Fermented sour soup is a unique traditional sour food of the Miao and Dong ethnic groups in China.However,due to the commonly used traditional fermentation,the unstable fluctuation of microbial community often leads t...Fermented sour soup is a unique traditional sour food of the Miao and Dong ethnic groups in China.However,due to the commonly used traditional fermentation,the unstable fluctuation of microbial community often leads to some unpleasant inherent off-flavours in rice sour soup.In this study,the microbial composition and volatile flavour components of off-flavour and normal rice sour soup were examined by high-throughput sequencing and headspace solid-phase microextraction coupled with gas chromatography mass spectrometry.Then,based on Pearson correlation coefficients,the correlations between fungi and bacteria and those between core microorganisms and key volatile flavour components were investigated.The dominant fungal genera included Candida,Dekkera,Pichia,Rhizopus,and Issatchenkia,whereas the dominant bacterial genera included Lactobacillus,Pectinatus,Bifidobacterium,Pseudomonas,and Acetobacter.Compared to normal rice sour soup,off-flavoured rice sour soup contained the significantly increased relative abundance of Candida and the significantly decreased relative abundance of Dkkera.In addition,80 volatile flavour compounds detected in off-flavoured rice sour soup,mainly including esters,acids,and alcohols,were different from those detected in normal rice sour soup.Especially,some substances were only detected in off-flavoured rice sour soup,such as 1-hexanol(68-207μg/kg),butyric acid(20-92μg/kg)and heptanoic acid(12-45μg/kg),which might be the main source of off-flavours.These results provide new ideas and strategies of removing or abating odour from fermented rice sour soup.展开更多
While most mammals find highly acidic foods aversive,many bird species have evolved remarkable tolerance for sour fruits-a crucial adaptation that has opened new ecological niches.Wild fruits can contain organic acid ...While most mammals find highly acidic foods aversive,many bird species have evolved remarkable tolerance for sour fruits-a crucial adaptation that has opened new ecological niches.Wild fruits can contain organic acid concentrations dozens of times higher than cultivated varieties,yet species like the redwing(Turdus iliacus)and black grouse(Tetrao tetrix)have evolved to actually prefer these acidic foods as dietary staples.展开更多
The construction and operation of sulfur-containing gas storage are often more difficult than a non-sulfur storage facility due to the need to prevent environmental contamination from H_(2)S leaks,as well as the corro...The construction and operation of sulfur-containing gas storage are often more difficult than a non-sulfur storage facility due to the need to prevent environmental contamination from H_(2)S leaks,as well as the corrosive effects of H_(2)S on production facilities.Rapid elutriation of H_(2)S from the reservoir during the construction of the gas storage is an effective way to avoid these problems.However,the existing H_(2)S elutriation method has low efficiency and high economic cost,which limits the development of reconstructed gas storage of sulfur-containing gas reservoirs.To improve the efficiency of H_(2)S elutriation in sulfur-containing gas reservoirs and enhance the economic benefits,a numerical simulation model of multiphase flow components was established to study the migration law of H_(2)S in the multi-cycle operation of gas storage.Based on the H_(2)S migrate law,the displacement H_(2)S elutriation method was developed,and the elutriation mechanism and elutriation efficiency of the two methods were compared and analyzed.In addition,the main controlling factors affecting the H_(2)S elutriation efficiency were investigated,and the H_(2)S elutriation scheme of H gas storage was optimized.The results indicate that H_(2)S migrates between near-well and far-well regions under pressure differentials.The traditional H_(2)S elutriation method relies on concentration gradient diffusion,whereas the displacement