A micro-layered structure was observed in the stable rust layer through dry–wet cycle corrosion tests.The microstructure,element distribution,and corrosion resistance mechanism of this layer structure in the marine i...A micro-layered structure was observed in the stable rust layer through dry–wet cycle corrosion tests.The microstructure,element distribution,and corrosion resistance mechanism of this layer structure in the marine industrial atmosphere were investigated by focused ion beam–scanning electron microscopy and high-resolution transmission electron microscopy.The inner rust layer of weathering steel(WS)exhibited layered enrichment of Cr,Cu,Ti,and other alloying elements.This layered structure comprised a fully amorphous region rich in Cr and Ti,as well as an amorphous and nanocrystalline region rich in Fe but poor in Cr.Only the completely amorphous region of the inner rust layer demonstrated a strong adsorption effect on Cl^(−).Cr-rich amorphous region played a pivotal role in reducing the corrosion of WS in the marine industrial atmospheric environment.The interface between the amorphous and nanocrystalline regions,as well as cracks within the interlayer,facilitated Cl^(−)transport,while the intact interlayer effectively hindered HSO_(3)^(−).展开更多
The plasma actuation (PA) effect on the snow falling flow was investigated using a plasma electrode with weather resistant design and the natural snow wind facility of the Hokkaido University of Science. NACA0015 test...The plasma actuation (PA) effect on the snow falling flow was investigated using a plasma electrode with weather resistant design and the natural snow wind facility of the Hokkaido University of Science. NACA0015 test blade with chord length c of 300 mm was used. Wind tunnel tests were carried out under the angle of the attack of the blade was fixed at 15 degrees, and the main flow velocity is U=5 m/s. PIV (Particle image velocimetry) measurements were conducted on various PA conditions using natural dry snowflakes as a tracer. When the actuator was driven under the condition of the fundamental frequency of F=50 kHz, and the pulsed modulated frequency f of fc/U=1 and Duty ratio (Ratio of plasma ON time to pulse duration time) =1%, movement of snowflakes was controlled the most effectively tested. It was clarified that the fundamental frequency of PA also affects the control of snow flow. Under snowfall conditions, the weather resistant designed plasma electrode has suffered no damage and operated successfully.展开更多
The ZnO-B203-SiO2 glass doped with Nd2O3 and Gd2O3 was prepared by high temperature melt cooling method. The standard sample of the zinc borosilicate glass was placed in the constant temperature and humidity chamber i...The ZnO-B203-SiO2 glass doped with Nd2O3 and Gd2O3 was prepared by high temperature melt cooling method. The standard sample of the zinc borosilicate glass was placed in the constant temperature and humidity chamber in order to simulate the atmospheric corrosion process. The surface of the weathered glass was analyzed by scanning electron microscope and energy disper- sive spectrometry and the filtrate was analyzed by inductively coupled plasma-atomic emission spectrometry. The results showed that humidity was the most important factor influencing weathering; the morphology of glass surface of altered layer and the product on the surface was observed; the corroding degree of the zinc borosilicate glass doped with Nd or Gd was significantly lighter than that of the base glass. Adding rare earth Nd or Gd in the zinc borosilicate glass could suppress Na, Zn, Si ion release in weathering.展开更多
Weathering steel is widely used in various fields due to its excellent mechanical properties and high corrosion resistance. The effect of chromium content on the S450 EW weathering steel in cyclic immersion test was s...Weathering steel is widely used in various fields due to its excellent mechanical properties and high corrosion resistance. The effect of chromium content on the S450 EW weathering steel in cyclic immersion test was studied. The results indicated that the corrosion resistance of S450 EW weathering steel is closely related to chromium content. The addition of chromium significantly inhibited the weathering steel corrosion. The corrosion rate of experimental steel after 96 h immersion was 1.101 g·m-2·h-1. The rust of S450 EW weathering steel was mainly constituted of Fe OOH and Fe3O4 phase, and the elevation of chromium content promoted the formation of α-Fe OOH. The fine precipitates of the two phases contributed to the formation of dense dust layer of test steel. Furthermore, the increase of chromium is beneficial for the cure of original defects and cracks of the rust layer via the enrichment of chromium. The corrosion potential and the resistance of corrosion process were thus increased, protecting the experimental steel from further corrosion. A S450 EW steel with corrosion resistance more than 1.5 times of Q450NQR1 steel was prepared.展开更多
