Solvent extraction,a separation and purification technology,is crucial in critical metal metallurgy.Organic solvents commonly used in solvent extraction exhibit disadvantages,such as high volatility,high toxicity,and ...Solvent extraction,a separation and purification technology,is crucial in critical metal metallurgy.Organic solvents commonly used in solvent extraction exhibit disadvantages,such as high volatility,high toxicity,and flammability,causing a spectrum of hazards to human health and environmental safety.Neoteric solvents have been recognized as potential alternatives to these harmful organic solvents.In the past two decades,several neoteric solvents have been proposed,including ionic liquids(ILs)and deep eutectic solvents(DESs).DESs have gradually become the focus of green solvents owing to several advantages,namely,low toxicity,degradability,and low cost.In this critical review,their classification,formation mechanisms,preparation methods,characterization technologies,and special physicochemical properties based on the most recent advancements in research have been systematically described.Subsequently,the major separation and purification applications of DESs in critical metal metallurgy were comprehensively summarized.Finally,future opportunities and challenges of DESs were explored in the current research area.In conclusion,this review provides valuable insights for improving our overall understanding of DESs,and it holds important potential for expanding separation and purification applications in critical metal metallurgy.展开更多
With the application of Distributed Acoustic Sensors(DAS)across various infrastructures,it will play a pivotal role in shaping smart cities in the future.However,the current single-source detection and identification ...With the application of Distributed Acoustic Sensors(DAS)across various infrastructures,it will play a pivotal role in shaping smart cities in the future.However,the current single-source detection and identification technology might struggle to meet the high precision needs in the intricate environmental conditions of mixed multi-source interference.We propose a new deep neural network-based multi-source signal separation method for DAS and accomplish the separation performance of this method under practical applications.In addition,a new evaluation metric for the separation method is proposed in conjunction with the separation and identification of DAS mixed signals.For mixed signals with different source numbers,the recognizable rate of separated signals can reach 98.33%on average.This study provides a promising solution to the multi-source mixed interference problem faced by DAS in complex environments.展开更多
The process of deep reduction and magnetic separation was proposed to enrich nickel and iron from laterite nickel ores.Results show that nickel-iron concentrates with nickel grade of 6.96%,nickel recovery of 94.06%,ir...The process of deep reduction and magnetic separation was proposed to enrich nickel and iron from laterite nickel ores.Results show that nickel-iron concentrates with nickel grade of 6.96%,nickel recovery of 94.06%,iron grade of 34.74%,and iron recovery of 80.44% could be obtained after magnetic separation under the conditions of reduction temperature of 1275℃,reduction time of 50 min,slag basicity of 1.0,carbon-containing coefficient of 2.5,and magnetic field strength of 72 kA/m.Reduction temperature and time affected the possibility of deep reduction and reaction progress.Slag basicity affected the composition of slag in burden and the spilling and enriching rate of nickel-iron from a matrix to form nickel-iron particles.Nickel-iron particles were generated,aggregated,and grew gradually in the reduction process.Nickel-iron particles can be effectively separated from gangue minerals by magnetic separation.展开更多
Deep eutectic solvents(DESs) were used for luminescence measurements in quantitative analysis of trivalent lanthanide ions and as solvents for light rare earth elements(LREE) in solid-liquid separation.The spectroscop...Deep eutectic solvents(DESs) were used for luminescence measurements in quantitative analysis of trivalent lanthanide ions and as solvents for light rare earth elements(LREE) in solid-liquid separation.The spectroscopic characteristics of lanthanide chlorides LnCl3(Ln=Eu,Tb),respectively their aquo complexes,are described in a comprehensive study that demonstrates the significant enhancement of the phosphorescence emission intensity in DESs as polar and weakly coordinating solvent.Several DESs stabilize the lanthanide ion luminescence against changes in temperature and moisture,which is advantageous compared with the use of ionic liquids.Small amounts of water lead in certain eutectic systems even to a further increase in phosphorescence emission intensity.By investigating the solubility of lanthanide sesquioxides Ln2 O3(Ln=La,Nd,Sm,Eu,Gd,Tb,Dy) in DESs,selectivities are identified that may be of use for the separation of LREE.展开更多
