Pervaporation desalination by highly hydrophilic materials such as poly(vinyl alcohol)(PVA)based separation membrane is a burgeoning technology of late years.However,the improvement of membrane flux in pervaporation d...Pervaporation desalination by highly hydrophilic materials such as poly(vinyl alcohol)(PVA)based separation membrane is a burgeoning technology of late years.However,the improvement of membrane flux in pervaporation desalination has been a difficult task.Here,a novel hybrid membrane with doped graphene oxide quantum dots(GOQDs)which is rich in hydrophilic groups and small size into the matrix of PVA was prepared to improve the membrane flux.The membranes structures were described by field emission scanning electron microscopy(FESEM),atomic force microscopy(AFM),Fourier transform infrared(FT-IR),differential scanning calorimetry(DSC),thermogravimetric analysis(TGA)and X-ray diffraction(XRD).And more,Water contact angle,swelling degree,and pervaporation properties were carried out to explore the effect of GOQDs in PVA matrix.In addition,GOQDs content in the hybrid membrane,NaCl concentration,and feed temperature were investigated accordingly.Moreover,the hydrogen bonds between PVA chains were weakened by the interaction between GOQDs and PVA chains.Significantly,the hybrid membrane with optimized doped GOQDs content,200 mg·L^(-1),displays a high membrane flux of 17.09 kg·m^(-2)·h^(-1)and the salt rejection is consistently greater than 99.6%.展开更多
The tribological behavior of 316L stainless steel/CoCrMo alloy contacts under aqueous lubrication was investigated in this work.Three types of microgels including poly(N-isopropylacrylamide)(PNIPAM),polyacrylic acid(P...The tribological behavior of 316L stainless steel/CoCrMo alloy contacts under aqueous lubrication was investigated in this work.Three types of microgels including poly(N-isopropylacrylamide)(PNIPAM),polyacrylic acid(PAA),and poly(N-isopropylacrylamide-co-acrylic acid)(PNIPAM-co-PAA)were prepared and used as lubricant additives in aqueous solutions.Tribological tests were conducted using a ball-on-disk reciprocating tribometer,over a range of temperatures,pH,and concentrations of the microgels.The PNIPAM-co-PAA microgels were proven to have excellent anti-friction and anti-wear properties,depending on the temperature and pH values of the solutions.The maximum friction coefficient coincided with the lower critical solution temperature of the PNIPAM-co-PAA microgels at 32°C.At the same time,the friction coefficient increased with the increase in pH value of the lubricant solution with the PNIPAM-co-PAA microgels.The unique thermal-and pH-sensitive properties of the PNIPAM-co-PAA microgels provided a new strategy for controlling the friction and wear of steel/CoCrMo alloy contacts under aqueous lubrication.展开更多
Introduction:The swift advancement of biotechnology has presented both opportunities and challenges to our society,thrusting biosafety to the forefront of concern.Consequently,the evaluation of rescue capabilities in ...Introduction:The swift advancement of biotechnology has presented both opportunities and challenges to our society,thrusting biosafety to the forefront of concern.Consequently,the evaluation of rescue capabilities in the event of a bioterrorism incident becomes of paramount importance.Currently,there is a notable absence of specific measurement criteria and a comprehensive evaluation system.This paper aims to establish a systematic approach towards assessing emergency response capabilities in the context of bioterrorism incidents.Methods:We employed an enhanced Delphi methodology to establish an index evaluation framework.Subsequently,the weight of the judgment matrix was ascertained via the application of the fuzzy comprehensive evaluation approach.This led to the creation of a fuzzy comprehensive evaluation model for bioterrorism rescue capability.Results:A modified Delphi study was conducted involving 11 experts across two rounds,achieving a response rate of 100%.The Kendall coordination coefficients recorded in the first and second rounds were 0.303 and 0.632,respectively(P<0.05).Upon comprehensive analysis involving score,coefficient of variation,and full score ratio,we distinguished five primary indicators and 25 secondary indicators.Subsequently,an evaluation model was developed based on the Analytic Hierarchy Process(AHP)tailored to assess the response to a rescue from bioterrorism.Discussion:The expert panel confirmed consensus on all aspects of the model,validating its comprehensive content.The succeeding course of action involves converting the assessment model to a measurable scale,affirming its functionality,and implementing it in practical evaluation tasks to further enhance the capabilities of the biological incident rescue team.展开更多
