batterydata/paper-abstracts huggingface dataset:
Anteromesial temporal lobectomy (AMTL) is an effective and safe treatment for refractory temporal lobe epilepsy (TLE) caused by hippocampal sclerosis (HS). It is possible that modifications to this procedure could offer improved seizure control or a reduction in functional consequences in some patients. Reviewed here is the issue of when it might be appropriate to perform a resection for TLE that spares the mesial structures, particularly the hippocampus and parahippocampal gyrus. This issue is particularly important for dominant hemipshere TLE and for patients without obvious HS, as these are the patients at greatest risk for verbal memory decline following AMTL. Current evidence suggests that mesial structure-sparing resections may be worth consideration for two types of patients: those with temporal lobe foreign tissue lesions outside the mesial structures, and those with temporal lobe hypometabolism on fluorodeoxyglucose positron emission tomography but a normal MRI. Patients with dual pathology (i.e., HS plus another epileptogenic lesion) are unlikely to benefit from a resection that spares the mesial temporal lobe. There is little evidence to state whether resections of this kind are worthwhile for cryptogenic TLE, or for mesial TLE with preserved memory function. There is a clear need to move beyond the field’s present focus on the hippocampus and investigate new approaches to TLE that may minimize the risks of functional consequences in patients without HS.
Electrolytes containing LiB(C2O4)2 (LiBOB) salts are of increasing interest for lithium-ion cells for several reasons that include their ability to form a stable solid electrolyte interphase on graphite electrodes. However, cells containing these electrolytes often show inconsistent performance because of impurities in the LiBOB salt. In this work we compare cycling and impedance data from cells containing electrolytes with LiBOB that was obtained commercially and LiBOB purified by a rigorous recrystallization procedure. We relate the difference in performance to a lithium oxalate impurity that may be a residual from the salt manufacturing process. We also examine the reaction of LiBOB with water to determine the effect of salt storage in high-humidity environments. Although LiBOB electrolytes containing trace amounts (∼100ppm) of moisture appear relatively stable, higher moisture contents (∼1wt%) lead to observable salt decomposition resulting in the generation of B(C2O4)(OH) and LiB(C2O4)(OH)2 compounds that do not dissolve in typical carbonate solutions and impair lithium-ion cell performance.
A review of the recent developments in the study and understanding of room temperature ionic liquids are given. An intimate picture of how and why these liquids are not crystals at ambient conditions is attempted, based on evidence from crystallographical results combined with vibrational spectroscopy and ab-initio molecular orbital calculations. A discussion is given, based mainly on some recent FT-Raman spectroscopic results on the model ionic liquid system of 1-butyl-3-methylimidazolium ([C4mim][X]) salts. The rotational isomerism of the [C4mim]+ cation is described: the presence of anti and gauche conformers that has been elucidated in remarkable papers by Hamaguchi et al. Such presence of a conformational equilibrium seems to be a general feature of the room temperature liquids. Then the “localized structure features” that apparently exist in ionic liquids are described. It is hoped that the structural resolving power of Raman spectroscopy will be appreciated by the reader. It is of remarkable use on crystals of known different conformations and on the corresponding liquids, especially in combination with modern quantum mechanics calculations. It is hoped that these interdisciplinary methods will be applied to many more systems in the future. A few examples will be discussed.
Abstract This chapter offers a general discussion of one of the more prominent issues facing America today, such as water conservation and using water more efficiently. Wastewater Strategy and Water Reuse/Recycling Reclaimed Water versus Gray water SYSTEMS are defined and explained. Also explained is the LEED Innovative Wastewater Technologies credit and its intent to reduce wastewater generation and potable water demand, as well as increase the recharge of local aquifers. Best practice strategies for landscape irrigation are elucidated. The various types of toilets (e.g., high efficiency, dual flush, and composting toilets), urinals (e.g., waterless urinals) and metering faucets, aerators and flow-optimized showerheads are also examined. Baseline water consumption calculations are explained and finally, retention and detention ponds, bioswales, and other systems are discussed.
