As an important semiconductor photocatalytic material, bismuth oxide (Bi₂O₃) is considered as a promising visible photocatalyst due to its special electronic structure and excellent visible light response performance. It displays a good application prospect in photocatalytic treatment of wastewater. However, the application of Bi₂O₃ is limited by its low photocatalytic performance, therefore, Bi₂O₃ pholocatalyst with superior performance is expected to be obtained by modifying methods by the researchers. In this review, a series of modification methods, such as surface morphology regulation, surface modification, metal ion modification and semiconductor combination, are summarized. Then, the future development of modified Bi₂O₃ photocatalytic materials is prospected.

With the rapid economic development, the demand for energy continues to increase, and the emission of CO₂ gas keep growing. The electrochemical reduction of carbon dioxide (ERC) to fuel and chemicals is an effective way to realize the conversion and utilization of CO₂ as well as the storage of renewable energy. Cu?based catalysts are one of the materials which can directly reduce CO₂ to high value?added chemicals(such as hydrocarbons) with high efficiency. Thus, the Cu?based catalysts have been one of the research focus of ERC technology research. The main research progress of Cu?based catalysts for ERC technology in recent years is reviewed. Firstly, reaction principle of ERC and the technology challenge are summarized, and then the cooperative control strategy for the structure and composition of copper?based catalysts is discussed for monometallic copper?based catalysts, polymetallic copper?based catalysts, copper oxide and oxide?derived copper catalysts, and copper?organic composite catalysts. In addition, research progress and unsolved problems of Cu?based catalysts are also summarized. Finally, the future trend these catalysts is also prospected.

In different production stages of shale gas fields, various operating conditions and parameters vary widely, and the operating conditions of the triethylene glycol dehydration unit may deviate from the optimal range, which may easily lead to insignificant dehydration effects, which will affect normal production. The HYSYS software was used to simulate the process of a 300.0×10⁴ Nm³/d shale gas triethylene glycol dehydration unit.The influence of the process parameters on the dehydration effect of the triethylene glycol such as the triethylene glycol circulation volume, the mass fraction of the triethylene glycol lean liquid, the flow rate of the feed gas into the tower, and the temperature of the feed gas into the tower,the operating pressure of the absorption tower, the temperature of the lean triethylene glycol liquid entering the tower, the total efficiency of the trays and the number of trays in the absorption tower were quantitatively analyzed.And the reasonable operating range of each process parameter was determined to achieve the best dehydration effect and meet the requirements of dry gas export. The results show that increasing the triethylene glycol circulation, lean liquid mass fraction, absorption tower operating pressure, total tray efficiency and number of absorption trays, as well as reducing the flow and temperature of feed gas into the tower, and the temperature of triethylene glycol lean liquid entering the tower are all helpful to improve the dehydration effect of triethylene glycol; increasing the temperature of the reboiler and the flow of stripping gas are beneficial to increase the mass fraction of the lean triethylene glycol. In addition, the HYSYS simulation calculation results are compared with the on?site production data. The results show that the two are basically consistent, which verifies the accuracy of the simulation calculation results, which can be used to guide actual production. The above research has certain guiding significance for improving dehydration efficiency and reducing investment cost.

The Li₂ZnTi₃O₈@polyaniline (LZTO@PANI) composite materials were prepared by sol?gel and chemical oxidation polymerization methods using tetrabutyl titanate, zinc acetate, lithium acetate and aniline as raw materials. The materials were characterized and analyzed by X?ray diffraction (XRD), infrared spectroscopy (IR), scanning electron microscope (SEM) transmission electron microscope （TEM） and electrochemical testing. The results show that the polyaniline in the composite material has an amorphous structure and no impurities are introduced. When the coating amount of polyaniline is 5.3%, the discharge specific capacity is 330.0 (mA·h)/g at 0.1 A/g. In addition, after 100 cycles, the specific discharge capacity is 281.3 (mA·h)/g.

As the greenhouse effect becomes gradually significant, CO₂ capture and storage (CCS) has turned into a potential emission reduction measure, and the adsorption method of CO₂ capture is one of the most promising technologies. Porous solid adsorbents have attracted widespread attention due to their excellent CO₂ adsorption performance. This review focused on the research of CO₂ removal by adsorption. Five different adsorption materials were introduced, and the main factors affecting CO₂ adsorption were summarized, as well as the adsorption performance of modified materials. The results show that the changes of temperature, pressure, and pore structure can affect the physical adsorption properties of the materials; reduction, oxidation, and metal ion loading modification can improve the CO₂ adsorption performance by Changing the type or number of functional groups on the surface of the material.

