262 research outputs found
Robust Ni/WC superhydrophobic surfaces by electrodeposition
No full textSuperhydrophobic, water repellent surfaces have attracted much attention but poor surface mechanical properties have limited their wider practical application. Robust surfaces based on nickel-tungsten carbide composite coatings have been electrodeposited. The surfaces showed superhydrophobicity after being modified by stearic acid. The maximum contact angle of water was 164.3 degrees with a sliding angle close to zero degree. By controlling deposition conditions, versatile coatings have been produced and the effects of morphology on wettability are discussed. Coating texture has been analyzed by X-ray diffraction. The surfaces showed excellent abrasion resistance and water-repellence
Electroplating of non-fluorinated superhydrophobic Ni/WC/WS<sub>2</sub> composite coatings with high abrasive resistance
No full textWeak hierarchical rough structures on superhydrophobic surfaces hinder their practical industrial applications. This paper reports a strategy to fabricate robust nickel-based superhydrophobic coatings via the codeposition of nanosized WS2 and WC particles. The Ni/WC/WS2 composite coatings were synthesized on mild steel substrates by one-pot electroplating followed by the adsorption of stearic acid self-assembled monolayers to modify the surface wetting. The particle concentration in the bath was investigated and the maximum water contact angle of approx. 170° was achieved by optimizing the particle contained. Hardened by WC and lubricated by WS2 inclusions the superhydrophobic coatings showed remarkable abrasive resistance with a bearing capacity ≥10,000 mm abrasion length. The coatings also showed aerophilic behavior and good environmental stability over >6 months
Organic–Inorganic Composite Electrolytes Optimized with Fluoroethylene Carbonate Additive for Quasi-Solid-State Lithium-Metal Batteries
No full textComposite
solid electrolytes (CSEs) are considered crucial materials
for next-generation solid-state lithium batteries with high energy
density and reliable safety, and they make full use of the advantages
of both organic and inorganic solid-state electrolytes. However, few
CSEs have sufficiently high ionic conductivity at room temperature
for practical applications. Here, a traditional CSE consisting of
poly(ethylene oxide) (PEO) matrix and Li1.3Al0.3Ti1.7(PO4)3 (LATP) fillers was optimized
by introducing a fluoroethylene carbonate (FEC) additive, resulting
in an improved high ionic conductivity of 1.99 × 10–4 S cm–1 at 30 °C. The symmetric Li||Li cell
assembled with the optimized CSE exhibited a low overpotential and
a good cycling stability of more than 1500 h at room temperature.
Moreover, the Li||LiFePO4 battery with the optimized CSE
delivered a discharge capacity of 132 mAh g–1 at
0.2 C after 300 cycles at room temperature. Comparisons
between the LATP-containing CSE and control electrolytes indicated
that the enhanced ion conductivity of the former resulted from the
synergistic effect of LATP and FEC. Comprehensive characterizations
and DFT calculations suggest that with the presence of LATP, FEC additives
in the precursor could transform into some other species in the preparation
process of CSE. It is believed that these FEC-derived species improve
the ion conductivity of the CSEs. The results reported here may open
up new approaches to developing composite electrolytes with high ionic
conductivity at room temperature by introducing organic additives
in the precursor and converting them into species that facilitate
ion conduction in the CSE preparation process
Design and implementation of IELTS learning resources system based on the data crawler
No full textWith the increasing demand for studying abroad and standardized language proficiency tests, IELTS (International English Language Testing System) has become one of the most widely recognized English exams globally. However, IELTS learning resources are often scattered across various websites and platforms, leading to issues such as inefficient retrieval, inconsistent formats, and delayed updates. Therefore, it is necessary to build a centralized and automated resource management system to improve access efficiency and user experience.
This thesis presents the design and implementation of an IELTS learning resource management system based on web crawling technology. The system is developed using the Spring Boot framework for the backend and Thymeleaf as the template engine for server-side rendering. MySQL is used for data persistence. The web crawler module, implemented with the Jsoup library, extracts structured data such as titles, categories, URLs, and summaries from designated educational websites. The system supports key functions including module-based browsing, keyword search, pagination, administrator login authentication, resource management, and manual data collection triggering.
Starting from the analysis of system requirements, this thesis elaborates on the choice of technologies, overall architecture, functional module design, database modeling, and implementation. Functionality testing and interface validation demonstrate that the system runs stably with good user experience. In summary, this system realizes an integrated “collection–management–presentation” workflow, providing practical value for organizing and utilizing IELTS learning resources more effectively
Thermodynamics of Vacuum Chloride Volatilization of Ni, Co, Mn, Li, Al, and Cu in Spent Lithium−Ion Battery
No full textIn recent years the chlorination leaching separation process in the field of hydrometallurgy has been developed considerably. However, the development of the chlorination separation process in the field of pyrometallurgy has lagged. In this paper, the thermodynamics of vacuum chlorination volatilization of valuable metals Ni, Co, Mn, Li, Al, and Cu from spent lithium−ion batteries is investigated, and it is found that chlorination helps to achieve the trapping and separation of the singlet metals. With the help of Factsage 8.1, a theoretical map of the stable regions of valuable metal chlorides, the order of separation of each chloride at 10 Pa, and a discussion of the behavior of excess CuCl2 in the system at different temperatures were determined. This paper provides research ideas in the fields of selective separation of alloying elements in the carbothermal reduction products of waste lithium−ion batteries and one−step separation of valuable metals by carbothermal reduction
The application of E-learning in entrepreneurial education based on experiential learning
No full text- …
