batterydata/paper-abstracts huggingface dataset:
We investigated whether parenting and child behavior improve following psychosocial treatment for Attention-Deficit/Hyperactivity Disorder, Predominantly Inattentive Presentation (ADHD-I) and whether parenting improvements mediate child outcomes. We analyzed data from a randomized clinical trial investigating the efficacy of a multicomponent psychosocial intervention (Child Life and Attention Skills, CLAS, n = 74) in comparison to Parent-Focused Treatment (PFT, n = 74) and treatment as usual (TAU, n = 51) for youth with ADHD-I (average child age = 8.6 years, range 7–11 years, 58 % boys). Child and parent/family functioning were assessed prior to treatment, immediately following treatment, and at follow-up into the subsequent school year using parent and teacher reports of inattention, organization, social skills, academic competency (teachers only), parenting daily hassles, and positive and negative parenting behaviors (parents only). Both treatment groups improved on negative parenting and home impairment, but only CLAS families also improved on positive parenting as well as academic impairment. Improvements in positive and negative parenting mediated treatment effects on child impairment independent of improvements in child inattention, implicating parenting as an important mechanism of change in psychosocial treatment for ADHD-I. Further, whereas parent-focused training produces improvements in negative parenting and impairment at home for children with ADHD-I, a multicomponent approach (incorporating child skills training and teacher consultation) more consistently produces improvements at school and in positive parenting, which may contribute to improvements in social skills into the next school year.
1D nanostructured sodium vanadium oxide, i.e. Na2V6O16·nH2O, was introduced as a novel anode material for aqueous sodium ion batteries. A simple hydrothermal method is employed to prepare bundles of straight nanobelts whose crystals grow along the (010) direction. In each bundle, most nanobelts are aligned along the same direction. Sodium vanadium oxide hydrate has a layered structure, and that sodium ions are located at the interstices between layers. The solid-state diffusion coefficient of sodium ion in the bulk of Na2V6O16·nH2O is in the order of magnitude of 10–14 cmS−1. The discharge/charge capacity fades quickly in the initial few cycles upon galvanostatic cycling. It is revealed by ex-situ XRD analyses that this fast capacity fading can be attributed to the irreversible phase transition which mainly occurs in the first discharge. A full aqueous sodium ion battery was built using Na2V6O16·nH2O as anode and Na0.44MnO2 as cathode. Although its charge capacity fades quickly in the initial few cycles and stabilizes in the following cycles, its discharge capacity is comparatively stable upon cycling.
Germanium-based anode materials suffer from huge volume expansion during the lithium ion insertion/extraction process, along with particle agglomeration, resulting in electrodes destruction and batteries failure. Ge nanoparticles embedded in spherical ordered mesoporous carbon (S-OMC/Ge) composite could effectively alleviate the defects in the cycle, which provided a novel material with stable cycle performance, high capacity and good conductivity. The S-OMC/Ge composite maintained reversible capacities of 996 mAh·g−1 after 160 cycles at a current density of 100 mA g−1 and 530 mAh·g−1 at a high rate of 1 A g−1, attributed to the synergistic effect between the support of spherical OMC and the high capacity provided by dispersed Ge particles.
A lithium ion battery (LIB) subjected to external heat may fail irreversibly. Manifestations of this failure include venting of potentially combustible gases and aerosols followed by a rapid self-heating accompanied by ejection of the battery materials. It is important to be able to quantify the dynamics and energetics of this process to ensure safety of the energy storage systems utilizing LIBs. Here we report on development of a new experimental technique for the measurement of energetics of a thermally-induced battery failure. This technique, Copper Slug Battery Calorimetry (CSBC), was employed to investigate a widely utilized LIB of 2200 mAh capacity at various states of charge (SOC). It was shown that this techniques yields time and temperature resolved data on the rate of heat production inside the failing battery. The total energy generated inside the battery was found to increase with increasing SOC to the maximum value of 34.0 ± 1.8 kJ. To capture the energetics of flaming combustion of the materials ejected from the battery, CSBC was coupled with a cone calorimeter, which measures heat released in a non-premixed flame. The maximum amount of energy released by the battery through flaming combustion of ejected materials was found to be 97.5 ± 12.4 kJ.
