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In this work, we modified nylon 6 with liquid rubber by in-situ polymerization. The infrared analysis suggested that HDI urea diketone is successfully blocked by caprolactam after grafting on hydroxyl of HTPB, and the rubber-modified nylon copolymer is generated by the anionic polymerization. The impact section analysis indicated the rubber-modified nylon 6 resin exhibited an alpha crystal form.With an increase in the rubber content, nylon 6 was more likely to generate stable α crystal. Avrami equation was a good description of the non-isothermal crystallization kinetics of nylon-6 and rubber-modified nylon-6 resin. Moreover, it is found that the initial crystallization temperature of nylon-6 chain segment decreased due to the flexible rubber chain segment. n value of rubber-modified nylon-6 indicated that its growth was the coexistence of two-dimensional discoid and three-dimensional spherulite growth. Finally, the addition of the rubber accelerated the crystallization rate of nylon 6.

With the exploitation of rare earth elements (REE) in southern China, desertification has become a serious ecological problem in this region. To accurately understand the desertification process in mining areas and formulate targeted ecological restoration programs, taking the Lingbei mining area in Ganzhou City, Jiangxi Province as the study area, we explored desertification information extraction methods, desertification dynamics monitoring, and desertification drivers in REE mining areas using multisource data from 1986 to 2021. The results show that from the method of extracting desertification information, Random Forest is the prominent (83.33%), followed by Albedo–NDVI (Normalized Difference Vegetation Index) space (74.44%), and thirdly Linear Spectral Mixture Model (65.56%). From 1986 to 2021, the desertification land area in Lingbei mining areas first increased and then decreased, showing a reverse trend, but it has not recovered to the pre‐mining level. The government's ecological reclamation measures are the key factors for the restoration of desertification land. There are still 17.81 km2 areas that have not been restored, of which 2.16 km2 are at the level of severe desertification. Moderate desertification and light desertification have not been completely curbed, which needs continuous attention. Vegetation coverage has the highest explanatory power to the distribution of land desertification in mining areas, followed by land use classification, indicating that human activities have a great influence on the spatial differentiation of land desertification in mining areas, and it is necessary to pay attention to regional balanced and sustainable development in the future. [ABSTRACT FROM AUTHOR]

Tungsten disulfide nanosheets(WS2) and dandelion-like platinum–silver nanoparticles(PtAg NCs) were synthesized by hydrothermal method and seed-mediated growth approach, and a novel dopamine(DA) electrochemical sensor based on PtAg/WS2/GCE was developed and a new method for detecting DA was established. The investigation of scanning electron microscopy (SEM) and transmission electron microscopy(TEM) exhibited that dandelion-like PtAg NCs were successfully dispersed on the surface of WS2 nanosheets with the size about ~ 10 nm and the thickness of WS2 nanosheet could be estimated to be 3.1 ± 0.02 nm with a lattice constants of 0.6 ± 0.03 nm, X-ray diffraction(XRD) and X-ray photoelectron spectroscopy(XPS) patterns proved PtAg exists as alloy form and both were metallic phases. The electrochemical results revealed the obtained sensors possessed ideal electrocatalytic activity toward DA with a wide linear range of 0.6 μM to 1 mM(R2 = 0.9991), high sensitivity (348.8 μA·mM−1·cm−2), low detection limit 0.2 μM (S/R = 3), the relative standard deviation (RSD) was estimated to be 2.3%, current respond toward DA remains 92.79% after several day, showing a good stability, repeatability and selectivity. Moreover, compared with other similar DA sensors, the linear range of the sensor was 2 orders of magnitude wider, and the detection limit was 5 times lower. [ABSTRACT FROM AUTHOR]

Objective: Our aim was to evaluate the effectiveness of a modified 8-week reminiscence therapy on the burden, positive experience, and life satisfaction of older spouse caregivers and the life satisfaction of stroke survivors.Methods: We conducted a randomized controlled trial by using 75 older stroke couples recruited from communities in Zhengzhou, China. We randomly assigned participants to 1 of 3 groups: Group 1 (G1 , 25 couples, all attend intervention) and Group 2 (G2 , 22 couples, only caregivers attend intervention), who participated in a modified 8-week reminiscence therapy, and a waiting list (control) group (G3 , 28 couples). Interviewers blinded to treatment group assignment administered the life satisfaction to both stroke survivors and caregivers, caregiver burden, and positive experience for caregivers, at preintervention, immediately postintervention, and at 1 month and 3 months after cessation of the intervention.Results: We found a statistically significant interaction between treatment groups and assessment time points for the 4 outcome measures (P < .001). Although the effects were decreased after intervention at 1 month, the improvement in caregivers' positive experience, life satisfaction, burden, and life satisfaction of stroke survivors were still significant (P < .001).Conclusions: The use of a modified 8-week reminiscence therapy in this study sample improved the life satisfaction of stroke survivors and their spouse caregivers, improved the positive experience of caregivers, and decreased the burden of caregivers. [ABSTRACT FROM AUTHOR]