Pyromellitic acid(PMA)and trimellitic acid(TMA)are significant chemical raw materials and intermediates.They simultaneously exist in the industry processes of synthesis and are difficult to be separated.In this work,s...Pyromellitic acid(PMA)and trimellitic acid(TMA)are significant chemical raw materials and intermediates.They simultaneously exist in the industry processes of synthesis and are difficult to be separated.In this work,several kinds of biodegradable compounds were chosen as hydrogen bond acceptors(HBAs)to separate PMA and TMA mixtures from acetone solutions via forming deep eutectic solvent(DES).It has been found that all these compounds can separate PMA and TMA mixtures to obtain pure PMA or TMA.However,the interaction between HBAs and PMA or TMA is quite different.Choline chloride cannot extract TMA but can form a DES with PMA in acetone.Hexamethylenetetramine(HA)and L-carnitine(L-car)can form DESs with both PMA and TMA in acetone solution.But when L-car or HA is added,the extraction rate of PMA is larger than that of TMA until the extraction rate of PMA reach 100%,and pure TMA is left in the acetone solution.The selective separation mechanism was explored by infrared spectroscopy combined with quantum chemistry calculation,and the strength and site of the interaction between extractants with PMA and TMA were calculated.展开更多
The efficient separation and collection of ammonia(NH_(3))during NH_(3) synthesis process is essential to improve the economic efficiency and protect the environment.In this work,ethanolammonium hydrochloride(EtOHACl)...The efficient separation and collection of ammonia(NH_(3))during NH_(3) synthesis process is essential to improve the economic efficiency and protect the environment.In this work,ethanolammonium hydrochloride(EtOHACl)and phenol(PhOH)were used to prepare a novel class of deep eutectic solvents(DESs)with multiple active sites and low viscosities.The NH_(3) separation performance of EtOHACl+PhOH DESs was analyzed completely.It is figured out that the NH_(3) absorption rates in EtOHACl+PhOH DESs are very fast.The NH_(3) absorption capacities are very high and reach up to 5.52 and 10.74 mol·kg1 at 11.2 and 100.4 kPa under 298.2 K,respectively.In addition,the EtOHACl+PhOH DESs present highly selective absorption of NH_(3) over N_(2) and H_(2) and good regenerative properties after seven cycles of absorption/desorption.The intrinsic separation mechanism of NH_(3) by EtOHACl+PhOH DESs was further revealed by spectroscopic analysis and quantum chemistry calculations.展开更多
Copper nanosheets and sulfur particles were synthesized synchronously by electrolysis,after dissolving Cu_(2)S in ChCl-thiourea(TU)deep eutectic solvent(DES)system.The optimized electrolysis conditions of 0.9 V,80℃,a...Copper nanosheets and sulfur particles were synthesized synchronously by electrolysis,after dissolving Cu_(2)S in ChCl-thiourea(TU)deep eutectic solvent(DES)system.The optimized electrolysis conditions of 0.9 V,80℃,and 2 h resulted in the deposition of pure nano-sized copper sheets with a length of approximately 500 nm and a thickness of approximately 30 nm,and the production of sulfur particles with an average size of approximately 10μm.The morphology of the cathodic products was significantly influenced by the electrolysis voltage.When Cu_(2)S was introduced into ChCl-TU,it dissolved[CuCl_(2)]^(-)without disrupting the structure of the choline ion(Ch^(+)).As the electrolysis time increased,the copper deposition changed from wire to sheet growth,with the growth direction from radial to epitaxial along the substrate and back to radial.展开更多
Multiple suppression is an important element of marine seismic data processing.Intelligent suppression of multiples us-ing artificial intelligence reduces labor costs,minimizes dependence on unknown prior information,...Multiple suppression is an important element of marine seismic data processing.Intelligent suppression of multiples us-ing artificial intelligence reduces labor costs,minimizes dependence on unknown prior information,and improves data processing ef-ficiency.In this study,we propose an intelligent method for suppressing marine seismic multiples using deep learning approaches.The proposed method enables the intelligent suppression of free-surface-related multiples from seismic records.Initially,we construct