The dynamic interfacial tensions between five types of EOR surfactants and three types of Shengli crude oils were investigated, and the effect of surfactant concentration on interfacial tension was explored. The experimental results show that the different active components in crude oil could react under alkalescent condition and produce the surfaceactive soaps at the interface in situ. The interactions among the added surfactants, active components of crude oil and their products at interface together determined the characteristic behaviors of dynamic interfacial tension. Three types of characteristic dynamic interfacial tension curve might manifest as type "L", type "V" and type "W". The structure and concentration of surfactant and the type of crude oil were key factors impacting on the dynamic interfacial tension characteristics.
Natural ()huperzine A has been found to be an effective inhibitor of acetylcholinesterase (AChE) and can be applied in the treatment of Alzheimer`s disease (AD). The pharmaceutical prospects and lack in natural resource have made the total synthesis of huperzine A an extremely attractive topic in the past decades. In this paper, the progress in the synthesis of the core carbonlectone of huperzine A is reviewed and various types of reactions are summarized in this area.
Copper tungstate was prepared by direct precipitation method at room temperature. The sample was treated with high temperature calcination and activation with hydrogen peroxide in order to improve the oxidative desulfurization activity. Then the oxidative desulfurization of dibenzothiophene (DBT) from model oil was carried out using the activated CuWO4 as catalyst, hydrogen peroxide as the oxidant, and imidazolium fluoroborate ionic liquid as extracting agent．The reaction conditions，including temperature, amount of catalyst and oxidant, types of extractant and sulfides were also studied．The results indicate the optimized desulfurization conditions of 0.4 mL of hydrogen peroxide, 0.02 g of catalyst, imidazole tetrafluoroborate as the extractant at 70 ℃ for 60 min, and the desulfurization rate can reach 93%. In addition, the desulfurization rate remains above 82% when the catalyst was reused for five times.
Corrosion inhibition effect of N(4sulfonic acid) butyl triethylammonium hydrogen sulfate((CH2)4SO3HTEA\]\[HSO4]) acid ionic liquid(IL) towards Q235 steel corrosion in 0.5 mol/L HCl solution was investigated by electrochemical measurements in 25 ℃. The results show that the IL suppressed corrosion processes of Q235 steel in HCl solutionand the best performance of inhibition could be obtained with the concentration of inhibitor 14 mmol/L. The X-ray photoelectron spectroscopy(XPS) demonstrates that the protectiue film is formed by adsorption on the Q235steel surface, which can cover the reative center and inhibit the Q235 steel corrosion in HCl solution.
In this work, the algae rich extract and probiotics ice cream is prepared using the soybean meal extract as the nutrients, and the fermentation liquor that containing the viable bifidobacterium as the additive. The optimal fermentation conditions and the optimal composition of the stabilizers and additives for algae juice are studied. The results indicate the optimal fermentation condition is with the mass fraction of fermentation algae juice is 60%, the mass fraction of bifidobacterium fermentation broth is 5%, fermentation temperature 37 ℃, fermentation time 12 h.The stabilizer of algae juice:the mass fraction of pectin is 0.15%,the mass fraction of propylene glycol alginate is 0.10%,the mass fraction of xanthan gum is 0.10%,the mass fraction of monasodium orthophosphate is 0.05%.The additives of algae juice:the mass fraction of fruit essence is 2%,the mass fraction of bee honey is 6%,the mass fraction of granulated sugar is 6%.This prepared product is a natural health food, which complies with the food healthy standard.
Presently, the constant temperature hot water mixer was produced, because the central hot water engineering was developing towards largescale automation and humanization. The mixer was automatic temperature control equipment, which was the supporting facility of water system. RNG kε turbulence model in CFD software was used, and threedimensional numerical simulation was carried out on the hot and cold water mixer. The flow field and temperature field were analyzed, and the influence of inlet diameter, speed, and temperature on flow field distribution and mixing effect was found out simultaneously. The results could truly reflect the complex flow in the mixer and provide a theoretical basis for studying deeply about the design and improvement of mixer in the future.
Slug flow with varying degrees often occurs in gathering and transportation systems, which makes the flow in the pipelines fluctuate in a certain extent. The fluctuation caused by slug flow made the running of inlet devices in the gathering and transportation system and central treatment station unstable. The flow fluctuation at inlet must be considered when designing inlet devices (usually the primary separator) to inhibit shut down problems due to surpassed flow volume. Suitable design factors were usually considered to relieve the effect caused by flow fluctuation. However, the design factor usually could not solve the unstable problems completely, and dynamic simulation was very necessary. The inlet flow variation, terrain fluctuation and pigging conditions of a gathering and transportation system in a Middle East oilfield were simulated. It was found that the existing separator could guarantee the system operated stable though the inlet flow was fluctuated in a range. The design factor of the inlet primary separator equaled to 1.4 was caused by flow fluctuation.
