batterydata/paper-abstracts huggingface dataset:
Capacity fading and poor electrolyte utilization caused by electrolyte imbalance effects are major drawbacks for the commercialization of vanadium flow batteries (VFB). The influence of membrane type (cationic, anionic, amphoteric) on these effects is studied by determining the excess and net flux of each vanadium ion in an operating VFB assembled with a cation exchange membrane (CEM), Nafion® NR212, an anion exchange membrane (AEM), Fumatech FAP-450, and an amphoteric ion exchange membrane (AIEM) synthesized in-house. It is shown that the net vanadium flux, accompanied by water transport, is directed towards the positive side for the CEM and towards the negative side for the AEM. The content of cation and anion exchange groups in the AIEM is adjusted via radiation grafting to balance the vanadium flux between the two electrolyte sides. With the AIEM the net vanadium flux is significantly reduced and capacity fading due to electrolyte imbalances can be largely eliminated. The membrane's influence on electrolyte imbalance effects is characterized and quantified in one single charge-discharge cycle by analyzing the content of the four different vanadium species in the two electrolytes. The experimental data recorded herewith conclusively explains the electrolyte composition after 80 cycles.
Electrical energy storage systems such as batteries would benefit enormously from integrating all device components in three-dimensional (3-D) architectures on the nanoscale to improve their power capability without negatively impacting the device-scale energy density. However, the lack of large scale synthesis methods of 3-D architectures with precise spatial control of multiple, functional energy materials at the nanoscale remains a key issue holding back the development of such intricate device designs. To achieve fully integrated, multi-material nano-3-D architectures, next-generation nanofabrication requires departure from the traditional top-down patterning methods. Here, we present an approach to such systems based on the bottom-up synthesis of co-continuous nanohybrids with all necessary functional battery components rationally integrated in a triblock terpolymer derived core–shell double gyroid architecture. In our design three-dimensional periodically ordered, functional anode and cathode nanonetworks are separated by an ultrathin electrolyte phase within a single 3-D nanostructure. All materials are less than 20 nm in their layer dimensions, co-continuous and interpenetrating in 3-D, and extended throughout a macroscopic monolith. The electrochemical analysis of our solid-state nano-3-D Li-ion/sulfur system demonstrated battery-like characteristics with stable open circuit voltage, reversible discharge voltage and capacity, and orders of magnitude decreases in footprint area compared to two-dimensional thin layer designs.
Additional immunotoxicity tests as part of a repeat-dose toxicity study have been recommended to improve the quality of immunotoxicity assessments. Present immunotoxicity test guidelines list many tests without concreteness of methods or principles for their use. Due to the different sensitivity and specificity of each assay, numerous different test batteries can produce diverse results and make difficult inter-laboratory comparisons. To help resolve these problems and identify some of the more sensitive tests that might be used, we established immunotoxicity in a rat model using two well-known immunosuppressants and then compared the sensitivity of three important immunotoxicity tests, i.e., measures of T-cell dependent antibody responses (TDAR), ex vivo cytokine production, and immunophenotyping. The results showed that after treatment with cyclosporin A (CsA; 20 mg kg−1 d−1) or triptolide (TP; 0.8 mg kg−1 d−1), production of interleukin (IL)-2, interferon (IFN)-γ, tumor necrosis factor (TNF)-α, and the antibody to keyhole limpet hemocyanin (KLH) were significantly inhibited; in contrast, there were only weak or sporadic changes to host histopathology and hematology. With regard to phenotyping, no significant changes were noted in the ratios of CD4+:CD8+ cells in the treated hosts. Taken together, the results here suggest to us that cytokine production and the KLH TDAR assay are very sensitive parameters to define an agent as immunotoxic, while immunophenotyping and histopathology – while being more expensive/time-consuming – appear to be less sensitive options for an individual assessing the immunotoxic potential of a given test agent.
