Table of contents

It is highly delighted to introduce the proceedings dedicated to the 2021 3rd International Conference on Polymer Synthesis and Application (ICPSA 2021), which was planned to be held on July 23-25, 2021 in Nanjing, China. In light of worldwide travel restriction and the impact of COVID-19, ICPSA 2021 was carried out in the form of virtual conference to avoid personnel gatherings. Because most participants were still highly enthusiastic about participating in this conference, we chose to carry out ICPSA 2021 via online platform according to the original schedule instead of postponing it.

ICPSA 2021 provided an enabling platform for innovative academics, engineers and industrial experts in the field of synthesis and application of polymer to exchange new ideas and present research results. This conference also promoted the establishing of business or research relations among global partners for future collaboration. We hope that this conference could make significant contribution to the update of knowledge about these latest scientific field.

List of Committee member is available in this pdf.

All conference organisers/editors are required to declare details about their peer review.

Therefore, please provide the following information:

• Type of peer review: Double-blind

• Conference submission management system: AI Scholar System

• Number of submissions received: 165

• Number of submissions sent for review: 159

• Number of submissions accepted: 91

• Acceptance Rate (Number of Submissions Accepted/Number of Submissions Received X 100): 55.2%

• Average number of reviews per paper: 2

• Total number of reviewers involved: 50

• Any additional info on review process:

• Step 1. Each of selected paper will be reviewed by two/three professional experts in the related subject area.

• Step 2. Review Reports received from the experts will be judged by one of the editors either Review Reports are logical or not?

• Step 3. If not logical, then editor can assign new reviewer or can also judge at his/her own.

• Step 4. If logical, then Review Reports will be sent to authors to modify the manuscript accordingly.

• Step 5. Authors will be required to revise their papers according to the points raised.

• Step 6. Revised version will then be evaluated by the editor for the incorporation of the points raised by the reviewers.

• Step 7. Then the editor will send the revised manuscript to the reviewers again for re-evaluation.

• Step 8. If the reviewers approve the revise version of the manuscript, then will be accepted for publication.

• Contact person for queries:

Xuexia Ye

publication@keoaeic.org

AEIC Academic Exchange Information Centre

As a typical multi-component polymer, impact polypropylene copolymer (IPC) experiences the phase structure evolution during repeated processing, and the coarsening of phase domain often occurs. In this work, two IPCs with different molecular weight of rubber phase were compared systemically. The evolution of IPC phase morphology and crystallization behavior after multiple extrusion were studied through scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). The materials mechanical properties were tested. Then the influence of rubber phase molecular weight on the phase morphology evolution and the properties after repeated extrusion were discussed in detail. It was found that for the IPC with low molecular weight of rubber phase, the size of rubber phase became smaller and dispersed more evenly with the increase of extrusion times; for the IPC with high molecular weight of rubber phase, the rubber phase size turned to unstable after multiple shearing. The rubber phase size had a complex effect on IPC mechanical properties.

With the increase in the speed of various aircraft and the demand for lightweight weapons and equipment, the demand for high-performance, high-temperature-resistant resin-based composite materials has become more urgent. The temperature resistance and molding process of composite materials are determined by the temperature resistance and manufacturability of the resin, so there is an urgent need to develop a resin that has both high temperature resistance and excellent process performance. The temperature resistance and processability of the resin are essentially determined by the molecular structure of the resin system. Therefore, in order to design a resin system with excellent heat resistance and processability, the relationship between molecular structure and performance must first be recognized. This paper collects a large amount of experimental data and preliminarily summarizes the influence of different molecular structures on the thermal performance and resin processability of resin polymers from the perspective of structure and performance. This provides a good experience and theoretical basis for the design of high-performance resin systems, providing references and ideas for related research.

The molecular structure and mechanical properties of 3 kinds of imported polypropylene particles for capacitor film were analyzed by Gel Permeation Chromatograph (GPC), differential scanning calorimeter (DSC) and electronic tensile machine. The results showed that the melt index of imported polypropylene for capacitor film was about 3.0g/10min, the ash content was about 20ppm, the isotacticity index was higher than 98.5%, the crystallinity was higher than 45%, and the molecular weight distribution was wider than 6.0. The data showed these three kinds of imported polypropylene for capacitor film were all low-ash and higher isotactic polypropylene with high crystallinity and good mechanical tensile properties.

Steel slag micro powder is steel slag after special process grinding, is a by-product in the process of steel production. This paper studied the basic mechanical properties and crack control ability through the compression strength test (0,8%, 14%, 20%) by compressive strength test and four-point bending test of thin plate. The results show that the inclusion of steel slag has a negative effect on the compressive strength of high toughness cement base composite and not against folding strength. When the steel slag powder reaches 20%, the test matrix can still show large toughness characteristics and crack control capacity.

Multi-walled carbon nanotubes (MWNTs) were used to adsorb low concentration erythromycin from natural water. The kinetic curves and adsorption isotherms were measured and the thermodynamic parameters were calculated. The effects of pH value, ionic strength and humic acid on the adsorption process were investigated. The results showed that the adsorption of carbon nanotubes to erythromycin was rapid in the first 40 min, and reached equilibrium within 200 min. The dynamics curve conforms to the quasi-second-order dynamics model. The Freundlich model can better fit the adsorption test data. Thermodynamic parameters show that the adsorption of Erythromycin by MWNTs is a spontaneous endothermic process. The adsorption activation energy Ea shows that the adsorption between MWNTs and erythromycin is a chemisorption process, and the content of oxygen-containing functional groups on the surface of CNTs determines the equilibrium adsorption amount. Ionic strength has obvious effect on adsorption. Increasing the pH value of the solution from 5 to 9 was beneficial to increasing the adsorption capacity of erythromycin. The adsorption capacity of carbon nanotubes to erythromycin was significantly increased with appropriate humic acid.

In order to obtain the natural frequency and vibration mode of concrete-filled steel tube (CFST) arch bridge with different parameters, the modal analysis of a double-span arch bridge with a total length of 257.4 meters and a full width of 31.8 meters is carried out. By controlling the three variables of concrete strength, steel tube thickness and the number of transverse braces in arch ribs, the regularity of the natural frequency and vibration mode of CFST arch bridge with different variables is discussed. The results show that with the increasing of the strength of concrete-filled steel tube in arch ribs, the fundamental frequency increases gradually. The vertical stiffness of the arch bridge is positively related to the thickness of the arch rib steel pipe. The fundamental frequency of the arch bridge can be improved by setting transverse brace, and the change of the number of transverse braces has a significant effect on the sixth-order natural frequency. It is limited for the arch bridge to improve the stiffness by changing the number of transverse braces. These can lay the foundation for the dynamic response analysis of the CFST arch bridge.

The mixed refrigerants have a great potential in the energy industry, while the micro-mechanism of evaporation of mixed refrigerants is still unclear. Therefore, molecular dynamics simulations were employed to investigate the evaporation of the R32, R1234yf and their mixture on the Pt surface at 230 K, 250 K and 350 K, respectively. The results indicate that the presence of R1234yf will suppress the evaporation of R32. The adsorption interaction between R32 and substrate is lower than that of R1234yf. The film boiling is found at high temperature evaporation. Meanwhile, the heat flux of the system decreases due to the heat transfer deterioration.

Sm-doped Ni-Al layered double hydroxides (LDHs) were successfully prepared via hydrothermal-assisted coprecipitation method. The structure and surface morphology of the samples were characterized by X-ray diffractometer (XRD), Fourier transform infrared spectrometer (FT-IR) and scanning electron microscope (SEM). The electrochemical performance of the samples as prepared was measured by cyclic voltammetry (CV), galvanostatic charge/discharge (GCD) and electrochemical impedance spectroscopy (EIS). These results show that Sm-doped Ni-Al LDH exhibit higher specific capacitance 2177 F⋅g^-1 at a current density of 1 A⋅g^-1, compared with pure Ni-Al LDH with a specific capacitance 1312 F⋅g^-1 at same current density.

