The dispersion state of nano-TiO2 particles was studied by using transmission electron microscopy (TEM)and Fourier transform infrared spectroscopy (FT-IR). Nanoparticles can be fully dispersed by specific hyperdis...The dispersion state of nano-TiO2 particles was studied by using transmission electron microscopy (TEM)and Fourier transform infrared spectroscopy (FT-IR). Nanoparticles can be fully dispersed by specific hyperdispersant. The improvement of nano-TiO2 in thermal behavior and flame retardation of acrylic polymer and fire-resistant coating was investigated by differential thermal analysis (DTA), thermogravimetry (TG)and fire-resistant time test. It is demonstrated that nano-TiO2 is helpful for enhancing the thermal stability,anti-oxidation and fire-resistant properties of acrylic polymer and fire-resistant coating.展开更多
Paper was one of the greatest inventions in ancient China,and it greatly promoted the rapid development of human civilization.Even in today's electronic information age,paper and paper-derived products are still i...Paper was one of the greatest inventions in ancient China,and it greatly promoted the rapid development of human civilization.Even in today's electronic information age,paper and paper-derived products are still indispensable to people's daily work and life.However;the traditional paper based on cellulose fibers from plants has some problems.For instance:(1)papermaking consumes a large amount of precious natural resources such as trees;(2)the papermaking industry causes environmental pollution;(3)the traditional paper consisting of organic cellulose fibers is highly flammable and easy to burn;(4)the traditional paper based on cellulose fibers turns to yellow color with time;(5)the lifetime of the traditional paper is relatively short because of the degradation of cellulose fibers.More efforts are needed to investigate and solve these problems facing the traditional paper.In recent years,a new kind of multifunctional fire-resistant paper based on ultralong hydroxyapatite nanowires has been developed and investigated for various applications,and many research findings have been documented in the literature.This review article provides a comprehensive summary and discussion on recent research advances for this new kind of multifunctional fire-resistant paper based on ultralong hydroxyapatite nanowires,including the synthesis,properties,applications,and future perspectives.展开更多
Trials to develop a C-Mn-Mo-Nb type fire-resistant steel have been carried out by adopting recrystallization rolling (RCR) + air cooling (AC),two-stage rolling (TSR) + AC and RCR + water cooling (WC).Both RCR and TSR ...Trials to develop a C-Mn-Mo-Nb type fire-resistant steel have been carried out by adopting recrystallization rolling (RCR) + air cooling (AC),two-stage rolling (TSR) + AC and RCR + water cooling (WC).Both RCR and TSR followed by AC resulted in polygonal ferrite (F) + pearlite (P) microstructure,while F + bainite (B) microstructure was formed by RCR + WC.The plates with F+P microstructure show tensile strengths ≥490MPa,while those with F+B exhibit tensile strengths ≥590MPa.All the plates show favorable low yield ratios ≤ 0.75,good charpy v-notch impact property 】101J at 0℃ and satisfactory high temperature strength (≥2/3 of room temperature yield strength retained at 600℃).展开更多
In order to ensure fire-resistant property of the steel under the condition of the least molybdenum content,effects of molybdenum on microstructure and properties of the fire-resistant construction steel,specially on ...In order to ensure fire-resistant property of the steel under the condition of the least molybdenum content,effects of molybdenum on microstructure and properties of the fire-resistant construction steel,specially on high temperature strength were investigated.The results show that the room temperature and high temperature strength of the steel is enhanced due to increased Mo content but the impact toughness deteriorates at the same time.The fraction of bainite in the microstructure increases with increasing Mo content while the fractions of polygonal ferrite and pearlite decrease.Comparing with the steel of adding Nb alone,it was obvious that combined addition of Mo and Nb could provide better effect in high temperature strengthening.Addition of 0.25mass% Mo in the steel containing Nb could meet fire-resistant requirements of the construction steel and provide better economical effectiveness.展开更多