a multi-category marine seismic multiple dataset through finite difference forward modeling under different boundary conditions.We use various models and data augmentation methods,including sample rotation,noise addition,and random channel omission.Then,we apply depthwise separable convolution to develop our deep learning Mobilenet-Unet model.The Mobilenet-Unet framework sig-nificantly reduces the number of operations required for multiple elimination without sacrificing model performance,ultimately reali-zing the optimal multiple suppression model.The trained Mobilenet-Unet is applied to the test set for verification.Moreover,to deter-mine its generalization ability,it is implemented to seismic records containing multiples generated by two marine geophysical models that were not included in the training process.The performance of Mobilenet-Unet is also compared with that of different network structures.The results indicate that,despite its small size,our proposed Mobilenet-Unet deep learning model can rapidly and effective-ly separate multiples in marine seismic data,possessing reasonable generalization ability.展开更多
A laboratory experiment was carried out to extract iron from oolitic iron ore by a deep reduction and magnetic separation technique. The raw coal with fixed carbon of 66.54% was used as the reductant. The iron was suc...A laboratory experiment was carried out to extract iron from oolitic iron ore by a deep reduction and magnetic separation technique. The raw coal with fixed carbon of 66.54% was used as the reductant. The iron was successfully extracted from the oolitic iron ore which otherwise is nearly impossible to be separated due to its extremely fine-grain and mosaic nature. The results showed that an iron recovery rate of 90.78% and an iron content of 92.53~ of iron concentrate could be obtained by such a technique. The optimized roast temperature is 1 200℃ and time is 60 min. The subsequent magnetic separation was performed by using a magnetic field intensity of 111 kA · m^-1 and a grinding fineness less than 45 μm of 96. 19% for the sintered product.展开更多
In this paper,we summarize recent progresses made in deep learning based acoustic models and the motivation and insights behind the surveyed techniques.We first discuss models such as recurrent neural networks(RNNs) a...In this paper,we summarize recent progresses made in deep learning based acoustic models and the motivation and insights behind the surveyed techniques.We first discuss models such as recurrent neural networks(RNNs) and convolutional neural networks(CNNs) that can effectively exploit variablelength contextual information,and their various combination with other models.We then describe models that are optimized end-to-end and emphasize on feature representations learned jointly with the rest of the system,the connectionist temporal classification(CTC) criterion,and the attention-based sequenceto-sequence translation model.We further illustrate robustness issues in speech recognition systems,and discuss acoustic model adaptation,speech enhancement and separation,and robust training strategies.We also cover modeling techniques that lead to more efficient decoding and discuss possible future directions in acoustic model research.展开更多
In this study,we investigated the separation of iron and scandium from Sc-bearing red mud.The red mud object of our study contained 31.11 wt%total iron(TFe),0.0045 wt%Sc,hematite(Fe_(2)O_(3))and ferrosilite(FeO·S...In this study,we investigated the separation of iron and scandium from Sc-bearing red mud.The red mud object of our study contained 31.11 wt%total iron(TFe),0.0045 wt%Sc,hematite(Fe_(2)O_(3))and ferrosilite(FeO·SiO_(2))as the main Fe-bearing minerals.The Sc-bearing red mud was treated by a novel deep reduction roasting and magnetic separation process that includes the addition of coke and CaO to extract Fe and enriching Sc from the Sc-bearing red mud.The addition of coke and CaO enhances the transformation of hematite(Fe_(2)O_(3))to metallic iron(Fe~0)and magnetite(Fe_(3)O_(4))as well as the transformation of ferrosilite into metallic iron(Fe~0).The test results show that utilizing the new process a Fe concentrate with a TFe content of 81.22 wt%and Fe recovery of 92.96%was obtained.Furthermore,magnetic separation tailings with Sc content of 0.0062 wt%and Sc recovery of 98.65%were also obtained.The test results were achieved under the following process conditions:roasting temperature of 1373 K,roasting time of 45 min,calcium oxide dosage of 20 wt%,coke dosage of 25 wt%,grinding fineness of90%<0.04 mm,and magnetic field intensity of 0.24 T.The major minerals in the Fe concentrate are metallic iron(Fe~0)and magnetite(Fe_(3)O_(4)).The main minerals in the magnetic separation tailings with a low TFe content of 2.62%are CaO·SiO_(2),Na_(2)O·SiO_(2),FeO·SiO_(2),Ca_(3)Fe_(2)Si_(3)O_(12),CaAl_(2)SiO_6 and CaFe(SiO_(3))_(2).展开更多