Hydrotalcite inorganic fillers with different metal ratios were synthesized by coprecipitation method and hydrothermal method. The hydrotalcite inorganic fillers/polylactic acid composites (HT/PLA) were prepared by melt blending method. The mechanical properties, flame retardancy and thermal properties of the composites were investigated. The results show that HT inorganic filler was successfully prepared by coprecipitation method and it had typical HT structure. Compared with pure PLA, the impact strength and bending strength of HT/PLA composites decreased. The tensile strength, elongation at break, bending strength and tensile modulus of elasticity of the self-made M-Mg/Al-HT/PLA composite were better than those of the purchased C-Mg/Al-HT/PLA composite. The oxygen index of HT/PLA composites increased obviously, and the oxygen index of HT/PLA composites increased with the increase of the amount of HT. Different kinds of HT/PLA composites have different flame retardancy, and the order is Cu/Mg/Al-HT/PLA>Co/Mg/Al-HT/PLA>Ni/Mg/Al-HT/PLA>Mg/AlHT/PLA>Zn/Mg/Al-HT/PLA. The plasticity of HT/PLA composite is higher than that of pure PLA, and its thermal stability is better.

The operation performance of biofilm system is limited by the oligotrophic quality of source water, especially the bioavailable organics. In this study, two lab-scale biofilm reactors (R₁ and R₂) feeding different organic carbon sources (OCS) were built up using sediment in drinking water source as bacterial source. Experimental results showed that sediment in biofilm systems enhanced the NH₄⁺-N removal performance. Using ethanol as OCS was more beneficial to the removal of NH₄⁺-N with ammonia removal efficiency (ARE) of 87.0 ± 5.4%, which was higher and more stable than that of glucose with ARE of 83.9 ± 13.3%. Organic carbon source changed the bacterial structure in biofilm systems. The dominant phyla in biofilm under ethanol condition were Proteobacteria, Bacteroidetes and Firmicutes with relative abundances (RA) of 29.1%, 32.7% and 22.0%, respectively. The dominant phyla in biofilm exposure to glucose was Proteobacteria with an RA of 63.4%. At genus level, Nitrospira, Lachnospiraceae, Arcobacter and Hyphomicrobium were dominant under ethanol condition (R₁) with the total relative abundance of 20.5%. Sphaerotilus was the dominant genus under glucose condition (R₂) with RA of 33.72%. These dominant bacteria were basically having the ability for the removal of nitrogen and organic matter.

In this paper, atmosphere plasma spray (APS) is used to prepare WC/Ni coating on 1Cr18Ni9Ti stainless steel to enhance the wear resistance of materials of the axial-flow fan. The phase composition and microstructure of the spraying coating were analyzed, and the tribological properties of the coating were investigated through the ball-disk point contact sliding dry friction test. The results show that the spray powder is melting and spreading well by using nickel coated tungsten carbide powder as the spray powder combined with APS technology. The as-sprayed WC/Ni coating has a dense structure, slight oxidation. The hard phase tungsten carbide is evenly distributed and the interface of the bonding phase nickel is well combined with tungsten carbide. The microhardness of the coating cross-section can reach 655±90HV_0.3. In the point contact wear test with high contact stress, tungsten carbide particles are pinned to the friction surface, which greatly improves the resistance to abrasive wear. The coating wear rate is only 2.42×10^-6mm³⋅N^-⋅m^-1, and the anti-wear of the coating is about 136 times that of Inconel718 alloy under the same friction condition. The dry friction and wear mechanism of the WC/Ni coating are manifested as surface fatigue scale peeling. The large pieces of tungsten carbide particles are prevented from being pulled out and peeled because of the crushing of tungsten carbide particles and the bonding effect of nickel. And the anti-wear of the coating has not deteriorated due to fatigue during the high friction cycle.

Geotextiles are classified into various types which are Synthetic staple fibers needle-punched nonwoven geotextiles, Synthetic filament spunbond and needle-punched nonwoven geotextiles, Synthetic filament woven geotextiles, Slit and splitfilm yarn woven geotextiles, Plastic woven film yarn geotextile based on different weaving methods and property parameters. The applicability of wide-width strip method and narrow strip method for testing the tensile properties is compared and analyzed.

SMA-5 Ultra-thin Overlay is a kind of preventive maintenance material which has the advantages of fast construction, good surface texture depth, cost-effective and environmentally friendly. It is also suitable for the maintenance of bridge and tunnel which have restriction on elevation. However, the insufficient durability is the key factor which restricts the development of SMA-5. This article summarizes the key technology to enhance the durability of SMA-5 in terms of its material composition, grading and mixture design methods, which provide a reference for improving the durability of SMA-5 and promoting the application of SMA-5.

Aiming at the Beijing 2022 Winter Olympic Games, a new type of steel-wood combination sunshade structure system was proposed, and its selection was analyzed. The related joint forms were studied, and the new joint forms were put forward. The mechanical performance of the new joint was analyzed through tests and finite element simulation.

Taking a 110 kV transmission line as the research object, a refined finite element model of three pole two line transmission tower line system is established.Considering collision and contact between a dropped wire and ground, nonlinear dynamic analyses of the system with different break points and different numbers of broken wires were performed. The results showed that the break point location has little effects on the impact action of broken wire; the tension decay coefficient of the broken wire decreases with increase in the height of the hanging point position, while that of the unbroken wire decreases first and then increases with increase in the height of the hanging point position. The initial pretension, wind direction angle and span of the cable are selected for parameter analysis. The influence of these parameters on the nonlinear dynamic stability critical load of the hollow mezzanine concrete pole line system is investigated.

The effects of different additives on mechanical properties of acrylic were studied by orthogonal test, using methyl methacrylate as raw material, concentration of initiator(azobisisobutyronitrile), plasticizer (Dibutyl Phthalate) and release agent(Stearic Acid) as the influence factors. The results show that: among the three additives, initiator is the most significant factor, which has the greatest impact on the mechanical properties of acrylic. With increasing of initiator content, the tensile strength of acrylic decreases. The effect of plasticizer and release agent on the mechanical properties of acrylic is relatively small. As the increase of plasticizer content, the tensile strength and bending strength decline. Finally, the best ratio of the three additives is initiator=0.06, plasticizer=3.0, release agent=1.0.

In this study, the feasibility of aerobic granular sludge formation without inoculated sludge was detected. After 10 days operation, AGSs were discovered in reactor and the MLSS and settling ability of AGS enhanced gradually. After 21 days operation, the effluent NH₄⁺-N and COD keep low than 10 and 100 mg/L, respectively. During the formation of AGS, the content of EPS gradually increased and remained stable. Microbial community showed that EPS secretion genera (such as Paracoccus, Flavobacterium and Thauera) were main genera in AGS.

To assess the factors affecting the formation of heterocyclic amines (HAs) in sauced pork, an orthogonal experiment about fat content, braising time and the number of braising times was designed, and the effects of common seasonings and seven Chinese spices on HAs formation were conducted. It was found that higher fat content, increasing braising time and the number of braising times would promote the formation of HAs. Sugar, salt and spices exhibited a reduction in HAs formation in sauced pork. 0.01% of clove could inhibit the formation of HAs by 36.21%. Notably, the inhibitory effect on HAs was significantly correlated with the concentration of spices.

Polyester fabric has compact molecular chain structure, high crystallinity, no hydrophilic groups except hydroxyl groups at both ends, and poor hygroscopicity. The surface of polyester fabric was modified with acrylic acid by ultraviolet light in order to improve its hydrophilicity. The best technological conditions are as follows: the concentration of acrylic acid is 10%, the irradiation time is 1 hour, and the concentration of photoinitiator is 5%. Under the optimum conditions, acrylic acid is successfully grafted onto the surface of polyester fabric. There are grafting polymer between the fiber gaps or on the surface of fiber, accompanied by cross-linking or bonding. The hydrophilicity and dyeing rate of modified polyester fabric are improved obviously. The breaking strength and elongation at break of treated polyester fabric increases and decreases, respectively.

