At present, with the rapid development of China's economy, the integration of urban and rural areas has been strengthened to ease the tension in the housing field, and the number of high-rise residential buildings...At present, with the rapid development of China's economy, the integration of urban and rural areas has been strengthened to ease the tension in the housing field, and the number of high-rise residential buildings and shopping malls has been increasing, which has brought great difficulties to the fire control work. In the process of design and construction, combined with the requirements of fire control management in the new era, attention should be paid to centralized control of smoke control devices and HVAC fire fighting equipment, so as to ensure the quality of HVAC fire fighting projects, reduce the possibility of fire and other accidents, and protect the safety of people's lives and property.展开更多
With the development of society, the development of China's subway industry construction has also improved. Subways have become a part of big cities, and vital public transport is essential in every region. It has...With the development of society, the development of China's subway industry construction has also improved. Subways have become a part of big cities, and vital public transport is essential in every region. It has many advantages, such as energy saving, major surgery, more and more popular, welcome, social recognition and widespread praise. In recent years, subway traffic accidents occur frequently, which causes people to attach great importance to subway fire safety management. Therefore, the characteristics and countermeasures of urban subway construction and fire safety community management are analyzed.展开更多
The paper described a newly developed high performance compressed air foam system(CAFS). The effective system generates uniform foam w ith greater momentum by injecting compressed air into flowing foam solution. Foa ...The paper described a newly developed high performance compressed air foam system(CAFS). The effective system generates uniform foam w ith greater momentum by injecting compressed air into flowing foam solution. Foa m generated by this system presented superior viscous and wetting properties to water.A pendulum system was designed to measure yield stress of foam. The results pro ved the existence of yield stress of foam. And the increasing tendency of yield stress with gas fraction and bubble size has also been found out.展开更多
Three novel fluorinated cationic surfactants were prepared by adopting perfluoro-2-methy1-2-pentene as raw substrate. The as-obtained fluorinated cationic surfactants exhibited excellent surface properties, all of the...Three novel fluorinated cationic surfactants were prepared by adopting perfluoro-2-methy1-2-pentene as raw substrate. The as-obtained fluorinated cationic surfactants exhibited excellent surface properties, all of them can reduce the surface tension of water to below 20.00mN/m at the critical micelle concentrations （CMC）. The incorporation of SDS, AOS, APG or LAB into 2-（4-（3,3,4,4,5,5,5-heptafluoro- 2,2-bis（trifluoromethyl）pentyl）benzamido）-N,N-dimethylethana-mine oxide 4a could generate much lower CMC and surface tension value at the CMC than individual 4a. Especially, the surface tension values of that combined APG/4a can be reduced to 17.31 mN/m. The excellent surface activities and their remarkable compatibility to various types of hydrocarbon surfactants make them as sustainable alternatives to PFOA （perfluorooctanoic acid, C7F15CO2H） and PFOS （perfluorooctane sulphonate, C8F17SO3X, with X = K, Na, H）.展开更多
Born in 1969 in New Orleans,Louisiana USA,Wesley Hill spent most of her early life in the Southern region of America including completing her BSc in Forest Management from the University of Arkansas in 1993.While stil...Born in 1969 in New Orleans,Louisiana USA,Wesley Hill spent most of her early life in the Southern region of America including completing her BSc in Forest Management from the University of Arkansas in 1993.While still completing her degree,she was hired as a co-op student for the United States Forest Service in Driggs,Idaho at the Teton Basin Ranger Station and began her work in backcountry Wilderness Management in the heart of the Teton mountain range in the states of Wyoming and Idaho,USA.Wesley managed the 143,000 acre Jedediah Smith Wilderness area bordering Grand Teton National Park which included backcountry monitoring of hikers and backpackers,avalanche search and rescue,fire fighting,trail building,supervising additional summer ranger staff,and ensuring all visitors were informed and abiding by the‘camping in bear country’camping and hiking regulations since many grizzly and black bears lived in the immediate area.展开更多
Research and development of novel fluorine‐free materials to replace fluorinated aqueous film‐forming foam(AFFF)are crucial for improving pool fire suppression performance and protecting the environment.In this stud...Research and development of novel fluorine‐free materials to replace fluorinated aqueous film‐forming foam(AFFF)are crucial for improving pool fire suppression performance and protecting the environment.In this study,we report the thermo‐responsive fluorine‐free foam stabilized by triblock PEO–PPO–PEO copolymers(EO)_(100)(PO)_(65)(EO)_(100)for pool fire suppression.Small‐angle X‐ray scattering(SAXS)and reflected light interferometric techniques are conducted to study the molecular self‐assembly in bulk and film thinning behavior,and the foaming kinetics of copolymer solution and thermophysical properties of the liquid foam are studied by dynamic surface tension and oscillatory rheology analysis.At room temperature,the amphipathic structure of PEO–PPO–PEO makes it possible to absorb at the air–liquid interface forming large‐scale liquid foams containing the mobile films with a detergent state.Upon heating to the surface cooling temperature of burning oil,the mobile films can be actively switched into mechanically strong films with rigid surfaces.The in situ switching of the two interfacial states leads to the significant enhancement of the foam stability,especially under the dual defoaming effects of heat and oil.What's more,it is observed that the confinement of organized copolymer micelles in the Plateau borders and micellar self‐layering in film confinement induce drainage delay of foam and film's stepwise thinning phenomenon,further increasing film thickness and enhancing the thermal stability of the foam.In standard fire‐fighting tests,it is proved that the burnback performance exhibited by thermo‐responsive copolymer foams is three times better than that for classical fluorine‐free foams and almost 1.5 times higher than that for commercial AFFF.展开更多
文摘At present, with the rapid development of China's economy, the integration of urban and rural areas has been strengthened to ease the tension in the housing field, and the number of high-rise residential buildings and shopping malls has been increasing, which has brought great difficulties to the fire control work. In the process of design and construction, combined with the requirements of fire control management in the new era, attention should be paid to centralized control of smoke control devices and HVAC fire fighting equipment, so as to ensure the quality of HVAC fire fighting projects, reduce the possibility of fire and other accidents, and protect the safety of people's lives and property.
