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Effects of Ultrasound-Assisted Alkaline Extraction on the Structural and Emulsifying Properties of Chickpea Protein Isolate
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作者 ZHANG Yixue YANG Qing +4 位作者 CHENG Teng ZHENG Ruihan MA Wuchao HE Xiangli LI Ke 《食品科学》 北大核心 2025年第19期236-247,共12页
This study aimed to investigate the effect of ultrasound-assisted alkaline extraction(UAE)(at 20 kHz and different powers of 0,200,300,400,500 and 600 W for 10 min)on the yield,structure and emulsifying properties of ... This study aimed to investigate the effect of ultrasound-assisted alkaline extraction(UAE)(at 20 kHz and different powers of 0,200,300,400,500 and 600 W for 10 min)on the yield,structure and emulsifying properties of chickpea protein isolate(CPI).Compared with the non-ultrasound group,ultrasound treatment at 400 W resulted in the largest increase in CPI yield,and both the particle size and turbidity decreased with increasing ultrasound power from 0 to 400 W.The scanning electron microscope results showed a uniform structural distribution of CPI.Moreover,itsα-helix content increased,β-sheet content decreased,and total sulfhydryl group content and endogenous fluorescence intensity rose,illustrating that UAE changed the secondary and tertiary structure of CPI.At 400 W,the solubility of the emulsion increased to 63.18%,and the best emulsifying properties were obtained;the emulsifying activity index(EAI)and emulsifying stability index(ESI)increased by 85.42%and 46.78%,respectively.Furthermore,the emulsion droplets formed were smaller and more uniform.In conclusion,proper UAE power conditions increased the extraction yield and protein content of CPI,and effectively improved its structure and emulsifying characteristics. 展开更多
关键词 CHICKPEA ULTRASOUND extraction yield protein structure functional properties
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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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A rapid soil DNA extraction method applied to field detection
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作者 YAN Jingying NI Liang +1 位作者 LI Kunfeng SHEN Xingyu 《浙江大学学报(农业与生命科学版)》 北大核心 2025年第4期586-595,共10页
Soil DNA extraction,such as microbial community analysis and gene drift detection,is an important basis for multiple analyses in different fields.Nevertheless,the soil DNA extraction methods for field detection are st... Soil DNA extraction,such as microbial community analysis and gene drift detection,is an important basis for multiple analyses in different fields.Nevertheless,the soil DNA extraction methods for field detection are still lacking.This study established a rapid soil DNA extraction(RSDE)method that can be used in field detection.In this method,we first utilized the optimized lysate to isolate DNA from soil and then used a filtration membrane and a DNA adsorption membrane to purify the DNA via the column method.Moreover,we used the pressure from the syringe instead of the conventional centrifugal force of the centrifuge to assist the sample filtration,resulting in very low requirements for this method,with an extraction time of less than 20 min.Furthermore,we demonstrated that the RSDE method was applicable for DNA extraction from different types of soils,with the demand for soil samples as low as 0.1 g and that the amount of obtained DNA was,to some extent,greater than that obtained by a commercial kit.Further analysis revealed that this extracted genomic DNA can be used directly for polymerase chain reaction(PCR)analysis,including ordinary PCR,real-time fluorescent quantitative PCR,and recombinase polymerase amplification(RPA)-CRISPR/Cas12a visual assays.In addition,we demonstrated that this method can be used to extract DNA from residual plant roots in addition to soil microbes,which lays a foundation for the comprehensive analysis of soil plants and microorganisms.In summary,the RSDE method proposed in this study may have wide application prospects. 展开更多
关键词 soil DNA DNA extraction field detection polymerase chain reaction recombinase polymerase amplification(RPA)-CRISPR/Cas12a
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Advances in Industrial Extraction,Biological Activity and Application Value of Rutin
