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Efficient desorption and reuse of collector from the flotation concentrate:A case study of scheelite
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作者 Liming Tao Jianjun Wang +6 位作者 Dejin Liao Wenkai Jia Zihan Zhao Wenfang Che Zhongxu Qi Wei Sun Zhiyong Gao 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第11期2435-2444,共10页
Flotation is the most common method to obtain concentrate through the selective adsorption of collectors on target minerals to make them hydrophobic and floatable.In the hydrometallurgy of concentrate,collectors adsor... Flotation is the most common method to obtain concentrate through the selective adsorption of collectors on target minerals to make them hydrophobic and floatable.In the hydrometallurgy of concentrate,collectors adsorbed on concentrate can damage ion-exchange resin and increase the chemical oxygen demand(COD)value of wastewater.In this work,we proposed a new scheme,i.e.,desorbing the collectors from concentrate in ore dressing plant and reusing them in flotation flowsheet.Lead nitrate and benzohydroxamic acid(Pb-BHA)complex is a common collector in scheelite flotation.In this study,different physical(stirring or ultrasonic waves)and chemical(strong acid or alkali environment)methods for facilitating the desorption of Pb-BHA collector from scheelite concentrate were explored.Single-mineral desorption tests showed that under the condition of pulp pH 13 and ultrasonic treatment for 15 min,the highest desorption rates of Pb and BHA from the scheelite concentrate were 90.48%and 63.75%,respectively.Run-of-mine ore flotation tests revealed that the reuse of desorbed Pb and BHA reduced the collector dosage by 30%for BHA and 25%for Pb.The strong alkali environment broke the chemical bonds between Pb and BHA.The cavitation effect of ultrasonic waves effectively reduced the interaction intensity between Pb-BHA collector and scheelite surfaces.This method combining ultrasonic waves and strong alkali environment can effectively desorb the collectors from concentrate and provide“clean”scheelite concentrate for metallurgic plants;the reuse of desorbed collector in flotation flowsheet can reduce reagent cost for ore dressing plants. 展开更多
关键词 scheelite concentrate collector DESORPTION REUSE FLOTATION
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A Study on the Performances of Solar Air Collectors Having a Hemispherical Dimple on the Absorber Plate
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作者 Shuilian Li Fan Zeng Xinli Wei 《Fluid Dynamics & Materials Processing》 EI 2024年第5期939-955,共17页
In order to increase the efficiency of solar air collectors,a new variant with a protrusion is proposed in this study,and its performances are analyzed from two points of view,namely,in terms of optics and thermodynam... In order to increase the efficiency of solar air collectors,a new variant with a protrusion is proposed in this study,and its performances are analyzed from two points of view,namely,in terms of optics and thermodynamics aspects.By comparing and analyzing the light paths of the protrusion and the dimple,it can be concluded that when sunlight shines on the dimple,it is reflected and absorbed multiple times,whereas for the sunlight shining on the protrusion,there is no secondary reflection or absorption of light.When the lighting area and the properties of the surfaces are the same,the absorption rate of the dimple is 10.3 percentage points higher than that of the protrusion.In the range of Reynolds number from 3000 to 11000,numerical simulations about the effects of the relative height(e/Dh=0.033–0.1)and relative spacing(p/e=4.5–8.5)of protrusions on air heat transfer and flow resistance show that,in terms of comprehensive evaluation coefficient(PF),the best relative height is 0.085,when the relative spacing is 5.A correlation of Nu and f with Re,e/Dh and p/e is obtained by linear regression of the results,in order to provide a useful reference for the design and optimization of this kind of solar air collector. 展开更多
关键词 Heat transfer hemispherical protrusion DIMPLE solar air collector CORRELATION
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Revisiting aluminum current collector in lithium-ion batteries:Corrosion and countermeasures
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作者 Shanglin Yang Jinyan Zhong +1 位作者 Songmei Li Bin Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期610-634,I0014,共26页
