The concept of Industrial Biosystems Engineering (IBsE) was suggested as a new engineering branch to be developed for meeting the needs for science, technology and professionals by the upcoming bioeconomy. With emphas...The concept of Industrial Biosystems Engineering (IBsE) was suggested as a new engineering branch to be developed for meeting the needs for science, technology and professionals by the upcoming bioeconomy. With emphasis on systems, IBsE builds upon the interfaces between systems biology, bioprocessing, and systems engineering. This paper discussed the background, the suggested definition, the theoretical framework and methodologies of this new discipline as well as its challenges and future development.展开更多
Identifying the factors that contribute to individual susceptibility to cancer is essential for both prevention and treatment.The advancement of biotechnologies,particularly next-generation sequencing,has accelerated ...Identifying the factors that contribute to individual susceptibility to cancer is essential for both prevention and treatment.The advancement of biotechnologies,particularly next-generation sequencing,has accelerated the discovery of genetic variants linked to cancer susceptibility.While hundreds of cancer-susceptibility genes have been identified,they only explain a small fraction of the overall cancer risk,a phenomenon known as"missing heritability".Despite progress,even considering factors such as epistasis,epigenetics,and gene-environment interactions,the missing heritability remains unresolved.Recent research has revealed that an individual's microbiome composition plays a significant role in cancer susceptibility through several mechanisms,such as modulating immune cell activity and influencing the presence or removal of environmental carcinogens.In this review,we examine the multifaceted roles of the microbiome in cancer risk and explore gene-microbiome and environment-microbiome interactions that may contribute to cancer susceptibility.Additionally,we highlight the importance of experimental models,such as collaborative cross mice,and advanced analytical tools,like artificial intelligence,in identifying microbial factors associated with cancer risk.Understanding these microbial determinants can open new avenues for interventions aimed at reducing cancer risk and guide the development of more effective cancer treatments.展开更多
Humins,as a group of by-products formed through the condensation and coupling of fragment intermediates during lignocellulosic biomass refining,can cause numerous negative effects such as the wastage of carbon resourc...Humins,as a group of by-products formed through the condensation and coupling of fragment intermediates during lignocellulosic biomass refining,can cause numerous negative effects such as the wastage of carbon resources,clogging of reactor piping,deactivation of catalyst,and barriers to product separation.Elucidating the generation mechanism of humins,developing efficient inhibitors,and even utilizing them as a resource,both from the perspective of atom economy and safe production,constitutes a research endeavor replete with challenges and opportunities.Orbiting the critical issue of humins structure and its generation mechanism from cellulose and hemicellulose resources,the random condensation between intermediates such as 5-hydroxymethylfurfural,furfural,2,5-dioxo-6-hydroxyhexanal,and 1,2,4-benzenetriol etc.were systematically summarized.Additionally,the presence of lignin in real biorefining processes further promotes the formation of a special type of humins known as"pseudo-lignin".The influences of various factors,including raw materials,reaction temperature and time,acid-base environment,as well as solvent systems and catalysts,on the formation of humins were comprehensively analyzed.To minimize the formation of humins,the design of efficient solvent systems and catalysts is crucial.Furthermore,this review investigates the approaches to value-added applications of humins.The corresponding summary could provide guidance for the development of the humins chemistry.展开更多
