The effect of friction behavior on the migration of metal elements from stainless-steel articles for food contact

Objective To evaluate the effect of friction behavior on migration levels of metal elements from stainless-steel articles for food contact. Methods The migration levels of metal elements from used and new stainless-steel articles were compared according to GB 4806.9-2016 and Council of Europe Resolution CM/Res (2013) 9. The migration conditions were boiling in 4% acetic acid for 30 min followed by at room temperature for 24 h and soaking in 5 g/L citric acid at 100 ℃ for 2 h, respectively. Meanwhile, the impact of dynamic friction on migration were investigated on new stainless-steel articles, where the friction method were referred to the GB/T 32095.2-2015 standard. Migration of metal elements complied with the corresponding standard. Results Based on the European standard, migration of lead in the first migration test was above limit of quantitation (LOQ) in all five used stainless-steel articles after friction, but none in new ones. The quantification rate of chromium in the first migration test in 80% (4/5) of used stainless-steel articles were above LOQ after friction by GB 4806.9-2016 standard while were 20% (1/5) in new ones. The migration level of Cr was higher by GB 4806.9-2016 standard than by European resolution in single dynamic friction study. Results from the dynamic friction experiments indicated that the migration of Cr and Ni reached equilibrium after 3 times of friction. Conclusion The migration condition in GB 4806.9-2016 standard had stronger leaching ability for Cr from stainless-steel articles than that in European resolution. Friction behavior promoted corrosion and metal element migration of stainless steel. Long-term used stainless-steel products had higher lead and chromium migration than new products, but without safety risks

Characteristic Volatile Fingerprints and Odor Activity Values in Different Citrus-Tea by HS-GC-IMS and HS-SPME-GC-MS

Citrus tea is an emerging tea drink produced from tea and the pericarp of citrus, which consumers have increasingly favored due to its potential health effects and unique flavor. This study aimed to simultaneously combine the characteristic volatile fingerprints with the odor activity values (OAVs) of different citrus teas for the first time by headspace gas chromatography-ion mobility spectrometry (HS-GC-IMS) and headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS). Results showed that the establishment of a citrus tea flavor fingerprint based on HS-GC-IMS data can provide an effective means for the rapid identification and traceability of different citrus varieties. Moreover, 68 volatile compounds (OAV > 1) were identified by HS-SPME-GC-MS, which reflected the contribution of aroma compounds to the characteristic flavor of samples. Amongst them, the contribution of linalool with sweet flower fragrance was the highest. Odorants such as decanal, β-lonone, β-ionone, β-myrcene and D-limonene also contributed significantly to all samples. According to principal component analysis, the samples from different citrus teas were significantly separated. Visualization analysis based on Pearson correlation coefficients suggested that the correlation between key compounds was clarified. A comprehensive evaluation of the aroma of citrus tea will guide citrus tea flavor quality control and mass production

Base-Promoted Synthesis of β-Substituted-Tryptophans via a Simple and Convenient Three-Component Condensation of Nickel(II) Glycinate

A three-component reaction of nickel(II) glycinate was conducted for the convenient synthesis of β-substituted-tryptophans. The reaction worked smoothly under mild conditions and the procedure was simple and easy to handle

Comparative and Phylogenetic Analyses of Complete Chloroplast Genomes of <i>Scrophularia incisa</i> Complex (Scrophulariaceae)

The Scrophularia incisa complex is a group of closely related desert and steppe subshrubs that includes S. incisa, S. kiriloviana and S. dentata, which are the only S. sect. Caninae components found in Northwest China. Based on earlier molecular evidence, the species boundaries and phylogenetic relationships within this complex remain poorly resolved. Here, we characterized seven complete chloroplast genomes encompassing the representatives of the three taxa in the complex and one closely related species, S. integrifolia, as well as three other species of Scrophularia. Comparative genomic analyses indicated that the genomic structure, gene order and content were highly conserved among these eleven plastomes. Highly variable plastid regions and simple sequence repeats (SSRs) were identified. The robust and consistent phylogenetic relationships of the S. incisa complex were firstly constructed based on a total of 26 plastid genomes from Scrophulariaceae. Within the monophyletic complex, a S. kiriloviana individual from Pamirs Plateau was identified as the earliest diverging clade, followed by S. dentata from Tibet, while the remaining individuals of S. kiriloviana from the Tianshan Mountains and S. incisa from Qinghai–Gansu were clustered into sister clades. Our results evidently demonstrate the capability of plastid genomes to improve phylogenetic resolution and species delimitation, particularly among closely related species, and will promote the understanding of plastome evolution in Scrophularia

A comparative study on the oxidation state of lattice oxygen among Li1.14Ni0.136Co0.136Mn0.544O2, Li2MnO3, LiNi0.5Co0.2Mn0.3O2 and LiCoO2 for the initial charge-discharge

