Cellulosic ethanol involves the following production steps: physical and/or chemical pretreatment, biological treatment, fermentation and distillation. First three steps are also the bottlenecks for the production of ...Cellulosic ethanol involves the following production steps: physical and/or chemical pretreatment, biological treatment, fermentation and distillation. First three steps are also the bottlenecks for the production of cellulosic ethanol and its co-products. Their production still pose some difficulties in terms of pretreatment, the high cost of enzymes for substrate hydrolysis, the formation of inhibitory compounds in the hydrolyzate, the lack of efficient and viable microorganisms for industrial fermentation of hexose and pentose among others. The solution or minimization of these difficulties may lead to numerous socio-environmental, political, and economic advantages for cellulosic ethanol production. This paper highlights the potential of different substrates, pretreatments, microorganisms and bioprocesses for cellulosic ethanol production.展开更多
In this editorial,we offer our perspective on the groundbreaking study entitled“Hypoxia and inflammatory factor preconditioning enhances the immunosup-pressive properties of human umbilical cord mesenchymal stem cell...In this editorial,we offer our perspective on the groundbreaking study entitled“Hypoxia and inflammatory factor preconditioning enhances the immunosup-pressive properties of human umbilical cord mesenchymal stem cells”,recently published in World Journal of Stem Cells.Despite over three decades of research on the clinical application of mesenchymal stem cells(MSCs),only a few therapeutic products have made it to clinical use,due to multiple preclinical and clinical challenges yet to be addressed.The study proved the hypoxia and inflammatory factor preconditioning led to higher immunosuppressive effects of MSCs without damaging their biological characteristics,which revealed the combination of inflammatory factors and hypoxic preconditioning offers a promising approach to enhance the function of MSCs.As we delve deeper into the intricacies of pretreat-ment methodologies,we anticipate a transformative shift in the landscape of MSC-based therapies,ultimately contributing to improved patient outcomes and advancing the field as a whole.展开更多
This study investigated a combined low-thermal and CaO_(2)pretreatment to enhance the volatile fatty acid(VFA)production from waste activated sludge(WAS).The fermentative product was added to a sequencing batch reacto...This study investigated a combined low-thermal and CaO_(2)pretreatment to enhance the volatile fatty acid(VFA)production from waste activated sludge(WAS).The fermentative product was added to a sequencing batch reactor(SBR)as an external carbon source to enhance nitrogen removal.The results showed that the combined pretreatment improved WAS solubilization,releasing more biodegradable substrates,such as proteins and polysaccharides,from TB-EPS to LB-EPS and S-EPS.The maximum VFA production of 3529±188 mg COD/L was obtained in the combined pretreatment(0.2 g CaO_(2)/g VS+70℃for 60 min),which was 2.1 and 1.4-fold of that obtained from the sole low-thermal pretreatment and the control test,respectively.Consequently,when the fermentative liquid was added as an external denitrification carbon source,the effluent total nitrogen decreased to Class A of the discharge standard for pollutants in rural wastewater treatment plants in most areas of China.展开更多
This paper studies the influence of three different pretreatments( blanching,citric acid soaking,and Na Cl soaking) on the moisture content,degree of puffing,color,hardness and crispness of Hami melon under explosion ...This paper studies the influence of three different pretreatments( blanching,citric acid soaking,and Na Cl soaking) on the moisture content,degree of puffing,color,hardness and crispness of Hami melon under explosion puffing drying at modified temperature and pressure in Xinjiang. The results show that using 60 s blanching pretreatment can help to reduce the moisture content of puffed product while maintaining product color; 2. 5% citric acid pretreatment can make products maintain high degree of puffing and crispness,but reduce product color; 2%Na Cl penetrating fluid plays a significant role in maintaining product color,while maintaining crispness.展开更多
Hemp fibers were treated with different pretreatments before being put into ionic liquid dissolved systems. NaOH,HCI,N,N-dimethylacetamide（ DMAc） solution and ultrasonic were utilized to activate fibers. Scanning el...Hemp fibers were treated with different pretreatments before being put into ionic liquid dissolved systems. NaOH,HCI,N,N-dimethylacetamide（ DMAc） solution and ultrasonic were utilized to activate fibers. Scanning electron microscopy（ SEM）,Fourier transform infrared spectroscopy（ FTIR） and X-ray diffraction（ XRD） were used to analyze the morphological and molecular structures of the fiber before and after activation for the comparative analysis. The pretreated fibers were dissolved and the dissolving process of fibers were observed until they were dissolved completely. Experimental studies found that NaOH solution made fibers crystal form change from cellulose Ⅰ to cellulose Ⅱ,and others didn＇t have this kind of change. By comparison,fibers treated by DMAc solution worked best, various methods which affected solubility could be sorted roughly as follows： DMAc ＆gt; ultrasonic ＆gt;HCI ＆gt; NaOH ＆gt; untreated.展开更多
Lignocellulose conversion into cellulosic ethanol and coproducts starts with a pretreatment step.Most current industrial plants of cellulosic ethanol use thermochemical pretreatments under hydrothermal conditions,with...Lignocellulose conversion into cellulosic ethanol and coproducts starts with a pretreatment step.Most current industrial plants of cellulosic ethanol use thermochemical pretreatments under hydrothermal conditions,with or without addition of acid catalyst.Such pretreatments modify biomass chemistry and morphology,particularly at the nanoscale.In this work,we use X-ray diffraction,dynamic vapor sorption and calorimetric thermoporometry to investigate the biomass nanostructural changes promoted by hydrothermal conditions.We compare and differentiate the rind and pith fractions of sugarcane stalks in order to contribute to the understanding of rind-pith contrasting recalcitrance.Moreover,for both cane fractions our results point consistently to cellulose co-crystallization,lignin aggregation,and opening of nanoscale pores as the main nanostructural phenomena occurring during hydrothermal treatments.展开更多
