batterydata/paper-abstracts huggingface dataset:
To explore the potential of molecular gas treatment of freshly cut lithium foils in non-electrolyte-based passivation of high-energy-density Li anodes, density functional theory (DFT) has been used to study the decomposition of molecular gases on metallic lithium surfaces. By combining DFT geometry optimization and Molecular Dynamics, the effects of atmospheric (N2, O2, CO2) and hazardous (F2, SO2) gas decomposition on Li(bcc) (100), (110), and (111) surfaces on relative surface energies, work functions, and emerging electronic and elastic properties are investigated. The simulations suggest that exposure to different molecular gases can be used to induce and control reconstructions of the metal Li surface and substantial changes (up to over 1 eV) in the work function of the passivated system. Contrary to the other considered gases, which form metallic adlayers, SO2 treatment emerges as the most effective in creating an insulating passivation layer for dosages ≤1 mono-layer. The substantial Li → adsorbate charge transfer and adlayer relaxation produce marked elastic stiffening of the interface, with the smallest change shown by nitrogen-treated adlayers.
Cell phones present new forms of sociality and new possibilities of encounter for young people across the globe. Nowhere is this more evident than in sub-Saharan Africa where the scale of usage, even among the very poor, is remarkable. In this paper we reflect on the inter-generational encounters which are embedded in young people’s cell phone interactions, and consider the wider societal implications, not least the potential for associated shifts in the generational balance of power. An intriguing feature of this changing generational nexus is that while many young people’s phone-based interactions, from their mid-teens onwards, are shifting away from the older generation towards friendship networks in their own age cohort, at the same time they are repositioning themselves – or becoming repositioned – as family information hubs, as a consequence of their phone expertise. The paper draws on mixed-methods research with young people aged c. 9–25years and in-depth interviews with older age-groups in 24 sites (ranging from high density poor urban to remote rural) across Ghana, Malawi and South Africa.
Polymer electrolyte fuel cell (PEFC) systems targeting applications to transfer vehicles for short-term missions and larger spacecraft in the future are being developed at NASDA. First, we designed and manufactured a system with a 100W class fuel cell. Through our tests, we found that a humidifier is not necessary when using pure hydrogen and oxygen supplied from opposite directions. In a closed simulated environment, the tests could also demonstrate the stable operation of the fuel cell system where the oxygen was recycled and the hydrogen stream was dead-ended.
The poor cycling stability and inferior rate capability of the cathodes critically restrict the application of sodium ion batteries (SIBs). Herein, we propose a strategy to optimize the electrochemical performances of P2-Na0.7Mn0.75Fe0.25-x-yNixCoyO2 cathode materials for SIBs through modulating the crystal structure with a synergistic substitution of Fe by Ni and Co. The structure-performance relationship and the synergistic improvement mechanism have been unraveled by means of x-ray diffraction, neutron diffraction and electrochemical techniques. The synergistic substitution of Fe by Ni and Co leads to the enlargement of the interlayer spacing and the Na-O bond length, and shrinks the TM-O and O-O bonds, which enhances the sodium ion diffusion coefficient, the rate capability and the cycling stability. In addition, Jahn–Teller effect is also alleviated owing to the reduction of Mn3+, which can further enhance the stability of the layered structure. Ni and Co co-doped Na0.7Mn0.75Fe0.15Ni0.05Co0.05O2 (FNC) cathode shows a relatively smooth charge-discharge curve in 1.5–4.2 V and demonstrates a much better rate performance in compared to Na0.7Mn0.75Fe0.25O2 (MF), Na0.7Mn0.75Fe0.15Ni0.1O2 (FN) and Na0.7Mn0.75Fe0.15Co0.1O2 (FC). At a high current density of 1C, 2C, 5C and 10C, FNC can still deliver a reversible capacity of 127, 109, 83 and 58 mAh g−1, respectively. FNC also provides a higher reversible capacity of 181 mAh g−1 at 0.1C with a high cycling stability. This study offers some new insights into designing high performance cathode materials for SIBs through cooperatively modulating the crystal structure with multi-elements doping.
Objective Old age has traditionally been viewed as being associated with a decline in emotional expressivity. Interestingly, empirical evidence based on analyses of facial expressions contradicts this traditionally view and points to absence of (or only very slight) age-related changes in emotional expressivity. However, this research on emotional expressivity in older persons has neglected one important emotionally colored state—expression of pain. In order to close this gap, we aimed to investigate the influence of age on the facial expression of pain. Methods Forty young (mean age, 24.1 years) and 61 elderly (mean age, 72.3 years) subjects were investigated for their facial (Facial Action Coding System) and subjective responses to noxious mechanical and electrical stimuli of various intensities. Results Young and elderly subjects did not differ with respect to the frequency of facial responses during noxious mechanical and electrical stimulations. Moreover, age had no significant impact on the pain specificity of these facial responses. Furthermore, we found no significant age differences in self-report ratings of pressure and electrical pain, thus indicating that both age groups experienced comparable amounts of pain intensities. Conclusion These findings suggest that the facial expression of pain, like facial expressions of other affective states, remains unchanged in older persons. Consequently, elderly individuals seem to communicate pain through their facial expression as validly as younger individuals do.
