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The solid-electrolyte interphase (SEI) plays crucial roles for the reversible operation of lithium metal batteries. However, fundamental understanding of the mechanisms of SEI formation and evolution is still limited. Herein, we develop a depth-sensitive plasmon-enhanced Raman spectroscopy (DS-PERS) method to enable in-situ and nondestructive characterization of the nanostructure and chemistry of SEI, based on synergistic enhancements of localized surface plasmons from nanostructured Cu, shell-isolated Au nanoparticles and Li deposits at different depths. We monitor the sequential formation of SEI in both ether-based and carbonate-based dual-salt electrolytes on a Cu current collector and then on freshly deposited Li, with dramatic chemical reconstruction. The molecular-level insights from the DS-PERS study unravel the profound influences of Li in modifying SEI formation and in turn the roles of SEI in regulating the Li-ion desolvation and the subsequent Li deposition at SEI-coupled interfaces. Last, we develop a cycling protocol that promotes a favorable direct SEI formation route, which significantly enhances the performance of anode-free Li metal batteries. The solid-electrolyte interphase is crucial for most batteries, but its characterization is challenging. Here, authors develop a depth-sensitive plasmon-enhanced Raman spectroscopy method to enable in-situ and nondestructive resolving of its structure and chemistry as well as formation mechanisms. [ABSTRACT FROM AUTHOR]

Total coliforms and Escherichia coli are the most important microbial indicators of fecal pollution. The traditional methods, such as the multiple-tube fermentation (MTF) technique and membrane-filter (MF) technique do not meet the requirements for fast and accurate testing. Recently, Defined Substrate Technology (DST) was developed to replace the traditional methods but it is a costly method and therefore, unpopular. A new membrane filter medium, MI agar, which was developed to simultaneously detect total coliforms and Escherichia coli in environmental water samples has been researched and is presented here. MI agar was compared with Endo agar, which was adopted by national standards. Spiked drinking water samples and real water samples were analyzed with duplicates by using MI agar-membrane filteration and Endo agar-membrane filteration. The results show that the average recovery rates by using MI agar method for total coliforms and Escherichia coli are 89.2% and 88.8% respectively, comparing favourably with the Endo agar method which has lower recovery rates of 81.0% and 81.2%. Thirty surface water samples were studied by using MI agar and Endo agar and the results show that there is no statistically significant difference between the two methods. The correlation coefficients by using MI agar method and Endo agar method were 0.9627 and 0.9511 for total coliforms and Escherichia coli, respectively. In summary, compared with national standards, MI agar is more sensitive, simpler to manage, less time consuming, has reduced interference effects and is suitable for the simultaneous detection of total coliforms and Escherichia coli. Since the results of this study show MI agar to be better than the current method, it meets the criteria for routine compliance monitoring of environmental water.

Telmisartan is an angiotensin II receptor blocker that displays unique PPAR-γ modulating activity. PPAR-γ Agonists have been shown to decrease susceptibility to atrial fibrillation through their antioxidant and antiapoptotic effects. The aim of this study was to determine whether telmisartan would have a greater effect on susceptibility to atrial arrhythmia in a hypertensive rat model than valsartan, which is a traditional angiotensin II receptor blocker. In this study, spontaneously hypertensive rats were treated with 10 mg *[(kg body mass).sup.-1]*[d.sup.-1] telmisartan (TEL group), 10 mg-[(kg body mass).sup.-1]*[d.sup.-1] valsartan (VAL group), or vehicle (saline; SHR group) for 4 weeks. Age-matched Wistar-Kyoto rats (WKY) were used as normotensive controls. After 4 weeks of treatment, we performed echocardiographic assessment, electrophysiological analysis, histological evaluation, and Western blot analysis. Telmisartan decreased systolic blood pressure to a similar extent as valsartan. Relative to the WKY controls, atrial arrhythmia susceptibility was significantly increased in the SHR group, and was significantly decreased by both telmisartan and valsartan, albeit to a greater extent with telmisartan. Arrhythmogenic atrial remodeling, including enlargement of the left atrium, myocyte hypertrophy, interstitial fibrosis, and myocyte apoptosis, was observed in the SHR group, and was accompanied by activated RAS-ERK signaling and suppressed PI3K-Akt-eNOS signaling. The results suggest that telmisartan reduced susceptibility to atrial arrhythmia to a greater extent than valsartan, ameliorated atrial remodeling, and reversed imbalances in the RAS-ERK and PI3K-Akt-eNOS pathways. Key words: hypertension, atrial fibrillation, structural remodeling, angiotensin receptor blockers, signaling pathway. Le telmisartan est un antagoniste du recepteur de l'angiotensine II qui exerce une activite modulatrice PPAR-γ unique. Les agonistes du PPAR-γ se sont averes diminuer la susceptibilite a la fibrillation auriculaire grace a leurs proprietes antioxydantes et anti-apoptose. Le but de cette etude etait de determiner si le telmisartan exercerait un effet sur la susceptibilite a l'arythmie auriculaire superieur a celui du valsartan, un antagoniste du recepteur de l'angiotensine II traditionnel, dans un modele de rats hypertendus. Dans cette etude, des rats spontanement hypertendus (SHR) ont ete traites avec 10 mg x [(kg de masse corporelle).sup.-1] x [jour.sup.-1] de telmisartan (TEL), 10 mg-[(kg de masse corporelle).sup.-1] x [jour.sup.-1] de valsartan (VAL) ou le vehicule (saline) pendant 4 semaines. Des rats Wistar-Kyoto (WKY) appareilles suivant l'age ont ete utilises comme controles normotensifs. Apres 4 semaines de traitement, des evaluations par echocardiographie, des analyses par electrophysiologie, des evaluations histologiques et des buvardages Western ont ete realises. Le telmisartan diminuait la pression sanguine systolique au meme degre que le valsartan. Comparativement aux controles WKY, la susceptibilite a l'arythmie auriculaire etait significativement accrue chez les rats SHR et significativement diminuee par le telmisartan et la valsartan, quoique le telmisartan ait ete plus efficace (TEL vs VAL). Un remodelage auriculaire arythmogenique, incluant l'elargissement de l'oreillette gauche, l'hypertrophie des myocytes, la fibrose interstitielle et l'apoptose des myocytes, etait observe chez les animaux SHR et il etait accompagne d'une activation de la signalisation RAS-ERK et d'une suppression de la signalisation PI3K-Akt-eNOS. Ces resultats suggerent que le telmisartan a reduit la susceptibilite a l'arythmie auriculaire dans une plus large mesure que le valsartan, a ameliore le remodelage auriculaire et a renverse les debalancements entre les voies de signalisation RAS-ERK et PI3K-Akt-eNOS. [Traduit par la Redaction] Mots-cles : hypertension, fibrillation auriculaire, remodelage structural, antagonistes du recepteur de l'angiotensine, voie de signalisation., Introduction Atrial fibrillation (AF), an important risk factor for stroke and mortality, is the most prevalent arrhythmia diagnosed in clinical practice (Wilhelmsen et al. 2001). Hypertension is a strong and [...]

