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•GYbZ TBCs with triple-scale micro/nano structure were successfully prepared by ultrafast laser direct writing along with PS-PVD technology.•The triple-scale structure consists of ...conical micro-pillars, cauliflower-like domed micro-protuberances and nano particles.•The re-constructed PS-PVD TBCs possesses superior thermal stability and long-term high-temperature silicophobicity.•The rapidly developed reaction layer on the coating surface could effectively resist the penetration of the molten silicate.
Silicate material from environmental dust melts and adheres to the surfaces of thermal barrier coatings (TBCs) on hot-components of turbine engines accelerating their eventual failure. To mitigate against the wettability and spreadability of such molten deposits on TBCs, dual-scale structured (Gd0.9Yb0.1)2Zr2O7 TBCs with “lotus leaf” like surface morphology were fabricated using novel PS-PVD technology, which revealed an enhanced resistance to the wetting of molten silicate but experienced some degradation at high temperatures. By the ultrafast laser direct writing technology, the surface of the PS-PVD TBC was re-constructed, obtaining a triple-scale structure, consisting of conical micro-pillars, cauliflower-like domed micro-protuberances and nanoparticles. The contact angle of molten deposits at 1200 °C on this TBC was measured to be ∼ 127.2°, and after exposure to 1300 °C for 10 h, the TBC is still silicophobic (i.e., contact angle of ∼ 124.7°). This superior silicate phobicity is largely attributed to the increased surface roughness of the triple-scale structure. Further, the reaction layer appears to resist effectively further melt penetration. We thus propose that PS-PVD technology together with ultrafast laser direct writing may have great potential for the fabrication of molten silicophobic TBCs for turbine engines.
To comprehensively evaluate the effect of low birth weight on premature ovarian insufficiency.
We performed a systematic review of the literature by searching MEDLINE, EMBASE, Web of Science, Scopus, ...Wanfang and CNKI up to August 2023. All cohort and case-control studies that included birth weight as an exposure and premature ovarian insufficiency as an outcome were included in the analysis. Data were combined using inverse-variance weighted meta-analysis with fixed and random effects models and between-study heterogeneity evaluated. We evaluated risk of bias using the Newcastle Ottawa Scale and using Egger's method to test publication bias. All statistical analyses were performed with the use of R software.
Five articles were included in the review. A total of 2,248,594 women were included, including 21,813 (1%) cases of premature ovarian insufficiency, 150,743 cases of low birth weight, and 220,703 cases of macrosomia. We found strong evidence that changed the results of the previous review that low birth weight is associated with an increased risk of premature ovarian insufficiency (OR = 1.15, 95%CI 1.09-1.22) in adulthood compared with normal birth weight. No effect of macrosomia on premature ovarian insufficiency was found.
Our meta-analysis showed strong evidence of an association between low birth weight and premature ovarian insufficiency. We should reduce the occurrence of low birth weight by various methods to avoid the occurrence of premature ovarian insufficiency.
The accurate determination of the gas in place in shale reservoirs is a basic but challenging issue for shale gas evaluation. Conventional canister gas desorption tests on retrieved core samples and ...subsequent data analyses (via linear or polynomial regression)—originally developed for coalbed methane, where gases are mainly stored in the adsorbed phase—is unadvisable for shale gas, which is stored as an appreciable amount of free gas in shale reservoirs. In the present study, a mathematical model that simultaneously takes into account gas expansion, adsorption/desorption, and the gas flow in shale is proposed to simulate gas release from a core sample retrieved from the Lower Silurian Longmaxi Formation of the Fuling shale gas field, Sichuan Basin. The results indicate that, compared with the value of 2.11 m3/t rock estimated with the traditional United States Bureau of Mines (USBM) method, the total gas in place within the studied Longmaxi Shale estimated with our mathematical model under reservoir pressure conditions is up to 5.88 m3/t rock, which is more consistent with the result from the new volumetric approach based on Ambrose et al. According to our mathematical model, the content of free gas is 4.11 m3/t rock at true “time zero”, which accounts for 69.9% of the total gas. On the other hand, the lost gas portion is determined to be up to 4.88 m3/t rock (~85% of the total gas). These results suggest that the majority of the free shale gas is actually trapped within the pore space of the shale formation.
