Metabolomics as a research field and a set of techniques is to study the entire small molecules in biological samples.Metabolomics is emerging as a powerful tool generally for pre-cision medicine.Particularly,integrat...Metabolomics as a research field and a set of techniques is to study the entire small molecules in biological samples.Metabolomics is emerging as a powerful tool generally for pre-cision medicine.Particularly,integration of microbiome and metabolome has revealed the mechanism and functionality of microbiome in human health and disease.However,metabo-lomics data are very complicated.Preprocessing/pretreating and normalizing procedures on metabolomics data are usually required before statistical analysis.In this review article,we comprehensively review various methods that are used to preprocess and pretreat metabolo-mics data,including MS-based data and NMR-based data preprocessing,dealing with zero and/or missing values and detecting outliers,data normalization,data centering and scaling,data transformation.We discuss the advantages and limitations of each method.The choice for a suitable preprocessing method is determined by the biological hypothesis,the characteristics of the data set,and the selected statistical data analysis method.We then provide the perspective of their applications in the microbiome and metabolome research.展开更多
Lithium-ion batteries(LIBs)are the most popular energy storage devices due to their high energy density,high operating voltage,and long cycle life.However,green and effective recycling methods are needed because LIBs ...Lithium-ion batteries(LIBs)are the most popular energy storage devices due to their high energy density,high operating voltage,and long cycle life.However,green and effective recycling methods are needed because LIBs contain heavy metals such as Co,Ni,and Mn and organic compounds inside,which seriously threaten human health and the environment.In this work,we review the current status of spent LIB recycling,discuss the traditional pyrometallurgical and hydrometallurgical recovery processes,and summarize the existing short-process recovery technologies such as salt-assisted roasting,flotation processes,and direct recycling.Finally,we analyze the problems and potential research prospects of the current recycling process,and point out that the multidisciplinary integration of recycling will become the mainstream technology for the development of spent LIBs.展开更多
Surface pretreatment can change the surface properties of minerals,placing them in either a favorable or an unfavorable state for flotation.To solve the separation problem associated with magnesite and dolomite,surfac...Surface pretreatment can change the surface properties of minerals,placing them in either a favorable or an unfavorable state for flotation.To solve the separation problem associated with magnesite and dolomite,surface pretreatment experiments with citric acid,tartaric acid,and tannic acid(TA)on magnesite and dolomite as well as flotation experiments on pretreated samples were performed in this study.Experimental results demonstrated that when citric acid and tartaric acid are used for surface pretreatment,the separation effect of magnesite and dolomite is poor.However,when TA is used,the separation effect of magnesite and dolomite improves.SEM and BET analysis indicated that surface pretreatment with TA changes the surface morphology of the two minerals,resulting in additional concave pores on the dolomite surface,and a significant increase in pore size and specific surface area.The adsorption quantity test and contact angle measurement demonstrated that after surface pretreatment with TA,the magnesite adsorption capacity on sodium oleate(NaOL)slightly decreases and the dolomite adsorption capacity on NaOL considerably decreases.XPS detection concluded that the surface pretreatment of TA on the magnesite surface mainly relies on physical adsorption with weak adsorption ability and poor ability to act on Mg sites.The TA surface pretreatment action on the dolomite surface is mainly through chemical adsorption,and it is strongly and selectively adsorbed on the Ca site of dolomite through O.Actual ore rough selection experiments reveal that TA pretreatment successfully removes dolomite from magnesite,resulting in a high-quality magnesite concentrate characterized by a MgO grade of 45.49%and a CaO grade of 0.75%.展开更多
Sewage sludge in cities of Yangzi River Belt,China,generally exhibits a lower organic content and higher silt contentdue to leakage of drainage system,which caused low bioenergy recovery and carbon emission benefits i...Sewage sludge in cities of Yangzi River Belt,China,generally exhibits a lower organic content and higher silt contentdue to leakage of drainage system,which caused low bioenergy recovery and carbon emission benefits in conventional anaerobic digestion(CAD).Therefore,this paper is on a pilot scale,a bio-thermophilic pretreatment anaerobic digestion(BTPAD)for low organic sludge(volatile solids(VS)of 4%)was operated with a long-term continuous flow of 200 days.The VS degradation rate and CH_(4) yield of BTPAD increased by 19.93%and 53.33%,respectively,compared to those of CAD.The analysis of organic compositions in sludge revealed that BTPAD mainly improved the hydrolysis of proteins in sludge.Further analysis of microbial community proportions by high-throughput sequencing revealed that the short-term bio-thermophilic pretreatment was enriched in Clostridiales,Coprothermobacter and Gelria,was capable of hydrolyzing acidified proteins,and provided more volatile fatty acid(VFA)for the subsequent reaction.Biome combined with fluorescence quantitative polymerase chain reaction(PCR)analysis showed that the number of bacteria with high methanogenic capacity in BTPAD was much higher than that in CAD during the medium temperature digestion stage,indicating that short-term bio-thermophilic pretreatment could provide better methanogenic conditions for BTPAD.Furthermore,the greenhouse gas emission footprint analysis showed that short-term bio-thermophilic pretreatment could reduce the carbon emission of sludge anaerobic digestion system by 19.18%.展开更多
