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Breeding and Cultivation Techniques of Fly Fire,an Elite Variety of Malus micromalus
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作者 Changlin LI Li JIN +8 位作者 Fuyuan SU Yanxing YAO Xian PEI Chengxiang ZHENG Xianbao LIU Fazhi CHEN Yang QIN Hongying LIU Shoukun YANG 《Agricultural Biotechnology》 CAS 2018年第3期41-43,共3页
Fly fire is an elite variety of North American Begonia( Malus micromalus),which is characterized with dark red flowers,red young leaves,red peel,red bark,large flower amount,long flowering period and long fruit bear... Fly fire is an elite variety of North American Begonia( Malus micromalus),which is characterized with dark red flowers,red young leaves,red peel,red bark,large flower amount,long flowering period and long fruit bearing period. It is propagated mainly through grafting,and is suitable for popularization and application in the landscape of the Yangtze River basin and north of the Yangtze River. 展开更多
关键词 North American Begonia (Malus micromalus) fly fire VARIETY
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Solvothermal synthesis and adsorption performance of layered boehmite using aluminum chloride and high-alumina fly ash
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作者 Jing Wen Ruirui Yuan +2 位作者 Tao Jiang Tangxia Yu Yufan Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第6期280-290,共11页
High alumina fly ash(FAHAl)is a kind of bulk solid waste unique to China,whose availability of high-value aluminum and the threat to the environment makes its high-value utilization urgent.In this work,the alumina con... High alumina fly ash(FAHAl)is a kind of bulk solid waste unique to China,whose availability of high-value aluminum and the threat to the environment makes its high-value utilization urgent.In this work,the alumina containing leaching solution obtained from Na2CO_(3) roasting and HCl leaching of FAHAl was used as the mother liquor to prepare layered boehmite in situ.The preparation process with AlCl3 as the raw material was also compared.The formation process and mechanism of boehmite,the choice of solvent,along with the adsorption capability of Congo red were analyzed by X-ray diffraction,scanning electron microscopy,Fourier transform infrared spectroscopy,Brunauer-Emmett-Teller method and adsorption experiments.Results showed that during the preparation of layered boehmite,the precursor Al(OH)3 from the reaction of Al3+and OH-is transformed into boehmiteγ-AlOOH.The existence of ethanol is beneficial to regulate and promote the growth of boehmite crystal effectively.When water and ethanol are mixed with a volume ratio of 2:1 and used as the solvent,the maximum specific surface area of the boehmite is obtained at 135.7 m2·g^(-1),and 99.16%of Congo red can be absorbed after 10 min when AlCl3 is used as a raw material.As purified leaching solution is used as the mother liquid,the crystallinity of boehmite decreases slightly when the pH value decreases from 12.5 to 11.When pH is 11,the removal efficiency of Congo red reaches a maximum of 72.25%.This process not only achieves the extraction of aluminum and high-value utilization of FAHAl but also provides a thought to prepare layered boehmite with adsorption properties. 展开更多
关键词 HIGH-ALUMINA fly ash LAYERED BOEHMITE In-situ preparation SOLVOTHERMAL synthesis Adsorption High-value utilization
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Mechanism study of Cu(Ⅱ) adsorption from acidic wastewater by ultrasonic-modified municipal solid waste incineration fly ash
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作者 Shunda lin Yang Lu +3 位作者 Lin Zheng Ling Long Xuguang Jiang Jianhua Yan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第3期157-165,共9页
High concentrations of copper ions(Cu(Ⅱ)) in water will pose health risks to humans and the ecological environment. Therefore, this study aims to utilize ultrasonic-cured modified municipal solid waste incineration(M... High concentrations of copper ions(Cu(Ⅱ)) in water will pose health risks to humans and the ecological environment. Therefore, this study aims to utilize ultrasonic-cured modified municipal solid waste incineration(MSWI) fly ash for Cu(Ⅱ) adsorption to achieve the purpose of “treating waste by waste.” The effects of p H, adsorption time, initial concentration, and temperature on the modified MSWI fly ash’s adsorption efficiency were systematically studied in this article. The adsorption performance of the modified MSWI fly ash can be enhanced by the ultrasonic modification. At pH = 2, 3 and 4, the adsorption capacity of the modified MSWI fly ash for Cu(Ⅱ) increased by 2.7, 1.9 and 1.2 times, respectively. Furthermore, it was suggested that the adsorption process of the modified MSWI fly ash can be better simulated by the pseudo-second-order kinetic model, with a maximum adsorption capacity calculated by the Langmuir model of 24.196 mg.g-1. Additionally, the adsorption process is spontaneous,endothermic, and chemisorption-dominated from the thermodynamic studies(ΔH and ΔS > 0, ΔG < 0).Finally, the enhanced adsorption performance of the modified MSWI fly ash for Cu(Ⅱ) may be attributed to electrostatic interaction and chelation effects. 展开更多
