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Experimental and mechanistic study on iron extraction from high-iron red mud under multiple physical field coupling conditions
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作者 DONG Hai-pei YANG Jin-lin +3 位作者 ZHOU Wen-tao YU Xu-yang MA Shao-jian WANG Ding-zheng 《Journal of Central South University》 2025年第7期2476-2486,共11页
Red mud is a solid waste discharged in the process of alumina production,and how to realize the efficient recovery of its iron is an urgent problem to be solved.In this study,the iron extraction test and mechanism stu... Red mud is a solid waste discharged in the process of alumina production,and how to realize the efficient recovery of its iron is an urgent problem to be solved.In this study,the iron extraction test and mechanism study of high iron red mud were carried out under the coupling conditions of multiple physical field(microwave field,gas-solid flow field and temperature field)with biomass as the reducing agent.The test results showed that under the optimal conditions,an iron concentrate with a yield of 78.4%,an iron grade of 59.23%,and a recovery rate of 86.65%was obtained.The analyses of XRD,XPS,TEM,and SEM-EDS showed that during the roasting process,the hematite in the high-iron red mud was completely converted to magnetite,and the biomass produced the reductant that provided the magnetization reaction;A large number of cracks and pores appeared in the surface of the hematite reduction product particles,which helped to induce iron minerals to undergo effective mineral phase transformation.The above study provides ideas for the phase transformation and efficient recovery of iron minerals in red mud. 展开更多
关键词 multiple physical field high-iron red mud BIOMASS mineral phase transformation iron extraction
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Tomato Growth Height Prediction Method by Phenotypic Feature Extraction Using Multi-modal Data
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作者 GONG Yu WANG Ling +3 位作者 ZHAO Rongqiang YOU Haibo ZHOU Mo LIU Jie 《智慧农业(中英文)》 2025年第1期97-110,共14页
[Objective]Accurate prediction of tomato growth height is crucial for optimizing production environments in smart farming.However,current prediction methods predominantly rely on empirical,mechanistic,or learning-base... [Objective]Accurate prediction of tomato growth height is crucial for optimizing production environments in smart farming.However,current prediction methods predominantly rely on empirical,mechanistic,or learning-based models that utilize either images data or environmental data.These methods fail to fully leverage multi-modal data to capture the diverse aspects of plant growth comprehensively.[Methods]To address this limitation,a two-stage phenotypic feature extraction(PFE)model based on deep learning algorithm of recurrent neural network(RNN)and long short-term memory(LSTM)was developed.The model integrated environment and plant information to provide a holistic understanding of the growth process,emploied phenotypic and temporal feature extractors to comprehensively capture both types of features,enabled a deeper understanding of the interaction between tomato plants and their environment,ultimately leading to highly accurate predictions of growth height.[Results and Discussions]The experimental results showed the model's ef‐fectiveness:When predicting the next two days based on the past five days,the PFE-based RNN and LSTM models achieved mean absolute percentage error(MAPE)of 0.81%and 0.40%,respectively,which were significantly lower than the 8.00%MAPE of the large language model(LLM)and 6.72%MAPE of the Transformer-based model.In longer-term predictions,the 10-day prediction for 4 days ahead and the 30-day prediction for 12 days ahead,the PFE-RNN model continued to outperform the other two baseline models,with MAPE of 2.66%and 14.05%,respectively.[Conclusions]The proposed method,which leverages phenotypic-temporal collaboration,shows great potential for intelligent,data-driven management of tomato cultivation,making it a promising approach for enhancing the efficiency and precision of smart tomato planting management. 展开更多
关键词 tomato growth prediction deep learning phenotypic feature extraction multi-modal data recurrent neural net‐work long short-term memory large language model
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Mass Spectrometry-based Deep Coverage Proteome:Evaluation of Cellular Protein Extraction Methods
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作者 XU Xia QIN Weida +3 位作者 LI Ruomeng WANG Qianqian LIU Ning LI Gongyu 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2024年第11期98-107,共10页
