Usually solubility parameters are determined at room temperature. Since it is generally believed that temperature has little effect on solubility parameters, not enough attention is paid to the influence of temperature on solubility parameters. Using the data of Funasaka, the solubility parameters of propylene-butene copolymer after grafting from maleic anhydride were calculated at 120°C, and the solubility parameters were compared with the solubility parameters at room temperature. It is found that although the total solubility parameters do not change much, the Hansen sphere radius and association force parameters increase, so the number of soluble solvents increases significantly, so it is believed that the influence of temperature on the solubility parameters is worth noting. The optimization method used also has certain reference value for calculating three-dimensional solubility parameters.

Fatty acids were prepared by hydrolysis of soybean oil using gel-type strong acid styrene cation exchange resin as catalyst. The effects of oil-water ratio, catalyst and emulsifier dosage on the hydrolysis reaction of oil were discussed by univariate analysis. The trend of hydrolysis rate with reaction time was analyzed. Orthogonal experiments were used to investigate the optimal reaction conditions. The optimal reaction conditions were: soybean oil 30 g, water 14 g, ion exchange resin 1.5 g, emulsifier 0.7 g, reaction time 8 h. The hydrolysis rate under these conditions was 72.5%.

Taking the power consumption of the generator as the objective function, the upper and lower limits of the generator power output and the upper and lower limits of the node voltage as the variable inequality constraint, and the nodal power flow equation as the equation constraint to form the mathematical model of the optimal power flow, the nonlinear homotopy internal point method is used to solve the optimal power flow problem. The calculation of IEEE6 and IEEE118 node test systems shows that the calculation results are very close to the results obtained by using the internal point method, and the unfeasible conditions can be detected in time.

By applying the nonlinear PID control theory to the discrete control system of three-phase voltage type active filter, by introducing the nonlinear combination of nonlinear tracking differentiator and PID control signal, the iterative format of the difference equation of the discrete control system based on the three-phase active filter controlled by nonlinear PID control is introduced, and the MAT-LAB simulation of the discrete difference equation of nonlinear PID control and the discrete difference equation of traditional PID control is carried out. The simulation results show that the use of nonlinear PID control can significantly improve the contradiction between the speed and overshoot of traditional PID control, improve the tracking speed of the system, have good robustness, and have good filtering effect.

Using the fuzzy optimization method, multi-objective optimization planning is used to obtain the optimization multi-solution scheme set of power grid planning, and the quantitative objective of the scheme and its eigenvalue matrix are calculated. For the qualitative criteria, an expert system based on planning knowledge and experience is established to obtain the qualitative objective fuzzy evaluation matrix of the scheme. For the two matrices of quantitative and qualitative objectives, the unified decision-making objectives are used to make the scheme optimization decision-making with relative superiority. When the decision-making optimal planning scheme is not satisfied, the weights and their membership functions between multiple objectives are corrected and adjusted, and the optimization planning scheme is recalculated until a satisfactory scheme is obtained. This method can not only consider the quantitative and qualitative factors, but also reflect the overall optimization performance of the system, and apply it to the planning decision support system, which can realize the decision-making function of power grid planning scheme with intelligent simulation.

Using the fuzzy optimization method, multi-objective optimization planning is used to obtain the optimization multi-solution scheme set of power grid planning, and the quantitative objective of the scheme and its eigenvalue matrix are calculated. For the qualitative criteria, an expert system based on planning knowledge and experience is established to obtain the qualitative objective fuzzy evaluation matrix of the scheme. For the two matrices of quantitative and qualitative objectives, the unified decision-making objectives are used to make the scheme optimization decision-making with relative superiority. When the decision-making optimal planning scheme is not satisfied, the weights and their membership functions between multiple objectives are corrected and adjusted, and the optimization planning scheme is recalculated until a satisfactory scheme is obtained. This method can not only consider the quantitative and qualitative factors, but also reflect the overall optimization performance of the system, and apply it to the planning decision support system, which can realize the decision-making function of power grid planning scheme with intelligent simulation.