关键词 ULTRASOUND MSWI fly ash Cu(Ⅱ) WASTEWATER ADSORPTION
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Effect of Partial Replacement of Fly Ash by Decoration Waste Powder on the Fresh and Mechanical Properties of Geopolymer Masonry Mortar
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作者 刘惠 ZHANG Ruidong +2 位作者 朱平华 WANG Xinjie CHEN Chunhong 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第3期698-704,共7页
This study aims to investigate the feasibility of using decoration waste powder(DWP)as a partial replacement for fly ash(FA)in the preparation of geopolymer masonry mortar,and to examine the effect of different DWP re... This study aims to investigate the feasibility of using decoration waste powder(DWP)as a partial replacement for fly ash(FA)in the preparation of geopolymer masonry mortar,and to examine the effect of different DWP replacement rates(0%-40%)on the fresh and mechanical properties of the mortar.The results showed that each group of geopolymer masonry mortar exhibited excellent water retention performance,with a water retention rate of 100%,which was due to the unique geopolymer mortar system and high viscosity of the alkaline activator solution.Compared to the control group,the flowability of the mortar containing lower contents of DWP(10%and 20%)was higher.However,as the DWP replacement rate further increased,the flowability gradually decreased.The DWP could absorb the free water in the reaction system of geopolymer mortar,thereby limiting the occurrence of geopolymerization reaction.The incorporation of DWP in the mortar resulted in a decrease in compressive strength compared to the mortar without DWP.However,even at a replacement rate of 40%,the compressive strength of the mortar still exceeded 15 MPa,which met the requirements of the masonry mortar.It was feasible to use DWP in the geopolymer masonry mortar.Although the addition of DWP caused some performance loss,it did not affect its usability. 展开更多
关键词 fly ash-based geopolymer decoration waste powder masonry mortar WORKABILITY compressive strength
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Experimental study on the activation of coal gasification fly ash from industrial CFB gasifiers
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作者 Qiyao Yang Xiaobin Qi +1 位作者 Qinggang Lyu Zhiping Zhu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期8-18,共11页
Coal gasification fly ash(CGFA)is an industrial solid waste from the coal circulating fluidized bed(CFB)gasification process,and it needs to be effectively disposed to achieve sustainable development of the environmen... Coal gasification fly ash(CGFA)is an industrial solid waste from the coal circulating fluidized bed(CFB)gasification process,and it needs to be effectively disposed to achieve sustainable development of the environment.To realize the application of CGFA as a precursor of porous carbon materials,the physicochemical properties of three kinds of CGFA from industrial CFB gasifiers are analyzed.Then,the activation potential of CGFA is acquired via steam activation experiments in a tube furnace reactor.Finally,the fluidization activation technology of CGFA is practiced in a bench-scale CFB test rig,and its advantages are highlighted.The results show that CGFA is characterized by a high carbon content in the range of 54.06%–74.09%,an ultrafine particle size(d50:16.3–26.1 μm),and a relatively developed pore structure(specific surface area SSA:139.29–551.97 m^(2)·g^(-1)).The proportion of micropores in CGFA increases gradually with the coal rank.Steam activation experiments show that the pore development of CGFA mainly includes three stages:initial pore development,dynamic equilibrium between micropores and mesopores and pore collapse.The SSA of lignite fly ash(LFA),subbituminous fly ash(SBFA)and anthracite fly ash(AFA)is maximally increased by 105%,13%and 72%after steam activation;the order of the largest carbon reaction rate and decomposition ratio of steam among the three kinds of CGFA is SBFA>LFA>AFA.As the ratio of oxygen to carbon during the fluidization activation of LFA is from 0.09 to 0.19,the carbon conversion ratio increases from 14.4%to 26.8%and the cold gas efficiency increases from 6.8%to 10.2%.The SSA of LFA increases by up to 53.9%during the fluidization activation process,which is mainly due to the mesoporous development.Relative to steam activation in a tube furnace reactor,fluidization activation takes an extremely short time(seconds)to achieve the same activation effect.It is expected to further improve the activation effect of LFA by regulating the carbon conversion ratio range of 27%–35%to create pores in the initial development stage. 展开更多
