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Improving the catalytic performance of TiO_(2) by its surface deposition on CNT buckypapers for use in the removal of wastewater pollutants
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作者 Mariafrancesca Baratta Aleksey Vladimirovich Nezhdanov +6 位作者 Aleksey Valentinovich Ershov Donatella Aiello Anna Napoli Leonardo Di Donna Alexandr Ivanovic Mashin Fiore Pasquale Nicoletta Giovanni De Filpo 《新型炭材料(中英文)》 北大核心 2025年第2期456-481,共26页
Buckypapers(BPs)consist of carbon nanotube(CNT)membranes with good mechanical,thermal and elec-trical properties.We report the modification of CNT buckypapers by the surface deposition of a thin layer of ti-tanium dio... Buckypapers(BPs)consist of carbon nanotube(CNT)membranes with good mechanical,thermal and elec-trical properties.We report the modification of CNT buckypapers by the surface deposition of a thin layer of ti-tanium dioxide and their subsequent photocatalytic use for the removal of three wastewater pollutants:diclofenac(DF),carbofuran(CB)and methylene blue(MB).The results show the following decreases(RE)in the initial concentrations of these pollutants,REDF=99.5%,REMB=96%and RECB=90%after 90 min of exposure to UV-Vis radiation using~0.6 mg of photocatalyst.Experiments also showed that the degradation rate of diclofenac(k=0.1028 min^(−1))is respectively 3.5 and 6 times faster than the values for CB(k=0.0298 min^(−1))and MB(k=0.0174 min^(−1)),probably due to the easier bond cleavage in DF.UV-Vis irradiated solutions of these pollutants were then analyzed by mass spectrometry to identify the species formed during photocatalysis and suggest possible degradation paths for MB,DF,and CB.Data showed that the degradation of DF involves the formation of a photocyclization product through loss of HCl molecule,clearly consuming less energy than that needed for the opening of the central aromatic ring in MB,or the loss of the N-methyl amide functional group for CB. 展开更多
关键词 Carbon nanotubes Buckypapers NANOMATERIALS water pollutants Titanium dioxide
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N-doped activated carbons from leather waste produced by microwave activation for use as the cathode of Li-S batteries
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作者 Carolina Pano-Azucena Roberto Rosas-Rangel +5 位作者 Miguel Olvera-Sosa David Salvador González-González Rene Rangel-Mendez Luis Felipe Chazaro-Ruiz Miguel Avalos-Borja Javier Antonio Arcibar-Orozco 《新型炭材料(中英文)》 北大核心 2025年第2期392-408,共17页
The use of carbon from waste biomass has the potential to eliminate the drawbacks of Li-S batteries and improve their overall performance.Chrome-tanned-leather-shavings(CTLS)are a readily available waste product that ... The use of carbon from waste biomass has the potential to eliminate the drawbacks of Li-S batteries and improve their overall performance.Chrome-tanned-leather-shavings(CTLS)are a readily available waste product that can be transformed into porous carbon.We prepared an ac-tivated carbon by microwave pyrolysis combined with KOH activator using the CTLS as starting materials.The carbon had a specific surface area of 556 m^(2)g^(-1) and a honeycomb-like structure.Two kinds of N-doped activated carbons were then synthesized by thermal decomposition of the activated carbon,either combined with urea,or impregnated with eth-anolamine.Both N-doped activated carbons have an in-creased number of nitrogen and amine surface groups.However,only the urea treatment was effective in improv-ing the initial capacity of the cell(1363 mAh g^(-1)),which is probably linked to the sorption of long-chain polysulfides.This investigation confirms that it is possible to use the thermal de-composition of urea to obtain carbon materials from CTLS for use as the sulfur-host cathode in Li-S batteries and improve their performance.A radial basis function neural network was fitted to provide statistical support for the experimental results,which confirmed the importance of the nitrogen content of the carbons in determining the discharge capacity of the cells. 展开更多
关键词 Leather wastes Microwave activation Lithium-sulfur battery Urea decomposition Carbon material
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Review of wastewater treatment technologies,soil and water conservation measures in nuclear power plants,and inspirations to Fukushima accident
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作者 WANG Chu NIU Jianzhi +2 位作者 LUN Xiaoxiu ZHANG Linus BERNDTSSON Ronny 《中国水土保持科学》 CSCD 北大核心 2024年第6期10-28,193-200,共27页