With the large-scale service of lithium-ion batteries(LIBs),their failures have attracted significant attentions.While the decay of active materials is the primary cause for LIB failures,the degradation of auxiliary m... With the large-scale service of lithium-ion batteries(LIBs),their failures have attracted significant attentions.While the decay of active materials is the primary cause for LIB failures,the degradation of auxiliary materials,such as current collector corrosion,should not be disregarded.Therefore,it is necessary to conduct a comprehensive review in this field.In this review,from the perspectives of electrochemistry and materials,we systematically summarize the corrosion behavior of aluminum cathode current collector and propose corresponding countermeasures.Firstly,the corrosion type is clarified based on the properties of passivation layers in different organic electrolyte components.Furthermore,a thoroughgoing analysis is presented to examine the impact of various factors on aluminum corrosion,including lithium salts,organic solvents,water impurities,and operating conditions.Subsequently,strategies for electrolyte and protection layer employed to suppress corrosion are discussed in detail.Lastly and most importantly,we provide insights and recommendations to prevent corrosion of current collectors,facilitate the development of advanced current collectors and the implementation of next-generation high-voltage stable LIBs. 展开更多
关键词 Lithium-ion battery Aluminum current collector CORROSION Electrochemical performance ELECTROLYTE Protective layer
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Heat Transfer Enhancement of the Absorber Tube in a Parabolic Trough Solar Collector through the Insertion of Novel Cylindrical Turbulators
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作者 Yasser Jebbar Fadhil Fluiful Wisam Khudhayer 《Fluid Dynamics & Materials Processing》 EI 2024年第6期1279-1297,共19页
This study includes an experimental and numerical analysis of the performances of a parabolic trough collector(PTC)with and without cylindrical turbulators.The PTC is designed with dimensions of 2.00 m in length and 1... This study includes an experimental and numerical analysis of the performances of a parabolic trough collector(PTC)with and without cylindrical turbulators.The PTC is designed with dimensions of 2.00 m in length and 1.00 m in width.The related reflector is made of lined sheets of aluminum,and the tubes are made of stainless steel used for the absorption of heat.They have an outer diameter of 0.051 m and a wall thickness of 0.002 m.Water,used as a heat transfer fluid(HTF),flows through the absorber tube at a mass flow rate of 0.7 kg/s.The dimensions of cylindrical turbulators are 0.04 m in length and 0.047 m in diameter.Simulations are performed using the ANSYS Fluent 2020 R2 software.The PTC performance is evaluated by comparing the experimental and numerical outcomes,namely,the outlet temperature,useful heat,and thermal efficiency for a modified tube(MT)(tube with novel cylindrical turbulators)and a plain tube(PT)(tube without novel cylindrical turbulators).According to the results,the experimental outlet temperatures recorded 63.2°C and 50.5°C for the MT and PT,respectively.The heat gain reaches 1137.5 Win the MT and 685.8 Win the PT.Compared to the PT collector,the PTC exhibited a(1.64 times)higher efficiency. 展开更多
关键词 Parabolic trough collector turbulators absorber tube ANSYS thermal efficiency
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Investigative Review of Design Techniques of Parabolic Trough Solar Collectors
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作者 Roba Tarek AbdelFatah Irene S.Fahim Mohamed Mahran Kasem 《Frontiers in Heat and Mass Transfer》 EI 2024年第1期317-339,共23页
Parabolic trough solar collectors(PTCs)are among the most cost-efficient solar thermal technologies.They have several applications,such as feed heaters,boilers,steam generators,and electricity generators.A PTC is a co... Parabolic trough solar collectors(PTCs)are among the most cost-efficient solar thermal technologies.They have several applications,such as feed heaters,boilers,steam generators,and electricity generators.A PTC is a concentrated solar power system that uses parabolic reflectors to focus sunlight onto a tube filled with heattransfer fluid.PTCs performance can be investigated using optical and thermal mathematical models.These models calculate the amount of energy entering the receiver,the amount of usable collected energy,and the amount of heat loss due to convection and radiation.There are several