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Ceramic nanofibrous aerogels have attracted great interest because of their extraordinary multifunctional properties. Herein, a facile strategy was proposed to create SiO 2 nanofibers-BN nanoribbons assembled binary aerogel with excellent temperature-invariant super-flexibility, as well as low thermal conductivity, low infrared radiation and excellent sound absorption properties. In addition, the unique structure of the nanofibers-nanoribbon aerogel acts as the thermal insulation layer, combined with Al foil acting as an infrared reflection layer, forming a component that can effectively hide high infrared targets. The nanofibrous-nanoribbons binary aerogel possess low thermal conductivity (0.0288 W/(m⋅K)) and outstanding sound-absorption ability (NRC value of 0.43), as well as excellent infrared stealth ability, which makes it an ideal candidate for thermal insulation and sound absorption in multi fields. [ABSTRACT FROM AUTHOR]

In this work, an environmentally friendly, superhydrophobic and durable modified melamine sponge was fabricated through a simple two-step dipping method. Through this strategy, the active carbon (AC) particles and reduced graphene oxide (rGO) were fixed on the melamine sponge skeleton with polydimethylsiloxane (PDMS) glue to form MS/rGO/AC/PDMS sponge, which has a multi-stage pore structure. Water contact angle (WCA) revealed that the as-prepared sponge possessed excellent water repellency up to 164°. Being applied in the field of oil/water separation, MS/rGO/AC/PDMS exhibited excellent oil-water selectivity, high oil sorption ability up to 120 g/g, and separation efficiency of over 99.85%. It is worth noting that under complex environments such as acid-base, fatigue and abrasion, the obtained sponge can maintain original properties, and the water contact angle exceeds 154°. In addition, it has good mechanical stability which can be reused and recovered continuously, making it a potential material for practical applications. [ABSTRACT FROM AUTHOR]

Herein, a novel flexible SiO 2 aerogel composite nanofiber membrane with strawberry-like structure and excellent thermal insulation properties, in which SiO 2 aerogel particles act as thermal insulation filler, was prepared by electrospinning technology. With the addition of nano-pore structure SiO 2 aerogel particles, the heat transfer path of the fibers inside the membrane became discontinuous, endowing the as-prepared membrane an ultra-low thermal conductivity of 30.3 mW/(m⋅K) and large surface area of 240 m2/g. Moreover, the nanofibers membrane also possesses the combined merits of excellent fire resistance, high-temperature stability, and temperature-invariant flexibility, rendering it a promising in the application of insulation and gas adsorption. The successful preparation of this flexible nanofiber membrane paves a new way to design materials with excellent thermal insulation and adsorption properties. [ABSTRACT FROM AUTHOR]

Environmental noise has been regarded as major noise pollution with severe hazards to human physical and mental health. The common commercial fiber sound-absorption materials have insufficient low frequencies wave absorbing and fire-resistant ability, limiting their wide application. To solve these problems, a novel strategy combining flexible nanofibers and rGO/MXene nanosheets was proposed to fabricate rGO/MXene/SiO 2 nanofibers composite aerogel with hierarchically porous structure, which possessed an extremely low density of 9.8 mg/cm3 and superior low-frequency sound absorption ability (NRC value of 0.51). The obtained composite aerogel possessed a large deformation up to 80% (corresponding compressive stress of 17 kPa) and quickly recovered. In addition, the as-prepared aerogel could be easily produced on a large scale, providing a reference for the development of new generation of sound-absorbing products. [ABSTRACT FROM AUTHOR]

