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Extractability and Mobility of Copper and Zinc Accumulated in Sandy Soils 被引量:6
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作者 ZHANG Ming-Kui HE Zhen-Li +1 位作者 D. V. CALVERT P. J. STOFFELLA 《Pedosphere》 SCIE CAS CSCD 2006年第1期43-49,共7页
Extractability and mobility of Cu and Zn and their relationships with 1) accumulation of Cu and Zn and 2) soil pH were studied in three sandy soils (Wabasso, Ankona, and Winder) from commercial citrus groves in Florid... Extractability and mobility of Cu and Zn and their relationships with 1) accumulation of Cu and Zn and 2) soil pH were studied in three sandy soils (Wabasso, Ankona, and Winder) from commercial citrus groves in Florida, USA. The soils, with a broad range of Cu and Zn concentrations, were fractionated by a modified procedure of Amacher, while Cu and Zn mobility were evaluated using column leaching. The extractability of Cu and Zn increased with decreasing soil pH. Also with increasing total soil Cu and Zn for extractable Cu in the Wabasso sand a threshold level, where the metal extraction rate increased, was noted at 100 mg kg-1, whereas for extractable Zn in the Wabasso sand the threshold level was found at 60 mg kg-1 and in the Ankona sand at 120 mg kg-1. These results suggested that the release potential of Cu and Zn was greater in the Wabasso sand than in the Ankona sand. The column leaching experiment showed that at total soil Cu or Zn concentrations < 100 mg kg-1 all leachates had low Cu and Zn concentrations. However at total concentrations > 200 mg kg-1 for Cu and > 150 mg kg-1 for Zn with decreasing soil pH, the concentrations of both Cu and Zn in the leachates increased exponentially. Also in these sandy soils soluble Cu and Zn mainly originated from the exchangeable fractions, and pH was a key factor controlling Cu and Zn extractability and mobility. 展开更多
关键词 COPPER extractability MOBILITY water quality ZINC
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Chemical forms and extractability of iron in sediments of three contrasting lakes of China and UK
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作者 ZHOUQi-xing GibsonC.E. StewartB.M. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2003年第6期728-733,共6页
Iron is a limiting factor for the eutrophication of lakes, especially those lakes that are enriched with phosphorus. Extractability of iron in sediments of West Lake and Taihu Lake in China and Lower Lough Erne in Nor... Iron is a limiting factor for the eutrophication of lakes, especially those lakes that are enriched with phosphorus. Extractability of iron in sediments of West Lake and Taihu Lake in China and Lower Lough Erne in Northern Ireland of UK was comparatively investigated on the basis of analysing chemical forms of iron using different extractants. It was shown that extractable iron in sediments of the lakes was greatly different using various extractants. Reactive iron or easily released iron such as “active' iron oxides, total free iron oxide and water-soluble iron was not high, only accounting for 0.01%—0.15% of total iron. The efficiency of the extractants for exchangeable iron was decreased in the sequence 0.1 mol/L HCl DTPA+TEA mixed solution > 1 mol/L NH 4OAc > 0.5 mol/L MgCl 2 = 0.5 mol/L CaCl 2. It seems that the complexion of iron by organic matter was not strong because the concentration of organically bound iron was significantly lower than the concentration it was forecasted. Extractable iron is not entirely consistent with or dependent on total iron in lake sediments. To a certain extent, phosphate can inhibit the release of iron in sediments of the lakes. The selection of extractants is thus the first key step to evaluate bioavailability of iron in lake sediments. 展开更多
关键词 IRON chemical form extractability lake sediment EUTROPHICATION
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Effect of Aging Organochlorine Pesticides in Various Soil Types on Their Extractability Using Selective Pressurized Liquid Extraction
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作者 Ahmed Hussen Negussie Megersa Jan Ake Jonsson 《Journal of Environmental Protection》 2017年第8期867-883,共17页
In this study, extractability of 13 organochlorine pesticides aged in six different soil types, was investigated. Acceptable recoveries were achieved for most of the analytes spiked into five of the soil types. No app... In this study, extractability of 13 organochlorine pesticides aged in six different soil types, was investigated. Acceptable recoveries were achieved for most of the analytes spiked into five of the soil types. No apparent correlation was perceptible between the soil characteristics and extractability of the aged analytes, signifying exhaustiveness of the extraction. However, recovery was considerably minimized (<75%) in the clay ensuring the hypothesis of study stating “extraction efficiency might be matrix dependent”. Therefore, the study demonstrates importance of optimizing extraction conditions even for those believed to be less prone to matrix effect, due to distinct properties of analyte-matrix interactions. 展开更多
