Both electron and phonon transport properties of single layer MoS2 (SLMoS2) are studied. Based on first-principles calculations, the electrical conductivity of SLMoS2 is calculated by Boltzmann equations. The thermal conductivity of SLMoS2 is calculated to be as high as 116.8 Wm−1K−1 by equilibrium molecular dynamics simulations. The predicted value of ZT is as high as 0.11 at 500 K. As the thermal conductivity could be reduced largely by phonon engineering, there should be a high possibility to enhance ZT in the SLMoS2-based materials.

Objective: To evaluate the effects of prepregnancy BMI and weight change from prepregnancy to postpartum on postpartum type 2 diabetes (T2D) risk among women with gestational diabetes (GDM). Methods: A retrospective cohort study in 1,263 GDM women at 1-5 years after delivery was performed. Cox proportional hazards regression models were used to evaluate the association of prepregnancy BMI and weight change with T2D and prediabetes risks. Results: The multivariable-adjusted hazard ratios based on different levels of prepregnancy BMI (<23, 23-24.9, 25-29.9, and 30 kg/m 2 ) were 1.00, 1.77, 2.35, and 6.54 (P trend < 0.001) for incident T2D, and 1.00, 1.46, 1.87, and 1.79 (P trend < 0.001) for incident prediabetes, respectively. Compared with women with stable weight (63 kg), those with weight gain 7 kg had an 86% and a 32% increased risk of diabetes and prediabetes, and those with weight loss 3 kg had a 45% decreased risk of prediabetes. The positive associations of prepregnancy BMI with incident diabetes and prediabetes risk were persistent in women with different levels of weight change (<3 kg and 3 kg). Conclusion: Prepregnancy obesity and excessive weight gain from prepregnancy to postpartum increase postpartum diabetes and prediabetes risks among GDM women.

By removing the oxygen-containing functional groups, thermal treatment in inert gas has been widely reported to improve the hydrophobicity of carbon materials. However, this work reports a contrary phenomenon for the nitrogen-doped graphene aerogel (NGA). As the temperature of thermal treatment increases from 200 to 1000 °C, NGA becomes more and more hydrophilic and the superwetting property remains for weeks in air. To uncover this unusual phenomenon, the effect of nitrogen doping is studied through both experiment and MD simulations. The effects of air exposure and air humidity are further investigated in detail to illustrate the whole physical picture clearly. The superwetting behavior is attributed to the preferential adsorption of water molecules to the nitrogen-doped sites, which significantly inhibits airborne hydrocarbon adsorption. In combination with the excellent properties including mechanical elasticity, high light absorption, and good thermal insulation, an efficient photothermal and solar steam generation performance is demonstrated by using NGA-600 as the photothermal material, presenting a high energy conversion efficiency of 86.2% and good recycling stability.

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