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The compression type soluble rubber cylinder used for the conventional dissolvable bridge plug has some problems, such as not easy to dissolve, small applicable temperature window and insufficient strength. Therefore, a new type of water-soluble rubber cylinder synthesized from thermosetting polyester polyurethane copolymer is developed. According to the different material formula, it can be divided into slow soluble type and quick soluble type. The performance of the two water-soluble rubber cylinders is tested by indoor pressure and dissolution experiments. The results of indoor experiments show that the pressure resistance of the two water-soluble rubber cylinders can reach 70 MPa within 24 h after being immersed in 120 ℃ diesel oil environment. In the solution with 90 ℃ constant temperature and 1% KCl mass fraction, the slow soluble rubber cylinders are completely degraded into fragile small pieces within 18 days, during which the quality of the rubber cylinders decreases by 32%, the initial hardness decreases slowly, and the pH value of the solution rises rapidly from neutral 7 after 12 days It was alkaline 13.8, then gradually reduced to 3; the instant rubber cylinder was completely degraded into fragile small pieces in 5 days, during the degradation process, the rubber cylinder mass decreased by 38%, the hardness initially decreased slowly, and decreased rapidly after 1.5 days, the pH value of solution rose rapidly from neutral 7 to alkaline 12, then gradually decreased to 3. The test results can provide technical reference for the field application of two kinds of water-soluble rubber cylinders.

Daqing placanticline has entered a period of ultra-high water cut development, a large number of produced water ineffective circulation, resulting in a significant increase in the investment and operation costs of lifting, gathering and processing links. Reducing the cost of comprehensive development has become a key problem which is restricting the sustainable economic development of high water cut oilfields. In order to solve this problem, the downhole injection-production test of oil-water separation in the same well was carried out. The hydrocyclone was used as the core separation component to separate oil-water two-phase in the tube of production wells, and the high oil-bearing liquid was lifted to the surface and the high water-cut liquid was reinjected to the injection water layer. According to different injection pressure and flow volume, two downhole tubes is researching to suitable for different well conditions: screw pump production - screw pump injection technology tubing string, screw pump production - electric pump injection technology tubing string. 16 wells are experimenting in this process, the average daily production liquid decreased three-quarter, average daily reinjection sewage volume was 60 m3 almost, the water-oil ratio decreased obviously in the surface. The max repair-free period of the test wells was 600 days. The technology greatly reduces the surface sewage treatment volume and the replacement water reinjection volume. The downhole oil-water separation and injection-production technology in the same well realizes “dual-function and injection-production in the same well”, shortening the water cycle treatment process, prolongs the economic recovery period of the oilfield, changing the traditional oilfield production mode. It is one of great significance to reduce the surface input-cost and sewage treatment volume, improving the economic ultimate recovery rate, and has great application value in commerce.

Introduction The development of ideal vaccine adjuvants for intranasal vaccination can provide convenience for many vaccinations. As an ideal intranasal vaccine adjuvant, it should have the properties of assisting soluble antigens to pass the mucosal barrier and potentiating both systemic and mucosal immunity via nasal administration. Methods By using the advantages of polysaccharides, which can promote both T-helper 1 and 2 responses, curdlan sulfate (CS)–O-(2-hydroxyl)propyl-3-trimethyl ammonium chitosan chloride (O-HTCC) nanoparticles were prepared by interacting CS with O-HTCC, and the adjuvancy of the nanoparticles was investigated. Results The results showed that the polysaccharide-based nanoparticles induced the proliferation and activation of antigen-presenting cells. High protein-loading efficiency was obtained by testing with the model antigen ovalbumin (Ova), and the Ova adsorbed onto the cationic CS/O-HTCC complexes was taken up easily by the epithelium. To evaluate the capacity of the Ova/CS/O-HTCC nanoparticles for immune enhancement in vivo, we collected and analyzed immunocytes, serum, and mucosal lavage fluid from intranasally vaccinated mice. The results showed that Ova/CS/O-HTCC nanoparticles induced activation and maturation of antigen-presenting cells and provoked the proliferation and differentiation of lymphocytes more significantly compared to the immunization of Ova mixed with aluminum hydroxide gel. Furthermore, CS/O-HTCC evoked a significantly higher level of Ova-specific antibodies. Conclusion Therefore, these results suggest that CS/O-HTCC nanoparticles are ideal vaccine adjuvants for soluble antigens used in intranasal or mucosal vaccination.