BACKGROUND The understanding of bile acid(BA)and unsaturated fatty acid(UFA)profiles,as well as their dysregulation,remains elusive in individuals with type 2 diabetes mellitus(T2DM)coexisting with non-alcoholic fatty...BACKGROUND The understanding of bile acid(BA)and unsaturated fatty acid(UFA)profiles,as well as their dysregulation,remains elusive in individuals with type 2 diabetes mellitus(T2DM)coexisting with non-alcoholic fatty liver disease(NAFLD).Investigating these metabolites could offer valuable insights into the pathophy-siology of NAFLD in T2DM.AIM To identify potential metabolite biomarkers capable of distinguishing between NAFLD and T2DM.METHODS A training model was developed involving 399 participants,comprising 113 healthy controls(HCs),134 individuals with T2DM without NAFLD,and 152 individuals with T2DM and NAFLD.External validation encompassed 172 participants.NAFLD patients were divided based on liver fibrosis scores.The analytical approach employed univariate testing,orthogonal partial least squares-discriminant analysis,logistic regression,receiver operating characteristic curve analysis,and decision curve analysis to pinpoint and assess the diagnostic value of serum biomarkers.RESULTS Compared to HCs,both T2DM and NAFLD groups exhibited diminished levels of specific BAs.In UFAs,particular acids exhibited a positive correlation with NAFLD risk in T2DM,while theω-6:ω-3 UFA ratio demonstrated a negative correlation.Levels ofα-linolenic acid andγ-linolenic acid were linked to significant liver fibrosis in NAFLD.The validation cohort substantiated the predictive efficacy of these biomarkers for assessing NAFLD risk in T2DM patients.CONCLUSION This study underscores the connection between altered BA and UFA profiles and the presence of NAFLD in individuals with T2DM,proposing their potential as biomarkers in the pathogenesis of NAFLD.展开更多
Peanuts pods grow underground and mature unevenly, resulting that choosing the correct time to harvest is more complicated than other crops. Pod maturity can be determined by blasting with a pressure washer to remove ...Peanuts pods grow underground and mature unevenly, resulting that choosing the correct time to harvest is more complicated than other crops. Pod maturity can be determined by blasting with a pressure washer to remove outer skin of the pod (exocarp) to expose the color of the middle layer (mesocarp). The mesocarp color changes with maturity from white to yellow, orange, brown and finally black. The sum of percentage from orange, brown, and black mesocarp (OBB) color and black color (BL) represents the kernels that are mature enough to harvest. The goal of this research is to identify methodologies to estimate OBB and BL of the pods using RGB images taken in the field and validate the proposed model using other pod images. The Mahalanobis distance classification method was used to process sets of images and calculate pod area (number of pixels) corresponding to two classes (mesocarp and background) with nine different color groups. The results showed a performance of 94% effectiveness for mesocarp using Mahalanobis distance classification. Statistical regression for OBB and BL was developed based on 315 images of peanut pods taken from the field. The R2 and root mean square error of predicted and actual OBB were 0.93 and 4.1%, respectively. The R2 and root mean square error of predicted and actual BL were 0.88 and 1.8%, respectively. The validation of OBB using other images provided reasonable estimation (R2 = 0.98 and RMSE = 2.73%). This study introduces a novel, cost-effective, and non-destructive method for estimating peanut maturity using RGB imagery and Mahalanobis distance classification in the field. This innovative approach addresses the limitations of traditional methods and offers a robust alternative for real-time maturity assessment.展开更多
The increasing use of traditional agricultural plastic mulch films(PMs)has raised significant environ-mental concerns,prompting the search for sustainable alternatives.Soil-biodegradable mulch films(BDMs)are often pro...The increasing use of traditional agricultural plastic mulch films(PMs)has raised significant environ-mental concerns,prompting the search for sustainable alternatives.Soil-biodegradable mulch films(BDMs)are often proposed as eco-friendly replacements;however,their widespread adoption remains contentious.This review employs a comparative life cycle assessment perspective to evaluate the environmental impact of PMs and BDMs across their production,use,and end-of-life stages,providing strategies to mitigate their impact on agroecosystems.BDMs generally exhibit lower energy use and greenhouse gas emissions than PMs but contribute to greater land-use demands.Reported eutrophica-tion and acidification potentials are less consistent,varying based on feedstock types and the scope of assessment of BDM,as well as the end-of-life management of PM.The environmental burden of