methods and configurations that have been developed so far;however,it is usually difficult for a designer to choose the appropriate method or configuration for his application.The present work investigates different PTC configurations and methods of solution,compares their efficiency and accuracy,summarizes their key behaviors and trends,and improves the available methods by maximizing the positives and minimizing the negatives among them.We investigated three methods and seven configurations.The findings suggest that optimizing the collector structure,tracking system,and reflector can lead to high PTC performance and reduced capital costs.After investigating and comparing the recent mathematical models,the study identified a clear deficiency in estimating the output temperature.Three PTC’s solution methods are investigated,and a novel method is developed to give more accurate estimations of the output temperature. 展开更多
关键词 Parabolic trough collectors solar collector PTC mathematical models
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Current collectors’ effects on the electrochemical performance of LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2) suspension electrodes for lithium slurry battery
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作者 Linshan Peng Yufei Ren +3 位作者 Zhaoqiang Yin Zhitong Wang Xiangkun Wu Lan Zhang 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第8期1306-1313,共8页
Take after the advantages of lithium-ion battery (LIB) and redox flow battery (RFB), semi-solid flow battery (SSFB) is a promising electrochemical energy storage device in renewable energy utilization. The flowable sl... Take after the advantages of lithium-ion battery (LIB) and redox flow battery (RFB), semi-solid flow battery (SSFB) is a promising electrochemical energy storage device in renewable energy utilization. The flowable slurry electrode realizes decouple of energy and power density, while it also brings about new challenge to SSFBs, electron transport between active material and the out circuit. In this consideration, three types of current collectors (CCs) are applied to study the resistance and electrochemical performances of slurry cathodes within pouch cells for the first time. It proves that the electronic resistance (Re) between slurry electrode and the CC plays a decisive role in SSFB operation, and it is so large when Al foil is adopted that the cell cannot even work. Contact angle between Ketjen black (KB) slurry without active material (AM) and the CC is a preliminarily sign for the Re, the smaller the angle, the lower the resistance, and the better electrochemical performance of the cell. 展开更多
关键词 Semi-solid flow battery Slurry electrode Current collector Electronic resistance Carbon coated Al
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Laser-Constructing 3D Copper Current Collector with Crystalline Orientation Selectivity for Stable Lithium Metal Batteries
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作者 Hui Li Gang Wang +3 位作者 Jin Hu Jun Li Jiaxu Huang Shaolin Xu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第6期129-139,共11页
The practical application of lithium(Li)metal anodes in high-capacity batteries is impeded by the formation of hazardous Li dendrites.To address this challenge,this research presents a novel methodology that combines ... The practical application of lithium(Li)metal anodes in high-capacity batteries is impeded by the formation of hazardous Li dendrites.To address this challenge,this research presents a novel methodology that combines laser ablation and heat treatment to precisely induce controlled grain growth within laser-structured grooves on copper(Cu)current collectors.Specifically,this approach enhances the prevalence of Cu(100)facets within the grooves,effectively lowering the overpotential for Li nucleation and promoting preferential Li deposition.Unlike approaches that modify the entire surface of collectors,our work focuses on selectively enhancing lithiophilicity within the grooves to mitigate the formation of Li dendrites and exhibit exceptional performance metrics.The half-cell with these collectors maintains a remarkable Coulombic efficiency of 97.42%over 350 cycles at 1 mA cm^(−2).The symmetric cell can cycle stably for 1600 h at 0.5 mA cm^(−2).Furthermore,when integrated with LiFePO4 cathodes,the full-cell configuration demonstrates outstanding capacity retention of 92.39%after 400 cycles at a 1C discharge rate.This study introduces a novel technique for fabricating selective lithiophilic three-dimensional(3D)Cu current collectors,thereby enhancing the performance of Li metal batteries.The insights gained from this approach hold promise for enhancing the performance of all laser-processed 3D Cu current collectors by enabling precise lithiophilic modifications within complex structures. 展开更多