With the development of chemical industry, the discharge of industrial wastewater increase gradually, which has caused serious environmental pollution. Therefore, developing an efficient treatment technology to solve this problem is urgently needed. Photocatalysis is an efficient strategy to remove organic pollutants in aqueous condition. TiO2 is one of the most excellent photocatalytic material to be used in pollutant degradating, due to its higher chemical stability, photocatalytic activity and environmental friendliness. However, TiO2 particles are aggregated easily in aqueous media and difficult to be recycled, which hinders its practical applications. Dispersing TiO2 nanoparticles on the surface of mineral materials can reduce the aggregation of TiO2, increase the number of surface active sites, and improve its photocatalytic activity. This paper reviews new research progress of mineral supported TiO2 composites in photocatalytic degradation of organic pollutants.

The dust removal characteristics and working mechanism of the current four major types of dust collectors were reviewed. It mainly focused on electrostatic precipitator technology, introduced its research status at home and abroad in recent years, analyzed the influence of many different factors (equipment structure parameters, gas characteristics, dust properties) on the efficiency of electrostatic precipitator equipment, and summarized electrostatic precipitator. The current technical shortcomings of the collector: The selection of the discharge electrode, the optimization of the best parameters, the anti?corrosion and cleaning of the dust collecting plate. In the future, the following issues should be focued on: development of discharge electrode materials suitable for new forms of electrostatic precipitators, discharge characteristics and dust removal efficiency in complex atmospheres, reduced insulation performance at the dust collector, and corrosion protection.

For a long time, fabric defect detection has been completed by quality inspectors. Meanwhile, the process of defect discrimination is greatly affected by subjective factors and has the problems of low detection efficiency and high cost. With the close combination of computer vision technology and various fields, fabric defect detection system based on vision has gradually become an important solution to replace manual quality inspection. For the fabric defect detection based on vision, this paper reviews the aspects including industry development, general detection standards, overall structure of the system and key technologies in detection algorithms, introduces the existing fabric defect detection products based on vision in the market, analyzes the common defect detection standards and the basic structure of the detection system, and summarizes and compares the research status of image processing and deep learning technology in the field of fabric defect detection in recent years. Finally, the paper summarizes the key problems to be solved, and discusses the possible development direction in the future.

The paper aims to study the problem of obstacle avoidance in air?ground cooperative tracking control for the unmanned aerial helicopter (UAH),in which a new approach of designing the path obstacle avoidance plan and controller design is proposed.Initially, as for the uncertain linear UAH,by processing and judging two?dimensional environmental information within the warning range for the UAH,an obstacle avoidance strategy is proposed with the help of wall?following algorithm,and the flight angle of obstacle avoidance path and the tracking speed that can make up for bypass distance are calculated.Secondly,the proposed obstacle avoidance method is extended to the three?dimensional case,and the flight angle of the UAH is determined based on the obstacle information in the horizontal and vertical directions,which can reduce the bypass distance caused by the obstacle avoidance link as possible.Thirdly,based on two derived obstacle avoidance algorithms above,the artificial neural network (ANN) is introduced to estimate model uncertainty,and then the tracking control design schemes are established by using feedforward compensation and optimal control technologies.some simulations demonstrate the effectiveness of the proposed obstacle avoidance strategy and control algorithm.

High?speed tensile tests of HC420/780DP dual?phase steel at strain rates of 0.001，0.100，1.000，10.000，100.000 s^－1 and 200.000 s^－1 were carried out. The dynamic mechanical behavior of the materials under different strain rates was studied. The true stress?strain curves of HC420/780DP at different strain rates were obtained, and the fracture elongation, tensile strength and flow stress were analyzed. The results show that the flow stress, yield strength and tensile strength of HC420/780DP dual?phase steel increased with the increasing strain rate. Based on the modified Johnson?Cook constitutive model, the dependent plastic deformation constitutive model versus HC420/780DP dynamic strain rate was established. The fitting results of the optimized constitutive equation are in consistent with the curves of experimental results.

