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Gas evolution is fundamentally problematic in rechargeable batteries, and may lead to swelling, smoking, and device‐level failure. In laboratories, monitoring gas evolution can help understand dynamic chemical events inside battery cells, such as the formation of solid‐electrolyte interphases, structural change of electrodes, and electrolyte degradation reactions. However, gassing in commercial batteries, discrete or continuous, is not monitored due to a lack of compatible sensing technologies. Here we describe the working principles of four real‐time gas monitoring technologies for lithium‐ion batteries. Gassing mechanisms and reaction pathways of five major gaseous species, namely H2, C2H4, CO, CO2, and O2, are comprehensively summarized. Since pertinent progress has been made on the optical fiber‐based sensing of strain, pressure, and temperature of various battery cells recently, special emphasis has been given to fiber‐based laser spectroscopy for gas detection. The technical details of the fiber‐enhanced photothermal spectroscopy are compared with the four gas sensing technologies, and the commercialization possibilities are discussed. Owing to its small size, flexibility, and robustness, fiber‐based sensing technology can be compatible with almost all kinds of battery cells, showcasing their great potential in various applications. It is envisioned that gas‐event monitoring of rechargeable cells can be unlocked soon by utilizing fiber‐based gas spectroscopy. [ABSTRACT FROM AUTHOR]

3-R-1,4,2-dioxazol-5-ones are a class of compounds that are increasingly finding diverse uses, including as regioselective amidation reagents and as electrolyte additives that enable long cycling lifetimes in rechargeable lithium-ion batteries. Conventional methods for their synthesis tend to be slow and time-consuming, requiring isolation and thorough drying of a hydroxamic acid intermediate, followed by a separate cyclization step with N,N'-carbonyldiimidazole. Furthermore, the cyclization is typically performed in dichloromethane, an environmentally harmful solvent. This work demonstrates a new one-pot method for the synthesis of these compounds that eliminates the need for isolation of the intermediate or the use of halogenated solvents. The reaction is mainly performed using environmentally benign ethyl acetate and a relatively small amount of N,N-dimethylformamide. The reaction proceeds readily at room temperature and requires no expensive metal catalysts to function. Key words: dioxazolone, amidation, lithium-ion, electrolyte additive. Les 3-R-1,4,2-dioxazol-5-ones constituent une classe de composes de plus en plus utilises dans diverses applications, notamment comme reactifs d'amidation regioselective et comme additifs electrolytiques permettant d'augmenter le nombre de cycles de charge et de prolonger la duree de vie des batteries rechargeables au lithium-ion. Les methodes classiques de synthese de ces composes sont souvent lentes et chronophages. Elles requierent des etapes d'isolation et de sechage complet d'un acide hydroxamique intermediaire, suivies d'une etape de cyclisation a l'aide du N,N'-carbonyldiimidazole. De plus, la cyclisation est habituellement effectuee dans le dichloromethane, un solvant nocif pour l'environnement. Dans ces travaux, nous presentons une nouvelle methode de synthese monotope de ces composes qui permet d'eliminer a la fois la necessite d'isoler l'intermediaire et l'emploi de solvants halogenes. La reaction requiert l'emploi de matieres peu nocives pour l'environnement, principalement de l'acetate d'ethyle et une quantite relativement faible de N,N-dimethylformamide. Elle s'effectue rapidement a temperature ambiante et ne necessite aucun catalyseur metallique couteux pour fonctionner. [Traduit par la Redaction] Mots-cles : dioxazolone, amidation, lithium-ion, additif electrolytique., Introduction In recent years, 3-R-1,4,2-dioxazol-5-one compounds are increasingly finding use as versatile reagents, especially for regioselective C-H amidation ortho to a directing group on aromatic moieties. (1) These reagents act [...]

Investigated the effects of aggressor's and victim's sex on judgments regarding sexual aggression on dates. College students read vignettes describing dating aggression, rating degree of disapproval of aggressors' behaviors from their own, the aggressor's, and the victim's viewpoint. The effect of participant viewpoint in rating aggressor behavior was strong. Students disapproved of sexual aggressors in all types of couples. (SM)

This Resource Letter provides a guide to the literature on Bose-Einstein condensation in trapped dilute gases. Journal articles and books are cited for the following topics: history, technological advances, condensates as quantum fluids, effects of interatomic interactions, condensates as matter waves, condensate optics, multiple condensates, lower dimensions, spectroscopy and precision measurement, entanglement, and cosmology. [DOI: 10.1119/1.1569936]

An experimental protocol is developed to measure the shear strength of NMC811 single crystals within the cathode of a lithium-ion cell. The cathode is placed upon a set of thick metallic substrates that possess a wide range of indentation hardness. For each choice of substrate, the top surface of the cathode is indented by a Vickers indenter to a sufficient depth that the cathode layer is subjected to an approximately spatially uniform compressive normal traction equal to the hardness of the substrate. The sensitivity of plastic flow and fracture of the single crystals to substrate hardness is determined by observation of the particles in the indented top surface of the cathode using a scanning electron microscope. It is found that the shear strength of fully lithiated NMC811 single crystals along their basal plane is 86 ± 12 MPa, and decreases to 39 ± 5 MPa upon cell charging (delithiation of the cathode). This implies that particle slip and fracture will occur under mild mechanical loading, for example by calendering during manufacture and by electrical cycling of the compacted cathode. The indentation protocol developed here has application to a wide range of single crystal cathode materials. [ABSTRACT FROM AUTHOR]

More Than Two Franklin Veaux and Eve Rickert Thorntree Press [ILLUSTRATION OMITTED] Over the past few years I have reviewed several new books on Polyamory. Each one had something to [...]

