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Asphalt pavement has been repeatedly subjected to vehicle loads during service. The probability and risk of water damage and asphalt deterioration of asphalt pavements is relatively higher in high temperature and rainy areas such as the Guangxi region of China. In this paper, the changes in rubbermodified asphalt and its mixtures under high temperature, water cycling, and ultraviolet light have been investigated. The coupled water-light-heat effects on asphalt pavements were simulated by developing a freeze-thaw cycle test protocol and a UV environment simulator. The high temperature performance of asphalt and asphalt mixtures before and after aging was compared and statistically analyzed by indoor tests of needle penetration, ductility, softening point, rutting factor and dynamic stability. Under water-light-heat coupling, rubberized asphalt showed a deeper degree of aging, accelerated conversion of asphalt to a highly elastic material, and an increased tendency to reduce flow capacity. The results showed decreasing dynamic stability of rubberized asphalt mixtures with decreasing needle penetration and ductility, increasing softening point, increasing rutting factor and decreasing phase angle. The effect of UV light on asphalt needle penetration was more significant, while the number of freeze-thaw cycles had a more pronounced effect on softening point.

A nano-composite coating was developed by adding nano-SiO2 to a home-made Waterborne fluorine-containing epoxy resin. The surface hydrophlicity of the coating was investigated by the contact angle with water. As the particle sizes of SiO2 changed from 7-18nm, the water contact angle of the films changed from 62.8° to 85.6°. The surface energy of the coating was calculated out through measuring the contact angles of the coating with water and 1-bromonaphthalene. The presence of SiO2 significantly enhanced the corrosion resistance of the composite coatings, which showed two times than that of the neat waterborne fluorine-containing epoxy coatings. And the thermos dynamic stability of the composite coatings has been significantly improved. When the silica content is 2.0%, the coating has the largest contact angle. Other performance of the coating was investigated in terms of their thickness, flexibility, pencil hardness, impact resistance.

Electrostatic sensor is the most important equipment in aero-engine exhaust electrostatic character research. By comparing a variety of sensor test programs, the coaxial speaker-like noncontact electrostatic sensor program is proposed. Numerical simulation analysis indicates the electric field distribution of electrostatic sensor, the influence principle of gap width, outer diameter, center diameter, angle and other factors on the sensor capacitance values which identify the key indicators of electrostatic sensor. The experiment test shows that the simulation analysis is in good agreement with the experimental results.

Since the industrial revolution, human dependence on fossil fuels has resulted in increasingly severe atmospheric carbon dioxide (CO2) emissions. Electrocatalytic CO2 RR has attracted much attention because of its many advantages, such as mild reaction conditions, controllable reaction rate, low cost and scalable electrolyzer.[7] More importantly, electrocatalytic CO2 RR can control the selective generation of target products by rationally adjusting the reaction potential, electrolyte and catalyst species. However, the CO2 molecular structure is stable, and obtaining the key CO2 -based anionic intermediate CO2– from activated CO2 molecules requires overcoming a huge energy barrier. Copper (Cu) catalysts are the only monometallic catalysts to date that can form two-carbon (C2) products, which establishes their special position in the field. However, the poor selectivity of Cu for a particular product has led to a wide distribution of reduction products, covering the range from carbon monoxide (CO), a reduction product at 2e-, to ethanol (C H25 OH), a reduction product at 12e-. Meanwhile, Cu catalysts are generally less stable, which can seriously affect their commercialization. Currently, in order to obtain highly selective C2+ products (mainly ethylene and ethanol), [16]this article reviews the various methods developed by different scholars in China and abroad to modify Cu catalysts. Finally, this article suggests ways to improve the performance of Cu-based catalysts to enhance the Faraday efficiency of the C2 product from the electroreduction of C02 and gives an outlook on the future direction of Cu-based catalysts.[19]

This paper introduces the technical routes and characteristics of four traditional adiponitrile production processes, including acrylonitrile dimerization method, butadiene method, adipic acid catalytic ammonification method and caprolactam method, were introduced and compared in terms of reaction principle, process, production cost and environmental protection. The production process with low cost, low energy consumption and good environmental benefits was found to provide reference for the production and development of adiponitrile in China.

Currently, lithium-ion batteries are widely used in advanced electronic devices and electric vehicles due to their low weight, high energy density and long service life. Therefore, the number of waste lithium batteries is also increasing, and it is very important to recover the valuable resources in them. This paper reviews some conventional means of recycling lithium-ion batteries and mentions future directions. The application and recycling of all-solid-state lithium batteries will help to solve the problem of waste lithium batteries.

In view of the power quality problems such as voltage fluctuation and transformer overload caused by large-scale access of electric heating equipment, the comprehensive evaluation index system and the evaluation method of the distribution network carrying capacity were proposed. Taking IEEE33 node system as an example, based on the tested node electricity load and thermal load demand, through the calculation of each evaluation index, influence of different electric heating modes on the distribution network carrying capacity was analysed and the rationality of the proposed evaluation method was verified. The results showed that using electric heat pump with thermal storage system for heating can reduce the peak voltage deviation, the network loss and further ensure the safe operation of power distribution network under the premise of satisfying the user’s thermal load demand and the stability of the distribution network.

