batterydata/paper-abstracts huggingface dataset:
In this paper, perovskite type La0.6Ca0.4CoO3 as a catalyst of oxygen reduction was prepared, and the structure and performance of the catalysts was examined by means of IR, X-ray diffraction (XRD), and thermogravimetric (TG). Mixed catalysts doped, some metal oxides were put also used. The cathodic polarization curves for oxygen reduction on various catalytic electrodes were measured by linear sweep voltammetry (LSV). A Zn–air battery was made with various catalysts for oxygen reduction, and the performance of the battery was measured with a BS-9300SM rechargeable battery charge/discharge device. The results showed that the perovskite type catalyst (La0.6Ca0.4CoO3) doped with metal oxide is an excellent catalyst for the zinc–air battery, and can effectively stimulate the reduction of oxygen and improve the properties of zinc–air batteries, such as discharge capacity, etc.
The core objective of any point-of-care (POC) testing program is to ensure that testing will result in an actionable management decision (e.g. referral, confirmatory test, treatment), within the same clinical encounter (e.g. POC continuum). This can but does not have to involve rapid tests. Most studies on POC testing focus on one specific test and disease in a particular healthcare setting. This paper describes the actors, technologies and practices involved in diagnosing major diseases in five Indian settings – the home, community, clinics, peripheral laboratories and hospitals. The aim was to understand how tests are used and fit into the health system and with what implications for the POC continuum.
A conducting α-LiFeO2-polypyrrole (α-LiFeO2-PPy) nanocomposite material was prepared by the chemical polymerization method as a cathode material for lithium-ion batteries. The porous α-LiFeO2 was prepared via the microwave hydrothermal method and a post-annealing. The X-ray diffraction, Fourier transform infrared spectroscopy, and field emission scanning electron microscopy measurements showed that the α-LiFeO2 nanoparticles were coated with PPy. The polypyrrole coating improves the reversible capacity and cycling stability (104mAhg−1 at 0.1C after 100 cycles) for lithium-ion batteries. Even at the high rate of 10C, the electrode showed more than 40% of the capacity at low rate (0.1C).
Publisher Summary This chapter outlines the system requirements, enabling technologies, and system evaluation methodologies covering the various aspects of the current status of optical transceivers in the context of passive optical network (PON) applications. PON transceivers are unique bidirectional devices that use different wavelengths to transmit and receive signals between the optical line terminal (OLT) and the optical network units (ONUs) over a single fiber. Optical transceivers rely on the use of semiconductor lasers and detectors, in conjunction with integrated circuits (ICs), and novel packaging technologies to provide cost-effective means for transmitting and receiving analog and digital signals over fiber-optic cables. The different types of PONs, i.e., BPON, EPON, and G-PON, differ in the up- and downstream transmission bit-rates, reaches, split ratios, and burst-mode dynamics, which impacts the specifications of the respective transceivers. One of the critical issues for PON transceivers is the performance/cost ratio measured by the technical specifications and the unit cost of the optical transceivers. These new technologies are used to help in reducing the number of discrete components, improving the manufacturing yield, increasing the production throughput, and reducing overall cost. However there are technological challenges in PON transceivers which include upstream burst-mode optical transmission technologies; optical transmitter output power as well as optical receiver sensitivity to satisfy the increasing system link budget requirements; and higher date rates. Another challenge is the increase in electrical and optical cross talk between the transmitting and receiving channels.
Concerns over escalating health-care costs have brought about significant changes in the way health-care organizations and professionals are compensated for their services. Capitation, the payment of a fixed fee to health-care providers in exchange for providing medical care when it is needed, has been a significant element of change in the health-care industry. The purpose of this paper is to propose a framework for the evolution of management accounting systems in a changing health-care environment. This framework suggests that the role of activity-based costing, life cycle costing, and value chain analysis becomes increasingly important as the payment for health-care services moves from fee for service reimbursement to capitation arrangements between insurance companies and health-care providers. Health-care organizations that design and implement accurate costing and evaluation systems will enhance their ability to compete successfully in this rapidly changing environment.
A nano-structured CoAl double hydroxide with an average particle size of 60–70nm was prepared by a chemical co-precipitation. It was used as a positive electrode for the asymmetric hybrid supercapacitor in combination with an active carbon negative electrode in KOH electrolyte solution. The electrochemical capacitance performance of this kind of hybrid supercapacitor was investigated by means of cyclic voltammetry, electrochemical impedance spectroscopy and galvanostatic charge–discharge tests. A specific capacitance of 77Fg−1 with a specific energy density of 15.5whkg−1 was obtained for the hybrid supercapacitor within the voltage range of 0.9–1.5V. The supercapacitor also exhibits a good cycling performance and keep 90% of initial capacity over 1000 cycles.