关键词 Organochlorine Pesticides extractability Exhaustive Extraction Matrix Effect Soil Characteristics Analyte-Matrix Interactions
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Extractability of Cu in Alkaline Biosolids-Amended Soilsas Influenced by γ-Irradiation
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作者 LUOYONGMING P.CHRISTIE 《Pedosphere》 SCIE CAS CSCD 2002年第2期139-144,共6页
An incubation experiment was conducted to investigate themicrobial biomass associated Cu in four contrasting soils to which analkaline stabilised sewage sludge cake was applied. The organisms ofsludge- amended and con... An incubation experiment was conducted to investigate themicrobial biomass associated Cu in four contrasting soils to which analkaline stabilised sewage sludge cake was applied. The organisms ofsludge- amended and control soils were killed using γ-irradiationtechnique, and the aqueous and acid-extractable Cu concentrationswere determined. Addition of the sludge product increasedsignificantly the concentration of both the aqueous and diluteHOAc-extractable Cu in all the irradiated soils compared to thenon-sterilised sludge/soil mixtures, but the increase was morepronounced in the dilute acid-extractable Cu, indicating that the Curendered extractable in water and dilute acetic acid by γ-irradiation existed in the both soil liquid and solid phases. Theadditional increase in extractable Cu following the biocidaltreatment is likely to be due to release of Cu from the same fractionof soil microbial biomass. 展开更多
关键词 acetic acid extract aqueous extract γ-irradication soil biomasscopper
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Application of silver-based dihydric alcohol to the extraction of methyl linolenate with high extractability and stability replacing ionic liquids
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作者 Qianxia Chen Xianghong Lu Jianbing Ji 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第3期871-880,共10页
A novel silver-based dihydric alcohol extractant was substituted for ionic liquids to enrich methyl linolenate(C18-3)from tallow seed oil methyl ester in this study.The interactions among dihydric alcohol,Ag(I)and C18... A novel silver-based dihydric alcohol extractant was substituted for ionic liquids to enrich methyl linolenate(C18-3)from tallow seed oil methyl ester in this study.The interactions among dihydric alcohol,Ag(I)and C18-3 were explored by FT-IR spectroscopy.The effects of dihydric alcohol structure,carrier Ag(I)concentration,temperature and initial feed concentration on extraction yield and selectivity were reported.The good extraction performance was achieved by 1,4-butanediol containing AgBF4.The complexation of Ag(I)with C18-3 was dominant in extraction operation rather than physical partition.Furthermore,a multi-step reverse extraction method was proposed to obtain C18-3 product and regenerate the extractant.1-Hexene as the stripping phase can facilitate C18-3 reverse extraction.The content of C18-3 in the product was up to 93.36%,and the yield was 73.76%.This work opened a new route for the utilization of the dihydric alcohol properties to manipulate the carrier efficiency for extracting unsaturated fatty acid methyl esters at a lower cost. 展开更多
关键词 Liquid–liquid extraction Dihydric alcohol COMPLEXATION AgBF4 Reverse extraction
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Functional outcome and patient satisfaction 5y after laser vision correction
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作者 Ran Gao Yu Han +4 位作者 Jie Qin Yu-Shan Xu Yu Li Xiao-Tong Lyu Feng-Ju Zhang 《International Journal of Ophthalmology(English edition)》 2026年第1期123-131,共9页
AIM:To investigate the association between functionaloutcomes and postoperative patient satisfaction 5y aftersmall incision lenticule extraction(SMILE)and femtosecondlaser-assisted in situ keratomileusis(FS-LASIK).MET... AIM:To investigate the association between functionaloutcomes and postoperative patient satisfaction 5y aftersmall incision lenticule extraction(SMILE)and femtosecondlaser-assisted in situ keratomileusis(FS-LASIK).METHODS:This is a cross-sectional study.Thepatients underwent basic ophthalmic examinations,axiallength measurement,wide-field fundus photography,andaccommodation function testing.Behavioral habits datawere collected using a self-administered questionnaire,andvisual symptoms were assessed with the Quality of Vision(QoV)questionnaire.Postoperative satisfaction was alsorecorded.RESULTS:Totally 410 subjects[820 eyes,160males(39.02%)and 250 females(60.98%)]who hadundergone SMILE or FS-LASIK 5y ago were enrolled.Themean(standard deviation,SD)age of all patients was29.83y(6.69).The mean(SD)preoperative manifest SEwas-5.80(2.04)diopters(D;range:-0.88 to-13.75).Patient satisfaction at 5y after undergoing SMILE or FSLASIKwas 91.70%.Patients were