关键词 copper current collector heat treatment laser processing lithium metal battery selective crystalline orientation
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The Effects of the Geometry of a Current Collector with an Equal Open Ratio on Output Power of a Direct Methanol Fuel Cell
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作者 Yingli Zhu Jiachi Xie +2 位作者 Mingwei Zhu Jun Zhang Miaomiao Li 《Energy Engineering》 EI 2024年第5期1161-1172,共12页
The open ratio of a current collector has a great impact on direct methanol fuel cell(DMFC)performance.Although a number of studies have investigated the influence of the open ratio of DMFC current collectors,far too ... The open ratio of a current collector has a great impact on direct methanol fuel cell(DMFC)performance.Although a number of studies have investigated the influence of the open ratio of DMFC current collectors,far too little attention has been given to how geometry(including the shape and feature size of the flow field)affects a current collector with an equal open ratio.In this paper,perforated and parallel current collectors with an equal open ratio of 50%and different feature sizes are designed,and the corresponding experimental results are shown to explain the geometry effects on the output power of the DMFC.The results indicate that the optimal feature sizes are between 2 and 2.5 mm for both perforated and parallel flow field in the current collectors with an equal open ratio of 50%.This means that for passive methanol fuel cells,to achieve the highest output power,the optimal feature size of the flow field in both anode and cathode current collectors is between 2 and 2.5 mm under the operating mode of this experiment.The effects of rib and channel position are also investigated,and the results indicate that the optimum pattern depends on the feature sizes of the flow field. 展开更多
关键词 Direct methanol fuel cell GEOMETRY open ratio current collector POSITION
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Thermodynamic Analysis and Optimization of Flat Plate Solar Collector Using TiO_(2)/Water Nanofluid
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作者 Firas F.Qader Falah Z.Mohammed Barhm Mohamad 《Journal of Harbin Institute of Technology(New Series)》 CAS 2024年第4期61-73,共13页
To research solar energy's efficiency and environmental benefits,the thermal efficiency,exergy,and entropy of solar collectors were calculated.The experiment involved two glass-topped collectors,fluid transfer tub... To research solar energy's efficiency and environmental benefits,the thermal efficiency,exergy,and entropy of solar collectors were calculated.The experiment involved two glass-topped collectors,fluid transfer tubes,and aluminum heat-absorbing plates.Glass wool insulation minimized heat loss.A 0.5% TiO_(2)/Water nanofluid was created using a mechanical and ultrasonic stirrer.Results showed that solar radiation increased thermal efficiency until midday,reaching 48.48% for water and 51.23% for the nanofluid.With increasing mass flow rates from 0.0045 kg/s to 0.02 kg/s,thermal efficiency improved from 16.26% to 47.37% for water and from 20.65% to 48.76% for the nanofluid.Filtered water provided 380 W and 395 W of energy in March and April,while the nanofluid increased it to 395 W and 415 W during these months.Mass flow generated energy,and the Reynolds number raised entropy.The noon exergy efficiency for nanofluids was 50%-55%,compared to 30% for water.At noon,the broken exergy measured 877.53 W for the nanofluid and 880.12 W for water.In Kirkuk,Iraq,the 0.5% TiO_(2)/Water nanofluid outperformed water in solar collectors. 展开更多
关键词 ENERGY EXERGY entropy generation NANOFLUID flat plate solar collector
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An Experimental and Numerical Thermal Flow Analysis in a Solar Air Collector with Different Delta Wing Height Ratios
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作者 Ghobad Shafiei Sabet Ali Sari +3 位作者 Ahmad Fakhari Nasrin Afsarimanesh Dominic Organ Seyed Mehran Hoseini 《Frontiers in Heat and Mass Transfer》 EI 2024年第2期491-509,共19页
