batterydata/paper-abstracts huggingface dataset:
It is shown that the rate performance of anatase TiO2 can be significantly improved by addition of a small amount (few percent) of carefully selected oxides such as silica or RuO2. Specifically, silica serves primarily as a suppressant of particle growth during heating of anatase precursor—in our case titania nanotubes. The addition of RuO2 is supposed to enhance the electronic conductivity. The beneficial impact of the combined use of silica and RuO2 in the preparation of anatase-based electrodes is also demonstrated on a commercially available sample of anatase.
High-level visual cortex in humans includes functionally defined regions that preferentially respond to objects, faces and places. It is unknown how these regions develop and whether their development relates to recognition memory. We used functional magnetic resonance imaging to examine the development of several functionally defined regions including object (lateral occipital complex, LOC)-, face ('fusiform face area', FFA; superior temporal sulcus, STS)- and place ('parahippocampal place area', PPA)-selective cortices in children (ages 7–11), adolescents (12–16) and adults. Right FFA and left PPA volumes were substantially larger in adults than in children. This development occurred by expansion of FFA and PPA into surrounding cortex and was correlated with improved recognition memory for faces and places, respectively. In contrast, LOC and STS volumes and object-recognition memory remained constant across ages. Thus, the ventral stream undergoes a prolonged maturation that varies temporally across functional regions, is determined by brain region rather than stimulus category, and is correlated with the development of category-specific recognition memory.
This paper presents a novel energy storage system which stores excessive energy in the form of compressed air and thermal heat. It is different from the conventional compressed air energy storage (CAES) technology in that the new system allows trigeneration of electrical, heating and cooling power in energy releasing process. Uniquely, the cooling power from this system is generated by direct expansion of compressed air instead of the use of absorption chilling technology. In addition, the system can meet the end users’ demands for electricity, and heating and cooling powers through controlling the inlet pressure and temperature of an air based expander. A new parameter, the comprehensive efficiency, is proposed to evaluate the performance of the trigeneration system. Energy requirements of a small office building located in Chicago is used for the evaluation. The results show that the comprehensive efficiency of the system is very high (∼50%) in winter months when no cooling is needed. In summer months, due to the high power consumption in air compression process and inefficient expansion of the compressed air (for cooling power production) the comprehensive efficiency decreases to about 30%. However such a value is still higher than the conventional trigeneration system based on absorption chilling technology. The system is therefore very promising for practical applications particularly for the use of renewable energy due to good flexibility and simple configuration.
Aqueous Zn anodes have been revisited for their intrinsic safety, low cost, and high volumetric capacity; however, deep-seated issues of dendrite growth and intricate side-reactions hindered their rejuvenation. Herein, a “brightener-inspired” polyamide coating layer which elevates the nucleation barrier and restricts Zn2+ 2D diffusion is constructed to effectively regulate the aqueous Zn deposition behavior. Importantly, serving as a buffer layer that isolates active Zn from bulk electrolytes, this interphase also suppresses free water/O2-induced corrosion and passivation. With this synergy effect, the polymer-modified Zn anode produces reversible, dendrite-free plating/stripping with a 60-fold enhancement in running lifetime (over 8000 hours) compared to the bare Zn, and even at an ultrahigh areal capacity of 10 mA h cm−2 (10 mA cm−2 for 1 h, 85% depth of discharge). This efficient rechargeability for Zn anodes enables a substantially stable full-cell paired with a MnO2 cathode. The strategy presented here is straightforward and scalable, representing a stark, but promising approach to solve the anode issues in advanced Zn batteries.