In this paper, the heat treatment process of carburizing and quenching of 20CrMnTi steel gear was simulated by DEFORM?HT software, and the carbon mass fraction change from the surface layer to the core after carburization was obtained. The changes in the martensite structure after quenching were analyzed, the residual stress after quenching was analyzed, the appropriate quenching cooling medium was selected, and the metallographic structure and the Rockwell hardness from the surface to the core were measured through experiments. The results show that the metallographic structure and Rockwell hardness are in good agreement with the simulation results, which have certain guiding significance for production.

The COVID?19 epidemic is facing the influence of a variety of complex practical factors, which makes the development of the epidemic uncertain. In order to overcome the problem of large error in epidemic forecasting results due to the limitations of many ideal assumptions based on the infectious disease compartment model, a time series forecasting model based on deep learning is adopted to predict the epidemic development, and an informer model based on transformer model is established. Attention mechanism and distillation mechanism are applied to the time series forecasting of epidemic data. The threshold autoregressive (TAR) model and a variety of mainstream recurrent neural time series prediction models are used as comparison models. Through simulation experiments, the current number of remaining infections in the epidemic data of China, America and Britain is predicted in the short term, and RMSE and MAE are used as evaluation indicators, and then the best model is selected for medium ? and long?term prediction. The experimental results show that the indicator value of the informer model is optimal in both RMSE and MAE, further indicating that the prediction accuracy of the informer model is higher than that of other comparative models in China, America and Britain. Finally, the Informer model is used for the development of the epidemic in China，America and Britain medium and long?term prediction.

Guaiacol (GUA) is extensively used as the model compound in catalytic studies of lignin, a most abundant renewable aromatic resource in nature. However, GUA is not easy to obtain good activity and selectivity in the hydrodeoxygenation reaction due to its complex structure with various reaction possibilities. So far, researchers have done great efforts to develop efficient catalysts and reaction processes for breakthroughs. This paper reviewed the research progress of transition metal catalysts and noble metal catalysts for hydrodeoxygenation of GUA, and discussed the reaction pathways and the factors which may affect the catalytic behavior, particularly focusing on their catalytic conversions of GUA to phenol or cyclohexanol through C_AR-O bond cleavages and aromatic ring saturation. A prospect regarding the future research directions on the catalyst improvement and reaction process optimization were also presented.

According to the characteristics of the canteen, the FLACS software was used to build a three?dimensional model for a university canteen. On the basis of considering the jet direction, obstacles and other factors, the leakage and explosion of natural gas were simulated, and the diffusion process of gas cloud, the development law of explosion shock wave and temperature in a specific scene were studied. The results show that when the gas leaks vertically upward, the gas accumulates in the small booth due to the obstruction of the canteen roof. When the natural gas leaks horizontally, the volume fraction of natural gas cloud in the dining area is higher. At the initial stage of the explosion, the explosion pressure shock wave centered on the ignition point first appears, and the pressure shock wave travels outward in a circular arc. The leakage direction has little effect on the maximum over pressure generated by the explosion.The temperature distribution is greatly affected by the direction of leakage. When vertical injection is carried out, the high temperature is concentrated in the small booth. When horizontal injection is carried out, the temperature is distributed from high to low.

Titanium sulfate was used as a raw material, and a titanium oxide (TiO₂) was prepared by direct high?temperature calcination in a muffle furnace. FT?IR, XRD, UV?Vis, SEM were used to characterize the structure of the catalyst. The results show that the direct calcination method can prepare anatase titanium dioxide and apply it to the oxidative desulfurization of dibenzothiophene. Using acetonitrile as the extractant and titanium oxide as the catalyst, the oxidation method was used to remove dibenzothiophene from the simulated oil. The effects of catalyst dosage, reaction temperature, n(H₂O₂)/n(S), and different sulfur compounds on the desulfurization effect were investigated, and the recycling performance of the catalyst was also investigated. Under the optimal desulfurization conditions, the desulfurization rates of dibenzothiophene, 4,6?dimethyldibenzothiophene, benzothiophene, and mixed diesel are 99.5%, 35.6%, 65.0%, and 53.4%. After the catalyst was recycled five times, the catalytic desulfurization effect was still as high as 90.3%.