categorized into twogroups:dissatisfied group and satisfied group.Significantdifferences were observed between the two groups in termsof age(P=0.012),sex(P=0.021),preoperative degreeof myopia(P=0.049),postoperative visual symptoms(frequency,P=0.043;severity,P<0.001;bothersome,P=0.018),difficulty driving at night(P=0.001),andaccommodative amplitude(AMP,P=0.020).Multivariateanalysis confirmed that female sex(P=0.024),severityof visual symptoms(P=0.009),and difficulty driving atnight(P=0.006)were significantly associated with lowersatisfaction.The dissatisfied group showed higher rates ofstarbursts,double or multiple images,and high myopia,but lower age.The frequency,severity,and bothersome ofdistortion exhibited decreased with increasing age.CONCLUSION:Patient satisfaction 5y after SMILEand FS-LASIK is high and stable.Difficulty driving at night,sex,and severity of visual symptoms are important factorsinfluencing patient satisfaction.Special attention should bepaid to younger highly myopic female patients,particularlythose with starbursts and double or multiple images.It is crucial to monitor postoperative visual outcomesand provide patients with comprehensive preoperativecounseling to enhance long-term satisfaction. 展开更多
关键词 patient satisfaction MYOPIA VISION small incision lenticule extraction femtosecond laser-assisted in situ keratomileusis
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Neuroprotective effects of Boswellia extract in animal models of ischemic stroke,Parkinson's disease,and Alzheimer's disease:a systematic review and meta-analysis
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作者 Meng-Ye Zhang Yu-Cheng Liao +7 位作者 Shan Liang Ji-Ping Yu Qian Meng Yi-Wen Wang Xing-F ang Zhang Wei Quan Ya-Jun Shi Yi Ding 《Traditional Medicine Research》 2026年第2期56-68,共13页
Background:Neurological disorders(NDs),including ischemic stroke(IS),Parkinson’s disease(PD),and Alzheimer’s disease(AD),are major contributors to global morbidity and mortality.Boswellia extract has demonstrated ne... Background:Neurological disorders(NDs),including ischemic stroke(IS),Parkinson’s disease(PD),and Alzheimer’s disease(AD),are major contributors to global morbidity and mortality.Boswellia extract has demonstrated neuroprotective properties,yet a comprehensive systematic review assessing its efficacy remains absent.This study aims to evaluate the efficacy of Boswellia extract in treating NDs,with a particular focus on its effects in AD and its potential for long-term neurorestoration,thereby supporting further investigation into Boswellia’s therapeutic role in ND management.Methods:A systematic literature search was performed in PubMed,Web of Science,ScienceDirect,and Google Scholar for English-language studies published up to March 2024.Eighteen studies met the inclusion criteria and were included in the meta-analysis.The study protocol was registered on PROSPERO(CRD42024524386).Eligible studies involved rodent models of IS,PD,or AD with post-operative interventions using Boswellia extract.Data extraction focused on mechanisms of action,dosages,treatment durations,and therapeutic outcomes.Studies were excluded if they involved non-ND models,combined treatments,or had incomplete data.Two researchers independently conducted literature screening and data extraction.Statistical analyses were conducted using Stata(version 17)and RevMan(version 5.4),employing fixed or random-effects models based on heterogeneity assessments.Result s:Boswellia extract significantly improved the mean effect size for NDs(ES=1.28,95%CI(1.05,1.51),P<0.001).Specifically,it reduced cerebral infarct volume in IS(SMD=−2.87,95%CI(−3.42,−2.32))and enhanced behavioral outcomes in AD(SMD=3.26,95%CI(2.07,5.14))and PD(SMD=5.37,95%CI(3.93,6.80)).Subgroup analyses revealed that Boswellia extract exhibited superior efficacy in AD when administered orally and via intra-cerebroventricular injection.Long-term treatment with Boswellia extract suggested potential neurorestorative effects.Additionally,Boswellia extract was more effective than its monomeric constituents,highlighting its promising role in ND treatment.Conclusion:Boswellia extract demonstrates significant neuroprotective effects across various NDs,particularly in AD and in promoting long-term neurorestoration.These findings support the need for further research into Boswellia’s potential as a therapeutic agent in the management of neurological disorders. 展开更多
关键词 Boswellic acid Boswellia extract ischemic stroke Parkinson’s disease Alzheimer’s disease META-ANALYSIS
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Molecular design of crown ethers .18.~1 Cationextractability and selectivities of selena-13- to 14-crown-4 被引量:1
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作者 刘育 张衡益 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2000年第1期66-68,共0页