This paper describes Preformed Particle Gel (PPG) treatments for in-depth fluid diversion in four injection wells located in the northern section of the Lamadian reservoir, Daqing oilfield, China, which is a sandstone reservoir with thick heterogeneous pay zones. Forty-six producers were connected to the four treated injectors with an average water cut of 95.4% before PPG treatments. A large volume (more than 1 000 m3) of PPG suspension with concentrations of 1900-2 500 mg/L and particle sizes of 0.06-3.0 mm was injected into each well, each injection spanning approximately four months. The injection PPG suspension volumes range from 11458 to 17625 m3 per well with a total of 56269 m3 (295680 lb of dried PPG) for the four wells, which indicated the existence of super-K zones or fractures in the formation. During PPG injection, real-time data, including injection pressure, injection rate and particle sizes, were monitored to tune our treatment design and to analyze the practical status of the mature reservoir. This paper reports detailed information for the four well treatments, including well candidate selection criteria, treatment design, real-time monitoring results during PPG injection and treatment results. Le présent article décrit les traitements à base de gel à particules préformées (GPP) pour la dérivation de fluide en profondeur dans quatre puits d’injection situés dans la partie nord du gisement de Lamandian, dans le champs pétrolifère de Daqing en Chine; il s’agit d’un gisement de grès présentant des couches productrices épaisses et hétérogènes. Quarante-six producteurs ont été raccordés aux quatre injecteurs traités avec une proportion d’eau moyenne de 95,4 % avant les traitements à base de GPP. Un important volume (plus de 1000 m3) de suspension de GPP présentant des concentrations de 1900 à 2 500 mg/L et des tailles de particule de 0,06 à 3,0 mm a été injecté dans chaque puits, chaque injection durant environ quatre mois. Les volumes d’injection de suspension de GPP vont de 11458 à 17 625 m3 par puits pour un total de 56 269 m3 (295 680 lb, soit environ 134118 kg, de matière sèche de GPP) pour les quatre puits, ce qui indique l’existence de zones à haute perméabilité (K) ou de fractures dans la formation. Lors de l’injection de GPP, des données en temps réel, y compris la pression d’injection, le taux d’injection et les tailles de particule, ont été contrôlées pour ajuster notre méthode de traitement aux conditions de ce réservoir mature. Cet article présente des informations détaillées sur les traitements des quatre puits, y compris les critères de sélection des puits, la méthode de traitement, les résultats du contrôle en temps réel lors de l’injection de GPP et les résultats des traitements.

Magnetic Nanoparticles (MNPs) possess significant potential across various sectors due to their versatility. However, specific MNP sizes are crucial for effective utilization. Traditional methods for synthesizing monodispersed MNPs are often expensive, complex, or environmentally harmful. This study proposes the effect of flow rate on the size segregation of MNPs using a continuous flow low gradient magnetic separator (CFLGMS). To produce MNPs that are monodispersed, firstly, MNPs undergo functionalization with the polyelectrolyte, poly (sodium 4-styrene sulfonate) (PSS), to enhance colloidal stability. Employing PSS molecules as splicing agents effectively inhibits MNP aggregation. To further enhance the monodispersity of MNPs, continuous flow is facilitated by configuring three separator columns in series, with permanent magnets (NdFeB) attached to the sides. As larger MNPs exhibit stronger magnetic field attraction, resulting in their capture by magnets first, followed by smaller MNPs, and finally the smallest ones. Consequently, MNPs captured in Column 1 possess the largest size, while those in Column 3 have the smallest size. Additionally, this paper investigates the impact of solution flowrate on size segregation efficiency. By varying the solution flow rate (10 mL/min, 15 mL/min, and 20 mL/min), it is found that the performance of the size segregation system is higher under the lower solution flowrate.

This paper introduced the principle of angle errors in tracking system. The demodulation was only related to signal envelop, and supported the phase calibration of radio star. And this paper which is combined with the commonly-used phase calibration methods, carried out the phase calibration of radio star and the satellite on the specific device, summarized the procedure of radio star for phase calibration and compared the accuracy of it. On the basis of analyzing the theory of phase calibration, the authors concluded the relationship between the parameter of phase calibration and the working frequency. Through utilizing the results of satellite phase calibration to verification and the results of phase calibration of radio star on full-band, and achieving the parameter of phase calibration without the calibration tower, it has a good engineering practice value.

The paper introduces the theory and application of Power Plant's primary frequency compensation(PFC) on the unit with the supercritical forced circulation boiler. First of all,the paper gives the typical parameters Setting and logic design of PFC. Then it explains some adverse factors which affect the PFC of the unit. With some problems in the operative process, the typical control strategy and some advices are given , which can improve PFC ability of Power Plant's PFC.