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[Display omitted] The rapid recombination of interfacial charges is considered to be the main obstacle limiting the photocatalytic CO 2 reduction. Thus, it is a challenge to research an accurate and stable charge transfer control strategy. MIL-53 (Al)-S/Cd 0.3 Zn 0.7 S (MAS/CZS-0.3) photocatalysts with chemically bonded interfaces were constructed by in-situ electrostatic assembly of sulfur defect Cd 0.3 Zn 0.7 S (CZS-0.3) on the surface of MIL-53 (Al) (MAW), which enhanced interfacial coupling and accelerated electron transfer efficiency. An adjustable proportion of syngas (H 2 /CO) was prepared by photothermal catalytic CO 2 reduction at micro-interface. and the optimal yield of CO (66.10 μmol∙g−1∙h−1) and H 2 (71.0 μmol∙g−1∙h−1) was realized by the MAS/CZS-0.3 photocatalyst. The improved activity was due to the photogenerated electrons migrated from CZS-0.3 to the adsorption active sites of MAS, which strengthened the adsorption and activation of CO 2 on MAS. The photothermal catalytic CO 2 reduction to CO follows the pathway of CO 2 →*COOH → CO and CO 2 →*HCO 3 –→CO. This work provided a reference for the research, characterization, and application of in-situ anchoring of metal organic frameworks in photothermal catalytic CO 2 reduction, and provided a green path for the supply of Syngas in industry. [ABSTRACT FROM AUTHOR]

• A unified dynamic model of eccentric curve-face gear system was established. • Dynamic equation was derived through Lagrange bond diagram. • The dynamic response of the system is a highly nonlinear process • The gear eccentricity can modulate both amplitude and frequency. • Frequency components and amplitudes of different tooth profiles were different. This paper establishes a dynamic model and a Lagrange bond diagram model for the eccentric curve-face gear transmission system. The dynamic model includes a gear meshing model, a lumped-parameter supporting model, a drive and a load, etc. Considering the impact of cam effect and inertia force caused by gear eccentricity, the dynamic equations are established based on the Lagrange bond diagram model. Moreover, the parameters of the model are analyzed deeply, the effects of gear eccentricity, helical angle, tooth profile of gear pairs, and input velocity on the vibration response in time and frequency domain are studied. It is found that the dynamic response of the eccentric curve-face gear transmission system is a highly nonlinear process. The gear eccentricity can modulate both amplitude and frequency. Introducing a force-locking spring in the eccentric curve-face gear transmission system with helical-teeth will negatively affect the system, resulting in the increase of vibration amplitude. The time-varying helical angle of the eccentric curve-face gear transmission system with circle-arc teeth will also have a negative effect on the dynamic characteristics and cause more small pulses. The axial dynamic response, bending dynamic response, and torsion dynamic response are more sensitive than the radical dynamic response to the change of helical angle. Finally, the correctness of numerical analysis was verified through experimental studies. [ABSTRACT FROM AUTHOR]

Perfluoroalkyl chemicals (PFCs) are widely detected in the environment and human body, and they have been linked to asthma and a number of respiratory responses in children and mice. However, no previous studies have investigated the association between exposure to PFCs and airway inflammation in adults. To evaluate the associations between serum PFCs and fractional exhaled nitric oxide (FeNO), a biomarker of airway inflammation, in adults. A cross-sectional study of 3630 adults aged 20–79 years who participated in the National Health and Nutrition Examination Survey (NHANES, 2007–2012) was conducted. Serum concentrations of five major PFCs were measured using SPE-HPLC-TIS-MS/MS method, including perfluorohexane sulfonic acid (PFHxS), perfluorononanoic acid (PFNA), perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), and perfluorodecanoic acid (PFDE). The detection rates of them were all >85%. Weighted multivariable linear regression and Bayesian kernel machine regression (BKMR) analyses were applied to examine the associations between serum PFCs and FeNO. After adjusted for potential confounding factors, linear regression analyses found that compared with their lowest tertiles, highest tertiles of PFOS, PFDE and PFOA were significantly associated with 5.02% (95% CI: 1.40%, 8.77%), 3.77% (95% CI: 0.30%, 7.36%) and 6.34% (95% CI: 2.81%, 10.01%) increases in FeNO, respectively. The second tertile of PFNA was significantly correlated with a 4.79% (95% CI: 1.41%, 8.29%) increase in FeNO compared with the lowest tertile. In the BKMR analysis, the mixture effect of PFCs on FeNO increased significantly when the PFC levels were at or above the 60th percentiles compared to those at their medians. PFOS and PFOA displayed significant positive single-exposure effects on FeNO when all the other PFCs are set at a particular threshold. This study provided preliminary evidence that serum PFCs were positively associated with increased FeNO in adults. [Display omitted] • The association of exposure to PFCs with FeNO was firstly assessed in adults. • PFOS, PFDE, PFOA, PFHxS and PFNA could be detected in >85% of adults. • Linear regression analyses showed positive associations between PFCs and FeNO. • The mixture of five PFCs had an overall effect on increased FeNO. • PFOA and PFOS displayed positive single-exposure effects on increased FeNO. [ABSTRACT FROM AUTHOR]