The nonlinear dynamic bifurcation analysis method and software are applied to analyze the voltage instability caused by saddle junction bifurcation, and the bifurcation analysis is carried out for a typical 3-node power system based on WALVE comprehensive load model. The analysis process shows that subcritical Hopf bifurcation or supercritical Hopf bifurcation may occur when different generator models are used in the same power system. At the same time, two different ways for the system to move towards voltage instability are given: continuous bifurcation through chaos and torus bifurcation due to torus rupture to voltage instability. The evolution process of voltage instability caused by two methods was studied by using the time domain simulation method.

Based on the instantaneous reactive power theoretical detection method of command current signal, a current-based SAPF hysteresis control method is analyzed to analyze the current hysteresis control method of parallel active power filter, which can select the appropriate threshold according to the engineering needs of SAPF compensation effect and the switching frequency limitation of controllable power electronic components. In order to verify the feasibility of this method, MATLAB simulation experiments are carried out. The simulation results show that the current hysteresis control method can reduce the calculation amount and calculation error, improve the reaction speed, and adjust the tracking accuracy according to needs.

Through the test and analysis of a 220 kV substation of Henan Power Grid, it is confirmed that the harmonic current injected into the power grid by the electric traction load on the 110 kV side exceeds the standard, and the 7th and 9th harmonic currents in the capacitor are amplified due to improper configuration of the parameters of the capacitor loop, resulting in frequent burning of the capacitor. By adjusting the parameters of the capacitor loop, the harmonic current amplification is reduced, the harmonic current in the capacitor is reduced, and the normal operation of the capacitor is guaranteed.

Based on the computer algorithm of practical short-circuit calculation of short-circuit current in three-phase short circuit and asymmetric short circuit, as well as the design method of power system graphics program, the calculation of electrical equipment selection is organically combined with the calculation of electrical main wiring and power grid short circuit, and the integrated program of practical short circuit calculation of power system and calculation of electrical equipment selection based on database, expert system and power system graphics is researched and developed. The short-circuit calculation and electrical equipment selection calculation of the program are carried out on the power system graphical interface, and the results are printed out in the form of a report.

The Unified Power Flow Controller (UPFC) is a multivariable controller with multiple control input and output variables, so cross-connection and coupling inevitably exist between multiple control channels formed by these input and output variables. It can be seen from the control theory that the variable pairing selection is closely related to the coupling degree of the multivariable unified power flow control system. The relative gain analysis method in control theory is used to determine the optimal variable pairing relationship for UPFC, and the coupling between UPFC control channels is very weak under this variable pairing control scheme, so that decoupling measures are not required, which simplifies the controller design. The simulation results on the New England system show that under the optimal variable pairing control scheme,

Load control is a traditional means adopted to maintain transient stability when the power grid is disturbed. Emergency load control needs to solve four problems: system power stability, frequency stability, voltage stability, and line load. By comparing with the traditional stability control calculation control method, an emergency load control based on power balance protection is proposed. The implementation principle is: when there is a sudden change in the exchange power between the regional power grids, the power balance requirements after the disturbance are formulated according to the power balance state of the regional power grid before the sudden change, and the load of the system is urgently adjusted after the occurrence of the large disturbance, and the selection and setting method of the emergency load control in terms of time and control points are given.

With the continuous increase of the capacitor current of the system, more and more power grids adopt resonant grounding mode. The resonant grounding method effectively suppresses the re-ignition of single-phase ground fault arc and the occurrence of arc overvoltage, which greatly improves the operation reliability of medium-voltage power grid. An important technical difficulty in the promotion of resonant grounding method is the automatic tracking and measurement of system capacitance current. In order to solve this problem, based on the analysis and comparison of several existing automatic tracking measurement methods, an improved E0 method is proposed.10 kV high-voltage physical simulation experiments show that this method can effectively identify whether the system is in an overcompensated state or undercompensation state, and can correct the value of E0 method online in real time.