both mulch types is influenced by the life cycle stage,polymer composition,farming practices,additives,film thickness,and local climatic conditions.The manufacturing stage is a major contributor to energy use and greenhouse gas emissions for both PMs and BDMs,despite their shared benefits of increasing crop yields.However,post-use impacts are more pronounced for PMs,driven by end-of-life strategy and adsorbed waste content.While starch-based BDMs offer a more sustainable alternative to PMs,un-certainties regarding the residence time of BDM residues in soil(albeit shorter than PM residues)and their effects on soil health,coupled with higher production costs,impede widespread adoption.For BDM end-of-life,soil biodegradation is recommended.Energy and material recovery options are crucial for PM end-of-life,with mechanical recycling preferred,although it requires addressing eutrophication and human toxicity.This review discusses these complexities within specific contexts and provides action-able insights to guide the sustainable integration of mulch films into agricultural practices.展开更多
The aviation industry faces various challenges in meeting long-term sustainability goals amidst surging demand for air travel and growing environmental concerns of the general public.The year 2050 is set as an ambitio...The aviation industry faces various challenges in meeting long-term sustainability goals amidst surging demand for air travel and growing environmental concerns of the general public.The year 2050 is set as an ambitious goal for net zero emissions,a substantial reduction in carbon dioxide emissions per passenger kilometer flown,major improvements in aircraft energy efficiency,and a development towards autonomous,intelligent operations.This review explores the pivotal role of advancements in engineering for achieving sustainability in aviation.Through a comprehensive review of existing literature and case studies,our work highlights how innovations in all aspects of aircraft engineering coupled with operations-related technologies,offer promising solutions to mitigate environmental impact,enhance efficiency,and ensure long-term sustainability in aviation operations.To discuss the necessary advances,we promote the so-called‘DESIGN and be SMART’framework,consisting of eleven complementary engineering challenges towards reaching sustainability.To address the high safety levels reached in air transportation,our DESIGN and be SMART framework also addresses the safety assurance challenge that is overarching each of the eleven engineering challenges.We believe that through an orchestrated integration of hardware advancements with innovative software solutions,and novel safety assurance methods,the aviation industry can realize synergistic benefits that drive sustainable growth of air transportation.Our review contributes to such an orchestration by describing the status quo and research challenges ahead.展开更多
AIM： To investigate whether a fuzzy logic model could predict colorectal cancer （CRC） risk engendered by smoking in hereditary non-polyposis colorectal cancer （HNPCC） patients. METHODS： Three hundred and forty H...AIM： To investigate whether a fuzzy logic model could predict colorectal cancer （CRC） risk engendered by smoking in hereditary non-polyposis colorectal cancer （HNPCC） patients. METHODS： Three hundred and forty HNPCC mismatch repair （MMR） mutation carriers from the Creighton University Hereditary Cancer Institute Registry were selected for modeling. Age-dependent curves were generated to elucidate the joint effects between gene mutation （hMLH1 or hMSH2）, gender, and smoking status on the probability of developing CRC. RESULTS： Smoking significantly increased CRC risk in male hMSH2 mutation carriers （P 〈 0.05）. hMLH1 mutations augmented CRC risk relative to hMSH2 mutation carriers for males （P 〈 0.05）. Males had a significantly higher risk of CRC than females for hMLH1 non smokers （P 〈 0.05）, hMLH1 smokers （P 〈 0.1） and hMSH2 smokers （P 〈 0.1）. Smoking promoted CRC in a dose-dependent manner in hMSH2 in males （P 〈 0.05）. Females with hMSH2 mutations and both sexes with the hMLH1 groups only demonstrated a smoking effect after an extensive smoking history （P 〈 0.05）. CONCLUSION： CRC promotion by smoking in HNPCC patients is dependent on gene mutation, gender and age. These data demonstrate that fuzzy modeling may enable formulation of clinical risk scores, thereby allowing individualization of CRC prevention strategies.展开更多
