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Lipoquinones are the topic of this review and are a class of hydrophobic lipid molecules with key biological functions that are linked to their structure, properties, and location within a biological membrane. Ubiquinones, plastoquinones, and menaquinones vary regarding their quinone headgroup, isoprenoid sidechain, properties, and biological functions, including the shuttling of electrons between membrane-bound protein complexes within the electron transport chain. Lipoquinones are highly hydrophobic molecules that are soluble in organic solvents and insoluble in aqueous solution, causing obstacles in water-based assays that measure their chemical properties, enzyme activities and effects on cell growth. Little is known about the location and ultimately movement of lipoquinones in the membrane, and these properties are topics described in this review. Computational studies are particularly abundant in the recent years in this area, and there is far less experimental evidence to verify the often conflicting interpretations and conclusions that result from computational studies of very different membrane model systems. Some recent experimental studies have described using truncated lipoquinone derivatives, such as ubiquinone-2 (UQ-2) and menaquinone-2 (MK-2), to investigate their conformation, their location in the membrane, and their biological function. Truncated lipoquinone derivatives are soluble in water-based assays, and hence can serve as excellent analogs for study even though they are more mobile in the membrane than the longer chain counterparts. In this review, we will discuss the properties, location in the membrane, and syntheses of three main classes of lipoquinones including truncated derivatives. Our goal is to highlight the importance of bridging the gap between experimental and computational methods and to incorporate properties-focused considerations when proposing future studies relating to the function of lipoquinones in membranes. [ABSTRACT FROM AUTHOR]

Recent advances in photovoltaic devices demonstrate a potential candidature of the lead halide perovskite solar cells (PSCs) to fulfill the all-electric future of the world. Further improvements in efficiency and stability require minimization of non-radiative recombination arising due to the tr ap states created by the vacancies and defects. The device’s performance is mostly determined by the perovskite absorber material, which has single-cation, mixed-cation, and/or mixed-halide composition-dependent optoelectronic capabilities. Herein, we present an insight on the state of the art of PSCs, including types of defects, their effects, and remedies of the same. Various design strategies administered to grow highly crystalline perovskite films with low defects at interfaces are described in detail. The inclusion of a few nm thin interlayer between perovskite and charge transport layer (CTL) is an effective way to passivate the defect at the interface. Furthermore, additive engineering is emerging as an excellent strategy to grow the defect-free perovskite by simply adding a polymer, ionic liquids, organic/inorganic salts in precursor solution without precipitating after film formation. The mitigation of charge recombination could be achieved by efficient charge extraction through proper energy alignment of CTLs and absorbers. Notably, we emphasize the interface, additive, and gradient band alignment engineering and resulting improvement in the photocurrent density, photovoltage, power conversion efficiency, and long-term stability. The present review gives complete information about PSCs, starting from the selection of the materials to PSC fabrication, charge carrier dynamics, defects, effects, and remedies. We hope that this summarised information will give a basic understanding of designing new passivation strategies for advancing PSC’s present state of the art. [ABSTRACT FROM AUTHOR]

Zirconolite (CaZrTi2O7) has been identified as a candidate ceramic wasteform for the immobilisation and disposal of Pu inventories, for which there is no foreseen future use. Here, we provide an overview of relevant zirconolite solid solution chemistry with respect to Ce, U and Pu incorporation, alongside a summary of the available literature on zirconolite aqueous durability. The zirconolite phase may accommodate a wide variety of tri- and tetravalent actinide and rare-earth dopants through isovalent and heterovalent solid solution, e.g. CaZr1–xPuxTi2O7 or Ca1–xPuxZrTi2–2xFe2xO7. The progressive incorporation of actinides within the zirconolite-2M parent structure is accommodated through the formation of zirconolite polytypoids, such as zirconolite-4M or 3T, depending on the choice of substitution regime and processing route. A variety of standardised durability tests have demonstrated that the zirconolite phase exhibits exceptional chemical durability, with release rates of constituent elements typically <10−5 gm−2·d−1. Further work is required to understand the extent to which polytype formation and surrogate choice influence the dissolution behaviour of zirconolite wasteforms. [ABSTRACT FROM AUTHOR]

The linear viscoelasticity of coacervates formed by oppositely charged polyelectrolytes in the salt solution is reviewed, with a focus on time-temperature, time-salt, time-pH, and time-hydration superpositions, and on fundamental relaxation mechanisms. A variety of polyelectrolyte pairs are covered, showing the frequent, but not universal, success of the time-salt superposition. Master curves in many cases are similar to those for neutral polymers, including Rouse and reptation theories. However, in some cases, solidlike, as opposed to fluidlike, response is observed at low frequencies, especially at low salt concentrations. Some coacervates seem to fit "sticky diffusion" theory reasonably well, wherein relaxation is controlled by the breakage rate of ion pairs; the dependence of the "sticker" lifetime on salt concentration has been explored but is not well understood as yet. It is also possible that local relaxation is not controlled by breakage of ion pairs but by cooperative, "glassy," relaxation of monomers, salt ions, and water molecules. Compilation and comparison of different datasets and suggested formulas for rheological time constants are presented, and some suggestions are given for future directions. [ABSTRACT FROM AUTHOR]

Bisphenols have drawn increasing attention from regulatory agencies and scientific communities due to their widespread occurrences, distribution and endocrine disrupting effects, and severe toxicity. As one of the bisphenol A (BPA) substitutes, bisphenol S (BPS) is most frequently detected in the environment. Although numerous studies have shown its occurrence, distribution, and toxicity to certain aquatic species, investigation on BPS removal from aqueous environments is lacking. Thus, in this review, we summarize the state-of-art about BPS removal approaches including biodegradation, sorption, and advanced oxidation processes. Particular attention has been paid to the BPS sorption mechanisms, active species for BPS biodegradation, and the corresponding degradation pathways. The primary degradation intermediates formed during BPS oxidation (e.g. p-hydroxybenzenesulfonic acid) are discussed. The effects of solution chemistry (pH, ionic strength, anion, and surfactants) on BPS decontamination are also emphasized. In addition, knowledge gaps, current challenges, and future research needs of BPS decontamination in real environments have been discussed briefly. Through this review we demonstrate the overarching scientific opportunities for a comprehensive understanding of the efficiency and mechanisms of the bio-and chemical remediation approaches of BPS contaminated water. Microplastics may become a new source of bisphenol S (BPS) in aquatic environment. BPS is biodegradable but it may take a long time. Major mechanisms for BPS sorption are summarized and discussed. BPS degradation mechanisms and pathways are summarized. [ABSTRACT FROM AUTHOR]

This is a delightful little book that captures many of the beauties of hydrogen bonding for high school and early college-going students, and yet it touches on some fairly advanced concepts. Armed with the chemical background in the early part of the book, it would not be difficult for a reader to appreciate that the hydrogen atom in chloroform is activated enough to function as a hydrogen bond donor. A good book triggers off many streams of thought in the mind of the reader and apart from young students of science who would really benefit from "The Hydrogen Bond. [Extracted from the article]

Reviews the book 'Electrochemistry in Aqueous Solutions,' by Kosuke Izutsu.

Reviews the book 'Liquids and Solutions: Structure and Dynamics,' by P. Kruus.

The article reviews the book "Handbook of Green Chemistry: Set III: Green Solvents," edited by Walter Leitner, Philip G. Jessop, Chao-Jun Li, Peter Wasserscheid, Annegret Stark, and Paul T. Anastas.

The article reviews the book "The aqueous chemistry of the elements," by George K. Schweitzer and Lester L. Pesterfield.