Aiming at the selective adsorption treatment of ⁹⁰Sr in radioactive waste liquid, we need to synthesize MnO₂ and other inorganic ion exchanger with high selectivity for Sr²⁺ in the waste water, find the best material ratio, and prepare the raw material liquid. The feed liquid is blown into the hot dimethylsilicone oil by the self-made spherical particle preparation device and loaded on the Al₂O₃ matrix. The composite adsorbent with appearance and size similar to ion exchange resin was prepared. The physicochemical properties of the composite adsorbent were characterized by SEM,FT-IR and XRD.Different concentrations of strontium ion solution were prepared to study the change of adsorption capacity of Sr²⁺ at different time. The effects of pH on the adsorption properties of the adsorption properties under the influence of different initial concentrations and different coexisting ions were studied. According to the experimental data, the pseudo first order and quasi second order kinetic first order and quasi second order kinetic equations were used to fit the adsorption process. Two typical adsorption isotherm models, Langmuir and Freundlich models, were used to describe the adsorption process of Sr²⁺ by composite adsorbents.

Red Mud(RM), a kind of hazardous solid wastes produced during the process of alumina production, is disadvantageous for our environments owning to its characters of strong alkali and rich salt. It is essential to conduct innocent treatment. Summarizing the hazards of RM and methods of its comprehensive utilization, A reference for the deeper comprehensive utilization of RM in the future in this review was provided.

The results indicate that, when a battery is over-charged, the battery's surface temperature increases first because of ohmic heat, and after that, internal short-circuit occurs, resulting in the battery experiencing thermal runaway. However, in the case of over-discharge, the battery's surface temperature rise is limited. Therefore, during actual use, attention needs to be paid so as to prevent a battery from over-charge.

For 90~180°C low temperature waste heat resources, three different types of organic working fluids, benzene, isopentane and R245fa are selected from the perspectives of safety, environmental protection and physical properties of working fluid. The mathematical models of the system are established through MATLAB and REFPROP and the influence of the evaporation temperature on the performance of the ORC low temperature waste heat power generation system is studied. The results show that the thermal efficiency and net output power of the system increase with the increase of evaporation temperature; the evaporation pressure of CFC-type working fluids is relatively low; the net output power and thermal efficiency of HFC and HC-type working fluids are generally relatively low. The evaporator has the largest irreversible loss in the system, followed by the condenser and expander while the working fluid pump has the smallest irreversible loss.

To solve the problem of reinforcement bolt corrosion caused by the safe stability problem in geotechnical engineering, and engineering red line in geotechnical engineering, the fiber-reinforced composite material is gradually applied to the civil engineering field, and glass fiber reinforced polymer has high strength, light quality, corrosion resistance, the advantages of easy cutting has been widely used. In this paper, the stress distribution and deformation characteristics of GFRP anchors in the process of pipe pulling are studied through the excavation tube pulling test of GFRP anchors in actual working conditions. Secondly, the performance difference between the GFRP bolt and reinforced bolt in foundation pit engineering is analyzed. The results show that the axial force of the GFRP anchor bolt decays fastest near the anchor head, and decreases with the increase of anchor depth The shear stress distribution is convex. With the increase of the drawing load, the shear stress peak will increase, and the influence range of the shear stress will also increase. With the increase of the load, the shear stress peak of the GFRP bolt and the anchor solid will shift to the position far away from the anchor head.

The rapid development of the economy of China leads to the significant growth of energy production and consumption demand. At present, the total amount of greenhouse gas emissions has ranked second in the world. To meet the challenges caused by global climate change and environmental pollution as well as realize the sustainable development of our country's economy, carbon neutrality should be achieved. As a new type of low-temperature fuel cell, proton exchange membrane fuel cell (PEMFC) attracts a lot of attention due to its safe and environmentally friendly characteristics. However, the operating efficiency of the current commercial PEMFC is rather low (about 50%), which means that about half of the energy will be released as thermal energy. The stable and reliable heat dissipation of the fuel cell has a decisive impact on its performance and life, i.e., thermal management issues are particularly important for the efficiency and stability of the PEMFC stack. This article reviews the thermal management of PEMFC and analyzes the specific applicable conditions of cooling methods as well as the latest developments in thermal management methods. Specifically, it focuses on the thermal characteristics of PEMFC and its effects on performance and life. Besides, the PEMFC thermal management schemes and control strategies under different cooling methods are also summarized.

This paper makes a deep comparison and research on the cost of prefabricated concrete structure which is popularized vigorously by our country. By comparing the cost of three high-rise concrete residential projects with different prefabrication rates, this paper makes a detailed comparison of the total above-ground cost, civil construction and installation, and the cost of prefabricated components. On this basis analyzes the influence of adjusting prefabricated components on the prefabrication rate and the influence of prefabrication rate on the change of cost. Finally, it is discussed that the cost of prefabricated housing project is higher than that of traditional cast-in-place concrete housing mainly because of the increase of steel and concrete content of prefabricated components, transportation cost, main material consumption and comprehensive unit price. In this paper, the cost comparison and difference of prefabricated housing provides reference and reference for the future cost analysis of prefabricated housing.

Penstock pipe belongs to special pressure equipment, which has the risk of explosion. Therefore, it is necessary to strengthen the analysis of common accident damage forms and causes of penstock pipe, and do a good job in quality inspection to ensure the safe operation of penstock pipe. This paper mainly studies the penstock pipe of hydraulic storage power station. In the two kinds of steel, the more suitable steel structure is selected by semi elliptical crack analysis and FAD evaluation. According to the experimental data, steel B is more suitable for this structure. Because the failure time of the material, we make thickness correction with MATLAB. Finally, according to the analysis results, it is more appropriate to select steel B as the material of the penstock.

Aiming at the problems of low performance index and redundant information of multi-class physical health factors, a method of building rolling bearing health factors based on improved restricted Boltzmann machine is proposed. By fusing multi-class physical health factors, the virtual health factor of rolling bearings is constructed. Extracting physical health factors in time domain and frequency domain of rolling bearing vibration monitoring signals as inputs; the performance degradation mechanism model is added to the regularization term of the Restricted Boltzmann Machine, the performance degradation information contained in the input data is mined, the virtual health factor construction model of rolling bearings is built, and the model parameters are adjusted by the health factor evaluation criteria to improve the performance of the virtual health factor. The life cycle test of rolling bearings shows that compared with the principal component analysis method, the monotonicity of virtual health factors based on the improved restricted Boltzmann mechanism is increased by 147.6% and 38.5%, the trend is increased by 113.8% and 16.1%, and the robustness is increased by 60% and 8.42%, respectively.

Hydrophobic associating polymers show great potential in formulation of high-performance drilling fluids, due to their hydrophobic associative ability in high-temperature and high-salt conditions. Herein, a novel amphoteric polyacrylamide of poly(acrylamide/2-acrylamido-2-methyl-1-propanesulfonic acid/methylacrylethyl trimethylammonium chloride) hydrophobically modified with epoxidized soybean oil denoted as PAADE was prepared and applied in water-based drilling fluid, and one without hydrophobic modification (PAAD) was also used for comparison. Compared with PAAD, PAADE displayed characteristic association behavior with a critical association concentration (CAC) of 0.3 w/v%, and a salt thickening phenomenon over 3 w/v% NaCl concentration. The impacts of PAADE and PAAD on rheological and filtration properties of bentonite-based drilling fluid (BTDF) were evaluated under different salinity. The fitted Herschel-Bulkley rheological parameters indicated that BTDF containing PAADE showed stronger yield stress, easier flowability and better salt resistance at a reasonable concentration below CAC. Meanwhile, PAADE largely reduced the fluid loss of BTDF before and after thermal aging at 150°C, showing high temperature tolerance. The addition of NaCl promoted larger reduction of filtration. The superior properties of PAADE in BTDF were revealed to be the competitive results of salt-induced hydrophobic association and inter-particles configuration transition. Moreover, the incorporation of epoxidized soybean oil improved the biodegradability of PAADE.

A batch experiment was used to investigate the influence of common heavy metals Cr(VI), NI(II), Cu(II) on sulfur autotrophic short-cut denitrification. Experimental results show that low concentrations (1-3 mg/L) of heavy metals have little effect on sulfur autotrophic shortcut denitrification, and high concentrations (4-10 mg/L) of heavy metals have obvious effects on sulfur autotrophic short-cut denitrification. Inhibition. The doserape model is used to fit the doseeffect curve of heavy metals, and the IC₅₀ is used to judge the toxicity. The order of the IC₅₀ of each heavy metal is: Cr(VI)>NI(II)>Cu(II). The effects of two heavy metals in the binary system of Cu(II) and NI(II) are antagonistic.

