Phosphate is an important multifunctional crystal material with broad application prospects in catalysis, photoluminescence, gas storage and separation. In recent years, many phosphate compounds and their derivatives have been used in the study of proton conducting materials. In this paper, the mechanism of proton conduction is briefly introduced. From the operating temperature, the phosphate is divided into two categories with 100 ℃ as the demarcation point. The research progress of phosphate as proton conducting material is introduced, and the challenges faced by phosphate as proton conduction material are prospected.
The epoxidized soybean oil methyl ester was prepared by a non⁃solvent method under a mild condition using molybdenum polyoxometalates as catalysts.The epoxy soybean oil methyl ester with an acid value of 0.58 mg (KOH)/g and an epoxy value of 3.73% could be obtained using a H2O2:C=C of substrate molar ratio of 1.5 with adding 1.5% catalyst [(C2H5)4N]4Mo8O26 when 20 g soybean oil methyl ester was epoxidized at 55 ℃ for 5.0 h. The method has the advantages that the catalyst is easy to be separated and the post⁃treatment is simple. Moreover, the product does not contain inorganic acid, which avoids the influence of inorganic acid on the analysis and treatment of product.
The composite material Hβ/OMC containing the mesoporous carbon (OMC) and Hβ zeolite was synthesized. This composite was characterized with XRD, BET, FITR, SEM and TEM. The adsorption desulfurization performance of Hβ/OMC was investigated with benzothiophene (BT) as the probe molecule. The adsorption thermodynamics and kinetics of the BT on Hβ/OMC were studied. The characterization results showed that Hβ/OMC has the micro⁃mesoporous hierarchical pore structure, its specific surface area, pore volume and pore diameter are all higher than those of OMC. The saturated sulfur capacity of BT on Hβ/OMC is higher than OMC. Compared with Freundlich adsorption isotherm model, the adsorption of BT on Hβ/OMC is more consistent with Langmuir model. The adsorption of BT on Hβ/OMC is a process of spontaneous, exothermic and degree of confusion reduction, which is described better by pseudo⁃two⁃kinetic equations than pseudo⁃one⁃kinetic equations.
Spherical Fe3O4@SiO2 nanoparticles with good dispersibility (denoted as S1) were prepared by Stöber hydrolysis⁃polycondensation method, and the particle size was 300～430 nm.In order to investigate effect of carbon number in the organosilicone on 51 hydrophobicity and demusification of magnetic nanoparticles, the methyl triethoxysilane, n⁃hexyltriethoxysilane, n⁃dodecyltrimethoxysilane and n⁃octadecyltriethoxysilane were used to modify the surface of the S1 respectively, and the products were marked for S2—S5. The magnetic samples were characterized by electron microscopy (TEM), scanning electron microscope (SEM), X⁃ray diffraction (XRD), fourier transform infrared (FTIR) spectra and thermogravimetric analyses (TGA). The static water contact angle of magnetic nanoparticles (θW) were 10.6º、42.6º、113.6º、128.0º and 148.3º for S1—S5 respectively, and the results indicated that the θW increased with carbon number in the silane coupling agent increasing. Besides, the hydrophobic coating amount on the S1 surface of S2—S5 were estimated to be 0.005, 0.087, 0.092 g/g and 0.087 g/g respectively. The samples can be applied to removal the oil from water surfaces. Four kinds of silicone⁃modified magnetic particles can remove the surface oil, the n⁃dodecyltrimethoxysilane modified magnetic particles have the best effect of removing oil.
With the rapid development of economy and the increasingly stringent emission standards, the removal of dust has been a research hotspot. A new type of grounding atomization corona discharge precipitator is designed. During the discharge process, the liquid on the surface of the wire electrode is atomized while the particles are charged, so as to effectively remove the dust. During the experiment, the velocity of air flow is set to 1 m/s and 3 m/s, the flow rate and direction of air flow are changed, and the V⁃A characteristics of atomized negative corona discharge are studied. Secondly, the influence of gas velocity on dust removal efficiency in grounding atomization corona discharge precipitator with 25 mL/min flow rate of the liquid covered on the surface of the wire electrode is studied. Finally, in order to study the dust removal ability for high specific resistance dust by grounding electrode atomization corona discharge technology, cement dust with specific resistance of 1.2×1012 Ω·m is used as high specific resistance dust in reverse gas flow with gas velocity of 1 m/s. The results show that the dust removal efficiency decreases with the increase of gas velocity. The discharge current with the reverse gas flow is larger than that of the forward gas flow when the gas velocity is increased. When the flow rate of the liquid covered on the surface of the wire electrode is 25 mL/min, the current of the negative grounding atomization corona discharge is the largest.The optimum reaction conditions of the grounding atomization corona discharge precipitator are as follows: the flow rate of the liquid covered on the surface of the wire electrode is 25 mL/min when the reverse gas flow rate is 1 m/s. Compared with the traditional dry corona discharge reactor, the grounding atomization corona discharge precipitator has higher dust removal efficiency for high specific resistance dust.