Three selena-crown-4 derivatives have been prepared and their cation hinting abilities and selectivities with alkali and heavy metal ions have been evaluated by solvent extraction of aqueous metal picrates to show the... Three selena-crown-4 derivatives have been prepared and their cation hinting abilities and selectivities with alkali and heavy metal ions have been evaluated by solvent extraction of aqueous metal picrates to show the highest Ag+ extractability for novel benzo-selena-14-crown-4 (2,3-benzo-7, 12-diselena-1, 4-dioxacyclotetradecane-2-ene) over any other crown ethers. 展开更多
关键词 Selena crown ethers extractability SELECTIVITIES
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Field evidence of decreased extractability of copper and nickel added to soils in 6-year field experiments 被引量:1
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作者 Bao Jiang Dechun Su +2 位作者 Xiaoqing Wang Jifang Liu Yibing Ma 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2018年第2期71-77,共7页
The phytotoxicity of added copper (Cu) and nickel (Ni) is influenced by soil properties and field aging. However, the differences in the chemical behavior between Cu and Ni are still unclear. Theretbre, this study... The phytotoxicity of added copper (Cu) and nickel (Ni) is influenced by soil properties and field aging. However, the differences in the chemical behavior between Cu and Ni are still unclear. Theretbre, this study was conducted to investigate the extractability of added Cu and Ni in 6-year field experiments, as well as the link with their phytotoxicity. The results showed that the extractability of added Cu decreased by 6.63% (5.10% 7.90%), 22.5% (20.6e,~~23.9%), and 6.87% (0~17.9%) on average lbr acidic, neutral, and alkaline soil from 1 to 6 years, although the phytotoxicity of added Cu and Ni did not change significantly from 1 to 6 years in the long term field experiment. Because of dissolution of Cu, when the pH decreased below 7.0, the extractability of Cu in alkaline soil by EDTA at pH 4.0 could not reflect the effects of aging. For Ni, the extractability decreased by 18.1% (10.1e/~33.0%), 63.0% (59.2% 68.8%), and 22.0% (12.4% 31.8%) from 1 to 6 years in acidic, neutral, and alkaline soils, respectively, indicating the effects of aging on Ni were greater than on Cu. The sum of ten sequential extractions of Cu and Ni showed that added Cu was more extractable than Ni in neutral and alkaline soil, but similar in acidic soil. 展开更多
关键词 COPPER NICKEL EDTA Sequential extraction
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Assessment of mobile and potential mobile trace elements extractability in calcareous soils using different extracting agents
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作者 Mohsen Jalali Ziba Hurseresht 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2020年第1期109-125,共17页
Understanding trace elements mobility in soils,extracting agents,and their relationships with soil components,are essential for predicting their movement in soil profile and availability to plants.A laboratory study w... Understanding trace elements mobility in soils,extracting agents,and their relationships with soil components,are essential for predicting their movement in soil profile and availability to plants.A laboratory study was conducted to evaluate extractability of cadmium(Cd),cobalt(Co),copper(Cu),nickel(Ni),and zinc(Zn)from calcareous soils utilizing various extracting agents to be specific CaCU,DTPA,EDTA,HNO3,MgCl2,NaN03,NH4NO3,and NH4OAc.Cluster analysis indicated that DTPA and NH4OAc,HN03 and EDTA,and M gCl2 and NH4NO3 extracting agents yielded comparative values,whereas NaN03 and CaCl2 have shown different behavior than other extracting agents for all studied trace elements.The speciationof extracted trace elements in solutions indicated that in the CaCl2,NaN03,NH4NO3,and MgCl2 extracting agents most extracted Cd,Co,Ni,Zn,and part f Cu were as free ions and may be re-adsorbed on soils,leading to lower extractability,whereas,in the caseof HNO3 extracting agent,the likelihoodof re-adsorptionof trace elements may be little.The resultsof speciationof trace elements using NH4OAc DTPA,and EDTA extracting agents showed that Me-(Acetate)3,Me-(Acetate)2(aq),Me(DTPA)3-3-,Me(EDTA)2-.and MeH(EDTA)-complexes dominated in solutions indicating that the extracted trace elements may not be re-adsorbed on soils,leading to higher extractability.The resultsof this study are useful for short and long-term evaluationsof trace elements mobility and further environmental impacts. 展开更多
关键词 Mobility CALCAREOUS soils EXTRACTING AGENTS Trace elements
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Preparation of silver nanoparticles through the reduction of straw-extracted lignin and its antibacterial hydrogel 被引量:1
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作者 Lou Zhang Shuo Li +4 位作者 Fu Tang Jingkai Zhang Yuetong Kang Hean Zhang Lidong Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期504-514,共11页
