batterydata/paper-abstracts huggingface dataset:
In this study, a simple and controllable two-step electrochemical process is described for the synthesis of graphene sheets (GS) film on a cleaned indium tin oxide (ITO) sheet electrode. Namely, the main procedures involve the electrophoretic deposition (EPD) of graphene oxide (GO) film onto ITO electrode and the subsequent in situ electrochemical reduction (ECR) of GO to generate GS film. X-ray photoelectron spectroscopy (XPS) measurement demonstrates that most of the oxygen-containing functional groups in GO film have been removed after ECR. By electrochemical measurements, the maximum specific capacitance of the prepared GS film electrode was calculated to be 156 F g−1, besides, the capacitance retention of the material remained 78% after 400 times of cycling, showing a promising prospect as supercapacitor materials.
A facile and template-free one-pot strategy is applied to synthesize MoO2 nanostructured particles via a hydrothermal methodology. Characterizations include X-ray diffraction, scanning electron microscopy, transmission electron microscopy and Brunauer–Emmett–Teller surface area, X-ray photoelectron spectroscopy, Raman scattering spectroscopy, cyclic voltammetry and galvanostatic cycling. The as-annealed MoO2 nanostructured particles exhibit interconnecting and carbon-free features. Due to the unique nanostructure, the MoO2 electrode has a high specific capacity of 824mAhg−1 at C/10 and high reversible capacity of 760mAhg−1 after 30 cycles as anode for lithium storage performance. The interconnected MoO2 nanostructured particles also exhibit an excellent rate performance. Microstructure investigations of the MoO2-based electrode after full-lithiation are performed to elucidate the lithium ion uptake/removal mechanism, which can help us understand the unique cycling behavior of MoO2 material.
Drones are increasingly being used to perform risky and labor intensive aerial tasks cheaply and safely. To ensure operating costs are low and flights autonomous, their flight plans must be pre-built. In existing techniques drone flight paths are not automatically pre-calculated based on drone capabilities and terrain information. Instead, they focus on adaptive shortest paths, manually determined paths, navigation through camera, images and/or GPS for guidance and genetic or geometric algorithms to guide the drone during flight, all of which makes flight navigation complex and risky. In this paper we present details of an automated flight plan builder DIMPL that pre-builds flight plans for drones tasked with surveying a large area to take photographs of electric poles to identify ones with hazardous vegetation overgrowth. The flight plans are built for subregions allowing the drones to navigate autonomously. DIMPL employs a distributed in-memory paradigm to process subregions in parallel and build flight paths in a highly efficient manner. Experiments performed with network and elevation datasets validated the efficiency of DIMPL in building optimal flight plans for a fleet of different types of drones and demonstrated the tremendous performance improvements possible using the distributed in-memory paradigm.
To investigate the association between lead powder use, as folk skin care, and blood lead level (BLL) in children, we studied 222 children up to 14-years old living in a Chinese rural area and administered a face to face interview with their parents to collect information on lead powder use and other potential exposure. We measured children's BLL at baseline and 2 years later after an intervention. The children were divided into three categories according to their use of lead powder: regular use, irregular use and never use. We applied multivariate linear regression to determine the association between lead powder use and elevated BLL. The average BLL of all children was 18 μg/dl; 56% of them had BLL of 10 μg/dl or higher. Lead powder use was significantly associated with elevated BLL. After adjusting for potential confounders the BLL of regular and irregular users was higher than non-users by 3.11 μg/dl and 1.47 μg/dl, respectively. Duration of lead powder use was positively associated with BLL, but the time since last use was inversely associated. A significant BLL reduction was observed 2 years later, and the greatest reduction (21 μg/dl) was seen in the youngest group of regular users. This study showed that traditional use of lead powder for a skin care purpose was a major contributor to elevated BLL in these children.