Aqueous ammonia was used to pretreat wheat straw to improve biodegradability and provide nitrogen source for enhancing biogas production. Three doses of ammonia(2%, 4%, and 6%, dry matter) and three moisture contents(...Aqueous ammonia was used to pretreat wheat straw to improve biodegradability and provide nitrogen source for enhancing biogas production. Three doses of ammonia(2%, 4%, and 6%, dry matter) and three moisture contents(30%, 60%, and 80%, dry matter) were applied to pretreat wheat straw for 7 days. The pretreated wheat straws were anaerobically digested at three loading rates(50, 65, and 80 g·L-1) to produce biogas. The results indicated that the wheat straw pretreated with 80% moisture content and 4% ammonia achieved the highest methane yield of 199.7 ml·g-1(based on per unit volatile solids loaded), with shorter digestion time(T80) of 25 days at the loading rate of 65 g·L-1compared to untreated one. The main chemical compositions of wheat straw were also analyzed. The cellulose and hemicellulose contents were decomposed by 2%-20% and 26%-42%, respectively,while the lignin content was hardly removed, cold-water and hot-water extracts were increased by 4%-44%, and12%-52%, respectively, for the ammonia-pretreated wheat straws at different moisture contents. The appropriate C/N ratio and decomposition of original chemical compositions into relatively readily biodegradable substances will improve the biodegradability and biogas yield.展开更多
CO2 removal from biogas by water washing system was investigated with various parameters, including liquid/ gas ratio, pressure, temperature, and CO2 content. The results indicate that CO2 removal ratio could reach 34...CO2 removal from biogas by water washing system was investigated with various parameters, including liquid/ gas ratio, pressure, temperature, and CO2 content. The results indicate that CO2 removal ratio could reach 34.6%- 94.2% as liquid/gas ratio increased from 0.14 to 0.50. Increasing pressure （from 0.8 to 1.2 MPa） could improve gas purification with a constant inflow rate of gas. Temperature played a key role in the process and lower temper- ature in absorption tower was beneficial for reducing CO2 content. CO2 removal ratio could reach 24.4%-83.2% when CO2 content in the simulated gas was 25%-45%. The lowest CO2 content after absorption was 2.6% at 1.2 MPa with 400 L·h-1 gas flow and 200 L·h-1 water flow, which meets the requirement of CO2 content in natural Ras for vehicle fuel.展开更多
文摘The concept of Industrial Biosystems Engineering (IBsE) was suggested as a new engineering branch to be developed for meeting the needs for science, technology and professionals by the upcoming bioeconomy. With emphasis on systems, IBsE builds upon the interfaces between systems biology, bioprocessing, and systems engineering. This paper discussed the background, the suggested definition, the theoretical framework and methodologies of this new discipline as well as its challenges and future development.
基金Supported by The United States Department of Defense Breast Cancer Research Program,No.BC190820the National Institutes of Health,No.R01ES031322.
文摘Identifying the factors that contribute to individual susceptibility to cancer is essential for both prevention and treatment.The advancement of biotechnologies,particularly next-generation sequencing,has accelerated the discovery of genetic variants linked to cancer susceptibility.While hundreds of cancer-susceptibility genes have been identified,they only explain a small fraction of the overall cancer risk,a phenomenon known as"missing heritability".Despite progress,even considering factors such as epistasis,epigenetics,and gene-environment interactions,the missing heritability remains unresolved.Recent research has revealed that an individual's microbiome composition plays a significant role in cancer susceptibility through several mechanisms,such as modulating immune cell activity and influencing the presence or removal of environmental carcinogens.In this review,we examine the multifaceted roles of the microbiome in cancer risk and explore gene-microbiome and environment-microbiome interactions that may contribute to cancer susceptibility.Additionally,we highlight the importance of experimental models,such as collaborative cross mice,and advanced analytical tools,like artificial intelligence,in identifying microbial factors associated with cancer risk.Understanding these microbial determinants can open new avenues for interventions aimed at reducing cancer risk and guide the development of more effective cancer treatments.