This paper summarized the separation effects of different electrodialysis systems on lithium in Salt Lake, including single selective electrodialysis, ionic liquid membrane and bipolar membrane, among which ionic liquid membrane with a broad development prospect possesses the characteristics of high recognition of Li⁺, long?term stability under electrolysis and low energy consumption. Furthermore, the advantages, disadvantages and tendency of prospective development of different electrodialysis systems in lithium extraction from Salt Lake were analyzed, and the industrialization research on the application of electrodialysis systems for lithium extraction from Salt Lake was analyzed.

In recent years, light?emitting organics have attracted widespread attention due to their unique functions. Among them, room temperature phosphorescent organics have the characteristics of longer wavelength and long life due to their triplet excitons and relatively slow decay rate, resulting in a wide range of application prospects in optical devices, photocatalytic reactions and other fields. At present, the construction of room temperature phosphorescent organic system is mainly accomplished by promoting spin?orbit coupling and suppressing the non?radiative decay process from the triplet state to the ground state. This article summarized the development of room temperature phosphorescent organic system in recent years. According to how to design room temperature phosphorescent organic system, several methods were proposed and their principles were analyzed, and the future development and application of room temperature phosphorescence organic system were prospected.

With the improvement of environmental uncertainty, the demand for supply chain stability of petrochemical enterprises in China is rising day by day. The evaluation of supply chain resilience of petrochemical enterprises has become an important means to judge the risk coping ability of petrochemical enterprises. This paper constructs a supply chain resilience evaluation index system in the petrochemical enterprises. And fuzzy analytic hierarchy process and BP neural network are used to evaluate the toughness strength of petrochemical enterprise supply chain, so as to determine the toughness level of petrochemical enterprise supply chain.It is found that the strength of supply chain toughness of petrochemical enterprises is uneven, and the overall level of supply chain resilience is low. On the basis of the research results, some practical suggestions are put forward for the forging of resilient supply chain in petrochemical enterprises.

Chiral oxazolines are a type of important chiral heterocycles compound, which are not only present in many biologically active natural products and drug small molecules with physiological activity, but also in chiral cofactors and chiral ligands often used in chiral synthesis. Currently, the asymmetric synthesis of chiral oxazolines still relies on the condensation between chiral amino alcohols and carboxylic acid derivatives. However, due to the limited availability of chiral amino alcohols and the tedious synthetic route, the development of highly efficient and straightforward methods for chiral oxazolines synthesis via asymmetric catalysis is of significant synthetic value. In this paper, we have summarized the recent advances in the asymmetric catalytic synthesis of chiral oxazoline derivatives through transition metal catalysis and organocatalysis, including asymmetric Aldol reactions, asymmetric clizations and others.

A modified dicyandiamide?formaldehyde decolorizing flocculant was prepared using cyclohexylamine as modifier, and was used to simulate dye wastewater decolorization, flocculation and sedimentation experiments. The effect of reaction temperature, reaction time, material molar ratio and other factors on the decolorization performance of the modified flocculation was studied. The results show that reaction time is 3.5 h, reaction temperature is 85 ℃, material molar ratio of dicyandiamide to formaldehyde to ammonium chloride to cyclohexylamine is 1.00∶3.00∶0.50∶0.15, the decolorization rate 88.6% is achieved at a modified flocculant dosage of 100 mg/L. The decolorization and flocculation performance of the dicyandiamide?formaldehyde modified decolorizer is obviously better than that of the unmodified product.

Magnetic tomography method has been widely used for nondestructive external inspection of buried and submarine pipelines, which is based on the principle of metal magnetic memory to discern the danger level and location of the stress concentration zone by measuring the anomalies in the spatial magnetic field distribution outside the pipeline. The distribution characteristics and spatial propagation law of pipeline inspection signal detected by magnetic tomography method, the energy distribution and change law of spatial magnetic memory signal in the stress concentration zone of magnetized pipelines are studied in this paper. The magnetic dipole field is used to establish the magnetic field model in the stress concentration zone of the inner wall of the pipeline, and the magnetic energy and energy density of spatial magnetic memory signals under different lift?off values outside the pipeline are finite element calculated based on the magnetic energy theory to derive the distribution law of spatial magnetic field and the correlation of magnetic energy density of magnetic signals under different lift?off value is analyzed. The results show that the spatial magnetic field energy outside the pipe decays with the increase of lift?off value, and the decay is the fastest within the distance of 50 mm from the outer wall of the pipe to the physical force; the correlation of magnetic energy density of different lift?off values shows that the magnetic signal detected by magnetic tomography method outside the pipe is homologous with the signal in the stress concentration zone of the inner wall of the pipe. Theoretically, it explains the effectiveness of magnetic tomography method and also provides evaluation indexes for extracting effective signals from the detection data.