Interconnecting different carbon building blocks, such as 1-dimensional (1D) carbon nanotubes (CNTs) and 2-dimensional (2D) graphene sheets, is an effective way to build hybrid carbon architectures with fascinating new properties. Here we report the synthesis of a binder-free reduced graphene oxide/carbon nanotube (rGO/CNT) hybrid film and its capacitive behaviour in both positive and negative potential window with 1M Na2SO4 aqueous electrolyte. It is found that intercalating small amount of CNTs into rGO sheets result in excellent specific capacitance of 272Fg−1 at a scan rate of 5mVs−1 in negative potential window of −0.8 to 0V. In contrast, moderate specific capacitance of 132Fg−1 at the same scan rate is obtained in positive potential window of 0 to 0.8V. The reason of the enhanced capacitance in negative potential window is discussed. We propose that the remarkable improvement of capacitance in negative potential window is mainly due to the strong cation adsorption at the oxidized surface of rGO sheets. The addition of CNTs can significantly improve the rate capability and cyclic stability of the electrode compared to that of pure rGO electrode. As-synthesized rGO/CNT hybrid film shows great potential in neutral aqueous electrolyte based asymmetric supercapacitors as high performance negative electrode, and other applications such as flexible batteries, seawater desalination, and biomedical applications.
Most studies examining bald eagle (Haliaeetus leucocephalus) exposure to lead (Pb) have focused on adults that ingested spent Pb ammunition during the fall hunting season, often at clinical or lethal levels. We sampled live bald eagle nestlings along waterbodies to quantify Pb concentrations in 3 national park units and 2 nearby study areas in the western Great Lakes region. We collected 367 bald eagle nestling feather samples over 8 years during spring 2006-2015 and 188 whole blood samples over 4 years during spring 2010-2015. We used Tobit regression models to quantify relationships between Pb concentrations in nestling feathers and blood using study area, year, and nestling attributes as covariates. Pb in nestling feather samples decreased from 2006 to 2015, but there was no trend for Pb in blood samples. Pb concentrations in nestling feather and blood samples were significantly higher in study areas located closer to and within urban areas. Pb in feather and blood samples from the same nestling was positively correlated. Pb in feathers increased with nestling age, but this relationship was not observed for blood. Our results reflect how Pb accumulates in tissues as nestlings grow, with Pb in feathers and blood indexing exposure during feather development and before sampling, respectively. Some nestlings had Pb concentrations in blood that suggested a greater risk to sublethal effects from Pb exposure. Our data provides baselines for Pb concentrations in feathers and blood of nestling bald eagles from a variety of waterbody types spanning remote, lightly populated, and human-dominated landscapes.
Cadmium (Cd) is a naturally occurring ubiquitous element of environmental concern. Concentrations of Cd in the geosphere are generally low except for enrichment in association with Zn, Pb, and Cu sulfidic ore deposits, as well as some phosphate rock formations. Uses of Cd include batteries, pigments, stabilizers, coatings, and some alloys. The toxicity of Cd to aquatic species depends on speciation, with the free ion, Cd2+ concentration being proportional to bioavailability. Toxicity is reduced via complexation of Cd2+ by inorganic and organic anions and through competitive interactions between Ca2+ and Cd2+ for uptake sites. Cd2+ acute toxicity involves disruption of ion homeostasis, particularly Ca, but also Na and Mg. Uptake at the fish gill occurs apically via a lanthanum-sensitive voltage-independent epithelial Ca2+ channel located in the mitochondria-rich chloride cells and basolaterally via Ca-ATPase and an Na/Ca exchanger. Chronic exposure also involves ionoregulatory disturbance and disruptions to growth, reproduction, the immune system, endocrine, development, and behavior; gill, liver, and kidney histopathologies also develop. Cadmium accumulates primarily in the kidney and liver. Accumulation has been linked to oxidative damage, which may be a mechanism linking the many different chronic effects. Uptake across gastrointestinal and olfactory surfaces is not well understood but evidence exists for gut Cd uptake via L-type voltage-gated Ca2+ channels, a high-affinity Ca2+-ATPase and a divalent metal transporter-1. Acclimation to chronic Cd exposure involves a variety of defense and detoxification processes, such as antioxidants (catalase), metallothionein, glutathione, and heat shock proteins, making the development of bioaccumulation-based impact prediction models for Cd a challenge.