Oat husks,a byproduct of oat milling operations with limited economic value,present a promising feedstock for biorefinery processes due to their chemical composition.This study investigates the conversion of C5 carboh...Oat husks,a byproduct of oat milling operations with limited economic value,present a promising feedstock for biorefinery processes due to their chemical composition.This study investigates the conversion of C5 carbohydrates in oat husks into furfural through hydrothermal pretreatment using various phosphate-based catalysts,including H_(3)PO_(4),NH_(4)H_(2)PO_(4),NaH_(2)PO_(4),KH_(2)PO_(4),K_(2)HPO_(4) and K_(3)PO_(4) as catalyst.The catalysts’effectiveness in promoting furfural production was evaluated under identical hydrothermal conditions(treatment time for 60 min at a constant temperature of 170℃ and a catalyst amount).Continuous water steam was used to strip furfural from the reaction zone and minimize its degradation.Results indicated that H_(3)PO_(4) was the most effective catalyst,achieving a furfural yield of 13.99 wt.%,which corresponds to approximately 57%of the theoretical yield.NH4H2PO4 also showed moderate effectiveness,while sodium and potassium phosphate salts were significantly less effective.A scanning electron microscope analysis shows that catalysts with lower pH may disrupt the oat husks external layer thus providing a higher C5 carbohydrates conversion rate into furfural.The chemical complexity of oat husk contributes to side reactions between its carbohydrates and lignin during the hydrothermal treatment.This results in an increase in acid-insoluble lignin and inorganic matter in the oat husk lignocellulosic residue,which can reduce the effectiveness of further cellulose saccharification by enzymatic hydrolysis.展开更多
The increasing demand for sustainable energy solutions necessitates innovative approaches to biomass utilization.This study introduces a comprehensive biorefinery model that valorizes poplar biomass into high-value pr...The increasing demand for sustainable energy solutions necessitates innovative approaches to biomass utilization.This study introduces a comprehensive biorefinery model that valorizes poplar biomass into high-value products,including ethanol,furfural,phenol,and biochar.These products not only serve as promising sources for biofuel and renewable chemicals but also contribute to pollution mitigation.The approach employs a biphasic pretreatment system utilizing p-toluenesulfonic acid,pentanol,and AlCl_(3) under optimized conditions(120℃ for 45 min),achieving remarkable efficiencies of 95.8%xylan removal,90.2%delignification,and 90.7%glucan recovery.The underlying mechanism,elucidated through density functional theory,demonstrates how the disruption of lignin-carbohydrate complexes via electrostatic and hydrogen-bonding interactions enhances product yields.The cellulose-rich substrate yielded 71.3 g/L ethanol,while solubilized xylan converted to 86.7%furfural without additional acid.Furthermore,lignin pyrolysis produced bio-oil containing over 45.2%phenolic compounds,while biochar demonstrated significant adsorptive capacity for perfluorooctanoic acid.Scaling this biorefinery model to process 140 million tons of poplar biomass annually reduces CO_(2)emissions by 75.3 million tons and provides socioeconomic savings of $17.3 billion,supporting sustainable industrial transformation.展开更多
Metal oxide catalysts are widely employed in propane dehydrogenation(PDH)for propylene synthesis,requiring sequential reduction-reaction-regeneration cycles.However,the eff ect of water present in the inlet gas or rea...Metal oxide catalysts are widely employed in propane dehydrogenation(PDH)for propylene synthesis,requiring sequential reduction-reaction-regeneration cycles.However,the eff ect of water present in the inlet gas or reactor on the catalytic per-formance of various metal oxides remains insuffi ciently understood.This study examines the infl uence of water on supported metal oxide catalysts,specifi cally CoO x/Al_(2)O_(3),VO x/Al_(2)O_(3),and an industrial analog CrO x/Al_(2)O_(3) catalyst.By combining titration experiments,in situ Fourier transform infrared spectroscopy,kinetic analysis,and isotopic techniques,we demon-strate that even trace amounts of water can markedly suppress PDH performance via dissociative adsorption on the oxide surface.Methanol pretreatment eff ectively scavenges adsorbed water,recovering Lewis acid-base sites and consequently restoring PDH activity.This work underscores the profound inhibitory role of trace water in PDH over metal oxide catalysts and illustrates the potential of methanol pretreatment as an effective strategy to mitigate this limitation.展开更多
The authors regret that due to negligence,the picture was misplaced in the original manuscript,resulting in Fig.6d being incorrectly included.The correct version of Fig.6d is provided below for reference.This error do...The authors regret that due to negligence,the picture was misplaced in the original manuscript,resulting in Fig.6d being incorrectly included.The correct version of Fig.6d is provided below for reference.This error does not affect the conclusions of the study,and we apologize for any confusion it may have caused.展开更多
Hydrogen-induced cracking (HIC) is one of the most complex material problems that hydrogen can diffuse into and interact with microstructure, degrading their mechanical properties. Microstructural modification is an e...Hydrogen-induced cracking (HIC) is one of the most complex material problems that hydrogen can diffuse into and interact with microstructure, degrading their mechanical properties. Microstructural modification is an effective way to enhance the resistance to HIC. The present study focused on the relationship between the retained austenite (RA) and HIC behavior in NiCrMoV/Nb multi-alloying ultra-strength steel. Results demonstrated that the maximum volume fraction of RA of 9.31% was obtained for QL30T specimen. After the deep cryogenic pretreatment, the volume fraction of RA reduced to 8.8%. RA could reduce the effective diffusion coefficient, while deep cryogenic pretreatment increased the susceptibility of the steel to HIC by a maxim of 14.8%. This was mainly due to the transformation of retained austenite into martensite, degrading the mechanical properties under hydrogen-charged condition. In addition, the deep cryogenic pretreatment had a significant effect on the crack initiation and propagation, with the intergranular (IG) fracture becoming the dominant fracture mode where an increase in the number of secondary cracks in the section. The interfaces of RA and matrix, as well as the grain boundaries, were the preferred sites for cracks initiation.展开更多