A hermetic noble-metal-free membrane-less microbial solar cell (MSC) is established. The substances decomposition and regeneration in this MSC are carried out only by Chlorella vulgaris simultaneously. The conversion of metabolism types of C. vulgaris is controlled only by illumination. By using a pleiotropic redox mediator and a cupric hexacyanoferrate modified cathode, a two-phase three-stage charge transfer chain is formed. Through this pathway, the one microorganism self-sustained system gets a long-term power output up to 0.04773 mW/cm2 at 0.423 V without any material exchange with external, which is 50 times higher than that obtained from the original system. Benefiting from this electron buffer system, the battery will achieve an electricity generation in both light and dark conditions. There is almost no consumption of any substrates throughout the stabilized process, and no more additions are required. This maintenance-free and extremely inexpensive reactor with a simple structure and a long service life demonstrates the possibility of combining the microbial, chemical and photo cells.
Thermal degradation products in lithium-ion batteries result mainly from hydrolysis sensitivity of lithium hexafluorophosphate (LiPF6). As organic carbonate solvents contain traces of protic impurities, the thermal decomposition of electrolytes is enhanced. Therefore, resulting degradation products are studied with nuclear magnetic resonance spectroscopy (NMR) and gas chromatography mass spectrometry (GC–MS). The electrolyte contains 1 M LiPF6 in a binary mixture of ethylene carbonate (EC) and diethylene carbonate (DEC) in a ratio of 1:2 (v/v) and is aged at ambient and elevated temperature. The impact of protic impurities, either added as deionized water or incorporated in positive electrode material, upon aging is investigated. Further, the influence of different housing materials on the electrolyte degradation is shown. Difluorophosphoric acid is identified as main decomposition product by NMR-spectroscopy. Traces of other decomposition products are determined by headspace GC–MS. Acid–base and coulometric titration are used to determine the total amount of acid and water content upon aging, respectively. The aim of this investigation is to achieve profound understanding about the thermal decomposition of one most common used electrolyte in a battery-like housing material.
The cyclic performance of a composite SiO and carbon nanofiber (CNF) anode was examined for lithium-ion batteries. SiO powder of several micrometers was pulverized using high energy mechanical milling. The SiO was ball-milled for 12h with CNF to produce a composite electrode material that exhibited excellent cycling performance. A reversible capacity of approximately 700mAhg−1 was observed after 200 cycles. The excellent cyclic performance was discussed with respect to the change of the valence state of Si by ball-milling. A large irreversible capacity at the first cycle for the SiO/CNF composite electrode was reduced to 2% by chemically pre-charging with a lithium film attached to the rim of the electrode.
An unprecedentedly high electronic conductivity of 0.27Scm−1 is achieved by depositing 0.56wt% crystalline RuO2 on LNMO via a wet-chemical route. Systematic assessment of the electrochemical performance of bare and RuO2-coated LNMO electrodes unambiguously demonstrates that the high electronic conductivity of RuO2 enables significant enhancement in rate capability. These improvements are dramatic for the electrodes in which extremely low amounts of carbon additives are included and/or the loading amount is high. This finding highlights the importance of electronic conduction in composite electrodes, not only for high power but also for high energy density. The RuO2-coated LNMO electrode with 1wt% carbon additives exhibits a high capacity of 100mAhg−1 at 1C in the range 3.0–5.0V (vs. Li/Li+). This result is in sharp contrast to the negligible capacity exhibited by the bare LNMO electrode. In addition, the chemical/electrochemical stability of the RuO2 coating under repeated cycling is confirmed, explaining the observed improvement in durability of the RuO2-coated LNMO over the bare LNMO.
Publisher Summary This chapter discusses nuclide distribution between steelmaking phases upon melting of sealed radioactive sources hidden in scrap. Sealed radiation sources are widely used in industry, medicine, and research. Although there are regulations in many states on the management of disused radioactive sources, the steel industry is aware of the possibility that disused sources are lost to regulatory control. Since most sealed sources have an outer containment made of steel, a certain fraction of the orphan sources might be discarded as plain steel scrap and be sold to the steel industry. The chapter reports the thermochemical calculations related to nuclide partitioning between the steelmaking phases according to equilibrium calculations.
