特殊螺纹接头油套管油田验收公差的确定一直是油田和生产厂家争议的焦点。为解决特殊螺纹接头螺纹参数验收公差无科学计算方法的问题,根据尺寸链理论及统计学公差分析方法建立了一种特殊螺纹接头油套管螺纹顶径验收公差的确定方法,并以...特殊螺纹接头油套管油田验收公差的确定一直是油田和生产厂家争议的焦点。为解决特殊螺纹接头螺纹参数验收公差无科学计算方法的问题,根据尺寸链理论及统计学公差分析方法建立了一种特殊螺纹接头油套管螺纹顶径验收公差的确定方法,并以某扣型Φ88.90 mm×7.34 mm C110特殊螺纹油管为例,通过螺纹生产各阶段接箍螺纹顶径的统计分析,计算出该油管接箍螺纹顶径验收公差为±0.06 mm。研究成果为特殊螺纹接头油套管验收公差的确定提供了技术支持,对油田提高特殊螺纹接头油套管入库验收和质量控制水平具有指导意义。展开更多
One of the goals of grazing management in the desert steppe is to improve its ecosystem.However,relatively little is known about soil microbe communities in the desert steppe ecosystem under grazing management.In this...One of the goals of grazing management in the desert steppe is to improve its ecosystem.However,relatively little is known about soil microbe communities in the desert steppe ecosystem under grazing management.In this study,we investigated the diversity and aboveground biomass of Caragana korshinskii Kom.shrub communities in long-term fencing and grazing areas,combined with an analysis of soil physical-chemical properties and genomics,with the aim of understanding how fence management affects plant-soil-microbial inter-relationships in the desert steppe,China.The results showed that fence management(exclosure)increased plant diversity and aboveground biomass in C.korshinskii shrub area and effectively enhanced soil organic carbon(233.94%),available nitrogen(87.77%),and available phosphorus(53.67%)contents.As well,the Shannon indices of soil bacteria and fungi were greater in the fenced plot.Plant-soil changes profoundly affected the alpha-and beta-diversity of soil bacteria.Fence management also altered the soil microbial community structure,significantly increasing the relative abundances of Acidobacteriota(5.31%-8.99%),Chloroflexi(3.99%-5.58%),and Glomeromycota(1.37%-3.28%).The soil bacterial-fungal co-occurrence networks under fence management had higher complexity and connectivity.Based on functional predictions,fence management significantly increased the relative abundance of bacteria with nitrification and nitrate reduction functions and decreased the relative abundance of bacteria with nitrate and nitrite respiration functions.The relative abundances of ecologically functional fungi with arbuscular mycorrhizal fungi,ectomycorrhizal fungi,and saprotrophs also significantly increased under fence management.In addition,the differential functional groups of bacteria and fungi were closely related to plant-soil changes.The results of this study have significant positive implications for the ecological restoration and reconstruction of dry desert steppe and similar areas.展开更多
文摘特殊螺纹接头油套管油田验收公差的确定一直是油田和生产厂家争议的焦点。为解决特殊螺纹接头螺纹参数验收公差无科学计算方法的问题,根据尺寸链理论及统计学公差分析方法建立了一种特殊螺纹接头油套管螺纹顶径验收公差的确定方法,并以某扣型Φ88.90 mm×7.34 mm C110特殊螺纹油管为例,通过螺纹生产各阶段接箍螺纹顶径的统计分析,计算出该油管接箍螺纹顶径验收公差为±0.06 mm。研究成果为特殊螺纹接头油套管验收公差的确定提供了技术支持,对油田提高特殊螺纹接头油套管入库验收和质量控制水平具有指导意义。
基金funded by the National Natural Science Foundation of China(32061123006,32360426).
文摘One of the goals of grazing management in the desert steppe is to improve its ecosystem.However,relatively little is known about soil microbe communities in the desert steppe ecosystem under grazing management.In this study,we investigated the diversity and aboveground biomass of Caragana korshinskii Kom.shrub communities in long-term fencing and grazing areas,combined with an analysis of soil physical-chemical properties and genomics,with the aim of understanding how fence management affects plant-soil-microbial inter-relationships in the desert steppe,China.The results showed that fence management(exclosure)increased plant diversity and aboveground biomass in C.korshinskii shrub area and effectively enhanced soil organic carbon(233.94%),available nitrogen(87.77%),and available phosphorus(53.67%)contents.As well,the Shannon indices of soil bacteria and fungi were greater in the fenced plot.Plant-soil changes profoundly affected the alpha-and beta-diversity of soil bacteria.Fence management also altered the soil microbial community structure,significantly increasing the relative abundances of Acidobacteriota(5.31%-8.99%),Chloroflexi(3.99%-5.58%),and Glomeromycota(1.37%-3.28%).The soil bacterial-fungal co-occurrence networks under fence management had higher complexity and connectivity.Based on functional predictions,fence management significantly increased the relative abundance of bacteria with nitrification and nitrate reduction functions and decreased the relative abundance of bacteria with nitrate and nitrite respiration functions.The relative abundances of ecologically functional fungi with arbuscular mycorrhizal fungi,ectomycorrhizal fungi,and saprotrophs also significantly increased under fence management.In addition,the differential functional groups of bacteria and fungi were closely related to plant-soil changes.The results of this study have significant positive implications for the ecological restoration and reconstruction of dry desert steppe and similar areas.
