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Electrospun fibrous structures can be developed superhydrophobic while remaining breathable. However, current electrospinning‐based methods for developing superhydrophobicity require complex fabrication processes and multiple raw materials, lacking a facile approach to superhydrophobicity using electrospun fibers. Inspired by a cultural relic known as Plain Gauze Gown, a fibrous structure consisting two layers of porous fibers aligned in warp and weft directions by simple electrospinning is developed. Through investigation of wetting behavior, an unique Cassie–Baxter‐"restoring" (CaRe) wetting contributing to a stable Cassie–Baxter state is unveiled in the developed structure. The CaRe wetting ensures that droplet stays on the upper‐layer fibers even at a sparse inter‐fiber distance, enabling strategically reaching superhydrophobicity by lowering structure solidity. Remarkably, the developed structure with water contact angle between 159° and 162° and roll‐off angle from 10° to 3° has a water vapor transmission rate of 20.8 kg m−2 d−1, which is the highest value among all superhydrophobic electrospun structures reported, and it is also waterproof and semi‐transparent. These features make the structure suitable for a wide range of applications, including developing waterproof, breathable, and superhydrophobic membrane with simple preparation and low cost, and as a surface layer for wearable electronics that facilitates sweat evaporation and prevents water intrusion. [ABSTRACT FROM AUTHOR]

The cyclonic micro‐bubble flotation column (FCMC) is an efficient flotation device for the separation of fine minerals, but its mechanisms are rarely studied using computational fluid dynamics (CFD). This paper reports the air–water two‐phase computational fluid dynamics‐population balance model (CFD‐PBM) simulations for the column flotation unit of an FCMC. The shear stress transport (SST) k‐ω model with curvature correction (CC) is used to simulate turbulence effects. Then, the interphase forces models considering bubble size distribution are selected according to the experimental data in a bubble column, which is in analogy to the column flotation unit of the FCMC. Finally, the optimal combination of interphase forces models (i.e., the Ishii–Zuber drag force model, the Hosokawa–Frank wall lubrication force model, and the Lopez de Bertodano turbulent dispersion force model) is applied to simulate an FCMC with a superficial gas velocity of 0.0144 m/s. The results show that the CFD‐PBM simulation can achieve a relative error of 9.09% for gas volume fraction and −5.45% for bubble rising velocity, indicating the reliability of the selected combination of interphase forces models. [ABSTRACT FROM AUTHOR]

This paper presents and compares the mathematical models and computational fluid dynamics (CFD) models for degassing of oxygen from water in a laboratory-scale multi-function gas-liquid contactor under various operating conditions. The optimum correlations of the overall volumetric liquid-phase mass transfer coefficient ( k L a ) are determined by the mathematical models of specific contactors. Both the continuous-reactor model and semi-batch model can evaluate the degassing efficiency with relative errors within ±13%. Similarly, CFD models agree with experimental data with relative errors of ±10% or less. Overall, the mathematical models are deemed easy to use in engineering practice to assist the selection of efficient contactors and determine their optimum operation parameters. The CFD models have a wider applicability, and directly provide the local mass transfer details, making it appropriate for harsh industrial scenarios where empirical correlations for important quantities are unavailable. Combining these two types of models can effectively guide the design, optimization, and operation of the high-throughput degassing system. [ABSTRACT FROM AUTHOR]

The widely acknowledged water splitting catalysis as an alternative to fossil fuel combustion becomes unproductive due to the involved sluggish oxygen evolution reaction (OER) kinetics. Therefore, it is extremely urgent and significant to develop an inexpensive OER catalyst with fast reaction dynamics, high efficiency and long-term stability. To address such issues, herein, for the first time, we present a novel vertical Fe(OH)3/Ni9S8 nanoarrays electrocatalyst that can rapidly fabricated on etched stainless steel (ESS) via a facile and swift electrodeposition process. The Fe(OH)3/Ni9S8/ESS exhibits excellent OER performance with ultra-low overpotential of 206 mV at 10 mA cm−2 (far better than RuO2/ESS) and shows outstanding long-term stability. The terrific OER performance can be attributed to the integration of well-designed nanoarchitecture, and the coupling effect between Fe(OH)3 and Ni9S8. The direct nanoarrays electrodeposition on highly conductive ESS substrate not only facilitate the rapid electron transfer for enhanced performance, but also improve the mechanical properties to ensure long-term stability. Additionally, the well-designed porous nanoarray guarantees abundant catalytically active sites exposure, facilitate the electrolyte penetration and promote the O2 bubble release. Interestingly, the systematically fabricated Fe(OH)3 outer layer can prevent the direct contact of Ni9S8 layer with alkaline electrolyte to avoid surface oxidation during catalysis. This work provides a systematic strategy to rationally design and facilely fabricate low-cost electrocatalysts with outstanding OER performance. [ABSTRACT FROM AUTHOR]

