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The following paper proposes methods for the formation of high-performance interface electrode materials to increase the effectiveness of signal collection from the patient’s body during electrocardiography (ECG). The electrode materials are produced via the hybridisation of commercial ECG liquid hydrogels with carbon nanotubes (CNT), often used to manufacture dry ECG electrodes. The hybrid materials were prepared by mixing hydrogels with CNT powders and wrapping them in macroscopic CNT films. In both solutions, the liquid hydrogels ensure good wetting of the epidermis, while CNTs decrease the impedance of the material and stabilise the drying process. In addition, composite materials remain soft, ensuring microconformal attachment to skin and are biocompatible. Thus such hybrid solutions combine the advantages of wet and dry ECG electrode technologies and, therefore, could enable long-term monitoring of ECG signals leading to better diagnosis and treatment of many heart disorders.

Although the "skunky" odor characteristic of cannabis has been widely referenced, its cause has been historically misassigned to

Solving environmental odor issues can be confounded by many analytical, technological, and socioeconomic factors. Considerable know-how and technologies can fail to properly identify odorants responsible for the downwind nuisance odor and, thereby, focus on odor mitigation strategies. We propose enabling solutions to environmental odor issues utilizing troubleshooting techniques developed for the food, beverage, and consumer products industries. Our research has shown that the odorant impact-priority ranking process can be definable and relatively simple. The initial challenge is the prioritization of environmental odor character from the perspective of the impacted citizenry downwind. In this research, we utilize a natural model from the animal world to illustrate the rolling unmasking effect (RUE) and discuss it more systematically in the context of the proposed environmental odorant prioritization process. Regardless of the size and reach of an odor source, a simplification of odor character and composition typically develops with increasing dilution downwind. An extreme odor simplification-upon-dilution was demonstrated for the prehensile-tailed porcupine (P.T. porcupine); its downwind odor frontal boundary was dominated by a pair of extremely potent character-defining odorants: (1) ‘onion’/‘body odor’ and (2) ‘onion’/‘grilled’ odorants. In contrast with the outer-boundary simplicity, the near-source assessment presented considerable compositional complexity and composite odor character difference. The ultimate significance of the proposed RUE approach is the illustration of naturally occurring phenomena that explain why some environmental odors and their sources can be challenging to identify and mitigate using an analytical-only approach (focused on compound identities and concentrations). These approaches rarely move beyond comprehensive lists of volatile compounds emitted by the source. The novelty proposed herein lies in identification of those few compounds responsible for the downwind odor impacts and requiring mitigation focus.

Solving environmental odor issues can be confounded by many analytical, technological, and socioeconomic factors. Considerable know-how and technologies can fail to properly identify odorants responsible for the downwind nuisance odor and mitigate it for the affected citizenry. We propose enabling solutions to environmental odor issues by utilizing troubleshooting techniques developed for the food, beverage, and consumer products industries. We showed that the downwind odorant impact-priority ranking process can be definable and relatively simple. The initial challenge is the prioritization of environmental odor character from the perspective of the impacted citizenry downwind. In this research, we aim at summarizing three natural models of the rolling unmasking effect (RUE) and discuss them more systematically in the context of the proposed downwind environmental odor prioritization approach. Regardless of the size and reach of an odor source, a simplification of odor character and composition typically develops with downwind dilution. The extreme odor simplification-upon-dilution was demonstrated for two plant varieties, prairie verbena and Virginia pepperweed. Their downwind odor frontal boundaries were dominated by single, character-defining odorants; p-cresol-dominated ‘barnyard’ odor, and benzyl mercaptan-dominated ‘burnt match’ odor, respectively. The P.T. porcupine downwind odor frontal boundary was dominated by two potent, character-defining odorants: (1) ‘onion’/‘body odor’ odorant #1 and (2) ‘onion’/‘grilled’ odorant #2. In contrast with their downwind boundary simplicities, each odor source presented considerable compositional complexity and composite character difference near the source. The proposed RUE approach’s ultimate significance is the illustration of naturally occurring phenomena that explain why some environmental odors and their sources can be challenging to identify and mitigate using the analytical only approach (focused on compound identities and concentrations). These approaches rarely move beyond comprehensive lists of compounds being emitted by the source.

Downwind odor characteristics can be very different depending upon the size of the upwind point-source, interim topography, and wind conditions. At one extreme, the downwind odor plume from a relatively large, confined animal feeding operation (CAFO), located on a flat open plain and under stable, near-straight-line wind conditions can be rather broad, sustained and predictable relative to a fixed receptor site downwind. In contrast, the plume from a small point-source (e.g., a roof vent stack) located on irregular topography and under rapidly shifting wind conditions can be intermittent and fleeting. These transient odor events can be surprisingly intense and offensive, in spite of their fleeting occurrence and perception. This work reports on efforts to optimize an environmental odor sampling strategy, which is optimized for the challenges of (1) sampling of such transient odor 'spikes' and (2) the prioritization of odors/odorants from multiple, closely co-located point-sources, under such transient event conditions. Protocol refinement has emerged by way of 2 environmental odor assessment projects which have been undertaken on behalf of the Missouri Department of Natural Resources. The challenge of transient odor events has been mitigated utilizing rapid, odor cued whole-air grab capture sampling into metalized-FEP gas sampling bags, followed by immediate adsorption transfer onto SPME fibers or sorbent tubes for stabilization during the shipment and storage interval between collection and final analysis. Initial results demonstrated approximately 11 fold increases in target odorant yields for 900 mL sorbent tube transfers from 2-3 second 'burst' odor event bag-captures, as compared to equivalent direct collections at the same downwind receptor location but during perceived (stable) odor 'lull' periods. Results-to-date targeting refinement and field trials of this integrated environmental odor assessment strategy are presented. Preliminary application targeting general odor sampling and point-source differentiation utilizing tracer gases is also presented.