The current study comprehensively evaluates four different protein extraction methods based on urea,sodium dodecyl sulfate(SDS),anionic surfactants(BT),and total RNA extractor(Trizol),aiming to optimize the sample pre... The current study comprehensively evaluates four different protein extraction methods based on urea,sodium dodecyl sulfate(SDS),anionic surfactants(BT),and total RNA extractor(Trizol),aiming to optimize the sample preparation workflow for mass spectrometry-based proteomics.Using HeLa cells as an example,we found that the method employing the mass spectrometry-compatible surfactant BT reagent significantly reduces the total time consumed for protein extraction and minimizes protein losses during the sample preparation process.Further integrating the four protein extraction methods,we identified over 7000 proteins from HeLa cells without relying on pre-fractionation techniques,and 2990 of them were quantified using label-free quantification.It is worth noting that the BT and SDS methods demonstrate higher efficiency in extracting membrane proteins,while the Urea and Trizol methods are more effective in extracting proteins from nuclear and cytoplasmic fractions.In summary,this study provides a novel solution for deep proteome coverage,particularly in the context of cellular protein extraction,by integrating mass spectrometry-compatible surfactants with traditional extraction methods to effectively enhance protein identification numbers. 展开更多
关键词 SURFACTANT Protein extraction PROTEOMICS Mass spectrometry
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An air combat maneuver pattern extraction based on time series segmentation and clustering analysis
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作者 Zhifei Xi Yingxin Kou +2 位作者 Zhanwu Li Yue Lv You Li 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第6期149-162,共14页
Target maneuver recognition is a prerequisite for air combat situation awareness,trajectory prediction,threat assessment and maneuver decision.To get rid of the dependence of the current target maneuver recognition me... Target maneuver recognition is a prerequisite for air combat situation awareness,trajectory prediction,threat assessment and maneuver decision.To get rid of the dependence of the current target maneuver recognition method on empirical criteria and sample data,and automatically and adaptively complete the task of extracting the target maneuver pattern,in this paper,an air combat maneuver pattern extraction based on time series segmentation and clustering analysis is proposed by combining autoencoder,G-G clustering algorithm and the selective ensemble clustering analysis algorithm.Firstly,the autoencoder is used to extract key features of maneuvering trajectory to remove the impacts of redundant variables and reduce the data dimension;Then,taking the time information into account,the segmentation of Maneuver characteristic time series is realized with the improved FSTS-AEGG algorithm,and a large number of maneuver primitives are extracted;Finally,the maneuver primitives are grouped into some categories by using the selective ensemble multiple time series clustering algorithm,which can prove that each class represents a maneuver action.The maneuver pattern extraction method is applied to small scale air combat trajectory and can recognize and correctly partition at least 71.3%of maneuver actions,indicating that the method is effective and satisfies the requirements for engineering accuracy.In addition,this method can provide data support for various target maneuvering recognition methods proposed in the literature,greatly reduce the workload and improve the recognition accuracy. 展开更多
关键词 Maneuver pattern extraction Data mining Fuzzy segmentation Selective ensemble clustering
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Studies on the anti-hair loss mechanism of Aquilaria sinensis leaf extract by integrated metabolomics and network pharmacology
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作者 Zhengang Peng Zhengwan Huang +1 位作者 Zhe Liu Xiaoxiao Lin 《日用化学工业(中英文)》 北大核心 2025年第6期767-778,共12页
The anti-hair loss mechanism of Aquilaria sinensis leaf extract(ASE)has been studied by using metabolomics and network pharmacology.Metabolomics was utilized to comprehensively identify the active constituents of ASE,... The anti-hair loss mechanism of Aquilaria sinensis leaf extract(ASE)has been studied by using metabolomics and network pharmacology.Metabolomics was utilized to comprehensively identify the active constituents of ASE,and the network pharmacology was used to elucidate their anti-hair loss mechanism,which was verified by molecular docking technology.572 active compounds were identified from the ASE by metabolomics methods,where there are 1447 corresponding targets and 492 targets related to hair loss,totaling 88 targets.20 core active substances were identified by constructing a network between common targets and active substances,which include vanillic acid,chorionic acid,caffeic acid and apigenin.The five key targets of TNF,TP53,IL6,PPARG,and EGFR were screened out by the PPI network analysis on 88 common targets.The GO and KEGG pathway enrichment analysis showed that the inflammation,hormone balance,cell growth,proliferation,apoptosis,and oxidative stress are involved.Molecular docking studies have confirmed the high binding affinity between core active compounds and key targets.The drug similarity assessment on these core compounds suggested that they have the potential to be used as potential hair loss treatment drugs.This study elucidates the complex molecular mechanism of ASE in treating hair loss,and provides a reference for the future applications in hair care products. 展开更多