关键词 Circulating fluidized bed Coal gasification fly ash Steam activation Pore structure evolution Fluidization activation
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Combined use of fly ash and silica to prevent the long-term strength retrogression of oil well cement set and cured at HPHT conditions
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作者 Guo-Dong Cheng Xue-Yu Pang +4 位作者 Jin-Sheng Sun Zheng-Song Qiu Chuang-Chuang Wang Jian-Kun Qin Ning Li 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1122-1134,共13页
The long-term strength retrogression of silica-enriched oil well cement poses a significant threat to wellbore integrity in deep and ultra-deep wells, which is a major obstacle for deep petroleum and geothermal energy... The long-term strength retrogression of silica-enriched oil well cement poses a significant threat to wellbore integrity in deep and ultra-deep wells, which is a major obstacle for deep petroleum and geothermal energy development. Previous attempts to address this problem has been unsatisfactory because they can only reduce the strength decline rate. This study presents a new solution to this problem by incorporating fly ash to the traditional silica-cement systems. The influences of fly ash and silica on the strength retrogression behavior of oil well cement systems directly set and cured under the condition of 200°C and 50 MPa are investigated. Test results indicate that the slurries containing only silica or fly ash experience severe strength retrogression from 2 to 30 d curing, while the slurries containing both fly ash and silica experience strength enhancement from 2 to 90 d. The strength test results are corroborated by further evidences from permeability tests as well as microstructure analysis of set cement. Composition of set cement evaluated by quantitative X-ray diffraction analyses with partial or no known crystal structure(PONKCS) method and thermogravimetry analyses revealed that the conversion of amorphous C-(A)-S-H to crystalline phases is the primary cause of long-term strength retrogression.The addition of fly ash can reduce the initial amount of C-(A)-S-H in the set cement, and its combined use with silica can prevent the crystallization of C-(A)-S-H, which is believed to be the working mechanism of this new admixture in improving long-term strength stability of oil well cement systems. 展开更多
关键词 fly ash Long-term strength retrogression High temperature Quantitative X-ray diffraction(QXRD) Partial or no known crystal structure(PONKCS)
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Barley chitinase genes expression revamp resistance against whitefly (Bemisia Tabaci) in transgenic cotton (Gossypium hirsutum L.)
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作者 BASHIR Samina YAQOOB Amina +7 位作者 BASHIR Rohina BUKHARI Shanila SHAHID Naila AZAM Saira BAKHSH Allah HUSNAIN Tayyab SHAHID Ahmad Ali RAO Abdul Qayyum 《Journal of Cotton Research》 CAS 2024年第1期90-100,共11页
Background Chitinase is an enzyme that hydrolyzes chitin,a major component of the exoskeleton of insects,including plant pests like whiteflies.The present study aimed to investigate the expression of chemically synthe... Background Chitinase is an enzyme that hydrolyzes chitin,a major component of the exoskeleton of insects,including plant pests like whiteflies.The present study aimed to investigate the expression of chemically synthesized barley ch1 and chi2 genes in cotton(Gossypium hirsutum)through Agrobacterium-mediated transformation.Fifty-five putative transgenic cotton plants were obtained,out of which fifteen plants successfully survived and were shifted to the field.Using gene-specific primers,amplification of 447 bp and 401 bp fragments confirmed the presence of the ch1 and chi2 genes in five transgenic cotton plants of the T0 generation.These five plants were further evalu-ated for their mRNA expression levels.The T0 transgenic cotton plants with the highest mRNA expression level and better yield performance in field,were selected to raise their subsequent progenies.Results The T1 cotton plants showed the highest mRNA expression levels of 3.5-fold in P10(2)for the ch1 gene and 3.7-fold in P2(1)for the chi2 gene.Fluorescent in situ hybridization(FISH)confirmed a single copy number of ch1 and chi2(hemizygous)on chromosome no.6.Furthermore,the efficacy of transgenes on whitefly was evaluated through an insect bioassay,where after 96 h of infestation,mortality rates of whitefly were calculated to be 78%–80%in transgenic cotton plants.The number of eggs on transgenic cotton plants were calculated to be 0.1%–0.12 per plant compared with the non-transgenic plants where egg number was calculated to be 0.90–1.00 per plant.Conclusion Based on these findings,it can be concluded that the chemically synthesized barley chitinase genes(ch1 and chi2)have the potential to be effective against insects with chitin exoskeletons,including whiteflies.The transgenic cotton plants expressing these genes showed increased resistance to whiteflies,resulting in reduced egg numbers and higher mortality rates. 展开更多