This work focuses on the potentials of monolithic integrated thin-film silicon solar cell and lithium ion cell in a simple cell-to-cell integration without any control electronics as a compact power solution for portable electronic devices. To demonstrate this we used triple-junction thin-film silicon solar cell connected directly to a lithium ion battery cell to charge the battery and in turn discharge the battery through the solar cell. Our results show that with appropriate voltage matching the solar cell provides efficient charging for lab-scale lithium ion storage cell. Despite the absence of any control electronics the discharge rate of the Li-ion cell through the non-illuminated solar cell can be much lower than the charging rate when the current voltage (IV) characteristics of the solar cell is matched properly to the charge-discharge characteristics of the battery. This indicates good sustainability of the ultimately simple integrated device. At the maximum power point, solar energy-to-battery charging efficiency of 8.5% which is nearly the conversion efficiency of the solar cell was obtained indicating potential for loss-free operation of the photovoltaic (PV)-battery integration. For the rest of the charging points, an average of 8.0% charging efficiency was obtained.
Solid-electrolyte interphases (SEI) play important roles in battery operations. Here, the authors report hybrid anodes by forming a Sn overlayer on alkali metal electrodes, leading to a robust SEI and consequently improved electrochemical performance.
Battery based energy storage system (ESS) has tremendous diversity of application with an intense focus on frequency regulation market. An ESS typically comprised of a battery and a power conversion system. A calculation of performance parameters is performed in this research. The aim is to formulate an in-depth analysis of the ESS in terms of power losses of the semiconductor and electrical devices, efficiency, reliability and cost which would foster various research groups and industries around the globe to improve their future product. In view of this, a relation between the operating conditions and power losses is established to evaluate the efficiency of the system. The power loss calculation presented in this paper has taken into account the conduction and switching losses of the semiconductor devices. Afterwards, the Arrhenius Life Stress relation is adopted to calculate the reliability of the system by considering temperature as a covariate. And finally, a cost calculation is executed and presented as a percentage of total cost of the ESS. It has been found that the power loss and efficiency of the ESS at rated power is 146 kW and 85% respectively. Furthermore, the mean time between failures of the ESS is 8 years and reliability remains at 73% after a year. The major cost impact observed is for battery and PCS as 58% and 16% respectively. Finally, it has been determined that further research is necessary for higher efficient and lower cost system for high penetration of energy storage system in the market.
The interfacial carrier scattering was thought to be ineffective in enhancing thermoelectric (TE) properties of polymer hybrids and there was also a lack of fundamental understanding of carrier scattering at polymer/polymer interfaces. Here we unravel the mechanism behind the role of polymer/polymer interfacial scattering on the TE properties through integration of computation and experiments. We discover that the effect of interfacial scattering at polymer/polymer interfaces on TE properties of polymer hybrids is strongly dependent on the carrier mobility of host polymers besides interfacial barriers. Only when the host carrier mobility is above a threshold, the effect of interfacial scattering on TE enhancement can be significant. Simulation suggests that the host mobility threshold is ~1cm2 V−1 s−1 for PEDOT-based polymers. The polymer hybrid system of poly(3,4-ethylenedioxythiophene) (PEDOT) nanowires/PEDOT was successfully employed to verify the theoretical results. These findings offer groundbreaking knowledge on polymer/polymer interfacial carrier-transport and will advance the design and fabrication of high-efficiency organic thermoelectric materials.
An air-breathing H2/air cell was designed for fast screening of electrolytes. In this study various electrolytes, including organic, inorganic, acidic, and basic electrolytes, were screened by comparing their effect on cell discharge performance. Focusing on organic alkaline electrolytes, several tetraalkyl ammonium hydroxide electrolytes with different molecular size and concentrations were investigated at different operating temperatures. Both electrolyte concentration and operating temperature significantly affect the cell's performance. The effect of CO2 and some acids on alkaline electrolyte's impedance and cell's discharge performance was also investigated.