文摘Humins,as a group of by-products formed through the condensation and coupling of fragment intermediates during lignocellulosic biomass refining,can cause numerous negative effects such as the wastage of carbon resources,clogging of reactor piping,deactivation of catalyst,and barriers to product separation.Elucidating the generation mechanism of humins,developing efficient inhibitors,and even utilizing them as a resource,both from the perspective of atom economy and safe production,constitutes a research endeavor replete with challenges and opportunities.Orbiting the critical issue of humins structure and its generation mechanism from cellulose and hemicellulose resources,the random condensation between intermediates such as 5-hydroxymethylfurfural,furfural,2,5-dioxo-6-hydroxyhexanal,and 1,2,4-benzenetriol etc.were systematically summarized.Additionally,the presence of lignin in real biorefining processes further promotes the formation of a special type of humins known as"pseudo-lignin".The influences of various factors,including raw materials,reaction temperature and time,acid-base environment,as well as solvent systems and catalysts,on the formation of humins were comprehensively analyzed.To minimize the formation of humins,the design of efficient solvent systems and catalysts is crucial.Furthermore,this review investigates the approaches to value-added applications of humins.The corresponding summary could provide guidance for the development of the humins chemistry.
基金Supported by the Scientific Research Projects of Jiangsu Provincial Health and Health Commission,No.ZDB2020034 and No.M2021056.
文摘BACKGROUND The understanding of bile acid(BA)and unsaturated fatty acid(UFA)profiles,as well as their dysregulation,remains elusive in individuals with type 2 diabetes mellitus(T2DM)coexisting with non-alcoholic fatty liver disease(NAFLD).Investigating these metabolites could offer valuable insights into the pathophy-siology of NAFLD in T2DM.AIM To identify potential metabolite biomarkers capable of distinguishing between NAFLD and T2DM.METHODS A training model was developed involving 399 participants,comprising 113 healthy controls(HCs),134 individuals with T2DM without NAFLD,and 152 individuals with T2DM and NAFLD.External validation encompassed 172 participants.NAFLD patients were divided based on liver fibrosis scores.The analytical approach employed univariate testing,orthogonal partial least squares-discriminant analysis,logistic regression,receiver operating characteristic curve analysis,and decision curve analysis to pinpoint and assess the diagnostic value of serum biomarkers.RESULTS Compared to HCs,both T2DM and NAFLD groups exhibited diminished levels of specific BAs.In UFAs,particular acids exhibited a positive correlation with NAFLD risk in T2DM,while theω-6:ω-3 UFA ratio demonstrated a negative correlation.Levels ofα-linolenic acid andγ-linolenic acid were linked to significant liver fibrosis in NAFLD.The validation cohort substantiated the predictive efficacy of these biomarkers for assessing NAFLD risk in T2DM patients.CONCLUSION This study underscores the connection between altered BA and UFA profiles and the presence of NAFLD in individuals with T2DM,proposing their potential as biomarkers in the pathogenesis of NAFLD.
文摘Peanuts pods grow underground and mature unevenly, resulting that choosing the correct time to harvest is more complicated than other crops. Pod maturity can be determined by blasting with a pressure washer to remove outer skin of the pod (exocarp) to expose the color of the middle layer (mesocarp). The mesocarp color changes with maturity from white to yellow, orange, brown and finally black. The sum of percentage from orange, brown, and black mesocarp (OBB) color and black color (BL) represents the kernels that are mature enough to harvest. The goal of this research is to identify methodologies to estimate OBB and BL of the pods using RGB images taken in the field and validate the proposed model using other pod images. The Mahalanobis distance classification method was used to process sets of images and calculate pod area (number of pixels) corresponding to two classes (mesocarp and background) with nine different color groups. The results showed a performance of 94% effectiveness for mesocarp using Mahalanobis distance classification. Statistical regression for OBB and BL was developed based on 315 images of peanut pods taken from the field. The R2 and root mean square error of predicted and actual OBB were 0.93 and 4.1%, respectively. The R2 and root mean square error of predicted and actual BL were 0.88 and 1.8%, respectively. The validation of OBB using other images provided reasonable estimation (R2 = 0.98 and RMSE = 2.73%). This study introduces a novel, cost-effective, and non-destructive method for estimating peanut maturity using RGB imagery and Mahalanobis distance classification in the field. This innovative approach addresses the limitations of traditional methods and offers a robust alternative for real-time maturity assessment.
