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There are various issues for CO2 flooding and storage in Shengli Oilfield, which are characterized by low light hydrocarbon content of oil and high miscible pressure, strong reservoir heterogeneity and low sweep efficiency, gas channeling and difficult whole-process control. Through laboratory experiments, technical research and field practice, the theory and technology of CO2 high pressure miscible flooding and storage are established. By increasing the formation pressure to 1.2 times the minimum miscible pressure, the miscibility of the medium-heavy components can be improved, the production percentage of oil in small pores can be increased, the displacing front developed evenly, and the swept volume expanded. Rapid high-pressure miscibility is realized through advanced pressure flooding and energy replenishment, and technologies of cascade water-alternating-gas (WAG), injection and production coupling and multistage chemical plugging are used for dynamic control of flow resistance, so as to obtain the optimum of oil recovery and CO2 storage factor. The research results have been applied to the Gao89-Fan142 in carbon capture, utilization and storage (CCUS) demonstration site, where the daily oil production of the block has increased from 254.6 t to 358.2 t, and the recovery degree is expected to increase by 11.6 percentage points in 15 years, providing theoretical and technical support for the large-scale development of CCUS.

In order to analyze and solve the erosion of the inside of nozzle caused by high - speed abrasive particles for improving the nozzle’s erosion and wear resistances and optimizing the structure design of ultra - high pressure jet nozzle, transient two - phase flow simulation, discrete phase simulation and visualization processing were used to simulate the erosion test. An axisymmetric solid - liquid two - phase flow analysis model was established for the inside of the nozzle, and the motion trajectory and acceleration process of the premixed abrasive water jet particles in the nozzle were simulated. Meanwhile, the maximum erosion rate of the nozzle inner wall was calculated, and the internal structure of the nozzle was optimized. Results showed that the garnet abrasive particles collided with the inner wall of the nozzle in the focusing section of the tungsten carbide nozzle and were reflected back to the axis to cause a focusing effect, the particle movement speed decreased and the inner wall was eroded. Furthermore, the maximum erosion rate was 1.9×10-6kg/(m2·s), which arose at the junction between the contraction section and focusing section of the nozzle. The second peak appeared in the middle and front of the focusing section, 20 mm away from the nozzle outlet, and the erosion rate was 1.7×10-6kg/(m2·s). According to the actual test life and failure criterion of nozzle, the calculated actual erosion rate of the nozzle was 1.078×10-6kg/(m2·s) and the correction coefficient of erosion rate was 0.567 4. Generally, the finite element analysis provided a basis for the optimization of the nozzle shape, which was beneficial for the improvement of the corrosion resistance of the nozzle.

BackgroundChronic heart failure (CHF) is a common cardiovascular disease. Improving the self-management ability of CHF patients will contribute to quality of life improvement and reduction of rehospitalization and mortality rates. The Partners in Health (PIH) Scale is a measure designed by Flinders University, Australia, to assess the generic knowledge, attitudes, behaviors, and impacts of self-management in chronic disease patients, and is mainly used to assess the implementation effect of self-management projects in chronic disease patients.ObjectiveTo translate the PIH Scale into Chinese, then test the reliability and validity of the Chinese version in CHF patients, providing CHF patients with a tool for precisely assessing their self-management abilities.MethodsThe PIH was translated into Chinese with the guidance of the Brislin's translation model, then was revised according to the results of the review of a panel of experts, and a pre-test, and then the Chinese version of PIH (C-PIH) was developed. The demographic questionnaire, C-PIH, and Minnesota Living with Heart Failure Questionnaire (MLHFQ) were used in two surveys (one was conducted between April and June 2010, and another between April and June 2011) with 410 CHF patients selected from two grade A tertiary hospitals in Beijing using convenience sampling. Measurement of ceiling and floor effects, and item-total correlation were used for item analysis. Expert evaluation was used to evaluate the content validity analysis. Spearman's rank correlation coefficient was used to measure the criterion-related validity. KMO test, Bartlett's test of sphericity, exploratory factor analysis and confirmatory factor analysis were used for construct validity analysis. Monofactor analysis was used for validity analysis of known-groups. Reliability analysis was estimated by using the Cronbach's α.ResultsItem analysis indicated that only item 3 (level of adhering to medication) of the C-PIH showed ceiling effect. Item-total correlation coefficients of the scale ranged from 0.424 to 0.761 (P