This paper presents the modeling and control of a push–pull converter integrated into a two-stage photovoltaic microinverter operating in island mode without backup energy storage components (batteries). A push–pull small signal model is presented, from which they are derived all transfer functions needed to implement the controllers that regulate the output current, input voltage and output voltage interacting with the MPPT algorithm. A significant contribution of the paper is the proposal of an innovative control structure that simultaneously regulates in island mode both the ac voltage and the dc voltage of the panels, in order to place it in the best operation point. Such operation point is calculated by a specific control loop that interacts with the MPPT algorithm. To validate the proposed concept, simulations in PSIM™ were carried out.
Magnesium-air (Mg-air) batteries are an important energy source used to power electronic equipment and automobiles. Metal-air batteries give more energy density due to surplus air involved in reduction reaction at air cathode. In this study, the scope of improvements in the efficiency of Metal-air batteries is investigated through addition of water soluble graphene (WSG) as inhibitor in NaCl electrolyte. The discharge performance, corrosion behaviour and electrochemical impedance are studied for (i) the conventional Mg-air battery using 3.5% NaCl and (ii) Mg-air battery with WSG-based 3.5% NaCl electrolyte. X-ray diffraction analysis for WSG is carried out and it shows the crystalline nature of WSG by an intense sharp peak at 26.3°. Scanning electron microscope study is also performed and shows the flake-like structure of WSG denoted by thin layers of carbon. The immersion of WSG in 3.5% NaCl electrolyte increased the current density from 13.24 to 19.33 mA cm−2. Meanwhile, the WSG-based Mg-air battery was found to hold specific discharge capacity of 1030.71 mAh g−1, which was higher than that obtained in 3.5% NaCl electrolyte (i.e., 822.85 mAh g−1). The WSG-based Mg-air battery shows good self-discharge capacity and higher electrochemical activity during discharge.
Plug-in hybrid electric buses with large battery packs exhibit salient advantages in increasing fuel economy and reducing toxic emissions. However, they may be subject to expensive battery replacement caused by battery aging. This paper designs an online, coordinated optimization approach, based on Pontryagin’s minimum principle, for a single-shaft parallel plug-in hybrid electric bus, aiming at minimizing the total cost of energy consumption and battery degradation. Specifically, three key contributions are delivered to complement the relevant literature. First, a capacity loss model for lithium ion batteries emulating dynamics of both cycle life and calendar life is exploited in the optimization framework, in order to highlight the importance of considering calendar life and its implication to overall energy management performance in real bus operations. Second, the online adaptive mechanism of the optimization method with respect to varying driving conditions is achieved by tracking two reference trajectories to adjust the state of charge and effective ampere-hour throughput of the battery. Finally, to verify the effectiveness of the proposed scheme, various comparative studies are carried out, accounting for different driving scenarios. Simulation results show that the maximum control errors between the proposed strategy and Pontryagin’s minimum principle are only 0.4% in the battery capacity loss and 2.7% in fuel economy under four random driving cycles, which indicates the prominent adaptability and optimization performance of the designed strategy.
Nanocomposites of TiO2 (anatase) with polypyrrole (Ppy) or poly(3,4-ethylenedioxythiophene) (PEDOT) were prepared via electrochemical routes. The deposition process of the conducting polymer films was performed in the presence of perchlorate, p-toluenesulphonate (TOS) or bis(trifluoromethylsulphonyl)imide (TFSI) anions in propylene carbonate (PC). The obtained electrode materials were characterized using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM). An improvement of lithium ion intercalation/de-intercalation properties of titanium(IV) oxide as a result of its interfacing with the polymers is evidenced. This effect was strongly dependent on the thickness of the polymer layer and closely related to the polymer facility for transporting of lithium ion. Polypyrrole properties, in contrast to the PEDOT case, are very sensitive to selection of the substrate material (Pt or Pt/TiO2) during electropolymerization. Polypyrrole deposited on a rough surface exhibits an improvement in its ion exchange abilities. The impact of underlying TiO2 layers on Ppy properties has an indirect (synergic) influence on the effectiveness of lithium ion intercalation into the oxide too. The properties of the composites were discussed also in view of the comparative electrochemical quartz crystal microbalance (EQCM) study focussing on ion transport properties of Ppy and PEDOT.