This article focuses on study of a relation between physical-mineralogical properties of sandstone used in Ptolemaic temples in Upper Egypt and its resistance of deterioration factors affecting it. In the present stud...This article focuses on study of a relation between physical-mineralogical properties of sandstone used in Ptolemaic temples in Upper Egypt and its resistance of deterioration factors affecting it. In the present study, sandstone samples were collected from four sites;namely the temples of Dendera, Esna, Edfu and Kom Ombo which are located in Upper Egypt. Polarized light microscope (PLM), Scanning Electron Microscope (SEM), X-Ray diffraction (XRD) and energy-dispersive X-ray spectroscopy (EDX) were used to determine mineralogical properties, microstructure, and chemical compositions of the deteriorated sandstone samples, addition to physical properties tests;results of the study confirmed that sandstone samples containing a high percentage of salts, clay minerals and iron oxides have been significantly affected by deterioration factors. The deteriorated sandstone samples were treated by paraloid B72 3% enhanced with Nano silica 5% to improve the physical properties of stone. Results of the study indicated that the samples which were consolidated by Nanoparticles based on acrylic Copolymers (Paraloid B72 and its Nanocomposite with Nano silica) achieved the best results for improvement of its physical-mineralogical properties. This is the ultimate aim of the study for the purpose of conservation and sustainability of building materials of the temples.展开更多
Combining conventional waterborne epoxy coatings(WEP)with specific functionalities is essential to increase their service life.However,designing multifunctional protective coatings with tunable interfaces to improve t...Combining conventional waterborne epoxy coatings(WEP)with specific functionalities is essential to increase their service life.However,designing multifunctional protective coatings with tunable interfaces to improve their corrosion and weather resistance remains challenging.In this study,based on intermolecular forces between quaternized lignosulfonate(QLS)and tertbutyl titanate,we prepared QLS-TiO_(2)nanocomposite with structural regularity and strong chemical bonding by a simple one-pot method.It was further used for doped modified WEP to prepare a high-performance QLS-TiO_(2)/WEP coating.The results showed that QLS-TiO_(2)can effectively scavenge radicals,absorb and reflect strong ultraviolet rays,and exhibit high dispersibility and interfacial compatibility in the epoxy matrix.Consequently,QLS-TiO_(2)/WEP coating demonstrated excellent weathering resistance,with the polymer chain segments within the coatings remaining intact after 240 h of accelerated aging test.Furthermore,QLS-TiO_(2)exhibited chemical stability and impressive anti-corrosion properties.Its incorporation into epoxy coatings effectively prolonged the corrosion pathway.Therefore,QLS-TiO_(2)/WEP demonstrated excellent anti-corrosion performance in high salt,acid,and alkali.Especially under acidic conditions,its|Z|10 mHzwas5.810×10^(7)Ωcm^(2),which improved three orders of magnitude compared with WEP(3.688×10~4Ωcm^(2)).This study innovates the design concept of high-performance biomass functional waterborne epoxy anti-corrosion coating and is conducive to the high-value utilization of biomass.展开更多
The seemingly useless reeds are prepared as thermal insulation materials,which not only meet the requirements of environmental sustainability but also enhance the added value of reeds,creating new economic benefits.Th...The seemingly useless reeds are prepared as thermal insulation materials,which not only meet the requirements of environmental sustainability but also enhance the added value of reeds,creating new economic benefits.The hydrophobicity of raw biomass surfaces leads to problems such as weak bonding strength and non-dense structure in the formed materials,as well as issues related to the residual insect infestations on the surface.In this study,reed straw was used as the raw material,and foamed geopolymer was used as the binder to prepare building insulation materials based reed.To improve the interfacial adhesion performance between reed straw and foamed geopolymer,a thermochemical modification method-thermal carbonization,was proposed.In this study,the mechanical properties and hydraulic properties of the studied materials with different degrees of surface thermal modification were tested,especially the fire resistance performance,and weathering resistance performance rarely found in published literature.When the surface thermal modification condition of reed straw was 250℃(30 min),the comprehensive performance of reed-based building insulation materials was the best,when the studied material density was 321.3 kg/m^(3);the compressive strength was 0.59 MPa;the thermal conductivity was 0.101 W/(m·K);the pH was 11.27;the moisture absorption rate was 25.1%,and the compressive strength loss rate in wet-dry cycles was 18.5%.In addition,it had excellent fire resistance performance and weathering resistance performance.This new material can be widely used to improve the thermal insulation of traditional buildings and as sandwich filler in prefabricated buildings,such as preparing insulating walls.展开更多
基金supported by the High-quality Scientific Research Cultivation Project of Bengbu University(Grant No.2021pyxm03)the Natural Science Foundation of the Higher Education Institutions of Anhui Province(Grant No.KJ2021A1118)+1 种基金the Provincial Quality Engineering Project of Anhui Universities(Grant No.2022zygzts066)the Discipline(Major)Leadership Development Program of Anhui Province(DTR2023057).