Developing greener lignocellulose pretreatment method is one of the important issues in the biomass refining process.This work aims to investigate a recyclable Cu_(2)O/H_(2)O_(2)catalytic pretreatment method for impro...Developing greener lignocellulose pretreatment method is one of the important issues in the biomass refining process.This work aims to investigate a recyclable Cu_(2)O/H_(2)O_(2)catalytic pretreatment method for improving synthesis efficiency of aviation fuel from lignocellulosic biomass.The Cu_(2)O/H_(2)O_(2)catalytic pretreatment dramatically facilitated the preparation of ethanol intermediate and bioaviation fuel.Lignocellulosic biomass pretreated by Cu_(2)O/H_(2)O_(2)showed higher ethanol yield(33.8%).For the synthesis process of aviation fuel,ethanol conversion of 93.1%and aviation fuel selectivity of 70.8%were achieved.On the basis of catalyst characterization,biomass characterization and free radical detection,probable function and mechanism of Cu_(2)O/H_(2)O_(2)catalytic pretreatment were proposed.The cuprous oxide catalyst promoted the formation of hydroxyl radicals,thereby facilitating depolymerization of lignocellulose.Ulteriorly,Cu_(2)O/H_(2)O_(2)catalytic pretreatment enhanced the saccharification of lignocellulosic biomass,which was beneficial for the formation of ethanol intermediate and the production of biofuel.展开更多
To improve the activity of Co/Al_(2)O_(3)catalysts in selective catalytic oxidation of ammonia(NH_(3)-SCO),valence state and size of active centers of Al_(2)O_(3)-supported Co catalysts were adjusted by conducting H_(...To improve the activity of Co/Al_(2)O_(3)catalysts in selective catalytic oxidation of ammonia(NH_(3)-SCO),valence state and size of active centers of Al_(2)O_(3)-supported Co catalysts were adjusted by conducting H_(2)reduction pretreatment.The NH_(3)-SCO activity of the adjusted 2Co/Al_(2)O_(3)catalyst was substantially improved,outperforming other catalysts with higher Co-loading.Fresh Co/Al_(2)O_(3)catalysts exhibited multitemperature reduction processes,enabling the control of the valence state of the Co-active centers by adjusting the reduction temperature.Changes in the state of the Co-active centers also led to differences in redox capacity of the catalysts,resulting in different reaction mechanisms for NH_(3)-SCO.However,in situ diffuse reflectance infrared Fourier transform spectra revealed that an excessive O_(2)activation capacity caused overoxidation of NH_(3)to NO and NO_(2).The NH_(3)-SCO activity of the 2Co/Al_(2)O_(3)catalyst with low redox capacity was successfully increased while controlling and optimizing the N_(2)selectivity by modulating the active centers via H_(2)pretreatment,which is a universalmethod used for enhancing the redox properties of catalysts.Thus,this method has great potential for application in the design of inexpensive and highly active catalysts.展开更多
The ammonium salt precipitation method is frequently utilized for extracting vanadium from the leaching solution obtained through sodium roasting of vanadium slag.However,Na^(+)and NH_(4)^(+)ions in the vanadium preci...The ammonium salt precipitation method is frequently utilized for extracting vanadium from the leaching solution obtained through sodium roasting of vanadium slag.However,Na^(+)and NH_(4)^(+)ions in the vanadium precipitation solution can not be effectively separated,leading to a large amount of ammonia-nitrogen wastewater which is difficult to treat.In this study,the manganese salt pretreatment process is used to extract vanadium from a sodium roasting leaching solution,enabling the separation of vanadium and sodium.The vanadium extraction product of manganese salt is dissolved in acid to obtain vanadium-containing leaching solution,then vanadium is extracted by hydrolysis and vanadium precipitation,and V_(2)O_(5)is obtained after impurity removal and calcination.The results show that the rate of vanadium extraction by manganese salt is 98.23%.The vanadium extraction product by manganese salt is Mn_(2)V_(2)O_(7),and its sodium content is only 0.167%.Additionally,the acid solubility of vanadium extraction products by manganese salt is 99.52%,and the vanadium precipitation rate of manganese vanadate solution is 92.34%.After the removal of manganese and calcination process,the purity of V_(2)O_(5)product reached 97.73%,with a mere 0.64%loss of vanadium.The Mn_(2)^(+)and NH_(4)^(+)ions in the solution after vanadium precipitation are separated by precipitation method,which reduces the generation of ammonia-nitrogen wastewater.This is conducive to the green and sustainable development of the vanadium industry.展开更多
[ Objective] The aim was to study pretreatment of ultrasound enhancing dilute H2SO4 on cellulase activity of corn straw liquid fermentation and explore the pretretment＇ s optimal conditions. [ Method ] By using ortho...[ Objective] The aim was to study pretreatment of ultrasound enhancing dilute H2SO4 on cellulase activity of corn straw liquid fermentation and explore the pretretment＇ s optimal conditions. [ Method ] By using orthogonal test, the pretretment of ultrasound enhancing dilute H2SO4 on corn straw was studied, then straw was fermented as the sole carbon source. Finally, the cellulase activity in extracellular fermentation broth was determined. [Result] The results showed that cellulase activity in extracellular broth was greatest under the conditions of acid bath time 3 h, acid concentration 3.5%, ultrasonic power 150 W, and ultrasonic time 5 h. They were FPA 15.82 U/ml, Cx 39.9 U/ml, 13-Giu 55.94 U/ml respectively. [ Conclusion] Under the above conditions, extracellular cellulase production has a high stability.展开更多
Pretreated Mg-Li alloy sheets were pre-plated in a NiCO3？2Ni（OH）2？4H2O solution to form a thin Ni-P alloy film and then plating in a NiSO4？6H2O solution was carried out to obtain a protective coating.The surface ...Pretreated Mg-Li alloy sheets were pre-plated in a NiCO3？2Ni（OH）2？4H2O solution to form a thin Ni-P alloy film and then plating in a NiSO4？6H2O solution was carried out to obtain a protective coating.The surface morphology,structure and corrosion resistance of the coating were studied.The results showed that a flat,bright and compact plating layer,which was integrated into the matrix metal,was obtained.The P content of the Ni-P coating reached 13.56%（mass fraction）.The hardness value of the Ni-P coating was about HV 549.The polarization curve showed that the corrosion potential of the Ni-P coating reached ？0.249 V（vs SCE）.A long passivation region was found on the polarization curve,and this phenomenon indicated that the coating has an excellent anti-corrosion property.展开更多