The charging process of Li2O2-based air electrodes in Li–O2 batteries with organic carbonate electrolytes was investigated using in situ gas chromatography/mass spectroscopy (GC/MS) to analyze gas evolution. A mixture of Li2O2/Fe3O4/Super P carbon/polyvinylidene fluoride (PVDF) was used as the starting air electrode material, and 1-M lithium bis(trifluoromethylsulfonyl)imide (LiTFSI) in carbonate-based solvents was used as the electrolyte. We found that Li2O2 was actively reactive to 1-methyl-2-pyrrolidinone and PVDF that were used to prepare the electrode. During the first charging (up to 4.6V), O2 was the main component in the gases released. The amount of O2 measured by GC/MS was consistent with the amount of Li2O2 that decomposed during the electrochemical process as measured by the charge capacity, which is indicative of the good chargeability of Li2O2. However, after the cell was discharged to 2.0V in an O2 atmosphere and then recharged to ∼4.6V, CO2 was dominant in the released gases. Further analysis of the discharged air electrodes by X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy indicated that lithium-containing carbonate species (lithium alkyl carbonates and/or Li2CO3) were the main discharge products. Therefore, compatible electrolytes and electrodes, as well as the electrode-preparation procedures, need to be developed for rechargeable Li-air batteries for long term operation.
In this paper, graphite nanosheets were modified by aminopyrene (Amin), 1-pyrenecarboxylic acid (PCA) and cetyltrimethyl ammonium bromide. Based on physical (field-emission scanning electron microscopy, high-resolution transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and Raman spectroscopy) and electrochemical tests (cyclic voltammetry, electrochemical impedance spectroscopy and galvanostatic charging/discharging curves), their physical and chemical properties were investigated. The physical characterization and electrochemical performance analysis indicated that the different reducing agents, technical methods and small organic molecules significantly influenced the precipitation of MnO2. When the small organic molecule was PCA, the G/MnO2 composite material had the best electrochemical capacity and stability. PCA possesses four rings; therefore, PCA can interact with graphite layers and peel off the graphite to form MnO2/single-layer graphene. During the loading of MnO2, PCA did not influence the structure of MnO2 crystals. After modification by PCA, the MnO2/C composite possessed long-term cycling stability. The changes in the morphological and structural evolutions in nanocrystalline MnO2 for the MnO2/C composite differed from those observed for pure MnO2.
In this paper we report on the development and demonstration of physically consistent three-dimensional models for Lithium Ion Battery (LIB) cells. The discharge behavior of a LIB is a multiphysics and multiscale problem that is simulated using coupled models for thermal, electrical, and electrochemical phenomena. The individual physics models and software are integrated into a new open computational framework for battery simulations which was designed to support a variety of modeling formulations and computer codes. Several cell configurations (unrolled cell, unrolled cell with current collectors, large capacity pouch cell, and cylindrical cell) that show the importance of coupled simulations are simulated using this approach and discussed. A validation study is presented for the pouch cell discharged under high rates to demonstrate the accuracy of the proposed modeling framework.
Colour can improve the visual aesthetics of solar cells for building and product integration but constitutes an optical loss from the perspective of photovoltaic energy conversion. To quantify this compromise, we report the theoretical efficiency limits of ideal coloured opaque single-band-gap solar cells. The colours were optimized by allowing the solar cells to reflect light within two distinct wavelength bands in the visible region. Colour chromaticity and brightness were controlled by modifying the position and width of the reflection bands, while optimising the band-gap energy for each colour. We found that almost the entire sRGB colour space has an efficiency limit greater than 29%, when relative luminosity is less than 0.25. This corresponds to a relative performance loss of less than 14% compared to an ideal black solar cell. Yellow-green is the most efficient photovoltaic colour, whereas highly saturated blue, red and purple colours produce the lowest efficiencies, when compared at equal brightness. The colour-dependence is explained by the photopic sensitivity of the human eye, which peaks at yellow-green wavelengths and tails towards the blue and red ends of the visible spectrum. For most colours, except the darkest ones, the optimal band-gap energy for a theoretically ideal solar cell is between 1.115 eV and 1.135 eV, matching the value for crystalline silicon. The results clarify the link between the solar cell colour and efficiency and establish a reference point and guidelines for optimizing coloured photovoltaics.