This study conducts both numerical and empirical assessments of thermal transfer and fluid flow characteristics in a Solar Air Collector(SAC)using a Delta Wing Vortex Generator(DWVG),and the effects of different heigh... This study conducts both numerical and empirical assessments of thermal transfer and fluid flow characteristics in a Solar Air Collector(SAC)using a Delta Wing Vortex Generator(DWVG),and the effects of different height ratios(Rh=0.6,0.8,1,1.2 and 1.4)in delta wing vortex generators,which were not considered in the earlier studies,are investigated.Energy and exergy analyses are performed to gain maximum efficiency.The Reynolds number based on the outlet velocity and hydraulic diameter falls between 4400 and 22000,corresponding to the volume flow rate of 5.21–26.07 m^(3)/h.It is observed that the delta wing vortex generators with a higher height ratio yield maximum heat transfer enhancement and overall enhancement ratio.The empirical and numerical findings demonstrate that the exergy and thermal efficiencies decline in a specific range.TheNusselt number,pressure drop,energy,and exergy efficiencies enhance with rising Reynolds number,although the friction coefficient diminishes.The maximum heat transfer enhancement is 57%.According to the evaluation of exergy efficiency,the greatest efficiency of 31.2%is obtained at Rh=1.4 and Reynolds number 22000. 展开更多
关键词 Vortex generators heat transfer augmentation numerical simulation solar air collector empirical height ratio
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Experimental Study of Temperature and Humidity Variations in an Incubator Fitted with a Flat-Plate Collector
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作者 Germain Wende Pouiré Ouedraogo Boureima Dianda +2 位作者 Boureima Kabore Carole Flaviane Teguiwendé Sawadogo Sié Kam 《Smart Grid and Renewable Energy》 2024年第11期267-275,共9页
In Burkina Faso, where livestock farming is widely practiced, particularly in rural areas without access to electricity, solar energy offers a viable alternative due to the country’s abundant sunshine. To support pou... In Burkina Faso, where livestock farming is widely practiced, particularly in rural areas without access to electricity, solar energy offers a viable alternative due to the country’s abundant sunshine. To support poultry farmers in increasing their production, we developed a solar-powered incubator equipped with a flat-plate collector, requiring no grid electricity. This is a new approach that we want to experiment with because the incubators on the global market operate either with the electricity grid, photovoltaic, gas or oil and not a solar thermal concentrator. This solar concentrator represents the heat source of the device during the day. We plan to look for rocks with high thermal inertia in order to heat them during the day using another flat solar concentrator and then introduce them into the incubator at night to continue the incubation process. In 2022, we conducted a simulation to study temperature variation inside the incubator. In this work, we built a prototype to experimentally evaluate key hydrothermal properties such as air temperature and humidity. Furthermore, we will not introduce rocks into the incubator overnight but will let the system run overnight to see how the hygrothermal properties vary. The findings revealed temperature fluctuations from 25˚C to 65˚C, instead of the desired 36˚C to 38˚C, and humidity levels ranging from 15% to 57%, instead of the target 55% to 75%. Solutions have been proposed to enhance the system’s performance. 展开更多
关键词 Solar Incubator Flat-Plate collector Hygrothermal Properties
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Improving Heat Transfer in Parabolic Trough Solar Collectors by Magnetic Nanofluids
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作者 Ritesh Singh Abhishek Gupta +2 位作者 Akshoy Ranjan Paul Bireswar Paul Suvash C.Saha 《Energy Engineering》 EI 2024年第4期835-848,共14页
A parabolic trough solar collector(PTSC)converts solar radiation into thermal energy.However,low thermal efficiency of PTSC poses a hindrance to the deployment of solar thermal power plants.Thermal performance of PTSC... A parabolic trough solar collector(PTSC)converts solar radiation into thermal energy.However,low thermal efficiency of PTSC poses a hindrance to the deployment of solar thermal power plants.Thermal performance of PTSC is enhanced in this study by incorporating magnetic nanoparticles into the working fluid.The circular receiver pipe,with dimensions of 66 mm diameter,2 mm thickness,and 24 m length,is exposed to uniform temperature and velocity conditions.The working