Carbonaceous gold mines are important refractory gold ores. The previous results demonstrate that the carbonaceous matter is mainly composed of elemental carbon, organic acid and hydrocarbons. The dissolved aurocyanid...Carbonaceous gold mines are important refractory gold ores. The previous results demonstrate that the carbonaceous matter is mainly composed of elemental carbon, organic acid and hydrocarbons. The dissolved aurocyanide complex is robbed by adsorption of carbonaceous matter, which is similar to activated carbon in cyanide leaching of gold. The pretreatment methods of carbonaceous gold ores were introduced, including high temperature roasting, bio-oxidation, chemical oxidation, competitive adsorption, barrier inhibition and microwave roasting. Recently, bio-oxidation was developed rapidly due to its advantages such as mild conditions, simple processes, low energy consumption and friendly environment. The known microorganisms related with bio-oxidation pretreatment mainly are chemolithotroph bacteria such as Thiobacillus ferrooxidans, Thiobacillus thiooxidans and Leptospirillum ferrooxidans. The researches on decomposing and passivating carbonaceous matter were commenced by Phanerochaete chrysosporium, Pseudomonadaceae and Streptomyces setonii. Finally, the main problems were analyzed and the application prospect of this technique was looked forward.展开更多
It is difficult to directly electroplate Al on Mg alloys. The effects of pretreatment parameters on the corrosion resistance of films obtained on AZ31 Mg alloy surface were studied by using potentiodynamic polarizatio...It is difficult to directly electroplate Al on Mg alloys. The effects of pretreatment parameters on the corrosion resistance of films obtained on AZ31 Mg alloy surface were studied by using potentiodynamic polarization curves, to produce a compact interfacial layer as zinc-immersion deposition. After the substrate was pretreated under optimized conditions, aluminum was electrodeposited on AZ31 from TMPAC-AlCl3 room temperature ionic liquids. The depositions were characterized by scanning electron microscope equipped with energy dispersion X-ray. The results show that the traditional pretreatment of Mg alloys was successfully used for the Al-electroplating process from TMPAC-AlCl3 ionic liquids. The entire procedure includes alkaline cleaning, chemical pickling, surface activation （400 mL/L HF acid, 10 min）, zinc-immersion （20 min） and anhydrous treatment. A relatively compact zinc-immersion film was prepared on the substrate surface. A silvery-colored satin aluminum deposition was obtained on AZ31 from TMPAC-AlCl3 using direct current plating.展开更多
A novel process was proposed for the activation pretreatment of limonitic laterite ores by Na2CO3 roasting. Dechromization and dealumination kinetics of the laterite ores and the effect of particle size, Na2CO3-ore ma...A novel process was proposed for the activation pretreatment of limonitic laterite ores by Na2CO3 roasting. Dechromization and dealumination kinetics of the laterite ores and the effect of particle size, Na2CO3-ore mass ratio, and roasting temperature on Cr and Al extraction were studied. Experimental results indicate that the extraction rates of Cr and Al are up to 99%and 82%, respectively, under the optimal particle size of 44–74μm, Na2CO3-to-ore mass ratio of 0.6：1, and temperature of 1000 ℃. Dechromization within the range of 600–800 oC is controlled by the diffusion through the product layer with an apparent activation energy of 3.9 kJ/mol, and that it is controlled by the chemical reaction at the surface within the range of 900–1100 ℃ with an apparent activation energy of 54.3 kJ/mol. Besides, the Avrami diffusion controlled model with on apparent activation energy of 16.4 kJ/mol is most applicable for dealumination. Furthermore, 96.8%Ni and 95.6%Co could be extracted from the alkali-roasting residues in the subsequent pressure acid leaching process.展开更多
[ Objective] To study the effects of different pretreatment methods on determination of microelement in feed and thus find the best pre treatment method for each microetement, t Method] The samples （concentrated feed...[ Objective] To study the effects of different pretreatment methods on determination of microelement in feed and thus find the best pre treatment method for each microetement, t Method] The samples （concentrated feeding stuff and fodder） were pretreated through throe methods, that is, dry incineration method, HNOs HCIO, wetdecomposition method and microwave digestion method. Then the content of seven kinds of mi croelement （AI, Ca, Cu, Fe, Mn, Se and Zn） was determined by inductively coupled plasma atomic emission spectrometer （ICPAES）. I Result] These three methods were all suitable for the determination of Cu, Mn and Zn in concentrated feeding stuff and the determination of Cu and Ca in fodder. The content of Cu and Ca was higher in fodder detected by HNO3 HCIO, wetdecomposition method. The microwave digestion method was suitable for the determination of AI and Ca in concentrated feeding stuff and the determination of AI, Fe, Mn and Zn in fodder. The dry incinera tion method was fit for the determination of Fe in concentrated feeding stuff. [ Condusionl The content of different microelements should be deter mined after the feed is treated with different Ioretreatment methods.展开更多
Immunoassay technology is an analytical method with high sensitivity and specificity; it provides a technique to assay materials which cannot be measured by other methods, or are difficult to detect. It plays a very i...Immunoassay technology is an analytical method with high sensitivity and specificity; it provides a technique to assay materials which cannot be measured by other methods, or are difficult to detect. It plays a very important role in biological sample pre-treatment, therapeutic drug monitoring and drug determination, and is one of the important means for in vivo drug analyses. This paper reviews immunoassays commonly used in bioanalysis, including immunoextraction and immunodepletion for pretreatment of biological samples, conventional immunoassay methods and new immunoassay technologies for determination of target drugs.展开更多
Pretreatment on vegetable and fruit is a key chain of drying process. The research analyzed mechanisms and applications of different pretreatments such as blanching, freezing, liquid glucose pretreatment, NaCI dipping...Pretreatment on vegetable and fruit is a key chain of drying process. The research analyzed mechanisms and applications of different pretreatments such as blanching, freezing, liquid glucose pretreatment, NaCI dipping, and high-voltage elec- tric field, and proposed the development prospect.展开更多
基金supported by the Crohn's&Colitis Foundation Senior Research Award(No.902766 to J.S.)The National Institute of Diabetes and Digestive and Kidney Diseases(No.R01DK105118-01 and R01DK114126 to J.S.)+1 种基金United States Department of Defense Congressionally Directed Medical Research Programs(No.BC191198 to J.S.)VA Merit Award BX-19-00 to J.S.