In order to optimize the parameters of the power system stabilizer, the parameter design of the power system stabilizer PSS is carried out by using the characteristic root sensitivity under the deterministic operation mode, and the nonlinear programming technology is used to coordinate and optimize the parameters. Then, under the multi-system operation mode, the initial parameters of PSS are designed based on the existing probabilistic sensitivity indicators, and the parameters are optimized by nonlinear programming technology. The trial results on an 8-machine system show that the parameters of PSS can be further coordinated by using nonlinear programming technology.

Anaerobic baffle reactor was used to treat o-nitroaniline wastewater with sucrose as matrix at medium temperature (37°C). The sludge was domesticated by the method of low load and high removal rate, the COD concentration was determined by the standard potassium dacmate method, and the concentration of o-nitroaniline was determined by naphthalene ethylenediamine azo photometry. The results showed that when the concentration of o-nitroaniline in the influent was less than 8 mg/L, the COD concentration was 1200mg/L and the HRT was 1 d, the reactor operated stably, and the removal rate of o-nitroaniline and COD removal rate reached 84% and 85%, respectively.

Some lessons learned from large-scale water diversion projects abroad were introduced, and it was pointed out that it was necessary to conduct ecological environmental impact analysis before implementing large-scale cross-basin water diversion projects. Then, from the perspective of ecological environment, the possible adverse effects of the implementation of the middle route of the South-to-North Water Diversion Project were expounded, and the impact of the project on the capacity and probability of blooms in the middle and lower reaches of the Han River was discussed. Finally, countermeasures and suggestions for maintaining environmental sustainable development are put forward, so as to provide scientific basis for the implementation of the South-to-North Water Diversion Project.

The integration of the structural analysis and design system (CAD/CAE) of the hinged beam, the key component of the six-sided top press of synthetic diamond production equipment, was studied. The mature and universal Pro/Engineer and Ansys were selected as the design system and analysis system respectively, and the two were integrated into an analytical design system of hinged beam through pre-processing and post-processing through IGES data exchange standards. The characteristic parametric modeling of the hinged beam is carried out, the finite element mechanical model is established, and the displacement, strain and stress analysis results of the hinged beam are obtained by Ansys analysis system, which provides reliable analysis data for the structural optimization design of the hinged beam.

The steel bar in concrete is simulated as a beam element that can withstand axial force and resist bending deformation, and under the basic assumption that the displacement of the beam element node obeys the displacement field of the plane element, the model of reinforced concrete plane composite element containing reinforced concrete beam element at any position in the element is established by applying the principle of virtual work. Compared with the existing reinforced concrete planar element model, this model reflects the mechanical properties of the steel bar more accurately and comprehensively, the position of the steel bar in the planar element no longer has any limitation, and the concrete and steel bar can be meshed independently, which provides convenience for the discretization of the unit.

In the pile anchor support structure, the calculation of earth pressure does not consider the displacement of the supporting structure and the unloading rebound of the soil at the bottom of the pit, which can lead to a small calculation value of earth pressure in the active area and a large calculation value of soil pressure in the passive area, which reduces the safety level of the supporting structure. Based on the theory of elastic long pile and classical earth pressure, considering the rebound effect of excavation and the short-term stress history of soil in the construction process, the evolution process and calculation method of soil pressure of pile anchor support structure are studied, and the correlation between the "inverse zero distribution" mode, "zero distribution" mode, "zero distribution" mode, "trapezoidal distribution" mode and "rectangular distribution" mode of earth pressure is proposed, as well as its influencing factors and evolution mechanism. It is pointed out that the calculation of soil pressure of pile anchor support structure should comprehensively consider the influence of excavation speed, exposure time of each working condition and soil rebound characteristics

Based on the analysis of the characteristics of the three types of residential balcony construction area calculation rules since the founding of the People’s Republic of China, the rules that the construction area should be calculated separately according to whether the residential balcony is closed or not are proposed, and the impact mechanism of the rules on the economic benefits and land cost of residential development, as well as the different manifestations in different periods and regions, are clarified. The changes and problems caused by residential design were discussed from four aspects: residential balcony function, indoor physical environment, safety performance and external landscape, and countermeasures and suggestions were put forward to improve the residential balcony area calculation rules, deepen the floor area ratio management regulations, strengthen the review, management and enrichment of design theory of area calculation, so as to guide the scientific and reasonable design of residential balcony.