The electrolyte additive lithium difluorophosphate improves the lifetime of lithium-ion cells. This work presents the synthesis and evaluation of alternative difluorophosphate salt electrolyte additives. Ammonium difluorophosphate is readily prepared via a solidstate, benchtop reaction of ammonium fluoride and phosphorus pentoxide that requires only gentle heating to initiate. The best yield of sodium difluorophosphate (NaFO) in the present study was obtained by reacting difluorophosphoric acid and sodium carbonate in 1,2-diemethoxyethane over 3 Å molecular sieves. Tetramethylammonium difluorophosphate was prepared from NaFO via cation-exchange with tetramethylammonium chloride. NaFO is here reported to be a very good electrolyte additive, with similar performance in NMC532/graphite pouch cells as the lithium salt. The beneficial nature of both additives is attributable to the difluorophosphate anion. In contrast, ammonium and tetramethylammonium difluorophosphates are found to be poor electrolyte additives. For the former, this is suggested to be due to the formation of lithium nitride and hydrogen gas. [ABSTRACT FROM AUTHOR]

Finding new electrolyte additives could help create lithium-ion batteries with better performance at high voltage, allowing higher energy density. However, finding the perfect additive remains a tremendous challenge, since researchers still don't understand how to predict their performance. A new group of dioxazolone electrolyte additives have been tested in lithium-ion batteries alone or in combination with well-known co-additives. The new additives consist of a 3-phenyl-1,4,2-dioxazol-5-one (PDO) parent structure with or without (methoxy, fluoro and nitro) functional groups on the para position of the phenyl ring. It is found that PDO (no functional group) and p-(4-nitrophenyl)-1,4,2-dioxazol-5-one (pNDO) are the best performing dioxazolones overall and show promising results. [ABSTRACT FROM AUTHOR]

The Jealousy Workbook: Exercises and Insights for Managing Open Relationships Kathy Labriola 2013, Greenery Press, 200 pages This useful paperback has just arrived as part of the expanding literature on [...]

an intimate life sex, love, and my journey as a surrogate partner Cheryl T. Cohen Greeene with Lorna Garano Soft Scull Press 2012 233 pages of text plus bibliography $11.51 [...]

GUIDE TO GETTING IT ON, 7th ed. Paul Joannides Goofy Foot Press 2013 1184 pages including glossary and index. This is a birth announcement of the latest edition of the [...]

SEX & GOD How Religion Distorts Sexuality Darrel Ray, Ed.D. IPC Press, Bonner Springs, KS 2012 279 pages plus bibliography and index Paperback $10.85 As this Journal's publisher, I receive [...]

The Myth of Sex Addiction David J. Ley, Ph.D. Rowman & Littlefield Publishers 2012 216 pages of text plus endnotes, bibliography and index, $30.89 I cannot stress enough how important [...]

This DVD takes you back to the early 70's through the eyes of Deanna and Paul, a formerly married couple and part of a four person group marriage, 40 years [...]

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Matt and Khym: Better Than Ever A film by Tony Comstock DVD running time 53 minutes plus extras comstockfilms.com [ILLUSTRATION OMITTED] I began my education in sex, like many, by [...]

Intersex (for lack of a better word) By Thea Hillman Manic D Press, 2008, 155 pages, $11.21 on Amazon [ILLUSTRATION OMITTED] As a sexuality educator, I have some familiarity with [...]

Opening Up: Creating and Sustaining Open Relationships Tristan Taormino Cleis Press, 2008, 290 pages [ILLUSTRATION OMITTED] I have had the opportunity to review a galley copy of Tristan's new book, [...]

Film Review: Do Communists Have Better Sex? A Film by Andre Meier First Run/Icarus Films http://www.frif.com/ 2006 (718-488-8900 or 800-876-1710) DVD, 52 minutes, color, in German with English subtitles [ILLUSTRATION [...]

State of 'The Union': Marriage and Free Love in the Late 1800s Sandra Ellen Schroer Routledge, New York, 2005 111 pages plus bibliography and index ISBN 0-415-97594-8 This small book, [...]

Why Marriage? The History Shaping Today's Debate Over Gay Equality George Chauncey Basic Books, Perseus Books Group, New York, 2004 189 Pages, $ 22.00 This book, by a University of [...]

The Clitoris: Forbidden Pleasure Directed by Stephen Firmin & Variety Moszynski First Run Icarus Films, 2003 This one hour video, produced by a multicultural group of people, openly discusses the [...]

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Electrolyte additives are a practical route to improving the lifetime and performance of lithium-ion cells. It is not well understood what makes a good additive; thus, the discovery of new additives poses a significant challenge. Computational methods have the potential to streamline the search for new additives, but it is important to compare predicted additive behavior with experimentally measured results. A new electrolyte additive, 1,3-dimethyl-2-imidazolidinone (DMI), has been evaluated in LiNi1-x-yMnxCoyO2 (NMC)/graphite pouch cells as a single additive and with the co-additive vinylene carbonate (VC). This work compares the density functional theory (DFT)-predicted behavior of DMI with experimental results, including differential capacity analysis (dQ/dV), electrochemical impedance spectroscopy (EIS), high-temperature storage, gas chromatography-mass spectrometry (GC-MS) and long-term cycling tests. The DFT-calculated reduction potential of DMI is −0.63 V vs Li/Li+, consistent with the experimental observation that it reduces at a lower potential than ethylene carbonate (EC), ∼0.80 V vs Li/Li+. Although DMI turns out not to be a competitively useful additive, the good match between many aspects of the experimental results and theoretical predictions is a good indication that it is possible to understand aspects of the behavior of additives. This can guide future researchers. [ABSTRACT FROM AUTHOR]