Stretchable thermoelectrics have recently attracted widespread attention in the field of self-powered wearable electronics due to their unique capability of harvesting body heat. However, it remains challenging to develop thermoelectric materials with excellent stretchability, durable thermoelectric properties, wearable comfort, and multifunctional sensing properties simultaneously.

ObjectivesTo evaluate student tobacco control advocacy behavioural capacity using longitudinal trace data.MethodsA tobacco control advocacy curriculum was developed and implemented at schools of public health (SPH) or departments of public health in seven universities in China. Participants comprised undergraduate students studying the public health curriculum in these 13 Universities. A standardised assessment tool was used to evaluate their tobacco control advocacy behavioural capacity. Repeated measures analysis of variance, paired t tests and paired χ2 tests were used to determine differences between dependent variables across time. Multivariate analysis of variance (MANOVA) and multivariate logistic regression were used to assess treatment effects between intervention and control sites.ResultsRespective totals of 426 students in the intervention group and 338 in the control group were available for the evaluation. Approximately 90% of respondents were aged 21 years or older and 56% were women. Findings show that the capacity building program significantly improved public health student advocacy behavioural capacity, including advocacy attitude, interest, motivation and anti-secondhand smoke behaviours. The curriculum did not impact student smoking behaviour.ConclusionsThis study provides sufficient evidence to support the implementation of tobacco control advocacy training at Chinese schools of public health.

Solar steam generation has been considered a promising approach for using renewable solar energy to produce clean water from seawater and wastewater. It shows great potential for alleviating water shortages. However, salt accumulation and system longevity are challenges which impede the widespread use of evaporators. This paper reports a stable Janus evaporator with thickness controllable hydrophilic and hydrophobic layers based on cellulose composite aerogels, which were extracted from waste cotton fabric by a two-step freeze-drying process. The obtained glutaraldehyde cross-linked carbon nanotubes/cellulose Janus aerogel exhibited an attractive solar steam generation rate of 1.81 kg·m–2·h–1 and a light-to-vapor efficiency of up to 92.5% in 1 sun illumination. Moreover, the Janus solar steam generator could pledge stable and sustainable solar-driven water evaporation performance within a 10 h test, showing a high salt-resistant property in simulated seawater. In addition, the developed solar evaporator also had a good purification effect on dye wastewater. These findings suggest its potential ability for seawater desalination and wastewater purification.

Preventation of shale formation damage by fracturing fluid-rock interactions plays an important role in well production performance and subsequent refracturing design. In this paper, the effect of converting typically hydrophilic fracture surface to hydrophobic ones on fluid-induced damage and softening is investigated. In particular, nanoindentation experiments were employed to characterize changes in the mechanical properties of shale samples with different surface treatments. Shale samples were treated by octadecyltrimethoxysilane (OTMS) to convert the initially hydrophilic surfaces to hydrophobic ones, followed by inundation in water to allow for fluid-rock interactions. Nanoindentation testing was then conducted on the samples to characterize hardness, Young's modulus, and fracture toughness to examine the effect of fluid-rock interactions on shale mechanical properties and whether surface treatment can mitigate shale-softening. Its unique advantage is that the near-surface properties (but not the entire bulk sample) can be characterized, thus elucidating how water-rock interactions migrate from the surface to the interior of the rock. Results obtained from nanoindentation testing were analyzed by statistical analysis and by a proposed clay matrix criterion. Different treatments lead to variable alterations to rock properties. The hardness and Young's modulus exhibit a reciprocal steady state trend at certain depths. Samples with hydrophobic surfaces exhibit a higher resistance to fluid-shale interactions, as reflected by a 40% higher hardness, a 25% higher Young's modulus, and a 35% higher fracture toughness, when compared with untreated shale samples. The untreated rock actually shows a 48% reduction in hardness, a 27% reduction in Young's modulus, and a 43% reduction in fracture toughness in the rock interior. This study also demonstrates that nanoindentation testing provides multiple advantages in characterizing the fracturing fluid-rock interactions at the micro/nano scale, since these interactions start from the rock surface and propagate to the interior without significantly involving the bulk rock. Nanoindentation testing is competent in characterizing micromechanically fluid-shale interactions and how surface treatment can mitigate the softening of shales.

Foi desenvolvido um método altamente sensível, seletivo e rápido para a determinação de mercúrio, a partir da reação rápida de mercúrio(II) com 5-(p-aminobenzilideno)-tiorodanina (ABTR) e posterior extração em fase sólida do quelato colorido, utilizando discos C 18 . Em pH 3,5 e na presença do emulsificante-OP, ABTR reage com mercúrio(II) para formar um quelato vermelho na razão molar 1:2 (mercúrio:ABTR). O quelato foi enriquecido pela extração em fase sólida com discos C 18 e o quelato retido, eluído com dimethyl formamida (DMF). Um fator de enriquecimento na ordem de 50 foi obtido. Em DMF, a absortividade molar do quelato é 1,21×10 5 L mol -1 cm -1 a 545 nm, e a lei de Beer é obedecida no intervalo 0,01~3 μg mL -1 na solução medida. O desvio padrão relativo para onze replicatas a 0,01 μg mL -1 é 1,7%. Este método foi aplicado para a determinação de mercúrio em tabaco e aditivos de tabaco. Bom coeficiente de preconcentração foi encontrado, comparando-se o método proposto com outros similares.A highly sensitive, selective and rapid method for the determination of mercury based on the rapid reaction of mercury(II) with 5-(p-aminobenzylidene)-thiorhodanine (ABTR) and the solid phase extraction of the colored chelate with C 18 disks has been developed. At pH 3.5 and in the presence of emulsifier-OP medium, ABTR reacts with mercury(II) to form a red chelate of a 1:2 (mercury to ABTR) molar ratio. This chelate was enriched by solid phase extraction with C 18 disks and the retained chelate eluted form the disks with dimethyl formamide (DMF). An enrichment factor of 50 was achieved. In the DMF medium, the molar absorptivity of the chelate is 1.21×10 5 L mol -1 cm -1 at 545 nm, and Beer's law is obeyed in the 0.01~3 μg mL -1 range in the measured solution. The relative standard deviation for eleven sample replicate measurements at the 0.01 μg mL -1 level is 1.7%. This method was applied to the determination of mercury in tobacco and tobacco additives and good preconcentration was found between proposed and comparative methods results.