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Research Advance on Influencing Factors of Crop Water Use Efficiency 被引量:3
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作者 周敏 周绍松 +2 位作者 王建新 张忠武 杨景华 《Agricultural Science & Technology》 CAS 2014年第11期1967-1976,共10页
The research advance on the influencing factors of crop water use effi-ciency (WUE) was reviewed in this paper. Based on the discussion on the conno-tation of crop WUE, the influencing factors of crop WUE, such as c... The research advance on the influencing factors of crop water use effi-ciency (WUE) was reviewed in this paper. Based on the discussion on the conno-tation of crop WUE, the influencing factors of crop WUE, such as crop, environ-ment, chemicals, cultivation measures, cropping systems, etc, were elaborated. A-mong them, the species and varieties of crop, soil and chemicals were discussed in detail. 展开更多
关键词 Crop Water use efficiency Soil Influencing factor
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Influencing Factors of Total Factor Energy Efficiency in Bohai Rim Region Based on DEA-Tobit Model 被引量:1
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作者 Weifeng Gong Xiaohong Qi +2 位作者 ChuanhuiWang Wenwen Li Yang Xu 《Energy Engineering》 EI 2022年第4期1663-1679,共17页
Bohai Rim region is an important economic development area and a large carbon emission area in China.It is of great significance to explore the total factor energy efficiency and its influencing factors for the low ca... Bohai Rim region is an important economic development area and a large carbon emission area in China.It is of great significance to explore the total factor energy efficiency and its influencing factors for the low carbon transformation and high-quality development of the Bohai Rim region.Based on the total factor energy efficiency framework,the DDF-DEA model was used to calculate the total factor energy efficiency,and the internal and external differences of the total factor energy efficiency were further analyzed.The internal and external influencing factors were determined by ML index method and classical endogenous growth theory,and then the Tobit panel model was used to empirically analyze the action mechanism of all influencing factors of total factor energy efficiency in the Bohai Rim region.The results show that the pure technical efficiency,scale efficiency and technological progress among the internal influencing factors contribute to the improvement of energy efficiency in the Bohai Rim region.Industrial structure,industrial internal structure and ownership structure inhibit the improvement of energy efficiency.Energy consumption structure and energy endowment also have a negative impact on energy efficiency.Therefore,measures such as promoting technological progress,adjusting economic structure and optimizing energy structure will effectively improve total factor energy efficiency in the Bohai Rim region. 展开更多
关键词 Total factor energy efficiency influencing factors Bohai Rim region DEA-Tobit model ML index method
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Spectrum-Splitting Diffractive Optical Element of High Concentration Factor and High Optical Efficiency for Three-Junction Photovoltaics
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作者 林冬风 全保刚 +8 位作者 张秋琳 张东香 许信 叶佳声 张岩 李冬梅 孟庆波 潘丽 杨国桢 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第9期64-67,共4页
A spectrum-splitting and beam-concentrating (SSBC) diffractive optical element (DOE) for three-junction pho- tovoltaics (PV) system is designed and fabricated by five-circ/e micro-fabrication. The incident solar... A spectrum-splitting and beam-concentrating (SSBC) diffractive optical element (DOE) for three-junction pho- tovoltaics (PV) system is designed and fabricated by five-circ/e micro-fabrication. The incident solar light is efficiently split into three sub-spectrum ranges and strongly concentrated on the focal plane, which can be di- rectly utilized by suitable spectrum-matching solar cells. The system concentration factor reaches 12x. Moreover, the designed wavelengths (450nm, 550nm and 65Onto) are spatially distributed on the focal plane, in good agree- ment with the theoretical results. The average optical effic/ency of all the cells over the three designed wavelengths is 60.07%. The SSBC DOE with a high concentration factor and a high optical efficiency provides a cost-effective approach to achieve higher PV conversion efficieneies. 展开更多
关键词 of on it Spectrum-Splitting Diffractive Optical Element of High Concentration factor and High Optical efficiency for Three-Junction Photovoltaics is in for DOE been
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Efficiency of Severe Recorded Rainstorms over Maharashtra State