For the bonding couple of S31042 steel and Ni3Al-based superalloy,joint microstructure regulation plays a pivotal role in improving joint performance.Different pretreatment approaches including solution and cold rolli...For the bonding couple of S31042 steel and Ni3Al-based superalloy,joint microstructure regulation plays a pivotal role in improving joint performance.Different pretreatment approaches including solution and cold rolling treatments were severally applied to the two substrates before vacuum diffusion bonding.Cold rolling treatment in S31042 steel substrate before bonding promoted the coarsening and precipitation behaviors of large amounts of Z(NbCrN)phases during the bonding process so that the AlN phase decreased in the joint area because of the consumption of N atom in the Z phase.And solution treatment for Ni3Al-based superalloy increased the grain boundary mobility and led to the occurrence of dynamic recrystallization in the diffusion area of the joint by reducing segregation and homogenizing the microstructure within the substrate.As a result,the bonded sample with two substrates that are pretreated exhibited a better tensile strength and elongation at 700℃.展开更多
We previously developed an HPLC method for determination of lanatoside C, digoxin and α-acetyldigoxin in digitalis glycosides isolated from Digitalis lanata leaves. Here, we present an improved HPLC-UV method to dete...We previously developed an HPLC method for determination of lanatoside C, digoxin and α-acetyldigoxin in digitalis glycosides isolated from Digitalis lanata leaves. Here, we present an improved HPLC-UV method to determine those compounds and deslanoside. We used the improved method to examine the effects of various pretreatments on the amounts of the four compounds isolated from the leaves, with the aim of maximizing the yield of digoxin. Leaves were extracted with 50% methanol, followed by clean-up on a Sep-Pak C18 cartridge prior to HPLC analysis. The amounts of lanatoside C, digoxin and α-acetyldigoxin per 100 mg of the leaves without pretreatment were 115.6, 7.45 and 23.8 μg, respectively (deslanoside was not detected). Pretreatment with acetic acid, which activated deglucosylation mediated by digilanidase present in the leaves, increased the amounts of digoxin and α-acetyldigoxin, while lanatoside C and deslanoside were not detected. Pretreatment with sodium methoxide, which hydrolyzed lanatoside C to deslanoside, increased the yields of deslanoside and digoxin, while lanatoside C and α-acetyldigoxin were not detected. The combination of both pretreatments afforded only digoxin in a yield of 115.1 μg/100 mg leaves. Use of the combined pretreatments appears to be effective for maximizing the yield of digoxin from the leaves.展开更多
This study introduces an innovative immersion pretreatment method at a constant temperature of 65℃to address issues typically encountered during the drying of tomato slices.Fresh tomato slices undergo pretreatment in...This study introduces an innovative immersion pretreatment method at a constant temperature of 65℃to address issues typically encountered during the drying of tomato slices.Fresh tomato slices undergo pretreatment in five different immersion solutions(0.2%KMS,0.2%KMS+1%CaCl_(2),65°Brix Sucrose,1%CaCl_(2),and 1%CaCl_(2)+55%Sucrose)for 25 min,followed by drying at 65℃with a consistent 30%relative humidity using a hot air convection dryer.The investigation evaluates the impact of pretreatment on physicochemical attributes,antioxidant properties,and microbial presence.The most effective pretreatment,involving a 0.2%Potassium Metabisulphite+1%Calcium Chloride solution,improves structural integrity and preserves color,vitamins,and antioxidant activity in dried tomato samples.This pretreatment also resulted in the highest total phenolic content(547.25 mg GAE/100g dry weight),total flavonoid content(39.61 mg QE/100g dry weight),and DPPH radical scavenging activity(65.31 EC_(50) g/100g dry weight).The study concludes that utilizing 0.2%Potassium Metabisulphite+1%Calcium Chloride at 65℃is a viable method for producing high-quality dried tomatoes,preserving desired physicochemical and nutritional attributes.This research addresses the increasing demand for nutritious dehydrated tomato products.展开更多
Many studies have investigated the effects of different pretreatments on the performance of anaerobic digestion of sludge.However,the detailed changes of dissolved organic nitrogen,particularly the release behavior of...Many studies have investigated the effects of different pretreatments on the performance of anaerobic digestion of sludge.However,the detailed changes of dissolved organic nitrogen,particularly the release behavior of proteins and the byproducts of protein hydrolysis-amino acids,are rarely known during anaerobic digestion of sludge by different pretreatments.Here we quantified the changes of three types of proteins and 17 types of amino acids in sludge samples solubilized by ultrasonic,thermal,and acid/alkaline pretreatments and their transformation during anaerobic digestion of sludge.Tryptophan protein,aromatic protein I,aromatic protein II,and cysteine were identified as the key dissolved organic nitrogen responsible for methane production during anaerobic digestion of sludge,regardless of the different pretreatment methods.Different from the depletion of other amino acids,cysteine was resistant to degradation after an incubation period of 30 days in all sludge samples.Meanwhile,the“cysteine and methionine metabolism(K00270)”was absent in all sludge samples by identifying 6755 Kyoto Encyclopedia of Genes and Genomes assignments of genes hits.Cysteine contributed to the generation of methane and the degradation of acetic,propionic,and n-butyric acids through decreasing oxidation-reduction potential and enhancing biomass activity.This study provided an alternative strategy to enhance anaerobic digestion of sludge through in situ production of cysteine.展开更多