Understanding the mechanism of ion rejection in the separation process remains a major hurdle in designing new membrane materials for seawater desalination. Here, we investigate the effects of water and aromatic polyamide (PA) membrane on the rejection of salt ions, such as [Fe.sup.2+], [Na.sup.+], and [Cl.sup.-], by molecular dynamic simulations. Results demonstrate that water plays a key role in salt ion rejection because salt ions preferentially interact with water molecules to form hydrates with multishell structures, which aids the rejection of various salt ions. For Fe[Cl.sub.2] aqueous solution, the innermost shell water molecules of a [Fe.sup.2+] hydrate can hardly be replaced by other substances in their molecular dynamics simulations, so ions would be highly rejected if the effective diameter of a water channel (EDC) in the membrane is smaller than that of the innermost shell of a hydrate. However, the water molecules in the second water shell can be replaced by the atoms of the membrane when the EDC is smaller than the size of the second shell (about 9 A). Besides, although the sizes of these ions approximate to those of water molecules, the rejection level of PA membrane to salt ions is higher than that to water, which is accounted for by the formation of hydrate. POLYM. ENG. SCI., 55:466-473, 2015. © 2014 Society of Plastics Engineers, INTRODUCTION Ion separation from aqueous solution has gained considerable attention in recent years due to its extensive applications in obtaining freshwater, sewage treatment, preparation of high-purity water, etc. [1-5]. Desalinations [...]

The irreversibility of the thermoelectric cooling (TEC) model could analyze and optimize refrigeration performance. In present work, a one-dimensional thermal conductivity model of the internal irreversible thermoelectric element was first established. Subsequently, two categories of evaluation indexes were further analyzed, i.e., cooling capacity Qc and coefficient of performance (COP). The thermodynamic model of TEC was then established jointly with finite time thermodynamics. The influences of current and the ratio of heat transfer areas between cold and hot sides on the steady-state characteristics of TEC were further discussed under Newtonian linear heat transfer. In addition, a transient thermodynamic model of TEC equipment was built to compare the effects of pulse width, pulse gradient, and pulse current on the cold side temperature of the TEC module. Theoretical results demonstrated that the effective working range of the steady-state operating current is 2A ≤ I ≤ 25A, and the area ratio of heat transfer between cold and hot sides is 0.07 ≤ x ≤ 1. The cooling capacity (Qc) and coefficient of performance (COP) could reach up to about 50W and 2.0, respectively. In addition, the increase of external heat transfer capacity of the hot side could reduce the transient supercooling temperature and the peak overshoot temperature, simultaneously. Afterward, the cooling capacity was remarkably enhanced. Current research could provide a reliable support for the optimization design and performance improvement of the thermoelectric cooler. Thermal conductivity model of internal irreversible thermoelectric element was established; Effects of cold and hot ends on the TEC were discussed under Newtonian linear heat transfer; Effects of pulse width, gradient and current on TEC cold end temperature were investigated; Heat transfer capacity of TEC hot end could reduce supercooling and overshoot temperatures; The irreversibility of TEC model will enhance its potentials for low grade energy exploitation. [ABSTRACT FROM AUTHOR]