Objective Cognitive deficits are common in epilepsy, though the impact of epilepsy on cognition in older adults is understudied. This study aimed to characterize cognition in older adults with epilepsy compared with healthy older adults and identify potential risk factors for impairment. Methods Thirty-eight older adults with epilepsy and 29 healthy controls completed a comprehensive neuropsychological battery, as well as measures of depression and anxiety. Chart review for current medications, seizure history, and neuroimaging was also completed. To compare cognitive performance between groups, ANOVA was used, and linear regression identified predictors of impairment among the group with epilepsy. Results Patients with epilepsy performed worse across nearly all cognitive domains, and were clinically impaired (i.e., ≥1.5 SD below mean) on more individual tests when compared with controls, including a subset of patients with epilepsy with normal MRIs. For all patients with epilepsy, taking a greater number of antiepileptic drugs was associated with poorer language and visuospatial abilities, and higher anxiety was associated with poorer visual memory. Conclusions Older adults with epilepsy demonstrated greater cognitive deficits than matched controls. Polytherapy and anxiety heightened the risk for cognitive impairment in some cognitive domains, but not in others. Understanding the nature of cognitive decline in this population, as well as associated risk factors, may assist in the differential diagnosis of cognitive complaints and improve the design of treatment studies for older patients with epilepsy. Replication in larger, longitudinal studies is warranted to generalize these findings.
Publisher Summary This chapter provides design guidelines and hardware information, specific case studies, and a checklist for representative security applications. It analyzes specific applications and hardware, specifications, and questions to be asked and answered for several specific scenarios. Applications covered in the chapter apply to facilities occupied by governmental agencies, manufacturers, industrial companies, and retail and commercial business services. The video surveillance applications include lobbies, elevators, offices, rear doors, shipping areas, hallways, cashier checkout areas, and warehouses. Temporary and permanent covert video systems are used in installations for viewing the general public entering a facility as well as for monitoring employees. Wide field of view (FOV) optics and zoom lenses are used for parking lots and perimeter-fenceline environments. The video systems described in the chapter are indoor and outdoor, analog or digital, and single site, multiple sites, and remote site. The rapid deployment application includes a wireless alarm-intrusion system. In view of this large installed base of analog equipment, many new installations will still be performed using new analog equipment.
In the last of a series of experiments 48 3–5-year old children were tested on an alternative naming game with “synonyms,” e.g., if puppet calls the depicted item a “rabbit” the child has to call it a “bunny,” or the child has to judge puppet’s performance when roles are reversed. The game was also played with categories (rabbit–animal), name/colour (rabbit–black), colour/colour (black–white), and part/part (head–tail). The younger children (≤3.5 years) had severe problems with “synonyms” and categories (alternative names for the items, <10% correct), but not with names and colours, only colours, or only parts (>80% correct). Children’s increasing success with age on the alternative names tasks was closely paralleled (.53≤r≤.72) by their mastery of the false belief task in which they had to predict that a mistaken story character would look for a desired object in the wrong location. For explaining the synchrony between alternative naming and understanding false belief we draw on the Piagetian idea that children come to represent perspective at some point in their development. To apply this idea to the alternative naming game we draw on the philosophical discussion about sortals (terms that specify what sort of object something is) creating perspective differences.
Lithium-sulfur battery is one of the most prospective chemistries in secondary energy storage field due to its high energy density and theoretical capacity, but the rapid decay of capacity is still a huge challenge. Herein, we reported an ingenious design of nitrogen doped carbon nanofibers with honeycomb-like porous structure for the cathode of lithium-sulfur battery which can effectively suppress the “shuttle effect”. The special porous material with three dimensional (3D) interconnected pore structure is beneficial to enhance the adsorption of lithium polysulfides and accommodate the volume expansion of active materials. In addition, the doped nitrogen can not only improve the conductivity of cathode, but also form a strong interfacial interaction to trap lithium polysulfides. Therefore, the battery with the cathode exhibited a high reversible discharge capacity of 1093.9 mAh g−1 and good capacity retention of 76.0% after 300 cycles at 0.5C rate. After acidification, the cycling performance of the cathode could achieve upon 300 cycles with a very low decay rate of 0.027% at 0.5C.