Audio-visual learning,aimed at exploiting the relationship between audio and visual modalities,has drawn considerable attention since deep learning started to be used successfully.Researchers tend to leverage these tw...Audio-visual learning,aimed at exploiting the relationship between audio and visual modalities,has drawn considerable attention since deep learning started to be used successfully.Researchers tend to leverage these two modalities to improve the performance of previously considered single-modality tasks or address new challenging problems.In this paper,we provide a comprehensive survey of recent audio-visual learning development.We divide the current audio-visual learning tasks into four different subfields:audiovisual separation and localization,audio-visual correspondence learning,audio-visual generation,and audio-visual representation learning.State-of-the-art methods,as well as the remaining challenges of each subfield,are further discussed.Finally,we summarize the commonly used datasets and challenges.展开更多
A hydrophobic carbon dots(Glc-OCDs)derived from octadecylamine and glucose were successfully synthesized for the first time and then grafted onto the porous silica surface by the“Nano-on-Micro”strategy,which was ser...A hydrophobic carbon dots(Glc-OCDs)derived from octadecylamine and glucose were successfully synthesized for the first time and then grafted onto the porous silica surface by the“Nano-on-Micro”strategy,which was served as a new stationary phase(Sil-Glc-OCDs)for reversed-phase liquid chromatography.The structure of this stationary phase was carefully verified by laser scanning confocal microscope,Fourier transform infrared spectrometry,elemental analysis,contact angle measurement,etc.Several analytes including seven polycyclic aromatic hydrocarbons,eight alkylbenzenes,eight phenols and seven sulfonamides can be well separated on this stationary phase.Better separation performance for certain analytes over commercial C_(18) column was obtained.Interestingly,this stationary phase exhibited excellent chromatographic selectivity in the separation of the isomers of tert‑butylbenzene,sec‑butylbenzene,isobutylbenzene and n-butylbenzene.In addition,this new Sil-Glc-OCDs column was also applied for detection of calycosin-7-glucoside,ononin,calycosin,formononetin,genistein and isorhamnetin in the extract of Radix Astragali,which were found that the concentration was 0.15 g/L,0.088 g/L,0.14 g/L,0.086 g/L,0.18 g/L and 0.29 g/L,respectively.We believe that this CDs-grafted silica materials are promising for chromatographic separation.展开更多
Levulinic acid(LA)is one of the top-12 most promising biomass-based platform chemicals,which has a wide range of applications in a variety of fields.However,separation and purification of LA from aqueous solution or a...Levulinic acid(LA)is one of the top-12 most promising biomass-based platform chemicals,which has a wide range of applications in a variety of fields.However,separation and purification of LA from aqueous solution or actual hydrolysate continues to be a challenge.Among various downstream separation technologies,liquid-liquid extraction is a low-cost,effective,and simple process to separate LA.The key breakthrough lies in the development of extractants with high extraction efficiency,good hydrophobicity,and low cost.In this work,three hydrophobic deep eutectic solvents(DESs)based on tri-n-octylamine(TOA)as hydrogen bond acceptor(HBA)and alcohols(butanol,2-octanol,and menthol)as hydrogen bond donors(HBDs)were developed to extract LA from aqueous solution.The molar ratios of HBD and HBA,extraction temperature,contact time,solution pH,and initial LA concentration,DES/water volume ratios were systematically investigated.Compared with 2-octanol-TOA and menthol-TOA DES,the butanol-TOA DES exhibited the superior extraction performance for LA,with a maximum extraction efficiency of 95.79±1.4%.Moreover,the solution pH had a great impact on the LA extraction efficiency of butanol-TOA(molar ratio=3:1).It is worth noting that the extraction equilibrium time was less than 0.5 h.More importantly,the butanol-TOA(3:1)DES possesses good extraction abilities for low,medium,and high concentrations of LA.展开更多
