This paper uses Aspen Plus software to carry out steady?state simulations of a new process for the reactive distillation of hydrogen peroxide isopropylbenzene (CHP) and subsequent refining processes for phenol and acetone. The operating pressure, feed position and number of plates of the reactive distillation column and the refining process were economically optimised with the objective of minimising the total annual cost (CTAC). The results show that the optimal operating parameters of the process are as follows : the total number of trays of RD was 34, the number of trays in the distillation section was 27, the number of trays in the reaction section was 6, the feed position was 28, and the operating pressure was 3.0×104 Pa. The total plate numbers of acetone refining tower (T101), cumene top tower (T102), tar tower (T103) and phenol refining tower (T104) were 25, 61, 23 and 22, respectively. The feed positions are 16, 45, 9 and 9, respectively. The operating pressures were 5.2×104, 5.0×103, 5.5×104, 6.0×103 Pa. The minimum CTAC of the new process was 2 239.03×104 yuan/year. At the same time, the steady?state simulation and economic optimization of the traditional CHP decomposition and subsequent phenol and acetone refining process were also carried out, and the minimum CTAC value was 2 608.13×104 yuan/year. By comparing the reactive distillation process with the traditional process, it can be seen that CTAC can save 14.15% and energy consumption can save 9.01%.
Oily sludge has been classified as hazardous waste because of its complex composition， high stability and difficult treatment. At present， the treatment technologies of oily sludge include landfill， solvent extraction， thermochemical cleaning， ultrasonic assisted treatment and biological treatment. Among them， the thermochemical cleaning technology has the advantages of easy operation and high reliability， and the key technology lies in the selection of cleaning agent. Different types of single cleaning agents are introduced， including inorganic sal cleaning agents， chemical surfactants and biological surfactants. This paper classifies and summarizes the compound of different types of single cleaning agents， and focuses on the mechanism of the compound of non?ion?anionic surfactant， non?ion?non?ionic surfactant， alkaline inorganic salt?surfactant and biological surfactant. Based on this， the development direction of thermochemical cleaning agent is prospected in order to improve the cleaning effect of oily sludge.
Citric acid type deep eutectic solvent was synthesized using citric acid（CA） and choline chloride (ChCl) as raw materials. The existence of hydrogen bonding in deep eutectic solvents (DESs) was determined by infrared spectrum and hydrogen spectra. Sulfide in simulated oil was removed using DESs as extractant and potassium bisulfate as oxidant. The effects of the amount of water, the amount of oxidant, the ratio of hydrogen bond donor and acceptor, reaction temperature and different sulfides on desulfurization rate were investigated, and the optimum reaction conditions were determined. The results showed that the removal rate of DBT in simulated oil was 98.50% at V（model oil）=5 mL, n（ChCl）/n（CA）=1.0∶0.5, V（DES）=2.0 mL, T=30 ℃, m(catalyst)=0.6 g, m(water)=0.4 g. After five times of recycling, the desulfurization rate remains above 95.00%.
The interaction between chiral molecules and plasmons plays a crucial role in regulating the circular dichroism (CD) of chiral modified nanostructures. The direct interaction between chiral molecules and metals can trigger aggregation, thereby affecting their optical properties. In this study, we experimentally synthesized a chiral Core Shell Structure (Au@molecule@SiO2）. Due to the presence of a SiO2 shell layer, the particles retain molecular and metal properties while maintaining good stability. Here the UV?Vis absorption spectra and CD spectra of the chiral?modified structure (Au@molecule@SiO2) were measured, and the CD signal induced by the chiral molecules was found at the plasmon resonance position of Au Nanoparticles (Au NPs) (530 nm). To explore the underlying physical mechanism, Mie theory was used to further reveal that the induced CD signal at 530 nm mainly comes from the interaction between electric and magnetic dipoles in the chiral core?shell structure. This work provides experimental references and an effective theoretical framework for the study of chiral core?shell structures.
