Volume and Surface Distribution Heterogeneity of Nano-pore in Coal Samples by CO2 and N2 Adsorption Experiments

In this paper,the heterogeneity of adsorption pores in middle and high rank coal samples were analyzed by using low temperature N2 and CO2 adsorption technology and fractal theory.The following results were achieved.1)According to the results of volume and surface fractal dimension,meso-pores can be classified into Mep-1,Mep-2,and Mep-3,respectively.Micro-pore can be classified into Mip-1,Mip-2,and Mip-3,respectively.2)Pore types play an important role in affecting the heterogeneity of meso-pores.The volume heterogeneity(VHY)of Mep-1 is simpler than that of Mep-2 and Mep-3 in type A samples.However,the VHY of Mep-1 becomes gradually larger than that of Mep-2 and Mep-3 from type A to type B and C.The VHY of open pore in the same diameter is higher than that of semi-open or closed pore.Meanwhile,the surface heterogeneity(SHY)of types A and B samples is significantly larger than that of type C,the SHY of semi-open or closed pores is more complicated than that of open pores.3)Coal rank mainly affects the heterogeneity of micro-pores.The heterogeneity of type A is always smaller than that of type B and C.The VHY of Mip-1 is more complicated than that of Mip-2 and Mip-3 in the same samples,and the sensitivity of the VHY of Mip-1 and Mip-2 to the degree of coal rank is smaller than that of Mip-3.Meanwhile,the SHY of Mip-1 and Mip-2 is simpler than that of Mip-3 in the same sample,the SHY of micro-pores remains stable as the pore size decreases,and the affect of coalification level on SHY decreases with the decrease in pore diameter.Full-scale fractal characterization has enabled quantitative characterization of adsorption pore properties and provided useful information with regards to the similarity of pore features in different coal reservoirs.

情绪耗竭对建言行为的U型影响--内在动机的调节作用

基于资源保存理论,通过201名员工及其直接上级的配对样本,探讨了中国组织背景下员工情绪耗竭对其促进性建言与抑制性建言的非线性影响及其边界条件。研究结果表明,情绪耗竭对促进性建言与抑制性建言有显著的U型影响。与抑制性建言相比,情绪耗竭对促进型建言的U型影响更明显。内在动机显著调节了情绪耗竭对促进性建言的U型影响,对于低内在动机的员工而言,情绪耗竭对促进性建言的U型影响更明显。

沁水盆地太原组-山西组页岩孔隙分形特征

基于沁水盆地太原组—山西组页岩样品的总有机碳含量、镜质体反射率和矿物组成分析资料,利用高压压汞实验进行测试,获取孔隙直径、孔隙体积、比表面积、孔隙度等孔隙结构参数,并在此基础上利用Sierpinski地毯模型对页岩孔隙结构进行分形处理。结果表明,太原组—山西组页岩样品压汞分形曲线可以分为AB段、BC段和CD段,其中BC段对应的孔隙直径为21~6035 nm;利用Sierpinski地毯模型进行分形处理时,BC段孔隙结构表征性最好;在21~6035 nm孔隙直径范围内,黏土矿物含量越高的页岩,其孔隙结构的非均质性越强,孔隙结构的复杂程度也越高;孔隙体积、比表面积和孔隙度与分形维数均呈负相关关系,三者之中孔隙体积和孔隙度与分形维数相关性较好,可以作为间接判断孔隙结构复杂程度的依据。

MRI定量参数分析肝硬化背景下小肝癌的研究进展

肝细胞肝癌(hepatocellular carcinoma,HCC)是慢性肝炎肝硬化患者的主要死因。其早期症状不典型,检出率低,病死率高,对癌变结节或小肝癌(small hepatocellularcarcinoma,SHCC)早诊早治是提高肝癌疗效最直接和最重要的途径。近年来,磁共振成像(magnetic resonance imaging,MRI)技术发展迅速,包括MRI动态对比增强(dynamic contrast enhanced MRI,DCE-MRI)、体素不相干运动成像(intravoxel incoherent motion imaging,IVIM)、扩散峰度成像(diffusion kurtosis imaging,DKI)、纵向弛豫时间成像(T1 mapping)、LiverLab肝脏脂肪及铁定量等技术,分析肝脏结节癌变的一系列病理生理及血流动力学改变,使小肝癌的检出率显著提高。作者将MRI定量参数分析肝硬化背景下小肝癌的相关研究作一综述。