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The outstanding problems of water injection wells in an oilfield in Bohai are high injection pressure and shorter validity acidification. Combining the geologic feature of reservoir and the waterflooding development history, the subjects were systematically studied, such as the compatibility of mixed fresh water and polymer-contained sewage, the components of suspended matters, the micro-structures and molecular size of HPAM, the compatibility of injection water and cores, etc. Researches show that suspended solids jam is the main damage forms. Suspended matters are main the flocculation products of the produced polymer with the wastewater treating agents and Ca2+, Mg2+ bivalent cationic, etc. Secondly, they also contain the precipitation of formation fines and produced polymer. Meanwhile, the suspended matters include a few precipitation of CaCO³ and Fe-CO3. In the early time, serious water sensitivity happened caused by fresh water injection. Rigid granules like CaCO3 and FeCO3, the precipitation of mixed fresh and produced water for reservoir flooding, intensified the obstruction level of formation in wellbore area nearby, the flocculating-deposition of produced polymer and other products blocked the deep area of formation, which were the main reasons for the poor waterflood effect and less effective acidification. [ABSTRACT FROM AUTHOR]

Introduction: Red blood cell distribution width (RDW), a measure of heterogeneity in the size of circulating red blood cells, is predictive of adverse outcomes in a variety of diseases. We assessed the prognostic value of RDW in patients with atherosclerotic cardiovascular disease (ASCVD). Methods: We studied 7,849 patients (69±11 years, 65% male) referred to the noninvasive vascular laboratories at Mayo Clinic from January 2005 to March 2013 with follow up through March 2018. Baseline RDW, comorbidities, and mortality were obtained from the electronic health record (EHR). ASCVD phenotypes, namely, abdominal aortic aneurysm (AAA), cerebrovascular disease (CVD), coronary heart disease (CHD), and peripheral artery disease (PAD), were ascertained by validated electronic phenotyping algorithms that included ICD-9-CM and CPT codes, lab values, and medications. Extended multivariable Cox regression models that included a time-dependent coefficient were used to examine changes in the association between RDW and mortality over time. Results: The median RDW was 13.5 (1.3)%, and was highest in PAD patients 13.7 (1.6)%. During the mean follow up of 7.7 years, 1,900 patients (24.2%) died (Table). In Cox models stratified by ASCVD subtypes, with adjustment for age, sex and comorbidities, RDW was independently associated with mortality in all four ASCVD phenotypes. For a unit increase in RDW, impact on mortality was greatest within the first 3 years following the baseline measurement (p-value; AAA 0.02, PAD, CVD, and CHD <0.001), attenuated thereafter and was not significant beyond 5 years (Table). Conclusions: RDW is an independent predictor of near-term mortality across the spectrum of ASCVD and may be useful for prognostication. [ABSTRACT FROM AUTHOR]