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作者 Guo Hongwei Li Yuanxin +5 位作者 Gui Qi Liu Taiyang Wen Xiuhua Li Yufang Liu Junhe He Nana 《Journal of Northeast Agricultural University(English Edition)》 2025年第3期86-96,共11页
Rutin,also known as vitamin P,belongs to the flavonoid class of compounds and is widely present in plants.Its ability to bind with albumin in the blood helps maintain capillary permeability,leading to its extensive us... Rutin,also known as vitamin P,belongs to the flavonoid class of compounds and is widely present in plants.Its ability to bind with albumin in the blood helps maintain capillary permeability,leading to its extensive use for cardiovascular protection.This review aimed to provide insights into the development of rutin raw material industry in China and its future applications in various fields,such as medicine,healthcare,food,and animal husbandry.The study began by comparing rutin quality standards across China,the United States and Europe,outlined the industrial extraction processes of rutin,and examined the biological activity and potential medical applications of rutin. 展开更多
关键词 RUTIN biological activity extraction process quality standard
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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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基于UPLC-Q-Extractive Orbitrap MS鉴定姜黄提取物在大鼠体内的代谢产物 被引量:6
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作者 王媛 刘美娟 +4 位作者 王宏进 殷光玲 李妍 张旭光 孙立新 《质谱学报》 EI CAS CSCD 北大核心 2022年第2期155-167,I0002,共14页
本研究基于超高效液相色谱-四极杆-静电场轨道阱高分辨质谱(UPLC-Q-Extractive Orbitrap MS),鉴定了姜黄提取物中姜黄素、去甲氧基姜黄素、双去甲氧基姜黄素3种姜黄素类化合物在大鼠体内的代谢产物。对健康雄性大鼠单剂量灌胃给予1703 m... 本研究基于超高效液相色谱-四极杆-静电场轨道阱高分辨质谱(UPLC-Q-Extractive Orbitrap MS),鉴定了姜黄提取物中姜黄素、去甲氧基姜黄素、双去甲氧基姜黄素3种姜黄素类化合物在大鼠体内的代谢产物。对健康雄性大鼠单剂量灌胃给予1703 mg/kg姜黄提取物(相当于480 mg/kg总姜黄素),收集粪便、尿液、胆汁、血浆生物样品,采用UPLC-Q-Extrative Orbitrap MS在负离子模式下鉴定代谢产物。在大鼠体内共鉴定出59个代谢物(B1~W12),其中B7、B8、B11~B13、C3、D3、D5、D8、D10、W1、W2、W4、W5、W7、W10为新发现的代谢产物,W3/W6、W11/W12、W12分别为血浆、粪便、尿液中首次发现的代谢产物。3种姜黄素类化合物在大鼠体内的代谢途径主要为葡萄糖醛酸化、硫酸酯化、还原氢化、氧化、还原、羟基化、去羟基化和多种反应类型的复合反应等。 展开更多
关键词 姜黄提取物 超高效液相色谱-四极杆-静电场轨道阱高分辨质谱(UPLC-Q-Extrative Orbitrap MS) 代谢产物
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Sonme Factors that Affect the Free Radical-scavenging Activity of Tea Extracts 被引量:9
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作者 Zhao Xinhuai ( Northeast Agricultural University, Harbin 150030 PRC) 《Journal of Northeast Agricultural University(English Edition)》 CAS 1999年第1期62-67,共6页
Some factors that affect the free radical-scavenging activety of two tea extracts were studied in vitro. It was found that concentration of tea extract or heating tea extract or treating with activated carbon and di... Some factors that affect the free radical-scavenging activety of two tea extracts were studied in vitro. It was found that concentration of tea extract or heating tea extract or treating with activated carbon and diatomite all had obvious effect on the scavenging activety of green tea extract ,but heating or treating with diaomite had less effect on the scavenging activity of black tea extract. Ascorbic acid, for having synergic effect with tea extracts, could enhance the scavenging activity of tea extracts markedly, and the contrary was cupric ion. Reducing sugars such as fructose and glucose also had some syncrgic effect to tea extracts. 展开更多
关键词 Tea extract. hydroxyl radical. free radival-scavenging activity
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Functional network and its application to extract information from chaotic communication
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作者 李卫斌 焦李成 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2004年第1期46-49,共4页
In chaotic communication system, the useful signal is hidden in chaotic signal, so the general method does not work well. Due to the random feature of chaotic signal, a functional networkbased method is presented. In ... In chaotic communication system, the useful signal is hidden in chaotic signal, so the general method does not work well. Due to the random feature of chaotic signal, a functional networkbased method is presented. In this method, the neural functions are selected from some complete function set for the functional network to reconstruct the chaotic signal, so the useful signal hidden in chaotic background is extracted. In addition, its learning algorithm is presented here and the example proves its good preformance. 展开更多
关键词 neural network functional network chaotic communication extract.