Exposure–response studies and policy evaluations of household air pollution (HAP) are limited by current methods of exposure assessment which are expensive and burdensome to participants.
Lithium sulfide (Li2S) cathodes have been viewed as very promising candidates for next-generation lightweight Li and Li-ion batteries. Prior work on the deposition of carbon shells around Li2S particles showed reduced dissolution of polysulfides and improved cathode stability. However, due to the substantial volume changes during cycling and the low chemical binding energy between carbon and sulfides, defects almost inevitably forming in the carbon shell during battery operation commonly lead to premature cell failure. In this study, we show that conformal coatings of layered LiTiO2 may offer better protection against polysulfide dissolution and the shuttle effects. Density functional theory (DFT) calculations revealed that LiTiO2 exhibits a strong affinity for sulfur species (Li2Sx) and, most importantly, induces a rapid conversion of longer (highly soluble) polysulfides to short polysulfides, which exhibit minimum solubility in electrolytes. Quite remarkably, even the mere presence of the electronically conductive layered oxides (LiMO2, M = metal) such as LiTiO2 in the cathodes (e.g., as a component of the mix with Li2S) enhanced the cell rate and cycling stability dramatically. Advanced material characterization in combination with quantum chemistry calculations provided unique insights into the mechanisms of the incredible performance boost, such as interactions between Li2Sx and the LiTiO2 surface, leading to breakage of S–S bonds.
Gastro-oesophageal reflux disease (GERD) is a highly prevalent condition in Western countries leading to millions of outpatient visits per year. GERD symptoms including heartburn, regurgitation and chest pain are caused by reflux of gastric content in the oesophagus even in the absence of endoscopically visible mucosal lesions. Several procedures are used to identify gastro-oesophageal reflux, the clinically widely used are: conventional (catheter-based) pH monitoring, wireless oesophageal pH monitoring (Bravo), bilirubin monitoring (Bilitec), and combined multichannel intraluminal impedance–pH monitoring (MII–pH). Each technique has strengths and limitations of which clinicians and investigators should be aware when deciding which to choose in a particular patient. Important is the ability to quantify gastro-oesophageal reflux and evaluate the relationship between symptoms and reflux episodes. The present review summarises the technical aspects in performing and interpreting esophageal reflux monitoring procedures.
Vehicle manufacturers worldwide are recognizing the need to elevate the electrical system voltage on their product from the present standard of 12 V to a significantly higher, yet safe, voltage. One of the major challenges emerging from the move to higher voltages is the size, weight, volume, cost and complexity of the battery required to support such a system. Inspira™, a valve-regulated, lead–acid, spiral-wound Thin Metal Foil™ battery, provides a small, lightweight, flexible solution to the challenge.
Assessing operator situation awareness is a key component of sociotechnical system design and evaluation. This article describes a study that was undertaken in order to compare two different situation awareness measures (a freeze probe recall approach and a post trial subjective rating approach) when used to assess participant situation awareness during a military planning task. The results indicate that only the participant situation awareness scores derived via the freeze probe recall method produced a statistically significant correlation with performance on the planning task and also that there was no significant correlation between the two methods, which suggests that they were measuring different aspects of participant situation awareness during the trials. In conclusion, the findings, whilst raising doubts over the validity of the post trial subjective rating approach, offer validation evidence for the use of freeze probe recall approaches to measure situation awareness during simulated tasks. The findings are subsequently discussed with regard to their wider implications for the future measurement of situation awareness in complex collaborative systems. Relevance to industry Situation Awareness is a critical commodity for teams working in industrial systems. Accordingly, designers and analysts require reliable and valid methods for assessing the impact of new systems, interfaces, training programs and procedures on the level of situation awareness held by operators. This article presents a review and comparison of situation awareness measurement approaches for use in complex industrial systems and provides recommendations on the types of methods to use during future situation awareness assessments.