To improve the limitations of information entropy in the power quality evaluation process, a fuzzy comprehensive evaluation method was proposed on Modified Entropy Weights and Catastrophe Verification. Through summing up the six indexes of power quality, and establishing the evaluation level boundary, the positive and negative entropy weights were reckoned for the power quality monitoring units; The fuzzy features and evaluation was improved to be depicted for power quality with Exponent method, and the five level membership function was set for the power quality evaluation; Then, the mechanism was set up for the fuzzy comprehensive evaluation operation. Finally, with the modified entropy information combination mode and the fuzzy catastrophe mode, the fuzzy comprehensive evaluation and comparative analysis was carried on for such power quality. Case showed, the power quality evaluation conclusion of Information catastrophe mode has the good consistency with the weight combination mode of the positive and negative entropy, which could realize the distinction and system evaluation to the different monitoring units.

The fundamental problem of the emergency repair and construction is to evaluate the efficiency of the support plan of emergency supply for earthquake repair. This paper constructs reasonable evaluation model of each support plans' input and output based on DEA and gets the relative efficiency of each support plans to choose the rational plan. When fuzzy DEA can not evaluate the efficiency of support plans in the special case which is after the earthquake and the outputs are fuzzy data, it can get average efficiency by using Monte-Carlo method to simulate the outputs of each support plan and provide decision makers with scientific basis for choosing the rational support plan.

The growth, migration and spread of malignant tumors requires a large number of new blood vessels to supply nutrients. In our previous study, it was found that the hyaluronic acid (HA) modified novel antiangiogenic peptide ES2-AF has better solubility, longer half-life, stronger targeting than non-modified ES2-AF, and it significantly inhibited the formation of new blood vessels. In the current work, we studied the stability of ES2-AF after HA modification, including heat stability, longterm stability, and pH stability. After treatment with HA-ES2-AF, cell apoptosis and the cell cycle were analyzed using flow cytometry. The inhibitory effect of HA-ES2-AF on tumors was investigated in vivo in HepG2 tumor-bearing nude mice. All the above results showed that HA-ES2-AF significantly improved stability, effectively induced apoptosis of endothelial cells, caused G1 phase arrest of endothelial cells, and decreased the percentage of cells in G2 and S phases. In vivo, HA-ES2-AF exhibited an inhibitory effect on tumors growth. In addition, the results provide a reliable basis for studying the inhibition of neovascularization and anti-tumor drugs in the future.

The new unlimited multistage ball-activated fracturing system is researched which is composed of packers and ball seat ports. All ball-operated ports in one single trip can be opened by pumping single size balls. So, the inner diameter (ID) of the fracturing system is large and can support aggressive treatments with high-rate and high-sand-concentration slurries that optimize well simulations and maximize production. In this fracturing system, every ball-activated port is connected with every packer. The diameter of ball seats can be changed by hydraulic pressure. While the initial stage is treated, the tubing–casing annulus pressure is higher than the secondary stage. The high pressure is conducted to the secondary ball-activated port by the bridge channel and makes the diameter size of ball seat reduce. In the same way while one zone is treated, the diameter of ball seat for the next zone is changed. Using single size ball, it can open all ball-activated ports in one single trip. This new fracturing system can be applied for cased wells, both horizontal and vertical wells, using bridge channels to conduct pressure. Especially for refracturing wells, this new system can treat more stages and increase production.

Aiming at the poor applicability, high unproductive energy consumption and the serious wear of the sucker and tube during the application of oil pumping units, screw pumps and electric submersible pumps in low-production and low-permeability wells, directional wells and exceptional wells, a new reciprocating direct-drive electric submersible plunger pump has been developed. For reciprocating direct-drive electric submersible plunger-pump lifting technology, the rotor of submersible linear motor is connected with the plunger of oil-well pump; cable is applied to supply electric energy for the downhole submersible linear motor; and the rotor of motor directly drives the plunger pump to reciprocate and finally realizes the lifting of the produced liquid. For this new-type lifting technology, downhole direct-drive rodless lifting mode is applied, which successfully prevents the wear of the sucker and tube and avoids the unproductive energy consumption that is caused by the movement of sucker rod string when oil pumping units, screw pumps and other rod lifting methods are adopted. Compared to the oil pumping unit with the same displacement, the application of the reciprocating direct-drive electric submersible plunger pump can reduce electric power consumption by more than 40%. Moreover, this new-style reciprocating direct-drive electric submersible plunger pump has no surface movable component, and the well head is sealed. Therefore, it is safe, environmental friendly and easy to maintain.