A type of γ-Fe2O3 nanoparticle/Ketjen Black (KB) composite material is synthesized by a solvothermal method combined with precursor thermal transformation. The structure and morphology are characterized by XRD, raman spectra, TG, nitrogen sorption, SEM, TEM and EDS. The results show that the composite has a uniform nanoporous network and well-dispersed γ-Fe2O3 particles with a size of ca. 5nm are embedded in the mesopores of KB. The γ-Fe2O3/KB exhibits superior eletrochemical performances to the bare γ-Fe2O3, especially at high current rate. The discharge capacity of the composite is 1100 mAh·g−1 at the first cycle and remains 988.8 mAh·g−1 after 100 cycles at 0.2C. Moreover, it also maintains a high discharge capacity of 697.8 mAh·g−1 at 2C and 410.1 mAh·g−1 at 5C after 100 cycles, respectively. Such improved electrochemical performances could be attributed to the superior conductivity and favorable structure of KB, which contributes to the improvement in electronic conductivity and structure stability of γ-Fe2O3 during the lithium ion insertion/desertion process.
Little is known about which ADHD core symptom or subtype is most associated with visuospatial planning deficit. This issue was investigated in a sample of 408 youths with current DSM-IV diagnosis of ADHD, and 332 youths without lifetime ADHD, aged 8–17 years (mean age 12.02±2.24). All the participants and their mothers were interviewed using the Chinese Kiddie Epidemiologic version of the Schedule for Affective Disorders and Schizophrenia to obtain information about ADHD symptoms and diagnosis and other psychiatric disorders. In addition to clinical assessments, the participants were assessed with the WISC-III and the Stocking of Cambridge task of the Cambridge Neuropsychological Test Automated Battery. Multi-level regression models were used for data analysis. The results showed that univariate analyses revealed that inattention, hyperactivity, and impulsivity were significantly associated with visuospatial planning, and the magnitude of such association was amplified with increased task difficulties. Only inattention independently predicted visuospatial planning in a model that included all three ADHD symptoms. After further controlling for comorbidity, age of assessment, treatment with methylphenidate, and Full-scale IQ, inattention was still independently associated with visuospatial planning indexed by mean moves needed to solve problems. In subtype comparison, participants with combined subtype and those with prominently inattentive subtype, rather than prominently hyperactivity/impulsivity subtype, had poorer visuospatial planning performance. Our findings indicate that inattention is independently associated with impaired visuospatial planning, and dimensional approach retains the important distinction among ADHD symptoms than subtype approach in understanding the neuropsychological functioning of ADHD.
Transition metal nitrides (TMN)/N modified graphene (N-rG-O) composites are prepared by annealing of Metaln+-EN (EN: ethylene diamine) chelate and G-O composite. Li-storage and cycling behavior of TMN/N-rG-O composite have been evaluated by galvanostatic discharge-charge and cyclic voltammetry in coin cells with Li-metal as counter electrode. FeN/N-rG-O, CoN/N-rG-O, FeCoN/N-rG-O, NiN/N-rG-O are prepared using this method, and all have shown pronounced cyclability and considerable high capacity value. Even a low loading of TMN (12.5% ±2.0%) on graphene can significantly improve the Li-ion storage capacity of graphene. For example, FeN/N-rG-O with FeN weight ratio of only 12.5% has an initial reversible capacity of 665±10 mAhg−1 at a current density of 50mAg−1, and the capacity value further increase consistently to 698 ±10 mAhg−1 after 50 cycles. The excellent cyclability, low charge/discharge potentials (<1.5V), high reversible capacity values of TMN/N-RG-O indicate they are prospective anodes for Li-ion batteries.
