batterydata/paper-abstracts huggingface dataset:
Convergent evidence from task-based functional magnetic resonance imaging (fMRI) studies suggests a posterior-to-anterior shift as an adaptive compensatory scaffolding mechanism for aging. This study aimed to investigate whether brain functional dynamics at rest follow the same scaffolding mechanism for aging using a large Chinese sample aged from 22 to 79 years (n = 277). We defined a probability of brain regions being hubs over a period of time to characterize functional hub dynamic, and defined variability of the functional connectivity to characterize dynamic functional connectivity using resting-state fMRI. Our results revealed that both functional hub dynamics and dynamic functional connectivity posited an age-related posterior-to-anterior shift. Specifically, the posterior brain region showed attenuated dynamics, while the anterior brain regions showed augmented dynamics in aging. Interestingly, our analysis further indicated that the age-related episodic memory decline was associated with the age-related decrease in the brain functional dynamics of the posterior regions. Hence, these findings provided a new dimension to view the scaffolding mechanism for aging based on the brain functional dynamics.
Publisher Summary This chapter provides an overview of the genetic epidemiology of normal human growth and development describing how auxologists can most profitably approach the study of the genetics of growth and development. It also describes the most important quantitative genetic terms and the concepts that are used in understanding genetic epidemiology of normal growth and development. A number of different study designs can be used to examine the genetics of complex traits. Each study design has certain advantages and disadvantages. This chapter discusses major types of study designs used by genetic epidemiologists to study complex quantitative traits. It also provides an overview of studies on genetic factors in growth and development that have been conducted over the last century. These reviews focus on studies of height, birth weight, menarche, and skeletal development. Finally the author highlights the topics discussed in the chapter through examples of genetic analyses conducted over the years in the Fels Longitudinal Study and those currently underway in the recently established Jiri Growth Study.
Honey, a widely existent biomass, consists mainly of carbohydrate and other nitrogen-containing substances such as proteins, enzymes and organic acids. It can be mixed homogeneously with mesoporous silica template for its excellent water-solubility and moderate viscosity. In this work, honey was employed as a nitrogen-containing carbon precursor to prepare nitrogen-doped ordered mesoporous carbons (OMCs). The obtained honey derived mesoporous nitrogen-doped carbons (HMNCs) with dilated interlayer spacings of 0.387–0.395 nm, narrow pore size distributions centering at around 4 nm and satisfactory N contents of 1.38–4.32 wt% offer superb dual functionality for lithium ion battery (LIB) and sodium ion battery (NIB) anodes. Tested against Li, the optimized HMNC-700 delivers a superior reversible capacity of 1359 mA h g−1 after 10 cycles at 100 mA g−1 and excellent rate capability and cycling stability of 722 mA h g−1 after 200 cycles at 1 A g−1. For NIB applications, HMNC-700 offers a high initial reversible capacity of 427 mA h g−1 and stable reversible capacity of 394 mA h g−1 at 100 mA g−1.
Separators are needed in microbial fuel cells (MFCs) to reduce electrode spacing and preventing electrode short circuiting. The use of nylon and glass fiber filter separators in single-chamber, air-cathode MFCs was examined for their effect on performance. Larger pore nylon mesh were used that had regular mesh weaves with pores ranging from 10 to 160 μm, while smaller pore-size nylon filters (0.2–0.45 μm) and glass fiber filters (0.7–2.0 μm) had a more random structure. The pore size of both types of nylon filters had a direct and predictable effect on power production, with power increasing from 443 ± 27 to 650 ± 7 mW m−2 for pore sizes of 0.2 and 0.45 μm, and from 769 ± 65 to 941 ± 47 mW m−2 for 10 to 160 μm. In contrast, changes in pore sizes of the glass fiber filters resulted in a relatively narrow change in power (732 ± 48 to 779 ± 43 mW m−2) for pore sizes of 0.7 to 2 μm. An ideal separator should increase both power density and Coulombic efficiency (CE). However, CEs measured for the different separators were inversely correlated with power production, demonstrating that materials which reduced the oxygen diffusion into the reactor also hindered proton transport to the cathode, reducing power production through increased internal resistance. Our results highlight the need to develop separators that control oxygen transfer and facilitate proton transfer to the cathode.