Functionalized α-GDY with – H, – F, and – N for different displacement distance were designed as promising membranes for separation CO₂ from CH₄ by using molecular dynamics simulations. The α-GDY were regulated to form suitable pore sizes by functionalization and displacement for separation CO₂ from CH₄. F-GDY membranes and displacement distance with 1/3 have ultralow CO₂ selectivity over N₂ of ~0, which indicate that no CO₂ pass through F-GDY membranes and CO₂ and CH4 were separated efficiently. Among these membranes, N-GDY with 1/3 displacement distance has highest permeance of 5.97 × 10^-5 mol m^-2 s^-1 Pa^-1 at 300 K. Relative concentrations distribution confirmed that almost CO₂ molecules adsorbed the pore wall of membrane, CH₄ distributed in the gas box and vacuum. The interaction energy between gas molecules and membrane was analyzed to elucidate the significant impact of functionalization on the selectivity of CO₂ over CH₄ and CH₄ permeances passing through porous BN membranes.

In order to reveal the distribution characteristics of antibiotic resistance genes (ARGs) in freshwater aquaculture ponds, the microbial composition and antibiotic resistance gene types in the aquaculture environment were analyzed by using high-throughput and metagenomics sequencing technology. Our results showed that there were significant differences in the dominant bacteria composition in the water and sediment of aquaculture ponds. The dominant phylum in aquaculture water was Actinobacteria, Proteobacteria, Cyanobacteria and Bacteroidetes, while the phylum Actinobacteria, Chloroflexi and Proteobacteria were enriched in sediment. Compared with the comprehensive antibiotic research database (CARD), a total of 187 ARGs were identified, which were mainly multidrug, MLS and Tetracycline antibiotic resistance genes. There were 5 resistance mechanisms in the aquaculture environment, of which antibiotic efflux was the main resistance mechanism. Correlation analysis between ARGs and microbes showed that the abundance of Bacteroidetes, Cyanobacteria and Chloroflexi significantly affected the abundance of major resistance genes. This study is of great significance to protect the micro-environment of aquaculture ponds and control the pollution and spread of ARGs.

In the process of oil and gas development, the perfect reservoir damage evaluation method is an important condition to realize the economical and efficient development of the reservoir. At present, great progress has been made in the exploration of tight oil and gas. However, due to the characteristics of low porosity, low permeability and low water saturation of tight sandstone gas reservoirs, conventional reservoir damage evaluation methods are not applicable to it, and no systematic evaluation method has been formed yet. The damage evaluation methods of tight sandstone gas reservoirs mainly include the steady-state method and the unsteady-state method. The steady-state method is mainly the high temperature and high back pressure method, while the unsteady-state methods are the pressure attenuation method and the pressure transmission method which are widely applicable. Visualization technology, microfluidic technology, flow rate evaluation method and recovery evaluation method are the new methods to evaluate reservoir damage, which are in the further research. This paper summarizes the research progress of reservoir damage evaluation methods for tight sandstone gas reservoirs, analyzes the main evaluation methods, experimental equipment and improvement measures, and points out the problems that need to be paid attention to and solved, in order to provide reference for efficient and accurate evaluation of reservoir damage in tight sandstone gas reservoirs.

In this study, the relationship between pruning methods and endogenous hormone contents related to flower bud differentiation of Brigitta blueberries cultivated in Southwest China was studied. We performed the top pruning in June. The contents of endogenous hormones related to flower bud differentiation of blueberry were measured and analyzed. After top pruning, there was no significant change in the content of ethylene among the five endogenous hormones, but top pruning had a significant effect on the content of the other four hormones, which indicated that top pruning could affect flower bud differentiation by regulating the content of endogenous hormones.

The advanced persulfate oxidation technology has shown great potential in the efficient degradation of organic pollutants in water body, owing to its strong oxidation ability, easy operation and many other advantages. At present, the development of this technology focuses on the choice of activation mode of persulfate, and its essence lies in the cleavage of O-O bond in persulfate. Iron-based catalysts have been widely used in persulfate activation because of their advantages such as earth abundance, eco-friendliness and cost-effectiveness. In this paper, the methods and research progress of activating persulfate by iron-based materials (including nanometer zero-valent iron, common zero-valent iron, nanometer iron tetroxide) are reviewed. Finally, the existing problems and development direction of persulfate advanced oxidation technology in the current application are analyzed, in order to promote the development of related research work.

With the significant increase in the amount of natural uranium mining in various countries around the world, a large amount of waste rocks are piled up in the tailings pond. If the uranium-containing wastewater is not treated, it will bring serious environmental problems. After related experiments in the laboratory, it is measured that the adsorption rate of high-tech products-MOF-808 material to uranium ions can reach 97% (the optimal pH=7.0, and the optimal dosage is 0.2mg/L). It can be used as a good adsorption material. Based on the high-efficiency selective adsorption of this material to uranium, a set of equipment using MOF-808 was designed in this paper. This device adopts improved intermittent processing, high integration and automation level, and small floor space. According to the desorption characteristics of the material, a simple membrane cleaning method is designed to recover high-concentration uranium-containing cleaning liquid, which greatly reduces the amount of mud and can produce considerable economic benefits. In addition, cleaning and operation can be carried out at the same time, realizing continuous uranium-containing wastewater treatment, which meets the requirements of energy saving and emission reduction, and is beneficial to the construction of green mines.

As a color and antiseptic additive, nitrite has been widely added to meat products. The large amount of nitrite remaining in meat products will generate carcinogenic nitrosamines in the body after eating, so natural sources of nitrate-rich fermented vegetables Powder has certain potential as a substitute for nitrite. In this paper, fermented beet powder rich in nitrite as the research object, spectral characteristics were analyzed. The stability of its pigments under the conditions of temperature, time, pH, metal ions, oxidants and preservatives were studied. The results showed that the maximum absorption wavelength of fermented beet powder measured with an ultraviolet spectrophotometer was 538 nm. The conditions that most affect the content of betacyanins were temperature, pH, and metal ions.

The anionic, cationic and nonionic polyacrylamide samples, as well as four kinds of inorganic salt samples, including sodium sulfate, sodium chloride, sodium carbonate and ammonium sulfate, were respectively analyzed with Fourier transform infrared spectroscopy (FT-IR) to establish their standard reference infrared spectra, meanwhile the characteristic peaks are distinguished. At the same time, the polyacrylamide samples containing different concentration and different kinds of inorganic salts were respectively analyzed with FT-IR to establish their IR spectra. Then a method used for quality control of polyacrylamide products was established, which can be used to evaluate the purity of the products, determine the impurities and relevant contents preliminarily.

Although ceramic-based oxygen transport membranes (OTMs) have irreplaceable advantages over traditional oxygen production technologies, their oxygen permeability and stability need to be further improved. Based on the theoretical starting point of increasing the three-boundary reaction zone and reducing blocking effect, a set of new dual-phase membranes 75wt%Ce_0.8Sm_0.1Cu_0.1O_2-δ-25wt%-Sm_0.8Sr_0.2Co_0.8Fe_0.2O_3-δ (CSC-8282) and 75wt%Ce_0.8Sm_0.1Cu_0.1O_2-δ-25wt%Sm_0.3Sr_0.7Co_0.8Fe_0.2O_3-δ (CSC-3782) with different strontium contents were prepared by a one-pot sol-gel method ensuring that each element has the same chemical potential. The surface morphology, crystal structure and element distribution are systematically studied by SEM, XRD and EDS, which confirms that the synthesized membranes have an obvious dual-phase structure and excellent compactness. The results of the oxygen permeability experiment show that the oxygen permeability of CSC-3782 is always higher than that of CSC-8282 under any conditions due to the inducing effect of strontium on oxygen vacancies, and flow rate of CSC-3782 at 960°C reached 0.64 and 0.22mL⋅cm^-2⋅min^-1 for He and CO₂ as a sweep gas, respectively. The final long-term stability test confirmed that the dual-phase composite membrane with great prospects for development has high temperature stability and CO₂-tolerant property, and the doping of strontium to A-site of perovskite contributes to the improvement of its performance.