关键词 CHITINASE Cotton White fly TRANSGENE BIOASSAY
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An Opposition-Based Learning-Based Search Mechanism for Flying Foxes Optimization Algorithm
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作者 Chen Zhang Liming Liu +5 位作者 Yufei Yang Yu Sun Jiaxu Ning Yu Zhang Changsheng Zhang Ying Guo 《Computers, Materials & Continua》 SCIE EI 2024年第6期5201-5223,共23页
The flying foxes optimization(FFO)algorithm,as a newly introduced metaheuristic algorithm,is inspired by the survival tactics of flying foxes in heat wave environments.FFO preferentially selects the best-performing in... The flying foxes optimization(FFO)algorithm,as a newly introduced metaheuristic algorithm,is inspired by the survival tactics of flying foxes in heat wave environments.FFO preferentially selects the best-performing individuals.This tendency will cause the newly generated solution to remain closely tied to the candidate optimal in the search area.To address this issue,the paper introduces an opposition-based learning-based search mechanism for FFO algorithm(IFFO).Firstly,this paper introduces niching techniques to improve the survival list method,which not only focuses on the adaptability of individuals but also considers the population’s crowding degree to enhance the global search capability.Secondly,an initialization strategy of opposition-based learning is used to perturb the initial population and elevate its quality.Finally,to verify the superiority of the improved search mechanism,IFFO,FFO and the cutting-edge metaheuristic algorithms are compared and analyzed using a set of test functions.The results prove that compared with other algorithms,IFFO is characterized by its rapid convergence,precise results and robust stability. 展开更多
关键词 flying foxes optimization(FFO)algorithm opposition-based learning niching techniques swarm intelligence metaheuristics evolutionary algorithms
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Study on Fly Ash Based Porous Ceramsite as Biological Filter Media
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作者 Ruigang WANG Shuo WANG +1 位作者 Weijie LI Hailong LIU 《Agricultural Biotechnology》 2024年第1期71-73,共3页
Using fly ash as a raw material,porous ceramic particles with an apparent density of 1.21 g/cm^(3),a visible porosity of 51.03%,and a specific surface area of 4.26 m^(2)/g were prepared and used as biofilter materials... Using fly ash as a raw material,porous ceramic particles with an apparent density of 1.21 g/cm^(3),a visible porosity of 51.03%,and a specific surface area of 4.26 m^(2)/g were prepared and used as biofilter materials for wastewater treatment.Through SEM,XRD analysis,and heavy metal leaching analysis,it was found that porous ceramsite were porous materials with rough surfaces.After calcination,the newly formed mineral was silicate calcium feldspar.The heavy metal concentration in the leaching solution of porous ceramsite met the national surface water quality requirements.The treatment of domestic sewage showed that the volumetric loads of COD Cr,NH_(4)^(+)-N,and TN removed by the aerated biofilter were 5.23,0.98,and 0.35 kg/(m^(3)·d),respectively,with removal rates of 85.46%,96.13%,and 32.31%. 展开更多
关键词 Porous ceramsite Domestic sewage fly ash
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An Overview of the Achievements of Modern Research on the Flying Shadow Pavilion Pictorial
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作者 CHEN Honghui 《Cultural and Religious Studies》 2024年第2期118-122,共5页
The current academic research on the Dian Shi Zhai Pictorial founded in 1884 has been perfected,but there is very little research on the Flying Shadow Pavilion Pictorial,which can be said to be derived from Dian Shi Z... The current academic research on the Dian Shi Zhai Pictorial founded in 1884 has been perfected,but there is very little research on the Flying Shadow Pavilion Pictorial,which can be said to be derived from Dian Shi Zhai Pictorial terms of both content and form,and which was founded by the Haiist painter Wu Youru in 1890 in order to reward the increasing number of admirers,but it is still in the initial stage.Flying Shadow Pavilion Pictorial consisted of four parts:pictures of ladies in Shanghai costumes,news about current affairs,pictures of animals,and compilations of women,each of which was accompanied by the then popular notebooks,which were popular at the time among the then readers because of the matching of pictures with text and the mixing of narratives and discussions.This paper takes Flying Shadow Pavilion Pictorial as the main object,summarizes the existing literature about Flying Shadow Pavilion Pictorial,points out the deficiencies of the current research on this basis,and points out the development trend of Flying Shadow Pavilion Pictorial in the future research. 展开更多