The thermodynamics and kinetics of electrochemical intercalation of lithium into a Li1−δ Mn2O4 electrode have been investigated theoretically by a statistical thermodynamics concept using a Monte Carlo simulation based upon the lattice gas model. From the fluctuations in the internal energy and the number of lithium ions in the grand canonical ensemble, the partial molar internal energy and entropy of lithium ions were obtained theoretically at a fixed chemical potential. Both theoretical and experimental partial molar quantities alike showed a negative deviation from those quantities of the ideal solution below (1−δ)=0.5 and a positive deviation above (1−δ)=0.5. The component diffusivity of lithium ions was calculated with the aid of a random walk algorithm in the canonical ensemble. From the combination of the thermodynamic enhancement factor and the component diffusivity of lithium ions calculated theoretically by introducing the irreversible lithium trap sites into the Li1−δ Mn2O4 electrode, the chemical diffusivity of lithium ions was determined and compared with that measured using the galvanostatic intermittent titration technique. From the good coincidence between the chemical diffusivities calculated theoretically and determined experimentally, it was inferred that the lithium ions trapped irreversibly near structural defects disturb locally the ordering of lithium ions and hence the chemical diffusion of lithium ions in the ordered phase is strongly enhanced.
We report a novel ethylene glycol-mediated solvothermal-polyol route for synthesis of SnO2–CNT nanocomposites, which consist of highly dispersed 3–5nm SnO2 nanocrystals on the surface of multiwalled carbon nanotubes (CNTs). As anode materials for Li-ion batteries, the nanocomposites showed high rate capability and superior cycling stability with specific capacity of 500mAhg−1 for up to 300 cycles. The CNTs served as electron conductors and volume buffers in the nanocomposites. This strategy could be extended to synthesize other metal oxides composites with other carbon materials.
As part of the EuroLifeNet program we measured personal exposure to PM2.5 in 90 pupils attending three schools in Milan, over a three-week period spanning November and December 2006, using a portable light-scattering nephelometer. The primary aim was to investigate the relationship between personal exposure to PM2.5 and background measurements obtained from a fixed monitoring station. Pearson’s correlation coefficient between sampled daily mean exposures and reference values from background station varied from 0.64 to 0.75, with an overall value of 0.63, indicating good agreement. We also estimated that about 40% of the variability in the mean daily personal exposure at the three schools was due to variability in background exposure, the remaining 60% due to between-subject differences in exposures or to other sources of error.
Na0.44MnO2 is a very promising cathode material in sodium-ion batteries for large-scale application. Na0.44MnO2 with very fast sodium diffusion and stable cycling is prepared by polyvinylpyrrolidone (PVP)-combustion method. X-ray diffraction, scanning electron microscope and high-resolution transmission electron microscopy are conducted to explore the morphology and structure. Electrochemical performance of the samples is examined in coin cells with sodium foil anode and nonaqueous electrolyte. The Na0.44MnO2 sample synthesized at 900 °C (NMO-900) discharges the highest capacity of 122.9 mAh g−1 at C/5. A fast-rate-test technique developed by Newman et al. is adopted for quick determination of the rate capability. All the samples exhibit good rate capability while the NMO-900 shows the best. Normal rate test result supports the reliability of the fast rate test. Even at 20C charge and discharge rate, the NMO-900 delivers 99 mAh g−1 capacity. The chemical diffusion coefficient of sodium is measured to be around 3 × 10−12 cm2 s−1 by potential intermittent titration technique (PITT). The cycling stability is also very good. The capacity retention after 100 cycles at 1C is 87.9% and the capacity still remains 82.9% even after 700 cycles at 10C. During cycling the coulombic efficiency keeps near 99.8%.
Self-organized macroporous tungsten trioxide (WO3) films are obtained by anodic oxidation of DC-sputtered tungsten (W) layers on 10mm×25mm indium tin oxide (ITO)-coated glass. Under optimized experimental conditions, uniformly macroporous WO3 films with a thickness of ca. 350nm are formed. The film shows a connected network with average pore size of 100nm and a pore wall thickness of approximately 30nm. The anodized film becomes transparent after annealing without significant change in macroporous structure. In 0.1M H2SO4, the macroporous WO3 films show enhanced electrochromic properties with a coloration efficiency of 58cm2 C−1. Large modulation of transmittance (∼50% at 632.8nm) and a switching speed of about 8s are also achieved with this macroporous film.
