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The ratio of injection–production control area is an important aspect in evaluating the development effect and calculating oilfield development index. Conventional approaches to determine the ratio of injection–production control area neglect the heterogeneity of the reservoir and require long time simulating and a lot of complex iterations. This paper establishes a prediction formula to quickly determine the ratio of injection–production control area in triangle well pattern. A total of 410 sets of streamline models are built to acquire the database. Permeability, oil saturation, injection–production pressure drop and injector–producer spacing are selected as independent variables to establish the prediction formula by multivariate parametric regression. Based on error analysis and application, the accuracy of this prediction formula is approved. Results indicate that the prediction formula has a correlation coefficient R 2 of 0.96, representing a satisfactory performance. Normality and homoscedasticity tests and standardized residual diagnostics demonstrate the statistical significance of the results. The application of this prediction formula shows an excellent match between the predicted and actual injection–production area, which further confirms the accuracy of this prediction formula. The established prediction formula can effectively and accurately decide the ratio of injection–production control area for waterflooding reservoir.

The present study was designed to investigate the antitumor effects of Lactobacillus and the potential mechanisms. Cell Counting Kit-8 (CCK-8) assays were carried out to determine suitable doses for investigating the inhibitory effect of lactobacilli on cell migration ability of HeLa and U14 cells in vitro. In addition, western blot assays were performed to investigate the possible mechanisms corresponding to its antitumor effects. Furthermore, a xenograft mouse model was established for investigating the E-cadherin expression in tumor tissues after treatment with lactobacilli. Our results showed that live lactobacilli [multiplicity of infection (MOI) of 1,000:1] significantly possessed inhibitory effects on cell migration ability of cervical cancer cells. Lactobacilli (MOI: 1,000:1) significantly upregulated E-cadherin expressions in HeLa and U14 cells (p

Vocational skills competition reflects the requirements to the latest vocational skills in various industries and enterprises. As the propeller of the higher vocational education reform and development in the new period, vocational skills competition can promote the teaching reform in higher vocational colleges. The paper discusses the promoting function of vocational skills competition from the perspective of the specialized course teaching, teachers’ level, practice base construction, which will have an important value on the curriculum teaching reform in higher vocational colleges. Reform practice proves that the vocational skills competition plays a great role on the teaching reform in higher vocational colleges. Keywords—vocational skills competition; the teaching reform; higher vocational colleges

The mean and time-varying fluctuation property of local wall shear stress of horizontal air–water bubbly flows in a circular pipe of 35 mm I.D. is measured using a TSI-1268W hot film probe. Data are collected in both entrance and developed regions of the flows. The variation of wall shear stress with L/D is analyzed, and the entrance length is determined to be 52–65 D at present studies. It is found that the wall shear stress is not uniform around the pipe circumference due to the asymmetrical phase distribution in the flows. The mean shear stress tends to decrease circumferentially from the pipe bottom to top. An increase of air flow rate at a constant water flow rate would further lower the wall shear stress at the upper part of the pipe and at the same time raise the wall shear stress at lower part of the pipe in both entrance and developed regions. An increase of water flow rate at a constant air flow rate would result in an increase of wall shear stress at all circumferential positions. The statistical property of wall shear stress is also discussed.

Evolution of BP2T films grown at the early stage was investigated using atomic force microscopy (AFM) and X-ray diffraction (XRD). The AFM results demonstrate that the BP2T grown on the SiO2 substrate transformed from a layer by layer growth to island growth when the coverage is higher than 3 ML. The out-of-plane and in-plane X-ray diffraction measurements reveal a phase transition from the thin film phase to the bulk phase suddenly occurs as the growth mode changes. A careful analysis of the structure evolution implies that not only the strain but also the soft matter property of the organic thin films are responsible for the thickness dependent evolution. Moreover, the thickness dependent structure and phase of BP2T films result in different morphologies of ZnPc grown on different layers of BP2T. The ZnPc crystals gradually changed from stripe-like to nanofiber-like, concomitantly with the epitaxy relationships from incommensurate epitaxy to commensurate epitaxy. Conversely, the diversity of ZnPc films also reflects different properties of the BP2T films with different numbers of layer, which cannot be obtained from the AFM or XRD. This study supplies a deeper insight into the thickness evolution of organic thin films and to the weak epitaxy growth.

Under the conditions of intensive breeding, animal environmental welfare are not guaranteed, which will affect animals' health and the quality of animal products. Therefore, to effectively ensure the quality and safety of animal products, we should improve environmental welfare from microbial aerosols, ground and bedding materials, lighting, ventilation, ammonia consistence, temperature, density, noise etc. In the 1960s to 1970s, People began to pay attention to the animal welfare in intensive breeding , after livestock and poultry husbandry changed from extensive range to intensive animal husbandry.(1) People observe that the conditions of the animal welfare directly affect the productivity. Hence, it's crucial to take some management measures, especially attaching great importance to the research of animal feed, enhancing nutrition such as the improvement the feed industry level, the development of complete feed, and reducing the morbidity and mortality by targeted animal immunization, which realize the aim of enhancing economic efficiency to certain extent.(2) But generally speaking, animals' living environment, quality of life and behavior need are far from satisfied, and animal welfare haven't been improved fundamentally. Under the conditions of intensive livestock and poultry breeding, animal welfare are not guaranteed, which will affect the quality of the animals and animal products.(3) Therefore, in order to effectively ensure the high quality and safety of animal products, it is necessary to take measures to improve animal environmental welfare.