关键词 flying Shadow Pavilion Pictorial Dian Shi Zhai Pictorial Late Qing Dynasty’s pictorial
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Fire Detection Method Based on Improved Fruit Fly Optimization-Based SVM 被引量:4
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作者 Fangming Bi Xuanyi Fu +3 位作者 Wei Chen Weidong Fang Xuzhi Miao Biruk Assefa 《Computers, Materials & Continua》 SCIE EI 2020年第1期199-216,共18页
Aiming at the defects of the traditional fire detection methods,which are caused by false positives and false negatives in large space buildings,a fire identification detection method based on video images is proposed... Aiming at the defects of the traditional fire detection methods,which are caused by false positives and false negatives in large space buildings,a fire identification detection method based on video images is proposed.The algorithm first uses the hybrid Gaussian background modeling method and the RGB color model to perform fire prejudgment on the video image,which can eliminate most non-fire interferences.Secondly,the traditional regional growth algorithm is improved and the fire image segmentation effect is effectively improved.Then,based on the segmented image,the dynamic and static features of the fire flame are further analyzed and extracted in the area of the suspected fire flame.Finally,the dynamic features of the extracted fire flame images were fused and classified by improved fruit fly optimization support vector machine,and the recognition results were obtained.The video-based fire detection method proposed in this paper greatly improves the accuracy of fire detection and is suitable for fire detection and identification in large space scenarios. 展开更多
关键词 fire detection image segmentation feature extraction fruit fly optimization support vector machine
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A Study on the Effect of Low Calcium Ultra-fine Fly Ash as a Partial Sustainable Supplementary Material to Cement in Self-compacting Concrete 被引量:2
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作者 Adapala Sunny Suprakash Karthiyaini S 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第2期330-341,共12页
The aim and scope of the present study were to determine the efficacy of UFFA in evaluating the workability,static and dynamic stabilization properties,retention period,and slump loss of SCC systems in their fresh sta... The aim and scope of the present study were to determine the efficacy of UFFA in evaluating the workability,static and dynamic stabilization properties,retention period,and slump loss of SCC systems in their fresh state,as well as their compressive strength at various ages.Microstructure(SEM and XRD)of blended SCC systems were studied.Also,the thermogravimetry behavior of blended SCC specimens were researched.According to the evaluated results,incorporating up to 20%UFFA into fresh concrete improved its performance due to its engineered fine particle size and spherical geometry,both of which contribute to the enhancement of characteristics.Blends of 25%and 30%of UFFA show effect on the water-binder ratio and chemical enhancer dosage,resulting in a loss of homogeneity in fresh SCC systems.The reduced particle size,increased amorphous content,and increased surface area all contribute to the pozzolanic reactivity of the early and later ages,resulting in denser packing and thus an increase in compressive strength.The experimental results indicate that UFFA enhances the properties of SCC in both its fresh and hardened states,which can be attributed to the particles’fineness and their relative effect on SCC. 展开更多
关键词 ultra fine fly ash self-compacting concrete WORKABILITY SEGREGATION compressive strength microstructure TGA
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Enhancing fly ash utilization in backfill materials treated with CO_(2)carbonation under ambient conditions 被引量:1
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作者 Ichhuy Ngo Liqiang Ma +1 位作者 Jiangtao Zhai Yangyang Wang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第3期323-337,共15页
The environmental concerns resulting from coal-fired power generation that produces large amounts of CO_(2)and fly ash are of great interest.To mitigate,this study aims to develop a novel carbonated CO_(2)-fly ash-bas... The environmental concerns resulting from coal-fired power generation that produces large amounts of CO_(2)and fly ash are of great interest.To mitigate,this study aims to develop a novel carbonated CO_(2)-fly ash-based backfill(CFBF)material under ambient conditions.The performance of CFBF was investigated for different fly ash-cement ratios and compared with non-CO_(2)reacted samples.The fresh CFBF slurry conformed to the Herschel-Bulkley model with shear thinning characteristics.After carbonation,the yield stress of the fresh slurry increased significantly by lowering fly ash ratio due to gel formation.The setting