关键词 metabolomics network pharmacology hair loss Aquilaria sinensis leaf extract molecular docking
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MICROWAVE-ASSISTED EXTRACTION OF GLYCYRRHIZIC ACID FROM LICORICE ROOT-EFFECT OF THE PROPERTY OF SOLUTION ON EXTRACTION OF GA 被引量:53
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作者 Pan Xuejun and Liu Huizhou (Young Scienctist Laboratory of Separation Science & Engineering, State Key Laboratory of Biochemical Engineering, Instigate of Chemical Metallurgy, Chinese Academy of Sciepces, Beijing 100080) 《化工学报》 EI CAS CSCD 北大核心 2000年第S1期240-243,共4页
The property of extraction solution is an important factor influencing the extraction efficiency. In the present work, the effect of the property of solution on extraction of GA was studied, which including the concen... The property of extraction solution is an important factor influencing the extraction efficiency. In the present work, the effect of the property of solution on extraction of GA was studied, which including the concentration of ethanol, ammonia and cation (M+), pH of extraction solution, different kinds of organic solvent etc. The results show that 50%-60%(v/v) ethanol can reach high percentage extraction of GA. If 1% (v/v) ammonia solution was added into 60%(v/v) ethanol, the percentage extraction can be increased from 2.0% to 2.31%. Without ammonia, 50mmol/L [M+] (M+ = K+, NH4+) was added into 60%(v/v) ethanol, percentage extraction of GA can reach about 2.26%. If pH of solution (60% ethanol) was adjust to pH=4.0, it can reach high percentage extraction. If pH of solution (60% ethanol + 50mmol [M+], pH=6.1) was adjust tO PH=4.0, especially M+ is K+ or NH4+, it can reach almost same extraction efficiency as that of 1% ammonia solution + 60% ethanol, and the operation environment can be greatly improved. 展开更多
关键词 glycyrrhizic acid licorice root MICROWAVE-ASSISTED extraction
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Kinetic Mechanisms for Preparing Silymarin via Microwave-assisted Extraction 被引量:7
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作者 Xu Xiang-wen Zheng Xian-zhe +2 位作者 Sun Yu Wang Xin Liu Cheng-hai 《Journal of Northeast Agricultural University(English Edition)》 CAS 2013年第2期53-60,共8页
The kinetic mechanism for the preparation of silymarin from milk thistle seeds was studied during the microwave-assisted extraction (MAE) process. The results showed that the transfer rate of silymarin from milk thi... The kinetic mechanism for the preparation of silymarin from milk thistle seeds was studied during the microwave-assisted extraction (MAE) process. The results showed that the transfer rate of silymarin from milk thistle seeds increased with the microwave output power and temperature during MAE processing. The apparent extraction rate constant k (s-1) was 1.2028×10-2 , 1.2248×10-2 , and 1.2485×10-2 , and diffusion coefficient D (m2·s-1 ) was 4.21×10-10, 4.29×10-10 , and 4.37×10-10 at the microwave temperatures of 383, 393, and 403 K, respectively, in the silymarin MAE process. With the help of scanning electron microscopy (SEM), the microstructures of the samples extracted by MAE were observed. The results revealed that the increased efficiency and rate of MAE of silymarin could be attributed mainly to the subsequent cell change resulting from superheating effects during MAE. 展开更多
关键词 MICROWAVE extraction SILYMARIN apparent extraction rate constant diffusion coefficient
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Component Content Soft-sensor Based on Neural Networks in Rare-earth Countercurrent Extraction Process 被引量:13
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作者 YANG Hui CHAI Tian-You 《自动化学报》 EI CSCD 北大核心 2006年第4期489-495,共7页
Throught fusion of the mechanism modeling and the neural networks modeling,a compo- nent content soft-sensor,which is composed of the equilibrium calculation model for multi-component rare earth extraction and the err... Throught fusion of the mechanism modeling and the neural networks modeling,a compo- nent content soft-sensor,which is composed of the equilibrium calculation model for multi-component rare earth extraction and the error compensation model of fuzzy system,is proposed to solve the prob- lem that the component content in countercurrent rare-earth extraction process is hardly measured on-line.An industry experiment in the extraction Y process by HAB using this hybrid soft-sensor proves its effectiveness. 展开更多