[Background]The previous studies suggest that radioactive elements like Cs and Sr may adversely affect marine ecosystems and the fishing industry.Traditional treatment systems for radioactive wastewater like the Advan... [Background]The previous studies suggest that radioactive elements like Cs and Sr may adversely affect marine ecosystems and the fishing industry.Traditional treatment systems for radioactive wastewater like the Advanced Liquid Processing System(ALPS)and Kurion have faced challenges in limiting concentration and achieving safety criteria.Studies suggest potential long-term impacts on benthic organisms and seafood networks due to radioactive elements like Cs and Sr from the discharged radioactive wastewater,which may hinder post-disaster recovery and provoke economic losses in the fishing industry both domestically and internationally.A series of studies indicate that there are issues of Cs and Sr pollution migration in soil and water conservation in Fukushima.[Methods]To provide feasible solutions,the main article includes five nuclear wastewater treatment technologies,and soil and water conservation measures for different media(water and soil)were evaluated through reviewing the previous fifteen years'articles.To provide feasible solutions,the main articles,the phytoextraction technologies in Cs and Sr treatment within different land use areas were wildly analyzed(Camellia japonica,Arabidopsis halleri and other local species).[Results]1)A 99.9%removal rate for Cs^(+)and 99.5%for Sr^(2+)was achieved by the KFe[Fe(CN)_(6)]and BaSO_(4)co-precipitation method.2)For membrane filtration,Sr^(2+)and Cs^(+)were removed using metal-organic framework(MOF/graphene oxide)and ion exchange techniques using inorganic materials like titanosilicates.The absorption efficiency of membrane filtration for Sr^(2+)and Cs^(+)was at least 92%and 94%,respectively.The study analyzed soil and water conservation technologies in different land uses,river basins and catchments.3)The underground water treatment mainly were completed via the membrance technologies like reverse osmosis and Permeable Reactive Barriers(PRB)technologies.The ^(90) Sr concentration decreased 77%-91%compared to the initial concentration by PRB technology.These diverse methods offered effective strategies for radioactive wastewater treatment,especially the co-precipitation method may be feasible remediation measures to ensure ecological safety surrounding nuclear power utilizing areas.Soil and water conservation measures for soil pollution treatment mainly focused on the use of stabilizers to hinder the migration of Cs and Sr in the soil and the effects of wind erosion such as interpolyelectrolyte complexes.[Conclusions]We evaluated the pollution of Cs and Sr in the Fukushima nuclear radiation soil and water to provide solutions for the treatment of nuclear wastewater and to prevent radionuclide pollutants from migrating into the soil and water. 展开更多
关键词 Fukushima nuclear power accident nuclear wastewater treatment environmental strategy soil and water conservation technologies
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Utilization of Solid Waste Materials as Roadbed Fillers in Road Construction:a Review
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作者 AN Liang CHEN Wenwu +2 位作者 ZHAO Tianyu LI Lunji WANG Yingchun 《材料导报》 EI CAS CSCD 北大核心 2024年第S02期247-253,共7页
China has a large solid waste stockpile and a low resource utilisation rate,and the utilisation of solid waste resources is of great significance in promoting sustainable social development.In order to further promote... China has a large solid waste stockpile and a low resource utilisation rate,and the utilisation of solid waste resources is of great significance in promoting sustainable social development.In order to further promote the green and efficient development of China's road field,an overview of the current status of the application,research progress,hot frontiers,problems and their countermeasures based on the three aspects of industrial solid wastes,engineering solid wastes and municipal solid wastes in highway engineering was conducted,and the development prospect of the resourceful utilisation of solid waste in highway engineering was outlooked,with a view to promoting the development of China's green roads.Statistics on the stockpile,utilisation and comprehensive utilisation rate of industrial solid wastes in China are presented,and the optimal mixing amount,production process and application technology of industrial solid wastes for road