Based on the voltammetric behaviour of a series of methyl-substituted benzenes in 1M LiPF6/EC-DMC electrolyte, xylene was selected and tested as an electrolyte additive for overcharge protection of Li-ion batteries. From the overcharge curves, CV behaviour and SEM observations of the cells in the presence of xylene, it was found that the additive can polymerize at the overcharged voltage to form a dense layer of isolating polymer film at the cathode surface, which blocks off further oxidation of the electroactive material and electrolyte and, therefore, improves the overcharge tolerance of the Li-ion battery. In addition, the xylene additive has shown only a slight influence on the cycling behaviour.
Fifty granitic rock samples were collected from different plutons in the central part of the Eastern Desert of Egypt and were analyzed for specific concentrations of 238U, 232Th and 40K radionuclei. The measurements were carried out using a high performance and stability Nomad Plus spectroscopy system attached to a 1.7 keV (FWHM) HPGe detector. The spectra were analyzed using the direct gamma counting comparison method as well as the traditional absolute efficiency curve method. The highest average value of 238U concentration (1184 Bq kg−1) was observed at EI Misikat region whereas the highest average values of 40K and 232Th concentration (2301.8 and 162.5 Bq kg−1 respectively), were detected at Gabal Homret Waggat area. The radium equivalent activity (Raeq), the absorbed dose rate (D), the external hazard index (H ex) and the annual gonadal dose equivalent were also calculated and compared to the international recommended values. Radon exhalation rate from the rock samples were measured using the activated charcoal canister method. The average value of radon exhalation varies from 0.052 to 0.69 Bq m−2 h−1 and depends on the specific concentration of uranium.
A building integrated semi-transparent photovoltaic thermal (BiSPVT) system involves an integration of semi-transparent photovoltaic modules with buildings along with the provision to harvest thermal energy and provide daylighting. In this paper, a thermal model has been developed for a 7.2 kWp BiSPVT system to evaluate the yearly energy generation potential of the system. Through the experiments performed on the system with variation in number of air changes per hour (N) in its room, the efficacy of the model has been presented. It has been found that N creates negligible decrease in PV cell temperature whereas with N = 11 (day2) and N = 22 (day3), the maximum room temperature has been found to decrease by 1.3 °C and 1.9 °C respectively. Further, the efficiency of SPV array has been evaluated in real time i.e. with the array connected to balance of system (power conditioning unit (PCU), AC load, battery bank). The average efficiency of SPV array when loaded at maximum power point by the PCU is found to be 6.90%. The total energy generated in a year by the BiSPVT system is found to be 8927.1 kWh. Additionally, the impact of poor health of battery bank on electricity generation for standalone PV systems has been presented.
Li2S with theoretical capacity of 1166mAhg−1 has been considered as a promising candidate for Li-S cathode as it could be paired with safer Li-free electrodes to resolve safety issues. However, the success is hindered by the nature of Li2S and corresponding reduction species, including low conductivity and the shuttling phenomenon. Herein, we simply coat graphene films directly onto the Li2S cathode, which can suppress polysulfides dissolution effectively. The electrochemical performance of the cathode depending on graphene interlayer thickness (0, 20, 45, 54, 77 and 88μm) has been investigated. Li2S cathode with the 45μm thick interlayer exhibits initial discharge capacity of 1029.21mAhg−1 and 779.74mAhg−1 at 0.05C and 0.1C, respectively, and capacity retention of above 60% with coulombic efficiency of around 90% over 300 cycles at high C rates. The results are discussed in terms of the graphene film thickness and the conductivity of the film as well as Li ion diffusivity.