基金financially supported by the Original Exploration Project of the National Natural Science Foundation of China(No.52150079)the National Natural Science Foundation of China(Nos.U22A20130,U2004215,and 51974280)+1 种基金the Natural Science Foundation of Henan Province of China(No.232300421196)the Project of Zhongyuan Critical Metals Laboratory of China(Nos.GJJSGFYQ202304,GJJSGFJQ202306,GJJSGFYQ202323,GJJSGFYQ202308,and GJJSGFYQ202307)。
文摘Solvent extraction,a separation and purification technology,is crucial in critical metal metallurgy.Organic solvents commonly used in solvent extraction exhibit disadvantages,such as high volatility,high toxicity,and flammability,causing a spectrum of hazards to human health and environmental safety.Neoteric solvents have been recognized as potential alternatives to these harmful organic solvents.In the past two decades,several neoteric solvents have been proposed,including ionic liquids(ILs)and deep eutectic solvents(DESs).DESs have gradually become the focus of green solvents owing to several advantages,namely,low toxicity,degradability,and low cost.In this critical review,their classification,formation mechanisms,preparation methods,characterization technologies,and special physicochemical properties based on the most recent advancements in research have been systematically described.Subsequently,the major separation and purification applications of DESs in critical metal metallurgy were comprehensively summarized.Finally,future opportunities and challenges of DESs were explored in the current research area.In conclusion,this review provides valuable insights for improving our overall understanding of DESs,and it holds important potential for expanding separation and purification applications in critical metal metallurgy.
文摘With the application of Distributed Acoustic Sensors(DAS)across various infrastructures,it will play a pivotal role in shaping smart cities in the future.However,the current single-source detection and identification technology might struggle to meet the high precision needs in the intricate environmental conditions of mixed multi-source interference.We propose a new deep neural network-based multi-source signal separation method for DAS and accomplish the separation performance of this method under practical applications.In addition,a new evaluation metric for the separation method is proposed in conjunction with the separation and identification of DAS mixed signals.For mixed signals with different source numbers,the recognizable rate of separated signals can reach 98.33%on average.This study provides a promising solution to the multi-source mixed interference problem faced by DAS in complex environments.
基金Projects(51904058,51734005)supported by the National Natural Science Foundation of ChinaProject(2018YFC1901901902)supported by the National Key Research and Development Program of China
文摘The process of deep reduction and magnetic separation was proposed to enrich nickel and iron from laterite nickel ores.Results show that nickel-iron concentrates with nickel grade of 6.96%,nickel recovery of 94.06%,iron grade of 34.74%,and iron recovery of 80.44% could be obtained after magnetic separation under the conditions of reduction temperature of 1275℃,reduction time of 50 min,slag basicity of 1.0,carbon-containing coefficient of 2.5,and magnetic field strength of 72 kA/m.Reduction temperature and time affected the possibility of deep reduction and reaction progress.Slag basicity affected the composition of slag in burden and the spilling and enriching rate of nickel-iron from a matrix to form nickel-iron particles.Nickel-iron particles were generated,aggregated,and grew gradually in the reduction process.Nickel-iron particles can be effectively separated from gangue minerals by magnetic separation.
基金Project supported by the ForCYCLE program of the Bavarian State Ministry of the Environment and Consumer Protection (BAF01SoFo-65211)。
文摘Deep eutectic solvents(DESs) were used for luminescence measurements in quantitative analysis of trivalent lanthanide ions and as solvents for light rare earth elements(LREE) in solid-liquid separation.The spectroscopic characteristics of lanthanide chlorides LnCl3(Ln=Eu,Tb),respectively their aquo complexes,are described in a comprehensive study that demonstrates the significant enhancement of the phosphorescence emission intensity in DESs as polar and weakly coordinating solvent.Several DESs stabilize the lanthanide ion luminescence against changes in temperature and moisture,which is advantageous compared with the use of ionic liquids.Small amounts of water lead in certain eutectic systems even to a further increase in phosphorescence emission intensity.By investigating the solubility of lanthanide sesquioxides Ln2 O3(Ln=La,Nd,Sm,Eu,Gd,Tb,Dy) in DESs,selectivities are identified that may be of use for the separation of LREE.