Nickel metal hydride (MH-Ni) batteries are widely used in hybrid electric vehicles (HEVs). Estimating a battery's state of charge (SOC) remains challenging in practical applications, and it is also the core technology. Because MH-Ni batteries exhibit high rates of self-discharge and have flat and broad charge-discharge voltage plateaus, the estimation of their SOC through their voltage, current, internal resistance, and temperature is not accurate and has a large cumulative error. In this study, a new method for estimating SOC based on battery's stable internal pressure is proposed using the one-to-one correspondence between the hydrogen equilibrium pressure and the reversible hydrogen-storage capacity described by the pressure–concentration–isotherm (P-C-T) curves of hydrogen storage alloys. The actual SOC and the stable internal pressure of the battery have a one-to-one correspondence after the battery was stored at different temperatures and SOCs, and this relationship is maintained after different cycling number and after four years of storage.
A first review of urban Africa's dependence on larger landscapes for water is presented. Tables document: changing water sources between 1970s and 1990s; industrial and domestic wastewater treatment and disposal; electricity generation's dependence on water. Nearby groundwater and rivers were used in the 1970s; increasingly distant sources supplied the 1990s. Domestic and industrial wastes pollute groundwater and rivers. Africa's electricity depends upon large amounts of water, as dammed rivers or for power plant operation. Preserving urban Africa's scarce water supplies requires recognition of urban–rural water cycle linkages and holistic, coordinated, and equitable regional policies and practices that support ecosystem function.
The powertrain plays an essential role in improving the tractive performance and the fuel consumption of fuel cell hybrid vehicles. This paper presents a comparative study of two different powertrains for fuel cell hybrid buses. The significant difference between the two powertrains lies in the types and arrangements of the electrical motor. One powertrain employs an induction motor to drive the vehicle, while the other powertrain adopts two permanent magnetic synchronous motors for near-wheel propulsion. Besides, the tiny difference between the proposed powertrain is the supply path of the fuel cell accessories, which can have an effect on the powertrain efficiency. The component parameters and energy management strategies for the two powertrain are determined. The fuel cell hybrid buses equipped with the two powertrains are developed, and some road tests are achieved, according to the chosen procedures or driving cycles. The paper focuses on the tractive performance and energy analysis of the powertrains based on the testing results. Finally, the paper summarizes the relative merits of the proposed powertrains.
Cardiac pacemakers are a critical management option for patients with rhythm disorders. Current efforts to develop leadless pacemakers have two primary goals: to reduce lead-associated post-procedural morbidity and to avoid the surgical scar associated with placement. After extensive studies on animal models and technological advancements, these devices are currently under investigation for human use. Herein, we review the evidence from animal studies and the technological advancements that have ushered in the era of use in humans. We also discuss different leadless pacemakers currently under investigation, along with limitations and future developments of this innovative concept.
Ti-doped O3-type Na[Tix(Ni0.6Co0.2Mn0.2)1-x]O2 is studied as a high-performance cathode material for practical sodium-ion batteries. The effect of partial Ti doping on the structural and electrochemical properties of O3-type Na[Ni0.6Co0.2Mn0.2]O2 materials is investigated by varying the Ti content (x) in Na[Ni0.6Co0.2Mn0.2]O2 from 0 to 0.01 to 0.03. Scanning electron microscopy images show that upon doping, the primary particles aggregate and form densely packed secondary particles, yielding enhanced mechanical strength and high tap density of ∼2.3 g cm−3. The compact morphology of the particles effectively minimizes the void volume for possible electrolyte penetration that usually leads to unwanted side reactions. In addition, partial doping of Ti in the transition-metal layer greatly improve the structural stability. By taking both morphological and structural advantages, the O3-type Na[Ti0.03(Ni0.6Co0.2Mn0.2)0.97]O2 cathode demonstrate the great enhancements of battery performances in terms of capacity, cycle retention, rate capability, and thermal properties. Pouch-type full cells assembled by combining the present cathodes with hard carbon anodes show good practical applicability, with an outstanding cycle retention of 77% over 400 cycles. The results of this study may open up a new avenue for designing and developing suitable transition metal oxide cathodes for high-performance sodium-ion batteries.