base materials are systematically summarised.Based on the concept of high-value utilisation of solid waste,the mechanical properties,durability,construction technology and quality control standards of engineering solid waste applied in roadbed engineering are summarised,and the difficulties in the application of engineering solid waste in road engineering are summarised.Finally,the feasibility,mechanical properties and environmental characteristics of municipal solid waste domestic waste incinerator slag,waste tyres and plastics applied in road engineering are summarised.This review can provide references and lessons for the design and development of green roads,and promote the innovation and development of greening road engineering. 展开更多
关键词 industrial solid waste engineering solid waste municipal solid waste green road
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Mechanism of high concentration phosphorus wastewater treated by municipal solid waste incineration fly ash 被引量:4
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作者 钟山 高慧 +1 位作者 邝薇 刘元元 《Journal of Central South University》 SCIE EI CAS 2014年第5期1982-1988,共7页
The mechanism of removing phosphate by MSWI(municipal solid waste incineration)fly ash was investigated by SEM(scanning electron microscopy)with EDS(energy dispersion spectrum),XRD(X-ray diffraction),FT-IR(Fourier tra... The mechanism of removing phosphate by MSWI(municipal solid waste incineration)fly ash was investigated by SEM(scanning electron microscopy)with EDS(energy dispersion spectrum),XRD(X-ray diffraction),FT-IR(Fourier transform infrared spectroscopy),BET(specific surface area),and BJH(pore size distribution).The results indicate that the removal rate of phosphate(100 mg/L)in 50 mL phosphorus wastewater reaches at 99.9% as the dosage of MSWI fly ash being 0.9000 g under room temperature.The specific surface area of MSWI fly ash is less than 6.1 m2/g and the total pore volume is below 0.021 cm3/g,suggesting that the absorption capacity of calcite is too weak to play an important role in phosphate removal.SEM images show that drastic changes had taken place on its specific surface shape after reaction,and EDS tests indicate that some phosphate precipitates are formed and attached onto MSWI fly ash particles.Chemical precipitation is the main manner of phosphate removal and the main reaction is: 3Ca2++2 PO4 3-+xH2O→Ca3(PO4)2↓·xH2O.Besides,XRD tests show that the composition of MSWI fly ash is complex,but CaSO4 is likely to be the main source of Ca2+.The soluble heavy metals in MSWI fly ash are stabilized by phosphate. 展开更多
关键词 MSWI (municipal solid waste incineration) fly ash phosphorus wastewater PHOSPHATE MECHANISM heavy metal
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Overview coking plant & Lurgi gasifier plant waste water treatment
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作者 HU Lishun 1 , WANG Sijing 2 , HUANG Yan 2 , XUE Junli 1 ( 1 Fuels and Emissions Lab , GE Global Research Shanghai , Shanghai , China 2 GE Energy-Power & Water , Shanghai , China ) 《化工进展》 EI CAS CSCD 北大核心 2012年第S1期298-301,共4页
The paper described the coking plant and Lurgi gasifier plant waste water types and characteristics , comparing the COD and ammonia-N level in different source of waste water in the plant.The currently maturity coking... The paper described the coking plant and Lurgi gasifier plant waste water types and characteristics , comparing the COD and ammonia-N level in different source of waste water in the plant.The currently maturity coking plant waste water treatment method was statement in the paper and analyzed the pros and cons of each method.The primary cost analysis of each type of waste water treatment was also completed in the paper.According to these analyses , recommendation was prepared for coking plant and Lurgi gasifier plant waste water treatment. 展开更多
关键词 COD Lurgi gasifier plant waste water treatment Overview coking plant SCWO FIGURE
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基于Water Bomb折纸结构的软体机器鱼设计与性能分析
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作者 张宇 楚凯 +3 位作者 舒申 王家梁 周浩 胡俊峰 《工程设计学报》 北大核心 2025年第3期326-333,共8页
目前,以刚性材料为主体制作的机器鱼在水中具有良好的控制精度和较快的游动速度,但由于刚性材料自身的刚度较高,机器鱼通常无法很好地适应水中的狭窄通道。为了解决上述问题,将折纸结构应用于机器鱼的结构设计,设计了一种可在水中通过... 目前,以刚性材料为主体制作的机器鱼在水中具有良好的控制精度和较快的游动速度,但由于刚性材料自身的刚度较高,机器鱼通常无法很好地适应水中的狭窄通道。为了解决上述问题,将折纸结构应用于机器鱼的结构设计,设计了一种可在水中通过狭窄通道且具有良好游动性能的软体机器鱼。该机器鱼由头部、躯干和尾部组成,其中:躯干部分采用Water Bomb折纸结构,利用折纸结构的收缩和膨胀来实现躯干部分的径向变化;尾部利用软体折纸驱动器的弯曲来实现摆动,从而实现机器鱼的前行和转弯。通过实验测得了机器鱼在水箱中的运动情况,其最高游动速度为72.67 mm/s,最快转向速度为10.67 (°)/s,且能在最大负载为150 g的条件下稳定运动。结果表明,所设计的机器鱼不仅可以在水中灵活运动,而且能够利用躯干部分的折叠特性通过部分狭窄通道和障碍。这为软体机器鱼的设计与研究提供了一种新思路。 展开更多
