The geometrical structure of the 1,2,3⁃triazole compounds was optimized by B3LYP/6⁃31G* in density functional theory (DFT), and the obtained structure was confirmed to be the optimal structure by frequency calculation. Based on the optimized configuration, the frontier orbital energy levels and energy gaps of compounds were analyzed. The charge of ADCH in the molecule was calculated, and the theoretical absorption spectra, fluorescence emission wavelengths and IR spectra of these compounds were simulated. Through the analysis of the hydrogen bond interaction with HIV⁃1 protease, it is concluded that this series of derivatives is expected to be used as an imaging anti⁃protein inhibitor. In addition, the reaction mechanism between β⁃lactam carbene and 3,6⁃dipyrazine⁃1,2,4,5⁃tetrazine was studied, and the synthesis mechanism was further clarified, which provided a theoretical basis for the future synthesis of the series of compounds. This provides a theoretical basis for the synthesis of this series of compounds in the future.
The polyvinylidene fluoride (PVDF) as a matrix material was prepared for a bilirubin⁃adsorbed membrane. Firstly, PVDF microfiltration membrane was prepared by vapor⁃induced phase inversion method. The effects of polymer concentration, solvent and additive type on membrane properties and structure were investigated. It is found that PVDF microfiltration membrane has excellent performance and morphology with the PVDF concentration in the casting solution of 7%~8% in quality. When blend solvent of acetone and N, N⁃dimethylformamide and the additive of glycerol were selected, pure water flux is higher than others. Polyethyleneimine was further coated on the matrix to prepare a modified PVDF membrane. The results showed that the modified PVDF membrane had certain serum bilirubin removal ability.
The stability of heavy crude oil emulsion is very important in the heavy crude oil transportation. However, in the pipeline transportation process, the oil⁃water volume ratio, water content (water quality fraction) and other factors have a certain influence on the stability of the heavy crude oil emulsion. The microstructure, stability mechanism of emulsion and the role of focused beam reflection measurement (FBRM) technology in the study of stability of emulsion were introduced. The comprehensive effects of different factors such as oil⁃water ratio, water content and additives on emulsion stability were comprehensively analyzed. Finally, the research status of dynamic stability of emulsions was introduced. The main factors affecting the stability of heavy crude oil emulsions are oil⁃water volume ratio, water content, emulsification temperature and salinity, surfactants, alkaline agents. High molecular polymer used to enhance recovery of heavy crude oil also have effect on the stability of emulsion. The dynamic stability of the emulsion was studied by different simulation methods, and the results were similar. Among them, the loop simulation method had the most reference value
It is the first time to use pot experiment to optimize the pioneer species of Fushun City and apply it to the vegetation restoration in abandoned mines. This article takes the vegetation restoration area of Yushu iron mine and Aoniu iron mine dump in Fushun City, Liaoning province is taken as the research object, based on the pot experiment, combining with the sample characteristics of the soil matrix in the vegetation restoration area of the mine, the effects of different slope positions on the soil fertility of pioneer vegetation were studied. Research indicates:through the pot experiment, in consideration of the survival rate, tree height and the growth and change of the breast diameter of the potted seedlings, the 2 years old of Pinus sylvestris and Locust were determined as pioneer tree species and used to repair the vegetation in the dump of Yushu iron mine and Aoniu iron mine respectively; during the recovery period, the content of soil nutrient content was determined year by year. The content of soil pH, organic matter, total nitrogen, alkali hydrolysable nitrogen, available phosphorus and available potassium increased year by year, and the different slope positions of the plots are characterized by the gradual increase of the slope from the slope to the bottom of the slope.
Aiming at the reservoir characteristics of strong reservoir heterogeneity, circulation way widely distributed and poor water flooding effect in X oilfield of yanchang, a kind of nano⁃microsphere oil displacement agent WQ⁃3 was systhesized. The microstructure, swelling property, viscoelasticity and shear resistance performance were evaluated through the indoor experiments. The core⁃flow experiment was used to evaluate the performance of the regulator in heterogeneous core. The results showed that nano⁃microsphere WQ⁃3 are spherical nanoparticles with good roundness and the average particle size is 404.92 nm. At 80 ℃ in simulated formation water, the expansion ratio of the nano⁃microspheres after 24 h of water absorption is 34.96 g/g. Nano⁃microsphere WQ⁃3 has obvious viscoelastic properties after water absorption, showing the properties of soft solids. At high shear rate, nano⁃sphere WQ⁃3 system has better shear resistance; the injection pressure rises rapidly and the oil recovery increased as high as 14.25% of the injection of WQ⁃3 system.
