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Real-time detection of VOCs in the car cabin is crucial for protecting driver's health. MOS gas sensors, with the advantages of low cost, simplicity and fast response, are widely used for gas monitoring. However, they typically exhibit broad-spectrum responsiveness to multiple gases. Despite numerous improvement strategies proposed from the perspective of MOS material modification, achieving ideal gas selectivity remains challenging. An e-nose based on gas sensor array is a promising approach for gas identification. However, the hardware circuit system and battery supply module in traditional e-nose result in large size, complex structure, and inconvenience in use. In this work, we synthesized MOS materials with different morphologies to form a microarray containing six MEMS gas sensors, and developed a novel belt-shaped wireless and battery-free flexible e-nose, where a mobile phone serves as its wireless power supply and data communication system. This design provides a flexible e-nose with excellent wearability and safety, allowing users to monitor surrounding gas conditions at any time conveniently. Subsequently, we design pattern recognition models using algorithms such as MLP, RF, XGBoost, and LGBM, in combination with ensemble learning strategies, achieving high accuracy in VOCs classification and low-error concentration prediction. This flexible e-nose holds significant application value for gas detection in car cabins and indoor environments. [Display omitted] • A novel battery-free, wireless, flexible bandlike e-nose is developed. • The e-nose comprises a MEMS sensor array, wireless data transmission circuits, and a wireless power supply unit. • The mobile phone serves both as the power source for the e-nose and the recipient of data, offering convenience to use. • Users can obtain accurate VOCs detection information by simply bringing their phones close to the e-nose. • Pattern recognition models combined with ensemble strategies are designed to achieve gas recognition. [ABSTRACT FROM AUTHOR]

High-fidelity numerical simulation of compressible multi-phase flows is of great challenge due to its competing requirements for resolving complex flow structures with low dissipation and capturing moving interfaces as well as other discontinuities sharply. Recently, a novel hybrid scheme, combining the standard targeted essentially non-oscillatory (TENO) scheme with Tangent of Hyperbola for INterface Capturing (THINC) scheme as two building blocks for smooth and non-smooth regions respectively and thus named as TENO-THINC, has been proposed and shows great potential for resolving complex single-phase fluids. In this work, a high-order finite-volume method, based on the TENO-THINC scheme for spatial reconstruction and the Harten-Lax-van Leer contact (HLLC) approximate Riemann solver for flux evaluation, is developed for simulating compressible multi-phase flows with a reduced five-equation formulation of the diffuse-interface model. The TENO-THINC scheme deploys the THINC reconstruction to resolve the physical discontinuities as well as the material interfaces within a few cells, and is desired to resolve the interface evolution more reliably in multi-phase flow simulations. Several algorithms have been implemented and elaborated for ensuring the numerical robustness of extreme simulations with high density and pressure ratios. Numerical results of the 1D and 2D challenging benchmark tests show that the TENO-THINC scheme is more robust than the standard TENO scheme and less dissipative than both the TENO and WENO-JS schemes. This property is essential for the long-term simulations of compressible multi-phase flows. [Display omitted] • A high-order TENO-THINC scheme is developed to simulate multi-phase flows. • The numerical framework does not generate spurious oscillations. • The scheme will invoke THINC reconstruction near discontinuities and interfaces. • In the smooth region, the TENO-THINC scheme will restore the high-order accuracy. • A set of numerical techniques is developed for guaranteeing the numerical stability. [ABSTRACT FROM AUTHOR]

Deactivation of V 2 O 5 /TiO 2 catalysts during selective catalytic reduction (SCR) of NO by NH 3 , especially the alkali metal-induced deactivation, has received much attention in recent years. Many researches have been done using different poisoning methods to understand the deactivation behavior of catalyst in industry, but the results were somewhat inconsistent. This work compares the poisoning methods – wet impregnation, solid diffusion and vapor deposition from the viewpoint of deactivation rate and deactivation mechanism using V 2 O 5 –WO 3 /TiO 2 as the catalyst and KCl as the poisoning substance. Results indicate that deactivation extent of the catalyst depends not only on the quantity of KCl but also on how KCl is introduced to the catalyst, following an order of vapor deposition ≫ solid diffusion > wet impregnation. The presence of V 2 O 3 species due to interaction of K with oxygen in vanadium oxides is mainly responsible for the catalyst deactivation by wet impregnation. The formation of K 2 S 2 O 7 –V 2 O 5 eutectic is mainly responsible for the catalyst deactivation by solid diffusion at a higher K/V ratio and vapor deposition due to the significant decrease of NH 3 adsorption and increase in NH 3 oxidation activity. [ABSTRACT FROM AUTHOR]

