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To solve the problem of low efficiency of engineering archives management in the general environment, this paper researches vectorized engineering archives management mode. Firstly, the composition of the archive management system is introduced, the basic system is established according to the cyclic management process of engineering archives, and the vectorization technology and characteristics are explained. Subsequently, the traditional vectorization algorithm based on edge structure extraction is used as an example, and further vectorization calculation is carried out using the bilateral filtering model, weighted least squares method, Lo gradient minimization model, Snake parameter activity contour model, geometric activity contour model, and aggregation algorithm. The advantages of vectorization techniques in information extraction are exploited to provide necessary assistance to the actual archive management work. The results show that the images processed by vectorization have the lowest compression rate, with an average compression rate of 55.67%; among the three methods, the image storage space and compression time under vectorization technology are the smallest at about 324MB and 3.4s; and the method in this paper has the highest output signal-to-noise ratio and the lowest mean square error, which well preserves the shape of the signal time domain waveform and has better noise reduction performance.

Flexible pressure sensors are valuable in applications such as electronic skin, smart robots, artificial prosthetics, and wearable electronics. In this study, a fully packaged, flexible, self‐powered, long‐term stable sensor array based on piezoelectrets is developed for pressure monitoring. A pressure sensor with a microcavity structure and a thickness of 500 µm achieved an impressive piezoelectric coefficient of 23.8 pC N−1 and a fast response time of 93 ms. The sensor yielded an output voltage of 0.26 V when subjected to a force using 0.3 g soybeans, and it displayed a remarkable linear relationship (R2 = 0.992) between force and electricity with pressure ranging from 1.4 to 13.6 N and a sensitivity of 9 mV N−1. Real‐time monitoring of sound vibration, radial artery pulse, and finger movement is demonstrated along with the successful recording of dynamic pressure changes within the porcine knee joint. It holds potential for fields such as monitoring pressure changes in the movement of human bodies and robotics and can contribute significantly to pressure assessment during total knee replacement. [ABSTRACT FROM AUTHOR]

Aiming at the problems of the large storage, complex composition, low comprehensive utilization rate, and high environmental impact of coal gangue, this paper carried out experimental research on the preparation of iron oxide red from high-iron gangue by calcination activation, acid leaching, extraction, and the hydrothermal synthesis of coal gangue. The experimental results show that when the calcination temperature of coal gangue is 500 °C, the calcination time is 1.5 h, the optimal concentration of iron removal is 6 mol/L, the acid leaching temperature is 80 °C, the acid leaching time is 1 h, and the liquid——solid mass ratio is 4:1; the iron dissolution rate can reach 87.64%. A solvent extraction method (TBP-SK–hydrochloric acid system) was used to extract the leachate, and a solution with iron content up to 99.21% was obtained. By controlling the optimum hydrothermal conditions (pH = 9, temperature 170 °C, reaction time 5 h), high-purity iron oxide red product can be prepared; the yield is 80.07%. The red iron oxide was characterized by XRD, SEM-EDS, particle-size analysis, and ICP-OES. The results show that the red iron oxide peak has a cubic microstructure, an average particle size of 167.16 μm, and a purity of 99.16%. The quality of the prepared iron oxide red product meets the requirement of 98.5% of the "YHT4 Iron oxide Standard for ferrite". It can be used as a raw material to produce high-performance soft magnetic ferrite. In summary, this experimental study on the preparation of iron oxide red from coal gangue is of great significance for the comprehensive utilization of coal gangue to realize the sustainable development of the environment and economy. [ABSTRACT FROM AUTHOR]

