A facile synthesis of bromodifluoromethylated selenides under metal-free conditions is described here. Commercially available Me
SiCF
Br and bench-stable selenosulfonates react smoothly to give a ...broad scope of alkyl- and aryl-substituted bromodifluoromethylated selenides in moderate to good yields via a difluorocarbene intermediate. This protocol features a short reaction time, the absence of toxic waste, good scalability, and successful late-stage modification of bioactive molecules. In addition, the title products can be easily converted to different fluorinated and
F-labeled selenides.
The ungenerous release of metals from different industrial, agricultural, and anthropogenic sources has resulted in heavy metal pollution. Metals with a density larger than 5 g cm
−3
have been termed ...as heavy metals and have been stated to be potentially toxic to human and animals. Algae are known to be pioneer organisms with the potential to grow under extreme conditions including heavy metal-polluted sites. They have evolved efficient defense strategies to combat the toxic effects exerted by heavy metal ions. Most of the algal strains are reported to accumulate elevated metal ion concentration in cellular organelles. With respect to that, this review focuses on understanding the various strategies used by algal system for heavy metal resistance. Additionally, the application of this metal resistance in biosynthesis of metal nanoparticles and metal oxide nanoparticles has been investigated in details. We thereby conclude that algae serve as an excellent system for understanding metal uptake and accumulation. This thereby assists in the design and development of low-cost approaches for large-scale synthesis of nanoparticles and bioremediation approach, providing ample opportunities for future work.
Rare Earth Frontiers is a work of human geography that serves to demystify the powerful elements that make possible the miniaturization of electronics, green energy and medical technologies, and ...essential telecommunications and defense systems. Julie Michelle Klinger draws attention to the fact that the rare earths we rely on most are as common as copper or lead, and this means the implications of their extraction are global. Klinger excavates the rich historical origins and ongoing ramifications of the quest to mine rare earths in ever more impossible places. Klinger writes about the devastating damage to lives and the environment caused by the exploitation of rare earths. She demonstrates in human terms how scarcity myths have been conscripted into diverse geopolitical campaigns that use rare earth mining as a pretext to capture spaces that have historically fallen beyond the grasp of centralized power. These include legally and logistically forbidding locations in the Amazon, Greenland, and Afghanistan, and on the Moon. Drawing on ethnographic, archival, and interview data gathered in local languages and offering possible solutions to the problems it documents, this book examines the production of the rare earth frontier as a place, a concept, and a zone of contestation, sacrifice, and transformation.
The cover image is based on the Original Article Characteristics, distribution, and children exposure assessment of 13 metals in household dust in China: A big data pilot study by Xu Li et al., ...https://doi.org/10.1111/ina.12943.
Understanding the thermal aggregation behavior of metal atoms is important for the synthesis of supported metal clusters. Here, derived from a metal–organic framework encapsulating a trinuclear ...FeIII2FeII complex (denoted as Fe3) within the channels, a well‐defined nitrogen‐doped carbon layer is fabricated as an ideal support for stabilizing the generated iron nanoclusters. Atomic replacement of FeII by other metal(II) ions (e.g., ZnII/CoII) via synthesizing isostructural trinuclear‐complex precursors (Fe2Zn/Fe2Co), namely the “heteroatom modulator approach”, is inhibiting the aggregation of Fe atoms toward nanoclusters with formation of a stable iron dimer in an optimal metal–nitrogen moiety, clearly identified by direct transmission electron microscopy and X‐ray absorption fine structure analysis. The supported iron dimer, serving as cooperative metal–metal site, acts as efficient oxygen evolution catalyst. Our findings offer an atomic insight to guide the future design of ultrasmall metal clusters bearing outstanding catalytic capabilities.
Encapsulation of a trinuclear FeIII2FeII complex within channels of a unique MOF is leading to the generation of iron nanoclusters stabilized on the carbon layer. To inhibit the aggregation of iron atoms toward nanoclusters, a “heteroatom modulator approach” is developed by atomic replacement of FeII by ZnII/CoII. A stable iron dimer in an optimal metal–nitrogen moiety is synthesized as efficient oxygen evolution catalyst.
Health implications to the population due to the consumption of contaminated vegetables has been a great concern all over the world. In this study, the levels of heavy metals (Cr, Cd, Zn, Fe, Pb, As, ...Mn, Cu, Hg, Ni and Co) in soil and commonly consumed vegetables from Mojo area in central Ethiopia have been determined using Inductively Coupled Plasma Optical Emission Spectrophotometer (ICP-OES) and possible health risks due to the consumptions of the vegetables have also been estimated. The levels of As, Pb, Cd, Zn, Cu, Hg and Co were exceeded the reference level in agricultural soil. Likewise, As, Pb, Cd, Cr and Hg levels exceeded the recommended values in vegetable samples with concentrations ranging from 1.93-5.73, 3.63-7.56, 0.56-1.56, 1.49-4.63 and 3.43-4.23 mg/kg, respectively. It was observed that leafy vegetable (cabbage) has accumulated heavy metals to greater extent compared with tomato. The estimated daily intake (EDI) of toxic metals due to the consumption of the vegetables were below the maximum tolerable daily intake (MTDI). However, the total health quotient (THQ), calculated based on EDI of the heavy metals were found > 1 for As and Hg due to tomato consumption and for As, Hg and Co due to cabbage consumption, suggesting significant health risk. The health index (HI) due to the intake of toxic metals from the consumption of both vegetables were much > 1, with HI values of 7.205 and 15.078 due to tomato and cabbage consumption, respectively. This clearly suggests the possible adverse health effect to adult population from the consumption of tomato and cabbage from the study area. The total cancer risk (TCR) analysis have also revealed the potential adverse cancer risk induced by As, Cd, Hg, and Ni from the consumption of both tomato and cabbage as their TCR values were above the threshold level. Based on the results of this study, there would be a significant health risk (both non-carcinogenic and carcinogenic) to the consumer associated with the consumption of cabbage and tomato being cultivated in Mojo area. Consequently, we recommend a strict regulatory control on the safety of vegetables originated from the study area.
Designing definite metal‐support interfacial bond is an effective strategy for optimizing the intrinsic activity of noble metals, but rather challenging. Herein, a series of quantum‐sized metal ...nanoparticles (NPs) anchored on nickel metal–organic framework nanohybrids (M@Ni‐MOF, M=Ru, Ir, Pd) are rationally developed through a spontaneous redox strategy. The metal‐oxygen bonds between the NPs and Ni‐MOF guarantee structural stability and sufficient exposure of the surface active sites. More importantly, such precise interfacial feature can effectively modulate the electronic structure of hybrids through the charge transfer of the formed Ni‐O‐M bridge and then improves the reaction kinetics. As a result, the representative Ru@Ni‐MOF exhibits excellent hydrogen evolution reaction (HER) activity at all pH values, even superior to commercial Pt/C and recent noble‐metal catalysts. Theoretical calculations deepen the mechanism understanding of the superior HER performance of Ru@Ni‐MOF through the optimized adsorption free energies of water and hydrogen due to the interfacial‐bond‐induced electron redistribution.
A facile and spontaneous strategy is presented for synthesizing Ru‐nanoparticle‐anchored metal–organic framework nanohybrids on Ni foam. The nanohybrids exhibit excellent HER performance at all pH values owing to the optimized adsorption free energies of intermediates by the interfacial‐bond‐induced electron redistribution.
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