关键词 RARE-EARTH countercurrent extraction soft-sensor equilibrium calculation model neural networks
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Feature evaluation and extraction based on neural network in analog circuit fault diagnosis 被引量:16
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作者 Yuan Haiying Chen Guangju Xie Yongle 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第2期434-437,共4页
Choosing the right characteristic parameter is the key to fault diagnosis in analog circuit. The feature evaluation and extraction methods based on neural network are presented. Parameter evaluation of circuit feature... Choosing the right characteristic parameter is the key to fault diagnosis in analog circuit. The feature evaluation and extraction methods based on neural network are presented. Parameter evaluation of circuit features is realized by training results from neural network; the superior nonlinear mapping capability is competent for extracting fault features which are normalized and compressed subsequently. The complex classification problem on fault pattern recognition in analog circuit is transferred into feature processing stage by feature extraction based on neural network effectively, which improves the diagnosis efficiency. A fault diagnosis illustration validated this method. 展开更多
关键词 Fault diagnosis Feature extraction Analog circuit Neural network Principal component analysis.
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Characteristics, Enzymatic Extraction of Pectin from Shaddock 被引量:4
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作者 XIE Lian-wu GUO Ya-ping ZHOU Chun-shan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2005年第2期105-107,共3页
Pectins had been extracted from shaddock raw material with 0.01 mol·L^-1 HCI and with three enzymic preparations including cellulase from aspergillus oryzaei.β -glucosidase from almonds and protopectinases-T, a ... Pectins had been extracted from shaddock raw material with 0.01 mol·L^-1 HCI and with three enzymic preparations including cellulase from aspergillus oryzaei.β -glucosidase from almonds and protopectinases-T, a protopectin-solubilizing enzyme, which did not degrade polygalacturonic acid, The effects of enzymic and acid soluhilization of pectin from shaddock materials were compared, The yield of pectin preparations, degree of acetylation, gelling strength, molecular weight and viscosity were determined. Enzymic methods of extraction gave much bigger yields of pectic substances. Compared with the pectin extracted with hydrochloric acid, all the samples derived from shaddock raw material with enzymic preparations had a significant lower D-galacturonic acid content. 展开更多
关键词 SHADDOCK enzymic extraction PECTIN
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Improved method for the feature extraction of laser scanner using genetic clustering 被引量:6
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作者 Yu Jinxia Cai Zixing Duan Zhuohua 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第2期280-285,共6页
Feature extraction of range images provided by ranging sensor is a key issue of pattern recognition. To automatically extract the environmental feature sensed by a 2D ranging sensor laser scanner, an improved method b... Feature extraction of range images provided by ranging sensor is a key issue of pattern recognition. To automatically extract the environmental feature sensed by a 2D ranging sensor laser scanner, an improved method based on genetic clustering VGA-clustering is presented. By integrating the spatial neighbouring information of range data into fuzzy clustering algorithm, a weighted fuzzy clustering algorithm (WFCA) instead of standard clustering algorithm is introduced to realize feature extraction of laser scanner. Aimed at the unknown clustering number in advance, several validation index functions are used to estimate the validity of different clustering algorithms and one validation index is selected as the fitness function of genetic algorithm so as to determine the accurate clustering number automatically. At the same time, an improved genetic algorithm IVGA on the basis of VGA is proposed to solve the local optimum of clustering algorithm, which is implemented by increasing the population diversity and improving the genetic operators of elitist rule to enhance the local search capacity and to quicken the convergence speed. By the comparison with other algorithms, the effectiveness of the algorithm introduced is demonstrated. 展开更多
关键词 laser scanner feature extraction weighted fuzzy clustering validation index genetic algorithm.