times were accelerated,resulting in approximately 40.6%of increased early strength.The final strength decreased when incorporating a lower fly ash ratio(50%and 60%),which was related to the existing heterogeneous pores caused by rapid fluid loss.The strength increased with fly ash content above 70%because additional C-S(A)-H and silica gels were characterized to precipitate on the grain surface,so the binding between particles increased.The C-S(A)-H gel was developed through the pozzolanic reaction,where CaCO_(3)was the prerequisite calcium source obtained in the CO_(2)-fly ash reaction.Furthermore,the maximum CO_(2)uptake efficiency was 1.39 mg-CO_(2)/g-CFBF.The CFBF material is feasible to co-dispose CO_(2)and fly ash in the mine goaf as negative carbon backfill materials,and simultaneously mitigates the strata movement and water lost in post-subsurface mining. 展开更多
关键词 fly ash utilization CO_(2)carbonation Ambient conditions Water conservative backfill mining Negative carbon backfill materials
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An Experimental Investigation on Workability and Bleeding Behaviors of Cement Pastes Doped with Nano Titanium Oxide (n-TiO 2) Nanoparticles and FlyAsh 被引量:1
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作者 FatihÇelik Oğuzhan Yıldız +1 位作者 AndaçBaturÇolak Samet Mufit Bozkır 《Fluid Dynamics & Materials Processing》 EI 2023年第1期135-158,共24页
In this study,the workability of cement-based grouts containing n-TiO 2 nanoparticles and fly ash has been investigated experimentally.Several characteristic quantities(including,but not limited to,the marsh cone flow... In this study,the workability of cement-based grouts containing n-TiO 2 nanoparticles and fly ash has been investigated experimentally.Several characteristic quantities(including,but not limited to,the marsh cone flow time,the mini slump spreading diameter and the plate cohesion meter value)have been measured for different percentages of these additives.The use of fly ash as a mineral additive has been found to result in improvements in terms of workability behavior as expected.Moreover,if nano titanium oxide is also used,an improvement can be obtained regarding the bleeding values for the cement-based grout mixes.Using such experimental data,a multi-layer perceptron artificial neural network model has been developed(5 neurons in the hidden layer of the network model have been developed using a total of 42 experimental data).70%of the data employed in this model have been used for training,15%for validation and 15%for the test phase.The results demonstrate that the artificial neural network model can predict Marsh cone flow time,mini slump spreading diameter and plate cohesion meter values with an average error of 0.15%. 展开更多
关键词 Nano titanium oxide fly ash workability of grouts BLEEDING stability of grouts ANN
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Characterization and mode of occurrence of rare earth elements and yttrium in fly and bottom ash from coal-fired power plants in Java,Indonesia
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作者 Dea Anisa Ayu Besari Ferian Anggara +1 位作者 Widya Rosita Himawan T.B.M.Petrus 《International Journal of Coal Science & Technology》 EI CAS CSCD 2022年第2期229-244,共16页
Fly and bottom ash(FABA)produced primarily from coal combustion in a coal-fred power plant consists of fne particles of the organic and inorganic mixture and trace elements.Eight FABA samples from coal-fred power plan... Fly and bottom ash(FABA)produced primarily from coal combustion in a coal-fred power plant consists of fne particles of the organic and inorganic mixture and trace elements.Eight FABA samples from coal-fred power plants in Java,Indonesia,had been collected for composition and rare earth element and Yttrium(REY)mode of occurrence identifcation.The geochemical composition of both major and trace elements was determined by inductively coupled plasma-mass spectrometry/atomic emission spectrometry(ICP-MS/AES).Furthermore,the composition of FABA was identifed by petrography with refected light microscopy and X-ray difraction(XRD)analysis.Simultaneously,scanning electron microscope determines the mode of occurrence of REY with an energy-dispersive X-ray(SEM–EDX).The study fnds that the inorganic component of FABA consists of glass,Fe–Mg spinel,mullite,quartz,Fe-oxide mineral,and K-feldspar.In contrast,the organic component is dominated by unburned coal.Glass is the most abundant component with cenospheres as major and pleiospheres as minor constituents.Trace elements analysis indicates REY concentration with heavy REY(HREY)distribution pattern.Moreover,SEM–EDX analysis results show that Yttrium(Y)occurs in glass and has a low concentration in spinel.From the mode occurrence of REY,in particular Yttrium,it can be predicted that alkaline fusion followed by acid leaching will be the most appropriate extraction method to extract REY from Indonesian FABA. 展开更多