文摘Metabolomics as a research field and a set of techniques is to study the entire small molecules in biological samples.Metabolomics is emerging as a powerful tool generally for pre-cision medicine.Particularly,integration of microbiome and metabolome has revealed the mechanism and functionality of microbiome in human health and disease.However,metabo-lomics data are very complicated.Preprocessing/pretreating and normalizing procedures on metabolomics data are usually required before statistical analysis.In this review article,we comprehensively review various methods that are used to preprocess and pretreat metabolo-mics data,including MS-based data and NMR-based data preprocessing,dealing with zero and/or missing values and detecting outliers,data normalization,data centering and scaling,data transformation.We discuss the advantages and limitations of each method.The choice for a suitable preprocessing method is determined by the biological hypothesis,the characteristics of the data set,and the selected statistical data analysis method.We then provide the perspective of their applications in the microbiome and metabolome research.
基金financial support by the National Natural Science Foundation of China(No.52374293)Zhongyuan Science and Technology Innovation Leading Talent Project,China(No.224200510025)+1 种基金the Science and Technology Innovation Program of Hunan Province,China(No.2022RC1123)One of the authors,Hong-bo ZENG,gratefully acknowledges the support from the Natural Sciences and Engineering Research Council of Canada(NSERC)and the Canada Research Chairs Program.
文摘Lithium-ion batteries(LIBs)are the most popular energy storage devices due to their high energy density,high operating voltage,and long cycle life.However,green and effective recycling methods are needed because LIBs contain heavy metals such as Co,Ni,and Mn and organic compounds inside,which seriously threaten human health and the environment.In this work,we review the current status of spent LIB recycling,discuss the traditional pyrometallurgical and hydrometallurgical recovery processes,and summarize the existing short-process recovery technologies such as salt-assisted roasting,flotation processes,and direct recycling.Finally,we analyze the problems and potential research prospects of the current recycling process,and point out that the multidisciplinary integration of recycling will become the mainstream technology for the development of spent LIBs.
基金Project(BGRIMM-KJSKL-2024-07) supported by the Open Foundation of State Key Laboratory of Mineral Processing,ChinaProjects(52374259,52174239) supported by the National Natural Science Foundation of China。
文摘Surface pretreatment can change the surface properties of minerals,placing them in either a favorable or an unfavorable state for flotation.To solve the separation problem associated with magnesite and dolomite,surface pretreatment experiments with citric acid,tartaric acid,and tannic acid(TA)on magnesite and dolomite as well as flotation experiments on pretreated samples were performed in this study.Experimental results demonstrated that when citric acid and tartaric acid are used for surface pretreatment,the separation effect of magnesite and dolomite is poor.However,when TA is used,the separation effect of magnesite and dolomite improves.SEM and BET analysis indicated that surface pretreatment with TA changes the surface morphology of the two minerals,resulting in additional concave pores on the dolomite surface,and a significant increase in pore size and specific surface area.The adsorption quantity test and contact angle measurement demonstrated that after surface pretreatment with TA,the magnesite adsorption capacity on sodium oleate(NaOL)slightly decreases and the dolomite adsorption capacity on NaOL considerably decreases.XPS detection concluded that the surface pretreatment of TA on the magnesite surface mainly relies on physical adsorption with weak adsorption ability and poor ability to act on Mg sites.The TA surface pretreatment action on the dolomite surface is mainly through chemical adsorption,and it is strongly and selectively adsorbed on the Ca site of dolomite through O.Actual ore rough selection experiments reveal that TA pretreatment successfully removes dolomite from magnesite,resulting in a high-quality magnesite concentrate characterized by a MgO grade of 45.49%and a CaO grade of 0.75%.
基金supported by the National Key Research and Development Project (Nos.2020YFC1908702 and 2021YFC3200700)the National Natural Science Foundation of China (Nos.52192684 and 52192680).
文摘Sewage sludge in cities of Yangzi River Belt,China,generally exhibits a lower organic content and higher silt contentdue to leakage of drainage system,which caused low bioenergy recovery and carbon emission benefits in conventional anaerobic digestion(CAD).Therefore,this paper is on a pilot scale,a bio-thermophilic pretreatment anaerobic digestion(BTPAD)for low organic sludge(volatile solids(VS)of 4%)was operated with a long-term continuous flow of 200 days.The VS degradation rate and CH_(4) yield of BTPAD increased by 19.93%and 53.33%,respectively,compared to those of CAD.The analysis of organic compositions in sludge revealed that BTPAD mainly improved the hydrolysis of proteins in sludge.Further analysis of microbial community proportions by high-throughput sequencing revealed that the short-term bio-thermophilic pretreatment was enriched in Clostridiales,Coprothermobacter and Gelria,was capable of hydrolyzing acidified proteins,and provided more volatile fatty acid(VFA)for the subsequent reaction.Biome combined with fluorescence quantitative polymerase chain reaction(PCR)analysis showed that the number of bacteria with high methanogenic capacity in BTPAD was much higher than that in CAD during the medium temperature digestion stage,indicating that short-term bio-thermophilic pretreatment could provide better methanogenic conditions for BTPAD.Furthermore,the greenhouse gas emission footprint analysis showed that short-term bio-thermophilic pretreatment could reduce the carbon emission of sludge anaerobic digestion system by 19.18%.
基金funded by the Latvian State Institute of Wood Chemistry Bioeconomic Research Grant No.09-24 titled“Selective Valorization of Lignocellulosic Biomass(SeVaLi)”.