基金financially supported by the National Natural Science Foundation of China(21676019 and 21776199).
文摘Pyromellitic acid(PMA)and trimellitic acid(TMA)are significant chemical raw materials and intermediates.They simultaneously exist in the industry processes of synthesis and are difficult to be separated.In this work,several kinds of biodegradable compounds were chosen as hydrogen bond acceptors(HBAs)to separate PMA and TMA mixtures from acetone solutions via forming deep eutectic solvent(DES).It has been found that all these compounds can separate PMA and TMA mixtures to obtain pure PMA or TMA.However,the interaction between HBAs and PMA or TMA is quite different.Choline chloride cannot extract TMA but can form a DES with PMA in acetone.Hexamethylenetetramine(HA)and L-carnitine(L-car)can form DESs with both PMA and TMA in acetone solution.But when L-car or HA is added,the extraction rate of PMA is larger than that of TMA until the extraction rate of PMA reach 100%,and pure TMA is left in the acetone solution.The selective separation mechanism was explored by infrared spectroscopy combined with quantum chemistry calculation,and the strength and site of the interaction between extractants with PMA and TMA were calculated.
基金supported by the National Natural Science Foundation of China(22221005 and 22008033).
文摘The efficient separation and collection of ammonia(NH_(3))during NH_(3) synthesis process is essential to improve the economic efficiency and protect the environment.In this work,ethanolammonium hydrochloride(EtOHACl)and phenol(PhOH)were used to prepare a novel class of deep eutectic solvents(DESs)with multiple active sites and low viscosities.The NH_(3) separation performance of EtOHACl+PhOH DESs was analyzed completely.It is figured out that the NH_(3) absorption rates in EtOHACl+PhOH DESs are very fast.The NH_(3) absorption capacities are very high and reach up to 5.52 and 10.74 mol·kg1 at 11.2 and 100.4 kPa under 298.2 K,respectively.In addition,the EtOHACl+PhOH DESs present highly selective absorption of NH_(3) over N_(2) and H_(2) and good regenerative properties after seven cycles of absorption/desorption.The intrinsic separation mechanism of NH_(3) by EtOHACl+PhOH DESs was further revealed by spectroscopic analysis and quantum chemistry calculations.
基金the financial support from the National Natural Science Foundation of China(Nos.51904005,52304362)the Key Research Foundation of University in Anhui Province,China(No.2023AH051113)+1 种基金the Key Laboratory of Ionic Rare Earth Resources and Environment,Ministry of Natural Resources,China(No.2022IRERE203)the Distinguished Young Research Project of Anhui Higher Education Institution,China(No.2023AH020017)。
文摘Copper nanosheets and sulfur particles were synthesized synchronously by electrolysis,after dissolving Cu_(2)S in ChCl-thiourea(TU)deep eutectic solvent(DES)system.The optimized electrolysis conditions of 0.9 V,80℃,and 2 h resulted in the deposition of pure nano-sized copper sheets with a length of approximately 500 nm and a thickness of approximately 30 nm,and the production of sulfur particles with an average size of approximately 10μm.The morphology of the cathodic products was significantly influenced by the electrolysis voltage.When Cu_(2)S was introduced into ChCl-TU,it dissolved[CuCl_(2)]^(-)without disrupting the structure of the choline ion(Ch^(+)).As the electrolysis time increased,the copper deposition changed from wire to sheet growth,with the growth direction from radial to epitaxial along the substrate and back to radial.
基金supported by the Key Laboratory of Ma-rine Mineral Resources,Ministry of Natural Resources,Guangzhou(No.KLMMR-2022-G09)the Guangzhou Ba-sic Research Program-Basic and Basic Applied Research Project(No.2023A04J0917)the PI Project of South-ern Marine Science and Engineering Guangdong Labora-tory(Guangzhou)(No.GML2020GD0802).