elutriation approach leverages pressure differentials with higher H_(2)S elutriation efficiency.For the displacement elutriation method,higher reservoir permeability enhances the peak-shaving capacity of the gas storage but has a minor impact on H_(2)S elutriation when the formation permeability is between 30 and 100 mD.The elutriation efficiency is significantly higher when wells are drilled in the high structural parts of the reservoir compared to the low structural parts.Longer displacement elutriation time within a cycle improves H_(2)S elutriation efficiency but reduces the working gas volume of the storage.Therefore,the optimal displacement time for H gas storage is 60 days.An optimized H_(2)S elutriation scheme enabled the working gas to meet the national first-class natural gas standard within 10 cycles.This study elucidates H_(2)S migration patterns,H_(2)S elutriation mechanisms,and key influence factors on H_(2)S elutriation efficiency,offering valuable technical insights for sour gas storage operations.展开更多
为了研究低DO下负荷对污泥膨胀的影响,采用SBR反应器,在DO〈0.5 mg.L-1,pH 7.2~8.0,温度（23±0.5）℃,MLSS 3000~3500 mg.L-1,负荷分别为0.22、0.44、0.66 g COD.（g MLSS）-1.d-1的条件下,研究不同负荷下的SVI变化趋势、污泥膨胀...为了研究低DO下负荷对污泥膨胀的影响,采用SBR反应器,在DO〈0.5 mg.L-1,pH 7.2~8.0,温度（23±0.5）℃,MLSS 3000~3500 mg.L-1,负荷分别为0.22、0.44、0.66 g COD.（g MLSS）-1.d-1的条件下,研究不同负荷下的SVI变化趋势、污泥膨胀类型、引发原因、耗氧速率、脱氮除磷效果与同步硝化反硝化率。结果显示,低DO下（〈0.5 mg.L-1）,负荷0.22 g COD.（g MLSS）-1.d-1时未发生污泥膨胀,随着负荷升高,污泥沉降性恶化加快。并且不同负荷引发的污泥膨胀类型不同,在负荷0.66 g COD.（g MLSS）-1.d-1时发生黏性膨胀,而负荷0.44 g COD.（g MLSS）-1.d-1时发生丝状菌微膨胀。黏性膨胀时出水氨氮及磷去除效果变差,但丝状菌膨胀时出水水质并没有受到影响,且比吸磷速率更快,出水SS更低。未发生污泥膨胀时同步硝化反硝化率最大,丝状菌膨胀时次之,黏性膨胀时最小。SOUR过高时,很可能伴随着污泥沉降性变差和出水水质恶化。展开更多
研究了序批式反应器(SBR)内好氧颗粒污泥在不同有机负荷(1.6 kg COD/(m3.d)和8 kg COD/(m3.d))和不同含盐(2.5%和5.0%)条件下胞外聚合物(EPS)的变化情况,并对EPS、比耗氧速率(SOUR)和孔隙率之间的关系作了进一步探讨。结果表明:在SBR反...研究了序批式反应器(SBR)内好氧颗粒污泥在不同有机负荷(1.6 kg COD/(m3.d)和8 kg COD/(m3.d))和不同含盐(2.5%和5.0%)条件下胞外聚合物(EPS)的变化情况,并对EPS、比耗氧速率(SOUR)和孔隙率之间的关系作了进一步探讨。结果表明:在SBR反应器中,负荷较含盐量对好氧颗粒污泥EPS变化的影响要显著,且EPS糖成分和SOUR之间、EPS蛋白成分和孔隙率之间均呈负相关。另外,高负荷条件下的系统稳定性要优于低负荷。展开更多
基金funded by National Natural Science Foundation of China(32360568)Science and Technology Plan Project of Guizhou Province(Qian Ke He Chengguo[2023]Zhongda 011)+2 种基金Guizhou Basic Research Program(Natural Science)Mianshang Project(Qiankehe Basic MS[2025]671)Guizhou Provincial Association of Science and Technology Youth Science and Technology Talent Support Project(GASTYESS202407)Guizhou University Natural Science Specialized(Te Gang)Scientific Research Fund(Gui Da Te Gang He Zi(2022)39).
文摘Fermented sour soup is a unique traditional sour food of the Miao and Dong ethnic groups in China.However,due to the commonly used traditional fermentation,the unstable fluctuation of microbial community often leads to some unpleasant inherent off-flavours in rice sour soup.In this study,the microbial composition and volatile flavour components of off-flavour and normal rice sour soup were examined by high-throughput sequencing and headspace solid-phase microextraction coupled with gas chromatography mass spectrometry.Then,based on Pearson correlation coefficients,the correlations between fungi and bacteria and those between core microorganisms and key volatile flavour components were investigated.The dominant fungal genera included Candida,Dekkera,Pichia,Rhizopus,and Issatchenkia,whereas the dominant bacterial genera included Lactobacillus,Pectinatus,Bifidobacterium,Pseudomonas,and Acetobacter.Compared to normal rice sour soup,off-flavoured rice sour soup contained the significantly increased relative abundance of Candida and the significantly decreased relative abundance of Dkkera.In addition,80 volatile flavour compounds detected in off-flavoured rice sour soup,mainly including esters,acids,and alcohols,were different from those detected in normal rice sour soup.Especially,some substances were only detected in off-flavoured rice sour soup,such as 1-hexanol(68-207μg/kg),butyric acid(20-92μg/kg)and heptanoic acid(12-45μg/kg),which might be the main source of off-flavours.These results provide new ideas and strategies of removing or abating odour from fermented rice sour soup.