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Extraction and purification of the polysaccharides in Hippohaere rhamnoides L. 被引量:4
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作者 XU Yaqin JIN Ting +1 位作者 YU Zeyuan FU Hong 《Journal of Northeast Agricultural University(English Edition)》 CAS 2007年第2期153-156,共4页
The different extraction technology and purification technology ofHippohpae rhamoides polysaccharides were researched in the paper. The best method of papain extraction were obtained, the ratio of papain 2%, pH at 5.5... The different extraction technology and purification technology ofHippohpae rhamoides polysaccharides were researched in the paper. The best method of papain extraction were obtained, the ratio of papain 2%, pH at 5.5, temperature at 45℃ and extraction time of 20 min were suitable for papain extraction. The highest content of Hippohpae rhamoides polysaccharides was 44.28 mg·g^-1. The optimum process of ultrasonic extraction were obtained, namely extracted for 55 min at 480 W with the material ratio of 1:20. The highest content of Hippohpae rhamoides polysaccharides was 48.63 mg·g^-1. The results showed that the ultrasonic and papain extraction together was the best method, the content was 54.30 mg·g^-1. After the removing protein, pigment and dialysis. Two fraction were separated from the purified Hippohpae rhamoides by DEAE-cellulose chromatography, the main fraction was collected finally. The fraction was identified by Sepharose CL-4B gel filtration. Ultraviolet spectrometry, freeze-thawing analysis showed that fraction was purified. Its molecular weight was probably 109.4 ku. 展开更多
关键词 Hippophae rhamoides L. POLYSACCHARIDES extraction PURIFICATION
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Effect of Process Parameters of Microwave Assisted Extraction (MAE) on Polysaccharides Yield from Pumpkin 被引量:13
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作者 ZHENG Xianzhe YIN Fangping LIU Chenghai XU Xiangwen 《Journal of Northeast Agricultural University(English Edition)》 CAS 2011年第2期79-86,共8页
Process parameters of microwave assisted extraction (MAE) of the polysaccharides from pumpkin viz. extraction temperature, time and liquid-solid ratio were studied by using single factor and response surface methodo... Process parameters of microwave assisted extraction (MAE) of the polysaccharides from pumpkin viz. extraction temperature, time and liquid-solid ratio were studied by using single factor and response surface methodology method. The results showed that the liquid-solid ratio was the most important factor in polysaccharides yield, followed the extraction temperature was the least important factor. The optimum microwave assisted extraction co by ndi extraction time, and tions for the highest polysaccharides yield from pumpkin (16.76%-4-0.38%) were obtained by using the response surface methodology with extraction time of 29 min, an extraction temperature of 79 ℃ and a liquid-solid ratio of 22 mL·g^-1. Validation experiment result well agreed with predicted value. 展开更多
关键词 pumpkin polysaccharides microwave assisted extraction (MAE) response surface methodology (RSM)
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Recovery of zinc from low-grade zinc oxide ores by solvent extraction 被引量:8
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作者 覃文庆 蓝卓越 黎维中 《Journal of Central South University of Technology》 2003年第2期98-102,共5页
The recovery of zinc from low-grade zinc oxide ores with solvent extraction-electrowinning technique was investigated by using D2EHPA as extractant and 260 # kerosene as diluent. The results show that it is possible t... The recovery of zinc from low-grade zinc oxide ores with solvent extraction-electrowinning technique was investigated by using D2EHPA as extractant and 260 # kerosene as diluent. The results show that it is possible to selectively leach zinc from the ores by heap leaching. The zinc concentration of leach solution in the first leaching cycle is 32.57 g/L, and in the sixteenth cycle the zinc concentration is 8.27g/L after solvent extraction. The leaching solution is subjected to solvent extraction, scrubbing and selective stripping for enrichment of zinc and removal of impurities. The pregnant zinc sulfate solution produced from the stripping cycle is suitable for zinc electrowinning. Extra-pure zinc metal was obtained in the electrowinning test under conventional conditions. 展开更多