Silver nanoparticles(Ag NPs)have attracted attention in the field of biomaterials due to their excellent antibacterial property.However,the reducing and stabilizing agents used for the chemical reduction of Ag NPs are... Silver nanoparticles(Ag NPs)have attracted attention in the field of biomaterials due to their excellent antibacterial property.However,the reducing and stabilizing agents used for the chemical reduction of Ag NPs are usually toxic and may cause water pollution.In this work,Ag NPs(31.2 nm in diameter)were prepared using the extract of straw,an agricultural waste,as the reducing and stabilizing agent.Experimental analysis revealed that the straw extract contained lignin,the structure of which possesses phenolic hydroxyl and methoxy groups that facilitate the reduction of silver salts into Ag NPs.The surfaces of Ag NPs were negatively charged due to the encapsulation of a thin layer of lignin molecules that prevented their aggregation.After the prepared Ag NPs were added to the precursor solution of acrylamide,free radical polymerization was triggered without the need for extra heating or light irradiation,resulting in the rapid formation of an Ag NP-polyacrylamide composite hydrogel.The inhibition zone test proved that the composite hydrogel possessed excellent antibacterial ability due to the presence of Ag NPs.The prepared hydrogel may have potential applications in the fabrication of biomedical materials,such as antibacterial dressings. 展开更多
关键词 silver nanoparticles HYDROGEL STRAW extraction ANTIBACTERIAL
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基于不同前处理方法结合全二维气相色谱飞行时间质谱解析红星二锅头白酒的风味成分 被引量:3
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作者 于立娟 田红云 +3 位作者 单群 孟士皓 冯思雨 邹弯 《食品与发酵工业》 北大核心 2025年第8期332-340,I0021-I0047,共36页
采用顶空固相微萃取(headspace solid-phase microextraction,HS-SPME)和液液萃取(liquid-liquid extraction,LLE)结合全二维气相色谱飞行时间质谱(comprehensive two-dimensional gas chromatography time of flight mass spectrometry... 采用顶空固相微萃取(headspace solid-phase microextraction,HS-SPME)和液液萃取(liquid-liquid extraction,LLE)结合全二维气相色谱飞行时间质谱(comprehensive two-dimensional gas chromatography time of flight mass spectrometry,GC×GC-TOF-MS)以及香气活度值(odour active value,OAV),对红星二锅头白酒的挥发性成分进行全面解析。研究发现,HS-SPME、LLE分别定性出928、802种挥发性化合物,共计定性出1304种挥发性化合物,共同定性出426种挥发性化合物。基于HS-SPME数据,通过香气数据库筛选出具有香气特征的382种香气化合物,其中酯类相对百分含量占比最高,其次是醇类、酸类和醛类。计算得到了49种香气化合物OAV>1,其中酯类(辛酸乙酯、异戊酸乙酯等)和萜烯类(β-大马酮)对白酒风味的贡献最大,醛类(异戊醛、己醛等)和含硫类(二甲基三硫)其次,醇类(1-辛烯-3-醇)和含氮类(2,3,5-三甲基吡嗪)也有一定风味贡献。该研究丰富了红星二锅头白酒的风味研究,也为下一步生产研究及调控提供了理论和数据支撑。 展开更多
关键词 红星二锅头白酒 全二维气相色谱飞行时间质谱(comprehensive two-dimensional gas chromatography time of flight mass spectrometry GC×GC-TOF-MS) 挥发性化合物 顶空固相微萃取(headspace solid-phase microextraction HS-SPME) 液液萃取(liquid-liquid extraction LLE)
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Review on micro-mechanism of forming emulsification during rare earth extraction by acidic extractants 被引量:2
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作者 Jie Liu Yuxiu Zhao +6 位作者 Zhirong Wang Minghui Jia Wenxiang Xia Guizhi Wu Wenda Guo Ru'an Chi Kun Huang 《Journal of Rare Earths》 2025年第1期9-20,I0001,共13页
Solvent extraction is the main method used to separate and purify rare earth elements.In the process of rare earths extraction,emulsification often generated due to the instability of the aqueous and organic phases or... Solvent extraction is the main method used to separate and purify rare earth elements.In the process of rare earths extraction,emulsification often generated due to the instability of the aqueous and organic phases or improper operating conditions.Once emulsification occurs,it would not only lead to low rare earths recovery efficiency,small product quantities,high production costs and the losing of extractant and rare earth resources,but also result in serious environmental pollution.Therefore,it is very important to study the micro-mechanisms of emulsification and establish new methods to prevent emulsification at the source.In this paper,possible factors resulting in emulsification,such as the compositions and properties of the organic and aqueous phases,the operating conditions of the rare earths extraction are reviewed.The micro-mechanisms of emulsification are summarized basing on the microscopic structures in the bulk phase,aggregations of the extractants at the organic-aqueous interface,spectral characterizations and computational simulations.On this basis,new formation mechanisms are proposed for emulsification.Preliminary explorations are employed to verify the correctness of these new viewpoints.Finally,future directions for studies of the emulsification micro-mechanism are proposed.This study provides a theoretical basis for further understanding the micro-mechanisms of interfacial instability resulting in emulsification in the process of rare earths extraction. 展开更多
关键词 Extraction Rare earths EMULSIFICATION Mechanism Interface
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Variety classification and identification of maize seeds based on hyperspectral imaging method 被引量:1
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作者 XUE Hang XU Xiping MENG Xiang 《Optoelectronics Letters》 2025年第4期234-241,共8页