In order to accurately grasp the change law and influence of steel bar after corrosion, through the experimental research and analysis of 19 corroded steel bars on the outer surface of a power plant-cooling tower wall in Xinxiang, the corrosion mechanism of steel bars and the influence of corrosion on the mechanical properties of steel bars were discussed, and it was concluded that the decrease of the performance of the corroded steel bars was the result of the reduction of the average cross-sectional area of the sample, the stress concentration caused by the existence of the corrosion pit and the change of material, and the change law of the mechanical properties of the steel bar and the corrosion degree of the steel bar were analyzed. The relationship between the weakest section loss rate and the weight loss rate of corroded steel bar is established, and it is used to measure the corrosion degree of steel bar, which provides a basis for the residual bearing capacity, life and durability evaluation of the structure.

Taking the railway horizontal circular oil storage tank (horizontal tank), the main tool in oil transportation, the principle of liquid-solid coupling and the finite element analysis software ANSYS as the tool were used to analyze and calculate the modal mode of the horizontal tank loaded with free liquid at different depths, and the natural frequency of the tank at different liquid depths and the osmogram of the natural frequency of the first four orders were obtained. The analysis results show that the natural frequency value of the horizontal tank gradually decreases with the increase of liquid depth, and the calculation results are quite different when the natural frequency of the system is solved by the coupling method and the average density method.

The non-coordinated displacement mode can effectively improve the calculation accuracy, but the convergence condition is often not satisfied for any irregular mesh. According to the generalized coordination condition under the linear boundary force, a generalized coordination isoparameter is constructed for any irregular quadrilateral element. The derivation of this element takes into account the linear shear stress condition, so that the displacement coordination condition between the elements is satisfied in the sense of weighted residual number. Furthermore, the corresponding generalized coordination should deform function matrix, and the mode is compact and not prone to singularity. Such parameter pairs can pass the sharding test for any irregular quadrilateral mesh, and degenerate into Q6 when the elements are parallelograms. The example shows that the parameter accuracy of this type is high, and the irregular mesh splitting can maintain good numerical behavior.

Genetic algorithm is a global optimization method with extremely robust and wide applicability, genetic algorithm optimization toolbox (GAOT) provides a good tool for the promotion and application of genetic algorithm, it adopts modular design, including commonly used genetic operators. In view of some limitations of traditional PID parameter tuning, the genetic algorithm optimization toolbox is used to tune the PID controller parameters. The application steps of genetic algorithm, the basic usage of GAOT and the interface method of GAOT and controller parameter tuning are analyzed, and the method is compared with the Ziegler-Nichols method and the best engineering quality method by simulation experiments. The simulation results show that the proposed method has almost no overshoot and the shortest transition time, which can significantly improve the system performance.

Using corn gluten powder, a by-product of corn starch production, as raw material, ultrasonic technology is used to extract zeacin from corn gluten powder with different organic solvents. The extraction experiment was optimized by orthogonal test, and the absorbance of the extract solution at 446 nm was measured by ultraviolet spectrophotometry as the assessment index. The results showed that the optimal process conditions were 95% ethanol as the extraction solvent, the extraction temperature was 50°C, the ultrasonic time was 1.5 h, the solid-liquid ratio of zeazanthin to 95% ethanol was 1 g:15 mL, the pH value was 7, and the extraction yield could reach 8.7%.