Objective: To determine the relative contributions of traumatic brain injury (TBI) and APOE ε4 allele status to cognitive functioning over time in people 55 years and older. Design: Observational. Setting: Research center at an urban medical center. Participants: 54 subjects with TBI and 41 participants with no history of TBI. Interventions: Not applicable. Main Outcome Measures: Factor scores measuring memory, processing speed, verbal fluency, and executive functioning derived from standardized neuropsychologic tests. Results: The neuropsychologic battery was administered twice postinjury, with a mean interval of 31.9±12 months between assessments. An initial analysis of covariance (ANCOVA), controlling for age and education, comparing the positive and negative APOE ε4 status groups yielded no significant differences between groups at either time point for any of the factors. However, when the TBI and non-TBI groups were compared, a main effect for group was found on the processing speed factor, with the TBI group performing worse than the non-TBI group at both time points (P<.001). ANCOVAs comparing both the positive and negative APOE ε4 status among TBI and non-TBI groups showed no significant between-group differences in cognitive functioning over time. Conclusions: In this study, older adults with TBI did not exhibit different rates of cognitive change over time from non-TBI counterparts and APOE ε4 status did not contribute significantly to changes in cognitive function. However, older adults with TBI did have greater cognitive impairment than their non-TBI counterparts at both assessment points on a factor measuring processing speed.
A series of highly branched sulfonated poly (fluorenyl ether ketone sulfone)s (HSPAEK) are synthesized by direct polycondensation reactions. The HSPAEK with 8% degree of branching is further investigated as membrane for vanadium redox flow battery (VRFB). The HSPAEK membrane prepared by solution casting method exhibits smooth, dense and tough morphology. It possesses very low VO2+ permeability and high ion selectivity compared to those of Nafion 117 membrane. When applied to VRFB, this novel membrane shows higher coulombic efficiency (CE, 99%) and energy efficiency (EE, 84%) than Nafion 117 membrane (CE, 92% and EE, 78%) at current density of 80 mA cm−2. Besides, the HSPAEK membrane shows super stable CE and EE as well as excellent discharge capacity retention (83%) during 100 cycles life test. After being soaked in 1.5 mol L−1 VO2 + solution for 21 days, the weight loss of HSPAEK membrane and the amount of VO2+ reduced from VO2 + are only 0.26% and 0.7%, respectively, indicating the superior chemical stability of the membrane.
Feedback interventions have proved to be effective at promoting energy conservation behaviour, and digital technologies have the potential to make interventions more powerful and scalable. In particular, real-time feedback on a specific, energy-intensive activity may induce considerable behaviour change and savings. Yet the majority of feedback studies that report large effects are conducted with opt-in samples of individuals who volunteer to participate. Here we show that real-time feedback on resource consumption during showering induces substantial energy conservation in an uninformed sample of guests at 6 hotels (265 rooms, N = 19,596 observations). The treatment effects are large (11.4% reduction in energy use), indicating that the real-time feedback induced substantial energy conservation among participants who did not opt in, and in a context where participants were not financially responsible for energy costs. We thus provide empirical evidence for real-time feedback as a scalable and cost-efficient policy instrument for fostering resource conservation among the broader public.
There is no lack of studies on “net zero energy buildings” (“nZEB”). However, the vast majority of these studies focus on theories and simulation. The actual operational performance of “net zero energy building” during occupation has been largely overlooked by previous studies. This study aims to investigate the operational performance of net “zero energy buildings” via the case study of an office building in Tianjin, China. Using simulation, the energy consumption of the building at design phase was estimated and a solar photovoltaic (PV) system was selected. A whole year operation of the occupied building showed that energy consumption of the case building was much higher than the energy generated from the solar PV system. This was mainly due to three issues. Firstly, the equipment was different in terms of category, quantity and running time between operation and design stages, leading to considerable underestimate of energy consumption at the design stage. Secondly, the operational strategies need to be further improved in order to regulate users’ behaviors. Thirdly, the efficiency of solar PV system was substantially reduced due to poor atmospheric environment (i.e. haze weather). Therefore, during the design process of “net zero energy buildings”, it is imperative to ensure that the energy simulation accurately reflects how the building will actually operate once occupied. The research also revealed other barriers to the design and implementation of “nZEB” in China, such as extra efforts required for effective communicating the capacity of the HVAC design and systems to clients, and the increased cost of “nZEB” (e.g. solar PV system) particularly for public buildings. Finally, the solar radiation intensity of standard year adopted in the simulation needs to be replaced by the most recent meteorological data.