fluid,Therminol-66,is supplemented with Fe3O4 magnetic nanoparticles at concentrations ranging from 1%to 4%.The findings demonstrate that the inclusion of nanoparticles increases the convective heat transfer coefficient(HTC)of the PTSC,with higher nanoparticle volume fractions leading to greater heat transfer but increased pressure drop.The thermal enhancement factor(TEF)of the PTSC is positively affected by the volume fraction of nanoparticles,both with and without a magnetic field.Notably,the scenario with a 4%nanoparticle volume fraction and a magnetic field strength of 250 G exhibits the highest TEF,indicating superior thermal performance.These findings offer potential avenues for improving the efficiency of PTSCs in solar thermal plants by introducing magnetic nanoparticles into the working fluid. 展开更多
关键词 Parabolic trough solar collector(PTSC) magnetic nanofluid(MNF) heat transfer convective heat transfer coefficient(HTC) thermal enhancement factor(TEF)
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Performance of a Combined Energy System Consisting of Solar Collector, Biogas Dry Reforming and Solid Oxide Fuel Cell: An Indian Case Study
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作者 Akira Nishimura Ryotaro Sato +1 位作者 Ryota Nakajima Eric Hu 《Smart Grid and Renewable Energy》 2024年第10期217-247,共31页
An energy production system consisting of a solar collector, biogas dry reforming reactor and solid oxide fuel cell (SOFC) was assumed to be installed in Kolkata, India. This study aims to understand the impact of cli... An energy production system consisting of a solar collector, biogas dry reforming reactor and solid oxide fuel cell (SOFC) was assumed to be installed in Kolkata, India. This study aims to understand the impact of climate conditions on the performance of solar collectors with different lengths of parabolic trough solar collector (dx) and mass flow rate of heat transfer fluid (m). In addition, this study has evaluated the amount of H2 produced by biogas dry reforming (GH2), the amount of power generated by SOFC (PSOFC) and the maximum number of possible households (N) whose electricity demand could be met by the energy system proposed, considering the performance of solar collector with the different dx and m. As a result, the optimum dx was found to be 4 m. This study revealed that the temperature of heat transfer fluid (Tfb) decreased with the increase in m. Tfb in March, April and May was higher than that in other months, while Tfb from June to December was the lowest. GH2, PSOFC and N in March, April and May were higher than those in other months, irrespective of m. The optimum m was 0.030 kg/s. 展开更多
关键词 Solar collector Temperature of Simulated Biogas Case Study of Installation in India H2 Production by Dry Reforming Power Generated by SOFC
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Flotation of low-grade bauxite using organosilicon cationic collector and starch depressant 被引量:7
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作者 余新阳 王浩林 +2 位作者 王强强 冯博 钟宏 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第4期1112-1117,共6页
The flotation of diaspore and three kinds of silicate minerals, including kaolinite, illite and pyrophyllite, using an organosilicon cationic surfactant (TAS101) as collector and starch as depressant was investigated.... The flotation of diaspore and three kinds of silicate minerals, including kaolinite, illite and pyrophyllite, using an organosilicon cationic surfactant (TAS101) as collector and starch as depressant was investigated. The results show that both diaspore and aluminosilicate minerals float readily with organosilicon cationic collector TAS101 at pH values of 4 to 10. Starch has a strong depression effect for diaspore in the alkaline pH region but has little influence on the flotation of aluminosilicate minerals. It is possible to separate diaspore from aluminosilicate minerals using the organosilicon cationic collector and starch depressant. Further studies of bauxite ore flotation were also conducted, and the reverse flotation separation process was adopted. The concentrates with the mass ratio of Al2O3 to SiO2 of 9.58 and Al2O3 recovery of 83.34% are obtained from natural bauxite ore with the mass ratio of Al2O3 to SiO2 of 6.1 at pH value of 11 using the organosilicon cationic collector and starch depressant. 展开更多
关键词 BAUXITE reverse flotation organosilicon cationic collector starch depressant
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Separation behavior and mechanism of hematite and collophane in the presence of collector RFP-138 被引量:1