Li₂ZnTi₃O₈ (LZTO) anodes of lithium?ion batteries have been prepared by a sol?gel method. The effects of the calcination temperature and time on the electrochemical performance have been studied for LZTO in detailed. The optimum calcination temperature and time are 700 ℃ and 3 h, respectively. On the basis of the optimum preparation process, citric acid as the chelating agent has been introduced into the synthesis to modify LZTO. When the molar ratio of metal ions to citric acid is 2.00∶1.50, the obtained product is denoted as LZTO?2/1.50, which has small particle size, good dispersion, and then shows good electrochemical performance. The discharge specific capacity is 203.6 mA·h/g after 300 cycles at the current density of 0.5 A /g for LZTO?2/1.50.

The data of chemical processes often contains dynamic timing characteristics, and traditional fault detection has low usage of dynamic information, which limits the fault diagnosis performance. To address this problem,a new method of chemical process fault diagnosis based on an attention?enhanced encoder?decoder network model (AEN) was proposed. The coding part uses the LSTM to extract the feature information of the process data and combine it with the attention mechanism to utilize the dynamic information among the process data more effectively； the decoding part uses the LSTM and combines the context vector provided by the attention mechanism to provide more accurate state information for the softmax regression, and finally, the softmax regression is used to obtain the probability value of the fault category for each sample data. The introduction of the attention mechanism improves the efficiency of the model in using process dynamic information in the time domain. The proposed method is experimented with using Tennessee Eastman process data and compared with the results of standard PCA?SVM, DBN and ResNet, and the results show that the proposed method is more effective in diagnosing faults.

Thiacalix[4]arene ligands have the advantages of high recognition, derivatization, excellent stability and other advantages. Lanthanide (Ln) ions can coordinate with thiacalix[4]arene ligands to form multi?functional coordination clusters, which received increasing attention due to their unique catalytic, magnetic, optical properties. Thiacalix[4]arene can sensitize Ln ions to luminescence by the coordination of phenol and S groups via the "Antenna effect". This paper reviewed recent advances in structures, luminescent properties, and applications of luminescent Ln?thiacalix[4]arene complexes.

The Fe/Mo ordering at B?sites of Ba₂FeMoO_6-δ (BFM) were changed by adjusting Fe/Mo amount of substance ratio (i.e., stoichiometric ratio), and then a new double?perovskite anode material Ba₂Fe_1.3Mo_0.7O_6-δ (BFM_0.7) for SOFC were obtained. The results indicated that the electrical conductivity of the BFM_0.7 anode is 15.0~20.0 S/cm at 600~800 ℃ in H₂, which is much larger than that of the lowest target for SOFC electrode (0.1 S/cm). The peak power density and polarization resistance of the BFM_0.7 anode cell attained 1 149 mW/cm² and 0.15 Ω·cm² at 850 ℃. Compared with BFM anode, the performance of BFM_0.7 is significantly improved. In addition, the performance of BFM_0.7 anode cell showed no degradation after testing for 39 h, indicating that the BFM_0.7 anode possesses has excellent electrochemical stability.

Monolayer Janus transition metal disulfides have low dimension, high mobility, and peculiar electronic structure properties, which have potential applications in electronics and optoelectronic devices. In devices made of monolayer Janus transition metal disulfide and substrate materials,are usually stressed due to lattice mismatch between monolayer Janus transition metal disulfides and substrate, it is significant to study the strain effect on physical properties of monolayer Janus transition metal disulfides through Raman scattering.This paper systematically investigate the biaxial strain effect on the atomic structure, electronic structure and Raman spectra of monolayer Janus MoSSe. The results show that monolayer Janus MoSSe can exhibit a band gap transition from direct to indirect one under biaxial strain, due to both the energy shift of bonding orbitals between the top of the valence band and the bottom of the conduction band and the sensitivity to strain. This paper also thoroughly study the strain effect on the Raman shift and intensity of monolayer Janus MoSSe. It is found that under biaxial strain modulation from decreasing compressive to increasing tensile, for the Raman shift, the three peaks of E¹, E², and A {}_{\mathrm{1}}^{\mathrm{1}} red?shift, while the peak of A {}_{\mathrm{1}}^{\mathrm{2}} blue?shifts abnormally with decreasing compressive strain; for the intensity, the peak intensity of the doubly?degenerate modes (E¹,E²) increases monotonically, while singly?degenerate modes shows the opposite trend, except for the A {}_{\mathrm{1}}^{\mathrm{1}} which intensity decreases with decreasing compressive strain and then increases with tensile strain. This paper propose a simple model to comprehend the strain effect. This theoretical study may supply an effective means to quickly and quantitatively characterize the strain size and type in Janus materials through the frequency difference and intensity ratio between typical Raman peaks.