Crossover of vanadium ions through the membranes of all-vanadium redox flow batteries (VRFB) is an issue that limits the performance of this type of flow battery. This paper reports on the preparation of a sol–gel derived silica nanocomposite anion exchange membrane (AEM) for VRFBs. The EDS and FT-IR characterizations confirm the presence and the uniformity of the silica nanoparticles formed in the membrane via an in situ sol–gel process. The properties of the obtained membrane, including the ion-exchange capacity, the area resistance, and the water uptake, are evaluated and compared to the pristine AEM and the Nafion cation exchange membrane (CEM). The experimental results show that the permeability of the vanadium ions through the silica nanocomposite AEM is about 20% lower than that of the pristine AEM, and one order of magnitude lower than that of the Nafion CEM. As a result, the rates of self-discharge and the capacity fading of the VRFB are substantially reduced. The Coulombic and energy efficiencies at a current density of 40mAcm−2 are, respectively, as high as 92% and 73%.
Battery temperature is a primary factor affecting the battery performance, and suitable battery temperature control in particular internal temperature control can not only guarantee battery safety but also improve its efficiency. This is however challenging as current controller designs for battery charging have no mechanisms to incorporate such information. This paper proposes a novel battery charging control strategy which applies the constrained generalized predictive control (GPC) to charge a LiFePO4 battery based on a newly developed coupled thermoelectric model. The control target primarily aims to maintain the battery cell internal temperature within a desirable range while delivering fast charging. To achieve this, the coupled thermoelectric model is firstly introduced to capture the battery behaviours in particular SOC and internal temperature which are not directly measurable in practice. Then a controlled auto-regressive integrated moving average (CARIMA) model whose parameters are identified by the recursive least squares (RLS) algorithm is developed as an online self-tuning predictive model for a GPC controller. Then the constrained generalized predictive controller is developed to control the charging current. Experiment results confirm the effectiveness of the proposed control strategy. Further, the best region of heat dissipation rate and proper internal temperature set-points are also investigated and analysed.
We present an investigation of the phase stability, electrochemical stability and Li+ conductivity of the Li10±1MP2X12 (M = Ge, Si, Sn, Al or P, and X = O, S or Se) family of superionic conductors using first principles calculations. The Li10GeP2S12 (LGPS) superionic conductor has the highest Li+ conductivity reported to date, with excellent electrochemical performance demonstrated in a Li-ion rechargeable battery. Our results show that isovalent cation substitutions of Ge4+ have a small effect on the relevant intrinsic properties, with Li10SiP2S12 and Li10SnP2S12 having similar phase stability, electrochemical stability and Li+ conductivity as LGPS. Aliovalent cation substitutions (M = Al or P) with compensating changes in the Li+ concentration also have a small effect on the Li+ conductivity in this structure. Anion substitutions, however, have a much larger effect on these properties. The oxygen-substituted Li10MP2O12 compounds are predicted not to be stable (with equilibrium decomposition energies >90 meV per atom) and have much lower Li+ conductivities than their sulfide counterparts. The selenium-substituted Li10MP2Se12 compounds, on the other hand, show a marginal improvement in conductivity, but at the expense of reduced electrochemical stability. We also studied the effect of lattice parameter changes on the Li+ conductivity and found the same asymmetry in behavior between increases and decreases in the lattice parameters, i.e., decreases in the lattice parameters lower the Li+ conductivity significantly, while increases in the lattice parameters increase the Li+ conductivity only marginally. Based on these results, we conclude that the size of the S2− is near optimal for Li+ conduction in this structural framework.
In using a LiPF6/ethylene carbonate–dimethyl carbonate electrolyte for lithium ion batteries (LIBs), a certain reductive reaction is known to occur at a relatively high potential (ca. 2.6 V vs. Li+/Li) on Sn electrode, but its details are still unknown. By means of in-situ X-ray reflectometry, X-ray photoelectron spectroscopy, scanning electron microscopy observations and electrochemical measurements (by using mainly Sn electrode, and additionally Pt, graphite electrodes), we have found out that this reduction eventually forms an inactive passivation-layer consisting mainly of insulative LiF ascribed to the reductive decomposition of LiPF6, which significantly affects the battery cyclability. In contrast, a solid-electrolyte interphase (SEI) is formed by the reductive reaction of the solvent at ca. 1.5 V vs. Li+/Li, which is lower than the reduction potential of LiPF6. However, we have found that the formation of SEI preempts that of the passivation layer when holding the electrode at a potential lower than 1.5 V vs. Li+/Li. Consequently, the cyclability is improved by suppressing the formation of the inactive passivation layer. Such a pretreatment would be quite effective on improvement of the battery cyclability, especially for a relatively noble electrode whose oxidation potential is between 1.5 V and 2.6 V vs. Li+/Li.