A polymer gel electrolyte composed of a poly(ethylene oxide) derivative, poly(ethylene oxide-co-2-(2-methoxyethoxy) ethyl glycidyl ether), mixed with gamma-butyrolactone (GBL), LiI and I2 is employed in dye sensitized solar cells (DSSC). The electrolyte is characterized by conductivity experiments, Raman spectroscopy and thermal analysis. The influence of the electrolyte composition on the kinetics of DSSC is also investigated by transient absorption spectroscopy (TAS). The electrolyte containing 70wt.% of GBL and 20wt.% of LiI presents the highest conductivity (1.9×10−3 Scm−1). An efficiency of 4.4% is achieved using this composition. The increase in I SC as a function of GBL can be attributed an increase in the mobility of the iodide (polyiodide) species. The increase in the yield of the intermediate species, I2 −, originating in the regeneration reaction, is confirmed by TAS. However, the charge recombination process is faster at this composition and a decrease in the V oc is observed. Photovoltage decay experiments confirm an acceleration in charge recombination for the DSSC assembled with the electrolyte containing more GBL. Raman investigations show that in this electrolyte the I5 −/I3 − ratio is higher. Theoretical calculations also indicate that the I5 − species is a better electron acceptor.
Nitrogen-doped mesoporous carbon hollow spheres (N-MCHSs) were prepared using mesoporous silica hollow spheres as template and dopamine as carbon precursor. The N-MCHSs demonstrate high specific surface area and vegetable sponge-like mesoporous shell with interconnected “carbon bridges”, facilitating continuous electron transport and Li ion diffusion, and making the whole structure more stable. The influence of N contents and N-bonding configuration on the Li storage of N-MCHSs is discussed. The N-MCHSs carbonized at 800 °C demonstrate high reversible capacity and excellent rate performance, delivering a capacity of 485 mAh g−1 at a current of 0.5 A g−1 after 1,100 cycles. Even up to 4.0 A g−1, a high capacity of 214 mAh g−1 can be remained. The high electrochemical performance of N-MCHSs can be ascribed to mesoporous carbon hollow spheres structure and high level pyridinic nitrogen doping.
As the share of renewable energy sources in the energy mix is increasing, new challenges arise regarding the grid integration. This research focuses on a solution for one of these challenges, namely the employment of batteries to address the mismatch in electrical power between electricity supply from photovoltaic systems and household electricity demand. Herein, the optimal sizing of batteries for household self-consumption is combined with peak shaving at district level, whereas previous studies only looked at these questions in isolation. Our analysis makes use of a unique set of power measurement data from 79 households in the Dutch city of Amersfoort, in 295 evenly distributed days, with a resolution of 10 s. By using simulation of batteries and Net Present Value analysis, the average optimal storage size for self-consumption in the case of net metering abolishment for households with photovoltaic systems was determined to be 3.4 kWh. Large differences were observed between different households; photovoltaic system size, total net metered consumption and specific characteristics of load profiles resulted into optimal storage sizes in the range of 0.5–9 kWh. The impact of these optimally sized batteries on neighborhood peak demand was assessed and found to be limited, corresponding to a decrease of 5.7%. The peak shaving potential was further assessed under different control strategies of the batteries. Results show that the impact could be amplified to a decrease of 22% or 51% when the batteries are controlled by using heuristics or by assuming perfect foresight together with a power minimization algorithm, respectively. The findings of this paper emphasize the importance of collaboration between households and other stakeholders, such as distributed system operators and retailers in transitioning to a sustainable power system.