Cyclic voltammetry and positronium (Ps) 3 γ -annihilation spectroscopy were applied to investigate pore interconnectivity/morphology of porous silica films fabricated with various loading of cetyltrimethyl ammonium bromide (CTAB). With increasing the ratio of CTAB up to 15 wt.%, the total charge Q , resulted from I − diffusion across the silica films, increased remarkably, indicative of formation of highly interconnected pores in the films prepared with more porogen. However, it decreased dramatically with further loading CTAB of 25 wt.%. Interestingly, 3 γ -annihilation fraction I 3 γ due to a triplet-state Ps ( ortho -positronium, o -Ps) emission from the silica films showed a similar behavior as a function of CTAB loading. The abnormal decrement in Q and I 3 γ in the film fabricated with 25 wt.% CTAB was well explained by formation of long nanochannels aligning parallel to the film surface. The results indicated that the total charge Q and Ps 3 γ -annihilation fraction were closely associated with I − and Ps diffusion governed by the pore interconnectivity/morphology of the silica films, which made cyclic voltammetry possible to be a feasible tool to characterize pore interconnectivity/morphology of porous thin films. [ABSTRACT FROM AUTHOR]

A new method of combined steam flash-explosion and alkaline treatment (SFE-AT) was developed to extract cellulose fibers from bark of cotton stalks, and lightweight composites with favorable properties were made from the obtained fibers and polypropylene (PP). It was reported that the cellulose fibers from bark of cotton stalks had higher mechanical properties than those from most lignocellulosic byproducts. However, conventional method of using strong alkaline condition (30–100 g/L NaOH) for extraction of cellulose fibers from lignocellulosic byproducts led to environmental pollution and high cost. In this study, bark of cotton stalks were treated using three methods, including alkaline treatment (AT), steam flash-explosion (SFE) and SFE-AT. The different cotton stalk fibers were blended with PP fibers and compression-molded into composites under optimized conditions (temperature of 170 °C, pressure of 3 MPa, 4 min). The results showed that PP composites reinforced by cotton stalk fibers from SFE-AT had the best mechanical properties and stability to water, attributing to the largest surface area and highest cellulose content of cotton stalk fibers by SFE-AT. SFE could separate bark of cotton stalks with high efficiency and subsequent mild AT could sufficiently remove the non-cellulose impurities by using NaOH solution with concentration as low as 5 g/L. Ultra-lightweight PP composites with the bulk density of 0.27 g/cm 3 could be prepared with cotton stalk fibers by SFE-AT. Overall, the method of SFE-AT with high efficiency and low cost could be very useful in exploring industrial applications of bark of cotton stalks and other lignocellulosic byproducts. [ABSTRACT FROM AUTHOR]

• A novel anticoagulant affinity membrane (AAM) was developed for bilirubin removal. • The protein-bound toxin was cleared in a pore-flow-through way. • Up to 86.1 % of bilirubin toxins were captured by the flexible PLA ligand. • The hemocompatibility was enhanced by the surface-bound heparin and PLA on the AAM. • The AAM has a very important potential for blood purification therapy. Affinity membrane is widely employed to promote specific adsorption of toxins and reduce the blood purification therapeutic time. However, it suffers from insufficient toxin binding and low hemocompatibility. Herein, a novel anticoagulant affinity membrane (AAM) was developed to clear bilirubin from human blood in a pore-flow-through way. Firstly, a nylon net membrane with a regularly arranged pore as the matrix was coated with poly(pyrrole-3-carboxylic acid) via chemical vapor deposition (CVD) method. Then, poly(L-arginine) (PLA) as a highly specific ligand of bilirubin, was immobilized onto the surface of the composited membrane after the modification of heparin. Owing to the 3-dimensional molecular architecture of PLA, up to 86.1 % of bilirubin was efficiently cleared. Besides, the AAM exhibited effective anticoagulant activity in the measurement of clotting time, with suppressed thrombus formation, low hemolysis ratio, minimized platelet and leukocyte adhesion, and excellent biosafety. Therefore, the AAM has enormous potential in blood purification therapy for enhancing hemocompatibility and bilirubin removal. [ABSTRACT FROM AUTHOR]