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作者 余侃萍 余永富 许向阳 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第2期501-507,共7页
The reverse flotation separation performance and mechanism of hematite and cellophane in the presence of RFP-138, a newly synthesized dephosphorization collector, were studied. Reverse flotation tests on monominerals ... The reverse flotation separation performance and mechanism of hematite and cellophane in the presence of RFP-138, a newly synthesized dephosphorization collector, were studied. Reverse flotation tests on monominerals and artificially mixed minerals of hematite and collophanite show that, this anionic collector performs excellently in reducing the phosphorus content in hematite. It can decrease the content of P in artificially mixed minerals from 1.05% to 0.12% and achieve the TFe recovery rate of 91.30%. The chemical behavior of solution and infrared spectra of RFP-138 were investigated to explore the selective collecting mechanism of RFP-138 to these two minerals. 展开更多
关键词 HEMATITE collophane reverse flotation separation DEPHOSPHORIZATION dephosphorization collector
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溶液环境对两种菱镁矿阴离子捕收剂浮选泡沫性能的影响
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作者 徐长明 何东升 +3 位作者 唐远 叶利峰 李智力 付艳红 《工程科学学报》 EI 北大核心 2025年第1期25-32,共8页
浮选体系中浮选泡沫各项性能直接影响其与矿物颗粒间的相互作用.采用DFA 100动态泡沫分析仪,研究了不同pH值和Mg^(2+)环境下磷酸酯盐捕收剂的起泡性能、泡沫稳定性以及泡沫结构等的性能差异,并与传统油酸盐捕收剂进行了对比分析.结果表... 浮选体系中浮选泡沫各项性能直接影响其与矿物颗粒间的相互作用.采用DFA 100动态泡沫分析仪,研究了不同pH值和Mg^(2+)环境下磷酸酯盐捕收剂的起泡性能、泡沫稳定性以及泡沫结构等的性能差异,并与传统油酸盐捕收剂进行了对比分析.结果表明,同为菱镁矿捕收剂,十六烷基磷酸酯钾(CP)捕收剂相较于传统油酸钠(NaOl)捕收剂,在pH值和Mg^(2+)浓度变化时的泡沫适应性更强,且在菱镁矿浮选中显示出更大的优势.具体来说,在相同质量浓度条件下,CP捕收剂溶液表面张力变化相对缓慢,且在所研究pH值和Mg^(2+)浓度范围内均显示相对更适宜的起泡能力和泡沫稳定性,泡沫结构也更稳定.单矿物浮选试验结果表明,菱镁矿上浮率与溶液环境对两种捕收剂泡沫性能的影响结果具有一致性.在pH值小于6.0或Mg^(2+)质量浓度超过30 mg·L^(-1)时,传统NaOl体系中菱镁矿上浮困难,浮选泡沫性能差,而CP体系中菱镁矿上浮率均保持在60%以上.本研究为磷酸酯类捕收剂在菱镁矿浮选中的应用提供了理论依据和实践指导. 展开更多
关键词 浮选 泡沫性能 溶液环境 磷酸酯捕收剂 菱镁矿
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Locally Enhanced Flow and Electric Fields Through a Tip Effect for Efficient Flow‑Electrode Capacitive Deionization
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作者 Ziquan Wang Xiangfeng Chen +5 位作者 Yuan Zhang Jie Ma Zhiqun Lin Amor Abdelkader Maria‑Magdalena Titirici Libo Deng 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期1-17,共17页
Low-electrode capacitive deionization(FCDI)is an emerging desalination technology with great potential for removal and/or recycling ions from a range of waters.However,it still suffers from inefficient charge transfer... Low-electrode capacitive deionization(FCDI)is an emerging desalination technology with great potential for removal and/or recycling ions from a range of waters.However,it still suffers from inefficient charge transfer and ion transport kinetics due to weak turbulence and low electric intensity in flow electrodes,both restricted by the current collectors.Herein,a new tip-array current collector(designated as T-CC)was developed to replace the conventional planar current collectors,which intensifies both the charge transfer and ion transport significantly.The effects of tip arrays on flow and electric fields were studied by both computational simulations and electrochemical impedance spectroscopy,which revealed the reduction of ion transport barrier,charge transport barrier and internal resistance.With the voltage increased from 1.0 to 1.5 and 2.0 V,the T-CC-based FCDI system(T-FCDI)exhibited average salt removal rates(ASRR)of 0.18,0.50,and 0.89μmol cm^(-2) min^(-1),respectively,which are 1.82,2.65,and 2.48 folds higher than that of the conventional serpentine current collectors,and 1.48,1.67,and 1.49 folds higher than that of the planar current collectors.Meanwhile,with the solid content in flow electrodes increased from 1 to 5 wt%,the ASRR for T-FCDI increased from 0.29 to 0.50μmol cm^(-2) min^(-1),which are 1.70 and 1.67 folds higher than that of the planar current collectors.Additionally,a salt removal efficiency of 99.89%was achieved with T-FCDI and the charge efficiency remained above 95%after 24 h of operation,thus showing its superior long-term stability. 展开更多
关键词 Flow-electrode Capacitive deionization Current collector Tip effect DESALINATION
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Experiment and numerical simulation on flow and heat transfer in all-glass evacuated tube solar collectors
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作者 张涛 韩吉田 +2 位作者 陈常念 孔令健 刘洋 《Journal of Southeast University(English Edition)》 EI CAS 2016年第4期489-495,共7页