关键词 REY fly ash Bottom ash GLASS Indonesia
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Waste fly ash-ZnO as a novel sunlight-responsive photocatalyst for dye discoloration
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作者 Leena V.Bora Sonal P.Thakkar +1 位作者 Kevin S.Vadaliya Nisha V.Bora 《Water Science and Engineering》 EI CAS CSCD 2023年第1期76-82,共7页
Treating waste with a waste material using freely available solar energy is the most effective way towards sustainable future.In this study,a novel photocatalyst,partly derived from waste material from the coal indust... Treating waste with a waste material using freely available solar energy is the most effective way towards sustainable future.In this study,a novel photocatalyst,partly derived from waste material from the coal industry,was developed.Fly ash hybridized with ZnO(FAeZn)was synthesized as a potential photocatalyst for dye discoloration.The synthesized photocatalyst was characterized by X-ray diffraction,scanning electron microscopy,transmission electron microscopy,and ultravioletevisible/near infra-red spectroscopy.The photocatalytic activity was examined with the discoloration of methylene blue used as synthetic dye wastewater.All the experiments were performed in direct sunlight.The photocatalytic performance of FAeZn was found to be better than that of ZnO and the conventionally popular TiO2.The LangmuireHinshelwood model rate constant values of ZnO,TiO2,and FAeZn were found to be 0.016 min1,0.017 min1,and 0.020 min1,respectively.There were two reasons for this:(1)FAeZn was able to utilize both ultraviolet and visible parts of the solar spectrum,and(2)its BrunauereEmmetteTeller surface area and porosity were significantly enhanced.This led to increased photon absorption and dye adsorption,thus exhibiting an energy-efficient performance.Therefore,FAeZn,partly derived from waste,can serve as a suitable material for environmental remediation and practical solar energy applications. 展开更多
关键词 PHOTOCATALYST ZNO fly ash GEOPOLYMER Wastewater treatment Methylene blue
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Molecular mechanism of fly ash affecting the performance of cemented backfill material
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作者 Shuo Yang Jiangyu Wu +5 位作者 Hongwen Jing Xinguo Zhang Weiqiang Chen Yiming Wang Qian Yin Dan Ma 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第8期1560-1572,共13页
The great challenge of cemented tailings backfill(CTB)is difficult simultaneously maintaining its excellent mechanical properties and low cost.Fly ash(FA)can potentially address this problem and further replace cement... The great challenge of cemented tailings backfill(CTB)is difficult simultaneously maintaining its excellent mechanical properties and low cost.Fly ash(FA)can potentially address this problem and further replace cement in favor of low carbon development.However,its mechanism on CTB with low cement dosage and low Ca system remains unclear.Consequently,this study conducted uniaxial compression,Xray diffraction(XRD),and scanning electron microscopy(SEM)-energy dispersive spectrometer(EDS)tests to investigate the effect of FA dosage on the mechanical property and microstructure of CTB.A molecular model of FA-CSH was constructed to reproduce the molecular structure evolution of CTB with FA based on the test results.The influences of FA dosage and calcium/silica molar ratio(Ca/Si ratio)on the matrix strength and failure model were analyzed to reveal the mechanism of FA on calcium silicate hydrated(C-S-H).The results show that the strength of CTB increases initially and then decreases with FA dosage,and the FA supplement leads to a decrease in Ca(OH)_(2) diffraction intensity and Ca/Si ratio around the FA particles.XRD and SEM-EDS findings show that the Ca/Si ratio of C-S-H decreases with the progression of hydration.The FA-CSH model indicates that FA can reinforce the silica chain of C-S-H to increase the matrix strength.However,this enhancement is weakened by supplementing excessive FA dosage.In addition,the hydrogen bonds among water molecules deteriorate,reducing the matrix strength.A low Ca/Si ratio results in an increase in water molecules and a decrease in the ionic bonds combined with Ca^(2+).The hydrogen bonds among water molecules cannot withstand high stresses,resulting in a reduction in strength.The water absorption of the FA-CSH model is negatively correlated with the FA dosage and Ca/Si ratio.The use of optimal FA dosage and Ca/Si ratio leads to suitable water absorption,which further affects the failure mode of FA-CSH. 展开更多
关键词 fly ash cemented tailings backfill calcium/silica ratio microstructure molecular dynamics simulation
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Fabrication of a flexible microwave absorber sheet based on a composite filler with fly ash as the core filled silicone rubber
