A Flexible NO2 Gas Sensor Based on Single-Wall Carbon Nanotube Films Doped with a High Level of Nitrogen.

Carbon nanotubes (CNTs) are considered a promising candidate for the detection of toxic gases because of their high specific surface area and excellent electrical and mechanical properties. However, the detecting performance of CNT-based detectors needs to be improved because covalently bonded CNTs are usually chemically inert. We prepared a nitrogen-doped single-wall CNT (SWCNT) film by means of gas-phase fluorination followed by thermal annealing in NH3. The doped nitrogen content could be changed in the range of 2.9-9.9 at%. The N-doped SWCNT films were directly used to construct flexible and transparent gas sensors, which can work at a low voltage of 0.01 V. It was found that their NO2 detection performance was closely related to their nitrogen content. With an optimum nitrogen content of 9.8 at%, a flexible sensor had a detection limit of 500 ppb at room temperature with good cycling ability and stability during bending.

The similar eye movement dysfunction between major depressive disorder, bipolar depression and bipolar mania.

OBJECTIVE: To find eye movement characteristics in patients with affective disorders. METHOD: The demographic and clinical evaluation data of patients with major depressive disorder (MDD), bipolar disorder (BPD), and healthy control (HC) were collected. EyeLink 1000 eye tracker was used to collect eye movement data. Chi-squared test and independent sample t-test were used for demographics and clinical characteristics. The Mann-Whitney U-test was used to compare the eye movement variables among four groups, and the FDR method was used for multiple comparison correction. Pearson correlation analysis was used to analyse the relationship between clinical symptoms and eye movement variables. RESULTS: Patients with affective disorders showed smaller saccade amplitude under free-viewing task, more fixations and saccades, shorter fixation duration, longer saccade duration under fixation stability and smooth pursuit tasks (all, p < 0.05) when compared to HC, but there was no significant difference in all eye movement variables among patients in the three groups. Also, all eye movement variables under the three paradigms had no significant correlation with clinical scale scores. CONCLUSION: Patients with major depression, bipolar depression and bipolar mania share similar eye movement dysfunction under free-viewing, fixation stability and smooth pursuit tasks.