Superior thermal insulating and fire-retardant ceramic membranes are urgently demanded in the aerospace,construction,and chemical engineering industries.However,the generic characteristics of ceramic membranes,such as...Superior thermal insulating and fire-retardant ceramic membranes are urgently demanded in the aerospace,construction,and chemical engineering industries.However,the generic characteristics of ceramic membranes,such as brittleness,structural collapse,and crystallization-induced pulverization behavior,present a great plague to their practical applications.Herein,we report a highly flexible,mechanically stable,fire-retardant,and high-temperature-resistant ceramic membrane based on the interlocked Si_(3)N_(4) nanowires formed by the precursor pyrolysis method.The Si_(3)N_(4) nanowire membrane(SNM)has excellent high-temperature resistance under alcohol lamps and butane spray lance.The thermal insulation with a thermal conductivity as low as 0.056 W m^(-1)K^(-1)can be attributed to the high porosity of SNM,which makes it a desirable candidate for heat insulators under harsh conditions.More importantly,SNM exhibits thermal stability and robust mechanical properties in the range of 25 to 1300℃.The high-temperature resistance of SNM up to 1300℃is achieved by the four stages:Si3 N4 nanowires,Si_(3)N_(4)@SiO_(2) nanowires,SiO_(2) nanowires,and bead-like SiO_(2) nanowires.After heat-treated at 1300℃,the macroscopic size of SNM does not change significantly,and the interlocked structure is still maintained.Furthermore,SNM still maintains excellent mechanical properties,with tensile strength as high as 0.26 MPa.This work provides a facile method for fabricating excellent thermal insulating and fire-retardant ceramic membranes,showing prospective application prospects in the era of thermal insulating materials.展开更多
The nano-concentrates and flame retardant nano-coating were prepared in thhis study. The effect of nano-SiO2 on the corrosion resistance and fire resistance of ammonium polyphosphate-pentaerythritol-melamine (APP- PE...The nano-concentrates and flame retardant nano-coating were prepared in thhis study. The effect of nano-SiO2 on the corrosion resistance and fire resistance of ammonium polyphosphate-pentaerythritol-melamine (APP- PER-MEL) coating was investigated by differential thermal analysis (DTA), scanning electron microscopy (SEM), effective thermal conductivity (λ/d), X-ray photoelectron spectroscopy (XPS) and fire protection test. The chemical action and endothermic effect of ammonium polyphosphate, pentaerythritol and melamine in traditional flame retardant coating were damaged by salt spray condition, whereas the flame-retardant additives in the nano-coating demonstrated the good chemical interaction in salt spray condition. The uniformly dispersed nano-SiO2 particles could improve corrosion resistance of the coating, and hence nano-coating could remain the good fire-resistant properties even after 500 h salt spray test.展开更多
Fire disaster is the primary one of the facts of deforestation. Although in recent years the level of forest management and technique for fire suppression have been improving and fire fighting force has been strengthe...Fire disaster is the primary one of the facts of deforestation. Although in recent years the level of forest management and technique for fire suppression have been improving and fire fighting force has been strengthened, the area of fire has not been decreased obviously. Using biological fire resistant technique can effectively prevent the campaign fire. In this paper, fire resistant ability and component about 12 tree species, in mountain area of Daguishan, Guangxi Zhuang Autonomous Region, have been ...展开更多
文摘The dispersion state of nano-TiO2 particles was studied by using transmission electron microscopy (TEM)and Fourier transform infrared spectroscopy (FT-IR). Nanoparticles can be fully dispersed by specific hyperdispersant. The improvement of nano-TiO2 in thermal behavior and flame retardation of acrylic polymer and fire-resistant coating was investigated by differential thermal analysis (DTA), thermogravimetry (TG)and fire-resistant time test. It is demonstrated that nano-TiO2 is helpful for enhancing the thermal stability,anti-oxidation and fire-resistant properties of acrylic polymer and fire-resistant coating.
基金The financial support from the National Natural Science Foundation of China(21875277)is gratefully acknowledged.
文摘Paper was one of the greatest inventions in ancient China,and it greatly promoted the rapid development of human civilization.Even in today's electronic information age,paper and paper-derived products are still indispensable to people's daily work and life.However;the traditional paper based on cellulose fibers from plants has some problems.For instance:(1)papermaking consumes a large amount of precious natural resources such as trees;(2)the papermaking industry causes environmental pollution;(3)the traditional paper consisting of organic cellulose fibers is highly flammable and easy to burn;(4)the traditional paper based on cellulose fibers turns to yellow color with time;(5)the lifetime of the traditional paper is relatively short because of the degradation of cellulose fibers.More efforts are needed to investigate and solve these problems facing the traditional paper.In recent years,a new kind of multifunctional fire-resistant paper based on ultralong hydroxyapatite nanowires has been developed and investigated for various applications,and many research findings have been documented in the literature.This review article provides a comprehensive summary and discussion on recent research advances for this new kind of multifunctional fire-resistant paper based on ultralong hydroxyapatite nanowires,including the synthesis,properties,applications,and future perspectives.