关键词 软体机器鱼 软体折纸驱动器 water Bomb折纸结构 折叠特性
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Effect of hybrid type of fibers on the mechanical properties of stabilized sand with coal waste and cement
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作者 AFRAKOTI Mobina Taslimi Paein CHOOBBASTI Asskar Janalizadeh +1 位作者 KUTANAEI Saman Soleimani VAFAEI Ali 《Journal of Central South University》 CSCD 2024年第11期4276-4292,共17页
Coal waste(CW)could be used for soil stabilization due to the pozzolanic elements it contains.There hasn’t been much investigation into how different fibers affect the mechanical qualities of stabilized sand,although... Coal waste(CW)could be used for soil stabilization due to the pozzolanic elements it contains.There hasn’t been much investigation into how different fibers affect the mechanical qualities of stabilized sand,although adding fibers of any kind to soils may improve the soil because of fiber characteristics like rigidity.For this reason,several tests were carried out on sand that contained 6%cement(by dry weight of used sand),5 wt%CW,0 wt%,0.25 wt%,and 0.50 wt%fiber,as well as the unconfined compressive strength(UCS)test,indirect tensile strength(ITS)test,unconsolidated undrained(UU)triaxial test,scanning electron microscope(SEM)test and ultrasonic pulse velocity(UPV)test.The results showed that in comparison to other fiber reinforced mix designs,the specimen reinforced with 0.5%fibers and the mix design of 0.25 wt%glass and 0.25 wt%polypropylene(PP)fibers exhibited the maximum strength.Examining the impact of fiber type found that glass fibers influence PP strength more favorably than other fiber types.The use of PP fibers is an excellent solution for the problem of large strains in design processes,while adding glass fibers is considered a suitable treatment for issues related to small strains. 展开更多
关键词 coal waste CEMENT unconfined compressive strength ultrasonic pulse velocity
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Study on Domestic Solid Waste Water and Water Quality of Sari City,Mazandaran
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作者 Ahmadi Omolbanin Hasanzadeh Hosseinabadi Hasan 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期182-182,共1页
The present study is aimed at calculating domestic solid waste water in Sari city,Mazandaran.Solid waste management mainly involves management of activities that are engineering oriented such as waste generation,stora... The present study is aimed at calculating domestic solid waste water in Sari city,Mazandaran.Solid waste management mainly involves management of activities that are engineering oriented such as waste generation,storage,collection,transportation,operation of processing and disposal facilities.A small composting unit is suggested for the composting of solid waste in community or colony level so that the community committee itself can maintain the composting unit.The study is to analyze the solid waste disposal system and suggest suitable modification in the present system to improve the 展开更多
关键词 environment waste water water quality
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Waste heat water pumping model with direct contact cooling
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作者 Kittiwoot Sutthivirode Naris Pratinthong +2 位作者 Pichai Namprakai Natthaphon Roonprasang Taveewat Suparos 《Journal of Central South University》 SCIE EI CAS 2014年第10期3896-3910,共15页
The performance of a patented water pumping model with steam-air power was presented, which operates automatically by direct contact cooling method. The main objective was to study feasibility of a pumping model for u... The performance of a patented water pumping model with steam-air power was presented, which operates automatically by direct contact cooling method. The main objective was to study feasibility of a pumping model for underground water. In this model, a heater installed within the heat tank represented sources of waste heat as energy input for finding appropriate conditions of the 10 L pump model. The system operation had five stages: heating, pumping, vapor flow, cooling, and water suction. The overall water heads of 3, 4.5, 6 and 7.5 m were tested. At the same time, it was found that the pump with 50% air volume is sufficient for pumping water to a desired level. In the experiment, the temperatures in the heating and pumping stages were 100-103 ℃and 80-90 ℃, respectively. The pressure in the pumping stage was 12-18 kPa, and the pressure in the suction stage was about-80 kPa, sufficient for the best performance. It could pump 170 L of water at a 2 m suction head, 120 L at a 3.5 m suction head, 100 L at a 5 m suction head, and 65 L at a 6.5 m suction head in 2 h. A mathematical model for larger pumps was also presented, which operates nearly the same as the present system. Economic analysis of the 10 L pump was also included. 展开更多