Highly concentrated solutions of sodium bis(fluorosulfonyl)imide (NaFSI) with a series of bis(fluorosulfonyl)imide-based ionic liquids incorporating either alkyl phosphonium or alkoxy ammonium cations (P111i4FSI:NaFSI, P1i4i4i4FSI:NaFSI), N2(2O2O1)3FSI:NaFSI) are combined with NaFePO4 cathodes to demonstrate excellent cycling performance with respect to potential range, rate capability, cycle life and elevated temperature stability. With a capacity of 85 mAhg−1 and a capacity retention of 95% over 100 cycles (50 °C, C/2) P111i4FSI:NaFSI matches or outperforms conventional organic solvent based electrolytes as well as other ionic liquid electrolytes in terms of capacity, elevated temperature performance and cycle stability. The electrolyte conductivity does not correlate with the capacity, suggesting that this is not the primary factor determining the cell performance. The solid electrolyte interphase determines the cycle stability with SEM and XPS techniques suggesting the presence of NaOH, Na2S and NaF on the Na metal surface post cycling.
The robustness of conductive networks and the accessibility of electrolyte into the network are important factors in designing the cathode electrode for lithium/sulfur (Li/S) batteries containing liquid electrolytes that involve liquid phase electrochemical reactions. We show that the performance of Li/S cells can be significantly improved by simply optimizing the electrode processing conditions to have open pore structures and mechanical integrity of the electrode architecture. It is demonstrated that the capacity of 1000 mAh g−1 at 0.1 C and the stable capacity retention of >700 mAh g−1 after 200 cycles at 0.5 C can be achieved with relatively high sulfur content of 68%. 417 Wh kg−1 in specific energy and 623 Wh l−1 in energy density are achievable with this new technology.
Ni-doped spinel oxides NixCo1-xFe2O4 (x=0, 0.25, 0.5, 0.75) hollow nanospheres electrocatalysts are synthesized with a simple hydrothermal approach. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) results reveal that the morphology, hollow and spinel structures of the cobalt ferrites remain unchanged with doping. The electrocatalytic activity of the Ni-doped CoFe2O4 with different doping contents has been studied and compared with the pure CoFe2O4 hollow nanospheres in alkaline solution by using rotating ring-disk electrode (RRDE) technique. For ORR, the Ni0.5Co0.5Fe2O4 (x=0.5) exhibits as the most active catalyst with the highest diffusion limited current density and more positive onset potential. Whereas, the Ni0.75Co0.25Fe2O4 (x=0.75) shows the best catalytic activity for OER with more negative onset potential (0.27V vs. Ag/AgCl) and maximum current density (36.0mA/cm2 at 1.0V). X-ray photoelectron spectra (XPS) measurements reveal that the oxygen vacancy on the oxide surfaces increases, while the cations occupied ratio on octahedral/tetrahedral sites in spinel structures decreases along with the increasing of the Ni doping content. Combining with the charge transfer resistance measured by electrochemical impedance spectroscopy (EIS), these three factors work synergistically on the catalytic activities of the Ni-doped CoFe2O4 hollow nanospheres.
Among the various crystallographic phases of nickel hydroxide, the β-form is the most widely used as the active mass of the positive electrode of nickel-based secondary cells. However, the exact electrochemical and structural behaviour of the β(II)/β(III) redox system upon cycling and ageing remains to be clarified. This work reports the electrochemical behaviour under galvanostatic conditions of two non-doped Ni(OH)2 samples having different initial crystallography and morphology. The evolution of these features is investigated as a function of the cycling conditions and more particularly as a function of the reduction state achieved on discharge. Electrodes cycled at the 1st discharge plateau show that charged/discharged active materials are very similar. However, when discharge is continued down to the so-called ‘second discharge plateau’, drastic changes are observed as an increase of the crystallisation degree and of the compactness of the Ni(OH)2 powder. Some insights into the nickel electrode redox behaviour are given. It appears that the nickel electrode operates, upon charge, as a single-phase or as a mixed-phase system depending on the depth of discharge.