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作者 B.D.Kulkarni Miss Shobha Nandargi O. N. Dhar 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1995年第1期103-108,共6页
12 severe rainstorms have been experienced by different meteorological sub-divisions of Maharashtra State during the last 100-year period from 1891-1990. For each of the rainstorms efficiency factors (i.e. P/ M ratios... 12 severe rainstorms have been experienced by different meteorological sub-divisions of Maharashtra State during the last 100-year period from 1891-1990. For each of the rainstorms efficiency factors (i.e. P/ M ratios) were worked out for maximum one-day duration and for three standard areas of 1000, 5000, and 10,000 km2. Comparison of these ratios with the past has shown that the most efficient rainstorm over Maharashtra was the rainstorm of June, 1908 over the Vidarbha region whose full DAD data as well as isohyetal pattern have been given. 展开更多
关键词 Rainstonn Depth-area -duration (DAD) efficiency factor of rainstorms Probable Maximum Precipitation (PMP)
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Energy efficiency and economic growth of China:1953-2006 被引量:1
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作者 Zhang Jian 《Ecological Economy》 2009年第2期122-131,共10页
Energy plays an important role in the economic life. With the rapid development of economy, the constraint of energy on the sustainable development of economy is becoming more and more obvious. This paper just Studies... Energy plays an important role in the economic life. With the rapid development of economy, the constraint of energy on the sustainable development of economy is becoming more and more obvious. This paper just Studies the factors influencing energy efficiency of China and the relationship between energy efficiency and China's economic: growth. By using time series multivariable linear regression methods with China's relevant data from 1953 to 2006, this paper constructs the regression model to analyze the factors that would impact energy, efficiency. After that, a regression model of China's real output to capital, labor and energy e lficiency is conducted to estimate the marginal contribution of every factor to the real output to prove the fundamental influence of energy efficiency to the economic growth. In the end, some policies and recommendations are also put forward in order to improve the energy efficiency; of China. 展开更多
关键词 Energy efficiency impact factor Economic growth Input and output
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Non-viral liposome-mediated transfer of brain-derived neurotrophic factor across the blood-brain barrier 被引量:8
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作者 Ying Xing Chun-yan Wen +1 位作者 Song-tao Li Zong-xin Xia 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第4期617-622,共6页
Brain-derived neurotrophic factor(BDNF) plays an important role in the repair of central nervous system injury,but cannot directly traverse the blood-brain barrier.Liposomes are a new type of non-viral vector,able t... Brain-derived neurotrophic factor(BDNF) plays an important role in the repair of central nervous system injury,but cannot directly traverse the blood-brain barrier.Liposomes are a new type of non-viral vector,able to carry macromolecules across the blood-brain barrier and into the brain.Here,we investigate whether BDNF could be transported across the blood-brain barrier by tail-vein injection of liposomes conjugated to transferrin(Tf) and polyethylene glycol(PEG),and carrying BDNF modified with cytomegalovirus promoter(pC MV) or glial fibrillary acidic protein promoter(p GFAP)(Tf-p CMV-BDNF-PEG and Tf-p GFAP-BDNF-PEG,respectively).Both liposomes were able to traverse the blood-brain barrier,and BDNF was mainly expressed in the cerebral cortex.BDNF expression in the cerebral cortex was higher in the Tf-p GFAP-BDNF-PEG group than in the Tf-p CMV-BDNF-PEG group.This study demonstrates the successful construction of a non-virus targeted liposome,Tf-p GFAP-BDNF-PEG,which crosses the blood-brain barrier and is distributed in the cerebral cortex.Our work provides an experimental basis for BDNF-related targeted drug delivery in the brain. 展开更多
关键词 nerve regeneration brain injury brain-derived neurotrophic factor liposomes targeting vector transfection hippocampus cortex encapsulation efficiency blood-brain barrier transferrin glial fibrillary acidic protein polyethylene glycol neural regeneration
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Impacts of Market-based Environmental Regulation on Green Total Factor Energy Efficiency in China
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作者 Ge Li Da Gao Yi Li 《China & World Economy》 2023年第3期92-114,共23页