关键词 direct contact cooling driving tank steam-air power liquid piston waste heat
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The chitosan encapsulation strategy inhibits the dissolution of MoS_(2)/ZnO nanoparticles in water disinfection
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作者 Yutao Xie Yunpeng Yu Feng Gao 《中国科学技术大学学报》 北大核心 2025年第3期28-38,27,I0002,共13页
The combination of solar disinfection and photocatalysis technology presents a viable solution for eliminating harmful pathogenic microorganisms from water.However,some photocatalysts(e.g.,zinc oxide-based composites)... The combination of solar disinfection and photocatalysis technology presents a viable solution for eliminating harmful pathogenic microorganisms from water.However,some photocatalysts(e.g.,zinc oxide-based composites)are susceptible to pH-dependent dissolution in water,which can result in the loss of photocatalysts and additional environ-mental pollution.To obtain zinc oxide-based composites with low dissolution and high antibacterial efficiency for pho-tocatalytic water disinfection,we prepared MoS_(2)/ZnO@CS composites via a precipitation method to encapsulate chitosan(CS)around MoS_(2)/ZnO.The amino groups in the CS molecules act as storerooms for hydrogen ions,which inhibits the dissolution of zinc oxide.In addition,the MoS_(2)/ZnO@CS composites exhibit high production of reactive oxygen species(ROS)and broad-spectrum antibacterial activity under simulated solar irradiation(0.1 W·cm^(-2)).This makes it an excellent antibacterial agent for solar disinfection in water treatment. 展开更多
关键词 ZnO MoS_(2) CHITOSAN ANTIBACTERIAL water disinfection
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Water-promoted green synthesis of heterocyclicβ-ketosulfides
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作者 GU Wen ZHANG Shu-ting +2 位作者 YANG Fei ZUO Yi-wei ZHAO Zhi-gang 《化学研究与应用》 北大核心 2025年第5期1274-1287,共14页
A strategy for the green synthesis of heterocyclicβ-ketosulfides via nucleophilic substitution ofα-halogenated ketone with het-eroaryl thiols in water media is presented.Compared with the available literature report... A strategy for the green synthesis of heterocyclicβ-ketosulfides via nucleophilic substitution ofα-halogenated ketone with het-eroaryl thiols in water media is presented.Compared with the available literature reports,this new method had the advantages of base-free,additives-free,simple operation,mild condition,greenness,high efficiency,tolerance of a broad scope of substrates.Furth-more,the reaction could easily be scaled up in gram scale and the products also could easily transformed to other useful organic compounds.Mechanism investigation indicated that the tautomerism of pyrimidine-2-thiol to pyrimidine-2(1H)-thione and the hy-drogen bonds played important roles in the reaction. 展开更多
关键词 green synthesis water media heterocyclicβ-ketosulfides base-free
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Infrared spectroscopic analysis of O-H bond dynamics in one-dimensional confined water and bulk water
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作者 ZHANG Lei WANG Tian-Qi FAN Yan-Ping 《红外与毫米波学报》 北大核心 2025年第1期78-85,共8页
In sub nanometer carbon nanotubes,water exhibits unique dynamic characteristics,and in the high-frequency region of the infrared spectrum,where the stretching vibrations of the internal oxygen-hydrogen(O-H)bonds are c... In sub nanometer carbon nanotubes,water exhibits unique dynamic characteristics,and in the high-frequency region of the infrared spectrum,where the stretching vibrations of the internal oxygen-hydrogen(O-H)bonds are closely related to the hydrogen bonds(H-bonds)network between water molecules.Therefore,it is crucial to analyze the relationship between these two aspects.In this paper,the infrared spectrum and motion characteristics of the stretching vibrations of the O-H bonds in one-dimensional confined water(1DCW)and bulk water(BW)in(6,6)single-walled carbon nanotubes(SWNT)are studied by molecular dynamics simulations.The results show that the stretching vibrations of the two O-H bonds in 1DCW exhibit