Hierarchical porous Hβ molecular sieve with different structure and acidity were prepared by alkali treatment. XRD, SEM, N₂ physical adsorption and NH₃?TPD characterization methods were used to characterize molecular sieves before and after alkali treatment. With hierarchical porous Hβ molecular sieve as the carrier, the Ru?Hβ bifunctional catalysts were prepared by an equal volume impregnation method, and the benzene hydroalkylation reaction activity and stability were evaluated in a fixed bed reactor.The results show that Hβ molecular sieve can effectively increase the proportion of mesopores after being treated with a proper concentration of alkali, which is beneficial to improve the hydroalkylation activity and stability. At 2 MPa, 210 ℃ and a liquid hourly space velocity of 1 h^-1, when the Ru mass fraction is 0.2% (based on the mass of hierarchical porous Hβ molecular sieve), the dual?functional catalyst composed of hierarchical porous Hβ can achieve effective and stable operation. At the same time, the conversion rate of benzene is 54.32%, the selectivity of cyclohexyl benzene is 71.47%, and the stability of the catalyst does not decrease significantly within 280 h.

With the development of artificial intelligence technology and big data Internet technology, the pipeline leak detection technology is developing in the direction of intelligence. Based on the classification of continuous pipeline leak detection technology and discontinuous pipeline leak detection technology, this paper introduced the principles of various leak detection methods, summarized and analyzed the research status of long?distance oil pipeline leak detection technology at home and abroad. The application of combined oil pipeline leak detection and location technology in long?distance oil pipeline detection was prospected.

In recent years, the sales volume of the automobile industry, which is the backbone of the national economy, has been declining, and the financial leverage ratio has continued to rise. In order to improve the profitability of automobile manufacturing enterprises, this paper used SPSS 26.0 and Excel 2010, collected the financial data of 145 auto A?share listed companies in Shanghai and Shenzhen from 2017 to 2019 as samples to conduct an empirical analysis and test of the relationship between corporate leverage ratio, corporate growth ability and profitability. The results show that there is a negative correlation between leverage ratio and profitability, positive correlation between corporate growth ability and profitability, negative correlation between corporate leverage ratio and growth ability, and there is a certain intermediary effect in the influence of corporate growth ability on profitability.

In view of the irregularity of the bottom floor of working face and the diversity of the shape of the flying gangue in steeply dipping coal seam, based on the geographic information system data such as contour line of bottom floor of working face, the 3d grid model of bottom floor is established, combined with the energy tracking method(ETM) C + + programs, four typical shapes of flying gangue with the same mass and different shapes are simulated to obtain the motion trajectories of the migration of flying gangue in the actual working face, as well as the velocity, angular velocity and energy change curves at any time. The influence of the shapes on the motion of flying gangue is analyzed. In order to verify the accuracy and feasibility of the method in this paper, the trajectory simulated by Rockyfor3D software is compared. The results show that the transport capacity of ellipsoidal flying gangue is much higher than that of polyhedral flying gangue. Compared with common polyhedral flying gangue, the regular polyhedral flying gangue has farther migration distance and less energy loss due to collision. The number of edges of flying gangue of regular polyhedron is inversely proportional to the energy loss of flying gangue in collision, which indicates that flying gangue of regular polyhedron with multiple edges is most likely to cause danger．