In order to study the rock thermal cracking law of the roof rock in the combustion zone of underground coal gasification under the special condition of unidirectional heating, the PFC particle flow software was used to carry out the numerical simulation of thermal-mechanical coupling. The uniaxial compression experiment was used to complete the PFC parameter calibration, establish a mechanical model, and compare the results of the unidirectional heating test with the simulation results. It was found that the relationship between the temperature at the measuring point, the thermal stress and the heating time of the two is very similar. It shows that the simulation results are highly accurate. The simulation results are as follows: when the model is at 450°C and 600°C, larger-scale cracks are formed and the second larger-scale crack evolution occurs; acoustic emission simulation can be divided into three stages: the first peak stage, the energy accumulation stage, and the second stage. In the second peak stage; the number of model cracks increases with the increase in temperature, and the shear cracks are the main ones, indicating that the model will expand laterally after being subjected to thermal stress, mainly occurring shear failure.

In this paper, the drop strength of pulverized coal in a hot air dense medium fluidized bed was studied, and the influence of factors such as coal surface moisture, drying temperature, drying time, air volume and other factors on the drop strength were investigated, and the mathematical correlation of the drop strength was established; it shows that with the increase of drying time, the fall intensity of coal decreases; as the drying temperature rises, the fall intensity decreases; as the surface moisture of coal increases, the coal fall intensity decreases; as the air volume increases, the coal fall intensity decreases.

In this paper, Box-Behnken response face model was used to establish the decomposition rate model of fungi. Based on the single factor simulation test data in the literature, this paper uses the Design-Expert 8, aiming at the peripheral range value of single factor optimization results, the orthogonal rotation combination experiment of multiple factors was designed to obtain the response surface regression model of fungi decomposition rate and temperature, time, quantity, population proportion and other factors, and to solve the optimal parameter combination; on the other hand, according to the research data of the title, taking the humidity tolerance as the link, the relationship function of fungi decomposition rate and growth rate, humidity tolerance was established by using MATLAB. Combining the two models, the decomposition rate model under the interaction of multiple fungi was established. The main factors affecting the decomposition rate of fungi were found from different angles by two methods, and different fungi were organically combined by growth rate and moisture resistance.

In order to explore the economic and comprehensive utilization of electrolytic manganese residue (EMR), the reaction kinetics of sodium carbonate roasting EMR were studied by using the model of flake structure minerals. The results showed that the initial roasting reaction was controlled by chemical reaction, while the middle and late reaction is controlled by diffusion. From the content of available silicon and the change node of the control type, the roasting reaction was basically completed in the initial stage. Therefore, chemical reaction control was the determining factor affecting the available silicon content in the process of sodium carbonate roasting EMR.

Two new combined technologies, reverse osmosis (RO) + electrodeionization (EDI) and reverse osmosis (RO) + ion exchange (IE), were studied for simultaneous desalination and boron removal of seawater. The results show that the RO system has excellent desalination performance under the experimental conditions, and can provide stable desalination rate for the subsequent processes of the two combined schemes. The boron concentration in water has little effect on the desalination rate of RO system, and the boron removal rate of RO system is between 47% and 50%, which provides a good early treatment for the subsequent process. The blank experiment shows that the salinity has little effect on the boron removal rate of RO-EDI equipment, and the boron removal rate is more than 93%, which has excellent and stable boron removal performance, but the water yield of RO-EDI equipment is low (less than 60%). The RO-IE system has a high water yield (> 70%), but the equipment has poor adaptability to influent boron concentration and salinity. The results of effluent water show that the boron concentration of raw water by RO-EDI combined process can be adapted to a wider range, and the influence of salinity is less. Considering comprehensively, RO-EDI process has more advantages and broad application prospects.

This paper studies the percentage of pulverized coal in the hot air dense medium fluidized bed, and investigates the influence of coal surface moisture, drying temperature, drying time, air volume and other factors on the percentage of crushing, and establishes a mathematical correlation formula for the percentage of crushing; it shows that with the increase of drying temperature, the percentage of crushing increases; with the increase of air volume, the percentage of crushing increases; the percentage of crushing increases with the increase of drying time and increases with the increase of surface moisture of coal.

Precipitation of harmful substances in the faucets has always been the focus of attention, this experiment selected the four metal elements of Pb/Cu/Ni/Mo as the research object, and studied the precipitation in the faucets which were extracted at the ambient temperature of 20°C, 40°C and 60°C. The results showed that the Pb and Mo precipitation in the faucets increased with the temperature rise, while the Cu and Ni in most samples were the least precipitated at 60°C. Detection found that the metals precipitation among different batches and different samples in the same batch varied widely, mainly affected by the processing technology and the material of faucets.

The aerobic granular sludge (AGS) process has been regarded as a promising sewage treatment technology. Compared with the activated sludge process, AGS process has the advantages of high efficiency and saving space. However, AGS process has several limitations in its application such as long cultivation cycle and easy disintegration. In this study, Fe²⁺ was added to the wastewater to cultivate AGS. The improvement on the cultivation of AGS with the addition of Fe²⁺ was investigated by analyzing the characteristics of AGS and the removal efficiency of pollutants. The results showed that adding Fe²⁺ (3~5 mg/L) to the reactor could effectively promote the formation of AGS. The sludge particles could be granulated within 7 days with the average particle size of more than 0.35 mm. In addition, the SEM showed that the dominant microorganisms were coryneform bacteria inside of the AGS. The XRD results indicates that the Fe²⁺ was converted into Fe2O3 presenting in AGS. The mixed liquid suspended solids (MLSS) and the sludge volume index at 30 min (SVI30) was 3.1 g/L and 40 mL/g, respectively, at the 40th day. The COD and NH₄⁺-N were effectively removed by AGS. This study could provide an effective approach for rapid formation of AGS.

MgO nanoparticles (MgO NPs) were obtained by a simple hydrothermal-calcination method. The influence of three different surfactants on the surface morphology, particle size and antibacterial performance of MgO NPs was investigated. The SEM results indicated that compared with using benzoic acid and citric acid, the MgO sample has more regular flake morphology and well dispersion, moreover, its particle size has more small and uniform when EDTA-2Na was used as the surfactant. The colony-forming unit count and optical density (OD) measurement results suggested that MgO NPs prepared using EDTA-2Na had the best antibacterial activity against Escherichia coli (E. coli), which might be originated from the small particle size and low aggregation. Our study demonstrated that using proper surfactant was a key way during the synthesis process to control the size and morphology of MgO NPs and enhance its antibacterial efficiency, and this way was expected to be applied to other inorganic antibacterial agents.

The ammonium salts and organic salts are the important components of atmospheric aerosols. The reaction between the two salts will cause the release of NH₃, hence, affecting the budget of NH₃ in the atmosphere. Furthermore, the equilibrium partitioning of NH₃ in the gas and particle phases plays a key role in the evolution of chemical composition and size of fine atmospheric particles. In this work, the chemical composition evolution processes of mixed particles consisting of four different organic acid salts (sodium oxalate (SO), sodium malonate (SM), sodium succinate (SS), sodium pyruvate (SP)) with ammonium nitrate (AN) were measured by attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR). The release of NH₃ were gained by monitoring the changes in the absorbance of NH₄⁺ in mixed organic acid salts/AN particles under 70% relative humidity (RH). After 127 minutes, the remaining ammonium content in the four mixed aerosols was 84.2%, 71.6%, 57.1%, and 28.7% for SO, SM, SS, and SP mixed with AN, respectively, which is lower than that in pure AN aerosol (97%). This study may help to further understand the conversion process between organic salts and AN in the atmosphere, as well as the NH₃ cycles in the atmosphere.

Here, we report a facile preparation of a low-platinum catalyst derived from ZIF-69 denoted as Pt@ZC-69. Nitrogen-abundant ZIF-69 could act as a support to efficiently encapsulate trimethyl (methylcyclopentadienyl) platinum (IV) (MeCpPtMe₃@ZIF-69) precursor. After high-temperature reduction, Pt@ZC-69 with uniform Pt-loading was obtained. In the acidic medium, the Pt@ZC-69 presented a desirable performance, the half-wave potential could reach 0.845 V vs. RHE, while the Pt content is less than 10% of the commercial 20 wt.% Pt/C. Moreover, Pt@ZC-69 also possessed robust stability (40 mV decays after 20000 cycles).