As the adoption of combined photovoltaic (PV) systems and battery storage systems (BSSs) for residential buildings increases, challenges for distribution network operators (DNOs) arise. Part of the attractiveness of investing in such systems stems from avoiding paying grid charges (GCs). Yet, the systems rely on the grid for PV feed-in and possibly contribute to PV grid integration challenges. Here, a bilevel optimization approach is developed to evaluate interdependencies between the DNO’s decision of raising GCs and the reaction of PV BSS investors. The model allows DNOs to trade-off the effectiveness of different measures to foster PV grid integration and the danger of starting a self-reinforcing process, potentially leading to grid defection. Included are two case studies that show that the new equilibrium between DNO and PV BSSs comes at a price of raised GCs and larger PV system sizes. Yet, in either case study, grid defection is not a realistic scenario as the marginal value of additional self-supply decreases with higher GCs. Compared to PV curtailment by the DNO, or grid reinforcements, fixed feed-in limits and power-based GCs reduce oversizing of PV BSSs and provide an operational incentive for peak-oriented BSS operation.
The effective scheduling of electric buses (EBs) for multiple vehicle types is essential for the sustainable practice of public transport. This paper proposes a new methodology for the electric vehicle scheduling problem with multiple vehicle types (MVT-E-VSP) in public transport based on a given multi-vehicle-type timetable. First, with explicit consideration of differences in driving range, recharging duration and energy consumption of EBs for multiple vehicle types, an optimization model is established to minimize annual total scheduling costs, including the purchase costs of EBs and chargers, the operating costs of deadheading and timetabled trips, etc. Then, a heuristic procedure is developed to find the optimal solution considering recharging trips and the substitution between electric vehicle (EV) types. Finally, the proposed methodology is validated using a real-world transit network in Daxing District, Beijing. The optimization result provides transit agencies with guidance on the purchase and schedule of EBs for multiple vehicle types, as well as the deployment of chargers. Comparative analysis indicates the proposed method considering the substitution between EV types reduces annual total scheduling costs by 15.93% compared with the conventional method. Sensitivity analysis reveals that the current recharging power (240 kW) and discharging depth (80%) are approximately economical.
Vitamin D deficiency during pregnancy may influence adverse outcomes in offspring. The aim of this systematic review and meta-analysis of observational studies was to assess the association between low prenatal concentrations of 25(OH)D (by using three different cut-off levels), preterm birth (PTB) and anthropometric and neurodevelopmental outcomes in offspring.
Elemental phosphorus (P) is extensively explored as promising anode candidates due to its abundance, low-cost and high theoretical specific capacity. However, it is of great challenge for P-based materials as practical high-energy-density and long-cycling anodes for its large volume expansion and low conductibility. Here, we significantly improve both cycling and rate performance of red P by cladding the nanoconfined P film on interconnected multi-walled carbon nanotube networks (P-MWCNTs composite) via facile wet ball-milling. The red P-MWCNTs anode presents a superior high reversible capacity of 1396.6 mAh g−1 on the basis of P-MWCNTs composite weight at 50 mA g−1 with capacity retention reaching at ∼90% over 50 cycles. Even at 1000 mA g−1, it still maintains remarkable specific reversible capacity of 934.0 mAh g−1. This markedly enhanced performance is ascribed to synergistic advantages of this unique structure: Intimate contacts between nanosized red P and entangled MWCNTs not only shorten the transmission routes of ions through MWCNTs toward red P, but also motivate the access with electrolyte to open structures of P film. Besides, the confined nanosized P film moderate volume expansions effectively and the entangled MWCNTs networks acted as conductive channels activate high ionic/electronic conductivity of the whole electrodes.
Partial lithiation strategies for silicon composite electrodes are experimentally investigated in this article. Two types of partial lithiation, i.e. voltage- and capacity-control strategies, are presented. Capacity loss and irreversibility of silicon electrodes are significantly suppressed by either partial lithiation strategy without any complicated modifications or treatments. The capacity of partially lithiated silicon electrodes is even higher than that of fully lithiated one after certain cycles. The images of scanning electron microscope suggest that the mechanical damage generated in partially lithiated electrodes is less than that in fully lithiated one. Furthermore, after dozens of cycles with partial lithiation, capacity decay also slows down in subsequent full charge-discharge cycles. The presented experimental results suggest that the partial lithiation strategy relieves the coupled mechanical-electrochemical degradation and is a promising approach for the long-term use of silicon composite electrodes.
Medication nonadherence should be suspected in elders who experience a decline in functional abilities. Predictors of medication nonadherence include specific disease states, such as cardiovascular diseases and depression. Technological aids to assessing medication adherence are available, but their utility is, thus far, primarily limited to a few research studies. These computerised devices, which assess adherence to oral and inhaled medications, may offer insight into difficult medication management problems. The most practical method of medication adherence assessment for most elderly patients may be through patient or caregiver interview using open-ended, nonthreatening and nonjudgmental questions.