Double perovskite oxide Sr1.85MgMoO6-δ was synthesized by sol⁃gel method in 5% H2/Ar, and its structural stability was characterized by XRD. The experimental results show that the structure and phase composition of Sr1.85MgMoO6-δ have not changed after high temperature oxidation treatment, which fully proves its structural stability. The conductivity, thermogravimetric and electrochemical impedance spectra of Sr1.85MgMoO6-δ and Sr2MgMoO6-δ were measured in the same environment. The experimental results show that Sr vacancy can effectively enhance the conductivity of the material itself and increase the oxygen vacancy of the material. In addition, the polarization impedance value Sr1.85MgMoO6-δ (2.26~0.56 Ω·cm2) in H2 is smaller than that in Sr2MgMoO6-δ (4.80~1.96 Ω·cm2) at 700~800 oC temperature. Therefore, Sr1.85MgMoO6-δ double perovskite material is a very promising medium temperature solid oxide fuel cell (SOFC) anode material.
The aluminum source is made of Al2(SO4)3 solution, and the precipitant is made of NH4HCO3 solution. By modifying the aging step in the preparation process, the structure of the precursor aluminum ammonium carbonate (AACH) and the calcined γ⁃Al2O3 are modulated, and a high specific surface area nano γ⁃Al2O3 with a hierarchical pore structure was prepared. PtSnK/γ⁃Al2O3 long chain alkane dehydrogenation catalyst was prepared with macro⁃mesostructured hierarchical γ⁃Al2O3 as the carrier. C10―C13 long chain alkanes were used as raw materials to evaluate the activity and stability of the catalyst in a small fixed bed reactor. The results of the study indicated that the γ⁃Al2O3 support obtained after secondary modulation had a macro⁃mesostructured hierarchical pore structure, and the pore size distributions of mesopores and macropores were relatively concentrated. The average pore diameter, pore volume, and specific surface area were 25.40 nm, 2.09 cm3/g, and 284.5 m2/g, respectively. The initial conversion of long⁃chain alkanes dehydrogenation over PtSnK/γ⁃Al2O3 catalyst has reached 26.9% under accelerant condition and after 18 hours can still achieve 21.3%, the dehydrogenation conversion rate is higher than that of commercial alumina.
At present, Bohai L oilfield has entered the adjustment stage of Cr3+ polymer gel flooding ("polymer flooding"). It is urgent to search for further EOR method after polymer flooding. In view of the actual demand of the oil field, the physical simulation research on the method of improving the recovery rate after the polymer flooding and the optimization of the injection parameters are studied in this paper. The result shows that compared with the" high molecular weight " high concentration polymer solution,the salt resistant polymer solution, "polymer/surfactant" two element system and "alkali/surfactant/polymer" three element system, the increase in recovery rate of Cr3+ polymer gel flooding is larger after polymer flooding, and the technical and economic effect is better. with the increase of the size of the slug injected into the plug, the increase of the recovery rate shows a trend of "first increase and then decrease". When the size of the injected plug is 0.2 PV, the ratio of the largest.Under the conditions of the same size of flooding agent slug, compared with the whole slug, the recovery rate of "Cr3+ polymer gel + water + polymer solution + water" or "Cr3+ polymer gel + water" alternate injection increased greatly, showing that the injection mode can slow down the process of "suction profile inversion" and further improve the wave sum coefficient of low and medium permeability layers.
Ignition is the key technology of in⁃situ combustion, which is related to the smooth start of in⁃situ combustion. Because the structure of artificial ignition device was complex, there are some risks of pressure fluctuation and casing damage during operation. Based on the working principle of the traditional igniter, a discardable ignition device for oil reservoir is proposed. The basic structure, installation method and construction process of the igniter are designed. The ignition device provides the necessary heat to start in⁃situ combustion by the solid fuel combustion. It is droppable and no need to recover after complete combustion. The device can avoid construction risk while satisfying the requirements of the ignition. A calculation results of the example shows that the device is feasible and can improve the ignition success rate effectively.
In order to study the erosion and wear of sand⁃bearing crude oil pipeline on elbow, the Euler⁃DPM bidirectional coupling model was established by using CFD analysis software.By changing the inlet flow rate, particle mass flow rate, particle diameter and other conditions, the flow field distribution and simulation were carried out with 45° elbow as the research object. The results show that the maximum wear rate increases exponentially with the increase of inlet jet velocity, and the velocity coefficient is 2;under the conditions of constant inlet flow rate and particle size, the maximum erosion wear rate increases linearly with the increase of discrete phase mass flow rate, and the slope is 1.633; the other variables are constant, the particle size is between 50～350 μm, and the maximum wear rate increases with the particle size. The maximum wear rate kept below 3×10－9 kg/(m2·s).When the particle diameter was larger than 350 μm, the maximum wear rate increased rapidly, and the maximum value was 12×10－9 kg/(m2·s).