文摘A micro-layered structure was observed in the stable rust layer through dry–wet cycle corrosion tests.The microstructure,element distribution,and corrosion resistance mechanism of this layer structure in the marine industrial atmosphere were investigated by focused ion beam–scanning electron microscopy and high-resolution transmission electron microscopy.The inner rust layer of weathering steel(WS)exhibited layered enrichment of Cr,Cu,Ti,and other alloying elements.This layered structure comprised a fully amorphous region rich in Cr and Ti,as well as an amorphous and nanocrystalline region rich in Fe but poor in Cr.Only the completely amorphous region of the inner rust layer demonstrated a strong adsorption effect on Cl^(−).Cr-rich amorphous region played a pivotal role in reducing the corrosion of WS in the marine industrial atmospheric environment.The interface between the amorphous and nanocrystalline regions,as well as cracks within the interlayer,facilitated Cl^(−)transport,while the intact interlayer effectively hindered HSO_(3)^(−).
基金The present research was carried out as a part of the Fukushima prefecture renewable energy-related technology demonstration research support project.The wind tunnel test was supported by the devoted cooperation of Mr.Shibata,S.,Mr.Takahashi,T.,Mr.Tanaka,T.,Mr.Iyobe,K.and Mr.Sugawara,T.,who are students of the Department of Mechanical Engineering of the Hokkaido University of Science.We would like to express our gratitude.
文摘The plasma actuation (PA) effect on the snow falling flow was investigated using a plasma electrode with weather resistant design and the natural snow wind facility of the Hokkaido University of Science. NACA0015 test blade with chord length c of 300 mm was used. Wind tunnel tests were carried out under the angle of the attack of the blade was fixed at 15 degrees, and the main flow velocity is U=5 m/s. PIV (Particle image velocimetry) measurements were conducted on various PA conditions using natural dry snowflakes as a tracer. When the actuator was driven under the condition of the fundamental frequency of F=50 kHz, and the pulsed modulated frequency f of fc/U=1 and Duty ratio (Ratio of plasma ON time to pulse duration time) =1%, movement of snowflakes was controlled the most effectively tested. It was clarified that the fundamental frequency of PA also affects the control of snow flow. Under snowfall conditions, the weather resistant designed plasma electrode has suffered no damage and operated successfully.
基金Project supported by National Natural Science Foundation of China(51025416,51202104,51362019)Natural Science Foundation of the Inner Mongolia Autonomous Region(2012MS0807)Program for Young Talents of Inner Mongolia Autonomous Region
文摘The ZnO-B203-SiO2 glass doped with Nd2O3 and Gd2O3 was prepared by high temperature melt cooling method. The standard sample of the zinc borosilicate glass was placed in the constant temperature and humidity chamber in order to simulate the atmospheric corrosion process. The surface of the weathered glass was analyzed by scanning electron microscope and energy disper- sive spectrometry and the filtrate was analyzed by inductively coupled plasma-atomic emission spectrometry. The results showed that humidity was the most important factor influencing weathering; the morphology of glass surface of altered layer and the product on the surface was observed; the corroding degree of the zinc borosilicate glass doped with Nd or Gd was significantly lighter than that of the base glass. Adding rare earth Nd or Gd in the zinc borosilicate glass could suppress Na, Zn, Si ion release in weathering.
基金Item Sponsored by National Natural Science Foundation of China(51104039)Fundamental Research Funds for the National Key Basic Research Program of China(2012CB626812)
文摘Weathering steel is widely used in various fields due to its excellent mechanical properties and high corrosion resistance. The effect of chromium content on the S450 EW weathering steel in cyclic immersion test was studied. The results indicated that the corrosion resistance of S450 EW weathering steel is closely related to chromium content. The addition of chromium significantly inhibited the weathering steel corrosion. The corrosion rate of experimental steel after 96 h immersion was 1.101 g·m-2·h-1. The rust of S450 EW weathering steel was mainly constituted of Fe OOH and Fe3O4 phase, and the elevation of chromium content promoted the formation of α-Fe OOH. The fine precipitates of the two phases contributed to the formation of dense dust layer of test steel. Furthermore, the increase of chromium is beneficial for the cure of original defects and cracks of the rust layer via the enrichment of chromium. The corrosion potential and the resistance of corrosion process were thus increased, protecting the experimental steel from further corrosion. A S450 EW steel with corrosion resistance more than 1.5 times of Q450NQR1 steel was prepared.