Cervical insufficiency is a major cause of second-trimester pregnancy loss and spontaneous preterm delivery. Transabdominal cervicoisthmic cerclage is usually performed before pregnancy for patients of cervical insufficiency, in whom transvaginal cervical cerclage procedure cannot be placed or has failed previously. Performing a transabdominal cerclage becomes a huge challenge owing to the enlargement of the pregnant uterus in patients who were indicated for transabdominal cervicoisthmic cerclage but were missed before pregnancy. Here, we have outlined an easy and effective surgical procedure as needle-free laparoscopic trans-broad-ligament cervicoisthmic cerclage during early second-trimester. Laparoscope with 4 trocars was established, after expanding the trigonum of ureter, ovarian vascular and ascending branch of uterine artery. The needleless Mersilene tape was inserted in a posterior-to-anterior direction of bilateral trigonums, tightening the knot toward the bladder uterine reflection and simultaneously pushing the loop behind the uterus, directed to the cervix progressively. The tape was then tied anteriorly at the cervico-isthmic junction with 5 to 6 intracorporeal square knots after transvaginal ultrasound determined the presence of systolic velocity of uterine artery with first knot. The primary feature of our procedure was that the needleless Mersilene tape was inserted centrally from the broad ligaments, lateral to the uterine vessels, and finally tied above the uterosacral ligament at the level of the uterine isthmus, without dissecting the bladder off from lower uterine segment and without separating the uterine vessels from the lateral wall of the cervix. We performed this procedure on 10 patients with pregnancy outcomes and there was no pregnancy loss. This procedure proved to be an accessible and effective surgical technique for transabdominal cerclage of the uterine cervix during early-second trimester, with affirmative prognosis. [ABSTRACT FROM AUTHOR]

The deformation characteristics of Chinese yam during multiphase microwave drying (MMD) was evaluated by image processing, and the effects of MMD on the drying characteristics, physical properties, shrinkage behavior, and microstructure of the samples were also investigated. The drying time was significantly reduced by increasing microwave power density. Compared with Scheme I, the time of Scheme V was shortened by 22.22%. The moisture content at the transition point from sublimation to evaporation drying stages (TP S-E) significantly affected the shrinkage of the samples. In Scheme I, the lowest moisture content at TP S-E of 0.354 g. g−1 was found, and the dried products with the shrinkage ratio and bulk density closest to those of FD. The deformation of Chinese yam mainly appeared in the evaporation drying stage. At this stage, the rate of change in cross-sectional area of dried samples ranged from 9.74% to 26.76% for Schemes II to Scheme V, compared to 2.03% for Scheme I. Similarly, the shrinkage ratio of the dried samples in Schemes II, III, IV, and V increased from 16.82% to 21.12% at TP S-E to 29.23% to 51.28% at the end of drying, respectively. Additionally, the shrinkage caused by the pores collapse of the samples because of the high moisture content at TP S-E (Scheme III, IV, and V) during the evaporation drying stage resulted in increases of bulk density. The present study can provide valuable insights for rational control of shrinkage and deformation of fruits and vegetables in MMD. Chinese yam is a widely used food and medicinal resource in China due to its rich nutritional and medicinal values. Since the moisture content of Chinese yam can reach as high as 70–80%, drying serves as an effective method to broaden its application. However, shrinkage and deformation of materials during drying are common forms of appearance deterioration that can directly impact consumer acceptability. MMD has proven to be a promising drying technology. Nevertheless, improper drying parameter settings may lead to a deterioration of the appearance quality of MMD products. Therefore, comprehending the information of shrinkage and deformation of Chinese yam during MMD and effectively regulating these processes is essential. Mastering these aspects is critical for enhancing the economic value and consumer acceptance of dried Chinese yam products. • The moisture content at transition point was affected by microwave power density. • The sample cross section's deformation was the middle part of edge shrinking towards center. • Samples' shrinkage deformation was more severe when water content at TP S-E was higher. • Higher microwave power density affected the microstructure of the samples. [ABSTRACT FROM AUTHOR]