In this paper, chestnut flowers from the Huairou District of Beijing were used as experimental materials. It was aimed to explore the removal effect of nitrite by ethanol extract simulation system of chestnut flower and its impact on nitrite in food. The content of nitrite was measured by the naphthalene ethylenediamine hydrochloride method. In the experiment, the ethanol extract of chestnut flower was added when pickling vegetables. During pickling, adding the ethanol extract of chestnut flower could decrease the content of nitrite. As a consequence, the peak of nitrite was delayed one day due to the addition of 0.2 g/mL ethanol extracting from the chestnut flower.

We synthesized a novel phenanthroline-based mononuclear Fe(II) compound [Fe(TTD)₂(NCS)₂]⋅CH₃CN (1, TTD = 1,4,8,9-tetraaza-triphenylene-2,3-dicarbonitrile). And its crystal structure, optical and magnetic properties were analyzed. The thermally induced SCO of the compound is a one-step abrupt transition. In addition, light can also control the spin state of the compound. By using 660 nm light-excited compound, LIESST (light-induced excited spin-state trapping) effect can be achieved.

The composition of the berberine wastewater is complicated with high concentration of chemical oxygen demand (COD). Because it is hard to be degraded by traditional biochemical treatment and causes serious environmental pollution. The applicability of internal electrolysis to improve the biodegradability of berberine wastewater to be treated biologically was investigated. The wastewater was originated from a factory producing berberine. Treatability studies were conducted under laboratory conditions in order to determine the operational conditions to enhance the biodegradation of the wastewater.The major operational conditions, such as the initial pH, the second stage pH, the volume ratio of iron-carbon microelectrolysis filler to waste water and aeration time were investigated in the paper. The result of the experiment shows that the initial pH 2.0-2.5, second stage pH 9, the best volume ratio of iron-carbon micro-electrolysis packing and wastewater is 1:1 and the the residence time control in 120 minutes are the best operating parameters on the berberine wastewater treatment.

Pot experiment was carried out to study the chemical form of Pb and Cd in two plants under the condition of Cyperus glomeratus and Zea mays intercropping. The results showed that: (1) The chemical form of Pb in two plants are mainly F_NaCl and F_R. Compared with monoculture, Pb content of various chemical forms in C. glomeratus increased by 5.88%~300% under intercropping, and decreased by 5.69%~47.69% in Z. mays. (2) The chemical form of Cd in both plants are F_NaCl and F_HCl, the F_R Cd contents in the shoot of C. glomeratus increased by 21.45% and the F_W, F_HCl and F_R Cd contents increased by 12.06%~33.33% under intercropping system; the F_HCl Cd contents in the shoot of Z. mays decreased by 21.84% and the F_W, F_NaCl, F_HAC and F_R Cd contents in the root of Z. mays decreased by 12.96%~61.03% under intercropping system comparing with monoculture system. It is shown that intercropping of C. glomeralus and Z. mays affects the chemical form of Cd and Pb in plants, promoting the absorption and accumulation of Pb and Cd in C. glomeralus, and inhibiting the accumulation of in Z. mays.

The principle of infrared thermal imaging is briefly described. According to the actual situation of the boiler and the investment cost, the location and quantity of the infrared cameras are analyzed, it is reasonable to set up an infrared camera on both sides of the end of the boiler grate for combustion monitoring. In addition, the thermal image of coal combustion in the boiler furnace monitored by the infrared cameras are analyzed and researched. It is concluded that the infrared thermal imaging technology can be applied to the combustion monitoring of coal-fired boilers, which is beneficial to saving coal, energy saving and environmental protection.

The large-scale volume fracturing development of shale oil horizontal wells, and the production is affected by seasonal cycle and emergencies, resulting in the complexity of production prediction. Aiming at the problem of poor actual effect or heavy workload of shale oil production prediction by classical reservoir engineering, reservoir numerical simulation and other methods, a new shale oil production prediction method based on Prophet algorithm is proposed It is easier to find the inherent law from a small amount of data. In this paper, we use the production data of production wells in Huanjiang A reservoir in 2015 to predict the production, and compare the prediction results with long-term and short-term memory neural network (LSTM) and ARPS production decline model. The results show that the prediction accuracy of Prophet algorithm is higher, and it is more accurate for the production of complex shale oil.

In this study, two S⁰ particle packed reactors were constructed to explore the influence of alkalinity content on S⁰-based autotrophic denitrification (SAD) with nitrate and nitrite as electron acceptors respectively. As a result of the comparative experiment, when the alkalinity of influent is sufficient (HCO₃^-: NO₃^- mole ratio > 1.5:1), NO₃^--N and NO₂^--N reactor both showed high removal efficiency. But when the HCO₃^-: NO₃^- mole ratio decreased to 0.2:1, the average removal rate of NO₃^--N decreased to 31%, and NO₂^--N average removal rate still maintained at 95%. Based on the results, the reduction of alkalinity can significantly reduce the nitrate removal efficiency, but has little effect on the nitrite removal efficiency. This study further explained the characteristics of alkalinity consumption of the two stage of SAD and may provide a reference for future research.

To treat domestic sewage with high efficacy and low cost, the technology of shortcut simultaneous nitrogen removal was used with a new biofilm reactor. The influences on nitrogen removal effect by start-up procedure, nitrogen transformation characteristics and main factors (hydraulic retention time, dissolved oxygen, carbon-nitrogen ratio) were analyzed. The results indicate that: The reactor finished start-up of shortcut simultaneous nitrogen removal in 14 days of cultivation time after the biofilm cultured in the carrier. The ammonia nitrogen removal rate, simultaneous nitrification-denitrification rate and cumulative nitrite nitrogen rate respectively reached 91.3%, 82.7% and 63.4% in the last phase of start-up procedure. To remove ammonia nitrogen with the technology of shortcut simultaneous nitrogen removal efficiently and steadily, hydraulic retention time, dissolved oxygen, carbon-nitrogen ratio should be controlled in 3.56 hours, 1.5 mg/L and 5~8.

Noise pollution, which is no less harmful than air, water and soil pollution, is becoming an environmental shortcoming that cannot be ignored. Scientists are also seeking various solutions to work on reducing noise pollution. In this work, porous graphene aerogel (FD-GA) and porous graphene oxide aerogel (FD-GOA) prepared by foaming combined with freeze-drying are reported as acoustic-absorbing materials. The effects of thickness and degree of compression on the acoustic-absorbing performance of FD-GA and FD-GOA in the 1000-6000 Hz range, where human ear hearing is sensitive, were investigated, respectively. FD-GA was found to have significantly higher acoustic absorption performance with a peak absorption of 96.7%. The present work provides a simple and straightforward strategy for the synthesis of the acoustic-absorbing material. Key words: freeze-drying, graphene aerogel, acoustic-absorbing

Because mercury has the characteristics of volatility, toxicity and global migration, mercury pollution has become a hot, difficult and focus issue of global concern. Based on China's environmental technology verification method, the case study for low-temperature plasma integrated technology for the treatment mercury-containing exhaust gas in the treatment process of waste fluorescent lamps was carried out. The total gaseous mercury in the exhaust gas after treatment was less than 0.01mg/m³, which met the emission limit requirements in the Emission Standard (GB16297-1996). The pulse voltage of the plasma power supply is 10-35kV, the pulse current is 8-160A, and the pulse frequency is100-1000Hz. Case study showed that low temperature plasma integrated treatment technology is the available technology for advanced treatment of mercury-containing waste gas.

In this study, we constructed a H-rGO-Pt@Pd NPs with the characteristics of glucose oxidase. Then, the H-rGO-Pt@Pd NPs and Au NPs was modified on the surface of screen printed electrode to form an enzyme-free glucose biosensor. Among them, H-rGO-Pt@Pd NPs/Au NPs has a strong ability to capture electrons and catalyze the hydrolysis of glucose, resulting in a current-time change. The i-t curve is used to record the current-time change under different glucose concentration. When the glucose concentration was in the range of 0.6-1.4 mg/mL, the sensor current response value (Y) showed a linear relationship with the glucose concentration (X). The linear regression equation was Y=4.8515X-9.9361, the correlation coefficient was 0.9844, and the minimum detection limit was 0.2 mg/mL. In addition, the sensor has good specificity and stability.