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Chrysanthemum extract alleviates acetaminophen-induced liver injury by inhibiting oxidative stress via AMPK pathway in rats 被引量:1
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作者 王春丽 谢欣梅 庞晓斌 《中国药理学与毒理学杂志》 CAS 北大核心 2019年第9期719-719,共1页
OBJECTIVE Acetaminophen(APAP),also known as paracetamol,is a commonly used antipyretic,anal⁃gesic and anti-inflammatory drug.However,during the use of APAP for more than half a century,people have not only used APAP t... OBJECTIVE Acetaminophen(APAP),also known as paracetamol,is a commonly used antipyretic,anal⁃gesic and anti-inflammatory drug.However,during the use of APAP for more than half a century,people have not only used APAP to fight diseases but have also suffered the adverse effects brought about by APAP for more than half a cen⁃tury.The most serious adverse reaction to APAP is hepatotoxicity caused by overdose or long-term use.In Chinese tra⁃ditional medicine,chrysanthemums have the functions of dispelling wind,dissipating heat,clearing the liver and improv⁃ing eyesight.Although the chrysanthemum variety named Bianliang ziyu from Kaifeng is not a medicinal variety,it has good value for medicine and food.The aim of this study was to investigate the protective effect of Bianliang Ziyu extract(BZE)on APAP-damaged rats and the potential molecular mechanism.METHODS Male Sprague-Dawley rats(200-220 g)were intragastrically administered BZE(110,220 and 440 mg·kg^-1)for 8 d.On the ninth day,APAP(800 mg·kg^-1)was administered intragastrically to the rats 0.5 h after BZE administration to induced drug-induced liver injury.The serum and liver samples were collected after 24 h.The levels of alanine aminotransferase(ALT),aspartic aminotransferase(AST),reactive oxygen species(ROS),malondialdehyde(MDA),superoxide dismutase(SOD)and glutathione(GSH)in serum and liver tissue of rats were detected by kit method.HE staining was used to observe the histopathological changes in the liver of rat.The effects of BZE on the expression of the oxidative stress related proteins and the mitochondrial biosyn⁃thesis related proteins were detected by Western blot.RESULTS The results showed that BZE significantly reduced the levels of ALT,AST,MDA and ROS and increased the levels of GSH and SOD caused by APAP.Moreover,BZE increased phosphorylation of AMP-activated protein kinase(AMPK)and glycogen synthase kinase 3β(GSK3β),promoted the nuclear translocation of nuclear factor-erythroid 2-related factor 2(Nrf2).BZE also upregulated the expression of mitochondrial biosynthesis related proteins such as peroxisome proliferator-activated receptorγ(PPAR-γ),peroxisome proliferator-activated receptorγcoactivator-1α(PGC-1α),mitochondrial transcription factor(TFAM)and nuclear respira⁃tory factor 1(NRF1).CONCLUSION BZE alleviates APAP-induced liver injury in rats by inhibiting oxidative stress via GSK3β-Nrf2 signaling and the mitochondrial biosynthesis pathway mediated by AMPK. 展开更多
关键词 ACETAMINOPHEN liver injury oxidative stress Chrysanthemum extract
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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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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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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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Recovery of iron and rare earth elements from red mud through an acid leaching-stepwise extraction approach 被引量:36
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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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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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Extraction of valuable metals from low-grade nickeliferous laterite ore by reduction roasting-ammonia leaching method 被引量:13
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作者 陈胜利 郭学益 +1 位作者 石文堂 李栋 《Journal of Central South University》 SCIE EI CAS 2010年第4期765-769,共5页