In this study,eight different varieties of maize seeds were used as the research objects.Conduct 81 types of combined preprocessing on the original spectra.Through comparison,Savitzky-Golay(SG)-multivariate scattering... In this study,eight different varieties of maize seeds were used as the research objects.Conduct 81 types of combined preprocessing on the original spectra.Through comparison,Savitzky-Golay(SG)-multivariate scattering correction(MSC)-maximum-minimum normalization(MN)was identified as the optimal preprocessing technique.The competitive adaptive reweighted sampling(CARS),successive projections algorithm(SPA),and their combined methods were employed to extract feature wavelengths.Classification models based on back propagation(BP),support vector machine(SVM),random forest(RF),and partial least squares(PLS)were established using full-band data and feature wavelengths.Among all models,the(CARS-SPA)-BP model achieved the highest accuracy rate of 98.44%.This study offers novel insights and methodologies for the rapid and accurate identification of corn seeds as well as other crop seeds. 展开更多
关键词 feature extraction extract feature wavelengthsclassification models variety classification hyperspectral imaging combined preprocessing competitive adaptive reweighted sampling cars successive projections algorithm spa PREPROCESSING maize seeds
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Fresh versus frozen micro-TESE sperm and outcomes 被引量:1
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作者 Krishna Chaitanya Mantravadi Marlon Martinez +3 位作者 Favian Ariiq Rahmat Armand Achmadsyah Missy Savira Ponco Birowo 《Asian Journal of Andrology》 2025年第3期399-408,共10页
The use of fresh versus frozen spermatozoa in men with nonobstructive azoospermia (NOA) undergoingin vitro fertilization (IVF)has been a debated hot topic among reproductive specialists. Each approach presents distinc... The use of fresh versus frozen spermatozoa in men with nonobstructive azoospermia (NOA) undergoingin vitro fertilization (IVF)has been a debated hot topic among reproductive specialists. Each approach presents distinct advantages and disadvantages,with fresh sperm typically showing superior sperm quality, while frozen sperm offers logistical flexibility and a reliable backup forrepeated cycles. This review summarizes the latest advancements in sperm retrieval and cryopreservation techniques, providingpractitioners with a comprehensive analysis of each option’s strengths and limitations. Comparative studies indicate that, althoughfresh sperm often has better quality metrics, cryopreservation methods such as vitrification have significantly improved postthawoutcomes, making frozen sperm a viable choice in assisted reproductive technologies (ART). The findings show comparablerates for fertilization, implantation, clinical pregnancy, and live birth between fresh and frozen microdissection testicular spermextraction (micro-TESE) sperm in many cases, although patient-specific factors such as timing, cost-effectiveness, and proceduralconvenience should guide the final decision. Ultimately, the choice of using fresh or frozen sperm should align with the individualneeds and conditions of patients. This tailored approach, supported by the latest advancements, can optimize ART outcomes andprovide personalized reproductive care. 展开更多
关键词 CRYOPRESERVATION INFERTILITY microdissection testicular sperm extraction nonobstructive azoospermia SPERMATOZOA
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Research progress in methods of acquisition,structure elucidation,and quality control of Chinese herbal polysaccharides 被引量:1
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作者 Tingting Wang Baojie Zhu +1 位作者 Jing Zhao Shaoping Li 《Chinese Journal of Natural Medicines》 2025年第2期143-157,共15页
The therapeutic efficacy of traditional Chinese medicine has been widely acknowledged due to its extensive history of clinical effectiveness.However,the precise active components underlying each prescription remain in... The therapeutic efficacy of traditional Chinese medicine has been widely acknowledged due to its extensive history of clinical effectiveness.However,the precise active components underlying each prescription remain incompletely understood.Polysaccharides,as a major constituent of water decoctions—the most common preparation method for Chinese medicinals—may provide a crucial avenue for deepening our understanding of the efficacy principles of Chinese medicine and establishing a framework for its modern development.The structural complexity and diversity of Chinese herbal polysaccharides present significant challenges in their separation and analysis compared to small molecules.This paper aims to explore the potential of Chinese herbal polysaccharides efficiently by briefly summarizing recent advancements in polysaccharide chemical research,focusing on methods of acquisition,structure elucidation,and quality control. 展开更多
