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1.
Phonetica ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38869142

RESUMO

Connected speech processes (CSPs) occur randomly in everyday conversations of native speakers; however, such phonological variations can bring about challenges for non-native listeners. Looking at CSP literature, there seems to be very few studies that involved young foreign language learners. Therefore, the present study aimed to explore the development of connected speech perception skills by focusing on 201 9- to 12-year-old Chinese EFL children. It also incorporated systematic error analysis to further probe into the specific perceptual difficulties. The results indicate that: (1) Despite a significantly ascending trend for the overall growth of perception skills, no significant differences were found between 11 and 12 year olds in elision and contraction, which suggests that the developmental trend varied depending on different CSP types; (2) Although random errors decreased with age, the number of lexicon and syntax errors gradually increased, and the distribution of perceptual errors shifted from the level of words and syllables to that of phonemes; (3) The primary types of errors resulting in the perception difficulties for elision and contraction were consonant errors, grammatical errors and morphology errors. Ergo, this study enhances the understanding of connected speech perception among EFL children and provides some implications for EFL/ESL listening instructions.

2.
Adv Colloid Interface Sci ; 323: 103055, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38091691

RESUMO

The detrimental impact of corrosion on metallic materials remains a pressing concern across industries. Recently, intelligent anti-corrosive coatings for safeguarding metal infrastructures have garnered significant interest. These coatings are equipped with micro/nano carriers that store corrosion inhibitors and release them when triggered by external stimuli. These advanced coatings have the capability to elevate the electrochemical impedance values of steel by 2-3 orders of magnitude compared to the blank coating. However, achieving intelligent, durable, and reliable anti-corrosive coatings requires careful consideration in the design of these micro/nano carriers. This review paper primarily focuses on investigating the corrosion inhibition mechanism of various nano/micro carriers/barriers and identifying the challenges associated with using them for achieving desired properties in anti-corrosive coatings. Furthermore, the fundamental aspects required for nano/micro carriers, including compatibility with the coating matrix, high specific surface area, stability in different environments, stimuli-responsive behavior, and facile synthesis were investigated. To achieve this aim, we explored the properties of micro/nanocarriers based on oxide nanoparticles, carbonaceous and two-dimensional (2D) nanomaterials. Finally, we reviewed recent literature on the application of state-of the art nanocarriers based on metal-organic frameworks (MOFs) and covalent-organic frameworks (COFs). We believe that the outcomes of this review paper offer valuable insights for researchers in selecting appropriate materials that can effectively enhance the corrosion resistance of coatings.

3.
ACS Omega ; 8(16): 14420-14429, 2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37125122

RESUMO

A comparative study between the leaching behavior of inhibitive ions from conventionally pigmented and smart (with encapsulated pigments) epoxy coatings has been conducted. Leaching of calcium phosphate as an inhibitive pigment from epoxy coatings was tested in 3.5 wt % NaCl solution. The results showed that pigment encapsulation contributed to a more uniform and stable coating microstructure based on the Scanning Electron Microscopy-Energy-Dispersive X-ray Spectroscopy (SEM-EDX) analysis and a higher leaching rate of the inhibitive pigment via the Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) analysis, thereby enhancing both the active corrosion protection and the barrier properties of the coating film. This was further verified by the Electrochemical Impedance Spectroscopy (EIS) measurements. After 7 days of immersion in 3.5 wt % NaCl solution, the coating resistance of the smart epoxy coating with mesoporous silica nanoparticle encapsulated calcium phosphate (MSN-CP3%) was 2 × 109 Ω·cm2 compared to 1.1 × 106 Ω·cm2 and 2.6 × 106 Ω·cm2 for the conventional epoxy coatings pigmented with 3 wt % and 5 wt % calcium phosphate (CP3% and CP5%), respectively.

4.
Front Psychol ; 13: 1056827, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36524166

RESUMO

Connected speech processing (CSP) is of great significance to individuals' language and cognitive development. It is particularly crucial not only for clinical detection and treatment of developmental disorders, but also for the Foreign/second language teaching instructions. However, given the importance of this field, there is a clear lack of systematic reviews that summarize the key findings of previous studies. To this end, through searching in the scientific databases PsycInfo, Scopus, PubMed, ERIC, Taylor and Francis, and Web of Science, the present study identified 128 core CSP articles with high reference values according to PRISMA guidance and the following results were obtained through quantitative analysis and qualitative comparative synthesis: (1) The number of studies on CSP published per year showed an upward trend; however, most focused on English language, whereas the studies on other languages were comparatively rare; (2) CSP was found to be affected by multiple factors, among which speech speed, semantics, word frequency, and phonological awareness were most frequently investigated; (3) the deficit in CSP capacity was widely recognized as a significant predictor and indicator of developmental disorders; (4) more studies were carried out on connected speech production than on perception; and (5) almost no longitudinal studies have ever been conducted among either native or non-native speakers. Therefore, future research is needed to explore the developmental trajectory of CSP skills of typically developing language learners and speakers with cognitive disorders over different periods of time. It is also necessary to deepen the understanding of the processing mechanism beyond their performance and the role played by phonological awareness and lexical representations in CSP.

5.
Dalton Trans ; 42(4): 1174-9, 2013 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-23111349

RESUMO

A bottom-up approach is presented here for morphology control of Ln-asparagine (Asn) coordination polymers (CPs) from the macro to nanoscopic regime by tuning solvent polarity based on the π* solvent polarity scale in polar solvent-water mixed solutions. By a simple hydrothermal treatment, large macroporous spheres with sizes up to millimeters were obtained in ethanol (π*: 0.54)-water mixtures, and their formation mechanism was proved to be particle aggregation together with a hollowing process based on Ostwald ripening. Other solvents with increasing polarity were also used, and submicrometer spheres as well as fine nanoparticles were prepared in acetone (π*: 0.71) and DMF (π*: 0.88), respectively. When dioxane (π*: 0.55) was used here, whose π* value is similar to ethanol, large macroporous spheres were also prepared. Furthermore, with Ce- and La-Asn CPs large spheres as precursors, after calcination, ceria and lanthana large spheres with hierarchical structures were fabricated, respectively. Considering that many growth media of CPs are single solvent systems, designing certain solvents mixtures and tuning their polarity would bring us new opportunities to achieve morphology and composition control of CPs materials.


Assuntos
Asparagina/química , Elementos da Série dos Lantanídeos/química , Polímeros/química , Solventes/química , Água/química , Etanol/química , Nanopartículas/química , Porosidade
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