This study compared the three wastewater pretreatments of ozonation,Fe2þ-S2O82and freeze-thawing(F/T)in the disintegration,anaerobic digestion(AD)and final disposal of the sludge.The F/T pretreatment increased th...This study compared the three wastewater pretreatments of ozonation,Fe2þ-S2O82and freeze-thawing(F/T)in the disintegration,anaerobic digestion(AD)and final disposal of the sludge.The F/T pretreatment increased the dewaterability and settleability of the sludge by 7.8%and 47.1%,respectively.The ozonation pretreatment formed more volatile fatty acids(VFAs),with a peak value of 320.82 mg SCOD/L and controlled the release of sulfides.The Fe2þ-S2O82pretreatment removed heavy metals through the absorption and flocculation of ferric particles formed in-situ.During the anaerobic digestion of the sludge,the ozonation pretreatment accelerated the hydrolysis rate(k)rather than the biochemical methane potential(B0)of the sludge due to the high VFA content in the supernatant.Comparatively,the F/T pretreatment facilitated the B0 with great economic efficiency by enhancing the solubilisation of the sludge.Although Fe2þ-S2O82pretreatment decreased the methane production,the ferric particle was a unique advantage in the disintegration and harmless disposal of the sludge.The digested sludge had more VFAs after ozonation pretreatment,which contributed to the recycling of carbon.In addition,the lower sludge volume could save the expense of transportation and disposal by ozonation pretreatment.Different pretreatments had different characteristics.The comparative study provided information allowing the selection of the type of pretreatment to achieve different objectives of the treatment and disposal of sludge.展开更多
In recent years,the problem of veterinary drug residues in animal-derived foods has attracted worldwide attention.Developing rapid,simple,highly sensitive,and high-throughput veterinary drug residue detection technolo...In recent years,the problem of veterinary drug residues in animal-derived foods has attracted worldwide attention.Developing rapid,simple,highly sensitive,and high-throughput veterinary drug residue detection technologies has become an urgent need.This paper provides a comprehensive review of the pretreatment and analytical techniques for veterinary drug residue analysis,comparing the detection principles,operational procedures,and respective advantages and disadvantages of various detection technologies.It further explores the future development directions of veterinary drug residue detection technologies.展开更多
The addition of high-content crumb rubber(HCCR)in asphalt can effectively address waste tire pollution and provide sustainable environmental and economic advantages.However,the practical application of conventional ru...The addition of high-content crumb rubber(HCCR)in asphalt can effectively address waste tire pollution and provide sustainable environmental and economic advantages.However,the practical application of conventional rubberized binders is significantly limited by high viscosity and poor storage stability.To address these issues,researchers have pretreated crumb rubber(CR)with oil,but high-temperature performance remains insufficient.Therefore,this study aimed to optimize the viscosity,storage stability,and rheological properties of high-content crumb rubber-modified asphalt(HCCRMA)by varying the pretreatment levels of CR and incorporating various additives,including styrene-butadiene-styrene(SBS),deoiled asphalt(DA),or recycled low-density polyethylene(RLDPE).In addition,CR was pretreated with waste cooking oil(WCO)at various ratios,pre-swelling temperatures,and times.The results show that DA exhibits excellent storage stability and lower viscosity compared with other modifiers in HCCRMA,and the 4%RLDPE with pretreated HCCR has the greatest high-temperature rutting resistance.The inclusion of RLDPE increases the stiffness and elasticity of the modified asphalt,which results in greater high-temperature performance.Additionally,the fluorescence microscopy(FM)test confirms that SBS exhibits better dispersion than other modifiers and forms a more homogeneous phase separation in the HCCRMA.All in all,this research achieved an optimal balance of storage stability and rheological properties in asphalt modified with pretreated HCCR and 6%SBS,which provides a valuable reference for performance improvement of HCCR-modified binders.展开更多
In this study,we selected yeast fermentation,hydrothermal treatment,enzymolysis,ultrasonic treatment,and steam explosion to treat buckwheat bran,based on their known potential to enhance the extraction rate of polyphe...In this study,we selected yeast fermentation,hydrothermal treatment,enzymolysis,ultrasonic treatment,and steam explosion to treat buckwheat bran,based on their known potential to enhance the extraction rate of polyphenol content.Enzymolysis was identified as the most efficient method,leading to a 1.9-fold rise in the extraction rate of polyphenol content from buckwheat and a 1.05-fold increase in ABTS values.To further improve the properties of buckwheat polyphenols,they were complexed with chitooligosaccharide(PP-COS)via hydrogen bonding between the polyphenols’aromatic protons and the hydroxyl group of COS.The antioxidant and antibacterial properties were further augmented in PP-COS,demonstrating excellent storage stability.The ABTS,DPPH,and FRAP values were 1.08-fold,1.12-fold,and 1.04-fold higher than those of control polyphenols,respectively.Additionally,PP-COS was successfully applied to oat flour,further expanding its potential benefits.When compared to pure oat flour,oat flour supplemented with PP-COS exhibited lower pasting parameters,higher solubility and swelling power,lower peak temperature,lower crystallinity,and reduced in vitro digestibility.This study illustrates that various pretreatments exhibit differences in the way and degree of cell wall disruption.The careful selection of optimal pretreatments along with molecular complexation can significantly amplify the extraction efficiency and bioactive potential of grain polyphenols,as exemplified by those present in buckwheat.展开更多