The Li-rich layered oxides are attractive electrode materials due to their high reversible specific capacity (>250 mA h g(-1)); however, the origin of their abnormal capacity is still ambiguous. In order to elucidate this curious anomaly, we compare the lattice oxygen oxidation states among the Li-rich layered oxide Li1.14Ni0.136Co0.136Mn0.544O2, Li2MnO3 and LiNi0.5Co0.2Mn0.3O2, the two components in Li-rich layered oxides, and the most common layered oxide LiCoO2 before and after initial charge-discharge. For simplicity, we employ chemical treatments of NO2BF4 and LiI acetonitrile solutions to simulate the electrochemical delithiation and lithiation processes. X-ray photoelectron spectroscopy (XPS) studies reveal that part of lattice oxygen in Li1.14Ni0.136Co0.136Mn0.544O2 and Li2MnO3 undergoes a reversible redox process (possibly O2- O-2(2-)), while this does not occur in LiNi0.5Co0.2Mn0.3O2 and LiCoO2. This indicates that the extra capacity of Li-rich layered oxides can be attributed to the reversible redox processes of oxygen in the Li2MnO3 component. Thermogravimetric analysis (TGA) further suggests that the formed O-2(2-) species in the delithiated Li1.14Ni0.136Co0.136Mn0.544O2 can decompose into O-2 at about 210 degrees C. This phenomenon demonstrates a competitive relationship between extra capacity and thermal stability, which presents a big challenge for the practical applications of these materials

Mechanisms of PANoptosis and relevant small-molecule compounds for fighting diseases

Abstract Pyroptosis, apoptosis, and necroptosis are mainly programmed cell death (PCD) pathways for host defense and homeostasis. PANoptosis is a newly distinct inflammatory PCD pathway that is uniquely regulated by multifaceted PANoptosome complexes and highlights significant crosstalk and coordination among pyroptosis (P), apoptosis (A), and/or necroptosis(N). Although some studies have focused on the possible role of PANpoptosis in diseases, the pathogenesis of PANoptosis is complex and underestimated. Furthermore, the progress of PANoptosis and related agonists or inhibitors in disorders has not yet been thoroughly discussed. In this perspective, we provide perspectives on PANoptosome and PANoptosis in the context of diverse pathological conditions and human diseases. The treatment targeting on PANoptosis is also summarized. In conclusion, PANoptosis is involved in plenty of disorders including but not limited to microbial infections, cancers, acute lung injury/acute respiratory distress syndrome (ALI/ARDS), ischemia-reperfusion, and organic failure. PANoptosis seems to be a double-edged sword in diverse conditions, as PANoptosis induces a negative impact on treatment and prognosis in disorders like COVID-19 and ALI/ARDS, while PANoptosis provides host protection from HSV1 or Francisella novicida infection, and kills cancer cells and suppresses tumor growth in colorectal cancer, adrenocortical carcinoma, and other cancers. Compounds and endogenous molecules focused on PANoptosis are promising therapeutic strategies, which can act on PANoptosomes-associated members to regulate PANoptosis. More researches on PANoptosis are needed to better understand the pathology of human conditions and develop better treatment

Lithium Bis(fluorosulfony)imide-Lithium Hexafluorophosphate Binary-Salt Electrolytes for Lithium-Ion Batteries: Aluminum Corrosion Behaviors and Electrochemical Properties

© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Aluminum corrosion behaviors and electrochemical properties of Lithium bis(fluorosulfony)imide (LiFSI)-lithium hexafluorophosphate (LiPF6) binary-salt electrolytes containing mixtures of LiFSI and LiPF6 (with a total salt content of 1.2 mol L−1) with different molar ratios in EC/EMC (3:7, by vol.) solutions are systematically investigated. Our experimental results from cyclic voltammetry, scanning electron microscopy (SEM), chronoamperometry and the charge-discharge measurements of Li/LiNi1/3Co1/3Mn1/3O2 half-cells demonstrate that the LiFSI-LiPF6 binary-salt electrolytes with the LiFSI concentrations lower than 0.3 mol L−1 exhibit not only passivating aluminum current collectors at 4.3 V vs. Li+/Li, but also improved cycling performance. Meanwhile, Artificial Graphite/LiNi1/3Co1/3Mn1/3O2 (AG/NMC111) pouch cells made with the LiFSI(0.2)-LiPF6 (1.0) electrolyte with the LiFSI concentration of 0.2 mol L−1 display an excellent cycling stability with 93.9% capacity retention at 1 C rate after 360 cycles, and enhanced capacity retention at −20 °C, 60 °C and after 55 °C storage for 30 days compared to cells with 1.2 mol L−1 LiPF6/EC-EMC conventional electrolyte. This work confirms that binary-salt electrolytes system, such as LiFSI-LiPF6, may be a promising method to enhance the longevity and storage properties of Li-ion batteries