Stuartwillard3065
Our dynamic contact angle data coincided with the prediction from a scaling law derived in this study.
The dynamic contact angles on LIS was found to be sensitive to changes in both the lubricant viscosity and the capillary number. The cube of the dynamic contact angles on the LIS was proportional to θD3~Ca1, which follows a conventional hydrodynamic theory. In addition, the decreasing lubricant viscosity shifted the cube of the dynamic contact angles to high capillary numbers. Our dynamic contact angle data coincided with the prediction from a scaling law derived in this study.Tuning the chemical composition and surface structure of electrodes is demonstrated as a feasible and effective strategy to tailor advanced catalysts for energy electrocatalysis. In this work, hierarchical palladium-silver alloy nanosheets (PdAg NS) with the thickness ~7 atoms and rich atomic defects are successfully prepared, using the carbon monoxide (CO) confinement approach. find more The optimized Pd7Ag3 NS/C exhibits 8.8 times higher catalytic peak current density and much better stability toward ethanol electrooxidation than Pd NS/C catalyst. The catalytic enhancement mechanism could be attributed to the synergetic effects among optimized electronic structure of Pd, novel architecture, and rich atomic defects.
In previous studies we looked at the foam stability of various surfactants with C
alkyl chains but different head groups and found that stable foams are only generated if the head groups are capable of forming hydrogen bonds with each other. Despite the consistency of the experimental data with the conclusions drawn from it we had no direct proof for our hypothesis that H-bonds are formed between surfactant head groups.
To fill this gap, i.e. to demonstrate intersurfactant H-bond formation, we chose the non-ionic sugar surfactant n-dodecyl-β-d-maltoside (β-C
G
) and used molecular dynamics (MD) simulations as well as grazing-incidence X-ray (GIX) scattering and diffraction to study the surfactant-loaded air-water interface.
(1) In a densely packed monolayer, close to the critical micelle concentration (cmc), each head group of the sugar surfactant is involved in ∼5 intersurfactant H-bonds with other head groups and in ∼5 H-bonds with water molecules. (2) The number of intersurfactant H-bonds decreasng revealed that a homogeneous surfactant monolayer is formed at full coverage (around the cmc), i.e. cluster formation only happens below the cmc.Traditional cobalt selenides as active materials in lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) would suffer from drastic volume expansions and large stacking effects, leading to a low cycling stability. In this work, we utilized a facile template method for preparing Co3Se4@N-CN (CSNC) that encapsulated Co3Se4 nanoparticles into 3D interconnected nitrogen-doped carbon network (N-CN). Satisfactorily, it possesses excellent cycling stability with enhanced lithium and sodium energy storage capacity. As an anode material in LIBs, CSNC exhibited a prominent reversible discharge performance of 1313.5 mAh g-1 after 100 cycles at 0.1 A g-1 and 835.6 mAh g-1 after 500 cycles at 1.0 A g-1. Interestingly, according to the analysis from cyclic voltammetry, the in-situ generated Se might provide extra capacity that leaded to a rising trend of capacity. When utilized as an anode in SIBs, CSNC delivered an outstanding capacity of 448.7 mAh g-1 after 100 cycles at 0.1 A g-1 and could retain 328.9 mAh g-1 (77.2% of that of 0.1 A g-1) even at a high current density of 5.0 A g-1. The results demonstrate that CSNC is a superior anode material in LIBs and SIBs with great promise. More importantly, this strategy opens up an effective avenue for the design of transition metal selenide/carbonaceous composites for advanced battery storage systems.Manganese-cerium metal oxide with flocculent structure prepared via the pyrolysis of Mn/Ce-MOF and supported Pd were applied for the catalytic oxidation of toluene. The Pd/Mn3Ce2-300 catalyst could completely oxidize toluene at 190 °C, which presented excellent catalytic performance. Moreover, Pd/Mn3Ce2-300 possessed great reusability, stability and water resistance even under 10 vol% water vapors. A series of characterizations including X-ray diffraction (XRD), N2 adsorption-desorption, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and H2 temperature programmed reduction (H2-TPR) were used to investigate the physicochemical properties of the samples. It was found that Pd/Mn3Ce2-300 possessed a better reduction ability at low temperature, more surface absorbed oxygen and surface Pd species, and a strong interaction between Pd and Mn3Ce2-300, resulting in great catalytic performance for toluene degradation.
To investigate the extent to which antibiotic exposure in the first 2 years of life is associated with the risk of immunological, metabolic, and neurobehavioral health conditions with childhood onset.
In this population-based cohort study, we identified all children born in Olmsted County, Minnesota, between January 1, 2003, and December 31, 2011, through the Rochester Epidemiology Project medical records-linkage system. Demographic characteristics, antibiotic prescriptions, and diagnostic codes through June 30, 2017, were retrieved using the Rochester Epidemiology Project infrastructure. Time-to-event analysis was performed to assess the impact of antibiotic exposure on the risk of several adverse health conditions.
This study included 14,572 children (7026 girls and 7546 boys), of whom 70% (10,220) received at least 1 antibiotic prescription during the first 2 years of life. Early antibiotic exposure was associated with an increased risk of childhood-onset asthma, allergic rhinitis, atopic dermatitis, celiac disease, overweight, obesity, and attention deficit hyperactivity disorder (hazard ratios ranging from 1.20 to 2.89; P<.05 for all). The associations were influenced by the number, type, and timing of antibiotic exposure. Moreover, children exposed to antibiotics had a higher probability of having combinations of conditions, particularly when given multiple prescriptions.
The present study finds significant associations between early life antibiotic exposure and several distinct health conditions with childhood onset. Additional research is warranted to establish practical guidelines to optimize the benefit and minimize the risk of antibiotics in children.
The present study finds significant associations between early life antibiotic exposure and several distinct health conditions with childhood onset. Additional research is warranted to establish practical guidelines to optimize the benefit and minimize the risk of antibiotics in children.