The scientific community has been studying for some time a measure capable of quantifying and monitoring the well-being of the population in the territories; this measure cannot be represented exclusively by economic components but also by dimensions that represent different domains of a mainly demographic-social nature. This paper aims to consider well-being from a multidimensional point of view and measure it for the 7983 Italian municipalities in order to highlight differences and similarities. To go down to such a fine territorial detail, it was necessary to use indicators implemented by administrative sources collected in a recently published portal. The application of composite indices allows a one-dimensional measurement that makes a complex phenomenon such as well-being more readable. From a territorial point of view, moreover, the work aims to overcome the administrative division already criticized in literature because it does not allow a reading corresponding to the real behaviors and lifestyles of citizens, embracing a classification more appropriate to the objective of the study. Since the elementary indicators taken into consideration are in some way influenced by reasons of proximity and/or territorial conformation, it was decided to use the classification in Ecoregions of Italy to assess whether the well-being, within the same municipality, “moves” in relation to the municipalities ecologically homogeneous. The results of the analyses present numerous aspects of originality in which the Ecoregions draw an interesting geography of the country.
Re-thinking our relationship with energy resources and environmental equilibrium, towards anthropogenic sustainability, calls for innovative and energetically wise technologies. Smart devices adjusting their optical behaviour depending on the environmental conditions will allow remarkable energy savings. To this end, photoelectrochromic devices (PECDs) have captured, in the last two decades, the interest of many research groups and industrial players worldwide. These devices encompass a dual behavior, being able to generate energy and, concomitantly, deliver a smart optical response. For this reason, they are the ideal skins of future buildings, capable of modulating their behavior in response to changing external stimuli, like sunlight irradiance. PECDs have a wide range of applications, from solar shading in architectural glazing to rear view mirrors in automotives, or avionics. This review article explores the different design concepts standing at the basis of the devices that have appeared so far, shedding light on future perspectives. This work takes into account R&D issues and processing constraints as well as the potential exploitation of emerging solid-state materials promising important technological progress.
To improve the thermal stability of separators for lithium batteries, we have developed heat-resistant separator films based on ceramic powder. These ceramic powder based separators (CPS) consist of ceramic powder with binder resin. We used two different particle size powders of aluminum oxide (0.01 or 0.3μm). By mixing ceramic powder and resin at an appropriate content ratio, both types of CPS films satisfied needs for the heat-resistance. Furthermore, CPS film using 0.01μm powder showed excellent charge–discharge cycling properties when applied to lithium rechargeable batteries as a separator.
In the present work, dye-sensitised solar cell (DSSC) is fabricated using natural dye (Tecoma Stans)-sensitised
In this paper we present a closed-form solution to the problem of optimally charging a Li-ion battery. A combination of three cost functions is considered as the objective function: time-to-charge (TTC), energy losses (EL), and a temperature rise index (TRI). First, we consider the cost function of the optimization problem as a weighted sum of TTC and EL. We show that the optimal charging strategy in this case is the well-known Constant Current–Constant Voltage (CC–CV) policy with the value of the current in the CC stage being a function of the ratio of weighting on TTC and EL and of the resistance of the battery. Then, we extend the cost function to a weighted sum of TTC, EL and TRI and derive an analytical solution for the problem. It is shown that the analytical solution can be approximated by a CC–CV with the value of current in the CC stage being a function of ratio of weighting on TTC and EL, resistance of the battery and the effective thermal resistance.
A series of nickel foam (NF)-based composites of M x O y /RGO/Ni(OH)2 [M x O y = Co3O4, MnO2, and Ni(OH)2] with diverse multilayer nano-architectures were designed and grown in situ on NF through a one-pot hydrothermal process. Based on the redox reaction between the active NF substrate and graphene oxide (GO), along with electrostatic forces between the Mn+ ions and GO in the solution, strong interactions take place at the interfaces of M x O y /RGO, RGO/Ni(OH)2, and Ni(OH)2/Ni, and thus, there is good contact for electron transfer. These M x O y /RGO/Ni(OH)2 samples were directly used as conductive-agent- and binder-free anodes for lithium ion batteries (LIBs), and the Ni(OH)2/RGO/Ni(OH)2/NF composite electrode showed a high specific capacity, good rate capability, and excellent cycling stability, especially, it had a high reversible capacity of about 1330 mAh g−1 even after 200 cycles at 100 mA g−1. This general strategy presents a promising route for the design and synthesis of various multilayer nano-architectural transition metal oxides (hydroxide)/RGO composites on NF as energy storage materials.
Secreted proteases constitute potential virulence factors of dermatophytes. A total of seven genes encoding putative serine proteases of the subtilisin family (SUB) were isolated in Trichophyton rubrum. Based on sequence data and intron–exon structure, a phylogenetic analysis of subtilisins from T. rubrum and other fungi revealed a presumed ancestral lineage comprising T. rubrum SUB2 and Aspergillus SUBs. All other SUBs (SUB1, SUB3–7) are dermatophyte-specific and have apparently emerged more recently, through successive gene duplication events. We showed that two subtilisins, Sub3 and Sub4, were detected in culture supernatants of T. rubrum grown in a medium containing soy protein as a sole nitrogen source. Both recombinant enzymes produced in Pichia pastoris are highly active on keratin azure suggesting that these proteases play an important role in invasion of keratinised tissues by the fungus. The set of deduced amino acid sequences of T. rubrum SUB ORFs allowed the identification of orthologous Subs secreted by other dermatophyte species using proteolysis and mass spectrometry.
