Research on reservoir bed heterogeneity,interlayers and seal layers and controlling factors of 2+3 sands of upper second member,Shahejie Formation,in the west of the Pucheng Oilfield

Terminal fans have formed the sedimentary system of the 2＋3 sands of the upper second member, Shahejie formation in the west of the Pucheng Oilfield, Bohai Bay Basin, East China. Based on well logging data and physical properties of the reservoir beds, the 2＋3 sands were divided into 16 sublayers. The heterogeneity of reservoir beds and distribution of interlayers and seal layers in the 2＋3 sands were investigated. The intra-layer heterogeneity and inter-layer heterogeneity primarily belong to the severely heterogeneous classification. The spatial differentiation of sedimentary microfacies resulted in a change of reservoir bed heterogeneity, strong in the middle and southern parts, weak in the northern part. Spatial distribution of interlayers and seal layers is dominated by sedimentary microfacies, and they are thick in north-eastern and middle parts, thin in the south-western part.

Calligraphy and Seal Engraving Exhibition at Sinitude Gallery

On April 9, 2010, an exhibition of the calligraphy and sealengraving works of Wang Yuzhong opened at Sinitude Galleryin the Chaoyang District of Beijing. Famous artists

Effects of Sealing Flow Supply Configuration with Holes on Sealing Effectiveness of Turbine Rim Seal

This paper proposes a new-designed rim seal configuration with sealing holes based on the conventional radial rim seal,and presents a numerical comparison of the sealing performance between the conventional sealing flow supply configuration and the new sealing flow supply configuration with holes at different sealing flow rates.The sealing effectiveness and unsteady flow yields at the rim seal are numerically simulated by using the URANS method and SST turbulent model from ANSYS CFX.The influence of the new sealing flow supply configuration on the sealing effectiveness at different sealing flow rates is determined.The effectiveness of different sealing flow rates in the conventional rim seal is also studied.As to the conventional rim seal,the increase in the sealing flow rate reduces the degree of gas ingestion induced by the effect of mainstream ingress at the rim clearance,while the unsteady flow characteristics are enhanced,and the number and amplitude of the low-frequency signals increase.The position of the Kelvin-Helmholtz instabilities vortex structures is left by the increased sealing flow rate,and its strength is suppressed.Compared with the conventional rim seal configuration,the new sealing flow supply configuration with holes could reduce the sealing efficiency by 5.06%at most at sealing flow distribution m_(1):m_(2)=3:1 when Cw=2000,and improve the sealing efficiency by 11.71%at most at sealing flow distribution m_(1):m_(2)=1:1 when Cw=7500.It shows that the lateral jet from the holes induces a larger-scale Kelvin-Helmholtz vortex structure at Cw=2000,thus the sealing efficiency in the wheel space is also reduced.However,the size of the Kelvin-Helmholtz vortex structures is significantly suppressed by the new sealing flow supply configuration at Cw=7500,which is beneficial to improving the sealing effectiveness of the conventional rim seal.

Distribution patterns of typical enzyme activities in tundra soils on the Fildes Peninsula of maritime Antarctica

Soil enzyme activities can be used as indicators of microbial activity and soil fertility. In this paper, the activities of invertase （IA）, phosphatase （PA） and urease （UA） were investigated in tundra soils collected from marine animal colonies, areas of human activity and background areas on Fildes Peninsula, maritime Antarctica. Soil enzyme activities were in the range of 1.0- 82.7 mg·kg^-1.h^-1 for IA, 0.2-8.2 mg·kg^-1.h^-1 for PA and 0.2-39.8 mg·kg^-1.h^-1 for UA. The spatial distribution patterns for soil enzyme activities corresponded strongly with marine animal activity and human activity. Significantly higher soil IA and PA activities occurred in penguin colony soils, whereas seal colony soils showed higher UA activity. Statistical analysis indicated that soil IA activity was controlled by the levels of soil nutrients （TOC, TN and TP）, PA activity was closely related with TP, and UA activity was affected by the soil pH. Overall, the deposition amount of penguin guano or seal excreta could impact the distribution of enzyme activity in Antarctic tundra soils. Multiple stepwise regression models were established between the enzyme activities, soil physicochemical properties and heavy metals Cu and Zn （[IA]=0.7[TP]--0.2[Cu]＋22.3[TN]＋15.1, [PA]=0.3[TP]＋0.03[Mc]＋0.2, [UA]=16.7[pH]-0.5[Cu]＋ 0.4[Zn]-72.6）. These models could be used to predict enzyme activities in the tundra soils, which could be helpful to study the effects of marine animal activity and environmental change on tundra ecosystems in maritime Antarctica.