Research on water quality characteristics in the process of dewatering test for Ordovician limestone aquifer

AbstractNantun coalmine lies in the south of Yanzhou Coalfield which locates in Jining city, Shandong province, China. In order to correctly understand hydrogeological characteristics of Ordovician limestone aquifer, utilize boreholes in roadway to put on large discharge and large drawdown blow down dewatering test. In the dewatering test, regularly collection water sample of Ordovician limestone aquifer and testing hydrochemistry parameters. Research results show that, the hydrochemistry type of Ordovician karst water are single, displaying typical karst water quality feature, and also show that the condition of Ordovician karst's water cycle alternative is poor. On the whole the water quality changes of Ordovician limestone are small, mainly because of in the middle-shallow and deep of Ordovician karst water are interblended in the outlet. During the entire dewatering process the water quality of Ordovician limestone and the upper NO.14 limestone are greater difference. These show the poor relation of the two limestones, the rocks between the NO.14 limestone and Ordovician limestone has better water resistance and safety mining of lower group coal

BMPR2 mutation is a potential predisposing genetic risk factor for congenital heart disease associated pulmonary vascular disease.

Pulmonary arterial hypertension (PAH) frequently arises in patients with congenital heart disease (CHD) and can lead to pulmonary vascular disease (PVD). The present study was initiated to distinguish the predisposing effect of bone morphogenetic protein receptor 2 (BMPR2) in CHD by comparing the different mutation features of BMPR2 between CHD patients with or without PVD. 294 CHD-PVD and 161 CHD without PVD patients were enrolled. PAH was diagnosed by heart catheterization at rest after CHD was first recognized by echocardiography. PVD was defined as a pulmonary vascular resistance (PVR) more than 3 Wood units. BMPR2 gene was screened by direct sequencing. A total of 24 mutations were identified, accounting for 22 of the 294 patients with CHD-PVD (7.5%) and 2 of the 161 CHD patients without PVD (1.2%, P=0.004). Female/male CHD-PVD patient ratio was 1.6:1, while in the BMPR2 mutation carriers female patients were more dominant (4.5:1, P=0.042). A significant higher BMPR2 mutation rate (12.6%) was found in repaired CHD-PVD (P=0.010). BMPR2 mutations in CHD-PVD patients were identified in different clinical phenotypes. Missense mutation of BMPR2 is the dominant mutation type. Genetic predisposing factor may be an important component in the process of development of PVD in CHD patients. Female, repaired patients are more likely to be detected with genetic mutations

Dynamic monitoring research on displacement of rock mass in coal seam floor on the 1604 workface in NanTun coalmine, Shandong Province, China

AbstractIn order to understand the displacement regular of rock mass in coal seam floor, displacement monitoring sensors were arranged in underground boreholes and realized the dynamic monitoring displacement of rock mass. First, the geological and the hydrogeological condition of the 1604 workface and NanTun coalmine were analyzed. Second, boreholes was constructed in roadway on the 1604 workface, displacement monitoring sensors were arranged in boreholes in different depth, when the distance of mining position and borehole was 110 m, the displacement monitoring sensor started monitoring, which the different depth displacement data were collected. Last, through comparing displacement data in different depth, the paper point out as the development of mining the influence degree of the displacement of rock mass in coal seam floor can be divided into initial influence stage, obvious influence stage and significant influence stage. Workface mining caused the depth of the rock mass displacement variation from 11.95 to 13.94 m below coal seam. The result will guide the coalmine prevention and control of water inrush from coal seam floor