The authors report the synthesis of ZnO nanorods on flexible and transparent mica substrates. The coupled use of polyethylenimine and ammonium hydroxide provided a direct method for growing vertically well-aligned ZnO nanorods with a high aspect ratio. Using mica as a substrate material enabled thermal annealing processes, which improved the structural and optical properties of ZnO nanorods with uniform surface coverage and excellent adhesion, increased transmittance of indium tin oxide (ITO)/mica (52%), and decreased sheet resistance of ITO/mica (80%). We have fabricated ZnO nanorod-based dye-sensitized solar cells (DSSCs) and piezoelectric nanogenerators (NGs) and investigated their annealing effects on the device performances. Specifically, the thermal treatment at 500°C for 30min increased the energy conversion efficiencies of DSSCs by 53%. Furthermore, we observed a three-fold increase in the NG׳s output voltage and output current density through this thermal annealing process. As shown below, mica, which can function under extremes of temperature, is useful as a substrate for flexible and transparent electronics.
Although alcohol and distraction are often cited as significant risk factors for traffic crashes, most research has considered them in isolation. It is therefore necessary to consider the interactions between alcohol and distraction impairment sources, especially when examining the relationship between behavior and crash risk. In a driving simulator, the primary goal was to maintain a safe headway to a lead vehicle and the secondary goal was to maintain stable lane position. All participants engaged in distractions that represented different levels of resource competition and half of the participants consumed alcohol (target BAC 0.08g/dl). Specific comparisons were made between sober driving while distracted and driving intoxicated without distraction. Distraction tasks produced more changes in driving behavior than did alcohol for both longitudinal (primary) and lateral (secondary) driving goals. Alcohol impairment was evident only in relation to lateral driving performance, however there was an amplification of impairment when alcohol and distraction conditions were combined. Distraction resulted in a general level of impairment across all driving goals, whereas participants with alcohol appeared to shed secondary driving goals to “protect” primary driving goals. Drivers’ strategies to cope with alcohol (and distraction) may not be sufficient to offset the increased crash risk.
The manufacture of lithium nickel manganese cobalt oxides (NMC) suspensions for cathodes is typically performed with organic solvents like N-methyl-pyrrolidone (NMP) or N-ethyl-2-pyrrolidone (NEP). It is widely known that these substances are caustic and toxic to reproduction. The utilization of water for the preparation of a cathode suspension is less hazardous and saves costs. Unfortunately NMC alkalinizes the water to a very pH value, which leads to a pit corrosion of the aluminum substrate. The development and optimization of water-based NMC suspensions therefore must include investigations on lowering the pH value without deteriorating the electrochemical performance of the material. One option is the addition of amphoteric oxidic additives. This work focusses on Al2O3 and SiO2 as additives and explores their effects on the pH of the suspension and on the substrate corrosion as well as on the electrochemical performance of the NMC-cathode prepared therefrom. Furthermore the impact of the particle sizes of the additives was studied.
An innovative setup to combine electrochemical and in situ surface X-ray diffraction (SXRD) measurements is described. This electrochemical cell has a different design from the other ones commonly used for X-ray diffraction studies. It allows the sample surface to stay always completely immersed into the solution under controlled potential conditions even during the SXRD measurements. The X-ray beam crosses the liquid (about 1cm) and the cell walls. Because of the high X-ray energy, the beam attenuation is negligible and by an appropriate positioning of the detector arm slits it is possible to minimize the diffuse scattering induced by the liquid and cell walls in order to still detect the minima of the crystal truncation rods (CTRs). The liquid solution in the cell is managed by a special device, which allows the controlled exchange of the electrolyte solutions necessary in the electrochemical atomic layer epitaxy (ECALE) growth. The whole setup can be remotely controlled from outside the experimental hutch by a dedicated computer. As an example we report measurements on S layers deposited at underpotential on the Ag(111) surface, and on CdS films of increasing thickness.