The experimental study of natural convection in allglass evacuated tube solar collectors is performed through the experimental platform of the solar-assisted fuel cell system.The experimental facility includes solar c... The experimental study of natural convection in allglass evacuated tube solar collectors is performed through the experimental platform of the solar-assisted fuel cell system.The experimental facility includes solar collectors with different length and diameter tubes, different coating materials, and with / without guide plates, respectively. Threedimensional mathematical models on natural and forced convections in the solar collectors are established and the experimental data is validated by field synergy and entransy principles. The results of natural convection show that the water temperature increases and thermal efficiency decreases gradually with the evacuated tube length. The thermal efficiency increases when absorption rates increase from 0. 95 to 1. 0 and emission rates decrease from 0. 16 to 0. 06. The thermal efficiency of solar collectors is increased after being equipped with the guide plate, which is attributed to the disappearance of the mixed flowand the enhancement of the heat transfer at the bottom of the evacuated tube. The results of forced convertion indicate that the Reynolds, Nusselt and entransy increments of the horizontal double collectors are higher than those of the vertical single collector while the entransy dissipation is lower than that of the vertical single collector. It is concluded that the solar collectors with guide plates are suitable for natural convection while the double horizontal collectors are suitable for forced convection in the thermal field of solar-assisted fuel cell systems with lowand medium temperatures. 展开更多
关键词 all-glass evacuated tube solar collectors the solar-assisted fuel cells field synergy principle entransy dissipation
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综采工作面超前支护负压喷雾集尘器除尘效果分析
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作者 戎华峰 《煤矿现代化》 2025年第1期123-128,共6页
为减少超前支护粉尘,基于计算流体力学(CFD)离散粒子模型对集尘器作用下的粉尘扩散规律的数值模拟结果,结合实验测量和现场试验,研制了一种针对综采环境下超前支护粉尘源的负压喷雾集尘器。模拟结果表明:液压支架在距离液压支架迎风面0~... 为减少超前支护粉尘,基于计算流体力学(CFD)离散粒子模型对集尘器作用下的粉尘扩散规律的数值模拟结果,结合实验测量和现场试验,研制了一种针对综采环境下超前支护粉尘源的负压喷雾集尘器。模拟结果表明:液压支架在距离液压支架迎风面0~9 m处的人行道附近形成了浓度高达1000 mg/m^(3)的高浓度粉尘带,并逐渐扩散到0~36 m处;采用负压喷雾除尘器后,液压支架背风面粉尘带浓度降至300 mg/m^(3)以下,扩散范围缩小至采煤机背风侧0~5 m;人行道附近的粉尘带形态也转变为低浓度的粉尘带。经室内试验,选择超声雾化喷嘴作为最终喷嘴,在相同的水气压力为0.4 MPa的条件下,使用该喷嘴配备的负压喷雾集尘器,有效范围为5.03 m,雾化角为71°。将研制的负压喷雾捕集器应用于塔山煤矿5110综采环境中,有效降低靠近人行道作业区推进支架的粉尘浓度,平均总降尘率和呼吸降尘率分别达到81.5%和79.1%,证实了该装置具有良好的降尘效果。 展开更多
关键词 粉尘 煤矿综采环境 负压喷雾收集器 数值模拟
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Effect of N-substituents on performance of thiourea collectors by density functional theory calculations 被引量:14
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作者 刘广义 钟宏 +2 位作者 夏柳荫 王帅 戴塔根 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第4期695-701,共7页
Using density functional methods,some properties were studied such as the energies and compositions of frontier molecular orbitals and the atomic charges,which are related to the reactive behavior of thioureas contain... Using density functional methods,some properties were studied such as the energies and compositions of frontier molecular orbitals and the atomic charges,which are related to the reactive behavior of thioureas containing different N-substituent groupings.The calculation results indicate that the N-substituent groupings have significant effect on the flotation performance of thiourea collectors.The order of electron-donating ability is N-propyl-N'-benzyl-thiourea(PBZYTU)>N-propyl-N'-ethyl-thiourea (PETU)>N-propyl-N'-allyl-thiourea(PALTU)>>N-propyl-N'-acetyl-thiourea(PACTU)>N-propyl-N'-ethoxycarbonyl-thiourea (PECTU)>N-propyl-N'-benzoyl-thiourea(PBZOYTU),and the order of feedback-electron-accepting ability is PBZOYTU> PACTU>PECTU>>PALTU>PETU>PBZYTU.This implies that PBZOYTU,PACTU or PECTU can react with copper atoms having(t2g) 6 (eg) 3Cu(II)or t 6e 4Cu(I)configuration on the surfaces of copper sulfide minerals through normal covalent bond and back donation covalent bond,and exhibit excellently collecting performance for copper sulfide minerals.These are consistent with the experimental data reported in the literatures. 展开更多
关键词 thiourea collector sulfide ore structure-activity relationship density functional method
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