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Abstract Magnesium isotopic compositions of evaporite deposits may record information concerning brine evolution during deposition. We report Mg isotopic values (δ26MgDSM3) measured from an evaporite deposit of langbeinite (K2Mg2(SO4)3) found in the Permian Salado Formation. We used these data to model Mg isotope fractionation between langbeinite and its parent brine. In addition, both measured and theoretical results are used to estimate precipitation temperature and interpret depositional environment. The Salado langbeinite δ26Mg values are relatively low and fall within a relatively narrow range (–4.12 ± 0.03‰ to −3.81 ± 0.07‰). Equilibrium fractionation factors between langbeinite and aqueous Mg2+ solutions were calculated using quantum chemical density functional theory. All computations were performed at the B3LYP/6‐31 + G(d,p) level. Solvation effects were addressed using a solvent model (“water‐droplet” approach) and mineral structures were investigated using volume variable cluster models (VVCM). The equilibrium Mg isotopic fractionation factors α between langbeinite and model brine solution we obtained are 1.0005, 1.0004, and 1.0003 (Δ26Mglangb‐water≈103lnα = 0.473‰, 0.390‰, and 0.322‰) at 10°C, 25°C, and 40°C, respectively. These relatively large equilibrium fractionation factors indicate significant Mg isotope fractionation between langbeinite and its parent brine during precipitation, as langbeinite preferentially incorporates the heavier 26Mg and 25Mg isotopes. Rayleigh distillation modeling of the Salado langbeinite's relatively light Mg isotopic composition requires δ26MgDSM3 values of −4‰ for the parent brine. Models favor a precipitation temperature as high as 40°C under equilibrium conditions. Potential disequilibrium precipitation conditions suggested by Mg isotopic data also imply rapid deposition in a hot, arid sedimentary environment prevailing in the southwestern U.S. during the Late Permian.

Background: Recent clinical trials have evaluated the efficacy of vonoprazan‐amoxicillin (VA) dual therapy as the first‐line treatment for Helicobacter pylori infection in different regions with inconsistent results reported. In this systematic review and meta‐analysis, we aimed to evaluate the efficacy of VA dual therapy compared to the currently recommended therapy for eradicating H. pylori. Materials and Methods: A comprehensive search of the PubMed, Cochrane, and Embase databases was performed using the following search terms: ("Helicobacter" OR "H. pylori" OR "Hp") AND ("vonoprazan" OR "potassium‐competitive acid blocker" OR "P‐CAB") AND ("amoxicillin" OR "penicillin") AND ("dual"). The primary outcome was to evaluate the eradication rate according to intention‐to‐treat and per‐protocol analysis. The secondary outcomes were adverse events and compliance. Results: A total of 15 studies involving 4, 568 patients were included. The pooled eradication rate of VA dual therapy was 85.0% and 90.0% by intention‐to‐treat and per‐protocol analysis, respectively. The adverse events rate and compliance of VA dual therapy were 17.5% and 96%, respectively. The efficacy of VA dual therapy was superior to proton pump inhibitors‐based triple therapy (82.0% vs. 71.4%, p < 0.01) but lower than vonoprazan‐containing quadruple therapy (83.1% vs. 93.3%, p = 0.02). 7‐day VA dual therapy showed lower eradication rates than 10‐day (χ2 = 24.09, p < 0.01) and 14‐day VA dual therapy (χ2 = 11.87, p < 0.01). The adverse events rate of VA dual therapy was lower than vonoprazan triple therapy (24.6% vs. 30.9%, p = 0.01) and bismuth‐containing quadruple therapy (20.5% vs. 47.9%, p < 0.01). No significant difference of compliance was observed between VA dual therapy and each subgroup. Conclusion: VA dual therapy, a novel regimen, showed high efficacy as the first‐line treatment for H. pylori eradication, which should be optimized before application in different regions. [ABSTRACT FROM AUTHOR]

In recent decades of research, organic coatings have been considered the most effective and economical measure for corrosion protection of metals. However, defects in organic coatings created during the curing reaction provide corrosion channels for corrosive media, which in turn accelerate the failure of metallic materials. Functional nanomaterials are considered to be the key to solving this challenge. Metal organic frameworks (MOFs) materials, as an emerging nanomaterial, show great potential as a durable and efficient nano-corrosion filler in organic anti-corrosion coatings. Therefore, this paper reviews the application of MOFs materials as solid corrosion inhibitors, small molecule corrosion inhibitor vehicles and modified graphene oxide in anti-corrosion coatings and looks forward to the prospect of research on their application in engineering practice. [ABSTRACT FROM AUTHOR]

Thermal ionization mass spectrometry is considered as the "gold standard" for obtaining precise 87Sr/86Sr isotopic ratios. However, the conventional TIMS technique is laborious because it requires the purification of Sr using expensive and complex resin column techniques to overcome severe 87Rb isobaric interference on 87Sr and inhibition on ionization of Sr originating from matrix elements. To overcome this issue, we have developed a hydrofluoric acid coprecipitation method specifically designed for red wine samples. This method effectively captures Sr while eliminating 87Rb isobaric interference and removing the majority of matrix element inhibition for red wine samples. Notably, our method offers several advantages, including low cost, rapidity, simplicity, and high sample throughput. We have applied this method to analyze nine red wine samples sourced from China, Spain, Chile, Argentina, France, Italy, and Australia. Our method greatly simplified the sample preparation process for red wine samples without compromising the analytical accuracy and precision. [ABSTRACT FROM AUTHOR]

Variable cross-section spherical groove structure had high surface hardness and complex 3D shape. ECM had better technical and economic advantages, but the processing accuracy and processing stability were affected by the flow field obviously. In order to improve the uniformity of the electrolyte flow field, the influences of the electrolyte flow mode and channel structure on the flow field distribution were discussed based on the flow field simulation analysis, and the ECM experiments were carried out. The simulation and test results show that the zonal liquid flow in directional channel is conducive to improving the stability of the flow field and the consistency of the flow rate distribution, which may improve the processing stability. Optimization of the inlet and outlet flow channel structures may further improve the surface quality of the spherical groove, which may meet the requirements of machining stability and machining accuracy. [ABSTRACT FROM AUTHOR]