The experimental study on the macro and micro characteristics of the spray from a pressure swirl nozzle embraces the growth of surface unstable wave,disintegration process,spray angle,breakup length and so on.The e...The experimental study on the macro and micro characteristics of the spray from a pressure swirl nozzle embraces the growth of surface unstable wave,disintegration process,spray angle,breakup length and so on.The effects of injection pressure,nozzle geometry and liquid properties on these characteristics are also discussed.The results are helpful to understand the underlying physics of the pressure swirl nozzle and serve as the basis for the practical design,usage and improvement of the nozzle.展开更多
Gas-bearing sediments are widely distributed in five continents all over the world.Most of the gases exist in the soil skeleton in the form of discrete large bubbles.The existence of gas-phase may increase or decrease...Gas-bearing sediments are widely distributed in five continents all over the world.Most of the gases exist in the soil skeleton in the form of discrete large bubbles.The existence of gas-phase may increase or decrease the strength of the soil skeleton.So far,bubbles’structural morphology and evolution characteristics in soil skeleton lack research,and the influence of different gas reservoir pressures on bubbles are still unclear.The micro characteristics of bubbles in the same sediment sample were studied using an industrial CT scanning test system to solve these problems.Using the image processing software,the micro variation characteristics of gas-bearing sediments in gas reservoir pressure change are obtained.The results show that the number and volume of bubbles in different equivalent radius ranges will change regularly under different gas reservoir pressure.With the increase of gas reservoir pressure,the number and volume of tiny bubbles decrease.In contrast,the number and volume of large bubbles increase,and the gas content in different positions increases and occupies a dominant position,driving the reduction of pore water and soil skeleton movement.展开更多
Micro turbine engine (MTE) is an important kind of propulsion system for miniature unmanned aircraft or missiles, because of its better high-speed performance (than propeller propulsion) and higher propulsion effi...Micro turbine engine (MTE) is an important kind of propulsion system for miniature unmanned aircraft or missiles, because of its better high-speed performance (than propeller propulsion) and higher propulsion efficiency (obviously than rockets). Windmill start is a common air-starting mode used in micro turbine engine. The windmill starting characteristics are important to the practical use of micro turbine engine. In this paper, the windmill starting characteristics research for a 12 cm diameter (MTE-D) micro turbine engine is carried out by experiment and numerical simulation. The characteristic of rotor mechanical losses at low-speed condition is stud- ied, and the engine common working line of windmill starting process is obtained. Based on the engine windmill characteristics, the propane ignition characteristics under different inflow conditions are researched, and the envelope of propane ignition and propane flameout is determined. The experimental research of fuel supply and ignition characteristics is completed, and the envelope of fuel supply and ignition is obtained. The windmill stage, propane ignition stage, fuel ignition stage and acceleration process from idling-speed to 80% full speed of MTE-D micro turbine engine is optimized, and the optimization windmill starting parameters are collected. The successful wind-mill starting experiment under this condition with engine speed up to 80% full speed indicates that these starting parameters are reasonable. All the starting parameters of MTE-D micro turbine engine obtained in this work are dimensionless parameters, and the conclusions obtained in this study have some reference to other micro turbine engines with the similar structural form and starting process.展开更多
Objective To explore the biological basis of the damp-heat stasis-toxin syndrome in colorectal cancer(CRC)patients.Methods Totally 100 patients with CRC and 50 healthy individuals were screened.A total of 41 patients ...Objective To explore the biological basis of the damp-heat stasis-toxin syndrome in colorectal cancer(CRC)patients.Methods Totally 100 patients with CRC and 50 healthy individuals were screened.A total of 41 patients with CRC with damp heat stasis syndrome(SRYD),41 patients with CRC without damp heat stasis syndrome(FSRYD)and 40 healthy individuals(Normal)were enrolled.16S rRNA sequencing technology was used to analyze the differences in the composition and diversity of microbial groups.Results There was no significant difference in richness and diversity among SRYD,FSRYD and Normal groups.Compared with other groups,different expressions ofFirmicutes,Actinobacteriota,Elusimicrobiota,RCP2-54 at phylum level,Ralstonia,Sphingomonas,Dialister,Corynebacterium,Rothia,Odoribacter,Streptococcus and so on at genus level were detected in SRYDD groups.A possible noninvasive biomarker of damp-heat stasis andtoxin syndrome in colorectal cancer may be Streptococcus.LEfSe analysis indicated a ggreaterabundanceof Firmicutes,Actinobacteriota,Streptococcaceae,Streptococcus,Actinobacteria,Granulicatella,Rothia,Corynebacteriales,Corynebacteriaceae,Corynebacterium in SRYD groups.PICRUSt functional predictive analysis indicated the primary enrichment pathway of the SRYD group's differential expression are phosphotransferase system,valine,leucine and isoleucine degradation,central carbon metabolism in cancer,carbohydrate transport and metabolism.Conclusion It is reasonable to analyze CRC Chinese medicine syndrome differentiation from the perspective of tongue coating flora.Tongue coating flora can be used to diagnose damp-heat stasis-toxin syndrome in CRC patients.Streptococcus could be a noninvasive biomarker for damp-heat stasis-toxin syndrome in CRC.展开更多
文摘The experimental study on the macro and micro characteristics of the spray from a pressure swirl nozzle embraces the growth of surface unstable wave,disintegration process,spray angle,breakup length and so on.The effects of injection pressure,nozzle geometry and liquid properties on these characteristics are also discussed.The results are helpful to understand the underlying physics of the pressure swirl nozzle and serve as the basis for the practical design,usage and improvement of the nozzle.
