The need for lithium-ion batteries with high energy density and long cycle life is becoming more and more urgent. This is because electric vehicles and large-scale energy storage systems are expanding at a rapid speed. Among all the possible positive electrode materials, ternary layered oxides (LiNixCoyMnzO₂, or NCM) are seen as a key material system for next-generation high-energy batteries because of their high specific capacity and relatively low cost. But there are some challenges that stand in the way of their real application, such as complicated synthesis processes, unstable structure in high-nickel compositions and serious side reactions at the material interface. This paper gives a detailed and systematic review of the latest progress in the creative synthesis methods and performance optimization ways for NCM positive electrode materials. It also talks about the main preparation methods, including the sol-gel method, coprecipitation and hydrothermal synthesis. The paper sums up the newest development of these techniques, with a focus on making synthesis processes simpler, making materials more homogeneous, controlling the microstructure well and making the electrochemical performance better. In short, new ideas and changes in synthesis routes can make the elemental uniformity, structural integrity and electrochemical stability of NCM materials much better, and in this way, they provide reliable material solutions for the development of high-performance lithium-ion batteries.

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Heavy oil is very thick and flows badly. So it is hard to get heavy oil from the ground. This paper uses ultrasound to make heavy oil less thick. First, this paper studies how ultrasound works. Ultrasound can break the material inside heavy oil. Then, this paper uses COMSOL to build a model. It studies how frequency and voltage affect the sound field in heavy oil. The study shows that the best effect is at 20kHz. Sound pressure becomes higher when voltage is higher. Using right frequency and higher voltage can make ultrasound work better. This gives help for making better ultrasound equipment.

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Calcium looping (CaL) is a great way to store thermal energy because it holds a lot of energy. But there is a big problem: CaO adsorbents quickly lose their activity. When they get hot, they sinter. Also, the product layer blocks diffusion. Because of these issues, we cannot easily use CaL on a large scale right now. To fix this, researchers are adding oxygen vacancies at the atomic level. This paper reviews how oxygen vacancies change CaO-based materials for the better. First, we look at how people make these vacancies in the lab. For example, they use aliovalent doping or change the material's shape. We also list the main tools used to check them. Next, the paper explains the science behind this using Density Functional Theory (DFT) calculations. These calculations show us exactly how the vacancies work. They give ions an easier path to travel, which speeds up the physical movement (better kinetics). At the same time, the vacancies act as Lewis basic sites. They grab CO₂ molecules tighter, which helps the reaction happen (better thermodynamics). Finally, we talk about the remaining hurdles, especially keeping the materials stable at very high heat. We suggest that future work should combine live testing (in-situ) with data-driven computer models to build much stronger energy storage materials.

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Stance expressions and markers are a heated topic in global linguistic research, with style stance adverbs as a core form of stance markers, classified alongside epistemic and attitude stance adverbs. This study employs an AI-powered corpus-based comparative analysis method to probe into 11 top English style stance adverbs in the Chinese Learners of English Corpus, British National Corpus and Corpus of Contemporary American English. AI instruments are applied to optimize corpus data retrieval, statistical analysis and positional distribution mapping and make comparative analyses of their use characteristics and positional distribution of the style stance adverbs between Chinese English learners and native speakers to probe into their interpersonal pragmatic functions and use characteristics. The research findings reveal significant discrepancies: Chinese learners overuse style stance adverbs with a narrow vocabulary range, and misapply spoken-language positional conventions (initial/final placement) in written discourse resulting from insufficient understanding of their structural and functional features in academic contexts. This study deeps and widens stance adverb research and provides guidance for EFL teaching and learners' pragmatic competence improvement.

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