DCLR-P was prepared by direct coal liquefaction residue (DCLR) with ash removal. In the present experiments, mesocarbon microbeads (MCMBs) were prepared by co-carbonization of coal tar pitch (CTP) and DCLR-P. With the increase of DCLR-P content, the yield of MCMBs increased from 47.8% to 56.8%. At the same time, the particle sizes distribution of MCMBs was narrowed, resulting in the decrease of D90/D10 ratio from 154.88 to 6.53. The results showed that DCLR-P had a positive effect on the preparation of MCMBs. 1H-NMR, FTIR, SEM and XRD were used to analyze the mechanisms and characteristics of MCMBs prepared by co-carbonization of CTP and DCLR-P. The results showed that the Proton Donor Quality Index (PDQI) of DCLR-P was 13.32, significantly higher than that of CTP (0.83). This indicated that DCLR-P had more naphthenic structure than CTP, which leads to hydrogen transferring in polycondensation reaction. The aliphatic structure of DCLR-P can improve the solubility and fusibility of mesophase, thereby making the structure of MCMBs more structured. The microstructure of the graphitized MCMBs had a substantially parallel carbon layer useful for its electrical performance. The performance of graphitized MCMBs as a negative electrode material for Li-ion batteries was tested. The particle sizes, tap density, specific surface area and initial charge–discharge efficiency of graphitized MCMBs met the requirements of CMB-I in GB/T-24533-2009. However, the initial discharge capacity of graphitized MCMB was only 296.3 mA h g−1 due to the low degree of graphitization of MCMBs.
The high voltage LiNi0.5Mn1.5O4 cathode with a disordered spinel structure is synthesized by a glycine-assisted low-temperature reaction follows by a thermal treatment at 750°C, 850°C, and 950°C for 12h. Glycine is used as a chelating agent for the first time to build required environment for shaping the precursor of LiNi0.5Mn1.5O4 materials. The microstructure and morphology of the LiNi0.5Mn1.5O4 product are characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, Brunauer-Emmett-Teller, and transmission electron microscopy. The sample prepares at 750°C reveals small particles with well-defined crystals as confirmed by electron microscopy. Electrochemical results demonstrate that LiNi0.5Mn1.5O4 electrode anneal at 750°C (compare to other two samples) delivers the highest reversible capacity of 110mAhg−1 at 0.2C after 100 cycles with good rate capability. The enhanced electrochemical performance could be attributed to the smaller particle sizes as well as well-defined crystals which provide a directional and shorter diffusion path length for Li+ transportation within the crystals.
Increasing power and energy demands for next-generation portable and flexible electronics such as roll-up displays, photovoltaic cells, and wearable devices have stimulated intensive efforts to explore flexible, lightweight and environmentally friendly energy storage devices. Flexible solid-state supercapacitors (SCs) have attracted increasing interest because they can provide substantially higher specific/volumetric energy density compared to conventional capacitors. Additionally, flexible solid-state SCs are typically small in size, highly reliable, light-weight, easy to handle, and have a wide range of operation temperatures. In this regard, solid-state SCs hold great promise as new energy storage devices for flexible and wearable electronics. In this article, we review recent achievements in the design, fabrication and characterization of flexible solid-state SCs. Moreover, we also discuss the current challenges and future opportunities for the development of high-performance flexible solid-state SCs.
Neural network force fields promise to bypass the computationally expensive quantum mechanical calculations typically required to investigate complex materials, such as lithium-ion batteries. Mailoa et al. accelerate these approaches with an architecture that exploits both rotation-invariant and -covariant features separately.
A 3D electrochemical-thermal coupled finite element analysis (FEA) model is established on COMSOL Multiphysics® software for 40 A h ternary prismatic lithium-ion batteries. The input parameters in this model are current C-rate C, battery thickness Th bat , initial battery ambient temperature T int , positive porous electrode thickness Th pos , positive particle diameter D pos , positive electrode solid phase volume fraction ε 1,pos , respectively. Response surface methodology (RSM) with variance analysis (ANOVA) and parametric scanning is employed for simulating and optimizing the data obtained from the Box-Behnken experimental design based on this model. After that, the optimized parameters are verified to evaluate the reliability of the model on heat generation. The results of response surface optimization show that the optimized model error is less than 0.76% and the final temperature drops is 0.55 K. This novel model is reliable and accurate, which is helpful to improving the electrochemical and thermal performance of the battery. Also, it can provide optimized and feasible solutions for other similar kind of batteries, which offer the reference for design and optimization of the battery management system.