关键词 Chinese medicine POLYSACCHARIDE Extraction and purification Structural analysis Quality control
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Few-shot anomaly detection with adaptive feature transformation and descriptor construction 被引量:1
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作者 Zhengnan HU Xiangrui ZENG +4 位作者 Yiqun LI Zhouping YIN Erli MENG Leyan ZHU Xianghao KONG 《Chinese Journal of Aeronautics》 2025年第3期491-504,共14页
Anomaly Detection (AD) has been extensively adopted in industrial settings to facilitate quality control of products. It is critical to industrial production, especially to areas such as aircraft manufacturing, which ... Anomaly Detection (AD) has been extensively adopted in industrial settings to facilitate quality control of products. It is critical to industrial production, especially to areas such as aircraft manufacturing, which require strict part qualification rates. Although being more efficient and practical, few-shot AD has not been well explored. The existing AD methods only extract features in a single frequency while defects exist in multiple frequency domains. Moreover, current methods have not fully leveraged the few-shot support samples to extract input-related normal patterns. To address these issues, we propose an industrial few-shot AD method, Feature Extender for Anomaly Detection (FEAD), which extracts normal patterns in multiple frequency domains from few-shot samples under the guidance of the input sample. Firstly, to achieve better coverage of normal patterns in the input sample, we introduce a Sample-Conditioned Transformation Module (SCTM), which transforms support features under the guidance of the input sample to obtain extra normal patterns. Secondly, to effectively distinguish and localize anomaly patterns in multiple frequency domains, we devise an Adaptive Descriptor Construction Module (ADCM) to build and select pattern descriptors in a series of frequencies adaptively. Finally, an auxiliary task for SCTM is designed to ensure the diversity of transformations and include more normal patterns into support features. Extensive experiments on two widely used industrial AD datasets (MVTec-AD and VisA) demonstrate the effectiveness of the proposed FEAD. 展开更多
关键词 Industrial applications Anomaly detection Learning algorithms Feature extraction Feature selection
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Convenient and highly efficient adsorption of diosmetin from lemon peel by magnetic surface molecularly imprinted polymers 被引量:1
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作者 Dongliang Xie Yi Kuang +12 位作者 Bingnan Yuan Yunlong Zhang Chenyu Ye Yuyi Guo Hua Qiu Juanna Ren Saud O.Alshammari Qamar A.Alshammari Zeinhom M.El-Bahy Kui Zhao Zhanhu Guo Qingqing Rao Shengxiang Yang 《Journal of Materials Science & Technology》 2025年第8期159-170,共12页
As a typical bioflavonoid,diosmetin is desirable in the field of natural medicine,healthy food,and cosmetics by anti-cancer,antibacterial,antioxidant,estrogen-like and anti-inflammatory activities,and it comes from a ... As a typical bioflavonoid,diosmetin is desirable in the field of natural medicine,healthy food,and cosmetics by anti-cancer,antibacterial,antioxidant,estrogen-like and anti-inflammatory activities,and it comes from a wide range of sources in traditional Chinese medicine like spider fragrance,spearmint and chrysanthemum,as well as in Citrus fruit.However,traditional analytical methods such as silica gel column chromatography face multiple challenges in the selective extraction of diosmetin from biological materials and traditional Chinese medicinal materials.Therefore,it is urgent to develop a new type of absorbent with high efficiency,recyclability and good specificity to diosmetin.In this investigation,a magnetic surface molecularly imprinted polymer(labeled as Diosmetin/SMIPs)was synthesized employing magnetic nanoparticles as the carrier and 4-vinylpyridinyl(4-VP)as the functional monomer by surface imprinting technology.The functional monomer was screened by the binding energy(△E)between functional monomers and template molecules via computational simulation.The Diosmetin/SMIPs had a high level of specific recognition and adsorption capability towards diosmetin with a 20.25 mg g^(-1) adsorption capacity and an imprinting factor(IF)of 2.28.Additionally,it demonstrated excellent regeneration performance with 8 adsorption/desorption cycles.In addition,91.20%-94.16% of spiked diosmetin was recovered from the lemon peel samples.The strategy of constructing Diosmetin/SMIPs based on computational simulation can effectively enhance the specific adsorption performance of diosmetin.Meanwhile,Diosmetin/SMIPs synthesized by imprinting polymerization showed excellent anti-interference and reusability,and realized efficient targeted extraction of diosmetin from lemon peel samples.The results of this investigation provide a promising adsorbent for selective enrichment of diosmetin from Citrus fruit and complicated materials. 展开更多