关键词 ZINC LOW-GRADE ZINC oxide ORES HEAP LEACHING SOLVENT extraction
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Pulse-to-pulse periodic signal sorting features and feature extraction in radar emitter pulse sequences 被引量:5
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作者 Qiang Guo Zhenshen Qu Changhong Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第3期382-389,共8页
A novel class of periodically changing features hidden in radar pulse sequence environment,named G features,is proposed.Combining fractal theory and Hilbert-Huang transform,the features are extracted using changing ch... A novel class of periodically changing features hidden in radar pulse sequence environment,named G features,is proposed.Combining fractal theory and Hilbert-Huang transform,the features are extracted using changing characteristics of pulse parameters in radar emitter signals.The features can be applied in modern complex electronic warfare environment to address the issue of signal sorting when radar emitter pulse signal parameters severely or even completely overlap.Experiment results show that the proposed feature class and feature extraction method can discriminate periodically changing pulse sequence signal sorting features from radar pulse signal flow with complex variant features,therefore provide a new methodology for signal sorting. 展开更多
关键词 signal sorting fractal geometry Hilbert-Huang transform(HHT) G feature extraction.
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Extraction Separation of Germanium with Hydroxamic Acid HGS98 被引量:2
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作者 TANG Shu-fang ZHOU Chun-shan +1 位作者 JIANG Xin-yu ZHAO Chun-lei 《Journal of Central South University》 SCIE EI CAS 2000年第1期40-42,共3页
The extraction separation of germanium from indium raffinate in hydrometallurgical zinc process was discussed. The conditions and mechanism of the extraction with hydroxamic acid HGS98 have been investigated in detail... The extraction separation of germanium from indium raffinate in hydrometallurgical zinc process was discussed. The conditions and mechanism of the extraction with hydroxamic acid HGS98 have been investigated in detail. The results show that u sing 2% (mass fraction) hydroxamic acid HGS98 and 5% D 2EHPA as synergist, germanium is extracted (1 stage) over 99% in 5 min at phase ratio ( V o∶ V a) of 1∶5 from indium raffinate with original acidity. Then, using 2 mol·L -1 NH 4F as strip liquor, the stripping recovery is over 98% in 15 min at phase ratio of 1∶1. This process has the following advantages:easy to operate, high recovery and selectivity, and lower investment cost. It provides a new way to recover rare metal-germanium from metallurgical spent residues. 展开更多
关键词 extraction SEPARATION GERMANIUM hydroxamic ACID HGS98
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Recovery of iron and rare earth elements from red mud through an acid leaching-stepwise extraction approach 被引量:35
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作者 ZHANG Xue-kai ZHOU Kang-gen +3 位作者 CHEN Wei LEI Qing-yuan HUANG Ying PENG Chang-hong 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第2期458-466,共9页
A feasible approach to selectively recover iron and rare earth elements(REEs)from red mud through acid leaching-coordination-solvent extraction was proposed.The leaching efficiencies of Fe,Al,Ti,Sc,La,Ce,Nd and Y can ... A feasible approach to selectively recover iron and rare earth elements(REEs)from red mud through acid leaching-coordination-solvent extraction was proposed.The leaching efficiencies of Fe,Al,Ti,Sc,La,Ce,Nd and Y can reach up to 95.9%,82.1%,68.3%,93.3%,82.3%,96.9%,98.3%and 95.6%,respectively,under the optimal condition in the leaching process.Aliquat 336 showed excellent extraction performance of iron in chloride-rich solution,and the maximum extraction efficiency can reach over 96%in one time extraction while the loss of other metals was less than 10%,under the condition of Aliquat 336 concentration(v/v)of 30%,aqueous-organic ratio of 1.0 and extraction time of 20 min.Furthermore,P204 can effectively extract the scandium while Al and most other REEs remain in the aqueous phase.This approach may provide a new insight for the recovery of valuable resources from red mud. 展开更多
