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Most methanotrophs produce Mb to facilitate copper uptake, maintain Cu homeostasis, and protect against the toxic effects of high Cu concentration ( I M. trichosporium i OB3b on 10 µM Cu) [[98]]. The chelation of copper forms the Cu-Mb complex, which is a copper uptaking strategy of MOB in copper-limited conditions [[97]]. In the culture of I Methylococcus capsulatus i Bath, pMMO facilitates CH SB 4 sb oxidation in the cytoplasm when Cu/cell ratios are high (increased from 0 to 55 µM of Cu), while sMMO is activated in the periplasmic membrane space when Cu/cell ratios are low (decreased to 0 µM of Cu) because of different expression patterns (see above). Keywords: ammonia and methane oxidation; monooxygenase; copper; iron; methanobactin; siderophore EN ammonia and methane oxidation monooxygenase copper iron methanobactin siderophore 1806 18 11/17/22 20221101 NES 221101 1. On the other hand, Cu-chelating Mb also played a critical role in maintaining Cu homeostasis and protection against the potentially toxic effects of a high Cu concentration ( I M. trichosporium i OB3b on 10 µM copper) (see Figure 2) [[98]]. [Extracted from the article]

This study proposes an electromagnetic shielding material sprayed with silver-coated copper powder (core-shell powder). The shielding properties of the material are analyzed in details section. Cross-sectional observation and sheet resistance measurement were used to determine the thickness and electrical conductivity of the electromagnetic shielding layer, which was generated by spray-coating; this aided in confirming the uniformity of the coating film. The results indicate that the electromagnetic interference shielding effectiveness increases when the silver-coated copper paste (core-shell paste) is used as the coating material rather than the conventional aluminum base. The proposed material can be used in various frequency ranges owing to the excellent shielding effectiveness of the core-shell paste used in this study. Further investigations on the optimized spray-coating type of electromagnetic shielding material are required based on the composition of the core-shell paste and the thickness of the coating film. [ABSTRACT FROM AUTHOR]

We investigate the copper-wear-protective effects of graphene and boron nitride in single asperity sliding contact with a stiff diamond-coated atomic force microscopy (AFM)-tip. We find that both graphene and boron nitride retard the onset of wear of copper. The retardment of wear is larger with boron nitride than with graphene, which we explain based on their respective out-of-plane stiffnesses. The wear protective effect of boron nitride comes, however, at a price. The out-of-plane stiffness of two-dimensional materials also determines their friction coefficient in a wear-less friction regime. In this regime, a higher out-of-plane stiffness results in larger friction forces. [ABSTRACT FROM AUTHOR]

To analyze the reinforcement effect of adding polymer to solder paste, epoxies were mixed with two currently available Sn-3.0Ag-0.5Cu (wt.% SAC305) and Sn-59Bi (wt.%) solder pastes and specimens prepared by bonding chip resistors to a printed circuit board. The effect of repetitive thermal stress on the solder joints was then analyzed experimentally using thermal shock testing (−40 °C to 125 °C) over 2000 cycles. The viscoplastic stress–strain curves generated in the solder were simulated using finite element analysis, and the hysteresis loop was calculated. The growth and propagation of cracks in the solder were also predicted using strain energy formulas. It was confirmed that the epoxy paste dispersed the stress inside the solder joint by externally supporting the solder fillet, and crack formation was suppressed, improving the lifetime of the solder joint. [ABSTRACT FROM AUTHOR]

This study investigated the suppression of the growth of the intermetallic compound (IMC) layer that forms between epoxy solder joints and the substrate in electronic packaging by adding graphene nano-sheets (GNSs) to 96.5Sn–3.0Ag–0.5Cu (wt %, SAC305) solder whose bonding characteristics had been strengthened with a polymer. IMC growth was induced in isothermal aging tests at 150 °C, 125 °C and 85 °C for 504 h (21 days). Activation energies were calculated based on the IMC layer thickness, temperature, and time. The activation energy required for the formation of IMCs was 45.5 KJ/mol for the plain epoxy solder, 52.8 KJ/mol for the 0.01%-GNS solder, 62.5 KJ/mol for the 0.05%-GNS solder, and 68.7 KJ/mol for the 0.1%-GNS solder. Thus, the preventive effects were higher for increasing concentrations of GNS in the epoxy solder. In addition, shear tests were employed on the solder joints to analyze the relationship between the addition of GNSs and the bonding characteristics of the solder joints. It was found that the addition of GNSs to epoxy solder weakened the bonding characteristics of the solder, but not critically so because the shear force was higher than for normal solder (i.e., without the addition of epoxy). Thus, the addition of a small amount of GNSs to epoxy solder can suppress the formation of an IMC layer during isothermal aging without significantly weakening the bonding characteristics of the epoxy solder paste. [ABSTRACT FROM AUTHOR]

Inflammatory-related diseases are becoming increasingly prevalent, leading to a growing focus on the development of anti-inflammatory agents, with a particular emphasis on creating novel structural compounds. In this study, we present a highly efficient synthetic method for direct N-arylation to produce a variety of N(2)-arylindazol-3(2H)-ones 3, which exhibit anti-inflammatory activity. The Chan–Evans–Lam (CEL) coupling of N(1)-benzyl-indazol-3-(2H)-ones 1 with arylboronic acids 2 in the presence of a copper complex provided the corresponding N(2)-arylindazol-3(2H)-ones 3 in good-to-excellent yields, as identified with NMR, MS, and X-ray crystallography techniques. The cell viability and anti-inflammatory effects of the synthesized compounds (3 and 5) were briefly assessed using the MTT method and Griess assay. Among them, compounds 5 exhibited significant anti-inflammatory effects with negligible cell toxicity. [ABSTRACT FROM AUTHOR]