Melting characteristics of MSW incineration fly ash was analyzed by high temperature tubular furnace in the paper, including the material migration of fly ash at high temperature and the leaching analysis of molten glass. The results show that with the increase of reaction temperature, the molten slag produced by fly ash melting decreases relative to the original fly ash, and the volatile matter of fly ash increases at high temperature. The density of the melt vitreum is 5 times more than the stacking density of fly ash, which has good volume reduction effect. The content of chloride ion in fly ash slag became less, most chlorine elements volatilized into gas phase and secondary fly ash. The influence of the Cl- entering gas on the corrosion caused by the melting system will be a process problem to be solved in the future.
With the development of science and technology, the automation and intellectualization of killing technology has become an important direction for the development of oil and gas well control technology. In view of the low efficiency, insufficient safety and imperfect automation of displacement killing, this paper presents a design scheme of automatic displacement killing based on the basic principle and parameter calculation model of displacement killing, and makes sensitivity analysis of the important parameters affecting the killing design. The accuracy of real⁃time monitoring and parameter calculation of automatic killing system directly affects the rationality of killing design. While improving the accuracy of model calculation, we need to configure high⁃accuracy killing monitoring equipment. This scheme can provide some research basis for related researchers and provide some theoretical support for field construction.
The vertical and horizontal heterogeneity of the reservoir in Bohai Q oilfield is strong, so it is difficult to accurately establish the geological model, and there is a problem of low fitting accuracy in the history of reservoir numerical simulation in ultra⁃high water cut period. Based on the theory of percolation mechanics, production logging data and streamline simulation are combined. The combination of the pipe method and the use of production log data to provide the amount of liquid production and water content and stratified injection amount to determine the residual oil saturation and its distribution at any point in the reservoir. By using this method, the measures of flow field regulation of water injection unit and water blockage of local well group are proposed. The output of oil wells is increased by 14 times, and the annual oil production of oilfield is negatively decreasing. The practice shows that the combination of production logging data and streamline simulation can effectively identify the remaining oil distribution, and provide scientific theoretical basis for the development and adjustment of highly heterogeneous reservoirs in ultra⁃high water cut stage.
In order to study the interaction of flowing hydrodynamic force, buoyancy, pipe body, gravity of conveying medium and resistance of soil foundation on pipeline, the mechanical analysis model of pipeline under flood was established. The stress and strain of pipeline were calculated by numerical analysis method and finite element method. The results show that the calculation results of the two methods are close. Based on the finite element model, the effects of flood velocity and crossing distance on pipeline stress and strain are analyzed. The results show that when the velocity is greater than 3.0 m/s, the stress and strain of the pipeline increase with the increase of the velocity. When the crossing distance increases, the maximum stress and axial strain of the pipeline at the embankment gradually increase, but the increase decreases.When the crossing distance is less than 160 m, the stress and axial strain of the pipeline in the middle of the river increase with the increase of the crossing distance, and when the crossing distance is more than 160 m, the stress and axial strain decrease slightly with the increase of the crossing distance. The safety assessment of the buried suspended pipeline of Yulin⁃Jinan Railway is carried out. The results show that the immediate stress is 178 MPa, and the suspended pipeline is safe.
The intensification of the greenhouse effect has led to a gradual increase in people's awareness of carbon capture. Aiming at the carbon capture problem, combining the CO2 supercritical Rankine cycle with the organic Rankine cycle, the original gas turbine exhaust gas power generation system was improved,an LNG cold energy cascade utilization system combining exhaust gas power generation and CO2 capture was proposed. The thermodynamic simulation of the system was carried out using Aspen Plus software, the effects of evaporation pressure and evaporation temperature on the thermodynamic performance of the system were analyzed in detail. The results show that the increasing of the evaporation pressure and evaporation temperature of the CO2 supercritical Rankine cycle have a positive effect on the net output power and thermal efficiency of the system. After the evaporation temperature of the organic Rankine cycle reaches 250 ℃, the waste heat recovery rate reaches the maximum value and no longer changes with evaporation pressure. The net output power of the system can reach 251.6 kW, the recovery rate of waste heat is 92.00% and the exergy efficiency is 57.00%.The amount of CO2 liquefaction can reach 883.6 kg/h, which is equivalent to reducing CO2 emissions by 7.63 million tons per year, and is of great significance to environmental protection.