Sewage sludge in the wastewater treatment plants contains considerable amount of antibiotic resistance genes (ARGs). A few studies have reported that anaerobic digestion (AD) could successfully remove some ARGs from s...Sewage sludge in the wastewater treatment plants contains considerable amount of antibiotic resistance genes (ARGs). A few studies have reported that anaerobic digestion (AD) could successfully remove some ARGs from sewage sludge, but information on the fate of ARGs in sludge pretreatment-AD process is still very limited. In this study, three sludge pretreatment methods, including alkaline, thermal hydrolysis and ultrasonic pretreatments, were compared to investigate the distribution and removal of ARGs in the sludge pretreatment-AD process. Results showed that the ARGs removal efficiency of AD itself was approximately 50.77%, and if these three sludge pretreatments were applied, the total ARGs removal efficiency of the whole pretreatment-AD process could be improved up to 52.50%-75.07%. The ultrasonic pretreatment was more efficient than alkaline and thermal hydrolysis pretreatments. Although thermal hydrolysis reduced ARGs obviously, the total ARGs rebounded considerably after inoculation and were only removed slightly in the subsequent AD process. Furthermore, it was found that the total ARGs concentration significantly correlated with the amount of 16S rRNA gene during the pretreatment and AD processes, and the bacteria carrying ARGs could be mainly affiliated with Proteobacteria.展开更多
In order to explore the effects of different pretreatments on the pore structure of Chinese yam during Microwave Freeze Drying(MFD),the samples were treated by typical drying pretreatments including osmosis,blanching ...In order to explore the effects of different pretreatments on the pore structure of Chinese yam during Microwave Freeze Drying(MFD),the samples were treated by typical drying pretreatments including osmosis,blanching and ultrasound,and compared with the untreated samples.The results showed that the pretreatment had significant impacts on the porosity of MFD Chinese yam.Ultrasonic pretreatment could obtain the highest open porosity,and the internal pore network structure of the material showed a uniform sponge shape.The shape of pores obtained by blanching pretreatment was the most irregular.The pore network structure obtained by different pretreatments could result in various product texture and rehydration,which implied that pretreatment methods should be carefully selected according to actual requirements.All these pretreatments could improve the open porosity of MFD Chinese yam,which result in a better rehydration capability.Among them,ultrasonic treatment is worth further investigating.展开更多
Pelletization,a form of densification,increases bulk density and improves the convenience and accessibility of biomass feedstock due to the uniform shape and size.Pretreatment of biomass enhances the breakdown and acc...Pelletization,a form of densification,increases bulk density and improves the convenience and accessibility of biomass feedstock due to the uniform shape and size.Pretreatment of biomass enhances the breakdown and accessibility of the cross-linking lignin,which acts as a binding agent.In this study,pelletization of radio frequency-alkaline and steam explosion pretreated barley straw was performed.Three levels of temperature(70oC,80oC,and 90oC),five levels of the mass ratio of biomass to NaOH solution(1:4,1:5,1:6,1:7,and 1:8),one hour equilibration time,biomass screen size of 1.6 mm,1%NaOH concentration,and 20 min residence time in the radio frequency chamber were used for the radio frequency-alkaline pretreatment.Three levels of steam temperature(140oC,160oC,and 180oC),three levels of moisture content of 8%,30%,and 50%(mass fraction of total mass),and 5 min and 10 min exposure to steam were tested for the steam explosion pretreatment.The effects of both pretreatment methods were evaluated by pelletizing the pretreated and non-pretreated barley straw samples in a single pelleting unit.The pellet density,tensile strength,durability,dimensional stability,and color of the pellets were determined.Radio frequency-alkaline pretreatment with the use of 1%NaOH solution and a ratio of biomass:NaOH solution of 1:8 has significant effect(P<0.05)on the breakdown of the lignified matrix,resulting in pellets with superior physical characteristics.The steam exploded samples pretreated at higher temperatures(180ºC)and retention time of 10 min resulted into pellets with good physical qualities.展开更多
In this study,we aimed to verify the effectiveness of fermentation as a pretreatment in Nile tilapia(Oreochromis niloticus)skin gelatin production and to assess its effects on the extracted gelatin.Chemical-gelatin(CG...In this study,we aimed to verify the effectiveness of fermentation as a pretreatment in Nile tilapia(Oreochromis niloticus)skin gelatin production and to assess its effects on the extracted gelatin.Chemical-gelatin(CG)and fermentation-gelatin(FG)were extracted using hot water from tilapia skin after immersion in chemical reagents(sodium hydroxide and butanol)and after fermentation with Bacillus velezensis FEL-BM21,respectively.FG presented a higher recovery(27.40%),yield(49.99%),and imino acid(proline and hydroxyproline)content(177.17±0.35 residues/1000 residues)than CG,but had a lower molecular weight.Fourier transform infrared and circular dichroism spectroscopy confirmed that the collagen was denatured,and scanning electron microscopy revealed that FG had a more continuous filamentous structure than CG.Furthermore,except for transmittance(66.19%at 450 nm and 86.36%at 620 nm),FG exhibited higher gel strength(492.81 g),gelling point(28.93℃),and melting point(18.33℃)than CG.These findings suggest that fermentation can be used to treat gelatin raw materials without negatively affecting the structure of gelatin.Moreover,fermentation has potential industrial applications as an alternative to chemical treatment.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
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
基金the Brazilian research funding agencies CNPq and FUNDECT for their financial support.
