Thermal conductivity is a crucial parameter for managing exothermal gas adsorption in metal organic frameworks (MOFs), but experimental studies have been limited. In this work, the thermal conductivity of a zeolitic imidazolate framework ZIF-8 was experimentally determined on thin films using the 3ω technique at different partial pressures in perfluorohexane, nitrogen, air, and vacuum ambients at 300 K. In contrast to theoretical prediction, the thermal conductivity κ = 0.326 ± 0.002 W/m K was approximately independent of ambient gas species and pressure from atmospheric pressure to vacuum. This work introduces a useful approach for probing MOF thermal conductivity under gas adsorption.

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The cross-plane thermal conductivity of In-GaZnO (IGZO) thin films was measured using the 3ω technique from 18 to 300 K. The studied morphologies include amorphous (a-IGZO), semicrystalline (semi-c-IGZO), and c-axis-aligned single-crystal-like IGZO (c-IGZO) grown by pulsed laser deposition (PLD) as well as a-IGZO deposited by sputtering and by solution combustion processing. The atomic structures of the amorphous and crystalline films were simulated with ab initio molecular dynamics. The film quality and texturing information was assessed by X-ray diffraction and grazing incidence wide-angle X-ray scattering. X-ray reflectivity was also conducted to quantify film densities and porosities. All the high-density films exhibit an empirical powerlaw temperature dependence of the thermal conductivity κ ∼ T 0.6 in the specified temperature range. Among the PLD dense films, semi-c-IGZO exhibits the highest thermal conductivity, remarkably exceeding both films with more order (c-IGZO) and with less order (a-IGZO) by a factor of 4. The less dense combustion-synthesized films, on the other hand, exhibited lower thermal conductivity, quantitatively consistent with a porous film using either an effective medium or percolation model. All samples are consistent with the porosity-adapted Cahill−Pohl (p-CP) model of minimum thermal conductivity.

Background Coronary heart disease has become a serious challenge to China with its high prevalence and mortality. The impaired glucose regulation is prevalent in patients with cardiovascular disease. However, there are few drugs that interfere early with impaired glucose regulation. Ginkgo biloba extract not only is a commonly used drug for cardiovascular diseases, but also has a significant effect in reducing blood sugar. Therefore, this study used a single-case randomized controlled trial to explore the efficacy of Ginkgo biloba pills in the treatment of coronary heart disease patients with impaired glucose regulation. Methods/Design This is a randomized, double-blind, placebo-controlled, three-period crossover trial for a single subject. A total of 12 subjects will be recruited in this trial. The trial is divided into three cycles, and one cycle has two treatment periods. Ginkgo biloba pills and placebo will be randomized during the treatment period. The test period will last for 58 weeks and subjects will take 48 weeks. Subjects will be selected by the researcher strictly in accordance with the inclusion and exclusion criteria. Discussion Ginkgo biloba preparations are widely used in cardiovascular diseases both at home and abroad due to their definite curative effect, few side effects, various dosage forms, and convenient and safe use. Diabetes mellitus is a high-risk factor for the occurrence of cardiovascular disease. Therefore, it is of great significance to control the impaired glucose regulation and slow down the development of diabetes and reduce the incidence and mortality of cardiovascular diseases. This trial is registered with ClinicalTrials.gov (ID: NCT03483779).