文摘Oat husks,a byproduct of oat milling operations with limited economic value,present a promising feedstock for biorefinery processes due to their chemical composition.This study investigates the conversion of C5 carbohydrates in oat husks into furfural through hydrothermal pretreatment using various phosphate-based catalysts,including H_(3)PO_(4),NH_(4)H_(2)PO_(4),NaH_(2)PO_(4),KH_(2)PO_(4),K_(2)HPO_(4) and K_(3)PO_(4) as catalyst.The catalysts’effectiveness in promoting furfural production was evaluated under identical hydrothermal conditions(treatment time for 60 min at a constant temperature of 170℃ and a catalyst amount).Continuous water steam was used to strip furfural from the reaction zone and minimize its degradation.Results indicated that H_(3)PO_(4) was the most effective catalyst,achieving a furfural yield of 13.99 wt.%,which corresponds to approximately 57%of the theoretical yield.NH4H2PO4 also showed moderate effectiveness,while sodium and potassium phosphate salts were significantly less effective.A scanning electron microscope analysis shows that catalysts with lower pH may disrupt the oat husks external layer thus providing a higher C5 carbohydrates conversion rate into furfural.The chemical complexity of oat husk contributes to side reactions between its carbohydrates and lignin during the hydrothermal treatment.This results in an increase in acid-insoluble lignin and inorganic matter in the oat husk lignocellulosic residue,which can reduce the effectiveness of further cellulose saccharification by enzymatic hydrolysis.
基金funded by the National Natural Science Foundation of China(22278189,22478154)the Fundamental Research Funds for the Central Universities(Jiangnan University,JUSRP202501024)the Priority Academic Program Development of Jiangsu Higher Education Institutions,the 111 Project(No.111-2-06)。
文摘The increasing demand for sustainable energy solutions necessitates innovative approaches to biomass utilization.This study introduces a comprehensive biorefinery model that valorizes poplar biomass into high-value products,including ethanol,furfural,phenol,and biochar.These products not only serve as promising sources for biofuel and renewable chemicals but also contribute to pollution mitigation.The approach employs a biphasic pretreatment system utilizing p-toluenesulfonic acid,pentanol,and AlCl_(3) under optimized conditions(120℃ for 45 min),achieving remarkable efficiencies of 95.8%xylan removal,90.2%delignification,and 90.7%glucan recovery.The underlying mechanism,elucidated through density functional theory,demonstrates how the disruption of lignin-carbohydrate complexes via electrostatic and hydrogen-bonding interactions enhances product yields.The cellulose-rich substrate yielded 71.3 g/L ethanol,while solubilized xylan converted to 86.7%furfural without additional acid.Furthermore,lignin pyrolysis produced bio-oil containing over 45.2%phenolic compounds,while biochar demonstrated significant adsorptive capacity for perfluorooctanoic acid.Scaling this biorefinery model to process 140 million tons of poplar biomass annually reduces CO_(2)emissions by 75.3 million tons and provides socioeconomic savings of $17.3 billion,supporting sustainable industrial transformation.
基金supported by the National Key R&D Program of China(No.2023YFA1507800)the National Science Foundation of China(Nos.22121004,22122808,22478279,and 22108201)+1 种基金the Haihe Laboratory of Sustainable Chemical Trans-formations,the Program of Introducing Talents of Discipline to Uni-versities(No.BP0618007)the XPLORER PRIZE.
文摘Metal oxide catalysts are widely employed in propane dehydrogenation(PDH)for propylene synthesis,requiring sequential reduction-reaction-regeneration cycles.However,the eff ect of water present in the inlet gas or reactor on the catalytic per-formance of various metal oxides remains insuffi ciently understood.This study examines the infl uence of water on supported metal oxide catalysts,specifi cally CoO x/Al_(2)O_(3),VO x/Al_(2)O_(3),and an industrial analog CrO x/Al_(2)O_(3) catalyst.By combining titration experiments,in situ Fourier transform infrared spectroscopy,kinetic analysis,and isotopic techniques,we demon-strate that even trace amounts of water can markedly suppress PDH performance via dissociative adsorption on the oxide surface.Methanol pretreatment eff ectively scavenges adsorbed water,recovering Lewis acid-base sites and consequently restoring PDH activity.This work underscores the profound inhibitory role of trace water in PDH over metal oxide catalysts and illustrates the potential of methanol pretreatment as an effective strategy to mitigate this limitation.
文摘The authors regret that due to negligence,the picture was misplaced in the original manuscript,resulting in Fig.6d being incorrectly included.The correct version of Fig.6d is provided below for reference.This error does not affect the conclusions of the study,and we apologize for any confusion it may have caused.
文摘Hydrogen-induced cracking (HIC) is one of the most complex material problems that hydrogen can diffuse into and interact with microstructure, degrading their mechanical properties. Microstructural modification is an effective way to enhance the resistance to HIC. The present study focused on the relationship between the retained austenite (RA) and HIC behavior in NiCrMoV/Nb multi-alloying ultra-strength steel. Results demonstrated that the maximum volume fraction of RA of 9.31% was obtained for QL30T specimen. After the deep cryogenic pretreatment, the volume fraction of RA reduced to 8.8%. RA could reduce the effective diffusion coefficient, while deep cryogenic pretreatment increased the susceptibility of the steel to HIC by a maxim of 14.8%. This was mainly due to the transformation of retained austenite into martensite, degrading the mechanical properties under hydrogen-charged condition. In addition, the deep cryogenic pretreatment had a significant effect on the crack initiation and propagation, with the intergranular (IG) fracture becoming the dominant fracture mode where an increase in the number of secondary cracks in the section. The interfaces of RA and matrix, as well as the grain boundaries, were the preferred sites for cracks initiation.