The dye-sensitized mesoscopic solar cell has been intensively investigated as a promising photovoltaic cell. Its ecological and economical fabrication processes make it attractive and credible alternative to conventional photovoltaic systems. In contrast to the latter design, the DSC approach separates tasks of light absorption and charge transport. The primary step of light absorption is performed by a sensitizer anchored to the surface of a wide band gap semiconductor. In order to reach a high conversion efficiency, the first requirement is that the sensitizer should absorb as much as possible of the incoming sunlight. Strategies for achieving panchromatic response in dye-sensitized mesoscopic solar cells are discussed.
Carbon-based electrodes are promising for flow batteries. While cerium redox reactions on carbon materials have been investigated, further studies are of necessity to improve the fundamental understanding of the impact of surface functionalization on reaction kinetics. An electrochemical study of the cerium redox reaction on glassy carbon (GC) electrode, as a standard carbon-based material, provides insights into the mechanism and underlying factors. Thus, an in situ electrochemical treatment is proposed to activate GC, and its influence on the kinetic parameters is demonstrated. Furthermore, a comprehensive investigation on reaction kinetics of cerium is conducted on activated GC, where the impact of sulfuric acid and methanesulfonic acid supporting electrolytes is studied. Moreover, the results reflect the contributions of different cerium complexes on electron transfer and diffusion processes.
The growth of silver doped vanadium pentoxide was performed by aerosol assisted chemical vapour deposition and found to be optimal at 450°C. Additionally, an increase in crystallinity and a change in preferred orientation of V2O5 was observed upon increasing the silver content. Silver incorporation also resulted in morphological changes in the thin films from rod to pellet-like structures. For higher silver content films the amount of incorporated charge increased and reversibility and repeatability was demonstrated for 500 cycles. Electrochemical impedance spectroscopy determined that the transfer and diffusion of Li+ ions through the cathode-electrolyte interface was assisted by silver loading, hence, enhancing the capacitive performance.
A three-dimensional (3D) reticular CoMn2O4/C anode with pomegranate-like configuration was synthesized via electrostatic spray deposition technique. It was found that the residual solvents which were generally considered as by-product also acted as a key role in the structure control. By simply varying the feeding rate at a certain temperature in the process, both the structure and the content of carbon in the products were controllable. The percolated reticular structure, accompanying with double-layer carbon coatings in the pomegranate-like construction, were considered to improve the electrochemical stability even for a longtime discharging/charging at high rate. Due to the re-oxidation of Mn during delithiation and the stable 3D reticular structure, the as-prepared 3D reticular anode with pomegranate-like configuration exhibited high specific capacities (1386.6-695.3mAhg−1 at 0.3–15Ag−1) and good cyclic stability (626.3mAhg−1 retained after 600 cycles at 12Ag−1). The approach in this study may provide a new strategy to fabricate other electrode materials based on transition metal oxides for energy storage application.
Tetragonal Li7La3Zr2O12 (LLZ) was synthesised by the solid-state and citrate–nitrate methods. The crystal structure of the samples was characterised by the X-ray diffraction method. The morphology of the particles was investigated using both optical microscopy and a particle size analysis method. The ceramic samples were studied by complex impedance spectroscopy in the frequency range from 12 to 105 Hz, in the temperature range of 20–400°C. Synthesis by the citrate–nitrate method makes it possible to reduce both the temperature and time of the synthesis and also prepare the product with smaller particles. The conductivity of LLZ synthesised by the citrate–nitrate method (5.2×10−6 Scm−1 at 20°C) is higher than the conductivity of LLZ synthesised by the solid-state method (1.3×10−6 Scm−1 at 20°C).
Distributed, controllable energy storage devices offer several benefits to electric power system operation. Three such benefits include reducing peak load, providing standby power, and enhancing power quality. These benefits, however, are only realized during peak load or during an outage, events that are infrequent. This paper presents a means of realizing additional benefits by taking advantage of the fluctuating costs of energy in competitive energy markets. An algorithm for optimal charge/discharge scheduling of Community Energy Storage (CES) devices as well as an analysis of several of the key drivers of the optimization are discussed.