A reference electrode based on a lithium–tin alloy was used to study electrode potential change during hybrid pulse power characterization (HPPC) and electrochemical impedance spectroscopy (EIS) measurements on lithium-ion cells. The cells contained a LiNi0.8Co0.15Al0.05O2-based positive electrode, a graphite-based negative electrode, and a LiPF6-bearing ethylene carbonate: ethyl methyl carbonate (EC:EMC) electrolyte. The cells were prepared and tested in an argon-atmosphere glove box to minimize the impact of moisture and oxygen. The reference electrode was prepared from a 25μm-diameter, tin-coated copper wire; in situ lithiation produced a Li x Sn (x ∼ 4.4) alloy that displayed a relatively stable voltage at room temperature. The impedance data obtained from these measurements were reproducible and self-consistent. Data from cells aged at 55°C showed that the positive electrode impedance increase was the main contributor to cell impedance rise, especially during the first month of aging.
Mobile offloading is a promising technique to aid the constrained resources of a mobile device. By offloading a computational task, a device can save energy and increase the performance of the mobile applications. Unfortunately, in existing offloading systems, the opportunistic moments to offload a task are often sporadic and short-lived. We overcome this problem by proposing a social-aware hybrid offloading system (HyMobi), which increases the spectrum of offloading opportunities. As a mobile device is always co-located to at least one source of network infrastructure throughout of the day, by merging cloudlet, device-to-device and remote cloud offloading, we increase the availability of offloading support. Integrating these systems is not trivial. In order to keep such coupling, a strong social catalyst is required to foster user’s participation and collaboration. Thus, we equip our system with an incentive mechanism based on credit and reputation, which exploits users’ social aspects to create offload communities. We evaluate our system under controlled and in-the-wild scenarios. With credit, it is possible for a device to create opportunistic moments based on user’s present need. As a result, we extended the widely used opportunistic model with a long-term perspective that significantly improves the offloading process and encourages unsupervised offloading adoption in the wild.
The current study evaluates existing and new validity evidence for the Academic Motivation Scale (AMS; Vallerand et al., 1992). We first provide a narrative review synthesizing past research, and then conduct a validity investigation of the scores from the measure. Data analysis using a sample of 1406 American college students provided construct validity evidence in the form of a well-fitting seven-factor model and adequate internal consistency of the item responses. Convergent and discriminant validity evidence provided insight into the distinctiveness of the seven subscales. However, support for the scale’s simplex structure, which would represent the self-determination theory continuum, was not fully substantiated. Implications for theory and the scale’s use in the current form are discussed.
Energy dispersive x-ray spectroscopy (EDS) is evaluated regarding its applicability for revealing the binder distribution in lithium-ion battery electrode films. Graphite anodes comprising carbon black and PVDF binder are subject to varying drying conditions during solvent removal in order to adjust different binder distributions; fluorine is used as a marker for the presence of PVDF. For electrodes of about 70 μm thickness the fluorine concentration is detected at the surface of the electrode film as well as at the interface between electrode film and current collector foil. It is clearly visible by EDS that increasing drying temperatures (and drying rates) result in an accumulation of binder at the surface and a corresponding depletion at the interface. It is demonstrated on the basis of ion-milled cross-sections of thick electrodes (ca. 400 μm) that a quantitative mapping of the binder distribution delivers additional information about concentration gradients in dependence of the drying parameters.
Here we report on low molecular weight organic acids in root exudates and soil solutions of Norway spruce and silver birch grown in rhizoboxes, sterile microcosms and the field. Monocarboxylic acids dominated in all three experimental systems. Formic, shikimic and oxalic acids were found in both spruce and birch microcosms. Fumaric acid was exclusive for spruce, while lactic, malonic, butyric and phthalic acids were only found in the birch microcosms. In spruce rhizoboxes oxalic, lactic, formic, butyric and pthalic acids were found. In addition, citric, adipic, propionic, succinic and acetic acids were observed in the rhizosphere of birch. Behind root windows in the field, only oxalic and lactic acids were found in the rhizosphere of spruce fine roots, whereas also formic and phthalic were observed close to birch fine roots, all at low concentrations. The rhizosphere of mycorrhizal short roots of birch contained butyric acid along with the acids observed for birch fine roots. Our results emphasise that characteristics of both the trees e.g. species, developmental stage, root density, mycorrhizal status, and the experimental system, i.e. growth conditions are important for the composition and the amount of organic acids. We conclude that the rhizosphere of birch contains more organic acids at higher concentrations than spruce.