基金supported by the National Natural Science Foundation of China(No.U21A20288)。
文摘Developing greener lignocellulose pretreatment method is one of the important issues in the biomass refining process.This work aims to investigate a recyclable Cu_(2)O/H_(2)O_(2)catalytic pretreatment method for improving synthesis efficiency of aviation fuel from lignocellulosic biomass.The Cu_(2)O/H_(2)O_(2)catalytic pretreatment dramatically facilitated the preparation of ethanol intermediate and bioaviation fuel.Lignocellulosic biomass pretreated by Cu_(2)O/H_(2)O_(2)showed higher ethanol yield(33.8%).For the synthesis process of aviation fuel,ethanol conversion of 93.1%and aviation fuel selectivity of 70.8%were achieved.On the basis of catalyst characterization,biomass characterization and free radical detection,probable function and mechanism of Cu_(2)O/H_(2)O_(2)catalytic pretreatment were proposed.The cuprous oxide catalyst promoted the formation of hydroxyl radicals,thereby facilitating depolymerization of lignocellulose.Ulteriorly,Cu_(2)O/H_(2)O_(2)catalytic pretreatment enhanced the saccharification of lignocellulosic biomass,which was beneficial for the formation of ethanol intermediate and the production of biofuel.
基金supported by the National Natural Science Foundation of China(No.52260013)Yunnan Major Scientific and Technological Projects(No.202202AG050005).
文摘To improve the activity of Co/Al_(2)O_(3)catalysts in selective catalytic oxidation of ammonia(NH_(3)-SCO),valence state and size of active centers of Al_(2)O_(3)-supported Co catalysts were adjusted by conducting H_(2)reduction pretreatment.The NH_(3)-SCO activity of the adjusted 2Co/Al_(2)O_(3)catalyst was substantially improved,outperforming other catalysts with higher Co-loading.Fresh Co/Al_(2)O_(3)catalysts exhibited multitemperature reduction processes,enabling the control of the valence state of the Co-active centers by adjusting the reduction temperature.Changes in the state of the Co-active centers also led to differences in redox capacity of the catalysts,resulting in different reaction mechanisms for NH_(3)-SCO.However,in situ diffuse reflectance infrared Fourier transform spectra revealed that an excessive O_(2)activation capacity caused overoxidation of NH_(3)to NO and NO_(2).The NH_(3)-SCO activity of the 2Co/Al_(2)O_(3)catalyst with low redox capacity was successfully increased while controlling and optimizing the N_(2)selectivity by modulating the active centers via H_(2)pretreatment,which is a universalmethod used for enhancing the redox properties of catalysts.Thus,this method has great potential for application in the design of inexpensive and highly active catalysts.
基金supported by the National Natural Science Foundation of China(52204309,52374300 and 52174277)the Opening Foundation of State Key Laboratory of Vanadium and Titanium Resources Comprehensive Utilization,China(2022P4FZG11A).
文摘The ammonium salt precipitation method is frequently utilized for extracting vanadium from the leaching solution obtained through sodium roasting of vanadium slag.However,Na^(+)and NH_(4)^(+)ions in the vanadium precipitation solution can not be effectively separated,leading to a large amount of ammonia-nitrogen wastewater which is difficult to treat.In this study,the manganese salt pretreatment process is used to extract vanadium from a sodium roasting leaching solution,enabling the separation of vanadium and sodium.The vanadium extraction product of manganese salt is dissolved in acid to obtain vanadium-containing leaching solution,then vanadium is extracted by hydrolysis and vanadium precipitation,and V_(2)O_(5)is obtained after impurity removal and calcination.The results show that the rate of vanadium extraction by manganese salt is 98.23%.The vanadium extraction product by manganese salt is Mn_(2)V_(2)O_(7),and its sodium content is only 0.167%.Additionally,the acid solubility of vanadium extraction products by manganese salt is 99.52%,and the vanadium precipitation rate of manganese vanadate solution is 92.34%.After the removal of manganese and calcination process,the purity of V_(2)O_(5)product reached 97.73%,with a mere 0.64%loss of vanadium.The Mn_(2)^(+)and NH_(4)^(+)ions in the solution after vanadium precipitation are separated by precipitation method,which reduces the generation of ammonia-nitrogen wastewater.This is conducive to the green and sustainable development of the vanadium industry.
基金Supported by the National Key Technology R&D Program during the11~(th)five-year Plan(2007BAD34B03)the Important Project of Ministryof Education(107127)Scientific Research Foundation ofHefei University of Technology(113-036404)~~
文摘[ Objective] The aim was to study pretreatment of ultrasound enhancing dilute H2SO4 on cellulase activity of corn straw liquid fermentation and explore the pretretment＇ s optimal conditions. [ Method ] By using orthogonal test, the pretretment of ultrasound enhancing dilute H2SO4 on corn straw was studied, then straw was fermented as the sole carbon source. Finally, the cellulase activity in extracellular fermentation broth was determined. [Result] The results showed that cellulase activity in extracellular broth was greatest under the conditions of acid bath time 3 h, acid concentration 3.5%, ultrasonic power 150 W, and ultrasonic time 5 h. They were FPA 15.82 U/ml, Cx 39.9 U/ml, 13-Giu 55.94 U/ml respectively. [ Conclusion] Under the above conditions, extracellular cellulase production has a high stability.
基金Projects(50974114,51174060) supported by National Natural Science Foundation of ChinaProject(2008AA03Z512) supported by High-tech Research and Development Program of ChinaProject(20070145049) supported by PhD Programs Foundation of Ministry of Education of China
文摘Pretreated Mg-Li alloy sheets were pre-plated in a NiCO3？2Ni（OH）2？4H2O solution to form a thin Ni-P alloy film and then plating in a NiSO4？6H2O solution was carried out to obtain a protective coating.The surface morphology,structure and corrosion resistance of the coating were studied.The results showed that a flat,bright and compact plating layer,which was integrated into the matrix metal,was obtained.The P content of the Ni-P coating reached 13.56%（mass fraction）.The hardness value of the Ni-P coating was about HV 549.The polarization curve showed that the corrosion potential of the Ni-P coating reached ？0.249 V（vs SCE）.A long passivation region was found on the polarization curve,and this phenomenon indicated that the coating has an excellent anti-corrosion property.
