It is important and profound to quantitatively study the relation between rheology and microstructure for development of the microstructural mechanism of crude oil rheology and even for the waxy crude oil pipelining.H...It is important and profound to quantitatively study the relation between rheology and microstructure for development of the microstructural mechanism of crude oil rheology and even for the waxy crude oil pipelining.However,due to the high complexity and irregularity of wax crystal morphology,quantitative characterization is hard to achieve.This has hampered further study on the rheology-microstructure relationship.A new approach combined the fractal geometry and the stereology theory is presented for quantifying the intricate wax crystal morphology and structure.Based on the characterization,the effects of microstructures and oil composition on the waxy crude viscosities are analyzed quantitatively.It further validates the previous qualitative research and enriches understanding into the microstructural mechanism of waxy crude oil rheology.展开更多
The results of quantitative characters for anatomy in stems of three varieties tomatoes seedlings showed that the cell population between vascular bundle and epidermis, the cellular layers among vascular bundles and t...The results of quantitative characters for anatomy in stems of three varieties tomatoes seedlings showed that the cell population between vascular bundle and epidermis, the cellular layers among vascular bundles and the cell population in an unit area （mm^2） of no vascular bundle areas were similar and there had small difference among three varieties. On the foundation of these studies, the developmental mechanism of tomato seedling stem was discussed.展开更多
基于湖泊碎屑堆积反演湖泊环境演化是干旱、半干旱地区全球变化研究的主要内容之一。但是大部分指标方法仅具有定性特点且敏感程度受制于背景环境等因素,影响了对湖泊环境演变与水文气候变化过程的深入了解。因此,从结构涌现秩序的理念...基于湖泊碎屑堆积反演湖泊环境演化是干旱、半干旱地区全球变化研究的主要内容之一。但是大部分指标方法仅具有定性特点且敏感程度受制于背景环境等因素,影响了对湖泊环境演变与水文气候变化过程的深入了解。因此,从结构涌现秩序的理念出发,基于粒度参数指标体系,开发了可用于描述体系结构演化的指标——体系结构量化指数(又称结构异常指数),尝试重建东亚季风边缘区农牧交错带封闭湖泊黄旗海约3 600~1 500 cal a BP年间湖面水位波动。结果显示,在轨道驱动的夏季太阳辐射降低的背景下,黄旗海湖面逐渐降低,期间存在百年尺度的剧烈波动。与基于孢粉重建的山西公海降水量、贵州董哥洞和湖北和尚洞等洞穴石笋氧同位素记录,以及ENSO活跃程度等记录对比分析发现,这种百年尺度的波动与太阳活动驱动的亚洲季风区夏季风降水和ENSO活动密切相关。太阳辐射减弱、夏季风降水减弱、ENSO活动增强,反之亦然。本研究揭示了太阳活动与ENSO、夏季风强度之间的关系,验证了湖泊碎屑沉积结构异常指数能在百年-千年尺度上较好地反演封闭湖泊水位变化。从已有的研究推断,这种反演具有定量属性,这对于内陆湖泊全球变化研究具有重要意义。展开更多
文摘It is important and profound to quantitatively study the relation between rheology and microstructure for development of the microstructural mechanism of crude oil rheology and even for the waxy crude oil pipelining.However,due to the high complexity and irregularity of wax crystal morphology,quantitative characterization is hard to achieve.This has hampered further study on the rheology-microstructure relationship.A new approach combined the fractal geometry and the stereology theory is presented for quantifying the intricate wax crystal morphology and structure.Based on the characterization,the effects of microstructures and oil composition on the waxy crude viscosities are analyzed quantitatively.It further validates the previous qualitative research and enriches understanding into the microstructural mechanism of waxy crude oil rheology.
基金Supported by Committee of Nature Science Foundation of Heilongjiang Province (C2005-32)Post-doctoral Science Committee of China (LRB04-217)Scientific Research Start Committee of Northeast Agricultural University
文摘The results of quantitative characters for anatomy in stems of three varieties tomatoes seedlings showed that the cell population between vascular bundle and epidermis, the cellular layers among vascular bundles and the cell population in an unit area （mm^2） of no vascular bundle areas were similar and there had small difference among three varieties. On the foundation of these studies, the developmental mechanism of tomato seedling stem was discussed.
文摘基于湖泊碎屑堆积反演湖泊环境演化是干旱、半干旱地区全球变化研究的主要内容之一。但是大部分指标方法仅具有定性特点且敏感程度受制于背景环境等因素,影响了对湖泊环境演变与水文气候变化过程的深入了解。因此,从结构涌现秩序的理念出发,基于粒度参数指标体系,开发了可用于描述体系结构演化的指标——体系结构量化指数(又称结构异常指数),尝试重建东亚季风边缘区农牧交错带封闭湖泊黄旗海约3 600~1 500 cal a BP年间湖面水位波动。结果显示,在轨道驱动的夏季太阳辐射降低的背景下,黄旗海湖面逐渐降低,期间存在百年尺度的剧烈波动。与基于孢粉重建的山西公海降水量、贵州董哥洞和湖北和尚洞等洞穴石笋氧同位素记录,以及ENSO活跃程度等记录对比分析发现,这种百年尺度的波动与太阳活动驱动的亚洲季风区夏季风降水和ENSO活动密切相关。太阳辐射减弱、夏季风降水减弱、ENSO活动增强,反之亦然。本研究揭示了太阳活动与ENSO、夏季风强度之间的关系,验证了湖泊碎屑沉积结构异常指数能在百年-千年尺度上较好地反演封闭湖泊水位变化。从已有的研究推断,这种反演具有定量属性,这对于内陆湖泊全球变化研究具有重要意义。