In the present work,two types of novel nano additives,titanium sulfonate ligand/black phosphorus(TiLi/BP)and titanium dioxide/black phosphorus(TiCVBP)nanocomposites,were prepared.The tribological behavior of the steel...In the present work,two types of novel nano additives,titanium sulfonate ligand/black phosphorus(TiLi/BP)and titanium dioxide/black phosphorus(TiCVBP)nanocomposites,were prepared.The tribological behavior of the steel/steel friction pairs lubricated by polyalphaolefins type 6(PA06)containing the nanocomposites under boundary lubrication was studied.The worn surfaces were analyzed using modem surface techniques.The experimental results show that the rubbed surfaces became smooth and showed little wear with the addition of the nanocomposites.TiO_(2)/BP nanocomposites can significantly improve the lubricity of BP nanosheets under high contact stress.The synergistic roles of the load-bearing abilities and rolling effect of TiO_(2) nanoparticles,the slip induced by the BP with its layered structure,and the establishment of a tribofilm on the sliding interface are the basis of the tribological mechanisms.展开更多
Nanostructured anisotropic Nd-Fe-B/Fe(C) composite powders were prepared by coating Fe(C) softmagnetic nanoparticles on HDDR Nd-Fe-B hard magnetic powders using iron pentacarbonyl Fe(CO)5 as soft-phase precursor.The e...Nanostructured anisotropic Nd-Fe-B/Fe(C) composite powders were prepared by coating Fe(C) softmagnetic nanoparticles on HDDR Nd-Fe-B hard magnetic powders using iron pentacarbonyl Fe(CO)5 as soft-phase precursor.The effect of Fe(CO)5-loading amount on soft-phase purity,coating morphology and magnetic properties of the composite powders was investigated.Dense and continuous Fe(C) softphase coatings with average particle sizes of 58-68 nm are obtained at Fe(CO)5 loading amounts of x <12 wt%,leading to enhanced remanence and improved energy product of the coated powders.Positive value in δM-plots and single-phase-like demagnetization curves are observed in the Nd-Fe-B/Fe(C) composite powders,indicating the exchange coupling effect between the coated Fe(C) soft phases and the Nd-Fe-B hard phase.展开更多
文摘Pervaporation desalination by highly hydrophilic materials such as poly(vinyl alcohol)(PVA)based separation membrane is a burgeoning technology of late years.However,the improvement of membrane flux in pervaporation desalination has been a difficult task.Here,a novel hybrid membrane with doped graphene oxide quantum dots(GOQDs)which is rich in hydrophilic groups and small size into the matrix of PVA was prepared to improve the membrane flux.The membranes structures were described by field emission scanning electron microscopy(FESEM),atomic force microscopy(AFM),Fourier transform infrared(FT-IR),differential scanning calorimetry(DSC),thermogravimetric analysis(TGA)and X-ray diffraction(XRD).And more,Water contact angle,swelling degree,and pervaporation properties were carried out to explore the effect of GOQDs in PVA matrix.In addition,GOQDs content in the hybrid membrane,NaCl concentration,and feed temperature were investigated accordingly.Moreover,the hydrogen bonds between PVA chains were weakened by the interaction between GOQDs and PVA chains.Significantly,the hybrid membrane with optimized doped GOQDs content,200 mg·L^(-1),displays a high membrane flux of 17.09 kg·m^(-2)·h^(-1)and the salt rejection is consistently greater than 99.6%.
基金supported by the National Natural Science Foundation of China(No.51875155)。
文摘The tribological behavior of 316L stainless steel/CoCrMo alloy contacts under aqueous lubrication was investigated in this work.Three types of microgels including poly(N-isopropylacrylamide)(PNIPAM),polyacrylic acid(PAA),and poly(N-isopropylacrylamide-co-acrylic acid)(PNIPAM-co-PAA)were prepared and used as lubricant additives in aqueous solutions.Tribological tests were conducted using a ball-on-disk reciprocating tribometer,over a range of temperatures,pH,and concentrations of the microgels.The PNIPAM-co-PAA microgels were proven to have excellent anti-friction and anti-wear properties,depending on the temperature and pH values of the solutions.The maximum friction coefficient coincided with the lower critical solution temperature of the PNIPAM-co-PAA microgels at 32°C.At the same time,the friction coefficient increased with the increase in pH value of the lubricant solution with the PNIPAM-co-PAA microgels.The unique thermal-and pH-sensitive properties of the PNIPAM-co-PAA microgels provided a new strategy for controlling the friction and wear of steel/CoCrMo alloy contacts under aqueous lubrication.