To enable fast charging of lithium ion batteries, extensive attention is needed to reduce the heat generation rate to avoid thermal runaway. This work studies the impact of the fast charging protocol on thermal behavior and energy efficiency of a lithium ion battery cell for 30-minute charging with 80% rated capacity. A two-stage constant current (2SCC) charging protocol with different current level combinations is adopted to mitigate the temperature rise leading to thermal runaway and improve the charging energy efficiency, because different charging current will generate different rates of heat. An electrochemical thermal coupled model is developed to predict the heat generation rate, charging energy rate, and temperature rise with experimental validation. The simulation results indicate that the “high-low” charging protocols of the 2SCC fast charge can achieve a lower overall temperature rise and higher charging energy efficiency than both the “low-high” charging protocols and the standard one-stage constant current (1SCC) charging. Compared to the 1SCC charge, the 2SCC charging protocol can improve the overall charging energy efficiency by 1%. Additionally, the impact of the 2SCC charging protocol on the thermal behavior under different initial cell temperatures and the heat transfer coefficients are discussed.
The Diels-Alder reaction is a well-known [4+2] cycloaddition in organic chemistry, which is employed in this article as an efficient approach towards high-performance organic electrode materials since it can achieve the incorporation of more redox groups and extension of π systems in one step. As a proof-of-concept example, we reported that a hexalithium benzo[ghi]perylene hexacarboxylate (Li6-BPHC) by the lateral extension of well-known organic anode material, tetralithium perylene tetracarboxylate (Li4-PTC), via a facile Diels-Alder reaction, which has been demonstrated to not only store nearly six electrons per molecule at a current density of 280mAg−1 but also possess a highly stable cycling performance over 100 cycles.
The plating and stripping performance of sodium metal in an ionic liquid electrolyte is improved when including water as an additive. Herein we report for the first time the trend of improved cycling behavior of Na0/+ in N-methyl-N-propylpyrrolidinium bis(fluorosulfonyl)imide with 500 ppm H2O. The addition of water to this ionic liquid electrolyte promotes the breakdown of the [FSI]- anion towards beneficial SEI formation. The benefits during plating and stripping of sodium is observed as lower total polarization during symmetrical cell cycling and decreased electrode/electrolyte interface impedance. Sodium metal surfaces after cycling with 500 ppm H2O are shown to be smooth in morphology in comparison to lower additive concentrations. The outcome of adventitious moisture benefiting Na0/+ cycling in an ionic liquid, contrary to conventional electrolytes, allows flexibility in ionic liquid electrolyte design to the benefit of battery manufacturers.
Background Several organizations have underscored the crucial need for patient-centered decision tools to enhance shared decision-making in advanced heart failure. The purpose of this study was to investigate the decision-making process and informational and decisional needs of patients and their caregivers regarding left ventricular assist device (LVAD) placement. Methods In-depth, structured interviews with LVAD patients, candidates and caregivers (spouse, family members) (n = 45) were conducted. We also administered a Decisional Regret Scale. Results Participants reported LVAD decision-making to be quick and reflexive (n = 30), and deferred heavily to clinicians (n = 22). They did not perceive themselves as having a real choice (n = 28). The 2 most prevalent informational domains that participants identified were lifestyle issues (23 items), followed by technical (drive-line, battery) issues (14 items). Participants easily and clearly identified their values: life extension; family; and mobility. Participants reported the need to meet other patients and caregivers before device placement (n = 31), and to have an involved caregiver (n = 28) to synthesize information. Some participants demonstrated a lack of clarity regarding transplant probability: 9 of 15 patients described themselves as on a transplant trajectory, yet 7 of these were destination therapy patients. Finally, we found that decisional regret scores were low (1.307). Conclusions Informed consent and shared-decision making should: (a) help patients offered highly invasive technologies for life-threatening disease get past the initial “anything to avoid thinking about death” reaction and make a more informed decision; (b) clarify transplant status; and (c) focus on lifestyle and technical issues, as patients have the most informational needs in these domains.