关键词 Diosmetin Selective extraction Magnetic molecularly imprinted polymer Lemon peel
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Different extractable pools of Cd and Pb in agricultural soil under amendments:Water-soluble concentration sensitively indicates metal availability 被引量:1
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作者 Zidi Wang Wenyao Tang +8 位作者 Xiaodong Ding Qiang Dong Yingying Guo Guangliang Liu Yanwei Liu Yong Liang Yongguang Yin Yong Cai Guibin Jiang 《Journal of Environmental Sciences》 2025年第4期297-308,共12页
Identification of the most appropriate chemically extractable pool for evaluating Cd and Pb availability remains elusive,hindering accurate assessment on environmental risks and effectiveness of remediation strategies... Identification of the most appropriate chemically extractable pool for evaluating Cd and Pb availability remains elusive,hindering accurate assessment on environmental risks and effectiveness of remediation strategies.This study evaluated the feasibility of European Community Bureau of Reference(BCR)sequential extraction,Ca(NO_(3))_(2)extraction,and water extraction on assessing Cd and Pb availability in agricultural soil amended with slaked lime,magnesium hydroxide,corn stover biochar,and calcium dihydrogen phosphate.Moreover,the enriched isotope tracing technique(^(112)Cd and^(206)Pb)was employed to evaluate the aging process of newly introduced Cd and Pbwithin 56 days’incubation.Results demonstrated that extractable pools by BCR and Ca(NO_(3))_(2)extraction were little impacted by amendments and showed little correlation with soil pH.This is notable because soil pH is closely linked to metal availability,indicating these extraction methods may not adequately reflect metal availability.Conversely,water-soluble concentrations of Cd and Pb were markedly influenced by amendments and exhibited strong correlations with pH(Pearson’s r:-0.908 to-0.825,P<0.001),suggesting water extraction as a more sensitive approach.Furthermore,newly introduced metals underwent a more evident aging process as demonstrated by acid-soluble and water-soluble pools.Additionally,water-soluble concentrations of essential metals were impacted by soil amendments,raising caution on their potential effects on plant growth.These findings suggest water extraction as a promising and attractive method to evaluate Cd and Pb availability,which will help provide assessment guidance for environmental risks caused by heavy metals and develop efficient remediation strategies. 展开更多
关键词 Heavy metals Water-soluble concentrations Enriched stable isotopes Soil amendments Sequential extraction Soil pH
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Chinese satellite frequency and orbit entity relation extraction method based on dynamic integrated learning 被引量:1
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作者 Yuanzhi He Zhiqiang Li Zheng Dou 《Digital Communications and Networks》 2025年第3期787-794,共8页
Given the scarcity of Satellite Frequency and Orbit(SFO)resources,it holds paramount importance to establish a comprehensive knowledge graph of SFO field(SFO-KG)and employ knowledge reasoning technology to automatical... Given the scarcity of Satellite Frequency and Orbit(SFO)resources,it holds paramount importance to establish a comprehensive knowledge graph of SFO field(SFO-KG)and employ knowledge reasoning technology to automatically mine available SFO resources.An essential aspect of constructing SFO-KG is the extraction of Chinese entity relations.Unfortunately,there is currently no publicly available Chinese SFO entity Relation Extraction(RE)dataset.Moreover,publicly available SFO text data contain numerous NA(representing for“No Answer”)relation category sentences that resemble other relation sentences and pose challenges in accurate classification,resulting in low recall and precision for the NA relation category in entity RE.Consequently,this issue adversely affects both the accuracy of constructing the knowledge graph and the efficiency of RE processes.To address these challenges,this paper proposes a method for extracting Chinese SFO text entity relations based on dynamic integrated learning.This method includes the construction of a manually annotated Chinese SFO entity RE dataset and a classifier combining features of SFO resource data.The proposed approach combines integrated learning and pre-training models,specifically utilizing Bidirectional Encoder Representation from Transformers(BERT).In addition,it incorporates one-class classification,attention mechanisms,and dynamic feedback mechanisms to improve the performance of the RE model.Experimental results show that the proposed method outperforms the traditional methods in terms of F1 value when extracting entity relations from both balanced and long-tailed datasets. 展开更多
关键词 Knowledge graph Relation extraction One-class classification Satellite frequency and orbit resources BERT
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