different frequencies in the infrared spectrum,while the O-H bonds in BW display two identical main frequency peaks.Further analysis using the spring oscillator model reveals that the difference in the stretching amplitude of the O-H bonds is the main factor causing the change in vibration frequency,where an increase in stretching amplitude leads to a decrease in spring stiffness and,consequently,a lower vibration frequency.A more in-depth study found that the interaction of H-bonds between water molecules is the fundamental cause of the increased stretching amplitude and decreased vibration frequency of the O-H bonds.Finally,by analyzing the motion trajectory of the H atoms,the dynamic differences between 1DCW and BW are clearly revealed.These findings provide a new perspective for understanding the behavior of water molecules at the nanoscale and are of significant importance in advancing the development of infrared spectroscopy detection technology. 展开更多
关键词 one-dimensional confined water infrared spectroscopy hydrogen bonds
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Corrigendum to“Mechanistic Insights into Water-Mediated CO_(2)Electrochemical Reduction Reactions on Cu@C_(2)N Catalysts:A Theoretical Study”[Acta Physico-Chimica Sinica(2024)40,2303040]
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《物理化学学报》 北大核心 2025年第5期144-144,共1页
Hanyu Xu 1,Xuedan Song 1,*,Qing Zhang 1,Chang Yu 1,Jieshan Qiu 1,2,*1 Liaoning Key Lab for Energy Materials and Chemical Engineering,State Key Laboratory of Fine Chemicals,School of Chemical Engineering,Dalian Univers... Hanyu Xu 1,Xuedan Song 1,*,Qing Zhang 1,Chang Yu 1,Jieshan Qiu 1,2,*1 Liaoning Key Lab for Energy Materials and Chemical Engineering,State Key Laboratory of Fine Chemicals,School of Chemical Engineering,Dalian University of Technology,Dalian 116024,Liaoning Province,China. 展开更多
关键词 chemical engineeringdalian theoretical study water mediated Cu C N catalysts fine chemicalsschool CO electrochemical reduction chemical engineeringstate
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Effect of water on dynamic mechanical properties of coal under different depth stress conditions
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作者 LI Sheng-wei GAO Ming-zhong +2 位作者 LI Ye-xue WANG Jun ZENG Gang 《Journal of Central South University》 2025年第1期220-228,共9页
Coal seam water injection in tunnels is an effective technical measure for preventing coal mine rock bursts.This study used the improved split Hopkinson pressure bar(SHPB)to apply three equal static stresses to water-... Coal seam water injection in tunnels is an effective technical measure for preventing coal mine rock bursts.This study used the improved split Hopkinson pressure bar(SHPB)to apply three equal static stresses to water-saturated coal to simulate the initial stress environment of coal at different depths.Then,dynamic mechanical experiments were conducted on the saturated coal at different depths to investigate the effects of water saturation and depth on the coal samples’dynamic mechanical properties.Under uniaxial compression and without lateral compression,the strength of coal samples decreased to varying degrees in the saturated state;under different depth conditions,the dynamic strength of coal in the saturated state decreased compared with that in the natural state.However,compared with that at 0 m,the reduction in the strength of coal under the saturated condition at 200,400,600,and 800 m was significantly reduced.The findings of this study provide a basic theoretical foundation for the prevention and control of dynamic coal mine disasters. 展开更多
关键词 COAL mining depths water saturation SHPB dynamic compressive strength
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Surface-covering water significantly amplifies the explosion impulse of shallow buried explosives
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作者 Zhenyu Zhao Wenbo Gao +6 位作者 Jianwei Ren Zihan Lan Zhiyang Zhang Huiyao Gao Chao He Changye Ni Tianjian Lu 《Defence Technology(防务技术)》 2025年第6期156-172,共17页