文摘Multiple suppression is an important element of marine seismic data processing.Intelligent suppression of multiples us-ing artificial intelligence reduces labor costs,minimizes dependence on unknown prior information,and improves data processing ef-ficiency.In this study,we propose an intelligent method for suppressing marine seismic multiples using deep learning approaches.The proposed method enables the intelligent suppression of free-surface-related multiples from seismic records.Initially,we construct a multi-category marine seismic multiple dataset through finite difference forward modeling under different boundary conditions.We use various models and data augmentation methods,including sample rotation,noise addition,and random channel omission.Then,we apply depthwise separable convolution to develop our deep learning Mobilenet-Unet model.The Mobilenet-Unet framework sig-nificantly reduces the number of operations required for multiple elimination without sacrificing model performance,ultimately reali-zing the optimal multiple suppression model.The trained Mobilenet-Unet is applied to the test set for verification.Moreover,to deter-mine its generalization ability,it is implemented to seismic records containing multiples generated by two marine geophysical models that were not included in the training process.The performance of Mobilenet-Unet is also compared with that of different network structures.The results indicate that,despite its small size,our proposed Mobilenet-Unet deep learning model can rapidly and effective-ly separate multiples in marine seismic data,possessing reasonable generalization ability.
基金Item Sponsored by National Natural Science Foundation of China(51074036)
文摘A laboratory experiment was carried out to extract iron from oolitic iron ore by a deep reduction and magnetic separation technique. The raw coal with fixed carbon of 66.54% was used as the reductant. The iron was successfully extracted from the oolitic iron ore which otherwise is nearly impossible to be separated due to its extremely fine-grain and mosaic nature. The results showed that an iron recovery rate of 90.78% and an iron content of 92.53~ of iron concentrate could be obtained by such a technique. The optimized roast temperature is 1 200℃ and time is 60 min. The subsequent magnetic separation was performed by using a magnetic field intensity of 111 kA · m^-1 and a grinding fineness less than 45 μm of 96. 19% for the sintered product.
文摘In this paper,we summarize recent progresses made in deep learning based acoustic models and the motivation and insights behind the surveyed techniques.We first discuss models such as recurrent neural networks(RNNs) and convolutional neural networks(CNNs) that can effectively exploit variablelength contextual information,and their various combination with other models.We then describe models that are optimized end-to-end and emphasize on feature representations learned jointly with the rest of the system,the connectionist temporal classification(CTC) criterion,and the attention-based sequenceto-sequence translation model.We further illustrate robustness issues in speech recognition systems,and discuss acoustic model adaptation,speech enhancement and separation,and robust training strategies.We also cover modeling techniques that lead to more efficient decoding and discuss possible future directions in acoustic model research.
基金Project supported by the Sichuan Science and Technology Program(2022YFS0462,2021YJ0057,2021YFG0268)the China Postdoctoral Science Foundation(2014M560734)。
文摘In this study,we investigated the separation of iron and scandium from Sc-bearing red mud.The red mud object of our study contained 31.11 wt%total iron(TFe),0.0045 wt%Sc,hematite(Fe_(2)O_(3))and ferrosilite(FeO·SiO_(2))as the main Fe-bearing minerals.The Sc-bearing red mud was treated by a novel deep reduction roasting and magnetic separation process that includes the addition of coke and CaO to extract Fe and enriching Sc from the Sc-bearing red mud.The addition of coke and CaO enhances the transformation of hematite(Fe_(2)O_(3))to metallic iron(Fe~0)and magnetite(Fe_(3)O_(4))as well as the transformation of ferrosilite into metallic iron(Fe~0).The test results show that utilizing the new process a Fe concentrate with a TFe content of 81.22 wt%and Fe recovery of 92.96%was obtained.Furthermore,magnetic separation tailings with Sc content of 0.0062 wt%and Sc recovery of 98.65%were also obtained.The test results were achieved under the following process conditions:roasting temperature of 1373 K,roasting time of 45 min,calcium oxide dosage of 20 wt%,coke dosage of 25 wt%,grinding fineness of90%<0.04 mm,and magnetic field intensity of 0.24 T.The major minerals in the Fe concentrate are metallic iron(Fe~0)and magnetite(Fe_(3)O_(4)).The main minerals in the magnetic separation tailings with a low TFe content of 2.62%are CaO·SiO_(2),Na_(2)O·SiO_(2),FeO·SiO_(2),Ca_(3)Fe_(2)Si_(3)O_(12),CaAl_(2)SiO_6 and CaFe(SiO_(3))_(2).