基金The Shandong Joint Funds of National Natural Science Foundation of China under contract No.U2006213the Fundamental Research Funds for the Central Universities under contract No.201962011the Grant of Laboratory for Marine Geology,Pilot National Laboratory for Marine Science and Technology(Qingdao)under contract No.MGQNLM-KF201804。
文摘Gas-bearing sediments are widely distributed in five continents all over the world.Most of the gases exist in the soil skeleton in the form of discrete large bubbles.The existence of gas-phase may increase or decrease the strength of the soil skeleton.So far,bubbles’structural morphology and evolution characteristics in soil skeleton lack research,and the influence of different gas reservoir pressures on bubbles are still unclear.The micro characteristics of bubbles in the same sediment sample were studied using an industrial CT scanning test system to solve these problems.Using the image processing software,the micro variation characteristics of gas-bearing sediments in gas reservoir pressure change are obtained.The results show that the number and volume of bubbles in different equivalent radius ranges will change regularly under different gas reservoir pressure.With the increase of gas reservoir pressure,the number and volume of tiny bubbles decrease.In contrast,the number and volume of large bubbles increase,and the gas content in different positions increases and occupies a dominant position,driving the reduction of pore water and soil skeleton movement.
文摘Micro turbine engine (MTE) is an important kind of propulsion system for miniature unmanned aircraft or missiles, because of its better high-speed performance (than propeller propulsion) and higher propulsion efficiency (obviously than rockets). Windmill start is a common air-starting mode used in micro turbine engine. The windmill starting characteristics are important to the practical use of micro turbine engine. In this paper, the windmill starting characteristics research for a 12 cm diameter (MTE-D) micro turbine engine is carried out by experiment and numerical simulation. The characteristic of rotor mechanical losses at low-speed condition is stud- ied, and the engine common working line of windmill starting process is obtained. Based on the engine windmill characteristics, the propane ignition characteristics under different inflow conditions are researched, and the envelope of propane ignition and propane flameout is determined. The experimental research of fuel supply and ignition characteristics is completed, and the envelope of fuel supply and ignition is obtained. The windmill stage, propane ignition stage, fuel ignition stage and acceleration process from idling-speed to 80% full speed of MTE-D micro turbine engine is optimized, and the optimization windmill starting parameters are collected. The successful wind-mill starting experiment under this condition with engine speed up to 80% full speed indicates that these starting parameters are reasonable. All the starting parameters of MTE-D micro turbine engine obtained in this work are dimensionless parameters, and the conclusions obtained in this study have some reference to other micro turbine engines with the similar structural form and starting process.
文摘Objective To explore the biological basis of the damp-heat stasis-toxin syndrome in colorectal cancer(CRC)patients.Methods Totally 100 patients with CRC and 50 healthy individuals were screened.A total of 41 patients with CRC with damp heat stasis syndrome(SRYD),41 patients with CRC without damp heat stasis syndrome(FSRYD)and 40 healthy individuals(Normal)were enrolled.16S rRNA sequencing technology was used to analyze the differences in the composition and diversity of microbial groups.Results There was no significant difference in richness and diversity among SRYD,FSRYD and Normal groups.Compared with other groups,different expressions ofFirmicutes,Actinobacteriota,Elusimicrobiota,RCP2-54 at phylum level,Ralstonia,Sphingomonas,Dialister,Corynebacterium,Rothia,Odoribacter,Streptococcus and so on at genus level were detected in SRYDD groups.A possible noninvasive biomarker of damp-heat stasis andtoxin syndrome in colorectal cancer may be Streptococcus.LEfSe analysis indicated a ggreaterabundanceof Firmicutes,Actinobacteriota,Streptococcaceae,Streptococcus,Actinobacteria,Granulicatella,Rothia,Corynebacteriales,Corynebacteriaceae,Corynebacterium in SRYD groups.PICRUSt functional predictive analysis indicated the primary enrichment pathway of the SRYD group's differential expression are phosphotransferase system,valine,leucine and isoleucine degradation,central carbon metabolism in cancer,carbohydrate transport and metabolism.Conclusion It is reasonable to analyze CRC Chinese medicine syndrome differentiation from the perspective of tongue coating flora.Tongue coating flora can be used to diagnose damp-heat stasis-toxin syndrome in CRC patients.Streptococcus could be a noninvasive biomarker for damp-heat stasis-toxin syndrome in CRC.