文摘Cellulosic ethanol involves the following production steps: physical and/or chemical pretreatment, biological treatment, fermentation and distillation. First three steps are also the bottlenecks for the production of cellulosic ethanol and its co-products. Their production still pose some difficulties in terms of pretreatment, the high cost of enzymes for substrate hydrolysis, the formation of inhibitory compounds in the hydrolyzate, the lack of efficient and viable microorganisms for industrial fermentation of hexose and pentose among others. The solution or minimization of these difficulties may lead to numerous socio-environmental, political, and economic advantages for cellulosic ethanol production. This paper highlights the potential of different substrates, pretreatments, microorganisms and bioprocesses for cellulosic ethanol production.
基金National Natural Science Foundation of China,No.82172196,No.82372507,and No.81971891.
文摘In this editorial,we offer our perspective on the groundbreaking study entitled“Hypoxia and inflammatory factor preconditioning enhances the immunosup-pressive properties of human umbilical cord mesenchymal stem cells”,recently published in World Journal of Stem Cells.Despite over three decades of research on the clinical application of mesenchymal stem cells(MSCs),only a few therapeutic products have made it to clinical use,due to multiple preclinical and clinical challenges yet to be addressed.The study proved the hypoxia and inflammatory factor preconditioning led to higher immunosuppressive effects of MSCs without damaging their biological characteristics,which revealed the combination of inflammatory factors and hypoxic preconditioning offers a promising approach to enhance the function of MSCs.As we delve deeper into the intricacies of pretreat-ment methodologies,we anticipate a transformative shift in the landscape of MSC-based therapies,ultimately contributing to improved patient outcomes and advancing the field as a whole.
基金supported by the Major Science and Technology Program for Water Pollution Control and Treatment(No.2018ZX07110-002)。
文摘This study investigated a combined low-thermal and CaO_(2)pretreatment to enhance the volatile fatty acid(VFA)production from waste activated sludge(WAS).The fermentative product was added to a sequencing batch reactor(SBR)as an external carbon source to enhance nitrogen removal.The results showed that the combined pretreatment improved WAS solubilization,releasing more biodegradable substrates,such as proteins and polysaccharides,from TB-EPS to LB-EPS and S-EPS.The maximum VFA production of 3529±188 mg COD/L was obtained in the combined pretreatment(0.2 g CaO_(2)/g VS+70℃for 60 min),which was 2.1 and 1.4-fold of that obtained from the sole low-thermal pretreatment and the control test,respectively.Consequently,when the fermentative liquid was added as an external denitrification carbon source,the effluent total nitrogen decreased to Class A of the discharge standard for pollutants in rural wastewater treatment plants in most areas of China.
基金Supported by Guide Project of Xinjiang Academy of Agricultural and Reclamation Science(71YYD201408)Xinjiang Science and Technology Support Project of Xinjiang Production and Construction Corps(2013AB020)
文摘This paper studies the influence of three different pretreatments( blanching,citric acid soaking,and Na Cl soaking) on the moisture content,degree of puffing,color,hardness and crispness of Hami melon under explosion puffing drying at modified temperature and pressure in Xinjiang. The results show that using 60 s blanching pretreatment can help to reduce the moisture content of puffed product while maintaining product color; 2. 5% citric acid pretreatment can make products maintain high degree of puffing and crispness,but reduce product color; 2%Na Cl penetrating fluid plays a significant role in maintaining product color,while maintaining crispness.
文摘Hemp fibers were treated with different pretreatments before being put into ionic liquid dissolved systems. NaOH,HCI,N,N-dimethylacetamide（ DMAc） solution and ultrasonic were utilized to activate fibers. Scanning electron microscopy（ SEM）,Fourier transform infrared spectroscopy（ FTIR） and X-ray diffraction（ XRD） were used to analyze the morphological and molecular structures of the fiber before and after activation for the comparative analysis. The pretreated fibers were dissolved and the dissolving process of fibers were observed until they were dissolved completely. Experimental studies found that NaOH solution made fibers crystal form change from cellulose Ⅰ to cellulose Ⅱ,and others didn＇t have this kind of change. By comparison,fibers treated by DMAc solution worked best, various methods which affected solubility could be sorted roughly as follows： DMAc ＆gt; ultrasonic ＆gt;HCI ＆gt; NaOH ＆gt; untreated.
文摘Lignocellulose conversion into cellulosic ethanol and coproducts starts with a pretreatment step.Most current industrial plants of cellulosic ethanol use thermochemical pretreatments under hydrothermal conditions,with or without addition of acid catalyst.Such pretreatments modify biomass chemistry and morphology,particularly at the nanoscale.In this work,we use X-ray diffraction,dynamic vapor sorption and calorimetric thermoporometry to investigate the biomass nanostructural changes promoted by hydrothermal conditions.We compare and differentiate the rind and pith fractions of sugarcane stalks in order to contribute to the understanding of rind-pith contrasting recalcitrance.Moreover,for both cane fractions our results point consistently to cellulose co-crystallization,lignin aggregation,and opening of nanoscale pores as the main nanostructural phenomena occurring during hydrothermal treatments.