While the moisture content of soil affects significantly the blast impulse of shallow buried explosives,the role of surface-covering water(SCW)on soil in such blast impulse remains elusive.A combined experimental and ... While the moisture content of soil affects significantly the blast impulse of shallow buried explosives,the role of surface-covering water(SCW)on soil in such blast impulse remains elusive.A combined experimental and numerical study has been carried out to characterize the effect of SCW on transferred impulse and loading magnitude of shallow buried explosives.Firstly,blast tests of shallow buried explosives were conducted,with and without the SCW,to quantitatively assess the blast loading impulse.Subsequently,finite element(FE)simulations were performed and validated against experimental measurement,with good agreement achieved.The validated FE model was then employed to predict the dynamic response of a fully-clamped metallic circular target,subjected to the explosive impact of shallow buried explosives with SCW,and explore the corresponding physical mechanisms.It was demonstrated that shallow buried explosives in saturated soil generate a greater impulse transferred towards the target relative to those in dry soil.The deformation displacement of the target plate is doubled.Increasing the height of SCW results in enhanced center peak deflection of the loaded target,accompanied by subsequent fall,due to the variation of deformation pattern of the loaded target from concentrated load to uniform load.Meanwhile,the presence of SCW increases the blast impulse transferred towards the target by three times.In addition,there exists a threshold value of the burial depth that maximizes the impact impulse.This threshold exhibits a strong sensitivity to SCW height,decreasing with increasing SCW height.An empirical formula for predicting threshold has been provided.Similar conclusions can be drawn for different explosive masses.The results provide technical guidance on blast loading intensity and its spatial distribution considering shallow buried explosives in coast-land battlefields,which can ultimately contribute to better protective designs. 展开更多
关键词 Shallow buried explosives Fluid-structure interaction Surface-covering water Impulse distribution
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Study of the explosion load characteristics and structural response law under a cabin water mist environment: Experimental tests and simulations
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作者 Xiaobin Li Ya Zhang +4 位作者 Yiheng Zhang Hai Huang Zhiping Wang Xingxing Wu Wei Chen 《Defence Technology(防务技术)》 2025年第7期387-404,共18页
To investigate the explosion load characteristics and structural response law in a water mist environment in a cabin,explosion experiments are carried out.The weakening rates of the initial peak overpressure,quasistat... To investigate the explosion load characteristics and structural response law in a water mist environment in a cabin,explosion experiments are carried out.The weakening rates of the initial peak overpressure,quasistatic pressure and structural residual deflection increase with increasing working pressure of the water mist nozzle.Specifically,the weakening rate of the initial peak overpressure ranges from 7.8%to 31.0%,the quasistatic pressure weakening rate ranges from 29.2%to 41.0%,and the weakening rate of the center of the plate residual deflection ranges from 10.8%to 34.4%under the various working pressures of the nozzles.To further explore the effect of water mist explosion suppression,a method for three-dimensional numerical simulations of water mist weakening the explosion shock wave is established to explore the explosion load characteristics of the compartment and the bulkhead response law.On the basis of the dimension analysis method,empirical formulas are derived to predict the residual deflection thickness in the center of the bulkheads.These findings provide the fundamental basis for the appli-cation of water mist in anti-explosive protection. 展开更多
关键词 Cabin explosion Blast response Fluidesolid coupling Load weakening water mist suppression
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In situ fabrication of hierarchical NiX@CNT:An efficient bifunctional electrocatalyst for water splitting
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作者 ZHANG Bai-qing YIN Zhuo-xun +5 位作者 MA Xin-zhi ZHOU Yang LI Jin-long WANG Yu-ping WAN Li-juan MA Zhan-chun 《Journal of Central South University》 2025年第6期2114-2128,共15页
