which results in a less adsorption amount of PCA on the surface of cement minerals.As a kind of high-range water reducer,PCA may be the preferred choice for concrete containing LF.展开更多
A new report from Jeanologia highlights theurgent need for the denim industry to adopt saferalternatives to harmful chemicals.The study alsostresses reducing excessive water use in garmentfinishing.The report,compiled...A new report from Jeanologia highlights theurgent need for the denim industry to adopt saferalternatives to harmful chemicals.The study alsostresses reducing excessive water use in garmentfinishing.The report,compiled in 2024,analyzed datafrom more than ll5,000 dentm finishing processes.lt found that 24%of denim finishing processes stilluse hazardous chemicals,posing risks to both theenvironment and the health of workers.展开更多
The permeability,alkali silica reaction,workability and strength of GHPC(green high performance concrete) were studied in this paper.The results show that GHPC has an excellent durability and the effects of mass rat...The permeability,alkali silica reaction,workability and strength of GHPC(green high performance concrete) were studied in this paper.The results show that GHPC has an excellent durability and the effects of mass ratio of flyash to high calcium slag,water binder ratio,content of water reducer,and crushed coarse aggregate type on the workability and strength of GHPC were considerably evident.A new path for the concretes continuous development was put forward.展开更多
In cluster-based MOF materials,although clusters with open metal sites(OMSs)play a critical role in separation processes,excessively strong OMSs can lead to significant co-adsorption with the counterpart gases and res...In cluster-based MOF materials,although clusters with open metal sites(OMSs)play a critical role in separation processes,excessively strong OMSs can lead to significant co-adsorption with the counterpart gases and result in reduced selectivity.Coordinated water molecules can not only result in atomic-level differences in pore size but also significantly affect the binding forces between the host frameworks and vip molecules.Herein,we report a methyl-modified heptanuclear cluster-based MOF,Ni_(7)Me,constructed from inexpensive organic linkers under pure water conditions.Two vip-free materials,Ni_(7)Me-80(with coordinated water)and Ni_(7)Me-200(with OMSs),were synthesized to investigate the separation properties and mechanisms for C_(2)H_(2)/C_(2)H_(4) and C_(3)H_(6)/C_(3)H_(8) mixtures.Dynamic breakthrough tests showed that both Ni_(7)Me-80 and Ni_(7)Me-200 could achieve clean separation of binary C_(2)H_(2)/C_(2)H_(4) mixtures(5/95 v/v),yielding high-purity C_(2)H_(4)(>99.9%).Grand canonical Monte Carlo(GCMC)simulations revealed that the enhanced adsorption and separation performance of Ni_(7)Me-200,compared to Ni_(7)Me-80,is primarily due to differences in the interaction forces between C_(2) molecules and the framework,independent of the OMSs.Notably,Ni_(7)Me-80 exhibited thermodynamically driven adsorption for C_(3)H_(6),while showing kinetic behaviour for C_(3)H_(8) adsorption.This unique property enabled effective separation of C_(3)H_(6) and C_(3)H_(8),as demonstrated by dynamic permeation tests.Stability tests further showed that Ni_(7)Me has exceptional air and boiling water stability.展开更多
Two different kinds of black liquor from the papermaking industry were treated by acidification and reuse. The experimental parameters and conditions were discussed in detail. The experimental results indicated that t...Two different kinds of black liquor from the papermaking industry were treated by acidification and reuse. The experimental parameters and conditions were discussed in detail. The experimental results indicated that the treatment process mentioned in this article is an effective process for the treatment of black liquor from the papermaking industry. By the treatment, the solid materials in black liquor are transferred into two by products and the other components are reused or evaporated. Thus, no wastewater except some condensation water would be discharged in pulping process and the problem of pollution of black liquor would be effectively solved.展开更多
基金Key Science and Technology Development Fund Project of Hubei Province.China(No.941PO106).
文摘N-2000 is an admixture for concrete,with a low slump loss,high range water-reducing ratio and long-time retarding.The N-2000 is made up of naphthalene-sulfonic-maldehyde polycondensation(NSMP)and ATMP.Its characteristic results from the synergistic effects of NSMP and ATMP.The results show that when 0.7%-1.2%of N-2000 is added to concrete(by mass of cement),the water reducing ratio is up to 20%-30%,and the slump of fresh concrete can be retained for 2 hours without significant loss.N-2000 can not only improve the workability of fresh concrete but also increase the strength of the hardened concrete,especially early strength.It is also proved to have a good compatibility with various cements.
