This study investigated the effects of salt(3%and 6%,m/m)and rice flour(10%and 20%,m/m)addition in sour meat,a traditional Chinese fermented meat.It was found that salt has greater effect than rice flour addition in s...This study investigated the effects of salt(3%and 6%,m/m)and rice flour(10%and 20%,m/m)addition in sour meat,a traditional Chinese fermented meat.It was found that salt has greater effect than rice flour addition in spontaneous fermentation.Low-salt groups had lower pH and higher titratable total acid.In the low-salt groups,the dominant genera were Lactobacillus and Lactococcus,whereas Staphylococcus,Weissella,and Tetragenococcus were dominant in the high-salt groups.Higher total free amino acids and essential amino acids,organic acids,hexanoic acid ethyl ester and octanoic acid ethyl ester were found in the low-salt groups.The RDA analysis revealed that Lactococcus was closely related to product quality,with the S3F10(3%salt and 10%rice f lour)group outperforming the others in the sensory evaluation.Therefore,3%salt and 10%rice flour were considered more appropriate for the production of healthy and tasty fermented sour meats.展开更多
Based on the new data of drilling, seismic, logging, test and experiments, the key scientific problems in reservoir formation, hydrocarbon accumulation and efficient oil and gas development methods of deep and ultra-d...Based on the new data of drilling, seismic, logging, test and experiments, the key scientific problems in reservoir formation, hydrocarbon accumulation and efficient oil and gas development methods of deep and ultra-deep marine carbonate strata in the central and western superimposed basin in China have been continuously studied.(1) The fault-controlled carbonate reservoir and the ancient dolomite reservoir are two important types of reservoirs in the deep and ultra-deep marine carbonates. According to the formation origin, the large-scale fault-controlled reservoir can be further divided into three types:fracture-cavity reservoir formed by tectonic rupture, fault and fluid-controlled reservoir, and shoal and mound reservoir modified by fault and fluid. The Sinian microbial dolomites are developed in the aragonite-dolomite sea. The predominant mound-shoal facies, early dolomitization and dissolution, acidic fluid environment, anhydrite capping and overpressure are the key factors for the formation and preservation of high-quality dolomite reservoirs.(2) The organic-rich shale of the marine carbonate strata in the superimposed basins of central and western China are mainly developed in the sedimentary environments of deep-water shelf of passive continental margin and carbonate ramp. The tectonic-thermal system is the important factor controlling the hydrocarbon phase in deep and ultra-deep reservoirs, and the reformed dynamic field controls oil and gas accumulation and distribution in deep and ultra-deep marine carbonates.(3) During the development of high-sulfur gas fields such as Puguang, sulfur precipitation blocks the wellbore. The application of sulfur solvent combined with coiled tubing has a significant effect on removing sulfur blockage. The integrated technology of dual-medium modeling and numerical simulation based on sedimentary simulation can accurately characterize the spatial distribution and changes of the water invasion front.Afterward, water control strategies for the entire life cycle of gas wells are proposed, including flow rate management, water drainage and plugging.(4) In the development of ultra-deep fault-controlled fractured-cavity reservoirs, well production declines rapidly due to the permeability reduction, which is a consequence of reservoir stress-sensitivity. The rapid phase change in condensate gas reservoir and pressure decline significantly affect the recovery of condensate oil. Innovative development methods such as gravity drive through water and natural gas injection, and natural gas drive through top injection and bottom production for ultra-deep fault-controlled condensate gas reservoirs are proposed. By adopting the hierarchical geological modeling and the fluid-solid-thermal coupled numerical simulation, the accuracy of producing performance prediction in oil and gas reservoirs has been effectively improved.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supported by the National Key Research and Development Project(2022YFD2100902)National Natural Science Foundation of China(32372363)+1 种基金Dalian High-level Talent Innovation Support Program(2021RQ093)the Basic Research Project of Education Department of Liaoning Province(LJKZ0544).
文摘This study investigated the effects of salt(3%and 6%,m/m)and rice flour(10%and 20%,m/m)addition in sour meat,a traditional Chinese fermented meat.It was found that salt has greater effect than rice flour addition in spontaneous fermentation.Low-salt groups had lower pH and higher titratable total acid.In the low-salt groups,the dominant genera were Lactobacillus and Lactococcus,whereas Staphylococcus,Weissella,and Tetragenococcus were dominant in the high-salt groups.Higher total free amino acids and essential amino acids,organic acids,hexanoic acid ethyl ester and octanoic acid ethyl ester were found in the low-salt groups.The RDA analysis revealed that Lactococcus was closely related to product quality,with the S3F10(3%salt and 10%rice f lour)group outperforming the others in the sensory evaluation.Therefore,3%salt and 10%rice flour were considered more appropriate for the production of healthy and tasty fermented sour meats.
基金Supported by the National Natural Science Foundation of ChinaCorporate Innovative Development Joint Fund(U19B6003)。
文摘Based on the new data of drilling, seismic, logging, test and experiments, the key scientific problems in reservoir formation, hydrocarbon accumulation and efficient oil and gas development methods of deep and ultra-deep marine carbonate strata in the central and western superimposed basin in China have been continuously studied.(1) The fault-controlled carbonate reservoir and the ancient dolomite reservoir are two important types of reservoirs in the deep and ultra-deep marine carbonates. According to the formation origin, the large-scale fault-controlled reservoir can be further divided into three types:fracture-cavity reservoir formed by tectonic rupture, fault and fluid-controlled reservoir, and shoal and mound reservoir modified by fault and fluid. The Sinian microbial dolomites are developed in the aragonite-dolomite sea. The predominant mound-shoal facies, early dolomitization and dissolution, acidic fluid environment, anhydrite capping and overpressure are the key factors for the formation and preservation of high-quality dolomite reservoirs.(2) The organic-rich shale of the marine carbonate strata in the superimposed basins of central and western China are mainly developed in the sedimentary environments of deep-water shelf of passive continental margin and carbonate ramp. The tectonic-thermal system is the important factor controlling the hydrocarbon phase in deep and ultra-deep reservoirs, and the reformed dynamic field controls oil and gas accumulation and distribution in deep and ultra-deep marine carbonates.(3) During the development of high-sulfur gas fields such as Puguang, sulfur precipitation blocks the wellbore. The application of sulfur solvent combined with coiled tubing has a significant effect on removing sulfur blockage. The integrated technology of dual-medium modeling and numerical simulation based on sedimentary simulation can accurately characterize the spatial distribution and changes of the water invasion front.Afterward, water control strategies for the entire life cycle of gas wells are proposed, including flow rate management, water drainage and plugging.(4) In the development of ultra-deep fault-controlled fractured-cavity reservoirs, well production declines rapidly due to the permeability reduction, which is a consequence of reservoir stress-sensitivity. The rapid phase change in condensate gas reservoir and pressure decline significantly affect the recovery of condensate oil. Innovative development methods such as gravity drive through water and natural gas injection, and natural gas drive through top injection and bottom production for ultra-deep fault-controlled condensate gas reservoirs are proposed. By adopting the hierarchical geological modeling and the fluid-solid-thermal coupled numerical simulation, the accuracy of producing performance prediction in oil and gas reservoirs has been effectively improved.
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。