文摘With the development of society, the development of China's subway industry construction has also improved. Subways have become a part of big cities, and vital public transport is essential in every region. It has many advantages, such as energy saving, major surgery, more and more popular, welcome, social recognition and widespread praise. In recent years, subway traffic accidents occur frequently, which causes people to attach great importance to subway fire safety management. Therefore, the characteristics and countermeasures of urban subway construction and fire safety community management are analyzed.
文摘The paper described a newly developed high performance compressed air foam system(CAFS). The effective system generates uniform foam w ith greater momentum by injecting compressed air into flowing foam solution. Foa m generated by this system presented superior viscous and wetting properties to water.A pendulum system was designed to measure yield stress of foam. The results pro ved the existence of yield stress of foam. And the increasing tendency of yield stress with gas fraction and bubble size has also been found out.
基金supported by the National Natural Science Foundation of China (No. 2167020782)the Science and Technology Commission of Shanghai Municipality (No. 15DZ2281500)
文摘Three novel fluorinated cationic surfactants were prepared by adopting perfluoro-2-methy1-2-pentene as raw substrate. The as-obtained fluorinated cationic surfactants exhibited excellent surface properties, all of them can reduce the surface tension of water to below 20.00mN/m at the critical micelle concentrations （CMC）. The incorporation of SDS, AOS, APG or LAB into 2-（4-（3,3,4,4,5,5,5-heptafluoro- 2,2-bis（trifluoromethyl）pentyl）benzamido）-N,N-dimethylethana-mine oxide 4a could generate much lower CMC and surface tension value at the CMC than individual 4a. Especially, the surface tension values of that combined APG/4a can be reduced to 17.31 mN/m. The excellent surface activities and their remarkable compatibility to various types of hydrocarbon surfactants make them as sustainable alternatives to PFOA （perfluorooctanoic acid, C7F15CO2H） and PFOS （perfluorooctane sulphonate, C8F17SO3X, with X = K, Na, H）.
文摘Born in 1969 in New Orleans,Louisiana USA,Wesley Hill spent most of her early life in the Southern region of America including completing her BSc in Forest Management from the University of Arkansas in 1993.While still completing her degree,she was hired as a co-op student for the United States Forest Service in Driggs,Idaho at the Teton Basin Ranger Station and began her work in backcountry Wilderness Management in the heart of the Teton mountain range in the states of Wyoming and Idaho,USA.Wesley managed the 143,000 acre Jedediah Smith Wilderness area bordering Grand Teton National Park which included backcountry monitoring of hikers and backpackers,avalanche search and rescue,fire fighting,trail building,supervising additional summer ranger staff,and ensuring all visitors were informed and abiding by the‘camping in bear country’camping and hiking regulations since many grizzly and black bears lived in the immediate area.
基金supported by the Basic Research Program of Jiangsu Province(No.BE2020663)the Opening Fund of the State Key Laboratory of Fire Science of the University of Science and Technology of China(No.HZ2022‐KF‐09).
文摘Research and development of novel fluorine‐free materials to replace fluorinated aqueous film‐forming foam(AFFF)are crucial for improving pool fire suppression performance and protecting the environment.In this study,we report the thermo‐responsive fluorine‐free foam stabilized by triblock PEO–PPO–PEO copolymers(EO)_(100)(PO)_(65)(EO)_(100)for pool fire suppression.Small‐angle X‐ray scattering(SAXS)and reflected light interferometric techniques are conducted to study the molecular self‐assembly in bulk and film thinning behavior,and the foaming kinetics of copolymer solution and thermophysical properties of the liquid foam are studied by dynamic surface tension and oscillatory rheology analysis.At room temperature,the amphipathic structure of PEO–PPO–PEO makes it possible to absorb at the air–liquid interface forming large‐scale liquid foams containing the mobile films with a detergent state.Upon heating to the surface cooling temperature of burning oil,the mobile films can be actively switched into mechanically strong films with rigid surfaces.The in situ switching of the two interfacial states leads to the significant enhancement of the foam stability,especially under the dual defoaming effects of heat and oil.What's more,it is observed that the confinement of organized copolymer micelles in the Plateau borders and micellar self‐layering in film confinement induce drainage delay of foam and film's stepwise thinning phenomenon,further increasing film thickness and enhancing the thermal stability of the foam.In standard fire‐fighting tests,it is proved that the burnback performance exhibited by thermo‐responsive copolymer foams is three times better than that for classical fluorine‐free foams and almost 1.5 times higher than that for commercial AFFF.