基金supported by National Key Research and Development Program of China(No.2016YFB1001001)Beijing Natural Science Foundation(No.JQ18017)National Natural Science Foundation of China(No.61976002)。
文摘Audio-visual learning,aimed at exploiting the relationship between audio and visual modalities,has drawn considerable attention since deep learning started to be used successfully.Researchers tend to leverage these two modalities to improve the performance of previously considered single-modality tasks or address new challenging problems.In this paper,we provide a comprehensive survey of recent audio-visual learning development.We divide the current audio-visual learning tasks into four different subfields:audiovisual separation and localization,audio-visual correspondence learning,audio-visual generation,and audio-visual representation learning.State-of-the-art methods,as well as the remaining challenges of each subfield,are further discussed.Finally,we summarize the commonly used datasets and challenges.
基金financial support from Science and Technology Project of Science and Technology Bureau of Chengguan District in Lanzhou City(No.2020JSCX0033)National Natural Science Foundation of China(No.21822407)+1 种基金Youth Innovation Pro-motion Association CASthe National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT:Ministry of Science and ICT)(No.NRF-2019R1A2C1010032).
文摘A hydrophobic carbon dots(Glc-OCDs)derived from octadecylamine and glucose were successfully synthesized for the first time and then grafted onto the porous silica surface by the“Nano-on-Micro”strategy,which was served as a new stationary phase(Sil-Glc-OCDs)for reversed-phase liquid chromatography.The structure of this stationary phase was carefully verified by laser scanning confocal microscope,Fourier transform infrared spectrometry,elemental analysis,contact angle measurement,etc.Several analytes including seven polycyclic aromatic hydrocarbons,eight alkylbenzenes,eight phenols and seven sulfonamides can be well separated on this stationary phase.Better separation performance for certain analytes over commercial C_(18) column was obtained.Interestingly,this stationary phase exhibited excellent chromatographic selectivity in the separation of the isomers of tert‑butylbenzene,sec‑butylbenzene,isobutylbenzene and n-butylbenzene.In addition,this new Sil-Glc-OCDs column was also applied for detection of calycosin-7-glucoside,ononin,calycosin,formononetin,genistein and isorhamnetin in the extract of Radix Astragali,which were found that the concentration was 0.15 g/L,0.088 g/L,0.14 g/L,0.086 g/L,0.18 g/L and 0.29 g/L,respectively.We believe that this CDs-grafted silica materials are promising for chromatographic separation.
基金supported by the Key Area Research&Development Program of Guangdong Province(2020B0101070001)the National Natural Science Foundation of China(21978053,51508547)。
文摘Levulinic acid(LA)is one of the top-12 most promising biomass-based platform chemicals,which has a wide range of applications in a variety of fields.However,separation and purification of LA from aqueous solution or actual hydrolysate continues to be a challenge.Among various downstream separation technologies,liquid-liquid extraction is a low-cost,effective,and simple process to separate LA.The key breakthrough lies in the development of extractants with high extraction efficiency,good hydrophobicity,and low cost.In this work,three hydrophobic deep eutectic solvents(DESs)based on tri-n-octylamine(TOA)as hydrogen bond acceptor(HBA)and alcohols(butanol,2-octanol,and menthol)as hydrogen bond donors(HBDs)were developed to extract LA from aqueous solution.The molar ratios of HBD and HBA,extraction temperature,contact time,solution pH,and initial LA concentration,DES/water volume ratios were systematically investigated.Compared with 2-octanol-TOA and menthol-TOA DES,the butanol-TOA DES exhibited the superior extraction performance for LA,with a maximum extraction efficiency of 95.79±1.4%.Moreover,the solution pH had a great impact on the LA extraction efficiency of butanol-TOA(molar ratio=3:1).It is worth noting that the extraction equilibrium time was less than 0.5 h.More importantly,the butanol-TOA(3:1)DES possesses good extraction abilities for low,medium,and high concentrations of LA.