基金Supported by the National Key Research and Development Program of China(2021YFC2600504)National Key Research and Development Program-Research on Bioterrorism Prevention and Control Technology in Important Public Places.
文摘Introduction:The swift advancement of biotechnology has presented both opportunities and challenges to our society,thrusting biosafety to the forefront of concern.Consequently,the evaluation of rescue capabilities in the event of a bioterrorism incident becomes of paramount importance.Currently,there is a notable absence of specific measurement criteria and a comprehensive evaluation system.This paper aims to establish a systematic approach towards assessing emergency response capabilities in the context of bioterrorism incidents.Methods:We employed an enhanced Delphi methodology to establish an index evaluation framework.Subsequently,the weight of the judgment matrix was ascertained via the application of the fuzzy comprehensive evaluation approach.This led to the creation of a fuzzy comprehensive evaluation model for bioterrorism rescue capability.Results:A modified Delphi study was conducted involving 11 experts across two rounds,achieving a response rate of 100%.The Kendall coordination coefficients recorded in the first and second rounds were 0.303 and 0.632,respectively(P<0.05).Upon comprehensive analysis involving score,coefficient of variation,and full score ratio,we distinguished five primary indicators and 25 secondary indicators.Subsequently,an evaluation model was developed based on the Analytic Hierarchy Process(AHP)tailored to assess the response to a rescue from bioterrorism.Discussion:The expert panel confirmed consensus on all aspects of the model,validating its comprehensive content.The succeeding course of action involves converting the assessment model to a measurable scale,affirming its functionality,and implementing it in practical evaluation tasks to further enhance the capabilities of the biological incident rescue team.
基金support of the National Natural Science Foundation of China(Grant No.51875155)the Fundamental Research Funds for the Central Universities(Grant No.PA2019GDQT0017).
文摘In the present work,two types of novel nano additives,titanium sulfonate ligand/black phosphorus(TiLi/BP)and titanium dioxide/black phosphorus(TiCVBP)nanocomposites,were prepared.The tribological behavior of the steel/steel friction pairs lubricated by polyalphaolefins type 6(PA06)containing the nanocomposites under boundary lubrication was studied.The worn surfaces were analyzed using modem surface techniques.The experimental results show that the rubbed surfaces became smooth and showed little wear with the addition of the nanocomposites.TiO_(2)/BP nanocomposites can significantly improve the lubricity of BP nanosheets under high contact stress.The synergistic roles of the load-bearing abilities and rolling effect of TiO_(2) nanoparticles,the slip induced by the BP with its layered structure,and the establishment of a tribofilm on the sliding interface are the basis of the tribological mechanisms.
基金Project supported by the National Natural Science Foundation of China(51771219,51771220,and 51422106)the State Key Laboratory of Rare Earth Permanent Magnetic Materials Opening Foundation(SKLREPM170F03)+1 种基金the China Postdoctoral Science Foundation(2016M601989)the Natural Science Foundation of Ningbo City(2016A610249 and 2017A610030)
文摘Nanostructured anisotropic Nd-Fe-B/Fe(C) composite powders were prepared by coating Fe(C) softmagnetic nanoparticles on HDDR Nd-Fe-B hard magnetic powders using iron pentacarbonyl Fe(CO)5 as soft-phase precursor.The effect of Fe(CO)5-loading amount on soft-phase purity,coating morphology and magnetic properties of the composite powders was investigated.Dense and continuous Fe(C) softphase coatings with average particle sizes of 58-68 nm are obtained at Fe(CO)5 loading amounts of x <12 wt%,leading to enhanced remanence and improved energy product of the coated powders.Positive value in δM-plots and single-phase-like demagnetization curves are observed in the Nd-Fe-B/Fe(C) composite powders,indicating the exchange coupling effect between the coated Fe(C) soft phases and the Nd-Fe-B hard phase.