文摘While most mammals find highly acidic foods aversive,many bird species have evolved remarkable tolerance for sour fruits-a crucial adaptation that has opened new ecological niches.Wild fruits can contain organic acid concentrations dozens of times higher than cultivated varieties,yet species like the redwing(Turdus iliacus)and black grouse(Tetrao tetrix)have evolved to actually prefer these acidic foods as dietary staples.
基金supported by the Science and Technology Research Program of Chongqing Municipal Education Commission(KJQN202401501,KJZD-M202401501).
文摘The construction and operation of sulfur-containing gas storage are often more difficult than a non-sulfur storage facility due to the need to prevent environmental contamination from H_(2)S leaks,as well as the corrosive effects of H_(2)S on production facilities.Rapid elutriation of H_(2)S from the reservoir during the construction of the gas storage is an effective way to avoid these problems.However,the existing H_(2)S elutriation method has low efficiency and high economic cost,which limits the development of reconstructed gas storage of sulfur-containing gas reservoirs.To improve the efficiency of H_(2)S elutriation in sulfur-containing gas reservoirs and enhance the economic benefits,a numerical simulation model of multiphase flow components was established to study the migration law of H_(2)S in the multi-cycle operation of gas storage.Based on the H_(2)S migrate law,the displacement H_(2)S elutriation method was developed,and the elutriation mechanism and elutriation efficiency of the two methods were compared and analyzed.In addition,the main controlling factors affecting the H_(2)S elutriation efficiency were investigated,and the H_(2)S elutriation scheme of H gas storage was optimized.The results indicate that H_(2)S migrates between near-well and far-well regions under pressure differentials.The traditional H_(2)S elutriation method relies on concentration gradient diffusion,whereas the displacement elutriation approach leverages pressure differentials with higher H_(2)S elutriation efficiency.For the displacement elutriation method,higher reservoir permeability enhances the peak-shaving capacity of the gas storage but has a minor impact on H_(2)S elutriation when the formation permeability is between 30 and 100 mD.The elutriation efficiency is significantly higher when wells are drilled in the high structural parts of the reservoir compared to the low structural parts.Longer displacement elutriation time within a cycle improves H_(2)S elutriation efficiency but reduces the working gas volume of the storage.Therefore,the optimal displacement time for H gas storage is 60 days.An optimized H_(2)S elutriation scheme enabled the working gas to meet the national first-class natural gas standard within 10 cycles.This study elucidates H_(2)S migration patterns,H_(2)S elutriation mechanisms,and key influence factors on H_(2)S elutriation efficiency,offering valuable technical insights for sour gas storage operations.
文摘为了研究低DO下负荷对污泥膨胀的影响,采用SBR反应器,在DO〈0.5 mg.L-1,pH 7.2~8.0,温度（23±0.5）℃,MLSS 3000~3500 mg.L-1,负荷分别为0.22、0.44、0.66 g COD.（g MLSS）-1.d-1的条件下,研究不同负荷下的SVI变化趋势、污泥膨胀类型、引发原因、耗氧速率、脱氮除磷效果与同步硝化反硝化率。结果显示,低DO下（〈0.5 mg.L-1）,负荷0.22 g COD.（g MLSS）-1.d-1时未发生污泥膨胀,随着负荷升高,污泥沉降性恶化加快。并且不同负荷引发的污泥膨胀类型不同,在负荷0.66 g COD.（g MLSS）-1.d-1时发生黏性膨胀,而负荷0.44 g COD.（g MLSS）-1.d-1时发生丝状菌微膨胀。黏性膨胀时出水氨氮及磷去除效果变差,但丝状菌膨胀时出水水质并没有受到影响,且比吸磷速率更快,出水SS更低。未发生污泥膨胀时同步硝化反硝化率最大,丝状菌膨胀时次之,黏性膨胀时最小。SOUR过高时,很可能伴随着污泥沉降性变差和出水水质恶化。
文摘研究了序批式反应器(SBR)内好氧颗粒污泥在不同有机负荷(1.6 kg COD/(m3.d)和8 kg COD/(m3.d))和不同含盐(2.5%和5.0%)条件下胞外聚合物(EPS)的变化情况,并对EPS、比耗氧速率(SOUR)和孔隙率之间的关系作了进一步探讨。结果表明:在SBR反应器中,负荷较含盐量对好氧颗粒污泥EPS变化的影响要显著,且EPS糖成分和SOUR之间、EPS蛋白成分和孔隙率之间均呈负相关。另外,高负荷条件下的系统稳定性要优于低负荷。