A mononuclear Cu complex Cu0.5(4,4'?bipy)(H2O)·L·0.5(4,4'?bipy)·2H2O (1) was obtained by hydrothermal reaction with Cu2+ as the central ion and 4,4'?bipy as the nitrogen?containing auxiliary ligand. Its structure and composition were characterized by modern characterization methods, such as X?ray single crystal diffraction, elemental analysis and infrared spectrum. The results show that Cu2+ is six coordinated with four nitrogen atoms of 4,4'?bipy molecules and two oxygen atoms of H2O molecules, showing a distorted octahedral coordination configuration. L2- anion only balances the positive charges in compound 1 and does not participate in the coordination of metal Cu2+. Cu2+ coordinates with 4,4'?bipy and H2O molecules to form a lattice layered structure [Cu(4,4'?bipy)2(H2O)2]2+, the hydroxyl group of L2- anion and free H2O molecules form hydrogen bonds with H2O molecules in the layered structure respectively, which increases the thermal stability of H2O molecules in compound 1. The fluorescence emission of compound 1 is at 409 nm, which can be attributed to the intraligand emission state. Compared with the ligand, there is a slight red shift, which may be caused by the coordination between 4,4'? bipy ligand and Cu2+.
Taking a heavy oil in Shengli Oil Field as the research object,the core was filled with porous medium in the core displacement instrument to simulate the formation conditions,and the aquathermolysis of heavy oil under different reaction conditions was studied.The results shown that the viscosity reduction rate of heavy oil can reach 20.8% only in porous medium by direct displacement,and the viscosity reduction effect is more obvious in porous medium system after the addition of amphiphilic catalyst for reaction.The displacement viscosity reduction rate after reaction in a low?temperature environment of 65 ℃ is 57.9%.However,the reaction in a low?temperature environment leads to an increase in the molecular weight of the asphaltene component,with the relative molecular weight of the asphaltene increasing from 5 244 g/mol to 6 690 g/mol.After the reaction is completed and maintained in a high?temperature environment of 265 ℃,the displacement has a better viscosity reduction effect,with a maximum comprehensive viscosity reduction rate of 96.0%.It provides an important guiding significance for the optimization of operating conditions of heavy oil aquathermolysis in the field application process.
The Bohai Sea is very rich in heavy oil reserves. At present,the thermal recovery rate is so low that the potential for tapping the potential is huge. It is of great practical significance to discuss the feasibility of gas injection exploitation in offshore heavy oil field. Through gas injection expansion experiments and multiple contact experiments, the effects of different gas injection media (CO2,N2,natural gas) on heavy oils with different viscosities in the Bohai Sea (general I?1, general I?2?A, general I?2?B) the solubilization,expansion,viscosity reduction effect and mixing mechanism.The experimental results show that the compatibility of CO2 and heavy oil is better than natural gas and better than N2, the viscosity reduction rates of CO2 to the three types of heavy oil are 78%,85%,and 90%,respectively,and the viscosity reduction rates of natural gas to the three types of heavy oil are 29%, 69%,and 62%, respectively. CO2 injection is more suitable for general I?2?B heavy oil, and natural gas injection is more suitable for general I?2?A heavy oil; the results of multiple contact experiments show that the mass transfer mechanism of CO2 flooding is dominated by dissolution and condensate, the mass transfer mechanism of N2 flooding is dominated by extraction and extraction, and the mass transfer mechanism of natural gas flooding is the condensate?extraction balance; in addition, the theoretical minimum miscible pressures are all greater than 43.00 MPa, so it is difficult to form miscible at the displacement front. The research results can provide important basis and technical support for gas injection to enhance oil recovery in Bohai heavy oil fields.
In order to determine the reasonable shape of the patching plate for the corrosion defects in the bottom of crude oil storage tank, this paper used finite element analysis to calculate the changes of the stress value in the corrosion defects after repairing different patching plate shapes, and then investigated the stress distribution and the safety factor value of the patching plate, and finally gave the best shape of the patching plate for the bottom of 20 000 m3 crude oil storage tank in Liaohe oil field. The results show that the best shape of the patching plate is a round patching plate. After repairing the corrosion defect, the stress value in the corrosion defect only decreases with the increase of the radius of the patching plate after the repair of the corrosion defect, and does not change with the change of the depth and radius of the defect. With the increase of the radius of the patch plate, the cost and safety of the patch plate will also increase, the specific size of the patch plate should be developed in accordance with the actual situation of the project. The results of the study can give theoretical guidance to the tank bottom repair from a scientific point of view.