基金supported by the National Natural Science Foundation of China(Grant Nos.52034004 and 52075373).
文摘For the bonding couple of S31042 steel and Ni3Al-based superalloy,joint microstructure regulation plays a pivotal role in improving joint performance.Different pretreatment approaches including solution and cold rolling treatments were severally applied to the two substrates before vacuum diffusion bonding.Cold rolling treatment in S31042 steel substrate before bonding promoted the coarsening and precipitation behaviors of large amounts of Z(NbCrN)phases during the bonding process so that the AlN phase decreased in the joint area because of the consumption of N atom in the Z phase.And solution treatment for Ni3Al-based superalloy increased the grain boundary mobility and led to the occurrence of dynamic recrystallization in the diffusion area of the joint by reducing segregation and homogenizing the microstructure within the substrate.As a result,the bonded sample with two substrates that are pretreated exhibited a better tensile strength and elongation at 700℃.
文摘We previously developed an HPLC method for determination of lanatoside C, digoxin and α-acetyldigoxin in digitalis glycosides isolated from Digitalis lanata leaves. Here, we present an improved HPLC-UV method to determine those compounds and deslanoside. We used the improved method to examine the effects of various pretreatments on the amounts of the four compounds isolated from the leaves, with the aim of maximizing the yield of digoxin. Leaves were extracted with 50% methanol, followed by clean-up on a Sep-Pak C18 cartridge prior to HPLC analysis. The amounts of lanatoside C, digoxin and α-acetyldigoxin per 100 mg of the leaves without pretreatment were 115.6, 7.45 and 23.8 μg, respectively (deslanoside was not detected). Pretreatment with acetic acid, which activated deglucosylation mediated by digilanidase present in the leaves, increased the amounts of digoxin and α-acetyldigoxin, while lanatoside C and deslanoside were not detected. Pretreatment with sodium methoxide, which hydrolyzed lanatoside C to deslanoside, increased the yields of deslanoside and digoxin, while lanatoside C and α-acetyldigoxin were not detected. The combination of both pretreatments afforded only digoxin in a yield of 115.1 μg/100 mg leaves. Use of the combined pretreatments appears to be effective for maximizing the yield of digoxin from the leaves.
文摘This study introduces an innovative immersion pretreatment method at a constant temperature of 65℃to address issues typically encountered during the drying of tomato slices.Fresh tomato slices undergo pretreatment in five different immersion solutions(0.2%KMS,0.2%KMS+1%CaCl_(2),65°Brix Sucrose,1%CaCl_(2),and 1%CaCl_(2)+55%Sucrose)for 25 min,followed by drying at 65℃with a consistent 30%relative humidity using a hot air convection dryer.The investigation evaluates the impact of pretreatment on physicochemical attributes,antioxidant properties,and microbial presence.The most effective pretreatment,involving a 0.2%Potassium Metabisulphite+1%Calcium Chloride solution,improves structural integrity and preserves color,vitamins,and antioxidant activity in dried tomato samples.This pretreatment also resulted in the highest total phenolic content(547.25 mg GAE/100g dry weight),total flavonoid content(39.61 mg QE/100g dry weight),and DPPH radical scavenging activity(65.31 EC_(50) g/100g dry weight).The study concludes that utilizing 0.2%Potassium Metabisulphite+1%Calcium Chloride at 65℃is a viable method for producing high-quality dried tomatoes,preserving desired physicochemical and nutritional attributes.This research addresses the increasing demand for nutritious dehydrated tomato products.
基金supported by the National Natural Science Foundation of China(Grant Nos.51708239 and U1901216)Natural Science Foundation of Hubei Province(No.2020CFA042)+1 种基金Applied Basic Research Program of Wuhan(No.2020020601012277)Additionally,we would also like to thank the Analytical and Testing Center of Huazhong University of Science and Technology for providing experimental measurements.
文摘Many studies have investigated the effects of different pretreatments on the performance of anaerobic digestion of sludge.However,the detailed changes of dissolved organic nitrogen,particularly the release behavior of proteins and the byproducts of protein hydrolysis-amino acids,are rarely known during anaerobic digestion of sludge by different pretreatments.Here we quantified the changes of three types of proteins and 17 types of amino acids in sludge samples solubilized by ultrasonic,thermal,and acid/alkaline pretreatments and their transformation during anaerobic digestion of sludge.Tryptophan protein,aromatic protein I,aromatic protein II,and cysteine were identified as the key dissolved organic nitrogen responsible for methane production during anaerobic digestion of sludge,regardless of the different pretreatment methods.Different from the depletion of other amino acids,cysteine was resistant to degradation after an incubation period of 30 days in all sludge samples.Meanwhile,the“cysteine and methionine metabolism(K00270)”was absent in all sludge samples by identifying 6755 Kyoto Encyclopedia of Genes and Genomes assignments of genes hits.Cysteine contributed to the generation of methane and the degradation of acetic,propionic,and n-butyric acids through decreasing oxidation-reduction potential and enhancing biomass activity.This study provided an alternative strategy to enhance anaerobic digestion of sludge through in situ production of cysteine.
