This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. amorphous NiPO 4 and a minor product of nickel (II) hydroxide (β-NiOOH). During subsequent reduction, lithium ions are not fully intercalated, however, the structure is reversible and adequate for multiple cycles. The high potential in LiNiPO 4 looks to be very attractive in terms of high energy density, given the efficiency is improved.
Latent fingermarks are an important form of crime-scene trace evidence and their usefulness may be increased by a greater understanding of the effect of chemical distribution within fingermarks on the sensitivity and robustness of fingermark detection methods. Specifically, the relative abundance and micro-distribution of sebaceous (lipophilic) and eccrine (hydrophilic) material in fingermarks have long been debated in the field, yet direct visualisation of relative abundance and micro-distribution was rarely achieved. Such a visualisation is nonetheless essential to provide explanations for the variation in reproducibility or robustness of latent fingermark detection with existing methods, and to identify new strategies to increase detection capabilities. In this investigation, we have used SR-ATR-FTIR and confocal Raman microscopy to probe the spatial micro-distribution of the sebaceous and eccrine chemical components within latent fingermarks, deposited on non-porous surfaces. It was determined that fingermarks exhibit a complex spatial distribution, influenced by the ratio of lipophilic to aqueous components, and to a first approximation resemble a water-in-oil or oil-in-water emulsion. Detection of a substantial lipid component in "eccrine enriched fingermarks" (wherein hands are washed to remove lipids) is noteworthy, as it provides a potential explanation for several scenarios of unexpected fingermark detection using methods previously thought unsuitable for "eccrine deposits". Furthermore, the pronounced distribution of lipids observed in natural fingermark deposits was intriguing and agrees with recent discussion in this research field that natural fingermarks contain a much higher lipid content than previously thought.
The electrochemical performance of planar and porous zinc electrodes in an actual Zn/MnO 2 battery using lithium hydroxide ͑LiOH͒ electrolyte has been investigated. A large discharge capacity of 220 mAh/g is delivered by porous zinc electrodes while planar electrodes only deliver 130 mAh/g. The porous anode improves the rate capability of the rechargeable alkaline battery while enhancing the utilization of the active material. Using scanning electron microscopy and IR spectroscopy, the surface morphology and composition of the Zn anodes were studied at the end of the discharge process. While zincate ions and ZnO products were found after the discharge at the surface of the planar anode, no evidence for these products was found in the porous anode. The porosity of this surface prevents the detrimental buildup of zincate ions at the anodic surface that leads to passivation.The requirements for high specific energy, high specific power, and low cost materials for aqueous alkaline batteries, for example, for hybrid electric vehicle applications, make zinc an attractive negative electrode candidate. The low equilibrium potential and high overpotential for the hydrogen reaction of zinc mean that this metal has the lowest standard potential among all the elements that can be efficiently reduced from aqueous electrolytes. 1 This makes zinc uniquely suitable for high energy density batteries, and as a result, interest in the electrochemical behavior of zinc in aqueous systems has increased.Commercial, alkaline batteries using MnO 2 as cathode and Zn as the anode employing potassium hydroxide ͑KOH͒ as the electrolyte are currently in demand because they are mercury-free and have a high rate capability. This primary Zn-MnO 2 battery remains widely in use for a variety of electronic applications. 2 Recently, we showed that a primary battery can be transformed into a high performance secondary battery using aqueous lithium hydroxide ͑LiOH͒ as an electrolyte. 3 In an extension, to improve the rechargeability of our Zn͉LiOH͉MnO 2 cell suitable for high rate applications, we investigated the effects of doping the MnO 2 electrodes with a range of additives 4,5 by physically mixing them into a MnO 2 cathode. These additives were reported to suppress the formation of manganese oxyhydroxides in the MnO 2 while enhancing the lithium insertion reversibly. 4,5 The discharge performance of the LiOH alkaline battery still however needs to be significantly improved to be suitable for high power applications. Hence, in our present study we focus specifically on the anodic behavior of Zn in LiOH media.The electrochemical reaction of the zinc metal in a battery normally occurs via a dissolution-precipitation mechanism. 6,7 The utilization efficiency of Zn is lowered due to the formation of a passive film on the Zn particles preventing the metal beneath from undergoing further electron transfer. Zn anodes in commercial battery systems are generally in the form of a gelled mass or are produced by electroplating metallic Zn from a solution of Z...
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