In order to study the dynamic process，damage of liquefied natural gas (LNG) leakage and diffusion(LNG), a Gaussian smoked mixture model with point source continuous leakage modified by Gaussian smoke group model was selected and programmed by MATLAB software to study different grounds. Half of the lower limit of the explosion(1/2LFL), the lower limit of explosion (LFL), and the upper limit of the explosion (UFL) corresponding to different factors, and the influence of the factors such as the effective height of the leakage source on the leakage of LNG gas and the analysis. And the experimental models were verified by Burro No. 9,The results show that the range of the danger area decreases with the increase of the surface roughness. With the increase of the effective height of the leakage source, the concentration of the highest point is decreasing and the danger is reduced at the same time. The scope of the area will continue to decrease.Due to the different wind speed, in the early stage of LNG leakage, the greater the danger area, the greater the wind speed. After the state of the gas cloud is stable, the area of the dangerous area decreases with the increase of wind speed.
Based on the analysis of the lithology of the Lower Permian Shanxi Formation and Benxi Formation reservoirs in the Upper Paleozoic of the Yulin gas field. The influence of sea water temperature and seepage flow rate on the hot oil pipeline unsteady heat transfer is analyzed, the results show that: the relatively greater the see water seepage flow rate is; the longer the radius of the thermal effect in the seepage flow direction of soil temperature field around the pipeline, the shorter the radius of thermal effect vertical to the seepage flow direction, and with the flow velocity increases, the average temperature throughout the soil region increased, the time of the soil temperature to stabilize decreased.
Steam turbines are widely used in electric power, petroleum, petrochemical and aviation industries. The rotor system is a key component of the steam turbine. Because the turbine rotor structure is more complex, high working speed and complex temperature environment of the rotor system easily lead to excessive vibration, rubbing, crack, fracture, other serious accidents and even units damage, resulting in loss of personal and economic property. Through the establishment of a dynamic finite element model for the steady⁃state vibration response of the bending moment excitation of the turbine rotor⁃bearing system, calculation of steam turbine rotor bending moment for steady⁃state vibration displacement and stress response curve, analyses the size and location of bending moment on the influence of steam turbine rotor steady⁃state vibration response, providing theoretical basis for design of steam turbine rotor system dynamics.
The expansion dryer is the critical equipment for the finishing unit of rubber plant.It can remove 90% moisture from the rubber melt. Based on FLUENT software, the flow of rubber melt in the runner of expansion dryer was numerically analyzed. Under different production conditions, such as pressure difference between inlet and outlet, screw speed and so on, the flow law of rubber melt in the runner of expansion dryer was analyzed according to the velocity and pressure distribution nephograms, so as to improve the quality of rubber.
With the continuous development of petrochemical industry, the demand for titanium heat exchanger is increasing year by year in China. Unlike other material heat exchangers, titanium heat exchangers have strict requirements of gas protection when welding heat exchanger tubes and pipe plate joints.Inert gas protection should be applied to molten pools and welds and heat affected zones at temperatures over 400 ℃. In actual production, this intended purpose was achieved by adding a protective gas nozzle to the tungsten electrodes and adding a gas shield for the tube plates. In the whole welding process, gas shield of tube sheet needs to be moved the tube plate gas protection cover constantly based on the welding position.The process is cumbersome and the production efficiency is low.In this paper, Having used ANSYS Workbench numerical simulation software to simulate the temperature field of joint’s welding process and improving the traditional gas protection measures based on the distribution of temperature field.After the actual welding test,This improved gas protective measure worked well and could be applied to actual production.
In order to promote the sustainable development of society, the state proposes to build a green financial system to guide social capital to provide financial support for green projects. As an important direct financing tool in the green financial system, the development of green bonds has played an important role in promoting the reform of ecological civilization system. In this context, exploring the factors affecting the coupon interest rate of green bonds will help to reduce the financing costs of relevant subjects. Using empirical analysis methods, the possible factors affecting the green bond coupon rate are selected from the macro, corporate and bond elements. Through the establishment of multiple regression models, market interest rates, domestic inflation, corporate registered capital, return on net assets and credit are finally obtained. The rating has a significant impact on the green bond coupon rate and provides reasonable advice for the continued development of the green bond market.
The research on the relationship between competition strategy and financial performance has always been an important research topic of enterprise management, and the change of environment will affect the relationship. The listed oil companies in China were selected as research samples to study the relationship between the competitive strategy chosen by Chinese oil companies and the comprehensive financial performance of enterprises before and after the "the Belt and Road" strategy. Firstly, the factor score of enterprise competition strategy is calculated by confirmatory factor analysis, then the comprehensive financial performance of enterprise is calculated by grey relational system analysis method, and finally the regression model of competition strategy and financial performance is established. The empirical results show that the competition strategy has a significant impact on the financial performance of enterprises. Before the "the Belt and Road" strategy was put forward, China's oil enterprises mainly focused on low⁃cost strategy, and in the late stage, in order to adapt to the implementation of the "the Belt and Road" policy, China's oil enterprises gradually changed from a single low⁃cost strategy to the use of low⁃cost and differentiation strategy of mixed strategy.