This study employed a difference-in-differences design to assess the effect of marketbased environmental regulation on green total factor energy efficiency(GTFEE)in a quasi-natural experiment that investigated China&#... This study employed a difference-in-differences design to assess the effect of marketbased environmental regulation on green total factor energy efficiency(GTFEE)in a quasi-natural experiment that investigated China's carbon emissions trading scheme(ETS).The empirical results show that ETS had a positive effect on GTFEE.A series of robustness tests revealed that the results were robust.Potential mechanisms through which ETS can improve GTFEE include the promotion of technological innovation and the upgrading of industrial structure.The positive effects varied in different cities and diferent regions-the result was pronounced in eastern China and developed cities,but it was insignificant in central and western areas and developing cities.This study confirms the satisfactory performance of China's ETS in improving GTFEE,and this is relevant for other emerging countries. 展开更多
关键词 carbon emissions trading schemes DIFFERENCE-IN-DIFFERENCES green tota factor energy efficiency market-based environmental regulation
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Numerical Simulations of Tungsten Alloy Rods Penetration into Alumina Ceramic/Armor Steel Composite Target 被引量:3
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作者 李金柱 黄风雷 张连生 《Journal of Beijing Institute of Technology》 EI CAS 2008年第3期253-258,共6页
The Johnson-Holmquist constitutive ceramic model is re-implemented into the LS_ DYNA3D program to simulate the penetration of long rod projectile into ceramic/armor steel composite targets. The damage evolution, fract... The Johnson-Holmquist constitutive ceramic model is re-implemented into the LS_ DYNA3D program to simulate the penetration of long rod projectile into ceramic/armor steel composite targets. The damage evolution, fracture propagation, and spall damage in the ceramic/armor targets is represented during the simulation procedure and the accuracy of the penetration depth comparing between the simulating and experimental results is reliable with an error less than 8 %. The relationship between the mass efficiency factor, differential factor and ceramic tiles thickness is given out for the penetration results with/without a cover plate. 展开更多
关键词 alumina ceramic mass efficiency factor JHC model damage distribution
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The clinical study of ultrasound-guided intra-hysteromyoma injection of ethyl alcohol absolute combined with HIFU in the treatment of uterine fibroids 被引量:5
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作者 Xiaoli Zou Baixin Sun +1 位作者 Li Jia Xiaobei Liu 《Oncology and Translational Medicine》 2018年第5期203-207,共5页
Objective The aim of this study was to investigate the energy deposition in the target area of high intensity focused ultrasound (HIFU) with ultrasound-guided intra-hysteromyoma injection of ethyl alcohol absolute M... Objective The aim of this study was to investigate the energy deposition in the target area of high intensity focused ultrasound (HIFU) with ultrasound-guided intra-hysteromyoma injection of ethyl alcohol absolute Methods Eighty patients with hysteromyomas were randomly divided into two groups: group HIFU (group H) and group HIFU combined with ullrasound-guided inlra-hysteromyoma injectionn of ethyl alcohol absolute (group E + H). Patients in group E + H received an ullrasound-guided injection of absolute ethyl alcohol 1 h before HIFU treatment. The irradiation time, irradiation dose, energy efficiency factor (radiation energy required for ablation of a myoma per unit of volume), grey variation, pain score, and adverse reactions were compared between the two groups. An independent sample t-test was used with a two- tailed P-value of 〈 0.05. Results The irradiation time, irradiation dose, and energy efficiency factor were significantly lower in group E + H than those in group H (P 〈 0.05). The hysteromyomas of patients in group E+H appeared as dominantly hyperechoic masses, and those of patients in group H appeared as hyperechoic tissue (non- mass). The incidence of adverse reactions and pain score were higher in group H than those in group E + H (P 〈 0.05). Conclusion Ultrasound-guided inlra-hysteromyoma injection of ethyl alcohol absolute can enhance the energy deposition of HIFU in the uterine fibroids, improve the treatment efficiency, shorten the treatment time, reduce the treatment dose, and reduce the pain and complications for the patients. 展开更多
关键词 high-intensity focused ultrasonography (HIFU) absolute ethyl alcohol hysteromyomas uterine fibroids energy efficiency factor
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Groundwater Waves in a Coastal Fractured Aquifer of the Third Phase Qinshan Nuclear Power Engineering Field 被引量:1