基金This study was supported by the State Key Laboratory of Urban Water Resource and Environment(Harbin Institute of Technology)(No.2019TS04).
文摘This study compared the three wastewater pretreatments of ozonation,Fe2þ-S2O82and freeze-thawing(F/T)in the disintegration,anaerobic digestion(AD)and final disposal of the sludge.The F/T pretreatment increased the dewaterability and settleability of the sludge by 7.8%and 47.1%,respectively.The ozonation pretreatment formed more volatile fatty acids(VFAs),with a peak value of 320.82 mg SCOD/L and controlled the release of sulfides.The Fe2þ-S2O82pretreatment removed heavy metals through the absorption and flocculation of ferric particles formed in-situ.During the anaerobic digestion of the sludge,the ozonation pretreatment accelerated the hydrolysis rate(k)rather than the biochemical methane potential(B0)of the sludge due to the high VFA content in the supernatant.Comparatively,the F/T pretreatment facilitated the B0 with great economic efficiency by enhancing the solubilisation of the sludge.Although Fe2þ-S2O82pretreatment decreased the methane production,the ferric particle was a unique advantage in the disintegration and harmless disposal of the sludge.The digested sludge had more VFAs after ozonation pretreatment,which contributed to the recycling of carbon.In addition,the lower sludge volume could save the expense of transportation and disposal by ozonation pretreatment.Different pretreatments had different characteristics.The comparative study provided information allowing the selection of the type of pretreatment to achieve different objectives of the treatment and disposal of sludge.
基金Supported by Tangshan Science and Technology Planning Project(25150202E).
文摘In recent years,the problem of veterinary drug residues in animal-derived foods has attracted worldwide attention.Developing rapid,simple,highly sensitive,and high-throughput veterinary drug residue detection technologies has become an urgent need.This paper provides a comprehensive review of the pretreatment and analytical techniques for veterinary drug residue analysis,comparing the detection principles,operational procedures,and respective advantages and disadvantages of various detection technologies.It further explores the future development directions of veterinary drug residue detection technologies.
基金supported by the Transportation Science and Technology Program of Henan Province(grant number:2023-4-2)the Key Research and Development Program of Ningxia Science and Technology Department(grant number:2022BEG02008)+2 种基金China Communications Construction Group Co.,Ltd.Science and Technology R&D Project(grant number:2021KJW02)the Research and Development Program of Henan Transportation Investment Group Co.,Ltd.(grant number:HNJT2025-1-9)the Postdoctoral Fellowship Program of CPSF(grand number:GZC20251139).
文摘The addition of high-content crumb rubber(HCCR)in asphalt can effectively address waste tire pollution and provide sustainable environmental and economic advantages.However,the practical application of conventional rubberized binders is significantly limited by high viscosity and poor storage stability.To address these issues,researchers have pretreated crumb rubber(CR)with oil,but high-temperature performance remains insufficient.Therefore,this study aimed to optimize the viscosity,storage stability,and rheological properties of high-content crumb rubber-modified asphalt(HCCRMA)by varying the pretreatment levels of CR and incorporating various additives,including styrene-butadiene-styrene(SBS),deoiled asphalt(DA),or recycled low-density polyethylene(RLDPE).In addition,CR was pretreated with waste cooking oil(WCO)at various ratios,pre-swelling temperatures,and times.The results show that DA exhibits excellent storage stability and lower viscosity compared with other modifiers in HCCRMA,and the 4%RLDPE with pretreated HCCR has the greatest high-temperature rutting resistance.The inclusion of RLDPE increases the stiffness and elasticity of the modified asphalt,which results in greater high-temperature performance.Additionally,the fluorescence microscopy(FM)test confirms that SBS exhibits better dispersion than other modifiers and forms a more homogeneous phase separation in the HCCRMA.All in all,this research achieved an optimal balance of storage stability and rheological properties in asphalt modified with pretreated HCCR and 6%SBS,which provides a valuable reference for performance improvement of HCCR-modified binders.
基金supported by the National Natural Science Foundation of China(grant No.31601477)the project of Science and Technology Department of Shanxi Province(202102140601014).
文摘In this study,we selected yeast fermentation,hydrothermal treatment,enzymolysis,ultrasonic treatment,and steam explosion to treat buckwheat bran,based on their known potential to enhance the extraction rate of polyphenol content.Enzymolysis was identified as the most efficient method,leading to a 1.9-fold rise in the extraction rate of polyphenol content from buckwheat and a 1.05-fold increase in ABTS values.To further improve the properties of buckwheat polyphenols,they were complexed with chitooligosaccharide(PP-COS)via hydrogen bonding between the polyphenols’aromatic protons and the hydroxyl group of COS.The antioxidant and antibacterial properties were further augmented in PP-COS,demonstrating excellent storage stability.The ABTS,DPPH,and FRAP values were 1.08-fold,1.12-fold,and 1.04-fold higher than those of control polyphenols,respectively.Additionally,PP-COS was successfully applied to oat flour,further expanding its potential benefits.When compared to pure oat flour,oat flour supplemented with PP-COS exhibited lower pasting parameters,higher solubility and swelling power,lower peak temperature,lower crystallinity,and reduced in vitro digestibility.This study illustrates that various pretreatments exhibit differences in the way and degree of cell wall disruption.The careful selection of optimal pretreatments along with molecular complexation can significantly amplify the extraction efficiency and bioactive potential of grain polyphenols,as exemplified by those present in buckwheat.