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作者 Qiuying Li Yiheng Lu Zhuoyan Shao 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第3期548-558,共11页
A new type of composite filler was designed by a modified sol-gel method using fly ash(FA),Fe(NO_(3))_(3)·9H_(2)O,and Ni(NO_(3))_(2)·6H_(2)O as raw materials.The composite filler was a spherical core-shell s... A new type of composite filler was designed by a modified sol-gel method using fly ash(FA),Fe(NO_(3))_(3)·9H_(2)O,and Ni(NO_(3))_(2)·6H_(2)O as raw materials.The composite filler was a spherical core-shell structure composed of FA as the core and NiFe_(2)O_(4)as the shell.Further,the composite filler was added into the silicone rubber to fabricate the high temperature vulcanized microwave absorption materials;X-ray diffraction,fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,and scanning electron microscope confirmed that NiFe_(2)O_(4)was successfully coated on the surface of FA and formed a uniform and continuous coating layer.As expected,silicone rubber filled with the composite filler had a minimum reflection loss of-23.8 dB at 17.5 GHz with the thickness of 1.8 mm,while the effective absorption bandwidth was as high as 12 GHz.The addition of the composite filler greatly enhanced the microwave absorption properties of the system,which was resulted from multiple losses mechanism:interface polarization losses,magnetic losses,and multiple reflection losses.Also,silicone rubber filled with the composite filler exhibited excellent thermal stability,flexibility,environmental resistance,and hydrophobicity compared with traditional silicone rubber.Therefore,this work not only responds to the green chemistry to achieve efficient FA recovery,but also devises a new strategy to prepare microwave absorption materials with strong potential for civilian applications. 展开更多
关键词 fly ash microwave absorption silicone rubber multiple losses mechanism
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Analysis of the Performances and Optimization of Polyurethane Concrete with a Large Percentage of Fly Ash
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作者 Tingting Huo Jiaquan Xue Zhi’an Fu 《Fluid Dynamics & Materials Processing》 EI 2023年第2期437-450,共14页
The properties of polyurethane concrete containing a large amount of fly ash are investigated,and accordingly,a model is introduced to account for the influence of fly ash fineness,water ratio,and loss of ignition(LOI... The properties of polyurethane concrete containing a large amount of fly ash are investigated,and accordingly,a model is introduced to account for the influence of fly ash fineness,water ratio,and loss of ignition(LOI)on its mechanical performances.This research shows that,after optimization,the concrete has a compressive strength of 20.8 MPa,a flexural strength of 3.4 MPa,and a compressive modulus of elasticity of 19.2 GPa.The main factor influencing 28 and 90 d compressive strength is fly ash content,water-binder ratio,and early strength agent content. 展开更多
关键词 Water-containing unsaturated polyurethane concrete fly ash ratio test strength test water content test mechanical properties
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Effect of CSH Crystal Nucleus on Steam-Free Cured Fly Ash Precast Concrete Components
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作者 Ruyi Luo Yanyan Hu +2 位作者 Tingshu He Xiaodong Ma Yongdong Xu 《Journal of Renewable Materials》 EI 2023年第9期3485-3500,共16页
The measures of steam curing and early-strengthening agents to promote the precast components to reach the target strength quickly can bring different degrees of damage to the concrete.Based on this,the new nanomateri... The measures of steam curing and early-strengthening agents to promote the precast components to reach the target strength quickly can bring different degrees of damage to the concrete.Based on this,the new nanomaterial CSH-the hydration product of cement effectively solves these measures’disadvantages,such as excessive energy consumption,thermal stress damage,and the introduction of external ions.In this paper,the effect of CSH on the early strength of precast fly ash concrete components was investigated in terms of setting time,workability,and mechanical properties and analyzed at the microscopic level using hydration temperature,XRD,and SEM.The results showed that under the same workability,CSH could significantly reduce the amount of admixture,shorten the final setting time,almost not affect the initial setting time,and accelerate the hydration of cement.At the optimum dose of 5%,the mechanical properties of the specimens were improved by more than 98%within 12 h of hydration,resulting in an earlier release time of 12 h and no risk of strength inversion later.The results of this paper give theoretical support to the behavior of precast components under steam-free curing. 展开更多
关键词 fly ash concrete prefabricated components steam-free curing CSH crystal nucleus TOBERMORITE
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