Numerous of lithium ion battery fires and explosions enhance the need of precise risk assessments on batteries. In the current study, 18650 lithium ion batteries at different states of charge are tested using a cone calorimeter to study the burning behaviors under an incident heat flux of 50 kW m−2. Several parameters are measured, including mass loss rate, time to ignition, time to explosion, heat release rate (HRR), the surface temperature and concentration of toxic gases. Although small quantities of oxygen are released from the lithium ion battery during burning, it is estimated that the energy, consuming oxygen released from the lithium ion battery, accounts for less than 13% of total energy released by a fully charged lithium ion battery. The experimental results show that the peak HRR and concentration of toxic gases rise with the increasing the states of charge, whereas the time to ignition and time to explosion decrease. The test results of the fully charged lithium ion batteries at three different incident heat fluxes show that the peak HRR increases from 6.2 to 9.1 kW and the maximum surface temperature increases from 662 to 934 °C as the incident heat flux increases from 30 to 60 kW m−2.
In addition to the symptom triad of intrusions, avoidance behaviour and hyperarousal, typical and frequent characteristics of acute and chronic posttraumatic disorders are neuropsychological disturbances of working memory and executive functions. So far, however, only a very limited number of studies have dealt with their effects on the capability to assess time-related information. The purpose of this prospective study therefore was to compare persons after an acute traumatic experience with healthy controls in the course of 12 months, focusing on their ability to estimate time as a measure of their readiness of attention. 39 participants aged 17–59 years (mean age = 35.1 years, who had experienced a traumatic event and exhibited symptoms of acute stress disorder) were compared with 38 healthy controls (mean age = 36.1 years) at eight times of measurement within a period of 12 months. Performance was determined by means of a prospective time estimation task. The participants had to estimate a time interval of 5 s, once with and once without feedback about the quality of the estimates. The time estimates by the traumatised persons were significantly less precise than those by the control group. Progress analyses have shown that trauma patients exhibit larger deviations from the defined time interval, both under feedback conditions and without feedback. Psychological traumatisation leads to both an acute and long-term, demonstrable impairment of time estimation ability. The recognizable disturbance of information processing may both be a cause and a result of clinical trauma symptoms.
Excitatory synapses are located in confined chemical spaces called the dendritic spines. These are atypical femtoliter-order microdomains where the behavior of even single molecules may have important biological consequences. Powerful chemical biological techniques have now been developed to decipher the dynamic stability of the synapses and to further interrogate the complex properties of neuronal circuits.
Nanostructured intercalating electrodes offer immense potential for significantly enhancing the performance of rechargeable rocking chair (e.g. Li+ and Mg2+) and asymmetric hybrid batteries. The objective of this work has been to develop a variety of cathode (e.g. V2O5, LiMnO2 and LiFePO4) and anode (e.g. Li4Ti5O12) materials with unique particle characteristics and controlled composition to reap the maximum benefits of nanophase electrodes for rechargeable Li-based batteries. Different processing routes, which were chosen on the basis of the final composition and the desired particle characteristics of electrode materials, were developed to synthesize a variety of electrode materials. Vapor phase processes were used to synthesize nanopowders of V2O5 and TiO2. TiO2 was the precursor used for producing ultrafine particles of Li4Ti5O12. Liquid phase processes were used to synthesize nanostructured LiMn x M1−x O2 and LiFePO4 powders. It was found that (i) nanostructured V2O5 powders with a metastable structure have 30% higher retention capacity than their coarse-grained counterparts, for the same number of cycles; (ii) the specific capacity of nanostructured LiFePO4 cathodes can be significantly improved by intimately mixing nanoparticles with carbon particles and that cathodes made of LiFePO4/C composite powder exhibited a specific capacity of ∼145mAh/g (85% of the theoretical capacity); (iii) nanostructured, layered LiMn x M1−x O2 cathodes demonstrated a discharge capacity of ∼245mAh/g (86% of the theoretical capacity) at a slow discharge rate; however, the composition and structure of nanoparticles need to be optimized to improve their rate capabilities and (iv) unlike micron-sized (1–10μm) powders, ultrafine Li4Ti5O12 showed exceptional retention capacity at a discharge rate as high as 10C in Li-test cells.