Ethanolic and hexanic extracts from fruits and leaves of Schinus molle showed ability to control several insect pests. Potential vertebrate toxicity associated with insecticidal plants requires investigation before institutional promotion. The aim of the present study was to evaluate the acute and subacute toxicity of ethanolic extracts from fruits of Schinus molle in rats. The plant extract was added to the diet at 2g/kg body weight/day during 1 day to evaluate acute toxicity and at 1g/kg body weight/day during 14 days to evaluate subacute toxicity. At the end of the exposure and after 7 days, behavioral and functional parameters in a functional observational battery and motor activity in an open field were assessed. Finally, histopathological examinations were conducted on several organs. In both exposures, an increase in the arousal level was observed in experimental groups. Also, the landing foot splay parameter increased in the experimental group after acute exposure. Only the subacute exposure produced a significant increase in the motor activity in the open field. All these changes disappeared after 7 days. None of the exposures affected the different organs evaluated. Our results suggest that ethanolic extracts from fruits and leaves of Schinus molle should be relatively safe to use as insecticide.
Hybridization of dissimilar materials is a promising solution to improve desired properties in various applications. Herein, we chemically grew a conductive polymer (polypyrrole, PPy) on graphene-supported manganese ferrite microspheres (MG, ∼344 nm in size) to form PPy/MG hybrids at various PPy contents (20, 33.3, and 42.9 wt%). PPy, MG binary, and PPy/MG ternary hybrids were comprehensively characterized to correlate their structure, morphology, and properties. Electrochemical measurements revealed a significantly enhancement of capacitive performances of PPy/MG as comparison to those of each component. Consequently, the combination of PPy and MG resulted in maximum specific capacitance of 147.2 F/g at scan rate of 10 mV/s or 66.1 F/g at current density of 0.5 A/g. These synergistic and cooperative effects are attributed to reduced diffusion resistance in the PPy/MG hybrids. This work thus suggests an efficient strategy to develop high-performance material for supercapacitor electrode.
The performance of a tunable diode laser (DL) spectrometer is directly determined by the DL qualities and its tunability control. Emission characteristics are very sensitive to current and temperature drifts. In order to obtain a high quality source for spectroscopy, we designed our own liquid nitrogen cryostat containing the DL. Moreover we compared current and temperature control and we found that temperature tuning can be more efficient. We check and demonstrate it by recording SO2 spectra in the 1168–1169 cm–1 spectral region.
Titanium dioxide (TiO2) has been considered as a promising anode candidate for sodium ion batteries (NIBs). In this work, we report the synthesis of anatase TiO2 nanosheets coated by nitrogen doped carbon derived from dopamine precursor (TiO2@C) as high performance anode materials for NIBs applications. The carbon contents can be controlled from 2.6wt% to 10.4wt% by varying the polymerization time of dopamine. X-ray diffraction patterns confirm there is no phase change after carbon coating. When employed as an anode for NIBs, the TiO2@C composites exhibit improved electrochemical performances in terms of higher specific capacity and better cycling stability compared to pure TiO2 nanosheets. Notably, with a carbon content of 4.8wt%, the TiO2@C nanosheets delivers a reversible capacity of 180mAhg−1 and shows stable cycling performance with no discharge capacity decay from 2nd cycle onward over 50 cycles. Even at high current density of 10C, the capacity still remains 82mAhg−1. The excellent cycling stability and rate performances can be ascribed to the protective effects of carbon coating layer which reserves the structure stability and enhances electrical conductivity during cycling.