基金supported by the Specialty Crops Research Initiative Award 2022-51181-38325 from the USDA National Institute of Food and Agriculture.
文摘The increasing use of traditional agricultural plastic mulch films(PMs)has raised significant environ-mental concerns,prompting the search for sustainable alternatives.Soil-biodegradable mulch films(BDMs)are often proposed as eco-friendly replacements;however,their widespread adoption remains contentious.This review employs a comparative life cycle assessment perspective to evaluate the environmental impact of PMs and BDMs across their production,use,and end-of-life stages,providing strategies to mitigate their impact on agroecosystems.BDMs generally exhibit lower energy use and greenhouse gas emissions than PMs but contribute to greater land-use demands.Reported eutrophica-tion and acidification potentials are less consistent,varying based on feedstock types and the scope of assessment of BDM,as well as the end-of-life management of PM.The environmental burden of both mulch types is influenced by the life cycle stage,polymer composition,farming practices,additives,film thickness,and local climatic conditions.The manufacturing stage is a major contributor to energy use and greenhouse gas emissions for both PMs and BDMs,despite their shared benefits of increasing crop yields.However,post-use impacts are more pronounced for PMs,driven by end-of-life strategy and adsorbed waste content.While starch-based BDMs offer a more sustainable alternative to PMs,un-certainties regarding the residence time of BDM residues in soil(albeit shorter than PM residues)and their effects on soil health,coupled with higher production costs,impede widespread adoption.For BDM end-of-life,soil biodegradation is recommended.Energy and material recovery options are crucial for PM end-of-life,with mechanical recycling preferred,although it requires addressing eutrophication and human toxicity.This review discusses these complexities within specific contexts and provides action-able insights to guide the sustainable integration of mulch films into agricultural practices.
基金supported by the National Natural Science Foundation of China(Grant No.U2233214,No.62250710166)supported by the University of Mannheim’s Graduate School of Economic and Social Sciences.We acknowledge the U.S.Department of Energy,the Office of Energy Efficiency&Renewable Energy Awards(DE-EE0009257)+1 种基金the United States Department of Agriculture,National Institute of Food and Agriculture Hatch/Multi State project 1017904the Bioproducts,Science and Engineering Laboratory,Department of Biological Systems Engineering at Washington State University.
文摘The aviation industry faces various challenges in meeting long-term sustainability goals amidst surging demand for air travel and growing environmental concerns of the general public.The year 2050 is set as an ambitious goal for net zero emissions,a substantial reduction in carbon dioxide emissions per passenger kilometer flown,major improvements in aircraft energy efficiency,and a development towards autonomous,intelligent operations.This review explores the pivotal role of advancements in engineering for achieving sustainability in aviation.Through a comprehensive review of existing literature and case studies,our work highlights how innovations in all aspects of aircraft engineering coupled with operations-related technologies,offer promising solutions to mitigate environmental impact,enhance efficiency,and ensure long-term sustainability in aviation operations.To discuss the necessary advances,we promote the so-called‘DESIGN and be SMART’framework,consisting of eleven complementary engineering challenges towards reaching sustainability.To address the high safety levels reached in air transportation,our DESIGN and be SMART framework also addresses the safety assurance challenge that is overarching each of the eleven engineering challenges.We believe that through an orchestrated integration of hardware advancements with innovative software solutions,and novel safety assurance methods,the aviation industry can realize synergistic benefits that drive sustainable growth of air transportation.Our review contributes to such an orchestration by describing the status quo and research challenges ahead.