Developing efficient,durable,and precious metal-free electrocatalysts is currently a huge challenge.In this article,through a simple one-step high-temperature pyrolysis method,by incorporating various non-metallic ele... Developing efficient,durable,and precious metal-free electrocatalysts is currently a huge challenge.In this article,through a simple one-step high-temperature pyrolysis method,by incorporating various non-metallic element atoms,we prepared four different NiX(X=Cl_(2),(CH_(3)COO)_(2),(NO_(3))2,SO_(4))@CNT catalysts.Additionally,by adjusting the temperature,these four materials were expanded into twelve catalyst materials for comparative optimization of hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)activity.Ultimately,Ni(NO_(3))2@CNT-900 typically exhibits superior OER and HER activity.In 1 mol/L KOH solution with a current density of 10 mA/cm^(2),the overpotentials of HER and OER of Ni(NO_(3))2@CNT-900 are only 145 mV and 300 mV,respectively.Furthermore,the Ni(NO_(3))2@CNT-900 shows excellent durability in both HER and OER. 展开更多
关键词 water splitting ELECTROCATALYSTS hydrogen evolution reaction(HER) oxygen evolution reaction(OER)
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Improving electrochemical performance of PEM water electrolyzer by optimizing side-chain structure and content of ionomer
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作者 LYU Hong HU Ding +2 位作者 WANG Sen SUN Yong-wen ZHANG Cun-man 《Journal of Central South University》 2025年第5期1760-1774,共15页
As the proton transport channel and binder within the catalytic layer(CL),the physicochemical properties of the ionomer can affect the CL microstructure and performance of the membrane electrode assembly.In this paper... As the proton transport channel and binder within the catalytic layer(CL),the physicochemical properties of the ionomer can affect the CL microstructure and performance of the membrane electrode assembly.In this paper,we select ionomers with different side-chain lengths and investigate the effects of the side-chain structure and content of the ionomers on the performance of membrane electrode assembly(MEA).Electrochemical tests show that at a mass ratio of 10 wt.%of ionomer/Ir(I/Ir),long-side-chain(LSC)ionomer exhibits the best performance(2.141 V@2.00 A/cm^(2),while short-side-chain(SSC)ionomer is 2.208 V@2.00 A/cm^(2)).The MEA containing LSC ionomer shows better electrochemical performance than the SSC at the same I/Ir mass ratio,especially at high current density.The MEA containing LSC ionomer has a larger average pore size and porosity,which indicates that it may have better mass-transfer properties.From the analysis of voltage loss,it can be seen that LSC ionomers have a smaller ohmic impedance and mass transfer resistance than SSC ionomers.In conclusion,LSC ionomers are more conducive to water-gas transport,which can provide excellent water electrolysis performance.This article focuses on the optimization of ionomer side chains and content,which can enhance PEM water electrolysis performance at lower cost. 展开更多
关键词 water electrolysis membrane electrode assembly anode catalytic layer ionomer side-chain length voltage loss
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Application of gurney and flight of fragment calculations for water jet velocities in explosive applications
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作者 Rachel L.Bauer Tate B.Friedrich Catherine E.Johnson 《Defence Technology(防务技术)》 2025年第7期68-78,共11页
This study investigates the application of Gurney and flight of fragment equations,typically used to predict metal fragment velocities,in modeling the water jet behavior.Three shotgun cartridge sizes were used as the ... This study investigates the application of Gurney and flight of fragment equations,typically used to predict metal fragment velocities,in modeling the water jet behavior.Three shotgun cartridge sizes were used as the energy source:2.59 g,5.83 g,and 7.13 g.Two configurations were tested:standard(full-barrel water load)and"negative 8"(partial water load).High-speed footage captured water column velocities,and Gurney models,including infinitely tamped and open-faced configurations,combined with the flight of fragment model were used to assess prediction accuracy.Results showed charge strength significantly affects water column velocity,with higher strengths yielding greater stability and velocity retention over distance.The infinitely tamped Gurney model closely predicted experimental velocities,deviating by as little as 1.4%for standard charges and 2.8% for negative 8 charges.Additionally,interesting dynamics such as a 1-2°rise in jet height and the rear overtaking the front was observed.These findings have significant implications for optimizing PAN disruptors and enhancing performance in high-velocity fluid applications and explosive breaching systems. 展开更多
关键词 Gurney calculations water driven projectile Flight of fragment Incompressible fluid dynamics Optical velocity measurement
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