Carbon-coated nano-Li4Ti5O12 (LTO) anode material was prepared and evaluated with 5.5 Ah pouch cells, paired with LiNi1/3Co1/3Mn1/3O2 cathode for potential hybrid electric vehicle (HEV) application. The as-prepared LTO batteries showed excellent electrochemical performance. They delivered a peak discharge power density of ca. 2,800 W kg−1, and featured a high power (94 and 92 % of discharge and charge capacity at 20 C, respectively) and a prolonged cycle life (89 % capacity retention after 5,000 cycles at 10 C charge and discharge rate). However, the severe capacity decay was observed at elevated temperatures because of loose (worse) interfaces caused by gas generation. It was found that H2 was the dominant gas component, and the inflation rate had an Arrhenius-type correlation with storage temperature. The battery inflation, arising from side reactions between electrolyte and LTO anode, is the major technical barrier for practical application of the LTO batteries in HEV.
Conduction aphasia is a language disorder characterized by frequent speech errors, impaired verbatim repetition, a deficit in phonological short-term memory, and naming difficulties in the presence of otherwise fluent and grammatical speech output. While traditional models of conduction aphasia have typically implicated white matter pathways, recent advances in lesions reconstruction methodology applied to groups of patients have implicated left temporoparietal zones. Parallel work using functional magnetic resonance imaging (fMRI) has pinpointed a region in the posterior most portion of the left planum temporale, area Spt, which is critical for phonological working memory. Here we show that the region of maximal lesion overlap in a sample of 14 patients with conduction aphasia perfectly circumscribes area Spt, as defined in an aggregate fMRI analysis of 105 subjects performing a phonological working memory task. We provide a review of the evidence supporting the idea that Spt is an interface site for the integration of sensory and vocal tract-related motor representations of complex sound sequences, such as speech and music and show how the symptoms of conduction aphasia can be explained by damage to this system.
Renewable energy sources (RES) for powering desalination processes is a promising option especially in remote and arid regions where the use of conventional energy is costly or unavailable. Reverse Osmosis (RO) is one of the most suitable desalination processes to be coupled with different renewable energy sources such as solar and wind. If RES/RO systems are optimally designed, some combinations can be cost effective and reliable. However, the design of such systems is complex because of uncertain renewable energy supplies, load demands and the non-linear characteristics of some components. In such system, different scenarios can be suggested; i.e combinations of PV panels, type and number of batteries, type and number of turbines, etc. Therefore, it is difficult to determine the optimal configuration with classical techniques. The development of a tool to integrate all parameters involved and compare between the possible scenarios is very important. This paper presents a new model based on the Genetic Algorithms allowing the generation of several individuals (possible solutions) for coupling small RO unit to RES. A particular interest is focused on the hybrid systems (PV/WIND/Batteries/RO). The objective function to minimize corresponds to the total water cost (Capital cost plus Operational costs). Finally, a case study of PV/RO unit, installed since 2007 in Ksar Ghilène village in southern Tunisia, is presented.
A novel method for measuring effective diffusion coefficient of porous materials is developed. The oxygen concentration gradient is established by an air-breathing proton exchange membrane fuel cell (PEMFC). The porous sample is set in a sample holder located in the cathode plate of the PEMFC. At a given oxygen flux, the effective diffusion coefficients are related to the difference of oxygen concentration across the samples, which can be correlated with the differences of the output voltage of the PEMFC with and without inserting the sample in the cathode plate. Compared to the conventional electrical conductivity method, this method is more reliable for measuring non-wetting samples.
