Anthranilamide-protected vinylboronic acid: rational monomer design for improved polymerization/transformation ability providing access to conventionally inaccessible copolymers

We have studied several protecting groups for vinylboronic-acid derivatives as monomers in radical polymerizations with the objective to improve the polymerization ability and C–B bond-cleaving post-transformation performance. Anthranilamide (aam)-protected vinylboronic acid (VBaam) exhibited experimentally a relatively high polymerization activity, which was theoretically corroborated by density functional theory (DFT) calculations that revealed a peculiar effect of the interaction between the aam groups on the polymerization behavior. The VBaam units in the copolymers can subsequently be transformed into vinyl alcohols or into ethylene units through C–B-bond-cleaving side-chain replacement, which affords valuable copolymers such as poly(vinyl alcohol-co-styrene), poly(ethylene-co-styrene), and poly(ethylene-co-acrylate)

Strength-enhanced Sn–In low-temperature alloy with surface-modified ZrO₂ nanoparticle addition

Low-temperature packaging is essential for the widespread use of flexible electronic devices, and Sn–In eutectic alloys have attracted considerable attention because of their low melting temperatures. However, these alloys have a lower strength compared with other types of solder alloys. This study aimed to investigate the effect of adding nanoparticles on the mechanical strength of Sn–In eutectic alloys while keeping their melting temperature unchanged. ZrO₂ nanoparticles coated with NiO (NiO/ZrO₂ nanoparticles) were utilized to strengthen Sn–In eutectic alloys with a high dispersity. Sn–In composite alloys reinforced with NiO/ZrO₂ nanoparticles were fabricated, and tensile strength evaluation and microstructure observations were conducted. The experimental results showed that the addition of nanoparticles to the Sn–In eutectic alloys did not change their melting behavior. The tensile strength of the Sn–In composite alloys reinforced with NiO/ZrO₂ nanoparticles increased by up to 35.6%, which was attributed to grain refinement and dispersion strengthening. Even after thermal aging at 60 ºC, the Sn–In composite alloys reinforced with NiO/ZrO₂ nanoparticles showed a 1.11 times higher ultimate tensile strength than that of the non-aged, non-reinforced eutectic alloy, despite grain coarsening. This was attributed to the contribution of dispersion strengthening. These results indicate that the addition of NiO/ZrO₂ nanoparticles is an effective method to improve the strength of low-melting-temperature alloys.The version of record of this article, first published in Journal of Materials Science: Materials in Electronics, is available online at Publisher’s website: https://doi.org/10.1007/s10854-023-11344-

Enhancement of Au Dissolution by Microorganisms Using an Accelerating Cathode Reaction

『大阪大学大学院工学研究科環境・エネルギー工学専攻生物圏環境工学領域 研究活動報告』, (2008.4.1～2009.3.31), pp.132～137, 大阪大学大学院工学研究科環境・エネルギー工学専攻環境資源・材料学講座生物圏環境工学領域, 2009.5 に掲

Information-seeking behaviour of community pharmacists during the COVID-19 pandemic: an ecological study

[Objective] To evaluate the information-seeking behaviour of pharmacists during the COVID-19 pandemic and its relation to COVID-19 and related infections and deaths within the local prefecture. [Design] Ecological study. [Setting] Japan—47 prefectures. [Methods] The number of accesses to a Japanese web page established by the Pharmacy Informatics Group to disseminate information about infection control and the number of infections and deaths in 47 prefectures were investigated from 6 April to 30 September 2020 using the access information on the web page and publicly available information. [Results] During the first 6 months of the COVID-19 pandemic, the total number of accesses was 226 130 (range: 10 984–138 898 per month), the total number of infections was 78 761 (1738–31 857) and the total number of deaths was 1470 (39–436). The correlation between the total number of accesses and that of infections per 100 000 individuals in 47 prefectures was r=0.72 (95% CI 0.55 to 0.83, p<0.001), and between the total number of accesses and deaths per 100 000 individuals in 47 prefectures was r=0.44 (95% CI 0.17 to 0.65, p=0.002). [Conclusions] The information-seeking behaviour of community pharmacists correlated positively with infection status within the community

Impact of crystalline orientation on Cu–Cu solid-state bonding behavior by molecular dynamics simulations

Tatsumi H., Kao C.R., Nishikawa H.. Impact of crystalline orientation on Cu–Cu solid-state bonding behavior by molecular dynamics simulations. Scientific Reports 13, 23030 (2023); https://doi.org/10.1038/S41598-023-50427-3.High-density electronics are hindered by the constraints of Sn-based solder joints, necessitating the exploration of Cu–Cu solid-state bonding. However, current bonding methods are expensive and time-consuming; therefore, understanding the Cu–Cu bonding mechanism is crucial for optimization. This study utilizes molecular dynamics (MD) simulation to elucidate the Cu–Cu solid-state bonding behavior, focusing on interfacial densification and diffusion phenomena. Furthermore, it highlights the influence of crystal orientation on the interfacial bonding behavior. To analyze the impact of crystal orientation, monocrystalline Cu slabs with a simplified periodic surface structure were employed to replicate surface roughness and subsequently bonded at a specific temperature. The results indicate the critical influence of crystalline orientations on the bonding process: identical orientations result in slower densification at the interface, whereas misoriented orientations significantly accelerate it. This effect, attributed to the grain boundary (GB) structures formed owing to misorientation, suggests a central role for GB diffusion in bonding progression. Diffusion coefficients calculated using the mean square displacement (MSD) confirmed these findings and exhibited significantly larger values for misoriented joints. Additionally, the simulations reveal an activation energy for GB diffusion that is lower than conventional values, highlighting the impact of the crystallographic orientation and voids at the bonding interface. Our research elucidates the role of crystalline orientation in diffusion phenomena at bonding interfaces, offering valuable implications for optimizing bonding-based manufacturing processes

Biotransformation of Bisphenol A and Its Adverse Effects on the Next Generation

Although we are exposed to many chemical substances in routine daily life, the body has metabolic systems capable of detoxifying and eliminating these chemicals. Bisphenol A (BPA) is an endocrine disrupter of great concern because of its estrogenic activity, but studies have indicated no severe adverse effects in adult rodents exposed to BPA due to metabolic detoxification. BPA is metabolized by glucuronidation mediated by phase II enzymes such as UDP-glucuronosyltransferase. Numerous recent studies in rodents have indicated that maternal BPA exposure causes adverse effects in offspring. It was also shown that bisphenol analogs are efficiently absorbed via the oral route and distributed to the reproductive tract in pregnant rats, with its residue capable of crossing the placental barrier in the late stage of gestation. Both animal and human studies have demonstrated that BPA and the BPA metabolite BPA-GA are detectable in fetal and amniotic fluid, suggesting the presence of a placental transfer mechanism. In this review, we discuss the pharmacokinetics of BPA, particularly its (1) metabolism and disposition in the intestine, (2) metabolism and disposition in the liver, and (3) transfer from maternal tissues to the fetus