Nickel and cobalt were extracted from low-grade nickeliferous laterite ore using a reduction roasting-ammonia leaching method.The reduction roasting-ammonia leaching experimental tests were chiefly introduced,by which... Nickel and cobalt were extracted from low-grade nickeliferous laterite ore using a reduction roasting-ammonia leaching method.The reduction roasting-ammonia leaching experimental tests were chiefly introduced,by which fine coal was used as a reductant.The results show that the optimum process conditions are confirmed as follows:in reduction roasting process,the mass fraction of reductant in the ore is 10%,roasting time is 120 min,roasting temperature is 1 023-1 073 K;in ammonia leaching process,the liquid-to-solid ratio is 4:1(mL/g),leaching temperature is 313 K,leaching time is 120 min,and concentration ratio of NH3 to CO2 is 90 g/L:60 g/L.Under the optimum conditions,leaching efficiencies of nickel and cobalt are 86.25% and 60.84%,respectively.Therefore,nickel and cobalt can be effectively reclaimed,and the leaching agent can be also recycled at room temperature and normal pressure. 展开更多
关键词 low-grade nickeliferous laterite ore nickel COBALT reduction roasting ammonia leaching extractION
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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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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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Study on Optimization of Extraction Conditions of Platycodon grandiflorum A. DC Polysaccharide Using Response Surface Methodology 被引量:12
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作者 RUAN Zheng ZHOU Quan-cheng +1 位作者 DENG Ze-yuan YIN Yu-long 《食品科学》 EI CAS CSCD 北大核心 2008年第12期283-287,共5页
Platycodon grandiflorum A.DC.(PAl)C)root was taken as experiment material to extract polysaccharide.On the base of single factor tests(extraction time,extraction temperature,liquid-solid ratio,solvent pH value and NaC... Platycodon grandiflorum A.DC.(PAl)C)root was taken as experiment material to extract polysaccharide.On the base of single factor tests(extraction time,extraction temperature,liquid-solid ratio,solvent pH value and NaCl concentration),the study concluded the main factors affecting the extraction of PADC polysaccharide,which are liquid-solid ratio,extraction time and extraction temperature.Then through central-composite test design,the extraction conditions were concluded as liquid-solid ratio 34.43,extraction time 89.83 min and extraction temperature 52.47℃.By means of validation experiments,the adequacy of this model was confirmed. 展开更多
关键词 response surface methodology Platycodon grandiflorum A.DC POLYSACCHARIDE extraction conditions OPTIMIZATION
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Degradation of bond between steel bar and freeze-thaw concrete after electrochemical chloride extraction 被引量:8
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作者 郭育霞 贡金鑫 《Journal of Central South University》 SCIE EI CAS 2010年第2期388-393,共6页
The effect of electrochemical chloride extraction (ECE) on bond strength between steel bar and freeze-thaw concrete contaminated by chloride was experimentally investigated for beam specimens with dimensions of 100 ... The effect of electrochemical chloride extraction (ECE) on bond strength between steel bar and freeze-thaw concrete contaminated by chloride was experimentally investigated for beam specimens with dimensions of 100 mm × 100 mm × 400 ram. During the experiment, 3% NaC1 (vs mass of cement, mass fraction) was mixed into concrete to simulate chloride contamination, and the specimens experienced 0, 25, 50, 75 freeze-thaw cycles before ECE. In the process of ECE, different current densities and durations were adopted. It is indicated that the bond strength between reinforcement and concrete decreases with the increase of freeze-thaw cycles; the more the current and the electric quantity of ECE are, the more the loss of bond strength is; and the largest loss is up to 58.7%. So, it is important to choose proper parameters of ECE for the reinforced concrete structures contaminated by chloride and subjected to freeze-thaw cycles. 展开更多
关键词 CONCRETE bond strength DEGRADATION electrochemical chloride extraction freeze-thaw cycles
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