The layered particles of lithium cobalt oxide (LiCoO2) have been modified using rotor blade grinding, re-annealing, and a combination of both treatments. SEM, XPS and EIS were used to study the effects of these treatments on the LiCoO2 particles, and changes in electrochemical behaviour in the 4-V region vs. Li+/Li were explored. After short grinding times (20min), primary layered particles formed larger aggregates and poor electrochemical behaviour was observed. After 60min grinding, LiCoO2 showed a net improvement in reversible specific capacity and capacity retention, which is due to the formation of ultrafine layered particles. Further grinding up to 180min lead to surface carbonation, increased impedances and poor electrochemical performance. Re-annealing improved the electrochemical behaviour of both ground and unground LiCoO2. The best electrochemical behaviour was observed after grinding for 60min and then re-annealing at 850°C, which is linked with a low charge transfer resistance. XPS measurements revealed that the particles surface remained unchanged after heating to 500°C, while heating to 850°C eliminated surface carbonates, and prolonged grinding yielded extended surface carbonation.
The consumption of fuel in cars can be reduced by using hybrid concepts. Even for fuel cell vehicles, a high power battery may cut costs and allow the recovery of energy during retarding. Alkaline batteries, such as nickel–metal hydride batteries, have displayed long cycle life combined with high power ability. In order to improve the power/energy ratio of Ni/MH to even higher values, the cells may be arranged in a bipolar stack design.
Electrochemical properties of plasma-fluorinated graphite samples have been investigated in 1moldm−3 LiClO4 ethylene carbonate (EC)/diethyl carbonate (DEC) solution at 25°C. Fluorine contents in plasma-fluorinated graphite samples were in the range of 0–0.3at.% by elemental analysis and surface fluorine concentrations obtained by X-ray photoelectron spectroscopy (XPS) were in the range of 3–12at.%. Raman spectroscopy revealed that surface disordering of graphite was induced by plasma fluorination. Plasma treatment increased the surface areas of graphite samples by 26–55% and the pore volumes for the mesopores with diameters of 1.5–2 and 2–3nm. Plasma-fluorinated graphites showed capacities higher than those of original graphites and even higher than the theoretical capacity of graphite, 372mAhg−1, without any change of the profile of charge–discharge potential curves. The increments in the capacities were approximately 5, 10 and 15% for graphites with average particle diameters, 7, 25 and 40μm, respectively. Furthermore, the coulombic efficiencies in first cycle were nearly the same as those for original graphites or higher by several percents.
At the moment Automobile Shredder Residue (ASR) is usually landfilled worldwide, but European draft Directive 2000/53/CE forces the development of alternative solutions, stating the 95%-wt recovery of an End of Life Vehicle (ELV) weight to be fulfilled by 2015. This work describes two industrial tests, each involving 250–300t of ELVs, in which different pre-shredding operations were performed. The produced ASR materials underwent an extended characterization and some post-shredding processes, consisting of dimensional, magnetic, electrostatic and densimetric separation phases, were tested on laboratory scale, having as main purpose the enhancement of ASR recovery/recycling and the minimization of the landfilled fraction. The gathered results show that accurate depollution and dismantling operations are mandatory to obtain a high quality ASR material which may be recycled/recovered and partially landfilled according to the actual European Union regulations, with particular concern for Lower Heating Value (LHV), heavy metals content and Dissolved Organic Carbon (DOC) as critical parameters. Moreover post-shredding technical solutions foreseeing minimum economic and engineering efforts, therefore realizable in common European ELVs shredding plants, may lead to multi-purposed (material recovery and thermal valorization) opportunities for ASR reuse/recovery.
Sn based anodes allow for high initial capacities, which however cannot be retained due to the severe mechanical damage that occurs during Li-insertion and de-insertion. To better understand the fracture process during electrochemical cycling three different nanopowders comprised of Sn particles attached on artificial graphite, natural graphite or micro-carbon microbeads were examined. Although an initial capacity of 700mAhg−1 was obtained for all Sn–C nanopowders, a significant capacity fade took place with continuous electrochemical cycling. The microstructural changes in the electrodes corresponding to the changes in electrochemical behavior were studied by transmission and scanning electron microscopy. The fragmentation of Sn observed by microscopy correlates with the capacity fade, but this fragmentation and capacity fade can be controlled by controlling the initial microstructure. It was found that there is a dependence of the capacity fade on the Sn particle volume and surface area fraction of Sn on carbon.