基金Projects(51174062,51104036)supported by the National Natural Science Foundation of ChinaProject(2012BAE06B05)supported by the National Science and Technology Support Program of China during the 12th Five-Year Plan Period+1 种基金Projects(2012AA061502,2012AA061501)supported by the National High-Tech Research and Development Program of ChinaProjects(N120602006,N110302002,N110602005)supported by Fundamental Research Funds for the Central Universities of China
文摘Carbonaceous gold mines are important refractory gold ores. The previous results demonstrate that the carbonaceous matter is mainly composed of elemental carbon, organic acid and hydrocarbons. The dissolved aurocyanide complex is robbed by adsorption of carbonaceous matter, which is similar to activated carbon in cyanide leaching of gold. The pretreatment methods of carbonaceous gold ores were introduced, including high temperature roasting, bio-oxidation, chemical oxidation, competitive adsorption, barrier inhibition and microwave roasting. Recently, bio-oxidation was developed rapidly due to its advantages such as mild conditions, simple processes, low energy consumption and friendly environment. The known microorganisms related with bio-oxidation pretreatment mainly are chemolithotroph bacteria such as Thiobacillus ferrooxidans, Thiobacillus thiooxidans and Leptospirillum ferrooxidans. The researches on decomposing and passivating carbonaceous matter were commenced by Phanerochaete chrysosporium, Pseudomonadaceae and Streptomyces setonii. Finally, the main problems were analyzed and the application prospect of this technique was looked forward.
文摘It is difficult to directly electroplate Al on Mg alloys. The effects of pretreatment parameters on the corrosion resistance of films obtained on AZ31 Mg alloy surface were studied by using potentiodynamic polarization curves, to produce a compact interfacial layer as zinc-immersion deposition. After the substrate was pretreated under optimized conditions, aluminum was electrodeposited on AZ31 from TMPAC-AlCl3 room temperature ionic liquids. The depositions were characterized by scanning electron microscope equipped with energy dispersion X-ray. The results show that the traditional pretreatment of Mg alloys was successfully used for the Al-electroplating process from TMPAC-AlCl3 ionic liquids. The entire procedure includes alkaline cleaning, chemical pickling, surface activation （400 mL/L HF acid, 10 min）, zinc-immersion （20 min） and anhydrous treatment. A relatively compact zinc-immersion film was prepared on the substrate surface. A silvery-colored satin aluminum deposition was obtained on AZ31 from TMPAC-AlCl3 using direct current plating.
基金Project(51125018)supported by the National Natural Science Foundation for Distinguished Young Scholars of ChinaProject(51204153)supported by the National Natural Science Foundation of ChinaProject(2011BAC06B07)supported by the National High Technology Research and Development Program,China
文摘A novel process was proposed for the activation pretreatment of limonitic laterite ores by Na2CO3 roasting. Dechromization and dealumination kinetics of the laterite ores and the effect of particle size, Na2CO3-ore mass ratio, and roasting temperature on Cr and Al extraction were studied. Experimental results indicate that the extraction rates of Cr and Al are up to 99%and 82%, respectively, under the optimal particle size of 44–74μm, Na2CO3-to-ore mass ratio of 0.6：1, and temperature of 1000 ℃. Dechromization within the range of 600–800 oC is controlled by the diffusion through the product layer with an apparent activation energy of 3.9 kJ/mol, and that it is controlled by the chemical reaction at the surface within the range of 900–1100 ℃ with an apparent activation energy of 54.3 kJ/mol. Besides, the Avrami diffusion controlled model with on apparent activation energy of 16.4 kJ/mol is most applicable for dealumination. Furthermore, 96.8%Ni and 95.6%Co could be extracted from the alkali-roasting residues in the subsequent pressure acid leaching process.
文摘[ Objective] To study the effects of different pretreatment methods on determination of microelement in feed and thus find the best pre treatment method for each microetement, t Method] The samples （concentrated feeding stuff and fodder） were pretreated through throe methods, that is, dry incineration method, HNOs HCIO, wetdecomposition method and microwave digestion method. Then the content of seven kinds of mi croelement （AI, Ca, Cu, Fe, Mn, Se and Zn） was determined by inductively coupled plasma atomic emission spectrometer （ICPAES）. I Result] These three methods were all suitable for the determination of Cu, Mn and Zn in concentrated feeding stuff and the determination of Cu and Ca in fodder. The content of Cu and Ca was higher in fodder detected by HNO3 HCIO, wetdecomposition method. The microwave digestion method was suitable for the determination of AI and Ca in concentrated feeding stuff and the determination of AI, Fe, Mn and Zn in fodder. The dry incinera tion method was fit for the determination of Fe in concentrated feeding stuff. [ Condusionl The content of different microelements should be deter mined after the feed is treated with different Ioretreatment methods.
基金National Natural Science Foundation of China(Gr ant No.81102499)Hunan Science and Technology Project(Grant No.2011SK3261)
文摘Immunoassay technology is an analytical method with high sensitivity and specificity; it provides a technique to assay materials which cannot be measured by other methods, or are difficult to detect. It plays a very important role in biological sample pre-treatment, therapeutic drug monitoring and drug determination, and is one of the important means for in vivo drug analyses. This paper reviews immunoassays commonly used in bioanalysis, including immunoextraction and immunodepletion for pretreatment of biological samples, conventional immunoassay methods and new immunoassay technologies for determination of target drugs.
基金Supported by National Natural Science Foundation of China(31360399)~~
文摘Pretreatment on vegetable and fruit is a key chain of drying process. The research analyzed mechanisms and applications of different pretreatments such as blanching, freezing, liquid glucose pretreatment, NaCI dipping, and high-voltage elec- tric field, and proposed the development prospect.
