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When a hypersonic vehicle flies near space, a layer of complex dusty plasma will form around the vehicle under the influence of high temperature, which will cause radar signal attenuation (ATT) to different degrees and lead to communication barriers. Therefore, studying the interaction mechanism between electromagnetic waves and dusty plasma is important. In this paper, the Bhatnagar–Gross–Krook collision model of non-uniform dusty plasma is derived on the basis of Boltzmann's approximate equation. In addition, the modified expression of a dielectric coefficient of weakly ionized dusty plasma is obtained under the condition of magnetization. With the Wentzel–Kramers–Brillouin method, the ATT coefficients of terahertz wave with different external magnetic fields and dusty plasma parameters are calculated. Results show that a strong external magnetic field will cause the ATT of the right-hand circular polarized wave to produce a low absorption band, whereas the ATT of the left-hand circular polarized wave will evidently weaken. The electron concentration, dust concentration, dust particle radius, collision frequency, and charging frequency also influence the ATT under the external magnetic field. These studies provide theoretical references for the research on the blackouts of hypersonic vehicles.

In the process of development in the oilfield, scale has been produced. Thus laboratory-scale deposition tests have been used to understand scale deposition mechanism. The process, mechanism and the main type of the scale in Asp flooding well of the forth plant of the Daqing oilfield were analyzed. To investigate the concentration change of the ions in the formation water with the injection of the Asp complex liquid and the scaling mechanism in the process of Asp flooding the core dissolution test was carried. Some of the scale samples were characterized by scanning electron microscope (SEM), and the results of the element analysis were investigated.

In the process of oil production and processing, there will be produced large amounts of oily sludge, which is one of the important factors that have adverse effects on oil field and surrounding environmental quality. This paper reviewed the current treatment methods of oily sludge, and prospected the future research and development tendency.

Fuzzy system is known to predict model in the electrodialysis process. This paper aimed to study fitting effect by ANFIS in a laboratory scale ED cell. Separation percent of NaCl solution is mainly as a function of concentration, temperature, flow rate and voltage. Besides, ANFIS(Adaptive Neuro-Fuzzy Inference System) based on Sugeno fuzzy model, its structure was similar to neural network and could generate fuzzy rules automatically, using the error back propagation algorithm and least square method to adjust the parameters of fuzzy inference system. We obtained fitted values of separation percent by ANFIS. Separation percent from experiments compared with the fitted values of separation percent. The result is shown that the correlation coefficient is 0.988. Therefore, it is verified as a good performance in the electrodialysis process.

Fuzzy system is known to predict model in the electrodialysis process. This paper aimed to predict separation percent(SP) of NaCl solution as a function of concentration, temperature, flow rate and voltage. Besides, in the MATLAB, ANFIS(Adaptive Neuro-Fuzzy Inference System) based on Sugeno fuzzy model, its structure was similar to neural network and could generate fuzzy rules automatically. We obtained fitted values of SP by ANFIS. Then, we studied these influencing factors on fitted values of SP. Finally, we draw a conclusion that SP is in direct proportion to temperature and voltage, but in inverse proportion to concentration and flow rate.

Oxidation of oily sludge in supercritical water was studied in batch reactor under the conditions of reaction temperature from 390 to 450 °C, pressure up to 25 MPa, and time from 1 to 10 min. The oily sludge oxidation undergoes a parallel-consecutive reaction pathways, in which it first decomposes to intermediates of aliphatic ketones, aldehydes and carboxylic acids with conjugated double bonds and via low molecular mass organic acids to the final product carbon dioxide. A 4-lump kinetic model was proposed to describe supercritical water oxidation of oily sludge. The experimental data obtained were used to estimate the six kinetic constants and the corresponding activation energies in the model. The model testing results revealed that the model predictions were in good agreement with the experimental results. The model helps us get good insight into the performance of the batch reactor that would be useful for optimization of supercritical water oxidation of oily sludge.

In this paper,the different form of polyacrylamide and the production of polyacrylamide at home and abroad are summarized.The history, development and the tendency of polyacrylamide around the world are presented.

Polyaspartic acid (PASP) was prepared by the means of polymerizing maleic anhydride and ammonia solution. In order to find optimal condition of synthesizing PASP, we made a set of experiments on proportion of material, temperature and time of polymerization in the single condition, and compared PASP with other scale inhibitors about the performance of scale inhibition and biodegradation. The results show: the optimal proportion of material is 1:1.1, the temperature of polymerization is 160°C, and the time of polymerization is 1h. Under above condition, we synthetized the PASP its inhibiting efficiency can reach over 95%, and biodegradation rate reaches 70%.

Oily sludge is the solid being discarded or the oily sludge material. Oily sludge mainly comes from human activities in Petroleum Production and sales. In the development and utilization of oil and manufacture of petroleum products, would inevitably product oily waste. In order to achieve thermo chemistry to wash oily sludge and reclaim oil resources from oily sludge, analyzing component of landing oil sludge with Gravimetric Method, the result of analysis is necessary parameter that determine oily sludge cleaning process. The optimal mixing time, washing temperature, liquid/solid mass rate were determined based upon residual oil rate.

During oil production from several wells in Daqing, significant productivity decline was noticed. One of the reasons behind the productivity decline might be scale precipitation. The corrosion is very serious for scaling of the fifth injection wells. It brings enormous damage to oilfield and seriously influences the oilfield production and development. Based on the research of scaling of three different sections of injection wells, we clear the distribution of injection wells scaled and the source of injection water. Choose the representative scaling wells of three blocks and injection water sample, use modern instrument analysis method to analysis the composition of water and scale sample. According to the data analysis, to certain the components of the sample scale, put forward the main form of scaling mechanism, and provide a dependable basis for making effective measures of scale removal and prevention.

By a membrane bioreactor with a settle tank in long-term operation and batch experiments, the effects of flocs, soluble microorganism products (SMPs) and metal ions in activated sludge liquor on membrane fouling were investigated. The results showed that foulants absorbed each other and formed a fouling layer as a "second membrane" influencing the permeability of the membrane. The "gel layer" caused by SMPs and "cake layer" by flocs showed great differences in morphology by analysis of scanning electron microscope and atomic force microscope. The "gel layer" was more compact and of poor permeability. When the membrane flux was 40 L/(m(2) x h), the rate of membrane fouling caused by supernatant (0.011 MPa/h) was greater than that by sludge liquor (0.0063 MPa/h). SMPs played very important roles on membrane fouling. In the bulking sludge, with SMPs increasing, the rate of membrane fouling (0.0132 MPa/h) was faster. While after flocculation of the SMPs, the rate of fouling decreased to 0.0034 MPa/h. Flocs could keep holes in their overlaps. They could alleviate membrane fouling by preventing the SMPs directly attaching on membrane surface.

To investigate the microbial communities of microorganisms cultivated under different carbon sources, three sequencing batch reactors were operated. They were supplied with sewage, glucose and sodium acetate as carbon sources respectively and showed high phosphorus removal performance. The results of denaturing gradient gel electrophoresis (DGGE) of polymerase chain reaction-amplified (PCR) 16S rDNA fragments demonstrated that beta-protebacteria, Actinomyces sp. and gamma-protebacteria only exited in 1 # reactor. The microbiological diversity of 1 # reactor exceeded the other two reactors. Flavobacterium, Bacillales, Actinomyces, Actinobacteridae and uncultured bacteria (AF527584, AF502204, AY592749, AB076862, AJ619051, AF495454 and AY133070) could be detected in the biological phosphorus removal reactors.