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作者 周念清 唐益群 唐和平 《Journal of Shanghai Jiaotong university(Science)》 EI 2005年第4期441-445,共5页
Tidal fluctuations of Hangzhou Bay produce progressive pressure waves in adjacent field fractured aquifers, as the pressure waves propagate, groundwater levels and hydraulic gradients continuously fluctuate. The effec... Tidal fluctuations of Hangzhou Bay produce progressive pressure waves in adjacent field fractured aquifers, as the pressure waves propagate, groundwater levels and hydraulic gradients continuously fluctuate. The effect of tidal fluctuations on groundwater flow can be determined using the mean hydraulic gradient that can be calculated by comparing mean ground and surface water elevations.Tidal fluctuation is shown to affect the piezometer readings taken in a nearshore fractured aquifer around the nuclear power engineering field. Continuous monitoring of a network of seven piezometers provided relations between the tidal cycle and the piezometer readings. The relations can be expressed in times of a time and amplitude scaling factor. The time lag and the tidal efficiency factor and wavelength are calculated using these parameters. It provides significant scientific basis to prevent tide and groundwater for the nuclear power engineering construction and safety run of nuclear power station in the future. 展开更多
关键词 tidal fluctuation fractured aquifer hydraulic gradient time lag tidal efficiency factor nuclear power engineering
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Ant Colony Optimization for Task Allocation in Multi-Agent Systems 被引量:1
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作者 王鲁 王志良 +1 位作者 胡四泉 刘磊 《China Communications》 SCIE CSCD 2013年第3期125-132,共8页
Task allocation is a key issue of agent cooperation mechanism in Multi-Agent Systems. The important features of an agent system such as the latency of the network infrastructure, dynamic topology, and node heterogenei... Task allocation is a key issue of agent cooperation mechanism in Multi-Agent Systems. The important features of an agent system such as the latency of the network infrastructure, dynamic topology, and node heterogeneity impose new challenges on the task allocation in Multi-Agent environments. Based on the traditional parallel computing task allocation method and Ant Colony Optimization (ACO), a novel task allocation method named Collection Path Ant Colony Optimization (CPACO) is proposed to achieve global optimization and reduce processing time. The existing problems of ACO are analyzed; CPACO overcomes such problems by modifying the heuristic function and the update strategy in the Ant-Cycle Model and establishing a threedimensional path pheromone storage space. The experimental results show that CPACO consumed only 10.3% of the time taken by the Global Search Algorithm and exhibited better performance than the Forward Optimal Heuristic Algorithm. 展开更多
关键词 multi-agent systems task alloca- tion ant colony optimization efficiency factor
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Adsorption Behavior of Reducing End-Modified Cellulose Nanocrystals:A Kinetic Study Using Quartz Crystal Microbalance
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作者 Maud Chemin Céline Moreau +1 位作者 Bernard Cathala Ana Villares 《Journal of Renewable Materials》 SCIE EI 2020年第1期29-43,共15页
In this work,we studied the adsorption of modified cellulose nanocrystals onto solid surfaces by quartz crystal microbalance with dissipation monitoring(QCM-D).Cellulose nanocrystals obtained from tunicate(CNC)were mo... In this work,we studied the adsorption of modified cellulose nanocrystals onto solid surfaces by quartz crystal microbalance with dissipation monitoring(QCM-D).Cellulose nanocrystals obtained from tunicate(CNC)were modified at reducing end by amidation reactions.Two different functionalities were investigated:a polyamine dendrimer(CNC-NH_(2)),which interacts with gold surface by the amine groups;and a biotin moiety(CNC-Biot),which has a strong affinity for the protein streptavidin(SAV).QCM-D results revealed different adsorption behaviors between modified and unmodified CNCs.Hence,unmodified CNCs covered almost all the surface forming a rigid and flat layer whereas reducing end modified CNCs remained rather upright forming a hydrated and viscoelastic layer with lower surface coverage.The analysis of adsorption kinetics allowed the calculation of an apparent collision rate factor,which resulted 10-fold higher for unmodified CNCs compared to reducing end modified CNCs,therefore,demonstrating the different adsorption behavior. 展开更多
关键词 Cellulose nanocrystals AMIDATION reducing-end modification Voight model collision rate efficiency factor rate constant