文摘Trials to develop a C-Mn-Mo-Nb type fire-resistant steel have been carried out by adopting recrystallization rolling (RCR) + air cooling (AC),two-stage rolling (TSR) + AC and RCR + water cooling (WC).Both RCR and TSR followed by AC resulted in polygonal ferrite (F) + pearlite (P) microstructure,while F + bainite (B) microstructure was formed by RCR + WC.The plates with F+P microstructure show tensile strengths ≥490MPa,while those with F+B exhibit tensile strengths ≥590MPa.All the plates show favorable low yield ratios ≤ 0.75,good charpy v-notch impact property 】101J at 0℃ and satisfactory high temperature strength (≥2/3 of room temperature yield strength retained at 600℃).
文摘In order to ensure fire-resistant property of the steel under the condition of the least molybdenum content,effects of molybdenum on microstructure and properties of the fire-resistant construction steel,specially on high temperature strength were investigated.The results show that the room temperature and high temperature strength of the steel is enhanced due to increased Mo content but the impact toughness deteriorates at the same time.The fraction of bainite in the microstructure increases with increasing Mo content while the fractions of polygonal ferrite and pearlite decrease.Comparing with the steel of adding Nb alone,it was obvious that combined addition of Mo and Nb could provide better effect in high temperature strengthening.Addition of 0.25mass% Mo in the steel containing Nb could meet fire-resistant requirements of the construction steel and provide better economical effectiveness.
基金financially supported by the National Natural Science Foundation of China(Grant No.51872232)the Research Fund of the State Key Laboratory of Solidification Processing(NWPU),China(Grant No.136-QP-2015)+3 种基金the Key Scientific and Technological Innovation Research Team of Shaanxi Province(No.2022TD-31)the Key R&D Program of Shaanxi Province(No.2021ZDLGY14-04)the National Training Program of Innovation and Entrepreneurship for Undergraduates(Grand No.XN2022023)the Joint Funds of the National Natural Science Foundation of China(Grant No.U21B2067).
文摘Superior thermal insulating and fire-retardant ceramic membranes are urgently demanded in the aerospace,construction,and chemical engineering industries.However,the generic characteristics of ceramic membranes,such as brittleness,structural collapse,and crystallization-induced pulverization behavior,present a great plague to their practical applications.Herein,we report a highly flexible,mechanically stable,fire-retardant,and high-temperature-resistant ceramic membrane based on the interlocked Si_(3)N_(4) nanowires formed by the precursor pyrolysis method.The Si_(3)N_(4) nanowire membrane(SNM)has excellent high-temperature resistance under alcohol lamps and butane spray lance.The thermal insulation with a thermal conductivity as low as 0.056 W m^(-1)K^(-1)can be attributed to the high porosity of SNM,which makes it a desirable candidate for heat insulators under harsh conditions.More importantly,SNM exhibits thermal stability and robust mechanical properties in the range of 25 to 1300℃.The high-temperature resistance of SNM up to 1300℃is achieved by the four stages:Si3 N4 nanowires,Si_(3)N_(4)@SiO_(2) nanowires,SiO_(2) nanowires,and bead-like SiO_(2) nanowires.After heat-treated at 1300℃,the macroscopic size of SNM does not change significantly,and the interlocked structure is still maintained.Furthermore,SNM still maintains excellent mechanical properties,with tensile strength as high as 0.26 MPa.This work provides a facile method for fabricating excellent thermal insulating and fire-retardant ceramic membranes,showing prospective application prospects in the era of thermal insulating materials.
文摘The nano-concentrates and flame retardant nano-coating were prepared in thhis study. The effect of nano-SiO2 on the corrosion resistance and fire resistance of ammonium polyphosphate-pentaerythritol-melamine (APP- PER-MEL) coating was investigated by differential thermal analysis (DTA), scanning electron microscopy (SEM), effective thermal conductivity (λ/d), X-ray photoelectron spectroscopy (XPS) and fire protection test. The chemical action and endothermic effect of ammonium polyphosphate, pentaerythritol and melamine in traditional flame retardant coating were damaged by salt spray condition, whereas the flame-retardant additives in the nano-coating demonstrated the good chemical interaction in salt spray condition. The uniformly dispersed nano-SiO2 particles could improve corrosion resistance of the coating, and hence nano-coating could remain the good fire-resistant properties even after 500 h salt spray test.
基金the major project of forestry(No.2000-14)the National Natural Science of Beijing(No.6992025)
文摘Fire disaster is the primary one of the facts of deforestation. Although in recent years the level of forest management and technique for fire suppression have been improving and fire fighting force has been strengthened, the area of fire has not been decreased obviously. Using biological fire resistant technique can effectively prevent the campaign fire. In this paper, fire resistant ability and component about 12 tree species, in mountain area of Daguishan, Guangxi Zhuang Autonomous Region, have been ...