Pollution caused by petroleum?based plastic products has become a problem that is difficult for human beings to solve, and the existing treatment methods are both energy?consuming and easy to cause secondary pollution. The study found that the bacteria that degrade plastic in the intestines of Galleria mellonella (Lepidoptera: Pyralidae) larvae can effectively accelerate the degradation of plastics. This experiment uses polystyrene (PS) packaging boxes, which are common in life, as the only food source to feed the larvae of the large wax borer, enriching the PS?degrading bacteria in the intestines of the G. mellonella larvae. After dissection, culture, and isolation, four strains were obtained: PD?1, PD?2, PD?3 and PD?4. The degradation capacity of MSM culture medium with PS film as the only carbon source was inoculated with each strain, and the degradation rate of PD?1 on PS film was the highest, which was 1.8%. PD?1 was observed by strain morphology, physiological biochemical determination and phylogenetic tree construction, and it was identified as Enterobacter colebella (Klebsiella). Meanwhile, the method of UV and nitric acid pretreatment of PS film were used to improve the degradation rate of the strain, and the results showed that the weight loss rate of PD?1 degradation of nitric acid?treated PS film was improved, which was 2.5%, while the UV group was 0.8%, indicating that PS film was more easily degraded by PD?1 after nitric acid treatment.

Recognition of weather phenomena based on images is essential for the analysis of weather conditions. To address the problems that traditional machine learning methods are difficult to accurately extract various weather features and poor in classifying weather phenomena and the accuracy of deep learning for weather phenomena recognition is not high, a weather recognition model based on image block and multi?headed attention mechanism is proposed. The model introduces Swin Transformer into the field of weather recognition for the first time, and adopts a multi?headed attention mechanism combining window multi?head self?attention layer and shifted?window multi?head self?attention layer, whose regionally relevant features extraction capability makes up for the shortcomings of traditional methods and can extract complex weather features from images. The model is trained using transfer learning, and the fully connected parameters of the fine?tuned model are input to the Softmax classifier to achieve recognition of multi?category weather images with 99.20% recognition accuracy, which is better than several mainstream methods in comparison, and it can be applied to ground weather recognition systems as a weather recognition module.

Gasoline molecular blending technology on?line requires rapid access to detailed molecular composition information of various types of component oils. In this paper, an autoencoder?based method for the rapid resolution of gasoline molecular composition is developed, which can directly predict the detailed monomeric hydrocarbon composition of gasoline from near?infrared spectra. The constructed autoencoder model of gasoline molecular composition can explore the potential features and recover the original molecular composition by decoding the potential features. The artificial neural network algorithm is used to correlate the NIR spectral information with the potential features of gasoline composition. The accuracy of the model is verified by using hydrogenated gasoline with the average absolute error is 0.033. The model developed in this work applies the current popular autoencoder algorithm to the traditional petrochemical process, which is an important guideline for blending online and real?time optimization of gasoline molecules.

Polylactic acid/Poly(butylene adipate?co?terephthalate)/Poly(methyl methacrylate)?b?poly (butyl acrylate)?b?poly (methyl methacrylate)ternary blends (PLA/PBAT/MAM) were prepared by melt blending, and the effect of MAM relative molecular weight on the morphology, structure and properties of the blends was investigated. The results showed that the addition of MAM block copolymer can inhibits the crystallization of PLA，improve the compatibility of PLA/PBAT, reduce the particle size of the dispersed phase and make the distribution more uniform, improve the impact properties and elongation at break of the blends. And the relative molecular weight of MAM increased, the impact strength and elongation at break of the blend increased, the smaller the size of the dispersed phase particles, and the more uniform of particle size distribution.

Heterocyclic N?oxides are important structural units in organic synthesis and pharmaceutical molecules. Under mild conditions, the combination of visible?light catalysis and transition metal catalysis can simply and efficiently realize the direct ortho?C—H bond acylation reaction of heterocyclic N?oxides and benzoyl formic acid. The reaction system has good universality and excellent selectivity, and can obtain a series of N?oxides substituted by ortho?acyl groups at a moderate to good yield.

Ozone is a clean and strong oxidant, which has been widely used in the degrading of organic pollutants. However, the ozone oxidation process alone is not ideal for the treatment of difficult?to?degrade organic pollutants in water. Therefore, ozone catalytic oxidation technology came into being, and the selection of catalyst is the key factor to determine its degradation effect. Based on the various types of catalysts, the mechanism of metal oxides, carbon?based materials and supported composite catalysts for the catalytic oxidation treatment of water pollutants by ozone was reviewed. The existing problems and the main problems that need to be solved at present were analyzed to provide theoretical basis and reference for the research and development of suitable catalysts.