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Industrial Green Spatial Pattern Evolution of Yangtze River Economic Belt in China 被引量:3
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作者 LI Lin LIU Ying 《Chinese Geographical Science》 SCIE CSCD 2017年第4期660-672,共13页
We use the directional slacks-based measure of efficiency and inverse distance weighting method to analyze the spatial pattern evolution of the industrial green total factor productivity of 108 cities in the Yangtze R... We use the directional slacks-based measure of efficiency and inverse distance weighting method to analyze the spatial pattern evolution of the industrial green total factor productivity of 108 cities in the Yangtze River Economic Belt in 2003–2013.Results show that both the subprime mortgage crisis and ‘the new normal' had significant negative effects on productivity growth,leading to the different spatial patterns between 2003–2008 and 2009–2013.Before 2008,green poles had gathered around some capital cities and formed a tripartite pattern,which was a typical core-periphery pattern.Due to a combination of the polarization and the diffusion effects,capital cities became the growth poles and ‘core' regions,while surrounding areas became the ‘periphery'.This was mainly caused by the innate advantage of capital cities and ‘the rise of central China' strategy.After 2008,the tripartite pattern changed to a multi-poles pattern where green poles continuously and densely spread in the midstream and downstream areas.This is due to the regional difference in the leading effect of green poles.The leading effect of green poles in midstream and downstream areas has changed from polarization to diffusion,while the polarization effect still leads in the upstream area. 展开更多
关键词 Yangtze River Economic Belt industrial green total factor productivity directional slacks-based measure of efficiency inverse distance weighting spatial pattern evolution
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Regional characteristics of industrial energy efficiency in China: application of stochastic frontier analysis method
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作者 Tao HUANG Akio ONISHI +2 位作者 Feng SHI Masafumi MORISUGI Mjo Lwin CHERRY 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2015年第3期506-521,共16页
This paper analyzed regional industrial energy efficiency in China with Total-Factor Energy Efficiency (TFEE). The East region has the best energy efficiency and the Central and the West regions stand as the second ... This paper analyzed regional industrial energy efficiency in China with Total-Factor Energy Efficiency (TFEE). The East region has the best energy efficiency and the Central and the West regions stand as the second and the third respectively. However, it is found that industrial energy efficiency of all regions increased from 1998 to 2006. This result is consistent with level of economic development of every region. The industries of all provinces in China are not yet at the frontier efficiency position, therefore, to the frontier as target, their technol- ogy levels and production processes should be adjusted accordingly. Compared with the conventional energy efficiency, the inverse of energy intensity, which is defined as the ratio of actual output to energy input, is regarded as Single-Factor Energy Efficiency (SFEE) index. Although TFEE ranks are not changed for each region, they are different for each province. The comparative result also shows that the substitution among inputs (labor, capital stock, and energy) to produce the output is significant. The SFEE scores could be over-estimated if energy is taken as the single input in the production. Finally, we identified determining factors affecting industrial energy efficiency using Tobit model. The results indicate that an increase of per capita Gross Domestic Product (GDP), the percentage of output value of industry invested by Hong Kong, Macao, Taiwan and abroad, energy price and investment of scientific and technological activities for industry could be possible contributors and drivers to the industrial energy efficiency. However, increasing of heavy industry will lead to worse industrial energy efficiency. 展开更多
关键词 industrial energy efficiency stochastic frontieranalysis total-factor energy efficiency single factor energy efficiency
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Energy Management Strategy for Hybrid Electric Vehicle Based on System Efficiency and Battery Life Optimization
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作者 YANG Yang SU Ling +2 位作者 QIN Datong GONG Hui ZENG Jianfeng 《Wuhan University Journal of Natural Sciences》 CAS 2014年第3期269-276,共8页