关键词 red mud IRON rare earth elements LEACHING solvent extraction
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THE SYNERGISTIC MECHANISM OF SOLVENT EXTRACTION OF GOLD IN HCl MEDIA WITH TOA AND TOPO 被引量:1
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作者 Yang Tianzu Shui Chenjing Bin Wanda (Department of Nonferrous Metallurgy, Central South University of Technology, Changsha 410083, China) 《Journal of Central South University》 SCIE EI CAS 1999年第1期29-32,共4页
The mechanism of synergistic extraction of gold in HCl media was researched with tri n octyl amine(TOA) and tri n octyl phospine oxide(TOPO). It was determined that the composition of synergistic extract is (TOAHT... The mechanism of synergistic extraction of gold in HCl media was researched with tri n octyl amine(TOA) and tri n octyl phospine oxide(TOPO). It was determined that the composition of synergistic extract is (TOAHTOPO)AuCl 4; the constant of synergistic extracting equilibrium is 10 9.20 ; and the synergistic reaction is exothermic with -17.187 kJ/K·mol of Δ H 298 . The extraction mechanism was also studied by the IR spectra and UV spectra. It is found that the extraction mechanism belongs to ion association type. 展开更多
关键词 GOLD SYNERGISTIC extraction hydrochloric acid MEDIA MECHANISM of extraction
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Extraction process of chlorogenic acid in flos lonicerae by enzymatic treatment 被引量:4
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作者 刘佳佳 赵国玲 +1 位作者 王晖 章晓骅 《Journal of Central South University of Technology》 2002年第4期246-249,共4页
A new method of extracting chlorogenic acid from flos lonicerae, and treating the materials with enzyme before being extracted by ethanol is developed, and the optimum conditions are also investigated in detail. Three... A new method of extracting chlorogenic acid from flos lonicerae, and treating the materials with enzyme before being extracted by ethanol is developed, and the optimum conditions are also investigated in detail. Three important factors, enzyme dosage, treatment time and treatment temperature are adapted to optimize the extraction process. The experimental results show that the extract yield of flos lonicerae and chlorogenic acid can be obviously increased by the cellulase treatment, 61.5 mg chlorogenic acid is obtained from 1.00 g flos lonicerae at most. The optimal temperature of enzymatic treatment is 40 50 ℃. Compared with the use of single cellulase, the combined treatment of cellulase and pectinase increase the extract yield obviously but fail to improve that of chlorogenic acid. 展开更多
关键词 flos lonicerae chlorogenic ACID ENZYMATIC TREATMENT extract PROCESS
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Saliency detection and edge feature matching approach for crater extraction 被引量:2
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作者 An Liu Donghua Zhou +1 位作者 Lixin Chen Maoyin Chen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第6期1291-1300,共10页
Craters are salient terrain features on planetary surfaces, and provide useful information about the relative dating of geological unit of planets. In addition, they are ideal landmarks for spacecraft navigation. Due ... Craters are salient terrain features on planetary surfaces, and provide useful information about the relative dating of geological unit of planets. In addition, they are ideal landmarks for spacecraft navigation. Due to low contrast and uneven illumination, automatic extraction of craters remains a challenging task. This paper presents a saliency detection method for crater edges and a feature matching algorithm based on edges informa- tion. The craters are extracted through saliency edges detection, edge extraction and selection, feature matching of the same crater edges and robust ellipse fitting. In the edges matching algorithm, a crater feature model is proposed by analyzing the relationship between highlight region edges and shadow region ones. Then, crater edges are paired through the effective matching algorithm. Experiments of real planetary images show that the proposed approach is robust to different lights and topographies, and the detection rate is larger than 90%. 展开更多
关键词 CRATER automatic extraction visual saliency featurematching edge detection.
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