The development of efficient electrocatalysts for the energy-related reactions, based on earth-abundant elements, is extremely important for a sustainable energetic future. Herein, we report the application of Cu nanoparticles supported on undoped and N-doped graphene—Cu/GOE and Cu/GOE-u composites, respectively—as electrocatalysts for the oxygen reduction reaction (ORR). All the materials showed ORR electrocatalytic activities in alkaline medium. The Cu/GOE-u composite exhibited the most promising performance, with an onset potential of 0.84 V and a current density of jL = − 4.4 mA cm−2 (vs. 0.84 V and − 2.8 mA cm−2 for Cu/GOE), which revealed the great influence of the created Cu–Nx/C active sites on the ORR electrocatalytic activity. The pure GOE-u support showed worse performance than the GOE, demonstrating that the N-doping advantage is not linear and also depends on the type and amount of accessible active sites created. The N-doping allowed an increase in the selectivity for the 4-electron process, resulting in a % of H2O2 produced < 25% for Cu/GOE-u (vs. almost 75% for Cu/GOE). Both nanocomposites revealed good tolerance to methanol crossover, and the Cu/GOE-u displayed a moderate long-term electrochemical stability, with current retention of 84% after 20,000 s.
Efficient catalysts for the oxygen-evolution reaction, especially in alkaline media, are highly desired because of their application in various energy technologies. Now, a gold-supported NiCeOx catalyst is shown to have excellent catalytic activity due to synergistic geometric and electronic effects.
Electrical double layer characteristics and specific adsorption of anions at Bi and Cd single crystal planes from aprotic and other non-aqueous electrolytes, as well as mixtures of surface-inactive and surface-active ionic liquids have been studied and analysed. Strong influence of sp-metal electronic characteristics (concentration of charge carriers, effective mass of electrons) on the potential of zero charge and differential capacitance values have been demonstrated. Influence of solvent chemical composition and dielectric characteristics on the surface activity and Gibbs adsorption energy values of anions at sp-metal single crystal planes has been demonstrated. Influence of ionic liquid anion composition on the specific adsorption characteristic time constant at Bi(hkl) and Cd(0001) single crystal electrodes in comparison with aprotic and non-aqueous solvent based electrolytes demonstrates the role of the solvent properties on the adsorption process characteristics. The non-aqueous solvent (acetonitrile, ethylene carbonate, propylene carbonate and gamma-butyrolactone) based electrolytes, ionic liquids and ionic liquid mixtures discussed are important electrolytes applicable in electrical double layer capacitors, secondary-ion batteries and other electrochemical devices. Appreciable increase of specific energy and power densities has been demonstrated for supercapacitors with ionic liquid electrolytes containing iodide and bromide anions, development of which was based on the adsorption data collected and discussed.
Transmission electron microscopy (TEM) studies were carried out to elucidate cyclic deterioration phenomena for Li-rich layered cathode material Li[Ni0.17Li0.2Co0.07Mn0.56]O2. The results obtained show that the deterioration starts during the initial charge/discharge to higher potential over 4.5V, and leads to the formation of micro-cracks at the crystal surface and the distortion of crystal periodicity. These two kinds of defects lead to further non-crystallization of the crystal surface and the emergence of a very small amount of another possible phase. Our stepwise pre-cycling treatment effectively depressed the formation of the former two kinds of defects, and could significantly improve cyclic durability. The observation of non-crystallization at the cathode crystal surface, which would diminish the battery performance, is consistent with our preliminary ac impedance results.