A novel method to calculate fuel-electric conversion factor for full hybrid electric vehicle(HEV)equipped with continuously variable transmission(CVT)is proposed.Based on consideration of the efficiency of pivotal... A novel method to calculate fuel-electric conversion factor for full hybrid electric vehicle(HEV)equipped with continuously variable transmission(CVT)is proposed.Based on consideration of the efficiency of pivotal components,electric motor,system efficiency optimization models are developed.According to the target of instantaneous optimization of system efficiency,operating ranges of each mode of power-train are determined,and the corresponding energy management strategies are established.The simulation results demonstrate that the energy management strategy proposed can substantially improve the vehicle fuel economy,and keep battery state of charge(SOC)change in a reasonable variation range. 展开更多
关键词 hybrid electric vehicle energy management strategy efficiency optimization battery state of charge fuel-electric conversion factor
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RE-USE OF SPENT CATALYST FROM OIL-CRACKING REFINERIES AS SUPPLEMENTARY CEMENTING MATERIAL 被引量:3
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作者 S. K. Antiohos E. Chouliara S. Tsimas 《China Particuology》 SCIE EI CAS CSCD 2006年第2期73-76,共4页
Advanced technological achievements and the continuous growth of economy have made the disposal, recycle and reuse of industrial by-products a severe challenge. The cement industry is considered one of the key sectors... Advanced technological achievements and the continuous growth of economy have made the disposal, recycle and reuse of industrial by-products a severe challenge. The cement industry is considered one of the key sectors in this effort in successfully (in terms of not extenuating but improving some of the properties of the final product) absorbing large quantities of solid wastes, either as aggregates or as secondary cementitious materials. This not only contributes to the creation of an energy and CO2-emission depository (as commonly used raw materials are spared), but also simultaneously alleviates the acute environmental burden caused by the irresponsible disposal of such by-products. In this study, the possibility of reusing spent fluid catalytic-cracking catalyst (FCC) as a supplementary cementing material (SCM) was examined. A series of tests were conducted, initially aiming at characterizing the material and thereafter evaluating its pozzolanic activity and its effect on the mechanical properties of blended cements. Major findings in this investigation revealed that the use of FCC as a mineral admixture in cement is feasible, strengthening the belief that siliceous glassy residues should represent a steady supply for the construction sector. 展开更多
关键词 spent catalyst supplementary cementing material reactive silica efficiency factor blended cement
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Performance assessment of Alccofine with silica fume,fly ash and slag for development of high strength mortar
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作者 Shivang D.JAYSWAL Mahesh MUNGULE 《Frontiers of Structural and Civil Engineering》 SCIE EI CSCD 2022年第5期576-588,共13页
Previous studies on concrete have identified silica fume(SF)as the most effective supplementary material,whereas fly ash(FA)and slag have been identified as economical materials with long term strength potential.Devel... Previous studies on concrete have identified silica fume(SF)as the most effective supplementary material,whereas fly ash(FA)and slag have been identified as economical materials with long term strength potential.Development of blended cement mortar referred to as blended mortar(BM)requires similar assessment.The present study explores the application of Alccofine(AL)as supplementary material and compares its performance with conventional materials namely SF,FA and ground granulated blast furnace slag(GGBS).The mortar specimens with binder to fine-aggregates(b/f)ratio of 1:2 are prepared at water to binder(w/b)ratios of 0.4 and 0.35.The strength values and stress-strain curve for control and BM specimens are obtained at 7,28,56,and 90 d curing periods.The assessment based on strength activity index,k-value method and strength estimation model confirms that AL,despite lower pozzolanic activity,contributes to strength gain,due to reduced dilution effect.Assessment of stress-strain curves suggests that the effect of w/b ratio is more dominant on the elastic modulus of BM specimens than on control specimens.The observations from the study identify enhanced strength gain,improved elastic modulus and higher energy absorption as key contributions of AL making it a potential supplementary material. 展开更多
关键词 Alccofine high strength mortar efficiency factor dilution effect
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