Dengue virus is the most significant human viral pathogen spread by the bite of an infected mosquito. With no vaccine or antiviral therapy currently available, disease prevention relies largely on surveillance and mosquito control. Preventing the onset of dengue outbreaks and effective vector management would be considerably enhanced through surveillance of dengue virus prevalence in natural mosquito populations. However, current approaches to the identification of virus in field-caught mosquitoes require relatively slow and labor intensive techniques such as virus isolation or RT-PCR involving specialized facilities and personnel. A rapid and portable method for detecting dengue virus-infected mosquitoes is described. Using a hand held battery operated homogenizer and a dengue diagnostic rapid strip the viral protein NS1 was detected as a marker of dengue virus infection. This method could be performed in less than 30min in the field, requiring no downstream processing, and is able to detect a single infected mosquito in a pool of at least 50 uninfected mosquitoes. The method described in this study allows rapid, real-time monitoring of dengue virus presence in mosquito populations and could be a useful addition to effective monitoring and vector control responses.
The special issue is one of the first attempts at exploring research interfaces between the fields of task-based language teaching (TBLT) and language integrated learning (CLIL). In this commentary, I highlight several lessons learned from the research gathered in the eight articles that comprise the special issue, pointing at fruitful research directions that the contributors open up for the future.
A great progress has been made in the field of energy harvesting over the past few years to meet the ever-increasing desire of portable, sustainable and renewable energies. Corresponding devices are designed to capture the ambient energies and convert them into usable electrical energy. Piezoelectric nanogenerator, directly scavenging a wide variety of limitless mechanical energy, has been considered as an attractive alternative over traditional rechargeable batteries for providing electrical power to various electric devices. Among piezoelectric materials, poly(vinylidene fluoride) (PVDF) and its copolymers are the most promising candidates for piezoelectric nanogenerators due to their unique electroactive properties, high flexibility, good processability, and long-term stability. However, the piezoresponse generated from their nanogenerators is still low and cannot drive most of electronic devices. Tremendous efforts have been committed to promote the technology and enhance the performance of PVDF-based piezoelectric nanogenerators. This review article highlights recent advances in their performance enhancements with fabrication techniques, piezoelectric materials, conductive and non-conductive fillers. These advanced techniques, new designs and functional materials will be helpful for the increase of piezoelectric crystal structures, alignment of dipoles, charge transfer, etc., consequently improving the output performance of piezoelectric devices. Finally, some perspectives and challenges in this field are also discussed. This comprehensive review will help researchers to learn the piezoelectricity of PVDF-based materials for efficiently converting mechanical energy into electricity, which eventually leads PVDF-based nanogenerators to be a practical power source.
Low-emission alternative bus technologies are of increasing interest to bus fleet operators due to the reduced environmental impact and potential for lower operating costs. However, with uncertainty regarding the total cost of ownership of new technologies and life cycle impacts beyond the typical well-to-wheel boundary, stakeholders may not have the necessary specific tools or evidence to evaluate life cycle impacts. The aim of this paper is to develop a novel framework to assist decision-makers in assessing the uncertainty of the life cycle impacts of alternative bus technologies. The Technology Impact Forecasting methodology was employed, integrating a life cycle model, to investigate whole life cycle impacts in an exploratory assessment environment, allowing for the analysis and trade-off evaluations of alternative drivetrain technologies and operational scenarios. This research provides a comprehensive novel framework for addressing uncertainty in whole life cycle costs and GHG emissions for the manufacture, use, maintenance and infrastructure phases of diesel and battery electric buses. Eleven scenarios are assessed in the framework, evaluating combinations of battery technologies, well-to-tank pathways, charging infrastructure and auxiliary demands. For every battery electric bus scenario, there is an 80% confidence that life cycle GHG emissions are mitigated by 10–58% compared to the baseline diesel bus, but life cycle costs are 129–247% higher. Opportunity charged electric buses employing a lithium-titanate battery are the most effective scenario for mitigating GHG emissions per additional cost of the new technology to the operator. The framework highlights a key trade-off between dependence on battery capacity and high-power charging infrastructure for battery electric bus technologies. The framework enables stakeholders to make technology adoption and resource allocation decisions based on the risk of a scenario and provides a level of confidence in a technologies’ ability to mitigate whole life cycle impacts.