Biofilms that colonize on the surface of microplastics (MPs) in freshwaters may pose a potential health risk. This study examined factors that influence MP-associated biofilm growth, including ...polymer type, degree of weathering, and source water quality. Weathered MPs produced in-lab were employed in biofilm trials conducted on site using a passive flow-through system with raw water at drinking water treatment facility intakes. Adenosine triphosphate (ATP) was used to quantify biofilm abundance; biofilm composition was assessed via metagenomic sequencing. Biofilm growth was observed on all polymer types examined and most prevalent on polyvinyl chloride (PVC), where ATP levels were 6 to 12 times higher when compared to other polymers. Pathogen-containing species including Salmonella enterica and Escherichia coli were present on all polymers with relative abundance up to 13.7%.
was selectively enriched on weathered MPs in specific water matrices. These findings support the need to research the potential accumulation of pathogenic organisms on microplastic surfaces.
Two enamel coatings with a high and a low silica content were prepared on 35CrMo steels via vacuum firing. Their corrosion behavior in a 0.5 M HCl solution including corrosion kinetics, ...microstructures and electrochemistry performance were studied in comparison with uncoated steels. The results show that catastrophic corrosion occurred for uncoated steels while enamel coatings significantly decreased the corrosion rate. Enamel coatings with a high silica content exhibited the best corrosion resistance against hydrochloric acid due to their highly connected silicate network, which inhibited the leaching process of alkali metals in the acid solution. The corrosion inhibition efficiency for enamel containing a high silica content reached a maximum of 94.3%.
A (Gd0.8Yb0.2)2Zr2O7/YSZ double ceramic layer thermal barrier coating (TBC) system prepared by electron-beam physical vapor deposition (EB-PVD) is a promising choice for protecting hot-section parts ...of areo-plane gas-turbine engines at ultra-high temperature. The microstructure and further thermal cycling lifespan are strongly dependent on the EB-PVD process parameters (sample rotational speed, deposition temperature, chamber pressure, etc.). In the current study, three kinds of (Gd0.8Yb0.2)2Zr2O7/YSZ double ceramic layer TBCs were manufactured with different sample rotation speeds by EB-PVD. The thermal cycling behaviour of the three TBCs with different microstructures was investigated at 1150°C in comparison with the single YSZ-TBC. The results showed that TBCs prepared with low sample rotation speed were made of small and irregular columnar grains and exhibited the best thermal cycling behaviour among all the tested TBCs. The effect of sample rotation speed during deposition on microstructure and further thermal cycling behaviour, including crack evolution and TGO growth were discussed.
Several studies have reported positive therapeutic effects of electroacupuncture, warm needling, or a combination of the 2 for heel pain; however, the quality of the evidence is limited by ...methodological limitations. Given that there are no high-quality meta-analyses or reviews incorporating the available evidence, the aim of this study was to systematically review the level I evidence in the literature to determine whether a combination of electroacupuncture and warm needling therapy is more beneficial than acupuncture alone in patients with plantar heel pain syndrome.
From the inception to May 2022, the Wanfang, CNKI, EMBASE, PubMed, Web of Science, and Cochrane Library electronic databases will be searched using the key phrases "acupuncture", "warm needling", "electroacupuncture", "heel pain", "plantar pain", and "prospective" for all relevant studies. The outcomes include pain, physical disability, plantar fascia thickness, and foot functional status. Quality assessment of all studies included in this review will be independently assessed by 2 reviewers using the Cochrane Collaborations tool. We consider significant heterogeneity between trials if I2 > 50%, and severe heterogeneity if I2 > 75%. When significant heterogeneity is indicated, we will find the source of heterogeneity by subgroup or sensitivity analysis.
The results of our review will be reported strictly following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses reporting guidelines and the recommendations of the Cochrane Collaboration.
We initially hypothesized that combination therapy would lead to better treatment outcomes.Registration number: 10.17605/OSF.IO/VWBYJ.
Exposure of Ni–Cr alloys containing 5–30 wt% Cr to Ar-20O
2
and Ar-20O
2
-20H
2
O at 650 °C produced an external NiO layer, internal chromium oxidation and an intermediate zone of NiO + Cr
2
O
3
. ...The NiO layer growth rate decreased with increasing alloy Cr content. Addition of water vapor to dry O
2
changed the NiO grain structure from equiaxed-shaped to columnar-shaped. In pure water vapor, a thin external NiO layer was formed above a layer of unoxidized metallic Ni, with an IOZ beneath. Water vapor effects on NiO formation are discussed in terms of different mechanisms whereby the volume increase in the IOZ is accommodated.
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