Ultraviolet (UV) photodetectors have attracted extensive attention in various applications, including aerospace, optical communication, and fire warning. However, the intrinsic coupling of high responsivity and fast response as well as imperfect interface transmission impede the further improvement of UV photodetector. Here, a high‐performance Au‐decorated PbI2/ZnO pn junction UV photodetector with a one‐dimensional (1D) and two‐dimensional (2D) interspersed structure is presented. The pyro‐phototronic effect and energy band engineering effect from the localized pn junction generated by the layered p‐type PbI2 nanosheets along the c‐axis of ZnO are coupled to modulate the separation and transport of photogenerated carriers. Furthermore, the localized surface plasmon resonance of Au nanoparticles produces transient thermal power to raise temperature fast to enhance pyroelectric current. The self‐powered Au@PbI2/ZnO photodetector displays a high responsivity of 0.21 A W−1, excellent detectivity of 7.9 × 1012 Jones, and fast response/recovery time of 25/31 ms, under the illumination of 325 nm light with the power density of 0.08 µW cm−2. This work offers an effective strategy for designing high‐performance next‐generation optoelectronic devices. [ABSTRACT FROM AUTHOR]

The aluminum hydroxide produced by the Bayer process contains a large amount of water which leads to the consumption of a large amount of heat for moisture removal in the calcination process, resulting in an increased energy consumption. The effects of temperature and microwave power on the dehydration ratio and the dry matter ratio of aluminum hydroxide were investigated. The characteristics of temperature variation during drying were discussed. X-ray diffraction (XRD), scanning electron microscopy (SEM), laser particle size, Fourier transform infrared (FTIR) spectroscopy, and dielectric property analyses were made to characterize the dried materials. The analysis results showed that within the range of bench-scale experimental parameters, the dehydration ratio was higher and the proportion of dry matter was lower at a higher final temperature. Within the range of pilot-scale experimental parameters, the dehydration ratio increased with the increasing microwave power from 500 W to 1500 W. XRD spectra revealed that when the final temperature exceeded 220 °C, a part of the aluminum hydroxide underwent a low-temperature phase transition to boehmite. The SEM images and a particle size analysis showed that there was no significant difference between the morphologies of the powder obtained by microwave drying and conventional drying methods. The powder obtained by both processes had an average particle size of around 80 μm. The dielectric constant and the dielectric loss of the dried material decreased greatly. [ABSTRACT FROM AUTHOR]

Zinc oxide dust (ZOD) is an industrial solid waste produced in the production process of wet smelting Zn, with large output and great pollution to the environment. The recycling of metallurgical solid waste such as zinc oxide dust is very important to achieve the sustainable development of the circular economy. An experimental study of zinc (Zn) leaching from zinc oxide dust using an ultrasound-enhanced ammonia–ammonium chloride system was performed. The effects of ultrasonic power, leaching time, total ammonia concentration, and other factors on the leaching rate of zinc from zinc oxide dust were investigated. The results revealed that the leaching rate of Zn reached up to 80.70% under the condition of ultrasound power of 1000 W, reaction time of 15 min, total ammonia concentration of 6 mol/L, [NH3]:[NH4+] of 1:1, L/S of 5:1, temperature of 45 °C, and stirring speed of 100 r/min. The conventional leaching was conducted under similar conditions, except that the time was controlled to 40 min and the zinc leaching rate was 71.15%. The leaching rate of Zn in the ultrasound condition was improved by 9.55% compared with that in the conventional leaching process. XRD, laser particle size, and SEM-EDS analyses were conducted to study the leaching residues of ZOD. The analysis results showed that in the ultrasound condition, the largest leaching rate of soluble ZnO phases was achieved after 15 min of leaching. Under the ammoniacal system, it was difficult to leach ZnFe2O4, Zn2SiO4, and ZnS phases, which partly accounted for the low zinc leaching rate. Additionally, through ultrasound-enhanced treatment, the ZnO particles encapsulated in ZOD particles were broken into smaller sizes and exposed to the leaching solution. Thus, the leaching rate of Zn was improved. The experimental results show that ultrasound can tremendously improve the effect of Zn extraction from ZOD, shorten reaction time, and help reduce energy consumption and environmental pollution, making it a promising application in the treatment of secondary Zn resources. [ABSTRACT FROM AUTHOR]