基金Supported by the National Basic Research Programe of China("973"Program)(2009CB623203)the Construction Department of Zhejiang Province Foundation(1006)+1 种基金the Education Department of Zhejiang Province Foundation(Y200909029)the Doctoral Innovation Foundation of Nanjing University of Aeronautics andAstronautics(BCXJ07-04)~~
文摘Influences of admixtures on the workability and strength of high performance concrete （HPC） are in- vestigated. The types of investigated admixtures include naphthalene series high range water reducing agent, polycarboxlic series high range water reduce agent and sodium sulfate hardening accelerating agent. Two kinds of curing condition, namely steam curing condition and standard curing condition, are adopted. The result shows that HPC, added with polycarboxlic series of high performance water reducer, has high workability and strength, while sodium sulfate accelerating agent causes poor workability and low strength. Thus for vapor-cured HPC and its formulations, naphthalene series high range water reducing agent with less sodium sulfate should be given pri- ority. Therefore, the differences of curing conditions should be considered when selecting HPC admixtures.
基金The Natural Science Foundation of Jiangsu Province(No.BK2009712)the National Construction Research Project(No.2009-K4-9)
文摘Effects of polycarboxylate type admixture（PCA）on calcium monocarboaluminate hydrate（AFmc）formation in hydrated cement paste containing limestone filler（LF）are investigated by the Fourier transform infrared spectroscopy（FTIR）,the scanning electron microscopy（SEM）,the derivative thermogravimetric（DTG）analysis and the adsorption amount measurement.Experimental results indicate that AFmc forms during the initial hydration period of cement as early as 15 min.It is found that PCA accelerates the early age AFmc formation and enhances cement hydration by promoting C4AF hydration at the early age,and,as a consequence,the iron associated AFmc phase forms more readily.The phenomenon is not observed when PCA is replaced by a naphthalene formaldehyde sulphonate condensate water reducer.Compatibility between PCA and cement is modified due to the presence of AFmc along with ettringite（AFt）,which results in a less adsorption amount of PCA on the surface of cement minerals.As a kind of high-range water reducer,PCA may be the preferred choice for concrete containing LF.
文摘A new report from Jeanologia highlights theurgent need for the denim industry to adopt saferalternatives to harmful chemicals.The study alsostresses reducing excessive water use in garmentfinishing.The report,compiled in 2024,analyzed datafrom more than ll5,000 dentm finishing processes.lt found that 24%of denim finishing processes stilluse hazardous chemicals,posing risks to both theenvironment and the health of workers.
文摘The permeability,alkali silica reaction,workability and strength of GHPC(green high performance concrete) were studied in this paper.The results show that GHPC has an excellent durability and the effects of mass ratio of flyash to high calcium slag,water binder ratio,content of water reducer,and crushed coarse aggregate type on the workability and strength of GHPC were considerably evident.A new path for the concretes continuous development was put forward.
基金the Natural Science Foundation of Ningbo(2022J101)This work was carried out with the support of the Shanghai Synchrotron Radiation Facility,instrument BL17B.
文摘In cluster-based MOF materials,although clusters with open metal sites(OMSs)play a critical role in separation processes,excessively strong OMSs can lead to significant co-adsorption with the counterpart gases and result in reduced selectivity.Coordinated water molecules can not only result in atomic-level differences in pore size but also significantly affect the binding forces between the host frameworks and vip molecules.Herein,we report a methyl-modified heptanuclear cluster-based MOF,Ni_(7)Me,constructed from inexpensive organic linkers under pure water conditions.Two vip-free materials,Ni_(7)Me-80(with coordinated water)and Ni_(7)Me-200(with OMSs),were synthesized to investigate the separation properties and mechanisms for C_(2)H_(2)/C_(2)H_(4) and C_(3)H_(6)/C_(3)H_(8) mixtures.Dynamic breakthrough tests showed that both Ni_(7)Me-80 and Ni_(7)Me-200 could achieve clean separation of binary C_(2)H_(2)/C_(2)H_(4) mixtures(5/95 v/v),yielding high-purity C_(2)H_(4)(>99.9%).Grand canonical Monte Carlo(GCMC)simulations revealed that the enhanced adsorption and separation performance of Ni_(7)Me-200,compared to Ni_(7)Me-80,is primarily due to differences in the interaction forces between C_(2) molecules and the framework,independent of the OMSs.Notably,Ni_(7)Me-80 exhibited thermodynamically driven adsorption for C_(3)H_(6),while showing kinetic behaviour for C_(3)H_(8) adsorption.This unique property enabled effective separation of C_(3)H_(6) and C_(3)H_(8),as demonstrated by dynamic permeation tests.Stability tests further showed that Ni_(7)Me has exceptional air and boiling water stability.
文摘Two different kinds of black liquor from the papermaking industry were treated by acidification and reuse. The experimental parameters and conditions were discussed in detail. The experimental results indicated that the treatment process mentioned in this article is an effective process for the treatment of black liquor from the papermaking industry. By the treatment, the solid materials in black liquor are transferred into two by products and the other components are reused or evaporated. Thus, no wastewater except some condensation water would be discharged in pulping process and the problem of pollution of black liquor would be effectively solved.