基金the National Natural Science Foundation of China (Grant No. 21407113)the Tianjin City Science and Technology Support Program Project (No. 16YFZCSF00320)the Key Projects of National Water Pollution Control and Management of China (No. 2015ZX07306001).
文摘Sewage sludge in the wastewater treatment plants contains considerable amount of antibiotic resistance genes (ARGs). A few studies have reported that anaerobic digestion (AD) could successfully remove some ARGs from sewage sludge, but information on the fate of ARGs in sludge pretreatment-AD process is still very limited. In this study, three sludge pretreatment methods, including alkaline, thermal hydrolysis and ultrasonic pretreatments, were compared to investigate the distribution and removal of ARGs in the sludge pretreatment-AD process. Results showed that the ARGs removal efficiency of AD itself was approximately 50.77%, and if these three sludge pretreatments were applied, the total ARGs removal efficiency of the whole pretreatment-AD process could be improved up to 52.50%-75.07%. The ultrasonic pretreatment was more efficient than alkaline and thermal hydrolysis pretreatments. Although thermal hydrolysis reduced ARGs obviously, the total ARGs rebounded considerably after inoculation and were only removed slightly in the subsequent AD process. Furthermore, it was found that the total ARGs concentration significantly correlated with the amount of 16S rRNA gene during the pretreatment and AD processes, and the bacteria carrying ARGs could be mainly affiliated with Proteobacteria.
基金The authors acknowledge that this work was financially supported by the National Natural Science Foundation of China(Contract No.31671907 and No.31972207).
文摘In order to explore the effects of different pretreatments on the pore structure of Chinese yam during Microwave Freeze Drying(MFD),the samples were treated by typical drying pretreatments including osmosis,blanching and ultrasound,and compared with the untreated samples.The results showed that the pretreatment had significant impacts on the porosity of MFD Chinese yam.Ultrasonic pretreatment could obtain the highest open porosity,and the internal pore network structure of the material showed a uniform sponge shape.The shape of pores obtained by blanching pretreatment was the most irregular.The pore network structure obtained by different pretreatments could result in various product texture and rehydration,which implied that pretreatment methods should be carefully selected according to actual requirements.All these pretreatments could improve the open porosity of MFD Chinese yam,which result in a better rehydration capability.Among them,ultrasonic treatment is worth further investigating.
文摘Pelletization,a form of densification,increases bulk density and improves the convenience and accessibility of biomass feedstock due to the uniform shape and size.Pretreatment of biomass enhances the breakdown and accessibility of the cross-linking lignin,which acts as a binding agent.In this study,pelletization of radio frequency-alkaline and steam explosion pretreated barley straw was performed.Three levels of temperature(70oC,80oC,and 90oC),five levels of the mass ratio of biomass to NaOH solution(1:4,1:5,1:6,1:7,and 1:8),one hour equilibration time,biomass screen size of 1.6 mm,1%NaOH concentration,and 20 min residence time in the radio frequency chamber were used for the radio frequency-alkaline pretreatment.Three levels of steam temperature(140oC,160oC,and 180oC),three levels of moisture content of 8%,30%,and 50%(mass fraction of total mass),and 5 min and 10 min exposure to steam were tested for the steam explosion pretreatment.The effects of both pretreatment methods were evaluated by pelletizing the pretreated and non-pretreated barley straw samples in a single pelleting unit.The pellet density,tensile strength,durability,dimensional stability,and color of the pellets were determined.Radio frequency-alkaline pretreatment with the use of 1%NaOH solution and a ratio of biomass:NaOH solution of 1:8 has significant effect(P<0.05)on the breakdown of the lignified matrix,resulting in pellets with superior physical characteristics.The steam exploded samples pretreated at higher temperatures(180ºC)and retention time of 10 min resulted into pellets with good physical qualities.
基金supported by the Southern Marine Science and Engineering Laboratory(Zhanjiang)[ZJW-2019-07]the Innovation and Development Project about Marine Economy Demonstration of Zhanjiang City[2017C8B1]+1 种基金the Innovation Team Construction Project of Modern Agricultural Industry Technology System in Guangdong Province[2021KJ150]Science and Technology plan project of Zhanjiang City[2019A03021].
文摘In this study,we aimed to verify the effectiveness of fermentation as a pretreatment in Nile tilapia(Oreochromis niloticus)skin gelatin production and to assess its effects on the extracted gelatin.Chemical-gelatin(CG)and fermentation-gelatin(FG)were extracted using hot water from tilapia skin after immersion in chemical reagents(sodium hydroxide and butanol)and after fermentation with Bacillus velezensis FEL-BM21,respectively.FG presented a higher recovery(27.40%),yield(49.99%),and imino acid(proline and hydroxyproline)content(177.17±0.35 residues/1000 residues)than CG,but had a lower molecular weight.Fourier transform infrared and circular dichroism spectroscopy confirmed that the collagen was denatured,and scanning electron microscopy revealed that FG had a more continuous filamentous structure than CG.Furthermore,except for transmittance(66.19%at 450 nm and 86.36%at 620 nm),FG exhibited higher gel strength(492.81 g),gelling point(28.93℃),and melting point(18.33℃)than CG.These findings suggest that fermentation can be used to treat gelatin raw materials without negatively affecting the structure of gelatin.Moreover,fermentation has potential industrial applications as an alternative to chemical treatment.
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.
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.