基金Supported by a grant from the American College of Gastroenterology
文摘AIM： To investigate whether a fuzzy logic model could predict colorectal cancer （CRC） risk engendered by smoking in hereditary non-polyposis colorectal cancer （HNPCC） patients. METHODS： Three hundred and forty HNPCC mismatch repair （MMR） mutation carriers from the Creighton University Hereditary Cancer Institute Registry were selected for modeling. Age-dependent curves were generated to elucidate the joint effects between gene mutation （hMLH1 or hMSH2）, gender, and smoking status on the probability of developing CRC. RESULTS： Smoking significantly increased CRC risk in male hMSH2 mutation carriers （P 〈 0.05）. hMLH1 mutations augmented CRC risk relative to hMSH2 mutation carriers for males （P 〈 0.05）. Males had a significantly higher risk of CRC than females for hMLH1 non smokers （P 〈 0.05）, hMLH1 smokers （P 〈 0.1） and hMSH2 smokers （P 〈 0.1）. Smoking promoted CRC in a dose-dependent manner in hMSH2 in males （P 〈 0.05）. Females with hMSH2 mutations and both sexes with the hMLH1 groups only demonstrated a smoking effect after an extensive smoking history （P 〈 0.05）. CONCLUSION： CRC promotion by smoking in HNPCC patients is dependent on gene mutation, gender and age. These data demonstrate that fuzzy modeling may enable formulation of clinical risk scores, thereby allowing individualization of CRC prevention strategies.
基金Supported by the National High Technology Research and Development Program of China(2008AA062401)the China-US International Cooperation Project(2011DFA90800)the Ministry of Science and Technology,China
文摘Aqueous ammonia was used to pretreat wheat straw to improve biodegradability and provide nitrogen source for enhancing biogas production. Three doses of ammonia(2%, 4%, and 6%, dry matter) and three moisture contents(30%, 60%, and 80%, dry matter) were applied to pretreat wheat straw for 7 days. The pretreated wheat straws were anaerobically digested at three loading rates(50, 65, and 80 g·L-1) to produce biogas. The results indicated that the wheat straw pretreated with 80% moisture content and 4% ammonia achieved the highest methane yield of 199.7 ml·g-1(based on per unit volatile solids loaded), with shorter digestion time(T80) of 25 days at the loading rate of 65 g·L-1compared to untreated one. The main chemical compositions of wheat straw were also analyzed. The cellulose and hemicellulose contents were decomposed by 2%-20% and 26%-42%, respectively,while the lignin content was hardly removed, cold-water and hot-water extracts were increased by 4%-44%, and12%-52%, respectively, for the ammonia-pretreated wheat straws at different moisture contents. The appropriate C/N ratio and decomposition of original chemical compositions into relatively readily biodegradable substances will improve the biodegradability and biogas yield.
基金Supported by the National Technology Research and Development Program of China(2008AA062402)the China-US International Cooperation Project(2011DFA90800)the Ministry of Science and Technology,China
文摘CO2 removal from biogas by water washing system was investigated with various parameters, including liquid/ gas ratio, pressure, temperature, and CO2 content. The results indicate that CO2 removal ratio could reach 34.6%- 94.2% as liquid/gas ratio increased from 0.14 to 0.50. Increasing pressure （from 0.8 to 1.2 MPa） could improve gas purification with a constant inflow rate of gas. Temperature played a key role in the process and lower temper- ature in absorption tower was beneficial for reducing CO2 content. CO2 removal ratio could reach 24.4%-83.2% when CO2 content in the simulated gas was 25%-45%. The lowest CO2 content after absorption was 2.6% at 1.2 MPa with 400 L·h-1 gas flow and 200 L·h-1 water flow, which meets the requirement of CO2 content in natural Ras for vehicle fuel.
