Accurately accounting for new particle formation (NPF) is crucial to our ability to predict aerosol number concentrations in many environments and thus cloud properties, which is in turn vital in ...simulating radiative transfer and climate. Here we present an analysis of NPF events observed in the Greenland Sea during the summertime as part of the Aerosol-Cloud Coupling And Climate Interactions in the Arctic (ACCACIA) project. While NPF events have been reported in the Arctic before, we were able, for the first time, to detect iodine in the growing particles using an Aerosol Mass Spectrometer (AMS) during a persistent event in the region of the coastal sea-ice near Greenland. Given the potency of iodine as a nucleation precursor, the results imply that iodine was responsible for the initial NPF, a phenomenon that has been reported at lower latitudes and associated with molecular iodine emissions from coastal macroalgae. The initial source of iodine in this instance is not clear, but it was associated with air originating approximately 1 day previously over melting coastal sea-ice. These results show that atmospheric models must consider iodine as a source of new particles in addition to established precursors such as sulfur compounds.
Based on the concepts of the improved asymptotic iteration method, we modify the original asymptotic iteration method for perturbation problems previously published. In our computations, the proposed ...method proves to be significantly faster than the previous perturbative method as we make explicit in the examples given in this work. Our procedure enables us to compute the corrections to the energy eigenvalues to an order as high as 15 in numeric computations, and of order as high as 5 in symbolic ones.
The amount of ice present in clouds can affect cloud lifetime, precipitation and radiative properties. The formation of ice in clouds is facilitated by the presence of airborne ice-nucleating ...particles. Sea spray is one of the major global sources of atmospheric particles, but it is unclear to what extent these particles are capable of nucleating ice. Sea-spray aerosol contains large amounts of organic material that is ejected into the atmosphere during bubble bursting at the organically enriched sea-air interface or sea surface microlayer. Here we show that organic material in the sea surface microlayer nucleates ice under conditions relevant for mixed-phase cloud and high-altitude ice cloud formation. The ice-nucleating material is probably biogenic and less than approximately 0.2 micrometres in size. We find that exudates separated from cells of the marine diatom Thalassiosira pseudonana nucleate ice, and propose that organic material associated with phytoplankton cell exudates is a likely candidate for the observed ice-nucleating ability of the microlayer samples. Global model simulations of marine organic aerosol, in combination with our measurements, suggest that marine organic material may be an important source of ice-nucleating particles in remote marine environments such as the Southern Ocean, North Pacific Ocean and North Atlantic Ocean.
Abstract
This paper presents four procedures developed to analyse the dependence of the discharge curve of a lithium battery on discharge current and working temperature. For this work, two models of ...lithium batteries have been used, whose discharge curves have different shapes. The first one, the shape of the curve describes an almost horizontal line in most of it (type 1), while in the other one, the shape of the curve describes a negative slope in most of it (type 2). Two of the developed procedures are used for discharge curves with different currents but constant temperature and the other two developed procedures are used for discharge curves with different temperatures but constant current. The information for the development of the simulations is obtained from the datasheet of the analysed lithium batteries.
We tested whether periconceptional nutrition with cladodes from the cactus, Opuntia ficus-indica, with or without protein-enrichment, improved the metabolomic profile and reproductive outcomes of ...adult female sheep. Sixty Rambouillet ewes of similar body weight were randomly allocated among three nutritional treatments that were fed during the breeding period (34 days): Control (Control; n = 20), Opuntia (Opuntia; n = 20) and protein-enriched Opuntia (E-Opuntia; n = 20). There were no effects of treatment on body weight but assessment of urine samples indicated that, for 76 metabolites, the Control and Opuntia groups differed completely (P < 0.05), whereas there was overlap between the Control and E-Opuntia groups. It appears that, in Opuntia-fed and Control-fed sheep, different functional groups are activated leading to changes in the metabolism of glucose, tyrosine, methane, and glycerolipids. Fertility and reproductive rate tended to be higher in the Opuntia (70% and 95%) and E-Opuntia (90% and 110%) groups than in the Control (55% and 65%), and an orthogonal contrast revealed the difference between Control and Opuntia to be significant for both reproductive variables (P < 0.05). We conclude that nutritional supplementation with Opuntia cladodes, with or without protein enrichment, increased fertility rate and reproductive rate of female sheep, without any accompanying increases in body weight. Our observations suggest that the reproductive responses to Opuntia do not simply reflect a response to good nutrition, but might be caused by specific metabolites/metabolomic pathways, perhaps by an activation of the metabolism of glucose, methane, tyrosine and glycerolipids. There are few reports relating these metabolomic compounds with the metabolism of the sheep, let alone with reproductive efficiency. The novelty of these discoveries suggests that we need further research into the mechanisms through which nutrition affects the reproductive system.
LFP and NMC chemistries are currently, among the Li-ion family, the most relevant and with higher prospects technologies. This paper analyses the modelling process of the capacity decay in a Li-ion ...battery caused by calendar and cycling ageing. An on-line ageing estimation model valid for both LFP and NMC is developed considering the variation of the main parameters used to define the model: temperature, State of Charge and rate of charge and discharge. This model is validated from a theoretical point of view for both chemistries by comparing its performance with the data provided by manufacturers and previous ageing models. The proposed battery ageing model attains a maximum relative error of 3%, which varies depending on the battery chemistry and the specified working conditions. A further analysis regarding the model accuracy at the battery end-of-life is developed. Moreover, the model performance is validated from an experimental point of view with an NMC battery tested in the laboratory, reaching errors below 5%. In addition, a methodology for parameterizing the ageing model is proposed aiming to facilitate the application of this model into a specific battery.
•Semi-empirical expression for both LFP and NMC chemistries is developed.•Model validated theoretically with average error lower than 4%.•Model deviation below 3% for Li-ion working conditions.•Model partially validated experimentally for NMC.
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