According to the characteristics that indoor gas leakage is not easy to be diffused in the limited space, the effect of wind speed for the leakage diffusion of indoor gas was analyzed, and indoor gas pipeline leakage model was established. The computational fluid dynamics software was used to make numerical simulation of steady state indoor gas leakage of 2 kinds of gas, natural gas and liquefied petroleum gas. To analyze the volume fraction of the 2 kinds of indoor gas in the space at the wind speed of 1 m/s and 3 m/s, and leakage time of 10, 60, 120 s, and 240 s. The results show that the wind speed could accelerate the diffusion of the indoor gas. The leakage of liquefied petroleum gas was more likely to accumulate, and to form the hazardous area of explosion. The research results could provide theoretical basis for dealing with the gas leakage accident.
In order to ensure pipeline commissioning safety and avoid security risks because of the direct contact between the air and oil, a progress of water isolation was necessary. And how to determine the amount of optimal isolation medium is becoming a new subject. The factors affecting the isolation medium quantity from the point of commissioning process was analyzed and a model to calculate the amount of isolation medium and the mixed oil quantity in a long slope pipeline was built while commissioning, based on existing empirical models, combined with field data. The relative error was in the acceptable range.
In the case of determining the optimum dehydration temperature in the settling tank, the settling tank outlet temperature was obtained by a reverse operation based on the analysis of sedimentation tank of energy balance. One optimal mathematical model, which used fuel oil heating cost and additional insulation layers with different thickness of the total investment cost at least, was established and solved by C++ program. According to the optimized calculation, the optimal insulation thickness was about 68mm and the lowest total cost was about 1.456 3 million yuan.
There is usually difference between gas measuring permeability and liquid measuring permeability, particularly in low permeability reservoirs. Hq, Zb and Hs of the gas permeability and liquid permeability were measured by experiments in the Ordos Basin. The results of experiment show that the lower the permeability was, the bigger the gap between the gas permeability and liquid permeability was. The gap of the oil measuring permeability and gas measuring permeability was obviously different among tight reservoir, superlow permeability reservoir, ultralow permeability reservoir and low permeability. Therefore the result could be used as a demarcation to divide reservoir. The gap of gas permeability and oil permeability had a great relation to the clay mineral, wettability and surface area to the volume ratio.
In the titanium alloy cutting operations with carbide tools, tool wear is one of the main restrictive factors on its tool life, and the cutting temperature significantly affects the tool wear, and closely related to work piece surface integrity and machining precision. Therefore, the analysis of temperature changes of cutting temperature and the tool wear are helpful to increase the productivity and lower down the costs of production. In this paper, the finite element software Deform3D was used to make simulation analysis on cutting temperature field and tool wear during the process of titanium alloy cutting operations with carbide tools. Accoordingly, the influence of the cutting speed, feed and cutting depth, and the dynamic changes of the rake angle of the tool on cutting temperature was achieved, and the change law of tool wear condition with cutting temperature. The findings of this research are helpful to optimize the cutting parameters and research the mechanism of tool wear.
To solve the overlap of part of fault classes in the analog circuit fault diagnostics, a novel analog circuit fault diagnostics approach based on quantum neural networks algorithm was presented. Kurtosis and entropy were calculated as features after the time domain response signals of the circuit under test were measured, and then the different fault classes were identified by quantum neural networks algorithm. The simulation demonstrated that constructed neural network had simple network structure and the fault diagnosis accuracy was higher, which reached 99.62%.
In the production of petrochemical enterprises, the complex distribution of equipment and pipelines could not be remotely controlled by managers. Equipment information could not be associated with spatial location. Various business management systems could not be effectively integrated with the actual production device process. Therefore, according to 3D modeling technology based on virtual reality and webpage technology, petrochemical plant intelligent equipment management information system was designed. Equipment and pipelines' specific shapes were integrated with spatial location, and equipment and pipelines were intelligently managed in the system, truly reflecting the modern enterprise management level.
Starting from the input and output of scientific research in universities, data envelopment analysis (DEA) calculating the relative efficiency of scientific research of universities was used, and the membership function in fuzzy math was used to process DEA results and the evaluation class was determined. By empirically analyzing the research efficiency of 31 domestic universities, the results showed that the scale of the scientific research efficiency of 20 universities was appropriate. And by adjusting the input or output of the other eleven universities, the scientific research efficiency became appropriate. The results of evaluates research efficiency of universities could provide a scientific basis for optimizing scientific research resources.
Using the innovation evaluation theory, a comprehensive evaluation of the technological innovation capability of China's petrochemical enterprises was given. During the evaluation process, the assessment model did not fit the particular type of business, resulting in issues such as inaccurate evaluation results and many subjective factors in the evaluation. According to the views of other scholars, a set of evaluation index system for technological innovation capability of the petrochemical industry was created. By combining AHP and GRAP, a multilevel gray comprehensive evaluation model was established. According to the analysis, the economic indicators of four enterprises were obtained, and these four companies were evaluated by using the assessment model. Finally, according to the evaluation results, suggestions on how to arrange funding of innovative projects and how to enhance the technological innovation capability were provided.
In combination with the characteristics of the unrelated diversification enterprise, it studies the unrelated diversification impact on the cash flow condition.Representative indicators are selected as the independent variables, while the unrelated diversification level as the dependent variable. And then it does the multiple regression model analysis by using SPSS 19. Analysis results show that high level of unrelated diversification will have a negative effect on cash flow situation. On the basis of the quantitative study, enterprises can adopt more effective and targeted measures to reduce financial risk.