High?nuclear silver clusters have recently received increasing attention owing to their interesting electronic structures and diverse geometric structures. According to Lewis acid?base theory and coordination chemistry theory, silver ions, as acidic centers that provide empty orbitals, often combine with organic ligands that carry lone pairs of electrons as basic centers to form stable coordination compounds. Alkynyl, thiol, and organic phosphine ligands have been widely used to coordinate with silver(I) ions to form silver clusters with various structures. This paper introduced the research progress of the silver chalcogenide clusters constructed by tert?butyl mercaptan ligand, as well as the synthesis methods and structures of silver chalcogenide clusters with different configurations, and explored its potential luminescence and electrochemical properties. The application prospects and development directions of silver chalcogenide clusters was prospected.

Billets have oxidized layers and defects on their surface due to the production process, so they must be surface?regulated by grinding. There is no special equipment for surface regrinding of large square steel billets; a square steel regrinding equipment was designed. Kinematic simulation verification was completed using ADAMS software. The results show that the regrinding equipment can simultaneously and smoothly complete the grinding operation on two adjacent surfaces. Using finite element software ANSYS to carry out stress analysis and modal analysis of the regrinding machine under load, and improve the structure; according to the simplified kinematic model, static analysis was carried out to get the required input driving torque, and the selection of the critical components of the spring was completed. Theoretical calculations and simulation results show that this regrinding machine can efficiently grind the surface of large square billets.

Aiming at the bond?slip behavior of reinforced concrete, the finite element model of reinforced concrete bond?slip based on cohesion model was constructed by ABAQUS finite element software. The mesh sensitivity and cohesion parameter sensitivity of the simulation model were explored by energy and load?displacement curves. Aiming at the problem of bond strength of reinforced concrete, a nonlinear autoregressive exogenous network (NARX) was developed to predict the load?displacement curve for reinforced concrete by creating 20 sets of data with the variables of bond length, reinforcement diameter, and loading method. The study shows that the mesh size of 6 mm provides an ideal balance between prediction accuracy and computational cost. Based on the sensitivity of the finite element prediction results, the cohesive parameters are in the sequence of damage initiation strength, fracture energy, and stiffness. The NARX with the prediction accuracy of 99.6% is promising to replace time?consuming numerical simulations and experimental works to achieve an efficient and accurate prediction of the bond strength of reinforced concrete. Such an efficient and accurate prediction method provides a novel and convenient methodology of predicting and designing the bond strength of reinforced concrete.

Thermogravimetric analysis (TGA) was used to study the thermodynamic behaviors of pyrolysis and incineration of six typical components of MSW, and to explore the interaction between PVC which is the dioxin precursor and other components of MSW. The effects of different components on promoting or inhibiting the decomposition of PVC were quantitatively analyzed by combining the calculation of superposition rate of calculated curve and experimental curve and the fitting of kinetic parameters. The results show that adding paper, wood chips, cardboard and PE can reduce the formation of dioxin in PVC incineration process, and PE has the best inhibition effect on the formation of dioxin.

The aero?engine clamp has an assembly constraint relationship with the pipeline, and its layout position has an important influence on the direction of the pipeline and the vibration performance. An optimization method of engine clamp position adjustment based on improved Grey Wolf Optimization (GWO) was proposed. Based on the existing pipe?clamp geometric layout scheme, this method takes the adjustment of the natural frequency of the pipe?clamp to avoid resonance as the main optimization goal, takes the pipeline obstacle avoidance and the pipeline?clamp meeting assembly constraints as constraints, and applies the improved GWO algorithm to carry out the secondary optimization and adjustment of the clamp position. In order not to affect the geometric layout of the pipeline, an optimized space for the position of the clamp based on the pipeline projection line was established. In order to improve the efficiency of optimization calculation, the Kriging surrogate model reflecting the position of clamp and the natural frequency of pipeline was established to replace the time?consuming finite element calculation program in the optimization process. In order to improve the search performance of GWO, a GWO algorithm with improved convergence factor was proposed. This method can optimize the position of the clamp under the premise of ensuring the fine adjustment of the pipe geometric layout, and can ensure that the pipe and clamp meet the assembly constraints. Finally, the effectiveness of the proposed method was verified by the test function example and the clamp arrangement example.