The understanding of germanium Li-ion insertion/extraction reaction mechanism is drawing more and more attention in the field of Li-ion batteries. When a germanium thin film electrode is inserted with Li ions, the material remains amorphous until it crystallizes into Li15Ge4 as evidenced by X-ray diffraction. The local coordination environment of the Ge atoms of the intermediate amorphous phases was investigated by in situ X-ray absorption spectroscopy. Li-ion insertion and extraction were electrochemically controlled by continuous and intermittent galvanostatic methods. The evolution of the coordination number and interatomic distance of Ge–Ge and Ge–Li shells was determined as a function of Li composition. From a short range ordering perspective, it was observed that the first Ge–Ge interatomic distance increases and the Ge–Ge coordination number decreases with increasing Li content. The opposite is observed for the first Li–Ge interaction. Moreover, it was found that electrochemical lithiation is reversible at the atomic scale.
Nanofiber-based piezoelectric energy generators could be scalable power sources applicable in various electrical devices and systems by scavenging mechanical energy from the environment. This review article highlights recent advances in nanofiber nanogenerators, discusses their operation principles and addresses performance issues including energy conversion efficiencies and possible false artifacts during experimental characterizations. Piezoelectric nanogenerators made of PVDF (polyvinylidene fluoride) or PZT (lead zirconate titanate) and fabricated by means of electrospinning processes such as conventional, modified or near-field electrospinning (NFES) are the key focuses of this paper. Material and structural analyses on fabricated nanofibers using tools such as XRD (X-ray diffraction), FTIR (Fourier transform infrared), SHG (second harmonic generation), PFM (piezoresponse force microscopy) and Raman spectroscopy toward the fundamental characterizations of piezoelectric nanofibers are also described. We summarize the report by highlighting recent nanogenerator developments and future prospects including high power nanogenerators, energy storage/regulation systems and fundamentals on piezoelectricity.
An electrochemical cell representing a battery-supercapacitor hybrid is demonstrated with a Si anode and a TiO2 cathode based on Lithium chemistry. Both materials are fabricated as coaxial shells with an oblique nanocolumnar structure anchored on vertical aligned carbon nanofiber arrays. The Li+ ion transport and electrical connection is greatly enhanced with such nanoporous core-shell architectures, leading to optimal Li storage properties. The full theoretical capacity of the shell materials has been obtained at normal C-rates (C/1 to C/2) for Si (∼3,000 to 3500mAhg−1) and TiO2 (∼170mAhg−1) half-cells, respectively, with excellent cycling stability. More importantly, much higher rates (up to 4.7CSi for Si and 76CTiO2 for TiO2) can be applied at relatively small capacity loss, approaching the properties of supercapacitors. The charge-discharge profiles show battery-supercapacitor hybrid features, which are attributed to the short Li+ diffusion path across the solid materials and the large pseudocapacitive contribution from fast surface reactions. A full cell containing similar volume of Si and TiO2 shows a high specific energy (103Whkg−1) at low current rates, comparable to a decent battery, and a remarkable specific power (56,000Wkg−1) at high current rates, matching the state-of-the-art supercapacitors.
Japanese-based Sumitomo Metal Industries, which owns the subsidiary Sumitomo Sitix of Phoenix has completed its merger with Mitsubishi Materials Corporation, and renamed the subsidiary Sumitomo Mitsubishi Silicon Corporation (Sumco).
A variety of lithium aluminates containing two oligoether groups and two electron-withdrawing groups, CF3CO2, CF3SO3, (CF3SO2)2N or C6F5O, on aluminum atom were prepared. Viscous liquid salts were obtained by incorporation of oligoether substituents containing an average of 7.2 and 11.8 ethylene oxide repeating units. Ionic conductivity of the liquid salt was enhanced by incorporation of electron withdrawing groups on the aluminate center and was dependent on the chain length of oligoether groups. Temperature dependence of ionic conductivity was well fitted to Vogel–Tammann–Fulcher equation, indicating that ion motion was coupled to segmental motion of oligoether chains. Polymer electrolytes were prepared by mixing of the salt and poly(ethylene oxide) and exhibited a high ionic conductivity, a high lithium transference number, a wide potential window, and a good thermal stability.