Experiments were conducted in a bubblecolumn to determine theequilibrium constants of reactions between NO and ammoniacal cobalt(II)solutions at temperatures between 298.15 and 310.15 K and pH valuesfrom 9.06 to 9.37 under atmospheric pressure. The two reactions are2Co(NH3)5(H2O)2++ 2NO⇌ (NH3)5Co(N2O2)Co(NH3)54++ 2H2O and2Co(NH3)62++ 2NO ⇌ (NH3)5Co(N2O2)Co(NH3)54++ 2NH3, respectively. Theirequilibrium constants are calculated on the fraction molar basis.All experimental data fit well to the equations ln KNO5= 3598.5(1/T) + 16.759 and ln KNO6= 1476.4(1/T) + 26.597, which give the enthalpy of reactions between NO and penta-and hexaamminecobalt(II) nitrates: ΔrH5° = −29.92kJ·mol–1and ΔrH6° = −12.27kJ·mol–1. [ABSTRACT FROM AUTHOR]

Bismuth tungstate (Bi 2 WO 6 ) nanomaterials are widely used as visible-light driven photocatalysts. However, limited attention has been paid to the purity of prepared Bi 2 WO 6 nanoparticles, which may affect the photocatalytic performance and hinder in-depth study of Bi 2 WO 6 . In this work, the impurities of Bi 2 WO 6 formed during the hydrothermal process under a wide range of acid-base conditions (from 1.5 M HNO 3 to 0.5 M NaOH) were qualitatively analyzed and accurately quantified for the first time. After confirmation of Bi 2 WO 6 stability, the impurities were dissolved using acid or base treatment, followed by measurements of the ion concentrations using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Furthermore, various characterization techniques including XRD, FE-SEM, TEM, UV-Vis DRS, XPS and FTIR were implemented to explore the change in morphology and optical properties of Bi 2 WO 6 prepared in different acid-base environments, and to facilitate qualitative analysis of impurities. The hydrolytic properties of raw materials used for the synthesis of Bi 2 WO 6 were also analyzed with UV-Vis transmittance observation. Following these analyses, the types and contents of impurities in Bi 2 WO 6 prepared by the hydrothermal method under different acid-base conditions were determined. Results show that the primary impurity is WO 3 ·0.33H 2 O (41.09%) for the precursor prepared in 1.5 M nitric acid solution. When the pH of the precursor was in the range of 0.97-7.01, the synthesized Bi 2 WO 6 has relatively high purity, and the impure products were identified as BiONO 3 . Bi 2 O 3 began to appear when pH reached 9.01 and it reached 18.88% when pH was 12.98. The final product was Bi 2 O 3 exclusively for the precursor conditioned in 0.5 M NaOH solution. In addition, the accuracy of the proposed quantitative method using ICP-MS was validated for several scenarios by weight difference experiments., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Osteoclasts dissolve bone through acidification of an extracellular compartment by means of a multimeric vacuolar type H+-ATPase (V-ATPase). In mammals, there are four isoforms of the 100-kDa V-ATPase "a" subunit. Mutations in the a3 isoform result in deficient bone resorption and osteopetrosis, suggesting that a3 has a unique function in osteoclasts. It is thus surprising that several studies show a basal level of a3 expression in most tissues. To address this issue, we have compared a3 expression in bone with expression in other tissues. RNA blots revealed that the a3 isoform was expressed highest in bone and confirmed its expression (in decreasing order) in liver, kidney, brain, lung, spleen, and muscle. In situ hybridization on bone tissue sections revealed that the a3 isoform was highly expressed in multinucleated osteoclasts but not in mononuclear stromal cells, whereas the a1 isoform was expressed in both cell types at about the same level. We also found that a3 expression was greater in osteoclasts with 10 or more nuclei as compared with osteoclasts with five or fewer nuclei. We hypothesize that these differences in a3 expression may be associated with previously demonstrated differences between large and small osteoclasts with reference to their resorptive activity.