Using core, mud logging and logging data, the study on the sedimentary characteristics of the Yan 6 oil layer of the Yan'an Formation in the X area of the Ordos Basin was carried out. It is believed that the Yan 6 oil layer in X area mainly develops delta deposits, and the subfacies is delta plain. The sedimentary microfacies are mainly diversion channels, inter-branch swamps and natural dikes. According to coring well data, sand body shape analysis, and logging facies analysis. Vertically, the sand bodies in the Yan 6 oil layer group are discontinuous, and there are mainly distributary channels and inter-branch swamps. Horizontally, the Yan 6 oil layer group develops 7 river channels, which are distributed in a strip on the plane, and the extension direction is northwest-south east. The comprehensive characterization of the sedimentary microfacies and the distribution of reservoir sand bodies in Yan 6 oil layer provides a reliable basis for the oil field to adjust the oil production plan in time.

A supported (nBuCp)₂ZrCl₂ metallocene catalyst was prepared and used in the slurry copolymerization of ethylene/octene-1 with triethylaluminium (TEAL) as co-catalyst. The effects of polymerization temperature on the properties of both the catalyst and resulted copolymers were investigated. The results show that the yield of supported metallocene catalyst reaches 4.3 kgPE/gcat and the bulk density of PE is higher than 0.4 g/cm³, the fines content of the polymer is less than 12.0 wt%, and the molecular weight distribution (MWD) of products ranges from 2.9 to 4.0 within the polymerization temperature range of 73~88 °C. These results are beneficial for large-scale industrialization of supported metallocene catalysts, and also provide a reference for academic research.

Acoustic stealt of the submarin has always been the most valuable research field for Security Department of the Navy over the world. In this paper, the feasibility of underwater anechoic coating with the polymer matrix piezoelectric composite material has been studied. On the basis of the Thomson-Haskell matrix method, we have derived the reflected transform matrix and calculated a semi-analytical solution to the problem by using the MATLAB. It is found that the underwater anechoic effects of this new material are related to the material proportion of each composites, the control voltage, geometric parameters, incident angle and frequency and so on. The studies have showed that: the polymer matrix piezoelectric composite material takes the advantages of both the viscoelastic material and the piezoelectric material and the use of the new material has a superior nature than the traditional materials to the suppression of underwater acoustic reflection.

The dual-carbon nanomaterial graphene has attracted the attention of scientific researchers all over the world because of its excellent properties and structure. Among them, graphene as anode material for lithium battery is a hot topic. In this study, the properties of graphene, the preparation method of graphene, the application prospect of modern graphene and the existing preparation methods are discussed.

As an electric energy conversion medium with economic value, hydrogen energy, which is storable and highly adapted to new energy, can be used as an energy storage medium to ensure the stable output of energy and the continuous running of vehicles in the context of the continuous deterioration of the global environment and the constant decline of the total amount of traditional fossil fuels. This paper summarized the development status of hydrogen fuel vehicles and development characteristics of corresponding technologies, and studied the technological development status of hydrogen fuel cell vehicles (HFCEVs) through the analysis of hydrogen energy for vehicles and through summaries of the development of hydrogen fuel vehicles and key technologies of hydrogen fuel cells.

As a widely used additive manufacturing (AM) technology, the selective laser melting (SLM) technology shows great potential for the sustainable development. Therefore, it is essential to conduct an accurate prediction of the AM energy consumption. In this paper, a new prediction method of SLM energy consumption is proposed. Through analysing the working states of each machine subsystem, this method established an energy consumption prediction model concerning the exposure time, point distance, laser power, and hatch spacing based on the characteristics of the pulse-laser-SLM machine. The model contributes to the improvement and optimization of the energy consumption prediction accuracy in the printing stage.

The online identification model parameters can reflect the real terminal voltage state of the battery in real time and provide accurate observation data for battery SOC estimation. BMS is an important part of new energy vehicles, which supervises and controls the working process of the battery. The core of BMS is SOC estimation, and the accuracy of its estimation is related to whether the battery works efficiently and safely. Based on Thevenin model, FFRLS-EKF and KF-EKF were used to estimate the SOC of ternary lithium battery under DST condition. The estimation results show that FFRLS-EKF has a maximum error of 0.0079, which can estimate the SOC of the battery well.

Lithium-ion batteries have been the most promising energy storage technology in the field of new energy due to their advantages such as high specific energy. With the further expansion of the application range, higher requirements are placed on the low-temperature performance of the battery. The development of suitable electrolyte additives to improve the interface structure of the electrode and the electrolyte is an effective and economically feasible method to improve the low-temperature performance of the battery. This article reviews the research progress of low-temperature electrolyte additives for lithium-ion batteries in recent years. It summarizes the action mechanism of low-temperature electrolyte additives from three aspects: organic solvent additives, lithium salt additives, and new additives. The development of low-temperature electrolyte additives in the next step was prospected.

In order to meet the weight reduction requirement of a tactical component, feasibility analysis by selected raw material, analyzing the stress and displacement under the working condition by finite element analysis method, a design of molding and curing are proposed. The results of feasibility by choosing suitable show that the mass of the composite component is reduced from 8.3Kg to 2.9Kg after optimization with the theoretical weight loss is 60%; the maximum stress is 50.9 MPa and the maximum displacement is 0.089mm; which meet the design requirement. The internal expansion pressure of the mold is designed as 1.0 MPa which meets the molding requirement. The design of this lightweight tactical composite component is clear, reasonable and feasible, which will have a certain guiding significance for the research of molding technology in related field.

Herein, a novel electrochemical immunosensor was fabricated based on copper oxide-reduction graphene oxide (CuO-rGO) nanocomposites for Glypican-3 (GPC3) detection. Firstly, CuO-rGO nanocomposite as nanoenzyme with good peroxidase-like properties is synthesized by One-step hydrothermal. Then CuO-rGO nanoenzyme captures GPC3 aptamer to form a signal probe, finally GPC3 antibody is used as the recognition probe to form an "antibody-antigen-aptamer" sandwich structure. Due to the peroxidase-like properties of the probe, this sandwich structure can effectively catalyze the reaction between hydrogen peroxide (H₂O₂) and silver nitrate (AgNO₃) and AgNPs is deposited on the surface of the electrode to amplify the final measured current. The Differential Pulse Voltammetry (DPV) method was employed to record the response signal of the immunosensor. The current response presented a linear relationship to the GPC3 concentration in the range of 1 to 40 μg/mL with the detection limit of 0.45 μg/mL.

A composite gel system was developed to solve the problems of low gel forming viscosity, gel forming and high salinity resistance in pH range of 6~8. The viscosity of the gel was determined by rotary viscometer, and the performance of the composite gel was analyzed. The pH of the composite gel, the gelation property of the mineralized degree and the plugging test of the sand filling pipe and the oil displacement experiment were carried out. The results showed that the gel performance of the composite gel was better than that of the conventional gel system at 60 degrees Celsius. The viscosity of the composite gel reached 10000 mPa S, at 0.1% polyacrylamide concentration, the gel forming range of pH was 6~12, and the viscosity of 20000 mg/L NaCl solution reached 15000 mPa/s, which had better salt resistance. The plugging test of sand filling pipe showed that the plugging rate of the gel to permeation layer was close to 90%, and the plugging ability was better. After 18% 0.2pv injection, the recovery rate increased by about 18%, which can meet the requirements of profile control in most oilfields.

Fuel sulfur content of marine sailing within the emission control area should not exceed 0.5%. Traditional boarding inspections are difficult, inefficient, and poorly targeted. Remote monitoring of air pollutants from ships is required to screen unqualified ships. The article investigates the topographical conditions and weather conditions of Tianjin Port, selects the technology of existing monitoring methods, elaborates and analyzes the composition and working principle of the current monitoring system, and finally forms a monitoring method of fuel sulfur content of ships in Tianjin Port.

Aiming at the properties of carbon materials, this article synthesized porous carbon nanorod materials by cellulose template method and characterized them by various analysis methods. The results show that these porous carbon nanorod materials have unique morphology and excellent electrochemical performance. It can be seen that these porous carbon nanorod materials have potential application value in capacitors.