Lower Cambrian salt deposits in the eastern Officer Basin occur in troughs along the western and northwestern margin of the Gawler Craton, and are interpreted to have been deposited in marginal to restricted marine environments. The salt horizons in two drillholes [Manya 6 (373554E, 6938478N: GDA94) and Wilkinson 1 (263545E, 6693435N: GDA94)] were studied utilising multiple techniques including mineralogical investigation, fluid inclusion and isotopic analysis. New data on Br values of 19 salt samples provide evidence of marine origin for the salt. Abundant two-phase (gas – liquid) inclusions and poor preservation of primary inclusions indicate intensive post-depositional recrystallisation. Homogenisation studies of fluid inclusions in halite from Manya 6 suggest that the upper part of the salt-bearing strata (Ouldburra Formation) has been heated to 80°C, whereas the lower part reached even higher temperatures. This heating event may be related to the Devonian – Carboniferous Alice Springs Orogeny. The ch...

Downwind odor impact characteristics can be very different depending upon the size of the upwind point-source, interim topography and wind patterns. At one extreme, the downwind odor plume from a relatively large confined animal feeding operations (CAFO), located on a flat open plain and under stable, near-straight-line wind conditions can be rather broad, sustained and predictable relative to a fixed downwind receptor site. Conversely, the plume from a small point-source (e.g. such as a vent stack) located on irregular topography and under rapidly shifting wind patterns can be intermittent and fleeting. These transient odor events can be surprisingly intense and offensive, in spite of their fleeting occurance and perception. This work reports on efforts to develop a downwind odor sampling strategy which is optimized for sampling of such transient odor 'spikes'. This approach is based on combined air sampling with improved-material bags and preconcentration onto sorbent tubes. Initial results have been very promising. For example, approximate 10 fold increases in target odorant yields were realized for 900 mL sorbent tube transfers from 1-2 second 'burst' odor event bag-captures; when compared to equivalent direct collections at the same downwind receptor location but during perceived (stable) odor 'lull' periods. Results-to-date targeting refinement and validation of this integrated strategy for transient odor events are presented. Application to general odor sampling and point-source differentiation utilizing tracer gases is also presented.

Past experience with crisis-driven odor investigations has shown that there is an odor impact priority ranking which is definable for virtually every malodor issue; whether from natural or synthetic source. An accurate definition of such odorant priority ranking is, in turn, critical to the development of accurate and objective instrument-based methods for odor assessment and monitoring relative to that source. This paper reports on the results-to-date relative to the Carthage Bottoms Area Odor Study; a test case undertaken by the Missouri DNR to evaluate the concept of odorant prioritization by MDGC-MS-Olfactometry. The ultimate goal of this study was to explore the utility of odorant prioritization as a first step toward the translation of sensory-only odor monitoring protocols to sensory-directed but instrument based alternatives. The Carthage Bottoms Area was selected by the Missouri DNR for this exploratory effort based upon a number of factors: including; (1) an intermittent but long-standing unresolved odor issue with respect to downwind citizenry; (2) a uniquely complex, diverse and densely co-located source industry mix within the combined Bottoms Area; (3) limited past success in point-source differentiation utilizing sensory-only protocols and (4) a past history of cooperation between citizenry, community officials, industry leaders and regulatory agencies in the exploration and implementation of technologies targeting enhanced mutually beneficial co-existance. MDGC-MS-O odorant profile and prioritization results are presented for SPME collections taken near and at-distance downwind as well as reference upwind with respect to the combined Bottoms Area.

The detection and identification of substances that give rise to aromas and off-odors is often a difficult task. Perception of odors is very subjective and odor detection thresholds vary from person to person. The identification of trace levels of compounds responsible for perceived odors is difficult using conventional analytical tools. This paper will focus on a novel method for sampling and analyzing aromatic volatile compounds using an analytical system specifically designed for odor analysis.

Normal pulse staircase, and reverse pulse voltammetry together with polarography and double potential step chronocoulometry were employed to examine the electrode processes of Ga(III) at mercury electrodes in solutions containing NaSCN at 4 M ionic strength. Thiocyanate ions were found to catalyze the reduction of Ga(III) with the reaction order of 1. No faradaic evidence of and thiocyanate-induced adsorption of Ga(III) was found. The formal potential Ga(III)/Ga(0) was found to be −0.731 V vs. SCE (25°C, pH 2.0 4 M NaClO 4 ), and the formation constant β 2 =[Ga(SCN) 2 + ]/[Ga 3+ ][SCN − ] 2 was determined under the same condtions, as log β 2 =5.6±0.1.