文摘This article focuses on study of a relation between physical-mineralogical properties of sandstone used in Ptolemaic temples in Upper Egypt and its resistance of deterioration factors affecting it. In the present study, sandstone samples were collected from four sites;namely the temples of Dendera, Esna, Edfu and Kom Ombo which are located in Upper Egypt. Polarized light microscope (PLM), Scanning Electron Microscope (SEM), X-Ray diffraction (XRD) and energy-dispersive X-ray spectroscopy (EDX) were used to determine mineralogical properties, microstructure, and chemical compositions of the deteriorated sandstone samples, addition to physical properties tests;results of the study confirmed that sandstone samples containing a high percentage of salts, clay minerals and iron oxides have been significantly affected by deterioration factors. The deteriorated sandstone samples were treated by paraloid B72 3% enhanced with Nano silica 5% to improve the physical properties of stone. Results of the study indicated that the samples which were consolidated by Nanoparticles based on acrylic Copolymers (Paraloid B72 and its Nanocomposite with Nano silica) achieved the best results for improvement of its physical-mineralogical properties. This is the ultimate aim of the study for the purpose of conservation and sustainability of building materials of the temples.
基金financially supported by the National Natural Science Foundation of China(No.22278092)the Young Talent Support Project of Guangzhou Association for Science and Technology(No.QT2024-004)+2 种基金the Science and Technology Research Project of Guangzhou(Nos.2023A03J0034,2023A04J0077,202102020467 and 2023A03J0064)the Key Discipline of Materials Science and Engineering,Bureau of Education of Guangzhou(No.202255464)the National College Student Innovation Training Program of Guangzhou University(No.202411078020)
文摘Combining conventional waterborne epoxy coatings(WEP)with specific functionalities is essential to increase their service life.However,designing multifunctional protective coatings with tunable interfaces to improve their corrosion and weather resistance remains challenging.In this study,based on intermolecular forces between quaternized lignosulfonate(QLS)and tertbutyl titanate,we prepared QLS-TiO_(2)nanocomposite with structural regularity and strong chemical bonding by a simple one-pot method.It was further used for doped modified WEP to prepare a high-performance QLS-TiO_(2)/WEP coating.The results showed that QLS-TiO_(2)can effectively scavenge radicals,absorb and reflect strong ultraviolet rays,and exhibit high dispersibility and interfacial compatibility in the epoxy matrix.Consequently,QLS-TiO_(2)/WEP coating demonstrated excellent weathering resistance,with the polymer chain segments within the coatings remaining intact after 240 h of accelerated aging test.Furthermore,QLS-TiO_(2)exhibited chemical stability and impressive anti-corrosion properties.Its incorporation into epoxy coatings effectively prolonged the corrosion pathway.Therefore,QLS-TiO_(2)/WEP demonstrated excellent anti-corrosion performance in high salt,acid,and alkali.Especially under acidic conditions,its|Z|10 mHzwas5.810×10^(7)Ωcm^(2),which improved three orders of magnitude compared with WEP(3.688×10~4Ωcm^(2)).This study innovates the design concept of high-performance biomass functional waterborne epoxy anti-corrosion coating and is conducive to the high-value utilization of biomass.
基金supported by the National Natural Science Foundation of China(No.52076070,No.52008166)the Natural Science Foundation of Hunan Province(No.2021JJ30256,No.2022JJ30139)。
文摘The seemingly useless reeds are prepared as thermal insulation materials,which not only meet the requirements of environmental sustainability but also enhance the added value of reeds,creating new economic benefits.The hydrophobicity of raw biomass surfaces leads to problems such as weak bonding strength and non-dense structure in the formed materials,as well as issues related to the residual insect infestations on the surface.In this study,reed straw was used as the raw material,and foamed geopolymer was used as the binder to prepare building insulation materials based reed.To improve the interfacial adhesion performance between reed straw and foamed geopolymer,a thermochemical modification method-thermal carbonization,was proposed.In this study,the mechanical properties and hydraulic properties of the studied materials with different degrees of surface thermal modification were tested,especially the fire resistance performance,and weathering resistance performance rarely found in published literature.When the surface thermal modification condition of reed straw was 250℃(30 min),the comprehensive performance of reed-based building insulation materials was the best,when the studied material density was 321.3 kg/m^(3);the compressive strength was 0.59 MPa;the thermal conductivity was 0.101 W/(m·K);the pH was 11.27;the moisture absorption rate was 25.1%,and the compressive strength loss rate in wet-dry cycles was 18.5%.In addition,it had excellent fire resistance performance and weathering resistance performance.This new material can be widely used to improve the thermal insulation of traditional buildings and as sandwich filler in prefabricated buildings,such as preparing insulating walls.