The contents of Cr, Ni, Cu, Zn, As, Pb and Cd in standard soil for composition (GBW07403) and two soil samples were determined by XRF and ICP-MS, respectively. The results showed that XRF had higher precision than ICP-MS in the determination of seven metals in standard soil, but the relative errors of Ni, As and Cd were larger, up to -33%~22.7%. XRF and ICP-MS were used to determine contents of seven kinds of heavy metals in 2 soil samples, respectively. Both methods had high precision. F test showed that there was no significant difference in precision between the two methods except for Cd in No.2 soil. The t test showed that there were significant differences by the two methods for the determination of other heavy metals except for Cd and Cu (P ≤0.05). Although the method of XRF was fast and simple, its accuracy and comparison with other experimental methods need to be further studied due to the sample matrix effect.

This study proposed a multi-stage dual swirl burner for heating furnaces to achieve low nitrogen oxide (NOx) emissions based on swirling combustion and staging combustion technology. The effect of excess air coefficient on combustion characteristics and NOx emissions was studied by numerical simulation. The flow field, temperature field, oxygen concentration, and the NOx concentration distributions of the burner were discussed and analysed in detail. The simulated results showed that two recirculation zones for entrained flue gas formed in the reaction process by swirl blades. Meanwhile, increasing the excess air coefficient can improve the fuel/air mixing rate and diffusion effect in the combustion chamber, reducing the maximum combustion temperature and NOx emissions. Furthermore, when the excess air coefficient increased from 1.1 to 1.4, the maximum flame temperature was reduced from 1918.3 K to 1819.6 K, and the mole fraction of NOx at the outlet decreased from 1.67×10^-6 to 0.77×10^-6, which revealed the potential of the burner for the clean combustion.

H₂S is an endogenous gaseous signal molecule with cell protective function, which plays a critical part in many physiological and pathological processes. On the one hand, abnormal fluctuations of the concentration of hydrogen sulfide in the human body are closely related to diseases such as Down's syndrome, Alzheimer's, diabetes and cirrhosis of the liver. On the other hand, acts as an antioxidant in the body, hydrogen sulfide can protect cells from damage caused by reactive oxygen species. Therefore, it is indispensible to detect hydrogen sulfide in living organisms. A fluorescent probe—NX-H₂S, was constructed using azide group as the recognition group and naphthalimide as the framework. The spectroscopic properties of the probe were explored comprehensively. The experiment results show that NX-H₂S exhibits not only a fast response (5 min) but also excellent sensitivity and selectivity toward H₂S. In addition to the rapid detection of H₂S in vitro, NX-H₂S can also be successfully applied to the fluorescence imaging analysis of endogenous and exogenous H₂S in living cells.

The new multi-functional heat preservation cup can not only achieve long-term heat preservation, but also keep the water temperature at a more suitable temperature for drinking in a short time. It uses paraffin phase change heat storage material as the filler of the inner liner sandwich, which can absorb the heat in the water temperature and achieve rapid cooling; solar panels are used above the cup cover to supply power for electronic devices, which can save energy and protect the environment and avoid the trouble of charging back and forth; At the same time, a variety of electronic devices are added to the cup cover to enrich the customer's experience.

In order to investigate the dynamic characteristics of I-shaped novel simply-supported beams with the upper flange of rectangular high-strength concrete filled steel tube (RHCFST), the modal analysis of 16 simply-supported beams is conducted by ANSYS finite element software. The first order frequencies of the specimen beams are obtained in the Y direction. Based on the concentrated mass method, the frequencies of the specimens are theoretically calculated. By comparison the maximum error of the first-order frequency is 3.80%, which is in good agreement and can meet the precise requirements of practical engineering. The result shows that the first three order vibration modes of the specimen are consistent with the theoretical vibration modes. For the first-order vibration mode, the proportion of the effective mass to the total mass of the specimen is 79.2 % in the Y direction. Therefore, the first-order vibration mode in Y direction should be mainly taken into consideration for this type of beams during the structural design.

The widespread research for lithium metal anodes (LMA) has been rapidly developed in recent years. However, undesirable dendritic structures generated in the process of unstable lithium (Li) deposition dramatically restricts the cycle life of LMA. The skeleton structure of the three-dimensional (3D) host substrates are the potential promising host for Li, which can alleviate volume expansion during cycling. Herein, we propose a facile surface modification approach through ion sputtering, which can effectively regulate the lithiophilic properties of Cu foam (CF) for facilitating Li deposition. Au modified surface can enhance the lithiophilic property of substrates and induce uniform Li deposition along the conductive skeleton. Further analysis of results, substrate with Au coating modified surface exhibits a smaller Li nucleation overpotential (12 mV), a more stable coulombic efficiency (CE) at different current densities, and more uniform morphology of Li deposition with dendrite-free at large capacity of 4 mAh cm^-2. Meanwhile, symmetric cells with Au coating on CF can stably operate more lifespan than other samples. Furthermore, full cells paired with LiFePO4 cathodes and CF coated Au exhibit remarkable discharge capacities and capacity retention than others. This work provides new insights toward developing excellent 3D skeleton with modified surface for dendrite-free LMA.

Comparative trace copper and iron analysis of unused and running transformer oil is performed by iCP-MS with pretreatment by ashing, acid dissolution and direct injection method. The advantages and drawbacks of each of the listed methods are discussed. The direct injection method is so simple and time-consuming that can realize accurate determination of copper in oil, while it is not suitable for determination of iron in used transformer oil. Although limited by availability of equipment, acid dissolution method has good accuracy and reproducibility for the determination of transformer oil in all states.

In this work, poly(p-phenylene terephthalamide)(PPTA) fiber was modified by catechol and tetraethylenepentamine through Michael addition and Schiff base reaction. Then the silver-coated PPTA fiber was prepared by electroless plating. The SEM images showed that the phenolic hydroxyl group of catechol has a strong adhesion effect and a metal binding ability, which can make the silver particles tightly coated on the surface of PPTA fiber. The XPS and XRD results indicate that the Ag on the surface of the PPTA fiber is elemental silver, and there is no diffraction peaks of silver halide and silver oxide. The resistivity of the silver-coated PPTA fiber prepared with the deposition time of 2h has reached 0.1m^cm. This highly conductive PPTA/Ag fiber can be used in the field of flexible conductive materials and electromagnetic shielding clothing.

At present, the high voltage bushing composite insulator is widely used in AC/DC system substation, and its structural parameters show the nonlinear growth trend with the increase of voltage level. Therefore, in 1000kV UHVAC and 800kV UHVDC system, bushing composite insulator has the typical characteristics of long insulation distance and large radial diameter. At present, with the proposal of high-voltage power equipment compact optimization design scheme, the radial diameter of the composite insulator for bushing can be effectively reduced by reasonable design of internal capacitor core or metal shield structure optimization design scheme, so as to realize its large aspect ratio compact design. On the other hand, the insulation distance of high voltage bushing composite insulator will be further increased when it is applied in high altitude area. The innovation of this paper is how to carry out flashover voltage test to fill the current test data gap. In view of this, this paper first establishes two typical structures of the high voltage bushing composite insulators, including the three-dimensional finite element models of the composite insulators for capacitive core converter transformer bushing and the double-layer metal shield through the wall bushing, obtains the distribution characteristics of typical voltage and electric field under the operating state, and analyzes the local high field strength and corona, the electric field distribution of composite insulators for bushing. Furthermore, the actual flashover tests between large fittings air metal grounding body and large fittings composite insulator metal grounding body are carried out in the laboratory environment, and the quantitative relationship curve between flashover voltage and space net distance is obtained. Based on the above theoretical analysis and test data, the size altitude correction and umbrella skirt contour topology optimization of composite insulator for the UHV AC/DC bushing are carried out. Finally, the DC withstand voltage test and one minute power frequency withstand voltage test are passed, which proves the rationality and effectiveness of the design of composite insulator for bushing at UHV level. In this paper, starting from the typical electric field distribution characteristics of all kinds of composite insulators for bushing, the flashover law is studied for the first time, and the flashover test is carried out in the laboratory to supplement the classical test data. The research results have good theoretical and practical significance for installation, design and operation maintenance of all kinds of composite insulators.