A two-dimensional two-phase steady state model of the cathode of a polymer electrolyte membrane fuel cell (PEMFC) is developed using unsaturated flow theory (UFT). A gas flow field, a gas diffusion layer (GDL), a microporous layers (MPL), a finite catalyst layer (CL), and a polymer membrane constitute the model domain. The flow of liquid water in the cathode flow channel is assumed to take place in the form of a mist. The CL is modeled using flooded spherical agglomerate characterization. Liquid water is considered in all the porous layers. For liquid water transport in the membrane, electro-osmotic drag and back diffusion are considered to be the dominating mechanisms. The void fraction in the CL is expressed in terms of practically achievable design parameters such as platinum loading, Nafion loading, CL thickness, and fraction of platinum on carbon. A number of sensitivity studies are conducted with the developed model. The optimum operating temperature of the cell is found to be 80–85°C. The optimum porosity of the GDL for this cell is in the range of 0.7–0.8. A study by varying the design parameters of the CL shows that the cell performs better with 0.3–0.35mgcm−2 of platinum and 25–30wt% of ionomer loading at high current densities. The sensitivity study shows that a multi-variable optimization study can significantly improve the cell performance. Numerical simulations are performed to study the dependence of capillary pressure on liquid saturation using various correlations. The impact of the interface saturation on the cell performance is studied. Under certain operating conditions and for certain combination of materials in the GDL and CL, it is found that the presence of a MPL can deteriorate the performance especially at high current density.
The iron tungstate materials Fe2W y O3(y+1) (y =1 and 3) have been synthesized by a low temperature route, and their lithium insertion properties measured using galvanostatic and EVS measurements. This paper reports the lithium insertion into Fe2WO6, Fe2W3O12 and nano-composite Fe2WO6/WO3 materials made by this co-precipitation route. Relatively high initial discharge capacities were observed for all materials, the highest being 653.9mAhg−1 for the y =3 material heat treated at 500°C. Rapid capacity fade behaviour was observed for all materials prepared at 500°C. Improved performance was determined for the iterations heat treated at 950°C with a reversible specific capacity of 320mAhg−1 observed for the Fe2WO6 sample.
Errors and uncertainty within the experimental results have long-term implications in lithium-ion battery research. Experimental directly feed into the development of different battery models, thus having a direct impact on the accuracy of the models, which are commonly employed to forecast short to long term battery performance. The estimations made by such models underpin the design of key functions within the BMS, such as state of charge and state of health estimation. Therefore, erroneous experimental results could evolve into a much larger issue such as the early retirement of a battery pack from the end-use application. For original equipment manufacturers (OEM), such as automotive OEMs this may have a significant impact, e.g. high warranty returns and damage to the brand. Although occasionally reported in published results, currently, little research exists within the literature to systematically define the error and uncertainty of battery experimental results. This article focuses on the fundamental sources of error and uncertainty from experimental setup and procedure and suggests control measures to remove or minimize the contributions from the sources identified. Our research shows that by implementing the control measures proposed, the error and uncertainty can be reduced to around 0.6%, from the figure of around 4.0%.
Iron-nitrogen-carbon (Fe-N-C) materials featuring Fe-N4 moieties are promising candidates to replace commercial Pt/C catalysts for the oxygen reduction reaction (ORR). Here we report a novel Mn-Fe-N/S@mC catalyst comprising atomically dispersed Fe-N4 sites and a trace amount of Mn-N2S2 sites, which are homogeneously anchored on an ordered mesoporous graphitic carbon framework. This dual-metal catalyst is realized based on the chemical conversion of self-assembled Mn0.43Fe2.57O4 nanocrystal supracrystals, with the dual metal sites and the graphitic framework derived from nanocrystal cores and the associated capping ligands, respectively. When evaluated as electrocatalysts for the ORR, Mn-Fe-N/S@mC exhibits excellent catalytic activity in alkaline media, outperforming conventional Pt/C and most non-precious-metal catalysts reported previously. Notably, the synergistic effect of having Fe and Mn together improves the catalytic activity by a factor of ~ 5. To better understand the high efficiency of Mn doping in enhancing the activity of Fe-N4 sites, density functional theory calculations were carried out, revealing that the synergistic interaction between the dual metal sites reduces the *OH reduction energy barrier during the oxygen reduction pathway.