Membrane-aerated biofilm reactors (MABRs) are a promising biofilm technology for wastewater treatment; however, achieving high pollutant removal in MABR systems with a low specific membrane surface area, low air-based aeration pressure and flexible aeration control remains a substantial challenge. In this study, a flexible and adjustable plate membrane module was developed and applied in an air-based plate MABR (PMABR) for treating anionic surfactant wastewater. The plate membrane module achieved high oxygen mass transfer under a low air-based membrane aeration pressure. When the influent linear alkylbenzene sulfonate (LAS) load was 0.559±0.010 kg/m3·d and a gradient-pressure membrane aeration scheme of (8,7,6) kPa was adopted, the LAS removal rate reached 99.2±0.1 %, and the LAS removal load per unit membrane area reached 14.08±0.25 g/m2·d. The bacteria participating in the degradation of LAS were mainly Parvibaculum , Pseudomonas , Desulfovibrio , Flavobacterium and Holophagaceae. The dominant microbial communities of different biofilms in the PMABR played an important role in ω-oxidation, β-oxidation, benzene ring breaking and sulfonic acid group shedding in the degradation of LAS. The developed plate membrane module and PMABR provide a clean, energy-saving and flexible technical solution for MABR applications in wastewater treatment. [Display omitted] • A plate membrane module for membrane-aerated biofilm reactors was developed. • Clean, energy-saving treatment of wastewater containing anionic surfactants was realized. • Gradient-pressure membrane aeration was used to achieve LAS degradation. • The relationship between LAS degradation and sulfate production was explored. • A high LAS removal load per unit membrane area was achieved at low aeration pressures. [ABSTRACT FROM AUTHOR]

In this study, laser ablation-resistant composite coating consisting of zirconium diboride (ZrB 2) particulate and silicon carbide (SiC) whisker with zirconia (ZrO 2)-sol binder was prepared to meet requirements of anti-laser ablation ability. Laser ablation behavior of as-prepared coating was investigated under varying laser powers. Results revealed that the highest back-surface temperature of coated aluminum substrate was only 150 °C when irradiated at a power density of 6.3 kW/cm2 for 10 s, which is below the maximum allowable temperature of the aluminum alloy substrate (200 °C). After ablation for 10 s, the mass ablation rate of the composite coating was 4.45 mg/s. Apparently, the composite coating exhibited outstanding ablation resistance against high-intensity continuous laser irradiation. At initial stage of ablation, combination of self-healing effect of liquid ZrO 2 –SiO 2 layer and volatilization of B 2 O 3 provide effective joint protecting mechanism. With increasing ablation time, ZrO 2 ceramic barrier layer, product of the pyrolysis of ZrO 2 gel and ZrB 2 filler, becomes progressively more important in maintaining excellent laser ablation resistance behavior, which is normally effective at around ablation pit. [ABSTRACT FROM AUTHOR]

In this study, N/O co-doped cage-type biomass carbon (NOBC) was prepared through a simple and facile hydrothermal reaction and two-step carbonization method. As the anode of a potassium ion battery, NOBC displays a superhigh long-cycling performance and a super high rate performance. NOBC-2 provides an excellent reversible capacity of 251.2 mAh g−1 after 1500 cycles at 0.5 A g−1, and an excellent performance of 334.6 mAh g−1 at a high current density of 5 A g−1 (after 2000 cycles). The reversible capacity of 124.19 mAh g−1 can be maintained even after 5000 cycles at 10 A g−1. The excellent performance of NOBC is attributed to the unique hollow cage structure, internal 3D carbon network structure and N/O co-doping. Based on the results of detailed fundamental analysis, the pseudo-capacitance mechanism contributes to the higher K ion storage process in NOBC-2. Density functional theory (DFT) calculations further show that N/O double doping can promote the adsorption of K ions in biomass carbon materials and improve the conductivity of the materials. The simple synthesis route and excellent electrochemical performance provide new insights for the search for novel carbon-based K storage anode materials with high energy and long cycle life. The N/O co-doped biomass carbon material (NOBC-2) is synthesized through a simple hydrothermal reaction and two-step carbonization, and exhibits surprisingly high energy and long cycle life stability in the potassium ion half-cell. [Display omitted] • The preparation method of N/O co-doped biomass carbon material (NOBC-2) is simple and convenient.There are wide sources of biomass raw materials, and mass production is expected. • There are wide sources of biomass raw materials, and mass production is expected. • NOBC-2 exhibits surprisingly high energy and long cycle life in potassium ion half-cells. • Mechanism studies are designed to investigate the K+ storage behaviors. [ABSTRACT FROM AUTHOR]