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- Zhang, Qing, et al.
(författare)
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Andersson-Magnéli Phases TinO2n-1 : Recent Progress Inspired by Swedish Scientists
- 2021
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Ingår i: Zeitschrift für Anorganische und Allgemeines Chemie. - : Wiley. - 0044-2313 .- 1521-3749. ; 647:2-3, s. 126-133
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Tidskriftsartikel (refereegranskat)abstract
- Among homologous series of metal oxides, Andersson-Magneli phases TinO2n-1 (n=4-10) have attracted renewed scientific attention because of their behaviour in electrical conductivity and chemical/thermal stability. Various applications have also been reported for the phases with different values of n, or slightly reduced rutile (TiO2). The characteristic properties of these materials depend strongly on the compositional deviation from TiO2 and the way in which the structure accommodates the deviation. Thus, an urgent requirement is to overcome difficulties in characterizing such materials at atomic resolution. Here, we trace the discovery of the Andersson-Magneli phases, and report the application of recent developments in electron microscopy to reveal the relation, at the local level, between structural characteristics and electronic states, specifically for the materials TinO2n-1 with n=4-8. The electrical conductivity of Ti4O7 has been reported previously to show three clearly distinct states on decreasing temperature from 300 K. For this reason, we focus on Ti4O7 as a representative example of the TinO2n-1 phases and report structural characteristics at temperatures corresponding to each of the three different phases, focusing on the distribution of Ti3+ and Ti4+ cations from analysis of single-crystal XRD data. Electron diffraction experiments and electrical conductivity measurements are also reported.
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| 2. |
- Zhang, Qinghua, et al.
(författare)
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Quantitative assessments of retinal macular structure among rural-dwelling older adults in China : a population-based, cross-sectional, optical coherence tomography study
- 2024
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Ingår i: BMJ Open. - 2044-6055. ; 14:2
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Tidskriftsartikel (refereegranskat)abstract
- ObjectivesTo quantitatively assess and compare retinal macular structures of rural-dwelling older adults in China using two different optical coherence tomography (OCT) scanners and to examine their associations with demographic, lifestyle, clinical and ocular factors.Design, setting and participants This population-based, cross-sectional study included 971 participants (age ≥60 years) derived from the Multimodal Interventions to Delay Dementia and Disability in Rural China study. We collected data on demographics, lifestyle factors, clinical conditions (eg, cardiovascular disease (CVD)) and ocular factors (eg, visual acuity and spherical equivalent). We used two models of spectral-domain OCT to measure macular parameters in nine Early Treatment Diabetic Retinopathy Study subfields. Data were analysed using the multiple general linear models.Results Spectralis OCT demonstrated higher macular thickness but a lower macular volume than Primus 200 OCT (p<0.05). Nasal quadrant of the inner and outer subfields was the thickest, followed by superior quadrant. Adjusting for multiple potential confounding variables, older age was significantly correlated with lower average inner and outer macular thicknesses and overall macular volume. Men had higher macular parameters than women. The presence of CVD was correlated with lower central macular thickness (β=−6.83; 95% CI: −13.08 to −0.58; p=0.032). Middle school or above was associated with higher average inner macular thickness (β=7.85; 95% CI: 1.14 to 14.55; p=0.022) and higher spherical equivalent was correlated with lower average inner macular thickness (β=−1.78; 95% CI: −3.50 to −0.07; p=0.042).Conclusions Macular thickness and volume assessed by Spectralis and Primus 200 OCT scanners differ. Older age and female sex are associated with lower macular thickness and volume. Macular parameters are associated with education, CVD and spherical equivalent.Trial registeration number MIND-China study (ChiCTR1800017758).
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