In order to study the reliability of phased array ultrasonic testing for pressure pipe girth welds. In this paper, φ273 mm×13 mm and No. 20th steel pipe are selected and welded by butt ring welding, The weld area is evenly divided into 6 the same length areas and preburied five different defects. Phased array equipment, X⁃ray equipment and diffraction time difference ultrasonic testing equipment were used to detect the weld seam respectively. The relative data of each defect are measured by phased array equipment, and compared with the data of defect length and x⁃axis location obtained by X⁃ray detection, and with the data of defect height measured by Diffraction Time⁃difference Ultrasound Detection. High reliability of PAUT technology for welding Joint inspection of pressure pipeline. For rework and defect recording, PAUT technology is superior to TOFD ultrasonic detection technology and RT technology.
Stream limiter is an important component of the steam generator in nuclear power plant, which plays a necessary role to ensure the safe operation of the reactor. Based on the CFD numerical simulation method, the flow field characteristics and key performance of two mainstream venturi steam restrictors are compared.The results show that the flow limiting capacity of the nineteen⁃nozzles is 6% higher than that of the seven⁃nozzles,and the pressure loss is only 67.3% of that of the seven⁃nozzles. Research results of this work can be a reference for stream limiter's design and model selection.
In order to solve the dynamic failure problem of pulverized coal pressurized conveying system, a reliability evaluation method based on dynamic bayesian network is proposed in this paper.Firstly, based on the analysis of the structure and function of the pulverized coal pressurized conveying system, the fault tree model is constructed, and the reliability analysis model of the pulverized coal pressurized conveying system is established according to the rules of the trans⁃formation from the fault tree model to the dynamic bayesian network.Then, by introducing maintenance factors and time series, using the two⁃way reasoning ability of dynamic bayesian network, the weak links and the dynamic variation law of reliability of the pulverized coal conveying system are determined.The results show that the method can effectively describe the dynamic characteristics of the pulverized coal pressurized conveying system, and the analysis results are more in line with the actual working conditions.
The organization is affected by a variety of random factors during the exercise. In order to improve the motion reliability of the mechanism, it is very important to evaluate the motion reliability at the beginning of design. The error model of collaborative robot mechanism is established based on D⁃H method and finite⁃element method. The fourth⁃order moment method is used to establish the mechanism motion reliability model. The reliability model of mechanism motion interval is established based on envelope function method. The model of rigid⁃flexible coupling parameterization with clearance is established by using ADAMS. Motion reliability simulation of collaborative robot was made with ADAMS/insight. And calculate the motion reliability within 9 s. Compared with Monte Carlo simulation（MCS）. The advantages of the fourth⁃moment method and the envelope function method in the analysis of motion reliability are proved.
In fluid pipeline leak detection and location, noise in the pressure signal collected both ends of the pipeline will affects the accuracy of leak detection and the error of leakage location. To reduce the noise interference an improved local mean decomposition (LMD) signal analysis method is proposed. The production functions (PF) that were related to the leak signal can be exacted, and it was necessary to know the characteristics of leak signals or noise in advance. According to the cross⁃correlation function, there is a significant peak between the measured signals which are decomposed into a number of PFs. These reconstructed principles PF components were obtained, and a wavelet analysis was used to remove the noise in the reconstructed signal. On this basis, the signal features were extracted according to the time⁃domain feature and waveform feature, which were input into Least Squares Twin Support Vector Machine (LSTSVM), LSTSVM to distinguished different working conditions. According to the reconstructed signal after wavelet de⁃noising, the time delay estimate of the negative pressure signal at the end of the pipeline is obtained by the cross⁃correlation function, and the leak location was ultimately calculated by combining the time delay with the leak signal propagation velocity. A leak simulation for pipeline was proposed , where the collected data of the different working conditions was processed. The experimental results show that the proposed method can effectively identify different working conditions and accurately locate the leakage point.
In the field of human interaction recognition, local features based on RGB video often cannot effectively distinguish approximate actions. The Depth image information and the color image information are merged in the recognition process, and a two⁃person interactive behavior recognition algorithm that integrates the depth information and the individual segmentation fusion is proposed.The algorithm firstly extracts the points of interest for RGB and Depth video, then uses 3DSIFT to describe the features on RGB video. The YOLO network is introduced into divide the left and right points of interest on the Depth video, and the local co⁃occurrence matrix is used for local correlation information description. Finally, the nearest neighbor classifier is used to classify the RGB features and Depth features, and further the recognition results are obtained by the decision⁃level fusion, which improves the accuracy of recognition. The results show that the combination of depth visual co⁃occurrence matrix can greatly improve the recognition accuracy of double interaction behavior, and the correct recognition rate of 90% of the actions in SBU Kinect interaction database can verify the effectiveness of the proposed algorithm.