The motion output accuracy of the mechanism has been significantly affected by the performance degradation of components. In this paper, the cumulative factor of wear degradation is considered. On the premise of small samples, an analysis method of time?varying reliability of mechanisms is proposed. This analysis method applies the cosimulation of ADAMS and MATLAB. Based on the Archard wear model, the pin radius degradation is calculated and considered as a time series problem. The mechanism function is established according to the RSM method, and the ARIMA method is used to predict the change of the mechanism response value under the subsequent wear cycle to expand the data samples. Based on the interference model of stress?strength,the limit state equation of mechanism is established and the time?varying reliability is calculated. The convenience and accuracy of this method are demonstrated with a crank?slider mechanism.
Titanium alloy TC4 will have problems such as workpiece deformation and bonding during the machining process, so the processing is difficult. This study used ABAQUS software to create a simulation model. In this paper, the influence of ultrasonic elliptical vibration turning and conventional cutting on the mechanical characteristics of titanium alloy TC4 was compared, and the influence of the cutting speed, tangential amplitude, frequency and cutting depth of ultrasonic elliptical vibration turning TC4 titanium alloy on the cutting force was analyzed. The results show that the average cutting force of ultrasonic elliptical vibration cutting increases with the increase of cutting depth and cutting speed, and decreases with the increase of tangential amplitude and vibration frequency. Compared with conventional cutting, ultrasonic elliptical vibration cutting can significantly reduce cutting force, improve surface machining quality and improve machining efficiency..
In this study, a flexible mechanical finger was designed, and the mold of flexible mechanical finger was printed with a 3D printer, and a flexible mechanical finger was made from silica gel. The model parameters C10 and C20 of the strain energy density function of the silicone material were obtained by tensile test, and the three?dimensional model of the flexible mechanical finger was established by Solidworks, and the stress and strain of the flexible mechanical finger were analyzed by ABAQUS software at the pressure of -0.02 MPa to 0.05 MPa.The results showed that the maximum stress and strain values were -8.866 MPa and -0.564 at -0.02 MPa, and 2.981 MPa and 0.711 at 0.05 MPa, respectively. The maximum transverse displacement was 7.60 mm.
Aiming at the problems of traditional neural network in mining transformer time series relationship, poor generalization of classification and low accuracy of classification for heterogeneous data, this paper proposes an improved transformer fault diagnosis model based on bidirectional recurrent neural network. The model extracts features through bidirectional recurrent neural network, fuses the features at the front and back time, classifies the feature data using multi?kernel learning support vector machine method, and fuses the features in multi?kernel learning support vector machine, so as to improve the accuracy of feature data classification. The accuracy and validity of the bidirectional recurrent neural network based on multi?kernel learning support vector machine model are tested through numerical simulation analysis of the temporal channel length for sequential network diagnostic performance, the influence of and multi?kernel learning on the generalization ability of support vector machines, and the influence on heterogeneous data processing capabilities. The experimental results show that the diagnosis performance of the bidirectional recurrent neural network based on multi?kernel learning support vector machine is better, and the prediction accuracy of the model is higher than that of several commonly used neural networks.
The fast braking of resistant load and the falling speed control of the potential energy load are of great significance to improve the operation efficiency and the safety of motor drive equipments. In this paper, a method of constant current braking and dynamic adjustment of falling speed of lifiting objects for DC motor is proposed, in which the conventional energy consumption braking resistor is replaced by a power MOSFET and the equivalent resistance between its leakage and source can be adjusted by voltage control. Under the condition of no need to change the hardware, the double closed?loop control technology of current and speed is adopted to realize the requirements of the whole process constant current fast parking brake, the fast dropping of suspended objects and the falling speed continous adjustment control in the motor drive system. Theoretical analysis and experimental results show that the time for the parking brake and the time for the falling speed of the liftting object to reach stability are reduced respectively to 66.7% and 33.3% of the conventional braking method without chaning changing the hardware system, which effectively improves the dynamic working efficiency of the motor drive system and the flexibility of the control system.
Due to the huge amount of the customers'data the rise of various financial products and the short?term impact of the epidemic, banks are facing with increasing pressure resulting in the business volume declined sharply. The traditional classification tree model can not make more accurate prediction of long?term deposits and carry out accurate marketing to customers according to customer information. Therefore, this paper proposes a three?layer neural network model. Through the experiment, the customer data of grape Island banking institutions are predicted, and compared with the prediction results of a traditional decision tree, random forest model, AdaBoost model and XGBoost model. The experiment shows that compared with the other four models, the neural network model has a better effect of prediction, the model evaluation AUC reaches 0.977 7 and the accuracy reaches 99.06%.
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